Taliban Gun Down Girl Who Spoke Up for Rights http://www.nytimes.com/2012/10/10/world/asia/teen-school-activist-malala-yousafzai-survives-hit-by-pakistani-taliban.html?_r=1 KARACHI, Pakistan — At the age of 11, Malala Yousafzai took on挑战 the Taliban by giving voice to her dreams. As turbaned戴头巾 fighters swept through her town in northwestern Pakistan in 2009, the tiny schoolgirl spoke out about her passion for education — she wanted to become a doctor, she said — and became a symbol of defiance against Taliban subjugation压迫. On Tuesday, masked Taliban gunmen answered Ms. Yousafzai’s courage with bullets, singling找出 out the 14-year-old on a bus filled with terrified schoolchildren, then shooting her in the head and neck. Two other girls were also wounded in the attack. All three survived, but late on Tuesday doctors said that Ms. Yousafzai was in critical condition at a hospital in Peshawar白沙瓦, with a bullet possibly lodged嵌入 close to her brain. A Taliban spokesman, Ehsanullah Ehsan, confirmed by phone that Ms. Yousafzai had been the target, calling her crusade正义行动 for education rights an “obscenity.” 亵渎 “She has become a symbol of Western culture in the area; she was openly propagating宣传 it,” Mr. Ehsan said, adding that if she survived, the militants would certainly try to kill her again. “Let this be a lesson.” As Pakistan has struggled to address the Taliban’s tenacity, the militants have intensified their campaign to silence critics and drive out signs of government influence. That Ms. Yousafzai’s voice could pose such a threat to the Taliban — that they could see a schoolgirl’s death as desirable and justifiable — was seen as evidence of both the militants’ brutality and her courage. “She symbolizes the brave girls of Swat,” said Samar Minallah, a documentary filmmaker who has worked among Pashtun women. “She knew her voice was important, so she spoke up for the rights of children. Even adults didn’t have a vision like hers.” Ms. Yousafzai came to public attention in 2009 as the Pakistani Taliban swept through Swat, a picturesque valley once famed for its music and tolerance and as a destination for honeymooning couples. Her father ran one of the last schools to defy Taliban orders to end female education. As an 11-year-old, Malala — named after a mythic female figure in Pashtun culture — wrote an anonymous匿名 blog documenting her experiences for the BBC. Later, she was the focus of documentaries by The New York Times and other media outlets. “I had a terrible dream yesterday with military helicopters and the Taliban,” she wrote in one post titled “I Am Afraid.” The school was eventually forced to close, and Ms. Yousafzai was forced to flee to Abbottabad, the town where Osama bin Laden was killed last year. Months later, in summer 2009, the Pakistani Army launched a sweeping operation against the Taliban that uprooted an estimated 1.2 million Swat residents. The Taliban were sent packing, or so it seemed, as fighters and their commanders fled into neighboring districts or across the border into Afghanistan. An uneasy peace, enforced by a large military presence, settled over the valley. Ms. Yousafzai grew in prominence, becoming a powerful voice for the rights of children. In 2011, she was nominated for the International Children’s Peace Prize. Later, Yousaf Raza Gilani, the prime minister at the time, awarded her Pakistan’s first National Youth Peace Prize. Mature beyond her years, she recently changed her career aspiration to politics, friends said. In recent months, she led a delegation of children’s rights activists, sponsored by Unicef, that made presentations to provincial politicians in Peshawar. “We found her to be very bold, and it inspired every one of us,” said another student in the group, Fatima Aziz, 15. Ms. Minallah, the documentary maker, said, “She had this vision, big dreams, that she was going to come into politics and bring about change.” That such a figure of wide-eyed optimism and courage could be silenced by Taliban violence was a fresh blow for Pakistan’s beleaguered progressives, who seethed with frustration and anger on Tuesday. “Come on, brothers, be REAL MEN. Kill a school girl,” one media commentator, Nadeem F. Paracha, said in an acerbic Twitter post. In Parliament, Prime Minister Raja Pervez Ashraf urged his countrymen to battle the mind-set behind such attacks. “She is our daughter,” he said. The attack was also a blow for the powerful military, which has long held out its Swat offensive as an example of its ability to conduct successful counterinsurgency operations. The shooting occurred in the center of Mingora, Swat’s largest town, offering further evidence that the Taliban remain a deadly force. “This is not a good sign,” Kamran Khan, the most senior government official in Swat, said by phone. “It’s very worrisome.” The Swat Taliban are a subgroup of the wider Pakistani Taliban movement based in South Waziristan. The leader of the Swat Taliban, Maulvi Fazlullah, rose to prominence in 2007 through an FM radio station that espoused Islamist ideology. After 2009, Maulvi Fazlullah and his senior commanders were pushed across the border into the Afghan provinces of Kunar and Nuristan, where Pakistani officials say they are still being sheltered — a source of growing tension between the Pakistani and Afghan governments. But over the last year or so, small groups of Taliban guerrillas have slowly filtered back into Swat, where they have mounted hit-and-run attacks on community leaders deemed to have collaborated with the government. On Aug. 3, a Taliban gunman shot and wounded Zahid Khan, the president of the local hoteliers association and a senior community leader, in Mingora. The army maintains a tight grip on Swat, either directly through a large military presence in the valleys, or indirectly through private tribal militias tasked with keeping the Taliban at bay. But the military has also been accused of human rights abuses, particularly after a leaked videotape in 2010 showed uniformed men apparently massacring Taliban prisoners. In response to criticism, the army chief, Gen. Ashfaq Parvez Kayani, announced an inquiry into the shootings. An army spokesman said it was not yet complete. Shah Rasool, the police chief in Swat, said that all roads leading out of Mingora had been barricaded and that more than 30 militant suspects had been taken into custody. Reporting was contributed by Sana ul Haq from Mingora, Pakistan; Ismail Khan from Peshawar, Pakistan; Ihsanullah Tipu Mehsud from Islamabad, Pakistan; and Zia ur-Rehman from Karachi.
E1 reaction-induced synthesis of hydrophilic oxide nanoparticles in non-hydrophilic solvent DOI: 10.1039/C2NR32255B Nanoscale , 2012, 4 , 6284-6288 DOI: 10.1039/C2NR32255B Received 12 Aug 2012, Accepted 03 Sep 2012 First published on the web 06 Sep 2012 Abstract In this paper, tert-amyl alcohol was employed to directly react with metal chlorides to prepare oxide nanoparticles. Some typical metal oxide or hydroxides with different morphologies, such as TiO2 nanoparticles, TiO2 nanorods, FeOOH nanowires, Fe2O3 nanoparticles, SnO2 nanoparticles, can be easily fabricated through such some simple chemical reactions. E1 reaction was found to play the leading role in the synthesis of metal oxides attributed to better stability of tertiary carbocations in tert-amyl alcohol and the strong interaction of metal chlorides with hydroxyl groups that result in the easy dissociation of carbon-oxygen bonds in tert-amyl alcohol. SN1 reaction can also happen in certain reactions due to nucleophilic substitution of chloride ions for hydroxyl groups. As-prepared metal oxides show good compatibility with aqueous system while they were synthesized in non-hydrophilic solvent probably attributed to specific E1 reaction mechanism involving the generation of water, and can be directly incorporated into aqueous soluble polymer, such as PVA, to exhibit many promising applications.
\title{\huge What is mass?\\~\\~\\ \large Chapter one: Mass in Newtonian Mechanics and Lagrangian mechanics} \author{Wang Xiong} \section{Introduction} \subsection{What is physics?} Physics is the study of matter and its motion through space and time. So the fundamental concepts of physics are matter, space-time, and motion. \subsection{What are the most important questions?} The fundamental questions of physics are: \begin{enumerate} \item What is the physical world made of? \item What is the structure of space-time? \item How do things change through space-time? \end{enumerate} The deeper understanding of these fundamental concepts and more profound answers to these fundamental questions, indicate the development of physical theory. \subsection{Matter and Mass} Of these fundamental concepts, mass is the modeling of matter. On the one hand, different properties of matter may lead to different concepts of mass. So we may discover many different physical attribute of matter, and use many different concepts of mass. On the other hand, some concepts may appear very different at first, but as we see deeper and deeper, we find a single and unified origin of these different concepts of mass. This kind of development of physic concept is very interesting and profound. So one may distinguish conceptually between many different attributes of mass or different physical phenomena that can be explained using the concept of mass There is no doubt that the problem of mass is one of the key problems of modern physics. \subsection{Overview of these series of talks} ``To see a World in a Grain of Sand, And a Heaven in a Wild'' We will try to see the development and the whole picture of theoretical physic through the evolution of the very fundamental concept of \emph{mass}. \begin{enumerate} \item The inertial mass in Newtonian mechanics \item The Newtonian gravitational mass \item Mass in Lagrangian formulism \item Mass in the special theory of relativity \item $E = MC^2$ \item Mass in quantum mechanics \item Principle of equivalence and general relativity \item The energy momentum tensor in general relativity \item Mass in the standard model of particle physics \item The higgs mechanism \end{enumerate} \section{Mass in Newtonian Mechanics} \subsection{Newton's three laws of motion} Newton's laws of motion are three physical laws that form the basis for classical mechanics. They describe the relationship between the forces acting on a body and its motion due to those forces. They have been expressed in several different ways over nearly three centuries, and can be summarized as follows: \begin{enumerate} \item First law: Every object continues in its state of rest, or of uniform motion in a straight line, unless compelled to change that state by external forces acted upon it. \item Second law: The acceleration a of a body is parallel and directly proportional to the net force F acting on the body, is in the direction of the net force, and is inversely proportional to the mass m of the body, i.e., F = ma. \item Third law: When two bodies interact by exerting force on each other, these forces (termed the action and the reaction) are equal in magnitude, but opposite in direction. \end{enumerate} \subsection{Newton's law of universal gravitation} Newton's law of universal gravitation states that the gravitational force between two bodies of mass $m$ and $M$ separated by a distance $r$ is $$F=-G\frac{mM}{r^2}$$. \subsection{The MASS} The term ``mass' was introduced into mechanics by Newton in 1687 in his ``Principia''. There are the following properties of mass in Newtonian mechanics: \begin{itemize} \item Mass is a measure of the amount of matter. \item Mass of a body is a measure of its inertia. \item Masses of bodies are sources of their gravitational attraction to each other. \item Mass of a composite body is equal to the sum of masses of the bodies that constitute it; mathematically that means that mass is additive. \item Mass of an isolated body or isolated system of bodies is conserved: it does not change with time. \item Mass of a body does not change in the transition from one reference frame to another. \end{itemize} \subsection{The amount of matter} \label{subsec:mylabel1} Newton defined mass as the amount of matter. Macroscopically, mass is associated with matter. the mass of an object is somehow relate with the number and type of atoms or molecules it contains, and with the energy involved in binding it together (which contributes a negative "missing mass," or mass deficit). But matter, unlike mass, is poorly defined in science. The generally accepted definition of matter does not exist even today. This is partially because there are so many different kinds of matters with quite different properties. \subsubsection{Can matter have zero mass?} Some may claim that matter is anything that occupies space and has rest mass. Under this definition one will not consider photons -- particles of light -- as particles of matter, because they are massless. For the same reason they do not consider as matter the electromagnetic field. It is not quite clear whether they consider as matter almost massless neutrinos, which usually move with velocity close to that of light. %Of course it is %impossible to collect a handful of neutrinos similarly to a handful of %coins. But in many other respects both photons and neutrinos behave like %classical particles, while the electromagnetic field is the basis of our %understanding of the structure of atoms. On the other hand, the so-called %weak bosons $W^+$, $W^-$, $Z^0$ are often not considered as particles of %matter because they are too heavy and too short-lived. % %Even more unusual are such particles as gluons and quarks. Unlike atoms, %nucleons, and leptons, they do not exist in a free state: they are %permanently confined inside nucleons and other hadrons. \subsubsection{We only known so little about matter} Even more strangely, the ordinary matter, in the quarks and leptons definition, constitutes about 4{\%} of the energy of the observable universe. The remaining energy is theorized to be due to exotic forms, of which 23{\%} is dark matter and 73{\%} is dark energy. We have very little knowledge about the majority matter of the universe. Anyway roughly speaking, the mass is somehow the measure of amount of matter. \subsection{The inertia mass} Inertial mass is a measure of an object's resistance to changing its state of motion when a force is applied, which arises naturally from Newton's second law of motion. It is determined by applying a force to an object and measuring the acceleration that results from that force. An object with small inertial mass will accelerate more than an object with large inertial mass when acted upon by the same force. One says the body of greater mass has greater inertia. \subsection{How to measure the inertia} We can measure its acceleration (assuming only that we can readily measure length and time) and hence the force acting on it in terms of its mass. The relation between mass and force is given by$\vec {F}=m_i \ddot {\vec {r}}$. %Although it is quite usual to refer to the scalar coefficient $m$ in this %relation as the mass, strictly speaking, what we detect when we apply a %force to a body is its inertia. For any arbitrary body, the inertial mass is defined as follows: we take the body and let it interact, somehow, with a standard inertial mass (one kilogram). Both the body and the standard will accelerate towards or away from one another. Designating the acceleration of the body and of the standard by $a_{ }$and $a_s $, respectively, we can define the inertial mass by \ \subsection{The gravitational mass} The gravitational mass can be described as a measure of magnitude of the gravitational force which is \begin{itemize} \item exerted by an object (active gravitational mass), and \item experienced by an object (passive gravitational force) \end{itemize} when interacting with a second object. Newton's law of universal gravitation states that the gravitational force between two bodies of mass $m_G$ and $M_G$ separated by a distance $r$ is $$F=-G\frac{m_G M_G}{r^2}.$$ \subsection{How to measure the gravitational mass} The gravitational mass can be defined in a similar manner. We take a standard object and define its gravitational mass to be one unit; for convenience we will use the standard kilogram as a standard for both inertial and gravitational mass. We now place the body at some distance $r$ and let it interact gravitationally with the standard. The body will accelerate towards the standard. We define the gravitational mass of the body in terms of this acceleration and the distance between the objects: \ Alternatively, using $m_i =\frac{a_s }{a}$ we can write this as \ This gives the gravitational mass in kilograms. The limiting procedure $r\to \infty $ is needed in order to eliminate the effects of multipole fields, which depend on the mass distribution of the two bodies. Also, proceeding to the limit $r\to \infty $ eliminates the effect of shorter range forces (nuclear force, Van der Waals force etc.). At large distances only the gravitational and electrostatic forces will remain, but the latter can be eliminated by taking the precaution of keeping the standard body neutral. If we take two identical copies of the standard mass and let them fall towards each other, the acceleration of each serves to define the constant $G$: \ \subsection{Put together} With these precise definitions of $m_i $ and $m_G $ it is clear that the gravitational force between two particles is \ and the equation of motion is \ \subsection{Two conceputure differnet mass} Whether all particles fall in the gravitational field of the particle of mass $M_G $ with the same acceleration depends on whether all particles have the same value of $$\frac{m_i }{m_G }$$ If this ratio is a universal constant, it must have the value one (the standard body has this value by definition). The question is then, is the equation \ satisfied for all bodies? This is a question which can be answered only by experimental means. \subsection{The additive of mass} In Newtonian Mechanics, mass of a composite body is equal to the sum of masses of the bodies that constitute it; mathematically that means that mass is additive. Together with the believe that matter cannot be destroyed or eliminated, the mass is believe to be always a positive real number. \subsection{Mass is conserved quantity} Mass of an isolated body or isolated system of bodies is conserved: it does not change with time. This is the reflection of the believe that matter cannot be destroyed or created. Things will not be so obviously in relativity. \subsection{Mass is invariant} Mass of a body does not change in the transition from one inertial reference frame to another in Newtonian Mechanics. Things will not be so obviously in relativity. \section{Mass in Lagrangian Mechanics} \subsection{Elementary Introduction of Lagrangian Dynamics} Let's consider the Newton equation \ in the one-dimensional case, in which all the physical parameters depend on the variable $x$only. Assume that the \emph{force is conservative}, which means that it is given as the spatial derivative of the \textbf{potential energy} $U(x)$: \ Thus for this case Newton's equation can be re-written as \begin{equation} \label{eq1} m\ddot {x}=-\frac{dU}{dx}, \end{equation} where $ \dot {x}=\frac{dx}{dt}=\mbox{v} $ and $ \ddot {x}=\frac{d^2x}{dt^2}=a. $ Define the \textbf{Lagrangian} $L\left( {x,\dot {x}} \right)$as a function of two variables, the position $x$ and the speed $\dot {x}$, \begin{equation} \label{eq2} L\left( {x,\dot {x}} \right)=T\left( {\dot {x}} \right)-U\left( x \right)=\frac{1}{2}m\dot {x}^2-U\left( x \right), \end{equation} \begin{itemize} \item the kinetic energy $T\left( {\dot {x}} \right)=\frac{1}{2}m\dot {x}^2$ is a function of the speed variable only, \item and the potential energy is a function of the position only. \end{itemize} \subsubsection{The Euler-Lagrange equation} From Eq. (\ref{eq2}) one can easily see that \begin{equation} \label{eq3} \frac{\partial L}{\partial x}=-\frac{dU}{dx}, \quad \frac{\partial L}{\partial \dot {x}}=m\dot {x}=p. \end{equation} Then obviously \begin{equation} \label{eq4} \frac{d}{dt}\left( {\frac{\partial L}{\partial \dot {x}}} \right)=m\ddot {x}. \end{equation} With the use of Eq. (\ref{eq3}) Newton's Eq. (\ref{eq1}) becomes \ which is called \textbf{the Euler-Lagrange equation} in one dimension. \subsubsection{The Hamiltonian formulation} To find the Hamiltonian formulation of dynamics, we define first the Hamiltonian $H\left( {x,p} \right)$ as a function of two new variables, the momentum $p$ and the position $x$: $ H\left( {x,p} \right)=p\dot {x}-L\left( {x,\dot {x}} \right), $ which is just the total energy $T+U$ as \begin{equation} \label{eq5} H\left( {x,p} \right)=p\dot {x}-L\left( {x,\dot {x}} \right)=m\dot {x}^2-\left( {\frac{1}{2}m\dot {x}^2-U(x)} \right)=T+U. \end{equation} The Hamilton equations, which replace Newton's equation of motion Eq. (\ref{eq1}) are given by \begin{equation} \label{eq6} \dot {x}=\frac{\partial H}{\partial p},\dot {p}=-\frac{\partial H}{\partial x}. \end{equation} %\subsection{The principle of least action} \subsubsection{Two ways to look at the physical motion} One way to understand physical motion is through differential equations, which describe how physical quantities change continuously with time. If we known the position and momentum for this moment, we can calculate from the equation how the object will move in the next moment. There is an alternative approach to look at this. Supposed that there are infinite mathematically possible paths for a system. The task for physic law is to find out which one is the real path nature takes. It's interesting that the real path actually followed by a physical system is always that for which make some quantity minimized, or, more strictly, is stationary. %That is to say, the action satisfies a variational principle: the principle %of stationary action. The action is defined by an integral, %and the classical equations of motion of a system can be derived from %minimizing the value of the action integral. \subsubsection{The principle of least action} The formal definition of the principle of least action is that it is "the principle stating that the actual motion of a conservative dynamical system between two points takes place in such a way that a function of the coordinates and velocities, called the action, has a minimum value with reference to all other paths between the points which correspond to the same energy." \subsubsection{The action} In physics, action is an attribute of the dynamics of a physical system. It is a mathematical functional which takes the trajectory, also called path or history, of the system as its argument and has a real number as its result. Generally, the action takes different values for different paths The action $S$ of a system, which is a scalar quantity, is defined as the time integral of the Lagrangian function, \ Therefore the problem of the motion of a mechanical system can be stated as that of finding the path $x(t),t_1 \le t\le t_2 ,$ such that the action $S$ is minimal. From a mathematical point of view this class of problems belongs to the field of mathematics called variational calculus and a quantity defined like the action is named functional.~A functional will have its extremal value when its "variation" is equal to zero.~ (This is like a function having an extremal value when its derivative is equal to zero). Consider two points $A$ and$B$. There are many trajectories joining the points, but a mechanical system which is evolving between them is choosing the trajectory that makes the action functional extremal. Let's assume that $x(t)$is the real trajectory of the body. Let's us also imagine a second trajectory, which is very near to the first, given by $x(t)+\varepsilon h(t)$, where $h(t)$ is an arbitrary time dependent function and $\varepsilon $ is a constant satisfying the condition $\varepsilon 1$. Obviously at the ends of all varied paths $h(t)$ satisfies the conditions \begin{equation} \label{eq7} h\left( {t_1 } \right)=h\left( {t_2 } \right)=0. \end{equation} The value of the action integral, which is a scalar, will be necessarily different according to the path taken by the particle to go from $A$ to$B$, \ \ne S\left . \] To find the curve or curves and the path or paths that make the action extremal, we shall use the variation of the trajectory and evaluate the action for the extremal and for the varied trajectory. For the Lagrangian along the varied path we obtain, by using a Taylor series expansion, \ Therefore the variation of the action along the two paths is given by \ -S\left =\varepsilon \int_{t_1 }^{t_2 } {\left( {\frac{\partial L}{\partial x}h+\frac{\partial L}{\partial \dot {x}}\dot {h}} \right)dt} . \] The second term in the integrand can be transformed by using partial integration, \ _{t_1 }^{t_2 } -\int_{t_1 }^{t_2 } {\left( {\frac{d}{dt}\frac{\partial L}{\partial \dot {x}}} \right)h(t)dt=-\int_{t_1 }^{t_2 } {\left( {\frac{d}{dt}\frac{\partial L}{\partial \dot {x}}} \right)h(t)dt} } , \] since $h\left( {t_1 } \right)=h\left( {t_2 } \right)=0.$ Then the variation of the action integral for a very small $\varepsilon $ is \ -S\left }{\varepsilon }=\int_{t_1 }^{t_2 } {\left( {\frac{\partial L}{\partial x}-\frac{d}{dt}\frac{\partial L}{\partial \dot {x}}} \right)h(t)dt} . \] Since $h(t)\ne 0$for $t_1 tt_2 $, for the path $x(t)$followed by the particle between the two fixed points $A$and $B$be an extremal of the action$S$, it is necessary and sufficient that the quantity between the brackets in the integral be zero. Then this condition gives the Euler-Lagrange Equations: \ \subsection{All are in Lagrangian} Therefore the equation of motion of a particle under the action of a conservative force can be derived from the Principle of the Least Action. So all information about the dynamics of the system is contained in the $$L\left( {x,\dot {x}} \right)=T\left( {\dot {x}} \right)-U\left( x \right)=\frac{1}{2}m\dot {x}^2-U\left( x \right)$$ \subsection{Why such Lagrangian?} Lagrangian of free particle can be determined by space-time symmetries. In the above, we find the Lagrangian from the newton's law of motion. Also in reverse, if we known the right Lagrangian, we could derive the equation of motion through the Euler-Lagrange Equations. If we want do it in reverse, how could we find the right Lagrangian? One might wonder whether one must simply guess at the form of the Lagrangian, such as the choice $\dot {x}^2$ , or if there is a more basic principle for finding the right Lagrangian. \subsection{Symmetry is fearful!} One way of doing so, is by thinking the symmetry of space-time. \\~\\ \textbf{The remarkable thing is that certain symmetries are so powerful and so restrictive that they entirely determine the functional form of the Lagrangian, and therefore the equations of motion.} \subsection{Newtonian picture of the world} The very least we can say about our world according to Newtonian mechanics is: the Universe is made of particles, space and time. The positions of particles change with time, according to Newton's law of motion. In other words, we try to describe the Lagrangian as a function of position x, time t and velocity $\dot {x}\mbox{=}\frac{dx}{dt}$ . \textbf{The basic assumption about the Lagrangian of Newtonian mechanics} is then it has the form$$L_{{\kern 1pt}0} \left( {{\rm {\bf x}},{\rm {\bf \dot {x}}},t} \right)$$. \subsection{Properties of Lagrangian} The choice of a least action principle as the basis of a theory of dynamics immediately implies that the Lagrangian has certain properties. First, we get the same equations of motion if we multiply that function with an arbitrary constant. Second, we get the same motion if we add to the integrand the total time derivative of an arbitrary function of space-time: $${L}'\mbox{=}L+\frac{df\mbox{(x,t)}}{dt}$$ then $${S}'=\int {{L}'dt} \mbox{=}\int {Ldt} +\int {\frac{df\mbox{(x,t)}}{dt}dt} \mbox{=}S+f_B \mbox{-}f_A $$ The additional terms are fixed, so that they have no influence on the equations of motion. The above two properties of $L$ are mathematical consequences of our decision to use a least action principle. \subsection{Create Lagrangian from Symmetry principle} But further restrictions on $L$ must be built in by using clues from Nature. These may be of any kind, but in practice the most powerful and general have proven to be symmetries of space-time. To begin with, consider the general form Lagrangian of a free particle$$L_{0} \left( {{\rm {\bf x}},{\rm {\bf \dot {x}}},t} \right)$$. \subsubsection{Invariance under Spatial and Time Translations:} The first symmetry is the \textbf{\textit{homogeneity of space and time}}. That is to say, the motion of a free particle does not depend on the place from which we measure its progress, nor does it depend on the time at which we start our measurement. Accordingly, $L_0$ cannot explicitly depend on $\bf x$ or $t$, so that $$L_{{\kern 1pt}0} \left( {{\rm {\bf x}},{\rm {\bf \dot {x}}},t} \right)\mbox{=}L_{{\kern 1pt}0} \left( {{\rm {\bf \dot {x}}}} \right)$$ \subsubsection{Invariance under Spatial Rotations:} The second symmetry is that of \textit{the isotropy of space}. That is to say, the motion of a free particle does not depend on the orientation of our coordinate system. We conclude immediately that this means that $L_{0}$ cannot depend on the direction of${\rm {\bf \dot {x}}}$, but only depend on the magnitude. It must be invariant under any rotations:$$L_{{\kern 1pt}0} \left( {{\rm {\bf R}}{\kern 1pt}{\rm {\bf \dot {x}}}} \right)=L_{{\kern 1pt}0} \left( {{\rm {\bf \dot {x}}}} \right)=L_{{\kern 1pt}0} \left( {\left| {{\rm {\bf \dot {x}}}} \right|} \right)$$ where \textbf{R} is a rotation operator and $\left| {{\rm {\bf \dot {x}}}} \right|=\sqrt {{\rm {\bf \dot {x}}}\cdot {\rm {\bf \dot {x}}}} $ \subsubsection{Invariance under Galilean Transformations:} There is yet another symmetry essential to the Newtonian mechanics: Galilean relativity. Coordinates of $S$ and $S'$, moving with relative velocity \textbf{v}, are related by $\mathbf{x}'=\mathbf{x}-\mathbf{v}t $ and $t'=t$ If $S$ is an inertial system in which Newton's 1$^{st}$ law holds, so is $S'$. \textbf{Physics law should be invariant under Galilean transformations, so does the Lagrangian.} How will this symmetry restrict the form of Lagrangian? We will see through the following trick. We denote $X=\frac{1}{2}\left| {{\rm {\bf \dot {x}}}} \right|^2$, using this new variable to express the free particle with Lagrangian $L_{{\kern 1pt}0} \left( {\left| {{\rm {\bf \dot {x}}}} \right|} \right)=L_{{\kern 1pt}0} \left( X \right)$. Thus the Euler-Lagrange equations are $$0=\frac{d}{d{\kern 1pt}t}\left( {\frac{\partial {\kern 1pt}L_{{\kern 1pt}0} }{\partial {\kern 1pt}{\rm {\bf \dot {x}}}}} \right) =\frac{d}{d{\kern 1pt}t}\left( {\frac{\partial {\kern 1pt}X}{\partial {\kern 1pt}{\rm {\bf \dot {x}}}}\frac{d{\kern 1pt}L_{{\kern 1pt}0} }{d{\kern 1pt}X}} \right) =\frac{d}{d{\kern 1pt}t}\left( {{\rm {\bf \dot {x}}}\frac{d{\kern 1pt}L_{{\kern 1pt}0} }{d{\kern 1pt}X}} \right)$$ where $\frac{\partial {\kern 1pt}X}{\partial {\kern 1pt}{\rm {\bf \dot {x}}}}=\frac{\partial }{\partial {\kern 1pt}{\rm {\bf \dot {x}}}}\left( {\frac{1}{2}{\rm {\bf \dot {x}}}\cdot {\rm {\bf \dot {x}}}} \right)={\rm {\bf \dot {x}}}$ \ \ \ Under the Galilean transformation \ \ The Euler-Lagrange equation can remain unchanged iff $$\frac{d^2L_{{\kern 1pt}0} }{d{\kern 1pt}X^2}=0$$ which imply that $$\frac{d{\kern 1pt}L_{{\kern 1pt}0} }{d{\kern 1pt}X}=const\equiv m$$ So $$L_{{\kern 1pt}0} =\frac{1}{2}m{\kern 1pt}\;{\rm {\bf \dot {x}}}^2+const$$ And the mass is nothing but just a integral constant in the Lagrangian. \subsection{Symmetry determine the dynamic} The conclusion is that Lagrangian of free particle is determined by spacetime symmetries. Note that the above mechanism of using symmetries to nail down the functional form of $L$ works wonderfully in other cases, too. In fact, all known forces of Nature can be derived from a symmetry principle which, remarkably enough, not only prescribes the Lagrangian of a free particle (like the way in which we obtained above), but the interactions as well. \section{Summary: what is mass then?} \begin{itemize} \item a quantitative measure of an object's resistance to acceleration \item or a measure of magnitude of the gravitational force \item or just a parameter in the Lagrangian? \item ...even stranger in the next lecture...coming soon... \end{itemize}
Reigning Olympic champion Zou Shiming of China set up a fight for gold again on Day 12, while there was a historic moment as the first women's Olympic Boxing medals were won - albeit they were bronze. Zou defeated Kazakhstan's Birzhan Zhakypov to contest another gold in the men's Light Fly Weight quarter-finals. The three-time world champion won the bout by 13 points to 10 as Zhakypov could not match him. Devendro Singh Laishram made an exit after losing to Irishman Paddy Barnes 23-18. Devendro was the last of the eight Indian boxers to bid farewell to the ring as the nation failed to claim a single medal in the men's Boxing. Thailand's Kaeo Pongprayoon won a well-fought bout against Aleksandar Aleksandrov from Bulgaria. Pongprayoon guaranteed at least a bronze as he booked his place in the semis, continuing his winning form on his Olympic Games debut. In the men's Light Welter Weight category, world bronze medallist and third seeded Vincenzo Mangiacapre defeated Kazakh Daniyar Yeleussinov 16-12 with a bout ending in a tense finish. British boxer Thomas Stalker missed out on a medal as he lost to Mongolia's Munkh-Erdene Uranchimeg 23-22. Uranchimeg said: 'My soul is full of emotion. I have been in the Olympics three times now - Athens, Beijing and now London. 'It has been my long-standing dream to get a medal, which I have now achieved.' Brazilian Yamaguchi Falcao Florentino caused another upset as he defeated top seed and reigning world champion Julio la Cruz Peraza from Cuba 18-15 in the men's Light Heavy Weight division. After a tied first round, Florentino overpowered the Cuban champion giving him little time to recover from his aggressive jabs and hooks. Despite the USA men going home without a medal for the first time in Olympic Games history, their women's team have a shot at gold after 17-year-old Claressa Shields overpowered Kazakhstans Marina Volnova 29-15. She was one of the big winners on a day when history was made, as the first women's Olympic Boxing medals were won. Shields will face powerful Russian Nadezda Torlopova in the final on Thursday after Torlopova, a former world champion at Super Heavy Weight, powered through 12-10 in a close fight with Li Jinzi of China. Katie Taylor moved into the Light Weight final with a 17-9 win over Tajikistan's Mavzuna Chorieva at the ExCeL. Her final will be against Russia's Sofya Ochigava, who advanced from her semi-final against Brazil's Adriana Araujo. Meanwhile, Great Britain's Nicola Adams will fight rival Ren Cancan of China for the women's Fly Weight gold after getting the better of five-time world champion Mary Kom in their semi-final. Ren made it through following her victory over Marlen Esparza of the USA, who was guaranteed a bronze medal - along with all the other semi-final losers. 原文见 http://www.london2012.com/news/articles/day-review-zou-through-women-reach-landmark.html
Olympic and world champion Lin Dan held off a remarkable fightback by Japan's Sho Sasaki to move into the semi-finals of the men's Singles competition on a day that saw China guarantee more medals. Lin faced the prospect of a shock exit as he was taken to three games and hauled back to 15-13 in the third after conceding five successive points, but he held on. The second seed's eventual 75-minute 21-12 16-21 21-16 win kept the man widely regarded as the best player of all time on course for a repeat of the Beijing 2008 final against Lee Chong Wei. Top-seeded Malaysian Lee, looking increasingly assured in his recovery from an ankle injury, was troubled only in the first game before seeing off India's Kashyap Parupalli 21-19 21-11. The semi-final line-up was completed by China's third seed Chen Long and seventh seed Lee Hyun-il, of Republic of Korea. Chen saw off Peter Gade, the Danish veteran playing his fourth and last Olympics, 21-16 21-13 while Lee stunned fourth seed Chen Jin of China 21-15 21-16. Three Chinese women will feature in the last four of the women's Singles along with Saina Nehwal of India. Nehwal, the fourth seed, came through against Europe's top player, Denmark's Tine Baun. Top seed Wang Yihan brushed off Cheng Shiao Chieh of Chinese Taipei 21-14 21-11, Wang Xin avoided an upset to beat Thailand's Intanon Ratchanok 17-21 21-18 21-14 and Li Xuerui overcame Hong Kong's Yip Pui Yin 21-12 22-20. China are guaranteed at least one gold as top seeds and world champions Zhang Nan and Zhao Yunlei set up a final with number two pair Xu Chen and Ma Jin in the Mixed Doubles. Both came through three-game battles against Denmark's Joachim Fischer and Christinna Pedersen and Indonesia's Tontowi Ahmad and Liliyana Natsir respectively. For the first time in Olympic history, Indonesia now cannot win a Badminton gold medal. In the women's Doubles, Tian Qing/Zhao Yunlei and Mizuki Fujii/Reika Kakiiwa will face each other after respective victories against Valeria Sorokina/Nina Vislova and Alex Bruce/Michele Li. Bruce and Li put up the strongest fight, going down 21-13 to the Japanese in the third game. The men's Doubles competition is heading for the semi-final stage. Top seeds Cai Yun and Fu Haifeng won their all-Chinese clash with Chai Biao and Guo Zhendong to set up a meeting with Malaysia's Koo Kien Keat and Tan Boon Heong. The other semi-final will be between second seeds Chung Jae-sung and Lee Yong-dae and Denmark's third seeds Mathias Boe and Carsten Mogensen. 原文见 http://www.london2012.com/news/articles/day-review-lin-through-china-guarantees-medals.html
Zhang Y L , Liu X H, Yin Y, Wang M Z, Qin B Q. Predicting the light attenuation coefficient through Secchi disk depth and beam attenuation coefficient in a large, shallow, freshwater lake. Hydrobiologia , 2012, 693: 29–37. Predicting the light attenuation coefficient through Secchi disk depth and beam .pdf
"The Hounds Of Winter" Mercury falling I rise from my bed, Collect my thoughts together I have to hold my head It seems that she's gone And somehow I am pinned by The Hounds of Winter Howling in the wind I walk through the day My coat around my ears I look for my companion I have to dry my tears It seems that she's gone Leaving me too soon I'm as dark as December I'm as cold as the Man in the Moon I still see her face As beautiful as day It's easy to remember Remember my love that way All I hear is that lonesome sound The Hounds of Winter They follow me down I can't make up the fire The way that she could I spend all my days In the search for dry wood Board all the windows and close the front door I can't believe she won't be here anymore I still see her face As beautiful as day It's easy to remember Remember my love that way All I hear is that lonesome sound The Hounds of Winter They follow me down A season for joy A season for sorrow Where she's gone I will surely, surely follow She brightened my day She warmed the coldest night The Hounds of Winter They got me in their sights I still see her face As beautiful as day It's easy to remember Remember my love that way All I hear is that lonesome sound The Hounds of Winter They harry me down %----------------------------------------------------------- %---------------------------------------------------------------- %------------------------------------------------（MATLAB） %-------------------------------------------------- %------------------------------------------------------- 穿越美女 请去LAOCAO处寻出处 %------------------------------------------------------------ 前身：POLICE POLICE every breath you take every move you make every bond you break every step you take i'll be watching you every single day every word you say every game you play every night you stay i'll be watching you o can't you see you belong to me how my poor heart aches with every step you take every move you make every vow you break every smile you fake every claim you take i'll be watching you since you've gone i been lost without a trace i dream at night i can only see your face i look around but it's you i can't replace i feel so cold and i long for your embrace i keep crying baby,baby,please o can't you see you belong to me how my poor heart aches every step you take every move you make every vow you break every smile you fake every claim you take i'll be watching you every move you make every step you take i'll be watching you %------------------------------------------------ %-------------------------------------------------- %------------------------------------------------------- The Shape of my HEART (《这个杀手不太冷》主题曲) He deals the cards as a meditation And those he plays never suspect He doesn't play for the money he wins He doesn't play for the respect He deals the cards to find the answer The sacred geometry of chance The hidden law of probable outcome The numbers lead a dance I know that the spades are the swords of a soldier I know that the clubs are weapons of war I know that diamonds mean money for this art But that's not the shape of my heart He may play the jack of diamonds He may lay the queen of spades He may conceal a king in his hand While the memory of it fades I know that the spades are the swords of a soldier I know that the clubs are weapons of war I know that diamonds mean money for this art But that's not the shape of my heart That's not the shape, the shape of my heart And if I told you that I loved you You'd maybe think there's something wrong I'm not a man of too many faces The mask I wear is one Those who speak know nothing And find out to their cost Like those who curse their luck in too many places And those who fear are lost I know that the spades are the swords of a soldier I know that the clubs are weapons of war I know that diamonds mean money for this art But that's not the shape of my heart That's not the shape of my heart
今年女王伊丽莎白二世在位已经整整六十年了。在庆祝女王在位六十周年之际，请看CBC录像《钻石女王》，透过威廉王子以及其他王室成员的视线，近距离地观看女王生活与君临天下的一幕幕。 http://www.cbc.ca/video/#/Shows/The_Passionate_Eye/1274903384/ID=2225820374 Diamond Queen, Part 1 April 21, 2012 Shows The Passionate Eye An intimate look at Queen Elizabeth II's life and reign through the eyes of Princes William and Harry, and other family members, as she celebrates her diamond jubilee
The world’s waterways were once the premier means of transporting goods, and as global economies look to reduce their carbon footprints, they could regain superhighway status. The US state of California, for example, is working to reduce emissions and road congestion by shifting freight transportation from trucks to barges. The California Green Trade Corridor is scheduled to open in 2012, and officials say upgrades to port facilities along the coast will create new opportunities to transport exports east to Asia, helping facilitate trade that is less energy intensive. Energy use among APEC member economies accounts for around 60% of world energy demand, and that figure is set to grow more than 30% by 2030 as those economies expand and their populations become more integrated. 1 With concerns over mobility and energy efficiency in mind, APEC is preparing its first Transportation and Energy Ministerial Conference in September, which will focus on how the APEC region can move toward a low-energy, low-carbon sustainable transport future. The meeting, the first joint initiative of APEC’s Energy and Transportation Working Groups, will build upon progress made separately by both bodies in May. At a gathering in Vancouver that month members from the Energy Working Group agreed to improve energy efficiency in transport, phase out inefficient fossil fuel subsidies and encourage low-carbon communities. In Montana in May, APEC’s trade ministers went to work on a plan aimed at furthering APEC’s green growth agenda. To promote better sharing of environmental technologies, they discussed ways to advance trade in green vehicles and technologies by encouraging technology transfer. Ministers also agreed to support the green agenda by promoting trade in remanufactured goods that reduce waste and save energy. Green growth is a key priority for APEC in 2011, as are ongoing efforts to strengthen integration, expand trade and promote regulatory cooperation between its 21 members. Not only does a greener economy create growth – largely through new jobs that, in turn, deepen prosperity – but it also helps grow trade and investment in the APEC region. “If everyone is addressing environmental concerns in the same way, if we have similar standards in place, similar testing procedures, it should increase trade among everybody, which again gets back to economic growth,” said Dr. Phyllis Genther Yoshida, the Lead Shepherd of APEC’s Energy Working Group and Deputy Assistant Secretary for the International Energy Cooperation. Greening the supply chain through energy-efficient freight transportation is one of four topics on September’s conference agenda and will enhance previous efforts APEC has put toward improving trade. Those include expanding the modes of transport so the flow of goods does not depend entirely on trucks or airplanes, and improving transport linkages to facilitate a more seamless movement of people, goods and services. APEC’s green agenda extends to its supply-chain connectivity action plan, a key initiative of APEC’s Committee on Trade and Investment (CTI). Through a supply chain framework laid out in 2009, APEC adopted a set of action plans that will optimize supply chain efficiency by addressing eight “chokepoints” that currently impede the flow of goods. Broadly, they relate to customs inefficiencies, inadequate infrastructure and the quality of logistical services and management. In addition to setting guidelines on regulations and tariffs and improving access to information through online references, such as the APEC logistics website, it is also conducting studies on environmental goods and services. For example, within the supply-chain connectivity action plan is a study and seminar that would assess the environmental benefits of transit-oriented development and compare case studies from developed and developing economies. To help improve the quality of APEC members’ logistics services and management, APEC economies are coordinating to share successful experiences of companies that have “greened” their supply chains to help enhance the competitiveness of regional logistics providers. 2 In 2007 APEC’s Leaders resolved to reduce the energy use needed for economic output to 25 percent of 2005 levels by 2030, and the APEC Leaders’ Growth Strategy adopted in Yokohama, Japan, in 2010 prioritizes a transition to a clean energy future. Based partly on pledges member economies made to support renewable energy and improved efficiency during the UN Climate Change Conference in Cancún last November, APEC is already set to surpass its 25 percent reduction goal. The Asia-Pacific Energy Research Center expects a 38 percent decline by 2030 under a business as usual scenario. 3 The move in the US for a higher fuel economy for cars and trucks, and industrial efficiency in China also count for a big chunk of the energy savings, said Dr. Yoshida, who predicts reductions will probably reach closer to 40 or 50 percent. That is APEC’s real mission; the pragmatic implementation of best practices, she says, and is the impetus behind September’s conference. In the run-up to that meeting, the Energy and Transportation Working Groups have been striving to intertwine and intensify their individual efforts. One of the four pillars of a new APEC-related Energy Smart Communities Initiative – announced last November by the US and Japan – is smart transportation. Already 16 projects are up and running, and the EWG will bring these examples to the APEC Economic Leaders’ Meeting in November. The four projects grouped under the smart transportation pillar will focus on reducing the costs, energy use and greenhouse gas emissions associated with transporting goods. The other pillars cover smart buildings, smart grids and smart jobs, which focuses on workforce training. “All of this is meant to take best practices, capacity building and research – like round robin testing for appliances, so we all are testing in the same way – and really provide that concrete piece that helps us get to a more secure APEC in terms of energy and obviously also helps with the environment and trade,” said Dr. Yoshida. September’s conference, a public-private forum that will bring leading CEOs and others from the private sector together with ministers from APEC member economies, is a way of sharing information about best practices and highlighting projects that can be replicated across the Asia-Pacific region. Private sector players worth highlighting could be FedEx, said Dr. Yoshida. In a recent news release the company said it plans to add more than 4,000 fuel-efficient vehicles, including hybrid-electrics, to its fleet around the US, dramatically reducing fuel use and carbon dioxide emissions in the delivery sector. Hybrid trucks improve fuel economy by 42 percent and cut greenhouse gas emissions by a quarter. FedEx’s current 330 hybrid-electrics have saved almost 300,000 gallons of fuel and reduced CO2 emissions by around 3,000 metric tons since 2005. 4 Many developing economies still struggle to bring fuel-efficient vehicles online as they work instead to improve inefficient logistics systems caused by poor infrastructure. But that challenge also offers an opportunity to “green” projects from their start, before too much investment is made in less green technologies, say officials at Indonesia’s Chamber of Commerce and Industry, or Kadin. Currently, businesses’ main concern is how to get products from point A to point B efficiently and without additional expenses. Kadin is working to help businesses see beyond the challenges posed by a lack of ports and railroads in an economy comprising 17,000 islands and spanning a distance as wide as the United States. “Kadin is developing green innovation awards and would love to see some innovative green projects that are suited to Indonesia’s complicated logistic requirements,” said Shinta Widjaya Kamdani, Vice Chairman for Environment and Climate Change at Kadin. Already Indonesia, one of the four economies participating in the smart transportation pillar, has begun testing green transport technologies. In 2009 it piloted a technology called Consload that allows shipping and logistics companies to work with SMEs to select goods for consolidation, decide how to pack them and determine the best routes for delivery. “We see our job as pragmatic implementers, so we can get to the point,” said Dr. Yoshida. “If we have a higher aspirational goal for energy intensity everybody feels like they can buy onto that because they see the tools coming into place to reach it.” According to the Intergovernmental Panel on Climate Change, transport, including freight, accounts for 13.1 percent of total global greenhouse gas emissions. It also accounts for 27 percent of total energy consumption in APEC economies. 5 Road and air transport release the most emissions, with rail and sea being cleaner alternatives. Since freight transport accounts for a substantial portion of energy use in the APEC region, one point of discussion at September’s conference will be how freight shippers can shift from energy-intensive transport modes, such as trucks, to rail and ship. “It’s not just about creating cleaner, lower-carbon trade, but also being more efficient and having more efficient products, which helps you produce more,” Dr. Yoshida said. For more information, contact: media@apec.org Energy security critical to prosperity, says APEC Secretariat Executive Director; APEC News Release, May 24, 2011. Committee on Trade and Investment, “2010 CTI Annual Report to Ministers: Appendix 5. Supply-Chain Connectivity (SC) Action Plan”; APEC#210-CT-01.6, November 2010. Energy Smart Communities Initiative (ESCI), power point presentation drafted by APEC’s Energy Working Group; July 2011. FedEx Alternative Energy website: http://about.van.fedex.com/corporate_responsibility/the_environment/alternative_energy/cleaner_vehicles Energy Smart Communities Initiative (ESCI), power point presentation drafted by APEC’s Energy Working Group; July 2011. 原文见 http://www.apec.org/Press/Features/2011/0905_greensupplychain.aspx
二甲双胍（ metformin ）最初提取自法国紫丁香，是应用最为广泛的治疗糖尿病药物。最近几年来，流行病学家开始注意到每天服用二甲双胍的糖尿病患者癌症发生率及与癌症相关的死亡率均降低。 在本周举行的2012年美国癌症研究协会（AACR）年会上，来自几个研究小组的资料表明， 二甲双胍对几种类型的均有抑制作用。 二甲双胍有望用于对其敏感的癌症预防与治疗。 A diabetes drug that treats cancer In the mid-2000s, epidemiologists began noticing that diabetics taking daily doses of metformin—the most widely prescribed medication for hyperglycemia and type 2 diabetes—showed decreased cancer incidence and cancer-related mortality. Originally isolated from the French lilac ( Galega officinalis ), metformin lowers circulating insulin through the indirect activation of AMP-activated protein kinase (AMPK)—a regulator of cellular metabolism. At the 2012 American Association for Cancer Research (AACR) annual meeting, held in Chicago this week, several research groups presented data supporting an inhibitory role for metformin in several types of cancers. The new studies suggest metformin could be adopted for both the prevention and treatment of metformin-sensitive cancers. In a phase II clinical trial involving 22 men with prostate cancer, for example, thrice-daily doses of 500 mg of metformin, given from the day of diagnosis until the routine prostatectomy nearly 6 weeks later, markedly reduced the size of the tumors in some of the men. “Although these are preliminary results, metformin appeared to reduce the growth rate of prostate cancer in a proportion of men,” Anthony Joshua, an oncologist at Princess Margaret Hospital in Toronto who presented the results at the meeting on Saturday, March 31, said in a press release. Similarly, treatment with metformin improved the survival rate of patients with both pancreatic cancer and diabetes by nearly two-fold, according to a retrospective study carried out by University of Texas researchers. Administration of metformin to mice with premalignant oral lesions also slowed the progression of the lesions into cancers by 70 to 90 percent, a team led by National Institutes of Health (NIH) researcher J. Silvio Gutkind reported. Specifically, the team found that metformin prevented the development of the lesions into head and neck cancers by inhibiting mTORC1—a protein complex known to respond a wide array of cellular signals including growth factors, nutrients, DNA damage, and energy levels. And in a study published yesterday (April 3) in Cancer Prevention Research , an AACR journal, researchers led by molecular biologist Geoffrey Girnun of the University of Maryland School of Medicine reported that metformin slowed tumor growth in mice with chemically induced liver cancer. They found that metformin decreased the expression of enzymes involved in lipid synthesis in the liver, an important process for tumor growth. http://the-scientist.com/2012/04/04/news-from-cancer-meeting/
摘自 《The War of Art-Break through the blocks and win your inner creative battle》 ， by Steven Pressfield. （P148-149,151） "Most of us define ourselves hierarchically and don’t even know it. It's hard not to. School, advertising, the entire materialist culture drills us from birth to define ourselves by others’ opinion. Drink this beer, get this job, look this way and everyone will love you. High school is the ultimate hierarchy. And it works; in a pond that small, the hierarchical orientation succeeds. There’s a problem with the hierarchical orientation, though. When the numbers get too big, the thing breaks down. In Massapequa High, you can find your place. Move to Manhattan and the trick no longer works. New York City is too big to function as a hierarchy. So is IBM. So is Michigan State. The individual in multitudes this vast feels overwhelmed, anonymous. He is submerged in the mass. He is lost. We have entered Mass Society. The hierarchy is too big. It doesn’t work any more. In the hierarchy, the artist looks up and looks down. The one place he can't look is that place he must: within. "
Message from the Under Secretary for Science, U.S. Department of Energy In November 2010, the President’s Council of Advisors on Science and Technology (PCAST) released the Report to the President on Accelerating the Pace of Change in Energy Technologies through an Integrated Federal Energy Policy. Among its recommendations to the Administration and to the Department of Energy (DOE) is a call to integrate the social sciences in energy. Specifically, the report calls for DOE to initiate with the National Science Foundation (NSF) “a multidisciplinary social science research program that will provide critical information and support for policy development that advances diffusion of innovative energy technologies.” In that same report, PCAST also recommended DOE undertake its first Quadrennial Technology Review (QTR) before the government embarks on a multiagency Quadrennial Energy Review (QER) for a national energy policy. Completed in September 2011, the QTR discusses the current energy landscape, the challenges we face, Six Strategies for accelerating energy technology innovation (three in the transport sector and three in the stationary sector), and DOE’s three modes of operation (harnessing capability, pushing technology, and serving as a source of information or a convener). Currently, DOE has inadequate information on how consumers interact with the energy system or how firms decide in which technologies to invest. The social sciences are the most important to the information role, and there is good reason to believe that insights from this area would improve the prospects for success in DOE’s efforts to move technologies toward commercialization. As a start on such studies, the Advanced Research Projects Agency-Energy is funding Stanford University’s H-STAR Institute and Precourt Energy Efficiency Center to develop an interactive software system to better understand energy efficiency and human behavior. The QTR asserts that the “aggregated actions of individuals and organizations determine many aspects of the energy system, with demands on the system and the balance of supply and demand affected as much by individual choice, preference, and behavior, as by technical performance.” Energy Secretary Steven Chu has affirmed the importance of integrating applied social science into DOE’s technology programs in order to better understand how technologies diffuse through a sector and are used in the real world. The five strategies and the specific actions recommended in this report from the American Academy of Arts and Sciences align with DOE’s capacity as a convener and highlight areas in which DOE can draw upon its role as a source of information. A strong partnership between DOE and NSF in creating and supporting an ongoing dialogue among technologists, policy communities, social scientists, federal agencies, local governments, and regulatory communities would be tremendously valuable in this endeavor. NSF’s recently released Sustainable Energy Pathways solicitations call for teams of researchers, including social scientists, to address sustainable energy. Mydiscussions with the NSF leadership show eagerness for DOE and NSF to move ahead together on developing interdisciplinary, systems approaches to energy. I would like to acknowledge Bob Fri, Leslie Berlowitz, and the American Academy of Arts and Sciences for taking the initiative to answer the PCAST call to action by organizing the Workshop on Social Science and the Alternative Energy Future held on May 19–20, 2011. This workshop is an exemplar of the Academy’s role in convening the different parts of the federal government and in stimulating interactions among a variety of actors. The workshop catalyzed discussion among thought leaders in the field who shared ideas on ways energy policy objectives and technology development objectives could benefit from insights produced through social science. In addition, it developed a research agenda intended to give us an improved understanding and to better inform us of energy technology applications through the social science lens. Lastly, I commend the participants for producing such a succinct summary of the many lessons from the workshop. This report not only makes insights from the workshop discussions available more broadly, but it poses social science questions relevant to the QTR’s Six Strategies and provides specific ideas about relevant lines of inquiry to which social scientists could provide direct value. Together with the QTR, this report takes us one step closer to implementing the PCAST recommendation to integrate social science in federal energy research and development. Steven E. Koonin Under Secretary for Science U.S. Department of Energy 原文见 http://www.amacad.org/pdfs/alternativeEnergy.pdf
2010年年初发表的文章，一直没有引用。到现在从Web of Knowledge里查还是没有引用，只是今天早上，看到一篇文章，是Alan L. Porter写的，9月份在线发表，还没有正式发表，引用了我们在JASIST发表的文章 Liu, Y. X., Rousseau, R. (2010). Knowledge diffusion through publications and citations: A case study using ESI-fields as unit of diffusion. Journal of the American Society for Information Science and Technology, 61(2), 340–351. 这篇文章的发表过程，我曾在 晒晒我在JASIST 上发文过程——兼叙西方期刊是否歧视中国作者 详细说过，先是鲁索说it looks very good,接着是匿名评审说very original and interesting, 但发表两年，一直没有引用，总让我觉得是老师抬爱自己的学生，而匿名评审也是看老师的面子才同意发表这篇文章。 后来，和Ismael Rafols合作写文章的时候，对一个问题有了争议，他说你们在JASIST中的文章是怎么怎么说的，才知道这篇文章发表出去，原来还是有人看的，科学网的博主瞿辉说他在看我的这篇文章，都是让我高兴的消息。 我知道Alan L. Porter在研究相关问题，是因为他和Ismael Rafols有个合作项目，所以，Rafols对他的研究动向很了解，他觉得我们的文章对Alan L. Porter有启发，就问鲁索是否可以把这篇文章推荐给Alan L. Porter，鲁索当然同意。 所以，我早知道Alan L. Porter读过我的这篇文章，也一直很希望他能喜欢这篇文章。Ismael Rafols说Alan L. Porter肯定会引用这篇文章的，我等了很久，他一直没有引用，这篇文章的引用一直是零，有些不甘心，于是自己引用了，可惜文章接受到现在一年了，还是没有发表，所以，引用还是零。 现在看到Alan L. Porter的这篇文章，到底还是引用了我的文章，感觉很兴奋。Alan L. Porter 是业内的一个大牌，而且和科技政策联系很紧密。这个引用开头不错，偷偷笑一下。 所以，形成一个学术圈，基于一个相同的问题，展开广泛的交流和争论，是科研开展的有效方式。昨天，安特大学有个研讨会，鲁索在会下和一个挪威人交流我最近投出去的两篇文章，那个人很感兴趣，要鲁索发送给他，鲁索给我要我最新版本的文章，文章还没有发表，就有人读，感觉有些exciting. 我注意到Alan L. Porter的文章也引用了于光于老师的文章，祝贺她。
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http://doc.sciencenet.cn/DocInfo.aspx?id=6176 Extraordinary light transmission through opaque thin metal film with subwavelength holes blocked by metal disks renchunxiao 添加于 2011-11-25 11:20:18 61次阅读 | 0次推荐 | 0个评论 We observed that when subwavelength-sized holes in an optically opaque metal film are completely covered by opaque metal disks larger than the holes, the light transmission through the holes is not reduced, but rather enhanced. Particularly we report (i) the observation of light transmission through the holes blocked by the metal disks up to 70% larger than the unblocked holes; (ii) the observation of tuning the light transmission by varying the coupling strength between the blocking disks and the hole array, or by changing the size of the disks and holes; (iii) the observation and simulation that the metal disk blocker can improve light coupling from free space to a subwavelength hole; and (iv) the simulation that shows the light transmission through subwavelength holes can be enhanced, even though the gap between the disk and the metal film is partially connected with a metal. We believe these finding should have broad and significant impacts and applications to optical systems in many fields. 作 者： Wen-Di Li, Jonathan Hu, and Stephen Y. Chou 期刊名称： 期卷页： 第卷 第期 页 学科领域： 信息科学 光学和光电子学 光学信息获取与处理 添加人是否为作者: 否 原文链接： http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-19-21-21098 遮挡纳米金属膜上小孔能增加光透性 堵住金属板上的小孔能阻挡光线从中通过，但到了纳米尺度，这一常识就不再管用。据美国物理学家组织网近日报道，美国普林斯顿大学工程师们实验发现，如果用盖子遮住纳米金属膜上的小孔，不仅挡不住光线，反而会增加透射光的数量，这一发现在光学仪器、超灵敏探测研究领域有着广阔的应用前景。相关论文发表在最近出版的《光学快讯》（ Optics Express ）杂志上。 该研究由普林斯顿大学机电工程教授斯蒂芬·周领导。在一项实验中，他和同事用了一种40纳米厚的金薄膜，上面布有直径60纳米、间距200纳米的微孔阵列。每个微孔都用小金盘盖住，小金盘比微孔要大40%，只在金属膜表面和盘之间有极微缝隙。他们先从薄膜下面照射激光，检查上面透过的光线，发现透过的光比没有盖子时要多70%。再从上面照射而在下面检测，结果同样。 “我们还以为小金盘能挡住所有的光，没想到会有更多光线通过。”周解释说，“小金盘好像变成了一种能捕获并辐射电磁波的‘天线’，它捕获了小孔一边的光，从另一边辐射出来。光波通过金属表面，经过盖子后大大增加。当激光遇到分子会产生微弱的信号，而用有微孔阵列的金属薄膜和金属盘，会使微弱的信号增强，在识别物质时更加敏感。” 周还指出，这一结果可能带来巨大的影响和应用价值。首先是遮光方面，在非常灵敏的光学仪器如显微镜、望远镜、分光仪及其他探测器中，如果想用在玻璃上涂金属膜的方法来遮光，结果可能适得其反。研究人员若想堵住所有的光线传播，需要重新思考他们所用的技术。比如在光刻印刷中，光会在玻璃板的金属膜上刻下细微花纹形成模板，引导光线通过某些位置而挡住其他地方，但由于这种封孔透光效应，工程师们要再检查一下模具是否达到预期的遮光效果。 其次，这种新技术能增加光透性。比如在近红外显微镜中，让光线通过直径仅有十亿分之几米的微孔，会增加透过光的数量，也就增加了观察目标的信息量，研究人员就能看到更多精微的细节。（来源：科技日报 常丽君） 《光学快讯》发表论文摘要（英文）
瑞典 作家、诗人和翻译家 现代主义、表现派和超现实主义作家、诗人和翻译家 文学家 Tomas Transtrmer 1931年4月15日出生于瑞典斯德哥尔摩 现年80岁 1956年毕业于斯德哥尔摩大学心理科学专业 此君13岁开始写作生涯，1954年(时年23岁）出版第一本诗歌集《十七首诗》 其后陆续出版有： 《路上的秘密》(1958)、《完成一半的天堂》(1962)、《钟声与辙迹》(1966)、《在黑暗中观看》(1970)、《路径》(1973)、《真理障碍物》(1978)及《狂野的市场》(1983)、《给生者与死者》(1989)、《悲哀的威尼斯平底船》(1996)等多卷 代表作： The Great Enigma New Collected Poems,等 特朗斯特罗默（TomasTranstromer)至今共发表163首诗。1990年患脑溢血导致右半身瘫痪后，仍坚持纯诗写作。他善于从日常生活入手，把有机物和科学结合到诗中，把激烈的情感寄于平静的文字里。他被誉为当代欧洲诗坛最杰出的象征主义和超现实主义大师。 The Nobel Prize in Literature 2011 was awarded to him (Tomas Transtrmer) "because, through his condensed, transluscent images, he gives us fresh access to reality" . 现实主义文学家
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