Opto propeller effect on Micro–Rotors with different handedness

Manipulating biomacromolecules and micro-devices with light is highly appealing.Opto driving torque can propel micro-rotors to translational motion in viscous liquid,and then separate microsystems according to their handedness.We study the torque of dielectric loss generated by circular polarized lasers.The unwanted axial force which causes the handedness independent translational motion is cancelled by the counter propagating reflection beams.The propelling efficiency and the friction torque of water are obtained by solving the Navier-Stokes equation.In the interesting range of parameters,the numerical friction torque is found to be linear to the angular velocity with a slope depending on the radius of rotor as r^3.The time-dependent distribution of angular velocity is obtained as a solution of the Fokker-Planck equation,with which the thermal fluctuation is accounted.The results shed light on the micro-torque measurement and suggest a controllable micro-carrier.

The Effect of Handedness on Supplementary Motor Area Activation during Complex Motor Tasks

Functional magnetic resonance imaging (fMRI) was used to assess the activity of supplementary motor area (SMA) in six right-handed and six left-handed healthy volunteers. Two manual tasks (self-initiated previously practiced and unpredictable visually guided) were used. Quantitative analysis of hemispheric and bilateral SMA activation was described as mean ± standard deviation of hot spots/total spots. The two tasks induced bilateral SMA activation. The laterality of SMA activation was affected by manual dominance. Left SMA was significantly more activated in right- and left-handers while performing the motor tasks with the right hand. Right SMA was more activated in the left-handers when the left hand was used. Task complexity was the most important factor influencing the degree of SMA activation.

Asymmetry in Resting Alpha Activity: Effects of Handedness

Study Aim: Frontal electroencephalographic (EEG) alpha band power during rest shows increased right, and/or de-creased left, hemisphere activity under conditions of state or trait withdrawal-associated affect. Non-right-handers (NRH) are more likely to have mental illnesses and dispositions that involve such withdrawal-related affect. The aim of the study was to examine whether NRH might be characterized by increased right, relative to left, hemisphere activity during rest. Methods: The present research investigated that hypothesis by examining resting EEG alpha power in consistently-right-handed (CRH) and NRH individuals. Results: In support of the hypothesis, NRH demonstrated de-creased right hemisphere alpha power, and therefore increased right hemisphere activity, during rest, compared to CRH. Conclusions: The study demonstrates further support for an association between increased right hemisphere activity and negative affect via an association between such EEG activity and NRH.

Strength, But Not Direction, of Handedness Is Related to Height

Left-handers are reputed to be shorter than right-handers. However, previous research has confounded handedness direction (left-versus right-handedness) with handedness strength (consistency with which one hand is chosen across a variety of tasks;consistent-versus inconsistent-handedness). Here, we support a relationship between handedness strength, but not direction, and stature, with increasing inconsistent-handedness associated with increasing self-reported height.

Handedness inversion of chiral mesoporous silica: A diffuse-reflectance circular dichroism study

Chiral mesoporous silica ribbons and rods with inversed handedness have been synthesized with the same enantio pure N-acylaminoacidat temperatures of 0℃and 20℃ respectively. With involving Cu^(2+)and meso-tetra(4-sulfonatophenyl)porphyrin(TPPS) as probes, ribbons and rods revealed opposite signals in diffuse-reflectance circular dichroism(DRCD) spectra, indicating the existence of inversed supramolecular chiral imprintings through helical stacking of amphiphiles. The structural evolution was systematically studied by the freeze-dried products sampled at different time after the addition of silica precursors. The H-bonding-depended molecular orientation probably controls the chiral sense upon forming chiral molecular stacking, which would be the origin of such handedness inversion

Effects of age, sex and manual task on hand preference in wild Rhinopithecus roxellana

Golden snub-nosed monkeys(Rhinopithecus roxellana),as typical arboreal group-living Old World monkeys,provide an appropriate animal model to research manual laterality and explore the factors affecting hand preference in non-human primates(NHP).This study investigated hand preference based on63 subjects and four spontaneous manual tasks(including unimanual and bimanual feeding and grooming), and assessed the effects of age, gender and type of task on handedness in R. roxellana.A population-level left-handedness was found not only in the bimanual coordinated tasks(bimanual feeding and grooming), but also in one unimanual reaching task(unimanual feeding). There were no significant differences between the sexes in either direction or strength of hand preference among any task. However, a significant difference between adults and juveniles was found in the unimanual feeding task. This is the first report on handedness in unimanual and bimanual feeding tasks that require bipedal posture in wild R. roxellana. Furthermore,this study demonstrated spontaneous feeding tasks reported previously only in the quadrupedal posture in this species, supporting the importance of factors such as posture and task complexity in the evolution of primate manual lateralization.

The Association between Surgery Laterality in Orthopedists and the Choices of Prostheses in Total Knee and Hip Replacement

Background: Most orthopedists are right-handed. However, osteoarthritis occurs with equal frequency over both sides. Does perfect and effective arthroplasty surgery require ambidextrous motor skills? Objectives: In this study, we aimed to investigate the clinical features of arthroplasty for hip and knee joints (THR and TKR) on different sides affected by orthopedist laterality. Patients and Methods: All right-handed orthopedists performed 64 right and 52 left primary THR among 100 patients, and 115 right and 118 left primary TKR among 192 patients. Clinical and surgical features were retrospectively reviewed and analyzed. The body mass index (BMI), inner diameter of acetabular cup liners (ACD), diameter of the femoral head (FHD), diameter of the femoral stem (FSD), and the femoral neck length (FNL) were included in THR-receiving patients. The BMI, femoral component (FC) size, tibial plate (TP) size, and thickness of articular surface inserts (ASI) were included in TKR-receiving patients. Results: No significant differences were observed in ACD, FHD and FSD between patients receiving right and left THR groups (p = 0.16, 0.11, and 0.05, respectively). Similarly, there were no significant differences in FC, TP, and ASI between patients receiving right and left TKR groups (p = 0.06, 0.80, and 0.46, respectively). However, FNL in left THR group was significantly longer than that in right THR group (p = 0.01). Conclusion: This study showed that dexterity or proprioception in handedness had no affect on bone resection and thicknesses of the polyethylene in TKR and acetabular reaming and femoral canal rasping in THR. However, it did lead to differences in femoral neck resection. Right-handed orthopedists significantly tend to perform excessive femoral neck cutting or prefer the larger size of FNL when performing left side THR, while no differences occur when performing TKR.

谈东西方语言中的尊右卑左

远在人类语言产生之前,方位的概念就已存在于人们的意识之中。古埃及人死后要头向东而葬,因为东方是太阳升起的地方,人们认为这样灵魂就能得到拯救。中国人更是注重方位。按照中国传统习俗,不管是造屋、

Charge disturbance/excitation in the Raman virtual state revealed by ROA signal: A case study of pinane

The Raman mode intensities are used to extract the bond polarizabilities which are the indication of the charge disturbance/excitation of the Raman virtual state. A classical formula based on the electric and magnetic dipolar coupling among the charges on the atoms is developed which relates the charges and vibrational amplitudes of the atoms in a normal mode to the Raman optical activity(ROA) mode signatures. By fitting with the experimental ROA signatures, we are able to elucidate the scaling parameter which relates the bond polarizability to the electric charge. The result shows that around40% of the charges in pinane are involved in the Raman process under 532 nm laser excitation.

A Left-Handed, Stem-Twining Plant from the Miocene Shanwang Formation of Eastern China

Twining stems of plants are very common in extant tropical and subtropical forests, and the climbing growth habit of plants may be an evolutionary innovation and ecological adaptation to either closed, shady or open, edge environments. However, the origin of handedness in climbing plants remains unclear. Here we report a Miocene (ca. 16 million years ago) macrofossil from the Shanwang Formation of Shandong Province, Eastern China, unequivocally exhibiting the first direct fossil evidence for a left-handed, stem-twining growth habit in plants. This fossil plant bears a thicker, slightly curved supporting stem (2 - 3.5 mm wide), which is loosely, spirally twined by a thinner stem (1.5 - 2 mm wide), possibly representing part of distal branches from a liana or vine.

Left- and Right-Handers May Unintentionally Apply Different Cognitive Strategies in Response to Situational Demands: Study Using the Block-Wise Proportion Congruency Effect

We investigated the effects of handedness on developing latent cognitive response strategies according to situation variables. We used the findings of the block-wise Proportion Congruency (PC) effect in which the proportion of congruent trials in a given block modulates the compatibility effect in its block. The block-wise PC effect cannot be intentionally controlled. A Simon task with three different types of Proportion Congruency (PC) in a given block was used to measure the block-wise PC effects. This task was administered to 24 left-handed and 24 right-handed participants. The reaction time and error rates, consistent with previous studies, demonstrated that the block-wise PC effect was observed in left- and right-handers. Crucially, the block-wise PC effect was more pronounced in left- than right-handers, suggesting that left- and right-handers unintentionally apply different cognitive strategies in response to conflict resolution experiences.

The Behavior of the Hydrogen Atom under Different Potential Well

In this work we studied the behavior of hydrogen atom under different potential well and found that with decreasing the distance between the electron and proton, the more multiple interaction terms start to take effect and the potential well becomes more and more sensitive to the distance between the electron and proton. Based on these results, the potential well for the neutron decaying is determined. Furthermore, the general topics, such as the origin of nuclear energy, the fundamental forces in the nature and the matter with negative mass, also are discussed. At the end of this work, the duality model of our universe is put forth.

英语第四册重点提示及题型释析(2)

6.4 选词填空(1)My teacher is very——.Shealways comes to school on time.

Epidemiology of attention deficit disorder in Brazil: Implications for the Brazilian legal system

In spite of the fact that the legal system adopted in Brazil is codified on the Roman tradition, there is no specific protection in law for people suffering from Attention Deficit Disorder (ADD). In contrast, the law of the United States is largely derived from the common law system and there are two federal laws that guarantee a free appropriate public education and provide services to eligible students with disabilities. They are: Section 504 and Individuals with Disabilities Education Act2. The American Legal System reflects the social demand based on epidemiological studies. In the present investigation, we studied the prevalence of attention disorders in Brazil. The sample included 239 students, rated regarding attention problems with a checklist filled by 45 different teachers. As left-handers show greater problems in the impulsive-hyperactivity domain, we investigated the influence of gender on attention problems using handedness as a covariate. Hand preference was assessed by direct observation. A student was classified into the ADD group if he (she) was rated maximum score in at least six questions concerning impulsivity, hyperactivity, and inattention. Sixty-eight students (28% of the total sample) were included in the ADD group. The percentage of males was found to be greater in ADD group as compared to the percentage of males in the normal-control group. The gender effect was not explained by handedness. Our data is similar with other studies. For instance, the rate of ADD symptoms among indigenous students from the Brazilian Amazon was found to be 24.5%. In Brazilian juvenile offenders, the percentage was 33%. The differences with other studies are discussed considering sampling procedures. In accordance with the tradition of the Roman system, we urgently need Federal specific laws to deal with this public health problem. We must convert into specific laws, the Convention on the Rights of Persons with Disabilities (United Nations) that was recently ratified in Brazil.

MRI and diffusion tensor imaging in assessing correlation of activation of cortical motor function and manifestations of corticospinal tract with muscle strength in patients with ischemic stroke

BACKGROUND： Ischemic stroke is often followed by the abnormalities of neurons and corticospinal tract, which can lead to corresponding clinical symptoms and signs. Recently, with the continuous perfection of high-field MRI instrument, it becomes possible to assess and investigate the cortical function and structural reconstruction following stroke by using MRI and diffusion tensor imaging （DTI）. OBJECTIVE： To observe the cortical motor function and changes of corticospinal tracts by using MRI and DTI in the patients with ischemic stroke at acute period, compare with the normal subjects, and assess the damage of corticospinal tract and muscle strength.DESIGN ： A case-control observation.SETTING： Department of Medical Imaging, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA. PARTICIPANTS ： Nine inpatients （5 males and 4 females） with injury of motor function induced by acute ischemic stroke were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA between August and December in 2005, they aged 16-87 years with an average of 51 years old, and those with obvious conscious disturbances and severe cognitive disorders were excluded. At the same time, nine healthy right-handed physical examinees matched by age and gender with the patients were also selected, and they all had no nervous disease, epilepsy, mental diseases, cerebrovascular abnormalities and injury history, etc. All the subjects were informed with the detected items and agreed to participate in. METHODS： All the 9 patients with ischemic stroke at acute period and 9 healthy subjects were examined with MRI and DTI.① A block-based design was used in the MRI, the passive finger-to-finger exercise was used as the stimulative task, and the static condition was taken as the baseline task. The GE 1.5T MRI system was used, all the data were processed after off-line, and analyzed with the SPM2 software, the association between the activated area and local anatomy of brain was observed. ② The DTI image was processed with the dTV.Ⅱ.R1 software part of the anisotropic image and color anisotropic image were shown, and the three-dimensional white matter image of bilateral corticospinal tracts of the patients were reconstructed. ③ The muscle strength of the affected hand of the stroke patients was judged with the Brunnstorm standard. MAIN OUTCOME MEASURES： The manifestations of MRI, DTI and corticospinal tracts of the 9 stroke patients were mainly observed. RESULTS： All the 9 stroke patients and 9 healthy subjects were involved in the analysis of results. ① Results of MRI examination： The handed exercise of the healthy subjects mainly activated contralateral sensorimotor cortex, posterior parietal cortex and bilateral supplementary motor areas. For the exercise of ipsilateral hand of 7 stroke patients, contralateral sensorimotor cortex was weakly activated, but ipsilateral posterial parietal cortex was obviously activated, and the activation of cerebrum was observed in 3 of them. For the other two patients, bilateral sensorimotor cortexes were activated during the exercise of ipsilateral hand, and the ipsilateral activated area was greater than the controlateral one. The exercise of contralateral hand activated contralateral sensorimotor cortex, posterior parietal cortex and contralateral supplementary motor area, and no obvious ipsilateral activated area was observed.② Results of DTI examination： The anisotropic values of the infarcted area were obviously lower than those of the contralateral part （t=4.570, P 〈 0.01）. the anisotropic value of the infarcted area were obviously was obviously correlated with bilateral muscle strength （t=0.888, P 〈 0.05）. ③ Results of the examination for corticospinal tracts： The reconstruction of bilateral corticospinal tracts, contralateral anatomic form were generally identical with those of normal subjects, the consistency of each continuous form from anterior central gyrus downward to internal capsule to bridge of varolius and bulbus medullae. Because of the involvement of infarcted area to different extent, ipsilateral corticospinal tract was manifested by the interruption of succession and loss of consistency of anatomic structural form. The severity for the injury of corticospinal tract was markedly correlated with the muscle strength of the ipsilateral hand （r=0.888, P 〈 0.05）. CONCLUSION ： ① The MRI manifestations of stroke patients during the exercise of affected hand are different from those of normal subjects, suggesting that there is compensation and reconstruction of brain function.② DTI examination is good for the judgement of the correlation between the damaged severity of infarction and muscle strength.③The damaged severity of corticospinal tracts is correlated with muscle strength, and it can be used to judge the prognosis of rehabilitative treatment.

Magnetic stimulation at Neiguan(PC6) acupoint increases connections between cerebral cortex regions

Stimulation at specific acupoints can activate cortical regions in human subjects.Previous studies have mainly focused on a single brain region.However,the brain is a network and many brain regions participate in the same task.The study of a single brain region alone cannot clearly explain any brain-related issues.Therefore,for the present study,magnetic stimulation was used to stimulate the Neiguan（PC6） acupoint,and 32-channel electroencephalography data were recorded before and after stimulation.Brain functional networks were constructed based on electroencephalography data to determine the relationship between magnetic stimulation at the PC6 acupoint and cortical excitability.Results indicated that magnetic stimulation at the PC6 acupoint increased connections between cerebral cortex regions.

Frame-indifference of cross products,rotations,and the permutation tensor

Under improper transformations,the traditional transformation laws for cross products,the permutation tensor,and rotations are incorrect.For a cross product,using a counter-example the left-hand rule is proved wrong.The unique rule for a cross product is the right-hand rule.Coordinate systems have handedness,while a cross product is frame-indifference.Since the permutation tensor is defined as a triple product including a cross product,the law for the permutation tensor is false.For a rotation,its pseudovector representation is incorrect,because the mirror is an auxiliary device to produce the virtual image rather than a new coordinate system or reference frame.

C_3-Symmetric Molecules with Axial Chirality and Handed Arrangement of Dipole Fields

Introduction Chirality is defined as the absence of inversion symmetry,however,it is actually a pseudo-scalar of objects or figures,and does not depend for its definition on any connection to the physical world[1-5]. Logically,chiral molecules may possess other inherent physical quantity that guarantees the connection to the physical world[6,7].

Parametric analysis of the planar metamaterials based on complementary double-ring resonators

The planar metamaterials comprising complementary double-ring resonators （CDRRs） show its left handed behaviour. As a consequent work, this paper presents a detailed parametric study on the magnetically resonant transmission characteristics of the complementary double-ring metamaterials based on its structural parameters. This will be useful for the design of compact planar metamaterials based on the transmission lines loaded with CDIRRs.