cssi/SciSciGPT-SciSciNet huggingface dataset:
Functional connectivity of hippocampus in temporal lobe epilepsy depends on hippocampal dominance: a systematic review of the literature

Lateralized alterations in hippocampal function in the resting-state have been demonstrated for patients with temporal lobe epilepsy (TLE). However, resting-state fMRI of the hippocampus has yet to be substantiated as an adjunct to standard pre-operative assessments of the seizure focus. Here we report the results of a systematic review of resting-state fMRI studies investigating laterality of hippocampal network connectivity in TLE patients. A search of the PubMed, SCOPUS, Web of Science, and Embase databases for full-length articles written in English was conducted through June 2020 using the following terms: ‘resting state fMRI,’ ‘hippocampus,’ ‘epilepsy,’ and ‘laterality.’ Our literature search yielded a total of 42 papers. After excluding studies that did not include patients with epilepsy, utilize resting-state fMRI, or explore the relationship between functional connectivity and disease lateralization, 20 publications were selected for inclusion. From these studies, a total of 528 patients, 258 with left TLE and 270 with right TLE, and 447 healthy controls were included. Of the 20 studies included, 18 found that patients with TLE demonstrated decreased hippocampal functional connectivity ipsilateral to the epileptogenic focus and 10 additionally reported increased hippocampal functional connectivity contralateral to the epileptogenic focus. Several studies demonstrated that the duration of disease was correlated with these changes in functional connectivity. This implies that a compensatory mechanism may be present in patients with treatment-refractory TLE. The consistency of this hippocampal connectivity pattern across multiple studies suggests resting-state fMRI may be useful as a non-invasive diagnostic tool for preoperative evaluation of TLE patients.
A Census Tract-Level Examination of Differences in Social Determinants of Health Among People With HIV, by Race/Ethnicity and Geography, United States and Puerto Rico, 2017.

ObjectiveSocial and structural factors, referred to as social determinants of health (SDH), create pathways or barriers to equitable sexual health, and information on these factors can provide crit...
Super-Resolution Block-Sparse Channel Estimation Over Uplink M-MIMO 5G Mobile Wireless Networks

In this paper, we develop a novel super-resolution block-sparse channel estimation approach for uplink massive multi-input multi-output (MIMO) based 5G mobile wireless networks. We first introduce a pattern-coupled Bernoulli-Gaussian (PC-BG) prior to characterize block-sparse channels resulting from a small number of scatterers with a small range of angular spread in the angular domain. Then, we propose a Bayesian inference method to infer the channel vector as well as its hyperparameters associated with the PC-BG prior. Specifically, the proposed algorithm is developed within an expectation-maximization (EM) framework and integrated with the generalized approximate message passing (GAMP) technique of approximating the intractable posterior distribution. Finally, instead of adopting some predefined basis/dictionary, such as a discrete Fourier transform (DFT) basis, we propose to learn the offgrid gap between sampled grid-point and true angle of arrivals (AoAs) iteratively for better sparse channel representation, which thus can improve the sparse channel recovery performance. Our numerical analyses validate and evaluate the effectiveness of our proposed scheme.
The Pacific-Atlantic Front in the East Siberian Sea of the Arctic Ocean

It is the purpose of this paper to introduce the reader to the various water masses that are found in the Arctic Ocean and describe how fronts, separating these water masses, are identified through the application of physical and biogeochemical measurements. Variations in the positions/alignments of these fronts help to describe changes in circulation patterns that impact local physical, chemical, and biological systems. In this chapter, the distributions of various physical and geochemical parameters representing summer conditions in the Arctic during 2015, a year of particularly good spatial coverage in terms of scientific observations, will be presented and analyzed with a focus on identifying the front separating Atlantic and Pacific halocline waters in the East Siberian Sea by qualitative means.
Financial Capability: A Conceptual Review, Extension, and Synthesis

Financial capability is an important factor that contributes to consumer financial wellbeing. In the research literature, financial capability has multiple meanings that could refer to financial literacy, financial behavior, financial access, and/or financial outcome, depending on different research purposes and conceptualizations. The purpose of this review is to examine the literature on consumer financial capability with a focus on conceptual definitions. After reviewing 250 research papers on financial capability published in 2007-June 2021 and retrieved from Scopus, five conceptual definitions of financial capability are identified and discussed. Based on the discussion, in this review, financial capability is defined as an individual ability to apply appropriate financial knowledge, perform desirable financial behaviors, and take available financial opportunities for achieving financial wellbeing. A conceptual framework on the antecedents, construct, and outcomes of financial capability is then presented and propositions based on this framework and relevant literatures are proposed. Finally, implications for future research are discussed.
Experimental investigation on cooling of prismatic battery cells through cell integrated features

Abstract Lithium-ion batteries are sensitive to temperature changes over their life. High operational temperatures can negatively affect the battery and lead to capacity fade and lifespan reduction. Air-cooled thermal management systems are widely used in electrified vehicles. A novel air-cooled battery design is introduced. Aluminum fin cooling features are directly integrated onto prismatic cells rather than established by the use of an auxiliary polymer component. When the cells are arranged in a battery array, the on-cell features generate cooling channels. A forced-convection testbed is used to determine thermal management performance. Shear resistance experiments are used to measure the mechanical resistance of the battery cell assemblies. The study demonstrates that a configuration with parallel channel cell-wall integrated fins recovers the performance of the system with the standard polymer space but provides a 20% improvement in temperature uniformity under fan power control. This configuration, however, lacks mechanical resistance in the assembly. A poka-yoke based configuration with tapered channels enhanced by secondary fins provides mechanical resistances and also performs better in both flow and fan power control. This configuration maintains the cell maximum temperature as the assembly via polymer spacers but improves the temperature uniformity by 50%.
Blur Reduction in Ultrasonic Images Using Pseudo Three-Dimensional Wiener Filtering

The ability to quantitatively image material anomalies with ultrasonic methods is severely restricted by the axial and lateral resolution of the interrogating transducer. Axial resolution is controlled by the pulse duration of the transducer with shorter pulse durations yielding better axial resolution. Lateral resolution is controlled by the width of the interrogating beam with narrower beams providing better lateral resolution.
Issues of interaction: keyboarding, word processing and composing

AbstractGiven the increased educational concern and interest in keyboarding and its obvious relationship to word processing and the language arts composition program, this study began to explore questions regarding the interaction of the three—keyboarding, word processing and composing. Specifically, the effect of minimal keyboarding and word processing skills on the composition of fourth grade students was investigated in terms of both the quantity and the syntactic complexity of the writing. The results of data analysis from two classrooms indicate that children’s writing decreases in terms of quantity following a nine week training session. Preliminary data also indicate that this decrease is temporary in nature, and that quantity is recovered following minimal practice time over another nine week period. In fact by April of the school year the fourth graders composing on the computer were producing significantly more writing than their counterparts who were writing by hand. Syntactic complexity did no...
Electron Holography of Ferromagnetic Materials

Electron holography in the transmission electron microscope provides a powerful approach for characterizing nanoscale ferromagnetic materials. By measuring the phase shift of an electron beam that has passed through the magnetic field of the sample, quantitative measurement at the nanometer scale can be achieved. Thus, the technique allows both visualization as well as quantification of magnetic fields with high spatial resolution and sensitivity. Off-axis electron holography is the operating mode that is most commonly used. The theoretical basis and experimental geometry for the technique are described. Representative examples of a range of ferromagnetic materials are then described in more detail. Finally, prospects and problems for future developments are briefly discussed. Keywords: off-axis electron holography; electrostatic biprism; hologram reconstruction; magnetization reversal; magnetic domains; patterned nanostructures
Treatment of Chronic Kidney Disease–Mineral Bone Disorder and Vascular Complications

: Over the last 30 years there have been improvements in our understanding of bone and vascular calcification in kidney disease patients. This has led to the development of new therapeutic strategies that allow more effective control of parathyroid hormone, less positive calcium balance, improved bone remodeling, and less vascular calcification. These changes in our knowledge and available treatments will be discussed.
STATE-OF-THE-ART OF BALLASTLESS TRACK AT-GRADE

Ballastless track support structures are regarded as possible solutions to the problems of track maintenance and the research and development of these structures is reviewed. The new types of structures include ties embedded in concrete slabs and also beams. These structures are cast-in-place, precast, and slip formed. Several design problems are examined with consideration to the advantages of ballastless track over conventional track. Maintenance and cost advantages are considered. Current research and development is considered for seven countries; United States, United Kingdom, Germany, France, Soviet Union, Switzerland, Japan. This paper reviews the types of structures actually built and put in experimental or revenue service. The development of new types of rail fasteners is also considered with each type of new track structure.
Exploiting temporal information in functional magnetic resonance imaging brain data

Functional Magnetic Resonance Imaging(fMRI) has enabled scientists to look into the active human brain, leading to a flood of new data, thus encouraging the development of new data analysis methods. In this paper, we contribute a comprehensive framework for spatial and temporal exploration of fMRI data, and apply it to a challenging case study: separating drug addicted subjects from healthy non-drug-using controls. To our knowledge, this is the first time that learning on fMRI data is performed explicitly on temporal information for classification in such applications. Experimental results demonstrate that, by selecting discriminative features, group classification can be successfully performed on our case study although training data are exceptionally high dimensional, sparse and noisy fMRI sequences. The classification performance can be significantly improved by incorporating temporal information into machine learning. Both statistical and neuroscientific validation of the method’s generalization ability are provided. We demonstrate that incorporation of computer science principles into functional neuroimaging clinical studies, facilitates deduction about the behavioral probes from the brain activation data, thus providing a valid tool that incorporates objective brain imaging data into clinical classification of psychopathologies and identification of genetic vulnerabilities.
Geochemical Impacts of Sequestering Carbon Dioxide in Brine Formations

The purpose of this chapter is to lay out potential geochemical impacts of geologic sequestration. Injection of supercritical carbon dioxide into a brine formation shifts rock-dominated reaction systems to fluid-dominated systems controlled by acid-generating reactions and mixed-fluid equilibria. Increased carbonic acid content in the brine reduces the pH of in situ brine by approximately 1.5―4 pH units, depending on brine chemistry, formation lithology, and temperature, to a pH value between 3.5 and 4. Alkalinity is also produced by reaction of carbonic acid with reservoir minerals, but alkalinity of in situ brine cannot overcome the acidity produced by dissolution of supercritical carbon dioxide fluid. Analysis suggests that displacement of brine as injection proceeds will lead to separation from supercritical carbon dioxide fluid and loss of saturated carbon dioxide, wherein alkalinity can neutralize the acidity, yielding near-neutral to alkaline pH. Silica concentrations and dissolution rates will become enhanced, whereas silica precipitation is inhibited by acidic brine. Acidified brine will also react with both reservoir rock and caprock, enriching the brine in metal cations and creating alkalinity. As silica-supersaturated, metal-laden brine migrates into areas without carbon dioxide, in situ monitoring can be used to indicate repository performance. Return of silica-supersaturated brine to a rock-dominated reaction system buffered to neutral pH conditions may enhance precipitation of quartz, chalcedony, or amorphous silica. Reaction kinetics among supercritical carbon dioxide, brine, and rock are comparable to rates in systems containing gaseous carbon dioxide.
Cultural aspects of substance abuse and alcoholism : assessment and management

Cultures and ethnic groups within cultures prescribe, proscribe, or tolerate use of various psychoactive substances for social or personal purposes. In the United States, these ethnic strictures and practices vary widely. Ethnic enculturation into particular psychoactive substances can either reduce the risk of substance abuse or greatly increase this risk. To function effectively in a multiethnic society, psychiatric physicians of North America should learn to assess the cultural and ethnic dimensions and effects of substance abuse among their patients. In addition, they should be culturally sensitive to those aspects of treatment that can impede or augment successful outcomes. Finally, any and all attempts at primary prevention, early recognition and intervention, and rehabilitation should reflect the complex cultural, political, economic, and religious factors that influence substance use and abuse.
Uncertainty of quantile estimators using the population index flood method

[1] The population index flood (PIF) method is an analytical model that has been recently suggested for regional frequency analysis. In this paper, explicit equations based on Fisher's information are derived for estimating the standard error of at-site quantile estimators for two regional PIF methods utilizing the generalized extreme value distribution with maximum likelihood estimation. These explicit equations are used to calculate the asymptotic gain in using regional frequency analysis as opposed to single site frequency analysis. Simulation experiments for different sized regions and different values of the shape parameter show that the suggested methods for estimating the standard error of at-site quantile estimators give values close to the actual or true values. In addition, similar simulation experiments are also used to test the accuracy of a newly suggested procedure for estimating the standard errors of at-site quantile estimators for the Hosking and Walls regional index flood method. The results of the simulations indicate that these estimated standard errors can in some cases give unreliable results. In general, this study shows that the PIF models are a useful addition to existing regional frequency analysis models. Their analytic structure, which is not present in other regional models, has important theoretical and practical implications.
Providing Scalable Many-to-One Feedback in Multicast Reachability Monitoring Systems

With the deployment of native multicast in commercial networks, multicast is getting closer to becoming a ubiquitous service in the Internet. The success of this deployment largely depends on the availability of goodmanagemen t tools and systems. In this paper, we focus on reachability monitoring as an important multicast management task. First, we provide a general architecture for multicast reachability monitoring systems and focus on three critical functions: agent configuration, monitoring and feedback collection. For each component, we provide a number of alternative approaches to implement the requiredfunctionality and discuss their advantages and disadvantages. Then, we focus on the feedback collection component. To a large extent, it determines the complexity and the overheadof a monitoring system. We compare a number of alternative approaches for feedback collection using simulations andmak e suggestions on when to use each. We expect our work to provide insight into the issues and considerations in designing and developing multicast reachability monitoring systems.
Lexical biases in aphasic sentence comprehension: An experimental and corpus linguistic study

Background: This study investigates the role of lexical information in normal and aphasic sentence comprehension. Effects of verb biases in normal comprehension have been well documented in previous studies (e.g., Spivey-Knowlton & Sedivy, 1995; Trueswell, Tanenhaus, & Kello, 1993), but their role in aphasic language processing has largely been ignored (with the exceptions of Menn et al., 1998, and Russo, Peach, & Shapiro, 1998). Aims: The aim of the study is to test the lexical bias hypothesis, i.e., the hypothesis that sentence comprehension is influenced by lexical biases in aphasic listeners, as well as in normals. Method & Procedures: Using a sentence plausibility judgement task, we probe for sensitivity to verb transitivity bias, i.e., the likelihood, as estimated from corpus counts, that a verb will be transitive, rather than intransitive. Five normal controls and eighteen participants with aphasia (six with Broca's aphasia, four with Wernicke's aphasia, two with conduction aphasia, and six with an...
Role of voltage-gated Na+ and Ca2+ channels in gonadotropin-releasing hormone-induced membrane potential changes in identified rat gonadotropes.

We have previously reported that GnRH induces rhythmic hyperpolarizations in male rat (35- to 45-day-old) gonadotropes by periodically opening apamin-sensitive Ca(2+)-activated K+ channels. Using the whole cell recording technique, we now show that these gonadotropes, identified with the reverse hemolytic plaque assay, express tetrodotoxin-sensitive Na+ channels and omega-conotoxin-insensitive, high voltage-activated Ca2+ channels that are partially sensitive to dihydropyridines. We found no low voltage-activated Ca2+ channels in these cells. At the normal resting potential, about 93% of the Na+ channels and 50% of the Ca2+ channels are inactivated. The GnRH-induced hyperpolarizations transiently remove the resting inactivation of Na+ and Ca2+ channels, enabling them to initiate action potentials at the termination of each hyperpolarization. Opening of Na+ channels accounts for the high rate of rise and the positive peak of the action potential. In addition, a significant fraction of Ca2+ channels should ...
LOW FREQUENCY STREAMFLOW REGIMES OVER THE CENTRAL UNITED STATES: 1939-1998

Intra- to multi-decadal (6-30 year) streamflow regimes over the central United States during the late 20th century are identified and investigated here through a two-stage analysis. The first stage ranks mean annual flow rates during 1939-1998, calculates Mann-Whitney U statistics from samples of those rankings over running time windows, and then tests those U statistics for significance. This analysis of the records of 42 Hydro-Climatic Data Network stations over the Great Plains and Midwest reveals consistent patterns of highly ranked annual streamflow during time windows at the end of the century, with most beginning during the late 1960s and early 1970s and ending in either 1997 or 1998. Many of these stations are located in a critical agricultural region known as the Corn Belt. The second stage of analysis compares both the duration of abnormal flow periods and the frequency of hydrological surplus and drought conditions during the high flow years indicated by the first stage, relative to the remaining years of 1939-1998. Among gage stations in the climatologically drier western Corn Belt during the 1980s and 1990s there is a clear tendency toward extended periods of above normal flow, which results in more than a doubling in the average annual frequency of hydrological surplus days relative to previous years. These stations also show more than a 50% reduction in the average annual frequency of hydrological drought days relative to previous years. Similar but less pronounced shifts in hydrological regime are evident in the central and eastern Corn Belt, and in the Mississippi River at Vicksburg during 1973-1998. These results indicate that many areas of the central United States have shifted toward a climate regime of relative hydrological surplus during the closing decades of the 20th century.
Effects of mental practice and body position on the accuracy of blind visual-kinesthetic positioning.

Ware (2) and Ware and Barnhill (3) have demonstrated that practice alone with indirect subject control and practice with different types of sensory feedback and direct subject control leads to an increase in the perceptual accuracy of intermediate visualkinesthetic position. The research was conducted while the subject was sitting with head tilted or standing. The present study extended practice to include mental practice (1) and to include the supine as well as the standing position. Fifty-two undergraduate psychology students from 18 to 44 yr. of age were randomly assigned to a mental practice or a control condition. Within each condition, half of the students performed in the standing and then the supine position and the others in the opposite order. Details of the apparatus were described earlier (3). The device was 4 ft. in diameter with a double-pointed rod that pivoted in the middle to allow free movement around 360". All students, tested individually, were shown that device. Control students were allowed l0'min. to relax before performing while the other students were guided through 10 min. of mental practice on the device. The students were then blindfolded, and the device was adjusted so the center of the rod was parallel to the base of the sternum. Starting in a standing or supine position, they adjusted the rod randomly to the 12 clock positions. Seventeen practice trials and 12 test trials were given for each of the body positions. Accuracy was measured in degrees discrepancy from the assigned clock positions. The amount of mental practice used here was not effective in significantly increasing blind positioning accuracy. Subsequent research might focus on more mental practice time and actual performance before mental practice. The positioning accuracy for the standing position was, however, significantly better than the supine body position using constant errors (PI,* = 8.00, P < .01), with means and standard deviations, respectively, being M = -2.83, SD = 2.93 and M = -5.08, SD = 2.80. A significant interaction was found between position and trials (&.a = 7.31, P < .01). The difference between the means in the vertical body positions for the practice trials (M = -2.85, SD = 2.36) and the test trials (M = -2.82, SD = 3.17) was minimal, while the difference between the means in the supine position (M = -5.53, SD = 6.28) and (M = -4.62, SD = 4.84) indicates some learning. The unfamiliarity of performing blindfolded plus being in a supine position may have accounted for the significant main effect. Research should test the effect of extended blind training while supine on positioning accuracy.
Continuous Donnan Dialysis Sampler for Flame Atomic Absorption Spectrometry

Donnan dialysis occurs when an ion-exchange membrane separates aqueous solutions of differing ionic composition. A typical dialysis cell for analytical applications is shown in Fig. 1. The ionic strength differential causes transport of analyte ions of the appropriate charge sign from the sample into the receiver electrolyte. If the receiver ionic strength exceeds that of the sample by at least a factor of 100, and if the dialysis is not allowed to approach Donnan equilibrium, the rate of analyte ion transport into the receiver is proportional to the concentration of that ion in the sample and independent of sample matrix factors.
The bilaterally symmetrical deafferentation syndrome in macaques after bilateral spinal lesions: evidence for dysesthesias resulting from brain foci and considerations of spinal pain pathways.

Six macaques had been subjected to chronic left thoracic anterolateral cordotomy, which released persistent self-attacks of the hypoalgesic right hind limb. One to 4 weeks later, lesions were placed in the right thoracic spinal cord, 2–5 segments apart from the left lesion. None of these second-stage spinal lesions, including spinal hemisection, affected the continued self-attacks of the right leg. Therefore, the chronic deafferentation syndrome of contralateral anterolateral cordotomy is not dependent upon the rostral conduction, via long spinal sensory tracts, of neural activity from ipsilateral lumbosacral spinal segments. Furthermore, second-stage right thoracic spinal lesions, which damaged the anterolateral tracts in 4 macaques, caused the release of the deafferentation syndrome in the left hind limb, despite extensive prior destruction of the left anterolateral tracts. Therefore, the release of the deafferentation syndrome by contralateral cordotomy is independent of the functional activity of the ipsilateral anterolateral tracts. The bilateral symmetry of this syndrome after extensive bilateral spinal lesions suggests pathophysiological foci at the level of the brain rather than the spinal cord. This syndrome is considered to be an objective index of disturbing subjective sensations.
Modeling Dynamic Plasticity and Spall Fracture in High Density Polycrystalline Alloys

Abstract The dynamic thermomechanical response of a tungsten heavy alloy is investigated via modeling and numerical simulation. The material of study consists of relatively stiff pure tungsten grains embedded within a more ductile matrix alloy comprised of tungsten, nickel, and iron. Constitutive models implemented for each phase account for finite deformation, heat conduction, plastic anisotropy, strain-rate dependence of flow stress, thermal softening, and thermoelastic coupling. The potentially nonlinear volumetric response in tungsten at large pressures is addressed by a pressure-dependent effective bulk modulus. Our framework also provides a quantitative prediction of the total dislocation density, associated with cumulative strain hardening in each phase, and enables calculation of the fraction of plastic dissipation converted into heat energy. Cohesive failure models are employed to represent intergranular fracture at grain and phase boundaries. Dynamic finite element simulations illustrate the response of realistic volume elements of the polycrystalline microstructure subjected to compressive impact loadings, ultimately resulting in spallation of the material. The relative effects of mixed-mode interfacial failure criteria, thermally-dependent fracture strengths, and grain shapes and orientations upon spall behavior are weighed, with interfacial properties exerting a somewhat larger influence on the average pressure supported by the volume element than grain shapes and initial lattice orientations within the bulk material. Spatially resolved profiles of particle velocities at the free surfaces of the volume elements indicate the degree to which the incident and reflected stress waves are altered by the heterogeneous microstructure.
Impact evaluation in the post-disaster setting: a case study of the 2005 Pakistan earthquake

There is growing interest in impact evaluation in the humanitarian and development sectors. Several recent reports have identified post-disaster impact evaluation (PDIE) as a particular challenge and galvanised interest in pushing the field forward. This paper reviews existing work, synthesises a set of guiding principles and analytic frameworks for PDIE, and applies those to a design for the evaluation of recovery programmes following the 2005 Pakistan earthquake. The paper contributes to ongoing discussions of impact assessment within the humanitarian sector while also introducing impact evaluation practitioners to the challenges of conducting quality impact evaluations in post-disaster settings.
Comparisons of the Dehydroisoandrosterone-Δ5-3β-hydroxysteroid Dehydrogenase and the Δ5-Pregnenolone-Δ5-3β-hydroxysteroid Dehydrogenase Activities of Ovaries of Control, Hemiovariectomized, Gonadotrophin- Treated and “Androgen-Sterilized” Young Rats

Two Δ8-3β-hydroxysteroid dehydrogenase activities of rat ovaries were determined in parallel, using dehydroisoandrosterone and Δ5-pregnenolone as substrates. Ovaries of control rats from 22 to 63 days of age were studied. Ovarian tissues of hemiovariectomized, gonadotrophin-treated and “androgen-sterilized” rats in the same age group were also assayed. Occasional differences were seen in the rates of oxidation of the 2 substrates. These were not consistently obtained when assays were repeated with tissue from different groups of the same kind of rat. (Endocrinology 83: 626, 1968)
Jayson Blair, The New York Times, and Paradigm Repair

This case study focuses on The New York Times's reaction to the Jayson Blair plagiarism/fabrication scandal by examining how the Times explained Blair's failures to uphold standards of newsgathering and its own failure of the editing process. The study uses image restoration and paradigm repair theories to explore how the Times attempted to repair its own image and that of journalism generally, and concludes that the Times demonstrated a more nuanced concept of paradigm repair than earlier research had shown. Although it distanced itself from Blair and emphasized the value of journalistic standards, the Times accepted responsibility for violations of those standards and admitted that the very structure of the news paradigm failed in this case.
Crystal structures of fructose 1,6-bisphosphatase: mechanism of catalysis and allosteric inhibition revealed in product complexes.

Crystal structures of metal−product complexes of fructose 1,6-bisphosphatase (FBPase) reveal competition between AMP and divalent cations. In the presence of AMP, the Zn2+−product and Mg2+−product complexes have a divalent cation present only at one of three metal binding sites (site 1). The enzyme is in the T-state conformation with a disordered loop of residues 52−72 (loop 52−72). In the absence of AMP, the enzyme crystallizes in the R-state conformation, with loop 52−72 associated with the active site. In structures without AMP, three metal-binding sites are occupied by Zn2+ and two of three metal sites (sites 1 and 2) by Mg2+. Evidently, the association of AMP with FBPase disorders loop 52−72, the consequence of which is the release of cations from two of three metal binding sites. In the Mg2+ complexes (but not the Zn2+ complexes), the 1-OH group of fructose 6-phosphate (F6P) coordinates to the metal at site 1 and is oriented for a nucleophilic attack on the bound phosphate molecule. A mechanism is p...
Normal mode responses of linear piezoelectric materials with hexagonal symmetry

Abstract We consider in this paper the dynamic electromechanical responses of linear piezoelectric materials with hexagonal symmetry in the normal mode configuration. In particular, we formulate the coupled transient problem and obtain numerical results to illustrate the nature of the electrical outputs of rectangular specimens of these materials subjected to time dependent mechanical boundary loads.
Atoms, entropy, quanta: Einstein's miraculous argument of 1905

In the sixth section of his light quantum paper of 1905, Einstein presented the miraculous argument, as I shall call it. Pointing out an analogy with ideal gases and dilute solutions, he showed that the macroscopic, thermodynamic properties of high frequency heat radiation carry a distinctive signature of finitely many, spatially localized, independent components and so inferred that it consists of quanta. I describe how Einstein’s other statistical papers of 1905 had already developed and exploited the idea that the ideal gas law is another macroscopic signature of finitely many, spatially localized, independent components and that these papers in turn drew on his first two, “worthless” papers of 1901 and 1902 on intermolecular forces. However, while the ideal gas law was a secure signature of independence, it was harder to use as an indicator that there are finitely many components and that they are spatially localized. Further, since his analysis of the ideal gas law depended on the assumption that the number of components was fixed, its use was precluded for heat radiation, whose component quanta vary in number in most processes. So Einstein needed and found another, more powerful signature of discreteness applicable to heat radiation and which indicated all these properties. It used one of the few processes, volume fluctuation, in which heat radiation does not alter the number of quanta.
II. The Yalta Voting Formula

Toward the close of the San Francisco Conference, Czechoslovakia's Jan Masaryk remarked that his feeling toward the new Charter “was much like that of the father fondly awaiting the birth of a son. The baby finally arrives and it turns out to be a girl. At first the father is somewhat disappointed, but he soon learns to like her just the same.” While the delegates as a whole believed that their work would go down in history as one of the great documents of all times, many no doubt shared Masaryk's view. For when a document as comprehensive as the Charter is framed, no one gets exactly what he wants.The article of the Charter that raised the most controversy at San Francisco and the article that epitomizes the nature of the Organization, perhaps more than any other, is the Yalta formula for voting in the Security Council. So heated did the debate on this issue become that Room 223 in the Veterans Building, where the meetings of Committee III/l were held, was dubbed the “Madison Square Garden” of San Francisco. The frankness and candor with which the delegates exchanged views constitutes, in many respects, a good example of international democracy in action.It is the purpose of this paper to review the action taken at San Francisco with respect to the Yalta voting formula and to point out the relationship of that formula to the special position of the great powers in the new Organization.
Factors affecting cement strains near the tip of a cemented femoral component

Abstract A generic three-dimensional finite-element model of the upper half of the femur containing a cemented femoral stem of a total hip arthroplasty was developed to study those factors influencing cement strains near the tip of a cemented femoral component. This generic model was verified through another three-dimensional finite-element model that had been created based on the precise geometry of a cadaver femur implanted with a contemporary cemented femoral component. This cadaveric femoral reconstruction had been created with strain gauges embedded in the cement mantle and was then loaded under conditions simulating single leg stance and stairclimbing. By use of the cement strains measured experimentally in the cadaver femur, and comparison of them with those obtained from the finite-element model of that cadaver femur, it was possible to establish proper material properties, boundary conditions, and loading conditions for the generic model. The generic model was then modified parametrically to determine those factors that influence the strains occurring within the cement mantle near the tip of a cemented femoral component. These models suggest that the single factor that most adversely influenced peak strains at or near the tip of the prosthesis was a thin cement mantle. This effect was present both when the cement mantle was reduced in thickness and when a similar effect occurred by virtue of a varus or valgus placement of the stem. Factors that decreased the peak cement strains near the tip of the femoral stem included a more flexible stem and thicker cement mantles. This effect of a more flexible stem could be obtained by changing the modulus of the metal implant, by uniformly reducing the thickness of the stem, or by tapering the stem within the same bone geometry. Thicker cement mantles reduced both the axial and the shear strains occurring at the tip of the prosthesis. The presence or absence of a hole in the tip of the prosthesis per se, as for a centralizer, had no significant effect on the peak cement strains seen around the tip of the prosthesis; however, truncating the tip of the prosthesis from a hemisphere to a flat profile, which resulted in a sharp corner at the tip of the prosthesis, produced a 35% increase in cement strains at the tip as a result of a stress concentration effect. Thus, the common way of modifying the tip to have a hole for a centralizer, which involved truncating the tip, increased the cement strains occurring near the tip of the prosthesis.
Quantum coherence in surface-tip transfer of adatoms in AFM/STM

An adiabatic theory has been developed to describe spontaneous transfer of adatoms from a surface to a tip in atomic force microscopy and scanning tunneling microscopy (AFM/STM). It is shown that, at sufficiently low temperatures, the influence of phonon and electron-hole excitations on the transfer process may become so small that coherent transitions of an adatom between the surface and the tip are possible. The adatom tunnels back and forth between the surface and the tip with a definite period that depends on the surface-tip separation. The effect is mainly due to a unique opportunity to vary the tunneling amplitude of the adsorbate by controlling the tip-surface separation distance. Two features contribute to the quantum coherence phenomenon being even more pronounced as compared to that of interstitial hopping in the bulk: (a) the electron density of states at the Fermi level, and (b) the lattice deformations associated with the presence of the adsorbate outside the surface are noticeably smaller than for an interstitial in the bulk. As a result, electron and phonon polaron effects, respectively, which reduce the mobility of the adatom with respect to surface-tip transition, are substantially suppressed at all temperatures. For typical AFM/STM tip velocities and separationmore » distances, the coherent transition rate of chemisorbed hydrogen atoms at temperatures below 10 K for insulators and semiconductors, and below 0.1 K for metals, may not only be comparable with but also exceed the thermally activated (incoherent) transfer rates at room temperature. {copyright} {ital 1998} {ital The American Physical Society}« less
MOLECULAR CLONING OF THE HELODERMIN AND EXENDIN-4 CDNAS IN THE LIZARD : RELATIONSHIP TO VASOACTIVE INTESTINAL POLYPEPTIDE/PITUITARY ADENYLATE CYCLASE ACTIVATING POLYPEPTIDE AND GLUCAGON-LIKE PEPTIDE 1 AND EVIDENCE AGAINST THE EXISTENCE OF MAMMALIAN HOMOLOGUES

Helodermin and exendin-4, two peptides isolated from the salivary gland of the Gila monster,Heloderma suspectum, are approximately 50% homologous to vasoactive intestinal peptide (VIP) and glucagon-like peptide-1 (GLP-1), respectively, and interact with the mammalian receptors for VIP and GLP-1 with equal or higher affinity and efficacy. Immunohistochemical studies suggested the presence of helodermin-like peptides in mammals. To determine whether helodermin and exendin-4 are present in mammals and their evolutionary relationship to VIP and GLP-1, their cDNAs were first cloned from Gila monster salivary gland. Northern blots and reverse transcription-polymerase chain reaction of multiple Gila monster tissues identified ∼500-base pair transcripts only from salivary gland. Both helodermin and exendin-4 full-length cDNAs were ∼500 base pairs long, and they encoded precursor proteins containing the entire amino acid sequence of helodermin and exendin-4, as well as a 44- or 45-amino acid N-terminal extension peptide, respectively, having ∼60% homology. The size and structural organization of these cDNAs indicated that they were closely related to one another but markedly different from known cDNAs for the VIP/GLP-1 peptide family previously identified in both lower and higher evolved species. Cloning of the Gila monster VIP/peptide histidine isoleucine, pituitary adenylate cyclase activating polypeptide, and glucagon/GLP-1 cDNAs and Southern blotting of Gila monster DNA demonstrate the coexistence of separate genes for these peptides and suggests, along with the restricted salivary gland expression, that helodermin and exendin-4 coevolved to serve a separate specialized function. Probing of a variety of rat and human tissues on Northern blots, human and rat Southern blots, and genomic and cDNA libraries with either helodermin- or exendin-4-specific cDNAs failed to identify evidence for mammalian homologues. These data indicate that helodermin and exendin-4 are not the precursors to VIP and GLP-1 and that they belong to a separate peptide family encoded by separate genes. Furthermore, the existence of as yet undiscovered mammalian homologues to helodermin and exendin-4 seems unlikely.
Crystal structure of the lactose operon repressor and its complexes with DNA and inducer.

The lac operon of Escherichia coli is the paradigm for gene regulation. Its key component is the lac repressor, a product of the lacI gene. The three-dimensional structures of the intact lac repressor, the lac repressor bound to the gratuitous inducer isopropyl-β-D-1-thiogalactoside (IPTG) and the lac repressor complexed with a 21-base pair symmetric operator DNA have been determined. These three structures show the conformation of the molecule in both the induced and repressed states and provide a framework for understanding a wealth of biochemical and genetic information. The DNA sequence of the lac operon has three lac repressor recognition sites in a stretch of 500 base pairs. The crystallographic structure of the complex with DNA suggests that the tetrameric repressor functions synergistically with catabolite gene activator protein (CAP) and participates in the quaternary formation of repression loops in which one tetrameric repressor interacts simultaneously with two sites on the genomic DNA.
More Than Money: The Exponential Impact of Academic Technology Transfer

Academic technology transfer in its current form began with the passage of the Bayh–Dole Act in 1980, which allowed universities to retain ownership of federally funded intellectual property. Since that time, a profession has evolved that has transformed how inventions arising in universities are treated, resulting in significant impact to US society. While there have been a number of articles highlighting benefits of technology transfer, now, more than at any other time since the Bayh–Dole Act was passed, the profession and the impacts of this groundbreaking legislation have come under intense scrutiny. This article serves as an examination of the many positive benefits and evolution, both financial and intrinsic, provided by academic invention and technology transfer, summarized in Table 1. Table 1 Summary Table of the Benefits of Academic Technology Transfer Keywords: Technology transfer, Innovation, Bayh–Dole, Commercialization, Start-ups, Technology licensing, Academic innovation INTRODUCTION Technology transfer is defined as “the process of transferring scientific findings from one organization to another for the purpose of further development and commercialization” by the Association of University of Technology Managers (AUTM). This process typically includes sifting for gold (identifying new technology) and knowing what to do with it when you find it (strategies for protection through patents and copyrights, the development of commercialization strategies such as technology development, marketing, and licensing to existing private companies, or the creation of new start-up companies based on the technology) (11).
Interview with Ralph G. Pearson

Abstract The following interview with Ralph Pearson was compiled over a period of days in the Fall of 1997 with the intention of including it with this Coordination Chemistry Reviews Volume on ‘Inorganic Reaction Mechanisms’ planned for publication during the year of Ralph's 80th birthday.
IN VITRO MODULATION OF FILAMENT BUNDLING IN F-ACTIN AND KERATINS BY ANNEXIN II AND CALCIUM

In our preliminary subcellular localization experiment we demonstrated that annexin II co-localized with submembranous actin in subpopulations of both cultured fibroblasts and keratinocytes. To investigate the physical interaction between annexin II and actin at the cell periphery, in vitro reconstitution experiments were carried out with keratins used as a control. Annexin II, isolated by immunoaffinity column chromatography, was found to exist as globular structures measuring 10 to 25 nm in diameter by rotary shadowing, similar to a previous report. We believe that these structures represent its polymeric forms. By negative staining, monomeric annexin II was detectable as tapered rods, measuring 6 nm in length and 1 to 2 nm in diameter. When annexin II was mixed with actin in 3 mM piperazine-N, N-bis-2-ethanesulfonic acid (PIPES) buffer with 10 mM NaCl2, 2 mM MgCl2 and 0.1 mM CaCl2, thick twisting actin bundles formed, confirming previous reports. This bundling was much reduced when calcium was removed. In the presence of 5 mM ethylenediamine tetra-acetic acid (EDTA) in 5 mM tris, pH 7.2, keratins were found to form a network of filaments, which began to disassemble when the chelator was removed and became fragmented when 0.1 mM CaCl2 was added. Keratins under the same conditions did not fragment when annexin II was present. These results suggest that annexin II, in conjunction with Ca2+, may be involved in a flexible system accommodating changes in the membrane cytoskeletal framework at the cell periphery in keratinocytes.
Global existence for a model Boltzmann equation

Abstract We give a global existence proof for a class of inhomogeneous continuous velocity Boltzmann models with stochastic scattering kernels.