cssi/SciSciGPT-SciSciNet huggingface dataset:
Bose-Einstein Gas with Repulsive Interactions: General Theory

The properties of a Bose-Einstein gas with repulsive interparticle interactions are determined at low temperature. It is shown that the contribution to the energy arising from particle excitation with small momentum transfers computed in conventional perturbation theory is divergent, but that this difficulty can be avoided by an alternative procedure. An exact method is developed for dealing with that part of the Hamiltonian which gives rise to the perturbation divergence and an exact solution is obtained. The treatment of the region of large momentum transfers is then carried out by introducing the concept of the scattering length of the interaction. The energy is given by the well-known result of the optical theorem corrected by a series in powers of ${(\ensuremath{\rho}{a}^{3})}^{\frac{1}{2}}$, where $\ensuremath{\rho}$ is the density and $a$ the scattering length. Examination of the processes contributing to the energy shows that 95.8% of the correction of order ${(\ensuremath{\rho}{a}^{3})}^{\frac{1}{2}}$ results from a simple alteration of the perturbation energy denominators which takes into account the interaction energy of excited pairs with the unexcited pairs of the medium. The remaining 4.2% arises from multiple particle excitation. These methods also predict the existence of phonon excitation with phonon energies that are linear in the phonon momentum for small excitation and approach $\frac{{q}^{2}}{2M}$ for large momentum. The detailed consideration of this spectrum forms part of the following paper.The results are compared with the theory of fermion systems with strong interactions, where again the largest correction to the first-order "optical" energy arises from alteration of the two-particle propagator which is required to take into account interactions with the many unexcited particles of the medium. The propagator corrections in the fermion and boson systems are similar except for a characteristic difference arising from the statistics. The theory for bosons is shown to be essentially identical with that given by Brueckner and Levinson in their general formulation of the theory of many-body systems with strong interactions.Systems with attractive but saturating interactions are also considered and some new difficulties are shown to arise which cannot be treated by a straightforward application of the methods of this paper.
Developmental biology: Holding it together in the eye

To form tissues, like cells must clump together. The striking resemblance between one cell aggregate in flies and a cluster of soap bubbles points to a crucial role for surface mechanics in biological pattern formation.
Orthogonal combination of the three visual channels

Abstract The responses of three cone types are differenced and summed by receptive fields reported in electrophysiological studies to form two opponent, or chromatic, and one luminance channel. The responses of these three transformed channels are orthogonally combined at a detector. The spectral sensitivity of the transformed channels is a function of intensity and adaptation; transformation equations are given for threshold and suprathreshold. The channel responses, represented as distance along axes in a vector space, have different temporal and spatial properties, depending upon the characteristics of the receptive fields associated with each axis. Spectral sensitivities, Stiles's π 5 , Guth's data on threshold subadditivity, saturation discrimination and hue discrimination are modeled in the space.
Developing young voluntary readers: The home‐the child‐the school

Abstract The purpose of the article is to discuss factors that foster the development of young voluntary readers. Emphasis is placed upon a review of empirical studies which describe home and school characteristics that encourage voluntary reading. The importance of providing a literacy rich environment in the classroom and of promoting voluntary reading as a regular part of the reading instructional program are emphasized.
Subunit dissociation of Busycon canaliculatum hemocyanin

Abstract The hemocyanin of the channeled whelk, Busycon canaliculatum , is a multisubunit protein with a molecular weight close to 9 ṡ10 6 . The increase in pH above neutrality and the addition of 0–5 M urea and 0–2 M GdnHCl is found to dissociate the whole molecules to half-molecules and smaller dimeric and monomeric fragments of one-tenth and one-twentieth mass of the parent hemocyanin. The molecular weight transitions investigated at constant protein concentration of 5 ṡ 10 −2 g ṡ 1 −1 show no clearly discernible plateau regions, where essentially only half-molecules and one-tenth molecules are present. The ultracentrifugation patterns in much of the dissociation region produced by urea at pH 6.9 suggests the presence of three distinct components consisting of whole molecules, half-molecules and largely one-tenth molecular weight fragments. At pH 8.2 and higher, where whole molecules are largely absent the effects of urea on the dissociation of half-molecules to tenths and tenth-molecules to twentieth molecule was investigated by means of light scattering. Analysis of the urea data based on a decamer to dimer and dimer to monomer scheme of dissociation used in our earlier studies gave apparent estimates of about 90 amino acid groups at the contact areas of the dimers in the half-molecules and 110 groups at the monomer contacts forming the dimers. The latter relatively large estimate of groups suggests that the dissociation of the tenth molecules or dimers must occur by longitudinal splitting of the contact areas along both the folded domains and the connecting chain segments of the twentieth molecules. Circular dichroism, absorbance and viscosity data suggest that the secondary structure and conformation of the folded domains of the hemocyanin subunits are largely retained at both high pH and in 3–8 M urea solutions. The molecular weights at pH 9.0–10.6 and in 3–8 M urea are found to be (4.2–4.7) ṡ 10 5 , close to one-twentieth of the mass of the parent hemocyanin. Denaturation and unfolding of the subunit domains is observed between 3 and 6 M GdnHCl solutions, as evidenced by the abolition of the characteristic copper absorbance in the neighborhood of 346 nm and the relatively pronounced changes in circular dichroism at 222 nm and intrinsic viscosity. The further decrease in molecular weights to about (2.6–3.2) ṡ 10 5 , below one-twentieth of the mass of hemocyanin suggests the presence of hidden breaks or scissions in the polypeptide chains suffered during isolation, which become exposed as a result of complete unfolding in GdnHCl solutions. Studies by other investigators have shown that the molluscan hemocyanins are extremely susceptible to proteolysis during the process of isolation.
The Heat Is On: An Inquiry-Based Investigation for Specific Heat

A substantial number of upper-level science students and practicing physical science teachers demonstrate confusion about thermal equilibrium, heat transfer, heat capacity, and specific heat capaci...
Reflections on War and Peace

Suganami, Hidemi, On the Causes of War Kagan, Donald, On the Origins of War and the Preservation of Peace
Mercury-204 Determination by Emission Spectroscopy

The determination of mercury-204 was made by using the isotope shift of the 3984 A mercury line excited by electrodeless discharge. Densitometric traces were made from film recordings of the 3984 A line and the areas under the component peaks were determined. Ratios of each of these areas to the sum of the areas from all the line com-components are plotted against the isotope concentration to produce a working curve. The coefficient of variation for this method is approximately 11 percent The time required for a single determination (after fabrication of the discharge lamp) is about two hours.
Abnormal Overvoltages Caused by Transformer Magnetizing Currents in Long Transmission Lines

As power-transmission distances have increased, new problems, both technical and economic have been encountered, analyzed, and taken into consideration in the design and operation of power systems. As transmission distances continue to increase it is logical to expect that in addition to the already exposed problems, new ones may arise which previously have not required consideration. It is the purpose of this paper to present an analysis of a technical problem which falls in the latter category.
The compression hypothesis and temporal resource partitioning.

Abstract Contingency models of feeding compare the energy per unit time gained from utilizing a resource unit of a particular kind (food types, habitat patches, time periods) against that energy/time expected if the unit is skipped. Optimally, an animal should reject the particular unit if and only if the former energy/time is less than the latter. Consequently, food or habitat types should be excluded if the prospect of finding and consuming better types is sufficiently high. In contrast, feeding periods should be skipped only if it is less costly to wait than to feed. In situations of high food abundance, contingency models imply that animals should be maximally specialized with respect to food or habitat type, but maximally generalized with respect to time period. As food decreases in abundance, food and habitat types should be added to the diet or itinerary, but time periods should be omitted from feeding activity. In contrast, animals with fixed caloric intake should broaden diet, habitat, and feeding times as abundance decreases. According to contingency models, competitors cannot cause item kinds to be dropped from the diet, but because they can affect the values of patches once found, can cause habitat kinds to be dropped from the itinerary. Competitors also reduct the value of feeding during particular time periods, but ordinarily fairly severe depletion must occur before it is optimal to feed no longer in a period frequented by competitors. These arguments imply that temporal resource partitioning on a diel basis should be relatively rare. In fact, specialization according to feeding period should differentially occur in animals of limited abilities to use or process available food, whereas that need not be the case for food-type or habitat specialization. It should also occur in animals sensitive to and found in variable climates.
One-dependent cycles and passage times in stochastic Petri nets

The lengths of certain passage-time intervals (random time intervals) in stochastic Petri nets correspond to delays in computer, communication, manufacturing, and transportation systems. Simulation is often the only available means for analyzing a sequence of such lengths. It is sometimes possible to obtain meaningful estimates for the limiting average delay indirectly, that is, without measuring lengths of individual passage-time intervals. For general time-average limits of a sequence of delays, however, it is necessary to measure individual lengths and combine them to form point and interval estimates. We consider sequences of delays determined by marking changes of the net and use a sequence of random vectors, called start vectors, to provide the link between the starts and terminations of individual passage-time intervals. This method of start vectors for measuring delays avoids the need for additional places and transitions to "tag" entities in the system. We show that whenever the marking process of a stochastic Petri net has a recurrent single-state, the sample paths of any sequence of delays can be decomposed into one-dependent, identically distributed cycles. We then show that an extension of the regenerative method for analysis of simulation output can be used to obtain meaningful point estimates and confidence intervals for time-average limits. This estimation procedure is valid not only when there are no ongoing passage times at any regeneration point but, unlike previous methods, also when the sequence of delays does not inherit regenerative structure. Application of these methods to simulation of a manufacturing flow-line with a shunt bank is discussed.
Lateral Symbiont Acquisition in a Maternally Transmitted Chemosynthetic Clam Endosymbiosis

Deep-sea clams of the family Vesicomyidae live in symbiosis with intracellular chemosynthetic bacteria. These symbionts are transmitted maternally (vertically) between host generations and should therefore show a pattern of genetic variation paralleling that of the cotransmitted host mitochondrion. However, instances of lateral (nonvertical) symbiont acquisition could still occur, thereby decoupling symbiont and mitochondrial phylogenies. Here, we provide the first evidence against strict maternal cotransmission of symbiont and mitochondrial genomes in vesicomyids. Analysis of Vesicomya sp. mt-II clams from hydrothermal vents on the Juan de Fuca Ridge (northeastern Pacific) revealed a symbiont phylotype (designated symB VII ) highly divergent from previously described symbionts of the same host lineage. SymB VII -hosting clams occurred at low frequency (0.02) relative to individuals hosting the dominant symbiont phylotype. Phylogenetic analysis of 16S rRNA genes from a wide range of symbionts and free-living bacteria clustered symB VII within the monophyletic clade of vesicomyid symbionts. Further analysis of 3 symbiont loci (23S, dnaK, and soxA) across 11 vesicomyid taxa unambiguously placed symB VII as sister to the symbiont of a distantly related host lineage, Vesicomya sp. from the Mid-Atlantic Ridge (98.9% median nucleotide identity across protein-coding loci). Using likelihood and Bayesian model discrimination methods, we rejected the strict maternal cotransmission hypothesis by showing a significant decoupling of symbiont and host mitochondrial (COI and mt16S genes) phylogenies. Indeed, decoupling occurred even when symB VII was excluded from phylogenetic reconstructions, suggesting a history of host switching in this group. Together, the data indicate a history of lateral symbiont transfer in vesicomyids, with symB VII being the most conspicuous example. Interpreted alongside previous studies of the vesicomyid symbiosis, these results suggest a mixed mode of symbiont transmission characterized by predominantly vertical transmission punctuated with instances of lateral symbiont acquisition. Lateral acquisition may facilitate the exchange of genetic material (recombination) among divergent symbiont lineages, rendering the evolutionary history of vesicomyid symbiont genomes much more complex than previously thought.
A Generalized Model for Predicting Load-Extension Properties of Woven Fabrics

A method to predict the load-extension behavior of woven fabrics is proposed. Kawabata et al.'s finite deformation theory, which predicts load-extension properties of plain weave and 2/2 twill fabrics in terms of fabric construction parameters and yarn tensile properties, is the basis for the study. The model is generalized to predict the load-elongation behavior of any weave by introducing a parameter that characterizes the interlacing point distribution pattern of the weave. Using the biaxial and uniaxial strain modes, the load-deformation curves over an entire range of strains can be generated. The model applies to woven structures of different degrees of openness, of which the fabric jamming condition is an extreme case.
Contrasting patterns of X/Y polymorphism distinguish Carica papaya from other sex-chromosome systems

The sex chromosomes of the tropical crop papaya (Carica papaya) are evolutionarily young and consequently allow for the examination of evolutionary mechanisms that drive early sex chromosome divergence. We conducted a molecular population genetic analysis of four X/Y gene pairs from a collection of 45 wild papaya accessions. These population genetic analyses reveal striking differences in the patterns of polymorphism between the X and Y chromosomes that distinguish them from other sex chromosome systems. In most sex chromosome systems, the Y chromosome displays significantly reduced polymorphism levels, whereas the X chromosome maintains a level of polymorphism that is comparable to autosomal loci. However, the four papaya sex-linked loci that we examined display diversity patterns that are opposite this trend: the papaya X alleles exhibit significantly reduced polymorphism levels, whereas the papaya Y alleles maintain greater than expected levels of diversity. Our analyses suggest that selective sweeps in the regions of the X have contributed to this pattern while also revealing geographically restricted haplogroups on the Y. We discuss the possible role sexual selection and/or genomic conflict have played in shaping the contrasting patterns of polymorphism found for the papaya X and Y chromosomes.
A system for force distribution measurement beneath the feet

Objective methods for assessing the performance of the postural control system may be helpful in identifying persons with an increased risk of falling. Postural performance is often characterized using center of pressure, but force distribution under the feet may provide additional information on the state of the postural control system. Foot position and orientation can also be extracted from force distribution without the need for manually tracing footprints. A low-cost force distribution measurement system is being developed to complement an existing dual force-plate platform. The system's sensing module contains 1024 1-cm by 1-cm force sensing resistors (FSRs). Interface electronics were designed to convert the FSR outputs to digital data. Continuously sampling the FSR outputs allows one to monitor force distribution over time. A system controller mediates the data acquisition process and transfers the result to a PC for post processing. An apparatus was developed to calibrate the FSRs in order to reduce error caused by inter-sensor variability. Although the system is still under development, preliminary tests show that the system can quantitatively measure force distribution beneath the feet.
Continuum mathematical modeling of slip weakening in geological systems

[1] We describe a framework for mathematical modeling of slip weakening in an initially intact rock mass due to shear strain localization along any arbitrary slip plane. The modeling technique considered is based on continuum mechanics and may be cast directly into a standard nonlinear finite element algorithm for the analysis of prefailure and postfailure responses of geological systems in a boundary value problem. The prefailure behavior is represented by a continuum constitutive model; the postfailure behavior is characterized by frictional yielding on a slip surface with state- and velocity-dependent coefficient of friction. In the context of finite element analysis, slip planes are represented by an embedded strong discontinuity introduced into an initially intact finite element to signal the beginning of postfailure behavior. This paper focuses on the narrow time interval of slip weakening, from the moment the strong discontinuity has been embedded into a finite element until the relative slip has grown to a large enough value for the coefficient of friction to reach steady state. To this end, we formulate a linear slip weakening constitutive law in which the weakening component decays to zero at the same time that the frictional component increases to its value at residual state.
Developing Service-Based Software Systems with QoS Monitoring and Adaptation

The rapid adoption of SOA in many large-scale distributed applications requires the development of adaptive service-based software systems (ASBS), which have the capability of monitoring the changing system status, analyzing and controlling tradeoffs among multiple QoS features, and adapting its service configuration to satisfy multiple QoS requirements simultaneously. In this paper, a performance-model-oriented approach to developing ASBS is presented. This approach consists of the establishment of performance models for SBS through controlled experiments, the development of QoS monitoring and adaptation (M/A) modules based on the performance models, and the validation of ASBS design through simulations. In our approach, four QoS features: timeliness, throughput, accuracy and security, which are important for many critical applications, are considered.
Spectrum Markets and Sharing via Spectrum Consumption Models

The continuous development of new technologies and uses for wireless radio spectrum has prompted spectrum management agencies and wireless service providers to consider flexible spectrum assignment mechanisms as a means to be able to respond in the near future to the changing spectrum management landscape. The regulatory, technological and economic changes that are now driving the wireless services industry will spawn new technical and business models in wireless service provision, many of which will rely on Dynamic Spectrum Access (DSA) methods to enable efficient use of spectrum resources. However, the use of DSA methods also requires using policy-based mechanisms in radio devices to facilitate and control the assignment of spectrum given the wide range of communication scenarios in which there may be conflicting goals for the use of this resource (e.g. public safety vs. profit-based services).Spectrum consumption modeling attempts to capture spectral, spatial, and temporal consumption of spectrum of any specific transmitter, receiver, system, or collection of systems. The information contained in the models enable better spectrum management practices and allows for the identification of spectrum reuse opportunities. The characteristics and structure of spectrum consumption models are being standardized within the newly formed IEEE P1900.5.2 group in which the authors participate.Spectrum consumption models (SCM) allow for a fine grained management of spectrum resources in spectrum sharing and market scenarios. This paper presents and discusses our research in establishing a techno-economic framework for the use of SCM to enable spectrum sharing markets. We focus on exchange based spectrum trading markets where the entities wanting to use spectrum resources (spectrum users) make use of SCMs to express the characteristics of their desired spectrum use and based on them a spectrum exchange entity can determine the range of frequencies within the service area that can satisfy a particular requesting entity’s demand and the charge that it should pay. Several trading scenarios and criteria are also explained. We also discuss the use of SCMs and their integration with Policy-based spectrum management in the context of standardization efforts ongoing in IEEE and the WinForum. We hope that the results and insights of this paper are of use to regulators and policy makers and that it provides them an initial exposure to the potential uses of Spectrum Consumption Models and policy-based spectrum management.
Decentralized Schemes for Size Estimation in Large and Dynamic Groups

Large-scale and dynamically changing distributed systems such as the grid, peer-to-peer overlays, etc., need to collect several kinds of global statistics in a decentralized manner. In this paper, we tackle a specific statistic collection problem called group size estimation, for estimating the number of non-faulty processes present in the global group at any given point of time. We present two new decentralized algorithms for estimation in dynamic groups, analyze the algorithms, and experimentally evaluate them using real-life traces. One scheme is active: it spreads a gossip into the overlay first, and then samples the receipt times of this gossip at different processes. The second scheme is passive: it measures the density of processes when their identifiers are hashed into a real interval. Both schemes have low latency, scalable per-process overheads, and provide high levels of probabilistic accuracy for the estimate. They are implemented as part of a size estimation utility called PeerCounter that can be incorporated modularly into standard peer-to-peer overlays. We present experimental results from both the simulations and PeerCounter, running on a cluster of 33 Linux servers
Hyperglycemia Reduces Proteoglycan Levels in Tendons

Rationale: Diabetic tendinopathy is characterized by increased stiffness, thickness, and excess calcification of affected tendons. We investigated the hypothesis that proteoglycans (PGs), as key regulators of tendon structure and calcification, are altered in diabetic tendons.Methods: Adult porcine patellar tendons were incubated in iso-osmolar media with high or normal glucose levels for 2 weeks. The PG fraction was isolated and analyzed. Protein and mRNA levels of five PGs were measured. PG production was assessed in primary tenocyte monolayers by 35S-sulfate labeling in high and normal glucose conditions with and without exposure to advanced glycation end-products (AGEs). Levels of transforming growth factor β, which commonly mediates some effects of hyperglycemia, were also measured and the effects of free radical scavengers on 35S-sulfate incorporation were determined.Results: PG levels were significantly decreased in tendons exposed to high glucose media compared with tendons in iso-osmolar control ...
Does cytokine signaling link sphingolipid metabolism to host defense and immunity against virus infections

Sphingosine 1-phosphate (S1P)-metabolizing enzymes regulate the level of bioactive sphingolipids that have curative potential. Recently, S1P-metabolizing enzymes such as sphingosine kinase 1 and S1P lyase were shown to regulate influenza virus replication and the virus-induced cytopathogenicity. The mechanism appeared to employ a JAK/STAT type I interferon signaling pathway that induces anti-viral status. Further, sphingosine analogs altered cytokine responses upon influenza virus infection. This article focuses on recent discoveries about the sphingolipid system that influences on host protection from viral virulence and the involvement of cytokine signaling in its underlying mechanisms. Deciphering the steps of this pathway could help us envision how the modulation of sphingolipid metabolism can be applied as a therapeutic approach to overcome infectious diseases.
An Analysis of Country-Related Determinants Influencing Consumer Receptivity of Foreign Products

Attempting to provide insight regarding consumers’ perceptions of and purchase intentions toward foreign products, this study develops and empirically tests an inclusive model containing key determinants that affect this process. A sample of 434 university students from the United States were recruited for the study and multivariate analysis was used to assess the hypothesized effects of key country-related variables upon the stages of consumer decision-making (i.e., product evaluation, attitude formation, and purchase intention) prior to the actual purchase of a foreign product. While country-of-origin image is shown to have influence across all three stages, animosity only affects the consumer’s willingness to buy the foreign product. There is evidence that consumer ethnocentrism influences both the attitude formation as well as the willingness to buy stages. These research findings suggest that marketers should take these three country-related variables under consideration when formalizing a strategy to enter a foreign market with their products. The display of packaging information must also be considered with regards to the consumer’s sensitivities towards the product’s country of origin.
Neuromagnetic evidence for the timing of lexical activation: An MEG component sensitive to phonotactic probability but not to neighborhood density

Evidence from electrophysiological measures such as ERPs (event-related potentials) and MEG (magnetoencephalography) suggest that the first evoked brain response component sensitive to stimulus properties affecting reaction times in word recognition tasks occurs at 300-400 ms. The present study used the stimulus manipulation of Vitevich and Luce (1999) to investigate whether the M350, an MEG response component peaking at 300-400 ms, reflects lexical or postlexical processing. Stimuli were simultaneously varied in phonotactic probability, which facilitates lexical activation, and in phonological neighborhood density, which inhibits the lexical decision process. The present results indicate that the M350 shows facilitation by phonotactic probability rather than inhibition by neighborhood density. Thus the M350 cannot be a postlexical component.
Evidence of Schizophrenia Patients' Reduced Perceptual Biases in Response to Emotion Chimera

The goal of the study was to determine whether dextral individuals with schizophrenia display atypical perceptual biases in response to faces in general, or whether they display atypical perceptual biases in response to emotional facial cues. To this end, we assessed perceptual processing in schizophrenia patients with four types of free-vision chimeric stimuli. Perceptual biases were evaluated in 45 schizophrenia patients and in 46 controls using two face (emotion, gender) tasks and two nonface (dots, gradients) tasks. In response to the emotion chimera, the patients with schizophrenia displayed a reduced left perceptual bias. The two groups did not differ significantly in their response to the gender chimera or to the two nonface chimera. These findings are consistent with the assertion that schizophrenia patients have impaired emotional perception. In the discussion we consider possible reasons for schizophrenia patients' difficulty comprehending emotional facial stimuli. We suggest that schizophrenia patients' reduced perceptual bias in response to the emotion chimera reflects a hypothesized affective information-processing deficit.
Element‐free Galerkin methods

An element-free Galerkin method which is applicable to arbitrary shapes but requires only nodal data is applied to elasticity and heat conduction problems. In this method, moving least-squares interpolants are used to construct the trial and test functions for the variational principle (weak form); the dependent variable and its gradient are continuous in the entire domain. In contrast to an earlier formulation by Nayroles and coworkers, certain key differences are introduced in the implementation to increase its accuracy. The numerical examples in this paper show that with these modifications, the method does not exhibit any volumetric locking, the rate of convergence can exceed that of finite elements significantly and a high resolution of localized steep gradients can be achieved. The moving least-squares interpolants and the choices of the weight function are also discussed in this paper.
Affective Self-Disclosure in Telephone Versus Face To Face Interviews

This study investigated whether Ss were as willing to express their feelings over the telephone as in face to face interviews. Eighty experimental interviews between 160 strangers were conducted under a fixed model 2 × 2 × 2 factorial design. The factors investigated were: (a) interview mode, i.e., telephone vs. face to face; (b) sex of interviewee; and (c) sex of interviewer. Three-way analysis of variance showed no significant differences in the mean number of interviewees' total self-references, affective self-references, or the ratio of affective to total self-references (ASR/TSR) between the two interview modes. Highly statistically significant F ratios were found for differences between male and female interviewees on the three variables: females made more self-references, more affective self-references, and had a higher ASR/TSR ratio than males. Possible explanations for these findings are discussed and replication using actual therapy interviews is urged.
Immunofluorescence localization of the tubulin cytoskeleton during cell division and cell growth in members of the Coleochaetales (Streptophyta)

Study of charophycean green algae, including the Coleochaetales, may shed light on the evolutionary history of characters they share with their land plant relatives. We examined the tubulin cytoskeleton during mitosis, cytokinesis, and growth in members of the Coleochaetales with diverse morphologies to determine if phragmoplasts occurred throughout this order and to identify microtubular patterns associated with cell growth. Species representing three subgroups of Coleochaete and its sister genus Chaetosphaeridium were studied. Cytokinesis involving a phragmoplast was found in the four taxa examined. Differential interference contrast microscopy of living cells confirmed that polar cytokinesis like that described in the model flowering plant Arabidopsis occurred in all species when the forming cell plate traversed a vacuole. Calcofluor labeling of cell walls demonstrated directed growth from particular cell regions of all taxa. Electron microscopy confirmed directed growth in the unusual growth pattern of Chaetosphaeridium. All four species exhibited unordered microtubule patterns associated with diffuse growth in early cell expansion. In subsequent elongating cells, Coleochaete irregularis Pringsheim and Chaetosphaeridium globosum (Nordstedt) Klebahn exhibited tubulin cytoskeleton arrays corresponding to growth patterns associated with tip growth in plants, fungi, and other charophycean algae. Hoop-shaped microtubules frequently associated with diffuse growth of elongating cells in plants were not observed in any of these species. Presence of phragmoplasts in the diverse species studied supports the hypothesis that cytokinesis involving a phragmoplast originated in a common ancestor of the Coleochaetales, and possibly in a common ancestor of Charales, Coleochaetales, Zygnematales, and plants.
Compact Performance Models and Comparisons for Gigascale On-Chip Global Interconnect Technologies

The on-chip global interconnect with conventional Cu/low-k and delay-optimized repeater scheme faces great challenges in the nanometer regime owing to its severe performance degradation. This paper describes the analytical models and performance comparisons of novel interconnect technologies and circuit architectures to cope with the interconnect performance bottlenecks. Carbon nanotubes (CNTs) and optics-based interconnects exhibit promising physical properties for replacing the current Cu/low-k-based global interconnects. We quantify the performance of these novel interconnects and compare them with Cu/low-k wires for future high-performance integrated circuits. The foregoing trends are studied with technology node and bandwidth density in terms of latency and power dissipation. Optical wires have the lowest latency and power consumption, whereas a CNT bundle has a lower latency than Cu. The new circuit scheme, i.e., "capacitively driven low-swing interconnect (CDLSI)," has the potential to effect a significant energy saving and latency reduction. We present an accurate analytical optimization model for the CDLSI wire scheme. In addition, we quantify and compare the delay and energy expenditure for not only the different interconnect circuit schemes but also the various future technologies, such as Cu, CNT, and optics. We find that the CDLSI circuit scheme outperforms the conventional interconnects in latency and energy per bit for a lower bandwidth requirement, whereas these advantages degrade for higher bandwidth requirements. Finally, we explore the impact of the CNT bundle and the CDLSI on a via blockage factor. The CNT shows a significant reduction in via blockage, whereas the CDLSI does not help to alleviate it, although the CDLSI results in a reduced number of repeaters due to the differential signaling scheme.
THE FAST PROTEIN FOLDING PROBLEM

▪ Abstract During protein folding, many of the events leading to secondary and tertiary structure occur in milliseconds or faster. Modern nuclear magnetic resonance and laser detection techniques, coupled with fast initiation of the folding reaction, are probing these events in great detail. Theory, ranging from analytical models to molecular dynamics calculations, is beginning to match up with experiment. As a result, timescales, from such elementary steps as the addition of a residue to a helix to strange kinetics of collapsing protein backbones, can now be measured and interpreted.
Flexible risk metrics for identifying and monitoring conservation-priority species

Abstract Region-specific conservation programs should have objective, reliable metrics for species prioritization and progress evaluation that are customizable to the goals of a program, easy to comprehend and communicate, and standardized across time. Regional programs may have vastly different goals, spatial coverage, or management agendas, and one-size-fits-all schemes may not always be the best approach. We propose a quantitative and objective framework for generating metrics for prioritizing species that is straightforward to implement and update, customizable to different spatial resolutions, and based on readily available time-series data. This framework is also well-suited to handling missing-data and observer error. We demonstrate this approach using North American Breeding Bird Survey (NABBS) data to identify conservation priority species from a list of over 300 landbirds across 33 bird conservation regions (BCRs). To highlight the flexibility of the framework for different management goals and timeframes we calculate two different metrics. The first identifies species that may be inadequately monitored by NABBS protocols in the near future (TMT, time to monitoring threshold), and the other identifies species likely to decline significantly in the near future based on recent trends (TPD, time to percent decline). Within the individual BCRs we found up to 45% (mean 28%) of the species analyzed had overall declining population trajectories, which could result in up to 37 species declining below a minimum NABBS monitoring threshold in at least one currently occupied BCR within the next 50 years. Additionally, up to 26% (mean 8%) of the species analyzed within the individual BCRs may decline by 30% within the next decade. Conservation workers interested in conserving avian diversity and abundance within these BCRs can use these metrics to plan alternative monitoring schemes or highlight the urgency of those populations experiencing the fastest declines. However, this framework is adaptable to many taxa besides birds where abundance time-series data are available.
PLUNGING WAVE PRESSURES ON A SEMI-CYLINDRICAL TUBE

Laboratory tests were made on a 6-inch diameter semi-cylindrical tube simulating a prototype concrete structure designed to be placed parallel to the coastline in the surf zone to intercept offshore transport of beach materials and thus preserving the beach The model beach was of fixed bed type with a slope of 1 to 15 The crest elevation of the tube was set at the still water level for most of the test runs and the sloping beach intersected a flat channel bottom at a depth of 20 75".
Trends in the Kenya Ministry of Agriculture and Livestock Recurrent Cost Budget, 1980-88

The Harvard Institute for International Development provided consulting to government ministries in Kenya during the Daniel Arap Moi regime. This report was one of several that were prepared during that multi-year consultancy. It should be understood in the context of Kenya's development as a pluralistic country, and reveals the struggle to provide government services while attending to the pressures of regional constituencies.
Abstract WP131: Correlation of Cardiac Derangement in Patients with Right-Sided Ischemic Stroke and the Severity of Insular Damage

Objective: Although it is known that neurogenic cardiac damage can occur after an ischemic stroke, the mapping of the neuroanatomic correlation of ischemic stroke-related myocardial injury remains to be defined. Our previous animal study found a higher incidence of myocardial damage from left-sided insular infarction comparing to the right side. However, the results from various clinical studies have been inconclusive. This clinical study aims to identify a quantitative correlation between adverse cardiac outcomes and insular infarction, left-sided versus right-sided, as well as potential prognostic factors that may be used to aid in assessing patient outcomes and making treatment decisions. Methods and Results: A serial measurements of cardiac troponin T (cTnT) and creatine phosphokinase-MB (CK-MB), 12-lead EKG, and two- dimensional echocardiography were performed in 42 patients with MRI-confirmed ischemic stroke involving the insular cortex. The severity of insular damage was measured with diffusion-weighted imaging studies (DWI). Patients with renal failure, recent cardiac ischemic events, or congestive heart failure were excluded. Twenty-two patients (52.4%) had left-sided middle cerebral artery (MCA) infarcts with insular involvement, whereas 20 (47.6%) had a right-sided MCA infarcts involving the insular cortex. When compared to patients with left MCA infarcts involving the insular cortex, patients with right MCA infarcts with insular involvement had significantly higher levels of cTnT elevation. By using the linear regression analysis we also identified a statistically significant correlation between cTnT elevation and severity of right insular damage, instead of the NIH stroke score (NIHSS) as commonly assumed. Moreover, two patients were found to have transient left ventricular wall hypokinesis which mimics Takotsubo cardiomyopathy. Conclusions: This study showed that patients with right MCA ischemic stroke involving the insular cortex, comparing to those with left-sided insular stroke, tend to have more severe cardiac insult leading to higher levels of cTnT. The study also identified severity of insular damage as a potential prognostic factor in assessing cardiac derangement as a complication of insular infarction.
Brain in situ hybridization maps as a source for reverse-engineering transcriptional regulatory networks: Alzheimer's disease insights

Microarray data have been a valuable resource for identifying transcriptional regulatory relationships among genes. As an example, brain region-specific transcriptional regulatory events have the potential of providing etiological insights into Alzheimer Disease (AD). However, there is often a paucity of suitable brain-region specific expression data obtained via microarrays or other high throughput means. The Allen Brain Atlas in situ hybridization (ISH) data sets (Jones et al., 2009) represent a potentially valuable alternative source of high-throughput brain region-specific gene expression data for such purposes. In this study, Allen Brain Atlas mouse ISH data in the hippocampal fields were extracted, focusing on 508 genes relevant to neurodegeneration. Transcriptional regulatory networks were learned using three high-performing network inference algorithms. Only 17% of regulatory edges from a network reverse-engineered based on brain region-specific ISH data were also found in a network constructed upon gene expression correlations in mouse whole brain microarrays, thus showing the specificity of gene expression within brain sub-regions. Furthermore, the ISH data-based networks were used to identify instructive transcriptional regulatory relationships. Ncor2, Sp3 and Usf2 form a unique three-party regulatory motif, potentially affecting memory formation pathways. Nfe2l1, Egr1 and Usf2 emerge among regulators of genes involved in AD (e.g. Dhcr24, Aplp2, Tia1, Pdrx1, Vdac1, and Syn2). Further, Nfe2l1, Egr1 and Usf2 are sensitive to dietary factors and could be among links between dietary influences and genes in the AD etiology. Thus, this approach of harnessing brain region-specific ISH data represents a rare opportunity for gleaning unique etiological insights for diseases such as AD.
ADAPTIVE ZONES AND THE ORDERS OF MAMMALS.

The therian mammals, marsupials and placentals with their ancestors, are an adaptively diverse group as well as a familiar one. Both their phylogeny and functional morphology are better known than those of any other higher taxon of organisms, so they are a paradigm for evolutionary systematics. This is not to say that more or less everything important is known about either their phylogeny or functional morphology, merely that our knowledge is less incomplete for therians than for other groups. In the present paper I revise the concept of adaptive zone and apply the result to the orders of therian mammals. I have omitted some obvious qualifications that are well known in ecology or mammalogy and that do not affect the main argument, e.g. food must be available. There are also exceptions to my generalizations; any naturalist can give his own. I have omitted these except where they seem to exemplify an interesting class.
What Is the Matter with History

"What's the Matter with History?" newspaperman-turned-historian Allan Nevins asked plaintively in the Saturday Review of February 4, 1939. And he went on to answer his question by linking "the present crippled gait of history" and its lack of "a really wide reading public" to the emergence of an overly specialized academic historical literature. Forty-five years later, Thomas Bender has eloquently renewed Nevins's lament, echoing his concern about the fragmentation of historical scholarship, the problem of historical narrative, and especially the failure of historians to reach beyond their "professional peers."1 Bender, however, offers a much more complex and theoretically sophisticated solution than Nevins to the "crisis" of history, to what he calls "the declining significance of history in the general intellectual culture of our time." For Nevins the problem was essentially one of literary style. If only academic historians wrote with more "grace, color, and verve," they would "create a broader reading public for history." Bender shares Nevins's interest in narrative history, but he recognizes the difficulty of crafting historical narratives, particularly since the "new" history has undermined "the notion of a narrative center" and historians have lost faith in "the idea of progress." "Our task," he writes, is "to conceive of a plot that is adequate to our proliferating knowledge about society." And the complex plot or really plot device that Bender proposes for narrating American history is what he calls "the making of public culture." By including the term "making" in his synthetic concept, Bender (like E. P. Thompson, whose work the phrase invokes) insists on seeing history as an active and contested process. He urges "a national synthesis, but with the 'nation' understood . . . as the ever changing, always contingent outcome of a continuing contest among social groups and ideas for the power to define public culture, thus the nation itself." Bender's contested and contentious notion of public culture offers a promising means of avoiding particularistic and narrow studies without also abandoning the history of women or minorities; reviving traditional narrative forms that ignored conflict, marginal groups, and deviant ideas; or returning to limited definitions of politics and power. Such an approach takes us beyond a working-class history without class relations, a women's history without gender relations, and an Afro-
Peripheral artery disease in patients with diabetes: Epidemiology, mechanisms, and outcomes

Peripheral artery disease (PAD) is the atherosclerosis of lower extremity arteries and is also associated with atherothrombosis of other vascular beds, including the cardiovascular and cerebrovascular systems. The presence of diabetes mellitus greatly increases the risk of PAD, as well as accelerates its course, making these patients more susceptible to ischemic events and impaired functional status compared to patients without diabetes. To minimize these cardiovascular risks it is critical to understand the pathophysiology of atherosclerosis in diabetic patients. This, in turn, can offer insights into the therapeutic avenues available for these patients. This article provides an overview of the epidemiology of PAD in diabetic patients, followed by an analysis of the mechanisms by which altered metabolism in diabetes promotes atherosclerosis and plaque instability. Outcomes of PAD in diabetic patients are also discussed, with a focus on diabetic ulcers and critical limb ischemia.