cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization and Attenuation of Sandwiched Deadband Problem Using Describing Function Analysis and Application to Electrohydraulic Systems Controlled by Closed-Center Valves

Unlike input deadband, the sandwiched deadband between actuator and plant dynamics is very difficult to be explicitly compensated for due to the proceeding actuator dynamics whose effect may not be negligible. The paper presents a practical way to overcome the design conservativeness of existing methods in dealing with sandwiched deadband. Specifically, a describing function based nonlinear analysis method is proposed to characterize the effect of the sandwiched deadband on the stability and performance of the overall closed-loop system. The analysis results can be used to determine the highest closed-loop bandwidth that can be achieved without inducing residual limit cycles and instability. Optimal controller parameters can then be found to maximize the achievable closed-loop control performance. The technique is applied to an electrohydraulic system controlled by closed-center valves and a nonlinear feedback controller. Simulation results showed severe oscillations as the feedback control gains are increased to the predicted threshold values. Comparative experimental results also showed the effectiveness of the proposed method in reducing the conservativeness of traditional design and the improved closed-loop control performance in implementation.
Functions positive-definite on R3 and the Heisenberg group☆

In this paper functions that are simultaneously positive-definite on R3 and the Heisenberg group are considered. The set of cyclic vectors associated to infinite-dimensional representations of the Heisenberg group, realized in L2(R), which give rise to such functions is investigated. It is seen to consist precisely of exponentials of quadratic polynomials for which the leading coefficient has negative real part.
Morphological and Anatomical Characteristics of Blackbrush (Coleogyne ramosissima Torr.) Leaves: A Review of Literature

Abstract Leaves of blackbrush (Coleogyne ramosissima Torr.) shrubs share a number characteristics of leaves of both xerophytic and sclerophyllous shrubs. Despite some leaf surface (morphological) and anatomical similarities with typical xerophytic leaves, blackbrush leaves are more similar to typical semi-arid coastal chaparral plants in Mediterranean and southern California, or cool and high elevation inland desert perennial plants. Semi-deciduous, thick blades, well-cutinized epidermises, numerous small leaves, sclerophyllic leaves, hypostomatry, sunken stomata, thickened epidermal cell walls, and abundant abaxial and adaxial trichomes are characteristics of blackbrush plants, as well as typical woody xerophytic and sclerophyllous plants. Blackbrush also exhibit summer dormancy, with characteristics of revolute margins, uniseriate hypodermis, biseriate epidermis, bifacial palisade parenchyma, and intercellular air space in leaves; all of which are characteristics of leaves from sclerophyllous chaparral ...
Effects of exercise training on left ventricular mass in patients with ischemic heart disease

Abstract To determine whether exercise training results in increased left ventricular mass in patients with ischemic heart disease, we obtained echocardiograms in 14 coronary patients before and after an average of seven months (range 3 to 14 months) of supervised arm and leg exercise. Each echocardiogram was interpreted jointly by two blinded observers, using three different measurement conventions and a semiautomated method of analysis to minimize errors of interpretation. Exercise training led to subjective improvement in all 14 patients, and to an objective increase in functional capacity in 13 of 14 patients, as evidenced by an increase in maximal oxygen consumption estimated from symptom-limited treadmill exercise testing (8.8 ± 2.7 (SD) and 10.7 ± 2.5 METS before and after training, respectively, p
Significance and impact of bisphosphonate-induced acute phase responses

Background: Bisphosphonates are synthetic analogs of inorganic pyrophosphates with high avidity for bone, where they bind to hydroxyapatite crystals. Bisphosphonates are effective in decreasing bone resorption, the incidence of skeletal-related events, and pain from bone metastases. These agents have recently become incorporated into the treatment regimen of patients with osteolytic and osteoblastic metastatic bone disease. Although relatively well tolerated, the initial dose(s) of intravenous aminobisphosphonates can be associated with an acute phase response, a nonspecific physiologic reaction associated with increased levels of inflammatory cytokines, fever, and flu like symptoms including fatigue, nausea, and myalgia.Objective: The purpose of this article is to provide an updated review of the literature in this field.Data Sources: A search of PubMed was performed using the key terms bisphosphonate, acute phase response, and cancer, and limited to publications in English. The published literature on a...
The role of the plasma membrane in the secretion of milk fat

Abstract On the basis of electron microscopic evidence, Bargmann & Knoop (1959) proposed that milk fat is secreted from the lactating cell by progressive envelopment of the fat droplet with plasma membrane at the apex of the cell. Ultimately the fully wrapped globule is pinched off from the cell. Support for this hypothesis is presented here in the form of biochemical data together with a rationale for the biophysics of the process. The biochemical evidence indicates that fat droplets within the cell are relatively devoid of certain membrane constituents, particularly phosphatidyl ethanolamine and carotenoids characteristically present in the surface coat of secreted milk fat globules. From a combination of compositional analyses and turnover studies with 14 C-fatty acid, the logical origin of these components is the plasma membrane of the cell. The envelopment of the droplet appears adequately explained on the basis of London-van der Waals forces which are estimated to achieve an attraction force of one atmosphere when the separating distance between membrane and droplet is reduced to 20 A. Milk proteins appear to be secreted by emptying of vacuoles through the plasma membrane. Membranes around such vacuoles may replenish the plasma membrane used in fat secretion, thus relating the two processes.
The nurture of nature: Social, developmental, and environmental controls of aggression

Evidence from many species suggests that social, developmental, and cognitive variables are important influences on aggression. Few direct activational or organizational effects of hormones on aggression and dominance are found in nonhuman primates. Female aggression and dominance are relatively frequent and occur with low testosterone levels. Social, cultural, and developmental mechanisms have more important influences on dominance and aggression than hormones.
Modification of soy proteins and their adhesive properties on woods

Adhesive properties of trypsin-modified soy proteins (TMSP) on woods were investigated. A simple method developed in our laboratory, consisting of measuring the force required to shear the bond between glued wood pieces in the Instron universal testing machine, was used to examine adhesive strength of modified soy proteins on wood. Adhesive strength of TMSP was measured for cold-pressed (ambient temperature for 2 h) and hot-pressed (60, 80, 100, and 120°C for times varying from 0.5 to 2.5 h) woods. Of the woods examined, soft maple gave the highest strength [743 Newtons (N) at a protein glue concentration of 2 mg/cm2]. For soft maple and cold-pressing, TMSP at 2 mg/cm2 gave twice the adhesive strength of unmodified protein controls, 743 vs. 340 N. Also, the adhesive strength of TMSP increased from 284 to 743 N as glue concentration was increased from 1 to 2 mg/cm2. However, hot-pressing of wood pieces beyond 1 h at 120°C and 30% relative humidity resulted in decreased adhesive strengths of TMSP compared to controls. Further, adhesive strengths of hot-pressed glued wood samples decreased when the relative humidity at which they were kept for curing increased from 30 to 60%. This negative effect of increased humidity on adhesive strengths of glued wood pieces was not observed with cold-pressed TMSP.
The Microbarographic Detection of Nuclear Explosions

In order to study the atmospheric pressure perturbations produced by the passages of gravity and acoustic-gravity waves through the atmosphere, a sensitive rate of change instrument (microbarovariograph) has been developed at Lamont. Similar instruments of different design have also been in successful opertion at several other institutions here and abroad. In general, this instrumentation has also proven capable of recording the pressure variations from nuclear explosions in the megaton range for distances which depend on the magnitude and elevation of the initial explosion. The Lamont pressure transducer is a U-tube manometer using a stable liquid plasticizer, dioctyl sebacate, of very low thermal expansion, vapor pressure and creep. One side of the system is connected to a fixed insulated air reservoir or compliant volume. An adjustable leak in parallel controls the long period time constants. Fluctuations of the liquid level in the open end are sensed by a moving coil in a differential transformer whose 60-cycle output is directly proportional in magnitude to the level changes, provided such changes are small. The signal, amplified and demodulated, gives a sensitivity of about 0.030 millibars (30 dynes per cm2) per cm of scale deflection for a stop displacement. A DC post amplifier can give a sensitivity of about 0.001 millibars (1 dyne per cm2) per cm of scale deflection. At the higher sensitivity, special hydraulic filtering procedures must be employed on the transducer in order to reduce atmospheric noise. Broad band recording is best accomplished at the lower sensitivity.
Proton and carbon‐13 NMR studies of 1‐substituted pyridinium salts

1H and 13C NMR chemical shifts of a series of 1-substituted pyridinium salts were measured in dimethyl sulfoxide. The effect of the quaternary pyridinium ring on the resonance of the methylene group of the substituent is reported. Increments of δ1H = 3.89 ± 0.16 ppm and δ13C = 47.5 ± 3.7 ppm and are estimated for replacing YCH2H with YCH2Py+. The effects of 1-substituents on the pyridinium ring chemical shifts are discussed.
Correlation energy for a slater determinant fitted to the electron density

Recently, a method has been developed which uses experimental crystallographic data to construct orbitals yielding essentially the exact density for the crystals. The wavefunction obtained by this method is a Slater determinant. By using the Colle-Salvetti method we show the correlation energy can be calculated from this Slater determinant. We apply the method to the case of the beryllium atom.
The social ecology of school-age child care

The goal of this longitudinal study was to examine variations in school-age child care arrangements across the elementary school years as a function of child, family, and contextual factors. Pre-kindergarten family background measures were collected through parent questionnaires and interviews. Follow-up interviews with 466 parents provided information on children's care experiences in grades 1 through 5. Some care arrangements (e.g., self care) showed considerable continuity, whereas other arrangements (e.g., school programs) changed substantially from year-to-year. Increases in use were found for self-care, sibling care, neighbor care, and activity-based care; use of day care decreased across years. Children living with working and/or single mothers spent more time in non-parent care, as did boys with behavior problems. Time spent in specific care arrangements varied as a function of child sex, behavioral adjustment, ethnicity, family socio-economic status, mothers' employment, and parents' marital status. These findings underscore the importance of developmental and ecological-contextual factors in families' choices of care arrangements.
The True Incidence of Near-Term Postoperative Complications in Prosthetic Breast Reconstruction Utilizing Human Acellular Dermal Matrices: A Meta-Analysis

Background The use of human acellular dermal matrix (HADM) materials in prosthetic-based breast reconstruction has gained popularity in recent years. Questions remain, however, regarding the nature and incidence of postoperative complications associated with this technique. The results reported in the available literature vary widely. This meta-analysis examines this question further with a broad review of the available literature in an effort to better define the true nature and incidence of near-term complications associated with the use of HADM in prosthetic-based breast reconstruction. It does not aim to compare this method of reconstruction to others.
Structural Determinants of MscL Gating Studied by Molecular Dynamics Simulations

The mechanosensitive channel of large conductance (MscL) in prokaryotes plays a crucial role in exocytosis as well as in the response to osmotic downshock. The channel can be gated by tension in the membrane bilayer. The determination of functionally important residues in MscL, patch-clamp studies of pressure-conductance relationships, and the recently elucidated crystal structure of MscL from Mycobacterium tuberculosis have guided the search for the mechanism of MscL gating. Here, we present a molecular dynamics study of the MscL protein embedded in a fully hydrated POPC bilayer. Simulations totaling 3 ns in length were carried out under conditions of constant temperature and pressure using periodic boundary conditions and full electrostatics. The protein remained in the closed state corresponding to the crystal structure, as evidenced by its impermeability to water. Analysis of equilibrium fluctuations showed that the protein was least mobile in the narrowest part of the channel. The gating process was investigated through simulations of the bare protein under conditions of constant surface tension. Under a range of conditions, the transmembrane helices flattened as the pore widened. Implications for the gating mechanism in light of these and experimental results are discussed.
A RATIONALE FOR STUDIES IN THE CONTROL OF EPIDEMIC INFLUENZA

Influenza has long been a field conducive to fancy and speculation. At present, however, through increasing knowledge of the pathogenesis of the disease and the factors influencing resistance, the collected data are beginning to take form. In this discussion an effort has been made to point out the trends, to interpret their possibilities on the basis of the mechanisms involved, and to give some intimation as to their relative applicabilities and limitations. It is clear that certain of them offer reasonable promise of exerting a real effect in the prevention of influenza; it remains only to prove them.
Smart Portable Rehabilitation Devices

In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device.Copyright © 2005 by ASME
Teaching for creative thinking in the intermediate grades

Creative thinking can be encouraged in the intermediate grades by teaching specific skills that may be integrated into various subject areas.
Is chronically dysfunctional yet viable myocardium distal to a severe coronary stenosis hypoperfused

Abstract Background . Controversy exists regarding the perfusion status of chronically dysfunctional yet viable myocardium. Studies investigating the pathophysiology of this condition have reached different conclusions, with some suggesting that myocardial blood flow (MBF) in these regions is normal at rest with regional dysfunction resulting from repetitive stress-induced ischemia (stunned myocardium), whereas others have proposed that MBF is chronically reduced at rest (hibernating myocardium). However, adequately powered experimental studies investigating this question in an appropriate animal model using clinically available techniques have not been performed. Based on the mixed results of prior studies, we hypothesized that these chronically dysfunctional yet viable regions may actually represent a mixture of hibernation and stunning. Consequently, the purpose of this study was to quantitatively determine the distribution of MBF in left ventricular regions with chronically impaired resting function but preserved viability in a large population of animals with single-vessel coronary stenosis in an attempt to further elucidate the mechanism(s) responsible for chronic, reversible myocardial dysfunction. Methods . Fifty-two adult mini-swine with 90% proximal left circumflex (LCx) stenosis underwent dynamic positron emission tomography (PET) with 13 N-ammonia and 18 F-fluorodeoxyglucose and dobutamine stress echocardiography (DSE) (5 to 40 μg/kg/min) 1 month after stenosis creation. Values of MBF and FDG uptake by PET and wall motion score index (WMSI) by DSE were compared using a standard 16-segment model. Results . Of 312 possible LCx segments seen on PET, 303 (97.1%) were visualized by DSE. Of the 303 LCx segments, 279 (92.1%) had rest dysfunction (WMSI ≥ 2) by DSE. One hundred eighty-two segments (60.1%) had decreased ( 60% reference) FDG uptake and were classified as hibernating. Ninety-two segments (30.4%) had preserved MBF (≥ 85% reference) and were classified as stunned. Five segments (1.7%) with reduced (≤ 60% reference) FDG uptake by PET and akinesis or dyskinesis at rest (WMSI ≥ 3) and no contractile reserve were considered infarcted. Hibernating segments had significantly higher FDG uptake at rest (360.7 ± 48.3 vs 212.3 ± 17.7% septal values; p p p = 0.4), indicating similar degrees of viability. Conclusions . Myocardial hibernation and stunning appear to frequently coexist in regions served by a stenotic coronary vessel. Hibernating regions appear to have greater resting ischemia based on higher values of FDG uptake and greater resting dysfunction. Reversible left ventricular dysfunction in the setting of chronic coronary artery disease is likely due to a combination of these two mechanisms.
Maternal emotional availability at bedtime and infant cortisol at 1 and 3 months.

Abstract Background Previous work has shown that early experience influences infant cortisol secretion. Few studies, however, have examined associations between parenting quality and cortisol levels and patterning in very young infants. Aims This study examined linkages between maternal emotional availability (EA) during a routine caregiving task, bedtime, and infant cortisol in the first 3months of life. Concurrent and longitudinal associations between maternal EA and infant cortisol were examined. Study design Families were visited when their infants were 1 and 3months old. Video equipment was set up in order to record the infant's bedtime routine. Parents were provided with materials with which to take saliva samples from their infants at late afternoon, bedtime, and the following morning. Subjects At 1month, participants were 96 mothers and infants living in a rural U.S. state. Data were available for 88 mothers and infants at 3months. Outcome measures Maternal EA was scored from videotapes of bedtime at each age point. Infant cortisol was assessed from the saliva samples taken by parents. Results Regression analyses indicated that at 1 and 3months of age, infants of more emotionally available mothers showed lower levels of cortisol secretion across the night than infants of less emotionally available mothers. Additionally, multilevel model analyses indicated that infants of more emotionally available mothers showed greater evidence of a decline in their cortisol levels across the evening, followed by an increase across the nighttime into the morning in their cortisol at 3months. Conclusions Findings suggest that maternal care in the context of a routine caregiving task is associated with lower stress reactivity and with earlier circadian patterning in very young infants.
DIVE: A Data Intensive Visualization Engine

Summary: Modern scientific investigation is generating increasingly larger datasets, yet analyzing these data with current tools is challenging. DIVE is a software framework intended to facilitate big data analysis and reduce the time to scientific insight. Here, we present features of the framework and demonstrate DIVE’s application to the Dynameomics project, looking specifically at two proteins. Availability and implementation: Binaries and documentation are available at http://www.dynameomics.org/DIVE/DIVESetup.exe. Contact: daggett@uw.edu Supplementary information: Supplementary data are available at Bioinformatics online.
The role of the fallopian tube in the origin of ovarian cancer

Advanced cases of epithelial ovarian, primary peritoneal, and primary tubal malignancies have a relatively poor prognosis and collectively remain the most deadly of all gynecologic malignancies. Although traditionally thought of as one disease process, ongoing research suggests that there is not 1 single site or cell type from which these cancers arise. A majority of the serous tumors appear to originate from dysplastic lesions in the distal fallopian tube. Therefore, what we have traditionally considered “ovarian” cancer may in fact be tubal in origin. In this article, we will review epithelial ovarian cancer classification and genetics, theories regarding cells of origin with a focus on tubal intraepithelial carcinoma, and implications for prevention and screening.
The Origins of Thomas Jefferson's Anti-Clericalism

Cannibals - mountebanks - charlatans - pious and whining hypocrites - necromancers - pseudo-Christians - mystery mongers. These are among the epithets which Thomas Jefferson applied to the clergy of the Protestant denominations and of the Roman Catholic Church as well. It was they who “perverted” the principles of Jesus “into an engine for enslaving mankind”; it was the Christian “priesthood” who had turned organized religion into a “mere contrivance to filch wealth and power” for themselves; they were the ones who throughout history had persecuted rational men for refusing to swallow “their impious heresies.”
North-South trade and standards: what can general equilibrium analysis tell us?

The tension between standards being a response to market failures versus creating barriers to trade characterizes much of their economic analysis. This article explores in more detail the link between international trade and standards based on resolution of a public bad(s) problem. Specifically, a general equilibrium setting is sketched out, drawing on existing analysis in the trade and environmental economics literature, and designed to capture some key stylized facts and basic hypotheses concerning North-South trade where standards are targeted at negative externalities in production. The key conclusions to be drawn are that while a clear theoretical foundation exists for the hypothesis of 'standards as barriers' to trade, and the likely benefits of aid for trade programs, this is not the case for the hypothesis of 'barriers as a catalyst' for trade, pointing to the need for further research on the latter hypothesis.
A Theory of Role Composition

We study the access control integration problem for web services. Organizations frequently use many services, each with its own access control policies, which must interoperate while maintaining secure access to information. The integration problem is to take the set of such services and to find a globally consistent access control policy that ensures that the system composed from the services does not have any authorization failures or information disclosures. We give a sound and complete algorithm for access control integration by reducing the problem to Boolean constraint solving. We have implemented ROLEMATCHER, a tool to infer global role-based access control schemas for a set of services, and show on examples that it can quickly infer global roles for composed systems, or determine the absence of a globally consistent role schema.
EFFICIENT GLOBAL COMBINE OPERATIONS IN MULTI-PORT MESSAGE-PASSING SYSTEMS

We present a class of efficient algorithms for global combine operations in k-port message-passing systems. In the k-port communication model, in each communication round, a processor can send data...
Subchronic Toxicity and Developmental Toxicity Studies in Rats With Aquateric® Aqueous Enteric Coating

Studies were conducted to evaluate the subchronic and developmental toxicity of Aquateric® Aqueous Enteric Coating. Homogeneity and stability studies were conducted over a range of 5,000 to 50,000 ppm Aquateric in the diet. In the subchronic study, groups of Sprague-Dawley rats (20/sex/group) received 0 (control), 5,000, 25,000, or 50,000 ppm Aquateric in the diet for 90 consecutive days. No mortality, clinical signs of toxicity or adverse toxicological effects on hematology or serum chemistry parameters, body weights, feed consumption, ophthalmological examinations, or histological evaluation of tissues were noted in any treatment group. In the developmental toxicity study, groups of pregnant Sprague-Dawley rats (25/group) received 0 (control), 5,000, 25,000 or 50,000 ppm Aquateric in the diet on gestational days 6-15. No evidence of maternal toxicity or fetotoxicity or embryotoxicity was noted. The no observed adverse effect level (NOAEL) exceeds 50,000 ppm in the diet, which represents a dose range of approximately 3600 to 4100 mg/kg/day. The results of these studies demonstrate the low toxicity of Aquateric. The estimated human intake is approximately 4 mg/kg/day. Based on the NOAEL from the subchronic study of 3604 mg/kg/day, the margin of safety is 900.
Group V sPLA2 Hydrolysis of Low-Density Lipoprotein Results in Spontaneous Particle Aggregation and Promotes Macrophage Foam Cell Formation

Objectives— Secretory phospholipase A 2 (sPLA 2 ) enzymes hydrolyze the sn-2 fatty acyl ester bond of phospholipids to produce a free fatty acid and a lysophospholid. Group V sPLA 2 is expressed in cultured macrophage cells and has high affinity for phosphatidyl choline-containing substrates. The present study assesses the presence of group V sPLA 2 in human and mouse atherosclerotic lesions and its activity toward low-density lipoprotein (LDL) particles. Methods and Results— Group V sPLA 2 was detected in human and mouse atherosclerotic lesions by immunohistochemical staining. Electron microscopic analysis showed that mouse group V sPLA 2 -modified LDL is significantly smaller (mean diameter±SEM=25.3±0.25 nm) than native LDL (mean diameter±SEM=27.7±0.29 nm). Hydrolysis by group V sPLA 2 induced spontaneous particle aggregation; the extent of aggregation was directly proportional to the degree of LDL hydrolysis. Group V sPLA 2 modification of LDL led to enhanced lipid accumulation in cultured mouse peritoneal macrophage cells. Conclusions— Group V sPLA 2 may play an important role in promoting atherosclerotic lesion development by modifying LDL particles in the arterial wall, thereby enhancing particle aggregation, retention, and macrophage uptake.
Environmental Contaminant Exposures and Preterm Birth: A Comprehensive Review

Preterm birth is a significant public health concern, as it is associated with high risk of infant mortality, various morbidities in both the neonatal period and later in life, and a significant societal economic burden. As many cases are of unknown etiology, identification of the contribution of environmental contaminant exposures is a priority in the study of preterm birth. This is a comprehensive review of all known studies published from 1992 through August 2012 linking maternal exposure to environmental chemicals during pregnancy with preterm birth. Using PubMed searches, studies were identified that examined associations between preterm birth and exposure to five categories of environmental toxicants, including persistent organic pollutants, drinking-water contaminants, atmospheric pollutants, metals and metalloids, and other environmental contaminants. Individual studies were summarized and specific suggestions were made for future work in regard to exposure and outcome assessment methods as well as study design, with the recommendation of focusing on potential mediating toxicological mechanisms. In conclusion, no consistent evidence was found for positive associations between individual chemical exposures and preterm birth. By identifying limitations and addressing the gaps that may have impeded the ability to identify true associations thus far, this review can guide future epidemiologic studies of environmental exposures and preterm birth.
Decision accuracy in complex environments is often maximized by small group sizes

Individuals in groups, whether composed of humans or other animal species, often make important decisions collectively, including avoiding predators, selecting a direction in which to migrate and electing political leaders. Theoretical and empirical work suggests that collective decisions can be more accurate than individual decisions, a phenomenon known as the ‘wisdom of crowds’. In these previous studies, it has been assumed that individuals make independent estimates based on a single environmental cue. In the real world, however, most cues exhibit some spatial and temporal correlation, and consequently, the sensory information that near neighbours detect will also be, to some degree, correlated. Furthermore, it may be rare for an environment to contain only a single informative cue, with multiple cues being the norm. We demonstrate, using two simple models, that taking this natural complexity into account considerably alters the relationship between group size and decision-making accuracy. In only a minority of environments do we observe the typical wisdom of crowds phenomenon (whereby collective accuracy increases monotonically with group size). When the wisdom of crowds is not observed, we find that a finite, and often small, group size maximizes decision accuracy. We reveal that, counterintuitively, it is the noise inherent in these small groups that enhances their accuracy, allowing individuals in such groups to avoid the detrimental effects of correlated information while exploiting the benefits of collective decision-making. Our results demonstrate that the conventional view of the wisdom of crowds may not be informative in complex and realistic environments, and that being in small groups can maximize decision accuracy across many contexts.
Allograft Rejection - Fact and Fancy

Only within the past few decades have immunobiologists begun to appreciate the full complexities of allograft rejection, that dramatic multifaceted and powerful cascade of host responses that are called into play by and lead to the destruction of genetically dissimilar tissues and organs. The modern era of transplantation biology opened during World War II when Medawar initiated studies of the behavior of skin allografts, first on burned airmen then on rabbits, nothing that the progressive infiltration of the graft by lymphocytes and macrophages presaged graft destruction (Medawar, 1956–1957). He also showed that the destruction of a second set of skin grafts was accelerated after transplantation to animals, which had previously rejected skin from the same donor, concluding that the host had become sensitized selectively against the antigen. About the same time, the development of inbred murine strains provided opportunities to perform reproducible and well-controlled investigations into this burgeoning biology. Mitchinson (1954) and Billingham et al. (1954) used such strains to demonstrate that the immunity of animals sensitized to a tumor or skin graft could be conferred by transfer of lymphoid cells to syngeneic hosts. Using inbred rats, Gowans et al. (1962) then showed that small lymphocytes recirculated and were the prototypic immunologically competent cells.
Supervised Learning of Quantizer Codebooks by Information Loss Minimization

This paper proposes a technique for jointly quantizing continuous features and the posterior distributions of their class labels based on minimizing empirical information loss such that the quantizer index of a given feature vector approximates a sufficient statistic for its class label. Informally, the quantized representation retains as much information as possible for classifying the feature vector correctly. We derive an alternating minimization procedure for simultaneously learning codebooks in the Euclidean feature space and in the simplex of posterior class distributions. The resulting quantizer can be used to encode unlabeled points outside the training set and to predict their posterior class distributions, and has an elegant interpretation in terms of lossless source coding. The proposed method is validated on synthetic and real data sets and is applied to two diverse problems: learning discriminative visual vocabularies for bag-of-features image classification and image segmentation.
Performance analysis of multi-hop wireless ad hoc networks using IEEE 802.11 DCF

A novel methodology is presented for the investigation of performance and optimization strategies for multi-hop wireless ad hoc networks. The powerful analytical approach is based on two newly defined abstractions: the "deferral set" and the "equivalent competitor" which provide the basis for efficient and elegant models for competitive access and routing in ad hoc networks. Fundamental capacity analysis is facilitated by applying these concepts to detailed models of node behavior. This paper presents theoretical analysis of mean channel throughput and service times during back-logged periods. The results are validated via discrete event simulation (DES).
Real-Time Implementation of an Optimal Transient Neurocontroller for a GCSC

This paper presents the design of an optimal auxiliary transient neurocontroller (ATNC) for the gate controlled series capacitor (GCSC) in a multi-machine power system. GCSC is a recent advancement in the family of series FACTS devices. While GCSC regulates power flow through a transmission line, an auxiliary control signal can provide damping to the power oscillations during disturbances. The ATNC has been designed using heuristic dynamic programming to develop an optimal neurocontroller with fixed weights. The ATNC is implemented in real-time using the TMS3206701 DSP and the real-time digital simulator (RTDS). Results are presented to show the effectiveness of the ATNC in damping transient oscillations during disturbances.
Sophorolipids, Microbial Glycolipids with Anti-Human Immunodeficiency Virus and Sperm-Immobilizing Activities

The increased incidence of human immunodeficiency virus (HIV)/AIDS disease in women aged 15 to 49 years has identified the urgent need for a female-controlled, efficacious, and safe vaginal topical microbicide. To meet this challenge, sophorolipid (SL) produced by Candida bombicola and its structural analogs have been studied in this report for their spermicidal, anti-HIV, and cytotoxic activities. The sophorolipid diacetate ethyl ester derivative is the most potent spermicidal and virucidal agent of the series of SLs studied. Its virucidal activity against HIV and sperm-immobilizing activity against human semen are similar to those of nonoxynol-9. However, it also induced enough vaginal cell toxicity to raise concerns about its applicability for long-term microbicidal contraception. Its structure-activity relationship has been established for creating new analogs with less cytotoxicity and higher activity.
High telomerase is a hallmark of undifferentiated spermatogonia and is required for maintenance of male germline stem cells

Telomerase inactivation causes loss of the male germline in worms, fish, and mice, indicating a conserved dependence on telomere maintenance in this cell lineage. Here, using telomerase reverse transcriptase (Tert) reporter mice, we found that very high telomerase expression is a hallmark of undifferentiated spermatogonia, the mitotic population where germline stem cells reside. We exploited these high telomerase levels as a basis for purifying undifferentiated spermatogonia using fluorescence-activated cell sorting. Telomerase levels in undifferentiated spermatogonia and embryonic stem cells are comparable and much greater than in somatic progenitor compartments. Within the germline, we uncovered an unanticipated gradient of telomerase activity that also enables isolation of more mature populations. Transcriptomic comparisons of Tert(High) undifferentiated spermatogonia and Tert(Low) differentiated spermatogonia by RNA sequencing reveals marked differences in cell cycle and key molecular features of each compartment. Transplantation studies show that germline stem cell activity is confined to the Tert(High) cKit(-) population. Telomere shortening in telomerase knockout strains causes depletion of undifferentiated spermatogonia and eventual loss of all germ cells after undifferentiated spermatogonia drop below a critical threshold. These data reveal that high telomerase expression is a fundamental characteristic of germline stem cells, thus explaining the broad dependence on telomerase for germline immortality in metazoans.
Phylogeny, Behavior, and Ecology in the Mammalia

In a review written some 11 and published 9 years ago, I attempted to summarize the literature concerning mammalian social behavior and then proceeded to discuss two major issues: (1) the relationship of social structure to the species’ habitat and economy, and (2) the influence of evolutionary history on the form of social organization displayed (Eisenberg, 1966). The almost exponential increase of information during the last decade concerning mammalian social behavior and ecology, as well as the founding of social ecology as a subdiscipline (Crook, 1970), have rendered my earlier review out of date. My co-workers and I have recently attempted two reviews, one for primates, the other for selected carnivores (Eisenberg et al., 1972; Kleiman and Eisenberg, 1973). The problems of correlation and reconstruction remain as challenging as ever.
New Perspectives for Science Transfer

There is no question that we live and work in a global community. While some parts of our globe remain remote for many of us, we nonetheless can and will be affected by what occurs throughout the world. This is true in business and social aspects of life, and it is especially true with respect to
A Tax Lawyer's Perspective on Section 527 Organizations

Proponents of campaign finance reform generally assume that, by definition, all section 527 organizations are partisan, election-driven organizations. They also believe that by self-identifying to the IRS, these organizations receive substantial tax benefits. Based on these presuppositions, reformers argue that strict regulation of 527 organizations is both constitutional and normatively beneficial. In this Essay, I argue that once section 527 is carefully analyzed from a tax perspective, it becomes evident that these assumptions are flawed. Ultimately, I conclude that section 527 should not be used as a mechanism for regulating campaign finance.
Length-dependent thermal conductivity of single extended polymer chains

The low thermal conductivity of polymers will be one of the major roadblocks for the polymer-based microelectronics and macroelectronics due to the limited heat spreading capability. Despite that the thermal conductivity of bulk polymers is usually low, a single extended polymer chain could have very high thermal conductivity. In this paper we present atomistic simulation studies on the phonon transport in single extended polymer chains of various polymers as a function of polymer chain length. The thermal conductivity of single extended polymer chains can be 1--2 orders of magnitude higher than their bulk counterparts. The thermal conductivity of single extended polymer chains is a strong function of monomer type. For example, the thermal conductivity of the extended polymer chains with aromatic backbone can be up to 5 times as that of a polyethylene chain, while the thermal conductivity of the extended polymer chains with bond-strength or mass disorder can be only 1/25 as that of a polyethylene chain. We analyze the phonon transport mechanisms in single extended polymer chains of various polymers and find that the competition between ballistic phonon transport and diffusive phonon transport in a polymer chain leads to a diverging length-dependent thermal conductivity.
Infectious complication of Blunt head injury

A middle-aged man presented to a rural hospital in South Africa with a history of head trauma. He reported being attacked and stoned 2 weeks prior, and subsequently noticed drainage from a wound he sustained during the assault. On physical exam, he had a 3 cm×2 cm forehead wound with purulent drainage. Neurologic exam showed no focal deficits. Lateral and frontal skull films …
Vision-Based Roll and Pitch Estimation in Precision Projectiles

Vision-based roll and pitch attitude and rate estimation algorithms were developed for gun-launched precision projectiles. The gun-launched environment features unique challenges to interpreting data from a strapped-down imager on a projectile experiencing roll rates in the range of tens or even hundreds of revolutions per second. The goal of the present work is to develop vision-based algorithms for estimating the attitude of projectiles. The roll and pitch attitudes are determined using two horizon detection methods, the Hough transform and intensity standard deviation. The Hough transform method determined roll angle to better than 0.1° error variance in experiments when a forward-looking imager was spun. The intensity standard deviation algorithm estimated attitude to an average of 1° and 3° and standard deviation of 4° pitch and 6° roll in experiments with a side-facing imager.
Computation of Rotor Noise Generation in Grid Turbulence Using Large-Eddy Simulation

Large-eddy simulation of turbulent flow interaction with a ten-bladed rotor is performed to investigate the turbulence ingestion noise. The turbulent inflow is homogeneous and isotropic, mimicking grid-generated turbulence in a previous experiment. The acoustic response of the rotor is computed at low Mach numbers using the Ffowcs Williams-Hawkings extension to the Lighthill theory. Results show that turbulence ingestion noise is broadband with small spectral peaks at the blade passing frequency and its harmonics. It is much stronger than the rotor self noise generated by vortex shedding. The computed sound pressure spectrum exhibits a similar shape to the experimental spectrum but the level is lower by 2–5 dB, which is likely due to a mismatch in the incident flow condition and is under further investigation. The effects of different levels of acoustic compactness assumptions on the sound prediction are evaluated and discussed.
The Golgi apparatus: insights from lipid biochemistry

Discovered by Camillo Golgi in 1898 [ l , 21, the Golgi apparatus has long fascinated cytologists because of its distinct morphology (Fig. 1). This organelle, which is found in all eukaryotic cells, consists of flat cisternae arranged in parallel to form the characteristic ‘stacks’ that are interconnected by cisternal or tubular-reticular bridges. In addition, numerous small membranous vesicles are usually found associated with the organelle. The Golgi apparatus is currently the focus of much attention among cell and membrane biologists because of its central role in directing protein traffic within cells. At least three areas, the cis, medial, and trans subsections can be seen by electron microscopy. The cis compartments are often situated closest to the nucleus, while the trans elements are most distant. From biochemical studies we know that there are at least three functionally distinct compartments that operate sequentially to build the oligosaccharide chains on transported glycoproteins and to ‘sort’ proteins destined for transport to other regions of the cell (e.g. the lysosomes, cell surface or secretory granules). Excellent reviews on various
The Relationship between Emotion Regulation, Social Support, and Alcohol-Related Problems among Racially Diverse Adolescents.

AbstractPurpose: This study examined associations among alcohol-related problems and family support, collective efficacy, emotion-regulation drinking motives, and limited access to emotion-regulation strategies among racially diverse adolescents. Methods: The sample included 150 racially diverse adolescent girls and boys (53.3% male) from two urban high schools in different geographic regions. Results: Family support and collective efficacy were negatively correlated, and emotion-regulation drinking motives and limited access to emotion-regulation strategies positively correlated, with alcohol-related problems. Accounting for geographic location and drinking level, emotion-regulation drinking motives and limited access to emotion-regulation strategies uniquely predicted the number of different alcohol-related problems. Conclusions: Results suggest the importance of including social and emotion factors in examinations of adolescent alcohol-related problems.
Strain analysis of nanowire interfaces in multiscale composites

Recently, the reinforcement-matrix interface of fiber reinforced polymers has been modified through grafting nanostructures – particularly carbon nanotubes and ZnO nanowires – on to the fiber surface. This type of interface engineering has made a great impact on the development of multiscale composites that have high stiffness, interfacial strength, toughness, and vibrational damping – qualities that are mutually exclusive to a degree in most raw materials. Although the efficacy of such nanostructured interfaces has been established, the reinforcement mechanisms of these multiscale composites have not been explored. Here, strain transfer across a nanowire interphase is studied in order to gain a heightened understanding of the working principles of physical interface modification and the formation of a functional gradient. This problem is studied using a functionally graded piezoelectric interface composed of vertically aligned lead zirconate titanate nanowires, as their piezoelectric properties can be utilized to precisely control the strain on one side of the interface. The displacement and strain across the nanowire interface is captured using digital image correlation. It is demonstrated that the material gradient created through nanowires cause a smooth strain transfer from reinforcement phase into matrix phase that eliminates the stress concentration between these phases, which have highly mismatched elasticity.