cssi/SciSciGPT-SciSciNet huggingface dataset:
Woodland resilience to regional drought: Dominant controls on tree regeneration following overstorey mortality

Drought events occurring under warmer temperatures (i.e. “hotter droughts”) have resulted in widespread tree mortality across the globe, and may result in biome-level vegetation shifts to alternate vegetation types if there is a failure of trees to regenerate. We investigated how overstorey trees, understorey vegetation, and local climatic and edaphic conditions interact to influence tree regeneration, a key prerequisite for resilience, in a region that has experienced severe overstorey tree mortality due to hotter droughts and beetle infestations. We used detailed field observations from 142 sites that spanned a broad range of environmental conditions to evaluate the effects of climate and recent tree mortality on tree regeneration dynamics in the spatially extensive pinon (Pinus edulis)-juniper (Juniperus osteosperma, Juniperus monosperma) woodland vegetation type of the southwestern USA. We used a structural equation modelling framework to identify how tree mortality and local climatic and edaphic conditions affect pinon and juniper regeneration and electivity analyses to quantify the species-specific associations of tree juveniles with overstorey trees and understorey shrubs. Pinon regeneration appears to be strongly dependent upon advanced regeneration, (i.e. the survival of juvenile trees that established prior to the mortality event), the survival of adult seed-bearing trees (inferred from basal area of surviving trees) and the facilitative effects of overstorey trees for providing favourable microsites for seedling establishment. Model results suggest that local edaphoclimatic conditions directly affected pinon and juniper regeneration, such that stands with hotter, drier local climatic conditions and lower soil available water capacity had limited tree regeneration following large-scale dieback. Synthesis. We identify four indicators of resilience to hotter drought conditions: (1) abundant advance regeneration of tree seedlings; (2) sufficient canopy cover for survival of emergent seedlings and existing regeneration; (3) sufficient seed source from surviving trees with high reproductive output; (4) areas with cooler and wetter local climates and greater soil available water capacity. In the absence of these conditions, there is greater likelihood of woodlands transitioning to more xeric vegetation types following dieback.
Emerging therapies for atopic dermatitis: JAK inhibitors.

The Janus kinase–signal transducer and activator of transcription pathway is a conserved master regulator of immunity and myeloproliferation. Advanced understanding of this pathway has led to development of targeted inhibitors of Janus kinases (Jakinibs). As a class, JAK inhibitors effectively treat a multitude of hematologic and inflammatory diseases. Given such success, use of JAK inhibitors for mitigation of atopic dermatitis is under active investigation. Herein, we review the evolving data on the safety and efficacy of JAK inhibitors in treatment of atopic dermatitis. Although it is still early in the study of JAK inhibitors for atopic dermatitis, evidence identifies JAK inhibitors as effective alternatives to conventional therapies. Nonetheless, multiple large safety and efficacy trials are needed before widespread use of JAK inhibitors can be advocated for atopic dermatitis.
Invited talk: Developing deep multi-source intelligent learning that facilitates the advancement of single cell genomics research

Thanks to recent advances in the field of genomics, it is now possible to create a comprehensive atlas of the basic units of life—cells. In this paper, we present a frame work for single cell genomics research which employs several new machine learning models such as convolutional neural networks, deep auto-encoder, recurrent neural networks etc. With these effective learning models on multi-source data, such as biomedical literatures and cell images, we can achieve novel cell types and functional gene sets.
Improving clinical outcomes for women with overactive bladder or urinary retention symptoms: a comparison of motor response voltages (1-9 V) during Stage 1 sacral neuromodulation

OBJECTIVE To assess whether the utilisation of a motor response of 4 V in patients with overactive bladder (OAB) or urinary retention symptoms. PATIENTS AND METHODS An observational, retrospective, double cohort review was conducted of 339 female patients who had experienced medically recalcitrant OAB or urinary retention symptoms. Between September 2001 and September 2014, both cohorts underwent successful Stage 1 to Stage 2 SNM placement. Group A, included 174 women with a motor response at ≤3 V; and Group B, evaluated 110 women with a motor response at ≥4 V for medically recalcitrant OAB. Group C, compared 33 women with a motor response at ≤3 V; and Group D, documented 22 women with a motor response at ≥4 V for non-obstructive urinary retention. Patients completed 3-day voiding diaries, the Urogenital Distress Inventory-6 (UDI-6), Incontinence Impact Questionnaire-7 (IIQ-7), and Patient Global Impression of Improvement Questionnaire. RESULTS The mean (sd) follow-up was 116.3 (30.3) months in Group A and 112 (34.6) months in Group B (P < 0.354); 150.5 (20.4) months in Group C and 145.8 (17.2) months in Group D (P < 0.38). Successful conversion of Stage 1 to Stage 2 showed statistically significant improvement for both <3-V groups (Groups A and C). Group A had a 93.5% (174/186) conversion rate vs 72.3% (110/152) in Group B for OAB symptoms (P < 0.001). Group C had a 94% (34/36) conversion rate vs 70% (21/30) in Group D (P < 0.017). Defined as a ≥50% reduction in frequency, urgency, urgency incontinence and nocturia, and UDI-6 and IIQ-7 scores, the success rate for Group A was 82.1% (143/174) and for Group B was 63% (69/110) (P < 0.001). The mean battery life improved in both <3-V cohorts (P < 0.001). Annual reprogramming sessions were reduced in Group A and Group C (P < 0.001). Subset analysis of variance showed no statistical improvement in most patient outcomes when 1-V subjects were compared to 2- and 3-V cohorts. However, 32% of 1-V patients (P < 0.001) noted the onset of severe pelvic/perirectal pain and big toe plantar flexion movement with small increments in voltage (0.1-0.2 V) during reprogramming. Only 7% of 2-V and 1% of 3-V patients experienced this complication. CONCLUSIONS Significant improvement was noted (up to 40%) in most clinical voiding parameters in the <3-V patients for both OAB and urinary retention. While <3 V will still statistically improve patient outcomes, a voltage <2 V may elicit self-reprogramming pain with severe bellows and plantar flexion movement, which may discourage patients from therapy adjustments. We recommend randomised, controlled trials to confirm these results.
Ascessi intra-addominali

I contenuti di questo capitolo potrebbero essere sintetizzati in un’unica frase: un ascesso e una struttura limitata contenente del pus che richiede di essere drenata con qualsiasi mezzo a disposizione. Tuttavia riteniamo che preferiate vi siano forniti altri particolari.
Interpreting t-statistics under publication bias: rough rules of thumb

A key issue is how to interpret t-statistics when publication bias is present. In this paper we propose a set of rough rules of thumb to assist readers to interpret t-values in published results under publication bias. Unlike most previous methods that utilize collections of studies, our approach evaluates the strength of evidence under publication bias when there is only a single study. We first re-interpret t-statistics in a one-tailed hypothesis test in terms of their associated p-values when there is extreme publication bias, that is, when no null findings are published. We then consider the consequences of different degrees of publication bias. We show that under even moderate levels of publication bias adjusting one’s p-values to insure Type I error rates of either 0.05 or 0.01 result in far higher t-values than those in a conventional t-statistics table. Under a conservative assumption that publication bias occurs 20 percent of the time, with a one-tailed test at a significance level of 0.05, a t-value equal or greater than 2.311 is needed. For a two-tailed test the appropriate standard would be equal or above 2.766. Both cutoffs are far higher than the traditional ones of 1.645 and 1.96. To achieve a p-value less than 0.01, the adjusted t-values would be 2.865 (one-tail) and 3.254 (two-tail), as opposed to the traditional values 2.326 (one-tail) and 2.576 (two-tail). We illustrate our approach by applying it to evaluate the hypothesis tests in recent issues of Criminology and Journal of Quantitative Criminology (JQC). Under publication bias much higher t-values are needed to restore the intended p-value. By comparing the observed test scores with the adjusted critical values, this paper provides a rough rule of thumb for readers to evaluate the degree to which a reported positive result in a single publication reflects a true positive effect. Further measures to increase the reporting of robust null findings are needed to ameliorate the issue of publication bias.
The mechanistic duality of (thio)urea organocatalysts for ring-opening polymerization

Among the various catalysts for ROP, H-bonding organocatalysts stand out in the precise level of reaction control they are able to render during ROP. The H-bonding class of organocatalysts are thought to effect ROP via dual activation of both monomer and chain end. (Thio)urea mediated ROP has experienced a renaissance as a new polymerization mechanism - mediated by imidate or thioimidate species - facilitates new modes of reactivity and new synthetic abilities. Indeed, the urea class of H-bond donors has been shown to be more active than their corresponding thioureas. The imidate mechanism remains highly active in polar solvents and exhibits remarkable control - and 'living' behavior - under solvent-free conditions, and a broad range of temperatures is accessible. The advancements in synthetic abilities have all evolved through a greater understanding of reaction mechanism. Through the continued synergistic advances of catalysis and material, the (thio)urea class of catalyst can find use in a host of potential applications, research and industrial environments.
Mass Driven Fluctuations Within the Ekman Boundary Layer

Summary A theoretical model to describe the fluctuations within the surface Ekman boundary layer below the Arctic ice cover has been formulated with the novel feature being a source of mass at the ice boundary. The full physics of this problem is developed together with numerical integration of the governing equations that are used in order to explore salient correlations and the structure of the surface layer. The surface layer per se is considered well mixed and bounded below by a strong pycnocline. Using linear theory, it is shown that forced unsteady motions can be significant for modest values of the mass flux and present different characteristics than would have been possible if the boundary had been simply passive. The conclusion is that the complete perturbation field in such a region (and indeed analogous layers where active boundary conditions can be invoked) must be due to a combination that is made up of both the forced and the more conventional self-excited oscillations.
Hybrid entrepreneurs’ self-efficacy and persistence change: A longitudinal exploration

Abstract Hybrid entrepreneurship—where an individual simultaneously engages in startup activities as well as wage-based employment—is an increasingly common career transition path. Yet, relatively little research has explored entrepreneurial characteristics during these unique career transitions. We provide exploratory insight into the longitudinal relationship between self-efficacy and persistence for hybrid entrepreneurs’ (N = 29) across a twenty-week period during which aspiring entrepreneurs engaged in activities related to venture startup while maintaining wage employment. As such, we propose that entrepreneurial self-efficacy (ESE) and entrepreneurial persistence are malleable concepts that change over time. Using our longitudinal sample, we find evidence that ESE predicts entrepreneurial persistence change over time. Perhaps more importantly, we model how changes in ESE over time affect changes in entrepreneurial persistence for hybrid entrepreneurs. In sum, our work provides a foundation from which future research can examine the longitudinal transition of nascent entrepreneurs moving from an occupational setting as an employee to launching their own venture.
Gastric emptying of "clear liquid drinks" assessed with gastric ultrasonography: a blinded, randomized pilot study.

Background Protein-containing liquids may delay gastric emptying and increase risk of aspiration. Commercial whey protein nutritional drinks (WPNDs) are advertised as "clear liquid nutritional drinks" and can be mistaken for protein-free, carbohydrate-based clear liquids. We used gastric ultrasonography to compare gastric emptying of a protein-free, carbohydrate-based clear liquid with that of a WPND in healthy volunteers. Methods We recruited 19 adult (age ≥18 years) volunteers with a body mass index less than 40 kg/m2 and without a history of diabetes mellitus, dysphagia, prior gastric surgery, or allergy to the ingredients of apple juice (AJ) or a WPND. After fasting for eight hours, the volunteers randomly received 474 mL of AJ or a WPND. Gastric ultrasonographic measurements were obtained at baseline and at 0, 30, 60, and 120 minutes after ingestion of the liquid. Results We enrolled 19 volunteers. At 120 minutes after consumption, volunteers who ingested a WPND had a larger estimated gastric volume (GV) than volunteers who ingested AJ (median [interquartile range], 101.3 [70.0-137.4] vs. 50.6 [43.9-81.8] mL; P=.08). By using the 2-sample t test and an α level of .05, we determined that the study had 40% power to detect a significant difference in GV. Future studies need to include 24 participants per group to detect a significant difference. Conclusions Although consumption of a WPND was associated with a larger estimated GV in this pilot study, a larger study is necessary to conclude whether patients must fast longer than two hours after consumption of a WPND.
How China Sees the World: Han‐Centrism and the Balance of Power in International Politics. By John M. Friend and Bradley A. Thayer. (Lincoln, NE: University of Nebraska Press, 2018. Pp. xii, 179. $27.95.)

This short book deals with a hard‐to‐measure force in Chinese foreign relations. Han‐Centrism is seen as a virulent form of Chinese nationalism which asserts that Han Chinese are superior to other ...
Using signed language collocations to investigate acquisition: A commentary on Ambridge (2020):

The visual-manual modality of sign languages renders them a unique test case for language acquisition and processing theories. In this commentary the authors describe evidence from signed languages...
Incoherent Definite Spaces and Shimura Varieties

In this paper, we define incoherent definite quadratic spaces over totally real number fields and incoherent definite Hermitian spaces over CM fields. We use the neighbors of these spaces to study the local points of orthogonal and unitary Shimura varieties.
The automated design of local optimizers for memetic algorithms employing supportive coevolution

One promising method of improving Evolutionary Algorithm (EA) performance is to improve its fine tuning capabilities by using an additional local optimization operator in the evolutionary cycle. This customization on the traditional EA is typically called a Memetic Algorithm (MA). Adding the appropriate local optimization algorithm can increase performance, while a poor choice can decrease performance. Thus, some knowledge is required to select the correct algorithm. In many cases the optimal algorithm selection is not known and it may not be static, but could change during evolution. This investigation combines a method of local optimizer evolution using Push Genetic Programming with a method of automatic, self-configuration called Supportive Coevolution. This combination creates a novel MA that coevolves local optimization operators with target fitness function solution candidates. Implementation methodology is shown and experimentation details with corresponding results are presented. Some additional parameters that were discovered for performance tuning are discussed along with a study of their impact on the algorithm's performance. Discussion of some interesting insights followed by some suggestions for further investigation are also provided. Results show the proposed technique can improve the performance of an EA by providing automatically configured, coevolved local optimization operators to a MA.
Teacher Experience, Personal Health, and Dieting Status Is Associated With Classroom Health-Related Practices and Modeling.

BACKGROUND Evidence suggests that schools play an important role in student health; however, little is known about variability in teachers' use of food-related classroom practices. In this study, we examined associations between teacher demographic and individual factors and their food-related practices and modeling in the classroom. METHODS We had 239 teachers in the United States complete an online survey about their demographics (years of teaching experience, socioeconomic status of the school), personal health status, height and weight, and nutrition knowledge. Teachers also reported on the unhealthy food-related practices they use in their classroom (eg, candy as a reward) and modeling (ie, engaging in unhealthy and healthy eating practices in front of students). RESULTS Hierarchical linear regressions were computed for each outcome separately. After controlling for socioeconomic status, fewer years of teaching experience and lower perception of personal health were associated with the use of unhealthy practices in the classroom. Teachers who were dieting were more likely to endorse healthy modeling. CONCLUSIONS Teacher demographic and individual factors are associated with food-related classroom behavior. These findings have implications for interventions to promote the health of teachers and their students.
Neutrophil-to-Lymphocyte Ratio Predicts High-Risk Explant Features and Waitlist Survival But Is Not Independently Associated With Recurrence or Survival Following Liver Transplantation for Hepatocellular Carcinoma.

We assessed the prognostic significance and the clinical stability of the neutrophil-to-lymphocyte ratio (NLR) before liver transplantation (LT) in a large cohort of patients with hepatocellular carcinoma (HCC) from a region with a long waitlist time. A high preoperative NLR ≥5 has been reported to predict poor outcomes following LT for HCC, and the NLR has been incorporated into several prognostic models. We evaluated 758 patients with HCC with Model for End-Stage Liver Disease exceptions and listed for LT from 2002 to 2015 at a single LT center, of which 505 underwent LT and 253 dropped out before LT. The NLR was collected in all patients at LT and, if available, between 15 and 90 days before LT (NLR2) or at dropout. An NLR ≥5 was associated with microvascular invasion (MVI), poorer tumor differentiation, and more advanced pathology on explant. Patients with an NLR ≥5 exhibited no differences in alpha-fetoprotein, tumor burden at listing, or number of locoregional therapies compared with patients with an NLR <5. After a median post-LT follow-up of 4.7 years, overall survival and recurrence rates were similar for patients with an NLR ≥5 versus patients with an NLR <5. The NLR changed frequently, and 47% of patients whose NLR2 was ≥5 had an NLR <5 by LT. The NLR was ≥5 in 47.6% of patients at dropout compared with 14.9% of patients undergoing LT. Although the NLR at LT correlated with MVI and tumor stage at explant, the NLR did not predict post-LT survival or HCC recurrence. The NLR appeared to be a relatively unstable inflammatory marker during the immediate 3 months before LT for HCC.
“Something like Bringing the Entire Life”: Muriel Rukeyser’s Personal, Poetic and Social Development in the 1930s

The publication of formerly “lost” works and the intensified scrutiny of others reveal new dimensions of Muriel Rukeyser’s remarkable relational thinking and invite reconsideration of which works a...
CAPE: A Content-Addressable Processing Engine

Processing-in-memory (PIM) architectures attempt to overcome the von Neumann bottleneck by combining computation and storage logic into a single component. The content-addressable parallel processing paradigm (CAPP) from the seventies is an in-situ PIM architecture that leverages content-addressable memories to realize bit-serial arithmetic and logic operations, via sequences of search and update operations over multiple memory rows in parallel. In this paper, we set out to investigate whether the concepts behind classic CAPP can be used successfully to build an entirely CMOS-based, general-purpose microarchitecture that can deliver manyfold speedups while remaining highly programmable. We conduct a full-stack design of a Content-Addressable Processing Engine (CAPE), built out of dense push-rule 6T SRAM arrays. CAPE is programmable using the RISC-V ISA with standard vector extensions. Our experiments show that CAPE achieves an average speedup of 14 (up to 254) over an area-equivalent (slightly under 9 mm2 at 7 nm) out-of-order processor core with three levels of caches.
The Effect of Acupuncture and Physiotherapy on Patients with Knee Osteoarthritis: A Randomized Controlled Study.

BACKGROUND Osteoarthritis is the most prevalent form of joint disease, and the most common location is the knee. OBJECTIVES The aim of this study was to determine the effect of acupuncture treatment and physiotherapy on pain, physical function, and quality of life (QOL) in patients with knee osteoarthritis (KOA). STUDY DESIGN This study was a prospective, randomized, controlled clinical trial. SETTINGS The research took place in the interventional pain unit of a tertiary center in a university hospital. METHODS One hundred patients with KOA were randomly divided into the acupuncture group and the physiotherapy group. Both treatments were given in 12 sessions over 6 weeks. Thirteen acupuncture points were selected for the knee. Local points were GB34, SP10, SP9, ST36, ST35, ST34, EX-LE2, EX-LE5, EXLE4, and distal (distant) points were defined as KI3, SP6, LI4, and ST41. The Visual Analog Scale (VAS) was used to measure pain intensity. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the 36-Item Short Form Health Survey (SF-36) were used to determine functional status and health-related QOL, respectively. All patients were evaluated at baseline, after the last treatment, and at the 12-week follow-up period. RESULTS There was no statistically significant difference between the acupuncture group and physiotherapy group in terms of pain, total WOMAC, and SF-36 levels at baseline, after treatment, and at the 12th week after treatment (P > 0.05). Both treatments significantly improved functional status (acupuncture, from 63.8 ± 20.81 to 53.72 ± 19.43; and physiotherapy, from 59.04 ± 21.49 to 52.28 ± 19.54; P < 0.05) and decreased the level of pain assessed by VAS (acupuncture, from 8.32 ± 1.61 to 5.54 ± 2.34; and physiotherapy, from 7.86 ± 1.9 to 5.68 ± 2.42; P < 0.05) at the 12-week follow-up of the study. There was no adverse advent related to therapeutic methods. LIMITATIONS Sham or placebo control groups are lacking in this study. CONCLUSIONS The acupuncture and physiotherapy performed twice weekly for 6 weeks have similar effects with regard to pain, functional status, and QOL. There were no significant differences between the acupuncture and physiotherapy groups in relief of pain, improved functional status, and QOL in the treatment of KOA. Both acupuncture and physiotherapy treatments were found to yield significantly superior results when compared with baseline values.
Natural History of HPV Infection Latency and Clearance

The majority of redetection of the same HPV type is likely due to sexual exposure. Other possible reasons are exposure to reservoirs in the partner or self and reactivation of a latent infection. Any prevalent infection is higher risk of cancer development than incident infection. Discussion should include the possibility of new infection, reactivation or transmission for another reservoir (e.g., partner, vagina, anus). But the importance is that a “new” infection preceded by a previously negative infection has little to no risk of cervical cancer and low risk of a significant precancer (ASCCP). However, the risk is not zero so follow-up is needed.
Outbreak Narrative in Pandemics: Resilience Building in Communicating About 1918 Influenza and SARS

This chapter examines pandemic communication from traditional media about two emerging pandemics, the 1918 Influenza and SARS in Hong Kong and Toronto, two of the epicenters. It focuses on how authorities, experts, and communities made sense and took action to cope with unknown health risks when little was known about the two pandemics. Focusing on pandemic communication from traditional media, it explores various ways resilience was built by different communities to better cope with the health risks brought by these two emerging pandemics, paying particular attention to expert-public communication, social scapegoating, racial profiling, networked collaboration, and community call for action.
Deep learning enabled ultra-fast-pitch acquisition in clinical X-ray computed tomography.

Objective In X-raycomputed tomography (CT), many important clinical applications may benefit from a fast acquisition speed. The helical scan is the most widely used acquisition mode in clinical CT, where a fast helical pitch can improve the acquisition speed. However, on a typical single-source helical CT (SSCT) system, the helical pitch p typically cannot exceed 1.5; otherwise, reconstruction artifacts will result from data insufficiency. The purpose of this work is to develop a deep convolutional neural network (CNN) to correct for artifacts caused by an ultra-fast pitch, which can enable faster acquisition speed than what is currently achievable. Methods A customized CNN (denoted as ultra-fast-pitch network (UFP-net)) was developed to restore the underlying anatomical structure from the artifact-corrupted post-reconstruction data acquired from SSCT with ultra-fast pitch (i.e., p ≥ 2). UFP-net employed residual learning to capture the features of image artifacts. UFP-net further deployed in-house-customized functional blocks with spatial-domain local operators and frequency-domain non-local operators, to explore multi-scale feature representation. Images of contrast-enhanced patient exams (n = 83) with routine pitch setting (i.e., p Results The UFP-net dramatically improved image quality over standard FBP at both ultra-fast-pitch settings. At p = 2, UFP-net yielded higher mean SSIM (> 0.98) with lower mean rRMSE ( 9.1%). Quantitative metrics at p = 3: UFP-net-mean SSIM [0.86, 0.94] and mean rRMSE [5.0%, 8.2%]; FBP-mean SSIM [0.36, 0.61] and mean rRMSE [36.0%, 58.6%]. Conclusion The proposed UFP-net has the potential to enable ultra-fast data acquisition in clinical CT without sacrificing image quality. This method has demonstrated reasonable generalizability over different body parts when the corresponding CT exams involved consistent base scan parameters.
Chapter 8 Insurrections

Abstract This essay develops an economic theory of insurrections. The decision-making agents in this theory are an incumbent ruler, a potential leader of an insurrection, and a large number of peasant or worker families. The essay distinguishes insurrections that attempt only to appropriate current income from revolutions, which are insurrections that attempt to effect permanent change in the distribution of income through the appropriation of sovereign power. The analysis shows how the technology of insurrection, together with a discount factor, determines whether there is an insurrection, the allocation of resources among productive activities, soldiering, and insurgency, and the probable outcome of an insurrection.
Absorption spectra of impurities in silicon—I: Group-III acceptors

Abstract The low-temperature absorption spectra of group-III impurities in silicon yield information about the ionization energies and excited states of the impurity centers. The optical values for the ionization energies of boron (0.046 eV) and indium (0.154 eV) are in good agreement with the thermal values, but the optical values for aluminum (0.67 eV) and gallium (0.71 eV) are appreciably larger than the thermal values. Variations in ionization energy among the group-III impurities are found to be accompanied by variations in the character of the excitation and photoionization spectra. The term schemes for the impurities are derived from the position of the excitation bands and the assumption that the 4p level is the same for all of the group-III impurities. Aside from the appearance of fine structure, the p-type states appear to fit a simple hydrogen model. From the positions of the p levels, an effective mass of 0.045 is calculated for holes using the expression for the energy levels of a hydrogen model. Variations in the oscillator strengths of the excitation bands among the group-III impurities are attributed to variations in the position and character of the 1s levels which arise from effects at the impurity atom that cause the simple effective-mass formalism to break down. The factors which should be included in a more complete theoretical treatment of the impurity centers are discussed.
A cellular decomposition algorithm for semi-algebraic sets

For any r≥1 and any i, 0≤i≤r, an i-dimensional cell (in Er) is a subset of r-dimensional Euclidean space Er homeomorphic to the i-dimensional open unit ball. A subset of Er is said to possess a cellular decomposition (c.d.) if it is the disjoint union of finitely many cells (of various dimensions). A semialgebraic set S (in Er) is the set of all points of Er satisfying some given finite boolean combination φ of polynomial equations and inequalities in r variables. φ is called a defining formula for S. A real algebraic variety, i.e. the set of zeros in Er of a system of polynomial equations in r variables, is a particular example of a semialgebraic set. It has been known for at least fifty years that any semialgebraic set possesses a c.d., but the proofs of this fact have been nonconstructive. Recently it has been noted that G. E. Collins' 1973 quantifier elimination algorithm for the elementary theory of real closed fields contains an algorithm for determining a c.d. of a semialgebraic set S given by its defining formula, apparently the first such algorithm. Specifically, each cell c of the c.d. C of S is itself a semialgebraic set, and for every c in C, a defining formula for c and a particular point of c are produced. In the present paper we provide a proof of this fact, our proof amounting to a description of Collins' algorithm from a theoretical point of view. We then show that the algorithm can be extended to determine the dimension of each cell in a c.d. and the incidences among cells. A computer implementation of the algorithm is in progress.
Toward a New Concept of Cell Motility: Cytoskeletal Dynamics in Amoeboid Movement and Cell Division

Publisher Summary This chapter reviews historical and current studies relevant to cytoskeletal dynamics, with emphasis on Dictyostelium cytoskeletons. Cytoskeletal dynamics is the cytoskeletal reorganization that occurs as a consequence of monomer–polymer transition and protein–protein as well as protein–membrane interactions. Actin constitutes as much as 10% of the total protein in nonmuscle cells. The dynamism of cytoplasm exhibits as a thixotropic transition with polymerization and crosslinking of the filaments through regulation of pH, calcium, and associating proteins. The cortical-gel contraction hypothesis predicted that actomyosin ATPase produces the energy of contraction in nonmuscle systems. The dynamics of nonmuscle-cell motility also manifests as projection rather than contraction. Many signal-transduction events relate significantly to cytoskeletal dynamics, such as chemotactic and growth stimulation that cause transient changes in cell shape, cell motility, and cell division. The actin cytoskeleton is probably regulated by the factors involved in the signal-transduction cascade. Profilin which is a low-molecular weight G-actin-binding protein, might play a significant role in regulating actin polymerization in the cytoplasm by binding to G-actin.
Stability of propofol with parenteral nutrient solutions during simulated Y-site injection

The stability of propofol in three parenteral nutrient (PN) solutions was studied. Nine combinations of three PN solutions (with amino acid concentrations of 1.5, 2.5, and 5.0%) and three propofol concentrations (0.5, 2.0, and 3.0 mg/mL) were prepared in triplicate and stored at 22 degrees C under fluorescent light. Duplicate samples were visually inspected for color changes, precipitation, or gas formation, and the pH of the samples was determined. These samples were evaluated for propofol content by high-performance liquid chromatography at zero, one, three, and five hours. The stability of the vehicle for propofol injection (similar in composition to fat emulsion) was evaluated by visual inspection, pH determination, and particle-size measurements at zero, one, three, and five hours. The concentration of propofol in all of the propofol-PN combinations remained greater than 90% of the initial concentration except for the combination of propofol 0.5 mg/mL and the 1.5% amino acid PN solution, which contained only 72% of the initial propofol concentration five hours after the start of the study. Visual examination revealed no evidence of color change, precipitation, gas formation, creaming, or streaking in any of the propofol-PN solution combinations. No substantial changes in pH occurred. The particle size of the vehicle for propofol remained relatively constant throughout the study period. Propofol 2 and 3 mg/mL was stable for five hours during simulated Y-site injection with PN solutions containing 1.5, 2.5, and 5% amino acids. Propofol 0.5 mg/mL was stable during simulated Y-site injection with the same PN nutrition solutions for five hours, except for the solution containing 1.5% amino acid.
Development of a process for hermetic resistance welding of microelectronics packages using Taguchi experimental design techniques

The use of Taguchi experimental design techniques to develop a one-shot resistance welding process for sealing microelectronics packages is discussed. After evaluation, four factors (process parameters) and three interactions between the factors were selected for analysis. The Taguchi L8 array used for the evaluation required eight experiments. Two devices were sealed in each of the experiments and were subjected to fine and gross leaky hermeticity testing according to MIL-STD-883. A second four-experiment evaluation was run to optimize the parameters selected in the first evaluation, and then a confirmation run of 10 devices was assembled. All devices from the second evaluation and the conformation run passed lead check and looked good visually. To date, 70 out of 71 devices sealed using this process passed lead check (99% yield). >
Unfolding transitions of fibronectin and its domains. Stabilization and structural alteration of the N-terminal domain by heparin.

Changes in the conformational state of human plasma fibronectin and several of its fragments were studied by fluorescence emission, intrinsic fluorescence polarization and c.d. spectroscopy under conditions of guanidinium chloride-and temperature-induced unfolding. Fragments were chosen to represent all three types of internal structural homology in the protein. Low concentration (less than 2 M) of guanidinium chloride induced a gradual transition in the intact protein that was not characteristic of any of the isolated domains, suggesting the presence of interdomain interactions within the protein. Intermediate concentrations of guanidinium chloride (2-3 M) and moderately elevated temperatures (55-60 degrees C) induced a highly co-operative structural transition in intact fibronectin that was attributable to the central 110 kDa cell-binding domain. High temperatures (greater than 60 degrees C) produced a gradual unfolding in the intact protein attributable to the 29 kDa N-terminal heparin-binding and 40 kDa collagen-binding domains. Binding of heparin to intact fibronectin and to its N-terminal fragment stabilized the proteins against thermal unfolding. This was reflected in increased delta H for the unfolding transitions of the heparin-bound N-terminal fragment, as well as decreased accessibility to solvent perturbants of internal chromophores in this fragment when bound to heparin. These results help to account for the biological efficacy of the interaction between the fibronectin N-terminal domain and heparin, despite its relatively low affinity.
Non-Gaussian Halo Bias Beyond the Squeezed Limit

Primordial non-Gaussianity, in particular the coupling of modes with widely different wavelengths, can have a strong impact on the large-scale clustering of tracers through a scale-dependent bias with respect to matter. We demonstrate that the standard derivation of this non-Gaussian scale-dependent bias is in general valid only in the extreme squeezed limit of the primordial bispectrum, i.e. for clustering over very large scales. We further show how the treatment can be generalized to describe the scale-dependent bias on smaller scales, without making any assumptions on the nature of tracers apart from a dependence on the small-scale fluctuations within a finite region. If the leading scale-dependent bias $\ensuremath{\Delta}b\ensuremath{\propto}{k}^{\ensuremath{\alpha}}$, then the first subleading term will scale as ${k}^{\ensuremath{\alpha}+2}$. This correction typically becomes relevant as one considers clustering over scales $k\ensuremath{\gtrsim}{10}^{\ensuremath{-}2}h\text{ }\text{ }{\mathrm{Mpc}}^{\ensuremath{-}1}$.
Designing dynamics and control of isotropic Gough-Stewart micromanipulators

A new, seven parameter class of micromanipulators is found with decoupled dynamics. The flexibility of the new class is demonstrated by designing a Stewart platform with fully equalized and decoupled dynamics (i.e., all resonant frequencies are equal). Although this has been attempted before by other researchers, it has not been previously accomplished. The ability to design the dynamics so they are amenable to control leads to significant increases in closed loop performance and robustness. The dynamically decoupled and equalized manipulator is compared to an asymmetric manipulator in closed loop. Even though both manipulators control the same payload over the same bandwidth with exactly the same struts, the H∞ controller for the equalized manipulator is five times less sensitive to worst case disturbances than the H∞ controller for the asymmetric manipulator. Moreover, the decoupling facilitates the design of Nyquist stable compensators which give the decoupled manipulator one hundred times higher performance at low frequencies. This greatly increased performance and robustness requires implementation of only the six compensators along the diagonal of the six degree-of-freedom system, versus implementation of all 36 compensators for the asymmetrical manipulator.
A Theoretical Analysis for the Effect of Substrate Elasticity on Cellular Adhesion

Cell behavior is mediated by variety of physiochemical properties of extracellular matrix (ECM). Material composition, surface chemistry, roughness, and distribution pattern of cell adhesive proteins are among the ECM properties which are known to modulate various cellular physiological functions. Mechanical stiffness of ECM in particular is found to be a major regulator for multiple aspects of cellular function. Experiments show that cells in general, exhibit an apparent adhesion preference for stiffer substrates with a larger projected spread area with increasing the substrate stiffness. In addition, it seems that the effect of substrates elasticity is strongly coupled with adhesivity of the substrate; on relatively stiff substrates the spread area of the cells exhibits strong biphasic dependence to the changes in ligand density, whereas on soft substrates their limited spreading is much less sensitive to the density of surface ligands. This study aims to propose a theoretical basis for the interplay between substrate elasticity and cellular adhesion, using an equilibrium thermodynamic model. Within this framework, the equilibrium contact area is assumed to ensure minimization of the free energy contributed by interfacial adhesive and repulsive interactions between the membrane and substrate as well as the deformation of cell and substrate. Hence, this thermodynamic model overlooks the contribution of intracellular signaling or actively regulated cytoskeleton and assumes that cell adhesion is solely a result of the balance between the membrane-substrate repulsive potentials, stored elastic energy, binding enthalpy, and mixing entropy of mobile receptors. The predictions of this purely mechanistic model for cell adhesion qualitatively follow the experimental results featuring the variation of cell spread area on compliant bio-adhesive substrates. This suggests that the mechanistic pathways inherent to membrane-substrate interactions may be equally important as intracellular signaling pathways to mediate the cellular adhesion.Copyright © 2010 by ASME
Comparison of outcomes after laparoscopic adjustable gastric banding in African-Americans and whites.

Abstract Background Race may affect outcomes after bariatric surgery. This study compares outcomes in terms of weight loss and comorbidity resolution between African-Americans and whites after laparoscopic adjustable gastric banding (LAGB). Methods Data from 959 patients undergoing LAGB between July 2001 and July 2004 were prospectively collected and entered into an electronic registry. Propensity score matching analysis was used to match whites to African-Americans on the basis of age, gender, and preoperative body mass index (BMI). Preoperative comorbidities (diabetes, hypertension, obstructive sleep apnea, hypercholesterolemia, and hypertriglyceridemia) were also compared. Operative time (OR), length of stay (LOS), comorbidity resolution, and percent excess weight loss (%EWL) at 1, 2, and 3 years were analyzed. All data were updated through May 2006. Results A total of 65 white LAGB patients were matched to 58 African-American LAGB patients on the basis of age, gender, and preoperative BMI. The preoperative mean age and BMI were 37 ± 19 years and 47 ± 7 kg/m 2 , respectively. A total of 55% of the white group and 64% of the African-American group had one or more comorbidities ( P = NS). Median OR time and LOS were similar in both groups: 50 minutes and 23 hours, respectively. The majority of patients in both groups had major improvement or resolution of one or more comorbidities (61% whites vs 77% African-Americans, P = NS). There was, however, a significant difference in %EWL between whites and African-Americans at each time interval (49% vs 39% at 1 year; 55% vs 44% at 2 years; 52% vs 41% at 3 years; P Conclusion Despite the disparity in weight loss with the LAGB in African-Americans and whites, both patient populations experienced a similar improvement/resolution of obesity-related comorbidities.
Orthodoxy, Islam, and the desecularization of Russia's state schools

This article explores the social origins and consequences of Orthodox-Muslim tensions surrounding the attempts to find a place for religion in Russia's state schools. It demonstrates that the Orthodox-Muslim tensions are an inevitable outcome of what we define as Russia's pattern of “desecularization from above.” The attempts to restore religious education are carried out by alliances of top religious and political elites, which almost by default focus on the state-run schools. These attempts run into serious social and institutional constraints, and generate considerable Orthodox-Muslim tensions and controversies spilling over to public opinion. On the surface, the Orthodox-Muslim tensions often appear in the form ironically resembling “culture wars” between religious traditionalists and secularists in the West. Our survey data indicate that public support for religious instruction in state-run schools has reached high levels and is infused with a noticeable element of religious intolerance. We predict that further attempts to desecularize Russia's state schools “from above” may have destabilizing effects in society and fuel ethno-religious tensions.
Afferent nerve endings in the urinary bladder of the cat

In five cats, sacral dorsal rhizotomies were performed, alone or in conjunction with sympathetic nerve transections. Urinary bladders, collected 7, 10, or 30 days following the nerve transections, were sectioned and stained by the Holmes silver nitrate and the Nauta and Gygax methods and examined under the light microscope. Degenerative changes occurred in bladders of all the cats permitting an assessment of the appearance and distribution of vesical sensory endings. Degenerated myelinated axons and nerve terminals were found bilaterally in bladders, although they were more numerous ipsilateral to the transections. Within the muscle coat, degenerated endings were found in the perifascicular connective tissue, and less frequently, on the surface of muscle fascicles; endings were not seen among the muscle cells within a fascicle. Sensory endings were identified in the subserosa and lamina propria but not in transitional epithelium. Except for an occasional Paccinian corpuscle, encapsulated endings were not found. Afferent endings in the bladder appeared to be non-encapsulated and without terminal fiber modifications.
ESCA studies of cross-linked poly(ethylene oxide)/polysiloxane networks

Abstract Networks of cross-linked poly(ethylene oxide) and a polyether-substituted polysiloxane were synthesized containing (i) variations of PEO content, (ii) PEO systematically varied from low to high molecular weight, and (iii) pentafunctional glycidoxy derivitized siloxane oligomers which acted as cross-linking units for both polymer components. Surface chemical analysis by ESCA demonstrated improved PEO surface coverage with increasing PEO content and molecular weight. This observation and the relative enhancement of surface silicon content with respect to the calculated bulk value were interpreted in terms of free energy minimization, chain overlap, and phase mixing.
The "Right Stuff" Gone Wrong: Vietnam Veterans and the Social Construction of Post-Traumatic Stress Disorder:

This paper presents a social constructionist account of post-traumatic stress disorder (PTSD). Its account of PTSD's multi-faceted origins begins with the efforts of the Nixon Administration to discredit of the voice of anti-war veterans following the fall, 1969, Moratorium Days against the war. Subsequently, mental health professionals frame veteran political behavior within a medical discourse, transporting the concepts alienation, survivor guilt, and flashbacks into the PTSD literature from other contexts. The New York Times plays a critical role in legitimating PTSD.