cssi/SciSciGPT-SciSciNet huggingface dataset:
Cooperation and spatial self-organization determine ecosystem function for polysaccharide-degrading bacteria

Abstract The recycling of particulate organic matter (POM) by microbes is a key part of the global carbon cycle, one which is mediated by the extracellular hydrolysis of polysaccharides and the production of public goods that can trigger social behaviors in bacteria. Despite the potential importance of these microbial interactions, their role in regulating of ecosystem function remains unclear. In this study, we developed a computational and experimental model system to address this challenge and studied how POM depolymerization rate and carbon use efficiency –two main ecosystem function parameters– depended on social interactions and spatial self-organization on particle surfaces. We found an emergent trade-off between rate and efficiency resulting from the competition between oligosaccharide diffusion and cellular uptake, with low rate and high efficiency being achieved through cell-to-cell cooperation between degraders. Bacteria cooperated by aggregating in cell-clusters of ∼10-20µm, where cells were able to share public goods. This phenomenon, which was independent of any explicit group-level regulation, led to the emergence of critical cell concentrations below which degradation did not occur, despite all resources being available in excess. By contrast, when particles were labile and turnover rates were high, aggregation promoted competition and decreased the efficiency of carbon utilization. Our study shows how social interactions and cell aggregation determine the rate and efficiency of particulate carbon turnover in environmentally relevant scenarios. Significance Statement Microorganisms can cooperate by secreting public goods that benefit local neighbors, however, the impact of cooperation on ecosystem functions remains poorly constrained. We here pair computation and experiment to show that bacterial cooperation mediates the degradation of polysaccharide particles recalcitrant to hydrolysis in aquatic environments. On particle surfaces, cooperation emerges through the self-organization of cells into ∼10-20µm clusters that promote cooperative uptake of hydrolysis products. The transition between cooperation and competition in aggregates is mitigated by individual cell behaviors such as motility and chemotaxis, that promote reorganization on the particle surface. When cooperation is required, the degradation of recalcitrant biopolymers can only take place when degraders exceed a critical cell concentration, underscoring the importance of microbial interactions for ecosystem function.
Evolution of an Electronic Health Record Based-Human Immunodeficiency Virus (HIV) Screening Program in an Urban Emergency Department for Diagnosing Acute and Chronic HIV Infection.

Abstract Background Since 2006, Centers for Disease Control and Prevention guidelines recommend routine opt-out human immunodeficiency virus (HIV) testing among sexually active 13- to 64-year-olds. Earlier diagnosis and treatment of HIV infection reduces morbidity and mortality and can limit transmission to others. Objective Our aim was to increase HIV testing, diagnosis, and linkage to care in the emergency department (ED). Methods Beginning May 4, 2015, we utilized our electronic health record (EHR) to enhance HIV testing in patients seen in the Rush University Medical Center emergency department in Chicago, IL, who were 13–64 years of age, did not have HIV listed on their problem list, and did not have an HIV antigen/antibody (Ag/Ab) test in the EHR within the past rolling 12-month period. Strategies included use of a “Best Practice Advisory” and later auto-order screening linked to a complete blood count order. Results Our baseline HIV test rate was 2.5% of the target population by age (average of 93 tests per month). From May 4, 2015 to January 31, 2019, 137,749 patients of 240,091 ED visits met our test criteria and 23,588 (17.1% of the target population) HIV Ag/Ab tests were performed, resulting in 164 positive tests. We identified 18 acute seroconverters, 51 new chronically infected persons, and 95 known infected, many of who had not disclosed their status. Our positive test rate was 0.70%, which dropped to 0.29% if only newly diagnosed individuals were counted. Conclusions EHR enhancements in a large urban ED identifies both newly diagnosed acute and chronically HIV-infected persons. Identification of previously diagnosed patients offers an opportunity to relink them to care.
Prehistoric Population Change within the Mt. Trumbull, AZ, Area

Recent archaeological research in the Mt. Trumbull region of northwestern Arizona has confirmed the presence of an unusually large number and variety of Virgin Branch Puebloan sites. Subsurface tes...
Going deeper: Automatic short-answer grading by combining student and question models

As various educational technologies have rapidly become more powerful and more prevalent, especially from the 2010s onward, the demand of automated grading natural language responses has become a major area of research. In this work, we leverage the classic student and domain/question models that are widely used in the field of intelligent tutoring systems to the task of automatic short-answer grading (ASAG). ASAG is the process of applying natural language processing techniques to assess student-authored short answers, and conventional ASAG systems often mainly focus upon student answers, referred as answer-based. In recent years, various deep learning models have gained great popularity in a wide range of domains. While classic machine learning methods have been widely employed to ASAG, as far as we know, deep learning models have not been applied to it probably because the lexical features from short answers provide limited information. In this work, we explore the effectiveness of a deep learning model, deep belief networks (DBN), to the task of ASAG. Overall, our results on a real-world corpus demonstrate that 1) leveraging student and question models to the conventional answer-based approach can greatly enhance the performance of ASAG, and 2) deep learning models such as DBN can be productively applied to the task of ASAG.
Dual blockade of IL-6 and CTLA-4 regresses pancreatic tumors in a CD4+ T-cell-dependent manner.

Abstract Pancreatic ductal adenocarcinoma (PDAC) is exceptionally resistant to immune checkpoint inhibition (ICI). We previously reported that elevated systemic interleukin-6 (IL-6) and increased numbers of T cells positive for circulating cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) correlate with worse overall survival in patients with PDAC. We postulated that combined blockade of IL-6 and CTLA-4 would significantly enhance anti-tumor immune responses to PDAC. Dual blockade of IL-6 and CTLA-4 in immune competent mice bearing subcutaneously injected pancreatic tumors significantly inhibited tumor growth, accompanied by overwhelming T cell infiltration. Therapeutic efficacy was confirmed in an orthotopic murine model of pancreatic cancer and T cell depletion studies unveiled a unique dependence on CD4+ T cells for anti-tumor activity of dual IL-6 and CTLA-4 blockade. In vitro studies utilizing T cells from a TRP-1 transgenic mouse as an antigen-specific model system demonstrate this combination therapy elicits increased IFN-γ production by activated CD4+ T cells. Additionally, IFN-γ stimulation of pancreatic tumor cells in vitro profoundly increased tumor cell production of CXCR3 specific chemokines (CXCL10 and CXCL9). Further studies blocking CXCR3 in the presence of combined IL-6 and CTLA-4 blockade prevented orthotopic tumor regression, demonstrating a dependence on the CXCR3 axis for anti-tumor efficacy. We also found combination therapy increased intratumoral CD4+ T cells and elicited systemic changes in T-helper subsets. These data represent the first report of IL-6 and CTLA-4 blockade as a means to regress pancreatic tumors with defined operative mechanisms of efficacy. Given these results, this therapeutic combination has potential for immediate clinical translation. One Sentence Summary Blockade of interleukin-6 in pancreatic cancer enhances CTLA-4 immune checkpoint inhibition to regress tumors in a CD4+ T cell and CXCR3-dependent manner.
Gynecologic cancer in pregnancy.

Abstract Cancer complicates 1 in 1000 pregnancies. Multidisciplinary consensus comprised of Gynecologic Oncology, Pathology, Neonatology, Radiology, Anesthesiology, Maternal Fetal Medicine, and Social Work should be convened. Pregnancy provides an opportunity for cervical cancer screening, with deliberate delays in treatment permissible for early stage carcinoma. Vaginal delivery is contraindicated in the presence of gross lesion(s) and radical hysterectomy with lymphadenectomy at cesarean delivery is recommended. Women with locally advanced and metastatic/recurrent disease should commence treatment at diagnosis with chemoradiation and systemic therapy, respectively; neoadjuvant chemotherapy to permit gestational advancement may be considered in select cases. Most adnexal masses are benign and resolve by the second trimester. Persistent, asymptomatic, benign-appearing masses can be managed conservatively; surgery, if indicated, is best deferred to 15–20 weeks, with laparoscopy preferable over laparotomy whenever possible. Benign and malignant germ cell tumors and borderline tumors are occasionally encountered, with unilateral adnexectomy and preservation of the uterus and contralateral ovary being the rule. Epithelial ovarian cancer is exceedingly rare. Ultrasonography and magnetic resonance imaging lack ionizing radiation and can be employed to evaluate disease extent. Tumor markers, including CA-125, AFP, LDH, inhibin-B, and even CEA and shCG may be informative. If required, chemotherapy can be administered following organogenesis during the second and third trimesters. Because platinum and other anti-neoplastic agents cross the placenta, chemotherapy should be withheld after 34 weeks to avoid neonatal myelosuppression. Bevacizumab, immune checkpoint inhibitors, and PARP inhibitors should be avoided throughout pregnancy. Although antenatal glucocorticoids to facilitate fetal pulmonary maturation and amniotic fluid index assessment can be considered, there is no demonstrable benefit of tocolytics, antepartum fetal heart rate monitoring, and/or amniocentesis. Endometrial, vulvar, and vaginal cancer in pregnancy are curiosities, although leiomyosarcoma and the dreaded twin fetus/hydatidiform mole have been reported. For gynecologic malignancies, pregnancy does not impart aggressive clinical behavior and/or worse prognosis.
Perinatal Health Outcomes Following a Community Health Worker-Supported Home-Visiting Program in Rochester, New York, 2015-2018.

We evaluated the effectiveness of a community health worker–supported home visitor program on perinatal outcomes of 455 at-risk pregnant women with program data merged with electronic medical recor...
Automatic Text Summarization of COVID-19 Medical Research Articles using BERT and GPT-2

With the COVID-19 pandemic, there is a growing urgency for medical community to keep up with the accelerating growth in the new coronavirus-related literature. As a result, the COVID-19 Open Research Dataset Challenge has released a corpus of scholarly articles and is calling for machine learning approaches to help bridging the gap between the researchers and the rapidly growing publications. Here, we take advantage of the recent advances in pre-trained NLP models, BERT and OpenAI GPT-2, to solve this challenge by performing text summarization on this dataset. We evaluate the results using ROUGE scores and visual inspection. Our model provides abstractive and comprehensive information based on keywords extracted from the original articles. Our work can help the the medical community, by providing succinct summaries of articles for which the abstract are not already available.
Does Model Ethnicity Matter in International Advertising? A Literature Review on Model Ethnicity and Related Topics: An Abstract

A literature review was conducted surrounding model ethnicity in the context of international advertising. Related literature and research are additionally reviewed in order to understand the diverse views and evaluations of model ethnicity in the international context. Varying factors can affect a viewer’s interpretation of ethnic model image, such as the level and strength of consumer ethnic identification, perceived or real threats to identity motives, or an individual’s culturally influenced self-concept. The literature was divided into four predominant research topics, and they are as follows: ethnic minorities in a majority region; a Western vs. Eastern context; beauty ideals and roles; and model ethnicity effects on product evaluations. Each of the four main topics is divided into subtopics and a decision tree is presented in order to organize and categorize the extant research. Determining the effectiveness of model ethnicity in advertising practice is a complex problem as many factors contribute to the viewer’s perception and subsequent evaluation of the advertisement.
Mammal functional diversity and habitat heterogeneity: Implications for hominin habitat reconstruction.

Abstract Hominin habitats are frequently described as ‘mosaic’ based on interpretations of fossil assemblages comprising taxa with divergent functional adaptations (e.g., both grazers and browsers). This interpretation rests on an assumption that mammal functional diversity is positively associated with habitat heterogeneity. We test this assumption using modern mammal data for 141 sites in Africa. Species average body mass and locomotor and dietary information was compiled for all species >500 g. The functional diversity of each species assemblage was measured using five metrics: locomotor richness, trophic richness, functional richness, functional divergence, and functional evenness. We used a high-resolution woody cover estimate for sub-Saharan Africa to compute the coefficient of variation of percentage of woody cover for each site. We used a published land cover classification to compute the number of habitat patches and the number of distinct habitat types at each site. Multiple regressions were conducted at 9 different spatial resolutions (pixel size ranging from 100 m to 30 km) to explore the relationship between functional diversity and habitat heterogeneity metrics. The overall number of species found at a site is strongly positively associated with functional richness, locomotor richness, and trophic richness at all spatial resolutions. The number of habitat types at a site and the density of habitat patches show a modest positive relationship with most functional diversity metrics at most spatial resolutions. The coefficient of variation in woody cover is a very poor predictor of functional diversity. The locomotor and trophic richness of mammal communities are positively associated with habitat heterogeneity and may be useful for reconstructing aspects of heterogeneity at hominin sites. However, the overall number of species is an important confounding variable, which in turn depends on the sample size of the overall fossil sample. Researchers should carefully consider impacts of sample size on faunal reconstructions of habitat heterogeneity.
A LRRK2 GTP Binding Inhibitor, 68, Reduces LPS-Induced Signaling Events and TNF-α Release in Human Lymphoblasts

Mutations in the leucine-rich repeat kinase-2 (LRRK2) gene cause autosomal-dominant Parkinson’s disease (PD) and contribute to sporadic PD. Common genetic variation in LRRK2 modifies susceptibility to immunological disorders including Crohn’s disease and leprosy. Previous studies have reported that LRRK2 is expressed in B lymphocytes and macrophages, suggesting a role for LRRK2 in immunological functions. In this study, we characterized the LRRK2 protein expression and phosphorylation using human lymphoblasts. Lipopolysaccharide (LPS), a proinflammatory agent, induced the increase of LRRK2 expression and kinase activities in human lymphoblasts in a time-dependent manner. Moreover, LPS activated the Toll-like receptor (TLR) signaling pathway, increased TRAF6/LRRK2 interaction, and elevated the phosphorylation levels of MAPK (JNK1/2, p38, and ERK1/2) and IkBα. Treatment with LRRK2 inhibitor 68 reduced LPS-induced TRAF6/LRRK2 interaction and MAPK and IkBα phosphorylation, thereby reducing TNF-α secretion. These results indicate that LRRK2 is actively involved in proinflammatory responses in human lymphoblasts, and inhibition of GTP binding by 68 results in an anti-inflammation effect against proinflammatory stimuli. These findings not only provide novel insights into the mechanisms of LRRK2-linked immune and inflammatory responses in B-cell-like lymphoblasts, but also suggest that 68 may also have potential therapeutic value for LRRK2-linked immunological disorders.
Same day discharge for pectus excavatum-is it possible?

Abstract Purpose The use of intercostal nerve cryoablation (INC) has been an effective modality for treating pain in patients undergoing pectus excavatum (PE) repair. This study sought to evaluate if PE patients undergoing Nuss procedures with INC and intercostal nerve block (INB) could safely be discharged the same day of surgery. Methods A prospective study with IRB approval of 15 consecutive patients undergoing PE Nuss repair with INC, INB, and an enhanced recovery after surgery (ERAS) protocol was conducted. The primary outcome measure was hospital length of stay (LOS) in hours. Secondary variables included same day discharge, postoperative complications, emergency department (ED) visits, urgent care (UC) visits, opioid use, and return to the operating room (OR). Results LOS averaged 11.9 h amongst 15 patients. Ten patients (66.7%) went home on postoperative day (POD) 0, and the rest went home on POD 1. No patients stayed in the hospital due to pain. Reasons for failure to discharge included urinary retention, drowsiness, vomiting, and anxiety, but not pain. No patients were readmitted to the ED. One patient visited UC for constipation. One patient had bar migration requiring return to the OR for revision. Ten (66.7%) patients did not use opioids after discharge. Conclusions Same day discharge is feasible and safe in PE patients undergoing Nuss procedure with INC and INB. INC with INB can adequately control pain without significant complications. Same day discharge can be safely considered for PE patients undergoing Nuss procedure with INC with INB. Type of study Prognosis study Level-of-evidence rating Level II
The new production theory for health care through clinical reengineering: a study of clinical guidelines--Part I.

Drucker writes that the emerging theory of manufacturing includes four principles and practices: statistical quality control, manufacturing accounting, modular organization, and systems approach. SQC is a rigorous, scientific method of identifying variation in the quality and productivity of a given production process, with an emphasis on improvement. The new manufacturing economics intends to integrate the production strategy with the business strategy in order to account for the biggest portions of costs that the old methods did not assess: time and automation. Production operations that are both standardized and flexible will allow the organization to keep up with changes in design, technology, and the market. The return on innovation in this environment is predicated on a modular arrangement of flexible steps in the process. Finally, the systems approach sees the entire process as being integrated in converting goods or services into economic satisfaction. There is now a major restructuring of the U.S. health care industry, and the incorporation of these four theories into health care reform would appear to be essential. This two-part article will address two problems: Will Drucker's theories relate to health care (Part I)? Will the "new manufacturing" in health care (practice guidelines) demonstrate cost, quality, and access changes that reform demands (Part II)?
VITAMIN B6 IN FAT METABOLISM.

Publisher Summary This chapter discusses the conflicting data on the relationship of the vitamin B 6 group, especially pyridoxine, to only a few of the many aspects of fat metabolism. The fatty acid composition of adipose tissue of pyridoxine-deficient rats is different from normals and that injections of insulin tended to reverse these changes. Pyridoxine-deficient rat serum and pancreatic tissue had lowered levels of insulin as measured by the epididymal fat pad method for insulin-like activity. Such evidence suggests that the lipid changes in pyridoxine-deficient rats might be related to the more complex relations of insulin insufficiency to fat metabolism. Indirect pathway is suggested by which fat metabolism can affect the utilization of vitamin B 6 and vice versa. The chapter mentions the known relationships between phospholipids and cholesterol esters on the one hand and fatty acid transport on the other.
A magnetoencephalography study of multi-modal processing of pain anticipation in primary sensory cortices

Pain anticipation plays a critical role in pain chronification and results in disability due to pain avoidance. It is important to understand how different sensory modalities (auditory, visual or tactile) may influence pain anticipation as different strategies could be applied to mitigate anticipatory phenomena and chronification. In this study, using a countdown paradigm, we evaluated with magnetoencephalography the neural networks associated with pain anticipation elicited by different sensory modalities in normal volunteers. When encountered with well-established cues that signaled pain, visual and somatosensory cortices engaged the pain neuromatrix areas early during the countdown process, whereas the auditory cortex displayed delayed processing. In addition, during pain anticipation, the visual cortex displayed independent processing capabilities after learning the contextual meaning of cues from associative and limbic areas. Interestingly, cross-modal activation was also evident and strong when visual and tactile cues signaled upcoming pain. Dorsolateral prefrontal cortex and mid-cingulate cortex showed significant activity during pain anticipation regardless of modality. Our results show pain anticipation is processed with great time efficiency by a highly specialized and hierarchical network. The highest degree of higher-order processing is modulated by context (pain) rather than content (modality) and rests within the associative limbic regions, corroborating their intrinsic role in chronification.
Research in Manufacturing Strategy: A Cross-Functional Perspective

One of the ubiquitous features of research in manufacturing strategy, is that there is invariably the need to consider the interfaces between the operations function and other functions in the firm. This is also true of practice in devising and implementing manufacturing strategy. Addressing these interfaces is thus valuable for research in strategy implementation in addition to strategy analysis and generation.
A Cognitive -Attributional Analysis of Stereotyping1

Publisher Summary The chapter summarizes evidence indicating that cognitive biases can result in the perceiver holding stereotypic conceptions of social groups; that is, cognitive mechanisms alone may be the foundation of perceived intergroup differences. The chapter reveals the significant role of cognitive mechanisms at several possible points in the overall attribution process. The cognitive orientation presented in the chapter provides a new perspective for understanding why stereotypes are so persistent over time and resistant to change. Stereotypes, as cognitive schemas, can influence the encoding, interpretation, retention, and retrieval of subsequently obtained information about members of stereotyped groups, along with the perceiver's causal attributions regarding the target person's behavior. The chapter discusses a number of cognitive biases, which have bearing on the stereotyping process. One of the primary challenges faced by researches in this field is the question of how these biases can be altered or modified in cases where they yield consequences hat reduce, rather than facilitate effectiveness. The chapter considers the question of what behavioral consequences result from the perceiver holding a stereotype of a particular group.
Mortgage Loan Rates and Deposit Costs: Are They Reliably Linked?

The deposit-cost markup theory of Jaffe and Rosen's type suggests that the cost of attracting funds determines prices (mortgage loan rates). Other equally plausible theories argue for the reverse chain of events, whereby mortgage loan rates induce changes in the deposit interest rates. We investigate these alternative hypotheses over the monthly period 1970 to 1994 using causality and cointegration tests with allowances for possible structural breaks. The results from error-correction models indicate the presence of bidirectional causality between the mortgage loan rates and the deposit interest rates. The results further show that the two variables exhibit a strong cointegrating relationship and that several factors play an important role in determining both variables. Our findings underscore the need to continue with efforts to develop and test multivariate error-correction models for the joint determination of the mortgage loan rate and the deposit interest rate.
Changes in fetal heart rate-uterine contraction patterns associated with eclampsia

Eclamptic seizures have been associated with fetal bradycardia and rapid onset or progression of labor. The fetal heart rate (FHR)-uterine contraction patterns during 14 seizures in 10 eclamptic patients were studied. Some seizures occurred in patients in whom magnesium sulfate levels were in the therapeutic range. The FHR response during an eclamptic episode was generally prolonged bradycardia. Uterine activity was noted to increase during seizure activity and preceded the fall in FHR. As seizure activity subsided, uterine hyperactivity diminished and the FHR rose, frequently demonstrating compensatory tachycardia. The clinical implications and possible pathophysiologic mechanisms of the FHR-uterine contraction observations are discussed.
How to Design Computer Security Experiments

In this paper, we discuss the scientific method and how it can be applied to computer security experiments. We reiterate a number of general scientific principles, such as falsifiable hypotheses, scientific controls, reproducible results, and data quality.
Path instabilities of air bubbles rising in clean water

Experiments are conducted to study the path and shape of single air bubbles (diameter range 0.10- 0.20cm) rising freely in clean water. The experimental results demonstrate that the bubble shape has a bistable state, i. e. the bubble chooses to be in spherical or ellipsoidal shape depending on its generation mechanism. The path of a spherical/ellipsoidal bubble is found to change from a straight path to a zigzag/spiral path via a supercritical/subcritical bifurcation when the Reynolds number of the bubble exceeds a threshold.
Molecular markers for breast cancer diagnosis, prognosis and targeted therapy

Precision medicine involves understanding the molecular drivers unique to an individual patient's cancer so that specific factors may be targeted with the goal of improved patient outcomes. The purpose of this article is to review standard of care and research grade (non-standard of care) biomarkers in breast cancer that may be useful for diagnosis, prognosis and targeted therapy. J. Surg. Oncol. 2015 111:81–90. © 2014 Wiley Periodicals, Inc.
Online Modified Greedy Algorithm for Storage Control Under Uncertainty

This paper studies the general problem of operating energy storage under uncertainty. Two fundamental sources of uncertainty are considered, namely the uncertainty in the unexpected fluctuation of the net demand process and the uncertainty in the locational marginal prices. We propose a very simple algorithm termed Online Modified Greedy (OMG) algorithm for this problem. A stylized analysis for the algorithm is performed, which shows that comparing to the optimal cost of the corresponding stochastic control problem, the sub-optimality of OMG is controlled by an easily computable bound. This suggests that, albeit simple, OMG is guaranteed to have good performance in cases when the bound is small. Meanwhile, OMG together with the sub-optimality bound can be used to provide a lower bound for the optimal cost. Such a lower bound can be valuable in evaluating other heuristic algorithms. For the latter cases, a semidefinite program is derived to minimize the sub-optimality bound of OMG. Numerical experiments are conducted to verify our theoretical analysis and to demonstrate the use of the algorithm.
Precision Velocity Measurements On Microwave Magnetic Envelope Solitons In Thin Films

Due to the balance between dispersion and nonlinear effects, microwave magnetic envelope (MME) solitons can be excited and propagated in yttrium iron garnet (YIG) films [ 13 Soliton characteristics have been elucidated from experimental output peak power vs input peak power profiles, threshold powers vs input pulse width, and phase properties [2, 31 These characteristics could be modeled, with varying degrees of success, from the nonlinear Schrodmger equation. The one fundamental soliton property which has not yet been examined in detail is the propagation velocity. Recent work by Slavin [3] can be used to predict the velocities for MME solitons The predicted changes in velocity for solitons, relative to the group velocity V, for low power MME pulses are small, on the order of a few percent only. The purpose of this work was to make precision velocity measurements for MME pulses as a function of input power and compare the results with theory The measurements were made for backward-volume-wave pulses propagated in a 7.2 pm YIG film in a two stripline transducer structure [I] The carrier frequency was 5 GHZ The static external magnetic field applied parallel to the propagation direction was 1088 Oe Measurements were made as a function of the input peak power P,, , input pulse width To, and transducer separation L. The output pulse shapes were generally quite different from the square input pulse shape, and this presented problems in precision velocity determinations. In order to solve this problem, the time of flight was defined as the time from the input pulse center position in time to a time center position T, for the output pulse defined by T,= (jlU(L, i)l t dt) / jlU(L, t)ldt, where U(L, t) denotes the measured microwave pulse amplitude vs. time t at the pick-up ttansducer for a transducer separation L. Note that U refers to the voltage response which is proportional to the dynamic magnetization amplitude for the MME pulse One could also calculate T, in terms of the pulse power profile with Ureplaced by in the integrals. This change affects the computed values of T, by a few tenths of a nanosecond only.
Neutral proteinase activity ofCandida albicans

Neutral proteinase activity (pH optimum 6–7.5) was demonstrated in cell extracts of the yeast form ofCandida albicans H-317. Proteolytic activity which required activation by treatment with sodium dodecyl sulfate was measured by a colorimetric assay for Azocoll hydrolysis. The activity was inhibited by antipain, chymostatin, phenylmethylsulfonyl fluoride, andp-chloromercuribenzoate, but was not affected by ethylenediaminetetraacetate, leupeptin, or pepstatin A. These results give the first evidence of a neutral proteinase inC. albicans.
Variational calculation of the electronic density at surfaces

Abstract The applicability of variational principles for single-particle expectation values to the inhomogeneous electron gas at surfaces is demonstrated. Jellium metal surface densities, correct to second order, are determined by application of the formalism to the operator W= ∑ i δ(x i −x) . The surface dipole barrier thus obtained is shown to lead to essentially exact results over a substantial range of the variational parameter employed. The procedure for inclusion of the discrete ionic lattice is also indicated.
Interspecific relationships and the evolution of sexual dimorphism in pygmy sunfishes (Centrarchidae: Elassoma )

The genus Elassoma represents a small but unique component of the aquatic biodiversity hotspot in southeastern North America. We present the first phylogeny of the seven described species, corroborated by sequence data from mitochondrial and nuclear protein coding genes. This analysis reveals a Coastal Plain clade sister to the geographically isolated, and federally protected, Elassoma alabamae. The Coastal Plain clade contains the widespread E. zonatum, which is sister to a clade primarily restricted to lowland Neogene subprovinces. We analyzed morphometric data in a phylogenetic context to illustrate the evolution of sexual shape dimorphism within the genus. Sixteen univariate and three multivariate traits were tested for significant sexual dimorphism for each species, and relative transformation rates were inferred from the time tree. A simple index of interspecific sexual dimorphism revealed greater disparity among sympatric species comparisons than among allopatric comparisons. Results implicate geology as a primary factor influencing ecological diversification, and sexual selection as a mechanism reinforcing reproductive isolation in areas of secondary contact. We discuss putative roles of geological history and sexual selection in the generation and maintenance of the aquatic biodiversity gradient in southeastern North America.
The effect of temperature on certain physical properties of dental amalgam

Abstract Amalgams which solidify at 37 °C. show less setting expansion and greater flow than amalgams which solidify at 25 °C. Some amalgams manipulated according to the manufacturers' directions show a contraction within 24 hours at 37 °C. The clinical significance of slight dimensional changes in amalgam has been questioned.
A new look at bronchopulmonary dysplasia classification.

In reading the literature over many years regarding bronchopulmonary dysplasia (BPD), there has been an evolution of and some difficulties in the terminology of this important disease. The original definition1 of a supplemental oxygen requirement and radiographic changes at 28 days became problematic as the care and survival of less mature infants became the norm. The term 'chronic lung disease (CLD)' came along when very immature infants who clearly were developing BPD but were not yet 28 days needed to have a diagnosis. In addition, we then began to define BPD as 'supplemental oxygen at 36 weeks postmenstrual age'.2 This is a much better definition but not truly a 'term,' and, then, many neonatologists were reluctant to 'diagnose' BPD until 36 weeks postmenstrual age (PMA), encouraging the use of the less-specific term CLD prior to that age.
Ultrasonography in pain medicine: Future directions

This paper presents examples of potential future directions regarding the applications of ultrasonography in interventional pain management.
Surgical approaches to invasive adenocarcinoma of the gastroesophageal junction.

Despite a plethora of data, the optimal surgical approach to invasive adenocarcinoma of the gastroesophageal (GE) junction remains controversial. To quote Dr. Valerie Rusch, "Strong individual preferences and some degree of surgical mystique often govern the selection of operation for resection of GE junction adenocarcinomas."1 The first of these controversies is whether the optimal open surgical approach should be via the transabdominal, transthoracic (two-incision Ivor Lewis or three-incision McKeown), or transhiatal route. Proponents of the transthoracic or transhiatal routes have voiced strong opinions on the potential advantages and disadvantages of each approach (Table 1). It is clear from most large retrospective series that, in experienced hands, excellent results can be achieved by either approach. The principal advantage of the transthoracic route is the ability to perform a radical mediastinal lymphadenectomy en bloc with the primary tumor, the theory being that a more aggressive lymph node dissection would be associated with an improved long-term outcome. To date, however, this association of a more aggressive lymphadenectomy with improved outcome has remained elusive in most gastrointestinal malignancies, including esophageal cancer. Proponents of the transhiatal approach cite similar lymph node retrieval rates, the potential for lower short-term morbidity, and the potential for similar long-term outcomes.2 With the advent of newer technology, the controversy regarding the optimal surgical approach to adenocarcinoma of the GE junction has evolved in yet another direction, with proponents of a minimally invasive approach, citing even lower perioperative morbidity and mortality, again with comparable or even superior long-term oncologic results.
Propagation through a precipitation medium: Theory and measurement

The theory of propagation through a precipitation medium is based here on the differential propagation constant and two additional complex constants. The latter reduce to a single real parameter, the "canting angle," for certain simple models, for example, for a population of equioriented symmetrical scatterers. In a uniform medium the constants are closely related to the elements of an equivalent permittivity tensor. It is shown that the parameters can be determined from a sequence of depolarization measurements.
Novel Gaussianized vector representation for improved natural scene categorization

We present a novel Gaussianized vector representation for scene images by an unsupervised approach. Each image is first encoded as an ensemble of orderless bag of features. A global Gaussian Mixture Model (GMM) learned from all images is then used to randomly distribute each feature into one Gaussian component by a multinomial trial. The posteriors of the feature on all the Gaussian components serve as the parameters of the multinomial distribution. Finally, the normalized means of the features distributed in every Gaussian component are concatenated to form a supervector, which is a compact representation for each scene image. We prove that these supervectors observe the standard normal distribution. The Gaussianized vector representation is a more generalized form of the widely used histogram representation. Our experiments on scene categorization tasks using this vector representation show significantly improved performance compared with the histogram-of-features representation. This paper is an extended version of our work that won the IBM Best Student Paper Award at the 2008 International Conference on Pattern Recognition (ICPR 2008) (Zhou et al., 2008).
Morphology and laser damage studies by atomic force microscopy of e-beam evaporation deposited antireflection and high-reflection coatings

Atomic force microscopy (AFM) is a powerful tool for studying the surface morphology of dielectric thin film coatings. Results of AFM scanning of antireflection and high reflection coatings are presented. These results demonstrate the effectivenss of AFM in providing high resolution monitoring of processing defects, laser damage, and laser conditioning and aging in e-beam evaporation deposited films.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Multiple Scattering Analysis of Retinal Blood Oximetry

A recently developed instrument, the photographic eye oximeter (PEO), has been used to make extensive measurements of retinal blood oxygen saturation in rabbits. A model for the reflection of light from the ocular fundus is developed to account for the experimental results. This model is based on the multiple scattering of photons by red blood cells (rbc's) and enables three components of detected light to be distinguished, the coherently transmitted, the diffusely scattered into the detector cone, and the diffusely scattered out of the detector cone. The small diameter of these vessels, the wavelength bands selected for measurement, the large total scattering cross section, and the sharply forward peaked scattering pattern of the red blood cells causes the detected signal from the fundus to be composed primarily of light that has diffusely traversed the vessel twice, reflecting from a background layer after a first traverse. The light is attenuated by a saturation dependent molecular absorption. Equations are derived to enable the blood oxygen saturation to be calculated from photometrically measured quantities. A theoretical calibration line for the PEO is calculated and is shown to be in very good agreement with the experimental line, especially at high saturations.
Energetic Coupling of the Ligand Binding Domain to Pore Opening in NMDA Receptors

Agonist binding to NMDARs initiates an allosteric process that culminates in opening of the associated ion channel. The ligand binding domain (LBD) is a bilobed, clamshell-like structure. Agonist-induced closure of the LBD generates free energy which is transduced into opening of the ion channel, but how this linkage occurs is unknown. The M3 helix is the major pore-lining transmembrane helix and must be displaced for pore opening to occur. Hence, the M3-S2 linker, which couples the LBD to M3, may mechanically pull on M3, but this idea remains untested. By combining functional and structural approaches, we provide the first evidence in an intact glutamate receptor that the LBD mechanically pulls the M3-S2 linker, thus serving as a major driving force for pore opening. Insertions in the M3-S2 linker reduced gating in a manner largely independent of insertion site and that longer insertions progressively dampened the efficiency of pore opening. These manipulations had no apparent effects on LBD dynamics. We also found that the latency to first opening was increased by reducing the coupling capacity of M3-S2. All-atom molecular dynamics simulations on modeled GluN1/GluN2A receptors indicated that pore widening is intimately linked to M3-S2 length and that reductions in pore radius were comparable to the changes seen in open probability and latency to first opening. Across all experiments, the GluN2A subunit showed more dramatic effects, thus providing evidence for subunit-specific gating modalities during NMDAR activation. Using phi-type thermodynamic analyses we find that the GluN2A M3-S2 linker transfers more gating force and this precedes GluN1. These results suggest that gating in NMDARs involves a mechanical separation of the M3 helices by the M3-S2 linker.
Common Scab Trials of Potato Varieties and Advanced Selections at Three U.S. Locations

Common scab (CS), caused by Streptomyces spp., is a soil-borne bacterial disease of potato tubers which may cause superficial, raised, or pitted lesions. The results of screening potato germplasm for severity of CS can be variable, necessitating testing over multiple environments. The purposes of this study were to evaluate advanced germplasm from public potato breeding programs in different regions of the United States for their reaction to CS, estimate broad-sense heritability for resistance, and identify clones with stable resistance. Seventeen to 23 clones per year were evaluated at each of three locations (ID, ME, MN) from 2002 to 2007. After harvest, each tuber was scored for the percent of surface area covered with lesions and the type of lesion. These scores were converted to an area index (AI) and a lesion index (LI). AI, LI, and the arcsine √ proportion scabby tubers (PS) were analyzed as normally distributed responses. There were significant differences among clones for AI in 2 years, LI in 5 years, and PS in 3 years. There were significant clone x location interactions for AI and PS all 6 years, and LI in 5 years. Broad-sense heritability for AI, LI, and PS ranged from 0 to 0.78, 0.49 to 0.90, and 0.30 to 0.80, respectively. Evaluation at multiple sites remains important for characterizing the reaction of potato germplasm to CS.
Cytokines induce small intestine and liver injury after renal ischemia or nephrectomy

Patients with acute kidney injury (AKI) frequently suffer from extra-renal complications including hepatic dysfunction and systemic inflammation. We aimed to determine the mechanisms of AKI-induced hepatic dysfunction and systemic inflammation. Mice subjected to AKI (renal ischemia reperfusion (IR) or nephrectomy) rapidly developed acute hepatic dysfunction and suffered significantly worse hepatic IR injury. After AKI, rapid peri-portal hepatocyte necrosis, vacuolization, neutrophil infiltration and pro-inflammatory mRNA upregulation were observed suggesting an intestinal source of hepatic injury. Small intestine histology after AKI showed profound villous lacteal capillary endothelial apoptosis, disruption of vascular permeability and epithelial necrosis. After ischemic or non-ischemic AKI, plasma TNF-α, IL-17A and IL-6 increased significantly. Small intestine appears to be the source of IL-17A, as IL-17A levels were higher in the portal circulation and small intestine compared with the levels measured from the systemic circulation and liver. Wild-type mice treated with neutralizing antibodies against TNF-α, IL-17A or IL-6 or mice deficient in TNF-α, IL-17A, IL-17A receptor or IL-6 were protected against hepatic and small intestine injury because of ischemic or non-ischemic AKI. For the first time, we implicate the increased release of IL-17A from small intestine together with induction of TNF-α and IL-6 as a cause of small intestine and liver injury after ischemic or non-ischemic AKI. Modulation of the inflammatory response and cytokine release in the small intestine after AKI may have important therapeutic implications in reducing complications arising from AKI.
Excitotoxic and oxidative cross-talk between motor neurons and glia in ALS pathogenesis.

Excitotoxicity, resulting from deficiencies in astrocytic glutamate uptake, appears to play a crucial role in the pathogenesis of amyotrophic lateral sclerosis (ALS). However, factors underlying the highly selective pattern of motor neuron loss that is the hallmark of the disease, and those underlying the loss of astrocytic glutamate transport, remain unresolved. Recent studies have provided insights into both of these questions. Evidence suggests that damaging reactive oxygen species, which appear to be preferentially produced in motor neurons in response to excitotoxic activation, could exit the motor neurons and induce oxidative disruption of glutamate transport in surrounding astrocytes. This would exacerbate excitotoxic stress to motor neurons, resulting in a vicious cycle that could underlie disease progression. These observations provide a new understanding of ALS pathogenesis that integrates diverse clues into a unified model that is broadly applicable to different forms of the disease.
Wireless medium access control protocols

Technological advances, coupled with the flexibility and mobility of wireless systems, are the driving force behind the Anyone, Anywhere, Anytime paradigm of networking. At the same time, we see a convergence of the telephone, cable and data networks into a unified network that supports multimedia and real-time applications like voice and video in addition to data. Medium access control protocols define rules for orderly access to the shared medium and play a crucial role in the efficient and fair sharing of scarce wireless bandwidth. The nature of the wireless channel brings new issues like location-dependent carrier sensing, time varying channel and burst errors. Low power requirements and half duplex operation of the wireless systems add to the challenge. Wireless MAC protocols have been heavily researched and a plethora of protocols have been proposed. Protocols have been devised for different types of architectures, different applications and different media. This survey discusses the challenges in the design of wireless MAC protocols, classifies them based on architecture and mode of operation, and describes their relative performance and application domains in which they are best deployed.