cssi/SciSciGPT-SciSciNet huggingface dataset:
Defining roles of the sterol recognition region in Hedgehog cholesterolyation

The Hedgehog (Hh) signaling pathway plays an essential role during embryogenesis and when dysregulated, can lead to human cancer (basal cell carcinomas) and the most lethal form of juvenile medulloblastoma. Binding of the Hh ligand to its receptor Patched (Ptch) relieves inhibition of the GPCR protein Smoothened (Smo) leading to activation of the Gli transcription factors and changes in target gene expression. The Hh ligand is decorated with two covalent modifications, N‐terminal palmitoylation and C‐terminal cholesterolyation. Hh proteins are synthesized as approximately 45 kDa full‐length species, whereupon a unique process yields the mature morphogen: an autocatalytic cleavage that splits the protein in two and attaches cholesterol to the newly formed C‐terminus. Of the two approximately equal molecular weight cleavage products, the dually lipidated N‐terminal fragment (Hh‐N/“Hog” domain) constitutes the classical Hh morphogen, whereas the C‐terminus (Hh‐C/“Hint”) is responsible for the cleavage reaction. In order to elucidate the chemical mechanism of cholesterolyation, we have determined the roles of the previously uncharacterized sterol recognition region (SRR) in Hh proteins. Using bioinformatics, alanine scanning, and biochemical assays we have identified key motifs and specified residues of the SRR that are required for biochemical processing of Hh. These results provide a first in detail insights into the role of this unique small region of the Hh protein that is capable of cellular targeting and engaging cholesterol to generate an active Hh ligand. This work was supported by the Margaret E. Early Medical Research Trust.
Ontogenetic variation in thermal sensitivity shapes insect ecological responses to climate change

Insects have distinct life stages that can differ in their responses to environmental factors. We discuss empirical evidence and theoretical models for ontogenetic variation in thermal sensitivity and performance curves (TPCs). Data on lower thermal limits for development (T0) demonstrate variation between stages within a species that is of comparable magnitude to variation among species; we illustrate the consequences of such ontogenetic variation for developmental responses to changing temperature. Ontogenetic variation in optimal temperatures and upper thermal limits has been reported in some systems, but current data are too limited to identify general patterns. The shapes of TPCs for different fitness components such as juvenile survival, adult fecundity, and generation time differ in characteristic ways, with important consequences for understanding fitness in varying thermal environments. We highlight a theoretical framework for incorporating ontogenetic variation into process-based models of population responses to seasonal variation and climate change.
Work-Life Conflicts

A career in medicine is rife with work-life conflict for both women and men. Women in particular must make choices along their medical journey, the very characteristics of which might be considered drivers of work-life imbalance and burnout (specialty, work hours, income). Societal norms, albeit changing, often result in women being more heavily involved and invested in home and childcare responsibilities. Many physicians feel stigmatized if they take advantage of flexible policies. Personal characteristics such as commitment to self-care, the ability to self-promote and to set limits, as well as the lack of effective role models and mentors for women can further impede successful work-life integration. This chapter explores key drivers of work-life conflicts in medicine, differences among the specialties and between male and female physicians, reasons for greater distress among women, and potential solutions across the career lifespan.
A Genome-wide CRISPR Screen Reveals a Role for the Non-canonical Nucleosome-Remodeling BAF Complex in Foxp3 Expression and Regulatory T Cell Function.

Regulatory T (Treg) cells play a pivotal role in suppressing auto-reactive T cells and maintaining immune homeostasis. Treg cell development and function are dependent on the transcription factor Foxp3. Here, we performed a genome-wide CRISPR loss-of-function screen to identify Foxp3 regulators in mouse primary Treg cells. Foxp3 regulators were enriched in genes encoding subunits of the SWI/SNF nucleosome-remodeling and SAGA chromatin-modifying complexes. Among the three SWI/SNF-related complexes, the Brd9-containing non-canonical (nc) BAF complex promoted Foxp3 expression, whereas the PBAF complex was repressive. Chemical-induced degradation of Brd9 led to reduced Foxp3 expression and reduced Treg cell function in vitro. Brd9 ablation compromised Treg cell function in inflammatory disease and tumor immunity in vivo. Furthermore, Brd9 promoted Foxp3 binding and expression of a subset of Foxp3 target genes. Our findings provide an unbiased analysis of the genetic networks regulating Foxp3 and reveal ncBAF as a target for therapeutic manipulation of Treg cell function.
From the Employee Perspective: Organizations’ Administration of Internal Social Media and the Relationship between Social Media Engagement and Relationship Cultivation:

This study examined communication strategies used by organizations to encourage employee participation on internal social media and analyzed whether employees’ internal social media usage engenders...
Concussion Knowledge, Attitudes, and Self-Reporting Intentions in Youth Athletes.

CONTEXT Although it has been suggested that developmental and sociological factors play a role in concussion reporting, the empirical evidence related to this is limited. OBJECTIVE To examine the influences of sex, school level, school location, concussion-reporting history, and socioeconomic status on concussion-related knowledge, attitudes, and reporting intentions among middle school and high school athletes. DESIGN Cross-sectional study. SETTING Master students and High School athletes attending pre-participation examinations (PPEs) were asked to complete paper-based surveys. PATIENTS OR OTHER PARTICIPANTS Overall, 541 athletes representing 18 sports returned fully completed surveys. MAIN OUTCOME MEASURE(S) Outcomes were concussion-related knowledge, perceived seriousness, positive feelings about reporting, and self-reporting intentions. We examined group differences in these outcomes across levels of the explanatory variables of sex, school level (middle school versus high school), school location (urban versus rural), concussion self-reporting history (yes or no), and socioeconomic status (free or reduced-price lunch versus no free or reduced-price lunch) using Wilcoxon rank sum tests. Then we used multivariable ordinal logistic regression models to identify predictors of higher score levels for each outcome. Odds ratio (OR) estimates with 95% confidence intervals (CIs) excluding 1.00 were deemed significant. RESULTS Odds of higher levels of knowledge were higher in urban versus rural school student-athletes (ORAdjusted = 1.81; 95% CI = 1.03, 3.17), and lower in student-athletes on free or reduced-price lunch versus those not on free or reduced-price lunch (ORAdjusted = 0.52; 95% CI = 0.36, 0.77). Similarly, odds of higher levels of seriousness were lower in male versus female student-athletes (ORAdjusted = 0.48; 95% CI = 0.32, 0.72). Further, odds of higher levels of self-reporting intentions were lower among male versus female student-athletes (ORAdjusted = 0.53; 95% CI = 0.37, 0.75). CONCLUSIONS Developmental and sociological factors were differentially associated with concussion-related knowledge, attitudes, and self-reporting intentions. These results can inform medical providers, parents, and coaches with regard to context-specific clinical assessments of concussion symptoms.
Sieve-SDP: a simple facial reduction algorithm to preprocess semidefinite programs

We introduce Sieve-SDP, a simple facial reduction algorithm to preprocess semidefinite programs (SDPs). Sieve-SDP inspects the constraints of the problem to detect lack of strict feasibility, deletes redundant rows and columns, and reduces the size of the variable matrix. It often detects infeasibility. It does not rely on any optimization solver: the only subroutine it needs is Cholesky factorization, hence it can be implemented in a few lines of code in machine precision. We present extensive computational results on several problem collections from the literature, with many SDPs coming from polynomial optimization.
A Unique Subset: Idiopathic Intracranial Hypertension Presenting as Spontaneous CSF Leak of the Anterior Skull Base

Background Spontaneous cerebrospinal fluid (CSF) leaks represent a unique clinical presentation of idiopathic intracranial hypertension (IIH), lacking classical features of IIH, including severe headaches, papilledema, and markedly elevated opening pressures. Methods Following a single-institution retrospective review of patients undergoing spontaneous CSF leak repair, we performed a literature review of spontaneous CSF leak in patients previously undiagnosed with IIH, querying PubMed. Results Our literature review yielded 26 studies, comprising 716 patients. Average age was 51 years with 80.8% female predominance, and average body mass index was 35.5. Presenting symptoms included headaches (32.5%), visual disturbances (4.2%), and a history of meningitis (15.3%). Papilledema occurred in 14.1%. An empty sella was present in 77.7%. Slit ventricles and venous sinus stenosis comprised 7.7 and 31.8%, respectively. CSF leak most commonly originated from the sphenoid sinus (41.1%), cribriform plate (25.4%), and ethmoid skull base (20.4%). Preoperative opening pressures were normal at 22.4 cm H2O and elevated postoperatively to 30.8 cm H2O. 19.1% of patients underwent shunt placement. CSF leak recurred after repair in 10.5% of patients, 78.6% involving the initial site. A total of 85.7% of these patients were managed with repeat surgical intervention, and 23.2% underwent a shunting procedure. Conclusion Spontaneous CSF leaks represent a distinct variant of IIH, distinguished by decreased prevalence of headaches, lack of visual deficits, and normal opening pressures. Delayed measurement of opening pressure after leak repair may be helpful to diagnose IIH. Permanent CSF diversion may be indicated in patients exhibiting significantly elevated opening pressures postoperatively, refractory symptoms of IIH, or recurrent CSF leak.
Attrition of Thoroughbred and Standardbred racehorses at New York Racetracks due to exercise and non-exercise related fatalities during the 2016 - 2019 racing seasons.

ABSTRACT A longitudinal retrospective study was carried out to investigate the attrition of Thoroughbred (TB) and Standardbred (SB) horses racing at New York racetracks during the 2016 to 2019 seasons. The data were collected from the New York State Gaming Commission (NYSGC) Equine Breakdown, Death, Injury and Incident (EBDII), The Jockey Club InCompass Solutions, and The United States Trotting Association Pathway databases. Survival analysis was used to compare the predisposing factors by breed of the horse. The study included 431 horses (360 TB and 71 SB). There was a significant difference between the average incidence of attrition events per start for TB (0.304) and SB (0.035) horses. There was a significant difference in the median age to attrition between TB (4.2 years) and SB (7.5 years) horses. There was also a significant difference between the average number of starts to attrition for TB (13.6) and SB (125.5) horses. Among the causes of attrition events in the two breeds musculoskeletal injuries and medical conditions were significantly higher among TB horses, while sudden death was significantly higher among SB horses. The multivariate analysis showed that the hazard of attrition was affected by the age of the horse, age at first start, whether the horse was intact male, type of activity (racing training or other) and the breed of the horse. SB horses were less likely to experience attrition events in comparison to TB horses.
Algorithmic approach to the lymphatic leak after vascular reconstruction: a systematic review.

Background To date, there are no consensus guidelines for management of lymphatic leak in groin vascular reconstruction patients. The goal of this study is to review the relevant literature to determine alternatives for treatment and to design an evidence-based algorithm to minimize cost and morbidity and maximize efficacy. Methods A systematic review of the literature was conducted per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Two independent reviewers applied agreed-upon inclusion and exclusion criteria to eligible records. Studies that included patients who underwent groin dissection for oncologic diagnoses and level 5 data were excluded. Interventions were then categorized by efficacy using predetermined criteria. Results Our search yielded 333 records, of which eight studies were included. In four studies, the success of lymphatic ligation ranged from 75% to 100%, with average days to resolution ranging from 0 to 9. Conservative management in the form of elevation, compression, and bedrest may prolong time to resolution of lymphatic leak (14-24 days) and therefore cost. Conclusions The majority of patients should be offered early operative intervention in the form of lymphatic ligation with or without a primary muscle flap. If the patient is not an operative candidate, a trial of conservative management should be attempted before other nonsurgical interventions.
Social Work in Public Libraries: A Survey of Heads of Public Library Administrative Units

This paper reports the results of a survey of heads of public library administrative units concerning their experiences with and perceptions of the employment of social workers. Among respondents, ...
WE-EF-210-08: BEST IN PHYSICS (IMAGING): 3D Prostate Segmentation in Ultrasound Images Using Patch-Based Anatomical Feature

Purpose: Transrectal ultrasound (TRUS) is the standard imaging modality for the image-guided prostate-cancer interventions (e.g., biopsy and brachytherapy) due to its versatility and real-time capability. Accurate segmentation of the prostate plays a key role in biopsy needle placement, treatment planning, and motion monitoring. As ultrasound images have a relatively low signal-to-noise ratio (SNR), automatic segmentation of the prostate is difficult. However, manual segmentation during biopsy or radiation therapy can be time consuming. We are developing an automated method to address this technical challenge. Methods: The proposed segmentation method consists of two major stages: the training stage and the segmentation stage. During the training stage, patch-based anatomical features are extracted from the registered training images with patient-specific information, because these training images have been mapped to the new patient’ images, and the more informative anatomical features are selected to train the kernel support vector machine (KSVM). During the segmentation stage, the selected anatomical features are extracted from newly acquired image as the input of the well-trained KSVM and the output of this trained KSVM is the segmented prostate of this patient. Results: This segmentation technique was validated with a clinical study of 10 patients. The accuracy of our approach was assessed using the manual segmentation. The mean volume Dice Overlap Coefficient was 89.7±2.3%, and the average surface distance was 1.52 ± 0.57 mm between our and manual segmentation, which indicate that the automatic segmentation method works well and could be used for 3D ultrasound-guided prostate intervention. Conclusion: We have developed a new prostate segmentation approach based on the optimal feature learning framework, demonstrated its clinical feasibility, and validated its accuracy with manual segmentation (gold standard). This segmentation technique could be a useful tool for image-guided interventions in prostate-cancer diagnosis and treatment. This research is supported in part by DOD PCRP Award W81XWH-13-1-0269, and National Cancer Institute (NCI) Grant CA114313.
Analysis of Braking and Steering Performance in Car- Following Scenarios

This paper presents recent results of on-going research to build new maps of driver performance in car-following situations. The novel performance map is comprised of four driving states: low risk, conflict, near crash, and crash imminent - which correspond to advisory warning, crash imminent warning, and crash mitigation countermeasures. The paper addresses two questions dealing with the approach to quantify the boundaries between the driving states: (1) Do the quantified boundaries strongly depend on the dynamic scenario encountered in the driving environment? and (2) Do the quantified boundaries vary between steering and braking driver responses? Specifically, braking and steering driver performances are examined in two car-following scenarios: lead vehicle stopped and lead vehicle moving at lower constant speed. The analysis was conducted on experimental data collected from test track studies to develop a fundamental understanding of drivers' last-second braking and steering performance. The results of last-second braking performance analysis showed that the quantified boundaries depend on the dynamic scenario. On the other hand, the quantified boundaries were independent of the specific dynamic scenario based on the analysis of last-second steering performance. Finally, the quantified boundaries varied between braking and steering responses since drivers initiated last-second braking maneuvers at generally longer distances that last-second steering maneuvers.
The Rule Of Law Is Not Enough

One of the most fundamental and cherished concepts advocated for any government is that “rightness” should be defined by the “rule of law”; that is, the basic design and operations of governments as stated in constitutions, enacted laws, the enduring structure of the national justice system, a body of common laws and precedents, and a legal structure of governments in which the powers and authorities are both authorized and limited. Citizen’s rights are protected and their obligations defined under these laws, and usually include the right to take legal action to protect themselves. The rule of law has long been considered as the principal means by which governments are kept within proper limits. Even totalitarian governments attempt to hide their arbitrary motives by issuing finely worded constitutions that appear to guarantee a rule of law but that in reality are doomed to be disregarded at the pleasure of the State. Charles F. Bingman spent 30 years as a U. S. government official in NASA, the Transportation Department and the Executive Office of the President, and he has since taught public management at the George Washington University and the Johns Hopkins U. Washington Center. He has undertaken consulting assignments in more than a dozen countries including China. His most recent book is “Why Governments Go Wrong”, iUniverse, 2006. [1] Concept of the supremacy of regular, as opposed to arbitrary, power; c. the exercise of these powers by those in authority; d. the doctrine that any person is subject to the ordinary laws of the region; e. the As used in this paper, the rule of law is: a. A set of substantive legal principles and laws; b. the doctrine that the general constitutional/legal principles are the result of judicial decisions determining the rights of private individuals in the courts.
INTRA-UTERINE UNDERNUTRITION AND BRAIN DEVELOPMENT

The guinea pig, like the human, initiates the period of rapid brain growth in utero and thus provides a model for measuring the effects of maternal malnutrition on intra-uterine brain growth. In these studies the newborn of undernourished guinea pig mothers showed significant reductions in body weight and brain weight, cellularity, protein, cholesterol, cerebroside, and sulfatide contents. The reductions in wet brain weight and protein content were significant for cerebellum but not for cerebrum. Animals undernourished in utero and fed normally after birth showed normal whole brain weight, cerebroside and sulfatide contents, and normal cerebrum cellularity by adulthood. However, the type of cells increasing in the cerebrum during postnatal rehabilitation is unknown. Wet weight and cellularity were still diminished by 22% and 17%, respectively, in the adult cerebella. The results suggest that adequate postnatal nutrition will offset some, though not all of the brain biochemical changes resulting from fetal undernutrition.
Singular solutions for a class of Grusin type operators

We construct singular solutions for a one-parameter family of partial differential equations with double characteristics and with complex lower order terms. The parameter belongs to a discrete set which is described in terms of the spectrum of a related differential operator.
From the brachystochrone to the maximum principle

Optimal control was born in 1696 in the Netherlands, when Johann Bernoulli challenged his contemporaries with the brachystochrone problem (BP). The purpose of this paper is to give a brief outline of why this event truly deserves to be called the birth of optimal control, and how the research that began in 1696 has led to modern optimal control theory and, especially, to the maximum principle. In particular, we argue that, as this path was followed, several opportunities were missed that would have led to much earlier discovery of the maximum principle. In at least one case-that of the formulation of Hamilton's equations-we attempt to show that the discovery was missed for no reason other than the decision to rewrite an equation in terms of one formalism rather than another one that would have been equally suitable and was also available at the time. As a conclusion, we show how a modern look at the BP, from the perspective of optimal control theory, can still yield new insights into this problem.
Logic in access control

Access control is central to security in computer systems. Over the years, there have been many efforts to explain and improve access control, sometimes with logical ideas and tools. This paper is a partial survey and discussion of the role of logic in access control. It considers logical foundations for access control and their applications, in particular in languages for programming security policies.
Intrachromosomal Recombination in Saccharomyces cerevisiae : Reciprocal Exchange in an Inverted Repeat and Associated Gene Conversion

Intrachromosomal gene conversion has not shown a strong association with reciprocal exchanges. However, reciprocal exchanges do occur between intrachromosomal repeats. To understand the relationship between reciprocal exchange and gene conversion in repeated sequences the recombination behavior of an inverted repeat was studied. We have found that in one orientation a single copy of the kanr gene of the bacterial transposon Tn903 flanked by part of the inverted repeats IS903 does not give G418 resistance in Saccharomyces cerevisiae. A reciprocal exchange in the IS903 repeats inverts the kan r gene, which then gives G418 resistance in a single copy. Using this as a selection for intrachromosomal reciprocal exchange we have introduced multiple restriction site heterologies into the IS903 repeats and examined the crossover products for associated gene conversions. Approximately 50% of crossovers, both in mitosis and meiosis, were associated with a gene conversion. This suggests that these crossovers result from an intermediate that gives a gene conversion in 50% of the events, that is, both reciprocal exchange and gene conversion between repeated sequences have a common origin. The data are most consistent with a heteroduplex mismatch repair mechanism.
Nanotechnology: Ethics and Society

From manufacturing to medicine, nanotechnology implies revolutionary change. However, the sweeping changes wrought by a technological advance of this magnitude are likely to come at a price that includes unforeseen environmental impact, disruptions in industry, displacement of workers, and deeply controversial applications of the technology and its offspring. Nanotechnology: Ethics and Society provides a conceptually clear and straightforward ethical framework, in which pragmatic questions can be raised regarding the impact of nano-related technologies. The book focuses on general issues related to nanotechnology in nanomaterials and manufacturing as well as impacts on the marketplace and workforce. After an overview of the nanotechnology revolution, the text illustrates key concepts in the assessment model and then applies this model to a case study related to human enhancement technologies. It also offers an ethical agenda for addressing the challenges of nanotechnology. Nanotechnology promises to be the next great technological revolution. This important volume provides a framework for deciding how best to take advantage of nanotechnology opportunities while also minimizing the harm of negative effects.
Henry Johnstone, Jr.'s Still-Unacknowledged Contributions to Contemporary Argumentation Theory

Given the pragmatic tum recently taken by argumentation studies, we owe renewed attention to Henry Johnstone's views on the primacy of process over product. In particular, Johnstone's decidedly non-cooperative model is a refreshing alternative to the current dialogic theories of arguing, one which opens the way for specifically rhetorical lines of inquiry.
Nonexistence of Small Amplitude Breather Solutions in $\phi^4$ Theory

For the (1+1)-dimensional Klein-Gordon equation called the phi/sup 4/ model, there is a known asymptotic series formally representing a ''breather'' (a real-valued solution that is localized in space and periodic in time) in the limit of small amplitude and frequency just below that of spatially uniform infinitesimal oscillations. We show that even though this expansion is valid to all orders, phi/sup 4/ theory admits no true breathers in this limit. Instead, what appear in many physical contexts are approximate breathers that slowly radiate their energy to x- +- infinity. We calculate this radiation rate, which lies beyond all orders in the asymptotic expansion.
Toxicological Considerations in Evaluating Indoor Air Quality and Human Health: Impact of New Carpet Emissions

This review article considers evidence regarding the toxicological impact of new carpet emissions on indoor air quality and human health. It compares emissions data from several studies and describes the dominant compounds found in those emissions. The toxicity of each these compounds is assessed for animal and human data, with a focus on inhalation exposure. Data for acute and chronic exposures are presented, and synergistic effects are considered. Differences and similarities between health responses caused by toxicity and/or by immunological reactions are discussed. Possible neurogenic pathways and associations between these and immune changes are considered as they might relate to inflammatory-based human reactions. Additionally, factors affecting human odor responses are described. The roles that a variety of psychological factors may also play in the etiology of potentially related phenomena, such as the sick building syndrome, pathogenic illness, and multiple chemical sensitivity, are considered. Gaps in the literature are identified within the article and suggestions for future research are offered. In particular, it is noted that few, if any, prior studies have evaluated both neurogenic and immune-mediated inflammation status within the same study. Based on the present information available, it is concluded that under normal environmental circumstances, VOC emissions from new carpets are sufficiently low such that they should not adversely affect indoor air quality or pose significant health risk to people.
Adaptation of a small-molecule hydrogen-bond donor catalyst to an enantioselective hetero-Diels-Alder reaction hypothesized for brevianamide biosynthesis.

Chiral diamine-derived hydrogen-bond donors were evaluated for their ability to effect stereocontrol in an intramolecular hetero-Diels–Alder (HDA) reaction hypothesized in the biosynthesis of brevianamides A and B. Collectively, these results provide proof of principle that small-molecule hydrogen-bond catalysis, if even based on a hypothetical biosynthesis construct, holds significant potential within enantioselective natural product synthesis.
A taxonomy for computer-based assessment of problem solving

Abstract Computer-based assessment of problem solving is motivated by the need for educational assessments that are valid and efficient. Based on a recent revision of Bloom's taxonomy (Anderson et al., 2001, A taxonomy for learning, teaching, and assessing: a revision of Bloom's taxonomy of educational objectives. New York: Longman), assessment items should require applying a particular cognitive process to a particular type of knowledge. There are 19 types of cognitive processes that can be classified into six major categories: remember, understand, apply, analyze, evaluate, and create. There are four major categories of knowledge: factual, conceptual, procedural, and metacognitive. Examples of computer-based assessments of problem-solving are provided based on the evaluation of the cognitive consequences of children's participation in an after-school computer club.
Stress fracture of the clavicle after a radical neck dissection; Case report.

Abstract We report a case of a stress fracture occurring in the medial end of the clavicle, 15 months after a radical neck dissection.
Interplanetary magnetic field enhancements: Evidence for solar wind dust trail interactions

Magnetic disturbances related to the passage of the asteroid 2201 Oljato are described. It is pointed out that the process leading to these disturbances must be associated with material in the orbit of Oljato and not the Oljato asteroid itself. Using data from latest space observations, the statistical association of these disturbances with the orbit of 2201 Oljato is updated, and the possible mechanisms for causing the disturbances are discussed. The phenomenon is considered to be associated with comet-like processes in the solar wind.
Carnap, Gödel, and the Analyticity of Arithmetic

Michael Friedman maintains that Carnap did not fully appreciate the impact of Godel's first incompleteness theorem on the prospect for a purely syntactic definition of analyticity that would render arithmetic analytically true. This paper argues against this claim. It also challenges a common presumption on the part of defenders of Carnap, in their diagnosis of the force of Godel's own critique of Carnap in his Gibbs Lecture.
Removal of the financial barrier to health care: Does it impact on prostate cancer at presentation and survival? A comparative study between black and white men in a Veterans Affairs system

Abstract Objectives African-American men are known to have a higher incidence and mortality rate from prostate cancer than American-Caucasian men. It is also known that African Americans have a higher incidence of advanced stage disease at diagnosis. One hypothesis for the latter is a delay in diagnosis due to lack of financial access to health care. Because eligibility for medical care in Veterans Affairs Medical Centers (VAMCs) is similar for both black and white patients, less disparity of stage at diagnosis, and therefore survival between blacks and whites, would be expected. Methods Cases for this study included only those histologically confirmed, newly diagnosed prostate cancers at the Allen Park VAMC in Wayne County, Michigan, between 1973 and 1992. Trained Surveillance, Epidemiology, and End Result (SEER) abstractors determined the stage at diagnosis, according to SEER criteria. Data analyses include descriptive statistics and survival analysis. Results The distribution of race and annual income of all male patients seen at the VAMC in Allen Park is similar. Over the entire 20-year period (1973 to 1992), there were a total of 358 prostate cancers in white patients and 383 in black patients. The ages of black and white patients were comparable. The proportion of white and black men presenting with localized disease is similar (57% and 54%, respectively). A significantly greater proportion of black patients with prostate cancer were classified as having distant disease compared with white patients (25% versus 19%; P = 0.045). A racial “crossover” effect in survival occurred around age 70 years, with white men demonstrating improved survival under 70 years of age, and black men 70 years and older tending to have better survival. Conclusions These data suggest that financial access to care has no apparent influence on the higher proportion of distant disease and poorer survival of African-American patients with prostate cancer compared with American-Caucasian men.
Effects and mechanisms of wakefulness on local cortical networks.

Summary Mammalian brains generate internal activity independent of environmental stimuli. Internally generated states may bring about distinct cortical processing modes. To investigate how brain state impacts cortical circuitry, we recorded intracellularly from the same neurons, under anesthesia and subsequent wakefulness, in rat barrel cortex. In every cell examined throughout layers 2–6, wakefulness produced a temporal pattern of synaptic inputs differing markedly from those under anesthesia. Recurring periods of synaptic quiescence, prominent under anesthesia, were abolished by wakefulness, which produced instead a persistently depolarized state. This switch in dynamics was unaffected by elimination of afferent synaptic input from thalamus, suggesting that arousal alters cortical dynamics by neuromodulators acting directly on cortex. Indeed, blockade of noradrenergic, but not cholinergic, pathways induced synaptic quiescence during wakefulness. We conclude that global brain states can switch local recurrent networks into different regimes via direct neuromodulation.
Association of 3.0-T brain magnetic resonance imaging biomarkers with cognitive function in the Dallas Heart Study.

Importance Understanding the relationships between age-related changes in brain structure and cognitive function has been limited by inconsistent methods for assessing brain imaging, small sample sizes, and racially/ethnically homogeneous cohorts with biased selection based on risk factors. These limitations have prevented the generalizability of results from brain morphology studies. Objective To determine the association of 3.0-T structural brain magnetic resonance (MR) imaging measurements with cognitive function in the multiracial/multiethnic, population-based Dallas Heart Study. Design, Setting, and Participants Whole-brain, 2-dimensional, fluid-attenuated inversion recovery and 3-dimensional, magnetization-prepared, rapid acquisition with gradient echo MR imaging at 3.0 T was performed in 1645 Dallas Heart Study participants (mean [SD] age, 49.9 [10.5] years; age range, 19-85 years) who received both brain MR imaging and cognitive screening with the Montreal Cognitive Assessment between September 18, 2007, and December 28, 2009. Measurements were obtained for white matter hyperintensity volume, total brain volume, gray matter volume, white matter volume, cerebrospinal fluid volume, and hippocampal volume. Linear regression and a best predictive model were developed to determine the association of MR imaging biomarkers with the Montreal Cognitive Assessment total score and domain-specific questions. Main Outcomes and Measures High-resolution anatomical MR imaging was used to quantify brain volumes. Scores on the screening Montreal Cognitive Assessment were used for cognitive assessment in participants. Results After adjustment for demographic variables, total brain volume ( P P P = .008, SE = .0687), cerebrospinal fluid volume ( P = .012, SE = −.0667), and hippocampal volume ( P P P = .01, SE = .0024), and hippocampal volume ( P = .004, SE = .1017) as 3 brain MR imaging biomarkers significantly associated with the Montreal Cognitive Assessment total score. Questions specific to the visuospatial domain were associated with the most brain MR imaging biomarkers (total brain volume, gray matter volume, white matter volume, cerebrospinal fluid volume, and hippocampal volume), while questions specific to the orientation domain were associated with the least brain MR imaging biomarkers (only hippocampal volume). Conclusions and Relevance Brain MR imaging volumes, including total brain volume, gray matter volume, cerebrospinal fluid volume, and hippocampal volume, were independently associated with cognitive function and may be important early biomarkers of risk for cognitive insult in a young multiracial/multiethnic population. A best predictive model indicated that a combination of multiple neuroimaging biomarkers may be more effective than a single brain MR imaging volume measurement.
The Effect of General Anesthesia on Radiofrequency Catheter Ablation for Supraventricular Tachycardia in Children

The Effect of General Anesthesia on Radiofrequency Catheter Ablation for Supraventricular Tachycardia in Children
Fine-Needle Aspiration Biopsy of Thyroid Nodules: Advantages, Limitations, and Effect

Background The efficacy of fine-needle aspiration (FNA) biopsy and its role in the management of a nodular goiter are clearly established. The accuracy of cytologic diagnosis approaches 95%. Findings FNA biopsy is a reasonable approach to thyroid nodules; it has decreased costs substantially because it facilitates selection of patients who need to undergo surgical excision. Selecting patients for operation on the basis of results of FNA biopsy has more than doubled the yield of carcinoma. The limitations of cytologic examination, nondiagnostic results, and cellular follicular neoplasms should be remembered but need not negate continued use of FNA biopsy. Negative (benign) and positive (malignant) cytologic results are conclusive; careful clinical follow-up of benign nodules and surgical excision of malignant nodules are recommended. Nondiagnostic results are inconclusive; further evaluation by repeated FNA biopsy, ultrasound-guided biopsy, or radionuclide scanning is necessary. Suspicious cytologic results are also inconclusive and are associated with a 20% chance of malignant involvement; surgical treatment is necessary for clarification. The role of levothyroxine therapy remains uncertain and is not recommended until compelling data are available. Conclusion FNA biopsy is a safe, simple, reliable, and cost-effective means of detecting benign nodules. FNA biopsy, not thyroid scanning or ultrasonography, is the preferred initial diagnostic test in all patients with thyroid nodules.
Prediction of calcium supplement use among college students: Application of the theory of reasoned action

Abstract As part of a survey on vitamin and mineral food supplement use at Pima Community College (Tucson, AZ), 247 students were exposed to a pamphlet emphasizing the need for calcium throughout life. The Theory of Reasoned Action was then used as a model to predict intention to consume supplemental calcium. Attitudes were found to be significant predictors of behavioral intention. Normative influences (family, friends and physicians) were much less strong. The beliefs most predictive of attitude were that calcium would improve disease resistance and that it provided good value for the money. Other beliefs of importance to the students were that calcium's use was scientifically based and that it contributed to a good diet. Intention to take supplemental calcium was highly correlated with user status: food supplement users were significantly more likely than non-users to report intention to take calcium. The findings indicate the utility of theory-driven research in nutrition. Using a model such as the Theory of Reasoned Action, individual beliefs and normative influences can be identified for target populations, facilitating the development of more appropriate nutrition education materials.
THE LOCALIZATION OF BETA-FRUCTOFURANOSIDASE IN NEUROSPORA.

1. 1. The s-fructofuranosidase (s-d-fructofuranoside fructohydrolase, EC 3.2.1.26) of Neurospora conidia is fully accessible to substrate, to aniline (an inhibitor), and to H+, as judged by the similarity of the kinetic properties of the conidial enzyme to those of highly purified preparations. The conidial and mycelial forms of s-fructofuranosidase are rapidly and completely inactivated under conditions which do not impair the viability of conidia, and fail to destroy alkaline phosphatase, which has been inferred on other grounds to be intracellular. 2. 2. A limited fraction of the conidial s-fructofuranosidase is easily removed by washing. 3. 3. The bound conidial s-fructofuranosidase, but not the crude or purified soluble enzyme, is resistant to pepsin inactivation. 4. 4. The results favor the view that this enzyme is located between the cell wall and the cell membrane.
Interparticle Charge Transfer Mediated by π−π Stacking of Aromatic Moieties

Electronic conductivity of Langmuir−Blodgett monolayers of phenylethylthiolate-protected gold nanoparticles was examined in vacuo at different temperatures. It was found that the ensemble conductance exhibited a volcano-shaped dependence on the interparticle separation, which was ascribed to the mediation of interparticle charge transfer by the π−π stacking of the phenyl moieties from neighboring particles. Additionally, the ensemble conductance was found to increase with increasing particle core size, most probably due to enhanced interparticle electronic (dipolar) interactions. Temperature dependence of the conductivity profiles suggested a thermal activation mechanism for the interparticle charge transfer driven by electron hopping. Thermally induced core motion was suspected to account for the different degree of temperature dependence of the ensemble conductivity with particle core size. Such ligand-mediated charge transfer may be exploited for sensing and device applications.
Testing for elliptical symmetry in covariance-matrix-based analyses

Many normal-theory test procedures for covariance matrices remain valid outside the family of normal distributions if the matrix of fourth-order moments has structure similar to that of a normal distribution. In particular, for elliptical distributions this matrix of fourth-order moments is a scalar multiple of that for the normal, and for this reason many normal-theory statistics can be adjusted by a scalar multiple so as to retain their asymptotic distributional properties across elliptical distributions. For these analyses, a test for the validity of these scalar-adjusted normal-theory procedures can be viewed as a test on the structure of the matrix of fourth-order moments. In this paper, we develop a Wald statistic for conducting such a test.
Strain- and overlayer-induced in-plane magnetocrystalline anisotropy: First-principles determination for fcc (110) Co thin films

The in-plane interface magnetocrystalline anisotropy (MCA) of fcc Co (110), either as a free standing monolayer or as an overlayer on a Cu substrate, is investigated using the local density all-electron full-potential linearized augmented plane-wave method. We find an in-plane MCA which has the same order of magnitude as the perpendicular MCA, and which exhibits a significant twofold anisotropy. The results for free standing monolayers calculated with different lattice constants reveal that (i) the strength of the in-plane MCA is severely changed by the strain \char22{} introducing an 8% strain (relative to the Cu lattice constant) induces a five times larger in-plane MCA \char22{} and (ii) the change of band structure due to the strain plays an important role in determining the in-plane MCA. The strength of the in-plane MCA is found to be largely enhanced by the nonmagnetic Cu substrate while it is reduced by the structural relaxation. Interestingly, for all systems the in-plane easy axis is found to lie along $[1\ifmmode\bar\else\textasciimacron\fi{}10$], which is along the direction of the in-plane nearest neighbor atom.
A mutation in the Bordetella bronchiseptica bvgS gene results in reduced virulence and increased resistance to starvation, and identifies a new class of Bvg‐regulated antigens

The Bordetella BvgAS signal-transduction system has traditionally been viewed as mediating a transition between two distinct phenotypic phases: the Bvg+ phase, characterized by the expression of adhesins and toxins, and the Bvg-phase, characterized by motility in Bordetella bronchiseptica and by the expression of vrg loci in Bordetella pertussis. In B. bronchiseptica, the Bvg+ phase is necessary and sufficient for respiratory tract colonization whereas the Bvg phase is required for growth under nutrient-limiting conditions. This report describes the characterization of a mutant that is locked in a Bvg-intermediate (Bvg[i]) phase. The mutation conferring this phenotype, designated bvgS-I1, results in a threonine-to-methionine substitution near the primary site of phosphorylation in BvgS. Compared to its Bvg+-phase-locked parent, the Bvg(i) mutant displays increased resistance to nutrient limitation and reduced virulence. Molecular analyses indicate that the mutant has lost the ability to express a subset of Bvg+-phase factors and has gained the ability to express factors unique to the Bvg(i) phase. Although identified by mutation, this work indicates that the Bvg(i) phase is expressed by wild-type B. bronchiseptica in response to certain (semi-modulating) environmental conditions. The identification of Bvg(i)-specific antigens suggests the existence of a new class of Bvg-regulated genes. We hypothesize that BvgAS is capable of mediating the expression of a spectrum of phenotypic phases in response to the various environments encountered as Bordetella travels within and between mammalian hosts.
Structure and polygonization of bent zinc monocrystals

Abstract The geometry of bent zinc crystals is discussed. It is found that the slip planes in bent zinc crystals have the shape of involutes with the hexagonal axes of the lamellae parallel to tangents of the evolute. This concurs with other investigators' results for bent corundum-crystals and with theory. Evidence is presented to show that bent crystals, especially sharply bent ones, are not necessarily polygonized immediately after bending. They sometimes contain low-angle grain-boundaries which may or may not form during the bending process. The normal structure of a homogeneously bent zinc crystal is believed to consist of a network of meandering dislocation lines connecting short segments of dislocation walls. Quantitative data on the kinetics of polygonization in cylindrically bent zinc crystals are presented. Polygonization, in the absence of inhomogeneous stresses, does not occur below about 170°C in “chemicallypure” zinc and this temperature is raised somewhat by contamination with 0.1 at. % Cd. At a given temperature, the polygon angles increase in proportion to the logarithm of the time. The temperature dependence of the growth rate, dθ/dt, at constant angle, varies with temperature. If an Arrhenius equation is used to describe it at temperatures below 250°C, Q is ~60 kcal/mol and at temperatures from 250 to 325°C, Q is ~20 kcal/mol. The effect of several variables on the polygon growth rate were investigated: 1. 1. Stress after annealing: causes boundaries to coalesce. 2. 2. Twins: on compression side they markedly inhibit polygon growth. 3. 3. Bending temperature: variations from −196°C to 225°C had no marked effect. 4. 4. Surface condition: no effect as long as surface was macroscopically smooth. 5. 5. Intermittent versus continuous anneals: no effect. 6. 6. Skew bending: no effect for small amounts of skewness. 7. 7. Radius of curvature: polygon size is roughly inversely proportional to radius of curvature at constant time and temperature. The theory of polygonization is discussed and it is pointed out that the rate of climb of unit dislocations does not seem to be the only factor that controls the growth rate.