cssi/SciSciGPT-SciSciNet huggingface dataset:
Arboreal ant community of a pine forest in northern Florida.

The arboreal ant fauna of the longleaf and slash pine forests of the Apalachicola National Forest in northern Florida was studied using baits placed on trunks 1 m above ground level. Crematogaster ashmeadi Mayr was by far the most abundant ant attracted to the baits, occurring on ≈50% of all the trees. In addition to C. ashmeadi, another 10 species of ants, both ground-nesting and arboreal-nesting, were commonly captured. There was a strong relationship between the identity and abundance of species of ants on pines and the mean tree diameter, indicating that the ant fauna changed as trees grew. In young, recently regenerated stands, baits attracted mostly ground-nesting species of ants. Newly mated C. ashmeadi queens colonize the dead branches of pine saplings. As tree size increased, tree occupancy by C. ashmeadi rose to a maximum of 60% in middle-sized trees and fell to 50% in the largest trees. Parallel to these changes, the proportion of trees occupied by ground-nesting ants fell from 33% in the smallest pines to ≈15% in the largest, whereas those occupied by arboreal ants other than C. ashmeadi rose from 2 to 25%. The data suggested that C. ashmeadi is a dominant ant species with which other species do not easily coexist. Coexistence of arboreal ants increased with tree size such that the proportion of trees with <1 species increased steadily from ≈4% in the smallest pines to ≈19% in the largest. The total number of species was about the same in small, medium, and large trees, but the identity of these species changed. As in other ant communities, the assembly of the arboreal ant community in this pine forest is probably an example of the nested-subset phenomenon. That is, the occurrence of species is determined by their ability to coexist with the dominant, aggressive, large-colonied species, in this case, C. ashmeadi.
Regulation and functional impact of lipopolysaccharide induced Nod2 gene expression in the murine epididymal epithelial cell line PC1

Epididymitis represents a serious threat to male fertility and usually develops following secondary bacterial infection of the epididymis such as urinary tract infections or sexually transmitted diseases. Surprisingly, very little is known about the innate host response triggered by bacterial infection in the male reproductive tract. In this study we investigated the regulation and function of Nod2 in epididymal epithelial cells following lipopolysaccharide (LPS) stimulation. The immortalized epididymal epithelial cell line PC1 (proximal caput 1) constitutively expressed Toll-like receptor 4, MD-2, CD-14 but not Nod2 messenger RNA. Lipopolysaccharide (LPS; 0.5 microg/ml) rapidly induced I kappaB phosphorylation and degradation, RelA nuclear translocation and phosphorylation, which correlated with enhanced transcriptional activity (four-fold) in PC1 cells. The LPS and lipid A rapidly (1 hr) induced Nod2 messenger RNA accumulation in a dose-dependent manner. RelA and RNApolII recruitment to the Nod2 gene promoter was enhanced in LPS-stimulated cells. Molecular blockade of nuclear factor-kappaB signalling with adenovirus 5 (Ad5) I kappaB AA or adenovirus 5 double-negative (Ad5dn) IKK beta prevented LPS-induced Nod2 gene expression. Functionally, Nod2 upregulation enhanced muramyl dipeptide (MDP) -induced tumour necrosis factor messenger RNA accumulation in PC1 cells. We conclude that epididymal epithelial cells mount an innate response following LPS exposure which leads to upregulation of Nod2 and enhanced responsiveness to the microbial product MDP. The rapid Nod2 upregulation in epididymal epithelial cells is probably part of a complex innate host response aimed at protecting the male reproductive tract from the deleterious impact of bacteria.
Panbiogeography, its critics, and the case of the ratite birds

Panbiogeographic analysis is now used by many authors, but it has been criticised in recent reviews, with some critics even suggesting that studies using the method should not be accepted for publication. The critics have argued that panbiogeography is creationist, that it rejects dispersal, that its analyses are disingenuous, and that it deliberately ignores or misrepresents key evidence. These claims are examined here, and are all shown to be without foundation. The distributions of the molecular clades of ratites have not been mapped before, and they are considered here in some more detail as a case study illustrating panbiogeographic methodology.
Prevalence of molecular markers for Salmonella and Shiga toxigenic Escherichia coli (STEC) in whole-muscle beef cuts sold at retail markets in Costa Rica

The present study sought to determine the prevalence of molecular markers for Salmonella and Shiga toxigenic Escherichia coli (STEC) serogroups O26, O45, O103, O111, O121, O145, and O157 in whole-muscle beef cuts sold at retail in urban and semi-rural areas of Costa Rica. A total of 279 (171 urban, 108 semi-rural) samples were purchased from 93 butcher shops between August of 2012 and August of 2013 and tested for the presence of molecular markers characteristic of Salmonella and STEC using the DuPont Qualicon BAX® System. The overall prevalence of Salmonella and STEC markers was 3.6% (10/279) and 4.7% (13/279), respectively. Salmonella markers were more frequently found in semi-rural (6.5%; 7/108) than in urban (1.8%; 3/171) areas. Similarly, STEC markers were more commonly detected in semi-rural (7.4%; 8/108) than in urban (2.9%; 5/171) areas. A marginal association was found between Salmonella markers and sampling location (P = 0.0496), whereas the presence of STEC markers and sampling location were considered independent (P = 0.1416). Among the 13 positive samples for STEC, 38 O-antigen gene fragments were amplified, with serogroups O45 and O121 being the predominant (28.9 and 21.1%, respectively). Markers for somatic antigens O111 and O157 were not detected in any of the samples. The present investigation is the first of its kind in Central America and shows that both Salmonella and STEC may be commonly present in whole-muscle raw beef cuts sold at retail markets in Costa Rica. Consequently, consumers may be directly at risk of foodborne illness due if meat products are not adequately cooked and handled in food service or domestic settings. Future work should emphasize continuous monitoring of the presence of these and other zoonotic pathogens in meat and meat products and on the implementation and validation of adequate food safety controls along the farm-to-table continuum.
The Performance of Performance-Based Budgeting in Boom Versus Bust Years: An Analytical Framework and Survey of States

This article divides the era of performance-based budgeting (PBB) into three periods: rise and development in the 1990s, continuation and peak in the 2000s and level-off afterwards. The article examines the performance of PBB on four aspects: development of performance measures, its use in budgeting and management, its utility across the business cycle, and its usefulness for budget players. We devise an analytical framework that builds on publicness as the distinctive feature of government, draws on the principal-agent model to emphasize issues of accountability, and brings in incentive mechanisms theory to show difficulty in performance measurement. We survey 11 representative states and find: that developing performance measures is a gradual process, that PBB functions better in management than in budgeting, that PBB is used widely in boom years but not in bust years, and that PBB is used selectively by legislators but more widely by the executives.
Conquest: How Societies Overwhelm Others – By David Day

This volume has a simple and seductive theme: that the history of the world can best be understood as “the history of peoples on the move, as they occupy new lands and establish their particular cl...
Chemotherapeutic Approaches for Targeting Cell Death Pathways

For several decades, apoptosis has taken center stage as the principal mechanism of programmed cell death in mammalian tissues. It also has been increasingly noted that conventional chemotherapeutic agents not only elicit apoptosis but other forms of nonapoptotic death such as necrosis, autophagy, mitotic catastrophe, and senescence. This review presents background on the signaling pathways involved in the different cell death outcomes. A re-examination of what we know about chemotherapy-induced death is vitally important in light of new understanding of nonapoptotic cell death signaling pathways. If we can precisely activate or inhibit molecules that mediate the diversity of cell death outcomes, perhaps we can succeed in more effective and less toxic chemotherapeutic regimens.
Convergent Evolution of Disease Resistance Gene Specificity in Two Flowering Plant Families

Plant disease resistance (R) genes that mediate recognition of the same pathogen determinant sometimes can be found in distantly related plant families. This observation implies that some R gene alleles may have been conserved throughout the diversification of land plants. To address this question, we have compared R genes from Glycine max (soybean), Rpg1-b, and Arabidopsis thaliana, RPM1, that mediate recognition of the same type III effector protein from Pseudomonas syringae, AvrB. RPM1 has been cloned previously, and here, we describe the isolation of Rpg1-b. Although RPM1 and Rpg1-b both belong to the coiled-coil nucleotide binding site (NBS) Leu-rich repeat (LRR) class of R genes, they share only limited sequence similarity outside the conserved domains characteristic of this class. Phylogenetic analyses of A. thaliana and legume NBS-LRR sequences demonstrate that Rpg1-b and RPM1 are not orthologous. We conclude that convergent evolution, rather than the conservation of an ancient specificity, is responsible for the generation of these AvrB-specific genes.
Diagnosis and management of congenital right pulmonary venous atresia.

Congenital unilateral pulmonary venous atresia is a rare anatomical defect. Patients present with pulmonary symptoms, and diagnosis may be ellusive. Pulmonary arterial wedge angiography is the gold standard with which to achieve diagnosis, and surgical intervention is often required for symptomatic patients.
Topography of the ISW2-nucleosome complex: insights into nucleosome spacing and chromatin remodeling.

Linker DNA was found to be critical for the specific docking of ISW2 with nucleosomes as shown by mapping the physical contacts of ISW2 with nucleosomes at base-pair resolution. Hydroxyl radical footprinting revealed that ISW2 not only extensively interacts with the linker DNA, but also approaches the nucleosome from the side perpendicular to the axis of the DNA superhelix and contacts two disparate sites on the nucleosomal DNA from opposite sides of the superhelix. The topography of the ISW2–nucleosome was further delineated by finding which of the ISW2 subunits are proximal to specific sites within the linker and nucleosomal DNA regions by site-directed DNA photoaffinity labeling. Although ISW2 was shown to contact ∼63 bp of linker DNA, a minimum of 20 bp of linker DNA was required for stable binding of ISW2 to nucleosomes. The remaining ∼43 bp of flanking linker DNA promoted more efficient binding under competitive binding conditions and was functionally important for enhanced sliding of nucleosomes when ISW2 was significantly limiting.
GENDER AND SPATIAL EDUCATIONAL ATTAINMENT GAPS IN TURKEY

This paper aims to investigate differences and similarities between and among the seven regions as well as the developed and the less developed provinces in Turkey for their gender gaps in educational attainment of the labor force. The study uses analysis of variance techniques to test equality of means between the regions and the provinces for the census period 1970 to 2000. The purpose is to determine whether gender gaps narrowed or expanded. The statistical tests rejected equality of the means for the six census periods for the seven regions and for the provinces. Multiple comparison procedures showed that changes in the means needed about a decade to materialize.
System-Level Types for Component-Based Design

We present a framework to extend the concept of type systems in programming languages to capture the dynamic interaction in component-based design, such as the communication protocols between components. In our system, the interaction types and the dynamic behavior of components are defined using interface automata - an automata-based formalism. Type checking, which checks the compatibility of a component with a certain interaction type, is conducted through automata composition. Our type system is polymorphic in that a component may be compatible with more than one interaction type. We show that a subtyping relation exists among various interaction types and this relation can be described using a partial order. This system-level type order can be used to facilitate the design of polymorphic components and simplify type checking. In addition to static type checking, we also propose to extend the use of interface automata to the on-line reflection of component states and to run-time type checking. We illustrate our framework using a component-based design environment, Ptolemy II, and discuss the trade-offs in the design of system-level type systems.
Personality and Political Attitudes: Relationships across Issue Domains and Political Contexts

Previous research on personality traits and political attitudes has largely focused on the direct relationships between traits and ideological self-placement. There are theoretical reasons, however, to suspect that the relationships between personality traits and political attitudes (1) vary across issue domains and (2) depend on contextual factors that affect the meaning of political stimuli. In this study, we provide an explicit theoretical framework for formulating hypotheses about these differential effects. We then leverage the power of an unusually large national survey of registered voters to examine how the relationships between Big Five personality traits and political attitudes differ across issue domains and social contexts (as defined by racial groups). We confirm some important previous findings regarding personality and political ideology, find clear evidence that Big Five traits affect economic and social attitudes differently, show that the effect of Big Five traits is often as large as that of education or income in predicting ideology, and demonstrate that the relationships between Big Five traits and ideology vary substantially between white and black respondents.
Using a pocket-filling strategy for distributed reconfiguration of a system of hexagonal metamorphic robots in an obstacle-cluttered environment

We address the problem of reconfiguration planning for a metamorphic robotic system composed of a large number of hexagonal mobile robots. Our objective is to develop an algorithm to plan the concurrent movement of individual robots over a lattice composed of identical robots, from an initial configuration I to a goal configuration G, when G contains one or more obstacles. The contribution of this paper is a deterministic motion planning algorithm to envelop multiple obstacles in an admissible set of goal configurations while eliminating the risk of module collision or deadlock. We developed a discrete event simulator to test our algorithms, and every admissible G tested was filled successfully. We include a full proof of correctness and analysis of our algorithm.
Listening to Loan Officers: The Impact of Commercial Credit Standards on Lending and Output

Over most of the last thirty-three years, the Federal Reserve has polled a small number of bank loan officers about their moves to tighten or ease commercial credit standards. Although the Senior Loan Officer Opinion Survey uses a small sample and gathers only qualitative information, it proves to be a useful tool in predicting changes in commercial lending and output. The authors find a strong correlation between tighter credit standards and slower loan growth and output, even after controlling for credit demand and other predictors of lending and output. The analysis also shows that the loan officer reports can help predict narrower measures of business activity, including inventory investment and industrial production.
Communion and Consent: Pierre Manent on the Wellsprings of Western Liberty

Abstract This article explores the intellectual itinerary of the contemporary French political philosopher Pierre Manent. In particular, it highlights his efforts to do justice to the three great “poles” of human existence: philosophy, politics, and religion. Manent is shown to be a philosophically minded Christian, one who thinks politically and who rejects the temptation to “despise the temporal order.” Manent's reservations about the European project in its present form are shown to be rooted in a understanding of politics that emphasizes the need to weave together “communion” and “consent” if Europeans are to avoid administrative despotism and those postpolitical fantasies that prevent them from thinking and acting politically. The article ends with a reflection on Manent's impressive history of “political forms” in the Western world.
Making Leave Easier: Better Compensation and Daddy-Only Entitlements

In 2006, Quebec enacted a landmark reform to paid parental leave that greatly improved the generosity of entitlements and established a father’s non-transferable right to paid leave. Using data from the Employment Insurance Coverage Survey and employing a dierence-in-dier ences setup, I nd that the reform was associated with a striking rise in fathers’ participation: an increase of 52 percentage points in fathers’ participation rates and an increase in fathers’ leave duration by 3 weeks. Further, there is evidence of an intra-household ypaper eect via the labeling of leave as ‘daddy-only’, i.e., the allocation of leave within a household appears to be inuenced by the framing of legal rights even when they do not bind. The reform was associated with an increase of 11 percentage points in mothers’ participation rates, and the duration of the average maternity leave increased by over half a month under the new program. I nd no change in mothers’ exit rates from the labor market on average but do nd an increase in the probability of returning to the pre-birth employer if her husband took leave. The reform was also associated with a reduction in the average income loss experienced by households in the month following the birth.
Escorting children to school: Statistical analysis and applied Modeling approach

An important aspect of intrahousehold interactions-joint travel arrangements that arise when adult household members escort children to school-is investigated. Previously published research on intrahousehold interactions have focused mostly on time allocation or episode generation between individual and joint activities and have largely been limited to interactions between household heads. Insights into the less-explored aspect of intrahousehold interactions between adults and children in the household are provided. Children are explicitly considered active agents in the intrahousehold decision making, and the interaction itself takes the form of a joint travel arrangement rather than a shared activity. A statistical analysis indicates the importance of this segment of intrahousehold interactions in the overall system of household activity and travel. A choice model, which is formulated and estimated, relates the probability of various types of ridesharing and escorting to the person, household, and zonal...
Impaired cognitive function in patients with atherosclerotic carotid stenosis and correlation with ultrasound strain measurements

article i nfo Introduction: It has been postulated that up to 11 million "silent" strokes occur annually. While these patients are without classic neurologic deficits, they may exhibit cognitive decline. In this study, we examine the cog- nitive function of patients with carotid stenosis. Additionally, we evaluate a noninvasive measure of strain in pulsating carotid artery plaques to determine its ability to predict cognitive decline. Methods: We administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to 44 patients with carotid stenosis. All patients had stenosis meeting NASCET or ACAS criteria for endarter- ectomy, and were classified as symptomatic or asymptomatic as defined by these publications. Age-adjusted scores for each of the 5 RBANS domains (immediate memory, visuospatial ability, language, attention, and delayed memory) were compared between symptomatic and asymptomatic patients. Mean score for each of the 5 domains was then compared to all other domains, regardless of symptom status. From this cohort, 23 patients underwent assessment of carotid plaque strain by tracking displacements in ultrasound radiofrequency data to estimate axial and principal strains over the cardiac cycle. Results: Thirty symptomatic and 14 asymptomatic patients were studied. Visuospatial scores were significantly lower than any other domain regardless of symptoms (pb0.05 for all pairwise comparisons). No other domain score was significantly different from any other. In the language domain, asymptomatic patients scored signif- icantly higher than symptomatic patients (pb0.05. For all other domains, no difference was found. Asymptom- atic patients showed a relationship between plaque strain and immediate memory (r=�.61, p=ns). Left carotid disease was associated with poorer performance across multiple cognitive domains with increasing accumulated strain. This was not seen in right carotid disease. Conclusion: Patients with large carotid plaques (>70% stenosis) exhibit significant difficulties in mental status whether classically symptomatic or asymptomatic. While language deficits may be a non-specifi cm arker for stroke symptoms, visuospatial deficits are seen before classic symptoms, suggesting that carotid disease may become symptomatic earlier and more subtly than previously suspected. Abnormal strain distribution with pul- sation may be related to cognition.
Evaluation of serum feline pancreatic lipase immunoreactivity and helical computed tomography versus conventional testing for the diagnosis of feline pancreatitis.

Serum feline trypsinogen-like immunoreactivity (fTLI) concentrations and abdominal ultrasound have facilitated the noninvasive diagnosis of pancreatitis in cats, but low sensitivities (33% and 20‐35%, respectively) have been reported. A radioimmunoassay has been validated to measure feline pancreatic lipase immunoreactivity (fPLI), but the assay’s sensitivity and specificity have not been established. In human beings, the sensitivity of computed tomography (CT) is high (75‐90%), but in a study of 10 cats, only 2 had CT changes suggestive of pancreatitis. We prospectively evaluated these diagnostic tests in cats with and without pancreatitis. In all cats, serum was obtained for fTLI and fPLI concentrations, and pancreatic ultrasound images and biopsies were acquired. Serum fPLI concentrations (P, .0001) and ultrasound findings (P 5 .0073) were significantly different between healthy cats and cats with pancreatitis. Serum fTLI concentrations (P 5 .15) and CT measurements (P 5 .18) were not significantly different between the groups. The sensitivity of fTLI in cats with moderate to severe pancreatitis was 80%, and the specificity in healthy cats was 75%. Feline PLI concentrations were both sensitive in cats with moderate to severe pancreatitis (100%) and specific in the healthy cats (100%). Abdominal ultrasound was both sensitive in cats with moderate to severe pancreatitis (80%) and specific in healthy cats (88%). The high sensitivities of fPLI and abdominal ultrasound suggest that these tests should play an important role in the noninvasive diagnosis of feline pancreatitis. As suggested by a previous study, pancreatic CT is not a useful diagnostic
Copolymerization of 1,6‐anhydro‐ß‐D‐galactopyranose and 1,6‐anhydro‐ß‐D‐mannopyranose derivatives

1,6-Anhydro-2,3,4-tri-O-(p-methylbenzyl)-s-D-galactopyranose (TXGal,M1) has been copolymerized with 1,6-anhydro-2,3,4-tri-O-benzyl-s-D-mannopyranose (TBMan,M2), the products characterized by NMR, specific rotation, and viscosity, and the reactivity ratios calculated. The reactivity ratios r1 = 0.37 ± 0.15 and r2 = 38 ± 4 indicate that the anhydromannose derivative is about 100 times as reactive as that of anhydrogalactose. A comparison of glucose, mannose, and galactose copolymerizations suggests that the reactivity differences of the three propagating cations are comparatively small and the reactivity differences of the monomers large. This result is consistent with a mechanism proposed earlier. Methyl substitution on the aromatic rings of the p-xylyl groups inhibits the initiation process significantly relative to benzyl, but propagation only slightly.
Impact of micro-inverter reactive power support capability in high penetration residential PV networks

With the steadily increasing penetration of residential and small commercial photovoltaic (PV) generation, interest has grown in utilizing this renewable generation source to support the power distribution grid, as clusters of residential solar have the potential to be used to provide reactive power support to the grid for voltage and frequency regulation through system level control and communication with the grid operator. Solar electric systems can also be used to improve voltage profiles on distribution feeders and also to provide power factor correction at the meter in each home. In this paper the impact of grid support functions of micro-inverter on the distribution network is studied for high penetration residential PV.
Leukemic and Lymphoid Stem Cells

Cancer cell heterogeneity is a feature of nearly all cancers and can be related to three major influences: (1) genetic and epigenetic heterogeneity due to clonal evolution/collapse; (2) microenvironmental influences; and (3) the underlying tissue hierarchy from which the tumor arises. Ongoing studies in whole genome sequencing and of the bone marrow, splenic and lymph node microenvironments demonstrate their contributions to tumor heterogeneity. In this chapter we will focus on the role of the hematopoietic hierarchy in blood cancer cellular heterogeneity; one of the most studied systems in mouse and human. Observations that myeloid and lymphoid malignancies harbor rare relatively quiescent therapy resistant cell populations date back over 30 years. Early studies in chronic myelogenous leukemia were consistent with a disease origin in the hematopoietic stem cell and subsequent studies have confirmed these findings. The publication by Bonnet et al. in 1994 offered the first prospective assessment of human cancer stem cell populations and established acute myeloid leukemia (AML) as a model system. In the intervening years, new technologies have allowed a continued reassessment of cancer stem cell populations in AML, myelodysplastic syndromes, multiple myeloma and acute lymphoblastic leukemia. While these studies have confirmed the existence of the rare cells capable of recapitulating the malignancy on transplantation, they have also identified considerable inter- and intra-patient heterogeneity with conflicting results on the ability to identify potential cancer stem cells using surface antigen profiles alone. Novel xenotransplantation models, whole genome sequencing and other technologies offer the tools to further refine this model in hematologic malignancies and develop rational therapies to target leukemia stem cells.
The influence of phonotactic probability and neighborhood density on children's production of newly learned words.

ABSTRACTA word learning paradigm was used to teach children novel words that varied in phonotactic probability and neighborhood density. The effects of frequency and density on speech production were examined when phonetic forms were nonreferential (i.e., when no referent was attached) and when phonetic forms were referential (i.e., when a referent was attached through fast mapping). Two methods of analysis were included: kinematic variability of speech movement patterning and measures of segmental accuracy. Results showed that phonotactic frequency influenced the stability of movement patterning whereas neighborhood density influenced phoneme accuracy. Motor learning was observed in both nonreferential and referential novel words. Forms with low phonotactic probability and low neighborhood density showed a word learning effect when a referent was assigned during fast mapping. These results elaborate on and specify the nature of interactivity observed across lexical, phonological, and articulatory domains.
Mitochondria just wanna have FUN(DC1)

A fascinating story is unfolding at the interface between mitochondria and the ER. Two new papers, one in this issue of The EMBO Journal (Wu et al , [2016][1]) and one in the journal Autophagy (Chen et al , [2016][2]), further clarify the role of mitochondrial outer membrane protein FUNDC1 in autophagy and connect it to mitochondrial fission occurring at the interface between mitochondria and the ER. [1]: #ref-10 [2]: #ref-2
Islamophobia, Hateful Speech, and the Need to Practice Democratic Virtues

This essay examines the relationship between hateful speech and its potential and realized harmful effects socially and politically vulnerable groups, particularly Muslims, in a democratic society. I critically evaluate the assumption that free speech is an absolute value of secularism and the corresponding definition of Muslims as religious “others” in European and American democratic culture. Instead of arguing strictly for the legal regulation of hateful speech, however, I contend that the cultivation of civic virtues—specifically charity and solidarity—may counteract the harmful effects of such speech, and can lend moral justification for the right of free speech.
Echocardiography in stroke patients (with emphasis on cryptogenic stroke)

As discussed throughout this review, multiple potential cardioembolic sources for stroke can be identified with the use of echocardiography. We believe that echocardiography plays an important role in the evaluation and risk stratification of patients with suspected cardioembolic stroke and, when used appropriately, can help in the management and treatment of these patients. Although TTE is superior for evaluation for the presence of a mural thrombus, TEE offers a higher sensitivity and specificity in identifying nearly all other potential cardiac sources of stroke. In the patient in whom the clinical scenario appears to implicate the heart as a potential culprit in an embolic event, the threshold for evaluation with echocardiography should be low.
The smooth transition from field emission to a self-sustained plasma in microscale electrode gaps at atmospheric pressure

We report on the existence of a smooth transition from field emission to a self-sustained plasma in microscale electrode geometries at atmospheric pressure. This behavior, which is not found at macroscopic scales or low pressures, arises from the unique combination of large electric fields that are created in microscale dimensions to produce field-emitted electrons and the high pressures that lead to collisional ionization of the gas. Using a tip-to-plane electrode geometry, currents less than 10 μA are measured at onset voltages of ∼200 V for gaps less than 5 μm, and analysis of the current–voltage (I-V) relationship is found to follow Fowler–Nordheim behavior, confirming field emission. As the applied voltage is increased, gas breakdown occurs smoothly, initially resulting in the formation of a weak, partial-like glow and then a self-sustained glow discharge. Remarkably, this transition is essentially reversible, as no significant hysteresis is observed during forward and reverse voltage sweeps. In cont...
Axonal model for temperature stimulation

Recent studies indicate that a rapid increase in local temperature plays an important role in nerve stimulation by laser. To analyze the temperature effect, our study modified the classical HH axonal model by incorporating a membrane capacitance-temperature relationship. The modified model successfully simulated the generation and propagation of action potentials induced by a rapid increase in local temperature when the Curie temperature of membrane capacitance is below 40 °C, while the classical model failed to simulate the axonal excitation by temperature stimulation. The new model predicts that a rapid increase in local temperature produces a rapid increase in membrane capacitance, which causes an inward membrane current across the membrane capacitor strong enough to depolarize the membrane and generate an action potential. If the Curie temperature of membrane capacitance is 31 °C, a temperature increase of 6.6---11.2 °C within 0.1---2.6 ms is required for axonal excitation and the required increase is smaller for a faster increase. The model also predicts that: (1) the temperature increase could be smaller if the global axon temperature is higher; (2) axons of small diameter require a smaller temperature increase than axons of large diameter. Our study indicates that the axonal membrane capacitance-temperature relationship plays a critical role in inducing the transient membrane depolarization by a rapidly increasing temperature, while the effects of temperature on ion channel kinetics cannot induce depolarization. The axonal model developed in this study will be very useful for analyzing the axonal response to local heating induced by pulsed infrared laser.
The EPSPS Pro106Ser substitution solely accounts for glyphosate resistance in a goosegrass (Eleusine indica) population from Tennessee, United States

Abstract Previous studies have documented the occurrence of glyphosate-resistant (GR) goosegrass (Eleusine indica (L.) Gaertn.) and, in at least some cases, resistance is due to an altered target site. Research was performed to determine if an altered target site was responsible for GR in a Tennessee, United States goosegrass population (TennGR). DNA sequencing revealed a mutation in TennGR plants conferring the Pro106Ser 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) substitution previously identified in other GR populations. F2 populations were derived from TennGR plants crossed with plants from a glyphosate-susceptible population (TennGS) and analyzed for their response to glyphosate and genotyped at the EPSPS locus. Plants from the F2 populations segregated 1:2:1 sensitive:intermediate:resistant in response to a selective dose of glyphosate, and these responses co-segregated with the EPSPS genotypes (PP106, PS106, and SS106). To separately investigate the effect of the Pro106Ser substitution on GR, glyphosate dose-response curves and 50% effective dose (ED50) values were compared among the three genotypes and the two parental populations. The SS106 genotype was 3.4-fold resistant relative to the PP106 genotype, identical to the resistance level obtained when comparing the resistant and susceptible parental populations. We conclude that the mutation conferring a Pro106Ser EPSPS mutation is solely responsible for GR in the TennGR goosegrass population.
System Modeling in Space

The word “system” is interpreted in various ways by different people. To some of my colleagues in computer science and management information systems, the word implies computer systems, and a systems analyst usually means computer systems analyst. To the scholars in organizational psychology, the word is used for organizational systems. They argue that the study of business, social or any other organization needs an overall approach, meaning any change in one area is going to affect another area. In sociology, the use of a social system concept is well known through the development of Talcott Parsons’ theory [1961].
Temporal Lobe Malformations and Epilepsy

Temporal lobe developmental malformations (TLDM) (focal cortical dysplasia and balloon cells) occurred with mesial temporal sclerosis as dual pathologies in 87% of 30 patients with unilateral TLDM and intractable partial epilepsy treated at the UAB Epilepsy Center, University of Alabama at Birmingham, AL.
The crystal structure of carbamoyl fluoride, NH 2 COF

Although first synthesized in 1940, the X-ray crystal structure of carbamoyl fluoride, NH2COF, has until now remained unknown. [1] NH2COF crystallizes in the orthorhombic space group Ibam, is planar, and exhibits a short C-N bond length, 1.3168(13) A, implying a significant degree of donation from the nitrogen lone pair. The structure features one molecule in the asymmetric unit and eight molecules in the unit cell. There are four molecules in two planar layers that are connected by a network of NH·O hydrogen bonds with N·O distances of 2.987(2) A and 2.945(2) A. The compound was also studied by quantum chemical calculations at both the ab initio (MP2) and density functional theory (B3LYP) level.
Accessing alternative reaction pathways of the intermolecular condensation between homo-propargyl alcohols and terminal alkynes through divergent gold catalysis

An intermolecular condensation of alkynols and terminal alkynes is reported. Using IPrAuNTf2, an efficient Au-catalyzed cyclization-alkynylation strategy furnishes (2-arylalkynyl) cyclic ethers in moderate to excellent yields (up to 94%). This strategy is extended to the synthesis of functionalized 2,3-dihydrooxepines via the sequential Au-catalyzed ring expansion of the cyclic ether substrates.
Reconnecting Students to School: An Outdoor Approach

This article suggests that using the outdoors for school activities can be an effective way to build enthusiasm toward learning, address inactivity levels, and improve behavior among students, as well as build community relationships, which can strengthen school connectedness.
Effects of grazing tall fescue containing ergot alkaloids on bull sperm cryopreservation.

There are many positive agronomic traits that make tall fescue a desirable forage, however, reduced fertility rates are reported for beef cattle grazing pasture containing the ergot alkaloid-producing endophyte, Epichloe coenophiala. The objective of this study was to assess the influence of consuming tall fescue containing ergot alkaloids on sperm physiology, as measured by survival of sperm following cryopreservation. Yearling Angus bulls (n=25), having passed a breeding soundness exam (BSE), were assigned to one of two treatments accounting for body weight (BW) and body condition score (BCS). Bulls were allotted to one of two treatments on day (d) 0, grazing toxic Kentucky 31 (KY31) or a novel endophyte-containing cultivar, Texoma Max Q II (NE; AR584 Ag Research) that does not produce ergot alkaloids, for 112 days. On d 112, all bulls were placed on NE pasture to the end of test (d 168) to evaluate recovery from grazing KY31. Blood, urine, and semen samples were collected every 28 days. Semen collected on d 28, 84, 112, 140, and 168 was extended, frozen, thawed 48h later, and subjected to analyses. There were significant treatment by day interactions for serum prolactin (PRL) concentrations, verifying the effectiveness of treatment (P<0.05). Serum PRL concentrations were less in the bulls pastured on KY31 compared to NE on d 28, 84, and 112. Urinary alkaloid concentrations were affected by treatment by day interactions, confirming ergot alkaloids were present in animal systems (P<0.05). Bulls in the NE treatment group had lesser urinary alkaloid concentrations than those pastured on KY31 on d 28, 84, and 112. Post-thaw sperm analyses revealed that the percentage of progressively motile sperm was less in bulls pastured on KY31 when compared to NE (P<0.05). There were treatment by day interactions for sperm concentration, percent motile sperm, percent motile sperm concentration, and percent progressively motile sperm concentration post-thawing (P<0.05). The KY31 treatment group had a lesser sperm 1) concentration than the NE group on d 84; 2) percent motility on d 28, 84, and 168; 3) motile concentration on d 28, 84, and 168; and 4) progressively motile concentration on d 28 and 84. Sperm motility was affected post-thawing for at least 56 d following removal from the KY31 pasture.
nBioChip, a Lab-on-a-Chip Platform of Mono- and Polymicrobial Biofilms for High-Throughput Downstream Applications

ABSTRACT Current in vitro techniques for the culture of microorganisms, and particularly of delicate microbial biofilms, are still mostly limited to low-density plates and manual labor and are not amenable to automation and true high-throughput (HT) applications. We have developed a novel fully automated platform for the formation of mono- and polymicrobial biofilms of Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans at the nanoscale level. The nBioChip is robotically printed, robustly handled, and scanned using a standard microarray reader. Using this technique, hundreds to thousands of identical nanobiofilms encapsulated in hydrogel spots were cultured on microscope slides. The spots can withstand the washing steps involved in screening assays. The miniaturized biofilms demonstrated characteristics similar to those displayed by conventionally formed macroscopic biofilms, including (i) three-dimensional architectural features, (ii) synthesis of exopolymeric matrix material, and (iii) elevated resistance to antibiotic treatment. On the basis of our results, the nBioChip can generate reliable high-throughput antimicrobial susceptibility testing (HT-AST) in 12 to 18 h. The chip serves as a proof-of-concept universal platform for high-throughput drug screening and other downstream applications and furthers understanding of microbial interactions in mixed-species communities at the nanoscale level. IMPORTANCE With an estimated 80% of infections being associated with a biofilm mode of growth and the ensuing recalcitrance of these biofilms with respect to conventional antibiotic treatment leading to high mortality rates, there is a dire and unmet need for the development of novel approaches to prevent, treat, and control these infections. Both bacteria and fungi are capable of forming biofilms that are inherently fragile and often polymicrobial in nature, which further complicates treatment. In this work, we showcase a nanobiofilm chip as a convenient platform for culturing several hundreds of mono- or polymicrobial biofilms and for susceptibility testing. This platform enables true ultra-high-throughput screening for antimicrobial drug discovery or diagnostics or for addressing fundamental issues in microbiology.
The Effects of School Climate on Changes in Aggressive and Other Behaviors Related to Bullying.

The school setting is the primary context in which most childhood bullying and victimization by peers occurs (Olweus, 1978). Moreover, intervention efforts undertaken by investigators to reduce or prevent bullying typically are implemented in the schools (U.S. Departments of Education and Justice, 1999). Whether considered individually or on a system-wide level, schools also are the preferred unit of analysis chosen by researchers when reporting rates of bullying and victimization (e.g., Boulton & Underwood, 1992; Olweus, 1993; Whitney & Smith, 1993). In a recent survey of more than 15,000 students in grades 6 through 10 in the United States, 29.9% reported either bullying others or being victimized by others, or both, at least some of the time during the current school term (Nansel et al., 2001). Middle and high school students have reported rates as high as 75% for being victimized at least once during the course of their school years (Hoover, Oliver, & Hazler, 1992). Bjorkqvist and Osterman (1999) note that “bullying has probably occurred as long as there have been schools” (p. 57). There is clear evidence that schools do inﬂuence children’s intellectual,emotional, and behavioral development; yet, to date, information about school context inﬂuences on bullying is limited. This chapter will focus on qualities of the social and emotional climate of the school and how they may be implicated in the facilitation or deterrence of school bullying.
The “Long Wave” Approximation & Geostrophy

The quasigeostrophic approximation, so useful in the middle latitudes, is notoriously inaccurate near the equator. This chapter describes a replacement that has been extremely useful in low latitude dynamics. The “long wave” approximation, which might equally well be dubbed the “low frequency” or “meridional geostrophy” approximation, filters gravity waves while retaining Kelvin and Rossby waves. The key assumption is that there is geostrophic balance in the latitudinal momentum equation only. This chapter also discusses the separation between the high and low frequency waves and the usefulness of this separation for initialization of equatorial numerical models.
The Importance of Geographic and Biological Variables in Predicting the Naturalization of Non-Native Woody Plants in the Upper Midwest

The selection, introduction, and cultivation of non-native woody plants beyond their native ranges can have great benefits, but also unintended consequences. Among these consequences is the tendency for some species to naturalize and become invasive pests in new environments to which they were introduced. In lieu of lengthy and costly field trials, risk-assessment models can be used to predict the likelihood of naturalization. We compared the relative performance of five established risk-assessment models on species datasets from two previously untested areas: southern Minnesota and northern Missouri. Model classification rates ranged from 64.2 to 90.5%, biologically significant errors ranged from 4.4 to 9.3%, and horticulturally limiting errors ranged from 6.6 to 30.4%. For the random forest model, we investigated the importance of variables used to predict naturalization by examining datasets for five distinct study areas across the Upper Midwest. Geographic-risk ratios were the most important predictor...
What's New with Lactose Permease

The lactose permease ofEscherichia coli is a paradigm for polytopic membrane transport proteins that transduce free energy stored in an electrochemical ion gradient into work in the form of a concentration gradient. Although the permease consists of 12 hydrophobic transmembrane domains in probable α-helical conformation that traverse the membrane in zigzag fashion connected by hydrophilic “loops”, little information is available regarding the folded tertiary structure of the molecule. In a recent approach site-directed fluorescence labeling is being used to study proximity relationships in lactose permease. The experiments are based upon site-directed pyrene labeling of combinations of paired Cys replacements in a mutant devoid of Cys residues. Since pyrene exhibits excimer fluorescence if two molecules are within about 3.5A, the proximity between paired labeled residues can be determined. The results demonstrate that putative helices VIII and IX are close to helix X. Taken together with other findings indicating that helix VII is close to helices X and XI, the data lead to a model that describes the packing of helices VII to XI.
Current Status of the Research on III-V Mononitride Thin Films for Electronic and Optoelectronic Applications

Continued development and commercialization of optoelectronic devices, including light-emitting diodes and semiconductor lasers produced from III-V gallium arsenide-based materials, has also generated interest in the much wider bandgap semiconductor mononitride materials containing boron, aluminum, gallium and indium. The majority of the studies have been conducted on pure gallium nitride thin films having the wurtzite structure, and this emphasis continues to the present day. However, recent research has resulted in the fabrication of p-n junctions in cubic boron nitride, the deposition of cubic gallium nitride, as well as, the fabrication of multilayer heterostructures and the formation of thin film solid solutions. Chemical vapor deposition (CVD) has usually been the technique of choice for thin film fabrication. However, more recently these materials have also been deposited by plasma-assisted CVD, reactive ionized-cluster beam deposition, and reactive and ionized molecular beam epitaxy. The objective of this paper will be to review the recent developments in all the III-V nitride thin film materials vis' a' vis' electronic and optoelectronic applications.