cssi/SciSciGPT-SciSciNet huggingface dataset:
ScRNA-seq reveals tumor microenvironment remodeling induced by local intervention-based immunotherapy

ABSTRACT Laser immunotherapy (LIT) combines local photothermal therapy (PTT), to disrupt tumor homeostasis and release tumor antigens, and an intratumorally administered immunostimulant, N-dihydrogalactochitosan (GC), to induce antitumor immune responses. We performed single-cell RNA sequencing on tumor-infiltrating leukocytes of MMTV-PyMT mouse mammary tumors to characterize LIT-induced myeloid and lymphoid compartment remodeling. Analysis of 49,380 single cell transcriptomes from different treatment groups revealed that proinflammatory IFNα, IFNγ, and TNFα cytokine signaling pathways were enriched in both lymphoid and myeloid cells isolated from LIT-treated tumors. The CD4+ and CD8+ T cells in LIT treated tumors resided in an activated state while immune cells in untreated and PTT-treated tumors remained in a neutral/resting state. Additionally, monocytes recruited into the LIT-treated tumors were driven towards proinflammatory M1-like macrophage phenotypes or monocyte-derived dendritic cells. Our results reveal that LIT prompts immunological remodeling of the tumor microenvironment by initiating broad proinflammatory responses to drive antitumor immunity. STATEMENT OF SIGNIFICANCE Transcriptome profiling of tumor infiltrating leukocytes revealed that localized laser immunotherapy (LIT) greatly enhanced antitumor T cell activity by promoting proinflammatory myeloid cell responses within the tumor microenvironment. This manuscript demonstrates that LIT broadly stimulates antitumor immunity and has great potential to synergize with current immunotherapies to increase their efficacy.
Measuring Customer Similarity and Identifying Cross-Selling Products by Community Detection

Product affinity segmentation discovers groups of customers with similar purchase preferences for cross-selling opportunities to increase sales and customer loyalty. However, this concept can be ch...
The lasting footprint of COVID-19 on surgical education: A resident and attending perspective on the global pandemic.

Abstract Background The COVID-19 pandemic has impacted surgical training nationwide. Our former curricula will likely not return, and training will need to adapt, so we are able to graduate residents of the same caliber as prior to the pandemic. Methods A survey evaluating perceptions of changes made in surgical training was conducted on surgery residents and attendings. Results Disaster medicine training has become more relevant and 85% residents and 75% attendings agreed it should be incorporated into the curriculum. Safety of family was the most significant concern of residents. Virtual curriculum was perceived to be acceptable by 82% residents and only 22% attendings (p Conclusions To maintain an effective surgical curriculum, programs will need to implement new educational components to better prepare residents to become surgeons of the future.
Nasal and paranasal sinus mucosal melanoma: Long-term survival outcomes and prognostic factors.

Abstract Objective To determine prognostic factors and survival patterns for different treatment modalities for nasal cavity (NC) and paranasal sinus (PS) mucosal melanoma (MM). Methods Patients from 1973 to 2013 were analyzed using the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier method and multivariable cox proportional hazard modeling were used for survival analyses. Results Of 928 cases of mucosal melanoma (NC = 632, PS = 302), increasing age (Hazard Ratio [HR]:1.05/year, p Conclusion Surgery increased survival significantly over RT alone. RT following surgical resection did not improve survival.
Demographic Disparities in Proximity to Certified Stroke Care in the United States.

Background and purpose Demographic disparities in proximity to stroke care influence time to treatment and clinical outcome but remain understudied at the national level. This study quantifies the relationship between distance to the nearest certified stroke hospital and census-derived demographics. Methods This cross-sectional study included population data by census tract from the United States Census Bureau's 2014-2018 American Community Survey, stroke hospitals certified by a state or national body and providing intravenous thrombolysis, and geographic data from a public mapping service. Data were retrieved from March to November 2020. Quantile regression analysis was used to compare relationships between road distance to the nearest stroke center for each census tract and tract-level demographics of age, race, ethnicity, medical insurance status, median annual income, and population density. Results Two thousand three hundred eighty-eight stroke centers and 71 929 census tracts including 316 995 649 individuals were included. Forty-nine thousand nine hundred eighteen (69%) tracts were urban. Demographic disparities in proximity to certified stroke care were greater in nonurban areas than urban areas. Higher representation of individuals with age ≥65 years was associated with increased median distance to a certified stroke center in nonurban areas (0.51 km per 1% increase [99.9% CI, 0.42-0.59]) but not in urban areas (0.00 km [-0.01 to 0.01]). In urban and nonurban tracts, median distance was greater with higher representation of American Indian (urban: 0.10 km per 1% increase [0.06-0.14]; nonurban: 1.06 km [0.98-1.13]) or uninsured populations (0.02 km [0.00-0.03]; 0.27 km [0.15-0.38]). Each $10 000 increase in median income was associated with a decrease in median distance of 5.04 km [4.31-5.78] in nonurban tracts, and an increase of 0.17 km [0.10-0.23] in urban tracts. Conclusions Disparities were greater in nonurban areas than in urban areas. Nonurban census tracts with greater representation of elderly, American Indian, or uninsured people, or low median income were substantially more distant from certified stroke care.
Comparison of the Wrist-Worn Fitbit Charge 2 and the Waist-Worn Actigraph GTX3 for Measuring Steps Taken in Occupational Settings.

Objectives If consumer-based monitors such as Fitbit can measure activity accurately, it could provide opportunities for improved assessment of physical activity in general and at work for research purposes. The accuracy of the Fitbit has hardly been investigated in an occupational setting. Methods We compared measurements of steps taken at work, out-of-work, and in total of a wrist-worn Fitbit to a waist-worn Actigraph. Seventeen participants wore the Fitbit and Actigraph for 1 full workday. Results Compared with the Actigraph, the Fitbit consistently recorded more steps [mean steps at work Fitbit = 7850 (6974), Actigraph = 4396 (1991); out-of-work Fitbit = 6414 (5691), Actigraph = 4116 (3502); total Fitbit = 13 478 (10 666), Actigraph = 8009 (5167)]. Conclusions Compared with the Actigraph, the Fitbit consistently recorded more steps at work, out-of-work, and in total. The Fitbit and Actigraph recordings were more consistent for measuring steps taken out-of-work compared with at work. Steps counts recorded by the Fitbit, especially in occupational settings, may be inaccurate.
Building an American Soil Survey

Early soil maps in the USA were made by the state geological surveys. One of the first soil maps was made in Wisconsin in 1882, followed by soil maps of Mississippi, Maryland, and Tennessee. In 1891, a soils division was established within the Department of Agriculture. In 1899, it began a program that aimed for a nationwide soil survey similar to the geological survey. In this new survey program, the soils would be mapped, studied, and described in reports that were to be publicly distributed. An important purpose of the soil survey was to help settlers. The focus was agrarian as in the 1890s over 40% of the population were farmers. Soil observations were made in the field, and soils were then clustered into soil types, series, and provinces. Some theory was developed as to why certain soils were found in certain locations. The first field manual was published in 1903, and Milton Whitney was the first chief. He held a geological view on the survey, was successful in obtaining funds, but also had arguments with the leading soil researchers at the time including Eugene Hilgard, Franklin King, and Cyril Hopkins. He was succeeded by Curtis Marbut. In order to exchange experiences and to form a community, the American Association of Soil Survey Workers was established in 1920 that became the foundation for the Soil Science Society of America in 1936.
Causality condition for time domain analysis of pulse distortion in lossy dispersive interconnects

This paper presents the causality condition for the time domain analysis of the pulse distortion in interconnects on GaAs substrates due to dispersion and losses. The causality condition is utilized to derive the response function for the complex propagation constant. The transient response to the input pulse is obtained by solving a first-order partial-differential equation with the convoluted coefficient. The solution procedure is implemented in a recursive manner by using the exponential approximation. As an example, the results for a single microstrip interconnect are demonstrated.
Time-Temperature Simulation in Low-Pressure Ignition of Hypergolic Liquids

T work is concerned with the ignition of hypergolic liquids at various pressures, and attempts to simulate timetemperature relationships in a droplet before it bursts into flame. It is known ~ that the ignitibility of a propellant can be affected drastically by changes in pressure, as well as temperature and the geometry of the enclosure surrounding the impinging streams of reactants. But the reasons for this sensitivity are not clear, nor is it known whether liquid particles that differ in size also differ in ignition behavior. At atmospheric pressure, two liquids that comprise a hypergolic mixture burst into flame almost as soon as they meet. At lower pressure there is longer delay before ignition occurs. Then, below some pressure, ignition does not occur, even though slightly above this point the hypergolic mixture does ignite after a reasonable delay time. The pressure at which cut-off occurs, marking the boundary between ignition and nonignition, is not well defined and reproducibility becomes increasingly more difficult as the pressure is reduced.
Compressive sensing based contrast-enhanced thermoacoustic imaging for breast cancer detection

Thermoacoustic imaging (TAI) has been shown to be promising for breast cancer detection. Contrast-enhanced TAI (CETAI) applying exogenous contrast agents can enhance the contrast in the dielectric properties between the tumor and its surrounding tissues. Combining compressive sensing (CS) and CET AI can make the measurements much more time-efficient. This work proposes a new approach to enable the advancing of the CS based CETAI from 2-D to 3-D. Simulation result using a realistic breast phantom shows that the measurement of CS based CET AI can be expedited by a factor more than 10 compared with the conventional CET AI.
Train control for light rail systems on shared tracks

New Jersey Transit (NJT) will install a light rail system along the Delaware River connecting the cities of Camden and Trenton. Light rail vehicles (LRV) will share Conrail freight trackage through 85% of the 34 mile long route; this will be one of the few freight and light rail shared traffic lines in North America. The train control system for the Southern New Jersey Light Rail Transit System (SNJLRTS) will be used by both LRT and Conrail freight trains. Significant differences in operating characteristics of light rail vehicles and freight trains, such as maximum allowed speed, length and weight of the consist, and brake rate, constitute technical problems that require unique solutions to assure effective and safe traffic for both types of vehicles. The SNJLRTS will employ a relatively simple signaling system that includes three-aspect automatic block signaling and automatic trip stops at the signals with red aspects. Block signal design will be one of the major issues associated with mixed traffic. The rules for conventional block signal design will be only partially applicable for SNJLRTS. In order to comply with internal NJT practices and Federal Railroad Administration (FRA) rules, and at the same time fulfil contract specifications requirements, unique solutions must be found for certain block signal design elements. The logic of grade crossing warning functioning will be another critical issue for mixed traffic. This paper describes the technical solutions that reconcile the LRT and freight train operational differences while designing the SNJLRTS train control system.
Role of crystal cumulates and the oceanic crust in the formation of the lower crust of the Aleutian arc

The crust in the central oceanic Aleutian arc has been formed by intrusion and extrusion of subduction-related magmas into and onto pre-existing oceanic crust over at least the past 50 m.y. Upper crustal rocks that have differentiated from a parental magma of olivine tholeiite composition, and residual crystals complementary to them, along with the pre-existing oceanic crust and some early extrusive lavas, form the lower crust. The volumes of upper and lower crust calculated from crystal fractionation models are consistent with Aleutian crustal structure, velocity, and density. Xenoliths of ultramafic to intermediate composition igneous cumulate rocks and garnet-free basaltic pyroxene granulites in Aleutian volcanic rocks confirm the existence of the predicted rock types in lower crust. Residues complementary to the Fe-rich basalts from tholeiitic volcanoes that have differentiated at low pressure should form part of the upper to middle crust. The model implies that continental crust formed by the accretion of island-arc terrains, which comprise most new Phanerozoic crust, has a basaltic lower crust.
Two ge neral classes of search designs for factor screening experiments with factors at three levels

In this paper, we are presenting general classes of factor screening designs for identifying a few important factors from a list of m (≥ 3) factors each at three levels. A design is a subset of 3m possible runs. The problem of finding designs with small number of runs is considered here. A main effect plan requires at least (2m + 1) runs for estimating the general mean, linear and quadratic effects of m factors. An orthogonal main effect plan requires, in addition, the number of runs as a multiple of 9. For example, when m=5, a main effect plan requires at least 11 runs and an orthogonal main effect plan requires 18 runs. Two general factor screening designs presented here are nonorthogonal designs with (2m− 1) runs. These designs, called search designs permit us to search for and identify at most two important factors out of m factors under the search linear model introduced in Srivastava (1975). For example, when m=5, the two new plans given in this paper have 9 runs, which is a significant improvement over an orthogonal main effect plan with 18 runs in terms of the number of runs and an improvement over a main effect plan with at least 11 runs. We compare these designs, for 4≤m≤ 10, using arithmetic and geometric means of the determinants, traces, and maximum characteristic roots of certain matrices. Two designs D1 and D2 are identical for m=3 and this design is an optimal design in the class of all search designs under the six criteria discussed above. Designs D1 and D2 are also identical for m=4 under some row and column permutations. Consequently, D1 and D2 are equally good for searching and identifying one important factor out of m factors when m=4. The design D1 is marginally better than the design D2 for searching and identifying one important factor out of m factors when m=5, … , 10. The design D1 is marginally better than the D2 for searching and identifying two important factors out of m factors when m=5, 7, 9. The design D2 is somewhat better than the design D1 for m=6, 8. For m=10, D1 is marginally better than D2 w.r.t. the geometric mean and D2 is marginally better than D1 w.r.t. the arithmetic mean of the maximum characteristic roots.
Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images

Recent melt events on the Greenland ice sheet (GrIS) accentuate the need to constrain estimates of sea level rise through improved characterization of meltwater pathways. This effort will require more precise estimates of the volume of water stored on the surface of the GrIS. We assessed the potential to obtain such information by mapping the bathymetry of supraglacial lakes and streams from WorldView2 (WV2) satellite images. Simultaneous in situ observations of depth and reflectance from two streams and a lake with measured depths up to 10.45 m were used to test a spectrally based depth retrieval algorithm. We performed optimal band ratio analysis (OBRA) of continuous field spectra and spectra convolved to the bands of the WV2, Landsat 7 (ETM+), MODIS, and ASTER sensors. The field spectra yielded a strong relationship with depth ( R 2 = 0.94), and OBRA R 2 values were nearly as high (0.87–0.92) for convolved spectra, suggesting that these sensors' broader bands would be sufficient for depth retrieval. Our field measurements thus indicated that remote sensing of supraglacial bathymetry is not only feasible but potentially highly accurate. OBRA of spectra from 2 m-pixel WV2 images acquired within 3–72 h of our field observations produced an optimal R 2 value of 0.92 and unbiased, precise depth estimates, with mean and root mean square errors < 1% and 10–25% of the mean depth. Bathymetric maps produced by applying OBRA relations revealed subtle features of lake and channel morphology. In addition to providing refined storage volume estimates for lakes of various sizes, this approach can help provide estimates of the transient flux of meltwater through streams.
Hide and Seek: Exploring Connections Between Embodied Rhythmic Associations of Experiences and of Stories

This performative text investigates whether familial narratives climb into our psyche, crawl under our skin, and transform notions of who we think we are. Specifically, it reveals a connection between familial stories, cultural stories, and the embodiment of them. This autoethnographic account of one family’s instances of sexual abuse examines the relationship between embodied memories of abusive experiences and the familial stories shared about the abuse. This exploration suggests that a tension exists between asexualized abuse stories and adolescent sexualized abusive experience. Stylistically, repetition is used to create a rhythm in the work that functions as the “grain” of the author’s story.
Distance between related words in free recall: Trace of the STS

Two experiments on free recall are presented in which pairs of related words are presented within the lists and the number of words intervening between the related pair is systematically varied. In Exp. I the relation was a mnemonic, or associative, relation. In Exp. II the relation was repetition. A second variable in both experiments was presentation rate. In both experiments, systematic, monotonic effects of the number of intervening items were found. The relevance of the effects to a model that postulates two distinct storage mechanisms—an STS and LTS—is discussed.
Patterns of expression of Hoxa-11 in micromass cultures of chick limb mesenchyme from various stages suggest a role for Hoxa-11 in the specification of the zeugopod.

During chick limb development the expression of Hoxa-11 is specifically associated with the prospective zeugopod (radius+ulna) region. A series of micromass cultures were performed using mesenchyme from whole stage 18/19 or 20/21 limbs or mesenchyme from the tips of stage 22/23, 23/24 or 25 limbs. In such cultures, limb mesenchyme undergoes chondrogenesis paralleling its fate in vivo. Hoxa-11 and collagen type II mRNA were examined by dot blot and in situ analysis at different time points. The highest level of Hoxa-11 mRNA was found in micromass cultures of the tips of stage 22/23 and 23/24 limbs at 48 hours. Between stages 22 and 24, the determining events occur which subsequently lead to the formation of the zeugopod by the mesenchyme present in the tips at these stages. This correlation further supports a possible role of Hoxa-11 in the specification of the zeugopod.
Fluid Flow and Falling Ball Experiments in ER Fluids

The ability of the induced dipole–dipole model to predict various properties of an electrorheological fluid is tested in a series of experiments: the deformation of a single particle chain under fluid flow, the velocity of a falling ball at various electric fields, particle sizes, and concentrations, and flow valves operating at either constant pressure differential or constant flow rate. Analyses of these rather different experimental situations show that with proper application, the induced dipole model can give a fairly accurate description of observed characteristics.
Dietary selenium in humans toenails as an indicator

Mounting laboratory and epidemiologic evidence suggests that selenium may be important in the etiology of both cancer and heart disease. We explored the use of hair and nails as indicators of selenium intake by measuring their selenium levels using neutron activation analysis, a highly sensitive and precise nondestructive technique. Levels in duplicate samples of nails, hair, and blood were all reasonably reproducible. However, selenium-containing shampoos severely contaminated some of the hair specimens, suggesting that use of hair in epidemiologic studies could be misleading. The mean selenium level in toenails from South Dakota (a known high selenium area) was 1.17 ppm (1SE = 0.09). This was significantly higher than mean levels from Boston and Georgia (medium selenium intake area) of 0.74 ppm (0.04) and 0.81 (0.03), respectively. The mean selenium level in toenails from New Zealand (low selenium area) was 0.26 (0.02) and these levels did not overlap those of other areas. The South Dakota specimens showed marked familial aggregation, probably reflecting dietary differences. Since toenails vary in length, clippings from different toes represent different time periods of formation; clippings from all ten toes reflect selenium levels integrated over an extended period. As toenails are easily collected, transported, and stored, and reflect longterm intake, they can be useful in epidemiologic studies of selenium and chronic disease.
EFFECTS OF ADDING A SECOND REINFORCEMENT ALTERNATIVE: IMPLICATIONS FOR HERRNSTEIN'S INTERPRETATION OF re

Herrnstein's hyperbola describes the relation between response rate and reinforcer rate on variable-interval (VI) schedules. According to Herrnstein's (1970) interpretation, the parameter re represents the reinforcer rate extraneous to the alternative to which the equation is fitted (the target alternative). The hyperbola is based on an assumption that extraneous reinforcer rate remains constant with changes in reinforcer rate on the target alternative (the constant-re assumption) and that matching with no bias and perfect sensitivity occurs between response and reinforcer ratios. In the present experiment, 12 rats pressed levers for food on a series of 10 VI schedules arranged on the target alternative. Across conditions, six VI values and extinction were arranged on a second alternative. Reinforcer rate on the second alternative, r2, negatively covaried with reinforcer rate on the target alternative for five of the six VI values on the second alternative, and significant degrees of bias and undermatching occurred in response ratios. Given covariation of reinforcer rate on the second and target alternatives, the constant-re assumption can be maintained only by assuming that reinforcer rate from unmeasured background sources, rb, covaries with reinforcer rate on the second alternative such that their sum, re, remains constant. In a single-schedule arrangement, however, re equals rb and thus rb is assumed to remain constant, forcing a conceptual inconsistency between single- and concurrent-schedule arrangements. Furthermore, although an alternative formulation of the hyperbola can account for variations in bias and sensitivity, the modified equation also is based on the constant-re assumption and therefore suffers from the same logical problem as the hyperbola when reinforcer rate on the second alternative covaries with reinforcer rate on the target alternative.
Creating custom SGML DTDs for documentation products

A case is presented for cost-effectively creating custom DTDs for an organization by non-SGML experts using tools that automatically create DTDs from tagged text. Such tools make it practical and easy to create DTDs without having to hire consultants or invest heavily to develop internal SGML expertise. The specific tool focused on is the SGML Document Grammar Builder, a tool developed at OCLC Online Computer Library Center, Inc.
Behavioral Characteristics and Neurobiological Substrates Shared by Pavlovian Sign-Tracking and Drug Abuse

Drug abuse researchers have noted striking similarities between behaviors elicited by Pavlovian sign-tracking procedures and prominent symptoms of drug abuse. In Pavlovian sign-tracking procedures, repeated paired presentations of a small object (conditioned stimulus, CS) with a reward (unconditioned stimulus, US) elicits a conditioned response (CR) that typically consists of approaching the CS, contacting the CS, and expressing consummatory responses at the CS. Sign-tracking CR performance is poorly controlled and exhibits spontaneous recovery and long-term retention, effects that resemble relapse. Sign-tracking resembles psychomotor activation, a syndrome of behavioral responses evoked by addictive drugs, and the effects of sign-tracking on corticosterone levels and activation of dopamine pathways resemble the neurobiological effects of abused drugs. Finally, the neurobiological profile of individuals susceptible to sign-tracking resembles the pathophysiological profile of vulnerability to drug abuse, and vulnerability to sign-tracking predicts vulnerability to impulsive responding and alcohol self-administration. Implications of sign-tracking for models of drug addiction are considered.
Depressive Symptoms and Sex Affect Completion Rates and Clinical Outcomes in Cardiac Rehabilitation

Symptoms of depression are often seen in patients with coronary heart disease. Symptoms appear more commonly in women and are negatively associated with measures of cardiovascular health. Using multiple logistic regression analyses, the authors evaluated the independent effects of depression (as measured by the Beck Depression Inventory [BDI-II]) and sex on cardiac rehabilitation (CR) completion. In addition, in those who completed CR, the authors evaluated whether depressive symptoms and sex affected clinical outcomes. Women as well as participants with enrollment BDI-II scores > or =14 had significantly higher rates of CR noncompletion. Patients with BDI-II scores > or =14 who completed CR achieved significant improvements in lipid profile, body mass index, and exercise capacity regardless of sex. Women and individuals with BDI-II scores > or =14 are at risk for CR noncompletion and should be encouraged to complete CR, because cardiovascular benefits comparable to those seen in men and individuals with low BDI-II scores were achieved when these patients completed the CR program.
A Note on Matrix Rigidity

In this paper we give an explicit construction ofn×n matrices over finite fields which are somewhat rigid, in that if we change at mostk entries in each row, its rank remains at leastCn(log q k)/k, whereq is the size of the field andC is an absolute constant. Our matrices satisfy a somewhat stronger property, we will explain and call “strong rigidity”. We introduce and briefly discuss strong rigidity, because it is in a sense a simpler property and may be easier to use in giving explicit construction.
The Death Penalty: A Multi-Level Analysis of Public Opinion

Considerable research has examined public opinion of the death penalty using simplistic questions such as, “Do you favor or oppose the death penalty.” Simply categorizing people into favoring or opposing capital punishment does little to address the array of factors and circumstances that are part of every murder. We examine variables concerning the nature of homicides from a set of 40 murder vignettes used to gauge respondents’ level of support for capital punishment in murder cases. The data are structured such that vignette responses are nested within individuals, meaning a multi-level analysis is appropriate. We used HLM to explore how vignette-level or homicide related characteristics influence support for the death penalty, as well as how individual-level characteristics condition these factors. Analyses revealed that individual-level variables were non-significant when analyzed independently; however, cross-level interactions indicated significant individual-level influences on homicide-level characteristics as they relate to respondents’ support for the death penalty.
Agrobacterium tumefaciens VirB9, an Outer-Membrane-Associated Component of a Type IV Secretion System, Regulates Substrate Selection and T-Pilus Biogenesis

Agrobacterium tumefaciens translocates DNA and protein substrates between cells via a type IV secretion system (T4SS) whose channel subunits include the VirD4 coupling protein, VirB11 ATPase, VirB6, VirB8, VirB2, and VirB9. In this study, we used linker insertion mutagenesis to characterize the contribution of the outer-membrane-associated VirB9 to assembly and function of the VirB/D4 T4SS. Twenty-five dipeptide insertion mutations were classified as permissive for intercellular substrate transfer (Tra+), completely transfer defective (Tra-), or substrate discriminating, e.g., selectively permissive for transfer only of the oncogenic transfer DNA and the VirE2 protein substrates or of a mobilizable IncQ plasmid substrate. Mutations inhibiting transfer of DNA substrates did not affect formation of close contacts of the substrate with inner membrane channel subunits but blocked formation of contacts with the VirB2 and VirB9 channel subunits, which is indicative of a defect in assembly or function of the distal portion of the secretion channel. Several mutations in the N- and C-terminal regions disrupted VirB9 complex formation with the outer-membrane-associated lipoprotein VirB7 or the inner membrane energy sensor VirB10. Several VirB9.i2-producing Tra+ strains failed to elaborate T pilus at detectable levels (Pil-), and three such Tra+ Pil- mutant strains were rendered Tra- upon deletion of virB2, indicating that the cellular form of pilin protein is essential for substrate translocation. Our findings, together with computer-based analyses, support a model in which distinct domains of VirB9 contribute to substrate selection and translocation, establishment of channel subunit contacts, and T-pilus biogenesis.
The size effect of hematite and corundum inclusions on the efflorescence relative humidities of aqueous ammonium sulfate particles

Mineral dusts inside aqueous atmospheric particles provide surfaces that induce crystallization during episodes of decreasing relative humidity (RH). Submicron aqueous ammonium sulfate particles containing hematite (α-Fe 2 O 3 ) and corundum (α-Al 2 O 3 ) inclusions are investigated in an aerosol flow tube at 298 K. As compared to 35% RH where homogeneous nucleation is rapid, the heterogeneous nuclei regulate the RH from 35% up to 60% RH as the inclusion size varies from 50 to 450 nm. The strong size dependence can be rationalized by an active site model. Model optimization yields 10 10.4 sites cm -2 and m < 0 for α-Al 2 O 3 and 10 9 sites cm -2 and m = 0.04 for α-Fe 2 O 3 particles.
NF-Y involvement in the polyunsaturated fat inhibition of fatty acid synthase gene transcription.

Abstract Dietary polyunsaturated fats (PUFA) reduce the hepatic content of SREBP-1 65–75%, and this is paralleled by a comparable decrease in the expression of fatty acid synthase (FAS) gene. The close association between the nuclear content of SREBP-1 and FAS transcription has led to the conclusion that PUFA inhibit lipogenic gene transcription by suppressing SREBP-1 expression, but this conclusion is based upon correlative data. When in fact the SREBP-1/USF sites of the insulin response element of FAS were mutated, only 25% of the PUFA inhibition of FAS promoter activity was lost. On the other hand, mutating the −99/−93 NF-Y site reduced overall promoter activity 85%, and eliminated 50% of the PUFA suppression of FAS promoter activity. In addition, extended cloning and transfection-reporter assays revealed that the FAS gene contains a second PUFA response region (PUFA-RR) in the distal area of −7382/−6970. Interestingly, the distal PUFA-RRFAS has many similarities to the PUFA-RR of l -pyruvate kinase gene while the proximal PUFA-RRFAS is comparable to the PUFA-RR of the S14 and stearoyl-CoA desaturase genes.
Towards understanding persistent photoconductance in doping modulated amorphous silicon

Abstract We present a simple model to explain the origin of the persistent photoconductance (PPC) in p–n–p–n multilayers made of hydrogenated amorphous silicon: brief light exposures create metastable Staebler-Wronski defects in the p-type material, making it more intrinsic. This in turn pushes the Fermi level of the whole multilayer closer to the conduction band, thus causing the observed metastable increase of the electron dominated coplanar conductance of the multilayer. Much longer light exposures are needed to shift the Fermi level towards midgap due to Staebler-Wronski defects in the n-type layers, leading to a consequent decrease in the PPC effect. In support of our model we present experimental results on the creation rate and annealing kinetics of the light-induced metastable conductance changes in a multilayer and in p-type and n-type single layers.
Generation of Synthetic Spike Trains with Defined Pairwise Correlations

Recent technological advances as well as progress in theoretical understanding of neural systems have created a need for synthetic spike trains with controlled mean rate and pairwise cross-correlation. This report introduces and analyzes a novel algorithm for the generation of discretized spike trains with arbitrary mean rates and controlled cross correlation. Pairs of spike trains with any pairwise correlation can be generated, and higher-order correlations are compatible with common synaptic input. Relations between allowable mean rates and correlations within a population are discussed. The algorithm is highly efficient, its complexity increasing linearly with the number of spike trains generated and therefore inversely with the number of cross-correlated pairs.
Organizing a Congressional Candidate Debate as Experiential Learning

This article describes a political debate among congressional candidates that the authors organized in 2006. The debate was structured to maximize student involvement both in the planning stages and during the event itself. After discussing relevant literature on experiential learning, the article describes the debate format and details the issues encountered in planning and organization. Given the large number of stakeholders, a number of challenges emerged in dealing with the candidates, media, students, and university bureaucracy. Our description of these issues is designed to assist others wishing to organize similar debates. The article also examines student learning outcomes from the perspectives of those involved in debate planning and those who attended as part of an American Government class. We find that participation enhanced political knowledge and engagement for both groups. Finally, the paper considers how assessment of the debate's impact could be addressed more effectively and systematical...
Intellectually Precocious Preschool Children: Early Development and Later Intellectual Accomplishments.

Summary Among 114 children with Stanford-Binet IQs of 140 or more at four years of age were 100 who had been administered the research version of the Bayley Scales of Mental and Motor Development at 8 months and 95 who had received the WISC and Wide Range Achievement Test at 7 years. The results indicated that these children were not generally advanced as infants. Parental education correlated substantially with the IQ and achievement scores of boys; among girls, parental education tended to correlate only with achievement scores. The significant parent-child correlations among the intellectually precocious indicate that they should not be treated as a homogeneous group. Sex differences militate against simplified genetic explanations for intellectual precocity and suggest that the boys were more responsive than girls to environmental factors.
Presenilin-1/γ-Secretase Controls Glutamate Release, Tyrosine Phosphorylation, and Surface Expression of N-Methyl-d-aspartate Receptor (NMDAR) Subunit GluN2B

Abnormally high concentrations of extracellular glutamate in the brain may cause neuronal damage via excitotoxicity. Thus, tight regulation of glutamate release is critical to neuronal function and survival. Excitotoxicity is caused mainly by overactivation of the extrasynaptic NMDA receptor (NMDAR) and results in specific cellular changes, including calcium-induced activation of calpain proteases. Here, we report that presenilin-1 (PS1) null mouse cortical neuronal cultures have increased amounts of calpain-dependent spectrin breakdown products (SBDPs) compared with WT cultures. NMDAR antagonists blocked accumulation of SBDPs, suggesting abnormal activation of this receptor in PS1 null cultures. Importantly, an increase in SBDPs was detected in cultures of at least 7 days in vitro but not in younger cultures. Conditioned medium from PS1 null neuronal cultures at 8 days in vitro contained higher levels of glutamate than medium from WT cultures and stimulated production of SBDPs when added to WT cultures. Use of glutamate reuptake inhibitors indicated that accumulation of this neurotransmitter in the media of PS1 null cultures was due to increased rates of release. PS1 null neurons showed decreased cell surface expression and phosphorylation of the GluN2B subunit of NMDAR, indicating decreased amounts of extrasynaptic NMDAR in the absence of PS1. Inhibition of γ-secretase activity in WT neurons caused changes similar to those observed in PS1 null neurons. Together, these data indicate that the PS1/γ-secretase system regulates release of glutamate, tyrosine phosphorylation, and surface expression of GluN2B-containing NMDARs. Background: Presenilin-1/γ-secretase is critical to neuronal function. Results: Inhibition of presenilin-1/γ-secretase increases release of glutamate, stimulating NMDAR and calpain while decreasing phosphorylation and surface expression of neuronal GluN2B. Conclusion: Presenilin-1/γ-secretase regulates glutamate release, NMDAR-dependent calpain activity, and modification of GluN2B. Significance: This study reveals a role for γ-secretase in release of glutamate, a neurotransmitter central to neuronal function, and excitotoxicity, a stress important to neurodegeneration.
First observation of a near-harmonic vibrational nucleus.

Evidence is presented for five closely spaced states in $^{118}\mathrm{Cd}$ near ${E}_{\mathrm{ex}\mathrm{\ensuremath{\simeq}}2}$ MeV, which are interpreted as a near-harmonic three-phonon quintuplet. Candidates for even higher-lying multiphonon states are also found. The experimental spectrum is compared with an anharmonic vibrator [or U(5) spectrum] and an interacting-boson-approximation calculation incorporating a two-particle, four-hole intruder configuration.
Should vitamin D supplementation be a regular part of asthma care

Vitamin D (vitD3) deficiency occurs frequently and has profound effects on health, especially asthma. This article examines how current knowledge of vitD3 actions and the worldwide distribution of vitD3 deficiency influences everyday clinical allergy practice. Within the limits of current knowledge, the article concisely explains the molecular nature of vitD3 actions, reviews key vitD3 research as it applies to clinical care, answers questions about the potential clinical impact of low vitD3 levels, and discusses use and safety of vitD3 supplements.
Use of Capacitance to Measure Surface Forces. 1. Measuring Distance of Separation with Enhanced Spatial and Time Resolution

We describe a simple method to measure the separation and forces between two macroscopic surfaces mounted in a crossed cylinder arrangement. It is shown that by measuring the capacitance between silver layers deposited on the backside of thin mica substrates, it is possible to achieve spatial resolution of less than 0.1 nm and time resolution of 1 ms. The growth of capacitance with decreasing distance of separation follows the predicted dependence for an ideal sphere and plate capacitor. To demonstrate the capability of obtaining force−distance profiles with this technique, octamethylcyclotetrasiloxane (OMCTS) has been confined between the mica sheets. We find that the process of collapse of the confined liquid, from four molecular layers to three, occurs more rapidly than 1 ms. This technique is also shown to give excellent results for opaque surfaces used in the surface forces apparatus (SFA), and we show that the adhesion energy between two surfaces of oxidized silicon is 3 mJ/m2. Applications of this ...
How much life insurance

This report is an attempt to assist the dentist in answering the question for himself. Life insurance benefits are paid to fulfill the responsibilities of the deceased and the older man usually has less responsibility than the younger man.
Biomicroscopic Observations on Vasocon-strictive and Thrombogenic Effects produced by Long-chain Saturated Fatty Acids within the Vasculature of the Wing of an Unanæsthetized Bat

POOLE1 reported in 1955 that when certain fatty acids in low concentration are added to plasma the clotting time is shortened. In 1959 he2 modified Chandler's3 system to make and to study artificial thrombi. In 1961, with Connor4, he showed that when straight-chain saturated fatty acids with 16 or more carbon atoms were added to mixtures of blood in Chandler's system thrombus formation was accelerated and the thrombi so formed larger. Short -chain fatty acids, C6 and C7, had no activity and unsat-urated acids were inactive, or very nearly so.
Electoral equilibrium in double member districts

The median-voter result, and the issue of stability in electoral competition generally, have been examined from a number of different perspectives. Out of all these examinations, however, only a few focus on institutional variables. This essay demonstrates that the median-voter result is robust under a significant institutional change that entails altering the basic assumption of single-member districts. After developing a model of electoral competition in a two-member, first-two-past-the-post district, I show that, if there are three candidates, the set of Nash equilibria is the set of strategy triples (x 1, x 2, x 3), with x 1 = x 2 = x 3 = x*, and such that x* lies between the quantiles of order 1/3 and 2/3. If there are four candidates, I show that a unique Nash equilibrium exists with all candidates adopting a position at the medianvoter's ideal point.
n-3, but not n-6 lipid Particle Uptake Requires Cell Surface Anchoring

Omega-3 (n-3) fatty acids are emerging as bioactive agents protective against cardiovascular disease. However, their cellular delivery pathways are poorly defined. Here we questioned whether the uptake of n-3 TGRP is mediated by cell surface proteoglycans (PG) using LDLR+/+ and LDLR−/− cell models. LDLR+/+ but not LDLR−/− cells showed higher n-6 over n-3 TGRP uptake. Removal of cell surface proteins and receptors by pronase markedly enhanced the uptake of n-3 but not n-6 TGRP. Lactoferrin blockage of apoE-mediated pathways decreased the uptake of n-6 TGRP by up to 85% (p < 0.05) but had insignificant effect on n-3 TGRP uptake. PG removal by sodium chlorate in LDLR+/+ cells substantially reduced n-3 TGRP uptake but had little effect on n-6 TGRP uptake. Thus, while n-6 TGRP uptake is preferentially mediated by LDLR-dependent pathways, the uptake of n-3 TGRP depends more on PG and non- LDLR cell surface anchoring.
Why is the definition of life so elusive? Epistemological considerations.

Abstract A central question of astrobiology concerns the origin and distribution of life in the Universe. For this reason, astrobiology can be considered to fall within the science called transitional biology. If we accept that life originated by a process of prebiotic chemical evolution, the next question concerns the nature of the transitional pathway from inanimate chemical systems to the first forms of life on Earth. These possible transitional states are the subject matter of transitional biology as a discipline. A related question concerns attempts to synthesize living systems in the laboratory. In contrast to traditional biology, the definition of life has an important methodological role in transitional biology, yet we still do not have a generally accepted definition despite the immense accumulation of empirical data in the life sciences. This review analyzes three approaches to defining life and concludes that all three are problematic in that they attempt to define life with undefined terms, co...
Probable mechanical transmission of a virus-like agent from rose rosette disease-infected multiflora rose to Nicotiana species

Summary As part of efforts to identify the causal agent of the rose rosette disease (RRD) of multiflora rose (Rosa multiflora Thunb.), root tip extracts from both symptomatic and nonsymptomatic roses were used to mechanically inoculate leaves of Nicotiana glutinosa. Pale green spots were observed along the margins of the major leaf veins only on leaves inoculated with extracts prepared from symptomatic rose plants. Light microscopy revealed abnormal development of the palisade and spongy mesophyll cells in the symptomatic tissue, although no virus-like particles (VLPs) were observed by electron microscopy. However, VLPs were observed in cells from tissue adjacent to the leaf veins and bordered by the pale green spots. Inoculation of N. benthamiana with extracts from symptomatic N. glutinosa initially did not result in visible symptoms on N. benthamiana inoculated leaves. However, approximately 4 wk post inoculation, splitting of leaf tissue across and along major leaf veins in expanding leaves occurred. In later stages of leaf expansion some leaves split in regions not associated with veins. Light microscopy of thick sections revealed separation between palisade cells and groups of small dead cells in the mesophyll tissue of expanding systemically infected leaf blades. Electron microscopy revealed crystalline arrays in the cytoplasm of mesophyll cells. No abnormal cellular changes were observed in plants inoculated with extracts prepared from nonsymptomatic rose plants.
Ethanol and acetaldehyde alter brain mitochondrial redox responses to direct cortical stimulation in vivo.

Abstract To determine whether and how ethanol and acetaldehyde alter brain oxidative metabolic activity, reduction/oxidation shifts of components of the mitochondrial respiratory chain were optically measured, in situ , from cat cerebral cortex. Oxidative shifts of nicotinamide adenine dinucleotide (NADH) were recorded in response to increased energy demand provoked by stimulation of the cortical surface by electrical pulses. Ethanol or acetaldehyde did not alter the direction of the responses but each slowed the rates of oxidation with little effect upon the rates of subsequent re-reduction. There was no apparent change produced by either drug upon the kinetics of the negative shifts of the cortical steady potential in response to the stimulation. However, stimulus-evoked electrical and metabolic responses were decreased in amplitude with increasing drug doses. It is suggested that the slowed mitochondrial oxidation results from inhibition of Na + , K + -ATPase. This supports the concept that ethanol or acetaldehyde inhibit the processes that lead to increased oxygen consumption following cell depolarization in vivo , as has been demonstrated in vitro .