cssi/SciSciGPT-SciSciNet huggingface dataset:
Analyzing intrusions using operating system level information flow

Computers continue to get broken into, so intrusion analysis is a part of most system administrators' job description. System administrators must answer two main questions when analyzing intrusions: "how did the attacker gain access to my system?", and "what did the attacker do after they broke in?". Current tools for analyzing intrusions fall short because they have insufficient information to fully track the intrusion and because they cannot separate the actions of attackers from the actions of legitimate users. We designed and implemented a system for analyzing intrusions by using OS-level information flow to highlight the activities of an attacker. OS-level information flow is a collection of causal events which connect operating system objects. These causal events can be linked to form an information-flow graph which highlights the events and objects that are part of an attack. Information flow graphs can be used to help system administrators determine how an intruder broke into a system and what they did after the compromise. We developed BackTracker to determine how an intruder broke into a system. BackTracker starts with a suspicious object (e.g., malicious process, trojaned executable file) and follows the attack back in time, using causal events, to highlight the sequence of events and objects that lead to the suspicious state. Showing a graph of these causally-connected events and objects provides a system-wide view of the attack and significantly reduces the amount of data an administrator must examine in order to determine which application was originally exploited. We also developed ForwardTracker to determine the attacker's actions after the compromise. ForwardTracker starts from the application which was exploited and tracks causal events forward in time to display the information flow graph of events and objects that result from the intrusion. Furthermore, we designed and implemented Bi-directional Distributed BackTracker (BDB) which continues the backward and forward information flow graphs across the network to highlight the set of computers on a local network which are likely to have been compromised by the attacker.
An Early Intervention Model for Infants who are Deaf-Blind:

This article presents an early intervention model for infants who are deaf-blind that focuses on the significance of infant-caregiver interaction. It proposes intervention strategies to develop con...
The Benefits and Costs of Complexity

Here is how to boil a frog. Place the frog in a pan of tepid water. Raise the temperature so gradually that the frog does not realize it is being cooked. It may even fall into a stupor, as a person might in a hot bath. Eventually it will die. According to experiments done in the nineteenth century, you can indeed boil a frog this way. Biologists today claim that you can’t. Either way, please don’t try it.
N-Limited Versus Ga-Limited Growth on ${\rm GaN}(000\bar{1})$ by MBE Using NH3

GaN was grown on by MBE using NH3 and a Ga Knudsen cell. The growth kinetics on samples of this polarity were investigated with desorption mass spectroscopy (DMS) and reflection high energy electron diffraction (RHEED). Both techniques were used to observe and control surface termination, Ga condensation and surface temperature. GaN growth and decomposition rates were measured by DMS. Two stable surface terminations were found to exist — N-terminated and Ga-terminated . The N-terminated surface also contained hydrogen which desorbed during growth at a rate proportional to the growth rate. Low temperature reconstructions were only observed by adding weakly adsorbed Ga on top of the Ga-terminated surface. During growth two distinct growth regimes were identified: growth under excess NH3 and growth under excess Ga. Growth is limited in both regimes by GaN decomposition at high temperatures with an activation energy of 3.4 eV. Growth in the excess Ga regime ceased below the Ga condensation temperature. Under conditions of excess NH3, strong but damped oscillations in the specular RHEED intensity were observed on smooth surfaces. Contrary to previous suggestions, the period of these oscillations did not correspond exactly to integral layer deposition and was not characteristic of a narrow growth front. Further, the growth mode changed from island nucleation to step flow with an activation energy of 1.2 eV. Under conditions of excess Ga, the diffraction was 2-D but RHEED intensity oscillations were not observed, indicating a step flow growth mode. In this latter regime RHEED measurements were very sensitive to termination changes on the surface, and the growth rate was found to decrease linearly with increasing Ga flux. This reduction is explained by a model in which weakly adsorbed Ga blocks reaction at strongly bound Ga. A map is presented to provide a framework for categorizing the overall growth.
Surface Smoothness Evaluation of Etched and Unaltered Sand Specimens with Mechanical Behavior Assessment

Particle smoothness refers to the surface texture of a sand particle on a small scale. This parameter may be used in conjunction with roundness (angularity) and sphericity in describing particle shape for engineering purposes. Smoothness is challenging to measure and quantify. This note describes preliminary evaluation approaches used to compare two identically graded sand specimens; one with an unaltered, smooth surface texture, and the other chemically etched to create a rougher surface texture. Visual observation indicated that the unaltered specimens were essentially the same as the etched specimens in terms of macroscale particle shape features (i.e., roundness and sphericity). On the other hand, the particles were significantly different in terms of the surface texture and roughness, as shown by visual techniques using scanning electron microscope and optical microscopy images. A tentative, easy-to-implement, visual particle smoothness scale is offered, designed to complement the roundness and sphericity estimates and measures commonly used to describe particle shape. Next, several simple laboratory index tests are completed on the unaltered and the etched specimens to observe differences in mechanical behavior. Limit density, flow rate, and angle of repose tests are undertaken. The results of the testing indicate measurable differences in the mechanical behavior of the unaltered versus the etched specimens. This further supports the importance of particle surface texture on the mechanical behavior of poorly graded sands. Additional research is underway to more completely quantify the contribution of particle smoothness of sands with respect to the other macroscale particle shape features.
Utility and Prognostic Significance of Neutrophil-to-Lymphocyte Ratio in Dogs with Septic Peritonitis

Systemic inflammation is known to cause WBC abnormalities, specifically neutrophilia and lymphopenia. The neutrophil-to-lymphocyte ratio (NLR) is a simple and affordable biomarker that has been used in human clinical settings of sepsis but has not been investigated in veterinary species. We evaluated NLR in dogs with septic and nonseptic systemic inflammatory diseases and compared with a healthy dog population. An NLR ≥6 had an 84.39% sensitivity and 86.95% specificity to identify dogs with systemic inflammatory states; however, no ratio distinguished septic and nonseptic causes. The NLR was not associated with length of hospitalization, morbidity based on the acute patient physiologic laboratory evaluation scoring system, or mortality. The disassociation may be due to the retrospective nature of the study, including a restricted population size and acquisition of only a one-time blood sample. NLR is currently of limited use for diagnosis and prognosis in systemic inflammatory states in dogs, and larger, prospective studies are necessary to further evaluate NLR.
The multi-scalar organization of aging-related services in US rural places

Abstract Many rural communities in the United States are experiencing significant population aging, and these changes in age structure are often associated with shifts in economic activity. The demands for certain goods and services are expected to vary across age groups, and public- and private-sector service providers may make decisions based on their interpretation of demographic trends. The extent to which these perceived changes in the demand for services align with their provision has significant implications for the well-being of the older residents of aging communities. In this article, we draw on case studies of four aging communities across the rural United States to examine the provision of, and access to, aging-related services. We analyze how service provision is organized both within and between communities, how this organization is associated with the kinds of services available, the ways that older residents gain access to services, and the set of barriers to access they face. Our research suggests that aging-related service provision in rural communities is facilitated by partnerships among local community institutions and between them and external organizations. While in many cases population aging is associated with economic decline, the impact of demographic change is not mechanistic nor automatic. Our research shows that aging rural communities can be resilient, and that cooperative, multi-scalar relationships are a key to maintaining quality of life among older residents of communities with aging populations.
The Biblical Mysticism of John of the Cross

In the Prologue to his Ascent of Mount Carmel John of the Cross mentions the three sources of his mystical teaching–experience, theological science, and scripture – noting that scripture is his fun...
Motivations for deep-space travel

When trying to predict the future of spaceflight, we are faced with the same dilemma experienced by visionaries in all fields. In order to model what humans may (or may not) do at some point in the indeterminate future, we must examine the nature of what makes humans move along certain paths. Always uncertain, such ‘futurology’ is even more difficult today as human civilisation seems poised on the threshold of a transformation from independent nation states to a global entity. What might encourage this emerging global entity to expand its realm of operations from the friendly, solar-heated spaces near the Earth to the alien, frigid void beyond the planets and between the stars?
Effects of mechanobiological signaling in bone marrow on skeletal health

Bone marrow is a cellular tissue that forms within the pore space and hollow diaphysis of bones. As a tissue, its primary function is to support the hematopoietic progenitor cells that maintain the populations of both erythroid and myeloid lineage cells in the bone marrow, making it an essential element of normal mammalian physiology. However, bone's primary function is load bearing, and deformations induced by external forces are transmitted to the encapsulated marrow. Understanding the effects of these mechanical inputs on marrow function and adaptation requires knowledge of the material behavior of the marrow at multiple scales, the loads that are applied, and the mechanobiology of the cells. This paper reviews the current state of knowledge of each of these factors. Characterization of the marrow mechanical environment and its role in skeletal health and other marrow functions remains incomplete, but research on the topic is increasing, driven by interest in skeletal adaptation and the mechanobiology of cancer metastasis.
The Landmark Series: MSLT-1, MSLT-2 and DeCOG (Management of Lymph Nodes)

Management of regional lymph nodes in patients with melanoma has evolved significantly in recent years. The value of nodal intervention, long utilized for its perceived therapeutic benefit, has now shifted to that of a critical prognostic procedure used to guide clinical decision making. This review focuses on the three landmark, randomized controlled trials evaluating the role of surgery for regional lymph nodes in melanoma: Multicenter Selective Lymphadenectomy Trial I (MSLT-I), German Dermatologic Cooperative Oncology Group-Selective Lymphadenectomy Trial (DeCOG-SLT), and Multicenter Selective Lymphadenectomy Trial II (MSLT-II).
Determination of Yield and Some Properties of Different Silage Corn Varieties in Isparta Ecological Conditions

Bu arastirma, farkli silajlik misir cesitlerinin verim ve bazi ozelliklerini belirlemek amaciyla 2018 yilinda Isparta Uygulamali Bilimler Universitesi Ziraat Fakultesi, Egitim, Arastirma ve Uygulama Ciftligi’nde yurutulmustur. Calismada materyal olarak 6 silajlik misir cesidi (DKC721, Hido, Kilowat, Kolosseus, LG30709 ve PNR31143) kullanilmistir. Denemeler, tesaduf bloklari deneme desenine gore 3 tekrarlamali olarak kurulmustur. Arastirmada yesil ot verimi, bitki boyu, sap, yaprak ve kocan oranlari, yaprak sayisi, kocan uzunlugu ve kocan capi degerleri belirlenmistir. Varyans analiz sonuclarina gore cesitler arasinda yesil ot verimi, bitki boyu, yaprak sayisi, kocan boyu ve kocan capi degerleri bakimindan %1 duzeyinde, kocan orani bakimindan ise %5 duzeyinde istatistiksel olarak onemli farkliliklar bulunurken, sap ve yaprak oranlari acisindan cesitler arasinda gozlemlenen farkliliklarin istatistiksel olarak onemsiz oldugu belirlenmistir. Incelenen ozellikler bakimindan, yesil ot verimi 8624,9-10681,0 kg/da, bitki boyu 234,3-294,3 cm, yaprak sayisi 13,0-15,2 adet/bitki, kocan uzunlugu 20,7-26,0 cm ve kocan capi 46,5-55,6 mm arasinda degismistir. Ozellikle verim ve sap, yaprak ve kocan oranlari acisindan Hido cesidi one cikarken bunu Kolosseus ve LG30709 cesitlerinin takip ettigi gozlemlenmistir. DKC721 cesidinin ise incelenen ozellikler bakimindan geride kaldigi soylenebilir.
Energy Storage Systems in Emerging Electricity Markets: Frequency Regulation and Resiliency

Different Federal Energy Regulator Commission (FERC) orders have provided the opportunity for battery energy storage systems (ESSs) to participate in markets. The ability to be a fast-ramping generator or load allows ESSs to provide different grid services. This paper discusses opportunities for ESSs to participate in multiple existing and future electricity markets. The economic value of ESSs can be further increased by pragmatically participating in markets and services considering operational and degradation aspects. The impact of ESS on grid resilience is discussed, including resilience-as-a -service. ESSs can restore the grid to its 100% resilient state during system events, and may also reduce the resilience degradation time during extreme events.
Selective Mechanical Backside Grinding of CSP-BGA and SOIC-CAV Devices in Preparation for Backside Failure Analysis

Failure Analysis is the process of determining the cause of failure, collecting and analyzing data, and developing conclusions to eliminate the failure mechanism causing specific device or system failure.1 Semiconductor failure analysis initially involves pinpointing the nature of the failure. The initial phase of semiconductor failure analysis calls for the failure verification in which the failure is identified and categorized. The next phase of analysis seeks to localize the exact origin and causes of the failure. To localize the exact origin and causes of the failure, the device will be subjected to various forms of failure analysis, some non-destructive, and others destructive. As one of the failure analysis rules, all possible non-destructive analyses should be performed first before the destructive analyses. Moving on to the destructive FA techniques can render the device not suitable for further electrical analysis. This paper proposes a selective backside mechanical grinding on a previously opened device without damaging solder bumps and electrical connections linked to the electrical fault and mechanical grinding of a device with sensitive package constructions (sensors, beams) for a successful backside fault isolation and further electrical analysis.
GIS tool to predict photosynthetically active radiation in a Dry Valley

Understanding primary productivity is a core research area of the National Science Foundation's Long-Term Ecological Research Network. This study presents the development of the GIS-based Topographic Solar Photosynthetically Active Radiation (T-sPAR) toolbox for Taylor Valley. It maps surface photosynthetically active radiation using four meteorological stations with ~20 years of data. T-sPAR estimates were validated with ground-truth data collected at Taylor Valley's major lakes during the 2014–15 and 2015–16 field seasons. The average daily error ranges from 0.13 mol photons m-2 day-1 (0.6%) at Lake Fryxell to 3.8 mol photons m-2 day-1 (5.8%) at Lake Hoare. We attribute error to variability in terrain and sun position. Finally, a user interface was developed in order to estimate total daily surface photosynthetically active radiation for any location and date within the basin. T-sPAR improves upon existing toolboxes and models by allowing for the inclusion of a statistical treatment of light attenuation due to cloud cover. The T-sPAR toolbox could be used to inform biological sampling sites based on radiation distribution, which could collectively improve estimates of net primary productivity, in some cases by up to 25%.
Characterization of Aggregated Antibody-Silicone Oil Complexes: From Perspectives of Morphology, 3D Image, and Fcγ Receptor Activation.

Abstract Pre-filled syringes (PFS) have been in widespread use as an administration device for therapeutic antibodies in recent decades. Generally, the inner barrel and syringe of PFS are coated with silicone oil (SO) for lubrication. Multiple studies have focused on the fact that the SO adsorbs denatured antibody molecules, and induces antibody aggregation. Aggregated antibodies are recognized as a potential risk for evoking immunogenic responses in patients. The characteristics of the aggregated antibody-SO complexes, including their concentration, population, shape, three-dimensional (3D) image, and Fcγ Receptors (FcγRs) activation have been obscurely acknowledged so far. In the present work, we prepared aggregated antibody-SO complexes by agitation and analyzed using multifaceted techniques such as flow imaging, confocal fluorescence microscopy, and cell-based assays for FcγRs activation. The results emphasized that the SO accelerates the increase in sub-visible particles and antibody aggregation. The confocal fluorescence microscopy analysis revealed the high-resolution 3D images of aggregated antibody-SO complexes. The FcγRs reporter cell assay clarified that the pre-mixed and agitated Ab + SO have higher FcγRs activation capability compared to the agitated Ab. Overall, this study advances the view that SO has an effect to increase the risk of agitation-induced aggregated antibody particles.
Crosstalk between vrille transcripts, proteins, and regulatory elements controlling circadian rhythms and development in Drosophila.

Summary The vrille (vri) gene encodes a transcriptional repressor required for Drosophila development as well as circadian behavior in adults. Alternate first exons produce vri transcripts predicted to produce a short VRI isoform during development and long VRI in adults. A vri mutant (vriΔ679) lacking long VRI transcripts is viable, confirming that short VRI is sufficient for developmental functions, yet behavioral rhythms in vriΔ679 flies persist, showing that short VRI is sufficient for clock output. E-box regulatory elements that drive rhythmic long VRI transcript expression are required for developmental expression of short VRI transcripts. Surprisingly, long VRI transcripts primarily produce short VRI in adults, apparently due to a poor Kozak sequence context, demonstrating that short VRI drives circadian behavior. Thus, E-box-driven long VRI transcripts primarily control circadian rhythms via short VRI, whereas the same E-boxes drive short VRI transcripts that control developmental functions using short VRI.
Estimation of root zone soil moisture from ground and remotely sensed soil information with multisensor data fusion and automated machine learning

Abstract Root zone soil moisture (RZSM) estimation and monitoring based on high spatial resolution remote sensing information such as obtained with an Unmanned Aerial System (UAS) is of significant interest for field-scale precision irrigation management, particularly in water-limited regions of the world. To date, there is no accurate and widely accepted model that relies on UAS optical surface reflectance observations for RZSM estimation at high spatial resolution. This study is aimed at the development of a new approach for RZSM estimation based on the fusion of high spatial resolution optical reflectance UAS observations with physical and hydraulic soil information integrated into Automated Machine Learning (AutoML). The H2O AutoML platform includes a number of advanced machine learning algorithms that efficiently perform feature selection and automatically identify complex relationships between inputs and outputs. Twelve models combining UAS optical observations with various soil properties were developed in a hierarchical manner and fed into AutoML to estimate surface, near-surface, and root zone soil moisture. The addition of independently measured surface and near-surface soil moisture information to the hierarchical models to improve RZSM estimation was investigated. The accuracy of soil moisture estimates was evaluated based on a comparison with Time Domain Reflectometry (TDR) sensors that were deployed to monitor surface, near-surface and root zone soil moisture dynamics. The obtained results indicate that the consideration of physical and hydraulic soil properties together with UAS optical observations improves soil moisture estimation, especially for the root zone with a RMSE of about 0.04 cm3 cm−3. Accurate RZSM estimates were obtained when measured surface and near-surface soil moisture data was added to the hierarchical models, yielding RMSE values below 0.02 cm3 cm−3 and R and NSE values above 0.90. The generated high spatial resolution RZSM maps clearly capture the spatial variability of soil moisture at the field scale. The presented framework can aid farm scale precision irrigation management via improving the crop water use efficiency and reducing the risk of groundwater contamination.
Stance Detection in COVID-19 Tweets

The prevalence of the COVID-19 pandemic in day-to-day life has yielded large amounts of stance detection data on social media sites, as users turn to social media to share their views regarding various issues related to the pandemic, e.g. stay at home mandates and wearing face masks when out in public. We set out to make use of this data by collecting the stance expressed by Twitter users, with respect to topics revolving around the pandemic. We annotate a new stance detection dataset, called COVID-19-Stance. Using this newly annotated dataset, we train several established stance detection models to ascertain a baseline performance for this specific task. To further improve the performance, we employ self-training and domain adaptation approaches to take advantage of large amounts of unlabeled data and existing stance detection datasets. The dataset, code, and other resources are available on GitHub.(1)
“Driver-passenger” bacteria and their metabolites in the pathogenesis of colorectal cancer

Colorectal cancer (CRC) is a significant public health problem accounting for about 10% of all new cancer cases globally. Though genetic and epigenetic factors influence CRC, the gut microbiota acts as a significant component of the disease's etiology. Further research is still needed to clarify the specific roles and identify more bacteria related to CRC development. This review aims to provide an overview of the "driver-passenger" model of CRC. The colonization and active invasion of the "driver(s)" bacteria cause damages allowing other commensals, known as "passengers," or their by-products, i.e., metabolites, to pass through the epithelium . This review will not only focus on the species of bacteria implicated in this model but also on their biological functions implicated in the occurrence of CRC, such as forming biofilms, mucus, penetration and production of enterotoxins and genotoxins.
Frequency-Dependent Synaptic Dynamics Differentially Tune CA1 and CA2 Pyramidal Neuron Responses to Cortical Input.

Entorhinal cortex (EC) neurons make monosynaptic connections onto distal apical dendrites of CA1 and CA2 pyramidal neurons (PNs) through the perforant path (PP) projection. Previous studies show that differences in dendritic properties and synaptic input density enable the PP inputs to produce a much stronger excitation of CA2 compared to CA1 PNs. Here, using mice of both sexes, we report that the difference in PP efficacy varies substantially as a function of presynaptic firing rate. Although a single PP stimulus evokes a 5-6 fold greater EPSP in CA2 compared to CA1, a brief high-frequency train of PP stimuli evokes a strongly facilitating postsynaptic response in CA1, with relatively little change in CA2. Furthermore, we demonstrate that blockade of NMDARs significantly reduces strong temporal summation in CA1, but has little impact on that in CA2. As a result of the differences in the frequency- and NMDAR-dependent temporal summation, naturalistic patterns of presynaptic activity evoke CA1 and CA2 responses with distinct dynamics, differentially tuning CA1 and CA2 responses to bursts of presynaptic firing versus single presynaptic spikes, respectively. Significance Statement Recent studies have demonstrated abundant entorhinal cortical innervation and efficient dendritic propagation enable hippocampal CA2 pyramidal neurons to produce robust excitation evoked by single cortical stimuli, compared to CA1. Here we uncovered, unexpectedly, that the difference in efficacy of cortical excitation varies substantially as a function of presynaptic firing rate. A burst of stimuli evokes a strongly facilitating response in CA1, but not in CA2. As a result, postsynaptic response of CA1 and CA2 to presynaptic naturalistic firing displays contrasting temporal dynamics, which depends on the activation of NMDARs. Thus our findings provide a synaptic mechanism by which hippocampal neurons dynamically respond to irregular, high-frequency burst firing in entorhinal cortex in behaving animals.
Brian MacLean, September 3, 1929 – April 30, 2021

With the death of Brian MacLean at age 91, Arctic marine geologists lost a long-time friend and valuable colleague. Brian was the epitome of a “gentle man” who loved his work and was always willing...
Muscular wall replacement of the ileocecal valve after necrotizing enterocolitis resembles ileocecal atresia: Report of two cases and management

Abstract Atresia of the ileocecal valve is an extremely rarely described phenomenon, with only 11 cases previously reported in the literature. We present two cases resembling atresia, both of which were in premature infants who presented with obstruction after recovering from necrotizing enterocolitis. The apparent atresia was more likely a discrete stricture of the ileocecal valve. Both were successfully treated with ileocecectomy and primary anastomosis.
The Control of Error in Numerical Methods

Differential equations are types of equations that arise from the mathematical modelling, or simulation, of physical phenomena or from engineering applications; for example: the flow of water, the decay of radioactive substances, bodies in motion, electrical circuits, chemical processes, etc. When we cannot solve differential equations analytically, we must resort to numerical methods. Unfortunately, numerical methods do not give us an exact solution, and an amount of error is introduced in the answer. It is our goal to utilize concepts from Control Theory in order to minimize this error. For our study, we shall focus on ordinary differential equations (ODEs).
Abstract 20236: Differential Expression of Genes Associated With Cardiovascular Disease in Cardiac Allograft Vasculopathy

BACKGROUND: Cardiac allograft vasculopathy (CAV) accounts for significant mortality after heart transplant (HT). The identification of molecular pathways involved in CAV may provide targets for preventive therapies and development of risk markers. METHOD: Gene expression profiling and transcriptome analysis using Illumina HiSeq 2000, was performed in 23 HT recipients, 12 with ISHLT grade 3 CAV and 11 without CAV matched on age, gender, and HT duration. Fastqc, Tophat, Samtools, and CuffDiff were utilized for quality control of raw reads, mapping short reads to reference genomes and testing differential expression between healthy subjects and HT recipients. Ingenuity pathway analysis (IPA) was performed to identify molecular pathways demonstrating differential expression. RESULT: Mean age was 54.6yrs, mean duration of transplant 8.1yrs, 69% were men, and etiology of HT was ischemic in 47.8%. IPA analysis revealed abnormalities in the following pathways: disease and biological functions, molecular and cellular functions, catonical pathways and toxicity. When cardiovascular pathways were evaluated, CAV was associated with differential expression in genes involved in cardiac arteriopathy, inflammation, fibrosis, heart failure, and arrhythmia. (Table 1) Conclusion: Genes associated with inflammation, arteriopathy, fibrosis, heart failure, and arrhythmias are differentially expressed in CAV. Longitudinal evaluation is required to determine the relationship of these genes and pathways to risk and development of CAV and their response to specific therapies.
A suggestion for solving negative transfer problem in VLSI backpropagation neural networks

To overcome negative transfer problem in backpropagation (BP) neural networks, a modified BP algorithm has been proposed. However, for VLSI BP neural networks, this means an extensive design efforts. We analyze in this paper the nature of negative transfer problem and identify a simple technique to solve the negative transfer problem in VLSI BP neural networks. >
γ ray astronomy with muons

Although $\ensuremath{\gamma}$ ray showers are muon poor, they still produce a number of muons sufficient to make the sources observed by GeV and TeV telescopes observable also in muons. For sources with hard $\ensuremath{\gamma}$ ray spectra there is a relative ``enhancement'' of muons from $\ensuremath{\gamma}$ ray primaries as compared to that from nucleon primaries. All shower $\ensuremath{\gamma}$ rays above the photoproduction threshold contribute to the number of muons ${N}_{\ensuremath{\mu}},$ which is thus proportional to the primary $\ensuremath{\gamma}$ ray energy. With $\ensuremath{\gamma}$ ray energy 50 times higher than the muon energy and a probability of muon production by the $\ensuremath{\gamma}$'s of about 1%, muon detectors can match the detection efficiency of a GeV satellite detector if their effective area is larger by ${10}^{4}$. The muons must have enough energy for sufficiently accurate reconstruction of their direction for doing astronomy. These conditions are satisfied by relatively shallow neutrino detectors such as AMANDA and Lake Baikal, and by $\ensuremath{\gamma}$ ray detectors such as MILAGRO. TeV muons from $\ensuremath{\gamma}$ ray primaries, on the other hand, are rare because they are only produced by higher energy $\ensuremath{\gamma}$ rays whose flux is suppressed by the decreasing flux at the source and by absorption on interstellar light. We show that there is a window of opportunity for muon astronomy with the AMANDA, Lake Baikal, and MILAGRO detectors.
Strain variability among Kaposi sarcoma-associated herpesvirus (human herpesvirus 8) genomes: evidence that a large cohort of United States AIDS patients may have been infected by a single common isolate.

Previous analysis of the majority of Kaposi's sarcoma (KS) tumors, in both AIDS and non-AIDS populations, has revealed the consistent presence of two small subsegments (open reading frame 25/26 [ORF25/26] and ORF75) of a novel human gamma class herpesvirus genome referred to as KSHV or HHV-8. We have carried out DNA sequence comparisons with DNAs encompassing a total of 2,500 bp each over three separate PCR-amplified fragments from KS lesions and body cavity-based lymphoma (BCBL) samples from 12 distinct patients, including four African and two classical or endemic non-AIDS KS samples. The results revealed differences at 37 of 2,500 nucleotide positions (i.e., 1.5% overall variation). However, the 12 HHV-8 genomes examined fell into three distinct but very narrow subgroupings (A, B, and C strains). All A strain isolates differed from B strain isolates at 16 positions, but of the eight U.S. samples tested, six were A strains, and these differed at no more than two positions among them. Similarly, three of the four African samples were B strains, which differed from each other at only one position. The two C strain genomes also displayed only one nucleotide variation, but they differed from all A strains at 26 positions and from all B strains at 20 positions. One C strain genome was present in all six independent lesions from an AIDS KS patient with disseminated disease, and the other represented a mosaic A/C recombinant genome from the HBL6 cell line derived from a BCBL tumor. Evaluation of previous data suggests that B and C strains may predominate in Africa and that A strains predominate in classical Mediterranean samples. Although both B and C strains are represented in U.S. AIDS patients, the majority (70 to 80%) of samples from the mid-East Coast region at least appear to be virtually identical, supporting the concept that they may all derive from the spread during the AIDS epidemic of a single recently transmitted infectious agent.
Studies on Adaptation to Information Systems: Multiple Roles and Coping Strategies

L’adaptation individuelle aux technologies de l’information (TI) a recu relativement peu d’attention dans la recherche en systemes d’information (SI). Afin de contribuer a une meilleure comprehension des problematiques que souleve ce concept, un format de these sur travaux est adopte. L’objectif est d’analyser des aspects distincts de l’interaction des utilisateurs avec les TI en lien avec la notion d’adaptation. Par consequent, afin de mieux comprendre comment les utilisateurs de TI s'adaptent a ces dernieres, cette etude examine (1) l’interaction d’utilisateurs avec une TI qui leur fournit differentes quantites d’information, en lien avec le succes de cette TI (DeLone et McLean 1992) (2) l’influence des valeurs culturelles epousees (Srite et Karahanna 2006) d'individualisme-collectivisme et d’evitement de l’incertitude sur les strategies d’adaptation et de coping des individus lors de l’implementation d’une TI disruptive, (3) et, partant d’une conceptualisation basee sur les etudes d’Emirbayer et Mische (1998) et Crozier et Friedberg (1977), les actions prises par des cadres intermediaires lors de l’integration d’une TI disruptive dans les unites locales d’une administration publique. Pour repondre aux questions de recherche qui sont posees, ces etudes adoptent des methodologies quantitatives experimentales (etudes 1 et 2) et qualitative (etude 3) et entendent contribuer a ameliorer notre comprehension des reponses des individus aux changements lies a l’introduction des TI.
A Science Superior to Music: Joseph Sauveur and the Estrangement between Music and Acoustics

The scientific revolution saw a shift from the natural philosophy of music to the science of acoustics. Joseph Sauveur (1653–1716), an early pioneer in acoustics, determined that science as understood in the eighteenth century could not address the fundamental problems of music, particularly the problem of consonance. Building on Descartes, Mersenne, and Huygens especially, Sauveur drew a sharp divide between sound and music, recognizing the former as a physical phenomenon obeying mechanical and mathematical principles and the latter as an inescapably subjective and unquantifiable perception. While acoustics grew prominent in the Academie des sciences, music largely fell out of the scientific discourse, becoming primarily practiced art rather than natural philosophy. This study illuminates what was considered proper science at the dawn of the Enlightenment and why one particular branch of natural philosophy—music—did not make the cut.
Interaction of CRF and Kappa Opioid Systems on GABAergic Neurotransmission in the Mouse Central Amygdala

The corticotropin-releasing factor (CRF) and kappa-opioid receptor (KOR) systems are both implicated in stress-related behaviors and drug dependence. Although previous studies suggest that antagonism of each system blocks aspects of experimental models of drug dependence, the possible interaction between these systems at the neuronal level has not been completely examined. We used an in vitro brain slice preparation to investigate the interaction of these two peptide systems on inhibitory neurotransmission in the central nucleus of the amygdala (CeA). Application of exogenous CRF increased the mean frequency of GABAergic miniature inhibitory postsynaptic currents (mIPSC) by 20.2%, suggesting an increase in presynaptic GABA release. Although the pharmacological blockade of KORs by norBNI alone did not significantly affect mIPSC frequency, it significantly enhanced the effect of CRF (by 43.9%, P = 0.02). Similarly, the CRF effects in slices from KOR knockout (KO) mice (84.0% increase) were significantly greater than in wild-type (WT) mice (24.6%, P = 0.01), although there was no significant difference in baseline mIPSC frequency between slices from KOR KO and WT mice. The increase in CRF action in the presence of norBNI was abolished by a CRF-1 receptor antagonist but was unaffected by a CRF-2 receptor antagonist. We hypothesize that CRF facilitates the release of an endogenous ligand for KORs and that subsequent activation of KOR receptors modulates presynaptic effects of CRF in CeA. These results suggest that potential pharmacotherapies aimed at neurobehavioral and addictive disorders may need to involve both the KOR/dynorphin and the CRF systems in CeA.
Identification for mar mutants among quinolone-resistant clinical isolates of Escherichia coli.

Quinolone-resistant clinical Escherichia coli isolates were examined for mutations in the marRAB operon of the multiple antibiotic resistance (mar) locus. Among 23 strains evaluated, 8 were chosen for further study: 3 that showed relatively high levels of uninduced, i.e., constitutive, expression of the operon and 5 with variable responses to induction by salicylate or tetracyclines. The marR genes, specifying the repressor of the operon, cloned from the three strains constitutively expressing the operon did not reduce the level of expression of beta-galactosidase from a marO::lacZ transcriptional fusion and were therefore mutant; however, marR genes cloned from the five other clinical strains repressed LacZ expression and were wild type. All three mutant marR genes contained more than one mutation: a deletion and a point mutation. Inactivation of the mar locus in the three known marR mutant strains with a kanamycin resistance cassette introduced by homologous recombination reduced resistance to quinolones and multiple antibiotics. These findings indicate that mar operon mutations exist in quinolone-resistant clinical E. coli isolates and contribute to quinolone and multidrug resistance.
Psychological distress following marital separation interacts with a polymorphism in the serotonin transporter gene to predict cardiac vagal control in the laboratory.

Marital separation is linked to negative mental and physical health; however, the strength of this link may vary across people. This study examined changes in respiratory sinus arrhythmia (RSA), used to assess cardiac vagal control, in recently separated adults (N = 79; M time since separation = 3.5 months). When reflecting on the separation, self-reported psychological distress following the separation interacted with a polymorphism in the serotonin transporter gene (5-HTTLPR) and a relevant single nucleotide polymorphism (SNP), rs25531, to predict RSA. Among people reporting emotional difficulties after the separation, those who were homozygous for the short allele had lower RSA levels while reflecting on their relationship than other genotypes. The findings, although limited by the relatively small sample size, are discussed in terms of how higher-sensitivity genotypes may interact with psychological responses to stress to alter physiology.
Establishment and Vertical Passage of Enterobacter (Pantoea) agglomerans and Klebsiella pneumoniae through All Life Stages of the Mediterranean Fruit Fly (Diptera: Tephritidae)

ABSTRACT We investigated the fate of ingested Enterobacter (Pantoea) agglomerans and Klebsiella pneumoniae within adult Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), in a mass rearing facility. This examination revealed the establishment of both bacterial strains as biofilms within the adult intestines, on the apical end of developing and developed eggs, and throughout all subsequent life stages. The bacteria were detected in adults through two generations. Irradiation treatment for the sterile insect technique did not disrupt the vertical transmission of E. (P.) agglomerans or K. pneumoniae. This is the first demonstration of maternal spread of Enterobacter/ Pantoea spp. and Klebsiella spp. through populations of C. capitata. A mixed pattern of vertical and horizontal transmission of symbionts associated with tephritids may be one explanation for the difficulty in defining the symbiotic associations of tephritids.
Histochemical Observations of Porcine Muscle as Related to Lipid Accumulation

SUMMARY —Four porcine muscle fiber types were determined on the basis of histochemical tests. Lightweight boars had a significantly higher percentage of β-hydroxybutyric-dehydro-genase-positive fibers in the longissimus dorsi than did gilts. Heavyweight boars had significtanly more esterase-positive fibers in all muscles sampled (except gluteus medius) and significantly more β-hydroxybutyric-dehydrogenase-positive fibers in the longissimus dorsi than either barrows or gilts. The number of esterase-positive fibers in all four muscles from boars tended to be higher in the heavyweight than in the lightweight group, with the difference being significant for the dark biceps femoris. The trend between weight groups was opposite for all muscles from barrows and gilts. The quantity of intramuscular lipid in the longissimus dorsi increased with slaughter weight and tended to be lowest in the boars. It was postulated that the tendency for a greater accumulation of intramuscular lipid in the longissimus dorsi muscle of barrows and gilts than in boars could be attributed partially to the smaller percentage of fibers positive for enzymes (esterase and β-hydroxybutyric dehydrogenase) necessary in removing lipid from muscle. Differences were noted between light and dark muscles in the distribution and size of blood vessels.
Inhibition of flowering and reproductive success in spreading dogbane (Apocynum androsaemifolium) by exposure to ambient ozone

Ground-level ozone continues to be a cause for concern in terrestrial ecosystems in the northeastern United States and Canada. Spreading dogbane (Apocynum androsaemifolium L.) is one of many indigenous herbaceous plant species exhibiting foliar injury that are commonly monitored in ecosystem assessment programs. Details about possible effects of ambient ozone on reproductive components of these species are lacking. For 103 days, from 31 May to 10 September, A. androsaemifolium plants were grown in open-top chambers in either carbon-filtered air (CF), non-filtered air (NF) (approximately 1xambient), or chamberless ambient air plots (AA). Aspects of sexual reproduction were measured to determine whether impairment occurs in polluted air. Additionally, the ozone protectant chemical ethylenediurea (EDU) was applied to foliage to determine its effect on foliar injury. By the end of the experiment visible foliar injury was absent in CF air and nominal in the NF and AA treatments. Plants grown in CF-chamber air produced significantly more flowers and fruits than those grown in either NF-chamber air or AA plots. Flowers produced by plants grown in CF air also survived to mature fruits at a rate 1.7x greater than plants in NF air and 1.5x greater than plants in AA plots. We were unable to conclude whether EDU protected plants from foliar ozone injury due to the general lack of foliar injury in ozone-exposed plants. The results demonstrate that foliar injury is not necessarily required to elicit negative effects on sexual reproduction in A. androsaemifolium. Implications for the population biology of A. androsaemifolium related to adverse effects of chronic ozone exposure on sexual reproduction are discussed.
Biological Diversity of Prokaryotic Type IV Secretion Systems

Type IV secretion systems (T4SS) translocate DNA and protein substrates across prokaryotic cell envelopes generally by a mechanism requiring direct contact with a target cell. Three types of T4SS have been described: (i) conjugation systems, operationally defined as machines that translocate DNA substrates intercellularly by a contact-dependent process; (ii) effector translocator systems, functioning to deliver proteins or other macromolecules to eukaryotic target cells; and (iii) DNA release/uptake systems, which translocate DNA to or from the extracellular milieu. Studies of a few paradigmatic systems, notably the conjugation systems of plasmids F, R388, RP4, and pKM101 and the Agrobacterium tumefaciens VirB/VirD4 system, have supplied important insights into the structure, function, and mechanism of action of type IV secretion machines. Information on these systems is updated, with emphasis on recent exciting structural advances. An underappreciated feature of T4SS, most notably of the conjugation subfamily, is that they are widely distributed among many species of gram-negative and -positive bacteria, wall-less bacteria, and the Archaea . Conjugation-mediated lateral gene transfer has shaped the genomes of most if not all prokaryotes over evolutionary time and also contributed in the short term to the dissemination of antibiotic resistance and other virulence traits among medically important pathogens. How have these machines adapted to function across envelopes of distantly related microorganisms? A survey of T4SS functioning in phylogenetically diverse species highlights the biological complexity of these translocation systems and identifies common mechanistic themes as well as novel adaptations for specialized purposes relating to the modulation of the donor-target cell interaction.
Equivalence of planar dynamical and differential systems

where x is a 2-vector, f(x) is homogeneous of degree N 3 1, g(x) is o (11 x 11”) for sufficiently small I] x I), and the usual existence and uniqueness properties hold for the solutions of each system close enough to the origin. The origin is assumed to be an isolated critical point of each system.A familiar problem is that of determining the local behavior of trajectories of system( 1) neartheorigin [2]. In this paper it is shown that under certain assumptions on f this behavior is qualitatively the same as that of the trajectories of (2), the system of first approximation. In particular, it is shown (Theorem 5) that there is a homeomorphism of a neighborhood of the origin onto another neighborhood of the origin which maps arcs of trajectories of system (1) onto arcs of trajectories of system (2). Two such systems are said to be locally trajectory equivalent or locally integral equivalent at the origin. The analysis rests upon two theorems, one by Forster [I], the other by Nemytski [4]. Forster’s theorem, stated in full in Section 3, resembles in spirit our main result in that it also relates the behavior of the trajectories of (1) to that of the trajectories of (2). H owever, trajectory equivalence is not proven-only that for each trajectory of (2) with a specified type of behavior near the origin there is a trajectory of (1) which behaves similarly near the origin.