cssi/SciSciGPT-SciSciNet huggingface dataset:
FPGA-based satisfiability filters for deep packet inspection

Satisfiability (SAT) filters have been recently proposed as a fast and storage-efficient way of implementing set membership operations. In this paper we discuss the application of the random SAT filters with k hash functions (k-SAT filters), for detecting the potential presence of known malicious signatures (byte patterns) in packet payloads to prevent cyber attacks. We developed and verified the operation of a FPGA-based 3-SAT filter with 3 hash functions per signature. The hash functions are implemented with bit stream processing circuits using the CRC-32 polynomial. The 3-SAT filter with 1,024 variables has a single-instance architecture with 64 solutions for a set of 3,360 input test patterns extracted from the content fields of the known malicious signatures in the Snort intrusion detection system database. During a filter construction phase, the 64 “good” solutions with the maximum Hamming distance between them have been selected among the 8,000 solutions found by a SAT solver. A Digilent Arty A7 with an Artix-7 FPGA was used to implement the filter design. The complete FPGA filter system operates at a 200 MHz clock rate and uses 720 Kbit of BRAM, 17,606 LUTs, and 20,296 flip-flops. The experimentally observed false positive rate for 50,000 randomly-generated signatures of different lengths was ∼1.6%. The 3-SAT FPGA design can be used to work with any set of signatures of interest with no need for changing and re-synthesizing VHDL code and reprogramming the entire FPGA. The results of this project allow for better understanding and planning of our next steps in the work on k-SAT filter applications for deep packet inspection.
2D-PCA Based Tensor Level Set Framework for Vertebral Body Segmentation

In this paper, a novel statistical shape modeling method is developed for the vertebral body (VB) segmentation framework. Two-dimensional principal component analysis (2D-PCA) technique is exploited to extract the shape prior. The obtained shape model is then embedded into the image domain to develop a new shape-based segmentation approach. Our framework consists of four main steps: (1) shape model construction using 2D-PCA, (2) the detection of the VB region using the Matched filter, (3) initial segmentation using a new region-based tensor level set model, and (4) registration of the shape priors and initially segmented region to obtain the final segmentation. The proposed method is validated on a Phantom as well as clinical CT images with various Gaussian noise levels. The experimental results show that the noise immunity and the segmentation accuracy of our framework are much higher than scalar level sets approaches. Additionally, the construction of the shape model using 2D-PCA is computationally more efficient than PCA.
Germinal center formation in response to skin grafted across weak and strong histocompatibility (H2) barriers.

At the Third International Congress on Germinal Centers (1,2), we reported that germinal centers were found in lymphoid tissues as early as 3 hours after stimulation by a variety of antigens including: Gross passage A virus, Brucella abortus, bovine serum albumin, and endotoxin. As a correlate to this study, we have begun to analyze the interrelationship between germinal center formation and cellular immunity.
Measurement of Material Properties for Early Detection of Fatigue Damage in Highway Bridge Steels

A recent workshop sponsored by the Federal Highway Administration (FHWA) into research needs for structures concluded that fatigue cracking is the most critical problem for the near future (FHWA, 1992). As a result, a major research thrust has concerned NDT methods to detect fatigue cracks. However, it would be extremely desirable to identify steel that is a high risk for cracking before the cracks themselves appear. A related problem is that fatigue crack prediction is based on the knowledge of the number of fatigue cracks that the steel has experienced. However, for most existing bridges, a complete fatigue cycle history is not available. Consequently there is a need for nondestructive methods that can characterize the fatigue state of steel.
The Importance of Transient Effects Resulting from Dislocation Transport of Hydrogen

A number of authors have recently considered whether or not dissolved hydrogen, when associated with mobile dislocations, either as a Cottrell atmosphere or as a dislocation core population, can be transported to local imhomogeneities (denoted as traps) in the lattice or grain boundary.1–3 These considerations have focused on the ability of these moving hydrogen sources4 to provide a mechanism for either or both local enrichment, or pressurization resulting from molecular hydrogen formation,5–9 in excess of the amount predicted from thermodynamic equilibrium of the internal hydrogen with the external fugacity. Because of the potential importance of such processes to hydrogen embrittlement, and because much of the ensuing debate has become enmeshed in justifying the validity of the details of a particular theoretical approach, we are concerned that the broader, more important issues have been neglected. Namely, are there materials, or variable ranges in a given material, where dissolved hydrogen can interact with mobile dislocations, can be then transported to local heterogeneities, and be deposited to enrich the local non-equilibrium hydrogen concentration, and possibly recombine to molecular hydrogen, with an associated large volume change and pressurization? Further, can such processes provide an accelerating step for the occurrence or severity of hydrogen embrittlement? We believe that the answer to both queries is yes, but only for very specific conditions, a point emphasized previously.1,3,8
ConfChem Conference on Mathematics in Undergraduate Chemistry Instruction: Estimation—An Empowering Skill for Students in Chemistry and Chemical Engineering

Today’s students have always used calculators to compute answers to problems, and as a result, they have a poor sense of the expected size of a physical quantity and cannot tell if their computed value is realistic or unrealistic. Students place great faith in the correctness of calculators, but they fail to acknowledge their mistakes in typing numerical values or in entering mathematical operations. These factors together not only contribute to poorer grades on exams and problem sets in their coursework, but also lead to embarrassing mistakes on group projects and in the professional workplace. The anodyne to this is a workshop approach to developing estimation skills. This report summarizes paper 1 of the 8 invited papers to the ConfChem online conference held from October 23 to November 27, 2017, and hosted by the ACS DivCHED Committee on Computers in Chemical Education (CCCE).
Bots in Nets: Empirical Comparative Analysis of Bot Evidence in Social Networks

The emergence of social bots within online social networks (OSNs) to diffuse information at scale has given rise to many efforts to detect them. While methodologies employed to detect the evolving sophistication of bots continue to improve, much work can be done to characterize the impact of bots on communication networks. In this study, we present a framework to describe the pervasiveness and relative importance of participants recognized as bots in various OSN conversations. Specifically, we harvested over 30 million tweets from three major global events in 2016 (the U.S. Presidential Election, the Ukrainian Conflict and Turkish Political Censorship) and compared the conversational patterns of bots and humans within each event. We further examined the social network structure of each conversation to determine if bots exhibited any particular network influence, while also determining bot participation in key emergent network communities. The results showed that although participants recognized as social bots comprised only 0.28% of all OSN users in this study, they accounted for a significantly large portion of prominent centrality rankings across the three conversations. This includes the identification of individual bots as top-10 influencer nodes out of a total corpus consisting of more than 2.8 million nodes.
LGI1 Limbic Encephalitis after Interleukin-2 Therapy (S50.005)

Objective: N/A Background: Limbic encephalitis is a well-described paraneoplastic disorder which typically presents with memory loss, seizures, and an emotional disturbance1. Design/Methods: We present a case of limbic encephalitis in a patient with metastatic renal cell carcinoma. Results: Our patient, who was diagnosed with metastatic cancer approximately two years prior to presentation with limbic encephalitis, had recently undergone treatment with interleukin 2 (IL-2). He presented with memory loss, behavioral changes, and generalized seizures. Evaluation with MRI brain with and without contrast demonstrated T2/FLAIR hyperintensity in both mesial temporal lobes, consistent with limbic encephalitis. Serum paraneoplastic panel revealed anti-LGI1 antibodies. He was treated with immunotherapy including high-dose intravenous methylprednisolone, IVIG, and rituximab. He was also started on antiseizure medications. His seizures were well–controlled, and his memory began to improve by the end of his hospitalization. However, his mood disturbances, including agitation and depression, persisted beyond his hospitalization. Conclusions: This case highlights the occurrence of limbic encephalitis with clear temporal relation to treatment with IL-2. Although limbic encephalitis has been clearly described in the literature to have an association with both metastatic renal cell carcinoma and anti-LGI1 antibodies2,3,4, this case is unique in that limbic encephalitis appears to have been triggered by his IL-2 treatment. IL-2 is a common treatment for immunogenic cancers, including renal cell carcinoma5. Common side effects of IL-2 include hypotension, renal and/or hepatic impairment, and thrombocytopenia6. An autoimmune reaction such as the one in our case has not previously been described with IL-2. We propose that the IL-2 therapy creates a pro-inflammatory state in a patient already at risk of limbic encephalitis and LGI1 encephalopathy, leading to a potentially devastating complication of this therapy in patients with metastatic renal cell carcinoma. Thus, patients undergoing treatment with IL-2 should be extensively counseled about the risks prior to initiation of this therapy. Study Supported by: Disclosure: Dr. Beaver has nothing to disclose. Dr. Burbank has nothing to disclose. Dr. Tharp has nothing to disclose. Dr. Szewka has nothing to disclose.
Chemical disorder and spin-liquid-like magnetism in the van der Waals layered 5 d transition metal halide Os 0.55 Cl 2

Single crystals of the van der Waals layered $5d$ transition-metal compound ${\mathrm{Os}}_{0.55}{\mathrm{Cl}}_{2}$ were grown and characterized by x-ray diffraction, magnetization and heat-capacity measurements, and atomic resolution electron microscopy. The crystals are stable in air and easily cleaved. The structure is derived from the ${\mathrm{CdCl}}_{2}$ structure type, with triangular layers of transition metal sites coordinated by edge-sharing octahedra of Cl and separated by a van der Waals gap. On average, only 55% of the metal sites are occupied by Os, and evidence for short- and long-ranged vacancy orders is observed by diffraction and real-space imaging. Magnetization data indicate magnetocrystalline anisotropy due to spin-orbit coupling, antiferromagnetic correlations, and no sign of magnetic order or spin freezing down to 0.4 K. Heat-capacity measurements in applied magnetic fields show only a broad, field-dependent anomaly. The magnetic susceptibility and heat capacity obey power laws at low temperature and low field with exponents close to 0.5. The power law behaviors of the low-temperature heat capacity and magnetic susceptibility suggest gapless magnetic fluctuations prevent spin freezing or ordering in ${\mathrm{Os}}_{0.55}{\mathrm{Cl}}_{2}$. Divergence of the magnetic Gruneisen parameter indicates nearness to a magnetic quantum critical point. Similarities to behaviors of spin-liquid materials are noted, and in total the results suggest ${\mathrm{Os}}_{0.55}{\mathrm{Cl}}_{2}$ may be an example of a quantum spin liquid in the limit of strong chemical disorder.
A Microfluidic Device to Enhance Viral Transduction Efficiency During Manufacture of Engineered Cellular Therapies

The development and approval of engineered cellular therapies are revolutionizing approaches to treatment of diseases. However, these life-saving therapies require extensive use of inefficient bioprocessing equipment and specialized reagents that can drive up the price of treatment. Integration of new genetic material into the target cells, such as viral transduction, is one of the most costly and labor-intensive steps in the production of cellular therapies. Approaches to reducing the costs associated with gene delivery have been developed using microfluidic devices to increase overall efficiency. However, these microfluidic approaches either require large quantities of virus or pre-concentration of cells with high-titer viral particles. Here, we describe the development of a microfluidic transduction device (MTD) that combines microfluidic spatial confinement with advective flow through a membrane to efficiently colocalize target cells and virus particles. We demonstrate that the MTD can improve the efficiency of lentiviral transduction for both T-cell and hematopoietic stem-cell (HSC) targets by greater than two fold relative to static controls. Furthermore, transduction saturation in the MTD is reached with only half the virus required to reach saturation under static conditions. Moreover, we show that MTD transduction does not adversely affect cell viability or expansion potential.
Enhanced Subwavelength Coupling and Nanofocusing with Fiber-Plasmonic Hybrid Probe

Metallic nanowires supporting surface plasmon polaritons can localize optical fields at nanoscale for near-field imaging. In this paper, we propose a photonic-plasmonic probe for nanoscale light confinement. The linearly polarized fiber mode is asymmetrically coupled to radial plasmons to create hot-spot at the tip apex.
“She is Like a Sister to Me.” Gender-Affirming Services and Relationships are Key to the Implementation of HIV Care Engagement Interventions with Transgender Women of Color

We present findings from qualitative interviews (N = 67) with 36 staff and 31 participants of nine distinct individual and/or group level interventions to engage transgender women of color (TWOC) in HIV care in the U.S. We examine the commonalities amongst the intervention services (addressing unmet basic needs, facilitating engagement in HIV care, health system navigation, improving health literacy, emotional support), and the relationships formed during implementation of the interventions (between interventionists and participants, among participants in intervention groups, between participants and peers in the community). Interventionists, often TWOC themselves, who provided these services developed caring relationships, promoted personal empowerment, and became role models for participants and the community. Intervention groups engaged participants to reinforce the importance of health and HIV care and provided mutual support. Gender affirming services and caring relationships may be two key characteristics of interventions that address individual and structural-level barriers to engage TWOC in HIV care.
On calibrating a microsimulation of patient movement through a healthcare network

Hospital admission and discharge dynamics facilitate pathogen transmission among individuals in communities, hospitals, nursing homes, and other healthcare facilities. We developed a microsimulation to simulate this movement, as patients are at increased risk for healthcare-associated infections, antibiotic exposure, and other health complications while admitted to healthcare facilities. Patients can also serve as a source of infection throughout the healthcare network as they move locations. This microsimulation is a base model that can be enhanced with various disease-specific agent-based health modules. We calibrated the model to simulate patient movement in North Carolina, where over 1 million hospital admissions occur annually. Each patient originated from a unique starting location and eventually transferred to another healthcare facility or returned home. Here, we describe our calibration efforts to ensure an accurate patient flow and discuss the necessary steps to replicate this model for other healthcare networks.
Effects of Housing System on Dairy Heifer Replacement Cost from Birth to Calving: Evaluating Costs of Confinement, Dry-Lot, and Pasture-Based Systems and Their Impact on Total Rearing Investment

Replacement heifer rearing is critical for the future of dairy operations, to improve genetic merit and maintain herd size. A myriad of options exist on how to manage, feed, and ultimately raise replacement heifers. Pasture is perceived to offer optimal welfare and an economical housing system for replacement animals, but confinement systems are gaining popularity. This study investigates the costs associated with replacement heifer management decisions from birth to calving, considering the factors of housing systems, labor, feed, and health. The objective of this study was to develop an economic model to determine the cost of raising a replacement heifer managed in confinement, dry-lot, and pasture-based scenarios post-weaning. We accounted for variation in feed, labor, and health inputs and quantified the impact of these individual management decisions. An economic simulation with 10,000 iterations were completed for each situation using @Risk and PrecisionTree add-ons (Palisade Corporation, Ithaca, NY) where health incidence, commodity prices, and management variables were made stochastic. Published literature or sample farm data created parameters used in Pert distributions. Costs and biological responses were reflective of published surveys, literature, and market conditions. Management decision inputs had 3 main factors: housing type, ration composition, and labor utilization. Housing systems were calculated separately for confinement, dry-lot, and pasture scenarios. The mean total cost (min, max) to raise a replacement heifer from birth to calving, assuming the same pre-weaning strategy of group housing with an automatic calf feeder, was found to be $1,919.02 ($1,777.25, $2,100.57), $1,593.57 ($1,490.30, $1,737.26), and $1,335.84 ($1,266.69, $1,423.94) for confinement, dry-lot, and pasture, respectively. Total housing cost per replacement heifer was $423.05, $117.96, and $207.96 for confinement, dry-lot, and pasture management systems, respectively. When compared to total cost, housing contributed 21% for confinement, 7% for dry-lot, and 15% for pasture. Upon analysis of all scenarios, utilizing pasture to raise heifers resulted in a lower overall cost when compared to confinement housing options. Percentage breakdowns of feed, labor, housing, and fixed and variable costs provided more information on efficiency rather than total cost, which makes each situation different in relation to on-farm cost. This cost analysis is critical to assisting farms in making decisions in the utilization of their resources for replacement dairy heifers.
Prediction of adolescent pelvis development using femoral head and acetabulum growth in a longitudinal radiographic study.

INTRODUCTION Adolescent total hip arthroplasty (THA) is guarded partially due unclarity as to when pediatric hip joints reach full development. This study sought to identify when maximum acetabular and femoral head diameters are achieved with relation to chronological and skeletal age. MATERIALS AND METHODS Consecutive femoral head and acetabular diameters were measured in a random sample of 54 female and 78 male subjects, which were queried from a historical collection of annual radiographs of children. Femoral head and triradiate physeal plates were scored according to Oxford bone parameters. RESULTS At 14 years females had femoral diameters of 4.16 +/- 0.23 cm and acetabular diameters of 5.15 +/- 0.30 cm. At 16 years males had femoral diameters of 4.85 +/- 0.30 cm and acetabular diameters of 5.90 +/- 0.35 cm. In the year following maximal femoral Oxford scores, no significant change was seen in femur and acetabulum diameters in females and in femur diameters in males. In the year following maximal acetabular Oxford scores, there was a significant increase in both femur and acetabulum diameters in both females and males. CONCLUSIONS Females on average reach maximum pelvis maturity at 14 years and males reach maximum pelvis maturity at 16 years. A closed femoral head was found to be a good marker of full hip growth, while a closed triradiate was not. This study provides anatomical data for surgeons to consider in assessing risk factors of THA failure in adolescents.
FinTech Marketplace Lending, Default Risk, and the Business Cycle

This paper explores default in the FinTech marketplace lending market using a dataset of both extensive credit and soft information for borrowers from the largest marketplace lender in the United States. I find that both macro and regional economic conditions play a role in consumer default and should be taken into consideration when assessing credit risk. I show that lenders operating in this market increasingly focus on subprime borrowers, whose default rates are more sensitive to macro and regional economic conditions than those of prime borrowers. Based on estimates from a duration model, I provide counterfactual analyses of what default rates and the associated total losses would look like in different economic scenarios. In the case of a recession, the losses would be 37 percent higher than in the case of an expansion. For the same volume of loans in the recession, doubling the subprime share would lead to an additional 7.5 percent increase in losses.
Thrombotic Microangiopathy in a Patient With COVID-19 Infection and Metastatic Cholangiocarcinoma

This is a case report of a 63-year-old African American female with a past medical history most significant for metastatic cholangiocarcinoma that presented for evaluation of persistent shortness of breath. Initial workup was remarkable for refractory anemia, moderate schistocytes on peripheral smear and lab work suggestive of a hemolytic anemia. Due to concern for thrombotic thrombocytopenic purpura (TTP), she subsequently underwent several rounds of plasma exchange without significant improvement. Secondary to progressive renal failure, patient eventually had a renal biopsy with findings remarkable for thrombotic microangiopathy (TMA). Simultaneously, patient was also diagnosed with coronavirus disease 2019 (COVID-19) infection. After a few weeks of supportive care, she was stable for discharge. Unfortunately, she did become dialysis dependent. Prior to hospital admission, she was being treated for metastatic cholangiocarcinoma and had received chemotherapy with gemcitabine. Her last chemotherapy session was approximately 3 weeks prior to her first hospitalization. Furthermore, although her hemolytic work did suggest TMA, it was not consistent with the diagnosis of TTP. She was transferred to a tertiary care center where hemolytic labs were trended, and supportive care was maximized. In light of the current COVID-19 pandemic, it is crucial to further investigate the pathophysiology of TMA in patients with active malignancies and COVID-19 infections. To our knowledge, this is the first case of TMA in a patient with both metastatic cholangiocarcinoma and COVID-19 infection.
The Freedom-based Critique of Well-Being’s Exclusive Moral Claim

Amartya Sen has suggested that the moral significance of freedom undermines the view that well-being alone possesses fundamental moral worth. Sen’s efforts to establish this claim, however, seem to...
Different Roots, Different Fruits: Gender-Based Differences in Cultural Narratives about Perceived Discrimination Produce Divergent Psychological Consequences

We examine whether narratives about, and the psychological consequences of, perceived gender discrimination differ between women and men. We argue that women and men have different dominant narrati...
Economic incentive mechanisms for user-contributed wireless networks

User-contributed wireless networks are formed by wireless devices that are owned by different users. They have been widely used to achieve better connectivity at places where an infrastructure is not immediately available or cannot be directly used. The functioning of the user-contributed wireless network depends on the cooperation of the nodes in the network. In civilian wireless networks, nodes often belong to different users who have their own interests and always want to maximize their benefits. Consequently, the user nodes may not want to behave cooperatively, if it does not suit their needs and interests. Like many distributed autonomous systems, user-contributed wireless networks have the common incentive problems such as the free-rider problem, where only a small portion of user nodes contribute their resources, and the adverse selection problem, where user nodes do not reveal their states truthfully. So, to ensure the functioning of user-contributed wireless networks, it is highly important to provide incentives for nodes to cooperate. Game theory is a nature tool to deal with the problem of selfish behavior. In our work, we adopt solution concepts from game theory to study important incentive problems in user-contributed wireless networks. We mainly focus on two categories of incentive problems: routing problems and spectrum sharing problems. For routing, we have done four works. First, we considered the traditional deterministic routing in user-contributed wireless ad hoc networks, and proposed a mechanism to prevent the user nodes from colluding. Second, we studied the incentive issues for opportunistic routing in user-contributed wireless mesh networks, and proposed mechanisms to stimulate nodes to truthfully reveal their link states, so that the most efficient routing decision can be reached. Third, we proposed the first bargaining-based incentive mechanism for probabilistic routing that stimulates selfish nodes to participate in message forwarding. Fourth, we proposed a strategy-proof mechanism to efficiently distribute data flows among node-disjoint paths obtained by multipath routing protocols. For spectrum sharing, we studied multi-radio multi-channel assignment problem in a single collision domain, and proposed an incentive mechanism to ensure the system converge to equilibrium, named strongly dominant strategy equilibrium. At the same time, this equilibrium state achieves optimal system throughput.
The effect of rumen-protected lysine methionine on gain and health of newly arrived calves

Abstract A study was conducted to evaluate the feeding of rumen-protected lysine methionine (Smartamine ML®, RPLM) to long-hauled calves during the receiving period. The calves (initial weight =133 kg) were fed 10 g of RPLM/d. Difference in gain occurred during the first 28 d, but the RPLM group gained faster (P
Partidos, coaliciones y el Congreso chileno en los años noventa

Prior to the military regime of 1973-1990, Chile's Congress was widely regarded as among the strongest legislatures in Latin America, largely because of the nature fits part/ system. In the wake of the transition back to democracy, the role of both Congress and the nature of the legislative perky system are open to question. This paper examines the nature oflegislative careers, the leadership of inn& tutions of Congress (committees and mesas directives), and patterns of floor voting in the Chamber of Deputies to evaluate the relative importance of Chile's traditional parties and the two new main coalitions in structuring legislative behavior. I conclude that the coalitions are more important institutional actors than has been recognized by most of the literature on the past-transition Chilean Congress.
CHIRAL LOOPS IN PI-0,ETA-0-]GAMMA-GAMMA AND ETA-ETA' MIXING

We compute the one-loop corrections to the Wess-Zumino Lagrangean governing ${\ensuremath{\pi}}^{0}$, ${\ensuremath{\eta}}_{8}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}$. The SU(3) relation between the two decay rates receives modifications of order ${m}_{K}^{2}\mathrm{ln}{m}_{K}^{2}$, as does the Gell-Mann-Okubo mass formula. A consistent picture of $\ensuremath{\eta}\ensuremath{-}{\ensuremath{\eta}}^{\ensuremath{'}}$ mixing emerges from both the two-photon widths and the mass matrix, however with a mixing angle $\ensuremath{\theta}\ensuremath{\approx}\ensuremath{-}20\ifmmode^\circ\else\textdegree\fi{}$ instead of the usual $\ensuremath{\theta}\ensuremath{\approx}\ensuremath{-}10\ifmmode^\circ\else\textdegree\fi{}$.
Note on uncertainty and socially excessive entry

It is well known that under general conditions entry into imperfectly competitive markets is usually excessive. This note explores the effects of uncertainty on this result. Specifically, a firm that incurs entry costs might fail to successfully enter a market. In this environment, it is found that the previous conditions might not hold when there is uncertainty. That is, with uncertainty entry might be socially insufficient (instead of excessive) by more than one firm.
Common Frontiers of the Exact Sciences and the Humanities

The physicist Franz Serafin Exner (1849–1926) was a prominent Austrian spokesman for the new developments that were coupled with turn-of-the-century experiments and theories related to entropy thermodynamics, the internally structured atom, quantum theory, and relativity. The Exner circle found its inspiration in the intellectual world of Ludwig Boltzmann and his teachers, colleagues, and students. Cross-discipline discussions on common and divergent frontiers of the exact sciences and the humanities meaningfully converged on the significance, comparison, and transfer of concepts such as the laws of nature, causality, probability, and chance. Oswald Spengler's Decline of the West, with its pessimistic, subjectivistic, and negative science-directed messages provided Exner with the opportunity to sharpen his support for the new scientific trends in physics – thus to champion the search for objective truth.
X-ray emission from reverse-shocked ejecta in supernova remnants

A simple physical model of the dynamics of a young supernova remnant is used to derive a straightforward kinematical description of the reverse shock. With suitable approximations, formulae can then be developed to give the X-ray emission of the reverse-shocked ejecta. The results are found to agree favorably with observations of SN1006.
On the additivity of basis set effects in some simple fluorine containing systems

The reactions F + H2 → HF + H, HF → H + F, F → F+ + e− and F + e− → F− were used as simple test cases to assess the additivity of basis set effects on reaction energetics computed at the MP4 level. The 6-31G and 6-311G basis sets were augmented with 1, 2, and 3 sets of polarization functions, higher angular momentum polarization functions, and diffuse functions (27 basis sets from 6-31Gd, p) to 6-31 ++ G(3df, 3pd) and likewise for the 6-311G series). For both series substantial nonadditivity was found between diffuse functions on the heavy atom and multiple polarization functions (e.g., 6-31 + G(3d, 3p) vs. 6-31 + G(d, p) and 6-31G(3d, 3p)). For the 6-311G series there is an extra nonadditivity between d functions on hydrogen and multiple polarization functions. Provided that these interactions are taken into account, the remaining basis set effects are additive to within ±0.5 kcal/mol for the reactions considered. Large basis set MP4 calculations can also be estimated to within ±0.5 kcal/mol using MP2 calculations, est. EMP4(6-31 ++ G(3df, 3pd)) ≈ EMP4(6-31G(d, p)) + EMP2(6-31 ++ G(3df, 3pd)) – EMP2(6-31G(d, p)) or EMP4(6-31 + G(d, p) + EMP2(6-31 ++ G(3df, 3pd)) – EMP2(6-31 + G(d, p)) and likewise for the 6-311G series.
Effects of protein-surface interactions on protein ion signals in MALDI mass spectrometry.

The influence of polymer surface−protein binding affinity on protein ion signals in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is examined. The surfaces of poly(vinylidene fluoride) and poly(ethylene terephthalate) polymer substrates are modified by pulsed rf plasma deposition of allylamine. By varying the on/off duty cycle of the pulsed rf plasma, the polymer substrate surfaces are coated with thin films having varying densities of surface amine groups. The varying surface amine density is shown to lead to systematic changes in the surface binding affinity for the 125I-radiolabeled peptides angiotensin I and porcine insulin. Unlabeled angiotensin I and porcine insulin are then deposited on the pulsed rf plasma-modified substrates and analyzed by MALDI mass spectrometry. The experimental approach involves applying the peptide to the modified polymer surface in an aqueous phosphate-buffered saline solution and allowing the peptide solution to dry completely under ambient conditio...
Determining material constants in micromorphic theory through phonon dispersion relations

This paper aims to determine the material constants for micromorphic isotropic elastic solid through the phonon dispersion relations from atomistic calculations or experimental measurements. A specialized micromorphic theory for crystal without external modes, such as covalent and ionic crystals, is introduced. The constitutive relations for cubic crystal are derived, and the phonon dispersion relations are obtained. The numerical algorithm to determine the material constants is presented. The material constants for single crystal silicon and diamond are determined and presented.
Correlation of activation sizes between lateral geniculate nucleus and primary visual cortex in humans.

It is well established that the lateral geniculate nucleus (LGN) and the primary visual cortex (V1) are retinotopically organized. This similarity is expected to reflect a correlation of activation sizes between V1 and LGN during visual stimulation. However, it is a challenge to determine this functional correlation experimentally in the human brain using most neuroimaging techniques due to their low sensitivity for detecting small LGN activation in the thalamus. The purpose of this study was to examine the functional correlation of activation sizes between LGN and V1 during fullfield and hemifield visual stimulation using a large visual field and high-resolution fMRI technique at 4 Tesla. The correlation was determined by comparing the V1 and LGN activation size ratios between the left and right hemispheres of the same subjects. The results reveal 1) a linear correlation of functional activation size ratio between LGN and V1 with a correlation coefficient of 0.96, and 2) the capability of fMRI for quantifying spatial correlation between cortical and subcortical activation. Magn Reson Med 45:202-205, 2001.
Enzymic saccharification of cellulose and cellulosic biomass of sweet potato (Ipomoea batatas L.) — two-step hydrolysis

Abstract The enzymatic hydrolysis of lignocellulosic biomass of sweet potato vines as well as microcrystalline cellulose, Sigmacell Type 20, by cellulases from Trichoderma viride is reported. Material was treated with a concentrated solution of ZnCl 2 and 0·5% hydrochloric acid and heated at 145°C for 12 min. Hydrolysis of the cellulose precipitated by acetone was 2–2·5 times greater than untreated lignocellulose and approached 64% conversion. A two-step hydrolysis of treated or untreated cellulose resulted in higher conversion of cellulose into reducing sugars. Increasing cellulase concentrations increased the conversion, but an increase in substrate concentration resulted in a decrease in cellulose conversion.
Sulforaphane enhances Nrf2 expression in prostate cancer TRAMP C1 cells through epigenetic regulation

Growing evidence suggests epigenetic alteration is involved during the development and progression of prostate cancer. Previously, we found Nrf2, a key regulator of cellular antioxidant defense systems, was silenced through epigenetic mechanism during tumorigenesis in vivo TRAMP mice and in vitro TRAMP C1 cells. Sulforaphane (SFN) in cruciferous vegetable has been demonstrated to be a potent cancer prevention agent for years. The aim of this study is to investigate the potential of SFN to restore Nrf2 expression in TRAMP C1 cells through epigenetic modifications. Bisulfite genomic sequencing results indicated that SFN treatment led to demethylation of the first 5 CpGs in the promoter region of the Nrf2 gene in TRAMP C1 cells. Using methylation DNA immunoprecipitation (MeDIP) assay, SFN significantly reduced the ratio of anti-mecyt antibody binding to the Nrf2 promoter containing the first 5 CpGs. SFN increased mRNA and protein expressions of Nrf2 and Nrf2 downstream target gene NQO-1. In addition, SFN decreased the protein levels of DNMT1 and DNMT3a. SFN treatment also attenuated the protein expression levels of HDACs 1, 4, 5, and 7 while increased the level of active chromatin marker acetyl-Histone 3 (Ac-H3). SFN treatments also increased chromatin-immunoprecipitated DNA of Nrf2 gene promoter using anti-Ac-H3 antibody. Taken together, our current study shows that SFN regulates Nrf2's CpGs demethylation and reactivation in TRAMP C1 cells, suggesting SFN may exert its chemopreventive effect in part via epigenetic modifications of Nrf2 gene with subsequent induction of its downstream anti-oxidative stress pathway.
Subject-specific Model Estimation of Cardiac Output and Blood Volume During Hemorrhage

We have developed a novel method for estimating subject-specific hemodynamics during hemorrhage. First, a mathematical model representing a closed-loop circulation and baroreceptor feedback system was parameterized to match the baseline physiology of individual experimental subjects by fitting model results to 1 min of pre-injury data. This automated parameterization process matched pre-injury measurements within 1.4 ± 1.3% SD. Tuned parameters were then used in similar open-loop models to simulate dynamics post-injury. Cardiac output (CO) estimates were obtained continuously using post-injury measurements of arterial blood pressure (ABP) and heart rate (HR) as inputs to the first open-loop model. Secondarily, total blood volume (TBV) estimates were obtained by summing the blood volumes in all the circulatory segments of a second open-loop model that used measured CO as an additional input. We validated the estimation method by comparing model CO results to flowprobe measurements in 14 pigs. Overall, CO estimates had a Bland-Altman bias of −0.30 l/min with upper and lower limits of agreement 0.80 and −1.40 l/min. The negative bias is likely due to overestimation of the peripheral resistance response to hemorrhage. There was no reference measurement of TBV; however, the estimates appeared reasonable and clearly predicted survival versus death during the post-hemorrhage period. Both open-loop models ran in real time on a computer with a 2.4 GHz processor, and their clinical applicability in emergency care scenarios is discussed.
Taking stock of cognition enhancers

An increasing number of structurally heterogeneous compounds, which may act via very different categories of neuronal mechanisms, have been proposed to facilitate attentional abilities and acquisition, storage and retrieval of information, and/or to attenuate the impairments of such cognitive functions associated with age or dementia. In this article, Martin Sarter briefly reviews the data on putative cognition enhancers and examines the possible bases for the discrepancy between preclinical predictions of efficacy and the fact that unequivocal demonstration of drug-induced cognition enhancement in humans has only rarely been reported. Previous preclinical research strategies appear to have focused on the demonstration of drug effects in a wide variety of tests of uncertain validity, rather than on determination of the specific psychological and neurobiological processes affected by putative cognition enhancers. Some criteria are proposed for evaluating the validity of preclinical tests for cognition enhancers.
Influence of Room‐Temperature Atmospheric Reaction Products on the Ductility of Sodium Chloride Single Crystals

Bend tests were made using sodium chloride single crystals which had previously been exposed to one of several atmospheres at room temperature. Crystals exposed to moist carbon dioxide showed the most consistent brittle behavior while those aged in moist air containing hydrogen chloride showed more ductile behavior. Evidence is given which indicates that hydroxide ion is needed for carbon dioxide to cause embrittlement. Furthermore, room‐temperature hydrolysis is shown by experiments in which the increase of alkalinity of finely divided sodium chloride is measured upon long exposure to moist air. These results lead to the proposal of a new mechanism to explain age embrittlement of sodium chloride crystals: sodium chloride crystals containing hydroxide ion react with carbon dioxide to become embrittled. Crystal surfaces initially free from hydroxide can become contaminated with it by reaction with water vapor of the air. Changes in ductility due to physical adsorption of carbon dioxide or hydrogen chloride were not observed.
Wage differentials across firms: an application of multilevel modelling

Multilevel modelling techniques are applied to a dataset that matches firms and workers, to pinpoint and explain contrasts among company wage policies. Results indicate that wage differences across firms are statistically significant, affecting every parameter of the pay policy (returns to schooling, tenure, experience, the penalty imposed on newly hired workers and on women). Gross labour productivity, average schooling in the firm, firm size and economic sector are relevant forces shaping the contrast between employers' pay policies. Copyright © 2000 John Wiley & Sons, Ltd.
Invariant imbedding and the reduction of boundary-value problems of thin-plate theory to Cauchy formulations

Abstract Using ideas of invariant imbedding, a classical elliptic boundary value problem, namely the biharmonic equation in a rectangular domain, is reduced to a Cauchy formulation, i.e. to an initial value problem. The theory is developed in the context of elementary thin plate theory. It is shown that a rectangular plate with three edges clamped and the fourth edge free can be completely described by a system of integrodifferential equations subject to initial values. The functions defined by these equations are intimately related to the Green's function of the plate. The Betti reciprocity relations are proved in the context of the present theory and some applications of the fundamental solution are considered. It is finally shown that the present Cauchy system can generate a variety of novel numerical schemes including those previously developed in references [4] and [5].
Association of phospholipids with bacterial ribosomes

Phospholipids were found associated with isolated ribosomes fromBacillus megaterium. The 50S subunits contained a large amount of phospholipids than 30S subunits. The larger subunits contained a different proportion of individual phospholipids from the whole cells and were enriched in cardiolipin.
Multiple functions of nucleosomes and regulatory factors in transcription

The in vivo packaging of DNA with histone proteins to form chromatin makes its transcription a difficult process. Biochemical and genetic studies are beginning to reveal mechanistic details of how transcriptional regulatory factors confront at least two hurdles created by nucleosomes, the primary structural unit of chromatin. Regulatory factors must gain access to their respective binding sites and activate the formation of transcription complexes at core promoter elements. Distinct regulatory factors may be specialized to perform these functions.
Determination of the dynamic metastable limit for α-lactose monohydrate crystallization

Abstract In lactose refining, crystal size distributions of lactose crystals can be controlled by two major kinetic steps: nucleation and growth. Nucleation is strongly related to the metastable zone width (MSZW), defined as the area between the saturation curve and labile zone. Inside the MSZW, crystal growth is fastest with least secondary nucleation. This study aimed to refine the metastable limit (ML) developed earlier for lactose crystallization, making it suitable for designing an industrial operation. The ML under continuous stirring and seeded conditions was measured experimentally. The microscopy data showed that the temperature of first nuclei detection was independent of the agitation speed. However, the spectroscopy data showed that, after the production of the first nuclei, the extent of secondary nucleation increased rapidly as the agitation speed increased. Thus, to effectively avoid secondary nucleation and promote growth, a lactose crystallization process should operate at minimal agitation rate, in the upper ML recommended in this study.
Inhibition of microsomal oxidoses from the housefly

Abstract The hydroxylation of naphthalene, O-demethylation of p-nitroanisole, and N-demethylation of N,N-dimethyl-p-nitrophenylcarbamate by housefly microsomes were inhibited by CO, sulfhydryl reagents, Cu (II), methylene dioxyphenyl compounds and β-diethylaminoethyldiphenylvaleric acid (SKF 525-A). Kinetic analysis indicates that the inhibitory properties of SKF 525-A and piperonyl butoxide are changed during the incubation period. Bovine serum albumen changes the kinetic constants in a way which suggests binding of an endogenous inhibitor(s). Patterns of inhibition indicate p-nitroanisole oxidation is effected by a system with at least one component distinct from the system which oxidizes naphthalene and N,N-dimethyl-p-nitrophenylcarbamate.
Techniques for Determining Cardiac Output in the Intensive Care Unit

To achieve the goals of resuscitation in critically ill patients, a thorough understanding of the techniques available to measure cardiac output is important. Recently the pulmonary artery catheter has fallen out of favor because of concerns of safety and a lack of efficacy. Newer less invasive techniques since have been developed and are gaining popularity. But is important to remember that the ability of these techniques to improve outcome has yet to be demonstrated, and one should apply caution in how they are used until their use in algorithmic treatment approaches have been shown to improve outcome. This article discusses the invasive and noninvasive techniques to assess cardiac output.
The use of soils lightly enriched in 15 N to screen for N 2 -fixing activity

This short communication proposes the use of soils whose organic N has been lightly enriched in15N to screen plants for N2-fixing activity. The major advantage of this approach is that it provides a reliable, integrated estimate of N2-fixation up to any point in the life cycle of the plant, while using very few plants. The feasibility of the method, from the points of view of cost and availability of suitable soils, is discussed.
A Branch-and-Cut Algorithm Without Binary Variables for Nonconvex Piecewise Linear Optimization

We give a branch-and-cut algorithm for solving linear programs (LPs) with continuous separable piecewise-linear cost functions (PLFs). Models for PLFs use continuous variables in special-ordered sets of type 2 (SOS2). Traditionally, SOS2 constraints are enforced by introducing auxiliary binary variables and other linear constraints on them. Alternatively, we can enforce SOS2 constraints by branching on them, thus dispensing with auxiliary binary variables. We explore this approach further by studying the inequality description of the convex hull of the feasible set of LPs with PLFs in the space of the continuous variables, and using the new cuts in a branch-and-cut scheme without auxiliary binary variables. We give two families of valid inequalities. The first family is obtained by lifting the convexity constraints. The second family consists of lifted cover inequalities. Finally, we report computational results that demonstrate the effectiveness of our cuts, and that branch-and-cut without auxiliary binary variables is significantly more practical than the traditional mixed-integer programming approach.