cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanisms of Intergenerational Environmental Stewardship Activated by COVID-19: Gratitude, Fairness, and Legacy Motives

The COVID-19 pandemic has caused an immense loss of human life, increased economic uncertainty, and negatively impacted individuals’ mental health and close relationships. At the same time, experts have noted a concurrent improvement in many environmental quality indicators, including significant decreases in both localized air pollution and global greenhouse gas emissions. These positive trends are due to changes in human behavior necessitated by social distancing and self-quarantining measures (e.g., reduced car and air travel). However, there is already evidence that these improvements in environmental quality are only temporary. This suggests that more intentional efforts will be necessary in order to maintain positive environmental benefits and address major environmental issues as the world gets back to some version of pre-pandemic economic and social activity. Still, our collective experience over the course of the pandemic provides clear evidence that such change is possible and on a rapid timetable. Our individual and collective responses to COVID-19 reveal that we do indeed have the ability to respond to novel societal threats in highly coordinated and effective ways, suggesting that confronting the existential threat of climate change may in fact be feasible. Here, we theorize that the COVID-19 pandemic has potentially activated and made more salient some key psychological mechanisms—including norms of fairness and reciprocity, feelings of gratitude, and consideration of personal legacies—that previous empirical work suggests can be harnessed to promote beneficent intergenerational decision-making aimed at solving the environmental challenges we and our descendants will face in the 21st century.
Contemporary Outcomes of Durable Ventricular Assist Devices in Adults with Congenital Heart Disease as a Bridge to Heart Transplantation

OBJECTIVES This study aimed to compare the clinical characteristics, risk factors, and overall survival outcomes in adults with congenital heart disease (ACHD) bridged to transplantation with a ventricular assist device (VAD) versus no-VAD. METHODS The study included 894 ACHD patients aged ≥18 years listed for primary heart transplantation between 2010 and 2019 from the United Network for Organ Sharing database. Primary outcomes were waitlist and 1-year post-transplant mortality between VAD and no-VAD ACHD patients. RESULTS Of 894 ACHD patients included in the study, 91(10.1%) had VAD support at the time of listing. Patients who needed VAD support were mostly males, heavier, and had higher pulmonary artery pressure than the no-VAD group at the listing. The overall waitlist mortality was 38% in the VAD group than 17% in the no-VAD group (p 2 mg/dl (HR 1.1; p = 0.03), creatinine >2 mg/dl (HR 1.3; p = 0.04) and ECMO at transplant (HR 1.4; p = 0.03) increased early post-transplant mortality. CONCLUSIONS The one-year post-transplant mortality rate was no different for ACHD patients that received VAD versus no-VAD. These findings suggest that a VAD should be considered an option to support ACHD patients as a bridge to heart transplantation.
Hybrid active shape and deep learning method for the accurate and robust segmentation of the intracochlear anatomy in clinical head CT and CBCT images.

Purpose: Robust and accurate segmentation methods for the intracochlear anatomy (ICA) are a critical step in the image-guided cochlear implant programming process. We have proposed an active shape model (ASM)-based method and a deep learning (DL)-based method for this task, and we have observed that the DL method tends to be more accurate than the ASM method while the ASM method tends to be more robust. Approach: We propose a DL-based U-Net-like architecture that incorporates ASM segmentation into the network. A quantitative analysis is performed on a dataset that consists of 11 cochlea specimens for which a segmentation ground truth is available. To qualitatively evaluate the robustness of the method, an experienced expert is asked to visually inspect and grade the segmentation results on a clinical dataset made of 138 image volumes acquired with conventional CT scanners and of 39 image volumes acquired with cone beam CT (CBCT) scanners. Finally, we compare training the network (1) first with the ASM results, and then fine-tuning it with the ground truth segmentation and (2) directly with the specimens with ground truth segmentation. Results: Quantitative and qualitative results show that the proposed method increases substantially the robustness of the DL method while having only a minor detrimental effect (though not significant) on its accuracy. Expert evaluation of the clinical dataset shows that by incorporating the ASM segmentation into the DL network, the proportion of good segmentation cases increases from 60/177 to 119/177 when training only with the specimens and increases from 129/177 to 151/177 when pretraining with the ASM results. Conclusions: A hybrid ASM and DL-based segmentation method is proposed to segment the ICA in CT and CBCT images. Our results show that combining DL and ASM methods leads to a solution that is both robust and accurate.
Nonviable bacterial antigens administered with IL-12 generate antigen-specific T cell responses and protective immunity against Listeria monocytogenes.

The development of effective vaccine strategies for intracellular pathogens, including bacteria, viruses, and parasites, is one of the major frontiers of scientific research. For the studies described here, the murine model of Listeria infection was used to evaluate the adjuvant effects of IL-12 when used as an immunization component. These studies revealed that typically nonimmunogenic doses of heat-killed Listeria monocytogenes, or soluble listerial Ag preparations, elicit intense Th1-type Listeria-specific T cell responses when administered i.p. along with recombinant murine IL-12. In addition to the Ag-specific production of IL-2 by CD4+ peritoneal cells that was elicited, several other correlates of protective responses were noted, including dramatic induction of CD3+ and alpha beta TCR+ cell populations in the peritoneal cavity and increased expression of class II MHC and production of IL-12 (upon in vitro restimulation) by peritoneal macrophages. Protection studies demonstrated that the T cell responses elicited by a IL-12-potentiated, heat-killed L. monocytogenes vaccine were sufficient to effectively protect mice against challenge with a large dose of virulent Listeria.
Empirical study of QS-9000 using principal components analysis and robust regression

[This abstract is based on the author's abstract.] The impact of organizational variables on operational and business performance measurements of automotive suppliers completing QS-9000 is studied. A literature review covers quality management systems, ..
The binding of a fluorescent activator 2-(N-decyl)aminonaphthalene-6-sulfonic acid to pyruvate oxidase.

Abstract E. coli pyruvate oxidase (pyruvate:ferricytochrome b 1 oxidoreductase, EC 1.2.2.2) is a peripheral membrane flavoenzyme which has been purified to homogeneity. In vivo the oxidase resides on the inner surface of the cytoplasmic membrane and is coupled to the bacterial electron transport chain. In vitro, the purified oxidase requires lipids for ful enzymatic activity. Previous studies have characterized the conformational and energetic coupling between the lipid-binding site)s) and the catalytic active site. The affinity of the enzyme for phospholipids and detergents is significantly enhanced when the flavoprotein is in the reduced form, i.e., in the presence of pyruvate and the required cofactor, thiamin pyrophosphate. The lipid-binding studies were hindered due to the complicating factor of the self-association of the substrate-reduced flavoprotein. In th is paper, fluorescence techniques are employed to measure the binding of a detergent-like activator to the oxidase. The experiments are performed at much lower protein concentrations than previously employed, so that protein aggregation is not a problem. The chromophore on the activator, 2-(N- decyl)aminonaphthalene-6-sulfonic acid is effective at quenching the pyruvate oxidase intrinsic tryptophan fluorescence. Quenching titrations are used to obtain the binding isotherm. At DNS concentrations less than 10−5 M, the results show a larger amount of DNS binding to the reduced flavoprotein than to the oxidized form of the enzyme. This is the concentration range where DNS is an effective activator of the enzyme. This represents a class of binding sites specifically found on pyruvate oxidase and not apparent in other proteins such as lysozyme or aldolase. At the DNS concentration which is optimum for activation approx. 20 molecules of DNS are bound per enzyme tetramer in the absence of the substrate. The pyruvate-reduced form of the enzyme binds about 40–50 molecules of DNS per tetramer. Qualitatively, the results are similar to what was previously found for both sodium dodecyl sulfate and cetyl trimethylammonium bromide. However, in both these cases, the amount of bound detergent was nearly an order of magnitude less than the values obtained using DNS.
Anaerobic biosynthesis of the lower ligand of vitamin B12

Vitamin B12 (cobalamin) is required by humans and other organisms for diverse metabolic processes, although only a subset of prokaryotes is capable of synthesizing B12 and other cobamide cofactors. The complete aerobic and anaerobic pathways for the de novo biosynthesis of B12 are known, with the exception of the steps leading to the anaerobic biosynthesis of the lower ligand, 5,6-dimethylbenzimidazole (DMB). Here, we report the identification and characterization of the complete pathway for anaerobic DMB biosynthesis. This pathway, identified in the obligate anaerobic bacterium Eubacterium limosum, is composed of five previously uncharacterized genes, bzaABCDE, that together direct DMB production when expressed in anaerobically cultured Escherichia coli. Expression of different combinations of the bza genes revealed that 5-hydroxybenzimidazole, 5-methoxybenzimidazole, and 5-methoxy-6-methylbenzimidazole, all of which are lower ligands of cobamides produced by other organisms, are intermediates in the pathway. The bza gene content of several bacterial and archaeal genomes is consistent with experimentally determined structures of the benzimidazoles produced by these organisms, indicating that these genes can be used to predict cobamide structure. The identification of the bza genes thus represents the last remaining unknown component of the biosynthetic pathway for not only B12 itself, but also for three other cobamide lower ligands whose biosynthesis was previously unknown. Given the importance of cobamides in environmental, industrial, and human-associated microbial metabolism, the ability to predict cobamide structure may lead to an improved ability to understand and manipulate microbial metabolism.
Social entrepreneurship compared to government foreign aid

Purpose – This paper sets out to describe several contemporary models of social entrepreneurship, along with the historical context of African nations typically receiving aid. It also seeks to critique three aid‐providing sectors – i.e. charity, government, and social entrepreneurship – with benefits and to explore the limits of each. It also aims to explore the perceptions of aid recipients in an East African village to determine their views of social entrepreneurship compared with other types of foreign aid.Design/methodology/approach – Open‐ended interviews were conducted with village elders to establish an exploratory research foundation.Findings – In general, village leaders were more favorable to social entrepreneurship efforts because they offered the possibility of self‐reliance and sustainability over time. Large government foreign aid largesse rarely reached villagers, so had little effectiveness in relieving their poverty.Research limitations/implications – Several limitations are evident with ...
TRAIL contributes to the apoptotic effect of 13-cis retinoic acid in human sebaceous gland cells.

Background Isotretinoin’s (13-cis RA) full mechanism of action in treating acne is unknown. 13-cis RA induces key genes in sebocytes that are involved in apoptosis. In this study, we report that 13-cis RA up-regulates expression of Tumor necrosis factor Related Apoptosis Inducing Ligand (TRAIL) within SEB-1 sebocytes.
INTRAMOLECULAR ELECTROSTATIC INTERACTIONS ACCELERATE HYDROGEN EXCHANGE IN DIKETOPIPERAZINE RELATIVE TO 2-PIPERIDONE

1H NMR saturation transfer and T1 experiments were used to monitor the amide hydrogen exchange rates of 2,5-piperazinedione (diketopiperazine, DKP) and 2-piperidone (δ-valerolactam) in water. Speci...
Comment on the effect of reactant internal energy on spectator stripping

Abstract The internal motion of the reactant molecule is unable to account for the excess translational energy possessed by the products of simple exothermic ion-molecule reactions.
High-resolution NMR structure and backbone dynamics of the Bacillus subtilis response regulator, Spo0F: implications for phosphorylation and molecular recognition.

NMR has been employed for structural and dynamic studies of the bacterial response regulator, Spo0F. This 124-residue protein is an essential component of the sporulation phosphorelay signal transduction pathway in Bacillus subtilis. Three-dimensional 1H, 15N, and 13C experiments have been used to obtain full side chain assignments and the 1511 distance, 121 dihedral angle, and 80 hydrogen bonding restraints required for generating a family of structures (14 restraints per residue). The structures give a well-defined (α/β)5 fold for residues 4−120 with average rms deviations of 0.59 A for backbone heavy atoms and 1.02 A for all heavy atoms. Analyses of backbone 15N relaxation measurements demonstrate relative rigidity in most regions of regular secondary structure with a generalized order parameter (S2) of 0.9 ± 0.05 and a rotational correlation time (τm) of 7.0 ± 0.5 ns. Loop regions near the site of phosphorylation have higher than average rms deviation values and T1/T2 ratios suggesting significant int...
Automated scanning of 14C on polyacrylamide gel.

Abstract Cylindrical polyacrylamide gels were automatically analyzed from radioactive 14 C using a commercially available radiochromatogram scanner. This method was capable of detecting peaks of [ 14 C]protein containing 50 000–1 000 000 cpm. Under optimal conditions, gel could be scanned at a rate of 1 cm per min, allowing for analysis of 20–30 gels per day.
"Fishing" for the functional proteome.

Activity-based profiling of proteomes is a powerful strategy for identifying the functional participants in complex biological processes.
Whither Didst Thou Go? Retention, Reassignment, Migration, and Attrition of Special and General Education Teachers from a National Perspective

In view of the paucity of national data on teacher retention, transfer, and attrition in special education, and the importance of these phenomena to teacher demand and shortage, we sought to provide such data from a national probability sample of 4,798 public school teachers from the 1988–1989 Teacher Followup Survey (Faupel, Bobbitt, & Friedrichs, 1992). The analysis focused on two main teaching fields (special and general education) and various aspects of teacher turnover. Results showed higher annual turnover for special education teachers (SFTs) than for general education teachers (GETs), in terms of both attrition from public school teaching (SETs = 8%; GETs = 6%) and transfer among public schools (SETs = 13%; GETs = 7%). However, the SET-GET difference in attrition percentages was modest in absolute terms, and lower than those reported from several states. SETs and GETs who left teaching did not differ significantly in postteaching activities or plans to return to teaching. The relationships between...
Cryogenic Machining of Hard-To-Machine Material, AISI 52100: A Study of Chip Morphology and Comparison with Dry Machining

Cryogenic cooling is a new emerging cooling application in machining processes. Quantitative understanding of the effects of cryogenic cooling on the machining performance is important for continued applications. This study focuses on cryogenic machining of hard-to-machine material, AISI 52100, particularly with an analysis of cooling-induced chip morphology, chip hardness and the effect of workpiece hardness, etc., as these measures reflect the material`s thermo-mechanical behavior during the plastic deformation. AISI 52100 steel, with different initial hardness values, is selected as the work material for orthogonal cutting under dry and cryogenic cooling conditions, and the results are compared. The findings of this study show that cryogenic cooling affects the chip formation process, and the associated hardness produced on the machined surface.
Stability analysis of 4-species Aβ aggregation model: A novel approach to obtaining physically meaningful rate constants

Protein misfolding and concomitant aggregation towards amyloid formation is the underlying biochemical commonality among a wide range of human pathologies. Amyloid formation involves the conversion of proteins from their native monomeric states (intrinsically disordered or globular) to well-organized, fibrillar aggregates in a nucleation-dependent manner. Understanding the mechanism of aggregation is important not only to gain better insight into amyloid pathology but also to simulate and predict molecular pathways. One of the main impediments in doing so is the stochastic nature of interactions that impedes thorough experimental characterization and the development of meaningful insights. In this study, we have utilized a well-known intermediate state along the [email protected] peptide aggregation pathway called protofibrils as a model system to investigate the molecular mechanisms by which they form fibrils using stability and perturbation analysis. Investigation of protofibril aggregation mechanism limits both the number of species to be modeled (monomers, and protofibrils), as well as the reactions to two (elongation by monomer addition, and protofibril-protofibril lateral association). Our new model is a reduced order four species model grounded in mass action kinetics. Our prior study required 3200 reactions, which makes determining the reaction parameters prohibitively difficult. Using this model, along with a linear perturbation argument, we rigorously determine stable ranges of rate constants for the reactions and ensure they are physically meaningful. This was accomplished by finding the ranges in which the perturbations die-out in a five-parameter sweep, which includes the monomer and protofibril equilibrium concentrations and three of the rate constants. The results presented are a proof-of-concept method in determining meaningful rate constants that can be used as a bonafide way for determining accurate rate constants for other models involving complex biological reactions such as amyloid aggregation.
Fiber composite plates for strengthening bridge beams

Abstract Although the use of Glass Fiber Reinforced Plastics (GFRP) has increased significantly in recent years, its application in civil engineering has been limited at best. The high strength of GFRP and its resistance to corrosion makes it a suitable candidate in many applications where steel has been predominantly used in the past. In this study, five reinforced concrete beams were strengthened by epoxy-bonding GFRP plates along the tension flange of the beams. The load versus deflection curves to failure and the behavior of each specimen under static loading is presented. It is shown that the method presents great potential for solving some of the global problems facing the aging infrastructure.
The culture of albino tobacco protoplasts treated with polyethylene glycol to induce chloroplast incorporation

Abstract Albino leaf protoplasts of Nicotiana tabacum, cv. Turkish Samsun, were treated with 29% polyethylene glycol in the presence of Nicotiana excelsior chloroplasts to induce chloroplast uptake. The protoplasts could not be recovered from the polyethylene glycol medium by either flotation or sedimentation. They did, however, divide and grow into colonies when the polyethylene glycol was diluted to concentrations of 3.5% or less. Careful regulation of the population densities of protoplasts and chloroplasts during polyethylene glycol treatment was necessary to ensure the survival of the protoplasts. Plantlets were regenerated from callus derived from albino protoplast populations in which chloroplast incorporation was observed. While some of these plantlets were pale green, none was capable of autotrophic growth.
Statistical methods in genetic mapping.

This report describes the proceedings from the second Workshop on Statistical Methods in Genetic Mapping, held in Tarrytown, NY on November 13-15, 1995. The workshop was supported by a grant from the National Center for Human Genome Research and covered a wide variety of topics pertaining to genetic mapping methods, integration and concerns. 25 refs.
Folyl polyglutamate and folate-requiring enzymes as bacteriophage T4D baseplate structural components.

Abstract The hexagonal-shaped baseplate on the tail of Escherichia coli bacteriophage T4D has been shown to contain 5–6 molecules of an unusual form of folic acid, dihydropteroyl hexaglutamate. In addition to this viral-induced small molecule, 2 viral-induced folate-requiring enzymes, namely dihydrofolate reductase ( frd ) and thymidylate synthetase ( td ), have also been found as phage baseplate components. The pteridine portion of the folate has been located near the baseplate frd and td and all 3 components are partially covered by T4D gene product 11 (gp11) which lies largely on the distal surface of the baseplate. On the other hand, the polyglutamate portion of the baseplate folic acid lies under or near the attachment region for the long tail fibers. Recent results have shown that the baseplate frd is a component of the outer wedge-like structures of the baseplate and highly suggestive evidence has now been obtained that the td molecule is a component of the central plug of the baseplate. These findings support the hypothesis that the baseplate folate plays a unique role in linking together the baseplate wedges and central plug by binding simultaneously to the wedge frd and to the plug td . This structural role for the viral folate and folate-requiring enzymes indicates that these baseplate components are not acting primarily in their usual roles as a coenzyme or as enzymes but are participants in a unique biological assembly process. Some molecular properties of dihydropteroyl hexaglutamate are presented which bear on its binding energies as a structural linking element. Finally some speculation is offered on the abiogenic origin of pteridine compounds.
Security on the move: indirect authentication using Kerberos

Even as mobile computing and network computing are gaining momentum, Internet security is sharing the spotlight. Security and authentication on open networks is difficult even without the additional risks posed by wireless media. At the same time, the hardware and software constraints imposed by “small” mobile devices such as PDA’s and smart phones are leading to the pervasive use of application-level proxies to mediate between clients and servers. To date, less attention has been focused specifically on securing the connection between the client and an application-level proxy, independently of any particular service. We describe how to provide secure access to application-level proxied services using an indirect protocol called Charon, which leverages the strong protocol and deployed infrastructure of Kerberos IV. Charon partitions the Kerberos client functionality into a very simple client module that does little more than DES encryption, and a Unix-hosted unprivileged proxy module that runs the remainder of the Kerberos client protocol and can interoperate with other proxy code that provides application-level proxy services. The client module is extremely lightweight and amenable to implementation even on the most modest PDA-class devices. The proxy is trusted as much as any other Kerberized service, but it never learns the user’s Kerberos password or ticketgranting service session key. As a result of this partitioning, clients can continue to enjoy the benefits of proxy-mediated access in a secure way, in addition to gaining secure access to and interoperability with existing Kerberized services.
Imido Complexes Derived from the Reactions of Niobium and Tantalum Pentachlorides with Primary Amines: Relevance to the Chemical Vapor Deposition of Metal Nitride Films

Reactions of niobium and tantalum pentachlorides with tert-butylamine (≥6 equiv) in benzene afford the dimeric imido complexes [NbCl2(NtBu)(NHtBu)(NH2tBu)]2 (90%) and [TaCl2(NtBu)(NHtBu)(NH2tBu)]2 (79%). The niobium complex exists as two isomers in solution, while the tantalum complex is composed of three major isomers and at least two minor isomers. Analogous treatments with isopropylamine (≥7 equiv) give the monomeric complexes NbCl2(NiPr)(NHiPr)(NH2iPr)2 (84%) and TaCl2(NiPr)(NHiPr)(NH2iPr)2 (84%). The monomeric complexes are unaffected by treatment with excess isopropylamine, while the dimeric complexes are cleaved to the monomers MCl2(NtBu)(NHtBu)(NH2tBu)2 upon addition of excess tert-butylamine in chloroform solution. Treatment of niobium and tantalum pentachlorides with 2,6-diisopropylaniline affords insoluble precipitates of [NH3(2,6-(CH(CH3)2)2C6H3)]2[NbCl5(N(2,6-(CH(CH3)2)2C6H3))] (100%) and [NH3(2,6-(CH(CH3)2)2C6H3)]2[TaCl5(N(2,6-(CH(CH3)2)2C6H3))] (100%), which react with 4-tert-butylpyridine ...
Fatty acids and sterols of particulate matter in a brackish and seasonally anoxic coastal salt pond

Particulate matter and interfacial sediment from a seasonally anoxic coastal salt pond were analyzed for fatty acids and sterols to examine variations in organic sources, and compositional changes across the oxic-anoxic interface in the water column and at the sediment-water interface. Fatty acid distributions in suspended particles varied seasonally and as a function of depth. Fatty acids of algal origin (e.g. 16:3, 16:4, 18:3, 18:4) were abundant in particles in oxic surface waters, but these labile components were depleted in particles from the anoxic zone which instead were enriched in bacterial fatty acids (e.g. 16:1Δ9, 18:1Δ11, anteiso-C15). Sterol distributionsvaried less than fatty acid distributions and particles throughout the water column reflected an upper water algal source with little in situ alteration. There was evidence for an in situ conversion of Δ5-stenols to 5(α)H-stanols in suspended particles in the anoxic zone. Sinking particles and the interfacial sediment were compositionally similar to each other, but different from suspended particles. These data reflect differences in particle source, transport and transformation processes occuring in the water column.
Parametric stochastic convexity and concavity of stochastic processes

A collection of random variables {X(θ), θ∈Θ} is said to be parametrically stochastically increasing and convex (concave) in θ∈Θ if X(θ) is stochastically increasing in θ, and if for any increasing convex (concave) function ϕ, Eϕ(X(θ)) is increasing and convex (concave) in θ∈Θ whenever these expectations exist. In this paper a notion of directional convexity (concavity) is introduced and its stochastic analog is studied. Using the notion of stochastic directional convexity (concavity), a sufficient condition, on the transition matrix of a discrete time Markov process {Xn(θ), n=0,1,2,...}, which implies the stochastic monotonicity and convexity of {Xn(θ), θ∈Θ}, for any n, is found. Through uniformization these kinds of results extend to the continuous time case. Some illustrative applications in queueing theory, reliability theory and branching processes are given.
Garlic and associated allyl sulfur components inhibit N-methyl-N-nitrosourea induced rat mammary carcinogenesis

Our previous studies demonstrated that dietary garlic powder supplementation inhibits N-nitrosamine induced DNA alkylation in liver and mammary tissue. The present studies compared the impact of dietary supplementation with garlic powder or two garlic constituents, water-soluble S-allyl cysteine (SAC) and oil-soluble diallyl disulfide (DADS), on the incidence of mammary tumorigenesis induced by N-methyl-N-nitrosourea (MNU). Female Sprague-Dawley rats were fed semi-purified casein based diets with or without supplements of garlic powder(20g/kg), SAC (57 micromol/kg) or DADS (57 micromol/kg) for 2 weeks prior to treatment with MNU (15 mg/kg body wt). Garlic powder, SAC and DADS supplementation significantly delayed the onset of mammary tumors compared to rats receiving the unsupplemented diet. Tumor incidence 23 weeks after MNU treatment was reduced by 76, 41 and 53% in rats fed garlic, SAC and DADS, respectively, compared to controls (P<0.05). Total tumor number was reduced 81, 35 and 65% by these supplements, respectively (P<0.05). In a separate study the quantity of mammary DNA alkylation occurring 3 h after MNU treatment was reduced in rats fed garlic, SAC or DADS (P<0.05). Specifically, O(6)-methylguanine adducts were reduced by 27, 18 and 23% in rats fed supplemental garlic, SAC and DADS, respectively, compared to controls. N(7)-Methylguanine adducts decreased by 48, 22 and 21% respectively, compared to rats fed the control diet. These studies demonstrate that garlic and associated allyl sulfur components, SAC and DADS, are effective inhibitors of MNU-induced mammary carcinogenesis.
The synthesis and subcellular distribution of pyridoxal phosphate in rat and bovine retinas.

Abstract In the absence of any known studies dealing with status of vitamin B6 metabolism in mammalian retinas, the concentration of pyridoxal phosphate and the activity of its synthesizing enzyme pyridoxal kinase were determined in rat retina and bovine retina and its subcellular compartments. In bovine retina, the highest concentration of pyridoxal phosphate (148 pmol/mg protein) was present in pellet 2 fraction containing synaptosomes comparable to those isolated from brain. The second highest concentration of pyridoxal phosphate (91 pmol/mg protein) was present in pellet 1 fraction containing large synaptosomes resembling photoreceptor cell terminals. The concentrations of pyridoxal phosphate in pellets 1 and 2 fractions were approx 3- to 6-fold higher than that found in the whole retina. The concentration of pyridoxal phosphate and the activity of pyridoxal kinase in the rat retina were considerably higher than those observed in the bovine retina. In general, no apparent correlation existed between the concentrations of pyridoxal phosphate and the activities of pyridoxal kinase in bovine retina and its subcellular compartments.
Differential accumulation of radiopaque contrast material in acute myocardial infarction.

Abstract The differential accumulation of radiographic contrast materials in ischemically damaged and normal myocardium was assessed with direct measurement (fluorescent excitation analysis) of the iodine content of tissue samples from dogs with 48 hour old myocardial infarctions. Tissue samples were obtained 10, 30, 60 and 180 minutes after the intraveneus administration of 2 ml/kg body weight of diatrizoate meglumine and sodium (Renografin-76). At all time intervals, the iodine concentration of infarcted tissue was at least threefold greater than that of normal myocardium. At 180 minutes the ratio between iodine concentration in infarcted myocardium and that in normal myocardium was 8.5 and between that in infarcted myocardium and that in blood was 2.6. The iodine concentration in the liver was similar to or greater than that in the infarcted area at time intervals after 10 minutes. These results suggest that the intraveneus administration of contrast material may facilitate the identification of acutely infarcted myocardium with computerized X-ray transmission tomography.
Energy and the structure of social institutions

The energy crisis is an aspect of the larger approaching crisis of expanding industrial society in a world in which certain critical parameters are finite. This megacrisis involves the role of growth in population, production, consumption, and waste. The insitutions of modern industrial society have been better adapted to promote this growth than to control or direct it. Even in societies where mechanisms of state planning should, in theory, enable government to deal rationally with the growth problem, ideological commitments to general growth have, in effect, prevented the problem from being addressed. In the United States, the pervasive commitment to growth has been built into institutional arrangements to a degree that handicaps efforts to consider the energy problem in its full context. Energy policy therefore tends to be reactive to events rather than the result of a comprehensive long-range assessment of needs and priorities.
A Comparative Study of the Stiller-Smith and Slider-Crank Mechanisms for Eight-Cylinder Internal Combustion Engine Use

This paper reports that the possible alternatives to the slider-crank for internal combustion engine use, the Scotch yoke in its various forms and inversions has received considerable attention. Among these, the Stiller-Smith mechanism has shown promise as being a viable option. Kinetostatic models were formulated to determine loading within similar eight-cylinder, four-stroke, compression-ignition engines with emphasis placed on comparing the number and similarity of mechanism components, implications of component and linkage motions, the loading experienced by similar bearing surfaces, and the friction losses of specific components.
The Influence of Ethnic Identity on Self-Authorship: A Longitudinal Study of Latino/a College Students.

This longitudinal study of Latino/a college students considers the influence of Latino/a college student experiences and ethnic identity on holistic development. Findings indicate that although similar characteristics are seen among Latino/a students, the role of recognizing and making meaning of racism is a significant developmental task. This is consistent with other ethnic and racial identity theories, yet this model considers all three dimensions of holistic development: cognitive, identity (intrapersonal), and interpersonal.
Preparation of Alkanethiol Monolayers on Mild Steel Surfaces Studied with Sum Frequency Generation and Electrochemistry

An n-alkanethiol, octadecanethiol (ODT), monolayer was successfully prepared onto an oxide-free mild steel (MS) surface under cathodic polarization in a 0.1 M LiCl/CH(3)OH solution containing 1 mM ODT. Cyclic voltammetry (CV) and electrochemical impedance (EIS) and sum frequency generation (SFG) spectroscopy were applied to study and characterize the adsorption of ODT at a MS surface. In 0.1 M LiCl/CH(3)OH solution containing 1 mM ODT, CV of the MS electrode shows a dramatic decrease in charging current and a positive shift in oxidation potential when compared to a solution without ODT. The interfacial capacitance was obtained as 2.52 microF/cm(2) from the impedance data. An average chain tilt angle of 48 degrees for the ODT molecules was deduced from the comparison of the interfacial capacitances of the ODT/MS and ODT/Au monolayers. X-ray photoelectron spectroscopy confirmed the formation of the ODT monolayer on mild steel. The ppp SFG spectrum of the ODT-modified MS features three strong methyl vibrational modes at 2877, 2943, and 2967 cm(-1), indicating the formation of the oriented and densely packed ODT monolayer. However, the appearance of the two weak CH(2) groups' vibrational modes at 2850 and 2914 cm(-1) implies the presence of defects in the ODT monolayer. ODT/Au films were prepared to compare with the ODT/MS films. Orientation analysis of the air/solid interface suggests that the methyl group of ODT/Au films has a tilt angle of 30 degrees , while the methyl group of ODT/MS films has a tilt angle of 23 degrees . Water was found to have an impact on the shape of the SFG spectra of ODT/MS. This suggests that the solution penetrated through the defects to reach the MS surface.
The genomic sequence of a virulent bovine viral diarrhea virus (BVDV) from the type 2 genotype: detection of a large genomic insertion in a noncytopathic BVDV.

Abstract A second genotype of bovine viral diarrhea virus, BVDV genotype 2 or BVDV 2, has been identified based on phylogenic analysis of sequences from the 5′ untranslated region of the viral RNA. In this study, we derived the complete nucleic acid sequence of a virulent BVDV 2 virus, BVDV2-890, isolated from an animal that died of an acute uncomplicated BVDV infection. BVDV2-890 is noncytopathic in cell culture and does not produce a p80 viral polypeptide. The ORF of BVDV2-890 is 11,922 nucleotide bases long and codes for 3973 amino acids. In comparison, the ORFs of other noncytopathic pestiviruses are shorter by about 250 nucleotides. The sequence identity at the amino acid level, between BVDV2-890 and published sequences for other pestiviruses, is 74% or less. The most conserved nucleotide and amino acid sequences between BVDV2-890 and other pestiviruses are located in the region coding for the nonstructural protein p80. The least conserved are in the regions coding for the structural polypeptide gp53 and nonstructural polypeptides p54 and p58. The larger size of the BVDV2-890 ORF is due to a 228-nucleotide insertion in the portion of the genome coding for the viral polypeptide p54. The location of this insertion was upstream from those reported in cytopathic pestiviruses. This insertion was not characteristic of all of the BVDV 2 viruses or all of the virulent BVDV 2 viruses.
Theory of transient energy transfer in gallium arsenide

Numerical calculations are given for optical two-beam coupling in undoped, semi-insulating GaAs using picosecond pulses. Absorption at the intrinsic defect EL2, two-photon absorption, free-carrier absorption, photorefractive gratings, free-carrier gratings, and absorption gratings are included. Results for normalized probe transmission as a function of pump fluence and as a function of pump-probe delay show that the major effects are energy transfer from pump to probe or from probe to pump (depending on crystal orientation) due to the photorefractive effect, two-photon absorption, and free-carrier transient energy transfer from the pump to the probe. >
Relaxing Passivity for Human-Robot Interaction

Robots for high-force interaction with humans face particular challenges to achieve performance and coupled stability. Because available actuators are unable to provide sufficiently high force density and low impedance, controllers for such machines often attempt to mask the robots' physical dynamics, though this threatens stability. Controlling for passivity, the state-of-the-art means of ensuring coupled stability, inherently limits performance to levels that are often unacceptable. A controller that imposes passivity is compared to a controller designed by a new method that uses limited knowledge of human dynamics to improve performance. Both controllers were implemented on a testbed, and coupled stability and performance were tested. Results show that the new controller can improve both stability and performance. The different structures of the controllers yield key differences in physical behavior, and guidelines are provided to assist in choosing the appropriate approach for specific applications.
Electronic and chemical behavior of oxygen in BaO films on Ir(100)

Abstract A new surface analysis technique involving low energy electron reflection (LEER) has been used to separate the electron affinity and position of the conduction band edge for BaO single crystal films epitaxially grown on Ir(100) substrates. AES and LEED were used in the study for characterizing chemical and structural effects. Active films have a work function of 1.3 eV with an electron affinity of 0.6 eV. Thermal activation was principally the result of the generation of O-vacancy donors by O diffusion into the substrate and not by evaporation of O from the coating. Donor generation could be retarded by the formation of an oxide diffusion barrier at the substrate interface or by pre-saturating the substrate surface region with oxygen. Electron bombardment desorption caused changes in surface stoichiometry which increased the worl function by increasing the electron affinity. Poisoning by oxygen took place by neutralization of O- vacancy donors until near intrinsic conditions occurred. Additional oxygen accumulates at the surface increasing the electron affinity. Since the Fermi level does not go below the mid-gap position, the formation of Ba-vacancies does not seem likely. Reactivation is possible but the initial donor density cannot be achieved due to O saturation of the substrate.
Entrainment response of bed sediment to time‐varying flows

Unsteady flows are ubiquitous in nature. In order to understand the behavior of sediment when subjected to unsteady flows, a set of experiments was performed in a rectangular duct with a mobile bed. A computer-operated valve governed the velocity of the water in the duct, and the flow velocity, wall shear stress, and vertical distribution of suspended sediment were simultaneously measured. Beds composed of 120 μm and 580 μm diameter sand were investigated. Both quasi-steady flows and pulse flows were simulated in the duct. For the pulse flows the water was accelerated at a constant rate to a peak velocity and then decelerated at a constant rate to zero velocity. Phase lags were observed between the bed shear stress and the upward flux (entrainment) of sand from the bed. The phase lags were larger for tests with fine sand than for tests with coarse sand. Differences were attributed to differences in bed roughness and flow Reynolds numbers. Relations based on flow acceleration and sediment size were developed for predicting the entrainment phase lag. Large phase lags can have a considerable impact on the amount of sediment transported by boat wakes, waves, and other unsteady flows.
The magnocellular and parvocellular paraventricular nucleus of rat: Intrinsic organization

The magnocellular and paravocellular regions of the rat hypothalamic paraventricular nucleus (PVN) were examined in several hundred brains. Converging qualitative and quantitative anatomical methods, including Golgi impregnations, Nissl stains, silver stains, and immunocytochemistry were used to study the intrinsic organization of the PVN with light, scanning, and transmission electron microscopy. A computer-assisted quantitative analysis of dendritic branching patterns was used to examine total dendritic length, center of mass, orientation of dendritic tree, and several other parameters of dendritic organization and revealed statistically significant differences between cells in the lateral and posterolateral magnocellular and medial parvocellular areas of PVN. Electron microscopy, Golgi impregnation, and neurophysin immunohistochemistry showed that dendrites of posterolateral cells were generally oriented perpendicular to the third ventricle; dendrites of cells in the lateral PVN usually projected medially from the perikaryon. Cells in the medial zone of PVN had dendritic trees which often paralleled the third ventricle. Large numbers of axons entered and left PVN ventrally near the midline and laterally in the area of the posterolateral PVN; axons generally were oriented parallel to the mean major axis of dendritic trees in these areas. Ultrastructural examination of serial thin sections showed a peculiar astroglia multiple lamellar isolation of axodendritic synaptic contacts. Intrinsic axons commonly arose from parvocellular but not from magnocellular neurons and contacted dendrites of both medial parvocellular and more lateral magnocellular neurons. Synapses were found on shafts and spines of dendrites, on perikarya and somatic appendages, and invaginated into the soma. Both dendrites axons with large neurosecretory vesicles and immunostained with neurophysin antiserum were found postsynaptic to other axons. Presynaptic neurosecretory axons were not found within the PVN. A semiquantitative analysis of catecholamine axons identified with the glyoxylic acid method and fibers immunoreactive with ACTH and Substance P antisera indicated that the parvocellular region of PVN received ggreater innervation than the lateral magnocellular area; similarly, a reater density of stained fibers was found in the medial parvocellular PVN region with Golgi impregnations and silver stains. With a stereological analysis of 1-micrometer plastic sections, the parvocellular area had a significantly greater neuropil to cell volume ration, with cells accounting for 48 +/- 9% in the lateral magnocellular zone, but only for 26 +/- 7% in the parvocellular area. A quantitative analysis of vasculature from thin sections showed that the PVN had 3.3 times more blood vessels, and 3.6 times more lumen perimeter than a control area ventrolateral to PVN; an interesting finding here was that the medial parvocellular PVN had a high degree of vascularity, not significantly different from the lateral magnocellular zone...
Expression of a unique plastid-localized heat-shock protein is genetically linked to acquired thermotolerance in wheat

We have used a combination of molecular and classical genetic approaches to delineate the relationship between a specific HSP member and cell viability under heat stress. Using recombinant inbred lines (RILs) of wheat, derived from a cross of the thermotolerant cultivar ‘Mustang’ and the thermosusceptible cultivar ‘Sturdy,’ we have identified a unique HSP and a differentially expressed cDNA sequence, both related to the plastid-localized HSP26 gene family, that are closely associated with acquired thermotolerance in wheat. An isoform of HSP26 was synthesized under heat stress in all examined thermotolerant RILs and ‘Mustang’, and was absent in all examined thermosusceptible RILs and ‘Sturdy.’ Using a modified differential-display method, we have also identified a gene-specific cDNA sequence that is similar to other known members of the wheat HSP26 gene family and is selectively expressed in ‘Mustang’ and most of the examined thermotolerant RILs, but not expressed in ‘Sturdy’ and all the thermosusceptible RILs. These results suggest a genetic linkage between the acquired thermotolerance trait and the differential expression of a unique member of the HSP26 gene family.
Centering Social Justice in the Study of Higher Education: The Challenges and Possibilities for Institutional Change.

In this article, we illustrate and grapple with the challenges of doing social justice work in a neoliberal academic environment. Specifically, we consider our experiences of creating a social justice concentration in a graduate program where higher education serves as the focus of study. In so doing, we draw on information from a number of sources to explore three key considerations: (1) the institutional context within which we developed the social justice concentration, (2) the forms of mobilization we engaged in leading to implementation, and (3) the challenges and opportunities we faced during this process. Although we suggest that the challenges match and in some cases far outweigh the opportunities, we argue that there is no acceptable alternative to not doing this work. We believe we must continue to strive to center subjugated knowledges in the academy, to honor different ways of knowing, and to work for progressive social change by engaging in projects that create an academy that is truly inclusive.