cssi/SciSciGPT-SciSciNet huggingface dataset:
Food safety regulation: is the Delaney clause the problem or symptom?

The Delaney ‘anticancer’ amendment to the Food, Drug, and Cosmetic Act of 1938 is a prominent example of ‘zero risk’ legislation. The relevant clauses prohibit a finding of safety for any relevant substance found to induce cancer in humans or animals. It is argued that the Delaney approach to safety regulation is not only misguided, but that relaxation of the law - for example, to permit substances that pose ‘insignificant’ cancer risks - would produce only marginal improvement in regulation. A major shift in regulation that permits some form of cost-benefit analysis is the only way to move toward rational policy choices.
Iliac to Popliteal Artery Bypass through the Iliac Wing: An Alternative Extracavitary Route for Management of Complex Groin Injuries

Extracavitary bypass through the iliac wing allows placement of the grafts into the posterior thigh and is another alternative route when an obturator bypass is not possible, or an axillary-popliteal bypass is to be avoided. The transiliac wing bypass is relatively simple and easy to perform. The bypass route is short and direct, has excellent inflow, and is accompanied by minimal neurological or bleeding risks. An illustrative case is presented with a complete description of the operative technique. Review of the literature is also included.
The Health Innovations Scholars Program: A Model for Accelerating Preclinical Medical Students’ Mastery of Skills for Leading Improvement of Clinical Systems

Dramatic changes in health care require physician leadership. Efforts to instill necessary skills often occur late in training. The Heath Innovations Scholars Program (HISP) provided preclinical medical students with experiential learning focused on process improvement. Students led initiatives to improve the discharge process for stroke patients. All students completed an aptitude survey and Quality Improvement Knowledge Assessment Test (QIKAT) before and after the program. Significant improvements occurred across subject areas of leadership (18.4%, P < .001), quality and safety (14.7%, P < .001), and health care systems operations (21.2%, P < .008), and in the domains of knowledge (25.9%, P < .001) and skills (25.2%, P < .001). Average cumulative QIKAT results improved significantly (8.33 to 9.83, P = .04). Three of 4 recommended interventions were implemented. Furthermore, students engaged in other process improvement work on return to their home institutions. The HISP successfully advanced preclinical medical students' ability to lead clinical systems improvement.
A rule-based interpretation system for segmentation of seismic images

Abstract A rule-based interpretation system for segmenting seismic images based on signal character is presented in this paper. The system consists of two substructures: a texture analyzer and an intelligent interpreter. The texture analyzer adapts the “texture energy measurement” method developed by Laws to extract discriminant features from the texture-like signal image. The major function of the analyzer is to assign a vector of initial certainty factors (CFs) to each texel in the image based on the extracted feature measures. The elements of the CF vector essentially correspond to the degree of membership of the texel to each of the texture regions in the image. The intelligent interpreter, which is the rule-based system, is made up of a knowledge database, a reasoning engine and a parallel region growing controller. Whenever a growing region requests to classify one of its boundary texels, a fact list is formed carrying information about the texel and its neighborhood. The interpreter takes the fact list and searches in the knowledge database to determine if any rules can be exercised. After a sequence of executions of rules and manipulations of CF numbers, a final CF vector emerges. If this vector favors the requesting region by having its corresponding component element exceed a preset threshold, the texel is classified to this texture class and merged into the requesting region. A test run of the system on a piece of a seismic section shows that it can very successfully segment it into regions of common signal character. A noticeable advantage of the intelligent interpreter over other conventional classification techniques is its capability of patching small areas in the image for which the original data apparently do not provide enough discriminant information. An example illustrating these results on real seismic data from the Gulf of Mexico is presented.
Inhibition of Seed Germination by Salt and its Subsequent Effect on Embryonic Protein Synthesis in Barley

Summary Two cultivars of barley, Prato and California Mariout 72 (CM 72), show significant differences in response to salt stress during seed germination (Ramagopal, 1988). Seeds of these cultivars were imbibed in germination-inhibitory concentrations of salt, 0.34M NaCI (Prato) and 0.51M NaCI (Prato and CM 72), for 3 days; the ungerminated seeds were selected and further incubated for 24 h in a nonsaline medium, at which time the seeds were on the verge of germination. The embryos were labeled in vivo with 35S-methionine and protein synthesis was assayed during salt stress and recovery. The embryos of both cultivars retained their ability to incorporate 35S-methionine into protein under prolonged stress. The salttolerant cultivar (CM 72) showed a higher capacity to resume protein synthesis than the salt-sensitive cultivar (Prato) upon removal of salt. Newly synthesized proteins were analyzed by sodium dodecylsulfate- polyacrylamide gel electrophoresis, fluorography, and densitometry. Although some of the proteins made during salt stress and recovery were common, distinct differences were also observed. Eight new proteins were made exclusively during salt stress and seven during recovery. All of the newly induced proteins in CM 72 and Prato were qualitatively identical, but the expression of some of them indicated that quantitative differences existed between the two cultivars. Further, the protein profiles of recovering seed embryos were distinctly different from those of germinating embryos not previously exposed to salt. The findings suggest that prior salt stress alters the pattern of proteins normally associated with the germinating embryos.
European Journal of Public Health—Comments on Ken Judge's article

Professor Ken Judge underlines the importance of undertaking research on the politics of health policy. We agree on that. But I do not share his skepticism about the possibility of studying ‘values’ (I assume that he means political values). Political Sciences study not only values but, most importantly, power (class, gender, race, national and other types of power relations) and its expression through political representative …
Igneous dikes on Mars revealed by Mars Orbiter Laser Altimeter topography

The origin of Martian grabens has remained controversial for decades, given the nonuniqueness of graben morphology and conflicting interpretations of dike-induced or faultingbased formation processes. We use measurements from the Mars Orbiter Laser Altimeter to identify the characteristic topographic signature at the surface of an igneous dike beneath a Martian graben. Our results suggest that this subtle but diagnostic signature can be used to test competing interpretations of the formation of grabens and associated fissures and collapse depressions.
Development and application of desirable ecological models

Abstract The concepts of model validation and model realism are reconsidered in terms of the domain of applicability of a model. Ambiguity in both the application and the conceptualization of model validation is a problem for clearly assessing the usefulness of models. Model desirability (as well as the concepts of model adequacy and model reliability) is developed in a set theoretic context which is intended to reduce the ambiguity that often obstructs clear discussions of model validation. A set of criteria for defining desirable models is outlined and a list of principles for increasing model desirability is provided. It is shown that models of known adequacy can be used to reduce sample size in traditional statistical sampling procedures. A derivation using models and Bayes' theorem is provided as an example of such an application.
Depression of spontaneous and lonophore-induced transmitter release by ruthenium red at the neuromuscular junction☆

The effects on spontaneous and ionophore-induced transmitter release of the inorganic dye, ruthenium red (RuR), a known inhibitor of calcium binding sites, were observed at the frog sartorius neuromuscular junction using intracellular recording techniques. Both crude and purified RuR, at concentrations of 1 and 5 micron depressed or blocked spontaneous release of acetylcholine (ACh) and reduced postsynaptic sensitivity to ACh, the crude dye being more potent than the pure. Pretreatment of muscles with RuR prevented the catastrophic reaction of junctions to 100 micron X537A ionophore. Increased levels of Ca2+ restored spontaneous transmitter release to control levels after depression or blockade by RuR. It was concluded that RuR blocks a critical membrane-bound binding site for calcium which is necessary for quantal release of transmitter.
Isolated palmar displaced fracture of the base of the index metacarpal: a case report.

The current literature contains an abundance of references citing fracture dislocations of the thumb, ring, and small finger carpometacarpal joints, but there are few reports of index and long finger carpometacarpal fractures or fracture dislocations. Isolated injuries of these joints are decidedly rare, and in those instances where fracture dislocations are reported, they are essentially all dorsally directed and usually involve multiple joints. Only four cases of isolated palmar dislocation of the index and long finger carpometacarpal joints have been reported. These reported cases have not documented associated bony fractures, and none involved only the index metacarpal. We present a case of an isolated fracture dislocation of the base of the index metacarpal with displacement of the base fragment into the palm. examination was remarkable for diffuse hand swelling, and a dorsal bony defect was found despite the marked swelling. Additionally, there was an area of tenderness ulnar to the thenar emminence. and attempted flexion of the fingers elicited palmar pain. Anteroposterior and oblique x-ray films showed irregularity of the base of the index metacarpal and a
The Analysis of Social Interaction Data: A Nonparametric Technique

A nonparametric technique is presented that is appropriate for comparing two social interaction matrices, either when both are obtained empirically, or when one is generated from some given theoret...
This Changes Everything: Transforming the Academic Library

ABSTRACT Library users and their expectations for services and collections have changed. Among the factors driving change are: networked technologies, powerful search engines available to all, social technologies and the digitization of everything, to name a few. A research university library staff reorganized to meet changed expectations and succeeded in transforming the organization and its culture. This article describes alterations in the library's key functions that produced a new level of readiness to serve the university's students and faculty into the future. The transformed library is outward facing, de-siloed, technology diffused, collaborative, and operated by an engaged staff who demonstrate leadership in small and large ways in all sections of the organization.
Structure and viscosity of rhyolitic composition melts

Abstract The average local structure of a rhyolitic composition glass has been determined at 25°C using X-ray radial distribution analysis (RDA) and quasi-crystalline modelling and is best described as similar to that in a stuffed framework composed principally of six-membered rings of Si and Al tetrahedra (basically a stuffed tridymite-like model). Using this model it is possible to calculate a density (2.41 g/cm 3 ) which compares well with the measured density (2.40 g/cm 3 ); a structural model based on four-membered rings (an albite-like model) results in a substantially higher calculated density (2.60 g/cm 3 ). We suggest that the rhyolite glass structural model is appropriate for rhyolitic melts, based on evidence from the recent literature. New viscosity data for an anhydrous rhyolite composition measured between 1200°C and 1500°C are presented and interpreted in terms of our proposed structural model and previous melt structure models for the major normative components of rhyolite. A mechanism for diffusion and viscous flow in framework silicate melts (including rhyolite composition) is proposed on the basis of recent molecular orbital calculations and molecular dynamics simulations of silicate and fluoride melts.
A convenient purification of porcine pancreatic lipase free of proteolytic activity.

Abstract A rapid, improved procedure for the purification of porcine pancreatic lipase (EC 3.1.1.3) essentially free of proteolytic activity has been developed. Commercially available pancreatin was extracted with anhydrous organic solvents to remove lipids. Solubilization in the presence of phenylmethylsulfonylfluoride inactivated chymotrypsin, while treatment with 0.2 m 2-mercaptoethanol and 2 m urea inactivated trypsin. Gel filtration through Sephadex G-100 provided lipase that was 45–60% pure in 70–90% overall yield. The effects of lipolysis on membrane-bound protein in the absence of significant proteolysis can be studied unambiguously.
Deviations from Ultrametricity in Phage Protein Distances

Distances in biological databases are known not to be ultrametric. Deviations from ultrametricity can however reveal useful features of biodata. In the present study we examine deviations from ultrametricity of the distances between known phage proteins quantified in two senses: (1) the failure of triangles to be isosceles and (2) failure of every point to be the center of any sphere in which it resides. The deviations from these two ultrametric properties undergo qualitative changes as a function of the distance. Below we describe these changes and how they can be observed. We further argue that the distances at which the qualitative changes take place reveal intrinsic scales in the dataset. Such scales are important for choosing threshold values of the distance in various algorithms and reveal natural chunking of the data that can be used to decide clade levels in phage phylogeny.
SME filter approach to multiple target tracking with false and missing measurements

The symmetric measurement equation (SME) filter for track maintenance in multiple target tracking is extended to the general case when there are an arbitrary unknown number of false and missing position measurements in the measurement set at any time point. It is assumed that the number N of targets is known a priori and that the target motions consist of random perturbations of constant-velocity trajectories. The key idea in the paper is to generate a new measurement vector from sums-of-products of the elements of 'feasible' N-element data vectors that pass a thresholding operation in the sums-of-products framework. Via this construction, the data association problem is completely avoided, and in addition, there is no need to identify which target measurements may correspond to false returns or which target measurements may be missing. A computer simulation of SME filter performance is given, including a comparison with the associated filter (a benchmark) and the joint probabilistic data association (JPDA) filter.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Influence of room temperature on the growth of house mice.

Inbred C57BL/6 house mice, Mus musculus , were born and reared until weaning under standard conditions of food supply, housing, illumination and litter size. Throughout a 12-month period, the mice were weaned and weighed at exactly 21 days of age. The temperature of the room in which they were housed was recorded daily. Mice born during the warmer indoor months weighed significantly more at weaning than those born during the cooler months. The influence of environmental temperature on the preweaning growth of these mice, however, appeared to be limited to their third week of life.
Religious Involvement and Perceived Social Support: Interactive Effects on Cardiovascular Reactivity to Laboratory Stressors

Religious involvement has been linked to reduced risk of cardiovascular morbidity and mortality. This may reflect lower cardiovascular reactivity (CVR) among individuals high in religious involvement. The relationship between religious involvement and reactivity may overlap with the effects of other psychosocial factors. This study examined religious involvement, social support, and hostility in relation to CVR in the laboratory. Results showed an interactive effect of perceived social support and religious involvement on systolic blood pressure (SBP) reactivity. Participants reporting a high level of religious involvement showed lower SBP reactivity only when they also reported high levels of social support. These findings encourage further research on the unique and conjoint effects of religiousness and other psychosocial variables on CVR.
Estimating body size of fossil sirenians

Estimates of fossil sirenian body size are important for understanding niche partitioning among possibly sympatric species. Because of the paucity of complete fossil skeletons, we explored the utility of three morphometric predictors of body size: (condylobasal skull length [BSL]; occipital condyle width [OCW]; and foramen magnum width [FMW]) in extant sirenians—Florida manatees (Trichechus manatus latirostris) and dugongs (Dugong dugon)—and then applied these to obtain estimates of body size in extinct sirenian taxa. Condylobasal length of the skull is a more accurate predictor of body size in extant Florida manatees and dugongs than are width of the occipital condyles or width of the foramen magnum. Body length (BL) is predicted more accurately than is body weight (BW) for all three morphometric predictors. For our sample of fossil sirenians, BSL, OCW, and FMW were used to generate predicted BLs and BWs. Preliminary assessments of fossil sirenian faunas from Florida and India suggest that body mass could have been one of several possible important morphological parameters accounting for feeding niche separation.
Subdividing the Age Group of 85 Years and Older to Improve US Disease Reporting

The standard terminal age category in disease reporting in the United States has been 85 years and older since the 1940s, but the dramatically increasing share of the US population reaching this age has rendered the single category inadequate for surveillance, research, and analysis. Important age-specific variations in mortality among the oldest old are masked by the continued use of this category. Greater specificity in age-specific data for the oldest old would aid in disease surveillance and etiologic research and broaden awareness and understanding of human longevity.
Transmembrane signalling by interferon-α

Human leukocyte interferon (IFN-alpha) binds to discrete cell surface receptors on target cells, and thereby alters gene expression. Transmembrane signaling by IFN-alpha involves the production of DAG without an increased intracellular free calcium concentration, and the subsequent activation of calcium-independent isoforms of PKC (beta and epsilon). Selective PKC inhibitors (H-7 and staurosporine) can block the ability of IFN-alpha to activate the transcription of a distinct set of genes, called the IFN-stimulated genes (ISG), and to protect cells against viral infection. IFN-alpha also induces the rapid changes in protein phosphorylation, which may include latent transcription factors for ISGs.
Integrated structural analysis and design using three-dimensional finite elements

A design approach that combines iterative structural analysis with a traditional iterative optimization algorithm is applied to the optimum design of the shape of a hole in a plate in tension. The plate is modeled by threedimensional finite elements, and an element-by-el ement preconditioned conjugate gradient iterative algorithm is used for solving the equations of equilibrium. Several parameterizations of the optimum shape are considered, and it is shown that a sine series can describe the optimum shape with only three design variables, whereas other series require seven variables for similar results. The optimum shape compares well with an experimental optimum obtained by A. J. Durelli. An investigation is performed to determine the best way of obtaining finite-difference derivatives of the stresses with respect to design variables. It is shown that a method based on modifying the equations of equilibrium for the perturbed problem performs best. The benefit of the integrated approach is determined by comparing convergence with different initial iterates for the displacement field. It is shown that using the final iterate of the previous solution can reduce the number of analysis iterations by about 40% compared to starting with a zero initial iterate.
‘Indirect rule’ and the rule of law in Samoa

Abstract The politics of land in the Pacific are entwined with the politics of custom, and both are entwined with the politics of island governance. The arrival of Europeans heightened these politics, and the application of European conceptions of the sovereign state modified them in ways that changed the expression of social relations on the land. This aspect of human territoriality—the control over natural resource access and use—is commonly overlooked in analyses of state formation. Yet it is essential in understanding the efficacy of state power, especially in the Pacific. Pacific island states were generally created under colonial rule and through colonial applications of indirect rule. But indirect rule also created the state's dependence on the character of custom and, thereby, reinforced a basic tension undermining state authority: by protecting the local control of land, it limited state capacities to articulate and enforce the rule(s) of law. This article examines the way this tension was mediated in Samoa, east and west of a line of partition. It is concerned principally with tracing the evolution of formal political relations, institutions, and processes effecting patterns of territorial control, and with understanding relationships between territorial control, political autonomy, and the capacity to regulate local environmental practices.
Models for uleine-alkaloid biogenesis

Abstract Possible mechanisms by which the C2-unit of the tryptamine bridge of condylocarpine-type alkaloids can be lost to give the uleine skeleton are considered. A terminally-oxidized β-C2 substituent on an α-methyleneindoline system could not be cleaved, but a β-C3 acid unit fragmented readily.
Can patients with type 2 diabetes be treated with 5'-AMP-activated protein kinase activators?

AMP-activated protein kinase (AMPK) has been identified as a target for development of pharmaceuticals for prevention and treatment of type 2 diabetes. Chemical activation of AMPK in experimental animals using 5-aminoimidazole-4-carboxamide (AICAR) has previously been reported to activate AMPK, stimulate fat oxidation, stimulate glucose uptake into muscle, inhibit lipogenesis and cholesterogenesis, increase hexokinase and GLUT-4 in muscle, and increase insulin sensitivity. Animals with metabolic conditions similar to type 2 diabetes show improvement in glucoregulation with chronic AICAR injections. A more recent study of normal human subjects demonstrated increased uptake of a glucose analogue into skeletal muscle in response to AICAR infusion. The current study by Boon, et al in this issue of Diabetologia demonstrates reduction of glucose production and improvement in glucoregulation in patients with type 2 diabetes infused with AICAR at much lower doses than were previously used in rats and mice. This study provides additional evidence that AMPK-activating pharmaceuticals may be useful in prevention and treatment of type 2 diabetes.
Prenatal Diagnosis of the Organic Acidurias

Prenatal diagnosis for the genetic counselling of families at risk for having children with the life-threatening organic acidurias is advancing rapidly. The two major approaches to prenatal diagnosis are the assay for deficient activity of the enzymes in cultured amniocytes and the measurement of increased concentrations of the organic acids in the amniotic fluid. The latter, when done by stable isotope dilution analysis, is rapid, relatively inexpensive and very reliable.
Covers, matching and odd cycles of a graph

We link some well-known theorems and prove some new ones, each on one or more of the items of the title, and together illustrating their close relationship. The main tools are well-known similar conditions on maximum stable sets and maximum matchings, by which we prove theorems on the existence of odd cycles, including a generalization of Konig's equality between the matching and covering numbers of a bipartite graph. We deal with the question ''How nearly bipartite is a graph?'' and conjecture an inequality involving the matching and covering numbers and the number of disjoint odd cycles.
The effects of a single memantine treatment on behavioral alterations associated with binge alcohol exposure in neonatal rats

Abstract Background The third trimester in human fetal development represents a critical time of brain maturation referred to as the “brain growth spurt”. This period occurs in rats postnatally, and exposure to ethanol during this time can increase the risk of impairments on a variety of cognitive and motor tasks. It has been proposed that one potential mechanism for the teratogenic effects of ethanol is NMDA receptor-mediated excitotoxicity during periods of ethanol withdrawal. In neonatal rats, antagonism of NMDA receptors during ethanol withdrawal, with drugs such as MK-801 and eliprodil, has been shown to mitigate some of the behavioral deficits induced by developmental ethanol exposure. The current study examined whether memantine, an NMDA receptor antagonist and a drug used clinically in Alzheimer's patients, would attenuate impairments associated with binge ethanol exposure in neonatal rats. Methods On postnatal day 6, rats were exposed to 6 g/kg ethanol via intubation with controls receiving an isocaloric maltose dextrin solution. Twenty-one hours following the ethanol binge, rats received intraperitoneal injections of memantine at 0, 10, 15, or 20 mg/kg. Ethanol's teratogenic effects were assessed using multiple behavioral tasks: open field activity, parallel bars and spatial discrimination reversal learning. Results Ethanol-treated rats were overactive in the open field and were impaired on both reversal learning and motor performance. Administration of 15 or 20 mg/kg memantine during withdrawal significantly attenuated ethanol's adverse effects on motor coordination, but did not significantly alter activity levels or improve the spatial learning deficits associated with neonatal alcohol exposure. Conclusion These results indicate that a single memantine administration during ethanol withdrawal can mitigate motor impairments but not spatial learning impairments or overactivity observed following a binge ethanol exposure during development in the rat.
Short-term population dynamics of Tisbe cucumariae (Copepoda: Harpacticoida)

Population dynamics of a benthic harpacticoid copepod (Tisbe cucumariae) were studied in a seawater-system holding tank during fall-spring, 1979/1980, and January, 1981. These populations were opoortunistic scavengers, especially on the dead bodies of Ciona intestinalis, a solitary tunicate. Copepod population densities, life-history stage structures, sex ratio and percentages of females with egg sacs were determined in the absence or in the presence of dead tunicates (from death through dissolution to final disappearance). Taken together, all the data are consistent with a hypothesis for food-dependent cycling of populations of T. cucumariae through the following 4 density states: (1) a maintenance state of low density, which is the usual condition during the absence of a concentrated food source; (2) a colonization state of moderate density, which results from attraction and immigration to a new food source; (3) a bloom state at the food source, where a high density results from intensive reproduction combined with a tendency of all life stages to remain at the site; (4) a dispersal state of moderate density as the copepods emigrate from the site of the consumed food. Evidence is also presented for a facultative slowing of naupliar development in T. cucumariae in the absence of a concentrated food source such as a dead tunicate. Possible advantages afforded by delayed development are discussed in terms of risk-spreading in a stochastically hostile environment.
A RIGOROUS TEST FOR SPARC'S CHEMICAL REACTIVITY MODELS : ESTIMATION OF MORE THAN 4300 IONIZATION PKAS

Ionization pKas for a large set of molecules were calculated using reactivity models developed in the computer program SPARC. SPARC uses relatively simple computational algorithms based on fundamental chemical structure theory to estimate ionization pKas of organic molecules strictly from molecular structure. Molecular structures are broken at each essential single bond into functional units with intrinsic properties. Reaction centers (acid or base) are identified and the impact of appended molecular structure on ionization pKa is quantified by perturbation theory. Resonance, electrostatic, solvation and H-bonding models have been developed and tested on 4338 pKas for 3685 compounds. The RMS deviation for the acids and the amino reaction center was 0.36 pKa units whereas that for the in-ring N and = N reaction centers was 0.41. Microscopic ionization constants, zwitterionic constants, isoelectric points, and molecular speciation as a function of pH can be calculated using the SPARC models.
A real time, hierarchical multimicroprocessor image reduction system

Abstract This paper presents a hierarchical multi-microprocessor system in three different types. These system-types are: (i) the Complete Quad-tree of Microprocessors, (ii) the Pseudo Ternary-tree of Microprocessors and (iii) the Parallel Array of Microprocessors. The proposed system-types realize the reduction of the image information, in real-time, by using the regular decomposition methodology. A significant application of the discussed system is that it could be used as a preprocessing part of the real-time WHT systems, for the fast parallel/pipeline image coding and transmission.
Transition Services—Systems Change for Youth with Disabilities? A Review of State Practices

Respondents from 49 state education agencies completed a survey describing state-level implementation of transition services for youth with disabilities. All states used technical assistance and cross-disciplinary training as their primary systems change strategies, and the majority of these states viewed these strategies as effective. Relatively few states used additional state legislative mandates to promote transition services. This article discusses the role of the state education agency in implementing systems change in special education transition services.
Spectroscopic and microscopic investigation of the corrosion of D-9 stainless steel by lead-bismuth eutectic (LBE) at elevated temperatures. Initiation of thick oxide formation

Abstract Corrosion of 316/316L stainless steel by lead–bismuth eutectic (LBE) at elevated temperature was investigated by examination of samples after 1000, 2000, and 3000 h of exposure at 550 °C, using SEM, XPS with sputter depth profiling, and TEM. The process by which localized oxide failure becomes extensive thick oxide formation was investigated. Under our experimental conditions, iron was observed to migrate outward while chromium did not migrate above the original metal surface. The thin oxide layer on the D-9 sample resembled 316L cold-rolled samples, while the thick oxide on D-9 resembled annealed 316L oxide. With continued exposure, thick oxide grew to cover the entire surface.
Relaxation effects in a simple Mössbauer model

Abstract Spurious effects can arise from the neglect of relaxation in simplified calculations of the Mossbauer effect from an impurity source. This is illustrated by calculations of the Mossbauer effect from an atom bound in an external barmonic potential which is also coupled with a finite relaxation time to a large system in thermal equilibrium. The following modificatin of conventional calculations of the f-factor is proposed to include relaxation effects: to take the thermal average of the transition matrix element before squaring it rather than after.
Regulation of α1(I) Collagen Messenger RNA Decay by Interactions with αCP at the 3′-Untranslated Region

Liver fibrosis is characterized by an increased deposition of extracellular matrix proteins, including collagen type I, by activated hepatic stellate cells (HSCs). Previous studies have shown that this increase is mediated primarily by a post-transcriptional mechanism. In particular, the RNA-binding protein alphaCP binds to the alpha1(I) collagen 3'-untranslated region (UTR) and stabilizes this RNA in activated, but not quiescent, HSCs. This study examines the role of alphaCP in the decay of transcripts containing the collagen 3'-UTR in extracts obtained from NIH fibroblasts and quiescent and activated HSCs. Using an in vitro decay system, alphaCP binding activity was competed out with the addition of wild type oligonucleotides, but not with mutant oligonucleotides. Competition of alphaCP binding activity increased the rate of decay of wild type transcripts containing the alphaCP 3'-UTR binding site, but not of transcripts containing a mutated binding site. Quiescent HSC extracts contain no alphaCP binding activity and have no difference in the rate of decay of transcripts with wild type and mutant binding sites for alphaCP. The addition of recombinant alphaCP was sufficient to increase the half-life of the wild type transcript, whereas that of the mutant transcript was minimally changed. In vitro decay assays performed with activated HSC extracts that contain alphaCP binding activity demonstrate a markedly reduced decay rate of wild type compared with mutant transcripts. In vivo small interfering RNA experiments targeting alphaCP showed a reduction of the binding activity of alphaCP and a concomitant reduction in intracellular levels of alpha1(I) collagen messenger RNA. In conclusion, this study demonstrates the direct role of alphaCP in the stabilization of alpha1(I) collagen messenger RNA by blocking RNA degradation in activated HSCs.
Effects on recipients of exposure to allogeneic donor leukocytes

Blood transfusion recipients are exposed to allogeneic donor leukocytes at the time of transfusion. Exposure to allogeneic donor leukocytes has been linked to a variety of complications of transfusion including primary HLA alloimmunization and platelet refractoriness, febrile nonhemolytic transfusion reactions, transmission of leukotropic viruses, transfusion-associated graft versus host disease, and transfusion-induced immune suppression. The development of high-performance leukodepletion blood filters and of low-leukocyte plateletapheresis machines has provided the technology to reduce recipient exposure to allogeneic donor leukocytes. This article provides a brief review of current information on the utility and shortcomings of these technologies for the prevention of leukocyte-mediated transfusion complications.
Synthesis of N,N-bis(trifluoromethyl)amino difluoromethylene trifluorovinyl ether

Abstract The first N-containing trifluorovinyl ether monomer (CF 3 ) 2 NCF 2 OCF CF 2 was synthesized. The starting perfluoroalkyl imine CF 3 –N CF 2 was converted to the perfluoroalkyl amine (CF 3 ) 2 NH by HF. The amine was converted into the carbamoyl fluoride (CF 3 ) 2 NC(O)F via reaction with carbonyl fluoride COF 2 in the presence of NaF. The carbamoyl fluoride was subjected to catalytic fluorination with molecular F 2 in the presence of CsF to afford the hypofluorite (CF 3 ) 2 NCF 2 (OF). The hypofluorite was added to CFCl CFCl to provide a saturated halocarbon ether. Dechlorination of the ether with zinc in DMSO resulted in the title monomer. The new vinyl ether monomer readily copolymerizes with TFE.
Nerve growth factor receptor expression in the young and adult rat olfactory system

Nerve growth factor (NGF) and its receptor (NGFR) are proteins that have a role in the normal development and survival of neurons in the peripheral and central nervous systems. During development, NGF is necessary for outgrowth of axons and establishment of synapses, and NGFR is the transmembrane protein that binds NGF and brings it into the cell. NGF and NGFR expression in the rat olfactory system have been studied previously, and age differences in NGFR are explored further in this study, using immunocytochemistry and immunoelectron microscopy to determine the changes in two different ages: postnatal day 5 and the adult. Dramatic differences were found in the distribution of NGFR immunoreactivity in the olfactory system of each of the two ages studied. Electron microscopy revealed that glial cells were responsible for this immunoreactivity.
Herpes simplex virus capsid assembly and DNA packaging: a present and future antiviral drug target

Herpes simplex virus (HSV) is an important pathogenic agent that causes recurrent oral and genital lesions, blindness and encephalitis. It is a member of the family Herpesviridae, which contains three subfamilies (alpha- beta- and gammaherpesvirinae) whose members infect humans to cause a variety of ailments, from benign rashes to nasopharyngeal carcinoma. Although this review focuses on HSV, the assembly steps that occur in the nucleus and the proteins involved are highly conserved among all family members, which suggests that antiviral agents that block these steps might be effective against many different herpesviruses and their associated diseases. Despite this potential, a broadly effective compound has yet to be realized, in part because many of the processes are only poorly understood in sufficient molecular detail. The goal of this review is to outline these intranuclear assembly steps and illustrate potential and existing antiviral strategies that exploit them.
Simulation of phase boundaries using constrained cell models

Despite impressive advances, precise simulation of fluid?fluid and fluid?solid phase transitions still remains a challenging task. The present work focuses on the determination of the phase diagram of a system of particles that interact through a pair potential, ?(r), which is of the form ?(r)?=?4?[(?/r)2n???(?/r)n] with n?=?12. The vapor?liquid phase diagram of this model is established from constant-pressure simulations and flat-histogram techniques. The properties of the solid phase are obtained from constant-pressure simulations using constrained cell models. In the constrained cell model, the simulation volume is divided into Wigner?Seitz cells and each particle is confined to moving in a single cell. The constrained cell model is a limiting case of a more general cell model which is constructed by adding a homogeneous external field that controls the relative stability of the fluid and the solid phase. Fluid?solid coexistence at a reduced temperature of 2 is established from constant-pressure simulations of the generalized cell model. The previous fluid?solid coexistence point is used as a reference point in the determination of the fluid?solid phase boundary through a thermodynamic integration type of technique based on histogram reweighting. Since the attractive interaction is of short range, the vapor?liquid transition is metastable against crystallization. In the present work, the phase diagram of the corresponding constrained cell model is also determined. The latter is found to contain a stable vapor?liquid critical point and a triple point.
Effect of surface tension gradient driven convection in a laser melt pool: Three‐dimensional perturbation model

A three‐dimensional model of the thermocapillary flow within the molten region during laser surface heating is developed. This physically corresponds to the process of a stationary laser beam irradiating on the surface of a moving workpiece. The recirculating flow due to the surface tension gradient is much faster than the scanning motion. This allows a perturbation solution. The basic solution corresponds to the stationary axisymmetric case, and the perturbation is based on a small scanning velocity. The advantage of seeking a perturbation solution is that the three‐dimensional flow is modeled by two sets of two‐dimensional equations which are presumably much more tractable than the original three‐dimensional equations. Numerical solutions are obtained. The solid‐liquid interface is determined by an iterative scheme. In the presence of the recirculating flow, the heat transfer becomes convection dominated. The absorbed laser energy is convected sideways so that a wider and shallower molten region is obta...
Loss of α3β1 integrin function results in an altered differentiation program in the mouse submandibular gland

Mammalian submandibular gland (SMG) development leads to the establishment of highly organized secretory acinar and nonsecretory ductal epithelial cells. The ability of maturing salivary epithelial cells to attain their differentiated state has been shown to depend, in part, on interactions between extracellular matrix (ECM) proteins and their integrin receptors. In a search for key regulators of salivary cell lineage, we have studied α3β1 integrin, a receptor for the basement membrane protein laminin, by characterizing embryonic day 18 (E18) SMGs isolated from mice carrying a targeted mutation in the α3 integrin gene. Transmission electron microscopy studies showed that the mutant SMGs exhibited an aberrant differentiation phenotype with defects in the apical-basal polarity axis and in the basement membrane. Based on immunohistochemistry and Western blot analyses, the α3β1-deficient SMGs had altered expression and/or localization of several ECM and adhesive molecules, including laminin β1, fibronectin, α5 integrin, and E-cadherin. These changes correlated with alterations in the activation state of Ras-extracellular signal-regulated kinase (ERK), as well as the expression and/or localization of Cdc42 and RhoA, two Rho GTPases that regulate the organization of the actin cytoskeleton. We conclude that α3β1 is required for normal salivary cell differentiation and that its absence affects multiple components of adhesive complexes and their associated signalling pathways. © 2001 Wiley-Liss, Inc.
Identification and counting of asbestos fibers.

A combined analytical electron microscopic/optical count method for the determination of airborne asbestos fibers was tested for precision and bias. A modified phase contrast microscopic count method (NIOSH Method 7400) was used to determine total fiber content. The analytical electron microscope (AEM) procedure was added to identify the fraction of amosite asbestos fibers in airborne, laboratory-generated samples containing amosite and wollastonite fibers. Then this fraction was applied to the routine optical counts of all the samples in the set to estimate the asbestos fiber concentration. The effects of sample to sample, wedge to wedge, within wedge and between counter variability were examined. In addition, the variabilities of the elemental ratio within a fiber and between fibers was also determined to find their possible influence on the ability to identify the fiber as amosite in the presence of other silicate fibers. A precision of 20.1% relative standard deviation (RSD) and a bias of −9.1% for th...
Harnessing Multicore Processors for High-Speed Secure Transfer

A growing need for ultra-high-speed data transfers has motivated continued improvements in the transmission speeds of the physical network layer. As researchers develop protocols and software to operate over such networks, they often fail to account for security. The processing power required to encrypt or sign packets of data can significantly decrease transfer rates, and thus security is often sacrificed for throughput. Emerging multicore processors provide a higher ratio of CPUs to network interfaces and can, in principle, be used to accelerate encrypted transfers by applying multiple processing and network resources to a single transfer. We discuss the attributes that network protocols and software must have to exploit such systems. In particular, we study how these attributes may be applied in the GridFTP code distributed with the globus toolkit. GridFTP is a well-accepted and robust protocol for high-speed data transfer. It has been shown to scale to near-network speeds. While GridFTP can provide encrypted and protected data transfers, it historically suffers transfer performance penalties when these features are enabled. We present configurations to the Globus GridFTP server that can achieve fully encrypted high-speed data transfers.
Content-based searching of multimedia databases by use of approximate digital signatures

We propose the use of approximate digital signatures of selected multimedia feature vectors for fast content-based retrieval in large multimedia databases. We adapt and extend the approximate message authentication code (AMAC), introduced by some of the authors recently in the area of message authentication, to the multimedia searching problem. An AMAC is a binary signature with the ability to reflect changes in the message it represents. The Hamming distance between two AMACs is used to measure the degree of the similarity between multimedia objects. We develop a method to compress AMAC signatures to create a direct look-up table that allows for fast searching of a database. The color histogram is used as the example feature space to show how the signature is applied. Experimental results show that the performance of the proposed method is comparable with existing methods based on other popular metrics, but it significantly decreases search time.
Simple Bayesian Inference for Qualitative Political Research

In political science and related disciplines in the social and behavioral sciences, there exists an unfortunate de facto divide between qualitative and quantitative empirical research. Sometimes this divide is purely a function of training and disciplinary socialization, but often it reflects a valid dispute over the philosophical foundations of inquiry. I argue here that the Bayesian approach to quantitative empirical modeling is an amenable starting point for building a rapprochement between qualitative and quantitative research, and I introduce as an example a straightforward model that allows for the Bayesian estimation of the difference between means of very small samples with unknown and possibly unequal variances. I then extend this approach to consider nonnormal variates, informative priors, and a multivariate test of the difference of means useful for the researcher who is interested in determining whether two small samples are different on several dimensions simultaneously.
Gravity in the dynamical approach to the cosmological constant

One of the most disturbing difficulties in thinking about the cosmological constant is that it is not stable under radiative corrections. The feedback mechanism proposed by Mukohyama and Randall is a dynamical way to protect a zero or small cosmological constant against radiative corrections.Hence, while this by itself does not solve the cosmological constant problem,it can help in solving the problem. In the present paper we investigate stability and gravity in this approach and show that the feedback mechanism is both classically and quantum mechanically stable and has self-consistent, stable dynamics.