cssi/SciSciGPT-SciSciNet huggingface dataset:
Crystal Streak Camera

A high speed optical deflection system has been designed for picosecond laser pulse diagnostics. Evaluation of a prototype system indicates that an ultracompact streak camera with picosecond resolution can be constructed from readily available components with a relatively low cost. A commercially available electro-optic beam deflector with a 2-mm aperture ADP crystal is used in the prototype. This unit is capable of deflecting wavelengths from the visible to 1.06 pm. When high power single picosecond pulses are used, previous limitations of electro-optic deflectors due to signal beam absorption, internal heating, and mechanical shock waves are overcome. At 532 nm, a resolution of 18 spot diameters is obtained, while the dynamic range in excess of 200 is limited by the readout system. Use of a crystal material with a much higher electro-optic coefficient produces a theoretical resolution c,omparable to that of electro-optic cameras. The high current required to drive the crystal presents some difficult electronics problems and available solutions are discussed. Readout is accomplished with film, a TV camera, or a linear diode array. Computer manipulation of the output data can be used to improve resolution and dynamic range.
Detecting editorial bias in medical publishing

As publications are the principal method of distributing research, journal editors serve as the gatekeepers of emerging knowledge. Here, we provide a "case---control study" to examine the role of editorial bias in the New England Journal of Medicine, a major medical journal, by investigating author demographics of case reports that are either under editorial or meritorious selection. Our results indicate that editorial bias promoting the publication of authors from select high performance countries is declining, although there is increasing editorial preference for university-based authors. These findings are relevant to efforts aiming to increase transparency in scientific publishing.
Categorically Distinct Acute Stressors Elicit Dissimilar Transcriptional Profiles in the Paraventricular Nucleus of the Hypothalamus

The paraventricular hypothalamic nucleus (PVH) is a key site for integrating neuroendocrine, autonomic, and behavioral adjustments to diverse homeostatic challenges, including “physiological” (e.g., infection or hemorrhage) and “emotional” [e.g., restraint (RST) or footshock] stresses. Both types of challenges ultimately converge to activate common response systems represented in PVH, including the hypothalamo–pituitary–adrenal axis and the sympathoadrenal system. Oligonucleotide microarrays (U74A; Affymetrix, Santa Clara, CA) were used to compare and contrast gene expression profiles in the PVH elicited at 1 and 3 hr after acute exposure to representative physiological [intraperitoneal injection of 10 μg lipopolysaccharide (LPS)] and emotional (30 min RST) stressors. In general, the two challenges recruited relatively few genes in common, with the degree of overlap varying across functional classes of genes. The greatest degree of commonality was seen among signaling molecules and neuropeptides, whereas transcription factors upregulated by RST and LPS were largely distinct. Unexpectedly, RST induced a number of immune-related molecules, which were not regulated by LPS. Hybridization histochemical analyses localized a subset of responsive transcripts to the PVH and/or immediately adjoining regions. Immunerelated molecules in particular distributed broadly to vascular and other barrier-associated cell types. These global transcriptional profiles inform the search for early (transcription factors) and late (target genes) mechanisms in the modulation of PVH, and generalized CNS, responses to categorically distinct stressors.
Renal Cellular Transport, Metabolism, and Cytotoxicity of S-(6-Purinyl)glutathione, a Prodrug of 6-Mercaptopurine, and Analogues

Abstract The disposition of S -(6-purinyl)glutathione (6-PG) and its metabolites, including the antitumor agent 6-mercaptopurine (6-MP), was characterized in freshly isolated renal cortical cells from male F344 rats to assess the ability of the kidney to convert 6-PG to 6-MP. The intracellular transport and accumulation of 6-PG and 6-MP, the metabolism of 6-PG to 6-MP, and the potential cytotoxicity of 6-MP, 6-thioxanthine (6-ThXan), and 6-thioguanine (6-ThGua) were determined. 6-PG and 6-MP were accumulated by renal cortical cells by time- and concentration-dependent processes, reaching maximal levels of 14.2 and 1.52 nmol/10 6 cells, respectively, with 1 mM concentrations of each compound. Treatment with acivicin, an inhibitor of 6-PG metabolism by γ-glutamyltransferase, increased accumulation of 6-PG, and treatment with α-keto-γ-methiolbutyrate, a keto acid cosubstrate that stimulates activity of the cysteine conjugate β-lyase (β-lyase), which generates 6-MP, decreased accumulation of 6-PG. Incubation of renal cells with 10 mM 6-PG generated 6-MP at a rate of 2.4 nmol/min per 10 6 cells, demonstrating that the β-lyase pathway forms the desired product from the prodrug within the intact renal cell. Preincubation of cells with acivicin or aminooxyacetic acid, an inhibitor of the β-lyase, decreased the net formation of 6-MP, demonstrating further the function of the β-lyase. 6-MP, 6-ThXan, and 6-ThGua exhibited approximately equivalent cytotoxicity (45–55% release of lactate dehydrogenase with 1 mM at 2 hr) in isolated renal cells. Based on the known antitumor potency of these agents, this suggests that cytotoxicity and antitumor activity occur by distinct mechanisms. The high amount of accumulation of 6-PG and its subsequent metabolism to 6-MP, as compared with the relatively low amount of accumulation of 6-MP, in renal cells suggest that 6-PG can function as a prodrug and is a more effective delivery vehicle for 6-MP to renal cells than 6-MP itself. Administration of 6-PG may be an effective means of treating renal tumors or suppressing renal transplant rejection.
Cannabinoid CB1 receptor-mediated inhibition of prolactin release and signaling mechanisms in GH4C1 cells.

The GH4C1 cell line was used to study the cellular mechanisms of cannabinoid-mediated inhibition of PRL release. Cannabinoid CB1 receptor activation inhibited vasoactive intestinal polypeptide- and TRH-stimulated PRL release, but not its basal secretion. The cannabinoid-mediated inhibition of TRH-stimulated PRL release was reversed by the CB1 receptor-specific antagonist, SR141,716A, and was abolished by pertussis toxin pretreatment, indicating that Gα subunits belonging to the Giα and Goα family were involved in the signaling. Photoaffinity labeling using[α -32P]azidoaniline GTP showed that cannabinoid receptor stimulation in cell membranes produced activation of four Gα subunits (Giα2, Giα3, Goα1, and Goα2), which was also reversed by SR141,716A. The CB1 receptor agonists, WIN55,212–2 and CP55,940, inhibited cAMP formation and calcium currents in GH4C1 cells. The subtypes of calcium currents inhibited by WIN55,212–2 were characterized using holding potential sensitivity and calcium channel blockers. WIN...
Case-based reasoning and its implications for legal expert systems

Reasoners compare problems to prior cases to draw conclusions about a problem and guide decision making. All Case-Based Reasoning (CBR) employs some methods for generalizing from cases to support indexing and relevance assessment and evidences two basic inference methods: constraining search by tracing a solution from a past case or evaluating a case by comparing it to past cases. Across domains and tasks, however, humans reason with cases in subtly different ways evidencing different mixes of and mechanisms for these components. In recent CBR research in Artificial Intelligence (AI), five paradigmatic approaches have emerged: statistically-oriented, model-based, planning/design-oriented, exemplar-based, and adversarial or precedent-based. The paradigms differ in the assumptions they make about domain models, the extent to which they support symbolic case comparison, and the kinds of inferences for which they employ cases. Reasoning with cases is important in legal practice of all kinds, and legal practice involves a wide variety of case-based tasks and methods. The paradigms' respective benefits and costs suggest different approaches for different legal tasks. CBR research and development in the field of AI and Law should be pursued vigoriously for several reasons. CBR can supplement rule-based expert systems, improving their abilities to reason about statutory predicates, solve problems efficiently, and explain their results. CBR can also contribute to the design of intelligent legal data retrieval systems and improve legal document assembly programs. Finally, in cognitive studies of various fields, it can model methods of transforming ill-structured problems into better structured ones through the use of case comparisons.
Minimum metallic conductivity of fluid hydrogen at 140 GPa (1.4 Mbar)

Electrical conductivity measurements indicate that fluid hydrogen achieves the minimum conductivity of a metal at 140 GPa, ninefold initial liquid-${\mathrm{H}}_{2}$ density, and 2600 K. Metallization density is defined to be that at which the electronic mobility gap ${E}_{g}$ is reduced by pressure to ${E}_{g}\ensuremath{\sim}{k}_{B}T,$ at which point ${E}_{g}$ is filled in by fluid disorder to produce a metallic density of states with a Fermi surface and the minimum conductivity of a metal. High pressures and temperatures were obtained with a two-stage gun, which accelerates an impactor up to 7 km/sec. A strong shock wave is generated on impact with a holder containing liquid hydrogen at 20 K. The impact shock is split into a shock wave reverberating in hydrogen between two stiff ${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ anvils. This compression heats hydrogen quasi-isentropically to about twice its melting temperature and lasts \ensuremath{\sim}100 ns, sufficiently long to achieve equilibrium and sufficiently short to preclude loss of hydrogen by diffusion and chemical reactions. The measured conductivity increases four orders of magnitude in the range 93 to 140 GPa and is constant at 2000 (\ensuremath{\Omega} ${\mathrm{c}\mathrm{m})}^{\mathrm{\ensuremath{-}}1}$ from 140 to 180 GPa. This conductivity is that of fluid Cs and Rb undergoing the same transition at 2000 K. This measured value is within a factor of 5 or less of hydrogen conductivities calculated with (i) minimum conductivity of a metal, (ii) Ziman model of a liquid metal, and (iii) tight-binding molecular dynamics. At metallization this fluid is \ensuremath{\sim}90 at. % ${\mathrm{H}}_{2}$ and 10 at. % H with a Fermi energy of \ensuremath{\sim}12 eV. Fluid hydrogen at finite temperature undergoes a Mott transition at ${D}_{m}^{1/3}{a}^{*}=0.30,$ where ${D}_{m}$ is the metallization density and ${a}^{*}$ is the Bohr radius of the molecule. Metallization occurs at a lower pressure in the fluid than predicted for the solid probably because crystalline and orientational phase transitions in the ordered solid do not occur in the fluid and because of many-body and structural effects. Tight-binding molecular dynamics calculations by Lenosky et al. suggest that fluid metallic hydrogen is a novel state of condensed matter. Protons are paired transiently and exchange on a timescale of a few molecular vibrational periods, $\ensuremath{\sim}{10}^{\ensuremath{-}14}\mathrm{sec}.$ Also, the kinetic, vibrational, and rotational energies of the dynamically paired protons are comparable.
Slow-waves in the olfactory system: an olfactory perspective on cortical rhythms

Over the past few years, it has become clear that oscillatory dynamics of cortical networks are closely involved in sensory coding, attention, memory and sleep. Although most experimental and theoretical studies have focused on the neocortex, we believe that progress in understanding cortical oscillations can be advanced by also considering the olfactory system – which shares many basic properties with the neocortex and shows similar oscillatory patterns. Besides offering the advantage of a greater experimental tractability, the olfactory cortex might prove to be instrumental in uncovering general functional principles of neocortical oscillations, by virtue of the potentially important role of olfaction during neocortical evolution. In this article, we illustrate how such an evolution-based comparative approach can provide novel insights into neocortical slow-wave sleep oscillations and their relationship to respiration.
The transition from dislocation climb to viscous glide in creep of solid solution alloys

Abstract There are two distinct and separate classes of creep behavior in metallic solid solution alloys. The mechanism of creep in Class I alloys appears to be some form of dislocation climb process, whereas the mechanism in Class II alloys appears to be a viscous glide process. By making assumptions concerning the nature of the climb and glide processes, and using existing experimental results for an Al-3% Mg alloy, it is shown that, to a, first approximation, the criterion for deformation by viscous glide is given by Bσ 2 k 2 (1 − v γ Gb 3 > T 2 e 2 cb 6 where B ∼ 8 × 1012, σ is the applied stress, k is Boltzmann's constant, v is Poisson's ratio, γ is the stacking fault energy, G is the shear modulus, b is the Burgers vector, T is the absolute temperature, e is the solute-solvent size difference, and c is the concentration of solute atoms. The creep behavior of twenty-eight different solid solution alloys is analyzed, and it is shown that all alloys except one (Au-10% Ni) give results which are consistent with this criterion for viscous glide.
Depression, Suicide, Tobacco Control Policies, and Cigarette Smoking Among High School Students

This article is concerned with the differential impact of real pecuniary prices and youth access laws on the smoking behavior among depressed and suicidal youth. Previous cross-sectional research on adolescents has a found a strong positive relationship between cigarette-smoking and depression. This article attempts to fill a void in this literature by examining the economic determinants of cigarette demand among high school students in the United States who exhibit depressive symptoms. The data for this study were extracted from 1991, 1993, 1995, 1997, 1999 and 2001 National School-Based Risk Behavior surveys of high school students conducted by the Centers for Disease Control and Prevention. The overall price elasticity of demand was −0.899 for youths who had suicidal thoughts, −0.837 for youths who had planned suicide and −0.162 for youths who had attempted suicide. These estimates tend to be less elastic than elasticity estimates for non-suicidal youth.
Hybridization Between Classroom and On-Line Teaching: An Alternative Teaching Approach

Though face to face class is still a dominant-teaching approach in most higher educational institutes, with the development of internet technology, on-line teaching has been increasingly popular. This paper intends to share experiences, myths, and lessons that the authors have learned during exploration of hybridization between classroom and on-line teaching of an undergraduate course in the area of mechanical engineering. Several key factors have been used to determine effectiveness and efficiency of this blended teaching approach. The paper will also discuss how the hybridization takes advantage and avoids disadvantages of both traditional classroom teaching and on-line teaching. The hybridization approach is also compared with traditional classroom teaching. The current student survey and course assessment indicates that the approach provides a promising alternative for teaching an undergraduate course.Copyright © 2012 by ASME
Simulation of the environmental fate and transport of chemical signatures from buried land mines

The fate and transport of chemical signature molecules that emanate from buried landmines is strongly influenced by physical chemical properties and by environmental conditions of the specific chemical compounds. Published data have been evaluated as the input parameters that are used in the simulation of the fate and transport processes. A one- dimensional model developed for screening agricultural pesticides was modified and used to simulate the appearance of a surface flux above a buried landmine and estimate the subsurface total concentration. The physical chemical properties of TNT cause a majority of the mass released to the soil system to be bound to the solid phase soil particles. The majority of the transport occurs in the liquid phase with diffusion and evaporation driven advection of soil water as the primary mechanisms for the flux to the ground surface. The simulations provided herein should only be used for initial conceptual designs of chemical pre-concentration subsystems or complete detection systems. The physical processes modeled required necessary simplifying assumptions to allow for analytical solutions. Emerging numerical simulation tools will soon be available that should provide more realistic estimates that can be used to predict the success of landmine chemical detection surveys based on knowledge of the chemical and soil properties, and environmental conditions where the mines are buried. Additional measurements of the chemical properties in soils are also needed before a fully predictive approach can be confidently applied.
Evaluation of levamisole as a feed additive for growth and health management of hybrid striped bass (Morone chrysops × Morone saxatilis)

Abstract Three separate experiments were conducted with juvenile hybrid striped bass to determine the effects of levamisole as a feed supplement on growth performance, innate immunity and specific antibody responses, as well as resistance to Streptococcus iniae and Aeromonas hydrophila infection. A basal diet was formulated to contain 40% protein, 10% lipid and an estimated digestible energy level of 3.5 kcal/g. Four levels (100, 250, 500 and 1000 mg/kg) of levamisole were added to the basal diet in place of cellulose. After the 3-week feeding period in feeding trial 1, enhanced weight gain was generally observed in fish fed the diets supplemented with a low level ( P P S. iniae and A. hydrophila were not proven after two separate 3-week feeding trials and disease challenges in the present study. Agglutinating antibody titers of individual fish were highly varied and not significantly influenced by dietary levamisole at the tested levels.
Visualization of solute migration in chromatographic columns Influence of the frit porosity

The dual-perspective, on-column detection method previously described was used to observe the effects of the inlet frit on the profiles of chromatographic bands. Visualization of bands of iodine was achieved by injecting its dilute solutions in carbon tetrachloride into a glass column packed with a C18-bonded silica and eluted with carbon tetrachloride, which has the same refractive index as the packing material. The bands were photographed on-column with two standard 35-mm SLR cameras oriented at right angle. The photographs were scanned and the digitized images of the sample bands analyzed with proper software. A number of columns, as similar as possible, were fitted with different 2- and 10-microm porosity stainless steel frits. Subsequent analysis of the digitized band images revealed irregularities in the band shape resulting from frit contributions to band dispersion. The 2-microm frits produced more dramatic effects overall than the coarser frits. Local axial dispersion coefficient values, expressed as local reduced plate height, were calculated. The results demonstrate the possibly damaging effects of the frit on the band shape.
The effect of storage of blood on mononuclear cell antibody-dependent cellular cytotoxicity to herpes simplex virus-infected cells

Antibody-dependent cellular cytotoxicity (ADCC) activity to herpes simplex virus-infected cells of fresh mononuclear cells was compared with the ADCC activity of mononuclear cells obtained from blood after 1, 2, and 18 hr of storage at room temperature. After 1 and 2 hr of blood storage, mononuclear cell ADCC activity decrease significantly (P less than 0.05 and P less than 0.01, respectively) and was undetectable after 18 hr of storage. The use of preservative-free heparin and various effector to target cell ratios further verified these results. There was no significant difference between natural killer cytotoxicity of mononuclear cells obtained from fresh blood compared with that obtained from blood after 1 and 2 hr of storage. These data demonstrate the importance of rapid assay of clinical specimens utilized to determine differences in ADCC activity of patient populations.
Whipple's disease, genomics, and drug therapy.

The recent articles concerning the release of the genome for Tropheryma whipplei [1, 2], the causative agent of Whipple's disease, anticipate new medical discoveries and conclusions that will be drawn from the decoding of the genome. Although the reports mention that genes for key metabolic processes were missing, we were nevertheless surprised to find that the genome does not contain the coding sequence for dihydrofolate reductase (DHFR). This is significant because competitive inhibition of DHFR by trimethoprim is the mode of action of this antibacterial agent. Lacking an adequate population for clinical studies, retrospective analyses and patient series ([3, 4] references therein) have concluded that the drug combination of trimethoprim and sulfamethoxazole are the preferred treatment regimes. The treatment goal is to disrupt purine and pyrimidine synthesis, and hence replication, by shutting down tetrahydrofolate biosynthesis. However, while the use of trimethoprim will affect the host, thereby indirectly affect the bacterium through a reduced tetrahydorfolate pool, it is unlikely that trimethoprim has any effect on tetrahydrofolate production in T. whipplei. To be sure that there weren't any weak homologues to DHFR or that the DHFR gene was somehow missed due to being part of a multi-functional enzyme, we performed a sequencemore » search (TBLASTN) of the T. whipplei genome using the DHFR protein sequence from the fellow actinomycete, Mycobaterium tuberculosis, as the target sequence. No close or distant homologues were found. While some bacterial plasmids code for a type II DHFR that has no homology to the more common type I DHFR found in most species, type II DHFR does not bind trimethoprim and tetrahydrofolate production is unaffected by the presence of trimethoprim. Furthermore, the genome additionally lacks a gene for thymidylate synthetase, another key enzyme in the folate-one carbon pathway that utilizes the DHFR product tetrahydrofolate. Lacking randomized double-blind trials of various antibiotic regimes, the scientific study of T. whipplei and its genome is increasingly important for the development of an effective therapy.« less
Analysis of Alcohols in Essential Oils of Grapefruit, Lemon, Lime, and Tangerine

SUMMARY Alcohols in the cold-pressed essential oils of grapefruit, lemon, lime, and tangerine were extracted from the whole oil with glycerol, isolated by column chromatography, separated by gas chromatography, and identified by infrared and mass spectroscopy. Nineteen alcohols were identified in grapefruit oil, 9 in lemon, 8 in lime, and 16 in tangerine. In addition, the fungicide, o-phenyl phenol, was found in the oils of grapefruit and tangerine.
Diversification and host switching in avian malaria parasites

The switching of parasitic organisms to novel hosts, in which they may cause the emergence of new diseases, is of great concern to human health and the management of wild and domesticated populations of animals. We used a phylogenetic approach to develop a better statistical assessment of host switching in a large sample of vector-borne malaria parasites of birds (Plasmodium and Haemoproteus) over their history of parasite-host relations. Even with sparse sampling, the number of parasite lineages was almost equal to the number of avian hosts. We found that strongly supported sister lineages of parasites, averaging 1.2% sequence divergence, exhibited highly significant host and geographical fidelity. Event-based matching of host and parasite phylogenetic trees revealed significant cospeciation. However, the accumulated effects of host switching and long distance dispersal cause these signals to disappear before 4% sequence divergence is achieved. Mitochondrial DNA nucleotide substitution appears to occur about three times faster in hosts than in parasites, contrary to findings on other parasite-host systems. Using this mutual calibration, the phylogenies of the parasites and their hosts appear to be similar in age, suggesting that avian malaria parasites diversified along with their modern avian hosts. Although host switching has been a prominent feature over the evolutionary history of avian malaria parasites, it is infrequent and unpredictable on time scales germane to public health and wildlife management.
Self-Reported Racial Discrimination and Substance Use Among Asian Americans in Arizona

We examined associations between different forms of self-reported racial discrimination and current substance use (i.e., smoking, alcohol use, and controlled substance use) among Asian Americans living in Arizona. The data are from 271 Asian American adults participating in the 2008 Asian Pacific Arizona Inititative (APAZI) Survey, which is part of a larger collaboration between community members, organizational leaders, and researchers. Asian Americans treated like they were not American because of their race were at increased risk of tobacco use, after controlling for covariates, including age, gender, education, family income, health insurance, nativity status, and language, and other types of racial discrimination. Also, individuals treated differently because of their race were at increased risk of alcohol use and controlled substance use, after controlling for covariates and other types of racial discrimination. The results indicate that Asian Americans experience a wide range of racial discrimination types and some forms of racial discrimination may have greater associations with tobacco, alcohol, and controlled substance use than others.
Fatty acid contents of certain processed foods

Fatty acid constituents of two cheeses, four cured meats, and two hydrogenated oils were determined; two sets of data were obtained for each sample. Unsaturated acids were determined spectrophotometrically in the total fatty acids prepared from each fat, and saturated and unsaturated components were determined chemically and spectrophotometrically on each fraction obtained from distilling the methyl esters prepared from the fats. Close agreement was obtained between the percentages of unsaturated components found in distilled and non-distilled samples. Methyl esters of cheese fats were prepared without prior distillation of steam-volatile acids; no separation of saturated and unsaturated components was made on any sample. Fatty acid components were also converted to percent of each fatty acid in each food.
Microbial Identification by GLC

Abstract Laboratories offering comprehensive or specialized diagnostic microbiology services can complement other technology and enhance their capabilities for microbial identification by GLC. The main enticement of GLC is the versatility with which it can be applied. Except for the initial cost of capital equipment. expenses are modest. The specific applications employed by a given laboratory must be individualized, but GLC has considerable power as a tool in aiding the identification of nonfermentative and miscellaneous gram-negative bacilli, anaerobes, and mycobacteria. Applications that are more highly specialized—e.g., identification of un-usual or newly encountered pathogens, fastidious organisms, and atypical strains—are additional considerations for those laboratories engaged in such work.
Optimal step-by-step restoration of distribution systems during excessive loads due to cold load pickup

Abstract Restoration of a distribution system following extended outages may cause problems if the substation transformer capacity cannot supply the initial load. Excessive initial load is a result of loss of diversity in the distribution system. Dividing the system into sections and restoring these sections step by step is one of the solutions to overcome excessive load due to cold load pickup. In step-by-step restoration, the order of restoration of sections becomes an important factor in increasing the reliability and decreasing the average customer interruption duration. In this paper, step-by-step restoration of a distribution system to utilize transformer capacity to the maximum extent and to minimize the customer interruption duration is studied.
Thermodynamics of translational crack layer propagation

Recognizing that fracture in many materials propagates as a crack preceded by intensive damage, a theory is presented to model the crack and the preceding damage as a single thermodynamic entity, i.e., a crack layer (CL). The active zone of the CL may propagate by translational, rotational, expansional and/or distortional movements. Concepts of irreversible thermodynamics are employed to derive the law of CL propagation by translational mode as: $$\dot l = \frac{{\beta J_1 \left\langle d \right\rangle }}{{\gamma ^ * R_1 - J_1 }}$$ wherei is the rate of CL translation,β is a dissipative coefficient,J 1 is the energy release rate, 〈d〉 is a characteristic size of the active zone, γ* is the specific enthalpy of damage andR 1 is the translational resistance moment. This expression describes the entire history of CL propagation. Experimental results on fatigue crack propagation in polystryrene are in good agreement with the proposed formalism.
Causality violation in spatially closed space-times

Some results are obtained which establish conditions under which causality violation cannot occur in space-times admitting a compact, but not necessarily acausal, spacelike hypersurface. For example, it is shown that causality violation can occur in a space-time admitting a compact spacelike slice and obeying fairly reasonable energy conditions only if it is “singular” in the sense that some “causal interval”J+(p) ∩J−(q) has noncompact closure.
Isolation of a Golgi apparatus-rich fraction from rat liver. IV. Thiamine pyrophosphatase.

The thiamine pyrophosphatase (the enzyme [s] catalyzing the release of inorganic phosphate with thiamine pyrophosphate as the substrate) activities of Golgi apparatus-, plasma membrane-, endoplasmic reticulum-, and mitochondria-rich fractions from rat liver were compared at pH 8. Activity was concentrated in the Golgi apparatus fractions, which, on a protein basis, had a specific activity six to eight times that of the total homogenates or purified endoplasmic reticulum fractions. However, only 1–3% of the total activity was recovered in the Golgi apparatus fractions under conditions where 30–50% of the UDPgalactose:N-acetylglucosamine-galactosyl transferase activity was recovered. Considering both recovery of galactosyl transferase and fraction purity, we estimate that approximately 10% of the total thiamine pyrophosphatase activity of the liver was localized within the Golgi apparatus, with a specific activity of about ten times that of the total homogenate. Cytochemically, reaction product was found in the cisternae of the endoplasmic reticulum as well as in the Golgi apparatus. This is in contrast to results obtained in most other tissues, where reaction product was restricted to the Golgi apparatus. Thus, enzymes of rat liver catalyzing the hydrolysis of thiamine pyrophosphate, although concentrated in the Golgi apparatus, are widely distributed among other cell components in this tissue.
Extracorporeal Membrane Oxygenation Induced Cardiac Dysfunction in Newborn Lambs

Extracorporeal membrane oxygenation (ECMO) is routinely used to support cardiopulmonary failure in infants and children. Suboptimal outcomes for primary cardiac support suggest a need for investigation of the impact of ECMO on the heart. Twenty-four newborn lambs received a brief period of ECMO support to investigate the hypothesis that ECMO produces cardiac dysfunction in newborn lamb. Dorset newborn lambs, 4–7 days of age, were exposed to ECMO for 5 min at a 100 ml/kg flow rate and quickly weaned off. Measurements included echocardiographic mean left ventricular (LV) velocity of circumferential fiber shortening corrected for heart rate (mVCFc), LV shortening fraction, and peak systolic wall stress plus hemodynamic measurement of LV maximum rate of pressure change with time (LV dp/dt max), maximum rate of pressure change divided by developed pressure (LV dp/dtP), right atrial pressure, pulmonary capillary wedge pressure, mean pulmonary artery pressure, LV peak and end-diastolic pressure, and aortic pressure. These measures were also obtained after an exposure to 5 min of ECMO and immediate disconnect for 5 min, followed by ECMO administration for 1 h again, followed by discontinuation of ECMO. LV mVCFc is decreased after exposure to 5 min of ECMO support despite a decrease in LV peak systolic wall stress that provides afterload reduction. LV mVCFc is inversely related to peak systolic wall stress at a significance level of p < 0.0001. The time period after initiation of ECMO is a significant factor in the model (p = 0.0097). Time [baseline] was different from the other time points with p = 0.0010. Average mVCFc at baseline is 1.27 ± 0.35 and decreases to 1.01 ± 0.42 after 5 min of ECMO that is then withdrawn. Peak systolic wall stress decreases from 36.0 ± 13.1 at baseline to 29.8 ± 12.1 after 5 min of ECMO. LV dp/dt max decreases from 1,769 ± 453 mmHg/s at baseline to 1,311 ± 513 mmHg/s after exposure to 5 min of ECMO (p = 0.0005). Baseline LV dp/dt max is different from each point after start of ECMO. Diastolic LVdp/dt min increased from −1,340 ± 477 mmHg/s to −908 ± 393 mmHg/s at 5 min. Echocardiographic mVCFc, when considered in isolation or as a function of LV peak systolic wall stress, shows diminished LV function after ECMO. Hemodynamic measurement of LV dp/dt max and LV dp/dt min confirms the observation. Separation of the humoral from mechanical effect of ECMO with the short exposure to the extracorporeal circuit shows that an immediate decrement of LV function occurs at initiation of ECMO, a finding that has not been stressed with previous studies of extracorporeal support. This implies a potentially outcome-limiting deleterious effect for the patient who requires ECMO support for the heart rather than the lungs. We should continue to strive to understand and ameliorate this deleterious effect of the extracorporeal circulation circuit.
Alamar Blue Discloses Latent Toxicity of Vesicant in Human Epidermal Model and Cells

AbstractA new metabolic activity indicator, alamar blue (AB), was used to estimate cell counts and to observe toxicity in the same human cells at several time points. AB permitted accurate estimates of cell numbers as low as 500 cells per well when AB was incubated with normal human epidermal keratinocytes (NHEK) for 30 min. AB was used as a noninvasive fluorescent probe to analyze toxic effects of CEES (2-chloroethylethyl sulfide), an alkylating agent and vesicant. Dose-dependent effects of 2 hr CEES or Triton X-100 exposures on confluent NHEK monolayers were revealed 4 hr postexposure, after 2 hr incubations with AB. Effects of CEES or Triton X-100 on a synthetic human epidermal model (EpiDerm) were demonstrated at 4, 24, and 48 hr postexposure. EpiDerm samples were nonviable at 4 hr after initiation of 80 mM CEES exposures, but a similar effect was delayed until 48 hr after 8.0 and 0.8 mM CEES or 1% (v/v) Triton X-100 exposures. Histologic examination of the latter EpiDerm specimens revealed complete s...
Parylene-encapsulated copolymeric membranes as localized and sustained drug delivery platforms

Parylene is a biologically inert material capable of being deposited in conformal nanoscale layers on virtually any surface, making it a viable structural material for the fabrication of drug delivery devices, as well as implant coatings, sensors, and other biomedical technologies. Here we explore its novel drug delivery applications by using parylene to package the polymethyloxazoline-polydimethylsiloxane-polymethyloxazoline (PMOXA-PDMS-PMOXA) block copolymer membrane of a nanoscale thickness (~4 nm/layer) mixed with a therapeutic element, creating an active parylene-encapsulated copolymeric (APC) membrane for slow release drug delivery of dexamethasone (Dex), a potent anti-inflammatory and immunosuppressant synthetic glucocorticoid. Given current needs for localized therapeutic release for conditions such as cancer, post-surgical inflammation, wound healing, regenerative medicine, to name a few, this stand-alone and minimally invasive implantable technology may impact a broad range of medical scenarios. To evaluate the applicability of the APC membrane as a biocompatible drug delivery system, real-time polymerase chain reaction (RT-PCR) was performed to investigate the expression of cytokines that regulate cellular stress and inflammation as a result of in vitro RAW264.7 macrophage cell growth on the APC membrane. Significant decreases in relative mRNA levels of IL-6, TNF-α, and iNOS were observed. Dex functionalized APC membranes were further found to effectively slow-elute the drug via confocal microscopy, with a confirmed extended elution capability over a period of several days, undergoing phosphate buffered saline washes between time points. In addition, we examined the membrane surface through atomic force microscopy (AFM) to examine Dex/copolymer deposition, and to characterize the surface of the APC membrane. Furthermore, we evaluated the effects of incubation with the APC membrane in solution on macrophage growth behavior and cellular adhesion, including the physical properties of parylene and the copolymer to elucidate the anti-adhesive responses we observed. The results of this study will provide insight into ultra-thin and flexible devices of parylene-encapsulated copolymer membranes as platform drug delivery technologies capable of localized and precision therapeutic drug elution.
Macroeconomic Change and the Biopolitics of Health in Cuba's Special Period

El exito de Cuba en el campo de la salud publica a menudo se asocia a altos indices estadisticos alcanzados por la poblacion en muchas areas. Esto ha llevado a muchos estudiosos a hacer de la isla un "anti-modelo" de desarrollo. Sin embargo, los investigadores en esta linea de pensamiento caen en lo que yo llamo fetichismo estadistico. Esta forma de fetichismo tiene un objetivo especifico. Los indicadores basicos de salud en Cuba proporcionan un modelo de la realidad, pero no permiten el examen critico de lo que las cifras reflejan o como se obtienen. Este articulo propone el amplio examen de los procesos sociales, que moldean e influyen en el sistema primario de salud publica en Cuba. Concretamente, el trabajo examina como el colapso del bloque sovietico y el fortalecimiento del embargo por parte de los Estados Unidos estan cambiando la experiencia yla aceptacion que la poblacion tiene del sistema de salud.Ademas, el trabajo analiza como los cambios en la dinamica de las relaciones entre la poblacion y la burocracia medica han transformado tambien los modos en que el Estado ejerce y representa su poder de un modo mas sutil a traves de la imposicion de una disciplina fisica a nivel individual
Complementation between SV40 and RFV defectives and acquisition of SV40 origins by late RFV genomes

EL SV40 and RFV are variants of SV40 and BKV which contain bipartite or dual genomes. One molecule contains all the early viral sequences (E-SV40, E-RFV) and the other all the late viral sequences (L-SV40, L-RFV). Early and late genomes complement one another during productive infection. Experiments were designed to determine if E-genomes of one virus could complement L-genomes of another virus. If complementation did occur, intermolecular recombination events which lead to a more efficient infection or an altered host range might occur, and the sequences involved could than be identified. Two combinations were generated by direct transfection of BSC-1 green monkey cells. E-RFV and L-SV40 DNA complementation resulted in hybrid virus growth and cell killing. The hybrid demonstrated a narrow host range. Following serial passage, some E-RFV genomes contained SV40 origin region sequences but these recombinants did not overgrow prototype E-RFV genomes, even after many virus passages. In addition, no significant alterations in host range could be detected. Complementation between E-SV40 and L-RFV yielded a virus with a relatively wider host range. Virus growth and cell killing appeared very slowly at first. However, with each passage of E-SV40/L-RFV, cell killing occurred progressively more rapidly, until passage 7 when it became extensive in 7 days rather than 6-8 weeks. Infected cells contained 10-20 times more E-SV40 than L-RFV DNA during the first passage. However, by passage 7, both genomes were equally represented. During serial passage, L-RFV DNA acquired SV40 sequences from around the origin and the terminus of replication, such that recombinant (r) L-RFV genomes contained three SV40 origins [corrected] (including the 72-bp repeat) and 2 termini, and prototype L-RFV DNA was lost. E-SV40/rL-RFV demonstrated an altered host range propagating in some cell lines which did not support E-SV40/L-RFV growth. Both the host range change and the increased growth of rL-RFV genomes were shown to be at least partly caused by the acquisition of the SV40 sequences.
Transformative justice: survivor perspectives on clergy sexual abuse litigation

This paper examines the motivations of men and women who entered into mass tort litigation against the Catholic Church, primarily the Archdiocese of Boston, which alleged clergy sexual abuse by Roman Catholic priests. The study is based on in‐depth interviews with adult survivors of sexual abuse (perpetrated against boys and girls), and with their attorneys and other legal advocates. We explore the challenges faced by survivor‐litigants, as well as their accounts of the subjective experience and meaning of litigation. Our focus is on clarifying petitioners’ multiple objectives and illuminating some of the unanticipated ways in which participation in the case offered possibilities for positive, even transformative, outcomes. The study contributes to our understanding of the course and effects of litigation from the perspective of the litigants, and has important implications for the theoretical literature on the transformation of disputes.
Critical Multicultural Social Work, by Jose Sisneros, Catherine Stakeman, Mildred C. Joyner, & Catheryne E. Schmitz

“The study of diversity, as it is commonly practiced in social work, can be narrow and limiting… . Although difference is acknowledged, the difficult issues of power and domination are not addresse...
Control of nanoparticle size and agglomeration through electric-field-enhanced flame synthesis

The isolated study of electrophoretic transport of nanoparticles (that are innately charged through thermionic emission), with no ionic wind, has been conducted under uniform electric fields. Titania nanoparticles are produced using a burner-supported low-pressure premixed flame in a stagnation-point geometry from corresponding organometallic vapor precursor. The material processing flow field is probed in-situ using laser-induced fluorescence (LIF) to map OH-radical concentrations and gas-phase temperatures. The experimental results of particle growth under different applied electric fields are compared with computations using monodisperse and sectional models. The results show that such electric field application can decrease aggregate particle size (e.g. from 40 to 18 nm), maintain metastable phases and particle crystallinity, and non-monotonically affect primary particle size (e.g. from 6 to 5 nm) and powder surface area. A specific surface area (SSA) for anatase titania nanopowder of 310 m2/g, when synthesized under an applied electric field of 125 V/cm, is reported. Results are also given for the synthesis of alumina nanoparticles.
Modeling of muscle forces in humans with and without temporomandibular joint disorders.

Objectives Subjects with/without temporomandibular joint disorders (TMJD) were tested for differences in muscle forces.
An alternative approach to evaluating, measuring, and comparing domestic and international health institutions: Insights from social science theories

Abstract Objectives This article introduces the benefits of applying social science theories discussing institutional stasis and change to better measure, explain, and compare elite behavior within health administration and decentralization processes. A new comparative method based on these theories is introduced, as well as methods for collecting and analyzing data. Methods A literature review of health governance, health system governance, and path dependency and institutional change theory was conducted to reveal the limitations of health governance approaches explaining elite behavior. Next, path dependency and institutional change theory was applied to case studies in order to demonstrate their utility in explaining institutional stasis and change. Results Current approaches to analyzing and comparing elite behavior in the health governance frameworks are limited in their ability to accurately explain the willingness of elites to pursue more efficient institutional and policy designs. Current indicators measuring elite behavior are also too static, failing to account for periodic resistance to change and the conditions for it. Conclusions By applying path dependency and institutional change theory, the policy community can obtain greater insight into the willingness and thus capacity of institutions to pursue innovations while developing alternative analytic frameworks and databases that better measure and predict this process.
Barbital sensitivity in the young rat.

Summary Young rats were more sensitive to barbital than mature rats, as indicated by a lower ED 50 and shorter mean lag time. Duration of sleep did not vary between young and old animals. Plasma levels of barbital were lower in the young animals. These data indicated that young animal sensitivity is not due to increased absorption or decreased excretion of barbital. An ineffective blood brain barrier or an inherent sensitivity of the young animal appears to be involved.
Improving the dental office environment for the older patient

An awareness of some of the physiologic changes associated with the aging process have been described. The dental office physical and human environment capability for treating the older patient can be enhanced by using some of the adaptive techniques discussed. Consideration demonstrated to the elderly patient reflects favorably on both the profession of dentistry and the individual dental office.