cssi/SciSciGPT-SciSciNet huggingface dataset:
Haemodynamics of Different Configurations of a Left Subclavian Artery Stent Graft for Thoracic Endovascular Aortic Repair.

Objective Branched stent grafts represent a viable option for left subclavian artery (LSA) revascularisation in patients treated by thoracic endovascular aortic repair (TEVAR) for Zone 2 lesions. This study investigated the haemodynamic performance of different LSA branched stent graft configurations as potential determinants of thrombotic and stroke risks. Methods A three dimensional aortic arch geometry extracted from post-operative computed tomography images of a TEVAR patient using a single LSA branched aortic endograft was modified in silico to obtain ten potential LSA branched stent graft configurations: five down facing (0–5 – 10 mm aortic protrusion with 10–12 mm internal diameter), four curved (30–60° with antegrade/retrograde orientation), and one LSA orifice misalignment. The 0 mm down facing stent graft was considered base configuration. Computational fluid dynamic analyses were performed to identify differences in pressure, energy, and wall shear stress (WSS) based parameters. Results Total pressure drop and energy loss variations among configurations were not greater than 5 mmHg (6% of mean arterial pressure) and 5.7 mW (0.7% of cardiac power), respectively. Protrusions up to 5 mm created clinically insignificant flow disturbances. However, stent graft protrusions further into the aortic lumen created more complex haemodynamics, characterised by larger energy loss and more prominent flow recirculation. Protrusion greater than 5 mm into the lumen was associated with larger areas of elevated maximum WSS (>20 Pa) along the outer surface of the branched stent graft. Conclusion Arterial haemodynamic characteristics are affected by LSA branched stent graft configurations, with pressure drops and energy losses likely to be clinically insignificant. The length of the stent graft protrusion into the aortic lumen generated the largest haemodynamic variations in the aortic system. Protrusions up to 5 mm have smaller risk of potential thrombus generation. Conversely, larger protrusions into the aortic lumen showed more disturbed haemodynamics, suggesting a greater risk of potential thrombus formation, which may be clinically important over time.
Model vs. playback experiments: The impact of sensory mode on predator‐specific escape responses in saki monkeys

Although experimentally simulating predator presence helps improve sample sizes in studies of free‐ranging animals, few studies have examined whether auditory playbacks and visual models produce similar results. Additionally, it is unclear if anti‐predator strategies are specific to predator hunting styles in understudied Neotropical pitheciid primates, limiting what we can generalize about this phenomenon across this taxonomic order. We conducted predator simulation experiments to assess whether wild Rylands' bald‐faced saki monkeys (Pithecia rylandsi) recognize predators based solely on acoustic cues, exhibit predator‐specific responses to different predator types, and vary responses to presentations in different sensory modes. In our playback experiments, sakis had weak responses to non‐predator control vocalizations compared to jaguar growls and harpy eagle shrieks. In most predator playbacks, subjects' first glance corresponded to the direction from which simulated predators would typically attack (above vs. below). However, although sakis exhibited appropriate movement responses to harpy playbacks (i.e., descending canopy), they exhibited no clear movement patterns when presented with jaguar playbacks. In contrast, jaguar model experiments consistently elicited fast approaches, mobbing‐style responses, and long alarm calling bouts. Thus, if we had relied on playbacks alone, we might have concluded that sakis have only generalized responses to terrestrial ambush predators. In fact, in all variables measured (e.g., latency, number of calls, and response duration), models of both predator species elicited stronger reactions than playbacks. Results indicate that bald‐faced sakis can identify predators based solely on vocalizations, but do not exhibit predator‐specific escape responses to terrestrial predators based on acoustic cues alone. The differential response to playbacks and models calls into question the reliability of using acoustic‐only stimuli to assess the specificity of anti‐predator behavior to predator hunting styles in some primate species.
Rules for Rebels: The Science of Victory in Militant History

While we currently witness potential conflict between the United States and Iran, as well as rumblings with North Korea, the post-Cold War international environment continues to observe a sharp dec...
Stability of 2H- and 1T-MoS2 in the presence of aqueous oxidants and its protection by a carbon shell

Two-dimensional molybdenum disulfide (MoS2) is emerging as a catalyst for energy and environmental applications. Recent studies have suggested the stability of MoS2 is questionable when exposed to oxidizing conditions found in water and air. In this study, the aqueous stability of 2H- and 1T-MoS2 and 2H-MoS2 protected with a carbon shell was evaluated in the presence of model oxidants (O2, NO2−, BrO3−). The MoS2 electrocatalytic performance and stability was characterized using linear sweep voltammetry and chronoamperometry. In the presence of dissolved oxygen (DO) only, 2H- and 1T-MoS2 were relatively stable, with SO42− formation of only 2.5% and 3.1%, respectively. The presence of NO2− resulted in drastically different results, with SO42− formations of 11% and 14% for 2H- and 1T-MoS2, respectively. When NO2− was present without DO, the 2H- and 1T-MoS2 remained relatively stable with SO42− formations of only 4.2% and 3.3%, respectively. Similar results were observed when BrO3− was used as an oxidant. Collectively, these results indicate that the oxidation of 2H- and 1T-MoS2 can be severe in the presence of these aqueous oxidants but that DO is also required. To investigate the ability of a capping agent to protect the MoS2 from oxidation, a carbon shell was added to 2H–MoS2. In a batch suspension in the presence of DO and NO2−, the 2H–MoS2 with the carbon shell exhibited good stability with no oxidation observed. The activity of 2H–MoS2 electrodes was then evaluated for the hydrogen evolution reaction by a Tafel analysis. The carbon shell improved the activity of 2H–MoS2 with a decrease in the Tafel slope from 451 to 371 mV dec−1. The electrode stability, characterized by chronopotentiometry, was also enhanced for the 2H–MoS2 coated with a carbon shell, with no marked degradation in current density observed over the reaction period. Because of the instability exhibited by unprotected MoS2, it will only be a useful catalyst if measures are taken to protect the surface from oxidation. Further, given the propensity of MoS2 to undergo oxidation in aqueous solutions, caution should be used when describing it as a true catalyst for reduction reactions (e.g., H2 evolution), unless proven otherwise.
The Revival of Economic Nationalism and the Global Trading System

The election of Donald J. Trump to the US Presidency coincided with the US adoption of an “America First” policy in trade. This policy reflects an underlying theory of economic nationalism that is fundamentally at odds with the current approach of the multilateral trading system established by the GATT/WTO. The current multilateral system is based on a “positive sum game” theory, i.e. the view that cooperative trade concessions can increase the volume of trade for all nations involved and result in reciprocal and mutual benefits. A large body of theoretical and empirical work, discussed and analyzed in this Article, supports the conclusion that the GATT/WTO system has historically achieved significantly increased trade volumes on both a multilateral and national scale since its creation at the end of the Second World War. By contrast, President Trump’s economic nationalism holds that trade is a “zero sum game” in which a gain in trade by one nation must be accompanied by a corresponding trade loss by another nation. Under the view of the current Administration, the US has often been the loser in the global trade deals of the GATT/WTO. The current Administration now seeks to dictate the terms of any future trade agreements so that the US wins at the expense of its trading partners, if necessary, in a zero sum game. The economic nationalism espoused by the current Administration, if unconstrained, could result in the dismantling of the current multilateral trading system leading to long-term negative, if not catastrophic, consequences for the world economy.
Risk Factors for Mid-Flexion Instability After Total Knee Arthroplasty: A Systematic Review.

Abstract Background Mid-flexion instability after total knee arthroplasty (TKA) is a clinical entity that is not well studied and one that has been associated with patient dissatisfaction and inferior outcomes. We sought to provide a comprehensive review of risk factors associated with mid-flexion instability. Methods A comprehensive literature search of PUBMED, EMBASE, Google Scholar, and Cochrane Library was performed using keywords “mid flexion,” “instability,” and “knee arthroplasty” in all possible combinations. All studies published from 2010 to 2020 in English were considered for inclusion. Research design, question studied, and outcomes were recorded for each study. Quantitative and qualitative analysis was performed. Results Eighteen articles meeting inclusion criteria were identified and reviewed. There were 5 computational studies, 5 cadaveric studies, and 8 clinical studies. There were 14 different risk factors investigated in relation to mid-flexion instability after TKA: 6 implant-related, 6 technique-related, and 2 patient-related factors. Of these risk factors, 5 had contradictory results published to date, resulting in an inconclusive association with mid-flexion instability. The results of this review suggest that the effects of joint line elevation and radius-of-curvature of the femoral component on mid-flexion instability are inconclusive while articular surface conformity and preoperative joint laxity may play a bigger role than previously thought. Conclusion Mid-flexion instability after TKA is a clinical entity distinct from other established forms of instability. There are patient-related, implant-related, and technique-related factors associated with mid-flexion instability. The majority of the evidence on this topic is derived from computational and cadaveric studies, underscoring the need for further clinical studies.
Description of Lepthyphantes rossitsae sp. n. from Turkey (Arachnida: Araneae: Linyphiidae)

A new species of Lepthyphantes (L. rossitsae sp. n.) was discovered while studying spider material collected from caves near Konya, Turkey. The species is described and illustrated and its relationship to the closely related L. leprosus (Ohlert, 1865) are discussed.
Ventriculoatrial shunts as an alternate therapy in patients with normal pressure hydrocephalus refractory to ventriculoperitoneal shunts: A Case series

Abstract Introduction Normal Pressure Hydrocephalus (NPH) is a prevalent neuropsychiatric disorder characterized by Hakim’s triad: Dementia, gait disturbance, and urinary incontinence in the setting of ventriculomegaly. Ventriculoperitoneal (VP) shunting is largely considered the definitive therapy for NPH. A significant limitation with VP shunts is their rate of failure, which is especially evident in the setting of increased intra-abdominal pressure (IAP). Methods We retrospectively analyzed the successful placement of ventriculoatrial (VA) shunts in two patients with NPH and increased IAP secondary to high BMI. We assessed outcomes based on improvements in fluency and mentation, patient-reported decreases in urinary frequency, and Tinetti-test assessments for gait. Results Both patients presented with short term memory loss, urinary incontinence, and shuffling gaits. Lumbar punctures performed in the hospital improved their symptoms, and VP shunts were placed with no improvement in gait or cognition. As both patients had high BMIs, we felt the shunts were not performing optimally due to high intraabdominal pressures and converted the VP shunts to VA shunts. This intervention finally provided long-lasting symptom relief at six- and ten-month follow-up, respectively. Conclusions The diversion of fluid performed by shunt therapy for NPH is dependent on a distal pressure lower than the patient’s intraventricular pressure. Overweight and obese patients may have elevated IAP of great clinical significance for VP shunt placement, and this variable merits consideration when neurosurgeons select which distal cavity is most appropriate for their NPH patients.
Cuticular features as indicators of environmental pollution

Several leaf cuticular features such as stomatal frequency, stomatal size, trichome length, type, and frequency, and subsidiary cell complex respond to environmental pollution in different ways and hence can be used as indicators of environmental pollution in an area. Several modifications in cuticular features under polluted environments seem to indicate ecotypic or survival significance for the plant species under investigation.
Rhesus macaque MHC class I molecules present HLA-B-like peptides.

SIV-infected Indian rhesus macaques ( Macaca mulatta ) are an important animal model for humans infected with HIV. Understanding macaque ( M. mulatta class I (Mamu)) MHC class I-peptide binding facilitates the comparison of SIV- and HIV-specific cellular immune responses. In this study, we characterized the endogenous peptide-binding properties of three Mamu-A (A*02, A*08, A*11) and three Mamu-B (B*01, B*03, B*12) class I molecules. Motif comparisons revealed that five of the six macaque class I molecules (A*02, A*08, A*11, B*01, and B*03) have peptide-binding motifs similar to those of human class I molecules. Of the 65 macaque endogenous peptide ligands that we sequenced by tandem mass spectroscopy, 5 were previously eluted from HLA class I molecules. Nonamers predominated among the individual ligands, and both the motifs and the individual ligands indicated P2, P9, and various ancillary anchors. Interestingly, peptide binding of the Mamu-A and Mamu-B molecules exhibited cross-species peptide-presentation overlap primarily with HLA-B molecules. Indeed, all of the macaque class I molecules appeared HLA-B-like in peptide presentation. Remarkably, the overlap in macaque- and HLA-peptide presentation occurred despite divergent class I peptide-binding grooves. Macaque and human class I differing by up to 42 aa (13–23%) within the α-1 and α-2 domains, including substantial divergence within specificity pockets A-F, bound the same endogenous peptide. Therefore, endogenous peptide characterization indicates that macaque class I molecules may be the functional equivalents of HLA-B molecules.
Understanding Cytokinesis Failure

Cytokinesis is the final step in cell division. The process begins during chromosome segregation, when the ingressing cleavage furrow begins to partition the cytoplasm between the nascent daughter cells. The process is not completed until much later, however, when the final cytoplasmic bridge connecting the two daughter cells is severed. Cytokinesis is a highly ordered process, requiring an intricate interplay between cytoskeletal, chromosomal and cell cycle regulatory pathways. A surprisingly broad range of additional cellular processes are also important for cytokinesis, including protein and membrane trafficking, lipid metabolism, protein synthesis and signaling pathways. As a highly regulated, complex process, it is not surprising that cytokinesis can sometimes fail. Cytokinesis failure leads to both centrosome amplification and production of tetraploid cells, which may set the stage for the development of tumor cells. However, tetraploid cells are abundant components of some normal tissues including liver and heart, indicating that cytokinesis is physiologically regulated. In this chapter, we summarize our current understanding of the mechanisms of cytokinesis, emphasizing steps in the pathway that may be regulated or prone to failure. Our discussion emphasizes findings in vertebrate cells although we have attempted to highlight important contributions from other model systems.
The Morality of Money: U.S. Attitudes Towards Wealth and the Income Tax

This Article explores the way in which American views regarding the morality of money affect tax debates and legislation. Part I traces and summarizes the roots of society's contradictory attitudes toward money and wealth which celebrate the accumulation of wealth on the one hand and the more egalitarian distributions on the other. Part II examines how these attitudes have played themselves out during the past century in the income tax laws and the accompanying debates. It focuses on three time periods during which radical changes occurred in the income tax and contrasts between attitudes toward wealth were glaring due to the predominance of the capitalist mode: (1) the establishment of the income tax, 1894-1913; (2) the 1920's; and (3) the modem era, the late 1970's to the present. Part III provides a short conclusion which summarizes some of the ways in which the contradictory attitudes toward wealth and the attendant rhetoric have shaped the income tax laws.The consistency of the income tax rhetoric illustrates the deep and abiding nature of the conflicting feelings of fear and admiration of wealth. Americans seek and admire earned wealth, yet fear its very power; they encourage saving as virtuous, yet worry about the ultimate consequences of great accumulations of wealth. While some people characterize these contradictions as two opposing traditions, this Article holds that the two are, in fact, intertwined into one broad tradition which I label moral economic individualism. In some historical periods, one facet dominates; in some people, one facet or the other is dominant. Yet, the recessive facet is ever-present, modifying the dominant one. The contradictory attitudes are reflected in the income tax. They help explain why the tax is an amalgam of consumption and income provisions and why it has failed to produce either dramatic progression or real redistribution of wealth.
Heterochromatin and Eurochromatin—Organization, Packaging, and Gene Regulation

The genomes of eukaryotes are packaged in chromatin, a complex of DNA with histones in a nucleosomal array, and folded further through interactions with other proteins into higher order domains. The different levels of packaging help define whether genes are available for expression, as in euchromatin, or generally silenced, as in heterochromatin. The condensed heterochromatin domains are characterized by a group of features, including low gene density, high levels of repetitious sequences, location at the nuclear periphery, late replication, and little recombination during meiosis, apparently reflecting a particular pattern of posttranslational modifications of the histones, association of heterochromatin-specific proteins, and regular spacing of nucleosomes. Keywords: DNA Modification; Epigenetics; Heterochromatin; Heterochromatin Protein 1 (HP1); Histones; Nucleosomes; Posttranslational Modification of Proteins; Repetitive DNA; Transposable Elements
3-13C-methionine-labelled E. coli alkaline phosphatase

3-13C-methionine has been biosynthetically incorporated into E. coli alkaline phosphatase using strain CW3747 which is auxotrophic for Met. 13C NMR of the dimeric native enzyme labelled at the eight methionine residues of the primary structure shows a dispersion of resonance signals permitting resolution of at least five methionine environments, none of which coincide with the chemical shift position of free methionine. At acid pH, 13C signal intensity is shifted to a chemical shift consistent with solvent exposure. However, three discrete resonances are observed, suggesting a retention of defined structure. The labelled protein thus can serve as a probe of conformational alterations of the enzyme.
Studies of novel cyclitols. A synthesis of 3′O,4′O-dimethylfuniculosin ☆

Abstract A synthesis of funiculosin dimethyl ether (2) is described. Methodologies for an asymmetric conjugate addition to establish the 1,3-anti dimethyl array, stereocontrolled formation of the Z,E-bis-allylic C-11 alcohol, and interception of a reactive pyridinone methide are examined.
Impact of weak excitatory synapses on chaotic transients in a diffusively coupled Morris-Lecar neuronal network

Spatiotemporal chaos collapses to either a rest state or a propagating pulse solution in a ring network of diffusively coupled, excitable Morris-Lecar neurons. Weak excitatory synapses can increase the Lyapunov exponent, expedite the collapse, and promote the collapse to the rest state rather than the pulse state. A single traveling pulse solution may no longer be asymptotic for certain combinations of network topology and (weak) coupling strengths, and initiate spatiotemporal chaos. Multiple pulses can cause chaos initiation due to diffusive and synaptic pulse-pulse interaction. In the presence of chaos initiation, intermittent spatiotemporal chaos exists until typically a collapse to the rest state.
High Resolution Comparative Genomic Hybridization (CGH) Indicates That Genomic Profiles Are Very Heterogeneous for HER2 and TOP2A in FISH-Amplified Human Breast Cancer Specimens.

Background: Clinical studies relating TOP2A and HER2 status by FISH and response to specific drug therapies, including anthracyclines, have yielded inconsistent results. The discordance across studies appears to reflect, in part, the well-documented limitations of FISH testing, including the use of large FISH probes to evaluate the relatively small genes of interest. However, it is also likely that the dichotomization of gene status into “amplified” or “non-amplified” categories inadequately describes complex changes across the gene areas of interest. Identification and delineation of specific amplification-deletion patterns in this region may be of significant clinical interest and could provide deeper insight into mechanisms of drug resistance. Consequently, we selected a subset of HER2 and TOP2A amplified specimens (by FISH) from an ongoing study of CGH, and examined individual amplification-deletion patterns by CGH. Methods: 471 consecutive, archived, formalin-fixed paraffin-embedded, >1cm, HER2 2+ and 3+ by immunohistochemistry primary breast cancer specimens diagnosed between January 2000 and 2006 were selected. HER2 status was evaluated by FISH at MSKCC and CGH at Cold Spring Harbor Laboratory (CSHL) for all 471 specimens in a double-blinded experiment and clinical correlates evaluated. TOP2A status was also evaluated by FISH at MSKCC and CGH at CSHL in the subset of 64 HER2 2+ by IHC, HER2 FISH-positive specimens. Individual genome profiles by CGH were examined for 20 HER2 and TOP2A FISH co-amplified specimens. Results: 45 specimens had results available for analysis, 20 of which were amplified for both HER2 and TOP2A by FISH. By CGH: 6/20 (30%) were not amplified for HER2 or TOP2A; 4/20 (20%) had homogeneous amplification of HER2 and TOP2A; 8/20 (40%) had HER2 > TOP2A amplification; and 2/20 (10%) had TOP2A > HER2 amplification. Individual genome profiles around HER and TOP2A were examined by CGH. Marked heterogeneity was observed across specimens. Conclusions: CGH at the genome level suggests that current dichotomization strategies for classifying HER2 and TOP2A status appear to incompletely describe and represent the heterogeneity of genomic lability in these regions. The dichotomization of gene amplification results by FISH may contribute to the discordance demonstrated in reported some clinical studies. Studies exploring clinical correlates are underway. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3165.
Batch emulsion copolymerization of 50/50 vinyl acetate/ n‐butyl acrylate using poly(vinyl alcohol) emulsifier

In the batch emulsion copolymerization of 50/50 vinyl acetate/n-butyl acrylate mixture, no emulsifier or sodium lauryl sulfate emulsifier gave a n-butyl acrylate-rich copolymer until the n-butyl acrylate became depleted, and a vinyl acetate-rich copolymer and poly(vinyl acetate) thereafter, as expected from the disparate copolymerization reactivity ratios (r1 0.05; r2 5). In contrast, poly(vinyl alcohol) emulsifier gave an initial polymerization of vinyl acetate at a rate equal to or greater than that of the n-butyl acrylate up to 7–37% conversion; then, the n-butyl acrylate polymerized preferentially until it became depleted, followed by the remaining vinyl acetate, to give a vinyl acetate-rich copolymer and poly(vinyl acetate), as expected from the copolymerization reactivity ratios. The mechanism proposed for this process comprised the grafting of vinyl acetate on the poly(vinyl alcohol) in solution to give a water-insoluble graft copolymer, which precipitated and served as the locus for nucleation of poly(n-butyl acrylate)-rich particles. Fully hydrolyzed poly(vinyl alcohol) required a higher degree of grafting to give a water-insoluble graft copolymer than partially hydrolyzed poly(vinyl alcohol).
Effects of cold acclimation, hibernation and temperature on succinoxidase activity of heart homogenates from hamster, rat and squirrel monkey

Abstract 1. 1. The effects of temperature on heart homogenate succinoxidase activity have been studied in preparations from hamsters (Mesocricetus auratus), rats and squirrel monkeys (Saimiri sciureus). 2. 2. Squirrel monkey heart homogenates show a greater temperature sensitivity between 5 and 15°C than preparations from rodents. This suggests that these animals may prove to be more susceptible to severe hypothermia than either rats or hamster. Q 10 values between 15 and 37°C were similar in all three species. 3. 3. No depression of succinoxidase activity was seen in heart homogenates from hibernating compared with active hamsters. 4. 4. There were no significant differences in the temperature sensitivities of homogenates from hamsters and rats which might account for the greater tolerance of the hibernator heart to hypothermia.
Extraction of diethylhexylphthalate from total nutrient solution-containing polyvinyl chloride bags.

Total nutrient solution (TNS) is a new method for delivering total parenteral nutrition (TPN) by admixing dextrose, amino acids, and lipids in a single container. Recommendations are to use nonpolyvinyl chloride (PVC) containers for admixture of these solutions. PVC is a hard, brittle, and inflexible substance, and plasticizers, predominantly diethylhexylphthalate (DEHP), are added to impart flexibility. DEHP is a lipid soluble suspected carcinogen, hepatotoxin, and teratogen which has been shown to leach from PVC products containing lipophilic admixtures. The purpose of this study was to quantitate the amount of DEHP which leaches from PVC bags containing TNS.Six study groups, which contained three formulas stored at 25°C ± 2°C and 4°C ± 1°C, were assayed for DEHP at time 0, 12, 24, 48 and 72 hr, 1 wk, and 3 wk using high-performance liquid chromatography. The control group contained an amino acid source, a carbohydrate source, and standard electrolytes, and the other groups contained a 10% lipid source ...
Comparative Requirements of Linoleic Acid for Male and Female Chicks

Abstract THE levels of 5,8,11-eicosatrienoate (triene) and arachidonate (tetraene) in animal tissues have been shown to be related to dietary linoleate (18:2). Holman (1960) first demonstrated that the ratio of triene:tetraene in the tissues of the rat is indicative of the essential fatty acid status of the animal. This criterion has been used by others to determine the 18:2 requirement of chicks. Hill (1966) estimated the 18:2 requirement of the male chick to be 2% of total dietary calories by plotting the ratio of triene:tetraene versus the percentage of total calories supplied by 18:2. Bieri and Prival (1966) determined the 18:2 requirement of male chicks on the basis of growth and the triene:tetraene ratio of fatty acids in liver and erythrocytes and found the requirement to be between 1–1.8%. Later, Hopkins and Nesheim (1967) estimated the requirement of straight-run chicks to be approximately 2.2 to 3.8% of total calories. Since…
Patient‐Family‐Nurse Intensive Care Unit Experience ‐ A Roy Adaptation Model‐Based Qualitative Study

This qualitative phenomenological study examined the experiences of patients, their family members, and the nurses in the intensive care unit during critical illness. Five participants from each category participated in two interviews over a period of five months. Content analysis of the interview transcripts revealed five integrating common themes, each reflecting concepts from the Roy Adaptation Model (RAM). The ICU experience among all participants is interdependence. Adaptation in the ICU integrated family as a unit, physical care/comfort, physiological care and psychosocial support, resulting in transformation.
The Context of Ethical Problems in Medical Volunteer Work

Ethical problems are common in clinical medicine, so medical volunteers who practice clinical medicine in developing countries should expect to encounter them just as they would in their practice in the developed world. However, as this article argues, medical volunteers in developing countries should not expect to encounter the same ethical problems as those that dominate Western biomedicine or to address ethical problems in the same way as they do in their practice in developed countries. For example, poor health and advanced disease increase the risks and decrease the potential benefits of some interventions. Consequently, when medical volunteers intervene too readily, without considering the nutritional and general health status of patients, the results can be devastating. Medical volunteers cannot assume that the outcomes of interventions in developing countries will be comparable to the outcomes of the same interventions in developed countries. Rather, they must realistically consider the complex medical conditions of patients when determining whether or not to intervene. Similarly, medical volunteers may face the question of whether to provide a pharmaceutical or perform an intervention that is below the acceptable standard of care versus the alternative of doing nothing. This article critically explores the contextual features of medical volunteer work in developing countries that differentiate it from medical practice in developed countries, arguing that this context contributes to the creation of unique ethical problems and affects the way in which these problems should be analyzed and resolved.
Methods for inferring paleohabitats from discrete traits of the bovid postcranial skeleton

Abstract Various “ecomorphological” methods exist for using the functional morphology of bovid postcranial remains to reconstruct paleohabitats. Most such methods use measurements, but both Gentry [The Bovidae (Mammalia) of the Fort Ternan fossil fauna, in: L.S.B. Leakey, R.J.G. Savage (Eds.), Fossil Vertebrates of Africa, vol. 2, Academic Press, London, 1970, pp. 243–323] and Kohler [Skeleton and Habitat of Recent and Fossil Ruminants, Munchner Geowissenschaftliche Abdhandlungen 25 (1993) 1–88] have identified numerous discrete (non-metric) traits of the bovid postcranial skeleton that are said to be indicative of habitat preference. However, these traits have not been systematically tested on a modern bovid sample. We report here such a test. Eighty-six non-metric characters were evaluated using a sample of modern African bovids ( n = 197). Of the 86 characters, 48 were either insufficiently defined or exhibited too much intra-individual variation to be potentially indicative of habitat. Two characters were invariant in the sample. Of the remaining 36 characters, 11 were sufficiently correlated with habitat preference (Cramer's V > 0.5) to be of some potential use in reconstructing paleohabitats. These characters are primarily concentrated on the phalanges, and provide a means by which fragmentary phalanges can be used for habitat reconstruction, albeit at a broad level of resolution (open or closed habitat). The estimated accuracy of these methods is greater than 80%. Their use on fragmentary remains may lessen the bias introduced by basing habitat reconstructions on more complete fossils.
Laser Desorption Time-of-Flight Mass Spectrometry of Inorganic Nanoclusters: An Experiment for Physical Chemistry or Advanced Instrumentation Laboratories

New experiments for the undergraduate laboratory are described using laser desorption time-of-flight (TOF) mass spectrometry to produce and analyze a variety of inorganic nanoclusters. Laser vaporization of solid powder samples of sulfur, phosphorus, and bismuth all produce gas-phase cluster ions with unusual mass spectral patterns. This experiment provides an introduction to TOF mass spectrometry and ultrasmall nanoclusters, as well as hands-on experience in vacuum systems, lasers, oscilloscopes, and pulsed electronics. New concepts in chemical bonding for inorganic materials are explored.
Transforming faith in corporate capitalism through business ethics

Although faith is typically associated with religious experience, it is the contention of this paper that people are faith-guided creatures, and the practice of business is itself based on an experience of faith – not a religious faith, but an existential faith, by which we mean a deeply held belief embedded in one’s understanding of what the fundamental nature of reality is and how one ought to act. In our contemporary industrialized society, the dominant system for organizing work is corporate capitalism, which, as we see it, is neither inherently good nor bad. Corporate capitalism, however, has been infused with a normative faith that gives primacy to profit maximization and personal enrichment, and in so doing opens the door to corrupting forces that debase business. In this paper, we will suggest that business ethics can infuse corporate capitalism with a transforming faith that affirms a personal dignity through service to the greater good.
THE SOLUBLE SPECIFIC SUBSTANCE OF PNEUMOCOCCUS : THIRD PAPER.

1. Refinements in the methods for the isolation of the soluble specific substances of Types II and III pneumococcus are described. These improvements have resulted in the isolation of the end-products in a form free from nitrogen and of enhanced activity with immune serum. 2. The soluble specific substance of Type I pneumococcus is described and shown to differ sharply from the corresponding substances of the other two types, each of which, in turn, differs from the other. 3. Progress is reported on the identification of the sugar units from which the polysaccharides are built up. 4. The evidence so far accumulated is believed to favor strongly the view that the polysaccharides isolated are the actual specific substances of Pneumococcus.
Maternal Mental Health and Pediatric Health Care Use Among a National Sample of Medicaid- and SCHIP-Insured Children

While the literature has shown that health care use is associated with mental health status, little is known about the relationship between a mother's mental health status and her children's health care use. This study examined the association of maternal mental health status and pediatric health care for their children in a nationally representative sample of 17,830 women parenting children ages 0-17 insured through Medicaid or a State Children's Health Insurance Program (SCHIP). Mothers with a mental health problem were significantly more likely to be poorer, single parents, with lower levels of education, fewer parenting supports, and greater difficulty coping with parenting than mothers without a mental health problem; however, they reported comparable receipt of pediatric health care for their children, indicating their resilience as caretakers. The findings also suggest that all Medicaid- or SCHIP-eligible families could benefit from targeted engagement strategies linking them with consistent and appropriate sources of pediatric health care.
Paleoenvironmental interpretations of oxygen isotope ratios in oolitic ironstones

Abstract Material balance calculations were applied to the results of selective dissolution, X-ray diffraction, chemical and isotopic analyses to determine the δ18O values of oolitic goethites (α-FeOOH). Well-preserved ooids from low paleolatitude (≤35°) ironstones of Late Ordovician, Early Jurassic, Early Middle Jurassic, and Late Middle Jurassic ages have goethite δ18O values that range from −2.3 to +1.7 ‰. Late Cretaceous goethite from a high paleolatitude (55°N) deposit has a δ18O value of −5.2 ‰. The measured δ18O values of the ancient goethites are significantly different from the δ18O values expected for goethites which would form in the modern environments at each site. In contrast, there is good agreement between measured and hypothetical δ18O values of goethites from a variety of young deposits. This suggests that the ancient goethites have not isotopically reequilibrated with modern waters and supports an assumption that these oolitic goethites have preserved δ18O values reflecting ancient environments of formation. All of the oolitic goethite δ18O values analyzed for this work are consistent with formation in continental settings. A comparison with the isotopic systematics of modern, globally distributed meteoric waters indicates that the four oolitic goethites from low paleolatitudes probably formed in environments with average rainfall that exceeded 1200 mm/yr. The high paleolatitude oolitic ironstone formed near the western margin of the North American Late Cretaceous seaway. Few modern sites from the global IAEA network appear to be reasonable thermal and isotopic analogs for the Late Cretaceous environment of this deposit. Therefore, it is possible that the ancient seaway modified the Late Cretaceous hydrologic cycle to produce a local meteoric water with a combination of thermal and isotopic signatures that is not common at present. δ18O values of mineral pairs from the Late Ordovician and Early Jurassic deposits yield calculated paleotemperatures of about 23°C and 32°C (±4°C), respectively. Both epochs appear to have been characterized by atmospheric PCO2 values that were as much as 16–18 times higher than modern. The association of a comparatively low tropical temperature (and an ice sheet at high paleolatitude) with high atmospheric PCO2 might have been a result of lower solar luminosity in the Late Ordovician.
Selective bowel decontamination results in gram-positive translocation.

Abstract Colonization by enteric gram-negative bacteria with subsequent translocation is believed to be a major mechanism for infection in the critically ill patient. Selective bowel decontamination (SBD) has been used to control gram-negative infections by eliminating these potentially pathogenic bacteria while preserving anaerobic and other less pathogenic organisms. Infection with gram-positive organisms and anaerobes in two multivisceral transplant patients during SBD led us to investigate the effect of SBD on gut colonization and translocation. Methods: Twenty-four rats received enteral polymixin E, tobramycin, amphotericin B, and parenteral cefotaxime for 7 days (PTA + CEF); 23 received parenteral cefotaxime alone (CEF), 19 received the enteral antibiotics alone (PTA), 21 controls received no antibiotics. Cecal homogenates, mesenteric lymph node (MLN), liver, and spleen were cultured. Results: Only 8% of the PTA + CEF group had gram-negative bacteria in cecal culture vs 52% CEF, 84% PTA, and 100% in controls. Log Enterococcal colony counts were higher in the PTA + CEF group (8.0 + 0.9) vs controls (5.4 + 0.4) P
Laser micromachining in the microelectronics industry

The use of lasers in microelectronics production for trimming, link cutting, ablating, drilling and general “micromachining” continues to grow. Several new technologies, such as alternative wavelength processing and shaped, uniform laser spots have produced better processing quality, higher reliability, and greater yields. This paper will review the latest technologies of laser micro-machining in microelectronics. Laser drilling for printed circuit board will be dressed in another paper.
Closed-Loop Rehabilitation of Age-Related Cognitive Disorders

Cognitive deficits are common in older adults, as a result of both the natural aging process and neurodegenerative disease. Although medical advancements have successfully prolonged the human lifespan, the challenge of remediating cognitive aging remains. The authors discuss the current state of cognitive therapeutic interventions and then present the need for development and validation of more powerful neurocognitive therapeutics. They propose that the next generation of interventions be implemented as closed-loop systems that target specific neural processing deficits, incorporate quantitative feedback to the individual and clinician, and are personalized to the individual's neurocognitive capacities using real-time performance-adaptive algorithms. This approach should be multimodal and seamlessly integrate other treatment approaches, including neurofeedback and transcranial electrical stimulation. This novel approach will involve the generation of software that engages the individual in an immersive and enjoyable game-based interface, integrated with advanced biosensing hardware, to maximally harness plasticity and assure adherence. Introducing such next-generation closed-loop neurocognitive therapeutics into the mainstream of our mental health care system will require the combined efforts of clinicians, neuroscientists, bioengineers, software game developers, and industry and policy makers working together to meet the challenges and opportunities of translational neuroscience in the 21st century.
A Conceptual Proof of Cramer's Rule

Proof. The classical way to solve a linear equation system is by performing row operations: (i) add one row to another row, (ii) multiply a row with a nonzero scalar and (iii) exchange two rows. We show that the quotient in equation (1) will not change under row operations. Under the first row operation, the values of the two determinants det(Ai) and det(A) will not change, since determinants are invariant under this row operation. Under the second row operation both determinants will gain the same factor, which cancels in the quotient. Finally, under the third row operation both determinants will switch sign, which again cancels in the quotient. Since every invertible matrix A can be row reduced to the identity matrix, it is now enough to prove Cramer's rule for the identity matrix. However, this is a straightforward task. i
The influence of short-term adventure-based experiences on levels of resilience

This exploratory study investigated the impact of participation in a three-week adventure education (AE) expedition upon levels of resilience of university students. Resilience is considered to be a dynamic process of positive adaptation to significant threat or adversity and may be an important variable to study as college students often live stressful lives involving academic workloads, relationship building and self-identity that often require the development of coping skills and resilience. Little research, however, has been conducted on the ability to enhance levels of resilience through AE activities within a college or university setting. The specific research questions studied included: (1) Do resilience scores change as a result of a short-term AE experience, and (2) What specific experiences did participants report that were related to the concept of resilience? Using a mixed method, with quantitative responses from the treatment group and the comparison group, paired sample t-tests resulted in ...
Immunoselection of simian virus 40 large T antigen messenger rnas from transformed cells.

Abstract The messenger RNAs (m-RNAs) coding for the simian virus 40 (SV40) large tumor antigen were substantially purified by immunoprecipitation of polysome fractions from SV40-transformed cells. The level of SV40 T antigen m-RNA in the transformed cell used in this study was estimated at 0.05% of the total population of polyadenylated m-RNAs and a several-hundred-fold purification of this m-RNA was achieved by employing antibodies to SV40 large T antigen purified by either of two methods. The procedures described in this communication should be particularly useful for the immunoselection and purification of low-abundance m-RNAs or when the antigen is not available in large quantities.
Lymphocyte Interaction: A Potential Histocompatibility Test in vitro

Lymphocytes from two unrelated individuals, cultured together in the same tube, undergo morphological transformation to large cells and divide. Both of these parameters may be estimated quantitatively. There is a correlation between the degree of this response and the degree of cross-reactivity of grafts from the two individuals placed on a third unrelated recipient.
Comparison Of Imaging Characteristic Of Digital Subtraction Angiography Utilizing Geometrical Magnification And Electro-Optical Magnification

The resolution characteristics of a digital subtraction angiographic (DSA) system have been evaluated under two different magnification techniques, namely; the geometrical magnification, and the electro-optical magnification. It has been found that the DSA system resolution is less dependent on the focal spot size (or, modulation transfer function, MTF) than that of routine radiographic angiographic studies. The evaluation results have been utilized to re-establish the DSA examination procedure.
Raman scattering by localized modes

Abstract Raman scattering from the T2 fundamental and T2 and A1 second harmonics of the localized mode for H- and D- in CaF2, SrF2 and BaF2 are reported, and are in substantial agreement with theoretical explanations of the i.r. spectra for the same systems.
Altered Expression of the PMAIP1 Gene: A Major Player in the Evolution of Gastrointestinal and Systemic Malignancies

To the Editor I read with interest the recent article by Ishida et al. [1] in a recent issue of this journal. The PMAIP1 gene is a tumor suppressor gene that is an important mediator of p53-related apoptosis. Recent studies show that altered expression of the PMAIP1 gene is involved in the development of a number of systemic malignancies besides pancreatic cancer. For instance, Kim et al. [2] in a recent study have identified the PMAIP1 gene as one of the genes in homozygously deleted regions in colorectal cancers. Similarly, altered expression of the PMAIP1 gene is involved in the evolution of breast cancers [3]. Altered expression of the PMAIP1 gene has also been demonstrated in endometrial cancer cell lines [4]. Similarly altered expression of the PMAIP1 gene has been implicated in the transformation of follicular lymphomas to diffuse large cell lymphomas [5]. Various external influences may alter the expression of the PMAIP1 gene. For instance, it has been demonstrated that bortezomib upregulates the PMAIP1 gene in retinoblastoma cells [6], while Ackerstaff et al. [7] have shown that indomethacin has a similar impact on the PMAIP1 gene in breast cancer cells. Similarly, human chorionic gonadotropin has been shown to upregulate the PMAIP1 gene in endometriotic cells [8]. On the other hand, Ploner et al. [9] have shown that glucocorticoids cause repression of the PMAIP1 gene in patients with acute lymphoblastic leukemia. Clearly, the upor downregulation of the PMAIP1 gene plays a major role in the evolution or repression of numerous systemic malignancies. The study of Ishida et al. [1] adds to the vast array of malignancies in which the PMAIP1 gene plays a major role. Hopefully, the near future will see the development of safe and effective agents by means of which oncologists will be able to regulate the expression of the PMAIP1 gene.