cssi/SciSciGPT-SciSciNet huggingface dataset:
Biogeography on the eve of the twenty-first century: Towards an epistemology of biogeography

Vuilleumier, F. 1999. Biogeography on the eve of the twenty-first century: Towards an epistemology of biogeography. In: Adams, N.J. & Slotow, R.H. (eds) Proc. 22 Int. Ornithol. Congr., Durban. Ostrich 70 (1): 89–103. 'No one knows what…changes in our image of science the future may bring. The best one can do under the circumstances is to try to present an outline of the kind of science that prevails in our time, at the end of the twentieth century' (Mayr 1997: 26). To reconstruct the spatio-temporal development of life on earth biogeographers have traditionally used several units of analysis and various kinds of data. The species has long been a fundamental unit, and a map of a species' distribution a basic datum. Some recent workers reject the biological species concept and advocate a phylogenetic one instead. Just as the definition of species may be changing, new technology and new mapping techniques are enlarging the concept of map. Through area cladograms, cladistics has modified the way taxonomic and...
A discrete damage mechanics model for high cycle fatigue in polycrystalline materials subject to rolling contact

Fatigue behavior of polycrystalline materials is significantly influenced by their microstructural topology. The microstructural heterogeneity is one of the primary reasons for dispersion in high cycle fatigue lives of such materials. In this work, a damage mechanics based fatigue model that incorporates gradual material degradation under cyclic loading is presented in conjunction with a discrete material representation that takes the material microstructural topology into account. Microstructures are generated stochastically through the process of Voronoi tessellation. Micro-crack initiation, coalescence and propagation stages are modeled using damaged zones in a unified framework. The model is applied to study high cycle fatigue in rolling contacts. The effect of material topological disorder and inhomogeneity on fatigue life dispersion is studied. Fatigue damage is found to originate sub-surface and propagate towards the surface. Sub-surface damage patterns from the model are consistent with experimental observations. Propagation life is found to constitute a significant fraction of total life. Lives are found to follow a 3-parameter Weibull distribution. The relative proportion of lives spent in the initiation and propagation stages are in good quantitative agreement with experiments.
138 Relationship between coronary calcification and endothelium dependent coronary vaso-reactivity in asymptomatic diabetic patients without overt coronary artery disease

Methods We studied 23 (mean age 63 ± 10, 19 M, 4 F) patients with type II DM, without history, symptom or ECG evidence of CAD. The subjects underwent 1-day rest-stress adenosine nuclear stress test, assessment of coronary calcification by EBCT and absolute measurement of myocardial blood flow at rest (MBF-R), and following cold-water hand immersion for 1 minute (MBF-C). All imaging studies were performed within 24 hours. Flow measurements by CMRI was performed using saturation recovery TurboFLASH imaging sequence: TR/TE/TI/FA = 2.9 ms/1.3 ms/ 90 ms/6°, data matrix 128 × 70, and usual voxel spatial resolution 3.5 × 1.9 × 8 mm3. Contrast dose was 0.05 mmol/kg (Omniscan, Amersham). All scans were processed in a blinded fashion. Using Medis software (Leiden University, the Netherlands), basal, mid-cavity and apical slices were divided into 6 equal transmural sectors. After correction for coil sensitivity variations, model independent deconvolution of myocardial signal intensity curves in the sectors, with blood pool signal intensity curves was performed. MBF-R and MBF-C in mls/g/min were determined. Endothelium dependent perfusion reserve (MPR) in these sectors were calculated as the ratios of MBF-C to MBF-R in each sector. The sectors wre subsequently grouped based on standard coronary vascular distribution.
Diamonds: time capsules from the Siberian Mantle

Diamonds are thought to be “time capsules” from the Earth's mantle. However, by themselves, consisting of nearly pure carbon, diamonds provide little geochemical information about their conditions of formation and the nature of their mantle hosts. This obstacle to studying the origin of diamonds and their hosts can be overcome by using two main approaches that focus on studying: (1) the rocks that contain diamonds, i.e., diamondiferous xenoliths; and (2) mineral inclusions within the diamonds, the time capsule's little treasures, if you will. Diamondiferous xenoliths, their diamonds, and mineral inclusions within the diamonds are the subject of this review, focusing on studies of samples from the Yakutian kimberlites in the Siberian Platform. Studies of diamondiferous eclogite xenoliths significantly enhance our understanding of the complex petrogenesis of this important group of rocks and their diamonds. Such studies involve various geochemical and petrological investigations of these eclogites, including major and trace-element, radiogenic as well as stable isotopic analyses of whole rocks and minerals. The results from these studies have clearly established that the Group A–C eclogites originate from subduction of ancient oceanic crust. This theory is probably applicable worldwide. Within the last several years, our research group at Tennessee has undertaken the systematic dissection (pull apart) of diamondiferous eclogites from Siberia, consisting of the following steps: (1) high-resolution computed X-ray tomography of the xenoliths to produce 3D images that relate the minerals of the xenoliths to their diamonds; (2) detailed dissection of the entire xenolith to reveal the diamonds inside, followed by characterization of the setting of the diamonds within their enclosing minerals; and (3) extraction of diamonds from the xenolith for further investigation of the diamonds and their inclusions. In this last step, it is important that the nature and relative positions of the diamond inclusions are carefully noted in order to maximize the number of inclusions that can be exposed simultaneously on one polished surface. In this modus operandi, cathodoluminescence imaging, plus FTIR/N aggregation and C/N isotopic analyses are performed on polished diamond surfaces to reveal their internal growth zones and the spatial relationship of the mineral inclusions to these zones. Knowledge gained by such detailed, albeit work-intensive, studies continues to add immensely to the constantly evolving models of the origin of diamonds and their host rocks in the Earth's mantle, as well as to lithospheric stability models in cratonic areas. Multiple lines of evidence indicate the ultimate crustal origin for the majority of mantle eclogites. Similar pieces of evidence, particularly from δ13C in P-type diamonds and δ18O in peridotitic garnets lead to the suggestion that at least some of the mantle peridotites, including diamondiferous ones, as well as inclusions in P-type diamonds, may have had a crustal protolith as well.
Differential regulation of rat liver selenoprotein mRNAs in selenium deficiency.

Summary Selenium deficiency causes a fall in the concentrations of selenoproteins but selenoprotein P and type I iodothyronine 5′-deiodinase (5′-deiodinase) are more resistant to this effect than is glutathione peroxidase. To investigate the differential regulation of these selenoproteins, a selenium-deficient diet was fed to weanling rats for 14.5 weeks and their hepatic mRNAs were measured by Northern analysis. Levels of all 3 mRNAs fell progressively with time. Selenoprotein P and 5′-deiodinase mRNAs remained higher at all time points relative to control than glutathione peroxidase mRNA. mRNA decreases were mirrored by decreases in glutathione peroxidase activity and selenoprotein P concentration. However, the decreases in the protein levels were greater than the decreases in their mRNAs, suggesting that synthesis of both proteins was limited to a similar extent at the translational level by the availability of selenium. In addition to this apparently unregulated translational effect, these results point to a pretranslational regulation, affecting mRNA levels, which could account for the differential effect of selenium deficiency on glutathione peroxidase and the other selenoproteins. This regulation might serve to direct selenium to selenoprotein P and 5′-deiodinase when limited amounts of the element are available.
Still Delirious after All These Years

With the emergence of intensive care in the 1950s and 1960s, delirium became more prominent. Doctors quickly set out to understand and prevent it, but delirium results from so many sources that decisive understanding remains elusive.
Anticoagulant action of protamine sulphate.

SummaryProtamine sulphate in low concentrations affects both rate and yield of blood thromboplastin but has no effect on formed thromboplastin. Relatively higher concentrations inhibit a reaction between blood thromboplastin, prothrombin and calcium.
Theory of atomic chemisorption on simple metals

We use the atom-jellium model of chemisorption to study the properties of an atom bonded to the surface of a simple metal. Beyond the jellium simulation of the metal substrate and the Kohn-Sham local-density description of exchange and correlation, we make no significant approximations: our solutions are parameter free, wave mechanical, and fully self-consistent. We solve this model for a set of adatoms exhibiting a variety of chemical behaviors. Properties studied include the electron-density distribution, the state density, the dipole moment, and the heat of adsorption. We discuss also the reintroduction of the discrete lattice structure of the substrate using perturbation theory.
Clinical annotation of tobacco use in patient charts at Indian Health Service clinics and hospitals

Few clinicians would doubt the importance of obtaining smoking histories from their patients. Nevertheless a clinicians' practices of documenting tobacco use in medical records varies substantially among individual providers and between different health care systems. To investigate the chart documentation of patient smoking among Indian Health Service clinicians, we reviewed 545 randomly selected patient records from 22 different Indian Health Service affiliated clinics. We focused on differences in charting of tobacco use by type of clinic and by geographic area within the Indian Health Service. Documentation varied by area, ranging from no documentation in the Albuquerque, Navajo, and Phoenix areas to 51% in the Oklahoma area. We conclude that clinicians practices of documentation of tobacco use vary widely and recommend that this practice be more widely encouraged at all affiliated Indian Health Service clinics.
Photodynamic therapy for esophageal carcinoma

Esophageal carcinoma continues to have a poor prognosis with limited treatment options. Potential surgical curative treatment exists only for early stage cancers, with palliative treatment used for the most advanced cancers. Photodynamic therapy (PDT) is a treatment modality for both early and advanced cancers of the esophagus that has shown encouraging results. This article reviews the background, biology, and mechanism of photodynamic therapy in cancer treatment. In particular, the indiciations and contraindications to PDT with regard to esophageal carcinoma are discussed, as well as the need for proper patient selection and pretreatment evaluation. Specific detail will be provided in discussing the technique of administering photodynamic therapy for the treatment of esophageal cancers. The administration of the light photosensitizer, selection of the appropriate light dosimetry, proper endoscopic delivery of the light treatment, and recommended follow-up for both early and late stage cancers after completion of PDT are discussed. Finally, complications that can occur with the use of this relatively new treatment and how to avoid and manage these complications are reviewed.
An Image Drift Compensation System for a Solar Pointed Space Telescope

An Image Drift Compensation System has been designed for a solar pointed space borne telescope and has performed successfully on two sounding rocket flights, yielding new scientific results. The system employs limb-sensing photodiodes at the telescope focal plane and provides drift compensation to better than 0.1 arc sec. A variation of the system will be used on the Shuttle/Spacelab 2 flight of the High Resolution Telescope and Spectrograph (HRTS) Instrument.
Alcohol synthesis with ZNCR catalysts in a slurry reactor

A laboratory stirred autoclave reactor has been developed to operate at temperatures up to 375°C and pressures of at least 170 atma. The performance of a commercial “high pressure” methanol synthesis catalyst, the so-called “zinc chromite” catalyst, has been characterized over a range of temperature from 300 to 375°C, pressures from 68 to 174 atma, H2CO ratios from 0.5 to 2.0 and space velocities from 1500 to 10000 sL/kg(catalyst)-hr. Towards the lower end of the temperature range, methanol was the only significant product. At the highest temperatures, the methanol synthesis reaction was close to equilibrium. There were significant quantities of methane, dimethyl ether and olefins in the product at these temperatures. Formation of higher alcohols was insignificant, although small amounts of isobutanol were formed at the highest temperatures and pressures, with 10 mole percent CO2 in the feed gas.
Constructing neighborhoods from the bottom up: The case for resident-generated GIS

As in other areas of planning practice, the use of GIS in neighborhood planning has assumed a technical top-down approach. Given the fact that GIS are essentially about providing and analyzing spatial data, it is difficult to envision how their use in local communities could be construed otherwise. In this paper I make a case for the need to channel intellectual energy into developing an approach and methodology for resident-generated GIS. Specifically I argue that there is a need to exploit GIS in the investigation of residents' perceptions of local neighborhood environments. I explore this approach in five sections. First, I present a definition of resident-generated GIS and position it within the larger debate on public participation GIS. Second, I offer a review of the current use of GIS in local neighborhood communities. This consists of an empirical assessment of neighborhood GIS as well as a critique of community GIS from the perspective of scholars in planning and geography. Third, I review the th...
Multi-level submap based SLAM using nested dissection

We propose a novel batch algorithm for SLAM problems that distributes the workload in a hierarchical way. We show that the original SLAM graph can be recursively partitioned into multiple-level submaps using the nested dissection algorithm, which leads to the cluster tree, a powerful graph representation. By employing the nested dissection algorithm, our algorithm greatly minimizes the dependencies between two subtrees, and the optimization of the original SLAM graph can be done using a bottom-up inference along the corresponding cluster tree. To speed up the computation, we also introduce a base node for each submap and use it to represent the rigid transformation of the submap in the global coordinate frame. As a result, the optimization moves the base nodes rather than the actual submap variables. We demonstrate that our algorithm is not only exact but also much faster than alternative approaches in both simulations and real-world experiments.
Comparison of arithmetic and geometric means as measures of a central tendency in cattle nematode populations.

Abstract Efficacy calculations in anthelmintic studies require estimates of the central tendency for the nematode populations. Confusion exists among practitioners regarding which measures of central tendency are most appropriate; although the arithmetic mean is frequently used, there are theoretical reasons for preferring the geometric mean. To investigate this controversy, arithmetic and geometric means were compared for their suitability for use in measuring efficacy. Arithmetic and geometric means were compared as measures of central tendency for skewed distributions. The following criteria were developed to facilitate the comparison: (1) probability around the parameter, (2) influence of extreme values, and (3) proximity to the median. Under log-normality, theoretical results demonstrated the superiority of the geometric mean. Modified-bootstrap simulations using empirical data from cattle were used to confirm theoretical expectations. Simulations on log-normal data supported the geometric mean as the better indicator of the central tendency. Additionally, for data not confirmed as log-normal, the superiority of geometric means was demonstrated. In a comparison of precision, it was shown that mean squared error was always smaller for sample geometric means than for arithmetic means when n ≥2. Simulation results added support to that conclusion.
Bioavailability of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to the prairie vole (Microtus ochrogaster).

Estimating risk to wildlife requires that measures of exposure be equivalent to that of the laboratory studies from which toxic responses were observed. Exposure measures are often based on modeled estimates of uptake through the food web. These modeled estimates use largely untested assumptions that can lead to inaccurate, uncertain, and unreliable estimates of exposure. Recently, concerns have been raised over the potential bioavailability and biotransfer of munitions or energetics materials such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). RDX is more recalcitrant in the soil, may remain as the parent compound for extended periods of time, and is rapidly taken up by the roots of higher plants and partitioned predominantly into the above ground, herbivore-accessible tissues. This study assessed plant incorporated [14C]-RDX and plant derived [14C]-RDX-metabolites ingestion by a representative hindgut herbivore, the prairie vole (Microtus ochrogaster). The animals were fed the labeled chow (≤10 g/ day max) for five or seven days followed by a six or four day chase period with the control chow prior to final weighing and sacrifice. Animal excreta including feces, urine, and respired CO2 were collected and measured. Greater than 95% of all label presented to the voles was recovered in the summed excreta. Seventy-four percent ofmore » the label in the total excreta was found in the fecal non-absorbed bulk. This means that greater than 20% of the presented 14C-RDX and plant-derived 14C-RDX-metabolites were absorbed by the animal’s digestive tracts over the time course of the experiment and modified prior to release. These materials were either metabolized to 14CO2 (8 to 10% of the total label) or removed as nitrogenous waste through the kidneys (10 to 14%). The feeding regimes were followed by a rapid, 2 to 3 day, clearing of label from the bulk feces with the cessation of exposure. Both 14C-urine and 14CO2 excretion continued after the feces cleared indicating ongoing metabolism of the absorbed labeled material. Approximately 4% of the label presented in the chow over the exposure periods was retained within the animal’s tissues at time of sacrifice. Activity was found in the lung, heart, brain, spleen, testes, skeletal muscle, bone, and pancreatic tissues while the testes contained the highest tissue specific activity. The liver contained the highest activity of all the internal organs. All of these tissues which contain these [14C]-RDX derived materials are readily available to subsequent predators this may indicate a potential for this material to transfer to a higher trophic level.« less
SPATIAL CHOICES AND EXCESS COMMUTING: A CASE STUDY OF BANK TELLERS IN BOGOTA, COLOMBIA

Abstract This study uses disaggregate data from Bogota, Colombia to examine the presumption that individuals engaging in excess commuting have satisfactorily traded commuting for other location benefits. By estimating involuntary and voluntary excess commuting, the study illustrates that deviations from the minimum commute implied by the urban spatial structure are expected due to temporal and structural constraints, even when the journey-to-work is a household’s only locational concern. Therefore, the usefulness of excess commuting estimates for informing policy choices hinging on the connection between transportation and land use would increase if the voluntary and involuntary components of excess commuting were incorporated explicitly into such calculations. Results suggest that future excess commuting research should devote additional attention to contextual factors constraining individual spatial choices.
Perceptual Accuracy in the Balance: The Weight of the Evidence and the Evidence of Weight

In two studies, we investigated whether individuals were accurate in perceiving weight-related attitudes of their romantic partner. We also investigated whether accuracy was moderated by whether the partner was currently attempting to lose weight, relationship commitment level, amount of discussion about weight and importance of weight. Each individual answered questions assessing their own weight concerns and perceptions, and similar questions assessing their partner's weight concerns and perceptions. We found evidence that perceptual inaccuracy of weight-related attitudes was greatest when one's partner was attempting to lose weight in relationships of shorter duration, lower commitment, or in which they rarely discussed weight. Self-ratings and partner's perceptions were positively correlated.
Looking to the future: a new decade of pulmonary arterial hypertension therapy

Pulmonary arterial hypertension (PAH) is a severe and debilitating disease characterised by vascular proliferation and remodelling of the small pulmonary arteries, leading to a progressive increase in pulmonary vascular resistance, increased afterload on the right ventricle and, ultimately, right heart failure. Although there is no “cure” for PAH, the availability of targeted therapies over the past decade has led to major advances in the management of PAH, reflected in improvements in survival in the modern treatment era. However, despite this, disease progression is inevitable in the majority of patients with PAH and overall the long-term prognosis, although improved, remains poor. There is a clear and urgent need for new therapeutic options, either through the development of improved drugs that act on targets established by existing PAH-specific therapies, or of agents targeting novel pathogenic pathways not addressed by currently available therapies. A number of such new agents that have shown promise in experimental models and preliminary human studies are discussed in this article.
The vimE Gene Downstream of vimA Is Independently Expressed and Is Involved in Modulating Proteolytic Activity in Porphyromonas gingivalis W83

Regulation/activation of the Porphyromonas gingivalis gingipains is poorly understood. A unique 1.3-kb open reading frame downstream of the bcp-recA-vimA transcriptional unit was cloned, insertionally inactivated with the ermF-ermAM antibiotic resistance cassette, and used to create a defective mutant by allelic exchange. In contrast to the wild-type W83 strain, the growth rate of the mutant strain (designated FLL93) was reduced, and when plated on Brucella blood agar it was nonpigmented and nonhemolytic. Arginine- and lysine-specific gingipain activities were reduced by approximately 90 and 85%, respectively, relative to activities of the parent strain. These activities were unaffected by the culture's growth phase, in contrast to the vimA-defective mutant P. gingivalis FLL92, which has increased proteolytic activity in stationary phase. Expression of the rgpA, rgpB, and kgp gingipain genes was unaltered in P. gingivalis FLL93 compared to that of the wild-type strain. Further, in extracellular protein fractions a 64-kDa band was identified that was immunoreactive with the RgpB-specific proenzyme antibodies. Active-site labeling with dansyl-glutamyl-glycyl-arginyl chloromethyl ketone or immunoblot analysis showed no detectable protein band representing the gingipain catalytic domain. In vitro protease activity could be slightly induced by a urea denaturation-renaturation cycle in an extracellular protein fraction, in contrast to the vimA-defective mutant P. gingivalis FLL92. Expression of flanking genes, including recA, vimA, and Pg0792, was unaltered by the mutation. Taken together, these results suggest that the vimA downstream gene, designated vimE (for virulence-modulating gene E), is involved in the regulation of protease activity in P. gingivalis.
Understanding safety and performance in the cardiac operating room: from ‘sharp end’ to ‘blunt end’

Successful surgery requires a patient with an accurate diagnosis, a treatment plan with an acceptable chance of success, a skilled surgeon and supporting team, a range of equipment, drugs and disposable items to support complex surgical tasks, a follow-up care team to ensure appropriate postoperative recovery and discharge, and an organisation that supports the people and helps to coordinate the delivery of all aspects of care. The tragic consequences that can ensue from failures across this broad range of system components came to light in the case of paediatric cardiac surgery some 15 years ago. Incidents in Winnipeg, Canada,1 and Bristol, UK,2 led to inquiries into surgical deaths that were among the first to highlight the complex range of systemic influences on surgical performance. These thorough analyses revealed a huge range of ‘blunt end’ system problems: surgical volumes, leadership and organisational issues, dysfunctional communication between teams and departments, and the basic predisposition to error imposed by the complex amalgam of team, task, process and technical ability within the surgery itself. Emerging partly from those events was perhaps the seminal observational multidisciplinary study in surgical care conducted by Carthey and de Leval et al .3 They demonstrated that even successful operations were often fraught with large numbers of potential problems that arose as a result of systems issues. More importantly for outcomes-based research, they found that enough of these minor problems in one operation could contribute to increased morbidity and mortality.4 Furthermore, the actions of the team in recovering from these problems could make the difference between a good and a poor outcome.5 This study was therefore critical in making direct inferential links between surgical outcomes, human factors and systems issues. Subsequent research developed these observational techniques and a suggested model for understanding error causation in surgery. …
Contribution of pollen to atmospheric ice nuclei concentrations

Abstract. Recent studies have suggested that the ice-nucleating ability of some types of pollen is derived from non-proteinaceous macromolecules. These macromolecules may become dispersed by the rupturing of the pollen grain during wetting and drying cycles in the atmosphere. If true, this mechanism might prove to be a significant source of ice nuclei (IN) concentrations when pollen is present. Here we test this hypothesis by measuring ambient IN concentrations from the beginning to the end of the 2013 pollen season in Raleigh, North Carolina, USA. Air samples were collected using a swirling aerosol collector twice per week and the solutions were analysed for ice nuclei activity using a droplet freezing assay. Rainwater samples were collected at times when pollen grain number concentrations were near their maximum value and analysed with the drop-freezing assay to compare the potentially enhanced IN concentrations measured near the ground with IN concentrations found aloft. Ambient ice nuclei spectra, defined as the number of ice nuclei per volume of air as a function of temperature, are inferred from the aerosol collector solutions. No general trend was observed between ambient pollen grain counts and observed IN concentrations, suggesting that ice nuclei multiplication via pollen grain rupturing and subsequent release of macromolecules was not prevalent for the pollen types and meteorological conditions typically encountered in the southeastern US. A serendipitously sampled collection after a downpour provided evidence for a rain-induced IN burst with an observed IN concentration of approximately 30 per litre, a 30-fold increase over background concentrations at −20 °C. The onset temperature of freezing for these particles was approximately −12 °C, suggesting that the ice-nucleating particles were biological in origin.
Mechanism of measles virus failure to activate NF-κB in neuronal cells

Lack of IFN-β and MHC class I expression in measles virus (MV) infected neurons could impair the host antiviral defense mechanism and result in virus escape from recognition by cytotoxic T-cells. Induction of IFN-β and MHC class I gene expression requires NF-κB activation which depends on degradation of IκBα, an inhibitory protein of NF-κB. In earlier studies we demonstrated that in contrast to glial cells, MV was unable to induce IκBα degradation in neuronal cells. It is unclear whether this failure is due to the presence of a neuron-specific IκBα isoform or a defect in the MV signaling cascade that leads to IκBα phosphorylation and degradation. In this study, an IκBα-wild type (WT) expression vector was transfected into neuronal and glial cells and subsequently exposed to MV. In contrast to glial cells, IκBα-WT was degraded in neuronal cells in response to TNFα but not MV. The findings eliminate the existence of an IκBα isoform in neuronal cells that is resistant to phosphorylation by MV. Blocking de novo protein synthesis with cyclohexamide had no effect on neuronal IκBα, indicating that lack of degradation rather than increased synthesis is responsible for IκBα accumulation in MV-stimulated neuronal cells. To determine if malfunction in the MV receptor CD46 is responsible for failure of IκBα phosphorylation and degradation, neuronal cells were transfected with a wild type CD46 (CD46-WT) expression vector. MV stimulation of CD46-WT transfected cells failed to induce IκBα degradation. Collectively these findings indicate that failure of MV to phosphorylate neuronal IκBα is not due to a presence of an IκBα isoform or malfunction of the MV receptor, and is more likely to be due to a defect in the signaling pathway that normally leads to IκBα phosphorylation and degradation.
Incident investigation of mono-nitro toluene still explosion

Abstract At one of the nitro-toluene facilities, an o-nitro toluene still was in standby mode. During the standby mode feed to the still had been stopped, the column was not de-inventoried, steam flow to the reboiler was not shut off and the condenser was on total reflux. After 22 days of standby mode, steam was shut off for 5 days for annual plant maintenance. Eight days after the re-start of steam, the still exploded, hurling debris as far as one mile. The internal packing was expelled from the column and landed on the ground burning. The incident was investigated to establish the contributing factors leading to explosion. Accelerating Rate Calorimetery was extensively used to determine the onset temperature for exothermic activity in the presence/absence of a number of materials to establish the underlying cause of the accident. It was found that foulant collected in the column over a period of years accelerated the ’runaway reaction’.
Mass measurement accuracy comparisons between a double‐focusing magnetic sector and a time‐of‐flight mass analyzer

We report a direct comparison of the mass measurement accuracies (MMAs) obtained on different mass spectrometry instrument types; a magnetic sector as the 'gold standard' and an electrospray ionization time-of-flight (ESI-TOF) instrument. Sixty samples, obtained from the Department of Chemistry at North Carolina State University, were analyzed on each instrument. Data are presented and compared between the different instruments. The average absolute MMAs achieved for the magnetic sector and Agilent ESI-TOF mass spectrometers were 3.0 and 1.1 ppm, respectively.
A Conceptual Framework for Teaching Statistics from a Distance

This article discusses important considerations for teachers who teach or may be thinking about teaching statistics online or in a hybrid/blended format. Suggestions from previous research and practical teaching experiences are examined. Moreover, the latest recommendations from the literature are considered in the context of teaching from a distance, which includes the 2014 curriculum guidelines published by the American Statistical Association (ASA Curriculum Undergraduate Guidelines Workgroup, 2014) and the Guidelines for Assessment and Instruction in Statistics Education (GAISE) College Report (2005; 2012). The paper concludes with suggestions about essential next steps to further advance our understanding of teaching and learning in this environment.
Dynamically Downscaled Projections of Lake-Effect Snow in the Great Lakes Basin*,+

AbstractProjected changes in lake-effect snowfall by the mid- and late twenty-first century are explored for the Laurentian Great Lakes basin. Simulations from two state-of-the-art global climate models within phase 5 of the Coupled Model Intercomparison Project (CMIP5) are dynamically downscaled according to the representative concentration pathway 8.5 (RCP8.5). The downscaling is performed using the Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model version 4 (RegCM4) with 25-km grid spacing, interactively coupled to a one-dimensional lake model. Both downscaled models produce atmospheric warming and increased cold-season precipitation. The Great Lakes’ ice cover is projected to dramatically decline and, by the end of the century, become confined to the northern shallow lakeshores during mid-to-late winter. Projected reductions in ice cover and greater dynamically induced wind fetch lead to enhanced lake evaporation and resulting total lake-effect precipitation, altho...
Pediatric Suprastomal Granuloma: Management and Treatment

Abstract Objective Suprastomal granulomas (SSG) are a common complication of pediatric tracheotomy. Occasionally excision is indicated for obstructive granulomas. We report on our experience on the management of SSG requiring excision. Study design and setting A retrospective chart review of 68 patients who underwent SSG excision at a tertiary referral pediatric hospital between July 1997 and November 2002. The medical charts were reviewed for excision techniques and outcomes. Results A total of 106 excisions of SSG were performed on 68 patients. Of the patients, 25 (36.8%) required multiple excisions. Removal techniques included sphenoid punch (34.9%), optical forceps (34.0%), open excision (22.6%), electrocautery (4.7%), and hook and eversion (3.8%). Conclusion The majority of SSG do not require removal. If excision is indicated, we recommend using optical forceps for soft and friable lesions and the sphenoid punch for fibrous and firm granulomas. For granulomas that have a broad base, are very large, or where endoscopic instrumentation is not possible, we recommend open excision.
An interferometric method for dynamic extinction ratio measurement

We introduce a novel interferometric method for dynamic extinction ratio measurement of temporally demultiplexed pulses by using a high extinction modulator. The resulting extinction ratio is 44 dB. Our method has a dynamic range of ~60 dB.
Privacy Preserving Delegated Access Control in Public Clouds

Current approaches to enforce fine-grained access control on confidential data hosted in the cloud are based on fine-grained encryption of the data. Under such approaches, data owners are in charge of encrypting the data before uploading them on the cloud and re-encrypting the data whenever user credentials change. Data owners thus incur high communication and computation costs. A better approach should delegate the enforcement of fine-grained access control to the cloud, so to minimize the overhead at the data owners, while assuring data confidentiality from the cloud. We propose an approach, based on two layers of encryption, that addresses such requirement. Under our approach, the data owner performs a coarse-grained encryption, whereas the cloud performs a fine-grained encryption on top of the owner encrypted data. A challenging issue is how to decompose access control policies (ACPs) such that the two layer encryption can be performed. We show that this problem is NP-complete and propose novel optimization algorithms. We utilize an efficient group key management scheme that supports expressive ACPs. Our system assures the confidentiality of the data and preserves the privacy of users from the cloud while delegating most of the access control enforcement to the cloud.
A realistic spline-based dynamic heart phantom

We develop a realistic computerized heart phantom for use in medical imaging research. This phantom is a hybrid of realistic patient-based phantoms and flexible geometry-based phantoms. The surfaces of heart structures are defined using non-uniform rational B-splines (NURBS), as used in 3D computer graphics. The NURBS primitives define continuous surfaces allowing the phantom to be defined at any resolution. Also, by fitting NURBS to patient data, the phantom is more realistic than those based on solid geometry. An important innovation is the extension of NURBS to the fourth dimension, time, to model heart motion. Points on the surfaces of heart structures were selected from a gated MRI study of a normal patient. Polygon surfaces were fit to the points for each time frame, and smoothed. 3D NURBS surfaces were fit to the smooth polygon surfaces and then a 4D NURBS surface was fit through these surfaces. Each of the principal 4D surfaces (atria, ventricles, inner and outer walls) contains approximately 200 control points, We conclude that 4D NURBS are an efficient and flexible way to describe the heart and other anatomical objects for a realistic phantom.
Gabapentin in PTSD: A retrospective, clinical series of adjunctive therapy

Posttraumatic stress disorder (PTSD) symptoms may improve significantly with antidepressant medications, however some phenomena often remain refractory to the most commonly used treatments. Frequently, sleep disturbances, such as insomnia and nightmares, are symptoms of PTSD that are refractory to antidepressant treatment. Gabapentin, a novel anticonvulsant agent, has been of interest as a potential anxiolytic agent, but has not been evaluated in PTSD. We reviewed records of 30 consecutive patients who had been diagnosed with PTSD according to structured interviews and had received gabapentin as an adjunctive medication. For each patient, the target symptoms that led to the initiation of gabapentin treatment were identified. Using the most recent clinical data available, the change in target symptom severity following treatment was rated as unimproved, mildly improved, moderately improved, or markedly improved. The gabapentin was often first prescribed to facilitate sleep. The majority (77%) of patients showed moderate or greater improvement in duration of sleep, and most noted a decrease in the frequency of nightmares. The dose range was 300-3600 mg/day. Sedation and mild dizziness were the most commonly reported side effects. This retrospective study suggests that gabapentin may improve in particular sleep difficulties and also other symptoms associated with chronic PTSD. Prospective, controlled studies are needed to further investigate the effects of gabapentin on insomnia, nightmares, and other core PTSD symptoms.
Footprints in the sand: independent reduction of subdigital lamellae in the Namib–Kalahari burrowing geckos

Many desert organisms exhibit convergence, and certain physical factors such as windblown sands have generated remarkably similar ecomorphs across divergent lineages. The burrowing geckos Colopus, Chondrodactylus and Palmatogecko occupy dune ecosystems in the Namib and Kalahari deserts of southwest Africa. Considered closely related, they share several putative synapomorphies, including reduced subdigital pads (toe pads) and spinose digital scales. Though recognized as part of Africa’s ecologically diverse Pachydactylus Group, the burrowing geckos’ precise phylogenetic affinities remain elusive. Convergent pedal modification provides a tenable alternative explaining the geckos’ derived terrestriality and adaptation to Namib and Kalahari sands. We generated a molecular phylogeny for the Pachydactylus Group to examine evolutionary relationships among the burrowing geckos and infer historical patterns of pedal character change. Bayesian and parsimony analyses revealed all three burrowing genera to be deeply nested within Pachydactylus, each genus belonging to a separate clade. Strong support for these distinct clades indicates ecomorphological adaptations for burrowing have evolved independently three times in the southern Pachydactylus Group. We argue that the physical properties of Namib and Kalahari sands played a principal role in selecting for pedal similarity.
Indirect estimation of soil hydraulic properties to predict soybean yield using GLYCIM

GLYCIM, a mechanistic model of soybean (Glycine Max L.) growth and development, requires soil hydraulic parameters as input. These data are usually not readily available. The objective of this study alas to compare yields calculated with measured hydraulic properties to those calculated with hydraulic properties estimated from soil texture and bulk density. We reviewed estimation methods and chose two methods to estimate a soil moisture release function and two methods to obtain saturated hydraulic conductivity. Both methods use soil texture and bulk densit), as predictors. Soil water retention predicted bJ3 these methods correlated ,t,ell with measured soil water retention whereas the estimation of saturated hydraulic conductivity was poor. Soybean yields were simulated using GLYCIM with and without irrigation ,for seven locations in Mississippi. USA, using seven years of weather records. Simulated Isields lz’ere aJTected more by the method of estimating the moisture release curve than b>, the method of estimating saturated hJ,draulic conductivity. The average simulated yields from estimated properties tz‘ere higher than those from measured properties because estimated bllater retention provided more availuble water. Correlation betbtleen yields simulated using measured and estimated hydraulic properties was higher under non-irrigated conditions than ti,ith irrigation. Averaging I’ields over years lcith diflerent lveather conditions greatl_v improved the correlations. Published b?, Elserier Science Ltd
Crystal structure of phosphoglucose isomerase from Trypanosoma brucei complexed with glucose-6-phosphate at 1.6 A resolution

Enzymes of glycolysis in Trypanosoma brucei have been identified as potential drug targets for African sleeping sickness because glycolysis is the only source of ATP for the bloodstream form of this parasite. Several inhibitors were previously reported to bind preferentially to trypanosomal phosphoglucose isomerase (PGI, the second enzyme in glycolysis) than to mammalian PGIs, which suggests that PGI might make a good target for species-specific drug design. Herein, we report recombinant expression, purification, crystallization and X-ray crystal structure determination of T. brucei PGI. One structure solved at 1.6 A resolution contains a substrate, D-glucose-6-phosphate, in an extended conformation in the active site. A second structure solved at 1.9 A resolution contains a citrate molecule in the active site. The structures are compared with the crystal structures of PGI from humans and from Leishmania mexicana. The availability of recombinant tPGI and its first high-resolution crystal structures are initial steps in considering this enzyme as a potential drug target.
Effect of implantation accuracy on ankle contact mechanics with a metallic focal resurfacing implant.

Background: Talar osteochondral defects can lead to joint degeneration. Focal resurfacing with a metallic implant has shown promise in other joints. We studied the effect of implantation accuracy on ankle contact mechanics after focal resurfacing of a defect in the talar dome. Methods: Static loading of seven cadaver ankles was performed before and after creation of a 15-mm-diameter osteochondral defect on the talar dome, and joint contact stresses were measured. The defect was then resurfaced with a metallic implant, with use of a custom implant-bone interface fixture that allowed fine control (in 0.25-mm steps) of implantation height. Stress measurements were repeated at heights of –0.5 to +0.5 mm relative to an as-implanted reference. Finite element analysis was used to determine the effect of implant height, post axis rotation, and valgus/varus tilt over a motion duty cycle. Results: With the untreated defect, there was a 20% reduction in contact area and a 40% increase in peak contact stress, as well as a shift in the location of the most highly loaded region, as compared with the values in the intact condition. Resurfacing led to recovery of 90% of the contact area that had been measured in the intact specimen, but the peak contact stresses remained elevated. With the implant 0.25 mm proud, peak contact stress was 220% of that in the intact specimen. The results of the finite element analyses agreed closely with those of the experiments and additionally showed substantial variations in defect influences on contact stresses across the motion arc. Talar internal/external rotations also differed for the unfilled defect. Focal implant resurfacing substantially restored kinematics but did not restore the stresses to the levels in the intact specimens. Conclusions: Focal resurfacing with a metallic implant appears to have the potential to restore normal joint mechanics in ankles with a large talar osteochondral defect. However, contact stresses were found to be highly sensitive to implant positioning. Clinical Relevance: Resurfacing a talar osteochondral defect with an implant that restores the joint contour, that provides immediate stability, and that reproduces normal joint mechanics, without requiring biological potential, offers advantages over existing resurfacing techniques; however, restoration of normal joint mechanics is highly dependent on precise surgical implantation.
Teaching of an undergraduate control course with laboratory: needs, vision and issues

Various issues related to teaching and integration of a senior undergraduate intelligent system course and its laboratory are discussed. This course aims at providing students a comprehensive view of recent development in intelligent control design techniques using Neural Networks (NN) and Fuzzy Logic (FL) with lab experiments. Emphasis is on controller design for industrial applications.
Ten polymorphic microsatellite markers for pronghorn (Antilocapra americana)

We screened enriched genomic libraries of the North American endemic pronghorn, Antilocapra americana, using di-, tri- and tetranucleotide repeat probes. We characterized ten polymorphic microsatellite loci for 45 individuals from the National Bison Range (NBR), Montana, and 47 individuals from Yellowstone National Park (YNP), Montana and Wyoming. The number of alleles per locus ranged from two to 12. Observed heterozygosity ranged from 0.33 to 0.94. No loci deviated from Hardy–Weinberg equilibrium (HWE) in the NBR population, but one locus deviated from HWE in the YNP population. Linkage disequilibrium was detected in one pair of loci in the NBR population and one pair in the YNP population following a Bonferroni correction. We tested all loci for cross-species amplification in the Mongolian gazelle (Procapra gutturosa). Four loci successfully amplified and three were polymorphic, suggesting that these primers may be of use in population genetics studies of Bovids as well as Antilocaprids.