cssi/SciSciGPT-SciSciNet huggingface dataset:
Compound Prioritization through Meta-Analysis Enhances the Discovery of Antimicrobial Hits against Bacterial Pathogens.

The development of informatic tools to improve the identification of novel antimicrobials would significantly reduce the cost and time of drug discovery. We previously screened several plant (Xanthomonas sp., Clavibacter sp., Acidovorax sp., and Erwinia sp.), animal (Avian pathogenic Escherichia coli and Mycoplasma sp.), and human (Salmonella sp. and Campylobacter sp.) pathogens against a pre-selected small molecule library (n = 4182 SM) to identify novel SM (hits) that completely inhibited the bacterial growth or attenuated at least 75% of the virulence (quorum sensing or biofilm). Our meta-analysis of the primary screens (n = 11) using the pre-selected library (approx. 10.2 ± 9.3% hit rate per screen) demonstrated that the antimicrobial activity and spectrum of activity, and type of inhibition (growth versus virulence inhibitors) correlated with several physico-chemical properties (PCP; e.g., molecular weight, molar refraction, Zagreb group indexes, Kiers shape, lipophilicity, and hydrogen bond donors and acceptors). Based on these correlations, we build an in silico model that accurately classified 80.8% of the hits (n = 1676/2073). Therefore, the pre-selected SM library of 4182 SM was narrowed down to 1676 active SM with predictable PCP. Further, 926 hits affected only one species and 1254 hits were active against specific type of pathogens; however, no correlation was detected between PCP and the type of pathogen (29%, 34%, and 46% were specific for animal, human foodborne and plant pathogens, respectively). In conclusion, our in silico model allowed rational identification of SM with potential antimicrobial activity against bacterial pathogens. Therefore, the model developed in this study may facilitate future drug discovery efforts by accelerating the identification of uncharacterized antimicrobial molecules and predict their spectrum of activity.
Molecular Biology of Atherothrombotic Brain Infarction and Its Role in Vascular Dementia

Dementia due to vascular disease results from ischemic infarctions affecting crucial areas of brain by virtue of their critical nature for memory, such as the hippocampus/dentate gyrus or dorsal medial nucleus of the thalamus; the aggregate mass of infarcts; and the bilateral involvement of cortical damage. However, the most important factor causing ischemic infarction is atherosclerotic vascular disease in both large and small arteries and arterioles. Since the best therapy for both strokes and vascular dementia is prevention, it follows that insights into the fundamental molecular biological mechanisms of atherosclerosis in patients with vascular dementia should provide clues for identifying genetic predisposition and planning rational therapeutic intervention. The hope and expectation is that the offending atherosclerotic changes can be prevented and reversed, thereby averting any ischemic brain injury and the potential for secondary dementia.
Celia Brickman: Aboriginal Populations in the Mind: Race and Primitivity in Psychoanalysis

Celia Brickman opens ‘‘Aboriginal Populations in the Mind’’ by posing the following question: ‘‘How does psychoanalysis configure racial difference, and what do we learn when we consider this questions from a postcolonial perspective?’’ (Brickman, 2003, p. 1). My own experience as a social work student, instructor and practitioner has been that many of us either never ask this question or respond to it with a definitive ‘‘poorly!’’ On the one hand, Freud and the entire psychoanalytic project is often dismissed as irrelevant at best and oppressive at worst with regard to its acknowledgement and treatment of the social fact of racial difference, leading some clinicians to abandon it in favor of social theories that address such issues. On the other hand, some clinicians whose practice is helped by Freud’s theory sometimes do not focus as much on the fact of racial difference, concentrating instead on the symbolic content of the intrapsychic life of their patients. At a recent lecture on analytic technique, a well-regarded and clearly competent psychoanalyst stated, ‘‘I am interested in the workings of the unconscious. Anything that takes place outside of that is none of my business.’’ As social workers, we have made it our business to be concerned about both the unconscious lives of our patients as well as the external worlds with which they contend. Brickman’s question regarding psychoanalysis’ configuring of racial differences, and the exploration of the answer that follows in this book, gives a glimmer of hope at a rapprochement between the two. The book is composed of five chapters that as a whole comprise a ‘‘sustained argument in which each chapter builds on the one(s) preceding it’’ (Brickman, 2003, p. 11). Approaching psychoanalysis as a ‘‘critical discourse (that is) eminently suited to analyze and deconstruct racist and colonialist thought’’ (Brickman, 2003, p. 8), the author describes the book as
The utilization of the rabbit alveolar macrophage and Chinese hamster ovary cell for evaluation of the toxicity of particulate materials: II. Particles from coal-related processes

Rabbit alveolar macrophage (RAM) and Chinese hamster ovary (CHO) cells were used in in vitro tests to evaluate the toxicity of particulate effluents from coal gasification, fluidized-bed combustion, and conventional coal combustion. Evaluation of the cytotoxicity of nine samples from coal energy-related processes showed that the sensitivity of the RAM assay was improved substantially when the test was conducted in serum-free media. A linear relationship was observed between percentage cell viability and ATP level in the particletreated cultures. In the RAM assay without serum the slope of the line was 1.0, which provided strong evidence that the mechanism of toxicity was similar in reducing cell viability and ATP. The cytotoxicity of the coal-related particles in the CHO clonal assay showed that the system was approximately equivalent to the RAM assay without serum. Conventional coal combustion fly ash (<3 μm) was the most toxic of the coal-related particles in the RAM and CHO system. Fluidized-bed combustion fly ash from a cyclone catch and fine (<3 μm) particles from the flue gas were also toxic in both cellular assays. Particles from the coal gasification process were the least cytotoxic in these studies.
Biochemical Consequences of Type 2 Adenovirus and Simian Virus 40 Double Infections of African Green Monkey Kidney Cells

African green monkey kidney (AGMK) cells were nonpermissive hosts for type 2 adenovirus although the restriction was not complete; when only 3 plaque-forming units/cell was employed as the inoculum, the viral yield was about 0.1% of the maximum virus produced when simian virus 40 (SV40) enhanced adenovirus multiplication. The viral yield of cells infected only with type 2 adenovirus increased as the multiplicity of infection was increased. Type 2 adenovirus could infect almost all AGMK cells in culture; adenovirus-specific early proteins and DNA were synthesized in most cells, but small amounts of late proteins were made in relatively few cells. Even when cells were infected with both SV40 and adenovirus, only about 50% were permissive for synthesis of adenovirus capsid proteins. Approximately the same quantity of adenovirus deoxyribonucleic acid (DNA) was synthesized in the restricted as in the SV40-enhanced infection. However, in cells infected with SV40 and type 2 adenovirus, replication of SV40 DNA was blocked, multiplication of SV40 was accordingly inhibited, and synthesis of host DNA was not stimulated. To enhance propagation of type 2 adenovirus, synthesis of an early SV40 protein was essential; 50 mug of cycloheximide per ml prevented the SV40-induced enhancement of adenovirus multiplication, whereas 5 x 10(-6)m 5-fluoro-2-deoxyuridine did not abrogate the enhancing phenomenon.
Neonatal Dermatophytosis: Report of a Case and Review of the Literature

Tinea capitis is a common fungal infection in children but rare among neonates. We present a case of a 3-week-old infant with multiple scalp lesions for 1 week. A diagnosis of tinea capitis due to Microsporum canis was made based on clinical morphology, Wood's lamp, and biopsy with a positive PAS stain. She was effectively treated with oral griseofulvin and ketoconazole shampoo.
ATP Synthase Complex: PROXIMITIES OF SUBUNITS IN BOVINE SUBMITOCHONDRIAL PARTICLES (∗)

The catalytic sector, F1, and the membrane sector, F0, of the mitochondrial ATP synthase complex are joined together by a 45-A-long stalk. Knowledge of the composition and structure of the stalk is crucial to investigating the mechanism of conformational energy transfer between F0 and F1. This paper reports on the near neighbor relationships of the stalk subunits with one another and with the subunits of F1 and F0, as revealed by cross-linking experiments. The preparations subjected to cross-linking were bovine heart submitochondrial particles (SMP) and F1-deficient SMP. The cross-linkers were three reagents of different chemical specificities and different lengths of cross-linking from zero to 10 A. Cross-linked products were identified after gel electrophoresis of the particles and immunoblotting with subunit-specific antibodies to the individual subunits alpha, beta, gamma, delta, OSCP, F6, A6L, a (subunit 6), b, c, and d. The results suggested that the two b subunits form the principal stem of the stalk to which OSCP, d, and F6 are bound independent of one another. Subunits b, OSCP, d, and F6 cross-linked to alpha and/or beta, but not to gamma or delta. The COOH-terminal half of A6L, which is extramembranous, cross-linked to d but not to any other stalk or F1 subunit. No cross-links of subunits a and c with any stalk or F1 subunits were detected. In F1-deficient SMP, cross-linked b+b and d+F6 dimers appeared, and the extent of cross-linking between b and OSCP diminished greatly. The addition of F1 to F1-deficient particles appeared to reverse these changes. Treatment of F1-deficient particles with trypsin rapidly hydrolyzed away OSCP and F6, fragmented b to membrane-bound 18-, 12-, and 8-9-kDa antigenic fragments, which cross-linked to d and/or with one another. Trypsin also removed the COOH-terminal part of A6L, but the remainder still cross-linked to subunit d. Models showing the near neighbor relationships of the stalk subunits with one another and with the alpha and beta subunits at a level near the proximal end (bottom) of F1 and at the membrane-matrix interface are presented.
Factors Secreted by Human Neuroblastoma Mediate Doxorubicin Resistance by Activating STAT3 and Inhibiting Apoptosis

The transcription factor Stat3 has been reported to play a key role in protecting cells against apoptosis by up-regulating expression of the anti-apoptotic gene Bcl-xL. This investigation analyzes the relationship between the development of resistance to doxorubicin-mediated apoptosis in neuroblastoma cells (SKN-SH) and activation of the Stat3 signaling pathway. A drug-resistant cell line (SKN-SH/Dox6) was generated by continuous exposure to incremental concentrations of doxorubicin. Specific antibodies were utilized for Western blots and confocal microscopy to determine the nuclear localization of activated Stat3. Doxorubicin-mediated DNA fragmentation was inhibited and caspase-3 activity decreased in SKN-SH/Dox6 cells. Up-regulation of Stat3 phosphorylation and Bcl-xL expression, increased nuclear translocation of phospho-Stat3, and binding to DNA occurred only in resistant SKN-SH/Dox6 cells. The expression of Bcl-xL was inhibited by AG490, an inhibitor of the JAK/Stat3 signaling pathway, suggesting that the regulation of Bcl-xL and Stat3 involved a common mechanism. Activation of Stat3 in SKN-SH/Dox6 cells was contingent upon stimulation evoked by ligands secreted by the drug-resistant cells. Evidence to support this hypothesis was provided by experiments in which doxorubicin-sensitive SKN-SH cells were preincubated with conditioned media obtained from doxorubicin-resistant SKN-SH/Dox6 cells. This treatment increased Stat3 activation. It also rendered SKN-SH cells resistant to doxorubicin as demonstrated by a sharp decrease in doxorubicin-induced DNA degradation and cytotoxic potency. These findings suggest that the resistance of SKN-SH/Dox6 cells to doxorubicin may be mediated by anti-apoptotic factor(s) that are synthesized and secreted by tumor cells in response to cytotoxic agents.
Sunspot Seismology: The Interaction of a Sunspot with Solar P-Modes

This article surveys developments in “sunspot seismology” from the decade following the original suggestion of Thomas et al (1982) that observations of solar acoustic oscillations in and about sunspots could be used to probe the internal structure of the sunspot with depth. Both the theoretical and observational components of sunspot seismology are considered at length, but considerably less is said about the presently ill-defined “inverse problem” for sunspot seismology. Much of our present understanding of the interaction of acoustic oscillations with magnetic flux tubes has been developed through careful consideration of idealized but instructive examples. A large part of this review is accordingly devoted to a discussion of these important sunspot seismology paradigms. Undoubtedly the highlight of the last ten years of research is the observational program carried out by Braun, Duvall and La Bonte (1987,1988,1990) demonstrating (i) that the interaction of p-modes with sunspots is sufficiently robust to be measured, and moreover, (ii) that sunspots appear to absorb up to 50% of the acoustic energy flux that is incident upon them.
Energy proportionality for disk storage using replication

Saving energy for storage is of major importance as storage devices (and cooling them off) may contribute over 25 percent of the total energy consumed in a datacenter. Recent work introduced the concept of energy proportionality and argued that it is a more relevant metric than just energy saving as it takes into account the tradeoff between energy consumption and performance. In this paper, we present a novel approach, called FREP (Fractional Replication for Energy Proportionality), for energy management in large datacenters. FREP includes a replication strategy and basic functions to enable flexible energy management. Specifically, our method provides performance guarantees by adaptively controlling the power states of a group of disks based on observed and predicted workloads. Our experiments, using a set of real and synthetic traces, show that FREP dramatically reduces energy requirements with a minimal response time penalty.
Soft tissue mechanics of the temporomandibular joint.

Direct measurement of temporomandibular joint (TMJ) tissue deformation requires animal experimentation. Most of the available data pertain to the mechanical strain on the bone surfaces around the join
Learning about other agents in a dynamic multiagent system

We analyze the problem of learning about other agents in a class of dynamic multiagent systems, where performance of the primary agent depends on behavior of the others. We consider an online version of the problem, where agents must learn models of the others in the course of continual interactions. Various levels of recursive models are implemented in a simulated double auction market. Our experiments show learning agents on average outperform non-learning agents who do not use information about others. Among learning agents, those with minimum recursion assumption generally perform better than the agents with more complicated, though often wrong assumptions.
Materials science: designer pores made easy.

Imagine being able to tweak the properties of a compound simply by replacing a molecular 'cartridge' with a different one. Just such a capability has been developed in a new class of porous crystalline materials.
A new notion of part structure for natural language

Abstract In this paper a new notion of part structure for the semantics of natural language is presented: a notion of part structure that is relative to a situation and unlike extensional mereological notions, crucially involves conditions of integrity. The notion is motivated by a variety of different constructions of natural language.
Extended dual affine planes

We study a class of diagram geometries, achieve a characterization of extended dual affine planes, and embed extended dual affine planes in extended projective planes. The geometries studied are rank 3 diagram geometries such that the residue of a point is a dual net, and the residue of a plane is linear; the dual of such a geometry has partitions on lines and planes which are reminiscent of parallelism of lines and planes of an affine 3-space. Examples of these geometries (some in dual form) include extended dual affine planes, Laguerre planes, 3-nets, and orthogonal arrays of strength 3. Theorem: Any such finite geometry satisfying Buekenhout's intersection property, and such that any two points are coplanar, is an extended dual affine plane (and has order 2, 4, or 10). Theorem: This geometry may be embedded in an extended projective plane of the same order.
Support effects in HDS catalysts : DFT analysis of thiolysis and hydrolysis energies of metal-support linkages

Abstract We have carried out a theoretical investigation of the active phase–support interaction for HDS catalysts using density functional theory to calculate the thiolysis and hydrolysis reaction energies for the metal–support linkages. These metal–support linkages are represented by simplified cluster models with SH or OH terminations to represent the sulfide (active) and oxide (support) phases, respectively. The calculated rank order of the supports representing Type-I (strong interaction) tendency (SiO2
Superconductivity and crystal structure of ternary CuxMo3S4 compounds with 0 ≤ x ≤ 1 prepared by anodic oxidation of Cu1.0Mo3S4

Abstract Superconductivity and crystal structure data are reported for a series of ternary CuxMo3S4 samples with 0 ≤ x ≤ 1 which were prepared by anodic oxidation of Cu1.0Mo3S4. A phase with the composition Cu0.5Mo3S4 was found to have rhombohedral lattice parameters a R = 6.447(5) A and αR = 93.74(4) ° and a superconducting critical temperature Tc = 5.8 K. The dependence of Tc on pressure for Cu0.5Mo3S4 has been measured between 0 and 19 kbar.
Consuming Sweets: The Work of Architecture in the Age of Selection Among Manufacturers' Manufactured Differences

Abstract This project refutes the view that the extensive use of manufactured products limits the space for making architecture. The strategy shown here is the construction of complete architectural solutions by coordinating the production of others. The skills required are those of the consumer. The architect as consumer develops shopping into an expertise. The impasse is not between cooption (popular reproduction of unique cultural acts), versus meaningful architecture, but between a marginalized profession and its culture's materials and methods. A meaningful style of architecture in consumer culture cannot make co-option an enemy, but must develop a full account of its relation to it.
Asymptotic equivalence of nonparametric regression and white noise model has its limits

Abstract One of the common themes of the modern nonparametric functional estimation folklore is that the signal-in-white-noise model can serve as a prototype for nonparametric regression. In this note we give an example showing that it may not always be the case
Chest radiograph in the evaluation of first time wheezing episodes : Review of current clinical practice and efficacy

ObjectiveTo evaluate the current clinical use and utility of chest radiographs (CXR) in the workup of pediatric patients with first time wheezing (FTW) episodes.SettingUrban children's hospital.DesignRetrospective review of medical records of patients seen in the emergency department in 1994 with di
During Lytic Infection Herpes Simplex Virus Type 1 Is Associated with Histones Bearing Modifications That Correlate with Active Transcription

Herpes simplex virus type 1 (HSV-1) is a large (150-kb) double-stranded DNA virus that forms latent infections in neuronal cells of the human peripheral nervous system. Previous work determined that the HSV-1 genome is found in an ordered nucleosomal structure during latent infection. However, during lytic infection, it was unclear whether viral DNA was in a chromatin state. We examined HSV-1 during lytic infection using micrococcal nuclease digestion and chromatin immunoprecipitation. The HSV-1 genome is at least partially nucleosomal, although apparently not in a regular repeating structure. Analysis of histones associated with HSV-1, within both the promoter and the transcribed regions, revealed covalent amino tail modifications similar to those associated with active host mammalian genes. Certain of the modifications were detected in the temporal order expected of the immediate-early, early, and late gene classes. These data suggest that productive infection may be accompanied by acquisition of a permissive chromatin state.
Commentary on "The Third Canadian Consensus Conference on the Diagnosis and Treatment of Dementia, 2006." Clinical guidelines are not enough: system-wide, population-based programs are needed to improve the care of patients with Alzheimer's disease and related dementias.

This issue truly represents a timely, expert, wellorganized synopsis of recent developments in the treatment and care of patients with Alzheimer’s disease, particularly from the Canadian perspective, but based on worldwide data. The purpose of this effort is to create a consensus of recommendations on relevant issues based on new knowledge. The consensus process is rigorous and clearly defined, and has a strong base of evidence. The papers and recommendations presented here cover many critical and relevant areas of recent advances in the field. Relevant clinical topics range from early detection to treatment and management of care. Ultimately, 215 recommendations were considered, and 149 recommendations were approved with strong consensus by the Canadian academic community involved in clinical research and care. I will not attempt to comment specifically on these many recommendations that were so carefully and thoughtfully evaluated by my esteemed colleagues, though in general, I certainly agree with them. Rather, my perspective will address the real value of this extensive, expensive, and time-consuming work. It is critically important to note that, quoting Dr. Chertkow in his paper, “Translating, disseminating, and implementing our recommendations received particular emphasis.” An implementation committee was created to address these “knowledge translation” issues, with a specific work plan that included publications, tool kits, and practice aids for distribution to Canadian family practitioners, course material, and “assessment of the impact o f... recommendations on clinical practice and patient outcomes.” Chertkow states,
Effect of thrombopoietin on in vitro production of megakaryocytes from fetal mouse liver cells.

Plasma clots containing fetal mouse liver cells (FMLC) were used to study the effects of a thrombocytopoiesis-stimulating factor (TSF) from kidney cell culture medium on the proliferation and maturation of megakarocytes. Cells in the megakaryocytic series were identified by the presence of acetylcholinesterase (AChE) and by their morphological and ultrastructural characteristics. For these experiments, 1 X 10(3) to 1 X 10(5) FMLC were cultured for 1-7 days with 0-5 micrograms of TSF; control cultures were treated with production medium (PMC) in which kidney cells had not been grown. The number of AChE+ cells that were observed depended upon the number of cells plated, i.e., after 6 days of culture with 5 micrograms of TSF, an average of 187 AChE+ cells was found after plating 1 X 10(4) cells and 1020 AChE+ cells were observed after plating 1 X 10(5) cells. In dose-response experiments, the number of AChE+ cells rose with increasing doses of TSF. Significantly elevated numbers of AChE+ cells were observed after the addition of 1-5 micrograms of TSF. The optimum time of culture, based upon the number of AChE+ cells found, was 3-5 days. Ultrastructural analysis of megakaryocytes in plasma clots showed evidence of platelet shedding on Day 5. After the culture of FMLC with TSF, a larger number of AChE+ cells was formed from a given number of cells plated than in previous studies that used adult bone marrow cells. Therefore, because of its greater sensitivity, FMLC may be useful for the assay of low levels of TSF, and may be a valuable tool for studying the effects of megakaryocytic regulatory factors on megakaryocytopoiesis.
Response of Coastal Bermudagrass Yield and Nutrient Uptake Efficiency to Nitrogen Sources

Nitrogen is an important agronomic input for bermudagrass production in the southern USA. Fertilizers that can efficiently provide N to grass pastures and hay meadows are an important issue because of increasing costs and environmental problems associated with N losses. This experiment was designed to determine the effectiveness of various N sources on 'Coastal' bermudagrass [Cynodon dactylon (L.) Pers.] production and N uptake efficiency. Nitrogen was applied at 0, 45, 90, and 135 kg ha -1 harvest -1 as urea-ammonium nitrate (UAN), urea, ammonium nitrate (AN) and ammonium sulfate (AS) on Gallime (Glossic Paleudalf) and Lilbert (Plinthic Paleudult) soils. Mixtures of S with UAN and of Ca and B with urea were also evaluated. Bermudagrass was periodically harvested and subsampled for total N analysis. At termination of the study soil samples were collected for pH and extractable NO 3 -N analyses. Bermudagrass yield responses to N sources were significant only in the Gallime soil. In this soil, AN and AS increased yields and resulted in greater N uptake compared to urea and UAN. Lilbert soil showed no effect of N sources on dry matter (DM) production. There was a yield response to N rates and maximum bermudagrass production was generally achieved at the 90 kg ha -1 N rate regrowth -1 . Fertilizer efficiency declined as the N rate was increased. Soil acidity increased in response to N application, particularly for the AS treatments. Selection of N sources and rates should be carefully planned to avoid detrimental effects on soil acidity and, consequently, fertilizer efficiency.
PTM-Switchboard—a database of posttranslational modifications of transcription factors, the mediating enzymes and target genes

Gene transcription is largely regulated by sequence-specific transcription factors (TFs). The TF activity is significantly regulated by its posttranslational modifications (PTMs). TF-PTMs serve as ‘molecular switchboards’ that map multiple upstream signaling events, in response to various environmental perturbations, to the downstream transcriptional events. While many instances of TF-PTMs and their effect on gene regulation have been experimentally determined, a systematic meta-analysis or a quantitative model-based investigation of this process has not been undertaken. A prerequisite to such analyses is a database of known instances of TF-PTMs affecting transcriptional regulation. The PTM-Switchboard database meets this need by cataloging such instances in the model system Saccharomyces cerevisiae. The database stores triplets of genes such that the ability of one gene (TF) to regulate a target gene is dependent on one or more PTMs catalyzed by a third gene (modifying enzyme). The database currently includes a large sample of experimentally characterized instances curated from the literature. In addition to providing a framework for searching and analyzing the data, the database will serve to benchmark computational methods. In the future, the database will be expanded to mammalian organisms, and will also include triplets predicted from computational approaches. The database can be accessed at http://cagr.pcbi.upenn.edu/PTMswitchboard.
Additive decomposition of nonnegative matrices with applications to permanents and scalingt

Let U1 and U2 be compact subsets of m × n nonnegative matrices with prescribed row sums and column sums. Given A in U2 , we study the quantity and the matrices B in U1 that satisfy A−μ(U1;A)B is nonnegative.The quantity is determined. Using the results obtained, we give a lower bound for the permanent of nonnegative matrices. Moreover, we study the scaling parameters of nonnegative matrices. An upper bound and an extremal characterization for their product are given.
Quantification of Preoperative Stone Burden for Ureteroscopy and Shock Wave Lithotripsy: Current State and Future Recommendations

Objectives To determine which preprocedure imaging modality was used and how the stone burden quantification was assessed before shock wave lithotripsy (SWL) and ureteroscopy (URS) in published studies. Material and Methods References were searched in the MEDLINE database using the terms “shock wave lithotripsy” and “ureteroscopy,” excluding “percutaneous nephrolithotomy” from January 2007 to January 2009. The inclusion criteria for our study included clinical trials published in English with >20 patients and measurement of pretreatment stone size. Results Of the 198 studies in our initial MEDLINE search, 101 met the inclusion criteria. Of the 101 studies, 61 had evaluated SWL and 40 had evaluated URS. Also, 78 studies (77%) had quantified the stone burden in 1 dimension, 19 (19%) in 2 dimensions, and 4 (4%) in 3 dimensions. For SWL, the imaging modalities used to assess the stone burden included 24 mixed (40%), 10 noncontrast-enhanced computed tomography (16%), 12 plain abdominal film (20%), and 5 intravenous urography (8%); 10 studies (16%) did not mention the imaging modality used. For URS, the imaging modalities used to assess the stone burden included 15 mixed (38%), 8 noncontrast-enhanced computed tomography (20%), and 3 plain abdominal film (7%); 14 studies (35%) did not mention the imaging modality used. Conclusions Heterogeneity exists in the published data regarding the imaging modality used both before URS and SWL. Up to one third of all studies for both URS and SWL did not mention the imaging modality used to quantify the stone burden. Standardization of preprocedure imaging and its reporting in published studies is needed to better assess the pretreatment stone burden and compare the treatments of stone disease.
The evolution of resistance to two-toxin pyramid transgenic crops

Pyramid transgenic crops that express two Bacillus thuringiensis (Bt) toxins hold great potential for reducing insect damage and slowing the evolution of resistance to the toxins. Here, we analyzed a suite of models for pyramid Bt crops to illustrate factors that should be considered when implementing the high dose-refuge strategy for resistance management; this strategy involves the high expression of toxins in Bt plants and use of non Bt plants as refuges. Although resistance evolution to pyramid Bt varieties should in general be slower, resistance to pyramid Bt varieties is nonetheless driven by the same evolutionary processes as single Bt-toxin varieties. The main advantage of pyramid varieties is the low survival of insects heterozygous for resistance alleles. We show that there are two modes of resistance evolution. When populations of purely susceptible insects persist, leading to density dependence, the speed of resistance evolution changes slowly with the proportion of refuges. However, once the proportion of non-Bt plants crosses the threshold below which a susceptible population cannot persist, the speed of resistance evolution increases rapidly. This suggests that adaptive management be used to guarantee persistence of susceptible populations. We compared the use of seed mixtures in which Bt and non-Bt plants are sown in the same fields to the use of spatial refuges. As found for single Bt varieties, seed mixtures can speed resistance evolution if larvae move among plants. Devising optimal management plans for deploying spatial refuges is difficult because they depend on crop rotation patterns, whether males or females have limited dispersal, and other characteristics. Nonetheless, the effects of spatial refuges on resistance evolution can be understood by considering the three mechanisms determining the rate of resistance evolution: the force of selection (the proportion of insects killed by Bt), assortative mating (deviations of the proportion of heterozygotes from Hardy-Weinberg equilibrium at the total population level), and male mating success (when males carrying resistance alleles find fewer mates). Of these three, assortative mating is often the least important, even though this mechanism is the most frequently cited explanation for the efficacy of the high dose-refuge strategy.
Ethics in community-based environmental epidemiology and public health practice: some considerations

Community-based environmental epidemiology poses a variety of ethical challenges. These include issues of data disclosure, whistle-blowing, responsiveness to public versus scientific agendas, and the acknowledgement of the limitations of scientific investigation. Little is written for the practitioner, and little training or discussion is available. Yet, this is an issue of great importance to the field of public health. Openness and honesty with the community studied are essential if environmental epidemiology is to maintain public credibility.
Morphological Control of Highly Ordered Mesoporous Silica SBA-15

Highly ordered hexagonal mesoporous silica SBA-15 with fiber, rope, donut, sphere, gyroid, and discoid-like morphology have been synthesized.
An experimental investigation of the photoconductivity of lead halides

The photoconductivity of PbX2 and PbFX (X = Cl, Br) single crystals is investigated at 80 and 8 K in the spectral region 3.0 to 5.5 eV. The spectral dependence of the photoconductivity is studied with ohmic contacts, while photodiffusion voltages and the range of the mobile charge carriers are studied with insulating contacts. The former is discussed in conjunction with reported luminescence data on these halides. The present study reveals that in both photoconductivity and luminescence the role of impurities is pertinent. One possible impurity is the oxide ion. In both binary and the ternary halides photoholes constitute the mobile photoexcited charge carriers. Es wird die Photoleitung in PbX2 und PbFX (X = Cl, Br)-Einkristallen zwischen 3,0 und 5,5 eV bei 80 und 8 K untersucht. Die Spektralabhangigkeit der Photoleitung wird mit Ohmschen Kontakten untersucht, wahrend Photodiffusionsspannungen und der Schubweg der beweglichen Ladungstrager mit isolierenden Kontakten gemessen werden. Die Spektralabhangigkeit der Photoleitung wird mit veroffentlichten Lumineszenzdaten dieser Halogenide verglichen. Diese Unter-suchung ergibt, das in der Photoleitung sowie in der Lumineszenz die Verunreinigungen eine wichtige Rolle spielen. Eine mogliche Verunreinigung ist das Oxid-Ion. In den binaren und ternaren Halogeniden sind die Photolocher die beweglichen Ladungstrager.
Octrees of objects in arbitrary motion: representation and efficiency

An algorithm is presented that updates the octree of a three-dimensional object after the object has undergone arbitrary rotation and translation. The algorithm moves each of the black leaves and then adds the subtree corresponding to the displaced black leaf. The algorithm uses a computationally efficient method to detect the intersections of moved blocks with octree tessellation. On the average, the space and time complexities of the algorithm are both bounded by O(Kn), where K is the number of nodes in the source tree and n is the logarithm of the side-length of the universe space. The quantization errors are prevented from accumulating by maintaining a compact source octree. Each incremental displacement is performed with respect to the source tree. Implementation results are given for the motion of synthetic three-dimensional objects. Upper bounds are derived for the numbers of nodes in an octree representing a cubic block of arbitrary orientation and position. These bounds are proportional to the face area of the cube plus the logarithm of the side length of the universe space.
Mechanisms of infectious diarrhea

Infectious diarrhea is an important public health problem worldwide. Research has provided new insights into the mechanisms of diarrhea caused by various pathogens that are classified as noninflammatory, inflammatory or invasive. These three groups of organisms cause two diarrheal syndromes--noninflammatory diarrhea and inflammatory diarrhea. The noninflammatory diarrheas are caused by enterotoxin-producing organisms such as Vibrio cholerae and enterotoxigenic Escherichia coli, or by viruses that adhere to the mucosa and disrupt the absorptive and/or secretory processes of the enterocyte without causing acute inflammation or mucosal destruction. Inflammatory diarrhea is caused by two groups of organisms--cytotoxin-producing, noninvasive bacteria (e.g. enteroaggregative Escherichia coli, enterohemorrhagic Escherichia coli and Clostridium difficile), or by invasive organisms (e.g. Salmonella spp., Shigella spp., Campylobacter spp., Entamoeba histolytica). The cytotoxin-producing organisms adhere to the mucosa, activate cytokines and stimulate the intestinal mucosa to release inflammatory mediators. Invasive organisms, which can also produce cytotoxins, invade the intestinal mucosa to induce an acute inflammatory reaction, involving the activation of cytokines and inflammatory mediators. Regardless of the underlying mechanism they use, these various types of pathogen have all successfully evolved to evade and modulate the host defense systems. The mechanisms by which the different pathogens invade the host and cause infectious diarrhea are the topic of this Review.
A Three-Layer Diffusion Model as Applied to Unstable Atmospheric Conditions

Abstract A three-layer numerical model, incorporating the ideas of forced, free, and windless convection, is constructed for use in the two-dimensional diffusion equation for steady state conditions. The eddy diffusivity of momentum Km in the first layer is that given by Monin and Obukhov, while in the second layer Km is proportional to the 4/3; power of the height z. In the third layer Km ∝ z2. The wind velocity profiles developed for the model are consistent with the definition of the eddy diffusivity of momentum for the layer of constant shearing stress. The numerical model is tested for its reliability by comparing numerical results with analytic results attained under the same conditions. The model is then applied to the unstable Project Prairie Grass gas diffusion data in order to see if the model can account for the observed cross-wind integrated concentration c. A satisfactory comparison between the predicted and the observed field of c is obtained. The exceptions are those cases exhibiting grea...
Arterial windkessel parameter estimation: A new time-domain method

We developed and validated a new, more accurate, and easily applied method for calculating the parameters of the three-element Windkessel to quantitate arterial properties and to investigate ventriculoarterial coupling. This method is based on integrating the governing differential equation of the three-element Windkessel and solving for arterial compliance. It accounts for the interaction between characteristic impedance and compliance, an important phenomenon that has been ignored by previously implemented methods. The new integral method was compared with four previously published methods as well as a new independent linear least-squares analysis, using ascending aortic micromanometric and volumetric flow measurements from eight dogs. The parameters calculated by the new integral method were found to be significantly different from those obtained by the previous methods but did not differ significantly from maximum likelihood estimators obtained by a linear least-squares approach. To assess the accuracy of parameter estimation, pressure and flow waveforms were reconstructed in the time domain by numerically solving the governing differential equation of the three-element Windkessel model. Standard deviations of reconstructed waveforms from the experimental ensemble-averaged waveforms, which solely reflect the relative accuracy of the Windkessel parameters given by the various methods, were calculated. The new integral method invariably yielded the smallest error. These results demonstrate the improved accuracy of our new integral method in estimating arterial parameters of the three-element Windkessel.
CHROMOSOMAL DEFICIENCIES IN DATURA STRAMONIUM INDUCED BY COLCHICINE TREATMENT

OUR PREVIOUS accounts of effects of colchicine on plants have been limited to its use as a means of doubling the total chromosome number. In this paper and others to follow, effects other than simple doubling will be discussed. When seeds are soaked in solutions of colchicine for varying lengths of time, different cells in the epicotyl may be affected differently. Consequently the plant that develops may be a chimera of one sort or another. Mixochimeras consist of a mixture of tissue of different chromosomal constitution. In addition, the chromosome number in cells in one germ layer may be different from that of cells in other layers, producing periclinal chimeras. About half of the plants in this experiment were recorded as sectorial chimeras, having one or more aberrant sectors. Plants were found of which a sector was also a periclinal or mixochimera or both. The egg cells and pollen grains are derived from a single layer of cells directly below the epidermis. The present paper is concerned with the chromosome condition of this subepidermal layer as shown by a study of pollen-mother-cells of abnormal-appearing plants or sectorial chimeras which showed chromosomal deficiencies or duplications. In the summer of 1938 field records were made on 2,135 Datura stramonium plants grown from Line 1 seeds which had been soaked for three to eight days 1 Received for publication May 15, 1940. in solutions containing 0.2 and 0.4 per cent colchicine. The results are shown in table 1. In the series with the weaker concentration, the treatment had little effect upon the percentage of germination but with the higher concentrations and longer treatments, germination was reduced. Not all of the seedlings were grown to maturity. Since a roughened, thick leaf structure is often associated with polyploidy, selection was made on the basis of the appearance of the seedlings. Those which looked more or less normal or whose leaves were only slightly roughened were discarded. From the lot treated four days with 0.2 per cent solution, 384 seedlings were discarded; from the lot treated five days with 0.2 per cent solution, 108 were discarded and from the lot treated six days with 0.4 per cent solution, 214 were discarded. All the remaining seedlings were planted in the field. Some died before reaching maturity. Field records were made on 2,135 mature plants. From the higher dosages, from 50 to 75 per cent of the plants were abnormal in appearance, mostly 4n or "tetraploids" of some sort, of which nearly half showed from one to four aberrant sectors. Among the 2n or 2n + 1 offspring are included those types which were recognized as any of the twelve 2n + 1 types. Some of the 2n + 1 types were not recognized because the epidermis was 44n (periclinal chimeras) or because the plant
An Experiment For Measuring Effect Of Atmospheric Turbulence On A Vertical Optical Path

The experiment to be described is intended to obtain a measure of the limit on the phase coherent propagation of light along a vertical path from a point source. This experiment utilizes an argon laser to generate a pair of coherent point sources in an aircraft. These sources generate a fringe pattern on the ground. As the aircraft flies along a track over a set of ground detectors, a frequency modulated signal is generated in the photoelectric detectors, the frequency modulation being proportional to the phase shift difference along the two paths from the plane. A Fourier transform of the data produces a measure of the phase coherence function or the Atmospheric Transfer Function of the atmospheric path. A modification of the direct experiment uses polarized sources in the transmitter to permit reconstruction of the phase difference function along the paths. From this data, the statistical parameters of the phase structure and log-amplitude behaviour can be obtained.© (1976) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Inversion Of The Generalized Radon Transform

The problem of determining a function from known integrals of that function over hyper-surfaces (curves in 2D case) leads to the notion of the generalized Radon transform. We treat this problem and describe the inversion procedure. It is shown that the problem of inversion of the generalized Radon transform can be reduced to solving a Fredholm integral equation. Also, we consider some applications. In particular, we estimate the error of Shepp-Logan's filter used in Computerized X-ray Tomography, present inversion formulae for Exponential and Attenuated Radon transforms, and consider the example of the Hyperbolic Radon transform.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Undergraduate nursing student experience

The purpose of the present qualitative study was to describe and explicate the experience of being a nursing student. A convenience sample of 12 nursing students from a variety of backgrounds at a public university were interviewed using an interview guide with open-ended questions. Their stories provided an insight into the satisfactions, challenges and stresses faced by students. Four major theme clusters emerged from the data: (i) meeting conflicting demands; (ii) feeling overworked; (iii) feeling unprepared and; (iv) seeking respect and support from one's faculty. These identified themes corroborate the findings of other researchers who have studied the student experience. Student's stories provide insights into the current educational environment, which can assist faculties to understand the impact of their pedagogical approaches. This information is particularly important in light of the current worldwide nursing shortage.
Evaluation of magnetic resonance imaging sensitivity in patients with relapsing remitting multiple sclerosis: baseline versus Betaseron treatment trials.

From the 1Laboratory of Diagnostic Radiology Research, Office of Intramural Research, and 2Neuroimmunology Branch, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, MD; and 3Hospital of the University of Pennsylvania, Philadelphia, PA. Address reprint requests to J. A. Frank, MD, OD OIR LDRR, Bldg. 10, Rm. B1N256, 10 Center Dr., MSC 1074, Bethesda, MD 20854-1074.
Angioplasty versus intravenous thrombolysis for acute myocardial infarction

Abstract [Gallagher EJ. Angioplasty versus intravenous thrombolysis for acute myocardial infarction. Ann Emerg Med. March 2002;39:299-301.]
Sex differences in development of morphine tolerance and dependence in the rat

Rationale: Several investigators have shown that male rodents are more sensitive than females to morphine’s antinociceptive effects. Objective: The present study was conducted to determine whether this sex difference is stable after chronic morphine treatment. Results: Acutely administered morphine produced significantly greater hotplate and tail withdrawal antinociception in males than in females. In contrast, there were no sex differences in morphine’s hotplate or tail withdrawal effects under repeated (1-week interval) dosing conditions. In a separate group of rats, after 2 weeks of twice-daily morphine treatment (10–20 mg/kg per injection), the ED50 for morphine’s antinociceptive effects increased approximately 6.9-fold in males versus only 3.7-fold in females; chronic morphine treatment also disrupted the estrous cycle of females. In a separate group of rats treated with 10 mg/kg morphine twice daily for 5 days, treatment with naloxone (1.0 mg/kg) on day 6 produced greater withdrawal scores in males than in females. Conclusions: These experiments demonstrate sex differences in development of tolerance to and dependence on morphine in the rat.