cssi/SciSciGPT-SciSciNet huggingface dataset:
Atomic force microscopy of DNA and bacteriophage in air, water and propanol: the role of adhesion forces

We have developed a chemical treatment for the mica surface which allows biopolymers to be held in place for atomic force microscopy, even under water, using conventional, untreated force sensing tips. We illustrate the procedure with images of lambda DNA and fd phage. The phage adheres well enough to permit in situ imaging of the adsorption process in water. These experiments yield a mean length for the phage of 883 +/- 72 nm. This compares with a measured length of 883 +/- 33 nm when the phage are imaged after drying following adsorption from water, showing that the effect of dehydration is quite small. Adhesion forces between the force sensing tip and the substrate and the sensing tip and the biomolecules are very different in the three media (air, water and propanol). The apparent height of the phage and the width and height of the DNA depends upon these adhesion forces quite strongly. In contrast, changing the Hookean spring force exerted by the scanning tip makes little difference. These results suggest that the chemical factors involved in adhesion can dominate atomic force images and that the composition of the scanning tip is at least as important a factor as its geometry.
Sources for a Judaica Reference Collection

The compilation of a core collection for Jewish reference sources raises a number of questions which must be confronted and answered. Should a Jewish reference collection be a listing of sources for the study of Judaism primarily as a religion, or primarily as a cultural group? Should the sources be leaning toward Biblical and Rabbinic studies or towards history, art, and music? For the purposes of this bibliography, I have chosen to concentrate on the cultural aspects of Judaism and Jews as a group to be studied. As such I have elected, somewhat arbitrarily, to exclude the primary sources of the study of Judaism as a religion, these sources being a Jewish version of an English translation of the Bible, an English copy of the Talmud, liturgies, and all of the supplementary primary sources which would be necessary. It is hoped, instead, that those items would be found in the religion section of the reference collection. Nevertheless, this core collection will provide the tools for any interested person seeking to include such sources in their Judaic reference collection.
Expression of class I homeobox genes in fetal and adult murine skin

We examined the expression patterns of several class I homeobox genes in mouse fetal and adult skin. All the genes of the Hox-B locus, except Hoxb-1, are expressed in skin from murine fetuses of 17 and 18 d gestation, at which time the epidermis is undergoing stratification and differentiation. The amount of individual Hox gene message varies considerably, but expression of all genes is detectable by RNase protection except Hoxb-1, which could not be detected even by the reverse transcription-polymerase chain reaction (RT- PCR) assay. Homeobox gene expression in skin is not confined to the Hox-B locus; the paralogous genes Hoxa-4, -b-4, -c-4, and -d-4 are all expressed. The amount of Hoxb-4, -b-2, and -c-4 message in skin is relatively constant from the earliest gestational day examined (day 16) through birth at day 19. Expression of several homeobox genes is also seen in adult skin.
Some possible modifications of the α-helix configuration involving changes of direction and sense of the helix

Abstract An investigation has been made by use of atomic models of some possible simple modifications of the α-helix configuration. It is concluded that relatively slight modifications such as a change of senses of the helix permit the formulation of specific structures which circumvent some of the limitations of the simple α-helix with respect to protein structure, and furthermore that these specific structures accord well with many general ideas on protein structure which have been previously proposed on chemical and other evidence.
Notch1 Regulates the Effects of Matrix Metalloproteinase-9 on Colitis-Associated Cancer in Mice

Background & Aims Inflammatory bowel disease increases the risks of colon cancer and colitis-associated cancer (CAC). Epithelial cell–derived matrix metalloproteinase (MMP)-9 mediates inflammation during acute colitis and the cleavage and activation of the transcription factor Notch1, which prevents differentiation of progenitor cells into goblet cells. However, MMP-9 also protects against the development of CAC and acts as a tumor suppressor. We investigated the mechanisms by which MMP-9 protects against CAC in mice. Methods C57/B6 wild-type mice were given a single dose of azoxymethane and 2 cycles of dextran sulfate sodium (DSS). Mice were also given the γ-secretase inhibitor difluorophenacetyl-l-alanyl- S -phenylglycine t-butyl ester (DAPT) or dimethyl sulfoxide (control) during each DSS cycle; they were killed on day 56. We analyzed embryonic fibroblasts isolated from wild-type and MMP-9 −/− mice and HCT116 cells that were stably transfected with MMP-9. Results Wild-type mice were more susceptible to CAC following inhibition of Notch1 by DAPT, shown by increased numbers of tumors and level of dysplasia compared with controls. Inhibition of Notch1 signaling significantly reduced protein levels of active Notch1, p53, p21 WAF1/Cip1 , Bax-1, active caspase-3, as well as apoptosis, compared with controls. Similar results were observed in transgenic HCT116 cells and embryonic fibroblasts from MMP-9 −/− mice on γ-radiation–induced damage of DNA. Conclusions MMP-9 mediates Notch1 signaling via p53 to regulate apoptosis, cell cycle arrest, and inflammation. By these mechanisms, it might prevent CAC.
Nurse Turnover in the Newborn Intensive Care Unit

Nurse retention has become a significant issue in the newborn intensive care units for two main reasons: 1) the quality of care declines as it is delivered by inexperienced nurses, and 2) the cost of orienting new nurses is exorbitant. “Stress” has been implicated as one of the important factors in nurse retention; it appears that a paradox exists in that the stress/excitement that attracts a nurse to the newborn ICU in the first place may Ultimately drive her away. We attempted to define stress factors in the Turner Newborn Intensive Care Unit at Hermann Hospital in Houston, Texas, and to develop management methods to decrease stress. Over a three-year period, during the implementing of new programs, nurse termination rates decreased significantly, as did turnover.
Age-related changes in ultrastructure and chemical composition associated with changes in heat resistance of Neosartorya fischeri ascospores

Ascospores (10 5 /ml) of Neosartorya fischeri var. glaber (FRR 1833) harvested from grape juice agar after 11 d of incubation at 30°C were inactivated by treatment at 82° for 60 min; 25-day-old ascospores survived this heat treatment. To determine if differences in ultrastructure and chemical composition might be related to differences in heat-resistance, ultrastructure as well as protein, lipid, sugar and polyol contents of 11-day-old (heatsensitive) and 25-day-old (heat resistant) ascospores were compared. SEM revealed little difference in external appearance, whereas TEM revealed some internal differences between 11- and 25-day-old ascospores, particularly in the region of germ-tube initiation. Significant qualitative differences in protein content between heat-sensitive and heat-resistant ascospores were observed. The lipid and fatty acid compositions of the two types of ascospore were similar. Heat-resistant ascospores contained higher levels of glycerol, mannitol and trehalose than heat-sensitive ascospores, suggesting that the lowering of internal water activity or membrane stabilization may partially account for increased heat resistance.
PCP4 Is a Key Regulator of Cardiac Purkinje Cell Calcium Homeostasis and Suppresses Arrhythmogenic Calcium Waves

Background Triggered activity in cardiac Purkinje cells (PCs) has been implicated in the genesis of inherited and acquired ventricular arrhythmias. PC arrhythmogenicity is attributed, at least in part, to dysregulation of intracellular calcium homeostasis; however, the molecular basis for differential calcium handling in PCs vs ventricular myocytes (VMs) is incompletely characterized. The goal of this study was to identify and characterize novel molecular mechanisms responsible for altered calcium handling in PCs. Methods and Results Compound transgenic mice harboring both a Cntn2-eGFP BAC reporter and an α-MHC-Cre/floxed tdTomato reporter were used to isolate cardiac PCs (eGFP + /tomato + ) from VMs (eGFP – /tomato + ) by FACS. Gene profiling was performed on total RNA extracted from each cell population. The transcript encoding Purkinje cell protein 4 ( PCP4 ), a modulator of calmodulin-dependent signaling, was significantly enriched in PCs. Restricted expression of PCP4 protein in PCs was confirmed by immunohistochemistry. PCP4 knockout mice were obtained and crossed with the Cntn2-eGFP reporter mouse, and isolated VMs and PCs from wild-type (WT) and mutant hearts were distinguished by epifluorescence and intracellular Ca 2+ dynamics recorded by microfluorometry. PCP4 –/– PCs displayed significantly slower kinetics of relaxation [τ(decay)] than that observed in wild-type PCs (328.9 ± 24.9 ms vs 235.8 ± 20.7 ms, P PCP4 –/– ) PCs were also more likely to develop rate dependent early aftertransients [63.6% (21/33) vs 8.3% (3/36) at 0.5 Hz, P P PCP4 –/– ) mice elicited PVCs (4/5, P Conclusions PCP4 is preferentially expressed in the murine ventricular conduction system, where it modulates intracellular calcium homeostasis. Loss of function of PCP4 results in an increased propensity for the development of early and delayed aftertransients and triggered arrhythmias.
Parametric study of stress-intensity factors in bonded composite stringer panels

Stress-intensity factors are determined for an infinite cracked orthotropic sheet adhesively bonded to an orthotropic stringer. Since the stringer is modeled as a semi-infinite sheet, the solution is most appropriate for a crack tip located near a stringer edge. Both adherends are treated as homogeneous, orthotropic media which are representative of many fiber-reinforced composite materials. The complex variable theory of elasticity was used to obtain a set of integral equations describing the problem. The integral equations are replaced by an equivalent sheet of algebraic equations, which are solved to obtain the shear stress distribution in the adhesive layer. From these adhesive stresses, the stress-intensity factors are found. A parametric study is conducted to determine the sensitivity of the system to material properties and specimen configuration. Unless the crack tip is very close to or under the stringer, the stress-intensity factor is approximately that of the unstiffened sheet. However, as the crack propagates beneath the stringer, the stress-intensity factor decreases significantly. Increasing the stringer stiffness or the adhesive stiffness also decreases the stress-intensity factor.
Using the Knowledge Quartet to quantify mathematical knowledge in teaching: the development of a protocol for Initial Teacher Education

This study examined trainee teachers' mathematical knowledge in teaching (MKiT) over their final year in a US Initial Teacher Education (ITE) programme. This paper reports on an exploratory methodological approach taken to use the Knowledge Quartet to quantify MKiT through the development of a new protocol to code trainees' teaching of mathematics lessons. This approach extends Rowland's et al. work on the Knowledge Quartet (KQ). Justification for using the KQ to quantify MKiT, and the potential benefits such an attempt might provide those involved with ITE, are discussed. It is suggested that quantified MKiT data based on the Knowledge Quartet can be used to consider MKiT development in novice teachers in order to inform ITE programmes and form new theoretical loops between theory and practice in teacher education.
Multiply enhanced non-parametric four-wave mixing spectroscopy☆

Abstract A three-laser technique for performing fully resonant, non-parametric four-wave mixing is demonstrated in pentacene-doped benzoic acid at 2 K. The technique does not have interference from fluorescence but it is predicted to have the capability for resolution within an inhomogeneously broadened molecular line.
A Hybrid Approach to Data Clustering Analysis with K-Means and Enhanced Ant-Based Template Mechanism

Data clustering algorithms play an important role in effective analysis and organization of massive amounts of information. The K-means algorithm is the most commonly used partitional data clustering algorithm because of its simplicity in implementation and its high convergence rate. However, it suffers from the inability to always converge to the global optima, depending on how the data items are distributed initially. Ant-based Template Mechanism (Ant_TM) is another frequently used clustering algorithm, but it exhibits two major weaknesses in convergence rate and data purity of clustering results. In this paper, we first present a modification to the original Ant_TM to encourage formation of new cluster regions that enables the clustering result to move away from local optima. Second, we present two hybrid clustering algorithms based on the enhanced Ant-based Template Mechanism (Ant_TM) and the K-means algorithms. The rationale is that the integration of the K-means algorithm can speed up the convergence process and provide a perturbance to break free from local optimum clustering. We conduct experiments to compare the performance of our hybrid algorithms, against the enhanced Ant TM and the K-means algorithm, as well as the PSO+K and GA. The result shows that our algorithms outperform the original Ant_TM, K-means, and PSO+K, and is competitive against the GA in terms of the more compact and better separated clusters.
An analysis of the time scales associated with aerosol processes during dry deposition

A fundamental assumption of air quality and process-level deposition models is that, with the exception of deliquescent behavior, the aerosol size distribution is invariant during the dry deposition process, and hence the deposition calculation can be effectively decoupled from the rest of the aerosol dynamics. However, this assumption may be violated due to the changing physical and chemical regimes close to the receptor surface. To determine whether aerosol dynamics might be responsible for violations of the constant flux layer assumption and thus the observed discrepancy between observed and model-predicted, size-resolved aerosol dry deposition velocities (Vd), we undertake a series of model experiments to quantify the time scales of aerosol dynamic processes relative to size-resolved aerosol Vd. The results indicate that using the model formulation of Slinn or alternative published formulations for the components of dry deposition, both intermodal coagulation and condensation of semivolatile compounds...
Berezinskii-Kosterlitz-Thouless transition in a trapped quasi-two-dimensional Fermi gas near a Feshbach resonance

We study the superfluid transition in a quasi-two-dimensional Fermi gas with a magnetic field tuning through a Feshbach resonance. Using an effective two-dimensional Hamiltonian with renormalized interaction between atoms and dressed molecules, we investigate the Berezinskii-Kosterlitz-Thouless transition temperature by studying the phase fluctuation effect. We also take into account the trapping potential in the radial plane and discuss the number and superfluid density distributions. These results can be compared to experimental outcomes for gases prepared in one-dimensional optical lattices.
Dual quaternions, rigid body mechanics, and powered-descent guidance

In this paper, we present a Lyapunov-based framework for the analysis of unconstrained and constrained coupled rotational and translational control problems. Autonomous control algorithms for constrained coupled rotational and translational motions are challenging to design as they involve dependent variables that evolve in distinct configuration spaces. In the meantime, the unit dual quaternion parameterization can capture this dependency. Using this parameterization, we develop an array of globally stable control laws for unconstrained and constrained rigid body dynamics via a convex energy like Lyapunov function on dual quaternions. Furthermore, we characterize the convex representable subset of unit dual quaternions that corresponds to translational and rotational states that satisfy a predefined field of view constraints with respect to the body frame. We then proceed to construct a convex logarithmic barrier function on these constrained sets, which is subsequently used for the synthesis of the translational and rotational control laws for a wide range of applications. Powered-descent guidance problem is discussed as a potential application for the proposed framework.
Generation of new intercellular junctions between cardiocytes. A possible mechanism compensating for mechanical overload in the hypertrophied human adult myocardium.

Abstract Intercellular dehiscence is a common cardiocytic response to pathological conditions. However, little consideration has been given to the possibility of new intercellular junctions developing between cardiocytes within developed myocardium. To examine this possibility as it may relate to useful compensation for hemodynamic overloads, changes in cardiocytic connection were evaluated by scanning electron microscopy in hypertrophied myocardium of adult human hearts. Transmural myocardium of left ventricle was obtained at autopsy from five hearts with concentric hypertrophy, five hearts with eccentric hypertrophy, and five control hearts (noncardiac death). After formalin fixation, the number of cardiocytes connected to an individual cardiocyte was counted in tissues from the middle portion of the transmural samples by scanning electron microscopy. Cardiocytic diameter and connective tissue volume fraction were measured on the transmural sections by light microscopy. In concentrically hypertrophied h...
When is nonadaptive information as powerful as adaptive information

Information based complexity is a unified treatment of problems where only partial or approximate information is available. In this approach one states how well a problem should be solved and indicates the type of information available. The theory then tells one optimal information and optimal algorithm and yields bounds on the problem complexity. In this paper we survey some recent results addressing one of the problems studied in information based complexity. The problem deals with nonadaptive and adaptive information both for the worst case and average case settings.
Frequency Monitoring of Hemoglobin A1c, Low-Density Lipoprotein, and Urine Protein Laboratory Testing: A College of American Pathologists Q-Probes Study

Context.—Ensuring laboratory tests are performed at intervals consistent with established, evidence-based guidelines in diabetic patients is an important aspect of laboratory utilization. Objectives.—To measure how frequently diabetes mellitus patients are tested for hemoglobin A1c (HbA1c), low-density lipoprotein, and urine protein and to determine whether the frequencies with which these analytes are tested are consistent with recognized guidelines. Design.—Participants prospectively identified up to 40 patients with a current HbA1c result and at least 2 previous measurements within the past 24 months. For each patient identified with at least 3 HbA1c measurements during a 24-month period, participants also determined the number of low-density lipoprotein and spot or random urine protein tests that were performed during those 24 months. Results.—Participants from 49 institutions submitted a total of 1915 cases that met the study criteria of at least 3 HbA1c test results within the past 24 months. Approx...
Wnt-dependent de novo hair follicle regeneration in adult mouse skin after wounding

The mammalian hair follicle is a complex 'mini-organ' thought to form only during development; loss of an adult follicle is considered permanent. However, the possibility that hair follicles develop de novo following wounding was raised in studies on rabbits, mice and even humans fifty years ago. Subsequently, these observations were generally discounted because definitive evidence for follicular neogenesis was not presented. Here we show that, after wounding, hair follicles form de novo in genetically normal adult mice. The regenerated hair follicles establish a stem cell population, express known molecular markers of follicle differentiation, produce a hair shaft and progress through all stages of the hair follicle cycle. Lineage analysis demonstrated that the nascent follicles arise from epithelial cells outside of the hair follicle stem cell niche, suggesting that epidermal cells in the wound assume a hair follicle stem cell phenotype. Inhibition of Wnt signalling after re-epithelialization completely abrogates this wounding-induced folliculogenesis, whereas overexpression of Wnt ligand in the epidermis increases the number of regenerated hair follicles. These remarkable regenerative capabilities of the adult support the notion that wounding induces an embryonic phenotype in skin, and that this provides a window for manipulation of hair follicle neogenesis by Wnt proteins. These findings suggest treatments for wounds, hair loss and other degenerative skin disorders.
A transdominant tat mutant that inhibits tat-induced gene expression from the human immunodeficiency virus long terminal repeat.

Abstract Regulation of human immunodeficiency virus (HIV) gene expression is dependent on specific regulatory regions in the long terminal repeat. These regions include the enhancer, SP1, "TATA," and trans-activating (TAR) regions. In addition, viral regulatory proteins such as tat and rev are important in regulating HIV gene expression. The mechanism of tat activation remains the subject of investigation, but effects at both transcriptional and posttranscriptional levels seem likely. Previous mutagenesis of the tat protein revealed that the amino terminus, the cysteine-rich domain, and the basic domain were all required for complete tat activation. Mutants of other viral trans-acting regulatory proteins, including E1A, tax, and VM65, have been identified that were capable of antagonizing the activity of their corresponding wild-type proteins. We wished to determine whether mutants of the tat protein could be identified that exhibited a similar phenotype. One mutant (delta tat) that truncated the basic domain of tat resulted in a transdominant phenotype inhibiting tat-induced gene expression of the HIV long terminal repeat but not other viral promoters. This mutant exhibited its maximal phenotype in cotransfection experiments when present in an 8- to 30-fold molar excess over the wild-type tat gene. Trans-activation of the HIV long terminal repeat by delta tat was very defective at the DNA concentrations used in these experiments. RNase protection analysis indicated that this mutant decreased tat-induced steady-state mRNA levels of the HIV long terminal repeat. Second-site mutations of the delta tat gene in either the amino terminus or cysteine region eliminated the transdominant phenotype. In contrast to tat, which was localized predominantly to the nucleolus, delta tat was present in both the nucleus and cytoplasm, suggesting that it may inhibit tat function by preventing nucleolar localization. Transdominant mutants of tat may have a role in potentially inhibiting HIV gene expression.
Effect of free carrier screening on the binding energy of D− centers in polar semiconductors

Abstract A calculation of the binding energy of a D − center, defined as the energy required to remove one of the two electrons from the D − center to infinity, in the presence of other free carriers is reported in polar crystals. It is assumed that the effective interaction between each of the two electrons and the positive ion is described by Thomas-Fermi potential. The effective interaction between the two electrons in polar crystals is, however, described by two recently proposed potentials. The binding energy of a D − ion is calculated variationally in several polar crystals as a function of the screening parameter δ and the value of δ at which the binding energy goes to zero ( D − Mott transition) is determined. A possible experimental situations where this system may be studied is discussed.
Lessons learned implementing a regional health information exchange in Geneva as a pilot for the Swiss national eHealth strategy

It took more than ten years from the initial mandate to the first implementation of e-toile, the Geneva health information exchange. Although most actors quickly agreed on the goals and potential benefits of such a system, obstacles were many, and mostly non-technical. The transparency resulting from a streamlined exchange of information may improve the continuity, quality and efficiency of care, while, at the same time, reveal and challenge habits and practices of care professionals and of citizens. This tension must be understood, and trust must be fostered amongst stakeholders. In our experience, key enablers were the collaborative elaboration and negotiation of an eHealth law, the definition of an eHealth strategy, as well as the involuntary increased financial pressure on all healthcare stakeholders. Nevertheless, and even though it is often cited as a successful model, the Swiss health system, being highly fragmented and based on a complex interplay of private and public stakeholders, is not as conducive to the deployment of eHealth systems as most other developed countries.
Policies, plans, practice, and prospects: irrigation in northeastern Syria

Over the past half-century the agricultural landscape of northeastern Syria has been transformed, due in large part to the introduction of significant irrigation to the steppe. At the beginning of this period, irrigation was confined almost entirely to river floodplains and natural depressions. The steppe was dominated by wintertime rain-fed agriculture and year-round grazing. The introduction of diesel-powered wells and, subsequently, state-operated dam and canal systems, has led to the expansion of both wintertime and summertime irrigation on the steppe away from the floodplain. The sustainability of these irrigation projects has always been suspect. Even as technologies for water extraction have allowed for previously impossible patterns of cultivation, the combination of declining water quality, a deepening water-table, and degradation-prone soils have limited crop yields and led to the rapid abandonment of many steppe farms. The actual trajectory of land-use in the region is determined by social and political forces as well as by hydrology and surficial geology. In this paper we examine recent land-use history in the watersheds of two tributaries of the Euphrates River, the Balikh and Khabur. A review of historical drivers of development in the region is combined with satellite analyses to provide an overview of the structure and dynamics of land-use in this water-limited region. Copyright © 2006 John Wiley & Sons, Ltd.
The Carbon Balance of Two Riverine Wetlands Fifteen Years After Their Creation

Detailed carbon budgets from 2008 to 2010 were created for two 1-ha flow-through riverine wetlands created in 1994 adjacent to a third–order stream in central Ohio. Measurements were taken of dissolved non-purgeable organic carbon (NPOC), dissolved inorganic carbon (DIC), fine particulate organic carbon (FPOM), and coarse particulate organic carbon (CPOM). Methane emissions, soil sequestration, aquatic primary productivity, and macrophyte aboveground net primary productivity were also included in the carbon budget. The carbon budget successfully balanced inputs (1838 ± 41 g C m−2 year−1) and export/sequestration (1846 ± 59 g C m−2 year−1) with only a 0.5 % over estimation of export in relation to input; 12.8 % of the inflow was sequestered into the wetland soil. FPOM and CPOM concentrations and exports were positively correlated with hydrologic flow under most circumstances; NPOC and DIC concentrations were usually negatively or poorly correlated with hydrologic flow. In all seasons, except winter, the change of total carbon (NPOC, DIC, FPOM, and CPOM) concentration between inflow and outflow increased with increased hydrologic flow. Although carbon concentrations increased from inflow to outflow, the total surface water export of carbon is less than the inflow due to groundwater recharge from these perched wetlands.
Framing the future: embryonic stem cells, ethics and the emerging era of developmental biology.

Throughout the 20th century, advances in biology were accomplished largely through the study of biochemical parts apart from their place within the whole organism. This reductive and analytic approach, which has culminated in the sequencing of the human genome, has now led us back to the study of living beings. When applied to human biology, this inquiry re-opens the most fundamental questions concerning the moral meaning of developing life. The current conflict over ES (embryonic stem) cell research is just the first in a series of difficult controversies that will require us to clearly and precisely define the boundaries of humanity that we seek to defend. Through a careful consideration of the social, political, and scientific foundations of our current debate, we may discern the terms of a possible resolution that can sustain social consensus while opening avenues for scientific advance. Four such proposals were discussed in a May 2005 publication by the President's Council on Bioethics, entitled “Alternative Sources of Pluripotent Stem Cells.” One of these methods, altered nuclear transfer, proposes to use the technology of somatic cell nuclear transfer (SCNT), but with a pre-emptive genetic or epigenetic alteration that precludes the integrated and coordinated organization essential for natural embryogenesis. The moral and scientific dimensions of this proposal are discussed as a way forward for embryonic stem cell research as well as a frame for further studies in developmental biology.
Using particle simulations for parameter tuning of dynamical models of the magnetotail

WINDMI is a family of dynamical models of the magnetotail that use different closure schemes to derive truncated descriptions of the collisionless microscopic energy transfer processes occurring in the quasineutral layer. The six-dimensional systems are both Kirchhoffian and Hamiltonian in structure, ensuring that the power input from the solar wind is divided into physically realizable energy sub-components. Model parameters are defined analytically as volume integrals of physically identifiable quantities. Particle simulations are used to calculate the parameters for the various models, giving a direct comparison of the relative advantages of different closure schemes. A collisionless kinetic closure scheme that includes the heat flux gives better agreement with observations by allowing for a rapid non-adiabatic cooling of the central plasma sheet (CPS).
Optimal routing strategies for autonomous underwater vehicles in time-varying environment

This paper presents a mission system and the therein implemented algorithms for path planning in a time-varying environment based on graph methods. The basic task of the introduced path planning algorithms is to find a time-optimal path from a defined start position to a goal position with consideration of the time-varying ocean current for an autonomous underwater vehicle (AUV). Building on this, additional practice-oriented considerations in planning are discussed in this paper. Such points are the discussion of possible methods to accelerate the algorithms and the determination of the optimal departure time. The solutions and algorithms presented in this paper are focused on path planning requirements for the AUV "SLOCUM Glider". These algorithms are equally applicable to other AUVs or aerial mobile autonomous systems. Practice-oriented considerations in path planning for AUVs are discussed.The algorithms find a time optimal path in a time-varying ocean flow.The path planning algorithms are based on graph methods.It is important to define a large number of edges with different directions.Zermelo's formula leads to a pre-selection of promising successor vertices.
A Place for Ecopedagogy in Community Literacy

Educators focused on community literacy and public engagement have access to a unique critical platform where larger social issues that impact us both as a whole and on very personal levels are open to exploration. Being uniquely situated to have significant impact on community, literacy work in this area may require unique pedagogical strategies. Based on its comprehensive focus on sustainability, ecological literacy, sociopolitical factors that affect communities, and a multitude of other factors that underpin social injustice, ecopedagogy may be uniquely positioned to offer a more holistic view than other composition pedagogies such as place-based education and ecocomposition.
SEURAT: integrated rationale management

A completed software product is the end result of many decisions that must be made throughout the development lifecycle. Unfortunately, the rationale for these decisions is usually not captured and is therefore lost. The Software Using RATionale (SEURAT) system integrates with the Eclipse Interactive Development Environment to support rationale capture and use. In addition to presenting the rationale to the developer/maintainer as needed, SEURAT also supports requirements traceability and impact assessment.
A stochastic calculus for systems with memory

For a given stochastic process X, its segment Xt at time t represents the \slice" of each path of X over a xed time-interval [t r; t], where r is the length of the \memory" of the process. Segment processes are important in the study of stochastic systems with memory (stochastic functional dieren tial equations, SFDEs). The main objective of this paper is to study non-linear transforms of segment processes. Towards this end, we construct a stochastic integral with respect to the Brownian segment process. The dicult y in this construction is the fact that the stochastic integrator is innite dimensional and is not a (semi)martingale. We overcome this dicult y by employing Malliavin (anticipating) calculus techniques. The segment integral is interpreted as a Skorohod integral via a stochastic Fubini theorem. We then prove It^ o’s formula for the segment of a continuous Skorohod-type process and embed the segment calculus in the theory of anticipating calculus. Applications of the It^ o formula include the weak innitesimal generator for the solution segment of a stochastic system with memory, the associated Feynman-Kac formula and the Black-Scholes PDE for stock dynamics with memory.
Long-term management of patients with interspinal drug delivery systems

Abstract Interspinal drug delivery via pump for chronic pain and spasticity is only part of a more comprehensive patient management program for the long-term success of therapy. This therapy should not be relied upon solely, but rather used in conjunction with other rehabilitative modalities during long-term patient management. Physicians who manage these devices should be able to answer questions that arise from patients or other health-care providers regarding activity restrictions or other limitations imposed by this therapy. They should be able to recognize and treat side effects that arise from drugs used in the pump and complications related to the pump system. Physicians should also have a clear plan of action for patients whose symptoms are not well controlled. This review assesses the long-term management of patients who receive this therapy.
Closure pressure studies of the tapered ileal segment and reinforced ileocecal valve in continent urinary diversion

Objective. To evaluate the function of the continent segment, a tapered terminal ileum with reinforced ileocecal valve, utilized in continent colonic urinary reservoir. Methods. Closure pressure study of the continent mechanism was performed in 20 patients with the colonic reservoir empty and at maximum capacity. Results. Maximum pressure within the tapered ileum was recorded at the reinforced ileocecal valve and was recorded when the reservoir was full. Pressure ranged between 60 and 200 cm water (mean, 139.5 cm H2O). The pressure within the reinforced segment exceeded the pressure within the resevoir at all times. Conclusions. When properly reinforced, the ileocecal valve is able to maintain a closing pressure above that of the detubularized urinary reservoir, making it a reliable continent mechanism.
p21-activated Kinase (PAK1) Is Phosphorylated and Activated by 3-phosphoinositide-dependent kinase-1 (PDK1)

In this study, we show that phosphorylated 3-phosphoinositide-dependent kinase 1 (PDK1) phosphorylates p21-activated kinase 1 (PAK1) in the presence of sphingosine. We identify threonine 423, a conserved threonine in the activation loop of kinase subdomain VIII, as the PDK1 phosphorylation site on PAK1. Threonine 423 is a previously identified PAK1 autophosphorylation site that lies within a PAK consensus phosphorylation sequence. After pretreatment with phosphatases, autophosphorylation of PAK1 occurred at all major sites except threonine 423. A phosphothreonine 423-specific antibody detected phosphorylation of recombinant, catalytically inactive PAK1 after incubation with wild-type PAK1, indicating phosphorylation of threonine 423 occurs by an intermolecular mechanism. The biological significance of PDK1 phosphorylation of PAK1 at threonine 423 in vitro is supported by the observation that these two proteins interact in vivo and that PDK1-phosphorylated PAK1 has an increased activity toward substrate. An increase of phosphorylation of catalytically inactive PAK1 was observed in COS-7 cells expressing wild-type, but not catalytically inactive, PDK1 upon elevation of intracellular sphingosine levels. PDK1 phosphorylation of PAK1 was not blocked by pretreatment with wortmannin or when PDK1 was mutated to prevent phosphatidylinositol binding, indicating this process is independent of phosphatidylinositol 3-kinase activity. The data presented here provide evidence for a novel mechanism for PAK1 regulation and activation.
Properties of microsomal acyl coenzyme A reductase in mouse preputial glands.

Abstract Synthesis of long-chain fatty alcohols in preputial glands of mice is catalyzed by an NADPH-dependent acyl coenzyme A (CoA) reductase located in microsomal membranes; sensitivity to trypsin digestion indicates that the reductase is on the cytoplasmic side of the membrane. Results with pyrazole and phenobarbital demonstrate the reaction is not catalyzed by a nonspecific alcohol dehydrogenase or an aldehyde reductase. Acyl-CoA reductase activity is sensitive to sulfhydryl and serine reagent modification, is stimulated by bovine serum albumin, and produces an aldehyde intermediate. The activity is extremely detergent sensitive and cannot be restored even after removal of the detergents. Phospholipase C or asolectin treatment does not release the acyl-CoA reductase from microsomal membranes, but causes a significant decrease in the activity recovered in the membrane pellet. Glycerol does not solubilize the reductase activity, nor does 3.0 m NaCl; however, the combination of glycerol and 3.0 m NaCl did release about 50% of the acyl-CoA reductase from the microsomal pellet. Substrate concentration curves obtained in the presence or absence of bovine serum albumin show significant differences in enzyme activities. The reductase is sensitive to the concentration of palmitoyl-CoA and is progressively inhibited at levels beyond the critical micellar concentration of the substrate. The apparent Km for acyl-CoA reductase is 14 μ m ; however, the maximum velocity varies with the concentration of albumin used. Expression of enzyme activity in delipidated microsomes requires specific phospholipids, which suggests that in vivo regulation of acyl-CoA reductase activity could be achieved through modifications in membrane lipid composition.
Finding what's not there: a new approach to revealing neglected conditions in software

Neglected conditions are an important but difficult-to-find class of software defects. This paper presents a novel approach to revealing neglected conditions that integrates static program analysis and advanced data mining techniques to discover implicit conditional rules in a code base and to discover rule violations that indicate neglected conditions. The approach requires the user to indicate minimal constraints on the context of the rules to be sought, rather than specific rule templates. To permit this generality, rules are modeled as graph minors of program dependence graphs, and both frequent itemset mining and frequent subgraph mining algorithms are employed to identify candidate rules. We report the results of an empirical evaluation of the approach in which it was used to discover conditional rules and neglected conditions in ~25,000 lines of source code.
Teachers’ mathematical activity in inquiry-oriented instruction

Abstract This work investigates the relationship between teachers’ mathematical activity and the mathematical activity of their students. By analyzing the classroom video data of mathematicians implementing an inquiry-oriented abstract algebra curriculum I was able to identify a variety of ways in which teachers engaged in mathematical activity in response to the mathematical activity of their students. Further, my analysis considered the interactions between teachers’ mathematical activity and the mathematical activity of their students. This analysis suggests that teachers’ mathematical activity can play a significant role in supporting students’ mathematical development, in that it has the potential to both support students’ mathematical activity and influence the mathematical discourse of the classroom community.
Crosstalk and considerations in endocrine disruptor research

The presence of endocrine disrupting chemicals in the environment has prompted action on several fronts to assess the potential health risks of these compounds. To fully understand the mechanisms behind the observed endocrine disruption, crosstalk and other factors should be considered. In this article we will discuss how crosstalk modulates estrogen action in several common assays and how this and other considerations appear to have been overlooked. In addition, a paradigm shift from theoretical linear response pathways to interaction maps should aid in the understanding and analysis of endocrine disruption.
Computed Neutron Tomography from Real-Time Radiographic Images

A real-time neutron radiography facility was constructed including the capability of neutron tomography. A tomography algorithm, using the convolution method, was programmed on an Intellect 100 Image Processing System. The method produced results near the theoretical resolution limits for a given number of projections. A tomographic resolution of at least 1.3 mm was demonstrated using 200 projections. Computer running time for the convolution method was found to be about 30 seconds for each projection used.
Gram-positive Organisms and Sepsis

In recent years, the importance of gram-negative organisms in the genesis of sepsis has been emphasized. However, this emphasis may no longer be correct; recent studies show an increasing incidence of gram-positive sources of sepsis, and it is possible that these cases may predominate in the coming years. This increase results from more than just a greater prevalence of infection—it appears that gram-positive organisms may also be more virulent in fomenting the disease, as can be evidenced by the emergence of streptococcal toxic shock syndrome and the resurgence of acute rheumatic fever. This may result from the ability of gram-positive organisms to produce more inflammation-causing cell wall constituents, as well as unbound exotoxins. Despite the recent emphasis on gram-negative causes, sepsis resulting from gram-positive sources is increasingly common. Research on these causes of sepsis should be encouraged. (Arch Intern Med. 1994;154:26-34)
Applications of Microfluidics for Neuronal Studies

Microfabrication processes have changed the technology used in consumer goods, and have now advanced into applications in biology. Microfluidic platforms are microfabricated tools that are gaining popularity for studies of molecular and cellular biology. These platforms can allow precise control of the environment surrounding individual cells and they have been used to study physiologic and pharmacologic responses at the single-cell level. This article reviews microfluidic technology with emphasis on advances that could apply to the study of the nervous system, including architecture for isolation of axons, integrated electrophysiology, patterned physical and chemical substrate cues, and devices for the precisely controlled delivery of possible therapeutic agents such as trophic factors and drugs. The potential of these chips for the study of neurological diseases is also discussed.
Social capital and crime in New York City's low‐income housing

This article presents evidence that components of social capital can play a prospective role in preventing crime in low-income housing. It develops a conceptual approach to crime prevention involving social capital, alternative forms of ownership, and environmental design considerations. The study compares five programs that house New York City’s poorest, mostly minority residents. The effectiveness of social capital in preventing crime is assessed using data from surveys of 487 buildings in Brooklyn, NY, and crime data from the New York City Police Department. Results of the analysis indicate that three components of social capital—basic participation in tenant associations, tenant prosocial norms, and a building’s formal organization—were all related to reducing various types of crime in the buildings under study 6 to 12 months after social capital was measured. The effectiveness of social capital was related to alternative ownership structures, building characteristics, and housing policy.
Infections of the central nervous system in transplant recipients.

Central nervous system (CNS) infections, accounting for 4-29% of CNS lesions in transplant recipients, are a significant post-transplant complication. Focal CNS infectious lesions or brain abscesses have been documented in 0.36-1% of the transplant recipients. Mycelial fungi, particularly Aspergillus, are by far the most frequent etiologies of post-transplant brain abscesses. Bacteria, with the exception of Nocardia, are rarely associated with brain abscesses in transplant recipients. Time of onset and concurrent extraneural lesions have implications relevant towards invasive diagnostic procedures in transplant recipients with brain abscesses. Meningoencephalitis in transplant recipients is predominantly due to viruses, e.g., herpesviruses, and less frequently due to Listeria monocytogenes, Toxoplasma gondii, and Cryptococcus. Despite a wide, and at times perplexing array of opportunistic pathogens that can cause CNS infections, the temporal association of the infection with the time elapsed since transplantation, risk factors, clinical manifestations, and neuroimaging characteristics of the lesion can allow a reasoned and rational approach towards the recognition, diagnosis, and appropriate management of CNS infections in transplant recipients.