cssi/SciSciGPT-SciSciNet huggingface dataset:
Perioperative management of the pediatric patient with traumatic brain injury.

Summary TBI and its sequelae remain a major healthcare issue throughout the world. With an improved understanding of the pathophysiology of TBI, refinements of monitoring technology, and ongoing research to determine optimal care, the prognosis of TBI continues to improve. In 2003, the Society of Critical Care Medicine published guidelines for the acute management of severe TBI in infants, children, and adolescents. As pediatric anesthesiologists are frequently involved in the perioperative management of such patients including their stabilization in the emergency department, familiarity with these guidelines is necessary to limit preventable secondary damage related to physiologic disturbances. This manuscript reviews the current evidence-based medicine regarding the care of pediatric patients with TBI as it relates to the perioperative care of such patients. The issues reviewed include those related to initial stabilization, airway management, intraoperative mechanical ventilation, hemodynamic support, administration of blood and blood products, positioning, and choice of anesthetic technique. The literature is reviewed regarding fluid management, glucose control, hyperosmolar therapy, therapeutic hypothermia, and corticosteroids. Whenever possible, management recommendations are provided.
Nanostructured Catalysts: Controlling Single‐Site Composition

Developing well-understood methodologies for the preparation of single-site catalysts has long been a goal in catalysis science. Newly emerging strategies for preparing and functionalizing nanostructured materials open the door to a number of new approaches that address this goal. General, structural, and chemical definitions of nanostructured, single-site catalysts are presented, and the challenges associated with meeting these requirements are discussed. Selected examples of nanostructuring strategies that lead to well-defined single-site catalysts are described. Keywords: nanostructured solid; single-site catalyst; heterogeneous catalysis; porous solids; high surface area materials; hierarchical nanostructuring; zeolite; nanoscience
Potential Misuse of Avian Density as a Conservation Metric

Effective conservation metrics are needed to evaluate the success of management in a rapidly changing world. Reproductive rates and densities of breeding birds (as a surrogate for reproductive rate) have been used to indicate the quality of avian breeding habitat, but the underlying assumptions of these metrics rarely have been examined. When birds are attracted to breeding areas in part by the presence of conspecifics and when breeding in groups influences predation rates, the effectiveness of density and reproductive rate as indicators of habitat quality is reduced. It is beneficial to clearly distinguish between individual- and population-level processes when evaluating habitat quality. We use the term reproductive rate to refer to both levels and further distinguish among levels by using the terms per capita fecundity (number of female offspring per female per year, individual level) and population growth rate (the product of density and per capita fecundity, population level). We predicted how density and reproductive rate interact over time under density-independent and density-dependent scenarios, assuming the ideal free distribution model of how birds settle in breeding habitats. We predicted population density of small populations would be correlated positively with both per capita fecundity and population growth rate due to the Allee effect. For populations in the density-dependent growth phase, we predicted no relation between density and per capita fecundity (because individuals in all patches will equilibrate to the same success rate) and a positive relation between density and population growth rate. Several ecological theories collectively suggest that positive correlations between density and per capita fecundity would be difficult to detect. We constructed a decision tree to guide interpretation of positive, neutral, nonlinear, and negative relations between density and reproductive rates at individual and population levels.
The Multi-lumen Catheter: Proposed Guidelines for Its Use

Infusion therapy for the administration of blood products, fluids, and parenteral nutrition are essential parts of medical practice. The risks associated with such therapy are well documented but frequently unappreciated. Intravascular infusions are the single most common cause of nosocomial bacteremia.’ Many studies have focused on the epidemiology, microbiology, and pathophysiology of these infections. In recent years, several companies have introduced a multi-lumen intravenous catheter that is placed through the subclavian or internal jugular vein. Unlike a multi-lumen pulmonary artery catheter, the multi-lumen intravenous catheter is designed solely for intravenous access. The first of these catheters was introduced in 1983, and it was soon followed by several others. These catheters have been designed to allow multiple infusions to be given simultaneously. In addition, one of the ports can be used for venous access. The advantages of these catheters are obvious. The clinician is given three ports for use instead of one. The catheter may be used to simplify infusion therapy. In some instances, cut-downs and other invasive procedures (Hickmans, Broviacs, Mediports) may be avoided. It is not surprising that the use of these catheters has grown. In many institutions, multi-lumen catheters account for a majority of all centrally placed catheters, and in some intensive care units, they are used almost exclusively. The enormous growth of the use of the multi-lumen catheter has occurred despite minimal data regarding risk, cost, and the proper procedures needed for its care.
Radiocarbon chronology of Black Sea sediments

Accelerator Mass Spectrometer (AMS) radiocarbon analyses have been made on 102 samples from 12 sediment cores and 23 samples from two water column profiles. These materials, collected during the first leg of the 1988 joint U.S.-Turkish Black Sea Expedition, provide the most comprehensive radiocarbon chronology of Black Sea sediments yet attempted. Radiocarbon analyses from carefully collected box cores and a mollusc shell collected live in 1931 suggest the prebomb surface waters had a Δ14C value of −55% (460 years) and that the maximum detrital correction for radiocarbon ages of Unit I sediments is 580 years for the organic carbon and 260 years for the carbonate fractions. Evidence does not support the 1430–2000 years pre-bomb surface water and/or detrital corrections argued for in past studies. The best estimates for the age of the beginning of the final invasion of the coccolithophore Emiliania huxleyi (Unit 12 boundary of Ross and Degens, 1974, The Black Sea—geology, chemistry and biology, pp. 183–199) and the age of the first invasion of E. huxeleyi (Unit I/II boundary of Hayet al., 1991, Deep-Sea Research, 38, S1211–S1235) are 1635 ± 60 and 2720 ± 160 years BP, respectively. Sapropel formation began at approximately 7540 ± 130 years BP at all depths in the basin, a pattern in disagreement with those predicted by existing time-evolution models of sapropel formation for this basin. Our data suggest that the oxic-anoxic interface has remained relatively stable throughout the Holocene, is controlled largely by the physical oceanography of the basin, and has not evolved as assumed by previous workers.
Discrete groups with large exponents in cohomology

Let Γ be a discrete group of finite virtual cohomological dimension. The Farrell cohomology of Γ,Ĥ∗(Γ,Z), depends on the finite subgroups of Γ, in a manner which is not yet well-understood. In this paper we produce examples of groups with nontrivial finite subgroups of order at most p (a prime) but with arbitrarily high p-torsion in their Farrell cohomology. We describe a method for constructing discrete groups with large exponents starting from a finite group acting freely on an aspherical complex.
Integration of Aeroservoelastic Properties into the NASA Dryden F/A-18 Simulator Using Flight Data from the Active Aeroelastic Wing Program

Aircraft structures have varying stiffness levels making them flexible. Consequently, this elastic property becomes increasingly important at high speeds affecting the flight dynamics of the aircraft. In high speed aircraft such as the F/A-18, elastic structural properties must be accounted for to ensure confidence in predicted flight dynamics in order to avoid adverse aeroelastic phenomena throughout flight. Data from the F/A-18 Active Aeroelastic Wing (AAW) program was used to create aeroservoelastic (ASE) models at varying flight conditions. This paper focuses on the integration process of these models into the NASA Dryden F/A-18 digital simulator. The ASE models were discretized and added in parallel with the traditional rigid body response model to ensure minimal disruption to the existing operating framework of the digital simulator. An interpolation scheme was used to construct ASE models within the known flight condition models. Data was processed through the state space ASE models to compute the elastic effects during flight. Total flight dynamics from the simulation were analyzed and showed expected behavior for the combined elastic and rigid body components in flight. The model integration process will be discussed along with an overview of the results of the combined rigid body and elastic flight dynamics output from the simulator.
IS ENDOSCOPIC DECOMPRESSION OF THE NEONATAL EXTRAVESICAL UPPER POLE URETEROCELE NECESSARY FOR PREVENTION OF URINARY TRACT INFECTIONS OR BLADDER NECK OBSTRUCTION

Purpose: It has been hypothesized that endoscopic decompression of the duplex extravesical ureterocele is necessary to prevent the complications of urinary tract infections and progressive hydronephrosis. This study was performed to test this premise.Materials and Methods: Infants younger than 2 weeks with an extravesical ureterocele associated with a duplex upper pole moiety were assigned to immediate endoscopic puncture of the ureterocele followed by antibiotic prophylaxis or antibiotic prophylaxis with plans for delayed surgical intervention. Radiographic studies and catheterized urine cultures were obtained at ages 3 and 6 months and for fever greater than 38.5C. All patients included in this study were followed through 6 months of life.Results: Of the patients 32 underwent endoscopic puncture of the ureterocele. Median patient age at endoscopy was 5 days (range 3 to 13). During the first 6 months of life complications developed in 4 (12%), including febrile urinary tract infections in 3 (9%) and with...
Heaviside's direct operational calculus

OPERATIONAL CALCULUS is a very powerful tool for solving the differential equations of engineering. This article discusses some of the basic principles of Heaviside's direct operational calculus and how they can be applied to the solution of engineering problems. No attempt will be made to prove the various expressions that are to be used or to cover completely all the points of interest. The necessary justifications can be derived from the material to be presented in subsequent articles of this series.
Solution structure and dynamic analysis of chicken MBD2 methyl binding domain bound to a target-methylated DNA sequence

The epigenetic code of DNA methylation is interpreted chiefly by methyl cytosine binding domain (MBD) proteins which in turn recruit multiprotein co-repressor complexes. We previously isolated one such complex, MBD2-NuRD, from primary erythroid cells and have shown it contributes to embryonic/fetal β-type globin gene silencing during development. This complex has been implicated in silencing tumor suppressor genes in a variety of human tumor cell types. Here we present structural details of chicken MBD2 bound to a methylated DNA sequence from the ρ-globin promoter to which it binds in vivo and mediates developmental transcriptional silencing in normal erythroid cells. While previous studies have failed to show sequence specificity for MBD2 outside of the symmetric mCpG, we find that this domain binds in a single orientation on the ρ-globin target DNA sequence. Further, we show that the orientation and affinity depends on guanine immediately following the mCpG dinucleotide. Dynamic analyses show that DNA binding stabilizes the central β-sheet, while the N- and C-terminal regions of the protein maintain mobility. Taken together, these data lead to a model in which DNA binding stabilizes the MBD2 structure and that binding orientation and affinity is influenced by the DNA sequence surrounding the central mCpG.
Application of planetary analog mechanical properties to subsurface geological investigations

Abstract Investigations of the mechanical properties of planetary analog materials are of great importance to improve future mission success and to enhance our understanding of the history and evolution of planetary surfaces and subsurfaces. Determining the stratigraphy of the subsurface using drills and penetrometers implies knowing the mechanical properties of the regolith. Therefore, we investigated the mechanical properties of Martian regolith analogs (JSC Mars-1 and an unaltered basaltic soil from Mojave desert). Penetration force is dependent on the bearing capacity factor (Nq) and the angle of internal friction which is found to be function of the level of compaction and increases with relative density. The bearing capacity factor (Nq) showed an exponential trend with the angle of internal friction. For Mojave soil, (Nq) increased from 64 to 338 with φ increasing from 32 to 41.3° while (Nq) increased from 161 to 3347 with φ increasing from 39.4 to 54.7° for JSC Mars-1. Based on estimation of the bearing capacity factor and the angle of internal friction, we predicted the force of penetration under the Martian gravity using a 1.2 cm diameter penetrometer. Under a bulk density of 1240 and 1500 kg m−3 in JSC Mars-1 and Mojave soil, 460 and 200 N is the estimated force to reach a depth of about 20 cm deep. Based on this investigation, distinguishing between different regolith layers on the subsurface of Mars is possible and observable using penetration force.
Designing a high-performance clustered NAS: a case study with pNFS over RDMA on InfiniBand

Large scale scientific and commercial applications consume and producepetabytes of data. This data needs to be safely stored, cataloged and reproducedwith high-performance. The current generation of single headed NAS(Network Attached Storage) based systems such as NFS is not able to provide anacceptable level of performance to these types of demanding applications. ClusteredNAS have evolved to meet the storage demands of these demanding applications.However, the performance of these Clustered NAS solutions is limited bythe communication protocol being used, usually TCP/IP. In this paper, we propose,design and evaluate a clustered NAS; pNFS over RDMA on InfiniBand. Our resultsshow that for a sequential workload on 8 data servers, the pNFS over RDMAdesign can achieve a peak aggregate Read throughput of up to 5,029 MB/s, a maximumimprovement of 188% over the TCP/IP transport and a Write throughput of1,872 MB/s; a maximum improvement of 150% over the corresponding TCP/IPtransport throughput. Evaluations with other type of workloads and traces showan improvement in performance of up to 27%. Finally, our design of pNFS overRDMA improves the performance of BTIO relative to the Lustre file system.
Fusion ignition of microfission explosions

WINTERBERG1 proposed that microexplosions could be caused in very small amounts of fissionable materials such as 233U, 235U, and 239Pu (see also refs 2 and 3). A small critical mass could be created by imploding the fissionable material until it was 200–300 times its normal density. This could be achieved using a high energy, properly shaped laser pulse (of about 1 ns duration). For a chain reaction to begin in the assembled critical mass, however, neutrons must be present to initiate the fission process. For a critical mass of uranium, of 0.34 g, and a hydrodynamic disassembly time of 10−9s, as proposed by Winterberg1, conventional neutron sources will not be adequate to initiate a chain reaction. Initiation of the fission process using neutrons produced from the fusion of a deuterium–tritium (D–T) mixture placed in the core of the fissionable material seems feasible and offers several distinct advantages over conventional neutron sources.
Neuroendocrine carcinomas: Role of immunocytochemistry and electron microscopy

Neuroendocrine tumors occur in many sites of the body and can present significant diagnostic problems when poorly differentiated. To identify a tumor as neuroendocrine, pathologists commonly use either immunocytochemistry or electron microscopy. In this report, the various immunocytochemical reagents are reviewed along with the ultrastructural features of neuroendocrine tumors. Site-specific variations in neuroendocrine tumors are discussed. A cost-effectiveness evaluation was performed on tumors from one laboratory which showed that electron microscopy was a less expensive diagnostic modality if more than three antibodies were necessary to arrive at the correct pathological diagnosis.
Entropy defect and information for two quantum states

An explicit formula is obtained for the entropy defect and the (maximum) information for an ensemble of two pure quantum states; an optimal basis is found, that is, an optimal measurement procedure which enables one to obtain the maximum information. Some results are also presented for the case of two mixed states, described by second-order density matrices (for example, spin polarization matrices). It is shown that in the case of two states the optimal measurement is a direct von Neumann measurement performed in the subspace of the two states.
Lacerta OB1 Revisited

This investigation utilizes precise uvbyβ photometry and the recently recalculated Hipparcos data to provide an improved homogeneous distance scale for the apparent groups of young stars in Lacerta. All existing uvbyβ photometry for stars earlier than A0-type in a 20° × 20° field centered at l = 100°, b = -15° is collated and the individual stellar distances and color excesses are obtained. The association Lac OB1 is reliably identified as a very compact young group of 12 bright stars at an average distance of 520 ± 20(s.e.) pc. The available radial velocity and proper motion measurements strongly support the impression that the group is real. The stars in the northeast part of Lacerta seem not to represent a physical group, but rather a layer of field stars spread between 140 and 400 pc and extending farther than that toward l ~ 104°. An estimate of 678 ± 50(s.e.) pc of the distance to the open cluster NGC 7243 is obtained based on the brightest cluster members. The calculated distances are based on a well-tested procedure, and thus represent a clarification over the range of distance existing in the literature for the bright stars in the Lacerta field. Although a better agreement is now evident between the photometric distances and the recalculated Hipparcos parallaxes in comparison to the original Hipparcos data, discrepancies still exist for this particular field.
Research on innovation in organizations: Distinguishing innovation-generating from innovation-adopting organizations

Research on innovation in organizations has generally examined the differences in the characteristics of innovative and non-innovative organizations, an endeavor that has often produced inconsistent results. In this paper, we propose that future research may resolve those inconsistencies by incorporating in the theory the differences between organizations that mostly generate innovations and those that mostly adopt innovations. We refer to the former, which are primarily producers or suppliers of innovation, as innovation-generating organizations, and to the latter, which are preponderantly users of innovations produced by innovation-generating organizations, as innovation-adopting organizations. Building on the notion that the processes of generating and adopting innovation are distinct phenomena that are facilitated by different organizational conditions, we discuss how the distinction between innovation-generating and innovation-adopting organizations would contribute to clarifying several inconsistent research findings, such as the relationship between innovation and size, the role of innovation radicalness, and the selection of appropriate measures of innovation.
Carbon Nanotube–Poly(lactide- co -glycolide) Composite Scaffolds for Bone Tissue Engineering Applications

Despite their indisputable clinical value, current tissue engineering strategies face major challenges in recapitulating the natural nano-structural and morphological features of native bone. The aim of this study is to take a step forward by developing a porous scaffold with appropriate mechanical strength and controllable surface roughness for bone repair. This was accomplished by homogenous dispersion of carbon nanotubes (CNTs) in a poly(lactide-co-glycolide) (PLGA) solution followed by a solvent casting/particulate leaching scaffold fabrication. Our results demonstrated that CNT/PLGA composite scaffolds possessed a significantly higher mechanical strength as compared to PLGA scaffolds. The incorporation of CNTs led to an enhanced surface roughness and resulted in an increase in the attachment and proliferation of MC3T3-E1 osteoblasts. Most interestingly, the in vitro osteogenesis studies demonstrated a significantly higher rate of differentiation on CNT/PLGA scaffolds compared to the control PLGA group. These results all together demonstrate the potential of CNT/PLGA scaffolds for bone tissue engineering as they possess the combined effects of mechanical strength and osteogenicity.
Mesoscale and Convective–Scale Downdrafts as Distinct Components of Squall-Line Structure

Abstract This paper describes the two different kinds of downdraft air frequently observed to the rear of some squall lines at low levels. The primary data source is measurements taken during aircraft penetrations of certain low-latitude squall lines; they are supplemented by satellite data, radar data, surface meteorological data, and soundings ahead of and behind the squall lines. A shallow layer of cool, near-saturated air occupies the lowest few hundred meters and is separated by a marked stable layer from a deep layer of highly unsaturated air. The lowest layer is hypothesized to be the product of convective-scale saturated downdrafts, and the drier air is shown to be the result of mesoscale unsaturated downdrafts as described by Zipser (1969). Over a warm ocean, there is a large latent and sensible heat flux from the surface into the lowest layer, which rapidly becomes a new mixed layer and incorporates the drier air from above by entrainment. Mesoscale sinking in the post-squall region is shown to ...
Targeted treatment of head and neck squamous-cell carcinoma: potential of lapatinib

Squamous-cell cancer of the head and neck is a heterogeneous malignancy with treatment predicated on a multimodality therapy involving surgery, chemotherapy, and radiation. However, this approach results in durable responses in only a subset of patients, and is associated with significant toxicity. In advanced disease, multi-agent platinum-based chemotherapy produces only modest improvements in survival. Increased insight into tumor biology has demonstrated several critical oncogenic pathways offering prospects for targeted therapy that may improve upon the existing treatment strategies. The epidermal growth factor receptor is one such target, and directed therapy with the monoclonal antibody cetuximab has been extensively studied. Lapatinib is an oral agent that targets multiple transmembrane receptors within the epidermal growth factor receptor family, and offers a promising new approach to treatment. This paper reviews the rationale for and clinical activity of lapatinib in squamous-cell cancer of the head and neck.
The Digital Individual and the Private Realm

Geographic information systems and the technological family associated with them—global positioning systems, geodemographics, and remote surveillance systems—raise important questions with respect to the issue of privacy. Of most immediate import, the systems store and represent data in ways that render ineffective the most popular safeguards against privacy abuse. But the systems are associated with more fundamental changes in the right to privacy and even, some would say, with challenges to the possibility of privacy itself. They make reasonable and acceptable the view that technological change is inevitable and autonomous, and therefore, too, are the development of increasingly comprehensive dossiers on individuals and households and the use of increasingly powerful means for the technological enhancements of vision. And their use in the creation of data profiles supports a wide-ranging reconceptualization of community, place, and individual. Nonetheless, in the ways they create and use digital profile...
A Remodeled Protein Arginine Methyltransferase 1 (PRMT1) Generates Symmetric Dimethylarginine

Protein arginine methylation is emerging as a significant post-translational modification involved in various cell processes and human diseases. As the major arginine methylation enzyme, protein arginine methyltransferase 1 (PRMT1) strictly generates monomethylarginine and asymmetric dimethylarginine (ADMA), but not symmetric dimethylarginine (SDMA). The two types of dimethylarginines can lead to distinct biological outputs, as highlighted in the PRMT-dependent epigenetic control of transcription. However, it remains unclear how PRMT1 product specificity is regulated. We discovered that a single amino acid mutation (Met-48 to Phe) in the PRMT1 active site enables PRMT1 to generate both ADMA and SDMA. Due to the limited amount of SDMA formed, we carried out quantum mechanical calculations to determine the free energies of activation of ADMA and SDMA synthesis. Our results indicate that the higher energy barrier of SDMA formation (ΔΔG‡ = 3.2 kcal/mol as compared with ADMA) may explain the small amount of SDMA generated by M48F-PRMT1. Our study reveals unique energetic challenges for SDMA-forming methyltransferases and highlights the exquisite control of product formation by active site residues in the PRMTs.
Moving Beyond Culturalism and Formalism: Islam, Women, and Political Unrest in the Middle East

ABSTRACTScenes of political unrest throughout the Middle East are often coupled with media reports and public debates in the United States that have a recurring theme: the relationship between women and Islam. After discussing the culturalist accounts that portray women as being in grave danger from Islam and in need of Western protection and supervision, this contribution examines an emerging trend in political science developed under the influence of the formalism of neoclassical economics. The study argues that despite ostensibly universal assumptions about human behavior and alleged objectivity, the theoretical foundations of neoclassical economics and its methodological formalism fall short in providing an alternative to culturalism, and, instead, reinforce the misperceptions and misunderstandings about the region.
Stimulation of frog gustatory units by calcium

Abstract 1. 1. Integrated recordings from the whole frog glossopharyngeal nerve in response to CaCl2 solutions applied to the tongue often show saturation, or limiting responses, at high stimulus concentrations. This behavior suggests the operation of a binding mechanism. 2. 2. However, single axons of the glossopharyngeal nerve show a wide variety of stimulus-response curves, most of which cannot be described by simple binding theory. 3. 3. The mechanism of gustatory stimulation by CaCl2 solutions depends on free Ca2+ ions, and not on chloride, water or undissociated CaCl2. 4. 4. Presoaking the tongue in EDTA before testing produces a great increase in the response to CaCl2. 5. 5. Calcium chloride responses are strongly inhibited by the presence of NaCl or KCl. The inhibition does not depend on chloride in the stimulating solution and is apparently a cationic effect.
Statistical Analysis of Uncertainties in Deterministic Computational Modeling – Application to Composite Process Resin Infusion Flow Model

Deterministic physics-based flow modeling provides an effective way to simulate and understand the resin flow infusion process in liquid composite molding processes and its variants. These are effective to provide optimal injection time and locations prior to gelation for given process parameters of resin viscosity and preform permeability. However, there could be significant variations in these two parameters during actual manufacturing. This paper presents simulation-based statistical analysis of uncertainties of these process parameters involved in the resin flow infusion. Two key process parameters, viscosity and permeability, and their statistical variations are examined individually and subsequently in combination for their impact on the associated injection time. Values from statistical probability distribution of the process parameters were employed to find the solution space for this engineering application through deterministic physics-based process flow modeling simulations. A bivariate confide...
Relationship between ego-involvement instructions and various motivation and performance measures.

Summary.-The effects of ego-involvement instructions (EIs) were investigated in two studies. In Exp. I, EIs had no significant effect on a response measure of ego-involvement (EIn) nor on RT and paired-associate verbal learning. Aoxiery, as measured by the MAS, and n achievement, as measured by the EPPS, did not significantly correlate with any of the measures, but a significant effect was found for EIn when anxiety and EIs were analyzed in a 2 X 2 design. When more extreme EIs were used in Exp. 11, EIs had a significant effect on EIR and verbal learning: higher EIR ratings were obtained for high than low EIB and, for Ss receiving a low response-competiuon list, fewer errors were made under high than low EIs.
LIMITING STATE OF AN ORTHOTROPIC PLATE WEAKENED BY A PERIODIC SYSTEM OF COLLINEAR CRACKS

On the basis of a modified δc-model of cracks, we study the limiting state of an orthotropic plate made of a material satisfying the general strength condition and weakened by a system of collinear cracks. The relations for the determination of major parameters of the model of cracks (the size of process zones, stresses in these zones, and the crack-tip opening displacements) are deduced. The mechanism of fracture of the plate containing a periodic system of collinear cracks is investigated. The influence of the degree of anisotropy and geometric parameters of the problem on the formation of the process zones and limiting state of the plate is revealed. The region of safe loading of an orthotropic viscoelastic plate with cracks is determined. The influence of the rheological parameters of the material on the region of safe loading is analyzed. Numerous modern works in the field of fracture mechanics are devoted to the development of new approaches to the investigation of fracture processes in various materials (metals, polymers, composites, rocks, etc.) under the action of external loads of various types [1–5]. The extensive application of elements made of anisotropic materials explains the necessity of investigation of their behavior under loads close to critical [6 – 8]. In [9], on the basis of a modified Leonov – Panasyuk – Dugdale model, the solutions of the problems of fracture were constructed for orthotropic plates of elastic, elastoplastic, and viscoelastic materials weakened by rectilinear cracks. In a similar statement, the solution of the problem of fracture of an orthotropic plate weakened by a periodic system of collinear cracks was obtained in [10]. In what follows, we investigate the limiting state of an orthotropic plate of viscoelastic material weakened by a periodic system of collinear cracks.
For the love of the land: How emotions motivate volunteerism in ecological restoration

Abstract This article describes, analyzes and synthesizes the emotions expressed by volunteers in a community-based ecological restoration effort in the western United States. We present a qualitative case study, the Partners for Native Plants (PNP) project, with the hopes of better understanding what emotions, flanked by values, motivations and goals, lead to involvement in environmental initiatives. Emotions play a dual role as both the outcome of event appraisal, examining whether one has achieved or not achieved a desired state, and also to function as motivators to work toward goal achievement. We examined two broad categories of emotions expressed by PNP participants. We examined those expressed in response to or as a motivation for the achievement of desired nature-based goals (pleasure-related) as well as emotions that are expressed in response to avoiding an undesired outcome or as a motivation to avoid goal impairment (responsibility-related), namely environmental degradation. Behaviors to protect nature are not based solely on cognitive decisions, but are motivated by a wide variety of emotions including self-blame, indignation, and affinity to nature. This information may be useful in understanding how to appeal to emotions and engage urban people as volunteers in hands-on environmental restoration.
Homotopy invariants of repeller-attractor pairs, II. Continuation of R-A pairs

On considere une famille continue a 1 parametre de flots dans le plan parametrise par λ∈[0,1]. On etablit un cadre qui rend precise la notion de famille continue de paires de repulseur-attracteurs. On montre qu'il y a des equivalences naturelles entre les suites d'indices de 2 paires R-A le long d'un parcours de paires R-A
Radiotherapy Combined with Gemcitabine and Oxaliplatin in Pancreatic Cancer Cells

Clinical evidence suggests that gemcitabine (Gem) plus oxaliplatin (Ox) is superior to gemcitabine alone in advanced pancreatic carcinoma. The addition of radiation to gemcitabine improves response and is a standard treatment for locally advanced disease. We investigated the effect of oxaliplatin on gemcitabine-based chemoradiation by determining whether gemcitabine and oxaliplatin produced synergistic cytotoxicity using median effect analysis and radiosensitization using clonogenic survival assays. We analyzed the effects of gemcitabine and oxaliplatin on cell cycle distribution by DNA content and on radiation-induced DNA damage repair by phosphorylated H2AX (γ-H2AX). Gemcitabine and oxaliplatin produced schedule-dependent synergistic cytotoxicity in BxPC-3 and Panc-1 cells (combination indices: 0.76 ± 0.05, 0.61 ± 0.11). In BxPC-3 cells, oxaliplatin did not affect gemcitabine-mediated radiosensitization (Gem 1.99 ± 0.27; Gem + Ox 2.38 ± 0.30). In Panc-1 cells, oxaliplatin significantly enhanced gemcitabine-mediated radiosensitization (Gem 1.31 ± 0.05; Gem + Ox 2.90 ± 0.31). Radiosensitization by gemcitabine was accompanied by early S-phase arrest and induction/persistence of γ-H2AX protein, which were unaltered by oxaliplatin. Addition of oxaliplatin to gemcitabine produces radiosensitization equal to or greater than gemcitabine alone, supporting our clinical investigation of oxaliplatin with gemcitabine-radiation in pancreatic cancer aimed at improving systemic disease control while maintaining local tumor radiosensitization.
Improved RNA-Seq Partitions in Linear Models for Isoform Quantification

Here, we present an extension of our is form quantification method that accommodates paired end RNA Sequencing data. We explore several alternate methods of partitioning read count data in order to better exploit the available fragment size distribution, and to reduce the variance in the resulting estimates. In many cases, this significantly improves the accuracy of our approach.
Fluorescence and chemical modification of tryptophan as probes of structure of GTP:AMP phosphotransferase from beef heart mitochondria.

Selective modification of the two Trp residues of GTP:AMP phosphotransferase from beef heart mitochondria (Mr 26000; MgGTP + AMP ⇆ MgGDP + ADP) has been attained by treatment of the enzyme with N-bromosuccinimide at pH 4.0. Almost complete loss of activity is observed when one Trp is oxidized. Fluorescence emission spectra (λexc 295 nm) were recorded over the pH range 1.9–12.2. Quenching constants, K, with acrylamide were 4.9, 3.4, 3.1, 2.4, 9.2 and 9.4 M−1 at respective pH values of 11.1, 7.5, 5.5, 4.0, 1.9 and 7.5 with 6 M guanidine/HCl. Over the pH range 8.0–5.5 the fluorescence peak has a constant height with maximum at 333–334 nm, which can be segregated by acrylamide quenching into a peak with maximum at 338 nm and another with maximum at 330 nm. Dropping the pH from 5.5 to 4.0 results in the fluorescence at 338 nm decreasing to 335 nm (indicative of less exposure of the Trp) while that at 330 nm remains constant. Thus the limitation of reactivity to N-bromosuccinimide to pH 4.0 or lower cannot be accounted for by increased exposure of the Trp residues but rather must be explained by a change in the microenvironment of each Trp. As shown by K values above, at pH 2.0 Trp residues are exposed to the solvent, as in the case of treatment with 6 M guanidine hydrochloride. In raising the pH from 8.0 to 12.0 a number of changes occur: (a) the λmax of emission shifts from 333–334 nm to 343 nm; (b) residue(s) become(s) more available to acrylamide quenching; (c) fluorescence decreases and enzymatic activity increases, both with a midpoint at about 10.6; (d) absorption difference spectra show a maximum at 295 nm typical of Tyr ionization. These data are consistent with conformational change as the pH becomes more alkaline making the Trp residue(s) more exposed to the solvent and/or to non-radiative energy transfer to tyrosinate.
Accuracy of laplacian edge detectors

The sources of error for the edge finding technique proposed by Marr and Hildreth (D. Marr and T. Poggio, Proc. R. Soc. London Ser. B 204 , 1979, 301–328; D. Marr and E. Hildreth, Proc. R. Soc. London Ser. B. 207 , 1980, 187–217) are identified, and the magnitudes of the errors are estimated, based on idealized models of the most common error producing situations. Errors are shown to be small for linear illuminations, as well as for nonlinear illuminations with a second derivative less than a critical value. Nonlinear illuminations are shown to lead to spurious contours under some conditions, and some fast techniques for discarding such contours are suggested.
The genetics of inherited sideroblastic anemias

The sideroblastic anemias are a heterogeneous group of acquired and inherited bone marrow disorders defined by the presence of pathologic iron deposits in erythroblast mitochondria. While the pathogenesis of almost all cases of acquired sideroblastic anemia is unknown, the molecular genetic basis for several of the inherited forms have now been described. Initially, mutations in ALAS2 in X-linked sideroblastic anemia (XLSA) focused attention on the heme biosynthetic pathway as a primary cause of sideroblastic anemia. However, the subsequent description of the genes involved in XLSA with ataxia, thiamine-responsive megaloblastic anemia, and Pearson marrow-pancreas syndrome have implicated other pathways, including mitochondrial oxidative phosphorylation, thiamine metabolism, and iron-sulfur cluster biosynthesis, as primary defects in sideroblastic anemias that may only secondarily impact heme metabolism.
High-performance liquid chromatographic determination of carbaryl in fruit juices.

Presentation d'un protocole de dosage des residus de cet insecticide du groupe des carbamates dans le domaine des concentrations inferieures a 1 ppb
The clinical impact of HPV tumor status upon head and neck squamous cell carcinomas

Human papillomavirus (HPV) is etiologically responsible for a distinct subset of head and neck squamous cell cancers (HNSCCs). HPV-positive HNSCCs (HPV-HNSCCs) most commonly arise from the oropharynx and are responsible for the increasing incidence of oropharyngeal SCC (OSCC) in the United States (US) and abroad. HPV-positive OSCC (HPV-OSCC) has a unique demographic and risk factor profile and tumor biology. HPV-OSCC patients tend to be white, younger, and have a higher cumulative exposure to sexual behaviors as compared with HPV-negative OSCC patients. HPV-positive tumor status also significantly improves survival, and is indeed the single strongest prognostic factor for OSCC. The mechanisms that underlie the improved prognosis conferred by HPV-positive disease are unknown. The purpose of this review is to describe the clinical impact of HPV status in HNSCC, particularly in OSCC, both in terms of the unique clinic-demographic profile and prognostic implications.
An architecture for energy management in wireless sensor networks

Sensornets are becoming more widely adopted for commercial and scientific use and, in settings where battery replacement or recharging is difficult, it is important that sensornets have long and predictable lifetimes. We thus expect energy management to play an increasingly important role in meeting user requirements. Today, system developers seek a balance between network lifetime and performance, but recent history shows that unexpected and dynamic environmental conditions often scuttle expected energy budgets. For example, many nodes in the Great Duck Island deployment were conjectured to have died prematurely because unexpected overhearing of traffic caused radios to become operational for longer than originally predicted [22]. This pattern was repeated in the Redwoods deployment, but for a supposedly different reason: some nodes seemingly died prematurely because they became disconnected from the wireless network and depleted their batteries trying to reconnect [24]. Even systems augmented with energy harvesting are still susceptible to this type of problem. In the Trio Testbed, seasonal and daily variations in solar power, the angle of inclination of the solar cell, the effect of dirt and bird droppings on the cells, and the inefficiencies in power storage and transfer resulted in node duty cycles ranging from 20% to 100% [5]. The issues with these deployments arise from mistaken assumptions, unforeseen difficulties, and unpredictable environmental dynamics. Solutions to these issues take two extreme approaches. At one extreme, some have proposed runtime adaptation to meet lifetime requirements [16] or energy availability [11, 10]. While promising, these efforts have addressed rather coarse-grained, high-level adaptation – for example, by adjusting sampling rates or varying the system-wide duty cycle – but they remain silent on prioritizing energy usage in a fine-grained and flexible manner. At the other extreme, low-level energy management mechanisms that give direct control over the hardware to multiple entities (e.g. network protocols) can be tedious to implement and difficult to debug because of the lack of any isolation. Arbitration can address the isolation problem, but it does not enable runtime adaptation to varying workloads [12]. We believe that using an energy management architecture would alleviate or even prevent these types of problems. SecEnforcement
Reengineering of design and manufacturing processes

Abstract The development of IDEF tools for modeling and analysis of processes has been motivated by the desire to increase productivity by improving communication and structure of manufacturing systems. Constructing an IDEF model is only one component of a comprehensive process modeling effort. Representing IDEF models as process graphs, performing observational model analysis, and analysis of IDEF model structure are issues addressed in this paper. The paper includes a review of current approaches to IDEF modeling in industry, as well as techniques for analysis of IDEF models. The fundamentals of IDEF0 and IDEF3 are discussed, however, the emphasis of the paper is on model analysis and reengineering design and manufacturing processes. An algorithm for model analysis is presented.
Affinity labeling of ribonucleotide reductase by the 2′,3′-dialdehyde derivatives of ribonucleotides☆

Abstract Ribonucleotide reductase from Corynebacterium nephridii is rapidly inactivated by the 2′,3′-dialdehyde derivatives of CDP (dial-CDP) and ADP (dial-ADP). The analog of CDP causes the progressive inactivation of ribonucleotide reductase activity with K i of 0.26 m m and a maximum inactivation rate of 0.092 min −1 at saturating concentrations of dial-CDP. The modified enzyme remains inactive even after extensive dialysis. The four common nucleoside diphosphates (ADP, GDP, CDP, and UDP) protect the enzyme against inactivation by dial-CDP. Experiments with [ 3 H]dial-CDP, [ 14 C]dial-ADP, and [ 32 P]dial-ADP demonstrate that the nucleoside moieties of these nucleotide analogs become covalently attached to the enzyme and that inorganic pyrophosphate is eliminated. The stoichiometry of this inactivation, determined with [ 3 H]dial-CDP and [ 14 C]dial-ADP, is 0.6–0.8 site modified per subunit of enzyme. The results suggest that the enzyme catalyzes the elimination of pyrophosphate and that the resulting α,β-unsaturated nucleoside dialdehyde or its corresponding α,β-unsaturated dihydroxy-morpholino derivative is attacked by a nucleophilic residue in the active site.
Efficient solution of fluid flow using the generalised conjugate grandient algorithm on a transputer-based machine

Abstract The discretisation of the equations governing fluid flow gives rise to coupled, quasi-linear and non-symmetric systems. The solution is usually obtained by iteration using a guess-and-correct procedure where each iteration aims to improve the solution of the previous step. Each step or outer iteration of the process involves the solution of nominally linear algebraic systems. These systems are normally solved using methods based on the Gauss-Seidel iteration—such as the TDMA. However, these methods generally converge very slowly and can be very time consuming for realistic applications. In this paper, these equations are solved using the Generalised Conjugate Gradient (GCG) algorithm with a simple-to-implement Gauss-Seidel-based preconditioner on a distributed memory message-passing machine. We take advantage of the fact that only tentative improvements to the flow-field are sought during each iteration and study the convergence behaviour of the parallel implementation on a multi-processor environment.
Resonant behavior of a small aperture backed by a conducting body

The problem of an electrically small aperture in a conducting screen backed by a conducting body is analyzed. It is found that aperture-body resonances can occur for which the power transmitted through the aperture backed by a conducting body is much larger than that when the body is not present. An example is an electrically small aperture resonated by a capacitor across its midpoint. In the loss-free case, the transmission cross section of a small resonated aperture is 3\lambda^{2}/4\pi independent of the size or shape of the aperture. For actual conductors, the transmission cross section will be increasingly reduced by conduction loss as the aperture is made smaller.