cssi/SciSciGPT-SciSciNet huggingface dataset:
Disappearance of bovine insulin from plasma in diabetic and normal subjects.

Abstract Disappearance curves for radioiodinated and immunoreactive bovine insulins were determined and analyzed in 30 subjects (5 normal volunteers and 25 diabetic patients). Simultaneous determinations were made of blood glucose and of insulin binding by insulin antibodies. There was significant negative association between the disappearance of bovine insulin from plasma and the insulin-binding level of circulating insulin antibodies. The presence of diabetes, the clinical character of the diabetes (whether stable or unstable), and the presence of chronic diabetic complications, of themselves, had no apparent significant influence that could be separated from the effect of circulating levels of insulin-binding antibodies on the disappearance of bovine insulin from plasma.
The intellectual structure of decision support systems (1971–1989)

Abstract This study aims at identifying the intellectual structure of decision support systems (DSS), using factor analysis and multidimensional scaling of author cocitation frequency. Eight subsets of DSS research are identified; they are foundations, group DSS, routing DSS, data base management systems, multiple criteria DSS, marketing DSS, multiple criteria decision making, and management science. Earlier studies by Culnan reported that management information systems (MIS) have made significant progress toward a cumulative research tradition. This study extends the study of Culnan and examines a subspecialty of eight areas of MIS research identified by prior research. Contrary to the prior research, this research supports the theory of continuing fragmentation of DSS research and finds very little cumulative research tradition. Further, this study suggests that DSS research should be directed toward the improvement of organizational decision making.
Cognitive therapy for chronic depression.

Recent literature indicates that there are important clinical differences between chronic and non-chronic depression. This article considers the implications of these differences when conducting cognitive therapy (CT) with chronically depressed patients. CT with chronic patients requires a greater emphasis on combating hopelessness, helplessness, and perfectionism, addressing early life-adverse experiences, and modifying maladaptive schemas. In addition, the effectiveness of CT may be enhanced by focusing on patients' poor social skills, ineffective reasoning skills, and their depressive identity. The case example presented illustrates CT with a chronically depressed patient.
Edward C. Prescott's contributions to economics: Guest editors' introduction

It is a privilege for us at Economic Theory to be able to honor Edward C. Pres cott by publishing this set of papers. Ed was one of the founding members of the Society for the Advancement of Economic Theory (SAET) and its first President. He has been a co-Editor of Economic Theory since its inception, and an impor tant contributor to Economic Theory having published numerous papers within its pages, including one paper with Finn Kydland in the inaugural issue in 1991. Thus it gives us particular pleasure to honor him for his contributions to Economic Theory and SAET, his Nobel Prize with Finn, and more fundamentally for a career of pioneering work. Quite literally, without Ed's leadership Economic Theory and SAET would not have been founded and enjoyed the success they have. When Economic Theory first sought out our assistance in putting together this special issue honoring Ed, the question that immediately went through our minds was how to optimally set the criteria for soliciting papers. On the one hand, we wanted to ensure that only papers consistent with the high quality standard asso ciated with Ed's own work be published. This suggested we cast a wide net. On the other hand, we faced a short time horizon of a June 2007 publication date. This suggested we cast a narrow net. As it turned out, the answer was simple; we could both ensure a high quality set of papers and manage the refereeing and editing process in time for the publication target date by limiting submissions to Ed's co-authors and former students.
A fast, time-accurate, unsteady full potential scheme

The unsteady form of the full potential equation is solved in conservation form by an implicit method based on approximate factorization. At each time level, internal Newton iterations are performed to achieve time accuracy and computational efficiency. A local time linearization procedure is introduced to provide a good initial guess for the Newton iteration. A novel flux-biasing technique is applied to generate proper forms of the artificial viscosity to treat hyperbolic regions with shocks and sonic lines present. The wake is properly modeled by accounting not only for jumps in phi, but also for jumps in higher derivatives of phi, obtained by imposing the density to be continuous across the wake. The far field is modeled using the Riemann invariants to simulate nonreflecting boundary conditions. The resulting unsteady method performs well which, even at low reduced frequency levels of 0.1 or less, requires fewer than 100 time steps per cycle at transonic Mach numbers. The code is fully vectorized for the CRAY-XMP and the VPS-32 computers.
The Postabsorptive Hydroxyproline in the Long‐Term Evaluation of Patients With Breast Cancer

The postabsorptive urinary hydroxyproline excretion test (Spot-HYPRO) was evaluated for its usefulness in reflecting the presence or absence of bone metastasis in 75 women with breast cancer. A comparison was made between the Spot-HYPRO values and bone disease, as documented by bone scanning supported by skeletal x-rays. Breast cancer patients with skeletal metastasis had 3-4-fold elevations in Spot-HYPRO above the control values (P less than 0.001). Mild elevations were noted in breast cancer patients without skeletal metastasis (P less than 0.025). Thirty patients received serial Spot-HYPRO and bone scans for 6 to 48 months (average, 24 months). There was a 90% correlation between changes in Spot-HYPRO and simultaneous changes on bone scan. Elevations in Spot-HYPRO preceded changes found on bone scan by an average of 3 months. The authors conclude that the Spot-HYPRO is a simple, convenient, and accurate method of documenting and following bone metastasis in patients with breast cancer.
Selection of micro-organisms in a spatially explicit environment and implications for plant access to nitrogen

Summary Evolution of a microbial nitrogen-uptake strategy that removes nitrogen at less than the maximum potential rate creates soil environments favourable for increased plant access to nitrogen. Plant productivity is thus increased, and achievement of maximum microbial biomass is facilitated through increased microbial access to plant-derived carbon. Simulations show that micro-organisms exhibiting such a ‘strategic’ nitrogen uptake will be competitively excluded by more voracious micro-organisms in a homogeneous system, but can persist in a spatially explicit system. This persistence of less voracious micro-organisms contrasts with the frequently held view that micro-organisms in soil systems take up nitrogen at the maximum possible rate. The selection of strategic or voracious microbial types in a spatially explicit environment is sensitive to the frequency of plant and microbial disturbance, and to the rate of diffusion of inorganic nitrogen in the soil system. In particular, the strategic (less voracious) microbial types are favoured under conditions of low plant disturbance, low to moderate diffusion of inorganic nitrogen, and moderate microbial disturbance. When selection favours strategic microbial types, plant access to nitrogen is increased. Plants may also evolve strategies in a spatially explicit environment that will increase population densities of favourable, strategic microbial types.
Scattering of acoustic waves by elastic and viscoelastic obstacles immersed in a fluid

Abstract A scattering or T -matrix approach is presented for studying the scattering of acoustic waves by elastic and viscoelastic obstacles immersed in a fluid. A Kelvin-Voigt model is used to obtain the complex elastic moduli of the viscoelastic solid. The T -matris formulation is somewhat complicated because the wave equations and fields are quite different in the solid and fluid regions and are coupled by continuity conditions at the interface. We have obtained fairly extensive numerical results for prolate and oblate spheroids for a variety of scattering geometries. The backscattering, bistatic, absorption and extinction cross-section are presented as a function of the frequency of the incident wave.
Efficacy of natural wetlands to retain nutrient, sediment and microbial pollutants.

Wetlands can improve water quality through natural processes including sedimentation, nutrient transformations, and microbial and plant uptake. Tailwater from irrigated pastures may contribute to noripoint source water pollution in the form of sediments, nutrients, and pathogens that degrade downstream water quality. We examined benefits to water quality provided by a natural, flow-through wetland and a degraded, channelized wetland situated within the flood-irrigation agricultural landscape of the Sierra Nevada foothills of Northern California. The non-degraded, reference wetland significantly improved water quality by reducing loads of total suspended sediments, nitrate, and Escherichia coli on average by 77, 60, and 68%, respectively. Retention of total N, total P, and soluble reactive P (SRP) was between 35 and 42% of loads entering the reference wetland. Retention of pollutant loads by the channelized wetland was significantly lower than by the reference wetland for all pollutants except SRP. A net export of sediment and nitrate was observed from the channelized wetland. Decreased irrigation inflow rates significantly improved retention efficiencies for nitrate, E. coli, and sediments in the reference wetland. We suggest that maintenance of these natural wetlands and regulation of inflow rates can be important aspects of a best management plan to improve water quality as water runs off of irrigated pastures.
The Role of Melanocortins in Adipocyte Function

It has been demonstrated that adipocytes express high affinity ACTH and alpha-MSH binding sites, and that ACTH, alpha-MSH, and beta-LPH are potent lipolytic hormones. Considerable species variability exists in the lipolytic response to melanocortins, however. Recently, MC2 and MC5 receptor-mRNA was found in both murine adipocytes and in the 3T3-L1 murine embryonic fibroblast cell line, but only after the 3T3-L1 cells had differentiated into adipocytes. The 3T3-L1 cell line was used to characterize the pharmacological properties of both MC2 and MC5 receptors in situ. Both murine MC2 and MC5 receptors are functional in the adipocyte, although the MC5 receptor required high doses of alpha-MSH to activate cylase. ACTH potently stimulates cyclase with EC50 values that are consistent with the hypothesis that the murine MC2 receptor, not the MC5 receptor, mediates stress-induced lipolysis via release of ACTH from the pituitary.
Game theory: applications for surgeons and the operating room environment.

Background Game theory is an economic system of strategic behavior, often referred to as the “theory of social situations.” Very little has been written in the medical literature about game theory or its applications, yet the practice of surgery and the operating room environment clearly involves multiple social situations with both cooperative and non-cooperative behaviors. Methods A comprehensive review was performed of the medical literature on game theory and its medical applications. Definitive resources on the subject were also examined and applied to surgery and the operating room whenever possible. Results Applications of game theory and its proposed dilemmas abound in the practicing surgeon's world, especially in the operating room environment. Conclusion The surgeon with a basic understanding of game theory principles is better prepared for understanding and navigating the complex Operating Room system and optimizing cooperative behaviors for the benefit all stakeholders.
Neuropathologic findings in a case of OFDS type VI (Váradi syndrome)

Oral-facial-digital syndrome type VI (OFDS VI) or Varadi syndrome is a rare autosomal-recessive disorder distinguished from other oral-facial-digital syndromes by metacarpal abnormalities with central polydactyly and by cerebellar abnormalities. Histopathologic characterization of the cerebellar abnormalities has not been described previously. We describe the neuropathologic findings in a stillborn, 21-week estimated gestational age (EGA) male fetus diagnosed antenatally with signs of OFDS VI. Autopsy findings included: facial abnormalities, postaxial central polydactyly of the right hand, bilateral bifid toes, and absence of cerebellar vermis with hypoplasia of the hemispheric cortex. Microscopic analysis of the cerebellum demonstrated absence of the subpial granular cell layer and disruption or dysgenesis of the glial architecture. These histopathologic findings suggest that a primary neuronal or glial cell defect, rather than an associated Dandy-Walker malformation, may account for the cerebellar abnormalities in this form of oral-facial-digital syndrome. Am. J. Med. Genet. 77:38–42, 1998. © 1998 Wiley-Liss, Inc.
A pharmacologic comparison of 3,4-methylenedioxyamphetamine and LSD in the chronic spinal dog.

Abstract MDA (2.0 and 2.2 mg/kg) was compared to LSD (10 μg/kg) and d-amphetamine (3.2 mg/kg) in single dose, antagonism, cross tolerance and appetite suppression studies. In single doses MDA specifically resembled d-amphetamine by producing marked mydriasis, nictitating membrane retraction, stereotypy and darting eye movements and LSD by markedly facilitating the flexor reflex, producing continuous stepping, whining and eye tracking movements. LSD and MDA increased respiration, body temperature and the latency of the skin twitch reflex and produced behavioral arousal. Cypropheptadine antagonized the effects of LSD but was ineffective against MDA. Phenoxybenzamine antagonized the respiratory, pupillary and hyperthermic effects of MDA and the respiratory effect of LSD. Chlorpromazine antagonized many of the effects of LSD and MDA. Spinal dogs were made tolerant to the behavioral and physiologic effects of LDS. Cross tolerance developemd to some but not all of the effects of MDA. In intact dogs MDA was 1/10 as potent as d-amphetamine in suppressing appetite. It is concluded that MDA has properties resembling both LSD and amphetamine.
Repetitive firing properties in subpopulations of the chick Edinger Westphal nucleus.

The avian Edinger Westphal nucleus, through the ciliary ganglion, controls accommodation, iris constriction, and blood flow through the choroid. In live brainstem slices, the nucleus is easily identifiable as an olive-shaped cluster of neurons dorsal to the oculomotor nerve and nucleus. Intracellular recordings from neurons in the nucleus identified two classes of responses to sustained (300 to 500 ms) injections of depolarizing current. One set of cells fired action potentials for the duration of the pulse while a second set of cells fired action potentials only transiently, during the first 50 to 100 ms, after which they remained silent regardless of the size of the depolarization. Intracellular recordings followed by injections of the fluorescent dye lucifer yellow revealed that repetitively firing cells were located in the lateral half of the nucleus while non-repetitively or transiently firing cells were located in the medial half. These locations correspond to different Edinger Westphal subdivisions which have distinct inputs and target populations. The varying firing patterns are discussed with reference to the known functions of the subdivisions in which they occur. Replacement of calcium by magnesium in the extracellular medium had no effect on the number of action potentials fired by non-repetitively firing cells, suggesting that a calcium-activated potassium current is not responsible for suppressing repetitive firing in these cells. In contrast, in repetitively firing cells removal of extracellular calcium increased the frequency of action potential discharge and decreased the amplitude of afterhyperpolarizations following single action potentials. Addition of cadmium to the bath medium had similar effects. This suggests the presence of a significant calcium-activated potassium current and involvement of this current in regulating the frequency of action potential discharge.
Itanium's new basic operation of fused multiply-add: theoretical explanation and theoretical challenge

A new Intel's 64-bit chip Itanium has a new instruction set which includes a fused multiply-add instruction x1 + x2 · x3 (see, e.g., [7]). In this short article, we explain the empirical reasons behind the choice of this instruction, give possible theoretical explanation for this choice, and mention a related theoretical challenge.
Myxosarcoma of prostate

Abstract Myxosarcoma of the prostate is of rare occurrence. The clinical diagnosis is frequently difficult due to the fact that most of these patients are seen late in the disease. Pelvic tumors of mesothelial origin may arise in the retrovesical tissue and bladder and the prostate become so completely invaded as to make the diagnosis of the primary site of the tumor impossible. A case of myxosarcoma of the prostate in a white male age forty-six years, is reported. The patient was observed early in the disease when the pathological process was limited entirely to the prostate gland.
Blood-pressure-related risk factors, stroke, and cognitive function: What are the relationships and what can we do about them?

Abstract Blood pressure, particularly systolic pressure, is a major risk factor for stroke and cognitive decline. Lowering elevated blood pressure, especially systolic pressure, reduces both initial and recurrent stroke and the occurrence of dementia. This article also reviews the early morning surge in blood pressure, lipids and insulin resistance, diabetes mellitus as additional stroke risk factors, as well as left ventricular hypertrophy.
Systematic self-selection and sample weight creation in panel surveys: The Puget Sound Transportation Panel case

The Puget Sound Transportation Panel (PSTP) is a survey that contains sampling stages which lessen the sample's representativeness of the Puget Sound region. This paper presents an analysis of survey participation and a method for sample weight creation when systematic self-selection in survey participation can be detected and accounted for. The method uses probability of participation models for selected stages of the survey to first identify determinants of participation and then create sample weights. A variety of weight schemes are thus derived and used to correct for systematic self-selection in panel participation. The performance of these sample weights is tested using as a benchmark sample the Public Use Microdata Sample (PUMS) from the census of 1990 in the U.S.
EXPANDED USES OF SURFACTANT THERAPY

There are few therapies for which the cumulative evidence of benefit is as much as that for surfactant therapy for RDS in premature infants. Exogenous surfactant therapy does seem to be beneficial for a number of non-RDS disorders. Although there are some trials supporting its use in MAS and ALI-ARDS, there are only a few small prospective, randomized, controlled trials supporting surfactant use in non-RDS disorders. Use of surfactant therapy for any disorder other than RDS must be considered "off the shelf" and experimental. Much work remains to be done to address the role of surfactant therapy in the myriad disorders discussed. Of import for each of the disorders is addressing the optimum type of surfactant to use, and the appropriate dose, method of delivery, and duration of treatment regimens.
Speech waveform compression using robust adaptive voice activity detection for nonstationary noise

The voice activity detection (VAD) is crucial in all kinds of speech applications. However, almost all existing VAD algorithms suffer from the nonstationarity of both speech and noise. To combat this difficulty, we propose a new voice activity detector, which is based on the Mel-energy features and an adaptive threshold related to the signal-to-noise ratio (SNR) estimates. In this paper, we first justify the robustness of the Bayes classifier using the Mel-energy features over that using the Fourier spectral features in various noise environments. Then, we design an algorithm using the dynamic Mel-energy estimator and the adaptive threshold, which depends on the SNR estimates. In addition, a realignment scheme is incorporated to correct the sparse-and-spurious noise estimates. Numerous simulations are carried out to evaluate the performance of our proposed VAD method and the comparisons are made with a couple of existing representative schemes, namely, the VAD using the likelihood ratio test with Fourier spectral energy features and that based on the enhanced time-frequency parameters. Three types of noises, namely, white noise (stationary), babble noise (nonstationary), and vehicular noise (nonstationary) were artificially added by the computer for our experiments. As a result, our proposed VAD algorithm significantly outperforms other existing methods as illustrated by the corresponding receiver operating characteristics (ROC) curves. Finally, we demonstrate one of the major applications, namely, speech waveform compression associated with our new robust VAD scheme and quantify the effectiveness in terms of compression efficiency.
Tumour angiogenic factor associated with subcutaneous lymphoma.

SUMMARY Growth and survival of cutaneous neoplasms are dependent on the development of a nutrient-supply ing vascular lifeline. A subcutaneous lymphoma is described which mimicked a vascular neoplasm because of the extensive telangiectasia overlying the tumour. Fragments of the lymphoma inserted in direct apposition to the hamster cheek pouch membrane or separated from the membrane by a microporous filter both induced dramatic neovascularization. Control materials failed to induce significant vascular changes. A diffusablc Tumour Angiogenic Factor may play a vital role in tumour survival and portends a therapeutic potential.
New approximate model for nonlinear adsorption and diffusion in a single particle

A new approximate model of the general adsorption and diffusion model is derived that describes gas and adsorbed phase dependent diffusion in a single spherical sorbent particle governed by a nonlinear adsorption isotherm. This new approximate model compares very well with the exact (numerical) solution of the general adsorption and diffusion model over a wide range of (Langmuir) isotherm nonlinearity, and pore and surface diffusivities. Thus, it provides a significant advantage in terms of computation compared to the exact (numerical) model. This new model is simple to use and far superior to the popular linear driving force model, which severely underpredicts the uptake curve (compared to the new model) unless the adsorption isotherm is very favorable and the bulk concentration is low, approaching the Henry's law region of the isotherm.
Hydrogen energetics in a − S i : H as determined by a combination of mean-field modeling and experimental evolution data

The energetics of hydrogen configurations in amorphous silicon ($a\ensuremath{-}\mathrm{S}\mathrm{i}:\mathrm{H}$) and hydrogen populations associated with these configurations remain an important unresolved issue. To date, hydrogen evolution data have been difficult to analyze due to lack of models accurately describing the coupling of the thermally activated reaction/diffusion/desorption processes, that control evolution. A rigorous mathematical model for hydrogen transport in, and evolution from $a\ensuremath{-}\mathrm{S}\mathrm{i}:\mathrm{H}$ is described and validated here. The model improves on other evolution models by including three discrete hydrogen energy levels in the film, one mobile level and two independent trap levels, and by explicitly simulating adsorption/desorption processes at the surface. This multienergy level model with a floating boundary condition at the surface is used to simulate two types of evolution experiments: temperature programed evolution and isothermal evolution. Results from both types of experiments for glow discharge deposited films are modeled using the same energetics, with trap depths of 1.5 and 1.8--1.9 eV below the transport level, and 20--30 % of hydrogen residing in the deep traps. These results contrast past experimental analysis, which suggested that hydrogen in deep traps is more tightly bound, 2.1--3.4 eV below the transport level. The difference of 0.3--0.4 eV we observed between the two trap energy levels agrees well with published bonding energies estimated using ab initio quantum-mechanical calculations. The difference in trap energies is also similar to the measured defect formation activation energy of 0.2--0.5 eV, suggesting that the defect formation mechanism in $a\ensuremath{-}\mathrm{S}\mathrm{i}:\mathrm{H}$ may involve hydrogen motion between the two energy levels. Combination of our results with quantum-mechanical calculations of various hydrogen energy levels in crystalline silicon suggests that the interstitial hopping may not be the primary hydrogen transport mechanism.
Transcription of laminin γ1 chain gene in rat mesangial cells : constitutive and inducible RNA polymerase II recruitment and chromatin states

The laminin γ1 chain, a critical component of the extracellular matrix, is encoded by the 125-kb-long Lamc1 locus. We profiled RNA polymerase II (Pol II) and histone modifications along the Lamc1 l...
Statistical analysis of a compound exponential failure model

This paper discusses the statistical analysis of a two parameter mixed(or compound)exponential failure model. This model is also a Pareto distribution of the second kind. Some computational aspects of estimating both parameters by the method of maximum likelihood are discussed and small-sample means and variances are derived and studied. Tests of hypotheses on each parameter with the other parameter an unknown nuisance parameter are provided, and the construction of confidence limits are discussed.
Procoagulant and fibrinolytic activity in ventilator-associated pneumonia: impact of inadequate antimicrobial therapy

To determine the homeostatic balance of patients with ventilator-associated pneumonia (VAP) with respect to the adequacy of antimicrobial therapy. Descriptive observational study in a 12-bed medical intensive care unit in a university-affiliated hospital. Twenty-nine patients with VAP documented by quantitative culture of bronchoalveolar secretions and a control group of eight mechanically ventilated patients. Serial bronchoalveolar lavage fluid (BALF) samples were assayed for prothrombin activation fragment (F1+2), thrombin-antithrombin (TAT) complex, fibrinolytic activity, urokinase-type plasminogen activator (u-PA), and plasminogen activator inhibitor type 1 (PAI-1) on days 1, 4, and 7 after VAP onset. Pathogens isolated from patients with inadequate empirical antimicrobial coverage included methicillin-resistant Staphylococcus aureus (n=2), Pseudomonas aeruginosa (n=4), and Acinetobacter baumannii (n=1). Compared to those who received adequate antibiotic therapy, TAT, F1+2, and PAI-1 levels increased while u-PA levels remained unchanged. Despite antibiotic adjustment on day 4, TAT levels remained elevated in those who lacked adequate antimicrobial coverage and were significantly correlated with PaO2/FIO2. The procoagulant activity was accompanied by a local depression of fibrinolytic capacity that was attributed mainly to increased BALF PAI-1 levels. Nonsurvivors showed significantly higher levels of TAT and PAI-1 than survivors. No significant correlation between the bacterial burden and the homeostatic derangements was documented. The lung inflammatory response seems to promulgate a local procoagulant activity associated with hypoxemia in those with inadequate antibiotic therapy. The homeostatic derangement seems to be independent of the lung bacterial burden.
Behavioural neurobiology: The treacherous scent of a human

Mosquitoes' odorant receptors help the insects to find humans and, inadvertently, to transmit malaria. The identification of the odorants that bind to these receptors opens up ways of reducing mosquito biting.
Characterization of Collision Cascade Damage in Ca2La8(SiO4)6O2 by Hrtem

Ca2La8(SiO4)6O2 thin crystals become amorphous under ion beam irradiation. The ion dose required for complete amorphization of the thin crystal (critical amorphization dose, Dc) increased with the increasing irradiation temperature and decreased with ion mass at elevated temperatures. Samples irradiated with 1-1.5 MeV Ar+, Kr+ and Xe+ ions to doses much lower than Dc, in the temperature range from 20 to 498 K were used for a detailed HRTEM investigation to study the amorphization process. The residual collision cascade damage after irradiation appeared as nanometer scale amorphous domains. The images of these domains are extremely sensitive to the sample thickness. Small domains of cascade size were found only at the very thin edge of the sample. In thicker regions, amorphous domains appear after higher doses as the result of cascade overlap in projection. At higher temperatures, the observed amorphous domains are smaller indicating thermal recovery at the amorphous/crystalline interface. The amorphous domains are also larger in size after irradiation with ions of higher mass at a fixed ion dose. These results are consistent with the Dc-temperature curves determined by in situ TEM with the HVEM-Tandem Facility at Argonne National Laboratory. The width of the amorphous rim along the edge of the specimen grew with increasing ion dose suggesting that amorphization also proceeds from the sample surface. Images of the collision cascade damage were compared to the cascade sizes calculated with the TRIM code. Some digitally acquired HRTEM images of the cascade damage were processed to reveal more detailed information.
Identification of the Dynamic Behavior of Surrogate Explosive Materials

Improvised explosive devices are often made to resemble objects that are a natural part of the environment. It is hypothesized that by understanding the mechanical behavior of the explosive material it may be possible to tune an acoustic excitation to produce signatures that indicate explosives are present in an object. Here the focus is on identification of mechanical material properties and their effect on a system’s dynamic response. Energetic material surrogates were produced by embedding inert crystals within the binder. Swept-sine wave base-excitation tests were conducted to examine repeatability of the material-mass system responses. Compression test data were fitted using a two-term Ogden model but for a massmaterial base-excited system a continuous-time system identification method was used to estimate model parameters. Damping ratios of 0.11 for the 0% (no crystals) material and 0.19 for the 50% (crystal volume fraction) material were estimated. Future work includes examination of models that include a hereditary model of viscoelasticity and nonlinear terms, and experimental investigations at higher forcing levels.Copyright © 2013 by ASME
The MES-2/MES-3/MES-6 Complex and Regulation of Histone H3 Methylation in C. elegans

Abstract The C. elegans proteins MES-2 and MES-6, orthologs of the Polycomb group (PcG) chromatin repressors E(Z) and ESC [1, 2], exist in a complex with their novel partner MES-3 [3]. The MES system participates in silencing the X chromosomes in the hermaphrodite germline [4, 5]. Loss of maternal MES function leads to germline degeneration and sterility [6]. We report here that the MES complex is responsible for di- and trimethylation of histone H3 Lys27 (H3-K27) in the adult germline and in early embryos and that MES-dependent H3-K27 marks are concentrated on the X's. Another H3-K27 HMT functions in adult somatic cells, oocytes, and the PGCs of embryos. In PGCs, the MES complex may specifically convert dimethyl to trimethyl H3-K27. The HMT activity of the MES complex appears to be dependent on the SET domain of MES-2. MES-2 thus joins its orthologs Drosophila E(Z) and human EZH2 among SET domain proteins known to function as HMTs (reviewed in [7]). Methylation of histones is important for long-term epigenetic regulation of chromatin and plays a key role in diverse processes such as X inactivation and oncogenesis [8]. Our results contribute to understanding the composition and roles of E(Z)/MES-2 complexes across species.
Human recombinant stem-cell factor induces melanocytic hyperplasia in susceptible patients

Abstract Background: Recombinant human stem-cell factor (SCF), a cytokine acting on hematopoietic progenitor cells, has potential for the treatment of several hematologic and oncologic disorders. In a hematology-oncology phase I trial of SCF, several patients had cutaneous hyperpigmentation at the SCF subcutaneous injection sites. Objective: Our purpose was to investigate the pathogenesis of this hyperpigmentation phenomenon. Methods: Skin biopsy specimens were obtained before, at the completion of, and after SCF therapy and were processed for histology, immunohistology, and electron microscopy. Results: Skin at the site of SCF injection had an increased number of melanocytes, increased melanocytic dendrite extension, and melanin as compared with noninjected tissue. Immunohistochemical stains revealed an increase in staining with melanocyte-specific monoclonal antibodies HMB-45 and NKI/beteb, and a monoclonal antibody to the receptor for SCF, c-kit. Conclusion: Subcutaneous injection of SCF results in hyperplasia of melanocytes. SCF may be useful in the treatment of melanocytopenic disorders, but caution may be necessary in patients with disorders of melanocyte proliferation.
Modeling of fatigue crack growth threshold development for a microstructurally small crack

Abstract A method for predicting the fatigue crack growth threshold using finite element analysis is investigated. The proposed method consists of monitoring the plastic strain hysteresis energy dissipation in the crack tip plastic zone, with the threshold being defined in terms of a critical value of this dissipated energy. Two-dimensional plane-strain elastic–plastic finite element analyses are conducted to model fatigue crack growth in a middle-crack tension M(T) specimen. A single-crystal constitutive relationship is employed to simulate the anisotropic plastic deformation near the tip of a microstructurally small crack without grain boundary interactions. Variable amplitude loading with a continual load reduction is used to generate the load history associated with fatigue crack growth threshold measurement. Load reductions with both constant load ratio R and constant maximum stress intensity Kmax are simulated. In comparison with a fixed Kmax load reduction, a fixed R load reduction is predicted to generate a 35% to 110% larger fatigue crack growth threshold value.
Chemical Composition of the Interstellar Gas: X-Ray Determinations

Noting that observations of X-ray attenuation at theK-shell ionization edge for many elements provide, prospectively, the least ambiguous means for establishing the chemical composition of the interstellar gas, we have evaluated the expected spectral discontinuities for all atoms from carbon to sodium and have tabulated the results. It is shown that with X-ray detectors of reasonable energy resolution and sensitivity theK-shell edges of C, N, O, Ne, Si, S, A and Mg are potentially observable if the ‘cosmic’ abundances are representative of the general interstellar environment.
Distribution of Motor Cortical Neuron Synaptic Terminals on Monkey Parvocellular Red Nucleus Neurons

We determined the location of 54 horseradish peroxidase (HRP)-labeled motor cortical neuron synaptic terminals on 17 parvocellular neurons in the monkey red nucleus. Synaptic terminals and their postsynaptic elements were identified and reconstructed, using light- and electron-microscopic techniques, from serial thick and thin sections. Terminals were found on proximal and distal dendrites of small and medium-sized parvocellular neurons, where they formed excitatory synapses. Some were 180 μm from cell somata. Approximately half of the labeled terminals, aside from those located at dendritic origins, were situated strategically at or near dendritic branch points. Since monkey parvocellular neurons show little activity during movement, the obvious next question is this: How and in what way does motor cortex influence these cells?
Chlamydia trachomatis secretion of hypothetical protein CT622 into host cell cytoplasm via a secretion pathway that can be inhibited by the type III secretion system inhibitor compound 1.

Using antibodies raised with C. trachomatis fusion proteins, we localized a hypothetical protein encoded by the ORF ct622 in the cytoplasm of C. trachomatis-infected mammalian cells. The detection was specific since the antibody labelling of CT622 protein was removed by preabsorption with CT622 but not other fusion proteins. We similarly confirmed that CT621, a known secretion protein encoded by a hypothetical ORF downstream of ct622, was secreted into host cell cytosol. Proteins CT622 and CT621 displayed a similar secretion pattern, with both intra-inclusion and host cell cytosol localization, that was distinct from that of CPAF (chlamydial protease/proteasome-like activity factor). However, the expression and secretion kinetics differed significantly between CT622 and CT621: CT622 mRNA was detected at 2 h, protein at 6 h and secretion of protein into host cell cytoplasm at 36 h post-infection, while CT621 mRNA was detected at 8 h, protein at 16 h and secretion at 24 h. The secretion of both CT622 and CT621 was blocked by N′-(3,5-dibromo-2-hydroxybenzylidene)-4-nitrobenzohydrazide (compound 1), an inhibitor known to target the type III secretion system of bacteria. These results suggest that CT621 and CT622 may fulfil different functions during chlamydial intracellular growth. Further characterization of these proteins may generate important information for understanding chlamydial pathogenesis.
The inter-group router approach to scalable group composition

This paper examines the problem of building scalable, fault-tolerant distributed systems from collections of communicating process groups, while maintaining well-defined end-to-end delivery semantics. We propose a new architecture which supports modular group composition by providing a distinction between intra-group and inter-group communication. With this architecture, multiple group communication protocols and end-to-end delivery semantics can be used in a single system. These features reduce the complexity of ordering messages in a group composition, resulting in enhanced scalability. Finally we present simulation results comparing the performance of a group composition using our architecture to that of a single process group.
The Bark and Bite of International Organizations in Implementing International Agreements

International Organizations and Implementation: Enforcers, Managers, Authorities? Edited by Jutta Joachim, Bob Reinalda, Bertjan Verbeek. Routledge/ECPR Studies in European Political Science, 2008. 224 pp., $140 hardcover (ISBN: 978-0-415-39788-9). The variety of roles now played by international organizations (IOs), some new and some old, has rekindled scholarly interest in the study of IOs, resuscitating a field that in the 1980s appeared to have been abandoned as IR scholars moved on to other “broader forms of international institutionalized behavior”—in particular, international regimes—that seemed to better explain actual behavior in international relations (Kratochwil and Ruggie 1986:753–755; Rochester 1986; Senarclens 1993). This renaissance actually began with the end of the Cold War and has been spurred on by globalization and the technological revolution that have significantly altered the international political, economic and social landscape, especially the relationships between states, international business enterprises, and civil society, as well as the roles and functions of IOs within the rapidly changing international system of governance (Bruhl and Rittberger 2002). The growing interest in IOs, though, is not only among scholars of international relations, but also in other disciplines—such as policy studies, management, and public administration—that are bringing to bear new and different perspectives on and approaches to the study of IOs (Reinicke 1998; Dijkzeul and Beigbeder 2003; Muldoon 2003; Van Tulder with van der Zwart 2006). Today, research on IOs has become more inter-disciplinary …
Transition from Water to Land in Decapod Crustaceans

In the Order Decapoda four families of Macrura, one of Anomura, and seven of Brachyura include semi-terrestrial or terrestrial representatives, primarily tropical and subtropical in distribution. Observations have been made largely on brachyurans. In these forms mating takes place on land, and courtship involves mainly visual and acoustic signals rather than chemical and tactile ones. During copulation the female is often hard rather than soft and may assume a position above the male rather than beneath him, as in many marine forms. Eggs are carried by the female on land. Larval development takes place either in sea water or, in the case of some fresh-water crayfishes and crabs, entirely within the egg. Extremes of temperature are met primarily by acclimation, transpiration, or escape (immersion, burrowing). During transpiration body temperature is lowered by a few degrees but water is lost. In some species water can be replenished by uptake from a moist substratum and stored within the pericardial sacs. Ionic regulation occurs largely through antennal glands, gills, and gut and helps to move water from exterior into hemolymph and from hemolymph into gut and its diverticula. In Gecarcinus lateralis at ecdysis, large amounts of water move from hemolymph into gut, this process being controlled by a hormone from the thoracic ganglionic mass.
Electromechanical Impedance Modeling

The electromechanical impedance method is one of the key structural health monitoring (SHM) technologies enabling real-time in-service assessment of structural condition. This SHM method utilizes permanently attached piezoelectric wafer active sensors and electromechanical impedance measurements for inferring dynamic characteristics (frequency response) of the host structure. Changes in the impedance signatures serve as a diagnostic for structural damage. Providing a fundamental consideration of the sensor–structure impedance interaction, this article focuses on the analytical modeling of the sensor and structural dynamics participating in the cumulative impedance response. One-dimensional models of the sensor and the host structure are discussed first to introduce the reader to the physical mechanisms of the electromechanical impedance method. Under applied harmonic excitation, expansion and contraction of the sensor results in longitudinal and flexural vibrations of the host structure that are accounted for in the model presented. For two-dimensional structures, an axisymmetric problem is considered and an analytical formulation is derived for the electromechanical impedance as seen at the sensor terminals. Extensional and transverse dynamics of the plate structure are included in the model. Recent developments in impedance modeling are discussed and prospective new trends are suggested. Keywords: electromechanical impedance; smart structures; in situ sensors; embedded diagnostics; piezoelectric sensors; electromechanical analysis; frequency response function; FRF; EMI; SHM; PWAS
PANEL DATA ANALYSIS OF REGULATORY FACTORS SHAPING ENVIRONMENTAL PERFORMANCE

This is the publisher's version, also available electronically from http://www.mitpressjournals.org/doi/abs/10.1162/003465304323023895#.U1q6GIUvDGI.
Chapter 3 Unusual anharmonic local mode systems

Publisher Summary Early far infrared measurements with grating instruments on the low temperature properties of defects in alkali halides produced a variety of sharp features associated with local modes, gap modes, and resonant modes. The loss of periodicity in defect crystals lead to localized vibrational phenomena. The standard description of the dynamics of defect-free periodic lattices in terms of plane wave phonons is so deeply ingrained that it was surprising to many researchers that the presence of strong quartic anharmonicity in perfect lattices can also lead to localized vibrational modes, called “intrinsic localized modes” (ILMs). These papers studied the classical vibrational dynamics of a simple one-dimensional monatomic chain of particles interacting via nearest-neighbor harmonic and quartic anharmonic springs, and they used a rotating wave approximation (RWA), in which just one frequency component was kept in the time dependence. For the case of sufficiently strong positive quartic anharmonicity, it was found that the lattice could sustain stationary localized vibrations having the approximate mode pattern. This pattern is odd under reflection in the central site and is optic mode-like, in that adjacent particles move out of phase. As with all nonlinear vibrations, the ILM frequencies are amplitude dependent. The ILMs can be centered on any lattice site, giving rise to configurational entropy analogous to that for vacancies, and some thermodynamic ramifications, along with speculations about the possible presence of ILMs in strongly anharmonic solids, such as solid He and ferroelectrics.
Shallow Water Flow on the Sphere

The vector spherical harmonic spectral transform method is used to compute nonlinear time-dependent shallow water flows on the sphere. Several computational experiments are performed. The first consists of a Gaussian geopotential dome on a steady sphere that collapses while producing a wave that travels from the dome and reconstructs at its antipole. The reconstruct is not identical because the flow is nonlinear. The flow continues to travel between the poles and remains smooth until day 7 when it develops a sharp spicule at its original position. Near corners in the velocity appear to develop at earlier times. The method is quite stable without either implicit or explicit smoothing either in space or time. The two-thirds rule is not required, and the solutions converge quadratically corresponding to the temporal error. The second experiment starts with a Gaussian vortex dome on a steady sphere. The vortex dome does not collapse but rather is sustained by a geopotential low that develops early in the flow. The third experiment is the same as the first but on a rotating sphere. The resulting flows are considerably different as demonstrated by an apparent lack of singularities.