cssi/SciSciGPT-SciSciNet huggingface dataset:
Is liraglutide a useful addition to diabetes therapy

ABSTRACT Objective To evaluate liraglutide as an antidiabetic agent. Methods The pertinent English-language medical literature was reviewed for the period from 1985 to April 2010 with use of data from MEDLINE. Results Liraglutide is a glucagonlike peptide-1 receptor analogue that stimulates insulin secretion, reduces postprandial glucagon release, causes a mild delay in gastric emptying, and may slightly decrease appetite. Mean reductions in hemoglobin A1c levels with liraglutide therapy range from 1.0% to 1.5% in comparison with baseline and are 1.0% and 1.3% in comparison with placebo. Head-to-head trials suggest that liraglutide may be more effective than glimepiride, rosiglitazone, insulin glargine, and exenatide. Some of the previous trials, however, are limited by use of submaximal doses of comparator drugs and an open-label design. The use of liraglutide is associated with a mean weight loss of 0.2 to 3.2 kg relative to baseline and 0.1 to 2.6 kg relative to placebo. Liraglutiderelated hypoglycemia is generally mild, but its incidence and severity substantially increase in conjunction with sulfonylureas. Gastrointestinal adverse effects such as nausea, diarrhea, or vomiting occurred in 44% to 56% of patients who received liraglutide versus 17% to 19% with placebo. Premature withdrawal from trials occurred in 4% to 15% of liraglutide-treated patients (mainly attributable to gastrointestinal adverse effects), in comparison with 3% to 5% of those receiving placebo. Conclusion The 2 main advantages of liraglutide are mild degrees of weight loss and hypoglycemia. Important limitations, however, are the frequent occurrence of gastrointestinal adverse effects, the requirement of subcutaneous injection once daily, and the lack of long-term efficacy and safety data. Liraglutide may be a useful add-on therapy in patients with type 2 diabetes uncontrolled with metformin, when hypoglycemia, weight gain, or both are major concerns. (Endocr Pract. 2010;16:1028-1037)
Modeling and Testing a Cold Plate

The objectives of this work were to build and test a liquidcooled cold plate, and then to develop a numerical model to describe the thermal characteristics of the cold plate. An important parameter of interest was the total thermal resistance of the cold plate which is defined as the maximum temperature difference divided by the net heat flow rate. A cold plate was constructed by machining nine parallel, rectangular channels into an aluminum base (1.65 cm × 7.6 cm × 40 cm) upon which an aluminum cover plate was then welded. Twelve thermocouples were used to measure the temperature of the plate (surface and fin tip) and the circulating fluid at the inlet, outlet, and mid-plane. The working fluid was a 50/50 ethylene glycol-water mixture. Three heater blocks were mounted to the cold plate, and the assembly was insulated so that heat loss to the surroundings was minimized. Four runs were performed with flow rates ranging from 56 g/s to 95 g/s, and after steady-state conditions were reached the temperatures were recorded. Using these temperature measurements, the total thermal resistance was calculated. The thermal resistance of the cold plate was also calculated using a one-dimensional numerical model; agreement between the experimental measurements and model predictions is good. The methods described and results presented in this paper are useful to applied thermal engineers.Copyright © 2006 by ASME
Window Exchange Umbrella Sampling to Enhance Conformational Sampling and Quantify Energetics in Transmembrane Helix Assembly

The method of window exchange umbrella sampling molecular dynamics (WEUSMD) with a pre-optimized parameter set was recently used to obtain the most probable conformations and the energetics of transmembrane (TM) helix assembly of a generic TM sequence. When applied to glycophorin A TM domain (GpA-TM) using the window potentials along the helix-helix distance, however, tight interfacial packing of GpA-TM resulted in insufficient conformational sampling at short helix-helix separation. To address this sampling issue, we approached in two directions: (i) Extension of WEUSMD into two dimensions with the restraint potentials along the rHH and crossing angle (Ω) to bypass barriers for hidden variables; (ii) Design of another scheme for the window spacing rather than a uniform one to control the average acceptance probability (Pa) between neighboring windows systematically. The two-dimensional WEUSMD results demonstrate that the incomplete sampling in the one-dimensional WEUSMD arises from high barriers along the crossing angle between the GpA-TM helices. In principle, the multi-dimensional WEUSMD is suitable for modeling TM helix assembly. However, for three or higher dimensions, this approach becomes prohibitively intensive. To avoid this issue, one may consider the latter approach, the variable window spacing for WEUSMD, where the (highest) restraint force constant for the window at the shortest rHH geometrically decreases with rHH and the first passage time optimized parameter set is estimated by using an analytic approximation of Pa in general case (different window force constants for the exchange pairs). To demonstrate the improved sampling power of WEUSMD that in turn provides trustworthy potential of mean force, we applied WEUSMD with variable window spacing for the assembly of GpA-TM, and indeed obtained the improved sampling power compared to that with uniform window spacing.
Urban foraging and the relational ecologies of belonging

Through a discussion of urban foraging in Seattle, Washington, USA, we examine how people's plant and mushroom harvesting practices in cities are linked to relationships with species, spaces, and ecologies. Bringing a relational approach to political ecology, we discuss the ways that these particular nature–society relationships are formed, legitimated, and mobilized in discursive and material ways in urban ecosystems. Engaging closely with and as foragers, we develop an ethnographically grounded ‘relational ecologies of belonging’ framework to conceptualize and examine three constituent themes: cultural belonging and identity, belonging and place, and belonging and more-than-human agency. Through this case study, we show the complex ways that urban foraging is underpinned by interconnected and multiple notions of identity, place, mobility, and agency for both humans and more-than-human interlocutors. The focus on relational ecologies of belonging illuminates important challenges for environmental managem...
Combo viscoplasticity: An introduction with incremental formulation

Abstract Combo-viscoplastic models are phenomological representations of materials exhibiting viscoelastic and elastoplastic behavior. As the name suggests, combo models are formed by using viscoelastic and elastoplastic models as “building blocks” and combining them in a mechanical fashion. A variety of models are possible depending on the arrangement of the building blocks. No new material parameters are introduced. Some attributes of combo models are; (1) flexibility to simulate observed material behavior over a wide range of loading, (2) satisfaction of energy requirements (isothermal assumed), (3) feasible techniques of parameter identification, (4) readily adaptable to general numerical analysis programs. Incremental formulations are developed separately for linear viscoelasticity and elastoplacity and then used to synthesize two basic combo models: viscoelastic/elastoplastic and viscoelastic-plastic. In addition, a finite algorithm is presented to demonstrate how to incorporate the combo-models in a step-by-step solution strategy. Simple results are presented comparing combo-models with experimental creep data for acrylic plastic and sea ice.
Dimensional Regularization and Finite Calculations in Gauge Theories

Abstract The Leading finite corrections to a lowest order relationship between renormalized coupling constants in an SU(2) × U(1) gauge model of weak and electromagnetic interactions are presented. The calculations were carried out in two different gauge invariant dimensional regularization schemes. A brief outline and comparison of the technical aspects of these methods is given. For our particular calculation we find that both yield the same finite results as expected.
Proton pump inhibitors and bone fractures

The objective of this study was to critically assess studies regarding proton pump inhibitors (PPIs) and fractures. A MEDLINE search was conducted to identify relevant articles. Three case-control studies assessed fractures and PPI use. A study of all subjects with fracture in Denmark in 2000 revealed adjusted OR=1.18 (1.12-1.43) for PPI use within the last year (hip fracture OR=1.45,1.28-1.65); no dose-response relationship was identified. A study of hip fractures in UK patients > or =50 years found adjusted OR=1.44 (1.30-1.59) for >1 year of PPIs; duration and average daily dose were significantly associated with fracture risk: adjusted OR for >1.75 times average daily dose for >1 year was 2.65 (1.80-3.90). A study of vertebral, wrist, and hip fractures in Manitoba patients > or =50 years found adjusted OR=0.99 (0.90-1.11) for > or =1 year of continuous PPI; association became significant > or =7 years (OR=1.92, 1.16-3.18). Consistency of some positive results in all studies, the dose and/or duration response in two studies, the possibility that acid inhibition may decrease calcium absorption, and association with histamine(2)-receptor antagonists in some studies support a causal association. The low magnitude of the association (ORs<2), lack of dose-response in one study, lack of association with histamine(2)-receptor antagonists in one study, lack of experimental evidence documenting a mechanism, and inability to assess potential confounding factors limit statements regarding causality. As with all medications, PPIs should be used for appropriate indications and not in higher doses or longer durations than necessary to achieve the desired outcomes.
Analytical model for adhesively bonded composite panel-flange joints based on the Timoshenko beam theory

Abstract An analytical model for adhesively bonded composite panel-flange joints is developed using the kinematic relations of the Timoshenko beam theory and the constitutive equations in linear elasticity. The governing equations are derived for the normal and shear stresses in the adhesive layer of a composite joint containing two symmetric or unsymmetric laminates (as adherends) with equal- or unequal-thickness. For a composite joint with two equal-thickness symmetric adherends, closed-form solutions are obtained for the normal and shear stresses in the adhesive layer. Due to the consideration of the transverse shear effect in the current model, the solution for the normal (peel) stress derived here is different from that provided in an existing model using the Bernoulli–Euler beam theory-based classical laminate theory, even though the solution for the shear stress obtained here is the same as that given in the latter. The new model is quantitatively illustrated and compared with the existing model for two sample cases of composite panel-flange joints. The numerical results reveal that the peel stress for the joint under pure bending is tensile over the entire length of the adhesive and its values near the two ends of the adhesive are significantly larger than those predicted by the existing Bernoulli–Euler beam theory-based model.
Rod-and-frame performance and calculating ability: a replication.

In an earlier study using a timed serial sevens subtraction task ( 2 ) , it was shown that subjects with extremely high rod-and-frame scores made significantly more errors and took significantly more time to complete their calculations than did subjects who earned low or middle numbers of errors on the rod-and-frame. The present study replicates these findings with a timed serial threes addition task. Fifty right-handed psychiatric inpatients, aged 18 to 55 yr. (average education: 12 yr.) , were administered a timed serial threes addition task and the rod-and-frame. Patients with neurological diagnoses or history of alcoholism or electroconvulsive therapy were excluded. Written consent was obtained from all participants. The rod-and-frame and serial threes were administered by two different examiners, each unaware of the subject's performance on the task administered by the other. Rod-and-frame apparatus and procedures were as described elsewhere ( 1 ) . The serial threes required the subject to count forward as quickly as possible beginning with one and adding by threes, an individual's score being either number of errors or total performance time. Rod-and-frame scores (average deviations from 0" over eight trials) ranged from .875" to 35.5". The 50 subjects were divided into the lowest ( M = 1.86, S D = .62), middle ( M = 15.26, S D = 3.42), and highest ( M = 28.51, S D = 3.94) 20% of rodand-frame error scores. Subjects in these three groups did not differ significantly from one another in terms of age, education level, or socioeconomic status. Compared with both subjects having low and middle numbers of errors on the rod-and-frame, the subjects with most errors made significantly more errors ( F z . 3 = 5.88, P < .01) and took significantly longer times (F2.n = 5.81, P < .01) co complete the calculation task. Rod-and-frame groups with medium and low errors did not differ from one another in either errors ( t = .46) or time ( t = .53) . These findings are analogous to those earlier reported using a serial sevens subtraction task ( 2 ) . They provide additional demonstration of the close relationship between calculating ability and performance on the rod-and-frame.
Overview on the prevalence and impact of migraine

Migraine is a highly prevalent headache disorder that has a substantial impact on the individual and society. Over the past decade, substantial advances in research have increased understanding of the pathophysiology, diagnosis, epidemiology, and treatment of the disorder. This article reviews the burden of migraine, emphasizing the population-based studies that used standardized diagnostic criteria.
Simultaneous multi-channel data acquisition with variable sampling frequencies using a scalable adaptive synchronous controller

In this paper, a novel simultaneous multi-channel data acquisition system is proposed. Analog signals with different bandwidths are applied to an analog multiplexer with a single analog to digital converter. A novel scalable adaptive controller is designed to detect different bandwidths in order to determine the proper sampling rate for each input signal. The analog multiplexer is adaptively controlled to switch between the analog signals of variable bandwidths. The target technology of implementing the proposed design is the Field Programmable Gate Array (FPGA). The Analog-to-Digital Converter interface and the adaptive controller are implemented in the FPGA using hardware description language. The synthesized prototype used only 11% of the total logic elements (of Altera Cyclone II, EP2C35F672C-6N FPGA) and 15% of its total memory bits. The worst-case prorogation delay observed for the system is 12.04 ns, which is less than the 50 MHz clock period of 20ns. The Cyclone-II FPGA consumes power as low as 12 mW. The proposed system can be used in various applications that require heterogeneous multi-channel data acquisition system such as biomedical engineering.
Protein synthesis in isolated nuclei from adult rat brain.

— Nuclei from adult rat brains isolated with isotonic sucrose were incubated with [3H]leucine and later purified by centrifugation through hypertonic sucrose solutions. It was found that under these conditions, tritiated leucine was incorporated into TCA precipitable material. Protein synthesis was impaired if the nuclei were treated with the nonionic detergent Triton X-100 or hypertonic sucrose. The presence of puromycin or cycloheximide markedly inhibited the incorporation of the radioactive amino acid. Actinomycin D and RNase did not have any effect on the incorporation. Autoradiography indicated the presence of labelled material within the nuclei and not in cytoplasmic contaminants. Glial nuclei were more actively involved in protein synthesis than neuronal nuclei.
Characterization of RNase R-digested cellular RNA source that consists of lariat and circular RNAs from pre-mRNA splicing

Besides linear RNAs, pre-mRNA splicing generates three forms of RNAs: lariat introns, Y-structure introns from trans-splicing, and circular exons through exon skipping. To study the persistence of excised introns in total cellular RNA, we used three Escherichia coli 3 0 to 5 0 exoribonucleases. Ribonuclease R (RNase R) thoroughly degrades the abundant linear RNAs and the Y-structure RNA, while preserving the loop portion of a lariat RNA. Ribonuclease II (RNase II) and polynucleotide phosphorylase (PNPase) also preserve the lariat loop, but are less efficient in degrading linear RNAs. RNase R digestion of the total RNA from human skeletal muscle generates an RNA pool consisting of lariat and circular RNAs. RT–PCR across the branch sites confirmed lariat RNAs and circular RNAs in the pool generated by constitutive and alternative splicing of the dystrophin pre-mRNA. Our results indicate that RNase R treatment can be used to construct an intronic cDNA library, in which majority of the intron lariats are represented. The highly specific activity of RNase R implies its ability to screen for rare intragenic transsplicing in any target gene with a large background of cis-splicing. Further analysis of the intronic RNA pool from a specific tissue or cell will provide insights into the global profile of alternative splicing.
Mutagenic potential of sediments from the Grand Calumet River

The Grand Calumet River/Indiana Harbor Canal is one of the International Joint Commission's Great Lakes Areas of Concern (AOC). Like many other AOCs, the Grand Calumet River is in a heavily industrialized area and has a history of chemical contamination. Many of the chemicals found in the industrial and municipal wastes that enter the waterway end up in sediment where they are concentrated to high levels. In order to assess the potential genotoxicity of sediments from the Grand Calumet River, the authors determined the mutagenic potential of organic extracts of sediments. The sediment extracts were assayed in the Salmonella/microsome mutagenicity test. In the Ames test, all ten sediment samples assayed were found to be mutagenic. In general, chemicals found in the sediments required metabolic activation before a positive mutagenic response was observed.
Scale invariance rule in electromagnetic scattering

The volume integral equation formalism is used to prove the scale invariance rule for an arbitrarily sized scatterer with an arbitrary shape, morphology, and orientation. The only assumptions are that the scatterer is made of optically isotropic linear materials and is embedded in a homogeneous, linear, isotropic, and nonabsorbing infinite medium. Published by Elsevier Ltd.
Reinterpretation of oxygen on Al samples by variable-energy positrons

When low-energy positrons are implanted into crystals and diffuse back to the crystal surface, they can form positronium by escaping from the crystal. This positronium formation fraction is a function of temperature for an aluminum sample coated with oxygen. Lynn observed large differences in this positronium fraction in the heating and cooling curves and attributed the hysteretic behavior to the oxygen on the aluminum surface undergoing a phase transition from an amorphous to a crystalline state. This Brief Report offers an alternative explanation for the hysteretic behavior of the positronium formation fraction, namely, the oxygen leaves the surface region either by desorption or by migration into the bulk Al crystal.
Photooxidation of 2-methyl-3-Buten-2-ol (MBO) as a potential source of secondary organic aerosol.

2-Methyl-3-buten-2-ol (MBO) is an important biogenic hydrocarbon emitted in large quantities by pine forests. Atmospheric photooxidation of MBO is known to lead to oxygenated compounds, such as glycolaldehyde, which is the precursor to glyoxal. Recent studies have shown that the reactive uptake of glyoxal onto aqueous particles can lead to formation of secondary organic aerosol (SOA). In this work, MBO photooxidation under high- and low-NOx conditions was performed in dual laboratory chambers to quantify the yield of glyoxal and investigate the potential for SOA formation. The yields of glycolaldehyde and 2-hydroxy-2-methylpropanal (HMPR), fragmentation products of MBO photooxidation, were observed to be lower at lower NOx concentrations. Overall, the glyoxal yield from MBO photooxidation was 25% under high-NOx and 4% under low-NOx conditions. In the presence of wet ammonium sulfate seed and under high-NOx conditions, glyoxal uptake and SOA formation were not observed conclusively, due to relatively low (...
COMPARATIVE RISK ASSESSMENT : WHERE DOES THE PUBLIC FIT IN ?

Comparative risk assessment (CRA) is playing an ever-increasing role in environmental policy priority setting, as manifested in national and numerous subnational comparative risk projects. It is widely accepted that public values, interests, and concerns should play an important role in CRA. However, the philosophical basis for public involvement in CRA has not been adequately explored, nor have comparative risk projects always made explicit their rationales for public involvement. The author examines the political, normative, and epistemic rationales for public involvement and explores the case for public involvement in the making of ethical, valuation, and evidentiary judgments. The author considers key issues each rationale raises, problems eachfaces, and some of the implications of each for specific aspects of CRA.
The GABA-glutamate connection in schizophrenia : Which is the proximate cause?

Schizophrenia is a chronic, disabling psychiatric disorder that genetic studies have shown to be highly heritable. Although the dopamine hypothesis has dominated the thinking about the cause of schizophrenia for 40 years, post-mortem and genetic studies have provided little support for it. Rather, post-mortem studies point to hypofunction of subsets of GABAergic interneurons in the prefrontal cortex and the hippocampus. Furthermore, clinical pharmacologic, post-mortem and genetic studies have provided compelling evidence of hypofunction of a subpopulation of NMDA receptors in schizophrenia. In support of this inference, agents that directly or indirectly activate the glycine modulatory site on the NMDA receptor (the Glycine B receptor) reduce symptoms in chronic schizophrenia, especially negative symptoms and cognitive impairments. Electrophysiologic and pharmacologic studies suggest that the vulnerable NMDA receptors in schizophrenia may be concentrated on cortico-limbic GABAergic interneurons, thereby linking these two neuropathologic features of the disorder.
Activation of the Mitogen-activated Protein Kinase Pathway by fMet-Leu-Phe in the Absence of Lyn and Tyrosine Phosphorylation of SHC in Transfected Cells

The chemotactic peptide f-Met-Leu-Phe (fMLP) stimulates leukocyte functions through binding and activation of a specific G-protein-coupled formyl peptide receptor (FPR). Recent studies have shown that stimulation of neutrophils with fMLP induces the activation of two members of the mitogen-activated protein kinase (MAP kinase) family, ERK1 and ERK2, through mechanisms that are not completely understood but may involve the phosphorylation of the adapter protein SHC by the Src-related kinase Lyn. In this study, transfected fibroblasts expressing the rabbit FPR were used to investigate further the role of Lyn and SHC phosphorylation in fMLP-stimulated MAP kinase activation. Stimulation of transfected cells with fMLP resulted in the time- and dose-dependent increase in tyrosine phosphorylation and activation of ERK1 and ERK2 and the activation of MEK, the MAP kinase/ERK kinase. The activation of both ERKs and MEK was inhibited by preincubation of the cells with pertussis toxin, indicating that activation was dependent upon a Gi/Go-like protein that couples to the receptor. Our data also show that, unlike neutrophils, FPR-transfected fibroblasts do not express the Src-related kinase Lyn. In the absence of Lyn, fMLP stimulation did not result in an increased tyrosine phosphorylation of the adapter protein SHC, whereas it was still able to induce MAP kinase activation. These data suggest that Lyn and SHC are not the only upstream signals for activation of the MAP kinase/ERK pathway by fMLP and demonstrate the potential application of the FPR-transfected cells for the delineation of additional signaling mechanisms stimulated by fMLP.
Using Technology to Enhance Relationships in Interactive Television Classrooms

Abstract Moorhead State University offered an MBA class in the fall semester of 1997, using interactive television (ITV). Three separate classrooms were used. Fourteen students were at two remote classroom sites, and 10 students were in the campus classroom with the instructor. We describe our experiences and findings in delivering a graduate-level course using ITV in combination with a class homepage and e-mail.
Wettability of transition metal oxide surfaces

Abstract The wettability of transition metal oxide surfaces (TiO 2 , ZrO 2 and HfO 2 ) by water was investigated by measuring the contact angles using the sessile drop method. The oxide surfaces were prepared by thermal oxidation of polished metal foils of Ti, Zr and Hf, which had been polished to different levels of surface roughness. The surfaces were also characterized by optical microscopy, X-ray diffraction (XRD), atomic force microscopy (AFM) and Auger/XPS (AES/ESCA) methods. From the dependence of contact angles on surface roughness for the three investigated oxides, contact angles on flat surfaces were calculated as 70.7°, 59.9° and 74.0° for TiO 2 , ZrO 2 and HfO 2 , respectively. These results suggest that the three oxides do not provide acceptable waterproofing coatings on silica fibers used for space shuttle thermal insulation.
Free fascia lata repair for a second recurrent congenital diaphragmatic hernia

Repair of recurrent congenital diaphragmatic hernia (CDH) continues to be a difficult problem. Although several materials have been used to repair recurrent CDH, the ideal material has yet to be established. We report the successful use of an autologous free fascia lata graft to repair the diaphragm following a second recurrence of CHD. The fascia lata is one of the strongest fascia in the body and is easy to obtain without extremity functional loss even in children. This procedure is regarded as effective for the repair of recurrent CDH.
Adsorption of a Cationic Polyacrylamide onto the Surface of a Nafion Ionomer Membrane

Time-dependent adsorption of a high-molecular-weight cationic polyacrylamide (acrylamide/β-methacryloxyethyltrimethylammonium methyl sulfate copolymer) from sulfuric acid solution onto a perfluorosulfonate ionomer (Nafion) membrane was characterized using X-ray photoelectron spectroscopy (XPS), ultraviolet/visible spectroscopy (UV/vis), and dynamic contact angle measurements in water. Flourine and nitrogen atomic surface concentrations determined from XPS were well correlated to the adsorbed polymer surface coverage from water contact angle analysis via the Cassie relationship and the adsorbed polymer concentration from UV/vis, respectively. Cationic polyacrylamide surface coverage remained constant at about 60% for all immersion times investigated. On the other hand, the adsorbed polymer concentration increased with immersion time, approaching a plateau after about 9 min. Such behavior was attributed to the transition from an expanded, two-dimensional, adsorbed polymer chain configuration at early times ...
Facts, lies, and videotapes: the permanent vegetative state and the sad case of Terri Schiavo.

Right to die legal cases in the United States have evolved over the last 25 years, beginning with the Karen Quinlan case in 1975. Different substantive and procedural issues have been raised in these cases, and society's thinking has changed as a result of the far more complex legal issues that appear today as opposed to the simplistic views raised in early landmark cases. Many of the early cases involved patients in a vegetative state, but more recently patients who were in a minimally conscious state have been the center of attention. Early cases involved the withdrawal of respirators and other sophisticated technology, but later cases centered on the withdrawal of artificial nutrition and hydration, and even whether it was permissible for competent patients to stop eating and drinking in a normal manner. Initial cases pitted families who argued for withdrawal of treatment, usually against the attending physicians and hospitals and/or the state or federal government, who argued for continuation of treatment.
Disposition and Biological Activity of Benzo[a]pyrene-7,8-dione. A Genotoxic Metabolite Generated by Dihydrodiol Dehydrogenase†,‡

A novel pathway of polycyclic aromatic hydrocarbon metabolism involves the oxidation of non-K-region trans-dihydrodiols to yield o-quinones, a reaction catalyzed by dihydrodiol dehydrogenase (DD). We have recently shown that in isolated rat hepatocytes (±)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP-diol) was oxidized by this route to yield benzo[a]pyrene-7,8-dione (BPQ). We now report the disposition of BPQ and its mutagenic and genotoxic properties. Using [3H]BPQ it was found that 30% of the radioactivity was sequestered by rat hepatocytes into the cell pellet. Isolation of hepatocyte DNA provided evidence for a low level of covalent incorporation of BPQ into DNA (30 ± 17 adducts/106 base pairs). Examination of the hepatocellular DNA by agarose gel electrophoresis following treatment with BPQ indicated that extensive fragmentation had occurred. DNA fragmentation was also observed when hepatocytes were treated with BP-diol and this effect was attenuated by indomethacin, a DD inhibitor. Hepatocytes ...
US general population norms for telephone administration of the SF-36v2

Objective US general population norms for mail administration of the Medical Outcomes Study 36-Item Short Form Version 2 (SF-36v2) were established in 1998. This article reports SF-36v2 telephone-administered norms collected in 2005–2006 for adults aged 35–89 years.
Attenuation and Dispersion Characteristics of Various Plastics in the Frequency Range 1-10 MHz

It is observed experimentally that PMMA, phenolic and various polyester resins exhibit little dispersion but significant frequency-dependent attenuation for dilatational waves in the frequency range 1-10 MHz. It is also shown that the shape of a low amplitude stress pulse propagating through a material with the above characteristics becomes significantly altered after propagating only a few cm. Thus the stress pulse distortion observed in plastic matrix-type composite materials may not be attributed to geometrical dispersion and attenuation alone; material attenuation in the matrix must be considered. The representation of these plastics by a standard linear viscoelastic solid is shown to provide an adequate model of the experimental data for the stated frequency range.
Occam paradox? A variation of tapia syndrome and an unreported complication of guidewire-assisted pedicle screw insertion.

Study Design Case report. Clinical Question The clinical aim is to report on a previously unknown association between guidewire-assisted pedicle screw insertion and neuropraxia of the recurrent laryngeal nerve (RLN), and how this may overlap with the signs of Tapia syndrome; we also report our approach to the clinical management of this patient. Methods A 17-year-old male patient with idiopathic scoliosis experienced Tapia syndrome after posterior instrumentation and arthrodesis at the level of T1–L1. After extubation, the patient had a hoarse voice and difficulty in swallowing. Imaging showed a breach in the cortex of the anterior body of T1 corresponding to the RLN on the right. Results Otolaryngological examination noted right vocal fold immobility, decreased sensation of the endolarynx, and pooling of secretions on flexible laryngoscopy that indicated right-sided cranial nerve X injury and left-sided tongue deviation. Aspiration during a modified barium swallow prompted insertion of a percutaneous endoscopic gastrostomy tube before the patient was sent home. On postoperative day 20, a barium swallow demonstrated reduced aspiration, and the patient reported complete resolution of symptoms. The feeding tube was removed, and the patient resumed a normal diet 1 month later. Tapia syndrome, or persistent unilateral laryngeal and hypoglossal paralysis, is an uncommon neuropraxia, which has previously not been observed in association with a breached vertebral body at T1 along the course of the RLN. Conclusion Tapia syndrome should be a differential diagnostic consideration whenever these symptoms persist postoperatively and spine surgeons should be aware of this as a potential complication of guidewires in spinal instrumentation.
Bounds and Approximations for the Transportation Problem of Linear Programming and Other Scalable Network Problems

Bounds and approximate formulae are developed for the average optimum distance of the transportation linear programming (TLP) problem with homogeneously, but randomly distributed points and demands in a region of arbitrary shape. It is shown that if the region size grows with a fixed density of points, then the cost per item is bounded from above in 3 + dimensions (3 +-D), but not in 1-D and 2-D. Lower bounds are also developed, based on a mild monotonicity conjecture. Computer simulations confirm the conjecture and yield approximate formulae. These formulae turn out to have the same functional form as the upper bounds. Curiously, the monotonicity conjecture implies that the cost per item does not depend on zone shape asymptotically, as problem size increases, for 2 +-D problems but it does in 1-D. Therefore, the 2-D case can be viewed as a transition case that shares some of the properties of 1-D (unbounded cost) and some of the properties of 3-D (shape independence).The results are then extended to more general network models with subadditive link costs. It is found that if the cost functions have economies of scale, then the cost per item is bounded in 2-D. This explains the prevalence of the "last mile" effect in many logistics applications. The paper also discusses how the results were used to estimate costs under uncertainty for a vehicle repositioning problem.
Neutron irradiation of Cu-Al at elevated temperatures

Abstract The effect of neutron irradiation at elevated temperatures on the electrical resistivity of Cu-Al (15 at. % Al) is described. The results support the idea that at temperatures below 200°C the alloy is in a metastable state. Upon irradiation atomic mobilities are enhanced and the metastability is eliminated, accompanied by a decrease in resistivity. An analysis is made of the temperature dependence of the rate of the atomic rearrangement stimulated by the irradiation. It is found that the activation energy for motion remains constant during the process at about 0.5 eV. A comparison is made with the results of a previous experiment in which the alloy was irradiated at lower temperatures.
Field Correctors for Large Telescopes

The aberrations of large telescope mirrors can be corrected by lens systems located near to the focal plane. The three-element systems, designed by Ross for the 200-in. (5-m) Mount Palomar telescope, are shown to be amenable to a higher degree of aberration correction, and designs of this form are given, adapted for use at the focus of the primary mirror of a Ritchey–Chretien telescope. A different form of three-component system gives still better aberration correction, and examples of this are given, suitable for use on the Kitt Peak projected 150-in. (3.8-m) f/2.8 telescope. Simple two-element systems to correct the field aberrations at the focus of the two-mirror Ritchey–Chretien telescope are also described.
A new approach to the modeling of pnpn structures

Abstract An approach for the derivation of stationary voltage-current characteristics of pnpn-structures is presented. In contrast to the classical method of the two-transistor analog, the van Roosbroeck system is considered throughout the device. The problem is simplified by using the methods of asymptotic analysis: a suitable normalisation leads to the identification of small dimensionless parameters which are used in a formal perturbation procedure. Neglecting these small parameters is equivalent to making certain simplifying assumptions such as charge neutrality, depletion or low injection. The approximate problems are in general much easier to solve than the full van Roosbroeck system. The main results are explicit formulae for the stationary voltage-current characteristic for moderate currents, expressions for the holding current and the statement that, in the absence of impact ionisation, the breakover voltage can be explained by finite domain effects.
The speculative attack on the peso and the real exchange rate: Argentina, 1979–1981

Abstract This article applies a speculative attack model to Argentina during its pre-announced exchange-rate system from January 1, 1979 to June 30, 1981. The model attempts to verify a rule whereby if domestic credit growth exceeds the rate of currency depreciation, two things occur: First, the domestic price of non-traded goods rises relative to the price of traded goods. Second, foreign reserves decline until a point when a sudden speculative attack depletes remaining reserves, causes a precipitous fall in the relative price of non-tradables, and forces the country onto a floating exchange-rate regime. In some important respects, the model captures the Argentinian experience, yet in other respects if fails to do so.
Transfer of the Kenyan Kikuyu male circumcision ritual to future generations living in the United States

This phenomenological research report from analysis of interviews with 18 participants focuses on the theme of transferring an age-old initiation-into-manhood circumcision ritual to future generations of Kenyan Kikuyu who are living in the US. We identified three subthemes and found a strong indication that, while personally meaningful to the participants, the ritual, its meaning, and its impact likely will dwindle and possibly eventually be eradicated among future Kikuyu generations in America unless there is a concerted effort to shape the initiation rite into a form that they find meaningful.
Aortic valve replacement after previous coronary artery bypass grafting

Background. As the population ages, an increasing number of patients with previous coronary artery bypass grafting (CABG) will require subsequent aortic valve replacement (AVR). This study examined outcome of AVR after previous CABG and reviewed possible indications for valve replacement at the time of initial myocardial revascularization. Methods. Between March 1975 and December 1994, 145 patients had AVR after previous CABG. Sixty-three patients (43%) had their initial CABG elsewhere. Reoperation for AVR was the second cardiac procedure in 137 patients and the third in 8. Redo CABG with AVR was done in 66 (46%). There were 118 men and 27 women. The mean age at CABG was 64 ± 7.9 years; for AVR this was 71 ± 7.6 years. Results. In 2 young patients accelerated calcific aortic stenosis occurred in the setting of renal failure. Significant aortic stenosis did not appear to be addressed at initial CABG in 3 patients. Transaortic valvular gradient, as measured by cardiac catheterization, increased by 10.4 ± 7.0 mm Hg/y. Twenty-four patients (16.6%) died. The mortality for AVR alone or for AVR + redo-CABG was 15 of 125 patients (12%). For patients having more complicated procedures, the mortality was 9 of 20 (45%). Nine patients (6.2%) suffered a postoperative cerebrovascular accident. Low preoperative ejection fraction measured by echocardiography, sternal reentry problems, complexity of operation, and prolonged cross-clamp and bypass times were significant factors associated with mortality. Age at AVR, interval between operations, the extent of underlying native coronary artery disease, the state of the previously placed bypass conduits, and methods of myocardial preservation were not significant predictors of operative mortality. On multivariate analysis there was only one significant value: prolonged crossclamp time. Conclusions. Aortic valve replacement after previous CABG is associated with a mortality that is higher than that seen after repeat CABG or repeat AVR. It seems prudent, therefore, to use liberal criteria for AVR in those patients who require coronary revascularization and who, at the same time, have mild or moderate aortic valve disease.
Worker mobility, employer-provided general training, and the choice of graduate education☆

This paper links inherent mobility to observed schooling choices. A job search model with graduate education predicts that more mobile workers are more likely to enroll in full-time MBA programs. Adding to the literature on employer-sponsored general training, the model predicts that employers are likely to provide tuition assistance to workers who find quits costly. I use a panel survey of GMAT registrants to test some of the empirical implications of the model. I show that observable measures of job attachment are correlated with the probability of attending part-time and, conditional on part-time attendance, with the likelihood of receiving tuition reimbursement.
Abstract A70: PTEN loss induces selective upregulation of CXCL8 signaling to modulate survival and resistance to radiation

PTEN is a haplo-insufficient tumor suppressor and the most frequently mutated gene in prostate cancer (CaP). Moreover, loss of PTEN expression arising from allele deletion or promoter methylation is prevalent early disease. The objective of our study was to characterize how the genetic instability and/or stress-induced signaling arising from PTEN loss modulated the expression of clinically-relevant pro-inflammatory chemokines. Transient (siRNA) or prolonged (shRNA) repression of PTEN resulted in increased transcription-mediated increases in expression of CXCL8 and its receptors, CXCR1 and CXCR1 in DU145 and 22Rv1 cells. Stress-induced expression of CXCL8, CXCR1 and CXCR2 was greater in magnitude and duration in PTEN-null PC3 and LNCaP cells, in contrast to the dampened response observed in PTEN-expressing cells. PTEN had no effect on basal or stress-induced expression of CCL2, CXCL12 or their receptors in prostate cancer cells. Moroever, the efficacy of autocrine CXCL8 signaling to induce HIF-1 and NF-κB transcription was also greater in magnitude and duration in PTEN-null prostate cancer cells or following siRNA-mediated PTEN knockdown in DU145 and 22Rv1 cells. Consistent with in vitro data, we observed increased expression of the orthologous murine chemokine KC in atypical cytological features of PTEN+/− prostate tissue relative to normal epithelium in PTENWT glands. Finally, siRNA or shRNA-mediated attenuation of CXCL8 signaling selectively decreased the viability of CaP cells harboring partial or complete PTEN-loss. Furthermore, the knockdown of CXCL8 signaling potentiated the sensitivity of PTEN-depleted prostate cancer cells to clinicallyrelevant doses of ionozing radiation. We conclude that there is a selective upregulation of CXCL8 signaling in PTEN-deficient prostate epithelium, which contributes to the growth, survival and reduced therapeutic sensitivity of these cells. Citation Format: Jonathan Coulter, Pamela Maxwell, Melanie McKechnie, Jessica Neisen, Richard Kennedy, Manuel Salto-Tellez, Chris Albanese, David Waugh. PTEN loss induces selective upregulation of CXCL8 signaling to modulate survival and resistance to radiation [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr A70.
Effect of tissue norepinephrine depletion by 6-hydroxydopamine on blood pressure in spontaneously hypertensive rats

Abstract Blood pressure was studied in normotensive and spontaneously hypertensive rats (SHR) in which catecholamine depletion had been produced by 6-hydroxydopamine. After i.v. administration of 80–200 mg/kg 6-hydroxydopamine, norepinephrine (NE) levels in heart, spleen, and kidney were markedly reduced (14–66% of control value) while brain NE remained unchanged. These doses did not affect development of hypertension in SHR or the blood pressure in normotensive control rats during a 20 day period of study. A transient decrease of blood pressure was observed acutely (1–3 days) after an 80 mg/kg dose in normotensive and hypertensive animals. Depletion of NE in the brainstem (to 33–42% of control value) after intraventricular injection of 6-hydroxydopamine, 50–300 μg, had no effect on blood pressure of SHR and normotensive rats. It is concluded that only a small portion of tissue NE content is sufficient for development and maintenance of hypertension in the SHR.
PRESSURE NATRIURESIS IN EXPERIMENTAL GLOMERUIO NEPHRITIS

To examine possible adaptive mechanisms involved in the maintenance of glomerular filtration and sodium balance in glomerulonephritis, an in situ perfused kidney was compared in 7 normal mongrels (N) and in 6 mongrels 2 to 4 months following the production of mild anti glomerular basement membrane nephritis (GN). The left kidney was perfused via a carotid-renal artery pump at systemic pressure levels and then at an elevated pressure. The average mean systemic pressure was higher in GN (140 mm Hg) than in N (121 mm Hg). Filtration rates (GFR) and renal plasma flows (RPF) were similar, averaging 17.3 and 88 ml/min in GN and 18.6 and 70.3 ml/min in N. When perfusion pressure was elevated to 195 mm Hg mean sodium excretion more than doubled in GN and in N while GFR and RPF decreased by 30% in GN and remained constant in N. The data demonstrate that pressure natriuresis occurs in GN as well as in N and that the GN kidney responds to increased perfusion pressure with exaggerated vasoconstriction as compared to N which autoregulates. The excessive vasoconstrictor response of the GN kidney may be revealing an adaptive vaso-dilatation which occurs as a mechanism for the maintenance of renal perfusion and sodium homeostasis.
Grain-size effects in the indentation fracture of MgO

The variation of radial crack length with indentation load in a series of polycrystalline MgO materials is examined as a function of grain size. Comparison with the single-crystal response indicates that the fracture resistance of the polycrystals is significantly enhanced. Fracture surface observations suggest that the source of the enhancement is frictional interlocking of jogs in the crack plane caused by the tendency of the local crack path to maintain preferred crystalline cleavage planes. A model is developed for the fracture resistance increase and used to describe the radial crack lengths. The parameters thus derived suggest that a minimum grain size exists, below which this mechanism of fracture resistance is not operative.
Evoked splanchnic potentials produced by electrical stimulation of medullary vasomotor regions.

In decerebrate or urethane-anesthetized cats with pneumothorax and neuromuscular blockade, evoked responses in the efferent splanchnic nerve, elicited by electric shocks to medullary regions, were studied as samples of sympathetic outflow related to vasocontrictor activity and were analyzed with an average-response computer.