cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization of microsatellite markers for the tanoak tree, Lithocarpus densiflorus

We describe the development of 19 primers for amplification of microsatellite loci for tanoak, Lithocarpus densiflorus (Hook. & Arn.). A population from Soquel State Demonstration Forest, Santa Cruz County, California (n = 20), and eight individuals from four additional coastal populations and one interior (Sierra Nevada) population were used to investigate polymorphism. The total number of alleles per locus ranged from two to 10. Observed heterozygosity in the Soquel population ranged from 0.05 to 0.70, with two loci being fixed.
Increased Myocardial Dysfunction After Ischemia-Reperfusion in Mice Lacking Glucose-6-Phosphate Dehydrogenase

Background— Free radical injury contributes to cardiac dysfunction during ischemia-reperfusion. Detoxification of free radicals requires maintenance of reduced glutathione (GSH) by NADPH. The principal mechanism responsible for generating NADPH and maintaining GSH during periods of myocardial ischemia-reperfusion remains unknown. Glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme in the pentose phosphate pathway, generates NADPH in a reaction linked to the de novo production of ribose. We therefore hypothesized that G6PD is essential for maintaining GSH levels and protecting the heart during ischemia-reperfusion injury. Methods and Results— Susceptibility to myocardial ischemia-reperfusion injury was determined in Langendorff-perfused hearts isolated from wild-type mice (WT) and mice lacking G6PD (G6PDdef) (20% of WT myocardial G6PD activity). During global zero-flow ischemia, cardiac function was similar between WT and G6PDdef hearts. On reperfusion, however, cardiac relaxation and contra...
Development of parallel-plate avalanche counters for the detection of fission fragments

Abstract Parallel-plate avalanche counters for the detection of heavy ions, especially fission fragments, have been developed for use in in-beam experiments. Typical energy and time spectra obtained from a 252Cf source are shown and discussed. Also particle induced fission is studied by means of the nuclear reactions 235 U (α, f), 238 U ( p , f) and 235 U ( Li , f) . Energy spectra for F and S ions elastically scattered from a thin Au target are presented. The fabrication of the detectors is described in detail.
Correlation between random dense parking and random dense packing for determining particle coordination number in binary systems

An alternative method is proposed to estimate particle coordination number in a random packing of spheres. It is based on the correlation between random dense packing and random dense parking, where random dense parking is defined as the random placement of equal-size disks (or spheres) on a surface such that none overlap. Assuming that the limit for random dense parking (fraction of area covered by the projected area of particles) is independent of surface curvature, an analytical expression of the coordination number for spheres surrounding a central sphere of equal or different size is obtained. A similar analysis is achieved for a sphere touching a flat wall. Both expressions are tested through numerical simulations of bimodal, spherical particle systems.
Laryngeal mask airway for management of a difficult airway and extracorporeal shock wave lithotripsy

Summary We report successful use of the laryngeal mask airway (LMA) in an eight-year-old child with failure to thrive and a known difficult tracheal intubation for ESWL in a mobile lithotripter van.
The Impact of Election Day Registration on Voter Turnout and Election Outcomes

Voter registration is widely viewed as a barrier to voter participation in general, and especially so for likely Democratic voters. A popular remedy for both turnout effects is election day registr...
Foreign Workers and the Provision of Public Services: The Case of Kuwait

Seeks to provide some insight as to the scope for population policy in post‐war Kuwait, where officially the Government is committed to reducing the expatriate population. Specifically attempts to determine which public services were most likely to be responsive to increases in the foreign population. Were these services provided to both Arab and Asian workers alike or were the patterns of supply somewhat different by nationality? Did public services adjust quickly to increases in the foreign population or were the increased provisions spread out gradually over time? Mainly finds that, despite the early post‐liberation statements of Kuwaiti officials, it will not be possible to dispense entirely with foreign workers. There is a good chance, however, that the Government′s political policy of replacing Palestinian workers with those from Asia will provide the unintended benefit of considerable budgetary savings.
Multi-agent information classification using dynamic acquaintance lists

There has been considerable interest in recent years in providing automated information services, such as information classification, by means of a society of collaborative agents. These agents augment each other's knowledge structures (e.g., the vocabularies) and assist each other in providing efficient information services to a human user. However, when the number of agents present in the society increases, exhaustive communication and collaboration among agents result in a large communication overhead and increased delays in response time. This paper introduces a method to achieve selective interaction with a relatively small number of potentially useful agents, based on simple agent modeling and acquaintance lists. The key idea presented here is that the acquaintance list of an agent, representing a small number of other agents to be collaborated with, is dynamically adjusted. The best acquaintances are automatically discovered using a learning algorithm, based on the past history of collaboration. Experimental results are presented to demonstrate that such dynamically learned acquaintance lists can lead to high quality of classification, while significantly reducing the delay in response time.
A sharp interface isogeometric solution to the Stefan problem

Abstract In the present paper, the Stefan problem is solved by enriching an underlying NURBS-based isogeometric approximation with an explicitly defined (sharp) interface on which a hybrid function/derivative condition is isoparametrically described. Since the geometry of the enrichment is explicitly defined, normals and curvatures are explicitly computed at any point on the interface. Thus, the enriched approximation naturally captures the interfacial discontinuity in temperature gradient and naturally enables the imposition of Gibbs–Thomson condition. The blending of the enrichment with the underlying approximation requires an estimate of distance to the enriching geometry from a quadrature point and the parametric value of the footpoint on the enriching geometry. These quantities are computed efficiently in the present paper using an algebraic estimate of distance coupled with an algebraic point projection method. These algebraic schemes rely on implicitization of the parametric curve, and are shown to be more efficient and robust than Newton–Raphson iterations. Procedures for adaptive time stepping, refinement and coarsening of geometry are developed to increase the stability and efficiency of the developed methodology. Several numerical examples of classical and dendritic Stefan problem are presented to demonstrate the methodology.
SU-E-I-110: Do Reconstruction Parameters Affect CT-Based Kidney Stone Volume Quantification?

Purpose: To investigate the effects of reconstruction field‐of‐view (FOV), slice increment and kernel on the quantification of kidney stone volume. Methods: Three concentrations (200, 400 and 800 mg/cc) and two sizes (21.87 and 99.9 mm3) of hydroxyapatite (HA: Ca5(PO4)OH) cylinders were used to simulate kidney stones of 3 and 5 mm diameter, respectively). These were submerged in a 30 cm wide water phantom and scanned on a dual‐ source CT scanner operating in dual‐energy mode. Reconstruction was performed with a) FOVs from 50 to 300 mm at 50 mm interval; b) image reconstruction increments of 0.1, 0.3 and 0.6 mm; c) 6 recon kernels, from very smooth to medium sharp, all using a 0.6 mm image thickness. CT data were segmented and volumes calculated using volume‐rendered 3D images of each stone, commercial software(Analyze, version10.0) and fixed CT number thresholds (130, 250 and 550 HU for HA200, HA400 and HA800, respectively). Differences in volume between measured and reference values, normalized to the reference values were calculated. The range (maximum — minimum) in normalized volume differences were used to assess the overall influence of various reconstruction parameters. Results: Although normalized volume differences varied with cylinder concentration and size, the differences among FOVs were not substantial (<10.61%). The normalized volume differences among image increments were very small (< 2.45%), except for the lowest concentration/smallest size (differences up to 8.14%), where the smallest image increment was most accurate (differences < 3.02%). Very smooth kernels decreased volume accuracy by as much as 16.19%. Conclusions: Reducing reconstruction FOV did not increase accuracy of volume measurements. Overlap between reconstructed images was beneficial for volume measurement of low concentrations of HA (200 mg/cc) and small size (3 mm diameter) objects. Very smooth kernels were not suitable for volume measurement due to too much edge blurring.
The influence of molecular weight distribution on some properties of polystyrene melt

The viscosities of a number of monodisperse polystyrene melts have been measured using a capillary rheometer. The materials covered a molecular weight range of 43,000–460,000. Shear rates of 1.54–1540 sec.−1 and temperatures of 350–450°F. were studied. The effect of molecular weight distribution of polydisperse polystyrene was also measured. It was found that while low shear viscosity was dependent on Mw, higher shear melt viscosities depended on averages between Mw and Mn until at 1000–2000 sec.−1, Mn controlled viscosity. Agreement with the 3.4-power dependence of zero shear viscosity was good. Similar exponential relationships were found, with higher rates of shear, corresponding to smaller values of the exponent. Constant values of the exponent were found at constant shear stress but not at constant shear rate. Agreement with the constancy of the activation energy for viscous flow for various molecular weights and distributions at constant shear stress was good. However at constant shear rate, ΔE decreased as the molecular weight average increased and as the distribution broadened. Viscosity versus shear rate master curves were constructed by using the Buehe-Harding procedure. All monodisperse polystyrenes showed excellent fit with the master curve. Other molecular weight distributions did not. Master curves also were constructed for measurements of dynamic viscosity versus frequency for monodisperse polystyrene. These curves when compared to steady state viscosities failed to confirm the correspondence of ηa to either |η*| or to η′.
Effect of bumetanide on the positive endocochlear dc potential of the cat.

Abstract Twenty-seven cats were recorded from the scala media of the cochlea in order to evaluate the reduction in the positive endocochlear dc potential (EP) produced by iv bumetanide and to compare these changes to the bumetanide-induced N1 depression observed previously. A linear relationship does exist between the dose of bumetanide administered and the resultant mV reduction of the EP. The equation for the regression line of this dose-response to bumetanide is y (maximal reduction of EP) = 259.5 + 92.8 × (log mmol/kg iv bumetanide). The maximal reduction of EP occurring within 1 min after the larger doses of bumetanide correlates well with changes in N1 previously observed after similar doses. When multiple linear regression analysis is performed, the amount of N1 depression produced by a particular dose of bumetanide is found to be linearly related to the amount of EP reduction produced by that dose of bumetanide. These data indicate that the acute ototoxicity produced by this “loop” diuretic is due to its effect on EP.
Revised type locality of the Whiskered Auklet Aethia pygmaea (Aves: Alcidae)

Abstract The accepted type locality of the Whiskered Auklet Aethia pygmaea, St. Matthew Island, is considered to be erroneous because it lies far outside of the bird's geographic range. The species was founded on the description of a now-lost immature specimen taken on the third voyage of James Cook, and the locality was probably a misattribution due to a simple transcription error. We here designate as revised type locality ‘Unalaska Island, Aleutian Islands, Alaska,’ a place known to have been visited on Cook's third voyage where and at a time when immature birds would have been present.
Opening the ivory tower's door: An analysis of the determinants of the formation of U.S. university spin-off companies

This paper presents findings from an analysis of the determinants of the formation of university spin-off companies within the university's research park. We find that university spin-off companies are a greater proportion of the companies in older parks and in parks that are associated with richer university research environments. We also find that university spin-off companies are a larger proportion of companies in parks that are geographically closer to their university and in parks that have a biotechnology focus.
Can a Caged Bird Still Fly? A Comparative Analysis of Judicial Accountability in the People's Reublic of China and New Order Indonesia

Most single-party states establish mechanisms to ensure that judges remain responsible to the government. This paper proposes a new framework for understanding these accountability mechanisms. When the party-state can redesign the constitutional framework, it may institutionalize political control over judges, thus making judges directly accountable to political elites. If a single-party government must govern under a liberal constitutional framework, political elites might instead try to influence judicial outcomes through the illegal distribution of patronage to judges. This paper seeks to explain both models through case studies in the People’s Republic of China and Suharto’s New Order in Indonesia. In assessing both, it suggests that institutionalized accountability in single-party states may in fact be more likely to promote the rule of law than patrimonialism.
Gyrase mutations in laboratory-selected, fluoroquinolone-resistant mutants of Mycobacterium tuberculosis H37Ra.

To characterize mechanisms of resistance to fluoroquinolones by Mycobacterium tuberculosis, mutants of strain H37Ra were selected in vitro with ofloxacin. Their quinolone resistance-determining regions for gyrA and gyrB were amplified and sequenced to identify mutations in gyrase A or B. Three types of mutants were obtained: (i) one mutant (TKp1) had no mutations in gyrA or gyrB; (ii) mutants that had single missense mutations in gyrA, and (iii) mutants that had two missense mutations resulting in either two altered gyrase A residues or an altered residue in both gyrases A and B. The TKp1 mutant had slightly reduced levels of uptake of [14C]norfloxacin, which was associated with two- to fourfold increases in the MICs of ofloxacin, ciprofloxacin, and sparfloxacin. Gyrase mutations caused a much greater increase in the MICs of fluoroquinolones. For mutants with single gyrA mutations, the increases in the MICs were 4- to 16-fold, and for mutants with double gyrase mutations, the MICs were increased 32-fold or more compared with those for the parent. A gyrA mutation in TKp1 secondary mutants was associated with 32- to 128-fold increases in the MICs of ofloxacin and ciprofloxacin compared with the MICs for H37Ra and an eight-fold increase in the MIC of sparfloxacin. Sparfloxacin was the most active fluoroquinolone tested. No sparfloxacin-resistant single-step mutants were selected at concentrations of > 2.5 micrograms/ml, and high-level resistance (i.e., MIC, > and = 5 micrograms/ml) was associated with two gyrase mutations. Mutations in gyrB and possibly altered levels of intracellular accumulation of drug are two additional mechanisms that may be used by M. tuberculosis in the development of fluoroquinolone resistance. Because sparfloxacin is more active in vitro and selection of resistance appears to be less likely to occur, it may have important advantage over ofloxacin or ciprofloxacin for the treatment of tuberculosis.
Efficacy of the Responsive Classroom Approach Results From a 3-Year, Longitudinal Randomized Controlled Trial

This randomized controlled field trial examined the efficacy of the Responsive Classroom (RC) approach on student achievement. Schools (n = 24) were randomized into intervention and control conditions; 2,904 children were studied from end of second to fifth grade. Students at schools assigned to the RC condition did not outperform students at schools assigned to the control condition in math or reading achievement. Use of RC practices mediated the relation between treatment assignment and improved math and reading achievement. Effect sizes (ES) were calculated as standardized coefficients. ES relations between use of RC practices and achievement were .26 for math and .30 for reading. The RC practices and math achievement relation was greater for students with low initial math achievement (ES = .89). Results emphasize fidelity of implementation.
Maximum attainable performance of pulse tube refrigerators

Abstract The nondimensional rate of refrigeration 〈 H 〉 of pulse tubes is shown to have a maximum attainable value of 1/4. The analysis is based on a linearized model in which the regenerator is thermally perfect and has negligible dead volume. The temporal variations are taken to be sinusoidal. At maximum 〈 H 〉 , the coefficient of performance (COP) equals one-half the temperature ratio Tc/Th across the regenerator. In general, COP is a fraction between 0 and 1 of Tc/Th. The difference between the actual power provided at the driver side and the ideal power corresponding to COP=Tc/Th is dissipated in the regenerator. The resulting heat is transported to the warm end of the regenerator, where it is removed as part of the total heat flow rate.
Molecular Dynamics Study of Phosphorylation Mediated Structural Changes in Neurofilament Medium (NF-M) Subunit

Neurofilaments (NFs) are essential building blocks of axonal architecture. Abnormal behavior of these cytostructural elements has been associated with several neuromuscular disorders such as Amyotropic Lateral Sclerosis (ALS). NFs are assembled from three subunits: Low (NFL), Medium (NFM) and Heavy (NFH). These subunits are characterized by a common alpha helical rod domain and carboxyl terminal domains of different lengths specific to each subunit. The tails project from the core of the filament and contain a number of KSP repeat motifs that belongs to the sites for phosphorylation. Especially, the C-terminal tails of NFM and NFH that have relatively longer lengths and higher number of KSP repeats were found to be the key participants of the sidearm-mediated interfilament interactions that regulate the axonal diameter. Though it has been established that that the sidearms play a key functional role, little is known about the roles of individual subunits and the effect of phosphorylation on their behavior. Initially, it was believed that the NFH sidearms play a more integral role in determining axonal structure due to the presence of longer polypeptides and relatively higher KSP repeat units. However, recent studies showed that deleting NFH from neurofilaments does not affect axonal diameter, suggesting that NFM may in fact be the key player. In view of this, it is essential to have an understanding of the morphological behavior of the NFM sidearm in response to physiological conditions. In the present study we carried out MD simulations of human and mouse NFM C terminals under different phosphorylation and ionic conditions. The results from these studies provide useful molecular level insight into the structural changes of NFM sidearms in response to phosphorylation, ionic concentrations. The present study reveals sidearm-mediated regulation mechanism of axonal caliber.
Gliding flight in the American Kestrel (Falco sparverius): An electromyographic study.

Electromyographic (EMG) activity was studied in American Kestrels (Falco sparverius) gliding in a windtunnel tilted to 8 degrees below the horizontal. Muscle activity was observed in Mm. biceps brachii, triceps humeralis, supracoracoideus, and pectoralis, and was absent in M. deltoideus major and M. thoracobrachialis (region of M. pectoralis). These active muscles are believed to function in holding the wing protracted and extended during gliding flight. Quantification of the EMG signals showed a lower level of activity during gliding than during flapping flight, supporting the idea that gliding is a metabolically less expensive form of locomotion than flapping flight. Comparison with the pectoralis musculature of specialized gliding and soaring birds suggests that the deep layer of the pectoralis is indeed used during gliding flight and that the slow tonic fibers found in soaring birds such as vultures represents a specialization for endurant gliding. It is hypothesized that these slow fibers should be present in the wing muscles that these birds use for wing protraction and extension, in addition to the deep layer of the pectoralis. © 1993 Wiley-Liss, Inc.
An architecture and a simulator for parallel signal processing

The real-time implementation of many digital signal processing (DSP) algorithms requires novel algorithm mapping methods and architectures. Some of the architectures developed thus far include data-flow systems, systolic arrays, and wavefront arrays. Ideas from these architectures are combined with the concept of block data flow processing to present the block data flow architecture (BDFA). Key features of the BDFA include direct input/output to all processors, linear data-flow, and globally asynchronous operation. Use of the BDFA for 2-D filtering is presented and analyzed. The analysis is facilitated using timing results generated by a simulator developed with the C programming language. Development of the simulator is discussed in terms of how an architecture like the BDFA can be described and simulated in C. Simulation results show that the increase in throughput with the number of processors is nearly linear. >
Admittance enhancement in force feedback of dynamic systems

A limitation of high-speed contact operations, including robotic assembly, is the magnitude of contact forces resulting from inertial effects. Directly attempting to reduce the apparent inertia of interacting systems through force feedback results in instability. It is shown here that one can introduce a mechanical filter to alter the open-loop system dynamics, making feedback much more effective. Experimental results are presented showing a reduction in apparent inertia by nearly two orders of magnitude.
Effect of ferric tartrate/sodium hydroxide solvent pretreatment on enzyme hydrolysis of cellulose in corn residue.

Lignocellulose containing 62% cellulose was prepared from corn residue by dilute acid hydrolysis using 5% H/sub 2/SO/sub 4/ at 90/sup 0/C. The lignocellulose was then treated with a cellulose solvent consisting of a ferric sodium tartrate complex in 1.5 N sodium hydroxide at levels ranging from 4:1 to 12:1 (solvent volume:corn residue lignocellulose) or a 1.5 N sodium hydroxide solution alone. Subsequent hydrolysis with cellulase enzymes from Trichoderma reesei gave cellulose conversions which were two to three times higher than untreated lignocellulose (30%) and approached 90% conversion after 24 h in the best cases. It was found that increasing cellulase enzyme levels from 3.74 IU/g lignocellulose to 7.71 IU/g lignocellulose increased cellulose conversion by 50% at all pretreatment conditions, while an increase from 7.71 to 10.1 IU/g gave only an additional 5-10% increase. Pretreatment with sodium hydroxide resulted in 5-25% lower conversions than observed for cellulose treated with the solvent, depending on enzyme levels and treatment levels. At high enzyme levels, sodium hydroxide pretreatment is almost as effective enhancing cellulose conversion after 24 h as is pretreatment using the cellulose solvent.
Planning to fail — Reliability needs to be considered a priori in multirobot task allocation

The reliability of individual team members has a substantial and complex influence on the success of multirobot missions. When one robot fails, other robots must be retasked to complete the tasks that were assigned to the failed robot. This in turn increases the likelihood of these other robots failing, since they have more work to do. Existing multirobot task allocation systems consider robot failures only after the fact-by replanning after a failure occurs. We hypothesize that it should be important to consider robot reliabilities when generating an initial plan. In this paper we test this hypothesis in the context of the multirobot exploration problem. We take a simple exhaustive planner and compare the plan it chooses against the optimal plan that takes into account robot failures and the backup plans that occur after failure. Our results show that for this problem domain, making an initial plan without regards to individual robot reliabilities results in choosing a suboptimal plan most of the time, and that the difference in mission performance between the chosen plan and the optimal plan is usually substantial. In brief, in order to successfully plan we must 'plan to fail'.
Exposure to fogger trucks and breast cancer incidence in the Long Island Breast Cancer Study Project: a case–control study

Few studies have supported an association between breast cancer and DDT, usually assessed with biomarkers that cannot discern timing of exposure, or differentiate between the accumulation of chronic low-dose versus acute high-dose exposures in the past. Previous studies suggest that an association may be evident only among women exposed to DDT during biologically susceptible windows, or among those diagnosed with estrogen receptor/progesterone receptor-positive (ER+PR+) breast cancer subtypes. Self-reported acute exposure to a fogger truck, which sprayed DDT prior to 1972, was hypothesized to increase the risk of breast cancer, particularly among women exposed at a young age or diagnosed with ER+PR+ breast cancer. We examined these possibilities in the Long Island Breast Cancer Study Project (LIBCSP) (1,508 cases, 1,556 controls), which included exposure assessment by structured questionnaire and serum samples collected between 1996–1998, using adjusted logistic and polytomous regression to estimate ORs and 95% CIs. Women with ER+PR+ breast cancer had a 44% increased odds of ever seeing a pre-1972 fogger truck compared to other subtypes (OR = 1.44; 95% CI 1.08-1.93). However, there was little variation in the observed increase in breast cancer risk when considering all women who reported seeing a pre-1972 fogger truck at their residence (OR = 1.16; 95% CI 0.98, 1.37), or during hypothesized susceptible windows. Self-reported acute exposure was not correlated with serum concentrations, a biomarker of long-term exposure. These findings support the hypothesis that seeing a fogger truck, a proxy measure for acute DDT exposure, may be associated with ER+PR+ tumors, the most commonly diagnosed breast cancer subtype among American women.
Physicians and Implicit Bias

To the Editors:—The “Perspective” article by Chapman et al.1 helps me see how stereotype and implicit bias influences my clinical caring behavior, and unintentionally enables my contribution to health disparities. Their recommendation for “individuating and perspective taking” helps me structure a model for improvement—I’ve learned from 40 years of practice that the better I know the life story of my patient, the more invested I become and the stronger are my helping attitudes (empathy, congruence, and unconditional positive regard).2 I understand this as an example of “individuating” that enables “perspective taking” (empathy), thus facilitating an enhanced sense of identity (common humanity) with my patient.3 A recently published randomized controlled trial (RCT) of cognitive restructuring resulted in a worthwhile small (effect size ~0.4) 8-week-durable reduction in implicit bias and a larger (~0.6) increased concern about personal prejudice that grew over time.4 Such results can inform evidence-based professional education.
Recent progress in the use of ionic polymers as pseudostationary phases for EKC

This review concerns the introduction, characterization, and application of polymeric pseudostationary phases (PSPs) for EKC since 2004. Achiral and chiral polymers and separations are reviewed, as is the application of polymeric PSPs for the combination of EKC with mass spectrometric detection.
NASA's space communications and navigation test bed aboard the international space station

The NASA SCaN Test Bed flight experiment payload aboard ISS will enable experimenters the unique opportunity to investigate SDRs, navigation, and networking in the space environment. Comprised of three SDRs from industry partners, CoNNeCT allows experimenters to develop and verify new waveforms compliant with the STRS SDR architecture standard, using verified ground systems and then have those waveforms uploaded to the flight SDRs to assess in situ performance and to better understand operational concepts for SDRs in space. In addition to the SDRs, the reprogrammable avionics software allows application software for on-board networking and routing experiments. The flight system communicates with TDRSS at both S-band and Ka-band and can receive within the GPS L-band for navigation waveform development and experiments.
The number of subunits comprising the channel formed by the T domain of diphtheria toxin.

In the presence of a low pH environment, the channel-forming T domain of diphtheria toxin undergoes a conformational change that allows for both its own insertion into planar lipid bilayers and the translocation of the toxin's catalytic domain across them. Given that the T domain contributes only three transmembrane segments, and the channel is permeable to ions as large as glucosamine+ and NAD−, it would appear that the channel must be a multimer. Yet, there is substantial circumstantial evidence that the channel may be formed from a single subunit. To test the hypothesis that the channel formed by the T domain of diphtheria toxin is monomeric, we made mixtures of two T domain constructs whose voltage-gating characteristics differ, and then observed the gating behavior of the mixture's single channels in planar lipid bilayers. One of these constructs contained an NH2-terminal hexahistidine (H6) tag that blocks the channel at negative voltages; the other contained a COOH-terminal H6 tag that blocks the channel at positive voltages. If the channel is constructed from multiple T domain subunits, one expects to see a population of single channels from this mixture that are blocked at both positive and negative voltages. The observed single channels were blocked at either negative or positive voltages, but never both. Therefore, we conclude that the T domain channel is monomeric.
Unconditionally stable, second-order accurate schemes for solid state phase transformations driven by mechano-chemical spinodal decomposition

Abstract We consider solid state phase transformations that are caused by free energy densities with domains of non-convexity in strain-composition space; we refer to the non-convex domains as mechano-chemical spinodals. The non-convexity with respect to composition and strain causes segregation into phases with different crystal structures. We work on an existing model that couples the classical Cahn–Hilliard model with Toupin’s theory of gradient elasticity at finite strains. Both systems are represented by fourth-order, nonlinear, partial differential equations . The goal of this work is to develop unconditionally stable, second-order accurate time-integration schemes, motivated by the need to carry out large scale computations of dynamically evolving microstructures in three dimensions. We also introduce reduced formulations naturally derived from these proposed schemes for faster computations that are still second-order accurate. Although our method is developed and analyzed here for a specific class of mechano-chemical problems, one can readily apply the same method to develop unconditionally stable, second-order accurate schemes for any problems for which free energy density functions are multivariate polynomials of solution components and component gradients. Apart from an analysis and construction of methods, we present a suite of numerical results that demonstrate the schemes in action.
Randomized trials of endovascular therapy for stroke - impact on stroke care.

Five trials that investigated the efficacy of modern endovascular therapies for stroke--MR CLEAN, ESCAPE, SWIFT PRIME, EXTEND IA and REVASCAT--have been published within the past year, changing the landscape of acute stroke management. The trials used a variety of imaging modalities and combinations of treatment approaches, including the mandatory use of intravenous thrombolysis before the initiation of endovascular therapy. All five trials provided strong evidence to support the use of thrombectomy that is initiated within 6 h of stroke onset, prompting worldwide changes in the guidelines for management of acute stroke by endovascular treatment. The benefits of endovascular therapy were observed irrespective of a patient's age, their NIH Stroke Scale score, or whether they received intravenous thrombolysis. In this article, we review the main findings of these recent trials, focusing on key aspects of their designs, and discuss their impact on the future management of patients with acute stroke that results from large-vessel occlusion. We discuss the values of noncontrast CT ASPECTS, perfusion imaging and angiography for selecting patients to receive endovascular interventions. We also consider the role of thrombectomy beyond 6 h after stroke onset, and in patients with posterior circulation strokes.
Genetic variation and dopamine D2 receptor availability: a systematic review and meta-analysis of human in vivo molecular imaging studies

The D2 dopamine receptor mediates neuropsychiatric symptoms and is a target of pharmacotherapy. Inter-individual variation of D2 receptor density is thought to influence disease risk and pharmacological response. Numerous molecular imaging studies have tested whether common genetic variants influence D2 receptor binding potential (BP) in humans, but demonstration of robust effects has been limited by small sample sizes. We performed a systematic search of published human in vivo molecular imaging studies to estimate effect sizes of common genetic variants on striatal D2 receptor BP. We identified 21 studies examining 19 variants in 11 genes. The most commonly studied variant was a single-nucleotide polymorphism in ANKK1 (rs1800497, Glu713Lys, also called ‘Taq1A'). Fixed- and random-effects meta-analyses of this variant (5 studies, 194 subjects total) revealed that striatal BP was significantly and robustly lower among carriers of the minor allele (Lys713) relative to major allele homozygotes. The weighted standardized mean difference was −0.57 under the fixed-effect model (95% confidence interval=(−0.87, −0.27), P=0.0002). The normal relationship between rs1800497 and BP was not apparent among subjects with neuropsychiatric diseases. Significant associations with baseline striatal D2 receptor BP have been reported for four DRD2 variants (rs1079597, rs1076560, rs6277 and rs1799732) and a PER2 repeat polymorphism, but none have yet been tested in more than two independent samples. Our findings resolve apparent discrepancies in the literature and establish that rs1800497 robustly influences striatal D2 receptor availability. This genetic variant is likely to contribute to important individual differences in human striatal function, neuropsychiatric disease risk and pharmacological response.
Oxysterol-related-binding-protein related Protein-2 (ORP2) regulates cortisol biosynthesis and cholesterol homeostasis

Oxysterol binding protein-related protein 2 (ORP2) is a lipid binding protein that has been implicated in various cellular processes, including lipid sensing, cholesterol efflux, and endocytosis. We recently identified ORP2 as a member of a protein complex that regulates glucocorticoid biosynthesis. Herein, we examine the effect of silencing ORP2 on adrenocortical function and show that the ORP2 knockdown cells exhibit reduced amounts of multiple steroid metabolites, including progesterone, 11-deoxycortisol, and cortisol, but have increased concentrations of androgens, and estrogens. Moreover, silencing ORP2 suppresses the expression of most proteins required for cortisol production and reduces the expression of steroidogenic factor 1 (SF1). ORP2 silencing also increases cellular cholesterol, concomitant with decreased amounts of 22-hydroxycholesterol and 7-ketocholesterol, two molecules that have been shown to bind to ORP2. Further, we show that ORP2 binds to liver X receptor (LXR) and is required for nuclear LXR expression. LXR and ORP2 are recruited to the CYP11B1 promoter in response to cAMP signaling. Additionally, ORP2 is required for the expression of other LXR target genes, including ABCA1 and the LDL receptor (LDLR). In summary, we establish a novel role for ORP2 in regulating steroidogenic capacity and cholesterol homeostasis in the adrenal cortex.
Distortion/Interaction Analysis Reveals the Origins of Selectivities in Iridium-Catalyzed C–H Borylation of Substituted Arenes and 5-Membered Heterocycles

The iridium-catalyzed borylation of mono- and disubstituted arenes and heteroarenes has been studied with density functional theory. The distortion/interaction model was employed to understand the origins of selectivities in these reactions. Computations revealed that the transition states for C–H oxidative addition are very late, resembling the aryl iridium hydride intermediate with a fully formed Ir–C bond. Consequently, the regioselectivity is mainly controlled by differences in the interaction energies between the iridium catalyst and arene carbon.
Kidney cancer: Recurrence in renal cell carcinoma: the work is not done.

Recurrences can occur in up to 30% of surgically managed patients with localized renal cell carcinoma. Existing uro-oncological guidelines differ in recommendations of surveillance protocols and identification of patients at risk. A recent study shows that the existence of differing guidelines results in inadequate harms, cancer control and costs.
Influence of Light on Diapause in the Boll Weevil I. Dependence of Diapause Response on the Spectral Composition of the Light Used to Extend the Photoperiod

Regions of the near-ultraviolet and visible spectrum effective for inducing diapause suppression in the boll weevil, Anthonomus grandis Boheman, were investigated. One group of weevils was exposed to 11 hours of fluorescent light-time and 13 hours of dark-time that initiated diapause (L11:D13); the 2nd group was exposed to 13 hours of fluorescent light-time and 11 hours of dark-time that inhibited diapause (L13:D11). A 3rd group was exposed to 11 hours of fluorescent light-time followed by 2 hours of illumination with narrow wavebands of light of different spectral compositions and 11 hours of dark-time (L11+2:D11). The spectral region most effective for suppressing diapause was found to be between 400-665 nm. The 359-390 nm and 670-1000 nm spectral regions were less effective.
Mica paper tape for high voltage motor and generator stator windings

Improved functional properties and process simplification now can be attained through the use of solventless, resin-filled Mica Mat tapes used for high voltage ground insulation. Previously, all B-staged resin-filled tapes composed of either flake mica or mica paper have been manufactured with resin/solvent solutions because the solvents were necessary to reduce the viscosity of the resin for impregnation and to soften the tapes for application. However, when solvents are used, removal of them is difficult, costly, and complete removal is often virtually impossible.
Pediatric Germ Cell Tumors: Protocol Update for Pathologists:

The therapy for pediatric germ cell tumors has historically been widely variable and institution dependent. The efforts to provide consistent, biology-driven therapy through Intergroup protocols has been a relatively recent phenomenon that has provided the framework for future protocol designs. The first Intergroup protocols confirmed that stage I malignant testicular germ cell tumors and immature teratomas at all sites in children could be treated with surgery alone followed by close observation. Future protocols currently in the planning stages may extend this low-risk category to stage I ovarian germ cell tumors of all histologic types. Low-stage extragonadal germ cell tumors may be placed in a new intermediate risk category. Particular pathologic issues that were raised and reported during the first protocols and that may impact on future protocol design include the presence and size of foci of endodermal sinus tumors within low-stage immature teratomas at all sites. Accurate staging will grow more critical in future protocols. The ability to recruit international cooperative groups will determine the success of chemotherapy tailored to specific subgroups that now must be lumped for statistical purposes. Lastly, companion biologic studies will be critical to defining the different subtypes of germ cell tumors and to determining predictors of biologic behavior.
A Molecular Cytogenetic View of Chromosomal Heterogeneity in Solid Tumors

The concept that cancers progress, in large part, through accumulation of multiple genetic abnormalities is generally accepted.1,2,3 The order of progression is best established for colorectal cancer.3 The development of genetic instability is thought to be a key aspect of tumor progression4,5 enabling accumulation of the multiple abnormalities required for a complete metastatic phenotype. Several genetic abnormalities that lead to instability have been identified. These involve genes that code for proteins involved in detection and repair of genetic damage,5 maintenance of telomere length6 and apoptosis.7,8 However, the magnitude and type of damage that is accumulated as a result of these defects is only now beginning to be appreciated. The application of molecular cytogenetic techniques such as fluorescence in situ hybridization (FISH9,10) and comparative genomic hybridization (CGH11) are particularly powerful for the study of damage that results in changes in the structure or number of copies of genomic DNA. FISH allows visualization of specific segments of DNA in single cells and therefore provides information about the variation among cells in the number of copies and the organization of these target sequences. CGH, on the other hand provides a genome-wide overview of changes in relative DNA sequence copy number that occur in the majority of cells of a tumor. Importantly, CGH maps changes onto a normal representation of the genome so that they are easily interpreted. These techniques are particularly useful for studies of DNA sequence copy number changes in spontaneous solid tumors since they do not require cell culture and can be applied to archived tumor material.
Human Fibroblasts for Large-Scale “Omics” Investigations of ATM Gene Function

ATM (gene mutated in ataxia-telangiectasia) is a critical central component of the pleiotropic responses of cells to ionizing radiation-induced stress. To gain insight into molecular mechanisms and to enhance our understanding of ATM functions, we have advanced a human model cell system, derived from genetically defined immortal fibroblasts, and we have applied high-throughput genomic, proteomic and metabolomic technologies for a systems level analysis. The cellular characterizations reported here provide the background for application of a systems analysis to integrate transcription, post-translational modifications and metabolic activity induced by exposure of cells to ionizing radiation. We present here a summary of the derivation and characterization of cells comprising this model cell system and review applications of this model to systems analysis of ATM functions.
Note: An improved solenoid driver valve for miniature shock tubes

A solenoid driver valve has been built to improve the operating performance of diaphragmless shock tubes, which are used for high pressure, high temperature chemical kinetics, and fluid mechanics studies. For shock tube driver application, the most important characteristics are those of sealing, strength, and quality of the generated shock waves and repeatability of opening characteristics and therefore subsequent post-shock conditions. The main features of the new driver valve are a face o-ring sealing design of the valve, the large internal volume, and through inserts near the solenoid core: adjustable opening characteristics of the valve.
A Review of Hailstone-Hailstorm Numerical Simulations

Various studies of hailstone growth and hailstorm development are classified into four categories utilizing the concepts of coupled and uncoupled microphysics-dynamics and steady-state or time-dependent airflows. These papers are reviewed as to their principal results and then summarized with respect to their conclusion about the primary hailstone growth regions in a cloud, the important growth modes, the effect of stone recycling and tilted updrafts, the occurrence of very large liquid water contents, the type of hail embryo, etc. Various problems of numerical, dynamical, and microphysical origin are discussed. Prospects for successful and useful numerical simulation of hailstorms and hailstone growth are considered to be good.
Some recent advances in wideband phased arrays

Wideband phased arrays are needed to handle wideband signals and for multifunction radars. Multifunction phased array technology reduces the number of antennas needed aboard Navy ships and contributes to lower antenna radar cross section.
Dielectric Properties and Applications of Strontium Titanate Thin Films for Tunable Electronics

The dielectric constant (e) of ferroelectric materials, such as (Ba,Sr)TiO3 (BST) and SrTiO3 (STO), depends strongly on the applied electric field [1, 2]. This phenomenon has been referred to as the dielectric nonlinearity. The dielectric nonlinearity of ferroelectrics has been recognized to be significant for various microwave device applications, because the frequency and phase characteristics of the devices depend on the dielectric constants of both the substrate and the ferroelectric materials in them, and tuning of these characteristics is possible by applying an electric bias to the ferroelectrics [3]. Such tuning is extremely desirable, for example, in high temperature superconductor (HTS) microwave filters, where post-fabrication tuning of bandpass/bandreject frequencies is required. The frequency tuning allows such applications as fast switching of the bandpass and bandreject frequencies to block or transmit different frequencies adoptively, and to change the desired frequency range quickly. Another example is microwave phase shifter, in which the tuning of the dielectric constant changes the lumped circuit capacitance, which in turn affects the amount of the phase shift. An important application of such phase shifters is phased-array antennas which can be electronically steered.