cssi/SciSciGPT-SciSciNet huggingface dataset:
Reconstruction of the superior vena cava: Benefits of postoperative surveillance and secondary endovascular interventions

Abstract Purpose: Superior vena cava (SVC) reconstructions are rarely performed; therefore the need for surveillance and the results of secondary interventions are unknown. Methods: During a 14-year period 19 patients (11 male, 8 female; mean age 41.9 years, range 8 to 69 years) underwent SVC reconstruction for symptomatic nonmalignant disease. Causes included mediastinal fibrosis (n = 12), indwelling foreign bodies (n = 4), idiopathic thrombosis (n = 2), and antithrombin III deficiency (n = 1). Spiral saphenous vein graft (n = 14), polytetrafluoroethylene (n = 4), or human allograft (n = 1) was implanted. Results: No early death or pulmonary embolism occurred. Four early graft stenoses or thromboses (spiral saphenous vein graft, n=2, polytetrafluoroethylene, n=2) required thrombectomy, with success in three. During a mean follow-up of 49.5 months (range, 4.7 to 137 months), 95 imaging studies were performed (average, five per patient; range, one to 10 studies). Venography detected mild or moderate graft stenosis in seven patients; two progressed to severe stenosis. Two additional grafts developed early into severe stenosis. Four of 19 grafts occluded during follow-up (two polytetrafluoroethylene, two spiral saphenous vein graft). Computed tomography failed to identify stenosis in two grafts, magnetic resonance imaging failed to confirm one stenosis and one graft occlusion, and duplex scanning was inconclusive on graft patency in 10 patients. Angioplasty was performed in all four patients with severe stenosis, with simultaneous placement of Wallstents in two. One of the Wallstents occluded at 9 months. Repeat percutaneous transluminal angioplasty was necessary in two patients, with placement of Palmaz stents in one. Only one graft occlusion and one severe graft stenosis occurred beyond 1 year. The primary, primary-assisted, and secondary patency rates were 61%, 78%, and 83% at 1 year and 53%, 70%, and 74% at 5 years, respectively. Conclusions: Long-term secondary patency rates justify SVC grafting for benign disease. Postoperative surveillance with contrast venography is indicated in the first year to detect graft problems. Endovascular techniques may salvage and improve the patency of SVC grafts. (J Vasc Surg 1998;27:287-301.)
The new nucleoporin: regulator of transcriptional repression and beyond.

Transcriptional regulation is a complex process that requires the integrated action of many multi-protein complexes. The way in which a living cell coordinates the action of these complexes in time and space is still poorly understood. Recent work has shown that nuclear pores, well known for their role in 3′ processing and export of transcripts, also participate in the control of transcriptional initiation. We have recently begun to explore how nuclear pores interface with the well-described machinery that regulates initiation. This work led to the discovery that specific nucleoporins are required for binding of the repressor protein Mig1 to its site in target promoters. Nuclear pores are therefore involved in repressing, as well as activating, transcription. Here we discuss in detail the main models explaining our result and consider what each implies about the roles that nuclear pores play in the regulation of gene expression.
Role of Tc-99m IDA scintigraphy in the evaluation of hepatobiliary trauma.

Each year approximately 52 million Americans are injured, of which 11 million require hospitalization and 110.000 die. This has an associated health care cost of 3 billion dollars. 1–3 Hepatobiliary injuries have always constituted a significant area of involvement. They have become more easily detectable since the advent of technetium-99m analogs of iminodiacetic acid (IDA). Biliary leakage secondary to other causes, such as inflammation, neoplasm, and iatrogenic factors are also well demonstrated in a safe, simple, and rapid manner with radionuclide imaging. The relatively low patient radiation dose that is associated with these procedures permits follow-up studies when necessary.
Australian Winter Mountain Storm Clouds: Precipitation Augmentation Potential

Abstract Two Australian winter mountain storm field research projects were conducted by the Commonwealth Scientific and Industrial Research Organisation Division of Atmospheric Research and the Desert Research Institute Atmospheric Sciences Center in the austral winters of 1988 and 1990. These projects gained information about winter storms in support of the ongoing Melbourne Water randomized cloud seeding experiment aimed at increasing runoff into Melbourne's main water supply, the Thomson Reservoir. This paper discusses some of the 1988 instrumentation data. One variable of interest is the precipitation augmentation potential π. It is the difference between (a) the horizontal supercooled liquid water flux in the clouds crossing the mountains and (b) the vertical precipitation flux at the surface from the clouds. These fluxes are based on calculations of supercooled liquid water depth in clouds with a microwave radiometer, Omegasonde wind velocity, and rates of precipitation from gauges. It was found tha...
Pyrazole NNRTIs 3: Optimisation of physicochemical properties

Our efforts to reduce overall lipophilicity and increase ligand-lipophilicity efficiency (LLE) by modification of the 3- and 5-substituents of pyrazole 1, a novel non-nucleoside HIV reverse transcriptase inhibitor (NNRTI) prototype were unsuccessful. In contrast replacement of the substituted benzyl group with corresponding phenylthio or phenoxy groups resulted in marked improvements in potency, ligand efficiency (LE) and LLE.
Computerized classification of benign and malignant masses on digitized mammograms: A study of robustness

Rationale and Objectives. The purpose of this study was to evaluate the robustness of a computerized method developed for the classification of benign and malignant masses with respect to variations in both case mix and film digitization. Materials and Methods. The classification method included automated segmentation of mass regions, automated feature-extraction, and automated lesion characterization. The method was evaluated independently with a 110-case database consisting of 50 malignant and 60 benign cases. Mammograms were digitized twice with two different digitizers (Konica and Lumisys). Performance of the method in differentiating benign from malignant masses was evaluated with receiver operating characteristic (ROC) analysis. Effects of variations in both case mix and film digitization on performance of the method also were assessed. Results. Categorization of lesions as malignant or benign with an artificial neural network (or a hybrid) classifier achieved an area under the ROC curve, A z , value of 0.90 (0.94 for the hybrid) on the previous training database in a round-robin evaluation and A z values of 0.82 (0.81) and 0.81 (0.82) on the independent database for the Konica and Lumisys formats, respectively. These differences, however, were not statistically significant ( P > .10). Conclusion. The computerized method for the classification of lesions on mammograms was robust with respect to variations in case mix and film digitization.
Historical and sociopolitical context of the western watersheds movement

: The 1990s have featured a rapid proliferation of “watershed initiatives” in the western United States and elsewhere. Watershed initiatives are ad hoc, voluntary associations typically featuring both governmental and non-governmental actors organized together to collaboratively seek new strategies for addressing water and related natural resource problems at physically relevant regional scales. These efforts are a response to historical and sociopolitical trends that have resulted in increasingly ineffective forums and processes of resource management decision-making, and that have subordinated the role of local stakeholders in problem-solving efforts. In most cases, watershed initiatives appear to provide a pragmatic vehicle for resource managers and stakeholders to address common concerns in a more efficient manner than is otherwise possible, and as such, deserve further application and continued support.
Spin Coulomb Drag in a One-Dimensional Spin-Polarized Conductor

The spin Coulomb drag is a distinctive feature of spin-polarized transport. The current of majority spins can induce a current of minority spin carriers via the transconductivity. The friction is caused by the Coulomb interaction between up- and down-spin. This interaction reduces the current but does not change the spin-polarization. We calculate the conductivities and the transconductivity for a spin-polarized interacting 1-D electron gas for a lattice without inversion symmetry in the presence of nonmagnetic impurities. Due to the Luttinger liquid properties, the temperature dependence of the transport correlation functions follows power laws of with nonuniversal exponents.
Abstract B73: Lapatinib‐mediated radiosensitization of EGFR+/basal breast cancer correlates withERK inhibition in vivo and requires MEK/ERK inhibition in vitro

To determine whether the dual EGFR/HER2 kinase inhibitor lapatinib can radiosensitize EGFR+ breast cancer in vivo, mice bearing xenografts of basal‐like/EGFR+ SUM149 breast cancer cells were treated with lapatinib and fractionated radiation therapy over a 10 d period and tumor growth inhibition determined and correlated with changes in activation of downstream signaling to ERK1/2 and AKT by immunohistochemistry. Basal‐like/EGFR+ SUM149 breast cancer tumors were completely resistant to treatment with lapatinib alone but highly growth impaired with lapatinib + radiation exhibiting an enhancement ratio average of 2.75 and a fractional tumor product ratio average of 2.06 over the duration of the study. Immunohistochemical analysis demonstrated that radiosensitization by lapatinib correlated with inhibition of ERK1/2 but not AKT. In vitro analysis of other basal breast cancers consistently demonstrated a loss of radiation induced MEK1/2 inhibition with lapatinib treatment. Treatment of the SUM102 basal‐like/EGFR+ cell line with the MEK inhibitor CI1040 resulted in radiosensitization at levels similar to that seen with lapatinib alone. Furthermore, constitutive activation of RAF in SUM102 cells abolished the ability of lapatinib to radiosensitize these cells and resulted in enhanced radioresistance relative to parental cells. Collectively, this work demonstrates that lapatinib radiosensitizes EGFR+/basal‐like breast cancer both in vitro and in vivo in a MEK/ERK dependent manner, and suggests that lapatinib in combination with fractionated radiation therapy may provide an effective treatment option for breast cancers of this subtype. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B73.
Optical electron transfer processes. The dependence of intervalence line shape and transition energy on chromophore concentration

Abstract Optical electron transfer in the mixed-valence cation of biferrocenylacetylene (BF + ) has been examined in CD 2 Cl 2 solvent. The intervalence absorption line shape is relatively narrow at both low and high chromophore concentrations, but broader at intermediate concentrations. The transition energy for metal-to-metal charge transfer increases from ≈4440 cm −1 at infinite dilution to 5995 cm −1 for 3.8 mM BF + . Related effects exist due to added electrolyte. Neither the electrolyte nor chromophore concentration effects are expected from a simple reading of electron transfer theories. Nevertheless, both phenomena can be understood and within the context of theory upon careful consideration of the effects of ion-pairing (and tripling) equilibria upon electron-transfer energetics.
The influence of spatial scale on cross‐taxon congruence patterns and prediction accuracy of species richness

Summary A comparison of species richness patterns of butterflies and birds was made using data from two grids of squares (small squares 137.5 km on a side and large squares 275 km on a side) covering western North America. Using geostatistical procedures, we found that the spatial patterns of species richness of these two taxa were related. The influence of grain size on the strength of this relationship was investigated by analysing the two data sets. For both data sets, the number of butterfly species in a square was a statistically significant predictor of the corresponding number of bird species. However, cross-validation techniques showed that the marginal improvement in prediction accuracy due to including butterflies as a predictor was greater in the large-square data. We explored the effect of areal extent on cross-taxon congruencies by investigating species richness patterns in four subsets of the small-square data. In regions with smaller areal extent, the cross-taxon congruence patterns were not substantially different from the pattern found in the full data set. Finally, using data-splitting techniques, we explored the relationships between prediction accuracy of species richness, sample size, areal extent of the sample, and grain size.
Assignments of the nπ∗ singlet states of p-benzoquinone

Abstract The vapor phase fluorescence spectra of p -benzoquinone- h 4 and d 4 are reported and discussed in relation to the assignment of the low lying singlet states. The low temperature, polarized single crystal electronic absorption spectra of p -benzoquinone and several of its isotopic derivatives are reported. From the isotope shifts and band polarizations of the various vibronic origins, a detailed vibronic analysis is offered of the electronic absorption spectrum of p -benzoquinone which indicates a near degeneracy of the 1 A u and 1 B 1 g electronic states.
Sexual abuse: Helping the church recognize and respond to victims

Sexual abuse victims can be members of churches which serve people in many ways, yet some of these victims are unable to report the abuse to a church leader or other members. In the church's efforts to understand and meet needs in the world today, helping victims of sexual trauma is part of God's work to touch lives through ministry in His church. Whether these victims are children or adults, the church can play an active role in recognizing and meeting needs of sexually abused persons.
Ablation Measurements and Analysis of Solid Carbon Dioxide Models at Mach 3

Three-dimensional ablation measurements, acquired using solid carbon dioxide for the model material and carried out at Mach 3, are compared to predictions of a computational model that incorporates fluid dynamics and solid-body response. Models were formed in situ by mounting three-dimensional printed molds on a hollow sting, through which liquid carbon dioxide flowed. The blowdown wind tunnel, operating with a vacuum tank connected to its outlet, provided stagnation pressures through a wide range (6.0 to 45 psia) while maintaining a nearly constant stagnation temperature for all tests (∼295 K). Three synchronized high-speed cameras captured the model recession from different angles while multiple low-power lasers projected structured arrays of dots onto the otherwise visually uniform model. Commercially available software was applied to quantify the recession data. As expected, recession rates were largest at the nose of each model and increased with stagnation pressure. A quantitative comparison of the...
Behavioral treatment of chronic pain: variables affecting treatment efficacy

Abstract Behavioral approaches to pain management have been shown to be efficacious in many instances but many of the variables indicating or contra-indicating such treatment remain unspecified. The data reported here demonstrated that while patients referred by both Disability and Medical Subspecialties showed improvement in pain report, affect, and feelings of control, those patients referred by Disability improved reliably less, remain hospitalized longer and were reliably less compliant. These data can be understood within an operant conditioning conceptualization of illness behavior.
Rapid, specific method for diethylstilbestrol analysis using an in-line photochemicals reactor with high-performance liquid chromatography and fluorescence detection

Low ppb* levels of diethylstilbestrol in biological samples of human and animal origin can be determined using a unique in-line separation–photoreaction–fluorescence detection analytical system. After a very simple extraction procedure, the diethylstilbestrol is separated from interfering substances by high-performance liquid chromatography, photoconverted to a fluorescent product, and detected by fluorescence spectroscopy at optimised excitation–emission wavelengths. A sample can be extracted and anlysed in less than 1 h.
Hematopoietic stem cells give rise to perivascular endothelial-like cells during brain tumor angiogenesis.

Bone marrow (BM) cells have recently been shown to give rise to skeletal, hepatic, cardiac, neural, and vascular endothelial tissues. However, it has been shown that this is the result of cell fusion rather than transdifferentiation of hematopoietic stem cells (HSC). For this study, we established a mouse model of brain tumor growth to investigate the differentiation potential of HSC into endothelial cells during brain tumor-induced angiogenesis. Nontransgenic (GFPneg) recipient mice were lethally irradiated, and their hematopoietic cells were subsequently repopulated by transplantation of a single green fluorescent protein (GFP)-expressing HSC. Rat glioma (RT-2/RAG) cells were then injected into the striatum of the chimeric mice 6–8 weeks post-transplantation. The animals were sacrificed 3–9 days after tumor implantation, and the mobilization, temporal-spatial distribution, and lineage-specific marker expression profile of the GFP+ cells within the growing tumor were analyzed. We saw that GFP+ cells gave...
Artificial Urinary Sphincter Migration Causing Obstructive Renal Failure in a Solitary Kidney

The artificial urinary sphincter (AUS) is a successful mode of therapy for women with stress urinary incontinence from intrinsic sphincter deficiency.1 Despite its efficacy, AUS placement is frequently associated with complications such as mechanical failure, urethral erosion and infection. We report a rare complication of sphincter cuff migration causing intramural ureteral obstruction and subsequent acute renal failure in a patient with a solitary kidney. CASE REPORT
Cochlear mechanisms of frequency and intensity coding. I. The place code for pitch

In the past, several researchers have reported a substantial shift in the peak of the tone-evoked excitation pattern toward the base of the cochlea following an increase in the SPL of the stimulating tone. Evidence for such peak shifts has been found in the responses of auditory nerve fibers, cochlear microphonics, and the responses of outer hair cells and supporting cells in the cochlea, as well as in basilar membrane vibration measurements, and indirectly, in psychophysical data. However, direct evidence for such a peak shift in inner hair cell (IHC) responses has been relatively sparse. If the peak shift is preserved in the information conveyed to the auditory nerve fibers by the IHCs, the classical 'place theory' for frequency coding in the cochlea requires modification. In this study, the nature and extent of the SPL-dependent peak shift is examined with the help of recordings in the IHCs and other cells of the organ of Corti in the 0.5-2.5 kHz region of the Mongolian gerbil cochlea. It is demonstrated that the peak shift is a universal phenomenon in the diverse cell types in this region of the cochlea. Most importantly, a large SPL-dependent peak shift is demonstrated in IHC responses. On the other hand, the recordings indicate that the apical cutoff of the spatial excitation pattern is SPL-independent. We conclude, therefore, that the place theory of pitch perception must be abandoned or at least modified.
Isotope-shift measurement of the NO2- gap mode spectrum in KI with persistent ir spectral holes.

Persistent infrared spectral holes are used to identify the isotope shifts of the far-infrared gap modes associated with N${\mathrm{O}}_{2}^{\ensuremath{-}}$ in KI. Two of the modes are determined to be translational while the third has a mixed translational-librational character. The properties of the mixed mode disagree in a fundamental way with the predictions of the previous lattice-dynamical calculation for this defect-lattice system.
Mean-lower partial moment asset pricing and the regulation of property—liability insurance rates

Abstract The mean-lower partial moment (E-L) asset pricing model is investigated as a theoretically preferable alternative to the mean—variance (E-V) model currently used for the regulation of property—liability insurance rates. An E-L regulatory model, specific to the property—liability underwriting return function, is derived. Empirical tests show that the E-L model is reliable relative to the E-V model. The E-L model tends to generate lower ‘fair’ profit rates on underwriting than does the E-V model.
Envelope and order domain analyses of a nonlinear torsional system decelerating under multiple order frictional torque

Abstract The broader goal of this article is to re-examine the classical machinery shut down vibration problem in the context of a two degree of freedom nonlinear torsional system that essentially describes a braking system example. In particular, resonant amplifications during deceleration, as excited by a multi-order rotor surface distortion and pad friction regime, are investigated using a nonlinear model, and the order domain predictions are successfully compared with an experiment. Then a quasi-linear model at higher speeds is proposed and analytically solved to obtain closed form expressions for speed-dependent torque as well as its envelope curve. The Hilbert transform is also utilized to successfully calculate the envelope curves of both quasi-linear and nonlinear systems. Finally, the multi-term harmonic balance method is applied to construct semi-analytical solutions of the nonlinear torsional model, and the order domain results are successfully compared with measurements. New analytical solutions provide more insight to the speed-dependent characteristics given instantaneous frequency excitation.
Primary and beta-secondary deuterium isotope effects in N-deethylation reactions.

Lidocaine (1), labeled specifically with deuterium in the ..cap alpha..-methylene (lidocaine-d/sub 4/, 2) and ..beta..-methyl (lidocaine-d/sub 6/, 3) carbon atoms of the terminal amino group, was used to probe the mechanism of oxidative N-deethylation by rat liver microsomes. The reaction rates were determined by measuring the formation of acetaldehyde colorimetrically. This general assay for oxidative N-deethylation reactions has the advantages of being rapid, producing a relatively stable colored derivative and being linear over the range of 0.25-4 ..mu..g of acetaldehyde formed per milliliter of incubate. Deuterium substitution at the methylene carbon atoms, the presumed site of initial oxygen insertion, revealed a k/sub H//k/sub D/ = 1.49 +- 0.11 and a K/sub m//sup D//K/sub m//sup H/ = 1.23. Deuterium substitution on the terminal methyl groups showed a k/sub H//k/sub D/ = 1.52 +- 0.10 and a K/sub m//sup D//K/sub m//sup H/ = 0.92. The results are explained in terms of both primary and secondary isotope effects on a possible rate-determining step in the N-deethylation sequence.
In Vitro Study of the Effects of Volume Changes on Parameters of the Radiofrequency Amplitude Versus Time Curve With Sonicated Albumin

The ultrasound time intensity curve parameters obtained from an intracoronary injection of either sonicated albumin or Albunex are used to quantify coronary flow changes. How much the volume changes that accompany the flow changes affect various time intensity curve parameters is unknown. Accordingly, we designed a variable-volume in vitro chamber connected to a flow pump operating at four predetermined flow settings (44 to 184 ml/minute). Injections of either sonicated albumin or Albunex were given proximal to a mixing chamber, which then passed through the scanning chamber at three different volume settings. The parameters studied were area under the curve, corrected peak contrast intensity, ascending and descending slopes of the curve, time to peak radiofrequency signal, the time required to reach half peak intensity (half time up), the time required to decay to half peak intensity (half time down), and total transit time (the time from appearance to disappearance of 10% of peak intensity). Although area, half time up, half time down, and transit time all correlated with flow when volume was held constant, only transit time (and the natural logarithm of the transit time) correlated strongly with flow changes when simultaneous changes in volume occurred. Transit time also correlated with volume changes when flow was held constant, but was more sensitive to flow changes. These data may explain why transit time variables may still be able to detect flow changes in the coronary circulation despite a simultaneous change in myocardial blood volume.
Arsenic and phosphorus in seagrass leaves from the Gulf of Mexico

Abstract Arsenic is a common contaminant in the marine environment, but little is known about arsenic in seagrasses. Arsenate is taken up by the phosphate uptake systems of plants, and there is often a relationship between P availability and As uptake. We sampled green leaves of the seagrass Thalassia testudinum from six estuaries in the Gulf of Mexico to document the As content of seagrasses and to determine the relationships between P availability and As. Arsenic content of seagrasses was generally lower than literature values of other marine primary producers. Arsenic content varied from 0.90 to 3.36 ppm and phosphorus content varied from 544 to 6294 ppm, and there were significant differences among the estuaries studied. Nutrient stoichiometry (N:P) indicated that there were differences in P availability among estuaries: Charlotte Harbor had high P availability, while St. Joseph Bay and Florida Bay were P-limited. The Homosassa River, the Anclotte Estuary and Tampa Bay had intermediate P availability. When data from all estuaries were pooled, there was a significant, negative relationship between P and As content, as predicted by the model of competitive uptake of As and P. However, more extensive sampling within one estuary (Florida Bay) showed a significant positive relationship between P and As, suggesting that factors other than strict competitive uptake kinetics influence the relative content of As and P. We suggest that the P and As availability ratio in estuaries, and therefore in the seagrasses that inhabit them, is largely controlled by the relative importance of freshwater and marine inputs of the two elements.
Vapor-Phase Stoichiometry and Heat Treatment of CdTe Starting Material for Physical Vapor Transport

Six batches of CdTe, having total amounts of material from 99 to 203 g and gross mole fraction of Te, X(sub Te), 0.499954-0.500138, were synthesized from pure Cd and Te elements. The vapor-phase stoichiometry of the assynthesized CdTe batches was determined from the partial pressure of Te2, P(sub Te2) using an optical absorption technique. The measured vapor compositions at 870 C were Te-rich for all of the batches with partial pressure ratios of Cd to Te2, P(sub Cd)/P(sub Te2), ranging from 0.00742 to 1.92. After the heat treatment of baking under dynamic vacuum at 870 C for 8 min, the vapor-phase compositions moved toward that of the congruent sublimation, i.e. P(sub Cd)/P(sub Te2) = 2.0, with the measured P(sub Cd)/P(sub Te2) varying from 1.84 to 3.47. The partial pressure measurements on one of the heat-treated samples also showed that the sample remained close to the congruent sublimation condition over the temperature range 800-880 C.
Criteria analysis and validation of the reliability of Web services-oriented systems

As Web services become more prevalent, the need to ensure their quality increases. This paper explores the criteria of reliability of Web services-oriented systems, and discusses how to design and generate test cases to conduct tests over Web services. A prototype system is constructed to test the effectiveness and efficiency of our algorithms. The preliminary results show that our approach facilitates the testing of services-oriented systems.
SU-E-T-609: Improving the Efficiency of VMAT Plan Optimization by Using Sparse Decomposition Method.

Purpose: Volumetric modulated arc therapy (VMAT) is capable of delivering highly conformable dose distribution efficiently. Its planning is, however, more computationally intensive and requires a huge amount of memory space for optimization. We present an efficient sparse decomposition method for VMAT plan optimization.Methods: A quadratic objective function with volumetric constraints is expressed as a function of the aperture shapes and weights of the incident beams. The algorithm generates a sequence of iterates to solve the optimization problem. Each step of iteratively reweighed method is to be updated by solving the subproblem involving a quadratic (L2) term and a sparsity‐inducing regulation (L1) term. Through the sparse decomposition techniques of the given problem, the deliverable apertures are directly generated. The shape of each aperture is iteratively rectified to be a sequencing of arc using the manufacture constraints. An initial arc spacing of 8 degree creates 45 beams directions for a single arc, 360 degree. The angular separation is equispaced every 2 degree over the end of optimization cycle. The optimization is implemented for a Varian TrueBeamTM STX linac beams with and without flattening filters available. Three clinical cases, head and neck, lung, and prostate, have been studied for the purpose of evaluating the planning efficiency and quality of the plans. Results: The target dose coverage and critical structure sparing of VMAT plan are comparable to those of IMRT plans. The VMAT plan delivers lower doses to other OARs while keeping the similar target dose coverage to IMRT plan. The VMAT plan optimizations takes less than 3 minutes on average of the cases indicating great efficiency compared to existing methods. Conclusions: The results demonstrate that the proposed method provides competent computational efficiency for optimizing VMAT plan. The method substantially improves the speed and accuracy of VMAT plan optimization and makes future on‐treatment adaptive re‐planning possible.
A label-free optical biosensor with microfluidics identifies an intracellular signalling wave mediated through the β2-adrenergic receptor

The canonical model of G protein-coupled receptor (GPCR) signalling states that it is solely initiated at the cell surface. In recent years, a handful of evidence has started emerging from high-resolution molecular assays that the internalized receptors can mediate the third wave of signalling, besides G protein- and β-arrestin-mediated signalling both initiating at the cell surface. However, little is known about the functional consequences of distinct waves of GPCR signalling, in particular, at the whole cell system level. We here report the development of label-free biosensor antagonist reverse assays and their use to differentiate the signalling waves of an endogenous β2-adrenergic receptor (β2-AR) in A431 cells. Results showed that the persistent agonist treatment activated the β2-ARs, leading to a long-term sustained dynamic mass redistribution (DMR) signal, a whole cell phenotypic response. Under the persistent treatment scheme in microplates, a panel of known β-blockers all dose-dependently and completely reversed the DMR signal of epinephrine at a relatively low dose (10 nM), except for sotalol which partially reversed the DMR. Under the perfusion conditions with microfluidics, the subsequent perfusion with sotalol only reversed the DMR induced by epinephrine or isoproterenol at 10 nM, but not at 10 μM. Furthermore, the degree of the DMR reversion by sotalol was found to be in an opposite relation with the duration of the initial agonist treatment. Together, these results suggest that the hydrophilic antagonist sotalol is constrained outside the cells throughout the assays, and the early signalling wave initiated at the cell surface dominates the DMR induced by epinephrine or isoproterenol at relatively low doses, while a secondary and late signalling wave is initiated once the receptors are internalized and contributes partially to the long-term sustainability of the DMR of epinephrine or isoproterenol at high doses.
Behavior of bulk micromachined silicon flow sensor in the negative differential resistance regime

The performance of a bulk micromachined silicon flow sensor in the negative differential resistance (NDR) regime is investigated for air flow measurements. The NDR regime of operation is obtained by boosting the pulse height in typical pulse mode operation. Our measurements show that operation in the NDR regime results in increased sensitivity compared to operation in the saturation regime. The increased sensitivity in this regime occurs at relatively higher temperatures with a possible increase in power consumption. In the pulse mode of operation, with a 3 mA, 100 ms pulse, the unamplified linear sensitivity is 40 mVs m-1 for the flow velocities in the range of 5.3-21.0 m s-1. In the NDR regime with a 6 mA, 100 ms pulse, the latter is 67 mVs m-1 for the same flow velocity range. In addition, driving the sensor into the NDR regime results in a response curve (impulse shaped) which shows the potential use of different parts of the pulse response to ascertain flow information. Furthermore, for the first time, we report here the pulse type output voltage made possible in the NDR regime for a continuous current input to the sensor.
Hexavalent chromium review, part 2: Chemistry, occurrence, and treatment

This is the second article in a two-part review of the current state of the science regarding hexavalent chromium. Part 1 discussed chromium health effects, regulations, and analysis. This review begins by discussing the chemistry of the two predominant chromium oxidation species: trivalent chromium and hexavalent chromium (Cr(VI)), including soluble and particulate forms. Although Cr(VI) is the species of concern for human health effects, both forms must be considered because they can be interconverted by a variety of oxidants and reductants. Although it is generally assumed that Cr(VI) comes from anthropogenic contamination, this review highlights many reports of it naturally occurring. This article also summarizes the limited data available on chromium occurrence in drinking water sources and finished water. Finally, a range of treatment methods and limitations associated with each is listed. Utilities should also consider potential sources and sinks of chromium within the treatment plant and distribution system.
Vasopressin-induced coronary constriction at low perfusion pressures

We studied the effects of intracoronary vasopressin on the relationship between pressure and flow in the coronary circulation of anaesthetised swine. In addition to measurements at control levels, diastolic pressure-flow relationships were constructed from steady-state points below a coronary pressure of 50 mmHg, where endogenous vasodilatation is strongly stimulated. At baseline pressures, flow fell 28% with maximal vasopressin effect. At all levels of diastolic pressure below 50 mmHg vasopressin also decreased flow, eg, at 30 mmHg flow was depressed by 40%. The slope of the steady-state pressure-flow relationship fell from 1.21 to 0.75 ml·min−1·mmHg−1. The diastolic pressure at which coronary flow ceased rose slightly from 13 to 15 mmHg. Intracoronary adenosine completely prevented vasopressin's effect, and the vasodilator response to adenosine was not attenuated by simultaneous administration of vasopressin. The porcine coronary circulation will constrict in response to vasopressin, not only at normal perfusion pressure, but also at low levels when metabolic vasodilatation is intense. Our study has implications about the therapeutic use of vasopressin, and demonstrates interaction of vasoactive stimuli in the coronary circulation.
Membership tests for images of algebraic sets by linear projections

Given a witness set for an irreducible variety V and a linear map @p, we describe membership tests for both the constructible algebraic set @p(V) and the algebraic set @p(V)@?. We also provide applications and examples of these new tests including computing the codimension one components of @p(V)@?@?@p(V)@?. Additionally, we also describe computing the geometric genus of a curve section of an irreducible component of the solution set of a polynomial system and a test for deciding whether a plane quartic curve is a Luroth quartic.
Structure and composition of an oak-hickory forest after over 60 years of repeated prescribed burning in Missouri, U.S.A

Abstract Prescribed fire is often used in upland oak forests to achieve objectives related to woodland restoration or oak regeneration. While not uncommon for prescriptions to include repeated burning at short fire return intervals, long-term frequent fire effects in hardwood forests have rarely been quantified. We describe the effects of over 60 years of repeated prescribed burning on stand structure and composition in a Missouri Ozark oak-hickory forest. Data were collected in 2010 and 2013 from 40 × 40 m plots arranged in a randomized complete block design with two blocks and three treatments: an unburned control (Control), annual prescribed fire (Annual; one-year fire return interval), and periodic prescribed fire (Periodic; four-year fire return interval). In 2013, the diameter distribution of the Control was an exponential decay, whereas those in both burn treatments were unimodal. Repeated prescribed burning, especially at four-year fire return intervals, reduced overstory density and canopy cover and shifted overstory composition from a mixture of white oak species, red oak species, and hickories to primarily white oak species. Although small-diameter stems were top-killed on Periodic plots, resprouting created a dense mid-story of small stature saplings. In contrast, Annual plots were virtually void of woody seedlings and saplings. There was no apparent tree recruitment on either Annual or Periodic plots. The abundance, richness, diversity, and evenness of the understory plant community were greater on the burned plots than on the Control plots, with forbs dominating the Annual plots and woody species dominating the Control plots. Periodic plots included a mixture of forbs and woody species, and graminoids were not common in any plots. Understory species richness per square meter was nearly three times greater on both burn treatments relative to the Control. Our results indicate that long-term, repeated prescribed burning can approximate woodland conditions. However, the lack of tree recruitment suggests that periods without fire are critical for replacing overstory trees. Moreover, additional treatments such as mechanical thinning may be important for modifying the understory environment to benefit graminoids or for reaching management objectives on desirable timescales.
Optical computing and image processing using photorefractive gallium arsenide

Recent experimental results on matrix-vector multiplication and multiple four-wave mixing using GaAs are presented. Attention is given to a simple concept of using two overlapping holograms in GaAs to do two matrix-vector multiplication processes operating in parallel with a common input vector. This concept can be used to construct high-speed, high-capacity, reconfigurable interconnection and multiplexing modules, important for optical computing and neural-network applications.
Functional effects of lesion-induced plasticity: Long term potentiation in normal and lesion-induced temporodentate connections

Abstract The crossed temporodentate pathway from the entorhinal cortex of one hemisphere which proliferates in response to a contralateral entorhinal lesion in adult rats was analyzed for its ability to exhibit long term potentiation of synaptic efficacy similar to that which occurs in the normal ipsilateral temporodentate pathway. It was found that while the small synaptic response evoked by contralateral entorhinal cortical stimulation in normal rats does not undergo long term potentiation, after unilateral entorhinal lesions and proliferation of the crossed tempordentate pathway, the crossed pathway acquires a capacity for potentiation of synaptic action which qualitatively resembles that of the normal ipsilateral temporodentate circuit. However, despite the potentiation of synaptic drive, no long term enhancement of cell discharge was observed in the re-innervated dentate gyrus even though potentiation of this parameter was very prominent in the ipsilateral pathway. Mechanisms are discussed by which a previously non-potentiating pathway may acquire, as a consequence of lesion-induced sprouting, an ability to undergo long term potentiation of synaptic efficacy in a fashion similar to the ablated pathway. Reasons for the failure to observe potentiation of cell firing are also considered.
Treatment of IM-9 cells with human growth hormone (GH) promotes rapid disulfide linkage of the GH receptor.

Human GH (hGH) is believed to elicit its signal by promoting dimerization of the hGH receptor (hGHR). In this study, we examined a covalent linkage of receptors induced by hGH treatment of IM-9 cells. hGH induced a time- and concentration-dependent appearance of a disulfide-linked species of 215-230 kilodaltons, designated p215-230, that at 37 C was long-lived (> 1 h). p215-230 was confirmed to contain the hGHR (115-140 kilodaltons) as at least one of its constituents by two-dimensional diagonal sodium dodecyl sulfate-polyacrylamide gel electrophoresis. hGH induction of p215-230 required intact cells and was inhibitable by pretreatment of cells with N-ethylmaleimide (NEM), a sulfhydryl-reactive alkylating agent. NEM pretreatment did not, however, prevent hGH-dependent formation of a nondisulfide-linked p215-230 form, which was detected in NEM-pretreated hGH-stimulated cells by chemical cross-linking of detergent cell extracts. The disulfide-linked form of the hGHR accounted for a substantial fraction of t...
Polyolefin alloys and blends

Blends of polyolefins are reviewed from the perspective of a historic evolution of technology. Blends of polyethylenes, polypropylene, and ethylenepropylene copolymers, with either a commodity, engineering or specialty resin, are discussed.
NIST Gas Hydrate Research Database and Web Dissemination Channel.

To facilitate advances in application of technologies pertaining to gas hydrates, a United States database containing experimentally-derived information about those materials was developed. The Clathrate Hydrate Physical Property Database (NIST Standard Reference Database {number_sign} 156) was developed by the TRC Group at NIST in Boulder, Colorado paralleling a highly-successful database of thermodynamic properties of molecular pure compounds and their mixtures and in association with an international effort on the part of CODATA to aid in international data sharing. Development and population of this database relied on the development of three components of information-processing infrastructure: (1) guided data capture (GDC) software designed to convert data and metadata into a well-organized, electronic format, (2) a relational data storage facility to accommodate all types of numerical and metadata within the scope of the project, and (3) a gas hydrate markup language (GHML) developed to standardize data communications between 'data producers' and 'data users'. Having developed the appropriate data storage and communication technologies, a web-based interface for both the new Clathrate Hydrate Physical Property Database, as well as Scientific Results from the Mallik 2002 Gas Hydrate Production Research Well Program was developed and deployed at http://gashydrates.nist.gov.
Sensitivity analysis for feedforward artificial neural networks with differentiable activation functions

A method for computing the network output sensitivities with respect to variations in the inputs for multilayer feedforward artificial neural networks with differentiable activation functions is presented. It is applied to obtain expressions for the first- and second-order sensitivities. An example is introduced along with a discussion to illustrate how the sensitivities are calculated and to show how they compare to the actual derivatives of the function being modeled by the neural network. >
Upregulated liver conversion of α-linolenic acid to docosahexaenoic acid in rats on a 15 week n-3 PUFA-deficient diet

We quantified incorporation rates of plasma-derived alpha-linolenic acid (alpha-LNA, 18:3n-3) into "stable" liver lipids and the conversion rate of alpha-LNA to docosahexaenoic acid (DHA, 22:6n-3) in male rats fed, after weaning, an n-3 PUFA-adequate diet (4.6% alpha-LNA, no DHA) or an n-3 PUFA-deficient diet (0.2% alpha-LNA, no DHA) for 15 weeks. Unanesthetized rats were infused intravenously with [1-14C]alpha-LNA, and arterial plasma was sampled until the liver was microwaved at 5 min. Unlabeled alpha-LNA and DHA concentrations in arterial plasma and liver were reduced >90% by deprivation, whereas unlabeled arachidonic acid (20:4n-6) and docosapentaenoic acid (22:5n-6) concentrations were increased. Deprivation did not change alpha-LNA incorporation coefficients into stable liver lipids but increased synthesis-incorporation coefficients of DHA from alpha-LNA by 6.6-, 8.4-, and 2.3-fold in triacylglycerol, phospholipid, and cholesteryl ester, respectively. Assuming that synthesized-incorporated DHA eventually would be secreted within lipoproteins, calculated liver DHA secretion rates equaled 2.19 and 0.82 micromol/day in the n-3 PUFA-adequate and -deprived rats, respectively. These rates exceed the published rates of brain DHA consumption by 6- and 10-fold, respectively, and should be sufficient to maintain normal and reduced brain DHA concentrations, respectively, in the two dietary conditions.
Measurement of Local Blood Flow with Hydrogen Gas

When a platinized platinum electrode is polarized at the potential of the standard calomel electrode, the current generated is proportional to the concentration of dissolved hydrogen gas. The effects of physiological variations in oxygen tension, pH, temperature, and ascorbic acid concentration were found to be negligible. Although absolute calibration in vivo is not possible, the rate of tissue hydrogen saturation or desaturation can be measured by needle-shaped electrodes inserted into the tissue. Arterial and venous concentration can be measured with catheter electrodes. Solubility of hydrogen gas in kidney slices was found to be the same as in blood. With the assumption that tissue is in instantaneous diffusion equilibrium with local venous blood with respect to hydrogen, the local blood flow per volume of tissue can be calculated according to the Fick principle from the rate of tissue desaturation when arterial concentration is lowered to zero. The method was tested on dogs in myocardium, kidney, and skeletal muscle. Hydrogen was administered by respiration or by intra-arterial infusion of hydrogen-saturated saline, giving an arterial concentration of 3% to 5% saturation. Tissue desaturation curves were recorded simultaneously from two to three tissue electrodes. Good agreement with flow measured simultaneously with other methods was obtained in myocardium and renal cortex, while the data on skeletal muscle do not permit any definite conclusion. The main virtue of this method lies in the fact that repeated measurements of local blood flow can be obtained without access to arterial or local venous blood. Reliable measurements of regional blood flow were also obtained from continuously recorded venous desaturation curves, which also provide information on the distribution of blood flow.