cssi/SciSciGPT-SciSciNet huggingface dataset:
Receptor-stimulated phospholipase A2 activation is coupled to influx of external calcium and not to mobilization of intracellular calcium in C62B glioma cells

C62B rat glioma cells respond to muscarinic cholinergic stimulation with transient inositol phosphate formation and phospholipase A2-dependent arachidonic acid liberation. Since phospholipase A2 is a Ca2+-sensitive enzyme, we have examined the role of the agonist-stimulated Ca2+ response in production of the arachidonate signal. The fluorescent indicator fura-2 was used to monitor changes in cytoplasmic Ca2+ levels ([Ca2+]i) of C62B cells following acetylcholine treatment. In the presence of extracellular Ca2+, acetylcholine induces a biphasic [Ca2+]i response consisting of an initial transient peak that precedes arachidonate liberation and a sustained elevation that outlasts the phospholipase A2 response. The initial [Ca2+]i peak is not altered by the absence of external Ca2+ and therefore reflects intracellular Ca2+ mobilization. The sustained elevation phase is dependent on the influx of external Ca2+; it is lost in Ca2+-free medium and restored on the addition of Ca2+. Pretreating cells with phorbol dibutyrate substantially inhibits acetylcholine-stimulated inositol phosphate formation and the peak [Ca2+]i response without affecting the sustained elevation in [Ca2+]i. This suggests that the release of internal Ca2+ stores by inositol 1,4,5-trisphosphate can be blocked without interfering with Ca2+ influx. Pretreatment with phorbol also fails to affect acetylcholine-stimulated arachidonate liberation, demonstrating that phospholipase A2 activation does not require normal intracellular Ca2+ release. Stimulated arachidonate accumulation is totally inhibited in Ca2+-free medium and restored by the subsequent addition of Ca2+. Pretreatment with verapamil, a voltage-dependent Ca2+ channel inhibitor, also blocks both the sustained [Ca2+]i elevation and arachidonate liberation without altering peak intracellular Ca2+ release. We conclude that the influx of extracellular Ca2+ is tightly coupled to phospholipase A2 activation, whereas large changes in [Ca2+]i due to mobilization of internal Ca2+ stores are neither sufficient nor necessary for acetylcholine-stimulated phospholipase A2 activation.
Modulation of macrophage interaction with Trypanosomacruzi by phospholipase A2-sensitive components of the parasite membrane

Abstract The presence of phospholipase A2 (PLA2) significantly increased the association between Trypanosoma cruzi and macrophages. This effect reflected alterations to the parasite membrane since it was reproduced only when the parasite but not the macrophage was pretreated with PLA2. That PLA2 activity was responsible for the noted enhancement was indicated by the ability of the specific substrate phosphatidylcholine to block it. The presence of the PLA2 inhibitors quinacrine, 4-bromophenacyl bromide or phentermine markedly inhibited parasite-macrophage association. Quinacrine also inhibited association of the parasite with a non-phagocytic host cell. These results suggested a role for endogenous PLA2 in the initial stages of cell infection by T. cruzi .
Two-Scale Geomechanics of Carbonates

The geomechanical characterization of a carbonate reservoir is required for formation stimulation and hydrocarbon recovery. The pertinent core- or block-scale (large-scale) characterizations are time consuming and expensive, and more importantly, cannot be used for drill cuttings. The present study proposes a two-scale model based on microscale (small-scale) measurements to predict the geomechanical properties of a carbonate formation at the core scale. At the small scale, we develop a physically representative element by accounting for the effective stiffness of a constitutive mineral and of voids. At the large scale, we account for the volume fraction of each mineral, the porosity, and the pore structure of the void space. The elastic deformation of a large-scale model is simulated using a finite element method (FEM), whose results are tested against independent lab measurements. The proposed two-scale model has applications for geomechanical characterization of a formation at the core scale from drill cuttings.
To Bring Math to the World, Start with Mathematicians

The author discusses memorable experiences as Editor of the AMS Notices in popularizing mathematics to mathematicians.
Constrained mixed-integer Gaussian mixture Bayesian optimization and its applications in designing fractal and auxetic metamaterials

Bayesian optimization (BO) is a global optimization method that has the potential for design optimization. However, in classical BO algorithm, the variables are considered as continuous. In real-world engineering problems, both continuous and discrete variables are present. In this work, an efficient approach to incorporate discrete variables to BO is proposed. In the proposed constrained mixed-integer BO method, the sample set is decomposed into smaller clusters during sequential sampling, where each cluster corresponds to a unique ordered set of discrete variables, and a Gaussian process regression (GP) metamodel is constructed for each cluster. The model prediction is formed as the Gaussian mixture model, where the weights are computed based on the pair-wise Wasserstein distance between clusters and gradually converge to an independent GP as the optimization process advances. The definition of neighborhood can be flexibly and manually defined to account for independence between clusters, such as in the case of categorical variables. Theoretical results are provided in concert with two numerical and engineering examples, and two examples for metamaterial developments, including one fractal and one auxetic metamaterials, where the effective properties depend on both the geometry and the bulk material properties.
Desert Bloom?: Lessons from Two Decades of Arizona Charter Schooling:

For decades, scholars and politicians have debated the likely impacts of school choice. Yet few have studied the nation's largest state-level charter school market, Arizona, whose 20-year-old chart...
Scientific Ontology: Integrating Naturalized Metaphysics and Voluntarist Epistemology

Scientific Ontology offers a combination of a naturalist approach to scientific ontology and a voluntarist approach. In the first part of this review, I will present a descriptive overview of the b...
Fibrinopeptide A in acute leukemia: relationship of activation of blood coagulation to disease activity

Plasma fibrinopeptide A (FPA) levels were determined in 20 unselected adult patients with acute nonlymphocytic and lymphocytic leukemia. The mean FPA level in patients with active disease (15.0 ng/ml) was significantly higher than during clinical remission (2.4 ng/ml, p less than 0.01). Elevated FPA levels were observed in patients with all morphological forms of acute leukemia. In the group of patients in clinical remission, 20/47 FPA values remained elevated beyond the normal range, suggesting that low-grade intravascular coagulation was present even when no leukemic cells were observed. Sequential studies revealed reduction of FPA levels to the normal range in five patients who entered clinical remission after chemotherapy and rapid elevation of the levels in eight patients who entered relapse after clinical remission. FPA levels rose significantly in five patients studied during induction chemotherapy. Thus, subclinical activation of blood coagulation, as defined by elevation of plasma FPA level, may occur commonly in acute leukemia. Plasma FPA generation may relate to leukemic disease activity.
Retroperitoneal Lymph Nodes: Cytoreduction in a Patient with Ovarian Cancer

Video Objective This video will exemplify the techniques necessary to safely complete a difficult dissection and debulking procedure in the obturator fossa in a patient with high-grade serous fallopian tube carcinoma. Setting This patient is a 67-year-old who presented with a right sided complex adnexal mass and elevated CA-125 of 1300 with concern for malignancy. She was taken to the operating room for laparoscopic right salpingo-oophorectomy with possible hysterectomy and staging. The frozen section was consistent with high-grade serous fallopian tube carcinoma. A bulky retroperitoneal mass was found in the right obturator fossa and the patient underwent debulking procedure. Interventions The patient underwent total laparoscopic hysterectomy, bilateral salpingo-oophorectomy, lymph node dissection, debulking and omentectomy. The bulky retroperitoneal mass was carefully removed using a combination of sharp and blunt dissection, with special care to avoid the nerves and vasculature of the obturator fossa. At the conclusion of the surgery, there was no further evidence of disease. Conclusion In order to properly treat and stage ovarian cancer, a complete staging and debulking procedure must be performed. This video emphasizes the importance of a thorough understanding of retroperitoneal pelvic anatomy and highlights the utilization of impeccable surgical technique to safely perform a pelvic side wall dissection and debulking in the presence of abnormal pathologic findings.
A Case of Widespread Cutaneous Metastases from Esophageal Adenocarcinoma

Cutaneous metastases from internal malignancies are very rare, and only a few cases from esophageal cancer have been reported. We describe the case of a 61-year-old patient with recently diagnosed esophageal adenocarcinoma who presented with multiple skin nodules. Immunohistochemical analysis of the nodules matched the immunohistochemical profile of the patient’s previous esophageal biopsy specimen confirming the diagnosis of cutaneous metastases. This case highlights the importance of including cutaneous metastases in the differential diagnosis of any suspicious lesion in patients with a history of internal malignancy.
A Comparison of Regularized Maximum-Likelihood, Regularized 2-Stage Least Squares, and Maximum-Likelihood Estimation with Misspecified Models, Small Samples, and Weak Factor Structure

Several structural equation modeling estimation methods have recently been developed to alleviate problems associated with model misspecification. Two of the more popular such approaches are 2-stag...
Catalytically Generated Vanadium Enolates Formed via Interruption of the Meyer-Schuster Rearrangement as Useful Reactive Intermediates.

ConspectusEnolate chemistry is one of the most fundamental strategies for the formation of carbon–carbon and carbon–heteroatom bonds. Classically, this has been accomplished through the use of stoi...
A Combination of Deterministic Regularizations and Genetic Algorithms in Two-dimentional Inverse Scattering Problems

The present contribution deals with a reconstruction approach to the inverse electromagnetic scattering problem based on the joint exploitation of the deterministic linear inversion and global optimization strategies. The deterministic approach is based on the Born iterative method (BIM) enhanced by regularization techniques, such as Algebraic Reconstruction Technique (ART) and Conjugate Gradient (CG). In the second step of the overall strategy, a stochastic global optimization approach, the genetic algorithm (GA), is carried out. In this way, we will benefit from the regularization schemes and address the local minima problem. Numerical results are presented with reference to the permittivity reconstructions in the case of a homogeneous cylinder and an inhomogeneous layered cylinder.
Dysfunctionality Hazard Curve: Risk-Based Tool to Support the Resilient Design of Systems Subjected to Multihazards

AbstractWhile resilience metrics have been proposed and studied given a functionality recovery curve, they have not emphasized enough on accounting for the uncertainties in multihazard occurrences ...
Pre-Mortem Percutaneous Femoral Venous Cannulation Significantly Reduces Blood Collection Time and Warm Ischemic Time in Donation after Circulatory Death Heart Procurement

Purpose Successful collection of donor blood in donation after circulatory death (DCD) heart procurement when utilizing the TransMedics organ care system (OCS) is essential. This must be done expeditiously in order to minimize donor organ warm ischemic time as no flush can begin until the donor blood has been collected. This study investigated pre-mortem percutaneous femoral venous cannulation (PFVC) compared to post-mortem right atrial cannulation (RAC) to determine if there would be a reduction in time needed to collect donor blood as well as time to heart flush. Methods We compared time taken to collect 1,800 mL of donor blood and time to heart flush using post-mortem RAC and pre-mortem PFVC in DCD donors. With the RAC technique, the chest was entered expeditiously after the donor progressed and the right atrium was cannulated for donor blood collection. The PFVC technique utilized a femoral venous cannula placed percutaneously pre-mortem and clamped after the donor was systemically heparinized. Once the donor had progressed and procurement was allowed to begin, the cannula was unclamped and blood collection began immediately. The times from incision to completion of blood collection and to heart flush were recorded. Results A total of 8 donors were included in the study. Four donors were assigned to the RAC technique and 4 to the PFVC technique. The two groups were comparable based on age, gender and BMI. They also had similar values of hematocrit. Time to blood collection and time to heart flush were significantly decreased by approximately 110 seconds each in the femoral cannulation group (Table 1). Conclusion Our preliminary data shows that utilization of PFVC in DCD heart procurement significantly reduced time needed to collect the blood volume required as well as reduction in time to heart flush (warm ischemic time). This technique also allowed for immediate decompression of the heart and made prompt entry into the chest easier and safer.
Reactions of coordinated molecules: XX. An unexpected route to the preparation of hydroxycarbenoid and formylrhenium(I) halide complexes

When BrMn(CO)5 and the rhenium complexes, XRe(CO)5 (where X is H, Cl, Br or I) are treated with one equivalent of methyllithium the correspondingcis-halo- or hydrido-acetylmetalate complexes, Li[cis-(OC)4(X)MC(O)CH3], are formed unexpectedly. The protonation of the halo-anions affords the hydroxy-carbenoid complexes. When the halopentacarbonylrhenium complexes are treated with Li[BEt3H] the corresponding formylmetalate complexes are formed. The reaction chemistry of these anions and of the analogous formyl- and acetyl-metalate anion is discussed briefly.
Chapter 8 Electronic and Optical Properties of III–V Nitride based Quantum Wells and Superlattices

Publisher Summary This chapter describes the electronic and optical properties of III–V nitride-based quantum wells and superlattices. Wide bandgap III–V nitrides—such as GaN, AlN, InN—and their alloys exhibit considerable hardness, high thermal conductivity, large bandgap energies, and both conduction and valence band offsets for carrier confinement. Consequently, III–V nitrides are attractive for potential optoelectronic device applications in the blue–green or near ultraviolet spectrum and for high power and high temperature microelectronic devices. The ability to grow alternating thin layers of slightly dissimilar semiconductors, with each individual layer maintaining its crystallinity, results in a modulated conduction band profile along the growth direction. The chapter also emphasizes several discrepancies concerning the determination of some important parameters for the relevant bulk material, such as hole masses, bandgap energy bowing parameters, shear and deformation potentials, and band offsets, which are necessary for determining and understanding laser performance, such as gain and transparency, as well as the performance of electronic devices.
Factors Influencing Stress, Burnout, and Retention of Secondary Teachers.

This study examines the stress, burnout, satisfaction, and preventive coping skills of nearly 400 secondary teachers to determine variables contributing to these major factors influencing teachers. Analysis of Variance (ANOVA) statistics were conducted that found the burnout levels between new and experienced teachers are significantly different, with novice teachers having higher burnout, but their difference in stress levels was not statistically significant. In three multiple regression tests, stress and burnout were found to be statistically significant predictors of job satisfaction; years of experience, job satisfaction, and burnout were statistically significant predictors of stress; and job satisfaction, preventive coping skills, and stress were statistically significant predictors of burnout.
Esophagitis and modified Bernstein tests in infants with apparent life-threatening events.

Objective. The current study was undertaken to determine the prevalence of abnormal intraesophageal pH monitoring, esophagitis, and oxygen desaturation after experimental esophageal acidification (modified Bernstein test) in patients with apparent life-threatening events (ALTEs). Methods. Fifty patients admitted to the hospital with ALTEs were evaluated. Patients underwent 24-hour intraesophageal pH monitoring, esophageal suction biopsies, and modified Bernstein tests to document oxygen desaturation during experimental esophageal acidification. Results. Abnormal pH monitoring was present in 82%, esophagitis in 16%, and oxygen desaturation of at least 5% with experimental esophageal acidification in 22% of the patients. Esophagitis was present in only 3 of 11 patients with oxygen desaturation, which was not different from those patients without oxygen desaturation. Clinical history was not predictive of oxygen desaturation during experimental acidification except that patients with a history of an ALTE while awake were more likely to demonstrate oxygen desaturation with acid. Conclusion. We conclude that 1) the prevalence of oxygen desaturation with experimental acidification in infants with ALTEs is significant and warrants further evaluation; 2) esophagitis is not a necessary predisposing condition to esophageal acid sensitivity in infants with ALTEs; and 3) ALTE while awake are frequently associated with a positive modified Bernstein test.
Accuracy or bias in nurses' ratings of patient compliance: a comparison of treatment modality

ObjectiveThe study examined the accuracy of nurses’ assessments of patient compliance and identified factors influencing these assessments, including possible biases.DesignNurses’ assessments of co...
SENSORY ATTRIBUTES AND CONSUMER ACCEPTANCE OF SWEET POTATO CULTIVARS WITH VARYING FLESH COLORS

The sensory characteristics of sweet potatoes (n = 12 cultivars) with varying flesh color (orange, purple, yellow) and the impact of flesh colors on consumer acceptance were evaluated. A lexicon was developed for sweet potato flavor followed by consumer acceptance testing conducted with and without blindfold conditions to identify if color or visual cues impacted consumer acceptance. Cluster analysis was performedonoveralllikingscoresfollowedbyexternalpreferencemappingtoidentifythedriversoflikingforsweetpotatoes.Thelexicondifferentiatedsweetpotatoes. Appearance (visual appearance) positively impacted liking scores of products that were not well liked but had a lower impact on liking when the sweet potato was well liked suggesting that flavor and texture were the driving attributes for liking. Three consumer clusters were found for overall liking. All clusters liked smooth texture, brown sugar and dried apricot flavor and sweet taste and disliked bitter, umami, astringent mouthfeel,vanilla aroma and residual fibers.Clusters were differentiated bythelikingof visualmoistnessandcolorhomogeneity,whitepotato,cannedcarrot and dried apricot flavors, chalky, firmness, denseness and fibrous texture. Sweet potatoeswithunfamiliarcolorswereacceptedbyallconsumersbutdifferentsensory characteristics appealed to different consumer groups.
DOUBLY ALLYLIC HYDROPEROXIDE FORMED IN THE REACTION BETWEEN STEROL 5,7‐DIENES AND SINGLET OXYGEN

Ergosterol and 7-dehydrocholesterol, common 5,7-conjugated diene sterols, react with photochemically produced singlet oxygen very efficiently to yield, in parallel pathways, the corresponding 5,8-endoperoxides and the 7 beta-hydroperoxy-5,8(9),22-trienol or -5,8(9)-dienol, respectively. The hydroperoxides decompose in an acid-catalyzed reaction to generate hydrogen peroxide and the 5,7,9(11),22-tetraenol or 5,7,9(11) trienol, respectively, with 1:1 stochiometry. The molar ratio of endoperoxide to hydroperoxide was constant (16:5) with two different reaction solvents, two different photosensitizers, and at all time points between 5 min and 3 h from the start of irradiation. Ergosterol did not react with either hydrogen peroxide or superoxide ion under our reaction conditions. Inhibition studies with nitrogen, 2,5-dimethylfuran, beta-carotene, and tert-butanol confirmed the involvement of singlet oxygen in these reactions. The unstable hydroperoxide would be expected to have undesirable biological consequences if formed in vivo.
Application of nonlinear sampling schemes to COSY-type spectra.

Nonlinear sampling along the t1 dimension is applied to COSY-type spectra. The sine dependence of the time domain signals for the cross peaks is matched by a nonlinear sampling scheme that samples most densely around the maximum of the sine function. Data are processed by maximum entropy reconstruction, using a modified implementation of the ‘Cambridge’ algorithm of Skilling and Bryan. The procedure is demonstrated for P.E.COSY spectra recorded on a cyclic hexapeptide and on a 126-residue domain of the protein villin. The number of t1 values in the nonlinearly sampled experiments was reduced by a factor of four compared to linear sampling. The sensitivity and resolution of the resulting spectra are comparable to those achieved by conventional methods. The method described can thus significantly reduce the measuring time for COSY-type spectra.
Moving towards efficient therapies in type 1 diabetes: to combine or not to combine?

Every year, thirty thousand people worldwide are diagnosed with type 1 diabetes mellitus (T1DM). T1DM, also called autoimmune diabetes, is a multifactorial disease affecting predisposed individuals and involving genetic susceptibilities, environmental triggers, as well as unbalanced immune responses. Auto-reactive T cells, produced during the pathogenesis, play an important role by specifically destroying the pancreatic insulin-producing beta-cells in the islets of Langerhans. Numerous therapeutic interventions have been tested, mostly in animal models, but also in humans. To date, only three phase II/III clinical trials have demonstrated safety and efficacy: anti-CD3 antibody, DiaPep277, and GAD65 (in patients with latent autoimmune diabetes in adults). Unfortunately, a significant number of patients did not respond positively and remained insulin-dependant after completion of therapy. Several reasons account for this. Firstly, the severity of the disease as well as the auto-aggressive T cell repertoire vary from patient to patient leading to a broad range of therapeutic efficacies, and secondly at the time of the treatment the number of remaining beta-cells will directly impact the level of insulin production post-treatment. In this review, we will provide some clues to enhance efficacy of future immuno-interventions in patients with T1DM. We suggest that combination therapies might be the best approach.
Short-term endproducts of sulfate reduction in a salt marsh: Formation of acid volatile sulfides, elemental sulfur, and pyrite☆

Abstract Rates of sulfate reduction, oxygen uptake and carbon dioxide production in sediments from a short Spartina alterniflora zone of Great Sippewissett Marsh were measured simultaneously during late summer. Surface sediments (0–2 cm) were dominated by aerobic metabolism which accounted for about 45% of the total carbon dioxide production over 0–15 cm. Rates of sulfate reduction agreed well with rates of total carbon dioxide production below 2 cm depth indicating that sulfate reduction was the primary pathway for sub-surface carbon metabolism. Sulfate reduction rates were determined using a radiotracer technique coupled with a chromous chloride digestion and carbon disulfide extraction of the sediment to determine the extent of formation of radiolabelled elemental sulfur and pyrite during shortterm (48 hr) incubations. In the surface 10 cm of the marsh sediments investigated, about 50% of the reduced radiosulfur was recovered as dissolved or acid volatile sulfides, 37% as carbon disulfide extractable sulfur, and only about 13% was recovered in a fraction operationally defined as pyrite. Correlations between the extent of sulfate depletion in the marsh sediments and the concentrations of dissolved and acid volatile sulfides supported the results of the radiotracer work. Our data suggest that sulfides and elemental sulfur may be major short-term end-products of sulfate reduction in salt marshes.
Staging encounters: The touch of the medieval Other

Shuttling back and forth from medieval to modern texts, this essay proposes an alternative vision of temporality and, in doing so, offers a glimpse into a queer (or non-normative) temporality. The purpose of this temporal travel is to reveal the systems deployed in constructing an outcast, a thing of hate and derision. This essay discusses a select number of medieval texts as the starting point for reflecting on the process involved in inventing a temporal outcast. The conversation about normative temporality mostly builds from The Passion of the Christ, which in this essay represents the end point in meditating on the making of a fantastical Other who materializes from fantasy as a thing outside time and humanity.
Thromboxane modulating agents. 4. Design and synthesis of 3-(2-[{(4-chlorophenyl)sulfonyl}amino]ethyl)benzenepropanoic acid derivatives as potent thromboxane receptor antagonists

Abstract The design of a series of thromboxane receptor antagonists based on 3-(2-[{(4-chlorophenyl)sulfonyl}amino]ethyl)benzenepropanoic acid ( 1 ) is described. Addition of an arylmethyl group at the 5-position of 1 gave exceptionally potent agents in vitro and in vivo , with 13a (UK-147,535) giving complete blockade of the TxA 2 receptor for greater than 12 hours in dogs, following an oral dose of 0.1 mg/kg.
Catalysis of the Rochow Direct Process

Abstract The synthesis of dimethyldichlorosilane by the “Direct Process” is at the heart of the silicone industry. The Direct Process has been the object of intensive research and development over the past 40 years, yet there are aspects of the reaction that remain in an elementary state of understanding. The goal of this work was the discovery of previously unknown variables, including trace elements, which affect product distribution and rate. Fluidized and stirred bed reactors were used. Trace quantities of tin were found to affect the Direct Process profoundly, and the effects of tin and zinc were synergistic. A catalyst system consisting of copper, zinc, and tin was discovered which yielded 90% dimethyldichlorosilane with nearly complete silicon utilization. This is a major improvement over the best previously reported performance.
Active stiffeners for shape and vibration control of circular plate structure

In high precision space optical systems, it is critical that the structure maintains a near-perfect surface. Previous studies investigated the performance of utilizing piezoelectric ceramic patches for reducing the surface error. The research results demonstrated that the two-dimensional actuation effect of the actuator patches could induce high order modal deformations and cause undesired surface error. It was discovered that decoupling the circumferential and radial actuations of the sheet actuators could improve the system performance. To realize the decoupling effect, an active stiffener design is proposed and analyzed in this paper, where a standoff layer is inserted between the host structure and the piezoelectric ceramic sheet actuator. The stiffener acts as a decoupling mechanism which reduces the transmitted action in one direction while allowing adequate action to be transmitted in the orthogonal direction. For the analysis, a 3-D solid finite element model of a thin circular structure containing stiffeners and piezoelectric ceramic actuators is developed. It is shown that the active stiffener design achieves a smoother surface, corrects for more surface error, reduces controller spillover, and improves system stability.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Disruption of reverse micelles and release of trapped ribonuclease A photochemically induced by Malachite Green leuconitrile derivative

Photoinduced disruption of a sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelle is triggered by a Malachite Green leuconitrile derivative (MGL). UV irradiation of MGL solubilized in an AOT-water-chloroform mixture creates a cationic surfactant that interacts electrostatically with the anionic AOT. We investigated the disruption of the reverse micelle by using proton nuclear magnetic resonance spectroscopy and found that UV irradiation of MGL decreases the number of water molecules solubilized in the interior of the AOT reverse micelles. Furthermore, the photoinduced disruption of the reverse micelle is shown to release ribonuclease A, which is trapped in the water in the interior of the AOT reverse micelle. This photoinduced release may offer a desirable transport system of biopolymers.
Some Aspects of Forecasting Severe Thunderstorms during Cool-Season Return-Flow Episodes

Abstract Historically, the Gulf of Mexico has been considered a primary source of water vapor that influences the weather for much of the United States east of the Rocky Mountains. Although severe thunderstorms and tornadoes occur most frequently during the spring and summer months, the periodic transport of Gulf moisture inland ahead of traveling baroclinic waves can result in significant severe-weather episodes during the cool season. To gain insight into the short-range skill in forecasting surface synoptic patterns associated with moisture return from the Gulf, operational numerical weather prediction models from the National Meteorological Center were examined. Sea level pressure fields from the Limited-Area Fine-Mesh Model (LFM), Nested Grid Model (NGM), and the aviation (AVN) run of the Global Spectral Model, valid 48 h after initial data time, were evaluated for three cool-season cases that preceded severe local storm outbreaks. The NGM and AVN provided useful guidance in forecasting the onset of ...
Intraoperative duplex ultrasonography as an adjunct to technical excellence in 100 consecutive carotid endarterectomies.

Abstract Purpose To evaluate the relationship of intraoperative duplex ultrasonography (duplex) results to neurologic outcomes and restenosis among patients undergoing carotid endarterectomy (CEA). Methods One hundred consecutive CEAs were performed at a military medical center over 28 months. Prospectively acquired demographics, duplex results, revisions, and surgical outcomes were reviewed. Results Thirty-four percent (34 of 100) of sites were abnormal by completion duplex. Of these, 70% (24 of 34) were B-mode flap type defects located in the common carotid artery (CCA), internal carotid artery (ICA), or external carotid artery (ECA). Twenty-one percent of the defects (7 of 34) were technically unacceptable and immediately revised. Subsequently, 3 perioperative neurologic events occurred, 2 strokes and 1 transient ischemic attack (TIA), all among patients with an identified but unrepaired defect involving the ICA or CCA. This association of unrepaired defect with early stroke or TIA was significant ( P = 0.02). No significant association ( P >0.05) between unrepaired defects and late ipsilateral stroke or TIA or restenosis was identified. Conclusions Intraoperative duplex scanning is a useful adjunct to CEA that can identify correctable mechanical problems. Residual elevated velocities or B-mode flaps 2 mm or greater in the ICA warrant consideration for immediate repair. Findings not requiring revision include flaps
Gelatin models for photoelastic analysis of gravity structures

The potential of gelatin as a highly sensitive photoelastic material has long been known but seldom utilized. This paper describes a series of tests to show that body-force stress distributions can be conveniently found with gelatin models. Problems arising from the extreme variability of gelatin, including edge dehydration and bacterial attack which have plagued investigators in the past, may be overcome or even turned to advantage by careful control of the mixture and simultaneous calibration. Previous work with gelatin in this country and abroad has been reviewed in order to indicate the available information on the instantaneous physical and optical properties. Data from the calibration test performed at Princeton were used to obtain both the instantaneous and the linearly viscoelastic creep behavior of the gelatin mixture chosen in terms of constant moduli which can be compared with other time-dependent, prototype materials. Apparatus and procedure for both calibration and model tests are outlined, and test results for one of the wedge-shaped gravity structures investigated are compared with analytic predictions.
The Texas Coastal Rainstorm of 17–21 September 1979: An Example of Synoptic Mesoscale Interaction

Abstract A case study is made of the Texas coastal rainstorm of 17–21 September 1979 in which upward of 50 cm of rain inundated the area. The precipitation developed along a weak baroclinic zone left in place by a trough passage at higher latitudes. A cold upper tropospheric vortex over the southwestern United States enabled relatively cooler and drier air to flow southward over the warmer waters of the western Gulf of Mexico. Differential heating and moistening along a Texas coastal front slowly destabilized the atmosphere and set the stage for a convective scale response. A mesoscale cyclonic circulation formed near the southwestern end of the coastal front and along the western edge of a convective cloud cluster. Embedded within this circulation was a short-lived mesocyclone which achieved tropical storm strength for 12 h. The case is a specific example of a mesoscale circulation in which origin and evolution is controlled by synoptic scale patterns. The mesocale disturbance, once formed, moves northea...
Orientation of Phospholamban in Lipid Bicelles Detected by Electron Paramagnetic Resonance

We have used electron paramagnetic resonance (EPR) to probe the structural dynamics of the integral membrane protein phospholamban (PLB), as a function of phosphorylation and addition of its regulatory target, the sarcoplasmic reticulum calcium ATPase (SERCA). We found previously that PLB remains bound to SERCA after phosphorylation, suggesting that a structural transition within the SERCA-PLB complex is responsible for relief of inhibition. Our current goal is to elucidate this mechanism through orientation and accessibility EPR, in order to support rational design of therapies to improve calcium transport in muscle cells. We used the monomeric mutant AFA-PLB, with the rigid electron spin label TOAC incorporated within the transmembrane domain, and reconstituted the protein in lipid bicelles and vesicles. EPR showed that the accessibilities of PLB spin labels to paramagnetic relaxation agents changed upon phosphorylation, indicating vertical (parallel to the membrane normal) movement of PLB. EPR on aligned bicelles showed that PLB changes its tilt relative to the membrane upon phosphorylation. Results will also be reported on structural changes in the presence of SERCA. This work was funded by grants from NIH (R01 GM27906 and T32 AR007612).View Large Image | View Hi-Res Image | Download PowerPoint Slide
On the matrix Riccati equation of transport processes

Abstract By keeping count of the number of interactions, we obtain some novel perturbation expansions for the Riccati equation. Similar results were obtained in radiative transfer theory by Mingle.
Double-membraned liposomes sculpted by poliovirus 3AB protein.

Infection with many positive-strand RNA viruses dramatically remodels cellular membranes, resulting in the accumulation of double-membraned vesicles that resemble cellular autophagosomes. In this study, a single protein encoded by poliovirus, 3AB, is shown to be sufficient to induce the formation of double-membraned liposomes via the invagination of single-membraned liposomes. Poliovirus 3AB is a 109-amino acid protein with a natively unstructured N-terminal domain. HeLa cells transduced with 3AB protein displayed intracellular membrane disruption; specifically, the formation of cytoplasmic invaginations. The ability of a single viral protein to produce structures of similar topology to cellular autophagosomes should facilitate the understanding of both cellular and viral mechanisms for membrane remodeling. Background: Poliovirus induces formation of double-membraned vesicles as the site of viral replication in infected cells. Results: The membrane-associated protein 3AB alone produces double-membraned liposomes by invagination of purified liposomes and intracellular membranes. Conclusion: A single poliovirus protein produces membrane remodeling similar to the formation of autophagosomes. Significance: Similar cellular processes are critical for autophagy, multivesicular body formation, unconventional secretion, and viral pathogenesis.
Reversible lithium insertion in the garnet framework of Li3Nd3W2O12

Abstract Insertion into the garnet Li3Nd3W2O12 of four Li per formula unit shows excellent reversibility. The W sites share edges with Nb sites, but they are isolated from one another, so the W-5 d electrons remain strongly correlated with the W(V)/W(IV) redox energy at 0.8–0.85 eV and the W(VI)/W(V) at 0.4–0.55 eV below Li+/Li. Different Li+-ion orderings in the interstitial space are able to keep up with the Li insertion to a 0.2 °C rate, but not to a 0.5 °C rate. A reversible capacity fades at 1 °C rate is attributed mainly to the poor electronic conductivity of the garnet.
Evaluating Task Modification as an Objective Measure of Functional Limitation: Repeatability and Comparability

Background Modification of everyday tasks in older adults is associated with risk of deleterious health outcomes. The purpose of this study was to develop a task modification scale to examine its reliability and comparability to timed performance and common measures of physical function and impairment. Methods Eighty-two (21 men, 61 women) older adults (74.4 +/- 8.2 years) were observed performing a chair rise (sitting heights: 43 cm, 38 cm, and 30 cm), stair ascent/descent, and kneel and supine rise tasks. Six hierarchically ranked categories (0-5) of modification were created for each task and then summed across tasks (summary modification [MOD] score: range 0-35). Comparisons were made with timed performance, knee extension strength, single-leg balance, self-reported function, five chair stands, and gait speed. Results Inter-rater reliability (intra-class correlation = 0.98) and participant repeatability (intra-class correlation = 0.92) of the MOD score were excellent. Ninety-six percent of participants modified at least one task (MOD score: 10.5 +/- 7.51, range 0-27). After adjusting for task modification, timed performance showed a lower association with gait speed (time vs MOD score, semipartial r2 = 0.31 vs 0.68), strength (semipartial r2 = 0.14 vs 0.65), and single-leg balance (semipartial r2 = 0.10 vs 0.40) than did the MOD score. The MOD score showed higher correlations with muscle strength and balance impairment than did other measures of functional limitation such as gait speed, time to complete five chair stands, and self-reported physical function. Conclusion Documentation of task modification is reliable across raters and repeatable within participants; in addition, it compares well with other measures of physical function and impairment. Task modification reveals important and intuitive information regarding physical limitation, and deserves greater attention.
Coordinates which diagonalize the kinetic energy of relative motion

The most general sets of coordinates which diagonalize the relative kinetic energy of an N particle system are derived. These include reaction coordinates which are symmetric with respect to both the reactants and products. The angle of skewing of an idealized potential energy surface determines whether a molecular collision is adiabatic or leads to an exchange reaction. The shape of the potential energy surface leads to vibrationally excited diatomic molecules as products in hydrogen-halogen reactions.
Adolescent parenthood, economic issues, and social policies.

Adolescent parenthood has highly publicized adverse social and economic consequences, but these same social and economic disadvantages can be viewed as root causes of adolescent pregnancy. Recent research and “revisionist” debates about these issues are reviewed and summarized. Diverse implications for social policy are considered. Prevention approaches are emphasized that build on both postponing adolescent sexual intercourse and helping sexually active teens avoid pregnancy.
A model and temporal proof system for networks of processes

A model and a sound and complete proof system for networks of processes in which component processes communicate exclusively through messages is given. The model, an extension of the trace model, can describe both synchronous and asynchronous networks. The proof system uses temporal-logic assertions on sequences of observations — a generalization of traces. The use of observations (traces) makes the proof system simple, compositional and modular, since internal details can be hidden. The expressive power of temporal logic makes it possible to prove temporal properties (safety, liveness, precedence, etc.) in the system. The proof system is language-independent and works for both synchronous and asynchronous networks.
The effects of Su-5879 (esidrix) in congestive heart failure and hypertension: a clinical evaluation.

Abstract 1. 1. Su-5879 (hydrochlorothiazide, Ciba) has been demonstrated to be an effective diuretic of low toxicity in studies on 19 hospitalized and 17 outclinic patients in congestive heart failure. 2. 2. The diuretic effect is similar to that of the mercurials and chlorothiazide, in that there results mainly an outpouring of sodium and chloride, with a decrease in the levels of chloride and an increase of CO 2 in the serum. 3. 3. A single dose of 200 mg. produces a conspicuous diuresis within about 2 hours after ingestion, and this is maintained for over 24 hours. Effective diuresis can also be achieved by doses of 50 mg. administered twice daily. 4. 4. Excretion of potassium was increased moderately, and in a few patients levels of serum potassium below 4.0 mEq./liter appeared after 1 week of therapy. However, only one patient in our series had clinical symptoms of hypopotassemia. 5. 5. Slight elevations in blood urea nitrogen after therapy were observed in some of our patients in congestive heart failure. None developed serious renal insufficiency. If oliguria develops and the blood urea nitrogen rises under treatment, the drug should be withdrawn. 6. 6. Significant reductions in blood pressure occurred in 18 of 26 hypertensive patients. The antihypertensive action of Su-5879 appears most promising. 7. 7. Su-5879 produced no serious complications in our cases. However, the resulting low values for serum potassium in a few of our patients, and the occasional moderate rises in values of blood urea nitrogen would, as with chlorothiazide, call for caution in long-term therapy.
Maternal-fetal immune interactions and the maintenance of major histocompatibility complex polymorphism in the rat

In several different strain combinations of rats, an R2 backcross was used to assess the relative fitness of progeny MHC-incompatible with their mothers as compared to that of MHC-compatible progeny. None of the various treatments used to alter maternal immunoregulatory processes, namely splenectomy, active or adoptive immunization, or the induction of transplantation tolerance, was able to perturb consistently the population distribution of RT1 antigens. Though the extreme variability of RT1 heterozygote excess remains poorly understood, studies of parity-associated changes in the population distribution of RT1 heterozygotes: RT1 homozygotes nonetheless do support the hypothesis that the spleen is important to the immunoregulatory control of these phenomena.
Pathways for intracellular generation of oxidants and tyrosine nitration by a macrophage cell line.

Two transformed murine macrophage cell lines (RAW 264.7 ATCC TIB-71 and CRL-2278) were examined for oxidant production at various times following activation by using a set of fluorescence and ESR-active probes. Stimulation with a soluble agonist or activation with bacterial lipopolysaccharide plus γ-interferon caused only very small initial increases in O2 consumption above basal rates; however, at 2-4 h post-activation, respiration increased to 2-3 fold and remained at these elevated levels over the subsequent lifetime of the cell (20-30 h). Oxidation reactions were confined primarily within the cell, as was demonstrated by using phagocytosable dichlorodihydrofluorescein-conjugated latex beads and cyclic hydroxylamines with differing membrane permeabilities. From the intrinsic reactivities of these probes and the time course of their oxidations, one infers induction of apparent peroxidase activity beginning at ∼2 h post-activation, coinciding with the increase in overall respiratory rate; this acquired capability was accompanied by accumulation of a stable horseradish peroxidase-reactive oxidant, presumably H2O2, in the extracellular medium,. Nitrite ion rapidly accumulated in the extracellular medium over a period of 5-8 h post-activation in both cell lines, indicating the presence of active nitric oxide synthase (iNOS) during that period. Prostaglandin endoperoxide H synthase (COX-2) activity was detected at 15-20 h post-activation by use of sensitive peroxide assay in conjunction with a COX-2 specific inhibitor (DuP-697). Superoxide formation was detected by reaction with hydroethidine within the first hour following activation, but not thereafter. Consistent with the absence of significant respiratory stimulation, the amount of O2 ·- formed was very small; comparative reactions of cyclic hydroxylamine probes indicated that virtually none of the O2 ·- was discharged into the external medium. Myeloperoxidase (MPO) activity was probed at various times post-activation by using fluorescein-conjugated polyacrylamide beads, which efficiently trap MPO-generated HOCl in neutrophils to give stable chlorofluorescein products. However, chlorination of the dye was not detected under any conditions in RAW cells, virtually precluding MPO involvement in their intracellular reactions. This same probe was used to determine changes in intraphagosomal pH, which increased slowly from ∼6.5 to ∼8.2 over a 20 h post-phagocytosis period. The cumulative data suggest activation is followed by sequential induction of an endogenous peroxidase, iNOS, and COX-2, with NADPH oxidase-derived O2 ·- playing a minimal role in direct generation of intracellular oxidants. To account for reported observations of intracellular tyrosine nitration late in the life cycles of macrophages, we propose a novel mechanism wherein iNOS-generated NO2 - is used by COX-2 to produce NO2 · as a terminal microbicidal oxidant and nitrating agent.