cssi/SciSciGPT-SciSciNet huggingface dataset:
Bioassay of crude extracts for the factor that prevents second matings in female Musca domestica.

Extracts of tissues of the house fly, Musca domestica L., were prepared and injected into virgin female flies to study mating inhibition and mortality. A factor that inhibited mating was extracted from the reproductive systems of the male and newly mated female, male abdomens, and male copulatory duct but not from the testes or the reproductive system of virgin females. An extract of the male copulatory duct caused 50% inhibition of mating at a concentration of 4.3 tissue equivalents. An extract of male abdomens was 53% more effective than an extract of the copulatory duct. All extracts were toxic, and toxicity was enhanced by homogenization, sonification, and oxidation. The most effective bioassay procedure resulted when extracts were prepared from unfragmented tissues, and 1 µliter of the extract containing 4 tissue equivalents was injected into the thorax of 3-day-old virgin females; 3 days later the females were tested for mating inhibition.
Organelle-Targetable Fluorescent Probes for Imaging Hydrogen Peroxide in Living Cells via SNAP-Tag Protein Labeling

Hydrogen peroxide (H2O2) is a potent small-molecule oxidant that can exert a diverse array of physiological and/or pathological effects within living systems depending on the timing and location of its production, accumulation, trafficking, and consumption. To help study the chemistry and biology of this reactive oxygen species (ROS) in its native cellular context, we now present a new method for monitoring local, subcellular changes in H2O2 levels by fluorescence imaging. Specifically, we have exploited the versatility of the SNAP-tag technology for site-specific protein labeling with small molecules on the surface or interior of living cells with the use of boronate-capped dyes to selectively visualize H2O2. The resulting SNAP-Peroxy-Green (SNAP-PG) probes consist of appropriately derivatized boronates bioconjugated to SNAP-tag fusion proteins. Spectroscopic measurements of the SNAP-PG constructs confirm their ability to detect H2O2 with specificity over other biologically relevant ROS. Moreover, these ...
A survey of local interstellar hydrogen from OAO-2 observations of Lyman alpha absorption.

The Wisconsin far ultraviolet spectrometer aboard OAO-2 observed the wavelength region near 1216 A for 69 stars of spectral type B2 or earlier. From the strength of the observed interstellar L sub alpha absorption, atomic hydrogen column densities were derived over distances averaging 300 pc away from the sun. The OAO data were compared to synthetic ultraviolet spectra, originally derived from earlier higher resolution rocket observations, which were computer processed to simulate the effects of absorption by different amounts of hydrogen followed by the instrumental blending.
Ovarian cryopreservation and transplantation for fertility preservation for medical indications: report of an ongoing experience.

Objective To assess the indications, safety, utilization, and success of ovarian tissue freezing and transplantation. Design Prospective longitudinal analysis. Setting Academic medical centers. Patient(s) Fifty-nine women who underwent ovarian tissue cryopreservation with a slow freezing technique between May 1997 and March 2008. A follow-up was conducted 36.8 ± 3.6 months after the procedure. Intervention(s) Ovarian tissue harvesting and cryopreservation. Main Outcome Measure(s) Indications, safety, and utilization rates. Result(s) The mean age (± SE) was 26.7 ±1.2 years (range 4–44 years). The majority of patients had either hematologic malignancies (45.7%) or breast cancer (22%). Of these, 57.6% underwent hematopoietic stem cell transplantation. No complications occurred and no histologic evidence of cancer was found in the harvested tissue. The median length of storage was 3.5 ± 0.3 years (0.06–10.5 years). Fifty-six of 59 patients have not yet used their ovarian tissue. The reasons for nonutilization were social/personal, being still under treatment, and death in 54%, 38%, and 8%, respectively. Only three women (5.1%) underwent transplantation, two with the heterotopic (abdominal wall) and one with the orthotopic technique. One woman with a heterotopic transplant conceived spontaneously and delivered. Of the three transplants, one ceased function after 9 months and two are still functioning at up to 7 years follow-up. Conclusion(s) Ovarian tissue harvesting appears to be safe but the experience with ovarian transplantation is still limited due to low utilization. As a result, the true value of this procedure remains to be determined.
Interpreting culture and susceptibility data in critical care: perks and pitfalls.

Problem – The need for immediate, effective antimicrobial therapy in the critical care patient must be tempered by approaches which simultaneously minimize emergence of antimicrobial resistance. Ideally, therapy will successfully resolve clinical signs of infection, while eradicating infecting pathogens such that the risk of resistance is avoided. Increasing limitations associated with empirical antimicrobial choices direct the need for culture and susceptibility data as a basis of therapy. Even so, such in vitro data should be utilized within its limitations. Objectives – To demonstrate the attributes and limitations of patient and population culture and susceptibility (pharmacodynamic) data in the selection of antimicrobial drugs and to demonstrate the design of individualized dosing regimens based on integration of pharmacodynamic (PD) and pharmacokinetic (PK) data. Diagnosis – Limitations in culture and susceptibility testing begin with sample collection and continue through drug selection and dose design. Among the challenges in interpretation is discrimination between pathogens and commensals. Properly collected samples are critical for generation of data relevant to the patient's infection. Data are presented as minimum inhibitory concentrations (MICs). The MIC facilitate selection of the most appropriate drug, particularly when considered in the context of antimicrobial concentrations achieved in the patient at a chosen dose. Integration of MIC data with key PK data yields the Cmax:MIC important to efficacy of concentration-dependent drugs and T>MIC, which guides use of time-dependent drugs. These indices are then used to design dosing regimens that are more likely to kill all infecting pathogens. In the absence of patient MIC data, population data (eg, MIC90) may serve as a reasonable surrogate. Conclusions – Properly collected, performed, and interpreted culture and susceptibility data are increasingly important in the selection of and design of dosing regimens for antimicrobial drugs. Integration of PK and PD data as modified by host and microbial factors supports a hit hard, exit fast approach to therapy that will facilitate efficacy while minimizing resistance.
Screening for Depression in the Postpartum using the Beck Depression Inventory-II: What Logistic Regression Reveals.

Objective: To identify items on the Beck Depression Inventory-II (BDI-II) that best discriminate between clinically depressed and nondepressed postpartum women. Background: Postpartum depression is a serious and widespread health burden, and the BDI-II is commonly used to detect depression in the postpartum. Yet certain depressive symptoms are ‘normative’ sequelae of childbirth, calling into question the discriminative utility of the BDI-II. Methods: We examined the prospective contribution of BDI-II items to identify items that have the strongest relation with clinical postpartum depression. Women with BDI-II scores >12 were invited to participate in a structured clinical interview. A logistic regression was conducted to determine which BDI-II items discriminated between women who were later diagnosed as Depressed (n = 75) and Nondepressed (n = 78). Results: Of the 11 BDI-II items that differed between the two groups, eight represented cognitive/affective symptoms. Results from the logistic regression in...
Huperzine A regulates amyloid precursor protein processing via protein kinase C and mitogen-activated protein kinase pathways in neuroblastoma SK-N-SH cells over-expressing wild type human amyloid precursor protein 695.

Abstract Alpha-secretase (α-secretase), cleaves the amyloid precursor protein (APP) within the amyloid-β (Aβ) sequence, resulting in the release of a secreted fragment of APP (αAPPs) and precluding Aβ generation. We investigated the effects of the acetylcholinesterase inhibitor, huperzine A (Hup A), on APP processing and Aβ generation in human neuroblastoma SK-N-SH cells overexpressing wild-type human APP695. Hup A dose-dependently (0–10 μM) increased αAPPs release. Therefore, we evaluated two α-secretase candidates, a disintegrin and metalloprotease (ADAM) 10 and ADAM17 in Hup A-induced non-amyloidogenic APP metabolism. Hup A enhanced the level of ADAM10, and the inhibitor of tumor necrosis factor-α converting enzyme (TACE)/ADAM17 inhibited the Hup A–induced rise in αAPPs levels, further suggesting Hup A directed APP metabolism toward the non-amyloidogenic α-secretase pathway. Hup A had no effect on Aβ generation in this cell line. The steady-state levels of full-length APP and cell viability were unaffected by Hup A. Alpha-APPs release induced by Hup A treatment was significantly reduced by muscarinic acetylcholine receptor antagonists (particularly by an M1 antagonist), protein kinase C (PKC) inhibitors, GF109203X and calphostin C, and the mitogen-activated kinase kinase (MEK) inhibitors, U0126 and PD98059. Furthermore, Hup A markedly increased the phosphorylation of p44/p42 mitogen-activated protein (MAP) kinase, which was blocked by treatment with U0126 and PD98059. In addition, Hup A inhibited acetylcholinesterase activity by 20% in neuroblastoma cells. Our results indicate that the activation of muscarinic acetylcholine receptors, PKC and MAP kinase may be involved in Hup A–induced αAPPs secretion in neuroblastoma cells and suggest multiple pharmacological mechanisms of Hup A regarding the treatment of Alzheimer’s disease (AD).
Regression analysis of clustered interval-censored failure time data with informative cluster size

Correlated or clustered failure time data often occur in medical studies, among other fields (Cai and Prentice, 1995; Kalbfleisch and Prentice, 2002), and sometimes such data arise together with interval censoring (Wang et al., 2006). Furthermore, the failure time of interest may be related to the cluster size. For example, Williamson et al. (2008) discussed such an example arising from a lymphatic filariasis study. A simple and common approach to the analysis of these data is to simplify or convert interval-censored data to right-censored data due to the lack of proper inference procedures for direct analysis of these data. In this paper, two procedures are presented for regression analysis of clustered failure time data that allow both interval censoring and informative cluster size. Simulation studies are conducted to evaluate the presented approaches and they are applied to a motivating example.
Is Sustainable Adaptation Possible? Determinants of Adaptation on Mount Kilimanjaro

Adaptation is increasingly planned and funded to reduce negative impacts of climate change for vulnerable social groups; however, vulnerable groups have the least capacity to adapt. Adaptation is therefore unlikely to produce socially sustainable or equitable outcomes. Six adaptation processes on Mount Kilimanjaro, Tanzania, are modeled with logistic regression to identify their determinant factors. Most adaptations simply reproduce unsustainable patterns of social vulnerability rooted in unequal access to land and other resource entitlements. A few exceptions are observed, where low costs, widely accessible knowledge, and community groups with cross-scale social networks enabled vulnerable social groups to implement adaptations.
Monoamine levels within the orbitofrontal cortex and putamen interact to predict reversal learning performance.

Background The compulsive and inflexible behaviors that are present in many psychiatric disorders, particularly behavioral addictions and obsessive-compulsive disorder, may be due to neurochemical dysfunction within the circuitry that enables goal-directed behaviors. Experimental removal of serotonin or dopamine within the orbitofrontal cortex or dorsal striatum, respectively, impairs flexible responding in a reversal learning test, suggesting that these neurochemical systems exert important modulatory influences on goal-directed behaviors. Nevertheless, the behavioral impairments present in psychiatric disorders are likely due to subtle neurochemical differences, and it remains unknown whether naturally occurring variation in neurochemical levels associate with individual differences in flexible, reward-directed behaviors. Methods The current study assessed the ability of 24 individual juvenile monkeys to acquire, retain, and reverse discrimination problems and examined whether monoamine levels in the orbitofrontal cortex, caudate nucleus, and putamen could explain variance in behavior. Results The interaction between dopamine levels in the putamen and serotonin levels in the orbitofrontal cortex explained 61% of the variance in a measure of behavioral flexibility but not measures of associative learning or memory. The interaction mirrored that of a hyperbolic function, with reversal learning performance being poorest in either monkeys with relatively low levels of orbitofrontal serotonin and putamen dopamine or in monkeys with relatively high levels of orbitofrontal serotonin and putamen dopamine levels. Conclusions These results support the hypothesis that subcortical and cortical neuromodulatory systems interact to guide aspects of goal-directed behavior, providing insight into the neurochemical dysfunction that may underlie the inflexible and compulsive behaviors present in psychiatric disorders.
Decreased incidence of antiarrhythmic drug efficacy at electrophysiologic study associated with the use of a third extrastimulus

Drug trials during electrophysiologic study were performed in 166 patients with sustained ventricular tachycardia (VT) or ventricular fibrillation. In the first 21 patients (group I), a maximum of two extrastimuli was used. In 145 subsequent patients (group II), drug efficacy was assessed using three extrastimuli if one or two failed to induce VT. The incidence of acute drug efficacy was 15 of 21 (71%) in group I, but only 44 of 145 (30%) in group II (p less than 0.01). To assess the influence of the third extrastimulus on the differing incidence of acute drug efficacy, we examined the 69 group II patients whose VT was initially induced by one or two extrastimuli. Acutely effective agents were identified for 19 of these 69 patients using up to three extrastimuli to define efficacy. In 24 of te 50 patients for whom no effective drug could be found, VT was induced with one or two extrastimuli during all drug trials. In the remaining 26 patients VT could be induced after drug administration only with use of three extrastimuli. If efficacy had been defined using a maximum of two extrastimuli, these 26 patients would have been considered responsive to drug testing. Overall, 45 to 69 (65%) rather than 19 of 69 (28%) would have had a favorable response (p less than 0.001). Fourteen group I patients and 17 group II patients in whom VT was initially induced by one or two extrastimuli received chronic therapy with agents predicted effective during acute drug trials. At 18 months, the cumulative percent of patients free of arrhythmia recurrence by actuarial analysis was 79 +/- 14% in group I and 80 +/- 14% in group II (NS). Use of three extrastimuli during drug trials is associated with a lower incidence of acute drug efficacy. Limited data suggest that prophylaxis against VT induction by three, rather than two, extrastimuli may not be a stronger predictor of chronic efficacy in patients whose VT is initially induced by one or two extrastimuli. Further study is needed to identify optimal pacing methods for antiarrhythmic drug assessment.
Erosion of Low-Carbon Steel by Coal Particles

The erosion of low-carbon steel, in the annealed and water-quenched condition, by coal particles, has been studied as a function of particle size, velocity, and angle of impingement. It was found that both unicrostructures, pearlitic and martensitic, showed a maximum erosion at an angle of impingement of between 20 and 30°. Under all condition of testing, the martensitic structure showed the higher rate of erosion. The coal particles were found to fracture on impact with the steel surfaces. The amount of fracture was found to increase will increased velocity and particle size. Erosion rate was found to increase with decreasing particle size and was related to particle velocity (V) through a power law relationship of the form: E = kVn, where the exponent (n) has valves between 2.6 and 3.7. Scanning electron microscopy studies indicated that only the harder mineral constituents in the coal, such as pyrite and quartz, were responsible for the erosion of the steel. Presented at the 40th Annual Meeting in Las ...
Differential reactivities of fetal and adult human erythrocytes to antisera directed against glycolipids of human erythrocytes.

Summary. The immunological reactivities of fetal and adult erythrocytes to antisera which were directed against globoside, hematoside and lactosylceramide were compared. Fetal erythrocytes showed higher reactivity than adult erythrocytes in agglutination, hemolysis and absorption capacity of antibody when tested with anti-globoside and anti-hematoside. No differential reactivity was found when tested with anti-lactosylceramide. Treatment of adult erythrocytes by trypsin or by neuraminidase resulted in an increase in their reactivity to the same level as that of fetal erythrocytes, but the reactivity of fetal erythrocytes was not greatly affected by enzyme treatment. The results indicate that globosidie and hematosidie groupings of fetal cells are directly exposed on the periphery of cells, while those of mature erythrocytes are masked by ‘sialomucopeptidyl’ groupings, and their reactivities are hampered.
Real-Time Decentralized Articulated Motion Analysis and Object Tracking From Videos

In this paper, we present two new articulated motion analysis and object tracking approaches: the decentralized articulated object tracking method and the hierarchical articulated object tracking method. The first approach avoids the common practice of using a high-dimensional joint state representation for articulated object tracking. Instead, we introduce a decentralized scheme and model the interpart interaction within an innovative Bayesian framework. Specifically, we estimate the interaction density by an efficient decomposed interpart interaction model. To handle severe self-occlusions, we further extend the first approach by modeling high-level interunit interaction and develop the second algorithm within a consistent hierarchical framework. Preliminary experimental results have demonstrated the superior performance of the proposed approaches on real-world videos in both robustness and speed compared with other articulated object tracking methods.
Mode Selectivity and Mirror Misalignment Effects in Unstable Laser Resonators

It is known that single transverse mode operation of an unstable laser resonator can be achieved using large output coupling and large Fresnel number operation. However, it has not been recognized that there is an upper limit on usable Fresnel number, determined by such effects as mirror alignment stability. We have analyzed a variable-reflectivity unstable resonator using mode solutions obtained by Zucker. The differential loss between the lowest order modes leads to conditions on the Fresnel number and the output coupling if single mode operation is to be realized. The Zucker solution is extended by a perturbation analysis to examine mode distortion caused by mirror misalignment. The on-axis intensity in the far field of the laser output is shown to be a sensitive function of mirror misalignment, and the mirror alignment tolerance permitted varies inversely as the Fresnel number. In practice, this places an upper limit on the usable Fresnel number. The results of this theory are shown to be consistent with laser experiments using unstable resonators.
Reduction of stray inductance in power electronic modules using basic switching cells

This paper introduces the concepts of two basic switching cells, P-cell and N-cell, along with their implications in power electronic circuits. The basic switching cells exist in almost every power electronic circuit. To take advantage of these structures, this paper proposes a novel packaging method for power electronics modules. The proposed packaging method uses the basic switching cells as the unit in a module, instead of traditional anti-parallel connection of active switch and diode. This rearrangement can reduce the stray inductance in the current commutation pass; therefore, the performance and reliability of the power device module and the power electronic system can be improved. A conventional phase leg module and a proposed module are modeled. Electromagnetic simulation is carried out to extract the stray inductance from the two modules. Switching behavior under different package parasitics is studied based on Saber simulation.
Simultaneous Single Unit Recording in vitro with a Photoetched Laser Deinsulated Gold Multimicroelectrode Surface

Flat photoetched gold conductors 12 ?m wide and 2 ?m thick, situated on a glass plate and deinsulated at their tips with single 8 ns UV laser pulses, have been utilized to record single unit extra-cellular activity from brain ganglia of the snail Helix pomatia. A fixed array of 36 such conductors, terminating in six rows and six columns in a 0.5 mm x 1 mm area, is capable of monitoring simultaneous single unit activity from numerous neurons. Spike amplitudes of 300?500 ?V are generally observed from the predominant 40 ?m diameter cells of these ganglia. Giant neurons usually produce signal amplitudes of over 3 mV that are simultaneously seen by many electrodes. Signals can be monitored by merely resting a locally desheathed ganglion on the recording area under its own weight in a shallow pool of Ringer. A 10 ?m diameter crater in a 3?4 ?m thick insulation layer has an impedance of 2?4 M?at 1 kHz. The capacitance of this metal electrolyte interface is about 0.5 pF/?m2, suggesting that the UV laser produces a partially colloidal gold surface. With this recessed tip design, simultaneous single unit recording from small neurons appears ensured if electrode impedances are below 4 M?, shunt impedances are above 30 M?, and glia cells are not allowed to reinsulate the end of the gold conductor.
A Stereoselective Approach to the Azaspiro[5.5]undecane Ring System Using a Conjugate Addition/Dipolar Cycloaddition Cascade: Application to the Total Synthesis of (±)-2,7,8-epi-Perhydrohistrionicotoxin†

An efficient stereocontrolled route to the spirocyclic perhydrohistrionicotoxin derivative (±)-2,7,8-epi-PHTx (4) is described. The reaction of 2-butyl-3-(methoxymethoxy)cyclohexanone oxime with 2,3-bis(phenylsulfonyl)-1,3-butadiene gives rise to a 7-oxa-1-azanorbornane cycloadduct in high yield. The formation of the bicyclic isoxazolidine arises from conjugate addition of the oxime onto the diene to give a transient nitrone which then undergoes an intramolecular dipolar cycloaddition. Treatment of the cycloadduct with 5% Na/Hg results in reductive nitrogen−oxygen bond cleavage to furnish an azaspiro[5.5]undecane. Elaboration to the dihydropyridin-4(1H)-one 24 was followed by stereoselective conjugate addition using n-pentyl cuprate to give azaspirocycle 25. The stereochemistry of the product was deduced from an X-ray crystal structure of the corresponding N-tosylhydrazone derivative. The dominant factor controlling the stereochemistry of the conjugate addition is the A(1,3)-strain present in the planar v...
Episodic magma chambers and amagmatic extension in the Josephine ophiolite

Geochemical and structural aspects of the Josephine ophiolite indicate that it formed by alternating cycles of magmatic and structural (amagmatic) extension. Episodic magma chambers are indicated by the presence of very primitive lavas in the lower pillow lavas which would have mixed into a magma chamber. Fe-Ti basalts that occur in the uppermost extrusive rocks and plagiogranites that occur along the sheeted-dike/gabbro contact represent highly fractionated magmas produced during the last stages of crystallization of a magma chamber. During periods of amagmatic extension, breccias accumulated and the entire crustal sequence was tilted >50°, probably by faulting above an upper-mantle detachment. More than 1000 m of uplift and down-dropping between magmatic cycles is suggested by the presence of out-of-place screens in the sheeted-dike complex.
Numerical methods for free-free radiative transition matrix elements

Increasing interest in multiphoton absorption processes above the ionization threshold has led theorists to reexamine numerical techniques for calculating radiative transition matrix elements between states of a continuum electron moving at large radial distances in the field of an atom or an ion. Here it is shown that accurate free—free radial matrix elements may be obtained using the usual dipole length formula by means of a rotation at finite distance in the complex coordinate plane together with solution of the free-electron wave function's phase and amplitude at finite distance in the complex coordinate plane. The procedure is designed for use with numerically calculated wave functions for many electron atoms and ions. It avoids the use of analytic asymptotic formulas as well as transformation to the dipole acceleration formula and is accurate even for matrix elements between electron stales that are close in energy, which is the case for which the alternative integration-by-parts method is inaccurate. We present comparisons of our numerical procedure with both analytic results and results of the integration-by-parts procedure for the case of free—free electron transitions in a pure Coulomb field.
Obstacles in the path of mental health professionals who deal with traumatic violations of human rights

This paper is divided into two parts. The first part, the longer, deals with obstacles in the path of mental health professionals becoming more involved in issues of human rights violations. The second part deals with a few of the increasing number of instances in which mental health professionals have become more involved. These discussions will center around issues involving children, although most of what is said applies to both children and adults. In referring to “human rights” violations, the boundaries between the devastation of large scale wars between nations and within nations (such as the Holocaust and the Cambodian genocide) and the harm done in more narrowly defined “human rights” violations (such as the arrest, torture, and often “disappearance” of thousands in Argentina and Chile) are not exactly clear. For our purposes, the rough working definition of human rights violations includes the devastation wrought by plans to persecute and destroy individuals, classes, ethnic groups or religious sects, independent of the absolute numbers involved. The involvements of mental health professionals to which I refer break down into three main categories. The first is short-term assessment and evaluation (as part of ascertaining the harm done to the victims), often performed in conjunction with human rights and legal investigations. Examples of this category include the role of psychiatrists in evaluating the claims of Holocaust survivors for reparations from the German government (beginning in the 1950s) and the role of mental health professionals in evaluating victims of torture in several Latin American regimes. The second category is the longer term assistance and treatment of victims of human rights violations. This longer term commitment entails different demands, problems, and rewards than the first sort. A third type of involvement occurs when mental health professionals assess large scale situations in which large numbers of people have been damaged. These professionals feed information to governments, relief agencies, and international agencies, hoping the information will affect policy. Examples of this are the pioneering work of John Bowlby (Bowlby, 1951) in surveying the needs of European children in the wake of World War II devastation and the work of Richard Mollica and his co-workers in Cambodian
Endowment Spending Rates, Intergenerational Equity and the Sources of Capital Gains.

Abstract This paper analyzes how James Tobin’s widely cited concept of “intergenerational equity” for university endowments relates to the economic concepts of intertemporal substitutability and risk aversion. I show that Tobin’s concept of intergenerational equity is a very special case of intertemporal substitutability; a special case that implies very low tolerance for risk. Using the more general case, I show that the observed reduction in university spending rates during the 1990s can be viewed as a reasonable response to a period of non-recurring capital gains.
Comments on noise and resolution of the DenOptix radiography system.

Abstract Objectives. Relatively low signal/noise (S/N) ratios, which are not substantiated by the results reported here, have been reported for the DenOptix digital intraoral radiography system. Unexplained poor performance has also been reported for imaging of the gingival tissue. I sought to discover the probable sources of the discrepancies and to present data on the effects of pixel size and screen type on noise and resolution. Methods. S/N ratios were measured with an aluminum phantom, and noise was measured with a step-wedge. The radiographs were scanned with both default and special, manufacturer-supplied software to obtain 8-bit rescaled data and 16-bit raw data. The data were compared with previously published data for the DenOptix and Digora systems. Results. The S/N ratios of up to 17 obtained here were much higher than previously reported. Previously reported low ratios and poor performance for the imaging of gingival tissue were likely caused by digital clipping of 8-bit images, which should not affect bony tissue images in normal clinical radiographs. With nonstandard white phosphor screens, S/N ratios of up to 18 were observed, with only a minor loss of resolution. For the smallest pixel size (42 μm), resolutions of ≥10 line-pairs/mm and ≥8 line-pairs/mm were observed for standard blue and white phosphor screen types. If the smallest pixel size is selected, the noise increases by only 25%, which is much less than the theoretical increase. Conclusions. In terms of both noise and resolution, the DenOptix system compares favorably with the Digora system. S/N ratios for the DenOptix system are comparable with the best of 6 previously tested systems. With the DenOptix system, the smallest pixel size produces both the best resolution and the best noise characteristics. The selection of 16-bit images prevents digital clipping of 8-bit images. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2003;95:746-51)
Reproduction of twentieth century intradecadal to multidecadal surface temperature variability in radiatively forced coupled climate models

[1] Coupled Model Intercomparison Project 3 simulations that included time-varying radiative forcings were ranked according to their ability to consistently reproduce twentieth century intradecadal to multidecadal (IMD) surface temperature variability at the 5° by 5° spatial scale. IMD variability was identified using the running Mann-Whitney Z method. Model rankings were given context by comparing the IMD variability in preindustrial control runs to observations and by contrasting the IMD variability among the ensemble members within each model. These experiments confirmed that the inclusion of time-varying external forcings brought simulations into closer agreement with observations. Additionally, they illustrated that the magnitude of unforced variability differed between models. This led to a supplementary metric that assessed model ability to reproduce observations while accounting for each model's own degree of unforced variability. These two metrics revealed that discernable differences in skill exist between models and that none of the models reproduced observations at their theoretical optimum level. Overall, these results demonstrate a methodology for assessing coupled models relative to each other within a multimodel framework.
Emergency contraception, efficacy and public health impact

PURPOSE OF REVIEW: Emergency contraception in the past two decades had been proven to be effective and well tolerated. Counseling and advance provision and prescription of emergency contraception have been embraced by professional organizations in practice guidelines for its potential to reduce the number of unintended pregnancies and abortions. Has emergency contraception lived up to that promise? RECENT FINDINGS: Mifepristone (not available in the USA) is the agent of choice. Emergency contraception has not reduced the number of unintended pregnancies. Acceptance by healthcare providers and the public has not been optimal and multiple financial and healthcare system barriers to use emergency contraception continue to exist. The public health impact of emergency contraception has been disappointing. SUMMARY: Although emergency contraception may continue to be an important component of contraceptive practice only increased access to more effective methods of contraception will change unintended pregnancy rates. The use of mifepristone for emergency contraception in the USA must be considered.
Helium-oxygen therapy in the emergency department

Helium is an inert gas with unique physical properties that allow it to be used for various respiratory emergencies. Because of its low specific gravity and low viscosity, the passage of helium through the respiratory tract is smoother, more laminar, and less turbulent than either air or oxygen. These properties have prompted the use of helium and oxygen in patients with airway obstructions due to tumor, foreign body, edema, or bronchoconstriction. Helium-oxygen has been used to facilitate bronchoscopy through small diameter endotracheal tubes and to increase the effectiveness of high-frequency jet ventilation. Helium has been successful in the treatment of spinal cord decompression sickness seen in divers. Helium-oxygen mixtures are commercially available and may be useful in the emergency department to treat patients with airway obstruction. This article reviews literature concerning the use of helium-oxygen gas mixtures in the emergency department. Additional research conducted in the future may further define the use of this unique gas mixture in the emergency department.
Nonlinear Optical Interactions In Langmuir-Blodgett Organic Semiconductor Heterostructures

Monolayer and multilayer Langmuir-Blodgett films of two systems: (i) polyalkylthiophene and (ii) tetrakis cumylphenoxy phthalocyanines in pure form and mixed phase with octadecanol were prepared. We report here the first observation of a degenerate four wave mixing signal from a monolayer Langmuir-Blodgett film that of phthalocyanine, due to a large resonant third order optical nonlinearity, x(3) . The effective x(3) behaviors of both phthalocyanine and polythiophene Langmuir-Blodgett films were investigated by time-resolved femtosecond degenerate four wave mixing. The polythiophene Langmuir-Blodgett film when doped with iodine was found to be highly conductive. We have also observed a dramatic reduction of the nonlinear reflectivity as a consequence of iodine doping of polythiophene Langmuir-Blodgett films.
Spearhead Echo and Downburst in the Crash of an Airliner

Meteorological conditions leading to the crash of an airliner short of the runway of a New York airport were studied. Thunderstorm downdrafts much stronger than those measured on the 1946-47 Thunderstorm Project were found. These exceptional downdrafts have been designated as 'downbursts'. The violent cloud systems that produce downburst cells can be identified in the form of forward extensions of radar echoes designed as 'spearhead echoes' which move with unusual speed. The development of downburst cells appears to be tied in with overshooting tops of clouds at the anvil level.
Potassium Depletion and Diastolic Dysfunction

Changes in extracellular potassium concentration affect nearly all aspects of myocardial function. Reductions in potassium concentration alter the resting membrane potential, membrane conductance for sodium and potassium, repolarization time, relative refractory time, and conduction velocity. The arrhythmogenic consequences of these effects of potassium depletion are well recognized by the medical community. However, the potential influence of hypokalemia on mechanical function of the heart has not been as thoroughly appreciated. More than 10 years ago, Fitzovich et al1,2 analyzed changes in left ventricular mechanical function of dogs who were either potassium replete or moderately depleted as a result of 7 days of low-potassium intake together with a high-sodium intake and thiazide diuretics. The depleted dogs had a mean plasma potassium concentration of 3.2 mmol/L. The investigators observed in the depleted dogs significant impairment of both systolic and diastolic function, with the most striking effect noted in peak rate of ventricular filling, reduced by &49% during acute elevation of preload. The same group extended the study to normal volunteers age 22 to 30 years whose cardiac mechanical function was studied noninvasively by echo and Doppler techniques.2,3 Compared with the potassium replete state, during potassium depletion (plasma potassium reduced by 1.0 mmol/L), the peak rate of ventricular filling was …
Minerals Bill introduced in House

A bill that aims to strengthen a national minerals policy and to establish a three-member White-House-level council to coordinate the development of this policy was introduced in the House of Representatives on April 30 by James D. Santini (D-Nev.). Entitled the National Minerals Security Act (NMSA), the legislation, if passed, also would amend tax laws to assist the mining industry to make capital investments to locate and produce strategic minerals; it would provide the means for the Secretary of the Interior to make withdrawn public lands available for mineral development; and it would create a revolving fund for the sale and purchase of strategic minerals. Santini estimates that 4 billion tons of minerals are needed annually to sustain the nation's economy. Much of the minerals are supplied by other nations, however; Santini wants to see an end to the United States' dependence on foreign countries, especially those that seem relatively unstable politically. ‘The U.S. has placed its national security in the hands of a few foreign nations,’ Santini said in a recent press conference. ‘We are heavily dependent on the region of southern Africa for 76% of our cobalt, 93% of our platinum, 48% of our chromium, and a host of other strategic and critical minerals. Without these minerals, we cannot build jet aircraft, weapons, or other military hardware vitally important to our national security.’
Should Dialysis Patients Ever Receive Warfarin and for What Reasons

It has been common practice for dialysis patients with problematic vascular access to receive warfarin for the purposes of keeping the access functional. This, of course, increases the risk for bleeding. Also, in light of new knowledge, vascular calcification may be enhanced by warfarin (1). Therefore, a reexamination of this common practice seems warranted because the efficacy of anticoagulation for access maintenance has never been established. The available evidence does not allow an evidence-based approach. Therefore, this article is an opinion, based on what is published. The issue obviously warrants a prospective study because the clinical practice is widespread. The most common indication for prescribing warfarin in hemodialysis patients is to maintain vascular access. In dialysis patients with comorbid rhythm disturbances such as atrial fibrillation or patients with prosthetic valves, warfarin may be indicated to prevent stroke. The benefit/harm ratio for this indication needs to be considered separately because the efficacy of warfarin to prevent thromboembolism is well established. A small percentage of warfarin use in ESRD is in patients who have documented hypercoagulable states. The major risk of warfarin in dialysis patients obviously is bleeding, adding to the already present uremic platelet dysfunction that accompanies progressive chronic renal disease. Another major issue regarding warfarin use in dialysis patients is potential bleeding in the event of unplanned or emergency surgery, such as in patients who are awaiting deceased-donor renal transplant. In these cases, surgery may be necessary before the warfarin can be withdrawn. In this situation, even fresh-frozen plasma and vitamin K do not fully reverse the patient’s anticoagulation. In the general population, a rare complication of warfarin is dramatic skin necrosis, presumably as a result of vitamin K deficiency. Risk factors for this adverse reaction are proteins C and S deficiencies and diffuse vascular disease. Because protein S frequently …
TCR transgenic CD8+ T cells activated in the presence of TGFβ express FoxP3 and mediate linked suppression of primary immune responses and cardiac allograft rejection

Although CD4+CD25+FoxP3+ regulatory T cells play a role in allograft tolerance, the role of CD8+ cells with immunosuppressive function is less clear. To address this issue, spleen cells from Rag-1-deficient TCR transgenic (Tg) mice expressing a receptor for ovalbumin (OVA) in the context of MHC class I (OT1) were activated with OVA expressing antigen-presenting cell (APC) in the presence or absence of exogenous transforming growth factor beta (TGFbeta). TGFbeta inhibited the expression of IFN-gamma, granzyme B and the lytic activity of the OT1 T cells while inducing FoxP3 expression in 5-15% of the cells. By contrast, FoxP3 expression was not detected in naive OT-1 T cells or OT-1 T cells activated without exogenous TGFbeta. TGFbeta-activated OT1 cells inhibited the activation of Kd-specific CD8+ CTL responses by normal B6 T cells and the proliferation by Kd-specific CD4+ TCR Tg T cells, but only if the OVA epitope was co-expressed by Kd+ APC. This antigen-specific inhibitory activity, referred to as linked suppression, was neither mediated by residual lytic activity within the activated OT1 T cells nor did it depend upon IL-10 or TGFbeta. Suppression correlated with inhibition of CD86 expression on CD11c+ APC. TGFbeta-activated OT1 T cells also delayed the rejection of heterotopic, vascularized cardiac allografts mediated by anti-Kd-specific CD4+ TCR Tg T cells, but only if the cardiac allograft expressed both OVA and Kd as transgenes. Prolonged survival of allografts was associated with rapid migration of the FoxP3+ OT1 T cells into the donor heart raising the possibility that suppression may be mediated within the allograft. These data show that TGFbeta-activated CD8+ T cells mediate antigen-specific, APC-focused patterns of suppression in vitro and in vivo.
Efficient character-level taint tracking for Java

Over 80% of web services are vulnerable to attack, and much of the danger arises from command injection vulnerabilities. We present an efficient character-level taint tracking system for Java web applications and argue that it can be used to defend against command injection vulnerabilities. Our approach involves modification only to Java library classes and the implementation of the Java servlets framework, so it requires only a one-time modification to the server without any subsequent modifications to a web application's bytecode or access to the web application's source code. This makes it easy to deploy our technique and easy to secure legacy web software. Our preliminary experiments with the JForum web application suggest that character-level taint tracking adds 0-15% runtime overhead.
Cognitive Operations, and Non-Conscious Processing in Dreams and Waking Verbal Reports

From findings based on empirical data and a specifically developed qualitative methodology, it is suggested that numbers presented in dream and waking verbal reports are processed cognitively as co...
Adaptive organizations and emergent forms

Over time organizations change and coordinate personnel in new ways as the environment, technologies, and legislation changes. This adaptation is constrained and not all forms of coordination are feasible. Since organizations are inherently computational entities insight is gained by examining adaptation in organizations of intelligent artificial agents. Using ORGAHEAD a series of virtual experiments were run. Results suggest that concurrent learning mechanisms generate the ability to learn meta-change strategies which can be either adaptive or maladaptive. Consequently both organizational performance and form depend on environmental change, agent and structural learning, and the emergence of institutionalized strategies.
NIAID-sponsored 2010 guidelines for managing food allergy: applications in the pediatric population

Data from many studies have suggested a rise in the prevalence of food allergies during the past 10 to 20 years. Currently, no curative treatments for food allergy exist, and there are no effective means of preventing the disease. Management of food allergy involves strict avoidance of the allergen in the patient's diet and treatment of symptoms as they arise. Because diagnosis and management of the disease can vary between clinical practice settings, the National Institute of Allergy and Infectious Diseases (NIAID) sponsored development of clinical guidelines for the diagnosis and management of food allergy. The guidelines establish consensus and consistency in definitions, diagnostic criteria, and management practices. They also provide concise recommendations on how to diagnose and manage food allergy and treat acute food allergy reactions. The original guidelines encompass practices relevant to patients of all ages, but food allergy presents unique and specific concerns for infants, children, and teenagers. To focus on those concerns, we describe here the guidelines most pertinent to the pediatric population.
Pitfalls inherent in retrospective time‐to‐event studies: the example of time to pregnancy

Retrospective studies of time from initiation of risk (for example, transfusion of HIV-infected blood) to the occurrence of an endpoint of interest are useful in epidemiology. One example is studies of time to pregnancy, which have evaluated exposures that may affect human fertility. One can reconstruct the non-contracepting interval required for each woman's most recent pregnancy and then treat the data as if the couples had been studied prospectively. As we illustrate, however, failure-time models can be dangerously misleading when there have been trends over calendar time in exposures under study. We propose an ad hoc method for evaluating possible effects on fertility despite this bias, by making use of external data on trends in the exposure over time. This approach applies a prospective model and generates an empirical p-value, based on comparing the data-based estimated exposure coefficient with its null distribution estimated by simulation. A second method maximizes a conditional likelihood, and we show that this is equivalent to logistically modelling the relative odds for the subject's exposure as related to the reported time she required to achieve pregnancy.