cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluating the impact of space activities in low earth orbit

Abstract The evolution of cataloged orbital debris in low Earth orbit (LEO) over the last quarter of century was analyzed in detail, to gather insights on the development of space activities, on the effectiveness of the debris mitigation measures recommended in the meantime, and on the environmental impact of fragmentations, in particular collisions, both intentional and accidental. The main conclusion was that the observed evolution matched on the whole the predictions of the unmitigated business-as-usual scenarios simulated twenty years ago, and that the benefits caused by the progressive worldwide adoption of mitigation measures were unfortunately offset by a couple of catastrophic collisions and prolonged weak solar activity. Concerning the recorded growth of cataloged fragmentation debris, nowhere have the signs of an exponential increase been revealed so far. Nevertheless, the overall picture has worsened during the last quarter of a century and extreme care is required in planning and conducting new space activities from now on, especially in a phase of increased and ever more rapid exploitation. In order to assess the sustainability of space activities, especially over the next 10–30 years, several environmental criticality indexes have been introduced and discussed, estimating their current values in LEO, as well as their magnitudes associated with specific scenarios of debris growth. They could provide simple tools for evaluating the relative and absolute impact on the debris environment, either in LEO as a whole or in specific altitude shells, of new spacecraft deployments and operations, as in the case of mega-constellations of satellites. The main result of this preliminary analysis was that all indexes were consistent in indicating that from one third to one half of the LEO capacity to sustain long-term space activities – as they are currently conceived – has already been saturated. The 2020s, with their many planned launches, will therefore be crucial years for enforcing more effective debris mitigation and remediation measures.
Machine learning method for light field refocusing.

Light field imaging introduced the capability to refocus an image after capturing. Currently there are two popular methods for refocusing, shift-and-sum and Fourier slice methods. Neither of these two methods can refocus the light field in real-time without any pre-processing. In this paper we introduce a machine learning based refocusing technique that is capable of extracting 16 refocused images with refocusing parameters of \alpha=0.125,0.250,0.375,...,2.0 in real-time. We have trained our network, which is called RefNet, in two experiments. Once using the Fourier slice method as the training -- i.e., "ground truth" -- data and another using the shift-and-sum method as the training data. We showed that in both cases, not only is the RefNet method at least 134x faster than previous approaches, but also the color prediction of RefNet is superior to both Fourier slice and shift-and-sum methods while having similar depth of field and focus distance performance.
Sustaining Patient Portal Continuous Use Intention and Enhancing Deep Structure Usage: Cognitive Dissonance Effects of Health Professional Encouragement and Security Concerns.

Sustaining patient portal use is a major problem for many healthcare organizations and providers. If this problem can be successfully addressed, it could have a positive impact on various stakeholders. Through the lens of cognitive dissonance theory, this study investigates the role of health professional encouragement as well as patients’ security concerns in influencing continuous use intention and deep structure usage among users of a patient portal. The analysis of data collected from 177 patients at a major medical center in the Midwestern region of the United States shows that health professional encouragement helps increase the continuous use intention and deep structure usage of the patient portal, while security concerns impede them. Interestingly, health professional encouragement not only has a direct positive influence on continuous use intention and deep structure usage but also lowers the negative impact of security concerns on them. The research model explains a substantial variance in continuous use intention (i.e., 40%) and deep structure usage (i.e., 32%). The paper provides theoretical implications as well as practical implications to healthcare managers and providers to improve patient portal deep structure usage and sustained use for user retention.
Processing and Characterization of Polycrystalline β″-Alumina Ceramic Electrolytes

In this paper recent developments in the processing and characterization of polycrystalline β″-alumina ceramic electrolytes will be discussed, β″-alumina ceramics have potential uses in diverse devices such as the electrolyte or sodium-ion separator in (1) the sodium-sulfur energy storage battery 1 designed for either electric utility load leveling or automotive propulsion, (2) a high temperature sodium heat engine or thermoelectric device.2 (3) a high electrowinning of sodium metal from molten sodium salts, (4) the purification of sodium metal and (5) various electrochemical devices for measuring sodium and perhaps even oxygen activities.
Time-resolved optical investigation of spatially indirect excitons in GaAs/GaSb quantum dots

Summary form only given. Self-organized quantum dots formed under Stranski-Krastanav growth has been an active area of quantum structure research. Traditional quantum dots grown with III-V materials usually have a normal band lineup, where the electron and hole are confined within the dot, and spatially direct excitons are observed in these structures. Highly strained material systems such as GaSb/GaAs exhibit a staggered band lineup, where electrons and holes are spatially separated. In this paper, we report on the time-resolved optics characterizations of spatially indirect excitons in GaSb-GaAs quantum dots.
The Complexity of Satisfiability of Small Depth Circuits

Say that an algorithm solving a Boolean satisfiability problem x on n variables is improved if it takes time poly(|x|)2 cn for some constant c < 1, i.e., if it is exponentially better than a brute force search. We show an improved randomized algorithm for the satisfiability problem for circuits of constant depth d and a linear number of gates cn: for each d and c, the running time is 2(1 ? ?)n where the improvement $\delta\geq 1/O(c^{2^{d-2}-1}\lg^{3\cdot 2^{d-2}-2}c)$, and the constant in the big-Oh depends only on d. The algorithm can be adjusted for use with Grover's algorithm to achieve a run time of $2^{\frac{1-\delta}{2}n}$ on a quantum computer.
Good News and Bad News about Firm‐Level Stock Returns of Internationally Exposed Firms

We examine stock returns of firms with international exposure. Our empirical work relies on Campbell's variance decomposition framework. Not surprisingly, we find that the volatility of discount rate and cash flow news increase with the degree of international exposure. As firms globalize, the cash flow effect is good news, while the discount rate effect amounts to bad news. The surprising result is that the covariance between the news terms increases with international exposure. This finding provides indirect evidence for the proposition that foreign exchange (FX) risk is a priced factor in the cross-section of risk-adjusted expected returns. JEL Classifications: G12, G15; EFM Classification Code: 330
Enhancement and deterioration of the output characteristics of compressively strained InGaAsP lasers with hydrostatic pressure

Summary form only given. In this work we report on the effect of carrier overflow on the threshold current and slope efficiency of 1.3-/spl mu/m compressively strained InGaAsP MQW lasers. Carrier leakage was enhanced through band structure changes induced by hydrostatic pressure. Hydrostatic pressure increases the direct band-gap energy in semiconductor materials, at rates that are dependent on the elastic properties of the materials.
The GH/IGF-1 system in critical illness.

The Growth Hormone and Insulin-like Growth Factor-1 (IGF-1) axis plays a pivotal role in critical illness, with a derangement leading to profound changes in metabolism. Protein wasting with skeletal muscle loss, delayed wound healing, and impaired recovery of organ systems are some of the most feared consequences. The use of human recombinant Growth Hormone (rhGH) and Insulin-like Growth Factor-1 (IGF-1) – alone and in combination – has been studied extensively in preclinical and clinical trials. This article reviews the current knowlegde and clinical practice of the use of rhGh and IGF-1 in critically ill patients, with a special focus on the trauma and burns patient population.
Mask-programmable multiple-valued logic gate using resonant tunnelling diodes

The design of a 1-input and a 2-input 4-valued logic gate is described. These gates can be used to implement cells of a gate array, with the benefit of having programmable functionality and multiple-valued logic input and output lines. Programmable functionality allows any of the four billion functions of a 2-input 4-valued logic gate to be implemented by the same cell, and multiple-valued logic signal lines can reduce the area needed to be reserved for intercell routing. A key component of these cells is the resonant tunnelling diode, an ultrafast and small quantum electronic device that can be used in conjunction HBTs to make compact literal circuits and decoders. So far as non-gate-array implementations are concerned, compactness can be improved further by a simple algorithm, also presented by the authors, to discard redundancies in the gate structure.
Biopsy criteria for determining appropriateness for active surveillance in the modern era.

Objective To evaluate algorithms to predict insignificant prostate cancer at radical prostatectomy (RP). Methods Five hundred and fifty men (410 Caucasian, 100 African American [AA], and 40 others) with prostate-specific antigen (PSA) level 3 , organ confined, and Gleason score ≤6) cancer at RP. Cancers incorrectly predicted to be insignificant were ranked into 4 groups of increasing aggressiveness. Results Original (Gleason score ≤6, PSA density ≤0.15, ≤2 positive cores, and maximum core involvement ≤50%) and modified Epstein criteria (Gleason score ≤6, PSA density ≤0.15, ≤2 positive cores, and unilateral cancer) had the highest negative predictive values—correct classification of insignificant cancer. Among cancers predicted to be insignificant in Caucasians, 29.9% cases using the original and 27% cases using the modified Epstein criteria had significant cancer at RP. However, more adverse findings at RP were misclassified as insignificant in only 3.5% and 2.2% of cases using the original and modified Epstein criteria, respectively. Of cancers predicted insignificant in AA men, 54.1% cases using the original and 51.6% cases using the modified Epstein criteria were misclassified as insignificant. Dominant anterior tumors were seen in 117 Caucasian (28.5%) and 44 AA men (44%). Conclusion The Epstein criteria maintain their accuracy in the modern era with extended biopsy sampling. The negative predictive values are lower in AA men, in part due to higher frequency of anterior tumors, where multiparametric magnetic resonance imaging should be recommended in AAs considering surveillance.
Behavioral Momentum During a Continuous Reading Task: An Exploratory Study

Adolescents with emotional and behavioral disorders (EBD) often fail to master literacy skills, in part because disruptive behaviors interfere with task engagement and persistence. The theory of behavioral momentum explains the persistence of behavior in the face of changing environmental conditions. The current exploratory study examined variables related to behavioral momentum in the context of a continuous reading task. Participants were three adolescents identified with EBD who were instructional on fifth-grade material. Results indicated that when participants read a third-grade paragraph immediately before a fifth-grade paragraph, they decreased the latency to initiate reading of the fifth-grade paragraph and increased words read correctly per minute on the first 10 words of the fifth-grade paragraph. Results are discussed in terms of the theory of behavioral momentum and the nature of interventions that may be developed to increase reading persistence.
RIBAVIRIN THERAPY IN CRITICALLY ILL CHILDREN

There was a remarkable incidence of respiratory syncytil virus (RSV) in the 1985-86 winter season. The aerosolized antiviral ribavirin was used in 22 patients with suspected or proven RSV disease. Patients were enrolled if they had disease compatible with RSV and evidence of RSV by culture or antigen detection (RSV-Ag). All patients were seriously ill at initiation of therapy, with 82% requiring intensive care and 64% on assisted ventilation (vent.). Underlying medical conditions included prematurity (30%), immunocompromise (23%), pulmonary or cardiac disease (45%), and bacterial infection (9%). Mean duration of ribavirin therapy was 18 hours daily for 6 d. Therapy was discontinued according to clinical improvement, as well as negative RSV cultures and/or RSV-Ag. Twenty of the 22 patients had confirmatory evidence of RSV. Mean time required for diagnosis by RSV-Ag was 0.5 d. vs. 12 d. by culture. Compared with culture, sensitivity of RSV-Ag was 82% and specificity 96% when not receiving antiviral therapy. Premature infants and those with immunodeficiency or infections responded clinically within 2-3 d. of therapy (mean=2 d. on vent.), whereas those with cardiac or pulmonary disease had a delay in clinical improvement until 5-7 d. after initiation of therapy (mean=5 d. on vent.). There were no deaths or serious complications even in pts. receiving assisted vent, during a portion of ribavirin therapy. In this non-controlled study, specific antiviral therapy was rapidly instituted in a group of high risk patients with clinical and laboratory evidence of improvement.
Compliance with fixed-itinerary systems in water-based parks.

A number of studies at land-based parks have indicated that trip information from permit itineraries does not always coincide with actual user behavior. To assess the effectiveness of the fixed-itinerary system at a water-based park, this study examined discrepancies between the itineraries recorded on permits and those reported by overnight users following their visits to Everglades National Park; it also assessed day visitors' reported use of backcountry campsites. Motorboaters were more likely to comply with their permit itinerary than canoeists (76% and 66% compliance rate, respectively). More than one-fourth of day users reported stopping at a backcountry campsite. Respondents reported that sharing campsites with noncomplying campers affected their backcountry experience in either a positive (3%), negative (11%), or neutral (9%) manner.
Continuous pavement profiling with ground-penetrating radar

Ultra-wideband (UWB) monostatic ground-penetrating radar (GPR) has been proven to be very useful in road and highway pavement profiling. Pavement profiling involves estimating the thickness and permittivity of each underground layer, which can be done through layer stripping inversion, using efficient time-delay-estimation algorithms. In monostatic GPR applications, time-delay estimation is routinely performed on a scan-by-scan basis. The authors first propose a multi-scan data model for the continuous survey, by taking into account the vertical motion of moving vehicles as well as the lateral continuity of echoes arising from a multilayered media along the scan direction. Then a new algorithm, referred to as MCPEG (motion compensation and parameter estimation for GPR), is presented for simultaneous motion compensation and time-delay estimation. MCPEG outperforms the conventional scan-by-scan estimation approach in terms of both computational efficiency and estimation accuracy. Numerical and experimental examples are provided to demonstrate the performance of the new algorithm.
Determination of the alkaline earths in glass

Abstract The alkaline-earth group was isolated, after removal of silica, by precipitation as sulfates from an alcoholic solution. Those sulfates were reduced and dissolved by treatment with hydriodic acid. The alkaline earths were separated from each other by ion-exchange chromatography. The results are in good agreement with the values reported by the National Bureau of Standards.
Thinking about Quoins: Strategic Traceability of Architecturally Significant Requirements

Architectural degradation is a common problem in most nontrivial, long-lived software systems. By identifying architecturally significant requirements and establishing trace links from those requirements, via architectural decisions, to code, we can keep developers informed of underlying architectural decisions and help preserve code quality during change maintenance. The Web extra at http://youtu.be/U6MAlOvJpQY is an audio podcast of author Jane Cleland-Huang reading her Requirements column, in which she discusses how requirements engineers can keep developers informed of underlying architectural decisions and help preserve code quality during change maintenance.
The required written history and physical is alive, but not entirely well, in internal medicine clerkships.

Background: Effective written communication is a core competency for medical students, but it is unclear whether or how this skill is evaluated in clinical clerkships. Purpose: This study identifies current requirements and practices regarding required written work during internal medicine clerkships. Methods: In 2010, Clerkship Directors of Internal Medicine (CDIM) surveyed its institutional members; one section asked questions about students’ written work. Results were compared to similar, unpublished CDIM 2001 survey questions. Results: Requirements for student-written work were nearly universal (96% in 2001 and 100% in 2010). Only 23% used structured evaluation forms and 16% reported written work was weighted as a percentage of the final grade, although 72% of respondents reported that written work was “factored” into global ratings. Conclusions: Despite near universal requirements for student written work, structured evaluation was not commonly performed, raising concern about the validity of factori...
Student authority: Antidote to alienation

The widespread disaffection of students from school is manifested in academic failure, indifference, and defiance. These problems can be alleviated, I argue, when an authority structure is developed that combines three components — freedom, power, and legitimacy. Authority understood as either power or freedom is apt to subvert students’ school attachment even while attempting to strengthen it; authority that combines power and freedom, when perceived by all parties as serving a legitimate mission, is apt to enhance engagement. The bonding potency of authority is augmented when it is joined to strongly marked school purposes and dispersed to students. The three components of authority are interwoven with school visions and student authority into various patterns: some schools lean more towards power, others more towards freedom; some operate under highly moralized and totalizing visions, others under vaguer, less moral, and less encompassing visions. The nature and interdependence of the three components ...
Lead acetate-induced contraction in rabbit mesenteric artery: Interaction with calcium and protein kinase C

Abstract Animal studies have demonstrated that low-level lead exposure produces hypertension and that lead can cause contraction of vascular smooth muscle directly. The physiological effects of lead have been associated with both stimulation and inhibition of protein kinase C (PKC). Given that vascular smooth muscle contractility is generally enhanced when protein kinase C is activated, we have tested the hypothesis that lead contracts vascular smooth muscle via stimulation of PKC. Helically-cut strips of rabbit mesenteric artery were mounted in muscle baths for measurement of isometric force development. Cumulative addition of lead acetate (10−10–10−3 M) to the muscle bath produced contractions (concentration necessary to produce half-maximal response −log EC50 = 5.16 ± 0.07). Maximal contraction to lead acetate in arteries denuded of endothelium did not differ from those in intact vessels, supporting the hypothesis that lead-induced contraction is an endothelium-independent event. Contractions to lead acetate were potentiated by the PKC activators, phorbol 12-myristate 13-acetate (TPA; 3 × 10−7 M) and mezerein (3 × 10−7 M), as indicated by leftward shifts in the concentration-response curve and increase in the potency of lead (−log EC50 with TPA: 6.94 ± 0.07; −log EC50 with mezerein: 6.07 ± 0.04). H-7 (6 × 10−6 M), an inhibitor of PKC, decreased maximal contraction to lead ~65% and slightly, but insignificantly, decreased the potency of lead (−log EC50 = 4.82 ± 0.1). The inactive phorbol ester, phorbol 12-myristate 13-acetate 4-0-methyl ether (1 × 10−6 M), did not alter contractile responses to lead (−log EC50 = 4.92 ± 0.09). Vascular contraction to lead partially depends on extracellular calcium as the L-type voltage-gated calcium channel antagonist, verapamil (3 × 10−6 M), decreased leadinduced contractions by 50%. These data indicate that lead interacts with PKC in an endothelium-independent, calcium-dependent manner to cause vascular smooth muscle contraction and suggest that lead-induced increases in vascular contractility may play a role in lead-induced hypertension.
Linking Brain Imaging and Genomics in the Study of Alzheimer's Disease and Aging

My colleagues and I have been using positron emission tomography (PET) and magnetic resonance imaging (MRI) to detect and track the brain changes associated with Alzheimer's disease (AD) and normal brain aging in cognitively normal persons with two copies, one copy, and no copies of the apolipoprotein E (APOE) epsilon4 allele, a common AD susceptibility gene. In this review article, I consider how brain imaging techniques could be used to evaluate putative AD prevention therapies in cognitively normal APOE epsilon4 carriers and putative age-modifying therapies in cognitively normal APOE epsilon4 noncarriers, how they could help investigate the individual and aggregate effects of putative AD risk modifiers, and how they could help guide the investigation of a molecular mechanism associated with AD vulnerability and normal neurological aging. I suggest how high-resolution genome-wide genetic and transcriptomic studies could further help in the scientific understanding of AD, aging, and other common and genetically complex phenotypes, such as variation in normal human memory performance, and in the discovery and evaluation of promising treatments for these phenotypes. Finally, I illustrate the push-pull relationship between brain imaging, genomics research, and other neuroscientific research in the study of AD and aging.
Tailgut cyst in a child

Tailgut cyst, or retrorectal cystic hamartoma, is a rare congenital lesion found in the presacral space. The lesion has been infrequently reported in the literature. We report the MRI findings of a tailgut cyst in a 2-year-old girl who presented with a sacral dimple and skin discoloration.
The2 E↔4 A 2 transition in tetragonal Cr3+ complexes

The2E↔4A2 absorption and emission spectra of [Cr(NH3)5(NO3)](NO3)2, [Cr(NH3)5(NO2)] ·(NO3)2, and [Cr(NH3)5(H2O)](NO3)3 microcrystals have been recorded at 77°K. Tetragonal2E splittings are 209, 188 and 87 cm−1, respectively. An analysis of the limited vibronic structure has been made and compared to the results for the parent “octahedral” complex, [Cr(NH3)6](NO3)3. Vibrations of approximately 270 and 700 cm−1 are prominent.
On the relevance of the strict avalanche criterion

Some recent work concerning the strict avalanche criterion for a Boolean function has been motivated by the claim that a certain cryptographically useful property will be true of any function satisfying the criterion. In the letter it is observed that not only is this claim untrue, but that possession of the property in question is in fact precluded by satisfaction of the strict avalanche criterion.
Response to various shock loadings of the constant recycle‐sludge‐concentration activated‐sludge process

The stability of the model of a completely mixed activated-sludge process holding the recycle sludge concentration, XR, as a system constant subjected to pH, temperature, potassium cyanide, and phenol shock loading was investigated. Soft-drink bottling wastewater was used and maintained at 1000 mg/liter chemical oxygen demand (COD). The hydraulic ratio and recycle sludge concentration were maintained at 0.3 and 7000 mg/liter, respectively. An initial dilution rate of ¼ hr−1 was maintained for pH and temperature shock loading, with ¼ and ⅛ hr−1 for KCN shock loading and ¼, ⅛, and hr−1 for phenol shock loading. It was found that the present system could handle pH shock loading as low as 4.0 and as high as 10.4 without any serious disruption of biological solid concentration and filtrate COD. At pH 4.0 shock loading, filamentous organisms were predominant. Temperature shock loading could be handled from 23 to 36°C without any leakage of effluent filtrate COD. At 46°C temperature shock, a 14 hr period was required to recuperate to the new steady state and provided only 85% of COD removal efficiency. For KCN (50 mg/liger) and phenol (85 mg/liter) shock loading, the dilution rates should be lower than hr−1 in order to shorten the transient period and improve the effluent quality. Biological kinetic constants included cell yield value, maximum growth rate, and the saturation constant, which was varied with the qualitative shock applied.
Data extraction from geometric models for process planning for parallel machines

Abstract Process planning bridges the gap between design and manufacturing. In computer-aided process planning (CAPP) systems, the goal is to automatically extract data from a design model and use it for generating plans for manufacturing. The extracted data should correspond to the type of machining process under consideration, and the extraction techniques must work with the computer-aided design (CAD) model representation. We consider manufacturing information/data extraction from geometric models for parallel machines, particularly mill/turn machines. These are a new class of powerful numerically controlled machine tools with parallel machining capabilities, including turning and milling operations. In this paper, we outline methods for (1) computing the machining axis for a part and (2) determining turning volumes for machining. Examples are included for both methods.
Discharge characteristics of a simulated solar cell array

Measurements of the transient characteristics associated with the discharge of a simulated solar array are presented. A capacitively coupled probe is used to measure the discharge current, and antennas are used to measure the electromagnetic radiation. Discharges were observed at low surface voltages and several modes of discharge were observed. The maximum discharge current is found to be 0.2 A. This value is several orders of magnitude higher than that reported by previous measurements. Experimental evidence suggests that the inverted voltage gradient is a very likely triggering mechanism for solar array discharges.
"Pediatrics perspectives" on a new year and a new congress.

* Abbreviations: AAP — : American Academy of Pediatrics The start of a new year heralds 2 noteworthy events in our nation’s history, one of which may be more familiar to you than the other. The first is the convening of what will be the 113th US Congress and the second, perhaps less known to many, is the 65th anniversary of our journal, Pediatrics . Why announce these events together? Because the uniting force that brings our journal and our nation’s legislative body together this year is the same one that has united us in the past, along with the American Academy of Pediatrics (AAP) and all other pediatric advocacy groups and publications: the future of children, in this country and around the world. You do not need to be a congressional leader to know that this past election year was fraught with turbulence in campaigns waged locally, statewide, and nationally, and with that turbulence, an agenda for children was not always front and center. A new year, however, brings new hopes and expectations, and to highlight those expectations, we are publishing a special article this month by Block et al1 that represents the policy agendas of 5 leading national pediatric organizations in regard to what Congress should be focusing on to improve care and outcomes for children. The good news in this article is that each organization’s wish list could result … Address correspondence to Lewis R. First, MD, MS, Editor-in-Chief, Pediatrics Editorial Office, University of Vermont College of Medicine, 89 Beaumont Ave, Given Courtyard S250, Burlington, VT 05405. E-mail: lewis.first{at}uvm.edu
Investigating the plasmonics of a dipole-excited silver nanoshell: Mie theory versus finite element method

This report compares COMSOL's finite element method (FEM) algorithm with the Mie theory for solving the electromagnetic fields in the vicinity of a silica-silver core-shell nanoparticle when excited by a radiating dipole. The novelty of this investigation lies in the excitation source of the nanoshell system: an oscillating electric dipole is frequently used as a model for both molecular scattering and molecular fluorescence; moreover, a common classical model of atomic or molecular spontaneous emission is a decaying electric dipole. The radiated power spectra were evaluated both analytically and numerically by integrating the Poynting vector around 20, 60 and 100 nm nanoshells, thereby solving the total and scattered fields generated by a dipole positioned inside the core and in the surrounding air medium, respectively. The agreement was excellent in amplitude, plasmon resonance peak position and full width at half-maximum. The FEM algorithm also generates accurate solutions of the near-field electromagnetics in the spatial domain, where the E-field behavior as a function of polar angle theta for a fixed observation radius was evaluated. The quasistatic approximation, which is valid for small nanoparticles, is also employed to assess its limitations relative to the Mie and FEM algorithms.
Equilibrium temperatures, pressures, and oxygen fugacities of the equilibrated chondrites

Abstract Olivine-pyroxene pairs from the equilibrated chondrites (types 5 and 6) record the following physical conditions: T = 880° ± 150°C and P = 5 ± 5 kilobars. The oxygen fugacity at 880°C is 10−17.5 ±1.2. These oxygen fugacities plot on the graphite surface at 1 atmosphere total pressure.
Clinical ultility of intravascular ultrasound and 3D reconstruction of images

Intraluminal vascular ultrasound (IVUS) is developing rapidly as a method to define the transmural anatomy of vascular structures for both diagnostic and therapeutic applications. Current devices use various configurations of transducers at the end of an intraluminal catheter to make real time images of cardiac structures and vessel walls. These devices may have diagnostic applications, particularly at the time of angiography or catherization for symptomatic cardiovascular disease.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Attack behavior in a multiple fixed-ratio schedule of reinforcement

Two pigeons were trained on a multiple, fixed-ratio schedule of reinforcement. When the key was red, a fixed-ratio 25 was in effect; when it was blue, a fixed-ratio 100 was in effect. Both pigeons consistently attacked a nearby stuffed pigeon only when the key color was blue even though such attack was not explicitly reinforced.
Lipopolysaccharide-induced changes in rat gastric H/K-ATPase expression.

Objective:To evaluate lipopolysaccharide (LPS)-induced inhibition of gastric acid secretion.Summary Background Data:Endotoxemia from LPS inhibits gastric acid secretion by an unknown mechanism. Bacterial overgrowth in the stomach caused by decreased acid secretion could be responsible for nosocomial
Resveratrol, a natural phenolic compound, inhibits cell proliferation and prevents oxidative DNA damage.

Abstract Resveratrol (3,4′,5-trihydroxystilbene) is a naturally occurring phenolic compound which is present at high levels in wine and has been recently proposed as a potential cancer chemopreventive and chemoterapeutic agent. In this study, we evaluated the antiproliferative activity of resveratrol on a panel of cell lines of various histogenetic origin, including normal rat fibroblasts and mouse mammary epithelial cells compared to human breast, colon and prostate cancer cells. The concentration of resveratrol inhibiting cell growth by 50% (IC50) ranged from about 20 to 100 μM. At such concentration, we were unable to detect a significant increase in the apoptotic index in most of the cell lines analyzed. We also studied the effects of resveratrol on cell cycle distribution. The most striking effect was a reduction in the percentage of cells in the G2/M phase which was most frequently associated with an increase of cells in the S phase of the cell cycle. We also found that resveratrol is able to prevent the increase in reactive oxygen species (ROS) following exposure to oxidative agents (i.e. tobacco-smoke condensate (TAR) and H2O2). Resveratrol also reduced nuclear DNA fragmentation, as assessed by single cell gel electrophoresis (comet test). Taken together our results suggest that resveratrol can act as an antimutagenic/anticarcinogenic agent by preventing oxidative DNA damage which plays a pivotal role in the carcinogenic activity of many genotoxic agents.
Combating web plagiarism and improving internet safety by authenticating web content

Web content plays an important role in the contemporary information economy. Even though web content is used to generate advertising revenues for authors, and serves as an important reference and knowledge discovery resource for readers, proving original authorship and preventing plagiarism are not easy on the Internet. This paper presents the design and analysis of an automatic cryptography based solution for detecting and correcting web plagiarism. Unforgeable cryptographic commitments for originally authored content are stored in a distributed hash table over-layed on enhanced web browsers. Since it is based on content authentication, this solution not only protects against web plagiarism, but also improves web safety by preventing phishing attacks based on web page copying, poisoned DNS caches, or hacked web sites.
Dynamic Changes in LHRH Neurovascular Terminals with Various Endocrine Conditions in Adults

Luteinizing hormone-releasing hormone (LHRH) release is required for ovulation in mammals. Although evidence for the direct action of gonadal steroids on LHRH neurons has been minimal, their importance in inducing the preovulatory surge of LHRH is unequivocal. We have identified a subgroup of LHRH neurons with progestin receptors in guinea pigs. Given their central position, these neurons may constitute foci of initial activity, which are amplified throughout the population of LHRH neurons, resulting in increased LHRH neurosecretion on the afternoon of proestrus. Additionally, gonadal steroids may regulate LHRH secretion at the level of the terminals. Using immunoelectron microscopy and image analysis, we have illustrated the dramatic influence of gonadal steroids on individual LHRH terminals in the median eminence of rats. Indirectly, gonadal steroids may modulate LHRH release by modulating glial elements. Using double-label fluorescence confocal microscopy, we illustrate that LHRH terminals in the median eminence are encased by end-feet of tanycytes. Acting on glial elements, gonadal steroids may regulate access of LHRH terminals to the basal lamina and influence the amount of the neuropeptide reaching the portal vessels. We propose that during the preovulatory surge, LHRH release is coordinated by synergistic mechanisms operating at the level of particular subgroups of neuronal perikarya and/or discrete regions of the median eminence. These synergistic actions may ensure that LHRH is released in a precipitous fashion, to induce the surge of LH from the pituitary, required for ovulation.
Signal quality assessment of retinal optical coherence tomography images.

Purpose The purpose of this article was to assess signal quality of retinal optical coherence tomography (OCT) images from multiple devices using subjective and quantitative measurements. Methods A total of 120 multiframe OCT images from 4 spectral domain OCT devices (Cirrus, RTVue, Spectralis, and 3D OCT-1000) were evaluated subjectively by trained graders, and measured quantitatively using a derived parameter, maximum tissue contrast index (mTCI). An intensity histogram decomposition model was proposed to separate the foreground and background information of OCT images and to calculate the mTCI. The mTCI results were compared with the manufacturer signal index (MSI) provided by the respective devices, and to the subjective grading scores (SGS). Results Statistically significant correlations were observed between the paired methods (i.e., SGS and MSI, SGS and mTCI, and mTCI and MSI). Fisher's Z transformation indicated the Pearson correlation coefficient ρ ≥ 0.8 for all devices. Using the Deming regression, correlation parameters between the paired methods were established. This allowed conversion from the proprietary MSI values to SGS and mTCI that are universally applied to each device. Conclusions The study suggests signal quality of retinal OCT images can be evaluated subjectively and objectively, independent of the devices. Together with the proposed histogram decomposition model, mTCI may be used as a standardization metric for OCT signal quality that would affect measurements.
Urine Electrolyte Composition and Diuretic Therapy in Heart Failure Back to the Future

In the now classic 1985 fantasy-comedy film Back to the Future , teenager Marty McFly travels back in time 30 years in a DeLorean sports car/modified time machine and fortuitously befriends the younger version of his father. Marty finds his father to be a meek high school teenager and realizes that Biff Tannen, the bullying supervisor of the future version of his father, was also his father’s bully in high school. What was true then is true now. Article see p 766 In this issue of Circulation: Heart Failure , Verbrugge et al1 bring an old concept back to the present by proposing the use of urine sodium (Na+) and chloride (Cl−) concentrations in guiding diuretic therapy for the treatment of heart failure. In this prospective cohort study, the investigators recruited patients with heart failure and worsening congestive symptoms, evidence of left ventricular ejection fraction <45% by echocardiogram, or clinical signs of volume overload. Study subjects were observed in an intensive care unit setting and placed on a low NaCl diet (<3 g per day) with restricted fluid intake (1.5 L). They received a bolus of intravenous bumetanide in 3 consecutive 24-hour intervals, typically in combination with spironolactone±vasodilators and their usual medications for heart failure, including β-adrenergic antagonists and renin–angiotensin system blockers. In some cases, chlorthalidone and acetazolamide were added. Echocardiograms were performed at baseline and after the 3-day period. Urine was collected for 3 consecutive 24-hour intervals. Baseline …
Effects of structural disorder and surface chemistry on electric conductivity and capacitance of porous carbon electrodes

This article reports on changes in electric double layer charge storage capacity as a function of surface chemistry and graphitic structure of porous carbon electrodes. By subjecting 20 nm to 2.0 μm sized carbide-derived carbons (CDCs) synthesized at 800 °C to high-temperature vacuum annealing at 700–1800 °C, we produce three-dimensional internal surface architectures with similar pore sizes and volumes but divergent surface chemistry and wall graphitization. Annealing increases carbon ordering and selectively removes functional groups, and both transformations affect conductivity and wettability. Contrary to an expected increase in gravimetric capacitance, we demonstrate no increases in charge storage despite increased conductivity and pore accessibility. At the same time, annealing improves the charge/discharge rates in EMIm-TFSI ionic liquid electrolyte. The annealing process eliminates faradaic reactions that limit the voltage window, but potentially accelerates catalytic breakdown of the ions themselves. We therefore corroborate the theory that surface groups and defects in the graphitic structure act as dopants that allow facile movement of ions into pores, improve screening in the superionic state, and affect the quantum capacitance contribution from the carbon structure.
β-Adrenergic Stimulation of Aldosterone Production by Rat Adrenal Capsular Explants*

Adrenal glomerulosa was examined for the presence of an adrenergic influence on aldosterone production. Cultured rat adrenal capsular explants were transferred to a perifusion system where the effect of exposure to catecholamines on aldosterone production was assessed. At 10(-6) M, isoproterenol greater than epinephrine greater than norepinephrine significantly stimulated aldosterone production, whereas at 10(-8) M only isoproterenol showed significant stimulation. Propranolol, a beta-adrenoreceptor antagonist, inhibited stimulation by epinephrine, and the phosphodiesterase inhibitor, 1-methyl-3-isobutylxanthine, enhanced stimulation by a submaximal dose of epinephrine. Epinephrine and norepinephrine were found by radioenzymatic assay to be present in fresh as well as cultured capsular tissue, although levels were considerably lower in tissue that had been in culture (about one tenth that of fresh tissue). The epinephrine-norepinephrine ratio was similar in capsule and medulla, suggesting a medullary source of capsular catecholamines. Whether catecholamines in the capsule arose from the in vitro manipulation of adrenal tissue or existed in vivo is unclear. In summary, beta-agonists stimulate aldosterone production in cultured rat capsular explants.
Oriskany Sandstone Lithofacies, Paleoenvironment, and Fracture Porosity in Somerset County, Pennsylvania: ABSTRACT

The Lower Devonian Oriskany (Ridgeley) Sandstone is an important deep exploration target in the Appalachian basin. In outcrop, the Oriskany is typically a calcareous quartzarenite with few discernible lithologic variations. Petrographic examination of two drill cores of the Oriskany-Needmore Shale interval from south-central Somerset County indicates that identifiable lithofacies of the upper Oriskany Sandstone exist in the subsurface. Oriskany lithofacies are defined as silica-cemented quartzarenite, sandy biosparite, calcareous-cemented quartz wacke, and coquinoid calcareous-cemented quartzarenite. These lithofacies are interpreted as depositional features of a shallow marine sand-bar complex, corresponding to central-bar, bar-margin, interbar, and storm-generated sheet sand (tempestite) depositional units. Paleoenvironmental interpretations are supported by diagnostic trace-fossil assemblages and coarsening-upward grain size trends indicative of vertically stacked marine bars. Correlation of gamma-ray logs from Oriskany wells across Somerset County suggests that these marine bars are laterally discontinuous and may change abruptly in thickness over relatively short distances. The basinal Needmore Shale overlies the Oriskany in this area, indicating a deepening of the depositional setting after Oriskany deposition. Although vertically oriented fractures were observed in all the Oriskany lithofacies and Needmore Shale, most of the fractures are healed by secondary calcite. Fracture porosity occurs primarily in the silica-cemented quartzarenite lithofacies, or central-bar paleoenvironmental unit. The quartzarenite lithofacies is recognizable on gamma-ray logs by its blocky, low API unit signature at the top of sequences that exhibit a downward increase in shale content. As the presence of fracture porosity is important in Oriskany natural gas production in this region, central-bar units are primary targets for exploration. End_of_Article - Last_Page 1930------------
Determination of mass transfer coefficients during freeze drying using modeling and parameter estimation techniques

Abstract An approach using mathematical modeling and parameter estimation techniques was established to determine the best-fit mass transfer coefficients of the dried-layer resistance during primary drying of pharmaceuticals, in order to minimize experimental efforts. For modeling of the primary drying process, the equations associated with heat and mass transfer mechanisms established by Pikal were used as the model equations, whereas the parameter estimation was accomplished by Powell's nonlinear least-squares minimization algorithm. The advantages of this approach include that it can be applied to analyze various types of measurable quantities, such as the cumulative mass of sublimation M t , the temperature profiles at the bottom center of the frozen layer T b , and the pressure profiles of the vials. It can also be used for these quantities measured using the vials with different heat transfer coefficients. To test the performance of the proposed approach, hypothetical values of M t and T b with perturbed errors, were simulated using the modeling algorithm and a random number generator. These values were in turn used as the input data for parameter estimation. The results show that the best-fit mass transfer coefficients are successfully obtained using either the hypothetical M t or T b profiles, with appropriate initial guesses of the parameters. All computations in modeling and parameter estimation were developed in FORTRAN and compiled using Microsoft FORTRAN compiler, of which the source codes and documentation, with detailed mathematical equations and computation steps, are available upon request.
The rat parvocellular reticular formation: I. Afferents from the cerebellar nuclei.

Abstract The present report elucidates the location of the cells of origin of the cerebellar nuclear-parvocellular reticular projection in the rat. Injection of horseradish peroxidase (HRP) into the parvocellular reticular formation resulted in labeled neurons in the dorsolateral protuberance of the contralateral medial nucleus and bilaterally in the dorsolateral hump region and the large celled subgroup of the lateral nucleus. A small number of labeled cells were found in the middle part of the contralateral medial nucleus. The few HRP-positive cells in the interpositus nuclei were adjacent to the dorsolateral hump. No labeled neurons were observed in the caudomedial portion of the medial nucleus or the small-celled region of the lateral nucleus.