cssi/SciSciGPT-SciSciNet huggingface dataset:
A dynamic stall model for analysis of cross-flow turbines using discrete vortex methods

Abstract Cross-flow turbine blades operate in an unsteady environment over large ranges of angle of attack and Reynolds number, often enduring dynamic stall. The hydrodynamics are further complicated because the circular orbit of the blades changes their effective curvature. In order to address these technical challenges with modeling cross-flow turbines, this article presents a novel dynamic stall model with flow curvature correction. The dynamic stall model extends Beddoes-Leishman dynamic stall theory, including several effects such as proper asymptotic behavior at large (∼90°) angles of attack, influence of reduced-pitch rate on the stall angle, dynamics of the flow separation point, and changes in effective camber due to flow curvature. Further, the model enables rapid hydrodynamic analysis of cross-flow turbines using free vortex methods. Important design parameters such as blade thickness and camber are explicitly accounted for in the model, which enables parametric study of turbine configurations and therefore makes the model useful for system-level turbine optimization. Numerical predictions are validated by experimental data for several cases, including ranges of blade profile, toe angle, solidity, and tip speed ratio.
Abstract TMP60: Validation of an Education Gauge for Measuring Stroke Outreach Efforts

Background: To improve rural population access to telestroke sites for referral and treatment, hospitals are required to fulfill monthly educational outreach. Telehealth sites that provide stroke o...
Evidence From the Past: AI Decision Aids to Improve Housing Systems for Homeless Youth.

Could an AI decision aid improve housing systems that assist homeless youth? There are nearly 2 million homeless youth in the United States each year. Coordinated entry systems are being used to provide homeless youth with housing assistance across the nation. Despite these efforts, the number of homeless youth still homeless and unstably housed on the street remains very high. Motivated by this fact, we initiate a first study to create AI decision aids for improving the current housing systems for homeless youth. First, we determine whether the current rubric for prioritizing youth for housing assistance can be used to predict youth's homelessness status after receiving housing assistance. We then consider building better AI decision aids and predictive models using other components of the rubric. We believe there is much potential for effective human-machine collaboration in the context of housing allocation. We plan to work with HUD and local communities to develop such systems in the future.
Rigorous Estimation of Floating-Point Round-Off Errors with Symbolic Taylor Expansions

Rigorous estimation of maximum floating-point round-off errors is an important capability central to many formal verification tools. Unfortunately, available techniques for this task often provide very pessimistic overestimates, causing unnecessary verification failure. We have developed a new approach called Symbolic Taylor Expansions that avoids these problems, and implemented a new tool called FPTaylor embodying this approach. Key to our approach is the use of rigorous global optimization, instead of the more familiar interval arithmetic, affine arithmetic, and/or SMT solvers. FPTaylor emits per-instance analysis certificates in the form of HOL Light proofs that can be machine checked.In this article, we present the basic ideas behind Symbolic Taylor Expansions in detail. We also survey as well as thoroughly evaluate six tool families, namely, Gappa (two tool options studied), Fluctuat, PRECiSA, Real2Float, Rosa, and FPTaylor (two tool options studied) on 24 examples, running on the same machine, and taking care to find the best options for running each of these tools. This study demonstrates that FPTaylor estimates round-off errors within much tighter bounds compared to other tools on a significant number of case studies. We also release FPTaylor along with our benchmarks, thus contributing to future studies and tool development in this area.
Show your work: math curricula, knowledge, and rehumanizing pedagogy

In many countries, in contemporary math curricula, particularly in early childhood and childhood classrooms, it is considered crucial to encourage children to show their work, to concretely represe...
The Complexity of the “x” in Latinx: How Latinx/a/o Students Relate to, Identify With, and Understand the Term Latinx:

The usage of term Latinx has gained popularity in higher education settings. This study documents how 34 Latinx/a/o students relate to, identify with, and understand the term Latinx. Participants p...
Curcumin: a promising therapeutic in Parkinson's disease treatment

Abstract Curcumin, a vital culinary spice, shows substantial antioxidant, antiinflammatory, antiapoptotic, and anticancer effects. Therefore, it has long been used as a therapeutic agent for manifold diseases such as neurodegenerative diseases and cancer. It also acts as a vital metal chelator and reverses metal-mediated neurotoxicity. However, low bioavailability and short systemic circulation limit its success significantly. To overcome these issues, a few curcumin derivatives such as demethoxycurcumin and bisdemethoxycurcumin were used. They showed better bioavailability compared to curcumin. Additionally, a plethora of drug delivery systems were designed using nanotechnology to enhance bioavailability and target brain. This chapter focuses on neuroprotective role of curcumin, its derivatives, and delivery systems preferably in Parkinson's disease treatment.
Anaphylactic shock due to latamoxef sodium in a child

A 9-year-old girl with recurrent urinary tract infection received an IV infusion of latamoxef sodium 1.5 g twice daily. About 2 minutes after the first latamoxef sodium infusion, the girl developed generalized skin flushing and itching, blurred vision, lip cyanosis and chest congestion. Her heart rate was 70 beats/min, blood pressure was 58/27 mmHg and breathing rate was 25/min. Latamoxef sodium was stopped immediately and she was given oxygen inhalation through nasal tube and electrocardiographic monitoring. She was treated with an intravenous bolus of adrenaline 0.3 mg, an intravenous bolus of promethazine hydrochloride 25 mg, an IV infusion of 0.9% sodium chloride injection 500 ml, oral chlorphenamine 8 mg and an IV infusion of methylprednisolone 80 mg. About 1 hour later, her blood pressure was 80-90/41-47 mmHg. Adrenaline 1 μg/(kg·min)via IV pump was given. Two minutes later, her blood pressure increased to 157/78 mmHg and the heart rate was 88 beats/min. Adrenaline was gradually reduced and stopped. Key words: Moxalactam; Anaphylaxis; Child
Successful Long-Term Control of the Syndrome of Episodic Angioedema With Eosinophilia (Gleich Syndrome) With Low-Dose Imatinib Mesylate and Prednisone:

The syndrome of episodic angioedema with eosinophilia, first reported over 40 years ago, is a hypereosinophilic disorder that, uniquely, is not associated with end-organ pathology. However, patients develop a constellation of symptoms that include angioedema, urticaria, fatigue, and fever. Episodes are accompanied by massive hypereosinophilia and weight gain. Type II serum cytokine levels (IL-5, IL-13, IL-9, and IL-10) show cyclic variations peaking at or just prior to the peak of eosinophilia and an abnormal Th2 cell phenotype has been reported. Attacks may occur with predictable regularity and have been described in both adults and children. Glucocorticoid therapy reliably reverses symptoms with accompanying diuresis, defervesce, and normalization of the eosinophil count. In this report, a patient who had the syndrome of episodic angioedema with eosinophilia exceeding 20 years is reported. He has had no end-organ damage to date. Testing for the CHIC2 deletion, a surrogate for the FIP1L1-PDGFRA fusion, was negative. Use of imatinib mesylate, initially as a steroid-sparing agent, and subsequently as a maintenance medication, plus low-dose prednisone has provided long-term control of hypereosinophilia and all clinical manifestations.
4x3 Mueller matrix imager for cervical health diagnosis

Invasive cervical cancer is a slow progressing disease, taking more than 10 years to fully develop from infection. The anatomic accessibility and possible treatment of precancerous lesions make early screening a suitable and effective management. An imager based on Mueller matrix polarimetry consisting of a polarization state generator of four input polarization states and a polarization state analyzer on board of the detector, a polarized camera, is introduced. A 4x3 reduced form of the Mueller matrix is decomposed to extract polarimetric parameters such as the retardance, depolarization and orientation. The use of this device on biological samples is tested.
Plasma Generation by Hypervelocity Impact

Tiny dust particles striking targets at hypervelocity speeds (greater than ~5-10 km/s) will vaporize and ionize both the projectile and part of the target material, forming a plasma that quickly expands into the surrounding environment. Such impacts occur on spacecraft and the resulting plasma has the potential to interact with both the space environment and components aboard the spacecraft. Modeling the formation and expansion of hypervelocity impact-produced plasmas requires the combination of many areas of physics: solid elasticity, plasticity, and fracture; phase change; non-ideal ionization; transition between highly collisional and collisionless regimes, and kinetic plasma dynamics. While many ground-based experiments have been performed using light gas guns and Van de Graaff accelerators, these experiments do not always agree on fundamental properties of these plasmas such as temperature, expansion velocity, and total charge produced. We show a series of combined magnetohydrodynamic (MHD) and hydrocode simulations using the ALEGRA-MHD code that couples to a particle-in-cell (PIC) code. We determine the aforementioned plasma properties as a function of impact speed, materials, and impact angle. When the impact plasma is at high densities, we also show the formation of a diamagnetic cavity near the impact site. These results are compared to semi-analytic models and ground-based experimental results. A clear understanding of the plasma as it is formed and expands will allow further analysis of instabilities, wave excitation and coupling, and ultimately how these plasmas may interfere with spacecraft operations.
Impact of a Multiplex Polymerase Chain Reaction Panel on Duration of Empiric Antibiotic Therapy in Suspected Bacterial Meningitis.

Background Multiplex polymerase chain reaction (PCR) panels allow for rapid detection or exclusion of pathogens causing meningitis and encephalitis (ME). The clinical impact of rapid multiplex PCR ME panel results on the duration of empiric antibiotic therapy is not well characterized. Methods We performed a retrospective prepost study at our institution that evaluated the clinical impact of a multiplex PCR ME panel among adults with suspected bacterial meningitis who received empiric antibiotic therapy and underwent lumbar puncture in the emergency department. The primary outcome was the duration of empiric antibiotic therapy. Results The positive pathogen detection rates were similar between pre- and post-multiplex PCR ME panel periods (17.5%, 24 of 137 vs 20.3%, 14 of 69, respectively). The median duration of empiric antibiotic therapy was significantly reduced in the post-multiplex PCR ME panel period compared with the pre-multiplex PCR ME panel period (34.7 vs 12.3 hours, P = .01). At any point in time, 46% more patients in the post-multiplex PCR ME panel period had empiric antibiotic therapy discontinued or de-escalated compared with the pre-multiplex PCR ME panel period (sex- and immunosuppressant use-adjusted hazard ratio 1.46, P = .01). The median hospital length of stay was shorter in the post-multiplex PCR ME panel period (3 vs 4 days, P = .03). Conclusions The implementation of the multiplex PCR ME panel for bacterial meningitis reduced the duration of empiric antibiotic therapy and possibly hospital length of stay compared with traditional microbiological testing methods.
Provably Robust Model-Centric Explanations for Critical Decision-Making

We recommend using a model-centric, Boolean Satisfiability (SAT) formalism to obtain useful explanations of trained model behavior, different and complementary to what can be gleaned from LIME and SHAP, popular data-centric explanation tools in Artificial Intelligence (AI). We compare and contrast these methods, and show that data-centric methods may yield brittle explanations of limited practical utility. The model-centric framework, however, can offer actionable insights into risks of using AI models in practice. For critical applications of AI, split-second decision making is best informed by robust explanations that are invariant to properties of data, the capability offered by model-centric frameworks.
Pharmacists' perceptions and attitudes toward drug importation into the State of Florida.

BACKGROUND The Department of Health and Human Services and the Food and Drug Administration released the Safe Importation Action Plan in July 2020 detailing methods to import medicines from Canada to combat increasing drug costs. In November 2020, Florida became the first state in the United States to create and propose an importation plan from Canada. This study examines the proposal submitted by Florida, Florida pharmacists' perceptions of the program on patient safety, and Florida pharmacists' thoughts on the pharmacy operational impact. METHODS This was a cross-sectional study utilizing an electronic questionnaire sent to pharmacist members of the Florida Pharmacy Association. The survey incorporated closed-ended and open-ended questions. The results from the study were reported and analyzed through descriptive statistics, qualitative and quantitative data. RESULTS Two-hundred and forty-four pharmacists responded to the survey. Of those respondents, 25% stated they had no knowledge about Florida's drug importation plan. Less than 12% of respondents stated they would trust the safety and quality of imported medicines. Seventy percent of pharmacists expressed concerns regarding the changes required in pharmacy operations to increase medicine safety. About half of the respondents questioned whether this plan would promote cost-savings as intended. CONCLUSION Florida pharmacists believe the drug importation plan does not address all aspects of patient and medicine safety and expressed concerns regarding logistical operations of a pharmacy. This article highlights those concerns and acts as a summons to action.
8 Disqualified Olympians: The Skeptical Greek View of Divine Judges

Greek literature and legal practice exhibit a reluctance, bordering on refusal, to deem the Olympian gods as fit judges, either of themselves or of humans. Although there is an occasional word of praise, the gods are routinely portrayed as preoccupied with advancing their own interests, and notably petulant over perceived slights to themselves. In Aeschylus’ mythical account of the creation of Athens’ first court, Athena declares herself incapable of judging the defendant, a mere mortal, without human jurors to help her. Respectable divine agents of justice are almost always figured as abstractions (“Themis” or the spirits in Hesiod), named, not portrayed with any specificity, devoid of personality — not to speak of judges who have decided a specific case in a specific way.Perhaps reflecting this ambivalence about the quality of divine judging, Athenian courts were conceived of as predominantly mortal affairs. To be sure, traces of divine participation can be seen, for example, in the use of oaths and the process of juror selection. But despite the ubiquity of religious symbols and rituals in Athenian life, Athenian jurors did not, for the most part, seek the assistance of the divine or draw legitimacy from the involvement of the gods in their decisions.This pessimistic view of the gods as judges is not merely a byproduct of anthropomorphism, for the Greeks imagined the gods not merely as flawed humans, but as lacking the seriousness mortals acquired precisely as a consequence of their impending death.
An Ontology of mHealth

Amidst this rapid explosion of interest in mHealth there is absent a clear definition of the concept and its domain. We review the extant definitions of the term and present an ontology of mHealth to articulate its combinatorial complexity. The ontology parsimoniously encapsulates the logic of mHealth. It moves away from technology-based conceptualizations to a systemic one. It can be used to articulate the components and fragments which constitute mHealth using structured natural English sentences and phrases. It serves as a multi-disciplinary lens to study the topic drawing upon concepts from information systems, knowledge management, healthcare policy, and healthcare information technology. The ontology can be used to systematically map the state-of-the-research and the state-of-the-practice in mHealth, discover the gaps in research and between research and practice, and formulate a strategy to bridge the gaps.
Email Advice Part 2

Lawyers use email heavily, and this piece gives advice for using it carefully. Before sending any email in a professional setting, think, pause, think again, then send.
Ansi and IEC Standards for, and Evaluation of, Radiation Detection Instrumentation

During the last quarter of 2002, an effort was started to develop performance requirements for radiation instrumentation used for the detection of illicit trafficking of radioactive material. Coordinated by the US National Institute of Science and Technology (NIST), a team was formed to establish writing committees for the development of these requirements as American National Standards Institute (ANSI) standards. The core of the new area was developed as ANSI N42, Homeland Security Instruments. A series of standards were developed followed by testing and evaluation (T&E) protocols that would be used for specific testing. Four US National Laboratories provided T&E support and work commenced to test instruments provided by manufacturers at no cost. During this time, discussions began regarding the formation of a new work group within the International Electrotechnical Commission (IEC). This new work group would be located within technical committee (TC) 45 which addresses nuclear instrumentation. This new work group, 15B, also began developing international standards to address the same instrument types. Following development of ANSI standards, the testing and evaluation process began, running for two distinct rounds. The results of the work was consolidated by NIST and released back to individual companies as well as the user communitymore » in a controlled manner. This document will provide details regarding the standards and their basis and status, as well as some information regarding the T&E process used in the USA.« less
Numerical simulations for the current collection by a tethered-satellite in the ionosphere

The current collection by a tethered-satellite in the low earth orbit and the processes involved in this ionospheric phenomenon were investigated by numerical simulations. Initially a 2-D case was considered in the cylindrical geometry. The system solved numerically was comprised of a long cylindrical satellite, an arbitrary orientation of the ambient magnetic field, and a Maxwellian plasma flowing relative to the satellite. The relative orientation between the magnetic field and the plasma flow has been found to effect the current collection, with an enhancement achieved when the magnetic field and the plasma flow are perpendicular. Results presented include the plasma distributions, sheath structures, and the current-voltage characteristics. For a typical orbit in the ionosphere, the relative plasma flow is perpendicular to the magnetic field, and this case has been extensively studied. >
Enhanced Seasonal Rainfall in Northern Venezuela and the Extreme Events of December 1999

Abstract Torrential rainfall during December 1999 resulted in devastating floods and landslides along the northern coast of Venezuela. These events occurred in an area with a predominantly dry climate, took place during what is regionally the dry season, and were preceded by unusually heavy seasonal rainfall. An observational study was undertaken in an attempt to identify anomalous features of the climate system associated with both the enhanced seasonal rainfall prior to the landslides as well as the extreme December rainfall events that triggered them. Observational data for the period 1950–99 are used to provide historical context. Results indicate that the copious seasonal rainfall prior to the floods was associated with anomalous conditions in both the tropical Pacific and Atlantic basins similar to past events, although some features were unusually strong in 1999. The extreme daily rainfall in December 1999 was associated with atmospheric circulation features originating in the extratropical Norther...
Fuzzy logic-based downlink subchannel allocation for capacity maximization in OFDMA femtocells

In this paper, we propose a fuzzy logic-based dynamic subchannel allocation scheme for densely deployed femtocell networks affected by strong co-tier interference. The channel model includes Rayleigh fading with path loss and the femtocells use OFDMA-based channel access. The reported signal-to-interference plus noise ratio (SINR) values at femtocell base stations are used to form a fuzzy superset, which in turn is utilized to allocate subchannels in an optimal way. The results are compared with the traditional user-oriented and channel-oriented subchannel allocation schemes. The proposed scheme provides almost the same system capacity with better fairness as compared to traditional channel-oriented scheme, while it also improves the sum-rate capacity of the femtocell network as compared to the user-oriented scheme. Simulations have been performed to judge the quality of proposed algorithm for a variety of densely deployed femtocells.
Wolterstorff on Love and Justice

In Justice in Love, Nicholas Wolterstorff argues for a unique ethical orientation called “care-agapism.” He offers it as an alternative to theories of benevolence-agapism found in Christian ethics on the one hand and to the philosophical orientations of egoism, utilitarianism, and eudaimonism on the other. The purported uniqueness and superiority of his theory lies in its ability to account for the conceptual compatibility of love and justice while also positively incorporating self-love. Yet in attempting to articulate a “bestowed worth” account of human dignity—in which dignity is given by divine love and respected in acts of justice—Wolterstorff leans on an unstable characterization of how love and the good are conceptually interwoven. As a result, his reader cannot be sure about the theoretical superiority of care-agapism. Moreover, Wolterstorff's attempt to value self-love and at the same time reject eudaimonism depends on a dubious interpretation of Augustine carried over from Justice: Rights and Wrongs, which itself further depends on a mischaracterization of the possible varieties of eudaimonism. This mistake is unfortunate because, on a closer reading of Augustine, one finds an agapistic account of eudaimonism that could have significantly helped Wolterstorff's overall account of the complementary relation of love and justice.
Pancreatic cancer: optimizing treatment options, new, and emerging targeted therapies

Pancreatic cancer is the fourth leading cause of cancer death in the US and is expected to become the second leading cause of cancer-related deaths in the next decade. Despite 5-fluorouracil/leucovorin with irinotecan and oxaliplatin (FOLFIRINOX) and gemcitabine/nab-paclitaxel significantly improving outcomes for metastatic cancer, refractory disease still poses significant challenges. Difficulties with early detection and the inherent chemo- and radio-resistant nature of this malignancy led to attempts to define the sequential biology of pancreatic cancer in order to improve survival outcomes. Pancreatic adenocarcinoma is characterized by several germline or acquired genetic mutations, the most common being KRAS (90%), CDK2NA (90%), TP53 (75%-90%), DPC4/SMAD4 (50%). In addition, the tumor microenvironment, chemoresistant cancer stem cells, and the desmoplastic stroma have been the target of some promising clinical investigations. Among the core pathways reproducibly shown to lead the development and progression of this disease, DNA repair, apoptosis, G1/S cell cycle transition, KRAS, Wnt, Notch, Hedgehog, TGF-beta, and other cell invasion pathways, have been the target of "precision therapeutics". No single molecularly targeted therapeutic though has been uniformly successful, probably due to the tumor heterogeneity, but biomarker research is evolving and it hopes to select more patients likely to benefit. Recent reports note activity with immunotherapies such as CD40 agonists, CCR2 inhibitors, cancer vaccines, and novel combinations against the immunosuppressive tumor milieu are ongoing. While many obstacles still exist, clearly we are making progress in deciphering the heterogeneity within pancreatic cancers. Integrating conventional and immunological targeting will be the key to effective treatment of this deadly disease.
Issues related to time averaging of exposure in modeling risks associated with intermittent exposures to lead.

Typical exposures to lead often involve a mix of long-term exposures to relatively constant exposure levels (e.g., residential yard soil and indoor dust) and highly intermittent exposures at other locations (e.g., seasonal recreational visits to a park). These types of exposures can be expected to result in blood lead concentrations that vary on a temporal scale with the intermittent exposure pattern. Prediction of short-term (or seasonal) blood lead concentrations arising from highly variable intermittent exposures requires a model that can reliably simulate lead exposures and biokinetics on a temporal scale that matches that of the exposure events of interest. If exposure model averaging times (EMATs) of the model exceed the shortest exposure duration that characterizes the intermittent exposure, uncertainties will be introduced into risk estimates because the exposure concentration used as input to the model must be time averaged to account for the intermittent nature of the exposure. We have used simulation as a means of determining the potential magnitude of these uncertainties. Simulations using models having various EMATs have allowed exploration of the strengths and weaknesses of various approaches to time averaging of exposures and impact on risk estimates associated with intermittent exposures to lead in soil. The International Commission of Radiological Protection (ICRP) model of lead pharmacokinetics in humans simulates lead intakes that can vary in intensity over time spans as small as one day, allowing for the simulation of intermittent exposures to lead as a series of discrete daily exposure events. The ICRP model was used to compare the outcomes (blood lead concentration) of various time-averaging adjustments for approximating the time-averaged intake of lead associated with various intermittent exposure patterns. Results of these analyses suggest that standard approaches to time averaging (e.g., U.S. EPA) ( 1 ) that estimate the long-term daily exposure concentration can, in some cases, result in substantial underprediction of short-term variations in blood lead concentrations when used in models that operate with EMATs exceeding the shortest exposure duration that characterizes the intermittent exposure. Alternative time-averaging approaches recommended for use in lead risk assessment(2) more reliably predict short-term periodic (e.g., seasonal) elevations in blood lead concentration that might result from intermittent exposures. In general, risk estimates will be improved by simulation on shorter time scales that more closely approximate the actual temporal dynamics of the exposure.
Simplicial cells in arrangements of hyperplanes

Let ℋ be an arrangement of n hyperplanes in Pd, C(ℋ) its cell complex, and H any hyperplane of ℋ. It is proved: (1) If ℋ is not a near pencil then there are at least n−d−1 simplicial d-cells of C(ℋ), each having no facet in H. (2) There are at least d+1 simplicial d-cells of C(ℋ), each having a facet in H.
Potential role of MCP-1 in endothelial cell tight junction `opening': signaling via Rho and Rho kinase

The expression of the monocyte chemoattractant protein-1 (MCP-1) receptor CCR2 by brain endothelial cells suggests that MCP-1 may have other functions than purely driving leukocyte migration into brain parenchyma during inflammation. This study examines one of these potential novel roles of MCP-1 regulation of endothelial permeability using primary cultures of mouse brain endothelial cells. MCP-1 induces reorganization of actin cytoskeleton (stress fiber formation) and redistribution of tight junction proteins, ZO-1, ZO-2 occludin and claudin-5, from the Triton X-100-soluble to the Triton X-100-insoluble fractions. These morphological changes are associated with a decrease in transendothelial electrical membrane resistance and an increase in [14C]inulin permeability. MCP-1 did not induce these events in brain endothelial cells prepared from mice genotype CCR2-/-. The Rho kinase inhibitor Y27632 and inhibition of Rho (C3 exoenzyme, and dominant negative mutant of Rho, RhoT19N) prevented MCP-1-induced stress fiber assembly, reorganization of tight junction proteins and alterations in endothelial permeability. In all, this suggests that a small GTPase Rho and Rho kinase have a pivotal role in MCP-1-induced junction disarrangement. These data are the first to strongly suggest that MCP-1, via CCR2 present on brain endothelial cells, contributes to increased brain endothelial permeability.
Dual-energy electronic scanning-slit fluorography for the determination of vertebral bone mineral content.

A technique for performing accurate bone mineral content (BMC) determination, using dual‐energy scanning‐slit fluorography, has been developed. X‐ray scatter and veiling glare are suppressed using a multiple scanning‐slit device interfaced to a conventional digital subtraction angiography system. The technique employs a pair of calibration step wedges, one tissue and one bone equivalent. The proper use of the step wedges obviates the need for accurate kVp calibration or absolute calibration of the system’s response to BMC. Phantom studies intended to simulate vertebral BMC measurement indicate that the technique is capable of measuring BMC with less than 30 mg/cm2 inaccuracy over a wide range of BMC.
Formal Art Observation Training Improves Medical Students’ Visual Diagnostic Skills

Background Despite evidence of inadequate physical examination skills among medical students, teaching these skills has declined. One method of enhancing inspection skills is teaching “visual literacy,” the ability to reason physiology and pathophysiology from careful and unbiased observation.
1656 IMPROVEMEMT IN PULMONARY INTEPSTITIAL EMPHYSEMA WITH HIGH FREQUENCY VENTIIATION

We have used high frequency ventilation (8-12 Hz or 480-720 cycles/min) to treat five infants with severe pulmonary interstitial emphysema (PIE). All infants were recovering from severe respiratory distress syndrome when X-ray evidence of PIE and blood gas deterioration were noted. The infants had gestational ages of 28-32 weeks, birthweights of 1.0-1.7 kg, and were treated starting at 3-12 days of age. Four of the infants were maintained on the high frequency ventilator for approximately 48 hours, and one for 26 days. FIO2 averaged 0.74 and peak inspiratory pressure 38 cm H2O during conventional ventilation immediately prior to high frequency ventilation. All infants demonstrated prompt improvement in blood gases reaching an average 60 torr increase in PO2 and a 20 torr decrease in PCO2 within one hour. Peak pressure measured in the trachea near the carina fell from 38 to 20 cm H2O. All infants showed resolution of chest X-ray evidence of PIE. Attempts to reinstitute conventional respirator therapy resulted in reoccurrence of PIE in two cases. Two infants weaned rapidly from all respiratory support, one weaned slowly and two died after two days of initial improvement. We conclude that because of the low airway pressures required, high frequency ventilation can be life saving in the treatment of pulmonary interstitial emphysema.
PPARα gene polymorphisms modulate the association between physical activity and cardiometabolic risk.

Abstract Background and aims Habitual physical activity is understood to help prevent type 2 diabetes and atherosclerotic cardiovascular disease via beneficial effects on both metabolism and the vascular system. However, individuals do not have uniform cardiometabolic responses to physical activity. Here we explore the extent to which variation in the proliferator-activated receptor-alpha ( PPARα ) gene, which modulates carbohydrate and lipid metabolism, vascular function, and inflammation, predicts the overall cardiometabolic risk (CMR) profile of individuals engaging in various levels of physical activity. Methods and results 917 unrelated, community volunteers (52% female, of Non-Hispanic European ancestry) aged 30–54 years, participated in the cross-sectional study. Subjects were genotyped for 5 single nucleotide polymorphisms in the PPARα gene, from which common haplotypes were defined. A continuous measure of CMR was calculated as an aggregate of 5 traditional risk factors: waist circumference, resting blood pressure, fasting serum triglycerides, HDL-cholesterol and glucose. Regression models were used to examine the main and interactive effects of physical activity and genetic variation on CMR. One common PPARα haplotype (H-23) was associated with a higher CMR. This association was moderated by daily physical activity ( B = −0.11, SE = 0.053, t = −2.05, P = 0.04). Increased physical activity was associated with a steeper reduction of CMR in persons carrying the otherwise detrimental H-23 haplotype. Conclusions Variations in the PPARα gene appear to magnify the cardiometabolic benefits of habitual physical activity.
Second-generation hybrid D-strut

This paper describes the efforts by Honeywell and MIT to develop a second generation hybrid D-StrutTM (patent pending). The D-Strut is a passive viscous damping and stiffening device used for structural control and isolation. The concept of using an active element synergistically with passive elements was presented in the 1994 SPIE Conference on Smart Structures and Materials paper titled `Actuator with Built-in Viscous Damping for Isolation and Structural Control.' A second generation hybrid D-Strut or active D-Strut with many applications to isolation of spacecraft hardware has been built and tested. The utilization of the device for several system applications is discussed. The primary advantage of the hybrid is that the passive elements are designed for small gravity sag and acceptable mount resonance and the active control is designed to reduce transmissibility over broad or narrow frequency ranges. The payload is then robustly isolated even in the unpowered (active stage off) state. Modeling, dynamic tests, and several single axis isolation experimental results are presented. Also, specific designs for six-axis implementations for microgravity isolation and optical payload isolation, pointing, and suppression are described.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Fresh Water Whitecaps

Abstract Photographic observations of the whitecap coverage of large fresh water lakes were made in conjunction with measurements of wind velocity, and air and surface water temperatures. The fraction of the water surface covered by whitecaps shows an abrupt increase as the wind velocity increases from ∼7 to ∼8 m sec−1. This abrupt change is qualitatively in accord with the published observations of “critical” wind velocities associated with numerous other water-surface and surface-related phenomena. The whitecap coverage of fresh water bodies, particularly at the higher wind velocities, is much less than the published values of whitecap coverage of oceans under the same wind conditions.
Quality of life after treatment for localized prostate cancer: differences based on treatment modality.

Purpose: Brachytherapy with 103palladium (103Pd) is an increasingly administered treatment modality for localized prostate cancer. We compared general and disease specific health related quality of life after 103Pd treatment, radical prostatectomy and external beam radiation therapy given during the same time frame.Materials and Methods: We performed a retrospective cross-sectional survey study of patients treated at a single community medical center between 1995 and 1999. We mailed 5 validated health related quality of life survey instruments to 269, 142 and 222 men who underwent radical prostatectomy, 103Pd treatment and external beam radiation therapy, respectively, with a response rate of greater than 80% in all groups.Results: General health related quality of life assessed by the SF-36 showed the same scores in patients who underwent prostatectomy and 103Pd treatment. The University of California-Los Angeles Prostate Cancer Index was used to assess bowel, urinary and sexual function/bothersomeness. ...
Nickel carbonyl. Effects upon the ultrastructure of hepatic parenchymal cells.

The acute pathologic reactions of hepatic parenchymal cells following exposure to nickel carbonyl (Ni[CO]4) were investigated by electron microscopy. Nickel carbonyl was administered intravenously ...
Electrode Shaping for Ion and Electron Extractors

A technique has been developed that defines the shapes of electrodes needed to produce a good-quality cylindrically symmetric beam of ions or electrons. This work was motivated by the need to optimize electrode shapes for a high-brightness, low-energy, deuteron injector. Our experience had indicated that correct shaping of electrodes becomes increasingly important as beam perveance increases. This provided the motivation for developing a computer program that could specify electrodes producing optimum or improved beam quality. Several techniques have been developed and evaluated. The procedure described here has been very successful in meeting our design goals.
Cross-Border Lease Financing with Japanese Leveraged Leases

This article analyzes Japanese leveraged leases (JLLs), which have been growing in importance as a method of financing numerous types of assets. JLLs were temporarily placed on hold in response to the 2005 tax reforms, but are about to experience resurgence after a recent tax amendment. Specifically, we examine the financial and related issues including the recent tax reforms that a lessee needs to evaluate when financing an asset utilizing the JLL. We discuss the intricacies of the JLL attributes and structures, and develop a valuation model from a lessee9s perspective for evaluating a JLL. This model can be extended to other types of cross-border leases. Finally, we illustrate the evaluation of a JLL utilizing our model with an example in which we derive cash flows, identify the critical variables, and evaluate their impact on the net present value of the lease.
Dynamic correlations in a classical two-dimensional Heisenberg antiferromagnet

A Monte Carlo molecular-dynamics calculation of the dynamic structure function S(q,\ensuremath{\omega}) for the classical two-dimensional isotropic Heisenberg antiferromagnet is presented. For wave vectors near the antiferromagnetic Bragg point, S(q,\ensuremath{\omega}) is well described by a product of Lorentzians representing damped spin waves. For adequately low temperatures, the dependence of the spin-wave frequency and damping on wave vector and temperature are consistent with a dynamic scaling description of Chakravarty, Halperin, and Nelson. Even for higher temperatures a scaling description is quite well satisfied, but with a modified scaling frequency.
A parallel branch-and-cut approach for detailed placement

We introduce a technique that utilizes distributing computing resources for the efficient optimization of a traditional physical design problem. Specifically, we present a detailed placement strategy designed to exploit distributed computing environments, where the additional computing resources are employed in parallel to improve the optimization time. A Mixed Integer Programming (MIP) model and branch-and-cut optimization strategy are employed to solve the standard cell placement problem. By exploiting the problem structure, our algorithm improves upon the solutions afforded by existing optimization algorithms. First, an efficient batch-branching technique can eliminate several integer decision variables during each step of the optimization procedure. This batch-branching scheme can be performed serially or in parallel. In addition, custom cutting-planes are shown to significantly reduce the run time for optimizations as they efficiently refine the feasible region in order to quickly produce integer solutions. Our serial branch-and-cut strategies allow for significant reductions in wirelength, relative to the state-of-the-art commercial software package CPLEX, assuming a fixed allotment of time. Furthermore, we show that distributed computing resources can be used to significantly reduce the time required to achieve reductions in wirelength.
Early U.S. interest in hypersonic flight.

In David Malakoff's article “Mach 12 by 2012?” (News Focus, 9 May, p. [888][1]), he dates U.S. government interest in hypersonic flight to Army research in 1949 using a World War II Nazi V-2 rocket. In fact, in NASA's predecessor, the National Advisory Committee for Aeronautics (NACA), that terror weapon inspired hypersonic research just as the war was ending. NACA engineer John V. Becker, later a leader of hypersonic X-15 research, wrote that the “eventual need for a wind tunnel capable of speeds in the range of 5 to 10 times the speed of sound was envisioned in 1945,” and that ensuing efforts led by 1947 to an operational hypersonic tunnel at what is now called NASA Langley Research Center [([1][2]), pp. 619-620; ([2][3]), pp. [344][4]-347]. 1. 1.[↵][5] 1. J. V. Becker , J. Appl. Phys. 21, 619 (950). 2. 2.[↵][6] 1. J. R. Hansen , Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917–1958 (NASA SP-4305, Scientific and Technical Information Office, NASA, Washington, DC, 1987). [1]: /lookup/doi/10.1126/science.300.5621.888 [2]: #ref-1 [3]: #ref-2 [4]: /lookup/doi/10.1126/science.1086534 [5]: #xref-ref-1-1 "View reference 1. in text" [6]: #xref-ref-2-1 "View reference 2. in text"
f-State luminescence of trivalent lanthanide and actinide ions in solution

Detailed studies of the luminescence of aquated Am 3+ are presented in the context of prior work on lanthanide and actinide ions. The luminescing state of aquated Am 3+ is confirmed to be 5 D 1 based on observed emission and excitation spectra. The luminescence lifetime of Am 3+ in H 2 O solution is (22±3) ns and (155±4) ns in D 2 O solution at 295 K. Judd-Ofelt transition intensity theory qualitatively describes the observed Am 3+ relative integrated fluorescence intensities. Recent luminescence studies on complexed trivalent f-element ions in solution are reviewed as to the similarities and differences between the lanthanide ion 4f state and the actinide ion 5f state properties
Comparing Scores on Spatial-Perception Tests for Intercollegiate Athletes and Nonathletes

Many researchers believe that the amount of testosterone in the blood is directly associated with visuospatial perception. If this is the case, men and women who participate in intercollegiate athletics (and have high androgen levels) should show significantly better spatial ability than nonathletes. Two paper-and-pencil tests to measure spatial ability were given to 200 men and women on university sport teams. Men's scores, compared to national norms, were significantly lower than those in the national sample but no difference was found between the women athletes and the national sample or between the male and female athletes.
3-D CT angiographic demonstration of a neonatal ductus arteriosus aneurysm with development of ductal calcification: are the "ductus bump", ductus arteriosus aneurysm, and ductal calcification related?

A “ductus bump” was noted as an incidental finding on a chest radiograph in a newborn infant with congenital cystic adenomatoid malformation. A chest CT performed on the first day of life demonstrated this to be a ductus arteriosus aneurysm (DAA), which subsequently thrombosed. Ductal calcification was noted on follow-up imaging. We propose that the “ductus bump” may actually be a DAA, which resolves presumably by thrombus formation. Ductal calcification may also be related to the regression of the thrombus.
Public Attitudes Toward the Census: Influences and Trends*

Objective. This article considers the determinants of attitudes toward the census. Methods. Data from a survey of Connecticut residents are analyzed. Some of the questions replicate items from previous national surveys. Results. Conservatives and people with low trust in government have more negative views of the census, while interest in politics has no effect. Exposure to advertising has a positive effect on some attitudes. Conclusions. Despite the Census Bureau's efforts to maintain political neutrality, support of the census is influenced by general outlook on government and politics, suggesting that conflicts over the census are likely to continue.
Sexual Outlaws: Queer in a Funny Way

The most important feminist cultural work done by mass-mediated women comedians of the last generation has been a result of their subversions of heteronormativity. Over the last 30 years or so, the...
Analyses of hydrogen sorption kinetics and thermodynamics of magnesium–misch metal alloys

Abstract The multi-component Mg– x wt.% Mm alloys are synthesized using the mechanical ball-milling technique and their hydrogen storage capacities, absorption/desorption kinetics, and thermodynamic parameters are quantified. The analysis of kinetic properties presented here is based on the method of exponential peeling. It is seen that the presence of misch metal (Mm) in the alloy samples dramatically decreases their rate of decrepitation and increases their cyclic stability. However, the increased concentration of misch metal in the samples has an adverse effect on their hydrogen storage capacity and their reaction rate. The hydrogen storage properties also vary with reaction temperature. The best hydrogen absorption kinetics are observed at temperatures around 300 °C and the desorption kinetics are quite fast at temperatures of 400 °C and above. The hydrogen desorption activation energy of Mg– x wt.% Mm hydride is much lower than that of MgH 2 . The pressure–composition–isotherm ( P – C – T ) plots of the samples at 300–420 °C indicate that the alloys possess good cyclic stability but very poor reversibility, making the study of their thermodynamic properties difficult. The P – C – T plots also indicate that the increase of the concentration of the misch metal's rare earths leads to an increase of the hydrogen equilibrium pressure and decrease of hydrogen storage capacity.