cssi/SciSciGPT-SciSciNet huggingface dataset:
Machine learning to predict properties of fresh and hardened alkali-activated concrete

Abstract Alkali-activated concrete (AAC) is widely considered to be a sustainable alternative to Portland cement concrete. However, on account of extensive heterogeneity in composition of the aluminosilicates, coupled with the failure of classical materials science approaches to unravel the underlying composition-property linkages, reliable prediction of AAC's properties has remained infeasible. This paper presents a random forest (RF) model to predict two properties of fly ash-based AACs that are important from compliance standpoint – slump flow; and compressive strength – in relation to physiochemical attributes, curing conditions, and mixing procedures of the concretes. Results show that the RF model – once meticulously trained, and after its hyperparameters are rigorously optimized – is able to produce high fidelity predictions of both properties of new AACs. The model is also used to quantitatively assess the influence of physiochemical attributes and process parameters on the AAC's properties. Outcomes of this work present a pathway to optimization of AACs' properties.
A vacuum ultraviolet photoionization study on the isomerization, decomposition, and molecular mass growth processes in solid nitromethane (CH3NO2)

Abstract In this Feature Article, we highlight the crucial findings from experimental and theoretical studies investigating the dissociation mechanisms of condensed phase nitromethane (CH3NO2), a model compound of nitro-hydrocarbon (R-NO2) based energetic material. Our findings on intriguing isomerization, decomposition and molecular mass growth pathways of nitromethane are placed into perspective by exploiting complementary spectroscopy probes such as Fourier Transform Infrared Spectroscopy (FTIR), Electron Paramagnetic Resonance (EPR), and single-photon isomer selective photoionization reflectron time-of-flight mass spectrometry (PI-ReTOF-MS) in conjunction with quantum chemical calculations. These investigations unravel the isomerization of nitromethane to exotic isomers such as aci-nitromethane, nitrosomethanol, and N-hydroxyoxaziridine. Evidence of non-equilibrium decomposition channels involving suprathermal oxygen, hydrogen and carbene formation are also revealed. Finally, involvement of these radical species in molecular mass growth processes leading to higher molecular weight products are emphasized. Benchmark studies established from a ‘simple’ nitromethane system are highly beneficial to predict the decomposition mechanisms of ‘real’ explosives.
Incidence and risk factors of venous thromboembolism in ANCA-associated vasculitis: a metaanalysis and metaregression

The incidence of venous thromboembolism (VTE) in ANCA-associated vasculitis patients varies in different populations. Moreover, the risk factors for VTE in these patients are poorly described due to the small number of events. Ovid MEDLINE, EMBASE, and the Cochrane Library were searched for eligible articles. The inclusion criteria included observational studies that enrolled patients age ≥ 18 years diagnosed with ANCA-associated vasculitis. The incidence of VTE is the outcome of interest. Of 1362 citations, a total of 21 studies (n = 4422) dated from 2006 to 2019 were included in the systematic review. The mean age was 54.2 ± 4.0 years. Most were male (52.0%) and Caucasian (80.9%). With a mean follow-up duration of 5.2 ± 2.8 years, the pooled incidence of VTE in ANCA-associated vasculitis patients was 12.4% (95% CI, 8.8–17.2). Of these, 63.4% (95% CI, 57.3–69.1) had deep vein thrombosis and 26.3% (95% CI, 17.6–37.4) had pulmonary embolism. Recurrent VTE occurred in 10.0% (95% CI, 5.2–18.6). From the metaregression adjusted for age, sex, and ethnicity; positive MPO-ANCA, increasing Birmingham Vasculitis Activity Score at time of vasculitis diagnosis, and presence of renal involvement were positively associated with increased VTE events. Positive PR3-ANCA profile was inversely associated with increased VTE events. Increasing follow-up duration was not associated with increased VTE events. VTE in ANCA-associated vasculitis is common. Positive MPO-ANCA, increasing vasculitis activity, and presence of renal involvement were significant risk factors for VTE while positive PR3-ANCA was inversely associated with increased VTE.
Exploring Predictors of Social Distancing Compliance in the United States during the COVID-19 Pandemic.

OBJECTIVE Through the application of the Health Belief Model, this study sought to explore how relationships between perceived susceptibility, severity, and benefits of social distancing recommendations, as well as psychological factors, may impact compliance with COVID-19 social distancing recommendations in the United States. METHODS Between October and November 2020, a convenience sample of English-speaking adults in the United States completed an online, cross-sectional survey which included items assessing beliefs around threats (e.g., perceived susceptibility and severity), response efficacy (e.g., perceived benefits), psychological factors (e.g., stress and COVID-specific anxiety), and compliance with social distancing measures (e.g., avoiding social gatherings). RESULTS Social distancing compliance was positively associated with perceived susceptibility of COVID-19 (b = 0.42, P < 0.05) and perceived benefits of social distancing recommendations (b = 0.81, P < 0.01). No significant associations were found between perceived severity of COVID-19 (P = 0.38), general stress (P = 0.28), COVID-19-related anxiety (P = 0.12), and compliance. CONCLUSIONS Findings suggest that perceived susceptibility to COVID-19 and perceived benefits of social distancing measures significantly increased compliance with social distancing recommendations in this convenience sample of U.S. adults.
Infant Deaths From Medical Causes After a Maltreatment Report.

OBJECTIVES To examine whether postneonatal infants reported for maltreatment face a heightened risk of deaths attributable to medical causes. METHODS Birth and death records for all children born in California between 2010 and 2016 (N = 3455985) were linked to administrative child protection system records. Infants were prospectively followed from birth through death or age 1 year. Reports of maltreatment and foster care placement episodes were modeled as time-varying covariates; sociodemographic characteristics at birth were modeled as baseline covariates. Stratified, multivariable competing risk models were used to estimate the adjusted relative hazard of postneonatal infant death attributed to a medical cause (n = 1051). RESULTS After adjusting for baseline risk factors, and compared with infants never reported for maltreatment, the medical-related mortality risk was almost twice as great among infants reported once for maltreatment (hazard ratio: 1.77; 95% confidence interval: 1.36–2.30) and 3 times greater if there was >1 maltreatment report (hazard ratio: 3.27; 95% confidence interval: 2.48, 4.30). Among infants reported for maltreatment, periods of foster care placement reduced the risk of death by roughly half. CONCLUSION Infants reported for alleged maltreatment had a higher risk of death from medical causes, with foster care emerging as protective. Targeted support services for parents and improved communication between the child protection system and the pediatric health care community is needed, especially when infants who may be medically fragile and remain at home after an allegation of abuse or neglect.
Experimental investigation of the aerodynamics of a large industrial building with parapet

The aerodynamic performance of a roof depends significantly on its shape and size, among other factors. For instance, large roofs of industrial low-rise buildings may behave differently compared to those of residential homes. The main objective of this study is to experimentally investigate how perimeter solid parapets can alter the flow pattern around a low-rise building with a large aspect ratio of width/height of about 7.6, the case of industrial buildings/shopping centers. Solid parapets of varied sizes are added to the roof and tested in an open-jet simulator in a comparative study to understand their impact on roof pressure coefficients. Roof pressures were measured in the laboratory for cases with and without parapets under different wind direction angles (representative of straight-line winds under open terrain conditions). The results show that using a parapet can alter wind pressures on large roofs. Parapets can modify the flow pattern around buildings and change the mean and peak pressures. The mean pressure pattern shows a reduction in the length of the separation bubble due to the parapet. The parapet of 14% of the building’s roof height is the most efficient at reducing mean and peak pressures compared to other parapet heights.
Unified View of Diffusion and Dispersion

Diffusion and dispersion are basically convective transport mechanisms. The method chosen for representing the convection in a mass balance equation is the determining factor in deciding whether diffusion or dispersion must be included in the conservation equation for a given flow. This principle is illustrated for molecular diffusion, turbulent diffusion, and longitudinal dispersion. In a given flow, the relative importance of diffusion or disperion in different transport problems depends on the steepness of the concentration gradient. It is proposed that the term diffusion be reserved for transport that is associated primarily with time-averaged velocity fluctuations and that dispersion be used for transport associated primarily with the spatial average of velocity variations.
DISCUSSION OF BODY-FORCE STRESSES IN GRAVITY STRUCTURES

THE AUTHORS PRESENTED USEFUL RESULTS OF EXPERIMENTS ON THE DETERMINATION OF STRESS IN GRAVITY STRUCTURES USING PHOTOELASTIC ANALYSIS. HOWEVER, CERTAIN FEATURES OF THE ANALYSIS DESCRIBED CAST DOUBT ON THE VALIDITY OF THE ANALYTICAL RESULTS. AMONG THESE ARE: (1) THE RESULTS FOR STRESS DISTRIBUTION GIVEN BY AN EQUATION ARE ESSENTIALLY SIMILAR TO THOSE GIVEN BY LEVY, HOWEVER, THE LINEARITY OF THE RESULTING STRESS DISTRIBUTION DOES NOT RESULT FROM LEVY'S ANALYSIS, BUT IS ONE OF HIS INITIAL ASSUMPTIONS, (2) THE STRESS FUNCTION DEFINED MAY BE VALID FOR PLANE STRESS, OR FOR INCOMPRESSIBLE MATERIALS UNDER PLANE STRAIN CONDITIONS, HOWEVER, THE STRESS FUNCTION DOES NOT APPEAR GENERALLY COMPLETE FOR MATERIALS WITH POISSON'S RATIO LESS THAN 1/2 AND PLANE STRAIN CONDITIONS. THE STRESS FUNCTION SHOULD INCLUDE A TERM INCORPORATING POISSON'S RATIO. FIGURES ARE PRESENTED ON THE DISTRIBUTION OF VERTICAL NORMAL STRESS AND A COMPARISON OF ANALYTICAL AND EXPERIMENTAL DETERMINATION OF PRINCIPAL STRESS ON UPSTREAM FACE OF ELASTIC EARTH DAM. IT IS SUGGESTED THAT THE AUTHORS MAY WISH TO RECONSIDER THEIR CONCLUSIONS CONCERNING THE CURRENT STATE OF ANALYTICAL THEORY, AND THE APPLICABILITY OF EXISTING THEORY TO THE SOLUTION F PRACTICAL PROBLEMS. REFERENCES: BODY-FORCE STRESSES IN GRAVITY STRUCTURES, ROWLAND RICHARDS, JR. AND WERNER E. SCHMID, ASCE (PROC. PAPER 5749), JANUARY, 1968.
Formation of Reactive Metabolites of Foreign Compounds and their Covalent Binding to Cellular Constituents

The sections in this article are: 1 Theoretical Considerations 2 Examples 2.1 Acetaminophen 2.2 Bromobenzene 2.3 Furosemide 2.4 Isoniazid and Iproniazid 3 Conclusion
Angular wander measurements of maser clusters

Angular wander measurements of the relative positions of closely spaced maser features provides a powerful probe of interstellar turbulence associated with regions of star formation. Differential angular wander is easily measured in a maser complex and can strongly distinguish between shallow and steep power-law turbulence. The best candidates for such measurements appear to be the 6 and 12 GHz type II methanol masers.
The destruction of the maternal and fetal pituitary glands in subhuman primates

Abstract 1. 1. A technique is presented by which it is possible to destroy the pituitary gland of the intrauterine primate fetus in the second trimester of pregnancy. 2. 2. Destruction of the maternal hypophysis was achieved by the transsphenoidal placement of Y90 pellets in pregnant monkeys. 3. 3. In 3 animals both fetal and maternal Y90 hypophysectomies were carried out in the same pregnancy. 4. 4. Clinical observations regarding the subsequent course of pregnancy as well as the pathologic confirmation of pituitary destruction are discussed. 5. 5. The placenta appears sufficient to sustain apparently normal gestation in monkeys after both the fetal and maternal hypophyses have been destroyed in the second trimester of pregnancy.
An Analysis of the Effects of Health Insurer Monopsony Power on Primary Care Physician Practices

Consolidation of health insurers has generated significant concern that insurers are using monopsony power. This paper ascertains if monopsony power affects physician markets for primary care physicians. Physicians change having increased willingness to accept new Medicare patients, perception of Medicare reimbursement inadequacy and change volume of physician services in more concentrated insurer markets. However, physicians also have a lower percentage of practice revenues originating from private payers, increased levels of acceptance of new Medicaid recipients, and reduced perception of Medicaid payment inadequacy. Insurer concentration also leads physicians to integrate into multi-physician practices, affiliate with hospitals, and accept salaried financial arrangements
Chapter 18 NMR, EPR and mössbauer effect: Metals, alloys and compounds

Publisher Summary This chapter discusses the methods of nuclear magnetic resonance (NMR) and of Mossbauer effect or nuclear gamma resonance (NGR) spectroscopy for the study of the structural, electronic, and magnetic properties of rare-earth metals, alloys, and compounds. A variety of other nuclear techniques based on nuclear orientation (NO) and perturbed angular correlation (PAC) of gamma radiation are discussed that are gaining increasing significance in solid state investigations. To serve as a basis for the discussion of experimental results, the natural abundances, spins, effective gyromagnetic ratios, and electric quadrupole moments of the ground states of those nuclei, rare-earth and non-rare earth, significant for the study of rare-earth metals, alloys, and compounds, are listed in the tables in the chapter. The principal interactions that contribute to the nuclear spin relaxation times in NMR experiments are briefly considered, and the connections among these and the parameters characterizing the steady-state spectrum are discussed in the chapter.
Atmospheric deposition of inorganic and organic nitrogen and base cations in Hawaii

[1] Atmospheric deposition of nitrogen (N) and base cations was measured for 5–7 years on the island of Hawaii and for 1.5 years on Kauai. On Hawaii, mean annual fluxes of K+, Mg2+, and Ca2+ were 15, 17, and 13 kg ha−1 yr−1, respectively. Fog interception was the largest deposition pathway. Sea salt contributed the majority of cations, although biomass burning and Asian dust were significant sources for some years. Total N deposition (inorganic and organic) averaged 17 kg N ha−1 yr−1. Fog interception was also the largest source of N, depositing 16 kg N ha−1 yr−1. Precipitation deposition was 1.0 and 0.2 kg N ha−1 yr−1, respectively on Hawaii and Kauai. Dry deposition on Hawaii was 0.1 kg N ha−1 yr−1. Organic N averaged 16 and 12% of total N in rain and fog, respectively. The δ15N values for NO3−-N are consistent with long-range transport of N from Asia in the spring/summer and from North America in the fall/winter as nonvolcanic sources. Atmospheric deposition on Hawaii may completely account for a previously identified soil N imbalance.
On Logics of Knowledge and Belief

Formal epistemology, or at least the approach to formal epistemology that develops a logic and formal semantics of knowledge and belief in the possible worlds framework, began with Jaakko Hintikka’s book Knowledge and Belief, published in 1962. It was later developed and applied to problems in theoretical computer science and game theory, as well as within epistemology. This paper surveys some of these developments, focusing on the formal relations between knowledge and belief, and on the way that the logics of knowledge and belief connect with some traditional problems in epistemology.
Reduced aspartate release from rat hippocampal synaptosomes loaded with Clostridial toxin light chain by electroporation: evidence for an exocytotic mechanism.

Aspartate can be released from certain hippocampal pathways along with glutamate or GABA. Although aspartate immunoreactivity has been localized to synaptic vesicles and aspartate release is Ca2+-dependent, there has been no clear evidence favoring an exocytotic mechanism. In particular, pretreatment with Clostridial toxins has not consistently inhibited aspartate release, even when release of glutamate from the same tissue samples was markedly inhibited. To address this issue directly, rat hippocampal synaptosomes were permeabilized transiently by electroporation in the presence of active or inactivated Clostridial toxin light chains. Loading rat hippocampal synaptosomes with the active light chain of tetanus toxin or of botulinum neurotoxins A, B or C reduced the K+-evoked release of aspartate at least as much as that of glutamate. These results confirm that aspartate is released by exocytosis in rat hippocampus.
Individualized computer-based surgical planning to address pulmonary arteriovenous malformations in patients with a single ventricle with an interrupted inferior vena cava and azygous continuation

Objective Pulmonary arteriovenous malformations caused by abnormal hepatic flow distribution can develop in patients with a single ventricle with an interrupted inferior vena cava. However, preoperatively determining the hepatic baffle design that optimizes hepatic flow distribution is far from trivial. The current study combines virtual surgery and numeric simulations to identify potential surgical strategies for patients with an interrupted inferior vena cava. Methods Five patients with an interrupted inferior vena cava and severe pulmonary arteriovenous malformations were enrolled. Their in vivo anatomies were reconstructed from magnetic resonance imaging (n = 4) and computed tomography (n = 1), and alternate virtual surgery options (intracardiac/extracardiac, Y-grafts, hepato-to-azygous shunts, and azygous-to-hepatic shunts) were generated for each. Hepatic flow distribution was assessed for all options using a fully validated computational flow solver. Results For patients with a single superior vena cava (n = 3), intracardiac/extracardiac connections proved dangerous, because even a small left or right offset led to a highly preferential hepatic flow distribution to the associated lung. The best results were obtained with either a Y-graft spanning the Kawashima to split the flow or hepato-to-azygous shunts to promote mixing. For patients with bilateral superior vena cavae (n = 2), results depended on the balance between the left and right superior inflows. When those were equal, connecting the hepatic baffle between the superior vena cavae performed well, but other options should be pursued otherwise. Conclusions This study demonstrates how virtual surgery environments can benefit the clinical community, especially for patients with a single ventricle with an interrupted inferior vena cava. Furthermore, the sensitivity of the optimal baffle design to the superior inflows underscores the need to characterize both preoperative anatomy and flows to identify the best option.
Characteristics of existing construction automation and robotics technologies

As a first step in detailed assessment, this research analyzes selected attributes of 85 existing construction automation and robotics technologies to examine certain trends in the development of construction technologies and the attributes of the technologies which can influence their use by construction companies. In general, previously identified priorities for automation are close to being fulfilled, and correspond with opportunities for adoption. Most of the technologies concentrate on areas of identified benefits, and attempt to reduce the complexity associated with adoption through only minimal changes in tasks. In the same way, complementary changes required to use the technologies are kept at a minimum overall. This analysis is used to identify further opportunities for the development and implementation of construction automation and robotics technologies.
Burrow structure and foraging costs in the fossorial rodent, Thomomys bottae

A model for calculating the energy cost of burrowing by fossorial rodents is presented and used to examine the energetics of foraging by burrowing. The pocket gopher Thomomys bottae (Rodentia: Geomyidae) digs burrows for access to food. Feeding tunnels of Thomomys are broken into segments by laterals to the surface that are used to dispose of excavated soil. Energy cost of burrowing depends on both soil type and on burrow structure, defined by the length of burrow segments, angle of ascent of laterals, depth of feeding tunnels, and burrow diameter. In a desert scrub habitat, Thomomys adjust burrow segment length to minimize cost of burrowing. Observed segment lengths (mean=1.33 m) closely approximate the minimum-cost segment length of 1.22 m. Minimizing energy expended per meter of tunnel constructed maximizes efficiency of foraging by burrowing in the desert scrub. Burrow diameter and cost of burrowing increase with body size, while benefits do not, so foraging by burrowing becomes less enconomical as body size increases. Maximum possible body size of fossorial mammals depends on habitat productivity and energy cost of burrowing in local soils.
MEASURES OF PULSATILE ARTERIAL LOAD ARE ASSOCIATED WITH MYOCARDIAL WALL STRESS DURING SYSTOLE

Pulsatile arterial load increases with age and may increase systolic myocardial wall (fiber) stress (σf) in older individuals. We investigated the association of measures of pulsatile load with σf in older adults. We performed arterial tonometry and echocardiography with speckle tracking in 309
The association of body mass index with mortality in the California Teachers Study

Although underweight and obesity have been associated with increased risk of mortality, it remains unclear whether the associations differ by hormone therapy (HT) use and smoking. The authors examined the relationship between body mass index (BMI) and mortality within the California Teachers Study (CTS), specifically considering the impact of HT and smoking. The authors examined the associations of underweight and obesity with risks of all-cause and cause-specific mortality, among 115,433 women participating in the CTS, and specifically examined whether HT use or smoking modifies the effects of obesity. Multivariable Cox proportional hazards regression provided estimates of relative risks (RRs) and 95% confidence intervals (CIs). During follow up, 10,574 deaths occurred. All-cause mortality was increased for underweight (BMI <18.5; adjusted RR = 1.33, 95% CI = 1.20–1.47) and obese participants (BMI ≥ 30: RR = 1.27, 95% CI = 1.19–1.37) relative to BMI of 18.5–24.9). Respiratory disease mortality was increased for underweight and obese participants. Death from any cancer, and breast cancer specifically, and cardiovascular disease was observed only for obese participants. The obesity and mortality association remained after stratification on HT and smoking. Obese participants remained at greater risk for mortality after stratification on menopausal HT and smoking. Obesity was associated with increased all-cause mortality, as well as death from any cancer (including breast), and cardiovascular and respiratory diseases. These findings help to identify groups at risk for BMI-related poor health outcomes.
Detect the dots

This paper presents quantum dots (QDds) and its applications in biomolecular analysis and target detection. Applications include QDs as fluorescent labels, QDs in multiplexed detection in biomolecular analysis, QD-mediated fluorescence resonance energy transfer, and single-particle fluorescence coincidence detection. Continuous advances in surface chemistry and synthesis processes of QDs have greatly improved the reliability of QDs for biomolecular assaying. A number of QD-based biomolecular technologies have been validated with actual clinical samples. This great progress has shown that QDs are amenable to clinical applications and will accelerate the translation of these new technologies into clinical settings.
Nigral dopaminergic neurons: differential sensitivity to apomorphine following long-term treatment with low and high doses of amphetamine.

Abstract Twice daily injections of 1.0 or 5.0 mg/kg d -amphetamine for 6 consecutive days differentially affected the response of dopaminergic neurons in the substantia nigra pars compacta to challenge injections of apomorphine on the following day. Thus, whereas treatment with the high amphetamine dose produced a dramatic shift to the right of the apomorphine dose-response curve, rats treated with 1.0 mg/kg d -amphetamine responded to apomorphine in the same way as saline-treated controls. These results support the view that long-term treatment with relatively high amphetamine doses is required to produce autoreceptor subsensitivity in the substantia nigra.
OPTIMAL SYSTEMS: I. THE VASCULAR SYSTEM

An approach to quantitative work on optimal systems is considered. Desired optimal principles are utilized in constructing a hypothetical system similar to the organ system considered. A comparison of this constructed system with the anatomical system then gives an indication of the importance of the optimal principles in the form or function of the organ system considered.
Defective Myocardial Carnitine Metabolism in Congestive Heart Failure Secondary to Dilated Cardiomyopathy and to Coronary, Hypertensive and Valvular Heart Diseases

Reduced myocardial carnitine concentrations in the explanted heart and elevated plasma levels have been found in patients undergoing heart transplant for end-stage congestive heart failure (CHF). To evaluate a possible loss of myocardial carnitine in less severe stages of CHF, total myocardial carnitine levels were compared in right ventricular endomyocardial biopsies from 28 patients with mild, moderate and severe dilated cardiomyopathy, 8 patients with CHF of different origin and 13 normal control subjects. If possible, free myocardial carnitine and free and total plasma carnitine were also determined. For the first time, myocardial carnitine levels have been measured in endomyocardial biopsies from 13 normal human hearts (control values: 9.9 +/- 0.8 nmol/mg noncollagen protein). In comparison with these control values, total myocardial carnitine was significantly reduced in patients with dilated cardiomyopathy (6.1 +/- 0.5 nmol/mg noncollagen protein, p less than 0.0001), and CHF of other origins (6.6 +/- 1.1 nmol/mg noncollagen protein, p less than 0.02). Free myocardial carnitine concentrations in dilated cardiomyopathy (4.6 +/- 0.4 nmol/mg noncollagen protein) and CHF of different origin (4.4 +/- 0.5 nmol/mg noncollagen protein) were also significantly different from control values (control values: 9.7 +/- 0.7 nmol/mg noncollagen protein, p less than 0.0001 and p less than 0.005 for both groups). The loss of free and total myocardial carnitine was comparable in dilated cardiomyopathy and CHF due to other diseases. In contrast, plasma free and total carnitine levels in the CHF patients were significantly elevated (67 +/- 5.5 mumol/liter, control values 41 +/- 3.7 mumol/liter, p less than 0.005). Alterations in myocardial carnitine metabolism represent nonspecific biochemical markers in CHF with yet unknown consequences for myocardial function.
THE DESIGN OR OPERATION OF AIRCRAFT TO MINIMIZE THEIR SONIC BOOM

Means of reducing or eliminating the sonic boom through aerodynamic design or aircraft operation are discussed. These include designing aircraft to minimize or eliminate certain features of the overpressure signature, operating aircraft at slightly supersonic speeds so that the sonic boom does not reach the ground, and seeking reductions through the high altitude-high speed flight conditions of hypersonic transports. A simple computer program has been developed that determines the area development of the equivalent body of revolution required to minimize various sonic boom signature parameters.
SURFACE ACTIVITY AND EMULSIFICATION PROPERTIES OF SURFACTANTS DERIVED FROM NONYLPHENOL ETHOXYLATED, ETHYLENE OXIDE AND CARBON DIOXIDE

ABSTRACT The synthesis of new water soluble nonylphenol poly(ethylene carbonate) surfactants derived from nonylphenol ethoxylated (NP(EO)10), ethylene oxide (EO), and carbon dioxide was carried out in high yields in the presence of K2SnO3 as a basic catalysts. Synthesis reactions were carried out in a stainless-steel reactor at 175°C at an initial pressure of 800 psi for a 24 h-period. Surfactants were characterized by FTTR, 1H- and 13C-NMR. The percentages of carbon dioxide incorporation obtained were between 5.8 and 10.9, depending on the starting molar ratio of NP(EO)10:EO:CO2. CMC values, as well as cloud points decreased with the molar ratio CO2/EO, indicating a reduction of hydrophilic character of the surfactants due to the addition of carbonate groups, O-C(=O)-O, into the ethoxylated chains. Also, the area per molecule at die interface increased when molar ratio CO2/EO increased, indicating a two site anchoring model for both hydrophobic moieties, poly(ethylene carbonate) chain and nonylphenol. Fi...
Otic axis locator: closing the accuracy gap in cephalometrics and cast mounting.

Abstract An overview is presented of a new technique to improve the accuracy and reproducibility of earpost-dependent orientation in procedures such as cephalometric radiography and cast mounting, using a custom-molded ear canal insert to provide a stable fitted socket for more exact earpost fit. This is especially valuable in follow-up treatment and serial studies because the insert can be filed for future use on the same patient to provide identical positioning in successive registrations. Cephalometric radiography is further enhanced by the addition of a radiopaque x-ray marker deep in the canal, otherwise inaccessible, close to the bony ear canal (anatomical porion) and the mandibular condyle. This marker is also visible in all 3 cephalometric views—lateral, frontal (posteroanterior) and coronal (submental-vertex)—providing an exact common horizontal axis (Otic axis) for a three-dimensional Cartesian coordinate system of measurement. (Am J Orthod Dentofacial Orthop 2000;117:298-302)
Optimal service and arrival rates in Jackson queueing networks

In this paper we present an algorithm for solving a class of queueing network design problems. Specifically, we focus on determining both service and arrival rates in an open Jackson network of queueing stations. This class of problems has been widely studied and used in a variety of applications, but not well solved due to the difficulty of the resulting optimization problems. As an example, consider the classic application in computer network design which involves determining the minimum cost line capacities and flow assignments while satisfying a queueing performance measure such as an upper limit on transmission delay. Other application areas requiring the selection of both service and arrival rates in a network of queues include the design of communication, manufacturing, and health care systems. These applications yield optimization problems that are difficult to solve because typically they are nonconvex, which means they may have many locally optimal solutions that are not necessarily globally optimal. Therefore, to obtain a globally optimal solution, we develop an efficient branch and bound algorithm that takes advantage of the problem structure. Computational testing on randomly generated problems and actual problems from a health care organization indicate that the algorithm is able to solve realistic sized problems in reasonable computing time on a laptop computer. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 1–17, 2000
Temporal summation functions for detection of sine-wave gratings in young and older adults.

Abstract Temporal summation functions for 0.416 and 7.5 c/deg sinusoidal gratings were measured in young and old observers in order to test the hypothesis of a shift in sensitivity from “transient” to “sustained” channels in the aging visual system. Results failed to support the transient-shift hypothesis. Additional tests showed no age-related changes in temporal summation even within a single channel. When all observers were refracted for the test distance and matched for retinal illuminance, no age-related differences in contrast sensitivity were found.
Glomus tumors in patients of advanced age: a conservative approach.

Objectives: Identify and discuss controversies in the management of paragangliomas in elderly patients. Assess and evaluate a conservative treatment strategy involving limited surgical resection and vigilant monitoring of the outcome measures of tumor control, peritreatment morbidity, symptom resolution, and hearing preservation. Study Design: Retrospective case review. Methods: All of the patients in this study were over age 60 with temporal bone glomus tumors. Primary outcome assessment included length of hospitalization, perioperative morbidity, symptom resolution, hearing preservation, and long-term tumor control. Results: Twelve female patients with mean age of 74.5 years (range 61–85 years) with follow-up from 24 months to 33 years (mean/median: 5/7.8 years) were identified. Nine (75%) of the patients presented with pulsatile tinnitus. Seven patients (58%) underwent surgical excision of the middle ear component of the paraganglioma. Tumors extending to the jugular foramen were purposely not resected. Five patients (45%) had relative or absolute contraindications to surgical resection and were treated with observation or primary radiation therapy. Post-treatment audiometric evaluation confirmed stable or improved hearing. Pulsatile tinnitus resolved in all patients. No patient experienced cranial nerve deficits, extended hospitalization, or blood transfusions. All patients were followed closely with radiological imaging. The majority of patients demonstrated no disease or stable disease, while two patients demonstrated tumor growth 6 years after diagnosis. Conclusion: A prolonged natural history and the morbidity associated with surgical intervention have led to controversies in the treatment of glomus tumors in an elderly population. Our experience supports recent limited reports advocating conservative surgical excision and vigilant long-term monitoring in this population.
Performance evaluation of distributed multi-cell beamforming for MU-MIMO systems

Inter-cell interference (ICI) from nearby cells can substantially degrade the sum-rate in WLAN systems. To improve the sum-rate in actual WLAN systems, some papers have investigated distributed multi-cell beamforming to mitigate ICI by zero forcing beamforming. All most of these approaches consider single-user multiple input multiple output (SU-MIMO) systems. In this paper, we present three techniques for distributed multi-cell beamforming for multi-user MIMO (MU-MIMO) systems with the same total number of transmit and receive antennas. The first technique is distributed multi-cell beamforming using receiver selection. The second one is antenna selection at the receiver. The last one is an iterative technique in which transmitter weight is updated at the transmitter to correspond to receiver weight. The sum-rate of these techniques with imperfect channel state information at transmitter (CSIT) is evaluated. We clarify the effectiveness of these techniques for MU-MIMO systems.
The Use of Desmopressin in the Management of Two Patients with von Willebrand's Disease Undergoing Periodontal Surgery. 2 Case Reports

Von Willebrand's disease is a genetic bleeding disorder characterized by either a reduced plasma concentration of von Willebrand's factor (vWF) or a qualitative deficiency in that vWF which is produced. Previous therapy consisted of injecting concentrates of vWF manufactured from the pooled plasma of multiple donors. With the increased incidence and risk of serum borne transmission of such diseases as hepatitis and AIDS, the advantages of an alternative mode of therapy was obvious. In the course of using 1desamino-8-D-argenine (desmopressin or DDAVP, a synthetic analogue of 8-argenine Vasopressin, a hormone secreted in the posterior pituitary gland) in the treatment of diabetes insipidis, it was discovered that this drug causes the release of bound vWF into the plasma. The elevation lasts for several hours and is effective in producing hemostasis in some types of mild to moderate von Willebrand's disease. In 1984, desmopressin was approved for this usage in the United States. This paper discusses the use ...
Using the fundamental equation of constrained motion with inequality constraints

In this paper we investigate a computational approach to keeping a moving particle within a predefined annulus or a predefined bounded space, formed by two concentric spheres with radii L"m"i"n and L"m"a"x, respectively, assuming that said particle cannot maintain a perfectly circular trajectory. The study develops an algorithm for dealing with a system in which constraints are expressed as inequalities. The proposed approach expresses the trajectory in terms of winding/unwinding logarithmic spirals with transitions, expressed as damped vibrations, between them. These transitions are necessary to resolve incompatibility between initial conditions for winding/unwinding spirals. Equations of motion for the particle are obtained by using the Fundamental Equation of Constrained Motion. The obtained simulation results show that such an approach produces the desired pseudo-periodic type of motion, and the particle stays within the predefined region of space for a long duration, although no cycle of its trajectory is repeated.
An algorithm for the classical spatial price equilibrium problem

This paper proposes an algorithm for the solution of the classical Samuelson and Takayama and Judge model of spatial price equilibrium. Computational comparisons on randomly generated numerical examples suggest that this method is substantially more efficient and accurate and, at the same time, requires no more computer storage than an earlier algorithm.
Distribution of resistive body-force in curved free-surface flow

The customary procedure for including resistive effects in turbulent hydraulic and stratified atmospheric flows is to integrate the empirically-known boundary shears over the entire wetted boundary of a thin fluid slab. A resistive body-force is then assumed to exist everywhere in each slab to replace the boundary shearing force. For the classical Saint-Venant (1871) model, this body-force can be shown to have a constant distribution in the vertical direction, and therefore can be evaluated for use in the momentum differential equation. In the newer Dressler theory (1978), however, for unsteady flow over curved beds, it is proved here that a constant body-force distribution is not possible. Its variable distribution is determined as well as its magnitude for use in the curved-flow equations. This variable distribution acts to produce an equal resultant in every thin layer of fluid parallel to the bed in an angular wedge over the curved channel bed. The new curved-flow equations are therefore extended to include resistive effects.
Stoichiometric inhibition of amyloid β-protein aggregation with peptides containing alternating α,α-disubstituted amino acids

We have prepared two peptides based on the hydrophobic core (Lys-Leu-Val-Phe-Phe) of amyloid beta-protein (Abeta) that contain alpha,alpha-disubstituted amino acids at alternating positions, but differ in the positioning of the oligolysine chain (AMY-1, C-terminus; AMY-2, N-terminus). We have studied the effects of AMY-1 and AMY-2 on the aggregation of Abeta and find that, at stoichiometric concentrations, both peptides completely stop Abeta fibril growth. Equimolar mixtures of AMY-1 and Abeta form only globular aggregates as imaged by scanning force microscopy and transmission electron microscopy. These samples show no signs of protofibrillar or fibrillar material even after prolonged periods of time (4.5 months). Also, 10 mol % of AMY-1 prevents Abeta self-assembly for long periods of time; aged samples (4.5 months) show only a few protofibrillar or fibrillar aggregates. Circular dichroism spectroscopy of equimolar mixtures of AMY-1 and Abeta show that the secondary structure of the mixture changes over time and progresses to a predominantly beta-sheet structure, which is consistent with the design of these inhibitors preferring a sheet-like conformation. Changing the position of the charged tail on the peptide, AMY-2 interacts with Abeta differently in that equimolar mixtures form large ( approximately 1 mum) globular aggregates which do not progress to fibrils, but precipitate out of solution. The differences in the aggregation mediated by the two peptides is discussed in terms of a model where the inhibitors act as cosurfactants that interfere with the native ability of Abeta to self-assemble by disrupting hydrophobic interactions either at the C-terminus or N-terminus of Abeta.
Directivity and its energy dependence in solar flare energetic emission

We have studied 72 solar flares simultaneously observed by the Gamma-Ray Spectrometer (GRS, 0.3-1 MeV) and the Hard X-Ray Burst Spectrometer (HXRBS, 30-500 keV) on the Solar Maximum Mission (SMM). Using the spectral analysis results, we studied spectal and size distribution center-to-limb variations for both instruments. The GRS observations show significant center-to-limb variations in both spectral and size distributions, while HXRBS observations show insignificant variations. In general, the GRS spectra are harder than the HXRBS spectra, and their difference increases from center to limb, suggesting that a flattening of the spectrum above 300 keV is inevitable for the gamma-ray emissions. We corrected for the effect of spacecraft pointing and combined HXRBS and GRS data to obtain spectra over the energy range of 0.03-1 MeV. The fluences at various energies were calculated and normalized to the total fluence of the burst to measure the directivity. It is found that the directivity increases with increasing energy, from 1.1 at 50 keV to 6.5 at 1 MeV. These results are consistent with anisotropic electron beams and the physics of Coulomb collision and bremsstrahlung.
The Information Contained in Reconciliations to Earnings Based on US Accounting Principles By Non-US Companies

Abstract To improve comparability of financial statements across countries, the US Securities and Exchange Commission (SEC) requires non-US registrants to either issue financial statements based on US Generally Accepted Accounting Principles (GAAP) or provide in their footnotes a reconciliation of their foreign accounts to their US GAAP counterparts. The New York Stock Exchange has requested the elimination of this requirement on the basis that it serves as a barrier to non-US companies that desire to enter the US market. The SEC maintains that the reconciliations provide important information to investors when assessing the value of a company's stock. This study investigates the information content claim made by the SEC. An event study methodology is utilised that measures the stock price reaction within a short window surrounding the SEC filing date of the firm's 20-F (analogous to the 10-K for US firms). A significantly positive correlation is documented between the stock price reaction and the change ...
Vernier and letter acuities for low-pass filtered moving stimuli

Vernier and letter acuities are both susceptible to degradation by image motion. In a previous study, we showed that the worsening of Vernier acuity for stimuli moving up to 4 degrees/s is accounted for primarily by a shift of visual sensitivity to mechanisms of lower spatial frequency. The purposes of this study were to extend the previous results for Vernier acuity to higher stimulus contrast and velocities, and to determine if a shift in spatial scale can similarly explain the degradation of letter acuity for moving stimuli. We measured Vernier discrimination for a pair of vertical abutting thin lines and letter resolution for a four-orientation letter 'T' as a function of stimulus velocity ranging from 0 to 12 degrees/s. Stimuli were presented at 20 times the detection threshold, determined for each velocity. To determine the spatial-frequency mechanism that mediates each task at each velocity, we measured Vernier and letter acuities with low-pass filtered stimuli (cut-off spatial-frequency: 17.1-1.67 c/deg) and analyzed the data using an equivalent blur analysis. Our results show that the empirically determined, equivalent intrinsic blur associated with both tasks increases as a function of stimulus velocity, suggesting corresponding increases in the size of optimally responding mechanisms. This progressive increase in mechanism size can account for the worsening of Vernier and letter acuities with velocity. Vernier discrimination is found to be more susceptible to degradation by various stimulus parameters than letter resolution, suggesting that different mechanisms are involved in the two tasks. We conclude that the elevations in Vernier and letter acuities for moving stimuli are the consequence of a shift of visual sensitivity toward mechanisms of lower spatial frequencies.
Investigating the surface effects of a tropical cyclone

Understanding how the topmost layer of the ocean behaves during a tropical cyclone can improve forecasting and prediction of cyclone strength and intensity. Previous studies have shown that the degree of sea-air heat transfer within this turbulent layer is an important factor in the overall behavior and propagation of tropical cyclones, but because these effects are difficult to observe directly, data are relatively scarce.
Quantitative analysis of apoptotic and necrotic outer hair cells after exposure to different levels of continuous noise

We have reported that by 2 days after noise exposure the size of cochlear lesion was expanding by outer hair cells (OHCs) dying either by apoptosis or necrosis [Hear. Res. 166 (2002) 62]. The current study was designed to compare the prevalence of the two cell death pathways as a function of time after exposure to noises of different levels. Chinchillas were exposed to a narrow band noise at either 104 or 108 dB SPL for 1 h. At three time points (1, 4 and 30 days) after the noise exposure, the numbers of missing, apoptotic and necrotic OHCs in the cochleas were identified and documented with a combination of TUNEL, caspase-3 and propidium iodide labeling. The subjects exposed to the 108-dB noise showed significantly more apoptotic OHCs than necrotic OHCs in the cochleas examined at days 1 and 4 after the noise exposure. By day 30, apoptotic and necrotic pathologies continued, although in small quantity, with no significant difference in quantity between two types of cell death. The subjects exposed to the 104-dB noise showed a significant difference in the numbers of apoptotic and necrotic OHCs at day 1 after the noise exposure, whereas the difference became statistically insignificant at day 4 and day 30 after the noise exposure. The results of the study indicate that the early expansion of cochlear lesion is attributed primarily to apoptosis, whereas the later stage of lesion expansion is likely the result of an equal contribution from apoptosis and necrosis.