cssi/SciSciGPT-SciSciNet huggingface dataset:
Experimental and Numerical Studies of a Tunable Plasma Antenna Sustained by RF Power

In this work, a custom plasma antenna was created, in which the pressure and gas composition could be varied. The reflection coefficient, deposited power, and the antenna transmission and reception gains were measured for an argon plasma at 0.3 torr sustained by radio frequency power up to 150 W at an excitation frequency of 98 MHz. These measurements were performed through a single RF connector with the help of a directional coupler circuit that isolated the high-power excitation signal from the low-power probing ones. It was found that the resonant frequency of this plasma antenna could be tuned over a span of 80 MHz by varying the applied power in the range of 10–150 W. The antenna gain could also be varied with applied power. At power levels exceeding 40 W, the gain approached, within 3 dB, that of a standard reference antenna. The experimental setup was modeled using ANSYS HFSS software. The simulation and experimental results were found to be in good agreement. This study shows the viability of creating tunable plasma antennas with gain comparable to that of metallic antennas.
Informal mentoring among foster youth entering higher education

Abstract Informal mentoring, anaturally-occurringcaring relationship with a non-parental adult, has been shown to promote positive outcomes for young people, including youth transitioning out of the foster care system. Although we often talk about mentoring as one homogenous experience, recent research has demonstrated there are important variations in who mentors are and what supports they offer. Using survey data provided on youths’ social networks, this study identified 378 informal mentoring relationships provided to 113 former and current foster youth preparing to enter a four-year university. Cluster analysis identified two primary types of mentoring relationships in accordance with previous literature: core and capital mentoring. Following the cluster analysis, type of mentoring relationship was examined across various types of support (instrumental, informational, and emotional support). Findings indicated core mentoring relationships were more predominantly associated with instrumental support, while capital mentoring related more closely with informational support. There were no significant differences between mentoring type and emotional support or youth-rated closeness to mentor. The implications for facilitating socio-emotional support for foster youth are discussed.
Paraneoplastic Dermatoses and Related Conditions

In this chapter, we describe cutaneous presenting signs of internal neoplasms independent of direct tumor, mass, or metastasis effect. Paraneoplastic syndromes occur in upwards of 15% of cancer patients, and skin is the second most commonly targeted organ system. Paraneoplastic dermatoses vary considerably in their prevalence and strength of association with characteristic underlying malignancy. Division of dermatoses suspected as paraneoplastic into obligate (nearly always signaling a neoplasm) and facultative (neoplasms present in a significant minority of cases) provides a useful scaffold for organizing further diagnostic considerations. For those obligate paraneoplastic dermatoses, the onus is on the clinician to exclude without doubt the very characteristic neoplasm. For relatively common dermatoses, recognition of a facultative paraneoplastic process rests on astute observation of atypical onset, distribution, or select associated signs and symptoms.
The practical utility of genetic screening in school settings.

Can genetic screening be used to personalize education for students? Genome-wide association studies (GWAS) screen an individual’s DNA for specific variations in their genome, and how said variations relate to specific traits. The variations can then be assigned a corresponding weight and summed to produce polygenic scores (PGS) for given traits. Though first developed for disease risk, PGS is now used to predict educational achievement. Using a novel simulation method, this paper examines if PGS could advance screening in schools, a goal of personalized education. Results show limited potential benefits for using PGS to personalize education for individual students. However, further analysis shows PGS can be effectively used alongside progress monitoring measures to screen for learning disability risk. Altogether, PGS is not useful in personalizing education for every child but has potential utility when used simultaneously with additional screening tools to help determine which children may struggle academically.
Dysregulation in Sphingolipid Signaling Pathways is Associated With Symptoms and Functional Connectivity of Pain Processing Brain Regions in Provoked Vestibulodynia.

Abstract Provoked vestibulodynia (PVD) is a chronic pain disorder characterized by local hypersensitivity and severe pain with pressure localized to the vulvar vestibule. Despite decades of study, the lack of identified biomarkers has slowed the development of effective therapies. The primary aim of this study was to use metabolomics to identify novel biochemical mechanisms in vagina and blood underlying brain biomarkers and symptoms in PVD, thereby closing this knowledge gap. Using a cross-sectional case-control observational study design, untargeted and unbiased metabolomic profiling of vaginal fluid and plasma was performed in women with PVD compared to healthy controls. In women with PVD, we also obtained assessments of vulvar pain, vestibular and vaginal muscle tenderness, and 24-hour symptom intensity alongside resting-state brain functional connectivity of brain regions involved in pain processing and modulation. Compared to healthy controls, women with PVD demonstrated differences primarily in vaginal (but not plasma) concentrations of metabolites of the sphingolipid signaling pathways, suggesting localized effects in vagina and vulvar vestibule rather than systemic effects. Our findings reveal that dysregulation of sphingolipid metabolism in PVD is associated with increased vulvar pain and muscle tenderness, sexual dysfunction, and decreased functional connectivity strength in pain processing/modulatory brain regions. This data collectively suggests that alterations in sphingolipid signaling pathways are likely an important molecular biomarker in PVD that could lead to new targets for therapeutic intervention. Perspective This manuscript presents the results of a robust, unbiased molecular assessment of plasma and vaginal fluid samples in women with provoked vestibulodynia compared to healthy controls. The findings suggest that alterations in sphingolipid signaling pathways are associated with symptoms and brain biomarkers and may be an important molecular marker that could provide new targets for therapeutic intervention.
The Kobe Bryant Effect: Celebrity Death, Consumer Grief and Product Attachment

In January of 2020, the world lost Kobe Bryant. Kobe was a globally recognized retired professional basketball player. As people mourned the loss of a legend, they began to consume. There was a rush to purchase Kobe Bryant jerseys and sneakers, and every pair of Kobe Bryant shoes sold out (Pesce, 2020). Little is known about underlying consumption motives following the sudden death of a celebrity (Radford & Bloch, 2012), which can impact the consumer market if individuals are looking to purchase memorabilia items. Thus, the purpose of this paper is to develop a conceptual framework that explains consumption motivations resulting from a celebrity death. The framework links the loss of a beloved celebrity manifested through public grief and public desire to "consume" the celebrity as a coping strategy by acquiring celebrity-related products. Group affiliation, memories, pleasure, and centrality as motivators of developing product attachment are mediated by grief.
The Theory of the Firm: Microeconomics with Endogenous Entrepreneurs, Firms, Markets, and Organizations

The Theory of the Firm presents a path-breaking general framework for understanding the economics of the firm. The book addresses why firms exist, how firms are established, and what contributions firms make to the economy. The book presents a new theoretical analysis of the foundations of microeconomics that makes institutions endogenous. Entrepreneurs play a central economic role by establishing firms. In turn, firms create and operate markets and organizations. The book provides innovative models of economic equilibrium that endogenously determine the structure and function of economic institutions. The book proposes an 'intermediation hypothesis' - the establishment of firms depends on the effects of transaction costs and on the extent of the market.
Characterization of a plant-stimulated nuclease from Fusarium solani

Abstract A unique nuclease is released by Fusarium solani f. spp. pisi and phaseoli macroconidia during germination on pea pod endocarp tissue. This Fsp nuclease is produced in greater amounts by macroconidia germinating on pea pods than in Vogel's rich medium or in water. We have characterized the enzymatic activities, and physical properties of this enzyme. Fsp nuclease makes randomly situated single stranded nicks in single- or double-stranded DNA, leaving a 5′ phosphate group and a 3′ hydroxyl group on the nicked DNA strand. This nicking activity is stimulated by divalent cations over a range of 2 10 mM, with Mn 2+ > Ca 2+ > Co 2+ > Mg 2+ . Zinc inhibited the nuclease, even in the presence of stimulatory divalent cations. Fsp nuclease is susceptible to treatment with proteinase K or SDS, indicating a proteinaceous identity, but surprisingly, is resistant to boiling. A 22 kDa molecular weight was estimated by renaturing the enzyme following denaturing electrophoresis. The possible role of this nuclease in virulence is being investigated.
Studies on adenosine triphosphate transphosphorylases. XIII. Kinetic properties of the crystalline rabbit muscle ATP-AMP transphorphorylase (adenylate kinase) and a comparison with the crystalline calf muscle and liver adenylate kinases.

Abstract The steady-state kinetics, at pH 7.4, 25 °C and essentially fixed (Γ/2) of 0.16–0.18, of the rabbit muscle, calf muscle, and calf liver adenylate kinases all seem to be adequately expressed by a random quasi-equilibrium type of mechanism with a rate-limiting step largely at the interconversion of the ternary complexes. However, the data presented, by themselves, will not exclude the possibility of a random mechanism in which product release is rate limiting. In the case of the rabbit muscle enzyme, five substrate pairs for the forward reaction (MgATP 2− /AMP 2− ; MgdATP 2− /dAMP 2− ; MgATP 2− /dAMP 2− ; MgdATP 2− /AMP 2− ; MgϵATP 2− /AMP 2− ) and two substrate pairs for the reverse reaction (MgADP − /ADP 3− ; MgdADP − /DP 3− ) were studied under conditions where a careful and systematic control was exercised over the metal complex nucleotide species. For the forward reactions between MgATP 2− + AMP 2− , and MgdATP 2− + dAMP 2− , the estimated values for K s,1 and K s ,1 (i.e., intrinsic dissociation constants of the substrate from the binary and ternary complexes) differed, pointing to substrate (s) induced conformational changes in the ternary complexes. The fact that similar derived values either for K AMP 2− - and for K AMP 2− could be estimated for each of the above three sets of substrate pairs in the forward reaction, supports the conclusion that a common rate-limiting step exists and is likely in the interconversion of the ternary complexes. ϵAMP 2− was found to be a competitive inhibitor of AMP 2− (at fixed MgATP 2− ) and MgdADP − to be noncompetitive inhibitor of ADP 3− (at fixed MgADP − ), in support of the conclusion of D. G. Rhoads and J. M. Lowenstein ( J. Biol. Chem . (1968) 243 , 3963–3972) that a separate site exists for the magnesium chelates of the nucleotide substrates (MgATP 2− and MgADP − ) and for the uncomplexed nucleotide substrates (ADP 3− and AMP 2− ). Distinguishing kinetic features of the calf liver adenylate kinase over the calf muscle isoenzyme are: 1. (3) inhibition of the liver enzyme by phosphoenolpyruvate; and 2. (4) relatively weak inhibition by P 1 ,P 5 -di-(adenosine-5′) pentaphosphate of the liver enzyme compared to the muscle enzyme (S. A. Kuby et al . (1978) Arch. Biochem. Biophys . 187 , 34–52). A thermodynamic value for K eq = (MgADP − ) (ADP 3− ) ( MgATP 2− ) (AMP 2− ) = 2.7 (±0.6) × 10 −1 has been arrived at, which compared favorably with the average value from its kinetic estimation via four Haldane relations for the three adenylate kinase sets of data.
DC-SIGN activation mediates the differential effects of SAP and CRP on the innate immune system and inhibits fibrosis in mice.

Fibrosis is caused by scar tissue formation in internal organs and is associated with 45% of deaths in the United States. Two closely related human serum proteins, serum amyloid P (SAP) and C-reactive protein (CRP), strongly affect fibrosis. In multiple animal models, and in Phase 1 and Phase 2 clinical trials, SAP affects several aspects of the innate immune system to reduce fibrosis, whereas CRP appears to potentiate fibrosis. However, SAP and CRP bind the same Fcγ receptors (FcγR) with similar affinities, and why SAP and CRP have opposing effects is unknown. Here, we report that SAP but not CRP binds the receptor DC-SIGN (SIGN-R1) to affect the innate immune system, and that FcγR are not necessary for SAP function. A polycyclic aminothiazole DC-SIGN ligand and anti–DC-SIGN antibodies mimic SAP effects in vitro. In mice, the aminothiazole reduces neutrophil accumulation in a model of acute lung inflammation and, at 0.001 mg/kg, alleviates pulmonary fibrosis by increasing levels of the immunosuppressant IL-10. DC-SIGN (SIGN-R1) is present on mouse lung epithelial cells, and SAP and the aminothiazole potentiate IL-10 production from these cells. Our data suggest that SAP activates DC-SIGN to regulate the innate immune system differently from CRP, and that DC-SIGN is a target for antifibrotics.
The Enzymatic Reduction of Retinal to Retinol in Rat Intestine

Abstract The reduction of retinal to retinol was examined with enzyme preparations from homogenates of rat intestinal mucosa. Retinal reduction was catalyzed by a soluble mucosal enzyme which was purified 13-fold by ammonium sulfate precipitation, column chromatography, and heating (55° for 6 min). The enzyme was relatively heat-stable and had a molecular weight approximately in the range of 60,000 to 80,000. The partly purified reductase was unable to oxidize ethanol in the presence of NAD+. Retinal reduction required NADH or NADPH as cofactor. Both reduced nucleotides were effective; at low nucleotide concentration NADH was more effective, whereas at high concentrations the reaction rate was slightly greater with NADPH. The reaction was stimulated by the addition of glutathione and was inhibited by —SH inhibitors. No other cofactors were required. There was a sharp pH optimum near 6.3. Retinal reduction displayed typical Michaelis kinetics, with a Vmax of 2 x 10-6 moles of retinal formed per hour per mg of protein and with an apparent Km of 2 x 10-5 m. The enzyme appears to be a relatively nonspecific aldehyde reductase. Short and medium chain aliphatic aldehydes, of length C-2 to C-14, were actively reduced, with greatest activity being seen with aldehydes of length C-4 to C-8. Unsaturated C-18 fatty aldehydes were reduced at a lesser rate, but saturated aldehydes of length C-16 or greater were not reduced. The enzyme was stereospecific for 4R-NADH-4-3H1, and did not incorporate tritium from 4S-NADH-4-3H1 into the product retinol.
Effect of cadmium on fungi and on interactions between fungi and bacteria in soil: influence of clay minerals and pH.

Fungi (Rhizopus stolonifer, Trichoderma viride, Fusarium oxysporum f. sp. conglutinans, Cunninghamella echinulata, and several species of Aspergillus and Penicillium) tolerated higher concentrations of cadmium (Cd) when grown in soil than when grown on laboratory media, indicating that soil mitigated the toxic effects of Cd. In soil amended with clay minerals, montmorillonite provided partial or total protection against fungistatic effects of Cd, whereas additions of kaolinite provided little or no protection. Growth rates of Aspergillus niger were inhibited to a greater extent by 100 or 250 mug of Cd per g in soil adjusted to pH 7.2 than in the same soil at its natural pH of 5.1. However, there were no differences in the growth rates of Aspergillus fischeri with 100 or 250 mug of Cd per g in the same soil, whether at pH 5.1 or adjusted to pH 7.2. Growth of A. niger and A. fischeri in a soil contaminated with a low concentration of Cd (i.e., 28 mug/g), obtained from a site near a Japanese smelter, did not differ significantly from growth in a soil collected some distance away and containing 4 mug of Cd per g. Growth of A. niger in sterile soil amended with 100 mug of Cd per g and inoculated with Bacillus cereus or Agrobacterium tumefaciens was reduced to a greater extent than in the same soil containing 100 mug of Cd per g but no bacteria. The inhibitory effects of Agrobacterium radiobacter to A. niger were slightly reduced in the presence of 100 mug of Cd per g, whereas the inhibitory effects of Serratia marcescens were enhanced.
Coupling groundwater and land surface processes: Idealized simulations to identify effects of terrain and subsurface heterogeneity on land surface energy fluxes

[1] This work investigates the role of terrain and subsurface heterogeneity on the interactions between groundwater dynamics and land surface energy fluxes using idealized simulations. A three-dimensional variably saturated groundwater code (ParFlow) coupled to a land surface model (Common Land Model) is used to account for both vertical and lateral water and pressure movement. This creates a fully integrated approach, coupling overland and subsurface flow while having an explicit representation of the water table and all land surface processes forced by atmospheric data. Because the water table is explicitly represented in these simulations, regions with stronger interaction between water table depth and the land surface energy balance (known as critical zones) can be identified. This study uses simple terrain and geologic configurations to demonstrate the importance of lateral surface and subsurface flows in determining land surface heat and moisture fluxes. Strong correlations are found between the land surface fluxes and water table depth across all cases, including terrain shape, subsurface heterogeneity, vegetation type, and climatological region. Results show that different land forms and subsurface heterogeneities produce very different water table dynamics and land surface flux responses to atmospheric forcing. Subsurface formation and properties have the greatest effect on the coupling between the water table and surface heat and moisture fluxes. Changes in landform and land surface slope also have an effect on these interactions by influencing the fraction of rainfall contributing to overland flow versus infiltration. This directly affects the extent of the critical zone with highest coupling strength along the hillside. Vegetative land cover, as seen in these simulations, has a large effect on the energy balance at the land surface but a small effect on streamflow and water table dynamics and thus a limited impact on the land surface-subsurface interactions. Although climate forcing has a direct effect on water table dynamics and feedbacks to the land surface, in this study it does not overcome that of subsurface heterogeneity and terrain.
Characterization and simulation of the gas pressures in space for high voltage breakdown

The theory of gas flow in the molecular range was used to develop equations that may be used to model the pressures in a space system. It is noted that one key factor associated with the volume electrical breakdown in a vacuum is the residual gas in the vacuum. In a space system it is possible that regions could have pressures that are close to the Paschen minimum. The pressures of evacuated regions are determined mainly by the pressures of connected regions, the conductances to the connected regions, and the outgassing load presented by the materials in the regions. In the molecular flow range, conductances are modeled by C=1.6*10/sup 5/ A alpha where A is the area of the orifice connecting two regions and alpha is the transmission probability of the connection. The outgassing load presented by the materials is modeled by integrating the number of molecules leaving the surface. The pressure change may then be calculated using dP/dt=(-CP+Q)/V. These techniques have been incorporated into a computer model used to predict the pressures in vacuum regions. The results of an application of this model are presented. >
Cardioprotective Effects of Dietary Polyphenols

Dietary polyphenols have been shown to possess cardioprotective effects. For example, the most noted role of grape polyphenols is in the French Paradox, in which a diet high in saturated fat accompanied by regular consumption of red wine is associated with a low risk of coronary heart disease (CHD). Initially, the paradox was thought to be driven by the postulated major action of grape polyphenols in inhibiting LDL oxidation. Although many studies have shown inhibitory effects of polyphenols on LDL oxidation, there have been an equal number of studies that showed a null effect on this variable. Although there are contrasting viewpoints on the effects of polyphenols on LDL oxidation variables, there is increasing evidence that these compounds possess additional cardioprotective functions including altering hepatic cholesterol absorption, triglyceride assembly and secretion, the processing of lipoproteins in plasma, and inflammation. It is the purpose of this review to examine recent information on the multiple functions of dietary polyphenols, with an emphasis on grape polyphenols, in decreasing the risk of CHD by improving plasma lipid profiles and reducing inflammation.
Shallow Trench Isolated Buried N+ FAMOS Transistors for VLSI EPROMs

This paper presents a novel application of shallow trench isolation (less than one micron deep) to buried N+ FAMOS (Floating gate Avalanche Injection MOS) transistors with applications to VLSI EPROMs, The trench isolation has improved not only bitline isolation but also the programming efficiency of an equally novel cross-point Advanced Contactless EPROM (ACE) cell.[1]
Wave-function equations for photons and electrons

The wave equations for photons and electrons are presented. The wave functions must include positrons as particles as well as electrons and photons. These differential equations are shown to be equivalent to the unrenormalized perturbation series generated by Feynman rules. The procedure for replacing the bare mass and charge by the experimental values (renormalization) is illustrated for the case of the dressed electron. The introduction of atomic nuclei is discussed.
Hyperparathyroidism-jaw tumor syndrome: Results of operative management

Background Hyperparathyroidism-jaw tumor syndrome (HPT-JT) is a rare autosomal dominant disease secondary to germline inactivating mutations of the tumor suppressor gene HRPT2/CDC73. The aim of the present study is to determine the optimal surgical approach to parathyroid disease in patients with HPT-JT.
Effect of sitting or standing on touch screen performance and touch characteristics.

Objective:The aim of this study was to evaluate the effect of sitting and standing on performance and touch characteristics during a digit entry touch screen task in individuals with and without mo...
Plasmid reference center registry of transposon (Tn) allocations through July 1981

The criteria for transposable genetic elements (Cohen, 1976) were stated at the Cold Spring Harbor meeting in 1976 (Campbell et al., 1977) and defined and clarified further (Campbell et al., 1979). At that meeting the Plasmid Reference Center agreed to serve as a clearing house for continuous transposon registry. Interim lists have been previously published (Lederberg, 1978, 1980, Microbial Genetics Bulletin 44 : 31; ibid 48 : 90). A complete file of Tn elements is listed below.
What you don't know can hurt you: The effects of performance criteria ambiguity on sex differences in self-confidence1

Previous investigators have suggested that women display lower self-confidence than men across almost all achievement situations. The empirical validity of this suggestion is assessed in an experiment testing the hypothesis that performance evaluation guidelines moderate sex difference in self-confidence. Undergraduates read the guidelines by which their performance on an impending test would be evaluated. Guidelines were: ambiguous (A); clear—specifying the dimensions of performance to be examined, but not providing any examples of others' performance against which subjects' work would be compared (C); or clear with performance examples (CE). Subjects then completed the test and estimated how will they had done. Results showed the predicted pattern in conditions A and C: While women underestimated their actual performance much more than men when guidelines were ambiguous, they did not do so when guidelines were clear. Further, the rise in self-confidence for women from conditions A to C was greater than that for men. Also as predicted, both sexes' self-confidence and performance were higher in condition C than in condition A. Finally, although condition CE was expected to depress only women's self-confidence and performance, both sexes showed this effect. It is concluded that sex differences in self-confidence are moderated by situation variables and that programs designed to reduce such differences might be improved by a greater focus upon women's response to clearly specifiable factors in achievement settings.
5-Fluoro-2'-deoxycytidine 5'-monophosphate is a mechanism-based inhibitor of thymidylate synthase.

Abstract Thymidylate synthase (TS) is inhibited by 5-fluoro-2′-deoxycytidine 5′-monophosphate (FdCMP). From initial velocity measurements, the apparent K i for the binary FdCMP-enzyme complex was about 20 μM. In the presence of 5,10-methylene-5,6,7,8-tetrahydrofolate (CH 2 H 4 folate), FdCMP causes a time-dependent inactivation of the enzyme and formation of a TS-FdCMP-CH 2 H 4 folate complex. The ternary complex contains one mol of inhibitor per monomer of enzyme, and can be readily isolated on nitrocellulose filters. Dissociation of the ternary complex is quite slow ( t l 2 ≈ 16 h ), and yields unchanged FdCMP. As with the corresponding complex formed with 5-fluoro-2′-deoxyuridine 5′-monophosphate (FdUMP), the TS-FdCMP-CH 2 H 4 folate complex shows a differential absorbance maximum at 326 nm, and is stable to SDS-PAGE. Taken together, these results indicated that FdCMP is a slow, tight binding inhibitor of TS and has a mechanism of inhibition similar to that of FdUMP.
Probabilistic Coalition Structure Theories An Empirical Comparison in Four-Person Superadditive Sidepayment Games

This article reports a comparative test of the central-union theory in four-person sidepayment games. Predictions by two variants of central-union theory (CU-1 and CU-2) are tested vis-a-vis predictions by three other solutions (the equal excess model, the Myerson-Shapley solution, and the kernel). With respect to players' payoffs, results show that CU-1, CU-2, equal excess, and Myerson-Shapley models have essentially equal predictive accuracy and that all of these are superior to the kernel in the test games. However, when coalition structure probability predictions are incorporated in the test, both CU-1 and CU-2 emerge as more accurate than all the other models tested.
Environmental factors associated with a toxic bloom of Microcystis aeruginosa

Environmental factors associated with the occurrence of toxic cyanobacterial blooms and toxin production were investigated during the summers of 1994 and 1995 in Steilacoom Lake, Washington. A pron...
iMap: a stable layout for navigating large image collections with embedded search

Effective techniques for organizing and visualizing large image collections are in growing demand as visual search gets increasingly popular. Targeting an online astronomy archive with thousands of images, we present our solution for image search and clustering based on the evaluation image similarity using both visual and textual information. To lay out images, we introduce iMap, a treemap-based representation for visualizing and navigating image search and clustering results. iMap not only makes effective use of available display area to arrange images but also maintains stable update when images are inserted or removed during the query. We also develop an embedded visualization that integrates image tags for in-place search refinement. We show the effectiveness of our approach by demonstrating experimental results and conducting a comparative user study.
SPECTROSCOPY AND LUMINESCENCE PROPERTIES OF CdF$sub 2$:Eu

Characteristics relevant to the application of Cd${\mathrm{F}}_{2}$: ${\mathrm{Eu}}^{+3}$ to optical maser use were investigated. The line fluorescence was analyzed to obtain the positions of the lowest energy europium crystal states and these were found to be consistent with the europium ion being in a crystal field having essentially tetragonal symmetry. The strongest emission line, at 5893.1 A, contains $\frac{1}{10}$ of the total fluorescence and is due to a transition between states at 17278.6 ${\mathrm{cm}}^{\ensuremath{-}1}$ and 309.7 ${\mathrm{cm}}^{\ensuremath{-}1}$. At 15\ifmmode^\circ\else\textdegree\fi{}K its width at half intensity is 0.32 ${\mathrm{cm}}^{\ensuremath{-}1}$. It was found that the europium fluorescence could be sensitized by the addition of sulfide to the crystals and the total fluorescent quantum efficiency was determined to be 0.8\ifmmode\pm\else\textpm\fi{}0.2. The threshold power for oscillations in a rod of 0.1 ${\mathrm{cm}}^{2}$ cross-sectional area was calculated to be 18 watts.
Diffraction of light by two spatially separated parallel ultrasonic waves of different frequency

A theory is developed for the diffraction of light by two spatially separated parallel ultrasonic progressive waves of different frequency. The preliminary theories ofRaman andNath [C. V.Raman and N. S.Nath, Proc. Indian Acad. Sci. A2, 406–412; 413–420 (1935)] for normal and oblique incidence are taken to be valid. The resulting equations are extensions of earlier results of R.Mertens, Z. Physik160, 291–296 (1960). The predicted periodicity of the diffraction spectrum with increasing sound beam separation agrees with the well known periodicity of the light intensity distributions in the Fresnel zone of the phase grating formed by the first ultrasonic wave. Results of numerical calculations are presented to illustrate features of the theoretical results, as reflected in the first order of diffraction for 3.0 and 6.0 Mc ultrasonic waves in water.
Acute effects of THC on time perception in frequent and infrequent cannabis users

Rationale Cannabinoids have been shown to alter time perception, but existing literature has several limitations. Few studies have included both time estimation and production tasks, few control for subvocal counting, most had small sample sizes, some did not record subjects’ cannabis use, many tested only one dose, and used either oral or inhaled administration of Δ9-tetrahydrocannabinol (THC), leading to variable pharmacokinetics, and some used whole-plant cannabis containing cannabinoids other than THC. Our study attempted to address these limitations.
Spline Estimation of Paths Using Bearings-Only Tracking Data

Abstract In many applications, bearings are measured to a moving object with the goal of estimating the object's course of movement. If movement is appropriately modeled as a smooth deterministic curve in the plane, then a cubic spline is a reasonable representation of the curve. Maximum likelihood estimators are presented for parameters of regression splines, assuming that observation errors follow a Von Mises distribution. Location estimates are obtainable even when data are sparse. Path estimation error, number and placement of knots, and outlier detection are discussed. Examples, including both simulated paths and observations from a wildlife radio-tracking study, are presented.
Homeowner Warranties: A Study of the Need and Demand for Protection Against Unanticipated Repair Expenses

The decision to purchase a home often is made without complete information concerning the structural soundness of the dwelling or the condition of its mechanical systems. This paper presents detailed information on the nature and magnitude of unanticipated home repair costs on the basis of data obtained from a HUD-sponsored survey of some 1800 households that purchased existing homes two years prior to the survey. The potential market demand for home inspection and warranty programs is estimated on the basis of data obtained from a second survey of approximately 1800 recent home purchasers. Finally, the economic feasibility of two potential government warranty programs is examined and a number of tentative policy conclusions are drawn.
Depression In The Workplace: Effects On Short-Term Disability

We analyzed data from two national surveys to estimate the short-term work disability associated with thirty-day major depression. Depressed workers were found to have between 1.5 and 3.2 more short-term work-disability days in a thirty-day period than other workers had, with a salary-equivalent productivity loss averaging between $182 and $395. These workplace costs are nearly as large as the direct costs of successful depression treatment, which suggests that encouraging depressed workers to obtain treatment might be cost-effective for some employers.
Two Types of Value-Affirmation: Implications for Self-Control Following Social Exclusion

The authors tested the hypothesis that affirming self-transcendent values attenuates negative consequences of self-threat better than affirming self-enhancement values. If value-affirmation buffers...
Characteristics of gasoline in-cylinder direct injection engine

Abstract Combustion characteristics of a gasoline direct-injection (DI) engine were studied with fuel injection timing varied. This study showed that emissions at part load are reduced by optimizing in-cylinder air motion and injection timing. Antiknock quality and volumetric efficiency are improved at high loads. With our DI system fuel does not stick on the intake port wall during engine warmup and transient mode, and thus even a cold engine can be controlled with a quick response and a high resolution, which, as a result, can reduce emissions. Also, lean limit is significantly improved by optimizing the injection timing.
Bone mineral density in adolescent and young adult women on injectable or oral contraception.

Purpose of review: This report critically reviews recent original research articles that pertain to bone mineral density in young adult women utilizing injectable depot medroxyprogesterone acetate or oral contraceptives. Recent findings: Some evidence indicates that depot medroxyprogesterone acetate and ultra-low dose oral contraceptives (containing 20 mg ethinyl estradiol) may interfere with the large increases normally observed in adolescence; however the same degree of bone loss (or lack of bone gain) associated with these drugs is not so impressive in young adult women who would typically be experiencing small changes in bone mass. Data obtained from young adult women show that low dose (30–40 mg ethinyl estradiol) oral contraceptives seem to be more protective of bone than ultra-low dose oral contraceptives. The few extant data suggest that there may be substantial increases in bone mass after discontinuation of depot medroxyprogesterone acetate; no information is available regarding the response of bone after discontinuation of oral contraceptives. As the clinical risk for fracture is usually several decades later several exogenous factors such as diet and exercise may exert overriding influences on later bone health. Moreover without contraception the clinical outcome may be unwanted pregnancy and its potential impact on bone health. Summary: Recent findings suggest that depot medroxyprogesterone acetate and ultra-low dose oral contraceptives may interfere with achieving optimal peak bone mass in very young women; however there may be substantial recovery after cessation of these methods and overriding long-term influences on bone health imposed by a myriad of lifestyle factors. (authors)
Further implications of potential models of composite particles having highly relativistic components

Abstract Refining previously proposed potential models of electrons, we find that a potential energy term in the relativistic Schrodinger equation may be associated with energy of field quanta and that the fine-structure constant may be associated with the inverse of a Lorentz scale factor. Harmonic quarks and a 20.4 eV/ c 2 composite are rather natural consequences of these models.
Sensor array for PV shading measurements

The number of photovoltaic (PV) system installations around the world is rapidly expanding, driven by a combination of factors including steadily falling costs, tax and rebate incentives, and interest in carbon reduction. Optimizing the total energy production of PV systems is dependent on minimizing losses and avoiding conditions which can adversely affect performance and lifetime. Module shading is one such critical element. Shading can arise from inter-row effects as well as from vegetation, buildings, and precipitation. In order to make objective measurements of shading, we have designed a system employing spot metering and sensor arrays. In order to bring array monitoring costs to affordable levels, we have employed low-cost photodiodes that are deployed in the mobile and computer market. Our shading sensor is organized in a linear array. This paper describes the development and characterization of the sensor array and provides examples of its use to evaluate the effects of inter-row shading that could be experienced by a typical PV module.
Psychosocial status predicts mortality in patients with life-threatening ventricular arrhythmias

Background Quality-of-life (QoL) instruments evaluate various aspects of physical, mental, and emotional health, but how these psychosocial characteristics impact long-term outcome after cardiac arrest and ventricular tachycardia (VT) is unknown. Objective The purpose of this study was to evaluate the relationship of baseline QoL scores with long-term survival of patients enrolled in the Antiarrhythmics Versus Implantable Defibrillators (AVID) trial. Methods Formal QoL measures included SF-36 mental and physical components, Patient Concerns Checklist, and Ferrans and Powers Quality-of-Life Index–Cardiac Version. Multivariate Cox regression was used to assess the association of survival and these measures, adjusting for index arrhythmia type, gender, race, age, ejection fraction, history of congestive heart failure, antiarrhythmic therapy, and beta-blocker use. Results During mean follow-up of 546 ± 356 days, 129 deaths occurred among 740 patients. Higher baseline SF-36 physical summary scores ( P P = .015), and lower baseline Patient Concerns Checklist summary scores ( P = .047) were associated with longer survival, even after adjustment for clinical variables. When QoL measures were examined simultaneously, only the SF-36 physical summary score remained significant ( P = .002). Conclusion During recovery after sustained VT or cardiac arrest, formal baseline QoL assessment provides important prognostic information independent of traditional clinical data.
Problems and Prospects of Meeting the Basic Energy Needs of Rural Communities in Developing Countries Through the Utilization of Wind and Solar Energy Systems

The problems and prospects of solar and wind energy technologies for rural energy supply in developing countries are examined, followed by an overview of key attributes of these technologies. The application of wind and solar systems for cooking, water pumping, drying, water heating, and electric power supply are reviewed. Two detailed case studies are given, the first discussing the potential of solar and wind systems for rural water pumping in Morocco, and the second, examining the “wind farms” producing electric power in California and the potential for their use in developing countries.
Spontaneous breakdown and hadronic symmetries

Using the ideas of Higgs and Weinberg about spontaneous symmetry breakdown, we construct possibly renormalizable models of low-spin hadrons, including massive non-Abelian vector mesons. An intriguing new view of hadron symmetries and symmetry breaking emerges.
Cumulate Xenolith in Oahu, Hawaii: Implications for Deep Magma Chambers and Hawaiian Volcanism

The maximum depth at which large (>1000 km3) terrestrial mafic magma chambers can form has generally been thought to be the Moho, which occurs at a mean depth of about 35 kilometers beneath the continents and 8 kilometers beneath ocean basins. However, the presence of layers of cumulus magnesium-rich spinel and olivine and intercumulus garnet in an unusual mantle xenolith from Oahu, Hawaii, suggests that this rock is a fragment of a large magma chamber that formed at a depth of about 90 kilometers; Hawaiian shield-building magmas may pond and fractionate in such magma chambers before continuing their ascent. This depth is at or near the base of the 90-million-year-old lithosphere beneath Oahu; thus, rejuvenated stage alkalic magmas containing mantle xenoliths evidently also originate below the lithosphere.
Still on hold? A retrospective analysis of competitive implications of the Telecommunication Act of 1996, on its 10th year anniversary

Abstract This study provides a retrospective analysis exploring competition in the US telecommunication industry, a decade after passage of the highly deregulatory Telecommunications Act of 1996. Using history as a guide, it reviews recent merger activity facilitated by the Act, profiles the present state of concentration in cable and telephony and explores prospects for cross-media competition permitted by the Act. Study results suggest that industry concentration in these telecommunication industries has increased dramatically since the mid-1990s, with the top four firms controlling over 60% of the market in each industry. The stand-alone long distance industry has been virtually eliminated by the acquisitions of AT&T and MCI by Regional Bell Operating companies, whose extensive lobbying efforts and lawsuits, challenging service restrictions under the Act and their enforcement, play to RBOC advantages in scale and local loop control. Despite prospects for competition stemming from Internet and wireless alternatives, recent consolidation has been accompanied by hyper-inflationary rate increases in both industries. Recent developments, including AT&T's acquisition by former Baby Bell progeny SBC and its earlier sale of AT&T cable assets to Comcast, may thus signal a new era of competitive “detente” among telecommunication providers. Implications for cross-industry competition between cable and telephone industries for broadband, cable and voice services are explored.
An abnormal C-groupchromosome in a child with severe growth retardation

Summary A 16-month-old infant girl with a largemetacentric chromosome replacing an autosome of the C-group (6–12) in association with multiple anomalies, severe mental retardation, and growth failure is reported. The patient was shown to have a deficient human growth hormone response to hypoglycemia.
Orthostatic tremor: Clinical and electrophysiologic characteristics

Orthostatic tremor, sometimes known as "shaky legs syndrome," is a disorder of middle-aged or elderly people characterized by feelings of unsteadiness in the legs and a fear of falling when standing. Patients stand on a wide base but walk normally. These symptoms are due to high-frequency (13-18 Hz) burst firing in weight-bearing muscles. They are attenuated by walking and are abolished immediately by sitting. Some authors believe that the disorder is a variant of essential tremor. This study reports the clinical and electrophysiologic features of orthostatic tremor in 30 patients. The findings indicate that orthostatic tremor is distinct from essential tremor, both clinically and electrophysiologically. The major differences are the frequency of electromyographic burst firing, the invariable involvement of lower limb and paraspinal muscles, and the task-specific nature of the tremor in orthostatic tremor. The study shows that the diagnosis can be established rapidly with surface electromyographic recordings.
Mechanism for superior subluxation of the glenohumeral joint in fibrodysplasia ossificans progressiva

Progressive heterotopic ossification leads to ankylosis of the major joints in patients who have fibrodysplasia ossificans progressiva. Joint subluxation has not been recognized widely in patients with this disease. The clinical records and radiographs of 79 patients with fibrodysplasia ossificans progressiva were reviewed and, it was found that humeral to chest wall synostosis and subluxation of the glenohumeral joint had occurred in 21% of skeletally immature patients and in 74% of skeletally mature patients. In fibrodysplasia ossificans progressiva, synostosis of the humeral shaft to the chest wall commonly occurs by 7 years of age, well before the age of proximal physeal closure. The continued growth of the proximal humeral physis in the presence of a humeral to chest wall synostosis causes the humeral head to migrate superiorly, thus promoting growth related subluxation. The clinical significance of this finding for patients who have fibrodysplasia ossificans progressiva is unknown, but this unique model will be useful in the study of shoulder biomechanics and growth plate physiology.
Precision passive ranging

Abstract The problem of passive ranging is complex, yet important. This paper formulates it as a nonlinear least squares problem which is solved via the Newton-Raphson technique. We use the FEED method for rapid prototyping and the automatic evaluation of partial derivatives. The paper presents two significant results. 1. The approach leads to rapidly convergent and accurate estimates of position for a variety of different noise models. 2. The use of FEED has led to a new and exact solution to the question of evaluating the effect of noise on parameter estimates without the need to perform Monte Carlo computational experiments. Nonlinear methods such as this require preliminary parameter estimates, for which we suggest associative memory neural networks.
Acoustics: Subtleties of the sonic

Douglas Repetto explores the multilayered aesthetic of sound as art at New York's Museum of Modern Art.
Variations of the arterial anatomy of the foot

Reconstruction of the arteries of the foot in patients with severe chronic arterial occlusive disease has become a routine and valuable procedure. However, it is frequently difficult to select the optimal site for the distal arterial anastomosis. In order to determine the most important anatomic variations of foot arteries and the relationship of the dorsalis pedis artery to crossing tendons, the following study was performed in 30 cadaver limbs of 17 persons (9 men and 8 women). Their mean age at death was 69.8 years (range: 42 to 93 years). Methods to evaluate anatomy included anatomic dissection, arteriography, and preparation of corrosion cast models. The latter was performed by injection of liquid plastic and catalyst into the tibial arteries followed by chemical debridement of the soft tissue of the foot. Photographs of the corrosion cast models were taken at various stages of soft tissue dissolution. The dorsalis pedis artery was absent in 6.7% of the cases, and the arcuate artery was absent in 33%. The dorsalis pedis artery arose from the peroneal artery in 6.7%. The dorsalis pedis artery crossed under the extensor hallucis longus tendon at the ankle in 54%, above the ankle in 43%, but below the ankle in only 3%. Our study suggests that the optimal site for the dorsalis pedis artery anastomosis on the foot is the segment distal to the ankle.