cssi/SciSciGPT-SciSciNet huggingface dataset:
Further characterization of the pituitary-adrenocortical responses to stress in Chiroptera.

Previous studies on bats from this laboratory have revealed the presence of exceptionally high circulating levels of glucocorticoids in two species of the sub-order Megachiroptera. In the present study, the following questions were asked: (1) what effect does the routine handling and examination of captive bats have on the activity of their hypothalamic-pituitary-adrenocortical (HPA) axis?; (2) are the unusually high plasma levels of cortisol and corticosterone found in Pteropus hypomelanus associated with high levels of circulating adrenocorticotropic hormone (ACTH)?; (3) are there diurnal changes in stress responsivity in this species?; and (4) how do levels of glucocorticoids in P. hypomelanus compare with those found in other species of Chiroptera (both micro and megachiropteran species)? Of five species examined, P. hypomelanus had slightly higher total glucocorticoid levels than P. pumulis, but ∼-fold higher levels than in three species of Microchiroptera (Artibeus jamaicensis, Carollia perspicillata, and Myotis lucifigus). There was a pronounced diurnal rhythm in glucocorticoid levels in one species (M. lucifigus) for which this was determined. A 1-h period of restraint stress increased glucose and glucocorticoid levels in P. pumulis, and also increased ACTH and glucocorticoids in P. hypomelanus. Fifteen minutes of routine handling (weighing, measuring, etc.) elicited a significant rise in plasma glucocorticoids in P. hypomelanus to combined peak (cortisol plus corticosterone) levels of over 1,000 ng/ml (100 μg%). There was no significant difference in the response to handling in bats tested in the morning or evening. Basal ACTH levels as detected by radioimmunoassay were low in P. hypomelanus, in spite of high steroid levels. Displacement of labeled ACTH by plasma of P. hypomelanus was roughly parallel to that produced by synthetic human ACTH. The identity of immunoreactive ACTH was confirmed by subjecting separate aliquots of plasma to an immunoradiometric assay (IRMA), which operates on a different principle from the RIA and necessitates an intact molecule closely resembling human ACTH. We conclude that bats possess a “stress response” similar in some ways to that seen in other mammals. The extremely high constitutive and stress-induced levels of glucocorticoids in the Megachiroptera are nearly unique among mammals. Although high circulating levels of ACTH were detected by IRMA, but not by RIA, it is possible that the Chiropteran adrenal gland is hypersensitive to ACTH or possesses exceptionally active intracellular steroidogenic mechanisms. Finally, the routine daily procedures associated with measuring, weighing, and monitoring bats in captivity constitutes a significant stress to the animal as revealed by pronounced activation of the HPA axis. © 1994 Wiley-Liss, Inc.
Studies of childhood brain tumors using immunohistochemistry and microwave technology: methodological considerations

The immunohistochemical detection of antigens in archival tissue sections has been hampered by the poor reactivity of certain polypeptides in conventional formalin-fixed, paraffin-embedded material. For example, the poor reactivity of neurofilament proteins (NFPs) in surgical and autopsy specimens has been a major drawback of previous large, retrospective, clinicopathologic studies of pediatric primitive neuroectodermal tumors (PNETs), also known as medulloblastomas. We report our experience with a method of antigen retrieval which greatly enhanced the immunohistochemical detection of neuronal and glial intermediate filament proteins, retinal S-antigen (RSA), and the proliferating cell nuclear antigen (PCNA) in archival, paraffin-embedded, formalin or Bouin's-fixed, pediatric brain tumors, particularly PNETs. The technique involves adding a single brief step to an established avidin-biotin complex (ABC) immunohistochemical protocol (Vectastain Elite Kit). This step involves boiling tissue sections in distilled water for 5 min in a microwave oven. The specificity of staining was consistent with known cell and tissue specificities of the well-characterized monoclonal antibodies used and there was minimal background. Synaptophysin (SYN) staining was unaffected by heating and immunoreactivity of the low affinity nerve growth factor (p75NGFR) and the neural cell adhesion molecule (NCAM) were lost. The enhanced detection of neuronal and glial antigens in routinely prepared, formalin-fixed, archival material should facilitate large retrospective clinicopathologic studies designed to assess the prognostic implications of differentiation in PNETs and to better understand the biology of these tumors.
Potential role of nuclei in cloud element formation at high altitudes

Abstract The role of aerosols in providing a heterogeneous nucleation contribution to cirrus cloud ice crystal formation has long been an unresolved question. A mobile aerosol sampling facility was employed on the NCAR Sabreliner research aircraft to take aerosol samples from the vicinity of cirrus clouds over Colorado and Wyoming. Tandem electrostatic classifier and impactor technique were used to measure aerosol size distribution, hydration capability and composition information. The results suggest that aerosol related heterogeneous nucleation processes are active in cirrus cloud processes.
Attitudes Toward Nuclear Weapons and Nuclear War: 1945–1982

This paper examines responses to nuclear-related survey items from 1945 through April, 1982, which are on file at the Roper Center for Public Opinion Research. A content analysis of the wordings of the 498 items identified a number of themes which have appeared in many items across time. These include questions about criteria for the production and use of nuclear weapons, perceptions of the nuclear arms race, and personal fears and apprehensions. Analysis of response data for a sample of the items revealed a modest increase in personal fears across time, and a sharper increase in disenchantment with both the arms race and U.S. readiness to use nuclear weapons in response to Soviet invasion of Western Europe. These trends are tentatively explained in terms of altered perceptions of the strategic balance, with the Russians now seen as having reached or even exceeded parity with the U.S. An agenda is suggested for increasing our understanding of nuclear-related public opinion in the future.
Tuberculosis Control Policies in Major Metropolitan Health Departments in the United States: V. Standard of Practice in 1992

Since 1978, we have surveyed the 28 metropolitan health departments initially reporting > 250 cases of tuberculosis/yr to determine the standard of practice in the control of pulmonary tuberculosis and the factors affecting treatment policy. In this survey, results were compared with data obtained in 1978, 1980, 1984, and 1988. As in the previous years, all departments completed the survey. The predominant treatment regimen was 6 months of chemotherapy (64 ± 1.33% of patients) involving isoniazid (I), rifampin (R), and pyrazinamide (Z). Estimated duration of treatment, which had decreased from 20.2 ± 2.1 months in 1980 to 7.58 ± 1.02 months in 1988, increased to 9.34 ± 2.32 months in 1992 (p < 0.01). This was attributed to an increase in drug-resistant cases (17 of 25 programs) and to increased incidence of HIV infection during the previous 4 yr. In 1984, HIV infection was estimated to coincide with tuberculosis in 2.54% of all patients, 7.72% in 1988, and 17.42% in 1992. Several other major departures fr...
Computational simulation to understand vision changes during prolonged weightlessness

A mathematical model of whole body and cerebral hemodynamics is a useful tool for investigating visual impairment and intracranial pressure (VIIP), a recently described condition associated with space flight. VIIP involves loss of visual acuity, anatomical changes to the eye, and, usually, elevated cerebrospinal fluid pressure. Loss of visual acuity is a significant threat to astronaut health and performance. It is therefore important to understand the pathogenesis of VIIP. Some of the experimental measurements that could lead to better understanding of the pathophysiology are impossible or infeasible on orbit. A computational implementation of a mathematical model of hypothetical pathophysiological processes is therefore valuable. Such a model is developed, and is used to investigate how changes in vascular compliance or pressure can influence intraocular or intracranial pressure.
Physiological and Behavioral Engagement in Social Contexts as Predictors of Adolescent Depressive Symptoms

Depressive symptoms are considered to have evolutionary social functions to reduce social risks with peers and family members. However, social processes and their relationship to depressive symptoms have been understudied in adolescent boys. Low engagement in social contexts may predict depressive symptoms in adolescent boys, as it may signify efforts to reduce social risks. To address these issues, this study focused on 160 boys at risk for affective problems based on low socioeconomic status. We evaluated how behavioral and physiological engagement in peer and family contexts, respectively, in late childhood predicted depressive symptoms at age 12 and age 15. Social withdrawal was measured across late childhood (ages 9–12) in a camp setting using a latent variable of teacher ratings of withdrawn behavior, peer nominations of withdrawn behavior, and camp counselor ratings of withdrawn behavior. Physiological reactivity was measured during a provocative parent–child conversation using respiratory sinus arrhythmia (RSA) at age 12. Social withdrawal in late childhood predicted depressive symptoms at age 12. The combination of high levels of social withdrawal with peers from ages 9–12 and low RSA reactivity with a parent at age 12 predicted higher depressive symptoms at age 15. Withdrawal in multiple social contexts may place boys at risk for depressive symptoms during the vulnerable period of adolescence.
A simple and efficient implmentation approach for single assignment languages

Functional and single assignment languages have semantically pure features that do not permit side effects. This lack of side effects makes detection of parallelism in programs much easier. However, the same property poses a challenge in implementing these languages efficiently. A preliminary implementation of a compiler for the single assignment language, SISAL, is described. The compiler uses reference counts for memory management and copy avoidance. Performance results on a wide range of benchmark programs show that SISAL programs compiled by our implementation run 2-3 times slower on average than the same programs written in C, Pascal, and Fortran, and orders of magnitude faster than other implementations of single assignment languages. Extensions of these techniques for multiprocessor implementations are proposed.
Compact Hankel Forms on Planar Domains

A Hankel form on a Hilbert function space is a bounded, symmetric, bilinear form [., .] satisfying [fx, y] = [x, fy] for a class of multipliers f. We prove analogs of Weyl–Horn and Ky Fan inequalities for compact Hankel forms, and apply them to estimate the related eigenvalues, both for Hardy–Smirnov and Bergman spaces norms associated to multiply connected planar domains. In the case of the unit disk, we investigate the asymptotic of some measures constructed by eigenfunctions of Hankel operators with certain Markov functions as symbols.
FMAC: A fair MAC protocol for coexisting cognitive radio networks

Cognitive radio is viewed as a disruptive technology innovation to improve spectrum efficiency. The deployment of coexisting cognitive radio networks, however, raises a great challenge to the medium access control (MAC) protocol design. While there have been many MAC protocols developed for cognitive radio networks, most of them have not considered the coexistence of cognitive radio networks, and thus do not provide a mechanism to ensure fair and efficient coexistence of cognitive radio networks. In this paper, we introduce a novel MAC protocol, termed fairness-oriented media access control (FMAC), to address the dynamic availability of channels and achieve fair and efficient coexistence of cognitive radio networks. Different from the existing MACs, FMAC utilizes a three-state spectrum sensing model to distinguish whether a busy channel is being used by a primary user or a secondary user from an adjacent cognitive radio network. As a result, secondary users from coexisting cognitive radio networks are able to share the channel together, and hence to achieve fair and efficient coexistence. We develop an analytical model using two-level Markov chain to analyze the performance of FMAC including throughput and fairness. Numerical results verify that FMAC is able to significantly improve the fairness of coexisting cognitive radio networks while maintaining a high throughput.
MOVING BOUNDARY ELECTROPHORESIS IN TRIS BUFFERS

The effects of various organic acids in tris (hydroxymethyV) aminomethane buffers (Tris buffers) on the moving boundary electrophoretic patterns of a bovine lens extract, bovine a-crystallin, and bovine plasma albumin were investigated. The effects of buffer concentration and added neutral salt were studied. Resolution of components and enantiography of patterns improved as the chain length of the acid increased. Tris-valeric acid and Tris-isovaleric acid, 0.05 M, pH 8.6 (0°), appeared to be the best buffers for resolution of bovine lens components. Resolution of the components in the mixture was less complete as the buffer concentration increased. The concentration of the fast component decreased with increase in buffer concentration. The decrease was less in the case of polycarboxylic acids and least in the case of the aromatic acids. The addition of 0.025 M NaCl to the 0.05 M Tris buffers produced little effect upon the resolution of the components. The mobilities were lower when 0.05 M Tris-0.025 M NaCl buffers were used than when 0.05 M Tris buffers were used, but greater than when 0.10 M Tris buffers were used. Evidence is presented for specific buffer and acid effects on the electrophoretic patterns. A quantitative method for expressing the enantiography of the electrophoretic patterns is presented.
Quantitation of the Cell Surface Level of Ld Resulting in Positive Versus Negative Selection of the 2C Transgenic T Cell Receptor In Vivo

The 2C transgenic TCR is positively selected on Kb and is alloreactive for and negatively selected on Ld. To test an avidity model for positive selection, mice were bred to express different levels of surface Ld by varying the number of gene copies encoding beta 2-microglobulin (beta 2m) or Ld heavy chain. Whereas mice expressing 35% Ld (beta 2m+/- Ld+/-) negatively selected the 2C TCR, mice expressing 2% Ld (beta 2m-/- Ld+/-) positively selected the 2C TCR. Furthermore, 2C cytotoxic T lymphocytes selected on 2% Ld showed peptide-specific cytolytic activity against Ld/p2Ca targets. These findings provide clear in vivo evidence that positive selection can occur on very low levels of the same class I antigen capable of negative selection when expressed at higher levels.
Agreement among pediatric ophthalmologists in diagnosing plus and pre-plus disease in retinopathy of prematurity.

Purpose Plus disease has become the major criterion for laser treatment in infants with retinopathy of prematurity (ROP), but its assessment is subjective. Our purpose was to compare quadrant-level and eye-level assessment of plus disease and pre-plus disease among 3 experienced ROP examiners and to report their rate of agreement. Methods One hundred eighty-one high-quality RetCam images from premature infants were graded by 3 of the authors. Dilation and tortuosity were judged separately using a scale of normal or sufficiently abnormal to meet criteria for pre-plus or plus disease. Results There was disagreement on the presence of plus disease for 18 images (10%), on tortuosity sufficient for plus disease (plus tortuosity) for 26 images (14%), and on dilation sufficient for plus disease (plus dilation) for 26 images (14%). Of 67 images judged to have pre-plus disease or worse, there was disagreement on the presence of plus disease for 18 images (27%), on plus tortuosity for 25 images (37%), and on plus dilation for 21 images (31%). For distinguishing plus or pre-plus disease from normal, there was disagreement on pre-plus tortuosity for 38 of 181 images (21%) and on pre-plus dilation for 58 of 181 images (32%). Conclusions Three experienced ROP examiners disagreed frequently on the diagnosis of plus or pre-plus disease when evaluating cropped clinical photographs of infants, many of which had borderline plus disease. Further study is required to determine the implications of these observations on clinical decision making.
Current status of the diagnosis and treatment of thymoma.

Although thymomas are rare neoplasms, they are the most common tumor of the anterior mediastinum in adults. Preferred therapy for these neoplasms is complete surgical resection. If a thymoma cannot be completely resected, postoperative radiotherapy may produce satisfactory results in controlling the tumor. Significant 5- and 10-year survival rates have been recorded for patients with advanced thymomas who have been treated by radiation therapy alone. Chemotherapy may be used in patients with unresectable thymomas as well, but the results are less promising than with radiotherapy. Combinations of radiotherapy and chemotherapy used on patients with unresectable thymomas have produced encouraging results. Surveillance of patients with thymoma should be prolonged because late recurrence (more than 5 years after initial therapy) can be expected in a significant minority of patients. Aggressive therapy of late recurrence, including resection of new tumor masses and pleural metastases, has yielded successive disease-free intervals that validate persistent treatment.
PERFORMANCE, ACCURACY, AND CONVERGENCE IN A THREE-DIMENSIONAL MONTE CARLO RADIATIVE HEAT TRANSFER SIMULATION

A general purpose Monte Carlo computer code for the calculation of radiative exchange factors in three-dimensional enclosures with a nonparticipating medium is described. Capabilities of the code include mixed specular and diffuse reflection models, banded spectral material properties, transmission through external surfaces, and simulation of beam radiation. The ray tracing and surface interaction routines are described, as well as the shading algorithms. The effect of input file parameters on computer lime usage is investigated, and rates of convergence are calculated. Results for run time and accuracy are in good agreement with predictions.
A POWERFUL FRIENDSHIP: THEODORE VON KARMAN AND HUGH L. DRYDEN

During their long personal friendship and professional association, Theodore von Karman (1882-1963) and Hugh L. Dryden (1898-1965) exercised a pivotal if somewhat elusive influence over American aeronautics and spaceflight. Both decisive figures in organizing scientists and engineers at home and abroad, both men of undisputed eminence in their technical fields, their range of contacts in government, academia, the armed forces, industry, and professional societies spanned the globe to an extent unparalleled then as now. Moreover, because they coordinated their activities closely, their combined influence far exceeded the sum of each one s individual contributions. This paper illustrates their personal origins as well as the foundations of their friendship, how their relationship became a professional alliance, and their joint impact on the world of aeronautics and astronautics during the twentieth century.
The use of the changing criterion design in achieving controlled smoking in a heavy smoker: A controlled case study

This study describes the use of the changing criterion design for decreasing smoking rate. Evidence is provided which demonstrates that boundaries exist within which a well-established, high frequency baseline smoking rate (82 cigarettes per day) can be successfully modified and maintained at the rate of 5 cigarettes per day over a 20-month follow-up period. It is concluded that controlled smoking can be a viable alternative for individuals unable or unwilling to quit; further, this goal can be achieved through the changing criterion design, which allows for the demonstration of experimental control in a situation requiring minimal therapist contact.
Microscopic characterization of laser-induced damage performance of large-size KDP and DKDP nonlinear crystals

KDP and DKDP are unique materials for frequency conversion in large-aperture laser systems. Under high power irradiation, a threshold exists above which multiple damage sites are formed in the bulk of crystal plates thus obstructing beam propagation and creating undesirable beam modulations. Damage testing has focused on measuring the irradiation threshold fluences that lead to irreversible material modifications. However, small amounts of damage in optical components have been determined not to hinder system performance in large-aperture laser systems. In this work, we present a new approach to evaluating damage performance that provides statistics on damage pinpoint density, size and morphology as a function of fluence, wavelength and pulse duration and relates that to the resulting beam obscuration. We measure the size of damage sites for different wavelengths, pulse-lengths, and fluences. Different pulse-lengths are approximated by using multiple pulses appropriately delayed with respect to each other. We find that in KDP/DKDP crystals, the size of damage sites strongly depend on the pulse-length, with longer pulses creating larger damage sites. Also examined are ways of laser-annealing to increase the damage resistance.
How state preparation can affect a quantum experiment: Quantum process tomography for open systems

We study the effects of the preparation of input states in a quantum tomography experiment. We show that maps arising from a quantum process tomography experiment (called process maps) differ from the well-known dynamical maps. The difference between the two is due to the preparation procedure that is necessary for any quantum experiment. We study two preparation procedures: stochastic preparation and preparation by measurements. The stochastic preparation procedure yields process maps that are linear, while the preparations using von Neumann measurements lead to nonlinear processes and can only be consistently described by a bilinear process map. A process tomography recipe is derived for preparation by measurement for qubits. The difference between the two methods is analyzed in terms of a quantum process tomography experiment. A verification protocol is proposed to differentiate between linear processes and bilinear processes. We also emphasize that the preparation procedure will have a nontrivial effect for any quantum experiment in which the system of interest interacts with its environment.
Propagation in a fluid medium of a human epidermoid carcinoma, strain KB.

SummaryAn epidermoid carcinoma of the floor of the mouth was cultivated directly onto a glass surface in a medium consisting of 13 amino acids, 7 vitamins, glucose, salts, and 10% human serum. All of the defined components of this medium had previously been shown to be essential for the propagation of the HeLa cell, and all were used at concentrations permitting maximal growth of that cell. The new line (KB) has been grown continuously in this medium for 5 months, and maintains a generation time in the logarithmic phase of growth of approximately 30 hours.
Demystifying seronegative autoimmune pancreatitis

Abstract Background Autoimmune pancreatitis (AIP) has been classified into type 1 and type 2 subtypes. Serum immunoglobulin G4 (IgG4) elevation characterizes type 1 AIP. Type 2 AIP and a subset of type 1 AIP are seronegative, i.e., have normal serum IgG4 levels. Aim We compared the profiles of the three subsets of AIP to identify the unique characteristics of seronegative type 1 AIP and type 2 AIP. Methods We compared the clinical profiles of 69 seropositive type 1 AIP patients, 21 seronegative type 1 AIP patients and 22 type 2 AIP patients. Results Among type 1 AIP, seronegative group had similar clinical profiles when compared to seropositive group except that they were more likely to undergo surgical resection than seropositive patients (p = 0.001). Seronegative type I AIP patients were older (61.9 ± 13.7 vs 45.3 ± 17.4; p = 0.004), and differed in the occurrence of other organ involvement (OOI) (71.4% vs 0%; p 50 years while none of the type 2 AIP had OOI or disease relapse. Conclusions Seronegative and seropositive type 1 AIP patients have similar clinical profiles, which are distinct from that of type 2 AIP. Among the seronegative AIP group, patients are more likely to have type 1 AIP rather than type 2 AIP if they are older than 50 years or have OOI or disease relapse.
Revision of the orchid bee subgenus Euglossella (Hymenoptera: Apidae), part II: The viridis and mandibularis species groups

The second and final part of a revision of the subgenus Euglossella Moure in the orchid bee genus Euglossa Latreille (Apinae: Euglossini) is presented here, redefining the species groups within it to comply with current morphological and molecular phylogenetic hypotheses. We present a fully illustrated account of the species comprising the newly defined viridis and mandibularis species groups, with comparable diagnoses for all species, keys to the new scheme of species groups within the subgenus, and keys for males and females to the species of the two groups here treated. The viridis group as presented here is composed of 12 species, five of them newly described — Euglossa ( Euglossella ) celiae Hinojosa-Diaz & Engel, new species, E . ( E .) subandina Hinojosa-Diaz & Engel, new species, E . ( E .) cetera Hinojosa-Diaz & Engel, new species, E . ( E .) cupella Hinojosa-Diaz & Engel, new species, and E . ( E .) ashei Hinojosa-Diaz & Engel, new species — and one resurrected from synonymy as E . ( E .) azurea Ducke. Euglossa ( Euglossella ) viridis (Perty), E . ( E .) cyanea Friese, E . ( E .) polita Ducke, E . ( E .) perviridis Dressler, E . ( E .) cyanura Cockerell, and E . ( E .) granti Cheesman comprise the remaining species within the group. Females of E . perviridis are described for the first time. The mandibularis group includes three species — E . ( E .) mandibularis Friese, E . ( E .) bigibba Dressler, and E . ( E .) perfulgens Moure. In total, considering the six species previously included in the decorata group, the subgenus now includes a total of 21 species. New country records are presented for E . viridis , E . perviridis , and E . mandibularis . Notes on morphological variation and distribution are included as is a summary of known chemical attractants and floral substrates.
Surface diffusion of oxygen atoms individually observed by STM

Abstract We report on the first dynamical studies with scanning tunneling microscopy (STM). Single excess oxygen atoms migrating on the oxygen-induced (2×1) and c(2×2) reconstructions on Ni(110) and Ni(100), respectively, are detected space and time resolved. In principle, for varying temperature, the data reveal the local diffusion coefficient, the activation energy and the density of adatoms on terraces and at steps. For the Ni(110) (2×1), even the adsorption sites are identified.
A laboratory study on the NO, NO2, SO2, CO and CO2 emissions from the combustion of pulverized coal, municipal waste plastics and tires

This is a laboratory study on the combustion emissions from pulverized solid fuels: NOx (NO and NO2), SO2, CO and CO2. Coal, waste tire crumb and waste plastics, such as poly(styrene), poly(ethylene), poly(methyl methacrylate), poly(propylene) and poly(vinyl chloride) (PVC), were burned in an electrically heated drop-tube furnace at high particle heating rates (104-105 K s−1) and elevated gas temperatures (1300–1600 K). The fuel to air bulk equivalence ratio, φ, was varied in the range of 0.4–1.8. Air or a nitrogen-free mixture of O2CO2Ar were used as oxidizing gases. Results showed that fuels which contain nitrogen generated the highest NOx emissions. Combustion of coal generated four times more NOx than combustion of tire crumb, in proportion to their nitrogen content, and ten times more NOx than that of the nitrogen-free plastics. The specific NOx emissions decreased dramatically (3–6 times) with increasing bulk equivalence ratio for all fuels. However, the NO2/NO ratio increased with the equivalence ratio in the fuel-rich region. Increasing the gas temperature, in the range 1300–1600 K, resulted in 10–25% more NOx, depending on the fuel. Atmospheric nitrogen contributed 20% of the total NOx emissions for coal, 30% for tires and 100% for the plastics. SO2 emissions of the particular coal and tire crumb tested were comparable. While absolute SO2 emissions of coal and tire increased with the equivalence ratio, specific emissions exhibited a mild downward trend. SO2 emissions were higher in the absence of atmospheric nitrogen, especially at fuel-rich conditions. Mild emissions of CO were encountered in the fuel-lean regions, but they increased exponentially in the fuel-rich region accounting for as much as 10% of the carbon at φ = 2. Overall, the CO2 emissions were proportional to the carbon content of the fuels.
Power and Security Issues in the Middle East

Book reviewed in this article: Middle Eastern Security: Prospects for an Arms Control Regime, Efraim Inbar and Shmuel Sandler, editors The Quest for Hegemony in the Arab World: The Struggle over the Baghdad Pact, Elie Podeh
Recognition, Treatment, and Prevention of Endophthalmitis: Appendix

(1989). Recognition, Treatment, and Prevention of Endophthalmitis: Appendix. Seminars in Ophthalmology: Vol. 4, No. 2, pp. 69-83.
Comparison of Extracorporeal Shock Wave Lithotripsy and Percutaneous Nephrostolithotomy for the Treatment of Renal Calculi in Lower Pole Calices

Lower pole calyceal calculi can be treated by percutaneous nephrostolithotomy (PCNL) or by extracorporeal shock wave lithotripsy (ESWL†). In previous studies investigators have noted that stones in lower calices treated with ESWL have a poor clearance rate. This study compared PCNL and ESWL treatments for solitary lower calyceal stones. Thirty-five patients with lower pole calyceal stones were treated with ESWL (Dornier HM3), and 29 patients were treated with PCNL between March 1983 and January 1988. Pretreatment intravenous pyelograms of the ESWL patients were examined, and the length and width of the lower pole infundibulum were recorded. The mean stone diameter was 9 mm (range, 3 mm to 30 mm) in the ESWL group and 10 mm (range, 4 mm to 27 mm) in the PCNL group. All patients in the ESWL group had adequate stone fragmentation (particles < 4 mm). Stone composition was similar for the two groups. A KUB was obtained at a median follow-up of 13 months in 94% of ESWL patients and 90% of PCNL patients. There was a 59% stone-free rate for the ESWL group and an 85% stone-free rate for the PCNL group. The ESWL stone-free rate did not correlate with infundibular width or infundibular length. The ESWL patients spent 2.5 days in the hospital y 6.1 days for the PCNL patients. The PCNL patients had a two-fold greater recovery time (19.3 days y 10 days). Interestingly, there was no difference between the two treatment groups in regard to recurrent stone disease; 10% of ESWL patients had a recurrence within 18 months, and 11% of PCNL patients had a recurrence with 22 months following treatment.
Rifting origin for the vema fracture in the North Atlantic

The mid-Atlantic ridge crest is offset more than 300 km along the E-W trending Vema Fracture valley. The trend of the extremeties of this valley outside the region of recent earthquakes, as well as that of apparently inactive transverse valleys to the south, is somewhat south of east. These observations, and the fact that the valleys to the south apparently do not extend across the ridge crest, strongly suggest that a new pattern of ridge growth and sea-floor spreading, represented by the Vema Fracture valley, has been superimposed on an older one. A geometrical model is proposed for the recent development of the Vema Fracture valley, which is shown to be consistent with other geological and geophysical observations in this region.
THE MITOTIC APPARATUS IN FUNGI, CERATOCYSTIS FAGACEARUM AND FUSARIUM OXYSPORUM

Vegetative nuclei of fungi Ceratocystis fagacearum and Fusarium oxysporum were studied both in the living condition with phase-contrast microscopy and after fixation and staining by HCl-Giemsa, aceto-orcein, and acid fuchsin techniques. Nucleoli, chromosomes, centrioles, spindles, and nuclear envelopes were seen in living hyphae of both fungi. The entire division process occurred within an intact nuclear envelope. Spindles were produced between separating daughter centrioles. At metaphase the chromosomes became attached to the spindle at different points. In F. oxysporum the metaphase chromosomes were clear enough to allow counts to be made, and longitudinal splitting of the chromosomes into chromatids was observed. Anaphase was characterized in both fungi by separation of chromosomes to poles established by the centrioles, and in F. oxysporum anaphase separation of chromosomes was observed in vivo. Continued elongation of the spindles further separated the daughter nuclei. Maturing daughter nuclei of both fungi were quite motile; and in C. fagacearum the centriole preceded the bulk of the nucleus during migration. The above observations on living cells were corroborated by observations on fixed and stained material.
Non-productive paramyxovirus infection: Nariva virus infection in hamsters

The pathogenesis of infection with Nariva virus (NV)—recently classified as a paramyxovirus—was studied in the hamster, an animal closely related to the natural host. Intracranial inoculation of suckling hamsters produces an acute necrotizing encephalitis with large amounts of infectious virus and virus antigen in the brain. In contrast, weanling hamsters have only small amounts of infectious virus and only early in the disease, when they are well; later, when clinically ill, they have a non-productive infection with continuing evidence of viral antigen, but no detectable infectious virus. Weanlings die later than sucklings with less cerebral parenchymal necrosis. The integrity of the immune system affects the expression of NV since brain tissue from anti-lymphocyte serum (ALS) treated infected weanling hamsters have more infectious virus, and for longer periods, than brain tissue from untreated infected weanling hamsters. Changing susceptibility of the host's neural cells may also be involved in determining the course of the illness and expression of the virus since: 1) ALS treatment does not influence the clinical course of the disease or pathology, 2) ALS treated weanlings still have much lower levels of infectious virus than sucklings, 3) infected weanling and suckling hamsters have a similar time course of development of NV neutralizing antibody.
A surface-science-based model for the selectivity of platinum-gold alloy electrodes in zirconia-based NOx sensors

Abstract Recent surface chemistry experiments help explain the operation of an exhaust gas NOx sensor that uses a platinum–gold alloy electrode to selectively remove oxygen but not NO from an interior chamber. The electrode surface must dissociate O2 for removal by electrochemical pumping, but must be at least 100 times less active for dissociating NO. In ultrahigh vacuum studies on stepped platinum single crystals, NO dissociation is strongly suppressed by surface gold coverages as low as 0.4 monolayer (ML), as well as by co-adsorbed oxygen and NO, probably because the dissociation process requires a special ensemble of several unoccupied Pt atoms. Oxygen dissociation is much less affected by surface modifications. In general, the surface composition of an alloy is very different from its bulk composition and depends on gas composition. By considering the energetics of the Pt–Au system we argue that under all conditions of interest for sensor operation the ensembles of free Pt atoms required for NO dissociation are strongly disfavored. A surface chemistry-based explanation is also suggested for the ammonia interference reported for this NOx sensor.
Well-posed constraint-preserving boundary conditions for the AA formulation of Einstein's equations

In this paper, we address the problem of artificial boundary conditions for the symmetric linearized hyperbolic formulation of Einstein's equations introduced in [A.M. Alekseenko, D.N. Arnold, New first-order formulation for the Einstein equations, Phys. Rev. D (3) 68 (6) (2003) 064013, 6 pp.]. We prescribe simple boundary conditions that make the problem well-posed and preserve the constraints.
Free amino acids and cell volume regulation in the elasmobranch, Raja erinacea

Free amino acids comprise a significant fraction of the total intracellular osmolality in skate tissues. The high amino acid concentrations are maintained by active, Na+-dependent transport systems in the cell membranes. Following transfer to a hypo-osmotic environment (dilute seawater) cellular concentrations of free amino acids are reduced mainly as a result of increased rates of outflux but decreased rate of influx can also play a role. Metabolism (oxidation and synthesis) does not appear to play a direct role in the modulation of free amino acid concentrations in skeletal muscle cells and erythrocytes. However, continued release of free amino acids from these cells during hypo-osmotic stress is dependent on the ability of liver and kidney to either oxidize (β-alanine, sarcosine) or excrete (taurine) amino acids at accelerated rates. A scheme for the overall modulation of cellular free amino acids in skate tissues by a combination of membrane transport, metabolism, and excretion is presented.
Fractal chemical kinetics: Reacting random walkers

Computer simulations on binary reactions of random walkers (A + A --* A) on fractal spaces bear out a recent conjecture: (p-~-po I) oct s, where p is the instantaneous walker density and P0 the initial one, andf = d j2, where d s is the spectral dimension. For the Sierpinski gaskets: d= 2, 2f = 1.38 (d~ = 1.365); d = 3, 2f= 1.56 (d s = 1.547); biased initial random distributions are compared to unbiased ones. For site percolation: d = 2, p = 0.60, 2f= 1.35 (d~ = 1.35); d= 3, p = 0.32, 2f= 1.37 (d s = 1.4); fractal-to-Euclidean crossovers are also observed. For energetically disordered lattices, the effective 2f (from reacting walkers) and d s (from single walkers) are in good agreement, in both two and three dimensions.
Laparoscopic suction irrigator for percutaneous removal of renal pelvic bezoar

Candidiasis of the lower urinary tract is common in immunocompromised patients. Two common risk factors are diabetes and a chronic indwelling Foley catheter.1 However, upper urinary tract candidiasis is rare. When present, it may manifest as local and systemic illness. The treatment algorithm combines medical and surgical approaches. Reducing the fungal burden is critical for treating these patients. Conservative therapies include external drainage, systemic antifungal therapy and amphotericin B renal pelvic irrigation.2 When these measures fail, percutaneous surgical debulking of the fungal bezoar is indicated.3 Our case illustrates the use of a laparoscopic suction irrigator for removing renal pelvic fungal bezoars (fig. 1).
Short-term average optical-beam spread in a turbulent medium

On the basis of the extended Huygens–Fresnel principle, a general expression is derived for the short-term average optical-beam spread, as measured with respect to the instantaneous center of energy of the beam, of an initially coherent optical-beam wave propagating in a weakly inhomogeneous medium. The present analysis applies to the near field of the effective coherent transmitting aperture, where the beam wanders (dances) as a whole and does not break up into multiple patches or blobs. Central to the analysis is the short-term average mutual coherence function (MCF) of a spherical wave. This quantity is obtained from the corresponding long-term MCF by removing the random tilt of the wave front. Analytic expressions for the short-term beam spread are presented for the case of a Kolmogorov spectrum and the short-term average MCF derived by Fried. As expected, the short-term, turbulence-induced beam spread is always less than the corresponding long-term beam spread. Analytic and numerical results are given for the short-term average irradiance at focal range f, which is always greater than the corresponding long-term average irradiance.
Clinical efficacy and electropharmacology of continuous intravenous amiodarone infusion and chronic oral amiodarone in refractory ventricular tachycardia

Abstract The clinical efficacy and electropharmacologic effects of continuous inllravenous (i.v.) amiodarone infusion (10 to 20 mg/kg/day for 4 to 7 days) followed by chronic oral amiodarone therapy (400 to 800 mg/day for 24 to 53 days) were evaluated in 17 patients with refractory sustained ventricular tachycardia (VT) or ventricular fibrillation. Intravenous amiodarone infusion prolonged the RR interval (from 754 ± 85 to 860 ± 157 ms, p from 423 ± 22 to 466 ± 31 ms, p 0.05) but prolonged significantly after chronic oral amiodarone (p = 0.025). Mean serum amiodarone concentration was 1.7 ± 1.0 mg/liter with infusion and 1.5 ± 0.6 mg/liter with oral therapy. Intravenous amiodarone infusion suppressed spontaneous VT in 5 of 9 patients with frequent VT recurrences, but had no effect on cycle length of spontaneous VT. Chronic amiodarone therapy either suppressed spontaneous VT recurrences or prolonged cycle length during VT recurrences. VT induction after i.v. amiodarone was not predictive of VT induction or spontaneous VT recurrences after chronic oral amiodarone treatment. Thus, i.v. amiodarone has limited value in acute control of VT and clinical or electrophyslologic response to it is not predictive of long term therapeutic results with amiodarone.
Microbial Transformation of Sulfate in Forest Soils

Incubation of forest soils containing sulfate labeled with sulfur-35 showed rapid conversion of the added sulfate to organic sulfur forms by microbial populations. Activity rates were highest in the forest floor, but significant activity was observed throughout the soil profile. The annual potential sulfur incorporation for forest floor and soil combined is estimated to be 30 kilograms per hectare. The metabolism of inorganic sulfate to organic forms can be a major process in the sulfur cycle, influencing sulfate accumulation and mobility in forest ecosystems.
Bacterial genera isolated from field-collected (Diapausing) and laboratory-reared cotton boll weevils, Anthonomus grandis (Coleoptera: Curculionidae)

Abstract Little data exist on the bacterial flora of the cotton boll weevil, Anthonomus grandis , which is a common insect pest to cotton farmers in the United States. This investigation determined the total numbers of aerobic and anaerobic bacteria in diapausing field-collected boll weevils and active adult laboratory-reared boll weevils. Identifications were made of aerobic genera isolated from field-collected and laboratory-reared boll weevils that had previously been surface sterilized. The genera found, in order of decreasing frequency, in the field-collected boll weevils were Lactobacillus, Erwinia, Flavobacterium, Enterobacter , and Pseudomonas . The genera found, in order of decreasing frequency, in the laboratory-reared boll weevils were Lactobacillus, Pseudomonas, Streptococcus, Erwinia, Enterobacter , and Flavobacterium, Lactobacillus was the most frequently found genus in both groups.
Mechanisms of self-inactivation in anergic T cells

Self-reactive T cells that escape negative selection in the thymus must be inactivated or eliminated in the periphery. In response to a partial or suboptimal stimulation, T cells become anergic and unable to proliferate and express cytokines in response subsequent re-encounters with antigen. Calcium signaling plays a central role in the induction of anergy, causing the activation of a calcium/calcineurin/NFAT-dependent cell-intrinsic program of self-inactivation. This review will focus on our current knowledge on the mechanisms that regulate the expression of an anergyspecific program of gene expression in T cells, and how the proteins encoded by those genes impose a state of functional unresponsiveness by targeting and modulating the activity of crucial events required for the activation of T cells, which include downregulation of TCR signaling and inhibition of cytokine transcription.
Studies in the Static Electrification of Filaments

An apparatus has been constructed to rub filaments together under controlled mechanical and ambient conditions and to measure the charge remaining after separa tion. The apparatus is similar to that of Hersh and Montgomery, with refinements to ohtain better control of mechanical variables and to allow variation of ambient pressure. A photomultiplier has been added near the filaments to detect the incidence of electrical breakdown of the atmosphere. Many of Hersh's findings for 45°-45° rubs have been confirmed, specifically those on reproducibility and triboelectric series. On the other hand, some findings have not been substantiated when the range of vari ahles is extended. For nylon rubbed on polyethylene. the charge q shows a square-root dependence on the normal force F, in place of the linear dependence found by Hersh; the charge shows an inverse proportionality with diameter d, in contrast with the inde pendence noted by Hersh. For tantalum rubbed on nylon. the charge is found to depend on a combinati...
Functional Microanatomy of the Feather-Bearing Integument: Implications for the Evolution of Birds and Avian Flight

A selective regime favoring a streamlining of body contours and surfaces is proposed as having been instrumental in driving the morphological and functional transformations of an unfeathered reptilian integument into a feather-bearing avian one. This hypothesis is consistent with a new, structurally and functionally coherent analysis of the microanatomy of the avian feather-bearing integument as a complex, integrated organ system that includes an intricate, hydraulic skeleto-muscular apparatus of the feathers, a dermo-subcutaneous muscle system of the integument, and a subcutaneous hydraulic skeletal system formed by fat bodies. Key elements of the evidence supporting the new hypothesis are (1) the presence of depressor feather muscles that are not needed as antagonists for the erector feather muscles, but can counteract external forces, such as air currents; (2) the fact that the highly intricate feather-bearing integument represents a machinery to move feathers or to stabilize them against external forces; (3) the crucial role of the coat of feathers in streamlining the body contours and surfaces of birds; (4) the aerodynamic role of feathers as pressure and turbulence sensors and as controllable temporary turbulators; and (5) the critical role that a streamlined body plays in avian flight and is likely to have played in the evolutionary transformations from ecologically and locomotorily versatile quadrupedal reptiles to volant bipedal birds without passing through parachuting or gliding stages. These transformations are likely to have occurred more than once. The ancestral birds were probably small, arboreal, hopping, and using flap-bounding, or intermittent bounding, flight.