cssi/SciSciGPT-SciSciNet huggingface dataset:
Reactive oxygen species generation by seminal cells during cryopreservation.

Abstract Objectives. To test the hypothesis that conventionally used procedures for semen cryopreservation may cause an increase in the production of reactive oxygen species (ROS) by sperm or by seminal leukocytes, which may contribute to poor sperm function following cryopreservation. Methods. Eighteen semen specimens with normal parameters from healthy male donors 22 to 40 years of age were each divided into two portions. The first portion was combined 1:1 with Test Yolk Buffer-Glycerol Freezing Medium and was frozen by gradual cooling into liquid nitrogen (−196°C). The second portion was washed and the cells were resuspended in Sperm Washing Medium (SWM) and incubated at room temperature to serve as controls. After a period of treatment, frozen samples were thawed and semen cells were washed and resuspended in SWM. ROS generation by semen cells from each treatment group was measured on a luminometer. Sperm motility, sperm viability, and sperm membrane integrity were also measured in both control and freeze-thaw samples. To further assess ROS generation by semen cells during the cooling process, aliquots of washed semen cells and purified polymorphonuclear leukocytes (PMNs) were incubated separately at different temperature conditions (37°C, 22°C, 4°C, and −20°C). ROS activity in each treatment group was measured and compared with each other. Results. In both semen cells and PMNs, ROS activity increased significantly during the cooling process. The highest ROS levels were recorded in both groups when cooled to 4°C. The ROS levels were extremely low in samples cooled to −20°C and in freeze-thaw samples, probably due to marked loss of cell viability. Conclusions. Gradual reduction of temperature during the process of semen cryopreservation can cause a significant ROS generation by semen cells. ROS is particularly elevated during cooling if the semen sample is contaminated by more than 0.5 × 10 6 leukocytes. Removal of leukocytes from semen samples or treatment with antioxidants prior to cryopreservation may improve sperm viability and function.
Application of NIR fluorescent markers to quantify expression level of HER2 receptors in carcinomas in vivo

HER2 overexpression has been associated with a poor prognosis and resistance to therapy in breast cancer patients. However, quantitative estimates of this important characteristic have been limited to ex vivo ELISA essays of tissue biopsies and/or PET. We develop a novel approach in optical imaging, involving specific probes, not interfering with the binding of the therapeutic agents, thus, excluding competition between therapy and imaging. Affibody-based molecular probes seem to be ideal for in vivo analysis of HER2 receptors using near-infrared optical imaging. Fluorescence intensity distributions, originating from specific markers in the tumor area, can reveal the corresponding fluorophore concentration. We use temporal changes of the signal from a contrast agent, conjugated with HER2-specific Affibody as a signature to monitor in vivo the receptors status in mice with different HER2 over-expressed tumor models. Kinetic model, incorporating saturation of the bound ligands in the tumor area due to HER2 receptor concentration, is suggested to analyze relationship between tumor cell characteristics, i.e., HER2 overexpression, obtained by traditional ("golden standard") ex vivo methods (ELISA), and parameters, estimated from the series of images in vivo. Observed correlation between these parameters and HER2 overexpression substantiates application of our approach to quantify HER2 concentration in vivo.
Sources of Error in Energy Utilization Studies with Lactating Dairy Cattle

Summary A study was made to evaluate the effect of: (a) hay-to-concentrate ratio in the ration, (b) method of measuring milk energy yields, and (c) method of assessing energy gain or loss due to body-weight change on the coefficient of variation (C.V.) of performance energy (P.E.) data in dairy cattle experiments. The C.V. of P.E. data obtained by combining (a) milk energy, (b) weight-change energy, and (c) maintenance energy allowance was lowest when milk energy secreted was measured by bomb calorimetry and weight-change energy was determined by linear regression from daily body weights. In P. E. data with homogeneous variance as in the standardization period, the C.V. was always reduced when the per cent of concentrate in the ration was used as a covariate in the statistical analysis. To have a high probability of true treatment differences of 5% or less, either the C.V. must be held under 4% or the number of replications employed must be large. Thus, it appears that refinement in experimental procedure that will reduce the C.V. is justified. Use of bomb calorimetry to measure milk energy yield, determining weight change energy by linear regression on daily body weights, and using the per cent concentrate in the ration as a covariable with P.E. data in statistical analysis were effective in reducing the C.V.
Identifying mediating factors of moral reasoning in science education

The purpose of this research was to examine how science content knowledge, moral reasoning ability, attitudes, and past experiences mediate the formation of moral judgments on environmental dilemmas. The study was conducted in two phases using environmental science majors and nonscience majors of college age. Phase One determined if environmental science majors exhibited higher levels of moral reasoning on nontechnical environmental social issues than on general social issues and examined the extent to which possible mediating factors accounted for differences in moral reasoning. Phase Two was qualitative in nature, the purpose of which was to observe and identify trends in conversations between subjects as to how certain mediating factors are revealed as people form moral judgments. The framework on which this study was constructed incorporates a progressive educational position; a position that views science education as being interdisciplinary, and a social means to a social end.
Schrödinger Equation for An Extended Electron

A new quantum mechanical wave equation describing the dynamics of an extended electron is derived via Bohmian mechanics. The solution to this equation is found through a wave packet approach which establishes a direct correlation between a classical variable with a quantum variable describing the dynamics of the center of mass and the width of the electron wave packet. The approach presented in this paper gives a comparatively clearer picture than approaches using elaborative manipulation of infinite series of operators. It is shown that the new Schrodinger equation is free of any runaway solutions or any acausal responses.
WATER RELATIONS OF SELECTED SPECIES OF CHAPARRAL AND COASTAL SAGE COMMUNITIES

Water potentials, leaf resistances to water loss, and relative saturation deficits of selected shrub species of chaparral and coastal sage communities were measured each month from June 1973 through May 1974. Measurements were made at coastal and inland sites in southern California, USA with a pressure chamber and a stomatal diffusion porometer, and by floating leaves until saturated. The drought-deciduous Artemisia californica had water potentials < -65 bars by September. The species of evergreen sclerophylls fell into three groups: (1) A rctostaphzylos glauca and Ceanothlls greggii developed the lowest water potentials (< -65 bars) and showed stomata least responsive to water potential; (2) Rlius ol'ata, Rllus laitiriia, and Rlius initegrifolia had the highest water potentials (^- -25 bars) and stomata most responsive to water potential; and (3) Adlenostouza fasciciulatumii and Heteromiieles arbutifolia showed intermediate water potentials and stomatal responses. The coastal and inland sites did not differ in water relations within species and genus, although water stress occurred earlier in the summer at the coastal site. At the inland site, soil moisture content and plant water potentials were higher on the south-facing slope, indicating less water stress for species there than on the north-facing slope. Slope differences were not as well defined at the coast. Key ivortls: Adenostoma fasciculatum; Arctostaphylos glauca; Artemisia californica; Ceanothus greggii; cliaparral; Heteromeles arbutifolia; leaf resistance; plant water relations; Rhtis integrifolia; Rhtis laurina; Rhus ovata; sage, coastal; Salvia apiana; soltlieri Californiia.
Computer-aided modeling and analysis techniques for determining business information systems requirements

Abstract The paper deals with the problem of determining the information requirements or needs of a business organization. Characteristics of the problem are discussed and several forms of models based on concepts in elementary matrix algebra and graph theory are described. We construct boolean matrices representing either data usage or creation by a process or function in a business organization. Products of the two matrices are represented as directed graphs to depict the flow of information. Two procedures are described for realizing the solutions obtained from the analysis. The applicability to other related areas of information systems research is discussed and an example is presented.
Maternal scaffolding and attention regulation in children living in poverty

Abstract This study examines the relation of maternal scaffolding and children's attention regulation abilities in preschool children from low-income families within the context of a parent–child interaction task and in a child-alone task. Maternal scaffolding behaviors differed for mothers of children with different attention regulation skills. Mothers whose children demonstrated poor attention regulation skills in the parent–child interaction were more likely to verbally engage their children, including more strategic questions, verbal hints, and verbal prompts. Children's level of attention regulation skills interacted with mother's amount of scaffolding to predict performance in the child-alone task. Attention regulation skills were related to independent performance only in the context of high maternal scaffolding. Findings contribute new information important for parent interventions to promote attention regulation skills in children who are at risk for poor academic achievement outcomes.
Irreducible Polynomials Which Divide Trinomials Over GF $\,(2)$

The simplest linear shift registers to generate binary sequences involve only two taps, which corresponds to a trinomial over GF(2). It is therefore of interest to know which irreducible polynomials f(x) divide trinomials over GF(2), since the output sequences corresponding to f(x) can be obtained from a two-tap linear feedback shift register (with a suitable initial state) if and only if f(x) divides some trinomial t(x)=xm+xa+1 over GF(2). In this paper, we develop the theory of which irreducible polynomials do, or do not, divide trinomials over GF(2). Then some related problems such as Artin's conjecture about primitive roots, and the conjectures of Blake, Gao, and Lambert, as well as of Tromp, Zhang, and Zhao are discussed
Type I choledochal cyst in association with familial adenomatous polyposis

Choledochal cysts and familial adenomatous polyposis are infrequent disorders that are often manifest in childhood or in early adult life. The rarity and early presentation of these diseases suggests a genetic basis, which has been established for familial polyposis but not for choledochal cysts. We report a case of a 26-yr-old woman with both disorders and offer an alternative genetics-based etiology for the formation of choledochal cysts.
A Prototype WRF-Based Ensemble Data Assimilation System for Dynamically Downscaling Satellite Precipitation Observations

Abstract In the near future, the Global Precipitation Measurement (GPM) mission will provide precipitation observations with unprecedented accuracy and spatial/temporal coverage of the globe. For hydrological applications, the satellite observations need to be downscaled to the required finer-resolution precipitation fields. This paper explores a dynamic downscaling method using ensemble data assimilation techniques and cloud-resolving models. A prototype ensemble data assimilation system using the Weather Research and Forecasting Model (WRF) has been developed. A high-resolution regional WRF with multiple nesting grids is used to provide the first-guess and ensemble forecasts. An ensemble assimilation algorithm based on the maximum likelihood ensemble filter (MLEF) is used to perform the analysis. The forward observation operators from NOAA–NCEP’s gridpoint statistical interpolation (GSI) are incorporated for using NOAA–NCEP operational datastream, including conventional data and clear-sky satellite obse...
A slicker 3G

The IEEE 802.16 family of standards uses OFDM or OFDMA (orthogonal frequency division multiple access) operating in TDD or FDD mode. We show that OFDM offers a number of advantages for very high data rate applications, whereas OFDMA is proposed for use by remote sites in the uplink. OFDMA recognises both the typical asymmetry in data rates relative to the downlink and is a practical way to manage the characteristic OFDM peak-to-average power problem.
Intrinsic Tumors of the Medulla: Surgical Complications

Intrinsic focal tumor of the medulla oblongata is an uncommon entity. Of the 51 cases presenting for treatment of a brainstem glioma between 1984 and 1990, only 7 were confined to the medulla. Radical excision was performed on each patient. Four of the first 5 patients who were extubated in the recovery room had CO2 retention, with associated respiratory arrest and hypoxia. Three suffered permanent cranial nerve deficits as a result. It is the purpose of this report to describe the serious complications of medullary surgery and to make recommendations as to how they may be avoided.
Origin of stray grain formation in single-crystal superalloy weld pools from heat transfer and fluid flow modeling

Abstract Stray grain formation in laser and electron beam welds on single-crystal alloy CMSX-4 was investigated through heat transfer and fluid flow simulations. The results were combined with a single-crystal growth model and stray grain calculations to investigate the influence of welding parameters on stray grain formation. Stray grain contents were also experimentally measured on laser and electron beam welds prepared over a wide range of parameters. The experimental and simulation results each demonstrate that stray grain content initially increases and then decreases with increasing travel speed. Increases in beam power produce an increase in the stray grain content. The results also demonstrate that restriction of growth along 〈1 0 0〉 directions decreases the magnitude of the temperature gradient and increases the growth rate along the dendrite growth direction (relative to the solidification interface normal). This effect promotes stray grain formation in the pool by increasing the extent of constitutional supercooling.
What's New and Important in College of American Pathologists Inspection for the Clinical Microbiology Laboratory

Abstract Proficiency testing and laboratory accreditation have been focuses of the College of American Pathologists since its inception in 1946. At the outset, the programs were voluntary and designed as educational self-improvement exercises. However, the passage of two major bills in 1967 and 1988 transformed the process into a mandatory and regulatory one — first for hospital laboratories, and then for all laboratories that test human specimens. The college has "deemed" status from the federal government to accredit laboratories, using criteria that meet or exceed federal standards. In 2004, a high-profile laboratory failure concentrated media and congressional attention on oversight of the laboratory industry. As a result, numerous changes have been made by both the government and accrediting organizations. This article provides a summary of what has changed and what has remained the same, with particular attention to microbiology laboratories. Suggested strategies for adapting to the changes are provided.
Dwelling at the margins, action at the intersection? Feminist and indigenous archaeologies, 2005

Este articulo aborda los posibles interconexiones entre lo que podria considerarse arqueologia feminista y arqueologia indigenista. El ensayo pasa de una historia de intersecciones en la Escuela Occidental a una consideracion de ambas arqueologias, sus diferencias y sus posibles intereses comunes, y pregunta “jque puede conseguirse a partir de un enfoque interconectado?” Existen dos dimensiones de la interpretacion arqueologica que integran a los eruditos de ambas arqueologias, la feminista y la indigenista: (1) el lugar y el papel de “la experiencia”, y (2) el uso de las narraciones de cuentos y las tradiciones orales. Se sugieren para la arqueologia algunas metodologias que descolonizan y alguna contra-investigacion. Finalmente, se discuten dos aspectos de la arqueologia en los que la interconexion y la colaboracion podrian ser especialmente fructiferas: en como se sobreentiende el papel del genero y en la arqueologia espacial. Sugiriendo que ambas arqueologias trabajan hacia la transformacion de las practicas arqueologicas, esta revision se propone promover el desarrollo adicional de conciencias de coalicion transformativas. Cet article se situe a l'intersection de ce qui pourrait etre considere comme les archeologies feministes et autochtones. Cet essai va de l'histoire des intersectionalites” dans la pensee occidentale a une consideration de ces deux archeologies, leurs differences et leurs preoccupations communes et pose la question suivante: que pouvons-nous apprendre d'une approche intersectionelle. Deux dimensions de l'interpretation archeologique sont integrales aux modes de pensee des chercheurs feministes et autochtones (1) la place et le role de l'experience et (2) l'utilisation de la tradition orale et de la petite histoire. Des methodologies decolonisatrices et une contre-recherche en archeologie est suggeree. Finalement, nous discutons deux aspects de la recherche en archeologie ou l'intersectionalite et la collaboration sont particulierement enrichissantes: celui de la comprehension des roles sexuels et celui de l'archeologie de l'espace. En suggerant que ces deux archeologies travaillent a la transformation des pratiques archeologiques, cette revision desire encourager le developpement futur d'une conscience coalitionelle transformative.
Geochronology in the Gulf of Mexico. Part I

The geochronology of the Pleistocene sediments in the Gulf of Mexico is currently being investigated. A modification of the Pa231/Th230 dating method is proposed. It consists of the determination of Po215, a daughter of Th227, by alpha spectrometry. This method is feasible if all the Th230 and Pa231 in the sediments is derived from the uranium dissolved in sea water. It is also possible to date sediments by this method if additional land derived Th230 and Pa231 are present, provided they are in the same ratio as they are produced in sea water. It has been found that low Th230/Th232 ratios exist in the Gulf of Mexico indicating that land derived Th232 is present in the sediments. This suggests that some Th230 and Pa231 might have been added to the Gulf sediments by this mechanism. A comprehensive study is therefore under way to determine the Th230, Th232 and Pa231 content of the Mississippi River water and sediments. If the Th230/Pa231 ratio is the same the fresh water sediment as the ratio of their parent uranium isotopes or if the land contribution is determinable, the Th230/Pa231 dating method may be valid for the Gulf of Mexico.
Comparison of four Doppler echocardiographic methods for calculating pulmonary-to-systemic shunt flow ratios in patients with ventricular septal defect

Several methods currently exist for quantifying pulmonary (Qp) and systemic (Qs) shunt flow using Doppler echocardiography, although none is widely utilized. In this study, 39 patients (age 2 months to 12 years, mean 2.1 years) underwent an echocardiographic examination within 1 month of Qp:Qs shunt flow determination by oximetry at catheterization. Qp:Qs was determined by 4 methods that utilized: (1) velocity time integrals and luminal areas to estimate volume flow of the pulmonary artery and aorta; (2) the square of the ratios of pulmonary artery to aorta, multiplied by the ratio of pulmonary to aortic peak flow velocities; (3) inclusion of mitral and tricuspid valve volume flow to pulmonary and aortic volume flow; and (4) ventricular septal defect (VSD) diameter and velocity time integral to calculate left-to-right shunt, which, when added to aortic volume flow (Qs), can be used to estimate Qp. Each of the first 3 methods was statistically correlated to the oximetry Qp:Qs, with r values ranging from 0.54 to 0.66 (p 9 mm/m2), all of whom had bidirectional shunting, were removed (r = 0.90). Thus, we concluded that this latter method demonstrated the best correlation to catheterization-derived shunt flow data, and because this method is somewhat less labor-intensive than the others, should provide clinically useful data well suited for serial evaluation in infants and children with VSD.
Growth and Analysis of Polycrystalline Carbon for MOS Applications

Graphitic polycrystalline carbon (polycarbon) is a candidate material for gate and local interconnect applications in MOS technology. High conductivity polycrystalline carbon films have been grown using Plasma Enhanced Chemical Vapor Deposition. Methane is used as the carbon source gas, and boron trichloride provides the boron doping. In this work, the electrical properties of polycarbon films are studied as a function of deposition temperature, gas-phase boron-to-carbon ratio, and plasma power. A more uniform grain alignment is obtained for samples deposited at low plasma power (~ 3 W) and high growth temperatures (~880°C). In these highly oriented samples, the C-axis tends to be aligned parallel to the growth direction. In-plane film resistivities were obtained by Hall measurements, and it was found that the highly-oriented samples exhibit the lowest resistivity (~300 µΩ-cm). This result is consistent with the higher in-plane mobility in single crystalline graphite. Although the presence of boron trichloride appears to be important for the growth of polycarbon at low temperatures, the boron concentration in the film does not affect the resistivity as strongly as the grain alignment.
Characterization of a low frequency power spectral density f−γ in a threshold model

Abstract This study investigates the modifications of the thermal spectrum, at low frequency, induced by an external damping on a system in heat contact with internal fluctuating impurities. Those impurities can move among locations and their oscillations are associated with a loss function depending on the model. The fluctuation properties of the system are provided by a potential function shaped by wells, in such a way that jumps between the stationary positions are allowed. The power spectral density associated with this dissipation mechanism shows a f − γ tail. The interest of this problem is that many systems are characterized by a typical f − γ spectral tail at low frequency. The model presented in this article is based on a threshold type behaviour and its generality allows applications in several fields. The effects of an external force, introduced to produce damping, are studied by using both analytical techniques and numerical simulations. The results obtained with the present model show that no reduction of the power spectral density is appreciable below the main peak of the spectral density.
Cache-oblivious algorithms, a key to better performance

The cheapening of CPU cores in recent years, created a very complex set of circumstances. As the number of CPU cores per computer became greater, difficulties arose which meant that memory access became the bottle-neck for performance. CPUs of the current day and age far superseded their predecessors. 20 years ago, the frequency of the CPU was equivalent to that of the memory bus. This trend changed during the 1990s as hardware designers were able to increase the CPU frequency at a rapid rate. However, the frequency rate of the memory bus stayed the same for architectural reasons. Hardware designer have since come up with data access acceleration techniques, one of which, is the CPU cache. The workshop provided a walkthrough as to why CPU caches are important for software developers and the various cache algorithms that were designed to exploit the CPU cache without having the size of the cache as an explicit parameter.
Tumor necrosis factor-α and acute-phase proteins in early pregnant ewes after challenge with peptidoglycan-polysaccharide.

Bacterial infection shortly after mating interferes with establishment of pregnancy. Injection of peptidoglycan-polysaccharide (PG-PS), a component of gram-positive bacteria, into sheep on day 5 after mating reduces pregnancy rate. Experiments were designed to evaluate the acute-phase response (APR) in ewes to injection of PG-PS on day 5 after mating (day 0). Catheters were inserted into the jugular and posterior vena cava on day 4. On day 5, ewes were challenged with saline or 30 microg/kg body weight (BW) PG-PS (Exp 1) or 60 microg/kg BW PG-PS (Exp 2). Blood samples were collected every 15 min for 6 h (Exp 1) and every 15 min for 2 h, hourly for 12 h, and at 24, 36, and 48 h (Exp 2). Body temperature and clinical signs of infection were monitored in Exp 2. Plasma was assayed for concentrations of a pro-inflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha); 2 APR proteins, serum amyloid A (SAA) and haptoglobin (Hp); and progesterone (P(4)). Ewes injected with 60 microg/kg BW PG-PS exhibited fever, vaginal discharge, loss of appetite, and lethargy. After challenge with either 30 microg/kg or 60 microg/kg BW PG-PS, TNF-alpha increased in the posterior vena cava. Concentrations of SAA and Hp in the jugular increased after challenge with 60 microg/kg BW PG-PS. Only half (5/10) of the ewes treated with 60 microg/kg BW PG-PS had ultrasonically visible embryos, and none of them had functional corpora lutea (CL) (<1 ng/mL of P(4)) on day 21. On the other hand, 8/9 (88.9%) control ewes had visible embryos and all had functional CL on day 21. Using logistic regression, pregnancy on day 21 was predicted to depend on concentrations of TNF-alpha and Hp on day 5 and concentration of P(4) on day 14. In summary, injection of PG-PS on day 5 after mating resulted in fever; increased concentrations of TNF-alpha, Hp, and SAA on the day of and the day after the PG-PS challenge; and decreased concentrations of P(4) on days 14 and 21. These factors were related to failure to establish pregnancy.
How does psychotherapy work? Findings of the San Francisco psychotherapy research group

Abstract Ideally, psychotherapy research should reflect the complexity of the therapy process and have significant bearing on practice. As an example of such an ideal, the work of the San Francisco Psychotherapy Research Group is described and the Control‐Mastery theory of Joseph Weiss and Harold Sampson is discussed. Two empirical studies, one from an earlier phase of the research and the other a more recent one using the Plan Formulation method are described, noting the development of the group's research over a 20‐year period. Finally, a long‐term psychotherapy case is summarized to illustrate the application of these ideas in practice.
Short term kinetics of polymer adsorption on glass substrate

Abstract Short term kinetics (1 to 60 s) of polymer adsorption on glass and the variation of the adsorption density along the surface have been studied using a new technique. This method also gives information on how the polymer is distributed spatially along the interface. The effect of polymer concentration and chemical pretreatment of the substrate with an inorganic on polymer adsorption is discussed. It appears that polymer adsorption does not take place uniformly and linearly with time. Initiation of polymer adsorption by some surface controlled factors appears to be necessary before it is followed by a rapid polymer uptake.
The use of R-/plus/-1-phenylethylisocyanate in the optical analysis of asymmetric secondary alcohols by gas chromatography

Phenylalkylcarbinol steric purity determination from asymmetric secondary alcohol derivatives separation by gas chromatographic resolution
Group IV Coordination Chemistry of a Tetradentate Redox-Active Ligand in Two Oxidation States

The redox-active ligand N,N′-bis(3,5-di-tert-butyl-2-phenoxy)-1,2-phenylenediamide [N2O2red]4– reacts with group IV metal salts to form six- and seven-coordinate complexes [N2O2red]MLn (M = Ti, L = py, n = 2; M = Zr, Hf, L = thf, n = 3). The redox-active ligand occupies four equatorial coordination sites in these complexes. In the case of the zirconium and hafnium complexes, two axial solvent molecules coordinate to the metal center with a third solvent molecule coordinating in the equatorial plane. In the case of the smaller titanium metal center, only two pyridine solvent molecules coordinate to the metal atom, leaving an open coordination site. All three complexes react with halogen oxidants to afford oxidative addition products [N2O2ox]MCl2Ln (M = Ti, n = 0; M = Zr, Hf, L = thf, n = 1), in which the redox-active ligand is oxidized by two electrons to the cyclohexadienediimine state. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Use of wastewater effluent in agriculture

Abstract The use of domestic sewage and other liquid wastes for irrigation of food and forage crops has been under scrutiny for almost 100 years but the benefits, risks and costs continue to be evaluated, particularly in arid zones. The physical, chemical, biological and hygienic properties of wastewater vary greatly with method of treatment employed. In this paper the several well known generic methods of wastewater treatment and some less known newer methods are examined in detail with respect to these properties in arid zones. Trade offs in land energy and resources are also subjected to stochastic examination.
Some Further Physiological Effects of Cell Division Stimulants and Inhibitors

In two previous papers (1 and 2) a method of fractionating substances from urine and tissues, which stimulate and inhibit the division rate of a protozoan ( Colpidium campylum ), was described. Some of the physiological characteristics of these substances form the subject of the present report. For the purpose of the investigation the stimulating and inhibiting fractions were obtained from beef liver and spleen after the manner already described (2). The activity of these fractions was tested as previously reported (1). Experimental When 2 mg. of stimulator were added to 10 c.c. of the culture medium, the resultant stimulation of the division rate of Colpidium was 108 per cent. As progressive amounts of the stimulator were used, a maximum stimulation of 316 per cent was attained upon the addition of 70 mg. to 10 c.c. of medium. With further additions of the stimulator, however, the degree of acceleration was not increased but, on the contrary, was less marked; thus, 80 mg. in 10 c.c. of media showed only 180 per cent stimulation. The inhibitor, obtained from the same source, added in the proportion of 2 mg. to 10 c.c. of medium inhibited the division rate 48 per cent, while progressive additions increased the effect until with 10 mg. added to 10 c.c. of medium the division rate was inhibited 98 per cent. There is an obvious limit to the degree of inhibition, i.e., 100 per cent, at which extreme we would have either survival of the organisms without any division whatsoever or their death upon administration. Stimulation, in theory at least, has no clearly defined limitations. For these reasons no equivalence between stimulation and inhibition can be deduced with quantitative certainty. The above data are presented graphically in the composite curves in Chart I.
New transition metal dichalcogenides formed at high pressure

Abstract Copper dichalcogenides CuX2 with the pyrite-type structure have been synthesized at high pressure. These materials are superconductors. New pyrite-type dichalcogenides of Ni, Co and Fe have also been prepared by the same technique.
Renaissance of laser interstitial thermal ablation

Laser interstitial thermal therapy (LITT) is a minimally invasive technique for treating intracranial tumors, originally introduced in 1983. Its use in neurosurgical procedures was historically limited by early technical difficulties related to the monitoring and control of the extent of thermal damage. The development of magnetic resonance thermography and its application to LITT have allowed for real-time thermal imaging and feedback control during laser energy delivery, allowing for precise and accurate provision of tissue hyperthermia. Improvements in laser probe design, surgical stereotactic targeting hardware, and computer monitoring software have accelerated acceptance and clinical utilization of LITT as a neurosurgical treatment alternative. Current commercially available LITT systems have been used for the treatment of neurosurgical soft-tissue lesions, including difficult to access brain tumors, malignant gliomas, and radiosurgery-resistant metastases, as well as for the ablation of such lesions as epileptogenic foci and radiation necrosis. In this review, the authors aim to critically analyze the literature to describe the advent of LITT as a neurosurgical, laser excision tool, including its development, use, indications, and efficacy as it relates to neurosurgical applications.
Application of ion scattering techniques to characterize polymer surfaces and interfaces

Ion beam analysis techniques, particularly elastic recoil detection (ERD) also known as forward recoil spectrometry (Frcs) has proven to be a value tool to investigate polymer surfaces and interfaces. A review of ERD, related techniques and their impact on the field of polymer science is presented. The physics of the technique is described as well as the underlying principles of the interaction of ions with matter. Methods for optimization of ERD for polymer systems are also introduced, specifically techniques to improve the depth resolution and sensitivity. Details of the experimental setup and requirements are also laid out. After a discussion of ERD, strategies for the subsequent data analysis are described. The review ends with the breakthroughs in polymer science that ERD enabled in polymer diffusion, surfaces, interfaces, critical phenomena, and polymer modification.
An analysis of the potential land base for energy crops in the conterminous United States

An analysis of the potential land base for energy crops in the conterminous United States has identified 158.6 million ha that can grow short-rotation woody crops (SRWC) and herbaceous energy crops (HEC) without irrigation. Of this land, 145.3 million ha is currently used for agriculture as either cropland or pastureland, but agricultural land needs are anticipated to decline in the future. Both SRWC and HEC may be suitable crops for surplus cropland. Of the capable land base, 91.1 million ha is suitable for SRWC, and 131.1 million ha is suitable for HEC. Suitability is based on an assumption that the land must be capable of energy crop yields of at least 11.2 Mg ha −1 yr−1 with current technology. Most of this suitable land is in the North Central, South Central and Southeastern regions of the United States, although present predictions suggest that future cropland surpluses will occur largely in the Great Plains and Mountain regions of the United States. This paper defines the land suitable for energy crop production and estimates the yield potential of that land. Analyses of the relative economics of energy crop and alternative agricultural land uses will be required before the land base potentially available for energy crop production can be defined.
Opening Pandora's box: understanding the nature, patterns, and 30-day outcomes of intraoperative adverse events.

Abstract Background Little evidence exists regarding the characteristics of intraoperative adverse events (iAEs). Methods Administrative data, the American College of Surgeons - National Surgical Quality Improvement Project, and systematic review of operative reports were used to confirm iAEs in abdominal surgery patients. Standard American College of Surgeons - National Surgical Quality Improvement Project data were supplemented with variables including injury type/organ, phase of operation, adhesions, repair type, and intraoperative consultations. Results Two hundred twenty-seven iAEs (187 patients) were confirmed in 9,292 patients. Most common injuries were enterotomies during intestinal surgery (68%) and vessel injuries during hepatopancreaticobiliary surgery (61%); 108 iAEs (48%) specifically occurred during adhesiolysis. A third of the iAEs required organ/tissue resection or complex reconstruction. Because of iAEs, 20 intraoperative consults (11%) were requested and 9 of the 66 (16%) laparoscopic cases were converted to open. Thirty-day mortality and morbidity were 6% and 58%, respectively. The complications included perioperative transfusions (36%), surgical site infection (19%), systemic sepsis (13%), and failure to wean off the ventilator (12%). Conclusions iAEs commonly occur in reoperative cases requiring lysis of adhesions and possibly lead to increased patient morbidity. Understanding iAEs is essential to prevent their occurrence and mitigate their adverse effects.
Identification of functional genomic regions with copy number alteration in liver cancer

Copy number alterations (CNAs) happen frequently in solid tumors. Several oncogenes and tumor suppressor genes have been identified with CNAs. However, the systematic survey of CNA regulated functions is still lack. By employing systems biology approaches, instead of examining individual genes, we directly identified the spatial functional hotspots in human genome. Total 249 genomic regions, or segments, with 410 enriched biological functions were identified. An aCGH data set of hepatocellular carcinoma (HCC) tumors was employed in this study and several putative affected functions of CNAs were identified. Our results indicate that 4 immune related segments were lost in most of patients. In addition, our data implied these immune related segments might be involved in HCC oncogenesis. The result further demonstrated that our method enables researchers to survey biological functions of CNAs and to construct regulation hypothesis at pathway and functional levels.
A dual adaptive procedure for the automatic determination of iteration parameters for Chebyshev acceleration

Chebyshev acceleration for a symmetrizable basic iterative method u{sup (n+1)} = Gu{sup (n)} + k requires estimates of the extreme eigenvalues m(G) and M(G) of the iteration matrix G. Adaptive procedures are often used in order to obtain good estimates for m(G) and M(G). Some existing adaptive procedures are able to give an estimate of either m(G) or M(G) but not both on any given iteration. In this paper we present an adaptive procedure which can estimate both M(G) and M(G) at the same time and which has other useful properties. Numerical results are given which show the new procedure usually requires fewer iterations than previous procedures. 7 refs., 3 tabs.
Cellular Localization of mRNA for Cellular Retinoic Acid–Binding Protein II and Nuclear Retinoic Acid Receptor-γ1 in Retinoic Acid–Treated Human Skin

Abstract We have previously shown that cellular retinoic acid-binding protein II (CRABP-II), but not cellular retinoic acid-binding protein I (CRABP-I), mRNA expression is markedly induced in human skin by topical retinoic acid. In the present study, we have investigated the pattern of expression of CRABP-II transcripts in 4-d RA-treated human skin by non-radioactive in situ hybridization (n = 5) and Northern analysis (n = 4). RA induced accumulation of CRABP-II transcripts throughout the epidermis, dermal fibroblasts, and endothelial cells as determined by in situ hybridization. In skin treated with vehicle, a faint hybridization signal was observed only in basal layers of the epidermis consistent with low-level expression of CRABP-II mRNA. RA-mediated accumulation of CRABP-II transcripts in skin was also confirmed by Northern analysis. Neither RA nor vehicle induced significant changes in nuclear RA receptor-γ1 or keratin 5 gene expression in skin as determined by in situ or Northern hybridization. These results indicate that RA-induced CRABP-II mRNA accumulation is primarily localized to spinous and granular layers in epidermis, and in superficial dermis.
Inducing explanations for errors in Computer-Assisted Instruction

This paper categorizes error recognition schemes in Computer-Assisted Instruction (CAI) programs and introduces a top-down method of error detection, classification and treatment. Particular attention is given to CAI drill programs in which the set of incorrect responses given by the student is systematically derivable through well- defined error strategies. Since this set of “reasonable” incorrect responses may poten- tially be much larger than possible in a multiple choice format, relatively free-form answers must be allowed. The top-down method is demonstrated in a CAI program (HELPERR—HELP with ERRors) to provide specific diagnoses of errors in arithmetic drill exercises in addition, subtraction, multiplication and division. In limited program testing of HELPERR utilizing student protocols, 81% of the observed systematic errors were successfully identified and an overall success rate of 72% was obtained.
Use of uranium isotopes as a temporal and spatial tracer of nuclear contamination in the environment

Abstract The Fernald Feed Materials Production Center (FFMPC) was established in 1951 to process natural uranium (U) ore, enriched uranium (EU) and depleted uranium (DU). This study tests the utility of U isotopic ratios in sediment cores and lichens as indicators of the aerial extent, degree and timing of anthropogenic U contamination, using the FFMPC as a test case. An 80-cm-long sediment core was extracted from an impoundment located approximately 6.7 km southwest of the FFMPC. Elemental concentrations of thorium (2.7–6.2 μg g −1 ) and U (0.33–1.33 μg g −1 ) as well as major and minor U isotopes were analyzed in the core. The lack of measurable 137 Cs in the deepest sample as well as a natural 235 U/ 238 U signature and no measurable 236 U, are consistent with pre-FFMPC activity. Anomalously elevated U with respect to Th concentrations occur in seven consecutive samples immediately above the base of the core (62–76 cm depth). Samples with elevated U concentrations also show variable 235 U/ 238 U (0.00645–0.00748), and all contain measurable 236 U ( 236 U/ 238 U = 2.1 × 10 −6 –3.6 × 10 −5 ). Correspondence between the known releases of U dust from the FFMPC through time and variations in sediment core U concentrations, 235 U/ 238 U and 236 U/ 238 U ratios provide evidence for distinct releases of both DU and EU. Furthermore, these relationships demonstrate that the sediment core serves as a robust archive of past environmental U contamination events. Samples in the upper 40 cm display natural 235 U/ 238 U, but measurable 236 U/ 238 U ( 236 U/ 238 U = 5.68 × 10 −6 –1.43 × 10 −5 ), further indicating the continued presence of anthropogenic U in present-day sediment. Three local lichen samples were also analyzed, and all display either EU or DU signatures coupled with elevated 236 U/ 238 U, recording airborne U contamination from the FFMPC.
Depression of the guinea pig cochlear temperature caused by anesthesia and ventral‐approach ear surgery

A chronic implant of a thermocouple, on the round window membrane of the guinea pig cochlea, was used to determine the cochlear temperature in awake, anesthetized, and surgically dissected animals. The normal cochlear temperature was equal to the core (rectal) temperature of the guinea pig (38.5 °C) and, in the intact animal, exactly tracks changes in core temperature at least down to the 33 °C level tested here. Ventral surgery to expose the cochlea results in a decrease, to a low value of 31 °C, in cochlear temperature because of the removal of tissue mass overlying the auditory bulla. Effective use of a heating pad and blanket cover, over the body of the guinea pig, will regulate core temperature but the exposed cochlea will always have a lower value than either the temperature measured rectally or in the orophraynx.
Solving Polynomial Systems Using a Branch and Prune Approach

This paper presents {\tt Newton}, a branch and prune algorithm used to find all isolated solutions of a system of polynomial constraints. {\tt Newton} can be characterized as a global search method which uses intervals for numerical correctness and for pruning the search space early. The pruning in {\tt Newton} consists of enforcing at each node of the search tree a unique local consistency condition, called box-consistency, which approximates the notion of arc-consistency well known in artificial intelligence. Box-consistency is parametrized by an interval extension of the constraint and can be instantiated to produce the Hansen--Sengupta narrowing operator (used in interval methods) as well as new operators which are more effective when the computation is far from a solution. {\tt Newton} has been evaluated on a variety of benchmarks from kinematics, chemistry, combustion, economics, and mechanics. On these benchmarks, it outperforms the interval methods we are aware of and compares well with \textit{state-of-the-art} continuation methods. Limitations of {\tt Newton} (e.g., a sensitivity to the size of the initial intervals on some problems) are also discussed. Of particular interest is the mathematical and programming simplicity of the method.
The distal femoral anatomy of Australopithecus

The anatomy of the distal femoral fragments from Sterkfontein is reviewed, including its orthopaedic and biomechanical implications with respect to locomotion pattern. Comparisons are made with other hominids and a number of quadrupedal primates. Items which are considered are the obliquity and robustness of the shaft, the anterior intercondylar groove, the intercondylar notch, and the contour of the medial and lateral articular surfaces. The distinctive hominid status of these specimens is shown by their extensive adaptation to bipedal locomotion. No feature is found which is not fully commensurate with completely bipedal locomotion; rather, their distinctive hominid character points to a need for a reanalysis of the gait pattern in these early Pleistocene hominids.
Further evidence for a 6-h tide above Arecibo

Abstract Since the publication of results suggesting the existence of a 6-h tide in the E region above Arecibo [( Tong et al., 1988) J. geophys. Res.93, 10047–10051], much more data has been collected and analyzed. In particular, the time-height trajectories of middle and upper E region Tidal Ion Layers (TILs) for early January 1989 closely resemble those from early January 1981, which first revealed the presence of a 6-h quasi-periodic intermediate layer structure. Further, the January 1989 observations form an ‘overture’ to the March–May 1989 AIDA (Arecibo Initiative in Dynamics of the Atmosphere) campaign, which yielded a total of 28 days of additional data regarding TIL motion. Interestingly, the AIDA data set is dominated, above about 120 km altitude, by sporadic intermediate layers [( mathews et al., 1993) J. atmos. terr. Phys.55, 447–457] and certainly does not show the consistent 6-h period TIL feature seen in the two January data sets. In reviewing all data collected over the past 10 yr and the extensive 1989 observations in particular, we conclude that the basic TIL structure is controlled by two separate tidal wind patterns. We refer to these as the normal pattern and the ‘deep-winter’ pattern. The normal pattern includes the combination of diurnal and semidiurnal tides, while the deep-winter pattern has an additional 6-h tidal component. The deep winter pattern remains unexplained, but we suggest that the 6-h periodicity, which appears to be phase locked with the semidiurnal tide, is generated via in situ non-linear frequency doubling of the semidiurnal tide. The January 1989 results also manifest a TIL structure, below 100 km altitude, which has not been previously reported.