cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure of 1-tris(trimethylsilyl)silyl-3,4,5,6-tetrakis(trimethylsilyl)cyclohex-1-ene

C27H68Si8,1, monoclinic, P21/n;a=9.849(1)A,b=22.599(3)A,c=18.596(3)A, β=94.78(1)A;Z=4,Dc=0.99 g cm−3,R=035,Rw=0.044, GOF=1.73. Compound1 is obtained in one step by the reductive silylation of PhSiCl3 in the presence of a large excess of Li metal and Me3SiCl. The structure of1 has been studied by X-ray crystallography and solution phase NMR techniques.
Gene transfer in primary cultures of human hepatocytes.

Using liposomes as the mediator of DNA transfer, we were successful in the transfection of human hepatocytes isolated from surgical samples with an E. coli β-galactosidase gene (β-gal). A comparison of transfection efficiency showed that of the four promoters used, cytomegalovirus (CMV) promoter yielded higher transfection efficiencies than Rous sarcoma virus (RSV), Simian virus-40 (SV-40) and human alpha-l antitrypsin (AAT) promoters. These studies represent the first report on the successful transfection of primary cultures of human hepatocytes.
Anomalous segregation during electrodynamic gradient freeze growth of cadmium zinc telluride

Abstract A transient, coupled model has been developed to analyze the segregation of zinc in cadmium zinc telluride (CZT) grown in an electrodynamic gradient freeze (EDG) furnace. The coupled model consists of a local model that solves for time-dependent melt flow, heat transfer, melt–crystal interface position, and zinc distribution in both melt and solid phases and a quasi-steady-state global model that features realistic furnace heat transfer. After verification and validation tests, the model is applied to predict composition patterns in a large-scale CZT EDG growth system previously analyzed by Gasperino et al. [On crucible effects during the growth of cadmium zinc telluride in an electrodynamic gradient freeze furnace, J. Crys. Growth 311 (2009) 2327–2335]. Surprisingly, anomalous zinc segregation is predicted, featuring a non-monotonic axial concentration profile and several local minima and maxima across the boule. A mechanistic explanation is put forth based on the cumulative effect of changes in multi-cellular melt flow structures, a particularly susceptible occurrence for CZT systems. Additional effects of furnace translation rate and solid state diffusion are probed.
Synthesis and characterization of aluminium-phosphorus adducts: X-ray crystal structures of Cl3Al·P(SiMe3)3·C7H8 and Br3Al·P(SiMe3)3·C7H8

Abstract The attempted dehalosilylation reactions between AlX3 (X = Cl, Br) and P(SiMe3)3 in toluene in 1:1 mole ratios afforded only the adducts Cl3Al·P(SiMe3)3 (I) and Br3Al·P(SiMe3)3 (II), respectively. Compounds I and II were characterized by 1H, 13C, 27Al, and 31P solution NMR spectroscopy, as well as partial elemental analysis. In addition, the solid state structures of the toluene solvates of I and II were determined by single-crystal X-ray analysis. Characterization revealed that the solid solvated adducts I and II are isostructural and their crystals are isomorphous. In each compound, the Al and the P atoms reside in tetrahedral environments, with each X3Al·P(SiMe3)3 (X = Cl, Br) molecule associated with one interstitial toluene molecule in the crystals. These adducts are noteworthy in that they possess extremely short, essentially equal AlP bond lengths [for I: AlP = 2.392(4) A, and for II: AlP = 2.391(6) A], which are the shortest found to date in aluminium-phosphorus molecular species.
Protein quality of dried enzymatic hydrolysate from anchovy produced in a spouted bed of inert particles

Summary The anchovy (Engraulis anchoita) is a pelagic fish and due to its abundance in South America shows a sustainable exploitation. The enzymatic hydrolysis of anchovy protein associated to the drying technique in spouted bed was analysed in order to obtain products with the best characteristics. The drying conditions were inlet air temperature, concentration and flow rate of suspension. The degree of hydrolysis of the anchovy suspension was of 3.8%, and its available lysine and specific antioxidant activity were of 86 g kg−1protein and 4.31 mmDPPH kg−1 min−1, respectively. In spouted bed drying, the lowest reduction in available lysine (9%) and loss of specific antioxidant activity (8%) were found at 90 °C, and suspension concentration and flow rate of 65 g L−1 and 200 mL h−1, respectively. The dried product was characterised as a protein source of high biological value due to the essential amino acids profile.
Floorplan sizing by linear programming approximation

In this paper, we present an approximation algorithm by linear programming (LP) for floorplan sizing problem. Given any topological constraints between blocks, we can formulate it as an LP problem with a cost function for the minimum bounding box area. Unlike slicing structures, this approach can handle any topological constraints as well as soft/hard/preplaced blocks, and timing constraints. Empirically, our method needs few iterations to find the optimum solution and shows one order of improvement over previous methods both in run time and capability to handle a larger problem size even on a very limited computing resource PC.
Finite size Wilson loops

Abstract A study of Wilson loop averages for finite size loops is initiated. Within the framework of euclidean four-dimensional lattice SU(2) gauge theory with elementary Wilson action we compute the expectation values of all rectangular loops to 12th order in the strong coupling expansion. The leading term for weak coupling is evaluated for loops up to 4 × 4. A comparison to Monte Carlo data is presented. Other related issues are also discussed.
Chromatin structure as a mediator of aging

The aging process is characterized by gradual changes to an organism's macromolecules, which negatively impacts biological processes. The complex macromolecular structure of chromatin regulates all nuclear processes requiring access to the DNA sequence. As such, maintenance of chromatin structure is an integral component to deter premature aging. In this review, we describe current research that links aging to chromatin structure. Histone modifications influence chromatin compaction and gene expression and undergo many changes during aging. Histone protein levels also decline during aging, dramatically affecting chromatin structure. Excitingly, lifespan can be extended by manipulations that reverse the age-dependent changes to chromatin structure, indicating the pivotal role chromatin structure plays during aging.
Neuropeptide production by small cell carcinoma: vasopressin and oxytocin as plasma markers of disease.

Vasopressin (VP) and oxytocin (OT) were evaluated as tumor markers for small cell carcinoma of the lung by measuring the concentrations of these hormones in plasma samples obtained from patients at the onset of therapy and during treatment. Patient levels of VP before treatment ranged from 0.9–116 pmol/L, and this hormone was elevated (>2.4 times) in 37 of 80 patients (46%) when values were compared to those of 25 healthy volunteers (normal mean, 2.13 ± 0.15 pmol/ L). Seventeen patients with elevated arginine VP displayed symptoms of the syndrome of inappropriate secretion of antidiuretic hormone. Patient levels of OT ranged from 0.3–124 pmol/ L, and OT was elevated (>2.4 times) in 14 of 72 patients (19%) compared with values in normal subjects (normal mean, 2.23 ± 0.34 pmol/L). Both hormones were elevated in 6 patients. A positive response to treatment (partial or complete remission) was associated with reductions of elevated VP to 34.6 ± 4.0% and of elevated OT to 34.7 ± 7.5%, of values before treatment...
NMR Measurement of the Hyperfine Constant of an Excited State of an Impurity Ion in a Solid

An optically detected NMR measurement of the hyperfine tensor for an excited state of an impurity rare-earth ion (${\mathrm{Pr}}^{3+}$) in a solid (LiY${\mathrm{F}}_{4}$) is reported. The results have been used to obtain for the first time a measured value of the hyperfine interaction constant ${A}_{j}=616\ifmmode\pm\else\textpm\fi{}51$ MHz of the $^{1}D_{2}$ excited state. This is somewhat smaller than the calculated value of 754 MHz.
Mechanical Interconnects to Silicon Integrated Circuits

There are three predominant interconnection technologies in use today for silicon integrated circuits: wire bonding; TAB (tape automated bonding); and C4 (controlled collapse chip connection). This paper briefly reviews each of these technologies for their strengths and weaknesses but focuses especially on wire bonding for single chip VLSI applications. Although wire bonding has been in widespread use ever since the invention of the small scale integrated circuit, the technique is still applicable for today’s much larger and denser chips. With leadcounts up to 250 or even higher, many challenges are presented for equipment accuracy and speed and in package design, where novel techniques often are required to prevent the package from being the limiting factor in chip interconnection. These challenges are discussed in some detail. The paper concludes with a discussion of the future direction for mechanical connections as influenced by the technical and cost requirements of both the chip and the system in which it resides.
Solar oblateness, excess brightness, and relativity

New observations show a small difference between the sun's polar and equatorial limb darkening functions. This excess equatorial brightness varies in time and can be of sufficient magnitude to account for the solar oblateness inferred by Dicke and Goldenberg from their measurements. This removes the serious consequence of their work for Einstein's general theory of relativity. The problems of a solar-edge definition and the derivation of a solar mass quadrupole moment are discussed.
A Historical Overview and Military Perspective on Fluid Resuscitation, Blood Salvaging Techniques, and Blood Substitutes

a T 0 CONSERVE the fighting strength" .1. is the mission of the Army Medical Department and the overall objective of military medicine. Warriors of the United States military are constantly reminded during their training that an efficient and state-of-the-art medical system is ready and anticipating the medical needs if they are wounded during combat. The assurance that the most advanced medical care in the world is available to them in the event they are injured is an important factor in preparing young soldiers for battle. Many of the current protocols and treatment modalities that are used in both military and civilian trauma resuscitation was born out of experiences and information learned under battlefield conditions. This report will introduce the reader to a historical overview of the beginnings of anesthesia in the military and the impact battlefield medicine has had in the development of civilian trauma management.
Measurement of the Sensitivity and Photometric Accuracy of FT-IR Spectrometers:

A method has been developed to investigate the sensitivity and photometric accuracy of a Fourier transform infrared (FT-IR) spectrometer by statistically analyzing a set of spectra of a 75 μm thick film of polyethylene terephthalate (PET). These tests were applied to three commercial FT-IR spectrometers. Although the photometric accuracy of all three instruments was generally better than 0.1%, small artifacts that could not be removed by signal averaging were often observed where strong bands should have a transmittance of less than 0.01%. Binding of the moving mirror of one of the spectrometers appeared to degrade its performance. When the standard deviation of the noise on 100% lines was calculated in the conventional way, none of the instruments gave efficient signal averaging after 25 scans had been coadded, because of small slopes in the baseline. By calculation of the noise level by successive difference, signal averaging was improved, but even with this approach the noise level on one of the instruments did not decrease after 100 scans had been averaged.
Dynamics of immiscible-fluid displacement in a capillary tube.

Through first-principles hydrodynamic calculations, the macroscopic behavior of the displacement of immiscible fluids in a capillary tube is linked to the microscopic parameters governing the dynamics of the moving contact line. Comparison with experimental data reveals that the contact line is dragged by a frictional force varying as U x , where U is the mean flow velocity and x ≃ 1/2
Ground state in CeAl3: a Ce(Al1−xMx)3 study with MGa, Si, Ge and Sn

Abstract We present the results of an investigation of the ground state in CeAl 3 via substitution of Ga, Si, Ge and Sn for Al in Ce(Al 1− x M x ) 3 . Anomalies in the low temperature specific heat, magnetic susceptibility and electrical resistance reveal an antiferromagnetic ground state for all samples. The data of CeAl 3 fit easily to the results of our doping series. We conclude that the anomalies in the low temperature data of CeAl 3 are due to antiferromagnetism. Antiferromagnetic correlations or even an ordered magnetic state may be present in this compound. These correlations also contribute to the high value of the Sommerfeld-coefficient γ. An evaluation is made as to which parameters are decisive for the magnetic behaviour of CeAl 3 and its doped derivatives.
Laser irradiation of the guinea pig basilar membrane.

Background and Objectives The cochlea is the part of the inner ear that transduces sound waves into neural signals. The basilar membrane, a connective tissue sheet within the cochlea, is tonotopically tuned based on the spatial variation of its mass, stiffness, and damping. These biophysical properties are mainly defined by its constituent collagen fibers. We sought to assess the effect of laser irradiation on collagen within the basilar membrane using histological analysis. Study Design/Materials and Methods Four excised guinea pig cochleae were stained with trypan blue. From these, two were irradiated with a 600 nm pulsed dye laser and two were used as controls. Collagen organization was visualized using polarization microscopy. Results Laser irradiation reduced the birefringence within the basilar membrane as well as within other stained collagen-containing structures. Larger reductions in birefringence were measured when more laser pulses were given. The effects were similar across all turns of each cochlea. Conclusions Laser irradiation causes immediate alterations in collagen organization within the cochlea that can be visualized with polarization microscopy. These alterations may affect cochlear tuning. Ongoing research is aimed at analyzing the effect of laser irradiation on cochlear function. It is conceivable that this technique may have therapeutic benefits for patients with high-frequency sensorineural hearing loss. Lasers Surg. Med. 35:174–180, 2004. © 2004 Wiley-Liss, Inc.
Pumpkin fruit rot in North Carolina caused by Phytophthora nicotianae.

In 1999, during an evaluation of pumpkin (Cucurbita pepo) fruit for susceptibility to naturally occurring postharvest diseases, a soft rot of unknown etiology was noted. No fungal growth or sporulation was seen on the fruit surface and no root or crown rot was observed in the field. When fruit were cross-sectioned, masses of white, floccose mycelium covering large sections of the seed cavity were observed. Rot was observed in 21 fruit (6.4% of the total). The fungus was isolated from symptomatic fruit on a modified P10ARPH agar medium, semi-selective for Phytophthora spp. (2). Isolates from eight fruit formed papillate, ovoid sporangia, abundant chlamydospores, and colonies characteristic of P. nicotianae (1). No oospores were produced. Four sound pumpkin fruit (cv. Early Autumn) were inoculated with four isolates (one isolate per fruit). Each isolate was recovered from a different fruit. Pumpkins were surface sterilized at the point of inoculation by wetting with 70% ethanol. Inoculation was done by removing a small amount of mycelium from pure culture using a sterile, wooden toothpick and inserting it 2 cm deep into opposite sides of the mid section of sound fruit (two inoculations per fruit). Control fruit were punctured with sterile toothpicks (once per fruit). First symptoms appeared 4 days after inoculation at room temperature (22 to 24°C). Symptoms consisted of circular, water-soaked areas originating from the point of inoculation. Average diameter (based on four measurements on two fruit) of the water-soaked lesions were 3 cm at first appearance (i.e., 4 days) and 11 cm 10 days after inoculation. No symptoms developed on controls. When symptomatic fruit were cross-sectioned, masses of white, floccose mycelium were noted. Reisolation of this mycelium onto selective medium yielded P. nicotianae, thus fulfilling Koch's postulates. This is the first report of P. nicotianae causing fruit rot of pumpkins. References: (1) D. C. Erwin and O. K. Ribeiro. 1996. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN. (2) H. D. Shew. Phytopathology 77:1090, 1987.
A review of Neospora caninum and neosporosis

Neospora caninum is a recently recognized protozoan parasite of animals, which until 1988 was misidentified as Toxoplasma gondii. Its life cycle is unknown. Transplacental transmission is the only recognized mode of transmission. It has a wide host range, but its zoonotic potential is unknown. Neosporosis is a major cause of abortion in cattle in many countries. It is also an important cause of neuromuscular paralysis in dogs. This paper reviews information on parasite structure, life cycle, biology, clinical signs, diagnosis, treatment and control.
The African honeybee in Peru: an insect invader and its impact on beekeeping.

Abstract In 1956 scientists introduced a honeybee race, Apis mellifera scutellata, from East Africa into Brazil. This honeybee subsequently escaped from captivity, hybridized with existing honeybee populations and has diffused over much of South America. This paper examines the impact of this diffusion in one South American country, Peru, comparing beekeeping practice and management techniques in the region infested with the aggressive hybrid and in the region free of the hybrid. The study reveals consistent differences between the two regions in almost all criteria examined. Beekeepers in the African region are characterized by the use of more modern equipment, better management techniques, and more successful and commercially orientated beekeeping operations. While the presence of the African honeybee has been bothersome to those Peruvian beekeepers with it in their apiaries, the bee has proved to be neither as damaging nor as disruptive as is frequently suggested. Indeed, Peruvian beekeepers have adapted to the bee's presence with comparative ease and with no organized assistance from public or private agencies. The results of this study suggest that the impact of the African bee's arrival in central and northern Mexico and in the southern United States will not be nearly as disruptive and severe as many people believe.
Permeable reactive biobarriers for in situ Cr(VI) reduction: Bench scale tests using Cellulomonas sp. strain ES6

Chromate (Cr(VI)) reduction studies were performed in bench scale flow columns using the fermentative subsurface isolate Cellulomonas sp. strain ES6. In these tests, columns packed with either quartz sand or hydrous ferric oxide (HFO)-coated quartz sand, were inoculated with strain ES6 and fed nutrients to stimulate growth before nutrient-free Cr(VI) solutions were injected. Results show that in columns containing quartz sand, a continuous inflow of 2 mg/L Cr(VI) was reduced to below detection limits in the effluent for durations of up to 5.7 residence times after nutrient injection was discontinued proving the ability of strain ES6 to reduce chromate in the absence of an external electron donor. In the HFO-containing columns, Cr(VI) reduction was significantly prolonged and effluent Cr(VI) concentrations remained below detectable levels for periods of up to 66 residence times after nutrient injection was discontinued. Fe was detected in the effluent of the HFO-containing columns throughout the period of Cr(VI) removal indicating that the insoluble Fe(III) bearing solids were being continuously reduced to form soluble Fe(II) resulting in prolonged abiotic Cr(VI) reduction. Thus, growth of Cellulomonas within the soil columns resulted in formation of permeable reactive barriers that could reduce Cr(VI) and Fe(III) for extended periods even in the absence of external electron donors. Other bioremediation systems employing Fe(II)-mediated reactions require a continuous presence of external nutrients to regenerate Fe(II). After depletion of nutrients, contaminant removal within these systems occurs by reaction with surface-associated Fe(II) that can rapidly become inaccessible due to formation of crystalline Fe-minerals or other precipitates. The ability of fermentative organisms like Cellulomonas to reduce metals without continuous nutrient supply in the subsurface offers a viable and economical alternative technology for in situ remediation of Cr(VI)-contaminated groundwater through formation of permeable reactive biobarriers (PRBB).
Electronic structure, statistical mechanical simulations, and EXAFS spectroscopy of aqueous potassium

We investigate the solvation structure of aqueous potassium ions, using a combination of electronic structure calculations, statistical mechanical simulations with a derived polarizable empirical potential and experimental measurement of the extended X-ray absorption fine structure (EXAFS) spectra. The potassium K-edge (at 3,608 eV) EXAFS spectra were acquired on the bending magnet of sector 20 at the Advanced Photon Source, at ambient conditions and for the concentrations of 1 and 4 m KCl. We focus on the coordination distances and the degree of disorder of the first hydration shell as determined by electronic structure calculations, molecular dynamics simulations and experimental measurement. Finally, we characterize the changes of the structure in the first hydration shell with increasing temperature as predicted by molecular simulation
Use of isoproterenol in the evaluation of aortic and pulmonic stenosis.

Abstract The effect of isoproterenol on the peak systolic pressure gradient was studied in 45 children with some form of aortic or pulmonic stenosis. An increase in the gradient was observed in 43. It is suggested that this means of study may provide valuable ancillary information in the evaluation of these lesions.
Assessing the Role of ortho-Substitution on Polychlorinated Biphenyl Binding to Transthyretin, a Thyroxine Transport Protein

Abstract ortho-Substituted polychlorinated biphenyls (PCBs) make up a large part of the PCB residue found in the environment and human tissues. Our laboratory as well as others have demonstrated that ortho-substituted congeners exhibit important biological activities by aryl hydrocarbon (Ah) receptor-independent mechanisms, including changes in second messenger systems necessary for normal cell function and growth. Previous structure-activity relationship (SAR) studies on second messengers and transthyretin (TTR; prealbumin) binding focused little attention on the ortho-substituted PCBs. Disruption of thyroid hormone (TH) transport is one potentially important mechanism by which PCBs can alter TH homeostasis. A more systematic study of PCB binding to TTR, a major TH transport protein, was undertaken, in which the role of ortho-substitution was more thoroughly investigated. Results from this study indicated that the ortho-only substituted series showed significant binding activity and the relative affinities were 2,2′,6 > 2,2′ = 2,6 ⪢ 2 = 2,2′,6,6′. As anticipated on the basis of steric considerations, bromine was shown to be more active as an ortho-substituent where the relative affinity of 2,2′-Br was equivalent to 2,2′,6-Cl. The congener patterns (di-meta-substitution in one or both rings) most closely resembling the diiodophenolic ring of thyroxine (T4) showed the highest binding activity. Multiple ortho-substituents were shown to decrease binding activity in such patterns. Congener patterns (single meta-substitution in one or both rings) more closely resembling the monoiodophenolic ring of T3 showed significantly lower binding activity, consistent with the relatively low binding activity of T3 and smaller size of chlorine compared to iodine. The addition of ortho-substitution to such patterns gave variable results depending on the substituent relationship (adjacency or nonadjacency) to the pattern. Some patterns such as 2,2′,4,4′,5,5′ showed good binding activity and represent common congeners in the commercial Aroclor mixtures and in the environment. The binding potencies of ortho-PCBs to TTR may represent a signature SAR that predicts specific biologic/toxic effects. In this regard, the binding potencies were consistent with measured biological activities of these PCBs, including effects on cell dopamine content, Ca2+ homeostasis, and protein kinase C translocation in neuronal cells and brain homogenate preparations.
Teaching Chinese as a Foreign Language: Theories and Applications edited by EVERSON, MICHAEL E., & YUN XIAO

The article reviews the book "Teaching Chinese as a Foreign Language: Theories and Applications," edited by Michael E. Everson and Yun Xiao.
Imaging Three-Dimensional Heliosphere in EUV

The glow of interstellar plasma and solar wind pickup ions and solar wind emissions at 30.4 nm provide a way of exploring important physical processes in the heliosphere. Imaging the heliosphere at this wavelength with high spectral resolution will map the heliopause, probe pickup ions in the solar wind, and reveal the three-dimensional flow pattern of the solar wind, including in the regions over the sun’s poles. The required high-throughput, high-resolution spectrometer for diffuse radiation should be able to measure 1 mill i-Rayleigh irradiance in 10000 seconds with a 0.005-nm spectral resolution across pixels subtending a few degrees of celestial arc. The desired performance characteristics can be achieved by combining multiple entrance slits with an optimized spectrometer design. We present a concept of a space experiment to image the heliosphere at 30.4 nm and discuss the scientific rationale and required instrumentation.
Consumption of Low Larkspur (Delphinium nuttallianum) by Grazing Sheep

Abstract Low larkspur ( Delphinium nuttallianum Pritz.) poisoning causes serious economic loss to livestock producers that graze cattle on foothill and mountain ranges in western North America. In general, all Delphinium spp. are five times less toxic to sheep than to cattle. Because low larkspurs are less toxic to sheep than cattle, grazing sheep before cattle on rangelands with dense populations of low larkspur can reduce larkspur density and risk of poisoning to grazing cattle. All previous published work on sheep and larkspur interactions has involved tall larkspurs. This series of studies was conducted to determine if sheep would consume sufficient low larkspur to reduce subsequent risk to cattle. Four summer trials were conducted in Collbran, Colorado, and Soda Springs, Idaho on pastures with dense (> 9 plants · m −2 ) low larkspur populations. In all trials, sheep ate very little low larkspur ( −1 for 9 d), sheep consumed little low larkspur, but animals appeared to trample much of the low larkspur. Toxic alkaloid concentrations in low larkspur ranged from 1.1 mg · g −1 to 1.6 mg · g −1 in all trials. The use of sheep to graze low larkspurs to reduce subsequent consumption by grazing cattle does not appear to be a viable option.
Death, Friendship, and Female Identity During New England's Second Great Awakening

The memoirs of pious Christians, frequently edited by family members or intimate friends and carefully based on their extant papers, proliferated in the first half of the nineteenth century. These lives document the legacy of the Didactic Enlightenment of the previous century in their preoccupation with death and inclusive friendship, their refusal to draw sharp boundaries between the public and the private, the spiritual and the temporal and in their appreciation for the rational capacity of women. This study focuses on the life of Mary Hawes Van Lennep (1821–1844), missionary wife to Turkey, as traced by her mother, wife of the prominent Hartford, Connecticut preacher, Rev. Joel Hawes. It argues that friendship, as a moral and spiritual culture of bonding and separation, disciplined parents, children and friends alike and has particular significance for female identity formation. It also concludes that these evangelical memoirs are an important source for understanding a particular historical effort to ...
Halobacterium saccharovorum sp. nov., a carbohydrate-metabolizing, extremely halophilic bacterium.

The previously described extremely halophilic bacterium, strain M6, metabolizes a variety of carbohydrates with the production of acid. In addition, the organism produces nitrite (but no gas) from nitrate, is motile, and grows most rapidly at about 50 C. These characteristics distinguish it from all previously described halophilic bacteria in the genus Halobacterium. It is suggested that it be designated as a new species, Halobacterium saccharovorum.
Unnatural monopoly in telecommunications

Abstract There has been considerable disagreement, especially in the USA, over whether the telecommunications industry is a natural monopoly. The same data have been used to reach opposite conclusions and then to support or oppose regulatory intervention. But Professor Wenders argues that there is little that is ‘natural’ about the data being used, they themselves are affected by the incentives given by protected regulation, hence no conclusions can be drawn from them about natural monopoly.
Patch clamping the outer mitochondrial membrane.

Intact giant mitochondria isolated from the liver of mice fed a diet containing cuprizone were studied using patch microelectrodes. The current-voltage curves were nonlinear, suggesting the presence of voltage-sensitive channels. In the negative range of voltage, the channels appear to close with increasing magnitude of the voltage. The dependence of the conductance on voltage is similar to that of the outer membrane channels (VDAC) studied in planar bilayers. Occasionally, over a narrow range of positive potentials, the conductance also decreases as in the bilayer studies. However, more frequently the conductance increases sharply in a completely reversible manner at potentials greater than 10 to 20 mV. The increase in conductance with voltage may be interpreted as a major rearrangement of membrane components. Qualitatively comparable results were obtained using fused outer membranes isolated fromNeurospora mitochondria.
Oxygenation in status asthmaticus improves during ventilation with helium-oxygen

Objectives:To determine the effect of breathing helium-oxygen (HELIOX) mixtures on pulmonary gas exchange during severe asthma.Design:A retrospective case-match control design was used to compare the changes in alveolar to arterial gradient [(A-a)gradient] in the first 2 hrs of mechanical ventilatio
Remote Sensing: An Important Tool for Oceanography

The Graduate School of Oceanography of the University of Rhode Island has established a remote sensing facility whose process of development can serve as a guide to other medium-sized institutions. Implementation steps, costs, and technical processes needed to convert suitable software from one computer to another are discussed.
Allowable coefficient perturbations with preserved stability of a Hurwitz polynomial

Given a polynomial P(s) = ansn + an−11Sn−1 + … -+ a1s + a0 which satisfies the Routh-Hurwitz criterion, a procedure is given for finding non-conservative upper bounds on the allowable variations of the coefficients such that the perturbed polynomial maintains the stability property.
Participation of growth factor signal transduction pathways in estradiol facilitation of female reproductive behavior.

Estradiol (E2) regulates female reproductive behavior (lordosis) by acting on estrogen-sensitive neurons. We recently showed that E2 facilitation of lordosis behavior requires concurrent activation of brain IGF-I receptors. The present study confirmed this finding and sought to identify the downstream signaling pathways involved in estrogen/IGF-I priming of lordosis. Intracerebroventricular infusions of a selective IGF-I receptor antagonist were administered to ovariectomized rats every 12 h beginning 1 h before the first of two daily E2 injections. IGF-I receptor blockade partially inhibits lordosis if the antagonist is infused throughout the 2-d estrogen treatment period but not if it is administered only during the first or last 12 h of estrogen treatment. Because E2 and IGF-I can activate phosphatidylinositol-3-kinase (PI3K) and MAPK, we infused agents that block PI3K and/or MAPK activity as described above. Both PI3K inhibitors (wortmannin and LY294002) and MAPK inhibitors (PD98059 and U0126) partially attenuate lordosis when administered during estrogen priming. None of these drugs modifies lordosis if they are infused only once, during the last 12 h of estrogen treatment. When both wortmannin and PD98059 are infused during E2 priming, lordosis behavior is completely abolished. These data suggest that activation of both PI3K and MAPK by E2 and IGF-I mediates hormonal facilitation of lordosis behavior. (Endocrinology 144: 3828 –3835, 2003)
Mass transfer in plane and square ducts

Abstract A numerical mass transfer analysis for plane and square duct geometries for developing and fully-developed scalar transport with laminar flow is described. A methodology for prescribing stream-wise periodic scalar boundary conditions under conditions of constant-transformed-substance state, is detailed. The solution to the fully-developed mass transfer problem is presented in terms of driving force, blowing parameter and normalised conductance. A suitably-defined polarisation factor is shown to be functionally equivalent to the former. The data compress onto a single curve with good correspondence to the 1-D convection–diffusion solution, except for high rates of wall injection or suction.
Comparison of genetic and anthropological interpretations of population isolates in Aguacatenango, Chiapas, Mexico.

Intensive demographic and genetic studies were made of Aguacatenango, a partial isolate population in Chiapas, Mexico. The census showed higher rates of birth than mortality, with a stable population maintained by emigration. Complete enumeration showed many discrepancies between the ideal and actual mating patterns. Though ideally an endogamous town, many marriages were to outsiders. Also many occurred between the two allegedly endogamous barrios of the town. Blood group determinations on a third of the population provided a second description of the isolate. This description suggested that although the population is nearly a homogeneous genetic unit, the elder residents of one barrio show genetic differences from those of the other. That the barrios might have indeed been genetic isolates was further suggested by a better fit to Hardy-Weinberg equilibria for each barrio separately than for the isolate as a whole. These blood group data were compared to blood group data on one other isolate in the region revealing marked gene frequency differences. It is suggested that similar studies are needed on many populations if the effects of particular population structures on gene drift and selection are to be elucidated.
Superconductive crossbar system for communication applications

Abstract This paper reviews current efforts toward the integration of a high-speed crossbar switch for digital communication applications. This system is an intelligent switching matrix for 128 inputs and 128 outputs, each capable of 2 Gbs (10 9 bits per second). An array of Josephson junction integrated circuits are interconnected with the use of a superconductive multichip module maintained at 4.2 K. This module is connected to room-temperature electronics by means of flexible cables, each containing impedance-matched microstrip transmission lines. Room-temperature interface electronics will permit interconversion between standard level input/output signals and Josephson junction logic levels.
Vibrational analyses of silacyclopent-3-enes

Abstract The complete i.r. and Raman spectra of silacyclopent-3-ene, silacyclopent-3-ene-1,1-d2, 1,1-difluoro-1-silacyclopent-3-ene, and 1,1-dichloro-1-silacyclopent-3-ene have been recorded and the vibrations have been assigned. The spectra strongly suggest that each of the molecules is planar with C2v symmetry. The observed i.r. band types are consistent with the structures estimated for these molecules. A normal coordinate calculation utilizing a general quadratic force field has been carried out for each molecule. Thirty-seven different non-zero force constants were used to obtain a good fit with the sixty-four observed frequencies for the hydride and deuteride. When these constants were transferred to the fluoride and chloride, and when the silicon-halogen force constants were readjusted, a satisfactory fit was obtained for these molecules. Considerable mixing of many vibrational modes, including several SiX2 motions, was found for all four molecules.
Preliminary crystallographic analysis of an enzyme involved in erythromycin biosynthesis: Cytochrome P450eryF

Cytochrome P450eryF was overexpressed in Escherichia coli and purified in high yield. Crystals of the protein in the presence of the substrate, 6-deoxyerythronolide B, have been obtained by the hanging drop vapor diffusion method, using polyethylene glycol 4000 as a precipitant. The crystals belong to the orthorhombic space group P212121 with unit cell dimensions of a = 54.16 A, b = 79.67 A, and c = 99.48 A and one molecule per asymmetric unit. A complete native data set has been collected to a resolution of 2.1 A, and anomalous dispersion difference Patterson maps have revealed the location of the single heme iron atom. © 1994 Wiley-Liss, Inc.
Practical preparation of some potentially anesthetic fluoroalkanes: regiocontrolled introduction of hydrogen atoms

Abstract Methods are described for the large-scale preparation of a number of fluoroalkanes, which have been tested for general anesthesia.
Infinite horizon stochastic regulation and tracking with the overtaking criterion

This paper considers the standard LQG problem on an infinite horizon with overtaking criterion. A control u*is overtaking optimal if for every other control u there is a time T‘u’ such that Cr‘u∗‘ T‘u’, where Cr‘u’ is the cost over the time interval [0, T] when employing u. We show that the separation principle holds and that the usual stationary optimal control is also optimal in the overtaking sense. We describe certain limiting properties of the optimal controlled process. The relation between overtaking optimal solutions and optimal solutions on finite large intervals is studied
Unobtrusive method for monitoring visual attention during mammogram reading

The use of feedback to the observer of the regions of the image that attract prolonged visual dwell (> 1000 ms) has been shown to improve nodule detection performance in reading chest x-rays. The application of such a feedback mechanism in mammography seems appropriate, but it is often discouraged by the inherent difficulties of using an invasive eye-tracking system. In this paper we discuss the use of an alternative method, namely, a digital zoom window, to monitor where the observer's attention is focused on the image. We have shown that the order in which the zooms occur, as well as the duration of certain zooms, is statistically correlated with decision outcome for a given region of the image. Furthermore we show a strong correlation between zooming and prolonged fixation.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Galaxy Populations in the Fornax and Virgo Clusters

In these first results from a photographic survey of nearby clusters and groups of galaxies, we compare the luminosity functions of galaxies of various Hubble types in the core of the Formax cluster to luminosity functions in the core of the Virgo cluster from Sandageet al. (1985). The galaxy classifications for the two clusters are based on identical plate material, and are hence directly comparable. The properties (galaxy density, velocity dispersion, X-ray luminosity) of the two clusters are quite different, yet we find few significant differences in the luminosity functions, or in the morphological mix of galaxies between the two clusters. In particular, while there is some indication that the ratios of giants to dwarfs and early to late-type galaxies in the two clusters differ, we cannot exclude the possibility that the ratios are identical. We discuss the selection limits of our survey and the completeness corrections that must be applied to the faint end of the luminosity function. The effective surface brightness of early-type galaxies in our sample decreases with decreasing luminosity. We show that this correlation is not an artifact of our selection criteria for dwarf spheroidal galaxies and use it to determine the relative distances to the Fornax and Virgo clusters. We also present evidence for a radial variation in the luminosity function of dwarf ellipticals within the two clusters in the sense that the faint end of the luminosity distribution is enhanced at the centre of each cluster.
Applications of room-temperature tryptophan phosphorescence to the study of protein structure and dynamics

Most proteins are capable of emitting tryptophan phosphorescence at room temperature in deoxygenated aqueous solutions. Like fluorescence, phosphorescence intensities and lifetimes are useful for studying protein structure. Phosphorescence differs from fluorescence, however, in several ways. Phosphorescence occurs on a time-scale of msec-sec, while fluorescence decays in nanoseconds. Second, the phosphorescence decay of a single tryptophan is nearly monoexponential, making assignments of decay components to individual residues possible. Finally, phosphorescence is a more sensitive probe of the local tryptophan environment, as the lifetime can change by orders of magnitude depending on site rigidity and other factors. The authors describe applications of phosphorescence spectroscopy for protein study. In particular, tryptophan phosphorescence quenching by resonance energy transfer to freely diffusing acceptors was used to show that Trp 109 is the origin of phosphorescence in E. coli alkaline phosphatase (AP). By following changes in the emissive lifetime of this deeply buried residue, the presence of an enzymatically active but structurally modified intermediate state is detected in the unfolding of AP in high concentrations of Guanidine:HCl, and followed the kinetics of the decline in activity upon further unfolding. In addition to the new understanding of AP, the results of these experiments show that room temperature tryptophan phosphorescence is a powerful tool for the study of proteins.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Identifying Monetary Impacts on Agricultural Prices in VAR Models

Since the mid-1970s, a number of studies have used vector autoregressive (VAR) models to evaluate the magnitude and timing of macroeconomic impacts on agriculture. Use of the VAR method has been viewed as a way to obtain empirical evidence about these impacts that might not emerge from more traditional overidentified and less dynamic econometric models. The hope has been that by placing minimal restrictions on VAR models, the true structure of the economic relationships under investigation can be observed. While the aim is laudable, critics of VAR models have argued that it has had the unfortunate consequence of obscuring some important structural identification issues and seeming to promise that something can be obtained for nothing (Cooley and Leroy, Leamer). They point out that identifying restrictions are required to give economically interpretable meaning to the results of any simultaneous equation model (SEM). In standard practice, identification of VAR models is obtained implicitly by choice of a Choleski decomposition of the covariance matrix of one-step-ahead forecast errors, which is equivalent to imposing a recursive structure for the economy. Of concern is that the recursive structure may not be believable. Further, as Bernanke has observed, examination of ad hoc variants of the recursive order implies a strange set of prior beliefs in which the analyst holds strongly that the system is recursive but is not sure in what order the variables should be arranged. In response to these concerns, several recent papers have pointed out that identification of VAR models does not have to rely on the assumption that the contemporaneous structure is recursive (Bernanke, Sims). Rather, the distinguishing features of a VAR model are, first, that identification rests on the assumption that distinct, mutually orthogonal behavior shocks drive the economy, and, second, that lagged relationships among the endogenous and exogenous variables (if any) are left entirely unrestricted. Given these features, a VAR model must be identified solely by restrictions placed on the contemporaneous interactions among the variables, but the identifying restrictions do not have to preclude simultaneity. In this paper, we elaborate on the structural interpretation of VAR models and use this analysis to examine monetary impacts on agricultural prices. We discuss the identification problem and the implications of a recursive structure. We illustrate our points with respect to the three-variable model of money, industrial prices, and agricultural prices that has been used in several articles to evaluate the effects of monetary shocks on price dynamics (Bessler, Devadoss and Meyers). We then introduce a somewhat richer behavioral model of the macroeconomy and its effects. A simultaneous model is shown to offer a more believable identification of monetary policy and other macroeconomic shocks than a recursive model, and monetary impacts on agricultural prices are assessed.
Characterization of (111) Gaas and (111) InP substrates and homoepitaxial layers by divergent x-ray beam diffraction

The back-reflection diffraction of a divergent x-ray beam has been studied for the characterization of (111) GaAs and (111) InP substrates and homoepitaxial layers with different states of surface perfection. Diffraction conditions for generating back-reflection pseudo-Kossel patterns from (111) GaAs and (111) InP are presented. Mechanical polishing was observed to produce x-ray diffraction line broadening. Uneven line broadening was found to be produced by an inhomogeneous distribution of dislocations. The diffraction angles for pseudo-Kossel lines were influenced by subgrain tilting in epitaxial, LPE-grown layers. A close relationship between diffraction line profiles and surface morphology of the epitaxial layer was demonstrated with interference-contrast optical microscopy.
Pardacs: a medical data system.

A physiological analog, recording, display, and computing system (PARDACS) is described. The versatihty, accuracy, and stability resulting from wedding medical instrumentation and analog computer components into a compatible system has increased both the amount and quality of data available to our investigators. The system can be shared by several investigators, thus permitting efficient use of equipment, space and technician time. Each investigator can have a patchpanel with the program for his experiment. The setting-up of a new procedure involves insertion of the proper patchboard and adjustment of the attenuators. In addition to ‘on-line’ computation, PARDACS is used in simulation studies and in testing mathematical models. The actual physiological system can be compared with the predicted result from the model with minimal instrumentation problems.