cssi/SciSciGPT-SciSciNet huggingface dataset:
Early detection program for prostate cancer: results and identification of high-risk patient population

Abstract Three hundred sixty-two men underwent transreetal ultrasound of the prostate(TRUS), digital rectal examination (DRE), and serum prostate-specific antigen (PSA) determination as part of an early detection program for prostate cancer. Thirty-seven (10 %) cancers were detected. DRE had the highest sensitivity and specificity, 89 percent and 84 percent, respectively. TRUS and PSA had comparable sensitivities (84 % and 81 %) and specificities (82 % and 82 %). The positive predictive values of DRE, TRUS, and PSA determination were 39 percent, 35 percent, and 33 percent, respectively. We found a cancer detection rate of 16 percent among patients with symptoms of bladder outlet obstruction and 5 percent in patients without these symptoms. The detection rate was 36 percent for physician-referred patients and 3 percent for self-referred patients. This sugests to us that at the present time the best utilization of medical resources to increase prostate cancer detection is to educate men to have annual medical evaluations by primary-care physicians who are encouraged to incorporate risk assessment and screening DRE as part of their routine practice. Any man with either abnormal findings on examination or increased risk should be referred to a urologist for further evaluation.
Self-assembly of acrylic triblock hydrogels by vapor-phase solvent exchange.

We investigate the self-assembly of poly(methyl methacrylate)–poly(methacrylic acid)–poly(methyl methacrylate) triblock copolymers by a vapor-phase solvent-exchange mechanism. Two acrylic triblock copolymers were synthesized with different hydrophilic/hydrophobic block ratios. Hydrogels were formed by exposing the solutions to saturated water vapor. As water diffuses into the solution, the hydrophobic end-blocks form aggregates that are bridged by the hydrophilic mid-blocks. Structure formation in the gels was characterized by small angle X-ray scattering, and swelling was measured in controlled pH buffer solutions. The solvent exchange process occurs while the methacrylic acid group remains in the protonated state. After swelling to equilibrium in water or controlled pH buffers, strong gels are formed with polymer-weight fractions between 0.01 and 0.15, and with shear moduli between 0.6 kPa and 3.5 kPa. Porous gels were produced by adding salt crystals to the polymer solution prior to solvent exchange. Salt was then leached out by immersing the gel into water. Structures of the porous hydrogels were characterized by confocal laser scanning microscopy.
On balanced sets mod p

Abstract Let p be an odd prime, and let a1, a2,…, a2n+1 be elements of Z pZ such that, if any one of them is removed, the remaining ones can be divided into two sets of n elements with equal sums. This paper gives an estimate of the smallest possible size of n, assuming that not all the ai agree.
Interleukin-2 self-association

The self-association of human recombinant interleukin-2 (IL-2) from E. coli was explored. Self-association, with an apparent Kd of 0.6 micromolar, has pronounced effects on (1) the surface exposure of Trp-121, deduced from quenching studies employing potassium iodide and acrylamide, (2) the apparent quantum yield of Trp-121, the fluorescence of Trp-121 in IL-2 aggregates is 4-fold lower than in IL-2 "monomers", and (3) IL-2-mediated phospholipid vesicle fusion/aggregation.
Risk of prostate cancer mortality in men with a history of prior cancer

Objectives To describe outcomes of patients with prostate cancer diagnosed after another malignancy and identify factors associated with prostate cancer death in this population, as little is known about the clinical significance of prostate cancer as a subsequent malignancy. Patients and Methods We studied 18 225 men diagnosed with prostate cancer after another malignancy from 1973 to 2006. We compared demographic and clinical variables, and the proportion of death from prostate cancer vs prior malignancy with t-test and chi-squared analyses. Fine and Gray's regression was used to consider the effect of treatment on prostate cancer death. We then studied a second cohort of 88 013 men with prostate cancer as a first or second malignancy to describe current diagnostic and treatment patterns. Results One in seven men died from prostate cancer in our first cohort. More died from prostate cancer following colorectal cancer (16.8% vs 13.7%), melanoma (13.4% vs 7.56%), and oral cancer (19.1% vs 4.04%), but fewer following bladder cancer, kidney cancer, lung cancer, leukaemia and non-Hodgkin's lymphoma (all P < 0.001). Prostate cancer treatment was associated with a nearly 50% lower risk of death when high-grade or high-stage (adjusted hazard ratio 0.55, 95% confidence interval [CI] 0.47–0.64). Patients who died from prostate cancer had higher grade and stage disease, and received less treatment than patients who died from prior malignancy. The second cohort showed subsequent prostate cancer had more high-risk disease (36.3% vs 22.2%, P < 0.001) and less prostate cancer treatment (adjusted odds ratio 0.872, 95% CI 0.818–0.930) than primary prostate cancer. Conclusions Prostate cancer remains a significant cause of mortality when diagnosed as a subsequent cancer. These results suggest prostate cancer treatment should be seriously considered in patients with prior malignancies, especially those with high-grade or locally advanced prostate cancer.
The kinetics of oxygen exchange between arsenate ions and water. IV. Catalysis by tellurate ions

The oxygen exchange reaction between arsenate ions and water is catalyzed by the addition of a small amount of tellurate ions. The reaction has been studied at 30.0 and 14.5°C over the pH range of 6.5–11.4. The rate law of catalytic reaction has been found to be Rc = k[As(V)]n[Te(VI)], where Rc is defined as the increase in the rate of oxygen exchange of arsenate ions by the addition of tellurate ions, and n has a value of 0.8–1.0 depending on the value of pH. The catalytic process has been interpreted in terms of the reversible condensation of arsenate ions with tellurate ions to form the arsenatotellurate ions, and the rate constant of the condensation reaction between HAsO42− and H5TeO6−has been estimated to be 0.22 mol dm−3 at 30°C.
Motivating knowledge workers to innovate: a model integrating motivation dynamics and antecedents

Grounding in the premise that motivation in a knowledge work environment is an outcome of the existence of certain antecedents that are responsive to the dynamics of motivation in this environment, this work develops a conceptual model synthesizing motivations “what” and “how” that will bring human creativity in organizations which thrive on innovation. The presented model embodies these dynamics into five drivers of motivation practice in the knowledge work environment and then leads to three sources of motivation into which its antecedents should be loaded to motivate knowledge employees for innovation.
Sound Objects and Sound Products: Standardizing a New Culture of Listening in the First Half of the Twentieth Century

In this chapter I develop the psychological underpinnings of environmental music towards an understanding of how the goals of cognitive and behavioral psychologists contributed to a new kind of listening at the beginning of the twentieth century. I begin with an examination of nineteenth-century concerns about both the physical and psychological effects of music and fraught debate among experimental psychologists of the role of musical expertise in the laboratory. These concerns were, I argue, rooted in the assumption of a direct, corporeal connection between the generation and reception of music, usually bound within a single, individual body. In the twentieth century, new technology liberated the listener from a temporally- and geographically-bound experience of music. The Tone Tests, Re-Creation Recitals, and Mood Change “parties” of Thomas Edison and the psychologist Walter Bingham show that recording technology allowed for a normalization and standardization of listening not previously possible in the music halls and laboratories of the nineteenth century. Rather paradoxically, since it also made music more accessible to the individual listener, recorded music, mobilized by industrial psychologists and record companies alike, created a new sound experience actively designed for the lowest common denominator of mass listening. It also contributed to the cultivation of a new practice of mass listening. The new mass listening practice presents broader questions about the definition of music and its functional role – If the function of music is to be ignored, is it still music?
Concurrent Criterion-Related Validity of Early Literacy Indicators for Middle of First Grade.

The purpose of this study was to examine the concurrent criterion-related (or convergent) validity of first grade measures from the Dynamic Indicators of Basic Early Literacy Skills (DIBELS; Good &...
Fostering Equitable Consequences from Computer Learning Environments.

This article discusses (a) the potential advantages of learning computer programming, (b) the performance of males and females in middle school programming courses, (c) the problems teachers face in achieving this potential, and (d) the participation of males and females in programming courses. Females comprise about 40% of the students enrolled in middle school programming courses. They perform, on the average, as well as or better than the males, and comprise 60% of the most talented students. Significantly, neither males nor females make very much progress in learning to program and, therefore, in acquiring any of the general cognitive skills which might potentially result from programming courses.
Electronic Interactions in Iron- and Ruthenium-Containing Heterobimetallic Complexes: Structural and Spectroscopic Investigations

The heterobimetallic Ru complexes Cp(CO)Ru(μ-I)(μ-dppm)PtI2 (8), Cp(CO)Ru(μ-I)(μ-dppm)PdI2 (10), and Cp(CO)RuI(μ-dppm)AuI (12) and their isoelectronic Fe analogues Cp(CO)Fe(μ-I)(μ-dppm)PtI2 (9), Cp...
The fluorocarbon-ozone theory—VI. Atmospheric modeling: Calculation of the diurnal steady state

Abstract In the recent past there has been a general effort to develop one-dimensional models of stratospheric transport and photochemistry which include the effects of Rayleigh scattering of the solar radiation and diurnal changes in the solar zenith angle. Direct integration of the diurnal problem is so expensive and time consuming that it cannot be generally applied. It is therefore necessary to seek other numerical approaches which will allow accurate diurnal averaging while retaining most of the features of the more sophisticated 24 h average models. In the present paper we describe an approach to the diurnal problem which includes all of the important features of conventional one-dimensional models (Rayleigh scattering, diffusion of all species, updating of photolytic rate constants, etc.) and, at the same time gives an accurate diurnal steady state and accurate diurnal steady ozone perturbations with modest computation times. It is shown that the “diurnal correction” prior to recent redeterminations of the rate constant for the reaction HO 2 + NO → OH + NO 2 was 70%. With the inclusion of the new rate information the “diurnal correction” is 30%. The ozone depletion calculated for steady state fluorocarbon release at 1975 levels, with the assumptions outlined in this paper are 7.9% and 14.2% for the old and new HO 2 + NO rates respectively.
“Scratching” beneath the surface: An integrative psychosocial approach to pediatric pruritus and pain:

Pruritus is prevalent in children with atopic dermatitis and associated with effects on mood, quality of life, sleep, scholastic performance, social and family functioning. In this study a 7-year-o...
DOES THYROPARATHYROIDECTOMY IN THE DOG AFFECT THE BLOOD COAGULATION TIME

In the dog the blood-coagulation time varies considerably in different individuals, and in the same individual from time to time. The tetany resulting from the removal of the thyroid and all the parathyroid glands does not appear to have any distinct effect on the coagulability of the blood. This applies also to the period before the onset of tetany and to that immediately succeeding it. In our experience the venosity of the blood does not seem to affect the coagulation time in the dog.
A correlation between voluntary ethanol consumption and brain catalase activity in the rat

Abstract The relationship between voluntary ethanol consumption and brain catalase activity was investigated in male Long Evans rats. In the first study, rats which were voluntarily consuming alcohol or water for 25 days were sacrificed by decapitation immediately (group A) or 15 days (group B) following withdrawal of alcohol and their brains analysed for catalase activity. Mean brain catalase activity did not differ among the two groups of rats exposed to ethanol and the ones exposed to water only. Furthermore, there were significant positive correlations between individual voluntary ethanol intake and catalase activity in both groups, (group A:r=.69, p ≤0.05; group B:r=.54, p ≤0.05). In a second study, rats were forced to drink high levels of ethanol presented as the only source of fluid for 25 days. Rats were sacrificed and brain, liver, muscle and heart tissue were extracted and analysed for catalase activity. There were no differences in mean brain catalase activity between water and forced ethanol drinking rats indicating that the enzyme was not inducible by high volume ethanol consumption. The results suggest that inherent differences in brain catalase activity may be one of the factors in determining an animal's propensity to voluntarily consume ethanol.
Can machines be conscious

Would you sell your soul on eBay? Right now, of course, you can't. But in some quarters it is taken for granted that within a generation, human beings-including you, if you can hang on for another 30 years or so-will have an alternative to death: being a ghost in a machine. You'll be able to upload your mind-your thoughts, memories, and personality-to a computer. And once you've reduced your consciousness to patterns of electrons, others will be able to copy it, edit it, sell it, or pirate it. It might be bundled with other electronic minds. And, of course, it could be deleted.
An empirical validation of complexity profile graph

This paper presents the results of an empirical study carried out to investigate if the complexity profile graph (CPG) is related with one of the predicators of software complexity measures, such as response time and error rate, and thus could be used as a valid indicator of program comprehensibility. Lower and upper division computer science and software engineering students were asked to respond to questions regarding the execution of a source code module written in JAVA and understanding the fundamental goal of each part of the source code. The response time for each question and the correctness of each response were recorded. The statistical analysis of the experimental data reports that there is a positive linear correlation between the CPG and the time taken to respond correctly to each question. In addition, the paper discusses if there is any effect of the control structure diagram (CSD) on measuring the difficulty of program comprehensibility.
Solutions to Gate Oxide Integrity on TFSOI Substrates Caused by PMOS Threshold-Voltage Implant

Due to the lack of effective gettering, gate oxide on thin-film-silicon-on-insulator (TFSOI) substrates is much more sensitive than its bulk Si counterpart to process damage during device fabrication, especially prior to gate oxide growth. Presented in this paper as a typical example is the severe oxide degradation caused by PMOS threshold-voltage implant. Several approaches to circumvent this problem are explored, such as Vt implant without sacrificial oxide (sacox), low temperature anneal before sacox removal, or implementation of lateral gettering. As a result of these efforts, a significant improvement in gate oxide integrity is achieved with increased oxide breakdown voltages and charge-to-breakdowns, as well as a reduction in oxide charge trapping. This work also demonstrates the feasibility of achieving bulk-comparable gate oxide on TFSOI substrates.
Studies on avian erythrocyte metabolism—X. Purification and properties of phosphoglyceromutase from erythrocytes of day-old chicks

Abstract 1. 1. The purification of phosphoglyceromutase from erythrocytes of day-old chicks is described. 2. 2. The purified enzyme migrates as a single band when electrophoresed on polyacrylamide gel containing sodium dodecyl sulphate, β-mercaptoethanol and urea. Its estimated subunit molecular weight is 26,500 daltons. 3. 3. The enzyme possessed no mutase activity in the absence of 2,3-diphosphoglycerate (2,3-DPG). Its K m for 3-phosphoglycerate is 6.6 × 10 −4 M and for 2,3-DPG is 8 × 10 −6 M. The enzyme exhibited 2,3-DPG phosphatase activity in the presence of 2-phosphoglycolate or pyrophosphate. These kinetic properties are identical to those of the phosphoglyceromutases of the erythrocytes of man and goat reported earlier from this laboratory. 4. 4. In contrast to the activity of 2,3-diphosphoglycerate phosphatase-mutase, the phosphoglyceromutase activity in the erythrocytes did not vary in the embryo or chick from that in the adult bird.
The optimal control of some attitude control systems for different performance criteria

Pontryagin maximum principle to optimize attitude control systems on the basis of minimum fuel or energy consumption
Intercalative G-Tetraplex Stabilization of Telomeric DNA by a Cationic Porphyrin1

DNA tetraplex (“quadruplex”) structures formed from guanine tetrads and significant to the regulation of telomerase activity have recently been shown to be stabilized by interaction with a cationic porphyrin [Anantha, N. V.; Azam, M.; Sheardy, R. D. Biochemistry 1998, 37, 2709−2714. Wheelhouse, R. T.; Sun, D.; Han, H.; Han, F. X.; Hurley, L. H. J. Am. Chem. Soc. 1998, 120, 3261−3262]. Porphyrin binding to DNA sequences from the Oxytricha and human telomeres and a thrombin-binding aptamer is here examined by isothermal titration calorimetry (ITC) and spectrophotometry under conditions that favor self-assembly to their respective intermolecular or intramolecular tetraplex structures. Analysis of the ITC and optical data reveals (i) saturating porphyrin/tetraplex binding stoichiometries of 1:1, 2:1, and 3:1 for d(G2T2G2TGTG2T2G2), d(AG3[T2AG3]3), and [d(T4G4)]4, respectively, involving near-equivalent sites, (ii) weak binding of only (0.3−2) × 105 M-1 per site, and (iii) no evidence for stepwise complexation...
Work and Resources Needed for Endoscopic Resection of Large Sessile Colorectal Polyps

Background & Aims: Large sessile colon polyps often are referred for surgical resection, even when amenable to endoscopic resection. The aim of this study was to describe the resource use of endoscopic resection of large sessile colon polyps compared with small polyps with respect to physician time and equipment use. Methods: Retrospectively, procedure time, medication use, and equipment use were recorded for 184 consecutive patients with sessile colorectal polyps 2 cm or larger in size and for 184 consecutive control patients with only sessile polyps less than 2 cm in size or pedunculated polyps. Results: The mean duration of colonoscopy in patients with large sessile colon polyps averaged 51.4 (SD, 25.6) minutes compared with 20.0 (SD, 8.6) minutes for the control group ( P P Conclusions: Our results indicate that the costs of endoscopic large sessile adenoma resection in physician work and equipment are substantially greater than the costs of resection of small adenomas. These costs may be a deterrent to endoscopic resection of large sessile adenomas and may warrant increased reimbursement for those procedures, particularly if predictions that colonoscopic procedures will become more complex in the future are realized.
The black-market exchange rate and currency substitution in a small open economy: An empirical analysis of Barbados

Abstract Empirical evidence of the existence of currency substitution in Barbados between 1973 and 1986 is provided. Within an environment of trade restriction, foreign exchange control, and a black market for foreign exchange, the demand for money is estimated using the black-market premium as one of the independent variables. This variable as a proxy measures the opportunity cost of holding domestic money vis-a-vis foreign money, and its statistical significance indicates the existence of currency substitution in the demand for only M1, which could render stabilization policies ineffective.
HLA Associations in Heroin-Associated Nephropathy

Heroin-associated nephropathy (HAN) occurs almost exclusively in black heroin abusers, suggesting a genetic link to the disease. To further study this possibility, the frequencies of HLA-A, B, C, and DR antigens were determined in a group of 47 black patients with HAN. Included in the analyses is a subgroup of 16 patients with biopsyproven focal glomerulosclerosis. Patient frequencies were compared with three separate control populations, the first a normal black population from New York City, the second from a national registry, and the third a group of blacks with idiopathic focal glomerulosclerosis. Only the frequency of HLA-BW53 was consistently increased significantly in the patients as compared with the control groups. This finding supports the notion that a genetic predisposition may exist in the addicted population for the development of renal disease.
Applied Mathematical Problem Solving.

A case is presented for the importance of focusing on (1) average ability students, (2) substantive mathematical content, (3) real problems, and (4) realistic settings and solution procedures for research in problem solving. It is suggested that effective instructional techniques for teaching applied mathematical problem solving resembles “mathematical laboratory” activities, done in small group problem solving settings. The best of these laboratory activities make it possible to concretize and externalize the processes that are linked to important conceptual models, by promoting interaction with concrete materials (or lower-order ideas) and interaction with other people. Suggestions are given about ways to modify existing applied problem solving materials so they will better suit the needs of researchers and teachers.
The giant resin bee making its way west: First record in Kansas (Hymenoptera: Megachilidae)

Th e invasive giant resin bee (Megachile sculpturalis Smith) was fi rst discovered in North America in 1994. A 2005 study provided the fi rst predictive ecological niche model for any bee species and concluded that M. sculpturalis, then confi ned to the eastern United States, would eventually spread as far south as southern Florida, as far north as southern Ontario and Nova Scotia, and as far west as South Dakota, western Kansas, and northwestern Texas. Herein I provide the fi rst record of M. sculpturalis from northeastern Kansas, documenting that the species has indeed continued its westward expansion in North America and the new available records entirely correspond to the earlier predictions.
Charge-Separation in Uranium Diazomethane Complexes Leading to C−H Activation and Chemical Transformation

The reaction of diphenyldiazomethane with [((t-BuArO)3tacn)UIII] (1) results in an η2-bound diphenyldiazomethane uranium complex. This complex exhibits unusual electronic properties as a charge-separated species with a radical anionic open-shell ligand, [((t-BuArO)3tacn)UIV(η2-NNCPh2)] (2). Treating Ph2CN2 with a uranium complex that contains a sterically more demanding adamantane functionalized ligand, [((AdArO)3tacn)UIII] (3) results in an unprecedented C−H activation and nitrogen insertion to produce a five-membered heterocyclic indazole complex, [((AdArO)3tacn)UIV(η2-3-phen(Ind))] (5). X-ray crystallography and spectroscopic characterization of these two compounds show that the [((t-BuArO)3tacn)UIV(η2-NNCPh2)] compound is a U(IV) complex with a radical anionic ligand, whereas [((AdArO)3tacn)UIV(η2-3-phen(Ind))] is a U(IV) f 2 species with a closed-shell ligand.
Extraskeletal spread in multiple plasma cell myeloma. A review of 57 autopsied cases.

This study analyzes the extraskeletal spread in 57 consecutively autopsied cases of multiple myeloma. Three stages of spread were recognized: stage I in which myeloma nodules were grossly confined to the skeleton; stage II with extraskeletal spread grossly confined to adjoining paraskeletal tissues; stage III with gross spread to distant sites. Extraskeletal gross or microscopic myeloma infiltrates were present in 65% of cases in this series. In stage I, microscopic infiltrates were found in 34% of cases. In addition to the gross lesions seen in stage III, all stage II and III cases showed distant microscopic tumor infiltrates. The commonest sites of these were the spleen, liver, lymph nodes and kidneys. Patients with the longest duration of illness tended to have the most widespread extramedullary involvement. Patients dying with stage III lesions tended to have a higher proportion of poorly differentiated tumor as compared to patients with stage I and II. Because of evidence of intravascular and “linear” spread in paravertebral connective tissues and because of involvement of sites other than lymphoreticular organs, it is difficult to escape the conclusion that extraskeletal sites in myeloma represent true metastases rather than autochthonous multifocal growths.
Meta-Analysis of Rare Binary Adverse Event Data

We examine the use of fixed-effects and random-effects moment-based meta-analytic methods for analysis of binary adverse-event data. Special attention is paid to the case of rare adverse events that are commonly encountered in routine practice. We study estimation of model parameters and between-study heterogeneity. In addition, we examine traditional approaches to hypothesis testing of the average treatment effect and detection of the heterogeneity of treatment effect across studies. We derive three new methods, a simple (unweighted) average treatment effect estimator, a new heterogeneity estimator, and a parametric bootstrapping test for heterogeneity. We then study the statistical properties of both the traditional and the new methods via simulation. We find that in general, moment-based estimators of combined treatment effects and heterogeneity are biased and the degree of bias is proportional to the rarity of the event under study. The new methods eliminate much, but not all, of this bias. The variou...
The Reaction of Quaternary Ammonium Salts Derived From 2 Aryl-3-(N,N-dimethylamino)-1-propenes with Some Enoiate Anions

Abstract A variety of quaternary ammonium salts derived from 2-aryl-3-(N,N-dimethylamino)-1-propenes have been reacted with enolate anions derived from several activated methylene compounds. The reactions represent clean and efficient methodology for the elaboration of the 2-aryl-1-propene system.
Electronic motion in a model solid of short range potentials

Abstract The motion of an electron moving in a model solid which consists of an array of very short range scatterers is considered. This system introduces simplifications because the detailed nature of the individual scatterers enters in only a very simple fashion. The theory is developed for an arbitrary array of short range potentials and is then specialized to a periodic system. (Both infinite and semiinfinite [surface] cases are discussed.) The case of a system of periodically positioned scatterers, the inexactly known strengths of which are described by a Lorentzian distribution, is also considered. Finally, the theory is applied to the case of an electron, under the influence of a rational magnetic field, moving amid a periodic array of short range potentials.
Social Tension Indexes and Egg Production Traits in Chickens

Abstract CORRELATIONS between peck-order ranks of individual hens in flocks and various production traits have been reported (Sanctuary, 1932; Guhl, 1953; McBride, 1958; and Tindell and Craig, 1959). Peck orders become difficult to establish as flock size (N) increases, as there are N(N-1)/2 pair relationships involved. Determination of peck-order rank may be impossible in large groups of hens because of territorial behavior (McBride and Foenander, 1962; and Craig and Guhl, 1969). “Dominance ratios” (number of agonistic interactions dominated)/(total agonistic interactions) times 100, and “social tension indexes” (number of aggressive minus number of submissive acts) both have been used to characterize agonistic behavior of individual pullets in flocks by Craig and Guhl (1969) and by Craig et al. (1969), respectively. These estimators appear suitable for use in large flocks as they may be determined without working out the peck order. Social tension indexes appear preferable to dominance ratios from the statistical…
An unprecedented tetrahedral zinc mutual-face-insertion coordination polymer with both covalent and double-hydrogen bonding interactions

A tetrahedral zinc coordination polymer with a novel mutual-face-insertion double-layer structure has been synthesized, and characterized by single crystal X-ray diffraction. The mutual-face-insertion created anisotropic interactions between the layers. The separation between the double layers in the structure is about 3.5 A. The framework structure is stable up to 307 °C.
Alkali promoters on supported nickel: Effect of support, preparation, and alkali concentration

Abstract The effect of potassium promoter for CO hydrogenation on supported nickel catalysts was studied in a differential reactor. The influences of the support (SiO2, SiO2 · A12O3), the promoter concentration (0.05–4% K), the alkali salt (KC1, K2CO3, K2C2O4, KOH, KNO3), and the method of preparation (pre- and coimpregnation, and calcination) were studied. The activity and selectivity of promoted catalysts are shown to depend on the support; modifications in catalytic properties are not just due to a KNi interaction. On Ni SiO 2 an exponential decrease in total activity with increased promoter concentration is seen; this decrease is not due to a decrease in percentage nickel exposed (dispersion). A large increase in olefin/paraffin ratios is seen on Ni SiO 2 as the promoter decreases hydrogenation rates. In contrast, on Ni SiO 2 · A12O3, the rate of paraffin formation, including methane, increases and exhibits a maximum with increased promoter concentration. Olefin selectivities decrease and higher paraffin selectivities increase. Much of the potassium salt may react with the silica-alumina support to modify the catalytic properties. The method of preparation has a lesser influence on the catalyst than the potassium concentration. The use of different potassium salts resulted in similar catalytic properties, indicating that for a given support the same potassium compound formed during preparation. A good correlation was found between C2 and C3 olefin/paraffin ratios and inverse total activity, showing that olefin selectivities increase as hydrogenation rates decrease.
Mapping playa evaporite minerals with AVIRIS data: a first report from Death Valley, California

The feasibility of using imaging spectrometry in studies of playa evaporites is demonstrated by mapping efflorescent salt crusts in Death Valley (California), using Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data and a recently developed least-squares spectral band-fitting algorithm. It is shown that it was possible to remotely identify eight different saline minerals, including three borates that have not been previously reported for the Death Valley efflorescent crusts: hydroboracite, pinnoite, and rivadavite. The three borates are locally important phases in the crusts; at least one of them, rivadavite, appears to be forming directly from brine.
Micro-Cathode Arc Thruster for small sattelites attitude control

A low-mass, low-volume propulsion subsystems based on electrically activated micro-thrusters that utilize chemically-inert solid propellants are beneficial for small satellite attitude control applications. Micro-thrusters are able to deliver small impulse bits of about several µNs to satellites and characterized by simplicity, scalability, low cost, low weight and high reliability. In this work measurements of the key parameters of micro-Cathode Arc Thruster (µCAT) are presented and µCAT performance compared with other commercially available thruster technologies operating at the same power range.
Polar rain aurora

[1] Global FUV auroral imagers (IMAGE/SI-13 and DMSP/SSUSI) observed, for the first time, two similar auroral events in the southern polar cap due to intense (keV) polar rain electrons from the solar wind as observed by DMSP and Geotail. Such an aurora is called polar rain aurora. The polar rain aurora could fill the dayside polar cap initially and developed a dawn-dusk alignment while they moved anti-sunward. The associated IMF Bz was mostly southward. The IMF Bx changed from negative to positive for the first event and stayed positive for the second event. The strong IMF By was associated with the two events. The dawn-dusk alignment of polar rain aurora might be due to the dawn-dusk aligned magnetic flux tubes in the magnetosheath caused by the dominant IMF By and modulation of the keV electrons by the nonoscillatory drift mirror waves and pitch angle diffusion via the electron cyclotron instability.
Millennials and the World of Work: An Economist's Perspective

This article uses an economic approach to address whether and how the Millennial generation is significantly different from its predecessors. Particular attention is paid to the normal life cycle stages through which all generations pass, and the implications for forecasting how the Millennials’ relationship with the world of work will evolve. A second key issue is the extremely large differences in economic opportunity that exist among the members of each generation, and which have increased for more recent generations, particularly those with lower levels of education. Other key issues include the rise in international competition for jobs, and the rising cost of a college education. These factors together imply that simple stereotypes about Millennials taking a privileged view of the world of work may be simplistic at best, and likely are significantly off target.
Risk perception and effectiveness of uncoordinated behavioral responses in an emerging epidemic.

Abstract Beyond control measures imposed by public authorities, human behavioral changes can be triggered by uncoordinated responses driven by the risk perception of an emerging epidemic. In order to account for spontaneous social distancing, a model based on an evolutionary game theory framework is here proposed. Behavioral changes are modeled through an imitation process in which the convenience of different behaviors depends on the perceived prevalence of infections. Effects of misperception of risk induced by partial or incorrect information concerning the state of the epidemic are considered as well. Our findings highlight that, if the perceived risk associated to an epidemic is sufficiently large, then even a small reduction in the number of potentially infectious contacts (as a response to the epidemic) can remarkably affect the infection spread. In particular, the earlier the warning about the epidemic appears, the larger the possible reduction of the peak prevalence, and of the final epidemic size. Moreover, the epidemic spread is delayed if individuals’ perception of risk is based on a memory mechanism and the risk of infection is initially overestimated. In conclusion, this analysis allows noteworthy inferences about the role of risk perception and the effectiveness of spontaneous behavioral changes during an emerging epidemic.
Serum carnosinase deficiency concomitant with mental retardation.

Extract: A family was studied in which two boys with progressive neurologic disease exhibited carnosinemia (20–30 μUmol/ml serum), carnosinuria (60–200 μUmol/24 hr), and a deficiency in serum carnosinase activity (<0.03 μUmol/hr/ml). Their sister, who is apparently both physically and mentally normal, also exhibits carnosinuria and is deficient in serum carnosinase activity. Tissue extracts of liver, kidney, and spleen obtained at autopsy of one of the male patients were assayed for carnosinase and other enzyme activities and were subjected to starch block electrophoresis at pH 7.0 for 4 hr at 4°. The starch block electrophoreses, under conditions which readily demonstrate two electrophoretic forms of the enzyme in normal tissue extracts, revealed that only one of the two forms was present. This activity corresponded to the slower form in normal tissues and appeared to be present in normal concentrations. Speculation: The excretion of abnormal quantities of carnosine and/or anserine in the urine appears to be related to inherited serum carnosinase deficiency, but further studies are required to determine the association of the deficiency of the enzyme with progressive neurologic disease as well as the nature and role of the two electrophoretic forms of tissue carnosinase activity.
The sieving of rod-shaped viruses during agarose gel electrophoresis. I. Comparison with the sieving of spheres

The sieving of rod-shaped viruses during agarose gel electrophoresis is quantitatively analyzed here with a previously proposed model [G. A. Griess et al. (1989) Biopolymers, 28, 1475-1484] that has one radius (PE) of the effective pore at each concentration of gel. By use of this model and an internal spherical size standard, a plot of electrophoretic mobility vs agarose percentage is converted to a plot of the radius of the effective sphere (effective radius) vs PE. Experimentally, when the concentration of the rod-shaped bacteriophage, fd, is progressively increased, eventually the electrophoretic mobility of fd becomes dependent on its concentration. The concentration of fd at which this occurs decreases as the agarose concentration decreases. After avoiding this dependence on the concentration of sample, the effective radius of rod-shaped particles, including bacteriophage fd, length variants of fd, and length variants of tobacco mosaic virus, is found to increase as PE increases until a plateau of approximately constant maximum effective radius is reached at PcE. In the region of this plateau, the effective sphere's measure that best approximates that of the rod is surface area. However, significant disagreement with the data exists for surface area; the maximum effective radius for fd varies as (length)0.69. For fd and its length variants, the value of 2.PcE/length increases from 0.21 to 0.86 as the length decreases from 2808 to 367 nm. The dependence of effective radius on PE and the proximity of 2.PcE to the length of the rod are explained by (a) random orientation of rods at PE values in the region of the plateau, and (b) increasingly preferential end-first orientation (reptation) of the rod as PE decreases below PcE. This hypothesis of reptation is supported by a significant dependence of electrophoretic mobility on electrical potential gradient for a PE below, but not above, PcE. The dependence of 2.PcE/length on length is not rigorously understood, but is qualitatively explained by flexibility of the rods. This apparent flexibility has thus far prevented determination of a rod's axial ratio from quantitation of sieving during agarose gel electrophoresis. The electrical potential dependence of electrophoretic mobility is determined here by a procedure of two-dimensional agarose gel electrophoresis. This procedure is also useful for detecting rod-shaped particles in heterogeneous mixtures of predominantly spherical particles.
Autonomic Dysfunction in Subacute Spongiform Encephalopathy

• Autonomic nervous system functions were studied in two patients with subacute spongiform encephalopathy (SSE) and compared with those of four patients with presenile dementia—Huntington's disease and Alzheimer's disease. Autonomic dysfunctions in patients with SSE included the following: diminished lacrimation; abnormal pupillary responses to topically applied autonomic drugs; subnormal pulse rate in response to the cold face test and atropine administration; anhidrosis and absence of a rise in blood pressure in response to the cold pressor test. These functions were normal in dementia patients who served as controls. Postmortem studies disclosed morphologic alterations in the sympathetic ganglia and vagus nerve.
Review: low-molecular-weight heparin is better than unfractionated heparin to prevent VTE after ischemic stroke.

Source Citation Shorr AF, Jackson WL, Sherner JH, Moores LK. Differences between low-molecular-weight and unfractionated heparin for venous thromboembolism prevention following ischemic stroke: a m...
Expression of hair-related keratins in a soft epithelium: Subpopulations of human and mouse dorsal tongue keratinocytes express keratin markers for hair-, skin- and esophageal-types of differentiation

Abstract The dorsal surfaces of mammalian tongues are covered with numerous projections known as filiform papillae whose morphology varies in different species. Using a panel of monoclonal antibodies to keratins as probes, we have established that, in both human and mouse, the interpapillary epithelia express mainly the “esophageal-type” keratins, while the papillary epithelia express “skin-type” keratins as well as some keratins reacting with a monoclonal antibody (AE13) to hair keratins. The AE13-reactive proteins of the mouse were found to be very similar to those of authentic mouse hair keratins. However, the corresponding protein of human tongue appears to be different from all known human keratins. This protein has a MW of 51K; it is relatively acidic; it is sulfhydryl-rich, as revealed by iodoacetic acid-induced charge and apparent size shift; it shares an epitope with all the known acidic human hair keratins; and it is associated with keratin fibrils in vivo . This protein may therefore be regarded as a novel type I “hard” keratin. These data establish that mammalian dorsal tongue epithelia can be divided into at least three compartments that undergo mainly “esophageal-”, “skin-” and “hair”-types of differentiation. Different keratin filaments, e.g., those of the esophageal- and hair-types, exhibit strikingly different degrees of lateral aggregation, which can potentially account for the different physical strength and rigidity of various cellular compartments. Our data also suggest the possibility that variations in papillary structure in human and mouse may arise from different spatial arrangements of specific keratinocytes, and/or from the expression of specialized hair-related keratins.
Postnatal growth and neuropsychological performance in preterm-birth preschoolers.

OBJECTIVE Compromised postnatal growth is an important risk factor accounting for poorer neuropsychological performance of preterm children during the preschool years, yet its unique contribution to explaining outcome variance within this high risk group has yet to be determined. Therefore, we examined within a large preterm sample (1) the relationships between head growth, measured either at birth or preschool age, and outcome; (2) the relationships of binary versus dimensional head growth measures and performance; and (3) the unique contribution of preschool-age head growth, after adjustment for general physical development (indexed by stature), to variance in neuropsychological functioning. METHOD We evaluated 264 preterm (<36 weeks) preschoolers, without severe handicaps, using cognitive, language, and motor skill measures. Multiple regression analyses, adjusting for sociodemographic factors and pre-, peri-, and postnatal confounds, were used to study associations between growth indices and performance. RESULTS While suboptimal head growth classification at birth was significantly associated only with motor performance, suboptimal head growth at preschool age explained a significant portion of variance in intellectual and language measures (g = .46 to .60). Treating preschool head size as a continuous dimension yielded null results, however, with body-height explaining a significant portion of the variance across several domains. CONCLUSION Among postnatal anthropometric indices, preschool stature, rather than head circumference, remains a consistent correlate of preschool outcome in preterm children, highlighting the contribution of general physical development to neuropsychological performance. Further investigation of the underlying mechanisms likely involves exploration of complex relationships between postnatal nutrition, growth hormone levels, body and brain development, and neuropsychological functioning.
P16-36. Functional genomic immune profile of SIV DNA vaccines delivered by electroporation and combined with molecular adjuvants

Background There are a number of challenges in the development of an effective vaccine for HIV, including stimulation of potent and broad cellular and humoral immune response that can cross protect between strains or clades. We have studied the cellular immune response, using genomics, of a DNA based vaccine that resulted in potent and broad cellular immune responses that suppressed SIV251 replication.
T4 replication: What does “processivity” really mean?

DNA polymerases are full of surprises. It is widely accepted that replicative polymerases are highly processive, thanks, in large part, to accessory subunits that act as sliding clamps and tether the polymerase to its DNA template. The bacteriophage T4 replication system is typical in that processivity measurements indicate that a substantial fraction of replication complexes should remain associated with DNA for the ≈15 min required to copy an entire genome length (1). However, an elegant study by Yang et al . (2) in this issue of PNAS challenges our notion of processivity by showing that, within the highly processive T4 replisome, individual DNA polymerase molecules are exchanging rapidly, maybe 90 times per genome length under the conditions prevailing in vivo . Thus, if the replisome is visualized as a molecular factory, the workers are making frequent shift changes. The bacteriophage T4 replisome, on which these studies were carried out, serves as a simple model incorporating the essential features of multisubunit replication systems. The components of the T4 system are illustrated in cartoon form in Fig. 1. The high overall processivity of the replisome does not necessarily mean that all subunits are equally processive, and two approaches have been informative in measuring the life-times of individual components within an actively synthesizing replisome. The simplest is to determine the sensitivity of DNA synthesis to dilution of individual components. This approach has demonstrated that the helicase (gp41) is very stably associated with the replication fork (1). By contrast, lagging strand synthesis was sensitive to dilution of the clamp (gp45), clamp loader (gp44/62 complex), and primase (gp61) (5, 6), reflecting the remodeling of the lagging strand machinery that must take place as each new Okazaki fragment is started. Significantly, dilution of the polymerase (gp43) did not affect lagging strand synthesis, implying that …