cssi/SciSciGPT-SciSciNet huggingface dataset:
4.06 – Alcohol Dehydrogenases

The family of mammalian alcohol dehydrogenases (ADHs) is widely expressed, and catalyzes the oxidation and reduction of many different alcohols and aldehydes. They have overlapping distributions in different tissues, as well as overlapping substrate specificities, and play a key role in metabolism of substrates such as ethanol, retinol, and formaldehyde, among many others. Variations in the structure and expression of these enzymes are associated with differences in risk for alcoholism and for alcohol-related organ damage, including cancer. This chapter reviews the structure, regulation, and substrate specificity of these enzymes and their potential roles in pharmacogenetics and disease.
Quantitative Resistance Assessment of SFRP-Strengthened RC Bridge Columns Subjected to Blast Loads

AbstractThe blast resistance of a typical reinforced concrete bridge pier column design was modeled with a nonlinear finite element approach that considers material damage, fracture, and separation...
Provider Advice and Patient Perceptions on Weight Across Five Health Systems

Introduction To improve the management of overweight and obesity in the primary care setting, an analysis of patient perceptions of weight status and predictors of weight loss attempts for those with overweight and obesity is needed. Methods Primary care patients (n=949) across 5 health systems in the Mid-Atlantic region of the U.S. were surveyed in 2015; data analysis was performed in 2018. Survey data was combined with data via the electronic health record to understand patients’ perceptions of weight, factors associated with weight loss efforts, and provider counseling practices. Results Most participants with overweight or obesity perceived themselves as weighing too much and reported trying to lose weight. Furthermore, most participants with obesity reported receiving advice to lose weight by a provider in the past 12 months. However, less than half of patients with overweight reported receiving advice to lose weight, maintain weight, or develop healthy eating and physical activity patterns from a health professional in the past 12 months. Among participants with overweight and obesity, multivariable logistic regression analysis demonstrated that the perception of being overweight and receiving healthcare advice to lose weight had the highest odds of reporting attempted weight loss (OR=5.5, 95% CI=2.7, 11.2 and OR=3.9, 95% CI=1.9, 7.9, respectively). Conclusions The findings emphasize the importance of provider attention to weight management counseling and identifies patients with overweight as needing increased attention by providers.
Female Lower Urinary Tract Symptom Prevention and Treatment Strategies on Social Media: Mixed Correlation With Evidence.

Abstract Objective To evaluate the level of evidence behind recommendations on social media for disease prevention in five lower urinary tract symptoms. Materials and Methods We conducted a digital analysis of anonymous online posts on social media sites collected by a social media data mining service. One thousand posts about pelvic organ prolapse, stress urinary incontinence, overactive bladder, urinary tract infection, and interstitial cystitis/bladder pain syndrome were randomly selected. We analyzed these posts for recommendations regarding the prevention and treatment of these diseases, which were then compared to recommendations in available clinical guidelines and assessed for level of evidence. Results A total of 158 of 1000 posts contained 239 prevention strategies. For pelvic organ prolapse, there were 41 strategies identified, 25 (61%) of which had no evidence. For urinary tract infection 14 of 58 (29%) had no evidence, including recommendations for dietary modifications and urinary alkalization. For overactive bladder 8 of 28 (29%) had level 4 or no evidence. For stress urinary incontinence, 12 of 34 (36%) of prevention strategies had no evidence, such as laser rejuvenation and bladder training. Interstitial cystitis had the highest number of prevention strategies, and most were low or nonevidence based (70/79, 89%). Conclusion Prevention and treatment strategies are common in online discussions of pelvic floor disorders, but at least one third of these recommendations have no evidential support. There is a role for further online education and social media engagement by health care specialists to promote evidence-based practices.
Blood-Based Biomarkers for Predicting Immunotherapy Benefit in Lung Cancer

PD1/PD-L1-directed immunotherapy, alone or in combination with chemotherapy, dominates the initial treatment of metastatic non-small cell lung cancer. However, our ability to predict who will benefit from these approaches is limited. In this issue of Cell, Nabet et al. report a novel, blood-based methodology to more accurately predict durable disease control with immunotherapy.
Behavioral Foundations of Nested Stochastic Choice and Nested Logit

We provide the first behavioral characterization of nested logit, a foundational and widely applied model in discrete choice. We take a revealed preference approach to identify the underlying notion of similarity and use it to characterize a non-parametric version of nested logit we call Nested Stochastic Choice(NSC). We characterize NSC with a single axiom that weakens Independence of Irrelevant Alternatives(IIA) based on revealed similarity to allow for the similarity effect. Nested logit is then characterized by one additional axiom that imposes a weak form of menu-independence. We show that a widely applied generalization, cross-nested logit, lacks testable implications.
Useful Field of View Impairment in Partial Epilepsy

Patients with epilepsy are at elevated risk for automobile crashes. Most collisions in drivers with epilepsy are not seizure-related, but may instead result from cognitive effects of epilepsy and antiepileptic drugs (AEDs) upon driving performance. The Useful Field of View (UFOV) score has demonstrated good sensitivity and specificity for predicting automobile crashes. The goal in this pilot study was to assess impairments in the UFOV in subjects with partial epilepsy. Participants included 20 subjects with partial epilepsy. Neurologically normal control subjects of comparable age also participated. UFOV was assessed in all participants using the Visual Attention Analyzer, Model 3000 (Visual Resources, Inc.). UFOV Task scores were added to calculate a UFOV Total score for each subject. UFOV scores were higher on all UFOV tasks in subjects with partial epilepsy compared to neurologically normal individuals of similar age (p<0.05, Wilcoxon Rank Sum Test), suggesting a greater crash risk in individuals with partial epilepsy, even in the absence of an epileptic seizure. Causes of impaired UFOV scores include processing speed reduction, divided and selective attention impairments, and mild postoperative visual field deficits. The authors' ongoing studies in drivers with epilepsy are aimed at further differentiating potential effects of seizures, antiepileptic drugs, and surgical lesions upon cognitive abilities that are critical to safe automobile driving.
Rogue insiders, signature loopholes, and fraud rings

Purpose – The purpose of this paper is to report the findings and lessons learned from a case study that is based on Alibaba's business‐to‐business (B2B) fraud in China. The influence of such incidents and post‐hoc solutions are research worthy in today's booming digital business world.Design/methodology/approach – The paper uses a case study approach and practice‐driven method that rely on user behaviors, corporate policies, and financial data. The taxonomic framework of online fraud and corresponding countermeasures arise from digital forensic reports, policy reviews, data analysis, and a literature review.Findings – The key findings are indigenous to the Chinese B2B landscape, yet they help international stakeholders understand and address fraudulent issues. The paper finds beside the traditional customer‐based account signature, internal employees must be assigned their own signature systems to track malicious activities. Meanwhile, digital signature systems can be enhanced by reducing the record inte...
INDUCED BIOSYNTHESIS OF α-AMYLASE BY GROWING CULTURES OF BACILLUS STEAROTHERMOPHILUS

Welker, N. E. (Western Reserve University, Cleveland, Ohio), and L. Leon Campbell. Induced biosynthesis of alpha-amylase by growing cultures of Bacillus stearothermophilus. J. Bacteriol. 86:1196-1201. 1963.-The maximal differential rate (K) of alpha-amylase synthesis was usually two to three times that of the sucrose control culture, over an inducer concentration range of 5 x 10(-4) to 1 x 10(-3)m. With maltotetraose, higher concentrations decreased the K value, whereas higher concentrations of maltose were needed to obtain maximal K values. Glucose, in concentrations from 10(-5) to 10(-2)m, had no effect on the differential rate of enzyme synthesis. Cultures growing on maltotriose, maltotetraose, maltopentaose, and maltohexaose exhibited the same growth rate (k) and differential rate of alpha-amylase synthesis over a concentration range of 2.92 x 10(-4) to 1.46 x 10(-2)m. Growth of cultures in various concentrations of pure maltose revealed that with concentrations of maltose ranging from 2.92 x 10(-3) to 1.46 x 10(-2)m the K value for alpha-amylase production increased 18-fold. The amount of maltose utilized, during the growth period, at each concentration of maltose, was constant. Diauxic type growth was observed when maltose was used in addition to another carbon source (i.e., glucose, glycerol, fructose, or sucrose). Maltose was not utilized until the other carbon source had been metabolized. Phenyl-, methyl-, and ethyl-alpha-d-glucoside and methyl-beta-d-maltoside were good inducers of alpha-amylase and would not serve as a carbon source in a chemically defined medium supplemented with 0.1% casein hydrolysate. These compounds were therefore gratuitous inducers of alpha-amylase. Isomaltose, panose, butyl-alpha-d-glucoside, and methyl-alpha-d-maltotetraoside were not effective as inducers of alpha-amylase. Fructose had an inhibitory effect on constitutive (41%) and inducible (55%) alpha-amylase formation; glucose had no effect.
Motor System Organization

Control of voluntary movement involves the central nervous system from the spinal cord to the cerbral cortex. Keywords: motor cortex; muscles; spinal cord; cerebellum; basal ganglia
Protection of mouse photoreceptors by survival factors in retinal degenerations.

PURPOSE. TO examine the protective effect of a number of survival factors on degenerating photoreceptors in mutant mice with naturally occurring inherited retinal degenerations, including retinal degeneration (rd/rd), retinal degeneration slow (rds/rds), nervous (nr/nr), and Purkinje cell degeneration (pcd/pcd), in three different forms of mutant rhodopsin transgenic mice and in light damage in albino mice. METHODS. Various survival factors were injected intravitreally into one eye of mice at or soon after the beginning of photoreceptor degeneration, with the opposite eye serving as the control, and the eyes were examined histologically at later ages. The survival factors included brain-derived neurotrophic factor (BDNF), neurotrophin-3, neurotrophin-4, ciliary neurotrophic factor (CNTF), Axokine' M (a mutein of CNTF), leukemia inhibitory factor, basic fibroblast growth factor, and nerve growth factor and insulin-like growth factor II, either alone or in various combinations. RESULTS. Photoreceptor degeneration was slowed in rd/rd and nr/nr mutant mice and in Q344ter mutant rhodopsin mice by certain forms of CNTF; the degeneration in Q344ter mice was slowed by Axokine and by leukemia inhibitory factor; and the degeneration in a few nr/nr mice was slowed by BDNF. The other agents were ineffective in these mice, and none of the agents were effective in the other mutants and other mutant rhodopsin transgenic mice. However, light damage experiments that compared agent effectiveness in albino mice versus rats suggested a significant delivery problem with the very small mouse eye, thereby making the interpretation of negative findings equivocal in mutant mice. Basic fibroblast growth factor failed to protect the mouse retina from the damaging effects of constant light, whereas it showed a strong protective effect in the rat, indicating an important species difference. CONCLUSIONS. The slowing of degeneration in the rd/rd and Q344ter mutant mice demonstrated that intraocularly injected survival factors can protect photoreceptors from degenerating in animal models with the same or similar genetic defects as those in human inherited retinal degenerations. (Invest Opbthalmol Vis Sci. 1998;39:592-602)
Transanal endoscopic microsurgery in the treatment of select rectal cancers or tumors suspicious for cancer.

Background: This study describes a personal experience with the use of transanal endoscopic microsurgery to facilitate surgical access, and to determine the ability of this technique to reduce the need for major abdominal procedure and prevent the need for a temporary or permanent colostomy in select patients with known or suspected rectal cancer. Methods: The subjects of this study were 43 patients with rectal cancer or tumors who had a high likelihood of malignancy. The 24 men and 19 women comprised two groups: patients with known cancer (n = 16) and patients with tumors suspicious for cancer (n = 27), six of whom proved to have invasive malignancy. The tumors ranged in size from 1 to 7 cm (average, 3.5 cm). The tumor’s inferior level in the rectum ranged from −1 to 21 cm (average, 6.5 cm). Eleven patients known to have rectal cancer were treated with preoperative radiation or chemoradiation. By ordinary standards, 22 patients would have received an abdominal perineal resection; 14 patients would have qualified for abdominal sphincter–preserving operations; and 7 patients were indeterminate. Full-thickness local excisions were disk excisions (n = 23), hemicircumferential excisions (n = 19), and sleeve resection (n = 1). The ages of the patients ranged from 30 to 91 years (average, 66.7 years). Results: In this study, 90% avoided a major abdominal operation (39/43), and 90% avoided an abdominal perineal resection of the patients (20/22). The complications were as follows: mortality (n = 10), morbidity (n = 9), minor wound separation (n = 6), and major wound separation (n = 3). Two of these complications were rectovaginal fistulas: the one in a 91-year-old patient who presented with a fistula and the other in a 77-year-old patient who presented with a previously irradiated and incompletely excised cancer. A single instance of locally recurrent cancer required an abdominal perineal resection. There were no other recurrences. Overall, three patients required a stoma (7%). Conclusion: Transanal endoscopic microsurgery promises to offer a safe and effective option for the selective treatment of patients with rectal cancer after preoperative chemoirradiation, and for the management of tumors suspicious for rectal cancer. Transanal endoscopic microsurgery used selectively can reduce the need for major abdominal surgery and colostomy.
Modeling of regional climate change effects on ground-level ozone and childhood asthma.

Background The adverse respiratory effects of ground-level ozone are well established. Ozone is the air pollutant most consistently projected to increase under future climate change. Purpose To project future pediatric asthma emergency department visits associated with ground-level ozone changes, comparing 1990s to 2020s. Methods This study assessed future numbers of asthma emergency department visits for children aged 0–17 years using (1) baseline New York City metropolitan area emergency department rates; (2) a dose–response relationship between ozone levels and pediatric asthma emergency department visits; and (3) projected daily 8-hour maximum ozone concentrations for the 2020s as simulated by a global-to-regional climate change and atmospheric chemistry model. Sensitivity analyses included population projections and ozone precursor changes. This analysis occurred in 2010. Results In this model, climate change could cause an increase in regional summer ozone-related asthma emergency department visits for children aged 0–17 years of 7.3% across the New York City metropolitan region by the 2020s. This effect diminished with inclusion of ozone precursor changes. When population growth is included, the projections of morbidity related to ozone are even larger. Conclusions The results of this analysis demonstrate that the use of regional climate and atmospheric chemistry models make possible the projection of local climate change health effects for specific age groups and specific disease outcomes, such as emergency department visits for asthma. Efforts should be made to improve on this type of modeling to inform local and wider-scale climate change mitigation and adaptation policy.
Computer Science and Engineering Education

This paper provides a brief overview of significant developments in computer science and engineering education with discussions on curriculum development, continuing education, and certification. Forecasts of industry needs in the 1980's for computer professionals are included, together with the trends in curriculum developments that may auger.
Ferromagnetic Hall Effect in an Electron-Phonon Gas

The contribution of the electron-phonon interaction to the anomalous Hall effect in ferromagnetic metals is calculated, utilizing Holstein's transport theory of the electron-phonon gas. Specifically, the transverse dc conductivity ${\ensuremath{\sigma}}_{\mathrm{xy}}$ is calculated using Kubo's formalism and the temperature diagrammatic technique. Results based on the (ferromagnetically) polarized itinerant-electron model are consistent with the Luttinger's theory of the anomalous Hall effect for impurity scattering. This leads to the non-Boltzmann (so-called "anomalous-velocity") contribution as well as the skew-scattering contribution of the type first obtained by Smit. However, it is in disagreement with the result of Leribaux based on the same model. A principal feature of the treatment is the explicit representation in terms of charge-carrier motion between different Wannier cells as first suggested by Smit. However, in contrast to the latter author, who took the velocity operator of this intercell motion to be the ordinary Bloch velocity, it is found that there is an additional velocity component of intercell motion arising from the electron scattering mechanism (either electron-phonon interaction, as in this case, or electron-impurity interaction as in the previous treatments of Smit or Luttinger). This additional component gives rise, in turn, to the above-mentioned anomalous-velocity correction to ${\ensuremath{\sigma}}_{\mathrm{xy}}$, and hence, to the Hall coefficient.
Can Brokerage Have an Equilibrium Selection Role

Abstract This paper presents a model of housing markets with multiple search equilibria. There are two problems associated with multiplicity of equilibria. One is that the economy may end up at a Pareto inferior equilibrium, and the other is that it becomes more difficult to predict the effect of policy measures. The objective of this study is to examine whether the brokerage institution can resolve these problems. It is shown that brokerage can reduce the number of equilibria and can also improve welfare by moving the economy to a Pareto superior equilibrium. However, under certain conditions, brokerage reduces welfare and creates additional coordination problems by increasing the number of equilibria.
Applicability of Reduced-Gravity Shallow-Water Theory to Atmospheric Flow over Topography

AbstractApplicability of the reduced-gravity shallow-water (RGSW) theory to a shallow atmospheric layer capped by an inversion underneath a deep stratified atmosphere over a two-dimensional ridge has been investigated using linear analysis and nonlinear numerical simulations. Two key nondimensional parameters are identified: namely, and , where g′ is the reduced-gravity acceleration; H0 is the RGSW layer depth; and N and U are the buoyancy frequency and wind speed, respectively, in the layer above the inversion. If J and γ are around unity or larger, the response of the RGSW flow over the ridge can be significantly modified by pressure perturbations aloft. Any jumplike perturbations in the RGSW layer rapidly decay while propagating away from the ridge as the perturbation energy radiates into the upper layer. With J and γ much less than unity, RGSW theory is more adequate for describing RGSW flows.In addition, inversion splitting occurs downstream of a jump when , where Ni is the buoyancy frequency in the ...
Micro fixture enabled in-situ imaging and manipulation of cell membrane protein

This paper presents a new and reliable approach for in-situ imaging and manipulation of membrane protein molecules. The major problematic issue in medicine is the lack of fundamental understanding of the molecular mechanisms that cause major life-threatening and incurable diseases. The development of atomic force microscopy (AFM) opens an entirely new way to address these medical questions. A biocompatible porous polymer micro-mesh is designed for immobilizing living cells and protein molecules during AFM scanning. We demonstrate its usefulness by imaging cancerous B-cells as well as cell-junction molecules associated with living epithelial cells at high resolution. This technology can not only be used for imaging, but also for nanomanipulation. Current results suggest that this AFM nanomanipulation system and the novel cell fixture apparatus can be used to study the dynamic changes and function of cellular structures with unparalleled resolution both under physiological and pathophysiological conditions.
Infrared Multiphoton Dissociation Spectroscopy of Cationized Threonine: Effects of Alkali-Metal Cation Size on Gas-Phase Conformation

The gas-phase structures of alkali-metal cation complexes of serine (Ser) are examined using infrared multiple photon dissociation (IRMPD) spectroscopy utilizing light generated by a free electron laser, in conjunction with ab initio calculations. Spectra of Li+(Ser) and Na+(Ser) are similar and relatively simple, whereas Cs+(Ser) includes distinctive new IR bands, and K+(Ser) and Rb+(Ser) exhibit intermediate behavior. Measured IRMPD spectra are compared to spectra calculated at a B3LYP/6-311+G(d,p) level to identify the structures present in the experimental studies. On the basis of these experiments and calculations, the only conformations accessed for the complexes to the smaller alkali-metal cations, Li+ and Na+, are charge-solvated structures involving tridentate coordination to the amine and carbonyl groups of the amino acid backbone and to the hydroxyl group of the side chain, M1[N,CO,OH]. For the cesiated complex, a band corresponding to a zwitterionic structure, ZW[CO2-], is clearly visible. K+(Ser) and Rb+(Ser) exhibit evidence of the charge-solvated analogue of the zwitterions, M3[COOH], in which the metal cation binds to the carboxylic acid group. Calculations indicate that the relative stability of the M3[COOH] structure is very strongly dependent on the size of the metal cation, consistent with the range of conformations observed experimentally.
Development, Distribution and Movement of Cyclones and Anticyclones in the Southern Hemisphere During the IGY

Abstract Charts showing the seasonal frequency distribution of anticyclones, cyclones and cyclogeneses (centers of cyclogenesis) in the Southern Hemisphere south of 15S during the International Geophysical Year are presented. Meridional profiles of the zonal frequencies of the systems are compared with corresponding profiles of sea level pressure and wind, 1000–500 mb thermal wind and 500-mb geostrophic wind. Examples of typical cyclone and anticyclone tracks and of the movement of systems during periods with anomalous circulation are given.
Composition of mitochondrial preparations in relation to intracellular localization of azoprotein in the mouse.

Conclusions and SummaryThese studies substantiate previous reports that a relatively large proportion of injected labeled protein is found in the mitochondrial fraction of homogenized liver(8). Failure to demonstrate in this fraction the azoprotein which was added to the whole liver homogenate indicates that an in vivo process is involved and that simple adsorption of the azoprotein by mitochondria does not occur. Results of microscopic study of wafers, made by centrifuging mitochondrial fractions, indicate that the intracytoplasmic granules of azoprotein seen in sections from injected animals(1-3,5) are found predominantly in such mitochondrial fractions. However, the facts that injected India ink particles occur in a similar proportion in such fractions, that the azoprotein granules do not take various mitochondrial stains, and that other impurities can be demonstrated in such preparations, indicate that such mitochondrial fractions do not consist only of mitochondria. This conclusion has also been expr...
Radiation tolerance of ultra-thin Formvar films

Mechanical behavior of free-standing polymer films with submicron thicknesses exposed to a radiation environment is poorly understood. Here, we study 110-nm-thin free-standing polyvinyl formal (Formvar) films irradiated at room temperature with 1–5 keV electrons or 3 MeV alpha particles. We measure mechanical properties and the elemental composition by spherical indentation and high-energy ion scattering, respectively. Results show that, with increasing radiation dose, the effective failure strain and film thickness decrease monotonically, while the dose dependence of the Young’s modulus is non-monotonic. The failure strain and modulus scale with the average energy deposited in the film, while the film thickness exhibits a more complex behavior.
Some Uses of Alternating Current Supply

The alternating current supply is a convenient source of current in frequency measurements and comparisons, unless high degree of constancy is desired. An ac arc also is a fairly satisfactory intermittent source of light. A number of experiments are described, making use of these facts:(1)The motion of a tuning fork and explanation of beats.(2)Waves on liquids can be shown, including the case of beats.(3)Slight phase changes may be shown when a heavy motor is connected to the line.(4)An audio-oscillator may be calibrated.(5)Reaction of closely and loosely coupled circuits may be mechanically demonstrated; and an explanation found for the difficulties sometimes encountered in Melde’s Experiment. Also, there are explained two useful theorems in connection with Lissajou figures.
A procedure for obtaining radioactive naringin from grapefruit leaves fed L-phenylalanine-14C

Abstract Radioactive naringin, naringenin-7β-neohesperidoside, the principal bitter constituent of grapefruit (Citrus paradisi) and its radioactive tasteless isomer, naringenin-7β-rutinoside, were isolated from young grapefruit leaves fed L -phenylalanine-14C. Radiolabeled L -phenylalanine is taken up by young grapefruit leaves through the petioles and the leaves are then allowed to metabolize the phenylalanine during periods of 12 hr of light and 12 hr of dark. Extraction of the leaves with hot methyl alcohol, followed by concentration and column chromatography afforded both the bitter naringin and its tasteless isomer. Final separation and purification of both compounds were accomplished by thin-layer chromatography. These results demonstrate that L -phenylalanine can serve as a precursor to naringin in grapefruit leaves.
Abortion and the Ethics of Genetic Sexual Orientation Research

Research is being conducted to determine whether there is a genetic basis for homoerotic sexual orientation in adults. Reports indicate that such a basis may exist. Some homosexual men and women have welcomed the possibility of biological confirmation of their sexual orientation and subsequent behavior. If human sexual orientation were proven to be genetically determined many homosexuals would not feel compelled to justify their sexuality. One would simply be born either homosexual or heterosexual. Others however worry that the ability to identify homosexuality through genetic markers may be used prejudicially against homosexuals. German sexologist Gunter Schmidt has argued that since society has yet to fully accept homosexuals and homosexuality research into the possible causes of homosexuality is potentially dangerous to gay men and women. In the same vein gay studies scholar David Halperin argues that the search for a scientific etiology of sexual orientation is a homophobic venture which should be clearly seen as such. Considerable concern therefore exists that sexual orientation research may lead to genocide against homosexuals through the practice of selective abortion on the basis of a fetuss genetically identified sexual orientation. The author however is skeptical that a simple genetic test is on the horizon which is capable of determining an individuals sexual orientation and were such a test available that it would necessarily be used only to the detriment of homosexuals. He does acknowledge that such a test could be used prejudicially with regard to access to employment insurance and other social goods but it nonetheless remains unjustified to completely forbid genetic sexual orientation research. A sexual orientation test and abortion and the ethics of sexual orientation research are discussed.
Ocean color remote sensing systems - Radiometric requirements

A methodology for specifying the radiometric requirements for ocean color remote sensing systems is described. Consideration is given to the noise equivalent radiance, the saturation radiance, the polarization sensitivity, and the calibration and stability. The degree of polarization across a scan line for the CZCS and MODIS orbits is presented.
Unequal Cell Division as a Driving Force During Differentiation

Unequal cell division, leading to daughter cells of different sizes, is a common event during development. We have formulated a model that shows how different cell sizes can lead to significant differences in the expression of an activator gene. The model is based on well-known aspects of the regulation of gene expression, specifically the existence of multiple regulatory sites, positive autoregulation, and the short half-life of regulatory proteins. Thus the daughter cells may follow distinct differentiation pathways even if there were no localized determinants in the mother cell.
Urorectal septal defects in a female and her offspring

We report on a patient with an ectopic urethra opening into a septate vagina which was distended with urine. The anus and rectum were normal but separated from the urogenital sinus by a thin septum. After surgical repair the patient did well with the exception of recurrent urinary tract infections. At 16 years, she delivered a healthy boy by Cesarean section but miscarried a subsequent pregnancy 3 years later. The 12-13 week female fetus lacked a urethra and had an atretic vagina and cloacal anomalies consistent with a urorectal septum developmental defect. This report provides evidence that cloacal anomalies resulting from the improper development of the urorectal septum may have a genetic cause. Furthermore, we support the proposition previously set forth by Allen and Husmann [J Urol 145:1034-1039, 1991] that such anomalies be referred to as urorectal septal defects rather than cloacal anomaly variants. This terminology accurately represents the developmental defect and clearly distinguishes them from cloacal exstrophies, which are due to the abnormal development of the cloacal membrane and the subumbilical ventral abdominal wall.
Linear-Response Studies of the Electron-Phonon Interaction in Metals

Applications of the first-principles linear-response method for calculating electron-phonon coupling parameters are presented. Calculations show that the electron-phonon coupling in the low-temperature 9R phase of Li is significantly weaker than in the room-temperature b.c.c. phase, which helps explain the observed absence of a superconducting transition down to the mK regime. Results for the electron-phonon interaction in compressed S indicate that the surprisingly high superconducting T c of 17 K observed at 160 GPa arises from a combination of a moderately large electron-phonon mass enhancement parameter and a very high phonon energy scale for the compressed lattice.
The role of protonation, hydration, elimination, and ring opening in the electroreduction of hexazinone

The herbicide hexazinone (3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4 (lH,3H)-dione) is a 1,3,5-triazine derivative which exists in a single cyclic tautomeric form. In the presence of water its azomethine bond is covalently hydrated (Kd=0.79, in acetonitrile as a predominant co-solvent) and protonated (pKa=1.2). Following dehydration, the protonated form of the azomethine bond undergoes a two-electron reduction in wave I1. The decrease in current at pH>2.5 results from the decrease in the rate of protonation (kr=6.3×106 mol−1 s−l). The current at pH 2 to 4 is smaller than theoretical due to a competitive hydration. The two-electron reduction product formed in waves undergoes elimination of dimethylamine. The resulting azomethine bond in the product of elimination is reduced in wave I2. The oxidized form of hexazinone undergoes an acid-catalyzed ring opening at pH<1.3. The acid catalysis is attributed to a protonation of the hydrated form of the heterocycle. The formyl group of the open-chain form is reduced in a more negative wave I1a. Ac polarography indicated adsorption of the oxidized form of hexazinone, dc polarography and voltammetry show also an adsorption of its reduced form.
Verification and validation of an atmospheric boundary layer passive remote sensing technique using midwave infrared downwelling radiance

Passive radiometric remote sensing of the lower atmospheric is an attractive alternative to conventional techniques such as balloonsondes and active radiometric sensing with lidars. Measurements can be made with high sampling frequency, with complete safety and covertness, and with no loss in performance during day or night operation. A recently developed inversion algorithm generates vertical profiles of temperature and water vapor partial pressure from midwave infrared downwelling radiance to a ground based spectroradiometer. The technique is fast allowing real-time profile computation. Profiles up to 1 km altitude can be obtained for temperature and up to 0.5 to 1 km altitude for water vapor depending on the level of relative humidity. As with any new technique a verification and validation process must be performed to achieve acceptance. The verification is based on the fact that sound physical principles are employed with accepted databases (HITRAN spectroscopic database). The validation is based on comparisons with balloonsonde, MET tower, and Raman lidar measurements, and comparisons with MODTRAN 4 calculations of downwelling radiance using known profiles. An introduction to the inversion algorithm emphasizing verification is presented. This is followed by a discussion of the results from the comparison study.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Performance Characteristics of the 30 MeV Three-Stage Tandem Facility at BNL

The 30 MeV 3-stage Van de Graaff facility at Brookhaven National Laboratory achieved the desired operating specifications on July 28, 1970 and has been in operation on various research programs since. The facility consists of two MP Tandem Van de Graaff accelerators arranged in line with a negative ion source installed in the terminal of the first accelerator. The two accelerators can either be used as separate Tandem accelerators or together in a 3-stage configuration. Proton energies as high as 30.5 MeV with currents as high as 4 microamperes have been obtained.
Cellular immune response in virus infections

Two levels of specificity exist in the killing of virus infected target cells by immune effector T cells. One relates to the classic specificity for the virus, and the second involves the necessity for sharing expression of genes mapping in K and D but not I regions. Among the theories that could explain this is that of dual recognition with separate T-cell receptors detecting H-2 and viral antigen. Support for this possibility was provided by experimental influenza virus infection where evidence of specific recognition of viral products was obtained.
Comparative Political Philosophy and Liberal Education: "Looking for Friends in History"

importance (since part of liberal education is coming to terms with a particular historical past or tradition); the extent to which they are open to conflicting interpretations (since critical interpretation and argument about the meaning of words and things is the practice that defines the liberal classroom); and the extent to which they can be read with an eye to questions and problems of the present (since liberal education is justified largely by its capacity to encourage deliberation and informed action in the
Synthesis of linear and starlike polymers from poly(propylene glycol) methacrylate using controlled radical polymerization

The copper-catalyzed atom transfer radical polymerization (ATRP) of poly(propylene glycol) methacrylate (PPGM) in solution to produce linear and starlike polymers is reported, using methylethyl ketone as the solvent and a temperature of 80 °C. The ATRP system used was efficient for polymerization of the functionalized monomer without protecting hydroxyl end groups of monomer. The polymerizations were consistent with “living” or controlled processes, as revealed by the linear evolution of molecular weight with conversion. Increasing the [M]0:[I]0 ratio resulted in increasing molecular weights, whereas the polydispersity indices remained low (Mw/Mn < 1.4) even at high conversion. Decreasing the [CuBr]0:[I]0 ratio resulted in lower conversions, slightly larger polydispersities, and decreased molecular weights, likely resulting from a lower initiation efficiency. Polymers were characterized by 1H and 13C NMR; molecular weights of polymers with low degrees of polymerization were estimated by end-group analysis from 13C NMR spectra obtained using distortionless enhancement by polarization transfer and the gated decoupling techniques. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 334–343, 2002
Application of the method of weighted residuals to mixed boundary value problems: Dual-series relations

Abstract Mixed boundary value problems arise in a number of chemical engineering models for heat conduction, simultaneous diffusion and reaction, and fluid flow whenever there is a change in the type of boundary condition along the same boundary. In this paper a general computer algorithm based on the method of weighted residuals (MWR) is developed for determining approximate solutions of all problems of the above type which lead to dual series equations. The solution procedure reduces the determination of the series coefficients to the solution of a large system of algebraic equations. This technique offers advantages over finite difference or artificial interface methods in the accuracy which can be obtained, the type of problem which may be treated, and the simplicity of calculations to be performed. Solutions obtained by the application of MWR are compared and analysed for three example problems which are of interest in diffusion, reaction and conduction.
Impact of β-Sheet Conformations on the Mechanical Response of Protein in Biocomposites

Proteins in biological nanocomposites play an important role in their mechanical response. Proteins in nacre, the inner layer of seashells, have been shown to have exceptional mechanical properties. One of the important nacre proteins, Lustrin-A, has abundance of polypeptides in zig-zag conformation called β-sheets. β-sheets of protein when present close to each other in multiple numbers could take the shape of a planar β-sheath like structure or a β-barrel to form a domain. In natural proteins both these types of structures are commonly found. However, the conformation of β-sheets in Lustrin-A is not known at this time. Effort has been made through this work to study the mechanical response of these β-planar sheath and β-barrel structures when subjected to external loads. Comparative study of the stress-deformation characteristics of these two types of structures has been made. Both these structures with almost similar number of amino acids have been extracted from one single spinach protein: Ferredoxin ...
A block QR factorization algorithm using restricted pivoting

This paper presents a new algorithm for computing the QR factorization of a rank-deficient matrix on high-performance machines. The algorithm is based on the Householder QR factorization algorithm with column pivoting. The traditional pivoting strategy is not well suited for machines with a memory hierarchy since it precludes the use of matrix-matrix operations. However, matrix-matrix operations perform better on those machines than matrix-vector or vector-vector operations since they involve significantly less data movement per floating point operation. We suggest a restricted pivoting strategy which allows us to formulate a block QR factorization algorithm where the bulk of the work is in matrix-matrix operations. Incremental condition estimation is used to ensure the reliability of the restricted pivoting scheme. Implementation results on the Cray 2, Cray X-MP and Cray Y-MP show that the new algorithm performs significantly better than the traditional scheme and can more than halve the cost of computing the QR factorization.
Imaging of Surface-Tension-Driven Convection Using Liquid Crystal Thermography

Surface-tension forces can drive fluid motion within thin liquid layers with a free surface. Spatial variations in the temperature of the free surface create surface tractions that drive cellular motions. The cells are most commonly hexagonal in shape and they scale on the thickness of the fluid layer. This investigation documents the formation of cells in the liquid film in the presence of a uniform-heat-flux lower boundary condition. Liquid crystal thermography was used to image the cells and measure the temperature distribution on the lower surface of the liquid layer. A 1.1 mm deep pool of silicone oil was supported on a 50 μm thick electrically heated metal,foil. The oil was retained inside an independently heated acrylic ring mounted on the top surface of the foil and a dry-ice cooling plate served as the low-temperature sink above the free surface of the oil. Color images of hexagonal convection cells were captured using liquid crystal thermography and a digital image acquisition and processing system. The temperature distribution inside a typical cell was measured using thermographic image analysis. Experimental issues, such as the use of an independently heated retaining ring to control the height of the liquid film and the utility of a flux-based Marangoni number are discussed.
A prolonged cartilaginous phase in newt forelimb skeletal regeneration

The morphologic events leading to the regrowth of the amphibian limb have long been known, yet it is poorly appreciated that even when the limb appears outwardly restored, its skeletal parts may be formed entirely of cartilage. To determine when forelimb skeletal ossification begins and is completed in the spotted newt Notophthalmus viridescens, limbs from animals that had sustained midhumeral amputations were examined at intervals of up to 270 days. At this time, most regenerated skeletal parts were undergoing ossification, but those of the wrist remained entirely cartilaginous. Calcium content of regenerated bones was deficient, and X-ray diffraction analysis disclosed the presence of apatite crystals with minimally discernible orientation.
Regulation of the IgE Antibody Response

The IgE synthesis is regulated by T cell derived IgE-binding factors in an isotype-specific manner. The IgE-potentiating and IgE-suppressive factors may share common structural genes; therefore, a common polypeptide chain and their biologic activities are determined by posttranslational glycosylation processes. Under the physiological conditions, the carbohydrate moieties in the IgE-binding factors formed by a subset of T cells are determined by the ratio between two T cell factors, i.e., glycosylation-enhancing factors and glycosylation-inhibiting factors (GIF), in their environment. GIF is an immunosuppressive lymphokine. Repeated injections of this lymphokine into antigen-primed mice facilitated the generation of antigen-specific suppressor T cells and suppressed both IgE and IgG antibody responses. This effect of GIF was reproduced in vitro. Activation of antigen-specific T cells by antigen-pulsed macrophages, followed by propagation of the antigen-activated T cells by interleukin 2 in the presence of GIF resulted in the generation of suppressor T cells which produced antigen-specific GIF upon antigenic stimulation. Some of the T cell hybridomas constructed from the antigen-specific suppressor T cells formed antigen-specific GIF upon antigenic stimulation. The antigen-specific GIF formed by the T cell hybridoma share several common properties with antigen-specific suppressive factor and suppressed the antibody response of syngeneic mice in a carrier-specific manner. The results obtained with mouse lymphocytes suggest a maneuver to suppress the IgE antibody formation to an allergen in atopic patients.
Knowledge-based optical coatings design and manufacturing

The theory of thin film optics is well developed for the spectral analysis of a given optical coating. The inverse synthesis - designing an optical coating for a certain spectral performance - is more complicated. Usually a multitude of theoretical designs is feasible because most design problems are over-determined with the number of layers possible with three variables each (n, k, t). The expertise of a good thin film designer comes in at this point with a mostly intuitive selection of certain designs based on previous experience and current manufacturing capabilities. Manufacturing a designed coating poses yet another subset of multiple solutions, as thin if in deposition technology has evolved over the years with a vast variety of different processes. The abundance of published literature may often be more confusing than helpful to the practicing thin film engineer, even if he has time and opportunity to read it. The choice of the right process is also severely limited by the given manufacturing hardware and cost considerations which may not easily allow for the adaption of a new manufacturing approach, even if it promises to be better technically (it ought to be also cheaper). On the user end of the thin film coating business, the typical optical designer or engineer who needs an optical coating may have limited or no knowledge at all about the theoretical and manufacturing criteria for the optimum selection of what he needs. This can be sensed frequently by overly tight tolerances and requirements for optical performance which sometimes stretch the limits of mother nature. We introduce here a know1edge-based system (KBS) intended to assist expert designers and manufacturers in their task of maximizing results and minimizing errors, trial runs, and unproductive time. It will help the experts to manipulate parameters which are largely determined through heuristic reasoning by employing artificial intelligence techniques. In a later state, the KBS will include a module allowing the layman user of coatings to make the right choice.