cssi/SciSciGPT-SciSciNet huggingface dataset:
High frame rate imaging with diverging beam transmission and fourier reconstruction

A high frame rate imaging method where a limited diffraction beam is used in transmission and received echo signals are processed with both temporal and spatial fast Fourier transforms to reconstruct images has been developed previously. However, this method has a limitation that objects to be imaged are illuminated only within the projection of transducer aperture. To reconstruct images of a large field of view at a large distance, multiple transmissions are required to illuminate the entire objects and thus image frame rate may be reduced. To overcome such a limitation, in this paper, diverging beams that can illuminate a larger area in one transmission are used while the same temporal and spatial fast Fourier transforms as in the high frame rate imaging method are used to reconstruct images. Results show that images reconstructed with diverging beams of a diverging angle up to 15 degrees in transmission have a reasonable image quality as compared to that of images reconstructed with a limited diffraction beam in transmission (in theory, limited diffraction beams have 0 degree diverging angle).
Frequency modulation spectroscopy with a tunable CO 2 sideband laser: ozone detection

The unblended ozone line at 1044.533 cm-1 was acquired by using the frequency modulation technique. A tunable CO2 sideband laser with a GaAs waveguide modulator with a tuning bandwidth of 20 GHz in the mid-infrared region was used for this method. With this technique, a second sideband at 1-MHz frequency with a peak-to-peak amplitude of 1 V was imposed on the first tunable sideband. The signal was passed through a 1-m cell and collected with an EG&G detector. The signal-to-noise ratio obtained was approximately 100:1.
Effect of boundary conditions and spacers on single-lap joints loaded in tension or compression

The mechanics of a single-lap joint with different boundary conditions subjected to tensile or compressive loading is investigated. The analysis includes spacers used to reduce alignment errors. The closed-form solutions confirm that for tensile loading, the different grip configurations mainly affect the response of the specimens if the grip position is close to the overlap edge or the loads are small. The influence of the spacers is more significant for specimens subjected to compressive loads. Generally, adding alignment spacers tends to reduce the deflection along the specimen, and decrease the bending moment at the overlap edge.
Interaction of growth hormone and ACTH in the regulation of adrenocortical secretion in rats.

Effects of growth hormone, alone or in combination with ACTH, on adrenal function in hypophysectomized rats were examined. Hypophysectomy reduced corticosterone secretion and increased adrenal 5α-reductase activity. Growth hormone, administered alone to hypophysectomized rats, lowered reductase activity without affecting corticosterone secretion. ACTH alone increased corticosterone output but only partially reversed the increment in reductase activity. As a result, ACTH-treated rats secreted large amounts of 5α-dihydrocorticosterone (DHB) and 3β-5α-tetrahydrocorticosterone (R), the principal adrenal metabolites of corticosterone. Growth hormone, when given with ACTH, potentiated the effects of ACTH by stimulating corticosterone secretion and lowering 5α-reductase activity further. The additional increment in corticosterone resulted in part from a decline in the secretion of DHB and R. These results indicate that growth hormone plays a role in the maintenance of adrenocortical secretion which is at least p...
Elemental abundance analyses with DAO spectrograms — XXII. The B9-A3 stars λ Ursae Majoris, 59 Herculis, 14 Cygni and 29 Cygni

Elemental abundances of the moderately rotating B9–A3 stars λ UMa, 59 Her, 14 Cyg and 29 Cyg have been derived in a consistent manner with previous studies of this series from spectrograms obtained with Reticon and CCD detectors. The derived elemental abundances show that λ UMa is a mild Am star, while 59 Her is slightly metal-rich. Although 14 Cyg has values closer to solar than these stars, its subsolar Ca and Sc abundances indicate that it might be the hottest known hot-Am star. 29 Cyg is a metal-poor λ Boo star.
Simplified Anisotropic Plasticity Model for Analyzing the Postyield Behavior of Cold-Formed Sheet-Metal Shear Panel Structures

AbstractA simplified anisotropic constitutive model for orthotropic metal sheets is developed herein to analyze the off-axial stress-strain response of cold-formed metal sheets, where the material plastic anisotropy is induced by work hardening during the forming process. Hill’s 1948 anisotropic yield criterion is used to determine the material initial yielding, and the strain hardening is modeled using a mixed kinematic-isotropic hardening law along with constantly changing material principal directions as a result of the off-axial plastic loading. The isotropic hardening parameters were expressed using Fourier series and are functions of the loading directions. The expression of hardening parameters using Fourier series allows the model to be adaptively calibrated to the current state of stress using as few as three sets of off-axial stress-strain data. The proposed model is able to predict the direction-dependent strain hardening behavior of orthotropic metal sheets, as well as account for the progress...
Estimating forest biomass and volume using airborne laser data

An airborne pulsed laser system was used to obtain canopy height data over a southern pine forest in Georgia in order to predict ground-measured forest biomass and timber volume. Although biomass and volume estimates obtained from the laser data were variable when compared with the corresponding ground measurements site by site, the present models are found to predict mean total tree volume within 2.6 percent of the ground value, and mean biomass within 2.0 percent. The results indicate that species stratification did not consistently improve regression relationships for four southern pine species.
High-Pressure Photoluminescence Study of Fullerene C70†

The effect of pressure on the luminescence spectrum of the fullerene C70 was measured to 100 kbar. There was a substantially linear shift on the emission envelope to lower energy by about 450 cm-1 in 100 kbar. At the same time the envelope narrowed measurably. The shift is much more like that observed for olefinic compounds than for aromatics. The shift in the latter case is several times larger and distinctly nonlinear.
Identifying the trigger of c-IAPs: structural and functional characterization of CARD-mediated modulation of ubiquitin ligase activity.

In this issue of Molecular Cell, Lopez et al. (2011) examine the caspase-recruitment domain (CARD) of c-IAP1 to reveal an intriguing mechanism in which conformational changes of the CARD determine c-IAP1's ubiquitin ligase activity, with implications for regulation of cell proliferation and survival by the IAPs.
Acentric 2-D ensembles of D-br-A electron-transfer chromophores via vectorial orientation within amphiphilic n-helix bundle peptides for photovoltaic device applications.

We show that simply designed amphiphilic 4-helix bundle peptides can be utilized to vectorially orient a linearly extended donor–bridge–acceptor (D-br-A) electron transfer (ET) chromophore within its core. The bundle’s interior is shown to provide a unique solvation environment for the D-br-A assembly not accessible in conventional solvents and thereby control the magnitudes of both light-induced ET and thermal charge recombination rate constants. The amphiphilicity of the bundle’s exterior was employed to vectorially orient the peptide–chromophore complex at a liquid–gas interface, and its ends were tailored for subsequent covalent attachment to an inorganic surface, via a “directed assembly” approach. Structural data, combined with evaluation of the excited state dynamics exhibited by these peptide–chromophore complexes, demonstrate that densely packed, acentrically ordered 2-D monolayer ensembles of such complexes at high in-plane chromophore densities approaching 1/200 A2 offer unique potential as act...
Intraoperative urinary output and postoperative blood urea nitrogen and creatinine levels in patients undergoing aortic reconstructive surgery

Urinary output has been used as a measure of adequate renal perfusion during anesthesia and surgery. In this study, 40 consecutive patients undergoing elective aortic reconstruction were studied to determine whether intraoperative urinary output was predictive of postoperative renal function as measured by blood urea nitrogen (BUN) and creatinine concentrations on postoperative days 1, 3 and 6, or 7. Pulmonary capillary wedge pressures or central venous pressures were kept at or above preoperative values. All patients received 22.5 g of mannitol IV prior to aortic crossclamping. No significant correlation was noted between either mean intraoperative urine output or lowest hourly urine output and postoperative BUN and creatinine concentrations. Complete interruption of renal blood flow in nine of the 40 patients had no significant effect on the correlations. Consequently, intraoperative urine output does not appear predictive of postoperative renal insufficiency in patients undergoing elective aortic reconstruction.
COST-EFFECTIVENESS OF MEDICAL MANAGEMENT STRATEGIES FOR NEPHROLITHIASIS

ABSTRACTPurpose: We evaluated the cost-effectiveness and stone recurrence rates of common management strategies in stone formers.Materials and Methods: A decision tree model was created to compare the costs of 6 medical treatment strategies, namely dietary measures alone (conservative), empiric drug treatment (empiric), or directed drug therapy based on simple or comprehensive metabolic evaluation. The model assumed cost accrual for evaluation, medications, emergency treatment and surgery for stone recurrence. We determined recurrence rates, medical evaluation sensitivity and the risk reduction of medical treatments from the literature and the costs of surgery, emergency room and medical evaluation at our county hospital. Drug costs were obtained from 2 national pharmacy chains.Results: In first time stone formers conservative treatment was the least costly strategy and it yielded a stone formation rate of 0.07 stones per patient yearly. In recurrent stone formers conservative treatment was less costly th...
Social Welfare Policy as a Specialization in the Graduate Social Work Curriculum

I see—or fear that I see—a rather marked contrast between our teaching of public welfare and our teaching of casework. . . . In casework teaching, at any rate, we give conscious attention to the process by which decisions about an individual are reached. We give a theoretical framework that helps students determine what knowledge is rele vant and needed for the particular deci sion; we teach them how to get this knowl edge from the literature on casework, from clients, and from collaterals. . . . Do we teach public welfare this way? Would it not be an appropriate way to teach it? I should consider it most appropriate, for I see no difference in the process of arriving at intelligent and responsible decisions with reference to an individual and with refer ence to a question of social policy.1
Determinants of Response Recovery in Extinction Following Response Elimination

Abstract Elimination of autoshaped responding by random or negatively-contingent response-reductive procedures may leave a previously acquired association intact; however, two previous studies suggest that response elimination by backward conditioning may have more permanent effects. In Experiments 1 and 3, the autoshaped responding of pigeons was eliminated by a backward or negative contingency. Although speed of recovery during a subsequent extinction phase was greater following the backward contingency in Experiment 3, level of recovery did not differ as a function of response elimination procedure in either experiment. A possible basis for the discrepancy between the present and previous findings is the contingency arranged between the conditioned and unconditioned stimuli (CS and US, respectively) during forward conditioning. In Experiments 1 and 2, probability of US presentation following the CS ( p (US|CS) = 0.4 or 1.0) was varied within (Experiment 1) or between (Experiment 2) groups of birds. In both cases, level of recovery was higher following training under ( p (US|CS) = 0.4). The results are consistent with a memory retrieval theory in which unreinforced trials function as a retrieval cue for not responding.
World-Wide Education for the Humanitarian Technology Challenge [Guest Message]

The IEEE/United Nations/Vodaphone Foundation's Humanitarian Technology Challenge (HTC) and IEEE Humanitarian Technology Network (HTN) are international efforts to bring the vast engineering expertise of the IEEE membership to bear on technological challenges arising out of humanitarian efforts in the developing world. Recently, these programs have been augmented with an educational component entitled “World-Wide Education for the Humanitarian Technology Challenge” (we-HTC). This initiative focuses on the introduction of educational programs that promote and enhance the development of technological solutions for the developing world. While the main focus is at the university level (e.g., via capstone design courses), educational resource materials will be available for practicing engineers involved in the IEEE HTC/HTN efforts.
Recent progress in chemical detection with single-walled carbon nanotube networks

Single-walled carbon nanotubes (SWNTs) have had significant impact on the development of gas sensors in the last decade. However, useful applications of SWNTs are limited by the lack of manufacturable routes to device formation. This Highlight article chronicles recent progress in this area and demonstrates the great promise of a new room temperature deposition method for SWNT networks in gas sensing applications. This liquid deposition technique allows the deposition of pre-treated, highly aligned SWNT networks on a wide variety of substrates. A significant advantage of SWNT-network sensors is that fluctuations in the electrical response of individual SWNTs become less important as the size of the network increases. Therefore, device properties can be controlled by the overall density of the network rather than the physical properties of any individual SWNT. At densities where semiconducting pathways dominate, highly sensitive thin-film chemoresistive sensors can be fabricated. Such devices also have higher signal-to-noise ratios and are easier to fabricate than devices based on a single SWNT.
Collaborative integration in e-business through private trading exchanges (PTXs)

Collaborative integration is e-business process integration with supply chain partners such that there is a tightly-coupled collaborative relationship among all partners, deep visibility across all tiers of the supply chain, and near-real-time information exchange and knowledge sharing around supply chain processes. Enterprises seek to implement collaborative integration in order to realize the value-added benefits and cost savings of superior supply chain management, while enabling intelligent action and faster response to environmental variability. Increasingly, supply chain leaders are building private trading exchanges (PTXs) in order to more effectively enable and manage such collaborative integration. This paper examines the value proposition and the spectrum of solutions and services around collaborative integration through PTXs. The paper first identifies the challenges of collaborative integration in near-real-time supply chains. It then describes the building blocks of a PTX solution. It develops a comparative value proposition for collaborative integration. It then provides an illustrative case example from Viacore Inc. The paper ends with an examination of the future of collaborative integration in lean e-business environments.
Comment on James R. Cohen's “abandoned housing: Exploring lessons from Baltimore”

Abstract Baltimore and the State of Maryland spend tens of millions of dollars to demolish the city's physical fabric—its row houses, which once constituted vibrant neighborhoods and which developers now spend millions to recreate in the suburbs. But the demolitions are often counterproductive and sometimes just bad policy. As Cohen relates, the demolition of a dangerous or crime‐ridden row house is often followed by a vacant lot used for dumping trash or dealing drugs. The problems flowed not from the architecture, but from the surrounding social conditions. An alternate approach leaves behind the dangerous physical determinism that is at the heart of the demolition strategy and focuses instead on investing in peoples’ lives and welfare.
A novel algorithm for computing the 1-D discrete Hartley transform

An efficient split algorithm for calculating the one-dimensional discrete Hartley transforms, by using a special partitioning in the frequency domain, is introduced. The partition determines a fast paired transform that splits the 2/sup r/-point unitary Hartley transform into a set of 2/sup r-n/-point odd-frequency Hartley transforms, n=1:r. A proposed method of calculation of the 2/sup r/-point Hartley transform requires 2/sup r-1/(r-3)+2 multiplications and 2/sup r-1/(r+9)-r/sup 2/-3r-6 additions.
Use of Force and Attitude Sensors for Locomotion of a Legged Vehicle over Irregular Terrain

A number of legged vehicles are being developed for their mobility characteristics over irregular terrain. One such vehicle is The Ohio State University Hexapod vehicle (OSU Hexapod). Recently, the vehicle has been modified so that it can successfully walk over uneven terrain. Each of the feet has been equipped with two semiconductor strain gauges to measure lateral forces and a piezoelectric load cell to measure vertical forces. A vertical gyroscope and pendulums for orientation sensing have also been added.The control of locomotion over rough terrain can be decomposed into two complementary control processes, attitude control and active compliance. Attitude control is used to maintain the body tilt in a desired orientation, and active compliance is used to provide a suspension system by distributing force loading among the legs. It has been found that optimal force setpoints for the active-compliance algorithm can be calculated in closed form.This paper discusses the sensing hardware and the control sys...
Deracialization in the Deep South: Mayoral Politics in Atlanta

The concept of deracialization is examined in an election in which all major candidates are black. Citizen characteristics and opinions expressed in a telephone survey are used to predict candidate preference. Findings indicate that race remains an important factor in electoral behavior, even when all candidates are black. The successful candidate, Maynard Jackson, drew support across race and class lines and may be said to have run a deracialized campaign. This research suggests that a clarification of the interaction of race and class and their effects in municipal elections is essential for understanding voting behavior and deracialization in city elections.
Comparative Toxicity of Methyl Bromide Against Ten Nearctic Termite Species (Isoptera: Termopsidae, Kalotermitidae, Rhinotermitidae)

The toxicity of methyl bromide at 27°C was assessed against pseudergates, nymphs, or alates of Zootennopsis angusticollis (Hagen), Tennopsidae; Neotennes castaneus (Bunneister), N. jouteli (Banks), incisitennes snyderi (Light), I. minor (Hagen), and Cryptotennes cavifrons Banks, Kalotennitidae; and Reticulitennes jlavipes (Kollar), R. Hesperus Banks, Prorhinotennes simplex (Hagen), and Coptotennes fonnosanus Shiraki, Rhinotennitidae. Estimates of lethal accumulated doses for 50 and 99% mortality ranged, respectively, from 11.4 and 16.5 for R. hesperus pseudergates to 45.9 and 75.0 mg·h/liter for C. cavifrons pseudergates and nymphs. Alates were more susceptible to methyl bromide than pseudergates or nymphs. These results suggest that current label rate recommendations for methyl bromide are considerably higher than required.
Catalytic control of enzymatic fluorine specificity

The investigation of unique chemical phenotypes has led to the discovery of enzymes with interesting behaviors that allow us to explore unusual function. The organofluorine-producing microbe Streptomyces cattleya has evolved a fluoroacetyl-CoA thioesterase (FlK) that demonstrates a surprisingly high level of discrimination for a single fluorine substituent on its substrate compared with the cellularly abundant hydrogen analog, acetyl-CoA. In this report, we show that the high selectivity of FlK is achieved through catalysis rather than molecular recognition, where deprotonation at the Cα position to form a putative ketene intermediate only occurs on the fluorinated substrate, thereby accelerating the rate of hydrolysis 104-fold compared with the nonfluorinated congener. These studies provide insight into mechanisms of catalytic selectivity in a native system where the existence of two reaction pathways determines substrate rather than product selection.
Accessory molecule regulation of naive CD4 T cell activation

Naive CD4 T cell activation is a complex process involving many steps. T cell receptor (TCR) signals, provided by interaction with peptide/MHC on antigen-presenting cells (APC), control many events associated with activation. The extent of TCR signaling and the magnitude of the T cell response is in turn controlled by accessory molecules on APC, which stabilize T-APC interactions. Full T cell activation additionally requires multiple costimulatory signals, generated upon ligation of T cell coreceptors by accessory molecules, and these lead to IL-2 production, proliferation and differentiation of the naive cell into an effector state. This review summarizes the role played by accessory molecules in naive CD4 activation and discusses how integration of signals from these molecules, with signals from the TCR, may determine the outcome of T-APC interaction. The available data provide explanations for why only APC which express high levels of multiple costimulatory/adhesion molecules, such as dendritic cells and activated B cells, induce efficient naive T cell responses, and suggest that ICAM-1/LFA-1 and B7/CD28 interactions are major pathways used to initiate naive T cell activation.
Prediction of Parachute Line Sail During Lines-First Deployment

A numerical deployment simulation with the capability to predict line sail is presented. A finite-element approach is used in which both canopy and suspension lines are modeled as flexible, distributed-mass structures connected to a finite-mass forebody. The model includes all aspects of the deployment problem, such as suspension line aerodynamics, line ties, .and canopy/deployment bag friction. The model has been verified by comparison with experimental data and used to investigate proposed solutions for a system with a line sail problem.
Missing Y chromosomes in lymph nodes from patients with non-Hodgkin's lymphoma

Five of 86 male patients with non-Hodgkin's lymphoma had chromosomally abnormal clones in their lymph nodes, which involved a missing Y chromosome. The loss of the Y chromosome was confined to the malignant cells when normal cells were present. The patients ranged in age from 41 to 85 years. All five patients had B-cell lymphomas with the histologic subtype diffuse large cell in two patients and immunoblastic, follicular large cell and follicular mixed in a single patient each. The t(14; 18)(q32;q21) chromosome abnormality accompanied the missing Y chromosome in four of the five patients. It appears that Y chromosome loss is one of the secondary abnormalities associated with non-Hodgkin's lymphoma.
A novel flotation column for oily water cleanup

A novel multi-stage loop-flow flotation column (MSTLFLO®) was developed for fine particle separations. The unique design feature of the MSTLFLO column is the use of draft-tubes to achieve multi-stage configuration and minimize back-mixing/entrainment in flotation. As a potential application, the column was studied for its performance in separating emulsified oil from water. The separation efficiency was found to be highly dependent on the unique hydrodynamic conditions provided in the column. The separation kinetic constants were therefore correlated with the hydrodynamic parameters, including gas holdups, Sauter bubble sizes and liquid circulation rates. A classic tank-in-series model was successfully employed in the modeling of the process.
Dissociable musical processing strategies after localized brain damage.

Abstract Brain-damaged patients were asked to judge whether two familiar but lyricless musical phrases were taken from the same or from two different songs. Foils were built into the task so that patients' relative reliance on music's linear sequential properties, on its general mood characteristics, or on its susceptibility to flexible classification could be assessed. The principal results revealed that Broca's aphasics and patients with right anterior insult encountered the greatest difficulty overall in making same song/different song judgments. However, right anterior patients' musical judgments relied almost exclusively on the mood of the phrases but Broca's aphasics' judgments relied on a linear sequential musical processing strategy. These data indicate that strategies for processing musical material can be dissociated following localized cerebral insult.
An HF-Resistant Sample Introduction System for the Inductively Coupled Plasma

A sample introduction system constructed of materials completely resistant to HF was developed for analysis of HF-containing samples. A machined graphite injector tube, polytetrafluoroethylene (PTFE) spray chamber, and cross flow nebulizer containing PTFE capillaries were employed. The arrangement is completely compatible with commercial ICP systems and can be interchanged readily. The nebulizer efficiency and memory effect were studied and compared with a conventional system. Analysis of silicon in commercial HF acid was performed.
The Convergence of the Particle Method for the VLASOV POISSON System with Equally Spaced Initial Data Points

A proof of convergence of particle methods is given for the Vlasov–Poisson system in three dimensions. This proof applies to some classes of initial functions not included in previous analyses of this problem. A semidiscrete problem is considered discretized in space but not in time with equally spaced initial data points. The convergence is proved for initial functions that are two and three times differentiable. Error estimates are obtained for these cases that depend on the two parameters, the interparticle distance and the mollification parameter in the approximate electric field. To gain further insight into the form such error bounds may take some computations are then done on the one dimensional Vlasov–Poisson system. Experimentally determined error bounds are obtained for particle-in-cell methods. Based on the computed error estimates in one dimension some conclusions are drawn regarding the accuracy of the type of error bounds obtained for the system in three dimensions.
Recognizing Excellence in Maternal and Child Health (MCH) Epidemiology: The 2014 National MCH Epidemiology Awards.

Purpose The impact of programs, policies, and practices developed by professionals in the field of maternal and child health (MCH) epidemiology is highlighted biennially by 16 national MCH agencies and organizations, or the Coalition for Excellence in MCH Epidemiology. Description In September 2014, multiple leading agencies in the field of MCH partnered to host the national CityMatCH Leadership and MCH Epidemiology Conference in Phoenix, Arizona. The conference offered opportunities for peer exchange; presentation of new scientific methodologies, programs, and policies; dialogue on changes in the MCH field; and discussion of emerging MCH issues relevant to the work of local, state, and national MCH professionals. During the conference, the National MCH Epidemiology Awards were presented to individuals, teams, institutions, and leaders for significantly contributing to the improved health of women, children, and families. Assessment During the conference, the Coalition presented seven deserving health researchers and research groups with national awards in the areas of advancing knowledge, effective practice, outstanding leadership, young professional achievement, and lifetime achievement. The article highlights the accomplishments of these national-level awardees. Conclusion Recognition of deserving professionals strengthens the field of MCH epidemiology, and sets the standard for exceptional research, mentoring, and practice.
Microcatalytic reactors: Kinetics and mechanisms with isotopic tracers

Pulsed microcatalytic reactors have found extensive application in the petroleum and chemical industries where rapid catalyst screening and evaluation are demanded. Automated, continuous-operation test units allow the accumulation of considerable amounts of data in a minimum of time. The technique is also useful in research where the small pulse size enables one to study “initial” interactions between surface and reactants. In this way, information about many kinetic parameters, such as intrinsic reaction rates, orders, poisoning effects, and catalyst deactivation, can be obtained. Both stable and radioactive isotopic tracers may be used economically in microcatalytic reactors to provide significant mechanistic information which cannot be obtained conveniently by other methods. For example, one can explore the chemical nature and number of active sites, as well as the fate of individual atoms and molecules as they interact with the catalyst. Although the technique may be applied to both “simple” and complex catalytic reaction systems, the discussion will be limited to a review of data obtained from (1) “unimolecular” reactions such as cyclopropane and butene isomerization and cumene dealkylation over the mixed oxides silica-alumina, silica-magnesia, and zeolites and (2) “bimolecular” reactions such as ethylene hydrogenation over alumina. Some of the limitations of microcatalytic reactors will also be given. Les reacteurs microcatalytiques et pulses ont nombre d'applications dans les industries petroliere et chimique ou l'on a besoin d'un classement et d'une evaluation rapides des catalyseurs. Les reacteurs d'essai automatiques et a fonctionnement continu permettent d'accumuler une foule de renseignements en un temps minimum; on peut aussi les utiliser dans le travail de recherche ou les faibles pulsations permettent d'etudier Taction initiate et reciproque entre la surface et les reactifs. Il s'en suit qu'on peut obtenir des renseignements sur un grand nombre de para-metres cinetiques tels que vitesses intrinseques et orders de reaction, effets d'empoisonnement et deactivation du catalyseur. On peut utiliser economiquement dans les reacteurs microcatalytiques des traceurs isotopiques stables et radioactifs pour obtenir des renseignements mecanistiques qu'on ne pourrait se procurer convenablement par d'autres methodes: par exemple, on peut explorer la nature chimique et le nombre des points actifs et decouvrir ce qu'il advient des atonies et molecules individuels lorsqu'ils reagissent sur le catalyseur. Bien qu'on puisse appliquer la methode precitee a des systemes de reaction catalytique a la fois “simples” et complexes, on limite la discussion a une revue des resultats obtenus (1) des reactions a “molecule unique”, telles qui l'isomerisation du cyclopropane et du butene et la dealcoylation sur des oxydes melanges (silice et alumine ou silice et magnesie) et les zeolites, et (2) des reactions a “deux molecules”, telles que l'hydrogenation de l'ethylene sur le l'alumine. On traite aussi de certaines limitations qui affectent les reacteurs microcatalytiques.
Iodine and the “Near” Eradication of Cretinism

The eradication of intellectual disability from iodine deficiency in Western countries is one of the great public health triumphs of 20th-century child health care.1 Yet the problem persists today in many parts of the world.2 This article explores why a strategy so successful in the West has proven difficult to export to certain other contexts and how new kinds of thinking may point the way forward. As recently as the late 19th century, American pediatricians were familiar with the dwarfism and severe mental deficiency associated with the syndrome that had long been called “cretinism”. The 1920 edition of L. Emmett Holt’s3 influential textbook The Diseases of Infancy and Childhood described these children as “dull, placid, and good-natured, rarely troublesome or excitable; and when fifteen or eighteen years old they appear like children of three or four years” (Figure 1). Pediatricians in those times were aware that the short stature and coarse facial features of cretinism could be lessened by the early administration of thyroid extract, with Holt describing a change in the entire appearance of the child and a loss of “the idiotic expression of the features.” However, treatment did not prevent children from developing mental deficiency. FIGURE 1 Images from the 1920 edition of The Diseases of Infancy and Childhood, by L. Emmett Holt: A, A typical cretin at 2½ years old; B, The same patient at 6 years of age, illustrating the effect of thyroid treatment. Prenatal iodine deficiency, and the resulting fetal hypothyroidism that caused cretinism, vanished … Address correspondence to Sana Syed, MD, Children’s Healthcare of Atlanta, 2015 Upper Gate Dr NE, Atlanta, GA 30322. E-mail: sana.syed{at}emory.edu
Stability of certain periodic solutions of a forced system with hysteresis

Abstract Many physical systems exhibit the phenomenon of non-linear hysteresis when the amplitude of oscillation exceeds some small limit.[l] It has been shown in [2] that under certain conditions there are periodic motions of such a system with small forcing which are near the largest periodic motion of the corresponding unforced system. In this paper, conditions for the stability of these periodic motions are derived.
The long and short of money: short-run dynamics within a structural model

Empirical examinations into aggregate money demand functions, generally, incorporate a monetary aggregate as the dependent variable. While this custom may be inefficient, it does not create any new difficulties for estimating the demand function's long-run parameters, as money supply would equal money demand. The short-run estimates, however, are not as fortunate. As the monetary aggregate is a measure of supply and not demand, one needs to tease out the short-run responses associated with money demand changes with those which are associated with monetary supply shocks. The present article, therefore, proposes a more complete representation of monetary sector behaviour and in doing so, finds significant support for the so-called buffer stock money demand models.
Identification and characterization of γ-giardin and the γ-giardin gene from Giardia lamblia

Abstract The giardins are abundant cytoskeletal proteins that range in size from 29–38 kDa and are specific to the ventral disk of the intestinal protozoan parasite Giardia lamblia. The 29-kDa (β and β-1; refs. 8–10) and the 33-kDa (α-1 and α-2; refs. 3 and 7) giardins have been characterized previously. In this paper we extend the analysis of the giardins to include the 38-kDa giardin, which we have named γ-giardin. After purifying γ-giardin by two-dimensional electrophoresis, we raised polyclonal antibodies to the protein and used them to demonstrate that γ-giardin shares at least one epitope with 9 other giardin polypeptides and that it localizes to the ventral disk of the parasite. We also determined an internal peptide sequence of 12 amino acid residues and used this information to construct oligonucleotide probes for the γ-giardin gene. After cloning the gene, we determined the nucleotide sequence of its 933-bp open reading frame and 866 bp of 5′ and 3′ flanking sequence. We found the downstream AGTPuAAPy motif typical of all G. lamblia genes sequenced to date, and determined that the single copy of the γ-giardin gene localizes to the same chromosome or chromosomal cluster as the α-giardins. Finally, we demonstrated by primer extension analysis that γ-giardin transcripts contain a short untranslated leader characteristic of G. lamblia messenger RNAs.
Long-Term Incarceration Impacts and Characteristics of Long-Term Offenders: An Empirical Analysis

The responses long-and short-term inmates make to incarceration and differences in the responses made by distinct subgroups were examined. Prison inmates in three large maximum security institution...
Melanin-based plumage coloration in the house finch is unaffected by coccidial infection.

For most species of birds, ornamental plumage coloration may result from two types of pigments: carotenoids and melanins. Despite the fact that melanin pigments can be synthesized by birds from basic, amino acid precursors, while carotenoids cannot be synthesized by birds and must be ingested, melanin-based plumage coloration and carotenoid-based plumage coloration have often been treated as a single trait in investigations of the function and evolution of plumage coloration. Expression of carotenoid-based coloration is known to be dependent on condition, while the effects of individual condition have not been well-tested for expression of melanin-based coloration. In this study, we experimentally tested the effect of coccidial infection of the intestinal tract of male house finches during moult on expression of melanin-based plumage coloration. Coccidial infection had a significant negative effect on carotenoid-based coloration, but it had no significant effect on melanin-based feather coloration. Unlike carotenoid-based coloration, melanin-based coloration may be cheap to produce, and honesty of melanin-based coloration my require social mediation.
A new 3-D laparoscope in gastrointestinal surgery

This study was set up to compare three-dimensional imaging of a new three-dimensional laparoscope with two-dimensional imaging in the inanimate and clinical settings. In the clinical setting the laparoscope was used in a total of 50 different laparoscopic operations. It provided excellent depth perception, definition, and resolution. The relationships of structures were more easily defined, and instrument manipulation was easier, doing away with the need for “touch and feel” to determine instrument position. Three-D imaging made cannulation of the cystic duct for cholangiography or with a flexible choledochoscope easier.
Leaf area compensation and nutrient interactions in CO2‐enriched seedlings of yellow‐poplar (Liriodendron tulipifera L.)

summary The responses of yellow-poplar (Liriodendron tulipifera L.) seedlings to elevated levels of atmospheric CO2 were investigated to identify attributes governing growth and physiological responses to CO2. Based on the pattern of leaf initiation and nutrient requirements of the species, it was predicted that (1) CO2, enrichment would enhance growth of yellow-poplar seedlings both through accelerated leaf area production and through higher rates of carbon assimilation per unit leaf area; and (2) growth enhancement of yellow-poplar by CO2 enrichment would be reduced by nutrient limitations. The hypotheses were tested in an experiment in which yellow-poplar plants were grown from seed for 24 weeks in controlled-environment chambers. The experimental design comprised three atmospheric CO2 concentrations (371, 493, and 787 cm3m−3), two levels of mineral nutrients (unfertilized or weekly additions of complete nutrient solution), and three harvests (6, 12, and 24 weeks). Plant growth rate, water use, foliar gas exchange, component dry weights, and nutrient contents were measured. Both hypotheses were rejected. Whole-plant dry weight increased similarly with CO2, enrichment in plants provided with additional mineral nutrients and in unfertilized plants, although the fertilized plants grew 10-fold larger. The increase in dry weight resulting from elevated CO2 occurred only in root systems. Although leaves were produced continuously during the experiment, leaf area was slightly reduced in elevated CO2, and the whole-plant growth response was wholly attributable to an increase in carbon assimilation per unit leaf area. Although the compensation between photosynthesis and leaf area reduced the potential growth response to CO2, the reduction in leaf area ratio was associated with a significant increase in water-use efficiency. This unexpected result demonstrated the importance of feedbacks and interactions between resources in shaping the response of a plant to CO2.
Total mixing ratios

The total mixing ratio of an atom, which may be contained in any number of different molecules, is derived as a function of altitude for the earth's mesosphere and stratosphere. It is shown that the total mixing ratio of most atoms is constant; for an escaping gas, such as hydrogen, the ratio decreases with altitude, whereas the mixing ratios of atoms deposited by meteors increase with altitude. The analysis shows that by using total mixing ratios, the individual mixing ratios at a certain altitude can be related to those of another altitude without any restrictions on chemical lifetimes.
The first step on a long path toward normalization

Over the past fi ve years, the US Federal Reserve has been engaged in an aggressive campaign to provide support to a US economy that was badly damaged by the fi nancial crisis and the accompanying Great Recession. The Fed’s efforts have included the massive provision of liquidity to impaired fi nancial markets, the purchase of more than US$3 trillion of long-term securities to ease overall fi nancial conditions, and the issuance of forward guidance about the path of future short-term interest rates in order to lower borrowing costs across the yield curve. Although precise estimates of the effectiveness of these measures remain the subject of ongoing research, there can be little doubt that these policies have contributed to the process of repair and recovery of the US economy. Balance sheet deleveraging by businesses and households and an unwise shift of fi scal policy to a stance of appreciable restraint have weighed heavily on the economy, and the Federal Reserve’s policies have provided a meaningful counterweight against those forces. Accommodative monetary policy has boosted interest-sensitive spending, especially for houses and motor vehicles, and it has lifted household wealth and consumer spending by raising prices for equities and houses. More recently, as the fi scal drag imposed by last year’s cuts in federal spending and increases in taxes has begun to wane, there have been increasing signs that the pace of the economic expansion in the United States is picking up.
Free energies and equilibria of peptide bond hydrolysis and formation

For every n amino acids linked in a protein there are n − 1 peptide bonds. The free energy of peptide bond hydrolysis and formation in aqueous solution defines the equilibrium position between peptide and amino acid hydrolysis products. Yet few experimental values exist. With a minimum of assumptions, this paper deduces the free energies of hydrolysis of a variety of peptide bonds. Formation of a dipeptide from two amino acids is about eight times more difficult than subsequent condensations of an amino acid to a dipeptide or longer chain. Condensation of an amino acid to a peptide of any size is five times more difficult than joining two smaller peptides of at least dipeptide size. Thus in an abiogenesis scenario there is a kind of nucleation in peptide bond formation with the initial condensation of two amino acids to yield a dipeptide more difficult than subsequent condensations to a growing chain. © 1998 John Wiley & Sons, Inc. Biopoly 45: 351–353, 1998
Transient four-wave mixing and optical pulse compression in the femtosecond regime

The transient behavior of parametric-scattering four-wave mixing is investigated experimentally with femtosecond laser pulses. Special emphasis is placed on the measurement of parametric pulse durations and the application of this process to the compression of femtosecond optical pulses. Compression factors up to 1.85 have been achieved, yielding high-power pulses of less than 40-fsec duration.
Accounting for Stock Options: Measuring the Real Cost Through Time

Accounting for stock options is a controversial issue. The FASB recognized that the “intrinsic value” method, which had been used for years, failed to adequately account for the costs involved. To rectify the problem they suggested the use of a “fair value” method. Their proposal met with strong objections from companies, which were concerned with the impact of the proposed standard on their reported profits. Consequently, the board relented and allowed the use of either method. Unfortunately, both the intrinsic value and fair value approaches have deficiencies, particularly in regard to how they measure compensation expense and gains and losses over time. This paper addresses these shortcomings by developing two alternative cost measurement approaches that apply an option‐pricing model on an iterative basis over the life of the option. Both approaches represent specific ways to implement exercise‐date measurement techniques for stock options. The paper argues that both approaches provide more relevant and reliable measures of an option’s cost than either intrinsic or fair value methods.
Predicting the Commercialization Progress of Early-Stage Technologies: An Ex-Ante Analysis

Predicting commercialization progress (CP) for early-stage technologies is critical for funding agencies and private equity investors. This study employed an ex-ante analysis of expert assessments on the future potential of early-stage technologies by a U.S. Department of Defense funded Technology transfer agency. We examined expert assessments of 271 technologies that were considered for funding. We then evaluated subsequent CP of these technologies. Our results indicated that evaluations of technical merit were significantly and positively related to obtaining follow-on grants, license agreements, and partnership alliances, while evaluation of commercial potential was related to obtaining subsequent private equity investment. Evaluation of management team expertise was positively related to future revenue generation, but negatively related to future equity investment, partnership alliances, and license agreements. Meeting established milestones was also related to future commercial success.
Stable configurations of polypeptide chains.

Several configurations of polypeptide chains involving planar amide groups with the dimensions found by experiment for simple substances, and hydrogen bonds between the NH groups and the carbonyl oxygen atoms, have been discovered. One of these structures, the α-helix, with about 3·7 amino-acid residues per turn of the helix, has been assigned to synthetic polypeptides and proteins that give X-ray diagrams of the α-keratin type. The evidence supporting this assignment is reviewed. Other configurations of polypeptide chains, including the γ-helix, three pleated-sheet structures, and the three-chain helical structure proposed for collagen, are described, and evidence bearing on their possible presence in proteins is discussed.
Suppression of Pdx-1 perturbs proinsulin processing, insulin secretion and GLP-1 signalling in INS-1 cells.

Aims/hypothesis Mutations in genes encoding HNF-4α, HNF-1α and IPF-1/Pdx-1 are associated with, respectively, MODY subtypes-1, -3 and -4. Impaired glucose-stimulated insulin secretion is the common primary defect of these monogenic forms of diabetes. A regulatory circuit between these three transcription factors has also been suggested. We aimed to explore how Pdx-1 regulates beta cell function and gene expression patterns.