cssi/SciSciGPT-SciSciNet huggingface dataset:
Do border policies reduce flows of Venezuelan migrants

Conventional wisdom suggests that migration policy has a significant, unidirectional effect on migration, namely, that tough policies slash inflows, while the reverse is true for permissive policie...
Pelvicalyceal Volume and Fluid Temperature Elevation During Laser Lithotripsy.

Background: While high-power laser systems facilitate successful ureteroscopic treatment of larger and more complex stones, they can substantially elevate collecting system fluid temperatures with ...
Characterization of an element resembling an androgen response element (ARE) in the human aldose reductase promoter.

Aldose reductase has been implicated in a number of diabetic complications including background retinopathy (microaneurysms) and cataracts. The formation of microaneurysms is independently related to duration of disease and hyperglycemia, and is found in post-pubertal patients (Murphy et al., 1990). They are thought to be caused by the loss of pericytes resulting from the activity of aldose reductase. The mechanisms regulating the expression of the enzyme in specific tissues and in pathological conditions are unknown.
The significance of the number of periods and period size in 2D photonic crystal waveguides

This work investigates the significance of the number of periods in two-dimensional photonic crystals. Models have been developed to study various photonic crystal properties (Reflection, Photonic crystal band gap). The numbers of photonic crystal periods, length of periods, and material properties have been investigated to determine their effect on the losses in the waveguide. The model focuses on a square period and has been designed to study transmission properties and the effects of period length. A finite difference frequency domain (FDFD) model has also been created to calculate the photonic band structure. Additionally, a simplified study focuses on the transmission of light through photonic crystal layers.
Polarization phenomena of electrons and photons. II: Results for Compton scattering

Synopsis The Compton cross section is given, including all polarization details. The use of the 3-dimensional polarization vectors ξ and ζ, for photons and electrons, makes the results very explicit, so that any specific polarization effect can easily be obtained from the general formula. A special discussion and numerical results are given for the following polarization effects: a The detection of circularly polarized gamma radiation by Compton scattering from magnetized iron. b The production of polarized electron beams by incident circularly polarized gamma radiation. c The production of polarized electron beams by scattering unpolarized gamma radiation from magnetized iron.
Thymidine Incorporation by the Microbial Community of Standing Dead Spartina alterniflora.

Thymidine incorporation by the microbial community on standing dead leaves of Spartina alterniflora did not obey many of the assumptions inherent in the use of the technique in planktonic systems. Incorporation rates of [methly-3H]thymidine were nonsaturable over a wide concentration range (101 to 105 nM). Owing to metabolism by both fungi and bacteria, a major fraction of the radiolabel (mean, 48%) appeared in protein. Extraction of the radiolabeled macromolecules was inefficient, averaging 8.8%. Based on an empirically derived conversion factor, 4 × 1018 cells · mol of thymidine−1, doubling times ranged from 4 to 69 h for the epiphytic bacterial assemblage.
Impact of dissolved organic matter on the desorption and mineralization rates of naphthalene

The persistence of organic contaminants in plant-soil systems will be largely determined by the basic processes controlling bioavailability: desorption and biodegradation. Both processes can be affected by the presence of and variations in dissolved organic matter (DOM). To evaluate potential effects of DOM in surface soil remediation systems, the kinetics of naphthalene desorption from soil and mineralization in soil solution in the presence of DOM were studied in completely mixed batch reactors (CMBRs). Three different DOM solutions were studied. These were obtained from water extraction of two different soils (muck-highly organic and alfalfa field-agricultural) and a third prepared by reconstituting a fulvic acid reference standard purchased commercially. Neither the desorption rate nor equilibrium partitioning of naphthalene was affected by the presence of varying DOM solutions. The effect on mineralization was evaluated based on an evaluation of a first-order rate constant produced by nonlinear regre...
Selective N-Hydroxyhydantoin Carbamate Inhibitors of Mammalian Serine Hydrolases

Serine hydrolase inhibitors, which facilitate enzyme function assignment and are used to treat a range of human disorders, often act by an irreversible mechanism that involves covalent modification of the serine hydrolase catalytic nucleophile. The portion of mammalian serine hydrolases for which selective inhibitors have been developed, however, remains small. Here, we show that N-hydroxyhydantoin (NHH) carbamates are a versatile class of irreversible serine hydrolase inhibitors that can be modified on both the staying (carbamylating) and leaving (NHH) groups to optimize potency and selectivity. Synthesis of a small library of NHH carbamates and screening by competitive activity-based protein profiling furnished selective, in vivo-active inhibitors and tailored activity-based probes for multiple mammalian serine hydrolases, including palmitoyl protein thioesterase 1, mutations of which cause the human disease infantile neuronal ceroid lipofuscinosis.
Night Becomes Day: Carnival, Contested Spaces, and the Black Movement in Bahia

This article details the cultural politics surrounding carnival in Salvador, Bahia, Brazil, between 1995 and 1999, including the experiences and meanings of carnival, the struggle over Afro-Brazilian culture, and wealth generated from carnival. The black movement utilizes carnival as a highly visible site of contestation and protest against racism in Brazil. However, the movement simultaneously struggles with issues of co-optation, especially by African carnival groups, demonstrating the tensions in the interrelationship between culture and politics. Black movement activists’ stories and experiences reveal the micropolitics of the movement and individuals engaged in politics and identity.
Weakly localized bosons

In this paper, we argue that, in two dimensions, the weak localization of bosons, which occurs on the insulating side of the superconductor-insulator transition, is characterized by $\ensuremath{\rho}\ensuremath{\sim}\mathrm{ln}(1/T),$ as compared to $\ensuremath{\sigma}\ensuremath{\sim}\mathrm{ln}T$ for fermions. This unconventional behavior is tied to the diffusion pole of the delocalized (uncondensed) vortices.
Angiotensin II: An Intraovarian Regulatory Peptide

Mammalian ovarian follicles contain the enzymes and prohormones necessary to elaborate the active octapeptide hormone angiotensin II. In the rat ovary, angiotensin II receptors are located primarily in the theca interna and granulosa cell layers of a discrete subpopulation of follicles. Angiotensin II stimulates both androgen and estrogen secretion from rat ovarian slices. These findings suggest an autocrine/paracrine role for angiotensin II in ovarian follicular development.
Oregon's physician-assisted suicide law. An alternative positive viewpoint.

IN A commentary on Oregon's physician-assisted suicide law Emanuel and Daniels1raise many of their concerns about the Oregon Death With Dignity Act, and see its safeguards as inadequate. Much of the information they provide can be perceived differently. I refer to the provisions of the Act in proposing different interpretations, and I reach different conclusions about the adequacy of its safeguards. BACKGROUND TO OREGON DEATH WITH DIGNITY ACT The Act is a response to a growing awareness on the part of the public and of the medical profession that alternatives to institutionalized dying are needed for terminally ill competent patients, and that lawful consideration of physician-assisted suicide (aid in dying) is both ethical and appropriate. Public opinion polls have shown progressively increasing public support of physician-assisted suicide.2In several recent articles3-5surveys of physicians have demonstrated that many physicians believe that physician-assisted suicide is ethical and
Observations on the occurrence of atrial fibrillation in paroxysmal supraventricular tachycardia

Paroxysmal supraventricular tachycardia (PSVT) and atrial fibrillation (AF) are both supraventricular arrhythmias, but their mechanisms are completely different. This study determines the incidence of symptomatic AF in a group of patients followed closely during routine outpatient care for PSVT. Thirty-nine patients with PSVT were followed for up to 4 years using telephone transmission of the electrocardiogram to document symptomatic arrhythmias. The cumulative proportion of patients who had AF was calculated using the Kaplan-Meier life-table method. In addition, we examined the importance of clinical variables traditionally believed to influence the occurrence of AF. The cumulative proportion of patients who had AF during follow-up was 13% at 3 months, 16% at 6 months, 22% at 1 year and 29% at 2 years. In most patients the start of AF was documented during an attack of PSVT rather than de novo as another primary arrhythmia. PSVT occurred significantly earlier during an observation period without treatment in patients in whom AF developed (p = 0.03). The occurrence of AF was not related to age, number of years of PSVT, heart rate during tachycardia or coexistent heart disease.
Comparison of the Signaling Abilities of the Cytoplasmic Domains of the Insulin Receptor and the Insulin Receptor-Related Receptor in 3T3-L1 Adipocytes

In the present work a chimeric receptor containing the intracellular domain of the insulin receptor-related receptor (IRR) and the extracellular domain of the colony stimulating factor-1 (CSF-1) receptor was expressed in 3T3-L1 adipocytes and compared with the parallel chimeric receptor containing the cytoplasmic domain of the insulin receptor (IR). Both chimeric receptors exhibited CSF-stimulated tyrosine kinase activity when assayed in vitro after in vivo activation comparable to that of the endogenous IR present in these cells. No cross-activation of the expressed chimeric and endogenous receptors was observed. The cytoplasmic domain of the IRR was found to 1) mediate activation of the Ser/Thr kinase Akt/PKB, 2) stimulate glucose uptake, 3) inhibit lipolysis, and 4) stimulate glycogen synthase, all with a potency comparable to those of the expressed CSF-1R/IR chimera and the endogenous insulin receptors. These results indicate that despite the extensive differences in sequence between the cytoplasmic domains of the IRR and IR, the elements required for insulin-specific responses have been conserved in this distinct member of the insulin receptor family.
Cadmium analysis of dried milk by pulse polarographic techniques.

Abstract The applicability of differential pulse anodic stripping voltammetry for the determination of little cadmium in milk has been demonstrated. Sample preparation included dry ashing and dissolving the ash in hydrochloric acid. Highest recovery of cadmium was with ashing temperatures between 500 and 540 C. Cadmium recovery was 94% on milk powder spiked at 10 parts per billion (ppb) and 86% on powder spiked at 2 ppb. Samples of foam spray-dried skim milk and freeze-dried whole milk contained less than 3 ppb cadmium on a dry weight basis.
Affects of Task Difficulty on Target Guidance Using Auditory and Tactile Cues

Two dual-task experiments were conducted to compare guidance systems using tactile and/or auditory cues. The tasks were a targeting task and a shadowing task. In experiment one, the guidance cues matched the location of the targets actual position in space. In two, the cue to move left originated in front while the cue to move right originated from behind the subject. This was done to assess how increasing the difficulty of processing the cues affected performance. Little difference was found between the two systems on the targeting task in experiment one, but in experiment two the tactile system consistently outperformed the auditory system. This suggests that when processing modes are different, using the same sensory channel for two tasks has little affect on performance, but when processing difficulty is increased, using separate channels results in better performance.
Measurement of Phonated Intervals During Four Fluency-Inducing Conditions

Purpose Previous investigations of persons who stutter have demonstrated changes in vocalization variables during fluency-inducing conditions (FICs). A series of studies has also shown that a reduc...
A Stock Location Model for Dual Address Order Picking Systems

Abstract A model is formulated to evaluate alternative stock levels and item locations for dedicated storage warehouses where storage and retrieval transactions are interleaved to economize on travel of the order picking vehicle. The model can be used to measure the order picking and inventory cost effects of warehouse layouts representing alternatives to application of economic lot sizing and cube per order index storage assignment. A simple, sequential search heuristic is proposed for generating such alternative warehouse layouts and applied to a sample problem.
Organizational decline, extended work life and implications for faculty planning☆

Abstract Following several decades of expansion that facilitated growth and development of opportunities for faculty, projections of declining enrollment of students and postponed retirement of senior faculty have created a renewed interest in human-resource planning for universities. This paper proposes a planning framework that focuses in particular on the consequences of exogenous changes for internal faculty promotions and draws attention to tradeoffs among potentially competing objectives. A goalprogramming variation is applied to a fractional flow model of organizational mobility, and is illustrated by simulation of five-year planning scenarios at a large liberal-arts college.
A reflecting microscope for infrared spectrometry.

A reflecting microscope designed for use in front of the entrance slit of a Perkin-Elmer single-beam infrared spectrometer is described. It is shown that the heating effect of the condensed beam on the sample is not significant except in the case of compounds which absorb strongly in the 3-micron region of the spectrum, and then only if the sample is unsupported. The instrument is being applied to the study of small quantities of material in solution and to single crystals. Spectra adequate for identification purposes may be obtained from less than 10 micrograms of a sample in solution. The minimum sample size is limited at present by the technique of sample transfer and if this can be improved, spectra could be obtained with about 1 microgram. Preliminary results using polarized radiation in the study of fatty acid crystals are also presented.
p-Toluenesulfonyldiazoacetates: Reagents for photoaffinity labeling

Abstract p -Toluenesulfonyldiazoacetyl chloride and p -nitrophenyl p -toluenesulfonyldiazoacetate have been prepared and offer potential advantages as reagents for photoaffinity labeling. (i) The extinction coefficient for the sulfonyldiazo compounds at 370 nm is about 10 times that for the long wavelength absorption of other diazoesters; this absorption permits reasonably rapid photolysis in the presence of compounds that are destroyed by short wavelength uv radiation. (ii) The two derivatives named above are stable thermally; furthermore, since sulfonyldiazoesters are stable to acid and to weak base, photoaffinity labeling can be conducted over a wide range of pH. (iii) Photolysis of ordinary (i.e., oxygen) esters of sulfonyldiazo compounds in methanol or cyclohexane leads to insertion into the solvent to the exclusion of Wolff rearrangement; photolysis of thioesters at 350 nm in methanol gives about 25% insertion into solvent, accompanied by about 75% Wolff rearrangement; in contrast, photolysis of most thioesters of diazo derivatives leads exclusively to Wolff rearrangement
Radiographic pseudofracture of the Medtronic bipolar polyurethane pacing lead

with consequent prosthesis-patient mismatch3; in fact, the prosthetic aortic valve index at operation, calculated retrospectively, was 1.5 cm2/m2. Significant transaortic systolic gradients have been reported postoperatively with small-sized Hancock xenografts.’ In the present case stenosis was made worse by fibrous tissue overgrowth on the cusps, which is observed mainly on the mitral porcine prostheses,’ and by central impingement of the valve prongs. The latter has recently been recognized as a cause of hemolysis5 and thrombus formation: both of which were absent in our case. Currently, concern exists that the standard orifice Hancock valve may not be a suitable substitute for the native aortic valve in the presence of a narrowed anulus if surgical enlargement of the latter is not performed.7 The case herein reported provides evidence that the already unfavorable ratio of internal to external diameter of small-sized Hancock valves may be worsened, even in the absence of structural changes of the cusps, by fibrous tissue overgrowth and inward bending of the struts, an association previously unreported.
Operationalizing the Construct of Friendship among Children: A Psychometric Comparison of Sociometric-Based Definitional Methodologies

Peer relations researchers generally agree that friendship involves a close, mutual, dyadic relationship. However, the lack of consensus on how to operationalize this construct has limited our understanding of the role of friendship in social adjustment. The present study directly compared the psychometric properties (i.e., number of friendships identified, concordances, and stability) of the five major different definitions of friendship used in the literature. Fourth- and fifth-grade students (N = 90) completed a battery of sociometric measures at two different times separated by eight weeks. Friendship dyads were then identified using the following definitional criteria: (1) mutual positive nominations; (2) mutal high ratings (i.e., 4 or 5 on a five-point Likert-type scale); (3) one positive nomination reciprocated by a rating of 5; (4) one positive nomination and mutual high ratings; and (5) one positive nomination and mutual ratings averaging at least 4. Frequency and concordance analyses indicated differences across the five definitions. In addition, the friendships identified by each of the five definitions were similarly moderate in their stability. Explanations for, and the possible implications of, these differences are discussed.
Color Face Plots for Displaying Product Performance

With color face plots, red eyes don't necessarily indicate lack of sleep. In this study they mean an IC transistor array variable is outside its design limits.
Techniques for molecular beam epitaxy of multiple-wavelength vertical-cavity laser arrays

New techniques are proposed for engineering the lateral growth rate profile in molecular beam epitaxy for fabrication of arrays of vertical-cavity lasers operating at different wavelengths. A previous study of the use of flux masks to achieve uniform profiles is extended to the case of intentionally nonuniform profiles along the radial direction. It is further suggested that substrate rotation at variable angular velocities can produce intentionally nonuniform profiles in the polar direction.
Hydrogen absorption by the ternary borides RCo4B (R ≡ La, Pr, Sm) and RNi4B (R ≡ Ca, La, Pr)

Abstract The hydrogen absorption properties of the ordered hexagonal ternary borides RCo4B (R ≡ La, Pr, Sm) and RNi4B (R ≡ Ca, La, Pr) were investigated in order to obtain information about the parameters leading to hydride formation in CaCu5-type intermetallics. RCo4B compounds crystallize with the CeCo4B structure and absorb about 4.5 hydrogen atoms per formula unit. Multiplateau behavior indicates that at least three distinct hydride phases exist around room temperature in the pressure range 0–100 atm. In contrast with the RCo5Hz phases, which are orthorhombic for z > 1, RCo4BHz phases exhibit an orthorhombic structure only in the α phase region (z ⩽ 1), with all higher hydrides reverting to the hexagonal structure. CaNi4B, which also crystallizes with the CeCo4B structure, absorbs 3.2 hydrogen atoms per formula unit at 100 atm and 324 K. The other RNi4B compounds produce X-ray powder patterns which are similar to CeCo4B-type patterns but which exhibit several anomalies. In the case of LaNi4B, singlecrystal studies confirm that a long-period superstructure extends along the basal plane directions. The RNi4 (R ≡ La, Pr) ternaries show a maximum hydrogen uptake of 1.5 hydrogen atoms at room temperature in the pressure range 0–100 atm. This appears to indicate that only built1 2 R in the formula RNi4B is active in absorbing hydrogen (according to the subunit built1 2 RH 3 ). It is assumed that the R which is active in bonding with hydrogen in these latter materials is situated in the R-T plane, while the R in the R-B plane is inactive in this respect. Models for hydrogen site occupancy in the RCo4B hydrides are proposed on the basis of crystallographic considerations.
Intermolecular dipole-dipole relaxation of (129)Xe dissolved in water.

Intermolecular (129)Xe-(1)H nuclear Overhauser effects and (129)Xe longitudinal relaxation time measurements were used to demonstrate that the dipole-dipole coupling is the dominant relaxation mechanism for (129)Xe in water, at room temperature. (129)Xe-(1)H cross-relaxation rates were derived to be sigma(XeH) approximately 3.2 +/- 0.3 x 10(-3) s(-1), independent of xenon pressure (in the range of 1-10 bar) and of the presence of oxygen. Corresponding xenon-proton internuclear distances were calculated to be 2.69 +/- 0.12 A. Using the magnitude of the dipole-dipole coupling and the spin density ratio between dissolved xenon and bulk water, it is estimated that (129)Xe-(1)H spin polarization-induced nuclear Overhauser effects would yield little net proton signal enhancement in water.
On the Applicability of Speaker Diarization to Audio Indexing of Non-Speech and Mixed Non-Speech/Speech Video Soundtracks

A video's soundtrack is usually highly correlated to its content. Hence, audio-based techniques have recently emerged as a means for video concept detection complementary to visual analysis. Most state-of-the-art approaches rely on manual definition of predefined sound concepts such as "ngine sounds," "utdoor/indoor sounds." These approaches come with three major drawbacks: manual definitions do not scale as they are highly domain-dependent, manual definitions are highly subjective with respect to annotators and a large part of the audio content is omitted since the predefined concepts are usually found only in a fraction of the soundtrack. This paper explores how unsupervised audio segmentation systems like speaker diarization can be adapted to automatically identify low-level sound concepts similar to annotator defined concepts and how these concepts can be used for audio indexing. Speaker diarization systems are designed to answer the question "ho spoke when?"by finding segments in an audio stream that exhibit similar properties in feature space, i.e., sound similar. Using a diarization system, all the content of an audio file is analyzed and similar sounds are clustered. This article provides an in-depth analysis on the statistic properties of similar acoustic segments identified by the diarization system in a predefined document set and the theoretical fitness of this approach to discern one document class from another. It also discusses how diarization can be tuned in order to better reflect the acoustic properties of general sounds as opposed to speech and introduces a proof-of-concept system for multimedia event classification working with diarization-based indexing.
Optimal isolation and xeno-free culture conditions for limbal stem cell function.

PURPOSE To preserve limbal stem cell (LSC) function in vitro with xenobiotic-free culture conditions. METHODS Limbal epithelial cells were isolated from 139 donors using 15 variations of three dissociation solutions. All culture conditions were compared to the baseline condition of murine 3T3-J3 feeders with xenobiotic (Xeno) keratinocyte growth medium at 20% O2. Five Xeno and Xeno-free media with increasing concentrations of calcium and epidermal growth factor (EGF) were evaluated at 5%, 14%, and 20% O2. Human MRC-5, dermal (fetal, neonatal, or adult), and limbal stromal fibroblasts were compared. Statistical analysis was performed on the number of maximum serial weekly passages, percentage of aborted colonies, colony-forming efficiency (CFE), p63α(bright) cells, and RT-PCR ratio of p63α/K12. Immunocytochemistry and RT-PCR for p63α, ABCG2, Bmi1, C/EBPδ , K12, and MUC1 were performed to evaluate phenotype. RESULTS Dispase/TrypLE was the isolation method that consistently showed the best yield, viability, and CFE. On 3T3-J2 feeders, Xeno-free medium with calcium 0.1 mM and EGF 10 ng/mL at 20% O2 supported more passages with equivalent percentage of aborted colonies, p63α(bright) cells, and p63α/K12 RT-PCR ratio compared to baseline Xeno-media. With this Xeno-free medium, MRC-5 feeders showed the best performance, followed by fetal, neonatal, adult HDF, and limbal fibroblasts. MRC-5 feeders supported serial passages with sustained high expression of progenitor cell markers at levels as robust as the baseline condition without significant difference between 20% and 5% O2. CONCLUSIONS The LSC function can be maintained in vitro under appropriate Xeno-free conditions.
Reliability of Hamming code transmission versus error probability on message bits

Abstract The paper presents an algorithm for the determination of the reliability of Hamming Code transmission against the error probability on message bits incurred during transmission. It establishes that Hamming Code is effective as long as the error probability of transmission line is less than 3%. The accuracy of Hamming Code drops to 90% when the error probability of the line is 8%. The algorithm is useful in adaptive communication circuits and is suitable for VLSI implementation.
PENAL REFORM AND THE STABILITY OF PRISON ADAPTIVE MODES

ABSTRACT A dramatic shift in penal philosophy has occurred over the past thirty-years. Incapacitation and punishment have effectively replaced the rehabilitative goals of mid-20th century corrections. To assess how this change has affected the day-to-day lives of inmates, face-to-face interviews with men currently incarcerated in a maximum security Missouri prison, as well as historical accounts of “doing time,” are used. Findings show that past accounts of doing time show striking similarity to modern day explanations of everyday life in prison. Results lead one to call into question the impact penal ideology, whatever it may be, has on the experience of doing time in U.S. prisons.
Selection for ryegrass genotypes with tolerance to aluminum toxicity.

Abstract This study reports on a procedure where ryegrass (Lolium multiflorum Lam.) varieties are screened for tolerance to aluminum toxicity. The procedure utilized was a solution‐paper method where seedlings were grown on filter paper which transported nutrient solution from a reservoir. Mean root length for genotypes was the character utilized to determine tolerance to aluminum toxicity. Ryegrass genotypes were subjected to [Al] between 0 to 8 mM with the most useful concenrations being from 2 to 4 mM. Genotypes which demonstrated some tolerance to higher [Al] were North American Plant Breeders R. 0051, ‘Aubade’, ‘Urbana’, Fla 1977B, ‘Tetragulf, Mommersteeg Lmw 96. Considerable variation in root length due to genotypic effect tended to obscure the [Al] effect. The relative rankings of root growth ratios of 4 mM [Al] to 2 mM [Al] tolerance of ryegrass cultivars is questionable. Further work to establish a more reliable screening technique for this specie needs to be undertaken.
3D virtual colonoscopy with real-time volume rendering

In our previous work, we developed a virtual colonoscopy system on a high-end 16-processor SGI Challenge with an expensive hardware graphics accelerator. The goal of this work is to port the system to a low cost PC in order to increase its availability for mass screening. Recently, Mitsubishi Electric has developed a volume-rendering PC board, called VolumePro, which includes 128 MB of RAM and vg500 rendering chip. The vg500 chip, based on Cube-4 technology, can render a 256 3 volume at 30 frames per second. High image quality of volume rendering inside the colon is guaranteed by the full lighting model and 3D interpolation supported by the vg500 chip. However, the VolumePro board is lacking some features required by our interactive colon navigation. First, VolumePro currently does not support perspective projection which is paramount for interior colon navigation. Second, the patient colon data is usually much larger than 256 3 and cannot be rendered in real-time. In this paper, we present our solutions to these problems, including simulated perspective projection and axis aligned boxing techniques, and demonstrate the high performance of our virtual colonoscopy system on low cost PCs.
Inhibition of phenol sulfotransferase by pyridoxal phosphate.

Abstract The biologically abundant cofactor, pyridoxal-5-phosphate (PLP), is a potent inhibitor of bovine phenol (aryl) sulfotransferase (PST). Preincubation of purified enzyme with as little as 1 μM PLP decreased PST activity by 50%. Excess 2-naphthol protected PST from inactivation by PLP, whereas 2-naphthyl sulfate and PAPS were not protective. Although PLP inhibition was apparently competitive with 2-naphthol, a steady-state kinetic Ki value could not be measured due to non-linear Lineweaver-Burk plots in the presence of the inhibitor. Kinetic progress curves revealed that this was due to progressive loss of activity during catalysis. The kinetics of inactivation of PST by PLP were pseudofirst-order and exhibited saturation. The derived KI value for the binding of PLP to PST in the initial reversible step was 23 μM, with a maximal rate of inactivation of 0.077 min−1. Absorbance spectra of the PST/PLP complex indicated the formation of a Schiff base conjugate, and this is consistent with decreased electrophoretic mobility of the protein-PLP adduct in the presence of dodecyl sulfate only after reduction with borohydride. These results point to the possible regulation of an important detoxification enzyme by a ubiquitous cofactor.
The Import-Export Paradigm for High-Quality College Courses: An Answer to Tuition's Through-the-Roof Cost Spiral?

Three new free Stanford online courses drew 300,000 applicants in the fall semester of 2011. Might very high-quality courses with the best streaming lectures, student aids, exams, quizzes, mentoring, and so on facilitate an import export approach to e-learning? Here, the author examines a significant and increasingly troubling problem - the university structure's inability to achieve unit cost reductions through e-learning interventions.
The Relationship of Performance in Professional Education Courses To National Teacher Examinations Scores

Scores on the National Teacher Examinations subtest in profes sional education for 55 secondary education majors were correlated with their grades in courses in educational psychology, secondary methods, and test and measurement. Findings revealed that differ ences existed in the strength of the relationships for males and fe males, but combining the subgroups resulted in stronger correlations for each of the three courses.
The role of low-bandwidth telemedicine in surgical prescreening

Abstract Purpose: Low-bandwidth, Internet-based telemedicine is an inexpensive technology that could help deliver heath care in medically underserved areas. The purpose of this study was to evaluate the usefulness of low-bandwidth telemedicine in remote surgical evaluation. Methods: A group of surgeons and nurses traveled to Mombasa, Kenya to provide surgical assistance at the Coast Province General Hospital (CPGH). Before the visit of the surgical team, surgeons evaluated patients via low-bandwidth telemedicine. Prescreening was performed through use of an Internet-based desktop computer system that was supported technically by the Virginia Commonwealth University (VCU) Medical Informatics and Technology Applications Consortium (MITAC) telemedicine laboratory. Surgical patients were evaluated remotely regarding appropriateness of surgical intervention by reviewing e-mails that included the patient's age, history, physical examination, digital images of the patient, and digital images of pertinent radiographs. Results: Fifty-one patients, including 7 pediatric patients, were prescreened. Thirty-three of the 51 patients (65%) were deemed inappropriate for surgery before this trip because of advanced disease or absence of necessary local medical resources. Of the 18 patients determined to be appropriate candidates for surgery by remote prescreening, 18 (100%) were operated on successfully during the relief effort. Sixty patients including 9 (15%) pediatric patients underwent surgery over the course of 5 days in CPGH. Pediatric cases included various laparoscopic, oncologic, and soft tissue reconstruction. Conclusions: Low-bandwidth, Internet-based telemedicine is a cost-effective technology that can efficiently and effectively prescreen surgical patients in remote areas.
Kinetics of N2+ and N+ reactions with Mo AT ⩽ 100 eV impact energies

Abstract The kinetics of nitridation of polycrystalline Mo by N2+ and N+ have been investigated in the 7.5–100 eV impact energy range. Auger electron spectroscopy has been used to monitor the nitride growth as a function of ion fluence and energy for both N2+ and N+. Bi-exponential nitride concentration versus dose curves are typical of this system. These data are interpreted within a proposed model which employs both surface and subsurface nitrogen binding sites and incorpo- rates sputtering and bombardment induced transport between the two layers. Fitting this model to the data yields apparent reaction cross sections σ and the extent of nitridation ΔN. Two measures of initial capture probability, (1) the experimental initial slope and (2) the product σΔN, are used to characterize reactivity.
Implementation of 3-Port Condensing Wave Rotors in R718 Cycles

The use of a novel 3-port condensing wave rotor is suggested to enhance the turbocompression in a refrigeration cycle that works only with water (R718) as a refrigerant. Although the implementation of such a wave rotor essentially reduces the size and cost of R718 units, their efficiency may also be increased. The condensing wave rotor employs pressurized water to pressurize, desuperheat, and condense the refrigerant vapor, all in one dynamic process. The underlying phenomena of flash evaporation, shock wave compression, desuperheating, and condensation inside the wave rotor channels are described in a wave and phase-change diagram. The thermodynamic process is shown in pressure-enthalpy and temperature-entropy diagrams. Based on the described thermodynamic model, a computer program was generated to evaluate the performance of R718 baseline and wave-rotor-enhanced cycles. The effect of some key parameters on the performance enhancement is demonstrated as an aid for optimization. A performance map summarizes the findings. It shows optimum wave rotor pressure ratio and maximum relative performance improvement of R718 cycles by using the 3-port condensing wave rotor.
Embedded piezoceramics in composites for damage sensing and mitigation : design issues

The use of embedded piezoceramic elements in composite structures provides a simultaneous sensing and actuation capability that has applications in the problem of damage sensing and mitigation. The present paper describes an approach wherein strain readings from embedded sensors can be used to determine the state of the structure. The sensor elements can also function as actuators, and once a loss in structural integrity is established, compensatory strains can be induced in the embedded elements through actuation to control the growth of damage by redistribution of loads around the critical region. Since real-time response is critical for both damage sensing and mitigation, the approach studied is one based on using trained neural networks to establish the desired functional relations. Both the sensing operation and any required actuation is shown to benefit from an optimal placement of the piezoceramic elements in the structure. This design problem is formulated as a nonlinear optimization problem, which includes a mix of continuous, integer, and discrete design variables. A genetic algorithm based optimization strategy is used, where computational expediency requires the use of global function approximations. The approach is implemented in the design of composite beam structures with delamination.
Magnetocrystalline anisotropy in a single crystal of CeNiGe 2

We report measurements on single crystals of orthorhombic ${\mathrm{CeNiGe}}_{2},$ which is found to exhibit highly anisotropic magnetic and transport properties. The magnetization ratio $M(H\ensuremath{\parallel}b)/M(H\ensuremath{\perp}b)$ at 2 K is observed to be about 18 at 4 T and the electrical resistivity ratio ${\ensuremath{\rho}}_{\ensuremath{\parallel}b}/{\ensuremath{\rho}}_{\ensuremath{\perp}b}$ is about 70 at room temperature. It is confirmed that ${\mathrm{CeNiGe}}_{2}$ undergoes a two-step antiferromagnetic transition at 4 and 3 K, as reported for polycrystalline samples. The application of magnetic field along the b axis (the easy magnetization axis) stabilizes a ferromagnetic correlation between the Ce ions and enhances the hopping of carriers. This results in large negative magnetoresistance along the b axis.
The effects of filiform appendage removal on semen collection in the ram.

Abstract The effects of removal of the filiform appendage and the type of collection cone used (polyethylene, rubber, Teflon) on the quantity and quality of semen collected from rams were examined. A total of 182 semen collections from six rams (three appendage-intact and three appendage-amputated rams) were utilized in the study. Observations of ejaculated semen distribution and drainage patterns indicated differences between appendage-intact and appendage-amputated rams. A larger volume of semen and a higher number of spermatozoa were collected from amputated than from intact rams (P 0.05) on initial motility, thermal stress resistance, or morphology of spermatozoa, regardless of the type of collection cone used. Spermatozoa retained on collection cone surfaces were more sensitive to thermal stress (P 0.05). Thus, filiform appendage removal increases ram semen collection efficiency while maintaining semen quality.
Regulatory Role of Parasites: Impact on Host Population Shifts with Resource Availability

Effects of infections by the ciliate Lambornella clarki on larval populations of its mosquito host Aedes sierrensis were examined in laboratory and field studies. When host populations developed with sufficient food, mortality from parasites was additive and reduced the number of emerging mosquitoes. For food-limited populations, mortality was compensatory or depensatory; emerging adults were as or more abundant with higher average fitness than those from uninfected control populations. When nutrients were scarce, parasitic infections relaxed larval competition and increased per capita food by reducing host abundance. Food limitation altered larval feeding behavior, reducing horizontal transmission and subsequent mortality from parasitism.
Relay Reactions That Trap Organometallic Intermediates

In 1968, Richard Heck reported (in seven remarkable consecutive papers) on palladium addition and coupling reactions that create new carbon-carbon bonds ( 1 – 7 ). These reactions and many variants became known as the Mizoroki-Heck reaction, and their use in chemical synthesis (especially of complex natural products) greatly reduced the number of reaction steps needed compared to traditional uncatalyzed reactions. Through the careful use of different transition metals, substrate partners, reaction conditions, and ligands coordinated to the transition metal, chemists can now control product formation, both where a reagent reacts on a molecule (regiochemistry) and how it reacts in a three-dimensional sense (stereochemistry). What has been rare is to combine the formation of a desired bond with the refunctionalization of the molecule at a remote site. On page 1455 of this issue, Werner et al. ( 8 ) report a stereoselective Heck reaction in which not only are the regiochemistry and stereochemistry of the reaction controlled, but a ketone is formed several bonds away through a series of relay of reactions down the substrate chain.
Sublingual Isosorbide Dinitrate Therapy Versus Sublingual Placebo in Angina Pectoris

A double-blind crossover study comparing the effects of 5 mg of isosorbide dinitrate given sublingually four times daily for 4 weeks to those of a placebo also administered sublingually four times daily for 4 weeks was performed on 20 male patients with classical exertional angina pectoris due to coronary artery disease. Isosorbide dinitrate, compared to placebo, significantly reduced the number of anginal episodes requiring nitroglycerin in only one of 17 patients (6%), did not significantly improve exercise tolerance in any of 17 patients, and did not improve the resting or exercise electrocardiograms in any of 17 patients. Isosorbide dinitrate produced headaches in 12 of 19 patients (63%), and two of these patients (11%) were unable to tolerate the drug. Isosorbide dinitrate administered sublingually is no more effective than placebo in treating angina pectoris.
Regulatory Influence and the Imperative of Innovation in Identity and Access Management

In an effort to protect end users from identity theft, policy makers have enacted numerous regulations that require organizations to acquire identity and access management IAM technologies. In this paper, the authors develop and validate a conceptual framework that captures the unique characteristics of information security regulations and their impact on demand for IAM technologies, and the innovation and market value of IAM firms. Using paired two-sample for means t-tests and the Chow test, the authors demonstrate that the annual changes in sales of IAM firms from 1998 to 2008 are higher than those of other information technology IT firms around the time that information security regulations were enacted. The vector autoregression analyses show that IAM innovation is demand-driven, consistent with Schmookler's "demand-pull" hypothesis, and has been positively valued by stock market investors. As such, our results demonstrate how policy makers can stimulate innovation and increase shareholder wealth by regulating IT consumers.
A thermoresponsive hydrogel poly(N-isopropylacrylamide) micropatterning method using microfluidic techniques

Poly(N-isopropylacrylamide) (PNIPAAm) is a thermoresponsive hydrogel that has been widely used in various biomedical applications, including tissue engineering. Making PNIPAAm into a microscale structure is an effective method of increasing its thermoresponsiveness and modulating surface properties compared to bulk PNIPAAm. The commonly used method of direct photolithography combined with a photomask is challenging in creating pure PNIPAAm patterns smaller than 10 µm. Also, each time when there is a need to change the sizes of resulting PNIPAAm patterns, a new photomask is required. Here, a microfluidically controlled micropatterning method utilizing hydrophilic spots on a hydrophobic substrate was developed to create pure PNIPAAm microstructures. This method enabled the fabrication of pure PNIPAAm microstructures with a wide range of sizes from 70 µm to sub-10 µm out of the same substrate preparation by simply varying the flow speed of the hydrogel precursor solution through a microfluidic channel. Hydrogel microstructures with diameters of 12 to 59% of the hydrophilic pattern diameters were successfully fabricated using this fabrication scheme. The smallest hydrogel pattern fabricated using this method was 2.3 µm in diameter using a 5 µm diameter hydrophilic pattern at a flow speed of 100 mm s−1. This simple and versatile fabrication scheme could be an ideal method for creating large arrays of hydrogel micropatterns with varying sizes.
Conducting psychotherapy around the globe: orientation and introduction.

Psychology has become a worldwide science and profession. A number of international associations sponsor meetings and draw together psychologists from around the globe. Psychology and psychotherapy also vary considerably from country to country. Educational systems, licensing patterns, and practice parameters differ in different health service delivery systems depending on the history and policies of the particular country. This issue contains invited articles by psychologists, from a wide sample of countries, who describe the nature of psychotherapy practice in their respective countries and its application to the hypothetical case of Mrs. A. The authors place the case in the cultural context Mrs. A might encounter in their country. © 2007 Wiley Periodicals, Inc. J Clin Psychol: In Session 63: 707–711, 2007.
A metacognitive learning cycle: A better warranty for student understanding?

The Science Curriculum Improvement Study Learning Cycle provides opportunities for students to reveal their science ideas, but no formal, structured opportunities exist for students to reflect on their science ideas. This study proposes a revised learning cycle model, termed the Metacognitive Learning Cycle, which emphasizes formal opportunities for teachers and students to talk about their science ideas. Working collaboratively, the researcher and a seventh-grade science teacher developed a 3-month ecology unit based on the revised model. Two science classrooms studied identical ecology content using different pedagogical orientations. One class was taught using the SCIS approach and one was taught using the metacognitive approach. Only in the metacognitive classroom were students asked to reveal their science ideas and to discuss the status of their conceptions throughout the instruction. Results showed that students in the metacognitive classroom did not gain a greater content knowledge of ecology, but they did experience more permanent restructuring of their ecology understandings. © 2000 John Wiley & Sons, Inc. Sci Ed84:486–506, 2000.
Influence of ammonia and arginine upon orotic acid and urea biosynthesis in human liver

Abstract The in vitro rates of orotic acid and urea biosynthesis were determined in human liver obtained by biopsy. Increasing the quantity of ammonia added to the incubation medium from 0.0 mM to 5.0 mM resulted in an approximate 200% increase in liver urea biosynthesis and about a doubling of orotate biosynthesis. Supplementation of arginine to the medium doubled the rate of urea biosynthesis above that at saturated ammonia (5.0 mM) concentrations. Arginine supplementation to a medium containing 5mM ammonia reduced the rate of liver orotate biosynthesis to rates occuring with no supplemental ammonia. These studies show that the interrelationship between urea cycle activity and pyrimidine biosynthesis are similar metabolically to those observed previously in other mammals.
Expanding genome capacity via RNA editing.

Abstract RNA editing, which results in the creation of RNA molecules that differ from the template from which they were made, is a highly specific process. Alterations include converting one base to another, removal of one nucleotide and substitution of another, deletion of encoded residues, and insertion of non-templated nucleotides. Such changes have marked effects on gene expression, ranging from defined amino acid changes to the de novo creation of entire open reading frames. Editing can be regulated in a developmental or tissue-specific manner, and is likely to play a role in the etiology of human disease. To cite this article: J.M. Gott, C. R. Biologies 326 (2003).