cssi/SciSciGPT-SciSciNet huggingface dataset:
MEMBRANE-BOUND RIBOSOMES IN KIDNEY: Methods of Estimation and Effect of Compensatory Renal Growth

Membrane-bound ribosomes are thought to secrete protein for export and free ribosomes to secrete protein for intracellular use. The proportion of the total ribosomes that is bound to membranes in normal mouse kidneys has been estimated by three different methods, and the results have been compared with those obtained by a fourth method used by us previously. The most valid estimates appear to be those obtained ( a ) by comparison of radioactivity in peaks representing free and membrane-bound ribosomes on linear sucrose gradients after labeling for 24 hr with 14 C-orotic acid, and ( b ) by measurements of optical density in free and bound ribosomes that had been separated by centrifugation on discontinuous gradients of 0.5 M/2.0 M sucrose. Analyses by these methods show that about 20–25% of the ribosomes in a postnuclear supernatant prepared from mouse kidneys, but only 10–15% of the ribosomes in a post-mitochondrial supernatant, are membrane-bound. About 75% of the bound ribosomes sediment as polysomes of many different sizes. The proportion of membrane-bound ribosomes and their aggregation into polysomes were unchanged in kidneys undergoing compensatory hypertrophy after removal of the opposite kidney. These experiments show that, unlike liver, kidney has a predominance of free ribosomes compared to bound ribosomes; those ribosomes that are membrane-bound do not become free during compensatory renal growth.
Homocysteine-dependent demethylation of trimethylselenonium ion and selenobetaine with methionine formation.

Abstract In the presence of rat liver cytosol and homocysteine, trimethylselenonium ion (TMSe + ) underwent time-dependent demethylation to dimethylselenide with the concurrent formation of methionine. Convenient methods were developed for assay of this activity using either radioactive methods based on the gamma emitting isotope 75 Se or nonradioactive HPLC assay of methionine. The rate of demethylation was linear with protein concentration and dependent on homocysteine, which could not be replaced by cysteine, glutathione, or dithiothreitol. The TMSe + demethylation rate was inhibited by the addition of betaine, sulfobetaine (dimethylthetin), or dimethylglycine. The K m for TMSe + was 8 mM compared to 0.04 mM for betaine, but the rate of TMSe + demethylation was approximately 50-fold that of betaine when both were assayed at 25 mM. Methionine was also produced from selenobetaine, selenobetaine methylester, and sulfobetaine. The selenium analogues of betaine inhibited the demethylation of TMSe + with only minor decreases in methionine production, indicating substrate competition. In preliminary studies aimed at the partial purification of the TMSe + :homocysteine methyltransferase activity, the enzyme was found to have chromatographic and heat stability characteristics similar to betaine:homocysteine methyltransferase. The data indicate that betaine:homocysteine methyltransferase, or a very similar enzyme, is involved in the demethylation of TMSe + and show that TMSe, an in vivo urinary selenium metabolite of many selenium compounds, is not biologically inert.
Economic aspects of scientific journalism in the seventeenth and eighteenth centuries

The proliferation of scientific journals, starting in the middle of the seventeenth century, marked the beginnings of a new epoch in the dissemination of scientific information. The new medium brought with it the influences of a long heritage going back to scribal cultures, which even before the invention of printing, had produced almanacs and newsletters in writing. The economics of periodical publications varied little from those associated with other kinds of printing in this period. They involved the relationship of fixed and variable costs and their effect on edition size in relationship to anticipated markets. Examples of these aspects of scientific publishing are examined in scientific journals published independently and under the auspices of scientific societies in the seventeenth and eighteenth centuries.
Effects of group treatment for women with a history of childhood sexual abuse.

Objective: Empirical support for the effectiveness of group therapies for women with a history of childhood sexual abuse is scant. This study examined the feasibility of conducting abuse-focused research and group treatment on a short-term unit and evaluated the effectiveness of the Women’s Safety in Recovery group. Methods: Eighty-six women with a history of childhood sexual abuse participated in treatment as usual (N=38) or in the Women’s Safety in Recovery group (N=48). The latter group met three times weekly for one hour, focusing on patients’ current safety and self-care. Participants completed the Symptom Checklist—Revise d at baseline, discharge, and six-month follow-up. Patients rated their experience in treatment at discharge and sixmonth follow-up, and therapists rated patients’ treatment experiences at discharge. The feasibility of the treatment group was measured by enrollment rates, group attendance, and attrition. Results: Eighty-two percent of eligible patients agreed to enroll in the study. Women’s Safety in Recovery participants attended an average of ten group meetings. Seventy percent of enrollees completed discharge assessments, and of these, 82 percent completed the six-month follow-up. Compared with treatment-as-usual patients, Women’s Safety in Recovery participants reported greater symptom improvement and reported that their childhood sexual abuse issues had been more thoroughly addressed. These differences were present at discharge and at six-month follow-up. Therapists also perceived that abuse issues of these participants had been more thoroughly addressed. Conclusions: Women’s Safety in Recovery participants reported significant reductions in distress compared with those receiving treatment as usual. The abuse-focused research program and the Women’s Safety in Recovery group proved feasible, despite attrition. (Psychiatric Services 50:686–692, 1999)
Visualization of aortic valve leaflets using black blood MRI.

Although magnetic resonance imaging (MRI) is capable of imaging various physiological parameters associated with the heart valves, it has generally been difficult to visualize the valve leaflets directly. The aortic valve was imaged in 120 patients referred for cardiac MRI to assess myocardial volumes or mass. The average patient age was 37 and ranged from 9 to 75 years. Heart rate ranged from 43 to 100 bpm. Imaging was performed on a 1.5 T scanner equipped with enhanced gradients and a cardiac phased-array coil. A double inversion recovery fast spin-echo sequence was used to acquire short-axis images of the aortic valve in a breath-hold (15 +/- 3 seconds). All three leaflets of the aortic valve were seen in 102 of 120 studies (85%). Two leaflets were detected in another 15 subjects. No leaflets were seen in three individuals. Seven cases of a bicuspid or thickened aortic valves were clearly distinguished from normal valves. The signal-to-noise ratio of aortic leaflets (14 +/- 5) was significantly higher than that of the residual blood signal in the aortic root (7 +/- 4, P < 0.001). MR images showed the aortic valve leaflets in a high fraction of people with suspected normal aortic valves and detected seven cases of abnormal aortic valves. The potential of MRI to study both the anatomic and functional consequences of valvular heart disease warrants further study. J. Magn. Reson. Imaging 1999;10:771-777.
Radiative Transfer in Pulsed-Laser-lnduced Plasma

When a high-power pulsed laser interacts with materials, a plasma layer containing micrometer-size particles is formed above the target surface. The laser induced plasma changes the energy coupling mechanism between the laser beam and the target. This work investigates the radiative heat transfer process in the excimer laser generated plasma layer on the Ni specimen, in the laser fluence range between 1.5 and 5 J/cm2 . Novel diagnostic techniques are developed to measure transient transmission and scattering of the thin plasma layer within the duration of the laser pulse. Based on the measurement results, radiative heat transfer analysis is performed to evaluate the radiative properties of the plasma layer, including the optical depth, the absorption coefficient, the single scattering phase function, and the scattering size parameters. Knowledge of the radiative properties of the laser induced plasma helps to understand the energy transfer process during laser-materials interaction. Further, this work demonstrates the feasibility of using the transient scattering measurement for in situ monitoring of the size of the laser ejected particles.
Swirl effects on harmonically excited, premixed flame kinematics

Abstract This paper describes the response of a swirling premixed flame with constant burning velocity to non-axisymmetric harmonic excitation. This work extends prior studies of axisymmetric forcing, which have shown that wrinkles are excited on the flame that propagate downstream along the mean flame surface at a speed given by U o cos ψ , where U o is the mean flow velocity and ψ is the flame angle. The swirl component in the flow field introduces an azimuthal transport mechanism for disturbances on the flame. As such, the flame response at any given position is a superposition of flame wrinkles excited at earlier times, upstream axial locations, and different azimuthal positions. These swirl transport effects do not arise in problems where axisymmetric flames are subjected to axisymmetric excitation, but enter quite prominently in the presence of non-axisymmetries, such as when the flame is subjected to transverse excitation. The solution characteristics are strongly dependent upon the ratio of angular rotation rate to excitation frequency, denoted by σ = Ω / ω , which describes the fraction of azimuthal rotation a disturbance makes in one acoustic period. When σ ≪ 1 and σ ≫ 1, the axial wavelength of flame wrinkles scales with the convective wavelength, λ c , but becomes much longer for σ ∼ O (1). The spatial variation in phase of flame wrinkling is also strongly dependent upon σ . Regardless of swirl number, flame wrinkles propagate in helical spirals along the solution characteristics at a phase speed equal to the local tangential velocity. The axial phase characteristics of flame wrinkling at a fixed azimuthal location, as would be measured by laser sheet imaging, are much more complex. For σ σ , however, and becomes zero at σ = 1 for a compact flame. For σ > 1, the wrinkles actually have a positive roll-off character for the phase with axial downstream distance, indicating a flame wrinkle with a negative trace velocity, but whose actual propagation velocity is positive. Finally, these results show that while the flame response to transverse acoustic excitation is quite strong locally, its spatially integrated effect is much smaller for acoustically compact flames. This suggests that the dominant mechanism through which the flame responds globally to transverse excitation is the induced vortical and longitudinal acoustic fluctuations.
ON THE ITERATED PRISONER'S DILEMMA IN A FINITE POPULATION

Two standard assumptions in analytical work on the iterated prisoner's dilemma are that the population is infinite, and that opponents—though randomly selected—are fixed for the duration of the game. This paper explores the consequences of relaxing both assumptions. It is shown in particular that if opponents are drawn at random throughout the game, then stable cooperation via reciprocity requires both that the probability of a further interaction be sufficiently high—higher than when opponents are fixed—and that the population not exceed a certain critical size, which depends on the probability of further interaction.
Fast and long term optical sensors for pH based on sol–gels

Abstract Long lasting and fast response optical sensor for the detection of pH in the range of 6–12 is described. The sensor is fabricated by spin coating silica sol in the presence of phenol red (PR). The sol is in turn obtained by acidic hydrolysis of tetraethoxysilane (TEOS) and phenyltriethoxysilane (Ph-TriEOS). The performance of the sensor depends on the ratio of Ph-TriOES to TEOS. At the optimal composition, the sensor has a response time of less than 20 s, the response is completely reversible and its life-time is over 12 months.
Absolute intensity calibrations of solar K line profiles

Individual K-line profiles from elements of fine structure on the surface of the Sun are calibrated absolutely. The continuum calibrations of Labs and Neckel and of Houtgast and Namba are considered, and the average K-profile is scaled to that of White and Suemoto.
Loading for parallel binary channels

We develop optimal probability loading for parallel binary channels, subject to a constraint on the total probability of sending ones. The distinctions from the waterfilling power loading for parallel Gaussian channels, particularly the latter's "dropping" of poor-quality channels, are highlighted. The only binary-input binary-output channel that is never dropped is the Z-channel.
A First-Passage Kinetic Monte Carlo algorithm for complex diffusion-reaction systems

We develop an asynchronous event-driven First-Passage Kinetic Monte Carlo (FPKMC) algorithm for continuous time and space systems involving multiple diffusing and reacting species of spherical particles in two and three dimensions. The FPKMC algorithm presented here is based on the method introduced in Oppelstrup et al. [10] and is implemented in a robust and flexible framework. Unlike standard KMC algorithms such as the n-fold algorithm, FPKMC is most efficient at low densities where it replaces the many small hops needed for reactants to find each other with large first-passage hops sampled from exact time-dependent Green's functions, without sacrificing accuracy. We describe in detail the key components of the algorithm, including the event-loop and the sampling of first-passage probability distributions, and demonstrate the accuracy of the new method. We apply the FPKMC algorithm to the challenging problem of simulation of long-term irradiation of metals, relevant to the performance and aging of nuclear materials in current and future nuclear power plants. The problem of radiation damage spans many decades of time-scales, from picosecond spikes caused by primary cascades, to years of slow damage annealing and microstructure evolution. Our implementation of the FPKMC algorithm has been able to simulate the irradiation of a metal sample for durations that are orders of magnitude longer than any previous simulations using the standard Object KMC or more recent asynchronous algorithms.
Project management in relocating a plant from a large Northern city to a small Southern town

Abstract This is a case study of the problems faced by a medium-sized company in relocating a manufacturing plant from a highly industrialized Northern city to a Southern town in the late 1970s. The various avenues the company used to identify and attempt to solve its problems are explored. The project discussed in this paper was not a project undertaken by Dupont. The author was hired as a project engineer by Typical Manufacturing Corporation ∗ . This employment provided internship experience for a M.S. degree. The author has seen how a small company handles a major relocation project, and how it handled its personnel problems.
Controlled release from and tissue response to physically bonded hydrogel nanoparticle assembly

Our recent work on synthesis and application of thermally gelling nanoparticle dispersions is briefly reviewed here. These nanoparticles consist of interpenetrating polymer networks (IPN) of poly-acrylic acid (PAAc) and poly(N-isopropylacrylamide) (PNIPAM). The aqueous IPN nanoparticle dispersions with polymer concentrations above 2.5 wt % underwent an inverse thermoreversible gelation at about 33 °C. Dextran markers of various molecular weights as model macromolecular pseudodrugs were mixed with the IPN nanoparticle dispersion at room temperature. At body temperature, the dispersion became a gel. The dextran release profiles were then measured using UV-visible spectroscopy. The biocompatibility of this nanoparticle assembly was assessed using an animal implantation model.
The role of heme and iron-sulfur clusters in mitochondrial biogenesis, maintenance, and decay with age

Mitochondria decay with age from oxidative damage and loss of protective mechanisms. Resistance, repair, and replacement mechanisms are essential for mitochondrial preservation and maintenance. Iron plays an essential role in the maintenance of mitochondria, through its two major functional forms: heme and iron-sulfur clusters. Both iron-based cofactors are formed and utilized in the mitochondria and then distributed throughout the cell. This is an important function of mitochondria that is not directly related to the production of ATP. Heme and iron-sulfur clusters are important for the normal assembly and for the optimal activity of the electron transfer complexes. Loss of mitochondrial cytochrome c oxidase (complex IV), integrity of mtDNA, and function can result from abnormal homeostasis of iron. We review the physiological role of iron-sulfur clusters and heme in the integrity of the mitochondria and the generation of oxidants.
Prostate Cancer Region Prediction using MALDI Mass Spectra

For the early detection of prostate cancer, the analysis of the Prostate-specific antigen (PSA) in serum is currently the most popular approach. However, previous studies show that 15% of men have prostate cancer even their PSA concentrations are low. MALDI Mass Spectrometry (MS) proves to be a better technology to discover molecular tools for early cancer detection. The molecular tools or peptides are termed as biomarkers. Using MALDI MS data from prostate tissue samples, prostate cancer biomarkers can be identified by searching for molecular or molecular combination that can differentiate cancer tissue regions from normal ones. Cancer tissue regions are usually identified by pathologists after examining H&E stained histological microscopy images. Unfortunately, histopathological examination is currently done on an adjacent slice because the H&E staining process will change tissue's protein structure and it will derogate MALDI analysis if the same tissue is used, while the MALDI imaging process will destroy the tissue slice so that it is no longer available for histopathological exam. For this reason, only the most confident cancer region resulting from the histopathological examination on an adjacent slice will be used to guide the biomarker identification. It is obvious that a better cancer boundary delimitation on the MALDI imaging slice would be beneficial. In this paper, we proposed methods to predict the true cancer boundary, using the MALDI MS data, from the most confident cancer region given by pathologists on an adjacent slice.
POLYNOMIAL VARIATIONS ON A THEME OF SIERPIŃSKI

In 1960, Sierpinski proved that there exist infinitely many odd positive integers k such that k · 2n + 1 is composite for all integers n ≥ 0. Variations of this problem, using polynomials with integer coefficients, and considering reducibility over the rationals, have been investigated by several authors. In particular, if S is the set of all positive integers d for which there exists a polynomial f(x) ∈ ℤ[x], with f(1) ≠ -d, such that f(x)xn + d is reducible over the rationals for all integers n ≥ 0, then what are the elements of S? Interest in this problem stems partially from the fact that if S contains an odd integer, then a question of Erdos and Selfridge concerning the existence of an odd covering of the integers would be resolved. Filaseta has shown that S contains all positive integers d ≡ 0 (mod 4), and until now, nothing else was known about the elements of S. In this paper, we show that S contains infinitely many positive integers d ≡ 6 (mod 12). We also consider the corresponding problem over &#x1d53d;p, and in that situation, we show 1 ∈ S for all primes p.
Surgical management of the axilla: do intramammary nodes matter?

Abstract Background The therapeutic significance of intramammary lymph nodes is uncertain. The purpose of this study was to identify the appropriate surgical management of the axilla in intramammary node–positive patients undergoing sentinel lymph node (SLN) biopsy. Methods A retrospective review of consecutive patients staged between September 1996 and December 2004 was performed. Intramammary node identification and pathologic findings were compared with the status of axilla. Results Among 7,140 patients, intramammary nodes were identified in 151 (2%). Positive intramammary nodes were identified in 36 patients (24%). Axillary disease was identified in 61% of intramammary node–positive patients. No additional axillary disease was identified when axillary lymph node dissection was performed in intramammary node–positive patients with negative axillary SLN biopsy results. Conclusions The results suggest that completion axillary lymph node dissection may be based on the status of axillary SLN biopsies in clinically node negative patients when intramammary lymph node metastases are identified in the breast specimens.
Shear and Pressure Driven Flow and Thermal Transport in Microchannels

In many practical circumstances, the flow in microchannels is driven by moving surfaces that impart shear to the fluid. The shear may generate a pressure differential or the pressure may be imposed to affect the resulting flow and heat transfer. Processes where such flows arise include coating, cooling and thermal treatment of moving wires, fibers, and microscale devices. One particularly important circumstance is the optical fiber coating process, where both the entrance of the moving surface into a reservoir of fluid, as well as the exit, are of interest, since the thermal transport in the relevant microchannels influences the resulting coating very substantially. Similarly, the drawing of microscale fibers and the cooling of fibers after drawing are important in the overall manufacturing process and involve microchannel transport. This paper discusses the basic considerations in such processes, particularly the flow that arises in drawing and coating and the menisci that are observed at the inlet and outlet regions of the two microchannels. Experimental and analytical/numerical work has been carried out on these flows and the results obtained are presented. An important aspect is the pressure rise in the channel for narrowing flow domains, such as those employed in dies, and a comparison with imposed pressures. It is found that, in many practical problems, the shear generates much higher pressures than the typically imposed pressures and, thus, the flow is largely dominated by the shear effects due to the moving surfaces. It is also found that the flow develops very rapidly in forced convective cooling by gases, such as nitrogen and helium, resulting in thermal transport in a largely developed flow region. Comparisons between experimental and numerical results show fairly good agreement, indicating the validity of the model for such complex microchannel flows.Copyright © 2008 by ASME
Saturn's sweeper moons predicted

The recent observation of the absorption of radiation belts in the vicinity of Saturn's bright rings and historical observations of the ring system make the following related results apparent: - The gaps in the rings are caused by the presence of at least 6 small, extremely dense and probably electrically charged ‘sweeper’ moons which effectively sweep the ring matter clean from the gaps. This is known due to the fading of the inner ring edges whereas the outer edges are well defined. Their orbital periods will differ from the expected Keplerian periods if the moons and Saturn do possess electric fields. - Absorption of radiation belts near the rings (of Jupiter also) implies that the ring particles themselves are not absorbing the radiation but the small moons are. This is consistent with the observed radiation belt absorption near the outer Saturnian moons. - If electric fields of the sweeper moons cause the ring edge fading as observed (and not simply gravitational), then Saturn itself must maintain an electric field in its vicinity by way of a sizeable proton wind to affect the uneven ring edge fading and will be surrounded by an H+ cloud at least to approximately the A-ring. this is consistent with the detection of an H+ cloud surrounding Saturn (Weiseret al., 1977, p. 755). The other possibility is that these moons are extremely dense and have very large internal magnetic fields. - Because of their location, these moons must be captured and if very dense as believed, may be core remnants of a nova.
Rodent BDNF genes, novel promoters, novel splice variants, and regulation by cocaine.

Abstract Results from studies using molecular and genetic methods in humans and rodents suggest that brain-derived neurotrophic factor (BDNF) is involved in the behavioral effects of abused drugs, making understanding of its genomic structure and regulation of substantial interest. Recently, we have reported that the human BDNF gene contains seven upstream exons that can each be spliced independently to the major BDNF coding exon to form diverse bipartite BDNF transcripts. We also identified a novel “BDNFOS” gene that is transcribed to produce alternatively spliced natural antisense transcripts (NATs); its fifth exon overlaps with the protein coding exon VIII of human BDNF. To better understand BDNF's genomic structure and differential regulation, we now describe the rodent BDNF gene and transcripts. This gene includes six bipartite transcripts that are generated by six independently transcribed exons, each of which is spliced to a major coding exon and a tripartite transcript that is composed of two upstream exons and one coding exon. In addition, we found no evidence for antisense, opposite strand BDNFOS gene transcripts in mice or rats. The BDNF rodent splice variants display specific patterns of differential expression in different brain regions and peripheral tissues. Acute cocaine administration increased striatal expression of a specific BDNF4 splice variant by up to 5-fold. Interestingly, however, neither experimenter- nor self-administered chronic cocaine administration enhanced striatal BDNF expression. These data suggest a role of specific BDNF promoter regions and regulatory sequences in stimulant-induced alterations in BDNF expression, and in the alterations that changed BDNF expression is likely to confer in the brain.
The use of touch preparation for the evaluation of sentinel lymph nodes in breast cancer

BACKGROUND: This study was undertaken to evaluate the accuracy of touch preparation (touch prep) in the evaluation of sentinel lymph nodes (SLNs). METHODS: We performed a retrospective review of 402 breast cancer patients who underwent SLN biopsy. RESULTS: A SLN was identified in 381 patients. Of 61 patients with a true positive result, 59 underwent axillary node dissection, and in 22 the SLN was the only node with metastases. Thirty-six (9.44%) had at least 1 false negative result. Twenty-five with a false negative results were due to macrometastases, with 17 (2.4%) false negatives occurring in patients with invasive ductal and 6 (5.5%) in those with invasive lobular histology, P = .04. Touch prep had an overall sensitivity of 62.89% and specificity of 98.94%. CONCLUSIONS: Touch prep for the evaluation of SLNs in breast cancer compares favorably to reported results for frozen section. False negative findings are more likely with micrometastases and invasive lobular histology.
A pulse radiolysis study of the reactions of 3-hydroxykynurenine and kynurenine with oxidizing and reducing radicals

Abstract Pulse radiolysis has been used to study the reactions of 3-hydroxykynurenine and kynurenine with solvated electrons, superoxide radicals, hydroxyl radicals and azide radicals. Both 3-hydroxykynurenine and kynurenine react with solvated electrons with diffusion controlled rate constants ( k = 2.5 · 10 10 M −1 s −1 and 2.3 · 10 10 M −1 s −1 , respectively). Neither compound was observed to react with superoxide radicals under our experimental conditions, an upper limit of 1.2 · 10 5 M −1 s −1 for the rate constant of this reaction was estimated for both compounds. However, we do observe that a stable product of autooxidation of 3-hydroxykynurenine reacts with superoxide radicals and we calculate a lower limit for the rate of this reaction of 5.8 · 10 6 M −1 s −1 . Reactions of 3-hydroxykynurenine and kynurenine with hydroxyl radicals proceed with diffusion controlled rate constants (1.2 · 10 10 M −1 s −1 and 1.3 · 10 10 M −1 s −1 , respectively). The measured values for the rate constants for reaction of 3-hydroxykynurenine and kynurenine with azide radicals are 2.1 · 10 10 M −1 s −1 and 4.8 · 19 9 M −1 s −1 , respectively. The differences in these rate constants are attributed to differences in the measured oxidation potentials for 3-hydroxykynurenine (+ 1.0 V vs. NHE) and kynurenine (+ 1.15 V vs. NHE).
Vision-based intelligent control for automated assembly

Development of an automated assembly system requires integration of different engineering modules and coordination of interactions between these modules. This paper presents some of the results of an effort in developing an assembly automation schene for an automated work cell. Integration of the control scheme with the vision module and an on-line trajectory planner is presented. Special characteristics of this automation scheme are dynamic integration of vision and feedback control, real-time operation, uncertainty compensation and error recovery. The hardware required for implementation of this scheme is described. Results of implementing this scheme on a PUMA robot performing a carburetor and gasket mating operation are presented.
Predictors of regaining ambulatory ability during hospitalization

BACKGROUND Loss of ambulatory ability with acute hospitalization is common and often does not improve by discharge. OBJECTIVES To define admission predictors of regaining ambulatory ability during hospitalization in patients with expected activity limitations. DESIGN Prospective cohort study. SETTING University teaching hospital. PARTICIPANTS Two hundred and eighty-six patients at least 55 years of age whose activity was expected to be limited to a bed or chair for at least the first 5 days of hospitalization or who had a hip fracture, who were ambulatory in the 4 weeks prior to hospital admission, and whose length of stay in the hospital was less than 32 days. MEASUREMENTS Baseline data collected from admission physician and nurse interviews and abstracted from the medical records included length of stay, demographic characteristics, global health measures, presence of specific diseases, and hospital-related factors hypothesized to affect ambulation. Nurses were asked weekly if patient activity was still expected to be limited to a bed or chair. RESULTS Despite initially being limited to a bed or chair, 42% had regained ambulatory ability by discharge. Recovery of ambulatory ability was independently associated with not being married (odds ratio [OR] = 3.0, 95% confidence interval [CI] 1.4-6.2), higher physician-rated life expectancy (OR = 1.9, 95% CI 1.3-2.8), absence of restraints (OR = 2.5, 95% CI 1.2-5.5), having a urinary catheter (OR = 2.2, 95% CI 1.2-5.5), having deep vein thrombosis (OR = 11.4, 95% CI 1.2-105.1), and having a higher level of bed mobility at admission (OR = 1.7, 95% CI 1.1-2.6). CONCLUSIONS Recovery of ambulatory ability is closely associated with physician-rated life expectancy and hospital-related factors, particularly those that affect mobility. Early recognition of who will recover ambulatory ability may help with discharge planning and potential interventions. Journal of Hospital Medicine 2006;1:277–284. © 2006 Society of Hospital Medicine.
Approximating a harmonizable isotropic random field

The class of harmonizable fields is a natural extension of the class of stationary fields. This paper considers a stochastic series approximation of a harmonizable isotropic random field. This approximation is useful for numerical simulation of such a field.
Global thermospheric neutral density and wind response to the severe 2003 geomagnetic storms from CHAMP accelerometer data

[1] Measurements of atmospheric density near 410 km from the STAR accelerometer on the CHAMP satellite are used to illustrate the spatial-temporal dependence of the thermospheric response to the severe solar storms occurring during 29 October to 1 November 2003. This interval includes periods of elevated magnetic activity with KP values of 5–9, as well as undisturbed intervals that serve to define quiet time baseline densities. Measurements are available from −87° to +87° latitude during both day and night at local times near 1300 and 0100 hours, respectively. During times of maximum geomagnetic activity for this study, density measurements exhibit enhancements of 200–300%. Northern Hemisphere daytime responses are much larger than in the Southern Hemisphere; the origins of this effect are unknown. Nighttime density disturbances more readily propagate to equatorial latitudes, possibly facilitated by the predominant equatorward flow in both hemispheres due to the diurnal tides driven by in situ EUV heating. The CHAMP density measurements are compared with density predictions from the NRL-MSISe00 empirical density model and demonstrate some model shortcomings. Measurements of cross-track accelerations provide the opportunity to estimate zonal winds from the equator to about ±60° latitude, transitioning to a measure of purely meridional winds at the turning point of the orbit near ±87° latitude. A periodic variation in cross-track winds with an apparent period of 24 hours appears at high latitudes and exhibits similar amplitudes and temporal-latitudinal structures to the empirical HWM-93 wind model when projected into the cross-track direction. This periodicity is due to the displacement of geomagnetic and geographic coordinates. At low latitudes, CHAMP and HWM-93 both yield westward winds of order 100 ms−1 during midday under quiet magnetic conditions; however, during severely disturbed periods the HWM-93 winds generally show a greater westward intensification (to 250 ms−1) than the CHAMP measurements. At night, CHAMP winds are near zero under quiet conditions whereas HWM-93 indicates eastward winds of order 50–100 ms−1. Under disturbed conditions the CHAMP winds shift to westward values of order 200 to 250 ms−1, while HMW-93 values do not exceed about 50 ms−1 in the westward direction. The physical origins of the observed effects are difficult to isolate, and unequivocal interpretation will require sophisticated numerical modeling taking into account self-consistent interactions between the neutral winds, drifts, and ionization densities.
Training in virtual and real environments

Transfer of training between real and virtual environments was examined using a pick-and place task with two different difficulty levels. The task was to minimize the time to move cans from one color coded location in the first row to the same color coded location in the back row and then to reverse the process. In the first task, the front and back disk colors were aligned, and in the second disk order, the front and back disk colors were randomly placed on the table. Subjects trained in one environment were then tested in the other and their performance compared with that of subjects being trained in that environment. Some virtual world-trained subjects showed small but significant improvement in performance compared with the untrained subjects for the real world task for both disk arrangements. The differences in performance between the two groups decreased with trial number until no difference was seen at the end of the sessions. None of the real world-trained subjects showed any significant improvement when performing the task in the virtual world compared with the untrained subjects. These results suggest that transfer-of-training from virtual to real world tasks can take place under certain conditions.
What are Residents Learning at Night? A Qualitative and Quantitative Assessment of Resident Self-Identified Learning Themes

BACKGROUND: Nighttime rotations bring a unique challenge for providing the teaching that was previously available during daytime conferences and rounds. In order to improve nighttime education, many educators havewondered what residents actually learn at night and how to best capture these learning experiences, especially in the context of the new work hours. METHODS: During a 6 month period, pediatric residents on nighttime rotations at Lucile PackardChildren sHospital at Stanfordwere given a survey requesting 4 self-identified learning topics and 4 triggers which prompted the associated learning points. 58 surveys were completed (response rate of 91%). 267 learning topics and 238 learning triggers were identified. Qualitative analysis was conducted by three authors and responses were categorized by theme. Chi-square analysis compared themes based on resident level. RESULTS: 1) Learning theme categories differed significantly between R1s, R2s, and R3s (p 1⁄4 .03). Medical knowledge was the most frequent learning theme for all three levels. R1s identified learning points on practice-based learning and improvement (R1 8%, R2 4%, R3 2%) and systems-based practice (R1 15%, R2 2%, R3 11%) more often than R2s and R3s. R2s identified clinical decision-making learning points more frequently (R1 19%, R2 32%, R3 18%). R3s identified learning points on supervising more often (R1 2%, R2 0%, R3 9%). 2) Learning triggers also differed significantly betweenR1s,R2s, andR3s (p1⁄4.002). Specific patient encounterwas themost frequent learning trigger for all three levels. R1s identified formal teaching as a learning trigger more frequently than R2s and R3s. (R1 21%, R2 0%, R3 5%). CONCLUSIONS: What residents learn at night and what triggers their learning differ significantly by resident level. Understanding these learning points and triggers can help guide educators in better creating nighttime curricula and tailoring teaching to the level of learner.
Wage Structure and Dynamics in the Electronics Industry

This study analyzes wage patterns over time among California electronics employers. While the range of wages paid is substantial, employers on average make only small departures from market wage that are not pervasive across occupations or persistent across time. Employers appear able to change employment levels without affecting wages. Internal wage relativities also appear flexible. Differences between administered wage scales and actual wages paid are used to distinguish wage policy from market outcomes.
Another look at the rate of increase in TFP in China

There has been some controversy concerning the rate of growth of total factor productivity after economic reform started in China in 1978. It is the purpose of this note to present evidence to show that an annual rate of increase of about 2.7% is reliable and that the capital elasticity of output is close to 0.6. I first present time series evidence and then supporting evidence from other sources.
Electrocatalysis with a Dirhodium-Substituted Polyoxometalate Anchored in a Xerogel-Based Composite: Application to the Oxidation of Methionine and Cystine at Physiological pH

Replacing a tungsten oxide group of phosphotungstic acid with a Rh(II) acetate dimer yielded a species, Rh2POM, that catalyzed the electrochemical oxidation of L-methionine (L-Met), L-cystine, and As(III). The electrocatalytic activity of Rh2POM was greater than that of the simple Rh(II) acetate dimer in homogeneous solution. A conducting carbon-composite electrode (CCE) comprising Rh2POM and carbon powder in a silica matrix prepared by sol-gel chemistry was catalytically active over the pH range 2–10. The CCEs produced voltammetric responses toward L-Met and L-cystine that were pH independent over the above range and were stable for at least 4 months under dry storage. If passivated, the catalytic activity was reproducibly generated by polishing. For example, a relative standard deviation of 2.9 % (5 points) was obtained when the surface was polished between cyclic voltammetric experiments on 5.0 mM L-Met at pH 7.4. A least squares fit of flow injection amperometric data obtained over the range 5–156 μM L-Met (7 points) yielded the following: slope, 0.85 μA mM−1; intercept, 0.05 μA; and r / 0.995. The detection limit was 2.3 μM.
Monetization of Bridewealth and the Abandonment of 'Kin Roads' to Marriage in Sana, Mali

Through an analysis of the marriage process in the Bambara communities of Sana Province in Mali, marriage and its associated prestations are shown to constitute a social universe that not only reflects but also helps to reorder social reality. Eschewing the jural approach in favor of one that contextualizes social phenomena such as bridewealth, the article demonstrates that changes in the creation of marriage alliances and the composition of prestations relate to transformations in the very dynamics of the social system.
On the role of complementation in implicit language equations and relations

We solve systems of boolean implicit equations and relations with union and complementation. If the languages are regular, we determine whether a system of implicit boolean equations or relations has solutions. If there is a solution, we provide an effective construction of a (regular) solution. We give representations for maximal and minimal solutions. Moreover, we also solve the problem of uniqueness of solutions as well as whether infinitely many solutions exist.
Suppression of streptococcal cell wall–induced arthritis by human chorionic gonadotropin

Objective To determine whether human chorionic gonadotropin (HCG) contributes to pregnancy-associated immunosuppression, as observed clinically by an amelioration of symptoms in human autoimmune diseases, including rheumatoid arthritis, during pregnancy. Methods Administration of HCG was initiated 2 days prior to an arthritogenic dose of streptococcal cell wall (SCW) in nonpregnant female rats, and the development and severity of SCW-induced arthritis was monitored. Inflammatory mediators, including plasma nitrite/nitrate and cytokine levels, were measured. Inducible nitric oxide synthase (iNOS) protein and cytokine messenger RNA expression in joint tissue were compared between treated and untreated arthritic animals. Results Systemic administration of HCG resulted in a dose-dependent reduction in the clinical arthritis index. Consistent with the amelioration of clinical symptoms, HCG significantly reduced the inflammatory cell infiltration, pannus formation, and bone and cartilage degradation. Mechanistically, HCG therapy was associated with suppression of the overzealous production of tumor necrosis factor α, interleukin-6 (IL-6), and IL-1β, which contribute to synovial pathology in animals with SCW-induced arthritis. Circulating nitric oxide and the amount of iNOS protein were also reduced. Furthermore, circulating transforming growth factor β levels were elevated by the HCG, all of which suggest monocytes/macrophages as a potential target. Conclusion These findings indicate that HCG exerts a protective effect in this experimental arthritis model, through modulation of inflammatory mediators.
Effect of physical activity on bone mass

Maintenance of bone mass depends on several factors, including proper level of physical activity, hormones, and nutrition. Prescribing effective weight-training and weight-bearing exercise programs for improving bone mass is highly desirable. Specificity of each exercise program can contribute to an increment or reduction of bone mass. Cessation of physical activity induces rapid metabolic bone changes, although the effects on bone mass take time to develop. Therefore, weight-bearing and periodic high-intensity loading exercises are recommended for maintenance of bone mass in the spine and lower extremities. Patients who endure a period of immobility such as prolonged bed rest should resume their daily activities in addition to supervised exertional exercises. While research continues in an effort to find ways to increase bone mass despite aging and negative genetic factors, more focus can be given to building a solid skeletal foundation through good nutritional and exercise habits developed early in life.
Does Gender Affect Mortgage Choice? Evidence from the US

This study examines the effect of gender on the choice of adjustable- versus fixed-rate mortgages among mortgage applicants in the United States. While adjustable-rate mortgages (ARMs) are initially cheaper, they expose the borrower to interest rate risk. Using linear probability models applied to US lender data for 2004–6, the study finds that the propensity to apply for an ARM among higher-income applicants is lower for women by 3.7–8.4 percentage points or 12–42 percent. Results are robust to the inclusion of education, financial knowledge, and economic determinants of mortgage choice. Results are consistent with past findings of women being more risk averse than men in financial behaviors. Findings of this US-based study are relevant for other countries, as ARMs of varying lengths are widely prevalent outside the US.
Magnetoacoustic Tomography With Magnetic Induction: Bioimepedance Reconstruction Through Vector Source Imaging

Magnetoacoustic tomography with magnetic induction (MAT-MI) is a technique proposed to reconstruct the conductivity distribution in biological tissue at ultrasound imaging resolution. A magnetic pulse is used to generate eddy currents in the object, which in the presence of a static magnetic field induces Lorentz force based acoustic waves in the medium. This time resolved acoustic waves are collected with ultrasound transducers and, in the present work, these are used to reconstruct the current source which gives rise to the MAT-MI acoustic signal using vector imaging point spread functions. The reconstructed source is then used to estimate the conductivity distribution of the object. Computer simulations and phantom experiments are performed to demonstrate conductivity reconstruction through vector source imaging in a circular scanning geometry with a limited bandwidth finite size piston transducer. The results demonstrate that the MAT-MI approach is capable of conductivity reconstruction in a physical setting.
A comparison of suggestibility in 4-year-old girls in response to parental or stranger misinformation.

This study examined the effect of the child's relationship with the interviewer on the quality and quantify of information obtained when interviewers have no knowledge of the event. Eighty-one 4-year-old girls were randomly assigned to one of four conditions in which they individually viewed a videotaped interaction of two children. Subsequently, children were interviewed by either their parent or a “parent stranger” using either a standardized set of misleading or nonmisleading questions. Results revealed that children in the misleading condition were more suggestible when misinformation was introduced by a stranger than by their parents. However, in the nonmisleading condition, children reported a greater amount of both accurate and inaccurate information to their parents than to strangers. Differences in children's accuracy are explained in terms of children's familiarity and trust with interviewers and perceptions of interviewer credibility. Implications for professionals interviewing children are discussed.