cssi/SciSciGPT-SciSciNet huggingface dataset:
High-velocity, high-excitation neutral carbon in a cloud in the Vela supernova remnant

HD 72089 is situated behind the Vela supernova remnant, and the interstellar absorption lines in the spectrum of this star are remarkable for two reasons. First, there are six distinct velocity components that span the (heliocentric) velocity range -60 to +121 km/s in the lines of Na I and Ca II. Second, two of the components at high velocity, one at +85 km/s and another at +121.5 km/s, have densities that are large enough to produce observable lines from neutral carbon. The gas moving at +121.5 km/s has such a large pressure that the excited fine-structure levels of the ground electronic state of C I are collisionally populated nearly in proportion to their level degeneracies. This high-velocity gas exhibits unusually low column densities of Mg I and Na I, compared to that of C I. We propose that the +121.5 km/s component represents gas that has cooled and recombined in a zone that follows a shock driven into a cloud by the very recent passage of a supernova blast wave. A representative preshock density of n(sub H) approximately = 13/cc and velocity v(sub s) = 100 km/s is indicated by the strength of diffuse (O III) emission lines seen in directions very near HD 72089. The strong collisional population of excited C I and apparent absence of excited levels of O I give a most favorable fit to the conditions 1000 less than n(sub H) less than 2900/cc over a temperature range 300 less than T less than 1000 K. The fact that the compression is not substantially more than this indicates that the preshock gas may have had an embedded, transverse magnetic field with a strength B greater than or approximately = 1 micro-G. The large dynamical pressure of the supernova blast wave that would be needed to create the cloud shock that we describe implies that the energy of the supernova was 8 x 10(exp 51) ergs, if the Vela remnant is 500 pc away. We can bring this value much closer to typical supernova energies E less than or approximately = 10(exp 51) ergs if the distance to the remnant is revised downward by at least a factor of 2.
Isotopic evidence for the paleoenvironmental evolution of the Mesoproterozoic Helena Formation, Belt Supergroup, Montana, USA

High-resolution isotopic and geochemical data constrain long-debated marine vs. lacustrine depositional models for the Helena Formation, a carbonate unit within the Mesoproterozoic Belt Supergroup, Montana. Paired carbon and oxygen isotope and minor element analyses of microsamples from a diverse array of petrographic components effectively distinguish between primary and secondary isotopic signatures. δ13C values reflecting primary depositional conditions increase progressively from an average of −0.‰ near the base of the Helena Formation to an average of +1.4‰ near the top, over a stratigraphic thickness of 100–200 m. Because the base of this 1.6‰ shift coincides with a basin-wide facies change marked by the appearance of stromatolitic units and an increased occurrence of features indicative of evaporative conditions and subaerial exposure, the shift toward more positive δ13C values is interpreted to reflect an increase in biologic productivity coupled with increasingly evaporative conditions in the eastern part of the Belt basin. δ13C values from the lower part of the Helena Formation are similar to those from other marine carbonates of similar age and suggest that the Belt basin was marine during deposition of the Helena Formation. Taken as a whole, these relations suggest that Helena sediments were deposited in a shallow marine basin that was increasingly isolated from the open Mesoproterozoic ocean. Original δ13O values have been retained only in syndepositional and early diagenetic intergranular cements in oolitic grainstones that occur in the upper part of the Helena Formation. The most positive δ13O values derived from these cements (∼ −6.1‰ PDB) are up to 3‰ higher than previous estimates for the δ13O value of Mesoproterozoic marine calcite. However, because these phases are associated with facies deposited under restricted marine conditions, interpretation of δ13O values from these cements with regard to the composition of the open Mesoproterozoic ocean awaits study of additional coeval marine carbonate successions.
Beyond Computation and Correctness: Contributions of Open‐Ended Tasks in Examining U. S. and Chinese Students’Mathematical Performance

How do Chinese and American students compare on open-ended mathematics tasks? Do they employ similar solution strategies? What challenges in test development emerge in such studies?
A controlled comparison study of the efficacy of training medical students in evidence-based medicine literature searching skills.

AbstractPurposeMany educational programs seek to develop skills in evidence-based medicine (EBM). The authors examined the efficacy of teaching the EBM skill of efficiently searching the research literature. They compared students who received brief training in EBM searching skills with those who di
On the structural stability of trade equations: the case of Japan

Abstract This study examines the stability of Japanese trade equations over the period 1976–1993. It finds evidence of parameter nondashconstancy in equations for both total and bilateral US-Japan trade. In most of the equations, the instability can be traced to changes in specific parameter estimates in the mid-1980s. In these cases, failure to account for the parameter changes leads to an underestimation of actual trade flows that, in some instances, is significant. By implication, standard trade equations estimated from historical data may not be applicable to the analysis of Japanese trade in the late 1980s and beyond.
Photoluminescence of HgTe/CdTe superlattices under high hydrostatic pressures.

We have measured the photoluminescence (PL) of HgTe/CdTe superlattices under high hydrostatic pressures up to 30 kbar at liquid-nitrogen temperature. We observed several photoluminescence peaks with energies ranging from \ensuremath{\sim}130 to \ensuremath{\sim}700 meV. The most prominent peak at \ensuremath{\sim}130 meV, which has been attributed to the recombination across the superlattice band gap, moves higher in energy with a pressure coefficient of \ensuremath{\lesssim}1 meV/kbar. Other peaks, whose origins are not well established, have higher energies and their pressure coefficients are in the range of 0--2 meV/kbar. A calculation based on the envelope-function approximation gives a pressure coefficient of at least \ensuremath{\sim}6.5 meV/kbar for the superlattice band gap. This is far outside the error bars of the measured pressure dependence of the main peak, \ensuremath{\lesssim}1 meV/kbar. Varying the input parameters for the calculation, including the valence-band offset, changes the result of the calculation by less than 10%. Possible explanations for this disagreement, including a modification of the current model of HgTe/CdTe superlattice bands and a reinterpretation of the PL peaks, are examined.
Management of rectal injuries

Rectal injuries result from a variety of insults and cause a heterogeneous spectrum of injuries to patients. Historically, many of these injuries were devastating, with high morbidity and mortality. They often required an aggressive approach to treatment including fecal stream diversion, distal rectal washout, and presacral drainage. Contemporary surgical care and a better understanding of the management of these injuries have dramatically improved outcomes. Although aggressive management including diversion is still the gold standard for treatment of severe injuries, some civilian injuries may require less aggressive management, including nonoperative management. By examining most studies published on rectal injuries in the last 50 years, this comprehensive review examines the incidence, demographics, mechanisms, associated injuries, diagnostic methods, and treatment recommendations. Rectal injuries remain a complex and challenging problem for the surgeon, and a thorough understanding of this disease process as well as the treatment options available is necessary to ensure a safe and successful outcome for the patient.
Probing isomeric differences of phosphorylated carbohydrates through the use of ion/molecule reactions and FT-ICR MS

Through the use of ion/molecule reactions and tandem mass spectrometry, phosphate position is assigned in both phosphorylated monosaccharides and oligosaccharides. In previous work [1, 2] phosphate moieties of monosaccharides were stabilized under collisional activation, by first derivatizing the deprotonated monosaccharide with trimethyl borate through an ion/molecule reaction, and the phosphate position determined through marker ions generated in tandem mass spectra. In this work, the methodology is extended to larger phosphorylated oligomers employing chlorotrimethylsilane (TMSCl) as the ion/molecule reagent. Phosphorylated monosaccharides were first investigated to determine diagnostic ions for phosphate linkage in monomeric standards. It was observed that the diagnostic ions showed both linkage and some monosaccharide stereochemical information. Furthermore, it was observed that TMS addition stabilized the phosphate moiety under collisionally activated conditions. Upon identification of the diagnostic ions, the methodology was applied to lactose-1-phosphate. It was found that TMSCl, stabilized the phosphate moiety upon collisional activation, and furthermore, the phosphate linkage could be determined through tandem mass spectrometric analysis. As a further extrapolation to biologically relevant problems, the methodology was applied to a lipophosphoglycan analog from the protozoan parasite Leishmania. This sample contains bridging phosphates which were converted to terminal phosphates through collision induced dissociation. The sample was then analyzed in the same manner as lactose-1-phosphate, yielding phosphate linkage information and stereochemical information. This study showed that, using the developed methodology, phosphate linkage can be determined from both monosaccharides and larger oligosaccharides; furthermore it is applicable to samples in which the phosphates are either terminating or bridging.
A travel cost study to estimate recreational value for a bird refuge at Lake Manyas, Turkey.

This paper investigates the recreational economic value of bird watching in the Kuscenneti National Park (KNP) at Lake Manyas, one of the Ramsar sites of Turkey and an important endangered species habitat. The lake and KNP provide considerable benefits for the region, although they have faced many environmental conflicts due to diverse stakeholders' needs. An economic valuation for the benefits provided by the KNP is important data for stakeholders and local authorities. The travel cost method is used to estimate recreational demand for the KNP. The recreational value of the KNP is 103,320,074 USD annually. Results shed light on important policy issues and help to resolve conflicts among stakeholders. This calculated value is considerably higher than the annual investment and operation expenditures of the KNP. Sustainability of the important species around the lake could be achieved if the region's inhabitants are compensated by KNP visitors.
Observations on the infection of Aedes sierrensis by a tetrahymenine ciliate

Abstract Melanized spots on the cuticles of larvae of Aedes sierrensis were sites of invasion or of attempted invasion by an organism resembling a species of Tetrahymena. Externally the invasion sites were capped by hemispherical membranes or cysts vacated by the invading ciliate. First- and second-instar larvae appeared most susceptible. Several factors limited successful infection by the ciliate such as host activity, host age, and cuticle thickness.
The treatment of patients with esophageal strictures by local steroid injections

Abstract Ten children have been treated with intralesional injection of triamcinolone diacetate into esophageal strictures. Five have responded well, and one result remains undetermined at present. Four patients are considered failures—3 due to long strictures and one with failure to improve significantly after four injections. No systemic effect of this dose of steroid has been observed, and only one complication has resulted. The apparent good result in the short strictures warrants continued clinical trials of this form of treatment. The treatment of strictures longer than 1.5 cm. by intralesional steroid injection is not recommended.
In Vivo Monitoring of Osseointegration

The process of osseointegration is the firm anchoring of a surgical implant by the growth of bone around it without fibrous tissue formation at the interface. This process is critical for long-term implant success. The ability to monitor this process in vivo would allow for personalization of loading protocols to increase the rate of implant success overall by ensuring that implants are not over or under loaded during recovery. Accordingly, there is a strong need for an instrument that has the sensitivity to noninvasively measure osseointegration in vivo. One of the objectives of the present study was to assess the performance of an instrumented percussion probe for quantitatively monitoring the osseointegration process.© 2007 ASME
Urinary protein expression patterns in children with sleep-disordered breathing: preliminary findings.

Abstract Background Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing, with almost 15 million Americans affected and many more at risk. Current diagnostic approach to OSA requires polysomnography, which is laborious, onerous, and time-consuming. There is ample evidence that inflammatory responses to the perturbations associated with OSA trigger a variety of genes and signaling cascades that ultimately lead to end-organ injury and changes in kidney function and protein expression. The aim of this study was therefore to analyze proteins in human urine and assess whether differential expression of particular proteins is associated with the presence of OSA. Methods Eleven OSA and 11 control children between the ages of three and 14 (males=17; females=5) underwent overnight sleep studies followed by a first-morning urine sample. Proteomic analysis of urine samples yielded a unique map of proteins, of which, five spots were selected for further analysis due to their significant intensity differences between OSA and control groups. Results Mass spectrometry followed by peptide mass fingerprinting conclusively identified four of the five spots as gelsolin, perlecan (a heparan sulfate proteoglycan), albumin, and immunoglobulin ( P 67). Conclusions Overall, increased expression of gelsolin and perlecan in the urinary proteome of children with OSA suggests that the episodic hypoxia associated with OSA may lead to changes in protein permeability or alternatively to increased catabolism of these proteins and their excretion in urine.
Near-field supersonic flow predictions by an adaptive unstructured tetrahedral grid solver

Applicability of a three-dimensional solution adaptive unstructured tetrahedral Euler flow solver about generic models for near-field sonic boom pressure signature predictions is evaluated. Comparisons of computational and experimental data demonstrates the capability of the method for predicting inviscid solutions useful for high speed calculations about simple 3-D geometries. The approach has promising features and results indicate potential for application to more complex configurations. The mesh generation is based on the advancing front technique, and steady state solutions of the Euler equations are achieved by explicit time integration. Spatial discretization uses the Taylor-Galerkin approach; an alternate time integration, based on the Runge-Kutta method, is also included. The solution-adaptive grid procedure is based on either remeshing or mesh refinement techniques. An alternative geometry-adaptive grid procedure has also been incorporated.
Shank length for determining sex in chukars

Shank length measurement of greater than or equal to 60 mm for males and less than 60 mm for females was used to predict sexes in male and female chukar partridges (Alectoris chukar) at 8, 10, 12, 20, 32, and 64 weeks of age. Growth of the shank is nearly complete at 10 weeks of age, whereas growth of body tissue continues to about 20 weeks of age. The best prediction of sexes was made at 10 weeks of age with an accuracy of about 95%. At 10 weeks of age, the accuracy for predicting males was higher than for females (98.5% vs 93%). At 64 weeks of age, best accuracy of sexes was made using a shank measurement of greater than or equal 61 mm for males and less than 61 mm for females. This technique to differentiate between sexes requires only a single shank measurement taken at 10 weeks of age and provides the grower and avian biologist with a reliable way of separating sexes for purposes of marketing, restoration, or selection of breeders at early ages.
Applications of Michael's selection theorems to fixed point theory

Abstract Applying some of Ernest Michael's selection theorems, from recent fixed point theorems on u.s.c. multimaps, we deduce generalizations of the classical Bolzano theorem, several fixed point theorems on multimaps defined on almost convex sets, almost fixed point theorems, coincidence theorems, and collectively fixed point theorems. These results are related mainly to Michael maps, that is, l.s.c. multimaps having nonempty closed convex values.
Attitudes Toward Sexual Partner Concurrency: Development and Evaluation of a Brief, Self-Report Measure for Field Research

The purpose of this study was to develop a brief, reliable, and valid self-report measure of attitudes toward sexual partner concurrency. Focus groups, conducted with 59 participants, yielded 26 common attitudes. STD clinic patients (n = 370) reported their sexual risk history, and rated the 26 attitude statements. This sample was randomly divided into two subsamples, with some participants completing the items on two occasions (separated by 3 months) to evaluate test-retest reliability. Both exploratory and confirmatory factor analyses confirmed a one-factor model. The final scale consisted of 10 items, with higher scores reflecting more positive attitudes toward sexual partner concurrency. This scale is internally consistent (α = 0.92) and stable over time (3-month retest ICC = 0.82), with a factor structure that is equivalent for men and women. Evidence of validity was also obtained by confirming hypothesized correlations with sexual risk history. Continued research is needed to confirm the usefulness of this measure as an antecedent of sexual risk behavior.
The Use of Botulinum Toxins for Chronic Pain and Headaches

The use of botulinum toxin in the management of various neurologic and non-neurologic disorders has grown considerably over the past decade. At the same time, new information regarding the mechanism of action of these toxins has evolved allowing for a greater understanding of the versatility of these agents. Although two types of botulinum toxin (type A Botox [Allergan, Inc., Irvine, CA] and type B Myobloc [Elan Products, New York) are commercially available in the US, most studies of the use of these toxins for the management of chronic pain and headache have been completed with type A. Data from open-label and retrospective studies as well as clinical practice suggest as strongly as possible that there is a role for these agents, especially Botox, in the management of several chronic headache disorders, including chronic migraine, chronic tension-type, cervicogenic, and cluster headache. Emerging data regarding the use of these agents for so-called “analgesic-rebound” headache also appear impressive; however, as of yet, no multicenter, randomized, controlled studies for any headache type have been published that confirm the results seen in noncontrolled studies. Nevertheless, the benefit that some patients experience from this agent is impressive, and this drug appears for many to modify the disorder in a very positive manner. In a similar fashion, data for other pain states are often restricted to open-label and case study approaches; however, clinical experience and some of the available studies (even small controlled studies) suggest a role for the toxins in the management of various chronic pain states, such as myofascial pain, low back pain, and neuropathic pain. One of the greatest challenges ahead for all interested in this area is confirming the benefit seen clinically through appropriately designed multicenter, randomized, controlled studies.
Determinants of shear stress-stimulated endothelial nitric oxide production assessed in real-time by 4,5-diaminofluorescein fluorescence.

The extremely short biological half-life of endothelial-derived nitric oxide (NO) has impeded real-time measurements of NO synthesis. We used the membrane-permeable fluorescent probe 4,5-diaminofluorescein diacetate (DAF-2 DA) to study determinants of NO synthesis in bovine aortic endothelial cells (BAECs). A step increase in shear stress (SS) from 0.3 to 3.4 dyne/cm2 triggered an increase in DAF-2 fluorescence starting 3.0 ± 0.5 min after the flow rise and peaking at 44.7 ± 7.2 min. This was abolished by intracellular Ca2+ chelation, but was unaffected by blocking extracellular Ca2+ influx or by inhibiting SS-related changes in intracellular pH. The increase in DAF-2 fluorescence occurred significantly earlier in BAECs transfected with either superoxide dismutase (SOD) or catalase (CAT), indicating concomitant reactive oxygen species (ROS) generation by SS and “competition” between ROS– and DAF-2–NO interactions. These data provide novel insights into several NO signaling determinants and reveal that DAF-2 can assess real-time SS-stimulated NO synthesis in endothelial cells. This should facilitate the analysis of NO-signaling pathways.
Snowy plover nest survival in Kansas and effective management to counter negative effects of precipitation

Snowy plovers (Charadrius nivosus) are a species of conservation concern throughout North America and listed as a threatened species in Kansas. Management to minimize the effects of flooding and predation were implemented at Kansas breeding sites in the 1980s to encourage reproductive success. However, the effectiveness of those strategies and the effect of other variables that may influence nest survival have not been formally assessed. We used Program MARK to model the daily survival rate (DSR) of 317 snowy plover nests with 14 habitat- and management-related covariates to identify factors that influence nest survival and examine the efficacy of current management practices. In 2005 and 2006, we monitored nests and collected habitat data at the 2 known breeding sites in Kansas, Quivira National Wildlife Refuge (NWR) and Cheyenne Bottoms Wildlife Area (WA). Overall DSR was greater at Quivira NWR in 2006 (0.954) than at Cheyenne Bottoms WA (0.917) and Quivira NWR (0.942) in 2005. We developed 88 candidate models of which 4 competing models (ΔAICc < 2) were identified. We selected the most parsimonious model (K = 14, wi = 0.23) as the remaining 3 included covariates deemed biologically uninformative. This model included the effect of study site and year on a quadratic time trend, and included covariates quantifying nest age; precipitation; the proportion of gravel, rock, and vegetation at nests; occurrence within an electric fence and within 20 m of a road; occurrence on a human-constructed nest mound; and adult capture during incubation. We found a strong positive relationship between the use of nest mounds and DSR, and a strong negative relationship between precipitation and DSR. We also found a strong positive relationship between DSR and the proportion of vegetation at nest sites, the occurrence of a nest within an electric fence, and adult capture at a nest. We noted a strong negative relationship between DSR and occurrence within 20 m of a road. However, we found that DSR was not sensitive to the proportion of vegetation at a nest, occurrence within an electric fence or within 20 m of a road, and to adult capture at a nest in light of covariates quantifying precipitation and the use of nest mounds. We found weak support for a positive relationship between DSR, nest age, and the proportion of gravel and rock at nests. Our results indicate that large rainfall events are a major source of snowy plover nest loss in Kansas that can be mitigated by the construction of nest mounds. Limited influence of environmental variables found to influence nest survival at other breeding sites suggests that threats to snowy plover nest survival are site specific and managers should assess local sources of nest loss prior to implementing management strategies to improve reproductive success. © 2012 The Wildlife Society.
Knee motion variability in patients with knee osteoarthritis: The effect of self-reported instability

Background Knee osteoarthritis has been previously associated with a stereotypical knee-stiffening gait pattern and reduced knee joint motion variability due to increased antagonist muscle co-contractions and smaller utilized arc of motion during gait. However, episodic self-reported instability may be a sign of excessive motion variability for a large subgroup of patients with knee osteoarthritis. The objective of this work was to evaluate the differences in knee joint motion variability during gait in patients with knee osteoarthritis with and without self-reported instability compared to a control group of older adults with asymptomatic knees.
Combating Noise and Other Channel Distortions in Chaotic Communications

A novel scheme is proposed for chaotic communications which is robust to noise and amplitude fluctuations in the channel. The scheme implements spread spectrum communication of binary data utilizing synchronized discrete-time chaotic systems. The chaotic signals of the transmitter are used as spreading codes, while the synchronized chaotic outputs of the receiver despread the signal, thereby recovering the message. The improved synchronization algorithm and the implementation of spread spectrum communications techniques result in reliable performance in the presence of considerable signal distortions in the channel. The method is implemented with a chaotic logistic map and also with a piecewise-linear map of a chaotic neuron. In both cases, average bit-error-rates were computed for varied signal-to-noise ratio, using additive white Gaussian noise. The proposed scheme also offers high privacy because of the non-periodicity of the chaotic spreading sequences.
Effects of oxygen, insulin, and glucagon concentrations on rat submandibular acini in serum-free primary culture

The objective of these studies was to develop serum-free culture conditions for dissociated acini from rat submandibular glands. Acini were isolated from the submandibular glands of 42–46 d old rats and cultured on reconstituted rat tail collagen containing laminin in 1:1 Ham’s F12 and Dulbecco’s media, supplemented with BSA, transferrin, insulin, T3, EGF, dexamethasone, retinoic acid, carbamylcholine, and trace elements, and gassed with 50% O2. The acini became partly embedded in the collagen gel and rapidly enlarged throughout the first 22 d of culture, maintaining modest seromucous acinar differentiation, as judged morphologically and by mucin secretion. Parallel cultures then were grown under 20, 35, 50, and 65% O2, and evaluated morphologically and by DNA content. Growth and retention of seromucous acinar characteristics were best with 35% O2, but lipid accumulation and cell death were unacceptably high. A spectrum of concentrations of insulin and glucagon then were tried. With 0.05µg/ml insulin, cellular growth and organization were orderly, lipid accumulations were not excessive, and moderate differentiation was retained through 15 d of culture. With more than 0.1µg/ml insulin added to or subtracted from the optimum, the detrimental effects recurred. Addition of sufficient glucagon counteracted the effects of both optimum and excessive concentrations of insulin. We now have achieved an orderly growth of moderately differentiated rat submandibular acini for 15 d in serum-free primary culture.
Deuterium isotope effects on the zero-field splittings of the lowest triplet state of benzaldehyde derivatives

Abstract The zero-field splitting parameters, D and E , in the lowest triplet state of p -chlorobenzaldehyde, p -methylbenzaldehyde, and their d 1 isotopes (aldehyde proton), are determined by ODMR measurements. The results show that the sign of the isotopic change in D reflects the orbital character of the lowest triplet state. The magnitude of D increases in the d 1 isotope of both guests in p -dimethoxybenzene where the lowest guest triplet state is 3 nπ*, but it decreases in p -xylene where the stae is 3 ππ*. The results are interpreted in terms of the spin—orbit interactions between the nearby 3 nπ* and 3 ππ* states and the isotopic changes in the zero-point energies of the states.
Dioxins, furans and dioxin-like PCBs in human blood: causes or consequences of diabetic nephropathy?

Abstract Nephropathy, or kidney disease, is a major, potential complication of diabetes. We assessed the association of 6 chlorinated dibenzo-p-dioxins, 9 chlorinated dibenzofurans and 8 polychlorinated biphenyls (PCBs) in blood with diabetic nephropathy in the 1999–2004 National Health and Nutrition Examination Survey (unweighted N=2588, population estimate=117,658,357). Diabetes was defined as diagnosed or undiagnosed (glycohemoglobin≥6.5%) and nephropathy defined as urinary albumin to creatinine ratio >30 mg/g, representing microalbuminuria or macroalbuminuria. For the 8 chemicals analyzed separately, values above the 75th percentile were considered elevated, whereas for the other 15 compounds values above the maximum limit of detection were considered elevated. Seven of 8 dioxins and dioxin-like compounds, analyzed separately, were found to be associated with diabetic nephropathy. The chemicals associated with diabetic nephropathy were: 1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin; 1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin; 2,3,4,7,8-Pentachlorodibenzofuran; PCB 126; PCB 169; PCB 118; and PCB 156. Three of the 8 dioxins and dioxin-like compounds; 1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin; 2,3,4,7,8-Pentachlorodibenzofuran and PCB 118; expressed as log-transformed continuous variables; were associated with diabetes without nephropathy. When 4 or more of the 23 chemicals were elevated the odds ratios were 7.00 (95% CI=1.80–27.20) for diabetic nephropathy and 2.13 (95% CI=0.95–4.78) for diabetes without nephropathy. Log-transformed toxic equivalency (TEQ) was associated with both diabetic nephropathy, and diabetes without nephropathy, the odds ratios were 2.35 (95% CI=1.57–3.52) for diabetic nephropathy, and 1.44 (95% CI=1.11–1.87) for diabetes without nephropathy. As the kidneys function to remove waste products from the blood, diabetic nephropathy could be either the cause or the consequence (or both) of exposure to dioxins, furans and dioxin-like PCBs.
Interspecies comparisons of particle deposition and mucociliary clearance in tracheobronchial airways

Inhaled insoluble particles that deposit along normal healthy tracheobronchial airways of humans and other mammals are transported on the proximally moving mucous lining to the larynx, where they are swallowed. The transit time from the most distal ciliated airways varies from 0.1 to 1 d, with each individual having a relatively constant, characteristic time. The exact time course of clearance depends on the distributions of both particle deposition and mucus velocities along the airways. There are too few data on intrabronchial deposition and mucociliary transport rates for laboratory animals to permit a thorough intercomparison among species. However, enough is known about the relative lung sizes and anatomical differences among the various species to make some preliminary, but important, distinctions. As compared to commonly used experimental animals, humans have larger lungs and a more symmetric upper bronchial airway branching pattern. In addition, humans do considerable oral breathing, thus bypassing the effective air cleaning capability of the nasal airways. These differences contribute to a greater amount of upper bronchial airway particle deposition in humans, as well as to greater concentrations of deposition on localized surfaces near airway bifurcations. Airborne irritants that deposit in small ciliated airways may produce marked changes in mucociliary transport. Such materials include cigarette smoke, submicrometer-sized sulfuric acid mist, nitrogen dioxide, and ozone. For cigarette smoke and sulfuric acid, which have been studied for transient effects following single brief exposures in both humans and animals, the responses are similar. Upon repetitive exposures in animals, both of these irritants produce persistant alterations in clearance rates and airway morphometry. Studies of the effects of ozone on mucociliary clearance have, up to now, been limited to tests of the responses of rats to single exposures. The similarities between the known effects of various irritants suggests a nonspecific response.
Transposition of a tandem duplication of yeast mating-type genes.

The switching of mating-type genes in both homothallic and heterothallic strains of the yeast Saccharomyces cerevisiae involves a site-specific transposition event1–3. A sequence at the mating-type locus (MAT) is replaced by a copy of a or α information from the unexpressed, loci, HML or HMR. Although MATa and MATα contain unique sequences of ∼700 base pairs (bp), they are flanked by sequences that are also found at HML and HMR4,5 (Fig. 1a). Recent results6–8 have suggested that the switching of MAT alleles involves an intrachromosomal mitotic gene conversion event, in which a donor sequence at HML or HMR pairs with the homologous sequences at the MAT locus. On this view the switching of mating-type information must be able to accommodate the region of non-homology in a heteroduplex structure. (Analogous gene conversions of non-homologous regions have been well documented during meiosis at MAT and for deletions in other yeast genes9,10.) One prediction of a gene conversion mechanism is that it should be possible to transpose a tandem duplication of mating-type genes from HMR to MAT. In such a switch, pairing would occur between MAT and homologous sequences flanking the two copies of the tandem duplication at HMR. Our results reported here demonstrate that a tandem duplication created at HMR by recombinant DNA techniques can be transposed to MAT without the loss of these sequences at the donor locus.
Carbon-supported Fe-Ru catalysts prepared from stoichiometric mixed-metal carbonyl clusters

Highly dispersed Fe-Ru crystallites were obtained on an amorphous carbon black using mixed-metal carbonyl precursors. These catalysts were characterized by chemisorption of CO and H/sub 2/ at 195 and 300 K and their kinetic properties in the CO hydrogenation reaction were determined. If not exposed to air, only a low-temperature pretreatment at 473 K was required to reduce essentially all the Fe in the Fe/sub 3/(CO)/sub 12/ catalyst to activate it. In contrast, air exposure did not affect the reduction behavior of the Ru-containing catalysts. Both chemisorption and kinetic behavior indicated that surface enrichment in Fe occurred in these small crystallites after reduction, which is consistent with studies of bulk Fe-Ru systems. Turnover/frequencies (TOF) for CH/sub 4/ and total hydrocarbon formation increased in parellel with the increase in surface Ru concentration whereas the TOF for CO/sub 2/ smoothly decreased. Distinct differences in catalytic behavior were observed for a coimpregnated Fe/sub 3/(CO)/sub 12/ plus Ru/sub 3/(CO)/sub 12/ catalyst, compared to the mixed-metal cluster catalysts, indicating a lack of homogeneity when using this procedure. Scanning transmission electron microscope micrographs showed a raft-like structure for the metal crystallites in the small-pore structure of carbon, and this morphology may be partially responsible for themore » differences in catalytic behavior and the activity stability which exists between these carbon-supported metals and the same metals on other supports. 45 refs., 3 figs., 9 tabs.« less
Compression wraps for venous ulcer healing: a review.

Abstract Compression to the lower extremities is used to increase healing of venous stasis ulcers by improving the blood supply and reducing edema and distension. Compression wraps are available in elastic or nonelastic and in single to multilayer systems requiring varying types of application and exerting different levels of compression. Elimination of edema is so basic and important to venous ulcer healing that the most effective level of compression should be used. Controversy exists regarding the most effective subbandage pressure (ranging from 20 mm Hg to 45 mm Hg) for timely healing. Because of differences in compression wraps, selection of the most effective and efficient wrap can be difficult. The purpose of this integrated review was to determine healing rates of venous ulcers with various wraps. The studies reviewed provide reasonable evidence that venous ulcers can be healed with the use of compression wraps and that various wraps are effective when used with correct assessment, application, and fit by the caregiver, along with compliance and mobility of the patient.
Interaction between pathogenic fungi in culture. Considerations on the mechanism of cell division in the dimorphism of pathogenic fungi.

A mutual antagonism (in vitro) has been shown betweenTrichophyton rubrum andCandida albicans by means of two membered pure cultures and by means of cultures filtrates from each organism grown singly. The growth ofT. rubrum was inhibited by metabolic products ofC. albicans. The pigment ofT. rubrum has been shown to be a pH indicator in vivo. Metabolic products ofT. rubrum completely inhibit the development of mycelia byC. albicans, but have little effect on growth in the yeast phase. Chemical fractionation experiments indicated that there are two diffusible metabolic products ofT. rubrum affecting mycelia development: 1) soluble in water and in acetone, heat stable, and adsorbed by activated charcoal, 2) soluble in water, insoluble in acetone, heat labile, and not adsorbed by activated charcoal. The general phenomenon of yeast to mycelia conversions has been considered in detail. A notation system has been developed in this connection; yeast (Y) to mycelia (M) transformations may be expressed as Y→M; interconversions of the type exhibited byBlastomyces may be written Y:⇉M. The relationships between these processes and the analogous bacteria (B) to filament (F) conversions, B→ F, has been pointed out. Evidence that Y.→.M, Y⇄M, and B→F may result from the inhibition of a common unit enzymatic mechanism has been presented. Converging evidence from such diverse fields as the physicochemical study of the kinetics of bacterial growth (Hinshelwood), genetics of irradiated bacteria (Witkin; Eisenstark andClark), cytochemical mechanism of penicillin action (Pratt andDufrenoy), and dimorphism of pathogenic fungi (this paper;Nickerson andEdwards) are all interpreted as pointing in this direction.
Single-molecule magnets: a large Mn30 molecular nanomagnet exhibiting quantum tunneling of magnetization.

The largest single-molecule magnet (SMM) to date has been prepared and studied. Recrystallization of known [Mn12O12(O2CCH2But)16(H2O)4] (1; 8MnIII, 4MnIV) from CH2Cl2/MeNO2 causes its conversion to [Mn30O24(OH)8(O2CCH2But)32(H2O)2(MeNO2)4] (2; 3MnII, 26MnIII, MnIV). The structure of 2 consists of a central, near-linear [Mn4O6] backbone, to either side of which are attached two [Mn13O9(OH)4] units. Peripheral ligation around the resulting [Mn30O24(OH)8] core is by 32 ButCH2CO2-, 2 H2O, and 4 MeNO2 groups. The molecule has crystallographically imposed C2 symmetry. Variable-temperature and -field magnetization (M) data were collected in the 1.8−4.0 K and 0.1−0.4 T ranges and fit by matrix diagonalization assuming only the ground state is occupied at these temperatures. The fit parameters were S = 5, D = −0.51 cm-1 = −0.73 K, and g = 2.00, where D is the axial zero-field splitting parameter. AC susceptibility measurements in the 1.8−7.0 K range in a zero DC field and a 3.5 G AC field oscillating at frequencie...
Philadelphia chromosome-negative chronic myelogenous leukemia with rearrangement of the breakpoint cluster region. Long-term follow-up results.

Background. Five to 10% of patients with chronic myelogenous leukemia (CML) do not have the Philadelphia chromosome (Ph), but one-third of them have rearrangements of the breakpoint cluster region (BCR-positive). Methods. The authors analyzed the characteristics, treatment response, and prognosis of 23 patients with BCR-positive, Ph-negative CML, and compared them with patients with Ph-positive CML, Ph-negative BCR-negative CML and chronic myelomonocytic leukemia (CMML) treated during the same period. Results. Seventeen patients had early chronic phase CML, 3 had late chronic phase, 2 had accelerated phase, and 1 had blastic phase. The median age was 44 years (range, 14-71 years), median platelet count was 402 × 109/l, and median leukocyte count was 86 × 109/l. Fourteen of the 17 patients with early chronic phase CML received alpha-interferon; 12 (86%) achieved complete hematologic remission. Median survival in chronic phase CML was 60 months (range, 3-90+ months). Patients with Ph-negative BCR-positive CML and those with Ph-positive CML had similar characteristics and outcome. Compared with patients with Ph-negative BCR-negative CML and CMML, patients with Ph-negative BCR-positive CML and Ph-positive CML were significantly younger, had a significantly higher incidence of leukocytosis, thrombocytosis, and peripheral and marrow basophilia, and a significantly lower incidence of anemia, thrombocytopenia, marrow blast percent, and peripheral and marrow monocytosis. The median survival was 60 months for Ph-negative BCR-positive CML, 73 months for Ph-positive CML, 25 months for Ph-negative BCR-negative CML, and 9 months for CMML (P < 0.001). When analyzed adjusting for their stage, patients classified with Ph-negative BCR-positive CML Stage I disease had a significantly better survival than did patients with Ph-negative BCR-negative CML (P < 0.02). Conclusions. Patients with Ph-negative BCR-positive CML are similar to those with Ph-positive CML and should be treated with the same approaches. Cancer 1995;75:464-70.
Cryptography versus cryptanalysis in wireless sensor networks

Maintaining a cryptanalysis free environment determines the success of a sensor network. Nevertheless, the ability to maintain a cryptanalysis free environment is the ultimate goal of a wireless sensor network. In the paper, the focus is to show the importance maintaining an efficient cryptographic wireless sensor network versus a cryptanalysis wireless sensor network.
Poisson mixture yield models for integrated circuits : A critical review

Yield models for semiconductor devices are often derived from Poisson mixtures, the specific model being dependent on the distribution assumed for the density of point defects. Presented here is a review of the development of such yield models, including two new models obtained by using the Rayleigh and the inverse Gaussian as mixing distributions. The various models are compared and some general properties of yield functions for any Poisson mixture are derived. The concept of reference region is introduced and its implication for yield modeling is discussed.
Iodine Tris(trifluoroacetate)

[14353-86-7] C6F9IO6 (MW 465.96) InChI = 1S/C6F9IO6/c7-4(8,9)1(17)20-16(21-2(18)5(10,11)12)22-3(19)6(13,14)15 InChIKey = LLKSJVKRWAPXNE-UHFFFAOYSA-N (formation of trifluoroacetoxy-substituted alkanes,5, 6 reacts with alkenes to form bis(trifluoroacetates);10 iodinates arenes;7, 8 preparation of iodonium salts via [bis(trifluoroacetoxy)iodo]arenes;9 induces 1,2-migration in arylalkenes;11 formation of α,β-trifluoroacetoxy diesters from cyclic ethers5, 12, 13) Alternate Names: ITT; tris(trifluoroacetoxy)iodane. Physical Data: mp 120 °C (dec). Solubility: sol CH2Cl2, CHCl3. Form Supplied in: yellow crystals; not commercially available. Analysis of Reagent Purity: elemental analysis.4 Preparative Method: Trifluoroacetic Acid oxidation of Iodine;2 reaction of Silver(I) Trifluoroacetate with ICl3;3 reduction of IO2(CO2CF3) with I2;2 or action of Nitric Acid/Trifluoroacetic Anhydride on I2.4 Purification: sublimation (90 °C/10−3 mmHg).4 Handling, Storage, and Precautions: stable compound; store in the absence of moisture in a sealed container under nitrogen, protected from light. Handle in a fume hood.
The Delegation Lottery

Replying to Matthew C. Stephenson, Legislative Allocation of Delegated Power: Uncertainty, Risk and the Choice Between Agencies and Courts, 119 Harv. L. Rev. 1035 (2006). Matthew Stephenson models "the decision calculus faced by a rational, risk-averse legislator who must choose between delegation to an agency and delegation to a court." On the assumption that delegation to agencies tends to produce interpretive consistency across issues while delegation to courts tends to produce interpretive consistency over time, a risk-averse legislator interested in reducing variance along either dimension will face a tradeoff between intertemporal risk diversification and interissue risk diversification. From this basic tradeoff, Stephenson derives comparative statics about the rational, risk-averse legislator's choice of delegates under various conditions. I suggest that Stephenson's legislative-delegation model rests on excessively artificial assumptions and is unable to yield significant predictions - in either the political or statistical sense. In particular, it is unsatisfying to model legislators as entering a "policy lottery" by enacting ambiguous delegating statutes, but then also to picture them as clearly specifying the identity of the delegate. The same institutional and political factors that tend to produce a first-order policy lottery over statutory substance also tend to produce a second-order "delegation lottery" over the question whether agencies or courts have ultimate interpretive authority. Moreover, the factors the model includes are, at best, second-decimal considerations relative to the factors it excludes.
Tubular linear induction motor for hydraulic capsule pipeline. II. Finite element method (FEM) maximum thrust design

For part I see ibid., vol. 8, no.2, pp. 251-256 (1993). The axisymmetric analysis of the magnetic field and the finite element method (FEM) formulation of the tubular linear induction motor (TLIM) for application to hydraulic capsule pipelines was discussed in part I. In these studies a three-phase sinusoidal current source supplies the stationary windings to produce a traveling magnetic field inducing currents in the cylindrical capsule conducting wall to produce thrust on the capsule. The results of the different studies using the developed FEM tool show that by introducing iron elements in the pipe wall, the thrust can be increased. Five cases are discussed here, and the magnetic field contours for each case are presented. FEM computation of the thrust for all cases is compared to choose the design which produces the maximum thrust. >
Epstein-Barr Virus Binding to CD21 Activates the Initial Viral Promoter via NF-κB Induction

Epstein-Barr virus (EBV), an oncogenic human herpesvirus, binds to and infects normal human B lymphocytes via CD21, the CR2 complement receptor. Studies of the mechanisms that enable EBV to infect nonactivated, noncycling B cells provide compelling evidence for a sequence of events in which EBV binding to CD21 on purified resting human B cells rapidly activates the NF-κB transcription factor, which, in turn, binds to and mediates transcriptional activation of Wp, the initial viral latent gene promoter. Thus, EBV binding to its cellular receptor on resting B cells triggers an NF-κB–dependent intracellular signaling pathway which is required for infection.