cssi/SciSciGPT-SciSciNet huggingface dataset:
Subtle Conformational Changes Induced in Major Histocompatibility Complex Class II Molecules by Binding Peptides

Intracellular trafficking of major histocompatibility complex (MHC) class II molecules is characterized by passage through specialized endocytic compartment(s) where antigenic peptides replace invariant chain fragments in the presence of the DM protein. These changes are accompanied by structural transitions of the MHC molecules that can be visualized by formation of compact SDS-resistant dimers, by changes in binding of mAbs, and by changes in T cell responses. We have observed that a mAb (25-9-17) that is capable of staining I-Ab on the surface of normal B cells failed to interact with I-Ab complexes with a peptide derived from the Eα chain of the I-E molecule but bound a similar covalent complex of I-Ab with the class II binding fragment (class II-associated invariant chain peptides) of the invariant chain. Moreover, 25-9-17 blocked activation of several I-Ab-reactive T cell hybridomas but failed to block others, suggesting that numerous I-Ab-peptide complexes acquire the 25-9-17+ or 25-9-17− conformation. Alloreactive T cells were also able to discriminate peptide-dependent variants of MHC class II molecules. Thus, peptides impose subtle structural transitions upon MHC class II molecules that affect T cell recognition and may thus be critical for T cell selection and autiommunity.
Natural perchlorate has a unique oxygen isotope signature.

Perchlorate is known to be a minor component of the hyperarid Atacama Desert salts, and its origin has long been a subject of speculation. Here we report the first measurement of the triple-oxygen isotope ratios (18O/16O and 17O/16O) for both man-made perchlorate from commercial sources and natural perchlorate extracted from Atacama soils. We found that the δ18O values (i.e., normalized 18O/16O ratios) of man-made perchlorate were at −18.4 ± 1.2‰, whereas natural perchlorate has a variable δ18O value, ranging from −4.5‰ to −24.8‰. The δ18O and δ17O values followed the bulk Earth's oxygen isotope fractionation line for man-made perchlorate, but all Atacama perchlorates deviated from this line, with a distinctly large and positive 17O anomaly ranging from +4.2‰ to +9.6‰. These findings provide a tool for the identification and forensics of perchlorate contamination in the environment. Additionally, they confirm an early speculation that the oxidation of volatile chlorine by O3 and the formation of HClO4 can...
Examination of the folding of E. coli CspA through tryptophan substitutions

Escherichia coli cold shock protein, CspA, folds very rapidly (time constant, τ = 4 msec) by an apparent two-state mechanism. However, recent time-resolved infrared (IR) temperature-jump experiments indicate that the folding trajectory of CspA may be more complicated. The sole tryptophan of wild-type CspA (Trp11), which is used to monitor the folding process by fluorescence spectroscopy, is located in an unusual aromatic cluster on the surface of CspA within the nucleic acid binding site. To gain a more global picture of the folding kinetics of CspA and to determine if there are any previously undetected intermediates, we have introduced a second tryptophan at three different surface locations in the protein. The three mutations did not significantly alter the tertiary structure of CspA, although two of the substitutions were found to be slightly stabilizing. Two-state folding, as detected by stopped-flow fluorescence spectroscopy, is preserved in all three mutants. These results indicate that the fast folding of CspA is driven by a concerted mechanism.
Prevalence of microfissures in the human temporal bone : a report of 1000 temporal bones

A total of 1000 human temporal bones were studied to determine the prevalence of two microfissures: 1. the one between the facial canal and the vestibule, 2. the microfissure between the round window niche (RWN) and the posterior semicircular canal (PSC). Additionally, this study compares the prevalence according to temporal bone age and sex The microfissure between the facial canal and the vestibule was observed in 470 (47%) temporal bones, with a bilateral presence of 77.2%. The prevalence of this microfissure increases linearly with age. It was not found in any bone within the 0 to 2 age group. It was present in 3 (7.3%) bones from the 2 to 9 age group, as opposed to 374 (54.8%) bones from the 40 and over group The microfissure between the RWN and the PSC was detected in 915 (91.5%) temporal bones. This second microfissure was found to be an overwhelmingly bilateral entity. The prevalence of this other microfissure also increases with age. This microfissure was also not present in any temporal bone within the 0 to 2 age group. It was found in 28 (68.3%) bones from the 2 to 9 age group, in contrast to 678 (99.4%) temporal bones from the 40 + group In addition to a review of the literature, the possible clinical significance of these microfissures is discussed.
Distribution of Tritiated Human Chorionic Gonadotropin in Superovulated Rat Ovary

SummaryTritium-labeled human chorionic gonadotropin was administered to superovulated rats. The ovary showed the highest uptake of the organs assayed. The uptake reached a maximal level during the second hr after the administration and declined thereafter. The uptake of [3H]HCG was inhibited when administered with native HCG, suggesting that HCG competed with [3H] HCG.Ovarian autoradiography showed that the silver grains were localized around the periphery of the luteal cells. The present results suggest that HCG probably acts on the cell membrane of the corpus luteum and only a minute amount, if any, enters the cell.
Monster Protein Controls Calcium Entry and Fights Infection

Sustained calcium signaling in T cells is critical for development and activation. In this issue of Immunity, Matza et al. (2007) demonstrate that the huge scaffold protein, AHNAK1, interacts with L-type calcium channels, regulates Ca2+ influx, and defends against Leishmania major infection.
Developmental and injury induced plasticity in the micturition reflex pathway

The storage and periodic elimination of urine are dependent upon neural circuits in the brain and spinal cord that co-ordinate the activity of the urinary bladder, the urethra and the striated urethral sphincter. This study utilized anatomical, electrophysiological and pharmacological techniques to examine: (1) the organization of the parasympathetic excitatory reflex mechanisms that control the urinary bladder of the rat and the cat; and (2) the changes in these reflexes during postnatal development and after spinal cord injury. In normal adult cats and rats, the parasympathetic excitatory input to the bladder is dependent upon a spinobulbospinal reflex pathway that is activated by myelinated (Aδ) bladder afferents and that passes through an integrative center (the pontine micturition center, PMC) in the rostral brain stem. Transneuronal tracing studies using pseudorabies virus as well as physiological methods have revealed that the PMC is located in close proximity to the locus coeruleus. Single unit recordings indicate that neurons in the PMC respond to afferent input from the bladder and are excited prior to or during reflex bladder contractions. Glutamic acid is the major excitatory transmitter in the micturition reflex pathway. Glutamatergic transmission which is mediated by AMPA/kainate and NMDA receptors can be modulated by a variety of other transmitters. In neonatal animals, a spinal micturition reflex is activated by somatic afferent fibers from the perigenital region. This reflex is suppressed during postnatal development, but can be unmasked in adult animals following spinal cord injury. Spinal injury also causes the emergence of a spinal bladder-to-bladder reflex which in the cat is activated by capsaicin-sensitive C-fiber bladder afferents. Patch clamp studies in spinal cord slice preparations indicate that developmental and spinal cord injury induced plasticity in sacral parasympathetic reflex pathways is due in part to alterations in glutamatergic excitatory transmission between interneurons and preganglionic neurons. Changes in the electrical properties of bladder afferent pathways may also contribute to the reorganization of bladder reflexes in paraplegic animals.
A Pattern Recognition Technique for System Error Analysis

The error analysis problem is the resolving of a limited set of measurements in terms of a large set of possible but improbable physical errors. The relation between the measurements and the errors is modeled in part as a set of linear undetermined equations ?v = A?r, where ?v is a vector of the measurements and ?r is a vector of error parameters, and in part by specification of the relations between the parameters ?ri and the physical errors. An approximate solution to the model equations is deemed physically reasonable if it reflects one or only a few of the physical errors. To evaluate a candidate solution consisting of ?r and its interpretation as physical errors, we introduce a criterion function ? = ?0 + ?1; ?0 is a measure of ??v - A?r? and ?1 is a measure of the likelihood of the composite physical error associated with ?r. With this criterion, the common least-squares (pseudoinverse) solution of the model equations is shown to be inadequate (it minimizes ?0 but not ?). A pattern recognition technique is presented and shown to yield solutions that are both numerically and physically reasonable, i.e., both ?0 and ?1 are small. The technique is illustrated by application to miscalibration analysis using an inertial guidance system model.
Race, Hegemonic Masculinity, and the ‘‘Linpossible!’’: An Analysis of Media Representations of Jeremy Lin

In February 2012, Jeremy Lin, the first American of Taiwanese and Chinese descent to play in the National Basketball Association (NBA), led the Knicks to seven straight victories while establishing an NBA scoring record. This study analyzes how U.S. mass media contextualized Lin’s meteoric rise in the NBA and explores assumptions grounded in the media coverage of Lin, including how race and masculinity are defined within a dominant ideological field and how notions of a hegemonic masculinity define the “other.” This article looks at mass media as a site of complicity for the construction and maintenance of hegemonic masculinity by examining media representations and sports media columnists’ coverage of Jeremy Lin’s meteoric rise in the NBA from February 5 to March 15, 2012. Critical discourse analysis reveals that the majority of mainstream news media outlets did not overtly racialize Lin’s meteoric rise to stardom. However, the research uncovered several instances of racialized coverage and the incorpora...
Decline in pre-school use in post-socialist societies: the case of Bulgaria:

Child care is often analysed in its role as facilitator of women's labour-force participation. However, for pre-school-aged children, child care can also contribute in important ways to human-capital development, especially among poor children. By international standards, pre-school enrolments were high under socialism. Since transition, however, enrolment rates have declined. This may leave large numbers of children without the preparation necessary to succeed in school and to be included in the region's post-socialist development. We examine the changing dynamics of preschool enrolment in Bulgaria. We evaluate demand and supply-side explanations for changing enrolments and use municipal-level data to develop a simple model of demand. We examine the impact of changing employment and earnings, proximity and perceived quality of child-care centres, as well as ethnic/cultural background. Through this model, we hope to broaden understanding of preschool enrolment decisions, and to assist policymakers in impr...
Heterogeneous Translational Dynamics of Rhodamine B in Polyelectrolyte Multilayer Thin Films Observed by Single Molecule Microscopy

The lateral diffusion dynamics of rhodamine B (RB) in polyelectrolyte multilayer (PEM) thin films has been studied with single-molecule confocal fluorescence microscopy. The films were made with sodium poly(sodium 4-styrenesulfonate) (PSS) and poly(diallydimethlyammonium chloride) (PDDA). Analysis of the real-time emission intensity traces reveals three diverse components of translational motion: (1) fast diffusion of RB through the confocal detection volume; (2) reversible tracer adsorption processes; and (3) nanoconfined diffusion. These processes cover a wide range of time scales. Analysis via fluorescence correlation spectroscopy (FCS) involves multicomponent fitting of the autocorrelated emission data. The model includes a free Brownian diffusion parameter, D, and two rate constants of desorption, k−1 and k−2. For RB in a PSS/PDDA thin film made with 0.01 M NaCl in the polyelectrolyte buildup solutions, D = 1.7 × 10−7 cm2/s, k−1 = 30 s−1, and k−2 = 0.1 s−1. FCS was also performed on RB/PEM samples ma...
THE COMPUTATION OF VISCOSITY AND RELAXATION TIME OF DOUGHS FROM BIAXIAL EXTENSION DATA

Stress (T) versus time (t) data were obtained for wheat flour doughs in lubricated, constant crosshead speed, uniaxial compression experiments. These data were then analyzed by using the Upper Convected Maxwell (UCM) Model with two parameters, a relaxation time (Λ) and a shear viscosity (η). The numerical solutions to the differential equation governing the behavior of the UCM model in this experiment can be very sensitive to the initial slope of the stress/time plots. This region of the curve, near t = 0, is most sensitive to experimental error. Best-fit values of Λ and η were thus computed for a given curve at a series of initial starting points, ti, which were sequentially taken up the stress/time plots. There was considerable fluctuation in the best-fit parameters but, nevertheless, values of relaxation time and shear viscosity could be obtained that gave good agreement between computed and experimental stress/strain curves.
Natural abundance 13C NMR spectra of human muscle, normal and diseased

13C NMR spectra of human surgical muscle samples have been obtained at 50 and 118 MHz. Numerous sharp peaks in the 13C spectrum have been assigned to carbon atoms of soluble metabolites and fatty acyl chains of neutral fats and membrane-bound phospholipids. Comparisons have been made of 13C NMR spectra of normal and diseased muscles after removal of neutral fat by extraction with isopentane. Creatine, lactic acid, and phospholipids are not removed from muscles by isopentane. The most striking difference between 13C NMR spectra of isopentane-extracted normal and diseased muscle samples was the size of the residual 30.5 ppm methylene carbon resonance, that is, small in normal muscles and in nonspecific muscle diseases, but large in myogenic and neurogenic muscle diseases. In addition, differences were also found between normal and diseased muscles in their creatine content and their ability to produce lactic acid. By deoxycholate treatment of isopentane-extracted diseased muscle it is estimated that about one-fifth of the total phospholipids are highly mobile. T1 and NOE measurements indicated that the differences in peak height for the 30.5 ppm resonance between normal and diseased muscle are due only to difference in the amount of highly mobile fatty acyl chains in the muscle and not due to differences in relaxation parameters. 13C NMR of isopentane-extracted muscle appears to permit differentiation of normal from diseased muscle and, within diseased muscle, grading of the severity of the disease.
Composition of pulmonary lavage fluid in control and reserpine-treated rats following chronic isoproterenol and pilocarpine administration.

Composition of Pulmonary Lavage Fluid in Control and Reserpine-treated Rats following Chronic Isoproterenol and Pilocarpine Administration
Dissolution Kinetics of E -Beam Resists

A brief overview of a model for the dissolution of resists is given. The glassy film is first converted into a swollen gel, whereupon entangled coils disengage from the network into the developer solution. The glass/gel interface movement is governed by stress-induced Case II diffusion, whereas polymer dissociation from the gel-like network at the gel/solvent interface is best described by a reptation type process. Transient stress and concentration profiles between these two moving boundaries provide a link between the interface kinetics. Polymer molecular weight, polymer-solvent compatibility, free volume state of the glassy matrix, and diffusivity of the solvent in the gel layer are all properly reflected in the basic scheme of the model. Preliminary results exhibit behavior consistent with experimental observations using an in-situ psi-meter. Effects of individual process parameters on the final structure will be explored in a future publication detailing comparison of full model predictions and systematic experimental data.
Relationships between Trawl Catch and Tow Duration for Penaeid Shrimp

Abstract The relationship between catch and trawling effort was explored for Penaeus aztecus, P. setiferus, and P. duorarum. Tow durations of 5, 10, 15, 20, 25, and 30 min bottom time were examined, and data were analyzed with orthogonal polynomials in a randomized complete block design. We found a significant linear relationship between catch and tow duration, which is consistent with the assumption of a constant catchability coefficient. However, tow duration accounted for only a small proportion of the total variation in catch. This indicates that catch-per-unit-effort indices of abundance may be improved when analyzed in statistical designs that consider other sources of variation in catch in addition to fishing effort. Scaling of catch data when tow durations vary is briefly discussed.
Immigration, the Public School, and the 20th Century American Ethos: The Jewish Immigrant As a Case Study

PM^R Explores the educational and societal experiences of the 20th century American immigrant by using the situation of the Jewish immigrant as a case study. Approaches such questions as: Did the schools promote or hinder immigrants' quest for the American Dream? Was, and is, the melting pot a myth or reality? and, Are there prices to pay for the American Drea
The relationship between the learning strategies and learning styles in a hypermedia environment

Abstract The relationship between hypermedia-assisted instruction and learners' different learning styles has prompted tremendous interest in educators because accommodating learners' different needs is one of the promises hypermedia technology is believed to hold. This study examined the different learning strategies by Field-independent (FI) people and Fielddependent (FD) people in a hypermedia assisted language learning setting. Sixty-three college, international students participated in the study. Findings that describe the different types of media, tools, and learning aids chosen by the FI and FD students were reported. Results from the study suggested that different learning style groups employed different learning strategies in accomplishing the same task. The results of the study indicated that the hypermedia technology has the potential to accommodate learners with different needs through its rich environment.
“A Tale of Two Václavs”: Rhetorical History and the Concept of “Return” in Post-Communist Czech Leadership

This article examines the ways by which former Czech president Vaclav Havel and former Czech Prime Minister Vaclav Klaus approached their rhetorical roles in the postcommunist climate of a splintering Czechoslovakia. The main argument revolves around how Klaus and Havel divergently employed national memory to make historical arguments about the Czech past and how these symbols could be marshaled to navigate the uncertain waters of postsocialism. Ultimately, Klaus employs a rhetorical strategy of “rupture” with the Czech communist past, while Havel attempts a strategy of “repair.” The tensions between such rhetorical strategies evidence the ways in which Czech intellectuals-turned-public officials vied for the position of chief public historian and national storyteller for the Czech nation.
Emulsion stabilization and flocculation in CO2. 2. Dynamic light scattering

Dynamic light scattering (DLS) was used to investigate steric stabilization and flocculation of dilute poly(2-ethylhexyl acrylate) (PEHA, Mw = 92K) emulsions in liquid CO2 at 25 °C by monitoring changes in droplet size over time at various CO2 densities. Two steric stabilizers were investigated: a homopolymer, poly(1,1-dihydroperfluorooctyl acrylate) (PFOA, Mw = 1 × 106), and a block copolymer, polystyrene (Mn = 4.5K g/mol)-b-PFOA (Mn = 25K). For a concentration of 0.03 wt %, aggregates of PS-b-PFOA were observed in CO2 with an average hydrodynamic diameter of approximately 80 nm and a polydispersity index of 0.2−0.3 from the method of cumulants. Critical flocculation densities (CFDs) of PEHA emulsions were determined by lowering the CO2 density at constant temperature to induce flocculation. The CFDs of the emulsions agree closely with the ϑ point density of PFOA in CO2 for both the homopolymer and block copolymer stabilizers. Above the CFD, the emulsions have an average droplet size of 400−600 nm and a...
The involvement of spinal Ca2+/calmodulin-protein kinase II in nicotine-induced antinociception in mice

The nature of the signaling process activated by neuronal nicotinic receptors has not been fully defined; however, several recent studies have implicated the involvement of Ca(2+) fluxes in the response to nicotine. In order to assess Ca(2+)-dependent mechanisms in nicotine-induced antinociception, the Ca(2+) channel antagonist nimodipine and several calcium/calmodulin-protein kinase II (CaM kinase II) inhibitors were evaluated for their effects on nicotine-induced antinociception. The results indicate that both of these antagonists dose-dependently blocked nicotine-induced antinociception after intrathecal (i.t.) injection. Indeed, three structurally unrelated CaM kinase II inhibitors blocked nicotine's effects in the tail-flick test in a dose-related manner. A second series of experiments assessed the effect of acute nicotine exposure on [Ca(2+)](i) and CaM kinase II activity in spinal cord tissues. Nicotine increased [Ca(2+)](i) in a concentration-dependent manner after application of the drug to spinal synaptosomes. Furthermore, a dose-dependent increase in the spinal cord membrane CaM kinase II activity was seen after acute injection of nicotine in mice. Taken together, these results are consistent with the hypothesis that nicotine binding to nicotinic receptors leads to channel opening and depolarization responses with an influx of Ca(2+) ions, which would reach sufficient levels to activate Ca(2+)-dependent/CaM kinase II. Neuronal Ca(2+), acting via Ca(2+)-dependent CaM kinase II, appears to mediate nicotine-induced antinociception at the spinal level.
Lesions of Experimental Genital Tritrichomonas foetus Infections in Estrogenized BALB/c Mice

Ninety-seven BALB/c mice were inoculated intravaginally with 8.0 x 10(5) Tritrichomonas foetus organisms, using either isolate ATCC 30003 or field isolate MU Y22 2 days after estrogenization with 15 micrograms 17 beta-estradiol. Reproductive tracts were examined at several time points post-inoculation to determine gross and histologic responses to trichomonad infection as compared to estrogenized, uninfected control animals. The two isolates varied greatly in ability to maintain chronic infection; no ATCC 30003-inoculated animals remained culture-positive beyond 7 weeks post-inoculation, whereas MU Y22-inoculated animals were infected for greater than 26 weeks. Lesions were seen in 40-60% of animals prior to 10 weeks post-inoculation and included moderate uterine dilation and glandular atrophy, uterine gland abscesses, pyometra, intramural perivascular lymphoid infiltrates, and ovarian bursitis. The severity of lesions was independent of the T. foetus isolate. Lesions became more severe at 10 weeks post-inoculation, and at 10 and 26 weeks post-inoculation, lesions were seen in 60% and 75% of animals, respectively. In addition to lesions described above, epithelial changes were marked at these late necropsies, including ulceration, flattening, hypertrophy, and squamous metaplasia. The lesions seen in these mice closely resemble those described in natural bovine infection, suggesting that the estrogenized BALB/c mouse is an excellent model for study of bovine trichomoniasis.
Structural characterization of the hydrocarbon degrading bacteria–oil interface: implications for bioremediation

Abstract Hydrocarbon degrading bacteria, enriched from an in situ bioremediation site in Long Valley, AZ emulsified and colonized the surface of waste engine oil. The application of a partial dehydration conventional embedding protocol for ultrathin-section transmission electron microscopy preserved the hydrocarbon degrading bacteria–surfactant–oil interface. Bacterial adsorption to oil occurred in association with a highly charged, amphipathic bacterial surfactant interface (25– 50 nm thick). This biosurfactant completely encapsulated the emulsified oil droplets demonstrating that less than 1% surfactant (by volume) is required to emulsify waste hydrocarbon during or to promote biodegradation. Growth on oil appeared to occur by the uptake of tens of nm-sized droplets of emulsified oil.
Comparative evaluation of air cell and eggshell temperature measurement methodologies used in broiler hatching eggs during late incubation.

ABSTRACT The current study was conducted to compare and contrast the uses of 2 devices (temperature transponder or infrared thermometer) and their locations (inner air cell membrane or outer eggshell surface) in Ross × Ross 708 broiler hatching eggs. The air cells of 14 embryonated and 10 nonembryonated eggs were implanted with temperature transponders on d 13.5 of incubation. Likewise, for these same eggs, eggshell surface temperature was detected with the use of transponders and an infrared thermometer. Temperatures were recorded every 12 h between 14.5 and 18 d of incubation, and graphs and corresponding regression values were used to track the temperatures over these time periods. The temperature readings using all methods in embryonated and nonembryonated eggs were positively correlated. In nonembryonated eggs, temperatures in the air cell and on the eggshell surface using transponders were higher than those on the eggshell surface using an infrared thermometer. Mean air cell temperature readings of embryonated eggs using transponders were higher than those of the eggshell, as determined with the use of transponders or an infrared thermometer. Furthermore, the differences in air cell temperature using transponders and eggshell temperature using an infrared thermometer in embryonated eggs increased with embryonic age. These readings confirmed increased embryo heat production during the incubational period examined. It was further concluded that when compared with actual embryo body temperatures determined in previous studies, the use of transponders in the air cells of broiler hatching eggs detected a higher and closer temperature than eggshell surface temperature. It is suggested that the air cell transponders in embryonated eggs circumvented the confounding effects of the thermal barrier properties of the eggshell and the flow of air across its surface.
Pretransplant anti-HLA-Cw and anti-HLA-DP antibodies in sensitized patients

We investigated the prevalence and the strength of anti-HLA-Cw and DP antibodies and clinical outcomes in kidney transplant recipients with isolated donor-specific anti-HLA-Cw antibodies. Patients on the waiting list were screened by Luminex single antigen beads (One Lambda). The strength of antibodies was determined by mean fluorescence intensity (MFI) values of the beads. Of the 1069 patients on the waiting list, 251 (24%) were sensitized with calculated panel reactive antibody >0%. The frequency and the median MFI values of anti-HLA antibodies to Cw (56%, 4955) and DP (35%, 2945) were lower than anti-HLA-A (79%, 10,194), B (86%, 11,235), DR (66%, 7866) and DQ (69%, 8283) (p<0.01). Among three major sensitizing events, only previous transplant was associated with development of all anti-HLA antibodies and history of pregnancy was associated only with development of anti-HLA-A antibodies. Eight patients with donor-specific anti-HLA-Cw antibodies received transplantation. During a median 6 months of follow-up (range 3-24 months), patient and graft survival was 100% without any acute rejection. In summary, the prevalence and the strength of anti-HLA-Cw and HLA-DP were lower compared to anti-HLA-A, B, DR, and DQ antibodies and previous organ transplantation was the main sensitizing event in our cohort of patients.
Nerve fiber requirements for regeneration in forelimb transplants of the newt Triturus.

Abstract The dependence of limb regeneration on the number of nerve fibers at the amputation surface was examined further in studies of the nerve requirements for regeneration in transplants of the upper arm to the back. In time, the grafts were reinnervated by local fibers and in some of the experiments by brachial nerves that were deviated to the site of transplantation. Counts of nerve fibers at the original regenerating surface of the graft showed that far fewer fibers can induce growth than are required for regeneration of the normal limb. Therefore, the threshold nerve requirements for regeneration are not fixed but vary with the capacity of the wound tissue to respond to nervous stimulation. The ability to respond is increased in the would tissues of the graft presumably by the trauma of transplantation. The role of the wound tissues in establishing the threshold nerve requirements and possibly in contributing substances important for regeneration are discussed.
Recurrent nontuberculous mycobacterial endophthalmitis: a diagnostic conundrum.

Objective To report a case of recurrent nontuberculous mycobacterial endophthalmitis in the context of neurotrophic keratopathy secondary to herpes zoster ophthalmicus that had an atypical presentation and complex course, and highlights the challenges of causative organism identification and therapeutic interventions in this condition. Methods A retrospective chart review was conducted to determine the visual outcomes of the patient. Results A 68-year-old pseudophakic male with long-standing neurotrophic keratopathy and perforated descemetocele managed with cyanoacrylate glue and a contact bandage lens in the left eye, began experiencing recurrent episodes of endophthalmitis after undergoing a penetrating keratoplasty. Several therapeutic procedures including an anterior chamber washout, two pars plana vitrectomies, explantation of the posterior chamber intraocular lens and capsular bag, and multiple intravitreal antimicrobial injections, were performed to which he has ultimately responded favorably, with no signs of infection to date and stable visual acuity. The causative organism of his recurrent infections was initially identified as Mycobacterium abscessus through biochemical testing and 16S ribosomal ribonucleic acid gene sequencing; however, repeat polymerase chain reaction (PCR) and sequencing of the 65 kDa heat shock protein (hsp65) gene for experimental purposes confirmed the accurate identification of the organism to be Mycobacterium chelonae. Given the greater reliability of PCR and sequencing of the hsp65 gene over traditional biochemical tests and culture techniques, M. chelonae was likely the infectious agent all along, and the organism was originally misidentified on the basis of less accurate tests. Conclusion Recurrent atypical mycobacterial endophthalmitis requires expedient identification and management to prevent poor visual outcomes. Standard biochemical testing can identify the causative organism but is limited by the inability to distinguish between nontuberculous species reliably. We recommend the use of PCR in conjunction with sequencing of the hsp65 gene for reliable differentiation of M. chelonae and M. abscessus in atypical mycobacterial ocular infections. Minimum inhibitory concentration antibiotic susceptibility tests on cultured strains are the best guide to antibiotic selection, given the rapidly rising resistance to antimicrobials in atypical mycobacterial species.
Quality of life in treatment of hypertension. A metaanalysis of clinical trials

A metaanalysis was performed to determine the effects on quality of life (QL) in hypertension as reported in published clinical trials of antihypertensive drug therapy. All studies included compared active treatment to baseline (placebo or no treatment) with the patients as their own control and used blinded, randomized trials. Change was measured by self and/or interviewer-assisted evaluation, standardized psychomotor/cognitive tests, or sleep laboratory observations. After an exhaustive literature search (1970 to 1990), nine published trials of 27 population groups (n = 1620) using 14 drugs from six pharmacological groups met selection criteria and were analyzed for five QL constructs: sexual function, sleep, psychomotor, general well-being, and mood. Small positive effect size (d) improvement with treatment was seen for sleep (d = 0.106), psychomotor (d = 0.283), general well-being (d = 0.139), and mood (d = 0.167) while no effect could be determined for sexual function (d = -0.030) based on 95% confidence intervals. Either a comparably small improvement with treatment or no effect was seen among various pharmacological drug groups; no negative effect with treatment was identified. A larger positive effect could be postulated if the drug choice was individualized to the patient rather than randomized as in clinical trial methodology. Although none of the drug groups had a clearly superior effect, a more frequent positive effect with angiotensin converting enzyme inhibitors and beta-blockers was seen for all constructs. Narrower demographics and smaller sample sizes may have biased similar positive effects in calcium-channel blockers and diuretics.
Selective attention to global and local structure of objects : alternative measures of nontarget processing

When individuals are asked to report either the global or the local level of structure in a stimulus pattern located inside a relevant object, distractors located within an irrelevant object will interfere only if they are at the same level of structure as that of the target item (Briand, 1993; Paquet & Merikle, 1988). The basis of this level-specific filtering is unclear, as is the true level of semantic analysis for the ignored items. In the present series of experiments, multiple measures of nontarget processing were used to assess concurrent interference, negative priming, and a category effect supposedly reflecting a more abstract level of semantic analysis. These different indicants were assessed in three experiments in which form, color, or a spatial precue was used to direct attention to the relevant stimulus pattern. Overall, cuing by form produced poorer spatial selectivity, whereas spatial precues and color led to better selectivity. However, the three measures of nontarget processing were not equally affected by these manipulations, with global information showing more evidence for semantic analysis than for local analysis regardless of the type of selection cue used. The results suggest that inhibition is not the basis of target selection when ignored items are local, but that it may be used when global items are ignored.
Potential role of soil calcium in recovery of paper birch following ice storm injury in Vermont, USA

In recent years, an increased number of mature paper birch (Betula papyrifera Marsh.) and heart-leafed paper birch (B. papyrifera var. cordifolia (Regel) Fern.) in northeastern United States forests have exhibited decline symptoms including foliar loss, reduced fine branching, and tree mortality. We assessed crown health, radial growth, and available soil cations in 2006 as a preliminary assessment of factors that may be influencing paper birch decline. Tree rings began to decrease in width in 1998--the year of a severe region-wide ice storm. All trees (regardless of their current decline status) experienced reduced growth starting in 1998 and tree growth continued to decrease for two years following the ice storm. After this generalized growth decrease, trees that now have vigorous crowns showed a marked increase in growth, whereas trees that now have low crown vigor did not rebound in growth, but instead exhibited a significantly higher incidence of locally absent annual rings. Extractable soil-aluminum (Al), a phytotoxic element mobilized by acid deposition, was significantly higher in soils associated with declining trees compared to those adjacent to vigorous trees. Higher soil calcium (Ca) availability was associated with both vigorous crowns and increased radial growth following the 1998 ice storm. Furthermore, increased soil Ca availability was negatively correlated to the percentage of declining trees, and positively related to increased radial growth, whereas elevation was not significantly associated with either parameter. Although previously overlooked as a factor influencing paper birch recovery from injury, we found that available soil Ca was linked to crown vigor and rebounds in growth following an inciting event.
Mandating Two-Year Regional Anesthesia Fellowships: Fanning the Academic Flame, or Extinguishing It?

A discussion is unfolding within anesthesiology regarding the apparent demise of anesthesiology physician scientists in academic medicine. Although not addressing regional anesthesia specifically, an article in the journal Anesthesiology by Drs. Debra Schwinn and Jeffrey Balser presented persuasive evidence that our specialty—as a whole—is failing to adequately train future physician scientists and has an abysmally-small percentage of “NIH [National Institutes of Health] grants relative to other specialties.”1 As a consequence, anesthesiology is “at risk of losing its status as a respected academic discipline within the broader biomedical community.”1 Subsequent editorials2;3 and multiple letters-to-the-editor4-7 unanimously agreed that “academic anesthesiology is indeed in a crisis, and that bold steps are needed to avert the demise of our specialty as a legitimate academic discipline.”8 Drs. Schwinn and Balser's “main solution is to establish an increase in subspecialty fellowships that incorporate at least 1 year of research.”5 They note that, “exposure to a rigorous research environment whets the appetite for research in many individuals who would otherwise not have been exposed;” and that none of our fellowships “have a research requirement (although some have such a recommendation), in contrast to those of our peer specialties.”1 They add that, as a specialty, we “set extraordinarily low expectations in regard to the research accomplishments of our finest trainees at the terminal phase of their training.”1 These authors explain that they were “in the end offering an opinion that deserves to be challenged,” and invited “others to consider our position in light of other alternatives for ‘corrective action,’ and to advocate for these positions.”1 We concur with our colleagues that “only through such discourse will we make progress.”8 And while we agree that the crisis in anesthesiology is not only severe but growing, we propose that mandating at least one year of fellowship training devoted exclusively to research may actually be counterproductive for regional anesthesia fellowships at this time. As with any policy change, the cost-benefit ratio must be examined when considering an intervention of this magnitude.
Single Image X-Ray Photogrammetry System Used To Detect Total Joint Loosening

Loosening is the number one complication of total joint replacements. A direct method of measuring small motions between the prosthetic implant and the surrounding bone would allow the surgeon to evaluate replacement surgery or activity restrictions. Single plane x-ray photogrammetry uses stainless steel markers in the bone and prosthetic implant and a control frame in order to accomplish this measurement. Testing of models representing a total hip replacement and total knee replacement has shown that displacements can be measured with a root mean square error of less than 0.2 mm.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The effect of hot dense hydrogen and argon in a ballistic compressor on the structure and composition of pure iron

Abstract A preliminary experimental study of pure iron foil exposed to a hot, dense hydrogen and argon gas mixture in a ballistic compressor yielded evidence for new structural and compositional changes in the metal due to the exposure. Atomic force microscopy (AFM) demonstrated that the hydrogen-exposed surface was highly uneven, where height variations were as much as 2 μm for many of the micron-sized regions scanned. Optical microscopy and scanning electron microscopy found that this sample contained unusual “V” and “W” shaped lines with some individual line segments reaching over 60 μm. Also, a relatively large carbon peak was found to exist from energy dispersive X-ray spectrometer data. An iron foil exposed to argon gases alone revealed unique dendritic patterns but never showed micron-size height variations when imaged at a similar scale. This sample is also blue in color, and appears to form a thicker oxide layer over its surface than that of the former sample. The unexposed sample showed no height variations and no dendritic patterns of any kind. The “V” type configurations were never seen on either of the latter two samples.
Bimetallic dispersed sulfide catalysts from organometallic clusters for coal liquefaction

Several heterometallic complexes consisting of Mo, Co and sulfur in a single molecule were synthesized and tested as precursors of dispersed catalysts for liquefaction of a subbituminous coal. The structure of the precursors, in particular the type of ligands to the metal species, significantly affects the activity of the bimetallic MoCo sulfide catalysts generated in situ. Among the M-M′ type precursors tested, Mo-Co thiocubane, Mo2Co2S4(Cp)2(CO)2 (Cp = cyclopentadiene), produced the best catalyst.
Gender differences in family and peer reaction to the adoption of a vegetarian diet

Although ethical vegetarianism has been the subject of considerable theoretical attention and debate among feminists, the subject has received little empirical attention. This research note summari...
Gas chromatographic determination of chlorobenzenes and other chlorinated hydrocarbons in environmental samples using fused silica capillary columns

In order to assess the pathways of chlorinated benzenes and toluenes, hexachlorobutadiene and polychlorinated biphenyls in the environment capillary gas chromatographic methods have been developed for analysis of water, sediments and biological samples. Compound recoveries are reported from water, using liquid-liquid extraction with hexane, and from sediments and fish, using soxhlet extraction with hexane/acetone. After suitable cleanup, hexane extracts are chromatographed on a duel fused silica column arrangement (OV1 and SE54 with electron capture detectors for quantitation. The application of these procedures to environmental analysis is discussed.
Self-reported interference with academic functioning and eating disordered symptoms: Associations with multiple dimensions of body image

A sample of 1583 undergraduates completed a multidimensional measure of body image (Multidimensional Body-Self Relations Questionnaire, MBSRQ) and a new scale, the Eating and Body Image Disturbances Academic Interference Scale (EBIDAIS). All five subscales of the MBSRQ were related to higher levels of self-reported interference with academic functioning in correlational analyses. For the entire sample, a regression revealed that only the appearance orientation subscale of the MBSRQ did not explain unique variance associated with EBIDAIS scores. A few gender differences emerged when separate regressions were conducted, however, overweight preoccupation was the variable that predicted the largest unique variance for both genders. The results suggest that academic interference should be considered as a possible variable when evaluating the social and occupational problems associated with body image disturbance.
A hybrid expert system-neural networks methodology for anticipatory control in a process environment

A methodology is presented that couples expert systems to neural networks for the purpose of monitoring and control in a process environment. This is achieved within the framework of the anticipatory paradigm. The basic assumption of the anticipatory paradigm is that a complex system can modify its behavior on the basis of present as well as anticipated future states. The complex systems contemplated in this research use measures of performance to represent current as well as anticipated states in such a manner that decisions about change of state are related to a search for maximizing the performance associated with a state variable. Current performance is computed on the basis of a comparison between measured(sensor) and calculated(model) data. Anticipated performance is computed on the basis of predictions made by pre-trained neural networks. A fuzzified Bayes formula is used as the computational link between present and future states. The implementation of such a system calls for a coupling between expert systems(ESs) and artificial neural networks(ANNs). This coupling allows a knowledge-based system to make control decisions through an assessment of the current performance of the process and an estimate of its anticipated performance a Dt time latter; pre-trained neural networks provide fast estimates of future states.
Maintaining native arteriovenous fistulas for dialysis access

Complications of all types of vascular dialysis access are a major source of morbidity and expense, approaching $8000 per patient per year at risk. Many studies have compared the patency and durability of native arteriovenous fistulas (AVFs) versus that of synthetic bridge grafts composed of polytetrafluoroethylene (PTFE). Initially, AVFs appear to have a higher degree of cumulative patency when compared with PTFE grafts. However, when active access surveillance programs are used, the cumulative patency of both types of access appears similar. Many more interventions are necessary for the PTFE graft to match the patency of the AVFs. There are many configurations of AVFs that can be constructed to take advantage of the available venous anatomy. Interventional procedures involving the AVFs are more technically challenging than those involving PTFE grafts. Technical success in treating occluded AVFs is slightly less than with PTFE grafts (range, 81% to 95% vs. 89% to 100%, respectively). Thrombolysis can be performed with a bolus of 10 mg rt-PA (Genentech, Inc, South San Francisco, CA) or 5 units of reteplase (Centocor, Malvern, PA). This is followed by infusion of 2 to 4 mg per hour rt-PA or 1 unit of reteplase per hour. All patients are heparinized. Mechanical thrombectomy with various aspiration or clot-disrupting devices can be used alone or with lytic therapy to clear the access. Angioplasty is then used to treat stenoses. Complications of intervention include rupture of the vein with or without loss of the fistula, and embolization of thrombus into the native arterial system, which may produce symptomatic ischemia and infection. Although treatment of complications of AVFs is more challenging than with PTFE grafts, the success rate and cumulative patency iustifies their use.