cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of mutant SOD1 disulfide oxidation and aggregation in the pathogenesis of familial ALS

Transgenic mice that model familial (f)ALS, caused by mutations in superoxide dismutase (SOD)1, develop paralysis with pathology that includes the accumulation of aggregated forms of the mutant protein. Using a highly sensitive detergent extraction assay, we traced the appearance and abundance of detergent-insoluble and disulfide cross-linked aggregates of SOD1 throughout the disease course of SOD1-fALS mice (G93A, G37R, and H46R/H48Q). We demonstrate that the accumulation of disulfide cross-linked, detergent-insoluble, aggregates of mutant SOD1 occurs primarily in the later stages of the disease, concurrent with the appearance of rapidly progressing symptoms. We find no evidence for a model in which aberrant intermolecular disulfide bonding has an important role in promoting the aggregation of mutant SOD1, instead, such cross-linking appears to be a secondary event. Also, using both cell culture and mouse models, we find that mutant protein lacking the normal intramolecular disulfide bond is a major component of the insoluble SOD1 aggregates. Overall, our findings suggest a model in which soluble forms of mutant SOD1 initiate disease with larger aggregates implicated only in rapidly progressing events in the final stages of disease. Within the final stages of disease, abnormalities in the oxidation of a normal intramolecular disulfide bond in mutant SOD1 facilitate the aggregation of mutant protein.
The Construction of Retrieval Environments and Pseudo-Classifications Based on External Relevance.

Abstract The idea of pseudo-classification based on external relevance is introduced and compared with the more usual classifications derived by associative techniques. A general model for an information retrieval system using term classification is described. The derivation of a set of operators, or perturbations, for adjusting pseudo-classifications and preventing their deterioration is given for a particular match function conforming with this model. The use of pseudo-classifications both for the prediction of relevant documents and for the evaluation of retrieval systems with respect to their theoretical optimum is discussed. The concept of the improvability of a retrieval model with respect to its constituent submodels is introduced and elaborated upon. This report is the result of research conducted on classification techniques for informational retrieval systems supported in part by a grant from the Office of Scientific Information Service of the National Science Foundation to the Computer and Information Science Research Center, The Ohio State University.
Pure rotational transitions in the ν3 state of methane

Abstract Pure rotational transitions of methane in the ν3 state have been observed by infrared-microwave double resonance spectroscopy. A total of 15 transitions among the tetrahedral fine structure components of the Coriolis sublevels were measured. A tunable color center laser was used as the infrared radiation source, and a synthesized centimeter wave signal generator operating between 11.5 and 17.5 GHz was used as the microwave source. The frequencies, measured to better than 50 kHz, are compared to frequencies calculated from combination differences of the most precise infrared frequencies.
Adrenal dynamic responses to physiologic and pharmacologic adrenocorticotropic hormone stimulation before and after ovarian steroid modulation in women with polycystic ovary syndrome.

Abstract Objective: To test the hypothesis that in women with polycystic ovary syndrome (PCOS), adrenal cytochrome P450c 17α activity is different after physiologic vs. pharmacologic ACTH stimulation and that ovarian activity promotes adrenal hyperactivity that is different after physiologic vs. pharmacologic ACTH stimulation. Design: Prospective controlled pilot study. Setting: Reproductive endocrinology unit of an academic medical center. Patient(s): Six women with PCOS who had adrenal hyperandrogenism were compared with four women with normal ovulation. Intervention(s): Adrenal dynamic blood sampling was performed before and after 6 months of GnRH agonist administration. Main Outcome Measure(s): Comparison of physiologic and pharmacologic ACTH-stimulated levels of progesterone, 17-hydroxyprogesterone, and androgens before and after ovarian steroid modulation. Result(s): In women with PCOS, exaggerated responses of androstenedione and 11β-hydroxyandrostenedione as well as elevated ratios of 17-hydroxyprogesterone to progesterone and of androstenedione to 17-hydroxyprogesterone after physiologic ACTH stimulation did not persist after GnRH-agonist administration. Three of the six women with PCOS had an increased response of androstenedione and a ratio of androstenedione to 17-hydroxyprogesterone that were >2 SD above the mean of those in the women with normal ovulation after pharmacologic ACTH stimulation; this finding persisted after GnRH-agonist administration. Conclusion(s): In women with PCOS, increases in adrenal androgen sensitivity after physiologic ACTH stimulation reflected in both arms of cytochrome P450c 17α activity may be influenced by ovarian activity. However, 17,20-lyase hyperactivity in a subset after pharmacologic ACTH stimulation may be an intrinsic adrenal disorder.
Light exposure stimulates arachidonic acid metabolism in intact rat retina and isolated rod outer segments.

This paper presents evidence that short-term exposure to light increases synthesis of hydroxyei-cosatetraenoic acid (HETE) and prostaglandin D2 (PGD2) and stimulates the uptake and metabolism of 20∶4 in phospholipids and triacylglycerols in rat retina. There was a time-dependent increase in incorporation of 1-14C-20∶4 into glycerolipids in both dark-adapted and light-exposed groups. Exposure to light for 15 or 30 min enhanced the acylation of 20∶4 into phosphatidylcholine, phosphatidylinositol, phosphatidylethanolamine and triacylglycerols. In the light-exposed groups there was a large increase in the conversion of 20∶4 to leukotriene B4, two diHETEs, 5-HETE, 15-HETE, and PGD2. The stimulation of HETE synthesis by light could be due to early stages of light-induced lipid peroxidation in visual cells. To examine this, we studied peroxidation of 20∶4 in isolated rod outer segments (ROS). There was more oxidation of 20∶4 in light-exposed ROS, as compared to ROS incubated in the dark. Vitamin E and nordihydroguaiaretic acid inhibited the light-induced formation of some of these products. The data indicate that photo-oxidation of 20∶4 in ROS is accompanied by enzymatic oxygenation that is stimulated by light. Increased production of HETEs and PGD2 may be a consequence of the light-induced stimulation of the metabolism of 20∶4 in membrane phospholipids in the retina.
Thermal Transitions of Salt-soluble Proteins from Pre- and Postrigor Chicken Muscles

Salt-soluble protein (SSP) was extracted from pre- and postrigor chicken muscles at various pH values, and protein thermal denaturation was studied using several techniques. Heating at 1°C/min from 20 to 70°C induced a three- to fourfold increase in breast and leg hydrophobicity. Differential scanning calorimetry of breast and leg SSP showed a major transition occurring within the range 55 to 64°C, with the value dependent on rigor state and pH. Protein-protein association, as measured by turbidity change upon heating, underwent two transitions for leg SSP and two or three for breast SSP. The specific transition temperature and rate were dependent on pH, muscle type and rigor state. However, muscle type and pH had a greater effect than muscle rigor state on SSP denaturation.
The author responds: Popper and selection theory

(1988). The author responds: Popper and selection theory. Social Epistemology: Vol. 2, No. 4, pp. 371-377.
More jobs for the boys? Succession planning in SMEs

Both the incidence of planning and the identification of female successors were lower than anticipated in this study of 128 companies with less than 50 employees. No company selected a female successor despite strong existing candidates, whether relatives or internal managers. Daughters were inappropriate for succession – they were “too good” for the workplace or were “doing something better”, i.e. teaching, health care, etc. Although female relatives benefited from resources for holidays or home improvements, only male relatives were seen as “heirs apparent” in terms of work status and treatment. Female relatives were neither developed nor encouraged as managers, despite frequently acting as mentors and trainers for the selected male successor. Views of successors and non‐successors are expressed and concerns for policy‐makers identified given the potential disappearance of firms without successors, and the neglect of available potential female managers.
Property values and pension underfunding in the local public sector

Abstract This paper reexamines the empirical implication of the C. Tiebout (J. Pol. Econ. 64, 416–424 (1956)) hypothesis, taking account of the fact that many municipal pensions are grossly underfunded. OLS results show that underfunding has no impact on local property values. The motives for incomplete funding of pensions are also examined and are built into a simultaneous equation model. The OLS results are confirmed and some light is shed on factors leading to the underfunding of pensions.
Hyperglycemia and diabetes mellitus in children with pancreatitis.

Objective To assess the risk factors for developing hyperglycemia and diabetes mellitus (DM) in children with pancreatitis. Study design Patients (from infants to age 21 years) hospitalized with acute pancreatitis (AP), acute recurrent pancreatitis (ARP), and chronic pancreatitis were studied retrospectively. Subjects with known DM or cystic fibrosis before presentation with pancreatitis were excluded. Results A total of 176 patients met the study criteria. Of these, 140 had AP, 29 had ARP, and 7 had chronic pancreatitis. Severe pancreatitis was associated with hyperglycemia; 41% of the patients with hyperglycemia required insulin, and 8 patients (4.5%) developed DM requiring insulin by the time of discharge. These 8 patients with postpancreatitis DM were more likely to be overweight. Five of the 8 patients had a seizure disorder, and 4 had another comorbidity, such as mental retardation or cerebral palsy. Seven of the 8 patients who developed DM had a single episode of AP, and one patient had ARP. Conclusions Our findings indicate that hyperglycemia and DM can occur with pancreatitis. In some cases, postpancreatitis DM was associated with mental retardation, seizure disorder, and use of antiseizure medication. As opposed to adults who develop DM after chronic pancreatitis, children can develop DM due to a single episode of AP.
Arabidopsis emb175 and other ppr knockout mutants reveal essential roles for pentatricopeptide repeat (PPR) proteins in plant embryogenesis

Pentatricopeptide repeat proteins (PPRPs) constitute one of the largest superfamilies in plants, with more than 440 identified in the Arabidopsis thaliana (L.) Heynh genome. While some PPRPs are known to take part in organelle gene expression, little is known about the broader biological contexts of PPRP gene function. Here, using developmental- and reverse-genetic approaches, we demonstrate that a number of PPRPs are essential early in plant development. We have characterized the Arabidopsis embryo-defective175 mutant and identified the EMB175 gene. Emb175 consistently displays aberrant cell organization and undergoes morphological arrest before the globular-heart transition. The emb175 mutation disrupts an intronless open reading frame encoding a predicted chloroplast-localized PPR protein— the first to be rigorously associated with an early embryo-lethal phenotype. To determine if other PPRP genes act in embryogenesis, we searched Arabidopsis insertion mutant collections for pprp knockout alleles, and identified 29 mutants representing 11 loci potentially associated with embryo-defective phenotypes. We assessed gene structures, T-DNA insertion position, and allelism for these loci and were able to firmly establish essential functions for six PPRP genes in addition to EMB175. Interestingly, Nomarski DIC microscopy revealed diverse embryonic defects in these lines, ranging from early lethality to dramatic late-stage morphological defects such as enlarged shoot apices and stunted cotyledons. Together, emb175 and these pprp knockout mutants establish essential roles for PPRPs in embryogenesis, thus broadening the known organismal context for PPRP gene function. The diversity of emb–pprp knockout phenotypes indicates that mutation of different PPRPs can, directly or indirectly, have distinct impacts on embryo morphogenesis.
Dynamic properties of cat tenuissimus muscle

Some of the factors which influence the development of tension in cat tenuissimus muscle were studied quantitatively. Under isometric conditions, it was shown that the dynamic properties of the relationship between the tension of the muscle and its electrical stimulation depend on the mean rate of stimulation. This non-linear effect cannot be explained on the basis of the dependence of muscle tension on instantaneous rate of stimulation since the tension due to a stimulus following closely a previous stimulus is augmented, but the time course of the twitch response is unaltered. The interaction between the tension due to active contraction and that due to the viscoelastic properties of the muscle was investigated by independently varying muscle length and the rate of stimulation. Within the limits of resolution of the data, it was concluded that these two components of tension are additive and that muscle stiffness is related to the instantaneous tension of the muscle.
On Adaptive Regularization Methods in Boosting

Boosting algorithms build models on dictionaries of learners constructed from the data, where a coefficient in this model relates to the contribution of a particular learner relative to the other learners in the dictionary. Regularization for these models is currently implemented by iteratively applying a simple local tolerance parameter, which scales each coefficient toward zero. Stochastic enhancements, such as bootstrapping, incorporate a random mechanism in the construction of the ensemble to improve robustness, reduce computation time, and improve accuracy. In this article, we propose a novel local estimation scheme for direct data-driven estimation of regularization parameters in boosting algorithms with stochastic enhancements based on a penalized loss optimization framework. In addition, k-fold cross-validated estimates of this penalty are obtained during its construction. This leads to a computationally fast and effective way of estimating this parameter for boosting algorithms with stochastic en...
Optics of a two-trough solar concentrator

A linear focusing solar concentrator is described that uses two reflecting troughs, one is a large, stationary hemi-cylinder and the other is small and tracks the sun. The small reflector weighs less than a parabolic trough with the same concentrator aperture therefore diurnal steering is more feasible. Energy is carried to the job by solar heated fluid in a pipe at focus in the secondary reflector assembly. Theory is presented and comparisons are given for east-west and north-south oriented parabolic and two-trough collectors. In the ideal world, the parabolic outperforms the two-trough collector however in the real world, the simplifications due to the immobile, hemi-cylinder, large reflector may outweigh its disadvantages.
Do Children With Blunt Head Trauma and Normal Cranial Computed Tomography Scan Results Require Hospitalization for Neurologic Observation

Study objective Children evaluated in the emergency department (ED) with minor blunt head trauma, defined by initial Glasgow Coma Scale (GCS) scores of 14 or 15, are frequently hospitalized despite normal cranial computed tomography (CT) scan results. We seek to identify the frequency of neurologic complications in children with minor blunt head trauma and normal ED CT scan results. Methods We conducted a prospective, multicenter observational cohort study of children younger than 18 years with blunt head trauma (including isolated head or multisystem trauma) at 25 centers between 2004 and 2006. In this substudy, we analyzed individuals with initial GCS scores of 14 or 15 who had normal cranial CT scan results during ED evaluation. An abnormal imaging study result was defined by any intracranial hemorrhage, cerebral edema, pneumocephalus, or any skull fracture. Patients with normal CT scan results who were hospitalized were followed to determine neurologic outcomes; those discharged to home from the ED received telephone/mail follow-up to assess for subsequent neuroimaging, neurologic complications, or neurosurgical intervention. Results Children (13,543) with GCS scores of 14 or 15 and normal ED CT scan results were enrolled, including 12,584 (93%) with GCS scores of 15 and 959 (7%) with GCS scores of 14. Of 13,543 patients, 2,485 (18%) were hospitalized, including 2,107 of 12,584 (17%) with GCS scores of 15 and 378 of 959 (39%) with GCS scores of 14. Of the 11,058 patients discharged home from the ED, successful telephone/mail follow-up was completed for 8,756 (79%), and medical record, continuous quality improvement, and morgue review was performed for the remaining patients. One hundred ninety-seven (2%) children received subsequent CT or magnetic resonance imaging (MRI); 5 (0.05%) had abnormal CT/MRI scan results and none (0%; 95% confidence interval [CI] 0% to 0.03%) received a neurosurgical intervention. Of the 2,485 hospitalized patients, 137 (6%) received subsequent CT or MRI; 16 (0.6%) had abnormal CT/MRI scan results and none (0%; 95% CI 0% to 0.2%) received a neurosurgical intervention. The negative predictive value for neurosurgical intervention for a child with an initial GCS score of 14 or 15 and a normal CT scan result was 100% (95% CI 99.97% to 100%). Conclusion Children with blunt head trauma and initial ED GCS scores of 14 or 15 and normal cranial CT scan results are at very low risk for subsequent traumatic findings on neuroimaging and extremely low risk of needing neurosurgical intervention. Hospitalization of children with minor head trauma after normal CT scan results for neurologic observation is generally unnecessary.
Epistemic honesty and the default assumption that photos are true

Most magazine editors rely on readers to assume that a photo has not been significantly altered unless labeled otherwise. That reliance helps continue the longstanding fallacy that there is such a thing as a prealteration state of photography that is natural and truthful. This article sees a need for epistemic honesty, information added to help the receiver judge the truth or accuracy of a piece of communication. It looks to verbal language and the quotation as models for the honest presentation of samples of reality. The result is a recommendation for a visual equivalent to the quotation mark to alert the reader that a photo meets a certain standard of truthfulness.
Micro-Macro Modeling of Continuous Cast Steel to Simulate the Effect of Casting Velocity and Pouring Temperature on Copper Segregation

One of the most serious problems in using recycled scrap for steel production is the occurrence of surface hot shortness during hot deformation due to the presence of copper in scrap. Copper causes surface hot shortness by liquid embrittlement. Therefore, the amount of the liquid copper-enriched phase penetrating into the grain boundaries should be identified in order to keep its effects within acceptable limits. In this regard, understanding the mechanism of segregation during solidification of steel is essential. This paper attempts to demonstrate micro-macro modeling of continuous cast steel to simulate the effect of casting velocity and pouring temperature on copper segregation. First, the temperature profiles at different times were determined using a finite element (macro) model and a segregation (micro) model based on Giovanola-Kurz approach is coupled with the macro model. It is necessary to couple the heat flow calculations from the macro model and the segregation calculations from the micro model because the rate of latent heat liberation is affected by the solute redistribution process, while the solute redistribution process depends on the cooling rates. As the casting velocity and pouring temperature strongly affect the solidification of continuous cast steel, they were chosen as the variables in this study. It is hoped that this study will enable the optimization of these variable to minimize the segregation of copper. This paper also demonstrates that by decreasing casting velocity and pouring temperature of a steel billet during continuous casting, solid-liquid interface moves faster to the center of the billet and there is less chance for diffusion of the residual elements in steel. Therefore, the chance of hot shortness of copper in the steel increases.Copyright © 2012 by ASME
Clinical and pathological features of aortic thromboembolism in 36 dogs

Thirty-six dogs with aortic thromboembolism were identified in a retrospective study conducted using case material from the small animal necropsy service of the University of Pennsylvania, from 1977 through 1992. No age, breed, or sex predisposition was found. Thirty dogs presented with primary complaints referable to the aortic thromboembolus and the duration of signs varied from hours to months. In 16 dogs, the presence of the thromboembolus was confirmed antemortem by ultrasound or angiography. Coagulograms were performed in 11 animals, and were consistent with consumptive hemostatic disorders in 8. The aortic occlusions were determined to be emboli in 11 dogs, associated with cardiac disease (9 dogs) and neoplastic emboli (2 dogs). In 18 dogs, the aortic occlusions were determined to be caused by primary aortic thrombi. Nine of these dogs had renal disease and four dogs had severe atherosclerosis associated with thyroid disease. In seven dogs, it could not determined if the aortic occlusions were due to primary aortic thrombi or due to emboli. In 25 dogs, the aorta was the only vessel occluded; but in 11 dogs, thrombi were identified in vessels outside of the systemic arterial system. In 9 dogs, the pulmonary arteries contained thromboemboli; one dog had thrombi in the portal vein and pulmonary arteries, and one dog a cranial vena caval thrombus. Nine of 11 dogs with multiple vascular thrombi, as well as some of the dogs with primary aortic thrombi, may have had either a propensity for thrombosis (a hypercoagulable state) or an inability to lyse thrombi (a hypothrombolytic state).
Custodial symmetry and the triviality bound on the Higgs mass

Abstract The triviality of the scalar sector of the standard one-doublet Higgs model implies that it is only an effective low-energy theory valid below some cut-off scale Λ. In this note we show that the experimental constraint on the amount of custodial symmetry violation, |Δϱ ∗ | = α|T| ≤ 0.4% , implies that the scale Λ must be greater than of order 7.5 TeV defined about the infrared-stable Gaussian fixed-point, we estimate that this lower bound on Λ yields an upper bound of approximately 550 GeV on the Higgs boson's mass, independent of the regulator chosen to define the theory. We also show that some regulator schemes, such as higher-derivative regulators, used to define the theory about a different fixed-point are particularly dangerous because an infinite number of custodial-isospin-violating operators become relevant.
Peptide Nanocapsules and Their Conjugation with Inorganic Nanoparticles

Inorganic nanoparticles such as colloidal gold, quantum dots or superparamagnetic iron oxide nanoparticles have unique optical and magnetic properties for a wide variety of biomedical applications. Here we present the design and biophysical analysis of a novel type of self-assembling polypeptide nanocapsule (SAPN), which can be used to encapsulate such inorganic nanoparticles. The peptide chain is composed of the pentameric coiled-coil domain at the N-terminus and a trimeric coiled-coil domain at the C-terminus. At either end a functional peptide sequence can be attached to provide useful biological functions for cell targeting or cell penetration. The SAPN are formed in a self-assembly process of the coiled-coil oligomerization domains. The central cavity of the SAPN can be modified with positively charged residues making it ideally suited for encapsulation of inorganic nanoparticles which are coated with negatively charged ligands. We have successfully encapsulated negatively charged gold nanoparticles and quantum dots into the SAPN. Such peptide-inorganic hybrid nanocomposites combine the optical properties of the inorganic nanoparticles and the biological functionality of the SAPN and hence may be useful for cell targeting and imaging applications.View Large Image | View Hi-Res Image | Download PowerPoint Slide
A definition of "on": patient diaries compared to the UPDRS.

Abstract This study investigates the relationship of the Unified Parkinson's Disease Rating Scale (UPDRS) to the patient's perception that they are “on”. Following the first dose of medication, patients reported that they were “on” when their UPDRS-III reached a mean of 8±2, representing a decrease of 67±8% from their early morning rating. Patients reported that they were “off” when their UPDRS-III score increased to 20±5, representing an increase of 50±12% from their initial “on” score. A 67% improvement in the baseline UPDRS-III score may be useful in defining “on”.
High reductase activity of recombinant NOS2 flavoprotein domain lacking the calmodulin binding regulatory sequence.

Abstract Nitric oxide synthases (NOSs) represent a special case of the cytochrome P450: cytochrome P450 reductase system in which the two redox partners occur as distinct domains on the same polypeptide chain and are linked by a calmodulin binding regulatory sequence. We expressed the carboxy-terminal, flavoprotein domain (residues 527–1144) of murine NOS2 in E. coli. The UV-visible spectrum of this domain resembles those of other flavoproteins, and the protein catalyses the reduction of ferricytochrome c by NADPH [Vmax= 3.1 ± .1 mol cytochrome reduced/minute/mmol flavoprotein domain, Km(cytochrome c) = 23 ± 2 μM, Km(NADPH) = 0.30 ± .06 μM]. The high reductase activity of this NOS2 flavoprotein domain, which lacks a calmodulin binding site, precludes a role for this site in mediating electron transfer within the flavoprotein domain of the intact enzyme. This is in contrast to the case of NOS1 and suggests that electron transfer is regulated differently in the two isoforms.
REASONS AND REASON REVISITED: ANOTHER REPLY TO MORRISON

In a previous article, Katherine Morrison (1999) argued that in my book Back to Reality: A Critique of Postmodern Theory in Psychotherapy (Held, 1995) I failed to accept the "strictly epistemological" aim of the narrative therapy movement. In the present article she reiterates the same objections, and adds the new criticism that I perceive epistemological oscillations in the writings of narrative therapists where there are none. In my present response I summarize my prior response to Morrison's (1999) critique (Held, 1999a), and I then respond to her new objections by showing how the conflation between epistemology and ontology that she attributes to me reflects her own confusion rather than mine.
Stress evolution during thermoset cure

The residual stress evolution in an epoxy during isothermal curing process has been determined experimentally. It was found that for a certain curing temperature range in which the characteristic time for the molecular motions leading to volume recovery is shorter than the time scale of the experiment, an incremental elastic constitutive equation can be used to describe the mechanical response of the epoxy. It was also found that appreciable residual stresses are developed in a threedimensionally constrained epoxy resin system within the rubbery state.
Urban Third Grade Teachers' Practices and Perceptions in Science Instruction with English Language Learners.

The study examined relationships among key domains of science instruction with English language learning (ELL) students based on teachers' perceptions of their classroom practices (i.e., what they think they do) and actual classroom practices (i.e., what they are observed doing). The four domains under investigation included: (1) teachers' knowledge of science content; (2) teaching practices to support scientific understanding; (3) teaching practices to support scientific inquiry; and (4) teaching practices to support English language development during science instruction. The study involved 38 third-grade teachers participating in the first-year implementation of a professional development intervention aimed at improving science and literacy achievement of ELL students in urban elementary schools. Based on teachers' self-reports, practices for understanding were related to practices for inquiry and practices for English language development. Based on classroom observations in the fall and spring, practices for understanding were related to practices for inquiry, practices for English language development, and teacher knowledge of science content. However, we found a weak to non-existent relationship between teachers' self-reports and observations of their practices.
Echinoderm Stabilization Associated with a Paleokarst Surface at the Mississippian-Pennsylvanian Boundary in Tennessee, U.S.A.

ABSTRACT Pennington Formation limestone deposits in Tennessee immediately underlie a paleokarst surface that straddles the Mississippian-Pennsylvanian unconformity. Vertic paleosols with significant gleying and coal seams overlie the paleokarst surface. This study quantifies the Fe loss associated with paleosol gleying and subsequent incorporation of Fe into echinoderm grains that underwent stabilization. Echinoderm grains immediately below the paleokarst surface have lower Mg and 13C values and higher Fe concentrations compared to echinoderm grains meters below the paleokarst surface. Additionally, echinoderm grains have variable 13C and invariant 18O values characteristic of alteration in a meteoric setting. Paleosols draping the paleokarst surface, and coal seams that were deposited immediately above the Mississippian-Pennsylvanian unconformity, provided ample organic matter that could have driven heterotrophic microbial activity. Additionally, the paleosols were an ample source of oxidized Fe that could have been used as a terminal electron acceptor by an anaerobic microbial community. Therefore, we suggest that Fe reduction transferred Fe from the paleosol to the limestone during meteoric stabilization of echinoderm grains. Fluid-rock modeling constrains the magnitude of Fe transfer that occurred during echinoderm stabilization. Stabilization can account for only a fraction (8 to 14%) of the total quantity of Fe lost from the gleyed paleosol, thus supporting the premise of continued transfer of Fe from the paleosol to limestone during burial diagenesis. Additionally, this study constrains the timescale associated with echinoderm stabilization, which was likely 12 ky. Finally, stabilization timescale is consistent with echinoderm alteration associated with organic diagenetic conditions, with elevated dissolved inorganic carbon in stabilizing pore fluids that were localized immediately below the paleokarst surface.
Disulfide bond stabilization of the hexameric capsomer of human immunodeficiency virus

Abstract The human immunodeficiency virus type 1 capsid is modeled as a fullerene cone that is composed of ∼ 250 hexamers and 12 pentamers of the viral CA protein. Structures of CA hexamers have been difficult to obtain because the hexamer-stabilizing interactions are inherently weak, and CA tends to spontaneously assemble into capsid-like particles. Here, we describe a two-step biochemical strategy to obtain soluble CA hexamers for crystallization. First, the hexamer was stabilized by engineering disulfide cross-links (either A14C/E45C or A42C/T54C) between the N-terminal domains of adjacent subunits. Second, the cross-linked hexamers were prevented from polymerizing further into hyperstable capsid-like structures by mutations (W184A and M185A) that interfered with dimeric association between the C-terminal domains that link adjacent hexamers. The structures of two different cross-linked CA hexamers were nearly identical, and we combined the non-mutated portions of the structures to generate an atomic resolution model for the native hexamer. This hybrid approach for structure determination should be applicable to other viral capsomers and protein–protein complexes in general.
Propagating two-dimensional magnetic droplets

Abstract Propagating, solitary magnetic wave solutions of the Landau–Lifshitz equation with uniaxial, easy-axis anisotropy in thin (two-dimensional) magnetic films are investigated. These localized, nontopological wave structures, parametrized by their precessional frequency and propagation speed, extend the stationary, coherently precessing “magnon droplet” to the moving frame, a non-trivial generalization due to the lack of Galilean invariance. Propagating droplets move on a spin wave background with a nonlinear droplet dispersion relation that yields a limited range of allowable droplet speeds and frequencies. An iterative numerical technique is used to compute the propagating droplet’s structure and properties. The results agree with previous asymptotic calculations in the weakly nonlinear regime. Furthermore, an analytical criterion for the droplet’s orbital stability is confirmed. Time-dependent numerical simulations further verify the propagating droplet’s robustness to perturbation when its frequency and speed lie within the allowable range.
VisualRank: Applying PageRank to Large-Scale Image Search

Because of the relative ease in understanding and processing text, commercial image-search systems often rely on techniques that are largely indistinguishable from text search. Recently, academic studies have demonstrated the effectiveness of employing image-based features to provide either alternative or additional signals to use in this process. However, it remains uncertain whether such techniques will generalize to a large number of popular Web queries and whether the potential improvement to search quality warrants the additional computational cost. In this work, we cast the image-ranking problem into the task of identifying "authority" nodes on an inferred visual similarity graph and propose VisualRank to analyze the visual link structures among images. The images found to be "authorities" are chosen as those that answer the image-queries well. To understand the performance of such an approach in a real system, we conducted a series of large-scale experiments based on the task of retrieving images for 2,000 of the most popular products queries. Our experimental results show significant improvement, in terms of user satisfaction and relevancy, in comparison to the most recent Google image search results. Maintaining modest computational cost is vital to ensuring that this procedure can be used in practice; we describe the techniques required to make this system practical for large-scale deployment in commercial search engines.
Enhanced low-light auto-focus system model in digital still and cell-phone cameras

In low-light conditions, the focus value curve or sharpness function that is used in passive auto-focusing becomes flat due to the increase in the noise level. This paper presents an enhanced low-light auto-focusing system model which provides performance improvements over our previously introduced low-light autofocusing model. This is achieved by utilizing an indexed family of focus value curves via a digital band-pass filterbank. A new sharpness ratio metric is presented for evaluation of auto-focusing in low-light conditions. Experimental results obtained from three different prototype camera platforms demonstrate the improved low-light performance over our previous model.
Effects of annealing electrodeposited bismuth telluride films

Thermoelectric thin films exhibit different qualities when compared with bulk materials. The goal however is to achieve thermoelectric properties of bulk materials from electrodeposited thin films. Thin films are produced by electrochemical deposition at room temperature. In order to optimize thermoelectric figure of merit proper carrier concentration must be obtained. The carrier concentration can be observed through resistivity measurements of thin film Bi/sub 2/Te/sub 3/ n-type depositions on thin chromium-gold substrates. Seebeck coefficient measurements are performed on Bi/sub 2/Te/sub 3/ n-type thin films deposited on molybdenum foil. Annealing samples in the presence of hydrogen argon forming gas increases thermopower and resistivity consistent with a decrease in carrier concentration. Annealing between 200 and 500 Celsius for 1 to 20 hours was tested. This produces films with resistivity of 1 m/spl Omega/cm but a Seebeck coefficient of only -60 /spl mu/V/K. Samples are suspected of remaining too heavily doped even after annealing. These results suggest there are defects in thin films that cannot be removed by annealing alone.
Thermal windows on Brazilian free-tailed bats facilitate thermoregulation during prolonged flight

The Brazilian free-tailed bat (Tadarida brasiliensis) experiences challenging thermal conditions while roosting in hot caves, flying during warm daylight conditions, and foraging at cool high altitudes. Using thermal infrared cameras, we identified hot spots along the flanks of free-ranging Brazilian free-tailed bats, ventral to the extended wings. These hot spots are absent in syntopic cave myotis (Myotis velifer), a species that forages over relatively short distances, and does not engage in long-distance migration. We hypothesized that the hot spots, or "radiators," on Brazilian free-tailed bats may be adaptations for migration, particularly in this long-distance, high-flying species. We examined the vasculature of radiators on Brazilian free-tailed bats with transillumination to characterize the unique arrangements of arteries and veins that are positioned perpendicular to the body in the proximal region of the wing. We hypothesized that these radiators aid in maintaining heat balance by flushing the uninsulated thermal window with warm blood, thereby dissipating heat while bats are flying under warm conditions, but shunting blood away and conserving heat when they are flying in cooler air at high altitudes. We also examined fluid-preserved specimens representing 122 species from 15 of 18 chiropteran families and radiators appeared present only in species in the family Molossidae, including both sedentary and migratory species and subspecies. Thus, the radiator appears to be a unique trait that may facilitate energy balance and water balance during sustained dispersal, foraging, and long-distance migration.
A crystal growth rate of equation for ancient dolomites; evidence for millimeter-scale flux-limited growth

ABSTRACT A linear correlation exists between the width of cathodoluminescent zones (CL) and the size of individual crystals in the Seroe Domi Fm (Miocene, Netherlands Antilles), Burlington-Keokuk Fm (Mississippian), Fort Payne Fm (Mississippian), and Saluda Fm (dovician). If individual zones, correlated by CL character and stratigraphy, are isochronous, then the width of a zone is directly proportional to the rate of crystal growth, Linear correlation coefficients for between-zone thickness and crystal size in individual thin sections range from 0.98 to 0.41, indicating a size dependence governing individual dolomite crystal growth rates. Mononuclear, polynuclear, spiral dislocation, and diffusion-limited crystal growth models operating under homogeneous or inhomogeneous kinetic conditions were considered as possible crystal growth mechanisms. Of the models considered, only mononuclear growth may result in a correlation between zone width and crystal radius in chemically homogeneous systems. However, this relationship is not linear. Any of the growth laws considered may produce a linear size-dependent growth rate when there are temporally constant differences between crystals in the kinetic factors governing growth. Differences in the kinetic factors governing growth could arise from stable variations in the chemistry of pore fluids related to permeability variations in the rock. The radius-rate data give a crystal growth rate equation of the form dr/dr = kr. This equation is consistent with a model wherein the rate of crystal growth is determined by stable variations in the chemistry of pore fluids. This implies that the kinetics of dolomite crystal growth is flux limited and therefore no slower than many diagenetic reactions. The data also support the hypothesis that thin-section-scale variations in dolomite crystal size can result from variations in crystal growth rate.
Curing Color Blindness—Mice and Nonhuman Primates

It has been possible to use viral-mediated gene therapy to transform dichromatic (red-green color-blind) primates to trichromatic. Even though the third cone type was added after the end of developmental critical periods, treated animals acquired red-green color vision. What happened in the treated animals may represent a recapitulation of the evolution of trichromacy, which seems to have evolved with the acquisition of a third cone type without the need for subsequent modification to the circuitry. Some transgenic mice in which a third cone type was added also acquired trichromacy. However, compared with treated primates, red-green color vision in mice is poor, indicating large differences between mice and monkeys in their ability to take advantage of the new input. These results have implications for understanding the limits and opportunities for using gene therapy to treat vision disorders caused by defects in cone function.
Trace HCN quantification using quartz enhanced photoacoustic spectroscopy

Detection of trace HCN concentrations in dry nitrogen and ambient air was performed by means of quartz enhanced photoacoustic spectroscopy using a near-infrared DFB laser source. A normalized detection sensitivity of 2.5middot10-9 cm-1 W/radicHz was achieved.
Emerging Roles for Ubiquitin and Protein Degradation in Neuronal Function

Alterations in cellular structure and synapse composition are central to proper nervous system function. Recent work has identified the ubiquitin-proteasome system (UPS) as a key regulator of neuronal biology. The UPS is essential for the growth and development of immature neurons and is a critical mediator of synaptic adaptability in mature neurons. Furthermore, proteinaceous deposits that accumulate in diverse neurodegenerative disorders are enriched in components of the UPS, suggesting that UPS dysfunction may be pivotal for pathogenesis. Here, we summarize existing knowledge about the role of the UPS in brain function, highlighting recent work delineating its importance in neuronal development, plasticity, and degeneration.
Exercise-Induced Left Ventricular Dysfunction in Symptomatic And Asymptomatic Patients With Aortic Regurgitation: Assessment With Radionuclide Cineangiography

Abstract In patients with aortic regurgitation, left ventricular dysfunction at rest, which is associated with a poor long-term prognosis, often develops before severe symptoms. To determine whether evidence of left ventricular dysfunction could be detected before if appeared at rest, 43 patients with severe aortic regurgitation were studied using radionuclide cineanglography during exercise. In 30 normal subjects, left ventricular ejection fraction increased during exercise (57 ± 1 percent [mean ± standard error] at rest, 71 ± 2 percent during exercise, P
Conceptualization of Sexual Orientation Identity Among Sexual Minorities: Patterns Across Sexual and Gender Identity

This research analyzed how sexual minority individuals discussed identity when critiquing two sexual orientation scales. To better understand the diversity of sexual minority experience, analyses focused on the patterns of responses across sexual orientation identity (monosexual, plurisexual, and asexual) and gender identity (cisgender and transgender). Participants were self-identified sexual minorities who represented a range of gender identities. Using thematic analysis, four main themes were identified related to sexual orientation identity: (1) salience of identity, (2) social identity, (3) identity development and change, and (4) identity and the body. Discussion focuses on understanding the findings in the context of intersectionality theory and emphasizes the need to conceptually disaggregate sexual orientation and gender identity. The conceptualization of sexual orientation as centered on normative assumptions of monosexuality, verisexuality/nonasexuality, genderism, and cisgenderism is also expl...
The CSC connects three major axonemal complexes involved in dynein regulation

Motile cilia and flagella are highly conserved organelles that play important roles in human health and development. We recently discovered a calmodulin- and spoke-associ­ated complex (CSC) that is required for wild-type motility and for the stable assembly of a subset of radial spokes. Using cryo–electron tomography, we present the first structure-based localization model of the CSC. Chlamydomonas flagella have two full-length radial spokes, RS1 and RS2, and a shorter RS3 homologue, the RS3 stand-in (RS3S). Using newly developed techniques for analyzing samples with structural heterogeneity, we demonstrate that the CSC connects three major axonemal complexes involved in dynein regulation: RS2, the nexin–dynein regulatory complex (N-DRC), and RS3S. These results provide insights into how signals from the radial spokes may be transmitted to the N-DRC and ultimately to the dynein motors. Our results also indicate that although structurally very similar, RS1 and RS2 likely serve different functions in regulating flagellar motility.
The Socio-Political Role of the Buraku (Hamlet) in Japan.

There presently exists in Japan an entire level of socio-political organization practically unknown to Westerners and little studied by the Japanese themselves until recent years. It comprises one of the lowest units of group organization in rural Japan and, in a practical everyday sense, plays a more immediate and important role in the daily lives of a larger proportion of the Japanese people than do any of the more formal and better known units of organization, such as the village, town, gun (county) or prefecture. This unit is known as the buraku, perhaps best rendered into English as hamlet.
Dissecting the Mystery Around Multiple Sclerosis

In patients with multiple sclerosis (MS), disseminated demyelination of brain and spinal cord neurons progressively produces neurologic deficits. The etiology of MS remains largely unknown; although existing therapies can achieve symptomatic relief, disease-modifying strategies have been
A technique for student program submission on UNIX systems

This paper presents a new scheme for collecting student programs and redistributing grades using simple UNIX scripts. Students keep their work in their own private subdirectories within a directory dedicated to a single class. When a program is due, control of the areas and files contained within them are passed over to the instructor. This locks the programs from alteration and provides a strict form of accountability. When the programs are graded, control of the area is returned to the individual student with the grade file both mailed to the student and left in a file readable by the student. Such a flexible framework has been used for a variety of languages and by students of varying levels of computing experience.
PSYCHOMETRIC VALIDITY OF PRORATION AND DIGIT SPAN SUBSTITUTION FOR ESTIMATING WISC-R VERBAL AND FULL SCALE IQS

This study investigated the merits of substituting the Digit Span subtest for an invalid Verbal Scale subtest versus a proration method in calculating WISC—R Verbal and Full Scale IQ. Subjects were...