cssi/SciSciGPT-SciSciNet huggingface dataset:
Landscapes for molecular evolution: Lessons from in vitro selection experiments with nucleic acids

The efficiency and complexity of natural biopolymers have long been a source of fascination to both biologists and chemists. Studies of molecular phylogeny have confirmed that the nanomachines of the cell are the products of evolution, just as earlier work in comparative physiology and zoology showed that macroscopic traits are under selective pressure. The understanding that molecules could evolve led inevitably to attempts to ‘breed’ better molecules, just as the understanding that genetics affected phenotype led to the startling diversity of dog, pigeon, and horse phenotypes originally commented on by Darwin. Starting with Spiegelman in the early 1970s [1], numerous researchers have carried out ‘test tube evolution’ experiments designed to produce novel molecular phenotypes.
Age-Predicted Maximal Heart Rate Equations Are Inaccurate for Use in Youth Male Soccer Players.

Purpose: The purpose of this study was to compare the differences between measured (MHRobt) and predicted (MHRpred) maximal heart rate (MHR) in youth athletes. Methods: In total, 30 male soccer players [14.6 (0.6) y] volunteered to participate in this study. MHRobt was determined via maximal-effort graded exercise test. Age-predicted MHR (MHRpred) was calculated for each participant using equations by Fox, Tanaka, Shargal, and Nikolaidis. Mean differences were compared using Friedman’s 2-way analysis of variance and post hoc pairwise comparisons. Agreement between MHRobt and MHRpred values was calculated using the Bland–Altman method. Results: There were no significant differences between MHRobt and MHRpred from the Fox (P = .777) and Nikolaidis (P = .037) equations. The Tanaka and Shargal equations significantly underestimated MHRobt (P < .001). All 4 equations produced 95% limits of agreement of ±15.0 beats per minute around the constant error. Conclusions: The results show that the Fox and Nikolaidis e...
Author Correction: Inflammatory memory sensitizes skin epithelial stem cells to tissue damage.

In Fig. 2g of this Article, a panel was inadvertently duplicated. The ‘D30 IMQ’ image was a duplicate of the ‘D6 Ctrl’ image. Fig. 2g has been corrected online to show the correct ‘D30 IMQ’ image (showing skin inflammation induced by the NALP3 agonist imiquimod, IMQ). The Supplementary Information to this Amendment contains the old, incorrect Fig. 2 for transparency.
Movement through space and spatially organized behavior

A renewed interest in the concept of cognitive maps (Tolman, 1948) has been stimulated by recent behavioral and neuropsychological research (Stahl & Ellen, 1973, 1974; O’Keefe & Nadel, 1978). Of particular interest is the question of how cognitive spatial maps are acquired (Olton, 1977). The literature suggests that movement through space is crucial for efficient performance by organisms on spatial tasks which require the establishment of an hypothesized “cognitive map,” or “orienting schema” (Neisser, 1976). Our research with the Maier 3-table spatial problem demonstrated that exploration of the entire apparatus was necessary for rats to solve the problem (Stahl & Ellen, 1974). Exploration of only portions of the apparatus is not sufficient (Ellen, Soteres & Wages, 1984). A clarification of the role of movement and exploration in spatially organized behavior would advance significantly our understanding of cognitive processes. Thus, the experiments reported here were designed to determine whether active exploration or merely passive movement through space is necessary for solving the Maier 3-table spatial problem.
IP6-induced growth inhibition and differentiation of HT-29 human colon cancer cells : Involvement of intracellular inositol phosphates

Inositol hexaphosphate (InsP6 or IP6) ubiquitous in plants and animals is not only a natural antioxidant, but may also be the precursor/storage of intracellular inositol phosphates, important for various cellular functions. A novel anti-tumor action of InsP6 was demonstrated in models of experimental colon and mammary carcinogenesis in vivo. We now show its effects on growth and differentiation of HT-29 human colon carcinoma cells in vitro. A dose- and time-dependent (0.33-20 mM InsP6 and 1-6 days treatment) growth inhibition was observed as tested by MTT- incorporation assay. The inhibition was statistically significant (p < 0.05) at 1 mM concentration as early as first day after treatment and continued up to 6 days. DNA-synthesis was also suppressed by InsP6 and significantly inhibited as early as 6 h after treatment at 1 mM concentration (p < 0.05) and continued to 48 h (p < 0.01). The expression of proliferation marker PCNA was down-regulated (p < 0.05) by InsP6 (1 and 5 mM) after 48 h of treatment. To investigate the mechanism of action of InsP6 the intracellular phosphatases (including phytase) were inhibited by F to slow down the dephosphorylation of InsP6. Ion-exchange chromatographic separation of intracellular inositol phosphates demonstrated a 84-98% decrease of Ins, InsP1 and InsP2 InsP3 was reduced by 39% and InsP4 and InsP5 by 21% and 13% respectively, whereas intracellular InsP6 was increased by 24.6% at 5 min following 3H-InsP6. Since neither the rate of uptake of 3H-InsP6 was unaffected, nor was the efficacy of growth inhibition altered by F inhibition of phytase, data suggest that contrary to the popular misconception, phytase plays no role in influencing the anti-neoplastic action of InsP6. Alkaline phosphatase activity (brush border enzyme, associated with absorptive cell differentiation), increased following 1 and 5 mM InsP6 treatment for 1-6 days. The expression of a mucin antigen associated with goblet cell differentiation and defined by the monoclonal antibody CMU10 was augmented (p < 0.0001) by InsP6. The tumor mucin marker Gal-GalNAc, expressed by precancer and cancer of colon, but not by the normal cells showed a time-dependent biphasic change by InsP6; an increased expression after 1 day of treatment followed by suppression after 2 days suggest progression of mucin synthesis and differentiation of cancer cells with reversion to normal phenotype. Because the tumor marker Gal-GalNAc is a) easily detected in rectal mucin of patients with colonic cancer and precancer with high sensitivity and specificity, and b) suppressed by InsP6 treatment, it can be used to monitor the efficacy of chemoprevention by InsP6 or other such agents. Since InsP6 a natural dietary ingredient of cereals and legumes, inhibits growth and induces terminal differentiation of HT-29 cancer cells, it is an excellent candidate for adjuvant chemotherapy and prevention of cancer.
Novel neurotransmitters for sleep and energy homeostasis.

We have developed methodologies for identifying mRNAs with highly restricted expression within the brain. One postnatal-onset mRNA, restricted to sparse GABAergic interneurons of the cerebral cortex and hippocampus, encodes preprocortistatin, the precursor of a 14-residue peptide that shares 11 amino acids with somatostatin. Cortistatin binds to all five cloned somatostatin receptors when they are expressed in transfected cells and depresses neuronal activity, but, unlike somatostatin, it reduces locomotor activity and induces slow-wave sleep. Cortistatin, whose mRNA accumulates during sleep deprivation, apparently acts by antagonizing the effects of acetylcholine on cortical excitability, thereby causing synchronization brain slow waves. A single amino acid difference with somatostatin accounts for the dramatic differences in the effects of the two peptides on physiology and behavior.
Photostimulated tert-butylations of a,b-unsaturated nitriles, cyclizations of 1,6-dienes and olefinic nitriles, and homolytic aromatic alkylations

a,P-Unsaturated nitriles undergo radical chain addition reactions with tertbutylmercury halides in the presence of iodide ions. The mercury adduct products are formed in high yields and can be converted to the reductive alkylation products with NPU"'" or by NaBfit. The addition reaction involves the attack of the adduct radical upon the ate complex, r-BuHgl2'. Proton donors also promote the reactions by protonating the adduct radicals to form keteniminyl radicals cations which accept an electron from f-BuHgl2" to produce the alkylation products. Acrylonitrile, crotononitrile and fumaronitrile give nearly quantitative yields of the products in DMSO via photolysis or even in the dark at room temperature. Three-component condensation reactions occur for mixtures of acrylonitrile/fBuHgl and reagents such as CH2=CHCH2Br or CH2=CHCH2SPh or upon further reaction of the mercury adducts with I2, NBS, PhCH=CHI, PhSeSePh, or iminium ions. Cyclization reactions of 1,6-dienes with f-BuHgX have been investigated. A radical chain process provides the cyclized organomercurials via 5-exo mode cyclization. Cis and trans isomeric cyclized mercury compounds are obtained with the cw-isomers preferred. The measured initial kinetic chain length for the substrates are 3-10. Photolysis of the mercury compounds with PhSSPh leads to the corresponding sulfides. Allyl vinylphosphonates react with r-BuHgX very readily. However, the cis/trans product ratio is 1:1. Alkylmercury halides are very suitable reagents for alkylation of electron-deficient aromatics. In the presence of Dabco (l,4-diazabicycIo[2.2.2]octane), the disubstituted benzenes undergo a regioselective radical alkylation reaction. For 1,3-dicyanobenzene, the initial kinetic chain length is 22 and not only the mono-alkylated but also the dialkylated product is produced in high yield. With larger groups meta or para to a cyano group such as -CHO and -C02Et, the second alkylation is inhibited. Dabco promotes the chain reaction by removing a proton from adduct cyclohexadienyl radical. The radical anion formed is oxidized by r-BuHgX to afford the product and regenerate f-Bu*.
Knots and tangles weaken kelp fronds while increasing drag forces and epifauna on the kelp

Abstract In shallow coastal areas, the fronds of long, flexible kelp can become knotted (a single frond tied around itself) and tangled (multiple fronds intertwined) as they move back and forth with ocean waves. We investigated the ecological and physical consequence of being knotted and tangled for the intertidal kelp Egregia menziesii in northern California. Knots increased the hydrodynamic forces on fronds of the kelp Egregia menziesii by 56% and weakened fronds by 18% when pulled in tension. There were more and larger epifauna (including many herbivores) on tangled fronds, which suffered greater damage by grazers than did untangled fronds. Tensile forces required to break herbivore-damaged fronds were 31% lower than forces to break undamaged fronds. Kelp with knotted and tangled fronds were more likely to break than kelp with unknotted, untangled fronds, and knots and tangles occurred most frequently in the autumn, thereby pruning the fronds and reducing the risk of whole kelp being ripped off the shore by large waves during winter storms.
The effects of collector geometry on the internal structure of the 3D nanofiber scaffold fabricated by divergent electrospinning

Latest bioinspired approaches in tissue engineering focus on the creation of biomaterials with micro- and nanoscale topographical features. Various additive manufacturing techniques have been applied for scaffold fabrication; however, creating three dimensional (3D) nanofiber structure within a scaffold remains to be challenging. This paper presented an innovative divergence electrospinning strategy to fabricate 3D polycaprolactone (PCL) scaffolds comprised of uniaxially aligned nanofibers. The effects of collector geometry on the nanofiber structure were characterized by polynomial regression analysis. The length-to-width ratio and inclination angle of the collector were found to be critical to nanofiber distribution within the 3D scaffold. The nanofiber orientation was consistent with the direction of electric field vectors between the two bevels of the collector. After a continuous culturing for 7 days, fibroblast cells were uniaxially organized within the 3D scaffolds, closely resembling the fibrous structure in musculoskeletal tissues. This study provided a novel approach to biomimetic native tissue microstructures and showed a great potential as a future fabrication additive manufacturing platform for tissue engineering.
Branched Short-Chain Fatty Acid Isovaleric Acid Causes Colonic Smooth Muscle Relaxation via cAMP/PKA Pathway

Isovaleric acid (IVA) is a 5-carbon branched-chain fatty acid present in fermented foods and produced in the colon by bacterial fermentation of leucine. We previously reported that the shorter, straight-chain fatty acids acetate, propionate and butyrate differentially affect colonic motility; however, the effect of branched-chain fatty acids on gut smooth muscle and motility is unknown. To determine the effect of IVA on contractility of colonic smooth muscle. Murine colonic segments were placed in a longitudinal orientation in organ baths in Krebs buffer and fastened to force transducers. Segments were contracted with acetylcholine (ACh), and the effects of IVA on ACh-induced contraction were measured in the absence and presence of tetrodotoxin (TTx) or inhibitors of nitric oxide synthase [L-N-nitroarginine (L-NNA)] or adenylate cyclase (SQ22536). The effect of IVA on ACh-induced contraction was also measured in isolated muscle cells in the presence or absence of SQ22536 or protein kinase A (PKA) inhibitor (H-89). Direct activation of PKA was measured in isolated muscle cells. In colonic segments, ACh-induced contraction was inhibited by IVA in a concentration-dependent fashion; the IVA response was not affected by TTx or L-NNA but inhibited by SQ22536. Similarly, in isolated colonic muscle cells, ACh-induced contraction was inhibited by IVA in a concentration-dependent fashion and the effect blocked by SQ22536 and H-89. IVA also increased PKA activity in isolated smooth muscle cells. The branched-chain fatty acid IVA acts directly on colonic smooth muscle and causes muscle relaxation via the PKA pathway.
Pancreatic exocrine function. Comparison of responses to augmented secretin stimulus, augmented pancreozymin stimulus, and test meal in health and disease.

The relative value of certain tests of pancreatic exocrine function was assessed by the sequential administration of (1) an augmented dose of secretin, (2) an augmented dose of pancreozymin, and (3) a test meal. Eighty-one individuals were studied—namely, the control group of 47 persons (24 healthy volunteers and 23 patients with nonpancreatic disease) and a group of 34 patients with pancreatic disease. The latter group included 17 patients with chronic pancreatitis: 2 with subacute relapsing pancreatitis and 15 with carcinoma of the pancreas. Measurements of volume, bicarbonate output (peak and total), and bicarbonate concentration (maximal and 60-min.) were made with and without reference to body weight, after administration of secretin. Concentrations and outputs of trypsin and amylase were measured after the administration of pancreozymin and the test meal. The augmented secretin test yielded the most reliable results, both in indicating pancreatic disease and in differentiating between chronic pancreatitis and pancreatic carcinoma; measurements of volume output per kilogram of body weight, peak or total bicarbonate output, and maximal bicarbonate concentration were the most appropriate data for these purposes. Satisfactory, but less reliable, results were those of secretion that followed the administration of an augmented dose of pancreozymin or a test meal; the findings after these two tests were comparable. Mayo Clinic Rochester, Minn. 55902
Abstract 159: Improving Chronic Motor and Cognitive Recovery After Stroke Using Injury-site Specific Inhibition of Complement Activation

Introduction: After stroke, penumbral cells express neoepitopes that are recognized by natural IgM antibodies (NIgM) leading to complement (C) activation and propagation of inflammation. We previou...
Influence of Surface Ligands on Energetics at FASnI3/C60 Interfaces and Their Impact on Photovoltaic Performance

Interfacial chemistry and energetics significantly impact the performance of photovoltaic devices. In the case of Pb-containing organic metal halide perovskites, photoelectron spectroscopy has been...
Structural preferences of cysteine sulfinic acid: The sulfinate engages in multiple local interactions with the peptide backbone

Abstract Cysteine sulfinic acid (Cys-SO2–) is a non-enzymatic oxidative post-translational modification (PTM) that has been identified in hundreds of proteins. However, the effects of cysteine sulfination are in most cases poorly understood. Cys-SO2– is structurally distinctive, with long sulfur-carbon and sulfur-oxygen bonds, and with tetrahedral geometry around sulfur due to its lone pair. Cys-SO2– thus has a unique range of potential interactions with the protein backbone which could facilitate protein structural changes. Herein, the structural effects of cysteine oxidation to the sulfinic acid were investigated in model peptides and folded proteins using NMR spectroscopy, circular dichroism, bioinformatics, and computational studies. In the PDB, Cys-SO2– shows a greater preference for α-helix than Cys. In addition, Cys-SO2– is more commonly found in structures with ϕ > 0, including in multiple types of β-turn. Sulfinate oxygens engage in hydrogen bonds with adjacent (i or i + 1) amide hydrogens. Over half of sulfinates have at least one hydrogen bond with an adjacent amide, and several structures have hydrogen bonds with both adjacent amides. Alternately, sulfur or either oxygen can act as an electron donor for n→π* interactions with the backbone carbonyl of the same residue, as indicated by frequent S⋯C =O or O⋯C =O distances below the sums of their van der Waals radii in protein structures. In peptides, Cys-SO2– favored α-helical structure at the N-terminus, consistent with helix dipole effects and backbone hydrogen bonds with the sulfinate promoting α-helix. Cys-SO2– has only modestly greater polyproline II helix propensity than Cys-SH, likely due to competition from multiple side chain-backbone interactions. Cys-SO2– stabilizes the i+1 position of a β-turn relative to Cys-SH. Within proteins, the range of side chain-main chain interactions available to Cys-SO2– compared to Cys-SH provides a basis for potential changes in protein structure and function due to cysteine oxidation to the sulfinic acid.
Special unitary particle pusher for extreme fields

Abstract An exact momentum update useful for particle codes was previously given. The expressions involved were unwieldy. By treating the momentum as a representation of SU(2) ⊗ SU(2) instead of SO(3,1), a more compact expression for the exact momentum update is obtained. An expansion in powers of the timestep can be formulated such that invariance properties are exactly preserved, and push rates comparable to the standard Boris pusher are obtained.
Depression and Anxiety Subgroups Across Alcohol Use Disorder and Substance Use in a National Epidemiologic Study.

Objective: The high prevalence of alcohol/substance use among individuals with psychiatric disorders elucidates the import of investigations into associations between types and severity of psychiat...
Bayesian Modeling for Simultaneous Regression and Record Linkage

Often data analysts use probabilistic record linkage techniques to match records across two data sets. Such matching can be the primary goal, or it can be a necessary step to analyze relationships among the variables in the data sets. We propose a Bayesian hierarchical model that allows data analysts to perform simultaneous linear regression and probabilistic record linkage. This allows analysts to leverage relationships among the variables to improve linkage quality. Further, it enables analysts to propagate uncertainty in a principled way, while also potentially offering more accurate estimates of regression parameters compared to approaches that use a two-step process, i.e., link the records first, then estimate the linear regression on the linked data. We propose and evaluate three Markov chain Monte Carlo algorithms for implementing the Bayesian model, which we compare against a two-step process.
A high fat anti-inflammatory diet improves widespread allodynia despite worsening metabolic outcomes in adult mice exposed to neonatal maternal separation

Inflammation plays a key role in the progression and maintenance of chronic pain, which impacts the lives of millions of Americans. Despite growing evidence that chronic pain can be improved by treating underlying inflammation, successful treatments are lacking and pharmaceutical interventions are limited due to drug side effects. Here we are testing whether an anti-inflammatory diet (AID) containing a combination of key anti-inflammatory compounds, at clinically relevant doses, improves pain-like behaviors in a preclinical model of chronic widespread hypersensitivity induced by neonatal maternal separation (NMS). Our results demonstrate a benefit of the AID on pain-like behaviors, despite the diet being high in fat, which led to increased caloric intake, adiposity, and weight gain. The AID specifically increased measures of metabolic syndrome and inflammation in female mice, compared to an isocaloric, macronutrient-matched diet lacking the anti-inflammatory compounds. Male mice, especially those exposed to NMS, were equally susceptible to both diets worsening metabolic measures. This work highlights important sexual dimorphic outcomes related to early life stress exposure and dietary interventions, as well as a potential disconnect between improvements in pain-like behaviors and metabolic measures.
Vaccine hesitancy and reasons for refusing the COVID-19 vaccination among the U.S. public: A cross-sectional survey

ImportanceAlthough widespread vaccination will be the most important cornerstone of the public health response to the COVID-19 pandemic, a critical question remains as to how much of the United States population will accept it. ObjectiveDetermine: 1) rate of COVID-19 vaccine hesitancy in the United States public, 2) patient characteristics associated with hesitancy, 3) reasons for hesitancy, 4) healthcare sites where vaccine acceptors would prefer to be vaccinated. Design43-question cross-sectional survey conducted November 17-18, 2020, distributed on Amazon Mechanical Turk, an online labor marketplace where individuals receive a nominal fee (here, $1.80) for anonymously completing tasks. Eligible ParticipantsUnited States residents 18-88 years of age, excluding healthcare workers. A total 1,756 volunteer respondents completed the survey (median age 38 years, 53% female). Main Outcome MeasureMultivariable logistic regression modeled the primary outcome of COVID-19 vaccine hesitancy (defined as non-acceptance or being unsure about acceptance of the COVID-19 vaccine) with respondent characteristics. ResultsA total 663 respondents (37.8%) were COVID-19 vaccine hesitant (374 [21.3%] non-acceptors and 289 [16.5%] unsure about accepting). Vaccine hesitancy was associated with not receiving influenza vaccination in the past 5 years (odds ratio [OR] 4.07, 95% confidence interval [CI] 3.26-5.07, p<0.01), female gender (OR 2.12, 95%CI 1.70-2.65, p<0.01), Black race (OR 1.54, 95%CI 1.05-2.26, p=0.03), having a high school education or less (OR 1.46, 95%CI 1.03-2.07, p=0.03), and Republican party affiliation (OR 2.41, 95%CI 1.88-3.10, p<0.01). Primary reasons for hesitancy were concerns about side effects, need for more information, and doubts about vaccine efficacy. Preferred sites for vaccination for acceptors were primary doctors offices/clinics, pharmacies, and dedicated vaccination locations. ConclusionsIn this recent national survey, over one-third of respondents were COVID-19 vaccine hesitant. To increase vaccine acceptance, public health interventions should target vaccine hesitant populations with messaging that addresses their concerns about safety and efficacy.
Multi-functional cerium oxide nanoparticles regulate inflammation and enhance osteogenesis.

Abstract Oxidative stress increases bone loss and limits repair, in part, through immunoregulation and the formation and maintenance of low-grade chronic inflammation. The aim of this study was to investigate the effect of cerium oxide nanoparticles (CeONPs) on (i) macrophage phenotype and cytokine expression under normal and simulated acute and chronic inflammatory conditions and, (ii) human mesenchymal stem cell (hBMSCs) proliferation, osteoinduction and osteogenic differentiation. Spherical particles composed of 60% Ce3+ with a hydrodynamic size of ~35 nm and surface charge of 25.4 mV were internalized within cells. Under both acute and chronic conditions, inducible nitric oxide synthase (iNOS) activity decreased with a significant reduction seen in the 1 and 10 μg/mL groups (p
Homenagem: Remembering the Life and Work of Abdias Nascimento:

This essay provides a brief introduction to this special issue focused on the life and work of Black Brazilian scholar-activist Abdias Nascimento. The contributors include, Vera Lucia Benedito, Oll...
Effects of tACS-Like Electrical Stimulation on On-Center Retinal Ganglion Cells: Part I.

Purpose Electrical stimulation of the human central nervous system via surface electrodes has been used for both learning enhancement and the amelioration of neurodegenerative or psychiatric disorders. However, data are sparse on how such electrical stimulation affects neural circuits at the cellular level. This study assessed the effects of tACS-like currents at 10 Hz on On-center retinal ganglion cell responsiveness, using the rabbit retina eyecup preparation as a model for central nervous system effects. Methods We made extracellular recordings of light-evoked spike responses in different classes of On-center retinal ganglion cells before, during and after brief applications of 1 microampere alternating currents using single electrodes and microelectrode arrays. Results tACS-like currents (tACS) of 1 microampere produced effects on On-center ganglion cell response profiles immediately after initiation or cessation of tACS, without driving phase-locked firing in the absence of light stimuli. tACS affected the initial transient responses to light stimulation for all cells, sustained response components (if any) more strongly for sustained cells, and the center-surround balance more strongly for transient cells. Conclusion tACS sculpted light-evoked responses that lasted for one or more hours after cessation of current without, itself, directly inducing significant firing changes. Functionally, tACS effects could result in effects on contrast thresholds for both broad classes of cells, but because tACs differentially affects the center-surround balance of transient On-center cells, there may be greater effects on the spatial resolution and gain. The isolated retina appears to be a useful model to understand tACS actions at the neuronal level.
Finding surfaces in simplicial complexes with bounded-treewidth 1-skeleton.

We consider the problem 2-Dim-Bounding-Surface. 2-Dim-Bounded-Surface asks whether or not there is a subcomplex $S$ of a simplicial complex $K$ homeomorphic to a given compact, connected surface bounded by a given subcomplex $B\subset K$. 2-Dim-Bounding-Surface is NP-hard. We show it is fixed-parameter tractable with respect to the treewidth of the 1-skeleton of the simplicial complex $K$. Using some of the techniques we developed for the 2-Dim-Bounded-Surface problem, we obtain fixed parameter tractable algorithms for other topological problems such as computing an optimal chain with a given boundary and computing an optimal chain in a given homology class.
Introduction to Sport Biomechanics

The science of biomechanics within the field of sport and physical education has developed rapidly during the past decade. Central to this progress has been the development of sophisticated research and instrumentation systems. Research activities have focused on fundamental laboratory experiments and applied projects occurring in the sports environment. Fundamental studies utilize on-line computer techniques which provide accurate and rapid processing and analysis of large quantities of data derived from a variety of measurement systems. High speed motion photography and automated film analysis constitute the primary method in applied sport studies.
Augmenting domain theory for explanation-based generalisation

Publisher Summary This chapter addresses one of the shortcomings of explanation-based generalization (EBG), namely, that EBG requires the domain theory to be complete. EBG is a form of learning that uses a strong domain theory to constrain the search for generalizations of the concept that is being learned. EBG attempts to explain why the example is a positive instance of the target concept. As the domain theory already has general rules for proving the concept, the benefit of the method is its ability to operationalize and generalize the explanation. The system is capable of learning disjunctive structured concepts one disjunct at a time. It can acquire new rules and missing disjuncts, and cope with an expanding instance language. It also forms operationalized definitions of the concept to improve performance. It learns best when several concepts with shared subconcepts are learned simultaneously. Disadvantages of this approach comprise an inability to learn intermediate concepts and missing conjuncts. It also forms overly specific rules in contexts where one conjunct is invariant. The system is not discriminating enough when linking predicates to find new rules. Some form of background knowledge as in OCCAM (Pazzani, 1988) would be useful. An ability to detect and retract erroneous rules would also be useful. More discriminating forms of generalization would also allow learning of more complicated concepts.
Publishing Perils in Academe: The Serials Crisis and the Economics of the Academic Journal Publishing Industry

Abstract The continual escalation in academic journal prices threatens the quality and future of academic library collections. This situation arises from market forces that react to, and take advantage of, the unique characteristics of academic libraries and scholarly publishing. These characteristics include the unique role of academic libraries, in their mission of serving as accessible repositories of knowledge, and the unique activity of scholarly publishing, in which every journal title is unique without a close substitute. The combination of these of factors leads to the lowest price elasticity of demand for the libraries and the highest degree of product differentiation for each journal title. While some solutions being offered to alter the dilemma hold promise, the unique characteristics of the market appear to discourage more equitable pricing without a radical restructuring of the industry or of the relationships between the consumers and the producers of academic journals.
Mannosyl Transfer by Membranes of Aspergillus niger: Mannosylation of Endogenous Acceptors and Partial Analysis of the Products

A smooth membrane fraction of Aspergillus niger catalyzed the transfer of mannose from GDP-mannose to endogenous lipid and protein acceptors. The mannolipid was acidic, as judged by diethylaminoethyl-cellulose chromatography, and had a mobility similar to ficaprenyl phosphate on thin-layer chromatograms. Mannose transfer occurred optimally at pH 6.5 to 7.5 and required Mn 2+ for use of the protein as acceptor, but either Mn 2+ or Mg 2+ with the lipid as acceptor. Glycopeptides of the mannosylated protein ([ 14 C]gly) and of an α-glucosidase (α-glu) secreted by the organism were produced by Pronase digestion and separation of the products on Sephadex G-25. Because ovalbumin has a carbohydrate composition similar to that of α-glu and because the carbohydrate structure of ovalbumin is known, ovalbumin glycopeptides (Ov) were similarly obtained and used as standards in determining carbohydrate structures. Oligosaccharide chains of [ 14 C]gly, α-glu, and Ov were obtained by treatment of the respective glycopeptides with endo-β- N -acetylglucosaminidase, reduction with NaBT 4 , and concanavalin A-Sepharose chromatography. The 3 H-labeled oligosaccharides obtained were subjected to the following treatments: (i) digestion with α- and β-mannosidases, (ii) Smith degradation, and (iii) acetolysis. Subsequently, changes in paper chromatographic mobilities were detected. Also, α-glu was permethylated, and the partially methylated alditol acetates were analyzed by gas-liquid chromatography. The resultant proposed structure shows that the oligosaccharide chain of α-glu is almost identical to that of an Ov chain, while [ 14 C]gly has a structure which is probably the same as that of α-glu. It is suggested that the transferase(s) involved in [ 14 C]gly synthesis in vitro may be responsible for glycosylation of secreted enzymes.
Interactions of normal and mutant vesicular stomatitis virus matrix proteins with the plasma membrane and nucleocapsids.

Abstract We demonstrated recently that a fraction of the matrix (M) protein of vesicular stomatitis virus (VSV) binds tightly to cellular membranes in vivo when expressed in the absence of other VSV proteins. This membrane-associated M protein was functional in binding purified VSV nucleocapsids in vitro. Here we show that the membrane-associated M protein is largely associated with a membrane fraction having the density of plasma membranes, indicating membrane specificity in the binding. In addition, we analyzed truncated forms of M protein to identify regions responsible for membrane association and nucleocapsid binding. Truncated M protein lacking the amino-terminal basic domain still associated with cellular membranes, although not as tightly as wild-type M protein, and could not bind nucleocapsids. In contrast, deletion of the carboxy-terminal 14 amino acids did not disrupt stable membrane association or nucleocapsid interaction. These results suggest that the amino terminus of M protein either interacts directly with membranes and nucleocapsids or stabilizes a conformation that is required for M protein to mediate both of these interactions.
Is There a J-Curve for the Economic Transition from Socialism to Capitalism?

Much economic thinking about current developments in Eastern Europe, where the transition from plan to market and from socialism to capitalism is underway, seems to show, once again, that economics is, indeed, the dismal science. Specifically, both western observers and policymakers in these countries appear to believe that there is some sort of large and negative supply-side shock that this transition imparts to the reforming economies. For lack of a more pejorative term, we will call this J-curve pessimism. Such J-curve pessimism does not appear to dominate other aspects of life. People who undertake diets or begin to exercise, for example, can correctly expect that this course of action will lead them to lose weight or become fitter in a way that is directly related to the rigor of their diet or exercise regime. It is only the dismal science of economics that would have them believe that their efforts would first lead to gains in weight or worsened fitness, and only in the distant future to an improved state of health.
Stochastic one-body transport and coherent collision term

The stochastic one-body transport theory in non-relativistic framework is briefly reviewed, and a coherent damping mechanism arising from the coupling between the mean-field fluctuations and the single-particle motion is discussed. For small amplitude fluctuations, the coherent mechanism appears as a particle-phonon collision term in the transport equation for the average density matrix, which play a dominant role in damping of giant resonance excitations and nuclear collective motion at low energies.
Battle over CCL2 for control of the metastatic niche: neutrophils versus monocytes

Tumor-derived factors, such as proinflammatory cytokines, can increase the hospitality of metastatic sites by recruiting and activating leukocytes to perform supporting roles during metastatic dissemination. These same cytokines, however, are natural danger signals for the immune system and as such can induce anti-tumor immune responses by both adaptive and innate immune cells. The outcome of tumor-derived inflammatory cytokines is probably closely related to the exact repertoire of factors produced by each tumor. Several recent studies have investigated these seemingly contradictory roles of tumor-derived CCL2 with significant clinical implications.
Citizenship and Education in the Homework Completion Routine

This article draws from a 23-month ethnographic study of mixed-status Mexican families living in the New Latino Diaspora to examine how citizenship status impacts undocumented parents' and children's participation in everyday activities. Specifically, the analysis illustrates how mothers and sons in two families negotiate school and home definitions of citizenship during Homework Completion Routines. During this recurrent educational activity, family members socialized one another to identities that were inextricably linked to migratory status. [language socialization, citizenship, participation, homework, report cards]
Optimal equivariant estimator with respect to convex loss function

Abstract Consider a family of probability distributions which is invariant under a group of transformations. In this paper, we define an optimality criterion with respect to an arbitrary convex loss function and we prove a characterization theorem for an equivariant estimator to be optimal. We illustrate this theorem under some conditions on convex loss function.
High speed low noise multiplexed three color absorbance photometry

Multispectral photometry is often required to distinguish samples in flow injection analysis and flow cytometry; however, the cost of multiple light detectors, filters, and optical paths contribute to the high cost of multicolor and spectral detection systems. This paper describes frequency division multiplexing (FDM), a simple approach for performing multi-wavelength absorbance photometry with a single light detector and a single interrogation window. In previous efforts, modulation frequencies were <10 KHz, resulting in a detector bandwidth of <20 Hz. This paper presents a high frequency FDM circuit which can increase the oscillation frequencies to several 100 KHz, improving the detection bandwidth by a factor of 10 while still maintaining low cost. Light from 3 different LED sources are encoded into unique frequency channels, passed through the detection cell, and later demodulated using phase-sensitive electronics. Electronic multiplexing couples all light sources into a single optical train without spectral filters. Theory and high frequency considerations are demonstrated. Simultaneous three color absorbance detection is demonstrated in solutions and in flowing droplet microreactors. This technique can potentially reduce the cost of multicolor photometry by replacing expensive optical components with low-cost electronics.
Management of narcolepsy.

Background: Narcolepsy is a rare chronic sleep disorder classically characterized by excessive daytime sleepiness. Other symptoms of the disease, including cataplexy, sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep, may follow later. The disease can be incapacitating and frequently results in impaired psychosocial interaction. In the absence of a cure for narcolepsy, medical therapy is directed at symptom control. Objectives: The aim of this study was to review the current approach to the treatment of narcolepsy. Methods: A search of three bibliographic databases (MEDLINE/PubMed, EMBASE and the Cochrane Library Database) was conducted from 1966 to January 2008 using the National Library of Medicine MeSH search terms narcolepsy and cataplexy. Relevant studies, case reports, review articles, editorials, short communications and chapters from selected textbooks were then extracted and manually cross-referenced. Results/conclusions: Traditionally, stimulants have been used to improve ...
Zeroth-order effective medium theory of zeroth-order volume gratings

Zeroth-order effective medium theory is applied to analyze the properties of volume holographic gratings that have periods much smaller than the illumination wavelength. These holograms, called zeroth order gratings, can be modeled as negative uniaxial films using the quasistatic field approximation. Exact analytic expressions for the form birefringence of gratings with sinusoidal, rectangular, and triangular permittivity profiles are obtained and compared. Approximate equations are derived that indicate a quadratic dependence of the form birefringences on the permittivity modulation. It is determined that the optimum rectangular profile yields the greatest form birefringence.
Fatigue life estimation for ITER CS conductor jacket by probabilistic fracture mechanics

The conductor jacket of the ITER central solenoid (CS) will experience a cyclic tension load due to the electromagnetic forces during operation. The jacket is designed to sustain at least 60,000 full stress cycles. Probabilistic fracture mechanics (PFM) has been applied to estimate the fatigue life of the jacket. The PFM analysis covers almost all independent variables and the correlation among them. It includes Monte Carlo simulation, small sample statistics, and uncertainty analysis. As the basis of PFM, the defects in welds are first discussed, a 3D defect model is developed, deterministic fracture mechanics is reviewed, and a method to estimate the fatigue initiation life is proposed. The results of PFM analysis on the CS conductor jacket made of the alloy JK2LB show that the relationship between the reliability in the high end and the total fatigue life follows a Weibull distribution.
A second polycaprolactone depolymerase from Fusarium, a lipase distinct from cutinase

Polycaprolactone (PCL), a synthetic polyester with applications in biodegradable plastics, is degraded by a variety of microorganisms, including fungal phytopathogens. These pathogens secrete cutinase, which hydrolyzes cutin, the polyester structural component of plant cuticle, releasing ω-hydroxy fatty acids that induce cutinase synthesis. Our laboratory previously reported that growth of Fusarium solani on PCL requires cutinase, which is active as a PCL depolymerase and induced by the products of its action on PCL. A mutant strain of F. solani in which the cutinase gene is deleted was unable to grow on PCL and did not secrete PCL depolymerase activity in the media tested. It is now shown that this mutant produces a PCL depolymerase in media containing lipase inducers. Wild-type strains also produce this second PCL depolymerase, which is induced by Tween 80 and tributyrin, but not by PCL or cutin. The second depolymerase shows interfacial activation, indicating that it is a lipase. PCL may thus be a substrate but not an inducer of depolymerases that degrade it, and screening microorganisms on medium with PCL as the sole source of carbon and energy may fail to reveal strains with active PCL depolymerases, because of the absence of an inducer. Surprisingly, Tween 80 induces both cutinase and lipase activities in wild-type F. solani.
A Framework for Environmental Assessment of CO2 Capture and Storage Systems

A FRAMEWORK FOR ENVIRONMENTAL ASSESSMENT OF CO2 CAPTURE AND STORAGE SYSTEMS Roger Sathre, Mikhail Chester, Jennifer Cain, and Eric Masanet Environmental Energy Technologies Division Lawrence Berkeley National Laboratory Berkeley, CA 94720 May 2012 Supported by the U.S. Department of Energy under Contract No. DE-­‐AC02-­‐05CH11231.
Sputtering yield of silicon by ellipsometry

Abstract Using ellipsometry, the ratio of sputtering yield to sticking probability for silicon is determined from experimentally measured quantities only. For 350 eV argon ions, the sputtering yield and the sticking probability are 0.12 and 0.27, respectively.
Instituteur Identities: Explaining the Nineteenth Century French Teachers' Movement

Recent social movement research has focused particularly on movements whose lack of organizational structures makes their emergence rather mysterious. The study of identity politics has been an important paradigm in this line of research, most of which examines the ‘new social movements’ of the past four decades. But, as Calhoun and others have noted, identities have always been a constitutive element of social movements. Analysis of new social movements has simply added a few new markers, like gender and race, to the standard identity repertoire of class and nation. The nineteenth century French teachers' movement is an excellent example of a resource-poor movement and, I argue, would not have been possible without a particular self-understanding on the part of the teachers. But, rather than draw from one of these standard identity markers and research paradigms, I use two tools derived from social scientific studies of how states impose identities on subject populations: categories and professionalism. ...
Substituent Effects on the Reversibility of Furan–Maleimide Cycloadditions

The effects of furan and maleimide substitution on the dynamic reversibility of their Diels–Alder reactivity have been investigated computationally and by 1H NMR spectroscopy. Furan and furan derivatives bearing methoxy, methyl, or formyl groups at their 2- or 3-positions were investigated with maleimide and maleimide derivatives bearing N-methyl, N-allyl, and N-phenyl substituents. Computational predictions indicate that electronic and regiochemical effects of furan substitution significantly influence their Diels–Alder reactivity with maleimide, with reaction free energies of exo adduct formation ranging from ΔG = −9.4 to 0.9 kcal/mol and transition state barriers to exo adduct formation ranging from ΔG⧧ = 18.9 to 25.6 kcal/mol. Much less variation was observed for the reactivity of N-substituted maleimide derivatives and furan, with reaction and transition state free energies each falling within a range of 1.1 kcal/mol. Dynamic exchange experiments monitored by 1H NMR spectroscopy support computational...
SPECIFIC AND RAPID EFFECTS OF ACOUSTIC STIMULATION ON THE TONOTOPIC DISTRIBUTION OF Kv3.1b POTASSIUM CHANNELS IN THE ADULT RAT

Abstract Recent studies have demonstrated that total cellular levels of voltage-gated potassium channel subunits can change on a time scale of minutes in acute slices and cultured neurons, raising the possibility that rapid changes in the abundance of channel proteins contribute to experience-dependent plasticity in vivo . In order to investigate this possibility, we took advantage of the medial nucleus of the trapezoid body (MNTB) sound localization circuit, which contains neurons that precisely phase-lock their action potentials to rapid temporal fluctuations in the acoustic waveform. Previous work has demonstrated that the ability of these neurons to follow high-frequency stimuli depends critically upon whether they express adequate amounts of the potassium channel subunit Kv3.1. To test the hypothesis that net amounts of Kv3.1 protein would be rapidly upregulated when animals are exposed to sounds that require high frequency firing for accurate encoding, we briefly exposed adult rats to acoustic environments that varied according to carrier frequency and amplitude modulation (AM) rate. Using an antibody directed at the cytoplasmic C-terminus of Kv3.1b (the adult splice isoform of Kv3.1), we found that total cellular levels of Kv3.1b protein—as well as the tonotopic distribution of Kv3.1b-labeled cells—was significantly altered following 30 min of exposure to rapidly modulated (400 Hz) sounds relative to slowly modulated (0–40 Hz, 60 Hz) sounds. These results provide direct evidence that net amounts of Kv3.1b protein can change on a time scale of minutes in response to stimulus-driven synaptic activity, permitting auditory neurons to actively adapt their complement of ion channels to changes in the acoustic environment.