cssi/SciSciGPT-SciSciNet huggingface dataset:
Exact diagonal representation of normal mode energy, occupation number, and heat current for phonon-dominated thermal transport.

Collective excitations of crystal vibrations or normal modes are customarily described using complex normal mode coordinates. While appropriate for calculating phonon dispersion, the mixed representation involving the complex conjugates does not allow the construction of equivalent phonon occupation number or modal dynamical quantities such as the energy or heat current specific to a wave-vector direction (q). Starting from a canonical solution that includes waves going to the left and right directions, we cast the Hamiltonian, normal mode population, and heat current in an exactly diagonalizable representation using real normal mode amplitudes. We show that the use of real amplitudes obviates the need for a complex modal heat current while making the passage to second quantization more apparent. Using nonequilibrium molecular dynamics simulations, we then compute the net modal energy, heat current, and equivalent phonon population in a linear lattice subjected to a thermal gradient. Our analysis paves a tractable path for probing and computing the direction-dependent thermal-phononic modal properties of dielectric lattices using atomistic simulations.Collective excitations of crystal vibrations or normal modes are customarily described using complex normal mode coordinates. While appropriate for calculating phonon dispersion, the mixed representation involving the complex conjugates does not allow the construction of equivalent phonon occupation number or modal dynamical quantities such as the energy or heat current specific to a wave-vector direction (q). Starting from a canonical solution that includes waves going to the left and right directions, we cast the Hamiltonian, normal mode population, and heat current in an exactly diagonalizable representation using real normal mode amplitudes. We show that the use of real amplitudes obviates the need for a complex modal heat current while making the passage to second quantization more apparent. Using nonequilibrium molecular dynamics simulations, we then compute the net modal energy, heat current, and equivalent phonon population in a linear lattice subjected to a thermal gradient. Our analysis paves a ...
Utility of High-Sensitivity and Conventional Troponin in Patients Undergoing Transcatheter Aortic Valve Replacement: Incremental Prognostic Value to B-type Natriuretic Peptide

High-sensitivity Troponin (hs-Tn) has emerged as a useful marker for patients with myocardial injury or heart failure. However, few studies have compared intermediate and hs-Tn in patients undergoing transcatheter aortic valve replacement (TAVR). Moreover, there remains uncertainty of which thresholds are the most useful for discriminating ventricular dysfunction or outcome. In this study we prospectively enrolled 105 patients with severe aortic stenosis (AS) who underwent TAVR as well as blood sampling for high-sensitivity (hs-TnI) and conventional troponin I (EXL-LOCI and RXL) assessment. Patients underwent comprehensive pre-procedure echocardiography. Ventricular dysfunction was defined using left ventricular mass index (LVMI), LV global longitudinal strain (LVGLS) and LV end-diastolic pressure. The mean age was 84.0 ± 8.7 years old and 60% were male sex with mean transaortic pressure gradient of 50.1 ± 16.0 mmHg and AVA of 0.63 ± 0.19 cm2. When using a threshold of 6 ng/L, 77% had positive hs-TnI while 27% had positive hs-TnI using recommended thresholds (16 ng/L for female and 34 ng/L for male). Troponin levels were higher in the presence of abnormal LV phenotypes. The strongest correlate of troponin was LVMI. During median follow-up of 375 days, 21 patients (20%) died. Lower threshold of hs-TnI and EXL-TnI was more discriminatory for overall mortality (Log-rank P = 0.03 for both), while higher threshold of hs-TnI (p = 0.75) and RXL-TnI were not (p = 0.30). Combining hs-TnI and BNP improved to predict long-term outcome (p = 0.004). In conclusion, hs-TnI levels correlated with the degree of LV dysfunction phenotypes. Furthermore, applying a lower threshold for hs-TnI performed better for outcome prediction than a recommended threshold in patients undergoing TAVR. Combining hs-TnI with BNP helped better risk stratification.
Private sector support of the farmer transition to certified organic production systems

Certified organic handling firms, situated between the farm and the consumer along the supply chain, rely on a predictable supply of organic ingredients and commodities to meet consumer demand for organic food. Yet organic firms often incur high transaction costs related to locating certified organic products. The transaction costs may be one reason that growth in organic farmland fails to keep pace with consumer demand for organic food. When costs are sufficiently high, certified organic handling firms may choose to directly support farmers as they undergo the 3-year transition process; support may take the form of providing advice or providing financial assistance. Analyzing primary data collected in 2017, we find that approximately 20% of certified organic firms in the sample assist farmers with the transition. The most common types of support focus on reducing technical barriers to organic farming and include providing advice on the organic standards and organic farming practices. Factors influencing the likelihood of a firm assisting with the transition to organic include firm size, function, share of procurement made locally, and the importance of organic to the firm’s business.
Leukocytosis after distal pancreatectomy and splenectomy as a marker of major complication.

Abstract Background The aim of this study was to analyze the associations between the degree of postoperative leukocytosis and major morbidity after elective distal pancreatectomy with splenectomy (DPS). Methods Retrospective review of patients undergoing DPS for pancreatic diseases (2013–2016). Receiver operating characteristic curves, Youden’s index, and area under the curve were used to identify ideal lab cut-off values and discriminatory ability of postoperative white blood cell count to detect complications. Results 158 patients underwent DPS. Median age was 57 years (range, 22–90) and 53% of patients were male. POD3 absolute WBC count ≥16 × 109/L or an increase in WBC count ≥9 × 109/L from preoperative baseline was associated with major morbidity after DPS (AUC 0.7 and 0.7, respectively). Conclusion Postoperative day three leukocytosis ≥16 × 109/L or an increase in WBC of ≥9 × 109/L from preoperative baseline should raise clinical awareness for major postoperative complication after DPS.
Nearly Optimal Robust Method for Convex Compositional Problems with Heavy-Tailed Noise.

In this paper, we propose robust stochastic algorithms for solving convex compositional problems of the form $f(\E_\xi g(\cdot; \xi)) + r(\cdot)$ by establishing {\bf sub-Gaussian confidence bounds} under weak assumptions about the tails of noise distribution, i.e., {\bf heavy-tailed noise} with bounded second-order moments. One can achieve this goal by using an existing boosting strategy that boosts a low probability convergence result into a high probability result. However, piecing together existing results for solving compositional problems suffers from several drawbacks: (i) the boosting technique requires strong convexity of the objective; (ii) it requires a separate algorithm to handle non-smooth $r$; (iii) it also suffers from an additional polylogarithmic factor of the condition number. To address these issues, we directly develop a single-trial stochastic algorithm for minimizing optimal strongly convex compositional objectives, which has a nearly optimal high probability convergence result matching the lower bound of stochastic strongly convex optimization up to a logarithmic factor. To the best of our knowledge, this is the first work that establishes nearly optimal sub-Gaussian confidence bounds for compositional problems under heavy-tailed assumptions.
Atrial Fibrillation in Transthyretin Cardiac Amyloidosis: Predictors, Prevalence, and Efficacy of Rhythm Control Strategies

Abstract Objectives This study sought to determine the incidence and prevalence of atrial fibrillation (AF) in transthyretin cardiac amyloidosis (ATTR-CA); to study the factors associated with the development of AF in this population; to study the prognostic implications of AF and maintenance of normal sinus rhythm (NSR) in patients with ATTR-CA; and to determine the impact of ATTR-CA stage on AF prevalence, outcomes, and efficacy of rhythm control strategies. Background AF is common in patients with ATTR-CA. The aim of this study was to determine the predictors, prevalence, and outcomes of AF in patients with ATTR-CA in addition to the efficacy of rhythm control strategies. Methods This was a retrospective cohort study of 382 patients with ATTR-CA diagnosed at our institution between January 2004 and January 2018. Means testing, and univariable and multivariable models were used. Results AF occurred in 265 (69%) patients. Factors associated with the development of AF included older age, advanced ATTR-CA stage, and higher left atrial volume index. Antiarrhythmic therapy (AAT) was used in 35% of patients with AF; cardioversion was performed in 45%, and 5% underwent AF ablation. Rhythm control strategies were substantially more effective when performed earlier in the disease course. During a mean follow-up of 35 months, no difference in mortality between patients with AF and those without AF was observed (65% vs. 49%; p = 0.76). On Cox proportional hazards analyses, maintenance of normal sinus rhythm and tafamidis use were associated with improved survival, whereas advanced ATTR-CA stage and higher New York Heart Association functional class were associated with increased mortality. Conclusions With advancing ATTR-CA stage, AF became more prevalent, occurring in 69% of our entire study cohort. Rhythm control strategies including AAT, direct-current cardioversion, and AF ablation were substantially more effective when performed earlier during the disease course.
Combining Items From 3 Federally Mandated Assessments Using Rasch Measurement to Reliably Measure Cognition Across Postacute Care Settings.

Abstract Objective To combine items from the Functional Independence Measure, Minimum Data Set (MDS) 2.0, and the Outcome and Assessment Information Set (OASIS)-B to reliably measure cognition across postacute care settings and facilitate future studies of patient cognitive recovery. Design Rasch analysis of data from a prospective, observational cohort study. Setting Postacute care inclusive of inpatient rehabilitation facilities, skilled nursing facilities, and home health agencies. Participants Patients (N=147) receiving rehabilitation services. Interventions Not applicable. Main Outcome Measures Functional Independence Measure, MDS 2.0, and the OASIS-B. Results Six cognition items demonstrated good construct validity with no misfitting items, unidimensionality, good precision (person separation reliability, 0.95), and an item hierarchy that reflected a clinically meaningful continuum of cognitive challenge. Conclusions This is the first attempt to combine the cognition items from the 3 historically, federally mandated assessments to create a common metric for cognition. These 6 items could be adopted as standardized patient assessment data elements to improve cognitive assessment across postacute care settings.
Three-dimensional phase field modeling of columnar to equiaxed transition in directional solidification of Inconel 718 alloy

Abstract Understanding the columnar to equiaxed transition (CET) is vital in production of materials with superior properties using casting, welding, and additive manufacturing processes. In this study, a three dimensional (3D) phase field-lattice Boltzmann (PF-LB) model was developed to simulate the CET in directional solidification of Inconel 718 alloy. The phase field (PF) method was used to determine the solid/liquid transition. The solute diffusion equation was solved by the lattice Boltzmann method (LBM), due to its suitability for parallel processing and its simplicity in terms of modeling complex boundaries. A CET solidification map was developed for different temperature gradients and growth rates and the evolution of dendrites for equiaxed, columnar, and mixed regimes was studied. The resulting microstructure for different growth regimes was demonstrated and discussed in terms of grain size and orientation. In addition, the variation of maximum solute concentration along the sample height was investigated. It was found that while initial grain size does not affect the average grain size for equiaxed growth, it affects the PDAS for columnar growth significantly. A model was proposed to predict the primary dendrite arm spacing for columnar growth in a wide range of temperature gradient, solidification rate, and initial grain size. The novelty of this model is in the inclusion of the effect of initial grain size, which is important in processes that involve melting and solidification on a preexisting substrate, such as welding and additive manufacturing.
Traceless Redox-Annulations of Alicyclic Amines

Amines such as 1,2,3,4-tetrahydroisoquinoline undergo redox­-neutral annulations with ortho-(nitromethyl)benzaldehyde. Benzoic­ acid acts as a promoter in these reactions, which involve concurrent amine α-C–H bond and N–H bond functionalization. Subsequent removal of the nitro group provides access to tetrahydroprotoberberines not accessible via typical redox-annulations. Also reported are decarboxylative annulations of ortho-(nitromethyl)benzaldehyde with proline and pipecolic acid.
Effective Management Practices for Increasing Native Plant Diversity on Mesquite Savanna-Texas Wintergrass-Dominated Rangelands

Abstract Throughout the Rolling Plains and Cross Timbers ecoregions of Texas, native grassland plant communities have been converted into low-diversity plant communities by long-term, intensive overgrazing by cattle and fire suppression. Much of the historical plant community has become dominated by annuals, Texas wintergrass (Nassella leucotricha), and honey mesquite (Prosopis glandulosa). This degradation has been so severe that many native bird species, including Northern bobwhite (Colinus virginianus), have experienced drastic population declines. We conducted a small-plot study to determine effective management actions for transforming mesquite savanna−Texas wintergrass communities to diverse native plant communities supportive of native wildlife species. We tested multiple management practices following mechanical mesquite brush removal, including seeding, timed treatments of herbicide, prescribed burns, and high-intensity, short-duration cattle grazing. Results indicated that plots receiving early spring treatments of herbicide followed by burning and grazing over 2 consecutive yr best reduced cool-season grasses and promoted overall restoration goals by increasing native warm-season grass and forb establishment.
Revisiting the reaction of dicarbonyls in aerosol proxy solutions containing ammonia: the case of butenedial

Abstract. Reactions in aqueous solutions containing dicarbonyls (especially the α -dicarbonyls methylglyoxal, glyoxal, and biacetyl) and reduced nitrogen (NH x ) have been studied extensively. It has been proposed that accretion reactions from dicarbonyls and NH x could be a source of particulate matter and brown carbon in the atmosphere and therefore have direct implications for human health and climate. Other dicarbonyls, such as the 1,4-unsaturated dialdehyde butenedial, are also produced from the atmospheric oxidation of volatile organic compounds, especially aromatics and furans, but their aqueous-phase reactions with NH x have not been characterized. In this work, we determine a pH-dependent mechanism of butenedial reactions in aqueous solutions with NH x that is compared to α -dicarbonyls, in particular the dialdehyde glyoxal. Similar to glyoxal, butenedial is strongly hydrated in aqueous solutions. Butenedial reaction with NH x also produces nitrogen-containing rings and leads to accretion reactions that form brown carbon. Despite glyoxal and butenedial both being dialdehydes, butenedial is observed to have three significant differences in its chemical behavior: (1) as previously shown, butenedial does not substantially form acetal oligomers, (2) the butenedial/OH − reaction leads to light-absorbing compounds, and (3) the butenedial/NH x reaction is fast and first order in the dialdehyde. Building off of a complementary study on butenedial gas-particle partitioning, we suggest that the behavior of other reactive dialdehydes and dicarbonyls may not always be adequately predicted by α -dicarbonyls, even though their dominant functionalities are closely related. The carbon skeleton (e.g., its hydrophobicity, length, and bond structure) also governs the fate and climate-relevant properties of dicarbonyls in the atmosphere. If other dicarbonyls behave like butenedial, their reaction with NH x could constitute a regional source of brown carbon to the atmosphere.
Donor Bicuspid Aortic Valve: Double Trouble or No Problem?

Introduction Valvular disease in pediatric donor hearts may be a relative contraindication to graft use. Outcomes following use of donor hearts with milder forms of valvular disease have not been previously reported. We describe 4 cases of pediatric heart transplantation (HTx) in which the donor heart had a bicuspid aortic valve (BAV). Case Report Of the 469 HTx performed at our center since 1985, 4 donor hearts had a BAV. All recipients were female; median age 11 years (range 0.3 to 19 years). In all cases, the BAV was not discovered until after HTx. All donors were less than 30 years old. The patients were followed for a median of 6 years (range 2 to 9 years) with all patients alive at last follow up. Two patients transferred to adult care and 2 patients are followed by our clinic. In follow up, no patient required an aortic valve intervention or had infective endocarditis. At last review, no patient had greater than mild aortic insufficiency or more than mild aortic stenosis. Three patients developed mild to moderate left ventricular hypertrophy in the first year post-transplant that improved over time. One patient experienced a peri-operative embolic stroke at time of transplant unrelated to the bicuspid aortic valve. Summary On short- and intermediate-term follow up, donor hearts with bicuspid aortic valve demonstrated acceptable graft longevity and valvular function. A functionally normal bicuspid aortic valve in a pediatric heart transplant donor should not be a contraindication to organ acceptance.
Teaching Use of Social Media as a Public Health Education & Advocacy Tool

Today’s public health students interact with social media on a daily basis. Most students use a social media tool such as Twitter, Facebook or Linkedin on a daily basis. Yet few students know how to use social media in order to convey critical public health research findings, organize community groups or advocate policy needs. This study explores the use of scaffolding to teach public health students how to use social media to conduct research, draft findings and present complex public health ideas in a manner accessible to the general public. Scaffolding techniques were used in three courses over six semesters. Students were required to work in groups to create a white paper, blogs, a website and tweets. Students were given periodic surveys to assess the experience. The study concludes that scaffolding is an effective means to teach public health students how to use social media as a supplement to traditional research to publish findings, sway opinions and promote public health.
Supply chain diversity buffers cities against food shocks.

Food supply shocks are increasing worldwide1,2, particularly the type of shock wherein food production or distribution loss in one location propagates through the food supply chain to other locations3,4. Analogous to biodiversity buffering ecosystems against external shocks5,6, ecological theory suggests that food supply chain diversity is crucial for managing the risk of food shock to human populations7,8. Here we show that boosting a city’s food supply chain diversity increases the resistance of a city to food shocks of mild to moderate severity by up to 15 per cent. We develop an intensity–duration–frequency model linking food shock risk to supply chain diversity. The empirical–statistical model is based on annual food inflow observations from all metropolitan areas in the USA during the years 2012 to 2015, years when most of the country experienced moderate to severe droughts. The model explains a city’s resistance to food shocks of a given frequency, intensity and duration as a monotonically declining function of the city’s food inflow supply chain’s Shannon diversity. This model is simple, operationally useful and addresses any kind of hazard. Using this method, cities can improve their resistance to food supply shocks with policies that increase the food supply chain’s diversity. An intensity−duration−frequency model linking food shock risk to supply chain diversity in the USA finds that boosting a city’s food supply chain diversity increases the resistance of a city to food shocks of mild to moderate severity.
Terminology and Methods in Dietary Restriction Research

Dietary restriction (DR) entailing a 30%–70% reduction in caloric intake done without malnutrition favorably alters gerontologic and pathologic outcomes in mice and rats (for reviews see: Holehan and Merry 1986; Masoro 1988; Weindruch and Walford 1988). Over the many years since McCay et al. (1935) first described the life span-increasing action of DR in rats, the model has evolved from an interesting peculiarity to a uniquely powerful tool for investigating the retardation of aging and disease processes. DR stands out from the many putative antiaging interventions tested in rodents because it is the only one which retards a broad spectrum of age-related biologic changes (Weindruch and Walford 1988), reduces mortality rates (Sacher 1988), and extends maximum life span (Ross 1978; and Schneider and Reed 1985).
Purification and characterization of an insulin-like growth factor II variant from human plasma

An insulin-like growth factor II variant (IGF-II variant) was purified from Cohn fraction IV1 of human plasma by ion exchange, gel filtration, and reversed-phase high pressure liquid chromatography. The amino-terminal sequence of the first 35 amino acid residues showed a replacement of Ser-29 of IGF-II with the tetrapeptide Arg-Leu-Pro-Gly of IGF-II variant. Peptides isolated and sequenced after digestion with endoproteinase Asp-N and endoproteinase Glu-C disclosed no differences with the sequence predicted from an IGF-II variant cDNA clone isolated by Jansen, M., van Shaik, F. M. A., van Tol, H., Van den Brande, J. L., and Sussenbach, J. S. (1985) FEBS Lett., 179, 243-246. The molecular ion of intact IGF-II variant was 7809.4 mass units, as measured by plasma desorption mass spectrometry. This is in close agreement with the molecular ion of 7812.8 mass units calculated from the determined sequence and indicates the entire amino acid sequence had been accounted for. Binding of IGF-II variant to purified insulin-like growth factor I (IGF-I) receptors demonstrated a 2-3-fold lower affinity for this receptor compared with IGF-I or IGF-II. The dissociation constants for IGF-I, IGF-II, and IGF-II variant are 0.23, 0.38, and 0.80 nM, respectively. In a growth assay, the concentration of IGF-II and IGF-II variant required to stimulate the half-maximal growth of MCF-7 cells was 4 and 13 nM, respectively. Finally, the amount of IGF-II variant that can be purified by this method constitutes approximately 25% of the total IGF-II isolated from Cohn fraction IV1 of human plasma.
Communication and Democratic Reform in South Africa

The book examines the reform of the communication sector in South Africa as a detailed and extended case study in political transformation - the transition from apartheid to democracy. The reform of broadcasting, telecommunications, the state information agency and the print press from apartheid-aligned apparatuses to accountable democratic institutions took place via a complex political process in which civil society activism, embodying a post-social democratic ideal, largely won out over the powerful forces of formal market capitalism and older models of state control. In the cautious acceptance of the market, the civil society organizations sought to use the dynamism of the market while thwarting its inevitable inequities. Forged in the crucible of a difficult transition to democracy, communication reform in South Africa was navigated between the National Party's embrace of the market and the African National Congress leadership's default statist orientation.
The role of size and colour pattern in protection of developmental stages of the red firebug (Pyrrhocoris apterus) against avian predators

We investigated how predator/prey body-size ratio and prey colour pattern affected efficacy of prey warning signals. We used great and blue tits (Parus major and Cyanistes caeruleus), comprising closely related and ecologically similar bird species differing in body size, as experimental predators. Two larval instars and adults of the unpalatable red firebug (Pyrrhocoris apterus), differing in body size and/or coloration, were used as prey. We showed that prey body size did not influence whether a predator attacked the prey or not during the first encounter. However, smaller prey were attacked, killed, and eaten more frequently in repetitive encounters. We assumed that body size influences the predator through the amount of repellent chemicals better than through the amount of optical warning signal. The larger predator attacked, killed and ate all forms of firebug more often than the smaller one. The difference between both predators was more pronounced in less protected forms of firebug (chemically as well as optically). Colour pattern also substantially affected the willingness of predators to attack the prey. Larval red–black coloration did not provide a full-value warning signal, although a similarly conspicuous red-black coloration of the adults reliably protected them. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 890–898.
A hybrid genetic algorithm for the traveling salesman problem using generalized partition crossover

We present a hybrid genetic algorithm that incorporates the Generalized Partition Crossover (GPX) operator to produce an algorithm that is competitive with the state of the art for the Traveling Salesman Problem (TSP). GPX is respectful, transmits alleles and is capable of tunneling directly to new local optima. Our results show that the hybrid genetic algorithm quickly finds optimal and near optimal solution on problems ranging from 500 to 1817 cities using a population size of 10. It is also superior to Chained-LK given similar computational effort. Additional analysis shows that all the edges found in the globally optimal solution are present in a population after only a few generations in almost every run. Furthermore the number of unique edges in the population is also less than twice the problem size.
A PET ligand for in vivo imaging of oxytocin receptors within the cynomolgus monkey brain

401 Objectives The neural oxytocin (OT) system has been linked to social behavior disorders on multiple levels. Administration of OT to individuals with autism spectrum disorders (ASD) has been shown to alleviate symptoms and improve participation in pro-social behaviors [1,2]. Genetic studies have linked polymorphisms, DNA methylation, and cortical expression of the OT receptor gene to ASD. The neural OT receptor density has been directly correlated to specific social behaviors such as pair-bonding and maternal behavior in voles [3]. A potent PET ligand which selectively binds to the OT receptor in vivo could provide insights into the underlying causation of these social behavioral disorders. The primary objective of this project was to develop a ligand fitting this profile and investigate it’s functionality in rodent and non-human primate subjects. Methods The compound 1-(1-(2-(2-(2-fluoroethoxy)-4-(piperidin-4-yloxy)phenyl)acetyl)piperidin-4-yl)-3,4-dihydroquinolin-2(1H)-one (ALS-II-69) was synthesized and subjected to human cell assays to determine receptor affinities [4]. The positron emitting analogue, [F-18]ALS-II-69, was then synthesized and investigated via PET imaging using rat and non-human primate models. Results Human cell assays determined ALS-II-69 to be potent and selective for the OT receptor (Ki=17nm). The positron emitting analogue, [F-18]ALS-II-69, was synthesized with uncorrected yields up to 18% and radiochemical purity >99%. Imaging studies with both rat and non-human primate models showed specific uptake in brain regions believed to express the OT receptor. A chase study confirmed specific uptake in the brain of the non-human primate model by administering the cold standard 45 minutes post-injection of [F-18]ALS-II-69. Conclusions A novel PET ligand for imaging OT receptors, [F-18]ALS-II-69, has been developed and partially validated in rat and non-human primate models. Research Support NIMH Grant 1R21MH090776-0
Gene knockouts, in vivo site-directed mutagenesis and other modifications using the delitto perfetto system in Saccharomyces cerevisiae

Gene manipulation serves the purpose of providing a better understanding of the function of specific genes as well as for developing novel variants of the genes of interest. The generation of knockout genes, the alteration, depletion, or enhancement of a particular gene function through the generation of specific gene mutations, or the generation of random mutations in a gene are all essential processes for gene manipulation. The genome of the yeast Saccharomyces cerevisiae is relatively easy to modify, owing to its efficient homologous recombination (HR) system. Gene knockout can be a very simple, one-step approach to eliminate a gene by substituting its DNA sequence with that of a genetic marker. Differently, desired mutations can be introduced into a gene by replacing the sequence of the normal gene with that of the mutated gene. Recombinant DNA can be created in vitro and then introduced into cells, most often exploiting the endogenous recombination system of the cells. However, unless the desired mutation gives a particular phenotype, a bottleneck of 'recombineering' is the requirement of a selection system to identify the recombinant clones among those unmodified. Even in an organism like yeast where the level of HR is highly above the incidence of random integration, the frequency of homologous targeting is in the range of 10(-4)-10(-6) depending on the length of the homology used (Wach et al., 1994). Thus, a selection system is always required to identify the targeted clones. Counterselectable markers, such as URA3, LYS2, LYS5, MET15, and TRP1 (Bach and LaCroute, 1972; Chattoo et al., 1979; Singh and Sherman, 1974; Toyn et al., 2000), are widely utilized in yeast and can be recycled for additional usage in the same yeast strain. If the marker is not eliminated or it is popped out via site-specific recombination between direct repeats, such as in the Flp/FRT or Cre/Lox systems, a heterologous sequence is left as a scar at the site of the modified DNA (Storici et al., 1999; Sauer, 1987). The presence of such scars can threaten the genomic stability of the strain and/or limit the number of successive genetic manipulations for that strain. Here, we describe the delitto perfetto approach for in vivo mutagenesis that combines the practicality of a general selection system with the versatility of synthetic oligonucleotides for targeting (Storici et al., 2001). It provides for generation of gene knockouts and almost any sort of mutation and genome rearrangement via HR. The delitto perfetto in vivo mutagenesis technique is designed for efficient and precise manipulation of yeast strains in a two-step process spanning ~2 weeks. Here, we present the theory and procedures of the delitto perfetto technique.
Launch capabilities to over 10 km/s

A systematic study is described which addresses the technical issues associated with launching flier plates to hypervelocities. Structured, time-dependent, uniform, high-pressure pulses are needed to drive flier plates to hypervelociites without melting or fracturing the plate. This is achieved by using a graded-density impactor to impact a flier plate at high velocities on a two-stage light-gas gun. We have used this method to launch titanium and aluminum alloy plates to velocities of 9.5 km/s and 10.4 km/s, respectively. A method is proposed to extend the launch capabilities to velocities in excess of 14 km/s.
Perioperative Glycemic Control and the Effect on Surgical Site Infections in Diabetic Patients Undergoing Foot and Ankle Surgery

Introduction. Diabetes mellitus is one of the leading causes of hyperglycemia in the perioperative setting. Hyperglycemia has been shown to cause increased risk of surgical site infections (SSIs) in multiple surgical specialties, but to our knowledge it has not been investigated for orthopaedic foot and ankle surgery. The aim of this study was to determine if hyperglycemia increased the rate of SSI in elective, diabetic patients that required perioperative hospitalization. Methods. A total of 348 consecutive inpatients after foot and ankle surgery were retrospectively evaluated. Patients who had a random serum glucose ≥200 mg/dL during the admission (Group 1) were compared to patients whose serum glucose never exceeded 200 mg/dL (Group 2). Results. Our 2 groups were similar with regard to age, gender, and body mass index. Twenty-one of 176 patients (11.9%) whose serum glucose was ≥200 mg/dL during the admission developed an SSI as compared to 9 of 172 patients (5.2%) whose serum glucose remained <200 mg/d...
The relation between dry vortex merger and tropical cyclone genesis over the Atlantic Ocean

Using 33 year European Centre for Medium-Range Weather Forecasts Re-Analysis Interim reanalysis in the months of August and September, we found that more than half of the low-level, moist vortices (called wet vortices) originating from south of the African easterly jet merged with a shallow, dry vortex from the north after leaving the West African coast. A dry vortex involved with the merger process is referred to as a D-vortex, and the process is referred to as a D-vortex merger. Dry vortices influenced by more intense African easterly waves moved southwestward and had a greater potential to serve as D-vortices in the merger process. The D-vortex merger occurred in the predepression stage of 70% of tropical cyclones (TCs) that formed in the Atlantic main development region and in 55% of nondeveloping systems. Further analysis showed that developing systems with the D-vortex merger (DM) were statistically dominated by a more intense wet vortex whose 500 hPa relative humidity was also significantly higher, while nondeveloping systems with the D-vortex merger (NM) were dominated by a more intense dry vortex. The average intensity of wet vortices for DM was more intense than that for NM, significant at a 95% confidence level. Moreover, warmer Saharan air was observed for DM than NM. While TC genesis is largely controlled by the large-scale environment over ocean, differences in vortex characteristics and environment over northwestern Africa between DM and NM could potentially help predict whether a tropical system associated with the D-vortex merger will ultimately evolve into an Atlantic TC.
Microstructure of copper following high dose 14-MeV Cu ion irradiation

Abstract High-purity copper has been irradiated with 14-MeV Cu ions to peak doses of 40 dpa over the temperature range of 100–500°C. Examination of the foils in a transmission electron microscope revealed that no significant amount of void formation had occurred, in conflict with previous irradiation studies. Instead, a high density of stacking fault tetrahedra (SFT) were observed. The defect cluster density is constant for irradiation temperatures ⩽ 200°C, and the density decreases rapidly with irradiation temperature ⩾ 300°C. It is postulated that the absence of voids is due to the low oxygen content of the copper foils (
The reinforcing properties of the mixed agonist-antagonist buprenorphine as assessed by brain-stimulation reward.

Abstract The effect of buprenorphine on the threshold for rewarding brain stimulation to the medial forebrain bundle-lateral hypothalamus was determined in rats using a rate-independent psychophysical method. Increased sensitivity to rewarding brain stimulation (i.e., lowering of the reward threshold) was used as the measure of a drug's reinforcing action. Buprenorphine (SC) produced a significant dose-dependent lowering of the reward threshold, with effective doses varying from 0.004–0.06 mg/kg. These results are consistent with buprenorphine's euphoria producing effects in humans and its ability to sustain self-administration in animals and suggest that buprenorphine may have abuse potential.
The GAP Portion of Pseudomonas Aeruginosa Type III Secreted Toxin ExoS Upregulates Total and Surface Levels of Wild Type CFTR

Background: Pseudomonas aeruginosa (PA) infections account for a large percentage of fatal hospital acquired pneumonias. One of the PA Type III secreted toxin (TTST) ExoS, a bifunctional protein with N-terminal GTPase activating protein (GAP) and C-terminal ADP rybosyl transferase (ADPRT) activities, significantly contributes to PA virulence by targeting small molecular weight G-proteins (SMWGP). In this study, we have looked at one of the mechanisms by which the GAP portion of ExoS (ExoS-GAP) mediates cellular toxicity. Methods: The effects of ExoS-GAP on CFTR trafficking were studied in CFBE41o- Kir 2.2 and MDCK cell lines stably expressing CFTR using a transient transfection system. Results: Transient transfection of ExoS-GAP increased the total and surface protein levels of mature wild type CFTR in epithelial cells stably expressing wild type (WT) CFTR. The effect of ExoS-GAP was specific to CFTR in bronchial epithelial cells since it did not affect the total protein levels of Na+/K+ATPase, another membrane protein. A point mutation in the ExoS GAP domain (R146K), known to disrupt its catalytic GAP activity, abolished the effect of ExoS-GAP on WT CFTR. Lysosomal inhibition studies with Bafilomycin A1 indicate that ExoS-GAP decreased lysosomal degradation of the mature WT CFTR with concomitant increase in the total levels of mature WT CFTR. However, ExoS-GAP did not increase the total protein levels of ∆F508CFTR. Conclusion: The GAP portion of the PA TTST ExoS increases the total and surface levels of wild type CFTR in vitro mammalian cell system. The effect of ExoS-GAP on WT CFTR total protein levels provides new insight into understanding the virulent pathophysiology of PA infections.
seeing the european union through american eyes: the EU as a reflection of the american experience

The lack of power exercised by the European Union (EU) in the international security arena explains its relative invisibility in the US. When Americans do recognise the EU, their interpretations of American history shape their responses to it. Whether puzzled by the loss of sovereignty or by the continuing strength of national identity, the American understanding of European integration cannot be divorced from Americans’ own understanding of the American process of nation-building and the exercise of federal power.
An Inverted Repeat Borders a Fivefold Amplification in Satellite DNA

One variant of a complex satellite DNA of the Bermuda land crab is significantly longer than the average repeat unit of the satellite. The extra DNA in the variant is accounted for by a fivefold tandem amplification of a 0.142-kilobase sequence. The amplified sequence is bounded by a tetranucleotide inverted repeat; the upstream arm of the inverted repeat is missing from two other variants of the satellite. The latter variants contain only one copy of a sequence that is closely related to the amplified sequence. By contrast, in several satellite DNA's of other organisms, extra DNA is inserted.
Semirelativistic potential model for charmonium

The charmonium spectrum is investigated with the use of a semirelativistic quantum-chromodynamic potential model. As in our earlier nonrelativistic model, the quark-antiquark potential consists of a perturbative part, which includes the complete one-loop radiative correction to the one-gluon-exchange interaction, and a linear scalar-exchange confining part. We find that the semirelativistic model leads to closer agreement between the theoretical and observed energy levels, yields a larger value of the charmed-quark mass, and significantly affects the leptonic and E1 transition widths.
Analysis of the Regulatory Role of BAFF in Controlling the Expression of CD21 and CD23

Abstract The TNF family member BAFF serves to promote the survival and differentiation of maturing splenic B cells. The major receptor for BAFF (BAFF-R) is expressed by the transition 2, marginal zone and follicular, mature conventional B-2 cell populations; functional BAFF/BAFF-R signaling is required for T1 to T2 cell B cell maturation. Induced expression of CD23 and CD21 is also coincident with the T1 to T2 maturation stage. A key question we address in this report is if BAFF signaling directly induces CD21 and CD23 gene transcription and expression at this B cell transition point, or if their expression is simply coincident with B cell maturation and differentiation. We present data that supports the contention that BAFF does not preferentially induce the expression of CD23 or CD21 at the T1 to T2 transition, nor does exogenous BAFF lead to preferential increased expression of these proteins/genes in mature B cell populations. The analysis of LPS-induced splenic B cells from BAFF-R defective (A/WySnJ) mice did not show the preferential induction of expression of CD21 or CD23 that might have been expected if NF-κB-p52 protein was lacking due to insufficient BAFF-R signaling in cells bearing this mutation. Indeed, chromatin immunoprecipitation analysis demonstrated stable NF-κB-p52 complexes on CD21 and CD23 genes obtained from both wild type and A/WySnJ B cells. FACS analysis of splenic B cells from 1-, 2-, 3- and 6-week-old A/WySnJ mice demonstrated a block in differentiation (thus reducing overall B cell numbers) resulting in a failure of such cells to express CD21 but allowing for the expression level of CD23 per cell to reach levels approaching wild type. We have dubbed this CD23HICD21LO subset as the T1b transition B cell. These data support the recognized role of BAFF as promoting the survival and differentiation of splenic B cells but do not support a model of BAFF signaling directly inducing the expression of the CD21 and CD23 proteins via translocation of NF-κB-p52 species.
Development of osmotic and ionic regulation in juvenile coho salmon Oncorhynchus kisutch

Abstract 1. 1. The developmental pattern for the osmotic and ionic regulatory system during the juvenile phase of the life cycle was determined. Measurements of survival time were made monthly as were changes in blood osmotic, sodium and chloride concentrations following exposure to sea water ( salinity = 30‰ ). 2. 2. The development of sea-water adaptation preceded seaward migration and parr-smolt transformation by 6–7 months. No regression of adaptation was observed following the terminal stages of the migration period. 3. 3. Sea-water survival for various salinities ( 20‰→30‰ ) was shown to be a function of size and not chronological age. Relative survival times between certain species of the genus Salmo were compared to Oncorhynchus kisutch. 4. 4. Variability of the osmotic and ionic regulatory system was indicated by the deviation between blood concentrations (i.e. mOsm/1, mEquiv. Na+/1 and mEquiv. Cl−/1 of fresh-water fish (control) and fish exposed to sea water during the pre-migratory, migratory and post-migratory periods.
Effects of static antiferromagnetism on superconductivity

Abstract The only effect of static antiferromagnetism on Tc and Δ is replacement in the gap equation of the electron density of states for the nonmagnetic crystal by that of the antiferromagnet. This result is obtained only when complicated spin structure of the Cooper pairing and magnetic Umklapp processes in the electron-electron interaction are both included completely.
Programs in Practice: A Literature-Based Approach to Character Education

(1997). Programs in Practice: A Literature-Based Approach to Character Education. Kappa Delta Pi Record: Vol. 33, No. 3, pp. 112-114.
The ability of walnut extract and fatty acids to protect against the deleterious effects of oxidative stress and inflammation in hippocampal cells.

AbstractPrevious research from our lab has demonstrated that dietary walnut supplementation protects against age-related cognitive declines in rats; however, the cellular mechanisms by which walnuts and polyunsaturated fatty acids (PUFAs) may affect neuronal health and functioning in aging are undetermined.ObjectivesWe assessed if pretreatment of primary hippocampal neurons with walnut extract or PUFAs would protect cells against dopamine- and lipopolysaccharide-mediated cell death and calcium dysregulation.MethodsRat primary hippocampal neurons were pretreated with varying concentrations of walnut extract, linoleic acid, alpha-linolenic acid, eicosapentaenoic acid, or docosahexaenoic acid prior to exposure to either dopamine or lipopolysaccharide. Viability was assessed using the Live/Dead Cellular Viability/Cytotoxicity Kit. Also, the ability of the cells to return to baseline calcium levels after depolarization was measured with fluorescent imaging.ResultsResults indicated that walnut extract, alpha-li...
Study of the Theoretical Potential of Thermochemical Exhaust Heat Recuperation for Internal Combustion Engines

A detailed thermodynamic analysis of thermochemical recuperation (TCR) applied to an idealized internal combustion engine with single-stage work extraction is presented. Results for several different fuels are included. For a stoichiometric mixture of methanol and air, TCR can increase the estimated ideal engine second law efficiency by about 3% for constant pressure reforming and over 5% for constant volume reforming. For ethanol and isooctane, the estimated second law efficiency increases for constant volume reforming are 9 and 11%, respectively. The second law efficiency improvements from TCR result primarily from the higher intrinsic exergy of the reformed fuel and pressure boost associated with the gas mole increase. Reduced combustion irreversibility may also yield benefits for future implementations of combined cycle work extraction.
Biochemistry and molecular genetics of cystathionine β-synthase deficiency

Homocysteine is an independent risk factor for arteriosclerotic disease. Deficiency of cystathionine β-synthase (CBS) is the major cause of inherited homocysteinemia. The CBS gene is 25–30 kbp long and encodes a subunit of 63 kDa. The active form of the enzyme is a homotetramer that contains one heme and one pyridoxal 5′-phosphate per each subunit. It can also bind 1 mol of S-adenosylmethionine per mol of subunit. To date, an analysis of 205 homocystinuric alleles has been performed and 64 mutations found. The best studied, relatively “homogenous” patient populations are those of Ireland, Holland, and Italy. While the overall frequency of the two most frequent mutations is 24% for I278T and 31% for G307S, the breakdown between the countries varies greatly. For instance, the B6-nonresponsive G307S mutation accounts for > 70% alleles in Ireland and B6-responsive I278T mutation on the continent approaches 45%. In conclusion, further research is needed to define the mutations in individual countries to facilitate screening and genotype/phenotype correlations. Future biochemical studies will likely elucidate the role of heme in the enzyme and the tertiary structure of CBS.