Role of imine isomerization in the stereocontrol of the Staudinger reaction between ketenes and imines.

Computational-experimental analysis has allowed determining that the stereochemistry of the Staudinger reaction between ketenes and imines is strongly associated with the nature of the imine, which affects the two steps of the reaction. The first step, namely the nucleophilic attack of the sp-hybridized nitrogen atom of the imine on the sp-hybridized carbon atom of the ketene, is affected by the energetically accessible isomerization patterns of the imine. The second step consists of a conrotatory electrocyclization of the zwitterionic intermediate formed in the previous step.

Trends in total hip arthroplasty.

This article discusses developments in total hip arthroplasty related to the use of highly cross-linked polyethylene (HXLPE) liner material as the new standard of care for acetabular cup articulation surfaces. The pathologic implications of metal-on-metal hip prostheses in asymptomatic patients also are discussed.

A Versatile Method for the Protection of Carbonyl Compounds by Camphor Sulfonic Acid.

Background: Carbonyl groups are important functional groups and they play a key role in organic chemistry. This group needs to be protected in multistep synthesis against various reagents for a counter-reaction. The effort towards developing an efficient methodology for the protection of car-bonyl functional group is always a demanding reaction.

Seasonal detection of atrazine and atzA in man-made waterways receiving agricultural runoff in a subtropical, semi-arid environment (Hidalgo County, Texas, USA).

Atrazine is a widely-used herbicide that can impact non-target organisms in the environment but can be biologically degraded by several types of microorganisms. In this study, the gene atzA, which encodes for the initial step in bacterially-mediated atrazine degradation, was used as an indicator of atrazine pollution in agricultural canals located in Hidalgo County, Texas, USA. The concentration of atrazine and atzA were monitored once per month for 12 months during 2010-2011.

Expert elicitation on the uncertainties associated with chronic wasting disease.

A high degree of uncertainty exists for chronic wasting disease (CWD) transmission factors in farmed and wild cervids. Evaluating the factors is important as it helps to inform future risk management strategies. Expert opinion is often used to assist decision making in a number of health, science, and technology domains where data may be sparse or missing.

Design, synthesis, and analysis of antagonists of GPR55: Piperidine-substituted 1,3,4-oxadiazol-2-ones.

A series of 1,3,4-oxadiazol-2-ones was synthesized and tested for activity as antagonists at GPR55 in cellular beta-arrestin redistribution assays. The synthesis was designed to be modular in nature so that a sufficient number of analogues could be rapidly accessed to explore initial structure-activity relationships. The design of analogues was guided by the docking of potential compounds into a model of the inactive form of GPR55.

Cry-like genes, in an uncommon gene configuration, produce a crystal that localizes within the exosporium when expressed in an acrystalliferous strain of Bacillus thuringiensis.

Cry proteins are pesticidal toxins produced by the bacterium Bacillus thuringiensis (Bt), which aggregate in sporulating cells to form a crystal. Except in a relatively few cases, these crystals are located outside the exosporium that surrounds the spore. Bt2-56 is a strain of Bt that has the relatively uncommon characteristic of locating its Cry protein-containing crystal within the exosporium, and in association with a long, multifiber filament.

Solid-Liquid Self-Adaptive Polymeric Composite.

A solid-liquid self-adaptive composite (SAC) is synthesized using a simple mixing-evaporation protocol, with poly(dimethylsiloxane) (PDMS) and poly(vinylidene fluoride) (PVDF) as active constituents. SAC exists as a porous solid containing a near equivalent distribution of the solid (PVDF)-liquid (PDMS) phases, with the liquid encapsulated and stabilized within a continuous solid network percolating throughout the structure. The pores, liquid, and solid phases form a complex hierarchical structure, which offers both mechanical robustness and a significant structural adaptability under external forces.

Optimization of RGD-Containing Cyclic Peptides against αvβ3 Integrin.

We have previously reported the use of one-bead-one-compound (OBOC) combinatorial technology to develop a disulfide cyclic, Arg-Gly-Asp-containing octapeptide LXW7 (cGRGDdvc), that targets αvβ3 integrin with high affinity and specificity. αvβ3 integrin is known to be overexpressed in many cancers and in tumor vasculature, and it has been established as a cancer therapeutic target. To further optimize LXW7, we have performed systematic structure-activity relationship studies.

Anti-cancer Parasporin Toxins are Associated with Different Environments: Discovery of Two Novel Parasporin 5-like Genes.

Cry toxins are primarily a family of insecticidal toxins produced by the bacterium Bacillus thuringiensis (Bt). However, some Cry toxins, called parasporins (PSs), are non-insecticidal and have been shown to differentially kill human cancer cells. Based on amino acid homology, there are currently six different classes of parasporins (PS1-6).

An expeditious green route toward 2-aryl-4-phenyl-1H-imidazoles.

Background: Azaheterocycles are an important class of compounds because of their highly potent medicinal activities, and the imidazole subcategory is of special interest in regard to drug discovery research.

Findings: An expeditious synthetic protocol of 2-aryl-4-phenyl-1H-imidazoles has been accomplished by reacting phenylglyoxal monohydrate, ammonium acetate, and aldehyde under sonication. Following this green approach a series of 2-aryl-4-phenyl-1H-imidazoles has been synthesized using diversely substituted aldehydes.

An updated h-index measures both the primary and total scientific output of a researcher.

The growing interest in scientometry stems from ethical concerns related to the proper evaluation of scientific contributions of an author working in a hard science. In the absence of a consensus, institutions may use arbitrary methods for evaluating scientists for employment and promotion. There are several indices in use that attempt to establish the most appropriate and suggestive position of any scientist in the field he/she works in.

Isolation and Characterization of the Lytic Cold-Active Bacteriophage MYSP06 from the Mingyong Glacier in China.

As unique ecological systems, glaciers are characterized by low temperatures and low nutrient levels, which allow them to be considered as “living fossils” for the purpose of researching the evolution of life and the environmental evolution of the earth. Glaciers are also natural microbial “reservoirs”. In this work, a lytic cold-active bacteriophage designated MYSP06 was isolated from Janthinobacterium sp.

Electrochemical & osteoblast adhesion study of engineered TiO2 nanotubular surfaces on titanium alloys.

TiO2 nanotubes were grafted on the surface of cpTi, Ti6Al4V and Ti6Al4V-ELI with the aim to provide a new podium for human pre-osteoblast cell (MC3T3) adhesion and proliferation. The surface morphology and chemistry of these alloys were examined with scanning electron microscopy and energy dispersive x-ray spectroscopy. TiO2 nanotubes were further characterized by cyclic potentiodynamic polarization tests and electrochemical impedance spectroscopy.

A Multiplex Real-Time PCR Assay for Screening Gypsy Moths (Lepidoptera: Erebidae) in the United States for Evidence of an Asian Genotype.

European gypsy moth populations (Lymantria dispar L.) are well established and a proven destructive force in hardwood trees throughout the United States and Canada. Introduction of the exotic Asian gypsy moth into North America would be even more impactful, as Asian gypsy moth populations have wider host ranges, and are capable of naturally dispersing more rapidly due to female flight ability.

Experimental test of host specificity in a behaviour-modifying trematode.

Host behavioural modification by parasites is a common and well-documented phenomenon. However, knowledge on the complexity and specificity of the underlying mechanisms is limited, and host specificity among manipulating parasites has rarely been experimentally verified. We tested the hypothesis that the ability to infect and manipulate host behaviour is restricted to phylogenetically closely related hosts.

Motor neurons in the escape response circuit of white shrimp (Litopenaeus setiferus).

Many decapod crustaceans perform escape tailflips with a neural circuit involving giant interneurons, a specialized fast flexor motor giant (MoG) neuron, populations of larger, less specialized fast flexor motor neurons, and fast extensor motor neurons. These escape-related neurons are well described in crayfish (Reptantia), but not in more basal decapod groups. To clarify the evolution of the escape circuit, I examined the fast flexor and fast extensor motor neurons of white shrimp (Litopenaeus setiferus; Dendrobranchiata) using backfilling.

Diagnosis and treatment of cuff tear arthropathy.

Rotator cuff tears account for a significant majority of shoulder pain presentations. Without diagnosis and management, advanced cuff tears may progress to cuff tear arthropathy, a degenerative arthritis condition of the shoulder. This article discusses the causes and management of cuff tear arthropathy, including definitive treatment with reverse shoulder arthroplasty.

Quantitative comparisons of urgent care service providers.

Purpose: The purpose of this paper is to develop, validate, and use a survey instrument to measure and compare the perceived quality of three types of US urgent care (UC) service providers: hospital emergency rooms, urgent care centres (UCC), and primary care physician offices.

Design/methodology/approach: This study develops, validates, and uses a survey instrument to measure/compare differences in perceived service quality among three types of UC service providers. Six dimensions measured the components of service quality: tangibles, professionalism, interaction, accessibility, efficiency, and technical quality.

The Use of Polystyrene Beads to Prepare Arrayed Samples of Bacillus thuringiensis for Microscopic Examination.

A common activity in the global search for useful Cry toxins is the microscopic screening of bacterial colonies for the presence of Bacillus thuringiensis. High-throughput screens require that aliquots from large numbers of colonies be arrayed on a microscopic slide. However, precisely placing a small amount of bacteria on a slide, and at a density that is useful for microscopic examination, is both difficult to achieve and time consuming.

Challenges From and Beyond Symptomatology: Stereotype Threat in Young Adults With ADHD.

Objective: Stereotype threat-faced when one confronts a personally relevant stereotype in a domain-relevant context-can significantly jeopardize individual performance in test-taking situations. Research has overlooked the potential for mental health labels to serve as bases for stereotype threat in such situations. This study examines whether ADHD, a disorder frequently serving as a basis for standardized testing accommodation, may trigger stereotype threat in testing situations.

Identification of Chemical Compounds That Inhibit the Function of Glutamyl-tRNA Synthetase from Pseudomonas aeruginosa.

Pseudomonas aeruginosa glutamyl-tRNA synthetase (GluRS) was overexpressed in Escherichia coli. Sequence analysis indicated that P. aeruginosa GluRS is a discriminating GluRS and, similar to other GluRS proteins, requires the presence of tRNA(Glu) to produce a glutamyl-AMP intermediate.

Unusual Benign Tumors of the Breast.

The purpose of this article is to describe the imaging characteristics of a variety of benign breast tumors that may be encountered in daily practice, in order to formulate an appropriate differential diagnosis and to establish concordance between the imaging and the pathologic findings, and to assist the clinician with appropriate management.