On the nature of nano twin-induced shear band formation in a dispersion strengthened copper alloy under micro-mechanical loading.

A key challenge in metallic alloys with high ductility is understanding how microstructural inhomogeneities influence shear localization, leading to localized plastic deformation and material failure. In this study, we explore the phenomenon of shear localization in coarse-grained copper, a material traditionally regarded as having low susceptibility to such behavior. Contrary to conventional understanding, our findings reveal that microstructural inhomogeneities play a pivotal role in inducing extensive strain localization during low strain rate micro-mechanical loading.

Effects of Heat Input and Intertrack Overlap on the Microstructure and Properties of Inconel 686 Weld Overlays.

The objective of this study was to investigate how weld overlays with nickel superalloys are important for the integrity, due the high temperatures and corrosive environments that can be experienced in mineral processing environments, of mining and processing equipment. The Ni-Cr-Mo superalloy Inconel 686 overlays are fabricated through automatic gas metal arc welding with variations in arc voltage and travel speed (i.e.

Payload hardware and experimental protocol development to enable future testing of the effect of space microgravity on the resistance to gentamicin of uropathogenic Escherichia coli and its σ-deficient mutant.

Human immune response is compromised and bacteria can become more antibiotic resistant in space microgravity (MG). We report that under low-shear modeled microgravity (LSMMG), stationary-phase uropathogenic Escherichia coli (UPEC) become more resistant to gentamicin (Gm), and that this increase is dependent on the presence of σ (a transcription regulator encoded by the rpoS gene). UPEC causes urinary tract infections (UTIs), reported to afflict astronauts; Gm is a standard treatment, so these findings could impact astronaut health.

Nutritional Status Deteriorates Postoperatively Despite Preoperative Nutritional Support.

Background/aims: The aim of the current study was to assess the postoperative evolution of nutritional status and to relate it with postoperative outcomes.

Methods: Demographic, surgical and nutritional parameters were assessed 10 days preoperatively (d-10) and 30 days postoperatively (d30) in 146 patients. Risk factors responsible for perioperative (>5% between d-10 and d30) weight loss were identified.

Use of the nutritional risk score by surgeons and nutritionists.

Background: The Nutritional Risk Score (NRS) is a validated tool to identify patients who should benefit of nutritional interventions. Nutritional screening however has not yet been widely adopted by surgeons. Furthermore, the question about reliability of nutritional assessment performed by surgeons is still unanswered.

Directed evolution of an ultrastable carbonic anhydrase for highly efficient carbon capture from flue gas.

Carbonic anhydrase (CA) is one of nature's fastest enzymes and can dramatically improve the economics of carbon capture under demanding environments such as coal-fired power plants. The use of CA to accelerate carbon capture is limited by the enzyme's sensitivity to the harsh process conditions. Using directed evolution, the properties of a β-class CA from Desulfovibrio vulgaris were dramatically enhanced.

Sigma S-dependent antioxidant defense protects stationary-phase Escherichia coli against the bactericidal antibiotic gentamicin.

Stationary-phase bacteria are important in disease. The σ(s)-regulated general stress response helps them become resistant to disinfectants, but the role of σ(s) in bacterial antibiotic resistance has not been elucidated. Loss of σ(s) rendered stationary-phase Escherichia coli more sensitive to the bactericidal antibiotic gentamicin (Gm), and proteomic analysis suggested involvement of a weakened antioxidant defense.

The inhibition of MAPK potentiates the anti-angiogenic efficacy of mTOR inhibitors.

The mammalian target of rapamycin (mTOR) which is part of two functionally distinct complexes, mTORC1 and mTORC2, plays an important role in vascular endothelial cells. Indeed, the inhibition of mTOR with an allosteric inhibitor such as rapamycin reduces the growth of endothelial cell in vitro and inhibits angiogenesis in vivo. Recent studies have shown that blocking mTOR results in the activation of other prosurvival signals such as Akt or MAPK which counteract the growth inhibitory properties of mTOR inhibitors.

Targeting the JNK signaling pathway potentiates the antiproliferative efficacy of rapamycin in LS174T colon cancer cells.

Background: Targeting the mTOR signaling pathway with rapamycin in cancer therapy has been less successful than expected due in part to the removal of a negative feedback loop resulting in the over-activation of the PI3K/Akt signaling pathway. As the c-Jun N-terminal kinase (JNK) signaling pathway has been found to be a functional target of PI3K, we investigate the role of JNK in the anticancer efficacy of rapamycin.

Materials And Methods: The colon cancer cell line LS174T was treated with rapamycin and JNK phosphorylation was analyzed by Western Blot.

Bifrontal solitary fibrous tumor of the meninges.

Background: We report the case of a bifrontal solitary fibrous tumor (SFT) arising from the meninges. The points of interest in this case report are the particular imaging appearance, the immunohistochemical findings and the surgical features.

Case Description: A 53-year-old Caucasian male presented with a 1-year history of behavioral changes, attention disorders and anterograde memory disorders.

New device for high-throughput viability screening of flow biofilms.

Control of biofilms requires rapid methods to identify compounds effective against them and to isolate resistance-compromised mutants for identifying genes involved in enhanced biofilm resistance. While rapid screening methods for microtiter plate well ("static") biofilms are available, there are no methods for such screening of continuous flow biofilms ("flow biofilms"). Since the latter biofilms more closely approximate natural biofilms, development of a high-throughput (HTP) method for screening them is desirable.

Visualizing implanted tumors in mice with magnetic resonance imaging using magnetotactic bacteria.

Purpose: To determine if magnetotactic bacteria can target tumors in mice and provide positive contrast for visualization using magnetic resonance imaging.

Experimental Design: The ability of the magnetotactic bacterium, Magnetospirillum magneticum AMB-1 (referred to from here as AMB-1), to confer positive magnetic resonance imaging contrast was determined in vitro and in vivo. For the latter studies, AMB-1 were injected either i.

Extracellular mass transport considerations for space flight research concerning suspended and adherent in vitro cell cultures.

Conducting biological research in space requires consideration be given to isolating appropriate control parameters. For in vitro cell cultures, numerous environmental factors can adversely affect data interpretation. A biological response attributed to microgravity can, in theory, be explicitly correlated to a specific lack of weight or gravity-driven motion occurring to, within or around a cell.

Can genetically modified Escherichia coli with neutral buoyancy induced by gas vesicles be used as an alternative method to clinorotation for microgravity studies?

Space flight has been shown to affect various bacterial growth parameters. It is proposed that weightlessness allows the cells to remain evenly distributed, consequently altering the chemical makeup of their surrounding fluid, and hence indirectly affecting their physiological behaviour. In support of this argument, ground-based studies using clinostats to partially simulate the quiescent environment attained in microgravity have generally been successful in producing bacterial growth characteristics that mimic responses reported under actual space conditions.

Microgravity materials and life sciences research applications of digital holography.

We investigate the utility of digital holographic interferometry for analyzing gravity-dependent mass transport phenomena as applicable to materials and life science research topics. Digital holography is useful for measurement of parameters that introduce phase changes in light traversing the material of interest, such as temperature or concentration variations in an aqueous environment. We have constructed, tested, and verified a compact, portable digital holographic monitor (DHM) suitable for characterization of transparent samples.