Stress hormones and the immunological responses to heat and exercise

This review focuses on the response of "stress" hormones to heat, exercise (single or repeated bouts), and combinations of these stimuli, with particular reference to their impact upon immune function. Very hot conditions induce a typical stress response, with secretion of catecholamines and cortisol. The catecholamines induce a demargination of leukocytes, and cortisol subsequently causes cells to migrate to lymphoid tissue. Sustained exercise, even in a thermally comfortable environment, induces a larger hormonal response than moderate thermal stress. With moderate exercise, increases in leukocyte numbers are related mainly to plasma norepinephrine concentrations, but with more intense exercise epinephrine concentrations assume a major importance. As exercise continues, plasma cortisol levels also rise, inducing an influx of neutrophils from bone marrow and an efflux of other leukocyte subsets. A combination of exercise and heat stress augments both hormonal and leukocyte responses. But these changes seem to be reversed if temperatures are clamped by exercising in cold water. If a second bout of exercise is performed with an inter-test interval of 30-45 min, neither hormone concentrations nor immune responses show any great cumulative effect under temperate conditions. However, in a hot environment the second exercise bout induces a larger and more persistent neutrophilia. Training influences these various responses mainly by decreasing the stress imposed when exercising at a given absolute work-rate.     

Fabrication, microstructure, and mechanical properties of tin nanostructures

Vertically aligned, cylindrical tin nanopillars have been fabricated via an electron beam lithography and electroplating method. Characterization by a non-destructive synchrotron X-ray microdiffraction (μSXRD) technique revealed that the tin nanostructures are body-centered tetragonal and are likely single-crystalline, or consist of a few large grains. The mechanical properties of tin nanopillars with average diameters of 920 nm, 560 nm, and 350 nm were studied by uniaxial compression in a nanoindenter outfitted with a flat punch diamond tip. The results of compression tests reveal strain rate sensitivity for nanoscale tin deformation, which matches closely to the previously reported bulk tin values. However, unlike bulk, tin nanopillars exhibit size-dependent flow stresses where smaller diameter specimens exhibit greater attained strengths. The observed size-dependence matches closely to that previously reported for single-crystalline face centered cubic metals at the nanoscale. μSXRD data was used to compare the dislocation density between as-fabricated and deformed tin nanopillars. Results of this comparison suggest that there is no measurable accumulation of dislocations within deformed tin nanopillars.     

Molecular and Functional Imaging for Detection of Lymph Node Metastases in Prostate Cancer

Knowledge on lymph node metastases is crucial for the prognosis and treatment of prostate cancer patients. Conventional anatomic imaging often fails to differentiate benign from metastatic lymph nodes. Pelvic lymph node dissection is an invasive technique and underestimates the extent of lymph node metastases. Therefore, there is a need for more accurate non-invasive diagnostic techniques. Molecular and functional imaging has been subject of research for the last decades, in this respect. Therefore, in this article the value of imaging techniques to detect lymph node metastases is reviewed. These techniques include scintigraphy, sentinel node imaging, positron emission tomography/computed tomography (PET/CT), diffusion weighted magnetic resonance imaging (DWI MRI) and magnetic resonance lymphography (MRL). Knowledge on pathway and size of lymph node metastases has increased with molecular and functional imaging. Furthermore, improved detection and localization of lymph node metastases will enable (focal) treatment of the positive nodes only.     

Bell prover — calibration and monitoring of time stability

This paper is focused on the calibration and measurement of the geometric parameters of a bell prover that serves as a standard of volume of gas flow. It also includes methods for monitoring the time stability of the bell prover: intra- and inter-laboratory comparison measurements, Shewhart analysis and planned evaluation of recalibration intervals.     

Fabrication,structure and mechanical properties of indium nanopillars

Solid and hollow cylindrical indium pillars with nanoscale diameters were prepared using electron beam lithography followed by the electroplating fabrication method. The microstructure of the solid-core indium pillars was characterized by scanning micro-X-ray diffraction, which shows that the indium pillars were annealed at room temperature with very few dislocations remaining in the samples. The mechanical properties of the solid pillars were characterized using a uniaxial microcompression technique, which demonstrated that the engineering yield stress is ～9 times greater than bulk and is ～1/28 of the indium shear modulus, suggesting that the attained stresses are close to theoretical strength. Microcompression of hollow indium nanopillars showed evidence of brittle fracture. This may suggest that the failure mode for one of the most ductile metals can become brittle when the feature size is sufficiently small.     

Bright Surface‐Enhanced Raman Scattering with Fluorescence Quenching from Silica Encapsulated J‐Aggregate Coated Gold Nanoparticles

Plexitonic nanoparticles offer variable optical properties through tunable excitations, in addition to electric field enhancements that far exceed molecular resonators. This study demonstrates a way to design an ultrabright surface‐enhanced Raman spectroscopy (SERS) signal while simultaneously quenching the fluorescence background through silica encapsulation of the semiconductor–metal composite nanoparticles. Using a multistep approach, a J‐aggregate‐forming organic dye is assembled on the surface of gold nanoparticles using a cationic linker. Excitonic resonance of the J‐aggregate–metal system shows an enhanced SERS signal at an appropriate excitation wavelength. Further encapsulation of the decorated particles in silica shows a significant reduction in the fluorescence signal of the Raman spectra (5× reduction) and an increase in Raman scattering (7× enhancement) when compared to phospholipid encapsulation. This reduction in fluorescence is important for maximizing the useful SERS enhancement from the particle, which shows a signal increase on the order of 10⁴ times greater than J‐aggregated dye in solution and 24 times greater than Oxonica S421 SERS tag. The silica layer also serves to promote colloidal stability. The combination of reduced fluorescence background, enhanced SERS intensity, and temporal stability makes these particles highly distinguishable with potential to enable high‐throughput applications such as SERS flow cytometry.     

Mixed solid papillary and mucinous carcinoma of the breast

Reduced rapid-eye-movement (REM) sleep latency and increased REM sleep activity are associated not only with increased risk of recurrent depressive episodes but also with shortened time to the onset of subsequent episodes. Increased REM sleep activity might be a sign of attempt to excite the photic-responsive brain regions during the night, and there is a negative correlation between regional blood flow in the dorsolateral prefrontal cortex and REM sleep. The relative deactivation of the dorsolateral prefrontal cortex as a result of a developmental abnormality could explain the increased REM sleep activity during the first half of the night and the subsequent terminal insomnia among depressed subjects.