Experimental evaluation of an adaptive Joule--Thomson cooling system including silicon-microfabricated heat exchanger and microvalve components

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98726/1/JVA021005.pd

Curcumin-rich curry diet and pulmonary function in Asian older adults

10.1371/journal.pone.0051753PLoS ONE71

Chronic Obstructive Pulmonary Disease Is Associated with Low Levels of Vitamin D

Introduction: COPD patients may be at increased risk for vitamin D (25(OH)D) deficiency, but risk factors for deficiency among COPD patients have not been extensively reported. Methods: Serum 25(OH)D levels were measured by liquid chromatography double mass spectrometry in subjects aged 40–76 years from Western Norway, including 433 COPD patients (GOLD stage II-IV) and 325 controls. Levels <20 ng/mL defined deficiency. Season, sex, age, body mass index (BMI), smoking, GOLD stage, exacerbation frequency, arterial oxygen tension (PaO2), respiratory symptoms, depression (CES-D score≥16), comorbidities (Charlson score), treatment for osteoporosis, use of inhaled steroids, and total white blood count were examined for associations with 25(OH)D in both linear and logistic regression models. Results: COPD patients had an increased risk for vitamin D deficiency compared to controls after adjustment for seasonality, age, smoking and BMI. Variables associated with lower 25(OH)D levels in COPD patients were obesity ( = −6.63), current smoking ( = −4.02), GOLD stage III- IV ( = −4.71, = −5.64), and depression ( = −3.29). Summertime decreased the risk of vitamin D deficiency (OR = 0.22). Conclusion: COPD was associated with an increased risk of vitamin D deficiency, and important disease characteristics were significantly related to 25(OH)D levels

Evaluation of soil permeability from consolidation analysis based on Terzaghi’s and Biot’s theory

Proper evaluation of permeability parameters has a crucial signification in multi-scale prediction of consolidation. Drainage path is connected with the time of one-dimensional consolidation in Terzaghi’s theory and numerous later solutions. That is why the evaluation of permeability factor allows to model the settlement’s time of geological layers based on results obtained on a laboratory scale. Numerous tests show a difference of the consolidation degree obtained from one-dimensional strain course and pore pressure distribution. Evaluation of consolidation coefficient cv based on a newly proposed method allows better understanding of the basic reasons of unconventional behaviour of tested soils. Unparallel characteristics of strain and pore pressure distribution show important role of soil’s skeleton creep and its relation to permeability aspects. Solutions proposed by Biot’s theory allow analysing the different velocity of strain and pore pressure distribution. The article presents a new approximated method based on Terzaghi’s theory and evaluation of parameters which are necessary in application of Biot’s one–dimensional solution. These parameters are connected with compressibility and coefficient of permeability. The goal of presented methodological studies is comparison between permeability obtained from application of Terzaghi’s and Biot’s theory. It allows trying to explain physical reasons of differences between applied models and testing results, and improving the methodology of one–dimensional consolidations tests

Preliminary investigations of creep strain of Neogene clay from Warsaw in drained triaxial tests assisted by computed microtomography

The study concerns soil creep deformation in multistage triaxial stress tests under drained conditions. High resolution X-ray computed microtomography (XμCT) was involved in structure recognition before and after triaxial tests. Undisturbed Neogene clay samples, which are widespread in central Poland, were used in this study. XμCT was used to identify representative sample series and informed the detection and rejection of unreliable ones. Maximum deviatoric stress for in situ stress confining condition was equal 95.1 kPa. This result helped in the design of further multistage investigations. The study identified the rheological strain course, which can be broken down into three characterizations: decreasing creep strain rate, transitional constant creep velocity, and accelerating creep deformation. The study found that due to multistage creep loading, the samples were strengthened. Furthermore, there is a visibly “brittle” character of failure, which may be the consequence of the microstructure transformation as a function of time as well as collapse of voids. Due to the glacial tectonic history of the analyzed samples, the reactivation of microcracks might also serve as an explanation. The number of the various sizes of shear planes after failure is confirmed by XμCT overexposure

Geological investigations reporting in polar conditions for civil engineering at the example of the construction of research station

The methodological experience and the results of observation and research have been presented as a part of an expert geological and engineering study for the planned extension of the Henryk Arctowski Polar Station on the coast of King George Island in the South Shetland Islands in Antarctica. The object is realized in an area requiring recognition of specific geodynamic conditions. According to technical requirements coming from the conceptual design project of the station (Kurylowicz and Associates, 2015) it was necessary to adopt a non-standard research program. Engineering and geological characteristics are presented in comparison with geoenvironmental considerations. The assessment of soil and rock properties was carried out in relation to the results of observations and determinations of parameters that could be assessed in the coarse-grained soils and rocks in the area of the designed object

Hydrochemical characteristics of water in the area of Arctowski Polish Polar Station on King George Island (Southern Shetlands)

The research was carried out during Antarctic summer 2015/2016 in the region of Arctowski Polish Polar Station on King George Island (Southern Shetlands) in Admiralty Bay in Antarctica. The scope of hydrochemical studies included selected elements: temperature, pH, dry residue, general slurry, ammonium ion, nitrates, macroelements (chlorides, sulphates, magnesium, bicarbonates and carbonates, sodium, magnesium and calcium) and some microelements. Surface water and groundwater are low mineralized and do not show anthropogenic impact. The results ofphysicochemical tests have been compared with marine water chemistry and few available archival data, which allowed the assessment of water quality and the attempt to identify the groundwater flow direction

Stress-strain behaviour analysis of Middle Polish glacial tills from Warsaw (Poland) based on the interpretation of advanced field and laboratory tests

The selected parameters of the Wartanian and Odranian tills, with relation to their spatial occurrence, grain size distribution, mineralogical composition, matric suction and other physical characteristics, are presented. The assessment of the lithogenesis and stress history on the microstructure is attempted. The comparison of the compression and permeability characteristics from field and laboratory tests has been performed. Laboratory consolidation tests carried out with up to 20MPa vertical stress, revealed two yield stress values, one in the range of a couple hundreds kPa, the other in the range of a couple thousands kPa. Based on those results, the reliability of the soil preconsolidation assessment, with the use of the two different methods is discussed. The aspect of the triaxial strength reduction under the dynamic loading of diverse frequency and amplitude is raised. The research results depict a variety of possible geological-engineering characteristics, under the divergent constraints scenarios, of compression or strength weakening origin. The effects of the specialized research program will widen the possibilities of physio-mechanical and structural characterization of soils for geological-engineering purposes

Magnetic resonance imaging appearance of the brain and cervical spinal cord in an edema disease affected pig

A 7-week-old male pig was presented with signs of a central nervous system disorder. An MRI of the head and cervical spine was performed immediately after euthanasia. The MRI revealed multifocal bilaterally symmetric T2-weighted hyperintense lesions in the brain and spinal cord, likely due to a toxic metabolic process. Histopathological examination supported the MRI findings and confirmed the diagnosis of edema disease due to Shiga-like toxin produced by Escherichia coli. This is the first case published of the MRI findings in an edema disease affected pig