Shock vaporization/devolatilization of evaporitic minerals, halite and gypsum, in an open system investigated by a two-stage light gas gun

Dry lakebeds might constitute large volatile reservoirs on Mars. Hypervelocity impacts onto ancient dry lakebeds would have affected the volatile distribution on Mars. We developed a new experimental method to investigate the response of evaporitic minerals (halite and gypsum) to impact shocks in an open system. This technique does not result in chemical contamination from the operation of the gas gun. The technique is termed the two-valve method and the gun system is located in the Planetary Exploration Research Center, Chiba Institute of Technology, Japan. We detected the vaporization of halite at 31 GPa and devolatilization from gypsum at 11 GPa, suggesting that impact-induced volatile release from dry lakebeds has periodically occurred throughout Martian history. The vaporization of halite deposits might have enhanced the production of perchlorates, which are found globally on Mars. The water loss from gypsum possibly explains the coexisting types of Ca-sulfates found in Gale Crater.Comment: 17 pages, 4 figures, 1 supporting information, accepted for publication in Geophysical Research Letter

Skeletal muscle function and vitamin D

Age-related changes in muscle strength and physical functions, and the association between vitamin D status and skeletal muscle functions were investigated in 36 men (21-90 years old) and 52 women (21-104 years old). Significant ageing-related decreases in several skeletal muscle functions and serum 25-hydroxyvitamin D [25(OH)D] levels were observed in both men and women. Cut-off values for the Timed up and go (TUG) test, walking speed, handgrip strength and Barthel Index (BI) detecting walking difficulties in the receiver operating characteristic (ROC) analysis were 11.1 sec, 0.60 m / sec, 17.0 kg, and 90.0 in males, and 28.6 sec, 0.43 m / sec, 13.9 kg, and 67.5 in females, respectively. By comparing personal present data of muscle strength with these cut-off values, people can easily understand their process to walking difficulty. Therefore, these results are important and useful to avoid or to delay a handicapped and dependent status by improving the vitamin D level, rehabilitation and nursing care

Skeletal muscle mass and vitamin D

A clearer understanding of skeletal muscle mass (SMM) in middle-aged and elderly individuals is important for maintaining functionality. In the present study, age-related changes in SMM, the threshold of SMM with walking difficulty, intestinal nutrient absorption rate, and various serum factors were examined in Japanese populations of different ages. We used 24-h creatinine excretion as a measure of total body SMM. Age-related decreases in SMM, intestinal nutrient absorption rates, and serum 25-hydroxyvitamin D [25(OH)D] concentrations were significantly higher in women than in men. The cut-off values for SMM (kg), its percentage of total body weight (BW), the SMM index [SMMI] (Kg / m2), and creatinine height index (CHI) (%) in elderly individuals with walking difficulty were approximately 8-10 kg, 17-20% of BW, 3.9-4.6 kg / m2, and 44%, respectively. Serum 25(OH)D concentrations were closely associated with SMM (kg, % of BW, kg / m2) and CHI (%) as well as the intestinal absorption rates of nitrogen (%) and phosphorus (%) in women, but not in men. The present results demonstrate that vitamin D is an important metabolic factor in skeletal muscle, and contributes to the optimal management of skeletal muscle and the prevention of sarcopenia

Environmental and vegetational changes recorded in sedimentary leaf wax n-alkanes across the Cretaceous-Paleogene boundary at Loma Capiro, Central Cuba

金沢大学理工研究域自然システム学系The stable carbon isotopic compositions (δ13C) and chain-length distribution [ACL and n-C31/(n-C29+n-C31)] of sedimentary leaf wax n-alkanes were investigated across the Cretaceous-Paleogene (K-Pg) boundary at Loma Capiro, Central Cuba, to reconstruct paleoenvironmental changes that are recorded in terrestrial higher plants. The stratigraphic profiles of the n-alkane δ13C values show a negative excursion in the lowermost Paleocene, although its magnitude is much smaller (~0.3‰) than the global signals (1.5 to 2.0‰) in the surface ocean-atmospheric carbon reservoir. Relations between the n-alkane δ13C values and the C31/(C29+C31) ratios exhibit two different trends, suggesting that our δ13C records are likely affected by two types of paleoenvironmental factors in addition to the δ13C variations in the exogenous carbon reservoir. Rare occurrence of terrigenous organic matter that is usually transported by rivers suggests that the n-alkanes at Loma Capiro are likely to have been transported by trade winds, which recorded paleoenvironmental conditions of the northwestern part of the African continent. The n-alkane δ13C values show a parallel decrease with the ACL and C31/(C29+C31) values in the first 37,000yr following the K-Pg boundary. Such decreases are consistent with plant physiological responses to reduced net evaporation, suggesting a possible influence of the impact-induced warm-humid condition in the early Paleocene. In contrast, the n-alkane δ13C values are negatively correlated with the C31/(C29+C31) ratios from 40,000 to 67,000yr after the K-Pg boundary. This time period matches well with that required for the recovery of terrestrial floras from the K-Pg mass extinction to those with diversity equivalent to the late Cretaceous, suggesting that the n-alkane signals are also likely affected by the plant diversification process after the mass extinction. © 2010 Elsevier B.V

A Clinical Trial Evaluating the Usefulness of Tailored Antimicrobial Prophylaxis Using Rectal-culture Screening Media Prior to Transrectal Prostate Biopsy: A Multicenter, Randomized Controlled Trial

The aim of this report is to introduce an on-going, multicenter, randomized controlled trial to evaluate whether tailored antimicrobial prophylaxis guided by rectal culture screening prevents acute bacterial prostatitis following transrectal prostate biopsy (TRPB). Patients will be randomized into an intervention or non-intervention group; tazobactam-piperacillin or levofloxacin will be prophylactically administered according to the results of rectal culture prior to TRPB in the intervention group whereas levofloxacin will be routinely given in the non-intervention group. The primary endpoint is the occurrence rate of acute bacterial prostatitis after TRPB. Recruitment begins in April, 2021 and the target total sample size is 5,100 participants

Chronic expanding hematoma in the chest: A case report

Chronic expanding hematoma (CEH) is a rare disease that is usually present as a large solitary pulmonary nodule. CEHs are slow growing, but processes underlying their development remain unknown. The present study herein reports the case of a 76‑year‑old male patient with CEH and discusses a number of CEH cases published in the literature. The majority of these previously described patients were Asians. The CEH in the present case was not a successfully resected one, but the patient\u27s clinical course provided information concerning the natural history of the disease. During the clinical course, the patient underwent several chest computed tomography scans. For the present case report, the doubling time and volume change of the mass was calculated, which revealed that the lesion had an inconstant growth rate and that its onset was between 8.2‑11.0 years before the patient succumbed to this disease. Accumulation of knowledge about this rare disease will help to elucidate it further