A Comparison of Tandem Walk Performance Between Bed Rest Subjects and Astronauts

Astronauts experience a microgravity environment during spaceflight, which results in a central reinterpretation of both vestibular and body axial-loading information by the sensorimotor system. Subjects in bed rest studies lie at 6deg head-down in strict bed rest to simulate the fluid shift and gravity-unloading of the microgravity environment. However, bed rest subjects still sense gravity in the vestibular organs. Therefore, bed rest isolates the axial-unloading component, thus allowing for the direct study of its effects. The Tandem Walk is a standard sensorimotor test of dynamic postural stability. In a previous abstract, we compared performance on a Tandem Walk test between bed rest control subjects, and short- and long-duration astronauts both before and after flight/bed rest using a composite index of performance, called the Tandem Walk Parameter (TWP), that takes into account speed, accuracy, and balance control. This new study extends the previous data set to include bed rest subjects who performed exercise countermeasures. The purpose of this study was to compare performance during the Tandem Walk test between bed rest subjects (with and without exercise), short-duration (Space Shuttle) crewmembers, and long-duration International Space Station (ISS) crewmembers at various time points during their recovery from bed rest or spaceflight

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Factors That Influence the Quality of RNA From the Pancreas of Organ Donors

Attaining high-quality RNA from the tissues or organs of deceased donors used for research can be challenging due to physiological and logistical considerations. In this investigation, METHODS: RNA Integrity Number (RIN) was determined in pancreatic samples from 236 organ donors and used to define high (≥6.5) and low (≤4.5) quality RNAs. Logistic regression was used to evaluate the potential effects of novel or established organ and donor factors on RIN. Univariate analysis revealed donor cause of death (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.15-0.77; P = 0.01), prolonged tissue storage before RNA extraction (OR, 0.65; 95% CI, 0.52-0.79; P < 0.01), pancreas region sampled (multiple comparisons, P < 0.01), and sample type (OR, 0.32; 95% CI, 0.15-0.67; P < 0.01) negatively influenced outcome. Conversely, duration of final hospitalization (OR, 3.95; 95% CI, 1.59-10.37; P < 0.01) and sample collection protocol (OR, 8.48; 95% CI, 3.96-19.30; P < 0.01) positively impacted outcome. Islet RNA obtained via laser capture microdissection improved RIN when compared with total pancreatic RNA from the same donor (ΔRIN = 1.3; 95% CI, 0.6-2.0; P < 0.01). A multivariable model demonstrates that autopsy-free and biopsy-free human pancreata received, processed, and preserved at a single center, using optimized procedures, from organ donors dying of anoxia with normal lipase levels increase the odds of obtaining high-quality RNA

Hospital time prior to death and pancreas histopathology: implications for future studies

Diabetes research studies routinely rely upon the use of tissue samples from human organ donors. It remains unclear whether the length of hospital stay prior to organ donation affects the presence of cells infiltrating the pancreas or the frequency of replicating beta cells. To address this, 39 organ donors without diabetes were matched for age, sex, BMI and ethnicity in groups of three. Within each group, donors varied by length of hospital stay immediately prior to organ donation (<3 days, 3 to <6 days, or ≥6 days). Serial sections from tissue blocks in the pancreas head, body and tail regions were immunohistochemically double stained for insulin and CD45, CD68, or Ki67. Slides were electronically scanned and quantitatively analysed for cell positivity. No differences in CD45 , CD68 , insulin , Ki67 or Ki67 /insulin cell frequencies were found when donors were grouped according to duration of hospital stay. Likewise, no interactions were observed between hospitalisation group and pancreas region, age, or both; however, with Ki67 staining, cell frequencies were greater in the body vs the tail region of the pancreas (∆ 0.65 [unadjusted 95% CI 0.25, 1.04]; p = 0.002) from donors <12 year of age. Interestingly, frequencies were less in the body vs tail region of the pancreas for both CD45 cells (∆ -0.91 [95% CI -1.71, -0.10]; p = 0.024) and insulin cells (∆ -0.72 [95% CI -1.10, -0.34]; p < 0.001). This study suggests that immune or replicating beta cell frequencies are not affected by the length of hospital stay prior to donor death in pancreases used for research. All referenced macros (adopted and developed), calculations, programming code and numerical dataset files (including individual-level donor data) are freely available on GitHub through Zenodo at https://doi.org/10.5281/zenodo.1034422

Social media use as a predictor of higher body mass index in persons living with HIV

Social media tools have been touted as an approach to bring more democratic communication to health care. We conducted a multi-site cross-sectional study among persons living with HIV (PLWH) to desrcibe technology use among PLWH in the US and the association between social media use and body-mass index (BMI). Our primary predictor variable was social media use. Our primary outcome was BMI measured through height and weight. Descriptive statistics were used to describe the demographic profiles of the study participants and linear regression models were used to analyze associations between the outcome and predictor variables controlling for demographic characteristics. Study participants (N = 606) across 6 study sites in the United States were predominately 50-74 years old (67%). Thirty-three percent of study participants had a normal weight (BMI 18.5-25), 33% were overweight (BMI 25-30), and 32% were obese (BMI &gt; 30). Participants used several social media sites with Facebook (45.6%) predominating. Social media use was associated with higher BMI in study participants (p &lt; .001) and this effect persisted, although not as strongly, when limiting the analysis to those who only those who used Facebook (p = .03). Further consideration of social factors that can be ameliorated to improve health outcomes is timely and needed

Cosmic Underground : A Grimoire of Black Speculative Discontent

"Cosmic Underground: A Grimoire of Black Speculative Discontent and its inspiration, the groundbreaking exhibition Unveiling Visions, applies a global lens and planetary vision to the black imagination, and brings this context to a wide survey of contemporary works. This book showcases illustrations, graphic design, literature, posters, and mixed-media digital and analog artworks along with insightful analysis by brilliant scholars and amazingly talented creatives. Cosmic Underground serves as a creative, experimental and educational motive force to analyze the growing corpus of work surrounding the nexus between politics and contemporary artistic production. This project includes the areas of black cultural production situated within Afrofuturism, AstroBlackness, the EthnoGothic, Magical Realism, Sword and Soul and the AfroSurreal." -- Publisher's website

Intramolekulare 1,3-dipolare Cycloadditionen von Diarylnitriliminen aus 2,5-Diaryltetrazolen

Alkenyl-substituted diaryl-nitrile-imines - generated by photolysis or thermolysis of alkenyl-substituted 2,5-diaryl-tetrazoles - undergo a regioselective intramolecular [2+3] cycloaddition to yield new heterocyclic compounds, e.g. fused 2-pyrazolines. With alkinyl derivatives, the corresponding pyrazoles have been formed. UV evidence is given for the intermediate nitrile-imine at - 190°. The latter can be trapped using an excess of carboxylic acid (UV evidence for a new intermediate at - 120°). In this case, the corresponding rearranged addition product N'-acyl-N'-aryl-benzohydrazide is isolated in good yield