Multiscale Legacy Responses of Soil Gas Concentrations to Soil Moisture and Temperature Fluctuations

The sensitivity of soil carbon dynamics to climate change is a major uncertainty in carbon cycle models. Of particular interest is the response of soil biogeochemical cycles to variability in hydroclimatic states and the related quantification of soil memory. Toward this goal, the power spectra of soil hydrologic and biogeochemical states were analyzed using measurements of soil temperature, moisture, oxygen, and carbon dioxide at two sites. Power spectra indicated multiscale power law scaling across subhourly to annual timescales. Precipitation fluctuations were most strongly expressed in the soil biogeochemical signals at monthly to annual timescales. Soil moisture and temperature fluctuations were comparable in strength at one site, while temperature was dominant at the other. The effect of soil hydrologic, thermal, and biogeochemical processes on gas concentration variability was evidenced by low spectral entropy relative to the white noise character of precipitation. A full mass balance model was unable to capture high-frequency soil temperature influence, indicating a gap in commonly used model assumptions. A linearized model was shown to capture the main features of the observed and modeled gas concentration spectra and demonstrated how the means and variances of soil moisture and temperature interact to produce the gas concentration spectra. Breakpoints in the spectra corresponded to the mean rate of gas efflux, providing a first-order estimate of the soil biogeochemical integral timescale (~1 min). These methods can be used to identify biogeochemical system dynamics to develop robust, process-based soil biogeochemistry models that capture variability in addition to long-term mean values. Plain Language Summary The ability to describe how climate change impacts soil carbon and nutrient cycles with models is a necessary tool for ecosystem management and sustainability. One difficulty in developing these predictive models is the so-called “legacy effect”—for example, one wet summer may alter the ecosystem for many years afterward. Soil data and models are used here to quantify the relative strength of short- and long-term variability of soil biogeochemical systems and how it responds to rainfall, soil moisture, and soil temperature. We found that variability in soil biogeochemistry is concentrated at longer timescales of several weeks to months and this is because the soil stores water and heat, retaining a “memory” of past rainfall and temperature. Further, this analysis offered a new perspective on the equations used in current models—models driven by soil moisture and temperature are able to capture the legacy in soil biogeochemical data

Retention of Gasification-Combustion Products by Corn

Shelled corn was dried in layers of 5.1 cm (2 in.) 10.2 cm (4 in.), and 15.2 cm (6 in.) using air heated with the exhaust from a corn-cob fueled gasification-combustion updraft furnace. The drying air entering and leaving the grain layers was sampled for particulate content to determine the percentage of total particulates trapped by the grain during drying. It was determined that an average of 25% of the total particulates in the drying air were retained by the grain. The large majority of those particulates retained were found in the bottom 5.1 cm (2 in.) of the grain layer

Validation of lay‐administered mental health assessments in a large Army National Guard cohort

To report the reliability and validity of key mental health assessments in an ongoing study of the Ohio Army National Guard (OHARNG). The 2616 OHARNG soldiers received hour‐long structured telephone surveys including the post‐traumatic stress disorder (PTSD) checklist (PCV‐C) and Patient Health Questionnaire – 9 (PHQ‐9). A subset ( N  = 500) participated in two hour clinical reappraisals, using the Clinician‐Administered PTSD Scale (CAPS) and the Structured Clinical Interview for DSM (SCID). The telephone survey assessment for PTSD and for any depressive disorder were both highly specific [92% (standard error, SE 0.01), 83% (SE 0.02)] with moderate sensitivity [54% (SE 0.09), 51% (SE 0.05)]. Other psychopathologies assessed included alcohol abuse [sensitivity 40%, (SE 0.04) and specificity 80% (SE 0.02)] and alcohol dependence [sensitivity, 60% (SE 0.05) and specificity 81% (SE 0.02)].The baseline prevalence estimates from the telephone study suggest alcohol abuse and dependence may be higher in this sample than the general population. Validity and reliability statistics suggest specific, but moderately sensitive instruments. Copyright © 2014 John Wiley & Sons, Ltd .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106694/1/mpr1416.pd

The Thermoanaerobacter Glycobiome Reveals Mechanisms of Pentose and Hexose Co-Utilization in Bacteria

Author Summary Renewable liquid fuels derived from lignocellulosic biomass could alleviate global energy shortage and climate change. Cellulose and hemicellulose are the main components of lignocellulosic biomass. Therefore, the ability to simultaneously utilize pentose and hexose (i.e., co-utilization) has been a crucial challenge for industrial microbes producing lignocellulosic biofuels. Certain thermoanaerobic bacteria demonstrate this unusual talent, but the genetic foundation and molecular mechanism of this process remain unknown. In this study, we reconstructed the structure and dynamics of the first genome-wide carbon utilization network of thermoanaerobes. This transcriptome-based co-expression network reveals that glucose, xylose, fructose, and cellobiose catabolism are each featured on distinct functional modules. Furthermore, the dynamics of the network suggests a distinct yet collaborative nature between glucose and xylose catabolism. In addition, we experimentally demonstrated that these novel network-derived features can be rationally exploited for product-yield enhancement via optimized timing and balanced loading of the carbon supply in a substrate-specific manner. Thus, the newly discovered modular and precisely regulated network elucidates unique features of thermoanaerobic glycobiomes and reveals novel perturbation strategies and targets for the enhanced thermophilic production of lignocellulosic biofuels.Yeshttp://www.plosgenetics.org/static/editorial#pee

Transient Dexmedetomidine Bolus-Induced Excessive Urination Intraoperatively in a 68-Year-Old Male

Excessive urination can be a perioperative challenge for providers due to the possibility of secondary hypernatremia. Dexmedetomidine has previously been reported by several groups to induce a polyuric-like syndrome; however, the exact mechanism in humans remains unclear. In this report, we discuss a case of intraoperative, transient dexmedetomidine bolus-induced excessive urination and suggest a potential mechanism by which this may occur in a subset of the population

Associations of adverse and protective childhood experiences with thwarted belongingness, perceived burdensomeness, and suicide risk among sexual minority men

BACKGROUND: Sexual minority men (SMM) experience higher suicidal ideation and suicide attempts than the general population. We examined the associations of adverse childhood experiences (ACES) and protective and compensatory childhood experiences (PACES) with suicidal ideation and suicide attempts in adulthood via thwarted belongingness and perceived burdensomeness among SMM. METHODS: Data are from the study, a national longitudinal cohort study of HIV-negative SMM from the 50 U.S. states and Puerto Rico. Between 2017 and 2019, participants ( = 6303) completed web-based assessments at baseline and 12-month follow-up. ACES and PACES occurring before the age of 18, and current symptoms of thwarted belongingness and perceived burdensomeness were assessed at baseline. Past-week suicidal ideation and past-year suicide attempt were assessed at follow-up. RESULTS: 424 (6.7%) participants reported past-week suicidal ideation and 123 (2.0%) reported a past-year suicide attempt. The results of our multivariate model suggest that each additional adverse childhood experience was prospectively associated with 14% higher odds of past-week suicidal ideation (AOR = 1.14, 95% CI 1.09-1.19) and 19% higher odds of past-year suicide attempt (AOR = 1.19, 95% CI 1.11-1.29). Each additional protective childhood experience was prospectively associated with 15% lower odds of past-week suicidal ideation (AOR = 0.85, 95% CI 0.81-0.90) and 11% lower odds of past-year suicide attempt (AOR = 0.89, 95% CI 0.82-0.98). Perceived burdensomeness partially mediated these prospective associations. CONCLUSION: To reduce suicide, screening and treating perceived burdensomeness among SMM with high ACES may be warranted. PACES may decrease perceived burdensomeness and associated suicide risk

Rebound HIV-1 in cerebrospinal fluid after antiviral therapy interruption is mainly clonally amplified R5 T cell-tropic virus

HIV-1 persists as a latent reservoir in people receiving suppressive antiretroviral therapy (ART). When ART is interrupted (treatment interruption/TI), rebound virus re-initiates systemic infection in the lymphoid system. During TI, HIV-1 is also detected in cerebrospinal fluid (CSF), although the source of this rebound virus is unknown. To investigate whether there is a distinct HIV-1 reservoir in the central nervous system (CNS), we compared rebound virus after TI in the blood and CSF of 11 participants. Peak rebound CSF viral loads vary and we show that high viral loads and the appearance of clonally amplified viral lineages in the CSF are correlated with the transient influx of white blood cells. We found no evidence of rebound macrophage-tropic virus in the CSF, even in one individual who had macrophage-tropic HIV-1 in the CSF pre-therapy. We propose a model in which R5 T cell-tropic virus is released from infected T cells that enter the CNS from the blood (or are resident in the CNS during therapy), with clonal amplification of infected T cells and virus replication occurring in the CNS during TI