Taking the pulse of snowmelt: in situ sensors reveal seasonal, event and diurnal patterns of nitrate and dissolved organic matter variability in an upland forest stream

Highly resolved time series data are useful to accurately identify the timing, rate, and magnitude of solute transport in streams during hydrologically dynamic periods such as snowmelt. We used in situ optical sensors for nitrate (NO3 −) and chromophoric dissolved organic matter fluorescence (FDOM) to measure surface water concentrations at 30 min intervals over the snowmelt period (March 21–May 13, 2009) at a 40.5 hectare forested watershed at Sleepers River, Vermont. We also collected discrete samples for laboratory absorbance and fluorescence as well as δ18O–NO3 − isotopes to help interpret the drivers of variable NO3 − and FDOM concentrations measured in situ. In situ data revealed seasonal, event and diurnal patterns associated with hydrological and biogeochemical processes regulating stream NO3 − and FDOM concentrations. An observed decrease in NO3 − concentrations after peak snowmelt runoff and muted response to spring rainfall was consistent with the flushing of a limited supply of NO3 − (mainly from nitrification) from source areas in surficial soils. Stream FDOM concentrations were coupled with flow throughout the study period, suggesting a strong hydrologic control on DOM concentrations in the stream. However, higher FDOM concentrations per unit streamflow after snowmelt likely reflected a greater hydraulic connectivity of the stream to leachable DOM sources in upland soils. We also observed diurnal NO3 − variability of 1–2 μmol l−1 after snowpack ablation, presumably due to in-stream uptake prior to leafout. A comparison of NO3 − and dissolved organic carbon yields (DOC, measured by FDOM proxy) calculated from weekly discrete samples and in situ data sub-sampled daily resulted in small to moderate differences over the entire study period (−4 to 1% for NO3 − and −3 to −14% for DOC), but resulted in much larger differences for daily yields (−66 to +27% for NO3 − and −88 to +47% for DOC, respectively). Despite challenges inherent in in situ sensor deployments in harsh seasonal conditions, these data provide important insights into processes controlling NO3 − and FDOM in streams, and will be critical for evaluating the effects of climate change on snowmelt delivery to downstream ecosystems

MOMIS: Exploiting agents to support information integration

Information overloading introduced by the large amount of data that is spread over the Internet must be faced in an appropriate way. The dynamism and the uncertainty of the Internet, along with the heterogeneity of the sources of information are the two main challenges for today's technologies related to information management. In the area of information integration, this paper proposes an approach based on mobile software agents integrated in the MOMIS (Mediator envirOnment for Multiple Information Sources) infrastructure, which enables semi-automatic information integration to deal with the integration and query of multiple, heterogeneous information sources (relational, object, XML and semi-structured sources). The exploitation of mobile agents in MOMIS can significantly increase the flexibility of the system. In fact, their characteristics of autonomy and adaptability well suit the distributed and open environments, such as the Internet. The aim of this paper is to show the advantages of the introduction in the MOMIS infrastructure of intelligent and mobile software agents for the autonomous management and coordination of integration and query processing over heterogeneous data sources

Morphological and geochemical features of crater lakes in Costa Rica: an overview.

This paper describes the compositional and morphological features of the crater lakes found in the volcanoes of Rincón de La Vieja, Poás, Irazú, Congo and Tenorio volcanoes (Costa Rica). As evidenced by the distribution of the water and dissolved gas chemistry along vertical profiles, the different fluid sources feeding the lakes reflect the present status of each of the volcanic systems. The chemical features of the Caliente (Poás volcano) and Rincón crater (Rincón de la Vieja volcano) lakes are mainly dependent on i) inputs of magmatic fluids from sub-lacustrine fumaroles and ii) water-rock interaction processes. Conversely, the Irazú lake is mainly affected by the presence of CO2(H2S)-rich fluids discharged from a hydrothermal system, which masked possible magmatic fluid contributions. Rainfall and organic activity are the main factors responsible for the chemical composition of Hule, Botos, Congo and Tenorio lakes. The chemical and isotopic water composition of Botos, Irazú and Hule lakes have displayed no significant variations along the vertical profiles. In contrast, Caliente lake shows a distinctive chemical stratification, mainly involving F-, Cl- and SO4 2-. The behaviour of these compounds seems to be governed by both dissolution of highly acidic species, i.e. HF, HCl and SO2 released from the magmatic environment, and microbial activity. Despite the significant increases with depth of dissolved CO2 at Caliente and Irazú lakes, the hazard for Nyos-type gas eruptions can be considered negligible, since i) the water volumes are too small and ii) the convective heat transfer limits the CO2 recharge rate. The relatively high concentrations of dissolved CO2 measured at the maximum depth of the Hule lake are likely produced by both degradation of organic material and degassing from a deep source. The sporadic episodes of fish deaths recently observed in this lake can be associated with lake overturn processes that have favoured the rise up to the lake surface of deep, oxygen-depleted waters.Journal of limnolog

Physical exercise for bone health in men with prostate cancer receiving androgen deprivation therapy: a systematic review

PURPOSE: Androgen deprivation therapy (ADT) is a treatment used in men with prostate cancer (PCa); however it is responsible for many adverse effects, with negative impact on quality of life. ADT causes loss of bone mineral density (BMD) and skeletal muscle mass, alteration of body composition, and cognitive function, which altogether lead to increased risk of accidental falls and fractures. This systematic review analyses the effectiveness of physical exercise (PE) in preventing accidental falls and fractures and reducing the loss of BMD in men with PCa receiving ADT.METHODS: We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Library for articles between database inception and September 2, 2020. Eligible studies included randomized controlled trials (RCTs) investigating the effects of exercise on bone health in men with PCa receiving ADT.RESULTS: Nine RCTs were included. Experimental PE consisted in multicomponent programmes that involved aerobic, resistance, impact-loading exercise, and football training. None of the RCTs investigated the risk of accidental falls and fractures, while two trials reported beneficial effects of PE on lumbar spine, hip, and femoral shaft BMD. No further significant difference was detected in the outcomes investigated.CONCLUSION: Evidence of the effectiveness of PE to prevent the risk of accidental falls and fractures and BMD loss is lacking. Nevertheless, clinical guidelines recommend PE as a part of the clinical management of men with PCa receiving ADT due to its known numerous health benefits. Research should focus on PE strategies to prevent accidental falls, a clinically relevant outcome in this vulnerable population.TRIAL REGISTRATION: The study protocol was registered with International Prospective Register of Systematic Reviews (PROSPERO, number CRD 42020158444 ) on 04/28/2020

Avaliação da performance do teste de aglutinação modifica (MAT) para a detecção de anticorpos anti-Toxoplasma gondii em cães

Toxoplasmosis is a zoonosis that has been the subject of study in Brazil and worldwide. The dogs are sentinels for the infection and can carry Toxoplasma gondii in the environment. Seroepidemiological surveys of these animals are an important tool in the surveillance and control of the disease and inform decision-making in health programs. In this study the performance of the Modified Agglutination Test (MAT) in the serodiagnosis of canine toxoplasmosis is evaluated and compared to the indirect immunofluorescent-antibody test (IFAT). A sample of 157 dog sera from the county of Monte Negro, Rondônia, with 76.40% positive reactions for Toxoplasma gondii (IFAT =16) was analyzed using the MAT (=25), presenting sensitivity of 85.00% (Confidence Interval 95.00%: 79.4 - 90.60%) and specificity of 100.00%.Toxoplasmose é uma zoonose que vem sendo objeto de estudos no Brasil e em todas as partes do mundo. Os cães são considerados sentinelas da infecção, podendo carrear o agente pelo ambiente. Levantamentos soro-epidemiológicos desses animais são importantes ferramentas de vigilância e controle da doença em programas de saúde. Neste estudo a performance do Teste de Aglutinação Modificada (MAT) no sorodiagnóstico da toxoplasmose canina foi avaliado e comparado à reação de imunoflorescência indireta (RIFI). Uma amostra de 157 soros de cães do município de Monte Negro, Rondônia, com 76.40% de animais positivos ao Toxoplasma gondii (RIFI =16) foi analisado utilizando o MAT (=25) e apresentou sensibilidade de 85,00% (Intervalo de Confiança 95,00%: 79,4-90,60%) e especificidade de 100,00%

U.S. CH4 emissions from oil and gas production: Have recent large increases been detected?

Recent studies have proposed significant increases in CH4 emissions possibly from oil and gas (O&G) production, especially for the U.S. where O&G production has reached historically high levels over the past decade. In this study, we show that an ensemble of time-dependent atmospheric inversions constrained by calibrated atmospheric observations of surface CH4 mole fraction, with some including space-based retrievals of column average CH4 mole fractions, suggests that North American CH4 emissions have been flat over years spanning 2000 through 2012. Estimates of emission trends using zonal gradients of column average CH4 calculated relative to an upstream background are not easy to make due to atmospheric variability, relative insensitivity of column average CH4 to surface emissions at regional scales, and fast zonal synoptic transport. In addition, any trends in continental enhancements of column average CH4 are sensitive to how the upstream background is chosen, and model simulations imply that short-term (4 years or less) trends in column average CH4 horizontal gradients of up to 1.5 ppb/yr can occur just from interannual transport variability acting on a strong latitudinal CH4 gradient. Finally, trends in spatial gradients calculated from space-based column average CH4 can be significantly biased (>2-3 ppb/yr) due to the nonuniform and seasonally varying temporal coverage of satellite retrievals.CC-BY 4.

Post-operative acute urinary retention after greenlight laser. Analysis of risk factors from a multicentric database

Purpose: Greenlight laser is a mini-invasive technique used to treat Benign Prostatic Obstruction (BPO). Some of the advantages of GreenLight photoselective vaporization (PVP) are shorter catheterization time and hospital stay compared to TURP. Post-operative acute urinary retention (pAUR) leads to patients' discomfort, prolonged hospital stay and increased health care costs. We analyzed risk factors for urinary retention after GreenLight laser PVP. Materials and methods: In a multicenter experience, we retrospectively analyzed the onset of early and late post-operative acute urinary retention in patients undergoing standard or anatomical PVP. The pre-, intra- and post-operative characteristics were compared betweene patients who started to void and the patients who developed post-operative urinary retention. Results: The study included 434 patients suitable for the study. Post-operative acute urinary retention occurred in 39 (9%). Patients with a lower prostate volume (P < .001), an adenoma volume lower than 40 mL (P < .001), and lower lasing time (P = .013) had a higher probability to develop pAUR at the univariate analysis. The multivariate logistic regression confirmed that lower lasing time (95% CI: 0.86-0.99, OR = 0.93, P = .046) and adenoma volume (95% CI: 0.89-0.98, OR = 0.94, P = .006) are correlated to pAUR. Furthermore IPSS ≥ 19 (95% CI: 1.19- 10.75, OR = 2.27, P = .023) and treatment with 5-ARI (95% CI: 1.05-15.03, OR = 3.98, P = .042) are risk factors for pAUR. Conclusion: In our series, post-operative acute urinary retention was related to low adenoma volume and lasing time, pre-operative IPSS ≥ 19 and 5-ARI intake. These data should be considered in deciding the best timing for urethral catheters removal

Long-term disability trajectories in relapsing multiple sclerosis patients treated with early intensive or escalation treatment strategies

Background and aims: No consensus exists on how aggressively to treat relapsing-remitting multiple sclerosis (RRMS) nor on the timing of the treatment. The objective of this study was to evaluate disability trajectories in RRMS patients treated with an early intensive treatment (EIT) or with a moderate-efficacy treatment followed by escalation to higher-efficacy disease modifying therapy (ESC). Methods: RRMS patients with ⩾5-year follow-up and ⩾3 visits after disease modifying therapy (DMT) start were selected from the Italian MS Registry. EIT group included patients who received as first DMT fingolimod, natalizumab, mitoxantrone, alemtuzumab, ocrelizumab, cladribine. ESC group patients received the high efficacy DMT after ⩾1 year of glatiramer acetate, interferons, azathioprine, teriflunomide or dimethylfumarate treatment. Patients were 1:1 propensity score (PS) matched for characteristics at the first DMT. The disability trajectories were evaluated by applying a longitudinal model for repeated measures. The effect of early versus late start of high-efficacy DMT was assessed by the mean annual Expanded Disability Status Scale (EDSS) changes compared with baseline values (delta-EDSS) in EIT and ESC groups. Results: The study cohort included 2702 RRMS patients. The PS matching procedure produced 363 pairs, followed for a median (interquartile range) of 8.5 (6.5-11.7) years. Mean annual delta-EDSS values were all significantly (p < 0.02) higher in the ESC group compared with the EIT group. In particular, the mean delta-EDSS differences between the two groups tended to increase from 0.1 (0.01-0.19, p = 0.03) at 1 year to 0.30 (0.07-0.53, p = 0.009) at 5 years and to 0.67 (0.31-1.03, p = 0.0003) at 10 years. Conclusion: Our results indicate that EIT strategy is more effective than ESC strategy in controlling disability progression over time

Natalizumab, Fingolimod and Dimethyl Fumarate Use and Pregnancy-Related Relapse and Disability in Women With Multiple Sclerosis

To investigate pregnancy-related disease activity in a contemporary multiple sclerosis (MS) cohort