Inter disciplinary approach to aquaculture - with special reference to Damdama, Haryana

Successful aquaculture development depends not only on the economic evaluation of the cost parameters involved, but also a careful consideration of various bio-socio-economic factors is required. Financial viability has to be linked with location specific technology packaging within the framework of integrated rural development

Bone turnover markers in women can predict low bone mineral density

Background: Morbidity and mortality associated with osteoporosis continues to be high in India due to late diagnosis. This study aims to find the difference in the levels of bone turn over markers in premenopausal and postmenopausal women, in order to assess whether these markers can be used as predictors of low bone mineral density which can develop in later life.Methods: Study was conducted on 350 women aged 30-65 years. Women were classified into premenopausal and postmenopausal groups based on their menstrual history. Serum samples were analyzed for osteocalcin and telopeptide-C. Student’s t-test and logistic regression are used for statistical confirmations.Results: Levels of these markers (ng/ml) were found to be lower in premenopausal women (Osteocalcin = 9.0 ± 1.0; telopeptide-C = 0.270 ± 0.099) than in postmenopausal women (Osteocalcin = 9.8 ± 1.7; telopeptide-C = 0.490 ± 0.135) and this difference was found to be significant (P <0.001) for both the markers. In both the groups, telopeptide-C made significant contribution to prediction of low BMD [(Premenopausal group - odds ratio (OR) = 2.9; 95% confidence interval (95%CI) = 1.3-6.5 and postmenopausal group - OR = 9.6; 95%CI = 6.0-13.23) but osteocalcin could not (premenopausal group - OR = 0.91; 95%CI = 0.58-1.42 and postmenopausal group - OR = 0.87; 95%CI = 0.54-1.4)]. In premenopausal women increase in telopeptide-C by a unit increased chance of developing low BMD by 2.9 times while in postmenopausal women increase in telopeptide-C by a unit increased chance of developing low BMD by 9.6 times.Conclusion: Women with higher levels of telopeptide-C need to be identified at an early stage as it provides with an early warning of the possibility of future development of osteoporosis so that preventive measures can be taken timely.

Evaluation of antidepressant and analgesic activity of tapentadol with mirtazapine: an experimental study

Background: Data comparing tapentadol with an antidepressant is limited. A comparison of tapentadol with mirtazapine at different dose has not been performed, the other antidepressant in the same therapeutic class with a significant market share, has been undertaken. In the absence of relevant data to assess the place that tapentadol should occupy in the therapeutic arsenal, indirect comparisons are the most rigorous way to go. We conducted a study evaluate antidepressant and analgesic activity of tapentadol with mirtazapine at different doses in Swiss albino mice.Methods: Tapentadol was administered at 10, 20 and 40 mg/kg (i.p) once daily for 14 days to swiss albino mice of either sex. The immobility period for antidepressant activity of mice were recorded in forced swim test and reaction time for analgesic activity of mice were recorded in tail flick test of the control and drug treated group. The antidepressant and analgesic activity of tapentadol (10, 20, 40 mg/kg i.p) was compared with that of mirtazapine (3, 5, 7 mg/kg i.p), administered for 14 days.Results: Tapentadol produced better antidepressant at (20, 40 mg/kg), but less at 10 mg/kg and significant analgesic activity at all the three doses, as indicated by reduction in immobility times and increase in reaction time as compared to control. Mirtazapine produced no antinociceptive activity at 3 mg/kg, but significant at 5, 7 mg/kg and showed better antidepressant activity at all the three doses in mice. The result of this study indicates the better analgesic activity of tapentadol at all the doses and least antidepressant activity at 10 mg/kg, as compared to mirtazapine which has shown better antidepressant activity at all the three doses but no analgesic activity at 3 mg/kg.Conclusion: It can be concluded that tapentadol is a better drug in case of depression associated with pain compared to mirtazapine in mice

Role of rainfall in the breeding of Labeo rohita (Ham.), Cirrhinus mrigala (Ham.), Catla catla (Ham.), at Damdama (Haryana), a semi-arid zone

The role of several environmental factors on the breeding and hatching of fish has been studied by many earlier investigators. Perfection in the hypophysation technique has helped to some extent in by-passing the environmental variables such as temperature, light and rain. With the use of a modern fish hatchery, it is possible to attain maximum success in breeding and hatching, even without rains; reference is given to studies carried out regarding the role of rainfall in the breeding of Labeo rohita, Cirrhinus mrigala, Catla catla

Cosmological Implications of Unimodular Gravity

We consider a model of gravity and matter fields which is invariant only under unimodular general coordinate transformations (GCT). The determinant of the metric is treated as a separate field which transforms as a scalar under unimodular GCT. Furthermore we also demand that the theory is invariant under a new global symmetry which we call generalized conformal invariance. We study the cosmological implications of the resulting theory. We show that this theory gives a fit to the high-z supernova data which is identical to the standard Big Bang model. Hence we require some other cosmological observations to test the validity of this model. We also consider some models which do not obey the generalized conformal invariance. In these models we can fit the supernova data without introducing the standard cosmological constant term. Furthermore these models introduce only one dark component and hence solve the coincidence problem of dark matter and dark energy.Comment: 18 pages, no figures, major revisions, substantial changes in analysis, results and conclusion

Increased influence of nitrogen limitation on CO₂ emissions from future land use and land use change

In the latest projections of future greenhouse gas emissions for the Intergovernmental Panel on Climate Change (IPCC), few Earth System Models included the effect of nitrogen limitation, a key process limiting forest regrowth. Few included forest management (wood harvest). We estimate the impacts of nitrogen limitation on the CO2 emissions from land use and land use change (LULUC), including wood harvest, for the period 1900–2100. We use a land surface model that includes a fully coupled carbon and nitrogen cycle and accounts for forest regrowth processes following agricultural abandonment and wood harvest. Future projections are based on the four Representation Concentration Pathways used in the IPCC Fifth Assessment Report, and we account for uncertainty in future climate for each scenario based on ensembles of climate model outputs. Results show that excluding nitrogen limitation will underestimate global LULUC emissions by 34–52 PgC (20–30%) during the 20th century (range across three different historical LULUC reconstructions) and by 128–187 PgC (90–150%) during the 21st century (range across the four IPCC scenarios). The full range for estimated LULUC emissions during the 21st century including climate model uncertainty is 91 to 227 PgC (with nitrogen limitation included). The underestimation increases with time because (1) projected annual wood harvest rates from forests summed over the 21st century are 380–1080% higher compared to those of the 20th century, resulting in more regrowing secondary forests; (2) nitrogen limitation reduces the CO2 fertilization effect on net primary production of regrowing secondary forests following wood harvest and agricultural abandonment; and (3) nitrogen limitation effect is aggravated by the gradual loss of soil nitrogen from LULUC disturbance. Our study implies that (1) nitrogen limitation of CO2 uptake is substantial and sensitive to nitrogen inputs; (2) if LULUC emissions are larger than previously estimated in studies without nitrogen limitation, then meeting the same climate mitigation target would require an equivalent additional reduction of fossil fuel emissions; (3) the effectiveness of land-basedmitigation strategies will critically depend on the interactions between nutrient limitations and secondary forests resulting from LULUC; and (4) it is important for terrestrial biosphere models to consider nitrogen constraint in estimates of the strength of future land carbon uptake.NASA (NNX14AD94G)U.S. National Science Foundation (NSF-AGS- 12-43071)U.S. Department of Energy (DOE-DE-SC0006706)Ope

Nitrogen attenuation of terrestrial carbon cycle response to global environmental factors

Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 23 (2009): GB4028, doi:10.1029/2009GB003519.Nitrogen cycle dynamics have the capacity to attenuate the magnitude of global terrestrial carbon sinks and sources driven by CO2 fertilization and changes in climate. In this study, two versions of the terrestrial carbon and nitrogen cycle components of the Integrated Science Assessment Model (ISAM) are used to evaluate how variation in nitrogen availability influences terrestrial carbon sinks and sources in response to changes over the 20th century in global environmental factors including atmospheric CO2 concentration, nitrogen inputs, temperature, precipitation and land use. The two versions of ISAM vary in their treatment of nitrogen availability: ISAM-NC has a terrestrial carbon cycle model coupled to a fully dynamic nitrogen cycle while ISAM-C has an identical carbon cycle model but nitrogen availability is always in sufficient supply. Overall, the two versions of the model estimate approximately the same amount of global mean carbon uptake over the 20th century. However, comparisons of results of ISAM-NC relative to ISAM-C reveal that nitrogen dynamics: (1) reduced the 1990s carbon sink associated with increasing atmospheric CO2 by 0.53 PgC yr−1 (1 Pg = 1015g), (2) reduced the 1990s carbon source associated with changes in temperature and precipitation of 0.34 PgC yr−1 in the 1990s, (3) an enhanced sink associated with nitrogen inputs by 0.26 PgC yr−1, and (4) enhanced the 1990s carbon source associated with changes in land use by 0.08 PgC yr−1 in the 1990s. These effects of nitrogen limitation influenced the spatial distribution of the estimated exchange of CO2 with greater sink activity in high latitudes associated with climate effects and a smaller sink of CO2 in the southeastern United States caused by N limitation associated with both CO2 fertilization and forest regrowth. These results indicate that the dynamics of nitrogen availability are important to consider in assessing the spatial distribution and temporal dynamics of terrestrial carbon sources and sinks.We also acknowledge the financial support of the National Aeronautics and Space Administration Land Cover and Land Use Change Program (NNX08AK75G)

Future atmospheric methane concentrations in the context of the stabilization of greenhouse gas concentrations

Abstract. Tropospheric CH 4 concentration depends, according to modeled tropospheric processes, on many factors, including emissions of CH 4 as well as NO x and CO. Illustrative analyses of the relation between emissions and CH 4 concentration give some guidance on the role of CH 4 in the stabilization of greenhouse gas concentrations. The contribution of CH 4 to radiative forcing at the time of stabilization is expected to be modest, provided CH 4 and CO emissions do not go far beyond current rates. However, in cases leading to stabilization the potential mitigation of increases in radiative forcing by methane control could be comparable to that of CO 2 control over the next century. Whether or not this potential is realized will depend partially on the cost of deep reductions of CH 4 , NO x , CO, or CO 2 emissions over the next century, which is not known

Hydroclimatic extremes contribute to asymmetric trends in ecosystem productivity loss

Gross primary production is the basis of global carbon uptake. Gross primary production losses are often related to hydroclimatic extremes such as droughts and heatwaves, but the trend of such losses driven by hydroclimatic extremes remains unclear. Using observationally-constrained and process-based model data from 1982-2016, we show that drought-heat events, drought-cold events, droughts and heatwaves are the dominant drivers of gross primary production loss. Losses associated with these drivers increase in northern midlatitude ecosystem but decrease in pantropical ecosystems, thereby contributing to around 70% of the variability in total gross primary production losses. These asymmetric trends are caused by an increase in the magnitude of gross primary production losses in northern midlatitudes and by a decrease in the frequency of gross primary production loss events in pantropical ecosystems. Our results suggest that the pantropics may have become less vulnerable to hydroclimatic variability over recent decades whereas gross primary production losses and hydroclimatic extremes in northern midlatitudes have become more closely entangled

Evaluation of simulated soil carbon dynamics in Arctic-Boreal ecosystems

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Huntzinger, D. N., Schaefer, K., Schwalm, C., Fisher, J. B., Hayes, D., Stofferahn, E., Carey, J., Michalak, A. M., Wei, Y., Jain, A. K., Kolus, H., Mao, J., Poulter, B., Shi, X., Tang, J., & Tian, H. Evaluation of simulated soil carbon dynamics in Arctic-Boreal ecosystems. Environmental Research Letters, 15(2), (2020): 025005, doi:10.1088/1748-9326/ab6784.Given the magnitude of soil carbon stocks in northern ecosystems, and the vulnerability of these stocks to climate warming, land surface models must accurately represent soil carbon dynamics in these regions. We evaluate soil carbon stocks and turnover rates, and the relationship between soil carbon loss with soil temperature and moisture, from an ensemble of eleven global land surface models. We focus on the region of NASA's Arctic-Boreal vulnerability experiment (ABoVE) in North America to inform data collection and model development efforts. Models exhibit an order of magnitude difference in estimates of current total soil carbon stocks, generally under- or overestimating the size of current soil carbon stocks by greater than 50 PgC. We find that a model's soil carbon stock at steady-state in 1901 is the prime driver of its soil carbon stock a hundred years later—overwhelming the effect of environmental forcing factors like climate. The greatest divergence between modeled and observed soil carbon stocks is in regions dominated by peat and permafrost soils, suggesting that models are failing to capture the frozen soil carbon dynamics of permafrost regions. Using a set of functional benchmarks to test the simulated relationship of soil respiration to both soil temperature and moisture, we find that although models capture the observed shape of the soil moisture response of respiration, almost half of the models examined show temperature sensitivities, or Q10 values, that are half of observed. Significantly, models that perform better against observational constraints of respiration or carbon stock size do not necessarily perform well in terms of their functional response to key climatic factors like changing temperature. This suggests that models may be arriving at the right result, but for the wrong reason. The results of this work can help to bridge the gap between data and models by both pointing to the need to constrain initial carbon pool sizes, as well as highlighting the importance of incorporating functional benchmarks into ongoing, mechanistic modeling activities such as those included in ABoVE.This work was supported by NASA'S Arctic Boreal Vulnerability Experiment (ABoVE; https://above.nasa.gov); NNN13D504T. Funding for the Multi-scale synthesis and Terrestrial Model Intercomparison Project (MsTMIP; https://nacp.ornl.gov/MsTMIP.shtml) activity was provided through NASA ROSES Grant #NNX10AG01A. Data management support for preparing, documenting, and distributing model driver and output data was performed by the Modeling and Synthesis Thematic Data Center at Oak Ridge National Laboratory (MAST-DC; https://nacp.ornl.gov), with funding through NASA ROSES Grant #NNH10AN681. Finalized MsTMIP data products are archived at the ORNL DAAC (https://daac.ornl.gov). We also acknowledge the modeling groups that provided results to MsTMIP. The synthesis of site-level soil respiration, temperature, and moisture data reported in Carey et al 2016a, 2016b) was funded by the US Geological Survey (USGS) John Wesley Powell Center for Analysis and Synthesis Award G13AC00193. Additional support for that work was also provided by the USGS Land Carbon Program. JBF carried out the research at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. California Institute of Technology. Government sponsorship acknowledged