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1.
Sci Total Environ ; 931: 172942, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38719032

ABSTRACT

Biochar is increasingly used in climate-smart agriculture, yet its impact on greenhouse gas (GHG) emissions and soil carbon (C) sequestration remains poorly understood. This study examined biochar-mediated changes in soil properties and their contribution to C stabilization and GHG mitigation by evaluating four types of biochar. Soil carbon dioxide (CO2) and nitrous oxide (N2O) emissions, soil chemical and biological properties, and soil organic carbon (SOC) mineralization kinetics were monitored using greenhouse, laboratory, and modeling experiments. Three pine wood biochars pyrolyzed at 460 °C (PB-460), 500 °C (PB-500), 700 °C (PB-700), and one pine bark biochar from gasification at 760 °C (GB-760) were added into soil at 1 % w/w basis. Soils amended with biochar were used to cultivate sorghum for three months in a greenhouse, followed by three months of laboratory incubation. Data obtained from laboratory incubation was modeled using various statistical approaches. The PB-500 and PB-700 reduced cumulative N2O-N emissions by 68.5 % and 73.9 % and CO2 equivalent C emissions by 66.9 % and 72.4 %, respectively, compared to unamended control. The N2O emissions were positively associated with soil nitrate N, available P, and biochar ash content while negatively associated with SOC. The CO2 emission was negatively related to biochar C:N ratio and volatile matter content. Biochar amended soils had 49.2 % (PB-500) to 87.7 % (PB-700) greater SOC and 22.9 % (PB-700) to 48.1 % (GB-760) greater sorghum yield than the control. While PB-700 had more saprophytes than the control, the GB-760 yielded a greater yield than biochars prepared by pyrolysis. Microbial biomass C was 7.23 to 23.3 % greater in biochar amended soils than in control. The double exponential decay model best explained the dynamics of C mineralization, which was associated with initial soil nitrate N and available P positively and total fungi and protozoa biomass negatively. Biochar amendment could be a climate smart agricultural strategy. Pyrolysis pine wood biochar showed the greatest potential to reduce GHG emissions and enhance SOC storage and stability, and gasification biochar contributed more to SOC storage and increased crop yield.


Subject(s)
Carbon , Charcoal , Greenhouse Gases , Soil , Charcoal/chemistry , Soil/chemistry , Greenhouse Gases/analysis , Carbon/analysis , Forests , Carbon Sequestration , Nitrous Oxide/analysis , Carbon Dioxide/analysis , Agriculture/methods , Air Pollutants/analysis
2.
Heliyon ; 10(6): e27904, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38524585

ABSTRACT

Energy and carbon (C) footprints of agricultural production practices have garnered high attention due to rising energy costs and increasing global warming. However, the contribution of conservation and regenerative farming practices, including cover cropping, on energy and C footprints have not yet been documented for cropping systems in arid and semi-arid regions. This study evaluated the energy and C footprint of cover crop integrated silage maize (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) production systems in the semi-arid region of the southwestern US. The treatments were mixtures of winter cover crops: i) grasses and legumes (GL), ii) grasses, brassicas, and legumes (GBL), iii) grasses and brassicas (GB), and iv) no cover crops (NCC) control for each crop production system. Results showed cover crops had 24.1-24.5% greater energy input than NCC. In silage maize rotation, energy output was 17-22% greater in GBL and GL than in NCC. In silage sorghum rotation, the energy output was 15-24% greater in all cover crops than in NCC. The resulting net energy was 16-21% greater in GBL and GL than in NCC under silage maize, while it was 18-24% greater in GBL and GB than in NCC under silage sorghum. In the silage maize system, the C-footprint per kg yield was not different among treatments, whereas in silage sorghum, it was 58% greater in GBL than in NCC. The benefit-to-cost ratio was greater than one for all treatments, but the additional revenue through C credit programs could make cover cropping a more feasible and beneficial approach, improving economic and environmental sustainability while producing silage crops. While the C footprint was crop rotation specific, cover cropping should be encouraged over crop-fallow systems to producers in semi-arid environments to reduce energy usage and increase C-credit benefits. Clear national and state policy on the C credit program will also enhance economic and environmental benefits by adopting cover cropping and other regenerative farming practices.

3.
Sci Rep ; 13(1): 21503, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38057376

ABSTRACT

The frequency, severity, and extent of climate extremes in future will have an impact on human well-being, ecosystems, and the effectiveness of emissions mitigation and carbon sequestration strategies. The specific objectives of this study were to downscale climate data for US weather stations and analyze future trends in meteorological drought and temperature extremes over continental United States (CONUS). We used data from 4161 weather stations across the CONUS to downscale future precipitation projections from three Earth System Models (ESMs) participating in the Coupled Model Intercomparison Project Phase Six (CMIP6), specifically for the high emission scenario SSP5 8.5. Comparing historic observations with climate model projections revealed a significant bias in total annual precipitation days and total precipitation amounts. The average number of annual precipitation days across CONUS was projected to be 205 ± 26, 184 ± 33, and 181 ± 25 days in the BCC, CanESM, and UKESM models, respectively, compared to 91 ± 24 days in the observed data. Analyzing the duration of drought periods in different ecoregions of CONUS showed an increase in the number of drought months in the future (2023-2052) compared to the historical period (1989-2018). The analysis of precipitation and temperature changes in various ecoregions of CONUS revealed an increased frequency of droughts in the future, along with longer durations of warm spells. Eastern temperate forests and the Great Plains, which encompass the majority of CONUS agricultural lands, are projected to experience higher drought counts in the future. Drought projections show an increasing trend in future drought occurrences due to rising temperatures and changes in precipitation patterns. Our high-resolution climate projections can inform policy makers about the hotspots and their anticipated future trajectories.

4.
Sci Rep ; 12(1): 12386, 2022 07 20.
Article in English | MEDLINE | ID: mdl-35859052

ABSTRACT

Climate smart agriculture has been emphasized for mitigating anthropogenic greenhouse gas (GHG) emissions, yet the mitigation potential of individual management practices remain largely unexplored in semi-arid cropping systems. This study evaluated the effects of different winter cover crop mixtures on CO2 and N2O emissions, net GHG balance (GHGnet), greenhouse gas intensity (GHGI), yield-scaled GHG emissions, and soil properties in irrigated forage corn (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) rotations. Four cover crop treatments: (1) grasses, brassicas, and legumes mixture (GBL), (2) grasses and brassicas mixture (GB), (3) grasses and legumes mixture (GL), and (4) a no-cover crop (NCC) control, each replicated four times under corn and sorghum phase of the rotations, were tested in the semi-arid Southern Great Plains of USA. Results showed 5-10 times higher soil respiration with cover crop mixtures than NCC during the cover crop phase and no difference during the cash crop phase. The average N2O-N emission in NCC was 44% lower than GL and 77% lower than GBL in corn and sorghum rotations. Cash crop yield was 13-30% greater in cover crop treatments than NCC, but treatment effects were not observed for GHGnet, yield-scaled emissions, and GHGI. Integrating cover crops could be a climate smart strategy for forage production in irrigated semi-arid agroecosystems.


Subject(s)
Greenhouse Gases , Agriculture/methods , Crops, Agricultural , Greenhouse Gases/analysis , Nitrous Oxide/analysis , Soil , Zea mays
5.
SAGE Open Med Case Rep ; 9: 2050313X211031332, 2021.
Article in English | MEDLINE | ID: mdl-34285806

ABSTRACT

There can be various causes of facial palsy, and sometimes the cause remains unidentified (Bell's palsy). Among the various causes of facial palsy, trauma is a major one. Depending on the severity of paralysis, traumatic facial palsy can be medically managed using corticosteroid and eye care or with surgical decompression. In selective cases with incomplete facial palsy, radio-imaging studies may not always be required. We present the case of a 13-year-old boy who presented to the primary-level hospital with a complaint of facial palsy following minor trauma to the face (slapped over the face by a friend). His Sunnybrook Score was 63/100. We managed him with prednisolone (1 mg/kg/day) for 2 weeks and then tapered, and with eye care with artificial tears for 6 weeks. There was a complete resolution of symptoms in 6 weeks. Incomplete facial paralysis due to trauma to the face can be managed medically with corticosteroids and proper eye care with artificial tears.

6.
PeerJ ; 8: e10199, 2020.
Article in English | MEDLINE | ID: mdl-33150087

ABSTRACT

Recent interest in improving soil health and agricultural sustainability recognizes the value of soil organic carbon (SOC) sequestration and nutrient cycling. The main goal of this study was to evaluate the response of various SOC and nitrogen (N) components in semiarid cropping systems transitioning from limited-irrigation to dryland and a restored grassland in the Southern High Plains of USA. Cropping systems evaluated include dryland winter wheat (Triticum aestivum L.)-sorghum (Sorghum bicolor L.)-fallow with conventional tillage (DLCTF) and no-tillage (DLNTF), limited-irrigation winter wheat-sorghum-fallow with no-tillage and cover cropping (LINTC) and no-tillage fallow (LINTF), and an undisturbed grassland (NG). Soil samples were collected from 0-15 cm and 15-30 cm depths and analyzed for SOC, total N, inorganic N, and soil microbial biomass carbon (SMBC) contents. The CO2 and N2O release during a eight-weeks long laboratory incubation were also analyzed. Results show 14% and 13% reduction in SOC and total N from 0-30 cm depth with the transition from limited-irrigation to dryland cropping systems while 51% more SOC and 41% more total N with the transition to grassland. The SMBC was 42% less in dryland cropping systems and 100% more in NG than the limited-irrigation cropping systems. However, the grassland was N limited, with 93% less inorganic N in NG compared to only 11% less in dryland cropping systems than in limited-irrigation cropping systems. The microbial respiration measured as CO2-C was highest in NG, followed by limited-irrigation and dryland cropping systems. The N2O-N release showed the lowest rate of N loss from dryland cropping systems, followed by NG and limited-irrigation cropping systems. This study demonstrated loss of SOC and N in agroecosystems transitioned to dryland crop-fallow systems, with greater magnitude of change observed in the biologically active fraction of soil organic matter. Grassland restoration could be an important strategy to increase SOC and nutrients in hot, dry, semiarid agroecosystems transitioning to dryland.

7.
BMC Emerg Med ; 20(1): 43, 2020 05 26.
Article in English | MEDLINE | ID: mdl-32456665

ABSTRACT

BACKGROUND: Sepsis is a common problem encountered in the emergency room which needs to be intervened early. Predicting prognosis is always a difficult task in busy emergency rooms using present scores, which has several variables to calculate. Red cell distribution width (RDW) is an easy, cheap, and efficacious score to predict the severity and mortality of patients with sepsis. METHODS: This prospective analytical study was conducted in the emergency room of Tribhuvan University Teaching Hospital among the patients age ≥ 16 years and with a clinical diagnosis of sepsis using qSOFA score. 148 patients were analyzed in the study by using a non-probability purposive sampling method. RESULTS: RDW has fair efficacy to predict the mortality in sepsis (Area under the Curve of 0.734; 95% C. I = 0.649-0.818; p-value = 0.000) as APACHE II (AUC of 0.728; 95% C. I = 0.637 to 0.819; p-value = 0.000) or SOFA (AUC of 0.680, 95% C. I = 0.591-0.770; p-value = 0.001). Youden Index was maximum (37%) at RDW value 14.75, which has a sensitivity of 83% (positive likelihood ratio = 1.81) and specificity of 54% (negative likelihood ratio = 0.32). Out of 44 patients with septic shock 16 died (36.4%) and among 104 patients without septic shock, 24 died (22.9%) which had the odds ratio of 0.713 (p = 0.555, 95% C. I = 0.231-2.194). Overall mortality was 27.02% (n = 40). RDW group analysis showed no mortality in RDW < 13.1 group, 3.6% mortality in 13.1 to 14 RDW group, 22.0% mortality in 14 to > 15.6 RDW group and 45.9% mortality in > 15.6 RDW group. Significant mortality difference was seen in 14 to > 15.6 and > 15.6 RDW subgroups with a p-value of 0.003 and 0.008 respectively. CONCLUSION: Area under the curve value for RDW is fair enough to predict the mortality of patients with sepsis in the emergency room. It can be integrated with other severity scores (APACHE II or SOFA score) for better prediction of prognosis of septic patients.


Subject(s)
Emergency Service, Hospital , Erythrocyte Indices , Organ Dysfunction Scores , Sepsis/blood , Sepsis/mortality , Adult , Aged , Female , Hospital Mortality , Humans , Male , Middle Aged , Nepal/epidemiology , Predictive Value of Tests , Prognosis , Prospective Studies , Sensitivity and Specificity , Tertiary Care Centers
8.
Case Rep Obstet Gynecol ; 2020: 6837961, 2020.
Article in English | MEDLINE | ID: mdl-32257475

ABSTRACT

Uterine inversion secondary to uterine pathology is a rare scenario that a gynecologist encounters. Unlike puerperal uterine inversion, it is misleading and may not always be possible to reduce to normal position without surgery. We report a case of a 35-year female with per vaginal bleeding for fifteen months with a mass-like sensation in the vaginal canal. She presented in shock and had a globular mass in the vaginal canal with the indistinct cervical os. She was resuscitated with blood transfusions and intravenous fluid. She was posted for emergency surgery where myomectomy was done vaginally, and finally, Haultain's procedure was carried out. The uterus was preserved.

9.
J Environ Public Health ; 2020: 9436068, 2020.
Article in English | MEDLINE | ID: mdl-33488740

ABSTRACT

Background: Workplace is associated with exposure to various products, which can be associated with adverse health outcomes. It is true with underground construction work. This study calculated the prevalence of common health problems among Nepalese underground construction workers in comparison to heavy construction workers. This type of study is rare in the context of Nepal and other developing countries, and we hope that the findings will help to take precautions for the prevention of these conditions. Method: It was a retrospective study based on the clinical record of outpatient cases and general health checkups of all Nepalese workers available at the Project clinic, Upper Tamakoshi Hydroelectric Project, Gongar, Bigu, Dolakha. We studied three hundred and ninety-eight workers. We used multipurpose analysis and conducted the Chi-square test and calculated correlations and odds ratios. Results: Two hundred and sixteen (54.3%) participants worked inside the tunnel, and 182 (43.2%) participants worked outside the tunnel. Respiratory disease, mainly upper respiratory tract infection (URTI) (23.4%), is the most common presentation among construction workers followed by injuries (16.7%). Injuries and hypertension were significantly higher in inside the tunnel workers, and acute gastroenteritis was significantly (p value <0.05) higher in outside the tunnel workers. Increasing age increased the chance of hypertension and cutaneous fungal infection among construction workers. Further studies are required for the analysis of risk factors associated with these health conditions. Conclusion: Respiratory problems are the most common health problem in underground construction workers; however, injuries and hypertension were significantly higher in tunnel workers. Acute gastroenteritis was significantly higher among outside the tunnel workers. Workplace safety should be the priority of every construction site, especially focusing to prevent respiratory problems, injuries, and accidents.


Subject(s)
Construction Industry/statistics & numerical data , Dermatomycoses/epidemiology , Gastroenteritis/epidemiology , Hypertension/epidemiology , Occupational Health/statistics & numerical data , Respiratory Tract Infections/epidemiology , Wounds and Injuries/epidemiology , Acute Disease/epidemiology , Age Factors , Nepal/epidemiology , Prevalence , Retrospective Studies , Risk Factors , Workplace
10.
Sci Rep ; 9(1): 12151, 2019 08 21.
Article in English | MEDLINE | ID: mdl-31434925

ABSTRACT

Soil organic carbon (SOC) is integral to soil health and agroecosystem resilience. Despite much research, understanding of temperature sensitivity of SOC under long-term agricultural management is very limited. The main objective of this study was to evaluate SOC and nitrogen (N) dynamics under grasslands and winter wheat (Triticum aestivum L)-based crop rotations in the inland Pacific Northwest (IPNW), USA, and measure SOC mineralization under ambient and elevated incubation temperatures. Soil samples were collected from 0-10 and 10-20 cm depths from an undisturbed grassland (GP), winter wheat-pea (Pisum sativum L) rotations under conventional tillage (WP-CT) and no-tillage (WP-NT), and winter wheat-fallow rotation under conventional tillage (WF-CT) and analyzed for SOC and N pools. Soil samples were incubated at 20 °C and 30 °C for 10 weeks, and SOC mineralization rates were estimated using the first order kinetic model. The GP had the greatest amounts of SOC, total N (TN), and microbial biomass carbon (MBC) and WP rotations had higher inorganic N content than other treatments. The SOC mineralization at elevated incubation temperature was 72-177% more than at the ambient temperature, and the greatest effect was observed in GP. The SOC storage under a given management did not have consistent effects on soil carbon (C) and N mineralization under elevated temperature. However, soil disturbance under WP-CT and WF-CT accelerated SOC mineralization leading to soil C loss. Reducing tillage, integrating legumes into crop rotations, and growing perennial grasses could minimize SOC loss and have the potential to improve soil health and agroecosystem resilience under projected climate warming.

11.
JNMA J Nepal Med Assoc ; 56(212): 796-799, 2018.
Article in English | MEDLINE | ID: mdl-30387472

ABSTRACT

INTRODUCTION: Breech delivery has always been matter of interest in obstetrics. Cesarean breech delivery has been preferred method of delivery. We aim to find out any differences in outcome between vaginal breech delivery and cesarean breech delivery in our setup. METHODS: Data were collected from record book of Department of Gynaecology and obstetrics, Pokhara Academy of Health Sciences, Kaski, Nepal. Pregnant with breech presentation who had delivery in the centre from 2074 Baishak to 2074 chaitra were enrolled in the study. Data of 174 patients were analysed among which 74 underwent vaginal delivery for breech and 110 underwent cesarean breech delivery. RESULTS: Only 1 (1.6%) of newborn delivered by vaginal route were admitted to NCU vs 17 (15.5% )in cesarean group which was significant (odds ratio= 0.071, 95% C.I 0.009-0.574; p= 0.004). There was only one death of newborn which was delivered by vaginal route. Mean APGAR score at 1 and 5 minute in vaginal breech delivery was 6 and 7 and in cesarean breech delivery was 6 and 8. CONCLUSIONS: Though perinatal morbidity was more with cesarean breech delivery but further study with more sample size is needed before reaching conclusion.


Subject(s)
Breech Presentation/epidemiology , Cesarean Section/statistics & numerical data , Delivery, Obstetric/statistics & numerical data , Tertiary Care Centers/statistics & numerical data , Adult , Age Factors , Apgar Score , Cross-Sectional Studies , Female , Gestational Age , Humans , Infant, Newborn , Nepal/epidemiology , Parity , Pregnancy , Pregnancy Outcome , Young Adult
12.
PLoS One ; 13(4): e0195782, 2018.
Article in English | MEDLINE | ID: mdl-29672548

ABSTRACT

External inputs to agricultural systems can overcome latent soil and climate constraints on production, while contributing to greenhouse gas emissions from fertilizer and water management inefficiencies. Proper crop selection for a given region can lessen the need for irrigation and timing of N fertilizer application with crop N demand can potentially reduce N2O emissions and increase N use efficiency while reducing residual soil N and N leaching. However, increased variability in precipitation is an expectation of climate change and makes predicting biomass and gas flux responses to management more challenging. We used the DayCent model to test hypotheses about input intensity controls on sorghum (Sorghum bicolor (L.) Moench) productivity and greenhouse gas emissions in the southwestern United States under future climate. Sorghum had been previously parameterized for DayCent, but an inverse-modeling via parameter estimation method significantly improved model validation to field data. Aboveground production and N2O flux were more responsive to N additions than irrigation, but simulations with future climate produced lower values for sorghum than current climate. We found positive interactions between irrigation at increased N application for N2O and CO2 fluxes. Extremes in sorghum production under future climate were a function of biomass accumulation trajectories related to daily soil water and mineral N. Root C inputs correlated with soil organic C pools, but overall soil C declined at the decadal scale under current weather while modest gains were simulated under future weather. Scaling biomass and N2O fluxes by unit N and water input revealed that sorghum can be productive without irrigation, and the effect of irrigating crops is difficult to forecast when precipitation is variable within the growing season. These simulation results demonstrate the importance of understanding sorghum production and greenhouse gas emissions at daily scales when assessing annual and decadal-scale management decisions' effects on aspects of arid and semiarid agroecosystem biogeochemistry.


Subject(s)
Climate , Nitrogen , Soil/chemistry , Sorghum/growth & development , Water , Agricultural Irrigation , Biomass , Carbon , Fertilizers , Models, Theoretical , New Mexico , Nitrous Oxide/analysis , Weather
13.
PLoS One ; 9(8): e103901, 2014.
Article in English | MEDLINE | ID: mdl-25090235

ABSTRACT

Changes in soil microbiotic properties such as microbial biomass and community structure in response to alternative management systems are driven by microbial substrate quality and substrate utilization. We evaluated irrigated crop and forage production in two separate four-year experiments for differences in microbial substrate quality, microbial biomass and community structure, and microbial substrate utilization under conventional, organic, and reduced-tillage management systems. The six different management systems were imposed on fields previously under long-term, intensively tilled maize production. Soils under crop and forage production responded to conversion from monocropping to crop rotation, as well as to the three different management systems, but in different ways. Under crop production, four years of organic management resulted in the highest soil organic C (SOC) and microbial biomass concentrations, while under forage production, reduced-tillage management most effectively increased SOC and microbial biomass. There were significant increases in relative abundance of bacteria, fungi, and protozoa, with two- to 36-fold increases in biomarker phospholipid fatty acids (PLFAs). Under crop production, dissolved organic C (DOC) content was higher under organic management than under reduced-tillage and conventional management. Perennial legume crops and organic soil amendments in the organic crop rotation system apparently favored greater soil microbial substrate availability, as well as more microbial biomass compared with other management systems that had fewer legume crops in rotation and synthetic fertilizer applications. Among the forage production management systems with equivalent crop rotations, reduced-tillage management had higher microbial substrate availability and greater microbial biomass than other management systems. Combined crop rotation, tillage management, soil amendments, and legume crops in rotations considerably influenced soil microbiotic properties. More research will expand our understanding of combined effects of these alternatives on feedbacks between soil microbiotic properties and SOC accrual.


Subject(s)
Agricultural Irrigation , Agriculture/methods , Bacteria/metabolism , Crops, Agricultural/growth & development , Food, Organic , Fungi/physiology , Soil Microbiology , Bacteria/drug effects , Biomass , Carbon/pharmacology , Crops, Agricultural/drug effects , Fungi/drug effects , Nitrogen/pharmacology , Principal Component Analysis , Wyoming
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