scholarly journals The contribution of organic acid on heterotrophic CO2 flux from tropical peat: a trenching study

2021 ◽  
Vol 9 (1) ◽  
pp. 3035-3044
Author(s):  
Siti Nurzakiah ◽  
Atang Sutandi ◽  
Gunawan Djajakirana ◽  
Untung Sudadi ◽  
Supiandi Sabiham
Keyword(s):  
Regression Analysis ◽  
Organic Acids ◽  
Groundwater Level ◽  
Seasonal Fluctuation ◽  
Co2 Flux ◽  
Available P ◽  
Co2 Production ◽  
Complex Nature ◽  
Main Determinant ◽  
One Year

Quantification of CO2 flux from peat has been studied with various methods of measurement and data analysis. Several studies have applied regression analysis to assess carbon flux from tropical peatland as a function of groundwater level. Such an analysis simplified the complex nature of peat decomposition, which involved microbial activities. The study was conducted at Buatan Village, Siak Indrapura Regency, Riau Province, Indonesia. Soil sampling was done every month for a year observation, from July 2018 to June 2019. This study aimed to comprehend CO2 production from the respiration of heterotrophic components (Rh-CO2) as a function of soil properties determined by soil pH, N-NH4, N-NO3, available P, exchangeable-K, C-organic acids, and environmental factors that are determined by soil water content, and groundwater level. The study applied trenching experimentation to quantify Rh-CO2 flux by first removing plant roots from the trenching plot. The CO2 flux and groundwater level were measured for five consecutive days each month for a one-year period. Multiple regression analysis was performed to determine the main determinant for the Rh-CO2 flux. The results showed that seasonal fluctuation of Rh-CO2 flux, negatively correlated with available P (p = 0.037), and positively (p = 0.018) with C-substrate as C-organic acids but not with either of the speciated ones as acetic, lactic, citric, malic, nor oxalic acids. More specifically, the C-organic acids were found as the main determinant factor (p = 0.039) affecting the Rh-CO2 flux.

scholarly journals Variation in Soil Properties Regulate Greenhouse Gas Fluxes and Global Warming Potential in Three Land Use Types on Tropical Peat

Atmosphere ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 465 ◽  
Author(s):  
Kiwamu Ishikura ◽  
Untung Darung ◽  
Takashi Inoue ◽  
Ryusuke Hatano
Keyword(s):  
Global Warming ◽  
Soil Moisture ◽  
Groundwater Level ◽  
Global Warming Potential ◽  
C:N Ratio ◽  
Co2 Flux ◽  
Nitrate Content ◽  
N2o Flux ◽  
Ch4 Flux ◽  
In The Beginning

This study investigated spatial factors controlling CO2, CH4, and N2O fluxes and compared global warming potential (GWP) among undrained forest (UDF), drained forest (DF), and drained burned land (DBL) on tropical peatland in Central Kalimantan, Indonesia. Sampling was performed once within two weeks in the beginning of dry season. CO2 flux was significantly promoted by lowering soil moisture and pH. The result suggests that oxidative peat decomposition was enhanced in drier position, and the decomposition acidify the peat soils. CH4 flux was significantly promoted by a rise in groundwater level, suggesting that methanogenesis was enhanced under anaerobic condition. N2O flux was promoted by increasing soil nitrate content in DF, suggesting that denitrification was promoted by substrate availability. On the other hand, N2O flux was promoted by lower soil C:N ratio and higher soil pH in DBL and UDF. CO2 flux was the highest in DF (241 mg C m−2 h−1) and was the lowest in DBL (94 mg C m−2 h−1), whereas CH4 flux was the highest in DBL (0.91 mg C m−2 h−1) and was the lowest in DF (0.01 mg C m−2 h−1), respectively. N2O flux was not significantly different among land uses. CO2 flux relatively contributed to 91–100% of GWP. In conclusion, it is necessary to decrease CO2 flux to mitigate GWP through a rise in groundwater level and soil moisture in the region.

scholarly journals The association between anxiety measured with HADS and use of psychotropic medication among cardiac patients

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
P.F Cromhout ◽  
A.V.C Christensen ◽  
M.B.J Joergensen ◽  
O.E Ekholm ◽  
K.J Juel ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Psychotropic Medication ◽  
Multiple Logistic Regression Analysis ◽  
Study Participant ◽  
Cardiac Patients ◽  
Funding Source ◽  
Cox Regression Analysis ◽  
Increased Risk ◽  
Patient Reported ◽  
One Year

Abstract Background Anxiety among cardiac patients is highly prevalent and is associated to poor outcomes. Certain types of psychotropic medication are suspected of causing adverse events in cardiac patients. However, an association between symptoms of anxiety and use of psychotropic medication among cardiac patients has not yet been established. Purpose The objective was to explore the association between anxiety (measured by HADS-A) and use of psychotropic medication among cardiac patients. Methods All study participant were identified from the DenHeart study and data were a combination of patient-reported survey data and baseline and follow-up data from Danish national registers. Information on redeemed prescriptions of psychotropic medication was obtained from The Danish National Prescription Registry. Anxiety symptoms were defined by a HADS-A score≥8. Patients were defined as users of psychotropic medication if they had redeemed at least one prescription one and three years after discharge. Psychotropic medication was classified by Anatomical Therapeutic Chemical Classification (ATC) codes. Multiple logistic regression analysis within one year and Cox regression analysis within three year from discharge was conducted to determine the association between symptoms of anxiety and use of psychotropic medication. Results Among the 12,913 cardiac patients included, a total of 3231 (28%) redeemed at least one prescription of psychotropic medication within one year and 4726 (37%) within three years after discharge. The most commonly used drugs were benzodiazepines and antidepressants. Among patients using psychotropic medication 1481 (46%) had a HADS-A score ≥8. Cardiac patients with symptoms of anxiety had significantly higher odds of using psychotropic medication within one year from discharge OR 2.47 (95% CI 2.25; 2.72). The increased risk of use of psychotropic medication was confirmed with a almost two-fold risk after three years, HR 1.92 (95% CI 1.80; 2.04), Table 1. Conclusion Cardiac patients with symptoms of anxiety measured by HADS were significantly more likely to use psychotropic medication within one and three years after discharge than cardiac patients without symptoms of anxiety. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Novo Nordisk Foundation

Fire regime impacts on post-fire diurnal land surface temperature change over North American boreal forest

2021 ◽  
Author(s):  
Jie Zhao ◽  
Chao Yue ◽  
Philippe Ciais ◽  
Xin Hou ◽  
Qi Tian
Keyword(s):  
Climate Change ◽  
Regression Analysis ◽  
Land Surface ◽  
Fire Regime ◽  
Fire Severity ◽  
Linear Regression Analysis ◽  
Fire Regimes ◽  
Fire Intensity ◽  
Surface Temperature Change ◽  
One Year

<p>Wildfire is the most prevalent natural disturbance in the North American boreal (BNA) forest and can cause post-fire land surface temperature change (ΔLST<sub>fire</sub>) through biophysical processes. Fire regimes, such as fire severity, fire intensity and percentage of burned area (PBA), might affect ΔLST<sub>fire</sub> through their impacts on post-fire vegetation damage. However, the difference of the influence of different fire regimes on the ΔLST<sub>fire</sub> has not been quantified in previous studies, despite ongoing and projected changes in fire regimes in BNA in association with climate change. Here we employed satellite observations and a space-and-time approach to investigate diurnal ΔLST<sub>fire</sub> one year after fire across BNA. We further examined potential impacts of three fire regimes (i.e., fire intensity, fire severity and PBA) and latitude on ΔLST<sub>fire</sub> by simple linear regression analysis and multiple linear regression analysis in a stepwise manner. Our results demonstrated pronounced asymmetry in diurnal ΔLST<sub>fire</sub>, characterized by daytime warming in contrast to nighttime cooling over most BNA. Such diurnal ΔLST<sub>fire</sub> also exhibits a clear latitudinal pattern, with stronger daytime warming and nighttime cooling one year after fire in lower latitudes, whereas in high latitudes fire effects are almost neutral. Among the fire regimes, fire severity accounted for the most (43.65%) of the variation of daytime ΔLST<sub>fire</sub>, followed by PBA (11.6%) and fire intensity (8.5%). The latitude is an important factor affecting the influence of fire regimes on daytime ΔLST<sub>fire</sub>. The sensitivity of fire intensity and PBA impact on daytime ΔLST<sub>fire</sub> decreases with latitude. But only fire severity had a significant effect on nighttime ΔLST<sub>fire</sub> among three fire regimes. Our results highlight important fire regime impacts on daytime ΔLST<sub>fire</sub>, which might play a critical role in catalyzing future boreal climate change through positive feedbacks between fire regime and post-fire surface warming.</p>

scholarly journals FAKTOR –FAKTOR YANG MEMPENGARUHI KEPATUHAN PAJAK WAJIB PAJAK ORANG PRIBADI (Studi Pada Wajib Pajak Orang Pribadi yang terdaftar di KPP Kebayoran Baru Tiga)

2014 ◽  
Vol 1 (1) ◽  
pp. 51
Author(s):  
Fibria Anggraini P.L ◽  
Waluyo Waluyo
Keyword(s):  
Regression Analysis ◽  
Organizational Climate ◽  
Survey Design ◽  
Linear Regression Analysis ◽  
Tax Compliance ◽  
Multiple Linear Regression Analysis ◽  
Individual Behavior ◽  
Behavior Motivation ◽  
Independent Variable ◽  
One Year

The purpose of this study was to analyze the factors that affect tax compliance (tax compliance) individual taxpayers in the KPP Kebayoran Baru Tiga, South Jakarta. This study used a questionnaire survey design as an instrument. Respondents in this study were 85 individual taxpayers entrepreneur tax register at least one year and to submit the SPT.This study uses the variable individual behavior, motivation and organizational climate as the independent variable and tax compliance individual taxpayers as the dependent variable. Data analysis was performed using multiple linear regression analysis with SPSS for Windows Version 19.00. The results of this study indicate that individual behavior, motivation and organizational climate have significant effect on tax compliance individual taxpayers .

Derivation of CO2 output from oscillations in arterial pH

1987 ◽  
Vol 62 (3) ◽  
pp. 880-891 ◽  
Author(s):  
B. A. Cross ◽  
R. P. Stidwill ◽  
K. D. Leaver ◽  
S. J. Semple
Keyword(s):  
Maximum Rate ◽  
Venous Blood ◽  
Co2 Flux ◽  
Limited Range ◽  
Co2 Production ◽  
Mixed Venous Blood ◽  
Co2 Partial Pressure ◽  
Co2 Output ◽  
Arterial Ph ◽  
Small Rise

Theory predicts that the rate of rise of the oscillation in arterial CO2 partial pressure (PaCO2) is linearly dependent on CO2 flux from venous blood to alveolar gas. We have measured, in the anesthetized cat, CO2 output (VCO2) and oscillations in arterial pH. The pH signal was differentiated to give the maximum rate of fall of pH on the downstroke of the oscillation (dpH/dt decreases max). Since oscillations in pH are due to oscillations in arterial PCO2, dpH/dt decreases max was considered to be equivalent to the maximum rate of rise of the PCO2 oscillation. VCO2 was increased by ventilating the intestines with CO2 and by the intra-arterial infusion of 2,4-dinitrophenol. VCO2 was decreased by filling the intestines with isotonic tris(hydroxymethyl)methylamine buffer. The maximum range of VCO2 covered was 7.8–51 ml/min, and the mean range was from 13.6 +/- 1.3 to 29.7 +/- 1.6 (SE) ml/min. Although CO2 loading produced a small rise and CO2 unloading a small fall in mean PaCO2, the changes were not statistically significant, so that overall the response was close to isocapnia. Over the limited range of VCO2 studied there was a highly significant linear association between dpH/dt decreases max and VCO2 which supports the contention that the slope of the upstroke of the PaCO2 oscillation is determined by the CO2 flux from mixed venous blood to alveolar gas. As such this slope is a potential chemical signal linking ventilation to CO2 production.

Effects of glycogen depletion and work load on postexercise O2 consumption and blood lactate

1979 ◽  
Vol 47 (3) ◽  
pp. 514-521 ◽  
Author(s):  
S. S. Segal ◽  
G. A. Brooks
Keyword(s):  
Blood Lactate ◽  
Slow Component ◽  
Minute Ventilation ◽  
Co2 Flux ◽  
Work Load ◽  
Bicycle Ergometer ◽  
Co2 Production ◽  
O2 Consumption ◽  
Glycogen Depletion ◽  
Heavy Exercise

To study a possible relationship between blood lactate and O2 consumption (VO2) after exercise, 11 male subjects exercised on a bicycle ergometer at moderate and heavy work loads in both normal glycogen and glycogen-depleted states. At rest, glycogen depletion resulted in significantly lowered blood glucose and lactate concentrations, CO2 production (VCO2), respiratory exchange ratio (R), and minute ventilation (VE). With the exception of glucose, these variables changed more in response to heavy exercise (HE: 2 min at a mean of 1,750 kg.m/min) than to moderate exercise (ME: 2 min at a mean of 1,000 kg.m/min). At either work load, VCO2, R, and lactate showed consistently greater responses in the normal glycogen state. The slope of the initial component of the postexercise VO2 curve was unaffected by either work load or lactate. Although the slope of the slow component of the postexercise VO2 curve became significantly more negative after HE, it was unaffected by the level of lactate. These results are inconsistent with the hypothesis of a “lactacid O2 debt.” Exercise intensity was the predominant factor influencing the magnitude and kinetics of postexercise VO2. Glycogen depletion resulted in lower VCO2, R, and blood lactate, but higher VE during heavy exercise. The results suggest that factors, in addition to CO2 flux to the lungs, influence VE during exercise.

scholarly journals Assessing the suitability of extreme learning machines (ELM) for groundwater level prediction

2017 ◽  
Vol 32 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Basant Yadav ◽  
Sudheer Ch ◽  
Shashi Mathur ◽  
Jan Adamowski
Keyword(s):  
Soft Computing ◽  
Groundwater Level ◽  
Groundwater Resources ◽  
Support Vector ◽  
Complex Nature ◽  
Data Set ◽  
Groundwater Levels ◽  
Soft Computing Techniques ◽  
Learning Machine ◽  
The Comparative Study

Abstract Fluctuation of groundwater levels around the world is an important theme in hydrological research. Rising water demand, faulty irrigation practices, mismanagement of soil and uncontrolled exploitation of aquifers are some of the reasons why groundwater levels are fluctuating. In order to effectively manage groundwater resources, it is important to have accurate readings and forecasts of groundwater levels. Due to the uncertain and complex nature of groundwater systems, the development of soft computing techniques (data-driven models) in the field of hydrology has significant potential. This study employs two soft computing techniques, namely, extreme learning machine (ELM) and support vector machine (SVM) to forecast groundwater levels at two observation wells located in Canada. A monthly data set of eight years from 2006 to 2014 consisting of both hydrological and meteorological parameters (rainfall, temperature, evapotranspiration and groundwater level) was used for the comparative study of the models. These variables were used in various combinations for univariate and multivariate analysis of the models. The study demonstrates that the proposed ELM model has better forecasting ability compared to the SVM model for monthly groundwater level forecasting.

Phenomenon of Pain In Thalassemia: A Prospective Analysis by the Thalassemia Clinical Research Network (TCRN)

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 256-256
Author(s):  
Dru Haines ◽  
Susan Carson ◽  
Sage Green ◽  
Marie Martin ◽  
Thomas D. Coates ◽  
...  
Keyword(s):  
Chronic Pain ◽  
Regression Analysis ◽  
Pain Relief ◽  
Research Funding ◽  
Ordinal Regression ◽  
Research Network ◽  
Beta Thalassemia ◽  
Lower Back ◽  
Ordinal Regression Analysis ◽  
One Year

Abstract Abstract 256 Background: Pain is not a symptom generally associated with thalassemia. However, healthcare providers have anecdotally noted increasing patient reports of chronic pain over the last decade creating an impetus for the TCRN to conduct this prospective, observational assessment of pain in patients with thalassemia over the age of 12. Study goals include assessment of pain prevalence, severity and sites and whether these factors are impacted by age, gender or diagnosis. Methods: Pain was assessed quarterly using the Brief Pain Inventory (BPI). Two hundred fifty-one thalassemia patients ranging in age from 12 to 71 (average age of 28.75) receiving care at one of 12 thalassemia centers across the US and Canada participated in the study. Fifty-four percent of participants were female. Diagnoses included: Beta Thalassemia (80%), E Beta thalassemia (11%), Hemoglobin H and H Constant Spring (6%) and other thalassemia conditions (3%). Eighty percent of participants were chronically transfused, 6% intermittently transfused and 14% had never been transfused. This report reviews baseline findings. Results: At study entry, 64% of the 251 participants reported experiencing pain over the last four weeks, of whom 21% reported pain on a daily basis. In comparison, 26% of the American public, 20 years and older, reported pain over a one month period according to National Center for Health Statistics data, 2006. Ordinal regression analysis of participant ratings of worst, least, and average pain over the last seven days demonstrated significant (p<0.001) correlation of increased age with increased pain across all categories irrespective of diagnosis, transfusion status or gender. Similarly, ordinal regression analysis revealed that pain increased with participant age and significantly correlated (p<0.001) with a negative impact of pain on patient's affect and activity as measured by the BPI interference scales. Eighty-two percent of those reporting pain indicated lower back as a site of pain. In logistic regression models, lower back (p=0.046), arm (p=0.047) and hip (p=0.009) pain significantly increased with age. The number of bodily pain sites (p=0.033) also increased with age which was determined using linear regression. Among patients reporting pain in the last seven days, 77% reported having pain for one year or longer and 26% reported pain for 5 or more years. Participants reporting pain in the last 7 days identified the following reasons for their pain: thalassemia (60%), low hemoglobin (55%), bone pain (37%) and muscle spasm (30%). Participants indicated multiple methods of managing pain including: blood transfusion (54%), rest (51%) massage (46%) and heat (39%). Medications were the most frequently cited pain intervention (72 % of participants) with the most common mediations taken being NSAIDs (71%), followed by acetaminophen (48%), short acting narcotics (24%) and long acting narcotics (11%). Twenty-five percent of participants reported they received no pain relief from medications or non-pharmaceutical treatments, and only 4% reported they received complete pain relief with treatment. Half the population reported they gained about 50% relief from pain with treatments. Conclusions: These data show that pain is a significant issue for patients with thalassemia and as patient's age pain increases. Pain assessment should be conducted on a regular basis for all patients with thalassemia since neither transfusion status nor diagnosis are a reliable indicator of pain status. The study also indicates that chronic pain (pain lasting greater than one year) is an issue for thalassemia patients and underscores the need for further study of pain in this population. Analysis of pain follow up data collected at 3 month intervals post baseline is being conducted to assess whether severity levels vary over time. Disclosures: Coates: Novartis: Research Funding, Speakers Bureau. Neufeld:Novartis, Inc: Research Funding; Ferrokin, Inc: Research Funding.

scholarly journals The epidemiology of beta-haemolytic non-Group A streptococci isolated from the throats of children over a one-year period

1990 ◽  
Vol 104 (1) ◽  
pp. 119-126 ◽  
Author(s):  
N. Cimolai ◽  
L. MacCulloch ◽  
S. Damm
Keyword(s):  
Seasonal Fluctuation ◽  
Paediatric Population ◽  
Streptococcal Pharyngitis ◽  
Clinical Impression ◽  
Group A Streptococci ◽  
Case Control Studies ◽  
Large Colony ◽  
Streptococcus Milleri ◽  
Group A ◽  
One Year

SUMMARYThe incidence of beta-haemolytic non-Group A streptococci (BHNAS) in the throats of a paediatric population was examined over a 1-year period. There was minimal seasonal fluctuation of Lancefield groups including species and biotypes within Groups C and G streptococci. A trend of increasing incidence with age ofStreptococcus anginosus(‘Streptococcus milleri’) (possessing Groups C and G Lancefield antigens) was evident. A clinical impression of streptococcal pharyngitis was more common in patients with large-colony Groups C or G streptococci isolated from their throats compared with those patients where other BHNAS were isolated. This study is requisite to the planning of case control studies which are required to test the association of BHNAS (especially Groups C and G subgroups) and pharyngitis.

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