67 research outputs found
An assessment of Information disclosures by Pharmaceutical Industry: Evidence from India
[EN] The information disclosed by the companies in their annual reports reveals much about company’s performance and prospects. Investors take the information as base for decision for investment. Under such circumstance, companies choose to disclose beyond what is mandatorily required. Theories like agency theory, capital need theory and signaling theory support the need of voluntary disclosure. This study is about investigating the extent of Voluntary disclosure in pharmaceutical sector of India which is 3rd in World in terms of Volume of Trade.Objective: To investigate the extent of voluntary disclosure practices prevailing in pharma sector of India, for the year 2010-11 to 2017-18.Significance of the study: This study aims to explore the corporate aspect of pharmaceutical sector. Any growing avenue is a potential opportunity for investors looking for parking their money to get adequate returns. Thus, Indian Pharma sector has come up in flying colors as an avenue for investors to place their money owing to its 100% FDI . Investors have been looking for more and more information from this sector to ensure the safety of funds. Thus the extent of disclosures is worth studying to place a suggestion for the policymakers to introduce the changes in the present set of disclosure practices in pharmaceutical sector.Research Methodology: To understand the extent of voluntary disclosure, a disclosure checklist is constructed and descriptive statistics are carved out to reach the results. The checklist consists of 55 items which are not mandatory by law. The checklist is based on dichotomous scale of ‘1’ and ‘0’ representing presence and absence of the checklist item respectively. The cross sectional analysis is carried out to investigate the year wise and company wise disclosure for eight years.Findings: Though the study observes an increasing trends in the disclosure scores, but the findings are alarming to state that the highest score attained by any company throughout the period of 8 years was 37 (out of 55) not even meeting 80% of the total checklist score. This shows that pharmaceutical sector is not so friendly at disclosures. The probable reasons for such startling results are discussed in the study.Khanna, R.; Chahal, BPS. (2019). An assessment of Information disclosures by Pharmaceutical Industry: Evidence from India. Multidisciplinary Journal for Education, Social and Technological Sciences. 6(2):147-174. https://doi.org/10.4995/muse.2019.11531SWORD14717462Accounting, F. (2014). 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Household symptomatic contact screening of sputum smear positive tuberculosis patients at the DOTS clinic of SGT hospital, Gurugram
Background: Contact screening was conducted under ICMR (REFERENCE ID: 2019-07811) programme in villages near SGT hospital, Gurugram. Objective: To evaluate risk factors, extent of spread of tuberculosis among household contacts of tuberculosis cases and to create awareness. Methods and Material: Address of TB cases were taken from RNTCP register at DOTS clinic, SGT medical college. Then all household contacts of positive cases were screened, counselled and advised to approach ASHA Workers if such symptoms appear. Data was analysed using appropriate statistical methods. Results:21 Index cases along with 94 household contacts were screened. 61.90% families still use chullahs for cooking. 76.1% families have overcrowding. 3) 61.90% families had inadequate ventilation 4) 19.05%families were aware about the spread of this disease. 5)Only 23.80% families practised adequate sanitation methods and precautions6) 42.8% Index cases had a history of smoking. 7) 44.4% 4 continue to smoke with infection. The association of adequate sanitation with presence of awareness was found to be statistically significant. (p-value<0.05). Other factors were not significantly associated with level of awareness regarding prevention of tuberculosis spread among study participants. Conclusions: Contact screening is an effective tool and it gives the real-time picture of TB in India
Interactive effects of rice-residue biochar and N-fertilizer on soil functions and crop biomass in contrasting soils
There is limited understanding of the effects of rice residue biochar, particularly when applied in combination with nitrogen (N) fertilizer on soil fertility, soil C sequestration and crop productivity. A one-year pot experiment was established to examine effects of rice residue biochar (0, 10, 20 and 40 t ha-1) and N (0, 60, 90, 120 and 150 kg N ha-1) in soils with contrasting texture (loamy sand and sandy clay loam) in a wheat(maize cropping sequence. Biochar was only applied once before sowing wheat. Biochar alone or in combination with N did not significantly increase wheat biomass in both soils, whereas biomass of maize (next crop) was significantly increased from the residual effect of biochar, alone or in combination with N fertilizer. In both soils, electrical conductivity (EC) and pH, oxidisable organic carbon (OC), microbial biomass carbon (MBC), dissolved organic carbon (DOC) and available nutrients (NPK) increased with increasing rates of biochar addition. However, addition of N with biochar (cf. biochar alone) did not change pH and oxidisable OC values but increased EC significantly. After one year, the soil organic carbon (SOC) stocks increased beyond the input of biochar-C, that is, by 0.1-2.1 t ha-1 and 1.8-4.8 t ha-1 in loamy sand and sandy clay loam, respectively, across all treatments. It may be concluded that the potential benefits of rice residue biochar to soil functions and crop production may encourage growers to minimise open field burning of straw, which is a common practice in the region
Effect of crop residue addition on soil organic carbon priming as influenced by temperature and soil properties
Priming of soil organic carbon (SOC) is a crucial factor in ecosystem carbon balance. Despite its increasing importance in the changing global climate, the extent of influence of temperature and soil properties on the priming effect remains unclear. Here, soil priming was investigated using 13C labeled wheat residues in two cultivated, subtropical (Vertisol) and semi-arid (Luvisol), soils of Australia at four incubation temperatures (13, 23, 33 and 43 °C). The priming effect was computed from respired CO2 and associated δ13C, which were measured periodically over the 52-day incubation period. Wheat residue addition resulted in greater priming effect in the Luvisol (1.17 to 2.37% of SOC) than the Vertisol (0.02 to 1.56% of SOC). The priming of SOC was the highest at 23 °C in the Luvisol, and at 43 °C in the Vertsiol, which indicates a variable positive priming effect of temperature in different soil types. Wheat residue addition significantly increased the temperature sensitivity (Q10) of SOC mineralization in the Vertisol at temperature ranges below 33 °C (i.e., 13–23 and 23–33 °C) and had no significant effect in the Luvisol. A negative correlation was observed between temperature and the Q10 values. Across soils, the Q10 of residue C was lower than SOC suggesting that soil C is more vulnerable to climatic warming. This work demonstrates that the magnitude of SOC priming by wheat residue and Q10 of SOC mineralization varied significantly with soil type (Luvsiol > Vertisol) and incubation conditions (temperature and time). Given the current trend towards increasing atmospheric temperatures, future studies should evaluate temperature effects on the priming of different pools of SOC induced by crop residue in different agro-ecosystems
Management of Pasture Soils: Biochar Stability, Carbon Storage Potential and Its Effect on Production and Quality
The use of biochar has been proposed as a stable carbon (C) amendment with long-term carbon (C) storage potential in agricultural soils while improving primary productivity. However, this concept has not been widely tested in contrasting soils under temperate pasture systems. To address this knowledge gap, a 13C-labelled biochar, produced from Eucalyptus saligna biomass by slow pyrolysis (450° C; d13C -36.7‰) was surface (0 10 cm) applied in C3 dominated, annual temperate pasture systems across Arenosol, Cambisol and Ferralsol. The results show that only 2% of the applied biochar-C was mineralised in a relatively clay- and C-poor Arenosol, 4.6% in a clay- and C-rich Cambisol, and 7% in a clay- and C-rich and earthworm-abundant Ferralsol over 12 months. Biochar application increased soil C stock, while the mean residence time of biochar-C, an indicator of its stability in soil, decreased with increasing native C content and/or pasture productivity across the soils i.e. Arenosol (71 years) \u3c Cambisol (39 years) \u3c Ferralsol (29 years). Biochar application increased pasture growth rate only on two occasions over 12 months in the Ferralsol but not in the other pasture-soil systems. The biochar-C recovery to 12 30 cm depth varied as 1.2% (Arenosol), 2.7% (Cambisol) and 15.7% (Ferralsol) after 12 months. Cumulative CO2-C emission from native soil-plant sources was lower (p \u3c 0.10) in the biochar-amended vs. non-amended Ferralsol. This study shows that the downward migration of biochar-C exceeded its loss via mineralisation in the Arenosol and Ferralsol but in the Cambisol. This migration of biochar to deeper soil layers could enhance C sequestration potential in soil systems
Multiple trade-offs between maximizing yield and minimizing greenhouse gas production in Chinese rice croplands
Globally, paddy fields are a major anthropogenic source of greenhouse gas (GHG) emissions from agriculture. There is, however, limited understanding of relationships between GHG production with fertilizer management, rice varieties, and soil variables. This information is crucial for minimizing the climatic impacts of rice agriculture. Here, we examined the relationships between soil GHG production and management practices throughout China. The current doses of N-fertilizer (73-272 kg ha−1) were negatively correlated with rice yield and with CO2 or CH4 production and positively correlated with N2O production, thus suggesting N-overfertilization. Impacts on soil traits such as decreasing pH or the availabilities of other nutrients could be underlying these relationships. Rice yield was highest, and GHG production was lowest at sites using intermediate levels of P- and K-fertilization. CO2 and CH4 production and emissions were positively related with soil water content. The yield was higher, and N2O productions were lower at the sites with japonica rice. Our results strongly suggest that current high doses of N-fertilizers could be reduced to thus avoid the negative effects of excessive N input on GHG production without any immediate risk of rice production loss. Current intermediate doses of P- and K-fertilization should be adopted across China to further improve rice production without the risk of GHG emissions. The use of different rice varieties and strategies of water management should be reexamined in relation to crop production and GHG mitigation
Effects of soil grain size and solution chemistry on the transport of biochar nanoparticles
Biochar nanoparticles (BC-NP) have attracted significant attention because of their unique environmental behavior, some of which could potentially limit large-scale field application of biochar. Accurate prediction of the fate and transportability of BC-NP in soil matrix is the key to evaluating their environmental influence. This study investigated the effects of soil grain size and environmentally relevant solution chemistry, such as ionic strength (cation concentration, 0.1 mM–50 mM; cation type, Na+, and Ca2+), and humic acid (HA; 0–10 mg/L), on the transport behavior of BC-NP via systematic column experiments. The transportability of BC-NP in the soil-packed column decreased with decreasing soil grain size and was inversely proportional to soil clay content. At low cation concentrations (0.1–1.0 mM), a considerable proportion of BC-NP (15.95%–67.17%) penetrated the soil columns. Compared with Na+, Ca2+ inhibited the transportability of BC-NP in the soil through a charge shielding effect. With increasing HA concentration, the transportability of BC-NP increased, likely due to an enhanced repulsion force between BC-NP and soil particles. However, at a high HA concentration (10 mg/L), Ca2+ bridging reduced the transportability of BC-NP in the soil. Breakthrough curves of BC-NP were explained by the two-site kinetic retention model. The antagonistic effects of ionic strength and HA indicated that the transport behavior of BC-NP in the soil was governed by competitive effects of some environmental factors, including soil grain size, environmental solution chemistry, and natural organic matter content
Studies on the dynamics of organic sulphur and carbon in pastoral and cropping soils : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University
Soil organic matter (SOM) can be depleted or regenerated by altering land management practices. Soil tests capable of reporting the size of dynamic SOM fractions may be useful for indicating the environmental cost of landuse and management practices. Information on the effect of land management practices on soil organic S content and turnover is scarce. This study evaluated the ability of a sequential chemical fractionation procedure to characterise changes in soil S and C organic fractions on a range of pasture and cropping soils with different management histories. The fractionation involved an initial extraction with ion exchange resins followed by dilute (0.1 M NaOH) and concentrated (1 M NaOH) alkali. In addition, recently rhizodeposited 14C (root+exudate derived) produced during a short-term (one week) 14CO2 pulse-labelling study of intact soil cores growing ryegrass/clover pastures, was used to trace the fate of root-derived C in both chemical and density fractionation procedures. In pasture and cropped topsoils, the major amounts of soil S and C were either extracted in 0.1 M NaOH (49-69% S and 38-48% C) or remained in the alkali-insoluble residual fraction (17-38% S and 46-53% C). These two fractions were more sensitive to change caused by different landuse and management practices than the resin and 1 M NaOH fractions. With a large amount of dynamic soil C remaining in the residual fraction it was concluded that increasing strengths of alkali were not capable of sequentially fractionating S and C in SOM into decreasingly labile fractions. The chemical fractionation allocated recent root and root-released 14C amongst all the fractions. Again, most root 14C appeared in the 0.1 M NaOH and residual fractions. Although small in amount, C of higher specific activity (more recently synthesised root C) was preferentially extracted by resin and 1 M NaOH extracts. Density separation was not capable of recovering recent root and root-released 14C in a single fraction. Root-derived 14C was distributed between light (mostly fibrous root debris) (42%) and heavy (organics attached to clay and silt) (45%) fractions. The dispersing reagent soluble fraction recovered <13% of the 14C. An anaerobic incubation and various acids and oxidising agents were tried, in order to recover a greater proportion of root and root-released 14C as a single identity. These were not very successful in either extracting or increasing the alkali solubility of the root C fraction. A 30% H2O2 pretreatment of soil plus roots, or hot 1 M HNO3 treatment of the residual fraction, were more efficient extractants of the root C fraction and should be investigated further to check their ability to better characterise soil organic S and C fractions with a change in management practices. The 14CO2 pulse labelling study of pasture swards showed a greater allocation of recently photo-assimilated 14C to the topsoil layer with a greater proportion of 14C recovered in roots than in the soil. An in situ soil solution sampling technique with mini Rhizon Soil Moisture samplersTM effectively monitored the rapid appearance of a 14CO2 pulse in soil water at various depths. A comparison of the 14CO2 pulse labelling study under light and dark conditions indicated that, in the light lysimeters, 14CO2 photo-assimilation/translocation/rhizosphere respiration was the main pathway for CO2 generation at various soil depths. In the dark lysimeters, 14CO2 diffusion was the main mechanism and 14C assimilation (either photo-assimilation or assimilation by chemolithotrophs in rhizosphere soil) was small. The 14CO2 activity in soil water from four soil depths of dark and light soil cores, and a CO2 diffusion model, were used to identify the 14CO2 contribution from rhizosphere respiration in the light lysimeters. A model was developed, but the unknown geometry of the air-filled pore space in the undisturbed soil cores made it impossible to precisely calculate the contribution made by root respiration to soil water 14CO2 activity
Long-term influence of biochar on native organic carbon mineralisation in a low-carbon clayey soil
Biochar can influence native soil organic carbon (SOC) mineralisation through "priming effects". However, the long-term direction, persistence and extent of SOC priming by biochar remain uncertain. Using natural ¹³C abundance and under controlled laboratory conditions, we show that biochar-stimulated SOC mineralisation ("positive priming") caused a loss of 4 to 44 mg C g⁻¹ SOC over 2.3 years in a clayey, unplanted soil (0.42% OC). Positive priming was greater for manure-based or 400°C biochars, cf. plant-based or 550°C biochars, but was trivial relative to recalcitrant C in biochar. From 2.3 to 5.0 years, the amount of positively-primed soil CO₂-C in the biochar treatments decreased by 4 to 7 mg C g⁻¹ SOC. We conclude that biochar stimulates native SOC mineralisation in the low-C clayey soil but that this effect decreases with time, possibly due to depletion of labile SOC from initial positive priming, and/or stabilisation of SOC caused by biochar-induced organo-mineral interactions
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