125 research outputs found
Uptake and movement of phosphorus (32P) in grapes
Phosphorus applied into the soil, appeared in the vine shoots within 24 hours of application, and the 6th bud of the shoot, which is generally the most fruitful region of shoots in the Anab-e-Shahi variety of grape, accumulated a high concentration of fertilizer P
Biochar Synthesis from Mineral- and Ash-Rich Waste Biomass, Part 1: Investigation of Thermal Decomposition Mechanism during Slow Pyrolysis
Synthesizing biochar from mineral- and ash-rich waste biomass (MWB), a by-product of human activities in urban areas, can result in renewable and versatile multi-functional materials, which can also cater to the need of solid waste management. Hybridizing biochar with minerals, silicates, and metals is widely investigated to improve parent functionalities. MWB intrinsically possesses such foreign materials. The pyrolysis of such MWB is kinetically complex and requires detailed investigation. Using TGA-FTIR, this study investigates and compares the kinetics and decomposition mechanism during pyrolysis of three types of MWB: (i) mineral-rich banana peduncle (BP), (ii) ash-rich sewage sludge (SS), and (iii) mineral and ash-rich anaerobic digestate (AD). The results show that the pyrolysis of BP, SS, and AD is exothermic, catalyzed by its mineral content, with heat of pyrolysis 5480, 4066, and 1286 kJ/kg, respectively. The pyrolysis favors char formation kinetics mainly releasing CO2 and H2O. The secondary tar reactions initiate from ≈318 °C (BP), 481 °C (SS), and 376 °C (AD). Moreover, negative apparent activation energies are intrinsic to their kinetics after 313 °C (BP), 448 °C (SS), and 339 °C (AD). The results can support in tailoring and controlling sustainable biochar synthesis from slow pyrolysis of MWB
Vehicle class wise speed-volume models for heterogeneous traffic
Link performance functions commonly used for traffic assignment are often based on Volume Delay Functions (VDF) developed for homogeneous traffic. However, VDFs relating stream speed to the volume of traffic based on homogeneous lane-based traffic are not adequate for traffic assignment in developing countries due to the heterogeneous nature of traffic that is characterized by a mix of a wide range of vehicle classes with significant differences in static and dynamic characteristics and an imperfect lane discipline. Unfortunately, the use of VDFs similar to those for homogeneous traffic flow situations imposes strong restrictions considering two respects: 1) travel times at path and link levels can be obtained for an aggregated stream but not for individual vehicle types; 2) the effect of varying composition and asymmetric interactions is captured only to a limited extent by converting all vehicles into equivalent Passenger Car Unit (PCU). Hence, this paper proposes the development of VDFs specific to different classes of heterogeneous traffic, as it is more realistic in traffic assignment than the use of the same VDF for all classes of vehicles in a link. This study is aimed at developing models to determine the speed of each vehicle class as a function of flow and composition for six lane roads with heterogeneous traffic based on data obtained from Chennai city, India. Heterogeneity in this study mainly refers to differences in vehicle types (two-wheeler, car, bus, etc.) participating in mixed traffic. To develop multiple user class VDFs, the speed and flow of each vehicle class for a wide range of traffic flow conditions need to be recorded. As this is not possible using field measurements, an established micro-simulation model (HETEROSIM) is used for determining speeds for each vehicle type by systematically varying the volume and composition levels over a range of values that represent relevant and practical traffic conditions observed in six lane divided roads in Chennai city. The proposed delay functions are different from standard single user class VDFs in three key respects: first, they enable more realistic behaviour by modelling differences in class wise speeds at a given volume and composition level; second, they allow for capturing asymmetric interactions of different vehicle types on an average speed of a given vehicle class. Finally, speed-flow relationships for each class are also allowed to vary across volume levels which enable the representation of differential interactions at different levels of congestion in mixed traffic. The need for homogenizing the volumes in terms of a single class is obviated. The models significantly outperformed single class VDFs in both calibration and validation datasets. Further, the proposed models are used for analyzing heterogeneous traffic characteristics. Empirical evidence of asymmetric interactions and the impact of composition on classwise performance are also found and quantified. Finally, two applications of the proposed models are demonstrated for the level of service analysis of different classes and impact analysis of excluding some classes. The proposed models may have applications such as determining class wise road user costs and performance measures (e.g. emissions) that depend on class-specific speeds
Biochar synthesis from mineral and ash-rich waste biomass, part 2: characterization of biochar and co-pyrolysis mechanism for carbon sequestration
The increase in mineral and ash-rich waste biomass (MWB) generation in emerging economies poses critical environmental problems and bottlenecks the solid waste and wastewater treatment systems. Transforming these MWB such as sewage sludge from wastewater treatment (SSW) to biochar can be a sustainable method for their disposal and resource recovery. However, such biochar has limited applicability due to the relatively low organic content and possibly contaminated nature of SSW. This may be offset through combined pyrolysis with other MWB, which can also support municipal solid waste management. Studies on this MWB co-pyrolysis are lacking and have not yet seen successful long-term implementation. This work is the second part of authors’ research encompassing an analytical and lab-scale investigation of biochar production from MWB through pyrolysis for the case of Chennai city, India. Here, the physicochemical properties of biochar derived from lab-scale co-pyrolysis of SSW with other MWB such as anaerobic digestate from waste to energy plants of food, kitchen or market waste fermentation, and banana peduncles (BP) collected from vegetable markets and their thermolysis mechanism are comprehensively investigated for purpose of carbon sequestration. Also, a novel preliminary investigation of the effect of sample weight (scaling effect) on the analytical pyrolysis of biomass (BP as model substrate) is undertaken to elucidate its impact on the heat of pyrolysis and carbon distribution in resultant biochar. The maximum carbon sequestration potential of the derived biochar types is 0.22 kg CO2 kg−1 biomass. The co-pyrolysis of MWB is exothermic and governed by the synergetic effects of the components in blends with emission profiles following the order CO2 > CH4 > CO > NH3. Co-pyrolysis reduced the heavy metal enrichment in SSW biochar. The derived biochars can be an immediate source of N, P and S in nutrient-deficient acidic soils. The biochar has only up to 4-ring polyaromatic compounds and a residence time longer than 1 h at 500 °C is necessary to improve carbonization. The heat released during analytical pyrolysis of the model biomass and distribution of carbon in the resultant biochar are significantly influenced by scaling effects, drawing attention to the need for a more detailed scaling investigation of biomass pyrolysis
The role of breast cancer oestrogen/progesterone receptor status in bone mineral density
This abstract was presented at the Osteoporosis Conference 2016, 7th - 9th November 2016, Birmingham, UK. This is the accepted manuscript version of the abstract. The final version is available online from Springer at: https://doi.org/10.1007/s00198-016-3743-zPublished versio
The impact of the COVID-19 pandemic and stringent social distancing measures on health-related quality of life and COVID-19 infection rates in patients with rheumatic disease: a longitudinal analysis through the pandemic
Objective The aim was to evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic and stringent social isolation measures on patients with rheumatic disease (RD) from the beginning of the pandemic (April 2020). Methods In this UK-based single-centre, prospective, observational cohort study, all RD follow-up patients at our centre were invited by SMS text message in April 2020 to participate in the study. Participants completed questionnaires at four time points between April 2020 and December 2021. We collected demographics, clinically extremely vulnerable (CEV) status, short form 12 mental (MCS) and physical health component scores (PCS) for health-related quality of life, vaccination status, COVID-19 infection rates and incidence of long COVID. Results We enrolled 1605 patients (female, 69.0%; CEV, 46.5%); 906 of 1605 (56.4%) completed linked responses to our final questionnaire. MCS improved (+0.6, P?<?0.05), whereas PCS scores deteriorated (-1.4, P?<?0.001) between April 2020 and December 2021. CEV patients had worse mental and physical health scores than non-CEV patients at entry (PCS, 36.7 and 39.3, respectively, P?<?0.001; MCS, 40.9 and 43.0, respectively, P?<?0.001) and at each time point throughout the study; both mental and physical health outcomes were worse in CEV compared with non-CEV patients (P?<?0.001 and P?=?0.004, respectively). At study close, 148 of 906 (16.3%) reported COVID infection, with no difference in infection, vaccination or long COVID rates between CEV and non-CEV patients. Conclusions Mental and physical health in RD patients has changed throughout the pandemic; outcomes for both metrics of health were worse in CEV patients, although there were no differences in infection rates between the groups. These data might assist the understanding and planning of future health-care policy and social restrictions in RD patients. Trial registration ClinicalTrials.gov, www.clinicaltrials.gov, NCT04542031
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Economic behavior of fishers under climate-related uncertainty: results from field experiments in Mexico and Colombia
This paper presents the results of economic experiments run among fishermen from the Mexican and Colombian Pacific. The experimental design aims at studying behavior under uncertainty concerning the possible effects of climate change on fisheries. We find that subjects’ risk-aversion diminishes the level of catches and changes fishing practices (e.g. adopting marine reserves), provided that fishermen have ex ante information on possible climatic consequences. Furthermore, social preferences (e.g. for cooperation and reciprocity) also play an important role regarding extraction from common-pool resources. Other factors, such as income, gender and religion are also found to have some influence. These results have important implications for adaptation actions and the management of coastal fisheries
Assignment of PolyProline II Conformation and Analysis of Sequence – Structure Relationship
International audienceBACKGROUND: Secondary structures are elements of great importance in structural biology, biochemistry and bioinformatics. They are broadly composed of two repetitive structures namely α-helices and β-sheets, apart from turns, and the rest is associated to coil. These repetitive secondary structures have specific and conserved biophysical and geometric properties. PolyProline II (PPII) helix is yet another interesting repetitive structure which is less frequent and not usually associated with stabilizing interactions. Recent studies have shown that PPII frequency is higher than expected, and they could have an important role in protein - protein interactions. METHODOLOGY/PRINCIPAL FINDINGS: A major factor that limits the study of PPII is that its assignment cannot be carried out with the most commonly used secondary structure assignment methods (SSAMs). The purpose of this work is to propose a PPII assignment methodology that can be defined in the frame of DSSP secondary structure assignment. Considering the ambiguity in PPII assignments by different methods, a consensus assignment strategy was utilized. To define the most consensual rule of PPII assignment, three SSAMs that can assign PPII, were compared and analyzed. The assignment rule was defined to have a maximum coverage of all assignments made by these SSAMs. Not many constraints were added to the assignment and only PPII helices of at least 2 residues length are defined. CONCLUSIONS/SIGNIFICANCE: The simple rules designed in this study for characterizing PPII conformation, lead to the assignment of 5% of all amino as PPII. Sequence - structure relationships associated with PPII, defined by the different SSAMs, underline few striking differences. A specific study of amino acid preferences in their N and C-cap regions was carried out as their solvent accessibility and contact patterns. Thus the assignment of PPII can be coupled with DSSP and thus opens a simple way for further analysis in this field
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