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Distribution of methanogenic and methanotrophic consortia at soil-water interfaces in rice paddies across climate zones
Full text linkPeriphytic biofilms (PB) at the soil-water interface contributes 7–38% of the methane emission from rice paddies, yet the biogeographical mechanism underlying and affecting the process remain elusive. In this study, rice fields along an edapho-vclimatic gradient were sampled, and the environmental drivers affecting distribution of methanogenic and methanotrophic communities were evaluated. The methanogenic and methanotrophic communities at soil-water interface showed less complex inter/intra-generic interactions than those in soil, and their relative abundances were weakly driven by spatial distance, soil organic carbon, soil total nitrogen and pH. The nutrient supply and buffering capacity of extracellular polymeric substance released by PB reduced their interaction and enhanced the resilience on edaphic environment changes. Climate affected soil metal content, extracellular polymeric substance content, and thus the methane-related communities, and caused geographical variation in the impacts of PB on methane emissions from rice paddies. This study facilitates our understanding of geographical differences in the contribution of PB to methane emission
Manslaughter, Concealment of Birth and Infanticide, 1900-37
Full text linkThe Infanticide Act 1922 originated as one of a series of proposals to downgrade most cases of neonaticide from murder to manslaughter, but was redrafted by the Lord Chancellor’s Department to create a separate offence which was also a defence to murder. Thus, manslaughter verdicts could still be returned, as in a number of cases in the years leading up to the Act, where the prosecution could not prove the mens rea for murder, and infanticide would be available where the mens rea for murder was present but there were extenuating circumstances that could be described as the balance of the defendant’s mind being disturbed. Within a few years, however, infanticide was being treated as a very minor offence, with Swift J stating in one case that he considered it less serious than concealment of birth – the offence a mother was convicted of where it could not be proved that the baby was born alive and died as a result of the mother’s act or omission. This chapter explores the relationship between the four offences for which conviction was possible in cases of suspected neonaticide and considers in particular infanticide can, as Emma Milne has suggested, be regarded as introducing a form of ‘reproductive justice’ into the courtroom in the guise of a mental condition defence
Grey-based taguchi method for multi-weld quality optimization of gas metal arc dissimilar joining of mild steel and 316 stainless steel
Full text linkWelding processes play a significant role in many fabrication and manufacturing industries. Among various welding processes that have been developed over the years, Gas Metal Arc Welding (GMAW) or Metal Inert Gas Welding (MIG) has received a lot of interest due to its ability to weld a variety of metallic materials, easy adaptation for automation, high deposition rate, high efficiency, and low capital requirement. This study focus on the optimization of the multi-performance characteristics of MIG welded butt joint of AISI 1008 mild steel and AISI 316 austenitic stainless steel by hybrid Grey based Taguchi method. L9 Taguchi orthogonal array was adopted for the optimization of the MIG welding current, voltage and gas flow rate. The weld joint integrity has been assessed in terms of the tensile strength, yield strength, percentage elongation and Vickers microhardness of the fusion zone. Welding current of 180 A, voltage of 14 V, and gas flow rate of 19 l/min were obtained as the optimal parameter setting for the MIG welding process. The tensile strength, yield strength, percentage elongation and hardness of 559.25 MPa, 382.22 MPa, 33.34%, and 250.63 HV respectively were obtained at the optimal setting. Voltage was the most significant process parameter with 63.76% contribution for the multi-performance of the weldments. The confirmatory test was performed to validate the optimization process which proved Grey based Taguchi method to be an easy but yet effective method for multi-performance characteristics optimization of welded joints
Tracheostomy in children is associated with neutrophilic airway inflammation
Full text linkBackground Tracheostomies in children are associated with significant morbidity, poor quality of life, excess healthcare costs and excess mortality. The underlying mechanisms facilitating adverse respiratory outcomes in tracheostomised children are poorly understood. We aimed to characterise airway host defence in tracheostomised children using serial molecular analyses.
Methods Tracheal aspirates, tracheal cytology brushings and nasal swabs were prospectively collected from children with a tracheostomy and controls. Transcriptomic, proteomic and metabolomic methods were applied to characterise the impact of tracheostomy on host immune response and the airway microbiome.
Results Children followed up serially from the time of tracheostomy up to 3 months postprocedure (n=9) were studied. A further cohort of children with a long-term tracheostomy were also enrolled (n=24). Controls (n=13) comprised children without a tracheostomy undergoing bronchoscopy. Long-term tracheostomy was associated with airway neutrophilic inflammation, superoxide production and evidence of proteolysis when compared with controls. Reduced airway microbial diversity was established pre-tracheostomy and sustained thereafter.
Conclusions Long-term childhood tracheostomy is associated with a inflammatory tracheal phenotype characterised by neutrophilic inflammation and the ongoing presence of potential respiratory pathogens. These findings suggest neutrophil recruitment and activation as potential exploratory targets in seeking to prevent recurrent airway complications in this vulnerable group of patients
Thermodynamic restrictions determine ammonia tolerance of methanogenic pathways in Methanosarcina barkeri
Full text linkAmmonia is a ubiquitous potential inhibitor of anaerobic digestion processes, mainly exhibiting inhibition towards methanogenic activity. However, knowledge as to how ammonia affects the methanogens is still limited. In this study, we cultured a multitrophic methanogen, Methanosarcina barkeri DSM 800, with acetate, H2/CO2, and methanol to evaluate the influence of ammonia on different methanogenic pathways. Aceticlastic methanogenesis was more sensitive to increased ammonia concentrations than hydrogenotrophic and methylotrophic methanogenesis. Theoretical maximum NH3 tolerances of M. barkeri fed with acetate, H2/CO2, and methanol were calculated to be 39.1 ± 9.0, 104.3 ± 7.4, and 85.7 ± 1.0 mg/L, respectively. The order of the ΔG range of M. barkeri under three methanogenic pathways reflected the order of ammonia tolerance of M. barkeri. Our results provide insights into the role of the thermodynamic potential of methanogenesis on the tolerance of ammonia stress; and shed light on the mechanism of ammonia inhibition on anaerobic digestion
Philanthropy and Socio-economic Development: The Role of Large Indigenous Voluntary Organizations in Bridging Social Divides in Pakistan
Full text linkExtant research has focused on the role of philanthropy in the socioeconomic development of western countries, but little is known about the role of indigenous voluntary organisations in bridging social divides in the developing world. To help redress this imbalance, we present findings on the motivations, strategies, methods, and impact of five large philanthropically funded voluntary organizations in Pakistan. We ask how and why such organizations are formed and gain traction to provide valuable services for large numbers of poor people in a society riddled with inequalities. Although differing considerably in their relations to markets and philanthropy, we find that success in all cases followed from commitment to Islamic philanthropy and the ideal of social inclusion, social innovation, exploitation of social capital, and scaling-up. Our contribution is to demonstrate how in developing countries philanthropy and social entrepreneurship together can play a decisive role in realizing a more just society
Machine learning-based identification and classification of physical fatigue levels: A novel method based on a wearable insole device
Full text linkConstruction is known for being a labor-intensive and risky industry. Within various occupational settings such as construction, physical fatigue is an underlying health condition that may lead to musculoskeletal disorders and fall-related injuries. Identifying a worker's physical fatigue could enable safety managers to mitigate fatigue-related injuries and improve workplace operations. However, current physical fatigue assessment and identification methods include subjective, physiological, biomechanical, and computer vision approaches, which may be unreliable, intrusive, and require extensive post-processing, thus, rendering them impractical for continuous monitoring of workers' movements and automated identification of physical fatigue. Given the above, this study aims to utilize a wearable insole device to identify and classify physical fatigue levels in construction workers. Ten asymptomatic subjects were recruited to perform a fatiguing manual rebar tying activity in a laboratory setting. Borg's rating of perceived exertion (RPE) was applied as a subjective measure for collecting the levels of physical fatigue of each subject. Three sub-classification problems for identifying physical fatigue levels (i.e., PFL1, PFL2, and PFL3) were assessed. Numerous features were evaluated from the collected data samples after data segmentation. The classification performance of supervised machine learning algorithms was evaluated at a sliding window of 2.56 s. Our results from 10-fold cross-validation show an accuracy of 86% for the Random Forest (RF) algorithm, indicating the best performance among other algorithms. In addition, precision, recall, specificity, and F1-score metrics of the RF algorithm were between 52.63% and 82.62%, 52.63%–84.32%, 89.60%–92.33%, and 52.63%–83.46%, respectively. These results indicate that data samples such as acceleration and plantar pressure acquired from a wearable insole device are reliable for identifying and classifying physical fatigue levels in construction workers. In summary, this study would contribute to providing a proactive physical fatigue assessment method and guidelines for early identification of physical fatigue in construction
A potential well model for host-guest chemistry in double-network hydrogels toward mechanochemical coupling and toughening
Full text linkDifferent from the conventional single-network hydrogels, double-network (DN) hydrogels have attracted great research interest due to their ultra-high toughness, however, their working principles behind complex mechanochemical coupling have not been fully understood. In this study, an extended potential well model is formulated to investigate host-guest chemistry and free-energy trap effect, coupled in the DN hydrogels undergoing mechanochemical toughening. According to the Morse potential and mean field model, the newly established potential well model can describe the coupled binding of host brittle network and guest ductile network in the DN hydrogels. A free-energy equation is further proposed to describe working principles of mechanochemical coupling and toughening mechanisms using the depth, width and trap number of potential wells, which determine the barrier energy of host brittle network, mesh size of guest ductile network and mechanochemical host-guest interactions of these two networks, respectively. Finally, effectiveness of the proposed model is verified using finite-element analysis and experimental results of various DN hydrogels reported in literature. This study clarifies the linking of mechanochemical coupling and toughening mechanisms in DN hydrogels having the host-guest chemistry from both brittle and ductile networks using the potential well model
Family Hubs and the vulnerable care ecologies of child and family welfare in austerity
Full text linkThis article takes an ecological approach to examine the legacies of austerity for local authority welfare systems in England and the implications for families seeking to use these services. Programmes of Early Intervention or Early Help that promote ‘resilience’ amongst marginalised families and reduce future dependency upon state services have been advocated consistently in the UK, currently intensifying with a period of welfare retrenchment and restructuring. Many programmes and approaches being promoted prioritise a discourse of individual or familial responsibility and seek to deflect attention away from structural and environmental changes that have taken place. We explore local authority family and child support services as relational care practices that have been fundamentally reshaped through austerity, and in doing so we seek to shift the conversation from individual responsibility to systemic and collective vulnerabilities. Drawing on the concept of ‘care ecology’ to conceptualise local authority Early Help services as ‘carescapes’, we focus specifically on the changing context of ‘Family Hubs’, and the fragmented nature of service provision. As with any ecosystem, care ecologies are constituted by interconnected and interdependent actors, processes and systems. Damage to them produces unintended consequences which exacerbate underlying ‘vulnerabilities’. We explore this as a legacy of austerity, noting that this has resulted in forms of socio-spatial distancing from care provision for families, disrupting protective networks and support systems. We argue that local authority support services would be better focused on systemic and collective vulnerabilities rather than individual responsibilities in order to provide meaningful support to families
Deformation and fracture mechanisms of selective laser melted tungsten skeleton reinforced copper matrix composites at varied temperatures
Full text linkTungsten skeleton reinforced copper matrix composites (TRC) were designed and fabricated using a selective laser melting (SLM) method followed by infiltration sintering. Deformation and fracture mechanisms were investigated at 25, 300 and 500 °C. Compressive and tensile tests of the tungsten skeletons showed brittle fracture mode, whereas tensile tests of the TRC exhibited a mixed mode of ductile and brittle fracture. Fracture mechanisms of the TRC were identified as cleavage of tungsten and separation between copper and tungsten at 25 °C. Whereas at 300 and 500 °C, its fracture mechanisms were identified as intergranular fracture of tungsten particles, tearing of copper and separation between copper and tungsten