Institutional work focuses on the role of actors in creating, maintaining, or disrupting institutional structures. The concept has its origin in organisational studies. In this paper, we rethink and ...redefine institutional work to make it fit for use in the multi-actor and multi-level context of environmental governance. We survey key approaches to institutional change in the literature, and argue that institutional work should have a central place within this theorising. Drawing on the insights from this literature, we argue that studying institutional work should involve a look at both the actions taken by actors, as well as the resulting effects. We identify a critical need for attention to the fundamentally political character of institutional work, the cumulative effects of action taken by multiple actors, and communicative and discursive dimensions. Overall, the concept of institutional work opens up new possibilities for unpacking the longstanding challenge of understanding institutional change in environmental governance.
Searching for genetic variants with unusual differentiation between subpopulations is an established approach for identifying signals of natural selection. However, existing methods generally require ...discrete subpopulations. We introduce a method that infers selection using principal components (PCs) by identifying variants whose differentiation along top PCs is significantly greater than the null distribution of genetic drift. To enable the application of this method to large datasets, we developed the FastPCA software, which employs recent advances in random matrix theory to accurately approximate top PCs while reducing time and memory cost from quadratic to linear in the number of individuals, a computational improvement of many orders of magnitude. We apply FastPCA to a cohort of 54,734 European Americans, identifying 5 distinct subpopulations spanning the top 4 PCs. Using the PC-based test for natural selection, we replicate previously known selected loci and identify three new genome-wide significant signals of selection, including selection in Europeans at ADH1B. The coding variant rs1229984∗T has previously been associated to a decreased risk of alcoholism and shown to be under selection in East Asians; we show that it is a rare example of independent evolution on two continents. We also detect selection signals at IGFBP3 and IGH, which have also previously been associated to human disease.
Abstract Bioactive hydrogels formed by Michael-type addition reactions of end-functionalized poly(ethylene glycol) macromers with cysteine-containing peptides have been described as extracellular ...matrix mimetics and tissue engineering scaffolds. Although these materials have shown favorable behavior in vivo in tissue repair, we sought to develop materials formulations that would be more rapidly responsive to cell-induced enzymatic remodeling. In this study, protease-sensitive peptides that have increased kcat values were characterized and evaluated for their effects on gel degradability. Biochemical properties for soluble peptides and hydrogels were examined for matrix metalloproteinase (MMP)-1 and MMP-2. The most efficient peptide substrates in some cases overlap and in other cases differ between the two enzymes tested, and a range of kcat values was obtained. For each enzyme, hydrogels formed using the peptides with higher kcat values degraded faster than a reference with lower kcat . Fibroblasts showed increased cell spreading and proliferation when cultured in 3D hydrogels with faster degrading peptides, and more cell invasion from aortic ring segments embedded in the hydrogels was observed. These faster degrading gels should provide matrices that are easier for cells to remodel and lead to increased cellular infiltration and potentially more robust healing in vivo.
This study investigates the mean concentration and characteristics of macroplastics (>2.5 cm), mesoplastics (5 mm - 2.5 cm) and microplastics (<5 mm) on eight sandy beaches along the shoreline of ...Tuticorin, Tamil Nadu. Prevalence of plastic litters varies among the study sites depending on the intensity of fishing and other human activities. Mean concentrations of macroplastics (1.38 ± 78 to 6.16 ± 94 items/m2), mesoplastics (2 ± 0.8 to 17 ± 0.11 items/m2) and microplastics (25 ± 1.58 to 83 ± 49 items/m2) were estimated in respect of the polymers composing them namely PE, PP, PET, NY, PS and PVC, of which PE is the most predominant polymer. At Sites 1, 2, 3, 5 and 8 there is correlation between the intensity of fishing activity and the concentrations of macro- (p = 0.02) and microplastics (p = 0.03). Sites 4, 6 and 7 there is correlation established between the degree of recreational activity and the concentrations of meso- (p = 0.02) and microplastics (p = 0.01).
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•Prevalence of macro-, meso-, and microplastics were studied 8 beaches along the Tuticorin coast.•Their mean concentrations are 1.38 ± 78 to 6.16 ± 94, 2 ± 0.8 to 17 ± 0.11 and 25 ± 1.58 to 83 ± 49 items/m2.•The common polymers found are PE, PP, PET, NY, PS and PVC.•There is strong correlation between the concentrations of micro- and mesoplastics.
Fetal hearts show a remarkable ability to develop under hypoxic conditions. The metabolic flexibility of fetal hearts allows sustained development under low oxygen conditions. In fact, hypoxia is ...critical for proper myocardial formation. Particularly, hypoxia inducible factor 1 (HIF-1) and vascular endothelial growth factor play central roles in hypoxia-dependent signaling in fetal heart formation, impacting embryonic outflow track remodeling and coronary vessel growth. Although HIF is not the only gene involved in adaptation to hypoxia, its role places it as a central figure in orchestrating events needed for adaptation to hypoxic stress. Although "normal" hypoxia (lower oxygen tension in the fetus as compared with the adult) is essential in heart formation, further abnormal hypoxia in utero adversely affects cardiogenesis. Prenatal hypoxia alters myocardial structure and causes a decline in cardiac performance. Not only are the effects of hypoxia apparent during the perinatal period, but prolonged hypoxia in utero also causes fetal programming of abnormality in the heart's development. The altered expression pattern of cardioprotective genes such as protein kinase c epsilon, heat shock protein 70, and endothelial nitric oxide synthase, likely predispose the developing heart to increased vulnerability to ischemia and reperfusion injury later in life. The events underlying the long-term changes in gene expression are not clear, but likely involve variation in epigenetic regulation.
Reduction in the impact of human-induced factors is capable of enhancing the environmental health. In view of COVID-19 pandemic, lockdowns were imposed in India. Travel, fishing, tourism and ...religious activities were halted, while domestic and industrial activities were restricted. Comparison of the pre- and post-lockdown data shows that water parameters such as turbidity, nutrient concentration and microbial levels have come down from pre- to post-lockdown period, and parameters such as dissolved oxygen levels, phytoplankton and fish densities have improved. The concentration of macroplastics has also dropped from the range of 138 ± 4.12 and 616 ± 12.48 items/100 m2 to 63 ± 3.92 and 347 ± 8.06 items/100 m2. Fish density in the reef areas has increased from 406 no. 250 m−2 to 510 no. 250 m−2. The study allows an insight into the benefits of effective enforcement of various eco-protection regulations and proper management of the marine ecosystems to revive their health for biodiversity conservation and sustainable utilization.
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•Study tracked the impact of COVID-19 lockdown on coastal environmental health•Improved water quality lead to higher productivity, lower microbial and heavy metal levels•Mean macroplastic concentration fell from 344.63± 58.47 to 177.75±41.78 items/100m2•Fish density increased from 406 to 510 no.250 m-2 during lockdown•Number of the ecologically important parrotfishes rose from 56 to 88 no.250 m-2
Concerning the theory of workload control Fredendall, Lawrence D.; Ojha, Divesh; Wayne Patterson, J.
European journal of operational research,
02/2010, Letnik:
201, Številka:
1
Journal Article
Recenzirano
An existing taxonomy of workload control rules is adapted to classify 25 workload control rules and their components examined in prior research to create a basis to model how three workload control ...rule components – order selection, work aggregation and buffer limits – affect shop performance in environments that differ in their bottleneck utilization and protective capacity levels. Two of the most frequently studied rules in the literature – CONWIP and DBR – were included in the simulation. Data analysis found that the workload control rules had a significant positive effect on the shop performance measures only in environments with the highest bottleneck utilization and the lowest protective capacity. However, the work aggregation method was found to be an important component of the workload control rule. Suggestions were made for future research that could increase our understanding of workload control rules and integrate this research with our understanding of lean production.
The sensitivity of organic–inorganic perovskites to environmental factors remains a major barrier for these materials to become commercially viable for photovoltaic applications. In this work, the ...degradation of formamidinium lead iodide (FAPbI3) perovskite in a moist environment is systematically investigated. It is shown that the level of relative humidity (RH) is important for the onset of degradation processes. Below 30% RH, the black phase of the FAPbI3 perovskite shows excellent phase stability over 90 d. Once the RH reaches 50%, degradation of the FAPbI3 perovskite occurs rapidly. Results from a Kelvin probe force microscopy study reveal that the formation of nonperovskite phases initiates at the grain boundaries and the phase transition proceeds toward the grain interiors. Also, ion migration along the grain boundaries is greatly enhanced upon degradation. A post‐thermal treatment (PTT) that removes chemical residues at the grain boundaries which effectively slows the degradation process is developed. Finally, it is demonstrated that the PTT process improves the performance and stability of the final device.
Moisture‐induced degradation of FAPbI3 perovskite is systematically investigated. A Kelvin probe force microscopy study reveals that the formation of nonperovskite phases initiates at the grain boundaries and the phase transition proceeds toward the grain interiors. A post‐thermal treatment that removes chemical residues at the grain boundaries which effectively slows the degradation process is developed.
Guidelines strongly recommend patients with heart failure with reduced ejection fraction (HFrEF) be treated with multiple medications proven to improve clinical outcomes, as tolerated. The degree to ...which gaps in medication use and dosing persist in contemporary outpatient practice is unclear.
This study sought to characterize patterns and factors associated with use and dose of HFrEF medications in current practice.
The CHAMP-HF (Change the Management of Patients with Heart Failure) registry included outpatients in the United States with chronic HFrEF receiving at least 1 oral medication for management of HF. Patients were characterized by baseline use and dose of angiotensin-converting enzyme inhibitor (ACEI)/angiotensin II receptor blocker (ARB), angiotensin receptor neprilysin inhibitor (ARNI), beta-blocker, and mineralocorticoid receptor antagonist (MRA). Patient-level factors associated with medication use were examined.
Overall, 3,518 patients from 150 primary care and cardiology practices were included. Mean age was 66 ± 13 years, 29% were female, and mean EF was 29 ± 8%. Among eligible patients, 27%, 33%, and 67% were not prescribed ACEI/ARB/ARNI, beta-blocker, and MRA therapy, respectively. When medications were prescribed, few patients were receiving target doses of ACEI/ARB (17%), ARNI (14%), and beta-blocker (28%), whereas most patients were receiving target doses of MRA therapy (77%). Among patients eligible for all classes of medication, 1% were simultaneously receiving target doses of ACE/ARB/ARNI, beta-blocker, and MRA. In adjusted models, older age, lower blood pressure, more severe functional class, renal insufficiency, and recent HF hospitalization generally favored lower medication utilization or dose. Social and economic characteristics were not independently associated with medication use or dose.
In this contemporary outpatient HFrEF registry, significant gaps in use and dose of guideline-directed medical therapy remain. Multiple clinical factors were associated with medication use and dose prescribed. Strategies to improve guideline-directed use of HFrEF medications remain urgently needed, and these findings may inform targeted approaches to optimize outpatient medical therapy.
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