1,753 research outputs found
Cultivating Sustainable Coffee: Persistent Paradoxes
This chapter discusses the relationship and interconnections among changing the livelihoods of farmers, initiatives for sustainable coffee, and the production of shade-grown coffee. It examines the advantages and opportunities for farmers and producers engaged in coffee certification and diversification programs. The role of Fair Trade and organic networks in creating awareness of biodiversity conservation, the social and environment costs of coffee systems, and the need for supporting small farmers are also discussed. The methods to increase accountability and improve the efficiency of coffee cooperatives are presented in this chapter, as are the importance of understanding the sustainability initiatives and their implications for the regulators, along with the use of land patterns for coffee cultivation
An exploration of barriers and facilitators to older adultsâ participation in higher impact physical activity and bone health:a qualitative study
The survival advantage of pancreas after kidney transplant
Patient survival after pancreas after kidney transplant (PAK) has been reported to be inferior to patient survival after simultaneous pancreasâkidney transplant (SPK). The authors examine national data to further explore allograft (kidney and pancreas) and patient survival after PAK. KaplanâMeier and Cox proportional hazard models were used to analyze Organ Procurement and Transplantation Network data from 1995 to 2010. The analysis compared PAK and SPK candidates and recipients. KaplanâMeier analysis results showed that PAK after either a living or a deceased donor kidney transplant is associated with increased kidney graft survival compared with recipients with type 1 diabetes who received only a kidney. The best kidney allograft survival was for patients who received a living donor kidney followed by PAK. Receiving a living donor kidney was associated with increased pancreas allograft survival compared with receiving a deceased donor kidney. PAK transplant recipients who receive both organs have a survival advantage compared with uremic candidates who receive neither (SPK waitlist). Compared with uremic diabetic waitlist patients, SPK and PAK recipients showed similar overall patient survival. Successful PAK offers a survival advantage compared with receiving neither a kidney nor a pancreas transplant. These data also suggest that receiving a pancreas (after kidney) transplant may have a protective effect on the kidney allograft
IridiumâCatalysed CâH Borylation of Fluoroarenes: Insights into the Balance between Steric and Electronic Control of Regioselectivity
The iridium catalysed CâH borylation of polyfluorinated arenes and heteroarenes occurs rapidly and efficiently. As with other borylation reactions, whilst steric parameters dominate, an underlying electronic influence on reaction selectivity can be observed. Notably borylation regioselectivity in fluorinated (hetero)arenes is determined by purely electronic effects except for ortho-borylation between two fluorine atoms where steric effects of fluorine substituents become apparent. Borylation at the para position with respect to fluorine is disfavoured whereas a strong electronic preference for borylation para to the azinyl nitrogen of pyridine is observed. When these features co-operate high selectivity can be expected. For these reactions, computations based on transition state, rather than intermediate, energies in iridium geometries showed excellent agreement between predicted and observed selectivities
Strongly minimal PD4-complexes
We consider the homotopy types of -complexes with fundamental group
such that and has one end. Let
and . Our main result is that (modulo two technical conditions on
) there are at most orbits of -invariants determining
"strongly minimal" complexes (i.e., those with homotopy intersection pairing
trivial). The homotopy type of a -complex with a
-group is determined by , , and the -type of
. Our result also implies that Fox's 2-knot with metabelian group is
determined up to TOP isotopy and reflection by its group.Comment: 17 page
Structure and hydration of polyvinylpyrrolidone-hydrogen peroxide
The structure of the commercially important polyvinylpyrrolidone-hydrogen peroxide complex can be understood by reference to the co-crystal structure of a hydrogen peroxide complex and its mixed hydrates of a two-monomer unit model compound, bisVP·2H2O2. The mixed hydrates involve selective water substitution into one of the two independent hydrogen peroxide binding sites
Perinatal assessment of complex cesarean delivery: beyond placenta accreta spectrum
Multiple cesarean deliveries are known to be associated with long-term postoperative consequences because of a permanent defect of the lower uterine segment wall and the development of thick pelvic adhesions. Patients with a history of multiple cesarean deliveries often present with large cesarean scar defects and are at heightened risk in subsequent pregnancies of cesarean scar ectopic pregnancy, uterine rupture, low-lying placenta or placenta previa, and placenta previa accreta. Moreover, large cesarean scar defects will lead to progressive dehiscence of the lower uterine segment with the inability to effectively reapproximate hysterotomy edge and repair at birth. Major remodeling of the lower uterine segment associated with true placenta accreta spectrum at birth, whereby the placenta becomes inseparable from the uterine wall, increases the rates of perinatal morbidity and mortality, especially when undiagnosed before delivery. Ultrasound imaging is currently not routinely used to evaluate the surgical risks of patients with a history of multiple cesarean deliveries, beyond the risk assessment of placenta accreta spectrum. Independent of accreta placentation, a placenta previa under a scarred, thinned partially disrupted lower uterine segment, covered by thick adhesions with the posterior wall of the bladder, poses a surgical risk and requires fine dissection and surgical expertise; however, data on the use of ultrasound to evaluate uterine remodeling and adhesions between the uterus and other pelvic organs are scarce. In particular, transvaginal sonography has been underused, including in patients with a high probability of placenta accreta spectrum at birth. Based on the best available knowledge, we discuss the role of ultrasound imaging in identifying the signs suggestive of major remodeling of the lower uterine segment and in mapping the changes in the uterine wall and pelvis, to enable the surgical team to prepare for all different types of complex cesarean deliveries. The need for postnatal confirmation of the prenatal ultrasound findings for all patients with a history of multiple cesarean deliveries, regardless of the diagnosis of placenta previa and placenta accreta spectrum, is discussed. We propose an ultrasound imaging protocol and a classification of the level of surgical difficulty at elective cesarean delivery to stimulate further research toward the validation of ultrasound signs by which these signs may be applied to improve surgical outcomes
Toward cyberinfrastructure to facilitate collaboration and reproducibility for marine integrated ecosystem assessments
Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Earth Science Informatics 10 (2017): 85-97, doi:10.1007/s12145-016-0280-4.There is a growing need for cyberinfrastructure to support science-based decision making in management of natural resources. In particular, our motivation was to aid the development of cyberinfrastructure for Integrated Ecosystem Assessments (IEAs) for marine ecosystems. The IEA process involves analysis of natural and socio-economic information based on diverse and disparate sources of data, requiring collaboration among scientists of many disciplines and communication with other stakeholders. Here we describe our bottom-up approach to developing cyberinfrastructure through a collaborative process engaging a small group of domain and computer scientists and software engineers. We report on a use case evaluated for an Ecosystem Status Report, a multi-disciplinary report inclusive of Earth, life, and social sciences, for the Northeast U.S. Continental Shelf Large Marine Ecosystem. Ultimately, we focused on sharing workflows as a component of the cyberinfrastructure to facilitate collaboration and reproducibility. We developed and deployed a software environment to generate a portion of the Report, retaining traceability of derived datasets including indicators of climate forcing, physical pressures, and ecosystem states. Our solution for sharing workflows and delivering reproducible documents includes IPython (now Jupyter) Notebooks. We describe technical and social challenges that we encountered in the use case and the importance of training to aid the adoption of best practices and new technologies by domain scientists. We consider the larger challenges for developing end-to-end cyberinfrastructure that engages other participants and stakeholders in the IEA process.Support for this research was provided by the U. S. National Science Foundation #0955649 with additional support to SB by the Investment in Science Fund at Woods Hole Oceanographic Institution
Relationships between Larval and Juvenile Abundance of Winter-Spawned Fishes in North Carolina, USA
We analyzed the relationships between the larval and juvenile abundances of selected estuarine-dependent fishes that spawn during the winter in continental shelf waters of the U.S. Atlantic coast. Six species were included in the analysis based on their ecological and economic importance and relative abundance in available surveys: spot Leiostomus xanthurus, pinfish Lagodon rhomboides, southern flounder Paralichthys lethostigma, summer flounder Paralichthys dentatus, Atlantic croaker Micropogonias undulatus, and Atlantic menhaden Brevoortia tyrannus. Cross-correlation analysis was used to examine the relationships between the larval and juvenile abundances within species. Tests of synchrony across species were used to find similarities in recruitment dynamics for species with similar winter shelf-spawning life-history strategies. Positive correlations were found between the larval and juvenile abundances for three of the six selected species (spot, pinfish, and southern flounder). These three species have similar geographic ranges that primarily lie south of Cape Hatteras. There were no significant correlations between the larval and juvenile abundances for the other three species (summer flounder, Atlantic croaker, and Atlantic menhaden); we suggest several factors that could account for the lack of a relationship. Synchrony was found among the three southern species within both the larval and juvenile abundance time series. These results provide support for using larval ingress measures as indices of abundance for these and other species with similar geographic ranges and winter shelf-spawning life-history strategies
Helicobacter pylori-induced gastric pathology: insights from in vivo and ex vivo models
Gastric colonization with Helicobacter pylori induces diverse human pathological conditions, including superficial gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric adenocarcinoma and its precursors. The treatment of these conditions often relies on the eradication of H. pylori, an intervention that is increasingly difficult to achieve and that does not prevent disease progression in some contexts. There is, therefore, a pressing need to develop new experimental models of H. pylori-associated gastric pathology to support novel drug development in this field. Here, we review the current status of in vivo and ex vivo models of gastric H. pylori colonization, and of Helicobacter-induced gastric pathology, focusing on models of gastric pathology induced by H. pylori, Helicobacter felis and Helicobacter suis in rodents and large animals. We also discuss the more recent development of gastric organoid cultures from murine and human gastric tissue, as well as from human pluripotent stem cells, and the outcomes of H. pylori infection in these systems
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