187 research outputs found
Environmental Risk Explored Through Oil Spills and Hydraulic Fracturing: Attempting Environmental Protection through Policy
History demonstrates the dangers of ignoring the environmental risks that correspond to resource extraction, especially in precarious locations. This project analyzed three cases: (1) the 1989 Exxon Valdez oil spill, (2) the 2010 Deepwater Horizon oil spill, and (3) the current question of hydraulic fracturing in New York’s Marcellus Shale. The case studies assessed whether policies for protecting the environment from the risks of human activity have improved and whether such policies can be made both economically efficient and environmentally less risky. While the Exxon Valdez case demonstrated the dangers of not planning for disaster, it did result in the 1990 Oil Pollution Act [OPA]. Although OPA is requiring BP to fund cleanup of the Deepwater Horizon spill, OPA alone did little to prevent this event from happening. Using these historical examples, New York now has a chance to put better policies in place for the risk-laden technique of hydraulic fracturing. Economic pressures mean hydraulic fracturing is almost a certainty. This project argues that the State must require that extremely precautionary policies and strict regulations be implemented before drilling
A neuromuscular respiratory outpatient clinic: Patient profile and experience (Beaumont Hospital)
Accurate Hartree-Fock energy of extended systems using large Gaussian basis sets
Calculating highly accurate thermochemical properties of condensed matter via
wave function-based approaches (such as e.g. Hartree-Fock or hybrid
functionals) has recently attracted much interest. We here present two
strategies providing accurate Hartree-Fock energies for solid LiH in a large
Gaussian basis set and applying periodic boundary conditions. The total
energies were obtained using two different approaches, namely a supercell
evaluation of Hartree-Fock exchange using a truncated Coulomb operator and an
extrapolation toward the full-range Hartree-Fock limit of a Pad\'e fit to a
series of short-range screened Hartree-Fock calculations. These two techniques
agreed to significant precision. We also present the Hartree-Fock cohesive
energy of LiH (converged to within sub-meV) at the experimental equilibrium
volume as well as the Hartree-Fock equilibrium lattice constant and bulk
modulus.Comment: 7.5 pages, 2 figures, submitted to Phys. Rev. B; v2: typos removed,
References adde
Using metallic noncontact atomic force microscope tips for imaging insulators and polar molecules: tip characterization and imaging mechanisms
We demonstrate that using metallic tips for noncontact atomic force microscopy (NC-AFM) imaging at relatively large (>0.5 nm) tip-surface separations provides a reliable method for studying molecules on insulating surfaces with chemical resolution and greatly reduces the complexity of interpreting experimental data. The experimental NC-AFM imaging and theoretical simulations were carried out for the NiO(001) surface as well as adsorbed CO and Co-Salen molecules using Cr-coated Si tips. The experimental results and density functional theory calculations confirm that metallic tips possess a permanent electric dipole moment with its positive end oriented toward the sample. By analyzing the experimental data, we could directly determine the dipole moment of the Cr-coated tip. A model representing the metallic tip as a point dipole is described and shown to produce NC-AFM images of individual CO molecules adsorbed onto NiO(001) in good quantitative agreement with experimental results. Finally, we discuss methods for characterizing the structure of metal-coated tips and the application of these tips to imaging dipoles of large adsorbed molecules. © 2014 American Chemical Society
Support for smoke-free policy, and awareness of tobacco health effects and use of smoking cessation therapy in a developing country
BACKGROUND: Preventing an epidemic increase in smoking prevalence is a major challenge for developing countries. Ghana, has maintained a low smoking prevalence despite the presence of cigarette manufacturing for many decades. Some of this success may have been contributed by cultural factors and attitudes. We have studied public awareness of health risks, attitudes to smoke-free policy, tobacco advertising/promotion and other factors in a Ghanaian population sample. METHODS: We used two-stage cluster randomized sampling to study household members aged 14 and over in a representative household sample in the Ashanti Region of Ghana. RESULTS: 6258 people, 88% of those eligible, took part in the study. Knowledge of health risks of smoking and passive smoking was high; radio was the main source of such information. Most people work and/or spend time in places where smoking is permitted. There was very strong support (97%) for comprehensive smoke-free legislation, particularly among Christians and Muslims. Despite the advertising ban, a third of respondents (35%), particularly in urban areas, had noticed advertising of tobacco or tobacco products, on the radio (72%) and television (28%). Among smokers, 76% had attempted to quit in the last 6 months, with the main sources of advice being friends and spouses. Use of nicotine replacement therapy was very rare. Low levels of health awareness were seen in females compared with males (Adjusted Odds Ratio (AOR); 0.51, 95% CI 0.39-0.69, p < 0.001). High levels of health awareness was seen among Traditionalists compared with Christians AOR; 2.16 95% CI 0.79-5.94, p < 0.05) and the relatively well educated (AOR; 1.70 95% CI 1.12-2.58, p < 0.05) and those living in rural areas (AOR 1.46 95% CI 1.14-1.87, p = 0.004). CONCLUSION: Awareness of health risks and support for smoke-free policy are high in Ghana. Exposure to tobacco advertising or promotion is limited and most smokers have tried to quit. Whether these findings are cause or effect of current low smoking prevalence is uncertain
On the Zwitterionic Nature of Gas-Phase Peptides and Protein Ions
Determining the total number of charged residues corresponding to a given value of net charge for peptides and proteins in gas phase is crucial for the interpretation of mass-spectrometry data, yet it is far from being understood. Here we show that a novel computational protocol based on force field and massive density functional calculations is able to reproduce the experimental facets of well investigated systems, such as angiotensin II, bradykinin, and tryptophan-cage. The protocol takes into account all of the possible protomers compatible with a given charge state. Our calculations predict that the low charge states are zwitterions, because the stabilization due to intramolecular hydrogen bonding and salt-bridges can compensate for the thermodynamic penalty deriving from deprotonation of acid residues. In contrast, high charge states may or may not be zwitterions because internal solvation might not compensate for the energy cost of charge separation
Fifteen species in one: deciphering the Brachionus plicatilis species complex (Rotifera, Monogononta) through DNA taxonomy
Understanding patterns and processes in biological diversity is a critical task given current and rapid environmental change. Such knowledge is even more essential when the taxa under consideration are important ecological and evolutionary models. One of these cases is the monogonont rotifer cryptic species complex Brachionus plicatilis, which is by far the most extensively studied group of rotifers, is widely used in aquaculture, and is known to host a large amount of unresolved diversity. Here we collate a dataset of previously available and newly generated sequences of COI and ITS1 for 1273 isolates of the B. plicatilis complex and apply three approaches in DNA taxonomy (i.e. ABGD, PTP, and GMYC) to identify and provide support for the existence of 15 species within the complex. We used these results to explore phylogenetic signal in morphometric and ecological traits, and to understand correlation among the traits using phylogenetic comparative models. Our results support niche conservatism for some traits (e.g. body length) and phylogenetic plasticity for others (e.g. genome size)
The neurology of COVID-19 revisited: A proposal from the environmental neurology specialty group of the world federation of neurology to implement international neurological registries
A comprehensive review of the neurological disorders reported during the current COVID-19 pandemic demonstrates that infection with SARS-CoV-2 affects the central nervous system (CNS), the peripheral nervous system (PNS) and the muscle. CNS manifestations include: headache and decreased responsiveness considered initial indicators of potential neurological involvement; anosmia, hyposmia, hypogeusia, and dysgeusia are frequent early symptoms of coronavirus infection. Respiratory failure, the lethal manifestation of COVID-19, responsible for 264,679 deaths worldwide, is probably neurogenic in origin and may result from the viral invasion of cranial nerve I, progressing into rhinencephalon and brainstem respiratory centers. Cerebrovascular disease, in particular large-vessel ischemic strokes, and less frequently cerebral venous thrombosis, intracerebral hemorrhage and subarachnoid hemorrhage, usually occur as part of a thrombotic state induced by viral attachment to ACE2 receptors in endothelium causing widespread endotheliitis, coagulopathy, arterial and venous thromboses. Acute hemorrhagic necrotizing encephalopathy is associated to the cytokine storm. A frontal hypoperfusion syndrome has been identified. There are isolated reports of seizures, encephalopathy, meningitis, encephalitis, and myelitis. The neurological diseases affecting the PNS and muscle in COVID-19 are less frequent and include Guillain-Barré syndrome; Miller Fisher syndrome; polyneuritis cranialis; and rare instances of viral myopathy with rhabdomyolysis. The main conclusion of this review is the pressing need to define the neurology of COVID-19, its frequency, manifestations, neuropathology and pathogenesis. On behalf of the World Federation of Neurology we invite national and regional neurological associations to create local databases to report cases with neurological manifestations observed during the on-going pandemic. International neuroepidemiological collaboration may help define the natural history of this worldwide problem
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