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Waste management, informal recycling, environmental pollution and public health
With rapid population growth, especially in low-income and middle-income countries, the generation of waste is increasing at an unprecedented rate. For example, annual global waste arising from waste electrical and electronic equipment alone will have increased from 33.8 to 49.8 million tonnes between 2010 and 2018. Despite incineration and other waste treatment techniques, landfill still dominates waste disposal in low-income and middle-income countries. There is usually insufficient funding for adequate waste management in these countries and uptake of more advanced waste treatment technologies is poor. Without proper management, many landfills represent serious hazards as typified by the landslide in Shenzhen, China on 20 December 2015. In addition to formal waste recycling systems, approximately 15 million people around the world are involved in informal waste recycling, mainly for plastics, metals, glass and paper. This review examines emerging public health challenges, in particular within low-income and middle-income countries, associated with the informal sector. While informal recyclers contribute to waste recycling and reuse, the relatively primitive techniques they employ, combined with improper management of secondary pollutants, exacerbate environmental pollution of air, soil and water. Even worse, insufficient occupational health measures expose informal waste workers to a range of pollutants, injuries, respiratory and dermatological problems, infections and other serious health issues that contribute to low life expectancy. Integration of the informal sector with its formal counterparts could improve waste management while addressing these serious health and livelihood issues. Progress in this direction has already been made notably in several Latin American countries where integrating the informal and formal sectors has had a positive influence on both waste management and poverty alleviation
(±)-trans-3-Oxo-1,2,3,4,4a,9,10,10a-octaÂhydroÂphenanthrene-10a-carboxylic acid: catemeric hydrogen bonding in a δ-keto acid
The title compound, C15H16O3, aggregates as hydrogen-bonded catemers progressing from each carboxyl to the ketone of a screw-related neighbor [O⋯O = 2.6675 (14) Å and O—H⋯O = 170°]. Two parallel centrosymmetrically related single-strand hydrogen-bonding helices proceed through the cell in the b-axis direction. The packing includes three interÂmolecular C—H⋯O=C close contacts, involving both the ketone and the carboxyl group. The structure is isomorphous with that of the previously described Δ4 α,β-unsaturated ketone
Absolute radiometric calibration of the EUNIS-06 170-205 A channel and calibration update for CDS/NIS
The Extreme-Ultraviolet Normal-Incidence Spectrograph sounding-rocket payload
was flown on 2006 April 12 (EUNIS-06), carrying two independent imaging
spectrographs covering wave bands of 300-370 A in first order and 170-205 A in
second order, respectively. The absolute radiometric response of the EUNIS-06
long-wavelength (LW) channel was directly measured in the same facility used to
calibrate CDS prior to the SOHO launch. Because the absolute calibration of the
short-wavelength (SW) channel could not be obtained from the same lab
configuration, we here present a technique to derive it using a combination of
solar LW spectra and density- and temperature-insensitive line intensity
ratios. The first step in this procedure is to use the coordinated, cospatial
EUNIS and SOHO/CDS spectra to carry out an intensity calibration update for the
CDS NIS-1 waveband, which shows that its efficiency has decreased by a factor
about 1.7 compared to that of the previously implemented calibration. Then,
theoretical insensitive line ratios obtained from CHIANTI allow us to determine
absolute intensities of emission lines within the EUNIS SW bandpass from those
of cospatial CDS/NIS-1 spectra after the EUNIS LW calibration correction. A
total of 12 ratios derived from intensities of 5 CDS and 12 SW emission lines
from Fe Fe X - Fe XIII yield an instrumental response curve for the EUNIS-06 SW
channel that matches well to a relative calibration which relied on combining
measurements of individual optical components. Taking into account all
potential sources of error, we estimate that the EUNIS-06 SW absolute
calibration is accurate to about 20%.Comment: 11 pages, 10 figures, 4 tables. 2010, ApJ Suppl. In pres
FIRE Spectroscopy of Five Late-type T Dwarfs Discovered with the Wide-field Infrared Survey Explorer
We present the discovery of five late-type T dwarfs identified with the
Wide-field Infrared Survey Explorer (WISE). Low-resolution near-infrared
spectroscopy obtained with the Magellan Folded-port InfraRed Echellette (FIRE)
reveal strong water and methane absorption in all five sources, and spectral
indices and comparison to spectral templates indicate classifications ranging
from T5.5 to T8.5:. The spectrum of the latest-type source, WISE J1812+2721, is
an excellent match to that of the T8.5 companion brown dwarf Wolf 940B.
WISE-based spectrophotometric distance estimates place these T dwarfs at 12-13
pc from the Sun, assuming they are single. Preliminary fits of the spectral
data to the atmosphere models of Saumon & Marley indicate effective
temperatures ranging from 600 K to 930 K, both cloudy and cloud-free
atmospheres, and a broad range of ages and masses. In particular, two sources
show evidence of both low surface gravity and cloudy atmospheres, tentatively
supporting a trend noted in other young brown dwarfs and exoplanets. In
contrast, the high proper motion T dwarf WISE J2018-7423 exhibits a suppressed
K-band peak and blue spectrophotometric J-K colors indicative of an old,
massive brown dwarf; however, it lacks the broadened Y-band peak seen in
metal-poor counterparts. These results illustrate the broad diversity of
low-temperature brown dwarfs that will be uncovered with WISE.Comment: 19 pages, 13 figures; accepted for publication to Ap
Underflight calibration of SOHO/CDS and Hinode/EIS with EUNIS-07
Flights of Goddard Space Flight Center's Extreme-Ultraviolet Normal-Incidence
Spectrograph (EUNIS) sounding rocket in 2006 and 2007 provided updated
radiometric calibrations for SOHO/CDS and Hinode/EIS. EUNIS carried two
independent imaging spectrographs covering wavebands of 300-370 A in first
order and 170-205 A in second order. After each flight, end-to-end radiometric
calibrations of the rocket payload were carried out in the same facility used
for pre-launch calibrations of CDS and EIS. During the 2007 flight, EUNIS, SOHO
CDS and Hinode EIS observed the same solar locations, allowing the EUNIS
calibrations to be directly applied to both CDS and EIS. The measured CDS NIS 1
line intensities calibrated with the standard (version 4) responsivities with
the standard long-term corrections are found to be too low by a factor of 1.5
due to the decrease in responsivity. The EIS calibration update is performed in
two ways. One is using the direct calibration transfer of the calibrated
EUNIS-07 short wavelength (SW) channel. The other is using the insensitive line
pairs, in which one member was observed by EUNIS-07 long wavelength (LW)
channel and the other by EIS in either LW or SW waveband. Measurements from
both methods are in good agreement, and confirm (within the measurement
uncertainties) the EIS responsivity measured directly before the instrument's
launch. The measurements also suggest that the EIS responsivity decreased by a
factor of about 1.2 after the first year of operation. The shape of the EIS SW
response curve obtained by EUNIS-07 is consistent with the one measured in
laboratory prior to launch. The absolute value of the quiet-Sun He II 304 A
intensity measured by EUNIS-07 is consistent with the radiance measured by CDS
NIS in quiet regions near the disk center and the solar minimum irradiance
obtained by CDS NIS and SDO/EVE recently.Comment: 16 pages, 14 figures, 5 tables, accepted by ApJ Supplement (Sep.
2011
Use of ETC-1002 to treat hypercholesterolemia in patients with statin intolerance
BackgroundOnce-daily, oral ETC-1002 reduces low-density lipoprotein cholesterol (LDL-C) and has beneficial effects on other cardiometabolic risk factors but has not been examined in statin intolerant patients.ObjectivesTo study the efficacy and safety of ETC-1002 (a novel LDL-C–lowering agent) in patients with hypercholesterolemia and a history of statin intolerance.MethodsPatients intolerant to at least 1 statin were entered into this multicenter, double-blind, 8-week trial. Participants were required to have a history of muscle complaints that developed during statin treatment and resolved within 4 weeks of statin discontinuation. Patients (n = 56) were randomized in a 2:1 ratio to ETC-1002 60 mg daily or placebo. The ETC-1002 dose was increased at 2-week intervals to 120 mg, 180 mg, and 240 mg. The primary end point was the percentage change from baseline to week 8 in calculated LDL-C.ResultsETC-1002 reduced LDL-C 28.7% more than placebo (95% confidence interval, −35.4 to −22.1; P < .0001). ETC-1002 significantly reduced non–high-density lipoprotein cholesterol, total cholesterol, apolipoprotein B, and high-sensitivity C-reactive protein. Triglycerides and high-density lipoprotein cholesterol did not change with ETC-1002 treatment. Sixty-two percent of patients receiving ETC-1002 and none in the placebo group achieved the 2004 National Cholesterol Education Program Adult Treatment Panel III LDL-C goal (P < .0001). Muscle-related adverse events occurred with similar frequency in the placebo and ETC-1002 treatment groups, causing no discontinuations in ETC-1002–treated patients.ConclusionsETC-1002 appears to be effective at reducing LDL-C and was well tolerated in patients with statin-associated muscle complaints. Longer and larger studies are required to confirm the absence of muscle side effects
Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30 day outcomes from IMPROVE randomised trial.
OBJECTIVE: To assess whether a strategy of endovascular repair (if aortic morphology is suitable, open repair if not) versus open repair reduces early mortality for patients with suspected ruptured abdominal aortic aneurysm. DESIGN: Randomised controlled trial. SETTING: 30 vascular centres (29 UK, 1 Canadian), 2009-13. PARTICIPANTS: 613 eligible patients (480 men) with a clinical diagnosis of ruptured aneurysm. INTERVENTIONS: 316 patients were randomised to the endovascular strategy (275 confirmed ruptures, 174 anatomically suitable for endovascular repair) and 297 to open repair (261 confirmed ruptures). MAIN OUTCOME MEASURES: 30 day mortality, with 24 hour and in-hospital mortality, costs, and time and place of discharge as secondary outcomes. RESULTS: 30 day mortality was 35.4% (112/316) in the endovascular strategy group and 37.4% (111/297) in the open repair group: odds ratio 0.92 (95% confidence interval 0.66 to 1.28; P=0.62); odds ratio after adjustment for age, sex, and Hardman index 0.94 (0.67 to 1.33). Women may benefit more than men (interaction test P=0.02) from the endovascular strategy: odds ratio 0.44 (0.22 to 0.91) versus 1.18 (0.80 to 1.75). 30 day mortality for patients with confirmed rupture was 36.4% (100/275) in the endovascular strategy group and 40.6% (106/261) in the open repair group (P=0.31). More patients in the endovascular strategy than in the open repair group were discharged directly to home (189/201 (94%) v 141/183 (77%); P<0.001). Average 30 day costs were similar between the randomised groups, with an incremental cost saving for the endovascular strategy versus open repair of £1186 (€1420; $1939) (95% confidence interval -£625 to £2997). CONCLUSIONS: A strategy of endovascular repair was not associated with significant reduction in either 30 day mortality or cost. Longer term cost effectiveness evaluations are needed to assess the full effects of the endovascular strategy in both men and women. TRIAL REGISTRATION: Current Controlled Trials ISRCTN48334791
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