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551.
As the impacts from anthropogenic climate change are increasing globally, people are experiencing dramatic shifts in weather, temperature, wildlife and vegetation patterns, and water and food quality and availability. These changes impact human health and well-being, and resultantly, climate change has been identified as the biggest global health threat of the 21st Century. Recently, research is beginning to indicate that changes in climate, and the subsequent disruption to the social, economic, and environmental determinants of health, may cause increased incidences and prevalence of mental health issues, emotional responses, and large-scale sociopsychological changes. Through a multi-year, community-led, exploratory case study conducted in Rigolet, Nunatsiavut, Labrador, Canada, this research qualitatively explores the impacts of climate change on mental health and well-being in an Inuit context. Drawing from 67 in-depth interviews conducted between January 2010 and October 2010 with community members and local and regional health professionals, participants reported that changes in weather, snow and ice stability and extent, and wildlife and vegetation patterns attributed to climate change were negatively impacting mental health and well-being due to disruptions in land-based activities and a loss of place-based solace and cultural identity. Participants reported that changes in climate and environment increased family stress, enhanced the possibility of increased drug and alcohol usage, amplified previous traumas and mental health stressors, and were implicated in increased potential for suicide ideation. While a preliminary case study, these exploratory findings indicate that climate change is becoming an additional mental health stressor for resource-dependent communities and provide a baseline for further research.  相似文献   
552.
We report the results of our population synthesis for post common-envelope binaries by following the evolution of each system in detail. Our main focus is a comparison with the white dwarf mass distribution of post common-envelope systems from the Sloan Digital Sky Survey. We employ a Monte Carlo method to choose the initial parameters of the progenitors (primary mass, mass ratio and orbital period). Then the evolution of the progenitor binary system is followed up to the onset of the common-envelope phase, which usually occurs near the tip of the giant branch or asymptotic giant branch. An approximate post-Helium flash evolution for primary masses ${\leq}2.25 \mathrm{M_{\odot}}$ is included. The binary parameters before and after common-envelope phase are calculated using the energy budget argument. In this paper we address the case of α CE=1.0, which is the commonly adopted value to calculate the common-envelope ejection. We consider a hydrogen-exhausted core to define the core mass of the primary (white dwarf mass, M WD) at the onset of common envelope phase. To obtain the present-day M WD distributions, we assumed a constant star formation rate. The distribution resulting from our population synthesis shows a double peak profile for M WD, similar to previous population syntheses and recent observational data. Our present synthesis result could not reproduce the location of the low and high mass peaks from the observations, but shows how a future synthesis can be made to produce an M WD distribution which is closer to observational data.  相似文献   
553.
554.
High resolution echelle spectroscopic observations taken with the FEROS spectrograph at the 2.2 m telescope ESO confirm the binary nature of the flare M3.5V star LU Vel (GJ 375, RE J0958-462) previously reported by Christian and Mathioudakis (2002). Emission of similar intensity from both components is detected in the Balmer, Na i D1&D2, He i D3, Ca ii H&K, and Ca ii IRT lines. We have determined precise radial velocities by cross correlation with radial velocity standard stars, which have allowed us to obtain for the first time the orbital solution of the system. The binary consists of two near-equal M3.5V components with an orbital period shorter than 2 days. We have analyzed the behaviour of the chromospheric activity indicators (variability and possible flares). In addition, we have determined its rotational velocity and kinematics.  相似文献   
555.
A rocket-borne coronagraph utilizing external occulting disks was used to photograph the solar corona from 3 to 9 R s at 1931 UT on 7 March, 1970. Comparison of the rocket and ground-based observations shows a one-to-one correspondence between major streamers from the inner to the outer corona. In particular streamers over the poles are clearly visible against the background corona from 3 to 8 R s. These rocket data had a scattered light level of 1.2 × 10–10 B s. The derived quiet equatorial and polar K + F corona was within 10% of the absolute brightness of standard coronal models and displayed identical radial gradients to those models. The photometric profiles of the NE limb streamer were analyzed assuming a model in which the core density follows a Gaussian distribution in directions perpendicular to the radius vector. This streamer was assumed to be rooted on the visible disk at 55 to 60° from the plane-of-the-sky as based on K-coronameter and XUV data. An uncertainty of as much as a factor of three still remains for the value of the axis density owing to uncertainty in the line-of-sight dimension of the streamer.  相似文献   
556.
The Coma region on a glass copy of the Palomar Sky Survey has been scanned by the PDS microdensitometer at the Napoli Observatory. A method is described for obtaining the photometric parameters and positions of the images: 12 316 objects have been found. The repositioning of the scanner over the computed coordinates is satisfatory. AGK3 stars were considered to evaluate the plate constants and the precision. Comparison with Dressel and Condon's positions of galaxies gives a r.m.s. scatter consistent with the internal error of the published list.  相似文献   
557.
We report on simultaneous optical and infrared observations of the Halley Family comet 8P/Tuttle performed with the ESO Very Large Telescope. Such multi-wavelength and coordinated observations are a good example of what can be done to support space missions. From high resolution optical spectroscopy of the CN (0,0) 388 nm and NH2 (0,9,0) 610 nm bands using UVES at UT2 we determined 12C/13C = 90 ± 10 and 14N/15N = 150 ± 20 in CN and we derived a nuclear spin temperature of NH3 of 29 ± 1 K. These values are similar to those found in Oort-Cloud and Jupiter Family comets. From low resolution long slit spectroscopy with FORS1 at UT2 we determined the CN, C3 and C2 production rates and the parent and daughter scale lengths up to 5.2 105 km tailward. From high resolution IR spectroscopy with CRIRES at UT1 we measured simultaneously the production rates and mixing ratios of H2O, HCN, C2H2, CH4, C2H6, and CH3OH.  相似文献   
558.
Calibration of a chalcogenide glass membrane, Fe(III)ISE [Fe2.5(Ge28Sb12Se60)97.5], in buffered saline media has been undertaken in order to assess the suitability of this ISE for seawater analyses. The electrode slopes in saline citrate and salicylate buffers were 26.3 and 28.2 mV/decade, respectively, for Fe3+ concentrations ranging from 10−10 M to less than 10−25 M Fe3+. The calibration lines in the citrate and salicylate buffers were essentially collinear with the response in unbuffered chloride-free standards containing >10−5 M Fe3+, demonstrating that the response of the FeISE is unaffected by chloride ions. A mechanism involving a combination of charge transfer and ion-exchange of Fe(III), at the electrode diffusion layer, can be used to explain the ≈30 mV/decade slope of the FeISE. The response of the FeISE in UV photooxidised seawater containing 8 nM total Fe was measured as the pH was changed from 8.27 to 3.51. The slope of the response was 24.2 mV/decade [Fe3+] calculated as a function of pH using Fe(III) hydrolysis constants for seawater. Moreover, the response was essentially collinear with that in citrate buffers and in unbuffered solutions containing >10−5 M Fe3+ and the slope for the combined data was 26.2 mV/decade. This study was restricted to organic-free seawater because the certainty in Fe(III)–ligand stability constants is insufficient to warrant the selection of an ideal calibration buffer system, and there is evidence that powerful chelating ligands (e.g., EDTA along with humic and fulvic acids) may alter the response of the Fe(III)ISE. The Fe dissolution rate of the FeISE in UV photooxidised seawater was found to be 1.6×10−2 nmol Fe/min, as measured by cathodic stripping voltammetry (CSV). This would contaminate a 100-ml sample by 0.8–1.6 nM Fe over a typical measurement period of 5–10 min obtained using a stability criterion of 0.5 mV/min. Various methods are proposed for reducing the level of contamination in open ocean samples that contain sub-nanomolar concentrations of iron. The FeISE has the potential to detect free Fe3+ at concentrations typically found in natural seawater.  相似文献   
559.
New Zealand has a large exclusive economic zone (EEZ) that contains a variety of marine habitats and commercially-important species. The commercial fishing industry operating within New Zealand's EEZ is of significant value to the economy and fisheries resources are managed through the extensive use of Individual Transferable Quotas (ITQs). One of the benefits of ITQs has been to better align some of the private incentives of quota owners with the public interest. These incentives contributed to an initiative proposed by the fishing industry to close large areas of New Zealand's EEZ to protect the seabed from trawling. These closed areas are termed benthic protection areas (BPAs) and protect the benthic biodiversity of about 1.1 million square kilometres of seabed—approximately 30% of New Zealand's EEZ. A significant proportion of New Zealand's known seamounts and active hydrothermal vents are protected by these closed areas. We describe and discuss the criteria used to select BPAs and some of the criticism of this marine protection initiative. We argue that the assignment of strong property rights in fishing resources was an important precondition to an industry initiative that has a significant public benefit. Where private and public interests are well aligned, government can adopt an enabling and facilitation role, ceding direct control of processes in order to get the results the align with the public interest.  相似文献   
560.
This study describes an automatic berthing system with mooring lines. It is designed to be berthed by using mooring device on the upper deck of a ship. It is to berth once maintaining parallel with the quay by controlling both forward and aft breast lines. Berthing method is used through length adjustment of mooring lines connected between ship and quay by controlling the angular velocity and the torque of hydraulic motor in mooring device. The study is conducted under three changing conditions of draft, such as even-keel, rise of the gravity center and trim to stern. Variables affecting berthing stability are determined based on the control performance of each condition. Bond graphs method is used to model the system. Controller is designed as PID control method of reference-model algorithm. The control program is composed of synchronous control system based on the equations derived with the numerical analysis. The tank test is conducted to verify the usefulness of the control program.  相似文献   
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