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101.
This study was conducted to determine the tourism potential of Alt?ndere Valley National Park with respect to its conservation and utilization. With its natural values, Alt?ndere Valley National Park is one of the internationally prominent areas of potential for the recreational and touristic facilities it offers.

A mathematical method – criterion referenced method – was applied within this study, which was done to portray the touristic potential (resulting from the touristic and recreational utilization of the national park area and recreational zone) of the national park, which was visited by an average of 200,000 local and foreign guests.

According to this method, the conservation and utilization values that appear on two opposite axes were examined in accordance with the natural resource values of the area, and conservation and utilization values for each criterion were determined. Depending on the data, the general exploitable touristic potential of the area was specified.

A survey study was conducted on groups from various disciplines and local & foreign tourists visiting the area in specifying the touristic potential of the National Park. Eleven criteria were defined concerning the area and a criterion reference was prepared for each criterion. Then, conservation and utilization values for each criterion and exploitable touristic potential were mathematically indicated. The fact that the attained values were reduced to a percentage basis provides the opportunity to compare the researched area to similar fields that use the same method. Within the scope of the method, several suggestions were made using the information obtained in the evaluation of the data for every other source value.  相似文献   
102.
Little work dealing with the evaluation of aquaculture system sustainability has so far been undertaken on a global and comparative basis. Moreover, such work is mostly based on very unbalanced approaches in terms of the dimensions of sustainable development that are taken into account. The approach adopted in this article is designed to encompass all the dimensions of sustainability including the institutional one (governance). The taking into account of this latter, in particular, together with the role played by aquaculture in sustainability at the territorial level gives the approach its original and innovative nature. The process of establishing the checklist of sustainability indicators in aquaculture relies on a hierarchical nesting approach which makes it possible to link indicators with general sustainability criteria and principles. At once multidisciplinary and participatory, the approach compares several countries with highly differentiated types of aquaculture system. An original finding from this work is that the technically most intensive farming model scores better than more extensive systems, which might have been thought to be closer to natural systems in their environmental dimension and therefore intuitively more ‘sustainable’. This result suggests relating sustainability outcomes to the level of control and of devolved responsibilities.  相似文献   
103.
Objective: The objective of our study was to determine the prevalence of alcohol and drug intoxication among fatally injured motorcyclists in a wide urban area of Zagreb, Croatia.

Methods: We conducted a single-center observational retrospective study over a 10-year period (2007–2016) in 3 counties covering an area including 1.2 million residents. We reviewed the records on fatally injured motorcyclists, collecting information relating to sex, age, cause of death, time of death in relation to the time of the crash, and the circumstances of the crash (time of day, day of the week, season). Blood alcohol concentration (BAC) and toxicology analysis results were collected and analyzed.

Results: We identified 163 deaths (95.7% males, 4.3% females). Overall, 64.2% of the victims were 20 to 39 years old. The majority (50.9%) of those fatally injured were responsible for causing the traffic crash; the rest were determined not to be responsible or the responsibility could not be determined. The most frequent causes of death were multiple injuries (55.8%) and isolated head trauma (23.3%). The rider’s BAC was above the legal limit for driving (>0.50?g/kg) in 53.8% of cases, with a mean BAC of 1.91?g/kg. There was no difference in riding a motorcycle with a BAC above the legal limit between groups defined as younger (≤39 years of age) and older (≥40 years of age). The number of people with an illegal BAC was significantly higher during weekends than during the work week. The BAC of riders who were responsible for the crash was significantly higher than that of those who were not responsible or whose responsibility could not be determined. Use of illegal drugs or nontherapeutic use of legal drugs was not common and was detected in 10.4% of fatally injured riders.

Conclusions: Alcohol intoxication has a major role in motorcycle crash–related mortality. A significant difference in BAC between fatally injured riders responsible for the accident and those who were not responsible implies that measures directed toward prevention of drinking and driving behavior could lower the number of fatal motorcycle crashes. Weekend measures, especially during spring and summer, could have particularly significant effects.  相似文献   
104.
The increased popularity of bridge employment has raised questions about its consequences for well‐being in late adult life. This research explored the consequences of bridge employment for the level of life satisfaction of older adults during the retirement transition period. Changes in life satisfaction were considered to be a function of the different intentions and motives for taking bridge jobs. Furthermore, the impact of bridge employment was empirically examined conditional on the voluntariness of the exit from the career job. Panel data on Dutch retirees (N = 1248) were investigated using conditional change models. The results demonstrate that older adults willing to prolong their work careers but unable to find bridge jobs reported lower levels of life satisfaction compared with full retirees not considering bridge employment. In addition, participation in bridge employment for financial motives was associated with decreases in life satisfaction compared with postretirement working based on intrinsic motives. Moreover, compared with voluntary retirement, involuntary retirement was detrimental to life satisfaction, but participation in a bridge job was found to mitigate this negative shock. These findings contribute to the understanding of the consequences of various postretirement employment trajectories for older individuals. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
105.
Sandbars are critical to the cross-shore movement of sediment. Prediction of cross-shore sandbar volumes requires knowledge about the functional relationship of sediment transport rate conditions with waves, currents, base slope, sediment property and water depth. In this study, experiments on cross- shore sediment transport were carried out in a laboratory wave channel for initial base slopes of 1/8, 1/10 and 1/15. Using regular waves with different deep-water wave steepness generated by a pedal-type wave generator, bar volumes caused by cross-shore sediment transport are investigated for beach materials with the medium diameter of d50?=?0.25, 0.32, 0.45, 0.62 and 0.80 mm. A non-dimensional equation for sandbar volume was obtained by using linear and non-linear regression methods through the experimental data and was compared with previously developed equations in the literature. The results have shown that the experimental data fitted well to the proposed equation with respect to the previously developed equations.  相似文献   
106.
Environmental Geochemistry and Health - One of the main sources of potential chronic exposure to potentially toxic elements is household dust, especially in an environment with known point sources...  相似文献   
107.
A 3D hydrodynamic model has been applied to the Curonian Lagoon to study the pollution impact of E. coli on a new beach that might be opened in the lagoon. Through a field survey the E. coli inputs were measured and then used in the numerical model, and through laboratory experiments the decay rate of E. coli was established. The model has been calibrated and validated for the year 2015, and several scenarios have been studied, such as sewage system breakdown, severe weather conditions or high river loads. The model has then been run for a period of 12 years to obtain a robust statistics for the pollution on the planned beach. Results show that the decay rate of E. coli is between 0.55 days and 2.3 days and the modeled decay times are compatible with these numbers. The only scenario that would create a risk for the bathing waters of the beach is a breakdown of the sewage system on the Curonian Spit. In this case the hours (and days) over legally allowable bathing threshold were computed in order to estimate the number of days the beach could be closed. These results have been confirmed by the 12 year simulations. With an influence map analysis the two most critical sewage systems could be identified.  相似文献   
108.
Psychiatric pharmaceuticals, such as anxiolytics, sedatives, hypnotics and antidepressors, are among the most prescribed active substances in the world. The occurrence of these compounds in the environment, as well as the adverse effects they can have on non-target organisms, justifies the growing concern about these emerging environmental pollutants. This study aims to analyse the effects of six psychotropic drugs, valproate, cyamemazine, citalopram, sertraline, fluoxetine and oxazepam, on the survival and locomotion of Japanese medaka Oryzias latipes larvae. Newly hatched Japanese medaka were exposed to individual compounds for 72 h, at concentrations ranging from 10 μg L?1 to 10 mg L?1. Lethal concentrations 50 % (LC50) were estimated at 840, 841 and 9,136 μg L?1 for fluoxetine, sertraline and citalopram, respectively, while other compounds did not induce any significant increase in mortality. Analysis of the swimming behaviour of larvae, including total distance moved, mobility and location, provided an estimated lowest observed effect concentration (LOEC) of 10 μg L?1 for citalopram and oxazepam, 12.2 μg L?1 for cyamemazine, 100 μg L?1 for fluoxetine, 1,000 μg L?1 for sertraline and >10,000 μg L?1 for valproate. Realistic environmental mixture of the six psychotropic compounds induced disruption of larval locomotor behaviour at concentrations about 10- to 100-fold greater than environmental concentrations.  相似文献   
109.
This paper investigates flows around a free surface piercing cylinder with Froude number F > 0.5 and Reynolds number around Re = 50,000. The aim of this work is to gain a better understanding of the flow behaviour in environmental systems such as fishways. The advances are based upon experimental and numerical results. Several flow discharges and slopes are tested to obtain both subcritical and supercritical flows. The drag force exerted on the cylinder is measured with the help of a torque gauge while the velocity field is obtained using particle velocimetry. For the numerical part, two URANS turbulence models are tested, the k-\(\omega\) SST and the RNG k-\(\varepsilon\) models using the OpenFOAM software suite for subcritical cases, and then compared with the corresponding experimental results. With fishways applications in mind, the changes in drag coefficient \(C_d\) versus Froude number and water depth are studied and experimental correlations proposed. We conclude that the most suitable URANS turbulence model for reproducing this kind of flow is the k-\(\omega\) SST model.  相似文献   
110.
Although particulate emissions from residential wood burning have become a subject of great scientific concern for a few years, data related to their impact on the air quality of large European urban centres are still missing. In the present study, we investigated the chemical and optical properties of fine (PM2.5) carbonaceous aerosols in Paris during the 2005 winter season in order to track the presence of wood burning emissions in such a large city. The use of a seven wavelength Aethalometer allowed us to document shortwave light absorption by brown-carbon-containing organic aerosols of biomass burning origin. In particular, a well-marked diurnal pattern of the spectral dependence of light absorption, with maxima during the night, could be observed every day of the campaign and attributed to wood burning emissions. Relatively high absorption Ångstrom exponents and WSOC/OC ratios (respectively 1.25 and 0.35 on average for the period of study) also indicated the importance of biomass burning aerosols in the Paris atmosphere in winter. Finally, a rough estimate of the contribution of wood burning carbonaceous aerosols to PM2.5 could be achieved. This contribution was found to be as high as 20 ± 10% on average at the Paris background site investigated here.  相似文献   
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