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121.

Background

It is widely believed that contact with the natural environment can improve physical and mental health. Urban green spaces may provide city residents with these benefits; however, there is a lack of empirical field research on the health benefits of urban parks.

Methods

This field experiment was performed in May. Seventeen males aged 21.2 ± 1.7 years (mean ± standard deviation) were instructed to walk predetermined 15-minute courses in an urban park and a nearby city area (control). Heart rate and heart rate variability (HRV) were measured to assess physiological responses. The semantic differential (SD) method, Profile of Mood States (POMS), and State-Trait Anxiety Inventory (STAI) were used to measure psychological responses.

Results

Heart rate was significantly lower while walking in the urban park than while walking in the city street. Furthermore, the urban park walk led to higher parasympathetic nervous activity and lower sympathetic nervous activity compared with the walk through the city street. Subjective evaluations were generally in accordance with physiological reactions, and significantly higher scores were observed for the ‘comfortable’, ‘natural’, and ‘relaxed’ parameters following the urban park walk. After the urban park walk, the score for the ‘vigor’ subscale of the POMS was significantly higher, whereas that for negative feelings such as ‘tension-anxiety’ and ‘fatigue’ was significantly lower. The score for the anxiety dimension of the STAI was also significantly lower after the urban park walk.

Conclusions

Physiological and psychological results from this field experiment provide evidence for the physiological and psychological benefits of urban green spaces. A brief spring-time walk in an urban park shifted sympathetic/parasympathetic balance and improved mood state.  相似文献   
122.
In this study, the urban bryophyte flora of the city of Cologne (W. Germany) was studied. A total of 143 bryophyte taxa (17 hepatics and 126 mosses) were recorded within the metropolitan area of Cologne. Three species were newly recorded for North Rhine‐Westphalia: Hannediella heimii, Schistidium helveticum and Tortula schimperi. Thirteen species red‐listed in NRW were recorded, among them hardly endangered: Bryum intermedium and Syntrichia laevipila and extinction endangered: Syntrichia papillosa. The temperate biogeographic element prevails among Cologne bryophytes. According to frequency of recordance, only 11 species are widespread over the urban area of which three are hepatics.  相似文献   
123.
We examined the utility of nutrient criteria derived solely from total phosphorus (TP) concentrations in streams (regression models and percentile distributions) and evaluated their ecological relevance to diatom and algal biomass responses. We used a variety of statistics to characterize ecological responses and to develop concentration-based nutrient criteria (derived from ecological effects) for streams in Connecticut, USA, where urbanization is the primary cause of watershed alteration. Mean background TP concentration in the absence of anthropogenic land cover was predicted to be 0.017 mg/l, which was similar to the 25th percentile of all study sites. Increased TP concentrations were significantly correlated with altered diatom community structure, decreased percent low P diatoms and diatoms sensitive to impervious cover, and increased percent high P diatoms, diatoms that increase with greater impervious cover, and chlorophyll a (P < 0.01). Variance partitioning models showed that shared effects of anthropogenic land cover and chemistry (i.e., chemistry affected by land cover) represented the majority of explained variation in diatom metrics and chlorophyll a. Bootstrapped regression trees, threshold indicator taxa analysis, and boosted regression trees identified TP concentrations at which strong responses of diatom metrics and communities occurred, but these values varied among analyses. When considering ecological responses, scientifically defensible and ecologically relevant TP criteria were identified at (1) 0.020 mg/l for designating highest quality streams and restoration targets, above which sensitive taxa steeply declined, tolerant taxa increased, and community structure changed, (2) 0.040 mg/l, at which community level change points began to occur and sensitive diatoms were greatly reduced, (3) 0.065 mg/l, above which most sensitive diatoms were lost and tolerant diatoms steeply increased to their maxima, and (4) 0.082 mg/l, which appeared to be a saturated threshold, beyond which substantially altered community structure was sustained. These criteria can inform anti-degradation policies for high quality streams, discharge permit decisions, and future strategies for watershed development and managment. Our results indicated that management practices and decisions at the watershed scale will likely be important for improving degraded streams and conserving high quality streams. Results also emphasized the importance of incorporating ecological responses and considering the body of evidence from multiple conceptual approaches and statistical analyses for developing nutrient criteria, because solely relying on one approach could lead to misdirected decisions and resources.  相似文献   
124.
Black, Latinx, and Indigenous people have contracted the SARS-CoV-2 virus and died of COVID-19 at higher rates than White people. Individuals rated public transit, taxis, and ride-hailing as the modes of transportation putting them at greatest risk of COVID-19 infection. Cycling may thus be an attractive alternative for commuting. Amid the increase in bikeshare usage during the early months of the pandemic, bikeshare companies made changes to membership requirements to increase accessibility, targeting especially essential workers. Essential workers in the United States are disproportionately Black and Latinx, underpaid, and reliant on public transit to commute to work. We document changes made by bikeshare companies, including benefits to various groups of essential workers, and we discuss such changes in the context of longstanding racial disparities in bikeshare access. While well intended, the arbitrary delineation in eligibility for such benefits by class of essential workers unwittingly curtailed access for many who may have benefited most. Given that equity in bikeshare is an important tool to improve access to safe transportation, critical changes in the distribution, accessibility, and usability of bikeshare networks is essential. Bikeshare companies, city planners, and policy makers should collaborate with community-based bike advocates to implement changes, as vocalized by those most in need of alternative forms of transportation.  相似文献   
125.
目的:通过调查郴州市城区和乡村高血压患者用药现状,筛查出药物抵抗型高血压患者,以提高药物抵抗型高血压患者的治疗率和控制率,为高血压患者个体化降压治疗方案和健康教育方案的制定提供依据。方法:随机选择郴州市区及乡村地区各200名高血压患者,以问卷的形式进行调查。结果:郴州市区药物抵抗型高血压在高血压患者中所占比例及知晓比例分别为6%、9.5%,乡村地区所占比例及知晓比例分别为7%、4%。结论:郴州市药物抵抗型高血压在高血压患者中所占比例为6.5%,农村药物抵抗型高血压患者知晓比例较低;药物抵抗型高血压患者个体化降压治疗方案有待于改进。  相似文献   
126.

Background

Interaction with nature has a relaxing effect on humans. Increasing attention has been focused on the therapeutic effects of urban green space; however, there is a lack of evidence-based field research. This study provided scientific evidence supporting the physiological and psychological effects of walking on young males in urban parks in winter.

Findings

Subjects (13 males aged 22.5 ± 3.1 years) were instructed to walk predetermined 15-minute courses in an urban park (test) and in the city area (control). Heart rate and heart rate variability (HRV) were measured to assess physiological responses. The semantic differential (SD) method, Profile of Mood States (POMS), and State-Trait Anxiety Inventory (STAI) were used to determine psychological responses.Heart rate was significantly lower and the natural logarithm of the high frequency component of HRV was significantly higher when walking through the urban park than through the city area. The results of three questionnaires indicated that walking in the urban park improved mood and decreased negative feelings and anxiety.

Conclusions

Physiological and psychological data from this field experiment provide important scientific evidence regarding the health benefits of walking in an urban park. The results support the premise that walking in an urban park has relaxing effects even in winter.  相似文献   
127.
Parthenium hysterophorus (Asteraceae) is a noxious plant that is considered one of the most invasive species in the world. We studied changes in the composition of plant species and soil properties related to the invasion of P. hysterophorus in three grassland communities of central Nepal. We collected vegetation and soil data along transects that were established in densely invaded to non-invaded areas within homogenous grassland stands. We found significant differences between invaded, transitional and non-invaded plots in species composition and soil properties. There were fewer species in non-invaded than transitional and invaded plots. By P. hysterophorus invasion both native and non-native species were supported or replaced, respectively. The concentrations of soil nitrogen and organic matter were significantly higher in transitional and invaded plots than in non-invaded plots. Soil pH, phosphorus and potassium were highest in the invaded plots, lowest in the non-invaded and intermediate in the transitional plots. Due to changes in above-ground vegetation and below-ground soil nutrient contents, P. hysterophorus invasion is likely to have an overall negative effect on the functioning of the entire ecosystem. Therefore, management of noxious P. hysterophorus is necessary to prevent future problems.  相似文献   
128.
Urban streams often contain elevated concentrations of nitrogen (N) which can be amplified in systems receiving effluent from wastewater treatment plants (WWTP). In this study, we evaluated the importance of denitrification in a stream draining urban Greensboro, NC, USA, using two approaches: (1) natural abundance of 15N–NO3 in conjunction with background NO3–N concentrations along a 7 km transect downstream of a WWTP; and (2) C2H2 block experiments at three sites and at three habitat types within each site. Overall lack of a longitudinal pattern of δ15N–NO3 and NO3–N, combined with high concentrations of NO3–N suggested that other factors were controlling NO3–N flux in the study transect. However, denitrification did appear to be significant along one portion of the transect. C2H2 block experiments showed that denitrification rates were much higher downstream of the WWTP compared to upstream, and showed that denitrification rates were highest in erosional and depositional areas downstream of the WWTP and in erosional areas upstream of the plant. Thus, the combination of the two methods for evaluating denitrification provided more insight into the spatial dynamics of denitrification activity than either approach alone. Denitrification appeared to be a significant sink for NO3–N upstream of the WWTP, but not downstream. Approximately 46% of the total NO3–N load was removed via denitrification in the upstream, urban section of the stream, while only 2.3% of NO3–N was lost downstream of the plant. This result suggests that controlling NO3–N loading from the plant could result in considerable improvement of downstream water quality.  相似文献   
129.
随着区域经济一体化进程加快,人类活动对区域可持续发展的影响越来越重要。本研究利用MODIS遥感数据,基于净初级生产力的生态足迹法(EF-NPP),对珠三角城市群6大生物生产性土地面积的均衡因子和产量因子进行计算,分析研究区2000—2020年的人均生态足迹、生态承载力、自然资源利用效率和生态适度人口的变化。结果表明: 2000—2020年,珠三角城市群人均生态足迹不断上升,化石能源用地的生态占用最高,人均生态足迹呈现出西部高、中部低、东北部较高的空间变化特征;人均生态承载力高值集中分布在肇庆市、江门市,低值集中分布在深圳市、东莞市、佛山市、中山市;生态适度人口与区域实际人口的差距随时间呈增大趋势,其中,2020年生态适度人口与区域实际人口的差距达3062万人,区域实际人口数远大于生态适度人口数,人口压力大;三大产业自然资源利用效率高,人均生态足迹所能创造的经济效益在研究期间增加3.68 万元·hm-2,年均增速为0.18万元·hm-2,且第三产业的增加速度最快。研究结果能为中小尺度区域自然资源利用效率的研究提供一定的借鉴与参考。  相似文献   
130.
A total of 26 Gram-negative, motile, gently curved, and rod-shaped isolates were recovered, during a study to determine the faeco-prevalence of Helicobacter spp. in urban wild birds. Pairwise comparisons of the 16S rRNA gene sequences indicated that these isolates belonged to the genus Helicobacter and phylogenetic analysis based on the 16S rRNA gene sequences showed that the isolates were separated into two divergent groups. The first group consisted of 20 urease-positive isolates sharing the highest 16S rRNA gene sequence identity levels of 98.5–98.6% to H. mustelae ATCC 43772T, while the second group contained six urease-negative isolates with the sequence identity level of 98.5% to the type strain of H. pametensis ATCC 51478T. Five isolates were chosen and subjected to comparative whole-genome analysis. The phylogenetic analysis of the 16S rRNA, gyrA and atpA gene sequences showed that Helicobacter isolates formed two separate phylogenetic clades, differentiating the isolates from the other Helicobacter species. Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses between strains faydin-H8T, faydin-H23T and their close neighbors H. anseris MIT 04-9362T and H. pametensis ATCC 51478T, respectively, confirmed that both strains represent novel species in the genus Helicobacter. The DNA G+C contents of the strains faydin-H8T and faydin-H23T are 32.0% and 37.6%, respectively. The results obtained for the characterization of the wild bird isolates indicate that they represent two novel species, for which the names Helicobacter anatolicus sp. nov., and Helicobacter kayseriensis sp. nov., are proposed, with faydin-H8T(=LMG 32237T = DSM 112312T) and faydin-H23T(=LMG 32236T = CECT 30508T) as respective type strains.  相似文献   
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