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1.
As urbanization increases, the identification of nest predators becomes important for avian conservation and management of urban wildlife communities. We investigated bird nest predation using artificial nests in urban areas of the KwaZulu-Natal (KZN) Province of South Africa. From June 2013 through February 2014 we installed seventy-five artificial nests in 25 suburban gardens in the Ethekwini and Msunduzi municipalities of KZN. Euplectes spp. nests were used and baited with two quail-sized, hand-made, silicon eggs. These were placed in residential gardens and monitored by camera traps for 2-weeks in winter, spring and summer respectively. Generally bird nesting occurs throughout the year in KZN’s subtropical climate, with some avoidance during the autumn season. Therefore, experiments were not conducted during autumn, as fresh nests were not available for use. Overall the rate of predation on artificial nests was 25 % (n = 19), with vervet monkeys Ceropithecus aethiops pygerythrus predating 20 % (n = 17) of the nests while domestic cats Felis catus predated 3 % (n = 2) of nests. Nest predation was significantly higher in the winter season, with 79 % of depredations occurring in winter (n = 15), 16 % in spring (n = 3) and 5 % in summer (n = 1), and in areas with less canopy cover. Our results suggest that vervet monkeys may have a negative impact on nesting birds in urban environments, however, in order to assess the rate of predation experiments on natural nests coupled with information on fledgling success is deemed necessary to investigate avian population declines.  相似文献   

2.
Urbanization brings dramatic and sudden changes to ecological conditions affecting natural communities. Cavity-nesting birds, both primary and secondary (hereafter PCN and SCN, respectively), may be limited in this novel environment because of reduced abundance of nesting sites (e.g. snags and cavities) and competition for cavities with non-native species. But humans can also directly and indirectly provide nest sites (e.g., nest boxes, crevices on houses), especially for SCN species, potentially partially compensating for negative effects. We investigated whether and how PCNs and humans facilitated the cavity-nesting bird community along a gradient of urbanization. To do so, we estimated the abundance of cavity-nesting species between 1998 and 2010 at 135, 1-km2 sites that differed in the degree of urbanization (0–100 % forest cover). Also, we found 367 nests on a subset of 31 sites. PCNs (n = 67 nests) nested mostly on snags (98.5 %), while native SCNs (n = 141) used both natural (71.63 %) and anthropogenic (28.37 %) cavities. Non-native SCNs (n = 159 nests) used mostly anthropogenic cavities (98.11 %). PCN abundance facilitated native SCN abundance on sites with more than 12 % forest cover at 1-km2 scale, but not at less forested sites. There, native SCNs nested primarily (59 %) in anthropogenic cavities. Human facilitation allowed native SCNs to successfully use and reproduce where snags were scarce, changing the composition and structure of the cavity-nesting bird community within the most urbanized sites. Flexible nest site selection and human facilitation provide new opportunities for native cavity-nesting birds in a rapidly changing world.  相似文献   

3.
Understanding the factors determining the occupancy and detection probability of birds in human dominated environments is important for their conservation. In this study we investigated various environmental variables believed to influence the site occupancy and detection probability of Trumpeter Hornbill (Bycanistes bucinator) in urban-forest mosaics of KwaZulu-Natal, South Africa. Presence/absence data were collected from a total of 50 point count stations established between September 2014 and March 2015 in urban-forest mosaics of Durban, Eshowe and Mtunzini. Mean occupancy rate of Trumpeter Hornbill was 0.40 ± 0.09 with a low detection probability of 0.28 ± 0.04. For Trumpeter Hornbills, large trees influenced their occupancy positively (sum AIC weight (ω i ) = 79%) while relative human abundance negatively influenced their occupancy (ω i = 91%). Model selection suggested that housing density had a strong negative influence on detection probability of Trumpeter Hornbills (ω i ?=?82?%?) and availability of fruiting trees influenced their detection positively (ω i ?=?29%). With continued changing land use in KwaZulu-Natal, these finding are important for conservation of Trumpeter Hornbills as we provide insight into landscape variables or features that influence Trumpeter Hornbill’s occupancy and detection in areas of urban-forest mosaics.  相似文献   

4.

Background

Physical exercise (PE), virtual reality-based exercise (VRE), and brain exercise (BE) can influence physical and cognitive conditions in older persons. However, it is not known which of the three types of exercises provide the best effects on physical and cognitive status, and which exercise is preferred by older persons. This study compared the effects of PE, VRE, and BE on balance, muscle strength, cognition, and fall concern. In addition, exercise effort perception and contentment in older persons was evaluated.

Methods

Eighty-four older persons (n?=?84) were randomly selected for PE, VRE, BE, and control groups. The exercise groups received 8-week training, whereas the control group did not. Balance was assessed by Berg Balance Scale (BBS) and Timed Up and Go test (TUG), muscle strength by 5 Times Sit to Stand (5TSTS) and left and right hand grip strength (HGS), cognition by Montreal Cognitive Assessment (MoCA) and Timed Up and Go test Cognition (TUG-cog), fall concern by Fall Efficacy Scale International (FES-I), exercise effort perception by Borg category ratio scale (Borg CR-10), and exercise contentment by a questionnaire.

Results

After exercise, PE significantly enhanced TUG and 5TSTS to a greater extent than VRE (TUG; p?=?0.004, 5TSTS; p?=?0.027) and BE (TUG; p?=?0,012, 5TSTS; p?<?0.001). VRE significantly improved MoCA (p?<?0.001) and FES-I (p?=?0.036) compared to PE, and 5TSTS (p?<?0.001) and FES-I (p?=?0.011) were improved relative to BE. MoCA was significantly enhanced by BE compared to PE (p?<?0.001) and both MoCA and TUG-cog were improved compared to VRE (p?=?0.04). PE and VRE significantly (p < 0.001) increased Borg CR-10 in all exercise sessions, whereas BE showed a significant improvement (p?< 0.001) in the first 4 sessions. Participants had a significantly greater satisfaction with BE than controls (p?=?0.006), and enjoyed VRE and BE more than PE (p?< 0.001). Subjects in all exercise groups exhibited benefits compared to the control group (p?< 0.001).

Conclusions

PE provided the best results in physical tests, VRE produced measurable improvements in physical and cognition scores, while BE enhanced cognition ability in older persons. Older persons preferred VRE and BE compared to PE. Both exercises are suggested to older persons to improve physical and cognitive conditions.
  相似文献   

5.
This study quantified the impact of high stream flows on reproductive activities of river chub (Nocomis micropogon). Using observed relationships between flow and reproductive activities, the number of predicted damaging flow events was compared between streams with extant river chub populations and urbanized streams. Monitoring the survivorship of river chub nests during 2013–2014 (N = 101) revealed consistent relationships between interval peak flow measured at flow gauges and the integrity of river chub nests within sites. Flow-mediated disruption of nests was frequent, and interval peak flows were significantly correlated with nest erosion rates. Logistic regression between fate of river chub nests and standardized peak flow (Qs) during monitoring intervals identified thresholds of peak flow corresponding to complete and partial destruction of river chub nests. Observed thresholds were used to predict the frequency of potentially damaging flows in urbanized versus river chub study streams, based on archival flow monitoring data. Repeated measures analysis revealed that the frequency of flows predicted to result in the loss of all nests was significantly higher in urbanized streams (F = 122.2; df = 1; P < 0.001 ). While key life history information needs to be determined to fully understand the impacts of high flows on river chub population dynamics, results indicate the disruption of nests through frequent high flows as a mechanism for the reduction of this important species in urbanized areas. Improved understanding of the interactions between stream processes and biota will aid in the design of specific stream protection and restoration strategies.  相似文献   

6.
As urbanization in the landscape increases, some urban centers are setting aside habitat for wildlife. This habitat may be particularly valuable to declining or conservation-priority species. One group in particular need of conservation actions that may benefit from habitat located in urban areas is grassland birds. Declines of grassland bird species have been particularly severe in the Midwestern U.S., where most grassland cover has been lost, fragmented, and surrounded by unsuitable habitat. Conservation efforts have focused on protecting large grasslands surrounded by minimal amounts of trees and development. Although urban development is considered hostile to grassland birds, this assumption has received little attention. In heavily fragmented landscapes where habitat is limited, urban grasslands may be of significant value to grassland birds. We examined grassland bird response to development and additional landscape and habitat variables in the greater Chicago metropolitan area. In 2012 and 2013, we surveyed bird communities in grassland patches along a gradient of urbanization and patch sizes. Density of Savannah Sparrows (Passerculus sandwichensis) increased with amount of development, while density of Sedge Wrens (Cistothorus platensis) decreased. Development did not appreciably impact Bobolinks (Dolichonyx oryzivorus), Dickcissels (Spiza americana), Eastern Meadowlarks (Sturnella magna), Grasshopper Sparrows (Ammodramus savannarum), or Henslow’s Sparrows (Ammodramus henslowii). Patch size had a positive effect on species densities. These results indicate that for many conservation-priority grassland birds, urban landcover surrounding grasslands generally has neutral rather than negative effects on habitat use. Therefore, grasslands in developed landscapes may provide valuable contributions to regional conservation efforts.  相似文献   

7.
Urbanization has been identified as a threat to biodiversity due to landscape modifications. Studies of parasite ecology in urbanized areas lagged behind those made on macro organisms. Here we studied infection prevalence of haemosporidian parasites in an avian community of an urban forest from Germany, and its relationship with bird abundance and body mass. We used PCR to amplify a fragment of the mtDNA cyt b gene to determine the infection status of birds, and bird point counts to determine bird relative abundances. The avifauna was dominated by two small sized insectivore passerines (Parus major, Cyanistes caeruleus), representing ~40 % of the total bird records. The highest haemosporidian prevalence was recorded for Turdus philomelos (100 %) and for Fringilla coelebs (75 %). Bird abundance and body mass were positively associated with infection status for two haemosporidian genera: Plasmodium and Leucocytozoon. Infection rate was lower in juveniles compared to adult birds. We recorded a total of 7 Plasmodium, 26 Haemoproteus, and 10 Leucocytozoon lineages. Avian malaria (P. relictum) was detected infecting 5 individuals of P. major, the most abundant species in the community. These results, together with those of previous studies at the same site, suggest that potentially any of the genetic haemosporidian lineages detected in this urban forest can be transmitted across native and pet bird species, and to species of conservation concern housed at aviaries.  相似文献   

8.
At present, urban areas cover almost 3% of the Earth’s terrestrial area, and this proportion is constantly increasing. Although urbanization leads to a decline in biodiversity, at the same time it creates extensive habitats that are exploited by an assemblage of organisms, including birds. The species composition and density of birds nesting in towns and cities are determined by the types of buildings, the structure and maturity of urban greenery, and habitat diversity. In contrast, the habitat traits shaping the community of birds wintering in urban areas are not known. The aim of this work was to assess the influence of habitat structure, food resources and the urban effects (pollution, noise, artificial light) on an assemblage of birds overwintering in an urban area. It was carried out in 2014 and 2015 in the city of Kraków (southern Poland), on 56 randomly chosen sample plots, in which the composition, density and interseasonal similarity of bird assemblage were assessed with line transect method. A total of 64 bird species (mean = 17.7 ± 4.9 SD species/plot) was recorded. The mean density was 89.6 ind./km ±63.3 SD. The most numerous species were Great Tit Parus major, Magpie Pica pica, Blackbird Turdus merula, Blue Tit Cyanistes caeruleus, Rook Corvus frugilegus, Fieldfare Turdus pilaris and House Sparrow Passer domesticus. Noise adversely affected species numbers and density, but artificial light acted positively on the density of birds and their interseasonal stability. The species richness and density of birds were also determined by the number of food sources available (e.g. bird-feeders). In addition, the greater the proportion of open areas, the fewer species were recorded. In contrast, the more urban greenery there was, the greater the density of the entire bird assemblage. Urban infrastructure (buildings, roads, refuse tips) had a positive effect on the interseasonal stabilization of the species composition of wintering birds. The results of this work indicate that the urban effect, i.e. noise and light pollution, apart from purely habitat factors, provide a good explanation for the species richness, density and stability of bird assemblage wintering in urban areas.  相似文献   

9.

Background

The participation of master cross-country (XC) skiers in training and competition has increased during the last decades; however, little is known yet about whether these athletes differ from their younger counterparts in aspects of performance such as pacing. Therefore, the aim of the present study was to examine the combined effect of age and performance (race time) on pacing in cross-country (XC) skiing. We analyzed all finishers (n?=?79,722) in ‘Vasaloppet’ from 2012 to 2017, the largest cross-country skiing race in the world, classified according to their race time into 10 groups: 3-4 h, 4-5 h, ..., 12-13 h.

Results

A trivial main effect of sex on total pace range was observed (p?<?0.001, η2?=?0.002), where women (44.1?±?10.2%) had larger total pace range than men (40.9?±?11.8%). A large main effect of performance group on total pace range was shown (p?<?0.001, η2?=?0.160), where the smallest total pace range was 21.8?±?1.9% (3-4 h group) and the largest 50.1?±?9.9% (10-11 h group). A trivial sex×performance group interaction on total pace range was found (p?<?0.001, η2?=?0.001) with the largest sex difference in pacing shown in 9-10 h group. A trivial and small main effect of age was found in women (p?<?0.001, η2?=?0.005) and men (p?<?0.001, η2?=?0.011), respectively, where the masters had smaller total pace range than their younger counterparts. A trivial age group×performance group interaction on total pace range was observed in both women (p?<?0.001, η2?=?0.008) and men (p?<?0.001, η2?=?0.006) with smaller differences among age groups in the faster performance groups.

Conclusions

In summary, master XC skiers adopted a relatively even pacing independently from their race time and the differences in pacing from the younger XC skiers were more pronounced in the slower masters. These findings suggest that exercise attenuates the decline of performance in master XC skiers as shown by the similar pacing strategies between fast master XC skiers and their younger counterparts.
  相似文献   

10.
Urbanization has caused the local extinction of several butterfly species around the world, while others have managed to thrive in urban areas. Butterflies of the genus Eumaeus are among the most striking and colorful lycaenid butterflies in the Americas, but their neurotoxic hostplants, cycads, are a highly threatened plant group. The main threats for cycads are the loss and modification of their habitats and their removal for ornamental purposes, which in addition to their slow growth rate, make them highly vulnerable. Ornamental cycads are taken from natural habitats to urban areas, where they are playing an important role for Eumaeus reproduction. We here report two cases in which two Eumaeus species (E. childrenae, E. atala) are following and utilizing ornamental cycads to reproduce in urban areas, showing how significant urban areas can be, ecologically speaking. Aside from having enormous potential as flagship species for conservation in urban areas, these butterfly and plant species, and their interactions, shed encouraging light on the idea of putting reconciliation ecology ideas into action.  相似文献   

11.
Ligustrum lucidum, a tree native to China has naturalized in Japan where it is often planted in parks and along roads. Naturalized individuals in urban woodlands have uncertain competitiveness against native species, particular in light of the frequent pruning undertaken in these woodlands. We compared fitness-related traits of Ligustrum against two co-occurring native species: a pioneer tree (Mallotus japonicus) and an understory tree (Eurya japonica) under pruned and un-pruned settings. A growth experiments where we assessed the leaf and whole plant characteristics of the 3 species under two environments simulating forest edge and forest interior, and two pruning treatments (with or without) was conducted. Under simulated forest edge without pruning, Ligustrum had lower stem growth and Amax (maximum photosynthetic rate) than Mallotus, suggesting that native species can competitively suppress invasive expansion. With pruning, however, Ligustrum resprouted vigorously in both spring and summer with significantly higher apical growth and total shoots than Mallotus and Eurya in forest edge and interior, respectively. Also, with similar Amax between resprouts of Ligustrum and Mallotus, we see a reversal of competitive advantage in favor of Ligustrum in forest edge. In the forest interior, Ligustrum exhibited shade tolerant properties (i.e., Amax, chlorophyll a/b, and leaf density) similar to Eurya but had more resprout shoots, suggesting that the invader also maintains an advantage under low light. The competitiveness of Ligustrum clearly increased with human disturbance in the form of park pruning. Such management practice can inadvertently enhance the invasiveness of exotic species in urban settings.  相似文献   

12.
Scatter-hoarding by animals is an effective mechanism for seed dispersal and plant regeneration in natural ecosystems, however, studies on the interaction between hoarding animals and urban forest are insufficient. By methods of acorn placement experiment, cache and seedling survey, the relationship between acorn dispersal and seedlings distribution of Mongolian oak (Quercus mongolica) and scatter hoarding rodents was investigated at the Northeast Forestry University Woodland of Harbin, China. Results indicated that main scatter hoarding rodents of acorns were squirrels (Sciurus vulgaris) and chipmunks (Eutamias sibiricus). Mongolian oak seedlings were distributed primarily in Mongolian Scotch pine, birch and larch parcels (df = 3, χ 2 = 1502.77, P < 0.01). Most seedlings were 4 ~ 6 years (df = 3, χ 2 = 408.23, P < 0.01) and mainly dispersed within range of 100 m from the parent trees. The activity frequency and cache habitats of squirrels coincided with the distribution pattern of Mongolian oak seedlings, which meant scatter hoarding rodents had important effects on acorn dispersal and seedling establishment of urban Mongolian oaks.  相似文献   

13.
Urbanization tends to remove or isolate green areas into fragments or restrict them to narrow corridors inserted in a matrix of buildings. Nevertheless, urban green areas may act as refuges for fauna and bats are among the animals able to use such habitats. Using bioacoustics we investigated the influence of green areas on the activity of insectivorous bats in the metropolitan area of Recife, a conurbation of 4 million people in the Atlantic forest of Northeastern Brazil. Bat activity was statistically higher in green areas, based on calls (t?=?2.5298, p?=?0.0165), but not on feeding buzzes (t?=?1.8132, p?=?0.0817) or social calls (t?=??1.5551, p?=?0.1329). Several species were able to persist in an urban matrix and calls were classified into 16 sonotypes, belonging to five families (Emballonuridae, Molossidae, Noctilionidae, Phyllostomidae and Vespertilionidae). However, activity was significantly more associated with areas with vegetation, indicating that green remnants are hotspots for bat activity. Our results indicate that most insectivorous bats have a biased use of the urban landscape and the maintenance of urban green areas is essential to preserve them and the environmental services they provide.  相似文献   

14.
In urban and suburban ecosystems, biodiversity can depend on various non-native plant species, including crop plants, garden plants and weeds. Non-native plants may help to maintain biodiversity by providing a source of forage for pollinators in these ecosystems. However, the contribution of plants in urban and agricultural areas to ecosystem services has often been underestimated in biodiversity assessments. In this study, we investigated the pollen sources of native honeybees (Apis cerana) in an arboretum containing native trees and urban and agricultural plants in a suburban landscape. We surveyed the flowering tree species planted inside the arboretum, which were potential pollen sources. The number of potential pollen-source species of native trees peaked in June and July and decreased after August. We collected A. cerana pollen balls every month and identified plant species of pollen in the collected pollen balls using DNA barcoding. In total, we identified 29 plant species from A. cerana pollen balls. The probability of A. cerana using pollen from urban and agricultural plants was higher in July and August than in June. A. cerana collected pollen forages from native tree species (53%), but also gathered pollen from crop plants (13%), garden trees (19%) and native and non-native weeds (14%); the predominant pollen sources in September and October were the garden tree Ulmus parvifolia and the non-native weed Solidago altissima. We found that native honeybees used plants from a variety of habitats including non-native plants to compensate for apparent seasonal shortages of native tree sources in suburban ecosystems. Our results highlight the importance of assessments of both positive and negative roles of non-native plants in urbanized ecosystems to improve biodiversity conservation.  相似文献   

15.

Background

This study evaluated the effects of a combined innovative training regime consisting of stochastic resonance whole-body vibration (SR-WBV) and a dance video game (DVG) on physical performance and muscle strength in long-term-care dwelling elderly.

Methods

Thirthy long-term-care elderly were randomly allocated to an intervention group (IG; n?=?16) receiving combined SR-WBV training and DVG, or a sham group (SG; n?=?14). IG performed five sets one minute of SR-WBV, with one minute rest between sets (base frequency 3 Hz up to 6 Hz, Noise 4) during the first five weeks on three days per week. From week five to eight a DVG was added to SR-WBV for IG on three days per week. SG performed a five-set SR-WBV program (1 Hz, Noise 1) lasting five times one minute, with one minute rest in between, three days a week. From week five to eight stepping exercises on a trampoline were added on three days per week. Primary outcome: Short physical performance battery (SPPB). Secondary outcome: isometric maximal voluntary contraction (IMVC), and sub phases of IMVC (Fsub), isometric rate of force development (IRFD) and sub time phases of IRFD (IRFDsub) were measured at baseline, after four and eight weeks. ANOVA with repeated measures was used for analyses of time and interaction effects and MANOVA determined between group intervention effects.

Results

Between group effects revealed significant effects on the SPPB primary outcome after four weeks F(1, 27)?=?6.17; p?=?0.02) and after eight weeks F(1,27)?=?11.8; p?=?0.002). Secondary muscle function related outcome showed significant between group effects in IG on IRFD, Fsub 30 ms, 100 ms, 200 ms and IRFDsub 0-30 ms, 0-50 ms, 0-100 ms and 100-200 ms compared to SG (all p?<?0.05).

Conclusions

Eight weeks SR-WBV and DVG intervention improved lower extremity physical function and muscle strength compared to a sham intervention in long-term-care elderly. SR-WBV and DVG seems to be effective as a training regime for skilling up in long-term-care elderly.
  相似文献   

16.
Characterizing the impacts of hydrologic alterations, pollutants, and habitat degradation on macroinvertebrate species assemblages is of critical value for managers wishing to categorize stream ecosystem condition. A combination of approaches including trait-based metrics and traditional bioassessments provides greater information, particularly in anthropogenic stream ecosystems where traditional approaches can be confounded by variously interacting land use impacts. Macroinvertebrates were collected from two rural and three urban nested study sites in central Missouri, USA during the spring and fall seasons of 2011. Land use responses of conventional taxonomic and trait-based metrics were compared to streamflow indices, physical habitat metrics, and water quality indices. Results show that biotic index was significantly different (p?<?0.05) between sites with differences detected in 54 % of trait-based metrics. The most consistent response to urbanization was observed in size metrics, with significantly (p?<?0.05) fewer small bodied organisms. Increases in fine streambed sediment, decreased submerged woody rootmats, significantly higher winter Chloride concentrations, and decreased mean suspended sediment particle size in lower urban stream reaches also influenced macroinvertebrate assemblages. Riffle habitats in urban reaches contained 21 % more (p?=?0.03) multivoltine organisms, which was positively correlated to the magnitude of peak flows (r 2?=?0.91, p?=?0.012) suggesting that high flow events may serve as a disturbance in those areas. Results support the use of macroinvertebrate assemblages and multiple stressors to characterize urban stream system condition and highlight the need to better understand the complex interactions of trait-based metrics and anthropogenic aquatic ecosystem stressors.  相似文献   

17.
Exotic trees can sustain native birds in urban woodlands   总被引:2,自引:1,他引:1  
Native landscaping has been proposed as a means of increasing native bird diversity and abundance in urban landscapes. However residents’ preferences for vegetation are such that exotic plants are often preferred over natives. We investigated the extent to which native birds foraged in three common native and three exotic tree species in mixed urban woodland during four seasons. We predicted that native birds would spend more time foraging in native trees, and that food resources provided by deciduous exotic trees would be more seasonal than those provided by non-deciduous natives. Native birds spent a lot of time foraging in two of the native tree species, but very little time in native red beech (Nothofagus fusca). They used exotic oak (Quercus robur) throughout the year, and sycamore (Acer pseudoplatanus) seasonally. Oak and European beech (Fagus sylvatica) were used by the largest number of species overall, because they attracted both native and exotic birds. With the exception of tree fuchsia (Fuschia excorticata), which produces large volumes of nectar followed by fruits, all tree species were sources of invertebrates for insectivorous feeding. Seasonality of use was high only in sycamore, indicating limited support for our second prediction. We show that being native doesn’t necessarily entail being a good food source for native birds, and popular landscaping exotic species, such as oak, provide foraging opportunities across all seasons.  相似文献   

18.

Background

Rapid compensatory stepping plays an important role in preventing falls when balance is lost; however, these responses cannot be accurately quantified in the clinic. The Microsoft Kinect? system provides real-time anatomical landmark position data in three dimensions (3D), which may bridge this gap.

Methods

Compensatory stepping reactions were evoked in 8 young adults by a sudden platform horizontal motion on which the subject stood or walked on a treadmill. The movements were recorded with both a 3D-APAS motion capture and Microsoft Kinect? systems. The outcome measures consisted of compensatory step times (milliseconds) and length (centimeters). The average values of two standing and walking trials for Microsoft Kinect? and the 3D-APAS systems were compared using t-test, Pearson’s correlation, Altman-bland plots, and the average difference of root mean square error (RMSE) of joint position.

Results

The Microsoft Kinect? had high correlations for the compensatory step times (r?=?0.75–0.78, p?=?0.04) during standing and moderate correlations for walking (r?=?0.53–0.63, p?=?0.05). The step length, however had a very high correlations for both standing and walking (r?>?0.97, p?=?0.01). The RMSE showed acceptable differences during the perturbation trials with smallest relative error in anterior-posterior direction (2-3%) and the highest in the vertical direction (11–13%). No systematic bias were evident in the Bland and Altman graphs.

Conclusions

The Microsoft Kinect? system provides comparable data to a video-based 3D motion analysis system when assessing step length and less accurate but still clinically acceptable for step times during balance recovery when balance is lost and fall is initiated.
  相似文献   

19.
In order to enhance our understanding of the nature of poker-machine problem-gambling, a community sample of 37 poker-machine gamblers (M age = 32 years, M PGSI = 5; PGSI = Problem Gambling Severity Index) were assessed for urge to gamble (responses on a visual analogue scale) and altered state of consciousness (assessed by the Altered State of Awareness dimension of the Phenomenology of Consciousness Inventory) at baseline, after a neutral cue, and after a gambling cue. It was found that (a) problem-gambling severity (PGSI score) predicted increase in urge (from neutral cue to gambling cue, controlling for baseline; sr 2 = .19, p = .006) and increase in altered state of consciousness (from neutral cue to gambling cue, controlling for baseline; sr 2 = .57, p < .001), and (b) increase in altered state of consciousness (from neutral cue to gambling cue) mediated the relationship between problem-gambling severity and increase in urge (from neutral cue to gambling cue; κ2 = .40, 99 % CI [.08, .71]). These findings suggest that cue-reactive altered state of consciousness is an important component of cue-reactive urge in poker-machine problem-gamblers.  相似文献   

20.
Green roofs have been described as technical solutions to overcome urban environmental problems, such as decrease of vegetation and stormwater management. In the present study, two pilot 20 m2 extensive green roofs were implemented in an urban Mediterranean region, at a 1st storey on a warehouse building structure, in order to test the adequacy of different substrates for supporting aromatic plants (Lavandula dentata, Helichrysum italicum, Satureja montana, Thymus caespititius and Thymus pseudolanuginosus). Experimental substrates included expanded clay and granulated cork as main components, supplemented with organic matter and crushed egg shell. A commercial substrate that obeys to FLL guidelines was also tested. Plant growth was assessed and compared within each platform. All experimental substrates proved to be adequate for vegetation growth, with the combination of 70% expanded clay, 15% organic matter and 15% crushed egg shell showing the best results regarding plant establishment and growth over time. Water runoff quality parameters - turbidity, pH, conductivity, NH4 +, NO3 ?, PO4 3? - met standard values required for water reuse for non-potable purposes, such as toilet flushing or irrigation. Preliminary qualitative thermographic measurements comparing surface temperature of different plant species and the substrate showed that temperature of vegetation surface was lower than substrate, reinforcing green roofs benefits of lowering air temperature in their surroundings. The present research shows that aromatic vegetation combined with clay substrates are suitable for green roofs located in countries of the Mediterranean region.  相似文献   

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