scholarly journals Detecting the Turning Points of Grassland Autumn Phenology on the Qinghai-Tibetan Plateau: Spatial Heterogeneity and Controls

2021 ◽  
Vol 13 (23) ◽  
pp. 4797
Author(s):  
Yanzheng Yang ◽  
Ning Qi ◽  
Jun Zhao ◽  
Nan Meng ◽  
Zijian Lu ◽  
...  

Autumn phenology, commonly represented by the end of season (EOS), is considered to be the most sensitive and crucial productivity indicator of alpine and cold grassland in the Qinghai-Tibetan Plateau. Previous studies typically assumed that the rates of EOS changes remain unchanged over long time periods. However, pixel-scale analysis indicates the existence of turning points and differing EOS change rates before and after these points. The spatial heterogeneity and controls of these turning points remain unclear. In this study, the EOS turning point changes are extracted and their controls are explored by integrating long time-series remote sensing images and piecewise regression methods. The results indicate that the EOS changed over time with a delay rate of 0.08 days/year during 1982–2015. The rates of change are not consistent over different time periods, which clearly highlights the existence of turning points. The results show that temperature contributed most strongly to the EOS changes, followed by precipitation and insolation. Furthermore, the turning points of climate, human activities (e.g., grazing, economic development), and their intersections are found to jointly control the EOS turning points. This study is the first quantitative investigation into the spatial heterogeneity and controls of the EOS turning points on the Qinghai-Tibetan Plateau, and provides important insight into the growth mechanism of alpine and cold grassland.

Author(s):  
Yuqian Wang ◽  
Mingyan Jiang ◽  
Yinshu Huang ◽  
Zhiyi Sheng ◽  
Xiao Huang ◽  
...  

This study illustrated the physiological and psychological effects of watching videos of different durations showing bamboo forests with varied structures. Physiological indicators, including EEG (electroencephalogram), blood pressure, skin conductance, and pulse, were monitored in 180 Chinese university students (mean age: 20.72 ± 2.56 years) while they were watching bamboo videos. Before and after watching the videos, their psychological indicators, including positive and negative moods, were measured using the Profile of Mood States questionnaire. After watching the bamboo videos of different durations, all of the physiological indicators responded to the stimulation after only 1 min. The indicators showed different trends at 1, 3 and 5 min. EEG decreased and then was maintained at a stable level after 1 min, and the high β, low β, and α waves had no significant differences between 1, 3 and 5 min. Blood pressure dropped to a stable state after 3 min, and the decline was significantly different greater after 3 min than after 1 min. Skin conductance increased for 1 to 5 min, and it did not stabilize after a long time (5 min). Pulse decreased after 1 min but increased after 5 min. After watching the videos with bamboo of varying structures, the physiological and psychological indicators showed significantly different changes. Skin conductance significantly increased (mean value: 6.78%), and the amount of sweat was more effectively reduced, thereby reducing tension, when the students viewed videos of sympodial bamboo forests compared with monopodial bamboo forests. Bamboo forests with a higher canopy density (0.83–0.85) could significantly decrease α waves (mean value: 1.50 Hz), relaxing the human body. High β and low β waves showed greater decreases, with tension reduced more effectively, when bamboo forests with a low tilt ratio (< 1.5%) were viewed. Bamboo forests with neat undergrowth could have more beneficial physiological and psychological effects on the human body.


Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 726
Author(s):  
Fulvia Ceccarelli ◽  
Venusia Covelli ◽  
Giulio Olivieri ◽  
Francesco Natalucci ◽  
Fabrizio Conti

Background: The COVID-19 pandemic contributes to the burden of living with different diseases, including Systemic Lupus Erythematosus (SLE). We described, from a narrative point of view, the experiences and perspectives of Italian SLE adults during the COVID-19 emergency, by distinguishing the illness experience before and after the lockdown. Methods: Fifteen patients were invited to participate. Illness narratives were collected between 22 and 29 March 2020 using a written modality to capture patients’ perspectives before and after the COVID-19 lockdown. We performed a two-fold analysis of collected data by distinguishing three narrative types and a qualitative analysis of content to identify the relevant themes and sub-themes reported. Results: Eight narratives included in the final analysis (mean length 436.9 words) have been written by eight females (mean age 43.3 ± 9.9 years, mean disease duration 13.1 ± 7.4 years). Six patients provided a quest narrative, one a chaos and the remaining one a restitution narrative. By text content analysis, we identified specific themes, temporally distinct before and after the lockdown. Before COVID-19, all the patients referred to a good control of disease, however the unexpected arrival of the COVID-19 emergency broke a balance, and patients perceived the loss of health status control, with anxiety and stress. Conclusions: We provided unique insight into the experiences of people with SLE at the time of COVID-19, underlining the perspective of patients in relation to the pandemic.


Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2278
Author(s):  
Anna Micheluz ◽  
Eva Mariasole Angelin ◽  
João Almeida Lopes ◽  
Maria João Melo ◽  
Marisa Pamplona

Light is a determining factor in the discoloration of plastics, and photodegradation processes can affect the molecular structures of both the polymer and colorants. Limited studies focused on the discoloration of heritage plastics in conservation science. This work investigated the discoloration of red historical polyethylene (PE) objects colored with PR 48:2 and PR 53:1. High-density and low-density PE reference polymers, neat pigment powders, and historical samples were assessed before and after accelerated photoaging. The applied methodology provided insight into the individual light-susceptibility of polyethylenes, organic pigment lakes, and their combined effect in the photoaging of historical plastic formulations. After light exposure, both PE references and historical samples yellowed, PR53:1 faded, and PR 48:2 darkened; however, both organic pigments faded severely in the historical samples. This highlights the role played by the plastic binder likely facilitating the pigment photofading. Fourier transform infrared spectroscopy and mass spectrometry techniques—EGA-MS, PY-GC/MS, and TD-GC/MS—were successfully employed for characterizing the plastic formulations and degradation. The identification of phthalic compounds in both aged β-naphthol powders opens new venues for studies on their degradation. This work’s approach and analytical methods in studying the discoloration of historical plastics are novel, proving their efficacy, reliability, and potentiality.


2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Jiekun He ◽  
Siliang Lin ◽  
Jiatang Li ◽  
Jiehua Yu ◽  
Haisheng Jiang

AbstractThe Tibetan Plateau (TP) and surrounding regions have one of the most complex biotas on Earth. However, the evolutionary history of these regions in deep time is poorly understood. Here, we quantify the temporal changes in beta dissimilarities among zoogeographical regions during the Cenozoic using 4,966 extant terrestrial vertebrates and 1,278 extinct mammal genera. We identify ten present-day zoogeographical regions and find that they underwent a striking change over time. Specifically, the fauna on the TP was close to the Oriental realm in deep time but became more similar to the Palearctic realms more recently. The present-day zoogeographical regions generally emerged during the Miocene/Pliocene boundary (ca. 5 Ma). These results indicate that geological events such as the Indo-Asian Collision, the TP uplift, and the aridification of the Asian interior underpinned the evolutionary history of the zoogeographical regions surrounding the TP over different time periods.


2004 ◽  
Vol 1 (1) ◽  
pp. 131-142
Author(s):  
Ljupčo Todorovski ◽  
Sašo Džeroski ◽  
Peter Ljubič

Both equation discovery and regression methods aim at inducing models of numerical data. While the equation discovery methods are usually evaluated in terms of comprehensibility of the induced model, the emphasis of the regression methods evaluation is on their predictive accuracy. In this paper, we present Ciper, an efficient method for discovery of polynomial equations and empirically evaluate its predictive performance on standard regression tasks. The evaluation shows that polynomials compare favorably to linear and piecewise regression models, induced by the existing state-of-the-art regression methods, in terms of degree of fit and complexity.


2020 ◽  
pp. 105-111
Author(s):  
Giang Huynh Huong ◽  
Tan Nguyen Thi ◽  
Hung Nguyen Van

Background: Sciatica due to lumbar spondylosis is a common disease syndrome, include pathological signs from lumbar spine and sciatic nerve. It occurs for a long time and affects to working ability and daily life. Currently there are many methods of treatment with modern medicine and traditional medicine. Electroacupuncture combined with acupressure point, massage treatment and “Doc hoat tang ky sinh” remedy is a highly effective method on treating sciatica due to lumbar spondylosis. Objectives: To evaluate the effectives of electroacupuncture combined with acupressure point, massage treatment and “Doc hoat tang ky sinh” remedy on treating sciatica due to lumbar spondylosis. Materials and Method: A total of 43 patients was diagnosed sciatica caused by lumbar spondylosis who treated at Thua Thien Hue Traditional Medicine Hospital. The study was designed by method of prospective study, assessed the results before and after the treatment. Results: Very good: 34.9%; good: 34.9%; average 7%. There was not any unexpected effects observed in this trial. Conclusion: Electroacupuncture combined with acupressure point, massage treatment and “Doc hoat tang ky sinh” remedy is a effective method on treating sciatica caused by lumbar spondylosis. Key words: sciatica, lumbar spondylosis, acupuncture, electroacupuncture, acupressure point, massage treatment


Author(s):  
Bing Song ◽  
Xiao-Yong Yan ◽  
Suoyi Tan ◽  
Bin Sai ◽  
Shengjie Lai ◽  
...  

Understanding the spatial interactions of human mobility is crucial for urban planning, traffic engineering, as well as for the prevention and control of infectious diseases. Although many models have been developed to model human mobility, it is not clear whether such models could also capture the traveling mechanisms across different time periods (e.g. workdays, weekends or holidays). With one-year long nationwide location-based service (LBS) data in China, we investigate the spatiotemporal characteristics of population movements during different time periods, and make thorough comparisons for the applicability of five state-of-the-art human mobility models. We find that population flows show significant periodicity and strong inequality across temporal and spatial distribution. A strong “backflow” effect is found for cross-city movements before and after holidays. Parameter fitting of gravity models reveals that travels in different type of days consider the attractiveness of destinations and cost of distance differently. Surprisingly, the comparison indicates that the parameter-free opportunity priority selection (OPS) model outperforms other models and is the best to characterize human mobility in China across all six different types of days. However, there is still an urgent need for development of more dedicated models for human mobility on weekends and different types of holidays.


Author(s):  
Aldona Kipāne

The article gives an insight into criminological problems of bullying in school phenomena. Although the term “bullying” is a modern word, such behaviour has been known for a long time. Bullying is a manifestation of violent behaviour, which threatens the victim's health and safety. The aim of this article is to describe and analyse bullying as a form of expression of violence, showing the criminological aspects of this phenomenon. To achieve the aim of the article the following tasks are defined: to provide the theoretical and practical framework of the research phenomenon, to study and evaluate certain elements of the criminological characterization of the bullying: the description of a victim and a perpetrator, the evaluation of factors and directions of prevention. Theoretical analysis methods such as deconstruction, descriptive and complex analysis, and empirical research methods – document analysis, comparison and compilation were employed in this study.


2017 ◽  
Vol 2643 (1) ◽  
pp. 139-159 ◽  
Author(s):  
Shu Yang ◽  
Chengchuan An ◽  
Yao-Jan Wu ◽  
Jingxin Xia

Travel time reliability (TTR) is an important performance indicator for transportation systems. TTR can be generally categorized as either segment based or origin–destination (O-D) based. A primary difference between the two TTR estimations is that route information is implied in segment-based TTR estimations. Segment-based TTR estimations have been widely studied in previous research; however, O-D–based TTR estimations are used infrequently. This paper provides detailed insight into O-D–based TTR estimations and raises three new issues: ( a) How many routes do travelers usually take and what are the TTR values associated with these routes? ( b) Do statistical differences exist between route-specific and non-route-specific (NRS) TTR values? ( c) How can O-D–based TTR information be delivered? Two processes were proposed to address the issues. Three TTR measures—standard deviation, coefficient of variation, and buffer index—were calculated. The bootstrapping technique was used to measure the accuracy of the TTR measures. Approximate confidence intervals were used to investigate statistically the differences between route-specific and NRS TTR measures. A large quantity of taxicab GPS-based data provided data support for estimating O-D–based TTR measures. The results of O-D–based TTR measures showed that no statistically significant differences existed between route-specific and NRS TTR measures for most of the time periods examined. Statistically significant differences could still be found in some time periods. Travelers may take advantage of these differences to choose a more reliable route. Access to both numeric TTR values and route preference, instead of just to TTR information on segments of interest, can be beneficial to travelers in planning an entire trip.


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