Stress can be associated with many physiologicalchanges resulting in significant decrements in human performance.Due to growing interests in alternative and complementary medicine by Westerners,many of the traditions ...Stress can be associated with many physiologicalchanges resulting in significant decrements in human performance.Due to growing interests in alternative and complementary medicine by Westerners,many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles.These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder.However,the potential of yogic breathing on optimizing human performance and overall well-being is not well known.Breathing techniques such as alternate nostril,Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness.Furthermore,yogic breathing is physiologically stimulating and can be described as a natural"technological"solution to optimize human performance which can be categorized into:(1)cognitive function(i.e.,mind,vigilance);and(2)physical performance(i.e.,cardiorespiratory,metabolism,exercise,whole body).Based on previous studies,we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function.This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state(i.e.,hypertension,depression,dementia)or acute state(i.e.,massive hemorrhage,panic attic)of medical conditions.However,additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation(i.e.,breath-based,mantra,mindfulness)on human performance.These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation.While it has been suggested that breath-based meditation is easier for beginning practitioners when compared to other forms of meditation more research is needed to elucidate these observations.A breath-based meditation sequence suchas Sudarshan Kriya has the potential to help develop an individual’s self-awareness and support better integration of the brain(i.e.,mind)with other organ systems(i.e.,body)for enhanced human performance.展开更多
In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low...In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low oil/gas column height, multiple thin hydrocarbon layers, and distribution in overlapping and connection, and so on. The advantageous conditions for large-area accumulation of low-medium abundance hydrocarbon reservoirs include： （1） large （fan） delta sandbodies are developed in the hinterland of large flow-uncontrolled lake basins and they are alternated with source rocks extensively in a structure like ＂sandwiches＂; （2） effective hydrocarbon source kitchens are extensively distributed, offering maximum contact chances with various sandbodies and hydrocarbon source rocks; （3） oil and gas columns are low in height, hydrocarbon layers are mainly of normal-low pressure, and requirements for seal rock are low; （4） reservoirs have strong inheterogeneity and gas reservoirs are badly connected; （5） the hydrocarbon desorption and expulsion under uplifting and unloading environments cause widely distributed hydrocarbon source rocks of coal measures to form large-area reservoirs; （6） deep basin areas and synclinal areas possess reservoir-forming dynamics. The areas with great exploration potential include the Paleozoic and Mesozoic in the Ordos Basin, the Xujiahe Formation in Dachuanzhong in the Sichuan basin, deep basin areas in the Songliao basin etc. The core techniques of improving exploration efficiency consist of the sweetspot prediction technique that focuses on fine characterization of reservoirs, the hydrocarbon layer protecting and high-speed drilling technique, and the rework technique for enhancing productivity.展开更多
The study had as objective to investigate the land use/land cover change from 1980 to 2019 in the Dja Biosphere Reserve using GIS and remote sensing techniques and the evolution of agroforestry practices. Semi structu...The study had as objective to investigate the land use/land cover change from 1980 to 2019 in the Dja Biosphere Reserve using GIS and remote sensing techniques and the evolution of agroforestry practices. Semi structured questionnaires were administered to 320 farmers who were randomly selected from 35 villages of the Dja Biosphere Reserve characterized by the presence of agroforestry systems. The land use map revealed six classes which were dense humid forest, perennial crop-based agroforestry practices, river, wetland, built up and bare areas. Between 1980 and 2008, dense humid forest lost -4.9% of its area to the benefits of perennial crop-based agroforestry practices, built up and bare land. Between 2008 and 2019, dense humid forest gain 1.77% of its area due to increase in perennial crop-based agroforestry practices and a subsequent increase in vegetation cover. Perennial crop-based agroforestry practices and built up increase progressively from 1980 to 2019. Farmers perceived hunting (36.3%), slash and burn agriculture (43.3%) and harvesting of tree-based products (20.3%) as the anthropogenic activities impacting the reserve negatively. The evolution of agroforestry practices were observed on the field, but the precise area under agroforestry practices in the study area need to be estimated. As a mitigation strategy to livelihood needs as well as the rehabilitation of degraded land, the conversion of pure cultivated agricultural land into agroforestry is a major opportunity.展开更多
Reliable information about soil conservation capacities of different natural ecosystems is an important reference for the design of targeted erosion and sediment control strategies. The objective of this paper is to q...Reliable information about soil conservation capacities of different natural ecosystems is an important reference for the design of targeted erosion and sediment control strategies. The objective of this paper is to quantify the soil conservation capacities of different natural ecosystems that can represent dif-ferent climatic zones. The 137Cs technique has been used to estimate soil redistribution rates in differ-ent natural ecosystems over the past 40 years in Wolong Nature Reserve. The reserve, transiting from the Chengdu plain to the Qinghai-Tibet plateau, maintains rich ecosystems from subtropical to frigid. The net soil erosion rates of 5 selected ecosystems that represent a warm coniferous-broadleaf-mixed forest, a cold-resistant deciduous taiga forest, a cold-resistant shrub, an evergreen cold-resistant taiga forest, and an alpine meadow are 0.17, 0.16, 0.13, 0.11 and 0.06 kg·m-2·a-1, respectively. Their soil con-servation capacities are reversed in order. The reference inventories for ^(137)Cs in different ecosystems range from 1658 to 3707 Bq·m-2 with the altitude. Results of this study indicate that any attempt to de-velop effective erosion and sediment strategies in areas with similar climates should consider natural ecosystem types.展开更多
Background:Fractional flow reserve (FFR) has become an increasingly important index when making decisions with respect to revascularization of coronary artery stenosis.However,the pressure guidewire used in obtaining ...Background:Fractional flow reserve (FFR) has become an increasingly important index when making decisions with respect to revascularization of coronary artery stenosis.However,the pressure guidewire used in obtaining FFR measurements is difficult to control and manipulate in certain complex coronary artery lesions,resulting in increased fluoroscopy time and contrast dye usage.This study examined a novel (NOV) technique for obtaining FFR measurements in hope of easing the difficulties associated with evaluating and treating complex coronary artery lesions.Methods:Fifty-six patients with complex coronary artery lesions were assigned to a conventional (CON) FFR technique group or a NOV FFR technique group.The NOV technique involved the use of a balloon and wire exchange within the coronary artery.The fluoroscopy time,contrast dye usage,and FFR-related complications were assessed after completing the FFR measurement procedure for each patient.Results:The median time required for fluoroscopy in the NOV technique group was significantly less than that in the CON technique group; additionally,lesser amounts of contrast dye were used in the NOV technique group (both P ＜ 0.05).The NOV technique was successfully performed in thirty patients,without any FFR-related complications.However,the CON technique failed in three patients,including two who experienced coronary artery spasms (P ＞ 0.05).Conclusions:Compared to the CON technique used for measuring FFR,the new technique reduced the fluoroscopy time and amount of contrast dye used when evaluating complex coronary artery lesions.The new technique did not increase the risk of operation or decrease the success rate.展开更多
文摘Stress can be associated with many physiologicalchanges resulting in significant decrements in human performance.Due to growing interests in alternative and complementary medicine by Westerners,many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles.These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder.However,the potential of yogic breathing on optimizing human performance and overall well-being is not well known.Breathing techniques such as alternate nostril,Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness.Furthermore,yogic breathing is physiologically stimulating and can be described as a natural"technological"solution to optimize human performance which can be categorized into:(1)cognitive function(i.e.,mind,vigilance);and(2)physical performance(i.e.,cardiorespiratory,metabolism,exercise,whole body).Based on previous studies,we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function.This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state(i.e.,hypertension,depression,dementia)or acute state(i.e.,massive hemorrhage,panic attic)of medical conditions.However,additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation(i.e.,breath-based,mantra,mindfulness)on human performance.These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation.While it has been suggested that breath-based meditation is easier for beginning practitioners when compared to other forms of meditation more research is needed to elucidate these observations.A breath-based meditation sequence suchas Sudarshan Kriya has the potential to help develop an individual’s self-awareness and support better integration of the brain(i.e.,mind)with other organ systems(i.e.,body)for enhanced human performance.
文摘In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low oil/gas column height, multiple thin hydrocarbon layers, and distribution in overlapping and connection, and so on. The advantageous conditions for large-area accumulation of low-medium abundance hydrocarbon reservoirs include： （1） large （fan） delta sandbodies are developed in the hinterland of large flow-uncontrolled lake basins and they are alternated with source rocks extensively in a structure like ＂sandwiches＂; （2） effective hydrocarbon source kitchens are extensively distributed, offering maximum contact chances with various sandbodies and hydrocarbon source rocks; （3） oil and gas columns are low in height, hydrocarbon layers are mainly of normal-low pressure, and requirements for seal rock are low; （4） reservoirs have strong inheterogeneity and gas reservoirs are badly connected; （5） the hydrocarbon desorption and expulsion under uplifting and unloading environments cause widely distributed hydrocarbon source rocks of coal measures to form large-area reservoirs; （6） deep basin areas and synclinal areas possess reservoir-forming dynamics. The areas with great exploration potential include the Paleozoic and Mesozoic in the Ordos Basin, the Xujiahe Formation in Dachuanzhong in the Sichuan basin, deep basin areas in the Songliao basin etc. The core techniques of improving exploration efficiency consist of the sweetspot prediction technique that focuses on fine characterization of reservoirs, the hydrocarbon layer protecting and high-speed drilling technique, and the rework technique for enhancing productivity.
文摘The study had as objective to investigate the land use/land cover change from 1980 to 2019 in the Dja Biosphere Reserve using GIS and remote sensing techniques and the evolution of agroforestry practices. Semi structured questionnaires were administered to 320 farmers who were randomly selected from 35 villages of the Dja Biosphere Reserve characterized by the presence of agroforestry systems. The land use map revealed six classes which were dense humid forest, perennial crop-based agroforestry practices, river, wetland, built up and bare areas. Between 1980 and 2008, dense humid forest lost -4.9% of its area to the benefits of perennial crop-based agroforestry practices, built up and bare land. Between 2008 and 2019, dense humid forest gain 1.77% of its area due to increase in perennial crop-based agroforestry practices and a subsequent increase in vegetation cover. Perennial crop-based agroforestry practices and built up increase progressively from 1980 to 2019. Farmers perceived hunting (36.3%), slash and burn agriculture (43.3%) and harvesting of tree-based products (20.3%) as the anthropogenic activities impacting the reserve negatively. The evolution of agroforestry practices were observed on the field, but the precise area under agroforestry practices in the study area need to be estimated. As a mitigation strategy to livelihood needs as well as the rehabilitation of degraded land, the conversion of pure cultivated agricultural land into agroforestry is a major opportunity.
基金Supported by the National Natural Science Foundation of China (Grant No. 40321101)
文摘Reliable information about soil conservation capacities of different natural ecosystems is an important reference for the design of targeted erosion and sediment control strategies. The objective of this paper is to quantify the soil conservation capacities of different natural ecosystems that can represent dif-ferent climatic zones. The 137Cs technique has been used to estimate soil redistribution rates in differ-ent natural ecosystems over the past 40 years in Wolong Nature Reserve. The reserve, transiting from the Chengdu plain to the Qinghai-Tibet plateau, maintains rich ecosystems from subtropical to frigid. The net soil erosion rates of 5 selected ecosystems that represent a warm coniferous-broadleaf-mixed forest, a cold-resistant deciduous taiga forest, a cold-resistant shrub, an evergreen cold-resistant taiga forest, and an alpine meadow are 0.17, 0.16, 0.13, 0.11 and 0.06 kg·m-2·a-1, respectively. Their soil con-servation capacities are reversed in order. The reference inventories for ^(137)Cs in different ecosystems range from 1658 to 3707 Bq·m-2 with the altitude. Results of this study indicate that any attempt to de-velop effective erosion and sediment strategies in areas with similar climates should consider natural ecosystem types.
文摘Background:Fractional flow reserve (FFR) has become an increasingly important index when making decisions with respect to revascularization of coronary artery stenosis.However,the pressure guidewire used in obtaining FFR measurements is difficult to control and manipulate in certain complex coronary artery lesions,resulting in increased fluoroscopy time and contrast dye usage.This study examined a novel (NOV) technique for obtaining FFR measurements in hope of easing the difficulties associated with evaluating and treating complex coronary artery lesions.Methods:Fifty-six patients with complex coronary artery lesions were assigned to a conventional (CON) FFR technique group or a NOV FFR technique group.The NOV technique involved the use of a balloon and wire exchange within the coronary artery.The fluoroscopy time,contrast dye usage,and FFR-related complications were assessed after completing the FFR measurement procedure for each patient.Results:The median time required for fluoroscopy in the NOV technique group was significantly less than that in the CON technique group; additionally,lesser amounts of contrast dye were used in the NOV technique group (both P ＜ 0.05).The NOV technique was successfully performed in thirty patients,without any FFR-related complications.However,the CON technique failed in three patients,including two who experienced coronary artery spasms (P ＞ 0.05).Conclusions:Compared to the CON technique used for measuring FFR,the new technique reduced the fluoroscopy time and amount of contrast dye used when evaluating complex coronary artery lesions.The new technique did not increase the risk of operation or decrease the success rate.
