• Title/Summary/Keyword: desert

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Wind-sand tunnel experiment on the windblown sand transport and sedimentation over a two-dimensional sinusoidal hill

  • Lorenzo Raffaele;Gertjan Glabeke;Jeroen van Beeck
    • Wind and Structures
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    • v.36 no.2
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    • pp.75-90
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    • 2023
  • Turbulent wind flow over hilly terrains has been extensively investigated in the scientific literature and main findings have been included in technical standards. In particular, turbulent wind flow over nominally two-dimensional hills is often adopted as a benchmark to investigate wind turbine siting, estimate wind loading, and dispersion of particles transported by the wind, such as atmospheric pollutants, wind-driven rain, windblown snow. Windblown sand transport affects human-built structures and natural ecosystems in sandy desert and coastal regions, such as transport infrastructures and coastal sand dunes. Windblown sand transport taking place around any kind of obstacle is rarely in equilibrium conditions. As a result, the modelling of windblown sand transport over complex orographies is fundamental, even if seldomly investigated. In this study, the authors present a wind-sand tunnel test campaign carried out on a nominally two-dimensional sinusoidal hill. A first test is carried out on a flat sand fetch without any obstacle to assess sand transport in open field conditions. Then, a second test is carried out on the hill model to assess the sand flux overcoming the hill and the morphodynamic evolution of the sand sedimenting over its upwind slope. Finally, obtained results are condensed into a dimensionless parameter describing its sedimentation capability and compared with values resulting from other nominally two-dimensional obstacles from the literature.

Immunogenic cell death in cancer immunotherapy

  • Minji Choi;Jisoo Shin;Chae-Eun Lee;Joo-Yoon Chung;Minji Kim;Xiuwen Yan;Wen-Hao Yang;Jong-Ho Cha
    • BMB Reports
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    • v.56 no.5
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    • pp.275-286
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    • 2023
  • Cancer immunotherapy has been acknowledged as a new paradigm for cancer treatment, with notable therapeutic effects on certain cancer types. Despite their significant potential, clinical studies over the past decade have revealed that cancer immunotherapy has low response rates in the majority of solid tumors. One of the key causes for poor responses is known to be the relatively low immunogenicity of solid tumors. Because most solid tumors are immune desert 'cold tumors' with antitumor immunity blocked from the onset of innate immunity, combination therapies that combine validated T-based therapies with approaches that can increase tumor-immunogenicity are being considered as relevant therapeutic options. This review paper focuses on immunogenic cell death (ICD) as a way of enhancing immunogenicity in tumor tissues. We will thoroughly review how ICDs such as necroptosis, pyroptosis, and ferroptosis can improve anti-tumor immunity and outline clinical trials targeting ICD. Finally, we will discuss the potential of ICD inducers as an adjuvant for cancer immunotherapy.

The Seeds Characteristics of Artificial Populations of Yellowhorn (Xanthoceras sorbifolium) in China

  • Hyunseok Lee
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.71-71
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    • 2020
  • Xanthoceras sorbifolia Bunge, the sole species in the genus Xanthoceras, is a flowering plant in the family Sapindaceae. It is an important tree species being a source of edible oil and biodiesel with a capacity as a pioneer of degraded and desert land. Seeds of X. sorbifolia were collected from two plantations and two superior trees in Inner Mongolia; and one plantation and one superior tree in Liaoning, China. An inter simple sequence repeat (ISSR) analysis showed genetic variation among four artificial populations in China: two in Inner Mongolia (IM), one in Liaoning (LN), and one in Shandong (SD). The average percentage of polymorphic loci was 81.25 % for these four populations. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. Traits of seeds varied considerably between and among areas, for example two trees produced quite different seeds in several traits although they are adjacent to each other in the same farm. As much attention has not been paid to the traits of seeds, there should be a genetic test to understand this variation. It is necessary to obtain information on seed characteristics first and then provide basic information for further research on the selection of superior trees and provenances.

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Biological Constraints in Algal Biotechnology

  • Torzillo, Giuseppe;Pushparaj, Benjamin;Masojidek, Jiri;Vonshak, Avigad
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.6
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    • pp.338-348
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    • 2003
  • In the past decade, considerable progress has been made in developing the appropriate biotechnology for microalgal mass cultivation aimed at establishing a new agro-industry. This review points out the main biological constraints affecting algal biotechnology outdoors and the requirements for making this biotechnology economically viable. One of them is the availability of a wide variety of algal species and improved strains that favorably respond to varying environmental conditions existing outdoors. It is thus just a matter of time and effort before a new methodology like genetic engineering can and will be applied in this field as well. The study of stress physiology and adaptation of microalgae has also an important application in further development of the biotechnology for mass culturing of microalgae. In outdoor cultures, cells are exposed to severe changes in light and temperature much faster than the time scale re-quired for the cells to acclimate. A better understanding of those parameters and the ability to rapidly monitor those conditions will provide the growers with a better knowledge on how to optimize growth and productivity. Induction of accumulation of high value products is associated with stress conditions. Understanding the physiological response may help in providing a better production system for the desired product and, at a later stage, give an insight of the potential for genetic modification of desired strains. The potential use of microalgae as part of a biological system for bioremediation/detoxification and wastewater treatment is also associated with growing the cells under stress conditions. Important developments in monitoring and feedback control of the culture behavior through application of on-line chlorophyll fluorescence technique are in progress. Understanding the process associated with those unique environmental conditions may help in choosing the right culture conditions as well as selecting strains in order to improve the efficiency of the biological process.

The Effects Attributes of Dessert Cafe Selection on Relationship Quality and Behavioral Intentions (디저트 카페 선택속성이 관계의 질, 행동의도에 미치는 영향)

  • Kim, Young-Kyun
    • Culinary science and hospitality research
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    • v.21 no.6
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    • pp.38-48
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    • 2015
  • This study examined the factors that affect the relationship between dessert cafe customer attribute election, relationship quality and behavioral intention. A total of 260 questionnaires were distributed to consumers, of which 250 were deemed suitable for analysis after the removal of 10 unusable responses. In order to perform statistical analyses required by the study, the SPSS 18.0 Statistical Program was employed for frequency analysis, factor analysis, reliability analysis, correlation, and regression analysis. The results of the exploratory factor analysis showed that three factors regarding attributes selection were extracted from all measurements with a KMO of 0.757 and a total cumulative variance of 67.885%, With regard to relationship quality, three factors were extracted with a total cumulative variance of 76.070% and a KMO score of 0.715. One factor for behavioral intention was extracted that accounted for a total cumulative variance of 66.254% and a KMO score of 0.771. All factors were significant to 0.000 and the correlation between variables was significant. Thus, based on the results, the main research hypothesis that identifies the relationships attributes selection between relationship quality and behavioral intention was partially adopted.

Characterization of Aerosol Concentration during Severe Asian Dust Period at Busan, Korea in 20 March 2010 (2010년 3월 20일 부산지역에 발생한 극심한 황사의 에어로솔 농도 분포 특성)

  • Jung, Woon-Seon;Park, Sung-Hwa;Lee, Dong-In;Kang, Deok-Du;Kim, Dongchul
    • Journal of Environmental Science International
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    • v.23 no.2
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    • pp.275-289
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    • 2014
  • Asian dust (or yellow sand) occurring mainly in spring in East Asia is affected by the distribution of weather systems. This study was performed to investigate the characteristics of suspended particulate for Asian dust at Busan, Korea in 20 March 2010, which was one of the extreme case for the last 10 years. There was used the data of weather chart, satellite, automatic weather system (AWS), $PM_{10}$, laser particle counter (LPC), and backward trajectories model. In synoptically, the high pressure was located in the northwestern part and low pressure was located in the northeastern part of Korea. The strong westerly winds from surface to upper layer makes it possible to move air masses rapidly. Air masses passing through Gobi Desert in Mongolia and Inner Mongolia plateau covered the entire Korean peninsula. As the results of aerosol analysis, $PM_{10}$ concentration at Gudeok mountain in Busan was recorded $2,344{\mu}g/m^3$ in 2300 LST 20 March 2010 and their concentration was markedly increased at coarse mode particle. In surface condition, westerly wind about 3 ~ 5 m/s was dominant and small particles of $0.3{\sim}0.5{\mu}m$ were distributed on the whole. In heavy metal components analysis, the elements from the land was predominated.

Variable Density Yield Model for Irrigated Plantations of Dalbergia sissoo Grown Under Hot Arid Conditions in India

  • Tewari, Vindhya Prasad
    • Journal of Forest and Environmental Science
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    • v.28 no.4
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    • pp.205-211
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    • 2012
  • Yield tables are a frequently used data base for regional timber resource forecasting. A normal yield table is based on two independent variables, age and site (species constant), and applies to fully stocked (or normal) stands while empirical yield tables are based on average rather than fully stocked stands. Normal and empirical yield tables essentially have many limitations. The limitations of normal and empirical yield tables led to the development of variable density yield tables. Mathematical models for estimating timber yields are usually developed by fitting a suitable equation to observed data. The model is then used to predict yields for conditions resembling those of the original data set. It may be accurate for the specific conditions, but of unproven accuracy or even entirely useless in other circumstances. Thus, these models tend to be specific rather than general and require validation before applying to other areas. Dalbergia sissoo forms a major portion of irrigated plantations in the hot desert of India and is an important timber tree species where stem wood is primarily used as timber. Variable density yield model is not available for this species which is very crucial in long-term planning for managing the plantations on a sustained basis. Thus, the objective of this study was to develop variable density yield model based on the data collected from 30 sample plots of D. sissoo laid out in IGNP area of Rajasthan State (India) and measured annually for 5 years. The best approximating model was selected based on the fit statistics among the models tested in the study. The model develop was evaluated based on quantitative and qualitative statistical criteria which showed that the model is statistically sound in prediction. The model can be safely applied on D. sissooo plantations in the study area or areas having similar conditions.

Association between Vegetable, Fruit and Carbohydrate Intake and Breast Cancer Risk in Relation to Physical Activity

  • Kruk, Joanna
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4429-4436
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    • 2014
  • Background: Although the nutritional may exert effect on the breast cancer risk, it is not clear whether the role diet is the same in sedentary and physically active women. The aim of this study was to evaluate the association between fruit, vegetable and carbohydrate intake and the risk of breast cancer among Polish women considering their physical activity level. Materials and Methods: A case-control study was conducted that included 858 women with histological confirmed breast cancer and 1,085 controls, free of any cancer diagnosis, aged 28-78 years. The study was based on a self-administered questionnaire to ascertain physical activity, dietary intake, sociodemographic characteristics, reproductive factors, family history of breast cancer, current weight and high, and other lifestyle factors. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated in unconditional logistic regression analyses including a broad range of potential confounders. Results: With comparison of the highest vs lowest quartile of intake, strong significant associations were observed for total vegetables (OR=0.37, 95%CI=0.20-0.69 P for trend <0.01 and OR=0.53, 95%CI=0.29-0.96, P for trend <0.02), and total fruits (OR=0.47, 95%CI=0.25-0.87, P for trend <0.05 and OR=0.47, 95%CI=0.24-0.90, P for trend <0.02) among women characterized by the lowest and the highest quartile of physical activity. No associations were observed for total carbohydrate intake. Additional analysis showed a positive association for sweets and desert intake among women in the lowest quartile of physical activity (OR=3.49, 95%CI=1.67-7.30, P for trend <0.009) for extreme quartiles of intake comparing to the referent group. Conclusions: The results suggest that a higher consumption of vegetable and fruit may be associated with a decreased risk of breast cancer, especially among women who were low or most physically active throughout their lifetimes. These findings do not support an association between diet high in carbohydrate and breast cancer. However, a higher intake of sweets and deserts may by associated with an increased risk of breast cancer among women who were less physically active.

The motion rule of sand particles under control of the sand transportation engineering

  • Xin, Lin-gui;Cheng, Jian-jun;Chen, Bo-yu;Wang, Rui
    • Wind and Structures
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    • v.27 no.4
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    • pp.213-221
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    • 2018
  • In the desert and Gobi regions with strong wind and large sediment discharge, sand transporting engineering is more effective than sand blocking and sand fixing measures in sand prevention. This study uses the discrete phase model of 3D numerical simulation to study the motion trail, motion state and distribution rule of sand particles with different grain diameters when the included angle between the main shaft of the feather-row lateral transportation sand barrier and the wind direction changes, and conducts a comparison in combination with the wind tunnel test and the flow field rule of common sand barrier. According to the comparison, when wind-sand incoming flow passes through a feather-row sand barrier, sand particles slow down and deposit within the deceleration area under the resistance of the feather-row sand barrier, move along the transportation area formed by the transportation force, and accumulate as a ridge at the tail of the engineering. With increasing wind speed, the eolian erosion of the sand particles to the ground and the feather-row sand barrier is enhanced, and the sand transporting quantity and throw-over quantity of the feather-row sand barrier are both increased. When sand particles with different grain diameters bypass the feather-row sand barrier, the particle size of the infiltrating sands will increase with the included angle between the main shaft of the feather-row sand barrier and the wind direction. The obtained result demonstrates that, at a constant wind speed, the flow field formed is most suitable for the lateral transportation of the wind-drift flow when the included angle between the main shaft of the feather-row sand barrier lateral transportation engineering and the wind speed is less than or equal to $30^{\circ}$.

A Study on the Binding Characteristics of $\beta$-Cyclodextrin with Benzene and Its Application on the Bioremediation ($\beta$-시클로덱스트린($\beta$-Cyclodextrin)의 결합 특성과 벤젠의 생물학적 분해에의 적용에 대한 연구)

  • 최종규;손현석;조경덕
    • Journal of Environmental Health Sciences
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    • v.28 no.5
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    • pp.65-70
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    • 2002
  • Recently, surfactants were frequently used in order to desorb the hydrophobic organic compounds (HOCs) from soil and to enhance the bioavailability. Among them, -cyclodextrin ($\beta$-CD) is one of those. This study was performed to investigate the binding characteristics between benzene and $\beta$-CD and to examine the bioavailability of benzene. First, we investigated binding characteristics between benzene and $\beta$-CD in water and water/soil system. Then, we examined the effect of $\beta$-CD on the biodegradation of benzene in water and water/soil system. Experimental results on the binding characteristics showed that $\beta$-CD resulted in an efficient complex formation with benzene. As -CD concentration increased, the benzene concentration complexed with $\beta$-CD rapidly increased to 30-40% initial benzene added, and reached the equilibrium. We also investigated the effect of $\beta$-CD on the desorption of benzene from soil in the water/soil system. As $\beta$-CD concentration increased, benzene concentration desorbed into water increased up to 90%. How-ever, in its application to biodegradation of benzene in water and water/soil system, the biodegradation rate of benzene did not improved in the presence of $\beta$-CD compared with in the absense of $\beta$-CD. This result indicated that $\beta$-CD was more preferentially used as a carbon source than benzene. Therefore, for remediation of benzene contaminated soils, $\beta$-CD can be used as a surfactant to desert benzene from soil, and then ex-situ chemical treatment can be applied for the remediation.