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61.
新的谷仓建好之后,旧谷仓就废弃了。委托人是在斯特利亚的拉姆绍达切斯坦经营有机食物生产。他拆除了部分谷仓,并根据生态标准修建一个废墟地花园。花园坐落在海平面偏南920m的地方,能够看到陶恩山脉。设计师整合了现存建筑使用的材料、本地建筑材料和谷仓的残余墙面,重新修建了一个小庭院。墙上设置有三面木围篱,形成了休憩区和全天候沙盒。旧的肥料坑现被当作雨水蓄水池使用。干燥的泥沙石混合层成为培育毛蕊花、扁柏、大戟、百里香和常见牛舌草的温床。而在墙顶等养料相对缺乏的地方,添加的低肥泥层让锦葵、雏菊、  相似文献   
62.
The chemical analysis of the compounds present in dichloromethane and ethanolic fractions as well as bioassays enable to understand the differences in the durability of Eperua falcata and Eperua grandiflora. The main distinction between these two species is the acidic subfraction of diterpenoid extract, which is antifungal in Eperua falcata when tested under in-vitro conditions. This study also shows that ethanolic fraction plays an important role in the mechanism of natural durability. Furthermore, it reports the first isolation of cativic acid in Eperua falcata wood.  相似文献   
63.
Motion sickness, console video games, and head-mounted displays   总被引:1,自引:0,他引:1  
OBJECTIVE: We evaluated the nauseogenic properties of commercial console video games (i.e., games that are sold to the public) when presented through a head-mounted display. BACKGROUND: Anecdotal reports suggest that motion sickness may occur among players of contemporary commercial console video games. METHODS: Participants played standard console video games using an Xbox game system. We varied the participants' posture (standing vs. sitting) and the game (two Xbox games). Participants played for up to 50 min and were asked to discontinue if they experienced any symptoms of motion sickness. RESULTS: Sickness occurred in all conditions, but it was more common during standing. During seated play there were significant differences in head motion between sick and well participants before the onset of motion sickness. CONCLUSION: The results indicate that commercial console video game systems can induce motion sickness when presented via a head-mounted display and support the hypothesis that motion sickness is preceded by instability in the control of seated posture. APPLICATION: Potential applications of this research include changes in the design of console video games and recommendations for how such systems should be used.  相似文献   
64.
In multi-component systems, individual components must be assigned to the tasks that they are to perform. In many applications, there are several possible task decompositions that could be used to achieve the task, and there are limited resources available throughout the system. We present a technique for making task assignments under these conditions. Constraint satisfaction is used to assign components to particular tasks. Heuristics suggest a task decomposition for which an assignment can be found efficiently. We have applied our technique to the problem of task assignment in systems of underwater robots and instrument platforms working together to collect data in the ocean.  相似文献   
65.
Objective: This article examines the unique effects of multiple forms of victimization, namely child abuse and neglect (CAN) and exposure to parental intimate partner violence (IPV), on children's self-blame, feelings of being threatened, self-esteem, and ability to control anger. Method: The cross-sectional study recruited a population-based sample of 2,062 children aged 12–17 years in Hong Kong. Structured questionnaires were used to collect data from the children. The prevalence rate of the co-occurrence of exposure to IPV and CAN in the Chinese population, and the unique impacts of exposure to IPV and CAN on children were examined. Results: The results show that 13.1% of the children had experienced CAN, and 6.5% had witnessed parental IPV. Among those families characterized by IPV, 61.1% were involved in child abuse in the preceding year of the study. Participants who had experienced both CAN and exposure to parental IPV reported lower levels of self-esteem and higher rates of being aggressive and violent, and feeling threatened. These children also reported the highest levels of feeling that their well-being was threatened and of blaming themselves for parental violence and parental discipline. Conclusions: The findings reemphasize the important need for public policy on child and youth victimization that encourages social workers and Child Protective Services to screen for child polyvictimization in cases of suspected/reported child abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive developmental and epileptic encephalopathy caused by pathogenic variants in the ALDH7A1 gene (PDE-ALDH7A1), which mainly has its onset in neonates and infants. Early diagnosis and treatment are crucial to prevent severe neurological sequelae or death. Sensitive, specific, and stable biomarkers for diagnostic evaluations and follow-up examinations are essential to optimize outcomes. However, most of the known biomarkers for PDE lack these criteria. Additionally, there is little discussion regarding the interdependence of biomarkers in the PDE-ALDH7A1 metabolite profile. Therefore, the aim of this study was to understand the underlying mechanisms in PDE-ALDH7A1 and to discover new biomarkers in the plasma of patients using global metabolomics. Plasma samples from 9 patients with genetically confirmed PDE-ALDH7A1 and 22 carefully selected control individuals were analyzed by ultra high performance liquid chromatography–high-resolution mass spectrometry (UHPLC-HRMS). Two novel and reliable pyridoxine-independent diagnostic markers, 6-hydroxy-2-aminocaproic acid (HACA) and an isomer of C9H11NO4, were identified. Furthermore, a possible reaction mechanism is proposed for HACA. This study demonstrates the capability of global metabolomics in disease screening to detect established and novel biomarkers.  相似文献   
67.
To study mechanisms involved in fertility, many experimental assays are conducted by incubating spermatozoa in the presence of molecules dissolved in solvents such as ethanol (EtOH) or dimethyl sulfoxide (DMSO). Although a vehicle control group is usually included in such studies, it does not allow to evaluate the intrinsic effect of the solvent on sperm parameters and its potential influence on the outcome of the experiment. In the present study, we incubated human spermatozoa for 4 h in a capacitation medium in the absence or the presence of different concentrations of EtOH and DMSO (0.1, 0.5, 1.0, and 2.0%) to assess the impact of these solvents on sperm motility, vitality, capacitation, and acrosome integrity. The presence of statistically significant relationships between increasing solvent concentrations and the investigated parameters was assessed using linear mixed models. A significant effect was observed with both solvents for total and progressive sperm motilities. We also evaluated the effect of time for these parameters and showed that the influence of the solvents was stable between 0 and 4 h, indicating an almost direct impact of the solvents. While EtOH did not influence sperm vitality and acrosome integrity, a significant effect of increasing DMSO concentrations was observed for these parameters. Finally, regarding capacitation, measured via phosphotyrosine content, although a dose-dependent effect was observed with both solvents, the statistical analysis did not allow to precisely evaluate the intensity of the effect. Based on the results obtained in the present study, and the corresponding linear mixed models, we calculated the concentration of both solvents which would result in a 5% decline in sperm parameters. For EtOH, these concentrations are 0.9, 0.7, and 0.3% for total motility, progressive motility, and capacitation, respectively, while for DMSO they are 1.5, 1.1, >2, 0.3 and >2% for total motility, progressive motility, vitality, capacitation, and acrosome integrity, respectively. We recommend using solvent concentrations below these values to dissolve molecules used to study sperm function in vitro, to limit side effects.  相似文献   
68.
Journal of Porous Materials - An optically transparent and thermally insulating (OTTI) silica aerogel demonstrates promising results for various solar thermal applications, particularly...  相似文献   
69.
Mesenchymal stem cells (MSCs) can differentiate into osteoblasts, and therapeutic targeting of these cells is considered both for malignant and non-malignant diseases. We analyzed global proteomic profiles for osteoblasts derived from ten and MSCs from six healthy individuals, and we quantified 5465 proteins for the osteoblasts and 5420 proteins for the MSCs. There was a large overlap in the profiles for the two cell types; 156 proteins were quantified only in osteoblasts and 111 proteins only for the MSCs. The osteoblast-specific proteins included several extracellular matrix proteins and a network including 27 proteins that influence intracellular signaling (Wnt/Notch/Bone morphogenic protein pathways) and bone mineralization. The osteoblasts and MSCs showed only minor age- and sex-dependent proteomic differences. Finally, the osteoblast and MSC proteomic profiles were altered by ex vivo culture in serum-free media. We conclude that although the proteomic profiles of osteoblasts and MSCs show many similarities, we identified several osteoblast-specific extracellular matrix proteins and an osteoblast-specific intracellular signaling network. Therapeutic targeting of these proteins will possibly have minor effects on MSCs. Furthermore, the use of ex vivo cultured osteoblasts/MSCs in clinical medicine will require careful standardization of the ex vivo handling of the cells.  相似文献   
70.
Glioblastoma is one of the most common and lethal types of primary brain tumor. Despite aggressive treatment with chemotherapy and radiotherapy, tumor recurrence within 6–9 months is common. To overcome this, more effective therapies targeting cancer cell stemness, invasion, metabolism, cell death resistance and the interactions of tumor cells with their surrounding microenvironment are required. In this study, we performed a systematic review of the molecular mechanisms that drive glioblastoma progression, which led to the identification of 65 drugs/inhibitors that we screened for their efficacy to kill patient-derived glioma stem cells in two dimensional (2D) cultures and patient-derived three dimensional (3D) glioblastoma explant organoids (GBOs). From the screening, we found a group of drugs that presented different selectivity on different patient-derived in vitro models. Moreover, we found that Costunolide, a TERT inhibitor, was effective in reducing the cell viability in vitro of both primary tumor models as well as tumor models pre-treated with chemotherapy and radiotherapy. These results present a novel workflow for screening a relatively large groups of drugs, whose results could lead to the identification of more personalized and effective treatment for recurrent glioblastoma.  相似文献   
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