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101.
Abstract

The region between Mersin and ?skenderun was selected for studying marine turtles in the Turkish waters of the Mediterranean sea, as the most important nesting grounds of Green Turtles (Chelonia mydas) in the Mediterranean are situated there. In the 1995–96 fishing season, the 5 trawl boats taking part in the project reported that nets in the Eastern Mediterranean trapped 160 Green Turtles and 26 Loggerhead Turtles (Caretta caretta). In the following trawling season (1996/97), 306 Green Turtles, 116 Loggerhead Turtles (Caretta caretta) and 437 Nile Soft-shelled Turtles (Trionyx triunguis) were found to be trapped as a by-catch in the trawling nets. 87% of these turtles were captured by mid-trawling nets, the rest by bottom-trawling nets, mostly at depths of 11–30 m. 95% of all turtles were caught alive and healthy, and were usually released back into the sea immediately after capture by the fishermen. Training measures were given to local fishermen in order to raise their awareness of the threats to marine turtles.  相似文献   
102.
From the results of taxonomic studies, Streptomyces sp. strain No. KT–151 isolated from a soil sample collected in Kumamoto City, was identified as a strain belonging to Streptomyces luteogriseus Schmitz, Deak, Crook and Hooper 1964. A new antibiotic, produced by this strain, was isolated as a leaflet crystal by ion-exchange chromatography and found to be an amino acid with the molecular formula, C5H12N2O2, and named antibiotic KT–151 (refered to as KT–151 hereinafter). The antibiotic showed antimicrobial activity against various Gram-positive and Gram-negative bacteria in a chemically defined medium but it was antagonized by several amino acids such as valine, leucine, isoleucine and threonine.  相似文献   
103.
The bar-headed goose, a specialized high-altitude species, has a capacity for high oxygen uptake from a hypoxic environment. It thus has a higher oxygen affinity than other bird species of lower-altitude environments. Oxygen affinity is determined by molecular structures and genetic mutations of hemoglobin (Hb), which can also influence the coordinating structures and dynamics of oxygen-Hb. To explore the structural differences in Hbs as between high and low altitude species, photolysis dynamic parameters, including quantum yield, enthalpy, and conformational volume changes in carboxy-Hbs (HbCO) for the bar-headed goose and low altitude counterparts (the Chinese goose and chicken) were investigated by the laser pumping-probing technique and photoacoustic calorimetry. Comparing the photolysis results for HbCO of the three species, the enthalpy and conformational volume changes of the bar-headed goose were much smaller than those of the others, although the quantum yields of all three species are similar. To explain the possible mechanisms of these differences, modifications of salt bridges and key residue mutations at the α β subunit interfaces of the proteins are described and discussed briefly.  相似文献   
104.
We report on transient membrane perforation of living cancer cells using plasmonic gold nanoparticles (AuNPs) enhanced single near infrared (NIR) femtosecond (fs) laser pulse. Under optimized laser energy fluence, single pulse treatment (τ = 45 fs, λ = 800 nm) resulted in 77% cell perforation efficiency and 90% cell viability. Using dark field and ultrafast imaging, we demonstrated that the generation of submicron bubbles around the AuNPs is the necessary condition for the cell membrane perforation. AuNP clustering increased drastically the bubble generation efficiency, thus enabling an effective laser treatment using low energy dose in the NIR optical therapeutical window.

Schematic representation of single femtosecond laser pulse plasmonic bubble generation in the vicinity of a cell.  相似文献   

105.
The speed and efficiency of quantum cascade laser‐based mid‐infrared microspectroscopy are demonstrated using two different model organisms as examples. For the slowly moving Amoeba proteus, a quantum cascade laser is tuned over the wavelength range of 7.6 µm to 8.6 µm (wavenumbers 1320 cm–1 and 1160 cm–1, respectively). The recording of a hyperspectral image takes 11.3 s whereby an average signal‐to‐noise ratio of 29 is achieved. The limits of time resolution are tested by imaging the fast moving Caenorhabditis elegans at a discrete wavenumber of 1265 cm–1. Mid‐infrared imaging is performed with the 640 × 480 pixel video graphics array (VGA) standard and at a full‐frame time resolution of 0.02 s (i.e. well above the most common frame rate standards). An average signal‐to‐noise ratio of 16 is obtained. To the best of our knowledge, these findings constitute the first mid‐infrared imaging of living organisms at VGA standard and video frame rate.

  相似文献   

106.
目的:探讨A型肉毒毒素联合CO_2点阵激光治疗眼周皱纹的近期临床疗效。方法:选择2013年6月到2014年6月我院接收眼部皱纹改善手术的患者90例,随机分为激光组、肉毒毒素组及联合治疗组,各30例,分别给予CO_2点阵激光治疗、A型肉毒毒素注射和A型肉毒毒素注射联合CO_2点阵激光治疗。所有患者在治疗后7 d、1月及3月进行疗效随访评价,比较三组不良反应情况。结果:三组患者眼周皱纹均有所改善,治疗1个月时效果最为明显。激光组的静态皱纹治疗效果明显,对动态皱纹治疗效果不明显;肉毒毒素组对动态皱纹治疗效果明显,对静态皱纹治疗效果不明显;联合治疗组对静态皱纹和动态皱纹均有明显的改善,其满意度评价总分数明显高于其他两组。三组患者对CO_2点阵激光和注射A型肉毒毒素所引起疼痛均能耐受,安全性好。结论:A型肉毒毒素联合CO_2点阵激光对静态皱纹和动态皱纹均有明显的改善作用,且不良反应轻,安全性好。  相似文献   
107.
目的:评价飞秒激光辅助全板层角膜移植治疗圆锥角膜患者早期临床效果。方法:回顾性分析。15例17眼圆锥角膜患者均采用飞秒激光辅助联合Anwar大气泡技术暴露后弹力层的角膜移植手术。术前17只眼均测量裸眼视力(Uncorrected visual acuity,UCVA)、最佳矫正视力(Best corrected visual acuity,BCVA)、角膜内皮细胞计数(endothelial cell density,ECD)、角膜中央平均厚度、角膜曲率1(K1)、角膜曲率2(K2)、角膜地形图角膜散光度数和眼压(intraocular pressure,IOP)。所有患者随访时间为术后第1周、第1月、第2月和第3月。结果:到第3月时,UCVA和BCVA均有明显提高。测量中央角膜中央厚度为(493.0±46.80)μm;角膜曲率已接近正常水平,K1和K2平均值分别为(44.56±4.86)D和(40.22±3.60)D,以上数据与术前相比,差异均具有统计学意义(P0.001)。散光值下降至(4.57±3.60)D(P=0.185,P0.05)。角膜内皮细胞丢失率为14.3%。术后眼压均正常。结论:飞秒激光辅助全板层角膜移植治疗圆锥角膜患者早期临床效果明显,具有精确性、安全性和可预测性。  相似文献   
108.
Conserving biodiversity in managed landscapes requires the definition of spatial conservation priorities. The systematic conservation planning tools which are used to define these conservation priorities, assess the vulnerability of different locations by combining two different elements: some measurement of the biological assets in question, and some measurement of the key processes which threaten these biological assets. For instance, in cumulative impact mapping, maps of individual human activities that impact ecosystems (hereafter referred to as ‘stressor’ for individual maps and ‘cumulative stressor’ for combined maps) are overlaid with maps of ecosystem vulnerability, in order to estimate the overall ecological impact of human activities on natural ecosystems. These tools are appealing because they are easy to use and inform regional land planning. However, given that once these spatial conservation priorities are defined they potentially have far-reaching consequences, there is a need to test their robustness and reliability. Here we propose to investigate how the uncertainties related to the estimation of a cumulative stressor layer affect the definition of spatial conservation priorities. We conduct a sensitivity analysis of the different ways of estimating major stressors related to human activities (transport, urbanization and population) with a specific focus on agriculture. We show that spatial conservation priorities are little sensitive to most of the parameters and input data used to estimate the cumulative stressor map. In particular, they are not very sensitive to changes in spatially overlapping stressors, i.e. those which overlap spatially with other stressors. However, our analyses also reveal that spatial conservation priorities are highly sensitive to how the agriculture stressor is defined. These results highlight the importance of better understanding how agricultural activities impact biodiversity and establishing how more accurate information on agricultural practices can be used to define spatial conservation priorities.  相似文献   
109.
110.
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