LiNbO_3:Cr:ZnO晶体生长和光谱特性的研究

采用提拉法从近化学计量比的熔体中生长出尺寸为20mm×50mm的优质LiNbO3:Cr:ZnO(CZLN)晶体,其光学均匀度为7.59(10-5)。进行了吸收和荧光光谱的测定研究。吸收谱测试表明:Cr3+离子在晶体中有2个宽且强的吸收带及1个微弱的吸收线,两宽带中心波长分别为480和660nm,对应于4A2→4T1和4A2→4T2两个具有相同的总自旋能级之间的跃迁,在4A2→4T2吸收宽带的长波边缘处有个很小的吸收峰,其波长为727nm,对应于4A2→2E(R线)的跃迁。荧光测试表明:当激发波长为660nm时,CZLN晶体荧光宽带和1个较弱的荧光线峰并存,宽带范围为802～988nm,峰值波长为871nm,对应于4T2→2E,4A2的联合能级跃迁,荧光线峰波长约为754nm,其强度较弱,相应于2E→4A2(零声子线)能级跃迁。计算了晶场强度和Racah参数,其DqB=2.72,晶体属于强场介质。研究表明,CZLN晶体具备可调谐激光晶体的基本光谱要求,且有良好的物化性能,可以实现宽频带可调谐激光输出。它又具有较大的倍频系数,有望实现420nm附近紫外的自倍频激光输出。

自然与人工——20世纪以来法国风景园林概述

历史上在欧洲同时存在着2种不同对待自然的态度,2种自然观。第一种是模糊的人与自然一体,第二种是以笛卡尔为代表的两分法。从这2种自然观出发,以自然和人工2种哲学艺术倾向为主线,从19世纪末的印象画派园林到20世纪后期的"竖直园林",直至今天的"文化景观",阐述了法国不同风格园林对自然的不同处理、表达方式,论述了20世纪至今法国风景园林的设计及其思潮等。

Cr^(3+):LiNbO_3晶体生长和光谱特性的研究

采用提拉法从近化学计量比的熔体中生长出尺寸为φ20mm×60mm的优质LiNbO3:Cr (CLN)晶体,其光学均匀度为7.05E-005.进行了吸收和荧光光谱的测定研究.吸收谱测试表明:Cr3+离子在晶体中有两个宽且强的吸收带及两个微弱的吸收线,两宽带中心波长分别为481和657nm,对应于4A2→4T1和4A2→4T2两个具有相同的总自旋能级之间的跃迁,在4A2→4T2吸收宽带的长波边缘处有个很小的吸收峰,其波长为727nm,对应于4A2→2E(R 线)的跃迁.荧光测试表明:当激发波长为660nm时,CLN晶体荧光宽带和一个较弱的荧光线峰并存,宽带范围为800—982nm,峰值波长为870nm,对应于4T2→2E,4A2的联合能级跃迁,荧光线峰波长约为752nm,其强度较弱,相应于2E→4A2(零声子线)能级跃迁.计算了晶场强度和Racah参数,其Dq,B,C大小分别为1522.1、542.5和3218.7cm-1,Dq/B=2.81, 晶体属于强场介质.研究表明,CLN晶体具备可调谐激光晶体的基本光谱要求,且有良好的物化性能,可以实现宽频带可调谐激光输出.又具有较大的倍频系数,有望实现410nm附近紫外的自倍频激光输出.

基于PCI总线的数据采集系统的开发

0 引言 随着大规模集成电路和计算机技术的飞速发展,数字技术渗透到各个技术领域,但是自然界中大多数的物理信号却是模拟信号,因此,将模拟信号转换成数字信号是进行信号处理和分析的前提.数据采集系统即是完成这样的任务,将采集到的模拟信号转换成计算机能识别的数字信号.

Individual Minke Whale Recognition Using Deep Learning Convolutional Neural Networks

The only known predictable aggregation of dwarf minke whales (Balaenoptera acutorostrata subsp.) occurs in the Australian offshore waters of the northern Great Barrier Reef in May-August each year. The identification of individual whales is required for research on the whales’ population characteristics and for monitoring the potential impacts of tourism activities, including commercial swims with the whales. At present, it is not cost-effective for researchers to manually process and analyze the tens of thousands of underwater images collated after each observation/tourist season, and a large data base of historical non-identified imagery exists. This study reports the first proof of concept for recognizing individual dwarf minke whales using the Deep Learning Convolutional Neural Networks (CNN).The “off-the-shelf” Image net-trained VGG16 CNN was used as the feature-encoder of the perpixel sematic segmentation Automatic Minke Whale Recognizer (AMWR). The most frequently photographed whale in a sample of 76 individual whales (MW1020) was identified in 179 images out of the total 1320 images provid-ed. Training and image augmentation procedures were developed to compen-sate for the small number of available images. The trained AMWR achieved 93% prediction accuracy on the testing subset of 36 positive/MW1020 and 228 negative/not-MW1020 images, where each negative image contained at least one of the other 75 whales. Furthermore on the test subset, AMWR achieved 74% precision, 80% recall, and 4% false-positive rate, making the presented approach comparable or better to other state-of-the-art individual animal recognition results.

Identification and Physiochemical Analysis of ERK Interacting Proteins Using Bio-Computational Tools

ERK (Extracellular Signal Regulated Kinase) or MAP kinase is an intracellular signaling molecule. ERK is involved in regulation of various functions i.e. cell proliferation, cell migrations, cell survival and many more. It gets activated in response of various stimuli like growth factors, cytokines, virus, second messengers, transforming agents and carcinogens. While transferring signals from cell surface receptors to cell nucleus, ERK interacts with a numbers of proteins. Physiochemical and functional characterization of these proteins is little known. Thus, we attempted to study physiochemical and functional properties of ERK interacting proteins using bio-computational tools. ExPASy and SOSUI server suggested 22 ERK interacting proteins. Physical and chemical parameters of these ERK interacting partners indicated higher percentage of hydrophobic amino acid and leucine as major constituent. Moreover, the instability index indicated that four proteins are stable in over wide range temperature in vitro, and remaining eighteen proteins were found unstable. In addition, SOSUI server showed that fifteen proteins were soluble and six are trans-membrane in nature.

浅议电弧光保护

介绍了弧光的一般特性、产生弧光的原因和危害,讨论了一种新型弧光保护在35kV及以下配电设备上的应用。

Effect of Balanced Application of Potash Fertilizer on the Yield of Rice Yongyou 15 and Soil Nutrient Content

By the field experiment,we set up the treatments of non-application of potash fertilizer,conventional fertilization,balanced fertilization and halved application of potash fertilizer,and studied the effect of different treatments on rice yield and soil nutrient content. The results showed that compared with non-application of potash fertilizer,conventional fertilization and balanced fertilization significantly increased the spike length,thousand kernel weight,yield and total potassium content of the stalk,as well as soil organic matter,total nitrogen and available phosphorus content; compared with conventional fertilization,the balanced fertilization did not significantly increase the rice growth and yield,but effectively increased rice grain total nitrogen,stalk total nitrogen and total phosphorus content,as well as soil available phosphorus and available potassium content. It could be found that potash fertilizer played a certain role in increasing rice yield and soil nutrient content,and the balanced fertilization had the most significant effect.

艺术家与风景园林师对建筑与城市设计的贡献

造型艺术家贝尔纳·拉素斯的作品,以其多专业的尝试而彰显其特性,人们经常只了解其一部分而已。从渡船的设计到高速公路,从工人花园到豪华园林……他形成了一系列的创造手法。同样,部分理论性地,他勾勒出了一条包罗万千可能性的、先于一些艺术创新的具体路径。

Appendectomy for Appendicitis Has Worse Hospital Outcomes in Inflammatory Bowel Disease Patients

Background and Aims: Appendectomy is the choice of surgery for appendicitis but little is known about its outcomes in patients with Inflammatory Bowel Disease (IBD). We sought to compare hospital outcomes of appendectomy for appendicitis between patients with and without IBD. Methods: This is a cross-sectional study utilizing the Nationwide Inpatient Sample between 2009 and 2013. Patients with appendicitis undergoing appendectomy were identified using appropriate International Classification of Diseases codes. Primary outcomes of interest included length of stay (LOS), hospital costs, and post-surgical complications. Univariate and multivariate analyses were used to compare these outcomes between patients with and without IBD. Results: A total of 849,312 patients with appendicitis undergoing appendectomy were included in this study, of which 4261 patients had IBD. IBD patients had longer LOS and increased hospital costs. Crohn’s disease (CD) patients were more likely to develop post-operative pulmonary embolism (adjusted odds ratio (aOR) 7.06, 95% Confidence Interval (CI) (2.19, 22.79)) and anemia (aOR 2.23, 95% CI (1.21, 4.10)), whereas ulcerative colitis patients were more likely to develop post-operative deep vein thrombosis (aOR 9.79, 95% CI (2.41, 39.75)). CD patients were more likely to have perforated ap-pendicitis (aOR 1.37, 95% CI (1.67, 1.11)) and open appendectomy (aOR 1.56, 95% CI (1.96, 1.27)). Conclusions: Appendectomy for appendicitis in IBD patients is associated with adverse hospital outcomes. Focused attempts are needed to decrease the risk of DVT and PE in these patients. Treating patient’s pre-surgical anemia and proactive venous thromboembolism prophylaxis in IBD patients undergoing appendectomy for appendicitis might improve hos-pital outcomes.

Subcutaneous Model for the Study of Dengue Virus Infection in Immune Competent Mice

Various mouse models to study dengue have been described by different authors, some of them using immunodeficient or some using humanized mice. Our group reported previously a deadly murine model, which used the intracranial inoculum of highly virulent Dengue virus (DENV) in immune competent mouse. Here we present a model of immune competent mouse (C57BL/6), infected subcutaneously by the same highly virulent DENV (DENV3 genotype I). In this immunocompetent systemic mice model, the cytokine levels and hematological parameters such as total and differential leukocyte and platelets counts, together with weight loss, were considered important monitoring parameters, allowing a better understanding of the systemic human disease. Mice were inoculated subcutaneously and evaluated by the percentage weight variation as well as the clinical signs. Hematological parameters and cytokines levels were measured and viral titration in brain tissue or serum neutralization was performed to confirm mice infection. The subcutaneously DENV inoculated mice showed weight loss after infection, but they did not show any other clinical signs. The leukocytes and platelets decreased after subcutaneous inoculation. The cytokines TNF alpha and IFN gamma increased after infection in mice. The subcutaneous model provided scope for improved understanding of the dengue pathogenesis, as well as possible mechanism for protection to subsequent mouse infected by intracranial route in mice. This model could be used to study the vertebrate immune response and evaluation of drugs or vaccine against dengue virus.

Physico-Chemical Characterization of Keitt Mango and Cavendish Banana Fruits Produced in Mozambique

Mangoes (Mangifera indica) and bananas (Musa acuminata) are climacteric fruits with a high potential for export due to their exotic aroma and sweet taste. This study aimed to characterize the physical and chemical parameters of Keitt mangoes and Cavendish bananas from different regions of Mozambique. The fruits were collected from Gaza, Manica and Nampula districts of south, central and north parts of Mozambique, respectively. The banana and mango samples were collected in Mid-August 2016 and January 2017, respectively. The fruits collected were at three different maturity stages (green, green-yellowish and yellow). The sample materials were characterised according to their centesimal composition, size, weight, firmness and colour. Analyses of soluble solids and ascorbic acid were, also, performed. The results revealed that the parameters were a good indicator of the maturity stage as well as for multivariate mango and banana applications and consumption. The parameters confirmed that mango fruits with low moisture (green with 83.62%), and fibers (0.44%), high ash (2.05%) crude lipids (0.29%), protein (0.85%) and carbohydrate (13.81%), high total soluble solids (24.60%), and high vitamin C content (14.83 mg/100g) were collected in Nampula with statistic differences (p < 0.05) between region of fruit production in Mozambique and stages of fruit maturity. However, banana fruits with low moisture (73.18%) and fibers (0.27%), high crude proteins (3.44%), ash (0.58%), and crude lipids content (4.92%), high total soluble solids (24.50%) and vitamin C content (2.40 mg/100g) were collected in Manica, where statistic differences (p < 0.05) were reported. This is the first time that Keitt mangoes and Cavendish bananas fruits have been characterized either in relation to the region of production in Mozambique or in relation to the various stages of maturity. This information can be exploited by various actors along the mango and banana value chain.

Analysis of Landscape Patterns and the Trend of Forest Resources in the Three Gorges Reservoir Area

In this paper, first, based on landscape ecology theories, we respectively selected indexes from 4 aspects, area, edge, shape, and density, of the landscape type to describe the status of forest landscape patterns, and we established the stability index of landscape pattern (LSBI). Then, based on geo-statistical theories, we divided the forest in the reservoir area into 3990 grids of 4 km × 4 km using network technology and employing ordinary Kriging modelling to make trend surface analyses of the forest resources in the reservoir area. Finally, based on statistics principles, we used sampling theory to systematically extract 227 samples to obtain 7 periods of remote-sensing data from 1990a to 2012a. Then, we classified and extracted the forest in the sampling area using remote sensing, and we analysed each result with an Autoregressive Integrated Moving Average Model (ARIMA) time-series model. The results indicated the following: 1) the landscape structure of the reservoir area was primarily needle-leaved forest, broad-leaved forest and bush forest, and the mixed stands and bamboo stands were secondary;2) the difference of the forest landscape pattern stability in the reservoir area, in all directions, was not significant, but the southern region was slightly more stable;and 3) the stability of the forest landscape pattern in the reservoir area increased from 1990a to 2012a. It kept increasing until 2016a. This study provides a theoretical basis for the reasonable management and decisions about the forest resources in the Three Gorges Reservoir Area. Meanwhile, it also explores methods for relevant research and has practical significance.

Study on Physical Simulation Test for Pipeline Vulnerability in Case of Landslide

Landslide is one of the most harmful geological disasters for long-distance oil and gas pipelines, and evaluating pipeline vulnerability in case of landslide consequently plays an important role in improving the landslide risk assessment level. To ensure creditability, applicability and operability of pipeline vulnerability evaluation results, a physical simulation test based on the similarity principle was carried out between landslide and pipeline to verify the deformation behavior, stress and strain distribution status of pipeline in case of landslide and to acquire the empirical formula of pipeline vulnerability and distribution of thrust applied on the pipeline by landslide.

<i>Padina pavonica</i>: Morphology and Calcification Functions and Mechanism

Padina pavonica is one of the common macro-algae that inhabit coastal inter-tidal zones around the world. It is one of the two brown algae known to science today that calcifies. It precipitates CaCO3 in the microscopy form of Aragonite needle shape seen macroscopically as a vertical ventral stripes. Here we will summarize the information available since the beginning of the 20th century, taking into consideration the algal distribution, macro and micro-morphology, cytology, reproduction, CaCO3 bio-mineralization, and a slight reference to the commercial aspects, i.e., its use in the medical and cosmetic industries. This paper discusses the likely advantages that Padina gains by the calcification and the effect of pH caused by global climate changes on this calcification. We will describe the distribution of Padina, while focusing on the morphology of P. pavonica, as described in the literature, occasionally comparing it to another common species in Tel-Baruch—P. gymnospora. This review is somewhat prolog for the upcoming research.

Splenectomy in Patient with Splendid Cysts

Introduction: Splenic cysts are uncommon and usually do not generate signs and symptoms, being diagnosed by incidental findings. Case report: A 35-year-old, female patient attended the Luiz Gioseffi Jannuzzi School Hospital (HELGJ) presenting episodes of vomiting and abdominal pain in the left hypochondrium. She was hospitalized for diagnostic investigation. Computed tomography showed the splenic cyst. The procedure was the surgical approach by laparotomy with splenectomy. Histopathological confirmed the diagnosis. Discussion: Compared to the scarce reports in literature, the case described presented typical epidemiology and clinical features. Conclusions: Given the rarity of this pathology cases, it is essential to report these in order to elucidate the specificities and also to discuss diagnostic and therapeutic methods.

Obesity in Relation to Ovarian Response in IVF Treatment

Introduction: The effect of Body Mass Index (BMI), which reflects the woman’s obesity, in IVF treatment cycle, remains unclear. In 1997, the World Health Organization (WHO) provided authoritative refinements to the over-weight terminology and BMI cutoffs [1]. Objective: To verify the relationship between BMI and ovarian response in IVF treatment cycle. Design: Retrospective study. Materials & Methods: The study includes 2625 IVF treatment cycles performed in our IVF center in the period of 4 years. Patients were divided into five groups using the WHO criteria according to their BMI [2]. Cancellation rate, mean last E2 before hCG administration, mean endometrial thickness, mean duration of stimulation, number of eggs retrieved, fertilization rate, pregnancy and abortion rates were analyzed. The unpaired t-test was used in statistical analysis. Results: There was statistically significant less mean oestradiol level prior to hCG, less endometrial thickness and less number of simulation days as BMI gets higher. In contrast, there was a positive relationship between cancellation rate and higher BMI except with BMI >39 which was not, possibly due to lower number of patients available. But if we look at the cause of cancellation, it was 100% due to insufficient number of follicles obtained for this group (BMI >39). Also, days of stimulation are significantly lower for the same group of patients in comparison with the other groups. Retrieval, fertilization and pregnancy rates were not significant between all groups. Abortion rate gets significantly higher as BMI increased. Conclusion: Overweight affects ovulation, if we consider the cause of cancellation being insufficient number of follicles reflects the poor response. The fertilization and pregnancy rate were not affected once oocytes retrieved. The reduction of weight is an important part of infertility treatment in obese women with regards to the ovarian response and abortion rate in IVF cycle.

The Qualitative Analysis for a Class Nonlinear Systems with High Degree

In the paper, the problems of identification of focus or center for a class of nonlinear systems are studied. As results, the identifying rule for the type of singular point of the system and the calculating formula for the focus value are obtained by the classical theory of Poincare and Lyapunov. At the end, the numerical simulation for a polynomial system of seven-degree are showed to corroborate the theoretical results of the method.

Comparative Morphology of the Leaf Epidermis in <i>Ligusticum</i>(Apiaceae) from China

To investigate the taxonomic value of leaf epidermal characters in developing a classification for Ligusticum (Apiaceae), thirty-eight species (including a cultivar) of the genus were examined using both light and scanning electron microscopy. Our results show that the infrageneric classification of Ligusticum based on the characters of involucel bracteoles, mericarps, and pollen grains was not supported as few epidermal characters were relatively constant at section level. Evidence from leaf epidermis, similar to that from molecular and morphological data, supports the separation of Tilingia (i.e. L. ajanense and L. tachiroei) from Ligusticum. Ligusticopsis was found to be indistinguishable from Ligusticum in epidermal characters. Furthermore, results from epidermal analysis, together with that from cytological evidence, fruit morphology as well as molecular phylogenetics suggest that L. delavayi should be transferred out of Ligusticum.

Numerical Analysis of Reinforcement Structure Stability Based on the Stress State of Geogrid

The reinforcement effect of geogrids is exerted through the fixing and occlusion with the surrounding soil to ensure the stability of reinforced structure. Based on the friction reinforced mechanism, the geogrids play the role of anti-shear and anti-pulling. So the indexes of interface strength identified by shear and tensile tests?are?usually used to conduct the stability analysis of reinforced structure. At present, the same indexes of interface strength?areadopted in the stability analysis of reinforced structure, where only one of the anti-shearing action or anti-pulling effect of geogrid is considered, which is separated from the practical stress state of geogrids and has certain limitation. To solve the problem, the paper adjusts the interface indexes of geogrids based on the potential sliding surface and the stress state of geogrids when the failure happens. So the method of stability analysis is concluded where cyclic iterative analysis is carried out till the interface characters of geogrids and the unstable mode of the whole structure are the same. The calculation examples of reinforced soil slope in the paper shows that the method can fully reflect the reinforcement of geogrids and can complete the adoption of numerical method in the stability analysis of reinforcement structure.