The structure relaxation of carbon nanotube

A simple macroscopic continuum elasticity theory (CET) is used to calculate the structure relaxation of single-wall carbon nanotube (SWNT), an analytic formula is obtained. We also expand an atomic scale three-parameter empirical model [ T. Lenosky {\emph et al.} Nature 355, 333(1992)] in order to correctly describe the bond-length change effects. The structure relaxation of SWNT expected by the model is good in agreement with our CET results, and very well consistent with the previous calculation from a first principles local density function approximation. Using the expanded Lenosky model, we calculate the strain energy of bending tube. The obtained results are good in agreement with the previous theoretical expectation. It shows the model may be a good simple replacement of some more sophisticated methods on determining carbon networks deformations.Comment: 9 pages, 4 eps figure

Energy levels of light atoms in strong magnetic fields

In this review article we provide an overview of the field of atomic structure of light atoms in strong magnetic fields. There is a very rich history of this field which dates back to the very birth of quantum mechanics. At various points in the past significant discoveries in science and technology have repeatedly served to rejuvenate interest in atomic structure in strong fields, broadly speaking, resulting in three eras in the development of this field; the historical, the classical and the modern eras. The motivations for studying atomic structure have also changed significantly as time progressed. The review presents a chronological summary of the major advances that occurred during these eras and discusses new insights and impetus gained. The review is concluded with a description of the latest findings and the future prospects for one of the most remarkably cutting-edge fields of research in science today.Comment: 37 pages, 16 figures, 1 tabl

An epidemiological study of the impact of Toxoplasma gondii and Brucella melitensis on reproduction in sheep and goats in Dohuk Province, Iraq

Brucellosis and toxoplasmosis are very important zoonoses in many countries of the world, including Iraq. These diseases are considered economically important due to the negative effects on reproduction of small ruminants, which are a critical part of livestock enterprises in Iraq. Prior to the study outlined in this thesis, few studies on the epidemiology of brucellosis and toxoplasmosis and their effect on the reproduction in Dohuk Province had been undertaken. Consequently, the aims of the study were to determine the epidemiological characteristics, economic impact, and effect of brucellosis and toxoplasmosis on reproduction in small ruminants in Dohuk Province. A cross-sectional study of 432 small ruminants (335 sheep and 97 goats) belonging to 72 farms in six districts in Dohuk Province, northern Iraq, was undertaken to investigate risk factors associated with brucellosis seropositivity. Sera were tested using the Rose Bengal test (RBT) and an indirect enzyme-linked immunosorbent assay (iELISA). Using parallel interpretation, RBT and iELISA results showed that 31.7% (95% confidence interval (CI): 26.1, 36.3) of sheep and 34.0% (95% CI: 24.7, 44.3) of goats in the study had antibodies against Brucella. A random-effects multivariable logistic regression model indicated that a higher chance of being seropositive (odds ratio (OR) = 1.7; 95% 1.4; 2.2) was associated with an increase in the age of animals. The odds of Brucella seropositivity in flocks where sheep and goats grazed together was 2.0 times higher (95% CI: 1.08; 3.9) compared to flocks where sheep and goats grazed separately. The odds of Brucella seropositivity in small ruminants was 2.2 higher (95% CI: 1.2; 4.3) for animals originating from farms with a history of goat abortion in the preceding 12 months. In contrast, for every 1000 Iraqi Dinars (US$0.85) spent by the farmers on control of Brucella in their flocks, the odds of Brucella seropositivity decreased significantly (OR = 0.9, p-value = 0.021). The final model also indicated significant differences in Brucella seropositivity between the different districts of Dohuk province. The small ruminants were also tested for the presence of antibodies against Toxoplasma gondii, using a latex agglutinin test (LAT) and an indirect enzyme-linked immunosorbent assay (iELISA). When the test results were interpreted in parallel, 42.1$ 0.85) spent by the farmers on the prophylactic treatment in their flocks, the odds of Toxoplasma seropositivity decreased significantly (OR = 0.94; 95% CI 0.90, 0.98). Sera from 240 small ruminants (192 sheep and 48 goats) from 12 farms in Dohuk Province, northern Iraq, were collected to investigate relative risk of pregnancy loss associated with brucellosis and toxoplasmosis seroconversion during pregnancy. All the selected pregnant animals were examined by ultrasonography twice, at the time of blood collection (approximately 2 and 4 months of gestation). For detection of antibodies to Brucella, serum samples were tested using the Rose Bengal test (RBT) and an indirect enzyme-linked immunosorbent assay (iELISA), while the Latex agglutination test (LAT) and an indirect enzyme-linked immunosorbent assay (iELISA) were used to test for Toxoplasma gondii antibodies. There were significance differences in the seroprevalence in sheep and goats at the two sampling times for Brucella and Toxoplasma (P-value = 0.0003 and 0.03 in first and second sampling, respectively). The incidence risk of seroconversion to Brucella over the two months was 10.6% (95% CI: 6.9 -15.3) and 7.3% (95% CI: 4.3 - 11.6) for Toxoplasma. The analysis indicated that animals that seroconverted to Brucella were more likely to lose their pregnancy (OR: 2.9, 95%CI 1.6-5.5). An economic evaluation of mass vaccination programme for brucellosis indicated that the financial loss overall from brucellosis would decrease from 1.75 to 0.55 US$per adult female. The net present value of the mass vaccination program was estimated at US$ 10,564,828 (95% CI: -16,203,454 to 37,049,245), the benefit-cost ratio was estimated to be 4.25 (95% CI: 0 to 11.22), and the internal rate return (IRR) was estimated at 91.38% (95% CI:11.71 to 190.62%). The seroprevalence in small ruminants was predicted to decrease from 9.22 to below 0.73 % after 20 years of the implementation of the proposed mass vaccination program. It is concluded that, identifying the putative risk factors for both pathogens with implementing a mass vaccination program of small ruminants with Rev. 1 for brucellosis will inform the development of more effective control programs to reduce the impact of the infection and advocate for adequate resources to implement the programs

The role of the imams of mosques in preserving the purposes of Sharia through their missionary mission The necessities as a model

The Research in this study has addressed very important issue in the life of Muslims. That Were Preserving necessities can spread the spirit of awareness by the different ways.The researcher found that the role of the imam is very important between Muslims. He can change many of the infractions and evil and protect people\u27s religion, souls, symptoms and other necessities.Therefore, the Imam needs to achieve this to qualify and prepare in various aspects of his career and career

Effect of IFRS adoption and corporate governance practices on performance: A study on listed companies in Dubai

This study has been conducted on the financial market of Dubai. The purpose of the study is to understand the effect of IFRS adoption along with corporate governance characteristics over the financial performance of listed companies in Dubai. The study has taken return on assets as the measurement of performance, while IFRS adoption, board independence, board size, and audit quality as the measurement of CG. Firm size and leverage have been taken as control variables. The data has been collected from the annual reports and websites of the companies. Regression analysis is employed to understand the effect of each independent variable on performance. The study has identified that IFRS adoption; board independence, board size, and audit quality have a significant effect over financial performance of companies listed in Dubai stock market. The major contribution of the study is the combined effect of variables, as in the available literature all these variables have not yet been studied collectively

BIOLOGICALLY INSPIRED OBJECT RECOGNITION SYSTEM

Object Recognition has been a field of interest to many researchers. In fact, it has been referred to as the most important problem in machine or computer vision. Researchers have developed many algorithms to solve the problem of object recognition that are machine vision motivated. On the other hand, biology has motivated researchers to study the visual system of humans and animals such as monkeys and map it into a computational model. Some of these models are based on the feed-forward mechanism of information communication in cortex where the information is communicated between the different visual areas from the lower areas to the top areas in a feed-forward manner; however, the performance of these models has been affected much by the increase of clutter in the scene as well as occlusion. Another mechanism of information processing in the cortex is called the feedback mechanism, where the information from the top areas in the visual system is communicated to the lower areas in a feedback manner; this mechanism has also been mapped into computational models. All these models which are based on the feed-forward or feedback mechanisms have shown promising results. However, during the testing of these models, there have been some issues that affect their performance such as occlusion that prevents objects from being visible. In addition, scenes that contain high amounts of clutter in them, where there are so many objects, have also affected the performance of these models. In fact, the performance has been reported to drop to 74% when systems that are based on these models are subjected to one or both of the issues mentioned above. The human visual system, naturally, utilizes both feed-forward and feedback mechanisms in the operation of perceiving the surrounding environment. Both feed-forward and feedback mechanisms are integrated in a way that makes the visual system of the human outperforms any state-of-the-art system. In this research, a proposed model of object recognition based on the integration concept of the feed-forward and feedback mechanisms in the human visual system is presented

Prediction of nodes mobility in 3-D space

Recently, mobility prediction researches attracted increasing interests, especially for mobile networks where nodes are free to move in the three-dimensional space. Accurate mobility prediction leads to an efficient data delivery for real time applications and enables the network to plan for future tasks such as route planning and data transmission in an adequate time and a suitable space. In this paper, we proposed, tested and validated an algorithm that predicts the future mobility of mobile networks in three-dimensional space. The prediction technique uses polynomial regression to model the spatial relation of a set of points along the mobile node’s path and then provides a time-space mapping for each of the three components of the node’s location coordinates along the trajectory of the node. The proposed algorithm was tested and validated in MATLAB simulation platform using real and computer generated location data. The algorithm achieved an accurate mobility prediction with minimal error and provides promising results for many applications

Mechanical Performance and Thermo-Physical Properties of Cement Mortar Incorporating Hybrid Slags

Owing to the growing environmental pressure to reduce waste and pollution, the effective utilization of industrial solid wastes in construction applications has gained notable attention. This study investigates the mechanical and thermal properties of cement mortars incorporating two types of waste slags. Ferrochrome (FeCr) slag aggregate was used as a replacement for sand at the ratios of 25, 50, 75 and 100 wt. %. Ground granulated blast furnace slag (GGBS) has been used as a partial replacement of cement at the ratio of 25 wt. %. Compressive strength, permeable voids content and thermal conductivity tests have been conducted after 28 days of curing. The microstructure characteristics have been investigated by scanning electron microscope (SEM) equipped with energy dispersive analytical x-ray unit (EDAX). The experimental results revealed that FeCr waste aggregates could satisfactorily replace for natural fine sand in cement mortars up to 25 wt. % without a remarkable degradation of the compressive strength. Furthermore, Increasing replacement ratios of FeCr aggregates over 25 wt. % have resulted in noticeable decrease in thermal conductivity and an increase in the permeable voids content of cement mortars. The integration of GGBS with FeCr aggregates leads to enhanced compressive strength, reduced voids content and contribute to improved microstructure. The developed mortars with comparatively improved thermal resistance can be recommended for several structural and non-structural applications especially in hot weather regions.The authors would like to acknowledge the financial support provided by Sohar Port and Free Zone Company under Sultan Qaboos University Grant No. CR/ENG/ CAED/18/07

The production of hydrolysates from industrially defatted rice bran and its surface image changes during extraction

BACKGROUND This research employed mild-subcritical alkaline water extraction (SAW) technique to overcome the difficulty of active compounds extractability from an industrially defatted rice bran (IDRB). Mild-SAW (pH 9.5, 130 °C, 120 min) treatment, followed by enzymatic hydrolysis (Protease G6) were applied to produce rice bran hydrolysate (RBH). Response surface methodology was used to identify proteolysis conditions for maximizing protein content and ABTS radical scavenging activity (ABTS-RSA). The microstructural changes during the extraction occurring in the IDRB were monitored. The selected RBH was characterised for protein recovery, yield, antioxidant activities, phenolic profile and hydroxymethylfufural (HMF) content. RESULTS Optimal proteolysis conditions were at 20 mL kg-1 IDRB (E/S) for 6 h. Under these conditions, the yield, ABTS-RSA, Ferric reducing antioxidant power and the total phenolic content of the RBH were 46.1%, 294.22 μmol trolox g-1, 57.72 μmol FeSO4 g-1, and 22.73 mg gallic acid g-1, respectively, with relatively low HMF level (0.21 mg g-1). The protein recovery was 4.8 times greater than the recovery obtained by conventional alkaline extraction. Its major phenolic compounds were p-coumaric and ferulic acids. The microstructural changes of IDRB confirmed that the mild-SAW/Protease G6 process enhanced the release of active compounds. CONCLUSION The process of mild-SAW followed by proteolysis promotes the release of active compounds from IDRB

A comparative analysis reveals weak relationships between ecological factors and beta diversity of stream insect metacommunities at two spatial levels

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