2,735 research outputs found

    Prospects and limitations of wakefield acceleration in solids

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    Advances in the generation of relativistic intensity pulses with wavelengths in the X-ray regime, through high harmonic generation from near-critical plasmas, opens up the possibility of X-ray driven wakefield acceleration. The similarity scaling laws for laser plasma interaction suggest that X-rays can drive wakefields in solid materials providing TeV/cm gradients, resulting in electron and photon beams of extremely short duration. However, the wavelength reduction enhances the quantum parameter χ\chi, hence opening the question of the role of non-scalable physics, e.g., the effects of radiation reaction. Using three dimensional Particle-In-Cell simulations incorporating QED effects, we show that for the wavelength λ=5\lambda=5\,nm and relativistic amplitudes a0=10a_0=10-100, similarity scaling holds to a high degree, combined with χ1\chi\sim 1 operation already at moderate a050a_0\sim 50, leading to photon emissions with energies comparable to the electron energies. Contrasting to the generation of photons with high energies, the reduced frequency of photon emission at X-ray wavelengths (compared to at optical wavelengths) leads to a reduction of the amount of energy that is removed from the electron population through radiation reaction. Furthermore, as the emission frequency approaches the laser frequency, the importance of radiation reaction trapping as a depletion mechanism is reduced, compared to at optical wavelengths for a0a_0 leading to similar χ\chi.Comment: 9 pages, 7 figure

    Farmers' Practices in Developing Agricultural Land in Malaysia: is There an Islamic Microfinance Solution?

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    Objective – This paper attempts to highlight the farmers' lives in Malaysia and their problems in developing idle agricultural land.Methods - This paper is using descriptive and exploratory method of study which refer to the situation of agricultural sector in Malaysia.Results - The scheme aPLS (agricultural production and loss sharing) that proposed cannot stand alone in the traditional fiqh to be implemented now. Therefore, the combinations of aPLS contract with ujrah principle are really needed. This is important to ensure the flexibility of the contract that can offer a fully comprehensive scheme of Islamic agricultural finance.Conclusion – The land together with labour can be considered as a form of capital and therefore has a similarity to the contracts of mudaraba and musharaka. Hence, it can be said that these principles are “agricultural production and loss sharing (aPLS)” because land will naturally produce an output or a product. Muzara'a and musaqa therefore can be said to be contracts which are based on sharing output rather than sharing profit

    The relationship between nurses' clinical competency and job stress in Ahvaz university hospital, 2013

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    زمینه و هدف: صلاحیت بالینی پرستاری، شایستگی کاربرد همزمان دانش، مهارت، نگرش ها و ارزش ها در مراقبت از بیمار است که به دلیل اهمیت آن اخیراً مورد توجه بیشتری قرار گرفته است. با توجه به اهمیت روز افزون موضوع صلاحیت پرستاری، شناخت عوامل مرتبط با آن و از جمله استرس شغلی ضروری به نظر می رسد؛ لذا مطالعه حاضر با هدف تعیین رابطه صلاحیت بالینی و استرس شغلی پرستاران شاغل در بیمارستان های دانشگاهی شهر اهواز در سال1392 انجام شد. روش بررسی: در این پژوهش توصیفی- تحلیلی که به صورت مقطعی در طی سال 1392 انجام شد، 80 نفر پرستار شاغل در بیمارستان های آموزشی شهر اهواز از طریق نمونه گیری تصادفی انتخاب و وارد مظالعه شدند. ابزار گردآوری داده ها شامل پرسشنامه های استرس شغلی Osipow و پرسشنامه صلاحیت بالینی Benner بود که به صورت خود ایفاء تکمیل گردیدند. میزان صلاحیت بالینی پرستاران ارزیابی و ارتباط آن با استرس شغلی تعیین شد. یافته ها: بیشتر پرستاران (3/81 درصد) دارای استرس شغلی متوسط بودند. میانگین نمره کل صلاحیت بالینی پرستاران 48/18± 15/61 بود. آزمون همبستگی پیرسون نشان داد که بین استرس شغلی و صلاحیت بالینی پرستاران در تمام حیطه های آن همبستگی منفی و معنی داری وجود دارد (01/0>P). همچنین بین میزان استرس شغلی و بکارگیری صلاحیت بالینی کل ارتباط معنی داری وجود داشت (001/0>P). نتیجه گیری: بر اساس نتایج مطالعه حاضر، افزایش استرس شغلی پرستاران با کاهش صلاحیت های بالینی آنها رابطه دارد که بایستی مورد توجه مدیران پرستاری قرار گیرد

    Paramater on Maternal Delivery Referral Process

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    Introduction: The rate of maternal mortality in Indonesia according to 2002–2003 Indonesian Demographic and Health Survey (IDHS) was 307 per 100,000 live births. The direct causes of maternal deaths, among others, are prolonged labor, hemorrhage, infection, and preeclampsia. Referral system includes referring responsibility to better facilitated healthcare sites to obtain more adequate services. However, maternal referral process in Banjar District still faces some problems such as referral health providers with inadequate skills of handling emergency cases, insufficient means of transportation, and no referral letter or partograph. Usually, when referred, the pregnant woman is only accompanied by her family so that she is brought to the referral site without being equipped with infusion. The objective of the study was to evaluate the parameter of maternal delivery referral in Ratu Zalekha Martapura District Hospital. Method: This study used observational study with a cross-sectional study design using quantitative and qualitative approaches. Samples were 107 delivering women referred to hospitals selected with non probability sampling. Data were analyzed with Chi-square (χ) and logistic regression test. Result: Quality maternal referral process resulted in healthy women 78.8%. Post delivery women's health was greater in quality maternal referral process (RP = 2.1; 95% CI = 1.28–3.52). Normal delivery had an opportunity towards post delivery women's health (RP = 1.6; 95% CI = 1.13–2.20). In addition, time needed to reach the referral sites and referral birth attendants were significantly associated with maternal referral process (p = 0.002 and p = 0.002). Meanwhile, women's condition when referred was insignificant statistically. Discussion: Quality maternal referral process could likely improve post delivery women's health.Normal delivery affected the women's health condition

    Uji Validitas dan Reliabilitas Kwesioner Etiologi dan Faktor Risiko Kanker Nasofaring

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    Validity and reliability tests on questionnaires designed for etiology and risk factors of nasopharynx cancerBackground: The etiology and risk factors of NPC is a combination of multi-risk factors of genetic history, lifestyle, environmental exposure, and EBV infection. Currently, there is no publication about NPC's questionnaire. This study analyzed the reliability and validity of the questionnaire of NPC's etiology and risk factors.Methods: The cross-sectional study of the questionnaires of NPC's etiology and risk factors were filled by the used-tryout samples i.e NPC sufferers and their family members, in April to August 2012. The study were done at Anatomical Pathology Laboratory of Kariadi & St. Elisabeth Hospitals Semarang. There are three main constructs, namely; genetic, lifestyle, and environmental exposure. The 74 filled-questionnaires were tested by correlation analysis of product moment for the validity, and the reliability tests conducted with Cronbach's Alpha. The data were analyzed with SPSS for Windows version 17.0.Results: A test for risk family history constructs were valid (p>0.932) and reliabel (Cronbach's Alpha=0.864). A test for lifestyle with a Pearson Correlation were p>0.785 for smoking habit, eating salted fish p>0.793, eating grilled-fish p>0.862, eating pickled p>0.831, drinking alcohol p>0.760, instant noodle p>0.497, food preservation p>0.495, food contains MSG p>0.627, with Cronbach's Alpha>0.751. A test for environmental exposure risk were valid for the exposure to passive cigarette smoke (p>0.486) Cronbach's Alpha=0.789,the exposure of the home environment p>0.658 Cronbach's Alpha=0.832, exposure-related jobs p>0.373 Cronbach's Alpha=0.697, and chronic nasopharingitis are all valid (p>0.900) with Cronbach's Alpha=0851.Conclusions: The questionnaires designed as a tool of NPC's etiology and risk factors are valid and reliable

    Miniaturized Substrate Integrated Waveguide Diplexer Using Open Complementary Split Ring Resonators

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    In this paper, two miniaturized planar diplexers based on the substrate integrated waveguide (SIW) structure loaded by open complementary split-ring resonators (OCSRRs) are proposed. The working principle is based on the theory of evanescent mode propagation. The proposed SIW diplexers operate below the cutoff frequency of the waveguide. Both the complementary split-ring resonators (CSRRs) and the OCSRRs behave as electric dipoles however, the resonance frequency of the OCSRRs is approximately half of the resonance frequency of the CSRRs. Therefore, the electrical size of the OCSRRs is larger than the CSRRs. Accordingly, the OCSRRs are more appropriate for the SIW miniaturization. At first, the filtering response of the SIW structure loaded by OCSRR unit cells is investigated. Then, two miniaturized SIW diplexers which consist of two cascaded OCSRR unit cells with different orientations are designed. For the first diplexer (Type I), the fractional bandwidths of operation for the up and down channels are 9.52% and 2.59% at 4.2 GHz and 5.8 GHz, respectively. For the second diplexer (Type II), the fractional bandwidths of operation for the up and down channels are 5.95% and 2.51% at 4.7 GHz and 5.6 GHz, respectively. Finally, in order to validate the ability of the proposed OCSRR unit cells in the size reduction, two designed diplexers are fabricated and experimental verification are provided. A good agreement between the results of measurement and simulation is achieved. The proposed diplexers show significant advantages in terms of size reduction, low loss, high isolation, and integration with other planar circuits

    Public Knowledge of Oral Cancer and Modelling of Demographic Background Factors Affecting this Knowledge in Khartoum State, Sudan

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    Objectives: Knowledge of oral cancer affects early detection and diagnosis of this disease. This study aimed to assess the current level of public knowledge of oral cancer in Khartoum State, Sudan, and examine how demographic background factors affect this knowledge. Methods: This cross-sectional study involved 501 participants recruited by systematic random sampling from the outpatient records of three major hospitals in Khartoum State between November 2012 and February 2013. A pretested structured questionnaire was designed to measure knowledge levels. A logistic regression model was utilised with demographic background variables as independent variables and knowledge of oral cancer as the dependent variable. A path analysis was conducted to build a structural model. Results: Of the 501 participants, 42.5% had no knowledge of oral cancer, while 5.4%, 39.9% and 12.2% had low, moderate and high knowledge levels, respectively. Logistic regression modelling showed that age, place of residence and education levels were significantly associated with knowledge levels (P = 0.009, 0.017 and <0.001, respectively). According to the structural model, age and place of residence had a prominent direct effect on knowledge, while age and residence also had a prominent indirect effect mediated through education levels. Conclusion: Education levels had the most prominent positive effect on knowledge of oral cancer among outpatients at major hospitals in Khartoum State. Moreover, education levels were found to mediate the effect of other background variables

    Identification of bacteria and fungi in the solid waste generated in hospitals of Sana'a city, Yemen

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    A medical establishment such as hospitals and medical centers generate a sizable amount of hazardous waste. In Yemen, the hospitals' wastes are still largely mismanaged, mainly because the sector did not know what to do with the waste. The present study was undertaken to determine the bacterial and fungal agents present in different various of the hospitals' solid waste. The samples were collected from the different wards/departments and from the central storage rooms/dustbins of the hospitals in Sana'a city, Yemen. The presence of bacterial and fungal agents in the hospitals' waste was determined using the conventional bacteria, and fungi identification methods. The bacteria and fungi were detected in the hospitals' solid waste were Klebsiella spp. (9.3%), E. coli (12.7%), Citrobacter spp. (8.5), Candida spp. (18.6%), Proteus spp. (9.3%), Cladosporium werneckii spp. (19.5%), Bacillus spp. (9.3%), Aspergillus spp. (7.6%), Trichothecium spp. (0.8%), Mucor spp. (3.4%), and Acinetobacter spp. (0.8%). This study results confirmed that the prevalence types of microorganism vary based on seasonal and spatial variables
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