2,648 research outputs found
Prospects and limitations of wakefield acceleration in solids
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 , 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 nm and relativistic amplitudes
-100, similarity scaling holds to a high degree, combined with
operation already at moderate , 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
leading to similar .Comment: 9 pages, 7 figure
Hubungan Pola Perdarahan Uterus dengan Kadar Estradiol pada Akseptor Kontrasepsi Injeksi DMPA
Background: Bleeding disturbances are the main complaint that cause most DMPA users discontinuing contraceptive use. Mechanism underlying the bleeding disturbances is not clear. It is presumed that the condition is related to fluctuation of estradiol level or to low persistent estradiol level Objective: 1. To evaluate an association between bleeding pattern and estradiol level of DMPA users after 3, 6, 9, 12 months use. 2. To evaluate an association between estradiol level and length of use. 3. To evaluate an association between bleeding pattern and estradiol level, body mass index (BMI), age, parity, total cholesterol level of DMPA users.Design: Observational study, secondary analysis nested on āRandomized Controlled Trial PlanibuĀ® and Depo ProgestinĀ®āMaterial and Method: Seventy DMPA users received injection every 3 months for 12 months. Before injection was administered, venous blood was taken and examination of estradiol level was done using Enzyme Imuno Absorbent Assay (ELISA). In addition, in-depth interview was also done on bleeding pattern for the last reference period (90 days). Subject was classified according to their bleeding pattern into groups of amenorrhea, oligomenorrhea, spotting, and bleeding,Results: All research subjects indicated low estradiol concentration with an average concentration less than 150 pg/ml. There was a correlation between length of USAge and estradiol level; estradiol level after 12 months of USAge was less than 100 pg/ml. There was no different between bleeding pattern and estradiol in month 3, 6, 9,12 using bivariate analysis with t-test with amenorrhea group as reference and p > 0,05. T-test and Chi Square analyses using amenorrhea group as reference stated that there was no association between bleeding pattern and age, BMI, and parity. Using multivariate analysis with Multinomial Logistic Regression, it was stated that correlation between estradiol concentration and bleeding pattern was not affected by age, body mass index, or total cholesterol level. There was an association between bleeding pattern and cholesterol level using bivariate and multivariate analyses.Conclusion: 1. Estradiol level in various bleeding pattern after 3,6,9,12 month of USAge was not different. 2. There was correlation between low estradiol level and length of USAge. 3. Association between bleeding pattern and estradiol level was not influenced by age, parity and body mass index, and total cholesterol level
Hubungan Pola Perdarahan Uterus dengan Kadar Estradiol pada Akseptor Kontrasepsi Injeksi DMPA
Background: Bleeding disturbances are the main complaint that cause most DMPA users discontinuing contraceptive use. Mechanism underlying the bleeding disturbances is not clear. It is presumed that the condition is related to fluctuation of estradiol level or to low persistent estradiol level Objective: 1. To evaluate an association between bleeding pattern and estradiol level of DMPA users after 3, 6, 9, 12 months use. 2. To evaluate an association between estradiol level and length of use. 3. To evaluate an association between bleeding pattern and estradiol level, body mass index (BMI), age, parity, total cholesterol level of DMPA users.Design: Observational study, secondary analysis nested on āRandomized Controlled Trial PlanibuĀ® and Depo ProgestinĀ®āMaterial and Method:Ā Seventy DMPA users received injection every 3 months for 12 months. Before injection was administered, venous blood was taken and examination of estradiol level was done using Enzyme Imuno Absorbent Assay (ELISA). In addition, in-depth interview was also done on bleeding pattern for the last reference period (90 days). Subject was classified according to their bleeding pattern into groups of amenorrhea, oligomenorrhea, spotting, and bleeding,Results: All research subjects indicated low estradiol concentration with an average concentration less than 150 pg/ml. There was a correlation between length of usage and estradiol level; estradiol level after 12 months of usage was less than 100 pg/ml. There was no different between bleeding pattern and estradiol in month 3, 6, 9,12Ā using bivariate analysis with t-test with amenorrhea group as reference and p > 0,05. T-test and Chi Square analyses using amenorrhea group as reference stated that there was no association between bleeding pattern and age, BMI, and parity. Using multivariate analysis with Multinomial Logistic Regression, it was stated that correlation between estradiol concentration and bleedingĀ pattern was not affected by age, body mass index, or total cholesterol level. There was an association between bleeding pattern and cholesterol level using bivariate and multivariate analyses.Conclusion:Ā 1. Estradiol level in various bleeding pattern after 3,6,9,12 month of usage was not different. 2. There was correlation between low estradiol level and length of usage. 3. Association between bleeding pattern and estradiol level was not influenced by age, parity and body mass index, and total cholesterol level.Keywords: bleeding pattern, estradiol, DMPA, injectable contraceptio
Aktivitas Fisik dan Konsumsi Camilan pada Remaja Obesitas
Tujuan: Penelitian ini untuk mengetahui adanya perbedaan aktivitas fisik dan konsumsi camilan pada remaja obesitas di desa dan kota di Bantul.Metode: Penelitian ini menggunakan rancangan penelitian case control, dengan populasi remaja sekolah menengah atas (SMA) negeri di Kabupaten Bantul. Kasus adalah remaja yang didiagnosis obesitas pada tahap skrining, sedangkan kontrol adalah remaja dengan berat badan normal. Analisis data meliputi univariabel yang menyajikan distribusi frekuensi, bivariabel dengan uji chi-square dan uji-t dan mulitivariabel dengan uji regresi logistik.Hasil: Remaja dengan aktivitas fisik ringan memiliki peluang hampir 5 kali lebih besar mengalami obesitas dibandingkan remaja dengan aktivitas fisik sedang (OR 4,96 (CI 95%:2.14 -11.63). Hubungan antara jenis camilan dan obesitas juga memiliki hubungan yang bermakna secara statistik dan praktis, yaitu obesitas banyak di temukan sebanyak 2 kali lebih besar pada remaja dengan konsumsi camilan goreng dibandingkan dengan remaja yang mengkonsumsi camilan non goreng.Kesimpulan: Terdapat perbedaan rerata berat dan asupan camilan pada remaja obesitas dan non obesitas. Aktivitas fisik ringan, frekuensi camilan tinggi, jenis camilan gorengan, berat camilan dan asupan camilan tinggi berpeluang lebih besar meningkatkan obesitas remaja
The embryonic development and formation of Bunnei (Barbus sharpeyi Gunther, 1874)
Understanding the embryogenesis of Bunni is a useful tool for finding the time and suitable environmental conditions for spawning, growth requirements and use of techniques to increase the growth rate and survival. The stages of embryonic development for Bunnei (Barbus sharpeyi) was investigated in 22Ā°C. The reared brood stocks were spawned in captivity condition. The oocytes were spherical, brown and very adhesive. The cleavage was fast and the first division was recorded within 15-20 minutes after fertilization. The blastulation and gastrulation were investigated in 7:40 and 13:10 hours after fertilization with the yolk sac diameter of 1.18Ā±0.061mm (MeanĀ±SD), respectively. The organogenesis was started 21 hours after the fertilization, when the blastopore was closed and notochord was formed. The embryonic stages were continued by appearance the brain, the somites and the melanophores on the yolk sac. The heart was beaten and shown the blood circulation 65 hours after the fertilization. The head, tail and pectoral fins were moved frequently. The embryo reached to pre hatching and final hatching 79:10 and 84:10 hours after fertilization, respectively, and the embryo existed from corion with the length of about 5.29Ā±0/121mm (MeanĀ±SD)
Uji Validitas dan Reliabilitas Kwesioner Etiologi dan Faktor Risiko Kanker Nasofaring
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
Fixed-angle plates in patella fractures - a pilot cadaver study
<p>Abstract</p> <p>Objective</p> <p>Modified anterior tension wiring with K-wires and cannulated lag screws with anterior tension wiring are currently the fixation of choice for patellar fractures. Failure of fixation, migration of the wires, postoperative pain and resulting revision surgery, however, are not uncommon. After preliminary biomechanical testing of a new fixed-angle plate system especially designed for fixation of patella fractures the aim of this study was to evaluate the surgical and anatomical feasibility of implanting such a plate-device at the human patella.</p> <p>Methods</p> <p>In six fresh unfixed female cadavers without history of previous fractures around the knee (average age 88.8 years) a bilateral fixed-angle plate fixation of the patella was carried out after previous placement of a transverse central osteotomy. Operative time, intra-operative problems, degree of retropatellar arthritis (following Outerbridge), quality of reduction and existence of any intraarticular screw placement have been raised. In addition, lateral and anteroposterior radiographs of all specimens were made.</p> <p>Results</p> <p>Due to the high average age of 88.8 years no patella showed an unimpaired retropatellar articular surface and all were severely osteoporotic, which made a secure fixation of the reduction forceps during surgery difficult. The operation time averaged 49 minutes (range: 36-65). Although in postoperative X-rays the fracture gap between the fragments was still visible, the analysis of the retropatellar surface showed no residual articular step or dehiscence > 0.5 mm. Also in a total of 24 inserted screws not one intraarticular malposition was found. No intraoperative complications were noticed.</p> <p>Conclusions</p> <p>Osteosynthesis of a medial third patella fracture with a bilateral fixed-angle plate-device is surgically and anatomically feasible without difficulties. Further studies have to depict whether the bilateral fixed-angle plate-osteosynthesis of the patella displays advantages over the established operative procedures.</p
PUK30 Elicitation of Health-Related Quality of Life Concepts Associated with Overactive Bladder
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