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 $\chi$, 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 $\lambda=5\,$nm and relativistic amplitudes $a_0=10$-100, similarity scaling holds to a high degree, combined with $\chi\sim 1$ operation already at moderate $a_0\sim 50$, 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 $a_0$ leading to similar $\chi$.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 “Randomized Controlled Trial Planibu® and Depo Progestin®”Material 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

Simulation analysis of ultrasonic testing in steel-based butt weld joint

Within this study, a simulation analysis based on Ultrasonic Testing (UT) is made using Comsol Multiphysics. Comsol Multiphysics is a software that can simplify many aspects of building UT method and also can be used to obtain a fast understanding of the results of altering the fundamental parameters. The software program has useful features which can help in technique development especially for UT inspectors in Non- destructive Testing (NDT) field. The focus of this study is to conduct a simulation analysis of internal weld defects by developing the model of defects in a weld structure sample configured using the software. The model is developed based on actual parameters and characterization of weld structure sample and internal weld defects. The results of analysis show that each type of defects which are incomplete penetration, slag inclusion and lack of fusion have different signal pattern and signal amplitude which are depended on the characterizations of those defects themselves

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

Screening vaccine formulations for biological activity using fresh human whole blood.

Understanding the relevant biological activity of any pharmaceutical formulation destined for human use is crucial. For vaccine-based formulations, activity must reflect the expected immune response, while for non-vaccine therapeutic agents, such as monoclonal antibodies, a lack of immune response to the formulation is desired. During early formulation development, various biochemical and biophysical characteristics can be monitored in a high-throughput screening (HTS) format. However, it remains impractical and arguably unethical to screen samples in this way for immunological functionality in animal models. Furthermore, data for immunological functionality lag formulation design by months, making it cumbersome to relate back to formulations in real-time. It is also likely that animal testing may not accurately reflect the response in humans. For a more effective formulation screen, a human whole blood (hWB) approach can be used to assess immunological functionality. The functional activity relates directly to the human immune response to a complete formulation (adjuvant/antigen) and includes adjuvant response, antigen response, adjuvant-modulated antigen response, stability, and potentially safety. The following commentary discusses the hWB approach as a valuable new tool to de-risk manufacture, formulation design, and clinical progression