Preparation and characterization of hydroxyapatite (HA) from cow bone and its composite with poly (lactic acid) for bone replacement

The wide application of hydroxyapatite (HA) for medical applications such as bone tissue replacement sometimes constitutes environmental challenges as the conventional HA synthesis routes require the use of organic solvents. On the other hand, the current trend of research is to incorporate biomaterials such as HA into polymer matrices for some medical applications such as bone replacements. However, this often produces composites with inferior properties. This is due to poor HA dispersion within the composites as well as compatibility issues. In this study, natural HA was produced from cow bone through ultrasound and calcination processes at various temperatures. Composites then were produced from poly (lactic acid) (PLA) and hydroxyapatite (HA) through extrusion and injection molding. In order to foster good interaction between PLA and HA, and to impart antimicrobial properties onto the HA, surface of the HA was modified. On the other hand, impact properties of the PLA-HA composite was improved through the incorporation of impact modifier. Characterization of the produced HA was carried out through thermogravimetric (TGA) and field emission scanning electron microscope (FESEM) analysis. Spectrum obtained for the HA through Fourier Transform Infrared Spectroscopy was also compared with standard HA. Likewise, X-ray diffraction analysis of the HA in comparison with International Centre for Diffraction Data (ICDD) index for standard HA was conducted. On the other hand, Ca/P ratio of the produced HA was verified through Energy Dispersive X-ray analysis for elemental analysis. Likewise, different characterization techniques were used to characterize the composite produced. These include Fourier transforms infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA), tensile, flexural and impact analysis. Also microbial properties of the produced HA and its composite with PLA were assessed. In addition, in vitro biocompatibility study was used to assess the cell attachment and cell proliferation properties of the composites. Results showed that modification of HA led to increased HA dispersion within the PLA matrix, which resulted into significantly higher mechanical, thermal and dynamic mechanical properties of the resulting composite. Similarly, impact properties of the PLA-HA composite was remarkably improved after incorporation of biostrong impact modifier. In addition, in vitro study revealed that the PLA-HA composite exhibits good biocompatibility properties. In general, the results from this study shows that combination of the salient properties of HA with the good mechanical properties of PLA holds great potential for production of bone replacement composite materials with good load bearing ability. The composite produced herein can help to overcome the secondary operation procedures often associated with the conventional bone replacement procedures

Propidium monoazide (PMA) and ethidium bromide monoazide(EMA) improve DNA array and high-throughput sequencing ofporcine reproductive and respiratory syndrome virus identification

Pan-viral DNA array (PVDA) and high-throughput sequencing (HTS) are useful tools to identify novel viruses of emerging diseases. However, both techniques have difficulties to identify viruses in clinical samples because of the host genomic nucleic acid content (hg/cont). Both propidium monoazide (PMA) and ethidium bromide monoazide (EMA) have the capacity to bind free DNA/RNA, but are cell membrane-impermeable. Thus, both are unable to bind protected nucleic acid such as viral genomes within intact virions. However, EMA/PMA modified genetic material cannot be amplified by enzymes. In order to assess the potential of EMA/PMA to lower the presence of amplifiable hg/cont in samples and improve virus detection, serum and lung tissue homogenates were spiked with porcine reproductive and respiratory virus (PRRSV) and were processed with EMA/PMA. In addition, PRRSV RT-qPCR positive clinical samples were also tested. EMA/PMA treatments significantly decreased amplifiable hg/cont and significantly increased the number of PVDA positive probes and their signal intensity compared to untreated spiked lung samples. EMA/PMA treatments also increased the sensitivity of HTS by increasing the number of specific PRRSV reads and the PRRSV percentage of coverage. Interestingly, EMA/PMA treatments significantly increased the sensitivity of PVDA and HTS in two out of three clinical tissue samples. Thus, EMA/PMA treatments offer a new approach to lower the amplifiable hg/cont in clinical samples and increase the success of PVDA and HTS to identify viruses

PEMETAAN DAN PEMODELAN RIP CURRENT PADA KAWASAN WISATA PANTAI TELUK POPOH TULUNGAGUNG JAWA TIMUR

Wilayah pantai merupakan area yang biasa digunakan oleh para wisatawan untuk rekreasi. Namun, kasus kecelakaan pada wilayah pantai sendiri masih sangat tinggi yang mana salah satu faktor penyebabnya adalah rip current. Berdasarkan data dari Kantor Desa Besole, Kecamatan Besuki, Kabupaten Tulungagung, Jawa Timur bahwa terdapat 23 kasus korban terbawa arus dari tahun 2002 – 2012. Maka dari itu, diperlukan adanya observasi maupun prediksi terhadap kemunculan rip current pada Teluk Popoh. Penelitian ini bertujuan untuk menduga titik lokasi potensi kemunculan rip current; mengetahui karakteristik dan tipe rip current; dan mengetahui pengaruh parameter oseanografi terhadap potensi kemunculan rip current pada kawasan wisata Teluk Popoh. Data yang digunakan adalah data angin, gelombang, batimetri, pasang surut, kemiringan pantai, foto udara, dan citra satelit Digital Globe.  Penelitian dilakukan dari tanggal 19 Desember 2019 hingga 14 Februari 2020 yang terdiri dari survei lokasi; pengambilan data batimetri, pasang surut, dan foto udara di lapang; pengolahan data primer dan sekunder.  Identifikasi potensi kemunculan rip current dilakukan secara visual melalui citra satelit Digital Globe, foto udara dan pemodelan. Hasil penelitian menunjukkan bahwa terdapat beberapa lokasi indikasi kemunculan rip current jika diidentifikasi berdasarkan ciri – cirinya.  Selain itu, titik lokasi dan waktu kemunculan serta karakteristik dari rip current pada Teluk Popoh bervariasi tergantung pada faktor – faktor yang mempengaruhinya seperti perubahan musim, tinggi gelombang, kemiringan pantai, batimetri, keberadaan beach cusps, bentuk pantai, dan tipe pantai

Drawing Trees with Perfect Angular Resolution and Polynomial Area

We study methods for drawing trees with perfect angular resolution, i.e., with angles at each node v equal to 2{\pi}/d(v). We show: 1. Any unordered tree has a crossing-free straight-line drawing with perfect angular resolution and polynomial area. 2. There are ordered trees that require exponential area for any crossing-free straight-line drawing having perfect angular resolution. 3. Any ordered tree has a crossing-free Lombardi-style drawing (where each edge is represented by a circular arc) with perfect angular resolution and polynomial area. Thus, our results explore what is achievable with straight-line drawings and what more is achievable with Lombardi-style drawings, with respect to drawings of trees with perfect angular resolution.Comment: 30 pages, 17 figure

Quantifying the Diffusion of a Fluid through Membranes by RemoteDetection MRI

We present a method to measure self-diffusion acrossmembranes without the need for concentration or pressure gradients.Hyperpolarized xenon in combination with remote detection of NMR allowsthe measurement of membrane permeation, even in the gas phase. Theresulting images allow quantification of the amount of fluid diffusedthrough the membrane, and represent an alternative, potentially moreprecise way of measuring a membrane diffusion coefficient. The use ofremote detection of NMR allows for non-invasive signal encoding coupledto sensitive detection, making this approach ideal for the study ofdiffusion in intact devices such as fuel cells or separationsystems

Network and systems medicine: Position paper of the European Collaboration on Science and Technology action on Open Multiscale Systems Medicine

Introduction: Network and systems medicine has rapidly evolved over the past decade, thanks to computational and integrative tools, which stem in part from systems biology. However, major challenges and hurdles are still present regarding validation and translation into clinical application and decision making for precision medicine. Methods: In this context, the Collaboration on Science and Technology Action on Open Multiscale Systems Medicine (OpenMultiMed) reviewed the available advanced technologies for multidimensional data generation and integration in an open-science approach as well as key clinical applications of network and systems medicine and the main issues and opportunities for the future. Results: The development of multi-omic approaches as well as new digital tools provides a unique opportunity to explore complex biological systems and networks at different scales. Moreover, the application of findable, applicable, interoperable, and reusable principles and the adoption of standards increases data availability and sharing for multiscale integration and interpretation. These innovations have led to the first clinical applications of network and systems medicine, particularly in the field of personalized therapy and drug dosing. Enlarging network and systems medicine application would now imply to increase patient engagement and health care providers as well as to educate the novel generations of medical doctors and biomedical researchers to shift the current organ- and symptom-based medical concepts toward network- and systems-based ones for more precise diagnoses, interventions, and ideally prevention. Conclusion: In this dynamic setting, the health care system will also have to evolve, if not revolutionize, in terms of organization and management

Therapeutic approaches in the treatment of juvenile dermatomyositis in patients with recent-onset disease and in those experiencing disease flare: An international multicenter PRINTO study

Objective To evaluate response to therapy over a 24-month period in a large prospective international cohort of patients with juvenile dermatomyositis (DM). Methods The study included 145 patients with recent-onset juvenile DM and 130 juvenile DM patients experiencing disease flare, all of whom were \u3c18 years old. Disease activity parameters and therapeutic approaches in 4 geographic areas were analyzed at baseline and at 6, 12, and 24 months. Response was assessed according to the Pediatric Rheumatology International Trials Organization (PRINTO) juvenile DM response criteria, and data were reported as observed and in the intent-to-treat (ITT) population. Results Patients with recent-onset juvenile DM at baseline had higher baseline disease activity and greater improvement over 24 months when compared to juvenile DM patients experiencing disease flare at baseline. Methotrexate (MTX) or high-dose corticosteroids were administered more frequently to patients with recent-onset juvenile DM, compared to juvenile DM patients experiencing disease flare, who were more likely to receive cyclosporine. Compared to patients from Western and Eastern Europe, a higher proportion of patients from South and Central America and North America received pulse steroids, and the average steroid dosage was higher in the North American and South and Central American patients. The use of MTX was similar in all 4 regions, while cyclosporin A was more frequently used in Western Europe. In the as observed analysis, 57.9% of the patients with recent-onset juvenile DM and 36.4% of the patients experiencing disease flare (P \u3c 0.001) reached at least a 70% response by PRINTO criteria at 6 months; these proportions had increased at month 24 to 78.4% and 51.2%, respectively (P \u3c 0.001). Corresponding results of the ITT analysis were much lower, with only one-third of the patients able to maintain the initial assigned therapy over 24 months. Conclusion Patients with recent-onset juvenile DM are more likely to achieve significant clinical improvement over 24 months, when compared to patients experiencing flares of juvenile DM. Internationally, various therapeutic approaches are used to treat this disease. Copyright © 2011 by the American College of Rheumatology

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Study on Occupational Allergy Risks (SOLAR II) in Germany: Design and methods

<p>Abstract</p> <p>Background</p> <p>SOLAR II is the 2^ndfollow-up of a population-based cohort study that follows the participants of ISAAC Phase Two recruited in Munich and Dresden in 1995/6. A first follow-up study was conducted 2002 and 2003 (SOLAR I). The aims of SOLAR II were to investigate the course of atopic diseases over puberty taking environmental and occupational risk factors into account. This paper describes the methods of the 2^ndfollow-up carried out from 2007 to 2009 and the challenges we faced while studying a population-based cohort of young adults.</p> <p>Methods</p> <p>Wherever possible, the same questionnaire instruments were used throughout the studies. They included questions on respiratory and allergic diseases, domestic and occupational exposure and work related stress. Furthermore, clinical examinations including skin prick tests, spirometry and bronchial challenge with methacholine, exhaled nitric oxide (FeNO) and blood samples were employed at baseline and 2^ndfollow-up. As information from three studies was available, multiple imputation could be used to handle missing data.</p> <p>Results</p> <p>Of the 3053 SOLAR I study participants who had agreed to be contacted again, about 50% had moved in the meantime and had to be traced using phone directories and the German population registries. Overall, 2904 of these participants could be contacted on average five years after the first follow-up. From this group, 2051 subjects (71%) completed the questionnaire they received via mail. Of these, 57% participated at least in some parts of the clinical examinations. Challenges faced included the high mobility of this age group. Time constraints and limited interest in the study were substantial. Analysing the results, selection bias had to be considered as questionnaire responders (54%) and those participating in the clinical part of the study (63%) were more likely to have a high parental level of education compared to non-participants (42%). Similarly, a higher prevalence of parental atopy (e.g. allergic rhinitis) at baseline was found for participants in the questionnaire part (22%) and those participating in the clinical part of the study (27%) compared to non-participants (11%).</p> <p>Conclusions</p> <p>In conclusion, a 12-year follow-up from childhood to adulthood is feasible resulting in a response of 32% of the baseline population. However, our experience shows that researchers need to allocate more time to the field work when studying young adults compared to other populations.</p