Modelling and thermal analysis of a seismic borehole sensor: diploma 2015

Analysis and adaptation of an acquisition system for a seismometer to enable operation at high temperatures (up to 180 [°C]). The simulation software and thermal measurements are used to validate theoretical results

Entropic insertion of a big sphere into a cylindrical vessel

We calculate the spatial distribution of the entropic potential between a big sphere and an even bigger vessel with cylindrical shape, which are immersed in small spheres, using the three-dimensional integral equation theory. The distribution is strongly dependent on relative magnitudes of the big-sphere diameter and the inner diameter of the vessel unless the latter is much larger than the former. For a fixed value of the inner diameter, a big sphere whose diameter lies in a specific range is spontaneously inserted into the vessel and strongly confined within a small space almost in the center of the vessel cavity

Capacity to make health care decisions: its importance in clinical practice

Background. Assessment of capacity plays a pivotal role in determining when decisions need to be made on behalf of an individual. It therefore has major clinical management implications for health care professionals and civil liberties implications for the person concerned. In many countries, there is a presumption that adults have the capacity to make health care decisions. However, in persons with a mental disability, capacity may be temporarily or permanently impaired. Methods. A selective review is presented which considers: (i) the broad approaches taken to determining capacity; (ii) the abilities commonly assessed in determining capacity; and (iii) the principles underlying health care decision-making for adults who are without capacity. Results. Capacity is a functional concept, determined by the person's ability to understand, retain, and weigh up information relevant to the decision in order to arrive at a choice, and then to communicate that choice. We have reviewed the studies that examined decision-making abilities in people with dementia, chronic mental illness or intellectual disabilities. Approaches to decision-making in adults who lack capacity include: anticipatory decisions made through advance health care statements or decisions by proxy based on ‘best interests’ or ‘substituted judgement’. Conclusions. The understanding of clinical and legal aspects of capacity is still developing. This paper examines current concepts of capacity and decision-making on behalf of those without capacity. We propose a framework, in line with current ethical and legal guidelines, as an aid to clinicians when they are seeking consent for a health care intervention.published_or_final_versio

Blinded assessment of treatment effects utilizing information about the randomization block length

It is essential for the integrity of double-blind clinical trials that during the study course the individual treatment allocations of the patients as well as the treatment effect remain unknown to any involved person. Recently, methods have been proposed for which it was claimed that they would allow reliable estimation of the treatment effect based on blinded data by using information about the block length of the randomization procedure. If this would hold true, it would be difficult to preserve blindness without taking further measures. The suggested procedures apply to continuous data. We investigate the properties of these methods thoroughly by repeated simulations per scenario. Furthermore, a method for blinded treatment effect estimation in case of binary data is proposed, and blinded tests for treatment group differences are developed both for continuous and binary data. We report results of comprehensive simulation studies that investigate the features of these procedures. It is shown that for sample sizes and treatment effects which are typical in clinical trials, no reliable inference can be made on the treatment group difference which is due to the bias and imprecision of the blinded estimates

The capacity of people with a ‘mental disability’ to make a health care decision

Background. Based on the developing clinical and legal literature, and using the framework adopted in draft legislation, capacity to make a valid decision about a clinically required blood test was investigated in three groups of people with a ‘mental disability’ (i.e. mental illness (chronic schizophrenia), ‘learning disability’ (‘mental retardation’, or intellectual or developmental disability), or, dementia) and a fourth, comparison group. Methods. The three ‘mental disability’ groups (N = 20 in the ‘learning disability’ group, N = 21 in each of the other two groups) were recruited through the relevant local clinical services; and through a phlebotomy clinic for the ‘general population’ comparison group (N = 20). The decision-making task was progressively simplified by presenting the relevant information as separate elements and modifying the assessment of capacity so that responding became gradually less dependent on expressive verbal ability. Results. Compared with the ‘general population’ group, capacity to make the particular decision was significantly more impaired in the ‘learning disability’ and ‘dementia’ groups. Importantly, however, it was not more impaired among the ‘mental illness’ group. All the groups benefited as the decision-making task was simplified, but at different stages. In each of the ‘mental disability’ groups, one participant benefited only when responding did not require any expensive verbal ability. Conclusions. Consistent with current views, capacity reflected an interaction between the decision-maker and the demands of the decision-making task. The findings have implications for the way in which decisions about health care interventions are sought from people with a ‘mental disability’. The methodology may be extended to assess capacity to make other legally-significant decisions.published_or_final_versio

UJI EFEKTIVITAS PESTISIDA NABATI EKSTRAK BAWANG PUTIH (Allium sativum) DAN BIJI MAHONI (Swietenia mahagoni) UNTUK MENURUNKAN POPULASI HAMA WERENG BATANG COKLAT (Nilaparvata lugens) PADA TANAMAN PADI

Jumlah penduduk Indonesia terus bertambah. Tahun 2014 jumlah penduduk Indonesia sebesar 252.034.314 jiwa, kebutuhan beras semakin meningkat (Departemen Pertanian RI, 2014). Berbagai upaya dilakukan untuk mendapatkan hasil produksi padi yang berlimpah. Namun serangan wereng batang coklat (Nilaparvata lugens) menurunkan produksi padi. Sekitar 27.000 hektar lahan padi di Jawa Timur mengalami puso, sedangkan 27 hektar tanaman padi siap panen di Lebak Banten dilaporkan gagal panen. Guna mencegah terjadinya gagal panen petani mengendalikan hama wereng batang coklat menggunakan pestisida kimia. Penggunaan pestisida kimia justru memberikan pengaruh buruk terhadap kualitas lingkungan, meningkatkan perkembangan populasi OPT, dan berpengaruh negatif terhadap kesehatan manusia. Pembelian pestisida kimia makin memberatkan biaya produksi bagi petani. Konsep pertanian terpadu berkelanjutan (sustainable agriculture) menghendaki adanya minimalisir input kimiawi ke lahan pertanian untuk menjaga keberlanjutan bagi usaha pertanian di masa mendatang. Melihat kondisi tersebut seharusnya diperlukan teknologi baru dalam mengendalikan hama wereng coklat. Kami menggagas penggunaan biopestisida berbahan baku alami yang ramah lingkungan dan mudah diusahakan oleh petani. Pestisida nabati yang terbuat dari bawang putih dan biji mahoni diduga dapat digunakan untuk mengendalikan hama WBC. Mahoni mengandung isoflavon yang berfungsi sebagai antifertilitas, penghambat makan, dan racun penghambat metabolisme. Bawang putih berfungsi sebagai penolak kehadiran (repelen) dan dapat merusak sistem saraf. Namun efektivitas dari pestisida nabati ini belum diketahui untuk mengendalikan hama WBC. Sehingga penelitian mengenai efektivitas pestisida nabati bawang putih dan biji buah mahoni perlu dilakukan. Penelitian dilaksanakan dengan menanam padi di pot-pot di rumah kasa. Beberapa pot padi diberikan pestisida nabati dari bawang putih dan biji mahoni, beberapa pot tidak diberikan pestisida sebagai kontrol, sedangkan sebagai pembanding beberapa pot diaplikasikan pestisida kimia REGENT 50WG. Pada usia 12 HST hama WBC dilepaskan ke dalam sungkup dan diamati apakah WBC menyerang tanaman padi

Chinese social media reaction to the MERS-CoV and avian influenza A(H7N9) outbreaks

BACKGROUND: As internet and social media use have skyrocketed, epidemiologists have begun to use online data such as Google query data and Twitter trends to track the activity levels of influenza and other infectious diseases. In China, Weibo is an extremely popular microblogging site that is equivalent to Twitter. Capitalizing on the wealth of public opinion data contained in posts on Weibo, this study used Weibo as a measure of the Chinese people's reactions to two different outbreaks: the 2012 Middle East Respiratory Syndrome Coronavirus (MERS-CoV) outbreak, and the 2013 outbreak of human infection of avian influenza A(H7N9) in China. METHODS: Keyword searches were performed in Weibo data collected by The University of Hong Kong's Weiboscope project. Baseline values were determined for each keyword and reaction values per million posts in the days after outbreak information was released to the public. RESULTS: The results show that the Chinese people reacted significantly to both outbreaks online, where their social media reaction was two orders of magnitude stronger to the H7N9 influenza outbreak that happened in China than the MERS-CoV outbreak that was far away from China. CONCLUSIONS: These results demonstrate that social media could be a useful measure of public awareness and reaction to disease outbreak information released by health authorities.published_or_final_versio