45 research outputs found
The Effects of Tropospheric Bias on Deformation Monitoring of MT. Guntur using GPS Survey Method
Pemantauan deformasi gunung api yang andal menuntut ketelitian yang tinggi, yaitu sampai level keteliatian mm untuk kasus gunung api yang tengah 'bangkit' kembali. Konsekuensinya adalah kesalahan dan bias yang dapat mengurangi ketelitian dalam penentuan posisi dengan satelit GPS harus dieliminasi dana tau direduksi, seperti kesalahan yang disebabkan oleh bias troposfer. Pada kasus pemantauan deformasi gunung api dengan metode survei GPS, karena adanya perbedaan tinggi yang cukup besar dan variatif antara titik-titik dalam jaringan, maka efek kesalahan bias troposfer tidak sepenuhnya dapat direduksi dengan proses pengurangan data (differencing). Residu (sisa) bias troposter ini harus dikoreksi agar tingkat keteliatian yang dituntut oleh sistem pemantauan deformasi gunung api dapat tetap tercapai. Pada makalah ini akan dibahas efek bias troposfer pada pemantauan deformasi gunung api. Pembahasan didasarkan pada hasil yang diperoleh dari pemantauan deformasi G. Guntur (Garut, Jawa Barat) dengan metode survei GPS. The Effects of Tropospheric Bias on Deformation Monitoring of MT. Guntur using GPS Survey MethodA reliable volcano deformation monitoring requires a high positioning accuracy, i.e. up to mm level in the case of reawakening volcanoes. As a consequence of this requirement, the errors and biases affecting the GPS positioning accuracy has to be eliminated or reduced, which one of them is the tropospheric bias. In the case of volcano deformation monitoring using the GPS survey method, due to a relatively large altitude variation in the stations altitude, the effects of tropospheric bias could not be effectively reduced by the differencing process. In order to meet the accuracy requirement of volcano deformation monitoring system, this residual tropospheric bias, therefore, has to be somehow corrected or taken into account. In this paper, the effects of tropospheric bias on the volcano deformation monitoring will be discussed. The discussion is based on the results from the deformation monitoring of Guntur volcano in Garut, West Java, by using repeated GPS surveys
Effect Of Functional Endoscopic Sinus Surgery To The Flow Behavior In Nasal During Resting Breathing Condition
Functional endoscopic sinus surgery (FESS) is a surgery to removeuncinate process in order to restore sufficient sinus ventilation and drainagein nasal. However, there were a few cases with side effects such as facialpain, reduction in sense of smell and sinusitis reoccurrence of infection. Inthis study, the effect of uncinate process removal is investigated. Images ofthe model were done through computational technique and then the flowwas simulated to predict the effect of the removal. Inhalation processes withresting breathing condition were modeled. The results show that smoothflow was observed at nasal area which indicates successful surgical process.However for post FESS model the result shows that the possibilities ofsinusitis reoccurrence of infection were high. Finally, velocity profile in theolfactory area show non-favorable flow condition for effective smell senses
Polymer-based or polymer-free stents in patients at high bleeding risk
Background: polymer-free drug-coated stents provide superior clinical outcomes to bare-metal stents in patients at high bleeding risk who undergo percutaneous coronary intervention (PCI) and are treated with 1 month of dual antiplatelet therapy. Data on the use of polymer-based drug-eluting stents, as compared with polymer-free drug-coated stents, in such patients are limited. Methods: in an international, randomized, single-blind trial, we compared polymer-based zotarolimus-eluting stents with polymer-free umirolimus-coated stents in patients at high bleeding risk. After PCI, patients were treated with 1 month of dual antiplatelet therapy, followed by single antiplatelet therapy. The primary outcome was a safety composite of death from cardiac causes, myocardial infarction, or stent thrombosis at 1 year. The principal secondary outcome was target-lesion failure, an effectiveness composite of death from cardiac causes, target-vessel myocardial infarction, or clinically indicated target-lesion revascularization. Both outcomes were powered for noninferiority. Results: a total of 1996 patients at high bleeding risk were randomly assigned in a 1:1 ratio to receive zotarolimus-eluting stents (1003 patients) or polymer-free drug-coated stents (993 patients). At 1 year, the primary outcome was observed in 169 of 988 patients (17.1%) in the zotarolimus-eluting stent group and in 164 of 969 (16.9%) in the polymer-free drug-coated stent group (risk difference, 0.2 percentage points; upper boundary of the one-sided 97.5% confidence interval [CI], 3.5; noninferiority margin, 4.1; P = 0.01 for noninferiority). The principal secondary outcome was observed in 174 patients (17.6%) in the zotarolimus-eluting stent group and in 169 (17.4%) in the polymer-free drug-coated stent group (risk difference, 0.2 percentage points; upper boundary of the one-sided 97.5% CI, 3.5; noninferiority margin, 4.4; P = 0.007 for noninferiority). Conclusions: among patients at high bleeding risk who received 1 month of dual antiplatelet therapy after PCI, use of polymer-based zotarolimus-eluting stents was noninferior to use of polymer-free drug-coated stents with regard to safety and effectiveness composite outcomes. (Funded by Medtronic; ONYX ONE ClinicalTrials.gov number, NCT03344653.)
Developing a framework for evaluation: a Theory of Change for complex workplace mental health interventions
Background There is a gap between the necessity of effective mental health interventions in the workplace and the availability of evidence-based information on how to evaluate them. The available evidence outlines that mental health interventions should follow integrated approaches combining multiple components related to different levels of change. However, there is a lack of robust studies on how to evaluate multicomponent workplace interventions which target a variety of outcomes at different levels taking into account the influence of different implementation contexts. Method We use the MENTUPP project as a research context to develop a theory-driven approach to facilitate the evaluation of complex mental health interventions in occupational settings and to provide a comprehensive rationale of how these types of interventions are expected to achieve change. We used a participatory approach to develop a ToC involving a large number of the project team representing multiple academic backgrounds exploiting in tandem the knowledge from six systematic reviews and results from a survey among practitioners and academic experts in the field of mental health in SMEs. Results The ToC revealed four long-term outcomes that we assume MENTUPP can achieve in the workplace: 1) improved mental wellbeing and reduced burnout, 2) reduced mental illness, 3) reduced mental illness-related stigma, and 4) reduced productivity losses. They are assumed to be reached through six proximate and four intermediate outcomes according to a specific chronological order. The intervention consists of 23 components that were chosen based on specific rationales to achieve change on four levels (employee, team, leader, and organization). Conclusions The ToC map provides a theory of how MENTUPP is expected to achieve its anticipated long-term outcomes through intermediate and proximate outcomes assessing alongside contextual factors which will facilitate the testing of hypotheses. Moreover, it allows for a structured approach to informing the future selection of outcomes and related evaluation measures in either subsequent iterations of complex interventions or other similarly structured programs. Hence, the resulting ToC can be employed by future research as an example for the development of a theoretical framework to evaluate complex mental health interventions in the workplace
Postoperative complications after pancreatoduodenectomy for malignancy: results from the Recurrence After Whipple’s (RAW) study
Background
Pancreatoduodenectomy (PD) is associated with significant postoperative morbidity. Surgeons should have a sound understanding of the potential complications for consenting and benchmarking purposes. Furthermore, preoperative identification of high-risk patients can guide patient selection and potentially allow for targeted prehabilitation and/or individualized treatment regimens. Using a large multicentre cohort, this study aimed to calculate the incidence of all PD complications and identify risk factors.
Method
Data were extracted from the Recurrence After Whipple’s (RAW) study, a retrospective cohort study of PD outcomes (29 centres from 8 countries, 2012–2015). The incidence and severity of all complications was recorded and potential risk factors for morbidity, major morbidity (Clavien–Dindo grade > IIIa), postoperative pancreatic fistula (POPF), post-pancreatectomy haemorrhage (PPH) and 90-day mortality were investigated.
Results
Among the 1348 included patients, overall morbidity, major morbidity, POPF, PPH and perioperative death affected 53 per cent (n = 720), 17 per cent (n = 228), 8 per cent (n = 108), 6 per cent (n = 84) and 4 per cent (n = 53), respectively. Following multivariable tests, a high BMI (P = 0.007), an ASA grade > II (P II patients were at increased risk of major morbidity (P < 0.0001), and a raised BMI correlated with a greater risk of POPF (P = 0.001).
Conclusion
In this multicentre study of PD outcomes, an ASA grade > II was a risk factor for major morbidity and a high BMI was a risk factor for POPF. Patients who are preoperatively identified to be high risk may benefit from targeted prehabilitation or individualized treatment regimens
Numerical simulation of plate-fin recuperator
The aim of this study is to investigate the effect of geometrical variations on the performance of plate-fin recuperator. Solutions for this problem are obtained via numerical approach. Three different types of plate-fin recuperator has been investigated; rectangular, rounded and bullet edges. This study has shown that rounded and bullet edges plate fin configuration exhibits 28 percent increase in surface heat transfer coefficient over its rectangular counterpart but there is no significant difference in the Fanning friction factor