Pengaruh Arus Sepanjang Pantai (Longshore Current) terhadap Sebaran Sedimen Dasar di Perairan Teluk Awur, Jepara

Mekanisme berpindahnya sedimen dari satu tempat ke tempat yang lain sangat dipengaruhi oleh longshore current(arus sepanjang pantai), hal ini menyebabkan terjadinya abrasidiwilayah Perairan Teluk Awur akibat penjalaran gelombang yang dibangkitkan oleh angin (gelombang permukaan). Tujuan dilakukannya penelitian ini untuk mengetahui pengaruh dari arus sepanjang pantai terhadap angkutan sedimen dasar yang ada di Perairan Teluk Awur, Jepara. Penelitian ini dilaksanakan tanggal 2-5 Maret 2015 di Perairan Teluk Awur, Jepara. Metode yang digunakan dalam penelitian ini adalah kuantitaif. Peramalan gelombang laut menggunakan metode SMB (Sverdrup Munk Bretchneider) dengan inputan data angin, sedangkan untuk menentukan transport sedimen menggunakan rumus empiris yang didapat dari pengaruh gelombang.Hasil penelitian di Teluk Awur menunjukkan tinggi gelombang pecah ( ) berkisar antara 0,4 – 1,5 meter dengan kedalaman gelombang pecah berkisar antara ( ) 0,5 – 1,8 meter. Arus sepanjang pantai kecepatannya berkisar antara 0,7 – 2,0 m/s dengan arah cenderung menuju utara, karena gelombang dominan datang dari arah barat dan bentuk dari daratan Teluk Awur. Dominasi jenis sedimen di Teluk Awur berupa pasir dan gravely sand, dengan potensi angkutan sedimen berkisar 65,3 – 2.176 m³/hari atau 23.824 – 794.547 m³/tahun

Mortality of emergency abdominal surgery in high-, middle- and low-income countries

Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)

An Analysis on Vulnerabilities of Password Retrying

Recently, due to security concerns, most of the computing systems have employed authentication based access control mechanisms. Again, in general, a considerable number of such systems we use in our day-to-day life. Hence, we also have to memorize a considerably large number of passwords, which incurs the issue of memorability. Mostly, a user retries password due to memorability problem. However, password retrying leads to several vulnerabilities. The main objective of this paper is to unveil these vulnerabilities with appropriate evidences. In this process, we discover and report an attack, named retry attack, which is discussed elaborately. An experiment has been performed and a survey has been conducted to examine the impact of such attack on 27 participants—where the experiment has been designed in such a way that it does not violate the ethical regulations of the university and preserves the secrecy of the participants’ passwords. The results evidently demonstrate the impact of such attack. At the end, some suggestions are noted that would assist a user to tackle this kind of attack

Dimension stability, tensile and thermomechanical properties of bamboo/oil palm fibre reinforced bio-epoxy hybrid biocomposites

The rising liability to suffer the environment eco-friendly covers the approach to the improvement of materials with bio-natural wastes. This research experimentally aims to study bamboo/oil palm reinforced bio-epoxy hybrid composite. Bamboo (B) and oil palm (O) reinforced bio-epoxy was fabricated as a control. The fabricated biocomposites were characterised by mechanical properties (tensile tests), physical characterisations (density, water absorption (WA) and thickness swelling (TS)), thermomechanical analysis (TMA), and morphological (scanning electron microscopy (SEM)). Among the hybrid composites, 5B5O has the highest tensile strength and modulus which is 35.66 MPa and 4.95 GPa, respectively. Based on the findings, the physical properties, WA and TS capacities (WA and TS) of B and 3B7O biocomposites were increased compared with all corresponding biocomposites while the O biocomposite exhibited lower TS and WA values compared to other samples. The hybrid 3B7O biocomposite sample was attributed to a higher void percentage (6.29%) and lower density (1.25 g/cm3) compared to other biocomposites. Generally, the SEM analysis of hybrid biocomposites confirms a valuable interaction between the filler and the matrix as further penetration for the matrix was permitted into the greatly porous structures of natural fibres. Furthermore, the SEM test of the fracture point confirmed the observations from the mechanical properties. The obtained findings confirmed that hybrid fibres improve the properties of the bio-epoxy matrix and can be utilised as sustainable and renewable biocomposites for several applications such as automotive tools, furniture and medical tools

Effect of curing temperature on mechanical properties of bio-phenolic/epoxy polymer blends

Nowadays, researchers continue studies for alternative materials to replace the redundant petroleum-based products. The combination of various polymer mixture process mainly from bio-polymer material as a matrix property could reduce the dependence over petroleum-based polymer, thus the dangerous residue waste from the synthetic polymer in the fabrication process could be eliminated and produce better composite material with lower cost and high performance of composite material in numerous applications. In this study, the effect of bio-phenolic loading and curing temperature on the mechanical properties of bio-phenolic/epoxy polymer blends was investigated. Bio-phenolic/epoxy polymer blends were fabricated with different loading of bio-phenolic resin (5(P-5), 10(P-10), 15(P-15), 20(P-20) and 25(P-25) wt%) and different curing temperature was used which is 100 °C, 130 °C and 150 °C. The overall mechanical properties of bio-phenolic/epoxy polymer blends were improved as bio-phenolic loading increase and curing temperature increase. Obtained results indicated that bio-phenolic/epoxy polymer blends with 20 wt% bio-phenolic at 150 °C showed the highest tensile strength, flexural strength and impact resistance whereas highest tensile modulus and flexural modulus was shown by polymer blend with 25 wt% bio-phenolic at 100 °C and 25wt% bio-phenolic at 130 °C, respectively. It can be concluded that polymer blend with 20wt% bio-phenolic at 150 °C showed overall good mechanical properties. On the basis of finding obtained in this work will be used for further study to fabricate flax fiber/carbon-kevlar reinforced in optimum polymer blends for ballistic helmet applications

The Advancement of Solid-State Transformer Technology and Its Operation and Control with Power Grids: A Review

Solid-state transformer (SST) technology is one of the developing technologies that will be widely used in the future to integrate low-voltage and high-voltage networks with control circuitries and power electronics converters, facilitating renewables integration in smart grid applications. SST technology has crucial key advantageous features, including compact size and weight, low cost, and ease of connection in offshore applications. However, SST technology exhibits a few concerns, such as implementation, protection, economic, and communication compatibility, that need to be addressed. This paper aims to review SST technology with its advanced control schemes and provide future directions for research and development, applications, and prospects. In line with this, highly cited SST technology papers are examined to derive and summarize concerning issues related to its operation and control with further research development of power grids. Moreover, this review discusses the assessment and state-of-the-art technology of SSTs in different applications, focusing on configurations, control circuitry, and their drawbacks and benefits. Numerous issues and challenges of SST technology are explored to identify the existing knowledge gaps and potential future recommendations. All these critical analyses, information, and evaluations would benefit power engineers and researchers in developing and implementing advanced intelligent SST technologies for sustainable energy management in future power systems

30-Day morbidity and mortality of bariatric metabolic surgery in adolescence during the COVID-19 pandemic – The GENEVA study

Background: Metabolic and bariatric surgery (MBS) is an effective treatment for adolescents with severe obesity. Objectives: This study examined the safety of MBS in adolescents during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This was a global, multicentre and observational cohort study of MBS performed between May 01, 2020, and October 10,2020, in 68 centres from 24 countries. Data collection included in-hospital and 30-day COVID-19 and surgery-specific morbidity/mortality. Results: One hundred and seventy adolescent patients (mean age: 17.75 ± 1.30 years), mostly females (n&nbsp;=&nbsp;122, 71.8%), underwent MBS during the study period. The mean pre-operative weight and body mass index were 122.16 ± 15.92 kg and 43.7&nbsp;± 7.11 kg/m2, respectively. Although majority of patients had pre-operative testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (n&nbsp;=&nbsp;146; 85.9%), only 42.4% (n&nbsp;=&nbsp;72) of the patients were asked to self-isolate pre-operatively. Two patients developed symptomatic SARS-CoV-2 infection post-operatively (1.2%). The overall complication rate was 5.3% (n&nbsp;=&nbsp;9). There was no mortality in this cohort. Conclusions: MBS in adolescents with obesity is safe during the COVID-19 pandemic when performed within the context of local precautionary procedures (such as pre-operative testing). The 30-day morbidity rates were similar to those reported pre-pandemic. These data will help facilitate the safe re-introduction of MBS services for this group of patients

30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries.

BACKGROUND There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2019 (COVID-19) pandemic and to determine the efficacy of perioperative COVID-19 protective strategies on postoperative symptomatic COVID-19 rates. METHODS We conducted an international cohort study to determine all-cause and COVID-19-specific 30-day morbidity and mortality of BS performed between 01/05/2020 and 31/10/2020. RESULTS Four hundred ninety-nine surgeons from 185 centres in 42 countries provided data on 7704 patients. Elective primary BS (n = 7084) was associated with a 30-day morbidity of 6.76% (n = 479) and a 30-day mortality of 0.14% (n = 10). Emergency BS, revisional BS, insulin-treated type 2 diabetes, and untreated obstructive sleep apnoea were associated with increased complications on multivariable analysis. Forty-three patients developed symptomatic COVID-19 postoperatively, with a higher risk in non-whites. Preoperative self-isolation, preoperative testing for SARS-CoV-2, and surgery in institutions not concurrently treating COVID-19 patients did not reduce the incidence of postoperative COVID-19. Postoperative symptomatic COVID-19 was more likely if the surgery was performed during a COVID-19 peak in that country. CONCLUSIONS BS can be performed safely during the COVID-19 pandemic with appropriate perioperative protocols. There was no relationship between preoperative testing for COVID-19 and self-isolation with symptomatic postoperative COVID-19. The risk of postoperative COVID-19 risk was greater in non-whites or if BS was performed during a local peak

Safety of Bariatric Surgery in ≥ 65-Year-Old Patients During the COVID-19 Pandemic

Background Age &gt;= 65 years is regarded as a relative contraindication for bariatric surgery. Advanced age is also a recognised risk factor for adverse outcomes with Coronavirus Disease-2019 (COVID-19) which continues to wreak havoc on global populations. This study aimed to assess the safety of bariatric surgery (BS) in this particular age group during the COVID-19 pandemic in comparison with the younger cohort.Methods We conducted a prospective international study of patients who underwent BS between 1/05/2020 and 31/10/2020. Patients were divided into two groups - patients &gt;= 65-years-old (Group I) and patients &lt; 65-years-old (Group II). The two groups were compared for 30-day morbidity and mortality.Results There were 149 patients in Group 1 and 6923 patients in Group II. The mean age, preoperative weight, and BMI were 67.6 +/- 2.5 years, 119.5 +/- 24.5 kg, and 43 +/- 7 in Group I and 39.8 +/- 11.3 years, 117.7 +/- 20.4 kg, and 43.7 +/- 7 in Group II, respectively. Approximately, 95% of patients in Group 1 had at least one co-morbidity compared to 68% of patients in Group 2 (p = &lt; 0.001). The 30-day morbidity was significantly higher in Group I ( 11.4%) compared to Group II (6.6%) (p = 0.022). However, the 30-day mortality and COVID-19 infection rates were not significantly different between the two groups.Conclusions Bariatric surgery during the COVID-19 pandemic is associated with a higher complication rate in those &gt;= 65 years of age compared to those &lt; 65 years old. However, the mortality and postoperative COVID-19 infection rates are not significantly different between the two groups

Effect of BMI on safety of bariatric surgery during the COVID-19 pandemic, procedure choice, and safety protocols - An analysis from the GENEVA Study

Background: It has been suggested that patients with a Body Mass Index (BMI) of &gt; 60 kg/m2 should be offered expedited Bariatric Surgery (BS) during the Coronavirus Disease-2019 (COVID-19) pandemic. The main objective of this study was to assess the safety of this approach. Methods: We conducted a global study of patients who underwent BS between 1/05/2020 and 31/10/2020. Patients were divided into three groups according to their preoperative BMI -Group I (BMI &lt; 50 kg/m2), Group II (BMI 50-60 kg/m2), and Group III (BMI &gt; 60 kg/m2). The effect of preoperative BMI on 30-day morbidity and mortality, procedure choice, COVID-19 specific safety protocols, and comorbidities was assessed. Results: This study included 7084 patients (5197;73.4 % females). The mean preoperative weight and BMI were 119.49 &amp; PLUSMN; 24.4 Kgs and 43.03 &amp; PLUSMN; 6.9 Kg/m2, respectively. Group I included 6024 (85 %) patients, whereas Groups II and III included 905 (13 %) and 155 (2 %) patients, respectively.The 30-day mortality rate was higher in Group III (p = 0.001). The complication rate and COVID-19 infection were not different. Comorbidities were significantly more likely in Group III (p = &lt; 0.001). A significantly higher proportion of patients in group III received Sleeve Gastrectomy or One Anastomosis Gastric Bypass compared to other groups. Patients with a BMI of &gt; 70 kg/m2 had a 30-day mortality of 7.7 % (2/26). None of these patients underwent a Roux-en-Y Gastric Bypass. Conclusion: The 30-day mortality rate was significantly higher in patients with BMI &gt; 60 kg/m2. There was, however, no significant difference in complications rates in different BMI groups, probably due to differences in procedure selection