ANALISIS SISTEM THERMAL PADA DOUBLE DRUM CROSS SECTION WATER TUBE BOILER UNTUK MEMPRODUKSI SUPERHEATED STEAM BERDASARKAN PENGARUH RASIO UDARA BAHAN BAKAR SOLAR

Water Tube Boiler adalah alat yang dibuat untuk menghasilkan uap air, Produksi uap dalam ketel uap dihasilkan dari pemanasan air menjadi uap dan karena uapnya dipampat dan menjadi bertekanan dan mempunyai panas yang suhunya tinggi. Proses pengapian yang terjadi di luar pipa yang kemudian panas tersebut memanaskan pipa yang berisi air yang sebelumnya sudah dikondisikan melalui economizer. Steam yang dihasilkan kemudian dikumpulkan pada wadah yang disebut steamdrum. Tekanan atau panas ini dipergunakan orang untuk pemanas dan memasak, pengering, dan pembangkit energi. Kualitas steam boiler dipengaruhi oleh desain awal boiler, kualitas air umpan, aliran uap, Tekanan Boiler, Temperatur, Efisiensi Boiler. Untuk mendapatkan kualitas steam yang baik dipengaruhi dengan kondisi input bahan bakar dan udara pada proses pembakaran. Dimana bahan bakar yang digunakan harus mempunyai nilai kalor lebih besar agar kemampuan udara bercampur dengan bahan bakar akan lebih baik. Perbandingan udara bahan bakar dalam penelitian mengenai boiler dengan menggunakan sistem Double Drum Water Tube Boiler dilakukan pengamatan dengan pengaruh rasio udara divariasikan untuk melihat kualitas dari steam yang dihasilkan. Dengan rasio yang digunakan 6,10 ; 9,16 ; 11,35 ; 17,57; dan 18,16 dan Flow bahan bakar 4,98 kg/jam. Tujuannya untuk mengetahui pengaruh rasio udara bahan bakar mempengaruhi kualitas steam yang dihasilkan

Fin whales of the Great Bear Rainforest : Balaenoptera physalus velifera in a Canadian Pacific fjord system

Funding: This research was supported by a Mitacs Accelerate Internship (IT21479); the Save Our Seas Foundation; Willow Grove Foundation; Donner Canadian Foundation; Tides Canada; LUSH Charity Pot; private donations to North Coast Cetacean Society; Fisheries and Oceans Canada; and the Canada Nature Fund for Aquatic Species at Risk (CANAFSAR 2019-2021).Fin whales (Balaenoptera physalus) are widely considered an offshore and oceanic species, but certain populations also use coastal areas and semi-enclosed seas. Based upon fifteen years of study, we report that Canadian Pacific fin whales (B. p. velifera) have returned to the Kitimat Fjord System (KFS) in the Great Bear Rainforest, and have established a seasonally resident population in its intracoastal waters. This is the only fjord system along this coast or elsewhere in which fin whales are known to occur regularly with strong site fidelity. The KFS was also the only Canadian Pacific fjord system in which fin whales were commonly found and killed during commercial whaling, pointing to its long-term importance. Traditional knowledge, whaling records, and citizen science databases suggest that fin whales were extirpated from this area prior to their return in 2005-2006. Visual surveys and mark-recapture analysis documented their repopulation of the area, with 100-120 whales using the fjord system in recent years, as well as the establishment of a seasonally resident population with annual return rates higher than 70%. Line transect surveys identified the central and outer channels of the KFS as the primary fin whale habitat, with the greatest densities occurring in Squally Channel and Caamano Sound. Fin whales were observed in the KFS in most months of the year. Vessel- and shore-based surveys (27,311 km and 6,572 hours of effort, respectively) indicated regular fin whale presence (2,542 detections), including mother-calf pairs, from June to October and peak abundance in late August-early September. Seasonal patterns were variable year-to-year, and several lines of evidence indicated that fin whales arrived and departed from the KFS repeatedly throughout the summer and fall. Additionally, we report on the population's social network and morphometrics. These findings offer insights into the dynamics of population recovery in an area where several marine shipping projects are proposed. The fin whales of the Great Bear Rainforest represent a rare exception to general patterns in this species' natural history, and we highlight the importance of their conservation.Publisher PDFPeer reviewe

Cardiac toxicity of trastuzumab in metastatic breast cancer patients previously treated with high-dose chemotherapy: a retrospective study

HER-2 overexpression is associated to a poor prognosis in high-risk and metastatic breast cancer (MBC) patients treated with high-dose chemotherapy (HDC). HER-2 status is also a predictive factor and when trastuzumab is administered in combination with or sequentially to chemotherapy, a significant disease-free and/or overall survival improvement has been observed in HER-2+ early and MBC. Unfortunately, in both settings, trastuzumab is associated with an increased risk of cardiac dysfunction (CD). We have reviewed the clinical charts of HER-2-overexpressing MBC patients treated with trastuzumab after HDC. Age, baseline left ventricular ejection fraction (LVEF), radiation therapy on cardiac area, exposure to anthracycline, single or multiple transplant, high-dose agents, trastuzumab treatment duration were recorded as potential risk factors. In total, 53 patients have been included in the analysis. Median LVEF at baseline was 60.5%; at the end of trastuzumab (data available for 28 patients only), it was 55% (P=0.01). Five out of the 28 (17.9%) patients experienced CD. Two out of 53 (3.8%) patients developed a congestive heart failure. Age ⩾50 years and multiple transplant procedure were potential risk factors for CD. The overall incidence of CD observed in this population of HER-2+ MBC patients treated with trastuzumab after HDC is not superior to that reported with concomitant trastuzumab and anthracyclines. However, patients with age ⩾50 years or receiving multiple course of HDC should be considered at risk for CD

Cumulative impact mapping: advances, relevance and limitations to marine management and conservation, using Canada’s Pacific waters as a case study

Analysis of cumulative human impacts in the marine environment is still in its infancy but developing rapidly. In this study, existing approaches were expanded upon, aiming for a realistic consideration of cumulative impacts at a regional scale. Thirty-eight human activities were considered, with each broken down according to stressor types and a range of spatial influences. To add to the policy relevance, existing stressors within and outside of conservation areas were compared. Results indicate the entire continental shelf of Canada's Pacific marine waters is affected by multiple human activities at some level. Commercial fishing, land-based activities and marine transportation accounted for 57.0%, 19.1%, and 17.7% of total cumulative impacts, respectively. Surprisingly, most areas with conservation designations contained higher impact scores than the mean values of their corresponding ecoregions. Despite recent advances in mapping cumulative impacts, many limitations remain. Nonetheless, preliminary analyses such as these can provide information relevant to precautionary management and conservation efforts