Pengaruh Pemanasan Bahan Bakar dengan Radiator sebagai Upaya Meningkatkan Kinerja Mesin Bensin

Proses pembakaran bahan bakar di dalam silinder dipengaruhi oleh: temperatur, kerapatan campuran, komposisi, dan turbulensi yang ada pada campuran. Apabila temperatur campuran bahan bakar dengan udara naik, maka semakin mudah campuran bahan bakar dengan udara tersebut untuk terbakar. Tujuan penelitian ini adalah untuk mengetahui pengaruh pemanasan bahan bakar dengan media radiator terhadap konsumsi bahan bakar dan kinerja Motor bakar bensin jenis daihatsu hijet 1000. Metode penelitian menggunakan metode eksperimen. Variabel bebasnya adalah putaran mesin dan jenis bahan bakar yaitu premium dan variabel Terikat adalah konsumsi bahan bakar dan daya mesin. Hasil penelitian menunjukkan, bahan bakar yang telah dipanaskan lewat radiator mempunyai keuntungan yaitu menghemat bahan bakar, sebelum dipanaskan sebesar 42 ml/s setelah dipanaskan menjadi 25.8 ml/s pada putaran 2000 rpm. daya efektif yang dihasilkan juga meningkat,sebelum dipanaskan sebesar 18.521 kg/cm² setelah dipanaskan sebesar 20.949 kg/cm² pada putaran 2500 rpm

A Study on Biological Parameters of Aquaculture Area in Bahoi Village Northern Minahasa Regency, North Sulawesi

Tujuan penelitian ini adalah untuk mengetahui parameter biologi dan mengidentifikasi jenis-jenis plankton serta menganalisis kepadatan dan keanekaragaman plankton di lokasi budidaya Desa Bahoi. Sampel plankton diambil sejak bulan Juli sampai September 2018. Pengambilan sampel plankton dengan planktonnet selama tiga bulan pada dua stasiun yang telah ditentukan. Hasil penelitian menunjukkan bahwa jenis plankton terbanyak yang ada di perairan Desa Bahoi adalah fitoplankton kelas Bacillariophyceae dengan (63 genera) sedangkan untuk jenis zooplankton didominasi oleh genus acartia sp kelas Crustaceae. Kepadatan tertinggi plankton terdapat pada stasiun 2 (di luar area budidaya) 3,18 ind/l, kepadatan yang terrendah terdapat pada stasiun 2 dengan waktu pengambilan pagi hari sebesar 1,64 ind/l. Nilai indeks keanekaragaman (H\u27) yaitu 2.5-2.9, menunjukkan bahwa perairan Desa Bahoi termasuk dalam kategori kesuburan sedang dan keanekaragaman jenis plankton yang sedang. Kondisi kualitas air pada saat penelitian secara keseluruhan dapat dikatakan baik dan plankton dapat bertumbuh dan berkembang

PENGARUH PEMANASAN BAHAN BAKAR DENGAN RADIATOR SEBAGAI UPAYA MENINGKATKAN KINERJA MESIN BENSIN

Proses pembakaran bahan bakar di dalam silinder dipengaruhi oleh: temperatur, kerapatan campuran, komposisi, dan turbulensi yang ada pada campuran. Apabila temperatur campuran bahan bakar dengan udara naik, maka semakin mudah campuran bahan bakar dengan udara tersebut untuk terbakar. Tujuan penelitian ini adalah untuk mengetahui pengaruh pemanasan bahan bakar dengan media radiator terhadap konsumsi bahan bakar dan kinerja Motor bakar bensin jenis daihatsu hijet 1000. Metode penelitian menggunakan metode eksperimen. Variabel bebasnya adalah  putaran mesin dan jenis bahan bakar yaitu  premium dan variabel Terikat adalah konsumsi bahan bakar dan daya mesin. Hasil penelitian menunjukkan, bahan bakar yang telah dipanaskan lewat radiator mempunyai keuntungan yaitu menghemat bahan bakar, sebelum dipanaskan sebesar 42 ml/s setelah dipanaskan menjadi 25.8 ml/s pada putaran 2000 rpm. daya efektif yang dihasilkan juga meningkat,sebelum dipanaskan sebesar 18.521 kg/cm² setelah dipanaskan sebesar 20.949 kg/cm² pada putaran 2500 rpm.   Kata Kunci : Konsumsi Bahan Bakar, Pemanasan, Radiato

Parents’ Knowledge, Attitude, and Practice on Childhood Vaccination During the COVID-19 Pandemic in Indonesia

BACKGROUND: Vaccination is known to have an enormous impact on improving child health. In Indonesia, the government has included several vaccines in the national immunization program. OBJECTIVE: This study aimed to investigate parents’ knowledge, attitude, and practice on childhood immunization during the COVID-19 pandemic in Indonesia. METHODS: A valid and reliable questionnaire was delivered to approximately 276 parents in Jakarta and Bandung, representing the epicenter of the pandemic. This study was conducted from June 2020 to February 2021. The correlations between parents’ knowledge, attitudes, and practice with the characteristics of the respondents were investigated. In addition, multiple regression analysis was performed to identify the variables associated with good vaccination practice. RESULTS: The results showed that the mean scores of parents’ knowledge, attitude, and practice on childhood vaccinations were 7.22 (± 1.30) out of 9 points, 3.93 (± 0.31) out of 4 points, and 3.59 (± 0.97) out of 5 points, respectively. Respondents graduated from university were more knowledgeable than those graduated from senior high school (p-value <0.05). Employed participants had better scores in knowledge and practice, compared to unemployed participants (p-value <0.05). CONCLUSION: In conclusion, this study found positive correlations between participants’ knowledge and attitude, knowledge and practice, and attitude and practice on childhood vaccination during the COVID-19 pandemic in Indonesia

Intraocular Pressure Changes During Ramadan Fasting: Effect of Change in Weight and Review of Available Reports

Background: Ramadan fasting (RF) alters many systemic milieus. Dehydration from fasting may cause weight loss, while sedentary lifestyle of some Muslims during fasting results in weight gain. RF is associated with low intraocular pressure (IOP). We aim to find out changes in IOP and its relationship to weight changes during and after Ramadan fasting.Materials and Methods: IOP of eligible males was measured at 0900, 1200 and 1500 hours (hrs). Mean fasting IOP (FIOP) and non-fasting IOP (NFIOP) of both eyes at each period were calculated. Weights were also taken during fasting and after fasting. FIOP and NFIOP were compared using paired t-test for all participants category (1) and participants in different categories of weight changes found during fasting: Those who lost weight during fasting, category (2). Those whose weights were unchanged, category (3), and those who gained weight category (4)Results: There were 51eligible males, category (1) consisting 38, 5 and 8 participants in categories 2, 3 and 4 respectively. Mean weight (Kg) of participants were: fasting 64.000, and non-fasting 65.853, P &lt; .001. At 0900hrs, FIOP was higher than NFIOP but not reaching significant level in all categories. At 1500 hrs however, FIOP was significantly lower than NFIOP for categories 1 and 2 but not significantly for categories 3 and 4.Conclusion: Findings of the few previous works are conflicting. IOP changes during Ramadan may be a manifestation of changes in weight only. We suggest further works should categorize participants according to weight changes during fasting before analysing IOP.Keywords: Ramadan Fasting, Intraocular Pressure, Weight Effec

Immune Status of HIV Positive Children with Acute Rhinosinusitis

The immune status of 25 HIV-positive children with Acute Rhinosinusitis (ARS) has been studied in comparison with the control group of 14 practically healthy children of the same age. HIV-infected patients with ARS have shown deep infringements of the immune status, especially of T-cells and its subpopulations, and impairments of the humoral immunity, suppression of anti-inflammatory cytokine IL-10 and increase of pro-inflammatory IFN-γ. After conducted treatment we have not seen any certain changes of the immune status in HIV positive patients, even in the cases with clinical improvement. It is possible to ascertain only positive changes of IL-10 maintenance and parallel decrease of IFN-γ in the dynamics of treatment