Faktor-Faktor Yang Mempengaruhi Perilaku Merokok Remaja Di Sekolah Menengah Kejuruan Kabupaten Kuningan

Merokok merupakan suatu kebiasaan yang merugikan bagi kesehatan dan jembatan ke penyalahgunaan napza. Rokok diketahui banyak mengandung racun/bahan kimia berbahaya yang dapat menimbulkan berbagai penyakit seperti penyakit jantung, stroke, dan kanker. Menurut WHO (2009) saat ini Indonesia masih menjadi negara ketiga dengan perokok aktif terbanyak di dunia. Penelitian ini bertujuan untuk menganalisis faktor-faktor yang mempengaruhi perilaku merokok pada remaja Sekolah Menengah Kejuruan (SMK) di Kabupaten Kuningan, Jawa Barat. Jenis penelitan ini adalah explanatory study dengan pendekatan cross sectional. Total populasinya adalah 2616 orang dengan sampel sebanyak 347 orang dipilih dengan pendekatan simple random sampling. Analisis bivariat dengan menggunakan uji chi square dan analisis multivariat dengan regresi logistik metode enter. Hasil analisis bivariat menunjukkan ada pengaruh yang signifikan (p<0,05) antara variabel bebas dengan variabel terikat (perilaku merokok). Faktor yang paling dominan mempengaruhi kebiasaan merokok pada remaja SMK adalah pengetahuan remaja tentang rokok dengan nilai eksp (β) = 8.842. Karena nilai eksp (β) > 2 menjadikan hasil analisis ini sah untuk diintepretasikan dalam analisis pengaruh bersama-sama (multivariat)

Deuterium Kinetic Isotope Effects in Microsolvated Gas-Phase E2 Reactions

This work describes the first experimental studies of deuterium kinetic isotope effects (KIEs) for the gas-phase E2 reactions of microsolvated systems. The reactions of F−(H2O)n and OH−(H2O)n, where n = 0, 1, with (CH3)3CX (X = Cl, Br), as well as the deuterated analogs of the ionic and neutral reactants, were studied utilizing the flowing afterglow-selected ion flow tube technique. The E2 reactivity is found to decrease with solvation. Small, normal kinetic isotope effects are observed for the deuteration of the alkyl halide, while moderately inverse kinetic isotope effects are observed for the deuteration of the solvent. Minimal clustering of the product ions is observed, but there are intriguing differences in the nature and extent of the clustering process. Electronic structure calculations of the transition states provide qualitative insight into these microsolvated E2 reactions

Comparison of the Eggs and Cocoons Quality of Some Mulberry Silkworm Hybrid Bombyx mori L.

Sericulture is one of the non-timber forest products (NTFPs) that can help Indonesians live better lives and support environmental improvement. Silk, as a product of sericulture, is one of the five NTFPs that Indonesia has identified as having the ability to boost the nation’s economy and alleviate poverty. However, there are several issues with the development of silk in Indonesia, chiefly issues with the quality of silkworm seedlings and low cocoon yield. Crossbreeding is one method used to boost egg output. This study aimed to evaluate the eggs and cocoons produced by various silkworm (Bombyx mori L.) crosses. The Pustarhut Laboratory hosted the research from May to August 2022. Twelve treatments were employed in the form of crosses using the Randomized Block Design (RBD) method, and each treatment applied three replicates. Overall, the findings demonstrated that the CE cross ((919 x 927) x (804 x p208)) produced eggs (652 eggs) and cocoons of higher quality than other crossings. However, although the egg numbers of CF cross ((919 × 927) × (p208 × 804)) and FC cross ((p208 × 804) × (919 × 927)) produced 622 and 631 eggs, respectively and were significantly different from CE cross, they still produced egg numbers above 600. In addition, they produced cocoon quality that was not significantly different from CE cross. All finding indicates that silkworms from CE, CF, and FC crosses can be used as an alternative to superior silkworm breeding to increase the productivity of silkworm rearing in Indonesia. Keywords: Bombyx mori, cocoon quality, double-cross, seed qualit

WACCM-D Whole Atmosphere Community Climate Model with D-region ion chemistry

Energetic particle precipitation (EPP) and ion chemistry affect the neutral composition of the polar middle atmosphere. For example, production of odd nitrogen and odd hydrogen during strong events can decrease ozone by tens of percent. However, the standard ion chemistry parameterization used in atmospheric models neglects the effects on some important species, such as nitric acid. We present WACCM-D, a variant of the Whole Atmosphere Community Climate Model, which includes a set of lower ionosphere (D-region) chemistry: 307 reactions of 20 positive ions and 21 negative ions. We consider realistic ionization scenarios and compare the WACCM-D results to those from the Sodankylä Ion and Neutral Chemistry (SIC), a state-of-the-art 1-D model of the D-region chemistry. We show that WACCM-D produces well the main characteristics of the D-region ionosphere, as well as the overall proportion of important ion groups, in agreement with SIC. Comparison of ion concentrations shows that the WACCM-D bias is typically within ±10% or less below 70 km. At 70–90 km, when strong altitude gradients in ionization rates and/or ion concentrations exist, the bias can be larger for some groups but is still within tens of percent. Based on the good agreement overall and the fact that part of the differences are caused by different model setups, WACCM-D provides a state-of-the-art global representation of D-region ion chemistry and is therefore expected to improve EPP modeling considerably. These improvements are demonstrated in a companion paper by Andersson et al

Gas-Phase Reactions of Microsolvated Fluoride Ions: An Investigation of Different Solvents

The gas-phase reactions of F^–(DMSO), F^–(CH₃CN), and F^–(C₆H₆) with <i>t</i>-butyl halides were investigated. Reaction rate constants, kinetic isotope effects, and product ion branching ratios were measured using the flowing afterglow selected ion flow tube technique (FA-SIFT). Additionally, the structure of F^–(DMSO) was investigated both computationally and experimentally, and two stable isomers were identified. The reactions generally proceed by elimination mechanisms; however, the reaction of F^–(C₆H₆) with <i>t</i>-butyl chloride occurs by a switching mechanism. These reactions are compared to previous studies of microsolvated reactions of <i>t</i>-butyl halides where the solvent molecules were polar, protic molecules

Reactions of Ions with Ionic Liquid Vapors by Selected-Ion Flow Tube Mass Spectrometry

Room-temperature ionic liquids exert vanishingly small vapor pressures under ambient conditions. Under reduced pressure, certain ionic liquids have demonstrated volatility, and they are thought to vaporize as intact cation−anion ion pairs. However, ion pair vapors are difficult to detect because their concentration is extremely low under these conditions. In this Letter, we report the products of reacting ions such as NO⁺, NH₄⁺, NO₃⁻, and O₂⁻ with vaporized aprotic ionic liquids in their intact ion pair form. Ion pair fragmentation to the cation or anion as well as ion exchange and ion addition processes are observed by selected-ion flow tube mass spectrometry. Free energies of the reactions involving 1-ethyl-3-methylimidazolium bis-trifluoromethylsulfonylimide determined by ab initio quantum mechanical calculations indicate that ion exchange or ion addition are energetically more favorable than charge-transfer processes, whereas charge-transfer processes can be important in reactions involving 1-butyl-3-methylimidazolium dicyanamide