Pengaruh Pasta Gigi mengandung Xylitol terhadap Pertumbuhan Streptococcus mutans Serotipe E (In Vitro)

Streptococcus mutans serotype E is a major bacterium causing caries, and widely present in dental plaque. Dentifrices containing xylitol have been shown to inhibit the growth of these mutans streptococci. The aim of the study was to identify the influence of dentifrice containing xylitol on S. mutans serotype E (in vitro). The 1:1 solution of dentifrice containing xylitol was diluted to the test concentrations of 100%, 10%, 1%, 0.1%, 0.01%, and 0.001%, in addition to positive and negative control groups. These solutions were examined in S. mutans serotype E test cultures by the diffusion method. The resulting inhibition zone was 2.16 mm at a concentration of 10%, and 3.0 mm at a concentration of 100%. Zero zone size was found at all other test concentrations, and a significant (Spearman) negative correlation was indicated between the concentration of dentifrice and the growth of mutans streptococci (p<0.05). The MIC was not been identified, but MBC was 10%. In conclusion, the dentifrice containing xylitol can significantly inhibit the growth of S. mutans serotype E at least at dentrifice concentrations of 5-10%.DOI: 10.14693/jdi.v15i1.7

Effects of Phloroglucinol on In Vitro Methanogenesis, Rumen Fermentation, and Microbial Population Density

This study investigated the effect of phloroglucinol (1,3,5-trihydroxybenzene) supplementation alone on methane production, rumen fermentation profiles, and microbial population structure of mixed in vitro cultures. Treatments included a control group containing a substrate with no supplement, and substrates supplemented with 2, 4, 6, 8, or 10 mmol/L of phloroglucinol. The results revealed that phloroglucinol was able to decrease methane production in a dose-dependent manner. The highest decrease was observed with 8 and 10 mmol/L supplementations. The relative quantity of methanogen was not affected by phloroglucinol, whereas genus Coprococcus was increased with increasing concentrations of phloroglucinol (p<0.05). Total gas production, dry matter digestibility (DMD), and NH3-N were significantly lowered by phloroglucinol (p<0.001). Total short-chain fatty acid (SCFA) concentration was not affected by phloroglucinol. Acetate proportion increased with the addition of phloroglucinol at the expense of propionate (p<0.001). This might indicate the redirection of [H] from methane to acetate, and might be related to methane inhibition.. Our study concluded that supplementation of phloroglucinol alone could decrease methane production by inhibiting nutrient digestibility in the rumen and by possible redirection of rumen fermentation to acetate production. Genus Coprococcus could be an important actor for phloroglucinol metabolism in the rumen

Soundscape assessment: Towards a validated translation of perceptual attributes in different languages

The recently published ISO/TS 12913-2:2018 standard aims to provide researchers and practitioners around the world with a reliable questionnaire for soundscape characterization. The ISO Technical Specifications report protocols and attributes grounded in the soundscape literature, but only includes an English version. The applicability and reliability of these attributes in non-English speaking regions remains an open question, as research investigating translations of soundscape attributes is limited. To address this gap, an international collaboration was initiated with soundscape researchers from all over the world. Translation into 15 different languages, obtained through focus groups and panels of experts in soundscape studies, are proposed. The main challenges and outcomes of this preliminary exercise are discussed. The long-term objective is to validate the proposed translations using standardized listening experiments in different languages and geographical regions as a way to promote a widespread use of the soundscape attributes, both in academia and practice, across locations, populations and languages

Cardiovascular disease, chronic kidney disease, and diabetes mortality burden of cardiometabolic risk factors from 1980 to 2010: A comparative risk assessment

Background: High blood pressure, blood glucose, serum cholesterol, and BMI are risk factors for cardiovascular diseases and some of these factors also increase the risk of chronic kidney disease and diabetes. We estimated mortality from cardiovascular diseases, chronic kidney disease, and diabetes that was attributable to these four cardiometabolic risk factors for all countries and regions from 1980 to 2010. Methods: We used data for exposure to risk factors by country, age group, and sex from pooled analyses of population-based health surveys. We obtained relative risks for the effects of risk factors on cause-specific mortality from meta-analyses of large prospective studies. We calculated the population attributable fractions for each risk factor alone, and for the combination of all risk factors, accounting for multicausality and for mediation of the effects of BMI by the other three risks. We calculated attributable deaths by multiplying the cause-specific population attributable fractions by the number of disease-specific deaths. We obtained cause-specific mortality from the Global Burden of Diseases, Injuries, and Risk Factors 2010 Study. We propagated the uncertainties of all the inputs to the final estimates. Findings: In 2010, high blood pressure was the leading risk factor for deaths due to cardiovascular diseases, chronic kidney disease, and diabetes in every region, causing more than 40% of worldwide deaths from these diseases; high BMI and glucose were each responsible for about 15% of deaths, and high cholesterol for more than 10%. After accounting for multicausality, 63% (10·8 million deaths, 95% CI 10·1-11·5) of deaths from these diseases in 2010 were attributable to the combined effect of these four metabolic risk factors, compared with 67% (7·1 million deaths, 6·6-7·6) in 1980. The mortality burden of high BMI and glucose nearly doubled from 1980 to 2010. At the country level, age-standardised death rates from these diseases attributable to the combined effects of these four risk factors surpassed 925 deaths per 100 000 for men in Belarus, Kazakhstan, and Mongolia, but were less than 130 deaths per 100 000 for women and less than 200 for men in some high-income countries including Australia, Canada, France, Japan, the Netherlands, Singapore, South Korea, and Spain. Interpretation: The salient features of the cardiometabolic disease and risk factor epidemic at the beginning of the 21st century are high blood pressure and an increasing effect of obesity and diabetes. The mortality burden of cardiometabolic risk factors has shifted from high-income to low-income and middle-income countries. Lowering cardiometabolic risks through dietary, behavioural, and pharmacological interventions should be a part of the global response to non-communicable diseases. Funding: UK Medical Research Council, US National Institutes of Health. © 2014 Elsevier Ltd

Performance Testing of Indonesian Hydrocarbon Refrigerants

In conjunction with the CFC phase out, IURC-ES ITB has been concentrating its research of HC refrigerant on 'propane natural butane' (PNB) refrigerant. The test results obtained in IURC-ES ITB during the development of the PNB refrigerant showed that PNB has better performance than PIB and CFC-12. The field tests of PNB also showed the similar results. Recently, to reconï¬rm the previous test results, the performance of PNB, PIB and CFC-I2 were compared in a series of performance tests in the LTMP Serpong. The tests also show that PNB consistently has better performance compared to PIB and CFC-12. This paper also reports the current development of PNB refrigerant in IURC-ES ITB

Performance Comparison of CFC12, HCR12 and HCR12+LFS as Refrigerants

Additional concern about warming of the global environment through the greenhouse effect has necessitated selection of compounds with shorter atmospheric lifetimes and higher energy efficiencies as substitute refligerants for Heating, Air Conditioning, and refrigerating equipment.Several substitute compounds of the hidrocarbon were identified by similarities in normal boiling points and corresponding saturated vapor pressure characteristics. Sample quantities were obtained from ITB (Two sample corresponds with CFCIZ named Hycool HCRI2 and Hycool HCR12+LFS). Performance comparisons among these refrigerants are performed utilizing Air Conditioning System test facility in Laboratory for Thermodynamics, Engines and Propulsion System (LIMP "“ BPP Teknologi). The results show that these alternatives refrigerants exhibit better performance than CFC I 2 at the predetermined operating conditions

Study Experimental Pengaruh Spark Plug Clearance terhadap Daya dan Efisiensi pada Motor Matic

Pada internal combustion engine dipengaruhi oleh proses pembakaran, sedangkan proses pembakaran dipengaruhi oleh berbagai variabel. Dari berbagai variabel tersebut salah satunya adalah celah busi. Celah busi ini akan mempengaruhi kualitas loncatan bunga api. Dengan demikian perlu dilakukan penelitian untuk mengetahui pengaruh spark plug clearence terhadap daya dan efisiensi pada motor matic. Penelitian dilakukan menggunakan metode experimental. Kendaraan yang digunakan adalah mesin Yamaha Mio matic 113.7 cc silinder tunggal. Menggunakan 3 variasi celah busi yaitu 0.6 mm, 0,8 mm, 1 mm. Sedangkan putaran juga divariasikan mulai dari 3000 rpm, 4000 rpm, 5000 rpm, 6000 rpm dan 7000 rpm. Hasil penelitian menunjukkan bahwa daya roda yang tertinggi dihasilkan engine dengan jarak elektroda busi 0,60 mm menghasilkan 4,85 HP di putaran 7000 rpm. Daya bahan bakar tertinggi terjadi pada putaran 7000 rpm dengan jarak elektroda busi 0,60 mm, dengan nilai sebesar 7,84 HP. Effisiensi terbesar pada celah busi 0,60 mm yaitu 61,82 % di putaran 7000 rpm