Development of a Solar-Powered IoT-Based Instrument for Automatic Measurement of Water Clarity.

Water clarity is the most common indicator of water quality. The purpose of the study was to develop an instrument which can automatically measure water clarity in place of manual measurement by Secchi disk. The instrument is suspended by buoys at the water surface and uses solar energy to measure the light intensity of LED bulbs after passing through a water column; the result is then converted to Secchi depth by using a regression function. Measurement data are stored in a cloud server so that mobile users can access via an Internet connection. Three experiments were conducted to examine the instrument performance: (i) to ensure light intensity of the LED bulbs is strong enough to pass through the water column; (ii) to determine the regression relationship between the measured light intensity of the instrument and Secchi depth; and (iii) to evaluate the coefficient of variation (CV) of the measured water clarity when using our instrument and a conventional Secchi disk. Experiment results show that the measured values of light intensity are stable with the average CV = 5.25%. Moreover, although there are slight differences between the Secchi depth measured by our instrument and those measured by Secchi disk, the measurements by our instrument can efficiently replace the measurements by conventional Secchi disk, which can be affected by weather conditions as well as by human subjectivity.

Hepatitis B Screening and Awareness in the Milwaukee Hmong Community.

INTRODUCTION: Hepatitis B virus (HBV) infection disproportionately affects the Hmong ethnic group, with reported US prevalence rates up to 20%, but data for Wisconsin's large Hmong community is lacking. We assessed the prevalence of HBV at Hmong screening events and whether small-group counseling affects HBV knowledge. METHODS: Free HBV screening events were held in Milwaukee, Wisconsin at a Hmong market, a local church, and annual Hmong New Year festival. Eligible Hmong subjects age 18 years and older also were invited to complete a 15-point survey on HBV knowledge at baseline and after education sessions. Hmong interpreters were available, and free HBV screening was offered. RESULTS: A total of 187 participants were tested for HBV, and 161 completed surveys. After education sessions, the mean knowledge score rose to 10.6 (71%) vs the pre-education score of 6.7 (45%) (P <0.0001). Active HBV [HBsAg(+) HBsAb(-)] was diagnosed in 18 participants (9.6%), 53 (28.3%) were susceptible [HBsAg(-) and HBsAb(-)], 5 (3.4%) were in the gray zone [HBsAg(-) with low/inadequate HBsAb(+) titer], and the remaining 110 (58.8%) were immune [HBsAg(-)/HBsAb(+)]. Of the 18 individuals with active HBV, 13 were male and 5 were female [age range 24-66]. CONCLUSION: Despite evidence that small-group education with visual aids is effective in enhancing HBV knowledge in the Hmong population, a significant knowledge gap remained on post-education scores, suggesting that better tools or repeated interventions may be warranted. While we acknowledge that this convenience sampling may have introduced biases, the rate of active HBV infection in Wisconsin is much higher than general US population reports, and a quarter of those tested were found to be susceptible to HBV.

Nicotinamide; antioxidative and DNA hypomethylation effects in plant cells.

The effects of nicotinamide (NIC) and its natural plant metabolites nicotinic acid (NIA) and trigonelline (TRIG) were studied with respect to defense in plant cell cultures. NIC and NIA could protect against oxidative stress damage caused by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH), which generates free radicals. Damage was analyzed as DNA strand breaks in cell cultures of Pisum sativum (garden pea), Daucus carota (carrot), Populus tremula L. × P. tremuloides (hybrid aspen) and Catharanthus roseus (Madagascar periwinkle), monitored by single cell gel electrophoresis (comet assay), and assays of cell leakage in C. roseus. The activities of aconitase and fumarase enzymes, which have key roles in energy metabolism, were analyzed in P. sativum cultures after treatment with NIC or NIA. Aconitase activity was increased by NIA, and fumarase activity was increased by both compounds. These compounds were shown to promote glutathione metabolism in P. sativum cultures, and NIC was shown to have a global DNA hypomethylating effect. Neither TRIG nor poly(ADP-ribose) polymerase (PARP) inhibitor 3-aminobenzamide offered any protection against DNA damage or cell leakage, nor did they promote aconitase or fumarase activities, or glutathione metabolism. By this broad approach addressing multiple biochemical factors and different plant species, we demonstrate that NIC and NIA protect plant cells from oxidative stress, and that NIC clearly exerts an epigenetic effect; decreased DNA methylation. This indicates that these compounds have important roles in the regulation of metabolism in plant cells, especially in connection to stress.