Skin color-specific and spectrally-selective naked-eye dosimetry of UVA, B and C radiations.

Spectrally-selective monitoring of ultraviolet radiations (UVR) is of paramount importance across diverse fields, including effective monitoring of excessive solar exposure. Current UV sensors cannot differentiate between UVA, B, and C, each of which has a remarkably different impact on human health. Here we show spectrally selective colorimetric monitoring of UVR by developing a photoelectrochromic ink that consists of a multi-redox polyoxometalate and an e- donor. We combine this ink with simple components such as filter paper and transparency sheets to fabricate low-cost sensors that provide naked-eye monitoring of UVR, even at low doses typically encountered during solar exposure. Importantly, the diverse UV tolerance of different skin colors demands personalized sensors. In this spirit, we demonstrate the customized design of robust real-time solar UV dosimeters to meet the specific need of different skin phototypes. These spectrally-selective UV sensors offer remarkable potential in managing the impact of UVR in our day-to-day life.

The Bayesian adaptive lasso regression.

Classical adaptive lasso regression is known to possess the oracle properties; namely, it performs as well as if the correct submodel were known in advance. However, it requires consistent initial estimates of the regression coefficients, which are generally not available in high dimensional settings. In addition, none of the algorithms used to obtain the adaptive lasso estimators provide a valid measure of standard error. To overcome these drawbacks, some Bayesian approaches have been proposed to obtain the adaptive lasso and related estimators. In this paper, we consider a fully Bayesian treatment for the adaptive lasso that leads to a new Gibbs sampler with tractable full conditional posteriors. Through simulations and real data analyses, we compare the performance of the new Gibbs sampler with some of the existing Bayesian and non-Bayesian methods. Results show that the new approach performs well in comparison to the existing Bayesian and non-Bayesian approaches.

Heavy metals in vegetables sold in the local market in Jordan.

Heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in various vegetables (cabbage, green onion, lettuce, parsley, rocket, spinach, carrot, onion, potato and cauliflower) from the market in Jordan were measured using inductively coupled plasma-mass spectrometry. As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged from 0.009-0.275 mg kg(-1) wet weight, 0.004-0.060 mg kg(-1), 0.003-0.401 mg kg(-1), 0.105-3.51 mg kg(-1), 0.15-1.15 mg kg(-1), 0.93-14.39 mg kg(-1), 0.044-0.702 mg kg(-1), 0.072-0.289 mg kg(-1) and 2.23-6.65 mg kg(-1), respectively. Parsley, followed by spinach, contained the highest concentration of heavy metals. Onion contained high levels of toxic heavy metals. The content of Cu in parsley and spinach and Pb in onion exceeded the Codex limits. However, the daily intake of heavy metals from the tested vegetables was lower than the maximum limits for allowable intake.

Prevalence of antibodies to human T-lymphotropic viruses types I and II among healthy blood donors.

OBJECTIVE: To assess the prevalence of human T-cell lymphotropic virus type I and type II antibodies in blood donors donating blood for various reasons in a University hospital and to compare the results with other reports from the Kingdom of Saudi Arabia (KSA), and elsewhere. METHODS: A 7-year retrospective review of blood bank records for results of serological tests at the King Fahd Hospital of the University, Al-Khobar, KSA, from January 1995 to December 2001 was conducted. The study included review of blood donor questionnaire cards as well as extraction of any other relevant information. RESULTS: The results showed that the total number of blood donor units drawn during the 7- year period was 23493 units. A total of 50 units were found repeatedly reactive by enzyme immunoassay screening test (0.2%). Only 12 (0.05%) were confirmed reactive by western blot test and 4 were found to be indeterminate. Nine (0.04%) of the confirmed samples were from Saudi nationals. All 3 non-Saudi confirmed reactive donors were Indian nationals, while the 4 indeterminate cases, 2 were Saudis and 2 were Egyptians. A statistical estimate of the maximal risk of finding a positive donor in this donor population subgroup is in the order of 0.05%. The number of Saudi blood donors during this study was 16434 (80.3%) and non-Saudi donors was 4027 (19.7%). CONCLUSION: Based on these results it is shown that the prevalence of this virus is still low among blood donors in the Eastern region of Kingdom of Saudi Arabia.