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In forensic genetics, the analysis of postmortem bones is one of the most challenging due to the low quantity of degraded endogenous DNA. The most widely used approach for sample preparation, in those cases, is pulverizing the bone. However, processing pulverized bone is extremely delicate, requiring strict laboratory conditions and operating procedures. In fact, several recent publications have focused on non-powder approaches. The objectives of this study were, thus, to validate a non-powder protocol for DNA extraction from forensic bones and an alternative pretreatment, large fragment demineralization (LFD). Thirty human femurs and tibiae received by the Legal Medicine Institute of Brescia, Italy, were included in the study. Bone powder and one transversal section of the diaphysis were sampled from each bone. DNA extraction from the powder was carried out using PrepFiler BTA (BTA), while the transversal section was submitted to the alternative demineralizing pretreatment (LFD) followed by DNA extraction using the QIAamp DNA Investigator. DNA extracts were assessed for human DNA quantity and degradation by means of a validated in-house qPCR assay and amplified with commercial kits. Inhibition assessment was carried out through Quality Sensor analysis using 24plex QS Kit. The differences in quantity, quality of human DNA, and number of alleles detected between both methods were comparable and not statistically significant. We propose the use of the LFD protocol as a complementary approach capable of confirming the genotypes or detect alleles not observed using BTA, without the need for pulverization. [ABSTRACT FROM AUTHOR]

The long-term viability of many construction projects is heavily dependent on the soundness of the underlying subgrade soil which needs to be capable of supporting loads from structures without undergoing excessive deformation or volume changes. However, in certain locations geotechnical engineers face repeated problems in the design of substructures due to the presence of expansive soils. Light structures are especially susceptible to damage in such situations which can result in cracks in walls, beams, columns and on-grade slabs. One extensively used way of overcoming such problems is to improve the soil by stabilizing it with cement and/or lime which prevents this unwanted behavior. Most previous research conducted on expansive soils focused on studying the effects of treatment on the physical properties of the soil without detailed examination of the physicochemical mechanism of the process, although some studies surveyed the effect of the treatment using cement and lime on the mineralogical composition and newly formed pozzolanic compounds. In this research the mineralogical changes due to lime and cement additions to two different expansive soils from Saudi Arabia, in particular, were investigated using X-ray diffraction. The results of this work indicate that addition of lime or cement to the soils tested resulted in the formation of pozzolanic compounds, namely, calcium silicate hydrate and calcium aluminate hydrate together with calcite (CaCO). The soil improvements are compared for cement and lime. Changes in potassium, aluminum and silicon were also determined and interpreted in terms of the soil mineralogy. It was concluded that pozzolanic compounds play a significant role in reducing the swelling and increasing the strength. [ABSTRACT FROM AUTHOR]

In this study, an incident pulse signal of several harmonics (i.e., multiples of the fundamental frequency) was used as a source in the time domain reflectometry (TDR) probing technique. Reflected signals were captured by an oscilloscope and their characteristics were determined via eigendecomposition. Autoregressive modeling and singular value decomposition were used to calculate the eigenvalues and the most significant ones were identified based on power spectrum. A multivariate statistical analysis was performed for the two most dominant eigenvalues, which are dependent on water content and salt concentrations, and regression equations were obtained. To determine the water content and salt concentrations in terms of the first and second eigenvalues, a modified Powell hybrid algorithm was used to solve the obtained system of nonlinear equations. Actual and predicted results are in agreement indicating that the developed method is very successful in predicting water content and salt concentrations. Furthermore, on comparing the eigendecomposition method with Fourier spectral analysis, one can observe that the former is superior in predicting water content and salt concentrations. [ABSTRACT FROM AUTHOR]

The water resources in the arid region like Kuwait are a scarce commodity. With the increasing population, industry and urbanization have lead to the demand of water resources with respect to both in quantity and quality. Therefore, quantification of submarine groundwater discharge is essential for sustainable groundwater management. Moreover, submarine groundwater discharge plays a vital role in delivering nutrients, dissolved carbon, and trace elements to the sea. This study used the naturally occurring radioactive isotopes to identify and estimate the SGD in the coastal strip of Kuwait along the Arabian Gulf. The study gains its significance in determining the loss of brackish groundwater from inland, in the arid region. The groundwater samples were collected from wells along the coast. Seawater samples were collected from Kuwait bay and open sea in transects. Samples were analyzed for major ions, nutrients, and 223Ra, 224Ra, 226Ra, and 228Ra. Box model and offshore gradient model approaches were used to estimate the SGD. The variation of 223Ra, 224Ra, 226Ra, and 228Ra concentrations was studied in different transects, and it was inferred to be influenced by the Kuwait coastal jet in the territorial waters. The water mass residence time calculated for the Kuwait Bay and the open sea ranged from 10 to 58 and 12 to 64 days, respectively. The 223Ra-based horizontal eddy diffusion coefficients for the Kuwait Bay and the south Arabian Gulf were 205.1 and 827.5 m2/s, respectively. The estimation of SGD fluxes in the Kuwait Bay using box model approach based on the spatial distribution of 226Ra and 228Ra were 3.05 × 106 and 5.46 × 106 m3/day, respectively. Similarly, the estimated SGD fluxes for the south Arabian Gulf by offshore gradient model using 226Ra and 228Ra concentrations were 2.92 × 108 and 3.0 × 107 m3/day, respectively. The nutrient fluxes from groundwater to Kuwait Bay and open sea were estimated for PO43−-P, SiO2-Si, and NO3−-N using box model and offshore gradient model approach. [ABSTRACT FROM AUTHOR]