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Abstract Hybrid alumina (Al 2 O 3) ceramic nanocomposites containing 3 wt% silicon carbide nanoparticles (SiCnp) and 0.5 wt% multilayer graphene (MLG) were consolidated to near theoretical density (99%) by an inductive hot-pressing (IHP) technology. The enhanced fracture toughness and hardness by 97% and 15% respectively, for the hybrid nanocomposites over the reference Al 2 O 3 were attributed to the higher densification, uniformly dispersed reinforcing constituents within the base matrix, toughening mechanisms of crack-deflection by the 0D-SiCnp and grain-anchoring as well as crack-bridging induced by the 2D-MLG. Thermal investigations of the hybrid nanocomposite verified the occurrence of a chemical reaction at the MLG/Al 2 O 3 interface and thermal diffusion at SiCnp/Al 2 O 3 interface during inductive hot-pressing. The bonding characteristics and interfacial microstructure were appraised by infra-red spectroscopy and high-resolution TEM microscope. Furthermore, the thermal stability in different gaseous environments and the ballistic performance of the hybrid nanocomposites were characterized and discussed. The produced hybrid nanocomposites may be suitable for high-temperature aerospace structural parts and may have applications in high-velocity impact technology. Highlights • Dense hybrid nanocomposites were prepared by inductive hot pressing method. • The hybrid nanocomposites demonstrated 97% higher fracture toughness over Al 2 O 3. • Hybrid nanocomposites manifested high thermal stability and ballistic performance. • Reinforcing phases (SiC and MLG) formed sturdy interface with Al 2 O 3 matrix. [ABSTRACT FROM AUTHOR]

A method based on regression modeling was developed to discern the contribution of component chemicals to the toxicity of highly complex, environmentally realistic mixtures of disinfection byproducts (DBPs). Chemical disinfection of drinking water forms DBP mixtures. Because of concerns about possible reproductive and developmental toxicity, a whole mixture (WM) of DBPs produced by chlorination of a water concentrate was administered as drinking water to Sprague–Dawley (S–D) rats in a multigenerational study. Age of puberty acquisition, i.e. , preputial separation (PPS) and vaginal opening (VO), was examined in male and female offspring, respectively. When compared to controls, a slight, but statistically significant delay in puberty acquisition was observed in females but not in males. WM-induced differences in the age at puberty acquisition were compared to those reported in S–D rats administered either a defined mixture (DM) of nine regulated DBPs or individual DBPs. Regression models were developed using individual animal data on age at PPS or VO from the DM study. Puberty acquisition data reported in the WM and individual DBP studies were then compared with the DM models. The delay in puberty acquisition observed in the WM-treated female rats could not be distinguished from delays predicted by the DM regression model, suggesting that the nine regulated DBPs in the DM might account for much of the delay observed in the WM. This method is applicable to mixtures of other types of chemicals and other endpoints. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel sensitivity analyses of alternative toxic equivalency factors (TEFs). [•] Characterized uncertainty in dioxin toxic equivalency (TEQ) intakes. [•] Estimated U.S. mean daily TEQ intake of 23pg/day from 8 food categories. [•] Dairy (other than milk), beef, and seafood contribute most to TEQ intake. [•] TEF probability distributions needed to conduct probabilistic uncertainty analyses. [ABSTRACT FROM AUTHOR]

Abstract: Previous epidemiological studies in Massachusetts have reported a risk of adverse health outcomes in relation to disinfection by-product (DBP) exposures. Measurement error due to the use of indirect exposure surrogates can lead to misclassification bias in epidemiological studies; therefore, it is important to characterize exposure variability in these populations to assess the potential for exposure misclassification. We used 19,944 trihalomethane (THM) samples and 9291 haloacetic acid (HAA) samples collected in 201 public water systems (PWSs) in Massachusetts to examine temporal variability under different drinking water sources and disinfection types. Annual and seasonal variability was also examined in 46 PWSs with complete quarterly THM4 (i.e., the sum of 4 individual THMs) data from 1995 to 2004 and 19 PWSs with complete HAA5 (i.e., the sum of 5 individual HAAs) data from 2001 to 2004. The quarterly ratio of THM4 and HAA5 and correlations between THM4, HAA5 and individual DBP species were examined to determine the adequacy of using different exposure surrogates in epidemiological studies. Individual PWSs were used to examine monthly variability in relation to quarterly averages. Based on all available matched samples (n=9003) from 1995 to 2004 data, we found a correlation of 0.52 for THM4 and HAA5. The correlation was stronger among the 62 ground water systems (r s =0.62) compared to the 81 surface water (r s =0.45) and 40 mixed water (r s =0.39) systems. Mean THM4 levels were fairly stable over the 10-year study period for 46 PWSs including 39 PWSs that did not change disinfection. Large reductions (∼40μg/L) in mean THM4 data were found among seven systems that switched from chlorination to alternative disinfectants. As expected, the highest mean THM4 values were detected for Quarter 3, while the lowest values were found in Quarter 1. The highest HAA5 values were detected in Quarters 2 and 3 and the lowest was found in Quarter 4. Data from four systems showed mean differences up to 66μg/L (67% change) in successive months and by 46μg/L compared to quarterly mean concentrations. Although longer-term disinfection by-product temporality may be minimal in this study population, the use of monthly average concentrations for exposure assessment may be needed for some PWSs to minimize misclassification of narrow critical periods of exposure in epidemiological studies. [Copyright &y& Elsevier]

The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose–response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, ternary and quaternary mixtures composed of hydrophobic organic compounds (HOCs). The toxicity of each individual component and mixture was determined using the Vibrio fischeri bioluminescence inhibition assay. For each combination of chemicals specified by the 2 n factorial design, the percent deviation of the predicted toxic effect from the measured value was used to characterize mixtures as synergistic (positive deviation) and antagonistic (negative deviation). An arbitrary classification scheme was proposed based on the magnitude of deviation (d) as: additive (⩽10%, class-I) and moderately (10< d ⩽30%, class-II), highly (30< d ⩽50%, class-III) and very highly (>50%, class-IV) antagonistic/synergistic. Naphthalene, n-butanol, o-xylene, catechol and p-cresol led to synergism in mixtures while 1, 2, 4-trimethylbenzene and 1, 3-dimethylnaphthalene contributed to antagonism. Most of the mixtures depicted additive or antagonistic effect. Synergism was prominent in some of the mixtures, such as, pulp and paper, textile dyes, and a mixture composed of polynuclear aromatic hydrocarbons. The organic chemical industry mixture depicted the highest abundance of antagonism and least synergism. Mixture toxicity was found to depend on partition coefficient, molecular connectivity index and relative concentration of the components. [Copyright &y& Elsevier]

Toxic organic chemicals present in industrial effluents were screened to design mixtures for examining the significant main and interaction effects among mixture components. A set of five four-component mixtures was selected by examining effluents from organic chemical, textile-dye, pulp-paper and petroleum refinery industries. The screening was based on their discharge, solubility, toxicity and volatility. A 2 n full factorial approach was used in designing the mixtures, containing components at two dose levels, EC10(−) and EC40(+). Each mixture resulted in 16 combinations. Mixture toxicity was measured using the Vibrio fischeri bioluminescence inhibition assay. The main effects and binary, ternary and quaternary interaction effects were determined and the significance of effects was evaluated using normal order score and multifactor ANOVA. The organic chemicals retained after screening included, acetaldehyde, aniline, n-butanol, p-cresol, catechol, ethylbenzene, naphthalene, phenol, 1,2,4 trimethylbenzene and o-xylene. In all mixtures, the magnitude of main effects was more significant than the interaction effects. The trend in the main effect of components in any mixture was affected by the trends in the physico-chemical properties of the components, i.e., partition coefficient, molecular size and polarity. In some mixtures, a component with significantly higher concentration and significantly lower toxicity was found to depict a relatively high main effect, as observed for acetaldehyde in mixture I and n-butanol in mixture III. Normal order score approach failed to identify the significant interaction effects that could be identified using multifactor ANOVA. In general, the binary interactions were more significant than the ternary and quaternary interactions. [Copyright &y& Elsevier]

Abstract: The toxicity of 14 industrially relevant organic chemicals was determined using freshly grown Vibrio fischeri bioluminescence inhibition assay. The results were compared to lyophilized V. fischeri, 96h fish, 48h Daphnia magna and 95h green algae bioassays. Reliability of octanol–water partition coefficient (K ow), and first order simple and valence molecular connectivity index (1 χ, 1 χ v) based regression models for predicting toxicity to V. fischeri was studied. Correlations were obtained between freshly grown V. fischeri data (Log(EC50)) and Log(K ow), molecular connectivity indices (1χ, 1 χ v), energy of the highest occupied (E HOMO) and lowest unoccupied (E LUMO) molecular orbitals, and their difference (E LUMO − E HOMO). A good match was observed between V. fischeri assay conducted with freshly grown and lyophilized culture (r 2 =0.90). Good correlations (r 2 >0.95) were obtained with all the other bioassays after excluding compounds with Log(K ow) less than 2.0. Available regression models based on Log(K ow) and 1 χ v yielded lower toxicity values. V. fischeri bioassay showed fairly good correlation with Log(K ow), 1 χ and 1 χ v (r 2 >0.75) but poor correlation with E HOMO, E LUMO and (E LUMO − E HOMO) in presence of polar compounds. E HOMO and E LUMO values are affected by polarity and can be used along with Log(K ow) and 1 χ v for generating better predictive models. [Copyright &y& Elsevier]

Abstract: Evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on toxicity/ecotoxicity. Since assays based on animals, plants and algae are expensive, time consuming and require large sample volume, recent studies have emphasized the benefits of rapid, reproducible and cost effective bacterial assays for toxicity screening and assessment. This review focuses on a bacterial assay, i.e., Vibrio fischeri bioluminescence inhibition assay, which is often chosen as the first test in a test battery based on speed and cost consideration. The test protocol is simple and was originally applied for aqueous phase samples or extracts. The versatility of the assay has increased with subsequent modification, i.e., the kinetic assay for turbid and colored samples and the solid phase test for analyzing sediment toxicity. Researchers have reported the Vibrio fischeri bioluminescence assay as the most sensitive across a wide range of chemicals compared to other bacterial assays such as nitrification inhibition, respirometry, ATP luminescence and enzyme inhibition. This assay shows good correlations with other standard acute toxicity assays and is reported to detect toxicity across a wide spectrum of toxicants. [Copyright &y& Elsevier]

A novel controller based on multiresolution decomposition using wavelets is presented. The controller is similar to a proportional-integral-derivative (PlD) controller in principle and application. The output from a motion control system represents the cumulative effect of uncertainties such as measurement noise, frictional variation, and external torque disturbances, which manifest at different scales. The wavelet is used to decompose the error signal into signals at different scales. These signals are then used to compensate for the uncertainties in the plant. This approach provides greater expanse over the degree of control applied to the system. Through hardware and simulation results on motion control systems, this controller is shown to perform better than a PID in terms of its ability to provide smooth control signal, better disturbance, and noise rejection. [ABSTRACT FROM AUTHOR]

The paper presents a speech coding algorithm for operation at 11025 samples/s. The coder provides improved speech quality and compatibility with the MS-Windows multimedia environment. The coding algorithm has been developed by adapting the ITU G729 and enhancing it with some recent developments in the medium band coding. The coder operates over a band of frequencies ranging from 20 to 5400 Hz at a bit rate of 8.9 kbit/s. Application of this coder includes intranet VoIP, voice chatting, multimedia communications, and voice archiving. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The estimation of spatiotemporal variability of vegetation health and associated climatic variables is a prerequisite for efficient management of mountain ecosystems. The present study aimed to quantify the changing effect of different climatic parameters on vegetation health in Khyber Pakhtunkhwa, Pakistan, from 2012 to 2021. The association between NDVI and three explanatory variables, i.e., temperature, precipitation, and wind speed, was analyzed using geostatistical model optimization and stationarity index analysis. Results showed that local model GWR presented optimal results owing to its ability to deal with spatial non-stationarity and stochasticity inherent in regression relationships. The most dominant climatic factor influencing vegetation dynamics in KPK was temperature, followed by wind speed and precipitation. However, there was a gradual decline in the influence of temperature in controlling vegetation dynamics after 2018, and precipitation emerged to be the major determinant. Moreover, the stationarity index was calculated at multi-scales to determine the operational scale range for each climatic variable. The scale-dependency of NDVI-T relationship exhibited highest spatial heterogeneity, up to a distance of 600 km. Overall, geostatistical modeling using earth observation datasets enabled insightful understanding of spatiotemporal variations in vegetation response to climate change, necessary for sustainable development and responsive climate action. [ABSTRACT FROM AUTHOR]

Abstract: Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking water research has been limited because the selected NOM sources are atypical of most drinking water sources. The purpose of this research was to demonstrate that reconstituted NOM from a lyophilized reverse-osmosis (RO) concentrate of a typical drinking water source closely represents DBP formation in the original NOM. A preliminary experiment assessed DBP formation kinetics and yields in concentrated NOM, which demonstrated that chlorine decays faster in concentrate, in some cases leading to altered DBP speciation. Potential changes in NOM reactivity caused by lyophilization were evaluated by chlorination of lyophilized and reconstituted NOM, its parent RO concentrate, and the source water. Bromide lost during RO concentration was replaced by adding potassium bromide prior to chlorination. Although total measured DBP formation tended to decrease slightly and unidentified halogenated organic formation tended to increase slightly as a result of RO concentration, the changes associated with lyophilization were minor. In lyophilized NOM reconstituted back to source water TOC levels and then chlorinated, the concentrations of 19 of 21 measured DBPs, constituting 96% of the total identified DBP mass, were statistically indistinguishable from those in the chlorinated source water. Furthermore, the concentrations of 16 of 21 DBPs in lyophilized NOM reconstituted back to the RO concentrate TOC levels, constituting 86% DBP mass, were statistically indistinguishable from those in the RO concentrate. This study suggests that lyophilization can be used to preserve concentrated NOM without substantially altering the precursors to DBP formation. [Copyright &y& Elsevier]

Electroencepholographs (EEGs) of neonatal seizures differ from those of children and adults. This study evaluated whether wavelet transform analysis, a nonstationary frequency analysis of EEG, can recognize and characterize neonatal seizures. Twenty-second segments were analyzed from 69 EEG seizures in 15 neonatal patients whose seizures lasted 10 seconds or longer. The wavelet transform results were examined, as were EEG seizure durations and dominant frequencies. The wavelet transform results were correlated with the occurrence, after an 18-month follow-up, of postneonatal seizures. Wavelet transform analysis identified 40 seizures (58%) with a “sustained dominant frequency component” that lasted 10 seconds or longer and 29 seizures without a sustained dominant frequency component. The mean seizure duration of the 40 seizures with sustained dominant frequency components was 63.3 seconds, longer than the mean duration (33.6 seconds) of the seizures without sustained dominant frequency components, P < 0.01. Eleven patients manifested postneonatal epileptic seizures. Fifty-two EEG seizures in these 11 patients revealed more sustained dominant frequency components (74%) than 17 seizures in the 4 patients without postneonatal seizures (only 12%), P < 0.05. Wavelet transform analysis can identify neonatal EEG seizures and characterize their epileptic components. The presence of sustained dominant frequency components may predict postneonatal epileptic seizures.Kitayama M, Otsubo H, Parvez S, Lodha A, Ying E, Parvez B, Ishii R, Mizuno-Matsumoto Y, Zoroofi RA, Snead OC III. Wavelet analysis for neonatal electroencephalographic seizures. [Copyright &y& Elsevier]

OBJECTIVE: To evaluate CyclinDI as a bio-marker for Squamous cell carcinoma and to see it's prognostic role in disease outcome. METHODOLOGY: This Descriptive cross-sectional study was conducted at section of Histopathology, Department of Pathology & Microbiology at Aga Khan University hospital from September 2016 till August 2017. Convenient sampling technique was used and 85 resection specimens (Paraffin Blocks) of invasive Squamous cell carcinoma of oropharynx of stage III & IV as per TNM classification were included in the study and Immunohistochemical staining for Cyclin D1was performed. Data analysis was done on SPSS version 19.0. Mean, standard deviation, frequencies and Chi square test were applied and p value less than or equal to 0.05 was taken as significant. RESULTS: More than 50% staining for Cyclin D1 was seen in 78.6%(n=67) of the cases while, 21.2% (n=18) samples showed < 50% staining. CONCLUSION: In conclusion, our results showed that cyclin D1 is overexpressed in majority of patients with oral SCC and is associated with aggressive clinicopathological features. [ABSTRACT FROM AUTHOR]

In this study, we investigate the reinforcing capability of multiwall carbon nanotubes (mwCNT) in alumina (Al 2 O 3) ceramic hybrid nanocomposites containing zirconium oxide nanoparticles (ZrO 2 np). For this purpose, highly dense hybrid nanocomposites containing well-dispersed ZrO 2 np (8 vol%) and mwCNT (4 vol%) were fabricated by the hot-pressing method. The resulting hybrid nanocomposite exhibited a ten-fold finer microstructure and 116% enhanced fracture toughness as well as 12% greater hardness over the benchmarked monolithic Al 2 O 3. The superior mechanical performance of the hybrid nanocomposite was attributed to the synergistic role of ZrO 2 np and mwCNT in refining the matrix microstructure and inducing unique toughening mechanisms of micro-cracking by ZrO 2 np and pull-out as well as crack-bridging by mwCNT. Qualitative and quantitative approaches were utilized to assess the individual and collective role of the reinforcing constituents in enhancing the performance of hybrid nanocomposite. The qualitative analysis by electron microscopes demonstrated strong interfacial adhesion of both reinforcing constituents with the based Al 2 O 3 matrix. Furthermore, the quantitative analysis verified that the enhanced mwCNT/Al 2 O 3 interfacial shear strength is caused by the intricate physical arrangement of the mwCNT within the matrix grains besides their chemical bonding at the interface. The role of fine-grained microstructure in establishing idiosyncratic mwCNT interlocking with the Al 2 O 3 matrix grains was meticulously investigated. Moreover, the influence of mwCNT/matrix interlocking on the mwCNT reinforcing ability and toughening mechanisms efficiency in the hybrid nanocomposite is discussed. • Al 2 O 3 /CNT/ZrO 2 hybrid nanocomposites were prepared by hot-pressing technique. • A 10 fold fine-grained microstructure was obtained for hybrid nanocomposites. • The hybrid nanocomposites showed 116% better fracture toughness over Al 2 O 3. • Reinforcing capability of the CNT in hybrid nanocomposite was gauged. [ABSTRACT FROM AUTHOR]

Mansehra district is prone to landslide because of climate conditions, geological and geomorphologic characteristics of the region. In October 2005, Kashmir earthquake triggered several thousand landslides in the Himalaya region of Northern Pakistan and India. In future, there are still great threats of further happening of such landslide events in this region. Therefore, it is very important to prepare detailed landslide susceptibility maps of the region helpful for any pre-emptive measures. In this study, the relationships between the landslides and various instability factors contributing to the occurrence of landslides were investigated using Remote Sensing and Geographical Information System (GIS) based approaches. For the preparation of landslide inventory maps slope, aspect, elevation, landuse/landcover, distance to stream, distance to road, distance to fault line, lithology, and soil types were used as raster layers in ArcGIS, and ranked using a numerical scale corresponding to the physical conditions of the area. In order to investigate the role of each instability factor in controlling the spatial distribution of landslides, Weighted Liner Combination Method was used. An index based approach is adopted both to put the various classes of all the parameters in order of their significance to the process of land sliding and weight the impact of on parameter against another. Using primary and secondary level weights, a contentious scale of numerical indices is obtained with which the study area is divided into different classes/zones of land sliding susceptibility from extremely low susceptible to very high susceptible classes. The results showed a strong relationship between the landslides occurrence and various instability factors. [ABSTRACT FROM AUTHOR]

The U.S. Environmental Protection Agency's "Four Lab Study" involved participation of researchers from four national Laboratories and Centers of the Office of Research and Development along with collaborators from the water industry and academia. The study evaluated toxicological effects of complex disinfection byproduct (DBP) mixtures,with an emphasis on reproductive and developmental effects that have been associated with DBP exposures in some human epidemiologic studies. This paper describes a new procedure for producing chlorinated drinking water concentrate for animal toxicology experiments, comprehensive identification of >100 DBPs, and quantification of 75 priority and regulated DBPs. In the research reported herein, complex mixtures of DBPs were produced by concentrating a natural source water with reverse osmosis membranes, followed by addition of bromide and treatment with chlorine. By concentrating natural organic matter in the source water first and disinfecting with chlorine afterward, DBPs (including volatiles sod semivolatiles) were formed and maintained in a water matrix suitable for animal studies. DBP levels in the chlorinated concentrate compared well to those from EPA's Information Collection Rule (ICR) and a nationwide study of priority unregulated DBPs when normalized by total organic carbon (TOC). DBPs were relatively stable over the course of the animal studies (125 days) with multiple chlorination events (every 5-14 days), and a significant portion of total organic halogen was accounted for through a comprehensive identification approach. DBPs quantified included regulated DBPs, priority unregulated DBPs, and additional DBPs targeted by the ICR. Many DBPs are reported for the first time, including previously undetected and unreported haloacids and hatoamides. The new concentration procedure not only produced a concentrated drinking water suitable for animal experiments, but also provided a greater TOC concentration factor (136x), enhancing the detection of trace DBPs that are often below detection using conventional approaches. [ABSTRACT FROM AUTHOR]

Manganese oxide (MnO x) is a low cost and environment-friendly electrode material for supercapacitors. Although most efforts have been devoted to increase the surface area of this material, the role of surface defects in different MnO x polymorphs towards improvement of its capacitance remains to be thoroughly investigated. In this paper, the results from electrodeposition of mesoporous MnO x thin film electrodes and the effect of rapid thermal annealing (RTA) on their electrochemical storage behavior are presented and discussed. X-ray photoelectron spectroscopy (XPS) analyses showed an increase of the Mn2+/Mn3+ ratio as well as hydroxyl group defects on the surface of the annealed electrodes. The as-deposited MnO x did not manifest any capacitance behavior in 1.0 M Na 2 SO 4 electrolyte solution. However, after RTA treatment, the specific capacitance was tremendously enhanced. An areal capacitance as high as 110 mF cm−2 at 5 mV s−1 was recorded in 1.0 M Na 2 SO 4 electrolyte with a capacitance retention of 74% after 5000 charge-discharge cycles. Furthermore, the RTA treatment of electrodes significantly decreased the charge transfer resistance value from 0.678 × 106 Ω for the pristine MnO x electrode to 39.13 Ω for the treated one. Based on structural and surface chemistry evolution of the MnO 2 films after annealing, the electrochemical storage behavior of annealed MnO x is discussed. Image 1 • Electrodeposited mesoporous MnO 2 films were treated for rapid thermal annealing. • XPS analysis confirmed Mn2+/Mn3+ increase besides hydroxyl groups attachment. • RTA treatment decreased the charge transfer resistance from 0.678 MΩ to 39.13 Ω. • EIS indicated excellent pseudocapacitive behavior due to large electroactive area. • High areal capacitance and cyclic stability up to 5000 cycles were achieved. [ABSTRACT FROM AUTHOR]