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Despite the prevalent application of 18% Ni maraging steel in critical sectors such as aerospace and automotive due to its unique characteristics, including high ductility, yield strength, and hardenability, its machining presents enormous challenges, categorizing it as a difficult-to-machine material. The cutting tool's geometry is crucial in machining, significantly affecting chip formation, cutting forces, power consumption, and obtainable surface quality. In particular, wiper insert technology, characterized by its multi-radius design, offers an increased contact area compared to conventional inserts, potentially enhancing the quality of the machined surface. This study explores the effectiveness of wiper inserts in the face-milling of maraging steel 350, conducting a comparative analysis across three distinct machining setups. These setups vary by alternating the number of wiper and conventional inserts within the same cutter, thereby examining the influence of insert configuration on machining outcomes. The research employs a reliable and well-established statistical approach to evaluate how different variables, such as cutting speed and feed rate, affect surface quality, power consumption, and material removal rate (MRR). It also sheds light on the material removal mechanisms facilitated by each type of insert. The findings reveal that incorporating a higher number of wiper inserts significantly enhances the surface finish but concurrently increases power consumption. Thus, the study successfully identifies an optimal set of process parameters that attain a balance between achieving superior surface quality and maintaining energy efficiency in the machining of maraging steel 350. This balance is crucial for optimizing manufacturing processes while adhering to the stringent quality and sustainability standards required in aerospace and automotive manufacturing. [ABSTRACT FROM AUTHOR]

A novel controller based on multiresolution decomposition using wavelets is presented. The controller is similar to a proportional-integral-derivative (PID) 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. Index Terms--Motion control, multiresolution, wavelet controller, wavelets.

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]

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]

This paper presents a three-dimensional simulation of stationary gas tungsten arc welding which studies the development of the arc and weld pool in three types of joints, namely L-shape, V-shape and open-corner. Temperature, heat flux, current density and gas shear stress are determined in the arc and are used as input to the workpiece to determine the heat, fluid flow and weld pool shape. Buoyancy and surface tension gradient which affect the pool shape are taken into consideration. It is observed that the current density, heat flux and gas shear distribution in the arc domain is the same in all the cases. The electromagnetic force is observed to be the same in L-shape and V-shape joints. In the case of the open-corner joint, some electromagnetic force is also observed on the bottom edge of the weld. The fluid flow and weld pool shape is found to be the same in the case of L-shape and V-shape joints which shows that the orientation of workpiece does not produce any gravity effect. Due to the sharp edge in the open-corner joint, the weld pool is observed to be shallow and wide. In all three cases, the molten metal flows from the sides and the weld pool is formed slightly upwards at the weld centre in the experimental results. This phenomenon is not considered in the numerical analysis and the weld pool depth near the weld centre is a little different from the experimental results; however, the remaining pool shapes are observed to be in good agreement. [ABSTRACT FROM AUTHOR]

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: 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]

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]

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]

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]

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]