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Summary Objective Maximum phonation time (MPT) is a test to measure glottic efficiency for laryngeal pathology screening and treatment monitoring. The normative value of MPT for South East Asia population has yet to be reported. It is postulated that MPT may be affected by body mass index (BMI) despite the paucity of evidence. Therefore, this study was designed to establish the normative value of MPT for a South East Asia population and investigate its relation to BMI. Design & Setting This cross-sectional study was conducted in Universiti Kebangsaan Malaysia Medical Center between May and September 2017. Participants and Methods Three hundred males and females with mean age of 30.23 (±11.04) years were recruited in equal number for each gender (n = 150) and divided into 3 groups of 50 according to their BMI (n = 50). The three groups are non-obese (BMI≤22.9kg/m2); obese (BMI between 23 and 34.9 kg/m2); and morbidly obese (BMI >35kg/m2). BMI and Voice Handicap Index-10 (VHI-10) were obtained. The average of three readings of MPT was measured using a stopwatch while the participants phonate /a/, /i/ and /u/. Unpaired t-test and ANOVA were used to compare means between and across groups. Spearman correlation assessed the correlation between MPT and BMI. Main outcome measures The normative values of MPT of both genders and correlation with BMI were analyzed. Results The MPT normative values for males and females in the non-obese group were of 21.41 (±6.85) seconds and 18.05 (±5.06)seconds respectively for /a/. The MPT for all vowels were significantly higher in males across the BMI groups (P ≤ 0.05). There was low negative correlation between MPT and BMI in both genders. Conclusions This pioneering study documented the normative values of MPT among Malaysians showed that males had longer MPT than females across the BMI groups. Obesity affects the MPT in that as BMI increases, the MPT decreases.

Graphical abstract, Highlights • Generation of hydroxyl radical (·OH) increased by proflavine upon illumination with fluorescent light. • Proflavine resulted in oxidative modifications and degradation of protein and enzyme structure. • The addition of Cu (II) augmented photo-illuminated proflavine to generate hydroxyl radicals. • Proflavine-induced hydroxyl radicals have a deleterious influence on protein and enzyme activity., Proflavine is a well-known antiseptic and bacteriostatic drug, however, it has the potential to be hazardous and mutagenic. Proflavine enters cells and intercalates between DNA base pairs, resulting in mutation and replication inhibition. Previously several investigators demonstrated that photo-activated proflavine generated double-stranded DNA breakage and protein structural alterations. The present study investigated the role of hydroxyl radical (·OH) due to activation of proflavine in the breakdown of protein and enzyme by photo-activated proflavine. The results show that the formation of hydroxyl radicals increased as the photo-illumination period increased, as did the concentrations of proflavine and Cu (II). As demonstrated by SDS-PAGE, the excess of free radicals due to proflavine resulted in oxidative modifications and degradation of BSA protein and trypsin enzyme. Additionally, with an increase in Cu (II) concentration, photo-illuminated proflavine induced a considerable loss of enzyme activity and also accelerated the degradation of the enzyme. Bathocuproine, a particular Cu (I)-sequestering agent, prevented protein degradation and enzyme inactivation. Hydroxyl radical scavengers inhibited the protein-damaging process, indicating that hydroxyl radicals play a substantial role in protein damage. The tryptophan moiety was quenched by proflavine, demonstrating that it binds to proteins and enzymes, changing their structure and activity. As a result, this study helps to better understand proflavine's deleterious influence on protein and enzyme degradation by oxygen-free radicals.

The military and aerospace industries require lightweight and high stiffness materials, which can reduce the CO2 emission and total cost of the project. Magnesium alloys are one of the best replacements of heavy-weight materials and can be employed to withstand the high strain rate shock wave impact under stringent environments. The resistance against shock wave impact can be endured by the plastic deformation, therefore, understanding the complex deformation behavior of magnesium alloys and temperature rise under high strain rate impact is necessary, especially, adiabatic shear band development which leads to early failure. So, this article emphasizes the shapes of stress–strain curves (sigmoidal shape and concave down shape) and the deformation behaviors of high strain rate compressed magnesium alloys under different temperatures and further its correlation with the ballistic impact. The prediction of temperature rise and strain rate away from the crater is a big dilemma owing to the very short interval of ballistic impact. Here, based on Wright criterion and microstructure evolution of dynamically compressed alloys with the microstructure of ballistic impacted magnesium alloys, the temperature rise in adiabatic shear bands and away from the carter was evaluated. In the end, some suggestion has been proposed for increasing the efficiency of the magnesium alloys during high strain rate compression/ballistic impact.

Foam-assisted gas has been widely employed in enhanced oil recovery (EOR) by improving the volumetric sweep efficiency gas mobility of injected gas. However, the major obstacle of foam-assisted gas EOR is maintaining foam lamellae’s stability, especially in harsh reservoir conditions. As mentioned above, the study focused on the effect of silica nanoparticles (SiO2 NPs) in an anionic/nonionic surfactant mixture in enhancing the stability of foam film. The optimum concentration of silica nanoparticles was determined through various experimental approaches. The surface tension and interfacial tension in the presence and absence of SiO2 NPs were measured and recorded. The Bartsch shaking method was applied to analyse the foam half-life and foam static stability. Anionic surfactant Sodium Dodecyl Sulfate (SDS) was utilised with the nonionic surfactant Triton X100 (TX100) at a ratio of 4:1. Addition of various concentration (0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt% and 1.0 wt%) SiO2 NPs in two surfactant mixtures. The screening method was utilised to determine the optimum concentration of SiO2 NPs in SDS-TX100 surfactant mixture at 25 °C and 70 °C. The optimisation from the screening process demonstrated 0.4 wt% SiO2 NPs was suitable in SDS-TX100 surfactant mixture for stabilising the foam films.

Technologies that utilize natural renewable resources and rely on no fuels are more sustainable and could, in part, solve the world's current water and energy problems. The aim of this study is to fabricate and develop a single solar still that is directly connected with a solar parabolic trough and does not utilize any heat exchanger. An innovative feeding water tank was installed with the parabolic unit. Fieldworks and manufacturing, laboratory experiments, and water quality analysis were the tools used in this study. The results of the field experiments demonstrated that the overall water productivity of the modified solar still increased by 177% compared to the conventional still. The average hourly quantity of freshwater obtained from the modified and unmodified models of the solar still were 0.67 L/m2/hr and 0.38 L/m2/hr, respectively. Building on these results, this study also proposed the future investigation of a step-shaped conical unit for the same device, which appears more promising and easier to handle, install, and maintain. This study showed feasible and viable results and verifies the importance of technologies that rely on renewable resources to achieve secure and sustainable management of the world's water and energy needs.

From the mechanistic point of view, magnesium alloys are lightweight materials and are receiving increasing attention in the past several years in various fields. Prof. Liang Zhen from Harbin Institute of Technology, China and the United State military are showing keen interest in the development of magnesium alloys as ballistic resistant material. However, their use is still limited owing to low ductility, low formability, and average mechanical properties. The magnesium alloys components must withstand the shockwave under hypervelocity ballistic impact. The ballistic testing can produce gradient variations of the strain and stress-energy away from the crater, and useful for the development of these alloys in the military and aerospace industry. Therefore, the present review article shed light on the post deformation analysis of the Mg alloys subjected to the different projectiles under ballistic impact, and the underlying mechanisms were discussed. In the end, some important issues regarding the ballistic impact and further studies in this field were proposed.

Graphene ferrites have attracted great attention due to their high conductivity and large specific area. Now, the modern age demands some new materials which have a low weight, less cost and have great mechanical strength. Graphene is the best suggestion to meet this criteria. Here, graphene oxide (GO) was synthesized with Hummer's method. Prussian Blue (PB) and Fe3O4 nanoparticles were doped in graphene oxide with the Massart method. XRD spectra were used to analyze the structural properties. Peaks of XRD spectra at 2θ = 24.16°, 30.01°, 35.27°, 39.29°, 43.37°,53.82°, and 57.14° confirmed the formation of PB and Fe3O4 nanoparticles in graphene oxide. Electronic transition properties were studied through UV–visible spectroscopy and a peak of π to π* transition is detected at 198.9 nm in PBGOF. Due to charge transformation between carbon network, magnetite and PB, the strong shifted peak is detected in PBGOF in PL spectra at 439.2 nm. At lower frequency the dielectric properties exhibit higher values of permittivity and vary as a function of frequency. Electrical properties investigated through impedance spectroscopy and material show increment in electrical behavior. AC resistivity exhibit the small resistance and high conductive properties of the material with the increase of frequency. There is an expectation that with the introduction of magnetite in Graphene, the dielectric properties enhanced dramatically. Our finding revealed that our material has many possible applications in electrical and electronic devices etc.

Objective Deep brain stimulation (DBS) has been used as a treatment of last resort for treatment-resistant depression (TRD) for more than a decade. Many DBS targets have been proposed and tested clinically, but the underlying circuit mechanisms remain unclear. Uncovering white matter tracts (WMT) activated by DBS targets may provide crucial information about the circuit substrates mediating DBS efficacy in ameliorating TRD. Methods We performed probabilistic tractography using diffusion magnetic resonance imaging datas from 100 healthy volunteers in Human Connectome Project datasets to analyze the structural connectivity patterns of stimulation targeting currently-used DBS target for TRD. We generated mean and binary fiber distribution maps and calculated the numbers of WMT streamlines in the dataset. Results Probabilistic tracking results revealed that activation of distinct DBS targets demonstrated modulation of overlapping but considerably distinct pathways. DBS targets were categorized into 4 groups: Cortical, Striatal, Thalamic, and Medial Forebrain Bundle according to their main modulated WMT and brain areas. Our data also revealed that Brodmann area 10 and amygdala are hub structures that are associated with all DBS targets. Conclusions Our results together suggest that the distinct mechanism of DBS targets implies individualized target selection and formulation in the future of DBS treatment for TRD. The modulation of Brodmann area 10 and amygdala may be critical for the efficacy of DBS-mediated treatment of TRD.

Using household data from the latest wave of the Ghana Living Standards Survey, this paper utilizes machine learning techniques – IV LASSO – that allows for the treatment of unconfoundedness in the selection of observables and unobservables to examine the structural effect of gender wage differences within households on women's empowerment and welfare in Ghana. The structural parameters of the IV LASSO estimations show that a reduction in household gender wage gap significantly enhances women's empowerment. Also, a decline in household gender wage gap results meaningfully in improving household and women's welfare. Particularly, the increasing effect on women's welfare resulting from decreases in household gender wage differences is much higher than for the household welfare. The findings showcase the need to vigorously adopt policies that both increase the quantity and quality of jobs for women and address gender barriers that inhibit women from accessing these jobs opportunities in sub-Saharan Africa.

In this paper, we present a general framework to estimate the network entropy that is represented by means of an undirected graph and subsequently employ this framework for graph classification tasks. The proposed framework is based on local information functionals which are defined using induced connected subgraphs of different sizes. These induced subgraphs are termed graphlets. Specifically, we extract the set of all graphlets of a specific sizes and compute the graph entropy using our proposed framework. To classify the network into different categories, we construct a feature vector whose components are obtained by computing entropies of different graphlet sizes. We apply the proposed framework to two different tasks, namely view-based object recognition and biomedical datasets with binary outcomes classification. Finally, we report and compare the classification accuracies of the proposed method and compare against some of the state-of-the-art methods.

The study aimed to shed light on the post deformation and damage behavior of an extruded Mg-Zn-Zr alloy under a ballistic impact. The results revealed that the initial microstructure consisted of both 0001 basal and 10 1 0 prismatic fiber texture. After impact, adiabatic shear bands, pronounce different twinning in big grains, , , and types of dislocations, and grain refinement through twinning induce recrystallization accommodated the strain, and absorbed ∼65.7 % of the energy during impact carried by a soft steel projectile. Interestingly, the deformation behavior at the top broad sides of the crater was entirely different. The weak basal texture was changed to a strong prismatic texture, which was further proved by typical sigmoidal compressive stress-strain curves. A revised model for the development of the ultra-fine grains adjacent to the crater has been proposed. The microhardness and yield strength was ∼33 % and ∼40 % higher and chiefly ascribed to strain hardening in ultra-fine grained near the surface of the perforation path. The exit of the perforation path was severely damaged and forms onion-shaped concentric rings which were comprised of melted zones, dimples, and cracks. Based on the all interesting findings, this study can be a clue for the development of the lightweight Mg alloy for military and aerospace applications.

Carbon based materials have attracted much attention due to their high conductivity and shielding properties. In the present investigation, Fe4[Fe(CN)6]3 (Prussian blue), graphene oxide (GO) and magnetite (Fe3O4) nanocomposite was prepared and their electromagnetic (EM) shielding efficiency was evaluated. The GO was prepared via Hummer's method and composite was prepared with Fe3O4 and Fe4[Fe(CN)6]3. The prepared composite was characterized by X-ray diffraction (XRD), photoluminescence (PL), Fourier transform infrared (FTIR), ultraviolet visible (UV–Vis) and Raman spectroscopy techniques. The average particle size of Fe4[Fe(CN)6]3/GO/Fe3O4 (PBGF) composite was 13.19 nm with density of 0.943 g/cm3, Using dielectric parameters, the shielding effectiveness of the sample was evaluated. A −51.66 dB of reflection losses was observed at 2 MHz and results revealed that the PBGF has manifesting properties of shielding absorbance which are useful for EMI shielding application.

The effect of NiO-m-BCZY64 (BCZY64 = BaCe0.54Zr0.36Y0.1O2.95) as a composite anode with a single anode functional layer (AFL) and gradient AFL on the performance of a button cell was systematically evaluated. The m-BCZY64 is referred to the pristine BCZY64 that was modified by a functionalized activated carbon derived from palm-oil empty fruit bunch (EFB). The electrochemical performance of the cell was investigated by impedance spectroscopy in a controlled atmosphere. The NiO-m-BCZY64 exhibited smaller grain size and homogenous elemental distribution compared to pristine NiO-BCZY64 as observed by SEM/EDX. At T = 800 °C, a button cell consists of NiO:m-BCZY64 with gradient AFL showed the best performance with total resistance (RT) of 21.12 Ωcm2 compared to the cell with single AFL (RT = 86.04 Ωcm2) and pristine NiO-BCZY64 (RT = 145.64 Ωcm2). The significant reduction of RT indicates that the NiO:m-BCZY64 with gradient AFL showed high potential to be used as a composite anode for proton-conducting solid oxide fuel cells.