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Alginate and gellan gum have both been used by researchers as reinforcing networks to create tough and biocompatible polyethylene glycol (PEG) based double network (DN) hydrogels; however, the relative advantages and disadvantages of each approach are not understood. This study directly compares the mechanical and biological properties of polyethylene glycol di-methacrylate (PEGDMA) hybrid DN hydrogels reinforced with either gellan gum or sodium alginate using PEGDMA concentrations from 10 to 20 wt% and reinforcing network concentrations of 1 and 2 wt%. The findings demonstrate that gellan gum reinforcement is more effective at increasing the strength, stiffness, and toughness of PEGDMA DN hydrogels. In contrast, alginate reinforcement yields DN hydrogels with greater stretchability compared to gellan gum reinforced PEGDMA. Furthermore, separate measurements of toughness via unnotched work of rupture testing and notched fracture toughness testing showed a strong correlation of these two properties for a single reinforcing network type, but not across the two types of reinforcing networks. This suggests that additional notched fracture toughness experiments are important for understanding the full mechanical response when comparing different tough DN hydrogel systems. Regarding the biological response, after conjugation of matrix protein to the surface of both materials robust cell attachment and spreading was supported with higher yes associated protein (YAP) nuclear expression observed in populations adhering to the stiffer gellan gum-PEGDMA material. This study provides valuable insights regarding how to design double network hydrogels for specific property requirements, e.g., for use in biomedical devices, as scaffolding for tissue engineering, or in soft robotic applications. [ABSTRACT FROM AUTHOR]

Anticipating an increasing demand for hybrid double network (DN) hydrogels in biomedicine and biotechnology, this study evaluated the effects of each network on the mechanical and biological properties. Polyethylene glycol (PEG) (meth)acrylate hydrogels with varied monomer molecular weights and architectures (linear vs. 4-arm) were produced with and without an added ionically bonded alginate network and their mechanical properties were characterized using compression testing. The results showed that while some mechanical properties of PEG single network (SN) hydrogels decreased or changed negligibly with increasing molecular weight, the compressive modulus, strength, strain to failure, and toughness of DN hydrogels all significantly increased with increased PEG monomer molecular weight. At a fixed molecular weight (10 kDa), 4-arm PEG SN hydrogels exhibited better overall mechanical performance; however, this benefit was diminished for the corresponding DN hydrogels with comparable strength and toughness and lower strain to failure for the 4-arm case. Regardless of the PEG monomer structure, the alginate network made a relatively larger contribution to the overall DN mechanical properties when the covalent PEG network was looser with a larger mesh size (e.g., for larger monomer molecular weight and/or linear architecture) which presumably enabled more ionic crosslinking. Considering the biological performance, adipose derived stem cell cultures demonstrated monotonically increasing cell area and Yes-associated protein related mechanosensing with increasing amounts of alginate from 0 to 2 wt.%, demonstrating the possibility for using DN hydrogels in guiding musculoskeletal differentiation. These findings will be useful to design suitable hydrogels with controllable mechanical and biological properties for mechanically demanding applications. Hydrogels are widely used in commercial applications, and recently developed hybrid double network hydrogels have enhanced strength and toughness that will enable further expansion into more mechanically demanding applications (e.g., medical implants, etc.). The significance of this work is that it uncovers some key principles regarding monomer molecular weight, architecture, and concentration for developing strong and tough hybrid double network hydrogels that would not be predicted from their single network counterparts or a linear combination of the two networks. Additionally, novel insight is given into the biological performance of hybrid double network hydrogels in the presence of adipose derived stem cell cultures which suggests new scope for using double network hydrogels in guiding musculoskeletal differentiation. [Display omitted] [ABSTRACT FROM AUTHOR]

• FEA study examined the interaction between perpendicularly crossing twin tunnels. • The study focused on transverse & longitudinal settlement induced by the tunnels. • Development of settlement at various stages of tunnelling were investigated. • The effect of geometric parameters on the induced soil settlement was explored. A series of three-dimensional parametric finite element analyses were carried out to investigate the induced ground surface settlement during the excavation of perpendicularly under and above crossing twin tunnels. Both transverse and longitudinal settlements are investigated and presented in this study. The results suggest that the larger the cover depth, the wider the transverse settlement trough and the more the position of maximum settlement shifted towards the existing tunnel centerline. It is also evident that the lower the cover depth the higher the settlement increase rate is. Other important findings are (i) both transverse and longitudinal tunnel displacements increase with an increase in the pillar distances when the upper tunnel is excavated first and vice-versa, and (ii) the maximum transverse settlement occurs at the centerline of the existing tunnel whereas the maximum longitudinal settlement occurs at and around the excavation face. Furthermore, the effect of various stages of the crossing tunnel excavation and tunnel sizes are also examined, and it is observed that the transverse settlement trough becomes wider and deeper as the new undercrossing tunnel advances away from the existing upper tunnel. It is also found that as the diameter of a tunnel increases, the transverse settlement of both the existing tunnel and the newly excavated crossing tunnel increases regardless of the excavation sequence. [ABSTRACT FROM AUTHOR]

This study aims to examine the effect of audit committee social capital, measured using network centrality from social network theory, on the adoption of the COSO 2013 updated internal control framework (COSO 2013). Drawing on social capital literature, we argue that well-connected audit committees have informational advantages and reputational concerns which prompt them to learn more about best industry practices and adopt those practices in their own organizations. As predicted, we find organizations that have well-connected audit committees are more likely to adopt COSO 2013 and do so in a timely manner. Additional analysis indicates that our findings are driven by overall audit committee connectedness and not by the connectedness of committee chairs, committee financial experts, or committee members, and hold only for accelerated filers. Further, we find, contrary to conventional wisdom, that audit committee connectedness prompts KPMG client organizations to adopt COSO 2013. The results hold even after controlling for CEO and CFO connectedness and are robust to endogeneity concerns. By linking audit committee connectedness with COSO 2013 adoption, we add to the literature investigating the effect of audit committee characteristics on firm compliance with internal control framework updates. [ABSTRACT FROM AUTHOR]

Optimal PV based EV charging is performed either by predicting or by measuring PV output. However, due to the uncertainties associated with the variables involved, both the charging methods are not only disposed to significant voltage limit violations but also may cause PV energy harvest reduction. Hence, a methodology is proposed in this paper, which utilizes the measured PV output of a given sample and the supplied historical ramp to predict the PV output of the immediate next sample using a non-iterative method. The charging rates of the EV population are, subsequently, adjusted in the interval between the successive samples based on the predicted PV output with the help of a proposed SOC based charging strategy. The proposed methodology has been tested at the University of Queensland (UQ)’s solar and parking facilities coupled with its electric grid. The results show that aside from reducing the probability of voltage limit violations (PVV), the proposed methodology can increase the PV energy harvest. Moreover, it is cost-effective as compared to the conventional method such as onsite battery energy storage deployment. [ABSTRACT FROM AUTHOR]

Chitosan/PVA/Na–titanate/TiO 2 composite was synthesized by solution casting method. The composite was analyzed via Fourier Transform Infrared Spectroscopy, X-ray diffraction, Field Emission Scanning Electron Microscopy, Thermal gravimetric analysis and water stability test. Incorporation of Na-titanate shown decrease of crystallinity for chitosan but increase water stability. However, the composite structure was deteriorated with considerable weight loss in acidic medium. Two anionic dyes, methyl orange and congo red were used for the adsorption test. The adsorption behavior of the composites were described by pseudo-second-order kinetic model and Lagergren-first-order model for methyl orange and congo red, respectively. For methyl orange, adsorption was started with a promising decolorization rate. 99.9% of methyl orange dye was removed by the composite having higher weightage of chitosan and crystalline TiO 2 phase. On the other hand, for the congo red the composite having higher chitosan and Na-titanate showed an efficient removal capacity of 95.76%. UV–vis results showed that the molecular backbone of methyl orange and congo red was almost destroyed when equilibrium was obtained, and the decolorization rate was reaching 100%. Kinetic study results showed that the photocatalytic degradation of methyl orange and congo red could be explained by Langmuir–Hinshelwood model. Thus, chitosan/PVA/Na–titanate/TiO 2 possesses efficient adsorptivity and photocatalytic property for dye degradation. [ABSTRACT FROM AUTHOR]

In this work, two types of sandwich structures were fabricated to develop sustainable building materials using renewable and waste resources. The chopped jute fiber reinforced perlite-filled gypsum composite was used as the core and the brown paper and the woven jute fiber reinforced epoxy composite (JFRC) were used as skins to manufacture the sandwiches. The effect of jute fiber content (10 g - 20 g) in the core on the flexural properties was studied. The flexural test was conducted to determine the flexural strength, modulus, energy absorption, and the load-bearing capacity of brown paper skin-based sandwiches (BPSS) and JFRC skin-based sandwiches (JFSS). The results of this study show that the flexural properties of both BPSSs and JFSSs are improved significantly with increasing jute fiber content up to 17.5 g indicating the optimum fiber content. The flexural strength and modulus of BPSS at 17.5 g jute fiber content are respectively 8.44 % and 30.16 % greater than those at 10 g jute fiber content. On the other hand, the JFSSs show 30.24 % and 60.36 % increase in flexural strength and modulus respectively at 17.5 g jute fiber content compared to those at 10 g fiber content. The flexural energy absorptions of BPSS and JFSS are also increased by 45.40 % and 22.90 % respectively when jute fiber content in the core is increased from 10 g to 17.5 g. The specific load-bearing capacity of JFSSs is 130.38 % - 216.56 % greater than BPSSs depending on the fiber content in the core. [Display omitted] • Two types of sandwich structures were developed using gypsum/perlite composite core. • Flexural properties of sandwiches increased with increasing jute fiber content. • The optimum jute fiber content in gypsum/perlite composite core is 17.5 g (4.22 %). • JFRC skins significantly improved the specific load bearing capacity and toughness. • Distinct failure mechanisms observed for BPSSs and JFSSs. [ABSTRACT FROM AUTHOR]

Tensor based methods have gained popularity for being able to represent multi-aspect real world data in a lower dimensional space. Among them, methods with orthogonal factors perform relatively better in classification. However, most of them cannot handle higher order data. Recently, Tensor Ring (TR) based methods are proposed to combat with the higher order issue more effectively focusing on both classification and reconstruction. A TR-based method with orthogonal cores performs reasonably well for a given error. However, its computational complexity is very high and might produce extra features. To solve these issues, in this paper, we propose a method named as Orthogonal basis-core extraction using Tensor Ring (OTR) that can facilitate better discrimination and reconstruction at a lower cost. To maintain the ring property, we also show, theoretically, that reshaping of the product of semi-orthogonal reshaped cores remains semi-orthogonal. Rigorous experiments over eighteen benchmark datasets from different fields demonstrate the superiority of OTR over state-of-the-art methods in terms of classification and reconstruction. • Orthogonal basis-core extraction using Tensor Ring (OTR) can deal with higher order. • It produces semi-orthogonal basis-cores at a lower cost. • We proof that the basis-cores and their circular products are semi-orthogonal. • OTR captures discriminative information reasonably well in a fewer number of steps. • Basis-cores obtained using OTR can be used for reconstruction of the original tensor. [ABSTRACT FROM AUTHOR]

Gypsum wallboards are widely used as a building material, but limitations exist in their weight and brittleness. The incorporation of various fillers in the gypsum makes them lightweight, stiff, and capable of resisting catastrophic failure but with the cost of strength. Sandwiching the filled gypsum using a low-cost material as skin may be an innovative approach to improve the flexural properties. In this work, sandwich structures were fabricated using jute fiber reinforced and unreinforced perlite-filled gypsum as cores and low-cost brown paper as skins. The density, flexural strength, modulus, and toughness of the resulting sandwich structures were investigated. It is found that the increase in perlite content in pure gypsum and jute fiber-reinforced gypsum significantly enhances the flexural strength, modulus, and toughness of the sandwich structures. However, previous research on jute fiber-reinforced and unreinforced gypsum/perlite composite panels (without skin) showed a decrease in flexural strength due to an increase in perlite content. The maximum flexural strengths of unreinforced sandwich (URS) and jute fiber reinforced sandwiches (JRS) at a perlite content of 15 g are found to be 13.29 % and 40.79 % greater than the control sandwich with pure gypsum core. The maximum flexural toughness of the JRS at a perlite content of 20 g and that of the URS at a perlite content of 15 g are respectively 118.31 % and 79.14 % greater than the control sandwich. A significant difference in load-displacement curves between JRSs and URSs is noticed despite the similar failure sequence i.e. core cracking→skin yielding→skin tearing. [Display omitted] • Sandwich structures were fabricated using gypsum/perlite composite and paper skin. • Flexural strength increased due to the addition of perlite & jute fiber in the core. • The optimum perlite contents in URS and JRS cores are 3.53 % and 3.61 % respectively. • Flexural strength and toughness of JRSs are greater than those of URSs. • URSs and JRSs showed unique load-deflection curves despite identical failure modes. [ABSTRACT FROM AUTHOR]

• A review of twin tunnelling induced ground settlement is presented. • Side-by-side, piggyback, perpendicular, and offset tunnelling arrangements examined. • Field observations, laboratory tests, and finite element analyses summarized and compared. • Effects of construction sequence, pillar width, and cover depth are presented. In the past few decades, the number of tunnels constructed next to an existing tunnel has been gradually increasing in order to accommodate infrastructure needs in congested urban cities. When a new tunnel is constructed adjacent to an existing tunnel, both the relative position of the tunnels and the construction sequence affect the ground settlement and internal forces in the linings of both tunnels. Therefore, it is important to study the influence of these factors and their relationship to tunnel construction. A review of twin tunnelling induced ground settlement is presented in this paper. A wide range of data is collected, summarized, and compared with each other to infer interaction phenomenon related to ground settlement. This data is gathered from published field observations, laboratory tests, and finite element analyses. The paper begins with an overview of single tunnelling induced settlements, volume losses, and factors which can affect twin tunnelling induced ground settlements. Next, a summary of the effects of construction sequence, pillar width, and cover depth, among other influencing factors, has been presented for four twin tunnelling configurations including (i) side-by-side, (ii) piggyback, (iii) perpendicularly crossing, and (iv) offset arrangement twin tunnelling. The paper also presents a summary of available techniques to calculate ground settlements induced by a new tunnel excavation in the presence of an existing tunnel. Finally, the paper summarizes available knowledge on ground settlement induced by various twin tunneling arrangements and identifies known unknowns. [ABSTRACT FROM AUTHOR]

Background In developing countries global incidence of breast and cervical cancer is rising and the increase is occurring at a faster rate. Cancer is the sixth leading cause of death in Bangladesh. Objective: To investigate the awareness of early detection method, symptoms and risk factors towards breast and cervical cancer screening amongst young adult female students in Bangladesh. Methods: A total of 1004 adult female students at the age of (18 - 26) years were randomly included in the study using a multistage cluster sampling technique. A questionnaire included socio-demographic characteristics and information related to their knowledge about breast and cervical cancer. Results: The results showed that about 61.3% participants were Undergraduate. Among them only 37.5% respondents aware about breast cancer risk; 25.7% aware about the detection method of breast cancer and only 21.1% have knowledge about cervical cancer risk factors. About 87.4% respondents have not any family history of cancer; 3.5% participants have sister or mother having breast tumor and 22.1% have at least more than one close relative who have cancer. Among the participants, only 2.5% drank alcohol; 24.7% girls wear tight bra; 4.1% have benign breast diseases. Participants with better knowledge score were 8.1% times more likely to practice BSE; only 6.3% were examined by clinically breast examination. Conclusion: It can be concluded that, knowledge of participants regarding breast and cervical cancer is very poor. Broad based study in large population with sound methodology is required to find out real situation about this matter in Bangladesh. [ABSTRACT FROM AUTHOR]

Background The literature on breast and cervical cancer treatment in Bangladesh is nonexistent. There are significant challenges to the development of infrastructure for cancer care in Bangladesh. Methodology: This cross-sectional study was conducted at Jahurul Islam Medical College and Hospital, Bangladesh. Among 685 participants of the survey, 379 respondents were medical students at the age of 18 to 26 years and rest of the participants (306 patients of the hospital) were randomly included in the study using a multistage cluster sampling technique. The IBM SPSS statistics (V21.0) software was used to analyze survey data. Results: The results of the survey indicates that the majority of medical students are familiar with the early detection methods of breast cancer. However, the students were not aware of the risk factors of cervical cancer including HIV infection (27.2%) and the long-term use of contraceptive pill (22.7%). The students also are not going through the regular smear or Pap test (28.0%) or not aware of infection from HPV (16.6%). Only a few students are aware of the risk of breast cancer including Hormone replacement therapy (3.2%) and Benign breast disease (5.5%). On the other hand, the randomly selected patients of the hospital (100%) have no idea about the risk factors of breast and cervical cancer. As a result, they have no knowledge about the early detection methods of breast cancer. Conclusion The summary of this study indicates that the medical students and patients of the hospital are not sufficiently aware of the sign symptoms, risk factors, and preventive measures for breast and cervical cancer. Therefore, necessary steps are very crucial to grow awareness among the general people of Bangladesh from the respective authority to be careful about breast cancer and cervical cancer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gypsum composites with expanded perlite and jute fiber were manufactured. • The incorporation of perlite and jute fiber in gypsum is a mixed blessing. • Expanded perlite filler decreased the strength but specific strength was increased. • Jute fiber reinforcement increased the toughness of the composites significantly. • Failure mechanisms during compression and flexural tests were positively changed. In this work, jute fiber reinforced gypsum composites (JRGCs) and unreinforced gypsum composites (URGCs) using varying amounts of expanded perlite particles as filler were manufactured to investigate the effects of perlite content and fiber reinforcement on the mechanical properties of the composites. The prepared composites were characterized for density, compressive properties, flexural properties, and failure behaviour during both compression and flexural tests. The incorporation of perlite and jute fibers in gypsum showed both positive and negative impacts on the mechanical properties. The addition of expanded perlite in pure gypsum improved the density, specific compressive strength, compressive modulus, and compressive toughness. The flexural modulus and toughness were enhanced remarkably for both JRGCs and URGCs due to the addition of perlite although the flexural strength was decreased. The compressive and flexural toughness were increased by 140.73 % and 3608.03 % respectively due to 2.44 % jute fiber reinforcement in the pure gypsum although the compressive and flexural strength were decreased by 12.79 % and 13.94 % respectively. The failure mechanisms during compression and flexural tests were positively changed and the crack propagation after failure initiation was successfully arrested by jute fiber reinforcement. [ABSTRACT FROM AUTHOR]

• Conjugase treatment was sufficient for soybean folate extraction. • 10-fold variation was observed for soybean folates, from 64.51 − 691.24 μg/100 g. • 5-CHO-H 4 folate was the most dominant folate vitamer in soybean. • Folates are affected by accession type, ecoregion, and seed morphological traits. • Soybean is a key candidate for folate biofortification. Soybean is a rich source of folates. We optimised the extraction and detection of folates from soybean seeds by HPLC-MS/MS and analysed the folate content and composition of 1074 accessions. Total folate content ranged from 64.51 to 691.24 μg/100 g fresh weight, with 10-fold variation, and 60 elite accessions with over 400 μg/100 g of total folate were identified. The most abundant component was 5-CHO-H 4 folate, which accounted for an average of 60% of total folate content. Seed-coat colour, seed weight, ecoregion, and accession type significantly affected soybean folate content. Furthermore, 5-CH 3 -H 4 folate correlated positively with seed protein (r = 0.24***) and negatively with oil (r = -0.26***). The geographical distribution of folate according to accession origin revealed that accessions from Northeast China contain higher amounts of total folate and 5-CHO-H 4 folate. This study provides comprehensive and novel insights into the folate profile of soybean, which will benefit soybean breeding for folate enhancement. [ABSTRACT FROM AUTHOR]

Understanding the spatial variation of agricultural livelihood vulnerability to climate change is crucial for developing adaptation strategies in the future, something that has only been seldom done so far in developing economies like Bangladesh. To this end, we developed an integrated vulnerability index (IVI) based on the IPCC framework for analyzing and mapping the vulnerability of agricultural livelihoods in coastal Bangladesh. The IVI was calculated as a function of three components: exposure, sensitivity, and adaptive capacity. We used 45 indicators from nationally comparable and reliable datasets to conduct the research. Besides, a socio-economic livelihood vulnerability index (SELVI) was developed on the basis of sensitivity and adaptive capacity indicators and displayed in a scatter diagram in order to identify the socio-economically more vulnerable districts of coastal Bangladesh. A circumplex chart was used to disaggregate the normalized indices of sensitivity and adaptive capacity components, allowing the researcher to discover the factors that cause and mitigate the vulnerability. Using the IVI information, a vulnerability map was created that revealed that Patuakhali, Noakhali, Bhola, and Barguna districts in the exposed central coastal region were the topmost vulnerable districts, reflecting the fact that the agricultural livelihoods of 7.3 million people were highly vulnerable to the effects of climate change. The geographical diversity in salt intrusion, river-bank erosion, dependence ratio, crop yield, literacy, the density of physicians in the hospital, disaster-resistant houses, shelter facilities, and irrigated farming areas contributed to the diverse coastal agricultural livelihood vulnerability. • Vulnerability of agricultural livelihood was assessed by using 45 biophysical, agro-ecological, and socio-economic variables. • The drivers of livelihood vulnerability were identified by the SELVI framework to suggest location-specific interventions. • Agricultural livelihoods of exposed coastal districts are more vulnerable than the interior coastal districts. • The exposure component had a greater influence on determining vulnerability status than sensitivity and adaptive capacity. [ABSTRACT FROM AUTHOR]

Abstract: Without using an external precursor a simple and one-step method for the synthesis of C-doped TiO2 submicrospheres has been developed via hydrolysis of titanium tetraisopropoxide in pure methanol followed by calcination under air at 500°C. Also, with the addition of d-glucose and NH4OH solution during the hydrolysis process, C- or N-doped and C, N co-doped TiO2 submicrospheres can be prepared by the same method. The size of the submicrosphere was homogeneous ranging from 300 to 400nm. The resulting submicrospheres were characterized by FE-SEM, TEM, XRD, XPS and UV–vis diffuse reflectance spectroscopy. The C- or N-doped and C, N co-doped submicrospheres showed obvious absorption in the wavelength up to around 650, 500 and 650nm, respectively. The activity of the photocatalysts was evaluated by the hydroxyl radical formation under visible light irradiation. Finally, the mechanism of sphere formation is discussed. [Copyright &y& Elsevier]

Abstract: The Ag metal core–TiO2 shell (Ag@TiO2) composite nanocluster with uniform size, shape and core–shell structures was successfully synthesized by a new simple citrate reduction method. The core–shell structure of Ag@TiO2 nanocluster was characterized by using TEM, SEM, XPS, EDX, XRD, and photoluminescence spectra analysis. It was found that the Ag core is in metallic form which is covered by TiO2 shell within 3–5nm thickness and the core–shell particles size was about 30nm. The photocatalytic and photothermal cell killing efficiency of colloidal Ag@TiO2 core–shell nanocluster was evaluated against cancer (HeLa) cells under UV–vis irradiation. It was found that the Ag@TiO2 nanocluster with an adequate Ag ratio to TiO2 killed more malignant (HeLa) cells by 80% compared to TiO2 nanoparticles alone. The comparative study of the cell viability using UV only, visible only and UV–visible light revealed that the synergy effect of photocatalytic hydroxyl radical formation and Ag-plasmonic photothermal generation plays a vital role for the cancer cell killing. Based on the obtained results, a plausible mechanism was also proposed. [Copyright &y& Elsevier]