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This purpose of this study is to investigate the structural and morphology of hybrid silver-crosslinked chitosan thin films potentially for surface plasmon resonance (SPR) sensor application. Silver, silver-chitosan and silver-crosslinked chitosan (annealed) thin films also were prepared as controls for this study.

Silver was firstly coated on top of the glass substrate by magnetron sputtering method. Different chitosan solutions (with and without glutaraldehyde) were coated on top of the substrate by spin coating method. Annealing treatment was carried out for one of silver-crosslink chitosan sample. The structural and morphology of all the thin films were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The SPR curves also were measured by the SPR sensor with air and deionised (DI) water as analytes.

The structure of silver-crosslinked chitosan thin film presented a monoclinic structure with high crystallinity of 131.71 nm at the prominent peak by XRD analysis. The FESEM and AFM analyses revealed the morphology to be rough in surface attributed to enhanced contact with analytes in SPR measurement compared to other thin films.

In the present study, the glutaraldehyde used to crosslink the thin film increased hydrophobicity and allows for more binding capacity.

The proposed silver-crosslinked chitosan thin film may prove beneficial for biosensing such as in environmental applications by SPR sensor.

This paper aims to study the working principle of the capacitive pressure sensor and explore the distribution of pressure acting on the surface of the capacitor. Herein, a kind of high sensitivity capacitive pressure sensor was prepared by overlaying carbon fibers (CFs) on the surfaces of the thermoplastic elastomer (TPE), the TPE with high elasticity is a dielectric elastomer for the sensor and the CFs with excellent electrical conductivity were designed as the conductor.

Due to the excellent mechanical properties and electrical conductivity of CFs, it was designed as the conductor layer for the TPE/CFs capacitive pressure sensor via laminating CFs on the surfaces of the columnar TPE. Then, a ‘#' type structure of the capacitive pressure sensor was designed and fabricated.

The ‘#' type of capacitive pressure sensor of TPE/CFs composite was obtained in high sensitivity with a gauge factor of 2.77. Furthermore, the change of gauge factor values of the sensor under 10 per cent of applied strains was repeated for 1,000 cycles, indicating its outstanding sensing stability. Moreover, the ‘#' type capacitive pressure sensor of TPE/CFs was consisted of several capacitor arrays via laminating CFs, which could detect the distribution of pressure.

The TPE/CFs capacitive pressure sensor was easily fabricated with high sensitivity and quick responsiveness, which is desirably applied in wearable electronics, robots, medical devices, etc.

The outcome of this study will help to fabricate capacitive pressure sensors with high sensitivity and outstanding sensing stability.

This paper aims to propose a new microfluidic portable experimental platform for quick detection of heavy metal ions (HMIs) in picomolar range. The experimental setup uses a microfabricated piezoresistive sensor (MPS) array of eight cantilevers with ion-selective self-assembled monolayer's (SAM).

Most of the components used in this experimental setup are battery operated and, hence, portable to perform the on-field experiments. HMIs (antigen) and thiol-based SAM (antibody) interaction start bending the microcantilever. This results in a change of resistance, which is directly proportional to the surface stress produced due to the mass of targeted HMIs. The authors have used Cysteamine and 4-Mercaptobenzoic acid as a thiol for creating SAM to test the sensitivity and identify the suitable thiol. Some of the cantilevers are blocked using acetyl chloride to use as a reference for error detection.

The portable experimental platform achieves very small detection time of 10-25 min with a lower limit of detection (LOD) 0.762 ng (6.05 pM) for SAM of Cysteamine and 4-Mercaptobenzoic acid to detect Mn2+ ions. This technique has excellent potential and capability to selectively detect Hg2+ ions as low as 2.43 pM/mL using SAM of Homocysteine (Hcys)-Pyridinedicarboxylic acid (PDCA).

As microcantilever is very thin and fragile, it is challenging to apply a surface coating to have selective detection using Nanadispenser. Some of the cantilevers get broken during this process.

The excessive use and commercialization of NPs are quickly expanding their toxic impact on health and the environment. Also, LOD is limited to nanomolar range. The proposed method used the combination of thin-film, NPs, and MEMS-based technology to overcome the limitation of NPs-based technique and have picomolar range of HMIs detection.

This study aims to investigate whether underwriters exercise their allocation discretion to offer favorable discounts to institutional investors.

The research covers 173 offerings at Borsa Istanbul between 2010 and September 2021. Two hypotheses related to allocation discretion are developed and tested by means of probit, ordinary least squares and two-stage least squares regressions. Heckman selection regressions are used for robustness tests.

Allocation discretion is catered toward institutional investors who account for more than 56% of all initial allocations adjusted by gross proceeds. Close to 84% of all gross proceeds come from offerings that allocation discretion is exercised. These discretionary offerings are sold with larger price discounts, yet provide lower initial returns, while evidence points to reallocation to retail investors due to weak demand from institutional investors.

Despite using the population of firms in the research period, the sample size is small relative to more developed markets. The research period cannot be extended because allocation discretion is allowed in 2010.

The research highlights the importance of institutional and foreign investors to the equity markets. This issue is relevant due to the ongoing flight of foreign investors from emerging economies and the increasing participation of small investors in the stock markets.

The study cautions retail investors against greater (re)allocations by underwriters who may seek to compensate for the loss of their foreign investor base and urges policymakers to regain foreign investors.

To the best of the authors’ knowledge, this is the first research paper to use actual discounts disclosed in the prospectus to test the predictions related to allocation discretion. The study also contributes to the emerging markets literature by documenting allocation practices of the Turkish underwriters for the first time.

The last two years are characterized by record numbers of initial public offerings (IPOs), foreign investor abstinence and rising retail investor appetite in the Turkish stock market. This study aims to investigate whether retail investor dominance coupled with foreign investor aversion has significant impact on initial and short-term returns.

The research covers the population of 188 companies going public at Borsa Istanbul from 2010 to the end of 2021. Three hypotheses are developed and tested by means of ordinary least squares and Tobit regressions to examine the association between investor allocations and returns. A new measure for retail investor trade size, average retail investment per capita (ARI) is utilized to explain the linkage between retail investor appetite and short-term returns. Two-stage least squares and Heckman selection regressions are employed for robustness tests to address potential endogeneity.

Pandemic IPOs provide significantly larger short-term returns than pre-pandemic IPOs measured up to one month. Underpricing during the pandemic is not significantly greater due to 10% daily price limit, which leads to a gradual release of retail investor appetite and increase in stock prices in the short term. Retail investors control 66% of the market during the pandemic compared to 35% before, while foreign institutional investor market share declines from 53% to 6%. Average retail investor number in an offering increases by 55.4-fold during the pandemic, resulting in substantially smaller allocations to the average individual investor. Greater returns during the pandemic are associated with smaller retail investment per capita, while domestic institutional investment is associated with lower returns as typically expected from institutional investors, although its significance disappears after controlling for potential endogeneity.

This study investigates returns up to one month. To better understand whether short-termism of retail investors and recent foreign investor aversion have detrimental effect on companies, and on the market as a whole, longer-term studies are needed. This is not possible at the current stage since not enough time has passed.

This research is relevant to emerging market investors and companies due to the ongoing foreign investor aversion and fast-changing market conditions. The research cautions market participants against the short-termism of retail investors and urges policymakers to regain investors with longer investment horizons.

Many newcomer retail investors are in the stock market due to lack of more profitable alternatives in Turkey. Although their participation is accompanied by larger short-term returns for the time being, the current momentum is unlikely to last long as the pandemic ends, and interest rates around the world begin to be raised. The study urges small investors to invest in a more informed manner and aim for longer time horizons, as it may not be possible to make a quick profit in the stock markets in the near future.

This is the first study to investigate changing investor profile in emerging markets and its impact on returns following pandemic declaration. The question is important because the investor composition affects the investment horizon in the market.

This study aims to investigate whether organisational climate (OC) predicts academic staff performance at Malaysian higher education institutions (HEIs). The study equally aims at validating the psychometric properties of OC and workforce performance (WFP) constructs.

Survey questionnaires were administered to 800 academic staff of eight selected HEIs. Principal component analysis, confirmatory factor analysis, full-fledged structural equation modelling and multiple regression analysis were performed to explore the underlying factors and test the factorial validity of the constructs.

The analysis yielded a five-factor index for the OC construct, whereas the WFP construct comprised two factors. The findings reveal a strong predictive causal effect between OC and WFP. These results suggest that establishing a positive OC enhances academic staff performance. Furthermore, the hypothesised model adds new knowledge to the literature of OC, from the Malaysian context, which could be used to predict WFP at the tertiary level.

The study concludes by discussing the theoretical and practical implications of the findings for HEIs.

This paper makes a significant contribution to the understanding of how OC could be used as an effective instrument in improving academic staff performance in the context of Malaysian HEIs.

The purpose of this paper is to examine the relationship between headteachers and teachers and its effects on the role of trust in Malaysian high-performing schools through the dyadic relationship theoretical approach.

Using a survey questionnaire, a total of 199 teachers from five high-performing schools were selected as respondents for data collection. Before proceeding with inferential statistical analysis, teachers were separated into the “in-group” and “out-group”.

The findings revealed that the teachers from both the groups perceived that their facets of trust are strongly associated with the type of relationship they have with their school leaders. The results also demonstrate that the quality of dyadic relationships between headteachers and teachers moderately influences teachers’ trust.

The findings suggest that the headteachers should always build good relationships with the teachers to gain teachers’ trust for sustaining school effectiveness. The findings encourage the Ministry of Education, particularly the Teacher Recruitment Division, to require all teachers and headteachers to deepen their knowledge on leader-member exchange (LMX) role-development processes.

The results are of great importance since limited empirical studies have examined LMX role-development processes with reference to teachers and headteachers in the context of Malaysian higher performing schools.

This paper aims to examine the role of senior managers’ use of financial and non-financial performance measures in the relationship between decentralization and organizational performance in the hotel industry.

Data were collected using a mailed questionnaire. General Managers in charge of medium-to-large hotels in Thailand completed the questionnaire. In total, 131 general managers, one from each hotel, participated in the study. Path analysis technique was used to test the hypotheses.

The results indicate that the general managers’ use of financial and non-financial performance measures fully mediates the relationship between the extent of decentralization of decision-making and hotel performance. The results reveal that the decentralization of decision-making alone is not enough to help a hotel improve its performance. Indeed, the relationship between decentralization of decision-making and hotel performance exists only via the general manager’s use of the performance measures. It is contended that a general manager’s use of the performance measures in a hotel encourages department managers to make appropriate decisions to successfully improve their department’s performance which, in turn, leads to increased performance of the hotel.

This study provides empirical evidence indicating how senior managers in hotels with decentralized decision-making could use performance measures to better manage their hotels, thereby improving the hotel’s performance. An in-depth analysis of the data reveals that the senior manager’s use of the non-financial, and not the financial, performance measures is a mediator of the relationship between decentralization of decision-making and hotel performance.

Effective refractive error (RE) coverage in a resource-constrained country such as Kenya could possibly be achievable if the current dominant commercial entrepreneurship is supplemented with alternative avenues such as social entrepreneurship. This study aims to explore the perceived impact of social enterprises (SEs) in scaling effective RE coverage in Kenya.

This was an exploratory study with data collected from representatives of SEs (n = 29), trainees of SEs (n = 112) and beneficiaries of eye care services provided by SEs (n = 674). Participants were recruited purposively with data collected through telephonic calls. Thematic analysis was carried out by categorizing the codes into categories and themes based on the semantic meaning of the codes.

The perceived impact of SEs from the representative perspective included entrepreneurship and livelihood (n = 3; 10.3%), skills development (n = 20; 69%), technology development (n = 7; 24.1%), access to specialized services (n = 7; 24.1%) and affordability, accessibility and availability of RE services (n = 27; 93.1%). From the perspective of trainees, the themes included economic empowerment (n = 99; 88.4%), improved quality of life (n = 84; 75.0%), sensitizing locals to RE during screening events (n = 112; 100.0%) and enhancing accessibility, availability and affordability (n = 107; 95.5%).

The perceived impact of SEs highlighted in this paper showcases that they are useful for integration into the eye health ecosystem in a resource-constrained country such as Kenya. Integration of SEs into the eye health ecosystem could potentially address the human resource challenge, scale RE service delivery, enhance awareness creation and address the cost barriers to current RE service delivery coverage.

The article aimed to use sourdough powder as a natural preservative against mould growth and a glycemic index reducer agent.

In this study, muffin production was carried out with sourdough powder addition at the rate of 0, 15 and 30%. To obtain the sourdough powder, sourdough was fermented by using Lactobacillus fermentum, Lactococcus lactis (previously isolated from spontaneous sourdough) and Saccharomyces cerevisiae.

The specific volume, number of crumb pores and total pore area were not adversely affected by the addition of 15% or 30% sourdough powder (p > 0.05). The sourdough addition reduced the L* values of the muffin crust, while the b* value of the muffin crumb with 30% sourdough powder decreased compared to the control (p < 0.05). The addition of sourdough powder decreased eGI and RDS values and increased SDS content of samples (p < 0.05). In storage, the mould growth was observed in the control group and samples containing 15% sourdough powder on the 5th day, while the samples containing 30% sourdough powder were moulded on the 7th day. The sourdough powder increased the hardness and chewiness values of samples (p < 0.05), while it had no significant effect on springiness, cohesiveness and resilience (p > 0.05).

The sourdough powder provides a lower glycemic index and longer microbial shelf life that makes the product advantageous in consumer demand. This is the first time sourdough powder has been used to achieve this purpose.