Screening and Identification of Yeasts Antagonistic to Pathogenic Fungi Show a Narrow Optimal pH Range for Antagonistic Activity

Microbes have evolved ways of interference competition to gain advantage over their ecological competitors. The use of secreted antagonistic compounds by yeast cells is one of the prominent examples. Although this killer behavior has been thoroughly studied in laboratory yeast strains, our knowledge of the antagonistic specificity of killer effects in nature remains limited. In this study, yeast strains were collected from various niches and screened for antagonistic activity against one toxin-sensitive strain of Saccharomyces cerevisiae and three pathogenic fungi. We demonstrate that some strains with antagonistic activity against these pathogenic fungi can be found in antagonist culture tests. These yeasts were identified as members of Trichosporon asahii, Candida stellimalicola, Wickerhamomyces anomalus, Ustilago esculenta, Aureobasidium pullulans, and Pichia kluyveri. The results indicated that the antagonistic activity of these killer yeasts has a narrow optimal pH range. Furthermore, we found that the antagonistic activity of some species is strain-dependent

Capulet and Slingshot share overlapping functions during Drosophila eye morphogenesis

BACKGROUND: CAP/Capulet (Capt), Slingshot (Ssh) and Cofilin/Twinstar (Tsr) are actin-binding proteins that restrict actin polymerization. Previously, it was shown that low resolution analyses of loss-of-function mutations in capt, ssh and tsr all show ectopic F-actin accumulation in various Drosophila tissues. In contrast, RNAi depletion of capt, tsr and ssh in Drosophila S2 cells all affect actin-based lamella formation differently. Whether loss of these three related genes might cause the same effect in the same tissue remains unclear. METHODS: Loss-of-function mutant clones were generated using the MARCM or EGUF system whereas overexpression clones were generated using the Flip-out system. Immunostaining were then performed in eye imaginal discs with clones. FRAP was performed in cultured eye discs. RESULTS: Here, we compared their loss-of-function phenotype at single-cell resolution, using a sheet of epithelial cells in the Drosophila eye imaginal disc as a model system. Surprisingly, we found that capt and ssh, but not tsr, mutant cells within and posterior to the morphogenetic furrow (MF) shared similar phenotypes. The capt/ssh mutant cells possessed: (1) hexagonal cell packing with discontinuous adherens junctions; and (2) largely complementary accumulation of excessive phosphorylated myosin light chain (p-MLC) and F-actin rings at the apical cortex. We further showed that the capt/ssh mutant phenotypes depended on the inactivation of protein kinase A (PKA) and activation of Rho. CONCLUSIONS: Although Capt, Ssh and Tsr were reported to negatively regulate actin polymerization, we found that Capt and Ssh, but not Tsr, share overlapping functions during eye morphogenesis

THE EFFECTS OF FUNGAL MEDIUM ON HATCHING RATE OF BITING MIDGE

The little black mosquitos, Forcipomyia taiwana, bite human and become one of the most annoying pests in Taiwan. Recently, the population of F. taiwana increases and invades urban and countryside. In order to effectively prevent the harassment of F. taiwana, develop control strategy is urgent and necessary. Our study found that the fungal medium influenced the length and width of the F. taiwana eggs. It also significantly decreased the hatching rate of F. taiwana. Besides, this artificial diet was more non-toxic and environment-friendly than general chemical pesticides. Thus, this study provided critical information to develop potentially useful bait of F. taiwana in the future

Distribution and associated factors of optic disc diameter and cup-to-disc ratio in an elderly Chinese population

AbstractBackgroundGlaucoma is the second leading cause of blindness worldwide and East Asian people account for almost half of those affected. Vertical elongation of the optic cup is a characteristic feature of glaucoma. However, there is a significant overlap in the vertical cup-to-disc ratio (VCDR) between normal eyes and eyes affected by glaucoma. The purpose of this study was to determine the distribution of VCDR and vertical disc diameter (VDD) and their predictive factors in a population of elderly Chinese residents in Taiwan.MethodsFour hundred and sixty elderly Chinese residents aged 72 years and older in the Shihpai district, Taipei, Taiwan participated in this study. Slit lamp biomicroscopic measurement of the VCDR and VDD after pupil dilation with a 78 diopter lens was performed by one glaucoma specialist. Multiple linear regression analyses were used to fit the best model for independent variables.ResultsThe VCDR was recorded for 438 right eyes and 430 left eyes. After excluding participants with glaucoma, the mean ± SD VCDR was 0.44 ± 0.17 for both eyes, and the 97.5th percentile was 0.8. A greater VCDR was associated with a longer axial length [VCDR = −0.47 + 0.04(axial length)] under multiple regression analysis. The VDD was obtained for 420 right eyes and 406 left eyes. The mean ± SD VDD for all participants was 1.77 ± 0.22 mm for the right eye and 1.79 ± 0.22 mm for the left eye. A higher body mass index (BMI) and a longer axial length were significantly associated with a larger VDD under multiple regression analysis. [VDD = −0.05 + 0.07 (axial length) + 0.06 (obesity); if BMI <24, then obesity = 0; if BMI ≥24, then obesity = 1]. A larger VDD was associated with a larger VCDR (p < 0.001) and the VCDR could be predicted by the equation VCDR = −0.07 + 0.3VDD.ConclusionA greater VCDR was related to a longer axial length. A greater VDD was related to a higher BMI and a longer axial length

Project dispute prediction by hybrid machine learning techniques

This study compares several well-known machine learning techniques for public-private partnership (PPP) project dispute problems. Single and hybrid classification techniques are applied to construct models for PPP project dispute prediction. The single classification techniques utilized are multilayer perceptron (MLP) neural networks, decision trees (DTs), support vector machines, the naïve Bayes classifier, and k-nearest neighbor. Two types of hybrid learning models are developed. One combines clustering and classification techniques and the other combines multiple classification techniques. Experimental results indicate that hybrid models outperform single models in prediction accuracy, Type I and II errors, and the receiver operating characteristic curve. Additionally, the hybrid model combining multiple classification techniques perform better than that combining clustering and classification techniques. Particularly, the MLP+MLP and DT+DT models perform best and second best, achieving prediction accuracies of 97.08% and 95.77%, respectively. This study demonstrates the efficiency and effectiveness of hybrid machine learning techniques for early prediction of dispute occurrence using conceptual project information as model input. The models provide a proactive warning and decision-support information needed to select the appropriate resolution strategy before a dispute occurs

Quality management platform inspired during COVID-19 pandemic for use by subcontractors in private housing projects

Due to the COVID-19 pandemic in Taiwan, many construction sites must limit the number of people on the jobsite or conduct work independently to avoid the spread of COVID-19. The quality of construction may be in doubt with unclear job handover, especially when workers have COVID-19 infection that should be isolated immediately. On top of that, first-level subcontractor self-inspections are crucial parts of construction process management, and neglecting inspection processes can lead to construction errors and poor quality. To improve current quality inspection methods for private projects, a literature analysis was conducted to identify construction quality management issues that are faced in private housing projects. In-depth interviews with small and medium-sized subcontractors of private housing projects were performed to understand the quality management methods that they use in practice. Next, improvement measures for quality management were formulated and a simplified checklist for private project subcontractors, based on the practical feedback obtained, was created. Finally, the AppSheet platform was used to develop an inspection application for construction, and a subcontractor was invited to confirm its feasibility. The paperless design avoids redundant human contact, and the results of this study greatly facilitate construction practice, particularly during the pandemic. The main contribution of this study is its investigation of the procedures that are used by private project subcontractors to inspect their work for quality management; its results can serve as a reference for academics in evaluating construction quality management levels and improving the management of work by subcontractors to promote safety and health

Risk Analysis of Cargos Damages for Aquatic Products of Refrigerated Containers: Shipping Operators’ Perspective in Taiwan

As the development of refrigerated container, transportation of aquatic products is growing rapidly in recent years. It is very important to avoid cargos damages for aquatic products of refrigerated containers, while the shipping operators are running this scope of business. Hence, the risk issue of adopting various improvement strategies would be important for the container shipping operators. In the light of this, the main purpose of this paper is to analyze the risks of cargos damages for aquatic products of refrigerated containers based on the container shipping operators’ perspective in Taiwan. We use four risk assessment procedures - risk identification, risk analysis and evaluation, risk strategies, and risk treatment - as the research method in this paper. The risk factors are generated from literature review and experts interviewing. Then, three dimensions with nineteen risk factors are preliminary identified. We used these risk factors to proceed with the empirical study via questionnaires. Three points of empirical results are presented. At first, the top factor of perceived risk as well as of risk severity is ‘container data setting errors.’ Secondly, the top factor of risk frequency is ‘lack of the goods’ pre-cooling themselves.’ Thirdly, three risk factors are classified into the low-risk area, whereas sixteen risk factors are placed on the medium-risk area. There is no risk factor fix on the high-risk area. Furthermore, three risk strategies - risk prevention, risk reduction, and risk transfer - are suggested to adopt by different risk factors

Nanoscale III-V Semiconductor Photodetectors for High-Speed Optical Communications

Nanophotonics involves the study of the behavior of light on nanometer scale. Modern nanoscale semiconductor photodetectors are important building blocks for high-speed optical communications. In this chapter, we review the state-of-the-art 2.5G, 10G, and 25G avalanche photodiodes (APDs) that are available in commercial applications. We discuss the key device parameters, including avalanche breakdown voltage, dark current, temperature dependence, bandwidth, and sensitivity. We also present reliability analysis on wear-out degradation and optical/electrical overload stress. We discuss the reliability challenges of nanoscale photodetectors associated with device miniaturization for the future. The reliability aspects in terms of high electric field, Joule heating, and geometry inhomogeneity are highlighted

Environmental literacy on ecotourism: a study on student knowledge, attitude, and behavioral intentions in China and Taiwan

This study aims to gain further insights to Chinese and Taiwanese university students’ environmental literacy on ecotourism. A structural equation model is developed and validated in an effort to explore the differences between Chinese and Taiwanese university students in terms of their environmental knowledge, environmental attitude, and behavioral intentions. The results showed that the ecotourism perception of Chinese and Taiwanese university students affect their behavioral intentions. Chinese university students exhibited a higher correlation between ecotourism knowledge and behavioral intentions than their Taiwanese counterparts. The findings also revealed differences between the Chinese and Taiwanese students in their perception of ecotourism, and this disparity was particularly evident with regards to how ecotourism should be governed. A moderate difference in ecotourism behavioral intentions was also identified, in which Taiwanese university students were less likely to engage in self-empowerment or private empowerment, to be more educated in the field of ecotourism than their Chinese counterparts