Real-Time Fluorescence Measurement for Droplet Generation and Signal Detection in a Cylindrical Tube.

This study provides an approach for generating droplets in a cylindrical tube. This creative design utilizes a single tube to generate droplets for the emulsion polymerase chain reaction (PCR). We fabricated the multi-layered tube and detected samples in 1 mm microchannel length for the minimum disposable material used for droplet signal analysis. In this research, we verify the validity of the non-planar droplet chip with a single driving pump by experimentally analyzing the light intensity of the liquids during droplet processing in real time. Experimental observation shows that droplet diameter from 150 to 285 µm was obtained by the cylindrical tube with different dispersed liquid and gas pressure settings. Average size of droplets decreased by approximately 37% as the dispersed phase liquids change at the same flow pressure of 50 mbar. In this study, the effects of the laser site, 6-carboxyfluorescein (6-FAM) dye buffer, DNA reagent, and driving pressure are analyzed directly by the signal recorded during droplet generation in the cylindrical tube. Finally, we have developed a real-time detection method to count exon 19 deletion mutations of epidermal growth factor receptor (EGFR) in a droplet using a cylindrical tube. Two digital droplet PCR methods were compared in measuring the copy numbers of EGFR with the same target DNA concentration of 105 copies/µL.

First report of target spot disease of strawberry caused by Corynespora cassiicola in Taiwan.

Strawberry (Fragaria x ananassa Duch.) is an important crop worldwide. Tontonaka, Aroma and Benihoppe, are most popular cultivars in Taiwan, especially cv. Aroma is dominated in the market. In September 2021, the target spot outbreak occurred on the leaves of cv. Aroma and Benihoppe in Nantou County. In a greenhouse, the target spot incidents were estimated at 90-100% and 40-50% in Aroma and Benihoppe, respectively, and caused 2~5% plants lost. Between April and June of 2022, the target spot occurred in another greenhouse where the target spot incidents were 90% and 5-8% in Aroma and Benihoppe, respectively. Early symptoms were small and circular to irregular brown spot on the leaves with its diameter at 1-2 mm. Then the brown lesion expanded to 2-5 mm in diameter with pale green halo. Some lesions appeared with gray center, and 2-3 spots might merge into one lesion, and some lesions were surrounded with yellow tissues later. The round to oval brown spots were also observed on stems. Ten symptomatic leaves and stems each were collected for pathogen isolation. Pieces of tissue from the edge of the brown lesion on leaf were cut and disinfested with 0.6% NaOCl for 30 sec, and rinsed three times with sterile distilled water (SDW) followed by being placed on 2% water agar. The isolates obtained from symptomatic leaves/stems of Aroma and Benihoppe showed same colonies with 100% isolation rate. Isolates from cv. Benihoppe (Cos21-1) and Aroma (Cos21-2) were selected for further observation and tests. Colonies on potato dextrose agar exhibited gray aerial mycelium at 28 °C in dark after 7-day. Conidiophores were brown, single or in clustered, unbranched, 2 to 11 septa. Conidia were 5.6-6.7× 28.1-270.0 µm (n=50) in size with obclavate to cylindrical shape, 1 to 16 septa, and olivaceous to dark brown. Based on the morphology, two fungal isolates were identified as Corynespora cassiicola. Four regions, internal transcribed spacer (ITS), ß-tubulin, translation elongation factor (TEF), and actin, were used to confirm the two isolates. Sequences of ITS and ß-tululin shared 100% identity to ITS (MZ093622) and ß-tululin (MW961419) of C. cassiicola in GenBank. Sequences of TEF and actin shared 99.60% and 99.70% identity to C. cassiicola (MK882240 and FJ853005), respectively. For the pathogenicity test, the conidial suspension (1x105 spores/ ml) of Cos21-1 and Cos21-2 was sprayed on leaves of two-month-old strawberry cv. Benihoppe and Aroma without wounds, respectively. Three plants each with more than two leaves were spray-inoculated with the selected isolates whereas three plants with SDW as controls and the test was repeated once. Inoculated plants were covered with plastic bags in the greenhouse, then removed when the initial symptoms were observed on leaves 5 days after inoculation whereas symptoms on stems were observed within 7 days. Re-isolation of the pathogens from the symptomatic leaves/stems demonstrated that the pathogen was C. cassiicola. The leaf spot or target spot caused by C. cassiicola on strawberry has been reported in Mainland China and North America. To our knowledge, this is the first report of target spot disease of strawberry caused by C. cassiicola in Taiwan.

Effects of Workplace Gossip on Employee Mental Health: A Moderated Mediation Model of Psychological Capital and Developmental Job Experience.

Research has demonstrated the effects of workplace gossip on employees' work attitudes and behaviors. However, little emphasis has been placed on the psychological influence of workplace gossip on employees. The present study investigated the relationships among workplace gossip, psychological capital, and individual mental health. Data were collected in three waves from 222 full-time employees of a Taiwanese tourism company to explore the effect of workplace gossip on employees' mental health. The results suggested that workplace gossip was associated with employees' mental health through psychological capital. Moreover, developmental job experience plays a moderator role in the relationships among workplace gossip, psychological capital, and mental health. A moderated mediation model was also proposed in this study.

Surveillance of Rice Blast Resistance Effectiveness and Emerging Virulent Isolates in Taiwan.

Rice blast caused by Magnaporthe oryzae is a dangerous threat to rice production and food security worldwide. Breeding and proper deployment of resistant varieties are effective and environmentally friendly strategies to manage this notorious disease. However, a highly dynamic and quickly evolved rice blast pathogen population in the field has made disease control with resistance germplasms more challenging. Therefore, continued monitoring of pathogen dynamics and application of effective resistance varieties are critical tasks to prolong or sustain field resistance. Here, we report a team project that involved evaluation of rice blast resistance genes and surveillance of M. oryzae field populations in Taiwan. A set of International Rice Research Institute-bred blast-resistant lines (IRBLs) carrying single blast resistance genes was utilized to monitor the field effectiveness of rice blast resistance. Resistance genes such as Ptr (formerly Pita2) and Pi9 exhibited the best and most durable resistance against the rice blast fungus population in Taiwan. Interestingly, line IRBLb-B harboring the Pib gene with good field protection has recently shown susceptible lesions in some locations. To dissect the genotypic features of virulent isolates against the Pib resistance gene, M. oryzae isolates were collected and analyzed. Screening of the AvrPib locus revealed that the majority of field isolates still maintained the wild-type AvrPib status but eight virulent genotypes were found. Pot3 insertion appeared to be a major way to disrupt the AvrPib avirulence function. Interestingly, a novel AvrPib double-allele genotype among virulent isolates was first identified. Pot2 repetitive element-based polymerase chain reaction (rep-PCR) fingerprinting analysis indicated that mutation events may occur independently among different lineages in different geographic locations of Taiwan. This study provides our surveillance experience of rice blast disease and serves as the foundation to sustain rice production.

The Safety of Drivers: Workload, Group Interaction Quality, and Psychological Strain.

OBJECTIVES: The aim of this study was to understand the relationship between employees' perception of work load, group interactional quality, and their effects on employee's psychological strain (need for recovery after work and fatigue) and job accidents. METHODS: Questionnaire was used to collect data form 401 employees in the transport service industry in Taiwan. RESULTS: (1) Workload was positively related with need for recovery after work; (2) group interaction quality was negatively related with need for recovery after work; (3) need for recovery after work was positively related with fatigue; (4) fatigue was positively related with job accidents. CONCLUSIONS: The findings highlight the importance for organizations to provide adequate work design and build a supportive working environment, which may ultimately contribute to decreased psychological strain and fewer job accidents.

Invasion and Colonization Pattern of Fusarium fujikuroi in Rice.

Bakanae disease in rice can cause abnormal elongation of the stem and leaves, development of adventitious roots, a larger leaf angle, and even death. Little is known about the infection, colonization, and distribution of Fusarium fujikuroi in rice plants across different growth stages. In this study, microscopic observation and quantitative real-time PCR were combined to investigate the pathogenesis of bakanae, using artificially inoculated seedlings of a susceptible rice cultivar, Zerawchanica karatals (ZK), a resistant cultivar, Tainung 67 (TNG67), naturally infected adult field plants (cultivars Kaohsiung 139, Taikeng 2, and Tainan 11), and an F. fujikuroi isolate expressing green fluorescent protein. In rice seedlings, F. fujikuroi hyphae were found to directly penetrate the epidermis of basal stems and roots, then extend inter- and intracellularly to invade the vascular bundles. Occlusion of vascular bundles and radial hyphal expansion from vascular bundles to surrounding parenchyma were observed in adult plants. Analysis of consecutive 3-cm segments of the whole plant revealed that F. fujikuroi was largely confined to the embryo, basal stem, and basal roots in seedlings, and distributed unevenly in the lower aerial parts (including nodes and internodes) of adult plants. The elongation and development of adventitious roots did not necessarily correlate with the amount of F. fujikuroi in diseased plants. Treatment of rice seeds with gibberellic acid-3 (GA3) at 0.5 mg/liter resulted in significantly more elongation of ZK than TNG67 seedlings, suggesting that the susceptibility of ZK to bakanae is associated with its higher sensitivity to GA3.

How does benevolent leadership lead to work-family enrichment? The mediating role of positive group affective tone.

Although researchers have confirmed the relationship between positive leadership styles and work-family enrichment, benevolent leadership has received little attention. Drawing from the concept of mood contagion, this study explores the underlying mechanism between benevolent leadership and work-family enrichment. Using a survey of 459 employees, across 36 supervisors and their work groups, and multilevel structural equation modelling, this study revealed that benevolent leadership is positively associated with work-family enrichment via cross-level paths. The results indicated that benevolent leadership is associated with positive group affective tone, which further predicts subordinates' work-family enrichment. Moreover, work engagement mediates the relationship between positive group affective tone and work-family enrichment. Theoretical and practical implications are discussed.

Exploring and Developing the Workplace Health Culture Scale in Taiwan.

Background: The aim of this study was to develop and validate the workplace health culture scale. Methods: This paper collected and re-organized current definitions about health culture from literature and created the domains and items to develop a new tool. Six enterprises and 2,431 participants were recruited from northern Taiwan for validity test. Results: We found the workplace health culture scale had appropriate reliability and validity, including a good model fit for the 25-item scale. Conclusions: Workplace health culture might be an important domain to the work of WHP. More validity and reliability studies about WHCS in wider industries and the correlation between WHCS and other WHP indicators are needed.

The Genetic Structure, Virulence, and Fungicide Sensitivity of Fusarium fujikuroi in Taiwan.

The rice disease bakanae, caused by Fusarium fujikuroi Nirenberg, has been present in Taiwan for over a century. To better understand the genetic diversity and structure of F. fujikuroi, a set of 16 polymorphic simple sequence repeat (SSR) markers were newly developed and used to analyze 637 F. fujikuroi isolates collected in 14 cities or counties around Taiwan from 1996 to 2013. On the basis of Bayesian clustering, the isolates were classified into four highly differentiated clusters: cluster B likely derived from the more widespread and genetically diversified clusters A or C, and cluster D was restricted to four cities or counties and may have been introduced from unknown sources genetically distinct from clusters A, B, and C. The coexistence of both mating types (MAT1-1:MAT1-2 = 1:1.88) and the highly diversified vegetative compatibility groups (VCG) (16 VCG among the 21 assessed isolates) suggest the likelihood of sexual reproduction in the field. However, the biased mating type ratios and linkage disequilibrium in the population suggest nonrandom mating between individuals. A significant pattern of isolation by distance was also detected, which implies a geographical restricted gene flow and low dissemination ability of F. fujikuroi. Evaluation of 24 representative isolates on eight rice varieties revealed differential levels of virulence, however no clear pattern of specific variety x isolate interaction was observed. Investigations of the differences in virulence and fungicide sensitivity between 8 early isolates (1998 and 2002) and 52 recent isolates (2012) indicate the evolution of increased resistance to the fungicide prochloraz in F. fujikuroi in Taiwan.