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Mitochondrial haplotypes reveal low diversity and restricted connectivity of the critically endangered batoid population in a Marine Protected Area
Get PDFStability and long-term persistence of a species rely heavily on its genetic diversity, which is closely allied to its capacity for adaptation. In threatened species, population connectivity can play a major role in maintaining that diversity, and genetic assessments of their populations can be crucial for the design of effective spatial conservation management. Not only is it worth evaluating the amount of diversity in a candidate population for protection, but the magnitude of outgoing gene flow can provide insight into its potential to replenish others via emigrants. The critically endangered flapper skate Dipturus intermedius receives protection in the Loch Sunart to the Sound of Jura Marine Protected Area (MPA) in Scotland. However, there is insufficient knowledge of genetic diversity and connectivity across its range. Recent tagging studies in the MPA suggest the presence of animals with high levels of site fidelity and residency, as well as transient individuals, raising concerns of limited connectivity to populations beyond the MPA. In this study, a newly developed mitochondrial haplotype marker allowed use of DNA sourced from fin clips, mucus and egg cases to investigate population structure and mitochondrial variability across several sites around the British Isles, including the MPA. Unfortunately, results characterized the MPA as having particularly low haplotype diversity and significant population differentiation from other sample sites. More than a quarter of its individuals carry a haplotype rarely observed elsewhere, leaving outgoing gene flow questionable. The MPA appears unlikely to sustain the species{\textquoteright} existing mtDNA genetic diversity or act as an effective source population
Data-Driven Event-Triggered Formation of MIMO Multiagent Systems With Constrained Information
No full textThis article investigates the information congestion problems for nonlinear discrete-time multi-input–multi-output multiagent systems (MASs) with fading channels when executing formation tasks. We first establish a virtual linear data model with a time-varying pseudo-Jacobian matrix variable for the MASs, which is independent of the dynamics model. Then, we formulate an event-triggered control scheme and a predictive compensation method to alleviate the communication burden and information congestion effects, respectively. Moreover, we propose two formation schemes for the MASs, considering limited communication resources, fading channels, and random delays to perform formation control and bipartite formation control tasks. The convergences of these two control protocols are strictly proved. Finally, simulations and hardware tests are conducted to verify the effectiveness of the proposed strategies
Protection Relay Setting based on Overcurrent Phenomena in Commercial Building
No full textNowadays, every single distribution system needs to install an appropriate relay to keep the system safe. The operational and commonly recommended relay for distribution systems is the overcurrent (OC) relay. Throughout the distribution system, the protective relay is one of the methods that can detect and protect the location according to its observation from any fault from abnormal activity. Note that time coordination between the protective equipment relay needs to be a minimum of time interruption to prevent faults occurs. The ideal setting for all coordination protection relays is necessary to protect the device against electrical failure and interference. This paper analyzes the real results data collected for the selected commercial building of an OC relay implemented in a distribution board for high voltage and low voltage downward at a commercial building. All the parameters need to be clarified first before testing has been made and measurement is carried out using the MICROTEST 860 set. Based on the analysis, it proves that according to the IEC Standard of 0.10-time multiplier Setting (TMS) is practical to be used to obtain the operation time in seconds for the current curve set. Other than that, the results show that the normal inverse curve from manual calculation results is more accurate compared to the service setting (SS) made based on the incoming setting in a real commercial building. The case study for OC relay setting is related between current injection and time-tripping, which complies with the IEC 60255-3 standard using its formula. This method was applied to determine the characteristics of the curve. Hence, this research successfully determined the proper methods for the OC relay setting for the power distribution system. Besides, the feasibility and efficiency of OC relay data transmission are tested and checked successfully to implement the measurement method in the relay coordination study
Teaching hospitality and tourism students’ strategies for recognizing and supporting mental health conditions and crises in industry: an exploratory study
Get PDFBy addressing the academic imperative for mental health education and crisis intervention, this exploratory study evaluates the desirability and availability of undergraduate education in recognizing and supporting mental health conditions and crises in hospitality and tourism industry settings. Hospitality and tourism management faculty and undergraduate students were surveyed through an online survey. The majority of faculty and students agreed mental health is important to learn in the classroom to prepare for industry, yet the majority have neither taught nor learned about mental health education and crisis intervention. The findings contribute to how educational leadership influences mental health training integration in classroom instruction. Recommendations included conducting feasibility studies with hospitality management educators on the integration of mental health in classroom learning; conducting larger, more generalizable studies on the effects of such education; and integrating effective mental health and crisis intervention training for hospitality management educators and students into curricula across the field
Engaging in student evaluations of teaching through intrinsic motivation: an exploratory study of competence, perceived choice, value/usefulness, and relatedness
Get PDFStudent evaluations of teaching (SET) elicit feedback to enhance the course, teaching, and learning. However, hospitality and tourism curriculum research lacks an understanding of the dyadic relationship between the instructor and motivation and other logistics to complete SET. This remains important to uncover student competence, perceived choice, value/usefulness, and relatedness to complete SET to increase SET feedback from instructors. Pearson product-moment correlation coefficient analysis was employed to test the hypotheses using data collected from 69 undergraduate hospitality and tourism students recruited through U.S. educational institutions in the northeast and southeast. Results reveal that intrinsic motivation relates positively to SET completion, showing a strong, positive correlation between all variables. The study provides contributions to instructors to offer extrinsic motivators to encourage students to recognize the value of the SET. The study is among the first to explore the intrinsic motivators and completion of SET with hospitality and tourism undergraduate students
Low-cost multiband four-port Phased array antenna for sub-6 GHz 5G applications with enhanced gain methodology in Radio-over-fiber systems using modulation instability
Get PDFPhased array antenna (PAA) technology is essential for applications requiring high gain and wide bandwidth, such as sensors, medical, and 5G. Achieving such a design, however, is a challenging and intricate process that calls for precise calculations and a combination of findings to alter the phase and amplitude of each unit. Furthermore, coupling effects between these PAA structure elements can only be completed with the use of full-wave electromagnetic simulation tools. Due to recent advances, radio-over-fiber (RoF) technology has been positioned as a possible alternative for high-capacity wireless communications. This paper presents a low-cost, multiband Sub-6 GHz 5G PAA with enhanced gain achieved through integration with a new specialized RoF system design to improve PAA performance by using the phenomenon of modulation instability (MI). Optimizing the antenna’s Defected Ground Structure (DGS) leads to even more improvement. To enable operation across three distinct frequency bands (Sub-6 GHz n78 band (3-3.8 GHz), n79 band (3.8-5 GHz), and n46 band (5-5.5 GHz)), the proposed antenna design features four elliptical patches strategically positioned at the four sides of the ground plane, providing comprehensive 360° coverage in the azimuth plane. Additionally, integrating elliptical slots and upper gaps contributes to improvement. The proposed PAA’s experimentally validated gain values are 5.2 dB, 7.4 dB, and 7.8 dB in the n78, n79, and n46 bands, respectively. For improving the performance of the proposed PAA in RoF systems, anomalous fibers ( n 2 ≠ 0 and β 2 < 0) are employed to consider the modulation instability (MI) phenomenon, which can lead to the generation of the MI gain on the carrier sideband. The true time delay (TTD) technique controls the beam pattern by adjusting the time delay between adjacent radiation elements. Furthermore, the TTD technique utilizes frequency combs for the proposed 4-element array antenna to apply MI gain to all antenna elements
Design of a new class of broad-spectrum therapeutics targeted to drug-resistant bacteria
Get PDFWe hypothesise that antimicrobial resistance (AMR) cannot be overcome by simply ‘drugging’ single biological targets, therefore, our focus is developing broad-spectrum therapeutics. Herein we present the synthesis of two novel spacer-linked, anthraquinone-triphenylphosphonium (AQ-TPP) conjugates (4) and (5) as early lead compounds in a new class of agent designed to penetrate the lipophilic barriers of the membranes of a diverse family of species; and establish bacterial growth inhibitory properties against methicillin-resistant Staphylococcus aureus (NCTC 13616) and Mycobacterium smegmatis [mc2155] (as a surrogate for Mycobacterium tuberculosis). The MIC and MBC values of (4) and (5) were determined against MRSA and found to be equipotent [MIC for each: 1 µg/mL (1.2 µM)]. Whereas the amide-linked conjugate (5) was determined to have 2-fold greater bactericidal potency [MBC 1 µg/mL (1.2 µM] than ester-linked (4). The anthraquinone-TPP conjugates (4) and (5) were active in vitro against Mycobacterium smegmatis (graphical abstract) and were equipotent as determined by their MIC values; in contrast to MRSA, the less hydrophobic (4) had 2-fold greater bactericidal potency than (5) as measured by their MBC values. Notably, both conjugates showed potent intracellular growth inhibitory activity in infected THP-1 macrophages. The conjugates are promising leads for the development of new antibacterial drugs
A Generative Design Approach for the Dynamic Optimisation of Multi-MW Offshore Direct-Drive Wind Turbine Electrical Generator Supporting Structures Using Modal Analysis
Get PDFGenerative design techniques together with the rapid development of additive manufacturing represent a revolution in the field of structural optimisation processes. In this study, a static structural and modal analysis was integrated to drive a multi-objective generative design optimisation process for a 3 MW direct-drive offshore wind turbine electrical generator rotor structure. This novel optimisation approach implements an automated fittest-for-purpose process including a static structural analysis and a modal analysis as the input for the optimisation strategy algorithm, allowing the exploration of a wide range of non-conventional topologies. If compared with the simple generator rotor disc structure, the results obtained using this innovative method achieved over 7% of weight reduction and a 39% increment in the generator operational range with the consequent growth in the wind turbine energy capture capability. Moreover, this approach generates a vast amount of structural analysis information, crucial at an early stage of the development of large-scale projects for a cost-effective scheme
Impact Analysis of Security Attacks on Mobile Ad Hoc Networks (MANETs)
Get PDFMobile ad hoc networks (MANETs) offer a decentralized communication solution ideal for infrastructure-less environments like disaster relief zones. However, their inherent lack of central control and dynamic topology make them vulnerable to attacks. This paper examines the impact of various attacks on mobile nodes within two network types: randomly and uniformly distributed stationary networks. Four types of attacks are investigated: delay, dropping, sinkhole (alone), and a combined black hole attack (dropping + sinkhole). The effects of these attacks are compared using the packet delivery ratio, throughput, and end-to-end delay. The evaluation results show that all single attacks negatively impacted network performance, with the random network experiencing the most significant degradation. Interestingly, the combined black hole attack, while more disruptive than any single attack, affected the uniformly distributed network more severely than the random network
Coming and going: A narrative review exploring the push-pull factors during nurses’ careers
Get PDFBackground: Shortages of nurses are one of the biggest challenges healthcare systems face around the world. Given the wide range of contexts and individuals working in nursing, a ‘one-size-fits-all’ retention strategy is unlikely to be effective. Knowing what matters most to nurses at different career stages would help employers and policy-makers who want to enhance nurse retention to design tailored strategies. Objective: To review and synthesise findings from recently published literature on the push-pull factors influencing nurses’ decisions at the micro level, to enter and stay (or leave) at key career stages (i.e. pre-career, training, early-, mid- and late-career, and return to practice).Methods: We undertook a set of structured searches of the literature and a narrative synthesis to explore factors that motivate individuals to enter the nursing profession and the push-pull factors influencing nurse retention at different career stages. Electronic databases CINAHL, Medline, Scopus and Embase were searched in December 2022 (and updated in November 2023) for English language publications. Additional health workforce sources, such as King’s Fund and Nuffield Trust, were also searched. Results: 227 articles met the criteria for inclusion in the narrative review. Some push-pull factors were common to nurses across all career stages, including workplace support, flexible schedule patterns, opportunities for career advancement, fair treatment and salaries. In contrast, some challenges and push-pull factors were unique to each career stage. Students experienced difficulty in adjusting and balancing education and life; early-career nurses experienced transition shocks; mid-career nurses were frustrated by the lack of career advancement; late-career nurses desired more recognition; nurses returning to practice were discouraged by their lack of confidence and the cost of return-to-practice courses. Conclusion: Our findings reinforce the view that factors influencing nurses' choices about whether to enter, continue or leave nursing jobs are multi-factorial and multi-dimensional. Policy and employment practices should be informed by research that has a more nuanced insight into what matters most to whom and at what career stage
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