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The weekend effects on healthcare professionals\ue2 need for recovery from work: the serial mediation effect of recovery and affective experience
No full textResearch background: With the emphasizing of protection of labor rights in social change, concerning about work hour has been the main issue of labor relations and human resource management. Generally, the non-work time on weekends provides a context for workers to restore their energy and resource for work. However, the job characteristics of caring patients make medical practitioners hard to separate work time and non-work time. Therefore, it is important to explore the recovery effects form differential recovery experiences on medical practitioners.
Research objective: To explore the relationships between weekend recovery experience, weekend affective experience and need for recovery among medical professional employees.
Materials and methods: The study was conducted with a longitudinal field study design. Data was collected with a self-administrated questionnaire from the medical care employees in two medical institutions in Southern Taiwan. 322 participants finished the investigation. We empirically analyzed the serial mediated effect of weekend recovery experience on weekend affective experience and need for recovery.
Results: Weekend did make a statistically significant enhancement on healthcare professionals\ue2 need for recovery from an average of 58.75 before weekend to an average of 54.66 in the end of weekend. No differences were found for the weekend effectiveness among job types of healthcare professionals with repeated measured analysis, including physicians, nurses, nutritionists, pharmacy. Additionally, three kinds of directed effects were shown for the relationships between recovery experience and weekend affective experience, including the reverse effect for psychological detachment, expected effect for relaxation experience and experiencing control, and no-effect for mastery experience. Finally, the serial mediating effects were found that healthcare professionals make weekend recovery effectiveness from the improvement of weekend negative affective experience through several recovery experiences.
Conclusions and Suggestions: This study proposed and verified the effectiveness of recovery experience related to the measurement of weekend recovery process and their theoretical relationship with the recovery of affective experience and need for recovery. Based on our empirical results, suggestions were made for systematically combining policies of employee rest and health promotion at work and human resource management mechanisms in hospitals, including recovery from work as the basis for human resource management mechanism for maintaining homeostasis of physical and psychological loadings of workers, and incorporating human resource buffer mechanisms into arrangements for human resource planning and work design
The molecular mechanism of autophagy-modulated apoptosis in leukemia cells
No full textPrevious studies have shown that autophagy plays a dual role in inhibiting or maintaining the growth of leukemia cells during the initiation or progression of leukemia. Therefore, understanding the mechanism of autophagy in drug-induced apoptosis may provide strategies for eliminating drug resistance in leukemia cells and enhancing drug cytotoxicity to these cells. In this study, we investigated the causal relationship between autophagy and apoptosis in leukemia cells treated with YM155, BH3 mimetics (WEHI-539/ABT-199), and AMPK inhibitor Compound C. Our data showed that YM155 promoted HuR mRNA degradation was mediated through p38 MAPK-triggered activation of autophagy in chronic myeloid leukemia K562 and MEG-01 cells. Downregulation of HuR destabilized Survivin and MCL1 mRNA and reduced their expression, leading to trigger apoptosis in YM155-treated K562 and MEG-01 cells. On the other hand, YM155 induced autophagic degradation of Sp1 protein in acute myeloid leukemia U937 and HL-60 cells. As Sp1 transcriptionally upregulated the expression of Survivin and MCL1, YM155 induced apoptosis in these cells. Inhibition of Survivin and MCL1 expression by YM155 attenuated the resistance of K562 cells to ABT-199 cytotoxicity and sensitized U937 cells to daunorubicin cytotoxicity. Accumulated evidence has indicated that sustained exposure to benzene metabolite hydroquinone (HQ) induces transformation of U937 cells into U937/HQ cells with malignant phenotypes. WEHI-539 accelerated \uce\ub2-TrCP mRNA turnover through NOX4/ROS/p38 MAPK axis-mediated autophagy in U937 and U937/HQ cells. Downregulation of \uce\ub2-TrCP increased Sp1-mediated NOXA transcription, which in turn promoted NOXA-mediated degradation of MCL1 protein. Combined treatment with WEHI-539 with ABT-199 showed a synergistic cytotoxicity to U937 and U937/HQ cells, while WEHI-539 sensitized ABT-199-resistant U937 cells to ABT-199 cytotoxicity. Compound C induced mTOR-independent autophagy, which in turn inhibited TET2 expression, thereby activating apoptosis in U937 and U937/HQ cells. Blocking Compound C-triggered autophagic flux attenuated its induction of apoptosis. As a result, co-treatment with rapamycin (an mTOR inhibitor) increased the cytotoxicity of compound C by activating autophagy. Taken together, the data from this study indicate that YM155, BH3 mimetics, and Compound C regulate the expression of HuR, Sp1, \uce\ub2-TrCP, or TET2, respectively, to promote apoptosis in leukemia cells. Uncovering these mechanisms allows us to further investigate the utility of these drugs in combination with chemotherapy drugs in improving the treatment of leukemia
Chest-Worn Cardiovascular Activity Monitors Based on Self-Injection-Locked Doppler Radar
No full textThis dissertation presents the use of self-injection-locked (SIL) Doppler radars with chest-worn tags for monitoring the cardiovascular activities of a mobile person. There are two types of chest-worn tags used in this research-active tag and passive tag. The radar using the active tag operates at 5.8 GHz and consists of a self-injection-locked oscillator (SILO) tag and a frequency modulation (FM) receiver. The first SILO tag antenna is designed using metasurfaces for vital-sign detection. This antenna comprises a frequency selective surface (FSS) and an electromagnetic bandgap (EBG) surface to reject the moving clutter and eliminate the body-proximity effect. The second SILO tag antenna is designed with a complementary split ring resonator (CSRR) for near-field sensing to monitor heart rate variability (HRV). To improve the antenna directivity towards the heart area, the third SILO tag antenna is designed with a partially reflective surface (PRS) that is composed of an array of split ring resonators (SRRs). Moreover, the combined ensemble empirical mode decomposition (EEMD) and principal component analysis (PCA) algorithm is proposed to remove respiratory and body motion artifacts in the extraction of the heartbeat signal, yielding accurate estimates of cardiac timings. To miniaturize the SILO tag for the convenience of measuring heart sounds at different auscultation sites, the fourth SILO tag antenna is designed using a stacked structure of a loop antenna and a concentric loop. Furthermore, a hidden semi-Markov model (HSMM) is applied to segment the heart sound signal. Finally, a transmitarray lens is designed as the passive tag to focus the incident wave from a remote 5.8 GHz SIL Doppler radar on a specific area of the heart via penetration into the chest for long-term HRV monitoring
Performance Analysis of Passive and STAR-RIS-assisted Wireless Systems with IFBL and FBL Communication
No full textThe adaptation of different architectural setups of reconfigurable intelligent surfaces (RIS),
namely: passive, active and simultaneous transmitting and reflecting (STAR), in cooperative wireless networks has led to a technological revolution aiming to provide higher
spectral and energy efficiencies with a wider coverage area. In this thesis, with the objective of providing novel analytical frameworks, we study the performance of different RIS-assisted (passive- and STAR-RIS) multi-user wireless communication scenarios
under infinite blocklength (IBL) and finite blocklength (FBL) codes with the aid of nextgeneration technological advancements such as full-duplex (FD), non-orthogonal multiple
access (NOMA) and rate splitting multiple access (RSMA), etc. In particular, we first derive the probability density function (PDF) and cumulative distribution function (CDF)
of the signal-to-interference-plus-noise ratio (SINR) for each scenario. We then analyze
the system performance by deriving closed-form expressions of key performance metrics
such as outage probability, throughput, block error rate (BLER), goodput, etc. Moreover,
we validate the accuracy of the derived analytical expressions graphically using MonteCarlo simulations. We also discuss the impact of key system parameters such as transmit
power, number of RIS elements, blocklength, operating modes in the case of STAR-RIS,
imperfect channel state information, etc., on the performance of the respective considered
communication system
Spectrum-Efficient Design in Wideband MIMO Systems Assisted with Reconfigurable Intelligent Surface
No full textMany key enabling technologies (referred to as disruptive technologies) have been proposed to be integrated into the communication system to enhance its performance indicators, such as latency, reliability, mobility, and energy efficiency. They are deployed under different communication scenarios along with their respective inherent characteristics and advantages. These disruptive technologies include intermediary devices such as relays, back scatters, and reconfigurable intelligent surfaces that assist in data transmission. The latter, known as RIS, is a surface consisting of many reflecting elements (REs) which can alter the amplitude and phase shift of an RF signal by a particular amount of value. Unlike relays, RIS does not need active circuit components, which makes it a popular solution for energy efficiency issues for wireless communication.
This study considers the spectrum efficiency design of a wireless system utilizing RIS to assist data transmission. In particular, this study works on single-point MIMO and SISO-wideband systems where a RIS is deployed to enhance the overall spectral efficiency. In both scenarios, we seek optimal RIS reflection coefficients and power allocation that lead us to a particular design of algorithms. The global optimal for power allocation is obtained by using the low-complexity water-filling algorithm. The design for the optimal RIS reflection coefficient is challenging since it is generally non-convex. For the MIMO system, we propose the Dimension-wise Sinusoidal Maximization (DSM) that efficiently solves the reflection coefficient problem. We use the gradient descent technique to get the optimal RIS phase shifts for the wide band system
Applications of partial traces in quantum information theory
No full textQuantum data are presented by density matrices. In this thesis, we study density matrices. In a bipartite or a multipartite system, we consider the problem how to split a density matrix into a tensor product of two or more density matrices by the method of using partial traces. Using our results, we investigate the problem whether a quantum state, that is, a density matrix, is a separable state or an entangled state in a bipartite system or a multipartite system. Furthermore, we define and present simple properties of completely positive maps and quantum channels. We also demonstrate the problem why positive maps, in general, cannot deal with entangled states
Microevolutionary Studies on Selaroides leptolepis (Carangidae) from the Tropical Western Pacific
No full textAbstract
The family Carangidae (Teleostei: Perciformes) is an economically important fish group for the capture fisheries industry. Most of its ~140 member species are generally
consumed as food and exhibit a wide array of morphology and aquatic lifestyle. One taxon, Selaroides leptolepis, is largely abundant in the Tropical Western Pacific (TWP) waters
and constitutes a vital part of artisanal fisheries in the region. Despite such significance, this species remained relatively understudied, especially in its evolutionary aspects, as
compared to its confamilial relatives. In this dissertation, I presented independent yet interrelated studies into the microevolutionary aspect of the species and its family. For
the opening chapter, I introduced the taxon and its relevance in the TWP region. The current knowledge boundary and existing research gaps, which this study is trying to address, were also identified in the introductory portion.
In the second chapter, I presented the first genetic assembly of the S. leptolepis in TWP using mitochondrial cox1 and cytb markers. Both markers coherently showed the close structuring of an Asian lineage (i.e., Malaysia, Taiwan, Philippines, Japan, India, and Arabian Peninsula) and its deep divergence against Australian lineage (FCT 0.8847~0.9491). Pairwise difference values (K2P>6%) across the two were intermediary between intraspecies (K2P10%) range, and comparable to that of other potentially cryptic species observed within Carangidae. Therefore, this study resolved that the two groups are also cryptic lineages within the species. Reconstruction of the demographic histories also indicated that populations have undergone a recent expansion. Calculations showed that the most drastic increase
occurred between 21 to 10 thousand years ago, concurrent with the events of the Last Glacial Maxima (LGM).
In the next chapter, I set out to morphologically discriminate the members of the two lineages through an integrated morphometrics approach. Voucher specimens collected throughout TWP were initially assigned to a priori groupings based on the genetic knowledge presented above. We performed comparisons through (1) conventional lineal morphometrics with meristics, landmark-based (2) truss, and (3) geometric morphometrics. The calculations revealed highly overlapped ordination diagrams across all techniques indicating very close morphometries of the two groups.
Discriminant and cluster analyses both showed poor discriminatory powers, suggesting the presence of a single morphological unit. This work further supported the identities as \ue2morphologically indistinguishable yet genetically distant\ue2 members of the species.
With the cumulative knowledge derived from the previous studies, the fourth chapter aimed to test the diagnostic usability of these mitogenomes in detecting population-level or cryptic speciations in Carangidae. I collated and phylogenetically compared all the available carangid mitogenomes and detected geographically related divergences in some taxa. These divergences were also highly corroborative from related studies which used different diagnostic markers. Divergence time estimates suggested that most intraspecific diversifications date back to Late Neogene, particularly with the bifurcation of S. leptolepis lineages at approximately 5.38 MYA ago. Additionally, I characterized the mitochondrial genomes sets of the two different S. leptolepis lineages. Annotations revealed that both mitogenomes contained 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer rRNAs, and a control region \ue2 which is a common feature for teleosts. Supplemental analyses also displayed consistent cross-lineage sequence variations on nuclear markers. These findings are crucial in understanding the history of cryptic lineages in the context of evolution
Design of a low-power neural network circuit based on reduced data transmission and multiple clock domains
No full textThe architecture design of the neural network accelerators has become an important topic in recent years especially on how to reduce the power consumption of the accelerators. Therefore, this thesis proposes two design techniques for an existing reference accelerator architecture, which can help reduce the power dissipation. First, the original architecture adopts a method of dynamic tile size based on output reuse. The optimal tile size can be selected according to the parameters of each layer of neural network in order to accommodate either more input or output channels at the same time in order to achieve the best data reuse. This thesis further combines the existing on-chip input and output buffers together such that some buffers can be dynamically allocated to the input or output channels without incurring too much additional circuit cost. According to our experiments, the overall external memory accesses can be further reduced by about 9%~21% for some famous neural network models such as Yolo V3 Tiny, VGG16 and AlexNet. In addition, when the reference accelerator design is implemented on the Xilinx ZCU102 FPGA platform, due to the platform\ue2s limitation, very often its data transmission rate will be lower than data processing throughput in processing some network layers. Therefore, this thesis applies clock domain crossing (CDC) technology to the accelerator such that the data transmission and data processing modules can operate at different clock frequencies. Our experimental results show that when the accelerator processes some layers with small feature maps and small kernel sizes such as 3x3 or 1x1 convolution, the power consumption can be reduced by up to 70.72%
Governance Mechanisms of Ecosystems in Digital Ticket Platforms: The Transaction Cost Perspective
No full textThis study takes Transaction Costs Theory as the core to explain that when enterprises build platforms, transaction costs will be incurred due to different delivery methods of goods. The digital platform connects internal and external resources to create the development of multilateral markets and cross-border platforms. The development of platform companies has different governance mechanisms for internal organization or outsourced operation. Enterprises usually evaluate and choose an operating mechanism with relatively low transaction costs.
Through the transaction characteristics (including transaction frequency, asset specificity, uncertainty) and other issues in the transaction cost theory, we pointed out that traditional enterprises will assume that there are no interfering variables in the transaction status , but in the process of real digital ticket platform transactions, the platform is necessary to control the risk and standardize the transaction process first, so that enterprises can choose the suitable operation model according to the needs of the enterprise in the face of platform operation. The internalization of external resources of multinational enterprises and the minimization of transaction costs of location factors proposed in IB theory are the difficulties that multinational enterprises need to face in the process of increasing their ownership advantages. Through the transfer of people, to complete the transaction through the movement of personnel, and through the physical sensing and transmission back to the digital platform system, the linkage between the digital world and the real world is realized, and a new transaction mode is created.
The development of the platform is based on the sharing system modules. In the business module of the enterprise, it is not handled by manpower, but is established and processed through a digital ticket system. Compared with the traditional service-oriented business, the delivery method will be faster and more efficient. It is easy, but due to the different delivery methods of goods or services during the operation of the platform, platform managers need to deal with issues related to platform establishment, cooperation with complementors, product delivery, transaction signals, and international cross-border delivery. The reason why the enterprise cannot run quickly, the research results found that the delivery method of the products or services of the enterprise plays a very important role in the cross-regional or cross-border business development of the platform enterprise. The complementors, suppliers and system embedders of the transactions required in the internationalization process are established first. Different from the traditional enterprise internationalization that needs to develop in the host country to enhance the ownership advantage of the enterprise's sisterhood, this research focuses on the digital platform enterprise ecosystem The various bottlenecks faced by the establishment and transaction development, after the platform operation business model management concept is formed, the application of its basic concept is converted into the style of enterprise patent protection (such as e-ticket alliance marketing),Ensure that the e-commerce and platform program design can avoid plagiarism by latecomers or provide corporate rights and interests in the future, and the final platform development is handed over to the actual operation of the platform company. However, the internationalization process of digital platforms will encounter various difficulties and bottlenecks such as logistics, cash flow, suppliers, complementors and users. It is necessary to control the possible risks, uncertainties, transaction frequency, etc. before the platform internationalization. Managed and standardized and streamlined. Finally, the platform provides two signals as the actual practice of payment and confirmation of use. The actual operation of the platform will be described after the operation of academic and practical enterprises is applied for patent protection. The research results will bring considerable contributions and enlightenment to the development of digital platforms, platform internationalization, and digital platform ecological theory and practice
Bragg reflections of oblique waves by series surface-fixed structures and submerged breakwaters
No full textWe study Bragg reflections of oblique water waves toward series surface-fixed structures over series bottoms by using the eigenfunction matching method (EMM). Based on the assumption of small amplitude wave use the linear wave theory to conduct the solving process employed in the solution procedure, and use the step approximation to slice the surface-fixed structures and the submerged breakwaters profiles into shelves and divide into several abrupt steps. The solution to each shelf is composed of eigenfunctions with unknown coefficients representing the wave amplitudes. Upon applying the conservation of mass and momentum, the linear equations of a system is obtained and solved by a sparse-matrix solver.
EMM was used to verify the Bragg reflection of waves on the fixed structure on a single submerged breakwater at different incident angles. It was found that the greater the incident angle, the higher the reflectivity was. Then the floating fixed structures and submerged breakwater were added to three or five series. It was found that the secondary frequency resonance was larger than the main frequency resonance, there is a phenomenon of shifting to the right.
Continuing with the previous model verification, in the model that EMM research only considers submerged breakwater without adding floating fixed structures, the reflectivity increases with the height of the submerged breakwaters, and decrease with the increase of the incident angle, and the main frequency resonance is larger than the secondary frequency resonance, it is also observed that the dominant frequency resonance shifts to the left with the increase of the submerged breakwaters height. When the floating fixed structure is behind the submerged breakwater, the reflection effect will be better as the distance between the structure and the submerged breakwater increases. On the contrary, when the submerged breakwater is concave, in addition to the reflectivity increasing with the wave incidence angle, when the distance between the structure and the submerged breakwater becomes longer, the reflectivity will obviously attenuate.
Then, the method is applied to solve the Bragg reflections of oblique waves in regard to the various surface-fixed structures over the series submerged breakwaters. By numerical experiments, the Bragg\ue2s law of oblique waves is used to predict the occurrences of Bragg resonance