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Objectives More self-compassion has been related to a better psychological functioning in cancer patients, but little is known about the course of self-compassion over time in the trajectory of illness and cancer treatment. This longitudinal study aimed to examine subgroups of cancer patients with differential trajectories of self-compassion and associations of these trajectories with the course of psychological symptoms. Methods A total of 153 cancer patients participated in this longitudinal study. Self-reported questionnaires were used to measure self-compassion (i.e., overall self-compassion and, separately, positive self-compassion, and negative self-compassion), and depressive and anxiety symptoms. These assessments were taken directly after cancer diagnosis (T1), and at the start (T2) and the end (T3) of medical treatment. Latent class growth modelling and repeated measures ANOVA were applied to examine the research questions. Results We identified three trajectories of overall self-compassion ("stable low" 82.2%, "late increase" 11.8%, and "late decrease" 6.0%), four trajectories of positive self-compassion ("late decline" 57.2%, "early decline" 22.4%, "large increase" 15.1%, and "large decline" 5.3%), and four trajectories of negative self-compassion ("late decline" 42.1%, "stable negative self-compassion" 40.8%, "large fluctuation" 9.9%, and "large increase" 7.2%). Only the negative self-compassion trajectories were significantly related to the course of depressive and anxiety symptoms. Conclusions Our findings suggest that subgroups of cancer patients exist that show distinct trajectories of self-compassion over time. We identified a small group of patients at a higher risk of losing self-compassion throughout the cancer trajectory and experiencing psychological symptoms.

Major depressive disorder (MDD) is associated with an increased risk of suicide and suicide attempt among cancer patients. However, we do not know how many cancer patients without MDD have suicidal ideation (SI).This study aimed to investigate the prevalence, characteristics and correlated factors of SI among advanced cancer patients without MDD.This is a multi-center, cross-sectional study based on an electronic patient-reported outcome systems in patients who were diagnosed with advanced lung, liver, gastric, esophageal, colorectal or breast cancer, the top six prevalent cancers in China. A total of 2930 advanced cancer patients were recruited from 10 regional representative cancer centers across China from August 2019 to December 2020. Patients completed the Patient Health Questionnaire-9 regarding if they had thoughts of being better off dead or of hurting themselves in some way in the previous 2 weeks. Patients also completed the symptom inventory and quality of life assessment. Generalized estimating equation model was performed to explore the correlated factors associated with SI among the patients without MDD.The overall prevalence of SI among advanced cancer patients without MDD was 13.1%. The prevalence was higher in older patients. After adjusted for existing conditions, patients with vomiting symptom (p lt; 0.001), poorer life quality (p lt; 0.001), and middle education level (p = 0.031) were correlated factors of SI.The suicidal ideation is common in advanced cancer patients without MDD. Patients with vomiting, poor quality of life, and middle education level should be screened and monitored for suicidal ideation even without MDD.ChiCTR1900024957.

This article first develops a radiated electromagnetic interference (EMI) model for a gallium nitride (GaN) integrated circuit (IC)-based active clamp flyback converter. Important capacitive couplings, which play a big role in the radiated EMI, are identified, extracted, and validated in the converter. The radiated EMI model is improved to characterize the impact of capacitive couplings. Based on the improved model, techniques to reduce capacitive couplings and the radiated EMI are proposed and experimentally validated.

Objectives An adaptive role of self-compassion for psychological functioning in cancer patients has been highlighted, yet less is known about the underlying mechanisms. This study aimed to examine the mediating role of cancer patients' illness perceptions in the relations between self-compassion and psychological symptoms. Methods This cross-sectional study focused on 301 people with heterogeneous types of cancer. A self-reported questionnaire was used to collect participants' levels of self-compassion, illness perceptions, and symptoms of depression and anxiety. Parallel mediation analyses were performed to examine the research questions. Results The relation between self-compassion and depressive symptoms was mediated by perceived consequences and a timeline cyclical of cancer. Perceived consequences also mediated the relation between self-compassion and symptoms of anxiety, with an additional mediating role of personal control. Conclusions These findings suggest that both self-compassion and illness perceptions were closely linked with cancer patients' psychological symptoms. Particularly, cancer patients who feel more self-compassionate perceive fewer negative consequences of cancer, a less timeline cyclical, and more personal control over their life and report fewer psychological symptoms.

OBJECTIVES: The protective role of self-compassion in cancer patients' psychological outcomes has been confirmed. However, using a composite score of self-compassion, previous research could not clarify how distinct components of self-compassion may mutually interact. This study, using a person-centred approach, aimed to identify profiles of self-compassion in cancer patients and examined the associations of self-compassion profiles with sociodemographic and medical variables and psychological outcomes.METHODS: This cross-sectional study included 289 patients with heterogeneous cancer types recruited from two hospitals in Xi'an, China. Latent profile analysis was used to identify distinct profiles of self-compassion. The Bolck-Croon-Hagenaars approach was used to examine how these profiles related to sociodemographic and medical characteristics and psychological outcomes.RESULTS: Five profiles of self-compassion were identified: 'average self-compassion' (54%), 'high self-compassion' (19.4%), 'low self-compassion and low self-coldness' (11.4%), 'high self-compassion and high self-coldness' (8%), and 'average self-compassion and high self-coldness' (7.2%). Patients with the 'high self-compassion' profile tended to be older and report no cancer recurrence, and those with the 'low self-compassion and low self-coldness' profile tended to be female. Patients with the 'high self-compassion' profile reported the fewest depressive and anxiety symptoms while patients with the 'average self-compassion and high self-coldness' profile reported the most depressive and anxiety symptoms.CONCLUSIONS: The study revealed five self-compassion profiles in cancer patients, which had different psychological outcomes. Future longitudinal research should investigate the causality between self-compassion profiles and psychological outcomes.

Recent years have witnessed evolutions of topologies and applications in electric vehicles. Many international standards such as CISPR 25 are designed to protect on-board devices from disturbances caused by radiated emissions arising in a vehicle. This paper investigates the radiated EMI (RE) caused by a buck-boost power converter in the 150kHz to 30MHz frequency range. Based on the developed emission noise model, the switching noise voltage is applied across the inductor, and it is identified as the main emission noise source. The lumped charge model is proposed to analyze the E field in the space due to a coil and the impact of dielectric medium is investigated using electrostatic theory. Experiments for near electric field emission measurement and RE measurement are conducted to identify the noise source and the analysis is verified in simulation.

For the radiated electromagnetic interference pre-compliance diagnosis in power electronics systems, the measurement of common mode (CM) currents, impedances, and voltages are essentially important. In this article, two measurement issues are first identified in CM current and impedance measurement. The first is the coupling between the cables attached to a power converter and the coaxial cable connected to the measurement equipment. It degrades the measurement accuracy. The second is the coupling between the converter's attached cables and the ac grid. It degrades the repeatability of measurements. To improve the measurement accuracy and repeatability, this article proposes an improved measurement technique to address these two issues. Furthermore, for the measurement of the voltage difference between primary and secondary grounds, this article also identifies two issues. The first is the poor measurement resolution for the low noise voltage in the high-frequency range due to the high magnitude of line-frequency voltages. The second is that the loading effects of the voltage probe can reduce the measurement accuracy. This article proposed a technique to address these two issues. Finally, the proposed measurement techniques were validated on a flyback converter.

Electromagnetic interference (EMI) issue becomes a headache problem when the switching frequency has been pushed higher and higher for the smaller size and higher power density. Up to now, the conducted EMI can be controlled very well with decades of exploration and research. However, the radiated EMI is still hard to be understood and controlled, the techniques to reduce the radiated EMI are limited. In this paper, active-clamp flyback converters are taken as the example, the radiation model is developed, the double shielding technique is proposed to mitigate the radiated EMI effectively no matter the EMI filters are placed on the AC line or DC bus. The concept of this technique is explained in detail, the experiments are conducted to verify the analysis. The guideline to choose the appropriate connection method of the double shielding technique is given for both the AC line and DC bus EMI filters.

Radiated electromagnetic interference (EMI) is an important and challenging topic in modern power electronics. To analyze radiated EMI, modeling research is the foundation. Modeling research can reveal fundamental mechanisms including switching noise generation, noise conversion into the radiation excitation, antenna characteristics, and near field couplings’ impact. Radiated EMI models are developed. Based on radiated EMI modeling research, noise reduction techniques are developed, including component improvement, printed circuit board (PCB) layout improvement, high-frequency EMI filters, and shielding. This paper summarizes recent research advances and discusses future radiated EMI challenges and research topics.

This paper investigates noise spectrums and radiated EMI in high-frequency gallium nitride (GaN) integrated circuit (IC)-based active clamp flyback (ACF) converters. Influential factors for the noise spectrums are investigated, including the switching frequency, dv/dt and waveform symmetry, voltage magnitude, duty cycle, etc. Moreover, in the radiated EMI frequency range, the relationship between spectrum valleys and dv/dt is analyzed. In the investigated GaN IC-based ACF, the voltage spectrums and radiated EMI with high line and low line input voltages are analyzed and investigated experimentally.

Electromagnetic interference (EMI) in non-isolated power converters is regulated by extensive standards in many applications. EMI modeling and reduction research is key to develop solutions to achieve EMI compliance. For conducted EMI, there are lots of techniques to analyze noise sources, propagation paths, parasitic couplings, and so on, which are summarized in this survey. Fundamental and general techniques to investigate and to reduce conducted EMI are analyzed. Moreover, in the high switching frequency era and with increasing applications of wide bandgap devices, radiated EMI is becoming an inevitable challenge. Modeling and reduction of radiated EMI, therefore, is becoming an important topic. Recent advances in radiated EMI research for non-isolated power converters are summarized and analyzed. Future EMI research development is discussed.

The magnetic core plays a very important role in high frequency switching transformer modeling, design as well as loss estimation, etc. Extract the core loss from the winding loss accurately is essential in many industrial applications. Usually, A power amplifier connected to a function generator is applied to add the excitation to the CUT (core under test). For practical applications, sometimes, a square-wave or triangular-wave excitation, which depends on the working condition, is required to be added to the CUT. However, sometimes, it is found the non-sinusoidal excitations added on the CUT are distorted, which brings difficulties to accurate core loss measurement. In this paper, a detailed explanation for this phenomenon is given, several convenient solutions to improve the non-sinusoidal waveforms are explored based on the theoretical analysis. Both the simulation and experiment verify the analysis.

Power converter layout is a critical factor for the radiated EMI. Because the radiation excitation is generated by the power converter and it is significantly influenced by the layout. The power converter layout includes the component location and the PCB trace layout. This paper develops noise modeling techniques to reveal the mechanisms of the layout’s influences. And based on the modeling researches, layout improvement guidelines for reducing the radiated EMI are produced, including the component location improvement, and the PCB layout improvement. Experimental verifications including the semi-anechoic chamber testing are conducted on a buck-boost power converter and on a buck power converter in automotive applications.

Objective This study aimed to examine (1) The courses of Chinese cancer patients' unmet supportive care needs (psychological, physical and daily living, health system and information, patient care and support, and sexual) from the first cancer diagnosis until the end of medical treatment; (2) The predictive role of socio-demographic and medical characteristics (i.e., age, gender, and cancer stage) in the courses of unmet needs; and (3) The associations of courses of unmet needs with courses of depressive and anxiety symptoms. Methods A longitudinal study was performed at Shaanxi Provincial Tumour Hospital in Xi'an, China. A total of 153 heterogeneous cancer patients were assessed after the first diagnosis (T1), at the beginning (T2) and the end (T3) of the receipt of medical treatment. Latent growth curve models were used to examine the research questions. Results Psychological needs and health system and information needs showed a decrease over time, whereas physical needs, patient care needs and sexual needs remained stable. Younger and female patients tended to report higher levels of unmet psychological needs at T1 and experienced slower decreases from T1 to T3. Only the courses of unmet psychological needs were associated with the courses of depressive and anxiety symptoms from T1 to T3. Conclusions More attention can be given to young and female cancer patients, as they were more likely to suffer from high unmet psychological needs over the disease trajectory. Future research may focus more on addressing unmet needs reported by Chinese cancer patients.

For power converters in automotive applications, near field couplings can lead to radiated electromagnetic interference (EMI). This paper develops a radiated EMI model to characterize near field coupling’s impact on the radiated EMI. Influential factors of near field couplings and power converter’s parasitic inductances are analyzed. Based on the developed model, noise reduction techniques are proposed, including capacitor layout improvement and CM choke implementation improvement. Experiments verify the developed model and the proposed noise reduction techniques.

Recent years have witnessed evolutions of topologies and applications of wide bandgap devices in flyback converters, in order to improve efficiency and power density. However, due to the increased topology diversity, and the increased high frequency noise, unprecedented EMI challenges are created. Those challenges lead to advances of EMI modeling and reduction techniques, to be generalized for different topologies, and to be effective at higher frequency ranges. The emerging flyback EMI challenges and research advances are analyzed in this paper. Future challenges and development of EMI in flyback converters are discussed.

This paper investigates radiated electromagnetic interference (EMI) causes and solutions in high-frequency active-clamp flyback (ACF) using GaN ICs. GaN devices enable high-frequency operation which shrinks the passive component size and can potentially be more efficient. However, the increased spectrum of radiated EMI is a concern with a lack of readily-available solutions. This paper analyzes noise mechanisms by studying waveform and spectrum compositions, identifying major noise contributors. Near field couplings of the cable-converter electric couplings are identified as inducing the CM noise and bypassing the CM choke. This paper develops models to characterize the near field coupling effects on the radiated EMI. Noise reduction techniques including a shielding and grounding technique, a CLC pi-type CM filter are proposed and verified. Experimental verifications are performed on a GaN IC-based ACF power adapter and radiated EMI is brought into compliance.

This paper develops modeling and reduction techniques of the radiated electromagnetic interference (EMI) in non-isolated power converters in automotive applications. In modeling investigations, noise source models and the antenna models are developed to reveal the generation of the common mode (CM) noise and the radiated EMI in the investigated buck-boost power converter. The developed models can predict the radiated EMI with clear physical meanings of the switching noise, the power converter topology, and the PCB parasitics. The influences of the PCB ground layer parasitics on the radiated EMI are first revealed. In noise reduction investigations, several techniques are proposed including 1) PCB layout improvement for reducing the parasitics of the ground layer and 2) circuit topology improvement including the addition of a capacitor across the input and output nodes and improvement of the PCB traces connecting the cross capacitor. Experimental verifications of the radiated modeling and reduction techniques are conducted on a buck-boost power converter in automotive lighting applications.

Objectives This study aimed to (1) identify distinct patterns of unmet needs in Chinese cancer patients; (2) examine whether socio-demographic and medical characteristics distinguished these patterns; and (3) examine whether people with distinct patterns reported differential Quality of Life (QoL). Methods This cross-sectional study recruited 301 cancer patients from two hospitals in China. The 34-item Supportive Care Needs Survey Short-Form was used to measure unmet needs across five domains: physical and daily living, psychological, patient care and support, health systems and information, and sexuality. Latent class analysis was performed to identify patterns of unmet needs across these domains. Results Four patterns of unmet needs were identified, differing in levels and nature of unmet needs. Participants in Class 1 (47%) reported few unmet needs. Patients in Class 2 (15%) had moderate levels of unmet needs, displaying similar levels across five domains. People in Class 3 (25%) and Class 4 (13%) reported similarly high levels on “psychological”, “health care system and information”, “physical and daily living” and “patient care”, but differing in “sexuality”, with Class 3 reporting low levels while Class 4 high on “sexuality”. None of socio-demographic and medical characteristics distinguished these patterns significantly. Compared to other classes, people in Class 1 reported highest levels of QoL. Conclusions This study demonstrates the existence of four patterns of unmet supportive needs in Chinese cancer patients. Patients with few unmet needs reported the best QoL.

Objective Self-compassion is consistently found to be related to better psychological outcomes. As most studies were cross-sectional, little is known about the predictive role of self-compassion for future psychological outcomes. This longitudinal study in cancer patients investigated the predictive role of self-compassion at the time of cancer diagnosis for the course of symptoms of depression, anxiety, and fatigue in the period of receiving cancer treatment. Methods This longitudinal study was conducted at the Shaanxi Provincial Tumour Hospital in Xi'an, China. A total of 153 heterogeneous cancer patients were assessed within 1 week after cancer diagnosis (T1) as well as at the start (T2) and the end (T3) of medical treatment. Hierarchical linear regression analyses were conducted to examine the research questions. Results Cross-sectional regression analyses at T1 showed that a self-compassion total score and negative self-compassion (and to a lesser extent positive self-compassion) were significantly related to symptoms of depression, anxiety, and fatigue. When controlling for symptoms at T1, positive self-compassion significantly predicted all three outcomes at T3. A self-compassion total score only predicted symptoms of anxiety at T2, controlling for T1 symptoms. In contrast, we found no significant predictive value of negative self-compassion. Conclusions This study suggests that the positive aspects of self-compassion are beneficial for cancer patients for their future functioning, in terms of fewer symptoms of depression, anxiety, and fatigue over time. Future interventions should test how and to what extent self-compassion can be cultivated and whether increases in self-compassion are associated with better outcomes.

This paper investigates the radiated electromagnetic interference (EMI) in non-isolated power converters for automotive applications. The radiated EMI is mainly caused by the cable antenna radiation. The mechanism of the cable antenna radiation is the common mode (CM) noise propagating through the power cables and radiating to space. The radiation excitation noise is generated by the non-isolated power converter. Through the noise circuit of the non-isolated power converter, the initial switching noises transform to the radiation excitation source. To develop the model for characterizing the generation of the radiation excitation source, this paper analyzes the noise circuit and the noise transformation in the non-isolated power converter. And based on the analyses of the noise circuit, this paper investigates the critical parasitics in the non-isolated power converter. Simulation and experimental investigations of the radiated EMI and the noise sources are conducted.

The paper evaluates the equivalent parasitic capacitance and the equivalent parasitic resistance of a typical toroid inductor with Mn-Zn ferrite core based on the analysis of the electric field energy in the magnetic core and the space. The high frequency impedance can be increased based on the reduction of the total electric field energy. Several techniques, such as optimizing the dimension of the magnetic core, applying stacked cores, modifying winding turn number and improving the winding structure are introduced to improve the high frequency impedance of the ferrite toroid inductors. FEA simulation and experiments verify the theory and techniques.

Magnetic cores are essentially significant in high frequency switching transformers. The core loss is an important characteristic parameter of the switching transformer modeling, loss estimation and thermal design, etc. Therefore, it is essential to measure the core loss accurately. In this paper, a brief review about the existing core loss measurement methods under arbitrary excitation is given. The accuracy and applicability of each method are discussed theoretically and verified experimentally, especially at high frequencies up to several MHz. The paper provides appropriate core loss measurement methods in different situations for both scholars and engineers.

In power converters, common mode (CM) noise can radiate to cause radiated electromagnetic interference (EMI). Resistive, inductive and capacitive parts of the CM inductors can interact with the antenna to induce damping effect or additional resonance. The resistive component is desired for radiated EMI reduction with resonance avoided and noise energy dissipated. This paper researches on the equivalent core loss resistance and its application on CM inductors for radiated EMI reduction. This paper investigates the equivalent core loss resistance and quantifies its relation with core parameters and winding parameters. Critical factors for the equivalent core loss resistance include the ratio of core’s cross section area over core’s magnetic path length and winding’s turns number. Capacitive part of the CM inductor is also considered given its influence on impedance and on radiated EMI. Parasitic capacitances of both the winding and the core are analyzed. Experimental verification on the core loss based CM inductor design is performed on a flyback converter, with radiated EMI measured in a semi-anechoic chamber.

Transformer modeling is important for EMI prediction and suppression. Existing modeling techniques only focus on either differential mode (DM) model or common mode (CM) model. However, these models are inaccurate for high-frequency range above 10MHz. This paper proves that the inaccuracy is mainly due to the current coupling between DM path and CM path. This paper proposes a simple physical model. It also quantifies how the DM components can influence the CM impedance and how the CM parasitic components can influence the DM impedance. The effects of different ground connections can also be analyzed with the model. Experimental results verify that the proposed model is accurate within both conducted and radiated frequency ranges from 150 kHz to 100 MHz.

Power converters should comply with the radiated emission regulation standards. For isolated power converters with long input / output cables, radiated EMI is mostly caused by the CM currents. Accurate and repeatable measurement for the radiated CM currents, impedance and voltages remains a fundamental challenge to the EMI/EMC research in power electronics. In this paper, two measurement issues in the CM current and CM impedance measurement are identified. They are the coupling between the equipment under test (EUT) and the measurement equipment, and the influence of the varying utility grid impedance. Based on the radiated CM current model, this paper proposes improved measurement techniques. By increasing the CM impedances of the measurement equipment cables and the cable connecting the utility grid, the undesired coupling can be eliminated and the utility grid impedance can be isolated. Furthermore, the issues in the CM voltage measurement are identified: low resolution for the low voltage component in the radiated frequency range due to the high magnitude fundamental frequency voltage component; and the small input impedance of the high pass filter which can bypass the radiated emission of the EUT. This paper proposes an improved measurement technique to improve the resolution of voltage measurement in the radiated frequency range and to isolate the input impedance of the high pass filter. Effectiveness and accuracy of the proposed measurement techniques are verified through experiments performed on a flyback converter with input and output long cables.

The growth of Irpex lacteus F17 and manganese peroxidase (MnP) production in a selfdesigned tray bioreactor, operating in solid-state conditions at a laboratory scale, were studied. The bioreactor was divided into three layers by three perforated trays. Agroindustrial residues were used both as the carrier of bound mycelia and as a nutrient medium for the growth of I. lacteus F17. The maximum biomass production in the bioreactor was detected at 60 h of fermentation, which was consistent with the CO2 releasing rate by the fungus. During the stationary phase of fungal growth, the maximum MnP activity was observed, reaching 950 U/l at 84 h. Scanning electron microscopy images clearly showed the growth situation of mycelia on the support matrix. Furthermore, the MnP produced by I. lacteus F17 in the bioreactor was isolated and purified, and the internal peptide sequences were also identified with mass spectrometry. The optimal activity of the enzyme was detected at pH 7 and 25 °C, with a long half-life time of 9 days. In addition, the MnP exhibited significant stability within a broad pH range of 4-7 and at temperature up to 55 °C. Besides this, the MnP showed the ability to decolorize the polymeric model dye Poly R-478 in vitro.

The production of ligninolytic enzymes by the fungus Schizophyllum sp. F17 using a cost-effective medium comprised of agro-industrial residues in solid-state fermentation (SSF) was optimized. The maximum activities of the enzymes manganese peroxidase (MnP), laccase (Lac), and lignin peroxidases (LiP) were 1,200, 586, and 109 U/L, respectively, on day 5 of SSF. In vitro decolorization of three structurally different azo dyes by the extracellular enzymes was monitored to determine its decolorization capability. The results indicated that crude MnP, but not LiP and Lac, played a crucial role in the decolorization of azo dyes. After optimization of the dye decolorization system with crude MnP, the decolorization rates of Orange IV and Orange G, at an initial dye concentration of 50 mg/L, were enhanced to 76 and 57%, respectively, after 20 min of reaction at pH 4 and 35°C. However, only 8% decolorization of Congo red was observed. This enzymatic reaction system revealed a rapid decolorization of azo dyes with a low MnP activity of 24 U/L. Thus, this study could be the basis for the production and application of MnP on a larger scale using a low-cost substrate.

The novel hybrid cascaded multilevel converter, with partial regenerative cells supplied by bidirectional rectifiers, is cost effective to recover the regenerative energy. To apply it in industrial fields containing various motors with loads, a systematic scheme designing the power cells is indispensable. This paper reveals that the maximum power factor angle of the motor is determined by the deceleration velocity, and that the controllable domain of the converter is determined by the sum of the DC voltage of the regenerative cells. From these analyses derives a step-by-step designing scheme. Furthermore, the scheme is optimized to reduce the regenerative cells, so as to be more cost effective. The results of simulation and experiment demonstrate that the optimized scheme can enable the converter to cost effectively recover the regenerative energy.

This paper proposes a novel composite cascaded multilevel inverter, of which uncontrolled converters and pulse-width modulation (PWM) converters are connected in parallel. The proposed composite inverter could reduce the cost as compared with the pure PWM inverter, realize energy two-way flow and simplify the structure design of the phase shifting transformer. This paper adopts bypass control strategy to make the renewable energy wholly fed back through the PWM power units. To verify the proposed technique, this paper designs a three-phase cascaded multilevel medium-voltage inverter composed by five cascaded units, of which three are energy feedback units. Investigations using MATLAB/Simulink based simulations and an experimental prototype confirm the practicability and validity of the proposed technique.