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1.
Life (Basel) ; 14(5)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38792592

RESUMO

(1) Background: Children are the most vulnerable to pollution due to their decreased stature, heightened respiratory rate, and frequent outdoor engagement. PM2.5, nitrogen dioxide (NO2), ozone, and cold weather are associated with pediatric asthma. In this study, we investigated the nexus between air pollution, climate factors, and pediatric asthma emergency room visits (ERVs). (2) Method: Pediatric asthma ERV data for healthcare quality from the Taiwanese National Insurance in the Taipei area were obtained from 2015 to 2019. Air pollution and climate factor data were also collected. Poisson regression was employed to determine the relationships with relative risks (RRs). (3) Results: The incidence of pediatric asthma ERVs decreased, with a crude RR of 0.983 (95% CI: 0.98-0.986, p < 0.001). Fine particulate matter (PM2.5) had an adjusted RR of 1.102 (95% CI: 1.037-1.172, p = 0.002) and a 7.7 µg/m3 increase, and air temperature had an adjusted RR of 0.813 (95% CI: 0.745-0.887, p < 0.001) comparing between the highest and lowest quarter air temperature associated with pediatric asthma ERVs. (4) Conclusions: This inquiry underscores the positive associations of PM2.5 and cold weather with pediatric asthma ERVs. The findings could guide the government to establish policies to reduce air pollution and promote children's health.

2.
PeerJ ; 12: e17229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618561

RESUMO

Background: Current drugs for treating osteoporosis may lead to toxic side effects. Echinacoside (ECH) is a natural small molecule drug. This study examined and compared the therapeutic effects of cross-linker (CL)-ECH and ECH-free nanoparticles on osteoporosis. Methods: Echinocandin-based CL-ECH nanoparticles were prepared, and the nanoparticle size and drug loading were optimized and characterized by adjusting the ratio. The antioxidant effect of CL-ECH nanoparticles on bone marrow-derived macrophages (BMDMs) was analyzed using flow cytometry, immunofluorescence staining and quantitative real-time polymerase chain reaction (qRT-PCR). Bone marrow stromal cells (BMSCs)-based detection of bone-producing effects was conducted using alkaline phosphatase (ALP), Alizarin Red S (ARS) and qRT-PCR. TRAP, phalloidin staining, and qRT-PCR was performed to detect osteogenesis-inhibiting effect on BMDMs. CL-ECH nanoparticles were applied to treat an ovariectomized (OVX) mouse model at low doses. Results: Compared to ECH, CL-ECH nanoparticles suppressed oxidative stress in BMDMs by promoting NRF-2 nuclear translocation, which inhibited the production of both reactive oxygen species (ROS) and osteoclast production through downregulating NF-κB expression, with limited effect on the osteogenesis of BMSCs. In vivo studies showed that low-dose CL-ECH nanoparticles markedly improved bone trabecular loss compared to ECH administration in the treatment of osteoporosis. Conclusions: The current discoveries provided a solid theoretical foundation for the development of a new generation of anti-bone resorption drugs and antiosteoporosis drugs.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , Animais , Camundongos , Osteoporose/tratamento farmacológico , Glicosídeos/farmacologia , Fosfatase Alcalina
3.
J Transl Med ; 22(1): 345, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600566

RESUMO

BACKGROUND: Hearing loss has been shown to be a risk factor for psychiatric disorders. In addition, long-term hearing loss is associated with increased hospitalization and mortality rates; however, the increased risk and duration of effect of hearing loss in combination with other chronic diseases on each psychiatric disorder are still not clearly defined. The purpose of this article is to clarify the risk of hearing loss for each disorder over time. METHODS: This was a retrospective cohort study, and a national health insurance research database in Taiwan was utilized. All (n = 1,949,101) Taiwanese residents who had a medical visit between 2000 and 2015 were included. Patients with hearing loss and a comparative retrospective cohort were analyzed. Every subject was tracked individually from their index date to identify the subjects who later received a diagnosis of a psychiatric disorder. The Kaplan‒Meier method was used to analyze the cumulative incidence of psychiatric disorders. Cox regression analysis was performed to identify the risk of psychiatric disorders. RESULTS: A total of 13,341 (15.42%) and 31,250 (9.03%) patients with and without hearing loss, respectively, were diagnosed with psychiatric disorders (P < 0.001). Multivariate analysis indicated that hearing loss significantly elevated the risk of psychiatric disorders (adjusted HR = 2.587, 95% CI 1.723-3.346, p < 0.001). CONCLUSION: Our findings indicate that patients with hearing loss are more likely to develop psychiatric disorders. Furthermore, the various psychiatric disorders are more likely to occur at different times. Our findings have important clinical implications, including a need for clinicians to implement early intervention for hearing loss and to pay close attention to patients' psychological status. Trial registration TSGHIRB No. E202216036.


Assuntos
Perda Auditiva , Transtornos Mentais , Humanos , Estudos de Coortes , Perda Auditiva/complicações , Perda Auditiva/epidemiologia , Incidência , Transtornos Mentais/complicações , Transtornos Mentais/epidemiologia , Fatores de Risco , Taiwan/epidemiologia
4.
Medicina (Kaunas) ; 60(3)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38541231

RESUMO

Background and Objectives: The coronavirus disease 2019 (COVID-19) pandemic originated in Wuhan, China, in December 2019, the first case diagnosed since January 2020 in Taiwan. The study about the potential impact of the COVID-19 pandemic on event, location, food source, and pathogens of foodborne disease (FBD) is limited in Taiwan. Our aim in this study is to investigate FBD in the context of the COVID-19 pandemic. Materials and Methods: We collected publicly available annual summary data from the FBD dataset in the Taiwan Food and Drug Administration and Certifiable Disease on reported FBD in Taiwan from 2019 to 2020. We used logistic regression to evaluate changes in the occurrence or likelihood of FBD cases and Poisson regression to examine the relative risk (RR) between FBD and climate factors. Results: Similar events occurred in 2019 and 2020, but the total number of FBD cases decreased from 6935 in 2019 to 4920 in 2020. The places where FBD decreased were in schools, hospitals, outdoors, vendors, and exteriors. The top place in FBD shifted from schools to restaurants. The top food source for FBD has changed from boxed food to compound food. Bacillus cereus and Salmonella emerged as the top two observed bacterial pathogens causing FBD. The risk of FBD cases increased with a higher air temperature, with an RR of 1.055 (1.05-1.061, p < 0.001) every 1 °C. Conclusion: The incidence of FBD decreased significantly during the COVID-19 pandemic in Taiwan. This decline may be attributed to protective measures implemented to control the spread of the virus. This shift in locations could be influenced by changes in public behavior, regulations, or other external factors. The study emphasizes the importance of understanding the sources and effectiveness of severe infection prevention policies. The government can use these findings to formulate evidence-based policies aimed at reducing FBD cases and promoting public health. Consumers can reduce the risk of FBD by following safe food handling and preparation recommendations.


Assuntos
COVID-19 , Doenças Transmitidas por Alimentos , Humanos , COVID-19/epidemiologia , Pandemias , Taiwan/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Saúde Pública
5.
Toxics ; 12(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38251034

RESUMO

(1) Background: An asthma exacerbation that is not relieved with medication typically requires an emergency room visit (ERV). The coronavirus disease 2019 (COVID-19) pandemic began in Taiwan in January of 2020. The influence of the COVID-19 pandemic on pediatric ERVs in Taiwan was limited. Our aim was to survey pediatric asthma ERVs in the COVID-19 era; (2) Methods: Data were collected from the health quality database of the Taiwanese National Health Insurance Administration from 2019 to 2021. Air pollution and climatic factors in Taipei were used to evaluate these relationships. Changes in the rates of pediatric asthma ERVs were assessed using logistic regression analysis. Poisson regression was used to evaluate the impact of air pollution and climate change; (3) Results: The rate of pediatric asthma ERVs declined in different areas and at different hospital levels including medical centers, regional and local hospitals. Some air pollutants (particulate matter ≤ 2.5 µm, particulate matter ≤ 10 µm, nitrogen dioxide, and carbon monoxide) reduced during the COVID-19 lockdown. Ozone increased the relative risk (RR) of pediatric asthma ERVs during the COVID-19 period by 1.094 (95% CI: 1.095-1.12) per 1 ppb increase; (4) Conclusions: The rate of pediatric asthma ERVs declined during the COVID-19 pandemic and ozone has harmful effects. Based on these results, the government could reduce the number of pediatric asthma ERVs through healthcare programs, thereby promoting children's health.

6.
Acta Biomater ; 173: 442-456, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37984632

RESUMO

Osteoporosis (OP), which largely increases the risk of fractures, is the most common chronic degenerative orthopedic disease in the elderly due to the imbalance of bone homeostasis. Alpha-ketoglutaric acid (AKG), an endogenous metabolic intermediate involved in osteogenesis, plays critical roles in osteogenic differentiation and mineralization and the inhibition of osteoclastogenic differentiation. However, the low bioavailability and poor bone-targeting efficiency of AKG seriously limit its efficacy in OP treatment. In this work, a bone-targeting, near-infrared emissive lanthanide luminescence nanocarrier loaded with AKG (ß-NaYF4:7%Yb, 60%Nd@NaLuF4@mSiO2-EDTA-AKG, abbreviated as LMEK) is developed for the enhancement of AKG efficacy in OP therapy. By utilizing the NIR-II luminescence (>1000 nm) of LMEK, whole-body bone imaging with high spatial resolution is achieved to confirm the bone enrichment of AKG noninvasively in vivo. The results reveal that LMEK exhibits a remarkable OP therapeutic effect in improving the osseointegration of the surrounding bone in the ovariectomized OP mice models, which is validated by the enhanced inhibition of osteoclast through hypoxia-inducible factor-1α suppression and promotion of osteogenic differentiation in osteoblast. Notably, the dose of AKG in LMEK can be reduced to only 0.2 % of the dose when pure AKG is used in therapy, which dramatically improves the bioavailability of AKG and mitigates the metabolism burden. This work provides a strategy to conquer the low utilization of AKG in OP therapy, which not only overcomes the challenges in AKG efficacy for OP treatment but also offers insights into the development and application of other potential drugs for skeletal diseases. STATEMENT OF SIGNIFICANCE: Alpha-ketoglutarate (AKG) is an intermediate within the Krebs cycle, participating in diverse metabolic and cellular processes, showing potential for osteoporosis (OP) therapy. However, AKG's limited bioavailability and inefficient bone-targeting hinder its effectiveness in treating OP. Herein, a near-infrared emissive nanocarrier is developed that precisely targets bones and delivers AKG, bolstering its effectiveness in OP therapy. Thanks to this efficient bone-targeting delivery, the AKG dosage is reduced to 0.2 % of the conventional treatment level. This marks the first utilization of a bone-targeting nanocarrier to amplify AKG's bioavailability and OP therapy efficacy. Furthermore, the mechanism of AKG-loaded nanocarrier regulating the biological behavior of osteoclasts and osteoblasts mediated is tentatively explored.


Assuntos
Ácidos Cetoglutáricos , Osteoporose , Humanos , Camundongos , Animais , Idoso , Ácidos Cetoglutáricos/farmacologia , Ácidos Cetoglutáricos/metabolismo , Ácidos Cetoglutáricos/uso terapêutico , Osteogênese , Luminescência , Osteoporose/tratamento farmacológico , Osteoblastos/metabolismo
7.
Healthcare (Basel) ; 11(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37957996

RESUMO

BACKGROUND: In situ simulation is the practice of using simulated scenarios to improve skill implementation, train critical thinking and problem-solving abilities, and enhance self-efficacy. This study aimed to enhance nursing knowledge, skills, and attitudes toward clinical work by applying in situ simulation training to improve the healthcare of critically ill patients. METHODS: This study was conducted from a medical center in northern Taiwan and included 86 trainees who received intensive care training courses from 1 June 2017 to 31 May 2019. The self-report knowledge assessment, empathetic self-efficacy scale, skill assessment, and attitudes of instructors before and after training were collected. The statistical analysis used the Wilcoxon test for knowledge and attitudes, and chi-square tests were used for skills to evaluate the learning effect. RESULTS: The results showed a statistically significant improvement in knowledge, skills, attitudes, and empathy in nursing care. CONCLUSIONS: In situ simulation learning can be an accepted method for nursing skills in the intensive care unit. Through this study, we understood that the in situ simulation method was beneficial to nurses' care and care thinking processes. It is worth developing and evaluating integrated simulation education to enhance learning, change behavior, and promote holistic care in the nursing field.

8.
Medicina (Kaunas) ; 59(11)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-38003946

RESUMO

Background and Objectives: Hearing loss after septicemia has been found in mice; the long-term risk increased 50-fold in young adults in a previous study. Hearing loss after septicemia has not received much attention. The aim of this study was to assess the relationship between septicemia and subsequent hearing loss. Materials and Methods: Inpatient data were obtained from the Taiwan Insurance Database. We defined patients with sensorineural hearing loss and excluded patients under 18 years of age. Patients without hearing loss were selected as controls at a frequency of 1:5. The date of admission was defined as the date of diagnosis. Comorbidities in the 3 years preceding the date of diagnosis were retrieved retrospectively. Associations with hearing loss were established by multiple logistic regression and forward stepwise selection. Results: The odds ratio (OR) for the association between sepsis and hearing loss was 3.052 (95% CI: 1.583-5.884). Autoimmune disease (OR: 5.828 (95% CI: 1.906-17.816)), brain injury (OR: 2.264 (95% CI: 1.212-4.229)) and ischemic stroke (OR: 1.47 (95% CI: 1.087-1.988)) were associated with hearing loss. Conclusions: Our study shows that hearing loss occurred after septicemia. Apoptosis caused by sepsis and ischemia can lead to hair cell damage, leading to hearing loss. Clinicians should be aware of possible subsequent complications of septicemia and provide appropriate treatment and prevention strategies for complications.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Sepse , Adulto Jovem , Humanos , Animais , Camundongos , Adolescente , Estudos Retrospectivos , Fatores de Risco , Comorbidade , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/epidemiologia , Sepse/complicações , Sepse/epidemiologia
9.
Micromachines (Basel) ; 14(10)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37893343

RESUMO

Piezoelectric ceramic actuators utilize an inverse piezoelectric effect to generate high-frequency vibration energy and are widely used in ultrasonic energy conversion circuits. This paper presents a novel drive circuit with input-current shaping (ICS) and soft-switching features which consists of a front AC-DC full-wave bridge rectifier and a rear DC-AC circuit combining a stacked boost converter and a half-bridge resonant inverter for driving a piezoelectric ceramic actuator. To enable ICS functionality in the proposed drive circuit, the inductor of the stacked boost converter sub-circuit is designed to operate in boundary-conduction mode (BCM). In order to allow the two power switches in the proposed drive circuit to achieve zero-voltage switching (ZVS) characteristics, the resonant circuit of the half-bridge resonant inverter sub-circuit is designed as an inductive load. In this paper, a prototype drive circuit for providing piezoelectric ceramic actuators was successfully implemented. Experimental results tested at 110 V input utility voltage show that high power factor (PF > 0.97), low input current total harmonic distortion (THD < 16%), and ZVS characteristics of the power switch were achieved in the prototype drive circuit.

10.
Healthcare (Basel) ; 11(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570356

RESUMO

(1) Background: Patients who are critically ill or undergo major surgery are admitted to intensive care units (ICUs). Prolonged immobilization is the most likely cause of pressure injuries (PrIs) in the ICU. Previous studies of Western populations found that effective protocols could reduce the incidence of PrIs, and the efficacy of systemic targeted intervention protocols in preventing PrIs in the Chinese population needs to be surveyed. (2) Methods: We reviewed cases of PrIs in the ICUs of Taipei Veterans General Hospital from 2014 to 2019. The ICU nurses at the hospital began to implement targeted interventions in January 2017. The incidence density of PrIs was calculated by dividing the number of PrIs by person days of hospitalizations in the pre-bundle (2014-2016) and post-bundle (2017-2019) stages. Poisson regression was performed to compare the trend of incidence densities. (3) Results: The incidence density of PrIs was 9.37/1000 person days during the pre-bundle stage and 1.85/1000 person days during the post-bundle stage (p < 0.001). The relative risk (RR) was 0.197 (95% confidence interval: 0.149-0.26). The incidence densities of iatrogenic PrIs and non-iatrogenic PrIs decreased as the RRs decreased. (4) Conclusions: Targeted interventions could significantly reduce the incidence of PrIs. Healthcare providers must follow the bundle care protocol for PrI prevention to improve the quality of healthcare and promote patient health.

11.
J Pers Med ; 13(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37109009

RESUMO

(1) Background: Intravenous thrombolysis following acute ischemic stroke (AIS) can reduce disability and increase the survival rate. We designed a functional recovery analysis by using semantic visualization to predict the recovery probability in AIS patients receiving intravenous thrombolysis; (2) Methods: We enrolled 131 AIS patients undergoing intravenous thrombolysis from 2011 to 2015 at the Medical Center in northern Taiwan. An additional 54 AIS patients were enrolled from another community hospital. A modified Rankin Score ≤2 after 3 months of follow-up was defined as favorable recovery. We used multivariable logistic regression with forward selection to construct a nomogram; (3) Results: The model included age and the National Institutes of Health Stroke Scale (NIHSS) score as immediate pretreatment parameters. A 5.23% increase in the functional recovery probability occurred for every 1-year reduction in age, and a 13.57% increase in the functional recovery probability occurred for every NIHSS score reduction. The sensitivity, specificity, and accuracy of the model in the validation dataset were 71.79%, 86.67%, and 75.93%, respectively, and the area under the receiver operating characteristic curve (AUC) was 0.867; (4) Conclusions: Semantic visualization-based functional recovery prediction models may help physicians assess the recovery probability before patients undergo emergency intravenous thrombolysis.

12.
Toxics ; 11(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36850970

RESUMO

(1) Background: The acute effects of ozone, cold temperature and particulate matter less than 2.5 µm (PM2.5) in size related to asthma attacks are well known worldwide. The adverse effects of ozone and cold temperature on asthma morbidity in Taiwan are still inconclusive. (2) Methods: This retrospective study included patients who had asthma emergency room visits (ERVs) from 1 January 2016 to 31 December 2019 in a regional hospital in Taiwan. The short-term negative effects were estimated using Distributed Lag Non-Linear Models (DLNMs) for the relative risks (RRs) of asthma ERVs associated with PM2.5, ozone and cold temperature exposures within 5 days. (3) Results: There was a significant association between a 10 ppm increase in PM2.5 exposure and asthma ERVs at a 2-day lag (RR 1.166, 95% confidence interval (C.I.): 1.051-1.294). There was a significant association between ozone and asthma ERVs at a 1-day lag (RR 1.179, 95% C.I.: 1.034-1.345). The ambient temperature in cold weather compared with the temperature of minimum asthma ERV showed an RR of 1.214, 95% C.I.: 1.009-1.252 at a 1-day lag. (4) Conclusions: This study provides evidence that short-term exposure to fine suspended particulates, ozone and inverse temperature is associated with asthma exacerbation.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36673790

RESUMO

BACKGROUND: Dementia is a common disease in aging populations. The treatment has mainly focused on memory decline prevention and behavior control. Nonpharmacological treatments, such as cognition training, physical exercise, and music therapy have been effective in slowing memory decline. Chinese calligraphy handwriting (CCH) through breath regulation and fine hand control involves high concentration levels, emotion regulation, and self-awareness. CCH is a mind and body activity that is culturally relevant to older Chinese adults. This study evaluated the beneficial effects of CCH on mild cognitive impairment. METHODS: In 2018, we conducted 8 weeks of CCH training at the Tri-Service General Hospital. The participants were asked to copy a regular script. At the end of the course, they gave oral presentations and showed their work. Self-report questionnaires on emotion, memory, upper limb coordination, attention, and language were collected before and after training. RESULTS: The five questionnaires showed significantly positive feelings after CCH training. The conditions of emotional stability, concentration, hand movement, memory, and speech improved. CONCLUSIONS: CCH training stimulated the brain and improved cognition, psychological symptoms, and hand stability. It is inexpensive and worthwhile for elderly Chinese individuals with mild cognitive impairment to take time daily to practice calligraphy.


Assuntos
Disfunção Cognitiva , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Cognição , Disfunção Cognitiva/terapia , Disfunção Cognitiva/psicologia , Escrita Manual , Transtornos da Memória , Autorrelato , China
14.
Bone ; 168: 116648, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36563716

RESUMO

Osteoporosis induced by disuse because of bed rest or the aerospace industry has become one of the most common skeletal disorders. However, mechanisms underlying the disuse osteoporosis remain largely unknown. We validated the tail-suspended model in mice and demonstrated that there is bone loss in the trabecular and cortical bones of the femur. Importantly, we showed that genetical deletion of hypoxia-inducible factor-1α (HIF-1α) in osteoclasts ameliorated osteoclastic bone resorption in the trabecular bone whereas pharmacological treatment with HIF-1α inhibitor protected the hindlimb-unloaded mice from disuse-induced osteoporosis in the trabecular and cortical bones. The HIF-1α knockout RAW264.7 cells and RNA-sequencing proved that HIF-1α is vital for osteoclastogenesis and bone resorption because it regulated the level of inosine monophosphate dehydrogenase (IMPDH) and cytidine triphosphate synthetase (CTPS) via cellular myelocytomatosis (c-Myc) oncogene. The IMPDH and CTPS are vital nucleotide metabolic enzymes which have an important functional role in cell metabolism, and they can assemble into intracellular linear or ring-shaped structures to cope with cell stress. Interestingly, both in vitro and in vivo, the IMPDH and CTPS cytoophidia were found in osteoclasts, and the level of HIF-1α correlated with osteoclastogenesis and bone-resorbing activity. Our data revealed that HIF-1α/c-Myc/cytoophidia signalling might be required for osteoclasts to mediate cell metabolism in disuse-induced osteoporosis. Overall, our results revealed a new role of HIF-1α/c-Myc/cytoophidia in supporting osteoclastogenesis and bone resorption and exposed evidence for its role in the pathogenesis of disuse osteoporosis, which might provide promising therapeutic targets.


Assuntos
Reabsorção Óssea , Subunidade alfa do Fator 1 Induzível por Hipóxia , Osteoporose , Animais , Camundongos , Reabsorção Óssea/patologia , Fêmur/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Osteoclastos/metabolismo , Osteoporose/patologia
15.
Micromachines (Basel) ; 13(10)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36295921

RESUMO

Conventional photovoltaic (PV) grid-connected systems consist of a boost converter cascaded with an inverter, resulting in poor efficiency due to performing energy processing twice. Many pseudo DC-link inverters with single energy processing have been proposed to improve system efficiency and simplify circuits. However, their output voltage gain is limited by the non-ideal characteristics of the power diode, making them difficult to apply in high-output voltage applications. This paper proposes combining a boost converter with magnetic coupling and a full-bridge unfolding circuit to develop an inverter featuring high voltage-gain and high efficiency. According to the desired instantaneous output voltage, the high-gain boost converter and the full-bridge unfolding circuit are sequentially and respectively controlled by SPWM. A sinusoidal output voltage can be generated by performing energy processing only once, effectively improving the conversion efficiency. Magnetic coupling is adopted to increase the voltage gain of step-up, and the step-down function is realized by the full-bridge unfolding circuit to reduce conduction loss. Finally, a 500 W prototype was fabricated for the proposed high-gain inverter. The experimental results were used to verify the correctness of the theoretical analysis and the feasibility of the circuit structure.

16.
Micromachines (Basel) ; 13(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36296075

RESUMO

True sine wave DC-to-AC inverters are becoming more and more important in solar power generation in order to raise the system's efficiency. A high-quality true sine wave DC-to-AC inverter can be built with a robust intelligent control method. This robust intelligent control method is comprised of improved sliding mode reaching law (ISMRL) and particle swarm optimization (PSO)-catfish effect (CE). The sliding mode reaching law is robust and insensitive to parameter variations and external disturbances. However, it has infinite system-state convergence times and steady-state errors. In addition, solar panels are often affected by partial shading, causing the output power-voltage characteristic curve to be multi-peaked. Such a situation causes misjudgment of the maximum power point tracking with conventional algorithms, which can neither obtain the global extremes nor establish high conversion efficiency. Therefore, this paper proposes an ISMRL based on PSO-CE applied to the tracking of maximum power in the case of partial shading of a solar power generation system. The ISMRL guarantees quick terminable time convergence, making it well-suited for digital implementation. In this paper, PSO-CE is used to find the global best solution of ISMRL, rejecting steady-state errors, slow convergence, and premature trapping in local optimums. Simulation and experimental results are verified using digital implementation based on a Texas Instruments digital signal processor to produce more accurate and better tracking control of true sine wave DC-to-AC inverter-based solar power generation systems.

17.
Front Genet ; 13: 909095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35801079

RESUMO

Background: Osteoclasts, which are multinucleated cells formed by monocyte fusion, play a key role in bone resorption. Hypoxia-inducible factor (HIF)-1α is vital for the development of osteoclasts in hypoxic environments and during bone resorption. However, additional research is required to further study the HIF-1α-dependent regulation of osteoclast differentiation at the genetic level. Methods: In our study, RNA sequencing (RNA-seq) was used to identify the expression profiles of long noncoding RNAs (lncRNAs) and mRNAs in conditional HIF-1α-knockout osteoclasts. Results: A total of 1,320 mRNAs and 95 lncRNAs were differentially expressed. The expression of lncRNAs MSTRG.7566.12 and MSTRG.31769.2 were strongly negatively correlated with that of Mmp9, Ctsk, etc. Conclusion: Our research provides a basis for further understanding the role of mRNAs and lncRNAs in conditional HIF-1α-knockout osteoclasts, and many of these molecules may be potential targets for treating bone diseases related to HIF-1α.

18.
Life (Basel) ; 12(6)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35743808

RESUMO

Background: Premenstrual syndrome (PMS) is a multifactorial disorder caused by hormone and autonomic imbalance. In our study, hyperglycemia-induced insulin secretion increased progesterone secretion and progressive autonomic imbalance. The young patients with diabetes mellitus (DM) revealed hypo-parasympathetic function and hypersympathetic function compared with nondiabetic controls. Young female patients with DM with higher blood sugar and autonomic malfunction may be associated with PMS. However, there is a lack of evidence about DM in females related to PMS. We evaluated female patients with DM who subsequently followed PMS in a retrospective cohort study. Methods: We retrieved data from the National Health Insurance Research Database in Taiwan. Female patients with DM between 20 and 50 years old were assessed by the International Classification of Disease, 9 Revision, Clinical Modification (ICD-9-CM) disease code of 250. Patients who were DM-free females were fourfold matched to the control group by age and disease index date. The ICD-9-CM disease code of 625.4 identified the incidence of PMS followed by the index date as events. The possible risk factors associated with PMS were detected with a Cox proportional regression. Results: DM was a significant risk factor for PMS incidence with an adjusted hazard ratio of 1.683 (95% confidence interval: 1.104−2.124, p < 0.001) in females after adjusting for age, other comorbidities, season, urbanization status of patients and the hospital status of visiting. Conclusions: This study noted an association between DM and PMS in female patients. Healthcare providers and female patients with DM must be aware of possible complications of PMS, aggressive glycemic control, decreased hyperglycemia and autonomic dysfunction to prevent this bothersome disorder.

19.
Medicina (Kaunas) ; 58(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35744016

RESUMO

Background and Objectives: Sepsis increases cardiovascular disease and causes death. Ischemic heart disease (IHD) without acute myocardial infarction has been discussed less, and the relationship between risk factors and IHD in septicemia survivors within six months is worthy of in-depth study. Our study demonstrated the incidence of IHD and the possible risk factors for IHD in septicemia patients within six months. Materials and Methods: An inpatient dataset of the Taiwanese Longitudinal Health Insurance Database between 2001 and 2003 was used. The events were defined as rehospitalization of stroke and IHD after discharge or death within six months after the first septicemia hospitalization. The relative factors of major adverse cardiovascular events (MACEs) and IHD were identified by multivariate Cox proportional regression. Results: There were 4323 septicemia survivors and 404 (9.3%) IHD. New-onset atrial fibrillation had a hazard ratio (HR) of 1.705 (95% confidence interval (C.I.): 1.156-2.516) for MACEs and carried a 184% risk with HR 2.836 (95% C.I.: 1.725-4.665) for IHD by adjusted area and other risk factors. Conclusions: This study explored advanced-aged patients who experienced more severe septicemia with new-onset atrial fibrillation, which increases the incidence of IHD in MACEs within six months of septicemia. Therefore, healthcare providers must identify patients with a higher IHD risk and modify risk factors beforehand.


Assuntos
Fibrilação Atrial , Isquemia Miocárdica , Sepse , Idoso , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Humanos , Isquemia Miocárdica/complicações , Isquemia Miocárdica/epidemiologia , Alta do Paciente , Fatores de Risco , Sepse/complicações , Sepse/epidemiologia
20.
Micromachines (Basel) ; 13(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35630264

RESUMO

A novel interleaved DC-DC buck converter is proposed to drive high-brightness light-emitting diodes (LEDs). The circuit configuration mainly consists of two buck converters, which are connected in parallel and use interleaved operation. Through interleaved operation, the power capability of the converter is doubled. Traditionally, two individual inductors are used in the two buck converters. The difference between conventional parallel-operated buck converters using two energy storage inductors and the proposed circuit is that the proposed circuit uses two small inductors and a coupled inductor that replace the two inductors of the buck converters. In this way, both buck converters can be designed to operate in discontinuous-current mode (DCM), even if the magnetizing inductance of the coupled inductor is large. Therefore, the freewheeling diodes can achieve zero-current switching off (ZCS). Applying the principle of conservation of magnetic flux, the magnetizing current is converted between the two windings of the coupled inductor. Because nearly constant magnetizing current continuously flows into the output, the output voltage ripple can be effectively reduced without the use of large-value electrolytic capacitors. In addition, each winding current can drop from positive to negative, and this reverse current can discharge the parasitic capacitor of the active switch to zero volts. In this way, the active switches can operate at zero-voltage switching on (ZVS), leading to low switching losses. A 180 W prototype LED driver was built and tested. Our experimental results show satisfactory performance.

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