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1.
ACS Nano ; 18(28): 18635-18649, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38950148

RESUMEN

Prevailing over the bottleneck of von Neumann computing has been significant attention due to the inevitableness of proceeding through enormous data volumes in current digital technologies. Inspired by the human brain's operational principle, the artificial synapse of neuromorphic computing has been explored as an emerging solution. Especially, the optoelectronic synapse is of growing interest as vision is an essential source of information in which dealing with optical stimuli is vital. Herein, flexible optoelectronic synaptic devices composed of centimeter-scale tellurium dioxide (TeO2) films detecting and exhibiting synaptic characteristics to broadband wavelengths are presented. The TeO2-based flexible devices demonstrate a comprehensive set of emulating basic optoelectronic synaptic characteristics; i.e., excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), conversion of short-term to long-term memory, and learning/forgetting. Furthermore, they feature linear and symmetric conductance synaptic weight updates at various wavelengths, which are applicable to broadband neuromorphic computations. Based on this large set of synaptic attributes, a variety of applications such as logistic functions or deep learning and image recognition as well as learning simulations are demonstrated. This work proposes a significant milestone of wafer-scale metal oxide semiconductor-based artificial synapses solely utilizing their optoelectronic features and mechanical flexibility, which is attractive toward scaled-up neuromorphic architectures.

2.
J Bone Metab ; 31(2): 90-100, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38886967

RESUMEN

BACKGROUND: Osteoporosis prevalence continues to escalate with the growth of the older adult population. In this study, we aimed to investigate the profile of osteoporosis treatment-related research articles published in the past 20 years using bibliometric analysis. METHODS: We analyzed all osteoporosis treatment-related articles published between 2001 and 2020 in the Web of Science (WoS) database using bibliometric methods. In the Title search section in WoS, we searched the documents using "osteoporosis treatment"-related keywords. We used the VOSviewer software to construct the bibliometric maps of keyword co-occurrences. RESULTS: Our search yielded 29,738 publications, 21,556 (72.5%) were original articles and 4,529 (15.2%) were review articles and review articles (4,529). We noticed a steady increase in the publication numbers from 2001 to 2020. The overall scientific publication number in WoS increased 3.5-fold, with the five most productive countries being the USA, China, Germany, the United Kingdom, and Japan. The largest contributor was the University of California system. The most productive journals were Osteoporosis International (1,679, 6.4%), Bone (832, 3.2%), and the Journal of Bone and Mineral Research (727, 2.8%). We observed increasing trends in the appearance of denosumab and teriparatide during the last two decades. In our keyword co-occurrence analysis, we constructed four keyword clusters using VOSviewer. CONCLUSIONS: In this study, we provided a gross overview of the visibility and productivity of research studies in osteoporosis treatment. Substantial changes have occurred in osteoporosis treatment over the last 20 years. The effector mechanism of anti-osteoporosis medications could be future hot spots in osteoporosis research. We believe that our study is a valuable guide for clinicians related to the global outputs of osteoporosis treatment.

3.
ACS Appl Mater Interfaces ; 16(15): 19057-19067, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38564293

RESUMEN

Preventing ferroelectric materials from losing their ferroelectricity over a low thickness of several nanometers is crucial in developing multifunctional nanoelectronics. Epitaxially grown 5 at. % yttrium-doped Hf0.5Zr0.5O2 (YHZO) thin films exhibit an atomically smooth surface, an ability to maintain ferroelectricity even at a thickness of 10 nm, and excellent insulating properties, making them suitable for use as gate oxides in ferroelectric thin film transistors (FeTFTs). Through the epitaxial growth of a YHZO/La0.67Sr0.33MnO3 (LSMO)/SrTiO3 (STO) heterostructure, YHZO effectively retains its ferroelectricity and orthorhombic single phase, leading to enhancing electron mobility (∼19.74 cm2 V-1 s-1) and memory window (3.7 V) in the amorphous InGaZnO4 (a-IGZO)/YHZO/LSMO/STO FeTFTs. These FeTFTs demonstrate a consistent memory function with remarkable endurance (∼106 cycles) and retention (∼104 s). Furthermore, they sustain a constant memory window even under ±6 V bias stress for 104 s and exhibit excellent stability even under ±6 V/1 ms pulse cycling for 107 cycles. For comparison, a transistor with the same structure was fabricated using epitaxial nonferroelectric LaAlO3 (LAO) and epitaxial undoped Hf0.5Zr0.5O2 (HZO) as alternatives to YHZO. This study presents a novel approach to exploit the potential of YHZO in FeTFTs, contributing to the development of next-generation logic-in-memory.

4.
ACS Appl Mater Interfaces ; 16(13): 16453-16461, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38516695

RESUMEN

Memristors integrated into a crossbar-array architecture (CAA) are promising candidates for analog in-memory computing accelerators. However, the relatively low reliability of the memristor device and sneak current issues in CAA remain the main obstacles. Alkali ion-based interface-type memristors are promising solutions for implementing highly reliable memristor devices and neuromorphic hardware. This interface-type device benefits from self-rectifying and forming-free resistive switching (RS), and exhibits relatively low variation from device to device and cycle to cycle. In a previous report, we introduced an in situ grown Na/TiO2 memristor using atomic layer deposition (ALD) and proposed a RS mechanism from experimentally measured Schottky barrier modulation. Self-rectifying RS characteristics were observed by the asymmetric distribution of Na dopants and oxygen vacancies as the Ti metal used as the adhesion layer for the bottom electrode diffuses over the Pt electrode at 250 °C during the ALD process and is doped into the TiO2 layer. Here, we theoretically verify the modulation of the Schottky barrier at the TiO2/Pt electrode interface by Na ions. This study fabricated a Pt/Na/TiO2/Pt memristor device and confirmed its self-rectifying RS characteristics and stable retention characteristics for 24 h at 85 °C. Additionally, this device exhibited relative standard deviations of 27 and 7% in the high and low resistance states, respectively, in terms of cycle-to-cycle variation. To verify the RS mechanism, we conducted density functional theory simulations to analyze the impact of Na cations at interstitial sites on the Schottky barrier. Our findings can contribute to both fundamental understanding and the design of high-performance memristor devices for neuromorphic computing.

5.
ACS Nano ; 18(8): 6373-6386, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38349619

RESUMEN

Ionic memristor devices are crucial for efficient artificial neural network computations in neuromorphic hardware. They excel in multi-bit implementation but face challenges like device reliability and sneak currents in crossbar array architecture (CAA). Interface-type ionic memristors offer low variation, self-rectification, and no forming process, making them suitable for CAA. However, they suffer from slow weight updates and poor retention and endurance. To address these issues, the study demonstrated an alkali ion self-rectifying memristor with an alkali metal reservoir formed by a bottom electrode design. By adopting Li metal as the adhesion layer of the bottom electrode, an alkali ion reservoir was formed at the bottom of the memristor layer by diffusion occurring during the atomic layer deposition process for the Na:TiO2 memristor layer. In addition, Al dopant was used to improve the retention characteristics by suppressing the diffusion of alkali cations. In the memristor device with optimized Al doping, retention characteristics of more than 20 h at 125 °C, endurance characteristics of more than 5.5 × 105, and high linearity/symmetry of weight update characteristics were achieved. In reliability tests on 100 randomly selected devices from a 32 × 32 CAA device, device-to-device and cycle-to-cycle variations showed low variation values within 81% and 8%, respectively.

6.
Adv Mater ; 36(1): e2307334, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37708845

RESUMEN

Numerous efforts for emulating organ systems comprised of multiple functional units have driven substantial advancements in bio-realistic electronics and systems. The resistance change behavior observed in diffusive memristors shares similarities with the potential change in biological neurons. Here, the diffusive threshold switching phenomenon in Ag-incorporated organometallic halide perovskites is utilized to demonstrate the functions of afferent neurons. Halide perovskites-based diffusive memristors show a low threshold voltage of ≈0.2 V with little variation, attributed to the facile migration of Ag ions uniformly dispersed within the halide matrix. Based on the reversible and reliable volatile threshold switching, the memristors successfully demonstrate fundamental nociceptive functions including threshold firing, relaxation, and sensitization. Furthermore, to replicate the biological mechano-nociceptive phenomenon at a system level, an artificial mechano-nociceptive system is built by integrating a diffusive memristor with a force-sensing resistor. The presented system is capable of detecting and discerning the detrimental impact caused by a heavy steel ball, effectively exhibiting the corresponding sensitization response. By further extending the single nociceptive system into a 5 × 5 array, successful stereoscopic nociception of uneven impulses is achieved in the artificial skin system through array-scale sensitization. These results represent significant progress in the field of bio-inspired electronics and systems.

7.
Eur J Clin Invest ; 54(1): e14092, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37725441

RESUMEN

BACKGROUND: Seasonal variation and sunlight exposure can impact serum vitamin D levels, potentially influencing lupus symptoms. We investigated seasonal vitamin D levels and their correlation with clinical manifestations and disease activity in systemic lupus erythematosus (SLE). METHODS: Serum 25(OH) vitamin D3 (25(OH)D3) levels were categorised as deficient (25(OH)D3 < 10 ng/mL), insufficient (10-30 ng/mL) and sufficiency (>30 ng/mL) in participants analysed in winter (n = 407) and summer (n = 377). Logistic regression analysis was performed to assess the impact of vitamin D levels on achieving a lupus low disease activity state (LLDAS), stratified by season. RESULTS: The mean serum 25(OH)D3 levels differed significantly between the winter and summer measurement groups (22.4 vs. 24.2 ng/mL; p = .018). The prevalences of vitamin D deficiency, insufficiency and sufficiency in the winter group were 12.8%, 66.6% and 20.6%, respectively, compared with 4.5%, 67.9% and 27.6% in the summer group. Achieving LLDAS was highest in the vitamin D sufficiency group (winter: 56.6%, summer: 55%) and lowest in the vitamin D deficiency group (winter: 15.4%, summer: 13.6%), with significant differences (all p < .001). Multivariate analysis identified SLE disease activity index ≤4, normal anti-double-stranded DNA and vitamin D sufficiency as significant factors for achieving LLDAS in both seasons. CONCLUSIONS: Sufficient vitamin D levels are important for achieving LLDAS in patients with SLE during winter and summer. Therefore, physicians should pay attention to the adequacy of vitamin D levels and consider recommending vitamin D supplementation for patients with vitamin D insufficiency.


Asunto(s)
Lupus Eritematoso Sistémico , Deficiencia de Vitamina D , Humanos , Vitamina D , Estaciones del Año , Deficiencia de Vitamina D/epidemiología , Lupus Eritematoso Sistémico/epidemiología , Vitaminas
8.
J Orthop Surg (Hong Kong) ; 31(3): 10225536231199392, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37878458

RESUMEN

BACKGROUND: Mycobacterium avium complex (MAC) prosthetic joint infection (PJI) has been rarely reported. METHODS: This study aimed to investigate the epidemiology and outcomes of MAC PJI. A systematic review of the literature regarding the MAC infection following total joint arthroplasty including hip and knee joint was performed. Multiple databases were searched for published English-written articles up to May 2023. Studies that reported cases of PJI by MAC were reviewed. RESULTS: A total of 17 patients were identified and analyzed from 11 published studies. All patients presented with joint symptom of pain or swelling prior to the diagnosis and MAC was confirmed by culture. The most of the patients (16/17 patients, 94.1%) were noted to have underlying medical condition(s) that might have affected immunity. Treatment consisted of anti-MAC medication therapy only in two patients and anti-MAC medication therapy plus surgery in 15 patients. Among the patients who underwent surgery, 14 patients (82.3%) had removal of the prosthesis including seven patients who had two-stage surgery to have reimplantation of the prosthesis. No relapse of MAC infection was reported despite of one case of relapse of infection caused by different pyogenic bacteria. The rate of overall mortality was 29.4%, however, identified attributable mortality due to MAC infection was low (5.9%). CONCLUSION: PJI by MAC is a rare disease. However, MAC needs to be considered in the differential diagnosis in immunocompromised patients presenting with symptoms of PJI. Two-stage exchange arthroplasty may result in successful treatment outcomes without higher risks of relapse of infection if undertaken in association with appropriate active anti-MAC antibiotic therapy.


Asunto(s)
Artritis Infecciosa , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Infección por Mycobacterium avium-intracellulare , Infecciones Relacionadas con Prótesis , Humanos , Complejo Mycobacterium avium , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Cadera/efectos adversos , Infección por Mycobacterium avium-intracellulare/diagnóstico , Infección por Mycobacterium avium-intracellulare/epidemiología , Infección por Mycobacterium avium-intracellulare/terapia , Prótesis e Implantes/efectos adversos , Antibacterianos/uso terapéutico , Artritis Infecciosa/diagnóstico , Artritis Infecciosa/epidemiología , Artritis Infecciosa/terapia , Recurrencia , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/epidemiología , Infecciones Relacionadas con Prótesis/terapia , Estudios Retrospectivos
9.
Indian J Orthop ; 57(6): 818-826, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37214358

RESUMEN

Background: The incidence of injuries associated with the use of electric scooter (e-scooter) has consistently increased since the launch of the first shared e-scooter systems in late 2017. The aim with this review was to investigate the epidemiological characteristics of fractures related to e-scooter accidents. Methods: A systematic review of the all published papers was conducted regarding epidemiologic characteristics of traumatic fractures following e-scooter-related injuries. Multiple databases of PubMed, Web of Science, EMBASE, and Cochrane library were searched and relevant clinical studies reporting incidence for traumatic fractures from e-scooter-related injuries were included. All other types of studies and those including patients with non-orthopedic injuries were excluded. The Methodological Index for Non-randomized Studies (MINORS) was used to assess the quality of the included studies. The characteristics of patients were analyzed by the mean and the standard deviation for continuous variables. Results: Eleven published studies (6579 patients) were identified which have been reported from Nov, 2019 to Sep, 2021. Periods of research in each study were different from May, 2017 to July, 2020. In the majority of cases, the mechanism of injury was a fall from the scooter (84.8%), which was followed by e-scooter motor vehicle accident (7.4%) and collision (5.5%). Regarding the fractures, upper limb injuries were the most prevalent (65%) and radial fracture was the most common fracture type of the upper limb (28.2%). Lower limb fractures were recorded in 475 (25.3%) patients, the most common being tibial fractures (8.4%). Conclusions: As e-scooter market continues to considerably rise, the incidence of major orthopedic traumas is also likely to increase. Despite potential selection and reporting biases, our systematic review suggested up-to-date guidelines for the epidemiology of fractures following e-scooter injury. According to the results found in the present study, we believe that it is reasonable to mandate helmet use and the obligation to wear other types of safety equipment such as elbow and knee pads should be discussed.

10.
Nanomicro Lett ; 15(1): 69, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36943534

RESUMEN

Recently, artificial synapses involving an electrochemical reaction of Li-ion have been attributed to have remarkable synaptic properties. Three-terminal synaptic transistors utilizing Li-ion intercalation exhibits reliable synaptic characteristics by exploiting the advantage of non-distributed weight updates owing to stable ion migrations. However, the three-terminal configurations with large and complex structures impede the crossbar array implementation required for hardware neuromorphic systems. Meanwhile, achieving adequate synaptic performances through effective Li-ion intercalation in vertical two-terminal synaptic devices for array integration remains challenging. Here, two-terminal Au/LixCoO2/Pt artificial synapses are proposed with the potential for practical implementation of hardware neural networks. The Au/LixCoO2/Pt devices demonstrated extraordinary neuromorphic behaviors based on a progressive dearth of Li in LixCoO2 films. The intercalation and deintercalation of Li-ion inside the films are precisely controlled over the weight control spike, resulting in improved weight control functionality. Various types of synaptic plasticity were imitated and assessed in terms of key factors such as nonlinearity, symmetricity, and dynamic range. Notably, the LixCoO2-based neuromorphic system outperformed three-terminal synaptic transistors in simulations of convolutional neural networks and multilayer perceptrons due to the high linearity and low programming error. These impressive performances suggest the vertical two-terminal Au/LixCoO2/Pt artificial synapses as promising candidates for hardware neural networks.

11.
Anesth Pain Med (Seoul) ; 18(1): 70-74, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36746905

RESUMEN

BACKGROUND: Lymphedema is characterized by localized tissue swelling due to excessive interstitial space retention of lymphatic fluid. Lymphedema is easy to be misdiagnosed since itresembles other conditions of extremity swelling. We present a case of complex regionalpain syndrome (CRPS) type I with secondary lymphedema that was successfully managedwith spinal cord stimulation (SCS). CASE: A 39-year-old female patient came to our pain clinic with complaints of lower extremity pain and edema. To find out reason of leg edema, computed tomography of extremity angiography and blood test were performed. However, all of evaluations were normal. Lastlyperformed lymphoscintigraphy showed secondary lymphedema. SCS was performed and itshowed dramatic reduction subsequent to implantation of SCS. CONCLUSIONS: We could successfully manage the intractable pain and edema in CRPS combined with lymphedema. If a patient presents different nature of edema, coexistence of other disease needs to be considered.

12.
Pain Physician ; 26(1): 39-44, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36791292

RESUMEN

BACKGROUND: Trigeminal neuralgia (TN) is usually established using characteristic clinical features such as sudden, severe, and unilateral facial pain. Studies about diverse clinical features and epidemiologic data of TN have been reported previously; however, most of the previous studies have evaluated in and focused on Caucasian and Western populations. OBJECTIVES: The purpose of this study was to evaluate diverse clinical features, currently applied types of treatment, and brain imaging studies in patients with TN in a Korean population. STUDY DESIGN: Retrospective analysis. SETTING: An interventional pain management practice in South Korea. METHODS: Patients with a primary diagnosis of TN were identified using Clinical Data Warehouse v 2.5 (CDW, Planit Healthcare, Seoul, Korea) using the key words "trigeminal neuralgia and G50.0 (International classification of disease 10 code)." RESULTS: TN occurred predominantly between the fifth and seventh decades of life, with female predominance. The V3 division and unilateral right-side involvement were the most common affected region. An electric shock like sensation and the intraoral side (teeth and gingiva) were the most common pain description and location, respectively. Normal brain imaging studies and vascular compression on the trigeminal nerve were observed in 92 (64.7%) and 36 (25%) patients, respectively. The superior cerebellar artery was the most common offending vessel (19;13.3%). Monotherapy with carbamazepine alone was the most common (91;37.7%), whereas radiofrequency thermoablation was the most common invasive treatment. LIMITATIONS: The results of this study were based on data on TN patients from a single center. The generalizability of the findings to the Korean population is thus limited. CONCLUSION: There is little difference between Korean and other Asian patients with TN in their demographic and clinical characteristics.


Asunto(s)
Neuralgia del Trigémino , Humanos , Femenino , Masculino , Neuralgia del Trigémino/terapia , Neuralgia del Trigémino/diagnóstico , Estudios Retrospectivos , Resultado del Tratamiento , Nervio Trigémino , Manejo del Dolor/métodos
13.
J Orthop Surg (Hong Kong) ; 30(3): 10225536221147082, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36541833

RESUMEN

BACKGROUND: Two injectable anti-osteoporosis medications, denosumab and zoledronic acid, have been widely used to treat patients with severe osteoporosis. The purpose of this study was to evaluate the real-world effectiveness and adherence of denosumab compared to zoledronic acid in geriatric patients after a hip fracture. METHODS: A total of 282 patients treated with osteoporotic hip fracture between March 2014 and Aug 2022 were retrospectively reviewed. The patients were asked to select the anti-osteoporosis medication after surgery. Treatment persistence was monitored by follow-up visit to the outpatient clinic at postoperative 2 years. RESULTS: Of 282 individuals with baseline data, 162 patients took subcutaneous denosumab and 120 patients took intravenous zoledronic acid. At postoperative 2 years, the change in bone mineral density (BMD) from baseline was greater in the denosumab group compared with the zoledronic acid group (p < 0.001). The rate of persistence to denosumab was significantly higher than that for 12-months zoledronic acid (p = 0.01). Serious adverse events were similar in the two groups. CONCLUSIONS: Our study revealed the effectiveness and patients' persistence for two commonly used anti-osteoporosis agents after hip fracture. In this frail, elderly population, half-yearly denosumab was superior to yearly zoledronic acid in BMD and demonstrated significant higher persistence rate, indicating a potential therapeutic advantage that warrants further validation.


Asunto(s)
Conservadores de la Densidad Ósea , Fracturas de Cadera , Osteoporosis Posmenopáusica , Osteoporosis , Fracturas Osteoporóticas , Humanos , Anciano , Femenino , Ácido Zoledrónico/uso terapéutico , Denosumab/uso terapéutico , Estudios Retrospectivos , Osteoporosis/complicaciones , Osteoporosis/tratamiento farmacológico , Fracturas Osteoporóticas/tratamiento farmacológico , Fracturas Osteoporóticas/cirugía , Densidad Ósea , Fracturas de Cadera/cirugía , Difosfonatos/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico
14.
Nano Lett ; 22(14): 6010-6017, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35675157

RESUMEN

In resistive switching memories or artificial synaptic devices, halide perovskites have attracted attention for their unusual features such as rapid ion migration, adjustable composition, and facile synthesis. Herein, the environmentally friendly and highly air stable CsCu2I3 perovskite films are used as the active layer in the Au/CsCu2I3/ITO/glass artificial synapses. The device shows variable synaptic plasticities such as long-term and short-term synaptic plasticity, paired-pulse facilitation, and spike-timing-dependent plasticity by combining potentiation and depression along the formation of conductive filaments. The performances of the devices are maintained for 160 days under ambient conditions. Additionally, the accuracy evaluation of the CsCu2I3-based artificial synapses performs exceptionally well with the MNIST and Fashion MNIST data sets, demonstrating high learning accuracy in deep neural networks. Using the novel B-site engineered halide perovskite material with extreme air stability, this study paves the way for artificial synaptic devices for next-generation in-memory hardware.


Asunto(s)
Plasticidad Neuronal , Sinapsis , Redes Neurales de la Computación
15.
Small ; 18(12): e2106613, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35060312

RESUMEN

In the pandemic era, the development of high-performance indoor air quality monitoring sensors has become more critical than ever. NO2 is one of the most toxic gases in daily life, which induces severe respiratory diseases. Thus, the real-time monitoring of low concentrations of NO2 is highly required. Herein, a visible light-driven ultrasensitive and selective chemoresistive NO2 sensor is presented based on sulfur-doped SnO2 nanoparticles. Sulfur-doped SnO2 nanoparticles are synthesized by incorporating l-cysteine as a sulfur doping agent, which also increases the surface area. The cationic and anionic doping of sulfur induces the formation of intermediate states in the band gap, highly contributing to the substantial enhancement of gas sensing performance under visible light illumination. Extraordinary gas sensing performances such as the gas response of 418 to 5 ppm of NO2 and a detection limit of 0.9 ppt are achieved under blue light illumination. Even under red light illumination, sulfur-doped SnO2 nanoparticles exhibit stable gas sensing. The endurance to humidity and long-term stability of the sensor are outstanding, which amplify the capability as an indoor air quality monitoring sensor. Overall, this study suggests an innovative strategy for developing the next generation of electronic noses.


Asunto(s)
Cisteína , Nanopartículas , Luz , Dióxido de Nitrógeno , Azufre , Compuestos de Estaño
16.
Acta Orthop Traumatol Turc ; 55(5): 439-443, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34730532

RESUMEN

OBJECTIVE: The aim of this study was to evaluate whether COVID-19-related period of societal restrictions and nationwide in 2020 were associated with a significant change in types and frequency of traumatic fractures. METHODS: A systematic review of recent literature on epidemiologic characteristics of traumatic fractures during the outbreak of COVID-19 was conducted. Multiple databases of PubMed, EMBASE, Cochrane library, and Web of Science were searched, and articles comparing incidence for traumatic fractures before and after of COVID-19 outbreak were Results: From 8 published studies which had been reported from July 2020 to September 2020, a total of 9305 patients were identified. The study period of each study included varied from January 24 to May 22 in 2020. There was a significant decrease in the total number of trauma cases during lockdown by 3229 cases (pre-lockdown n = 6267 and lockdown n = 3038), amounting to a decrease by a pooled percentage of 51.6% (P = 0.012). The incidence of hand and tibia fractures decreased while the incidence of femoral fracture significantly increased during COVID-19 outbreak (P < 0.001). There was no significant difference in the fracture frequency for all other skeletal areas (P > 0.05). CONCLUSION: Evidence suggests that there was a significant decrease in the overall number of traumatic fractures during the COVID-19-related period of societal restrictions and lockdown. Proportions of most fractured areas were not significantly influenced by the state of emergency, except for femoral fractures, which had occurred more often during this state. Care must be taken, while developing contingency plans for reallocating resources during the COVID-19 pandemic, not to assume that all trauma presentations will decrease. Evidence from this study has suggested there was a significant decrease in the overall number of traumatic fractures during the COVID-19-related period of societal restrictions and lockdown. Proportions of most fractured areas were not significantly influenced by the state of emergency, except for femoral fractures which had occurred more often during this state. LEVEL OF EVIDENCE: Level III, Diagnostic Study.


Asunto(s)
COVID-19 , Fracturas Óseas , Control de Enfermedades Transmisibles , Fracturas Óseas/epidemiología , Humanos , Pandemias , SARS-CoV-2
17.
J Phys Chem Lett ; 12(37): 8999-9010, 2021 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-34515487

RESUMEN

Halide perovskites have been noted for their exotic properties such as fast ion migration, tunable composition, facile synthetic routes, and flexibility in addition to large light absorption coefficients, long carrier diffusion lengths, and high defect tolerance. These properties have made halide perovskites promising materials for memristors. Applications in the field of resistive switching memory devices and artificial synapses for neuromorphic computing are especially noteworthy. This Perspective covers state-of-the-art perovskite-based memristive devices. Moreover, the fundamental mechanisms and characteristics of perovskite-based memristors are elucidated. Interesting opportunities to improve the performance of perovskite-based memristors for commercialization are provided, including improving film uniformity and air stability, controlling the stoichiometry, finding new all-inorganic and lead-free halide perovskites, and making perovskites into single crystals or quantum dots. We expect our Perspective to be the foundation of realizing next-generation halide perovskite-based memristors.

18.
Int J Equity Health ; 20(1): 151, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34465351

RESUMEN

BACKGROUND: In Korea, the universal health system offers coverage to all members of society. Despite this, it is unclear whether risk of death from hepatocellular carcinoma (HCC) varies depending on income. We evaluated the impact of low income on HCC mortality. METHODS: The Korean National Health Insurance sampling cohort was used to identify new HCC cases (n = 7325) diagnosed between 2004 and 2008, and the Korean Community Health Survey data were used to investigate community-level effects. The main outcome was 5-year all-cause mortality risk, and Cox proportional hazard models were applied to investigate the individual- and community-level factors associated with the survival probability of HCC patients. RESULTS: From 2004 to 2008, there were 4658 new HCC cases among males and 2667 new cases among females. The 5-year survival proportion of males was 68%, and the incidence per person-year was 0.768; the female survival proportion was 78%, and the incidence per person-year was 0.819. Lower income was associated with higher hazard ratio (HR), and HCC patients with hepatitis B (HBV), alcoholic liver cirrhosis, and other types of liver cirrhosis had higher HRs than those without these conditions. Subgroup analyses showed that middle-aged men were most vulnerable to the effects of low income on 5-year mortality, and community-level characteristics were associated with survival of HCC patients. CONCLUSION: Having a low income significantly affected the overall 5-year mortality of Korean adults who were newly diagnosed with HCC from 2004 to 2008. Middle-aged men were the most vulnerable. We believe our findings will be useful to healthcare policymakers in Korea as well as to healthcare leaders in countries with NHI programs who need to make important decisions about allocation of limited healthcare resources according to a consensually accepted and rational framework.


Asunto(s)
Carcinoma Hepatocelular , Disparidades en el Estado de Salud , Renta , Neoplasias Hepáticas , Adulto , Anciano , Carcinoma Hepatocelular/mortalidad , Femenino , Humanos , Renta/estadística & datos numéricos , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , República de Corea/epidemiología
19.
Hip Pelvis ; 33(1): 11-17, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33748021

RESUMEN

The nature of implant-related infections is complex. Currently, there is no definitive test for periprosthetic joint infection (PJI) and diagnosis remains challenging despite recent developments. Failure to diagnose and investigate pathologies of the hip appropriately results in delayed management and prolonged patient morbidity. A systematic approach to establishing clear diagnostic criteria for PJI is needed to improve our ability to avoid devastating outcomes associated with these infections. In the current review, we describe an algorithmic approach to the diagnosis of PJI and current controversies surrounding novel diagnostic methods.

20.
iScience ; 24(1): 101889, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33458606

RESUMEN

The expeditious development of information technology has led to the rise of artificial intelligence (AI). However, conventional computing systems are prone to volatility, high power consumption, and even delay between the processor and memory, which is referred to as the von Neumann bottleneck, in implementing AI. To address these issues, memristor-based neuromorphic computing systems inspired by the human brain have been proposed. A memristor can store numerous values by changing its resistance and emulate artificial synapses in brain-inspired computing. Here, we introduce six types of memristors classified according to their operation mechanisms: ionic migration, phase change, spin, ferroelectricity, intercalation, and ionic gating. We review how memristor-based neuromorphic computing can learn, infer, and even create, using various artificial neural networks. Finally, the challenges and perspectives in the competing memristor technology for neuromorphic computing systems are discussed.

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