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This paper provides a comprehensive overview of the security vulnerability known as rowhammer in Dynamic Random-Access Memory (DRAM). While DRAM offers many desirable advantages, including low latency, high density, and cost-effectiveness, rowhammer vulnerability, first identified in 2014, poses a significant threat to computing systems. Rowhammer attacks involve repetitive access to specific DRAM rows, which can cause bit flips in neighboring rows, potentially compromising system credentials, integrity, and availability. The paper discusses the various stages of rowhammer attacks, explores existing attack techniques, and examines defense strategies. It also emphasizes the importance of understanding DRAM organization and the associated security challenges.
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INTRODUCTION: There have been no previous studies comparing serial radiologic results between primary and revision Bankart repair despite the significance of capsulolabral height and slope restoration. The purpose of this study was (1) to compare serially the height and slope of the repaired labrum in the early postoperative period among primary and revision Bankart repair groups, and (2) to compare clinical outcomes between the two groups. MATERIALS AND METHODS: This study included each 24 patients who underwent arthroscopic primary Bankart repair (Group A) and revision Bankart repair (Group B) matched by age, sex, and glenoid defect ratio. Postoperative serial radiologic assessment of the repaired labral height and slope was proceeded using magnetic resonance imaging (MRI) or computed tomographic arthrography (CTA) at 3 weeks and 6 months. RESULTS: There were no significant differences in labral height and slope at 3 weeks and 6 months postoperatively in Group A. However, significant reductions in labral height and slope were evident between 3 weeks and 6 months postoperatively in Group B (P < 0.05). Group A yielded superior results to Group B with respect to labral height and slope at each time point (P < 0.05) in between-group analyses. The clinical outcomes were not significantly different between the two groups except for the patients' return to their premorbid sports activity level (P = 0.024). CONCLUSIONS: The height and slope of the repaired capsulolabral structures in the early postoperative period after arthroscopic revision Bankart repair group were significantly lower than those of the primary Bankart repair group. Also the reduction of labral height and slope was significant in the revision Bankart repair group over time. Nonetheless, clinical outcomes did not differ significantly except return to premorbid sports activity level at final follow-up.
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Inestabilidad de la Articulación , Luxación del Hombro , Articulación del Hombro , Humanos , Articulación del Hombro/cirugía , Articulación del Hombro/diagnóstico por imagen , Análisis por Apareamiento , Inestabilidad de la Articulación/cirugía , Artrografía , Imagen por Resonancia Magnética , Artroscopía/métodos , Luxación del Hombro/cirugía , RecurrenciaRESUMEN
The below-cloud aerosol scavenging process by precipitation is one of the most important mechanisms to remove aerosols from the atmosphere. Due to its complexity and dependence on both aerosol and raindrop sizes, wet scavenging process has been poorly treated, especially during the removal of fine particles. This makes the numerical simulation of below-cloud scavenging in large-scale aerosol models unrealistic. To consider the slip effects of submicron particles, a simplified expression for the diffusion scavenging was developed by approximating the Cunningham slip correction factor. The derived analytic solution was parameterized as a simple power function of rain intensity under the assumption of the lognormal size distribution of particles. The resultant approximated expression was compared to the observed data and the results of previous studies including a 3D atmospheric chemical transport model simulation. Compared with the default GEOS-Chem coefficient of 0.00106R0.61 and the observation-based coefficient of 0.0144R0.9268, the coefficient of a and b in Λm = aRb spread in the range of 0.0002- 0.1959 for a and 0.3261- 0.525 for b over a size distribution of GSD of 1.3-2.5 and a geometric mean diameter of 0.01- 2.5 µm. Overall, this study showed that the scavenging coefficient varies widely by orders of magnitude according to the size distribution of particles and rain intensity. This study also demonstrated that the obtained simplified expression could consider the theoretical approach of aerosol polydispersity. Our proposed analytic approach showed that results can be effectively applied for reduced computational burden in atmospheric modeling.
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Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Simulación por Computador , Modelos Químicos , Aerosoles/análisis , LluviaRESUMEN
BACKGROUND: Sentinel lymph node biopsy (SLNB) is unnecessarily performed too often, owing to the high upstaging rates of ductal carcinoma in situ (DCIS). This study aimed to evaluate the upstaging rates of DCIS to invasive cancer, determine the prevalence of axillary lymph node metastasis, and identify the clinicopathological factors associated with upstaging and lymph node metastasis. We also examined surgical patterns among DCIS patients and determined whether SLNB guidelines were followed. METHODS: We retrospectively analysed 307 consecutive DCIS patients diagnosed by preoperative biopsy in a single centre between 2014 and 2018. Data from clinical records, including imaging studies, axillary and breast surgery types, and pathology results from preoperative and postoperative biopsies, were extracted. Univariate analyses using Chi-square tests and multiple logistic regression analyses were used to analyse the data. RESULTS: The rate of upstaging to invasive cancer was 19.2% (59/307). DCIS diagnosed by core-needle biopsy (odds ratio [OR]: 6.861, 95% confidence interval [CI]: 2.429-19.379), the presence of ultrasonic mass-forming lesions (OR: 2.782, 95% CI: 1.224-6.320), and progesterone receptor-negative status (OR: 3.156, 95% CI: 1.197-8.323) were found to be associated with upstaging. The rate of sentinel lymph node metastasis was only 1.9% (4/202), and all were total mastectomy patients diagnosed by core-needle biopsy. SLNB was performed in 37.2% of 145 breast-conserving surgery patients and 91.4% of 162 total mastectomy patients. Among the 202 patients who underwent SLNB, 145 (71.7%) without invasive cancer on final pathology had redundant SLNB. Two of 59 patients (3.4%) with disease upstaged to invasive cancer had inadequate primary staging of the axilla, as the rate seemed sufficiently small. CONCLUSIONS: In patients with a preoperative diagnosis of DCIS, although an unavoidable possibility of upstaging to invasive cancer exists, axillary metastasis is unlikely. Only 2.7% of patients with DCIS undergoing total mastectomy were found to have sentinel lymph node metastases. SLNB should not be performed in breast-conserving surgery patients and should be reserved only for total mastectomy patients diagnosed by core-needle biopsy.
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Neoplasias de la Mama , Carcinoma Intraductal no Infiltrante , Biopsia del Ganglio Linfático Centinela , Adulto , Axila/patología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Intraductal no Infiltrante/cirugía , Femenino , Humanos , Mastectomía , Persona de Mediana Edad , Estudios Retrospectivos , Procedimientos InnecesariosRESUMEN
For a reliable and stable sensor system, it is essential to precisely measure various sensor signals, such as electromagnetic field, pressure, and temperature. The measured analog signal is converted into digital bits through the sensor readout system. However, in extreme radiation environments, such as in space, during flights, and in nuclear fusion reactors, the performance of the analog-to-digital converter (ADC) constituting the sensor readout system can be degraded due to soft errors caused by radiation effects, leading to system malfunction. This paper proposes a soft-error-tolerant successive-approximation-register (SAR) ADC using dual-capacitor sample-and-hold (S/H) control, which has robust characteristics against total ionizing dose (TID) and single event effects (SEE). The proposed ADC was fabricated using 65-nm CMOS process, and its soft-error-tolerant performance was measured in radiation environments. Additionally, the proposed circuit techniques were verified by utilizing a radiation simulator CAD tool.
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BACKGROUND: Antiplatelet medication has been frequently performed in elderly patients with hip fracture, because of comorbidities. This observational cohort study was to evaluate the effect of continuous perioperative antiplatelet medication on the outcomes after cephalomedullary nailing (CMN) in elderly patients with a proximal femur fracture. METHODS: One hundred and sixty-two consecutive patients aged ≥70 years undergoing CMN for proximal femur fracture between January 2015 and January 2017 were recruited. Of the 162 patients, 47 (study group) taking antiplatelets preoperatively due to comorbidities were compared with 107 (control group) who were not on antiplatelets. 8 patients taking anticoagulant medication were excluded. Postoperative hemoglobin (Hb) and hematocrit (Hct) levels, transfusion amount and estimated blood loss (EBL), occurrence of venous thromboembolism (VTE) and delirium, intensive care unit (ICU) admission, complications, length of hospital stay, readmission, and in-hospital and 1-year mortalities were measured and compared between the two groups. RESULTS: A higher number of patients in the study group had concomitant cardiovascular (p = 0.006) and endocrinologic (p = 0.004) diseases, received perioperative transfusion (p = 0.003), and were admitted to ICU postoperatively (p = 0.014). However, there were no significant differences in postoperative Hb and Hct levels, EBL, length of hospital stay, and the incidences of VTE and delirium between the two groups. In addition, in-hospital and 1-year mortalities as well as postoperative complications showed no significant differences between both groups. CONCLUSIONS: CMN can be performed without delay in elderly patients with proximal femoral fracture receiving antiplatelet therapy prior to admission without discontinuing antiplatelets, and is as safe as in patients who are not on antiplatelet medication. However, more caution is required with respect to transfusions and ICU care after surgery in these patients.
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Fracturas del Fémur/tratamiento farmacológico , Fracturas de Cadera/tratamiento farmacológico , Atención Perioperativa/métodos , Inhibidores de Agregación Plaquetaria/administración & dosificación , Complicaciones Posoperatorias/prevención & control , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Fracturas del Fémur/cirugía , Fracturas de Cadera/cirugía , Humanos , Masculino , Complicaciones Posoperatorias/diagnóstico , Estudios RetrospectivosRESUMEN
For stable and effective control of the sensor system, analog sensor signals such as temperature, pressure, and electromagnetic fields should be accurately measured and converted to digital bits. However, radiation environments, such as space, flight, nuclear power plants, and nuclear fusion reactors, as well as high-reliability applications, such as automotive semiconductor systems, suffer from radiation effects that degrade the performance of the sensor readout system including analog-to-digital converters (ADCs) and cause system malfunctions. This paper investigates an optimal ADC structure in radiation environments and proposes a successive- approximation-register (SAR) ADC using delay-based double feedback flip-flops to enhance the system tolerance against radiation effects, including total ionizing dose (TID) and single event effects (SEE). The proposed flip-flop was fabricated using 130 nm complementary metal-oxide-semiconductor (CMOS) silicon-on-insulator (SOI) process, and its radiation tolerance was measured in actual radiation test facilities. Also, the proposed radiation-hardened SAR ADC with delay-based dual feedback flip-flops was designed and verified by utilizing compact transistor models, which reflect radiation effects to CMOS parameters, and radiation simulator computer aided design (CAD) tools.
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The sweet-tasting protein brazzein is a candidate sugar substitute owing to its sweet, sugar-like taste and good stability. To commercialize brazzein as a sweetener, optimization of fermentation and purification procedure is necessary. Here, we report the expression conditions of brazzein in the yeast Kluyveromices lactis and purification method for maximum yield. Transformed K. lactis was cultured in YPGlu (pH 7.0) at 25 °C and induced by adding glucose:galactose at a weight ratio of 1:2 (%/%) during the stationary phase, which increased brazzein expression 2.5 fold compared to the previous conditions. Cultures were subjected to heat treatment at 80 °C for 1 h, and brazzein containing supernatant was purified using carboxymethyl-sepharose cation exchange chromatography using 50 mM NaCl in 50 mM sodium acetate buffer (pH 4.0) as a wash buffer and 400 mM NaCl (pH 7.0) for elution. The yield of purified brazzein under these conditions was 2.0-fold higher than that from previous purification methods. We also determined that the NanoOrange assay was a suitable method for quantifying tryptophan-deficient brazzein. Thus, it is possible to obtain pure recombinant brazzein with high yield in K. lactis using our optimized expression, purification, and quantification protocols, which has potential applications in the food industry.
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Clonación Molecular/métodos , Microbiología Industrial/métodos , Kluyveromyces/genética , Proteínas de Plantas/genética , Edulcorantes/metabolismo , Vectores Genéticos/genética , Humanos , Kluyveromyces/metabolismo , Proteínas de Plantas/análisis , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/análisis , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Edulcorantes/análisis , Gusto , Triptófano/análisis , Triptófano/genética , Triptófano/metabolismoRESUMEN
BACKGROUND: This study aims to determine the relationship between expression levels of ALDH2 and SOD2 genes and clinical parameters such as alcohol drinking, tobacco smoking, primary site of HNSCC, and human papilloma virus (HPV) state. METHODS: Gene expression data were obtained from gene expression omnibus (GEO accession number: GSE65858). Clinical data (N = 270) including survival result, gender, age, TNM stage, primary site of HNSCC, HPV status, alcohol drinking, and tobacco smoking habit were analyzed according to gene expression pattern. RESULTS: ALDH2 gene was expressed in low levels in patients with heavy alcohol consumption. It was expressed in high (p = 0.01) levels in patients with no or light alcohol consumption. ALDH2 gene was also expressed in low levels in patients with oral cavity cancers or hypopharynx cancers. However, ALDH2 gene was expressed in high (p = 0.03) levels in patients with oropharyngeal cancers or laryngeal cancers. HPV-positive patients were found to have high (p = 0.02) expression levels of ALDH2. SOD2 gene was expressed in high (p = 0.005) levels in patients who had greater mean pack-year of tobacco smoking. Based on log rank test, the group of patients with high expression of ALDH2 showed better (p = 0.002) clinical results than those with low expression of ALDH2. Difference of survival results between ALDH2 high-expressed group and ALDH2 low-expressed group was validated in another cohort (GSE39368, N = 138). CONCLUSIONS: Heavy alcohol drinking downregulates ALDH2 gene expression level. Heavy smoking up-regulates SOD2 gene expression level in patients with head and neck squamous cell carcinoma. The group of patients with low expression levels of ALDH2 showed significantly poorer survival results compared to those with high expression levels of ALDH2.
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Consumo de Bebidas Alcohólicas/patología , Aldehído Deshidrogenasa Mitocondrial/metabolismo , Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Superóxido Dismutasa/metabolismo , Fumar Tabaco/patología , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/virología , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica/métodos , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/virología , Humanos , Masculino , Análisis por Micromatrices/métodos , Persona de Mediana Edad , Papillomaviridae/aislamiento & purificación , Pronóstico , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Análisis de Supervivencia , Regulación hacia ArribaRESUMEN
Agarase catalyzes the hydrolysis of agar, which is primarily used as a medium for microbiology, various food additives, and new biomass materials. In this study, we described the expression of the synthetic gene encoding ß-agarase from Agarivorans albus (Aaß-agarase) in Escherichia coli. The synthetic ß-agarase gene was designed based on the biased codons of E. coli to optimize its expression and extracellular secretion in an active, soluble form. The synthesized agarase gene, including its signal sequence, was cloned into the pET-26 expression vector, and the pET-Aaß-agarase plasmid was introduced into E. coli BL21-Star (DE3) cells. The E. coli transformants were cultured for high-yield secretion of recombinant Aaß-agarase in Luria-Bertani broth containing 0.6 mM isopropyl ß-D-1-thiogalactopyranoside for 9 h at 37°C. The expressed recombinant Aaß-agarase was purified by ammonium sulfate precipitation and diethylaminoethyl-sepharose column chromatography, yielding â¼10 mg/L Aaß-agarase. The purified recombinant Aaß-agarase exhibited optimal activity at pH 7 and 40°C, and its activity was strongly inhibited by Cu2+, Mn2+, Zn2+, and Al3+ ions. Furthermore, the KM and kcat values for purified Aaß-agarase were â¼0.02 mM and â¼45/s, respectively. These kinetic values were up to approximately 15-100-fold lower than the KM values reported for other agarases and approximately 7-30-fold higher than the kcat/KM values reported for other agarases, indicating that recombinant Aaß-agarase exhibited good substrate-binding ability and high catalytic efficiency. These results demonstrated that the E. coli expression system was capable of producing recombinant Aaß-agarase in an active form, at a high yield, and with attributes useful in the relevant industries.
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Alteromonadaceae/enzimología , Alteromonadaceae/genética , Escherichia coli/genética , Glicósido Hidrolasas/genética , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Vectores Genéticos/genética , Glicósido Hidrolasas/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Temperatura , Transformación GenéticaRESUMEN
This paper proposes an envelope-detector-less (EDL) amplitude-shift-keying (ASK) forward telemetry (FT) demodulator for wireless power/data transfer (WPDT) systems. The EDL ASK FT demodulator can substitute bulky and power-hungry components, which are an envelope detector and an analog comparator in the conventional ASK FT demodulator, with a digital controller, reducing both power dissipation and chip area. The proposed demodulator shares the gate control signals of pass transistors, which are used in an ac-dc regulator for wireless power reception, to maintain a constant load voltage while efficiently demodulating the forward telemetry data. Also, a proposed digital cleaner in the EDL demodulator refines this control signal into a wide pulse without suffering from resonant frequency noise, while a synchronizer can align its frequency with the data rate and resonant frequency. The 0.25-µm CMOS prototype chip of the proposed power-path-less EDL ASK FT demodulator, equipped with the ac-dc regulator, demonstrates a significant 38.2% reduction in power dissipation compared to the conventional ASK FT demodulator. Moreover, the EDL ASK FT demodulator occupies only 0.023-mm2 silicon area and achieves a low bit error rate (BER) less than 10-4 while maintaining a regulated voltage of 4.5 V on the load.
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[This corrects the article DOI: 10.3389/fnana.2024.1385932.].
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Transmembrane proteins known as hyperpolarization-activated cyclic nucleotide-gated (HCN) channels control the movement of Na+ and K+ ions across cellular membranes. HCN channels are known to be involved in crucial physiological functions in regulating neuronal excitability and rhythmicity, and pacemaker activity in the heart. Although HCN channels have been relatively well investigated in the brain, their distribution and function in the retina have received less attention, remaining their physiological roles to be comprehensively understood. Also, because recent studies reported HCN channels have been somewhat linked with the dysfunction of photoreceptors which are affected by retinal diseases, investigating HCN channels in the retina may offer valuable insights into disease mechanisms and potentially contribute to identifying novel therapeutic targets for retinal degenerative disorders. This paper endeavors to summarize the existing literature on the distribution and function of HCN channels reported in the vertebrate retinas of various species and discuss the potential implications for the treatment of retinal diseases. Then, we recapitulate current knowledge regarding the function and regulation of HCN channels, as well as their relevance to various neurological disorders.
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Seoul has high PM2.5 concentrations and has not attained the national annual average standard so far. To understand the reasons, we analyzed long-term (2015-2021) hourly observations of aerosols (PM2.5, NO3-, NH4+, SO42-, OC, and EC) and gases (CO, NO2, and SO2) from Seoul and Baekryeong Island, a background site in the upwind region of Seoul. We applied the weather normalization method for meteorological conditions and a 3-dimensional chemical transport model, GEOS-Chem, to identify the effect of policy implementation and aerosol formation mechanisms. The monthly mean PM2.5 ranges between about 20 µg m-3 (warm season) and about 40 µg m-3 (cold season) at both sites, but the annual decreasing rates were larger at Seoul than at Baengnyeong (-0.7 µg m-3 a-1 vs. -1.8 µg m-3 a-1) demonstrating the effectiveness of the local air quality policies including the Special Act on Air Quality in the Seoul Metropolitan Area (SAAQ-SMA) and the seasonal control measures. The weather-normalized monthly mean data shows the highest PM2.5 concentration in March and the lowest concentration in August throughout the 7 years with NO3- accounting for about 40 % of the difference between the two months at both sites. Taking together with the GEOS-Chem model results, which reproduced the elevated NO3- in March, we concluded the elevated atmospheric oxidant level increases in HNO3 (which is not available from the observation) and the still low temperatures in March promote rapid production of NO3-. We used Ox (≡ O3 + NO2) from the observation and OH from the GEOS-Chem as a proxy for the atmospheric oxidant level which can be a source of uncertainty. Thus, direct observations of OH and HNO3 are needed to provide convincing evidence. This study shows that reducing HNO3 levels through atmospheric oxidant level control in the cold season can be effective in PM2.5 mitigation in Seoul.
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This research examines the low rate of co-administration of influenza and COVID-19 vaccines among seniors aged 65 and older in Korea, despite recommendations from authorities and academia worldwide. The study aimed to understand the influence of general characteristics and health beliefs on the vaccination choices of seniors, who were categorized into four groups based on their vaccination status: influenza only, COVID-19 only, both, or neither. A total of 400 participants, aged 65 and above, were selected through proportional stratified random sampling from five major Korean regions for a survey conducted between November 24th and December 15th, 2023. The results indicated no significant differences in general characteristics across these groups. However, regarding the health beliefs showed significant differences in perceived susceptibility and self-efficacy between the influenza-only and co-administration groups. Higher levels of perceived susceptibility and self-efficacy were associated with choosing co-administration. Contrary to previous studies focusing on safety concerns as a primary factor in vaccine hesitancy, this study highlights the role of individual health-related beliefs, particularly perceived susceptibility and self-efficacy, as critical in influencing the decision for co-administration among the elderly in Korea.
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Vacunas contra la COVID-19 , COVID-19 , Vacunas contra la Influenza , Gripe Humana , Humanos , Anciano , Vacunas contra la Influenza/administración & dosificación , Masculino , Femenino , Gripe Humana/prevención & control , República de Corea , Vacunas contra la COVID-19/administración & dosificación , COVID-19/prevención & control , Anciano de 80 o más Años , Vacunación/psicología , Vacunación/estadística & datos numéricos , Vacilación a la Vacunación/estadística & datos numéricos , Vacilación a la Vacunación/psicología , Conocimientos, Actitudes y Práctica en Salud , Encuestas y Cuestionarios , Autoeficacia , SARS-CoV-2/inmunología , Toma de DecisionesRESUMEN
Ulaanbaatar (UB), the fast-growing capital of Mongolia, is known for its world's worst level of particulate matter (PM) concentrations in winter. However, current anthropogenic emission inventories over the UB are based on data from more than fifteen years ago, and satellite observations are scarce because UB is in high latitudes. During the winter of 2020-21, the first period of the Fine Particle Research Initiative in East Asia considering the National Differences (FRIEND), several times higher concentrations of PM in UB compared to other urban sites in East Asia were observed but not reproduced with a chemical transport model mainly due to the underestimated anthropogenic emissions. Therefore, we devised a method for sequentially adjusting emissions based on the reactivity of PM precursors using ground observations. We scaled emission rates for the inert species (CO, elemental carbon (EC), and organic carbon (OC)) to reproduce their observed ambient concentrations, followed by SO2 to reproduce the concentration of SO42-, which was examined to have the least uncertainty based on the abundance of observed NH3, and finally NO and NH3 for NO3-, and NH4+. This improved estimation is compared to regional inventories for Asia and suggests more than an order of magnitude increase in anthropogenic emissions in UB. Using the improved emission inventory, we were able to successfully reproduce independent observation data on PM2.5 concentrations in UB in December 2021 from the U.S. Embassy. During the campaign period, we found more than 50% of the SO42-, NO3-, and NH4+ increased in UB due to the improvement could travel to Beijing, China (BJ), and about 20% of the SO42- could travel to Noto, Japan (NT), more than 3000 km away. Also, the anthropogenic emissions in UB can effectively increase OC, NO3-, and NH4+ concentrations in BJ when Gobi dust storms occur.
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Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Material Particulado , Estaciones del Año , Contaminantes Atmosféricos/análisis , Mongolia , Material Particulado/análisis , Monitoreo del Ambiente/métodos , Contaminación del Aire/estadística & datos numéricos , Efectos AntropogénicosRESUMEN
We present the fabrication of 4 K-scale electrochemical random-access memory (ECRAM) cross-point arrays for analog neural network training accelerator and an electrical characteristic of an 8 × 8 ECRAM array with a 100% yield, showing excellent switching characteristics, low cycle-to-cycle, and device-to-device variations. Leveraging the advances of the ECRAM array, we showcase its efficacy in neural network training using the Tiki-Taka version 2 algorithm (TTv2) tailored for non-ideal analog memory devices. Through an experimental study using ECRAM devices, we investigate the influence of retention characteristics on the training performance of TTv2, revealing that the relative location of the retention convergence point critically determines the available weight range and, consequently, affects the training accuracy. We propose a retention-aware zero-shifting technique designed to optimize neural network training performance, particularly in scenarios involving cross-point devices with limited retention times. This technique ensures robust and efficient analog neural network training despite the practical constraints posed by analog cross-point devices.
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BACKGROUND: Although the 1,927-nm thulium fiber fractional laser is effective and safe for treating photoaging, clinical data regarding this modality remain limited. OBJECTIVE: To investigate the efficacy and safety of the 1,927-nm thulium fiber fractional laser for treating photoaging and melasma in Asians. METHODS: Twenty-five participants received three laser treatments (at 3-week intervals) on the half of the face with more-severe photoaging and melasma. Independent investigators evaluated clinical improvement 2 and 6 months after the final treatment. Improvement in melasma was evaluated using the Melasma Area and Severity Index. Subjective satisfaction rates were also evaluated. Adverse events were assessed, and pain was scored using a visual analog scale (VAS). Histologic changes were observed using immunohistochemical staining. RESULTS: Clinical improvement of photodamaged facial skin was remarkable on the treatment side. Most participants reported that their subjective satisfaction rate was greater than slight satisfaction. Downtime for healing required approximately 1 week. No severe adverse events occurred. Mean VAS score during treatment was 4.8. Collagen regeneration and melanin decrease were observed histologically. CONCLUSION: The 1,927-nm thulium fiber fractional laser is a safe, effective treatment for photoaging and melasma in Asians.
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Rayos Láser , Melanosis/cirugía , Envejecimiento de la Piel , Tulio , Adulto , Pueblo Asiatico , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Método Simple CiegoRESUMEN
A power-efficient wireless stimulating system for a head-mounted deep brain stimulator (DBS) is presented. A new adaptive rectifier generates a variable DC supply voltage from a constant AC power carrier utilizing phase control feedback, while achieving high AC-DC power conversion efficiency (PCE) through active synchronous switching. A current-controlled stimulator adopts closed-loop supply control to automatically adjust the stimulation compliance voltage by detecting stimulation site potentials through a voltage readout channel, and improve the stimulation efficiency. The stimulator also utilizes closed-loop active charge balancing to maintain the residual charge at each site within a safe limit, while receiving the stimulation parameters wirelessly from the amplitude-shift-keyed power carrier. A 4-ch wireless stimulating system prototype was fabricated in a 0.5-µm 3M2P standard CMOS process, occupying 2.25 mm². With 5 V peak AC input at 2 MHz, the adaptive rectifier provides an adjustable DC output between 2.5 V and 4.6 V at 2.8 mA loading, resulting in measured PCE of 72 ~ 87%. The adaptive supply control increases the stimulation efficiency up to 30% higher than a fixed supply voltage to 58 ~ 68%. The prototype wireless stimulating system was verified in vitro.
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ETHNOPHARMACOLOGICAL RELEVANCE: Echinosophora koreensis Nakai is an endemic plant species distributed in a limited area within the Korean province of Gangwon, including the Yanggu-gun, Inje-gun, Cheorwon-gun, Chuncheon-si, and Hongcheon-gun counties. It is used in traditional medicine to treat various disorders, such as fever, skin diseases, diuresis, and neuralgia. MATERIALS AND METHODS: This study demonstrated the effects of E. koreensis Nakai root extract (EKRE) on lipopolysaccharide (LPS)-induced inflammatory responses in vitro and in vivo. Cell viability was assessed through a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Nitric oxide (NO) production was measured using Griess reagent. Interleukin (IL)-6 and tumor necrosis factor (TNF) levels were assessed using enzyme-linked immunosorbent assays. Inducible nitric oxide synthase (iNOS), nuclear factor kappa-B (NF-κB), and mitogen-activated protein kinase (MAPK) expression were assessed using Western blot analysis. To examine the effects of EKRE in vivo, it was administered orally at doses of 50 or 200 mg/kg for 3 days in mice. Edema in the paws was induced through λ-carrageenan injection and measured hourly for up to 5 h using calipers. RESULTS: EKRE markedly suppressed LPS-generated NO, IL-6, and iNOS production in RAW 264.7 cells. Moreover, it suppressed the activation of the NF-κB and MAPK in LPS-stimulated cells. Furthermore, EKRE significantly inhibited carrageenan-induced edema in mouse paws. There were no significant differences in IL-6 and TNF production in paw tissue harvested from mice, but levels decreased at high EKRE concentrations (200 mg/kg). CONCLUSION: The results of this study provided validation for EKRE-induced inhibition of inflammatory responses in vitro and in vivo. This research suggested that EKRE is a promising treatment for inflammatory disorders.