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1.
Nano Lett ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39316704

RESUMO

The excessive power consumption is challenging for phase change memory (PCM) on its way to becoming universal memory in complex hierarchies of memory systems. Here, from the perspective of device structure, by adding a nanocurrent-channel (NCC) layer between the electrode layer and phase change layer, a RESET power consumption reduction by more than 95% and 10 times faster SET speed were realized simultaneously. Through the first principle calculations, Au and SiO2 were screened as the metal and insulating matrix material of NCC layer, respectively. Our PCM device with a Au-SiO2 NCC layer shows an ultralow RESET power consumption, down to 381 fJ, and an ultrafast SET speed (8 ns). Much higher current density near NCC in the phase change layer and thermal barrier effect of insulating matrix material were confirmed by finite element analysis (FEA), and the role of Au nanochannels was revealed by transmission electron microscopy (TEM). Our NCC layer structure provides a simple and practicable method to significantly decrease PCM power consumption.

2.
Nano Lett ; 24(1): 9-15, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38115185

RESUMO

The universality of physical phenomena is a pivotal concept underlying quantum standards. In this context, the realization of a quantum current standard using silicon single-electron pumps necessitates the verification of the equivalence across multiple devices. Herein, we experimentally investigate the universality of pumped currents from two different silicon single-electron devices which are placed inside the cryogen-free dilution refrigerator whose temperature (mixing chamber plate) was ∼150 mK under the operation of the pump devices. By direct comparison using an ultrastable current amplifier as a galvanometer, we confirm that two pumped currents are consistent with ∼1 ppm uncertainty. Furthermore, we realize quantum-current multiplication with a similar uncertainty by adding the currents of two different gigahertz (GHz)-operated silicon pumps, whose generated currents are confirmed to be identical. These results pave the way for realizing a quantum current standard in the nanoampere range and a quantum metrology triangle experiment using silicon pump devices.

3.
Nano Lett ; 24(37): 11403-11410, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39083658

RESUMO

The high operating voltage of conventional nanoelectromechanical switches, typically tens of volts, is much higher than the driving voltage of the complementary metal oxide semiconductor integrated circuit (∼1 V). Though the operating voltage can be reduced by adopting a narrow air gap, down to several nanometers, this leads to formidable manufacturing challenges and occasionally irreversible switch failures due to the surface adhesive force. Here, we demonstrate a new nanowire-morphed nanoelectromechanical (NW-NEM) switch structure with ultralow operation voltages. In contrast to conventional nanoelectromechanical switches actuated by unidirectional electrostatic attraction, the NW-NEM switch is bidirectionally driven by Lorentz force to allow the use of a large air gap for excellent electrical isolation, while achieving a record-low driving voltage of <0.2 V. Furthermore, the introduction of the Lorentz force allows the NW-NEM switch to effectively overcome the adhesion force to recover to the turn-off state.

4.
J Cell Mol Med ; 28(2): e18035, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37966270

RESUMO

The gold standard for determining the severity of liver disease in Fontan patients is now liver biopsy. Since it is an invasive procedure, this study determined the possibility of applying mitochondrial function from isolated peripheral blood mononuclear cells (PBMCs) as a non-invasive indicator of liver fibrosis. Fontan patients (n = 37) without known liver disease were analysed cross-sectionally. Patients were classified according to their histology using the METAVIR score as follows; F0/F1-no/mild fibrosis; F2-moderate fibrosis; and F3/F4-cirrhosis. Peripheral blood mononuclear cells were assessed for mitochondrial activity and apoptosis. This study did not find any significant differences in cardiac function among the groups according to liver histology. Interestingly, our findings indicated a significant decrease in maximal respiration and spare respiratory capacity, in both the moderate (F2) and cirrhosis (F3/F4) groups compared with the group without significant fibrosis (F0/F1). Moreover, the cirrhosis group exhibited higher levels of apoptosis and lower levels of live cells, compared with both the moderate and no significant fibrosis groups. In conclusion, the degree of liver fibrosis in Fontan patients is strongly correlated with mitochondrial dysfunction in PBMCs. Mitochondrial function and apoptosis could potentially serve as novel markers for tracking the progression of liver fibrosis in these patients.


Assuntos
Técnica de Fontan , Hepatopatias , Doenças Mitocondriais , Humanos , Técnica de Fontan/efeitos adversos , Leucócitos Mononucleares/patologia , Cirrose Hepática/patologia , Fígado/patologia , Hepatopatias/patologia , Biópsia , Índice de Gravidade de Doença , Doenças Mitocondriais/patologia
5.
Small ; 20(7): e2305494, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37797191

RESUMO

Lithium-sulfur (Li-S) batteries hold the superiority of eminent theoretical energy density (2600 Wh kg-1 ). However, the ponderous sulfur reduction reaction and the issue of polysulfide shuttling pose significant obstacles to achieving the practical wide-temperature operation of Li-S batteries. Herein, a covalent organic nanosheet-wrapped carbon nanotubes (denoted CON/CNT) composite is synthesized as an electrocatalyst for wide-temperature Li-S batteries. The design incorporates the CON skeleton, which contains imide and triazine functional units capable of chemically adsorbing polysulfides, and the underlaid CNTs facilitate the conversion of captured polysulfides enabled by enhanced conductivity. The electrocatalytic behavior and chemical interplay between polysulfides and the CON/CNT interlayer are elucidated by in situ X-ray diffraction detections and theoretical calculations. Resultantly, the CON/CNT-modified cells demonstrate upgraded performances, including wide-temperature operation ranging from 0 to 65 °C, high-rate performance (625 mAh g-1 at 5.0 C), exceptional high-rate cyclability (1000 cycles at 5.0 C), and stable operation under high sulfur loading (4.0 mg cm-2 ) and limited electrolyte (5 µL mgs -1 ). These findings might guide the development of advanced Li-S batteries.

6.
Small ; 20(12): e2307533, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37940617

RESUMO

Development of advanced electrocatalysts for the green hydrogen production by water electrolysis is an important task to reduce the climate and environmental issues as well as to meet the future energy demands. Herein, Ru/Ni-B-P sphere electrocatalyst is demonstrated by a combination of hydrothermal and soaking approaches, meeting the industrial requirement of low cell voltage with stable high-current operation. The Ru/Ni-B-P sphere catalyst demonstrates low overpotentials of 191 and 350 mV at 300 mA cm-2 with stable high current operation, ranking it as one of the best oxygen evolution reaction (OER) electrocatalysts. The bifunctional 2-E system demonstrates a low cell voltage of 2.49 V at 2000 mA cm-2 in 6 m KOH at 60 °C of harsh industrial operation condition. It also demonstrates outstanding stability with continuous 120 h (5 days) CA operation at 1000 mA cm-2. Further, the hybrid configuration of Ru/Ni-B-P || Pt/C being paired with the conventional benchmark electrode demonstrates a record low 2-E cell voltage of 2.40 V at 2000 mA cm-2 in 6 m KOH and excellent stability at high current of 1500 mA cm-2 under industrial operational condition.

7.
Small ; : e2403429, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847570

RESUMO

The lithium-ion battery industry acknowledges the need to reduce expensive metals, such as cobalt and nickel, due to supply chain challenges. However, doing so can drastically reduce the overall battery energy density, attenuating the driving range for electric vehicles. Cycling to higher voltages can increase the capacity and energy density but will consequently exacerbate cell degradation due to the instability at high voltages. Herein, an advanced localized high-concentration electrolyte (LHCE) is utilized to enable long-term cycling of a low-Ni, low-Co layered oxide cathode LiNi0.60Mn0.31Co0.07Al0.02O2 (NMCA) in full cells with graphite or graphite-silicon anodes at 4.5 V (≈4.6 vs Li+/Li). NMCA cells with the LHCE deliver a high initial capacity of 194 mA h g-1 at C/10 rate along with 73% capacity retention after 400 cycles compared to 49% retention in a baseline carbonate electrolyte. This is facilitated by reduced impedance growth, active material loss, and gas evolution with the NMCA cathode. These improvements are attributed to the formation of robust, inorganic-rich interphase layers on both the cathode and anode throughout cycling, which are induced by a favorable salt decomposition in the LHCE. This study demonstrates the efficacy of electrolytes toward facilitating the operation of high-energy-density, long-life, and cost-effective cathodes.

8.
Small ; 20(34): e2400975, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38618920

RESUMO

As electronic devices for aviation, space, and satellite applications become more sophisticated, built-in energy storage devices also require a wider temperature spectrum. Herein, an all-climate operational, energy and power-dense, flexible, in-plane symmetric pseudocapacitor is demonstrated with utmost operational safety and long cycle life. The device is constructed with interdigital-patterned laser-scribed carbon-supported electrodeposited V5O12·6H2O as a binder-free electrode and a novel high-voltage anti-freezing water-in-salt-hybrid electrolyte. The anti-freezing electrolyte can operate over a wide temperature range of -40-60 °C while offering a stable potential window of ≈2.5 V. The device undergoes rigorous testing under diverse environmental conditions, including rapid and regular temperature and mechanical transition over multiple cycles. Additionally, detailed theoretical simulation studies are performed to understand the interfacial interactions with the active material as well as the local behavior of the anti-freeze electrolyte at different temperatures. As a result, the all-weather pseudocapacitor at 1 A g-1 shows a high areal capacitance of 234.7 mF cm-2 at room temperature and maintains a high capacitance of 129.8 mF cm-2 even at -40 °C. Besides, the cell operates very reliably for over 80 950 cycles with a capacitance of 25.7 mF cm-2 at 10 A g-1 and exhibits excellent flexibility and bendability under different stress conditions.

9.
Small ; 20(24): e2306859, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38155356

RESUMO

Solution-processed and efficient yellow quantum dot light-emitting diodes (QLEDs) are considered key optoelectronic devices for lighting, display, and signal indication. However, limited synthesis routes for yellow quantum dots (QDs), combined with inferior stress-relaxation of the core-shell interface, pose challenges to their commercialization. Herein, a nanostructure tailoring strategy for high-quality yellow CdZnSe/ZnSe/ZnS core/shell QDs using a "stepwise high-temperature nucleation-shell growth" method is introduced. The synthesized CdZnSe-based QDs effectively smoothed the release stress of the core-shell interface and revealed a near-unit photoluminescence quantum yield, with nonblinking behavior and matched energy level, which accelerated radiative recombination and charge injection balance for device operation. Consequently, the yellow CdZnSe-based QLEDs exhibited a peak external quantum efficiency of 23.7%, a maximum luminance of 686 050 cd m-2, and a current efficiency of 103.2 cd A-1, along with an operating half-lifetime of 428 523 h at 100 cd m-2. To the best of the knowledge, the luminance and operational stability of the device are found to be the highest values reported for yellow LEDs. Moreover, devices with electroluminescence (EL) peaks at 570-605 nm exhibited excellent EQEs, surpassing 20%. The work is expected to significantly push the development of RGBY-based display panels and white LEDs.

10.
Small ; : e2402272, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148206

RESUMO

Despite the importance of the stability of the 2D catalysts in harsh electrolyte solutions, most studies have focused on improving the catalytic performance of molybdenum disulfide (MoS2) catalysts rather than the sustainability of hydrogen evolution. In previous studies, the vulnerability of MoS2 crystals is reported that the moisture and oxygen molecules can cause the oxidation of MoS2 crystals, accelerating the degradation of crystal structure. Therefore, optimization of catalytic stability is crucial for approaching practical applications in 2D catalysts. Here, it is proposed that monolayered MoS2 catalysts passivated with an atomically thin hexagonal boron nitride (h-BN) layer can effectively sustain hydrogen evolution reaction (HER) and demonstrate the ultra-high current density (500 mA cm⁻2 over 11 h) and super stable (64 h at 150 mA cm⁻2) catalytic performance. It is further confirmed with density functional theory (DFT) calculations that the atomically thin h-BN layer effectively prevents direct adsorption of water/acid molecules while allowing the protons to be adsorbed/penetrated. The selective penetration of protons and prevention of crystal structure degradation lead to maintained catalytic activity and maximized catalytic stability in the h-BN covered MoS2 catalysts. These findings propose a promising opportunity for approaching the practical application of 2D MoS2 catalysts having long-term stability at high-current operation.

11.
J Vasc Surg ; 80(1): 98-106, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38490605

RESUMO

OBJECTIVE: The vast majority of patients with abdominal aortic aneurysms (AAAs) undergoing repairs receive endovascular interventions (EVARs) instead of open operations (OARs). Although EVARs have better short-term outcomes, OARs have improved longer-term durability and require less radiographic follow-up and monitoring, which may have significant implications on health care economics surrounding provision of AAA care nationally. Herein, we compared costs associated with EVAR and OAR of both infrarenal and complex AAAs. METHODS: We examined patients undergoing index elective EVARs or OARs of infrarenal and complex AAAs in the 2014-2019 Vascular Quality Initiative-Vascular Implant Surveillance and Interventional Outcomes Network (VQI-VISION) dataset. We defined overall costs as the aggregated longitudinal costs associated with: (1) the index surgery; (2) reinterventions; and (3) imaging tests. We evaluated overall costs up to 5 years after infrarenal AAA repair and 3 years for complex AAA repair. Multivariable regressions adjusted for case-mix when evaluating cost differences between EVARs vs OARs. RESULTS: We identified 23,746 infrarenal AAA repairs (8.7% OAR, 91% EVAR) and 2279 complex AAA repairs (69% OAR, 31% EVAR). In both cohorts, patients undergoing EVARs were more likely to be older and have more comorbidities. The cost for the index procedure for EVARs relative to OARs was lower for infrarenal AAAs ($32,440 vs $37,488; P < .01) but higher among complex AAAs ($48,870 vs $44,530; P < .01). EVARs had higher annual imaging and reintervention costs during each of the 5 postoperative years for infrarenal aneurysms and the 3 postoperative years for complex aneurysms. Among patients undergoing infrarenal AAA repairs who survived 5 years, the total 5-year cost of EVARs was similar to that of OARs ($35,858 vs $34,212; -$223 [95% confidence interval (CI), -$3042 to $2596]). For complex AAA repairs, the total cost at 3 years of EVARs was greater than OARs ($64,492 vs $42,212; +$9860 [95% CI, $5835-$13,885]). For patients receiving EVARs for complex aneurysms, physician-modified endovascular grafts had higher index procedure costs ($55,835 vs $47,064; P < .01) although similar total costs on adjusted analyses (+$1856 [95% CI, -$7997 to $11,710]; P = .70) relative to Zenith fenestrated endovascular grafts among those that were alive at 3 years. CONCLUSIONS: Longer-term costs associated with EVARs are lower for infrarenal AAAs but higher for complex AAAs relative to OARs, driven by reintervention and imaging costs. Further analyses to characterize the financial viability of EVARs for both infrarenal and complex AAAs should evaluate hospital margins and anticipated changes in costs of devices.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Medicare , Humanos , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/economia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Procedimentos Endovasculares/economia , Procedimentos Endovasculares/efeitos adversos , Masculino , Idoso , Estados Unidos , Feminino , Fatores de Tempo , Medicare/economia , Implante de Prótese Vascular/economia , Implante de Prótese Vascular/efeitos adversos , Resultado do Tratamento , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Bases de Dados Factuais , Custos de Cuidados de Saúde , Análise Custo-Benefício , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/etiologia
12.
Strahlenther Onkol ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283342

RESUMO

PURPOSE: The present study aimed to analyze the operative duration of image-guided brachytherapy (IGBT) for cervical cancer performed at our institution. METHODS: We enrolled cervical cancer patients who had undergone tandem and ovoid-based intracavitary brachytherapy (ICBT) or intracavitary and interstitial brachytherapy (IC/ISBT) between 2020 and 2024. Cone beam computed tomography (CBCT), CT, or CT + MRI were used for IGBT. For each IGBT session, we retrospectively reviewed the following: application time (AT-defined as the duration from entry into the operating room to the initial image acquisition); planning time (PT-defined as the duration from the initial image acquisition to the start of irradiation); and total operation time (TOT- defined as the duration from entry to exit of the operating room). RESULTS: We analyzed a total of 126 sessions in 36 patients, consisting of 99 ICBT-only sessions and 27 IC/ISBT sessions. The IC/ISBT sessions had a significantly longer mean operative duration than the ICBT-only sessions. The IC/ISBT sessions with three or more interstitial needles had significantly longer AT and TOT. However, the IC/ISBT sessions with one needle showed no significant difference in operative duration compared to ICBT-only sessions. CBCT, CT, and CT + MRI were used in 42, 76, and 8 sessions, respectively. In the ICBT patients, CT + MRI had the longest PT. However, there was no significant differences in TOT among CBCT, CT, and CT + MRI. CONCLUSIONS: IC/ISBT sessions with one needle had no significant difference in operative duration compared to ICBT-only sessions. There was no significant difference in TOT between CT + MRI-based IGBT and CT-based IGBT.

13.
Biotechnol Bioeng ; 121(2): 566-579, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37986649

RESUMO

The inherent complexity of coupled biocatalytic reactions presents a major challenge for process development with one-pot multienzyme cascade transformations. Kinetic models are powerful engineering tools to guide the optimization of cascade reactions towards a performance suitable for scale up to an actual production. Here, we report kinetic model-based window of operation analysis for cellobiose production (≥100 g/L) from sucrose and glucose by indirect transglycosylation via glucose 1-phosphate as intermediate. The two-step cascade transformation is catalyzed by sucrose and cellobiose phosphorylase in the presence of substoichiometric amounts of phosphate (≤27 mol% of substrate). Kinetic modeling was instrumental to uncover the hidden effect of bulk microviscosity due to high sugar concentrations on decreasing the rate of cellobiose phosphorylase specifically. The mechanistic-empirical hybrid model thus developed gives a comprehensive description of the cascade reaction at industrially relevant substrate conditions. Model simulations serve to unravel opposed relationships between efficient utilization of the enzymes and maximized concentration (or yield) of the product within a given process time, in dependence of the initial concentrations of substrate and phosphate used. Optimum balance of these competing key metrics of process performance is suggested from the model-calculated window of operation and is verified experimentally. The evidence shown highlights the important use of kinetic modeling for the characterization and optimization of cascade reactions in ways that appear to be inaccessible to purely data-driven approaches.


Assuntos
Celobiose , Fosforilases , Celobiose/química , Glucosiltransferases/química , Glucose , Sacarose , Fosfatos
14.
BJU Int ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39224939

RESUMO

OBJECTIVE: To assess the cumulative rates of re-operations after hypospadias repair and evaluate long-term surgical outcomes at a tertiary paediatric urology centre. PATIENTS AND METHODS: Retrospective analysis of 293 boys born between 1991 and 2003 undergoing hypospadias surgery was conducted. The study included 274 patients: 165 with distal, 34 with midshaft, and 75 with proximal hypospadias. Kaplan-Meier methods were used to evaluate the re-operation data. RESULTS: The median age at primary surgery was 1.3 years, with a median follow-up of 14.4 years. The overall re-operation rate was 48.2%, with approximately half of the problems detected within the first 3 months after surgery. The risk of re-operation was correlated with hypospadias severity, with 5- and 15-year re-operation risks at 39.3% and 51.8%, respectively. Limitations of the study include its retrospective nature and variations in surgical techniques from current standards. CONCLUSION: There is a significant risk of unplanned re-operations following hypospadias repair, increasing with the severity of the original condition. This underscores the need for extended follow-up and effective communication with patients and their families about the likelihood of requiring multiple surgeries for optimal outcomes.

15.
J Surg Res ; 295: 666-672, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38113610

RESUMO

INTRODUCTION: Cancer operations are increasingly utilizing specialized equipment and technology. Related costs are often not known to the responsible surgeon. We seek to evaluate cost aspects of care episodes attributable to the surgeon's management decisions. METHODS: Financial cost data in a tertiary academic cancer center were queried over 3 y. Consecutive patients undergoing gastrointestinal operations followed by inpatient admission of two or more days were included, excluding patients with 40+ d admissions. Analysis of variance, Kruskal-Wallis, and multiple regression statistics were utilized. RESULTS: The study population included 1540 patients: 54% men and 46% women, with a median age of 64 y (range 15-95). Eight surgeons conducted major (82%) and minor (18%) operations, with a minimally invasive surgical approach in 60.4%. Procedures included colorectal (37%), pancreatic (19%), esophagogastric (18%), hepatobiliary (18%), and small bowel resections (8%). Total direct costs differed between surgeons with an analysis of variance coefficient range between -$3265 and +$6163 (P < 0.001). Surgeons' cost differences were observed for central medical supply, operating room (OR) supply, total OR, inpatient room, laboratory, pharmacy, supportive care (P < 0.001), and radiology costs (P < 0.02). OR supply cost was the dominant consistent domain with significant differences between surgeons in all case subcategories. When controlled for case category and minimally invasive surgical approach, multiple regression showed the most significant variations between surgeons in ORs, medical supply, and nutrition costs (P < 0.001), followed by laboratory costs (P < 0.01). Top OR supply costs were staplers and energy devices. CONCLUSIONS: Even in a highly subspecialized surgical environment, surgeons' variable utilization of ORs and medical supplies is strongly linked to variations in care-related costs. Specific queries into supply items should reduce costs and optimize value generated.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias , Cirurgiões , Masculino , Humanos , Feminino , Estudos Retrospectivos , Custos e Análise de Custo , Hospitalização
16.
Pharm Res ; 41(2): 375-385, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114802

RESUMO

PURPOSE: This study is focused on monitoring process parameters and quality attributes of aluminum phosphate (AlPO4) using multiple in-line probes incorporated into an industrial-scale adjuvant suspension manufacturing unit. METHODS: The manufacturing of aluminum adjuvant suspension was monitored at manufacturing scale using conductivity, turbidity, infrared, and particle sizing and count probes to follow the continuous evolution of particle formation and size distribution, and the reaction kinetics during the synthesis of AlPO4. RESULTS: The data showed that AlPO4 forms large particles at the early stages of mixing, followed by a decrease in size and then stabilization towards the later stages of mixing and pH adjustment. The results provided a complementary view of process events and assisted in optimizing several parameters, e.g., flow rate of reactants AlCl3 and Na3PO4 solutions, mixing rate, pH, and conductivity of AlPO4, as well as adjuvant quality attribute such as particle size, thus streamlining and shortening the process development stage. CONCLUSION: The results of this study showed the usefulness of the in-line probes to automate continuous assessment of AlPO4 batch-to-batch consistency during in-house adjuvant production at the industrial scale.


Assuntos
Adjuvantes Imunológicos , Compostos de Alumínio , Fosfatos , Tamanho da Partícula , Tecnologia Farmacêutica/métodos
17.
Eur J Vasc Endovasc Surg ; 68(4): 444-453, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38719137

RESUMO

OBJECTIVE: Residual aortic dissection (AD) following DeBakey type I AD repair is associated with a high rate of adverse events that need additional intervention or surgery. This study aimed to identify clinical and early post-operative computed tomography angiography (CTA) imaging factors associated with adverse events in patients with type I AD after ascending aorta replacement. METHODS: This single centre, retrospective cohort study included consecutive patients with type I AD who underwent ascending aorta replacement from January 2011 to December 2017 and post-operative CTA within three months. The primary outcome was AD related adverse events, defined as AD related death and re-operation due to aortic aneurysm or impending rupture. The location and size of the primary intimal tears, aortic diameter, and false lumen status were evaluated. Regression analyses were performed to identify factors associated with AD related adverse events. A decision tree model was used to classify patients as high or low risk. RESULTS: Of 103 participants (55.43 ± 13.94 years; 49.5% male), 24 (23.3%) experienced AD related adverse events. In multivariable Cox regression analysis, connective tissue disease (hazard ratio [HR] 15.33; p < .001), maximum aortic diameter ≥ 40 mm (HR 4.90; p < .001), and multiple (three or more) intimal tears (HR 7.12; p < .001) were associated with AD related adverse events. The three year cumulative survival free from AD related events was lower in the high risk group with aortic diameter ≥ 40 mm and multiple intimal tears (41.7% vs. 90.9%; p < .001). CONCLUSION: Early post-operative CTA findings indicating a maximum aortic diameter ≥ 40 mm and multiple intimal tears may predict a higher risk of adverse events. These findings suggest the need for careful monitoring and more vigilant management approaches in these cases.


Assuntos
Dissecção Aórtica , Angiografia por Tomografia Computadorizada , Humanos , Masculino , Feminino , Dissecção Aórtica/cirurgia , Dissecção Aórtica/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Fatores de Risco , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Resultado do Tratamento , Medição de Risco , Aneurisma Aórtico/cirurgia , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/mortalidade , Fatores de Tempo , Reoperação/estatística & dados numéricos
18.
BMC Neurol ; 24(1): 244, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009963

RESUMO

BACKGROUND: Elevated blood glucose (BG) variability has been reported as an independent risk factor for poor prognosis in a variety of diseases. This study aimed to investigate the association between BG variability and clinical outcomes in patients with spontaneous cerebellar hemorrhage (SCH) undergoing surgical operation. METHODS: This retrospective cohort study of the consecutive patients admitted to the department of Neurosurgery, the Affiliated Hospital of Qingdao University between January 2014 and June 2022 with the diagnosis of SCH underwent surgical intervention. BG analysis was continuously and routinely performed. BG variability was represented by the standard deviation (SD) of the serial measurements within the first 7 days. The general characteristics, imageological information, blood glucose level, and surgical information were reviewed and compared through medical records. RESULTS: A total of 115 patients (65 male and 50 female) were enrolled. Out of all 115 patients, the overall clinical outcomes according to the modified Rankin Scale (mRS) were poor (mRS 3-6) in 31 patients (26.96%) and good (mRS 0-2) in 84 patients (73.04%). Twelve of the 115 patients died during hospitalization, and the mortality rate was 10.43%. Multivariate logistic regression analysis showed that SD of BG (odds ratio (OR), 4.717; 95% confidence interval (CI), 1.054-21.115; P = 0.043), GCS (OR, 0.563; 95% CI, 0.330-0.958; P = 0.034), and hematoma volume (OR, 1.395; 95% CI, 1.118-1.748; P = 0.003) were significant predictors. The area under the ROC curve of SD of BG was 0.911 (95% CI, 0.850-0.973; P < 0.001) with a sensitivity and specificity of 90.3% and 83.3%, respectively, and the cut-off value was 1.736. CONCLUSIONS: High BG Variability is independently correlated with the 6-month poor outcomes in patients with SCH undergoing surgical operation.


Assuntos
Glicemia , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Glicemia/análise , Idoso , Doenças Cerebelares/cirurgia , Doenças Cerebelares/sangue , Doenças Cerebelares/diagnóstico , Doenças Cerebelares/mortalidade , Adulto , Resultado do Tratamento , Prognóstico , Hemorragias Intracranianas/sangue , Hemorragias Intracranianas/cirurgia , Hemorragias Intracranianas/diagnóstico , Hemorragias Intracranianas/mortalidade
19.
Nanotechnology ; 35(29)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608317

RESUMO

Achieving energy-efficient and high-performance field-effect transistors (FETs) is one of the most important goals for future electronic devices. This paper reports semiconducting single-walled carbon nanotube FETs (s-SWNT-FETs) with an optimized high-krelaxor ferroelectric insulator P(VDF-TrFE-CFE) thickness for low-voltage operation. The s-SWNT-FETs with an optimized thickness (∼800 nm) of the high-kinsulator exhibited the highest average mobility of 14.4 cm2V-1s-1at the drain voltage (ID) of 1 V, with a high current on/off ratio (Ion/off>105). The optimized device performance resulted from the suppressed gate leakage current (IG) and a sufficiently large capacitance (>50 nF cm-2) of the insulating layer. Despite the extremely high capacitance (>100 nF cm-2) of the insulating layer, an insufficient thickness (<450 nm) induces a highIG, leading to reducedIDand mobility of s-SWNT-FETs. Conversely, an overly thick insulator (>1200 nm) cannot introduce sufficient capacitance, resulting in limited device performance. The large capacitance and sufficient breakdown voltage of the insulating layer with an appropriate thickness significantly improved p-type performance. However, a reduced n-type performance was observed owing to the increased electron trap density caused by fluorine proportional to the insulator thickness. Hence, precise control of the insulator thickness is crucial for achieving low-voltage operation with enhanced s-SWNT-FET performance.

20.
Nanotechnology ; 35(19)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253005

RESUMO

Recently, the lead-free double perovskite Cs2AgBiBr6has been considered as a promising candidate for next-generation nonvolatile memory and artificial synapse devices due to its high stability and low toxicity compared to its lead-based counterparts. In this work, we developed a simple and effective method to produce high-quality lead-free double perovskite Cs2AgBiBr6thin films without pinholes and particles by applying a low-pressure assisted method under ambient condition with a relative humidity (RH) of about 45%. The formation of pinholes and Ag precipitation in the perovskite Cs2AgBiBr6 films is effectively suppressed by the proper ratio of N,N-dimenthylformamide (DMF) mixed in dimethyl sulfoxide (DMSO) solvents. Furthermore, the grain size of the Cs2AgBiBr6films can be significantly increased by increasing the post-annealing temperature. Finally, a sandwiched structure memristor with an ITO/Cs2AgBiBr6/Ta configuration was successfully demonstrated, featuring ultralow operation voltage (VSet∼ 57 ± 23 mV,VReset∼ -692 ± 68 mV) and satisfactory memory window (the ratio ofRHRS/RLRS∼ 10 times), which makes it suitable for low-power consumption information storage devices.

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