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1.
Nature ; 624(7992): 557-563, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913815

RESUMO

Perovskite solar cells with the formula FA1-xCsxPbI3, where FA is formamidinium, provide an attractive option for integrating high efficiency, durable stability and compatibility with scaled-up fabrication. Despite the incorporation of Cs cations, which could potentially enable a perfect perovskite lattice1,2, the compositional inhomogeneity caused by A-site cation segregation is likely to be detrimental to the photovoltaic performance of the solar cells3,4. Here we visualized the out-of-plane compositional inhomogeneity along the vertical direction across perovskite films and identified the underlying reasons for the inhomogeneity and its potential impact for devices. We devised a strategy using 1-(phenylsulfonyl)pyrrole to homogenize the distribution of cation composition in perovskite films. The resultant p-i-n devices yielded a certified steady-state photon-to-electron conversion efficiency of 25.2% and durable stability.

2.
BMC Anesthesiol ; 24(1): 70, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395779

RESUMO

BACKGROUND: Propofol formulated with medium- and long-chain triglycerides (MCT/LCT propofol) has rapidly replaced propofol formulated with long-chain triglycerides (LCT propofol). Despite this shift, the modified Marsh and Schnider pharmacokinetic models developed using LCT propofol are still widely used for target-controlled infusion (TCI) of propofol. This study aimed to validate the external applicability of these models by evaluating their predictive performance during TCI of MCT/LCT propofol in general anesthesia. METHODS: Adult patients (n = 48) undergoing elective surgery received MCT/LCT propofol via a TCI system using either the modified Marsh or Schnider models. Blood samples were collected at various target propofol concentrations and at specific time points, including the loss of consciousness and the recovery of consciousness (13 samples per patient). The actual plasma concentration of propofol was determined using high-performance liquid chromatography. The predictive performance of each pharmacokinetic model was assessed by calculating four parameters: inaccuracy, bias, divergence, and wobble. RESULTS: Both the modified Marsh and Schnider models demonstrated predictive performances within clinically acceptable ranges for MCT/LCT propofol. The inaccuracy values were 24.4% for the modified Marsh model and 26.9% for the Schnider model. Both models showed an overall positive bias, 16.4% for the modified Marsh model and 16.6% for the Schnider model. The predictive performance of MCT/LCT propofol was comparable to that of LCT propofol, suggesting formulation changes might exert only a minor impact on the reliability of the TCI system during general anesthesia. Additionally, both models exhibited higher bias and inaccuracy at target concentrations ranging from 3.5 ~ 5 ug/ml than at concentrations between 2 ~ 3 ug/ml. CONCLUSIONS: The modified Marsh and Schnider models, initially developed for LCT propofol, remain clinically acceptable for TCI with MCT/LCT propofol. TRIAL REGISTRATION: This study was registered at the Clinical Research Information Service of the Korean National Institute of Health ( https://cris.nih.go.kr ; registration number: KCT0002191; 06/01/2017).


Assuntos
Propofol , Adulto , Humanos , Propofol/farmacocinética , Anestésicos Intravenosos/farmacocinética , Reprodutibilidade dos Testes , Áreas Alagadas , Infusões Intravenosas , Anestesia Geral/métodos , Triglicerídeos
3.
Eur Spine J ; 33(5): 1957-1966, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38421447

RESUMO

PURPOSE: To identify the factors associated with a correction of the segmental angle (SA) with a total change greater than 10° in each level following minimally invasive oblique lumbar interbody fusion (MIS-OLIF). METHODS: Patients with lumbar spinal stenosis who underwent single- or two-level MIS-OLIF were reviewed. Segments with adequate correction of the SA >10° after MIS-OLIF in immediate postoperative radiograph were categorized as discontinuous segments (D segments), whereas those without such improvement were assigned as continuous segments (C segments). Clinical and radiological parameters were compared, and multivariate logistic regression analysis was performed to identify factors associated with SA correction >10° after MIS-OLIF. RESULTS: Of 211 segments included, 38 segments (18.0%) were classified as D segments. Compared with C segments, D segments demonstrated a significantly smaller preoperative SA (mean ± standard deviation [SD], - 1.1° ± 6.7° vs. 6.6° ± 6.3°, p < 0.001), larger change of SA (mean ± SD, 13.5° ± 3.4° vs. 3.1° ± 3.9°, p < 0.001), and a higher rate of presence of facet effusion (76.3% vs. 48.6%, p = 0.002). Logistic regression revealed preoperative SA (odds ratio (OR) [95% confidence interval (CI)]:0.733 [0.639-0.840], p < 0.001) and facet effusion (OR [95% CI]:14.054 [1.758-112.377], p = 0.027) as significant predictors for >10° SA correction after MIS-OLIF. CONCLUSION: Preoperative kyphotic SA and facet effusion can predict SA correction >10° following MIS-OLIF. For patients with lordotic SA and no preoperative facet effusion, supplemental procedures, such as anterior column release or posterior osteotomy, should be prepared for additional lumbar lordosis correction required for remnant global sagittal imbalance after MIS-OLIF.


Assuntos
Lordose , Vértebras Lombares , Fusão Vertebral , Estenose Espinal , Humanos , Fusão Vertebral/métodos , Estenose Espinal/cirurgia , Estenose Espinal/diagnóstico por imagem , Masculino , Feminino , Vértebras Lombares/cirurgia , Vértebras Lombares/diagnóstico por imagem , Idoso , Pessoa de Meia-Idade , Lordose/cirurgia , Lordose/diagnóstico por imagem , Estudos Retrospectivos , Resultado do Tratamento , Idoso de 80 Anos ou mais , Adulto
4.
Struct Health Monit ; 23(2): 971-990, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38405115

RESUMO

This paper proposes a framework for obstacle-avoiding autonomous unmanned aerial vehicle (UAV) systems with a new obstacle avoidance method (OAM) and localization method for autonomous UAVs for structural health monitoring (SHM) in GPS-denied areas. There are high possibilities of obstacles in the planned trajectory of autonomous UAVs used for monitoring purposes. A traditional UAV localization method with an ultrasonic beacon is limited to the scope of the monitoring and vulnerable to both depleted battery and environmental electromagnetic fields. To overcome these critical problems, a deep learning-based OAM with the integration of You Only Look Once version 3 (YOLOv3) and a fiducial marker-based UAV localization method are proposed. These new obstacle avoidance and localization methods are integrated with a real-time damage segmentation method as an autonomous UAV system for SHM. In indoor testing and outdoor tests in a large parking structure, the proposed methods showed superior performances in obstacle avoidance and UAV localization compared to traditional approaches.

5.
J Am Chem Soc ; 145(44): 24349-24357, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37883799

RESUMO

Understanding the interplay between the surface structure and the passivation materials and their effects associated with surface structure modification is of fundamental importance; however, it remains an unsolved problem in the perovskite passivation field. Here, we report a surface passivation principle for efficient perovskite solar cells via a facet-dependent passivation phenomenon. The passivation process selectively occurs on facets, which is observed with various post-treatment materials with different functionality, and the atomic arrangements of the facets determine the alignments of the passivation layers. The profound understanding of facet-dependent passivation leads to the finding of 2-amidinopyridine hydroiodide as the material for a uniform and effective passivation on both (100) and (111) facets. Consequently, we achieved perovskite solar cells with an efficiency of 25.10% and enhanced stability. The concept of facet-dependent passivation can provide an important clue on unidentified passivation principles for perovskite materials and a novel means to enhance the performance and stability of perovskite-based devices.

6.
Opt Lett ; 47(9): 2174-2177, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35486753

RESUMO

Strain-engineered graphene has garnered much attention recently owing to the possibilities of creating substantial energy gaps enabled by pseudo-magnetic fields (PMFs). While theoretical works proposed the possibility of creating large-area PMFs by straining monolayer graphene along three crystallographic directions, clear experimental demonstration of such promising devices remains elusive. Herein, we experimentally demonstrate a triaxially strained suspended graphene structure that has the potential to possess large-scale and quasi-uniform PMFs. Our structure employs uniquely designed metal electrodes that function both as stressors and metal contacts for current injection. Raman characterization and tight-binding simulations suggest the possibility of achieving PMFs over a micrometer-scale area. Current-voltage measurements confirm an efficient current injection into graphene, showing the potential of our devices for a new class of optoelectronic applications. We also theoretically propose a photonic crystal-based laser structure that obtains strongly localized optical fields overlapping with the spatial area under uniform PMFs, thus presenting a practical route toward the realization of graphene lasers.

7.
BMC Anesthesiol ; 22(1): 378, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476332

RESUMO

BACKGROUND: Previous studies have reported that the ramped position provides a better laryngoscopic view, reduces tracheal intubation time, and increases the success rate of endotracheal intubation. However, the patient's head height changes while in the ramped position, which in turn changes the relative positions of the patient and intubator. Thus, making these changes may affect the efficiency of tracheal intubation; however, few studies have addressed this problem. This study analyzed intubation time and conditions during tracheal intubation using videolaryngoscope in the ramped position. METHODS: This prospective study included 144 patients who were scheduled to receive general anesthesia for surgeries involving orotracheal intubation. The participants were randomly allocated to either the nipple or umbilical group according to the table height. Mask ventilation was assessed using the Warters grading scale. Tracheal intubation was performed using a McGrath MAC laryngoscope. The total intubation time, laryngoscopy time, tube insertion time, and difficulty of intubation (IDS score) were measured. RESULTS: The umbilical group had a significantly shorter laryngoscopy time (10 ± 3 vs. 16 ± 4 s), tube insertion time (18 ± 4 vs. 24 ± 6 s), and total intubation time (28 ± 5 vs. 40 ± 7 s) compared to the nipple group. No significant difference in the difficulty of mask ventilation was observed between the two groups. The IDS score was higher in the nipple than umbilical group. CONCLUSION: The lower (umbilical) table level reduced the intubation time and difficulty of videolaryngoscopy compared to the higher (nipple) table level. TRIAL REGISTRATION: This study was registered at KCT0005987, 11/03/2021, Retrospectively registered.


Assuntos
Intubação Intratraqueal , Mesas Cirúrgicas , Humanos , Estudos Prospectivos
8.
BMC Musculoskelet Disord ; 23(1): 573, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701803

RESUMO

BACKGROUND: We aimed (1) to clarify difference in the natural history of lumbar spinal stenosis (LSS) with respect to surgical treatment according to severity of stenosis on magnetic resonance imaging (MRI) using qualitative grading system and (2) to estimate surgical probabilities depending on radiological severity. METHODS: With the design of retrospective observational study, a total of 1,248 patients diagnosed with LSS between 2011 and 2014 at our hospital were followed up for the mean duration of 7.7 years (5.17-9.8 years). We investigated severity of central and foraminal stenoses on initial MRI using qualitative grading system and whether surgical treatment was performed. Logistic regression models were used to identify risk factors for surgery. RESULTS: During the mean follow-up period of 7.7 years, grade 3 maximal central stenosis showed the highest percentage of surgical treatment (57.9%-62.3%) with no significant difference in surgical probabilities according to concomitant foraminal stenosis. Surgical probabilities in grade 2 and 3 maximal foraminal stenosis, were 22.2%-62.3% and 33.3%-57.9%, respectively, depending on concomitant central stenosis. Maximal central stenosis of grades 1, 2, and 3 (odds ratio [OR]: 1.79, 2.21, and 6.26, respectively), and maximal foraminal stenosis of grades 2 and 3 (OR: 2.22 and 2.12, respectively) were significant risk factors for surgical treatment. CONCLUSIONS: The high grades of maximal central and foraminal stenoses were risk factors for surgical treatment. Surgical probabilities were 57.9%-62.3% in grade 3 maximal central stenosis, 22.2%-62.3% and 33.3%-57.9%, respectively, in grade 2 and 3 maximal foraminal stenosis during the mean follow-up period of 7.7 years. These results indicate that the natural history of LSS differs according to grade of maximal central and foraminal stenoses.


Assuntos
Estenose Espinal , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/patologia , Constrição Patológica/cirurgia , Seguimentos , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética/métodos , Probabilidade , Estudos Retrospectivos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/patologia , Estenose Espinal/cirurgia
9.
Opt Express ; 29(10): 14174-14181, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985141

RESUMO

The creation of CMOS compatible light sources is an important step for the realization of electronic-photonic integrated circuits. An efficient CMOS-compatible light source is considered the final missing component towards achieving this goal. In this work, we present a novel crossbeam structure with an embedded optical cavity that allows both a relatively high and fairly uniform biaxial strain of ∼0.9% in addition to a high-quality factor of >4,000 simultaneously. The induced biaxial strain in the crossbeam structure can be conveniently tuned by varying geometrical factors that can be defined by conventional lithography. Comprehensive photoluminescence measurements and analyses confirmed that optical gain can be significantly improved via the combined effect of low temperature and high strain, which is supported by a three-fold reduction of the full width at half maximum of a cavity resonance at ∼1,940 nm. Our demonstration opens up the possibility of further improving the performance of germanium lasers by harnessing geometrically amplified biaxial strain.

10.
Psychiatry Clin Neurosci ; 69(1): 43-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24902868

RESUMO

AIMS: The goal of this study was to examine the efficacy and safety of ziprasidone to treat depressive symptoms in Korean patients with schizophrenia who showed stable symptoms. METHODS: In this 8-week, open-label, prospective, non-randomized, multicenter study, 34 patients with schizophrenia who showed a stable response to previous medications, maintained a stable dose, and who had depressive symptoms, were recruited. Ziprasidone was the only antipsychotic agent allowed for 8 weeks after a 2-7-week washout period. RESULTS: Steady decreases were observed on the Montgomery-Asberg Depression Rating Scale, the Calgary Depression Scale for Schizophrenia, the Positive and Negative Syndrome Scale, and the Clinical Global Impression-Severity Scale scores. The Montgomery-Asberg Depression Rating Scale score was 20.26 ± 4.77 at baseline and 12.21 ± 7.94 at the end-point (P < 0.01). The Calgary Depression Scale for Schizophrenia score was 9.76 ± 4.11 at baseline and 5.00 ± 3.94 at the end-point (P < 0.01). The Positive and Negative Syndrome Scale total score was 75.24 ± 22.63 at baseline and 66.53 ± 24.28 at the end-point (P < 0.01). The Clinical Global Impression-Severity Scale score was 3.44 ± 0.66 at baseline and 3.15 ± 0.86 at the end-point (P < 0.05). No significant differences were observed for total scores on the Simpson and Angus Rating Scale, the Barnes Akathisia Rating Scale, or the Abnormal Involuntary Movement Scale between the baseline and end-point. CONCLUSIONS: Ziprasidone was effective for improving depressive symptom scores and was well tolerated. Switching to ziprasidone is a good strategy in patients with schizophrenia who are experiencing depressive symptoms.


Assuntos
Antipsicóticos/farmacologia , Depressão/tratamento farmacológico , Piperazinas/farmacologia , Escalas de Graduação Psiquiátrica , Esquizofrenia/tratamento farmacológico , Tiazóis/farmacologia , Adulto , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Comorbidade , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Estudos Prospectivos , Esquizofrenia/epidemiologia , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Resultado do Tratamento
11.
J Hand Surg Am ; 40(5): 883-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25746146

RESUMO

PURPOSE: To analyze the clinical outcome for delayed or suspended replantation of complete amputations of digits or hands, or both. METHODS: We analyzed 20 cases involving 28 digital and 4 hand amputations that underwent delayed or suspended replantation. In 15 cases of single-digit amputation, patients underwent delayed replantation the morning following amputation. With amputation of multiple digits, bilateral digits, or the hand, the important digits or dominant hand underwent immediate replantation, and we suspended the surgeries for the residual digits or non-dominant hand, or both, until the next morning. We then evaluated the mean warm and cold ischemic time for the operations, graft survival rates, and clinical outcomes. The mean follow-up period was 26 months. We evaluated the clinical results using the criteria of Chen. RESULTS: The mean warm and cold ischemic times in 15 cases of delayed replantation were 2 hours 4 minutes and 7 hours 21 minutes, respectively. In 8 cases of suspended replantation, the mean warm and cold ischemic times in the first operation were 5 hours 54 minutes and 2 hours 36 minutes, respectively. In the second operation, the cold ischemic time averaged 15 hours 48 minutes. In this series, 24 of 28 digits and all 4 hands survived. Total survival incidence in both delayed and suspended replantation was 88%, not statistically different from the overall survival incidence in 711 cases of immediate replantation during the same period (84%). In delayed replantation, we observed an excellent result with 6 digits and a good result with another 6 digits. In suspended cases, we observed a good result with one multiple-digit and one hand procedure and we obtained a fair result in 3 multiple-digit and 2 hand replantation procedures. CONCLUSIONS: Delayed and suspended replantations demonstrate results comparable to immediate replantation regarding graft survival and clinical outcome. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Amputação Traumática/cirurgia , Traumatismos dos Dedos/cirurgia , Traumatismos da Mão/cirurgia , Reimplante/métodos , Adulto , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
12.
Opt Lett ; 39(14): 4204-7, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25121687

RESUMO

In this Letter, we report Ge p-i-n avalanche photodetectors (APD) with low dark current (sub 1 µA below V(R)=5 V), low operating voltage (avalanche breakdown voltage=8-13 V), and high multiplication gain (440-680) by exploiting a point defect healing method (between 600°C and 650°C) and optimizing the doping concentration of the intrinsic region (p-type ~10¹7 cm⁻³). In addition, Raman spectroscopy and electrochemical capacitance voltage analyses were performed to investigate the junction interfaces in more detail. This successful demonstration of Ge p-i-n APD with low dark current, low operating voltage, and high gain is promising for low-power and high-sensitivity Ge PD applications.

13.
Asian Spine J ; 18(3): 444-457, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38146053

RESUMO

This review comprehensively examines the evolution and current state of interbody cage technology for lumbar interbody fusion (LIF). This review highlights the biomechanical and clinical implications of the transition from traditional static cage designs to advanced expandable variants for spinal surgery. The review begins by exploring the early developments in cage materials, highlighting the roles of titanium and polyetheretherketone in the advancement of LIF techniques. This review also discusses the strengths and limitations of these materials, leading to innovations in surface modifications and the introduction of novel materials, such as tantalum, as alternative materials. Advancements in three-dimensional printing and surface modification technologies form a significant part of this review, emphasizing the role of these technologies in enhancing the biomechanical compatibility and osseointegration of interbody cages. In addition, this review explores the increase in biodegradable and composite materials such as polylactic acid and polycaprolactone, addressing their potential to mitigate long-term implant-related complications. A critical evaluation of static and expandable cages is presented, including their respective clinical and radiological outcomes. While static cages have been a mainstay of LIF, expandable cages are noted for their adaptability to the patient's anatomy, reducing complications such as cage subsidence. However, this review highlights the ongoing debate and the lack of conclusive evidence regarding the superiority of either cage type in terms of clinical outcomes. Finally, this review proposes future directions for cage technology, focusing on the integration of bioactive substances and multifunctional coatings and the development of patient-specific implants. These advancements aim to further enhance the efficacy, safety, and personalized approach of spinal fusion surgeries. Moreover, this review offers a nuanced understanding of the evolving landscape of cage technology in LIF and provides insights into current practices and future possibilities in spinal surgery.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38915196

RESUMO

STUDY DESIGN: Retrospective study. OBJECTIVES: To determine the ideal pelvic incidence (PI) - lumbar lordosis (LL) range to prevent pelvic tilt (PT) undercorrection while avoiding PI-LL overcorrection following adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND: PI-LL and PT are the important sagittal parameters to be restored to an adequate range by surgery. Ideal PI-LL target without causing PI-LL overcorrection and PT undercorrection has not been documented. METHODS: We included patients with ASD undergoing ≥5-level fusion including the sacrum. Receiver operating characteristic (ROC) curve analysis was performed to calculate the lower limit of the ideal PI-LL without causing PI-LL overcorrection and the upper limit of ideal PI-LL without causing PT undercorrection. The calculated ideal PI-LL was validated in terms of proximal junctional kyphosis and failure (PJK and PJF) rates and clinical outcomes. Analyses were performed according to age subgroups (<70 and ≥70 y). RESULTS: In total, 426 patients were included in the study. Female patients were predominant (85.4%), with a mean age of 69.8 years. The lower limits of PI-LL were calculated as 4.9° for all patients, 2.3° for patients aged <70 years, and 7.9° for patients aged ≥70 years. Meanwhile, the upper limits of PI-LL were calculated as 12.7° for all patients, 12.5° for patients aged <70 years, and 13.3° for patients aged ≥70 years. There were no significant differences in the PJK and PJF rates among the new three PI-LL groups. Clinical outcomes were significantly better in patients with the ideal PI-LL group than those in patients with overcorrection or undercorrection groups for all age groups. CONCLUSION: The ideal PI-LL correction target without adversely impacting PT and PI-LL was calculated at 2.3°-12.5° for patients aged <70 years and 7.9°-13.3° for patients aged ≥70 years. These guideline parameters may help ensure optimal clinical outcomes without increasing the risk of PJK/F.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38956981

RESUMO

STUDY DESIGN: Retrospective study. OBJECTIVE: We sought to compare surgical outcomes according to baseline balance statuses in elderly patients with degenerative sagittal imbalance (DSI). SUMMARY OF BACKGROUND: Although optimal sagittal correction has been emphasized for good surgical outcomes, the effect of the state of preoperative balance on surgical outcome has been adequately described at present. METHODS: Patients aged ≥60 years with DSI who underwent ≥5-level fusion to the sacrum were included. Among them, only those who postoperatively achieved the optimal age-adjusted pelvic incidence (PI) - lumbar lordosis (LL) target were included in this study. Study participants were divided into two groups according to their preoperative sagittal vertical axis (SVA): compensatory balance (SVA <5 cm, group CB) and decompensation (SVA ≥5 cm, group D). Comparisons between the two groups were performed using the chi-squared test or Fisher's exact test for categorical variables and the independent t- test or Wilcoxon rank- sum test for continuous variables. RESULTS: A total of 156 patients whose postoperative sagittal alignment matched the age-adjusted PI-LL target constituted the study cohort. There were 59 patients in group CB and 97 patients in group D. Mean follow-up duration was 50.0 months after surgery. Immediate postoperatively, sacral slope and SVA were significantly greater in group D than in group CB. At last follow-up, the SVA was significantly greater in group D than in group CB (43.6 vs. 22.7 mm), while no significant differences were found in other sagittal parameters. The Oswestry disability index and Scoliosis Research Society -22 scores at the last follow-up were significantly worse in group D than in group CB. CONCLUSION: The SVA tended to experience less correction postoperatively, with evidence of further deterioration during follow-up in group D than in group CB. This suboptimal correction of SVA may contribute to the inferior clinical outcomes encountered in group D relative to group CB. Therefore, we recommend correction of PI-LL as close as possible to the lower limit of the suggested PI-LL target range in patients with evidence of preoperative decompensation.

16.
Int J Biol Macromol ; 254(Pt 3): 127236, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37797861

RESUMO

This study investigated the impact of cellulose nanofibers (CNFs) on montmorillonites (MMTs) exfoliation within thermoplastic starch (TPS) nanocomposites during the melt blending process. TPS nanocomposite films were manufactured using an internal mixer with a controlled ratio of CNFs and MMTs to evaluate the effect of individual and hybrid fillers on the material interactions and characteristics of the TPS composites. The incorporation of hybrid fillers resulted in notable enhancements in torque values and rheological properties, suggesting interactions between the starch, CNFs, and MMTs. The degree of MMT intercalation, obtained via X-ray diffraction analysis, decreased with the addition of CNFs, indicating that CNFs positively impacted MMT exfoliation. Scanning electron microscopy (SEM) images of cryo- and tensile-fractured samples highlighted the effectiveness of CNFs in facilitating MMT exfoliation and reinforcing interactions between the MMTs and TPS matrix. These interactions enhanced the tensile strength and Young's modulus by up to 95.8 % and 278.2 %, respectively, with a 1:1 weight ratio of CNFs to MMTs. Additionally, well-dispersed MMTs within the TPS matrix caused passivation and created tortuous paths, improving the water contact angle and decreasing the water vapor sorption. These synergistic effects of the hybrid filler, achieved through a melt blending process, indicate the potential use of TPS nanocomposites as an eco-friendly packaging material.


Assuntos
Nanocompostos , Nanofibras , Amido , Celulose , Bentonita , Excipientes , Resistência à Tração
17.
Neurosurgery ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934636

RESUMO

BACKGROUND AND OBJECTIVES: Appropriate correction relative to the age-adjusted sagittal alignment target reduces the proximal junctional failure (PJF) risk. Nonetheless, a considerable number of patients suffer from PJF despite optimal correction. The aim of this study was to identify the risk factors of PJF that occurs despite optimal correction relative to the sagittal age-adjusted score (SAAS) in adult spinal deformity surgery. METHODS: Patients aged 60 years or older with adult spinal deformity who underwent ≥5-level fusion to the sacrum were initially screened. Among them, only patients who achieved optimal sagittal correction relative to the SAAS were included in the study. Optimal correction was defined as the SAAS point between -1 and +1. Various clinical and radiographic factors were compared between the PJF and no PJF groups and were further evaluated using multivariate analysis. RESULTS: The final study cohort comprised 127 patients. The mean age was 67 years, and there were 111 women (87.4%). A mean of total fusion length was 7.2. PJF occurred in 42 patients (33.1%), while 85 patients (66.9%) did not develop PJF. Multivariate analysis showed that a high body mass index (odds ratio [OR] = 1.153, 95% CI = 1.027-1.295, P = .016), a higher lordosis distribution index (LDI) (OR = 1.024, 95% CI = 1.003-1.045, P = .022), and no use of hook fixation (OR = 9.708, 95% CI = 1.121-76.923, P = .032) were significant risk factors of PJF development. In the receiver operating characteristic curve analysis, the cutoff value for the LDI was calculated as 61.0% (area under the curve = 0.790, P < .001). CONCLUSION: PJF developed in a considerable portion of patients despite optimal correction relative to the age-adjusted alignment. The risk factors of PJF in this patient group were high body mass index, high LDI exceeding 61%, and no use of hook fixation. PJF could be further decreased by properly managing these risk factors along with optimal sagittal correction.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38190679

RESUMO

Accurate and continuous bladder volume monitoring is crucial for managing urinary dysfunctions. Wearable ultrasound devices offer a solution by enabling non-invasive and real-time monitoring. Previous studies have limitations in power consumption and computation cost or quantitative volume estimation capability. To alleviate this, we present a novel pipeline that effectively integrates conventional feature extraction and deep learning to achieve continuous quantitative bladder volume monitoring efficiently. Particularly, in the proposed pipeline, bladder shape is coarsely estimated by a simple bladder wall detection algorithm in wearable devices, and the bladder wall coordinates are wirelessly transferred to an external server. Subsequently, a roughly estimated bladder shape from the wall coordinates is refined in an external server with a diffusion-based model. With this approach, power consumption and computation costs on wearable devices remained low, while fully harnessing the potential of deep learning for accurate shape estimation. To evaluate the proposed pipeline, we collected a dataset of bladder ultrasound images and RF signals from 250 patients. By simulating data acquisition from wearable devices using the dataset, we replicated real-world scenarios and validated the proposed method within these scenarios. Experimental results exhibit superior improvements, including +9.32% of IoU value in 2D segmentation and -22.06 of RMSE in bladder volume regression compared to state-of-the-art performance from alternative methods, emphasizing the potential of this approach in continuous bladder volume monitoring in clinical settings. Therefore, this study effectively bridges the gap between accurate bladder volume estimation and the practical deployment of wearable ultrasound devices, promising improved patient care and quality of life.

19.
Neurospine ; 21(2): 721-731, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38955541

RESUMO

OBJECTIVE: To determine the clinical impact of the baseline sagittal imbalance severity in patients with adult spinal deformity (ASD). METHODS: We retrospectively reviewed patients who underwent ≥ 5-level fusion including the pelvis, for ASD with a ≥ 2-year follow-up. Using the Scoliosis Research Society-Schwab classification system, patients were classified into 3 groups according to the severity of the preoperative sagittal imbalance: mild, moderate, and severe. Postoperative clinical and radiographic results were compared among the 3 groups. RESULTS: A total of 259 patients were finally included. There were 42, 62, and 155 patients in the mild, moderate, and severe groups, respectively. The perioperative surgical burden was greatest in the severe group. Postoperatively, this group also showed the largest pelvic incidence minus lumbar lordosis mismatch, suggesting a tendency towards undercorrection. No statistically significant differences were observed in proximal junctional kyphosis, proximal junctional failure, or rod fractures among the groups. Visual analogue scale for back pain and Scoliosis Research Society-22 scores were similar across groups. However, severe group's last follow-up Oswestry Disability Index (ODI) scores significantly lower than those of the severe group. CONCLUSION: Patients with severe sagittal imbalance were treated with more invasive surgical methods along with increased the perioperative surgical burden. All patients exhibited significant radiological and clinical improvements after surgery. However, regarding ODI, the severe group demonstrated slightly worse clinical outcomes than the other groups, probably due to relatively higher proportion of undercorrection. Therefore, more rigorous correction is necessary to achieve optimal sagittal alignment specifically in patients with severe baseline sagittal imbalance.

20.
Biomater Sci ; 12(6): 1536-1548, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38299265

RESUMO

Imaging-guided diagnosis and treatment of cancer hold potential to significantly improve therapeutic accuracies and efficacies. Central to this theragnostic approach has been the use of multicomponent-based multimodal nanoparticles (NPs). Apart from this conventional approach, here we propose a design strategy for the simple and straightforward formulation of NPs based on boron dipyrromethene (BODIPY) derivatives, LaB-X (X = H, Et, and Br). Specifically, the conjugation of lactose to the inherently hydrophobic BODIPY promoted the formation of LaB-X NPs in water. Furthermore, the BODIPY backbone was subjected to distyrylation, dibromination, and diethylation to tailor the optical window and the balance between fluorescence and singlet oxygen generation capabilities. We demonstrate that while the photoinduced anticancer activities of LaB-H and LaB-Et NPs were trivial, LaB-Br NPs effectively induced the apoptotic death of hepatocellular carcinoma cells under red light irradiation while allowing fluorescence cell imaging in the phototherapeutic window. This dual fluorescence photosensitizing activity of LaB-Br NPs could be switched off and on, so that both fluorescence and singlet oxygen generation were paused during NP formation in an aqueous solution, while both processes resumed after cellular uptake, likely due to NP disassembly.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Oxigênio Singlete , Fotoquimioterapia/métodos , Compostos de Boro/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Corantes , Nanopartículas/química , Fármacos Fotossensibilizantes/química
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