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1.
World J Surg Oncol ; 21(1): 197, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403056

RESUMO

BACKGROUND: This study compared the survival outcomes of abdominal radical hysterectomy (ARH) (N = 32), laparoscopic radical hysterectomy (LRH) (N = 61), robot-assisted radical hysterectomy (RRH) (N = 100) and vaginal radical hysterectomy (VRH) (N = 45) approaches for early-stage cervical cancer to identify the surgical approach that provides the best survival. METHODS: Disease-free survival (DFS) and overall survival (OS) were calculated using the Kaplan-Meier method, and survival curves were compared using the log-rank test. RESULTS: The volume of intraoperative blood loss was greater in the ARH group than in the LRH group, the RRH group or the VRH group [(712.50 ± 407.59) vs. (224.43 ± 191.89), (109.80 ± 92.98) and (216.67 ± 176.78) ml, respectively; P < 0.001]. Total 5-year OS was significantly different among the four groups (ARH, 96.88%; LRH, 82.45%; RRH, 94.18%; VRH, 91.49%; P = 0.015). However, no significant difference in 5-year DFS was observed among the four groups (ARH, 96.88%; LRH, 81.99%; RRH, 91.38%; VRH, 87.27%; P = 0.061). CONCLUSION: This retrospective study demonstrated that ARH and RRH achieved higher 5-year OS rates than LRH for early-stage cervical cancer.


Assuntos
Laparoscopia , Robótica , Neoplasias do Colo do Útero , Feminino , Humanos , Estudos Retrospectivos , Robótica/métodos , Neoplasias do Colo do Útero/patologia , Estadiamento de Neoplasias , Histerectomia/métodos , Laparoscopia/métodos
2.
Small ; 15(38): e1901793, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31379110

RESUMO

Band-like transport behavior of H-doped transition metal dichalcogenide (TMD) channels in field effect transistors (FET) is studied by conducting low-temperature electrical measurements, where MoTe2 , WSe2 , and MoS2 are chosen for channels. Doped with H atoms through atomic layer deposition, those channels show strong n-type conduction and their mobility increases without losing on-state current as the measurement temperature decreases. In contrast, the mobility of unintentionally (naturally) doped TMD FETs always drops at low temperatures whether they are p- or n-type. Density functional theory calculations show that H-doped MoTe2 , WSe2 , and MoS2 have Fermi levels above conduction band edge. It is thus concluded that the charge transport behavior in H-doped TMD channels is metallic showing band-like transport rather than thermal hopping. These results indicate that H-doped TMD FETs are practically useful even at low-temperature ranges.

3.
Sci Total Environ ; 947: 174680, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38992363

RESUMO

Forest management pathways for nature-based climate solutions, such as variable retention harvesting (VRH), have been gaining traction in recent years; however, their net biochemical and biophysical impacts remain unknown. Here, we use a combination of close-range and satellite remote sensing, eddy covariance technique, and ground-based biometric measurements to investigate forest thinning density and aggregation that maintain ecosystem nutrients, enhance tree growth and provide a negative feedback to the local climate in a northern temperate coniferous forest stand in Ontario, Canada. Our results showed that soil carbon (C) and nitrogen (N) in VRH plots were significantly lower (p < 0.05) for all VRH treatments compared to unharvested plots. On average, soil C was reduced by -0.64 ± 0.22 Δ% C and N by -0.023 ± 0.008 Δ% N in VRH plots. We also observed the largest loss of soil C and N in open areas of aggregate plots. Furthermore, the changes in albedo resulting from VRH treatment were equivalent to removing a large amount of C from the atmosphere, ranging from 1.3 ± 0.2 kg C yr-1 m-2 in aggregate 33 % crown retention plots to 3.4 ± 0.5 kg C yr-1 m-2 in dispersed 33 % crown retention plots. Our findings indicate that spatially dispersed VRH resulted in minimal loss of soil C and N and the highest understory growth and C uptake, while enhanced tree growth and local cooling through increased albedo were observed in dispersed VRH plots with the fewest residual trees. These findings suggest that using the harvested trees from VRH in a way that avoids releasing C into the atmosphere makes dispersed VRH the preferred forest management pathway for nature-based climate solutions.

4.
ACS Appl Mater Interfaces ; 15(10): 13299-13306, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36856371

RESUMO

The existence of a novel phenomenon, such as the metal-insulator transition (MIT) in two-dimensional (2D) systems, affords emerging functional properties that provide new aspects for future electronics and optoelectronics. Here, we report the observation of the MIT in black phosphorus field effect transistors by tuning the carrier density (n) controlled by back-gate bias. We find that the conductivity follows an n dependence as σ(n) ∝ nα with α ∼ 1, which indicates the presence of screened Coulomb impurity scattering at high carrier densities in the temperature range of 10-300 K. As n decreases, the screened Coulomb impurity scattering breaks down, developing strong charge density inhomogeneity leading to a percolation-based transition at the critical carrier density (nC). At low carrier densities (n < nC), the system is in the insulating regime, which is expressed by Mott variable range hopping that demonstrates the role of disorder in the system. In addition, the extracted average values of critical exponent δ are ∼1.29 ± 0.01 and ∼1.14 ± 0.01 for devices A and B, respectively, consistent with the 2D percolation exponent of 4/3, confirming the 2D percolation-based MIT in BP devices. Our findings strongly suggest that the 2D MIT observed in BP is a classical percolation-based transition caused by charge inhomogeneity induced by screened Coulomb charge impurity scattering around a transition point controlled by n through back-gate bias.

5.
J Thorac Dis ; 14(9): 3205-3210, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36245621

RESUMO

Background: Patients undergoing flexible bronchoscopy under local anesthesia usually experience anxiety before and during the procedure. Different non-pharmacological techniques, including music and hypnosis, are used to distract patients' attention, and to reduce anxiety. The new technique "virtual reality hypnosis (VRH)", defined as a hypnotic induction suggestion delivered by personalized virtual reality software, can generate a simulation of a lifelike environment. No study has described the use of VRH during bronchoscopy. The objective is to investigate the anxiety reducing effect and the satisfaction of patients, physicians, and nurses using VRH during bronchoscopy. Methods: VRH was proposed to all patients who experienced anxiety before undergoing flexible bronchoscopy under local anesthesia. Local anesthesia was performed using 5% lidocaine spray only. No sedation was used. After the procedure, patients, physicians and nurses filled a standardized satisfaction form. Results: Twenty consecutive patients who reported pre-procedure anxiety were included. The sex ratio was 16 women/4 men, the median age was 65 years. Eight patients (40%) had undergone a previous bronchoscopy under local anesthesia. The median duration of the procedure was 10 minutes, and all procedures were completed. The median level of anxiety of patients decreased from 9/10 before the procedure to 4/10 during the procedure. The median satisfaction rate regarding the use of VRH was 10/10. All patients agreed to use VRH again in case of a new bronchoscopy procedure. Conclusions: This preliminary report has shown that VRH was useful to reduce patients' anxiety during bronchoscopy under local anesthesia. VRH was easily implemented in the routine practice.

6.
Nanomaterials (Basel) ; 12(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36014709

RESUMO

Graphene oxides with different degrees of oxidation are prepared by controlling UV irradiation on graphene, and the charge transport and the evolution of the transport gap are investigated according to the extent of oxidation. With increasing oxygenous defect density nD, a transition from ballistic to diffusive conduction occurs at nD≃1012 cm-2 and the transport gap grows in proportion to nD. Considering the potential fluctuation related to the e-h puddle, the bandgap of graphene oxide is deduced to be Eg≃30nD(1012cm-2) meV. The temperature dependence of conductivity showed metal-insulator transitions at nD≃0.3×1012 cm-2, consistent with Ioffe-Regel criterion. For graphene oxides at nD≥4.9×1012 cm-2, analysis indicated charge transport occurred via 2D variable range hopping conduction between localized sp2 domain. Our work elucidates the transport mechanism at different extents of oxidation and supports the possibility of adjusting the bandgap with oxygen content.

7.
Materials (Basel) ; 15(14)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35888231

RESUMO

Pure bismuth ferrite (BFO) and BFO with impurity phases (Bi2O3 or Fe2O3) were synthesized by the hydrothermal method. Complex dielectric permittivity (ε) and electrical conductivity (σ) were determined by complex impedance measurements at different frequencies (200 Hz-2 MHz) and temperatures (25-290) °C. The conductivity spectrum of samples, σ(f), complies with Jonscher's universal law and the presence of impurity phases leads to a decrease in the static conductivity (σDC); this result is correlated with the increased thermal activation energy of the conduction in impure samples compared to the pure BFO sample. The conduction mechanism in BFO and the effect of impurity phases on σ and ε were analyzed considering the variable range hopping model (VRH). Based on the VRH model, the hopping length (Rh), hopping energy (Wh) and the density of states at the Fermi level (N(EF)) were determined for the first time, for these samples. In addition, from ε(T) dependence, a transition in the electronic structure of samples from a semiconductor-like to a conductor-like behavior was highlighted around 465-490 K for all samples. The results obtained are useful to explain the conduction mechanisms from samples of BFO type, offering the possibility to develop a great variety of electrical devices with novel functions.

8.
J Phys Condens Matter ; 33(31)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34132205

RESUMO

GaxZn1-xO thin films with varying Ga fraction within the solubility limit were irradiated with high-energy heavy ions to induce electronic excitations. The films show good transmittance in the visible region and a reduction of about 20% in transmittance was observed for irradiated films at higher ion fluences. The Urbach energy was estimated and showed an augmenting response upon increase in doping fraction and ion irradiation, this divulges an enhancement of localized states in the bandgap or disorder in the films. The evolution of such localized states plays a vital role in charge transport and thus the temperature dependent electrical conductivity of irradiated thin films was studied to elucidate the dominant conduction mechanisms. The detailed analysis unfolds that in the high-temperature regime (180 K

9.
J Phys Condens Matter ; 33(33)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34049299

RESUMO

Iridium-based double perovskites having mixed 3d-5d-4fmagnetic sub-lattices are expected to exhibit exotic magnetic phenomenon. In this paper, we report a study of structural, magnetic and transport properties of the mixed 3d-5d-4fdouble perovskite Sm2CoIrO6(SMCO), which crystallizes in monoclinic structure with space groupP21/nand the crystal symmetry remains same throughout the measured temperature down to 15 K. High resolution synchrotron x-ray diffraction reveals an isostructural phase transition around 104 K. Magnetization measurements on polycrystalline samples indicate that SMCO orders ferrimagnetically atTFiM= 104 K; while, a second transition is observed below 10 K due to the rare-earth (Sm3+) ordering. The ferrimagnetic transition is well-understood by Néel's two-sublattice model, which is primarily ascribed to antiferromagnetic coupling between Co2+and Ir4+sub-lattices. Electronic transport measurement shows the insulting behaviour of SMCO, which follows Mott variable-range hopping conduction mechanism. However, dielectric measurements as a function of temperature rules out the presence of magneto dielectric coupling in this compound.

10.
Methodist Debakey Cardiovasc J ; 14(2): e1-e3, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30038700

RESUMO

Venous retroperitoneal hematoma (VRH) can present as a sudden-onset life-threatening condition. Unlike arterial hematoma, VRH is difficult to treat because of anatomic and structural considerations. Moreover, because VRH is rare and iatrogenic, there are no commercially available devices to treat this problem. We present a novel use of aortic stent graft components to treat a large, life-threatening VRH.


Assuntos
Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Hematoma/cirurgia , Veia Ilíaca/cirurgia , Stents , Lesões do Sistema Vascular/cirurgia , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Humanos , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/lesões , Masculino , Pessoa de Meia-Idade , Flebografia , Desenho de Prótese , Espaço Retroperitoneal , Resultado do Tratamento , Lesões do Sistema Vascular/complicações , Lesões do Sistema Vascular/diagnóstico por imagem
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