Low-voltage and fast-response SnO2nanotubes/perovskite heterostructure photodetector.

One-dimensional metal-oxides (1D-MO) nanostructure has been regarded as one of the most promising candidates for high-performance photodetectors due to their outstanding electronic properties, low-cost and environmental stability. However, the current bottlenecks are high energy consumption and relatively low sensitivity. Here, Schottky junctions between nanotubes (NTs) and FTO were fabricated by electrospinning SnO2NTs on FTO glass substrate, and the bias voltage of SnO2NTs photodetectors was as low as ∼1.76 V, which can effectively reduce energy consumption. Additionally, for improving the response and recovery speed of SnO2NTs photodetectors, the NTs were covered with organic/inorganic hybrid perovskite. SnO2NTs/perovskite heterostructure photodetectors exhibit fast response/recovery speed (∼0.075/0.04 s), and a wide optical response range (∼220-800 nm). At the same time, the bias voltage of heterostructure photodetectors was further reduced to 0.42 V. The outstanding performance is mainly attributed to the formation of type-II heterojunctions between SnO2NTs and perovskite, which can facilitate the separation of photogenerated carriers, as well as Schottky junction between SnO2NTs and FTO, which reduce the bias voltage. All the results indicate that the rational design of 1D-MO/perovskite heterostructure is a facile and efficient way to achieve high-performance photodetectors.

High Annealing Stability of InAlZnO Nanofiber Field-Effect Transistors with Improved Morphology by Al Doping.

In2O3 nanofibers usually suffer a high off-current and consequent low on/off current ratio, as well as a large negative threshold voltage (Vth). Furthermore, regarding Zn doped binary-cation In2O3 nanofibers, severe thermal diffusion of Zn elements can result in deteriorated electrical performance when annealed at high temperature. Here, we applied an electrospinning technique to obtain ternary-cation IAZO nanofibers with controllable Vth and chemical stoichiometry. The presence of the Al element in IAZO nanofibers can lead to more superior microstructure with improved uniformity, lower surface defect, and superior metal-oxide-metal lattice at high annealing temperature. Consequently, our Al-doped ternary-cation IAZO devices exhibited an improved on/off current ratio of 107 and a high electron mobility of ∼10 cm2 V-1 s-1. Moreover, the electron mobility can be increased to 30 cm2 V-1 s-1 in our low-voltage operated FETs with high-k AlOx as the dielectric layer, which can be envisioned to exhibit vast implications for high-performance transparent electronics.

The Predictive and Prognostic Factors in Patients with Gastric Cancer Accompanied by Gastric Outlet Obstruction.

PURPOSE: This study is aimed at evaluating the clinicopathological features and prognostic significance of gastric outlet obstruction (GOO) in patients with distal gastric cancer. METHODS: A retrospective review of 1564 individuals with distal gastric cancer from 2002 to 2010 was performed. In total, 157 patients had GOO. The clinicopathological features of the patients with GOO were compared with those of the patients without GOO. A Kaplan-Meier survival analysis and Cox proportional hazard model were used to assess the overall survival. RESULTS: The patients with distal gastric cancer with GOO generally presented more aggressive pathologic features, a poorer nutritional status, more duodenal infiltration, and peritoneal dissemination than those with cancer without GOO. In the univariate analysis, curability, GOO, age, prealbumin, albumin, hemoglobin (Hb), the tumor size, the macroscopic type, lymph node metastasis, and the depth of invasion had a statistically significant influence on prognosis. The multivariate analysis showed that curability, GOO, the tumor size, lymph node metastasis, and the depth of invasion were independent prognostic factors. CONCLUSIONS: Gastric cancer with GOO exhibits aggressive biological features and has poor outcomes. The multivariate analysis showed that curability, GOO, the tumor size, lymph node metastasis, and the depth of invasion were independent prognostic factors. The gastric outlet status should be considered in the selection of surgical treatment methods for patients with gastric cancer.

Modulating electrical and photoelectrical properties of one-step electrospun one-dimensional SnO2 arrays.

One-dimensional nanostructured SnO2 has attracted intense research interest due to its advantageous properties, including a large surface-to-volume ratio, high optical transparency and typical n-type properties. However, how to fabricate high-performance and multifunctional electronic devices based on 1D nanostructured SnO2 via low-cost and efficient preparation techniques is still a huge challenge. In this work, a low-cost, one-step electrospun technology was employed to synthesize the SnO2 nanofiber (NF) and nanotube (NT) arrays. The electrical and photoelectrical parameters of SnO2 NTs-based devices were effectively controlled through simple changes to the amount of Sn in the precursor solution. The optimal 0.2 SnO2 NTs-based field effect transistors (FETs) with 0.2 g SnCl2*4H2O per 5 ml in the precursor solution exhibit a high saturation current (∼9 × 10-5 A) and a large on/off ratio exceeding 2.4 × 106. Additionally, 0.2 SnO2 NTs-based FET also exhibit a narrowband deep-UV photodetectivity (240-320 nm), including an ultra-high photocurrent of 307 µA, a high photosensitivity of 2003, responsibility of 214 A W-1 and detectivity of 2.19 × 1013 Jones. Furthermore, the SnO2 NTs-based transparent photodetectors were as well be integrated with fluorine-doped tin oxide glass and demonstrated a high optical transparency and photosensitivity (∼199). All these results elucidate the significant advantages of these electrospun SnO2 NTs for next-generation multifunctional electronics and transparent photonics.

Preoperative prealbumin levels on admission as an independent predictive factor in patients with gastric cancer.

BACKGROUND: To explore the role of preoperative prealbumin levels in predicting the prognosis of patients with gastric cancer. METHODS: A total of 989 gastric cancer patients in the Affiliated Tumour Hospital of Harbin Medical University who underwent gastrectomy were included in this retrospective study. The preoperative prealbumin level, clinicopathological data, and follow-up data were recorded. According to the maximum chi-square survival correlation value, the survival of patients with low preoperative prealbumin (<140 mg/L) and high preoperative prealbumin (≥140 mg/L) were compared using the log-rank test and the Cox proportional hazard regression model. RESULTS: Based on the best cut-off value of 140 mg/L, we divided the patients into the lower prealbumin group (<140 mg/L) and the higher prealbumin group (≥140 mg/L). Compared with the higher prealbumin group, the lower prealbumin group were older and had larger tumor volumes, lower hemoglobin (Hb) levels, and more upper gastric cancer tumors. The univariate analysis showed that prealbumin and other clinicopathological factors, including age, hemoglobin, tumor size, macroscopic type, cell differentiation, liver metastasis, operation type, N stage, and T stage, were significant prognostic factors. The multivariable analysis showed that age, prealbumin, macroscopic type, location, T stage, and N stage were independent prognostic factors. CONCLUSIONS: The preoperative prealbumin level was an independent prognostic factor for patients with gastric cancer. The preoperative prealbumin level can be used to predict the prognosis of patients with gastric cancer and guide clinical practice.

Patient-specific probabilistic atlas combining modified distance regularized level set for automatic liver segmentation in CT.

Liver segmentation from CT is regarded as a prerequisite for computer-assisted clinical applications. However, automatic liver segmentation technology still faces challenges due to the variable shapes and low contrast. In this paper, a patient-specific probabilistic atlas (PA)-based method combing modified distance regularized level set for liver segmentation is proposed. Firstly, the similarities between training atlases and testing patient image are calculated, resulting in a series of weighted atlas, which are used to generate the patient-specific PA. Then, a most likely liver region (MLLR) can be determined based on the patient-specific PA. Finally, the refinement is performed by the modified distance regularized level set model, which takes advantage of both edge and region information as balloon force. We evaluated our proposed scheme based on 35 public datasets, and experimental result shows that the proposed method can be deployed for robust and precise liver segmentation, to replace the tedious and time-consuming manual method.

Clinico-pathological features and prognostic analysis of gastric cancer patients in different age groups.

BACKGROUND/AIMS: The prognostic value of age on patients with gastric cancer is not well defined. The aim of this retrospective study is to analyze the impact of age on survival in patients with gastric cancer. METHODOLOGY: A total of 1800 patients with gastric carcinoma, who had undergone gastrectomy between 1997-2007 years were included. They were divided into six different age groups (21-30, 31-40, 41-50, 51- 60, 61-70 and 71-80 years). We reviewed patient's clinico-pathological characteristics and the prognosis with special reference to their ages. RESULTS: Among the six age groups, the younger patients have more female-dominated patients and poorly differentiated carcinoma, whereas the older patients have a higher incidence of large tumors (≥5 cm) and more patients with stage T3. Moreover, there were more liver metastases in the older age groups. Univariate analysis showed that there were significant differences in 5-year survival rates among the six age groups. Multivariate analysis confirmed age, tumor size, pT stage, pN stage and curability were independent prognostic factors. CONCLUSION: There are several distinctive properties related to age of patients with gastric cancer, the older patients have more aggressive features and poorer prognosis than the younger patients.

Clinical investigation of combined Billroth II with Braun anastomosis for patients with gastric cancer.

BACKGROUND/AIMS: This study gives insight into the effect of combined Billroth II with Braun anastomosis for patients with gastric cancer. METHODOLOGY: The clinical data of 720 patients with gastric cancer who underwent surgical treatment in our hospital from 1997 to 2011 were reviewed retrospectively. The results of different operative approaches were analyzed. RESULTS: Combined Billroth II with Braun anastomosis was performed in 378 cases, and Billroth II in 342 cases. The Gastrointestinal Quality of Life Index (GIQLI) was used to evaluate postoperative quality of life. CONCLUSIONS: If the indications for combined Billroth II with Braun anastomosis are strictly controlled, and more attention is paid to perioperatively support, combined Billroth II with Braun anastomosis can prolong the life span of the patients with gastric cancer rather than increase the surgical complications and the mortality.

Clinicopathologic characteristics and prognostic value of various histological types in advanced gastric cancer.

The prognostic value of histological types in gastric cancer is not well defined. This study aims to clarify the clinicopathologic features of various WHO histological types and their prognostic significance in advanced gastric cancer (AGC). We retrospectively reviewed 741 patients with gastric cancer in our hospital from 1997 to 2007. The AGC (741 cases) were divided into five histological types: well-differentiated carcinoma (WD), moderately differentiated carcinoma (MD), poorly differentiated carcinoma (PD), mucinous carcinoma (MC), and signet ring cell carcinoma (SRC). The various AGC histological types presented significant differences in their clinical and tumor features. The five-year survival rates of patients with WD, MD, PD, MC, and SRC were 87.1%, 57.1%, 50.6%, 62.7%, and 43.4%, respectively (P=0.012). Multivariate analysis showed that cell differentiation, age, depth of invasion, and lymph node metastasis were independent prognostic factors in AGC, whereas MC and SRC were not. Cell differentiation is related to tumor aggression or patient stage. Advanced stage SRC carcinoma had more aggressive features and worse prognosis than the other types. MC carcinoma survival is correlated with the stage at diagnosis. The degree of cell differentiation is an important predictor of survival in AGC.

Clinicopathologic characteristics and prognosis of gastric cancer patients underwent gastrectomy combined with splenectomy.

BACKGROUND/AIMS: This study gives insight into the effect of splenectomy in radical surgery for gastric cancer. METHODOLOGY: The study included 631 patients who underwent radical resection for gastric cancer. Of these 631 patients, 105 underwent splenectomy and 526 had splenic preservation. The clinicopathologic features of 105 patients underwent gastrectomy combined with resection of the spleen (splenectomy group) and 526 patients underwent gastrectomy (spleen-preservation group) were compared. RESULTS: Gastric cancer with splenectomy was characterized by tumor located in gastric cardia (33.3%), positive lymph node metastasis (91.4%), and serosal invasion (94.3%). For age, gender, and tumor size, there was no significant difference between the patients with splenectomy and spleen-preservation. The 5-year survival of splenectomy group was 21.3% as compared with 38.6% for spleen-preservation group (P<0.001). With respect to patients with splenectomy, multivariate analysis showed that lymph node metastasis was significant factors affecting survival. CONCLUSIONS: Compared with spleen-preservation group, patients who underwent gastrectomy combined with splenectomy have a greater chance of tumor located in gastric cardia, positive lymph node metastasis, and serosal invasion and a significantly poor prognosis.

A New Subclassification of pT4 Gastric Cancers According to the Width of Serosal Invasion.

OBJECTIVE: The purpose of this study was to propose a novel subclassification of pT4 gastric cancers according to the width of serosal changes and to investigate the validity and clinical utility of this subclassification as a predictor of prognosis. METHODS: A total of 780 pT4 stage gastric cancer patients classified according to the 7th American Joint Committee on Cancer (AJCC) staging system were reviewed. Clinicopathologic features were compared between patients with narrow serosal changes (nSE), wide serosal changes (wSE) and invasions of adjacent structures (SI). Prognostic factors were evaluated by univariate and multivariate analyses. The 7th AJCC and novel pT4 subclassification were compared for prognostic performance using the linear trend chi-square test, likelihood ratio chi-square test, and Akaike information criterion (AIC) in the Cox regression analysis. RESULTS: The appropriate serosa infiltrate cutoff value was 8 cm. Most of the evaluated clinicopathologic features significantly differed between nSE and SI cancers. Only 3 factors were significantly different between wSE and SI cancers. The 5-year survival rates for patients with the novel pT4a and pT4b cancers were 47.2% and 14.52%, respectively, while they were 41.66% and 16.34% for the 7th AJCC pT4a and pT4b cancers, respectively. The novel pT4 subclassification had better discriminatory ability, monotonicity of gradients, and homogeneity and had smaller AIC values compared with the 7th AJCC pT4. CONCLUSIONS: It is reasonable to subclassify pT4 to pT4a (nSE) and pT4b (wSE/SI) because the novel pT4 subclassification had more potential to identify the different prognoses for patients with gastric cancer.

Stage-stratified analysis of prognostic significance of tumor size in patients with gastric cancer.

BACKGROUND: The prognostic significance of tumor size in gastric cancer is not well defined. The objective of this study was to identify the prognostic value of tumor size in patients with gastric cancer. METHODS: We retrospectively reviewed a total of 1800 patients with gastric cancer admitted to our hospital between 1997 and 2007. These patients were divided into two groups according to tumor size: small size group (SSG, tumor ≤5 cm) and large size group (LSG, tumor >5 cm). We compared clinico-pathologic features of the two groups and investigated the prognostic factors by performing univariate, multivariate, and stage- stratified analyses according to tumor size. RESULTS: LSG had more aggressive clinico-pathologic features than SSG. Tumor size was an independent prognostic indicator in patients with gastric cancer. In a stratified-pT, pN, and pTNM analysis, survival of patients with LSG was significantly worse than that of patients with SSG and advanced stage. Tumor size was not a significant predictor of survival in patients with early stage tumors. Large tumor size was associated with shorter survival in patients with stages N0, N1, N2, and N3, and stages I, II, III, and IV. CONCLUSIONS: Tumor size is a simple and practical prognostic factor in patients with gastric cancer. Tumor size could supplement clinical staging in the future.