High-Performance Blue Perovskite Light-Emitting Diodes Enabled by Synergistic Effect of Additives.

While quasi-two-dimensional (quasi-2D) perovskites have good properties of cascade energy transfer, high exciton binding energy, and high quantum efficiency, which will benefit high-efficiency blue PeLEDs, inefficient domain distribution management and unbalanced carrier transport impede device performance improvement. Herein, (2-(9H-carbazol-9-yl)ethyl)phosphonic acid (2PACz) and methyl 2-aminopyridine-4-carboxylate (MAC) were simultaneously introduced to a blue quasi-2D perovskite film. Relying on the synergistic effect of 2PACz and MAC, it not only modulates the phase distribution inhibiting the n = 2 phase but also greatly improves the electrical property of the quasi-2D perovskite film. As a result, the as-modified blue quasi-2D PeLED demonstrated an external quantum efficiency (EQE) of 17.08% and a luminance of 10142 cd m-2. This study exemplifies the synergistic effect among dual additives and offers a new effective additive strategy modulating phase distribution and building balanced carrier transport, which paves the way for the fabrication of highly efficient blue PeLEDs.

SNHG15-mediated feedback loop interplays with HNRNPA1/SLC7A11/GPX4 pathway to promote gastric cancer progression.

Dysregulation of long noncoding RNA (lncRNA) expression plays a pivotal role in the initiation and progression of gastric cancer (GC). However, the regulation of lncRNA SNHG15 in GC has not been well studied. Mechanisms for ferroptosis by SNHG15 have not been revealed. Here, we aimed to explore SNHG15-mediated biological functions and underlying molecular mechanisms in GC. The novel SNHG15 was identified by analyzing RNA-sequencing (RNA-seq) data of GC tissues from our cohort and TCGA dataset, and further validated by qRT-PCR in GC cells and tissues. Gain- and loss-of-function assays were performed to examine the role of SNHG15 on GC both in vitro and in vivo. SNHG15 was highly expressed in GC. The enhanced SNHG15 was positively correlated with malignant stage and poor prognosis in GC patients. Gain- and loss-of-function studies showed that SNHG15 was required to affect GC cell growth, migration and invasion both in vitro and in vivo. Mechanistically, the oncogenic transcription factors E2F1 and MYC could bind to the SNHG15 promoter and enhance its expression. Meanwhile, SNHG15 increased E2F1 and MYC mRNA expression by sponging miR-24-3p. Notably, SNHG15 could also enhance the stability of SLC7A11 in the cytoplasm by competitively binding HNRNPA1. In addition, SNHG15 inhibited ferroptosis through an HNRNPA1-dependent regulation of SLC7A11/GPX4 axis. Our results support a novel model in which E2F1- and MYC-activated SNHG15 regulates ferroptosis via an HNRNPA1-dependent modulation of the SLC7A11/GPX4 axis, which serves as the critical effectors in GC progression, and provides a new therapeutic direction in the treatment of GC.

Amphipathic Astaxanthin Additive for Low Voltage-loss Perovskite Solar Cells With Enhanced Quasi-Fermi Level Splitting and Solar Hydrogen Production Application.

Even though the power conversion efficiency (PCE) of perovskite solar cells (PSCs) is nearly approaching the Schottky-Queisser limit, low open-circuit voltage (Voc) and severe Voc loss problems continue to impede the improvement of PCEs. Astaxanthin (ASTA) additive is introduced in the formamidinium lead triiodide (FAPbI3) perovskite film as an additive, which can facilitate the transportation of charge carriers and interact with Pb2+ by its distinctive groupings. Furthermore, the addition of ASTA decreases the defect's active energy, regulates the deep-level defect by filling up the grain boundaries (GBs), and promotes the crystallization of perovskite film. Remarkably, an enhanced quasi-Fermi level splitting (QFLS) of 1.164 eV and a reduced Voc loss of only 96 mV are realized. The champion PCE of 24.56% is attained by ASTA-modified PSCs on the basis of 22.75% PCE. Moreover, the PSCs that underwent ASTA modification demonstrate improved operational stability, ensuring consistent output in real-world scenarios. Furthermore, PSCs with an active area of 1 cm2 are used for water electrolysis to produce hydrogen and exhibit a PCE of 22.41%. This work offers an environmentally benign solution to address the inherent issues of FAPbI3 PSCs and lays the groundwork for the development of a prospective solar hydrogen production application.

Zeolites as a Class of Semiconductors for High-Performance Electrically Transduced Sensing.

Zeolites are widely used as catalysts and adsorbents in the chemical industry, but their potential for electronic devices has been stunted to date, as they are commonly recognized as electronic insulators. Here, we have for the first time demonstrated that Na-type ZSM-5 zeolites are ultrawide-direct-band-gap semiconductors based on optical spectroscopy, variable-temperature current-voltage characteristics, and photoelectric effect as well as electronic structure theoretical calculations and further unraveled the band-like charge transport mechanism in electrically conductive zeolites. The increase in charge-compensating Na+ cations in Na-ZSM-5 decreases the band gap and affects its density of states, shifting the Fermi level close to the conduction band. Remarkably, the semiconducting Na-ZSM-5 zeolites have been first applied for constructing electrically transduced sensors that can sense trace-level (77 ppb) ammonia with unprecedentedly high sensitivity, negligible cross-sensitivity, and high stability under moisture ambient conditions compared with conventional semiconducting materials and conductive metal-organic frameworks (MOFs). The charge density difference shows that the massive electron transfer between NH3 molecules and Na+ cations ascribed to Lewis acid sites enables electrically transduced chemical sensing. This work opens a new era of zeolites in applications of sensing, optics, and electronics.

Synergistic Regulation Effect of Nitrate and Calcium Ions for Highly Luminescent and Robust α-CsPbI3 Perovskite.

The α-CsPbI3 nanocrystals (NCs) easily transform into yellow non-perovskite, accompanying with declining photoelectric properties that restricting their practical applications in diverse fields. Herein, the highly luminescent and robust α-CsPbI3 NCs is achieved through engineering the lattice symmetry of perovskite, enabled by the synergistic effect of NO3- ion passivation and Ca2+ ion doping. The introduced NO3- ions enhance the phase-change energy barrier and the surface steric hindrance, thus promoting the formation of α-CsPbI3 NCs with hyper-symmetric crystal structure, while the Ca2+ ion doping contributes to improving their lattice symmetry by significant regulation of the tolerance factor. As a result, the obtained α-CsPbI3 NCs display an outstanding photoluminescence quantum yield of 96.6%, together with the reduced defect state density and eminent conductivity. Most importantly, the as-engineered α-CsPbI3 NCs exhibit excellent stability under ambient conditions for 9 months and UV illumination for 32 h. It displays brilliant thermal stability, maintaining luminous intensity for 15 min under 140 °C, and performing desired durability and reversibility, evidenced by 160 °C cyclic test and 120 °C reversibility test. Given enhanced robustness, the as-engineered α-CsPbI3 NCs based light-emitting-diode devices are constructed, exhibiting a power efficiency of 105.3 lm W-1 and the excellent working stability for 18 h.

Tunable concentration-dependent upconversion and downconversion luminescence in NaYF4: Yb3+, Er3+@ NaYF4: Yb3+, Nd3+ core-shell nanocrystals for a dual-mode anti-counterfeiting imaging application.

Lanthanide-doped luminescent nanocrystals display both upconversion luminescence (UCL) and downconversion luminescence (DCL) properties, which offer potential applications in the second near-infrared window (NIR-II) images and biology sensors. Both UCL and DCL are sensitive to concentrations of activators. However, few works reveal the mechanism of concentration-dependent UCL and DCL. Herein, we synthesize core-shell upconversion nanocrystals (UCNCs) NaYF4: Yb3+(20%), Er3+ (2%)@NaYF4: Yb3+ (x%), Nd3+ (y%) with varying concentration of Nd and Yb ions. The UCL and DCL spectra are recorded under excitation of 980 nm and 808 nm lasers. The results indicate that the luminescence of core-shell UCNCs is influenced by the non-radiative rate between activators (Yb3+ and Nd3+) and the back energy transfer rate from Er3+ ions to activators. UCL tends to be obtained at a relatively low concentration of Yb3+ and Nd3+ ions (about 5%), whereas NIR emission tends to be obtained at a relatively high concentration of Yb3+ and Nd3+ ions (not higher than 20%). Dual-mode anti-counterfeiting imaging is successfully fabricated using core-shell UCNCs, which can be detected and distinguished by visible and infrared detectors. The visible versus infrared brightness of dual-mode anti-counterfeiting imaging can be tuned by varying the concentration of activators (Yb3+, Nd3+). Our work demonstrates concentration-dependent UCL and DCL in core-shell UCNCs, which provides reference to obtain NIR emission in the NIR-II region and adds encrypted dimensions for anti-counterfeiting patterns in the field of file encryption.

Pressure-Driven Abnormal Emission Blue-Shift of Lead-Free Halide Double Perovskite Cs2AgInCl6 Nanocrystals.

Lead-free halide double perovskites (DPs) have been proposed as stable and promising alternatives to lead halide perovskites. Understanding the structural-optical properties of halide DPs is important for their applications. In this study, Cs2AgInCl6 DP nanocrystals, with a direct band gap, were synthesized and studied. Because of a strong electron-phonon coupling leading to exciton self-trapping, a broad emission with a large Stokes shift of Cs2AgInCl6 DP nanocrystals is observed. We observed an abnormal blue-shifted emission accompanied by a red-shifted direct absorption edge because of the reduced electron-phonon coupling under compression in the cubic phase Cs2AgInCl6 DP nanocrystals. Our study clarified the basic structural-optical correlation of halide DPs and may promote their application in related fields.

The relationship between Lipocalin-2 level and hepatic steatosis in obese patients with NAFLD after bariatric surgery.

BACKGROUND: Lipocalin-2 (LCN2) has a critical effect on obesity as well as its associated comorbidities. The present study focused on analyzing serum LCN2 levels of obese patients with nonalcoholic fatty liver disease (NAFLD) and on determining relationship of hepatic steatosis improvement with LCN2 levels after laparoscopic sleeve gastrectomy (LSG). METHODS: This work enrolled ninety patients with obesity and NAFLD. Twenty-three of them underwent LSG. Anthropometric and biochemical parameters and serum LCN2 levels were determined at baseline and those at 6-month post-LSG. Controlled attenuation parameter (CAP) measured by FibroScan was adopted for evaluating hepatic steatosis. RESULTS: Among severe obesity patients, serum LCN2 levels were significantly increased (111.59 ± 51.16 ng/mL vs. 92.68 ± 32.68 ng/mL, P = 0.035). The CAP value was higher indicating higher liver fat content (360.51 ± 45.14 dB/m vs. 340.78 ± 45.02 dB/m, P = 0.044). With regard to surgical patients, liver function, glucose, and lipid levels were significantly improved after surgery. Serum LCN2 levels significantly decreased (119.74 ± 36.15 ng/mL vs. 87.38 ± 51.65 ng/mL, P = 0.001). Decreased CAP indicated a significant decrease in liver fat content (358.48 ± 46.13 dB/m vs. 260.83 ± 69.64 dB/m, P < 0.001). The decrease in LCN2 levels was significantly related to the reduced hepatic fat content and improvement in steatosis grade after adjusting for gender, age, and BMI decrease. CONCLUSIONS: Serum LCN2 levels are related to obesity and NAFLD. The decreased serum LCN2 levels could be an indicator of hepatic steatosis improvement.

Multi-wavelength pumped upconversion enhancement induced by Cu2-xS plasmonic nanoparticles in NaYF4@Cu2-xS core-shell structure.

Cu2-xS nanoparticles (NPs) demonstrate unique tunable localized surface plasmon resonance (LSPR) and nonlinear optical properties, which are promising materials for photoelectric and display devices. In this work, we present highly improved upconversion luminescence (UCL) in the NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+@Cu2-xS core-shell structure. The UCL enhancement is systemically studied under excitation of multi-wavelengths 808, 980, and 1540 nm, due to the broadband nature of Cu2-xS LSPR. Two different mechanisms synergistically contribute to the UCL enhancement, namely, the LSPR effect and two-photon effect, which lead to the extraordinary power dependence of UCL. UCL enhancement as high as 12-fold is achieved in the core-shell upconversion NPs (UCNPs). The core-shell NPs are printed on a paper substrate using a nano-printing technique, displaying different colors irradiated by different near-infrared light, and have potential applications in anti-counterfeiting, encryption, and display fields. These findings provide a method to design and optimize luminescent materials and demonstrate potential applications of plasmonic semiconductors and UCNPs.

Anatomical characteristics and classifications of gastrocolic trunk of Henle in laparoscopic right colectomy: preliminary results of multicenter observational study.

BACKGROUND: As a key landmark during laparoscopic right colectomy, the classification and variation of the gastrocolic trunk of Henle (GTH) remains to be clarified. The aim of this nationwide multicenter study was to describe the characteristics of the GTH intra-operatively during laparoscopic right colectomies. METHODS: Three hundred seventy-one patients who underwent laparoscopic right colectomies from January 2018 to March 2019 in 25 hospitals across China were enrolled in the study. The length of the GTH, the classification with a precise description of confluent tributaries, and other variations were analyzed. RESULTS: Of the 371 patients, 363 had a GTH. The proportion of type-0, type-I, type-II, and type-III was 15.2% (n = 55), 54.8% (n = 199), 25.3% (n = 92), and 4.7% (n = 17), respectively. The average length of the GTH was 8.5 mm, ranging from 2 to 30 mm. CONCLUSIONS: This is the first multicenter study with a large sample by which the GTH was classified based on laparoscopic intraoperative observation. Variations in the GTH were classified into four types based on the number of colic drainage veins (right colic, superior right colic, middle colic, accessory middle colic, and ileocolic veins), among which the right colic vein was the most common. The length of the GTH was relatively short, and thus might carry a risk of bleeding. Further clinical data should be correlated with the characteristics of the GTH.

Impact of Host Composition, Codoping, or Tridoping on Quantum-Cutting Emission of Ytterbium in Halide Perovskite Quantum Dots and Solar Cell Applications.

Recently, various lanthanide ions (Ln3+) have been successfully doped into perovskite quantum dots (PQDs), and the quantum-cutting emission of 2F5/2-2F7/2 for Yb3+with a measurable inner efficiency of more than 100% has been discovered and applied as the luminescent converter of solar cells, which has opened a new branch for the application of PQDs. In this work, to further improve the quantum-cutting efficiency of Yb3+, the codoping and tridoping methods were used to improve the quantum-cutting emission of PQDs. The Yb3+-Ln3+ (Ln = Nd, Dy, Tb, Pr, Ce) pair-doped CsPbClxBryI3-x-y PQDs were fabricated, with all displaying excitonic emission, narrow-band emission of Ln3+ ions, and quantum-cutting emission of Yb3+ ions. It was interesting that Yb3+-Pr3+ as well as Yb3+-Ce3+ pairs could effectively sensitize the emission of Yb3+, owing to Pr3+ and Ce3+ ions offering intermediate energy states close to the exciton transition energy of the PQDs. After host composition optimization and tridoping investigation, overall emissions with a 173% photoluminescence quantum yield (PLQY) were obtained in the Yb3+-Pr3+-Ce3+-tridoped CsPbClBr2 PQDs. Then, the tridoped PQDs were designed as the down-converter for CuIn1-xGaxSe2 (CIGS) as well as the silicon solar cells, which leads to an enhancement of the power conversion efficiency (PCE) of as high as ∼20%. The modified CIGS was further employed to charge the smart mobile phone, which could largely shorten the charging time from 180 to 150 min. This finding is of great significant for expanding the application fields of the impurity-doped PQDs.

Effects of CO2 pneumoperitoneum on proliferation, apoptosis, and migration of gastrointestinal stromal tumor cells.

BACKGROUND: The purpose of the study was to investigate the proliferation and migration capability of human gastrointestinal stromal tumor line GIST-T1 after exposure to different pressures and times of CO2 pneumoperitoneum. METHODS: We established simulated CO2 pneumoperitoneum environment in vitro and divided the human GIST cell GIST-T1 into open control group, 8 mmHg CO2 pneumoperitoneum treatment group and 15 mmHg CO2 pneumoperitoneum treatment group. Each group was divided into two subgroups respectively cultured for 1 h and 3 h. pH value of cell culture, cell growth curve, and cell cycle distribution of each group was measured. By application of scratch healing tests and Transwell chamber experiments, mobility ratio and number of cells through 8 µm membranes were measured to assess the migration ability of cells in each group after intervention. RESULTS: Cell culture pH value of each subgroup in CO2 group decreased significantly after exposed in CO2 pneumoperitoneum (P < 0.01). The proliferation of GIST-T1 cells in 15 mmHg CO2 group was significantly inhibited early (1-2 days) (P < 0.05) and the proliferation of GIST-T1 cells in 8 mmHg CO2 1 h subgroup and 15 mmHg CO2 1 h subgroup was increased significantly late (4-6 days) (P < 0.05) after the interventions of CO2 pneumoperitoneum. The percentage of cells in G0-G1 phase increased, the percentage of S phase cells decreased (P < 0.01) in 1-h subgroup and 3-h subgroup of 15 mmHg CO2 group 24 h after exposure to CO2. The percentage of cells in S phase increased in 1-h subgroup of 8 mmHg CO2 group and decreased in 3-h subgroup of 15 mmHg CO2 group 72 h after exposure to CO2. In the Transwell chamber experiment, the cell number through 8-µm membrane increased significantly (P < 0.01) in 3-h subgroup of CO2 group compared to that in 3-h subgroup of control group. CONCLUSIONS: The routine pressure and duration of CO2 pneumoperitoneum used in clinic did not promote the proliferation of gastrointestinal stromal tumors, but had a potential risk of increasing postoperative recurrence and distant metastasis.

Long Noncoding RNA BCYRN1 Promotes the Proliferation of Colorectal Cancer Cells via Up-Regulating NPR3 Expression.

BACKGROUND/AIMS: Long noncoding RNAs (lncRNAs) constitute a large proportion of noncoding transcripts that have recently emerged as a new class of important regulators in cancers. LncRNA BCYRN1, also known as BC200, has a potential function in tumorigenesis. However, the clinical significance of BCYRN1 and its effect on colorectal cancer (CRC) progression remains unclear. METHODS: Quantitative reverse transcriptase PCR (qRT-PCR) was performed to investigate the expression of BCYRN1 in CRC tissues and cell lines. The biological function of BCYRN1 was also investigated through knockdown and overexpression of BCYRN1 in vitro. Microarray bioinformatics analysis was performed to analyze the putative targets of BCYRN1. RESULTS: The results showed that BCYRN1 expression was significantly upregulated in 96 CRC tumor tissues compared with para-carcinoma control tissues. Additionally, BCYRN1 overexpression was associated with larger tumor size and advanced pathological stages in CRC patients. In vitro BCYRN1 knockdown significantly inhibited the proliferation and apoptosis of CRC cells. Furthermore, NPR3 was identified to be a target of BCYRN1 and was downregulated by BCYRN1 knockdown. CONCLUSION: Together, we provide the first evidence that BCYRN1 plays an oncogenic role in CRC cells. BCYRN1 may be a promising prognostic biomarker and a potential therapeutic target for CRC.

Highly stable and water-soluble monodisperse CsPbX3/SiO2 nanocomposites for white-LED and cells imaging.

In spite of the excellent optical properties of all-inorganic halide perovskite quantum dots (PQDs), they still suffer from inherent poor stability even when exposed to moisture from the atmosphere, restricting their applications, especially in white-light-emitting diodes (LEDs) and cells imaging. Here, we proposed a strategy by encapsulating the CsPbX3 (X = Cl, Br, I) PQDs into silica nanoplates to prepare highly stable and water-soluble CsPbX3/SiO2 nanocomposites. First, the 120 nm monodisperse CsPbX3/SiO2 nanocomposites inlayed with several CsPbX3 PQDs were fabricated via the modified Stöber method. After coating, their stability exposed in the air was largely improved for all the CsPbX3 (X = Cl, Br, I) PQDs without changing their emission peaks and full-width at half-maximum, attributed to the suppression of the anion-exchange and decomposition. Moreover, further experiments demonstrated that the CsPbX3/SiO2 nanocomposites were highly water-soluble and stable in the water. Their applications in LEDs and cell imaging demonstrated their ultrastability and high biocompatibility. Therefore, this study shows the possibility of their use in photoelectric devices and biological applications.

Doping Lanthanide into Perovskite Nanocrystals: Highly Improved and Expanded Optical Properties.

Cesium lead halide (CsPbX3) perovskite nanocrystals (NCs) have demonstrated extremely excellent optical properties and great application potentials in various optoelectronic devices. However, because of the anion exchange, it is difficult to achieve white-light and multicolor emission for practical applications. Herein, we present the successful doping of various lanthanide ions (Ce3+, Sm3+, Eu3+, Tb3+, Dy3+, Er3+, and Yb3+) into the lattices of CsPbCl3 perovskite NCs through a modified hot-injection method. For the lanthanide ions doped perovskite NCs, high photoluminescence quantum yield (QY) and stable and widely tunable multicolor emissions spanning from visible to near-infrared (NIR) regions are successfully obtained. This work indicates that the doped perovskite NCs will inherit most of the unique optical properties of lanthanide ions and deliver them to the perovskite NC host, thus endowing the family of perovskite materials with excellent optical, electric, or magnetic properties.

Effect of surgery-induced acute muscle wasting on postoperative outcomes and quality of life.

BACKGROUND: Gastrectomy results in a significant loss of body composition in the long term, but the acute skeletal muscle wasting after gastrectomy has been rarely investigated. Moreover, the association between postoperative muscle wasting and quality of life (QOL) has never been reported. In the present study, we aimed to investigate the risk factors for acute muscle wasting after gastric cancer surgery and its effect on QOL and short-term postoperative outcomes. METHODS: We conducted a prospective study of patients who underwent curative gastrectomy for gastric cancer between June 2015 and December 2015. Skeletal muscle mass was measured by computed tomography within 1 month before and 1 week after surgery. QOL was assessed 1, 3, and 6 months postoperatively. Univariate and multivariate analyses were performed to identify the risk factors for clinically relevant muscle wasting (muscle wasting ≥10%). RESULTS: A total of 110 patients were included, in which 35 patients had muscle wasting ≥10% within 1 week after surgery. Age ≥65 years and diabetes were independent risk factors for muscle wasting ≥10%. Patients with muscle wasting ≥10% had a poorer QOL in terms of fatigue and physical functioning at 1 and 3 months postoperatively, as well as a higher incidence of postoperative complications, a higher incidence of handgrip strength reduction ≥10%, longer hospital stays, and higher costs. CONCLUSIONS: Age ≥65 years and diabetes were independently associated with clinically relevant muscle wasting within 1 week after gastric cancer surgery. Clinically relevant muscle wasting was associated with a poorer QOL and short-term outcomes after surgery.

Laparoscopic sleeve gastrectomy improves body composition and alleviates insulin resistance in obesity related acanthosis nigricans.

BACKGROUND: Acanthosis nigricans (AN) has a close relationship with obesity. It is believed that obesity and AN have the common pathophysiological basis such as hyperinsulinism. This study is aimed to observe the effect of laparoscopic sleeve gastrectomy (LSG) on body composition and insulin resistance in Chinese obese patients with acanthosis nigricans. METHODS: A total of 37 obese patients who underwent LSG in our hospital were selected for analysis. They were divided into simple obesity (OB n = 14) and obesity with acanthosis nigricans (AN n = 23) group respectively. Body composition was measured by dual-energy X-ray absorptiometry (DEXA). Anthropometric measurements and glucolipid metabolism before and 3 months post LSG were collected for analysis. RESULTS: Patients with AN got noticeable improvement in skin condition and their AN score was significantly decreased (3.52 ± 0.79 vs. 1.48 ± 0.73, P < 0.001).Alleviated insulin resistance and more trunk fat loss than limbs' were observed in both groups (P value < 0.01). In AN group, preoperative android fat mass (FM) was positively correlated with fasting insulin and natural logarithm of HOMA-IR (LNIR) (r = 0.622, 0.608, respectively; all P < 0.01). Besides, changes in android FM and visceral adipose tissue (VAT) also showed significantly positive correlation with changes in LNIR (r = 0.588, r = 0.598, respectively; all P < 0.01). CONCLUSIONS: LSG had a positive impact on body composition and skin condition in Chinese obese patients with AN. Loss of android FM and VAT might result in the alleviation of insulin resistance in AN patients. Android fat distribution seems to be a potential indicator of postoperative metabolic benefits for obese patients with AN.

Laparoscopy-assisted versus open distal gastrectomy for gastric cancer in elderly patients: a retrospective comparative study.

BACKGROUND: With the current increased longevity in elderly population, surgeons can expect to operate more frequently on elderly patients with both malignancies and comorbid medical conditions. This study aimed to compare the surgical and early postoperative outcomes of laparoscopy-assisted distal gastrectomy (LADG) with those of open distal gastrectomy (ODG) for gastric cancer in patients 70 years of age or older. METHODS: Retrospective analysis based on a prospectively collected database of elderly patients who underwent laparoscopy-assisted distal gastrectomy or ODG from February 2013 to January 2014. Preoperative patient baseline parameters, surgical and oncological outcomes, postoperative complications and pathologic results were analyzed in this report. RESULTS: Distal gastrectomy was performed for 50 patients with the age of 70 years or older, using laparoscopic surgery for 23 patients (LADG group) and open surgery for 27 patients (ODG group). The mean age of LADG group was 76.6 years and ODG group 80.0 years. The comparison between the two groups revealed statistically similar results regarding age, gender, BMI, ASA class, history of previous surgeries, CCI and pathologic characteristics. The LADG group was characterized by less intraoperative blood loss (LADG group 100 mL vs. ODG group 250 mL, P < 0.001), less narcotic use (LADG group 1 day vs. ODG group 3 days, P < 0.001), faster bowel function recovery (time to first flatus: LADG group 51.6 h vs. ODG group 67.2 h, P < 0.001; days to oral intake: LADG group 6.1 days vs. ODG group 7.9 days, P = 0.002) and shorter postoperative hospital stay (LADG group 12 days vs. ODG group 16 days, P < 0.001). There was no significant difference in postoperative complication rate (overall complication rate: LADG group 21.7 % vs. ODG group 25.9 %, P = 0.730), survival rate (P = 0.719), postoperative recurrence and metastasis rate between the patients who underwent LADG and ODG. CONCLUSIONS: LADG for gastric cancer is feasible, efficacious and safe in elderly patients and may be superior to conventional open resection as regards some surgical outcomes.

Modulation of upconversion white light emission in PMMA/NaYF(4):Yb(3+), Er(3+), Tm(3+) composite photonic crystals.

In recent years, spontaneous emission modulation of emitters in photonic crystals (PCs) has been widely reported. However, the modulation of PCs on upconversion (UC) white light emission has been rarely studied. In this Letter, triply doped PMMA/NaYF(4):Yb(3+), Er(3+), Tm(3+) composite photonic crystals were successfully fabricated and white light emission was obtained. It is interesting to observe that the chromaticity could be conveniently tuned by changing the photonic stop band (PSB), the incident angle, or the power of the excitation light.