Is chemotherapy beneficial? A retrospective study of chemotherapy in patients with invasive intraductal papillary-mucinous carcinoma.

Background and aim: Whether chemotherapy can improve the prognosis of invasive intraductal papillary-mucinous carcinoma (IPMC) still remains unclear. The aim of this study is to observe the difference in survival time of patients with invasive IPMC receiving or not receiving chemotherapy. Methods: 117 patients with invasive IPMC were included in The Surveillance, Epidemiology, and End Results (SEER) database. These patients were subsequently divided into two subgroups according to whether they received chemotherapy or not: the non-chemotherapy group (patients who did not receivechemotherapy, N = 58), the chemotherapy group (patients who received chemotherapy, N = 59). The overall survival (OS) and cancer specific survival (CSS) of two treatment groups were evaluated. Results: Before adjusting for pathology grade, the Kaplan-Meier analysis showed that the difference of survival time is not significant between non-chemotherapy group and chemotherapy group (P > 0.05), but the land-mark analysis showed that short-term death risk of the chemotherapy group is significantly lower than non-chemotherapy group (P < 0.05). After adjust the pathology grade, survival time of the chemotherapy group is significantly longer than non-chemotherapy group (P < 0.05). Univariate and multivariate Cox regression showed that chemotherapy was an independent prognostic protective factor for invasive IPMC (P < 0.05). Land-mark analysis showed that short-term death risk of the chemotherapy group is significantly lower than non-chemotherapy group in N1-N2 subgroup (P < 0.05). Conclusion: Chemotherapy is an independent protective factor IPMC, especially reducing the risk of short-term death for IPMC patients with lymph node metastasis.

Association between plain ropivacaine dose and spinal hypotension for cesarean delivery: a retrospective study.

Background: Data on the association between the plain ropivacaine dose and maternal hypotension during cesarean delivery are limited. Thus, this study aimed to explore this association. Methods: This retrospective study included patients undergoing cesarean sections under spinal or combined spinal-epidural anesthesia with plain ropivacaine at The First Hospital of Fuyang, Hangzhou, China, between 2018 and 2022. Data were obtained from the anesthesia information management system. Liner trend tests were used to distinguish the linear relationship between spinal hypotension and the plain ropivacaine dose, and receiver operating characteristic curves were used to calculate the dose threshold. Logistic regression was used to adjust for confounders. Sensitivity analyses were performed to evaluate the stability of the results. The secondary outcome was vasopressor use (metaraminol and ephedrine). Results: In total, 1,219 women were included. The incidence of hypotension linearly correlated with the plain ropivacaine dose (adjusted P-value for trend, P < 0.001). Thus, we used a dose threshold of 17.5 mg to compare the dose as a binary variable (≥17.5 mg vs. < 17.5 mg). Plain ropivacaine doses of ≥17.5 mg were associated with a higher incidence of spinal hypotension (adjusted odds ratio: 2.71; 95% confidence interval [1.85-3.95]; P < 0.001). The sensitivity analyses yielded similar results. The plain ropivacaine dose also correlated with metaraminol use but not ephedrine use. Conclusions: The incidence of spinal-induced hypotension in women undergoing cesarean section linearly correlated with the plain ropivacaine dose. The dose threshold for hypotension risk was 17.5 mg.

Combining single-cell and bulk RNA sequencing, NK cell marker genes reveal a prognostic and immune status in pancreatic ductal adenocarcinoma.

The NK cell is an important component of the tumor microenvironment of pancreatic ductal adenocarcinoma (PDAC), also plays a significant role in PDAC development. This study aimed to explore the relationship between NK cell marker genes and prognosis, immune response of PDAC patients. By scRNA-seq data, we found the proportion of NK cells were significantly downregulated in PDAC and 373 NK cell marker genes were screened out. By TCGA database, we enrolled 7 NK cell marker genes to construct the signature for predicting prognosis in PDAC patients. Cox analysis identified the signature as an independent factor for pancreatic cancer. Subsequently, the predictive power of signature was validated by 6 GEO datasets and had an excellent evaluation. Our analysis of relationship between the signature and patients' immune status revealed that the signature has a strong correlation with immunocyte infiltration, inflammatory reaction, immune checkpoint inhibitors (ICIs) response. The NK cell marker genes are closely related to the prognosis and immune capacity of PDAC patients, and they have potential value as a therapeutic target.

Comparison of 95% effective dose of remimazolam besylate and propofol for gastroscopy sedation on older patients: A single-centre randomized controlled trial.

AIMS: Advanced age is an important risk factor for adverse events during procedural sedation. Remimazolam is safe and effective in gastroscopic sedation. However, the ideal dose and application for older patients are not well known. We aim to investigate its 95% effective dose (ED95) for older patients undergoing gastroscopy and to assess its safety and efficacy, with propofol as the comparison. METHODS: The trial consists of 2 parts, patients aged >65 years and scheduled for outpatient painless gastroscopy were enrolled. In the first part, Dixon's up-and-down methodology was used to determine the ED95 of remimazolam besylate and propofol for gastroscopic insertion, in combination with 0.2 µg/kg remifentanil. In the second part, patients in each group received 0.2 µg/kg remifentanil and ED95 dose of the study drugs for sedation induction, supplemental doses were added to maintain sedation depth when necessary. The primary outcome was the incidence of adverse events. The secondary outcome was the recovery time. RESULTS: The ED95 of remimazolam besylate and propofol induction were 0.2039 (95% confidence interval 0.1753-0.3896) mg/kg and 1.9733 (95% confidence interval 1.7346-3.7021) mg/kg respectively. Adverse events were reported in 26 (40.6%) patients in the remimazolam group and 54 (83.1%) in the propofol group (P < .0001), whereas the remimazolam group presented a higher incidence of hiccups (P = .0169). Besides, the median time to awakening was approximately 1 min shorter with remimazolam than with propofol (P < .05). CONCLUSION: For older patients undergoing gastroscopy, the ED95 dose of remimazolam is a safer alternative than propofol when inducing the same sedation depth.

Risk factors and outcomes of intraoperative hypothermia in neonatal and infant patients undergoing general anesthesia and surgery.

Objective: The incidence of intraoperative hypothermia remains high in pediatric patients during anesthesia and surgery even though core body temperature monitoring and warming systems have been greatly improved in recent years. We analyzed the risk factors and outcomes of intraoperative hypothermia in neonates and infants undergoing general anesthesia and surgery. Methods: The data on the incidence of intraoperative hypothermia, other clinical characteristics, and outcomes from electronic records of 1,091 patients (501 neonates and 590 infants between 28 days and 1 year old), who received general anesthesia and surgery, were harvested and analyzed. Intraoperative hypothermia was defined as a core temperature below 36°C during surgery. Results: The incidence of intraoperative hypothermia in neonates was 82.83%, which was extremely higher than in infants (38.31%, p < 0.001)-the same as the lowest body temperature (35.05 ± 0.69°C vs. 35.40 ± 0.68°C, p < 0.001) and the hypothermia duration (86.6 ± 44.5 min vs. 75.0 ± 52.4 min, p < 0.001). Intraoperative hypothermia was associated with prolonged PACU, ICU, hospital stay, postoperative bleeding, and transfusion in either age group. Intraoperative hypothermia in infants was also related to prolonged postoperative extubation time and surgical site infection. After univariate and multivariate analyses, the age (OR = 0.902, p < 0.001), weight (OR = 0.480, p = 0.013), prematurity (OR = 2.793, p = 0.036), surgery time of more than 60 min (OR = 3.743, p < 0.001), prewarming (OR = 0.081, p < 0.001), received >20 mL/kg fluid (OR = 2.938, p = 0.004), and emergency surgery (OR = 2.142, p = 0.019) were associated with hypothermia in neonates. Similar to neonates, age (OR = 0.991, p < 0.001), weight (OR = 0.783, p = 0.019), surgery time >60 min (OR = 2.140, p = 0.017), pre-warming (OR = 0.017, p < 0.001), and receive >20 mL/kg fluid (OR = 3.074, p = 0.001) were relevant factors to intraoperative hypothermia in infants along with the ASA grade (OR = 4.135, p < 0.001). Conclusion: The incidence of intraoperative hypothermia was still high, especially in neonates, with a few detrimental complications. Neonates and infants each have their different risk factors associated with intraoperative hypothermia, but younger age, lower weight, longer surgery time, received more fluid, and no prewarming management were the common risk factors.

Inadvertent perioperative hypothermia and surgical site infections after liver resection.

BACKGROUND: In the overall surgical population, inadvertent perioperative hypothermia has been associated with an increased incidence of surgical site infection (SSI). However, recent clinical trials did not validate this notion. This study aimed to investigate the potential correlation between inadvertent perioperative hypothermia and SSIs following liver resection. METHODS: This retrospective cohort study included all consecutive patients who underwent liver resection between January 2019 and December 2021 at the First Affiliated Hospital, Zhejiang University School of Medicine. Perioperative temperature managements were implemented for all patients included in the analysis. Estimated propensity score matching (PSM) was performed to reduce the baseline imbalances between the normothermia and hypothermia groups. Before and after PSM, univariate analyses were performed to evaluate the correlation between hypothermia and SSI. Multivariate regression analysis was performed to determine whether hypothermia was an independent risk factor for postoperative transfusion and major complications. Subgroup analyses were performed for diabetes mellitus, age > 65 years, and major liver resection. RESULTS: Among 4000 patients, 2206 had hypothermia (55.2%), of which 150 developed SSI (6.8%). PSM yielded 1434 individuals in each group. After PSM, the hypothermia and normothermia groups demonstrated similar incidence rates of SSI (6.3% vs. 7.0%, P = 0.453), postoperative transfusion (13.3% vs. 13.7%, P = 0.743), and major complications (9.0% vs. 10.1%, P = 0.309). Univariate regression analysis revealed no significant effects of hypothermia on the incidence of SSI in the group with the highest hypothermia exposure [odds ratio (OR) = 1.25, 95% confidence interval (CI): 0.84-1.87, P = 0.266], the group with moderate exposure (OR = 1.00, 95% CI: 0.65-1.53, P = 0.999), or the group with the lowest exposure (OR = 1.11, 95% CI: 0.73-1.65, P = 0.628). The subgroup analysis revealed similar results. Regarding liver function, patients in the hypothermia group demonstrated lower γ-glutamyl transpeptidase (37 vs. 43 U/L, P = 0.001) and alkaline phosphatase (69 vs. 72 U/L, P = 0.016). However, patients in the hypothermia group exhibited prolonged activated partial thromboplastin time (29.2 vs. 28.6 s, P < 0.01). CONCLUSIONS: In our study of patients undergoing liver resection, we found no significant association between mild perioperative hypothermia and SSI. It might be due to the perioperative temperature managements, especially active warming measures, which limited the impact of perioperative hypothermia on the occurrence of SSI.

Establishment of Difficult Caudal Epidural Blockade Prediction Model.

Background: We aimed to develop a predictive difficult caudal epidural blockade (pDCEB) model when ultrasound was not available and verified the role of ultrasound in difficult caudal epidural blockade (CEB). Methods: From October 2018 to March 2019, this study consisted of three phases. First, we prospectively enrolled 202 patients scheduled to undergo caudal epidural anesthesia and assessed risk factors by binary logistic regression to develop the predictive scoring system. Second, we enrolled 87 patients to validate it. The receiver operating characteristic (ROC) curve was used to evaluate the performance of the prediction model. Youden-index was used to determine the cut-off value. Third, we enrolled 68 patients with a high risk of difficult CEB (pDCEB score ≥3) and randomized them into ultrasound and landmark groups to verify the role of ultrasound. Result: The rate of difficult CEB was 14.98% overall 289 patients. We found a correlation between unclear palpation of the sacral hiatus (OR 9.688) and cornua (OR 4.725), the number of the sacral hiatus by palpation ≥1 (OR 4.451), and history of difficult CEB (OR 39.282) with a higher possibility of difficult CEB. The area under the receiver operating characteristic curve of the pDCEB model involving the aforementioned factors was 0.889 (95% CI, 0.827-0.952) in the development cohort and 0.862 (95% CI, 0.747-0.977) in the validation cohort. For patients with a pDCEB score ≥3, a preprocedure ultrasound scan could reduce the incidence of difficult CEB (55.56% in the Landmark group vs. 9.38% in the ultrasound group, p < 0.001). Conclusion: This novel pDCEB score, which takes into account palpation of the sacral hiatus/cornua, number of the sacral hiatus by palpation ≥1, and history of difficult CEB, showed a good predictive ability of difficult CEB. The findings suggested that performing an ultrasound scan is essential for patients with a pDCEB score ≥3. Trial registration: No: ChiCTR1800018871, Site URL: https://www.chictr.org.cn/edit.aspx?pid=31875&htm=4; Principal investigator: Jialian Zhao, Date of registration: 2018.10.14.

Oxycodone is superior to morphine for pain relief following peroral oesophageal myotomy: a prospective, randomized, controlled trial.

Introduction: Patients underwent peroral endoscopic myotomy (POEM) for treating achalasia suffered with mild to moderate, sometimes even severe postoperative pain. Aim: To evaluate the efficacy of oxycodone on postoperative analgesia of patients undergoing PEOM. Material and methods: In this prospective, double-blinded, randomized, controlled trial, patients with achalasia were recruited and received 0.08 mg/kg oxycodone or morphine 15 min before the end of the POEM procedure. The short-form McGill questionnaire (SF-MPQ) was used to measure the postoperative pain at 0, 2, 6, 24, and 48 h after surgery, which included the visual analogue scale (VAS), the present pain intensity (PPI) scale, and the pain rating index (PRI). Results: A total of 73 patients were included, of whom 36 received oxycodone, and 37 received morphine. Compared with morphine, patients received oxycodone were associated with lower VAS in the first 24 h postoperatively (1.64 ±0.76 vs. 2.14 ±1.23, p = 0.042) as well as PPI at 2 h (1.11 ±0.40 vs. 2.22 ±0.89, p < 0.001), 6 h (1.42 ±0.55 vs. 2.08 ±0.92, p < 0.001) and 24 h (1.06 ±0.23 vs. 1.30 ±0.46, p = 0.006). Patients who received oxycodone experienced lower sensory McGill pain score than those who received morphine at 2, 6, 24, and 48 h after surgery (p < 0.05). Significantly lowered affective McGill pain score was observed in the oxycodone group at 0, 2, and 24 h postoperatively. Regarding the PRI, the sum of both sensory and affective McGill pain scores, patients with oxycodone therapy were associated with better scores postoperatively. Conclusions: Oxycodone appears to be superior to morphine in dealing with post-POEM pain, which has distinct visceral pain characteristics.

Polyethylene Oxide as a Multifunctional Binder for High-Performance Ternary Layered Cathodes.

Nickel cobalt manganese ternary cathode materials are some of the most promising cathode materials in lithium-ion batteries, due to their high specific capacity, low cost, etc. However, they do have a few disadvantages, such as an unstable cycle performance and a poor rate performance. In this work, polyethylene oxide (PEO) with high ionic conductance and flexibility was utilized as a multifunctional binder to improve the electrochemical performance of LiNi0.6Co0.2Mn0.2O2 cathode materials. Scanning electron microscopy showed that the addition of PEO can greatly improve the adhesion of the electrode components and simultaneously enhance the integrity of the electrode. Thus, the PEO-based electrode (20 wt% PEO in PEO/PVDF) shows a high electronic conductivity of 19.8 S/cm, which is around 15,000 times that of the pristine PVDF-based electrode. Moreover, the PEO-based electrode exhibits better cycling stability and rate performance, i.e., the capacity increases from 131.1 mAh/g to 147.3 mAh/g at 2 C with 20 wt% PEO addition. Electrochemical impedance measurements further indicate that the addition of the PEO binder can reduce the electrode resistance and protect the LiNi0.6Co0.2Mn0.2O2 cathode materials from the liquid electrolyte attack. This work offers a simple yet effective method to improve the cycling performance of the ternary cathode materials by adding an appropriate amount of PEO as a binder in the electrode fabrication process.

Graphene Quantum Dots Improved "Caterpillar"-like TiO2 for Highly Efficient Photocatalytic Hydrogen Production.

Photocatalytic water splitting for hydrogen production via heterojunction provides a convenient approach to solve the world crises of energy supply. Herein, graphene quantum dots modified TiO2 hybrids (TiO2-GQDs) with a "caterpillar"-like structure exhibit stronger light absorption in the visible region and an enhanced hydrogen production capacity of about 3.5-fold compared to the pristine TiO2 caterpillar. These results inferred that the addition of GQDs drastically promotes the interfacial electron transfer from GQDs to TiO2 through C-O-Ti bonds via the bonding between oxygen vacancy sites in TiO2 and in-plane oxygen functional groups in GQDs. Using a "caterpillar"-like structure are expected to provide a new platform for the development of highly efficient solar-driven water splitting systems based on nanocomposite photocatalyst.

Confocal laser endomicroscopy under propofol-based sedation for early gastric cancer and pre-cancerous lesions is associated with better diagnostic accuracy: a retrospective cohort study in China.

BACKGROUND: Confocal laser endomicroscopy (CLE) has advantages in detecting gastric neoplastic lesions, meanwhile it requires strict patient cooperation. Sedation could improve patient cooperation and quality of endoscopy. However, sedation is still not very popular in some resource-limited countries and regions. The purpose of this study was to compare propofol-based sedated versus un-sedated CLE in the value of diagnosing early gastric cancer (EGC) and precancerous lesions. METHODS: A retrospective, cohort, single center study of 226 patients who underwent CLE between January 1, 2015 and December 31, 2017 was performed. Patients enrolled were allocated into the propofol-based sedated group (n = 126) and the un-sedated group (n = 100). The comparison of validity and reliability of CLE for identifying EGC and precancerous lesions between the two groups was performed through analyzing CLE diagnosis and pathological diagnosis. Reporting followed the STROBE guidelines. RESULTS: The area under receiver operating characteristic curve (AUROC) of diagnosing EGC in the sedated group was 0.97 (95 % CI: 0.95 to 0.99), which was higher than that in the un-sedated group (0.88 (95 % CI: 0.80 to 0.97), P = 0.0407). CLE with sedation performed better than without sedation in diagnosing intraepithelial neoplasia and intestinal metaplasia (P = 0.0008 and P = 0.0001, respectively). For patients considered as high-grade intraepithelial neoplasia or EGC by endoscopists, they would not get biopsy during CLE but receive endoscopic submucosal dissection (ESD) subsequently, and the misdiagnosis rate of CLE was 0 % in the sedated group and 27.59 % (95 % CI: 10.30-44.91 %) in the un-sedated group (P = 0.006). CONCLUSIONS: Propofol based sedation was associated with improved diagnostic value of CLE for detecting EGC as well as precancerous lesions (intraepithelial neoplasia OR intestinal metaplasia).

Full-length sequencing of ginkgo transcriptomes for an in-depth understanding of flavonoid and terpenoid trilactone biosynthesis.

Ginkgo biloba L. is regarded as the most ancient living tree, and its kernel has been used as a traditional Chinese medicine for more than 2,000 years. The leaf extracts of this tree have been among the bestselling herbal remedies in Western countries since the last century. To understand the biosynthesis of the pharmacologically active ingredients in G. biloba, flavonoids and terpenoid trilactones (TTLs), we sequenced the transcriptomes of G. biloba leaves, kernels and testae with Iso-Seq and RNA-Seq technologies and obtained 152,524 clean consensus reads. When these reads were used to improve the annotation of the G. biloba genome, 4,856 novel genes, 25,583 new isoforms of previously annotated genes and 4,363 lncRNAs were discovered. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that genes involved in growth, regulation and response to stress were more likely to be regulated by alternative splicing (AS) or alternative polyadenylation (APA), which represent the two most important posttranscriptional regulation mechanisms. It was found that some of the characterized genes involved in the biosynthesis of flavonoids and TTLs were also possibly regulated by AS and APA. Using phylogenetic and gene expression pattern analyses, some candidate genes for the biosynthesis of flavonoids and TTLs were screened. After qRT-PCR validation, the final candidate genes for flavonoid biosynthesis included three UDP-glycosyltransferases and one MYB transcription factor, while the candidate genes for TTL biosynthesis included two cytochrome P450 and one WRKY transcription factor. Our study suggested that Iso-Seq may play an important role in improving genome annotation, elucidating AS and APA mechanisms and discovering candidate genes involved in the biosynthesis of some secondary metabolites.

Localized Electrons Enhanced Ion Transport for Ultrafast Electrochemical Energy Storage.

The rate-determining process for electrochemical energy storage is largely determined by ion transport occurring in the electrode materials. Apart from decreasing the distance of ion diffusion, the enhancement of ionic mobility is crucial for ion transport. Here, a localized electron enhanced ion transport mechanism to promote ion mobility for ultrafast energy storage is proposed. Theoretical calculations and analysis reveal that highly localized electrons can be induced by intrinsic defects, and the migration barrier of ions can be obviously reduced. Consistently, experiment results reveal that this mechanism leads to an enhancement of Li/Na ion diffusivity by two orders of magnitude. At high mass loading of 10 mg cm-2 and high rate of 10C, a reversible energy storage capacity up to 190 mAh g-1 is achieved, which is ten times greater than achievable by commercial crystals with comparable dimensions.

Improved Analgesic Effect of Paravertebral Blocks before and after Video-Assisted Thoracic Surgery: A Prospective, Double-Blinded, Randomized Controlled Trial.

Despite being less invasive, patients who underwent video-assisted thoracic surgery (VATS) suffered considerable postoperative pain. Paravertebral block (PVB) was proven to provide effective analgesia in patients with VATS; however, there is no difference in pain relief between preoperative PVB and postoperative PVB. This study was aimed to investigate the analgesic efficacy of combination of preoperative and postoperative PVB on the same patient undergoing VATS. In this prospective, double-blinded, randomized controlled trial, 44 patients undergoing VATS were enrolled, and they received patient-controlled intravenous analgesia (PCIA) with sufentanil plus preoperative PVB (Group A, n = 15) or postoperative PVB (Group B, n = 15), or combination of preoperative and postoperative PVB (Group C, n = 14). The primary outcome was sufentanil consumption and PCIA press times in the first 24 hours postoperatively. Also, data of postoperative use of PCIA and visual analogue scale (VAS) were collected. In the first 24 hours postoperatively, median sufentanil consumption in Group C was 0 (0-34.75) µg, which was much less than that in Group A (45.00 (33.00-47.00) µg, p=0.005) and Group B (36 (20.00-50.00) µg, p=0.023). Patients in Group C pressed less times of PCIA (0 (0-0) times) than patients in Group A (2 (1-6) times, p < 0.001) and Group B (2 (1-3) times, p=0.009). Kaplan-Meier analysis showed patients with combination of preoperative and postoperative PVB had a higher PCIA-free rate than patients with either technique alone (p=0.003). The VAS among the three groups was comparable postoperatively. The combination of both preoperative and postoperative PVB provides better analgesic efficacy during the early postoperative period and may be an alternative option for pain control after VATS. This trial is registered with ChiCTR1800017102.

Simultaneous achievement of an ultrashort length and a high extinction ratio polarization splitter based on the dual-core photonic crystal fiber with Ge20Sb15Se65 glass.

A polarization splitter based on dual-core photonic crystal fiber with ${{\rm Ge}_{20}}{{\rm Sb}_{15}}{{\rm Se}_{65}}$ glass is proposed to realize ultrashort length and high extinction ratio simultaneously at the common wavelength of 1.55 µm. The characteristics of the polarization splitter have been investigated by the finite element method. By tailoring the structure parameters on the performance of the splitter, the optimized parameters are obtained to analyze the birefringence, the coupling length, the normalized power transfer, and the extinction ratio. A comparison with other designs demonstrates the advantages of our polarization splitter, which can find potential applications in optical communication systems, optical fiber sensing, etc.

Erratum: Superior Stability and Efficiency Over 20% Perovskite Solar Cells Achieved by a Novel Molecularly Engineered Rutin-AgNPs/Thiophene Copolymer.

[This corrects the article DOI: 10.1002/advs.201800568.].

Moisture-tolerant supermolecule for the stability enhancement of organic-inorganic perovskite solar cells in ambient air.

Instability of the perovskite materials, especially in high humidity, is one of the major limitations that hinders the development of perovskite devices. Herein, to eliminate the degradation of perovskite solar cells in humid air, a water-resistant perovskite absorption layer is proposed by introducing a macrocycle-type cyclodextrin material (ß-CD) into the films. The ß-CD was proved to be capable of facilitating the crystallization of grains and enhancing the stability of the perovskite by forming supramolecular interactions with organic cations through the hydrogen bonding in the perovskite films. Consequently, the average efficiency of the PSCs remarkably increased from 16.19% to 19.98%. The champion solar cell even delivered an efficiency of 20.09%. The PSCs with ß-CD exhibited superior long-term stability in ambient air without encapsulation, which retained 90% of the initial efficiency after continuous AM 1.5 illumination in ambient air with 80% humidity for 300 h.

Computational Study of Ternary Devices: Stable, Low-Cost, and Efficient Planar Perovskite Solar Cells.

Although perovskite solar cells with power conversion efficiencies (PCEs) more than 22% have been realized with expensive organic charge-transporting materials, their stability and high cost remain to be addressed. In this work, the perovskite configuration of MAPbX (MA = CH3NH3, X = I3, Br3, or I2Br) integrated with stable and low-cost Cu:NiO x hole-transporting material, ZnO electron-transporting material, and Al counter electrode was modeled as a planar PSC and studied theoretically. A solar cell simulation program (wxAMPS), which served as an update of the popular solar cell simulation tool (AMPS: Analysis of Microelectronic and Photonic Structures), was used. The study yielded a detailed understanding of the role of each component in the solar cell and its effect on the photovoltaic parameters as a whole. The bandgap of active materials and operating temperature of the modeled solar cell were shown to influence the solar cell performance in a significant way. Further, the simulation results reveal a strong dependence of photovoltaic parameters on the thickness and defect density of the light-absorbing layers. Under moderate simulation conditions, the MAPbBr3 and MAPbI2Br cells recorded the highest PCEs of 20.58 and 19.08%, respectively, while MAPbI3 cell gave a value of 16.14%.

Superior Stability and Efficiency Over 20% Perovskite Solar Cells Achieved by a Novel Molecularly Engineered Rutin-AgNPs/Thiophene Copolymer.

Perovskite solar cells (PSCs) with efficiencies greater than 20% have been realized mostly with expensive spiro-MeOTAD hole-transporting material. PSCs are demonstrated that achieve stabilized efficiencies exceeding 20% with straightforward low-cost molecularly engineered copolymer poly(1-(4-hexylphenyl)-2,5-di(thiophen-2-yl)-1H-pyrrole) (PHPT-py) based on Rutin-silver nanoparticles (AgNPs) as the hole extraction layer. The Rutin-AgNPs additive enables the creation of compact, highly conformal PHPT-py layers that facilitate rapid carrier extraction and collection. The spiro-MeOTAD-based PSCs show comparable efficiency, although their operational stability is poor. This instability originated from potential-induced degradation of the spiro-MeOTAD/Au contact. The addition of conductive Rutin-AgNPs into PHPT-py layer allows PSCs to retain >97% of their initial efficiency up to 60 d without encapsulation under relative humidity. The PHPT-py/ Rutin-AgNPs-based devices surpass the stability of spiro-MeOTAD-based PSCs and potentially reduce the fabrication cost of PSCs.

Bystander cardiopulmonary resuscitation training in primary and secondary school children in China and the impact of neighborhood socioeconomic status: A prospective controlled trial.

BACKGROUND: The World Health Organization (WHO) has endorsed school bystander cardiopulmonary resuscitation (CPR) training programs. But related researches in China are limited. Therefore, we conducted this study to assess bystander CPR training in school children in China and the impact of neighborhood socio-economic status (SES) on. METHODS: A total of 1,093 students from seven schools in Zhejiang province participated in this study. Theoretical and practical bystander CPR training were conducted in instructor-led classes. Students completed a 10-statement questionnaire before and after training, and then underwent a skills assessment during a simulated basic life support (BLS) scenario. Subgroup analyses were stratified according to neighborhood SES. RESULTS: Before training, most students (72.83%) had a strong desire to learn bystander CPR and share with others. After training, bystander CPR theory was significantly improved (P < .01), and 92.64% students reached an 85-100% performance rate in a simulated BLS scenario. Students from low-SES neighborhoods had less pre-training knowledge of bystander CPR (P < .01). However, their performance was similar with students from higher-SES neighborhoods on the post-training questionnaire and the skills assessment, and better among students aged 13-14 years. CONCLUSION: School children in China have a poor pre-training knowledge of bystander CPR. However, with training, there was a significant improvement in the basic theory and skills of CPR. Bystander CPR training efforts should be targeted to Chinese primary and secondary school children, especially in low-SES neighborhoods.