Self-Assembly of Delta-Formamidinium Lead Iodide Nanoparticles to Nanorods: Study of Memristor Properties and Resistive Switching Mechanism.

In the quest for advanced memristor technologies, this study introduces the synthesis of delta-formamidinium lead iodide (δ-FAPbI3) nanoparticles (NPs) and their self-assembly into nanorods (NRs). The formation of these NRs is facilitated by iodide vacancies, promoting the fusion of individual NPs at higher concentrations. Notably, these NRs exhibit robust stability under ambient conditions, a distinctive advantage attributed to the presence of capping ligands and a crystal lattice structured around face-sharing octahedra. When employed as the active layer in resistive random-access memory devices, these NRs demonstrate exceptional bipolar switching properties. A remarkable on/off ratio (105) is achieved, surpassing the performances of previously reported low-dimensional perovskite derivatives and α-FAPbI3 NP-based devices. This enhanced performance is attributed to the low off-state current owing to the reduced number of halide vacancies, intrinsic low dimensionality, and the parallel alignment of NRs on the FTO substrate. This study not only provides significant insights into the development of superior materials for memristor applications but also opens new avenues for exploring low-dimensional perovskite derivatives in advanced electronic devices.

Effect of cigarette smoking on major histological types of lung cancer in men.

This study examined the effect of cigarette smoking parameters such as intensity, duration, age at initiation, and quitting on the development of different histological types of lung cancer in men. We used data from a case-control study conducted in Philadelphia between 1985 and 1987. Cases included 482 men with histologically confirmed lung cancer diagnosed in 15 selected hospitals in Philadelphia. Controls were selected from a neighborhood survey of men in Philadelphia conducted concurrently to the case recruitment. Most aspects of smoking were associated with all the major histological types of lung cancer. Number of cigarettes smoked per day was the strongest predictor of risk of developing lung cancer. Early age at initiation of smoking significantly increased the risk of small cell carcinoma (odds ratio = 3.0; 95% CI, 1.1-8.4). Quitting smoking reduced the risk of squamous cell and adenocarcinoma; however, it did not affect the risk of small cell lung cancer. The findings of this study suggest the need for greater emphasis on smoking prevention programs, especially in adolescents.

Extracorporeal membrane oxygenation support as a bridge to pediatric heart transplantation.

BACKGROUND: Mechanical circulatory support for intractable heart failure as a bridge to transplantation has been used infrequently in children. The lack of clinically available ventricular assist devices has resulted in the use of conventional extracorporeal circuits with oxygenator as the main modality for circulatory support. In this study we reviewed our experience with extracorporeal membrane oxygenation (ECMO) support in children with irreversible heart failure who were awaiting heart transplantation. METHODS AND RESULTS: Since 1985, 14 children were placed on ECMO support for circulatory failure and were considered candidates for heart transplantation: 8 children had postcardiotomy contractile failure, 3 had dilated cardiomyopathy, and 3 had viral myocarditis. Five of these children had cardiac arrest and were placed on support during cardiopulmonary resuscitation. Mean duration of ECMO support was 109 +/- 20 hours. Eight patients developed pulmonary edema requiring decompression of the left ventricle, 3 by blade atrial septostomy and 5 by left atrial vent cannula. Nine of 14 received a heart transplant, 1 child recovered spontaneously (myocarditis), and 4 died of sepsis on ECMO. Of the children who received transplants, 6 were early survivors with 1 late death (lymphoproliferative disease), for a total of 7 of 14 (50%) early and 6 of 14 (43%) late survivors. CONCLUSIONS: Our experience suggests that ECMO is an effective means of circulatory support as a bridge to transplantation in children. Decompression of the left ventricle is often required to prevent pulmonary edema. Sepsis and bleeding remain a limitation to prolonged mechanical support with ECMO in children.

Median cleft lip with bimanual hexadactyly and bilateral accessory toes. Report of two cases in the same family.

The present paper presents two brothers with a median upper lip cleft, associated with postaxial hexadactyly of both hands and feet. Very few similar cases have previously been reported in the literature by various workers. The similarity between the cases reported in the literature and the two cases presented here indicates the existence of a median cleft lip-hexadactyly-syndrome.