Emerging Nonlinear Photocurrents in Lead Halide Perovskites for Spintronics.

Lead halide perovskites (LHPs) containing organic parts are emerging optoelectronic materials with a wide range of applications thanks to their high optical absorption, carrier mobility, and easy preparation methods. They possess spin-dependent properties, such as strong spin-orbit coupling (SOC), and are promising for spintronics. The Rashba effect in LHPs can be manipulated by a magnetic field and a polarized light field. Considering the surfaces and interfaces of LHPs, light polarization-dependent optoelectronics of LHPs has attracted attention, especially in terms of spin-dependent photocurrents (SDPs). Currently, there are intense efforts being made in the identification and separation of SDPs and spin-to-charge interconversion in LHP. Here, we provide a comprehensive review of second-order nonlinear photocurrents in LHP in regard to spintronics. First, a detailed background on Rashba SOC and its related effects (including the inverse Rashba-Edelstein effect) is given. Subsequently, nonlinear photo-induced effects leading to SDPs are presented. Then, SDPs due to the photo-induced inverse spin Hall effect and the circular photogalvanic effect, together with photocurrent due to the photon drag effect, are compared. This is followed by the main focus of nonlinear photocurrents in LHPs containing organic parts, starting from fundamentals related to spin-dependent optoelectronics. Finally, we conclude with a brief summary and future prospects.

Evaluation of the Analytical Properties of the Diagon CoagXL Coagulation Analyzer.

BACKGROUND: This study aims to evaluate the analytical properties of the DIAGON CoagXL (Budapest, Hungary) coagulation system. METHODS: The study includes a total of 212 normal, 49 pathologic plasma samples sent to our laboratory. The par-tial thromboplastin time (PTT) and activated partial thromboplastin time (aPTT) measurements were performed on the Diagon CoagXL and Stago StaR coagulometers. The precision, method comparison, carry-over, activity determination, and reference range verification studies were performed with Diagon CoagXL, the test analyzer. RESULTS: In the precision study performed with normal and pathologic plasma samples for the PT and aPTT tests, the within-day coefficient of variation (CV%) was 1.9 in the normal and 0.68 in the pathologic plasma for the PT, and for the aPTT it was 0.61 in the normal and 0.9 in the pathologic plasma. The between-day CV% was 1.6 in the normal plasma and 5.5 in the pathologic plasma for the PT and 3.7 in the normal plasma and 2.1 in the pathologic plasma for the aPTT. In the comparison study, the entire group mean ± standard deviation (mean ± SD) value for the INR was found to be 3.13 ± 1.26 in the CoagXL and 2.67 ± 0.82 in the StaR analyzer. The difference between these values was statistically significant (p < 0.006). For aPTT, mean ± SD value was found to be 39.44 ± 25.02 seconds (sec) in the CoagXL analyzer and 43.4 ± 27.63 sec in the StaR analyzer. The difference between these values was not statistically significant (p > 0.5). In the carryover study, the carryover value was -0.16 for the PT and 0 for the aPTT, which was under the allowable limit value (< 3 SD). In the percent activity determination study, regression equation of prothrombin activity (%) versus time (sec) was found as y = 341.6567 ± 37.1920x + 1.0913x2 (R2 = 0.97). The reference range verification analyses reveal that the manufacturer ranges were acceptable. CONCLUSIONS: Verification studies of CoagXL analyzer system was acceptable. But in comparison studies of PT we saw that there are still problems with recommended INR system.

Relationship between irritable bowel syndrome and plasma and tissue ghrelin levels.

BACKGROUND/AIMS: This study aimed to evaluate the relationship between irritable bowel syndrome (IBS) and plasma and tissue ghrelin levels. MATERIALS AND METHODS: Patients who had undergone gastroscopy procedure for any reason previously were enrolled in the study. Among these, patients with IBS symptoms were evaluated according to the Roma III criteria. The healthy control group comprised patients with no IBS symptom and had undergone gastroscopy procedure for another reason. The plasma ghrelin level and tissue ghrelin level obtained by immunohistochemical examination of biopsy specimens taken from the gastric antrum and corpus were evaluated in all participants. RESULTS: The mean age of 90 participants was 43.64}12.64 years. The median value of the plasma ghrelin level was 3.29 (1.2-12.7) in the diarrhea group (IBS-D), 1.49 (0.82-7.08) in the constipation group (IBS-C), and 1.5 (0.2-3.7) in the control group. The plasma ghrelin levels between the groups were found to be significantly higher in IBS-D than in IBS-C and the control groups (p=0.001 and p=0.001, respectively). On comparing antral mucosal gland biopsy outcomes among the groups, staining intensity score was found to be significantly high in IBS-C as compared with the control group, whereas no significant difference was observed between IBS-D and the control groups (p=0.020 and p=0.429, respectively). CONCLUSION: The plasma ghrelin level in IBS-D and the staining intensity in the antral mucosal gland in IBS-C were found to be significantly higher. In addition, there was no difference between the groups in terms of ghrelin staining intensity in the gastric corpus.