Ambient Degradation Anisotropy and Mechanism of van der Waals Ferroelectric NbOI2.

The spontaneous centrosymmetry-breaking and robust room-temperature ferroelectricity in niobium oxide dihalides spurs a flurry of explorations into its promising second-order nonlinear optical properties, and promises potential applications in nonvolatile electro-optical and optoelectronic devices. However, the ambient stability of the niobium oxide dihalides remains questionable, which overshadows their future development. In this work, the chemical degradation of NbOI2 is comprehensively investigated using combined chemical and optical microscopies in conjunction with spectroscopies. We unveil the highly anisotropic degradation kinetics of NbOI2 driven by the hydrolysis process of the unstable dangling iodine bonds dominantly on the (010) facet and progressing along the c axis. Knowing its degradation mechanism, the NbOI2 flake can then be stabilized by the hexagonal boron nitride encapsulation, which isolates the air moisture. These findings provide direct insights into the ambient instability of NbOI2, and they deliver possible solutions to circumvent this issue, which are essential for its practical integration in photonic and electronic devices.

Unconventional polarization fatigue in van der Waals layered ferroelectric ionic conductor CuInP2S6.

Recent progress in two-dimensional ferroelectrics greatly expands the versatility and tunability in van der Waals heterostructure based electronics. However, the switching endurance issue that widely plagues conventional ferroelectrics in practical applications is hitherto unexplored for van der Waals layered ferroelectrics. Herein, we report the observation of unusual polarization fatigue behaviors in van der Waals layered CuInP2S6, which also possesses finite ionic conductivity at room temperature. The strong intertwinement of the short-range polarization switching and long-range ionic movement in conjunction with the van der Waals layered structure gives rise to unique morphological and polarization evolutions under repetitive electric cycles. With the help of concerted chemical, structural, lattice vibrational and dielectric analyses, we unravel the critical role of the synergy of ionic migration and surface oxidation on the anomalous polarization enhancement and the eventual polarization degradation. This work provides a general insight into the polarization fatigue characteristics in ionically-active van der Waals ferroelectrics and delivers potential solutions for the realization of fatigue-free capacitors.

Self-Enhancing Photoelectrochemical Properties in van der Waals Ferroelectric CuInP2S6 by Photoassisted Acid Hydrolysis.

Transition metal thiophosphate, CuInP2S6 (CIPS), has recently emerged as a potentially promising material for photoelectrochemical (PEC) water splitting due to its intrinsic ferroelectric polarization for spontaneous photocarrier separation. However, the poor kinetics of the hydrogen evolution reaction (HER) greatly limits its practical applications. Herein, we report self-enhancing photocatalytic behavior of a CIPS photocathode due to chemically driven oxygen incorporation by photoassisted acid oxidation. The optimal oxygen-doped CIPS demonstrates a >1 order of magnitude enhancement in the photocurrent density compared to that of pristine CIPS. Through comprehensive spectroscopic and microscopic investigations combined with theoretical calculations, we disclose that oxygen doping will lower the Fermi level position and decrease the HER barrier, which further accelerates charge separation and improves the HER activity. This work may deliver a universal and facile strategy for improving the PEC performance of other van der Waals metal thiophosphates.

An Analysis of the Correlation Between Clinical Indexes and Pathological Classifications in 202 Patients with Lupus Nephritis.

OBJECTIVE: To investigate the correlation between clinical indexes and pathological classifications in 202 patients with lupus nephritis (LN). METHODS: A total of 202 LN cases were retrospectively analyzed. All these patients met the four diagnostic criteria for systemic lupus erythematosus (SLE) of the American College of Rheumatology revised in 1997. The pathological diagnostic criteria of LN were in accordance with the pathological LN classification revised by the International Society of Nephrology and the Society of Kidney Pathology in 2003. The patients were scored according to the improved SLE Disease Activity Index 2000 (SLEDAI-2K), and their basic data, clinical data, laboratory data, and pathological data were collected. RESULTS: Among the 202 patients, the ratio of male to female was 1:5.73, and type IV was the most common pathological LN classification. There were differences in the urine analysis, hypertension incidence, blood cell analysis, blood lipids, renal function, plasma albumin, immunological indexes, renal pathological score among the different pathological types (P < 0.05). In the early finding of renal function damage of the patients, cystatin C sensitivity was significantly higher than that of serum creatinine and blood urea nitrogen. Multiple linear regression analysis show that there are strong correlations between AI and SLEDAI, 24hU-Pr, serum C3, serum ALB, BUN, creatinine, UA and PLT (P < 0.001); and there are correlations between AI and serum IgM, IgA, C4, TC and LDL-C (P < 0.05). CONCLUSION: There is a clear correlation between pathological classifications and clinical indexes of LN. TRIAL REGISTRATION: Shen-PJ-2018-40, Study on Clinical and Molecular Mechanism of SLE.

Diminution of microRNA-98 alleviates renal fibrosis in diabetic nephropathy by elevating Nedd4L and inactivating TGF-ß/Smad2/3 pathway.

MicroRNAs (miRNAs) have already been documented to function in diabetic nephropathy (DN), yet little research has focused on the role of miR-98 in this disease. Here, we discuss the mechanism of miR-98 on the renal fibrosis in DN. Recombinant adeno-associated virus carrying miR-98 inhibitor or Nedd4L overexpression plasmid was injected into DN modeled rats to explore their roles in DN. Renal tubular epithelial cell injury models (NRK-52E cells) were induced by high glucose (HG). HG-treated NRK-52E cells were transfected with miR-98 inhibitor or Nedd4L overexpression plasmid for further verification. MiR-98 was upregulated, Nedd4L was downregulated and TGF-ß/Smad2/3 signaling was activated in kidney tissues of DN rats and HG-treated NRK-52E cells. miR-98 targeted Nedd4L mRNA 3'UTR. MiR-98 depletion and Nedd4L overexpression inactivated TGF-ß/Smad2/3 signaling pathway, alleviated pathological damage and fibrosis, ameliorated inflammation, and depressed cell apoptosis of kidney tissues of DN rats. MiR-98 depletion and Nedd4L overexpression inactivated TGF-ß/Smad2/3 signaling pathway, strengthened viability, and limited apoptosis of HG-treated renal tubular epithelial cells. Nedd4L overexpression reversed the effect of up-regulating miR-98 on DN rats and HG-treated renal tubular epithelial cells. Altogether, we find that miR-98 is upregulated in kidney tissues of DN rats, and miR-98 diminution and Nedd4L elevation attenuate renal fibrosis through inactivation of the TGF-ß/Smad2/3 pathway, which provides a novel therapy for DN.

Effects of Anisotropy on Single Crystal Silicon in Polishing Non-Continuous Surface.

A molecular dynamics model of the diamond abrasive polishing the single crystal silicon is established. Crystal surfaces of the single crystal silicon in the Y-direction are (010), (011), and (111) surfaces, respectively. The effects of crystallographic orientations on polishing the non-continuous single crystal silicon surfaces are discussed from the aspects of surface morphology, displacement, polishing force, and phase transformation. The simulation results show that the Si(010) surface accumulates chips more easily than Si(011) and Si(111) surfaces. Si(010) and Si(011) workpieces are deformed in the entire pore walls on the entry areas of pores, while the Si(111) workpiece is a local large deformation on entry areas of the pores. Comparing the recovery value of the displacement in different workpieces, it can be seen that the elastic deformation of the A side in the Si(011) workpiece is larger than that of the A side in other workpieces. Pores cause the tangential force and normal force to fluctuate. The fluctuation range of the tangential force is small, and the fluctuation range of the normal force is large. Crystallographic orientations mainly affect the position where the tangential force reaches the maximum and minimum values and the magnitude of the decrease in the tangential force near the pores. The position of the normal force reaching the maximum and minimum values near the pores is basically the same, and different crystallographic orientations have no obvious effect on the drop of the normal force, except for a slight fluctuation in the value. The high-pressure phase transformation is the main way to change the crystal structure. The Si(111) surface is the cleavage surface of single crystal silicon, and the total number of main phase transformation atoms on the Si(111) surface is the largest among the three types of workpieces. In addition, the phase transformation in Si(010) and Si(011) workpieces extends to the bottom of pores, and the Si(111) workpiece does not extend to the bottom of pores.

Gut microbiota trajectory in patients with severe burn: A time series study.

PURPOSE: This time series experiments aimed to investigate the dynamic change of gut microbiomes after severe burn and its association with enteral nutrition (EN). MATERIALS AND METHODS: Seven severely burned patients who suffered from a severe metal dust explosion injury were recruited in this study. The dynamic changes of gut microbiome of fecal samples at six time points (1-3days, 2, 3, 4, 5 and 6weeks after severe burn) were detected using 16S ribosomal RNA pyrosequencing technology. RESULTS: Following the post-burn temporal order, gut microbiota dysbiosis was detected in the gut microbiome after severe burn, then it was gradually resolved. The bio-diversity of gut bacteria was initially decreased, and then returned to normal level. In addition, at the early stage (from 2 to 4weeks), the majority of those patients' gut microbiome were opportunistic pathogen genus, Enterococcus and Escherichia; while at the end of this study, the majority was a beneficial genus, Bacteroides. EN can promote the recovery of gut microbiota, especially in EN well-tolerated patients. CONCLUSIONS: Severe burn injury can cause a dramatic dysbiosis of gut microbiota. A trend of enriched beneficial bacteria and diminished opportunistic pathogen bacteria may serve as prognosis microbiome biomarkers of severe burn patients.

[Clinical observation of Clarithromycin combined with nasal steroid treatment for chronic rhinosinusitis].

OBJECTIVE: To observe the clinical treatment effectiveness of Clarithromycin combined with nasal glucocorticoids for chronic rhinosinusitis (CRS). METHOD: Clarithromycin was 0.25 g a day (the first two weeks was 0.25 g twice a day) and topical Triamcinolone Acetonide Acetate nasal spray was (220 microg/d) once a day. Fifty-six patients were enrolled in our research. Twenty-six patients of CRS without nasal polyps was treated for 12 to 28 weeks (average 16.62 weeks). Thirty patients of CRS with nasal polyps was treated for 12 to 33 weeks (average 20.03 weeks) after polypectomy. The patients' symptom were evaluated through Sino-Nasal Outcome Test 20 (SNOT-20) scale. Meanwhile sinus CT were evaluated by Lund-Mackey system before and after operation. RESULT: The score of CT scan was significantly decreased to 2.83 +/- 1.86 (t = 11.41, P < 0.01) in the CRS with nasal polyps group and to 2.43 +/- 1.91 (t = 12.86, P < 0.01) in the CRS without nasal polyps group after treatment. Recovery rate of CRS with nasal polyps group was 43.3% and of CRS without nasal polyps group was 50.0% with CT images. The self assessments of treatment efficiency was coincident with CT image in the two groups. CONCLUSION: The treatment with Long term use of low dosage oral macrolide Clarithromycin combined with nasal steroid on CRS was efficacy. Polypectomy ,large dose antibiotic and steroid used in intraoperative period could significant improve the treatment efficiency of CRS with nasal polyps.

[Morphological study of adenoid by endoscopy and its clinical significance].

OBJECTIVE: To observe the natural process of adenoid growth and degeneration as the age grows, to investigate the related clinical significance and pathologic characteristics of hypertrophied adenoid. METHODS: Totally 2650 (age 2 to 87) cases with nasal obstruction or/and other symptoms were included in the patients group, and 810 (age 3 to 85) subjects without symptoms were included as the control group. Morphological characteristics examined with nasal endoscope. Biopsy was performed for 39 cases. The adenoid was calcified as 4 degrees according to the size. RESULTS: In the patient group, age 2 to 9, degree III and degree II adenoid were 81.1% (198/244) and 18.9% (46/244) respectively. And adenoid of children whose age 2 to 5 was 100.0% in degree III; In above 10 years old group, the adenoid was mostly degree II. In age 60 to 69 group, degree 0 was (66.5%), and in age 81 or above, degree 0 reaches 100%. And 19 years old was the youngest age at which adenoid of degree 0 started to be found and 21 was the oldest age at which there is no adenoid of degree III. In the control group, compared with the patient group, no statistical significant difference found in all other groups except in age 2 to 9 (degree III 57.9%, 22/38, degree II 42.1%, 16/38). Shapes of adenoids at degree II varied while degree I were almost like peeled orange. Pathologically, among children there are abundant of adenoidal lymph tissue, while in adults the lymph tissue getting less as age grows but with evident inflammation reaction. Among patients, the incidence of sinusitis and snoring was higher in degree III group compared with others, 47.4% and 18.7% respectively, and the differences is statistically significant (chi2 = 51.28, P < 0.01; chi2 = 40.26, P < 0.01). CONCLUSIONS: Adenoid volume of children (age < 10) is the biggest, especially of children under 5 years old.