Unprecedented atomic surface of silicon induced by environmentally friendly chemical mechanical polishing.

Silicon (Si) dominates the integrated circuit (IC), semiconductor, and microelectronic industries. However, it is a challenge to achieve a sub-angstrom surface of Si. Chemical mechanical polishing (CMP) is widely used in the manufacturing of Si, while toxic and polluted slurries are usually employed in CMP, resulting in pollution to the environment. In this study, a novel environmentally friendly CMP was developed, in which a slurry is composed of ceria, hydrogen peroxide, sodium pyrophosphate, sodium carboxymethyl cellulose, sodium carbonate, and deionized water. After CMP, the surface roughness Sa was 0.067 nm with a measurement area of 50 × 50 µm2, and a sub-angstrom surface is achieved. To the best of our knowledge, it is the lowest surface roughness in such a large area. Transmission electron microscopy shows that the thickness of the damaged layer after CMP is 2.8 nm. X-ray photoelectron spectroscopy and infrared Fourier transformation reveal that during CMP, a redox reaction firstly took place between Ce3+ and Ce4+. Si and ceria are hydroxylated, forming Si-OH and Ce-OH, then dehydration and condensation occur, generating Si-O-Ce. These findings propose new insights to fabricate a sub-angstrom surface of Si for use in IC, semiconductor, and microelectronic industries.

A meta-analysis to investigate the role of magnetic resonance spectroscopy in the detection of temporal lobe epilepsy.

BACKGROUND: Temporal lobe epilepsy (TLE) is a complex neuropsychiatric illness that alters patient's behavior and social well-being. Early and accurate diagnosis of TLE is a key factor in its treatment. Currently, magnetic resonance spectroscopy (MRS) is recommended due to its high sensitivity and specificity in the detection of seizures. However, some studies have reported on its limited role in lesion detection. OBJECTIVES: The present meta-analysis aims to analyze different studies thoroughly and investigate the role of MRS in the detection of TLE. MATERIAL AND METHODS: A systematic literature review was conducted using Medline (via PubMed), Cinahl (via EBSCO), Scopus, and Web of Sciences databases for case-control, retrospective and prospective studies regarding the use of MRS in detecting TLE. Studies were included using the Population, Intervention, Comparison, Outcomes and Study (PICOS) criteria and relevant event data were extracted. The risk of publication bias was analyzed using the Begg and Mazumdar test. A risk of bias assessment was conducted using RevMan software. The Mantel-Haenszel method was used to calculate the sensitivity, pooled odds ratio (OR), and risk ratio (RR), also using RevMan software. RESULTS: A total of 16 studies published between 2000 and 2022 were included, which encompassed a total of 645 patients. We obtained a high sensitivity of 84.8%, which shows a high efficiency of MRS, and a pooled OR value of 0.37 (95% confidence interval (95% CI): 0.14-0.97) with a tau2 value of 2.63, χ2 value of 84.99, degrees of freedom (df) value of 15, I2 value of 82%, Z-value of 2.03, and p < 0.05. The pooled RR was 0.82 (95% CI: 0.69-0.97) with a tau2 value of 0.10, χ2 value of 122.11, df of 15, I2 value of 88%, Z-value of 2.25, and p < 0.05. These results were statistically significant for a low risk of publication bias. CONCLUSION: The current meta-analysis highly recommends the use of MRS in the accurate detection of alterations seen in the brain in patients with TLE.

Determining the origin and fate of nitrate in the Nanyang Basin, Central China, using environmental isotopes and the Bayesian mixing model.

Identifying sources of nitrate contamination has been a long-term challenge in areas with different land uses. We investigated the biogeochemical processes and quantified the contribution of potential nitrate sources in the Nanyang Basin, the source area of the South to North Water Diversion Project in China. Hydrogeochemical characteristics, the dual-isotope method (δ15N-NO3- and δ18O-NO3-), and the Bayesian mixing model (SIAR) were combined. The results for 160 samples indicated that mean nitrate concentrations of residential area (162.83 mg L-1) and farmland (75.71 mg L-1) were higher compared with those of surface water (16.15 mg L-1) and forest (36.25 mg L-1). Hydrochemical facies and molar ratios of major ions indicated that the natural environment was greatly impacted by anthropogenic activities. Nitrification, ammonium volatilization, and mixing effects were the dominant processes in nitrogen transformation. The contributions of different sources to nitrate contamination were 45.41%, 35.81%, 17.87%, and 0.91% for sewage and manure, soil organic nitrogen, synthetic fertilizer, and atmospheric deposition, respectively. Undeveloped infrastructure and sewage disposal in rural areas were the main causes of nitrate contamination. Our results provide a theoretical basis for the development of measures to guarantee long-term water supply of the South to North Water Diversion Project.

Abnormal default-mode network homogeneity in patients with temporal lobe epilepsy.

Default-mode network (DMN) plays a key role in a broad-scale cognitive problem, which occurs in temporal lobe epilepsy (TLE). However, little is known about the alterations of the network homogeneity (NH) of DMN in TLE. In the present study, we employed NH method to investigate the NH of DMN in TLE at rest.A total of 47 patients with TLE (right TLE [rTLE] 29, and left TLE [lTLE] 18) and 35 healthy controls who underwent resting-state functional magnetic resonance imaging were enrolled. NH approach was used to analyze the data.rTLE exhibited decreased NH in the right middle temporal pole gyrus and increased NH in the bilateral posterior cingulate cortex compared to the control group. In lTLE, decreased NH was observed in left inferior temporal gyrus and left hippocampus. Meanwhile, we found that lTLE had a longer performance reaction time. No significant correlation was found between abnormal NH values and clinical variables in the patients.These findings suggested that abnormal NH of the DMN exists in rTLE and lTLE, and highlighted the significance of DMN in the pathophysiology of cognitive problems occurring in TLE and also found the existence of abnormality of executive function in lTLE.

Decreased functional connectivity and structural deficit in alertness network with right-sided temporal lobe epilepsy.

Patients with temporal lobe epilepsy (TLE) often suffer from alertness alterations. However, specific regions connected with alertness remain controversial, and whether these regions have structural impairment is also elusive. This study aimed to investigate the characteristics and neural mechanisms underlying the functions and structures of alertness network in patients with right-sided temporal lobe epilepsy (rTLE) by performing the attentional network test (ANT), resting-state functional magnetic resonance imaging (R-SfMRI), and diffusion tensor imaging (DTI).A total of 47 patients with rTLE and 34 healthy controls underwent ANT, R-SfMRI, and DTI scan. The seed-based functional connectivity (FC) method and deterministic tractography were used to analyze the data.Patients with rTLE had longer reaction times in the no-cue and double-cue conditions. However, no differences were noted in the alertness effect between the 2 groups. The patient group had lower FC compared with the control group in the right inferior parietal lobe (IPL), amygdala, and insula. Structural deficits were found in the right parahippocampal gyrus, superior temporal pole, insula, and amygdala in the patient group compared with the control group. Also significantly negative correlations were observed between abnormal fractional anisotropy (between the right insula and the superior temporal pole) and illness duration in the patients with rTLE.The findings of this study suggested abnormal intrinsic and phasic alertness, decreased FC, and structural deficits within the alerting network in the rTLE. This study provided new insights into the mechanisms of alertness alterations in rTLE.

Abnormal Default Mode Network Homogeneity in Treatment-Naive Patients With First-Episode Depression.

Background and Objective: The default mode network (DMN) may be an important component involved in the broad-scale cognitive problems seen in patients with first-episode treatment-naive depression. Nevertheless, information is scarce regarding the changes in network homogeneity (NH) found in the DMN of these patients. Therefore, in this study, we explored the NH of the DMN in patients with first-episode treatment-naive depression. Methods: The study included 66 patients and 74 control participants matched by age, gender, educational level and health status who underwent resting-state functional magnetic resonance imaging (rs-fMRI) and the attentional network test (ANT). To assess data, the study utilizes NH and independent component analysis (ICA). Additionally, Spearman's rank correlation analysis is performed among significantly abnormal NH in depression patients and clinical measurements and executive control reaction time (ECRT). Results: In comparison with the control group, patients with first-episode treatment-naive depression showed lower NH in the bilateral angular gyrus (AG), as well as increased NH in the bilateral precuneus (PCu) and posterior cingulate cortex (PCC). Likewise, patients with first-episode treatment-naive depression had longer ECRT. No significant relation was found between abnormal NH values and the measured clinical variables. Conclusions: Our results suggest patients with first-episode treatment-naive depression have abnormal NH values in the DMN. This highlights the significance of DMN in the pathophysiology of cognitive problems in depression. Our study also found alterations in executive functions in patients with first-episode treatment-naive depression.

Interleukin-17A promotes functional activation of systemic sclerosis patient-derived dermal vascular smooth muscle cells by extracellular-regulated protein kinases signalling pathway.

INTRODUCTION: Dermal vascular smooth muscle cells (DVSMCs) are important for vascular wall fibrosis in microangiopathy of systemic sclerosis (SSc). T helper 17 cell-associated cytokines, particularly interleukin-17A (IL-17A), have been demonstrated to play a role in the pathogenesis of SSc. However, the effect of IL-17A on the DVSMCs in microangiopathy of SSc has not been established. In the present study, we investigated the effect of IL-17A on the SSc patient-derived DVSMCs. METHODS: DVSMCs from patients with SSc and healthy subjects were incubated using IL-17A or serum derived from patients with SSc. Subsequently, the proliferation, collagen synthesis and secretion, and migration of DVSMCs were analysed using a cell counting kit-8 (CCK-8), dual-luciferase reporter assay, real-time reverse transcription-polymerase chain reaction (RT-PCR), Western blot, enzyme-linked immunosorbent assay (ELISA) and transwell assay. The protein phosphorylation of signalling pathways in the process of IL-17A-mediated DVSMC activation was investigated and validated by specific signalling pathway inhibitor. RESULTS: IL-17A and serum from patients with SSc could promote the proliferation, collagen synthesis and secretion, and migration of DVSMCs. IL-17A neutralising antibody could inhibit the IL-17A-induced activation of DVSMCs. Additionally, IL-17A induced the activation of extracellular-regulated protein kinases 1/2 (ERK1/2) in DVSMCs, and ERK1/2 inhibitor could block the IL-17A-elicited activation of DVSMCs. CONCLUSIONS: Our results suggested that IL-17A derived from patients with SSc might induce the proliferation, collagen synthesis and secretion, and migration of DVSMCs via ERK1/2 signalling pathway, raising the likelihood that IL-17A and ERK1/2 might be promising therapeutic targets for the treatment of SSc-related vasculopathy.

Analysis of SCA2 and SCA3/MJD repeats in Parkinson's disease in mainland China: genetic, clinical, and positron emission tomography findings.

To investigate the prevalence and clinical feature(s) of Parkinson's disease (PD) patients with expanded (ATXN2 and MJD1) genes of spinocerebellar ataxia type 2 and 3 (SCA2 and SCA3/MJD) in a mainland Chinese population, CAG triplet repeat expansions of (SCA2 and SCA3/MJD) genes (ATXN2 and MJD1) were analyzed in a cohort of 452 PD patients, including 386 sporadic and 66 familial forms. Striatal dopamine transporter was evaluated in two SCA2 and two SCA3/MJD-positive family members, an idiopathic PD patient and a healthy control using carbon (C11) [(11)C]-radiolabeled-CFT positron emission tomography (PET). We found two patients in one familial PD (FPD) family (1.5%) and two sporadic PD patients (0.5%) with expanded CAG repeats in the ATXN2 locus, four patients in two FPD families (3%) and another three sporadic PD patients (0.8%) in the MJD1 locus. [(11)C]-CFT PET in detected members in SCA2 and SCA3/MJD families showed decrements of (11)C-CFT uptake. These findings suggest that a mutation in SCA2 or SCA3/MJD may be one of the genetic causes of PD.