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1.
Encephale ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38971647

ABSTRACT

Autism spectrum disorders (ASD) are neurodevelopmental disorders of varying intensity and disability. The reference health strategy in France for the care of young children with autism is day care hospital (DCH). As the number of places in DCH is insufficient, medically coordinated care programs by the mental health consultation centers (MHCC) are being developed in response. OBJECTIVES: Our objective is to evaluate the effectiveness of a medically coordinated care program in a MHCC versus the care in DCH of child psychiatry. METHODS: Non-inferiority retrospective study comparing the evolution after one year of care of 20 ASD children divided into two groups DCH and MHCC. In the DCH ASD group, the child is taken care of two half-days a week in a day hospital with individual educational care. In the MHCC ASD group, the child benefits from a medically coordinated care program. The medical care is reinforced by more frequent and longer consultations with guidance offered to parents. In both groups, the child receives speech therapy and psychomotor therapy in private practice at the same rate. Comparison is made using a composite criterion associating CARS-2 and VABS-II. Non-inferiority of the medically coordinated care program in autism in reference to DCH was tested on the difference between the changes (DCH group variation - MHCC group variation) with a non-inferiority threshold of 10% of the initial value of each score. RESULTS: We observed a reduction in autism severity at the CARS-2 and a moderate improvement in socio-adaptive behavior at the VABS-II in both groups. This trend was even more pronounced in the MHCC group than in the DCH group, but only the greater reduction in CARS-2 severity in the MHCC was statistically significant. CONCLUSIONS: As it is necessary to integrate the two scales into the composite criterion, it is not possible to retain the non-inferiority of the MHCC with care program. However, both those children followed in DCH and those in the MHCC care program progress. This shows the relevance of the care offered at the MHCC for children suffering from ASD, in the context of a growing lack of space in DCH. The continuation of this research work through multicenter studies with larger numbers could demonstrate the non-inferiority of coordinated care programs in the MHCC versus DCH. It would also allow subgroups to be set up, taking into account the initial characteristics of the children in order to have more precise indications concerning the relevance of each treatment.

2.
Micromachines (Basel) ; 15(6)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38930724

ABSTRACT

To elucidate the atomic mechanisms of the chemical mechanical polishing (CMP) of silicon carbide (SiC), molecular dynamics simulations based on a reactive force field were used to study the sliding process of silica (SiO2) abrasive particles on SiC substrates in an aqueous H2O2 solution. During the CMP process, the formation of Si-O-Si interfacial bridge bonds and the insertion of O atoms at the surface can lead to the breakage of Si-C bonds and even the complete removal of SiC atoms. Furthermore, the removal of C atoms is more difficult than the removal of Si atoms. It is found that the removal of Si atoms largely influences the removal of C atoms. The removal of Si atoms can destroy the lattice structure of the substrate surface, leading the neighboring C atoms to be bumped or even completely removed. Our research shows that the material removal during SiC CMP is a comprehensive result of different atomic-level removal mechanisms, where the formation of Si-O-Si interfacial bridge bonds is widespread throughout the SiC polishing process. The Si-O-Si interfacial bridge bonds are the main removal mechanisms for SiC atoms. This study provides a new idea for improving the SiC removal process and studying the mechanism during CMP.

3.
Materials (Basel) ; 17(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38730807

ABSTRACT

CeO2 is widely used in the field of chemical-mechanical polishing for integrated circuits. Morphology, particle size, crystallinity, and Ce3+ concentration are crucial factors that affect polishing performance. In this study, we successfully synthesized two novel triangular CeO2 abrasives with similar particle sizes (600 nm) but different morphologies and Ce3+ concentrations using a microwave-assisted hydrothermal method with high-concentration raw materials, and no surfactants or template agents were added. It is generally believed that CeO2 with a higher Ce3+ concentration leads to better polishing performance. However, the results of polishing indicate that CeO2 synthesized at 200 °C, despite its lower Ce3+ concentration, demonstrates outstanding polishing performance, achieving a polishing rate of 324 nm/min, and the Sa of Si wafers decreased by 3.6% after polishing. This suggests that, under similar particle size conditions, the morphology of CeO2 plays a dominant role in the mechanical effects during the polishing process. Additionally, compared to commercial polishing slurries, the synthesized samples demonstrated better polishing performance. This indicates that, in CMP, the pursuit of smaller spherical abrasives may not be necessary. Instead, the appropriate shape and particle size can better balance the material removal rate and surface roughness.

4.
Biosens Bioelectron ; 259: 116402, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38788342

ABSTRACT

In this work, a high-performance conjugated microporous polymer (CMP) decorated with BiOBr (Tr(PhXOD)3-CMP/BiOBr) is synthesized to application in construction of ultrasensitive photoelectrochemical (PEC) biosensor for sensing miRNA-122, by firstly coupling with efficient clip toehold-mediated allosteric bicycle strand displacement (ABSD). Notably, the Tr(PhXOD)3-CMP/BiOBr not only owns self-enhanced D-A-D structure that extremely shortens migration distance of photo-generated electron, but also forms Z-type heterostructure for accelerating electron-hole separation, thereby significantly enhancing the photocurrent with 10-fold higher than commonly used methods. Meanwhile, the clip toehold-mediated ABSD based on ternary linkage structure transformation avoids the attrition of invading strand, endowing the conservation of high concentration for undergoing rapid reaction with high-efficiency DNA amplification, which dramatically improves reaction time and superior target conversion. The experimental results indicate that proposed PEC biosensor had a high sensitivity to miRNA-122 with a detection limit of 0.49 fM, which provides a newly organic/inorganic photosensitive nanomaterials and efficient DNA strand displacement in bioanalytical and early clinical disease diagnosis.


Subject(s)
Biosensing Techniques , Limit of Detection , MicroRNAs , Polymers , Biosensing Techniques/methods , Polymers/chemistry , MicroRNAs/analysis , Electrochemical Techniques/methods , Humans , DNA/chemistry
5.
Materials (Basel) ; 17(3)2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38591510

ABSTRACT

Silicon carbide, a third-generation semiconductor material, is widely used in the creation of high-power devices. In this article, we systematically study the influence of three crucial parameters on the polishing rate of a silicon carbide surface using orthogonal experiments. By optimizing the parameters of chemical mechanical polishing (CMP) through experiments, we determined that the material removal rate (MRR) is 1.2 µm/h and the surface roughness (Ra) is 0.093 nm. Analysis of the relevant polishing mechanism revealed that manganese dioxide formed during the polishing process. Finally, due to the electrostatic effect of the two, MnO2 adsorbed on the Al2O3, which explains the polishing mechanism of Al2O3 in the slurry.

6.
Materials (Basel) ; 17(8)2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38673174

ABSTRACT

Chemical mechanical planarization (CMP) reduces film thickness, eliminates step height, and achieves high levels of planarity in semiconductor manufacturing. However, research into its mechanisms is still in progress, and there are many issues to be resolved. To solve problems in CMP, it is necessary to understand the contact phenomenon that occurs at the pad-wafer interface, especially pad asperity. Moreover, understanding the non-uniform distribution of pad asperity, such as height and radius, is essential for predicting the material removal rate (MRR). In this study, based on the existing Greenwood-Williamson (GW) theory and probability density function (PDF), a modified mathematical model that includes changes in asperity distribution was developed and validated experimentally. The contact model proposed in this study included functions that calculated the time-dependent height and radius wear of the pad asperities. Specifically, the experimentally obtained values were compared with the values obtained by the model, and the comparison results were analyzed. Thereby, it was found that the contact model and MRR model considering the change in asperity wear and distribution due to CMP proposed in this study are in better agreement with the experimental results than the existing model, which shows that the MRR can be predicted by a mathematical model using the change in asperity distribution.

7.
Micromachines (Basel) ; 15(4)2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38675360

ABSTRACT

As a planarization technique, chemical mechanical polishing (CMP) continues to suffer from pattern effects that result in large variations in material thickness, which can influence circuit performance and yield. Therefore, tools for predicting post-CMP chip morphology based on the layout-dependent effect (LDE) have become increasingly critical and widely utilized for design verification and manufacturing development. In order to characterize the impact of patterns on polishing, such models often require the extraction of graphic parameters. However, existing extraction algorithms provide a limited description of the interaction effect between layout patterns. To address this problem, we calculate the average density as a density correction and innovatively use a one-dimensional line contact deformation profile as a weighting function. To verify our hypothesis, the density correction method is applied to a density step-height-based high-K metal gate-CMP prediction model. The surface prediction results before and after optimization are compared with the silicon data. The results show a reduction in mean squared error (MSE) of 40.1% and 35.2% in oxide and Al height predictions, respectively, compared with the preoptimization results, confirming that the optimization method can improve the prediction accuracy of the model.

8.
Ann Cardiothorac Surg ; 13(2): 165-172, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38590995

ABSTRACT

Background: Thoracoscopic ablation (TA) has emerged as a promising treatment for atrial fibrillation (AF), with the Cox-Maze IV Procedure (CMP-IV) as the current gold-standard intervention. This study aims to evaluate and compare the outcomes of TA and CMP-IV in treating AF. Methods: Patients with AF underwent either CMP-IV or TA through a left-side chest approach. The CMP-IV entailed bi-atrium ablation, whereas the TA involved creating three circular plus three linear ablations in the left atrium. We analyzed baseline characteristics, perioperative outcomes and recurrence rates using propensity score matching (PSM) at a 1:1 ratio, to ensure comparability between the two treatment groups. Results: A total of 459 patients underwent either CMP-IV (n=93) or TA via left chest (n=366) and 174 patients were deemed eligible for 1:1 PSM. The TA group experienced significantly shorter intensive care unit (ICU) and hospital stays. The mean follow-up period was 31.5±22.1 months. Pre- and post-matching analysis showed that CMP-IV had a higher rate of freedom from recurrence compared to TA, particularly in non-paroxysmal AF patients. Multivariable Cox regression analysis revealed that CMP-IV was associated with a reduced risk of recurrence, while an increased left atrial size emerged as an independent predictor of postoperative recurrence, regardless of the use of CMP-IV or TA. Conclusions: Our study suggests that while the therapeutic efficacy of TA for "lone" AF may fall short of the classic CMP-IV, its less invasive nature results in significantly shorter ICU and hospital stays. To enhance patient outcomes following TA, it is essential to improve the quality of ablation, refine the ablation route, and focus on careful patient selection.

9.
Polymers (Basel) ; 16(6)2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38543450

ABSTRACT

Chemical mechanical polishing/planarization (CMP) is an essential manufacturing process in semiconductor technologies. This method combines chemical and mechanical forces to smooth the surfaces of wafers. The effectiveness of CMP relies on a carefully chosen slurry, demanding a sophisticated manufacturing technology. This technology must seamlessly integrate both chemical composition and mechanical elements, highlighting the intricate synergy required for successful semiconductor fabrication. Particularly in milling processes, if agglomerated particles due to slurry particle corrosion are present during polishing, uneven polishing, numerous fine scratches occur, leading to an increase in roughness and a deterioration in the quality of the finished surface. In this study, to overcome the issue of particle agglomeration and uneven polishing in commonly used ceria nanoparticle slurries during CMP processes, we investigated the ceria nanoparticle behavior based on styrene-maleic acid (SMA) dispersant polymer applied with three types of defoaming polymers. The investigations are expected to open up the possibility of utilizing ceria nanoparticles with applied defoaming polymer as an abrasive for advanced CMP applications. All samples were characterized by DLS (dynamic light scattering), SEM-EDX (scanning electron microscopy-energy dispersive X-ray spectroscopy), pH, conductivity, viscosity, a 10-day stability test at 60 °C, the AF4 test, and the polishing rate efficiency test. Our research demonstrates a significant improvement achieved through the use of SMA dispersant polymer, resulting in a polishing selection ratio exceeding 80 for oxide and nitride films. The G-336 defoaming polymer utilized here is expected to serve as a viable alternative in CMP processes by providing stable uniformity.

10.
Indian J Surg Oncol ; 15(Suppl 1): 3-10, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38545572

ABSTRACT

The aim of this study is to evaluate the level of accuracy and precision of bone scan (BS), MRI, and digital radiography (DR) to measure long bone tumors to design custom-made prosthesis (CMP)/modular prosthesis (MP) in limb salvage surgery (LSS) with the help of phantom and patient's study. There are two separate groups: one is the phantom study and another one is the patient's study. The phantom study is done with the Jaszack Phantom for the Gamma camera and the indigenous phantom for the MRI and DR. Three independent imaging professionals (nuclear medicine physicians and radiologists) measured the distance between standardized, preselected points on the Jaszack phantom in the Gamma Camera (GC) and indigenous phantom on the coronal and sagittal view of the MRI scan and in digital radiography. The measured values were compared with the known values for phantom measurement. A total of 36 patients, which include 24 males and 12 females, 3 independent imaging professionals measured the patient's long bone in a bone scan, MRI and DR and compared it with histopathological specimen measurement after limb salvage surgery (LSS). Descriptive statistics using appropriate measures of central tendency and dispersion were employed to describe the data. Karl-Pearson correlation coefficient was used to establish the association between continuous covariates. Paired t-test was utilized to test the differences in paired values for statistical significance. A near-perfect positive correlation was evident between all three pairs of bone scan, MRI scan, and digital radiography values, and a positive agreement within 1 mm of the bone scan, MRI scan, and DR values of all three pairs was around 95%. For the phantom study, we conclude that Gamma camera and MRI measurements are equal in physical measurements (MCF-1). DR measurements were found to be near equal physical measurements and multiplication correction factor (MCF)-0.9104 and three observer's measurements values were also near normal. For the patient's study, we conclude that the bone scan, MRI, and DR measurements of 3 independent imaging professionals are near normal, and it was confirmed with pathological specimen after LSS, to confirm reliability, repeatability, reproducibility, and accuracy of the tumor length to do custom-made prosthesis or modular prosthesis for the patients who are affected by osteosarcoma and Ewing's sarcoma.

11.
Small ; 20(27): e2307828, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38368249

ABSTRACT

In recent years, there has been considerable focus on the development of charge transfer (CT) complex formation as a means to modify the band gaps of organic materials. In particular, CT complexes alternate layers of aromatic molecules with donor (D) and acceptor (A) properties to provide inherent electrical conductivity. In particular, the synthetic porous frameworks as attractive D-A components have been extensively studied in recent years in comparison to existing D-A materials. Therefore, in this work, the synthetic porous frameworks are classified into conjugated microporous polymers (CMPs), covalent organic frameworks (COFs), and metal-organic frameworks (MOFs) and compare high-quality materials for CT in semiconductors. This work updates the overview of the above porous frameworks for CT, starting with their early history regarding their semiconductor applications, and lists CT concepts and selected key developments in their CT complexes and CT composites. In addition, the network formation methods and their functionalization are discussed to provide access to a variety of potential applications. Furthermore, several theoretical investigations, efficiency improvement techniques, and a discussion of the electrical conductivity of the porous frameworks are also highlighted. Finally, a perspective of synthetic porous framework studies on CT performance is provided along with some comparisons.

12.
EBioMedicine ; 101: 105027, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38418263

ABSTRACT

BACKGROUND: Cardiomyopathy is a clinically and genetically heterogeneous heart condition that can lead to heart failure and sudden cardiac death in childhood. While it has a strong genetic basis, the genetic aetiology for over 50% of cardiomyopathy cases remains unknown. METHODS: In this study, we analyse the characteristics of tandem repeats from genome sequence data of unrelated individuals diagnosed with cardiomyopathy from Canada and the United Kingdom (n = 1216) and compare them to those found in the general population. We perform burden analysis to identify genomic and epigenomic features that are impacted by rare tandem repeat expansions (TREs), and enrichment analysis to identify functional pathways that are involved in the TRE-associated genes in cardiomyopathy. We use Oxford Nanopore targeted long-read sequencing to validate repeat size and methylation status of one of the most recurrent TREs. We also compare the TRE-associated genes to those that are dysregulated in the heart tissues of individuals with cardiomyopathy. FINDINGS: We demonstrate that tandem repeats that are rarely expanded in the general population are predominantly expanded in cardiomyopathy. We find that rare TREs are disproportionately present in constrained genes near transcriptional start sites, have high GC content, and frequently overlap active enhancer H3K27ac marks, where expansion-related DNA methylation may reduce gene expression. We demonstrate the gene silencing effect of expanded CGG tandem repeats in DIP2B through promoter hypermethylation. We show that the enhancer-associated loci are found in genes that are highly expressed in human cardiomyocytes and are differentially expressed in the left ventricle of the heart in individuals with cardiomyopathy. INTERPRETATION: Our findings highlight the underrecognized contribution of rare tandem repeat expansions to the risk of cardiomyopathy and suggest that rare TREs contribute to ∼4% of cardiomyopathy risk. FUNDING: Government of Ontario (RKCY), The Canadian Institutes of Health Research PJT 175329 (RKCY), The Azrieli Foundation (RKCY), SickKids Catalyst Scholar in Genetics (RKCY), The University of Toronto McLaughlin Centre (RKCY, SM), Ted Rogers Centre for Heart Research (SM), Data Sciences Institute at the University of Toronto (SM), The Canadian Institutes of Health Research PJT 175034 (SM), The Canadian Institutes of Health Research ENP 161429 under the frame of ERA PerMed (SM, RL), Heart and Stroke Foundation of Ontario & Robert M Freedom Chair in Cardiovascular Science (SM), Bitove Family Professorship of Adult Congenital Heart Disease (EO), Canada Foundation for Innovation (SWS, JR), Canada Research Chair (PS), Genome Canada (PS, JR), The Canadian Institutes of Health Research (PS).


Subject(s)
Cardiomyopathies , Heart Defects, Congenital , Humans , Adult , Heart Defects, Congenital/genetics , Tandem Repeat Sequences/genetics , DNA Methylation , Cardiomyopathies/genetics , Ontario , Nerve Tissue Proteins/genetics
13.
Psychol Sport Exerc ; 72: 102601, 2024 May.
Article in English | MEDLINE | ID: mdl-38278464

ABSTRACT

Different motor learning methods (explicit or analogy learning) show different effects on motor performance stability, and reinvestment propensity plays an important role in motor performance stability. This study aimed to explore whether reinvestment propensity, that is, movement self-consciousness (MS-C) and conscious motor processing (CMP) as two dimensions, played a moderating role in the relationship between motor learning methods and motor performance stability. A total of 78 participants were randomly assigned to either the explicit or analogy learning group and their reinvestment propensity was measured. We recorded the number of golf putt goals in both the practice phase and the test phases (including a retention test and a stress test). In the moderating analysis, participants' reinvestment propensity was the moderating variable, and the dependent variable was motor performance stability (i.e., the difference between the two test phases). Results showed that motor performance was significantly different between practicing blocks, which indicated that the motor performance of learners was gradually increasing. The significant interaction between learning methods and the test phase on motor performance was detected, suggesting under stress, analogy learning was more likely to maintain the stability of motor performance, while explicit learning impaired the stability of motor performance. The CMP played a significant moderating role in the relationship between motor learning methods and motor performance stability. The result indicated that for learners with low CMP, the motor performance stability of analogy learning was better than explicit learning, while there was no significant difference in the stability of motor performance between the two learning methods for learners with high reinvestment propensity. No significant evidence was found that MS-C played a moderating role in the relationship between motor learning methods and motor performance stability. These findings expand the theoretical framework of motor skill learning and provide theoretical support for motor performance stability.


Subject(s)
Golf , Motor Skills , Humans , Learning , Movement , Emotions
14.
Small ; 20(21): e2310117, 2024 May.
Article in English | MEDLINE | ID: mdl-38155494

ABSTRACT

Chemical mechanical polishing (CMP) offers a promising pathway to smooth third-generation semiconductors. However, it is still a challenge to reduce the use of additional oxidants or/and energy in current CMP processes. Here, a new and green atomically smoothing method: Piezocatalytic-CMP (Piezo-CMP) is reported. Investigation shows that the Piezo-CMP based on tetragonal BaTiO3 (t-BT) can polish the rough surface of a reaction sintering SiC (RS-SiC) to the ultra-smooth surface with an average surface roughness (Ra) of 0.45 nm and the rough surface of a single-crystal 4H-SiC to the atomic planarization Si and C surfaces with Ra of 0.120 and 0.157 nm, respectively. In these processes, t-BT plays a dual role of piezocatalyst and abrasive. That is, it piezo-catalytically generates in-situ active oxygen species to selectively oxidize protruding sites of SiC surface, yielding soft SiO2, and subsequently, it acts as a usual abrasive to mechanically remove these SiO2. This mechanism is further confirmed by density functional theory (DFT) calculation and molecular simulation. In this process, piezocatalytic oxidation is driven only by the original pressure and friction force of a conventional polishing process, thus, the piezo-CMP process do not require any additional oxidant and energy, being a green and effective polishing method.

15.
BMC Psychol ; 11(1): 435, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38066558

ABSTRACT

BACKGROUND: The Mental Health Quality of Life (MHQoL) questionnaire is concise and suitable for rapid assessment of CMP (chronic musculoskeletal pain) patients in primary care. However, there is a lack of Chinese versions of the MHQoL. OBJECTIVE: To cross-culturally translate the MHQoL into Chinese and to assess its psychometric properties in Chinese-speaking patients with CMP. METHODS: The MHQoL was translated into Chinese according to the International Guidelines for the Cross-Cultural Adaptation of Self-Report Measures. 171 CMP patients were recruited to receive the Chinese versions of the MHQoL, SF-36, and HADS tests, and the MHQoL was retested seven days later. RESULT: The Chinese version of MHQoL had good retest reliability (MHQoL-7D: ICC = 0.971; MHQoL-VAS: ICC = 0.988) and internal consistency (Cronbach's alpha = 0.829). It showed a moderate correlation with the SF-36 total score (r=-0.509); the MHQoL-VAS moderately correlated with the Hospital Anxiety Depression Scale (r=-0.548). The MHQoL-7D showed no correlations with the SF-36's PF (r=-0.083) and BP (r=-0.170), weak correlations with RP (r=-0.284), RE (r=-0.298), and SF (r=-0.380), and moderate-to-strong correlations with GH (r=-0.638), VT (r=-0.480), and MH (r=-0.632). CONCLUSION: The Chinese version of the MHQoL can be used in clinical practice and research in Chinese-speaking CMP patients.


Subject(s)
Musculoskeletal Pain , Quality of Life , Humans , Musculoskeletal Pain/diagnosis , Cross-Cultural Comparison , Mental Health , Reproducibility of Results , Surveys and Questionnaires , Psychometrics
16.
Microbiol Spectr ; 11(6): e0294423, 2023 Dec 12.
Article in English | MEDLINE | ID: mdl-37850751

ABSTRACT

IMPORTANCE: The Gram-negative coccobacillus Mannheimia haemolytica is a natural inhabitant of the upper respiratory tract in ruminants and the most common bacterial agent involved in bovine respiratory disease complex development. Key virulence factors harbored by M. haemolytica are leukotoxin, lipopolysaccharide, capsule, adhesins, and neuraminidase which are involved in evading innate and adaptive immune responses. In this study, we have shown that CMP-sialic acid synthetase (neuA) is necessary for the incorporation of sialic acid onto the membrane, and inactivation of neuA results in increased phagocytosis and complement-mediated killing of M. haemolytica, thus demonstrating that sialylation contributes to the virulence of M. haemolytica.


Subject(s)
Mannheimia haemolytica , Cattle , Animals , Mannheimia haemolytica/genetics , Mannheimia haemolytica/metabolism , N-Acylneuraminate Cytidylyltransferase/genetics , N-Acylneuraminate Cytidylyltransferase/metabolism , Serogroup , Gene Deletion , Phagocytosis
17.
Materials (Basel) ; 16(7)2023 Mar 23.
Article in English | MEDLINE | ID: mdl-37048844

ABSTRACT

Chemical-mechanical planarization (CMP) represents the preferred technology in which both chemical and mechanical interactions are combined to achieve global planarization/polishing of wafer surfaces (wafer patterns from metal with a selective layer, in this paper). CMP is a complex process of material removal process by friction, which interferes with numerous mechanical and chemical parameters. Compared with chemical parameters, mechanical parameters have a greater influence on the material removal rate (MRR). The mechanical parameters manifest by friction force (Ff) and heat generated by friction in the CMP process. The Ff can be estimated by its monitoring in the CMP process, and process temperature is obtained with help of an infrared rays (IR) sensor. Both the Ff and the MRR increase by introducing colloidal silica (SiO2) as an abrasive into the selective layer CMP slurry. The calculated wafer non-uniformity (WNU) was correlated with the friction coefficient (COF). The control of Ff and of the slurry stability is important to maintain a good quality of planarization with optimal results, because Ff participates in mechanical abrasion, and large Ff may generate defects on the wafer surface. Additionally, the temperature generated by the Ff increases as the SiO2 concentration increases. The MRR of the selective layer into the CMP slurry showed a non-linear (Prestonian) behavior, useful not only to improve the planarization level but to improve its non-uniformity due to the various pressure distributions. The evaluation of the Ff allowed the calculation of the friction energy (Ef) to highlight the chemical contribution in selective-layer CMP, from which it derived an empirical model for the material removal amount (MRA) and validated by the CMP results. With the addition of abrasive nanoparticles into the CMP slurry, their concentration increased and the MRA of the selective layer improved; Ff and MRR can be increased due to the number of chemisorbed active abrasive nanoparticles by the selective layer. Therefore, a single abrasive was considered to better understand the effect of SiO2 concentration as an abrasive and of the MRR features depending on abrasive nanoparticle concentration. This paper highlights the correlation between friction and temperature of the SiO2 slurry with CMP results, useful to examine the temperature distribution. All the MRRs depending on Ef after planarization with various SiO2 concentrations had a non-linear characteristic. The obtained results can help in developing a CMP process more effectively.

18.
J Colloid Interface Sci ; 643: 465-479, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37088050

ABSTRACT

The cleaning solution for the post-chemical mechanical planarization (post-CMP) process of tungsten in neutral-alkaline media requires corrosion inhibitors as an additive, especially for advanced devices where the device node size shrinks below 10 nm. In the present study, the corrosion inhibition performance of benzethonium chloride (BTC) is evaluated in neutral-alkaline conditions. The electrochemical impedance spectroscopy (EIS) analysis showed âˆ¼ 90 % of corrosion inhibition efficiency with an optimum concentration of 0.01 wt% BTC at both pH 7 and 11. Langmuir adsorption isotherm, frontier molecular orbital theory, molecular simulation, contact angle, precipitation study, and X-ray photoelectron spectroscopy analysis were performed to identify the inhibition mechanism of the BTC molecule on the W surface. Based on the proposed mechanism, the electrostatic attraction between the positively charged N atom in the BTC molecule and the negatively charged W surface initiates the adsorption of the molecule. The high dipole moment and large molecular size enhance the physical adsorption of the molecule to the surface. In addition to this, the adsorption isotherm analysis shows that possible chemical interaction with a moderate value of Gibbs free energy change of adsorption exists between the W and BTC molecule. The excellent corrosion inhibition efficiency of BTC on W is confirmed by the frontier molecular orbital theory and molecular dynamic simulation analysis.

19.
Membranes (Basel) ; 13(3)2023 Feb 22.
Article in English | MEDLINE | ID: mdl-36984647

ABSTRACT

Progesterone (PRG) is a key cyclical reproductive hormone that has a significant impact on female organs in vertebrates. It is mainly produced by the corpus luteum of the ovaries, but can also be generated from other sources such as the adrenal cortex, Leydig cells of the testes and neuronal and glial cells. PRG has wide-ranging physiological effects, including impacts on metabolic systems, central nervous systems and reproductive systems in both genders. It was first purified as an ovarian steroid with hormonal function for pregnancy, and is known to play a role in pro-gestational proliferation during pregnancy. The main function of PRG is exerted through its binding to progesterone receptors (nPRs, mPRs/PAQRs) to evoke cellular responses through genomic or non-genomic signaling cascades. Most of the existing research on PRG focuses on classic PRG-nPR-paired actions such as nuclear transcriptional factors, but new evidence suggests that PRG also exerts a wide range of PRG actions through non-classic membrane PRG receptors, which can be divided into two sub-classes: mPRs/PAQRs and PGRMCs. The review will concentrate on recently found non-classical membrane progesterone receptors (mainly mPRs/PAQRs) and speculate their connections, utilizing the present comprehension of progesterone receptors.

20.
Biosensors (Basel) ; 13(3)2023 Feb 22.
Article in English | MEDLINE | ID: mdl-36979520

ABSTRACT

Dopamine (DA), an organic biomolecule that acts as both a hormone and a neurotransmitter, is essential in regulating emotions and metabolism in living organisms. The accurate determination of DA is important because it indicates early signs of serious neurological disorders. Covalent organic frameworks (COFs) and metal-organic frameworks (MOFs) have received considerable attention in recent years as promising porous materials with an unrivaled degree of tunability for electrochemical biosensing applications. This study adopted a solvothermal strategy for the synthesis of a conjugated microporous poly(arylene ethynylene)-4 (CMP-4) network using the Sonagashira-Hagihara cross-coupling reaction. To increase the crystallinity and electrical conductivity of the material, CMP-4 was enveloped around carbon nanotubes (CNTs), followed by iodine doping. When used as an electrochemical probe, the as-synthesized material (I2-CMP-CNT-4) exhibited excellent selectivity and sensitivity to dopamine in the phosphate-buffered solution. The detection limits of the electrochemical sensor were 1 and 1.7 µM based on cyclic voltammetry (CV) and differential pulse voltammetry (DPV).


Subject(s)
Metal-Organic Frameworks , Nanotubes, Carbon , Electrodes , Nanotubes, Carbon/chemistry , Dopamine , Electrochemical Techniques , Metal-Organic Frameworks/chemistry , Limit of Detection
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