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Fulltext Tuning the Magnetism in Boron-Doped Strontium Titanate

Zeng H, Wu M, Wang HQ, Zheng JC, Kang J

Materials (Basel), 2020 Dec 12;13(24).
PMID: 33322841 DOI: 10.3390/ma13245686

The magnetic and electronic properties of boron-doped SrTiO3 have been studied by first-principles calculations. We found that the magnetic ground states of B-doped SrTiO3 strongly depended on the dopant-dopant separation distance. As the dopant-dopant distance varied, the magnetic ground states of B-doped SrTiO3 can have nonmagnetic, ferromagnetic or antiferromagnetic alignment. The structure with the smallest dopant-dopant separation exhibited the lowest total energy among all configurations considered and was characterized by dimer pairs due to strong attraction. Ferromagnetic coupling was observed to be stronger when the two adjacent B atoms aligned linearly along the B-Ti-B axis, which could be associated with their local bonding structures. Therefore, the symmetry of the local structure made an important contribution to the generation of a magnetic moment. Our study also demonstrated that the O-Ti-O unit was easier than the Ti-B-Ti unit to deform. The electronic properties of boron-doped SrTiO3 tended to show semiconducting or insulating features when the dopant-dopant distance was less than 5 Å, which changed to metallic properties when the dopant-dopant distance was beyond 5 Å. Our calculated results indicated that it is possible to manipulate the magnetism and band gap via different dopant-dopant separations.
Fulltext A Study on Arrhythmia via ECG Signal Classification Using the Convolutional Neural Network

Wu M, Lu Y, Yang W, Wong SY

Front Comput Neurosci, 2020;14:564015.
PMID: 33469423 DOI: 10.3389/fncom.2020.564015

Cardiovascular diseases (CVDs) are the leading cause of death today. The current identification method of the diseases is analyzing the Electrocardiogram (ECG), which is a medical monitoring technology recording cardiac activity. Unfortunately, looking for experts to analyze a large amount of ECG data consumes too many medical resources. Therefore, the method of identifying ECG characteristics based on machine learning has gradually become prevalent. However, there are some drawbacks to these typical methods, requiring manual feature recognition, complex models, and long training time. This paper proposes a robust and efficient 12-layer deep one-dimensional convolutional neural network on classifying the five micro-classes of heartbeat types in the MIT- BIH Arrhythmia database. The five types of heartbeat features are classified, and wavelet self-adaptive threshold denoising method is used in the experiments. Compared with BP neural network, random forest, and other CNN networks, the results show that the model proposed in this paper has better performance in accuracy, sensitivity, robustness, and anti-noise capability. Its accurate classification effectively saves medical resources, which has a positive effect on clinical practice.
Fulltext Impulse buying behavior during livestreaming: Moderating effects of scarcity persuasion and price perception

Feng Z, Al Mamun A, Masukujjaman M, Wu M, Yang Q

Heliyon, 2024 Apr 15;10(7):e28347.
PMID: 38560201 DOI: 10.1016/j.heliyon.2024.e28347

This research aimed to identify the factors that influence impulse buying behavior during livestreaming and advance the existing literature based on a proposed conceptual framework grounded in the stimulus-organism-response (S-O-R) model. We also tested the moderating effects of price perception and scarcity persuasion. An online self-administered questionnaire was used to collect data from 837 Chinese participants aged over 18 years. The data were analyzed using partial least squares structural equation modeling using Smart-PLS version 4.0. The findings showed that susceptibility to social influence, impulse buying tendency, cognitive reactions, affective reactions, and the urge to buy impulsively are statistically significant predictors of impulse buying during livestreaming, with price perception and scarcity persuasion as moderators. The study expands the S-O-R model for livestreaming impulse buying in e-commerce context, highlighting its multifaceted nature and revealing the mediating role of Urge to Buy Impulsively in translating cognitive and emotional factors into impulse buying behavior. These insights offer practical guidance for marketers to design tailored strategies that leverage psychological triggers and external cues to enhance consumer engagement and encourage desired behaviors, ultimately leading to more effective marketing campaigns and improved consumer experiences.
Fulltext Building a green Belt and Road: A systematic review and comparative assessment of the Chinese and English-language literature

Teo HC, Campos-Arceiz A, Li BV, Wu M, Lechner AM

PLoS One, 2020;15(9):e0239009.
PMID: 32932516 DOI: 10.1371/journal.pone.0239009

International attention on the environmental impacts of China's Belt and Road Initiative (BRI) is increasing, but little is known internationally about the large corpus of Chinese BRI environmental research. We present the first systematic review of the Chinese and English-language BRI environmental research, supported with text mining and sentiment analysis. We found that the research is dominated by Chinese authors writing about BRI routes within China in Chinese, even though concerns around BRI are largely about impacts and benefits within host countries, and the volume of publications in English is recently catching up. Different disciplines and methods are well-represented across languages, apart from specific types of Chinese social science papers. The sentiments of academic research are largely neutral and less polarised than media discourse. We recommend that scientists and practitioners should pay more attention to BRI environmental impacts in developing countries and proactively engage local voices.
High-sulfur capacity and regenerable Zn-based sorbents derived from layered double hydroxide for hot coal gas desulfurization

Wu M, Chang B, Lim TT, Oh WD, Lei J, Mi J

J Hazard Mater, 2018 Oct 15;360:391-401.
PMID: 30130697 DOI: 10.1016/j.jhazmat.2018.08.015

The Zn-Al mixed metal oxide (ZnAl-MMO) with a plate-like structure was derived from Zn-Al layered double hydroxide. The ZnAl-MMO with a Zn/Al molar ratio of 3:1 exhibits superior absorption ability for H2S in a simulated coal gas at 600 ℃ due to the special structure of the ZnAl-MMO. Besides ZnS, elemental sulfur is also produced during the desulfurization process. The deactivation model could well simulate the absorption behavior of H2S. The sulfidation reaction over the sorbent shows large initial reaction rate constants (1110-5390 m3 min-1 kg-1) and low activation energy (29.5 kJ mol-1). The regeneration rate of the used sorbent can reach 99.8% under the optimum conditions. The regenerated sorbents still show high sulfur capacity (ca. 30%), implying its great application potential for industrial-scale desulfurization of the hot coal gas.
Fulltext Vinyl chloride accident unleashes a toxic legacy

Li C, Gao P, Yu R, Zhong H, Wu M, Lam SS, et al.

Environ Sci Ecotechnol, 2023 Apr;14:100259.
PMID: 36949895 DOI: 10.1016/j.ese.2023.100259
Modeling the significance of green orientation and culture on green innovation performance: moderating effect of firm size and green implementation

Bhatti SM, Al Mamun A, Wu M, Naznen F, Kanwal S, Makhbul ZKM

Environ Sci Pollut Res Int, 2023 Sep;30(44):99855-99874.
PMID: 37615918 DOI: 10.1007/s11356-023-29353-4

The current global trend in sustainable business practices is to optimize green innovation performance. To protect the environment and maintain their own survival, organizations must strengthen their green innovation capabilities. Drawing on the recourse-based view and ecology modernization theory (EMT), this study examines the direct effect of green strategic orientations, green entrepreneurial orientation, green market orientation, green innovation orientation, and green organizational culture on the firm's green innovation capability, as well as the mediating effect of green innovation capability on the relationship of these four factors and green innovation performance. Besides, this study also explored the moderating effects of green management system implementation and firm size on the association between green innovation capability and green innovation performance. To test the hypothesized model, a questionnaire survey was administered to gather responses from 293 medium-sized and large manufacturing firms operating in Pakistan. The partial least squares method was used for data analysis. The results revealed that green entrepreneurial orientation, green market orientation, green innovation orientation, and green organizational culture positively impacted green innovation capability, which subsequently positively influenced green innovation performance. Moreover, effective implementation of green management systems can bolster the effect of green innovation capability on green innovation performance, and the mediating effect of green innovation capability has also been confirmed. These indicated that the management of medium and large manufacturing firms operating in Pakistan should focus on encouraging green innovation and training employees regarding the latest eco-friendly technologies to attain performance and sustainable development goals. Policymakers should implement green business development programs and offer rewards or penalties for promoting compliance. The present study contributes greatly to the literature by applying EMT as an alternative to address the mediating role of green innovation capability and the moderating effect of green management system implementation in enhancing firms' green innovation performance.
Fulltext Modeling the intention and donation of second-hand clothing in the context of an emerging economy

Wu M, Al Mamun A, Yang Q, Gao J, Rahman MK, Al Shami SSA

Sci Rep, 2023 Sep 13;13(1):15106.
PMID: 37704693 DOI: 10.1038/s41598-023-42437-y

The culture of fast fashion accelerates the consumption rate of individuals but at the expense of significant environmental stress. With a large amount of discarded clothing accumulating in landfills, it is crucial to encourage people to dispose of second-hand clothing (SHC) as sustainably as possible, especially in an emerging economy with large volume consumption. Through a survey of 619 respondents from China, this study explored the factors affecting people's intentions and actual donation behaviors toward SHC. It extends the theory of interpersonal behavior (TIB) with environmental factors to construct a research framework, which included cognitive factors (attitude towards sustainable consumption), social factors (sense of community) and personal factors (perceived hedonic benefit) under TIB and the environment factors refers to problem awareness and ascription responsibility. Partial least squares structural equation modeling was employed to analyze the data. The findings revealed that attitudes toward sustainable consumption, problem awareness, ascription of responsibility, sense of community, and perceived hedonic benefit significantly and positively influenced people's intentions and practices of SHC donation. This study will aid governments and relevant green environmental protection organizations in formulating more precise strategies for sustainable development, and promote relevant research on the sustainable disposal of SHC.
Fulltext Predicting the intention and adoption of wearable payment devices using hybrid SEM-neural network analysis

Al Mamun A, Naznen F, Yang M, Yang Q, Wu M, Masukujjaman M

Sci Rep, 2023 Jul 11;13(1):11217.
PMID: 37433838 DOI: 10.1038/s41598-023-38333-0

This study aims to examine the mediating effect of the intention to use wearable payment devices (WPD) between perceived ease of use (PE), perceived usefulness (PU), social influence (SI), perceived trust (TR), and lifestyle compatibility (CM) on the adoption of WPD. Examination was made on the moderating effect of age and gender to improve the understanding of the adoption of WPD as a new payment system. Empirical data was collected through an online survey from 1094 respondents in Malaysia. Furthermore, this study employed dual-stage data analysis through partial least squares structural equation modelling (PLS-SEM) to test the causal and moderating effects, including artificial neural network (ANN) to examine the predictive power of the selected model. As a result, it was found that PE, PU, TR, and CM had a significant positive influence on the intention to use WPD. Furthermore, facilitating conditions and the intention to use WPD exhibited strong positive impacts on the adoption of WPD among Malaysian youth. The intention to use WPD positively and significantly mediated all predictors of adoption of WPD. Following that, ANN analysis confirmed high prediction accuracy of the data fitness. Overall, the findings for ANN highlighted the importance of PE, CM, and TR on the intention to adopt WPD and the impact of facilitating conditions on the adoption of WPD among Malaysian youth. Theoretically, the study extended UTAUT with two additional determinants (e.g., perceived trust and lifestyle compatibility), which were found to have significant influences on the intention to use WPD. The study results would be able to help payment service providers and the smart wearable device industry offer an innovative spectrum of products and present effective marketing tactics to encourage the prospective consumers of Wearable Payment Devices in Malaysia.
Fulltext Concomitant Ulnar Styloid Fractures in Distal Radius Osteosynthesis Does Not Impact Radiographic Outcomes, Ulnar Sided Symptoms and Patient Outcomes

Wong KC, Wu M, Zai Q, Wong MK, Howe TS, Koh S, et al.

Malays Orthop J, 2023 Mar;17(1):142-148.
PMID: 37064641 DOI: 10.5704/MOJ.2303.017

INTRODUCTION: Current literature reports varied significance of ulnar styloid fractures (USF) associated with distal radius fractures. Our study assesses the role of ulnar styloid fractures and fragment size in surgically managed distal radius fractures.
MATERIALS AND METHODS: We reviewed patients who underwent surgical fixation of distal radius fractures between January 2004 to June 2006. Patients were divided into those with (Group 1) and without (Group 0) USFs. Post-operative radiographic parameters, clinical outcomes and overall wrist function were analysed. Outcomes included ulnar-sided wrist pain, extensor carpi ulnaris (ECU) tendinitis, triangular fibrocartilage complex (TFCC) grind test, distal radioulnar joint (DRUJ) instability and pain. Overall wrist function was assessed with range of motion and Disabilities of the Arm, Shoulder and Hand (DASH) score.
RESULTS: Our study cohort included 31 males and 23 females, and 38.9% of these patients had concomitant USFs. There was no difference in terms of demographic data and fracture configuration between groups. Radiographic parameters were similar, except for palmar tilt, which was significantly higher in Group 1 (4.6º vs 9.4º, p=0.047). At 24 months, there were no differences in clinical outcomes and overall wrist function. A sub-group analysis showed that mean USF fragment size was larger in patients with a positive TFCC grind test (3.9mm vs 7.3mm, p=0.033).
CONCLUSION: The presence of USFs in surgically managed distal radius fractures does not compromise clinical and functional outcome. Similarly, the size of USFs does not impact clinical and functional outcome but is associated with the presence of a positive TFCC grind test.
Accurate wavelet thresholding method for ECG signals

Yu K, Feng L, Chen Y, Wu M, Zhang Y, Zhu P, et al.

Comput Biol Med, 2024 Feb;169:107835.
PMID: 38096762 DOI: 10.1016/j.compbiomed.2023.107835

Current wavelet thresholding methods for cardiogram signals captured by flexible wearable sensors face a challenge in achieving both accurate thresholding and real-time signal denoising. This paper proposes a real-time accurate thresholding method based on signal estimation, specifically the normalized ACF, as an alternative to traditional noise estimation without the need for parameter fine-tuning and extensive data training. This method is experimentally validated using a variety of electrocardiogram (ECG) signals from different databases, each containing specific types of noise such as additive white Gaussian (AWG) noise, baseline wander noise, electrode motion noise, and muscle artifact noise. Although this method only slightly outperforms other methods in removing AWG noise in ECG signals, it far outperforms conventional methods in removing other real noise. This is attributed to the method's ability to accurately distinguish not only AWG noise that is significantly different spectrum of the ECG signal, but also real noise with similar spectra. In contrast, the conventional methods are effective only for AWG noise. In additional, this method improves the denoising visualization of the measured ECG signals and can be used to optimize other parameters of other wavelet methods to enhancing the denoised periodic signals, thereby improving diagnostic accuracy.
Fulltext Protect the oceans from Japan's radioisotope dumping

Li C, Zhong H, Meng L, Wu M, Ning W, Lam SS, et al.

Environ Sci Ecotechnol, 2024 Jul;20:100369.
PMID: 38318213 DOI: 10.1016/j.ese.2023.100369

•Dumping of Fukushima's radioactive wastewater raises marine food web concern.•Tritium seems to be the most problematic compound.•Long-lived radioisotopes Biomagnify up to 50,000 folds in marine fish species.•This threatens fragile deep-sea ecosystems requiring immediate action.•Empowered Routine monitoring is crucial to maintain planetary health.
Fulltext Man-made reactive oxygen species as green disinfectants

Li C, Zhong H, Liu G, Liu D, Wu M, Lam SS, et al.

Eco Environ Health, 2023 Dec;2(4):243-245.
PMID: 38435354 DOI: 10.1016/j.eehl.2023.05.001

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Fulltext Modelling the significance of food delivery service quality on customer satisfaction and reuse intention

Wu M, Gao J, Hayat N, Long S, Yang Q, Al Mamun A

PLoS One, 2024;19(2):e0293914.
PMID: 38359026 DOI: 10.1371/journal.pone.0293914

The millions-worth revenue derived from large-scale food delivery characterises the service as a relatively established phenomenon with potential growth. The current cross-sectional research examined online food delivery service quality on consumer satisfaction and reuse intention. Service quality was divided into seven categories (i.e., reliability, assurance, security, maintaining food quality, system operation, traceability, and perceived service value). Perceived service value offer the unique understanding of the online food delivery consumer satisfaction. Empirical data were elicited from 1352 valid respondents and subsequently assessed through the partial least square structural equation modelling. Findings revealed that reliability, assurance, maintaining food quality, system operation, traceability, and perceived service value could elevate customer satisfaction and optimize the intention to reuse food delivery services. Specific measures to improve service quality, including staff training, improved after-sales service, and system optimisation, were proposed to increase users' satisfaction and intention to reuse optimally.
Sub-5 nm Ultra-Fine FeP Nanodots as Efficient Co-Catalysts Modified Porous g-C3N4 for Precious-Metal-Free Photocatalytic Hydrogen Evolution under Visible Light

Zeng D, Zhou T, Ong WJ, Wu M, Duan X, Xu W, et al.

ACS Appl Mater Interfaces, 2019 Feb 13;11(6):5651-5660.
PMID: 30615433 DOI: 10.1021/acsami.8b20958

Sub-5 nm ultra-fine iron phosphide (FeP) nano-dots-modified porous graphitic carbon nitride (g-C3N4) heterojunction nanostructures are successfully prepared through the gas-phase phosphorization of Fe3O4/g-C3N4 nanocomposites. The incorporation of zero-dimensional (0D) ultra-small FeP nanodots co-catalysts not only effectively facilitate charge separation but also serve as reaction active sites for hydrogen (H2) evolution. Herein, the strongly coupled FeP/g-C3N4 hybrid systems are employed as precious-metal-free photocatalysts for H2 production under visible-light irradiation. The optimized FeP/g-C3N4 sample displays a maximum H2 evolution rate of 177.9 μmol h-1 g-1 with the apparent quantum yield of 1.57% at 420 nm. Furthermore, the mechanism of photocatalytic H2 evolution using 0D/2D FeP/g-C3N4 heterojunction interfaces is systematically corroborated by steady-state photoluminescence (PL), time-resolved PL spectroscopy, and photoelectrochemical results. Additionally, an increased donor density in FeP/g-C3N4 is evidenced from the Mott-Schottky analysis in comparison with that of parent g-C3N4, signifying the enhancement of electrical conductivity and charge transport owing to the emerging role of FeP. The density functional theory calculations reveal that the FeP/g-C3N4 hybrids could act as a promising catalyst for the H2 evolution reaction. Overall, this work not only paves a new path in the engineering of monodispersed FeP-decorated g-C3N4 0D/2D robust nanoarchitectures but also elucidates potential insights for the utilization of noble-metal-free FeP nanodots as remarkable co-catalysts for superior photocatalytic H2 evolution.
Fulltext Genetic Identification of Edible Bird's Nest in Thailand Based on ARMS-PCR

Lv D, Fan Y, Zhong W, Lonan P, Liu K, Wu M, et al.

Front Genet, 2021;12:632232.
PMID: 33763113 DOI: 10.3389/fgene.2021.632232

Edible bird's nest (EBN) is a popular delicacy in the Asian Pacific region originating from Indonesia, Malaysia, Thailand and Vietnam, which consist of various potential medicine value in Traditional Chinese Medicine (TCM). Thailand is one of the main exporters of EBN. However, the genetic information of EBN, a key part of molecular biology, has yet to be reported in Thailand. It is necessary to explore the genetic information of EBN in Thailand based on a quick and simple method to help protect the rights and interests of consumers. This research aimed to systematically evaluate different methods of extracting EBN DNA to improve the efficiency of the analysis of cytochrome b (Cytb) and NADH dehydrogenase subunit 2 (ND2) gene sequences, the establishment of phylogenetic trees, and the genetic information of EBN in Thailand. Additionally, we aimed to develop a quick and simple method for identifying EBN from different species based on the genetic information and amplification-refractory mutation system PCR (ARMS-PCR). By comparing the four methods [cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), kit and guanidinium isothiocyanate methods] for EBN extraction, we found that the guanidinium isothiocyanate method was the optimal extraction method. Phylogenetic trees generated on the basis of Cytb and ND2 gene analyses showed that 26 samples of house EBN and 4 samples of cave EBN came from Aerodramus fuciphagus and Aerodramus maximus, respectively. In addition, to distinguish different samples from different species of Apodiformes, we designed 4 polymerase chain reaction (PCR) amplification primers based on the ND2 gene sequences of A. fuciphagus and A. maximus. The ARMS-PCR results showed band lengths for A. fuciphagus EBN of 533, 402, and 201 bp, while those for A. maximus EBN were 463, 317, and 201 bp. Collectively, the results showed that ARMS-PCR is a fast and simple method for the genetic identification of EBN based on designing specific original identification primers.
Impact of dehydroepianrosterone (DHEA) supplementation on serum levels of insulin-like growth factor 1 (IGF-1): A dose-response meta-analysis of randomized controlled trials

Xie M, Zhong Y, Xue Q, Wu M, Deng X, O Santos H, et al.

Exp Gerontol, 2020 07 15;136:110949.
PMID: 32304719 DOI: 10.1016/j.exger.2020.110949

BACKGROUND AND AIM: Inconsistencies exist with regard to the influence of dehydroepiandrosterone (DHEA) supplementation on insulin-like growth factor 1 (IGF-1) levels. The inconsistencies could be attributed to several factors, such as dosage, gender, and duration of intervention, among others. To address these inconsistencies, we conducted a systematic review and meta-analysis to combine findings from randomized controlled trials (RCTs) on this topic.
METHODS: Electronic databases (Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar) were searched for relevant literature published up to February 2020.
RESULTS: Twenty-four qualified trials were included in this meta-analysis. It was found that serum IGF-1 levels were significantly increased in the DHEA group compared to the control (weighted mean differences (WMD): 16.36 ng/ml, 95% CI: 8.99, 23.74; p = .000). Subgroup analysis revealed that a statistically significant increase in serum IGF-1 levels was found only in women (WMD: 23.30 ng/ml, 95% CI: 13.75, 32.87); in participants who supplemented 50 mg/d DHEA (WMD: 15.75 ng/ml, 95% CI: 7.61, 23.89); in participants undergoing DHEA intervention for >12 weeks (WMD: 17.2 ng/ml, 95% CI: 8.02, 26.22); in participants without an underlying comorbidity (WMD: 19.11 ng/ml, 95% CI: 10.69, 27.53); and in participants over the age of 60 years (WMD: 19.79 ng/ml, 95% CI: 9.86, 29.72).
CONCLUSION: DHEA supplementation may increase serum IGF-I levels especially in women and older subjects. However, further studies are warranted before DHEA can be recommended for clinical use.
Construction of Cu7 S4 @CuCo2 O4 Yolk-Shell Microspheres Composite and Elucidation of Its Enhanced Photocatalytic Activity, Mechanism, and Pathway for Carbamazepine Degradation

He Z, Yang H, Wong NH, Ernawati L, Sunarso J, Huang Z, et al.

Small, 2023 Feb 10.
PMID: 36765447 DOI: 10.1002/smll.202207370

Water pollution caused by the massive use of medicines has caused significant environmental problems. This work first reports the synthesis and characterization of the Cu7 S4 /CuCo2 O4 (CS/CCO) yolk-shell microspheres via hydrothermal and annealing methods, and then investigates their photocatalytic performance in removing organic water pollutants. The 10-CS/CCO composite with yolk-shell microspheres exhibits the highest photodegradation rate of carbamazepine (CBZ), reaching 96.3% within 2 h. The 10-CS/CCO also demonstrates more than two times higher photodegradation rates than the pure (Cu7 S4 ) CS and (CuCo2 O4 ) CCO. This outstanding photocatalytic performance can be attributed to the unique yolk-shell structure and the Z-scheme charge transfer pathway, reducing multiple reflections of the acting light. These factors enhance the light absorption efficiency and efficiently transfer photoexcited charge carriers. In-depth, photocatalytic degradation pathways of CBZ are systematically evaluated via the identification of degradation intermediates with Fukui index calculation. The insights gained from this work can serve as a guideline for developing low-cost and efficient Z-scheme photocatalyst composites with the yolk-shell structure.
Postmenopausal hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease: A systematic review and time-response meta-analysis

Wu M, Li M, Yuan J, Liang S, Chen Z, Ye M, et al.

Pharmacol Res, 2020 05;155:104693.
PMID: 32057896 DOI: 10.1016/j.phrs.2020.104693

Hormone therapy continues to be a favourable option in the management of menopausal symptomatology, but the associated risk-benefit ratios with respect to neurodegenerative diseases remain controversial. The study aim was to determine the relation between menopausal hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease in human subjects. A literature search was performed in PubMed/Medline, Cochrane collaboration, and Scopus databases from onset of the database to September 2019. Random-effects model was used to estimate pooled odd ratio (OR) and 95 % confidence intervals (CI). Subgroup analysis was performed based on the type and formulation of hormone. In addition, the time-response effect of this relationship was also assessed based on duration of hormone therapy. Associations between hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease in menopausal women were reported in 28 studies. Pooled results with random effect model showed a significant association between hormone therapy and Alzheimer's disease (OR 1.08, 95 % CI 1.03-1.14, I2: 69 %). This relationship was more pronounced in patients receiving the combined estrogen-progestogen formulation. Moreover, a significant non-linear time-response association between hormone therapy and Alzheimer's disease was also identified (Coef1 = 0.0477, p1<0.001; Coef2 = -0.0932, p2<0.001). Similarly, pooled analysis revealed a significant association between hormone therapy and all-cause dementia (OR 1.16, 95 % CI 1.02-1.31, I2: 19 %). Interestingly, no comparable relationship was uncovered between hormone therapy as a whole and Parkinson's disease (OR 1.14, 95 % CI 0.95-1.38, I2: 65 %); however, sub-group analysis revealed a significant relationship between the disease and progestogen (OR 3.41, 95 % CI 1.23-9.46) or combined estrogen-progestogen formulation use (OR 1.49, 95 % CI 1.34-1.65). Indeed, this association was also found to be driven by duration of exposure (Coef1 = 0.0626, p1 = 0.04). This study reveals a significant direct relationship between the use of certain hormonal therapies and Alzheimer's disease, all-cause dementia, and Parkinson's disease in menopausal women. However, the association appears to shift in direct after five years in the context of Alzheimer's disease, adding further weight to the critical window or timing hypothesis of neurodegeneration and neuroprotection.
Electronic structure variations of polar and nonpolar ZnO lattices with nitrogen-ion bombardment using synchrotron-based in situ photoemission and X-ray absorption spectroscopy

Huang Y, Li Y, Wu M, Wang HQ, Yuan X, Gholam T, et al.

J Synchrotron Radiat, 2020 Jan 01;27(Pt 1):83-89.
PMID: 31868740 DOI: 10.1107/S160057751901381X

Surface polarity with different crystal orientations has been demonstrated as a crucial parameter in determining the physical properties and device applications in many transition metal oxide and semiconductor compound systems. The influences of surface polarity on electronic structures in nitrogen-incorporated ZnO lattices have been investigated in the present work. The successful doping of nitrogen atoms in ZnO lattices is suggested by the existence of N-related chemical bonds obtained from X-ray photoelectron spectroscopy analysis where a pronounced N-Zn peak intensity has been observed in the (000\bar 1)-terminated polar ZnO compound compared with the (10\bar 10)-terminated nonpolar ZnO compound. An energy shift of the valence band maximum towards the Fermi level has been resolved for both polar and nonpolar ZnO lattices, whereas a charge redistribution of the O 2p hybridized states is only resolved for o-plane ZnO with a polar surface. Angular-dependent X-ray absorption analyses at the O K-edge reveal enhanced surface-state contributions and asymmetric O 2p orbital occupations in the (000\bar 1)-terminated o-plane ZnO compound. The results shed light on the efficient nitrogen doping in ZnO lattices with polar surfaces. The comprehensive electronic structure investigations of correlations between impurity doping and surface polarity in ZnO lattices may also offer guidance for the material design in other transition metal oxide and semiconductor systems.

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