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Fulltext The effect of extrusion screw-speed on the water extractability and molecular weight distribution of arabinoxylans from defatted rice bran

Fadel A, Plunkett A, Ashworth J, Mahmoud AM, Ranneh Y, El Mohtadi M, et al.

J Food Sci Technol, 2018 Mar;55(3):1201-1206.
PMID: 29487463 DOI: 10.1007/s13197-017-3010-0

Arabinoxylans (AXs) are major dietary fibre in cereals. Recently, AXs have attracted a great deal of attention because of their biological activities. These activities have been suggested to be related to the content of low molecular weight (Mw) AXs, in particular those with Mw below 32 kDa. Rice bran is a rich source of AXs. However, water extraction of AXs is difficult and often gives low yield. Extrusion processing has been used to increase the solubility of cereal dietary fibre. The aim of this research was to study the effect of extrusion screw-speeds (80 and 160) rpm on the extraction yield and Mw of water extractable AXs from rice bran. It was found that the extraction of AXs increased significantly with an increase in screw speed and was accompanied by a significant decrease in the Mw of AXs from extruded rice bran. The percentage of very low molecular weight AXs (0.79-1.58 kDa) significantly increased with increasing screw speed.
Fulltext Investigating the Effect of COVID-19 on Driver Behavior and Road Safety: A Naturalistic Driving Study in Malaysia

Al-Hussein WA, Li W, Por LY, Ku CS, Alredany WHD, Leesri T, et al.

Int J Environ Res Public Health, 2022 Sep 07;19(18).
PMID: 36141497 DOI: 10.3390/ijerph191811224

The spread of the novel coronavirus COVID-19 resulted in unprecedented worldwide countermeasures such as lockdowns and suspensions of all retail, recreational, and religious activities for the majority of 2020. Nonetheless, no adequate scientific data have been provided thus far about the impact of COVID-19 on driving behavior and road safety, especially in Malaysia. This study examined the effect of COVID-19 on driving behavior using naturalistic driving data. This was accomplished by comparing the driving behaviors of the same drivers in three periods: before COVID-19 lockdown, during COVID-19 lockdown, and after COVID-19 lockdown. Thirty people were previously recruited in 2019 to drive an instrumental vehicle on a 25 km route while recording their driving data such as speed, acceleration, deceleration, distance to vehicle ahead, and steering. The data acquisition system incorporated various sensors such as an OBDII reader, a lidar, two ultrasonic sensors, an IMU, and a GPS. The same individuals were contacted again in 2020 to drive the same vehicle on the same route in order to capture their driving behavior during the COVID-19 lockdown. Participants were approached once again in 2022 to repeat the procedure in order to capture their driving behavior after the COVID-19 lockdown. Such valuable and trustworthy data enable the assessment of changes in driving behavior throughout the three time periods. Results showed that drivers committed more violations during the COVID-19 lockdown, with young drivers in particular being most affected by the traffic restrictions, driving significantly faster and performing more aggressive steering behaviors during the COVID-19 lockdown than any other time. Furthermore, the locations where the most speeding offenses were committed are highlighted in order to provide lawmakers with guidance on how to improve traffic safety in those areas, in addition to various recommendations on how to manage traffic during future lockdowns.
Why is tinnitus a problem? A large-scale qualitative evaluation of problems reported by tinnitus patients in mainland China

Hall DA, Xiong B, Li W, Wang Y, Zhang X, Zhao F

Int J Audiol, 2023 Apr 24.
PMID: 37093086 DOI: 10.1080/14992027.2023.2199441

Objectives: The lived experience of tinnitus has biopsychosocial characteristics which are influenced by sociocultural factors. The main purpose of this study is to investigate how tinnitus affects people in their everyday life in China. A deductive qualitative analysis examined whether an a priori Western-centric conceptual framework could extend to an Asian context.Design: A large-scale prospective survey collected patient-reported problems associated with tinnitus in 485 adults attending four major ENT clinics in Eastern and Southern mainland China.Results: The evidence suggests that patients in China express a narrower range of problem domains associated with the lived experience of tinnitus. While 13 tinnitus-related problem domains were confirmed, culture-specific adaptations included the addition uncomfortable (a novel concept not previously reported), and the potential exclusion of concepts such as intrusiveness, loss of control, loss of peace and loss of sense of self.Conclusions: The sociocultural context of patients across China plays an important role in defining the vocabulary used to describe the patient-centred impacts of tinnitus. Possible explanatory factors include cultural differences in the meaning and relevance of certain concepts relating to self and in help-seeking behaviour, low health literacy and a different lexicon in Chinese compared to English to describe tinnitus-related problems.
Fulltext Electroactive Biomaterials for Facilitating Bone Defect Repair under Pathological Conditions

Heng BC, Bai Y, Li X, Lim LW, Li W, Ge Z, et al.

Adv Sci (Weinh), 2023 Jan;10(2):e2204502.
PMID: 36453574 DOI: 10.1002/advs.202204502

Bone degeneration associated with various diseases is increasing due to rapid aging, sedentary lifestyles, and unhealthy diets. Living bone tissue has bioelectric properties critical to bone remodeling, and bone degeneration under various pathological conditions results in significant changes to these bioelectric properties. There is growing interest in utilizing biomimetic electroactive biomaterials that recapitulate the natural electrophysiological microenvironment of healthy bone tissue to promote bone repair. This review first summarizes the etiology of degenerative bone conditions associated with various diseases such as type II diabetes, osteoporosis, periodontitis, osteoarthritis, rheumatoid arthritis, osteomyelitis, and metastatic osteolysis. Next, the diverse array of natural and synthetic electroactive biomaterials with therapeutic potential are discussed. Putative mechanistic pathways by which electroactive biomaterials can mitigate bone degeneration are critically examined, including the enhancement of osteogenesis and angiogenesis, suppression of inflammation and osteoclastogenesis, as well as their anti-bacterial effects. Finally, the limited research on utilization of electroactive biomaterials in the treatment of bone degeneration associated with the aforementioned diseases are examined. Previous studies have mostly focused on using electroactive biomaterials to treat bone traumatic injuries. It is hoped that this review will encourage more research efforts on the use of electroactive biomaterials for treating degenerative bone conditions.
Fulltext Undergraduate Students' Profiles of Cognitive Load in Augmented Reality-Assisted Science Learning and Their Relation to Science Learning Self-efficacy and Behavior Patterns

Lin XF, Wong SY, Zhou W, Shen W, Li W, Tsai CC

Int J Sci Math Educ, 2023 May 04.
PMID: 37363784 DOI: 10.1007/s10763-023-10376-9

Research evidence indicated that a specific type of augmented reality-assisted (AR-assisted) science learning design or support might not suit or be effective for all students because students' cognitive load might differ according to their experiences and individual characteristics. Thus, this study aimed to identify undergraduate students' profiles of cognitive load in AR-assisted science learning and to examine the role of their distinct profiles in self-efficacy together with associated behavior patterns in science learning. After ensuring the validity and reliability of each measure, a latent profile analysis confirmed that 365 Chinese undergraduates carried diverse dimensions of cognitive load simultaneously. The latent profile analysis findings revealed four fundamental profiles: Low Engagement, Immersive, Dabbling, and Organized, characterized as carrying various respective cognitive loads. The multivariate analysis of variance findings revealed different levels of the six AR science learning self-efficacy dimensions across profiles. Low Engagement students displayed the lowest self-efficacy among all dimensions. Organized students recorded better conceptual understanding and higher-order cognitive skills than Dabbling ones. Students with the Immersive profile had the highest science learning self-efficacy. The lag sequential analysis results showed significant differences in behavior patterns among profiles. Among them, profiles with social interaction, test, and reviewing feedback behavior had a significantly higher score for self-efficacy than those patterns mainly based on test learning and resource visits. This finding provides a unified consideration of students' diverse profiles and can inform interventions for effective design of AR-assisted science learning to match appropriate strategies to facilitate the science learning effect.
Fulltext Design and implementation of adolescent health Latin dance teaching system under artificial intelligence technology

Liu X, Soh KG, Dev Omar Dev R, Li W, Yi Q

PLoS One, 2023;18(11):e0293313.
PMID: 37917594 DOI: 10.1371/journal.pone.0293313

Since various dance teaching systems have attracted much attention with the development of Artificial Intelligence (AI) technology, this paper improves the recognition performance of Latin dance teaching systems by optimizing the action recognition model. Firstly, the object detection and action recognition technology under the current AI technology is analyzed, and the Two-stage object detection algorithm and One-stage object detection algorithm are evaluated. Secondly, the technologies and functions contained in the adolescent health Latin dance teaching system are described, including image acquisition, feature extraction, object detection, and action recognition. Finally, the action recognition algorithm is optimized based on object detection, and the rationality and feasibility of the proposed algorithm are verified by experiments. The experimental results show that the optimization algorithm can search the optimal feature subset after five iterations on Undefine Classes of 101 (UCF101) dataset, but it needs seven iterations on Human Motion Database 51 (HMDB51) dataset. Meanwhile, when using support vector machine classifier, the optimization algorithm can achieve the highest accuracy of motion recognition. Regressive Function, Multinomial Naive Bayes and Gaussian Naive Bayes Algorithms have lower prediction delay, as low as 0.01s. Therefore, this paper has certain reference significance for the design and implementation of adolescent health Latin dance teaching system.
Psychrobacter species enrichment as potential microplastic degrader and the putative biodegradation mechanism in Shenzhen Bay sediment, China

Ou D, Ni Y, Li W, He W, Wang L, Huang H, et al.

J Hazard Mater, 2024 Feb 15;464:132971.
PMID: 37956562 DOI: 10.1016/j.jhazmat.2023.132971

Microplastic (MP) pollution has emerged as a pressing environmental concern due to its ubiquity and longevity. Biodegradation of MPs has garnered significant attention in combatting global MP contamination. This study focused on MPs within sediments near the sewage outlet of Shenzhen Bay. The objective was to elucidate the microbial communities in sediments with varying MPs, particularly those with high MP loads, and to identify microorganisms associated with MP degradation. The results revealed varying MP abundance, ranging from 211 to 4140 items kg-1 dry weight (d. w.), with the highest concentration observed near the outfall. Metagenomic analysis confirmed the enrichment of Psychrobacter species in sediments with high MP content. Psychrobacter accounted for ∼16.71% of the total bacterial community and 41.71% of hydrocarbon degrading bacteria at the S3 site, exhibiting a higher abundance than at other sampling sites. Psychrobacter contributed significantly to bacterial function at S3, as evidenced by the Kyoto Encyclopedia of Genes and Genomes pathway and enzyme analysis. Notably, 28 enzymes involved in MP biodegradation were identified, predominantly comprising oxidoreductases, hydrolases, transferases, ligases, lyases, and isomerases. We propose a putative mechanism for MP biodegradation, involving the breakdown of long-chain plastic polymers and subsequent oxidation of short-chain oligomers, ultimately leading to thorough mineralization.
Spatial-temporal pattern of change in production-living-ecological space of Nanchong City from 2000 to 2020 and underlying factors

Xu H, Zhang F, Li W, Shi J, Johnson BA, Tan ML

Environ Monit Assess, 2023 Dec 27;196(1):94.
PMID: 38150164 DOI: 10.1007/s10661-023-12249-8

This study analyzed the spatial-temporal change pattern and underlying factors in production-living-ecological space (PLES) of Nanchong City, China, over the past 20 years using historical land use data (2000, 2010, 2020). A land use transfer matrix was calculated from the historical land use maps, and spatial analysis was conducted to analyze changes in the land use dynamics degree, standard deviation ellipse, and center of gravity. The results showed that there was a rapid spatial evolution of the PLES in Nanchong from 2000 to 2010, followed by a stabilization in the second decade. The transfer of ecological-production space occurred mainly in the Jialing and Yilong River basins, while the reduction of production space and the increase of living space were most prominent in the intersection of three districts (Shunqing, Jialing, and Gaoping districts). The return of production-ecological space was observed in the south and northeast of Yingshan, and there was little notable transfer of other types. The distribution of production space in Nanchong evolved in a north-south to east-west trend, with the center of gravity moving from Yilong to Peng'an County. The living space and production space expanded in a north-south direction, and the center of gravity position was in Nanbu, indicating a more balanced growth or decrease in the last 20 years. The changes in the spatial-temporal pattern of PLES in Nanchong were attributed to the intertwined factors of national policies, economic development, population growth, and the natural environment. This study introduced a novel approach towards rational planning of land resources in Nanchong, which may facilitate more sustainable urban planning and development.
Fulltext The effects of musical feedback training on metacognition and self-directed learning

Li W, Manoharan P, Cui X, Liu F, Liu K, Dai L

Front Hum Neurosci, 2023;17:1304929.
PMID: 38173798 DOI: 10.3389/fnhum.2023.1304929

INTRODUCTION: Metacognition and self-directed learning are key components in educational research, recognized for their potential to enhance learning efficiency and problem-solving skills. This study explores the effects of musical feedback training on these competencies.
METHODS: The study involved 84 preservice teachers aged 18 to 21. Participants were randomly assigned to either an experimental group, which received musical feedback training, or a control group.
RESULTS: The findings indicate that musical feedback training effectively improved metacognitive abilities. However, its impact on the readiness for self-directed learning was inconclusive. A notable difference in metacognition and self-directed learning readiness was observed between the experimental and control groups during the session, indicating a significant interaction effect. Furthermore, a positive correlation was identified between metacognition and self-directed learning.
DISCUSSION: These results contribute to educational discourse by providing empirical evidence on the utility of musical feedback training in fostering metacognition. They also highlight the importance of consistent and long-term engagement in self-directed learning practices. The significance of these findings advocates for incorporating music feedback training into music education curricula to enhance metacognition and improve overall learning efficiency.
Curcumin inhibits prostate cancer by upregulating miR-483-3p and inhibiting UBE2C

Li W, Wang F, Wang X, Xu W, Liu F, Hu R, et al.

J Biochem Mol Toxicol, 2024 Feb;38(2):e23645.
PMID: 38348716 DOI: 10.1002/jbt.23645

Prostate cancer (PCa) is an extremely common genitourinary malignancy among elderly men. Many evidence have shown the efficacy of curcumin (CUR) in inhibiting the progression of PCa. However, the pharmacological function of CUR in PCa is still not quite clear. In this research, CUR was found to suppress the proliferation and enhance the apoptotic rate in in vitro PCa cell models in a dose- and time-dependent manner. In a xenograft animal model, the administration of CUR contributed to a significant decrease in the growth of the xenograft tumor induced by the transplanted PC-3 cells. Ubiquitin-conjugating enzyme E2 C is implicated in the modulation of multiple types of cancers. In humans, the expression levels of UBE2C are significantly higher in PCa versus benign prostatic hyperplasia. Treatment with CUR decreased the expression of UBE2C, whereas it increased miR-483-3p expression. In contrast with the control mice, the CUR-treated mice showed a significant reduction in UBE2C and Ki-67 in PCa cells. The capability of proliferation, migration, and invasion of PCa cells was inhibited by the knockdown of UBE2C mediated by siRNA. Furthermore, dual luciferase reporter gene assay indicated the binding of miR-483-3p to UBE2C. In summary, CUR exerts its antitumor effects through regulation of the miR-483-3p/UBE2C axis by decreasing UBE2C and increasing miR-483-3p. The findings may also provide new molecular markers for PCa diagnosis and treatment.
Virulence, Host-Selective Toxin Production, and Development of Three Cochliobolus Phytopathogens Lacking the Sfp-Type 4'-Phosphopantetheinyl Transferase Ppt1

Zainudin NA, Condon B, De Bruyne L, Van Poucke C, Bi Q, Li W, et al.

Mol Plant Microbe Interact, 2015 Oct;28(10):1130-41.
PMID: 26168137 DOI: 10.1094/MPMI-03-15-0068-R

The Sfp-type 4'-phosphopantetheinyl transferase Ppt1 is required for activation of nonribosomal peptide synthetases, including α-aminoadipate reductase (AAR) for lysine biosynthesis and polyketide synthases, enzymes that biosynthesize peptide and polyketide secondary metabolites, respectively. Deletion of the PPT1 gene, from the maize pathogen Cochliobolus heterostrophus and the rice pathogen Cochliobolus miyabeanus, yielded strains that were significantly reduced in virulence to their hosts. In addition, ppt1 mutants of C. heterostrophus race T and Cochliobolus victoriae were unable to biosynthesize the host-selective toxins (HST) T-toxin and victorin, respectively, as judged by bioassays. Interestingly, ppt1 mutants of C. miyabeanus were shown to produce tenfold higher levels of the sesterterpene-type non-HST ophiobolin A, as compared with the wild-type strain. The ppt1 strains of all species were also reduced in tolerance to oxidative stress and iron depletion; both phenotypes are associated with inability to produce extracellular siderophores biosynthesized by the nonribosomal peptide synthetase Nps6. Colony surfaces were hydrophilic, a trait previously associated with absence of C. heterostrophus Nps4. Mutants were decreased in asexual sporulation and C. heterostrophus strains were female-sterile in sexual crosses; the latter phenotype was observed previously with mutants lacking Nps2, which produces an intracellular siderophore. As expected, mutants were albino, since they cannot produce the polyketide melanin and were auxotrophic for lysine because they lack an AAR.
Influence of Scanning on Nano Crystalline β-Ti Alloys Fabricated by Selective Laser Melting and Their Applications in Biomedical Science

Yan L, Yu J, Zhong Y, Gu Y, Ma Y, Li W, et al.

J Nanosci Nanotechnol, 2020 03 01;20(3):1605-1612.
PMID: 31492322 DOI: 10.1166/jnn.2020.17340

The present study focuses on the microstructural and bioactive properties evolution in selective laser melting (SLM) β titanium alloys. We have applied cross-scan strategy for improving mechanical properties and lower elastic modulus of SLMed Ti-20Mg-5Ta alloys which has been shown to be altering the microstructure and refining the grain size. The cross-scan strategy can refine the microstructure and induce various deformation textures in contrast to the conventional scan strategy. The microstructures of Ti-20Mg-5Ta alloys indicate that the cross-scan strategy will yield the best mechanical properties and lower elastic modulus. The corrosion behavior of the Ti-20Mg-5Ta alloys was studied during immersion in an acellular simulated body fluid (SBF) at 37±0.50 °C for 28 days. Both the mechanical and bioactive properties showed that the novel Ti-20Mg-5Ta alloys should be ideal for bone implants.
Fulltext Kawasaki Disease with Hepatobiliary Manifestations

Suhaini SA, Azidin AH, Cheah CS, Lee Wei Li W, Khoo MS, Ismail NAS, et al.

Medicina (Kaunas), 2022 Dec 12;58(12).
PMID: 36557034 DOI: 10.3390/medicina58121833

Background and Objectives: Kawasaki Disease (KD) incidence has been on the rise globally throughout the years, particularly in the Asia Pacific region. KD can be diagnosed based on several clinical criteria. Due to its systemic inflammatory nature, multi-organ involvement has been observed, making the diagnosis of KD more challenging. Notably, several studies have reported KD patients presenting with hepatobiliary abnormalities. Nonetheless, comprehensive data regarding the hepatobiliary manifestations of KD are limited in Malaysia, justifying a more in-depth study of the disease in this country. Thus, in this article, we aim to discuss KD patients in Malaysia with hepatobiliary manifestations. Materials and Methods: A total of six KD patients with hepatobiliary findings who presented at Hospital Canselor Tuanku Muhriz (HCTM) from 2004 to 2021 were selected and included. Variables including the initial presenting signs and symptoms, clinical progress, laboratory investigations such as liver function test (LFT), and ultrasound findings of hepatobiliary system were reviewed and analyzed. Results: Out of these six KD patients, there were two patients complicated with hepatitis and one patient with gallbladder hydrops. Different clinical features including jaundice (n = 3) and hepatomegaly (n = 4) were also observed. All patients received both aspirin and intravenous immunoglobulin (IVIG) as their first-line treatment and all of them responded well to IVIG. The majority of them (n = 5) had a complete recovery and did not have any cardiovascular and hepatobiliary sequelae. Conclusions: Despite KD mostly being diagnosed with the classical clinical criteria, patients with atypical presentations should always alert physicians of KD as one of the possible differential diagnoses. This study discovered that hepatobiliary manifestations in KD patients were not uncommon. More awareness on the epidemiology, diagnosis, and management of KD patients with hepatobiliary manifestations are required to allow for the initiation of prompt treatment, thus preventing further complications.
Fulltext A retrospective analysis of the care cascades for non-communicable disease and mental health among people living with HIV at a tertiary-care centre in Malaysia: opportunities to identify gaps and optimize care

Meng Li C, Jie Ying F, Raj D, Pui Li W, Kukreja A, Omar SF, et al.

J Int AIDS Soc, 2020 Nov;23(11):e25638.
PMID: 33206473 DOI: 10.1002/jia2.25638

INTRODUCTION: The rapidly growing epidemic of non-communicable diseases (NCDs) including mental health among aging people living with HIV (PLWH) has put a significant strain on the provision of health services in many HIV clinics globally. We constructed care cascades for specific NCDs and mental health among PLWH attending our centre to identify potential areas for programmatic improvement.
METHODS: This was a follow-up study of participants recruited in the Malaysian HIV & Aging study (MHIVA) from 2014 to 2016 at the University Malaya Medical Centre (n = 336). PLWH on suppressive antiretroviral therapy (ART) for a minimum of 12 months were invited to participate. At study entry, all participants underwent screening for diabetes (DM), hypertension (HTN) and dyslipidaemia; and completed assessments using the depression, anxiety and stress scale (DASS-21). Screening results were recorded in medical charts and clinical management provided as per standard of care. A subsequent review of medical records was performed at 24 months following study completion among participants who remained on active follow-up. Treatment pathways for NCD treatment and psychiatric referrals were assessed based on local practice guidelines to construct the care cascade.
RESULTS: A total of 329 participants (median age = 43 years, 83% male, 100% on ART) completed follow-up at 24 months. The prevalence of diabetes was 13%, dyslipidaemia 88% and hypertension 44%, whereas 23% presented with severe/extremely severe symptoms of depression, anxiety and/or stress. More than 50% of participants with dyslipidaemia and hypertension were not diagnosed until study screening, whereas over 80% with prevalent psychiatric symptoms were not previously recognized clinically. Suboptimal control of fasting lipids, sugar and blood pressure were found in the majority of participants despite optimal HIV treatment outcomes maintained over this same period. Only 32% of participants with severe/extremely severe mental health symptoms received psychiatric referrals and 83% of these attended their psychiatry clinic appointments.
CONCLUSIONS: Systematic screening must be introduced to identify NCDs and mental health issues among PLWH followed by proper linkage and referrals for management of screen-positive cases. Assessment of factors associated with attrition at each step of the care cascade is critically needed to improve health outcomes in our aging patients.
Fulltext Rh proteins and H+ transporters involved in ammonia excretion in Amur Ide (Leuciscus waleckii) under high alkali exposure

Zhao XF, Huang J, Li W, Wang SY, Liang LQ, Zhang LM, et al.

Ecotoxicol Environ Saf, 2024 Mar 15;273:116160.
PMID: 38432157 DOI: 10.1016/j.ecoenv.2024.116160

High alkaline environment can lead to respiratory alkalosis and ammonia toxification to freshwater fish. However, the Amur ide (Leuciscus waleckii), which inhabits an extremely alkaline lake in China with titratable alkalinity up to 53.57 mM (pH 9.6) has developed special physiological and molecular mechanisms to adapt to such an environment. Nevertheless, how the Amur ide can maintain acid-base balance and perform ammonia detoxification effectively remains unclear. Therefore, this study was designed to study the ammonia excretion rate (Tamm), total nitrogen accumulation in blood and tissues, including identification, expression, and localization of ammonia-related transporters in gills of both the alkali and freshwater forms of the Amur ide. The results showed that the freshwater form Amur ide does not have a perfect ammonia excretion mechanism exposed to high-alkaline condition. Nevertheless, the alkali form of Amur ide was able to excrete ammonia better than freshwater from Amur ide, which was facilitated by the ionocytes transporters (Rhbg, Rhcg1, Na+/H+ exchanger 2 (NHE2), and V-type H+ ATPase (VHA)) in the gills. Converting ammonia into urea served as an ammonia detoxication strategy to reduced endogenous ammonia accumulation under high-alkaline environment.
Intellectual and physical activities, but not social activities, are associated with better global cognition: a multi-site evaluation of the cognition and lifestyle activity study for seniors in Asia (CLASSA)

Lam LC, Ong PA, Dikot Y, Sofiatin Y, Wang H, Zhao M, et al.

Age Ageing, 2015 Sep;44(5):835-40.
PMID: 26271049 DOI: 10.1093/ageing/afv099

population ageing will lead to a leap in the dementia population in Asia. However, information about potentials for low-cost and low-risk interventions is limited.
Free Radical Generation from High-Frequency Electromechanical Dissociation of Pure Water

Rezk AR, Ahmed H, Brain TL, Castro JO, Tan MK, Langley J, et al.

J Phys Chem Lett, 2020 Jun 18;11(12):4655-4661.
PMID: 32453583 DOI: 10.1021/acs.jpclett.0c01227

We reveal a unique mechanism by which pure water can be dissociated to form free radicals without requiring catalysts, electrolytes, or electrode contact by means of high-frequency nanometer-amplitude electromechanical surface vibrations in the form of surface acoustic waves (SAWs) generated on a piezoelectric substrate. The physical undulations associated with these mechanical waves, in concert with the evanescent electric field arising from the piezoelectric coupling, constitute half-wavelength "nanoelectrochemical cells" in which liquid is trapped within the SAW potential minima with vertical dimensions defined by the wave amplitude (∼10 nm), thereby forming highly confined polarized regions with intense electric field strengths that enable the breakdown of water. The ions and free radicals that are generated rapidly electromigrate under the high field intensity in addition to being convectively transported away from the cells by the bulk liquid recirculation generated by the acoustic excitation, thereby overcoming mass transport limitations that lead to ion recombination.
Fulltext Agarose-resolvable InDel markers based on whole genome re-sequencing in cucumber

Adedze YMN, Lu X, Xia Y, Sun Q, Nchongboh CG, Alam MA, et al.

Sci Rep, 2021 02 16;11(1):3872.
PMID: 33594240 DOI: 10.1038/s41598-021-83313-x

Insertion and Deletion (InDel) are common features in genomes and are associated with genetic variation. The whole-genome re-sequencing data from two parents (X1 and X2) of the elite cucumber (Cucumis sativus) hybrid variety Lvmei No.1 was used for genome-wide InDel polymorphisms analysis. Obtained sequence reads were mapped to the genome reference sequence of Chinese fresh market type inbred line '9930' and gaps conforming to InDel were pinpointed. Further, the level of cross-parents polymorphism among five pairs of cucumber breeding parents and their corresponding hybrid varieties were used for evaluating hybrid seeds purity test efficiency of InDel markers. A panel of 48 cucumber breeding lines was utilized for PCR amplification versatility and phylogenetic analysis of these markers. In total, 10,470 candidate InDel markers were identified for X1 and X2. Among these, 385 markers with more than 30 nucleotide difference were arbitrary chosen. These markers were selected for experimental resolvability through electrophoresis on an Agarose gel. Two hundred and eleven (211) accounting for 54.81% of markers could be validated as single and clear polymorphic pattern while 174 (45.19%) showed unclear or monomorphic genetic bands between X1 and X2. Cross-parents polymorphism evaluation recorded 68 (32.23%) of these markers, which were designated as cross-parents transferable (CPT) InDel markers. Interestingly, the marker InDel114 presented experimental transferability between cucumber and melon. A panel of 48 cucumber breeding lines including parents of Lvmei No. 1 subjected to PCR amplification versatility using CPT InDel markers successfully clustered them into fruit and common cucumber varieties based on phylogenetic analysis. It is worth noting that 16 of these markers were predominately associated to enzymatic activities in cucumber. These agarose-based InDel markers could constitute a valuable resource for hybrid seeds purity testing, germplasm classification and marker-assisted breeding in cucumber.
Circulating miR-3197 and miR-2116-5p as novel biomarkers for diabetic retinopathy

Ji H, Yi Q, Chen L, Wong L, Liu Y, Xu G, et al.

Clin Chim Acta, 2020 Feb;501:147-153.
PMID: 31678272 DOI: 10.1016/j.cca.2019.10.036

Diabetic retinopathy (DR) is the leading cause of vision loss among older adults. The goal of this case-control study was to identify circulating miRNAs for the diagnosis of DR. The miRNeasy Serum/Plasma Kit was used to extract serum miRNAs. The μParaflo™ MicroRNA microarray was used to detect the expression levels of the miRNAs. The miRWalk algorithm was applied to predict the target genes of the miRNAs, which were further confirmed by the dual luciferase reporter gene system in HEK293T cells. A microarray was performed between 5 DR cases and 5 age-, sex-, body mass index-, and duration of diabetes-matched type 2 diabetic (T2DM) controls. The quantitative reverse transcription polymerase chain reaction technique was used to validate the differentially expressed circulating miRNAs in 45 DR cases and 45 well-matched controls. Receiver operating characteristic (ROC) curve analysis was used to evaluate the performance of the circulating miRNAs as diagnostic biomarkers for DR. Our microarray analysis screened out miR-2116-5p and miR-3197 as significantly up-regulated in DR cases compared with the controls. Furthermore, two miRNAs were validated in the 45 DR cases and 45 controls. The ROC analysis suggested that both miR-3197 and miR-2116-5p distinguished DR cases from controls. An additional dual-luciferase reporter gene assay confirmed that notch homolog 2 (NOTCH2) was the target gene of miR-2116-5p. Both miR-3197 and miR-2116-5p were identified as promising diagnostic biomarkers for DR. Future research is still needed to explore the molecular mechanisms of miR-3197 and miR-2116-5p in the pathogenesis of DR.
Fulltext Enhancing operational stability of OLEDs based on subatomic modified thermally activated delayed fluorescence compounds

Jung S, Cheung WL, Li SJ, Wang M, Li W, Wang C, et al.

Nat Commun, 2023 Oct 14;14(1):6481.
PMID: 37838720 DOI: 10.1038/s41467-023-42019-6

The realization of operationally stable blue organic light-emitting diodes is a challenging issue across the field. While device optimization has been a focus to effectively prolong device lifetime, strategies based on molecular engineering of chemical structures, particularly at the subatomic level, remains little. Herein, we explore the effect of targeted deuteration on donor and/or acceptor units of thermally activated delayed fluorescence emitters and investigate the structure-property relationship between intrinsic molecular stability, based on isotopic effect, and device operational stability. We show that the deuteration of the acceptor unit is critical to enhance the photostability of thermally activated delayed fluorescence compounds and hence device lifetime in addition to that of the donor units, which is commonly neglected due to the limited availability and synthetic complexity of deuterated acceptors. Based on these isotopic analogues, we observe a gradual increase in the device operational stability and achieve the long-lifetime time to 90% of the initial luminance of 23.4 h at the luminance of 1000 cd m-2 for thermally activated delayed fluorescence-sensitized organic light-emitting diodes. We anticipate our strategic deuteration approach provides insights and demonstrates the importance on structural modification materials at a subatomic level towards prolonging the device operational stability.

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