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1.
Plant Physiol ; 185(3): 1039-1058, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33793900

RESUMO

Although the nucleolus is involved in ribosome biogenesis, the functions of numerous nucleolus-localized proteins remain unclear. In this study, we genetically isolated Arabidopsis thaliana salt hypersensitive mutant 1 (sahy1), which exhibits slow growth, short roots, pointed leaves, and sterility. SAHY1 encodes an uncharacterized protein that is predominantly expressed in root tips, early developing seeds, and mature pollen grains and is mainly restricted to the nucleolus. Dysfunction of SAHY1 primarily causes the accumulation of 32S, 18S-A3, and 27SB pre-rRNA intermediates. Coimmunoprecipitation experiments further revealed the interaction of SAHY1 with ribosome proteins and ribosome biogenesis factors. Moreover, sahy1 mutants are less sensitive to protein translation inhibitors and show altered expression of structural constituents of ribosomal genes and ribosome subunit profiles, reflecting the involvement of SAHY1 in ribosome composition and ribosome biogenesis. Analyses of ploidy, S-phase cell cycle progression, and auxin transport and signaling indicated the impairment of mitotic activity, translation of auxin transport carrier proteins, and expression of the auxin-responsive marker DR5::GFP in the root tips or embryos of sahy1 plants. Collectively, these data demonstrate that SAHY1, a nucleolar protein involved in ribosome biogenesis, plays critical roles in normal plant growth in association with auxin transport and signaling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Precursores de RNA/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Precursores de RNA/genética , Proteínas Ribossômicas/genética , Ribossomos/genética
2.
Cryobiology ; 99: 131-139, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33248051

RESUMO

The effective long-term cryopreservation of human mesenchymal stem cells is an essential prerequisite step and represents a critical approach for their sustained supply in basic research, regenerative medicine, and tissue engineering applications. Off-the-shelf availability of human umbilical cord-derived mesenchymal stromal cells (UC-MSCs) for regenerative medicine application requires the development of nontoxic, safe, and efficient protocols for cryopreservation. In the long-term low-temperature storage process of cells, traditional manual storage has a great impact on cell activity, recovery, and function due to repeated exposure of cells to room temperature. To minimize the effect of fluctuation in ambient temperature on stored cells, we designed an automatic cryopreservation system that handles cells under controlled temperatures. In this work, UC-MSCs were utilized to investigate and compare the influence of manual and automatic cryopreservation approaches. To simulate the manual process, the UC-MSCs were transferred back and forth repeatedly (up to 400 times) between the liquid nitrogen (LN2) tank (-150 °C) and room temperature by a robotic arm. Similarly, the UC-MSCs from the same batch were collected and transferred repeatedly between two storage units by the automatic cryopreservation system, where the cells were maintained below-150 °C throughout the cold chain process. Viability, percent recovery, adherence capability, cell proliferation, and multilineage differentiation ability were assessed for UC-MSCs. Compared to the manual approach, UC-MSCs handled by the automatic system demonstrated higher viability, percent recovery, and cell proliferation, as well as improved adherence to culture plate with greater potential in multilineage differentiation after 400 temperature cycles. The described entire cold chain system may provide a powerful tool to develop safe, reliable and efficient protocols for manufacturing and banking of UC-MSCs, improving their off-the-shelf availability for regenerative medicine applications.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Criopreservação/métodos , Humanos , Refrigeração , Temperatura , Cordão Umbilical
3.
BMC Public Health ; 18(1): 1363, 2018 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-30537956

RESUMO

BACKGROUND: Globally, diarrhoea is one of the major causes of morbidity and mortality among children under than 5 years of age. There is a scarcity of published data on acute gastroenteritis (AGE) prevalence in Malaysia among children. This study aims to determine factors associated with diarrhoea in children aged less than 5 years in Malaysia. METHOD: Data from the National Health and Morbidity Survey 2016 conducted by Ministry of Health was analysed. This nationwide survey involved 15,188 children below five years old. The survey was carried out using a two-stage stratified sampling design to ensure national representativeness. The Questionnaire from UNICEF's Multiple Indicator Cluster Survey (MCIS) was adapted to suit local requirements. Analysis was done using SPSS Version 23. Descriptive followed by multiple logistic regression were done to identify relevant factors. RESULT: The prevalence of diarrhoea among children under five in Malaysia was 4.4% (95% CI: 3.8,5.2). Analysis using logistic regression indicated that only ethnicity and usage of untreated water were significantly associated with diarrhoea among children after controlling for relevant factors. By ethnicity, children in the 'Other Bumiputera' group had 2.5 times the odds of having diarrhoea compared to children of Malay ethnicity. Children of Indian ethnicity were also at higher risk, at almost double the odds, as well as other ethnic groups (1.5 times). Children who used untreated water supply were two times more likely to develop diarrhoea. CONCLUSION: There is a higher risk of diarrhoea among children of 'Other Bumiputera' ethnicity, Indian ethnicities, and other ethnic groups and those who consume untreated water. Strategies to reduce diarrhoea among children should be targeted towards these at-risk populations. In addition, the Government must strive to ensure universal access to treated clean water in Malaysia and the Ministry of Health must focus on raising awareness on how to prevent diarrhoea.


Assuntos
Diarreia/epidemiologia , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Malásia/epidemiologia , Masculino , Prevalência , Fatores de Risco
4.
J Phys Chem A ; 116(21): 5119-28, 2012 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-22571241

RESUMO

The molecular structures of low-lying isomers of anionic and neutral sodium auride clusters have been studied computationally at the second-order Møller-Plesset perturbation theory level using quadruple-ζ basis sets augmented with a double set of polarization functions. The first vertical detachment energies were calculated at the Møller-Plesset level as the energy difference between the cluster anion and the corresponding neutral cluster. The photodetachment energies of higher-lying ionization channels were calculated by adding electronic excitation energies of the neutral clusters to the first vertical detachment energy. The excitation energies were calculated at the linear response approximate coupled-cluster singles and doubles level using the anionic cluster structures. The obtained ionization energies for NaAu(-), NaAu(2)(-), NaAu(3)(-), NaAu(4)(-), Na(2)Au(2)(-), Na(2)Au(3)(-), Na(3)Au(3)(-), and Na(2)Au(4)(-) were compared to values deduced from experimental photoelectron spectra. Comparison of the calculated photoelectron spectra for a few energetically low-lying isomers shows that the energetically lowest cluster structures obtained in the calculations do not always correspond to the clusters produced experimentally. Spin-component-scaled second-order Møller-Plesset perturbation theory calculations shift the order of the isomers such that the observed clusters more often correspond to the energetically lowest structure, whereas the spin-component-scaled approach does not improve the photodetachment energies of the sodium aurides. The potential energy surface of the sodium aurides is very soft, with several low-lying isomers requiring an accurate electron correlation treatment. The calculations show that merely the energetic criterion is not a reliable means to identify the structures of the observed sodium auride clusters; other experimental information is needed to ensure a correct assignment of the cluster structures. The cluster structures of nonstoichiometric anionic sodium aurides have been determined by comparing calculated ionization energies for low-lying structures of the anionic clusters with experimental data.

5.
Front Neurol ; 13: 926027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147048

RESUMO

Objective: Transcranial ultrasound stimulation (TUS) is a new form of non-invasive brain stimulation. Low-intensity TUS is considered highly safe. We aimed to investigate the effect of low-intensity TUS on hand reaction responses and cortical excitability in healthy adults. Methods: This study used a crossover, randomized, and double-blind design. A total of 20 healthy participants were recruited for the study. All the participants received TUS and sham stimulation on separate days in random order. The finger tapping test (tapping score by using a tablet) and motor evoked potential (MEP) were assessed before and after stimulation, and discomfort levels were assessed using a visual analog scale (VAS) score. Results: No significant differences in tapping score or MEP amplitude between the two experimental conditions were registered before stimulation. After stimulation, tapping scores were increased regardless of the specific treatment, and the real stimulation condition receiving TUS (90.4 ± 11.0 points) outperformed the sham stimulation condition (86.1 ± 8.4 points) (p = 0.002). The MEP latency of real TUS (21.85 ± 1.33 ms) was shorter than that of sham TUS (22.42 ± 1.43 ms) (p < 0.001). MEP amplitude of real TUS (132.18 ± 23.28 µV) was higher than that of sham TUS (114.74 ± 25.5 µV, p = 0.005). There was no significant difference in the discomfort score between the two conditions (p = 0.163). Conclusion: Transcranial ultrasound stimulation (TUS) can decrease the hand reaction response time and latency of the MEP, enhance the excitability of the motor cortex, and improve hand motor function in healthy individuals without obvious discomfort.

6.
Transl Stroke Res ; 13(2): 245-256, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34304360

RESUMO

Identification of patients with high-risk asymptomatic carotid plaques remains a challenging but crucial step in stroke prevention. Inflammation is the key factor that drives plaque instability. Currently, there is no imaging tool in routine clinical practice to assess the inflammatory status within atherosclerotic plaques. We have developed a molecular magnetic resonance imaging (MRI) tool to quantitatively report the inflammatory activity in atherosclerosis using dual-targeted microparticles of iron oxide (DT-MPIO) against P-selectin and VCAM-1 as a smart MRI probe. A periarterial cuff was used to generate plaques with varying degree of phenotypes, inflammation and risk levels at specific locations along the same single carotid artery in an Apolipoprotein-E-deficient mouse model. Using this platform, we demonstrated that in vivo DT-MPIO-enhanced MRI can (i) target high-risk vulnerable plaques, (ii) differentiate the heterogeneity (i.e. high vs intermediate vs low-risk plaques) within the asymptomatic plaque population and (iii) quantitatively report the inflammatory activity of local plaques in carotid artery. This novel molecular MRI tool may allow characterisation of plaque vulnerability and quantitative reporting of inflammatory status in atherosclerosis. This would permit accurate risk stratification by identifying high-risk asymptomatic individual patients for prophylactic carotid intervention, expediting early stroke prevention and paving the way for personalised management of carotid atherosclerotic disease.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Placa Aterosclerótica , Acidente Vascular Cerebral , Animais , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/diagnóstico por imagem , Compostos Férricos , Humanos , Inflamação , Imageamento por Ressonância Magnética/métodos , Camundongos , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Medição de Risco , Acidente Vascular Cerebral/patologia
7.
Dent J (Basel) ; 10(2)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35200256

RESUMO

This study examined the success rates of single immediate implants and their associated biological, hardware and aesthetic complications. Using a developed search strategy, randomized controlled trials (RCTs) on single-unit immediate implants with at least six human participants, a minimum follow-up time of 12 months and published between January 1999 and January 2021 were identified. Data was extracted independently using pre-designed data extraction forms. Information on success rates and associated biological, hardware and aesthetic complications were obtained and assessed. Out of 191 potentially eligible studies, 26 RCTs assessing 1270 patients with a total of 1326 single implants were included and further evaluated. In this review, success rate was reported to be 96.7-100% over a total of 9 studies. However, there was a lack of consensus on a universal success criterion between authors emphasizing the need for agreement. The average follow up was 29 months and most reported complications were aesthetic (63 cases, 4.7%), whilst there were relatively fewer biological, (20 cases, 1.5%), and hardware complications (24 cases, 1.8%). Success rate is an uncommon clinical outcome with 9 out of 26 of the selected RCTs reporting it. In these studies, single immediate implants showed a high success rate with low numbers of biological and hardware complications, and high patient satisfaction with aesthetics were reported in the short-term follow-up of one year.

8.
Nutrients ; 14(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458147

RESUMO

A universal salt iodization (USI) was introduced in Sarawak, Malaysia in 2008 to control the iodine deficiency disorders (IDD) among its population. The purpose of this study is to evaluate the impact of the USI among school children in Sarawak after 10 years of implementation. The data were extracted from 2008 and 2018 Sarawak state-wide IDD surveys. Briefly, both surveys were cross-sectional surveys covering information on the socio-demographic, status of goitre, urinary iodine, and the amount of iodine in the salt samples. A total of 1104 and 988 between the ages of 8 and 10 were involved in the 2008 and 2018 surveys, respectively. The overall prevalence of goitre among the school children in Sarawak was significantly lower in 2018 (0.1%) compared to 2008 (2.9%). The median urinary iodine concentration (UIC) in urine samples had risen significantly from 102.1 µg/L in 2008 to 126.0 µg/L in 2018. In terms of iodine content in salt samples, the median concentration improved significantly in 2018 (35.5 µg/L) compared to 2008 (14.7 µg/L). After 10 years of USI implementation in Sarawak, the results from both surveys confirmed the effectiveness of mandatory USI in increasing the nutritional iodine status of school children in Sarawak.


Assuntos
Bócio , Iodo , Criança , Bócio/epidemiologia , Humanos , Malásia/epidemiologia , Estado Nutricional , Prevalência , Cloreto de Sódio na Dieta
9.
Chemistry ; 17(24): 6781-8, 2011 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-21538614

RESUMO

New heteroleptic ruthenium complexes have been synthesized and used as the sensitizers for dye-sensitized solar cells (DSSCs). The ancillary bipyridine ligand contains rigid aromatic segments (fluorene-, carbazole-, or dithieno[3,2-b:2',3'-d]pyrrole-substituted bipyridine) tethered with a hydrophobic hexyl substituent. The conjugated aromatic segment results in significant bathochromic shift and hyperchromic effects in these complexes compared with Z907 (cis-[RuLL'(NCS)(2)]; L=4,4'-dicarboxylic acid-2,2'-bipyridine, L'=4,4'-dinonyl-2,2'- bipyridine). The long hydrocarbon chains help to suppress the dark current if appropriately disposed. DSSCs that use these complexes exhibit very impressive conversion efficiencies (5.94 to 6.91 %) that surpass that of Z907-based (6.36 %) DSSCs and are comparable with that of N719-based standard cells (7.13 %; N719=cis-di(thiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)ruthenium(II) bis(tetrabutylammonium)) fabricated and measured under similar conditions (active area: 0.5×0.5 cm(2); AM 1.5 sunlight).

10.
Inorg Chem ; 50(10): 4289-94, 2011 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-21491926

RESUMO

A new series of amphiphilic heteroleptic ruthenium(II) sensitizers with a fluorous bis-ponytailed bipyridine ancillary ligand, [Ru(H(2)dcbpy)(4,4'-bis(R(f)CH(2)OCH(2))-2,2'-bpy)(NCS)(2)] [where R(f) = HCF(2)CF(2) (CT4), C(3)F(7) (CT7), and HCF(2)CF(2)CF(2)CF(2) (CT8)], have been synthesized and fully characterized by UV/vis, visible emission, NMR, fast atom bombardment mass spectrometry, and cyclic voltammetric studies. Dye-sensitized solar cells (DSCs) based on these dyes exhibit efficiencies comparable with that of the standard cell based on N719. The conversion efficiency of a CT7- or CT8-based DSC is ~9% higher than that of Z907 with a nonfluorous bis-ponytailed bipyridine ancillary ligand. The fluorous chains were found to increase the dye density on TiO(2) and to help to suppress the dye desorption.

11.
J Health Popul Nutr ; 40(1): 31, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271986

RESUMO

BACKGROUND: Fast-food consumption is an unhealthy dietary behaviour because it increases the risk of diet-related chronic diseases. We aimed to investigate factors associated with fast-food consumption, namely sociodemographic characteristics, body mass index-for-age, meal away from home habit, and intake of various food groups among adolescents in Malaysia. METHODS: We analysed data from the National School-Based Nutrition Survey (NSNS). The NSNS was a nationwide, cross-sectional survey. Multiple-stage stratified cluster random sampling method was applied to obtain a representative sample of adolescents' population. This study recruited adolescents aged 10-18 years who were attending schools. Pre-tested self-administered questionnaires in Malay language were used to obtain relevant information. Frequency of fast-food consumption per week was classified into three groups: "consumed fast-food four to seven days", "consumed fast-food one to three days", and "did not consume fast-food". Intake of food groups was assessed by self-administered food frequency questionnaire. Descriptive and complex sample multinomial logistic regression analyses were performed in data analysis. RESULTS: A total of 26,383 from 40,012 selected adolescents completed all the relevant questions for this study. Of those surveyed, 13.5% of the respondents consumed fast-food 4 to 7 days, 69.3% of the respondents consumed fast food 1 to 3 days, and 17.2% of them did not consume fast-food in a typical week. Frequency of fast-food consumptions (4 to 7 days and 1 to 3 days per week) was significantly associated with age; sex; ethnicity; locality of schools; frequency of eating out; and not consuming recommended intake of cereals or grains, vegetables, and meat or poultry or eggs. CONCLUSION: In conclusion, age; sex; ethnicity; locality of schools; frequency of eating out per week; imbalanced intake of cereals or grains, meat, or poultry or eggs; and inadequate vegetable intake were significantly associated with fast-food consumption among adolescents in Malaysia. The findings of this study will be useful for policy makers in promoting healthy food choices among adolescents in Malaysia.


Assuntos
Fast Foods , Comportamento Alimentar , Adolescente , Estudos Transversais , Humanos , Malásia , Inquéritos Nutricionais , Instituições Acadêmicas
12.
Food Nutr Bull ; 42(3): 406-413, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34024187

RESUMO

BACKGROUND: A mandatory universal salt iodization (USI) has been implemented in Sarawak, Malaysia since 2008. OBJECTIVES: The aim of this study is to assess the current iodine status among school-aged children (SAC) and pregnant women (PW) after 10 years of USI implementation in Sarawak. METHODS: This cross-sectional survey among school-aged children and pregnant women was conducted between July and October 2018 in Sarawak. The multistage proportionate to population size sampling technique was used to select 30 schools and 30 maternal and child health care clinics. A total of 1200 children aged 8 to 10 years and 750 first-trimester pregnant women were randomly selected to participate in the study. Iodine excretion level in urine was determined according to the World Health Organization classification. RESULTS: A total of 988 children and 677 PW participated in the study with a response rate of 82.3% and 90.2%, respectively. The overall median urinary iodine concentration (UIC) level among the children was 126.0 µg/L (interquartile range [IQR], 71.0-200.9 µg/L) and classified as adequate iodine status. The median UIC among PW was 123.9 µg/L (IQR, 56.5-192.1µg/L) indicating inadequate iodine status. CONCLUSION: The present findings indicate that despite adequate iodine status in children, the majority of PW still showed inadequate iodine status. Thus, comprehensive monitoring of the iodine deficiency disorder problem among PW is warranted.


Assuntos
Iodo , Criança , Estudos Transversais , Feminino , Humanos , Malásia/epidemiologia , Estado Nutricional , Gravidez , Gestantes , Instituições Acadêmicas , Cloreto de Sódio na Dieta
13.
Eur J Radiol ; 142: 109840, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34237492

RESUMO

PURPOSE: To evaluate the value of preoperative computed tomography (CT) features including morphologic and quantitative features for predicting the Ki-67 labeling index (Ki-67LI) of gastric gastrointestinal stromal tumors (GISTs). METHODS: We retrospectively included 167 patients with gastric GISTs who underwent preoperative contrast-enhanced CT. We assessed the morphologic features of preoperative CT images and the quantitative features including the maximum diameter of tumor, total tumor volume, mean total tumor CT value, necrosis volume, necrosis volume ratio, enhanced tissue volume, and mean CT value of enhanced tissue. Potential predictive parameters to distinguish the high-level Ki-67LI group (>4%, n = 125) from the low-level Ki-67LI group (≤4%, n = 42) were compared and subsequently determined in multivariable logistic regression analysis. RESULTS: Growth pattern (p = 0.036), shape (p = 0.000), maximum diameter (p = 0.018), total tumor volume (p = 0.021), mean total tumor CT value (p = 0.009), necrosis volume (p = 0.006), necrosis volume ratio (p = 0.000), enhanced tissue volume (p = 0.027), and mean CT value of enhanced tissue (p = 0.004) were significantly different between the two groups. Multivariate logistic regression analysis indicated that lobulated/irregular shape (odds ratio [OR] = 3.817; p = 0.000) and high necrosis volume ratio (OR = 1.935; p = 0.024) were independent factors of high-level Ki-67LI. CONCLUSIONS: Higher necrosis volume ratio in combination with lobulated/irregular shape could potentially predict high expression of Ki-67LI for gastric GISTs.


Assuntos
Tumores do Estroma Gastrointestinal , Neoplasias Gástricas , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Antígeno Ki-67 , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X
14.
Chemistry ; 16(10): 3184-93, 2010 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-20119994

RESUMO

A novel series of dipolar organic dyes containing diarylamine as the electron donor, 2-cyanoacrylic acid as the electron acceptor, and fluorene and a heteroaromatic ring as the conjugating bridge have been developed and characterized. These metal-free dyes exhibited very high molar extinction coefficients in the electronic absorption spectra and have been successfully fabricated as efficient nanocrystalline TiO(2) dye-sensitized solar cells (DSSCs). The solar-energy-to-electricity conversion efficiencies of DSSCs ranged from 4.92 to 6.88%, which reached 68-96% of a standard device of N719 fabricated and measured under the same conditions. With a TiO(2) film thickness of 6 microm, DSSCs based on these dyes had photocurrents surpassing that of the N719-based device. DFT computation results on these dyes also provide detailed structural information in connection with their high cell performance.

15.
Chemistry ; 16(43): 12873-82, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20886474

RESUMO

A detailed study of the synthesis and photophysical properties of a new series of dipolar organic photosensitizers that feature a 1,3-cyclohexadiene moiety integrated into the π-conjugated structural backbone has been carried out. Dye-sensitized solar cells (DSSCs) based on these structurally simple dyes have shown appreciable photo-to-electrical energy conversion efficiency, with the highest one up to 4.03 %. Solvent-dependent fluorescence studies along with the observation of dual emission on dye 4 b and single emission on dyes 4 a and 32 suggest that dye 4 b possesses a highly polar emissive excited state located at a lower-energy position than at the normal emissive excited state. A detailed photophysical investigation in conjunction with computational studies confirmed the twisted intramolecular charge-transfer (TICT) state to be the lowest emissive excited state for dye 4 b in polar solvents. The relaxation from higher-charge-injection excited states to the lowest TICT state renders the back-electron transfer process a forbidden one and significantly retards the charge recombination to boost the photocurrent. The electrochemical impedance under illumination and transient photovoltage decay studies showed smaller charge resistance and longer electron lifetime in 4 b-based DSSC compared to the DSSCs with reference dyes 4 a and 32, which further illustrates the positive influence of the TICT state on the performance of DSSCs.

16.
J Org Chem ; 75(22): 7877-86, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-20973531

RESUMO

The synthesis, electronic properties, and performance in dye-sensitized solar cells (DSSCs) of four cone-shaped organic dyes (ITD, ITD-Th, ITD-Hx, and ITD-OM) containing the isotruxene π-scaffold are reported. Selective substitution of the unsymmetrical isotruxene core with two diarylamino donors and one cyanocarboxylic acid acceptor was achieved by using a prefunctionalized dibromoisotruxene building block. The ortho-para-branched isotruxene core allows strong electronic couplings among the donors and the acceptor, leading to red-shifted absorption profiles with significant charge-transfer character. All four isotruxene dyes display reversible anodic waves in cyclic voltammagrams with both HOMO and LUMO potentials suitable for application in DSSCs. The DSSCs fabricated with these cone-shaped organic dyes exhibited high open-circuit voltages (0.67-0.76 V) and fill factors (0.67-0.72) with a power conversion efficiency (η) up to 5.45%, which is 80% of the ruthenium dye N719-based standard cell fabricated and measured under the same conditions.

17.
Sci Adv ; 6(10): eaay0317, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32181342

RESUMO

European eel (Anguilla anguilla) is a critically endangered species requiring CITES permits for international trade. Despite the fact that no imports to Hong Kong were declared within the last 2 years, our study found that this species is still commonly sold in major supermarket chains across Hong Kong. In a COI barcoding survey of 49 retail vendors encompassing 13 brands, 9 of 13 carried A. anguilla, and 45% of all eel products available at retail outlets (n = 49) were unambiguously identified as A. anguilla. Considering the visual similarity of eel species and disproportionate amount of undeclared A. anguilla available for consumption, this finding raises urgent concerns regarding the enforcement of international CITES trade regulations. Furthermore, the prevalence of A. anguilla in supermarkets highlights how illicit wildlife products are not solely limited to specialized affluent buyers; some species have entered mainstream distribution networks for the average consumer.


Assuntos
Anguilla/genética , Comércio/ética , DNA/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Espécies em Perigo de Extinção , Proteínas de Peixes/genética , Anguilla/classificação , Animais , Conservação dos Recursos Naturais/legislação & jurisprudência , Código de Barras de DNA Taxonômico , Hong Kong , Filogenia , Alimentos Marinhos/economia
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 6095-6098, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019361

RESUMO

Gene mutation prediction in hepatocellular carcinoma (HCC) is of great diagnostic and prognostic value for personalized treatments and precision medicine. In this paper, we tackle this problem with multi-instance multi-label learning to address the difficulties on label correlations, label representations, etc. Furthermore, an effective oversampling strategy is applied for data imbalance. Experimental results have shown the superiority of the proposed approach.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Humanos , Neoplasias Hepáticas/genética , Aprendizado de Máquina , Mutação
19.
Artigo em Inglês | MEDLINE | ID: mdl-33383635

RESUMO

Internet addiction (IA) among adolescents is an issue of growing concern with adverse effects on adolescents' health and social functioning. This study aims to determine the prevalence of IA among school-going adolescents in Malaysia and its associated factors-specifically, lifestyle factors. A nationwide cross-sectional school-based health survey was conducted in 2017 among 27,497 students from 212 randomly selected secondary schools. Information regarding sociodemography, lifestyle, and internet use was obtained using a self-administered questionnaire. IA was measured using the Malay Version of Internet Addiction Test (MVIAT). The prevalence of internet addiction was 29.0%. A multivariable logistic analysis revealed that inadequate fruit and vegetable intakes, consumed carbonated soft drinks at least once a day, consumed fast food at least three days/week, sedentary behavior, current E-cigarette users, and ever/current alcohol drinkers were lifestyle factors significantly associated with IA. Adolescents from urban schools, of higher school grade, and those whose parents are married but living apart were also found to have a greater risk for internet addiction. A positive association was found between IA with unhealthy dietary and lifestyle behaviors among adolescents. The modification of lifestyle factors needs to be considered while developing strategies and interventions for awareness-raising and prevention of IA among adolescents.


Assuntos
Transtorno de Adição à Internet/epidemiologia , Estilo de Vida , Adolescente , Estudos Transversais , Sistemas Eletrônicos de Liberação de Nicotina , Feminino , Humanos , Malásia/epidemiologia , Masculino , Fatores de Risco , Instituições Acadêmicas , Inquéritos e Questionários
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5814-5817, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019296

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and the fourth most common cause of cancer-related death worldwide. Understanding the underlying gene mutations in HCC provides great prognostic value for treatment planning and targeted therapy. Radiogenomics has revealed an association between non-invasive imaging features and molecular genomics. However, imaging feature identification is laborious and error-prone. In this paper, we propose an end-to-end deep learning framework for mutation prediction in APOB, COL11A1 and ATRX genes using multiphasic CT scans. Considering intra-tumour heterogeneity (ITH) in HCC, multi-region sampling technology is implemented to generate the dataset for experiments. Experimental results demonstrate the effectiveness of the proposed model.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Mutação , Prognóstico , Tomografia Computadorizada por Raios X
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