Communication-Ultrafast Anodized Titania Nanotube Arrays Loaded with Quantum Dots via Ultrasonic Assistance

Self-aligned and firmly-structured titania nanotube arrays (TNAs) with excellent photoelectric response were fabricated by anodization in tens of seconds. Furthermore, TNAs were decorated with CdS quantum dots by ultrasonic-assisted successive ionic layer adsorption and reaction (U-SILAR) method. The resulted CdS/TNAs hybrid shows higher visible light absorption, stronger photo current and stable structure than those of the sample by traditional SILAR method. © 2016 The Electrochemical Society. [DOI: 10.1149/2.0341609jss] All rights reserved. Great efforts have been made to produce titania nanotube arrays (TNAs) by electrochemical anodization method due to its unique advantages. 1-3 Normally, one or more hours are needed to grow TNAs with a length of several micrometers. Quantum dots (QDs) can be easily synthesized and attached on TNAs by successive ionic layer adsorption and reaction (SILAR) method. 9,10 However, the disadvantages of the method are obvious, e.g. the uncontrollable uniformity and dispersion of QDs and the weak adhesion of the QDs on TNAs, etc. In this work, a new approach using ultrasonic-assisted SILAR (U-SILAR) is developed to improve the QDs/TNAs hybrid structures. We found that the QDs could be well distributed throughout the tubes and firmly adhered on TNAs. The transient photoelectric response was investigated. Experimental Titanium foils (0.1 mm in thickness, 99.6% purity) were anodized by an electrochemical setup which consists of Interlock potentiostatgalvanostat (IPD-12003SLU) and a classical two-electrode cell. The electrolyte contains 0.4 M NH 4 F dissolved in a solution of ethylene glycol and DI water (30:1 volume ratio). The anodization was performed at 120 V without stir at 10 • C for 4, 20, 40, 60, and 80s, respectively. The samples were named as TNA120 series. As a reference, another series of samples were prepared at 60 V in the electrolyte which contains 0.27 M NH 4 F dissolved in previous solution at 10 • C for 170, 640 s and 3 h, respectively. These control samples were referred to as TNAs60 series. All samples were post annealed in air at 450 • C for 2 h with a heating speed of 5 • C · min −1 . The annealed TNAs120 (80 s) samples were sequentially dipped in two different solutions for 3 min in each one. One is 0.1 M Cd(NO 3 ) 2 ethanol solution, and the other is 0.1 M Na 2 S methanol solution. The solution containers were put in a 300 W ultrasonic machine during dipping processes. The process was referred to as U-SILAR method. As to the traditional SILAR process, the TNAs120 (80 s) samples were sequentially dipped in the previous solutions without ultrasonic vibration for 5 min. A scanning electron microscope (SEM) Hitachi FE-SEM S4800 was employed for characterizing the morphology of the samples, and the compositional analysis was performed by energy dispersive X-ray spectrometer (EDS) attached to the SEM. The diffuse reflection abz E-mail: [email protected] sorption spectra (DRS) were measured by UV-Vis spectrophotometer (ShimadzuUV-265). The photoelectric response of the samples was recorded with an electrochemical workstation (CHI660E). A white light source was utilized as an excitation source (intensity: 150 mW cm −2 ). Results and Discussion −2 ) and the durations of the first two stages are longer than those of TNAs120. Then the current shows a quasi-steady trend in later time. Different current variations mean different growth processes and morphologies of the resulted samples. As shown by the insets i

Etiological surveillance of viral diarrhea from 2017 to 2019 in Zhangzhou city, Fujian province, China

BackgroundViral diarrhea is one of the major causes of morbidity and mortality in children. This study aimed to conduct etiological surveillance of viral diarrhea in Zhangzhou city, Fujian province, China, from 2017 to 2019 to identify the prevalence, distribution, and characteristics of viral pathogens causing gastrointestinal infections in the region.MethodsStool samples were collected from patients with acute diarrhea in Zhangzhou city, Fujian province, China, from 2017 to 2019. Rotavirus, norovirus, astrovirus, and adenovirus were detected using fluorescence immunochromatography assay.ResultsOf the total 5,627 samples that were collected, at least one of the viruses (rotavirus, norovirus, astrovirus and adenovirus) was found to be positive in 1,422 samples. Rotavirus, norovirus, astrovirus, and adenovirus, were detected in 53.73, 16.68, 15.52, and 14.97%, respectively. Mixed infections were determined in 17.65% of the positive samples. The predominant mixed infections observed were a combination of norovirus and astrovirus, followed by rotavirus and norovirus, and rotavirus and astrovirus. The highest positive rate was observed in the 12–23-month group for rotavirus and adenovirus, while a significantly higher positive rate was observed for norovirus and astrovirus in the 6–11-month group.ConclusionThese findings from this etiological surveillance highlight the significant burden of viral diarrhea in Zhangzhou city, with rotavirus being the predominant pathogen. The identification of common mixed infections provides insights into the complex nature of viral diarrhea transmission. Target interventions and public health strategies should be implemented, particularly during the winter and spring seasons, to prevent and control the spread of viral pathogens causing gastrointestinal infections in this region

Comparative Genomics of Emerging Human Ehrlichiosis Agents

Anaplasma (formerly Ehrlichia) phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia) sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens

Aggregation-Induced Emission (AIE), Life and Health

Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health

Analysis of complete genome sequence of Neorickettsia risticii: causative agent of Potomac horse fever

Neorickettsia risticii is an obligate intracellular bacterium of the trematodes and mammals. Horses develop Potomac horse fever (PHF) when they ingest aquatic insects containing encysted N. risticii-infected trematodes. The complete genome sequence of N. risticii Illinois consists of a single circular chromosome of 879 977 bp and encodes 38 RNA species and 898 proteins. Although N. risticii has limited ability to synthesize amino acids and lacks many metabolic pathways, it is capable of making major vitamins, cofactors and nucleotides. Comparison with its closely related human pathogen N. sennetsu showed that 758 (88.2%) of protein-coding genes are conserved between N. risticii and N. sennetsu. Four-way comparison of genes among N. risticii and other Anaplasmataceae showed that most genes are either shared among Anaplasmataceae (525 orthologs that generally associated with housekeeping functions), or specific to each genome (>200 genes that are mostly hypothetical proteins). Genes potentially involved in the pathogenesis of N. risticii were identified, including those encoding putative outer membrane proteins, two-component systems and a type IV secretion system (T4SS). The bipolar localization of T4SS pilus protein VirB2 on the bacterial surface was demonstrated for the first time in obligate intracellular bacteria. These data provide insights toward genomic potential of N. risticii and intracellular parasitism, and facilitate our understanding of PHF pathogenesis

Role of unfolded protein response in lipogenesis

The signal transduction network in regulating lipid metabolism is a hot topic of biomedical research. Recent research endeavors reveal that intracellular stress signaling from a cellular organelle called endoplasmic reticulum (ER) is critically involved in lipid homeostasis and the development of metabolic disease. The ER is a site where newly-synthesized proteins are folded and assembled into their three-dimensional structures, modified and transported to their precise cellular destinations. A wide range of biochemical, physiological and pathological stimuli can interrupt the protein folding process in the ER and cause accumulation of unfolded or misfolded proteins in the ER lumen, a condition referred to as ER stress. To cope with this stress condition, the ER has evolved highly-specific signaling pathways collectively termed Unfolded Protein Response (UPR) or ER stress response. The UPR regulates transcriptional and translational programs, affecting broad aspects of cellular metabolism and cell fate. Lipogenesis, the metabolic process of de novo lipid biosynthesis, occurs primarily in the liver where metabolic signals regulate expression of key enzymes in glycolytic and lipogenic pathways. Recent studies suggest that the UPR plays crucial roles in modulating lipogenesis under metabolic conditions. Here we address some of recent representative evidence regarding the role of the UPR in lipogenesis

Molecular Characterization of Aegyptianella pullorum (Rickettsiales, Anaplasmataceae)

We sequenced the 16S rRNA and groEL genes of Aegyptianella pullorum, a small bacterium that infects and replicates only in avian red blood cells. A specific PCR test was developed to analyze A. pullorum DNA. Phylogenic analysis revealed A. pullorum is most closely related to Anaplasma spp