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This study investigates the relationship between the development of the life insurance market and bank stability within the context of developing countries. We used data from 2012 to 2020 across 108 developing countries and applied econometric techniques, including fixed-effect and system generalized method of moments (GMM) methods, to test the relationship between the life insurance market size, life insurance market growth, and bank stability at the country level. Our results indicate a positive relationship between life insurance market size and bank stability, i.e., a large life insurance market can help increase bank stability in developing countries. However, these countries should refrain from developing their life insurance markets too quickly; according to our empirical results, there is an inverted U-shaped relationship between life insurance market growth and bank stability. In the context of the growing life insurance market in developing countries as well as the increasing cooperation between banks and insurance companies towards expanding the life insurance market in these countries, our research provides important policy implications for ensuring the stability for financial markets in general., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author. Published by Elsevier Ltd.)

Despite being an excellent surface enhanced Raman scattering (SERS) active material, gold nanoparticles were difficult to be loaded onto the surface of filter paper to fabricate flexible SERS substrates. In this study, electrochemically synthesized gold nanoparticles (e-AuNPs) were deposited on graphene oxide (GO) nanosheets in solution by ultrasonication, resulting in the formation of a GO/Au hybrid material. Thanks to the support of GO, the hybrid material could adhere onto the surface of filter paper, which was immersed into a GO/Au solution for 24 h and dried naturally at room temperature. The paper-based materials were then employed as substrates for a surface enhanced Raman scattering (SERS) sensing platform to detect tricyclazole (TCZ), a widely used pesticide, resulting in better sensitivity compared to the use of paper/Au SERS sensors. With the most optimal GO content of 4%, paper/GO/Au SERS sensors could achieve a limit of detection of 1.32 × 10 -10 M in standard solutions. Furthermore, the filter paper-based SERS sensors also exhibited significant advantages in sample collection in real samples. On one hand, the sensors were dipped into orange juice, allowing TCZ molecules in this real sample to be adsorbed onto their SERS active surface. On the other hand, they were pasted onto cucumber skin to collect the analytes. As a result, the paper/GO/Au SERS sensors could sense TCZ in orange juice and on cucumber skin at concentrations as low as 10 -9 M (∼2 ppb). In addition, a machine learning model was designed and developed, allowing the sensing system to discriminate TCZ from nine other organic compounds and predict the presence of TCZ on cucumber skin at concentrations down to 10 -9 M., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Our study delved into the detailed investigation of Cs 2 SnBr 6 double perovskites, focusing on their electrical properties, lattice dynamics, and stability. The direct bandgap for Cs 2 SnBr 6 was estimated to be at 2.93 eV. One external translational mode of the Cs + lattice with T 2g symmetry and three internal modes of the octahedral with A 1g , E g , and T 2g symmetries are defined by calculated lattice dynamics, experimental micro-Raman scattering. We show a correlation with first-principles calculations, validating using a band-structured electronic approach to understanding the behavior of charge carriers, and electron-phonon interactions in Cs 2 SnBr 6 . We propose that electron-vibration interactions result in self-trapped excitons (STEs) displaying significant Stokes shifts (0.508 eV) and broad-spectrum emission. Understanding the behavior of STEs is fundamental for their optoelectronic applications., (© 2024 IOP Publishing Ltd.)

Amikacin is an aminoglycoside antibiotic widely used to treat various bacterial infections in humans. However, elevated concentrations of amikacin can damage the cochlear nerve. Thus, accurate and rapid amikacin detection is crucial. In this study, we developed an "on-off" fluorescence nanosensor for highly sensitive amikacin determination based on a composite of carbon quantum dots (CQDs) and gold nanoparticles (AuNPs). The method quenches CQD fluorescence (turn-off) when they bind to AuNPs but restores it (turn-on) when amikacin binds and releases the CQDs. Adding Cu 2+ enhances sensitivity by cross-linking amikacin-coated AuNPs. Under optimal conditions (pH 4, 1 mM Na 2 SO 4 , 1 mM CuSO 4 ), the method achieved a low detection limit of 3.5 × 10 -11 M (0.02 ppb), a wide linear range (10 -10 to 10 -8 M), high precision (RSD < 5 %), and a rapid 2-minute response time. Exceptional selectivity was observed over other antibiotics. The CQDs/AuNPs-based sensor successfully detected amikacin in pharmaceutical and surface water samples. This approach offers a fast on-site analytical method for amikacin detection, with potential applications in clinical and environmental settings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Rice holds a significant position in the global food supply chain, particularly in Asian, African, and Latin American countries. However, rice pests and diseases cause significant damage to the supply and growth of the rice cultivation industry. Therefore, this article provides a high-quality dataset that has been reviewed by agricultural experts. The dataset is well-suited to support the development of automation systems and smart farming practices. It plays a vital role in facilitating the automatic construction, detection, and classification of rice diseases. However, challenges arise due to the diversity of the dataset collected from various sources, varying in terms of disease types and sizes. This necessitates support for upgrading and enhancing the dataset through various operations in data processing, preprocessing, and statistical analysis. The dataset is provided completely free of charge and has been rigorously evaluated by agricultural experts, making it a reliable resource for system development, research, and communication needs., (© 2024 The Author(s).)

Stock price crash risk is of particular interest in developing countries as it poses a significant threat to investors and can have detrimental effects on the stability of emerging markets. This study investigates the role of financial flexibility in preventing stock price crash risk in the Vietnamese stock market, with a specific focus on the COVID-19 pandemic. Using the fixed-effect, system GMM, and quantile regression methods on a sample of 645 Vietnamese listed firms from 2011 to 2021, this study found that financial flexibility has a significant impact on preventing stock price crash risk. This effect was augmented during the COVID-19 crisis. Furthermore, this study found that financial flexibility mitigated the impact of the COVID-19 crisis on stock price crash risk. The findings provide important implications for firm regulators, shareholders, and investors to respond to similar future crises., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

Magnetite nanoparticles (Fe 3 O 4 NPs) are among the most effective Fenton-Like heterogeneous catalysts for degrading environmental contaminants. However, Fe 3 O 4 NPs aggregate easily and have poor dispersion stability because of their magnetic properties, which seriously decrease their catalytic efficiency. In this study, a novel environmentally friendly method for synthesising Fe 3 O 4 @CA was proposed. Fe 3 O 4 NPs were immobilized on the 3D cellulose aerogels (CAs) in order to augment the degradation efficiency of p -nitrophenol (PNP) treatment and make the separation of the catalyst accessible by vacuum filtration method. Besides, CAs were fabricated from a cellulose source extracted from water hyacinth by using different cross-linking agents, such as kymene (KM) and polyvinyl alcohol-glutaraldehyde system (PVA-GA), and other drying methods, including vacuum thermal drying and freeze drying, were evaluated in the synthesis process. As-synthesized samples were analysed by various methods, including Powder X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray analysis and Brunauer-Emmett-Teller. Then, using ultraviolet-visible spectroscopy, the difference in the degradability of PNP of the obtained material samples was also investigated to determine their potential applications. Results highlighted that the Fe 3 O 4 -3@CA-KF catalyst with an Fe 3 O 4 loading of 0.40 g/g CA used KM as a cross-linker and the freeze-drying method demonstrated the highest PNP removal efficiency (92.5 %) in all Fe 3 O 4 @CA samples with a H 2 O 2 content of 5 g/L. The degradation kinetics and well-fitted pseudo-first-order model were investigated. Notably, after five successive PNP degradation experiments, this catalyst retained ∼80 % of the ability to degrade PNP, indicating its outstanding reusability. In environmental remediation, this study provides valuable insights into the development of simply separated and high-efficiency catalysts for heterogeneous catalytic reactions., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

A phenomenon known as "blue-light leakage" caused by overheating pcW-LEDs has recently been identified, and it poses a risk to users. This study focuses on investigating and optimizing a solution to address this issue. To tackle the problem of overheating and blue light leakage, we explored the application of a specific thermochromic material called crystal nano cellulose (CNC). We introduced CNC inside the epoxy lens of white LEDs. Importantly, under standard conditions, CNC has a negligible impact on the optical properties of the output white light. However, when overheating conditions arise, leading to blue light leakage, the temperature increase triggers a darkening effect in CNC. This thermochromic behavior of CNC allows it to strongly absorb the blue light, resulting in a significant suppression of the output luminous flux. As a result, the lamp dims, which not only prevents the user's eyes from being exposed to harmful bluish light but also serves as an indicator of aging in the pcW-LED. By implementing CNC as a responsive material in the design of white LEDs, this study offers a practical and effective solution to mitigate the negative effects of blue-light leakage caused by overheating. This improvement enhances the safety and comfort of users while also providing an early warning system for the aging of pcW-LEDs., (© 2023. Springer Nature Limited.)

Objectives: The mitochondrial ribosomal protein L14 (MRPL14) is encoded by a nuclear gene and participates in mitochondrial protein translation. In this study, we aimed to investigate the role of MRPL14 in thyroid cancer., Methods: We investigated the association between MRPL14 expression and clinicopathological features using The Cancer Genome Atlas (TCGA) and Chungnam National University Hospital (CNUH) databases. Functional studies of MRPL14, including proliferation, migration, invasion, mitochondrial oxidative phosphorylation and reactive oxygen species (ROS) production, were performed in papillary thyroid cancer (PTC) cell lines (B-CPAP and KTC-1)., Results: Based on the TCGA dataset, PTC tissues lost mitochondrial integrity and showed dysregulated expression of overall mitoribosomal proteins (MRPs) compared with normal thyroid tissues. Of 78 MRPs, MRPL14 was highly expressed in thyroid cancer tissues. MRPL14 overexpression was significantly associated with advanced tumor stage, extrathyroidal extension, and lymph node metastasis. MRPL14 increased cell proliferation of thyroid cancer and promoted cell migration via epithelial-mesenchymal transition-related proteins. Moreover, MRPL14 knockdown reduced the expression of oxidative phosphorylation complex IV (MTCO1) and increased the accumulation of ROS. Cotreatment with a ROS scavenger restored cell proliferation and migration, which had been reduced by MRPL14 knockdown, implying that ROS functions as a key regulator of the oncogenic effects of MRPL14 in thyroid cancer cells., Conclusion: Our findings indicate that MRPL14 may promote cell growth, migration, and invasion by modulating ROS in thyroid cancer cells.

In this paper, we propose an algorithm for estimating the beam aperture of the acoustic transducers by using the geometric backscattering model for side-scan sonar systems. The geometric backscattering model is developed to describe the propagation paths of the signal transmitted from the transducers towards the seabed and backscatters to the hydrophones. To evaluate our proposed algorithm, we have developed a side-scan sonar system. The side-scan sonar system uses two transducers, operating on two different frequencies and focusing on two different wave beams, to scan the images of the seabed. The proposed algorithm provides the estimated beam apertures of each transducer. Our obtained results agree quite well with the parameters provided by the manufacturers. Moreover, these results are used to calibrate the scanned images. We provide the scanned sonar 3D images of the Dong Do lakebed, Vietnam, to justify our proposal.

This study investigated the impact of the COVID-19 crisis on firm risk and performance in different country-level governance qualities in the MENA region. Analyzing a sample of 739 non-financial listed firms in 12 MENA countries for the period 2011-2020, we found that the COVID-19 crisis negatively impacted the performance of firms, especially low-performance firms, in most industries, and increased firm risk in general. Moreover, we found that national governance quality plays an important role in mitigating the negative impact of the COVID-19 crisis on firm operations. Specifically, national governance quality reduces the negative impact of the COVID-19 crisis on firm performance and the positive impact of the crisis on firm risk. The results are consistent with our contention that national governance quality contributes to creating a positive environment for businesses activities and reducing economic shocks., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Almustafa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Oral squamous cell carcinoma (OSCC) has high recurrence and mortality rates despite advances in diagnosis and treatment. Therefore, it is necessary to identify new biomarkers for early detection, efficient monitoring, and prognosis prediction. Since microRNA (miRNA) is stable and detectable in serum, it has been reported to inform the diagnosis and monitor disease progression through liquid biopsy. In this study, a circulating specific miRNA panel in OSCC patients was developed, and its usefulness as a dynamic monitor was validated. Small RNAs were extracted from the serum of OSCC patients (n = 4) and normal controls (n = 6) and profiled using next-generation sequencing. NGS identified 42 differentially expressed miRNAs (DEmiRNAs) in serum between patients with OSCC and healthy controls, with threefold differences (p < 0.05). Combining the 42 DEmiRNAs and The Cancer Genome Atlas (TCGA) databases OSCC cohort, 9 overlapping DEmiRNAs were screened out. Finally, 4 significantly up-regulated miRNAs (miR-92a-3p, miR-92b-3p, miR-320c and miR-629-5p) were identified from OSCC patients via validation in the Chungnam National University Hospital cohort. Application of the specific miRNA panel for distinguishing OSCC patients from healthy controls produced specificity and sensitivity of 97.8 and 74%, respectively. In addition, the serum levels of these 4 miRNAs significantly decreased after complete surgical resection and increased after recurrence. We suggest that circulating 4-miRNA panel might be promising non-invasive predictors for diagnosing and monitoring the progression of patients with OSCC., (© 2023. The Author(s).)

Ultraviolet C (UVC) radiation has been considered a possible option to alleviate the seriousness of black spots on bananas during preservation which help increase economic efficiency. In this study, using 275 nm UVC light-emitting diodes (LEDs), a preliminary cavity with dimensions of 30 × 30 × 30 cm was designed and fabricated to aid in reducing black spots on bananas with the aim of application in the factory conveyor belts. The UVC irradiance distribution was thoroughly monitored for many sections at different box heights in both simulation and measurement, with a dominant range of 6-9 W/m 2 in the middle. Afterward, trials were conducted in vitro and in vivo at different selected UVC doses. The results in vitro revealed that a dose of over 0.36 kJ/m 2 has an excellent effect on inhibiting the colonial germination of fungal Colletotrichum musae, a common species of fungi causing black spot disease on bananas. In vivo conditions, with a short exposure time of around 5 s, the black spots on UVC-irradiated banana peel significantly reduced with minimal sensory damage compared to a control banana via observation after seven days from treatment. Finally, the optimal UVC dose is proposed from 0.030 to 0.045 kJ/m 2 for the one-time treatment when considering the upper surface of the banana. With flexibility advantage and short exposure time, the fabricated cavity (box) promises to bring a lot of application potential to aid banana preservation in factories and households., (© 2022. The Author(s).)

This study analyzes the effectiveness of bank risk management in ASEAN countries and examines the specific role of risk governance in enhancing a bank's risk management effectiveness. Our results show that the risk management effectiveness of banks in ASEAN countries is low. Furthermore, by focusing on the insolvency risk, credit risk, and operational risk management of banks in ASEAN countries, the dynamic panel models using the two-step GMM method provide evidence that risk governance structure and its effectiveness positively correlate with risk management effectiveness in banks. Based on our findings, the regulators can establish the guidelines related to risk governance to manage a bank's risk management activities and maintain bank stability., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors.)

In this study, we proposed and demonstrated a circuit design for solving problems related to blue light leakage (e.g., eye damage) when phosphor-converted white light-emitting diodes (pcW-LEDs) overheat. This circuit only needs a positive thermal coefficient thermistor, resistor, and diodes in series and parallel; thus, it can easily be integrated into components. Simulations and corresponding experimental results show that this method can accurately suppress the overheating component's injection current and allow for LEDs to work normally after returning to the operating temperature. It thus allows the user's eyes to be actively protected, e.g., to avoid exposure to the bluish light when overheating occurs. In addition, the quenching of luminous flux is a signal to remind the user to replace the LED. The proposed method is low-cost, effective, simple, and useful for increasing the quality of LED lighting and biological safety., (© 2022. The Author(s).)

In this paper, we propose and demonstrate to use of a single reflector with 68 segments to project vehicle low beam and high beam with the use of a GaN-based mini-LED matrix, which is a 5 × 6 LED die array. The design of the reflector is based on light field technology in considering etendue from the light source across the segments. The group of the segments with smaller etendue from the LED dies in the bottom 2 rows are used to project low beams. When the other LED dies are turned on, the reflector will project light upward and form the high beam. The selection of the turn-on LED dies in the mini-LED matrix can adjust the width of the illumination pattern so that an adaptive low/high beam can be performed. Besides, to extend the functionality of the headlamp module, we propose to dispense IR phosphor on LED dies in the high-beam zone of the GaN-based mini-LED matrix. Thus the vehicle can emit IR high beam, which can be imaged through a camera and can be incorporated with machine vision for an autonomous vehicle without using a complicated adaptive headlight to avoid glare. The proposed multi-function in spatial and spectral domains will be helpful to various applications with use of a mini-LED matrix., (© 2022. The Author(s).)

In the academic environment, checking attendance can help lecturers better evaluate students' performance in university. Traditional attendance checking has some disadvantages, which are wasting time and effort. The automatic attendance monitoring system, on the other hand, not only can help us solve these drawbacks but also bring a high-accuracy result compared to manually checking. The method uses ultra-high-frequency (UHF) RFID technology with four circularly polarized antennas, combined with the high-definition camera system used for face recognition that allows the system to recognize students' faces. The system will check the attendance of students in offline classes through an RFID reader and camera which are set up in classrooms. In the case of online study in which students learn from home, the system can use students' cameras directly from their laptops and smartphones to recognize their faces and check attendance. The web-based information system has real-time updates with attendance monitoring that allows the lecturer to review or determine the student's attendance status. In the event of unexpected issues on the student side, the system enables lecturers to check attendance manually after receiving the student's request. Our system, furthermore, can automatically generate a weekly report about student's learning status in each class and provide the overall proportion of students' commitment to attending classes for the lecturer. This paper brings some initial simulations of the system to give a more detailed picture of how the new system works and interacts. Besides, this manuscript provides a detailed performance analysis about the system with RFID and camera, then has an evaluation based on class' learning outcome. The time, precision, and accuracy of our system are considered., Competing Interests: Conflict of interestThe authors declare that we have no conflict of interest., (© The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd 2022, Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Ag x -Zn 100-x -BTC/GO composites (BTC: benzene-1,3,5-tricarboxylic, GO: graphene oxide) with different Ag/Zn molar ratios were synthesized using microwave-assisted hydrothermal treatment. The Ag x -Zn 100-x -BTC/GO exhibited excellent photocatalytic performance in the reactive yellow 145 dye (RY-145) degradation under irradiation of visible light with nearly 100% of RY-145 removal after 35 min, as compared to Zn-BTC/GO and Ag-BTC/GO. Reactive oxygen species scavenging assays have shown that the holes (h + ) and superoxide radical anion (O 2 -• ) play a primary role in RY-145 degradation. Based on the band structure of materials, the Z-scheme photocatalytic mechanism was suggested. The effect of catalyst dosage, pH and dye concentration on the efficiency of photocatalytic activity of bimetallic Ag 50 -Zn 50 -BTC/GO was also investigated. The improvement in photocatalytic activity of bimetallic Ag 50 -Zn 50 -BTC/GO could be given by the synergism of (i) absorption of visible light confirmed by UV-Vis diffuse reflectance spectra; (ii) the increased lifetime as evidenced by photoluminescence spectra and transient photocurrent response; (iii) the increased oxygen vacancy defects as confirmed by X-ray photoelectron spectroscopy results. The degradation pathway of RY-145 dye was also predicted based on liquid chromatography-mass spectrometer analysis. The removed chemical oxygen demand, biological oxygen demand, total organic carbon outcomes indicated the high mineralization ability for RY-145 degradation over Ag 50 -Zn 50 -BTC/GO., (Copyright © 2021 Elsevier B.V. All rights reserved.)

By utilizing the Fixed effect and GMM estimators for a sample of 57 Islamic banks and 102 conventional banks from 10 countries for the period 2002-2018, we examine the effect of the audit committees' and Sharia committees' effectiveness on the bank risk-taking behavior and its transmission mechanisms. The results reveal that an audit committee's independence, number of meetings, and financial expertise negatively affect conventional banks' risk-taking, suggesting that the high effectiveness of their audit committees may constrain banks' risk-taking activities. However, no such relationship is evident or observed case of Islamic banks. Instead, with a different transmission mechanism, the proportion of female members and the financial expertise in the Sharia committees negatively affect risk-taking, but the Sharia committee size positively affects risk-taking in Sharia banks. These results indicate that a Sharia committee's high effectiveness can constrain risk-taking behaviors in Islamic banks., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Multilateration tracking systems (MLTSs) are used in industrial three-dimensional (3D) coordinate measuring applications. For high-precision measurement, system parameters must be calibrated properly in advance. For an MLTS using absolute distance measurement (ADM), the conventional self-calibration method significantly reduces estimation efficiency because all system parameters are estimated simultaneously using a complicated residual function. This paper presents a novel self-calibration method that optimizes ADM to reduce the number of system parameters via highly precise and separate estimations of dead paths. Therefore, the residual function to estimate the tracking station locations can be simplified. By applying a suitable mathematical procedure and solving the initial guess problem without the aid of an external device, estimation accuracy of the system parameters is significantly improved. In three self-calibration experiments, with ADM repeatability of approximately 3.4 µm, the maximum deviation of the system parameters estimated by the proposed self-calibration method was 68.6 µm, while the maximum deviation estimated by the conventional self-calibration method was 711.9 µm. Validation of 3D coordinate measurements in a 1000 mm × 1000 mm × 1000 mm volume showed good agreement between the proposed ADM-based MLTS and a commercial laser tracker, where the maximum difference based on the standard deviation was 17.7 µm. Conversely, the maximum difference was 98.8 µm using the conventional self-calibration method. These results confirmed the efficiency and feasibility of the proposed self-calibration method.

Flash floods are widely recognized as one of the most devastating natural hazards in the world, therefore prediction of flash flood-prone areas is crucial for public safety and emergency management. This research proposes a new methodology for spatial prediction of flash floods based on Sentinel-1 SAR imagery and a new hybrid machine learning technique. The SAR imagery is used to detect flash flood inundation areas, whereas the new machine learning technique, which is a hybrid of the firefly algorithm (FA), Levenberg⁻Marquardt (LM) backpropagation, and an artificial neural network (named as FA-LM-ANN), was used to construct the prediction model. The Bac Ha Bao Yen (BHBY) area in the northwestern region of Vietnam was used as a case study. Accordingly, a Geographical Information System (GIS) database was constructed using 12 input variables (elevation, slope, aspect, curvature, topographic wetness index, stream power index, toposhade, stream density, rainfall, normalized difference vegetation index, soil type, and lithology) and subsequently the output of flood inundation areas was mapped. Using the database and FA-LM-ANN, the flash flood model was trained and verified. The model performance was validated via various performance metrics including the classification accuracy rate, the area under the curve, precision, and recall. Then, the flash flood model that produced the highest performance was compared with benchmarks, indicating that the combination of FA and LM backpropagation is proven to be very effective and the proposed FA-LM-ANN is a new and useful tool for predicting flash flood susceptibility.

The coding sequence of a peroxidase from the secretome of Pleurotus sapidus was cloned from a cDNA library. Bioinformatic analyses revealed an open reading frame of 1551 bp corresponding to a primary translation product of 516 amino acids. The DyP-type peroxidase was heterologously produced in Trichoderma reesei with an activity of 55,000 U L -1 . The enzyme was purified from the culture supernatant, biochemically characterized and the kinetic parameters were determined. The enzyme has an N-terminal signal peptide composed of 62 amino acids. Analysis by Blue Native PAGE and activity staining with ABTS, as well as gel filtration chromatography showed the native dimeric state of the enzyme (115 kDa). Analysis of the substrate range revealed that the recombinant enzyme catalyzes, in addition to the conversion of some classic peroxidase substrates such as 2,2'-azino-bis(3-ethylthiazoline-6-sulfonate) and substituted phenols like 2,6-dimethoxyphenol, also the decolorization of the anthraquinonic dye Reactive Blue 5. The enzyme also catalyzes bleaching of natural colorants such as β-carotene and annatto. Surprisingly, β-carotene was transformed in the presence and absence of H 2 O 2 by rPsaDyP, however enzyme activity was increased by the addition of H 2 O 2 . This indicates that the rPsaDyP has an oxidase function in addition to a peroxidase activity. As a consequence of the high affinity to the characteristic substrate Reactive Blue 5 the rPsaDyP belongs functionally to the dyp-type peroxidase family.

Hybrid mesoporous materials as carriers for immobilization of D-amino acid oxidase (DAAO) were prepared via three steps: (i) hydrothermal synthesis of nanoporous MCF, SBA-15 and MCM-41 powders, (ii) functionalization with 3-aminopropyltriethoxysilane (APTES) by post-synthesis grafting; and (iii) activation with glutardialdehyde. The resulting mesostructured solids were characterized by various techniques: XRD, IR, TGA-DTA and N2 adsorption–desorption (BET). The characterization results indicated that these materials still maintained their structure after functionalization. IR data and TGA-DTA analysis demonstrated the existence of amine functional groups on the surface of APTES-functionalized samples. The DAAO immobilized on these materials exhibited higher catalytic activity and stability of enzyme for conversion of cephalosporin C (CPC) as compared to those of the non-functionalized ones. The catalytic activity and stability of enzyme decreased in the order MCF > SBA-15 > MCM-41.

Background: With the rapid urbanization of Vietnam, living on boats has come to be associated with underprivileged socioeconomic status, and there are major concerns regarding the health of children living under such conditions. Bone development is a critical concern in children because the foundation for skeletal health is established early in life. We evaluated the bone properties of children living under underprivileged conditions on boats in Hue City, Vietnam, with respect to a number of household factors., Methods: One hundred and twenty children aged 7-11 years selected randomly from households living on boats in Hue were included in this study. Tibial and radial speed of sound (SOS) were measured by non-invasive quantitative ultrasonometry. Socioeconomic profiles, health promotion proficiency, and nutritional intake of households were assessed by structured interview. The bone properties of 60 children aged 7-11 living on land were also assessed as controls., Results: The Z-scores of tibial and radial SOS of boat children were -0.16 +/- 0.89 and -0.24 +/- 0.75 (mean +/- SD), respectively. Tibial SOS exhibited a significant correlation with radial SOS (r = 0.39, P < 0.01). Among the household factors examined, the educational level of fathers (P < 0.05) and the health promotion proficiency (P < 0.05) of households exhibited positive associations with the tibial bone properties of the children. The tibial and radial SOS of boat children were lower than those of children living on land (P = 0.001 and P = 0.086, respectively)., Conclusion: The results of the present study revealed the underdevelopment of bone properties in children living on houseboats, which was correlated with their living conditions.

Crosses between two species of the rodent genus Peromyscus produce defects in both growth and development. The defects are pronounced in the hybrid placentas. Peromyscuys maniculatus (strain BW) females mated to P. polionotus (strain PO) males produce placentas half the size of the parental species, as well as growth-retarded embryos. In contrast, PO females mated to BW males result in defective conceptuses that display embryonic and placental overgrowth. These 'parent-of-origin'-dependent phenotypes are consistent with previous studies that demonstrated altered expression of imprinted genes and genetic linkage of the overgrowth phenotypes to imprinted domains. In the present study, we take a broader approach in assessing perturbations in hybrid placental gene expression through the use of Mus musculus cDNA microarrays. In verifying classes of genes identified in microarray screens differentially regulated during hybrid placental development, we focused on those influencing the cell cycle and extracellular matrix (ECM). Our work suggests that cell cycle regulators at the G(1)/S phase check-point are downregulated in the large hybrid placenta, whereas the small hybrid placenta is more variable. The ECM genes are typically downstream targets of cell cycle regulation and their misregulation is consistent with many of the dysmorphic phenotypes. Thus, these data suggest imbalances in proliferation and differentiation in hybrid placentation.

Crosses between two recently diverged rodent species of the genus Peromyscus result in dramatic parent-of-origin effects on growth and development. P. maniculatus females crossed with P. polionotus males yield growth-retarded conceptuses, whereas the reciprocal cross results in overgrowth and lethality. These hybrid effects are particularly pronounced in the placenta. We previously detected linkage to two regions of the genome involved in the overgrowth effects. One locus, termed Peal, is a paternally expressed autosomal locus mapping to a domain whose house mouse equivalent contains several clusters of imprinted genes. The other locus, termed Mexl, maps to a gene-poor region of the X chromosome. Here we use an advanced intercross line to verify and narrow the regions of linkage and identify candidate genes for Mexl and Peal. While we have previously shown that Mexl affects both pre-and postnatal growth, we show here that Peal affects only prenatal growth. Utilizing criteria such as mutant phenotypes and allelic expression, we identify the loci encoding the homeobox protein Esx1 and the zinc-finger protein Pw1/Peg3 as candidates. Both loci exhibit expression changes in the hybrids.

With their genome sequenced, Anopheles gambiae mosquitoes now serve as a powerful tool for basic research in comparative, evolutionary and developmental biology. The knowledge generated by these studies is expected to reveal molecular targets for novel vector control and pathogen transmission blocking strategies. Comparisons of gene-expression profiles between adult male and nonblood-fed female Anopheles gambiae mosquitoes revealed that roughly 22% of the genes showed sex-dependent regulation. Blood-fed females switch the majority of their metabolism to blood digestion and egg formation within 3 h after the meal is ingested, in detriment to other activities such as flight and response to environment stimuli. Changes in gene expression are most evident during the first, second and third days after a blood meal, when as many as 50% of all genes showed significant variation in transcript accumulation. After laying the first cluster of eggs (between 72 and 96 h after the blood meal), mosquitoes return to a nongonotrophic stage, similar but not identical to that of 3-day-old nonblood-fed females. Ageing and/or the nutritional state of mosquitoes at 15 days after a blood meal is reflected by the down-regulation of approximately 5% of all genes. A full description of the large number of genes regulated at each analysed time point and each biochemical pathway or biological processes in which they are involved is not possible within the scope of this contribution. Therefore, we present descriptions of groups of genes displaying major differences in transcript accumulation during the adult mosquito life. However, a publicly available searchable database (http://www.angagepuci.bio.uci.edu/) has been made available so that detailed analyses of specific groups of genes based on their descriptions, functions or levels of gene expression variation can be performed by interested investigators according to their needs.

Female Anopheles gambiae mosquitoes respond to odours emitted from humans in order to find a blood meal, while males are nectar feeders. This complex behaviour is controlled at several levels, but is probably initiated by the interaction of various molecules in the antennal sensilla. Important molecules in the early odour recognition events include odourant binding proteins (OBPs), which may be involved in odour molecule transport, odourant receptors (ORs) that are expressed in the chemosensory neurones and odour degrading enzymes (ODEs). To obtain a better understanding of the expression patterns of genes that may be involved in host odour reception in females, we generated a custom microarray to study their steady state mRNA levels in chemosensory tissues, antennae and palps. These results were supported by quantitative RT PCR. Our study detected several OBPs that are expressed at significantly higher levels in antennae and palps of females vs. males, while others showed the opposite expression pattern. Most OBPs are slightly down-regulated 24 h after blood feeding, but some, especially those with higher expression levels in males, are up-regulated in blood-fed females, suggesting a shift in blood-fed females from human host seeking to nectar feeding.

A microarray analysis of 14 900 genes of the malaria vector mosquito, Anopheles gambiae, shows that as many as 33% (4924) of their corresponding transcription products vary in abundance within 24 h after a blood meal. Approximately half (2388) of these products increase in their accumulation and the remainder (2536) decrease. Expression dynamics of 80% of the genes analysed by expressed sequence tag (EST) projects reported previously are consistent with the observations from this microarray analysis. Furthermore, the microarray analysis is more sensitive in detecting variation in abundance of gene products expressed at low levels and is more sensitive overall in that a greater number of regulated genes are detected. Major changes in transcript abundance were seen in genes encoding proteins involved in digestion, oogenesis and locomotion. The microarray data and an electronic hyperlinked version of all tables are available to the research community at http://www.angagepuci.bio.uci.edu/1/.

Hutchinson-Gilford progeria syndrome is a rare syndrome of premature aging with multiple skeletal abnormalities. We report one case. The literature is reviewed. Characteristics of 30 patients with radiological records are presented. Pronounced acro-osteolysis, osteolysis of the clavicle are the main features. Modern imaging is useful to diagnose the complications.

We report a new case of tracheo-bronchial tuberculosis. Diagnosis was suggested on CT examination first and then confirmed by endoscopy and bacteriological examinations. We discuss the possible mechanisms of stenosis. We present the radiological features of tracheo-bronchial tuberculosis, mainly helical CT features and we discuss and illustrate differential diagnosis. We emphasize the role of 3 D and multiplanar reconstructed CT images that may help visualizing the stenosis at different levels, its craniocaudal extent as well as the boundaries between the stenosis and surrounding tissues. Moreover helical CT appears superior to bronchofibroscopy in diagnosing peribronchial infiltration.

Appendicitis is a frequently encountered surgical emergency which can be diagnosed by clinical and laboratory criteria. But there are some atypical cases that ultrasound can help to diagnose. From April the 9th 1992 to April the 11th 1993, we have examined by ultrasound 465 patients entered in our hospital for right lower quadrant pain. 190 patients have been diagnosed as appendicitis and operated (true positive = 124 cases, false negative = 54 cases and false positive = 12 cases). 275 patients have been diagnosed as negative and they are not operated (true = 273 cases, false positive = 2 cases). So in our study, the sensitivity is 70%, the specificity is 95% and the accuracy is 85%. Our scientific report has the objective to show the usefulness and the limits of ultrasound in the diagnosis of appendicitis.