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This study presents a tri-layer broadband metamaterial absorber that operates in the GHz range. The absorber was composed of a polyhedral iron-cobalt alloy/graphite nanosheet material arranged in a flat sheet with two punched-in rings for the top layer, a continuous FR-4 layer at the middle, and a continuous copper layer at the bottom. For the normal incidence of the electromagnetic wave, the proposed absorber demonstrated an exceptional broadband absorption in a frequency range of 7.9–14.6 GHz, revealing an absorption exceeding 90%. The absorption magnitude remains to be above 90% in a frequency range of 8–11.1 GHz for transverse-electric-polarized waves at incident angles up to 55°. For both the transverse-magnetic- and electric-polarized waves, the absorption exceeds 90% in a frequency range of 9.5–14.6 GHz. The physical mechanism behind the absorption properties is analyzed thoroughly through the electric and magnetic field distributions. The obtained results could contribute potentially to the development of microwave applications based on metamaterial absorbers, such as radar-stealth technology, electromagnetic shielding for health safety, and reduced electromagnetic interferences for high-performance communications and electronic devices.

Background and aimsVitamin C, as an antioxidant, may play a role in the treatment of NAFLD. This research aimed to investigate the association of serum vitamin C levels with the risk of NAFLD and to further examine the causal relationship by Mendelian randomization (MR) method.MethodsThe cross-sectional study selected 5,578 participants of the National Health and Nutrition Examination Survey (NHANES), 2005–2006 and 2017–2018. The association of serum vitamin C levels with NAFLD risk was evaluated under a multivariable logistic regression model. A two-sample MR study, using genetic data from large-scale genome-wide association studies (GWAS) of serum vitamin C levels (52,014 individuals) and NAFLD (primary analysis: 1,483 cases /17,781 controls; secondary analysis: 1,908 cases/340,591 controls), was conducted to infer causality between them. The inverse-variance-weighted (IVW) was applied as the main method of MR analysis. A series of sensitivity analyzes were used to evaluate the pleiotropy.ResultsIn the cross-sectional study, results showed that Tertile 3 group (Tertile 3: ≥1.06 mg/dl) had a significantly lower risk (OR = 0.59, 95% CI: 0.48 ~ 0.74, p p p = 0.029) but was stronger among women. However, in the IVW of MR analyzes, no causal relationship between serum vitamin C levels and NAFLD risk was observed in the primary analysis (OR = 0.82, 95% CI: 0.47 ~ 1.45, p = 0.502) and secondary analysis (OR = 0.80, 95% CI: 0.53 ~ 1.22, p = 0.308). MR sensitivity analyzes yielded consistent results.ConclusionOur MR study did not support a causal association between serum vitamin C levels and NAFLD risk. Further studies with greater cases are warranted to confirm our findings.

Self-attention modules have demonstrated remarkable capabilities in capturing long-range relationships and improving the performance of point cloud tasks. However, point cloud objects are typically characterized by complex, disordered, and non-Euclidean spatial structures with multiple scales, and their behavior is often dynamic and unpredictable. The current self-attention modules mostly rely on dot product multiplication and dimension alignment among query-key-value features, which cannot adequately capture the multi-scale non-Euclidean structures of point cloud objects. To address these problems, this paper proposes a self-attention plug-in module with its variants, Multi-scale Geometry-aware Transformer (MGT). MGT processes point cloud data with multi-scale local and global geometric information in the following three aspects. At first, the MGT divides point cloud data into patches with multiple scales. Secondly, a local feature extractor based on sphere mapping is proposed to explore the geometry inner each patch and generate a fixed-length representation for each patch. Thirdly, the fixed-length representations are fed into a novel geodesic-based self-attention to capture the global non-Euclidean geometry between patches. Finally, all the modules are integrated into the framework of MGT with an end-to-end training scheme. Experimental results demonstrate that the MGT vastly increases the capability of capturing multi-scale geometry using the self-attention mechanism and achieves strong competitive performance on mainstream point cloud benchmarks.

Additional file 1: Figure. S1. A flowchart summarizing the study. Figure S2. Distinct cellular construction of primary and metastatic samples. Figure S3. Cellular hierarchy of malignant cell including nine clusters. Figure S4. Volcano plot showing expression of DEGs (|logFC|>1 and adjusted P

Recently, 3D object detection has attracted significant attention and achieved continuous improvement in real road scenarios. The environmental information is collected from a single sensor or multi-sensor fusion to detect interested objects. However, most of the current 3D object detection approaches focus on developing advanced network architectures to improve the detection precision of the object rather than considering the dynamic driving scenes, where data collected from sensors equipped in the vehicle contain various perturbation features. As a result, existing work cannot still tackle the perturbation issue. In order to solve this problem, we propose a group equivariant bird's eye view network (GeqBevNet) based on the group equivariant theory, which introduces the concept of group equivariant into the BEV fusion object detection network. The group equivariant network is embedded into the fused BEV feature map to facilitate the BEV-level rotational equivariant feature extraction, thus leading to lower average orientation error. In order to demonstrate the effectiveness of the GeqBevNet, the network is verified on the nuScenes validation dataset in which mAOE can be decreased to 0.325. Experimental results demonstrate that GeqBevNet can extract more rotational equivariant features in the 3D object detection of the actual road scene and improve the performance of object orientation prediction., Comment: 8 pages,3 figures

Autoencoders have achieved great success in various computer vision applications. The autoencoder learns appropriate low dimensional image representations through the self-supervised paradigm, i.e., reconstruction. Existing studies mainly focus on the minimizing the reconstruction error on pixel level of image, while ignoring the preservation of Intrinsic Dimension (ID), which is a fundamental geometric property of data representations in Deep Neural Networks (DNNs). Motivated by the important role of ID, in this paper, we propose a novel deep representation learning approach with autoencoder, which incorporates regularization of the global and local ID constraints into the reconstruction of data representations. This approach not only preserves the global manifold structure of the whole dataset, but also maintains the local manifold structure of the feature maps of each point, which makes the learned low-dimensional features more discriminant and improves the performance of the downstream algorithms. To our best knowledge, existing works are rare and limited on exploiting both global and local ID invariant properties on the regularization of autoencoders. Numerical experimental results on benchmark datasets (Extended Yale B, Caltech101 and ImageNet) show that the resulting regularized learning models achieve better discriminative representations for downstream tasks including image classification and clustering.

Identification of pnemococcal serotypes and antimicrobial resistance provides helpful information for the use of suitable vaccines and antibiotics; however, very limited data is available on these issues in Vietnam. The present study aimed to find the serotype distribution and drug resistance patterns ofA total of 126 clinical pnemococcal strains isolated from unvaccinated children less than 5 years of age with pneumonia at the Nghe An province, Vietnam between Nov 2019 and Mar 2021. All strains were identified using conventional microbiological method, VITEK® 2 Compact system, specific PCR and sequencing. The serotypes and antimicrobial resistance patterns of pnemococcal strains were determined using the multiplex PCR assays and VITEK® 2 Compact system.The results showed that, eight different pneumococcal serotypes were identified. The most common serotypes were 19F (67.46%), followed by 23F (10.32%), 19A (9.52%), 6A/B (3.17%), 15A (2.38%), 9V (3.17%), 11A (1.59%) and 14 (0.80%), respectively. More than half of the pneumococcal strains were non-susceptible to penicillin. The resistance rate to ceftriaxone and cefotaxime were 41.3% and 50.8%. The percentage of pneumococci strains resistant to clarithromycin, azithromycin, erythromycin, cotrimoxazole, tetracyclin, and clindamycin were more than 93% of all strains. All pneumococcal serotypes were highly resistant to clarithromycin, azithromycin, erythromycin, cotrimoxazole, and clindamycin.Our findings showed high antibiotic resistance rates of the strains causing pneumococcal pneumonia, mostly macrolide resistance, among unvaccinated children.

Background and Objectives: Identification of pnemococcal serotypes and antimicrobial resistance provides helpful infor- mation for the use of suitablevaccines and antibiotics; however, very limited data is available on these issues in Vietnam. The present study aimed to find the serotype distribution and drugresistance patterns of Streptococcus pneumoniae isolated from unvaccinated children less than 5 years of age with pneumonia at a province in centre Vietnam. Materials and Methods: A total of 126 clinical pnemococcal strains isolated from unvaccinated children less than 5 years of age with pneumonia at theNghe An province, Vietnam between Nov 2019 and Mar 2021. All strains were identified using conventional microbiological method, VITEK® 2 Compactsystem, specific PCR and sequencing. The serotypes and antimicrobial resistance patterns of pnemococcal strains were determined using the multiplex PCRassays and VITEK® 2 Compact system. Results: The results showed that, eight different pneumococcal serotypes were identified. The most common serotypes were 19F (67.46%), followed by23F (10.32%), 19A (9.52%), 6A/B (3.17%), 15A (2.38%), 9V (3.17%), 11A (1.59%) and 14 (0.80%), respectively. More than half of the pneumococcal strainswere non-susceptible to penicillin. The resistance rate to ceftriaxone and cefotaxime were 41.3% and 50.8%. The percentage of pneumococci strains resistantto clarithromycin, azi- thromycin, erythromycin, cotrimoxazole, tetracyclin, and clindamycin were more than 93% of all strains. All pneumococcal serotypes were highly resistant to clarithromycin, azithromycin, erythromycin, cotrimoxazole, and clindamycin. Conclusion: Our findings showed high antibioticresistance rates of the strains causing pneumococcal pneumonia, mostly macrolide resistance, among unvaccinated children.

To explore the presence of aflatoxin B1 (AFB1) and fungi in traditional drugs collected in Vietnam. Materials and Methods: 505 samples of 88 different traditional drugs were obtained from 10 hospitals in Nghe An, a central province of Vietnam. AFB1 contamination was determined by a high-performance liquid chromatography (HPLC) assay. Fungal contaminants were determined according to WHO regulations, and the obtained Aspergillus strains were characterized via morphological and molecular identification. Results: 24 samples (4.75% of the total samples) were contaminated with AFB1, and the average concentration was 0.062±0.030 µg/kg (ranging from 0.009 to 0.097 µg/kg). Fungal isolates were detected from 174 samples (34.45%). The genus Aspergillus was predominant (82.76% of the isolates), but Rhizopus, Alternaria, Corynespora, and yeast were also found in a few samples. Among 144 strains of Aspergillus recovered, A. niger (105 strains) was most frequently found, followed by A. tubingensis (31 strains), A. oryzae (4 strains), and A. flavus (4 strains). Conclusion: This study suggests a low risk of aflatoxin B1 exposure to consumers of traditional drugs in Vietnam.

Background and Purpose: Burn injuries are prone to infection caused by bacteria, fungi, or other pathogens. Fungal wound infection usually has non-specific clinical symptoms.Nevertheless, in some cases, the fungal burden is so substantial that can easily be seen by the naked eyes, but this phenomenon has rarely been reported with Fusarium. Case report: A 53-year-old patient with severe burn injury was admitted to the intensive care unit of the National Hospital of Burn, Ha Noi, Vietnam. His wound was dressed with a traditional herbal product before the hospital admission. On the 5th day after the admission, some white patches suspected of fungal colonies appeared on burn lesions where the herbal medicine was placed. Histological examination (Periodic acidSchiff) and culture of biopsy samples taken from those lesions revealed fungus that was identified as Fusarium equiseti after analysis of the internal transcribed spacer and D1/D2 region of the large subunit of the 28S rDNA. The isolated strain showed susceptibility to voriconazole but resistance to fluconazole, itraconazole, caspofungin,and amphotericin B in vitro. The patient received aggressive treatment, including IV voriconazole (400 mg daily from day five); however, he could not recover. Conclusion: Fusarium should be suspected in burn patients with white patches on lesions. Antifungal susceptibility testing is important since multidrug resistance is common among Fusarium strains.

To support the industrial design and process development for the separation of xylenol isomers from coal tar, the present work was focused on 2,4/2,5-xylenol mixture as 2,4-xylenol and 2,5-xylenol have very close boiling points. Specifically, the kinetics of the alkylation of 2,4/2,5-xylenol mixture was investigated that formed the first step of the alkylation-distillation-dealkylation separation strategy. By quantifying the influence of various key factors on the reaction rate, the rate equations of 2,4-xylenol and 2,5-xylenol alkylation were determined as $${{r}_{{2,4}}} = 1538{{e}^{{{{ - 39{\kern 1pt} 360} \mathord{\left/ {\vphantom {{ - 39{\kern 1pt} 360} {RT}}} \right. \kern-0em} {RT}}}}}c_{{2,4}}^{{1.1}}P_{{{\text{PIB}}}}^{{1.0}}c_{{{\text{PTSA}}}}^{{0.4}}$$ and $${{r}_{{2,5}}} = 516{{e}^{{{{ - 32{\kern 1pt} 241} \mathord{\left/ {\vphantom {{ - 32{\kern 1pt} 241} {RT}}} \right. \kern-0em} {RT}}}}}c_{{2,5}}^{{1.0}}P_{{{\text{PIB}}}}^{{0.8}}c_{{{\text{PTSA}}}}^{{0.7}}{\text{,}}$$ respectively. The alkylation rate of 2,4-xylenol was notably higher than that of 2,5-xylenol. The influence of temperature, xylenol concentration and isobutylene partial pressure on the reaction rate of 2,4-xylenol was also greater than that of 2,5-xylenol, whilst the influence of catalyst dosage on the alkylation rate of 2,5-xylenol was found to be greater than that of 2,4-xylenol. The results can be potentially used for reactor design and process development for the separation of 2,4/2,5-xylenol mixture from coal tar.

The phytochemical constituents from the roots of Millettia speciosa were investigated by chromatographic isolation, and their chemical structures were characterized using the MS and NMR spectroscopic methods. A total of 10 compounds, including six triterpenoids, two flavonoids, and two phenolic compounds, were identified from the roots of M. speciosa. Out of the isolated compounds, eight showed inhibitory effects on NO production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, with IC50 values ranging from 43.9 to 449.5 µg/mL. Ursane-type triterpenes significantly suppressed NO production compared to the remaining compounds. In addition, these compounds also exhibited remarkable inhibitory effects on α-glucosidase. Among the tested compounds, 4, 5, and 10 exhibited excellent α-glucosidase inhibition, with IC50 values ranging from 1.1 to 2.2 µg/mL. Almost all of the test compounds showed little or no acetylcholinesterase inhibition, except for 5, which showed moderate anti-acetylcholinesterase activity in vitro. The molecular docking study of α-glucosidase inhibition by 3–5 and 10 was conducted to observe the interactions of these molecules with the enzyme. Compounds 4, 5, and 10 exhibited a better binding affinity toward the targeted receptor and the H-bond interactions located at the entrance of the enzyme active site pocket in comparison to those of 3 and the positive control acarbose. Our findings evidence the pharmacological potential of this species and suggest that the phytochemicals derived from the roots of M. speciosa may be promising lead molecules for further studies on the development of anti-inflammatory and anti-diabetes drugs.

Adversarial attacks are often considered as threats to the robustness of Deep Neural Networks (DNNs). Various defending techniques have been developed to mitigate the potential negative impact of adversarial attacks against task predictions. This work analyzes adversarial attacks from a different perspective. Namely, adversarial examples contain implicit information that is useful to the predictions i.e., image classification, and treat the adversarial attacks against DNNs for data self-expression as extracted abstract representations that are capable of facilitating specific learning tasks. We propose an algorithmic framework that leverages the advantages of the DNNs for data self-expression and task-specific predictions, to improve image classification. The framework jointly learns a DNN for attacking Variational Autoencoder (VAE) networks and a DNN for classification, coined as Attacking VAE for Improve Classification (AVIC). The experiment results show that AVIC can achieve higher accuracy on standard datasets compared to the training with clean examples and the traditional adversarial training.

The phytochemical constituents from the roots of

Background: Human toxocariasis is prevalent in many countries but this disease has been rarely reported from Vietnam. We aimed to investigate the clinical and laboratory findings and assess possible association between these findings in patients with toxocariasis in Vietnam. Methods: A prospectively study, between October 2017 and June 2019 was performed involving 120 toxocariasis patients at Medic Medical Center, Ho Chi Minh City, Vietnam. The diagnosis of toxocariasis was established based on clinical, laboratory (eosinophilia, raised IgE concentration) and serological (positive Toxocara IgG ELISA test) evaluation as well as the exclusion of other helminthic coinfection. Results: The most frequently reported manifestation was of skin (n = 93, 77.5%), including urticarial (n= 69, 57.5%) followed by neurologic, gastrointestinal and pulmonary signs/symptoms. Hepatic involvement occurred in 8.3% of the patients. No significant relationship between clinical findings and laboratory parameters was found except the higher values of eosinophil count and IgE concentration among patients with liver involvement. There was a significant relationship between eosinophil count and IgE concentration (r=0.389, P

Objectives Human toxocariasis is a widespread zoonosis for which a chemotherapy decision and therapy effectiveness are difficult to determine. We aimed to investigate the kinetic profile of clinical and laboratory findings and treatment outcome of patients with toxocariasis in Vietnam. Methods The prospective study was conducted between October 2017 and June 2019. The diagnosis of toxocariasis was established based on clinical, laboratory (eosinophilia, raised IgE concentration) and serological (positive Toxocara IgG ELISA) evaluation as well as the exclusion of another helminthic coinfection. The patients were followed up after seven days, then one, three, and six months after chemotherapy by thiabendazole. Results The study involved 80 patients with a mean age of 41.6 ± 15.2 years of whom 58.8% were female. At three and six months after chemotherapy, most patients demonstrated resolution of clinical signs and symptoms, eosinophil count and IgE concentration but not in the proportion of IgG seropositivity. Skin lesions and eosinophilia resolved earlier than the other symptoms (one month after treatment). About four-fifths of the patients were "cured" after three and six months of follow-up. 33.8% showed side effects to thiabendazole therapy but no severe events were reported. The most common adverse reaction was neurologic symptoms followed by gastrointestinal or skin manifestations which lasted as long as 4 days. Conclusions In toxocariasis patients, cutaneous manifestations and eosinophilia resolve more rapidly than other clinical and laboratory findings while IgG titre has a very slow kinetic after therapy. Thiabendazole seems to be a potential alternative for the treatment of human toxocariasis.

The most recent year has witnessed the success of applying the Vision Transformer (ViT) for image classification. However, there are still evidences indicating that ViT often suffers following two aspects, i) the high computation and the memory burden from applying the multiple Transformer layers for pre-training on a large-scale dataset, ii) the over-fitting when training on small datasets from scratch. To address these problems, a novel method, namely, Vision Reservoir computing (ViR), is proposed here for image classification, as a parallel to ViT. By splitting each image into a sequence of tokens with fixed length, the ViR constructs a pure reservoir with a nearly fully connected topology to replace the Transformer module in ViT. Two kinds of deep ViR models are subsequently proposed to enhance the network performance. Comparative experiments between the ViR and the ViT are carried out on several image classification benchmarks. Without any pre-training process, the ViR outperforms the ViT in terms of both model and computational complexity. Specifically, the number of parameters of the ViR is about 15% even 5% of the ViT, and the memory footprint is about 20% to 40% of the ViT. The superiority of the ViR performance is explained by Small-World characteristics, Lyapunov exponents, and memory capacity., Comment: 10 pages, 7 figures

With the proliferation of mobile devices and the Internet of Things, deep learning models are increasingly deployed on devices with limited computing resources and memory, and are exposed to the threat of adversarial noise. Learning deep models with both lightweight and robustness is necessary for these equipments. However, current deep learning solutions are difficult to learn a model that possesses these two properties without degrading one or the other. As is well known, the fully-connected layers contribute most of the parameters of convolutional neural networks. We perform a separable structural transformation of the fully-connected layer to reduce the parameters, where the large-scale weight matrix of the fully-connected layer is decoupled by the tensor product of several separable small-sized matrices. Note that data, such as images, no longer need to be flattened before being fed to the fully-connected layer, retaining the valuable spatial geometric information of the data. Moreover, in order to further enhance both lightweight and robustness, we propose a joint constraint of sparsity and differentiable condition number, which is imposed on these separable matrices. We evaluate the proposed approach on MLP, VGG-16 and Vision Transformer. The experimental results on datasets such as ImageNet, SVHN, CIFAR-100 and CIFAR10 show that we successfully reduce the amount of network parameters by 90%, while the robust accuracy loss is less than 1.5%, which is better than the SOTA methods based on the original fully-connected layer. Interestingly, it can achieve an overwhelming advantage even at a high compression rate, e.g., 200 times., Comment: 18 pages, 5figures

Tien Hiep Nguyen1, htnru7@yandex.ru, Nguyen Van Minh2, chinhnhan88@gmail.com, Tang Viet Phuong3, sirtang83@gmail.com, Tang Xuan Duong4, duongvampire@mail.ru, Le Hong Quan4, quanttndvn@gmail.com 1 Le Quy Don Technical University, Hanoi, Vietnam, 2 Institute of Technology, Hanoi, Vietnam, 3 National University of Science and Technology “MISiS”, Moscow, Russian Federation 4 Vietnam-Russia Tropical Centre, Hanoi, Vietnam Тиен Хиеп Нгуен, лектор, Государственный технический университет им. Ле Куй Дона, г. Ханой, Вьетнам; htnru7@yandex.ru. Нгуен Ван Минь, канд. техн. наук, Технологический институт, г. Ханой, Вьетнам; chinhnhan88@gmail.com. Танг Вьет Фыонг, аспирант, Национальный исследовательский технологический университет «МИСиС», г. Москва; sirtang83@gmail.com. Танг Суан Зыонг, исследователь, Российско-Вьетнамский тропический центр, г. Ханой, Вьетнам; duongvampire@mail.ru. Ле Хонг Куан, исследователь, Российско-Вьетнамский тропический центр, г. Ханой, Вьетнам; quanttndvn@gmail.com In this work, the process of obtaining magnetite nanopowder Fe3O4 by hydrogen reduction from α-FeOOH hydroxide compound under isothermal conditions was studied. The α-FeOOH nanopowder was prepared in advance by chemical precipitation from aqueous solutions of iron nitrate Fe(NO₃)₃ (10 wt. %) and alkali NaOH (10 wt. %) at room temperature, pH = 11, under the condition of continuous stirring. The hydrogen reduction process of α-FeOOH powder under isothermal conditions was carried out in a tube furnace in the temperature range from 310 to 375 °С. The study of the crystal structure and phase composition of the powder samples was performed by XRD phase analysis. The specific surface area S of the samples was measured using BET method by lowtemperature nitrogen adsorption. The average particle size D of powders was calculated using the data of measuring the specific surface area S. The size and morphology characteristics of the particles were investigated by scanning and transmission electron microscopy method. The calculation of the kinetic parameters of the process of obtaining the Fe₃O₄ nanopowder under isothermal conditions was carried out using the Gray–Weddington model and the Arrhenius equation. It was found that the reduction process of the α-FeOOH nanopowder begins to accelerate strongly in the temperature range from 340 to 375 °С. The reduction rate constant at 375 °С is about 2 times that of the reduction at 310 °С. The value of the activation energy for the process of obtaining Fe3O4 nanopowder under isothermal conditions was ~ 36 kJ/mol, which indicates a mixed mode of limiting the kinetics of the process. It has been shown that the time-temperature regime of the reduction of the α-FeOOHhydroxide compound with holding at 340 °С for 3 h makes it possible to obtain a nanosized magnetite powder Fe₃O₄ with high purity at an increased rate of the process. The obtained Fe₃O₄ nanoparticles have a crystalline structure and generally have a polygonal or irregular shape, the size of which ranges from 30–80 nm with an average value of 65 nm, each of them being connected to several neighboring particles by isthmuses. В данной работе проведено изучение процесса получения нанопорошка магнетита Fe₃O₄ водородным восстановлением гидроксидного соединения α-FeOOH в изотермических условиях. Нанопорошок α-FeOOH заранее получали методом химического осаждения из водных растворов нитрата железа Fe(NO₃)₃ (10 мас. %) и щелочи NaOH (10 мас. %) при комнатной температуре, рН = 11, при условии непрерывного перемешивания. Процесс водородного восстановления порошка α-FeOOH в изотермических условиях проводили в трубчатой печи в интервале температур от 310 до 375 °С. Исследование кристаллической структуры и фазового состава образцов порошков выполняли методом рентгенофазового анализа. Удельную поверхность S образцов измеряли методом БЭТ по низкотемпературной адсорбции азота. Средний размер частиц D рассчитали по данным измерения величины удельной поверхности. Размерные характеристики и морфологию частиц порошков изучали методом сканирующей и просвечивающей электронной микроскопии. Расчет кинетических параметров процесса получения нанопорошка Fe₃O₄ в изотермических условиях проводили с помощью модели Грея – Веддингтона и уравнения Аррениуса. Установлено, что процесс восстановления нанопорошка α-FeOOН начинает сильно ускоряться в интервале температур от 340 до 375 °С. Константа скорости восстановления при 375 °С примерно в 2 раза больше, чем в случае восстановления при 310 °С. Величина энергии активации процесса получения нанопорошка Fe₃O₄ в изотермических условиях составила ~ 36 кДж/моль, что говорит о смешанном режиме лимитирования кинетики процесса. Показано, что временно-температурный режим восстановления гидроксидного соединения α-FeOOН с выдержкой при 340 °С в течение 3 ч позволяет получить наноразмерный порошок магнетита Fe₃O₄ с высокой чистотой при повышенной скорости процесса. Полученные наночастицы Fe₃O₄ обладают кристаллической структурой и в основном имеют многоугольную или неправильную форму, их размер составляет 30–80 нм со средним значением 65.

Interval computation is widely used to certify computations that use floating point operations to avoid pitfalls related to rounding error introduced by inaccurate operations. Despite its popularity and practical benefits, support for interval arithmetic is not standardized nor available in mainstream programming languages. We propose the first benchmark for interval computations, coupled with reference solutions computed with exact arithmetic, and compare popular C and C++ libraries over different architectures, operating systems, and compilers. The benchmark allows identifying limitations in existing implementations, and provides a reliable guide on which library to use on each system. We believe that our benchmark will be useful for developers of future interval libraries, as a way to test the correctness and performance of their algorithms., Comment: 11 pages, 33 figures, 2 tables

This paper reported a new record of Orchidaceae from Guangxi, Galeola nudifolia Lour. This species was previously known from Hainan Province and Yunnan Province of China, India, Myanmar, Vietnam, Thailand, Malaysia, Indonesia and the Philippines. The new Orchidaceae record has broken the record of only one species of the genus Galeola Lour. in Guangxi, and it filled the gap in the northern part of the original distribution area, and proved that the species in general is in a continuous distribution state. The new Orchidaceae record in Guangxi is of great significance to the study of the distribution pattern and geographical origin of the species.

Additional file 1. Patient clinical outcomes for Biqi and LEF treatment arms in the PP analysis.

In order to make reasonable use of collected and preserved Dendrobium germplasm resources, ISSR molecular marker method was used to analyze the genetic relationship and genetic diversity of 22 Dendrobium species. A total of 6 primers with clear amplification bands, high polymorphism and good repeatability were chosen from 100 ISSR primers. The selected primers were used to amplify the genomic DNA of 22 Dendrobium species by PCR, and a total of 241 bands were generated, of which 241 were polymorphic bands. Polymorphic ratio was 100%. By GenAlEx 6.5 software, average value of observed allele number, effective number of alleles, Nei's gene diversity and Shannon's information index was 1.983, 1.167, 0.133 and 0.247, respectively, indicating that a high level of genetic diversity among 22 Dendrobium species. The genetic similarity coefficient among 22 Dendrobium species ranged from 0.698 4 to 0.878 7 by NTSYS-pc 2.1 software. UPGMA clustering based on genetic similarity coefficient, 22 Dendrobium species could be divided into 10 groups when genetic similarity was 0.795. UPGMA clustering results are consistent with traditional morphological classification results. The DNA fingerprint map constructed with 3 pairs of primers can separately identify 22 Dendrobium species. This research laid a theoretical foundation for the identification of Dendrobium germplasm resources and the selection of parents for cross breeding.

Research on formulation of nanosilver-infused cream was carried out at the Institute of Environmental Technology and the effects of this cream in prevention and treatment of mastitis in dairy cows were assessed at Bavi Cattle and Forage Research Center. Cream with 0.4% carbomer was infused with silver nanoparticles for high uniformity and long-term stability. At concentrations of 50–250 ppm, nanosilver-infused cream proved to be effective against mastitis pathogens such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa. Nanosilver cream at concentrations of 150 ppm had the best effect on clinical and subclinical mastitis prevention in dairy cows. Combining nanosilver cream with ceftiofer antibiotic achieved excellent treatment rate, up to 93.33%. For prevention of dairy mastitis, silver cream can be used at a concentration of 150 ppm 15 days before calving and for the whole milking period. Using nanosilver cream in combination with antibiotics led to highly effective mastitis treatment.

Free-space optical communications (FSO) suffers from irradiance fluctuation caused by atmospheric turbulence, which results in optical power loss and consequently decreased signal-to-noise ratio (SNR). The error performances of the FSO based on On-Off Keying (OOK), Differential Phase Shift Keying (DPSK), and Binary Phase Shift Keying (BPSK) schemes in a turbulent atmosphere are presented. The received irradiance after propagating the atmosphere is modeled using the gamma-gamma distribution to evaluate the system error performance in turbulence regimes from weak to strong. The results show that, to obtain a BER of 10-6 at weak turbulence regime, ~15 dB and ~18 dB SNRs are required for BPSK and DPSK, respectively. However, for OOK with a fixed threshold of 0.5 under the same channel condition, OOK reaches an error floor greater than 10-3. The values of SNR required to achieve the same BER increase as the turbulence strength increase to moderate and strong regimes.

Recently, convolutional neural networks (CNNs) have achieved excellent performances in many computer vision tasks. Specifically, for hyperspectral images (HSIs) classification, CNNs often require very complex structure due to the high dimension of HSIs. The complex structure of CNNs results in prohibitive training efforts. Moreover, the common situation in HSIs classification task is the lack of labeled samples, which results in accuracy deterioration of CNNs. In this work, we develop an easy-to-implement capsule network to alleviate the aforementioned problems, i.e., 1D-convolution capsule network (1D-ConvCapsNet). Firstly, 1D-ConvCapsNet separately extracts spatial and spectral information on spatial and spectral domains, which is more lightweight than 3D-convolution due to fewer parameters. Secondly, 1D-ConvCapsNet utilizes the capsule-wise constraint window method to reduce parameter amount and computational complexity of conventional capsule network. Finally, 1D-ConvCapsNet obtains accurate predictions with respect to input samples via dynamic routing. The effectiveness of the 1D-ConvCapsNet is verified by three representative HSI datasets. Experimental results demonstrate that 1D-ConvCapsNet is superior to state-of-the-art methods in both the accuracy and training effort.

There are some inadequacies in the language description of this paper that require further improvement. This paper is based on a revision of a conference paper. It is now necessary to further explain the difference between the contributions of the two papers., Comment: Some inappropriate descriptions have been found in this paper

Dendrobium nestor is a famous orchid species in the Orchidaceae family. There is a diversity of flower colorations in the Dendrobium species, but knowledge of the genes involved and molecular mechanism underlying the flower color formation in D. nestor is less studied. Therefore, we performed transcriptome profiling using Illumina sequencing to facilitate thorough studies of the purple color formation in petal samples collected at three developmental stages, namely—flower bud stage (F), half bloom stage (H), and full bloom stage (B) in D. nestor. In addition, we identified key genes and their biosynthetic pathways as well as the transcription factors (TFs) associated with purple flower color formation. We found that the phenylpropanoid–flavonoid–anthocyanin biosynthesis genes such as phenylalanine ammonia lyase, chalcone synthase, anthocyanidin synthase, and UDP-flavonoid glucosyl transferase, were largely up-regulated in the H and B samples as compared to the F samples. This upregulation might partly account for the accumulation of anthocyanins, which confer the purple coloration in these samples. We further identified several differentially expressed genes related to phytohormones such as auxin, ethylene, cytokinins, salicylic acid, brassinosteroid, and abscisic acid, as well as TFs such as MYB and bHLH, which might play important roles in color formation in D. nestor flower. Sturdy upregulation of anthocyanin biosynthetic structural genes might be a potential regulatory mechanism in purple color formation in D. nestor flowers. Several TFs were predicted to regulate the anthocyanin genes through a K-mean clustering analysis. Our study provides valuable resource for future studies to expand our understanding of flower color development mechanisms in D. nestor.

Habenaria rhodocheila is different from other species in the genus as it has bright yellow-orange, orange-red or red floral colors and grows in subtropical evergreen broad-leaved forests. It is listed as a level II protected plant in China. This study focused on details of the pollination mechanism, including floral structure, the pollinator and its behavior, the pollination process, and fruit set in its natural environment compared to controlled artificial pollination. Our results showed that the flowers of H. rhodocheila are self-compatible, but rely on a pollinating agent due to the lack of an automatic self-pollination mechanism. At three sites the flowers of H. rhodocheila were frequently pollinated by a species of the swallowtail butterfly Papilio helenus L. During pollination, the butterfly inserts its proboscis into the spur aperture. The base of the proboscis then contacts the viscidia and the pollinarium sticks to the insect, followed by contact between pollinia and stigmas. The length of the proboscis of P. helenus is comparable to, but slightly shorter than the length of the floral spur. The pollination activity generally occurs between 9:30 AM to 1:30 PM daily and is especially frequent between 10:30 AM and 11:30 AM. These results suggest that the similarity between the length of the butterfly's proboscis and the length of the orchid's spur is a major factor contributing to the efficient pollination of H. rhodocheila in its natural habitat. Most species in Habenaria are moth-pollinated, whereas our research has shown that H. rhodocheila in subtropical evergreen broad-leaved forests in China is specifically adapted to butterfly pollination by P. helenus.

Plantaricin NC8, a two-peptide non-lantibiotic class IIb bacteriocin composed of PLNC8α and PLNC8β and derived from Lactobacillus plantarum ZJ316, has been shown to be highly potent against a range of bacteria and fungi. In this study, we assessed the antimicrobial mechanism of plantaricin NC8 against the most sensitive bacterial strain, Micrococcus luteus CGMCC 1.193. The results showed that plantaricin NC8 induced membrane permeabilization and caused cell membrane disruption to M. luteus CGMCC 1.193 cells, as evidenced by electrolyte efflux, loss of proton motive force, and ATP depletion within a few minutes of plantaricin NC8 treatment. Furthermore, scanning and transmission electron microscopy showed that plantaricin NC8 had a drastic impact on the structure and integrity of M. luteus CGMCC 1.193 cells. In addition, we found that either PLNC8α or PLNC8β alone exhibited membrane permeabilization activity, but that PLNC8β had higher permeabilization activity, and their individual effects were not as strong as that of the combined compounds as plantaricin NC8. Finally, we showed that lipid II is not the specific target of plantaricin NC8 against M. luteus CGMCC 1.193. Our study reveals the antimicrobial mechanism of plantaricin NC8 against M. luteus CGMCC 1.193.

Plantaricin NC8, a two-peptide non-lantibiotic class IIb bacteriocin composed of PLNC8α and PLNC8β and derived from Lactobacillus plantarum ZJ316, has been shown to be highly potent against a range of bacteria and fungi. In this study, we assessed the antimicrobial mechanism of plantaricin NC8 against the most sensitive bacterial strain, Micrococcus luteus CGMCC 1.193. The results showed that plantaricin NC8 induced membrane permeabilization and caused cell membrane disruption to M. luteus CGMCC 1.193 cells, as evidenced by electrolyte efflux, loss of proton motive force, and ATP depletion within a few minutes of plantaricin NC8 treatment. Furthermore, scanning and transmission electron microscopy showed that plantaricin NC8 had a drastic impact on the structure and integrity of M. luteus CGMCC 1.193 cells. In addition, we found that either PLNC8α or PLNC8β alone exhibited membrane permeabilization activity, but that PLNC8β had higher permeabilization activity, and their individual effects were not as strong as that of the combined compounds as plantaricin NC8. Finally, we showed that lipid II is not the specific target of plantaricin NC8 against M. luteus CGMCC 1.193. Our study reveals the antimicrobial mechanism of plantaricin NC8 against M. luteus CGMCC 1.193.

We experimentally demonstrate an optical MIMO NOMA-VLC system, which offers a high throughput and system capacity. The effect of the inter-user interference with high-order modulation is investigated. MIMO NOMA-VLC with 6 users is demonstrated.

International audience; In this paper, we propose a theoretical model for the intensity of a blurred image of a light source (LS) due to defocusing in optical camera communications. The blurred image is characterized with four parameters of half power full width, maximum intensity, left and right slope of hazy area and we relate them to the LS, channel, and camera settings. We experimentally investigate the impact of these parameters on characterization of the blurred image and compare it with the predicted data. The results show that if the size of the LS compared to its distance from the camera is less than a certain value set by the camera settings, the interference level between two close LSs increases, i.e. by increasing the link span, the size of the image increases.

Gradient doping ensures uniform transverse gain in an edge-pumped multislab pulsed amplifier, and a 1D iterative method is developed to generate the proper doping profile. Our investigations show that uniform gain under short pump duration tp = 0.25 ms can be readily achieved, where the modulation of the gain distribution is lower than 1.05 even if the diagonal transverse gain-length product (DTGLP) increases up to 5. For tp = 1.0 ms, comparable modulation of the gain distribution is achieved for a much lower DTGLP value of 2.3. To extend the DTGLP range for long pump duration, a modified 1D iterative method with an effectively “shortened” lifetime of the active ions is developed. With the modified method, the gain uniformity for both pumping conditions is greatly improved, and specifically, the DTGLP increases from 2.3 to 3.0 for tp = 1.0 ms. In addition, degradation of the gain uniformity resulting from deviations of the doping concentration is discussed. The deviations should be at least lower than 1% and 5% for tp = 1.0 ms and tp = 0.25 ms to maintain the gain uniformity, respectively. Our investigations might provide a useful way to design the amplifier with uniform gain in the beam aperture of a high average power pulsed laser.Gradient doping ensures uniform transverse gain in an edge-pumped multislab pulsed amplifier, and a 1D iterative method is developed to generate the proper doping profile. Our investigations show that uniform gain under short pump duration tp = 0.25 ms can be readily achieved, where the modulation of the gain distribution is lower than 1.05 even if the diagonal transverse gain-length product (DTGLP) increases up to 5. For tp = 1.0 ms, comparable modulation of the gain distribution is achieved for a much lower DTGLP value of 2.3. To extend the DTGLP range for long pump duration, a modified 1D iterative method with an effectively “shortened” lifetime of the active ions is developed. With the modified method, the gain uniformity for both pumping conditions is greatly improved, and specifically, the DTGLP increases from 2.3 to 3.0 for tp = 1.0 ms. In addition, degradation of the gain uniformity resulting from deviations of the doping concentration is discussed. The deviations should be at least lower than 1% ...

Deep energy fields in the Tahe Oilfield are studied and the relationship between energy fields and hydrocarbon migration and accumulation is discussed through the comprehensive analyses of energy field characteristics. Multi-phase tectonic stresses are the main controlling factor of the developmental morphologies of the present fractures. The characteristics of the present regional tectonic stress indicate that the Tahe Oilfield is a favorable area for hydrocarbon collection. The present pressure field of the Ordovician is a slightly low abnormal pressure system. The fluid potential characteristics show that there are two hydrocarbon migration trends: one is from east to west in part of the eastern area, and the other is from south to north in the whole southern area. The present formation water is of typical CaCl2 type. According to the formation water geochemistry, the Tahe Oilfield has a good seal capability, favorable for hydrocarbon accumulation and preservation. Aqueous inclusions indicate that homogenization temperatures are mainly 80–100°C, 120–130°C, and 150–170°C, therein, 80–100°C and 120–130°C represent two large scale hydrocarbon accumulation phases, Early Hercynian and Himalayan, and 150–170°C is controlled by tectonic event and Permian magmatic activities, representing a partial hydrocarbon accumulation event. 摘 要: 以塔河油田深层能量场为研究对象，通过系统分析能量场特征来探讨其与油气运聚的关系。研究认为，多期构造应力作用是塔河油田现今断裂发育形态的主控因素，现今区域应力场特征表明塔河油田是油气运移的有利指向区；奥陶系现今压力场整体上属于略偏低异常的压力系统，流体势特征显示油气运移存在东部自东向西局部性运移趋势以及南部由南向北区域性运移趋势；奥陶系现今地层水离子构成符合典型的CaCl2型水特征，地层水地化指标显示塔河主油区具有良好的封闭性，是油气聚集保存的有利区；盐水包裹体均一温度测试结果主要集中在80～100 ℃、120～130 ℃和150～170 ℃等3个温度段，前两个温度段分别对应于塔河油田2次大规模的油气成藏期：海西早期和喜马拉雅期，而最后一个温度段主要受控于构造变动和二叠系岩浆活动，代表了一期局部油气成藏事件。图7参22 Key words: Tahe Oilfield, deep carbonates, energy field, hydrocarbon migration, hydrocarbon accumulation

Two kinds of margin respectively occur in the Ordos Basin during the Middle-Late Triassic (Yanchang Age), one is foreland margin developed under the background of flexural subsidence by thrusting intensively in the southwest margin, and the other is intracratonic basin margin by stable subsidence in northern and central parts of the basin. The Middle-Late Triassic Yanchang Formation can be divided into four regional third-order sequences, which are separated by gentle angular unconformity or regional erosion surface, made up of lowstand system tract (LST), expanding system tract (EST) and highstand system tract (HST) from lower to upper within a sequence. But there are distinct differences of the sequence framework between the southwest margin and northern and central parts of the basin. The southwest margin develops heavy conglomerate layer and unconformity as a result of orogeny by thrusting, and the intracratonic basin margin by stable subsidence in the northern and central parts grows aggradational sandstone, conglomerate in fluvio-delta system and parallel unconformity. The depositional framework of southwest margin reflects the tectonic evolution from flexural subsidence by thrusting to rebounded uplift. The formation of sequence boundary is related to the resilient uplift and erosion. The sequence stratigraphic framework and depositional system tract configuration in the foreland basin are controlled by structural activity of the fold and thrust belt, and the sequence succession reflects episodic thrusting of the Middle-Late Triassic toward the foreland basin. The sequence evolution in northern and central parts reflects the depositional succession of fluvio-delta system under intracratonic background, composed of coarse-grained sediment in braided channel deposit at the lower, meandering channel deposit in the middle and fine-grained sediment in the flood plain at the upper, dominated by lake level fluctuation. During the deposit of the LST in the intracraton basin, accommodation space is limited, and results in abundant fluvial sediment migration laterally, erosion and transport, forming laterally sandstone composite and aggradational deposit on the alluvial plain, which constitutes specific erosion unconformity boundary.

Many achievements have been made in experimental studies of hydrocarbon migration in the clastic reservoir. On the other hand, few migration experiments have been reported in the carbonate reservoir simulation realm. This article is a tentative experimental study on hydrocarbon migration and accumulation in the carbonate reservoir, which is a complex media that includes a pore system and fracture system. This microcosmic experiment simulates oil-water displacement using a real core model. Plentiful seepage phenomena were observed in the microcosmic experiments. Three kinds of pathways were found in the plane: parallel pathway, oblique-cross pathway and network pathway. Three types of flow were found: continuous flow, sectioning flow and their combination. Three driving fronts were found in the experiment: piston front, encircle front and impulse front. All these vary with many factors such as fluid pressure, oil saturation, fissure configuration and wettability, and these factors affect each other. The results show that the relation between the fluid pressure and volume of flow is a complex segmenting correlation, instead of a simple positive correlation like the pipe flow that follows Darcy’s law. The relation between fluid pressure and the speed of flow also follows the same correlation. Speed of flow relates to the angle and width of the fissure. Speed of flow in the wide fissure that has an acute angle with the pressure gradient is faster than that in a narrow fissure with a high angle with the pressure gradient.

This paper introduces a high precision automated test system. We built an automated testing platform using programmable test equipments and designed a series of test boards to adapt the test process. Combined virtual instrument technology and software radio technology, we realized to test the wireless sensor network IC automatically. Compared with other test system, this system has the advantages of high precision, high degree of automation and strong portability etc. It's fast and convenient to change test function and has a lowest cost of long-term use. This system can be used in the laboratory test and small batch automated test system, and also can be applied to large quantities of chip test production line.

The effect of refiners containing Ti, B elements on the microstructure of purity aluminum has been studied in detail with optical microscopy, scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDAX). It is shown that salts mixture containing 5Ti1B is the best refiner with the finest α-Al grain and more than 10 h fading time. It is ascertained from the analysis of SEM–EDAX and thermodynamics analysis that the refining mechanism of salts mixture is mainly contributed to the heterogeneous nuclei of more fine TiAl3 particles dispersed in the melting, which come from the reaction between the salts and aluminum. While (Al,Ti)B2 has little or no refining effect, but it will reduce the size of TiAl3 since the TiAl3 nucleates and grows along the (Al,Ti)B2 particle. That is to say, B atom has also refining effect on the purity aluminum when it is added simultaneously with Ti atom.

Two-dimensional photonic crystal slab waveguides on SOI wafer are designed and fabricated. Photonic band gap, band gap guided mode, and index guided mode are observed by measuring the transmission spectra. The experimental results are in good agreement with the theoretical ones.

International audience