bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution and Antigenicity of Fibronectin Binding Proteins (SfbI and SfbII) of
Streptococcus pyogenes
Clinical Isolates from the Northern Territory, Australia
Authors: Goodfellow Alison M. , Hibble Megan , Talay Susanne R. , Kreikemeyer Bernd , Currie Bart J. , Sriprakash Kadaba S. , Chhatwal Gursharan S.
Published: May 2021

Fibronectin binding proteins play an important role in the adherence and invasion of group A streptococci (GAS). Genotypically distinct GAS isolates were screened for the presence and expression of two streptococcal fibronectin binding protein genes,
sfbI
and
sfbII
. Of the tested strains, 64 and 36% were shown to harbor and express the
sfbI
and
sfbII
genes, respectively. All
sfbII
-positive strains tested were also positive for
sfbI
, but only 28% of the
sfbII
-negative strains were positive for
sfbI
. High levels of immunoglobulin G antibodies to both SfbI and SfbII were found in sera from 80 subjects with defined streptococcal infections.
Microascus cinereus
(Anamorph
Scopulariopsis
) Brain Abscess in a Bone Marrow Transplant Recipient
Authors: Baddley John W. , Moser Stephen A. , Sutton Deanna A. , Pappas Peter G.
Published: May 2021

We report the first documented case of brain abscess due to the dematiaceous fungus
Microascus cinereus
, an organism common in soil and stored grain.
M. cinereus
was isolated from brain abscess material from a bone marrow transplant recipient. The patient responded well to treatment by amphotericin B lipid complex, itraconazole, and a craniotomy but later died from secondary complications caused by graft-versus-host disease.
Mink Lung Cells and Mixed Mink Lung and A549 Cells for Rapid Detection of Influenza Virus and Other Respiratory Viruses
Authors: Huang Yung T. , Turchek Brian M.
Published: May 2021

Mink lung cells were more sensitive than the commonly used MDCK or pRhMK cells for rapid detection of influenza virus A from clinical specimens. Mixed Mv1Lu and A549 cells in a single shell vial were synergistic for detection of influenza virus A and were as sensitive as individual cells for detection of other respiratory viruses.
Pulsed-Field Gel Electrophoresis-Based Molecular Comparison of
Vibrio cholerae
O1 Isolates from Domestic and Imported Cases of Cholera in Japan
Authors: Arakawa Eiji , Murase Toshiyuki , Matsushita Shigeru , Shimada Toshio , Yamai Shiro , Ito Takeshi , Watanabe Haruo
Published: May 2021

Sixty-seven
Vibrio cholerae
O1 El Tor isolates (36 domestic and 31 imported) were classified into 19 subtypes by
Not
I- and
Sfi
I-digested pulsed-field gel electrophoresis. Twenty-five of 36 domestic and 4 imported isolates were assigned to a
Not
I-A1–
Sfi
I-A1 subtype, suggesting that this pulse type is widely distributed in Asia and Japan.
Aspergillus fumigatus
Antigen Detection in Sera from Patients at Risk for Invasive Aspergillosis
Authors: Chumpitazi Bernabé F. F. , Pinel Claudine , Lebeau Bernadette , Ambroise-Thomas Pierre , Grillot Renee
Published: May 2021

We have developed an inhibition enzyme immunoassay (inhibition-EIA) to monitor for the occurrence of invasive aspergillosis (IA) in sera from 45 immunocompromised (IC) patients. The test uses rabbit polyclonal antibodies and a mixture of components from
Aspergillus fumigatus
, containing three predominant antigens with molecular weights of 18,000, 33,000, and 56,000. Circulating antigens were found in five of seven proven cases of IA due to
A. fumigatus
. In two of the five positive cases, antigenemia was detected with inhibition-EIA earlier than with X ray or other biological methods. No antigens were detected in the sera from two patients with proven IA due to
Aspergillus flavus
and
Aspergillus terreus
nor in the sera from four patients with probable IA. Circulating antigens were not detected in the control group, composed of 30 healthy adult blood donors. Four of the 32 at-risk patients examined, though they displayed no definite evidence of IA, gave a positive result in this test. The sensitivity, specificity, and positive predictive value of inhibition-EIA were 71.4, 94.4, and 71.2%, respectively. The data were compared with those obtained by a latex agglutination assay of galactomannan (GM) that was positive in only one patient with probable IA. The higher sensitivity obtained by inhibition-EIA may well be due to its ability to detect circulating antigens other than GM in the sera of IC patients with IA. Detecting these antigens may improve the diagnosis of IA, as they may serve as markers of this infection.
Natural Infection of Domestic Goats withEhrlichia chaffeensis
Authors: Dugan Vivien G. , Little Susan E. , Stallknecht David E. , Beall Ashley D.
Published: May 2021

Thirty-eight domestic goats from an area ofEhrlichia chaffeensisendemicity were tested for antibodies reactive toE. chaffeensisand forE. chaffeensis-specific 16S rRNA gene fragments by an indirect fluorescent antibody test and a nested PCR assay, respectively. Twenty-eight of 38 (73.7%) goats had antibodies reactive toE. chaffeensis(≥1:128), and 6 of 38 (15.8%) goats were positive by diagnostic PCR;E. chaffeensiswas isolated in cell culture from one goat. Our data indicate that goats in areas of endemicity are naturally exposed to and infected withE. chaffeensis.
A Clonal Subpopulation of
Leptospira interrogans
Sensu Stricto Is the Major Cause of Leptospirosis Outbreaks in Brazil
Authors: Pereira M. M. , Matsuo M. G. S. , Bauab A. R. , Vasconcelos S. A. , Moraes Z. M. , Baranton G. , Saint Girons I.
Published: May 2021

Leptospira
is a highly diverse genus comprising many species and serogroups in Brazil as well as all over the world. However, a study by arbitrarily primed PCR of 44 leptospiral strains isolated from humans during three different outbreaks in Brazilian urban centers reveals that 43 of 44 isolates exhibit very similar fingerprints. Analysis of these isolates indicates that they belong to a clonal subpopulation of
Leptospira interrogans
sensu stricto.
Peritonitis Due to
Roseomonas fauriae
in a Patient Undergoing Continuous Ambulatory Peritoneal Dialysis
Authors: Bibashi Evangelia , Sofianou Danai , Kontopoulou Konstantina , Mitsopoulos Efstathios , Kokolina Elisabeth
Published: May 2021

Roseomonas
is a newly described genus of pink-pigmented, nonfermentative, gram-negative bacteria that have been recognized as a cause of human infections.
Roseomonas fauriae
is a species rarely isolated from clinical specimens. We report the first known case of peritonitis caused by
R. fauriae
in a patient receiving continuous ambulatory peritoneal dialysis.
Isolation of
Pantoea agglomerans
in Two Cases of Septic Monoarthritis after Plant Thorn and Wood Sliver Injuries
Authors: De Champs C. , Le Seaux S. , Dubost J. J. , Boisgard S. , Sauvezie B. , Sirot J.
Published: May 2021

Arthritis after plant injury is often apparently aseptic. We report two cases due to
Pantoea agglomerans
. In one case, the bacterium was isolated only from the pediatric blood culture media, BACTEC Peds Plus, monitored in BACTEC 9240, and not from the other media inoculated with the joint fluid. This procedure could help improve the diagnosis of septic arthritis.
Streptococcus bovis
Meningitis in an Infant
Authors: Grant Russell J. , Whitehead Terence R. , Orr James E.
Published: May 2021

Streptococcus bovis
is a nonenterococcal, group D streptococcus which has been identified as a causative agent for serious human infections, including endocarditis, bacteremia, and septic arthritis. Several cases of adult
S. bovis
meningitis have been reported, usually in association with underlying disease. In the neonatal period, it is an uncommon agent of meningitis. We report, to our knowledge, the third documented case of neonatal
S. bovis
meningitis in the English language literature. As in the previous cases, this neonate showed no anatomical or congenital immunologic lesion which might be expected to predispose the patient to meningitis. Sequencing of the 16S ribosomal DNA gene was performed and a new PCR test was used to secure a more reliable identification of the strain.
Neutralization Assay for Human Group C Rotaviruses Using a Reverse Passive Hemagglutination Test for Endpoint Determination
Authors: Fujii Ritsushi , Kuzuya Mitsutaka , Hamano Masako , Ogura Hajime , Yamada Masao , Mori Tadashige
Published: May 2021

A novel neutralization assay for human group C rotavirus (CHRV) was developed by using a reverse passive hemagglutination (RPHA) test for endpoint determination. In this assay, the neutralization (N)-RPHA test, serial twofold dilutions of sera were mixed with a solution of CHRV that yielded an RPHA test titer of 8 at 3 days after infection. The mixtures were incubated at 37°C for 1 h and were inoculated onto CaCo-2 cell monolayers in a 96-well microplate. Maintenance medium containing 100 μg of pancreatin per ml was placed in each well. The plate was sealed with sticky plastic film and was incubated at 37°C for 3 days under continuous rotation. Then, the RPHA test titer of each well was determined. The neutralization titer was expressed as the reciprocal of the maximum dilution of the serum that exhibited a fourfold (75%) or greater reduction in the RPHA test titer (8 to 2 or less). Seroconversion of neutralizing antibody was demonstrated by this method in four sets of paired serum specimens from patients with diarrheal disease caused by CHRV. The seroprevalence of CHRV in the general population in Okayama Prefecture was 26.8% by immunofluorescence and 25.5% by the N-RPHA test. The N-RPHA test described here is the first system used to assay for a neutralization antibody against CHRV and is applicable in both clinical and epidemiological settings.
New Monoclonal Antibody Specific for
Candida albicans
Germ Tube
Authors: Marot-Leblond Agnes , Grimaud Linda , Nail Sandrine , Bouterige Sandrine , Apaire-Marchais Veronique , Sullivan Derek J. , Robert Raymond
Published: May 2021

Hydrophobic components of the germ tube of the dimorphic pathogenic fungus
Candida albicans
were used as immunogens to prepare monoclonal antibodies (MAbs). Among the resulting MAbs, one (MAb 16B1-F10) was shown by indirect immunofluorescence to be specific to the surface of the mycelium phase of the
C. albicans
and
C. stellatoidea
species. No labeling of any other genera and
Candida
species tested was observed, including
C. dubliniensis
, a newly described species which has many phenotypic similarities to
C. albicans
. This phase-specific epitope resides on a protein moiety. The molecular mass of the antigen released by Zymolyase digestion was determined by gel filtration and ranges from 25 to 166 kDa. The antigen was also shown to be highly hydrophobic. This anti-
C. albicans
cell wall surface-specific MAb may be a good candidate for use in tests for the rapid differentiation of the two closely related species
C. albicans
and
C. dubliniensis
.
Development and Evaluation of an Electronic Guide for Introductory Microbiology Skills
Authors: WRIGHT ALICE , HARDING ETHELYNDA E.
Published: May 2021

To increase the quality of instruction, enhance student learning, and decrease laboratory time spent on laboratory safety, basic skills, and the use of equipment, we developed the Micro eGuide website. We compared the performance of students who used the Micro eGuide to students provided more traditional instruction in both an upper-level introductory microbiology course for biology majors and in a lower-division introductory microbiology course for nonmajors. Assessment of student learning included written pretests and posttests, practical testing of laboratory skills, and for the major’s class, a review of poster presentations of independent projects. Students who used the Micro eGuide showed a statistically significant increase in performance on written examination in the introductory microbiology courses for both biology majors and nonmajors. Use of the Micro eGuide in the sophomore-level course for nonbiology majors resulted in a statistically significant improvement in laboratory skills. Though the increase in laboratory skills in the majors courses was not statistically significant, instructors were able to use the site as an effective learning source and decrease the time spent in class on topics covered in the Micro eGuide. While the number of student independent research projects was too small for statistical analysis on the quality of the poster presentations, the improvement in student attitude and the increase in the diversity in topics selected suggests that students using the Micro eGuide had increased comfort with microbiology and increased interest in exploring microbiology.
Alternative Assessment Strategy and Its Impact on Student Comprehension in an Undergraduate Microbiology Course
Authors: MARGULIES BARRY J. , GHENT CYNTHIA A.
Published: May 2021

Medical Microbiology is a content-intensive course that requires a large time commitment from the students. Students are typically biology or prenursing majors, including students headed for professional schools, such as medical school and pharmacy school. This group is somewhat diverse in terms of background science coursework, so it can be difficult to teach in a way that benefits all the students. Numerous changes have been implemented in our microbiology curriculum to address the different abilities of our students by altering assessment and teaching strategies. It was hypothesized that changing the assessment strategy from the traditional scheme of two or three exams and one final to a new model of seven or eight shorter exams would have a positive impact on student comprehension and retention. The quantity of material taught or expected of the students to learn did not change, but there was definitely an impact on them. Although 30.0% of students routinely did not pass microbiology in previous semesters, the new method of assessment resulted in only 9.63% not completing the semester successfully, as determined by earning a grade of C or better. There is some evidence from conversations and interviews with students that indicates a positive impact of this methodology on student attitude. Implementation of these changes in other courses and their current effectiveness will be examined in the future, with an eye towards more broadly applicable successful teaching techniques in the sciences, especially for nonmajors.
A “Hybrid” Bacteriology Course: The Professor’s Design and Expectations; The Students’ Performance and Assessment
Authors: KRAWIEC STEVEN , SALTER DIANE , KAY EDWIN J.
Published: May 2021

A basic bacteriology course was offered in two successive academic years, first in a conventional format and subsequently as a “hybrid” course. The latter combined (i) online presentation of content, (ii) an emphasis on online resources, (iii) thrice-weekly, face-to-face conversations to advance understanding, and (iv) frequent student postings on an electronic discussion board. We compared the two courses through statistical analysis of student performances on the final examinations and the course overall and student assessment of teaching. The data indicated that there was no statistical difference in performance on the final examinations or the course overall. Responses on an instrument of evaluation revealed that students less strongly affirmed the following measures in the hybrid course: (i) The amount of work was appropriate for the credit received, (ii) Interactions between students and instructor were positive, (iii) I learned a great deal in this course, and (iv) I would recommend this course to other students. We recommend clear direction about active learning tasks and relevant feedback to enhance learning in a hybrid course.
Revealing microstructural properties of shocked and tectonically deformed zircon from the Vredefort impact structure: Raman spectroscopy combined with SEM microanalyses
Authors: Kovaleva Elizaveta , Zamyatin Dmitry A.
Published: May 2021

Finite deformation patterns of accessory phases can indicate the tectonic regime and deformation history of the host rocks and geological units. In this study, tectonically deformed, seismically deformed, and shocked zircon grains from a granite sample from the core of the Vredefort impact structure were analyzed in situ, using a combination of Raman spectroscopy, backscatter electron (BSE) imaging, electron backscattered diffraction (EBSD) mapping, electron probe microanalyses (EPMA), energy-dispersive X-ray spectroscopy (EDS) qualitative chemical mapping, and cathodoluminescence (CL) imaging. We aimed to reveal the effects of marginal grain-size reduction, planar deformation bands (PDBs), and shock microtwins on the crystal structure and microchemistry of zircon.

Deformation patterns such as PDBs, microtwins, and subgrains did not show any significant effect on zircon crystallinity/metamictization degree or on the CL signature. However, the ratio of Raman band intensities B1g (1008 cm–1) to Eg (356 cm–1) slightly decreased within domains with low misorientation. The ratio values were affected in shocked grains, particularly in twinned domains with high misorientation. B1g/Eg ratio mapping combined with metamictization degree mapping (full width at half maximum of B1g peak) suggest the presence of shock deformation features in zircon; however, due to the lower spatial resolution of the method, they must be used in combination with the EBSD technique. Additionally, we discovered anatase, quartz, goethite, calcite, and hematite micro-inclusions in the studied zircon grains, with quartz and anatase specifically being associated with strongly deformed domains of shocked zircon crystals.
Shock deformation microstructures in xenotime from the Spider impact structure, Western Australia
Authors: Cox* Morgan A. , Cavosie Aaron J. , Poelchau Michael , Kenkmann Thomas , Bland Phil A. , Miljković Katarina
Published: May 2021

The rare earth element–bearing phosphate xenotime (YPO4) is isostructural with zircon, and therefore it has been predicted that xenotime forms similar shock deformation microstructures. However, systematic characterization of the range of microstructures that form in xenotime has not been conducted previously. Here, we report a study of 25 xenotime grains from 10 shatter cones in silicified sandstone from the Spider impact structure in Western Australia. We used electron backscatter diffraction (EBSD) in order to characterize deformation and microstructures within xenotime. The studied grains preserve multiple sets of planar fractures, lamellar {112} deformation twins, high-angle planar deformation bands (PDBs), partially recrystallized domains, and pre-impact polycrystalline grains. Pressure estimates from microstructures in coexisting minerals (quartz and zircon) allow some broad empirical constraints on formation conditions of ~10–20 GPa to be placed on the observed microstructures in xenotime; at present, more precise formation conditions are unavailable due to the absence of experimental constraints. Results from this study indicate that the most promising microstructures in xenotime for recording shock deformation are lamellar {112} twins, polycrystalline grains, and high-angle PDBs. The {112} deformation twins in xenotime are likely to be a diagnostic shock indicator, but they may require a different stress regime than that of {112} twinning in zircon. Likewise, polycrystalline grains are suggestive of impact-induced thermal recrystallization; however, in contrast to zircon, the impact-generated polycrystalline xenotime grains here appear to have formed in the solid state, and, in some cases, they may be difficult to distinguish from diagenetic xenotime with broadly similar textures.
Maxwell quasinormal modes on a global monopole Schwarzschild-anti-de Sitter black hole with Robin boundary conditions
Authors: Wang Mengjie , Chen Zhou , Pan Qiyuan , Jing Jiliang
Published: May 2021

We generalize our previous studies on the Maxwell quasinormal modes around Schwarzschild-anti-de-Sitter black holes with Robin type vanishing energy flux boundary conditions, by adding aglobal monopoleon the background. We first formulate the Maxwell equations both in the Regge–Wheeler–Zerilli and in the Teukolsky formalisms and derive, based on the vanishing energy flux principle,twoboundary conditions in each formalism. The Maxwell equations are then solved analytically in pure anti-de Sitter spacetimes with a global monopole, and twodifferentnormal modes are obtained due to the existence of the monopole parameter. In the small black hole and low frequency approximations, the Maxwell quasinormal modes are solved perturbatively on top of normal modes by using an asymptotic matching method, while beyond the aforementioned approximation, the Maxwell quasinormal modes are obtained numerically. We analyze the Maxwell quasinormal spectrum by varying the angular momentum quantum number$$\ell $$ℓ, the overtone numberN, and in particular, the monopole parameter$$8\pi \eta ^2$$8πη2. We show explicitly, through calculating quasinormal frequencies with both boundary conditions, that the global monopole produces the repulsive force.
General method for including Stueckelberg fields
Authors: Lyakhovich S. L.
Published: May 2021

A systematic procedure is proposed for inclusion of Stueckelberg fields. The procedure begins with the involutive closure when the original Lagrangian equations are complemented by all the lower order consequences. The Stueckelberg field is introduced for every consequence included into the closure. The generators of the Stueckelberg gauge symmetry begin with the operators generating the closure of original system. These operators are not assumed to be a generators of gauge symmetry of any part of the original action, nor are they supposed to form an on shell integrable distribution. With the most general closure generators, the consistent gauge invariant theory is iteratively constructed, without obstructions at any stage. The Batalin–Vilkovisky form of inclusion of the Stueckelberg fields is worked out and the existence theorem for the Stueckelberg action is proven.
Effects of Stimulating Local and Distal Acupoints on Diabetic Gastroparesis: A New Insight in Revealing Acupuncture Therapeutics
Authors: Yu Bo , Sun Mengmeng , Wang Zhihong , Zhu Bing , Xue Jingquan , Yang Wenjiang , Gao Xinyan , Zhi Mujun , Cao Jiazhen , Zhao Jinying , Zhao Xuewei , Liu Wu , Wang Fuchun , Li Tie
Published: May 2021

One of the most important aspects of clinical acupuncture practice, like diabetic gastroparesis, is the selection of suitable acupoints. Furthermore, it is critical to examine the therapeutic impact differences between distal and local acupoints, as well as the prescription of their combination. In this study, diabetic gastroparesis rats were treated by needling Zhongwan (CV12) and Zusanli (ST36), and then used Single Photon Emission Computed Tomography-CT (SPECT-CT) technology to assess the effects of promoting gastric motility. In addition, morphological observation, immunohistochemical examination, and biomarker assays, such as determination of growth factor 1, motilin, and ghrelin contents in serum samples, were performed to better understand the impact of certain various acupuncture treatments. All of the therapies improved the symptoms of diabetic gastroparesis rats, according to the findings. Stimulating these acupoints, on the other hand, can have a different therapeutic effect. In addition, needling local and distal acupoints together can have an antagonistic or synergistic impact on specific physiological and biochemical indexes such as gastric motility, ghrelin, gastrin, and growth factor 1, among others. Our findings demonstrated the benefits of acupoints and acupuncture in the management of diabetic gastroparesis, as well as a new insight into acupuncture therapeutics.
Apigenin Alleviates Oxidative Stress-Induced Cellular Senescence via Modulation of the SIRT1-NAD+-CD38 Axis
Authors: Li Bing Si , Zhu Ri Zhe , Lim Seok-Hee , Seo Jae Ho , Choi Byung-Min
Published: May 2021

Oxidative stress-induced cellular senescence is now regarded as an important driving mechanism in chronic lung diseases-particularly chronic obstructive pulmonary disease (COPD). 4[Formula: see text],5,7-trihydroxyflavone (Apigenin) is a natural flavonoid product abundantly present in fruits, vegetables, and Chinese medicinal herbs. It has been known that apigenin has anti-oxidant, anti-inflammatory and liver-protecting effects. The efficacy of apigenin for lung aging, however, has not been reported. In this study, we selected the hydrogen peroxide (H2O[Formula: see text]- or doxorubicin (DOXO)-induced senescence model in WI-38 human embryonic lung fibroblast cells to determine the potential anti-aging effects of apigenin in vitro and associated molecular mechanisms. We found that apigenin reduced senescence-associated [Formula: see text]-galactosidase (SA-[Formula: see text]-gal) activity and promoted cell growth, concomitant with a decrease in levels of Acetyl (ac)-p53, p21[Formula: see text], and p16[Formula: see text] and an increase in phospho (p)-Rb. Apigenin also increased the activation ratio of silent information regulator 1 (SIRT1), nicotinamide adenine dinucleotide (NAD[Formula: see text], and NAD[Formula: see text]/NADH and inhibited cluster of differentiation 38 (CD38) activity in a concentration-dependent manner. SIRT1 inhibition by SIRT1 siRNA abolished the anti-aging effect of apigenin. In addition, CD38 inhibition by CD38 siRNA or apigenin increased the SIRT1 level and reduced H2O2-induced senescence. Our findings suggest that apigenin is a promising phytochemical for reducing the impact of senescent cells in age-related lung diseases such as COPD.
A Semi-Analytical Method for the 3D Elastic Structural-Acoustic Radiation in Shallow Water
Authors: Qian Zhiwen , Shang Dejiang , Xu Xinyang , He Yuanan , Zhai Jingsheng
Published: May 2021

A hybrid computational method is proposed for three-dimensional structural-acoustic radiation in shallow water, which combines the wave superposition method (WSM) with the adjustable Green function and the multi-physical-coupled finite element method (FEM). A low-frequency acoustic model in the near field is established by the FEM to discretize the continuous and arbitrary-shaped radiator, and the normal vibration velocity on the wetted surface is used as the input in the WSM to calculate the strengths of simple sources enclosed within the radiator. Finally, the sound propagation in the far field of the elastic structure is efficiently computed by superimposing the sound field of each simple source. The numerical examples of the pulsating sphere and elastic spherical shell in the shallow water are developed to verify the high accuracy and efficiency of the presented method, respectively. Moreover, the regularization algorithms are employed as the complementary approaches to improve the stability of this method in engineering practices, it is found that the algorithms can significantly hold the calculation accuracy in case the velocity data contain noise, and the least-squares QR is an efficient and accurate method with a few iteration numbers and better stability effect as compared with other algorithms.
A Method of Amino Acid Terahertz Spectrum Recognition Based on the Convolutional Neural Network and Bidirectional Gated Recurrent Network Model
Authors: Li Tao , Xu Yuanyuan , Luo Jiliang , He Jianan , Lin Shiming
Published: May 2021

In order to improve the accuracy of amino acid identification, a model based on the convolutional neural network (CNN) and bidirectional gated recurrent network (BiGRU) is proposed for terahertz spectrum identification of amino acids. First, we use the CNN to extract the feature information of the terahertz spectrum; then, we use the BiGRU to process the feature vector of the amino acid time-domain spectrum, describe the time series dynamic change information, and finally achieve amino acid identification through the fully connected network. Experiments are carried out on the terahertz spectra of various amino acids. The experimental results show that the CNN-BiGRU model proposed in this study can effectively realize the terahertz spectrum identification of amino acids and will provide a new and effective analysis method for the identification of amino acids by terahertz spectroscopy technology.
Fine-Grained and Controllably Redactable Blockchain with Harmful Data Forced Removal
Authors: Hou Huiying , Hao Shidi , Yuan Jiaming , Xu Shengmin , Zhao Yunlei
Published: May 2021

Notoriously, immutability is one of the most striking properties of blockchains. As the data contained in blockchains may be compelled to redact for personal and legal reasons, immutability needs to be skillfully broken. In most existing redactable blockchains, fine-grained redaction and effective deletion of harmful data are mutually exclusive. To close the gap, we propose a fine-grained and controllably redactable blockchain with harmful data forced removal. In the scheme, the originator of the transaction has fine-grained control over who can perform the redaction and which portions of the transaction can be redacted. The redaction transaction is performed after collecting enough votes from miners. All users can provide the index of the block containing the harmful data to receive rewards, which are borne by the malicious user who initially posted the data. Miners can forcibly remove the harmful data based on the index. The malicious user will be blacklisted if the reward is not paid within a period of time, and any transaction about such user will not be performed later. In addition, the scheme supports the redaction of additional data and unexpended transaction output (UTXO) simultaneously. We demonstrate that the scheme is secure and feasible via formal security analysis and proof-of-concept implementation.
[Retracted] Monitoring System of Key Technical Features of Male Tennis Players Based on Internet of Things Security Technology
Authors: Wu Guodong
Published: May 2021

Nowadays, the development and innovation of tennis have basically been integrated with the Internet, and the penetration of big data is accelerating the development of tennis. Collect data and statistics about tennis matches, analyze the key winning factors of the game, assign players’ gains and losses, and assign points. Fully understand the game’s tactics and various key technical functions of the player and enhance the influence of the game’s attention. Therefore, as the era of the Internet of Things is about to come, the development of sports events in my country should seize the opportunity of innovation in the application of Internet of Things technology, accelerate the process of upgrading informatization and intelligence, and achieve leapfrog development. This article is aimed at studying the use of the Internet of Things security technology, research, and design a monitoring system for the key technical characteristics of male tennis players. This paper proposes to develop a novel real‐time video semantic analysis prototype system for tennis matches, taking the video from the monitoring perspective of tennis matches as the analysis object. The experimental results in this article show that from Wimbledon to the Australian Open, the Australian Open is very slow, and finally, to the French Open, the speed of the ball slows down and improves the accuracy of the tennis crisis system. The average level and the correct answer rate are 61.37%. Eventually, it rose from the highest 86.13% to 86.92%, and the highest was the lowest. It seems that a monitoring system for the basic technical characteristics of male tennis players is more feasible.
A Medical Image Classification Model Based on Adversarial Lesion Enhancement
Authors: Zhang Bing , Hu Xu
Published: May 2021

With the development of Artificial Intelligence, the auxiliary diagnosis model based on deep learning can assist doctors to a certain extent. However, the latent information in medical images, such as lesion features, is ignored in most of the traditional methods. The extraction of this information is regarded as a learning task within the network in some recent researches, but it requires a large amount of fine-labeled data, which is undoubtedly expensive. In response to the problem above, this paper proposes an Adversarial Lesion Enhancement Neural Network for Medical Image Classification (ALENN), which is used to locate and enhance the lesion information in medical images only under weakly annotated data so as to improve the accuracy of the auxiliary diagnosis model. This method is a two-stage framework, including a structure-based lesion adversarial inpainting module and a lesion enhancement classification module. The first stage is used to repair the lesion area in the images while the second stage is used to locate the lesion area and use the lesion enhanced data during modeling process. In the end, we verified the effectiveness of our method on the MURA dataset, a musculoskeletal X-ray dataset released by Stanford University. Experimental results show that our method can not only locate the lesion area but also improve the effectiveness of the auxiliary diagnosis model.
Degradation of High-Concentration Nitrate Nitrogen in Groundwater: A Laboratory Study
Authors: Liu Manxi , Xia Lu , Liu Ruinan , Gao Zongjun , Han Cong , Feng Jianguo , Wang Jing , Qu Wanlong , Xing Tongju
Published: May 2021

To investigate effective and reasonable methods for the remediation of nitrate nitrogen pollution in groundwater, two groups of laboratory denitrification experiments were conducted: one on the effect of native denitrifying microbes in groundwater and another on the effect of artificially added denitrifying microbes. The water used in the experiment was typical groundwater with a high concentration of nitrate nitrogen. The temperature was controlled at 15°C. Both groups of experiments established four types of culture environments: anaerobic, anaerobic with an added carbon source (glucose), aerobic, and aerobic with an added carbon source (glucose). The results indicated that native denitrifying microbes in the groundwater have almost no ability to remove high concentrations of nitrate nitrogen. However, artificially added denitrifying microbes can effectively promote denitrification. Artificially added denitrifying microbes had the highest activity in an anaerobic environment in which a carbon source had been added, and the rate removal of a high concentration of nitrate nitrogen in groundwater was the highest and reached as high as 89.52%.
Data‐Driven Fault Diagnosis for Rolling Bearing Based on DIT‐FFT and XGBoost
Authors: Xiang Chuan , Ren Zejun , Shi Pengfei , Zhao Hongge
Published: May 2021

The rolling bearing is an extremely important basic mechanical device. The diagnosis of its fault play an important role in the safe and stable operation of the mechanical system. This study proposed an approach, based on the Fast Fourier Transform (FFT) with Decimation‐In‐Time (DIT) and XGBoost algorithm, to identify the fault type of bearing quickly and accurately. Firstly, the original vibration signal of rolling bearing was transformed by DIT‐FFT and divided into the training set and test set. Next, the training set was used to train the fault diagnosis XGBoost model, and the test set was used to validate the well‐trained XGBoost model. Finally, the proposed approach was compared with some common methods. It is demonstrated that the proposed approach is able to diagnose and identify the fault type of bearing quickly with almost 99% accuracy. It is more accurate than Machine Learning (89.88%), Ensemble Learning (93.25%), and Deep Learning (95%). This approach is suitable for the fault diagnosis of rolling bearing.
Protective Effects of Hydroalcoholic Extract of Rosa canina Fruit on Vancomycin-Induced Nephrotoxicity in Rats
Authors: Sadeghi Hossein , Karimizadeh Ehsan , Sadeghi Heibatollah , Panahi kokhdan Esmaeel , Mansourian Mahboubeh , Abbaszadeh-Goudarzi Kazem , Shokripour Mansoureh , Asfaram Arash , Doustimotlagh Amir Hossein
Published: May 2021

Vancomycin-induced nephrotoxicity (VIN) has been reported to occur in 5–35% of recipient patients. The aims of the study were to evaluate protective effects of Rosa canina (RC) on VIN in rats. Rats were randomly divided into five groups as follows: control group I, group II (received VAN 400 mg/kg/day, every 12 h at doses of 200 mg/kg/day, for 7 consecutive days), group III (VAN + RC 250 mg/kg/day, for 7 consecutive days), group IV (VAN + RC 500 mg/kg/day, for consecutive days), and group V (received RC 500 mg/kg/day, for consecutive 7 days). On the eighth day after anesthetizing the animals, blood samples were taken from the heart, and then, the kidneys were removed to investigate kidney function, oxidative stress, and histopathological marker. Also, the chemical composition of RC extract was identified by GC-MS analysis. Oral dose of 500 mg/kg RC extract significantly reduced the serum levels of blood urea nitrogen (BUN), creatinine (Cr), malondialdehyde (MDA), and nitric oxide (NO) and also the kidney tissue MDA, protein carbonyl, and NO metabolites (nitrite) levels compared to the VAN-treated group (

P
<
0.05

). Based on histopathological analysis, RC extract at the dose of 500 mg/kg inhibited the destructive effects of VAN on kidney tissues. GC-MS analysis indicated that the main compositions were found to be lactose (21.96%), 3-t-butyloxaziridine (20.91%), and 5-oxymethylfurfurole (16.75%). The results indicated that oral administration of RC was able to reduce VAN-induced nephrotoxicity in rats, possibly through antioxidant pathways.
Association of Body Fat Percentage with Time in Range Generated by Continuous Glucose Monitoring during Continuous Subcutaneous Insulin Infusion Therapy in Type 2 Diabetes
Authors: Ruan Yuting , Zhong Jiana , Chen Rongping , Zhang Zhen , Liu Dixing , Sun Jia , Chen Hong
Published: May 2021

Background. Obesity is a crucial risk factor associated with type 2 diabetes mellitus (T2DM). Excessive accumulation of body fat may affect the glycemia control in T2DM. This study investigated the relationship between body fat percentage and time in range (TIR) assessed by continuous glucose monitoring (CGM) during short-term continuous subcutaneous insulin infusion (CSII) therapy in T2DM patients. Method. A total of 85 T2DM patients were recruited in this cross-sectional study. All participants underwent 72 h CGM period during short-term CSII therapy. TIR was defined as the percentage of time spent within the target glucose range of 3.9-10.0 mmol/L. Body composition was measured using bioelectrical impedance analysis (BIA) and overfat was defined as an amount of body fat of at least 25% of total body mass for men or at least 30% for women. Multiple linear regression models were used to evaluate the independent association of body fat percentage with TIR after adjusting for confounding factors. Results. Compared with normal fat T2DM patients, individual with a higher body fat percentage exhibited lower levels of TIR (

P
=
0.004

) and higher 72 h mean blood glucose (72 h MBG) (

P
=
0.001

) during short-term CSII treatment. The prevalence of overfat assessed by body fat percentage decreased with the ascending TIR tertiles (

P
<
0.05

). Multiple linear regression analysis indicated that body fat percentage was significantly associated with TIR independent of age, gender, diabetes duration, HbA1c, and BMI (

P
=
0.043

). Conclusions. Body fat percentage was significantly associated with TIR in T2DM during short-term CSII therapy. Reduction of body fat may be an important therapeutic target to improve glycemic control in high body fat T2DM patients, who may benefit less from intensive insulin treatment.
Enhanced Thermal Insulation and Flame-Retardant Properties of Polyvinyl Alcohol-Based Aerogels Composited with Ammonium Polyphosphate and Chitosan
Authors: Luo MinYi , Xu Jiayou , Lv Shu , Yuan XueFeng , Liang Xiaolan
Published: May 2021

Polyvinyl alcohol- (PVA-) based aerogels have attracted widespread attention owing to their low cost, eco-friendliness, and low density. However, the applications of PVA-based aerogels are limited by their flammability. In this study, a flame retardant, ammonium polyphosphate (APP), and a biopolymer, chitosan (CS), were added to polyvinyl alcohol (PVA), and the polymer was further crosslinked using boric acid (H3BO3). In the PVA aerogels, the negatively charged APP and positively charged CS formed a polyelectrolyte complex (PEC) through ionic interaction. Cone calorimetry and vertical burning tests (UL-94) indicated that the PVA composite aerogels have excellent flame retardancy; they could decrease the heat release rate, total heat release rate, and carbon dioxide (CO2) generation. Both PVA/H3BO3 and APP-CS in the composite aerogel could be burned to carbon, and the foamed char layer could act together to impart the PVA composite aerogels with good flame retardancy. Further, the decrease in the temperature at the backside of the aerogels with increasing APP-CS content, as determined by the flame-spraying experiment, indicated that the PVA-based aerogels with APP-CS can also serve as thermal insulation materials. This work provides an effective and promising method for the preparation of PVA-based aerogels with good flame retardancy and thermal insulation property for construction materials.
Tag-Aware Recommender System Based on Deep Reinforcement Learning
Authors: Zhao Zhiruo , Chen Xiliang , Xu Zhixiong , Cao Lei
Published: May 2021

Recently, the application of deep reinforcement learning in the recommender system is flourishing and stands out by overcoming drawbacks of traditional methods and achieving high recommendation quality. The dynamics, long-term returns, and sparse data issues in the recommender system have been effectively solved. But the application of deep reinforcement learning brings problems of interpretability, overfitting, complex reward function design, and user cold start. This study proposed a tag-aware recommender system based on deep reinforcement learning without complex function design, taking advantage of tags to make up for the interpretability problems existing in the recommender system. Our experiment is carried out on the MovieLens dataset. The result shows that the DRL-based recommender system is superior than traditional algorithms in minimum error, and the application of tags have little effect on accuracy when making up for interpretability. In addition, the DRL-based recommender system has excellent performance on user cold start problems.
Preparation and Assessment of Some Characteristics of Nanoparticles Based on Sodium Alginate, Chitosan, and Camellia chrysantha Polyphenols
Authors: Luong Phu Hoang , Nguyen Thuy Chinh , Pham The Dan , Tran Do Mai Trang , Ly Thi Ngoc Lien , Vu Quoc Trung , Tran Thi Kim Ngan , Thai Hoang
Published: May 2021

This paper presents the characteristics, morphology, and properties of alginate/chitosan/polyphenol nanoparticles, in which polyphenols were extracted from Camellia chrysantha leaves collected in Tam Dao district, Vinh Phuc province (Vietnam). The alginate/chitosan/polyphenol nanoparticles were prepared by ionic gelation method at different polyphenol content. The characteristics and morphology of these nanoparticles were investigated using infrared spectroscopy (IR), ultraviolet-visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM). Release kinetic of polyphenols from the alginate/chitosan/polyphenol nanoparticles was conducted in simulated human body fluids. The release kinetics of polyphenols from the above nanoparticles were also evaluated and discussed. The experimental results showed that the release process of polyphenols from the nanoparticles was dependent on three factors: time, pH of solution, and amount of polyphenols.
Vibration Transmission Characteristics and Detection Method of Bilateral Chain Drive of Multicylinders
Authors: Li Yu , Tang Zhong , Zhang Ben , Wang Meilin
Published: May 2021

The transmission modes of multiple rotating parts on the combine harvester are complex and diverse, and the excitation vibrations are coupled with each other, which makes it difficult to dynamically balance the parallel rotating bodies on-site. In order to obtain the influence of the multicylinder transmission system on the vibration response and transmission characteristics of the whole machine providing an experimental basis for the overall balance of the multicylinder system, this paper tested and analyzed the vibration response and shaft vibration state of the system under different transmission modes. On this basis, the influence of chain drive and different transmission modes on the vibration characteristics of the multicylinder was analyzed. Through the tests of the vibration response of the multicylinder frame, the main transfer path of the vibration of each excitation source was analyzed. The results showed that the transmission chain and transmission mode would affect the stiffness, damping, and vibration response of the cylinder fundamental frequency of the chain transmission system on both sides of the multicylinder. The contribution rate of different transmission modes and rotation speeds to the vibration at the fundamental frequency of the multicylinder was 5%∼30%, which would also cause the deflection angle of the roller axis track to change from 1° to 5°. The frame was the main path of vibration transmission of bilateral chain drive of the multicylinder system, and the vibration transmission efficiency of the frame under different frequencies can reach more than 80%. In addition, the vibration response of each cylinder would also be transmitted to each bearing seat position of the multicylinder through the frame.
Chemical Profile, In Vitro Antioxidant, Pancreatic Lipase, and Alpha-Amylase Inhibition Assays of the Aqueous Extract of Elettaria cardamomum L. Fruits
Authors: Al-Yousef Hanan M. , Alqahtani Ali S. , Hassan Wafaa H. B. , Alzoubi Afraa , Abdelaziz Sahar
Published: May 2021

Phytochemical and pharmacological investigations of Elettaria cardamomum L. were mostly focused on its essential oil and organic crude extracts with little attention on its aqueous extracts. Therefore, the current study aimed to investigate the phytochemical profile, in vitro antiobesity, and antidiabetic activities of the aqueous extract of Elettaria cardamomum L. family Zingiberaceae. UPLC-ESI-MS/MS analysis is used for the aqueous extract characterization in both ionization modes. The analysis revealed the tentative identification of forty-seven compounds based on their MS/MS fragmentation pattern and comparison with the reported data. The identified compounds include eight flavones, thirteen phenolic and nonphenolic acids, one coumarin, and nineteen anthocyanins. Moreover, the in vitro antiobesity and antidiabetic activities were also studied. The results showed that E. cardamomum L. aqueous extract inhibits pancreatic lipase and α-amylase enzyme in a concentration-dependent manner, as 1 mg/mL extract was able to inhibit pancreatic lipase and α-amylase by 62.25% ± 0.58 (IC50 = 288.75 ± 1.3 µg/mL) and 70.42% ± 1.5 (IC50 = 220.5 ± 1.3 µg/mL), respectively. Conclusively, the current study indicated that the investigated biological activities of Elettaria cardamomum aqueous extract were attributed to the existence of biologically active metabolites such as flavones, phenolic and nonphenolic acids, coumarins, and anthocyanins. Moreover, it proposed that the aqueous cardamom extract can be used as a natural potential source in different pharmaceutical preparations to protect against variable chronic disorders, especially obesity and diabetes. Deeper in vivo investigations, isolation, purification, and structural elucidation of the major active metabolites from cardamom are recommended.