bluuebunny/crossref_metadata_2025 huggingface dataset:
An unsupervised two‐step training framework for low‐dose computed tomography denoising
Authors: Kim Wonjin , Lee Jaayeon , Choi Jang‐Hwan
Published: July 2023

Background

Although low‐dose computed tomography (CT) imaging has been more widely adopted in clinical practice to reduce radiation exposure to patients, the reconstructed CT images tend to have more noise, which impedes accurate diagnosis. Recently, deep neural networks using convolutional neural networks to reduce noise in the reconstructed low‐dose CT images have shown considerable improvement. However, they need a large number of paired normal‐ and low‐dose CT images to fully train the network via supervised learning methods.

Purpose

To propose an unsupervised two‐step training framework for image denoising that uses low‐dose CT images of one dataset and unpaired high‐dose CT images from another dataset.

Methods

Our proposed framework trains the denoising network in two steps. In the first training step, we train the network using 3D volumes of CT images and predict the center CT slice from them. This pre‐trained network is used in the second training step to train the denoising network and is combined with the memory‐efficient denoising generative adversarial network (DenoisingGAN), which further enhances both objective and perceptual quality.

Results

The experimental results on phantom and clinical datasets show superior performance over the existing traditional machine learning and self‐supervised deep learning methods, and the results are comparable to the fully supervised learning methods.

Conclusions

We proposed a new unsupervised learning framework for low‐dose CT denoising, convincingly improving noisy CT images from both objective and perceptual quality perspectives. Because our denoising framework does not require physics‐based noise models or system‐dependent assumptions, our proposed method can be easily reproduced; consequently, it can also be generally applicable to various CT scanners or dose levels.
Efficiency analysis of six‐phase induction motor drive using an optimizedSVMtechnique for medium/high power applications
Authors: Rathore Vishal , Yadav K. B.
Published: July 2023

The proposed work presents the efficiency evaluation of a six‐phase induction motor drive (SPIMD) using an optimized space‐vector modulation (SVM) scheme for medium/high power applications. An optimized SVM is obtained by resolving 5‐level hexagons into outer and inner 2‐level hexagons. In the proposed work, dual three‐phase inverters are used to drive the SPIMD, by dividing six‐phase into two, greatly reducing the calculation time, complexity, and efforts required in building the space vector control algorithm. Moreover, a comparative efficiency analysis of SPIMD using the proposed and conventionally designed SVM technique implemented with closed‐loop control is presented in this paper. Matlab/Simulink platform is used to simulate the proposed system and a prototype is developed as a proof of concept and tested experimentally to verify the analytical developments. Finally, a total harmonic distortion (THD) based comparative analysis of the proposed, conventional, and carrier‐based modulation techniques is also presented.
Effects of the combined use of segmentation or detection models on the deep learning classification performance for cyst‐like lesions of the jaws on panoramic radiographs: Preliminary research
Authors: Ariji Yoshiko , Araki Kazuyuki , Fukuda Motoki , Nozawa Michihito , Kuwada Chiaki , Kise Yoshitaka , Ariji Eiichiro
Published: July 2023

Aim

To evaluate the effects of the combined use of segmentation or detection models on the deep learning (DL) classification performance for cyst‐like lesions of the jaws on panoramic radiographs.

Methods

The panoramic radiographs of 536 patients with cyst‐like lesions of the jaws and 130 patients without cyst‐like lesions were used in this study. The radiographs were arbitrarily assigned to training, validation, and test datasets. The following three DL systems were created: System 1 directly classified cyst‐like lesions of the jaws on panoramic radiographs using a VGG‐16 convolution neural network (CNN), System 2 combined two CNNs to perform a preceding segmentation (U‐Net) and then the classification (VGG‐16), and System 3 combined two CNNs to perform a preceding detection (YOLO) and then the classification (VGG‐16). The classification performance of three systems was evaluated and compared with that of oral and maxillofacial radiologists.

Results

The classification performance of System 2 was higher than the other DL systems, demonstrating the efficacy of the combined use of DL segmentation and classification models. System 3 followed it. The radiologists showed similar accuracy with System 2 and higher performance than Systems 1 and 3. The three DL systems and the radiologists all showed higher performance for dentigerous and radicular cysts than for ameloblastoma and odontogenic keratocysts, because of bias in the number of cases between categories even if data were collected at two institutions.

Conclusions

The performance of DL classification of cyst‐like lesions of the jaws was improved by the addition of a DL segmentation technique.
Embracing paediatric palliative care in paediatric oncology from diagnosis onwards
Authors: Lacerda Ana , Martínez María Avilés , Dumont Benoît , Leiss Ulrike , Kokkinou Georgia , Scheinemann Katrin , Craig Finella
Published: July 2023

Paediatric palliative care aims to support children and young people with life‐limiting or life‐threatening conditions, and their families, from the time of diagnosis. Early integration within oncology has been recognised as having benefits for all involved, whatever the outcome may be. Through improved communication and advance care planning, it enables user‐centred care, where concerns about quality of life, preferences and values are given the same relevance as cutting‐edge therapy. Challenges to the integration of palliative care within paediatric oncology include raising awareness and providing education, whilst searching for the best care model and adapting to an ever‐changing therapeutic scenario.
Preparation and physicochemical properties of coenzyme Q10 loaded niosomal hydrogels based on carbomer and scleroglucan
Authors: Gan Changsheng , Cheng Rong , Xu Kun , Zhang Jingwen , Wang Honglei , Xu Tiantian , Li Huiya , Yang Liu
Published: July 2023

In this study, the blank hydrogels and the niosomal hydrogels loading coenzyme Q10 (CoQ10) were prepared by carbomer (CBM) and scleroglucan (SCL), and their physicochemical properties were characterized in terms of rheological and texture measurement, FTIR, SEM, DSC, and DLS. First, the blank hydrogels CBM‐SCL‐Gel were prepared. With the increase of SCL concentration, the viscosity and modulus increased, displaying better shear thinning behavior of pseudoplastic fluid. A dense network structure was formed in CBM‐SCL‐Gel, especially for CBM/SCL at 5/4 and 5/5, due to hydrogen bonding between CBM and SCL. The swelling behaviors of the composite gels conformed to pseudo‐second‐order kinetics, and CBM/SCL at 5/1 exhibited the highest swelling capability. The addition of SCL made the water absorption mechanism tend to a non‐Fickian diffusion mode. Then, the niosomal hydrogel was prepared by the optimized gel formulation with the CoQ10‐loaded niosome. It was found that the gel properties were insignificantly affected by the CoQ10 niosomes. The particle sizes of the niosomes in the gel were a little larger than that in aqueous suspension. After storage for 30 days, the CoQ10 retention rate in the niosomal gel remained at 92% (4°C, N‐Gel), representing high stability of CoQ10.
Transcriptome‐based identification and functional characterization of iridoid synthase involved in monotropein biosynthesis in blueberry
Authors: Lawas Lovely Mae F. , Kamileen Mohamed O. , Buell C. Robin , O'Connor Sarah E. , Leisner Courtney P.
Published: July 2023

Blueberries (Vaccinium spp.) are well known for their nutritional quality, and recent work has shown that Vaccinium spp. also produce iridoids, which are specialized metabolites with potent health‐promoting benefits. The iridoid glycoside monotropein, which has anti‐inflammatory and antinociceptive activities, has been detected in several wild blueberry species but in only a few cultivated highbush blueberry cultivars. How monotropein is produced in blueberry and the genes involved in its biosynthesis remain to be elucidated. Using a monotropein‐positive (M+) and monotropein‐negative (M−) cultivar of blueberry, we employed transcriptomics and comparative genomics to identify candidate genes in the blueberry iridoid biosynthetic pathway. Orthology analysis was completed using de novo transcript assemblies for both the M+ and M− blueberry cultivars along with the known iridoid‐producing plant species Catharanthus roseus to identify putative genes involved in key steps in the early iridoid biosynthetic pathway. From the identified orthologs, we functionally characterized iridoid synthase (ISY), a key enzyme involved in formation of the iridoid scaffold, from both the M+ and M− cultivars. Detection of nepetalactol suggests that ISY from both the M+ and M− cultivars produce functional enzymes that catalyze the formation of iridoids. Transcript accumulation of the putative ISY gene did not correlate with monotropein production, suggesting other genes in the monotropein biosynthetic pathway may be more directly responsible for differential accumulation of the metabolite in blueberry. Mutual rank analysis revealed that ISY is co‐expressed with UDP‐glucuronosyltransferase, which encodes an enzyme downstream of the ISY step. Results from this study contribute new knowledge in our understanding of iridoid biosynthesis in blueberry and could lead to development of new cultivars with increased human health benefits.
Topography and canopy cover influence soil organic carbon composition and distribution across a forested hillslope in the discontinuous permafrost zone
Authors: Rooney Erin C. , Bailey Vanessa L. , Patel Kaizad F. , Kholodov Alexander , Golightly Holly , Lybrand Rebecca A.
Published: July 2023

Topography and canopy cover influence ground temperature in warming permafrost landscapes, yet soil temperature heterogeneity introduced by mesotopographic slope positions, microtopographic differences in vegetation cover, and the subsequent impact of contrasting temperature conditions on soil organic carbon (SOC) dynamics are understudied. Buffering of permafrost‐affected soils against warming air temperatures in boreal forests can reflect surface soil characteristics (e.g., thickness of organic material) as well as the degree and type of canopy cover (e.g., open cover vs. closed cover). Both landscape and soil properties interact to determine meso‐ and microscale heterogeneity of ground warming. We sampled a hillslope catena transect in a discontinuous permafrost zone near Fairbanks, Alaska, to test the small‐scale (1 to 3 m) impacts of slope position and cover type on soil organic matter composition. Mineral active layer samples were collected from backslope, low backslope, and footslope positions at depths spanning 19 to 60 cm. We examined soil mineralogical composition, soil moisture, total carbon and nitrogen content, and organic mat thickness in conjunction with an assessment of SOC composition using Fourier‐transform ion cyclotron resonance mass spectrometry (FT‐ICR‐MS). Soils in the footslope position had a higher relative contribution of lignin‐like compounds, whereas backslope soils had more aliphatic and condensed aromatic compounds as determined using FT‐ICR‐MS. The effect of open versus closed tree canopy cover varied with the slope position. On the backslope, we found higher oxidation of molecules under open cover than closed cover, indicating an effect of warmer soil temperature on decomposition. Little to no effect of the canopy was observed in soils at the footslope position, which we attributed, in part, to the strong impact of soil moisture content in SOC dynamics in the water‐gathering footslope position. The thin organic mat under open cover on the backslope position may have contributed to differences in soil temperature and thus SOC oxidation under open and closed canopies. Here, the thinner organic mat did not appear to buffer the underlying soil against warm season air temperatures and thus increased SOC decomposition as indicated by the higher oxidation of SOC molecules and a lower contribution of simple molecules under open cover than the closed canopy sites. Our findings suggest that the role of canopy cover in SOC dynamics varies as a function of landscape position and soil properties, namely, organic mat thickness and soil moisture. Condition‐specific heterogeneity of SOC composition under open and closed canopy cover highlights the protective effect of canopy cover for soils on backslope positions.
Clinical features of severe Mycoplasma pneumoniae pneumonia with pulmonary complications in childhood: A retrospective study
Authors: Luo Xue qin , Luo Jian , Wang Chong jie , Luo Zheng xiu , Tian Dai yin , Xie Xiao hong
Published: July 2023

Introduction

Incidence of severe M. pneumoniae pneumonia (SMPP) reported in China has been increasing over the last decade. We aimed to evaluate the clinical features of pediatric SMPP with pulmonary complications, according to laboratory tests and chest radiographic resolution patterns.

Material and Methods

We retrospectively reviewed 93 SMPP patients between January 2016 and February 2019, and grouped them by pneumonia pattern: pulmonary complications (63 patients) and extensive lung lesions without pulmonary complications (30 patients).

Results

SMPP patients with pleural effusion (medium or large) and necrotizing pneumonia showed longer duration of fever, high serum value of lactate dehydrogenase (LDH), d‐dimer, and LDH to albumin ratio (LAR). LAR and 
d‐dimer were associated with moderate or massive pleural effusion, and 
d‐dimer was associated with lung necrosis. The average time of radiographic resolution in the pulmonary complication group was 12 weeks, while those with elevated d‐dimer were significantly more likely to have longer time for radiographic clearance.

Conclusion

We conclude that M. pneumoniae pneumonia in patients with pleural effusion (medium or large) or lung necrosis was more severe than those without pulmonary complications. LAR and 
d‐dimer might be used as parameters to identify children susceptible to pleural effusion (medium or large) or lung necrosis, and longer time for radiographic clearance among pediatric patients of SMPP.
Important safety considerations for arrangement of flammable storage tanks: Thermal radiation effects with meteorological conditions
Authors: Lee Sung‐Kyu , Lim Jae‐Yong
Published: July 2023

We examine the effects of thermal radiation on the meteorological conditions and layout of flammable liquid storage tanks. Currently, the separation distances between the tanks are dictated by regulations to prevent the domino effect of fire accidents. Although thermal radiation leads to the domino effect, it is questionable whether thermal radiation is considered in the current Korean regulations. In this study, three cases—one based on a regulation and two others associated with meteorological conditions—are considered, for which the radiation effects and tank layouts are calculated. A software program and an optimization algorithm, namely ALOHA and sequential least‐squares programming, respectively, are employed for hazard analysis and optimization, respectively. The results indicate that the current regulation is appropriate under normal meteorological conditions but may not ensure prevention of the domino effect under the worst conditions.
Dual role of endophytic entomopathogenic fungi: induce plant growth and control tomato leafminer Phthorimaea absoluta
Authors: Zheng Yaqiang , Liu Yonglan , Zhang Jinyi , Liu Xiaolong , Ju Zhigang , Shi Hongxi , Mendoza‐Mendoza Artemio , Zhou Wenwu
Published: July 2023

BACKGROUND

Entomopathogenic fungi (EPF) are multifunctional microorganisms acting not only as biopesticides against insect pests but also as endophytes which regulate plant growth. The tomato leafminer, Phthorimaea absoluta (Tuta absoluta) is a devastating invasive pest of tomatoes worldwide. However, effective alternatives are needed for a sustainable management of this invasive pest. In this study, the functional effects of five EPF isolates Metarhizium flavoviride, M. anisopliae, M. rileyi, Cordyceps fumosorosea and Beauveria bassiana were evaluated on tomato growth promotion and pest protection against P. absoluta.

RESULTS

When directly sprayed with conidia, P. absoluta larvae showed high cumulative mortality of 100% to M. anisopliae under 1 × 108 conidia/mL, whereas M. flavoviride, B. bassiana, C. fumosorosea and M. rileyi caused cumulative mortality of 92.65%, 92.62%, 92.16% and 68.95%, respectively. Moreover, all five EPF isolates can successfully colonize tomato plants, whilst the colonization rate for each EPF depends on the inoculation method used. The most efficient inoculation method for M. flavoviride and M. rileyi was root dipping, for M. anisopliae and C. fumosorosea it was coating seed, and for B. bassiana it was foliage spraying. The highest plant colonization was obtained by M. flavoviride. Meanwhile, all these isolates promoted tomato plant growth upon inoculation. Furthermore, endophytic colonization of plants by the five EPF negatively affected the performance of P. absoluta, among them M. anisopliae and C. fumosorosea showed strong negative effects on the performance of P. absoluta.

CONCLUSION

Our results highlight the potential of incorporating entomopathogenic fungi as endophytes in integrated pest management practices to protect tomatoes against P. absoluta. © 2023 Society of Chemical Industry.
Assessment of spilled toxic bait by wild pigs and potential risk to non‐target species
Authors: Kinsey John C , Foster Justin A , Snow Nathan P , Wishart Jason D , Staples Linton D , Bush Janis K , VerCauteren Kurt C
Published: July 2023

Background

In 2018, a sodium nitrite (SN)‐based toxic bait for invasive wild pigs (hereafter wild pigs; Sus scrofa), was evaluated to determine its effectiveness in reducing local wild pig populations in Texas. Localized population reductions of >70% were achieved, but spillage of bait outside wild pig‐specific feeders (bait stations) caused by feeding wild pigs resulted in the deaths of non‐target animals. To evaluate risks to non‐target animals, we tested whether bait presentation influenced the total amount of bait spilled by wild pigs and estimated the associated risk to non‐target species.

Results

We found that bait spilled outside bait stations could be reduced by >90% when compacted in trays, as opposed to being manually crumbled into pieces. We documented a mean spill rate of 0.913 g of bait per wild pig. Conservative risk assessments for nine non‐target species for which SN toxicity data exist indicate that there is relatively low risk of lethal exposure, apart from zebra finches (Taeniopygia guttata) and white mice. Our results indicate that there may be enough spilled bait per feeding wild pig to kill 9.5 or 3.5 individuals of these species, respectively. Other species assessed range from 0.002 to 0.406 potential mortalities per wild pig.

Conclusion

We demonstrated that the amount of bait spilled by wild pigs during feeding and the associated risk to non‐target animals can be minimized by presenting the bait compacted in trays within bait stations. We recommend that baits be tightly compacted and secured in bait stations to minimize risks to non‐target animals from spilled bait by wild pigs. © 2023 Society of Chemical Industry. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
Distributed optimal coordination of uncertain nonlinear multi‐agent systems over unbalanced directed networks via output feedback
Authors: Zhang Jin , Liu Lu , Wang Xinghu , Ji Haibo
Published: July 2023

In this article, a novel observer‐based output feedback control approach is proposed to address the distributed optimal coordination problem of uncertain nonlinear multi‐agent systems in the normal form over unbalanced directed graphs. The main challenges of the concerned problem lie in unbalanced directed graphs and nonlinearities of multi‐agent systems with their agent states not available for feedback control. Based on a two‐layer controller structure, a distributed optimal coordinator is first designed to convert the considered problem into a reference‐tracking problem. Then a decentralized output feedback controller is developed to stabilize the resulting augmented system. A high‐gain observer is exploited in controller design to estimate the agent states in the presence of uncertainties and disturbances so that the proposed controller relies only on agent outputs. The semi‐global convergence of the agent outputs toward the optimal solution that minimizes the sum of all local cost functions is proved under standard assumptions. A key feature of the obtained results is that the nonlinear agents under consideration are only required to be locally Lipschitz and possess globally asymptotically stable and locally exponentially stable zero dynamics.
Secondary school students' responses to epistemic uncertainty during an ecological citizen science inquiry
Authors: Kervinen Anttoni , Aivelo Tuomas
Published: July 2023

Uncertainty is endemic to scientific research practices; therefore, it is also an important element in learning about science. Studies have shown that experiences and management of uncertainty regarding the epistemic practices of science can support learning. Whereas the common strategies of supporting students in handling uncertainty rely on the teacher knowing the preferred outcomes and answers, few studies have explored settings in which no one can give the right answers to students. In this study, we explore how Finnish, suburban secondary school students (aged 13–14 years) respond to epistemic uncertainty during an ecological citizen science inquiry, in which the aim is to produce novel scientific knowledge. Drawing from qualitative interaction analysis of video and interview data, we articulate three responses to uncertainty that arise when students try to make optimal choices during the inquiry: they (a) envision alternative narrative scenarios and hypothesis; (b) accept and maintain it as part of their argumentation practices, and (c) flexibly reframe their research activities and goals. The findings indicate that the citizen science setting can allow students to reframe epistemic uncertainty in ways that are typical of scientific practices even without deliberate scaffolding by the teacher. We suggest that incorporating experiences of uncertainty that are shared by students and teachers in pedagogical design can support doing and learning science in different settings.
Exploring the impacts of spatial regulation on environmentally sustainable development: A new perspective of quasi–experimental evaluation based on the National Key Ecological Function Zones in China
Authors: Chen Chaofan , Li Wen‐Bo , Zheng Lijuan , Guan Chenghua
Published: July 2023

With increasing ecological damage caused by regional development, many countries seek to promote sustainable development through spatial regulation. This study treated China's development of National Key Ecological Functional Zones (NKEFZ) as a quasi–natural experiment, applying a time–varying difference–in–differences model to data from 148 water quality monitoring cross–section points of major river systems in China from 2004 to 2018. The results revealed that NKEFZ improved the mean of comprehensive water quality (CWQ) and individual water quality indicators of dissolved oxygen and ammonia nitrogen content index by restricting urbanization and increasing government investment. The mean value of CWQ was improved by about 0.22 grades, and the optimization effect of spatial regulation on average water quality was more prominent in coastal cities, cities with high–pollution levels, and large–sized cities. Nevertheless, the impact of NKEFZ on water quality exhibited a “Matthew effect”, in which NKEFZ were not effective in improving the bottom line standard of water quality in the pilot zones, as NKEFZ did not significantly improve the peak values of CWQ or individual pollutant indicator. In addition, an economic effect estimation indicated that NKEFZ significantly facilitated local economic growth and primary industry development and had a significantly negative impact on secondary industry growth and foreign investment. This study contributes new evidence for measuring the effect of the trans–regional spatial regulation, eliciting policy implications for improving ecological spatial regulation and incentive mechanisms, and promoting the sustainable development of the regional environment and economy.
Nanopesticides: A Review on Current Research and Future Perspective
Authors: Paradva Krish Chunilal , Kalla Sarita
Published: July 2023

The survival of humans depends critically on crop production, making crop protection absolutely essential. Numerous studies have suggested that nanopesticides could soon fully replace conventional pesticides since they are far more effective than those now in use. Due to an increase in their surface‐to‐volume ratio, nanomaterials exhibit different properties from their bulk counterparts. Nanopesticides are pesticides that have been made with these nanoparticles and have a high application efficiency and significantly fewer hazardous environmental impacts than pesticides that have been made chemically. Various formulation strategies, which include the containment of the active substance by the nanoparticles, have previously been established, exhibiting promising effects on the pests. Target specificity, high stability, and controlled active ingredients (AIs) release are a few of the noteworthy qualities these nanopesticides offer. The development of green nanopesticides derived from nature, which have very low ecotoxicities and nanoscale qualities, can also have a significant positive impact on crop output. However, before being mass‐produced and used, the discovery still has to be thoroughly examined to determine its effects on people and the environment due to the lack of conclusive proof demonstrating its toxicity. This paper aims to represent the use of nanopesticides in crop protection and a detailed overview of the various methods for the formulation of nanopesticides. Also, the possible negative impacts on the non‐target species by the application of nanopesticides have been briefly discussed. The need for the development of green nanopesticides to avoid the negative aspects of nanopesticides has also been highlighted.
Fused Imidazo[2,1‐b][1,2,3]triazolo[4,5‐d][1,3]thiazines: One‐Pot Synthesis, Antibiofilim, Bactericidal Effects, and in silico Studies
Authors: Ramu Nagavelli , Krishna Thupurani Murali , Nasipireddy Venkatarathnam , Kapavarapu Ravikumar , Narsimha Sirassu
Published: July 2023

It has been reported that biologically active organic probe underwent a highly adaptive, efficient and selective “Click followed by C−N bond coupling” by the use of PEG‐400 in microwave irradiation. In less time and with good to excellent yields, this method enables the synthesis of fused 1,2,3‐triazoles via Cu(I)‐catalyzed cycloaddition and C−N bond coupling. Later, Minimum Inhibitory Concentration of the synthesized compounds (5 a–5 o) was determined against three Staphylococcus aureus mutant strains by the broth dilution method. The obtained results were compared with standard drugs Clindamycin and Dicloxacillin. Among the compounds investigated, 1‐(3,5‐dimethoxyphenyl)‐1,4‐dihydroimidazo[2,1‐b] [1,2,3]triazolo[4,5‐d] [1,3] thiazine 5,5‐dioxide (5 c), 1‐(3,4,5‐trimethoxyphenyl)‐1,4‐dihydro imidazo[2,1‐b][1,2,3]triazolo[4,5‐d][1,3]thiazine 5,5‐dioxide (5 d), 1‐(4‐chloro‐3,5‐dimethoxyphenyl)‐1,4‐dihydroimidazo[2,1‐b][1,2,3]triazolo [4,5‐d][1,3]thiazine 5,5‐dioxide (5 e), 1‐(3,5‐dichlorophenyl)‐1,4‐dihydroimidazo[2,1‐b][1,2,3]triazolo[4,5‐d][1,3]thiazine 5,5‐dioxide (5 h), 1‐(4‐(trifluoromethyl)phenyl)‐1,4‐dihydroimidazo[2,1‐b][1,2,3]triazolo [4,5‐d][1,3]thiazine 5,5‐dioxide (5 m), and 1‐(4‐(trifluoromethoxy) phenyl)‐1,4‐dihydroimidazo[2,1‐b][1,2,3]triazolo[4,5‐d][1,3]thiazine 5,5‐dioxide (5 n) demonstrated the most promising Minimum Inhibitory Concentration values comparing to others. The MIC values were ranged from 1.56 μg to 12.5 μg, especially compounds 5 c, 5 d, and 5 e displayed superior activity against tested strains compared to the standards. We also documented the results of anti‐biofilm profiles for the compounds 5 c, 5 d, 5 e, 5 h, 5 m and 5 n. Based on the result, we noted that, the active derivatives 5 c, 5 d, and 5 e were strongly inhibited the biofilm of MSSA and MRSA biofilm growth with BFIC values ranging from 3.34±0.05 to 8.32±0.32 μg/mL. In accordance to the results of antibiofilm property, the compounds 5 c, 5 d and 5 e were further evaluated for bactericidal effect against selected Staphylococcus aureus mutant strains. In concern to the results, we confirmed that, the bactericidal effect was found significant with compound 5 d and followed by 5 c and 5 e. In silico docking simulation studies were performed to evaluate the molecular interactions of 5 c, 5 d, 5 e, 5 h, 5 m and 5 n compounds with the S.aureus (MRSA), Penicillin‐binding protein (PDB ID: 1MWT, co‐crystallised ligand inhibitor Pencillin G). Finally, the in silico pharmacokinetic profile was predicted for potent compounds using SWISS/ADME and pkCSM.
Highly Regioselective Synthesis of 3,6‐Diaryl‐2‐(het)arylpyridines by aza‐Diels‐Alder Reactions between 6‐H‐1,2,4‐Triazine Dienes and 2‐Amino‐4‐aryloxazole‐Based Dienophiles
Authors: Shtaitz Yaroslav K. , Rammohan Aluru , Krinochkin Alexey P. , Ladin Evgeny D. , Butorin Ilya I. , Mochulskaya Nataliya N. , Khalymbadzha Igor A. , Slepukhin Pavel A. , Shevyrin Vadim A. , Kopchuk Dmitry S. , Zyryanov Grigory V. , Chupakhin Oleg N.
Published: July 2023

A solvent‐free reaction between C6‐unsubstituted 5‐aryl‐1,2,4‐triazines and 2‐amino‐4‐aryloxazoles at high temperature was studied. The reaction proceeds via inverse electron demand aza‐Diels‐Alder reaction between the oxazole moiety as dienophile and the 1,2,4‐triazine moiety as diene with the highly regioselective formation of 3,6‐diarylpyridines in up to 60 % isolated yield. The structure of one of the key‐products was proven by the X‐ray diffraction analysis, and the mechanism of the transformation was proposed. The reaction proceeds well for both 6‐aryl and 6‐hetaryl‐1,2,4‐triazines in the presence of the electron acceptor substituent at the position 3. In the case of the donor substituent in position 3, the pyridine yields are significantly reduced. In the case of 5,6‐nonsubstituted 1,2,4‐triazines, the triazine cycle is degraded without product formation. The high regioselectivity of the reaction as well as solvent‐free conditions are valuable advantages of the present synthetic approach.
Recent Developments towards the Synthesis of Pyrimidopyrimidine and Purine Derivatives
Authors: Debnath Pradip
Published: July 2023

Fused pyrimidines scaffolds such as pyrimidopyrimidines, purines and xanthines are important structural motifs found in various natural products and drug molecules. They are used as anticancer, antiviral, antibacterial, antifungal, antioxidant, antitumor, anti‐diabetic, adenosine potentiating, and hepatoprotective agents. Due to their diverse biological applications, the synthesis of pyrimidopyrimidines, purines and xanthines has gained great importance among the researchers in recent years. Thus, the present study aims to review the synthetic methodologies published during the years 2000–2022 for the preparation of pyrimidopyrimidines, purines and xanthines nucleus. Mechanistic interpretation of some important cases has also been discussed. This survey will help researchers working in the fields of synthetic organic and medicinal chemistry to undertake and improve new approaches for the construction of titled compounds.
Structure‐Based Virtual Screening, ADMET analysis, and Molecular Dynamics Simulation of Moroccan Natural Compounds as Candidates α‐Amylase Inhibitors
Authors: Abchir Oussama , Yamari Imane , Nour Hassan , Daoui Ossama , Elkhattabi Souad , Errougui Abdelkbir , Chtita Samir
Published: July 2023

Current treatments for diabetes mellitus are ineffective, as evidenced by the rise in diabetes cases. This has forced researchers to develop novel chemicals as drugs to block the enzyme alpha‐amylase as the severe way to treat diabetes disease. Many previous studies were done to determine the biological activity of a set of molecules isolated from medicinal plants. Morocco is renowned for the abundance of plants it has and for the traditional medical uses of these plants, which drives us to employ our cultural heritage and the variety of our nation‘s natural resources in the therapeutic area. In the current study, extensive research was conducted to compile a group of phytoconstituents derived from Moroccan plants and used in conventional Moroccan medicine to treat local illnesses. To assess the stability of the generated complexes, molecular docking of the investigated compounds was carried out in the active site of 4 distinct alpha‐amylase proteins. The remaining compounds with a high negative binding affinity were then subjected to the ADMET analysis to determine their pharmacological characteristics. The findings showed that two drugs have strong binding affinity for the target proteins and may be used orally as potential alpha‐amylase inhibitors. The results of molecular dynamics analysis and MMGBSA calculation were used to validate the optimal stability of created complexes (L97 with studied proteins 1HNY, 1OSE, 1UA7 and 1BAG).
A Cyclic Phosphonium Ion with an Asymmetrically Substituted Selenide‐Stabilized Silicon Center: Synthesis, Structure, and Substituent Effects
Authors: Fontana Nicolò , Bauer Jonathan O.
Published: July 2023

A new heterocyclic four‐membered CPSeSi cation was synthesized in its racemic form by B(C6F5)3‐mediated ring‐closing reaction starting from the hydrosilane precursor. The cation has an asymmetrically substituted silicon center, which is stabilized by a selenium–silicon bond. The phosphonium hydroborate and its precursor were characterized by single‐crystal X‐ray diffraction analysis and NMR spectroscopy. 77Se, 31P, and 29Si NMR spectroscopic parameters proved to be sensitive probes for determining small electronic changes around the silylium‐type center. Density functional theory (DFT) calculations of the ring‐opening energy of the selenium‐based cation gave insight into the stability of the Se–Si bond and revealed a stronger intramolecular stabilization of the silicon atom compared to a coordinating phosphane sulfide function. For the first time, the influence of a C6F5 group at the silicon atom of these type of cations was also investigated, showing a slightly increased stabilization of the Se–Si linkage in the cyclic selenium‐based cation.
Synthesis and Crystal Structures of 4‐Methoxyphenyl‐ N‐phenylhydrazine‐1‐carbothioamide isomers and 2,2’‐(1,2,4,5‐tetrazine‐3,6‐diyl) bis (N‐phenylhydrazine‐1‐carbothioamide)
Authors: Gettings Matthew L. , Zeller Matthias , Piercey Davin G.
Published: July 2023

The synthesis of several semithiocarbazides, relevant as a precursor material for the synthesis of the tetrazole azasydnone, a potential energetic material, was explored. In this work, the treatment of 4‐methoxy phenylhydrazine hydrochloride with phenyl isothiocyanate results in 2‐ and 1‐ isomers of (4‐methoxyphenyl)‐N‐phenylhydrazine‐1‐carbothioamide. Similar treatment of 3,6,–dihydrazino‐1,2,4,5‐tetrazine with phenyl isothiocyanate yielded 2,2’‐(1,2,4,5‐tetrazine‐3,6‐diyl) bis (N‐phenylhydrazine‐1‐carbothioamide). Crystallographic information for all novel compounds was obtained via single crystal X‐ray diffraction.
PtMo‐Au Metalloenzymes Regulated Tumor Microenvironment for Enhanced Sonodynamic/Chemodynamic/Starvation Synergistic Therapy
Authors: Zhu Jiawei , Wang Chenxi , Wei Qinglin , Su Yan , Qu Xinyu , Wang Wenjun , Song Xuejiao , Dong Xiaochen , Cai Yu
Published: July 2023

The clinical application of sonodynamic therapy (SDT) is greatly limited by the low quantum yield of sonosensitizers and tumor microenvironment (TME). Herein, PtMo‐Au metalloenzyme sonosensitizer is synthesized by modulating energy band structure of PtMo with Au nanoparticles. The surface deposition of Au simultaneously solves the carrier recombination and facilitates the separation of electrons (e−) and holes (h+), effectively improving the reactive oxygen species (ROS) quantum yield under ultrasound (US). The catalase‐like activity of PtMo‐Au metalloenzymes alleviates hypoxia TME, thus enhancing the SDT‐induced ROS generation. More importantly, tumor overexpressed glutathione (GSH) can serve as the hole scavenger, which is accompanied by a persistent depletion of the GSH, thus inactivating GPX4 for the accumulation of lipid peroxides. The distinctly facilitated SDT‐induced ROS production is coupled with chemodynamic therapy (CDT)‐induced hydroxyl radicals (•OH) to exacerbate ferroptosis. Furthermore, Au with glucose oxidase mimic activity can not only inhibit intracellular adenosine triphosphate (ATP) production and induce tumor cell starvation but also generate H2O2 to facilitate CDT. In general, this PtMo‐Au metalloenzyme sonosensitizer optimizes the defects of conventional sonosensitizers through surface deposition of Au to regulate TME, providing a novel perspective for US‐based tumor multimodal therapy.
Adult branchiosaurid temnospondyls: the life cycle of Xerodromeus gracilis
Authors: Schoch Rainer R. , Werneburg Ralf
Published: July 2023

The Branchiosauridae form a clade of tiny newt‐like, extinct amphibians of overall larval appearance. Although their status as neotenic (perennibranchiate) forms had long been universally accepted, adult specimens are known from only one taxon that was hitherto referred to as Melanerpeton (Apateon) gracile. Here we study this life cycle in depth, which includes the only well‐documented metamorphosis‐like transformation in an early tetrapod outside Lissamphibia. Based on various newly recognized features, Melanerpeton gracile is attributed to a new genus, Xerodromeus. Xerodromeus gracilis is characterized by a short postorbital skull table, wide supratemporal, quadrate condyles well posterior to the occipital ones, ossified endocranial elements, carpals, coracoid and pelvis as well as wedge‐shaped intercentra and cylindrical pleurocentra, of which the latter are identified for the first time in branchiosaurids. The studied size classes are referred to four phases: (A) integration of jaw and cheek, longer snout; (B) stronger teeth, robust limbs, incipient ossification of exoccipital, coracoid and pelvis, change in dermal ornament; (C) larger gape, wider skull, polygonal ornament; and (D) quadrate, coracoid, carpals and vertebral centra ossified, during which a probably terrestrial adult morph developed. Adult X. gracilis is more massively built than amphibamids, and its non‐pedicellate dentition indicates that it was probably feeding on different prey.
Micro‐Doppler Radar‐Based Gait Classification of Common Pedestrians and Smartphone Zombies
Authors: Yasuda Kazuki , Tsuyuhara Teppei , Saho Kenshi , Masugi Masao
Published: July 2023

This paper proposes a micro‐Doppler radar‐based method to classify common pedestrians and pedestrians texting on a smartphone (called a smartphone zombies). We used a micro‐Doppler radar to collect motion data of the gait of participants texting on smartphones while walking, and then generated time‐frequency distribution images (spectrogram images). They were input into a convolutional neural network (CNN) to classify gait patterns. Results using measured data confirmed that the classification accuracy exceeded 90%, validating the effectiveness of the proposed method. Furthermore, by applying feature visualization by Grad‐Cam, we found that the motion of the leg swinging has essential features for the classification of smartphone zombies. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.
Artificial DNA in hydrology
Authors: Foppen Jan Willem
Published: July 2023

The use of artificial DNA (artDNA) in hydrological applications is becoming increasingly popular, either in dissolved form (dissolved artDNA) or encapsulated and protected by a layer (encDNA). DNA can be detected even at low concentrations and offers the ability to create numerous uniquely identifiable DNA labels, making it ideal for a wide range of multi‐tracer applications. A literature review revealed that in streams, the breakthrough curve of artDNA is visually similar to that of a conservative tracer in terms of time to rise, time to peak, and dispersion coefficient. In saturated porous or fractured media, the time of first arrivals and time to peak of artDNA are usually earlier than that of a conservative tracer, indicating size exclusion of both dissolved artDNA and encDNA. Transport in subsurface media can be described by one‐site or two‐site kinetic attachment. The recovery of artDNA in environmental systems is always less than 100% due to adsorption and decay. Although the processes responsible for both are known, yet they cannot be quantified or predicted in mass balance approaches. Despite these limitations, artDNA can be used in various hydrological applications in environmental studies and engineering. Finally, attention should focus on the use of rapid detection of DNA tracers in the field, on upscaling of DNA production, and on increasing the efficiency of the DNA encapsulation process.

This article is categorized under:

Science of Water > Hydrological Processes

Science of Water > Water Quality

Science of Water > Methods
Diskussion der Ergebnisse – Schulleiter/-innen zwischen Legitimitätsansprüchen und Transformationsstreben
Authors: Jesacher-Rößler Livia
Published: July 2023

Ausgehend von der Annahme, dass schulische Umwelten aus institutionalisierten Erwartungsstrukturen bestehen, die Einfluss auf die Ausgestaltung und Abläufe von Entwicklungsprozessen innerhalb schulischer Organisationen nehmen (vgl. Walgebach & Meyer 2008, S. 11), wird in der vorliegenden Arbeit das Antwortgeschehen von Schulleiter/-innen auf institutionelle Ansprüche untersucht. Besonders sichtbar wird ein solches Antwortgeschehen, wenn neue Erwartungen aus der institutionalisierten Umwelt an die schulischen Organisationen herangetragen werden, beispielsweise im Zuge von Reformen. Von diesen Grundprämissen ausgehend, werden nachfolgend zentrale Ergebnisse der Studie unter Rückbindung an neo-institutionalistische Zugänge sowie im Kontext von Schulentwicklungs- und Schulleitungsforschung diskutiert.
A comparison of four liquid chromatography–mass spectrometry platforms for the analysis of zeranols in urine
Authors: Lazofsky Abigail , Brinker Anita , Rivera-Núñez Zorimar , Buckley Brian
Published: July 2023

Targeted biomonitoring studies quantifying the concentration of zeranols in biological matrices have focused on liquid chromatography interfaced to mass spectrometry (LC–MS). The MS platform for measurement, quadrupole, time-of-flight (ToF), ion trap, etc., is often chosen based on either sensitivity or selectivity. An instrument performance comparison of the benefits and limitations using matrix-matched standards containing 6 zeranols on 4 MS instruments, 2 low-resolution (linear ion traps), and 2 high-resolution (Orbitrap and ToF) was undertaken to identify the best measurement platform for multiple biomonitoring projects characterizing the endocrine disruptive properties of zeranols. Analytical figures of merit were calculated for each analyte to compare instrument performance across platforms. The calibration curves had correlation coefficients r = 0.989 ± 0.012 for all analytes and LODs and LOQs were ranked for sensitivity: Orbitrap > LTQ > LTQXL > G1 (V mode) > G1 (W mode). The Orbitrap had the smallest measured variation (lowest %CV), while the G1 had the highest. Instrumental selectivity was calculated using full width at half maximum (FWHM) and as expected, the low-resolution instruments had the broadest spectrometric peaks, concealing coeluting peaks under the same mass window as the analyte. Multiple peaks from concomitant ions, unresolved at low resolution (within a unit mass window), were present but did not match the exact mass predicted for the analyte. For example, the high-resolution platforms were able to differentiate between a concomitant peak at 319.1915 from the analyte at 319.1551, included in low-resolution quantitative analyses demonstrating the need to consider coeluting interfering ions in biomonitoring studies. Finally, a validated method using the Orbitrap was applied to human urine samples from a pilot cohort study.
“In Vitro” Evaluation of Energy‐Based Sealing of Graft Side Branches in Bypass Surgery
Authors: Miralles Manuel , Falcón Moisés , Requejo Lucía , Plana Emma , Medina Pilar , Sánchez‐Nevárez Ignacio , Clará Albert
Published: July 2023

Introduction

Our objective was to compare the in vitro efficacy of electrothermal bipolar [EB] vessel sealing and ultrasonic harmonic scalpel [HS] versus mechanical interruption, with conventional ties or surgical clips (SC), in sealing saphenous vein (SV) collaterals, during its eventual preparation for bypass surgery.

Methods

Experimental in vitro study on 30 segments of SV. Each fragment included two collaterals at least 2 mm in diameter. One of them was sealed by ligation with 3/0 silk ties (control) and the other one with EB (n = 10), HS (n = 10) or medium‐6 mm SC (n = 10). After incorporation in a closed circuit with pulsatile flow, the pressure was progressively increased until causing rupture. Collateral diameter, burst pressure, leak point, and histological study were recorded.

Results

Burst pressure was higher for SC (1320.20 ± 373.847 mmHg) as compared with EB (942.2 ± 344.9 mmHg, p = 0.065), and especially with HS (637.00 ± 320.61 mmHg, p = 0.0001). No statistically significant difference between EB and HS was found, and bursting always happened at supraphysiological pressures. The leak point for HS was always detected in the sealing zone (10/10), while for EB and SC, it occurred in the sealing zone only in 6/10(60%) and 4/10(40%), respectively (p = 0.015).

Conclusions

Energy delivery devices showed similar efficacy and safety in sealing of SV side branches. Although bursting pressure was lower than with tie ligature or SC, non‐inferiority efficacy was shown at the range of physiological pressures in both, EB and HS. Due to their speed and easy handling, they may be useful in the preparation of the venous graft during revascularization surgery. However, remaining questions about healing process, potential spread of tissue damage and sealing durability, will require further analysis.
Survey and systematization of 3D object detection models and methods
Authors: Drobnitzky Moritz , Friederich Jonas , Egger Bernhard , Zschech Patrick
Published: July 2023

Strong demand for autonomous vehicles and the wide availability of 3D sensors are continuously fueling the proposal of novel methods for 3D object detection. In this paper, we provide a comprehensive survey of recent developments from 2012–2021 in 3D object detection covering the full pipeline from input data, over data representation and feature extraction to the actual detection modules. We introduce fundamental concepts, focus on a broad range of different approaches that have emerged over the past decade, and propose a systematization that provides a practical framework for comparing these approaches with the goal of guiding future development, evaluation, and application activities. Specifically, our survey and systematization of 3D object detection models and methods can help researchers and practitioners to get a quick overview of the field by decomposing 3DOD solutions into more manageable pieces.