bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineered CRISPR-Cas12a for higher-order combinatorial chromatin perturbations
Authors: Hsiung C. C.-S. , Wilson C. M. , Sambold N. A. , Dai R. , Chen Q. , Teyssier N. , Misiukiewicz S. , Arab A. , O’Loughlin T. , Cofsky J. C. , Shi J. , Gilbert L. A.
Published: May 2024

Multiplexed genetic perturbations are critical for testing functional interactions among coding or non-coding genetic elements. Compared to double-stranded DNA cutting, repressive chromatin formation using CRISPR interference (CRISPRi) avoids genotoxicity and is more effective for perturbing non-coding regulatory elements in pooled assays. However, current CRISPRi pooled screening approaches are limited to targeting one to three genomic sites per cell. We engineer an Acidaminococcus Cas12a (AsCas12a) variant, multiplexed transcriptional interference AsCas12a (multiAsCas12a), that incorporates R1226A, a mutation that stabilizes the ribonucleoprotein–DNA complex via DNA nicking. The multiAsCas12a-KRAB fusion improves CRISPRi activity over DNase-dead AsCas12a-KRAB fusions, often rescuing the activities of lentivirally delivered CRISPR RNAs (crRNA) that are inactive when used with the latter. multiAsCas12a-KRAB supports CRISPRi using 6-plex crRNA arrays in high-throughput pooled screens. Using multiAsCas12a-KRAB, we discover enhancer elements and dissect the combinatorial function of cis-regulatory elements in human cells. These results instantiate a group testing framework for efficiently surveying numerous combinations of chromatin perturbations for biological discovery and engineering.
p75 neurotrophin receptor modulation in mild to moderate Alzheimer disease: a randomized, placebo-controlled phase 2a trial
Authors: Shanks Hayley R. C. , Chen Kewei , Reiman Eric M. , Blennow Kaj , Cummings Jeffrey L. , Massa Stephen M. , Longo Frank M. , Börjesson-Hanson Anne , Windisch Manfred , Schmitz Taylor W.
Published: May 2024

p75 neurotrophin receptor (p75NTR) signaling pathways substantially overlap with degenerative networks active in Alzheimer disease (AD). Modulation of p75NTR with the first-in-class small molecule LM11A-31 mitigates amyloid-induced and pathological tau-induced synaptic loss in preclinical models. Here we conducted a 26-week randomized, placebo-controlled, double-blinded phase 2a safety and exploratory endpoint trial of LM11A-31 in 242 participants with mild to moderate AD with three arms: placebo, 200 mg LM11A-31 and 400 mg LM11A-31, administered twice daily by oral capsules. This trial met its primary endpoint of safety and tolerability. Within the prespecified secondary and exploratory outcome domains (structural magnetic resonance imaging, fluorodeoxyglucose positron-emission tomography and cerebrospinal fluid biomarkers), significant drug–placebo differences were found, consistent with the hypothesis that LM11A-31 slows progression of pathophysiological features of AD; no significant effect of active treatment was observed on cognitive tests. Together, these results suggest that targeting p75NTR with LM11A-31 warrants further investigation in larger-scale clinical trials of longer duration. EU Clinical Trials registration: 2015-005263-16; ClinicalTrials.gov registration: NCT03069014.
Unwinding of a eukaryotic origin of replication visualized by cryo-EM
Authors: Henrikus Sarah S. , Gross Marta H. , Willhoft Oliver , Pühringer Thomas , Lewis Jacob S. , McClure Allison W. , Greiwe Julia F. , Palm Giacomo , Nans Andrea , Diffley John F. X. , Costa Alessandro
Published: May 2024

To prevent detrimental chromosome re-replication, DNA loading of a double hexamer of the minichromosome maintenance (MCM) replicative helicase is temporally separated from DNA unwinding. Upon S-phase transition in yeast, DNA unwinding is achieved in two steps: limited opening of the double helix and topological separation of the two DNA strands. First, Cdc45, GINS and Polε engage MCM to assemble a double CMGE with two partially separated hexamers that nucleate DNA melting. In the second step, triggered by Mcm10, two CMGEs separate completely, eject the lagging-strand template and cross paths. To understand Mcm10 during helicase activation, we used biochemical reconstitution with cryogenic electron microscopy. We found that Mcm10 splits the double CMGE by engaging the N-terminal homo-dimerization face of MCM. To eject the lagging strand, DNA unwinding is started from the N-terminal side of MCM while the hexamer channel becomes too narrow to harbor duplex DNA.
Enhanced optical and electrochemical properties of FeBTC MOF modified TiO2 photoanode for DSSCs application
Authors: Moloto William , Mbule Pontsho , Nxumalo Edward , Ntsendwana Bulelwa
Published: May 2024

In this work, iron based 1, 3, 5-tricarboxylic acid (FeBTC) was prepared via microwave-assisted method and incorporated into TiO2 via ultrasonic assisted method. The TiO2–FeBTC nanocomposites were characterized by XRD, FTIR, Raman, BET, FESEM, HRTEM, TGA, UV‒vis DRS and PL to understand their crystallographic, surface morphology, and optical characteristics. The Raman spectra showed a blue shift of Eg, A1g, and B1g peaks upon incorporation of FeBTC MOF onto TiO2. HRTEM and XRD analysis confirmed a mixture of TiO2 nanospheres and hexagonal FeBTC MOF morphologies with high crystallinity. The incorporation of FeBTC onto TiO2 improved the surface area as confirmed by BET results, which resulted in improved absorption in the visible region as a results of reduced bandgap energy from 3.2 to 2.84 eV. The PL results showed a reduced intensity for TiO2–FeBTC (6%) sample, indicating improved separation of electron hole pairs and reduced recombination rate. After fabrication of the TiO2–FeBTC MOF photoanode, the charge transfer kinetics were enhanced at TiO2–FeBTC MOF (6%) with Rp value of 966 Ω, as given by EIS studies. This led to high performance due to low charge resistance. Hence, high power conversion efficiency (PCE) value of 0.538% for TiO2–FeBTC (6%) was achieved, in comparison with other loadings. This was attributed to a relatively high surface area which allowed more charge shuttling and thus better electrical response. Conversely, upon increasing the FeBTC MOF loading to 8%, significant reduction in efficiency (0.478%) was obtained, which was attributed to sluggish charge transfer and fast electron–hole pair recombination rate. The TiO2–FeBTC (6%) may be a good candidate for use in DSSCs as a photoanode materials for improved efficiency.
Tea and Pleurotus ostreatus intercropping modulates structure of soil and root microbial communities
Authors: Yang Zhengkai , Qu Jiaojiao , Qiao Lu , Jiang Meiling , Zou Xiao , Cao Wei
Published: May 2024

Intercropping with Pleurotus ostreatus has been demonstrated to increase the tea yield and alleviate soil acidification in tea gardens. However, the underlying mechanisms remain elusive. Here, high-throughput sequencing and Biolog Eco analysis were performed to identify changes in the community structure and abundance of soil microorganisms in the P. ostreatus intercropped tea garden at different seasons (April and September). The results showed that the soil microbial diversity of rhizosphere decreased in April, while rhizosphere and non-rhizosphere soil microbial diversity increased in September in the P. ostreatus intercropped tea garden. The diversity of tea tree root microorganisms increased in both periods. In addition, the number of fungi associated with organic matter decomposition and nutrient cycling, such as Penicillium, Trichoderma, and Trechispora, was significantly higher in the intercropped group than in the control group. Intercropping with P. ostreatus increased the levels of total nitrogen (TN), total phosphorus (TP), and available phosphorus (AP) in the soil. It also improved the content of secondary metabolites, such as tea catechins, and polysaccharides in tea buds. Microbial network analysis showed that Unclassified_o__Helotiales, and Devosia were positively correlated with soil TN and pH, while Lactobacillus, Acidothermus, and Monascus were positively correlated with flavone, AE, and catechins in tea trees. In conclusion, intercropping with P. ostreatus can improve the physical and chemical properties of soil and the composition and structure of microbial communities in tea gardens, which has significant potential for application in monoculture tea gardens with acidic soils.
Investigation of rank order centroid method for optimal generation control
Authors: Varshney T. , Waghmare A. V. , Singh V. P. , Ramu M. , Patnana N. , Meena V. P. , Azar Ahmad Taher , Hameed Ibrahim A.
Published: May 2024

Multi-criteria decision-making (MCDM) presents a significant challenge in decision-making processes, aiming to ascertain optimal choice by considering multiple criteria. This paper proposes rank order centroid (ROC) method, MCDM technique, to determine weights for sub-objective functions, specifically, addressing issue of automatic generation control (AGC) within two area interconnected power system (TAIPS). The sub-objective functions include integral time absolute errors (ITAE) for frequency deviations and control errors in both areas, along with ITAE of fluctuation in tie-line power. These are integrated into an overall objective function, with ROC method systematically assigning weights to each sub-objective. Subsequently, a PID controller is designed based on this objective function. To further optimize objective function, Jaya optimization algorithm (JOA) is implemented, alongside other optimization algorithms such as teacher–learner based optimization algorithm (TLBOA), Luus–Jaakola algorithm (LJA), Nelder–Mead simplex algorithm (NMSA), elephant herding optimization algorithm (EHOA), and differential evolution algorithm (DEA). Six distinct case analyses are conducted to evaluate controller’s performance under various load conditions, plotting data to illustrate responses to frequency and tie-line exchange fluctuations. Additionally, statistical analysis is performed to provide further insights into efficacy of JOA-based PID controller. Furthermore, to prove the efficacy of JOA-based proposed controller through non-parametric test, Friedman rank test is utilized.
Use of Immune Profiling Panel to assess the immune response of septic patients for prediction of worsening as a composite endpoint
Authors: Peronnet Estelle , Terraz Gabriel , Cerrato Elisabeth , Imhoff Katia , Blein Sophie , Brengel-Pesce Karen , Bodinier Maxime , Fleurie Aurore , Rimmelé Thomas , Lukaszewicz Anne-Claire , Monneret Guillaume , Llitjos Jean-François
Published: May 2024

Sepsis induces intense, dynamic and heterogeneous host response modulations. Despite improvement of patient management, the risk of mortality and healthcare-associated infections remains high. Treatments to counterbalance immune response are under evaluation, but effective biomarkers are still lacking to perform patient stratification. The design of the present study was defined to alleviate the limitations of existing literature: we selected patients who survived the initial hyperinflammatory response and are still hospitalized at day 5–7 after ICU admission. Using the Immune Profiling Panel (IPP), a fully automated RT-qPCR multiplex prototype, we optimized a machine learning model combining the IPP gene expression levels for the identification of patients at high risk of worsening, a composite endpoint defined as death or secondary infection, within one week after sampling. This was done on 332 sepsis patients selected from two retrospective studies. The IPP model identified a high-risk group comprising 30% of patients, with a significant increased proportion of worsening events at day 28 compared to the low-risk group (49% vs. 28%, respectively). These preliminary results underline the potential clinical application of IPP for sepsis patient stratification in a personalized medicine perspective, that will be confirmed in a larger prospective multicenter study.
Decitabine cytotoxicity is promoted by dCMP deaminase DCTD and mitigated by SUMO-dependent E3 ligase TOPORS
Authors: Carnie Christopher J , Götz Maximilian J , Palma-Chaundler Chloe S , Weickert Pedro , Wanders Amy , Serrano-Benitez Almudena , Li Hao-Yi , Gupta Vipul , Awwad Samah W , Blum Christian J , Sczaniecka-Clift Matylda , Cordes Jacqueline , Zagnoli-Vieira Guido , D’Alessandro Giuseppina , Richards Sean L , Gueorguieva Nadia , Lam Simon , Beli Petra , Stingele Julian , Jackson Stephen P
Published: May 2024

The nucleoside analogue decitabine (or 5-aza-dC) is used to treat several haematological cancers. Upon its triphosphorylation and incorporation into DNA, 5-aza-dC induces covalent DNA methyltransferase 1 DNA–protein crosslinks (DNMT1-DPCs), leading to DNA hypomethylation. However, 5-aza-dC’s clinical outcomes vary, and relapse is common. Using genome-scale CRISPR/Cas9 screens, we map factors determining 5-aza-dC sensitivity. Unexpectedly, we find that loss of the dCMP deaminase DCTD causes 5-aza-dC resistance, suggesting that 5-aza-dUMP generation is cytotoxic. Combining results from a subsequent genetic screen in DCTD-deficient cells with the identification of the DNMT1-DPC-proximal proteome, we uncover the ubiquitin and SUMO1 E3 ligase, TOPORS, as a new DPC repair factor. TOPORS is recruited to SUMOylated DNMT1-DPCs and promotes their degradation. Our study suggests that 5-aza-dC-induced DPCs cause cytotoxicity when DPC repair is compromised, while cytotoxicity in wild-type cells arises from perturbed nucleotide metabolism, potentially laying the foundations for future identification of predictive biomarkers for decitabine treatment.
Amplifying the electrochemical footprint of <1000 molecules in a dissolving microdroplet
Authors: Nguyen James H. , Rana Ashutosh , Dick Jeffrey E.
Published: May 2024

We present an electrochemical platform for the detection and identification of <1000 molecules through an EC' mechanism. The EC' catalytic mechanism allows for a feedback loop mechanism which amplifies the electrochemical signal of Cp2*(Fe)II.
Investigating the mechanistic impact of pork soft tissue preparation techniques on the classification precision of laser-induced breakdown spectroscopy
Authors: Lin Jingjun , Li Yao , Ding Ke , Lin Xiaomei , Che Changjin
Published: May 2024

The mechanism of the effect of sample preparation methods on the signal was explored through an in-depth study of the plasma density and temperature.
Electrochemical quinuclidine-mediated Minisci-type acylation of N-heterocycles with aldehydes
Authors: Li Yongmei , Sun Liangbo , Huang Shengyang , Xu Kun , Zeng Cheng-Chu
Published: May 2024

The electro-generation of acyl radicals from both aromatic and aliphatic aldehydes is a synthetic challenge. We addressed this challenge by merging electro-oxidation and a quinuclidine-mediated HAT strategy.
Mechanochemical reduction of alkyl and aryl halides using mesoporous zinc oxide
Authors: Li Zhengheng , Zhang Longfei , Ding Ran , Wang Jian , Chen Du , Ren Ziye , Ding Chengqiang , Chen Kai , Wang Jialin , Wang Zhao
Published: May 2024

We proposed a mechanochemical approach to achieve efficient hydrodehalogenation of organic halides by using mesoporous ZnO as mechanoredox catalyst.
Synthesis of sterically congested double helicene by alkyne cycloisomerization
Authors: Hirano Junichiro , Miyoshi Sayaka , Yashima Eiji , Ikai Tomoyuki , Shinokubo Hiroshi , Fukui Norihito
Published: May 2024

Alkyne cycloisomerization of 2,7,10,15-tetra(ortho-alkynylphenyl)benzo[g,p]chrysene containing bulky 4-alkoxy-2,6-dimethylphenyl groups at the alkyne terminals selectively proceeded at the sterically crowded bay-region.
Demethylenative cyclization of 1,7-enynes using α-amino radicals as a traceless initiator enabled by Cu(i)-photosensitizers
Authors: Jiang Qinfang , Bao Hanyang , Peng Yun , Zhou Yan , Chen Lang , Liu Yunkui
Published: May 2024

A Cu(i)-photosensitizer-enabled demethylenative radical cyclization of 1,7-enynes to access quinoline-2-(1H)-ones was successfully achieved using α-amino radicals as a traceless radical initiator.
Selective ion migration in a polyelectrolyte driving a high-performance flexible moisture-electric generator
Authors: Han Yongxiang , Wang Yanlei , Wang Mi , Lv Zhaoyang , Zhang Ziqi , He Hongyan
Published: May 2024

A flexible moisture generator based on selective ion transport can generate a high voltage of 0.88 V from ambient humidity.
Exploring weak ligand–protein interactions by relaxometry of long-lived spin order
Authors: Kozinenko Vitaly P. , Kiryutin Alexey S. , Yurkovskaya Alexandra V.
Published: May 2024

Measuring relaxation as a function of the external magnetic field detects weak ligand–protein interactions. Employing long-lived spin order instead of longitudinal magnetization extends this method's capabilities.
Cytotoxic Staphylococcus aureus PSMα3 inhibits the aggregation of human insulin in vitro
Authors: Kalitnik Aleksandra , Szefczyk Monika , Wojciechowska Alicja W. , Wojciechowski Jakub W. , Gąsior-Głogowska Marlena , Olesiak-Bańska Joanna , Kotulska Małgorzata
Published: May 2024

An α-helical PSMα3 considerably inhibits the fibrillation of human insulin in vitro. The anti-amyloidogenic effect of PSMα3 is concentration-dependent. PSMα3 inhibits insulin aggregation through the suppression of primary nucleation.
High-temperature rotation–vibration spectrum of iminosilylene (HNSi)
Authors: Li Ximing , Qin Zhi , Liu Linhua
Published: May 2024

We present the first molecular line list for HNSi. This new line list covers the wavenumber range of 0–9000 cm−1 (wavelengths of λ ≥ 1.11 μm) and is suitable for temperatures up to T = 3000 K.
Transparent grating-based metamaterials for dynamic infrared radiative regulation smart windows
Authors: Wang Pan , Wang Haoyu , Sun Ya , Zhang Mengqi , Chen Shaowen , Xiao Chengyu , Zhou Han
Published: May 2024

We propose an ITO grating-based metamaterial for high visible transmittance and excellent infrared tunability (0.73 at 8–13 μm) as smart windows.
Tm3+ mediated multicolor luminescence of NaYbF4:Er,Tm@NaYF4 for advanced anti-counterfeiting
Authors: Li Jiaxin , Wang Pengli , Zhang Yujiao , Xiao Dan , Zhou Cuisong
Published: May 2024

NaYbF4:Er,Tm@NaYF4 UCNPs combine the advantages of Tm3+ mediated multicolor luminescence and excitation power dependent color change, showing great application potential in advanced anti-counterfeiting of paintings.
Synthesis and photoluminescence properties of high-quality reddish-orange emitting Ca4Nb2O9:Eu3+ phosphors for WLEDs and anti-counterfeiting
Authors: Xiang Weiwei , Yu Jae Su
Published: May 2024

The Ca4Nb2O9:Eu3+ phosphors were synthesized and their photoluminescence properties were investigated for white light-emitting diode and anti-counterfeiting applications.
Ruthenium nitrosyl complexes with NO release capability: the use of fluorene as an antenna
Authors: Mudrak Vladyslav , Lacroix Pascal G. , Tassé Marine , Mallet-Ladeira Sonia , Roshal Alexander , Malfant Isabelle
Published: May 2024

A fluorescent antenna is grafted to a ruthenium nitrosyl (Ru–NO) complex to collect photons for releasing nitric oxide (NO˙). A resulting encaging parameter is investigated experimentally by means of NO˙ release experiments.
Investigating the effect of fusion partners on the enzymatic activity and thermodynamic stability of poly(ethylene terephthalate) degrading enzymes
Authors: Oliveira Liliana , Cahill Alex , Wuscher Len , Green Kerry R. , Bemmer Victoria , Lichtenstein Bruce R.
Published: May 2024

We investigate the influence of the switchable thermal stability of a fusion partner on the activity of PETases demonstrating a range of optimal reaction temperatures.
The interplay of density functional selection and crystal structure for accurate NMR chemical shift predictions
Authors: Ramos Sebastian A. , Mueller Leonard J. , Beran Gregory J. O.
Published: May 2024

This study has investigated the impact improving the quality of molecular crystal geometries can have on the accuracy of predicted 13C and 15N chemical shifts in organic crystals.
Non-enzymatic signal-on electrochemiluminescence detection of organophosphorus pesticides based on tungsten disulfide quantum dots
Authors: Sun Yuzhu , Liu Wendong , Chen Mingyue , Ji Hongfei , Jiang Man , Hao Zhe , Li Xiyan , He Shuijian , Zhang Libing , Zhang Ruizhong
Published: May 2024

A sustainable non-enzymatic electrochemiluminescence sensing technology provides a novel approach for the identification and quantification of neurotoxic organophosphorus pesticides (OPs) from various pesticides, offering a “signal-on” mechanism.
Rapid and high-throughput synthesis of diverse MOFs with centrifuge tube grinding strategy
Authors: Wang Hao-Cheng , Liu Xiao , Ma Jian-Gong , Cheng Peng
Published: May 2024

A facile CTG synthesis strategy was developed for synthesing various MOFs and incorporating different functionalities into the MOF lattice in one step.
2D arrays of hollow carbon nanoboxes: outward contraction-induced hollowing mechanism in Fe–N–C catalysts
Authors: Song Xiaokai , Wang Xiaoke , Wei Jiamin , Zhou Shenghua , Wang Haifeng , Lou Jiali , Zhang Yaqi , Liu Yuhai , Zou Luyao , Zhao Yingji , Wei Xiaoqian , Osman Sameh M. , Li Xiaopeng , Yamauchi Yusuke
Published: May 2024

A structural and electronic dual-modulation is achieved on 2D arrays of hollow carbon nanoboxes, exhibiting exceptional performance in rechargeable zinc–air batteries.
Palladium-catalyzed asymmetric [4 + 3] cycloaddition of methylene-trimethylenemethane: access to seven-membered exocyclic axially chiral allenes
Authors: Wu Yafei , Wang Zhuo , Shan Yuqian , Ma Yukun , Li Teng , Yuan Chunhao , Guo Hongchao , Mao Biming
Published: May 2024

A palladium-catalyzed asymmetric [4 + 3] cycloaddition of the methylene-trimethylenemethane donor with an azadiene has been developed, affording benzofuro[3,2-b]azepine-derived exocyclic chiral allene with control of axial and point chirality.
Role of interaction range on the microstructure and dynamics of attractive colloidal systems
Authors: Mangal Deepak , Jamali Safa
Published: May 2024

With increase in attraction range, the final structure transitions from a single connected network to a fluid of dense clusters.
The role of the nucleus for cell mechanics: an elastic phase field approach
Authors: Chojowski Robert , Schwarz Ulrich S. , Ziebert Falko
Published: May 2024

We developed a phase field model for elastic cells with the nucleus modelled as an inclusion of higher stiffness and then studied cell adhesion with active contraction, cell deformation experiments and viscoelastic effects.
A Clinical Focus on Shared Decision Making in Clinical Practice When Providing Dysarthria and Dysphagia Services to Individuals With Amyotrophic Lateral Sclerosis
Authors: Donohue Cara , Perry Bridget , (Focht) Garand Kendrea L.
Published: May 2024

Purpose:

Traditional health care decision-making models center on clinicians making decisions for patients/caregivers based on the best available research evidence. However, this diminishes patient/caregiver involvement in their care and hinders the ability to align care plans with patient values and preferences. Shared decision making is a potentially beneficial process to implement with individuals with amyotrophic lateral sclerosis (ALS) to provide more holistic, patient-centered dysarthria and dysphagia treatment. Shared decision making promotes active involvement by patients/caregivers by informing them of potential treatment options, understanding their values and preferences, and aligning their desires with treatment options to determine the most optimal individualized care plan.

Conclusions:

The benefits and barriers to incorporating shared decision making within ALS multidisciplinary clinics are discussed in this clinical focus article. Furthermore, a fictional case study example of how to apply shared decision making to dysarthria and dysphagia management of individuals with ALS is provided.
Microstructure development of Ti scaffold by laser powder bed fusion with chemical polishing and its mechanical properties, biocompatibility
Authors: Lu Changfu , Chen Jing , Ma Teng , Chen Yuxin , Zeng Da , Gan Yiliang , Yang Youwen
Published: May 2024

Titanium (Ti) dental scaffolds are widely used in dental prosthetics due to their excellent mechanical properties and biocompatibility. However, conventional Ti scaffolds manufactured through machining often do not fit perfectly with the bone defect site. Laser powder bed fusion (LPBF) technology enables the personalised manufacturing of custom‐made Ti scaffolds. A custom‐made Ti scaffold was prepared using LPBF and its surface roughness was improved through chemical polishing. To enhance the surface roughness, a nitric acid mixed solution with a specific composition of HF: HNO3:C3H6O3 = 2:2:3 was used. The polishing mechanism was investigated by adjusting the F/Ti ratio to control the formation and dissolution of the oxide film. As a result, the surface of the Ti scaffold after polishing exhibited a smooth and flat appearance compared to the LPBF part, with a reduced surface roughness (Ra) of 1.23 ± 0.19 μm. The custom‐made Ti scaffold also demonstrated favourable mechanical properties, with a bending strength of 335.18 ± 33.62 MPa and stiffness of 2.13 ± 0.21 GPa. Furthermore, in vitro cell tests confirmed the excellent biocompatibility of the custom‐made Ti scaffold. The authors present a feasible strategy for the further clinical application of custom‐made Ti scaffolds, offering enhanced surface properties and addressing the limitations of conventional machining methods.
GRB 180128A: A second magnetar giant flare candidate from the Sculptor Galaxy
Authors: Trigg Aaron C. , Burns Eric , Roberts Oliver J. , Negro Michela , Svinkin Dmitry S. , Baring Matthew G. , Wadiasingh Zorawar , Christensen Nelson L. , Andreoni Igor , Briggs Michael S. , Di Lalla Niccolò , Frederiks Dmitry D. , Lipunov Vladimir M. , Omodei Nicola , Ridnaia Anna V. , Veres Peter , Lysenko Alexandra L.
Published: May 2024

Magnetars are slowly rotating neutron stars that possess the strongest magnetic fields known in the cosmos (1014 − 1015G). They display a range of transient high-energy electromagnetic activity. The brightest and most energetic of these events are the gamma-ray bursts (GRBs) known as magnetar giant flares (MGFs), with isotropic energiesEiso ≈ 1044 − 1046erg. Only seven MGF detections have been made to date: three unambiguous events occurred in our Galaxy and the Magellanic Clouds, and the other four MGF candidates are associated with nearby star-forming galaxies. As all seven identified MGFs are bright at Earth, additional weaker events likely remain unidentified in archival data. We conducted a search of theFermiGamma-ray Burst Monitor database for candidate extragalactic MGFs and, when possible, collected localization data from the Interplanetary Network (IPN) satellites. Our search yielded one convincing event, GRB 180128A. IPN localizes this burst within NGC 253, commonly known as the Sculptor Galaxy. The event is the second MGF in modern astronomy to be associated with this galaxy and the first time two bursts have been associated with a single galaxy outside our own. Here we detail the archival search criteria that uncovered this event and its spectral and temporal properties, which are consistent with expectations for a MGF. We also discuss the theoretical implications and finer burst structures resolved from various binning methods. Our analysis provides observational evidence of an eighth identified MGF.
Production and industrial use of “Green” hydrogen in the climatic conditions of Turkmenistan
Authors: Saryyev Vepa , Charyyev Yangibai , Akhmetova Irina
Published: May 2024

The scientific article discusses the importance of using “green” hydrogen in industry through a photovoltaic solar installation in the climatic conditions of Turkmenistan, and especially examines the possibilities and features of the use of “green” hydrogen in the production of ammonia, which is a widespread product in industry. To do this, it is based on the reaction of producing ammonia, and based on this, it is calculated that to produce 1 ton of ammonia, 177 kg of hydrogen is required. The water required for the electrolyzer operating in the 2G system is proposed to be provided from natural residues, and it is determined that the installation will be able to operate 10.65 hours a day. This in turn eliminates 970 kg of CO2 compared to the traditional method of burning natural gas to produce hydrogen. Calculations were carried out for the coordinates of the city of Mary.
Comparative chorological analysis of the avifauna of the forest-steppe mountains of Southern Siberia and Central Siberia in summer
Authors: Malkov Eugene
Published: May 2024

The article provides a chorological analysis of the avifauna of the forest-steppe using the example of the Khentei-Chikoy upland in the mountain region of Southern Siberia. In terms of comparison with the neighboring region of Central Siberia, a system of chorological approach is used, which has proven itself in the analysis of the avifauna of Northern Eurasia, including Central Siberia [1]. In the course of the analysis, the types of habitats and the zonal-landscape affiliation of the avifauna of the region of the mountains of Southern Siberia were determined in comparative terms with the avifauna of Central Siberia. General chorological characteristics are in many ways close to those of Central Siberia, but have their own differences and features.
Monitoring of atmospheric air pollution in the samarkand region under the influence of vehicles
Authors: Niyazova Oybakhor , Belyalova Lilya , Suyarov Sulton , Turdaliyev Mirjalol , Sayfiddinov Shakhzod
Published: May 2024

This article examines the influence of road transport on air pollution in the city of Samarkand, Republic of Uzbekistan. Based on the results of an analysis of the city map, five streets were identified with the largest number of vehicles. As part of the study, the volumes of emissions of harmful gases emitted by vehicles were measured, for this purpose 2 stationary and 2 mobile environmental control posts were used. Based on the results of measurements, it was revealed that road transport accounts for about 30.7 percent of the volume of emissions of pollutants into the air from all emissions in the city of Samarkand. Based on the results of the studies, appropriate conclusions were drawn and recommendations were made to reduce the impact of road transport on the city’s environment.
Aromatization patterns of hexane in high silicon zeolite
Authors: Rаhmatov Khudoyor , Fayzullaev Normurot , Buronov Firdavsiy , Matmuratov Shavkat , Takhirov Yuldash , Rifky Mohamed , Dissanayake Kasun , Samadiy Murodjon
Published: May 2024

In this article, methods of preparation of catalysts in analogues of in high-silica zeolite, conversion of n-hexane in the catalysts keeping in high-silica zeolite, of n-hexane to aromatic hydrocarbons, n-hexane to aromatic hydrocarbons in catalysts with high catalytic activity and selectivity modified with copper, 2%Cu*8%Zn/Н-High silica zeolite-40 conversion of n-hexane to aromatic hydrocarbons in the composition catalyst, activity in chain branching and aromatization processes to obtain high-octane components of fuels 2%Cu*8%Zn/Н-High silica zeolite-40 high silicon, A mesoporous aluminosilicate catalyst with high catalytic activity and selectivity was studied for the catalytic Aromatization of n-hexane to aromatic hydrocarbons. H-High silica zeolite-40 and 2%Cu*8 %Zn/H-High silica zeolite-40 catalysts with high catalytic activity and selectivity selected for catalytic Aromatization of n-hexane to aromatic hydrocarbons, Aromatization, chain branching and carbon-carbon by hydrogen action activity in the process of breaking the bond was studied.
Numerical solution of the problem of thermal effects on high-viscosity oil through a horizontal well
Authors: Gizzatullina Alina , Vafin Rif , Kuleshova Lyubov , Garifullina Gulnaz , Stepanova Razifa , Igoshin Roman , Potapova Ksenia
Published: May 2024

In this paper, the problem of developing a high-viscosity oil reservoir due to the effect of paragravity based on heating the reservoir section between the injection and production wells is considered. The thermal effect on the formation reduces the viscosity coefficient of the oil and increases the mobility of the raw material. The heat transfer equation is solved by the PSSS method. The task is solved in three stages. At the first stage, the oil reservoir is heated, at the second – its exposure, at the third - filtration.
Determination of the coefficient of hydraulic friction and factors reducing the value of hydraulic resistance along the length
Authors: Guseinova Elena , Mukhamadeev Eduard , Gilmanova Alfiya , Filimonov Oleg , Galiullina Irida
Published: May 2024

The article discusses issues related to the determination of hydraulic resistances and the coefficient of hydraulic friction based on scientific research conducted relatively recently. Formulas for determining the coefficient of hydraulic friction by various authors and studies on determining the value of hydraulic resistances are presented, which propose a non-traditional method for determining the average speed along the pipeline section. The works studying the influence of liquid temperature and the introduction of polymer additives on the amount of hydraulic losses are analyzed.
The use of nanoparticles to enhance oil recovery
Authors: Filimonov Oleg , Galiullina Irida , Gilmanova Alfiya , Mukhamadeev Eduard , Guseinova Elena
Published: May 2024

The article describes the actual problem of the introduction of nanotechnology in various fields of activity and existing technologies of the oil industry. The expediency of using nanotechnology to increase oil recovery, in the production of metal alloys to increase their strength characteristics and corrosion resistance, insulating coatings to reduce heat losses, lubricants that reduce wear of mating surfaces, in laboratory studies is shown. The results of the application of various nanotechnologies in the oil industry are presented.
Orbital angular momentum multiplexing architecture for OAM/SDM passive optical networks
Authors: Kadhim Ahmed C. , Al-Ithawi Sabah H. , Azzahrani Ahmad S.
Published: May 2024

Orbital Angular Momentum (OAM) multiplexing is a technology of communication systems that enables high-capacity optical communication networks. One of the most important determinants of this technology is the channel capacity, loss of power, and Bit Error Rate (BER) accompanying the transmission. This article proposed an Orbital Angular Momentum (OAM)/Spatial Domain Multiplexing (SDM) Gigabit-capable Passive Optical Network (G-PON) architecture for a Multiple-Input Multiple-Output (MIMO) communication system that supports (OAM/SDM G-PON) technology. The proposed architecture is used to multiplex the downstream OAM channels and the upstream SDM channels, and an OAM multiplexer/demultiplexer (OAM-MUX/DEMUX) is used to multiplex and demultiplex the OAM channels. In the OAM/SDM G-PON system, the signal will propagate through three different mediums, each having its own nature in influencing the power of the signal that passes through that medium. The experiment involves bidirectional transmissions with a DS/US data rate of 2.4 Gbps and Binary Phase Shift Keying (BPSK) downstream and 1.2 Gbps upstream. The observed results showed that the bit-error rate (BER) is a function of coupling angles and increases with the increase in the OAM ring size.
Towards a portable setup for the on-site SERS detection of miRNAs
Authors: Montesi Daniel , Bertone Sofia , Rivolo Paola , Geobaldo Francesco , Giorgis Fabrizio , Novara Chiara , Chiadò Alessandro
Published: May 2024

The actual implementation of on-site analysis of biomarkers, such as miRNAs, depends on the availability of portable and easy-to-handle detection systems that can be used as point-of-care in real life applications. In this work, an automatized microfluidic platform combined with a portable Raman spectrometer is reported and tested for miR-214 detection by surface enhanced Raman scattering (SERS). A multi-chamber SERS-active chip, functionalized according to a previously optimized two-step hybridization assay, was automatically incubated with the analyte solution. Preliminary tests allowed to adjust the portable Raman spectrometer acquisition conditions and to compare the obtained results with those of a bench Raman microscope. Finally, miR-214 at different concentrations was analyzed through an automatic procedure, achieving a limit of detection (LOD) in the picomolar range.
Le détaillage : altération des formes expressives chez la personne psychotique hallucinée
Authors: Ternoy Michel
Published: May 2024

Cet article se réfère aux résultats d’une recherche en prise directe avec la clinique psychopathologique dont le cadre d’investigation correspondait à l’exploration d’un thème bien déterminé : dégager et étudier dans la vision en images au Rorschach l’existence éventuelle de spécificités propres aux patients hallucinés pouvant nous informer sur la singularité de leur pathologie ; cette approche était élargie à l’étude d’autres formes d’expression. Il apparaît que le psychotique halluciné produit dans le Rorschach un mode de désagrégation de l’image perçue que j’ai nommée « détaillage » puisque c’est en allant vers la précision d’une partie de la réponse que se perd la représentation de l’ensemble auquel appartenait ce détail. Nous constatons que, mutatis mutandis, l’action de ce mécanisme s’impose dans le rêve éveillé dirigé, les dessins, les peintures et l’actualisation énonciative du langage.
Genotype-Dependent Response to Desmopressin in Hemophilia A and Proposal of a Predictive Response Score
Authors: Guillet Benoît , Pawlowski Maxime , Boisseau Pierre , Répessé Yohann , Beurrier Philippe , Bayart Sophie , Delavenne Xavier , Trossaërt Marc , Lenting Peter J.
Published: May 2024

Background Desmopressin (DDAVP) is used in patients with moderate/mild hemophilia A (PWMHs) to increase their factor VIII (FVIII) level and, if possible, normalize it. However, its effectiveness varies between individuals. The GIDEMHA study aims to investigate the influence of F8 gene variants.

Material and Methods The study collected the trajectory of FVIII levels from therapeutic intravenous DDAVP tests in four French hemophilia treatment centers. A pharmacological analysis was performed associated with efficacy scores according to F8 variants: absolute and relative responses, as well as new scores: absolute duration (based on duration with FVIII ≥ 0.50 IU.mL−1) and relative duration (based on half-life).

Results From enrolled 439 PWMHs, 327 had a hot-spot F8 variant (with ≥5 PWMHs). For these, the median (min–max) basal and peak FVIII were 0.20 (0.02–0.040) and 0.74 (0.14–2.18) IU.mL−1 respectively, with FVIII recovery being 3.80 IU.ml−1 (1.15–14.75). The median FVIII half-life was 3.9 hours (0.7–15.9 hours). FVIII was normalized (≥0.50 IU.mL−1) in 224/327 PWMHs (69%) and the median time with normalized FVIII was 3.9 hours (0.0–54.1 hours). Following the response profiles to DDAVP defined by the four efficacy scores, four groups of F8 variants were isolated, and then compared using survival curves with normalized FVIII (p < 0.0001): “long-lastingly effective” [p.(Glu739Lys), p.(Ser2030Asn), p.(Arg2178His), p.(Gln2208Glu), and T-stretch deletion in intron 13]; “moderately effective” [p.(Ser112Phe), p.(Ala219Thr), p.(Thr2105Ile), p.Phe2146Ser), and p.(Asp2150Asn)]; “moderately ineffective” [p.Ala81Asp), p.(Gln324Pro), p.(Tyr492His), p.(Arg612Cys), p.(Met701Val), p.(Val2035Asn), and p.(Arg2178Cys)]; and “frequently ineffective” [c.-219C > T, p.(Cys2040Tyr), p.(Tyr2169His), p.(Pro2319Leu), and p.(Arg2326Gln)].

Conclusion In view of our data, we propose indications for DDAVP use in PWMH based on F8 variants for minor and major invasive procedures.
Stereodivergent Synthesis of the Four Stereoisomers of Diethyl 4-Hydroxyphosphopipecolate from Ethyl (R)-4-Cyano-3-hydroxybutanoate
Authors: Ordoñez Mario , Morales-Solís Juan Carlos , Viveros-Ceballos José Luis
Published: May 2024

The stereodivergent synthesis of all four stereoisomers of diethyl 4-hydroxyphosphopipecolate from the commercial chiral building block ethyl (R)-4-cyano-3-hydroxybutanoate is described. Key steps in the synthesis of the target compounds involve the triethyl phosphite nucleophilic addition to chiral N-acyliminium ion easily obtained from (R)-4-hydroxypiperidin-2-one, giving diethyl (2R,4R)- and (2S,4R)-4-hydroxyphosphopipecolate diastereoisomers, easily separable by column chromatography followed by the 4-hydroxy epimerization through a sequential oxidation and highly diastereoselective reduction strategy, affording the diethyl (2R,4S)- and (2S,4S)-4-hydroxyphosphopipecolate, respectively, consistent with our recently found results. All synthesized compounds were thoroughly characterized.
A comparative study of emotional narratives in Chinese science fiction: exploring the gender perspective
Authors: Liu Yang
Published: May 2024

In recent years, there has been an increasing focus on women’s science fiction in China. A prevailing perception among readers and critics suggests that women’s sensibilities enable them to convey more nuanced emotions in their works. To examine this viewpoint within the realm of contemporary Chinese science fiction, a quantitative approach based on affective computing was employed. This approach allowed for a systematic evaluation of indicators such as emotional arc, emotional richness, and twistiness. The findings reveal that while individual writers may exhibit distinct emotional writing styles, overall, there is no significant disparity in emotional narratives between male and female science fiction writers.
Temperature dependences of thermal conductivity of solid heterogeneous crystalline and amorphous materials: An empirical approach to the description in the high-temperature region
Authors: Horbatenko Yu. V. , Sagan V. V. , Korolyuk O. A. , Romantsova O. O. , Krivchikov A. I.
Published: May 2024

This paper presents a detailed analysis of the thermal conductivity behaviors exhibited by a diverse array of nanostructured materials, ranging from multilayer graphene nanocomposites to semiconductor-based nanostructures such as Bi0.5Sb1.5Te3 and In0.53Ga0.47As composites. The investigation extends to superlattices, nanowires, and hybrid nanostructures, encompassing materials like hexagonal boron nitride flakes, iron oxide nanoporous films, and organic-inorganic hybrid materials. The thermal conductivity of these materials is characterized by distinct trends, with some showcasing crystal-like behavior and others demonstrating glass-like characteristics. The analysis employs empirical expressions to discern the contributions of phonons and diffusons in crystal-like materials and incorporates Peierls contributions and Arrhenius-type terms for glass-like behavior. Noteworthy observations include deviations in fitting certain materials at lower temperatures and the identification of negative diffuson contributions in specific cases. These findings contribute to a nuanced understanding of thermal transport in nanostructured materials and have implications for applications in advanced thermal management systems and thermoelectric devices. The extracted parameters provide valuable insights for researchers exploring the thermal conductivity of diverse nanostructured materials.
Low-temperature electrical conductivity of ion-beam irradiated Bi–Sb films
Authors: Andrino-Gómez A. , Moratalla M. , Redondo-Cubero A. , Gordillo N. , Ramos M. A.
Published: May 2024

Bismuth-antimony alloys are among the most studied topological insulators and also have very promising thermoelectric properties. In addition, in the amorphous state they exhibit superconductivity with critical temperatures in the range 6.0–6.4 K. In this work, we have prepared and studied different polycrystalline films of Bi100–xSbx (x = 0, 5, 10, 15), and we have induced, through ion beam irradiation, significant damage in their internal structure with the aim of amorphizing the material. Specifically, we have irradiated Bi ions in the 10–30 MeV range, exploiting the capabilities of a 5 MV ion beam accelerator of tandem type. We have characterized the Bi–Sb films before and after irradiation from a morphological and structural point of view and measured their electrical resistivity from room temperature to near 2 K, to evaluate the influence of the preparation method and degree of disorder. We have found that the studied Bi–Sb system always behaves as a small energy gap semiconductor that follows the empirical Meyer–Neldel rule, which correlates the conductivity prefactor with the exponential value of the energy gap.
Distribution of impurities in base-depleted region of diode temperature sensor
Authors: Bebitov R. R. , Abdulkhaev O. A. , Yodgorova D. M. , Istamov D. B. , Kuliyev Sh. M. , Khakimov A. A. , Bobonazarov A. B. , Rakhmatov A. Z.
Published: May 2024

The performance of diode temperature sensors depends on their base-depleted region thickness and impurity distribution profile. In this article, we study the boron diffusion process in the thin base region with a thickness of about 1 μm. We show that, for the proposed p+–n–p temperature sensor structure, the impurity distribution in the n region has the form of an asymmetric parabola, with an extreme concentration point shifted towards the “upper” p+ region.
Averaging principles for multiscale stochastic Cahn–Hilliard system
Authors: Gao Peng
Published: May 2024

In this paper, we will establish averaging principles for the multiscale stochastic Cahn–Hilliard system. The stochastic averaging principle is a powerful tool for studying qualitative analysis of stochastic dynamical systems with different time-scales. Under suitable conditions, two kinds of averaging principle (the autonomous case and the nonautonomous case) are proved, and as a consequence, the multiscale system can be reduced to a single stochastic Cahn–Hilliard equation (averaged equation) with a modified coefficient, the slow component of multiscale stochastic Cahn–Hilliard system towards to the solution of the averaged equation in moment (the autonomous case) and in probability (the nonautonomous case).
Eigenvalue ratios for Sturm–Liouville problems
Authors: Hedhly Jihed
Published: May 2024

In this paper, we prove the optimal lower bound λ2λ1≥4 of the Sturm-Liouville problem −(p(x)y′)′ + q(x)y = λρ(x)y, with Dirichlet boundary conditions for single-well potential q and single-barrier function pρ on [0,1]. In the case of symmetric coefficients, we establish the lower bound λnλ1≥n2 for single-well q and single-barrier function pρ with λ1 > 0 and μ1 ≤ 0, where μ1 is the first eigenvalue of the Neumann boundary problem. All the above estimates are given for q ≤ 0 without assumptions on the monotonicity of q.
Impurities in 4H silicon carbide: Site preference, lattice distortion, solubility, and charge transition levels
Authors: Huang Yuanchao , Wang Rong , Yang Deren , Pi Xiaodong
Published: May 2024

4H Silicon carbide (SiC) is widely recognized as one of the most advanced wide bandgap semiconductors used in the production of high-efficiency power electronic devices. Impurities play a crucial role in achieving the desired electrical properties in 4H-SiC, yet the understanding of impurities in this material remains limited. In this study, first-principles formation-energy calculations were employed to establish a comprehensive database of formation-energy diagrams for impurities in 4H-SiC. This database includes valuable information on site preference, lattice distortion, solubility, and charge transition levels (CTLs) of the impurities. The site preference for each impurity is closely related to factors such as the Fermi energy, chemical potential, and the impurity species itself. To assess the lattice distortion caused by each impurity, a comparison was made between the volume changes before and after doping. Moreover, the solubility of each impurity was determined using the detailed balance theory, thereby enabling a direct measure of the maximum impurity concentration achievable in the material. Based on the CTLs, the impurities in 4H-SiC were classified into four categories: n-type impurities, p-type impurities, amphoteric impurities, and non-electroactive impurities. This comprehensive property database for impurities in 4H-SiC provides valuable insights for tailoring the material properties through controlled doping, thereby ultimately leading to enhanced performance of power electronic devices.