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1.
Proc Natl Acad Sci U S A ; 121(18): e2316474121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38652749

RESUMO

Multimessenger searches for binary neutron star (BNS) and neutron star-black hole (NSBH) mergers are currently one of the most exciting areas of astronomy. The search for joint electromagnetic and neutrino counterparts to gravitational wave (GW)s has resumed with ALIGO's, AdVirgo's and KAGRA's fourth observing run (O4). To support this effort, public semiautomated data products are sent in near real-time and include localization and source properties to guide complementary observations. In preparation for O4, we have conducted a study using a simulated population of compact binaries and a mock data challenge (MDC) in the form of a real-time replay to optimize and profile the software infrastructure and scientific deliverables. End-toend performance was tested, including data ingestion, running online search pipelines, performing annotations, and issuing alerts to the astrophysics community. We present an overview of the low-latency infrastructure and the performance of the data products that are now being released during O4 based on the MDC. We report the expected median latency for the preliminary alert of full bandwidth searches (29.5 s) and show consistency and accuracy of released data products using the MDC. We report the expected median latency for triggers from early warning searches (-3.1 s), which are new in O4 and target neutron star mergers during inspiral phase. This paper provides a performance overview for LIGO-Virgo-KAGRA (LVK) low-latency alert infrastructure and data products using theMDCand serves as a useful reference for the interpretation of O4 detections.

2.
Proc Natl Acad Sci U S A ; 120(18): e2215098120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094126

RESUMO

CRISPR-Cas systems are widespread adaptive antiviral systems used in prokaryotes. Some phages, in turn, although have small genomes can economize the use of genetic space to encode compact or incomplete CRISPR-Cas systems to inhibit the host and establish infection. Phage ICP1, infecting Vibrio cholerae, encodes a compact type I-F CRISPR-Cas system to suppress the antiphage mobile genetic element in the host genome. However, the mechanism by which this compact system recognizes the target DNA and executes interference remains elusive. Here, we present the electron cryo-microscopy (cryo-EM) structures of both apo- and DNA-bound ICP1 surveillance complexes (Aka Csy complex). Unlike most other type I surveillance complexes, the ICP1 Csy complex lacks the Cas11 subunit or a structurally homologous domain, which is crucial for dsDNA binding and Cas3 activation in other type I CRISPR-Cas systems. Structural and functional analyses revealed that the compact ICP1 Csy complex alone is inefficient in binding to dsDNA targets, presumably stalled at a partial R-loop conformation. The presence of Cas2/3 facilitates dsDNA binding and allows effective dsDNA target cleavage. Additionally, we found that Pseudomonas aeruginosa Cas2/3 efficiently cleaved the dsDNA target presented by the ICP1 Csy complex, but not vice versa. These findings suggest a unique mechanism for target dsDNA binding and cleavage by the compact phage-derived CRISPR-Cas system.


Assuntos
Bacteriófagos , Proteínas Associadas a CRISPR , Bacteriófagos/genética , Sistemas CRISPR-Cas , DNA , Proteínas Associadas a CRISPR/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(15): e2120913119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35324337

RESUMO

SignificanceThe coronavirus main protease (Mpro) is required for viral replication. Here, we obtained the extended conformation of the native monomer of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Mpro by trapping it with nanobodies and found that the catalytic domain and the helix domain dissociate, revealing allosteric targets. Another monomeric state is termed compact conformation and is similar to one protomer of the dimeric form. We designed a Nanoluc Binary Techonology (NanoBiT)-based high-throughput allosteric inhibitor assay based on structural conformational change. Our results provide insight into the maturation, dimerization, and catalysis of the coronavirus Mpro and pave a way to develop an anticoronaviral drug through targeting the maturation process to inhibit the autocleavage of Mpro.


Assuntos
Antivirais , COVID-19 , Proteases 3C de Coronavírus , Inibidores de Proteases , SARS-CoV-2 , Regulação Alostérica/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , COVID-19/enzimologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , Humanos , Luciferases , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Conformação Proteica , Multimerização Proteica
4.
Plant Mol Biol ; 114(3): 69, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842584

RESUMO

Petunias are renowned ornamental species widely cultivated as pot plants for their aesthetic appeal both indoors and outdoors. The preference for pot plants depends on their compact growth habit and abundant flowering. While genome editing has gained significant popularity in many crop plants in addressing growth and development and abiotic and biotic stress factors, relatively less emphasis has been placed on its application in ornamental plant species. Genome editing in ornamental plants opens up possibilities for enhancing their aesthetic qualities, offering innovative opportunities for manipulating plant architecture and visual appeal through precise genetic modifications. In this study, we aimed to optimize the procedure for an efficient genome editing system in petunia plants using the highly efficient multiplexed CRISPR/Cas9 system. Specifically, we targeted a total of six genes in Petunia which are associated with plant architecture traits, two paralogous of FLOWERING LOCUS T (PhFT) and four TERMINAL FLOWER-LIKE1 (PhTFL1) paralogous genes separately in two constructs. We successfully induced homogeneous and heterogeneous indels in the targeted genes through precise genome editing, resulting in significant phenotypic alterations in petunia. Notably, the plants harboring edited PhTFL1 and PhFT exhibited a conspicuously early flowering time in comparison to the wild-type counterparts. Furthermore, mutants with alterations in the PhTFL1 demonstrated shorter internodes than wild-type, likely by downregulating the gibberellic acid pathway genes PhGAI, creating a more compact and aesthetically appealing phenotype. This study represents the first successful endeavor to produce compact petunia plants with increased flower abundance through genome editing. Our approach holds immense promise to improve economically important potting plants like petunia and serve as a potential foundation for further improvements in similar ornamental plant species.


Assuntos
Sistemas CRISPR-Cas , Flores , Edição de Genes , Petunia , Proteínas de Plantas , Plantas Geneticamente Modificadas , Petunia/genética , Petunia/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Edição de Genes/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mutagênese , Regulação da Expressão Gênica de Plantas , Fenótipo
5.
Small ; 20(27): e2310736, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38282175

RESUMO

2D alloy-based anodes show promise in potassium-ion batteries (PIBs). Nevertheless, their low tap density and huge volume expansion cause insufficient volumetric capacity and cycling stability. Herein, a 3D highly dense encapsulated architecture of 2D-Bi nanosheets (HD-Bi@G) with conducive elastic networks and 3D compact encapsulation structure of 2D nano-sheets are developed. As expected, HD-Bi@G anode exhibits a considerable volumetric capacity of 1032.2 mAh cm-3, stable long-life span with 75% retention after 2000 cycles, superior rate capability of 271.0 mAh g-1 at 104 C, and high areal capacity of 7.94 mAh cm-2 (loading: 24.2 mg cm-2) in PIBs. The superior volumetric and areal performance mechanisms are revealed through systematic kinetic investigations, ex situ characterization techniques, and theorical calculation. The 3D high-conductivity elastic network with dense encapsulated 2D-Bi architecture effectively relieves the volume expansion and pulverization of Bi nanosheets, maintains internal 2D structure with fast kinetics, and overcome sluggish ionic/electronic diffusion obstacle of ultra-thick, dense electrodes. The uniquely encapsulated 2D-nanosheet structure greatly reduces K+ diffusion energy barrier and accelerates K+ diffusion kinetics. These findings validate a feasible approach to fabricate 3D dense encapsulated architectures of 2D-alloy nanosheets with conductive elastic networks, enabling the design of ultra-thick, dense electrodes for high-volumetric-energy-density energy storage.

6.
Plant Biotechnol J ; 22(6): 1724-1739, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38261466

RESUMO

Increased planting densities boost crop yields. A compact plant architecture facilitates dense planting. However, the mechanisms regulating compact plant architecture in cucurbits remain unclear. In this study, we identified a cucumber (Cucumis sativus) compact plant architecture (cpa1) mutant from an ethyl methane sulfonate (EMS)-mutagenized library that exhibited distinctive phenotypic traits, including reduced leaf petiole angle and leaf size. The candidate mutation causes a premature stop codon in CsaV3_1G036420, which shares similarity to Arabidopsis HOOKLESS 1 (HLS1) encoding putative histone N-acetyltransferase (HAT) protein and was named CsHLS1. Consistent with the mutant phenotype, CsHLS1 was predominantly expressed in leaf petiole bases and leaves. Constitutive overexpressing CsHLS1 in cpa1 restored the wild-type plant architecture. Knockout of CsHLS1 resulted in reduces leaf petiole angle and leaf size and as well as decreased acetylation levels. Furthermore, CsHLS1 directly interacted with CsSCL28 and negatively regulated compact plant architecture in cucumber. Importantly, CsHLS1 knockout increased the photosynthesis rate and leaf nitrogen in cucumbers, thereby maintaining cucumber yield at normal density. Overall, our research provides valuable genetic breeding resource and gene target for creating a compact plant architecture for dense cucumber planting.


Assuntos
Cucumis sativus , Folhas de Planta , Proteínas de Plantas , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/anatomia & histologia , Cucumis sativus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas , Fotossíntese/genética , Mutação , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo
7.
Magn Reson Med ; 92(1): 430-439, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38411265

RESUMO

PURPOSE: Electron spin resonance (ESR) is used to measure oxygen partial pressure (pO2) in biological media with many clinical applications. Traditional clinical ESR involves large magnets that encompass the subject of measurement. However, certain applications might benefit from a scanner operating within local static magnetic fields. Our group recently developed such a compact scanner for transcutaneous (surface) pO2 measurements of skin tissue. Here we extend this capability to subsurface (subcutaneous) pO2 measurements and verify it using an artificial tissue emulating (ATE) phantom. METHODS: We introduce a new scanner, tailored for subcutaneous measurements up to 2 mm beneath the skin's surface. This scanner captures pulsed ESR signals from embedded approximate 1-mm oxygen-sensing solid paramagnetic implant, OxyChip. The scanner features a static magnetic field source, producing a uniform region outside its surface, and a compact microwave resonator, for exciting and receiving ESR signals. RESULTS: ESR readings derived from an OxyChip, positioned approximately 1.5 mm from the scanner's surface, embedded in ATE phantom, exhibited a linear relation of 1/T2 versus pO2 for pO2 levels at 0, 7.6, 30, and 160 mmHg, with relative reading accuracy of about 10%. CONCLUSION: The compact ESR scanner can report pO2 data in ATE phantom from an external position relative to the scanner. Implementing this scanner in preclinical and clinical applications for subcutaneous pO2 measurements is a feasible next phase for this development. This innovative design also has the potential to operate in conjunction with artificial skin graft for wound healing, combining therapeutic and pO2 diagnostic features.


Assuntos
Oximetria , Oxigênio , Imagens de Fantasmas , Espectroscopia de Ressonância de Spin Eletrônica , Oximetria/métodos , Humanos , Desenho de Equipamento , Pele/diagnóstico por imagem
8.
New Phytol ; 241(1): 24-27, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37924218

RESUMO

C-terminally encoded peptides (CEP) signaling peptides are drivers of systemic pathways regulating nitrogen (N) acquisition in different plants, from Arabidopsis to legumes, depending on mineral N availability (e.g. nitrate) and on the whole plant N demand. Recent studies in the Medicago truncatula model legume revealed how root-produced CEP peptides control the root competence for endosymbiosis with N fixing rhizobia soil bacteria through the activity of the Compact Root Architecture 2 (CRA2) CEP receptor in shoots. Among CEP genes, MtCEP7 was shown to be tightly linked to nodulation, and the dynamic temporal regulation of its expression reflects the plant ability to maintain a different symbiotic root competence window depending on the symbiotic efficiency of the rhizobium strain, as well as to reinitiate a new window of root competence for nodulation.


Assuntos
Medicago truncatula , Rhizobium , Nódulos Radiculares de Plantas/microbiologia , Nodulação/genética , Simbiose/fisiologia , Raízes de Plantas/metabolismo , Sinais Direcionadores de Proteínas , Rhizobium/fisiologia , Medicago truncatula/microbiologia , Peptídeos/metabolismo , Fixação de Nitrogênio , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
Int J Legal Med ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39134883

RESUMO

The PowerPlex® 35GY System (Promega, USA) is an advanced eight-dye multiplex STR kit, incorporating twenty-three autosomal STR loci, eleven Y chromosome STR loci, one sex determining marker Amelogenin, and two quality indicators. This multiplex system includes 20 CODIS loci and up to 15 mini-STR loci with sizing values less than 250 bases. In this study, validation for PowerPlex® 35GY System was conducted following the guidelines of SWGDAM, encompassing sensitivity, precision, accuracy, concordance, species specificity, stutter, mixture, stability, and degraded DNA. The results from experiments demonstrated that the PowerPlex® 35GY System could effectively amplify DNA samples, with complete allele detection achieved at 125 pg. Moreover, over 90% of alleles from minor contributors were detected at a mixed ratio of 1:4. Additionally, the system was found to yield full profiles even in the presence of hematin, humic acid, and indigo. The PowerPlex® 35GY System demonstrated superior performance in the sensitivity and degraded DNA studies compared to a six-dye STR kit. Hence, it is evident that the PowerPlex® 35GY System is well-suited for forensic practice, whether in casework or for database samples. These findings provide strong support for the efficacy and reliability of the PowerPlex® 35GY System in forensic applications.

10.
Macromol Rapid Commun ; 45(1): e2300271, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37400426

RESUMO

A poly (3,6-bis(thiophen-2-yl)-2,5-bis(2-decyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione-co-(2,3-bis(phenyl)acrylonitrile)) (PDPADPP) copolymer, composed of diketopyrrolopyrrole (DPP) and a cyano (nitrile) group with a vinylene spacer linking two benzene rings, is synthesized via a palladium-catalyzed Suzuki coupling reaction. The electrical performance of PDPADPP in organic field-effect transistors (OFETs) and circuits is investigated. The OFETs based on PDPADPP exhibit typical ambipolar transport characteristics, with the as-cast OFETs demonstrating low field-effect hole and electron mobility values of 0.016 and 0.004 cm2  V-1  s-1 , respectively. However, after thermal annealing at 240 °C, the OFETs exhibit improved transport characteristics with highly balanced ambipolar transport, showing average hole and electron mobility values of 0.065 and 0.116 cm2  V-1  s-1 , respectively. To verify the application of the PDPADPP OFETs in high-voltage logic circuits, compact modeling using the industry-standard small-signal Berkeley short-channel IGFET model (BSIM) is performed, and the logic application characteristics are evaluated. The circuit simulation results demonstrate excellent logic application performance of the PDPADPP-based ambipolar transistor and illustrate that the device annealed at 240 °C exhibits ideal circuit characteristics.


Assuntos
Acrilonitrila , Simulação por Computador , Eletricidade , Elétrons , Nitrilas , Polímeros
11.
Qual Life Res ; 33(5): 1359-1371, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38401014

RESUMO

PURPOSE: The Comprehensive assessment of Acceptance and Commitment Therapy (CompACT) is a 23-item questionnaire measuring psychological flexibility, a quality of life protective factor. An 18-item version was recently produced. We assessed validity and reliability of CompACT, and equivalence of paper and electronic (eCompACT) versions in people with multiple sclerosis (PwMS) in Italy, Germany and Spain. METHODS: We used confirmatory factor analysis and assessed CompACT-23 and CompACT-18 measurement invariance between the three language versions. We assessed construct validity (Spearman's correlations) and internal consistency (Cronbach's alpha). Test-retest reliability (intraclass correlation coefficient, ICC) and equivalence of paper and eCompACT (ICC and linear regression model for repeated measures) were assessed in subsamples of PwMS. RESULTS: A total of 725 PwMS completed the study. The three-factor structure of the CompACT-23 showed poor fit (RMSEA 0.07; CFI 0.82; SRMR 0.08), while the fit of the CompACT-18 was good (RMSEA 0.05; CFI 0.93; SRMR 0.05). Configural and partial metric invariance were confirmed, as well as partial scalar invariance (reached when five items were allowed to vary freely). The CompACT-18 showed good internal consistency (all alpha ≥ 0.78); and test-retest reliability (all ICCs ≥ 0.86). Equivalence between paper and eCompACT was excellent (all ICCs ≥ 0.86), with no mode, order, or interaction effects. CONCLUSION: Results support using the refined CompACT-18 as a three-factor measure of psychological flexibility in PwMS. Paper and eCompACT-18 versions are equivalent. CompACT-18 can be used cross-culturally, but sub-optimal scalar invariance suggests that direct comparison between the three language versions should be interpreted with caution.


Assuntos
Terapia de Aceitação e Compromisso , Comparação Transcultural , Esclerose Múltipla , Psicometria , Humanos , Esclerose Múltipla/psicologia , Esclerose Múltipla/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Adulto , Análise Fatorial , Qualidade de Vida/psicologia , Alemanha , Espanha , Itália , Idoso
12.
Mol Ther ; 31(4): 1177-1187, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36733251

RESUMO

CjCas9 is one of the smallest CRISPR-associated (Cas9) nucleases for mammalian genome editing. However, it requires a long N4RYAC (R = A or G; Y = C or T) protospacer-adjacent motif (PAM), limiting its DNA targeting scope. In this study, we investigated the PAMs of three CjCas9 orthologs, including Hsp1Cas9, Hsp2Cas9, and CcuCas9, by performing a GFP-activation assay. Interestingly, Hsp1Cas9 and CcuCas9 recognized unique N4RAA and N4CNA PAMs, respectively. We further generated an Hsp1Cas9-Hsp2Cas9 chimeric Cas9 (Hsp1-Hsp2Cas9), which recognized a simple N4CY PAM. Genome-wide off-target analysis revealed that Hsp1-Hsp2Cas9 has very few off-targets compared to SpCas9. By analyzing the crystal structure of CjCas9, we identified eight mutations that can improve the specificity and generate a high-fidelity Hsp1-Hsp2Cas9-Y. Hsp1-Hsp2Cas9-Y enables the knockout of B4GALNT2 and CMAH in porcine fetal fibroblasts (PFFs). Moreover, we developed a high-fidelity Hsp1-Hsp2Cas9-KY which displayed undetectable off-targets revealed by GUIDE-seq at four tested loci. These natural and engineered Cas9 nucleases enabled efficient genome editing in multiple mammalian cells, expanding the DNA targeting scope.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Suínos , Mutação , DNA/genética , Genoma , Mamíferos
13.
Magn Reson Chem ; 62(5): 328-336, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37736944

RESUMO

Omega-3 fatty acid supplements, such as fish oil and plant-based oils, have gained popularity because of their potential health benefits. However, the quality and composition of these supplements can vary widely, particularly in terms of the two main forms of omega-3 fatty acids: triacylglycerols (TAGs) and ethyl esters (EEs). TAGs are the natural form found in fish oil but are prone to oxidation, whereas EEs are more stable but less well absorbed by the body. Differentiating between these forms is crucial for assessing the efficacy and tolerance of omega-3 supplements. This article describes a novel approach to differentiate between TAG and EE forms of omega-3 fatty acids in dietary supplements, utilizing a 60-MHz benchtop nuclear magnetic resonance (NMR) spectrometer. The proposed method using 1H and 1H-1H COSY NMR provides a quick and accurate approach to screen the forms of omega-3 fatty acids and evaluate their ratios. The presence of diacylglycerol (DAGs) in some supplements was also highlighted by this method and adds some information about the process used (i.e., esterification/enrichment). The affordability and user-friendliness of benchtop NMR equipment make this method feasible for food processing companies or quality control laboratories. In this study, 24 oil supplements were analyzed using NMR analysis in order to demonstrate the potential of this method for the differentiation of TAG and EE forms in omega-3 supplements.


Assuntos
Ácidos Graxos Ômega-3 , Ácidos Graxos , Ácidos Graxos Ômega-3/química , Óleos de Peixe/química , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética
14.
Magn Reson Chem ; 62(5): 378-385, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37994198

RESUMO

Efficient and robust analytical methods are needed to improve the identification and subsequent regulation of new psychoactive substances (NPS). NMR spectroscopy is a unique method able to determine the structure of small molecules such as NPS even in mixtures. However, high-field NMR analysis is associated with expensive purchase and maintenance costs. For more than a decade, compact NMR spectrometers have changed this paradigm. It was recently shown that a dedicated analytical workflow combining compact NMR and databases could identify the molecular structure of NPS, in spite of the lower spectral dispersion and sensitivity of compact spectrometers. This approach relies on 1H-13C HSQC to both recognize NPS and elucidate the structure of unknown substances. Still, its performance is limited by the need to compromise between resolution and experiment time. Here, we show that this strategy can be significantly improved by implementing non-uniform sampling (NUS) to improve spectral resolution in the 13C dimension of HSQC at no cost in terms of experiment time. Gains in the range of 3 to 4 in resolution are achieved for pure NPS and for a mixture. Finally, 2D HSQC with NUS was applied to improve the identification of NPS with the assistance of databases. The resulting method appears as a useful tool for the characterization of NPS in mixtures, which is essential for forensic laboratories.


Assuntos
Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos
15.
Magn Reson Chem ; 62(4): 236-251, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37311710

RESUMO

This article uses a variety of graphical and mathematical approaches to analyse 600- and 60-MHz ('benchtop') proton NMR spectra acquired from lipophilic and hydrophilic extracts of roasted coffee beans. The collection of 40 authenticated samples comprised various coffee species, cultivars and hybrids. The spectral datasets were analysed by a combination of metabolomics approaches, cross-correlation and whole spectrum methods, assisted by visualisation and mathematical techniques not conventionally employed to treat NMR data. A large amount of information content was shared between the 600-MHz and benchtop datasets, including in its magnitude spectral form, suggesting the potential for a lower cost, lower tech route to conducting informative metabolomics studies.


Assuntos
Imageamento por Ressonância Magnética , Prótons , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Alimentos
16.
Sensors (Basel) ; 24(14)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39066106

RESUMO

High-resolution spectroscopy employing spatial heterodyne spectrographs (SHS) holds significant promise for forthcoming space missions, building upon its established track record in science applications. Notably, it offers exceptional performance and cost- effectiveness in the ultraviolet-visual (UV-Vis) region compared to contemporary instruments. SHS instruments provide high-resolution capabilities and substantially larger etendues than similar resolving power instruments. This study introduces a comprehensive Python-based SHS model integrated with a user-friendly web scraping interface for target star selection, parameter generation, and 2D interferogram creation. Our SHS model demonstrates double the resolving power of a grating spectrometer and a throughput comparable to a Fourier transform spectrometer (FTS) but without moving parts, enhancing robustness for deployment in space. The interferogram processing algorithm includes flat-fielding, bias removal, apodization, and an inverse Fourier transform (IFT) for accurate spectrum retrieval. Despite bandwidth limitations due to resolving power constraints, SHS models excel in applications requiring high spectral resolution over narrow wavelength ranges, such as studying isotopic emission lines. The model provides optimization results and trade-offs for system parameters, ensuring precise spectral recovery with realistic signal-to-noise ratio (SNR) values. SHS is versatile and effective for various scientific applications, including investigating atomic and molecular emissions from comets, planetary atmospheres, the Earth's atmosphere, the Sun, and the interstellar medium (ISM). This research significantly contributes to expediting the development and deployment of SHS instruments, demonstrating their potential across numerous scientific domains.

17.
Sensors (Basel) ; 24(12)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38931619

RESUMO

In this paper, two kinds of miniaturization methods for designing a compact wideband tapered slot antenna (TSA) using either fan-shaped structures only or fan-shaped and stepped structures were proposed. First, a miniaturization method appending the fan-shaped structures, such as quarter circular slots (QCSs), half circular slots (HCSs), and half circular patches (HCPs), to the sides of the ground conductor for the TSA was investigated. The effects of appending the QCSs, HCSs, and HCPs sequentially on the input reflection coefficient and gain characteristics of the TSA were compared. The compact wideband TSA using the first miniaturization method showed the simulated frequency band for a voltage standing wave ratio (VSWR) less than 2 of 2.530-13.379 GHz (136.4%) with gain in the band ranging 3.1-6.9 dBi. Impedance bandwidth was increased by 29.7% and antenna size was reduced by 39.1%, compared to the conventional TSA. Second, the fan-shaped structures combined with the stepped structures (SSs) were added to the sides of the ground conductor to further miniaturize the TSA. The fan-shaped structures based on the HCSs and HCPs were appended to the ground conductor with the QCSs and SSs. The compact wideband TSA using the second miniaturization method had the simulated frequency band for a VSWR less than 2 of 2.313-13.805 GHz (142.6%) with gain in the band ranging 3.0-8.1 dBi. Impedance bandwidth was increased by 37.8% and antenna size was reduced by 45.9%, compared to the conventional TSA. Therefore, the increase in impedance bandwidth and the size reduction effect of the compact wideband TSA using the second miniaturization method were better compared to those using the first method. In addition, sidelobe levels at high frequencies decreased while gain at high frequencies increased. A prototype of the compact wideband TSA using the second miniaturization method was fabricated on an RF-35 substrate to validate the simulation results. The measured frequency band for a VSWR less than 2 was 2.320-13.745 GHz (142.2%) with measured gain ranging 3.1-7.9 dBi.

18.
J Environ Manage ; 361: 121276, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38820785

RESUMO

Urban dynamics and anthropogenic interventions led to an increase in noise pollution levels, with relevant implications for worldwide healthcare. Structures created to lessen noise pollution from traffic, industry, or other sources are known as noise, sound, or acoustic barriers. The research paper presents a unique design and development of noise barrier with newly composite mix of acoustic panels and vegetative cover augmenting noise attenuation and aesthetics. The barrier provides a symmetrical design around the vertical axis, hence assures utilization of both faces of the barrier. Additionally, the barrier hosts multiple slots to accommodate multi-material acoustic panels based on diverse noise frequencies and environmental conditions. The barrier integrates movable noise caps at 45°, 90°, 180°, and 270° angles for further attenuation and diversion of noise. A drip irrigation system within the soil box ensures optimal plant growth and stability to barrier. Experimental studies showcase the barrier's performance and its effectiveness in diverse noise scenarios. This innovative development provides a comprehensive solution towards noise mitigation through compact, customizable and sustainable green noise barrier.


Assuntos
Acústica , Ruído
19.
Molecules ; 29(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38731577

RESUMO

Recently, benchtop nuclear magnetic resonance (NMR) spectrometers utilizing permanent magnets have emerged as versatile tools with applications across various fields, including food and pharmaceuticals. Their efficacy is further enhanced when coupled with chemometric methods. This study presents an innovative approach to leveraging a compact benchtop NMR spectrometer coupled with chemometrics for screening honey-based food supplements adulterated with active pharmaceutical ingredients. Initially, fifty samples seized by French customs were analyzed using a 60 MHz benchtop spectrometer. The investigation unveiled the presence of tadalafil in 37 samples, sildenafil in 5 samples, and a combination of flibanserin with tadalafil in 1 sample. After conducting comprehensive qualitative and quantitative characterization of the samples, we propose a chemometric workflow to provide an efficient screening of honey samples using the NMR dataset. This pipeline, utilizing partial least squares discriminant analysis (PLS-DA) models, enables the classification of samples as either adulterated or non-adulterated, as well as the identification of the presence of tadalafil or sildenafil. Additionally, PLS regression models are employed to predict the quantitative content of these adulterants. Through blind analysis, this workflow allows for the detection and quantification of adulterants in these honey supplements.


Assuntos
Suplementos Nutricionais , Mel , Espectroscopia de Ressonância Magnética , Mel/análise , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética/métodos , Citrato de Sildenafila/análise , Fluxo de Trabalho , Quimiometria/métodos , Tadalafila/análise , Análise dos Mínimos Quadrados , Contaminação de Medicamentos/prevenção & controle , Análise Discriminante
20.
Nurs Outlook ; 72(1): 102003, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37479636

RESUMO

This panel paper is the third installment in a six-part Nursing Outlook special edition based on the 2022 Emory Business Case for Nursing Summit. The 2022 summit was led by Emory School of Nursing in partnership with Emory School of Business. It convened national nursing, health care, and business leaders to explore possible solutions to nursing workforce crises, including the nursing shortage. Each of the summit's four panels authored a paper in this special edition on their respective topic(s). This panel paper focuses on strategies to optimally distribute nursing talent in rural and underserved areas. It discusses the role of nursing talent distribution in ensuring equity in access to care for U.S. populations. Topics covered include the need for expanded and standardized advanced practice registered nurse (APRN) scope of practice, an expanded nurse licensure compact, reimbursement reforms, and competitive nursing salaries.


Assuntos
Prática Avançada de Enfermagem , Recursos Humanos de Enfermagem , Estados Unidos , Humanos , Licenciamento
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