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1.
BMC Plant Biol ; 24(1): 307, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644483

RESUMO

BACKGROUND: Luffa (Luffa spp.) is an economically important crop of the Cucurbitaceae family, commonly known as sponge gourd or vegetable gourd. It is an annual cross-pollinated crop primarily found in the subtropical and tropical regions of Asia, Australia, Africa, and the Americas. Luffa serves not only as a vegetable but also exhibits medicinal properties, including anti-inflammatory, antidiabetic, and anticancer effects. Moreover, the fiber derived from luffa finds extensive applications in various fields such as biotechnology and construction. However, luffa Fusarium wilt poses a severe threat to its production, and existing control methods have proven ineffective in terms of cost-effectiveness and environmental considerations. Therefore, there is an urgent need to develop luffa varieties resistant to Fusarium wilt. Single-plant GWAS (sp-GWAS) has been demonstrated as a promising tool for the rapid and efficient identification of quantitative trait loci (QTLs) associated with target traits, as well as closely linked molecular markers. RESULTS: In this study, a collection of 97 individuals from 73 luffa accessions including two major luffa species underwent single-plant GWAS to investigate luffa Fusarium wilt resistance. Utilizing the double digest restriction site associated DNA (ddRAD) method, a total of 8,919 high-quality single nucleotide polymorphisms (SNPs) were identified. The analysis revealed the potential for Fusarium wilt resistance in accessions from both luffa species. There are 6 QTLs identified from 3 traits, including the area under the disease progress curve (AUDPC), a putative disease-resistant QTL, was identified on the second chromosome of luffa. Within the region of linkage disequilibrium, a candidate gene homologous to LOC111009722, which encodes peroxidase 40 and is associated with disease resistance in Cucumis melo, was identified. Furthermore, to validate the applicability of the marker associated with resistance from sp-GWAS, an additional set of 21 individual luffa plants were tested, exhibiting 93.75% accuracy in detecting susceptible of luffa species L. aegyptiaca Mill. CONCLUSION: In summary, these findings give a hint of genome position that may contribute to luffa wild resistance to Fusarium and can be utilized in the future luffa wilt resistant breeding programs aimed at developing wilt-resistant varieties by using the susceptible-linked SNP marker.


Assuntos
Resistência à Doença , Fusarium , Estudo de Associação Genômica Ampla , Luffa , Doenças das Plantas , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Fusarium/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Resistência à Doença/genética , Luffa/genética , Luffa/microbiologia , Genoma de Planta , Marcadores Genéticos , Variação Genética
2.
Chemistry ; 30(31): e202400982, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38533890

RESUMO

Glucose holds significant importance in disease diagnosis as well as beverage quality monitoring. The high-efficiency electrochemical sensor plays a crucial role in the electrochemical conversion technology. Ni(OH)2 nanosheets are provided with high specific surface area and redox activity that are widely used in electrochemistry. Conductive metal-organic frameworks (cMOFs) perfectly combine the structural controllability of organic materials with the long-range ordering of inorganic materials that possess the characteristic of high electron mobility. Based on the above considerations, the combination of Ni(OH)2 and Ni-HHTP (HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) as an electrode modification material is designed to enhance electrochemical performance. In this work, to improve glucose detection, a sequence of Ni(OH)2@NiCo-HHTP and NiM-LDH@Ni-HHTP (M=Co2+, Mn2+, Cu2+, LDH=layered double hydroxide) are successfully synthesised by doping metals into Ni-HHTP and Ni(OH)2, respectively. As a result, NiCu-LDH@Ni-HHTP showed the best excellent glucose detection sensitivity.

3.
Langmuir ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332611

RESUMO

An asymmetric structure is an important strategy for designing highly conductive molecular wires for a gap-fixed molecular circuit. As the conductance enhancement in the current strategy is still limited to about 2 times, we inserted a methylene group as a spacer in a conjugated structure to modulate the structural symmetry. We found that the conductance drastically enhanced in the asymmetric molecular wire to 1.5 orders of magnitude as high as that in the symmetric molecular wire. First-principles quantum transport studies attributed the effective enhancement to the synchronization of improved energy alignment and nearly symmetric coupling between the frontier orbitals and the electrodes.

4.
Inorg Chem ; 63(28): 13093-13099, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38953699

RESUMO

Designing and synthesizing hollow frame structures with unique three-dimensional open structures in electrocatalysis remain a challenge. Etching is an effective method to synthesize metal-organic frameworks (MOFs) with a hollow structure and rich function. Herein, we report the design and synthesis of Hf-doped CoP hollow nanocubes by selective etching and ion exchange. Different from the traditional etching method, we used acid xylenol orange solution to etch typically the (211) crystal face of ZIF-67, obtaining the unique bell-like structure, named XO-ZIF-67. Subsequently, Hf-doped CoP hollow nanocubes were formed by Hf4+ doping and simple phosphating treatment. Electrochemical tests showed that the overpotential of the obtained catalyst is only 291 mV at the current density of 10 mA cm-2 when applied in catalyzing the oxygen evolution reaction (OER). Furthermore, the catalyst shows excellent stability when running in 1 M KOH solution for 25 h.

5.
Opt Lett ; 48(13): 3359-3362, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390130

RESUMO

We present a deep background-mismodeling-learned reconstruction framework for high-accuracy fluorescence diffuse optical tomography (FDOT). A learnable regularizer incorporating background mismodeling is formulated in the form of certain mathematical constraints. The regularizer is then learned to obtain the background mismodeling automatically using a physics-informed deep network implicitly. Here, a deep-unrolled FIST-Net for optimizing L1-FDOT is specially designed to obtain fewer learning parameters. Experiments show that the accuracy of FDOT is significantly improved via implicitly learning the background mismodeling, which proves the validity of the deep background-mismodeling-learned reconstruction. The proposed framework can also be used as a general method to improve a class of image modalities based on linear inverse problems with unknown background modeling errors.

6.
Opt Lett ; 48(2): 199-202, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638417

RESUMO

The imaging fidelity of mesoscopic fluorescence molecular tomography (MFMT) in reflective geometry suffers from spatial nonuniformity of measurement sensitivity and ill-posed reconstruction. In this study, we present a spatially adaptive split Bregman network (SSB-Net) to simultaneously overcome the spatial nonuniformity of measurement sensitivity and promote reconstruction sparsity. The SSB-Net is derived by unfolding the split Bregman algorithm. In each layer of the SSB-Net, residual block and 3D convolution neural networks (3D-CNNs) can adaptively learn spatially nonuniform error compensation, the spatially dependent proximal operator, and sparsity transformation. Simulations and experiments show that the proposed SSB-Net enables high-fidelity MFMT reconstruction of multifluorophores at different positions within a depth of a few millimeters. Our method paves the way for a practical reflection-mode diffuse optical imaging technique.


Assuntos
Tomografia Óptica , Tomografia Óptica/métodos , Algoritmos , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos , Tomografia , Imagens de Fantasmas
7.
Opt Lett ; 48(6): 1498-1501, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36946962

RESUMO

In this Letter, we demonstrate a high-sensitivity vector bend sensor based on a fiber directional coupler. The fiber directional coupler is composed of two parallel waveguides inscribed within a no-core fiber (NCF) by a femtosecond laser. Since the two written waveguides have closely matched refractive indices and geometries, the transmission spectrum of the fiber directional coupler possesses periodic resonant dips. Such a fiber directional coupler exhibits a good bending-dependent spectral shift response due to its asymmetric structure. Experimental results show that bending sensitivities of -97.11 nm/m-1 and 58.22 nm/m-1 are achieved for the 0° and 180° orientations in the curvature range of 0-0.62 m-1, respectively. In addition, the proposed fiber directional coupler is shown to be insensitive to external humidity changes, thus improving its suitability in high-accuracy bending measurements.

8.
Phys Rev Lett ; 131(7): 076701, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37656855

RESUMO

Using optical magnetospectroscopy, we investigate the magnetic excitations of Na_{2}Co_{2}TeO_{6} in a broad magnetic field range (0 T≤B≤17.5 T) at low temperature. Our measurements reveal rich spectra of in-plane magnetic excitations with a surprisingly large number of modes, even in the high-field spin-polarized state. Theoretical calculations find that the Na-occupation disorder in Na_{2}Co_{2}TeO_{6} plays a crucial role in generating these modes. Our Letter demonstrates the necessity to consider disorder in the spin environment in the search for Kitaev quantum spin liquid states in practicable materials.

9.
BMC Musculoskelet Disord ; 24(1): 112, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36765310

RESUMO

BACKGROUND: Although clavicle fractures are common injuries in adults, simultaneous bilateral clavicle fractures are rarely reported. The present report describes 13 patients with simultaneous bilateral traumatic clavicle fractures who were treated with surgical management and followed for more than 12 months postoperatively. METHODS: This retrospective chart review involved skeletally mature patients with traumatic clavicle injuries. Patients with bilateral clavicle fractures who were followed up for at least 12 months after surgery were included. Data regarding the patients' demographics, injury characteristics, fracture classification, comorbidities, concomitant injuries, and treatment strategies were collected. Each displaced fracture was managed with open reduction and internal fixation. Postoperative follow-up included radiographs for assessment of bone union; calculation of the Constant-Murley score for shoulder function; administration of the Disability of the Arm, Shoulder, and Hand questionnaire for upper limb function; determination of the visual analogue scale score for pain; and assessment of complications. RESULTS: From October 2013 to November 2021, 15 patients (10 men, 5 women) were diagnosed with bilateral clavicle fractures among 1542 patients with clavicle injuries (overall incidence of 1.0%). Of these 15 patients, this study included 13 patients (8 men, 5 women; mean age, 38.3 ± 15.3 years) who were followed up for more than 12 months postoperatively. Among the 13 patients, 10 (77.0%) had associated concomitant injuries, and 25 sides were fixed with internal plate fixation. After a follow-up period of 29.9 ± 28.5 months, all fractures achieved bone healing. Eleven patients attained excellent shoulder function on both sides and returned to their pre-injury daily activities, and the remaining two patients had unilateral shoulder dysfunction. No complications occurred. CONCLUSIONS: Bilateral clavicle fractures are extremely rare and associated with polytrauma. Open reduction and internal fixation is recommended for such patients, especially those with severe chest injuries, because osteosynthesis of the clavicle can improve respiratory function and reduce the duration of functional disability.


Assuntos
Fraturas Ósseas , Lesões do Ombro , Adulto , Masculino , Humanos , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Clavícula/diagnóstico por imagem , Clavícula/cirurgia , Clavícula/lesões , Estudos Retrospectivos , Incidência , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas , Placas Ósseas , Resultado do Tratamento , Consolidação da Fratura
10.
Angew Chem Int Ed Engl ; 62(18): e202302521, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36891989

RESUMO

Organic nitrates are broadly applied as pharmaceuticals (acting as efficient nitric oxide donor), energetic materials, building blocks in organic synthesis, etc. However, practical and direct methods to access organic nitrates efficiently are still rare, mainly due to the lack of powerful nitrooxylating reagents. Herein, we report bench-stable and highly reactive noncyclic hypervalent iodine nitrooxylating reagents, oxybis(aryl-λ3 -iodanediyl) dinitrates (OAIDNs, 2), which are prepared just by using aryliodine diacetate and HNO3 . The reagents are used to achieve a mild and operationally simple protocol to access diverse organic nitrates. By employing of 2, zinc-catalyzed regioselective nitrooxylation of cyclopropyl silyl ethers is realized efficiently to access the corresponding ß-nitrooxy ketones with high functional-group tolerance. Moreover, a series of direct and catalyst-free nitrooxylations of enolizable C-H bonds are carried out smoothly to afford the desired organic nitrates within minutes by just mixing the substrates with 2 in dichloromethane.

11.
Opt Lett ; 47(10): 2538-2541, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561395

RESUMO

In fluorescence diffuse optical tomography (fDOT), the quality of reconstruction is severely limited by mismodeling and ill-posedness of inverse problems. Although data-driven deep learning methods improve the quality of image reconstruction, the network architecture lacks interpretability and requires a lot of data for training. We propose an interpretable model-driven projected gradient descent network (MPGD-Net) to improve the quality of fDOT reconstruction using only a few training samples. MPGD-Net unfolds projected gradient descent into a novel deep network architecture that is naturally interpretable. Simulation and in vivo experiments show that MPGD-Net greatly improves the fDOT reconstruction quality with superior generalization ability.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Óptica , Algoritmos , Simulação por Computador , Processamento de Imagem Assistida por Computador/métodos , Tomografia Óptica/métodos
12.
Eur J Neurol ; 29(8): 2499-2504, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35441750

RESUMO

BACKGROUND AND PURPOSE: Central nervous system (CNS) B-cell lymphoma-mimicking demyelinating diseases creates a diagnostic dilemma. This study aimed to determine the specific magnetic resonance imaging (MRI) features of CNS B-cell lymphoma to facilitate the early identification of the disease. METHODS: We retrospectively reviewed the brain MRI of biopsy-confirmed CNS B-cell lymphoma patients. They were initially diagnosed with CNS demyelination, and these images were compared with those of actual patients with demyelinating diseases. RESULTS: A total of 20 patients with CNS B-cell lymphoma and 12 patients with demyelination were included in this study. Cohesive enhancement with satellite enhancing foci surrounded by prominent non-enhancing areas of oedema is the major contrast-enhancing pattern of lymphoma patients, accounting for 81% (13) of patients with primary diffuse large B-cell lymphoma (DLBCL). This imaging pattern revealed a sensitivity of 81% and a specificity of 75% for lymphoma in the differential diagnosis between primary DLBCL and demyelinating disease in our cohort. Among these lesions, most of the nodules were located deeply, which yielded a specificity of 100% and a sensitivity of 69% for primary DLBCL. Enhancement in a single pattern (mainly ring-like, patchy or punctate; 57%) and no enhancement (30%) were commonly observed in demyelinating lesions, distinct from primary DLBCL (p < 0.05). CONCLUSIONS: Lesions with cohesive enhancement and satellite foci on T1 contrast-enhanced imaging could be a specific hallmark of CNS B-cell lymphoma, suggesting the need to withdraw steroidal therapy and biopsy confirmation.


Assuntos
Neoplasias do Sistema Nervoso Central , Doenças Desmielinizantes , Linfoma de Células B , Linfoma , Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Neoplasias do Sistema Nervoso Central/patologia , Doenças Desmielinizantes/diagnóstico por imagem , Humanos , Linfoma/diagnóstico , Linfoma/patologia , Linfoma de Células B/diagnóstico por imagem , Linfoma de Células B/patologia , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
13.
Appl Opt ; 61(32): 9590-9594, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36606896

RESUMO

We report a scheme to measure the broadband frequency response of photodetectors (PDs) with the capacity of self-calibration. The optical carrier at f 0 is modulated through one modulator, and this modulator is driven by a microwave signal with a fixed frequency f 1 to produce the carrier-suppressed double sideband optical signals f 0-f 1 and f 0+f 1. The frequency interval of the optical signals is 2f 1. Subsequently, the two optical signals are sent to another modulator driven by a swept microwave signal f m. Two pairs of carrier-suppressed double sideband signals with a high signal-to-noise ratio are generated. The frequencies of these signals are f 0-f 1-f m,f 0-f 1+f m, f 0+f 1-f m, and f 0+f 1+f m. After the PD under test, the frequency response can be extracted from the amplitude of the microwave signals at 2f 1, 2f 1-2f m, and 2f 1+2f m. Two PDs in our laboratory are experimentally characterized from 0.1 to 40 GHz with a resolution of 100 MHz. Compared with the traditional vector network analyzer swept method, the proposed method extends the measurement range from f m(max) to 2f 1+2f m(max) and has the capacity of self-calibration to eliminate the influence caused by the modulator frequency response on the measurement results.

14.
BMC Musculoskelet Disord ; 23(1): 873, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127646

RESUMO

BACKGROUND: To evaluate the outcomes and efficacy of a new technique of autogenous iliac crest bone grafting combined with locking compression plate (LCP) vertical fixation for aseptic recalcitrant long bone nonunion. METHODS: From July 2010 to September 2020, 36 aseptic recalcitrant long bone nonunions were treated with a bone-forming channel technique and internal LCP fixation. All the patients had received one or more failed treatments. The injury mechanism, nonunion type and duration, and prior treatments were recorded pre-operation. The routine treatment process included nonunion area exposure, previous implant removal, sclerotic bone debridement, LCP fixation, bone-forming channel creation, and iliac bone grafting, and a second LCP fixation when required. At follow-up, X-ray images were obtained to assess bone healing and implant failure. Visual analog scale (VAS), fracture site stability, limb function, activity, muscle strength, limb length, and complications were recorded. RESULTS: A total of 34 patients (24 males and 10 females) were finally enrolled, with a mean age of 49.8 ± 12.3 years. At a mean follow-up of 35.6 ± 22.0 months, 32 patients displayed bone union, with a healing rate of 94.1% and mean union time of 6.8 ± 2.4 months. The VAS score was 0.7 ± 1 at the final follow-up. The functional results showed that 19 patients were excellent, 11 patients were good, 2 patients were poor, and 2 patients did not heal. CONCLUSION: Bone-forming channel technique combined with LCP vertical fixation is an excellent option to treat recalcitrant long bone nonunion. LEVEL OF EVIDENCE: Therapeutic Level IV.


Assuntos
Transplante Ósseo , Fraturas não Consolidadas , Adulto , Placas Ósseas/efeitos adversos , Transplante Ósseo/métodos , Feminino , Fixação Interna de Fraturas/efeitos adversos , Fraturas não Consolidadas/diagnóstico por imagem , Fraturas não Consolidadas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
15.
Opt Lett ; 46(7): 1558-1561, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793485

RESUMO

A high-sensitivity ethanol gas sensor based on two microfiber couplers and the Vernier effect is examined in this Letter using the unique variation rate conversion point characteristics. The output spectrum of the two couplers connected in parallel are superimposed to form a symmetrical envelope curve, showing high responsivity to variations in the external environment. Ethanol sensitivity was achieved by coating the waist region of the coupler with a mixture of Nile red and polymethyl methacrylate. When the concentration of ethanol gas changes, the envelope spectrum shifts. Experimental results show that a high responsivity of 160 pm/ppm can be obtained by tracing the reference peaks in the envelope curve and that the response and recovery times are on the order of seconds.

16.
Phys Rev Lett ; 127(18): 184301, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34767395

RESUMO

We investigate the sideband spectra of a driven nonlinear mode with its eigenfrequency being modulated at a low frequency (<1 kHz). This additional parametric modulation leads to prominent antiresonance line shapes in the sideband spectra, which can be controlled through the vibration state of the driven mode. We also establish a direct connection between the antiresonance frequency and the squeezing of thermal fluctuation in the system. Our Letter not only provides a simple and robust method for squeezing characterization, but also opens a new possibility toward sideband applications.

17.
Nano Lett ; 20(6): 4588-4593, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32402200

RESUMO

When surface states (SSs) form in topological insulators (TIs), they inherit the properties of bulk bands, including the electron-hole (e-h) asymmetry but with much more profound impacts. Here via combining magneto-infrared spectroscopy with theoretical analysis, we show that e-h asymmetry significantly modifies the SS electronic structures when interplaying with the quantum confinement effect. Compared with the case without e-h asymmetry, the SSs now bear not only a band asymmetry, such as that in the bulk, but also a shift of the Dirac point relative to the bulk bands and a reduction of the hybridization gap of up to 70%. Our results signify the importance of e-h asymmetry in the band engineering of TIs in the thin-film limit.

18.
Opt Lett ; 45(5): 1268-1271, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32108822

RESUMO

We demonstrate a novel, to the best of our knowledge, refractive index (RI) sensor based on the Vernier effect in dual-microfiber coupler (MFC) structures. The sensor sensitivity was studied both theoretically and experimentally. The numerical results show that by tracing the wavelength shifts of the envelope formed by the Vernier effect, the sensitivity can be improved by several times compared to that obtained for normal coupler-based sensors. In this Letter, two MFCs with a width and free spectral range (FSR) of $\sim{3.5}\;{\unicode{x00B5} \rm m}$∼3.5µm and 6 nm, respectively, were fabricated. Based on the sensitivity of 5820 nm/RIU for a single coupler, we experimentally achieved an ultra-high sensitivity of 126,540 nm/RIU using dual MFCs by the Vernier effect in the RI range of 1.3350 to 1.3455, which shows good agreement with numerical simulations. The proposed all-fiber RI sensor has the advantages of high sensitivity and low cost and can find applications in chemical and biological detection as well as electronic/magnetic field measurement.

19.
Appl Opt ; 59(7): 2077-2084, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32225730

RESUMO

A single-mode-multimode-single-mode (SMS) optical fiber-based displacement sensing system mounted on an Ilizarov transverse tibial bone transport device for microcirculation reconstruction is reported. Wide-range displacement is approximated as a uniform extension of a spring that is connected to an SMS optical fiber structure acting as the displacement sensor and allowing full displacement characterization. Transmission spectrum changes are measured, providing a displacement range of 24 mm with a sensitivity of $ - {55.42}\;{\rm pm/mm}$-55.42pm/mm and a resolution of 45.2 µm. The experimental results are characterized using a polynomial response curve for measuring the displacement due to transverse distraction of the Ilizarov device. The SMS fiber interrogation system is based on a macrobending fiber edge filter-based ratiometric measurement system. The use of SMS fibers together with the macrobending fiber-based interrogation system eliminates the influence of temperature on the displacement measurement. The implementation of the all-fiber sensing system of this investigation has uniquely facilitated a smart clinical device with a wide displacement range as well as operating in real-time monitoring when attached to the Ilizarov transverse tibial bone transport device. It also means that this fiber-optic sensing device can be made more cost-effective, simpler in construction, and more versatile while providing a high degree of measurement accuracy and resolution.


Assuntos
Transplante Ósseo/instrumentação , Técnica de Ilizarov/instrumentação , Fibras Ópticas , Tíbia/diagnóstico por imagem , Desenho de Equipamento/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Humanos , Luz , Modelos Teóricos , Temperatura
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