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1.
EMBO Rep ; 25(2): 770-795, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182816

RESUMO

DExD/H-box helicases are crucial regulators of RNA metabolism and antiviral innate immune responses; however, their role in bacteria-induced inflammation remains unclear. Here, we report that DDX5 interacts with METTL3 and METTL14 to form an m6A writing complex, which adds N6-methyladenosine to transcripts of toll-like receptor (TLR) 2 and TLR4, promoting their decay via YTHDF2-mediated RNA degradation, resulting in reduced expression of TLR2/4. Upon bacterial infection, DDX5 is recruited to Hrd1 at the endoplasmic reticulum in an MyD88-dependent manner and is degraded by the ubiquitin-proteasome pathway. This process disrupts the DDX5 m6A writing complex and halts m6A modification as well as degradation of TLR2/4 mRNAs, thereby promoting the expression of TLR2 and TLR4 and downstream NF-κB activation. The role of DDX5 in regulating inflammation is also validated in vivo, as DDX5- and METTL3-KO mice exhibit enhanced expression of inflammatory cytokines. Our findings show that DDX5 acts as a molecular switch to regulate inflammation during bacterial infection and shed light on mechanisms of quiescent inflammation during homeostasis.


Assuntos
Adenina , Infecções Bacterianas , Receptor 2 Toll-Like , Animais , Camundongos , Adenina/análogos & derivados , Inflamação/genética , Metiltransferases/genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética
2.
Sensors (Basel) ; 24(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38400490

RESUMO

This paper presents an FPGA-based lightweight and real-time infrared image processor based on a series of hardware-oriented lightweight algorithms. The two-point correction algorithm based on blackbody radiation is introduced to calibrate the non-uniformity of the sensor. With precomputed gain and offset matrices, the design can achieve real-time non-uniformity correction with a resolution of 640×480. The blind pixel detection algorithm employs the first-level approximation to simplify multiple iterative computations. The blind pixel compensation algorithm in our design is constructed on the side-window-filtering method. The results of eight convolution kernels for side windows are computed simultaneously to improve the processing speed. Due to the proposed side-window-filtering-based blind pixel compensation algorithm, blind pixels can be effectively compensated while details in the image are preserved. Before image output, we also incorporated lightweight histogram equalization to make the processed image more easily observable to the human eyes. The proposed lightweight infrared image processor is implemented on Xilinx XC7A100T-2. Our proposed lightweight infrared image processor costs 10,894 LUTs, 9367 FFs, 4 BRAMs, and 5 DSP48. Under a 50 MHz clock, the processor achieves a speed of 30 frames per second at the cost of 1800 mW. The maximum operating frequency of our proposed processor can reach 186 MHz. Compared with existing similar works, our proposed infrared image processor incurs minimal resource overhead and has lower power consumption.

3.
Am J Orthod Dentofacial Orthop ; 165(5): 520-532.e3, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38276930

RESUMO

INTRODUCTION: The objective of this study was to investigate the 2-year postoperative change and influencing factors of the upper airway after mandibular advancement with maxillary setback surgery for patients with a skeletal Class II relationship. METHODS: Fifty-seven participants who underwent mandibular advancement with maxillary setback surgery were enrolled consecutively. Cone-beam computed tomography was performed preoperatively, 3 months postoperatively (T1), and 2 years (T2) postoperatively. All parameters were measured using Dolphin Imaging software (Dolphin Imaging and Management Solutions, Chatsworth, Calif). RESULTS: The total volume (V), minimum cross-sectional area (CSAmin), and glossopharynx increased significantly in both the short-term (V, 13.33%; CSAmin, 33.03%; glossopharynx, 26.73%) and long-term (V, 10.19%; CSAmin, 23.18%; glossopharynx, 18.27%) after the surgery. Mandibular advancement, mandibular width increase, preoperative CSAmin, and body mass index (BMI) significantly affected 2-year postoperative V increases. Mandibular advancement and BMI significantly affected 2-year postoperative glossopharynx increases. Backward movement of point PNS may lead to a reduction of the nasopharynx; however, downward movement of point PNS, upward movement of point A, and increased maxillary width may compensate for this effect by increasing the likelihood of the nasopharynx opening. Furthermore, mandibular body length at T1 is positively associated with relapse rate ([T2 - T1] / T1) of V and CSAmin. CONCLUSIONS: Mandibular advancement amount, mandibular width increase, preoperative CSAmin, and BMI are the 4 factors for long-term V changes. Patients with a longer mandibular body length might have a lower relapse rate.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Má Oclusão Classe II de Angle , Avanço Mandibular , Maxila , Humanos , Avanço Mandibular/métodos , Má Oclusão Classe II de Angle/cirurgia , Má Oclusão Classe II de Angle/diagnóstico por imagem , Feminino , Masculino , Seguimentos , Maxila/cirurgia , Adulto , Faringe/diagnóstico por imagem , Faringe/anatomia & histologia , Adulto Jovem , Resultado do Tratamento , Cefalometria , Fatores de Tempo , Adolescente
4.
Ann Neurol ; 92(3): 512-526, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35700120

RESUMO

OBJECTIVE: Oculopharyngodistal myopathy (OPDM) is an adult-onset neuromuscular disease characterized by progressive ptosis, dysarthria, ophthalmoplegia, and distal muscle weakness. Recent studies revealed that GGC repeat expansions in 5'-UTR of LRP12, GIPC1, and NOTCH2NLC are associated with OPDM. Despite these advances, approximately 30% of OPDM patients remain genetically undiagnosed. Herein, we aim to investigate the genetic basis for undiagnosed OPDM patients in two unrelated Chinese Han families. METHODS: Parametric linkage analysis was performed. Long-read sequencing followed by repeat-primed polymerase chain reaction and amplicon length polymerase chain reaction were used to determine the genetic cause. Targeted methylation sequencing was implemented to detect epigenetic changes. The possible pathogenesis mechanism was investigated by quantitative polymerase chain reaction, immunoblotting, RNA fluorescence in situ hybridization, and immunofluorescence staining of muscle biopsy samples. RESULTS: The disease locus was mapped to 12q24.3. Subsequently, GGC repeat expansion in the promoter region of RILPL1 was identified in six OPDM patients from two families, findings consistent with a founder effect, designated as OPDM type 4. Targeted methylation sequencing revealed hypermethylation at the RILPL1 locus in unaffected individuals with ultralong expansion. Analysis of muscle samples showed no significant differences in RILPL1 mRNA or RILPL1 protein levels between patients and controls. Public CAGE-seq data indicated that alternative transcription start sites exist upstream of the RefSeq-annotated RILPL1 transcription start site. Strand-specific RNA-seq data revealed bidirectional transcription from the RILPL1 locus. Finally, fluorescence in situ hybridization/immunofluorescence staining showed that both sense and antisense transcripts formed RNA foci, and were co-localized with hnRNPA2B1 and p62 in the intranuclear inclusions of OPDM type 4 patients. INTERPRETATION: Our findings implicate abnormal GGC repeat expansions in the promoter region of RILPL1 as a novel genetic cause for OPDM, and suggest a methylation mechanism and a potential RNA toxicity mechanism are involved in OPDM type 4 pathogenesis. ANN NEUROL 2022;92:512-526.


Assuntos
Distrofias Musculares , Adulto , Humanos , Hibridização in Situ Fluorescente , Corpos de Inclusão Intranuclear/patologia , Distrofias Musculares/genética , Linhagem , RNA , Expansão das Repetições de Trinucleotídeos/genética
5.
Opt Lett ; 48(18): 4837-4840, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707915

RESUMO

The Gaussian-modulated coherent state (GMCS) is a well-known continuous-variable quantum key distribution (CV-QKD) protocol that is robust to incoherent background noise and can effectively suppress ambient light in free space. However, it is difficult to implement this protocol in free space using existing polarization coding schemes. In this Letter, we propose a polarization coding structure based on a self-compensating fiber Sagnac interferometer, which can reduce the required modulation voltage by two orders of magnitude and achieve fast and arbitrary polarization modulation, and experimentally demonstrate polarization coding-based GMCS CV-QKD for, it is believed, the first time. The proposed polarization modulation structure, which uses off-the-shelf fiber components, is compact, simple, and suitable for mobile terminals, such as flying lifts.

6.
Opt Lett ; 48(7): 1558-1561, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221709

RESUMO

The round-robin differential phase shift (RRDPS) quantum key distribution (QKD) protocol is the only one that does not require monitoring of signal disturbance. Moreover, it has been proven that RRDPS has excellent performance of resistance to finite-key effects and high error rate tolerance. However, the existing theories and experiments do not take the afterpulse effects into account, which cannot be neglected in high-speed QKD systems. Here, we propose a tight finite-key analysis with afterpulse effects. The results show that the non-Markovian afterpulse RRDPS model optimizes the system performance considering afterpulse effects. The advantage of RRDPS over decoy-state BB84 under short-time communication still holds at typical values of afterpulse.

7.
Phys Rev Lett ; 131(11): 110802, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774301

RESUMO

The passive approach to quantum key distribution (QKD) consists of removing all active modulation from the users' devices, a highly desirable countermeasure to get rid of modulator side channels. Nevertheless, active modulation has not been completely removed in QKD systems so far, due to both theoretical and practical limitations. In this Letter, we present a fully passive time-bin encoding QKD system and report on the successful implementation of a modulator-free QKD link. According to the latest theoretical analysis, our prototype is capable of delivering competitive secret key rates in the finite key regime.

8.
Langmuir ; 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629142

RESUMO

Lollingite (FeAs2) is considered an arsenic-bearing mineral that is oxidized faster than arsenopyrite. The geometric configuration, chemical valence bond, and microscopic reaction of the oxidation on the surface of lollingite were systematically studied, which are of great significance for understanding the mechanism of oxidative dissolution. X-ray photoelectron spectroscopy (XPS) measurements and density functional theory (DFT) calculations were carried out to characterize the (101) surface oxidation process of lollingite under the O2/O2 + H2O conditions. XPS results confirmed that the participation of water molecules can promote the formation of abundant OH structures on the surface of lollingite, while the relative concentration of O, As(III), and Fe(III) increased. Moreover, the DFT results demonstrated that the (101) As-terminal plane of FeAs2 was the most stable surface with the lowest surface energy. H2O molecules were physically adsorbed onto the Fe atoms of the lollingite surface, while oxygen molecules can readily be adsorbed on the Fe-As2 site by chemical adsorption processes. The oxidation process of the lollingite surface with water includes the following mechanisms: adsorption, dissociation, formation of the hydrogen bond, and desorption. The dissociation of the H2O molecule into OH and H led to the hydroxylation of both Fe and As atoms and the formation of hydrogen bonding. The participation of H2O molecules can also reduce the reaction energy barrier and accelerate the oxidation reaction of the lollingite surface, especially as far as the water dissociation and formation of hydrogen bonds are concerned. According to PDOS data, there is considerable hybridization between the d orbitals of bonded Fe atoms and the p orbitals of O atoms, as well as between the p orbitals of bonded As atoms and the p orbitals of O atoms. Due to a strong propensity for orbital hybridization and bonding between the s orbitals of the H atoms in H2O molecules and the p orbitals of the O atoms on the (101) surface, water molecules have the ability to speed up the oxidation on the surface.

9.
Appl Opt ; 62(5): 1175-1182, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36821215

RESUMO

Improving imaging quality while reducing the sampling time simultaneously is a crucial challenge that limits the practical application of temporal ghost imaging (TGI). To improve the performance of TGI, various methods have been proposed and verified. However, a work analyzing in detail the influence of intensity accuracy and detection noise of TGI is still absent. Here, we establish an evaluation model to quantify the imaging quality of TGI and differential TGI (DTGI). Our model considers the intensity detection accuracy, threshold, and noise of the test path during image reconstruction and quantifies their influences by developing general imaging formulas of (D)TGI. We also simulate the imaging of (D)TGI numerically. The evaluation demonstrates that (D)TGI is relatively not sensitive to detection accuracy and thresholds of the test path, and image quality is degraded slightly even when those parameters turn much worse. (D)TGI is relatively robust to detection noise but will be unable to reconstruct the object when noise is too strong. DTGI does not show clear advantages over TGI. Our work develops an effective model to quantify the image quality with practical parameters and is significant to real applications of (D)TGI.

10.
Am J Orthod Dentofacial Orthop ; 164(2): e27-e42, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37245126

RESUMO

INTRODUCTION: This study aimed to analyze the effects of premolar extraction treatment with vertical control on changes in the anatomy and aerodynamics of the oropharynx in Class II hyperdivergent malocclusion with nonsevere crowding. METHODS: Thirty-nine patients with Class II hyperdivergent malocclusion were enrolled consecutively. All the participants underwent 4 premolar extractions. The high-pull J-hook and mini-implants were used to provide vertical control. Cone-beam computed tomography was performed before and after treatment. The participants were divided into a decreased lower vertical facial height group (n = 23) and an increased lower vertical facial height group (n = 16) on the basis of superimposition. The aerodynamic characteristics, including airway resistance (inspiration, Rin; expiration, Rex) and maximum velocity (inspiration, Vmaxin; expiration, Vmaxex) at inspiration and expiration, were calculated using computational fluid dynamics. Anatomic characteristics, including volume and cross-sectional area (CSAmin), were measured using the Dolphin Imaging software (Dolphin Imaging and Management Solutions, Chatsworth, Calif). RESULTS: After treatment, the median volume and CSAmin increased by 2357 mm3 and 43 mm2, respectively, and median Rin and Vmaxex decreased by 0.15 Pa/L/min and 0.24 m×s-1, respectively, in decreased lower vertical facial height group. In contrast, the median CSAmin decreased by 9.5 mm2 in the increased lower vertical facial height group. All the changes were statistically significant (all P <0.05). Significant differences in volume, CSAmin, Rin, and Vmaxex were observed between the 2 groups. CONCLUSIONS: Vertical control might improve the anatomic and aerodynamic characteristics of the oropharyngeal airway during premolar extraction treatment of Class II hyperdivergent malocclusion with nonsevere crowding.


Assuntos
Má Oclusão Classe II de Angle , Má Oclusão , Humanos , Dente Pré-Molar/diagnóstico por imagem , Dente Pré-Molar/cirurgia , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/cirurgia , Orofaringe/diagnóstico por imagem , Orofaringe/anatomia & histologia , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos
11.
BMC Oral Health ; 23(1): 642, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670292

RESUMO

BACKGROUND: Given the difficulties or incapacity of teeth movement in orthodontic treatment, the ways to speed tooth movement must be investigated. Besides, nonsteroidal anti-inflammatory drugs (NSAIDs) were utilized to treat pain caused by tooth movement during orthodontic treatment. The purpose of this study is to examine the impact of aspirin and low-frequency high-intensity ultrasound (LFHIU) on rat orthodontic tooth movement in rats. METHODS: Thirty-six male Sprague-Dawley rats were divided into three groups: orthodontic (O), ultrasound-treated orthodontic (OU), and ultrasound-treated orthodontic with aspirin gavage (OUA) group. In the OU and OUA group, LFHIU (44 W/cm2, 28 kHz) was applied to the buccal side of the maxillary first molar alveolar bone for 10 s every day. In the OUA group, aspirin was given by gavage every day. The rats were sacrificed on days 1, 3, 7, and 14. RESULTS: After ultrasonic treatment, the speed of tooth movement was increased by about 1.5 times. And the number of osteoclasts considerably increased by about 2 times. However, they decreased slightly after aspirin gavage. By Applying ultrasound therapy, Receptor Activator for Nuclear Factor-κ B Ligand (RANKL) levels in periodontal tissue were elevated. Aspirin was able to reduce these increases. Results from Micro Computed Tomography (Micro-CT) revealed that bone mineral density decreased by about 1/5 after ultrasound treatment on the compression side. The rate of bone mineral apposition indicated that bone was forming under tension, and that of the OU group increased by about 1.3 times that O group. CONCLUSIONS: Although aspirin slowed this trend, LFHIU still enhanced overall tooth mobility in orthodontic treatment.


Assuntos
Aspirina , Técnicas de Movimentação Dentária , Masculino , Ratos , Animais , Ratos Sprague-Dawley , Microtomografia por Raio-X , Ultrassonografia
12.
Entropy (Basel) ; 25(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36832625

RESUMO

Quantum key distribution (QKD) allows two remote parties to share information-theoretic secret keys. Many QKD protocols assume the phase of encoding state can be continuous randomized from 0 to 2π, which, however, may be questionable in the experiment. This is particularly the case in the recently proposed twin-field (TF) QKD, which has received a lot of attention since it can increase the key rate significantly and even beat some theoretical rate-loss limits. As an intuitive solution, one may introduce discrete-phase randomization instead of continuous randomization. However, a security proof for a QKD protocol with discrete-phase randomization in the finite-key region is still missing. Here, we develop a technique based on conjugate measurement and quantum state distinguishment to analyze the security in this case. Our results show that TF-QKD with a reasonable number of discrete random phases, e.g., 8 phases from {0,π/4,π/2,…,7π/4}, can achieve satisfactory performance. On the other hand, we find the finite-size effects become more notable than before, which implies that more pulses should be emit in this case. More importantly, as a the first proof for TF-QKD with discrete-phase randomization in the finite-key region, our method is also applicable in other QKD protocols.

13.
J Minim Access Surg ; 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37843162

RESUMO

Introduction: In immunotherapy, antibodies are activated to block immune checkpoints, resist tumour immunosuppression, shrink tumours and prevent a recurrence. As the science behind tumour immunotherapy continuously develops and improves, neoadjuvant immunotherapy bears more prominent advantages: antigen exposure not only enhances the degree of tumour-specific T-cell response but also prolongs the duration of actions. In this study, we evaluated the efficacy and safety of McKeown minimally invasive oesophagectomy (McKeown MIO) following neoadjuvant immunotherapy combined with chemotherapy (NICT) in patients with locally advanced oesophageal cancer (OC). Patients and Methods: In this retrospective study, 94 patients underwent either NICT or neoadjuvant chemotherapy (NCT) followed by MIO at our institution from January 2020 to October 2022. We assessed the therapy-related adverse events and perioperative outcomes and compared them between the two groups. Results: After completing at least two cycles of neoadjuvant therapy, all patients underwent McKeown MIO with negative margins within 4-7 weeks. Demographic data of the two cohorts were similar. Regarding perioperative characteristics, the median intraoperative blood loss was 50 ml in the NICT group, lower than that of the NCT group (100 ml, P < 0.05). In addition, the NICT group had significantly more harvested lymph nodes than the NCT group (P < 0.05). No significant differences were found in post-operative complications. The rate of objective response rate in the NICT group was higher than that in the NCT group (88.3% vs. 58.8%). Regarding tumour regression, the number of patients with TRG Grades 1-3 in the NICT group was more than that in the NCT. Adverse events experienced by the two groups included anaemia and elevated transaminase. We found no difference in the adverse events between the two groups. Conclusions: This study showed the efficacy and feasibility of NICT followed by McKeown MIO in treating locally advanced OC.

14.
BMC Plant Biol ; 22(1): 502, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36289462

RESUMO

BACKGROUND: Soil salinization has become a global problem restricting the seed yield and quality of crops, including wheat (Triticum aestivum L.). Salinity significantly alters plant morphology and severely disrupts physiological homeostasis. Salt tolerance of wheat has been widely studied whereas core ion transporters responsive to salt stress remain elusive. RESULTS: In this study, the wheat seedlings were subjected to salinity toxicity for morpho-physiological and transcriptomic analysis of wheat salt tolerance. There was a inversely proportional relationship between salt concentrations and morpho-physiological parameters. Under the condition of 100 mM NaCl, the H2O2, O2-, MDA content and membrane permeability were significantly increased whereas the chlorophyll content was markedly decreased. Under salt stress, a larger proportion of Na+ was partitioned in the roots than in the shoots, which had a lower Na+/K+ ratio and proline content. Salt stress also obviously affected the homeostasis of other cations. Genome-wide transcriptomic analysis showed that a total of 2,807 and 5,570 differentially expressed genes (DEGs) were identified in the shoots and roots, respectively. Functionality analysis showed that these DEGs were mainly enriched in the KEGG pathways related to carbon metabolism, phenylalanine, and amino acid biosynthesis, and were primarily enriched in the GO terms involving proline metabolism and redox processes. The Na+ transporter genes were upregulated under salt stress, which repressed the gene expression of the K+ transporters. Salt stress also significantly elevated the expression of the genes involved in osmoregulation substances biosynthesis, and obviously affected the expression profiling of other cation transporters. Co-expression network analysis identified TaNHX6-D5/TaNHX4-B7 and TaP5CS2-B3 potentially as core members regulating wheat salt tolerance. CONCLUSIONS: These results might help us fully understand the morpho-physiological and molecular responses of wheat seedlings to salt stress, and provide elite genetic resources for the genetic modification of wheat salt tolerance.


Assuntos
Plântula , Triticum , Triticum/metabolismo , Plântula/genética , Plântula/metabolismo , Osmorregulação , Peróxido de Hidrogênio/metabolismo , Cloreto de Sódio/metabolismo , Estresse Salino/genética , Salinidade , Sódio/metabolismo , Clorofila/metabolismo , Prolina/metabolismo , Carbono/metabolismo , Nutrientes , Solo , Fenilalanina/metabolismo , Aminoácidos/metabolismo , Estresse Fisiológico/genética
15.
Opt Express ; 30(14): 25474-25485, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237076

RESUMO

Quantum random number generators (QRNGs) promise secure randomness generation based on the foundational unpredictability of quantum mechanics. However, the unavoidable gaps between theoretical models and practical devices could lead to security invalidation. Recently, a source-independent quantum random number generator (SI-QRNG) has been proposed to solve the issue of uncharacteristic sources. However, in most current analyses of SI-QRNG protocols, the security proofs with imperfect measurements are individual for different factors and very sensitive to small deviations from theoretical models. Here, we establish a unified model for imperfect measurements in the SI-QRNG and provide a tight rate bound based on the uncertainty relation for smooth entropies. Then the performance with large device imperfections is evaluated and the randomness rate in our model can approach a similar order of magnitude of the rate upper bound in common discrete variable QRNGs. In addition, by utilizing the daily illumination and measurement devices with large imperfections, we experimentally demonstrate our scheme at the rate of the order of magnitude of Mbps.

16.
Opt Express ; 30(22): 39911-39921, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298933

RESUMO

In chip-based quantum key distribution (QKD) systems, the non-ideal quantum state preparation due to the imperfect electro-optic phase modulators (EOPM) decreases the secret key rate and introduces potential vulnerabilities. We propose and implement an on-chip transmittance-invariant phase modulator (TIPM) to solve this problem. Simulated and experimental results show that TIPM can eliminate the correlation between phase, intensity, and polarization of quantum states caused by phase-dependent loss. The design can tolerate a significant fabrication mismatch and is universal to multi-material platforms. Furthermore, TIPM increases the modulation depth achievable by EOPMs in standard process design kit (PDK). The proposal of TIPM can improve the practical security and performance of the chip-based QKD systems.

17.
Opt Express ; 30(16): 28534-28549, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36299046

RESUMO

There is no doubt that measurement-device-independent quantum key distribution (MDI-QKD) is a crucial protocol that is immune to all possible detector side channel attacks. In the preparation phase, a simulation model is usually employed to get a set of optimized parameters, which is utilized for getting a higher secure key rate in reality. With the implementation of high-speed QKD, the afterpulse effect which is an intrinsic characteristic of the single-photon avalanche photodiode is no longer ignorable, this will lead to a great deviation compared with the existing analytical model. Here we develop an afterpulse-compatible MDI-QKD model to get the optimized parameters. Our results indicate that by using our afterpulse-compatible model, we can get a much higher key rate than the prior afterpulse-omitted model. It is significant to take the afterpulse effect into consideration because of the improvement of the system working frequency.

18.
J Exp Bot ; 73(22): 7516-7537, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36063365

RESUMO

Cadmium (Cd) is a highly toxic heavy metal that readily enters cereals, such as wheat, via the roots and is translocated to the shoots and grains, thereby posing high risks to human health. However, the vast and complex genome of allohexaploid wheat makes it challenging to understand Cd resistance and accumulation. In this study, a Cd-resistant cultivar of wheat, 'ZM1860', and a Cd-sensitive cultivar, 'ZM32', selected from a panel of 442 accessions, exhibited significantly different plant resistance and grain accumulation. We performed an integrated comparative analysis of the morpho-physiological traits, ionomic and phytohormone profiles, genomic variations, transcriptomic landscapes, and gene functionality in order to identify the mechanisms underlying these differences. Under Cd toxicity, 'ZM1860' outperformed 'ZM32', which showed more severe leaf chlorosis, poorer root architecture, higher accumulation of reactive oxygen species, and disordered phytohormone homeostasis. Ionomics showed that 'ZM32' had a higher root-to-shoot translocation coefficient of Cd and accumulated more Cd in the grains than 'ZM1860'. Whole-genome re-sequencing (WGS) and transcriptome sequencing identified numerous DNA variants and differentially expressed genes involved in abiotic stress responses and ion transport between the two genotypes. Combined ionomics, transcriptomics, and functional gene analysis identified the plasma membrane-localized heavy metal ATPase TaHMA2b-7A as a crucial Cd exporter regulating long-distance Cd translocation in wheat. WGS- and PCR-based analysis of sequence polymorphisms revealed a 25-bp InDel site in the promoter region of TaHMA2b-7A, and this was probably responsible for the differential expression. Our multiomics approach thus enabled the identification of a core transporter involved in long-distance Cd translocation in wheat, and it may provide an elite genetic resource for improving plant Cd resistance and reducing grain Cd accumulation in wheat and other cereal crops.


Assuntos
Cádmio , Triticum , Multiômica , Triticum/genética
19.
Opt Lett ; 47(12): 3111-3114, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35709063

RESUMO

The quantum-classical coexistence can be implemented based on wavelength division multiplexing (WDM), but due to Raman noise, the wavelength spacing between quantum and classical signals and launch power from classical channels are restricted. Space division multiplexing (SDM) can now be availably achieved by multicore fiber (MCF) to reduce Raman noise, thereby loosening the restriction for coexistence in the same band and obtaining a high communication capacity. In this paper, we realize the quantum-classical coexistence over a 7-core MCF. Based on the SDM, the highest launch power of 25 dBm is achieved which has been extended nearly 19 times in previous work. Moreover, both the quantum and classical channels are allocated in the C-band and the minimum wavelength spacing between them is only 1.6 nm. The coexistence system eliminates the need for adding a narrowband filter.

20.
Phys Rev Lett ; 129(5): 050506, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35960590

RESUMO

Generating random numbers plays an important role in many scientific applications. Compared to pseudorandom number generators, a quantum device is capable of generating true random numbers by the laws of quantum mechanics. However, information-theoretical secure random numbers are regularly based on a perfect device model, which may deviate from a real-world device. To close this gap, we propose a quantum random number generation protocol and experimentally demonstrate it. In our protocol, we make no assumptions about the source. Some reasonable assumptions on the trusted two-dimensional measurement are needed, but we do not require a detailed characterization. Even if considering the most general quantum attack and using the general sources, we achieve a randomness generation rate of over 1 Mbps with a universal composable security parameter of 10^{-10}.

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