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1.
J Transl Med ; 21(1): 536, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573305

RESUMO

BACKGROUND: Studies have examined the effect of weight change on osteoporosis, but the results were controversial. Among them, few had looked at weight change over the life span. This study aimed to fill this gap and investigate the association between lifetime body mass index (BMI) trajectories and bone loss. METHODS: In this cross-sectional study, participants at age 50 and above were selected from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Dual-energy X-ray Absorptiometry was used to measure the bone mineral density at the femoral neck and lumbar spine. Standard BMI criteria were used, with < 25 kg/m2 for normal, 25-29.9 kg/m2 for overweight, and ≥ 30 kg/m2 for obesity. The latent class trajectory model (LCTM) was used to identify BMI trajectories. Multinomial logistic regression models were fitted to evaluate the association between different BMI trajectories and osteoporosis or osteopenia. RESULTS: For the 9,706 eligible participants, we identified four BMI trajectories, including stable (n = 7,681, 70.14%), slight increase (n = 1253, 12.91%), increase to decrease (n = 195, 2.01%), and rapid increase (n = 577, 5.94%). Compared with individuals in the stable trajectory, individuals in the rapid increase trajectory had higher odds of osteoporosis (OR = 2.25, 95% CI 1.19-4.23) and osteopenia (OR = 1.49, 95% CI 1.02-2.17). This association was only found in the lumbar spine (OR = 2.11, 95% CI 1.06-4.2) but not in the femoral neck. In early-stage (age 25-10 years ago) weight change, staying an obesity and stable weight seemed to have protective effects on osteoporosis (OR = 0.26, 95% CI 0.08-0.77) and osteopenia (OR = 0.46, 95% CI 0.25-0.84). Meanwhile, keeping an early-stage stable and overweight was related to lower odds of osteopenia (OR = 0.53, 95% CI 0.34-0.83). No statistically significant association between recent (10 years ago to baseline) weight change and osteoporosis was found. CONCLUSIONS: Rapid and excess weight gain during adulthood is associated with a higher risk of osteoporosis. But this association varies by skeletal sites. Maintaining stable overweight and obesity at an early stage may have potentially beneficial effects on bone health.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , Humanos , Adulto , Pessoa de Meia-Idade , Índice de Massa Corporal , Inquéritos Nutricionais , Estudos Transversais , Sobrepeso/epidemiologia , Sobrepeso/complicações , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/complicações , Osteoporose/epidemiologia , Osteoporose/complicações , Densidade Óssea , Aumento de Peso , Obesidade/complicações , Absorciometria de Fóton
2.
Opt Express ; 31(19): 30650-30657, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710604

RESUMO

We developed a mobile superconducting strip photon detector (SSPD) system operated in a liquid-helium Dewar. By adopting highly disordered NbTiN thin films, we successfully enhanced the detection performance of superconducting strips at higher operation temperatures and realized SSPDs with nearly saturated detection efficiency at 4.2 K. Then we customized a compact liquid-helium Dewar and a battery-based electronic module to minimize the SSPD system. A mobile SSPD system was integrated, which showed a system detection efficiency of 72% for a 1550 nm wavelength with a dark count rate of 200 cps and a timing jitter of 67.2 ps. The system has a weight of 40 kg and a power consumption of 500 mW, which can work continuously for 20 hours. The metrics can be further optimized in accordance with the various practical application platforms, such as aircraft, drones, etc.

3.
Phys Rev Lett ; 130(21): 210801, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295116

RESUMO

Quantum key distribution (QKD) aims to generate secure private keys shared by two remote parties. With its security being protected by principles of quantum mechanics, some technology challenges remain towards practical application of QKD. The major one is the distance limit, which is caused by the fact that a quantum signal cannot be amplified while the channel loss is exponential with the distance for photon transmission in optical fiber. Here using the 3-intensity sending-or-not-sending protocol with the actively-odd-parity-pairing method, we demonstrate a fiber-based twin-field QKD over 1002 km. In our experiment, we developed a dual-band phase estimation and ultra-low noise superconducting nanowire single-photon detectors to suppress the system noise to around 0.02 Hz. The secure key rate is 9.53×10^{-12} per pulse through 1002 km fiber in the asymptotic regime, and 8.75×10^{-12} per pulse at 952 km considering the finite size effect. Our work constitutes a critical step towards the future large-scale quantum network.


Assuntos
Fótons , Física , Feminino , Gravidez , Humanos , Frequência Cardíaca
4.
Neurochem Res ; 48(10): 3099-3112, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37336823

RESUMO

Purinergic receptor P2X4 (P2X4R) plays an essential role in neuropathic pain. However, the specific mechanism needs to be clarified. Botulinum toxin type A is a neurotoxin produced by Clostridium botulinum type A. This study found that intrathecal injection of botulinum toxin type A produced an excellent analgesic effect in a rat model of chronic constriction sciatic nerve injury and inhibited the activation of P2X4R, microglia, and astrocytes. The administration of a P2X4R activator can up-regulate the expression of P2X4R and eliminate the analgesic effect of intrathecal injection of botulinum toxin type A. In addition, we found that microglia and astrocytes in the spinal cord of rats injected with botulinum toxin type A were reactivated after administration of the P2X4R activator. Our results suggest that intrathecal injection of botulinum toxin type A has an analgesic effect in a rat model of chronic constriction sciatic nerve injury by inhibiting the activation of P2X4R in the spinal cord.


Assuntos
Toxinas Botulínicas Tipo A , Neuralgia , Ratos , Masculino , Animais , Toxinas Botulínicas Tipo A/uso terapêutico , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Medula Espinal/metabolismo , Injeções Espinhais , Analgésicos/uso terapêutico , Analgésicos/metabolismo , Hiperalgesia/metabolismo
5.
Mol Cell Biochem ; 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648958

RESUMO

In animal studies, sodium-glucose co-transporter-2 inhibitors-such as empagliflozin-have been shown to improve heart failure and impaired cardiac contractility induced by anthracyclines-including doxorubicin-although the therapeutic mechanism remains unclear. Moreover, abnormalities in Ca2+ handling within ventricular myocytes are the predominant feature of heart failure. Accordingly, this study aimed to investigate whether empagliflozin can alleviate Ca2+ handling disorders induced by acute doxorubicin exposure and elucidate the underlying mechanisms. To this end, ventricular myocytes were isolated from C57BL/6 mice. Contraction function, Ca2+ handling, and mitochondrial reactive oxygen species (ROS) generation were then evaluated using IonOptix or confocal microscopy. Ca2+ handling proteins were detected by western blotting. Results show that incubation with 1 µmol/L of doxorubicin for 120-min impaired cardiac contractility in isolated myocytes, which was significantly alleviated by pretreatment with 1 µmol/L of empagliflozin. Doxorubicin also markedly induced Ca2+ handling disorders, including decreased Ca2+ transients, prolonged Ca2+ transient decay time, enhanced frequency of Ca2+ sparks, and decreased Ca2+ content in the sarcoplasmic reticulum. These dysregulations were improved by pretreatment with empagliflozin. Moreover, empagliflozin effectively inhibited doxorubicin-induced mitochondrial ROS production in isolated myocytes and rescued doxorubicin-induced oxidation of Ca2+/calmodulin-dependent protein kinase II (ox-CaMKII) and CaMKII-dependent phosphorylation of RyR2. Similarly, preincubation with 10 µmol/L Mito-TEMPO mimicked the protective effects of empagliflozin. Collectively, Empagliflozin ameliorated the doxorubicin-induced contraction malfunction and Ca2+-handling disorders. These findings suggest that empagliflozin alleviates Ca2+-handling disorders by improving ROS production in the mitochondria and alleviating the enhanced oxidative CaMKII signaling pathway induced by doxorubicin.

6.
Ren Fail ; 45(2): 2285869, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38044851

RESUMO

Acute kidney injury (AKI) is a common disorder without effective therapy yet. Renal ischemia/reperfusion (I/R) injury is a common cause of AKI. MicroRNA miR-192-5p has been previously reported to be upregulated in AKI models. However, its functional role in renal I/R injury is not fully understood. This study aimed to investigate the effects and the underlying mechanism of miR-192-5p in renal I/R progression. Hypoxia/reoxygenation (H/R)-induced cell injury model in HK-2 cells and I/R-induced renal injury model in mice were established in this study. Cell counting kit-8 assay was performed to determine cell viability. Quantitative real-time PCR and western blot analysis were performed to detect gene expressions. Hematoxylin-eosin and periodic acid-Schiff staining were performed to observe the histopathological changes. Enzyme-linked immunosorbent assay was performed to detect the kidney markers' expression. In vivo and in vitro results showed that miR-192-5p was up-regulated in the I/R-induced mice model and H/R-induced cell model, and miR-192-5p overexpression exacerbated I/R-induced renal damage. Then, the downstream target of miR-192-5p was analyzed by combining the differentially expressed mRNAs and the predicted genes and confirmed using a dual-luciferase reporter assay. It was found that miR-192-5p was found to regulate fat mass and obesity-associated (FTO) protein expression by directly targeting the 3' untranslated region of FTO mRNA. Moreover, in vivo and in vitro studies unveiled that FTO overexpression alleviated renal I/R injury and promoted HK-2 cell viability via stimulating autophagy flux. In conclusion, miR-192-5p aggravated I/R-induced renal injury by blocking autophagy flux via down-regulating FTO.


Assuntos
Injúria Renal Aguda , MicroRNAs , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Injúria Renal Aguda/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Apoptose , Rim/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Obesidade/complicações , Obesidade/genética , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo
7.
Entropy (Basel) ; 25(3)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36981311

RESUMO

Link prediction is a hot issue in information filtering. Link prediction algorithms, based on local similarity indices, are widely used in many fields due to their high efficiency and high prediction accuracy. However, most existing link prediction algorithms are available for unweighted networks, and there are relatively few studies for weighted networks. In the previous studies on weighted networks, some scholars pointed out that links with small weights play a more important role in link prediction and emphasized that weak-ties theory has a significant impact on prediction accuracy. On this basis, we studied the edges with different weights, and we discovered that, for edges with large weights, this weak-ties theory actually does not work; Instead, the weak-ties theory works in the prediction of edges with small weights. Our discovery has instructive implications for link predictions in weighted networks.

8.
Entropy (Basel) ; 26(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38275487

RESUMO

Malicious attacks can cause significant damage to the structure and functionality of complex networks. Previous research has pointed out that the ability of networks to withstand malicious attacks becomes weaker when networks are coupled. However, traditional research on improving the robustness of networks has focused on individual low-order or higher-order networks, lacking studies on coupled networks with higher-order and low-order networks. This paper proposes a method for optimizing the robustness of coupled networks with higher-order and low-order based on a simulated annealing algorithm to address this issue. Without altering the network's degree distribution, the method rewires the edges, taking the robustness of low-order and higher-order networks as joint optimization objectives. Making minimal changes to the network, the method effectively enhances the robustness of coupled networks. Experiments were conducted on Erdos-Rényi random networks (ER), scale-free networks (BA), and small-world networks (SW). Finally, validation was performed on various real networks. The results indicate that this method can effectively enhance the robustness of coupled networks with higher-order and low-order.

9.
Mol Biol Evol ; 38(12): 5752-5768, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34581782

RESUMO

As drivers of evolutionary innovations, new genes allow organisms to explore new niches. However, clear examples of this process remain scarce. Bamboos, the unique grass lineage diversifying into the forest, have evolved with a key innovation of fast growth of woody stem, reaching up to 1 m/day. Here, we identify 1,622 bamboo-specific orphan genes that appeared in recent 46 million years, and 19 of them evolved from noncoding ancestral sequences with entire de novo origination process reconstructed. The new genes evolved gradually in exon-intron structure, protein length, expression specificity, and evolutionary constraint. These new genes, whether or not from de novo origination, are dominantly expressed in the rapidly developing shoots, and make transcriptomes of shoots the youngest among various bamboo tissues, rather than reproductive tissue in other plants. Additionally, the particularity of bamboo shoots has also been shaped by recent whole-genome duplicates (WGDs), which evolved divergent expression patterns from ancestral states. New genes and WGDs have been evolutionarily recruited into coexpression networks to underline fast-growing trait of bamboo shoot. Our study highlights the importance of interactions between new genes and genome duplicates in generating morphological innovation.


Assuntos
Genoma , Poaceae , Evolução Biológica , Poaceae/metabolismo , Transcriptoma
10.
Curr Issues Mol Biol ; 44(11): 5579-5592, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36354690

RESUMO

Plants that are adapted to harsh environments offer enormous opportunity to understand stress responses in ecological systems. Stipa capillacea is widely distributed in the frigid and arid region of the Tibetan Plateau, but its signal transduction system under cold stress has not been characterized. In this study, we isolated a cDNA encoding the signal transduction protein, ScCBL6, from S. capillacea, and evaluated its role in cold tolerance by ectopically expressing it in Arabidopsis. Full-length ScCBL6 encode 227 amino acids, and are clustered with CBL6 in Stipa purpurea and Oryza sativa in a phylogenetic analysis. Compared with tolerance in wild-type (WT) plants, ScCBL6-overexpressing plants (ScCBL6-OXP) were more tolerant to cold stress but not to drought stress, as confirmed by their high photosynthetic capacity (Fv/Fm) and survival rate under cold stress. We further compared their cold-responsive transcriptome profiles by RNA sequencing. In total, 3931 genes were differentially expressed by the introduction of ScCBL6. These gene products were involved in multiple processes such as the immune system, lipid catabolism, and secondary metabolism. A KEGG pathway analysis revealed that they were mainly enriched in plant hormone signal transduction and biomacromolecule metabolism. Proteins encoded by differentially expressed genes were predicted to be localized in chloroplasts, mitochondria, and vacuoles, suggesting that ScCBL6 exerts a wide range of functions. Based on its tonoplast subcellular location combined with integrated transcriptome and physiological analyses of ScCBL6-OXP, we inferred that ScCBL6 improves plant cold stress tolerance in Arabidopsis via the regulation of photosynthesis, redox status, and tonoplast metabolite transporters.

11.
Virol J ; 19(1): 187, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376944

RESUMO

Porcine circovirus 3 (PCV3) is a newly emerging virus and has been found associated with porcine dermatitis and nephropathy syndrome in pigs. Compared with PCV2, research into PCV3 cap gene sequencing is deficient. To investigate the prevalence and genotype distribution of PCV3, we collected 1291 samples from 211 pig farms throughout 15 provinces and municipalities. 312 out of 1291 samples were tested positive by PCR. We further sequenced and analyzed 164 PCR-positive samples. The majority (61.8%) of isolates we sequenced belong to genotype PCV3c. PCV3c is also the dominant genotype in Hubei, Hunan, Hebei province and Chongqing city. We found 3 sites under positive selection and located in predicted epitope peptide, revealing that the pig's immunity may be a reason those sites are undergoing highly positive selection.


Assuntos
Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Suínos , Animais , Circovirus/genética , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Cidades , Doenças dos Suínos/epidemiologia , Filogenia , China/epidemiologia
12.
Appl Opt ; 61(29): 8671-8677, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256000

RESUMO

The pollution caused by the chemical cleaning of polymer coatings when recycling printing screens can be alleviated through laser cleaning. The interaction mechanism between the laser beam and polymer coating is studied, a laser ablation threshold model of the cross-linked polymer is constructed, and principles of laser bonding and photoionization are discussed. When the laser energy density is 7.8J/cm2, the laser pulse width and action energy influence the characterization after ablation. When the deposition energy is >1.2J/cm2, the polymer material undergoes carbonization. When the deposition energy is <0.8J/cm2, significant gasification and erosion are caused by the thermal decomposition of the resin. The findings provide a theoretical basis for research and reference for experiments and industrial applications.

13.
Entropy (Basel) ; 24(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36010708

RESUMO

In this paper, we propose a novel multi-user access in wireless optical communication based on the quantum detection of the coherent state. In this case, the coherent states are used as the signal carrier and a technique of quantum detection is applied to distinguish between signals from different users. To accomplish this task, two main quantum measurement methods are introduced; one is minimum error discrimination (MED), and the other is unambiguous state discrimination (USD). The theoretical derivation implies that the two methods can both distinguish between the signals from different users efficiently when the average photon number is large enough. Typically, the numerical result shows that in the two-user case, the channel capacity will approach the theoretical maximum limit when the average photon number is greater than 2.5 for MED and 5 for USD in the absence of noise. The MED gains more channel capacity than the USD at the same average photon number. However, the USD wins the error-correction scene with its free-error capability. Furthermore, the detection error probability and channel capacity for the USD with the thermal noise are examined. The result shows that increasing the signal average photon number can continue the USD's advantage of error-free detection even if in the presence of thermal noise. In addition, compared with non-orthogonal multiple access (NOMA), the bit error rate (BER) against signal-to-noise rate (SNR) performance of USD has been improved.

14.
Entropy (Basel) ; 25(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36673163

RESUMO

The higher-order structure of networks is a hot research topic in complex networks. It has received much attention because it is closely related to the functionality of networks, such as network transportation and propagation. For instance, recent studies have revealed that studying higher-order networks can explore hub structures in transportation networks and information dissemination units in neuronal networks. Therefore, the destruction of the connectivity of higher-order networks will cause significant damage to network functionalities. Meanwhile, previous works pointed out that the function of a complex network depends on the giant component of the original(low-order) network. Therefore, the network functionality will be influenced by both the low-order and its corresponding higher-order network. To study this issue, we build a network model of the interdependence of low-order and higher-order networks (we call it ILH). When some low-order network nodes fail, the low-order network's giant component shrinks, leading to changes in the structure of the higher-order network, which further affects the low-order network. This process occurs iteratively; the propagation of the failure can lead to an eventual network crash. We conducted experiments on different networks based on the percolation theory, and our network percolation results demonstrated a first-order phase transition feature. In particular, we found that an ILH is more fragile than the low-order network alone, and an ILH is more likely to be corrupted in the event of a random node failure.

15.
BMC Genomics ; 22(1): 376, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022814

RESUMO

BACKGROUND: The genus Rhododendron L. has been widely cultivated for hundreds of years around the world. Members of this genus are known for great ornamental and medicinal value. Owing to advances in sequencing technology, genomes and transcriptomes of members of the Rhododendron genus have been sequenced and published by various laboratories. With increasing amounts of omics data available, a centralized platform is necessary for effective storage, analysis, and integration of these large-scale datasets to ensure consistency, independence, and maintainability. RESULTS: Here, we report our development of the Rhododendron Plant Genome Database (RPGD; http://bioinfor.kib.ac.cn/RPGD/ ), which represents the first comprehensive database of Rhododendron genomics information. It includes large amounts of omics data, including genome sequence assemblies for R. delavayi, R. williamsianum, and R. simsii, gene expression profiles derived from public RNA-Seq data, functional annotations, gene families, transcription factor identification, gene homology, simple sequence repeats, and chloroplast genome. Additionally, many useful tools, including BLAST, JBrowse, Orthologous Groups, Genome Synteny Browser, Flanking Sequence Finder, Expression Heatmap, and Batch Download were integrated into the platform. CONCLUSIONS: RPGD is designed to be a comprehensive and helpful platform for all Rhododendron researchers. Believe that RPGD will be an indispensable hub for Rhododendron studies.


Assuntos
Rhododendron , Bases de Dados Genéticas , Genoma de Planta , Genômica , Humanos , Plantas , Rhododendron/genética , Transcriptoma
16.
Plant Biotechnol J ; 19(12): 2544-2560, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34375461

RESUMO

Azalea belongs to Rhododendron, which is one of the largest genera of flowering plants and is well known for the diversity and beauty in its more than 1000 woody species. Rhododendron contains two distinct groups: the most high-altitude and a few low-altitude species; however, the former group is difficult to be domesticated for urban landscaping, and their evolution and adaptation are little known. Rhododendron ovatum has broad adaptation in low-altitude regions but possesses evergreen characteristics like high-altitude species, and it has floral fragrance that is deficient in most cultivars. Here we report the chromosome-level genome assembly of R. ovatum, which has a total length of 549 Mb with scaffold N50 of 41 Mb and contains 41 264 predicted genes. Genomic micro-evolutionary analysis of R. ovatum in comparison with two high-altitude Rhododendron species indicated that the expansion genes in R. ovatum were significantly enriched in defence responses, which may account for its adaptability in low altitudes. The R. ovatum genome contains much more terpene synthase genes (TPSs) compared with the species that lost floral fragrance. The subfamily b members of TPS are involved in the synthesis of sesquiterpenes as well as monoterpenes and play a major role in flora scent biosynthesis and defence responses. Tandem duplication is the primary force driving expansion of defence-responsive genes for extensive adaptability to the low-altitude environments. The R. ovatum genome provides insights into low-altitude adaptation and gain or loss of floral fragrance for Rhododendron species, which are valuable for alpine plant domestication and floral scent breeding.


Assuntos
Rhododendron , Altitude , Flores/genética , Odorantes , Filogenia , Melhoramento Vegetal , Rhododendron/genética
17.
Opt Express ; 29(7): 11021-11036, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820223

RESUMO

Superconducting nanowire single-photon detectors (SNSPDs) have attracted remarkable interest for visible and near-infrared single-photon detection due to their outstanding performance. However, conventional SNSPDs are generally used as binary photon-counting detectors. Another important characteristic of light, i.e., polarization, which can provide additional information of the object, has not been resolved using the standalone SNSPD. In this work, we present a first prototype of the polarimeter based on a four-pixel superconducting nanowire array, capable of resolving the polarization state of linearly-polarized light at the single-photon level. The detector array design is based on a division of focal plane configuration in which the orientation of each nanowire division (pixel) is offset by 45°. Each single nanowire pixel operates as a combination of a photon detector and almost linear polarization filter, with an average polarization extinction ratio of ∼10. The total system detection efficiency of the array is ∼1% at a total dark count rate of 680 cps, with a timing jitter of 126 ps, when the detector array is free-space coupled and illuminated with 1550-nm photons. The mean errors of the measured angle of polarization and degree of linear polarization were about -3° and 0.12, respectively. Furthermore, we successfully demonstrated polarization imaging at low-light level using the proposed detector. Our results pave the way for the development of a single-photon sensitive, fast, and large-scale integrated polarization polarimeter or imager. Such detector may find promising application in photon-starved polarization resolving and imaging with high spatial and temporal resolution.

18.
Opt Lett ; 46(5): 1049-1052, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649654

RESUMO

We report a compact, scalable, and high-performance superconducting nanowire single-photon detector (SNSPD) array by using a multichannel optical fiber array-coupled configuration. For single pixels with an active area of 18 µm in diameter and illuminated at the telecom wavelength of 1550 nm, we achieved a pixel yield of 13/16 on one chip, an average system detection efficiency of 69% at a dark count rate of 160 cps, a minimum timing jitter of 74 ps, and a maximum count rate of ∼40Mcps. The optical crosstalk coefficient between adjacent channels is better than -60dB. The performance of the fiber array-coupled detectors is comparable with a standalone detector coupled to a single fiber. Our method is promising for the development of scalable, high-performance, and high-yield SNSPDs.

19.
Opt Express ; 28(18): 25716-25722, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32906856

RESUMO

Microfluidic chips have gradually become a focus of scientific research. However, the fabrication of key functional components in microfluidic chips is always limited by the existing processing methods. The microfluidic chip is difficult to be three-dimensional (3D) and integrated. In response to the key problems of 3D integrated microfluidic chip fabrication, this paper presents a hybrid method for fabricating a microfluidic chip integrated 3D microchannels and metal microstructures by femtosecond laser wet etch technology and liquid metal injection. The integrated microfluidic chip fabricated by this method is expected to be applied to the core reaction unit of integrated PCR devices.

20.
Ecotoxicol Environ Saf ; 205: 111362, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979807

RESUMO

Combined antibiotic and heavy metal pollution has generated considerable concern. Constructed wetlands (CWs) have been shown to efficiently remove pollutants; however, the microbial community responses to combined pollutants remain enigmatic. In this study, seven microcosm CWs were planted with Myriophyllum aquaticum, spiked with tetracyclines (TCs) (300-30,000 µg/L), alone or with Cu(II), to investigate the response of plant-associated microbial communities. TCs and the Cu/TC ratio greatly affected the performance of CWs. Tetracyclines led to higher microbial diversity, evenness and richness, while UniFrac distances and principal coordinate (PCO) and redundancy analyses revealed that the co-presence of TCs and Cu(II) led to variations in bacterial communities. Proteobacteria, Cyanobacteria and Bacteroidetes were the dominant microbial phyla and Cloacibacterium, Hydrogenophaga, Rheinheimera and Denitratisoma accounted for 6.2-21.0% of all genera. Therefore, the co-occurrence of heavy metals should be considered when judging the removal potential of TCs in phytoremediation.


Assuntos
Antibacterianos/toxicidade , Saxifragales/fisiologia , Tetraciclinas/toxicidade , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Biodegradação Ambiental , Cianobactérias , Compostos Heterocíclicos , Metais Pesados , Microbiota , Proteobactérias , Poluentes Químicos da Água/análise
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