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1.
Opt Lett ; 49(3): 415-417, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300033

RESUMO

We present a corrigendum to our Letter [Opt. Lett.48, 5699 (2023)10.1364/OL.505761]. In section 3 of the original supplementary material, the absolute value is incorrectly taken in resolving the Kubo formula for describing the conductivity of graphene. Because this is a mistake with the conductivity of graphene, the coupling of the original structure is broken when the correct result is inserted into the code of the transfer matrix. So, the structure of the arithmetic logic unit (ALU), characteristic frequency point, and phase control have been modified accordingly. However, the ultimate function and the conclusion of this work remain unchanged.

2.
Phys Chem Chem Phys ; 26(5): 4447-4454, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38240154

RESUMO

A one-dimensional optical biosensing metastructure (OBM) with graphene layers is presented in this paper. It is realized by coherent perfect absorption (CPA) and operates in the transverse electric mode. It shows a strong linear fitting relationship between the refractive index (RI) of the analysis layer and the frequency corresponding to the absorption peak, and the R-square is up to 1. Additionally, based on the principle of CPA, the OBM can realize the function of multiple cancer cell detection by adjusting the detection range by controlling the phase difference of coherent electromagnetic waves. Its detection ranges are 1.34-1.355 and 1.658-1.662. Thanks to its high-quality factor, great figure of merit, and low detection limit, whose best values are, respectively, 6.9 × 104, 1.2 × 104 RIU-1, and 3.6 × 10-6 RIU, the detection of weak changes in the RI of a cancer cell is possible. Additionally, its sensitivity can reach 26.57 THz RIU-1. This OBM based on CPA has major implications for advancing the study and investigation into the application of CPA. It also provides a simple and efficient approach to distinguish cancer cells and may be widely used in the biomedical field.


Assuntos
Grafite , Neoplasias , Humanos , Eletricidade , Neoplasias/diagnóstico
3.
Opt Lett ; 48(21): 5699-5702, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910737

RESUMO

An arithmetic logic unit (ALU) based on the metastructure (MS) with coherent absorption (CA) is proposed in this Letter. The ALU can perform AND and exclusive OR logical operations at the same frequency point. So it can be regarded as an optical half-adder. By controlling the chemical potential of graphene and the phase difference of coherent electromagnetic waves (EWs), two different binary numbers are input into the ALU. The dynamic absorption peaks, which are generated based on the CA, output the outcomes of the carry-digit bit and non-carry sum bit. This ALU can be used in the field of optical processing and encryption, such as processing hamming code. This given ALU based on the MS with CA has major implications for advancing the study and investigation into the application of CA. Furthermore, it also provides a new, to the best of our knowledge, idea for the study of MS with logical operation.

4.
Sensors (Basel) ; 23(10)2023 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-37430663

RESUMO

In this paper, a Janus metastructure sensor (JMS) based on the photonic spin Hall effect (PSHE), which can detect multiple physical quantities, is proposed. The Janus property is derived from the fact that the asymmetric arrangement of different dielectrics breaks the structure parity. Hence, the metastructure is endowed with different detection performances for physical quantities on multiple scales, broadening the range and improving the accuracy of the detection. When electromagnetic waves (EWs) are incident from the forward scale of the JMS, the refractive index, thickness, and incidence angle can be detected by locking the angle corresponding to the PSHE displacement peak that is enhanced by the graphene. The relevant detection ranges are 2~2.4, 2~2.35 µm, and 27°~47°, with sensitivities (S) of 81.35°/RIU, 64.84°/µm, and 0.02238 THz/°, respectively. Under the condition that EWs incident into the JMS from the backward direction, the JMS can also detect the same physical quantities with different sensing properties, such as S of 99.3°/RIU, 70.07°/µm, and 0.02348 THz/° in corresponding detection ranges of 2~2.09, 1.85~2.02 µm, and 20°~40°. This novel multifunctional JMS is a supplement to the traditional single-function sensor and has a certain prospect in the field of multiscenario applications.

5.
Opt Lett ; 48(10): 2627-2630, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37186725

RESUMO

To date there have been many studies on multi-channel absorbers for conventional photonic crystals (PCs). However, the number of absorption channels is small and uncontrollable, which cannot satisfy applications such as multispectral or quantitative narrowband selective filters. To address these issues, a tunable and controllable multi-channel time-comb absorber (TCA) based on continuous photonic time crystals (PTCs), is theoretically proposed. Compared with conventional PCs with fixed refractive index (RI), this system forms a stronger local electric field enhancement in the TCA by absorbing externally modulated energy, resulting in sharp multi-channel absorption peaks (APs). Tunability can be achieved by adjusting the RI, angle, and time period unit (T) of the PTCs. Diversified tunable methods allow the TCA to have more potential applications. In addition, changing T can adjust the number of multi-channels. More importantly, changing the primary term coefficient of n1(t) of PTC1 can control the number of time-comb absorption peaks (TCAPs) in multi-channels within a certain range, and the mathematical relationship between the coefficients and the number of multiple channels is summarized. This will have potential applications in the design of quantitative narrowband selective filters, thermal radiation detectors, optical detection instruments, etc.

6.
Theriogenology ; 197: 232-239, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36525862

RESUMO

In order to explore the differential metabolites between fresh and frozen-thawed semen of Guanzhong dairy goats, semen samples were collected by artificial vagina method, and divided into fresh and frozen-thawed semen groups, with six replicates in each group. Liquid Chromatography-mass spectrometry (LC-MS) technology was used to detect semen metabolites in both groups. The metabolites were analyzed and identified by the combination of multidimensional statistical analysis, namely principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA) and univariate statistical analysis, Differential metabolites were identified according to One-step Solution for Identification of Small Molecules in Metabolomics Studies (OSI/SMMS) combined with Human Metabolome Database (HMDB), Lipidmaps and Metlin and the metabolic pathways of different metabolites were enriched and analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The results showed that a total of 53 differential metabolites were detected in fresh and frozen-thawed semen groups, of which 10 metabolites were significantly up-regulated (P < 0.05) and 43 were significantly down-regulated (P < 0.05). Most of the metabolites belonged to lipids and lipid-like molecules, organic acids and their derivatives, organic oxygen compounds, etc. According to the functional enrichment analysis of the top twenty differential metabolites in the KEGG database, significant changes occurred in linoleic acid metabolism pathway out of total eleven pathways observed. These differential metabolites can be used as metabolic markers of sperm cryo-injury in dairy goats.


Assuntos
Metabolômica , Sêmen , Feminino , Masculino , Humanos , Animais , Congelamento , Metabolômica/métodos , Metaboloma , Cabras
7.
Theriogenology ; 189: 113-117, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35751978

RESUMO

There are phospholipase and yolk agglutinase in the seminal plasma of dairy goat. The existence of these enzymes will hydrolyze lecithin in yolk into lysophosphatides and cause the change of pH value of diluent, resulting in toxic and side effects on sperm. In order to explore the effect of bovine seminal plasma replacing different doses of dairy goat seminal plasma (0%, 25%, 50%, 100%) on semen freezing quality of Guanzhong dairy goat, we used computer-aided sperm analysis (CASA) system, specific fluorescent probe detection technology, hypo osmotic swelling test (HOST), oxidation index determination and in vivo fertilization verification test to study the semen cryopreservation of Guanzhong dairy goat. The results showed that if we used bovine seminal plasma instead of 100% dairy goat seminal plasma, the sperm motility, plasma membrane functionality and acrosome integrity rate were the highest after thawing, reaching 67.04%, 38.12% and 68.83% respectively, which was significantly higher than that of other groups (P < 0.05); In terms of oxidation indexes, the values of SOD and GSH-PX in sperm of dairy goats were 199.78 U/mL and 133.55 U/L, respectively, which were significantly higher than those in other groups (P < 0.05), and the values of ROS and MDA were 397.58 U/mL and 5.16 nmol/L, respectively, which were significantly lower than those in other groups (P < 0.05); The results of artificial insemination also showed that using bovine seminal plasma instead of 100% of dairy goat seminal plasma could significantly improve the fertilization ability of sperm. The quality of frozen Guanzhong dairy goat sperm can be improved by using bovine seminal plasma instead of dairy goat seminal plasma and using bovine diluent.


Assuntos
Preservação do Sêmen , Animais , Bovinos , Criopreservação/métodos , Criopreservação/veterinária , Cabras , Masculino , Sêmen , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
8.
Gen Comp Endocrinol ; 321-322: 114027, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35300988

RESUMO

Paired-like homeodomain transcription factor 2 (PITX2), a major driver of multiple tissue development, is a transcription factor that regulates gene expression in organisms. However, it is unknown if PITX2 regulates goat granulosa cell (GC) steroidogenesis. Therefore, we investigated the role and mechanism of PITX2 in GC steroidogenesis. In our study, PITX2 significantly facilitated the secretion level of estrogen and progesterone through increasing CYP11A1, CYP19A1, and STAR mRNA and protein expressions in GCs. Furthermore, PITX2 participated in the WNT pathway, enhancing the production of E2 and P4 in GCs. PITX2 in GCs increased the DVL-1 and CTNNB1 expression, involved in the WNT/ß-catenin signaling pathway related to steroidogenesis. Moreover, GC steroidogenesis-related gene translation was decreased by CTNNB1-siRNA but enhanced when transfected with PITX2. PITX2 regulates secretion of E2 and P4 from GCs via the WNT/ß-catenin pathway and alters GC proliferation and steroidogenesis. These findings will help understand the role of PITX2 in goat ovarian follicular development and oocyte maturation.


Assuntos
Via de Sinalização Wnt , beta Catenina , Animais , Feminino , Cabras/metabolismo , Células da Granulosa/metabolismo , Fatores de Transcrição/genética , beta Catenina/genética , beta Catenina/metabolismo
9.
Sensors (Basel) ; 23(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36616865

RESUMO

The precise three-dimensional measurement of fuel nozzles is of great significance to assess the manufacturing accuracy and improve the spray and atomization performance. This paper proposes an improved fast shape from focus (SFF) method for three-dimensional measurement of key features of fuel nozzles. In order to ensure the measurement accuracy and efficiency of the SFF, the dispersion of the measured points from a standard flat plane was used to select the optimal combination of the focus measure operator, window size and sampling step size. In addition, an approximate method for the focus measure interval is proposed to improve the measurement efficiency, which uses the peak region of the central pixel to replace the peak region of other pixels. The results show that the proposed method decreased the average computation time of the focus measure by 79.19% for the cone section and by 38.30% for the swirl slot. Compared with a reference laser scanning microscope, the measurement error in length is within 10 µm and the error in angle is within a maximum 0.15°.

10.
Front Vet Sci ; 8: 771440, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869742

RESUMO

In the process of cryopreservation of dairy goat semen, it will face many threats such as oxidative damage, which will affect the motility and plasma membrane function of sperm. As an endogenous antioxidant in animals, glutathione (GSH) can significantly improve the quality of thawed sperm when added to the frozen diluent of semen of pigs and cattle. In this study, different concentration gradients of GSH [0 mmol/L (control), 1, 2, 3, 4 mmol/L] were added to the frozen diluent of Guanzhong dairy goat semen. By detecting the sperm motility parameters, acrosome intact rate and plasma membrane intact rate after thawing, the effect of GSH on the cryopreservation of dairy goat semen was explored. Sperm motility parameters were measured with the computer-aided sperm analysis (CASA) system (total power, TM; forward power, PM; linearity, LIN; average path speed, VAP; straight line speed, VSL; curve speed, VCL; beat cross frequency, BCF). The sperm acrosome integrity rate after thawing was detected by a specific fluorescent probe (isothiocyanate-labeled peanut agglutinin, FITC-PNA), and the sperm plasma membrane integrity rate after thawing was detected by the hypotonic sperm swelling (HOST) method. Reactive oxygen species (ROS) kit, malondialdehyde (MDA) kit, superoxide dismutase (SOD) kit, glutathione peroxidase (GSH-PX) kit were used to detect various antioxidant indicators of thawed sperm. in vitro fertilization experiment was used to verify the effect of adding glutathione on sperm fertilization and embryo development. The results showed that when the concentration of glutathione was 2 mmol/l, the sperm viability, plasma membrane intact rate, and acrosome intact rate were the highest after thawing, reaching 62.14, 37.62, and 70.87% respectively, and they were all significantly higher. In terms of antioxidant indexes; the values of SOD and GSH-PX were 212.60 U/ml and 125.04 U/L, respectively, which were significantly higher than those of the control group; The values of ROS and MDA were 363.05 U/ml and 7.02 nmol/L, respectively, which were significantly lower than the control group. The addition of 2 mmol/L glutathione significantly improves the fertilization ability of sperm. In short, adding 2 mmol/l glutathione to the semen diluent can improve the quality of frozen Guanzhong dairy goat sperm.

11.
Nanoscale Adv ; 3(9): 2475-2480, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-36134169

RESUMO

Electronic textiles (e-textiles) typically comprise fabric substrates with electronic components capable of heating, sensing, lighting and data storage. In this work, we rationally designed and fabricated anisotropic light/thermal emitting e-textiles with great mechanical stability based on a sandwich-structured tri-electrode device. By coating silver nanowire network/thermal insulation bilayer on fabrics, an anisotropic thermal emitter can be realized for smart heat management. By further covering the emissive film and the top electrode on the bilayer, light emitters with desirable patterns and colors are extracted from the top surface via an alternative current derived electroluminescence. Both the light and thermal emitting functions can be operated simultaneously or separately. Particularly, our textiles exhibit reliable heating and lighting performance in water, revealing excellent waterproof feature and washing stability.

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