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1.
Integr Comp Biol ; 64(3): 661-673, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-38901961

RESUMO

Tails play essential roles in functions related to locomotor stability and maneuverability among terrestrial and arboreal animals. In kangaroo rats, bipedal hopping rodents, tails are used as effective inertial appendages for stability in hopping, but also facilitate stability and maneuverability during predator escape leaps. The complexity of tail functionality shows great potential for bio-inspiration and robotic device design, as maneuvering is accomplished by a long and light-weight inertial appendage. To (1) further understand the mechanics of how kangaroo rats use their tails during aerial maneuvers and (2) explore if we can achieve this behavior with a simplified tail-like appendage (i.e., template), we combined quantified animal observations, computational simulations, and experiments with a two degrees of freedom (2-DoF) tailed robot. We used video data from free-ranging kangaroo rats escaping from a simulated predator and analyzed body and tail motion for the airborne phase. To explain tail contributions to body orientation (i.e., spatial reorientation), we built a mid-air kangaroo rat computational model and demonstrated that the three-dimensional body orientation of the model can be controlled by a simplified 2-DoF tail with a nonlinear control strategy. Resulting simulated trajectories show movement patterns similar to those observed in kangaroo rats. Our robot experiments show that a lightweight tail can generate a large yaw displacement and stabilize pitch and roll angles to zero simultaneously. Our work contributes to better understanding of the form-function relationship of the kangaroo rat tail and lays out an important foundation for bio-inspiration in robotic devices that have lightweight tail-like appendages for mid-air maneuvering.


Assuntos
Simulação por Computador , Dipodomys , Robótica , Cauda , Animais , Cauda/fisiologia , Dipodomys/fisiologia , Fenômenos Biomecânicos , Modelos Biológicos , Locomoção/fisiologia
2.
Appl Opt ; 63(10): 2608-2613, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568543

RESUMO

High-quality single-photon sources are crucial for the development of simple quantum devices. Quantum communication stands at the forefront of cutting-edge technologies, promising unprecedented levels of security and efficiency. A cornerstone of this revolutionary field is the development of high-speed single-photon sources, which play a pivotal role in quantum key distribution and other quantum communication protocols. In this context, the concept of space multimode emerges as a promising avenue to propel the capabilities of single-photon sources to new heights. We have spatial multiplexing technology to develop single-photon sources that deliver high-speed heralded single photons in the Duan-Lukin-Cirac-Zoller (DLCZ) scheme. We propose a spatial multiplexing single-photon source scheme based on the DLCZ. Compared to a single spatial mode, by adding six spatial modes through spatial multiplexing, the single-photon generation rate increases 4.3 times. And the second-order correlation function of single photons is less than 0.5. We show that expanding the spatial degrees of freedom of the quantum storage scheme based on DLCZ does not affect the single-photon properties. The generation rate of the single photon can be significantly increased through spatial multiplexing with a feedback circuit. Our approach offers a promising path to creating a high-speed photon source based on a spatial multimode scheme.

3.
Sensors (Basel) ; 23(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37765887

RESUMO

The minimum vertex cover (MVC) problem is a canonical NP-hard combinatorial optimization problem aiming to find the smallest set of vertices such that every edge has at least one endpoint in the set. This problem has extensive applications in cybersecurity, scheduling, and monitoring link failures in wireless sensor networks (WSNs). Numerous local search algorithms have been proposed to obtain "good" vertex coverage. However, due to the NP-hard nature, it is challenging to efficiently solve the MVC problem, especially on large graphs. In this paper, we propose an efficient local search algorithm for MVC called TIVC, which is based on two main ideas: a 3-improvements (TI) framework with a tiny perturbation and edge selection strategy. We conducted experiments on real-world large instances of a massive graph benchmark. Compared with three state-of-the-art MVC algorithms, TIVC shows superior performance in accuracy and possesses a remarkable ability to identify significantly smaller vertex covers on many graphs.

4.
Eur J Oral Sci ; 131(5-6): e12945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37461146

RESUMO

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a unique member of the neurotrophic factor family residing in the endoplasmic reticulum, where it functions as a stress response protein maintaining endoplasmic reticulum homeostasis, in addition to being secreted extracellularly as a neurotrophic factor to bind with receptors to initiate intracellular signal transduction pathways. Interestingly, MANF has shown an important protective role in the inflammatory response of many diseases. In neural stem cells, pancreatic ß cells, and retinal cells, MANF can inhibit the inflammatory response, modulate the immune response, and promote tissue repair. However, the role of MANF in the periodontal inflammatory response remains unclear. In the present study, we used lipopolysaccharide (LPS) from Porphyromonas gingivalis (Pg) to establish a Pg-LPS-stimulated periodontal inflammatory model in human gingival fibroblasts cells (HGF-1) to investigate the role of MANF in vitro. We found that MANF could inhibit pro-inflammatory cytokine secretion, alleviate the endoplasmic reticulum stress response, promote cell survival, and inhibit cell apoptosis. Therefore, MANF might be a novel promising target for the treatment of periodontitis.


Assuntos
Astrócitos , Lipopolissacarídeos , Humanos , Astrócitos/metabolismo , Lipopolissacarídeos/metabolismo , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/farmacologia , Neurônios , Estresse do Retículo Endoplasmático
5.
Nanomaterials (Basel) ; 12(23)2022 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-36500927

RESUMO

Combining steady-state photoluminescence and transient absorption (TA) spectroscopy, we have investigated the photoinduced charge transfer dynamics between lead-free Mn-doped Cs2NaIn0.75Bi0.25Cl6 double perovskite (DP) nanocrystals (NCs) and conjugated poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV). Upon ultraviolet-A excitation, the photoinduced absorption feature of DP NCs/MDMO-PPV nanocomposites disappeared, and the stimulated emission weakened in the TA spectrum. This was due to charge transfer from the MDMO-PPV polymers to DP NCs. Upon a higher photon-energy ultraviolet-C excitation, stimulated emission and photoinduced absorption features vanished, indicating there existed a reversible charge transfer from DP NCs to MDMO-PPV polymers. Reversible charge transfer of Mn-doped DP NCs/MDMO-PPV nanocomposites was tuned by varying the excitation photon-energy. The manipulation of reversible charge transfer dynamics in the perovskite-polymer nanocomposites opens a new avenue for optical and optoelectronic applications.

6.
Bull Cancer ; 109(9): 886-894, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35788271

RESUMO

Epithelial-mesenchymal transition (EMT) is a key initial step in the recurrence and metastasis of tongue squamous cell carcinoma (TSCC). Hyperthermia (HT) may reduce the rate of postoperative recurrence and distant metastasis by reversing the process of EMT of tumor cells, but the molecular mechanism is unclear. This study aims to investigate the role of inhibitor of differentiation/DNA binding-1 (Id-1) in HT mediated reversal of EMT of TSCC cells, and to provide a new approach for the treatment of TSCC using therapeutic gene targeting. After the combination of RNA interference with Id-1 and HT, the morphology of TSCC cells changed from spindle-like to pebble-like, and the arrangement of cells changed from loose and disorderly to compact and orderly. The silencing of Id-1 gene enhances the efficacy of HT by affecting the expression of EMT markers in TSCC cells. This study suggests that the Id-1 gene in TSCC cells can regulate transforming growth factor-beta 1, thereby affecting the expression of EMT markers, to achieve the effect of reducing HT.


Assuntos
Carcinoma de Células Escamosas , Hipertermia Induzida , Neoplasias da Língua , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Língua/metabolismo , Língua/patologia , Neoplasias da Língua/genética , Neoplasias da Língua/metabolismo , Neoplasias da Língua/terapia
7.
Opt Express ; 30(2): 2792-2802, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209412

RESUMO

Controls of waveforms (pulse durations) of single photons are important tasks for effectively interconnecting disparate atomic memories in hybrid quantum networks. So far, the waveform control of a single photon that is entangled with an atomic memory remains unexplored. Here, we demonstrated control of waveform length of the photon that is entangled with an atomic spin-wave memory by varying light-atom interaction time in cold atoms. The Bell parameter S as a function of the duration of photon pulse is measured, which shows that violations of Bell inequality can be achieved for the photon pulse in the duration range from 40 ns to 50 µs, where, S = 2.64 ± 0.02 and S = 2.26 ± 0.05 for the 40-ns and 50-µs durations, respectively. The measured results show that S parameter decreases with the increase in the pulse duration. We confirm that the increase in photon noise probability per pulse with the pulse-duration is responsible for the S decrease.

8.
Cell Death Discov ; 7(1): 227, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465721

RESUMO

Autophagy has a complex dual role in tumor survival or cell death owning to that is an evolutionarily conserved catabolic mechanism and provides the cells with a sustainable source of biomolecules and energy for the maintenance of homeostasis under stressful conditions such as tumor microenvironment. Hyperthermia is a rapidly growing field in cancer therapy and many advances have been made in understanding and applying the mechanisms of hyperthermia. The shallow oral and maxillofacial position and its abundant blood supply are favorable for the use of hyperthermia. However, the relationship between hyperthermia and autophagy has not been examined of oral squamous cell carcinoma (OSCC) in the tumor hypoxia microenvironment. Here, the expression level of autophagy relative genes is examined to explore autophagy effect on the responses of hyperthermia, hypoxia, and innutrition tumor microenvironment. It is founded that hyperthermia and hypoxia cause autophagy in starvation conditions; further, in hypoxia and innutrition tumor microenvironment, hyperthermia combines YC-1 and 3-MA could inhibit HIF-1α/BNIP3/Beclin1 signal pathway and decrease the secretion of HMGB1; moreover, the cell apoptosis rate increases with an inhibited of cell migration capacity. Thus, the present study demonstrated that combined use of YC-1 and 3-MA might increase the death of tumor cells in physiological and hyperthermic conditions, which could be relevant with the inhibition of autophagy in OSCC tumor cells under hypoxia microenvironment in vitro, which offers new insight into the therapy of OSCC and its application in treating others study carcinomas.

9.
Microb Pathog ; 160: 105192, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34534642

RESUMO

BACKGROUND: Variations in the oral microbiota have been significantly correlated with the progress of autoimmune diseases, such as immunoglobulin A nephropathy and Henoch-Schönlein purpura (HSP). However, there is no report outlining the character of tongue coating microbiota variations in children with Henoch-Schönlein purpura nephritis (HSPN). METHOD: A total of 20 children with HSPN and 14 healthy controls were recruited for this research. Tongue coating samples of two groups were collected for 16S rRNA gene sequencing. The diversity, principal component analysis (PCA), nonmetric multidimensional scaling (NMDS), partial least squares discriminant analysis (PLS-DA), and linear discriminant analysis (LDA) effect size (LEfSe) were performed. Microbial function was assessed using the PICRUST. RESULTS: The ACE and Chao indices were greatly lower in the HSPN group than in the HG (P = 0.001). The Shannon and Simpson indices were dramatically reduced in children with HSPN compared with those in the healthy controls (P = 0.005). Bacteroidales, Selenomonadales, Lactobacillales, Fusobacteriales, Neisseriales, and Actinomycetales composed more than 80% of all sequences, while Bacteroidales was the most generous order in both groups. PCA, NMDS and PLS-DA showed a marked difference between the control and HSPN groups. LEfSe analysis showed alteration of tongue coating microbiota in the HSPN group. There were 30 metabolic functions significantly differed between the two groups. CONCLUSIONS: Children with HSPN have substantially various tongue coating microbiota compared to healthy controls. Even though this research does not indicate causality, it is beneficial to enhance the possibility for coming microbial-based treatments to enhance the clinical effects of HSPN in children.


Assuntos
Vasculite por IgA , Microbiota , Nefrite , Criança , Humanos , RNA Ribossômico 16S/genética , Língua
10.
Immunopharmacol Immunotoxicol ; 43(6): 666-673, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34519594

RESUMO

The pathogenic roles for B cells in autoimmunity include produce pathogenic autoantibodies and modulate immune responses via the production of cytokines and chemokines. The B lymphocyte stimulator BLyS (also known as B-cell-activating factor, BAFF) and APRIL (a proliferation-inducing ligand) are critical factors in the maintenance of the B-cell pool and humoral immunity, namely BLyS modulates the differentiation and maturation of immature B cell, while APRIL modulates the function and survival of long-lived plasma cell, which plays a prominent role in the pathogenesis of autoimmune diseases. Telitacicept is a novel recombinant fusion protein of both the ligand-binding domain of the TACI receptor and the Fc component of human IgG and which is a BLyS/APRIL dual inhibitor. Moreover, telitacicept was developed by Remegen Co., Ltd. in China and is approved to treat systemic lupus erythematosus in China. We review the rationale, clinical evidence, and future perspectives of telitacicept for the treatment of autoimmune disease.HighlightThe B lymphocyte stimulator BLyS (also known as B-cell-activating factor, BAFF) and APRIL (a proliferation-inducing ligand), members of tumor necrosis factor (TNF) family, and which are critical factors in the maintenance of the B-cell pool and humoral immunity.BAFF and APRIL are implicated in the pathogenesis of several human autoimmune diseases with autoreactive B-cell involvement, and targeting both is beneficial for the treatment of autoimmune diseases.Telitacicept is a novel recombinant fusion protein of both the ligand-binding domain of the TACI receptor and the Fc component of human IgG, as a BLyS/APRIL dual inhibitor and which has been approved by National Medical Products Administration (MNPA) for the treatment of patients with SLE in China.With more clinical trials underway, telitacicept may also be approved for the treatment of other autoimmune diseases in the future.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Fator Ativador de Células B/antagonistas & inibidores , Imunossupressores/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Animais , Doenças Autoimunes/imunologia , Fator Ativador de Células B/imunologia , Ensaios Clínicos como Assunto/métodos , Humanos , Imunossupressores/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia
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