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1.
Front Neurosci ; 15: 755709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744616

RESUMO

Objective: Intermittent theta burst stimulation (iTBS) is a special form of repetitive transcranial magnetic stimulation (rTMS), which effectively increases cortical excitability and has been widely used as a neural modulation approach in stroke rehabilitation. As effects of iTBS are typically investigated by motor evoked potentials, how iTBS influences functional brain network following stroke remains unclear. Resting-state electroencephalography (EEG) has been suggested to be a sensitive measure for evaluating effects of rTMS on brain functional activity and network. Here, we used resting-state EEG to investigate the effects of iTBS on functional brain network in stroke survivors. Methods: We studied thirty stroke survivors (age: 63.1 ± 12.1 years; chronicity: 4.0 ± 3.8 months; UE FMA: 26.6 ± 19.4/66) with upper limb motor dysfunction. Stroke survivors were randomly divided into two groups receiving either Active or Sham iTBS over the ipsilesional primary motor cortex. Resting-state EEG was recorded at baseline and immediately after iTBS to assess the effects of iTBS on functional brain network. Results: Delta and theta bands interhemispheric functional connectivity were significantly increased after Active iTBS (P = 0.038 and 0.011, respectively), but were not significantly changed after Sham iTBS (P = 0.327 and 0.342, respectively). Delta and beta bands global efficiency were also significantly increased after Active iTBS (P = 0.013 and 0.0003, respectively), but not after Sham iTBS (P = 0.586 and 0.954, respectively). Conclusion: This is the first study that used EEG to investigate the acute neuroplastic changes after iTBS following stroke. Our findings for the first time provide evidence that iTBS modulates brain network functioning in stroke survivors. Acute increase in interhemispheric functional connectivity and global efficiency after iTBS suggest that iTBS has the potential to normalize brain network functioning following stroke, which can be utilized in stroke rehabilitation.

2.
Photoacoustics ; 21: 100224, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34745880

RESUMO

Photoacoustic transmitter represents a promising substitute for conventional piezoelectric counterparts. However, lack of easy and effective method for dynamically manipulating the focused acoustic field is a common and tricky problem faced by current photoacoustic technology. In this paper, a new strategy for constructing focus tunable photoacoustic transmitter is proposed. Different from existed prevailing device architecture, a sandwich like photoacoustic conversion layer is innovatively designed into a suspending elastic membrane with clamped boundary and it can be deformed using integrated pneumatic actuator. Owing to the membrane deflection property, concave spherical contours with variable radius of curvature can be obtained. Considering the shape determined sound emission characteristic, continuous tuning on the axial focusing length of the acoustic field has been successfully demonstrated in the photoacoustic transmitter for the first time. Besides, acoustic signal with significantly improved negative pressure has also been achieved especially at the focus, bringing additional advantage for applications.

3.
Brain Behav ; : e2416, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34775689

RESUMO

PURPOSE: This study investigated the clinical epidemiological characteristics of nitrous oxide (N2 O) abusers in a hospital in China, which have not been systematically reported. METHODS: The characteristics of patients abusing N2 O who were examined and treated at the Affiliated Hospital of Xuzhou Medical University from January 2017 to December 2020 were analyzed. RESULTS: A total of 61 patients (average age: 21.7 ± 3.2 years; 42 male and 19 female) were enrolled; 60.7% of the patients had an education level of high school or lower, and most (59.0%) had no stable occupation. The mean exposure time was 8.5 ± 7.7 months (range: 1-36 months). Only 52.5% of the abusers reported the physician of the relevant exposure history at the first time of visiting the doctor. The main clinical type was mixed (49.2%). The most common clinical manifestation was distal limb numbness (80.3%). The most frequent outcome was peripheral neuropathy (59%) and subacute combined degeneration (36%). Serum homocysteine level was elevated in 67.5% (27/40) of the patients, while 44.4% (20/45) showed reduced vitamin B12. Note that 61% (22/36) showed abnormal signals in the posterior or lateral funiculus of the spinal cord, and 97% (31/32) of the patients showed peripheral nerve damage by electromyography. In all cases, symptoms were alleviated after halting N2 O intake and receiving nutritional neurotherapy. CONCLUSIONS: N2 O abuse can lead to nervous system damage, especially peripheral nerve and spinal cord damage. A full understanding of its clinical epidemiological characteristics is helpful for clinicians to make a timely and clear diagnosis.

4.
Autophagy ; : 1-3, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34779709

RESUMO

ER-specific autophagy (reticulophagy) has emerged as a critical degradative route for misfolded secretory proteins. Our previous work showed that RTN3 (reticulon 3) drives reticulophagic clearance of disease-causing mutant prohormones. How RTN3, a protein residing on the cytosolic leaflet of the ER bilayer, recruits these lumenally-localized cargos has remained a mystery. To address this question, we used an unbiased proteomics approach to identify RTN3-interacting partners. We discovered that RTN3 recruits misfolded prohormones for lysosomal degradation through the ER transmembrane protein PGRMC1. RTN3 complexes with PGRMC1, which directly binds to misfolded prohormones via its distal ER lumenal domain. Cargos for the RTN3-PGRMC1 degradative axis include mutant POMC (proopiomelanocortin) and proinsulin, each of which oligomerizes in the ER during misfolding, entrapping their wild-type counterparts, leading to secretion defects. Although reticulophagy is thought to degrade large protein aggregates, PGRMC1 instead selectively recruits and promotes degradation of only small oligomers of the mutant prohormones. Of physiological importance, genetic or pharmacological inactivation of PGRMC1 in pancreatic ß-cells expressing both wild-type and mutant proinsulin impairs mutant proinsulin turnover and promotes trafficking of wild-type proinsulin. These findings pinpoint PGRMC1 as a possible intervention point for diseases caused by ER protein retention.

5.
Materials (Basel) ; 14(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34832402

RESUMO

In this work, a visible-light-driven BiOCl/Bi2WO6 photocatalyst was obtained via a facile hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), ultraviolet/visible light diffuse reflection spectroscopy (UV/Vis), and photocurrent (PC). BiOCl/Bi2WO6 was modified with (3-chloro-2-hydroxypropyl) trimethyl ammonium chloride to obtain the cationized BiOCl/Bi2WO6. Cotton fabric was pretreated with sodium hydroxide (NaOH) and sodium chloroacetate solution to obtain carboxymethylated cotton fabric, which was further reacted with cationized BiOCl/Bi2WO6 to achieve finished cotton fabric. The cotton fabrics were characterized by Fourier-transform infrared spectroscopy (FT-IR), XRD, SEM, and EDS. The photocatalytic activity of the BiOCl/Bi2WO6 photocatalyst and cotton fabrics was assessed by photocatalytic degradation of MB (methylene blue) solution under simulated visible light. The self-cleaning property of cotton fabrics was evaluated by removing MB solution and red-wine stains. Results revealed that the coated cotton fabrics exhibited appreciable photocatalytic and self-cleaning performance. In addition, anti-UV studies showed that the finished cotton fabrics had remarkable UV blocking properties in the UVA and UVB regions. Therefore, the finished cotton fabric with BiOCl/Bi2WO6 can provide a framework for the development of multifunctional textiles.

6.
Genome Biol ; 22(1): 282, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34607603

RESUMO

BACKGROUND: Zebrafish pigment cell differentiation provides an attractive model for studying cell fate progression as a neural crest progenitor engenders diverse cell types, including two morphologically distinct pigment cells: black melanophores and reflective iridophores. Nontrivial classical genetic and transcriptomic approaches have revealed essential molecular mechanisms and gene regulatory circuits that drive neural crest-derived cell fate decisions. However, how the epigenetic landscape contributes to pigment cell differentiation, especially in the context of iridophore cell fate, is poorly understood. RESULTS: We chart the global changes in the epigenetic landscape, including DNA methylation and chromatin accessibility, during neural crest differentiation into melanophores and iridophores to identify epigenetic determinants shaping cell type-specific gene expression. Motif enrichment in the epigenetically dynamic regions reveals putative transcription factors that might be responsible for driving pigment cell identity. Through this effort, in the relatively uncharacterized iridophores, we validate alx4a as a necessary and sufficient transcription factor for iridophore differentiation and present evidence on alx4a's potential regulatory role in guanine synthesis pathway. CONCLUSIONS: Pigment cell fate is marked by substantial DNA demethylation events coupled with dynamic chromatin accessibility to potentiate gene regulation through cis-regulatory control. Here, we provide a multi-omic resource for neural crest differentiation into melanophores and iridophores. This work led to the discovery and validation of iridophore-specific alx4a transcription factor.

7.
J Cosmet Dermatol ; 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34716978

RESUMO

BACKGROUND: Wound healing problem is one of the main complications after correction of chest wall deformity. Orthopedic flap tissue repair technique has a clear significance in non-healing wound and defect wound and provides a new choice for poor wound healing after orthopedic surgery of chest wall deformity. OBJECTIVE: To investigate, the application value of modified local rotary flap and latissimus dorsi myocutcutaneous flap in the treatment of poor wound healing after orthodontic treatment of chest wall deformity. METHOD: A retrospective analysis was performed on patients who admitted to our department from August 2012 to November 2019 due to non-healing incision after surgery for thoracic deformity. Skin flap was selected according to the size of the wound surface, and the effect of skin flap repair was observed. The clinical data of the included patients were recorded, and the preoperative and postoperative wound conditions were evaluated. RESULTS: This study included 13 patients with chest wall deformity who received plastic surgery tissue using flap technique for wound repair, 11 cases used modified local rotation skin flap, and 2 cases used modified latissimus dorsi myocutaneous flap. The mean age of the 13 patients was 18.54 ± 4.14 years old, the mean body mass index (BMI) was 17.02 ± 2.16 kg/m2 , and the mean preoperative nonunion time of the incision was 64.77 ± 93.01 days. Five patients had positive bacteria culture on the wound surface, including 3 cases of Staphylococcus aureus, 1 case of Pseudomonas aeruginosa, and 1 case of Staphylococcus epidermidis. All the 13 patients achieved primary grade A healing. CONCLUSION: The modified local rotary flap and latissimus dorsi musculocutaneous flap have a significant effect on the postoperative correction of chest wall deformity, which can ensure wound healing while retaining the orthopedic plate to the maximum extent to ensure the effect of the correction.

8.
Int Wound J ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34636163

RESUMO

We aimed to explore the clinical significance of the secondary pedicle amputation of the repair of distal defects with pedicled axial flap. Five patients who underwent pedicled axial flap transfer to repair a large area of skin and soft tissue defects in our hospital were included in this retrospective study. Detailed information including general data and clinical data, such as preoperative complication, type of primary wound, the distance between the primary wound and the donor site (cm), postoperative complications, and types of axial flap were collected. The patients had good joint movement at 6 months after pedicle amputation. At 48 hours after transplantation, except for the last patient (NO.5), there were no obvious complications such as blood supply disorder, infection, and incision dehiscence of the patients, and the flaps survived well. Just after pedicle amputation, 3 and 6 months after pedicle amputation, the flaps survived well with good local morphology. Forty-eight hours after operation, part of the distal flap in the last patient (NO.5) was necrotic. After 6 months of pedicle amputation, part of the flap was transferred to the distal wound again. At 6 months after pedicle amputation, these patients could accept local scars even though the scar of the last patient was obvious. The secondary pedicle amputation of the repair of distal defects with axial flap could avoid the compression of the vascular pedicle in the subcutaneous tunnel between the donor site and the primary wound, which may ensure the bold supply and increase the survival rate of the flap.

9.
Opt Express ; 29(18): 29557-29566, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34615064

RESUMO

We report very low-loss deuterated silicon nitride (SiNx:D) micro-ring resonators fabricated by back-end CMOS compatible low-temperature plasma-enhanced chemical vapor deposition (PECVD) without annealing. Strong confinement micro-ring resonators with a quality factor of > 2 million are achieved, corresponding to a propagation loss in the 1460-1610 nm wavelength range of ∼ 0.17 dB/cm. We further report the generation of low-noise coherent Kerr microcomb states including different perfect soliton crystals (PSC) in PECVD SiNx:D micro-ring resonators. These results manifest the promising potential of the back-end CMOS compatible SiNx:D platform for linear and nonlinear photonic circuits that can be co-integrated with electronics.

10.
J Phys Condens Matter ; 34(5)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34695817

RESUMO

In this article, we propose a quantitative, non-destructive and noninvasive approach to obtain electromagnetic properties of liquid specimens utilizing a home-designed near-field microwave microscopy. The responses of aqueous solutions can be acquired with varying concentrations, types (CaCl2, MgCl2, KCl and NaCl) and tip-sample distances. An electromagnetic simulation model also successfully predicts the behaviors of saline samples. For a certain type of solutions with varying concentrations, the results are concaves with different bottoms, and the symmetric graphs of concave extractions can clearly identify different specimens. Moreover, we obtain electromagnetic images of capillaries with various saline solutions, as well as a Photinia × fraseri Dress leaf.

11.
Macromol Biosci ; : e2100342, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34706143

RESUMO

Recently, various tissue engineering based strategies have been pursued for the regeneration of tracheal tissues. However, previously developed tracheal scaffolds do not accurately mimic the microstructure and mechanical behavior of the native trachea, which restrict their clinical translation. Here, tracheal scaffolds are fabricated by using 3D printing and short nanofibers (SF) dispersion of poly(l-lactide)/gelatin (0.5-1.5 wt%) to afford tracheal constructs. The results display that the scaffolds containing 1.0 wt % of SF exhibit low density, good water absorption capacity, reasonable degradation rate, and stable mechanical properties, which were comparable to the native trachea. Moreover, the designed scaffolds possess good biocompatibility and promote the growth and infiltration of chondrocytes in vitro. The biocompatibility of tracheal scaffolds is further assessed after subcutaneous implantation in mice for up to 4 and 8 weeks. Histological assessment of tracheal constructs explanted at week 4 shows that scaffolds can maintain their structural integrity and support the formation of neo-vessels. Furthermore, cell-scaffold constructs gradually form cartilage-like tissues, which mature with time. Collectively, these engineered tracheal scaffolds not only possess appropriate mechanical properties to afford a stabilized structure but also a biomimetic extracellular matrix-like structure to accomplish tissue regeneration, which may have broad implications for tracheal regeneration.

12.
Nat Commun ; 12(1): 5991, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645803

RESUMO

The reticulon-3 (RTN3)-driven targeting complex promotes clearance of misfolded prohormones from the endoplasmic reticulum (ER) for lysosomal destruction by ER-phagy. Because RTN3 resides in the cytosolic leaflet of the ER bilayer, the mechanism of selecting misfolded prohormones as ER-phagy cargo on the luminal side of the ER membrane remains unknown. Here we identify the ER transmembrane protein PGRMC1 as an RTN3-binding partner. Via its luminal domain, PGRMC1 captures misfolded prohormones, targeting them for RTN3-dependent ER-phagy. PGRMC1 selects cargos that are smaller than the large size of other reported ER-phagy substrates. Cargos for PGRMC1 include mutant proinsulins that block secretion of wildtype proinsulin through dominant-negative interactions within the ER, causing insulin-deficiency. Chemical perturbation of PGRMC1 partially restores WT insulin storage by preventing ER-phagic degradation of WT and mutant proinsulin. Thus, PGRMC1 acts as a size-selective cargo receptor during RTN3-dependent ER-phagy, and is a potential therapeutic target for diabetes.


Assuntos
Proteínas de Transporte/genética , Retículo Endoplasmático/metabolismo , Células Secretoras de Insulina/metabolismo , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Proinsulina/genética , Receptores de Progesterona/genética , Animais , Autofagia/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/genética , Expressão Gênica , Células HEK293 , Humanos , Células Secretoras de Insulina/citologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Mutação , Proteínas do Tecido Nervoso/metabolismo , Cultura Primária de Células , Proinsulina/metabolismo , Ligação Proteica , Domínios Proteicos , Dobramento de Proteína , Proteólise , Ratos , Receptores de Progesterona/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-34653302

RESUMO

Switching materials in channels of nonlinear optics (NLOs) are of particular interest in NLO material science. Numerous crystalline NLO switches based on structural phase transition have emerged, but most of them reveal a single-step switch between two different second-harmonic-generation (SHG) states, and only very rare cases involve three or more SHG states. Herein, we report a new organic-inorganic hybrid salt, (Me3 NNH2 )2 [CdI4 ], which is an unprecedented case of a reversible three-step NLO switch between SHG-silent, -medium, -low, and -high states, with high contrasts of 25.5/4.3/9.2 in a temperature range of 213-303 K. By using the combined techniques of variable-temperature X-ray single-crystal structural analyses, dielectric constants, solid-state 13 C nuclear magnetic resonance spectroscopy, and Hirshfeld surface analyses, we disclose that this four-state switchable SHG behavior is highly associated with the stepwise-changed molecular dynamics of the polar organic cations. This finding demonstrates well the complexity of molecular dynamics in simple hybrid salts and their potential in designing new advanced multistep switching materials.

14.
J Gastrointest Oncol ; 12(4): 1223-1227, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532082

RESUMO

Background: Surgery remains the mainstay of treatment for esophageal squamous cell carcinoma (ESCC), during which lymph node (LN) dissection, especially recurrent laryngeal nerve (RLN) LN dissection, is particularly important and challenging. This study aimed to investigate the LN metastasis of stage T1b mid-thoracic ESCC and explore the clinical value of RLN LN dissection. Methods: The clinicopathological data of 254 patients with stage T1b mid-thoracic ESCC who underwent the McKeown procedure ("tri-incisional esophagectomy") and three-field LN dissection (3FD) at Fujian Cancer Hospital from January 2010 to December 2015 were retrospectively analyzed. The value of LN dissection (especially RLN LNs) was evaluated by calculating the metastasis rate of each LN station. The efficacy index (EI) of the dissection was calculated by multiplying the frequency (%) of metastases to a station and the 5-year survival rate (%) of patients with metastases to that station, and then dividing by 100. Results: The stage T1b mid-thoracic ESCC had the highest rate of metastasis in the paracardiac LNs (4.3%), followed by RLN LNs (2.8%) and the left gastric artery LNs (2.8%). The 5-year survival rate was highest in patients who received lesser gastric curvature LN dissection (100%), followed by patients who underwent right RLN LN dissection (80%), and was 50% in patients who had undergone dissection of the left RLN LNs, upper paraesophageal LNs, subcarinal LNs, and left gastric artery LNs, respectively. In addition, dissection of the right RLN LNs had the highest EI value (2.2), followed by the dissection of LNs along the lesser curvature of the stomach (1.6) and left gastric artery LNs (1.4). Conclusions: Right RLN LNs have a metastasis rate only lower than that of the paracardiac LNs, but could be the most valuable location for performing dissection.

15.
Ann Transl Med ; 9(16): 1330, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532467

RESUMO

Background: Lung squamous cell carcinoma (LUSC) is characterized by frequent mutations of tumor protein p53 (TP53) and cyclin dependent kinase inhibitor 2A (CDKN2A). However, to date, the impact of TP53/CDKN2A status on the clinical outcome of patients with early-stage LUSC is unclear. Methods: Tissue samples from 16 early-stage, surgically resected LUSCs were analyzed by next-generation sequencing (NGS). Information regarding TP53 and CDKN2A alterations and patient survival time was downloaded from The Cancer Genome Atlas (TCGA) database. The associations between TP53 and CDKN2A status and tumor characteristics, outcomes including overall survival (OS) and disease-free survival (DFS), and mutation counts were investigated. Results: TP53 and CDKN2A exhibited a high frequency of somatic mutations in early-stage LUSC in our center. Data for 1,176 samples were collected from TCGA. CDKN2A mutation status was associated with TP53 mutation status (P=0.040). TP53 mutation was a favorable prognostic factor for early-stage LUSC. The OS times of patients with wild-type and mutated TP53 were 28.94 and 60.48 months, respectively (P=0.002). In contrast, CDKN2A mutations were significantly associated with a shorter survival time in early-stage LUSC. The OS times for wild-type and mutated CDKN2A patients were 62.81 and 37.55 months, respectively (P=0.026). Patients with TP53 mutations had higher total mutation counts compared to patients with wild-type TP53. Furthermore, OS was significantly shorter in patients with a low mutation count compared to patients with a median or high mutation count. Conclusions: Early-stage LUSC patients with TP53 mutations had a longer OS, while those with CDKN2A mutations had a shorter OS. Furthermore, patients with TP53 mutation/CDKN2A wild-type status had a longer OS. CDKN2A mutation is a vital indicator for prognostic assessment according to TP53 status. The prolonged survival of patients with TP53 mutations may be due to their high mutation counts. Larger datasets are required to validate these observations.

16.
Ann Transl Med ; 9(16): 1349, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532486

RESUMO

Background: To investigate the expression of long non-coding RNA (lncRNA) Snorna hostgene16 (SNHG16) in sciatic nerve injury tissues and cells. The molecular mechanism of SNHG16 regulating signal activator of transcription 3 (STAT3) expression through "sponge" adsorption of miR-93-5p was also studied. Methods: A rat model of sciatic nerve injury was established, and primary Schwann cells (SCs) were extracted. The expression of SNHG16 in animal tissues with sciatic nerve injury and SCs treated with ischemia and hypoxia was detected by qPCR, and CCK-8 assay, cell scratch assay, and Transwell chamber assay were used to detect cell proliferation, migration, and invasion. The targeted binding of SNHG16 to miR-93-5p was verified by double luciferase reporter gene assay and miRNA immunoprecipitation assay. MiR-93-5p mimic, SNHG16 overexpression vector, and sh-STAT3 plasmid were transfected into cells, respectively, and the mRNA expressions of SNHG16, miR-93-5p, and STAT3 in the cells were detected by qPCR. Results: The expression of lncRNA SNHG16 was decreased after sciatic nerve injury, while overexpression of SNHG16 promoted the proliferation, migration, and invasion of SCs. The results of dual luciferase reporter gene assay and miRNA immunoprecipitation reaction showed miR-93-5p interacted with SNHG16, and the overexpression of miR-93-5p reversed the promoting effects of SNHG16 on the proliferation and invasion of SCs. At the same time, the knockdown of STAT3, which is the target gene of miR-93-5p, reversed the proliferation and invasion promotion effect of SNHG16 on SCs. SNHG16 affected the expression of its downstream target gene STAT3 by adsorbing miR-93-5p via endogenous competitive sponge. Conclusions: SNHG16 can regulate STAT3 expression by sponge adsorption of miR-93-5p in SCs, and SNHG16 and miR-93-5p can be used as potential targets for the diagnosis and treatment of sciatic nerve injury.

17.
Nanoscale ; 13(35): 15074-15084, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533548

RESUMO

A novel medium-entropy nitride (MEN) - CrCoNiN doped with Al and Ti was prepared using magnetron sputtering. The new MEN possesses a single-phase face-centered cubic (FCC) structure, offering a superior combination of hardness (∼21.2 GPa) and fracture toughness (∼4.53 MPa m1/2) that surpasses those of most of the conventional and high-entropy ceramics. The ultrahigh hardness value is attributed to a combined effect of lattice friction, solid solution, nanograin structure and compressive residual stress. The exceptional damage tolerance of the new nitride is underlain by the formation and operation of multiple steady shear bands and amorphization mediated by dislocation accumulations. The discovery of the deformation-induced amorphization and extensive shear banding in the MEN, in conjunction with the mechanistic understanding of the critical roles of high dislocation density and large lattice resistance in dislocation-mediated solid-state amorphization, opens up a new frontier for the development of damage-tolerant MPENs for application under extreme loading conditions.

18.
J Genet Genomics ; 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34538772

RESUMO

The origination of new genes contributes to the biological diversity of life. New genes may quickly build their network, exert important functions, and generate novel phenotypes. Dating gene age and inferring the origination mechanisms of new genes, like primate-specific genes, is the basis for the functional study of the genes. However, no comprehensive resource of gene age estimates across species is available. Here, we systematically date the age of 9,102,113 protein-coding genes from 565 species in the Ensembl and Ensembl Genomes databases, including 82 bacteria, 57 protists, 134 fungi, 58 plants, 56 metazoa, and 178 vertebrates, using a protein-family-based pipeline with Wagner parsimony algorithm. We also collect gene age estimate data from other studies and uniformly distribute the gene age estimates to time ranges in a million years for comparison across studies. All the data are cataloged into GenOrigin (http://genorigin.chenzxlab.cn/), a user-friendly new database of gene age estimates, where users can browse gene age estimates by species, age, and gene ontology. In GenOrigin, the information such as gene age estimates, annotation, gene ontology, ortholog, and paralog, as well as detailed gene presence/absence views for gene age inference based on the species tree with evolutionary timescale, is provided to researchers for exploring gene functions.

19.
Nat Commun ; 12(1): 5349, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504081

RESUMO

There is great interest in the development of micromotors which can convert energy to motion in sub-millimeter dimensions. Micromachines take the micromotor concept a step further, comprising complex systems in which multiple components work in concert to effectively realize complex mechanical tasks. Here we introduce light-driven micromotors and micromachines that rely on optoelectronic tweezers (OET). Using a circular micro-gear as a unit component, we demonstrate a range of new functionalities, including a touchless micro-feed-roller that allows the programming of precise three-dimensional particle trajectories, multi-component micro-gear trains that serve as torque- or velocity-amplifiers, and micro-rack-and-pinion systems that serve as microfluidic valves. These sophisticated systems suggest great potential for complex micromachines in the future, for application in microrobotics, micromanipulation, microfluidics, and beyond.

20.
J Healthc Eng ; 2021: 6923823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567486

RESUMO

Recurrent respiratory tract infections in children are common. It means that children are repeatedly exposed to external pathogens within a certain time, and the clinical symptoms are reciprocating. This article carries out nursing intervention on children's respiratory tract infection through comprehensive nursing methods and analyzes the intervention effect. Moreover, this paper uses a controlled trial to study the nursing methods of recurrent respiratory tract infections in children. In addition, this paper determines and screens test samples according to relevant standards, conducts different nursing methods on samples of different groups, and compares them with the same indicators. Finally, this paper combines mathematical statistics to make statistics of experimental results and draws tables and statistical graphs. By comparing multiple parameters, it can be seen that the comprehensive nursing intervention has a good effect on the nursing of children with respiratory tract infection compared with the traditional nursing intervention, so this nursing method can be expanded in the future.

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