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Microalgae are increasingly playing a significant role in many areas of research and development. Recent studies have demonstrated their ability to aid wound healing by their ability to generate oxygen, aiding the healing process. Bearing this in mind, the capability to spray/spin deposit microalgae in suspension (solution) or compartmentalize living microalgae within architectures such as fibers/scaffolds and beads, would have significance as healing mechanisms for addressing a wide range of wounds. Reconstructing microalgae-bearing architectures as either scaffolds or beads could be generated via electric field (bio-electrospraying and cell electrospinning) and non-electric field (aerodynamically assisted bio-jetting/threading) driven technologies. However, before studying the biomechanical properties of the generated living architectures, the microalgae exposed to these techniques must be interrogated from a molecular level upward first, to establish these techniques, have no negative effects brought on the processed microalgae. Therefore these studies, demonstrate the ability of both these jetting and threading technologies to directly handle living microalgae, in suspension or within a polymeric suspension, safely, and form algae-bearing architectures such as beads and fibers/scaffolds.
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The majority of dislocations in nitride epilayers are edge threading dislocations (TDs), which diminish the performance of nitride devices. However, it is extremely difficult to reduce the edge TDs due to the lack of available slip systems. Here, we systematically investigate the formation mechanism of edge TDs and find that besides originating at the coalescence boundaries, these dislocations are also closely related to geometrical misfit dislocations at the interface. Based on this understanding, we propose a novel strategy to reduce the edge TD density of the GaN epilayer by nearly 1 order of magnitude via graphene-assisted remote heteroepitaxy. The first-principles calculations confirm that the insertion of graphene dramatically reduces the energy barrier required for interfacial sliding, which promotes a new strain release channel. This work provides a unique approach to directly suppress the formation of edge TDs at the source, thereby facilitating the enhanced performance of photoelectronic and electronic devices.
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X-ray diffraction from dislocation half-loops consisting of a misfit segment with two threading arms extending from it to the surface is calculated by the Monte Carlo method. The diffraction profiles and reciprocal space maps are controlled by the ratio of the total lengths of the misfit and the threading segments of the half-loops. A continuous transformation from the diffraction characteristic of misfit dislocations to that of threading dislocations with increasing thickness of epitaxial film is studied. Diffraction from dislocations with edge- and screw-type threading arms is considered and the contributions of the two types of dislocations are compared.
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The rapid development of information technology has made the amount of information in massive texts far exceed human intuitive cognition, and dependency parsing can effectively deal with information overload. In the background of domain specialization, the migration and application of syntactic treebanks and the speed improvement in syntactic analysis models become the key to the efficiency of syntactic analysis. To realize domain migration of syntactic tree library and improve the speed of text parsing, this paper proposes a novel approach-the Double-Array Trie and Multi-threading (DAT-MT) accelerated graph fusion dependency parsing model. It effectively combines the specialized syntactic features from small-scale professional field corpus with the generalized syntactic features from large-scale news corpus, which improves the accuracy of syntactic relation recognition. Aiming at the problem of high space and time complexity brought by the graph fusion model, the DAT-MT method is proposed. It realizes the rapid mapping of massive Chinese character features to the model's prior parameters and the parallel processing of calculation, thereby improving the parsing speed. The experimental results show that the unlabeled attachment score (UAS) and the labeled attachment score (LAS) of the model are improved by 13.34% and 14.82% compared with the model with only the professional field corpus and improved by 3.14% and 3.40% compared with the model only with news corpus; both indicators are better than DDParser and LTP 4 methods based on deep learning. Additionally, the method in this paper achieves a speedup of about 3.7 times compared to the method with a red-black tree index and a single thread. Efficient and accurate syntactic analysis methods will benefit the real-time processing of massive texts in professional fields, such as multi-dimensional semantic correlation, professional feature extraction, and domain knowledge graph construction.
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In this work, we report on the efficiency of single InGaN/GaN quantum wells (QWs) grown on thin (<1 µm) GaN buffer layers on silicon (111) substrates exhibiting very high threading dislocation (TD) densities. Despite this high defect density, we show that QW emission efficiency significantly increases upon the insertion of an In-containing underlayer, whose role is to prevent the introduction of point defects during the growth of InGaN QWs. Hence, we demonstrate that point defects play a key role in limiting InGaN QW efficiency, even in samples where their density (2-3 × 109 cm-2) is much lower than that of TD (2-3 × 1010 cm-2). Time-resolved photoluminescence and cathodoluminescence studies confirm the prevalence of point defects over TDs in QW efficiency. Interestingly, TD terminations lead to the formation of independent domains for carriers, thanks to V-pits and step bunching phenomena.
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We use molecular dynamics simulations to explore concentrated solutions of semiflexible polyelectrolyte ring polymers, akin to the DNA mini-circles, with counterions of different valences. We find that the assembly of rings into nanoscopic cylindrical stacks is a generic feature of the systems, but the morphology and dynamics of such a cluster can be steered by the counterion conditions. In general, a small addition of trivalent ions can stabilize the emergence of clusters due to the counterion condensation, which mitigates the repulsion between the like-charged rings. Stoichiometric addition of trivalent ions can even lead to phase separation of the polyelectrolyte ring phase due to the ion-bridging effects promoting otherwise entropically driven clustering. On the other hand, monovalent counterions cause the formation of stacks to be re-entrant with density. The clusters are stable within a certain window of concentration, while above the window the polyelectrolytes undergo an osmotic collapse, disfavoring ordering. The cluster phase exhibits characteristic cluster glass dynamics with arrest of collective degrees of freedom but not the self-ones. On the other hand, the collapsed phase shows arrest on both the collective and single level, suggesting an incipient glass-to-glass transition, from a cluster glass of ring clusters to a simple glass of rings.
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To restore severely damaged teeth to the greatest state for health, function, and aesthetics continues to be a challenge for all practising dental surgeons. A pin retained restoration is an intricate restoration involving the insertion of one or more pins into the dentin to provide sufficient resistance and retention. These pins help in anchoring dental amalgam or composite to the tooth structure. This auxiliary retentive means help in the restoration of mutilated teeth in young individuals whose pulp chambers are relatively large and the dentinal tubules are comparatively immature. This case study sheds insights on the successful rehabilitation of a severely damaged premolar tooth with pins and composite resin restoration.
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Amálgama Dentário , Restauração Dentária Permanente , Humanos , Restauração Dentária Permanente/métodos , Pinos Dentários , Resinas Compostas , Dente Pré-Molar/cirurgiaRESUMO
The synaptic protein-DNA complexes, formed by specialized proteins that bridge two or more distant sites on DNA, are critically involved in various genetic processes. However, the molecular mechanism by which the protein searches for these sites and how it brings them together is not well understood. Our previous studies directly visualized search pathways used by SfiI, and we identified two pathways, DNA threading and site-bound transfer pathways, specific to the site-search process for synaptic DNA-protein systems. To investigate the molecular mechanism behind these site-search pathways, we assembled complexes of SfiI with various DNA substrates corresponding to different transient states and measured their stability using a single-molecule fluorescence approach. These assemblies corresponded to specific-specific (synaptic), non-specific-non-specific (non-specific), and specific-non-specific (pre-synaptic) SfiI-DNA states. Unexpectedly, an elevated stability in pre-synaptic complexes assembled with specific and non-specific DNA substrates was found. To explain these surprising observations, a theoretical approach that describes the assembly of these complexes and compares the predictions with the experiment was developed. The theory explains this effect by utilizing entropic arguments, according to which, after the partial dissociation, the non-specific DNA template has multiple possibilities of rebinding, effectively increasing the stability. Such difference in the stabilities of SfiI complexes with specific and non-specific DNA explains the utilization of threading and site-bound transfer pathways in the search process of synaptic protein-DNA complexes discovered in the time-lapse AFM experiments.
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DNA , Desoxirribonucleases de Sítio Específico do Tipo II , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , DNA/química , Proteínas/metabolismo , Ligação Proteica , Replicação do DNARESUMO
Heteroepitaxial growth of high Al-content AlGaN often results in a high density of threading dislocations and surface hexagonal hillocks, which degrade the performance and reliability of AlGaN-based UVC light emitting diodes (LEDs). In this study, the degradation mechanism and impurity/defect behavior of UVC LEDs in relation to the hexagonal hillocks have been studied in detail. It was found that the early degradation of UVC LEDs is primarily caused by electron leakage. The prominent contribution of the hillock edges to the electron leakage is unambiguously evidenced by the transmission electron microscopy measurements, time-of-flight secondary ion mass spectrometry, and conductive atomic force microscopy. Dislocations bunching and segregation of impurities, including C, O, and Si, at the hillock edges are clearly observed, which facilitate the trap-assisted carrier tunneling in the multiple quantum wells and subsequent recombination in the p-AlGaN. This work sheds light on one possible degradation mechanism of AlGaN-based UVC LEDs.
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BACKGROUND: Thread lifting is a minimally invasive aesthetic procedure that lifts and realigns sagging tissue. Definisse double-needle threads are the latest fourth generation absorbable, monofilament, suspension barbed threads of synthetic origin with convergent bidirectional barbs. Definisse thread produces dual action; mechanical action gives a lifting effect and over a period, it promotes histological revitalizing action. OBJECTIVES: To evaluate the real-world efficacy and safety of Definisse double-needle threads for lower facial lifting for jaw line reshaping in Indian patients. METHODS: This is an observational, retrospective study involving patients who underwent treatment for lower-face reshaping using Definisse double-needle 12 cm threads. RESULTS: Fifty patients with a mean age of 47.44 years were included in the study with an average follow-up of 5.14 months. All the patients have undergone Jawline Reshaping (JR) procedure, while 70% of patients also underwent Malar Reshaping (MR) technique simultaneously. Mean of Physician and Subject Global Aesthetic Improvement Scale (PGAIS and SGAIS) showed improvement immediately after the procedure (mean scores 2.82 and 2.7, respectively) and showed further improvement at the follow-up (3.72 and 3.58, respectively). Moreover, most of the patients immediately after the procedure rated the improvement in PGAIS and SGAIS as "much improved" compared to pre-procedure appearance (78% and 66%, respectively), while, at follow-up, 76% and 66% of the patients, respectively, rated "improved very much" compared to pre-procedure appearance. CONCLUSION: Current study has demonstrated the effectiveness of the latest Definisse threads in Indian patients in performing tissue repositioning to provide a noticeable lifting effect. Procedure was also well tolerated and none of the patients developed serious complications.
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Ritidoplastia , Humanos , Pessoa de Meia-Idade , Ritidoplastia/métodos , Estudos Retrospectivos , Rejuvenescimento , Suturas , AgulhasRESUMO
In detection-free tracking, after users freely designate the location of the object to be tracked in the first frame of the video sequence, the location of the object is continuously found in the following video frame sequence. Recently, technologies using a Siamese network and transformer based on DNN modules have been evaluated as very excellent in terms of tracking accuracy. The high computational complexity due to the usage of the DNN module is not a preferred feature in terms of execution speed, and when tracking two or more objects, a bottleneck effect occurs in the DNN accelerator such as the GPU, which inevitably results in a larger delay. To address this problem, we propose a tracker scheduling framework. First, the computation structures of representative trackers are analyzed, and the scheduling unit suitable for the execution characteristics of each tracker is derived. Based on this analysis, the decomposed workloads of trackers are multi-threaded under the control of the scheduling framework. CPU-side multi-threading leads the GPU to a work-conserving state while enabling parallel processing as much as possible even within a single GPU depending on the resource availability of the internal hardware. The proposed framework is a general-purpose system-level software solution that can be applied not only to GPUs but also to other hardware accelerators. As a result of confirmation through various experiments, when tracking two objects, the execution speed was improved by up to 55% while maintaining almost the same accuracy as the existing method.
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The analysis of the relationship between sequence and structure similarities during the evolution of a protein family has revealed a limit of sequence divergence for which structural conservation can be confidently assumed and homology modeling is reliable. Below this limit, the twilight zone corresponds to sequence divergence for which homology modeling becomes increasingly difficult and requires specific methods. Either with conventional threading methods or with recent deep learning methods, such as AlphaFold, the challenge relies on the identification of a template that shares not only a common ancestor (homology) but also a conserved structure with the query. As both homology and structural conservation are transitive properties, mining of sequence databases followed by multidimensional scaling (MDS) of the query sequence space can reveal intermediary sequences to infer homology and structural conservation between the query and the template. Here, as a case study, we studied the plethodontid receptivity factor isoform 1 (PRF1) from Plethodon jordani, a member of a pheromone protein family present only in lungless salamanders and weakly related to cytokines of the IL6 family. A variety of conventional threading methods led to the cytokine CNTF as a template. Sequence mining, followed by phylogenetic and MDS analysis, provided missing links between PRF1 and CNTF and allowed reliable homology modeling. In addition, we compared automated models obtained from web servers to a customized model to show how modeling can be improved by expert information.
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Fator Neurotrófico Ciliar , Software , Filogenia , Análise de Sequência de Proteína/métodos , Citocinas , AlgoritmosRESUMO
The ability to successfully predict the three-dimensional structure of a protein from its amino acid sequence has made considerable progress in the recent past. The progress is propelled by the improved accuracy of deep learning-based inter-residue contact map predictors coupled with the rising growth of protein sequence databases. Contact map encodes interatomic interaction information that can be exploited for highly accurate prediction of protein structures via contact map threading even for the query proteins that are not amenable to direct homology modeling. As such, contact-assisted threading has garnered considerable research effort. In this chapter, we provide an overview of existing contact-assisted threading methods while highlighting the recent advances and discussing some of the current limitations and future prospects in the application of contact-assisted threading for improving the accuracy of low-homology protein modeling.
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Algoritmos , Análise de Sequência de Proteína , Análise de Sequência de Proteína/métodos , Proteínas/química , Software , Sequência de Aminoácidos , Bases de Dados de Proteínas , Conformação Proteica , Dobramento de ProteínaRESUMO
The aim of this paper is to model the effects of threading dislocations on both gate and drain currents of AlGaN/GaN high electron mobility transistors (HEMTs). The fraction of filled traps increases with the threading dislocations, while the trapping effects cause a decrease in drain current and an increase in gate leakage current. To model the drain current drop, the two simplified RC subcircuits with diodes are proposed to capture the charge trapping/detrapping characteristics. The trap voltages Vg_trap and Vd_trap generated by RC networks are fed back into the model to capture the effects of traps on drain current. Considering acceptor-decorated dislocations, we present a novel Poole-Frenkel (PF) model to precisely describe the reverse leakage gate current, which plays a dominant role in the gate leakage current. The proposed model, which uses physical parameters only, is implemented in Verilog-A. It is in excellent agreement with the experimental data.
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Human epidermal growth factor receptor (EGFR) has been established as a therapeutic target of lung cancer and other diverse tumors. The antibody drug Cetuximab has been developed to target the third subdomain III (TSDIII) of EGFR extracellular domain (ECD) by competitively inhibiting epidermal growth factor binding. In this study, we performed systematic investigation on the crystal complex structure of EGFR ECD domain with Cetuximab to create a residue importance profile for the TSDIII subdomain, based on which a number of U-shaped, double-stranded linear peptides were derived and cyclized to orthogonally thread through most hotspot residues and many responsible residues within the TSDIII ß-sheet plane; they represent mimotopes of the key antibody-recognition site of TSDIII subdomain. Computational analyses revealed that these linear peptides cannot spontaneously fold to the desired conformation in free state due to their intrinsic flexibility. Cell-free assays confirmed that the stapling can considerably improve the binding affinity of linear peptides to Cetuximab by up to 18-fold. The cOrt1 [3-18] cyclic peptide was measured to have the highest affinity in all designed linear and cyclic peptides.
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Anticorpos Monoclonais , Neoplasias Pulmonares , Humanos , Cetuximab/uso terapêutico , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Conformação Proteica em Folha beta , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Peptídeos/química , Linhagem Celular TumoralRESUMO
BACKGROUND: Traditional middle and lower facelifts are not suitable for patients with mild skin laxity or who wish to avoid incision scars. OBJECTIVE: We present the stab access fascia suspension lift (SAFS-lift) technique, which does not require regular skin incisions, as a reliable surgical facelift strategy for the lower and middle face. METHODS: From September 2020 to September 2021, 38 patients underwent SAFS-lift. SAFS-lift involved (1) incomplete subcutaneous undermining with hydrodissection-assisted tunneling; (2) complete subcutaneous undermining with a dissecting cannula in the zygomatic buccal groove area and hollow below zygomatic arch; and (3) maximal firm superficial musculoaponeurotic system suspension with polydioxanone barbed threads in loops. All patients evaluated the outcome according to the Global Aesthetic Improvement Scale. Four plastic surgeons evaluated postsurgery result with a five-point Likert scale (5 = excellent, 4 = good, 3 = fair, 2 = no change, and 1 = worse). RESULTS: Thirty-six patients were successfully enrolled. The mean follow-up period was 14.72 ± 3.89 months. No patients showed visible scarring 6 months after surgery. The minor complication rate was 19.4%. They all subsided within 1-6 weeks without treatment. No infection, hematoma, seroma, or facial nerve injury was observed. Patients' outcome ratings were 4.22 ± 0.58 (3 months), 4.69 ± 0.46 (6 months), and 4.69 ± 0.54 (1 year). Surgeons' outcome scoring was 3.98 ± 0.95. CONCLUSIONS: Stab access fascia suspension-lift is a predictable, effective, and safe facelift technique that can be performed without making noticeable incisions and resecting the skin.
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Ritidoplastia , Sistema Musculoaponeurótico Superficial , Humanos , Ritidoplastia/métodos , Cicatriz/cirurgia , Sistema Musculoaponeurótico Superficial/cirurgia , Zigoma , FásciaRESUMO
In fake news detection, intelligent optimization seems to be a more effective and explainable solution methodology than the black-box methods that have been extensively used in the literature. This study takes the optimization-based method one step further and proposes a novel, multi-thread hybrid metaheuristic approach for fake news detection in social media. The most innovative feature of the proposed method is that it uses a supervisor thread mechanism, which simultaneously monitors and improves the performance and search patterns of metaheuristic algorithms running parallel. With the supervisor thread mechanism, it is possible to analyse different key attribute combinations in the search space. In addition, this study develops a software framework that allows this model to be implemented easily. It tests the performance of the proposed model on three different data sets, respectively containing news about Covid-19, the Syrian War, and daily politics. The proposed method is evaluated in comparison to the results of fifteen different well-known deep models and classification algorithms. Experimental results prove the success of the proposed model and that it can produce competitive results.
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Unprecedented threading kinetics were revealed between viologen-based guests and conformationally adaptive oxatub[4]arene. Three representative conformations of oxatub[4]arene are involved in the kinetic and thermodynamic products which follow the opposite orders in their rankings. Consequently, error correction was involved and a complex kinetic process was observed in a simple two-component system. Moreover, it was found that some viologen-based guests have much faster threading kinetics than those of DABCO-based with the same stoppers. This was enabled by an unprecedented threading mechanism in which a tilted conformation of the guests is adopted by involving one linear alkyl group on the 3,5-dialkoxybenzyl stoppers, the viologen core, and the methylene spacers in the transition states. This new mechanism even allows the viologen-based guests with the 3,5-dicetyloxybenzyl stoppers to form a pseudorotaxane with oxatub[4]arene.
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Glioma is one of the most threatening tumors and the survival rate of the infected patient is low. The automatic segmentation of the tumors by reliable algorithms can reduce diagnosis time. In this paper, a novel 3D multi-threading dilated convolutional network (MTDC-Net) is proposed for the automatic brain tumor segmentation. First of all, a multi-threading dilated convolution (MTDC) strategy is introduced in the encoder part, so that the low dimensional structural features can be extracted and integrated better. At the same time, the pyramid matrix fusion (PMF) algorithm is used to integrate the characteristic structural information better. Secondly, in order to make the better use of context semantical information, this paper proposed a spatial pyramid convolution (SPC) operation. By using convolution with different kernel sizes, the model can aggregate more semantic information. Finally, the multi-threading adaptive pooling up-sampling (MTAU) strategy is used to increase the weight of semantic information, and improve the recognition ability of the model. And a pixel-based post-processing method is used to prevent the effects of error prediction. On the brain tumors segmentation challenge 2018 (BraTS2018) public validation dataset, the dice scores of MTDC-Net are 0.832, 0.892 and 0.809 for core, whole and enhanced of the tumor, respectively. On the BraTS2020 public validation dataset, the dice scores of MTDC-Net are 0.833, 0.896 and 0.797 for the core tumor, whole tumor and enhancing tumor, respectively. Mass numerical experiments show that MTDC-Net is a state-of-the-art network for automatic brain tumor segmentation.
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Neoplasias Encefálicas , Processamento de Imagem Assistida por Computador , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , SoftwareRESUMO
BACKGROUND: The eyes are one of the most prominent features of the face. To date, a vast majority of procedures have been described for periorbital rejuvenation. Among them, non-surgical threading is an alternative and minimally invasive technique. OBJECTIVE: We developed a new non-surgical threading technique to achieve long-lasting almond-shaped upturned eyes with brow lifting that we call "brow gliding". We developed a new non-surgical threading technique to achieve long-lasting almond-shaped upturned eyes with brow lifting that we call "brow gliding". Here, we present details of our procedure and the clinical experience of our patients who have at least a 6-month follow-up period. METHODS AND MATERIALS: We used polydioxanone cog threads in combination with knots to lift the lateral sides of the brows and eyes. By burying these knots in the subcutaneous tissue and extending the threads to the scalp fascia, we were able to spread the load of the threads over multiple stable structures in order to achieve an effective lifting impact. RESULTS: According to the subjective assessment scale, all patients described the improvements as very good or beyond expectations after the procedure. During the follow-up period, 4 of 34 (11.8%) patients stated it was very good and 19 of 34 (55.9%) patients stated that it was still beyond expectations. CONCLUSION: The Brow Gliding technique is a promising office-based cosmetic procedure for periorbital aesthetics with a prominent outcome and minimally invasive fashion.