1,180 research outputs found
The Insect Fascicle Morphology Research and Bionic Needle Pierced Mechanical Mechanism Analysis
In this paper, mosquito and cicadas two kinds of insects fascicle were studied, and observed the fascicle surface morphology and distribution through scanning electron microscopy, discussed the height of the six parameters of sawtooth and analyzed quantitatively, compared the two types of fascicle in micro-structure size, and shape, the experiment results show that there are obviously different among the two mouth fascicle morphological structure. Triangular sawtooth are all clearly visible in the two kinds of insect fascicle, in which the mosquito has the small microstructure, and the cicada has the larger one; microstructure of mosquitoes tilt to the rear part of the fascicle, while the microstructure of cicada is symmetric on bottom corner. Based on non-smooth surface structure of fascicle obvious principles of drag reduction effect, the model of drag reduction bionic syringe is proposed, Designed a bionic drag painless needles, and simulated needle piercing power is also measured. Bionic needle surface microstructure can help reduce the needle to decrease the contact area, form rolling, friction, and thus reduce the resistance to needle piercing. Bionic needle has been proved that its puncture resistance is less than smooth one consequently has significant drag reduction effects. Keywords: Insects fascicle; surface morphology; bionic needles; drag reductio
Normalized Solutions to Nonautonomous Kirchhoff Equation
In this paper, we study the existence of normalized solutions to the
following Kirchhoff equation with a perturbation: where , . We treat three cases.
(i)When , we obtain the existence of global
constraint minimizers.
(ii)When , we prove the existence of mountain
pass solution.
(iii)When , we establish the existence of
bound state solutions.Comment: arXiv admin note: text overlap with arXiv:2301.07926 by other author
Normalized bound state solutions of fractional Schr\"{o}dinger equations with general potential
In this paper, we study a class of fractional Schr\"{o}dinger equation
\begin{equation} \label{eq0} \left\{ \begin{aligned} &(-\Delta)^{s}u=\lambda
u+a(x)|u|^{p-2}u,\\ &\int_{\mathbb{R}^{N}}|u|^{2}dx=c^{2},\ u\in
H^{s}(\mathbb{R}^{N}), \end{aligned} \right. \end{equation} where ,
and .
is a positive potential function. By using Fixed Point Theorem of Brouwer,
barycenter function and variational method, we obtain the existence of
normalized bound solutions for the problem
A STUDY OF THE LEG JOINTS MUSCLE STRENGTHS RATIOS FOR DIVING ATHLETES
In diving, excellent power is needed for the athletes to complete the complex diving movements. This research focused on studying the relationships between the power and absolute strength as well as the ratios among the strengths of muscle groups of hip, knee and ankle. Further in-depth analysis of these relationships was also conducted
BIOMECHANICAL ANALYSIS OF BACK HANDSPRING TO BACKWARD SALTO WITH TRIPLE TWIST IN GYMNASTIC FLOOR EXERCISE
INTRODUCTION: The degree of difficulty in gymnastic movements has increased dramatically during the last 30 years, a fact is which is unimaginable to those not skilled in the art. For the gymnast, practice of a new movement is one of the most important ways to learn a new skill. The discipline of Sports Biomechanics can provide the knowledge to increase the efficiency of learning. The purpose of this study was to provide biomechanical analysis of their technique in order to identify specific characteristics and problem areas so that the skill can be mastered in as short a time as possible
Effectiveness and safety of Wuling capsule for post stroke depression: A systematic review
SummaryObjectiveTo review the effectiveness and safety of Wuling capsule for post stroke depression (PSD) systematically.MethodsWe searched electronic databases for randomized controlled trials (RCTs) that compared either Wuling capsule with placebo, no treatment or Wuling capsule plus conventional treatment with conventional treatment alone in adults with post stroke depression. Relevant resources were also retrieved. Two reviewers screened the citations, assessed the risk of bias and extracted data independently.ResultsA total of 16 studies involving 1378 patients were identified for this review. There were 3 trials comparing Wuling capsule with no treatment control and 13 trials comparing Wuling capsule plus conventional treatment (Deanxit, Fluoxetine, Sertraline, Paroxetine or Citalopram) with conventional treatment alone. Meta-analyses indicated Wuling capsule used alone or integrated with conventional treatment was effective for PSD in terms of HAMD (Hamilton depression scale) scores, response rate and with less adverse effects, of which, HAMD scores decreased significantly in favor of Wuling capsule from onset time to 1 week (SMD=1.27, 95%CI: 0.71–1.83, P<0.00001), 2 weeks (SMD=1.45, 95%CI: 0.57–2.33, P=0.001), 4 weeks (SMD=2.84, 95%CI: 2.15–3.52, P<0.00001), 6 weeks (SMD=2.70, 95%CI: 2.15–3.24, P<0.00001), and 8 weeks (SMD=4.53, 95%CI: 3.55–5.50, P<0.00001) and overall effect (SMD=2.40, 95%CI: 1.75–3.05, P<0.00001) (SMD=standardized mean difference).ConclusionWuling capsule appeared to present certain antidepressant effect compared to no treatment control. With a combination of several Western medicines, Wuling capsule could be helpful in strengthening efficacy and reducing the incidence of adverse events as an alternative choice in the treatment of PSD. However, due to the limited number of included trials and relatively moderate methodological quality in the majority of studies, further large scale and rigorously designed trials are warranted to confirm the effectiveness and safety of Wuling capsule for post stroke depression
HyperThumbnail: Real-time 6K Image Rescaling with Rate-distortion Optimization
Contemporary image rescaling aims at embedding a high-resolution (HR) image
into a low-resolution (LR) thumbnail image that contains embedded information
for HR image reconstruction. Unlike traditional image super-resolution, this
enables high-fidelity HR image restoration faithful to the original one, given
the embedded information in the LR thumbnail. However, state-of-the-art image
rescaling methods do not optimize the LR image file size for efficient sharing
and fall short of real-time performance for ultra-high-resolution (e.g., 6K)
image reconstruction. To address these two challenges, we propose a novel
framework (HyperThumbnail) for real-time 6K rate-distortion-aware image
rescaling. Our framework first embeds an HR image into a JPEG LR thumbnail by
an encoder with our proposed quantization prediction module, which minimizes
the file size of the embedding LR JPEG thumbnail while maximizing HR
reconstruction quality. Then, an efficient frequency-aware decoder reconstructs
a high-fidelity HR image from the LR one in real time. Extensive experiments
demonstrate that our framework outperforms previous image rescaling baselines
in rate-distortion performance and can perform 6K image reconstruction in real
time.Comment: Accepted by CVPR 2023; Github Repository:
https://github.com/AbnerVictor/HyperThumbnai
The novel cis-encoded antisense RNA AsrC positively regulates the expression of rpoE-rseABC operon and thus enhances the motility of Salmonella enterica serovar typhi
Bacterial noncoding RNAs are essential in many cellular processes, including response to environmental stress, and virulence. Deep sequencing analysis of the Salmonella enterica serovar Typhi (S. Typhi) transcriptome revealed a novel antisense RNA transcribed in cis on the strand complementary to rseC, an activator gene of sigma factor RpoE. In this study, expression of this antisense RNA was confirmed in S. Typhi by Northern hybridization. Rapid amplification of cDNA ends and sequence analysis identified an 893 bp sequence from the antisense RNA coding region that covered all of the rseC coding region in the reverse direction of transcription. This sequence of RNA was named as AsrC. After overexpression of AsrC with recombinantant plasmid in S. Typhi, the bacterial motility was increased obviously. To explore the mechanism of AsrC function, regulation of rseC and rpoE expression by AsrC was investigated. We found that AsrC increased the levels of rseC mRNA and protein. The expression of rpoE was also increased in S. Typhi after overexpression of AsrC, which was dependent on rseC. Thus, we propose that AsrC increased RseC level and indirectly activating RpoE which can initiate fliA expression and promote the motility of S. Typhi
HumanNorm: Learning Normal Diffusion Model for High-quality and Realistic 3D Human Generation
Recent text-to-3D methods employing diffusion models have made significant
advancements in 3D human generation. However, these approaches face challenges
due to the limitations of text-to-image diffusion models, which lack an
understanding of 3D structures. Consequently, these methods struggle to achieve
high-quality human generation, resulting in smooth geometry and cartoon-like
appearances. In this paper, we propose HumanNorm, a novel approach for
high-quality and realistic 3D human generation. The main idea is to enhance the
model's 2D perception of 3D geometry by learning a normal-adapted diffusion
model and a normal-aligned diffusion model. The normal-adapted diffusion model
can generate high-fidelity normal maps corresponding to user prompts with
view-dependent and body-aware text. The normal-aligned diffusion model learns
to generate color images aligned with the normal maps, thereby transforming
physical geometry details into realistic appearance. Leveraging the proposed
normal diffusion model, we devise a progressive geometry generation strategy
and a multi-step Score Distillation Sampling (SDS) loss to enhance the
performance of 3D human generation. Comprehensive experiments substantiate
HumanNorm's ability to generate 3D humans with intricate geometry and realistic
appearances. HumanNorm outperforms existing text-to-3D methods in both geometry
and texture quality. The project page of HumanNorm is
https://humannorm.github.io/.Comment: The project page of HumanNorm is https://humannorm.github.io
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