338 research outputs found
Influences of Random Surface Waves on the Estimates of Wind Energy Input to the Ekman Layer in the Antarctic Circumpolar Current Region
Sea surface waves significantly affect the wind energy input to the Ekman layer in the upper ocean. In the study, we first incorporated the wave-induced Coriolis-Stokes forcing, the reduction of wind stress caused by wave generation, and wave dissipation into the classical Ekman model to investigate the kinetic energy balance in the wave-affected Ekman layer. Then, both the theoretical steady state solution for the idealized condition and the nonsteady state solution for the realistic ocean were derived. Total energy input to the wave-affected Ekman layer includes the wind stress energy input and the wave-induced energy input. Based on the WAVEWATCH III model, the wave spectrum was simulated to represent realistic random directional wave conditions. The wind stress energy input and the wave-induced energy input to the wave-affected Ekman layer in the Antarctic Circumpolar Current in the period from 1988 to 2010 were then calculated. The annual mean total energy input in the Antarctic Circumpolar Current region was 402.5 GW and the proportions of the wind stress energy input and the wave-induced energy input were, respectively, 85% and 15%. Particularly, total energy input in the Antarctic Circumpolar Current in the wave-affected Ekman layer model was 59.8% lower than that in the classical Ekman model. We conclude that surface waves play a significant role in the wind energy input to the Ekman layer
NegVSR: Augmenting Negatives for Generalized Noise Modeling in Real-World Video Super-Resolution
The capability of video super-resolution (VSR) to synthesize high-resolution
(HR) video from ideal datasets has been demonstrated in many works. However,
applying the VSR model to real-world video with unknown and complex degradation
remains a challenging task. First, existing degradation metrics in most VSR
methods are not able to effectively simulate real-world noise and blur. On the
contrary, simple combinations of classical degradation are used for real-world
noise modeling, which led to the VSR model often being violated by
out-of-distribution noise. Second, many SR models focus on noise simulation and
transfer. Nevertheless, the sampled noise is monotonous and limited. To address
the aforementioned problems, we propose a Negatives augmentation strategy for
generalized noise modeling in Video Super-Resolution (NegVSR) task.
Specifically, we first propose sequential noise generation toward real-world
data to extract practical noise sequences. Then, the degeneration domain is
widely expanded by negative augmentation to build up various yet challenging
real-world noise sets. We further propose the augmented negative guidance loss
to learn robust features among augmented negatives effectively. Extensive
experiments on real-world datasets (e.g., VideoLQ and FLIR) show that our
method outperforms state-of-the-art methods with clear margins, especially in
visual quality
Exploring Shape Embedding for Cloth-Changing Person Re-Identification via 2D-3D Correspondences
Cloth-Changing Person Re-Identification (CC-ReID) is a common and realistic
problem since fashion constantly changes over time and people's aesthetic
preferences are not set in stone. While most existing cloth-changing ReID
methods focus on learning cloth-agnostic identity representations from coarse
semantic cues (e.g. silhouettes and part segmentation maps), they neglect the
continuous shape distributions at the pixel level. In this paper, we propose
Continuous Surface Correspondence Learning (CSCL), a new shape embedding
paradigm for cloth-changing ReID. CSCL establishes continuous correspondences
between a 2D image plane and a canonical 3D body surface via pixel-to-vertex
classification, which naturally aligns a person image to the surface of a 3D
human model and simultaneously obtains pixel-wise surface embeddings. We
further extract fine-grained shape features from the learned surface embeddings
and then integrate them with global RGB features via a carefully designed
cross-modality fusion module. The shape embedding paradigm based on 2D-3D
correspondences remarkably enhances the model's global understanding of human
body shape. To promote the study of ReID under clothing change, we construct 3D
Dense Persons (DP3D), which is the first large-scale cloth-changing ReID
dataset that provides densely annotated 2D-3D correspondences and a precise 3D
mesh for each person image, while containing diverse cloth-changing cases over
all four seasons. Experiments on both cloth-changing and cloth-consistent ReID
benchmarks validate the effectiveness of our method.Comment: Accepted by ACM MM 202
Phonon tunnels from a sonic black hole
We investigate the phonon radiation from a spherically symmetrical,
stationary, viscid-free son-ic black hole by using a semi-classical method. The
backreaction of the radiated phonon is taken into account. We obtain the phonon
emission temperature, and it is consistent with the Hawking's formula
Imobilizacija tirozinaze na pustu od ugljičnih vlakana s (3-aminopropil)trietoksisilanom za protočnu elektrokemijsku detekciju fenolnih spojeva
Tyrosinase (TYR) was covalently immobilized onto amino-functionalized carbon felt (CF) surface via glutaraldehyde (GA). Prior to the TYR-immobilization, primary amino group was introduced to the CF surface by treatment with 3-aminopropyltriethoxysilane (APTES). The resulting TYR-immobilized CF was used as a working electrode unit of an electrochemical flow-through detector for mono- and di-phenolic compounds (i.e., catechol, p-cresol, phenol and p-chlorophenol). Additionally, flow injection peaks based on electroreduction of the enzymatically produced o-quinone species were detected at −0.05 V vs. Ag/AgCl. The resulting TYR/GA/APTES/CF biosensor responded well to all compounds tested with limits of detection range from 7.5 to 35 nmol l–1 (based on three times S/N ratio). Moreover, such modified electrode exhibits good stability and reproducibility for catechol. No serious degradation of the peak current was found over 30 consecutive injections.
This work is licensed under a Creative Commons Attribution 4.0 International License.Tirozinaza (TYR) je kovalentno vezana na aminiranu površinu pusta izrađenog od ugljičnih vlakana (CF) s pomoću glutaraldehida (GA). Prije imobilizacije tirozinaze primarna amino-skupina uvedena je na ugljična vlakna (3-aminopropil)trietoksisilanom (APTES). CF s imobiliziranom tirozinazom upotrijebljen je kao elektroda u protočnom elektrokemijskom detektoru jednostruko i dvostruko hidroksiliranih fenola (katehol, p-krezol, fenol, p-klorfenol).
Pri − 0,05 V (u odnosu na Ag/AgCl) uočeni su protočni injekcijski signali elektroredukcije o-kinona nastalog enzimskom reakcijom. Biosenzor TYR/GA/APTES/CF dobro se odaziva za sve ispitane spojeve uz detekcijski limit od 7,5 do 35 nmol l–1 (tri puta veći signal od šuma). Modificirana elektroda stabilna je i pokazuje dobru reproducibilnost za katehol. Jakost struje signala nije se značajno smanjila ni nakon 30 uzastopnih injektiranja.
Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna
Case report: A rare DLST mutation in patient with metastatic pheochromocytoma: clinical implications and management challenges
BackgroundPheochromocytoma is one of the most hereditary human tumors with at least 20 susceptible genes undergoing germline and somatic mutations, and other mutations less than 1% -2%. In recent years, other rare mutations have gradually been discovered to be possibly related to the pathogenesis and metastasis of pheochromocytoma. Most patients with pheochromocytoma experience common symptoms like headaches, palpitations, and sweating, while some may have less common symptoms. The diversity of symptoms, genetic mutations, and limited treatment options make management challenging.Case presentationA 53-year-old woman was hospitalized after experiencing episodic epigastric pain for one month. A mass was found in her right adrenal gland and she underwent robot-assisted laparoscopic surgery, revealing a pheochromocytoma. At the 16-month follow-up, multiple metastatic lesions consistent with metastatic pheochromocytoma were found. A germline mutation in the dihydrolipoamide succinyltransferase (DLST) gene (c.330 + 14A>G) was detected, and despite trying chemotherapy and adjuvant therapy, the patient had a limited response with an overall survival of 27 months.ConclusionsDLST mutation is one of the rare pheochromocytoma-related mutated genes, and genetic sequencing is crucial for effective clinical management
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