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Kaizen: Decomposing cellular images with VQ-VAE
A fundamental problem in cell and tissue biology is finding cells in microscopy images. Traditionally, this detection has been performed by segmenting the pixel intensities. However, these methods struggle to delineate cells in more densely packed micrographs, where local decisions about boundaries are not trivial. Here, we develop a new methodology to decompose microscopy images into individual cells by making object-level decisions. We formulate the segmentation problem as training a flexible factorized representation of the image. To this end, we introduce Kaizen, an approach inspired by predictive coding in the brain that maintains an internal representation of an image while generating object hypotheses over the external image, and keeping the ones that improve the consistency of internal and external representations. We achieve this by training a Vector Quantised-Variational AutoEncoder (VQ-VAE). During inference, the VQ-VAE is iteratively applied on locations where the internal representation differs from the external image, making new guesses, and keeping only the ones that improve the overall image prediction until the internal representation matches the input. We demonstrate Kaizen’s merits on two fluorescence microscopy datasets, improving the separation of nuclei and neuronal cells in cell culture images.
The analysis of motion recognition model for badminton player movements using machine learning
Segmentation-based deep 2D-3D multibranch learning approach for effective hyperspectral image classification
Deep learning has revolutionized the classification of land cover objects in hyperspectral images (HSIs), particularly by managing the complex 3D cube structure inherent in HSI data. Despite these advances, challenges such as data redundancy, computational costs, insufficient sample sizes, and the curse of dimensionality persist. Traditional 2D Convolutional Neural Networks (CNNs) struggle to fully leverage the interconnections between spectral bands in HSIs, while 3D CNNs, which capture both spatial and spectral features, require more sophisticated design. To address these issues, we propose a novel multilayered, multi-branched 2D-3D CNN model in this paper that integrates Segmented Principal Component Analysis (SPCA) and the minimum-Redundancy-Maximum-Relevance (mRMR) technique. This approach explores the local structure of the data and ranks features by significance. Our approach then hierarchically processes these features: the shallow branch handles the least significant features, the deep branch processes the most critical features, and the mid branch deals with the remaining features. Experimental results demonstrate that our proposed method outperforms most of the state-of-the-art techniques on the Salinas Scene, University of Pavia, and Indian Pines hyperspectral image datasets achieving 100%, 99.94%, and 99.12% Overall Accuracy respectively.
Upper limb human-exoskeleton system motion state classification based on semg: application of CNN-BiLSTM-attention model
Boosting classical and quantum nonlinear processes in ultrathin van der Waals materials
Abstract Understanding and controlling nonlinear processes is crucial for engineering light-matter interaction and generating non-classical light. A significant challenge in ultra-thin nonlinear materials is the marked diminution of the nonlinear conversion efficiency due to the reduced light-matter interaction length and, in many cases, the centrosymmetric crystalline structures. Here we relax these limitations and report a giant boost of classical and quantum nonlinear processes in ultrathin van der Waals materials. Specifically, with a metal-nonlinear material heterostructure we enhance classical second-harmonic generation in h-BN flakes by two orders of magnitude. Moreover, we have engineered a metal-SiO2-nonlinear material heterostructure resulting in a remarkable two orders of magnitude augmentation of the quantum spontaneous parametric down-conversion (SPDC) in NbOCl2 flakes. Notably, we demonstrate SPDC in a 16 nm-thick NbOCl2 flake integrated into the proposed structure. These findings simplify on-chip quantum state engineering and accelerate the use of van der Waals materials in nonlinear optoelectronics.
Axial collapse behavior of stainless steel circular tubes with thin walls in diamond mode
Undermining a PACT — Federal Cuts at the VA
Quantum dot LEDs emitting broadband vortex beams
Abstract The past few years have witnessed impressive developments in optical sources capable of emitting structured forms of light, such as optical vortices or vector beams. Because structured beams result from carefully engineered interferences, their synthesis requires coherent light and all the sources demonstrated so far rely on coherent lasing cavities—usually pumped with external optical schemes. Here, we introduce non-lasing sources emitting directional vortex beams upon electrical injection. Their architecture consists of colloidal PbS quantum dot LEDs that integrate a photonic environment with two complementary functions: to make the emitters populate radial photonic modes with extended spatial coherence, and to structure the leakage of these modes into free space. Our electrically-pumped sources exhibit phase singularities across the electroluminescence spectrum of the quantum dots, leading to vortex light emission with a bandwidth of 300 nm in the near-infrared.
Structural elastic and thermodynamic properties of cubic CsCl type MgCa using ab initio approach
Identification and Treatment of Alcohol Use Disorder
Structure and assembly of the MmpL5/MmpS5 efflux transporter from Mycobacterium tuberculosis
Population-based estimates of different dosage types of psychedelic use across socio-demographic groups in Germany
Abstract Psychedelic drugs, particularly taking small amounts of psychedelics in a cyclical pattern over days (so-called microdosing), have garnered growing scientific and public interest, but representative data on different dosage levels is scarce. To better understand this trend, we surveyed a nationwide sample of 11,299 adults in Germany. The survey assessed lifetime and past six-month psychedelic use by dosage as well as socio-demographic variables (sex, age, education, employment status, household equivalence income, partner arrangements, and place of residence). Results show that 5.0% of respondents self-reported lifetime psychedelic use, while 0.7% reported past six-month use. Medium to high dosing was more prevalent than microdosing. Moreover, high probabilities of using multiple forms of psychedelics were uncovered. We also observed variation in use across socio-demographic groups. For example, psychedelics use was less likely in females than males, and older than younger respondents. Past six-month microdosing was less likely in rural areas, and past six-month medium to high dosing was less prevalent in individuals with higher income or who live with a partner. This study shows limited support for widespread use in Germany and highlights diverse usage patterns across socio-demographics. These findings can inform policies, especially considering the overlap in usage of various substances.
Tufted Angioma with Kasabach–Merritt Phenomenon
Impacts of leaf traits on vegetation optical properties in Earth system modeling
Correlations between pain, functioning, and quality of life in manual wheelchair users with spinal cord injury
Background Pain after spinal cord injury (SCI) is one of the most important contributors to poor rehabilitation outcomes, reduced quality of life (QOL) as well as poorer physical, social, and psychological functioning. Objective To determine the correlation of overall and shoulder pain on functioning and QOL in community-dwelling people with SCI. Methods This quantitative correlational study included people with SCI with or without pain, who were discharged from five rehabilitation hospitals in Gauteng, South Africa. The presence of pain, wheelchair function, and QOL were investigated using the Numeric Rating Scale, Wheelchair Function Test Questionnaire, and the WHOQOL-BREF questionnaire. Pectoralis minor muscle (PMm) length was measured using a Vernier caliper and the Scapular Dyskinesis test was used to observe for scapular dyskinesis. Descriptive statistics; Independent t-tests, ANOVA tests, and Fisher’s exact tests were performed using the SPSS v27 at a 0.05 level of significance. Results 85% of the 122 participants reported overall pain, mainly burning (32.7%) and below the level of injury (39.4%), with only 14.8% reporting shoulder pain. There was no overall difference in QOL between participants with and without pain, however, pain prevented individuals from doing what they needed to do (p < 0.05). Pain severity was negatively correlated with QOL (p < 0.001) and sleep satisfaction (p < 0.05). There were no correlations found between shoulder pain and PMm length, as well as scapular dyskinesis. However, there was a negative correlation between shoulder pain and wheelchair function in those who reported shoulder pain (p < 0.01). Conclusion Pain is problematic after SCI and although shoulder pain is not as prominent, it has the potential to negatively impact an individual’s ability to use their wheelchair effectively. Contribution Findings from this study emphasise the negative role of pain on life satisfaction and QOL. Stakeholders involved in SCI rehabilitation can consider including comprehensive pain management within the interprofessional model of care.
Transcriptomic response of marine dinoflagellate Prorocentrum cordatum to phosphorus deficiency
The Meaning of Goodbye
Lunar dichotomy in surface water storage of impact glass beads
Initial coral assemblage drives benthic community response to different disturbance type events
An increase in the intensity and frequency of extreme environmental conditions due to anthropogenic climate change impacts coral reefs through myriad stressors, from elevated sea-surface temperatures to increased storm activity. A reef’s response to these disturbances can be influenced by factors including taxonomic composition, life history strategies, or spatial patterning of the reef community members. We explored the disturbance-specific responses of coral reefs by following changes in benthic cover of major functional groups, community assemblage, and the response of common coral taxa at six islands across the central Pacific over the course of two years. We observed a decrease in average coral cover at four of the six islands, with differing underlying shifts in assemblage structure. Reefs with the highest pre-disturbance benthic coverage of Montipora spp. displayed significant increases in average hard coral cover compared to those where Acropora spp. was in the highest abundance; Acropora-dominated reefs showed significant declines in coral cover especially when exposed to the physical stress associated with a cyclone. Change in total coral cover was variable between islands within the same region, even among adjacent islands facing similar disturbance. These results highlight the importance of assemblage composition in influencing how benthic communities respond to major disturbance events such as thermal stress or cyclones. Improving our understanding of the drivers of differential community responses to disturbance will be important in predicting future changes in reef structure under changing ocean conditions.