Neural Point-based Volumetric Avatar: Surface-guided Neural Points for Efficient and Photorealistic Volumetric Head Avatar

Rendering photorealistic and dynamically moving human heads is crucial for ensuring a pleasant and immersive experience in AR/VR and video conferencing applications. However, existing methods often struggle to model challenging facial regions (e.g., mouth interior, eyes, hair/beard), resulting in unrealistic and blurry results. In this paper, we propose {\fullname} ({\name}), a method that adopts the neural point representation as well as the neural volume rendering process and discards the predefined connectivity and hard correspondence imposed by mesh-based approaches. Specifically, the neural points are strategically constrained around the surface of the target expression via a high-resolution UV displacement map, achieving increased modeling capacity and more accurate control. We introduce three technical innovations to improve the rendering and training efficiency: a patch-wise depth-guided (shading point) sampling strategy, a lightweight radiance decoding process, and a Grid-Error-Patch (GEP) ray sampling strategy during training. By design, our {\name} is better equipped to handle topologically changing regions and thin structures while also ensuring accurate expression control when animating avatars. Experiments conducted on three subjects from the Multiface dataset demonstrate the effectiveness of our designs, outperforming previous state-of-the-art methods, especially in handling challenging facial regions

Step pyrolysis of N-rich industrial biowastes: Regulatory mechanism of NOx precursor formation via exploring decisive reaction pathways

Step pyrolysis of N-rich industrial biowastes was used to explore decisive reaction pathways and regulatory mechanisms of NOx precursor formation. Three typical ones involving medium-density fiberboard waste (MFW), penicillin mycelia waste (PMW) and sewage sludge (SS) were employed to compare the formation characteristics of NOx precursors during one-step and two-step pyrolysis. Results demonstrated that considerable NH3-N pre-dominated NOx precursors for one-step pyrolysis at low temperatures, depending on primary pyrolysis of labile amide-N/inorganic-N in fuels. Meanwhile, NOx precursors differed in the increment of each species yield while resembled in the total yield of 20-45 wt.% among three samples at high temperatures, due to specific prevailing reaction pathways linking with distinctive amide-N types. Subsequently, compared with one-step pyrolysis uniformly (800 degrees C), by manipulating intensities of reaction pathways at different stages (selecting differential intermediate feedstocks), two-step pyrolysis was capable of minimizing NOx precursor-N yield by 36-43% with a greater impact on HCN-N (75-85%) than NH3-N (9-37%), demonstrating its great capacity on regulating the formation of NOx precursors for industrial biowaste pyrolysis. These observations were beneficial to develop effective insights into N-pollution emission control during their thermal reutilization

Design and evaluation of a foot-controlled robotic system for endoscopic surgery

In traditional endoscopic surgery, the surgeon manipulating the endoscopic instruments is supported by an assistant controlling the endoscope, where their coordination may be affected by communication errors. To address this issue, we introduce a foot interface controlled robotic endoscopic system, enabling the surgeon to simultaneously operate the endoscope and instruments. The system consists of a foot interface using four degrees of freedom (DoFs) foot gestures and a robotic driving system for a commercial flexible endoscope. The proposed robotic system was validated in teleoperation experiments performed by ten subjects, where foot teleoperation was compared with hand teleoperation and direct control of the endoscope with two hands. The participants could successfully teleoperate the endoscope with foot teleoperation and exhibited 40% faster task completion as with direct control. They found both foot and hand teleoperations comfortable and intuitive. Although hand teleoperation enabled the best performance, only foot teleoperation allows simultaneous control of three instruments.Accepted versio

DreamDiffusion: Generating High-Quality Images from Brain EEG Signals

This paper introduces DreamDiffusion, a novel method for generating high-quality images directly from brain electroencephalogram (EEG) signals, without the need to translate thoughts into text. DreamDiffusion leverages pre-trained text-to-image models and employs temporal masked signal modeling to pre-train the EEG encoder for effective and robust EEG representations. Additionally, the method further leverages the CLIP image encoder to provide extra supervision to better align EEG, text, and image embeddings with limited EEG-image pairs. Overall, the proposed method overcomes the challenges of using EEG signals for image generation, such as noise, limited information, and individual differences, and achieves promising results. Quantitative and qualitative results demonstrate the effectiveness of the proposed method as a significant step towards portable and low-cost ``thoughts-to-image'', with potential applications in neuroscience and computer vision.Comment: 8 pages, 7 figure

Family functioning and patients’ depressive symptoms: comparison in perceived family function between patients who had an acute ischaemic stroke and their primary family caregivers – a cross-sectional study

Objectives This study aims to compare perceived family functioning between Chinese patients who had an acute ischaemic stroke (AIS) and family caregivers, and explore the association between family functioning and patients’ depressive symptoms.Design This is a cross-sectional study design.Setting Stroke centres of two tertiary hospitals in Nanjing, China.Participants One hundred and sixty-nine dyads of patients who had an AIS and family caregivers.Primary and secondary outcome measures Family functioning of patients who had an AIS and their primary family caregivers was assessed by the Family Assessment Device (FAD, Chinese version). Depressive symptoms of patients who had an AIS was assessed by the Centre for Epidemiological Studies Depression Scale. We test the agreement and differences in family functioning. Multivariate linear regression models were used to test the association of differences of family functioning within dyads with patients’ depressive symptoms.Results AIS families demonstrated unhealthy family functioning. A total of 115 patients (76.9%) and 124 caregivers (73.4%) had a score of 2 or higher in FAD-general functioning (GF), indicating unhealthy family functioning. The intraclass correlation coefficient of FAD subdomain between patients who had an AIS and caregivers ranged from 0.15 to 0.55, which indicating the agreement of family functioning within dyads was poor to moderate. There was a significant difference between the FAD-GF scores of the patients and those of their caregivers (Z=−2.631, p=0.009), with caregivers reporting poorer general family functioning. Poor family functioning and greater difference of perceived family functioning within dyads were related to higher level of patients’ depressive symptoms (β=5.163, p<0.001, β=5.534, p<0.001, respectively).Conclusions These findings indicate that healthcare professionals should assess family functioning in both patients who had a stroke and caregivers. Improvement of family function and decreasing discrepancies within dyads may be helpful for relieving patients’ depressive symptoms

Distribution Characteristics and Formation Mechanisms of Highly Mineralized Groundwater in the Hetao Plain, Inner Mongolia

As the largest artesian irrigation area in northern China, the Hetao Plain is also one of the major grain-producing areas in China. Meanwhile, there is a large amount of highly mineralized groundwater resulting in the soil salinization and desertification in this region. In addition, this study also uses the traditional hydro-geochemical methods to investigate the spatial evolution characteristics and formation mechanisms of highly mineralized groundwater. The results indicate that there is a large amount of highly mineralized groundwater (salinity > 3 g/L) in the shallow aquifer over the Hetao Plain. As far as the spatial patterns are concerned, there are significant spatial differences. In accordance with the structural, paleogeographic, landform, and hydrogeological conditions, the highly mineralized groundwater in the Hetao Plain can be divided into five zones, namely, the front fan depression, the north bank of the Yellow River, Xishanzui, Hasuhai in the Hubao Plain, and Dalad banner on the south bank of the Yellow River. Among them, the highly mineralized groundwater of Xishanzui exhibits the largest value of the salinity > 10 g/L. The main cations are Mg2+ and Na+, while the main anions are Cl− and SO42−. Moreover, the groundwater in the highly mineralized area contains a large amount of I−. According to the analysis of Piper, Gibbs diagrams of groundwater, the proportion coefficients of various components and the indication of isotope, it can be seen that most of the chemical ions in groundwater in the highly mineralized zone come from evaporation-concentration, which are mainly affected by climate, sedimentary environment, hydrogeological conditions and hydrology. The source of high mineralization in Xishanzui are different from other high mineralization regions, and the highly mineralized groundwater in Xishanzui is formed by the infestation of deep underground salt brine. These results can provide scientific basis for the rational allocation of regional water resources and the promotion of water resources development and utilization

A subject-specific four-degree-of-freedom foot interface to control a surgical robot

This paper introduces a passive four-degree-of-freedom foot interface to control a robotic surgical instrument. This interface is based on a parallel-serial hybrid mechanism with springs and force sensors. In contrast to existing switch-based interfaces that can command a slave robot arm at constant speeds in only discrete directions, the novel interface provides an operator with intuitive control in continuous directions and speeds with force and position feedback. The output command of the interface was initially derived based on the kinematics and statics of the interface. Since distinct movement patterns among different subjects were observed in a pilot test, a data-driven approach using Independent Component Analysis (ICA) was developed to convert the foot inputs to the control command of the user. The capability of this interface in controlling a robotic arm in multiple degrees of freedom was further verified with a teleoperation test.NRF (Natl Research Foundation, S’pore)Accepted versio

Data_Sheet_1_The moderating effect of cognitive reserve on cognitive function in patients with Acute Ischemic Stroke.pdf

BackgroundRecovery of cognitive function after stroke has inter-individual variability. The theory of cognitive reserve offers a potential explanation of the variability in cognitive function after stroke.ObjectiveThis study aimed to investigate the moderating effect of cognitive reserve on the relationship between the stroke severity and cognitive function after stroke.Materials and methodsA total of 220 patients with Acute Ischemic Stroke (AIS) were recruited in 2021 from two stroke centers in Nanjing, China. The National Institutes of Health Stroke Scale (NIHSS) was used to assess stroke severity upon admission. Cognitive Reserve Index questionnaire (CRIq) and validated Montreal Cognitive Assessment, Changsha Version (MoCA-CS) were used to assess cognitive reserve and cognitive function within 7 days after stroke onset, respectively. A series of multivariate linear regression models were applied to test the moderating effect of cognitive reserve.ResultsPatients with a higher level of cognitive reserve had better cognitive function after stroke compared with those with a lower level of cognitive reserve (β = 0.074, p = 0.003). The interaction of NIHSS and cognitive reserve was statistically significant (β = −0.010, p = 0.045) after adjusting for some key covariates [e.g., age, marital status, Oxfordshire Community Stroke Project (OCSP) classification, Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification, cerebral vascular stenosis, diabetes and atrial fibrillation].ConclusionCognitive reserve may help to buffer the effect of stroke-related pathology on cognitive decline in Chinese acute stroke patients. Enhancing cognitive reserve in stroke patients may be one of the potential strategies for preventing vascular dementia.</p