See More and Know More: Zero-shot Point Cloud Segmentation via Multi-modal Visual Data

Zero-shot point cloud segmentation aims to make deep models capable of recognizing novel objects in point cloud that are unseen in the training phase. Recent trends favor the pipeline which transfers knowledge from seen classes with labels to unseen classes without labels. They typically align visual features with semantic features obtained from word embedding by the supervision of seen classes' annotations. However, point cloud contains limited information to fully match with semantic features. In fact, the rich appearance information of images is a natural complement to the textureless point cloud, which is not well explored in previous literature. Motivated by this, we propose a novel multi-modal zero-shot learning method to better utilize the complementary information of point clouds and images for more accurate visual-semantic alignment. Extensive experiments are performed in two popular benchmarks, i.e., SemanticKITTI and nuScenes, and our method outperforms current SOTA methods with 52% and 49% improvement on average for unseen class mIoU, respectively.Comment: Accepted by ICCV 202

Variation of peripheral pulse transit time with internal vascular pressure changes induced by arm movement

Pulse transit time (PTT) and blood pressure (BP) are widely used to quantify arterial characteristics. Arm position influences arterial BP and peripheral PTT. This study aims to quantify the relationship between PTT changes with internal vascular pressure variations induced by the arm moving. With left arm at horizontal position as reference and the right arm moving from 90 to 45, 0, −45, and −90° respectively, PTT difference was calculated by the difference of the pulse foot between right arm and left arm within the same heartbeat. The change in the BP was calculated from the gravitational effect with the measured arm length. Our results showed that the change in PTT with arm elevating is more obvious than that with arm lowering, indicating the different relationship between PTT changes due to the internal BP changes. This can help in understanding the inherent physiological/pathological mechanism of cardiovascular system

One step electrochemical fabrication of high performance Ni@Fe-doped Ni(oxy)hydroxide anode for practical alkaline water electrolysis

Oxygen evolution reaction (OER) is a rate-determining process in alkaline water electrolysis (AWE). Herein, we report a novel one-step oxidation-electrodeposition (OSOE) approach to generate core@shell nanoarrays-based AWE electrode with outstanding OER performances: an overpotential of 245 mV at 10 mA cm−2 (Tafel slope: 37 mV dec−1), and excellent stability under huge current densities. Moreover, the alkaline (AEL) cell equipped with NM-OSOE-23 anode recorded significant performance improvement of 200 mV lower voltage (2 A cm−1) compared with a similar cell used bare Ni mesh as an anode, which was contributed by notable enhancements of interface contact, anodic charge transfer, and mass transfer. These promising results are attributed to the constructed specific core@shell Ni@Fe-doped Ni(oxy)hydroxide nanoarray architecture on commercial nickel mesh. This study demonstrates this first reported OSOE can be commercialized to make highly efficient anodes enabling next-generation AWE

Convolutional neural network based on photoplethysmography signals for sleep apnea syndrome detection

IntroductionThe current method of monitoring sleep disorders is complex, time-consuming, and uncomfortable, although it can provide scientifc guidance to ensure worldwide sleep quality. This study aims to seek a comfortable and convenient method for identifying sleep apnea syndrome.MethodsIn this work, a one-dimensional convolutional neural network model was established. To classify this condition, the model was trained with the photoplethysmographic (PPG) signals of 20 healthy people and 39 sleep apnea syndrome (SAS) patients, and the influence of noise on the model was tested by anti-interference experiments.Results and DiscussionThe results showed that the accuracy of the model for SAS classifcation exceeds 90%, and it has some antiinterference ability. This paper provides a SAS detection method based on PPG signals, which is helpful for portable wearable detection

Molecular epidemiology of measles viruses in China, 1995–2003

This report describes the genetic characterization of 297 wild-type measles viruses that were isolated in 24 provinces of China between 1995 and 2003. Phylogenetic analysis of the N gene sequences showed that all of the isolates belonged to genotype H1 except 3 isolates, which were genotype A. The nucleotide sequence and predicted amino acid homologies of the 294-genotype H1 strains were 94.7%–100% and 93.3%–100%, respectively. The genotype H1 isolates were divided into 2 clusters, which differed by approximately 2.9% at the nucleotide level. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Even though other measles genotypes have been detected in countries that border China, this report shows that genotype H1 is widely distributed throughout the country and that China has a single, endemic genotype. This important baseline data will help to monitor the progress of measles control in China

Deep reconstruction of Ni-Al-based pre-catalysts for a highly efficient and durable anion-exchange membrane (AEM) electrolyzer

The anion exchange membrane (AEM) electrolyzer has shown great potential for producing green hydrogen. However, this technology is still in its early stages and has not yet been applied on an industrial scale. One of the most significant challenges is the lack of cost-effective and scalable techniques for producing highly active, durable, and earth-abundant metal-based catalysts. Herein, we present a scalable thermal spraying process for fabricating defect-rich nickel-based HNA-CA that can function as an efficient pre-catalyst for both (hydrogen evolution reaction) HER and (oxygen evolution reaction) OER. Particularly, after deep reconstruction through simple electrochemical activation, the obtained HNA-CA-H and HNA-CA-O exhibit the lowest overpotential of −31 mV (HER) and 188 mV (OER) at 10 mA cm−2, surpassing that of noble metal-based catalysts such as Pt and IrO2, respectively. By coupling two 5 cm2 electrodes, the resulting HNA-CA-H(-)‖HNA-CA-O(+) AEM electrolyzer cell demonstrates exceptional performance, achieving an extraordinarily low cell voltage of 1.89 V at 1 A cm−2 (1 M KOH, room temperature). Furthermore, it showcases remarkable durability, sustaining operation for an impressive 500 hours at 5 A (1 A cm−2). These performance metrics notably outclass the majority of AEM electrolyzers reported under comparable operational settings. The outcomes can primarily be ascribed to the substantial improvements in interfacial contact, charge transfer efficiency, and mass transport mechanisms, all of which were comprehensively unveiled through in situ impedance analysis, ex situ structural characterization, and a thorough investigation of wettability and bubble dynamics. These findings hold significant promise for expediting the advancement and practical deployment of AEM electrolysis technology.</p

Deep reconstruction of Ni-Al-based pre-catalysts for a highly efficient and durable anion-exchange membrane (AEM) electrolyzer

The anion exchange membrane (AEM) electrolyzer has shown great potential for producing green hydrogen. However, this technology is still in its early stages and has not yet been applied on an industrial scale. One of the most significant challenges is the lack of cost-effective and scalable techniques for producing highly active, durable, and earth-abundant metal-based catalysts. Herein, we present a scalable thermal spraying process for fabricating defect-rich nickel-based HNA-CA that can function as an efficient pre-catalyst for both (hydrogen evolution reaction) HER and (oxygen evolution reaction) OER. Particularly, after deep reconstruction through simple electrochemical activation, the obtained HNA-CA-H and HNA-CA-O exhibit the lowest overpotential of −31 mV (HER) and 188 mV (OER) at 10 mA cm−2, surpassing that of noble metal-based catalysts such as Pt and IrO2, respectively. By coupling two 5 cm2 electrodes, the resulting HNA-CA-H(-)‖HNA-CA-O(+) AEM electrolyzer cell demonstrates exceptional performance, achieving an extraordinarily low cell voltage of 1.89 V at 1 A cm−2 (1 M KOH, room temperature). Furthermore, it showcases remarkable durability, sustaining operation for an impressive 500 hours at 5 A (1 A cm−2). These performance metrics notably outclass the majority of AEM electrolyzers reported under comparable operational settings. The outcomes can primarily be ascribed to the substantial improvements in interfacial contact, charge transfer efficiency, and mass transport mechanisms, all of which were comprehensively unveiled through in situ impedance analysis, ex situ structural characterization, and a thorough investigation of wettability and bubble dynamics. These findings hold significant promise for expediting the advancement and practical deployment of AEM electrolysis technology.</p

A novel multi-channel porous structure facilitating mass transport towards highly efficient alkaline water electrolysis

An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis (AWE) efficiency by optimizing the mass transport mechanisms. This effect becomes even more pronounced when aiming to achieve elevated current densities. Herein, we employed a rapid and scalable laser texturing process to craft novel multi-channel porous electrodes. Particularly, the obtained electrodes exhibit the lowest Tafel slope of 79 mV dec−1 (HER) and 49 mV dec−1 (OER). As anticipated, the alkaline electrolyzer (AEL) cell incorporating multi-channel porous electrodes (NP-LT30) exhibited a remarkable improvement in cell efficiency, with voltage drops (from 2.28 to 1.97 V) exceeding 300 mV under 1 A cm−1, compared to conventional perforated Ni plate electrodes. This enhancement mainly stemmed from the employed multi-channel porous structure, facilitating mass transport and bubble dynamics through an innovative convection mode, surpassing the traditional convection mode. Furthermore, the NP-LT30-based AEL cell demonstrated exceptional durability for 300 h under 1.0 A cm−2. This study underscores the capability of the novel multi-channel porous electrodes to expedite mass transport in practical AWE applications.</p