Psb28 protein is indispensable for stable accumulation of PSII core complexes in Arabidopsis.

Enhancing the efficiency of photosynthesis represents a promising strategy to improve crop yields, with keeping the steady state of PSII being key to determining the photosynthetic performance. However, the mechanisms whereby the stability of PSII is maintained in oxygenic organisms remain to be explored. Here, we report that the Psb28 protein functions in regulating the homeostasis of PSII under different light conditions in Arabidopsis thaliana. The psb28 mutant is much smaller than the wild-type plants under normal growth light, which is due to its significantly reduced PSII activity. Similar defects were seen under low light and became more pronounced under photoinhibitory light. Notably, the amounts of PSII core complexes and core subunits are specifically decreased in psb28, whereas the abundance of other representative components of photosynthetic complexes remains largely unaltered. Although the PSII activity of psb28 was severely reduced when subjected to high light, its recovery from photoinactivation was not affected. By contrast, the degradation of PSII core protein subunits is dramatically accelerated in the presence of lincomycin. These results indicate that psb28 is defective in the photoprotection of PSII, which is consistent with the observation that the overall NPQ is much lower in psb28 compared to the wild type. Moreover, the Psb28 protein is associated with PSII core complexes and interacts mainly with the CP47 subunit of PSII core. Taken together, these findings reveal an important role for Psb28 in the protection and stabilization of PSII core in response to changes in light environments.

Vapor Phase Growth of Air-Stable Hybrid Perovskite FAPbBr3 Single-Crystalline Nanosheets.

Organic-inorganic hybrid perovskites have attracted tremendous attention owing to their fascinating optoelectronic properties. However, their poor air stability seriously hinders practical applications, which becomes more serious with thickness down to the nanoscale. Here we report a one-step vapor phase growth of HC(NH2)2PbBr3 (FAPbBr3) single-crystalline nanosheets of tunable size up to 50 µm and thickness down to 20 nm. The FAPbBr3 nanosheets demonstrate high stability for over months of exposure to air with no degradation in surface roughness and photoluminescence efficiency. Besides, the FAPbBr3 photodetectors exhibit superior overall performance as compared to previous devices based on nonlayered perovskite nanosheets, such as an ultralow dark current of 24 pA, an ultrahigh responsivity of 1033 A/W, an external quantum efficiency over 3000%, a rapid response time around 25 ms, and a high on/off ratio of 104. This work provides a strategy to tackle the challenges of hybrid perovskites toward integrated optoelectronics with requirements of nanoscale thickness, high stability, and excellent performance.

Diamond-Reinforced Al(H2PO4)3@Epoxy Hybrid Thermal Adhesive With Ultra-High Thermal Conductivity and Bonding Strength.

The miniaturization, integration, and increased power of electronic devices have exacerbated serious heat dissipation issues. Thermally conductive adhesives, which effectively transfer heat and firmly bond components, are critical for addressing these challenges. This paper innovatively proposed a composite comprising inorganic phosphate/alumina as a matrix and diamond as filler. The composite achieved an isotropic thermal conductivity (TC) of up to 18.96 W m-1 K-1, significantly surpassing existing reports while maintaining electrical insulation. First-principles calculations and experimental tests confirmed that the high TC of phosphate and excellent interface contact ensured efficient heat transfer. To optimize bonding performance, a modified-diamond/Al(H2PO4)3@epoxy hybrid composite is subsequently developed using an organic modification method. The unique hybrid structure, combining inorganic thermal pathways and an organic adhesive network, enabled the hybrid composite to simultaneously possess a high TC (3.23 W m-1 K-1) and strong adhesion (14.35 MPa). Compared to previous reports, the comprehensive performance of this hybrid thermally conductive adhesive is exceptionally remarkable. The superior heat dissipation capability of the hybrid thermal adhesive is demonstrated in chip cooling scenarios. This organic/inorganic hybrid approach offered a new direction for obtaining advanced thermal interface materials, demonstrating significant application potential in chip soldering, packaging, and heat dissipation.

2D Tungsten Borides Induced Interfacial Modulation Engineering Toward High-Rate Performance Zinc-Iodine Battery.

Aqueous zinc-iodine batteries are promising candidates for large-scale energy storage due to their high energy density and low cost. However, their development is hindered by several drawbacks, including zinc dendrites, anode corrosion, and the shuttle of polyiodides. Here, the design of 2D-shaped tungsten boride nanosheets with abundant borophene subunits-based active sites is reported to guide the (002) plane-dominated deposition of zinc while suppressing side reactions, which facilitates interfacial nucleation and uniform growth of zinc. Meanwhile, the interfacial d-band orbits of tungsten sites can further enhance the anchoring of polyiodides on the surface, to promote the electrocatalytic redox conversion of iodine. The resulting tungsten boride-based I2 cathodes in zinc-iodine cells exhibit impressive cyclic stability after 5000 cycles at 50 C, which accelerates the practical applications of zinc-iodine batteries.

Altitudinal patterns of alpine soil ammonia-oxidizing community structure and potential nitrification rate.

Nitrogen availability limits the net primary productivity in alpine meadows on the Qinghai-Tibetan Plateau, which is regulated by ammonia-oxidizing microorganisms. However, little is known about the elevational patterns of soil ammonia oxidizers in alpine meadows. Here, we investigated the potential nitrification rate (PNR), abundance, and community diversity of soil ammonia-oxidizing microorganisms along the altitudinal gradient between 3,200 and 4,200 m in Qinghai-Tibetan alpine meadows. We found that both PNR and amoA gene abundance declined from 3,400 to 4,200 m but lowered at 3,200 m, possibly due to intense substrate competition and biological nitrification inhibition from grasses. The primary contributors to soil nitrification were ammonia-oxidizing archaea (AOA), and their proportionate share of soil nitrification increased with altitude in comparison to ammonia-oxidizing bacteria (AOB). The alpha diversity of AOA increased by higher temperature and plant richness at low elevations, while decreased by higher moisture and low legume biomass at middle elevations. In contrast, the alpha diversity of AOB increased along elevation. The elevational patterns of AOA and AOB communities were primarily driven by temperature, soil moisture, and vegetation. These findings suggest that elevation-induced climate changes, such as shifts in temperature and water conditions, could potentially alter the soil nitrification process in alpine meadows through changes in vegetation and soil properties, which provide new insights into how soil ammonia oxidizers respond to climate change in alpine meadows.IMPORTANCEThe importance of this study is revealing that elevational patterns and nitrification contributions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) communities were primarily driven by temperature, soil moisture, and vegetation. Compared to AOB, the relative contribution of AOA to soil nitrification increased at higher elevations. The research highlights the potential impact of elevation-induced climate change on nitrification processes in alpine meadows, mediated by alterations in vegetation and soil properties. By providing new insights into how ammonia oxidizers respond to climate change, this study contributes valuable knowledge to the field of microbial ecology and helps predict ecological responses to environmental changes in alpine meadows.

An intrinsically disordered region-containing protein mitigates the drought-growth trade-off to boost yields.

Drought stress poses a serious threat to global agricultural productivity and food security. Plant resistance to drought is typically accompanied by a growth deficit and yield penalty. Herein, we report a previously uncharacterized, dicotyledon-specific gene, Stress and Growth Interconnector (SGI), that promotes growth during drought in the oil crop rapeseed (Brassica napus) and the model plant Arabidopsis (Arabidopsis thaliana). Overexpression of SGI conferred enhanced biomass and yield under water-deficient conditions, whereas corresponding CRISPR SGI mutants exhibited the opposite effects. These attributes were achieved by mediating reactive oxygen species (ROS) homeostasis while maintaining photosynthetic efficiency to increase plant fitness under water-limiting environments. Further spatial-temporal transcriptome profiling revealed dynamic reprogramming of pathways for photosynthesis and stress responses during drought and the subsequent recovery. Mechanistically, SGI represents an intrinsically disordered region-containing protein that interacts with itself, catalase isoforms, dehydrins, and other drought-responsive positive factors, restraining ROS generation. These multifaceted interactions stabilize catalases in response to drought and facilitate their ROS-scavenging activities. Taken altogether, these findings provide insights into currently underexplored mechanisms to circumvent trade-offs between plant growth and stress tolerance that will inform strategies to breed climate-resilient, higher yielding crops for sustainable agriculture.

Immune modulation in malignant pleural effusion: from microenvironment to therapeutic implications.

Immune microenvironment and immunotherapy have become the focus and frontier of tumor research, and the immune checkpoint inhibitors has provided novel strategies for tumor treatment. Malignant pleural effusion (MPE) is a common end-stage manifestation of lung cancer, malignant pleural mesothelioma and other thoracic malignancies, which is invasive and often accompanied by poor prognosis, affecting the quality of life of affected patients. Currently, clinical therapy for MPE is limited to pleural puncture, pleural fixation, catheter drainage, and other palliative therapies. Immunization is a new direction for rehabilitation and treatment of MPE. The effusion caused by cancer cells establishes its own immune microenvironment during its formation. Immune cells, cytokines, signal pathways of microenvironment affect the MPE progress and prognosis of patients. The interaction between them have been proved. The relevant studies were obtained through a systematic search of PubMed database according to keywords search method. Then through screening and sorting and reading full-text, 300 literatures were screened out. Exclude irrelevant and poor quality articles, 238 literatures were cited in the references. In this study, the mechanism of immune microenvironment affecting malignant pleural effusion was discussed from the perspectives of adaptive immune cells, innate immune cells, cytokines and molecular targets. Meanwhile, this study focused on the clinical value of microenvironmental components in the immunotherapy and prognosis of malignant pleural effusion.

Comparative analysis of the quality of platelet concentrates produced by apheresis procedures, platelet rich plasma, and buffy coat.

BACKGROUND: Platelet concentrates (PCs) could be prepared using either whole-blood processes or apheresis instruments. During collection, processing and storage, some biochemical and functional changes occur, which may result in quality reduction. Quality evaluation of PCs may be helpful for the precise control of platelet (PLT) inventory to reduce the risk of refractoriness and adverse effects caused by platelet transfusion. STUDY DESIGN AND METHODS: The study was aimed to evaluate the quality of PCs which were produced by five processes: apheresis (AP) procedures (using three different cell separators: Amicus, Trima Accel and MCS+ instruments), platelet rich plasma (PRP), and buffy coat (BC). A total of 100 PCs (20 of each group) were assessed in respect of routine quality control, morphology, size distribution, destroyed and activated platelets, and production of platelet-derived microparticles (PMPs). RESULTS: All PCs have satisfied the recommended quality of volume, platelet count, residual WBC count, residual RBC count, pH, and sterility according to the Chinese Technical Manual. There was no difference among the 5 groups in morphology and size of PLT and PMPs. Dynamic light scattering test showed that apheresis PCs showed peaks around 10-20 nm, but not whole blood-derived PCs. PCs prepared by Amicus had the relatively high percentage of destroyed platelet, activated platelets and PMPs than other groups. DISCUSSION: The data suggested high heterogeneity of PMPs, destroyed and activated platelets in PCs produced by different processes, which might be helpful to manage the platelet inventory for targeted use.

First report of Botrytis cinerea causing gray mold on Alternanthera philoxeroides in China.

Alternanthera philoxeroides is a perennial herbaceous plant used as a forage crop (Wang et al. 2005) and is known to have medicinal properties. One of notable active components is flavonoids, which have been found to exhibit anti-Hepatitis B Virus activity (Li et al. 2016). In 2021, a leaf spot on A. philoxeroides was observed in the science and education experimental park of Hebei Agricultural University (38°49'38″ N, 115°26'39″ E). Initial symptoms included leaf tissue water loss, chloro-sis and elliptical lesions scattered across the leaf margin with further development leading to ellipse-shaped disease spots and leaf wilting (Fig. 1A). In the field, 50 plants of A. philoxeroides were randomly selected to investigate and quantify dis-ease. Incidence of leaf disease was approximately 25%, and the infected leaves ex-hibited an average affected area of about 20%. In order to identify the pathogen, three diseased plants were randomly selected from different areas. Stems and leaves of diseased plants were cut into pieces (2 to 3 mm × 5 mm) and disinfested with 1% sodium hypochlorite for 1 minute. After rinsing with sterile water three times, each lesion sample was isolated and purified on PDA at 25°C. Eventually, all samples pro-duced morphologically consistent colonies of pure strains. From the 9 isolates ob-tained, ZLQ-1 was selected as a representative isolate for further study. Colonies were initially white, turning gray from the centre, then gray-brown with cottony aerial hyphae, and finally growing black, stiff, round or irregular sclerotia (0.6 to 4.0 mm × 1.1 to 4.2 mm, n=50) (Fig1. B, C). ZLQ-1 exhibited branched conidia with en-larged apical cells. The conidia of this isolate were unicellular, ovoid or ellipsoid in shape, with dimensions ranging from 5.8 to 16.9 µm × 6.3 to 11.2 µm (n=50) (Fig. 1D). These morphological characteristics were consistent with Botrytis cinerea (Ellis, 1971). The genes of internal transcribed spacer (ITS), heat shock protein (HSP60), DNA-dependent RNA polymerase subunit II (RPB2), and glyceraldehyde-3-phosphate dehydrogenase (G3PDH) were amplified with specific primers ITS1/ITS4, HSP60-F/HSP60-R, RPB2-F/RPB2-R and G3PDH-F/G3PDH-R (Aktaruzzaman et al., 2022). Sequences were deposited into GenBank with accession numbers ON479490 for ITS, ON572246 for G3PDH, ON572248 for HSP60, ON572247 for RPB2. BLASTn analysis showed that the ITS sequence shared 99.62% similarity to B. cinerea (CP009808), and the sequences of the other three nuclear protein-encoding genes (G3PDH, HSP60, and RPB2) showed at least 99.9% identity with the genome of B. ci-nerea (B05.10) (Staats et al. 2005). We have inoculated 10 healthy A. philoxeroides leaves with a suspension of 1x105 spores/mL, and used sterile water treatment as control (Aktaruzzaman et al., 2022). Each leaf was inoculated with 10 µL spore sus-pension. After 7 days in a controlled incubation environment (25℃, 40%RH), the plants inoculated with conidial suspensions displayed lesions covered in a gray-white mycelial layer, resembling those observed in the field (Fig. 1E-G). In con-trast, the plants inoculated with sterile water remained unaffected. Morphological and PCR analysis confirmed that the pathogen responsible for the observed symp-toms was B. cinerea. Koch's postulates were fulfilled as the same pathogen was con-sistently re-isolated from the inoculated leaves and confirmed to be B. cinerea through morphological and molecular methods. This is the first reported case of B. cinerea causing gray mold on A. philoxeroides in China. It is important to monitor and prevent B. cinerea infection during cultivation to ensure the production of healthy Chinese medicine and feed.

Electrical Sensor Calibration by Fuzzy Clustering with Mandatory Constraint.

Electrical tomography sensors have been widely used for pipeline parameter detection and estimation. Before they can be used in formal applications, the sensors must be calibrated using enough labeled data. However, due to the high complexity of actual measuring environments, the calibrated sensors are inaccurate since the labeling data may be uncertain, inconsistent, incomplete, or even invalid. Alternatively, it is always possible to obtain partial data with accurate labels, which can form mandatory constraints to correct errors in other labeling data. In this paper, a semi-supervised fuzzy clustering algorithm is proposed, and the fuzzy membership degree in the algorithm leads to a set of mandatory constraints to correct these inaccurate labels. Experiments in a dredger validate the proposed algorithm in terms of its accuracy and stability. This new fuzzy clustering algorithm can generally decrease the error of labeling data in any sensor calibration process.

Steering sp-Carbon Content in Graphdiynes for Enhanced Two-Electron Oxygen Reduction to Hydrogen Peroxide.

Compared to sp2-hybridized graphene, graphdiynes (GDYs) composed of sp and sp2 carbon are highly promising as efficient catalysts for electrocatalytic oxygen reduction into oxygen peroxide because of the high catalytic reactivity of the electron-rich sp-carbon atoms. The desired catalytic capacity of GDY, such as catalytic selectivity and efficiency, can theoretically be achieved by strategically steering the sp-carbon contents or the topological arrangement of the acetylenic linkages and aromatic bonds. Herein, we successfully tuned the electrocatalytic activity of GDYs by regulating the sp-to-sp2 carbon ratios with different organic monomer precursors. As the active sp-carbon atoms possess electron-sufficient π orbitals, they can donate electrons to the lowest unoccupied molecular orbital (LUMO) orbitals of O2 molecules and initiate subsequent O2 reduction, GDY with the high sp-carbon content of 50 at % exhibits excellent capability of catalyzing O2 reduction into H2O2. It demonstrates exceptional H2O2 selectivity of over 95.0 % and impressive performance in practical H2O2 production, Faraday efficiency (FE) exceeding 99.0 %, and a yield of 83.3 nmol s-1 cm-2. Our work holds significant importance in effectively steering the inherent properties of GDYs by purposefully adjusting the sp-to-sp2 carbon ratio and highlights their immense potential for research and applications in catalysis and other fields.

Low-Concentration Redox-Electrolytes for High-Rate and Long-Life Zinc Metal Batteries.

The uncontrolled zinc electrodeposition and side reactions severely limit the power density and lifespan of Zn metal batteries. Herein, the multi-level interface adjustment effect is realized with low-concentration redox-electrolytes (0.2 m KI) additives. The iodide ions adsorbed on the zinc surface significantly suppress water-induced side reactions and by-product formation and enhance the kinetics of zinc deposition. The distribution of relaxation times results reveal that iodide ions can reduce the desolvation energy of hydrated zinc ions and guide the deposition of zinc ions due to their strong nucleophilicity. As a consequence, the Zn||Zn symmetric cell achieves superior cycling stability (>3000 h at 1 mA cm-2 , 1 mAh cm-2 ) accompanied by a uniform deposition and a fast reaction kinetics with a low voltage hysteresis (<30 mV). Additionally, coupled with an activated carbon (AC) cathode, the assembled Zn||AC cell delivers a high-capacity retention of 81.64% after 2000 cycles at 4 A g-1 . More importantly, the operando electrochemical UV-vis spectroscopies show that a small number of I3 - can spontaneously react with the dead zinc as well as basic zinc saltsand regenerate iodide ions and zinc ions; thus, the Coulombic efficiency of each charge-discharge process is close to 100%.

The Loss-Function of KNL1 Causes Oligospermia and Asthenospermia in Mice by Affecting the Assembly and Separation of the Spindle through Flow Cytometry and Immunofluorescence.

KNL1 (kinetochore scaffold 1) has attracted much attention as one of the assembly elements of the outer kinetochore, and the functions of its different domains have been gradually revealed, most of which are associated with cancers, but few links have been made between KNL1 and male fertility. Here, we first linked KNL1 to male reproductive health and the loss-function of KNL1 resulted in oligospermia and asthenospermia in mice (an 86.5% decrease in total sperm number and an 82.4% increase in static sperm number, respectively) through CASA (computer-aided sperm analysis). Moreover, we introduced an ingenious method to pinpoint the abnormal stage in the spermatogenic cycle using flow cytometry combined with immunofluorescence. Results showed that 49.5% haploid sperm was reduced and 53.2% diploid sperm was increased after the function of KNL1 was lost. Spermatocytes arrest was identified at the meiotic prophase I of spermatogenesis, which was induced by the abnormal assembly and separation of the spindle. In conclusion, we established an association between KNL1 and male fertility, providing a guide for future genetic counseling regarding oligospermia and asthenospermia, and a powerful method for further exploring spermatogenic dysfunction by utilizing flow cytometry and immunofluorescence.

[Analysis of clinical features and genetic variant in a neonate with Au-Kline syndrome due to a de novo variant of the HNRNPK gene].

OBJECTIVE: To explore the clinical phenotype and genetic basis of a neonate with Au-Kline syndrome (AKS). METHODS: Clinical data and result of genetic testing of a neonate with AKS who was admitted to the Affiliated Provincial Children's Hospital of Anhui Medical University in January 2021 were retrospectively analyzed. Relevant literature was searched from the Wanfang Data Knowledge Service Platform, China National Knowledge Infrastructure and PubMed databases using key words "Au Kline syndrome", "Au-Kline syndrome", "HNRNPK" and "AKS". The research period was set as from January 1, 2000 to December 31, 2020. RESULTS: The male newborn has manifested feeding difficulties, hypotonia, absence of the upper jaw to the uvula and facial dysmorphism. Trio-whole exome sequencing revealed that he has harbored a frameshift c.478dupA (p.Ile160AsnfsTer7) variant of the HNRNPK gene, which was varified by Sanger sequencing to have a de novo origin. The variant has not been included in the databases. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was rated as pathogenic (PVS1+PS2+PM2_Supporting). Literature retrieval has identified 14 children with AKS and de novo mutations of the HNRNPK gene. Their clinical manifestations have included growth and motor retardation, various degree of mental retardation, facial dysmorphism and a high frequency of congenital heart malformations. CONCLUSION: The AKS in this child may be attributed to the c478dupA frameshifting variant of the HNRNPK gene. Diagnosis of AKS should be suspected for children with mental retardation and multiple congenital malformation syndromes including Kabuki syndrome.

Multi-mitigation strategies in medical supplies for epidemic outbreaks.

The outbreak of Coronavirus disease 2019 (COVID-19) highlights the importance of sufficient medical supplies stockpiling at the pre-event stage. In contrast, the potential disadvantages of maintaining adequate items at strategic locations (i.e., reserves) are considerable inventory-related costs. Unpredicted demand leads to a high degree of uncertainty. Efforts to mitigate the uncertainty should rely not only on prepositioning supplies at reserves but also on integrating various channels of medical materials. This paper proposes multi-mitigation strategies in medical supplies to ensure uninterrupted supply for hospitals and significant savings by introducing two-type suppliers, reserving and manufacturing suppliers. Thus, each hospital with uncertain demand is enabled to be served by various channels during pandemics: prepositioning in reserves, backups served by reserving suppliers, and medical commodities produced by manufacturing suppliers. Stochasticity is also incorporated into the raw materials available to produce. This research aims to develop an emergency response application that integrates preparedness action (reserve location, inventory level, and contract supplier's selection) with post-event operations (allocating medical materials from various channels). We formulate a two-stage stochastic mixed integer program to determine prepositioning strategy, including two-type suppliers' selection, and post-event allocation of multiple sources. A branch-and-Benders-cut method is developed for this problem and significantly outperforms both the classical Benders decomposition and Gurobi in the solution time. Different-sized test instances also verify the robustness of the proposed method. Based on a realistic and typical case study (inspired by the COVID-19 pandemic in Wuhan, China), significant savings, an increase in inventory utilization and an increase in demand fulfilment are obtained by our approach.

H2 -Inhibited Organic Anodes for Fast and Long-Life Aqueous Aluminum Ion Batteries with a 3.5-Month Calendar Life.

Aqueous aluminum ion batteries are rarely constructed due to the unworkable Al metal and the preferential H2 evolution. Herein, organic anode with H2 -inhibition is optimized through tuning the polymerization degree and displays a high-rate and reversible storage of Al ions based on an enolation between Al ions and the carbonyl double bonds on the conjugated structures. The superiority of the optimal sample is researched, which is attributed to the raised state of lowest unoccupied molecule orbital (LUMO) with the doner N-N bridge and relatively small steric hindrance of the dimmer. When paired with active carbon, a high cycling life of 5000 cycles with a retention of 99.2% is obtained. A full battery constructed by this dimer and δ-MnO2 cathode delivers an average voltage of 1.0 V, high capacity of 263.8 mAh g-1 based on the mass of δ-MnO2 , and high-capacity retention of 88.8% after cycling for 300 cycles. More importantly, with a fully eliminated corrosion and passivation in AlCl3 and Al2 (SO4 )3 electrolytes, a long calendar stability of 104 days is achieved.

Controllable high-speed rotated femtosecond cylindrical vector beam based on optical heterodyne interference.

Structured light beams that possess unique polarization distribution could offer a new degree of freedom for a variety of applications, and hence its flexible polarization manipulation is necessary. Here we experimentally report a heterodyne interference-based method for generating femtosecond cylindrical vector beam (CVB) with high-speed controllable rotated polarization states. The femtosecond CVBs are created through the superposition of two optical vortices with opposite handedness. The use of two acoustic-optical modulators (AOMs) with frequency differences allows to achieve polarization rotation in a hopping-free scheme at on demand speed. Up to 1 MHz of the rotation frequency is demonstrated by visualizing the fast rotation events through a fast-frame-rate CCD camera. Moreover, we show our method can be readily extended to produce higher order CVBs with more complex rotated polarization distributions. Such a simple yet versatile femtosecond polarization-controlled laser system has the capability to act as a nonlinear trapping platform, thus opening tremendous potential opportunities in the fields of micromachining, nanofabrication, and so force.

Bispectral phasor imaging using continuous-wave time-of-flight camera for scattering-scene depth recovery.

In scattering scenes, depth measurements are greatly distorted due to light scattering for Time-of-flight imaging. We propose a bispectral Time-of-flight system and phasor-based depth-recovery method to improve the quality of depth maps in scattering scenes. We reveal that the amplitude of scattered light is wavelength dependent while the phase measured is wavelength independent. The method uses bispectral measurements to nullify the effects of scattering components by calculating the amplitude ratio of scattering phasors. Experimental results demonstrate that the proposed method has a significant improvement in depth recovery with robustness and low computational cost.

Altitudinal niches of symbiotic, associative and free-living diazotrophs driven by soil moisture and temperature in the alpine meadow on the Tibetan Plateau.

Legume-associated symbiotic diazotrophs contribute more to nitrogen (N) fixation than non-symbiotic diazotrophs in many terrestrial ecosystems. However, the percentage of legume biomass is low in alpine meadows on the Tibetan Plateau. Therefore, non-symbiotic diazotrophs may play important roles in N fixation in alpine meadow soils. Moreover, Tibetan alpine meadows are fragile and sensitive to global climate change, and the investigating of the key factor driving soil diazotrophic community still entails several challenges. To address these issues, we investigated diazotrophic spatial distribution and diversity along the elevational gradient between 3200 and 4200 m in the alpine meadow using amplicon sequencing of nifH gene. The result clearly showed that soil moisture and temperature were key factors driving soil diazotrophic community structures. Both altitude and soil depth significantly differentiated diazotrophic community composition. Alpha diversity indices of diazotrophic communities showed unimodal distribution along elevation gradient, strongly affected by soil moisture. Altitudinal niches were occupied by different diazotrophs. Soils at lower elevations were dominated by symbiotic diazotrophs and associative diazotrophs related to high biomass of plant hosts, while those at higher elevations were dominated by free-living psychrophiles such as Polaromonas. Furthermore, high moisture stimulated free-living anaerobes at middle elevations, such as Geobacter and Anaeromyxobacter, while suppressed legumes and symbiotic Mezorhizobium. Soil temperature not only directly affected temperature-sensitive diazotrophs, but also indirectly affected them through plants and soil properties such as pH and ammonium content. Our results suggest that climate change may strongly affect biological nitrogen fixation (BNF), and free-living diazotrophs may play important roles in BNF of alpine meadow system on the Tibetan Plateau.

Polarization-based approach for multipath interference mitigation in time-of-flight imaging.

The existence of nearby obstruction causes significant errors in depth sensing for time-of-flight cameras, namely multipath interference. A polarized time-of-flight system is established for multipath interference mitigation. Based on polarization cues and the phasor representation of time-of-flight imaging, the proposed method acquires depth maps in high accuracy when specular dominant obstruction is in path. Both rough and smooth targets are applicable in our approach even though they have distinct polarization characteristics. Several experiments with different types of targets and various obstructions confirm the effectiveness of our method qualitatively and quantitatively.