Carbon slow-release and enhanced nitrogen removal performance of plant residue-based composite filler and ecological mechanisms in constructed wetland application.

Stable carbon release and coupled microbial efficacy of external carbon source solid fillers are the keys to enhanced nitrogen removal in constructed wetlands. The constructed wetland plant residue Acorus calamus was cross-linked with poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) to create composite solid carbon source fillers (Ac-BDPs). The study demonstrated the slow release of carbon sources from Ac-BDPs with 35.27 mg/g under an average release rate of 0.88 mg/(g·d). Excellent denitrification was also observed in constructed wetlands with Ac-BDPs. Moreover, the average removal rate of nitrate nitrogen (NO3--N) was increased by 1.94 and 3.85 times of the blank groups under initial NO3--N inputs of 5 and 15 mg/L, respectively. Furthermore, the relatively high abundances of nap, narG, nirKS, norB, qnorZ and nosZ guaranteed efficient denitrification performance in constructed wetlands with Ac-BDPs. The study introduced a reliable technique for biological nitrogen removal by using composite carbon source fillers in constructed wetlands.

A robotic system for transthoracic puncture of pulmonary nodules based on gated respiratory compensation.

BACKGROUND AND OBJECTIVE: With the urgent demands for rapid and precise localization of pulmonary nodules in procedures such as transthoracic puncture biopsy and thoracoscopic surgery, many surgical navigation and robotic systems are applied in the clinical practice of thoracic operation. However, current available positioning methods have certain limitations, including high radiation exposure, large errors from respiratory, complicated and time-consuming procedures, etc. METHODS: To address these issues, a preoperative computed tomography (CT) image-guided robotic system for transthoracic puncture was proposed in this study. Firstly, an algorithm for puncture path planning based on constraints from clinical knowledge was developed. This algorithm enables the calculation of Pareto optimal solutions for multiple clinical targets concerning puncture angle, puncture length, and distance from hazardous areas. Secondly, to eradicate intraoperative radiation exposure, a fast registration method based on preoperative CT and gated respiration compensation was proposed. The registration process could be completed by the direct selection of points on the skin near the sternum using a hand-held probe. Gating detection and joint optimization algorithms are then performed on the collected point cloud data to compensate for errors from respiratory motion. Thirdly, to enhance accuracy and intraoperative safety, the puncture guide was utilized as an end effector to restrict the movement of the optically tracked needle, then risky actions with patient contact would be strictly limited. RESULTS: The proposed system was evaluated through phantom experiments on our custom-designed simulation test platform for patient respiratory motion to assess its accuracy and feasibility. The results demonstrated an average target point error (TPE) of 2.46 ± 0.68 mm and an angle error (AE) of 1.49 ± 0.45° for the robotic system. CONCLUSIONS: In conclusion, our proposed system ensures accuracy, surgical efficiency, and safety while also reducing needle insertions and radiation exposure in transthoracic puncture procedures, thus offering substantial potential for clinical application.

Mitogenome analysis reveals predominantly ancient Yellow River origin of population inhabiting Datong agro-pastoral ecotone along Great Wall.

The Datong Basin was an important arena for population movement and admixture between the Yellow River Valley and Eastern Steppe. In historical materials, the region was often the setting for a tug-of-war between Han farmers and non-Han nomads. The genetic makeup and population history of this Datong population has, however, remained uncertain. In this study, we analysed 289 mitogenomes from Datong individuals. Our primary findings were: (1) population summary statistics analysis revealed a high level of genetic diversity and strong signals of population expansion in the Datong population; (2) inter-population comparisons (PCA and Fst heatmap) exhibited a close clustering between the Datong population and Northern Han, especially northern frontier groups, such as the Inner Mongolia Han, Heilongjiang Han, Liaoning Han and Tianjin Han; (3) phylogeographic analysis of complete mitogenomes revealed the presence of different components in the maternal gene pools of Datong population-the northern East Asian component was dominant (66.44%), whereas the southern East Asians were the second largest component with 31.49%. We also observed a much reduced west Eurasian (2.07%) component; (4) direct comparisons with ancient groups showed closer relationship between Datong and Yellow River farmers than Eastern Steppe nomads. Despite, therefore, centuries of Eastern Steppe nomadic control over the Datong area, Yellow River farmers had a much more significant impact on the Datong population.

Occurrence, source apportionment and ecological risk assessment of thirty antibiotics in farmland system.

Antibiotics are widely used in medical care, livestock production, and aquaculture. However, antibiotic pollution has attracted increasing global concerns due to their ecological risks after entering into environmental ecosystem via animal excretion, effulent from industrial and domestic sewage treatment facilities. In this study, 30 antibiotics were investigated in soils and irrigation rivers using ultra-performance liquid chromatography-triple quadrupole tandem mass spectrometer. This study evaluated the occurrence, source apportionment, and ecological risks of these target compounds in soils and irrigation rivers (i.e., sediments and water) of farmland system by using principal component analysis-multivariate linear regression (PCA-MLR) and risk quotients (RQ). The concentration range of antibiotics in soils, sediments, and water was 0.38-689.58 ng/g, 81.99-658.00 ng/g, and 134.45-1547.06 ng/L, respectively. In soils, the most abundant antibiotics were quinolones and antifungals with an average concentration of 30.00 ng/g and 7.69 ng/g, respectively, contributing to 40% of total antibiotics. Macrolides were the most frequently detected antibiotics in soils with an average concentration of 4.94 ng/g. In irrigation rivers, quinolones and tetracyclines, the most abundant antibiotics, accounted for 78% and 65% of antibiotics in water and sediments, respectively. Higher antibiotic contamination of irrigation water was primarily distributed in highly populated urban areas, while increasing antibiotic contamination of sediments and soils was particularly observed in rural areas. PCA-MLR analysis indicated that antibiotic contamination in soils was mainly ascribed to the irrigation of sewage-receiving water body and manure application of livestock and poultry farming, which cumulatively contributed to 76% of antibiotics. According to RQ assessment, quinolones in irrigation rivers posed high risk to algae and daphnia, contributing 85% and 72% to the mixture risk, respectively. In soils, macrolides, quinolones and sulfonamides were responsible for more than 90% to the mixture risk of antibiotics. Ultimately, these findings can improve our fundamental knowledge on contamination characteristics and source pathways towards risk management of antibiotics in farmland system.

Assessing the Foodshed and Food Self-Sufficiency of the Pearl River Delta Megacity Region in China.

Food self-sufficiency has long been regarded as essential for understanding and managing urban and regional food systems; however, few studies have examined the food self-sufficiency of megacity regions within a comprehensive framework that distinguishes different types of agricultural land (i.e., arable land, horticultural landscapes, and waters). To fill these gaps, we took the Pearl River Delta as a case study and quantified the foodsheds of different types of agricultural land by calculating the land footprint of food consumption. On this basis, food self-sufficiency is defined as the ratio of available and required agricultural area for regional food demand. The results indicated that the self-sufficiency level provided by the arable land in the Pearl River Delta is low and cannot realize self-sufficiency at the regional and urban levels. The horticultural landscapes can provide self-sufficiency at the regional level, whereas the regions with water cannot, as their foodsheds extend over the boundary of the Pearl River Delta. For arable land, establishing a localized regional food system requires expanding the foodshed size. These findings provide evidence that megacity regions may face increasing difficulties in achieving self-sufficiency in the near future. This research can improve policymakers' understanding of the sustainability and resilience of regional food systems in megacity regions.

Predicting the photon energy of quasi-2D lead halide perovskites from the precursor composition through machine learning.

Quasi-2D perovskites with the general formula of L2A n-1Pb n X3n+1 (L = organic spacer cation, A = small organic cation or inorganic cation, X = halide ion, and n ≤ 5) are an emerging kind of luminescent material. Their emission color can be easily tuned by their composition and n value. Accurate prediction of the photon energy before experiments is essential but unpractical based on present studies. Herein, we use machine learning (ML) to explore the quantitative relationship between the photon energies of quasi-2D perovskite materials and their precursor compositions. The random forest (RF) model presents high accuracy in prediction with a root mean square error (RMSE) of ∼0.05 eV on a test set. By feature importance analysis, the composition of the A-site cation is found to be a critical factor affecting the photon energy. Moreover, it is also found that the phase impurity greatly lowers the photon energy and needs to be minimized. Furthermore, the RF model predicts the compositions of quasi-2D perovskites with high photon energies for blue emission. These results highlight the advantage of machine learning in predicting the properties of quasi-2D perovskites before experiments and also providing color tuning directions for experiments.

Key Factors Governing the External Quantum Efficiency of Thermally Activated Delayed Fluorescence Organic Light-Emitting Devices: Evidence from Machine Learning.

Thermally activated delayed fluorescence (TADF) materials enable organic light-emitting devices (OLEDs) to exhibit high external quantum efficiency (EQE), as they can fully utilize singlets and triplets. Despite the high theoretical limit in EQE of TADF OLEDs, the reported values of EQE in the literature vary a lot. Hence, it is critical to quantify the effects of the factors on device EQE based on data-driven approaches. Herein, we use machine learning (ML) algorithms to map the relationship between the material/device structural factors and the EQE. We established the dataset from a variety of experimental reports. Four algorithms are employed, among which the neural network performs best in predicting the EQE. The root-mean-square errors are 1.96 and 3.39% for the training and test sets. Based on the correlation and the feature importance studies, key factors governing the device EQE are screened out. These results provide essential guidance for material screening and experimental device optimization of TADF OLEDs.

AutoImplant 2020-First MICCAI Challenge on Automatic Cranial Implant Design.

The aim of this paper is to provide a comprehensive overview of the MICCAI 2020 AutoImplant Challenge. The approaches and publications submitted and accepted within the challenge will be summarized and reported, highlighting common algorithmic trends and algorithmic diversity. Furthermore, the evaluation results will be presented, compared and discussed in regard to the challenge aim: seeking for low cost, fast and fully automated solutions for cranial implant design. Based on feedback from collaborating neurosurgeons, this paper concludes by stating open issues and post-challenge requirements for intra-operative use. The codes can be found at https://github.com/Jianningli/tmi.

Computer-aided porous implant design for cranio-maxillofacial defect restoration.

The porous structure of the implant contributes significantly to prosthetic osseointegration in cranio-maxillofacial defect repair surgeries. This study establishes a system called EasyImplant that can easily and efficiently design customized cranio-maxillofacial implant with porous structure. Healthy side of the skull model is used to obtain the initial implant model on defective side by mirroring method. According to the curvature of undamaged surface, the initial model can be adjusted and repaired. Based on the initial implant model, porous implant structure can be generated efficiently using create sample points, distance Field and marching Cube algorithms. Finally, the connection plate is obtained through surface extruding and model merging. With EasyImplant, a complete porous implant model can be designed in a short time. The proposed methods can contribute to shorten the period of facial implant designing and reduce the incidence of surgical infection.

[Spatio-temporal Variations in Phytoplankton Community in Shahe Reservoir, Tianmuhu, China].

Monthly investigations of the phytoplankton community and the associated environmental drivers during the past eight years in the Shahe Reservoir, Jiangsu Province, China revealed the spatial and temporal variations of phytoplankton and the associated driving factors in the reservoir. The results show that the concentrations of total nitrogen (TN), total phosphorous (TP), turbidity (Turb), suspended solids (SS), and chlorophyll-a (CHL) were the highest in the upstream tributaries and the lowest in the downstream-linked reservoir. In contrast, the highest Secchi disk depth (SDD) was recorded in the Shahe Reservoir and that the lowest in the upstream tributaries. Significant differences in water quality indices were recorded among the upstream tributaries, the transition region, and the downstream-linked reservoir area (ANOVA, P<0.05). The biomass of phytoplankton was the highest in the upstream tributaries and the lowest in the reservoir. The highest biomass of phytoplankton was recorded in the summer and the lowest in the winter. Synedra, Cyclotella, Cryptomonas, and Achnanthes were the dominant genera in the spring; Synedra, Cryptomonas, Raphidiopsis, and Phormidium were dominant in the summer; Cryptomonas, Synedra, Raphidiopsis, and Aphanizomenon were dominant in the autumn; and Cryptomonas, Synedra, Achnanthes, and Cyclotella were dominant in the winter. Synedra and Cryptomonas were the dominant genera throughout the year. The correlation analysis shows that TP, water temperature, and SDD were the most important driving factors for the spatial and temporal variations of phytoplankton. Notable spatial differences were recorded for Cryptomonas, while minimal variations were recorded for the remaining species. A smaller number sampling sites and a higher sampling frequency are needed to characterize the phytoplankton community in the Shahe Reservoir.

catena-Poly[[diaqua-copper(II)]-µ-hy-drox-ido-κO:O-µ-[4-(4H-1,2,4-triazol-4-yl)benzoato]-κN:N].

The title compound, [Cu(C(9)H(6)N(3)O(2))(OH)(H(2)O)(2)](n), adopts a chain motif along [010] in which the Cu(II) atoms are bridged by hy-droxy groups and 4-(1,2,4-triazol-4-yl)benzoate (tab) ligands. The Cu(II) atom lies on an inversion center and is six-coordinated by two N atoms from two tab ligands, two hy-droxy groups and two water mol-ecules, giving a distorted octa-hedral geometry. The hy-droxy group and the tab ligand are located on a mirror plane. One of the water H atoms is disordered over two positions with equal occupancy factors. Inter-molecular O-H⋯O hydrogen bonds extend the chains into a layer parallel to (100) and C-H⋯O hydrogen bonds connect the layers into a three-dimensional network.

Poly[(µ(3)-camphorato-κO:O':O'')(2-methyl-1H-imidazole-κN)zinc(II)].

In the title compound, [Zn(C(10)H(14)O(4))(C(4)H(6)N(2))](n), each Zn(II) ion is coordinated by one N atom from one 2-methyl-1H-imidazole ligand and three O atoms from two camphorate (cap) ligands in a distorted tetra-hedral geometry. In one of the cap ligands, one methyl group is disordered between positions 1 and 3 in a 0.518 (12):0.482 (12) ratio. Each cap ligand bridges three Zn(II) ions, forming two-dimensional layers, which inter-act further via N-H⋯O hydrogen bonds.

catena-Poly[[[bis-(thio-cyanato-κN)zinc(II)]-µ-1,2-bis-{[2-(2-pyrid-yl)-1H-imidazol-1-yl]meth-yl}benzene] 0.28-hydrate].

The title one-dimensional coordination polymer, {[Zn(NCS)(2)(C(24)H(20)N(6))(2)]·0.28H(2)O}(n), was obtained by the reaction of Zn(OAc)(2)·2H(2)O, KSCN and 1,2-bis-{[2-(2-pyrid-yl)-1H-imid-azol-1-yl]meth-yl}benzene (hereafter L). The Zn(II) ion shows a distorted octa-hedral coordination geometry and is coordin-ated by two N atoms from two SCN(-) anions and four N atoms from two organic ligands. The L ligands act as bridging bis-chelating ligands with cis coordination modes at the Zn(II) ion. One-dimensional coordination polymers are arranged into layers by π-π stacking inter-actions between the imidazole rings of adjacent chains, with an inter-planar distance of 3.46 (1) Šand centroid-centroid distances of 3.8775 (16) Å. One of the thio-cyanate ligands is disordered over two positions with an occupancy factor of 0.564 (3) for the major component. The partially occupied water mol-ecule forms an O-H⋯S hydrogen bond with the disordered thio-cyanate group.