Investigating quantitative approach for microalgal biomass using deep convolutional neural networks and image recognition.

The effective monitoring of microalgae cultivation is crucial for optimizing their energy utilization efficiency. In this paper, a quantitative analysis method, using microalgae images based on two convolutional neural networks, EfficientNet (EFF) and residual network (RES), is proposed. Suspension samples prepared from two types of dried microalgae powders, Rhodophyta (RH) and Spirulina (SP), were used to mimic real microalgae cultivation settings. The method's prediction accuracy of the algae concentration ranges from 0.94 to 0.99. RH, with a distinctively pronounced red-green-blue value shift, achieves a higher prediction accuracy than SP. The prediction results of the two algorithms were significantly superior to those of a linear regression. Additionally, RES outperforms EFF in terms of its generalization ability and robustness, which is attributable to its distinct residual block architecture. The RES provides a viable approach for the image-based quantitative analysis.

The Impact of Agroecosystems on Nitrous Acid (HONO) Emissions during Spring and Autumn in the North China Plain.

Solar radiation triggers atmospheric nitrous acid (HONO) photolysis, producing OH radicals, thereby accelerating photochemical reactions, leading to severe secondary pollution formation. Missing daytime sources were detected in the extensive HONO budget studies carried out in the past. In the rural North China Plain, some studies attributed those to soil emissions and more recent studies to dew evaporation. To investigate the contributions of these two processes to HONO temporal variations and unknown production rates in rural areas, HONO and related field observations obtained at the Gucheng Agricultural and Ecological Meteorological Station during spring and autumn were thoroughly analyzed. Morning peaks in HONO frequently occurred simultaneously with those of ammonia (NH3) and water vapor both during spring and autumn, which were mostly caused by dew and guttation water evaporation. In spring, the unknown HONO production rate revealed pronounced afternoon peaks exceeding those in the morning. In autumn, however, the afternoon peak was barely detectable compared to the morning peak. The unknown afternoon HONO production rates were attributed to soil emissions due to their good relationship to soil temperatures, while NH3 soil emissions were not as distinctive as dew emissions. Overall, the relative daytime contribution of dew emissions was higher during autumn, while soil emissions dominated during spring. Nevertheless, dew emission remained the most dominant contributor to morning time HONO emissions in both seasons, thus being responsible for the initiation of daytime OH radical formation and activation of photochemical reactions, while soil emissions further maintained HONO and associated OH radial formation rates at a high level, especially during spring. Future studies need to thoroughly investigate the influencing factors of dew and soil emissions and establish their relationship to HONO emission rates, form reasonable parameterizations for regional and global models, and improve current underestimations in modeled atmospheric oxidation capacity.

Correlating Young's Modulus with High Thermal Conductivity in Organic Conjugated Small Molecules.

Attaining elevated thermal conductivity in organic materials stands as a coveted objective, particularly within electronic packaging, thermal interface materials, and organic matrix heat exchangers. These applications have reignited interest in researching thermally conductive organic materials. The understanding of thermal transport mechanisms in these organic materials is currently constrained. This study concentrates on N, N'-dioctyl-3,4,9,10-perylenedicarboximide (PTCDI-C8), an organic conjugated crystal. A correlation between elevated thermal conductivity and augmented Young's modulus is substantiated through meticulous experimentation. Achievement via employing the physical vapor transport method, capitalizing on the robust C═C covalent linkages running through the organic matrix chain, bolstered by π-π stacking and noncovalent affiliations that intertwine the chains. The coexistence of these dynamic interactions, alongside the perpendicular alignment of PTCDI-C8 molecules, is confirmed through structural analysis. PTCDI-C8 thin film exhibits an out-of-plane thermal conductivity of 3.1 ± 0.1 W m-1 K-1, as determined by time-domain thermoreflectance. This outpaces conventional organic materials by an order of magnitude. Nanoindentation tests and molecular dynamics simulations elucidate how molecular orientation and intermolecular forces within PTCDI-C8 molecules drive the film's high Young's modulus, contributing to its elevated thermal conductivity. This study's progress offers theoretical guidance for designing high thermal conductivity organic materials, expanding their applications and performance potential.

Application of the BOPPPS-CBL model in electrocardiogram teaching for nursing students: a randomized comparison.

BACKGROUND/AIM: Interpreting an electrocardiogram (ECG) is a vital skill for nurses in cardiology. This study aimed to evaluate the efficacy of the bridge-in, objective, preassessment, participatory learning, post-assessment, and summary (BOPPPS) model, when combined with case-based learning (CBL), in enhancing nursing students' ECG interpretation capabilities. MATERIALS & METHODS: Nursing students were randomly divided into two groups: one utilizing the BOPPPS model combined with CBL (BOPPPS-CBL), and the other employing a traditional lecture-based learning (LBL) model. All participants underwent training and completed pre- and post-course quizzes. RESULTS: The BOPPPS-CBL model significantly improved nursing students' abilities in ECG interpretation compared to the traditional LBL model group. The BOPPPS-CBL model proved to be a comprehensive and effective method for enhancing students' attitudes towards teaching and learning. DISCUSSION: Our study demonstrated for the first time that the BOPPPS-CBL model is an innovative and effective method for promoting nurses' accuracy in ECG interpretation. It highlights the potential of this approach as a superior alternative to traditional learning methods.

Organic Conjugated Small Molecules with High Thermal Conductivity as an Effective Coupling Layer for Heat Transfer.

As the features of electronics are miniaturized, the need for interfacial thermal coupling layers to enhance their thermal transfer efficiency and improve device performance becomes critical. Organic conjugated small molecules possess a unique combination of periodic crystal structures and conjugated units with π electrons, resulting in notable thermal conductivities and molecular structure orientation that facilitates directed heat transfer. Nevertheless, there is a noticeable gap in literatures regarding the thermal properties of organic conjugated small molecules and their potential applications in nanoscale thermal management. Herein, we report the fabrication of high-quality thin films of organic conjugated small molecules. The result reveals that the 2D organic conjugated small molecule thin films exhibit a high cross-plane thermal conductivity of 3.2 W/m K. The increased thermal conductivity is attributed to the well-organized lattice structure and existence of π-electrons induced by conjugated systems. The studied conjugated small molecules engage in π-π stacking interactions with carbon materials and efficiently exchange energy with electrons in metals, promoting rapid interfacial heat transfer. These molecules act as coupling layers, significantly enhancing thermal transfer efficiency between graphite-based thermal pads and copper heat sinks. This pioneering research represents the inaugural investigation of the thermal performance of conjugated organic small molecules. These findings highlight the potential of conjugated small molecules as thermal coupling layers, offering tunable combinations of desirable properties.

Creating Biomimetic Central-Radial Skeletons with Efficient Mass Adsorption and Transport.

Porous skeletons play a crucial role in various applications. Their fundamental significance stems from their remarkable surface area and capacity to enhance mass adsorption and transport. Freeze-casting is a commonly utilized methodology for the production of porous skeletons featuring vertically aligned channels. Nevertheless, the resultant single-oriented skeleton displays anisotropic mass transfer characteristics and suboptimal mechanical properties. Our investigation was motivated by the intricate microstructures observed in botanical organisms, leading us to devise an advanced freeze-casting methodology. A novel central-radial skeleton with significantly enhanced capabilities has been successfully engineered. The central-radial architecture demonstrates superior refinement and uniformity in its pore structure, featuring an axial mass transfer axis and meticulously arranged radial channels. This microstructure endows the porous skeleton with a higher compression resilience, superior adsorption rate, and structural maintenance capacity. Through a rigorous examination of the thermal conductivity of skeleton-filled composites coupled with comprehensive COMSOL simulations, the exceptional characteristics of this unique structural arrangement have been definitively ascertained. Furthermore, the efficacy of implementing this skeleton in chip cooling and photothermal conversion has been convincingly substantiated. Our pioneering method of microstructure preparation, employing freeze-casting, holds immense potential in expanding its applicability and inspiring innovative concepts for the advancement of novel structures.

Effects of solvent phase recycling on microalgae liquefaction in ethanol: Bio-oil production and nitrogen transformation.

Liquefaction of microalgae in ethanol offers an eco-friendly bio-oil alternative, but solvent recycling is crucial for sustainability due to extra costs. In this work, Chlorella vulgaris was liquefied in supercritical ethanol at 260 °C, and the solvent phase (SP) separated from bio-oil was recovered and reused. Five liquefaction cycles were performed at identical temperature and pressure conditions to investigate the effects on oil production and nitrogen transformation. The findings demonstrated a gradual increase in water content in recycled SP. Ethanol-water co-solvent as the reaction medium promoted the decomposition and re-polymerization of protein in raw material, thus increasing the bio-oil yield (76.84 %) and higher heating value (33.53 MJ/kg) to some extent. Simultaneously, the relative nitrogen content of bio-oil rose from 8.03 % to 8.52 %, predominantly in the form of nitrogen heterocycles. The potential pathway for nitrogen conversion was revealed, which establishes a theoretical basis for the subsequent denitrification of bio-oil.

Sedimentary Organic Facies Division and Hydrocarbon-Generation Potential of Source Rocks in Coal-Bearing Strata-A Case Study of the Upper Paleozoic in Huanghua Depression, Bohai Basin, China.

Sedimentary organic facies cover the formation, evolution, and spatial distribution characteristics of organic matter, and they are effective tools for oil and gas resource evaluation and basin prospect prediction. According to the basic organic rock composition of the sedimentary organic facies, combined with the sedimentary facies and organic matter geochemical characteristics of Carboniferous-Permian strata, the characteristics of organic facies and hydrocarbon-generation potential of Upper Paleozoic source rocks in Huanghua Depression are being discussed. The results show that source rocks of Taiyuan and Shanxi Formations in the study area were oil-prone, and the oil-generation potential of mudstone is greater than that of carbonaceous mudstone and coal. The organic facies in the study area can be divided into six types: (1) terrestrial forest organic facies; (2) shallow swamp forest organic facies; (3) deep swamp forest organic facies; (4) deep swamp reed organic facies; (5) flowing water swamp organic facies; and (6) open water organic facies. The Taiyuan Formation is mainly composed of flowing water swamp, deep swamp forest, and shallow swamp forest with a strong hydrocarbon-generation capacity, while the Shanxi Formation chiefly includes organic facies of the deep swamp forest and shallow swamp forest. The deep swamp reed sedimentary organic facies had the highest hydrocarbon-generation potential, while the terrestrial forest sedimentary organic facies had the worst hydrocarbon-generation potential. Coal had a certain oil-generating capacity but was weaker than that of mudstone. Compared with mudstone, coal had a stronger gas-generating capacity.

Structure and Sequence Aligned Code Summarization with Prefix and Suffix Balanced Strategy.

Source code summarization focuses on generating qualified natural language descriptions of a code snippet (e.g., functionality, usage and version). In an actual development environment, descriptions of the code are missing or not consistent with the code due to human factors, which makes it difficult for developers to comprehend and conduct subsequent maintenance. Some existing methods generate summaries from the sequence information of code without considering the structural information. Recently, researchers have adopted the Graph Neural Networks (GNNs) to capture the structural information with modified Abstract Syntax Trees (ASTs) to comprehensively represent a source code, but the alignment method of the two information encoder is hard to decide. In this paper, we propose a source code summarization model named SSCS, a unified transformer-based encoder-decoder architecture, for capturing structural and sequence information. SSCS is designed upon a structure-induced transformer with three main novel improvements. SSCS captures the structural information in a multi-scale aspect with an adapted fusion strategy and adopts a hierarchical encoding strategy to capture the textual information from the perspective of the document. Moreover, SSCS utilizes a bidirectional decoder which generates a summary from opposite direction to balance the generation performance between prefix and suffix. We conduct experiments on two public Java and Python datasets to evaluate our method and the result show that SSCS outperforms the state-of-art code summarization methods.

Effect of Petroleum Generation and Retention on Nanopore Structure Change in Laminated and Massive Shales-Insights from Hydrous Pyrolysis of Lacustrine Source Rocks from the Permian Lucaogou Formation.

The lacustrine shale of the Middle Permian Lucaogou Formation in the Jimusar Sag is the principal prospective unconventional target in the Junggar Basin. The effect of petroleum generation and retention on nanopore structure change during thermal maturity in lacustrine shale is still unclear. In this study, two laminated and two massive shale samples from the Permian Lucaogou Formation were selected to study this change by closed hydrous pyrolysis. The pyrolysis temperatures were 295, 320, 345, 370, and 400 °C, which cover from the mature to the post-mature stage. Total organic carbon (TOC), Rock-Eval, and low-pressure N2 adsorption tests on pyrolyzed shale samples before and after extractable organic matter (EOM) extraction were conducted systematically. The results indicate that (1) the petroleum generation on nanopore structure change is in stages. The peak nanopore volume expanding stage is the late oil window (R o = 0.9-1.35%). At the post-mature stage (R o > 1.35%), the mesopore volume decreased and the majority of the nanopore space is from macropores. (2) The presence of EOM decreased both mesopores and macropores in the peak oil window. (3) The organic-rich laminated shale generated more macropores than massive shale with increasing thermal maturity. The results of this study shed light on the dynamic effect of laminae fabric, petroleum generation, and retention on shale nanopore structure change across the oil window.

CRISP method with flipped classroom approach in ECG teaching of arrhythmia for trainee nurses: a randomized controlled study.

BACKGROUND: This study aimed to explored the effects of the Cardiac Rhythm Identification for Simple People (CRISP) method with flipped classroom approach for arrhythmia interpretation in electrocardiogram (ECG) by trainee nurses. METHODS: A total of 120 trainee nurses were enrolled and randomly divided into the experimental group and the control group using lecture-based learning method. We observed the effects of the two methods in ECG interpretation training and investigated the students' attitudes toward the teaching practices. RESULTS: After training, the ECG test scores in the experimental group were significantly higher than that of the control group. Six months later, the ECG test scores of the experimental group was still higher. Self-learning enthusiasm, understanding of teaching content, satisfaction of teaching mode, satisfaction of teaching effectiveness, and interest in learning ECG were significantly higher in the experimental group. CONCLUSION: CRISP method with flipped classroom approach is a new and effective mode worth trying in ECG teaching for trainee nurses.

Outcomes after transfer from hemodialysis to peritoneal dialysis vs peritoneal dialysis as initial therapy: A systematic review and meta-analysis.

Outcomes of patients who are transferred to peritoneal dialysis (PD) after an initial phase of hemodialysis (HD) compared to patients initiating dialysis with PD is controversial. We performed a systematic literature to assess evidence. Primary outcome was overall survival (OS), while secondary outcomes were technique failure, mortality and peritonitis. Meta-analysis indicated that PD initial group had significantly better OS as compared to HD to PD group. Pooled analysis demonstrated a significantly higher probability of technique failure in the HD to PD group as compared to PD initial group. Mortality rate in HD to PD group was significantly higher but there was no statistically significant difference in peritonitis rates between the two groups. On meta-regression analysis, transfer from HD to PD due to vascular access problems was associated with significantly reduced probability of OS. Our study indicates that patients transferred from HD to PD after at least 3 months of HD therapy may have reduced OS as compared to patients initiating dialysis with PD. Our findings lend some support to PD first policy and the need for heightened vigilance among the switched patients to monitor for adverse events.

Micrometer Copper-Zinc Alloy Particles-Reinforced Wood Plastic Composites with High Gloss and Antibacterial Properties for 3D Printing.

In this work, micrometer copper-zinc alloy particles-reinforced particleboard wood flour/poly (lactic acid) (mCu-Zn/PWF/PLA) wood plastic composites with high gloss and antibacterial properties for 3D printing were prepared by a melt blending process. The structure and properties of the composites with different contents of mCu-Zn were analyzed by means of mechanical testing, dynamic mechanical analysis, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and antibacterial testing. The results showed that the mechanical properties, thermal stability, and antibacterial performance of the composites were significantly improved, as mCu-Zn was added into the wood plastic composites. When adding 2 wt.% mCu-Zn, the flexural strength of mCu-Zn/PWF/PLA composites (with 5 wt.% of particleboard wood flour) (PWF) increased by 47.1% compared with pure poly (lactic acid) (PLA), and 18.9% compared with PWF/PLA wood plastic composites. The surface gloss was increased by 1142.6% compared with PWF/PLA wood plastic composites. Furthermore, the inhibition rates of mCu-Zn/PWF/PLA composites against Escherichia coli reached 90.43%. Therefore, this novel high gloss and antibacterial wood plastic composites for fused deposition modeling (FDM) 3D printing have potential applications in personalized and classic furniture, art, toys, etc.

Effect of Interleukin-27 Genetic Variants on Atrial Fibrillation Susceptibility.

AIM: Atrial fibrillation (AF) is the most common cardiac arrhythmia. No data are available on the association between the polymorphisms of interleukin-27 (IL-27) and AF in the Chinese Han population. This study was performed to determine if polymorphisms within the IL-27 gene are involved in the AF susceptibility. METHODS: Two hundred seventy AF patients and 303 healthy individuals were examined for two IL-27 gene polymorphisms (rs153109 and rs17855750) by polymerase chain reaction-restriction fragment length polymorphism methodology. RESULTS: An association between the IL-27 single nucleotide polymorphism (SNP) rs153109 and AF was found in Chinese Han population. The G allele and GG genotype of rs153109 were associated with increased AF risk (odds ratio [OR]: 1.35, 95% confidence intervals [CI] = 1.06-1.71, p = 0.02 and OR: 1.66, 95% CI = 1.03-2.65, p = 0.03 in the recessive genetic model, respectively). The significance of the association between the GG genotype and AF risk did not survive a Bonferroni's correction. Similarly, no significant differences in the allele and genotype frequencies of the rs17855750 SNP was observed between the AF patients and controls. CONCLUSIONS: Our findings indicated that the IL-27 genetic polymorphisms may be associated with susceptibility of AF in Chinese Han population.

IL-27 genetic variation and susceptibility of dilated cardiomyopathy in Chinese Han population.

AIM: Accumulating data showed that IL-27 polymorphisms are linked to the susceptibility of some autoimmune diseases. We assessed whether there was an association between two single nucleotide polymorphisms (SNPs) of IL-27 gene and dilated cardiomyopathy (DCM). MATERIALS & METHODS: Two SNPs (rs153109 and rs17855750) of IL-27 gene were genotyped by PCR-restriction fragment length polymorphism in 261 DCM patients and 303 unrelated healthy subjects in Chinese Han population. RESULTS: Compared with controls, our results showed that SNP rs153109 displayed significant associations with DCM in Chinese Han population, whereas no differences in genotype or allele frequencies were found between DCM patients and controls at SNP rs17855750. CONCLUSION: Our study showed that, for the first time, the association of the IL-27 gene SNP with the patients with DCM.

[Study on crystal chemistry and spectra of feldspar from Zhoukoudian granodiorite].

The chemical composition and spectra characteristic of feldspar from Zhoukoudian granodiorite were systematically analyzed. Based on the field work, some feldspar samples were selected for crystal chemistry and structure analysis through EMPA, IR, LRM and XRD. The compositions of the feldspar range between Ab (85.21) Or (0.18) An (9.11) and Ab (90.06) Or (3.00) An (13.27) by electronic microscope probe analysis. According to the XRD peak and its diffraction intensity, the mineral species was found the unit cell parameters were calculated. The absorption bands and peaks of infrared and Raman spectra were also assigned and the results show that the characteristics of its infrared and Raman spectra are in accordance with the ideal atlas of albite. The infrared spectra show that all the analyzed feldspar grains contain structural hydrogen, which occur as OH-. On the basis of the above analyses, the crystal chemistry and structure characteristics of feldspar were summarized.

Effects of temperature and surfactants on naphthalene and phenanthrene sorption by soil.

Adsorption experiments were carried out to investigate the sorption behaviors of naphthalene and phenanthrene in six different soils and to determine the effects of temperature, linear alkylbenzene sulfonate (LAS) and cetylrimethyl ammonium bromide (CTAB) on sorption. The results show that for a given sorbent phenanthrene exhibited greater nonlinear and stronger sorption than naphthalene. There was a strong negative correlation for the K(OC) values with organic carbon content (f(OC)). The increase of temperature was not favorable to sorption. Sorption decreased along with the increasing aqueous LAS concentration from 0 to 1000 mg/L. At low CTAB concentration (< 100 mg/L), the adsorption increased as CTAB hemimicelles formed on the soil surface. At high concentration, CTAB decreased the adsorption by occupying active hydrophobic adsorption sites and solubilization of naphthalene and phenanthrene.

[Adsorption of toluene and naphthalene on Beijing soils and its influence factor].

Static adsorption experiments were carried out to investigate the adsorption of toluene and naphthalene on Beijing soils, and to determine the influence of temperature and surfactants on adsorption. Although the affinity of petroleum hydrocarbons for seven soils is different, the adsorption isotherms of toluene and naphthalene on seven soils are well described by the Freundlich type. The adsorbed amount of naphthalene is higher than that of toluene on the same soil. High temperature doesn't benefit adsorption. Cetylrimethyl ammonium bromide (CTAB) and sodium dodecyl benzene sulfonate (SDBS) both have a positive effect on desorption of toluene and naphtalaene from soil. The desorption rate of toluene and naphthalene in the presence of CTAB and SDBS is 27.5%, 12.1% and 64.3%, 48.8%, respectively, which show that SDBS plays a much more important role in desorption than CTAB. The adsorbed quantities of toluene and naphthalene decrease with increasing SDBS concentration. When CTAB concentration is lower than the critical micelle concentration (CMC), adsorption increases with increasing CTAB concentration; When CTAB concentration is equal to or higher than CMC, adsorption decreases with increasing CTAB concentration.