The endoplasmic reticulum adopts two distinct tubule forms.

The endoplasmic reticulum (ER) is a versatile organelle with diverse functions. Through superresolution microscopy, we show that the peripheral ER in the mammalian cell adopts two distinct forms of tubules. Whereas an ultrathin form, R1, is consistently covered by ER-membrane curvature-promoting proteins, for example, Rtn4 in the native cell, in the second form, R2, Rtn4 and analogs are arranged into two parallel lines at a conserved separation of ∼105 nm over long ranges. The two tubule forms together account for ∼90% of the total tubule length in the cell, with either one being dominant in different cell types. The R1­R2 dichotomy and the final tubule geometry are both coregulated by Rtn4 (and analogs) and the ER sheet­maintaining protein Climp63, which, respectively, define the edge curvature and lumen height of the R2 tubules to generate a ribbon-like structure of well-defined width. Accordingly, the R2 tubule width correlates positively with the Climp63 intraluminal size. The R1 and R2 tubules undergo active remodeling at the second/subsecond timescales as they differently accommodate proteins, with the former effectively excluding ER-luminal proteins and ER-membrane proteins with large intraluminal domains. We thus uncover a dynamic structural dichotomy for ER tubules with intriguing functional implications.

Biomineralization-Inspired Copper Sulfide Decorated Aramid Textiles via In Situ Anchoring toward Versatile Wearable Thermal Management.

Designing smart textiles for personal thermal management (PTM) is an effective strategy for thermoregulation and energy saving. However, the manufacture of versatile high-performance thermal management textiles for complex real-world environments remains a challenge due to the limitations of functional integration, material properties, and preparation procedures. In this study, an aramid fabric based on in situ anchored copper sulfide nanostructure is developed. The textile with excellent solar and Joule heating properties can effectively keep the body warm even at low energy inputs. Meanwhile, the reduced infrared emissivity of the textile decreases the thermal radiation losses and helps to maintain a constant body temperature. Impressively, the textile integrates superb electromagnetic shielding, near-complete UV protection properties, and ideal resistance to fire and bacteria. This work provides a simple strategy for fabricating multi-functional integrated wearable devices with flexibility and breathability, which is highly promising in versatile PTM applications.

Unilateral biportal endoscopic discectomy versus microdiscectomy for lumbar disc herniation: a systematic review and meta-analysis.

PURPOSE: This study aimed to compare unilateral biportal endoscopic discectomy (UBED) with microdiscectomy (MD) for treating lumbar disk herniation (LDH). METHODS: A comprehensive literature search was conducted in the Embase, PubMed, Cochrane Library, CNKI, and Web of Science databases from database inception to April 2023 to identify studies comparing UBED and MD for treating LDH. This study evaluated the visual analog scale (VAS) score, Oswestry disability index (ODI), Macnab scores, operation time, estimated blood loss, hospital stay, and complications, estimated blood loss, visual analog scale (VAS) score, Oswestry disability index (ODI), and Macnab scores at various pre- and post-surgery stages. The meta-analysis was performed using RevMan 5.4 software. RESULTS: The meta-analysis included 9 distinct studies with a total of 1001 patients. The VAS scores for low back pain showed no significant differences between the groups at postoperative 1-3 months (P = 0.09) and final follow-up (P = 0.13); however, the UBED group had lower VAS scores at postoperative 1-3 days (P = 0.02). There were no significant differences in leg pain VAS scores at baseline (P = 0.05), postoperative 1-3 days (P = 0.24), postoperative 1-3 months (P = 0.78), or at the final follow-up (P = 0.43). ODI comparisons revealed no significant differences preoperatively (P = 0.83), at postoperative 1 week (P = 0.47), or postoperative 1-3 months (P = 0.13), and the UBED group demonstrated better ODI at the final follow-up (P = 0.03). The UBED group also exhibited a shorter mean operative time (P = 0.03), significantly shorter hospital stay (P < 0.00001), and less estimated blood loss (P = 0.0002). Complications and modified MacNab scores showed no significant differences between the groups (P = 0.56 and P = 0.05, respectively). CONCLUSION: The evidence revealed no significant differences in efficacy between UBED and MD for LDH treatment. However, UBED may offer potential benefits such as shorter hospital stays, lower estimated blood loss, and comparable complication rates.

Comprehensive assembly and comparative examination of the full mitochondrial genome in Castanea mollissima Blume.

The Chinese chestnut, Castanea mollissima Blume, a nut-bearing tree native to China and North Korea, belongs to the Fagaceae family. As an important genetic resource, C. mollissima is vital in enhancing edible chestnut varieties and offers significant insights into the origin and evolution of chestnut species. While the chloroplast genome of C. mollissima has been sequenced, its mitochondrial genome (mitogenome) remains largely uncharted. In this study, we have characterized the C. mollissima mitogenome, assembling it utilizing reads from both BGI and Nanopore sequencing platforms, and conducted a comparative analysis with the mitochondrial genomes of closely related species. The mitogenome of C. mollissima manifests a polycyclic structure consisting of two circular molecules measuring 363,232 bp and 24,806 bp, respectively. This genome encompasses 35 unique protein-coding genes, 19 tRNA genes, and three rRNA genes. A total of 139 SSRs were identified throughout the entire C. mollissima mitogenome. Furthermore, the combined length of homologous fragments between the chloroplast and mitochondrial genomes was 5766 bp, constituting 1.49% of the mitogenome. We also predicted 484 RNA editing sites in C. mollissima, demonstrating C-to-U RNA editing. Phylogenetic analysis of related species' mitogenomes showed that C. mollissima was closely related to Lithocarpus litseifolius (Hance) Chun and Quercus acutissima Carruth. Interestingly, the mitogenome sequences of C. mollissima, L. litseifolius, Q. acutissima, Fagus sylvatica L., and Juglans mandshurica Maxim did not show conservation in their alignments, indicating frequent genome reorganization. This report marks the inaugural study of the C. mollissima mitogenome, serving as a benchmark genome for economically significant plants within the Castanea genus. Moreover, it supplies invaluable information that can guide future molecular breeding efforts and contribute to the broader understanding of chestnut genomics.

Optimizing irrigation strategies for sustainable crop productivity and reduced groundwater consumption in a winter wheat-maize rotation system.

Inefficient irrigation practices have hindered crop yields, wasted irrigation water resources, and posed threats to groundwater levels and agricultural sustainability. This study evaluated different irrigation strategies for a winter wheat-summer maize rotation system to identify sustainable practices for maintaining yields while reducing groundwater depletion. A two-year field experiment was conducted, implementing three optimized irrigation strategies during the winter wheat season: I-4 (irrigated until the soil water content (SWC) of the 40 cm soil layer reaches 60% of field capacity (FC), I-6 (irrigated until the SWC of the 60 cm soil layer reaches 80% FC), and a rainfed (R) as control. Irrigation was repeated when the SWC dropped to the specified level. No irrigation level was used during the summer maize season, except for irrigation after sowing that ensuring the normal emergence of maize. WHCNS (Water Heat Carbon Nitrogen Simulator) model was developed to simulate soil water dynamics, field water consumption, and yield of both crops. The result indicated WHCNS model accurately simulated water dynamics, consumption, and grain yield. Compared to R treatment, the I-4 treatment significantly increased annual crop yield by 19.83%-28.65% (p < 0.05), while maintaining similar crop water productivity. Furthermore, the I-4 treatment achieved comparable yields to the I-6 treatment, but with a 33.91% reduction in irrigation water use, resulting in a 33.46% increase in crop water productivity and a 90.53% increase in irrigation water productivity. From a sustainable perspective, the I-4 treatment effectively reduced field water losses and maintained relatively high soil water storage, particularly in the topsoil, which was beneficial for the early growth of subsequent crops. The R treatment greatly contributed to groundwater recharge when precipitation was sufficient, while it led to severe yield losses. Overall, under the condition of annual rotation planting systems, the I-4 treatment sustainably maintained yields with less irrigation, decreasing groundwater consumption. This approach could conserve regional water resources and groundwater table while upholding agricultural productivity and achieving system sustainable water use.

Transcriptome sequencing and differential expression analysis of seed starch accumulation in Chinese chestnut Metaxenia.

BACKGROUND: Chestnut seeds are important kinds of edible nuts rich in starch and protein. The characteristics and nutrient contents of chestnut have been found to show obvious metaxenia effects in previous studies. To improve the understanding of the effect of metaxenia on chestnut starch and sucrose metabolism, this study used three varieties of chestnut, 'Yongfeng 1', 'YongRen Zao' and 'Yimen 1', as male parents to pollinate the female parent, 'Yongfeng 1', and investigated the mechanisms of starch and sucrose metabolism in three starch accumulation stages (70 (S1), 82 (S2), and 94 (S3) days after pollination, DAP) in chestnut seed kernels. RESULT: Most carbohydrate metabolism genes were highly expressed in YFF (self-pollinated 'Yongfeng 1') in stage S2 and in YFR ('Yongfeng 1' × 'Yongren Zao') and YFM ('Yongfeng 1' × 'Yimen 1') in stage S3. In stage S3, hub genes encoding HSF_DNA-binding, ACT, Pkinase, and LIM proteins and four transcription factors were highly expressed, with YFF showing the highest expression, followed by YFR and YFM. In addition, transcriptome analysis of the kernels at 70, 82 and 94 DAP showed that the starch granule-bound starch synthase (EC 2.4.1.242) and ADP-glucose pyrophosphorylase (EC 2.7 .7.27) genes were actively expressed at 94 DAF. Chestnut seeds regulate the accumulation of soluble sugars, reducing sugars and starch by controlling glycosyl transferase and hydrolysis activity during development. CONCLUSION: These results and resources have important guiding significance for further research on starch and sucrose metabolism and other types of metabolism related to chestnut metaxenia.

Effect of equipment layout on bioaerosol temporal-spatial distribution and deposition in one BSL-3 laboratory.

Reasonable equipment layout is essential for creating a healthy and safe environment, especially in a three-level biosafety laboratory with high potential risk factors of infection. Since 2019, COVID-19, an emerging infection has swept the world and caused severe losses. Biosafety laboratories are mandatory sites for detecting high-risk viruses, so related research is urgently needed to prevent further laboratory-acquired infections of operators. This study investigated the effects of obstacles on exposure infection of staff in a biosafety laboratory with related experimental equipment. The numerical simulation results are highly verified by the measured results. The results indicate that although the equipment layout does not affect the bioaerosol removal time, nearly 17% of the pollutant particles in the actual laboratory cannot be discharged effectively compared with the ideal situation. These particles lingered in the lower space under the influence of vortex, which would increase the respiratory risk of operators. In addition, after the experiment a large part of bioaerosol particles would be captured by equipment and floor, and the deposition rate per unit area is 0.45%/m2 and 0.8%/m2, respectively. Although the results show that the equipment layout could reduce the pollution on the floor, the disinfection is still an important link, especially on the surfaces of equipment. Meanwhile, the result also indicates that the action should be light and slow when operating in BSL-3 laboratory, so as to avoid the secondary suspension pollution of bioaerosol particles on the equipment surface and floor.

[A new guaiane-type sesquiterpenoid from Croton yunnanensis].

Five sesquiterpenoids were isolated from 90% ethanol extract of Croton yunnanensis by silica gel,Sephadex LH-20 column chromatography,as well as prep-HPLC methods. Based on MS,1 D and 2 D NMR spectral analyses,the structures of the five compounds were identified as 11-methoxyl alismol(1),6ß,7ß-epoxy-4α-hydroxyguaian-10-ene(orientalol C,2),multisalactone D(3),arvestonol(4),and 4,5-dihydroblumenol A(5). Compound 1 was a new guaiane-type sesquiterpenoid. Compounds 2-4 were isolated from the Croton genus for the first time,and compound 5 was obtained from this plant for the first time.

Recent progress and performance evaluation for polyaniline/graphene nanocomposites as supercapacitor electrodes.

Polyaniline (PANi)/graphene nanocomposites have attracted tremendous interest because of their great potential in electrochemical energy storage applications, especially supercapacitors. We herein focus on the composite synthesis, device fabrication and particularly various techniques for the improvement of electrochemical performance. It is imperative to take close control of the interface in these nanostructured composites, which thus would lead to the desired synergistic effects and cyclic stability with the efficient diffusion of electrolyte ions and electrons. Challenges and perspectives are discussed for the development of highly efficient PANi/graphene electrodes for supercapacitors.

PEDOT-based composites as electrode materials for supercapacitors.

Poly (3, 4-ethylenedioxythiophene) (denoted PEDOT) already has a brief history of being used as an active material in supercapacitors. It has many advantages such as low-cost, flexibility, and good electrical conductivity and pseudocapacitance. However, the major drawback is low stability, which means an obvious capacitance drop after a certain number of charge-discharge cycles. Another disadvantage is its limited capacitance and this becomes an issue for industrial applications. To solve these problems, there are several approaches including the addition of conducting nanofillers to increase conductivity, and mixing or depositing metal oxide to enhance capacitance. Furthermore, expanding the surface area of PEDOT is one of the main methods to improve its performance in energy storage applications through special processes; for example using a three-dimensional substrate or preparing PEDOT aerogel through freeze drying. This paper reviews recent techniques and outcomes of PEDOT based composites for supercapacitors, as well as detailed calculations about capacitances. Finally, this paper outlines the new direction and recent challenges of PEDOT based composites for supercapacitor applications.

Accuracy and postoperative assessment of robot-assisted placement of pedicle screws during scoliosis surgery compared with conventional freehand technique: a systematic review and meta-analysis.

STUDY DESIGN: A systematic review and meta-analysis. BACKGROUND: The complexity of human anatomical structures and the variability of vertebral body structures in patients with scoliosis pose challenges in pedicle screw placement during spinal deformity correction surgery. Through technological advancements, robots have been introduced in spinal surgery to assist with pedicle screw placement. METHODS: A systematic search was conducted using PubMed, Cochrane, Embase, and CNKI databases and comparative studies assessing the accuracy and postoperative efficacy of pedicle screw placement using robotic assistance or freehand techniques in patients with scoliosis were included. The analysis evaluated the accuracy of screw placement, operative duration, intraoperative blood loss, length of postoperative hospital stay, and complications. RESULTS: Seven studies comprising 584 patients were included in the meta-analysis, with 282 patients (48.3%) in the robot-assisted group and 320 (51.7%) in the freehand group. Robot-assisted placement showed significantly better clinically acceptable screw placement results compared with freehand placement (odds ratio [OR]: 2.61, 95% confidence interval [CI]: 1.75-3.91, P < 0.0001). However, there were no statistically significant differences in achieving "perfect" screw placement between the two groups (OR: 1.52, 95% CI: 0.95-2.46, P = 0.08). The robot-assisted group had longer operation durations (mean deviation [MD]: 43.64, 95% CI: 22.25-64.74, P < 0.0001) but shorter postoperative hospital stays (MD: - 1.12, 95% CI: - 2.15 to - 0.08, P = 0.03) than the freehand group. There were no significant differences in overall complication rates or intraoperative blood loss between the two groups. There was no significant difference in Cobb Angle between the two groups before and after operation. CONCLUSION: Robot-assisted pedicle screw placement offers higher accuracy and shorter hospital stay than freehand placement in scoliosis surgery; although the robotics approach is associated with longer operative durations, similar complication rates and intraoperative blood loss.

Electrophotocatalytic Tellurosulfonylation of Alkynes for the Synthesis of ß-(Telluro)vinyl Sulfones.

Difunctionalization of alkynes has gained a lot of interest in current organic chemistry. Herein, we developed an electrophotocatalytic multicomponent cascade reaction of alkynes and indoles with sulfinic acid sodium salts using elemental tellurium as the tellurium source. Using synergistic anodic oxidation and visible-light irradiation, various ß-(telluro)vinyl sulfones have been prepared. This strategy features mild reaction conditions, excellent substrate scope, readily available starting materials, and great functional group tolerance.

Evaluation and Application of Efficient Gelled Acid for Carbonate Formation Fracturing.

In the middle and west of Sichuan Basin, the targeted carbonate formation exhibits features of deep burial and high temperatures at present. In order to obtain better acid fracturing results, the efficient gelled acid developed was investigated based on the carbonate formation characteristics. At the same time, the field application was conducted to prove its adaptability and effectiveness. The high-effective thickener is mainly polymerized by DMC and an allyl octadecyl trimethyl ammonium bromide monomer and a very small amount of diallyl polyethylene glycol. The efficient gelled acid has good compatibility with carbonate formation and formation water, and its thermal stability is great that the viscosity could obtain 25 mPa·s at a temperature of 180 °C after shearing at 30 min. Furthermore, compared with conventional gelled acid, the friction reduction rate of efficient gelled acid is higher of over 7-12%. Also, the induced fracture conductivity is more than 20 D·cm at a closure stress of 60 MPa, which is higher than that of conventional gelled acid with 16.81 D·cm. In addition, during the acidification fracturing of Well PS, the efficient gelled acid system exhibits a good friction reduction property. The flow rate could reach 6 m3·min-1 and the obvious pressure drop could be observed, which indicated that the efficient gelling acid reacted with the carbonate formation, creating acidified fractures. The test production of Well PS is 23 × 104 m3·d-1 and the acid fracturing adopted by the efficient gelled acid obtains a great break at a high-temperature carbonate formation.

Versatile Melanin-Like Coatings with Hierarchical Structure toward Personal Thermal Management, Anti-Icing/Deicing, and UV Protection.

Superhydrophobic photothermal coatings are promising for multifunctional applications due to the efficient use of solar energy, but the current challenge is to seek one easy-to-prepare material with high photothermal performance. Herein, inspired by mussel adhesion and lotus leaf surfaces, we developed superhydrophobic photothermal coatings with hierarchical structure by depositing melanin-like polydopamine (PDA) and dip-coating polydimethylsiloxane (PDMS)/hydrophobic fumed silica (SiO2) sequentially. Benefitting from the efficient photothermal conversion performance of PDA, the coated fabric can rapidly warm up to 100 °C under 100 mW/cm2 sun irradiation. Meanwhile, the coatings show excellent superhydrophobic properties (WCA of 163°), which not only prevent the adhesion of the contaminant from maintaining a long-term and efficient photothermal performance but also help the fabric to own outstanding passive anti-icing and active deicing performances. Furthermore, the superhydrophobic properties of the coatings can be maintained after sandpaper abrasion, repeat tape-peeling, and ultrasonication. In addition, superior UV protection of the coatings can meet the long-term service conditions under outdoor sunlight. The PDA-based superhydrophobic photothermal coatings are believed to inspire new strategies for solar-driven multifunctional applications such as personal thermal management, anti-icing/deicing of variously shaped components, photothermal antibacterial, and so on.

Internet of Everything and Digital Twin enabled Service Platform for Cold Chain Logistics.

The proliferation of the e-commerce market has posed challenges to staff safety, product quality, and operational efficiency, especially for cold chain logistics (CCL). Recently, the logistics of vaccine supply under the worldwide COVID-19 pandemic rearouses public attention and calls for innovative solutions to tackle the challenges remaining in CCL. Accordingly, this study proposes a cyber-physical platform framework applying the Internet of Everything (IoE) and Digital Twin (DT) technologies to promote information integration and provide smart services for different stakeholders in the CCL. In the platform, reams of data are generated, gathered, and leveraged to interconnect and digitalize physical things, people, and processes in cyberspace, paving the way for digital servitization. Deep learning techniques are used for accident identification and indoor localization based on Bluetooth Low Energy (BLE) to actualize real-time staff safety supervision in the cold warehouse. Both algorithms are designed to take advantage of the IoE infrastructure to achieve online self-adapting in response to surrounding evolutions. Besides, with the help of mobile and desktop applications, paperless operation for shipment, remote temperature and humidity (T&H) monitoring, anomaly detection and warning, and customer interaction are enabled. Thus, information traceability and visibility are highly fortified in this way. Finally, a real-life case study is conducted in a pharmaceutical distribution center to demonstrate the feasibility and practicality of the proposed platform and methods. The dedicated hardware and software are developed and deployed on site. As a result, the effectiveness of staff safety management, operational informatization, product quality assurance, and stakeholder loyalty maintenance shows a noticeable improvement. The insights and lessons harvested in this study may spark new ideas for researchers and inspire practitioners to meet similar needs in the industry.

Discrepancy between inter- and intra-subject variability in EEG-based motor imagery brain-computer interface: Evidence from multiple perspectives.

Introduction: Inter- and intra-subject variability are caused by the variability of the psychological and neurophysiological factors over time and across subjects. In the application of in Brain-Computer Interfaces (BCI), the existence of inter- and intra-subject variability reduced the generalization ability of machine learning models seriously, which further limited the use of BCI in real life. Although many transfer learning methods can compensate for the inter- and intra-subject variability to some extent, there is still a lack of clear understanding about the change of feature distribution between the cross-subject and cross-session electroencephalography (EEG) signal. Methods: To investigate this issue, an online platform for motor-imagery BCI decoding has been built in this work. The EEG signal from both the multi-subject (Exp1) and multi-session (Exp2) experiments has been analyzed from multiple perspectives. Results: Firstly we found that with the similar variability of classification results, the time-frequency response of the EEG signal within-subject in Exp2 is more consistent than cross-subject results in Exp1. Secondly, the standard deviation of the common spatial pattern (CSP) feature has a significant difference between Exp1 and Exp2. Thirdly, for model training, different strategies for the training sample selection should be applied for the cross-subject and cross-session tasks. Discussion: All these findings have deepened the understanding of inter- and intra-subject variability. They can also guide practice for the new transfer learning methods development in EEG-based BCI. In addition, these results also proved that BCI inefficiency was not caused by the subject's unable to generate the event-related desynchronization/synchronization (ERD/ERS) signal during the motor imagery.

Comprehensive evaluation of aroma and taste properties of different parts from the wampee fruit.

Wampee is a tropical fruit having high medicinal value. To fully realize the fruit's potential, it is essential to reveal the flavor characteristics. In this study, a comprehensive analysis of the aroma and taste profiles of different parts from the wampee fruit was conducted. The aroma profile was analyzed by E-nose, and 67 volatile components were identified through HS-SPME-GC-MS. Among them, 11 were considered as crucial compounds. Additionally, 42 volatile components were identified by HS-GC-IMS, with 22 compounds showing a variable importance in projection scores greater than 1.0. Moreover, the taste profile and representative compounds were analyzed by E-tongue and HPLC, and 12 compounds were considered as important taste contributors based on taste activity value. These findings shed light on the various compounds responsible for the unique aroma and taste of the wampee fruit, providing theoretical foundation for exploring ways for its comprehensive utilization and development.

Single-cell multimodal imaging uncovers energy conversion pathways in biohybrids.

Microbe-semiconductor biohybrids, which integrate microbial enzymatic synthesis with the light-harvesting capabilities of inorganic semiconductors, have emerged as promising solar-to-chemical conversion systems. Improving the electron transport at the nano-bio interface and inside cells is important for boosting conversion efficiencies, yet the underlying mechanism is challenging to study by bulk measurements owing to the heterogeneities of both constituents. Here we develop a generalizable, quantitative multimodal microscopy platform that combines multi-channel optical imaging and photocurrent mapping to probe such biohybrids down to single- to sub-cell/particle levels. We uncover and differentiate the critical roles of different hydrogenases in the lithoautotrophic bacterium Ralstonia eutropha for bioplastic formation, discover this bacterium's surprisingly large nanoampere-level electron-uptake capability, and dissect the cross-membrane electron-transport pathways. This imaging platform, and the associated analytical framework, can uncover electron-transport mechanisms in various types of biohybrid, and potentially offers a means to use and engineer R. eutropha for efficient chemical production coupled with photocatalytic materials.

The potential for soil C sequestration and N fixation under different planting patterns depends on the carbon and nitrogen content and stability of soil aggregates.

The winter wheat-summer maize rotation system is common in the Huang-Huai-Hai Plain due to its consistent yield, however, it may cause soil quality degradation and increased risk of greenhouse gas emissions. To evaluate the effects of different planting patterns on soil organic carbon (SOC) and total nitrogen (TN) sequestration, as well as aggregate and C-N distribution, a three-year field experiment that included three annual double-cropping rotation patterns: winter wheat-maize (W-M), winter wheat-soybean (W-S), and winter wheat-sweet potato (W-SP) was conducted from 2020 to 2022, with W-M as the control. Our research revealed significant differences in soil carbon sequestration rates among the various planting systems. Specifically, the SOC stock in the W-S system was 12.21 % to 24.51 % higher than that of the W-M system and 10.28 % to 35.73 % higher than that of the W-SP system. While TN stock demonstrated an increase of 9.85 % to 37.39 % compared to the W-M system and 8.14 % to 67.43 % compared to the W-SP system. Moreover, SOC and TN sequestration were largely related to soil aggregates, with macroaggregates being the primary component in both W-S and W-M planting patterns, while microaggregates were more common in W-SP patterns. The accumulation of SOC and TN occurred mainly in macroaggregates, leading to a significant increase in C and N content in soil macroaggregates under the W-S planting pattern. The structural equation model suggested that the TN stock had both direct and indirect effects on SOC sequestration, with a total impact coefficient of 0.872. Our three-year field results indicate that the W-S model is advantageous in enhancing soil C and N sequestration capacity and had great potential in reducing greenhouse gas emissions in farmland.

Investigation and Application of High-Efficiency Network Fracturing Technology for Deep Shale Gas in the Southern Sichuan Basin.

The Longmaxi Formations in the Luzhou block located in the Southern Sichuan Basin exhibit thick shale formations and huge shale gas resources and have become one of the significant blocks for large-scale production of shale gas. However, due to the natural fractures and high in situ stress and horizontal stress differences, proppants are broken and embedded severely, and complex network fractures are difficult to form, so traditional hydraulic fracturing technology cannot meet the need for profitable development of deep shale gas. In order to increase the stimulated reservoir volume and improve fracture complexity, large-scale hydraulic fracturing experiments and fracture propagation numerical simulations have been conducted based on the geology and engineering treatment difficulty of the Luzhou block to discuss the main factors influencing fracturing effectiveness. Meanwhile, two round field tests were conducted to evaluate the fracturing effectiveness, and the following study results were obtained. First, in situ stress and horizontal stress differences are the main mechanical factors, while cluster spacing and proppant injection intensity are the main fracturing parameters. Therefore, multi-cluster perforation, high-intensity proppant injection, and diversion are employed to improve fracture complexity and conductivity, thus increasing effective fracture volume. Furthermore, the second round of field tests gained remarkable results. The "short-cluster spacing + high proppant amount + variable viscosity slick water + diversion" high-efficiency fracturing technology was formed, and the average test production got to 28.6 × 104 m3/d, which represented a 64% increase over the first round. It concludes that the high-efficiency hydraulic fracturing technology contributes to increasing shale gas production, notably in the Luzhou block for deep shale gas, and provides reliable technology support and study direction for further technical optimization in this block.