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Based on the drilling, logging, experimental and testing data of Well PD1, a shallow normal-pressure shale gas well in the Laochangping anticline in southeastern Sichuan Basin, the shallow shale gas reservoirs of the Ordovician Wufeng Formation to Silurian Longmaxi Formation (Wufeng–Longmaxi) were investigated in terms of geological characteristics, occurrence mechanism, and adsorption-desorption characteristics, to reveal the enrichment laws and high-yield mechanism of shallow normal-pressure shale gas in complex structure areas. First, the shallow shale gas reservoirs are similar to the medium–deep shale gas reservoirs in static indicators such as high-quality shale thickness, geochemistry, physical properties and mineral composition, but the former is geologically characterized by low formation pressure coefficient, low gas content, high proportion of adsorbed gas, low in-situ stress, and big difference between principal stresses. Second, shallow shales in the complex structure areas have the gas occurrence characteristics including low total gas content (1.1–4.8 m3/t), high adsorbed gas content (2.5–2.8 m3/t), low sensitive desorption pressure (1.7–2.5 MPa), and good self-sealing. Third, the adsorbed gas enrichment of shales is mainly controlled by organic matter abundance, formation temperature and formation pressure: the higher the organic matter abundance and formation pressure, the lower the formation temperature and the higher the adsorption capacity, which is more beneficial for the adsorbed gas occurrence. Fourth, the shallow normal-pressure shale gas corresponds to low sensitive desorption pressure. The adsorbed gas can be rapidly desorbed and recovered when the flowing pressure is reduced below the sensitive desorption pressure. Fifth, the exploration breakthrough of Well PD1 demonstrates that the shallow complex structure areas with adsorbed gas in dominance can form large-scale shale reservoirs, and confirms the good exploration potential of shallow normal-pressure shale gas in the margin of the Sichuan Basin. [ABSTRACT FROM AUTHOR]

Extracting high-accuracy landslide areas using deep learning methods from high spatial resolution remote sensing images is a hot topic in current research. However, the existing deep learning algorithms are affected by background noise and landslide scale effects during the extraction process, leading to poor feature extraction effects. To address this issue, this paper proposes an improved mask regions-based convolutional neural network (Mask R-CNN) model to identify the landslide distribution in unmanned aerial vehicles (UAV) images. The improvement of the model mainly includes three aspects: (1) an attention mechanism of the convolutional block attention module (CBAM) is added to the backbone residual neural network (ResNet). (2) A bottom-up channel is added to the feature pyramidal network (FPN) module. (3) The region proposal network (RPN) is replaced by guided anchoring (GA-RPN). Sanming City, China was selected as the study area for the experiments. The experimental results show that the improved model has a recall of 91.4% and an accuracy of 92.6%, which is 12.9% and 10.9% higher than the original Mask R-CNN model, respectively, indicating that the improved model is more effective in landslide extraction. [ABSTRACT FROM AUTHOR]

The discovery of an oil reservoir in Pishan Caldera of the Tarim Basin, northwest China, highlights the hydrocarbon exploration potential of large calderas. We used 3 D seismic interpretations, waveform clustering analysis, and seismic profiles to investigate the origin and evolution of Pishan Caldera, along with the mechanisms of hydrocarbon accumulation, and its significance for future oil and gas exploration. Pishan Caldera is located at depths of >7000 m, has an elliptical shape, extends over an area of 25 × 20 km, and is surrounded by ring faults. Pishan Caldera were the result of magma withdrawal and later magma intrusion. Volcanic eruptions, caldera collapse, and reactivation of Pishan Caldera resulted in Cretaceous oil migration and accumulation in Cretaceous breccia reservoirs. Ring faults, dense fracture networks, and lava tubes associated with the caldera acted as conduits for upward hydrocarbon migration. We propose a generalized model for hydrocarbon reservoirs related to the caldera, which includes five major reservoir types: drape anticline, fault block, volcanic-trapped, laterally sealed and lava tube type. Further efforts should be made to identify deep caldera structures that may be targets for hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

Under the conditions of straw returning operation, there are three major technical bottlenecks in the Phaeozem region of northeast China, namely low stubble breaking rate, poor tillage depth consistency, and high fuel consumption. In this research, a bionic stubble-deep loosening combined tillage machine (BSD) was designed through bionic prototype analysis, coupled bionic analysis, coupled bionic design, theoretical analysis and application of intelligent control techniques. It consists of a bionic stubble breaking device and a bionic self-excited vibratory deep loosening device. Based on the unique biting pattern of locust mouthparts on maize rootstocks, the bionic stubble breaking device adopted a new multi-segment serrated bionic structure and a symmetrical rotational motion, which could significantly increase the stubble breaking rate (p<0.05) and reduce the resistance to stubble breaking operations (p<0.05). Based on the unique biology of the hare's paws, toes and nails, the bionic self-excited vibration deep loosening device adopted a new series-parallel composite bionic elastic system and an intelligent tilling depth control system with a fuzzy algorithm, which significantly improved the tilling depth consistency (p<0.05). The operational performance of the BSD was verified at different operating speeds through comparative experiments and reveals the mechanism of its excellent performance through theoretical analysis. The final experiment results showed that, at the same operating speed, the BSD improved the stubble breaking rate by 9.62% and 10.67%, reduced the stubble breaking torque by 28 N·m and 33 N·m, reduced the tillage depth coefficient of variation by 12.73% and 13.48%, and reduced the specific fuel consumption by 36 g/km·h and 40 g/km·h compared to the two most common models. The operating performance of the three kinds of machines will decrease with the increase of operating speed, and the BSD has the least decrease. [ABSTRACT FROM AUTHOR]

Lung cancer is the malignant tumor with the highest morbidity and mortality in China. Non-small cell lung cancer is the main pathological type. Lymph node metastasis is the most common and primary metastatic pathway in non-small cell lung cancer. Acknowledged as the major factor determining tumor staging and prognosis. Unfortunately, it's presently hard to make an accurate preoperative judgment on the lymph node metastasis of early stage non-small cell lung cancer. Consequently, there has been a long-standing controversy on lymph node sweeping for early stage non-small cell lung cancer, especially for those clinical stage I. The regularity of non-small cell lung cancer lymph node metastasis and the ways of lymph node sweeping will be reviewed in this paper. [ABSTRACT FROM AUTHOR]

Canopy temperature (Tc) measurements with infrared thermometry have been widely used to assess plant water status. Here, we evaluated Tc and its controlling factors in a primary tropical rainforest (TRF), subtropical evergreen broad-leaved forest (STF) and valley savanna forest (SAF) in southwestern China. We found differences between Tc and air temperature (Ta) of as much as 2.2 °C between the dry and wet seasons in the TRF. However, the canopy-to-air temperature difference (Tc-Ta) was only 0.3 °C between the dry and wet seasons in the STF. Solar radiation (SR) was the dominant factor in Tc-Ta variations during the dry and wet seasons at the three sites. The increased heating in the canopy leaves was likely the result of low stomatal conductance leading to low transpiration cooling. Changes in Tc-Ta in the TRF were highly sensitive to the degree of stomatal closure. The change in Tc-Ta was controlled by the climate, but inherent plant traits, such as stomatal conductance, also played an important controlling role. [ABSTRACT FROM AUTHOR]

The Tarim Basin was a craton block during the Carboniferous period. Except for its open southwestern (SWW) deepening basin margin, the central part of the basin was surrounded by northern, eastern, and southern uplifts. In most parts of the basin, there are three layers of carbonate rocks called Biocalcarenite member, standard limestone member and Xiaohaizi Formation. The present-day Maigeti slope, located in the southwestern area of the basin, was ever a paleogeographic carbonate platform margin to clinoform. Boreholes in the area reveal over ten meters of high-energy biospararenite of beach deposition in Xiaohaizi Formation. This feature is quite different from the low-energy micritic limestone of equivalent horizon in the middle and northern basins. Such typical carbonate beach and platform margin backgrounds indicate an environment conducive for reef growth. According to an interpretation of 3-D seismic data on a 600 km Xinbaza survey, a 25 km-long barrier reef orientated in an east-westward direction is delineated with a hummocky geometry, a 1-2 km wide south-dip reef front, and a 3-6 km wide north-dip backreef. The reef buttress and outlines are also shown on an isopach map of the Xiaohaizi Formation as well as horizon slices of coherency, amplitude, and frequency attributes. The reef extends beyond the range of the rectangular 3-D seismic survey. The thickness of the Xiaohaizi Formation is over 60 m at the central reef, and 12 m larger than the outside of the reef. The barrier reef consists of segments separated by narrow tidal inlets. The neighborhood of the reef is mainly beach deposition of bioclasticgrainstones. Due to Late Permier and Late Tertial tectonic movements, the barrier reef was tilted to dip in a SWW direction. Its updip part was broken and misplaced by a set of reverse faults. Nevertheless, potential stratigraphic pools of a large amount of hydrocarbon reserves related to the reef are expected to be found in the future based on the substantial reef scale and the recent borehole indications beside it. [ABSTRACT FROM AUTHOR]

We identified a Neogene rapid uplift-denudation event of the South Tianshan based on apatite (U-Th)/He and apatite fission track (AFT) ages in Tertiary rocks of the Tarim basin, using borehole samples. The (U-Th)/He thermochronology can be used to reveal the tectono-thermal events with lower temperature than that of AFT thermochronology and has not been used previously to study the uplift of the Tianshan Mountain. Using these data, we show the relationship between the uplift of the South Tianshan and the subsidence/deposition of the northern Tarim basin during the Neogene. The apatite helium ages reveal the migration of uplift, erosion and deposition in the northern Tarim basin. A rapid uplift of the South Tianshan during the Miocene and a corresponding rapid subsidence in the northern Tarim basin occurred. However, in the Pliocene, the Kuqa Depression and South Tianshan uplifted and eroded at the same time and in turn provided the detrital source rocks for the Northern Uplift of the Tarim basin. In contrast to earlier studies, we arrive at the conclusion that the South Tianshan experienced rapid uplift in the Miocene based on (U-Th)/He data of apatite obtained from borehole samples collected in the Tarim basin itself, and not from the bordering mountain chain. Combined apatite (U-Th)/He and fission track thermochronometry enables reconstruction of thermal histories of sedimentary rocks between 40 and 120°C, and this has implications for the generation of liquid hydrocarbon in the 65-120°C range in the basin. Thermal and burial histories of typical samples were also modelled to show the rapid uplift in our study. Our works not only provide a new evidence for the South Tianshan uplift but also indicate that there is a coupling between uplift and subsidence in the South Tianshan and adjacent northern part of the Tarim basin, which controlled hydrocarbon accumulation in the Kuqa Depression and Northern Uplift of the Tarim basin. [ABSTRACT FROM AUTHOR]

The management of congenital heart disease (CHD) remains a significant challenge in developing regions. Since 2006, China California Heart Watch has provided cardiac services in China's Yunnan province. Our Grants for Kids program aims to diagnose and fund surgical and nonsurgical treatments for underprivileged children with congenitally malformed hearts. This report analyzes our patient outcomes. From 2007 to 2010, 36 children with CHD underwent either surgical or percutaneous procedures at local Chinese medical centers, and 94% of our patients could be contacted for follow-up assessment. The mortality and complication rates of our patient population compare favorably with international data. Our study provides a model through which networking with local hospitals and regional cardiac centers can be an effective way to assist developing areas in providing cardiac care to rural underserved populations. [ABSTRACT FROM AUTHOR]

Little research exists that explores families with HIV/AIDS. The purpose of this exploratory multiple case study is to explore the experiences of five Chinese families affected by AIDS contracted during blood transfusions. Longitudinal qualitative data were collected from five families with a member who had contracted HIV from blood received during a medical procedure. Six themes emerged that represented the six stages experienced by our strong families: reeling in disbelief, placing blame, turning to acceptance, searching for help, finding meaning, and becoming a helping group. Findings resulted in a model that reveals the critical turning point that put our families onto a trajectory of either positive or negative outcomes. The model also identifies the point at which a transformation took place in our strong families — finding meaning and a sense of inner peace which led to outward expressions of becoming a helping group. This study has implications for social workers and advocates of strengthening families affected by HIV/AIDS. [ABSTRACT FROM AUTHOR]

The purpose of this exploratory case study was to describe the needs and present the voices of 21 AIDS-infected individuals who contracted the disease through the selling of blood in rural China. Data sources included interviews, field notes, and letters. Three themes emerged: living in a vicious circle, awakening from the dead end, and escaping the vicious circle through education. Education emerged as an overarching theme and was identified as the catalyst that would either keep the families of those affected trapped in the vicious circle or rescue them from it. Findings are explained within the theoretical contexts of social capital, motivation theory, and Confucius's philosophy on education. The authors discuss implications for researchers, educators, relief workers, human service workers, policy makers, and human rights advocates. They conclude with suggestions for further study. [ABSTRACT FROM AUTHOR]

Background: Caroli syndrome (CS) is a rare congenital disorder without pathognomonic clinical symptoms or laboratory findings; therefore, the diagnosis is often delayed. The objective of this study was to investigate the diagnostic delay and associated risk factors in CS patients.Methods: This was a retrospective analysis of 16 CS patients admitted to a single tertiary medical center on mainland China. The diagnostic timelines of CS patients were reviewed to demonstrate the initial findings of CS at diagnosis, the risk factors associated with diagnostic delay, and potential clues leading to early diagnosis.Results: The median diagnostic delay was 1.75 years (range: 1 month to 29 years, interquartile range: 6.2 years) in 16 enrolled CS patients. Sex, age, and initial symptoms were not associated with diagnostic delay. 87.5% of CS patients were diagnosed by imaging, and the accuracies of ultrasonography, computed tomography (CT), and magnetic resonance cholangiopancreatography were 25, 69.2, and 83.3%, respectively. The median diagnostic delays for patients with or without CT performed at the first hospital visited according to physician and radiologist suspicion of the diagnosis were 7.4 months and 6 years, respectively (p = 0.021). Hepatic cysts with splenomegaly were detected by ultrasound in over half of CS patients.Conclusions: The majority of CS patients were not diagnosed until complications of portal hypertension had already developed. Recognition and early suspicion of the disease were important factors influencing diagnostic delay of CS. Hepatic cysts plus splenomegaly detected by US might raise the clinical suspicion to include CS in the differential diagnosis. [ABSTRACT FROM AUTHOR]

Newly discovered superdeep marine carbonate reservoirs with burial depths of more than 7000 m are found in the Shuntuo Low Uplift, Tarim Basin, China. Previous exploration experience indicates that strike-slip faults in these deposits played a key role in reservoir formation and hydrocarbon accumulation. This paper describes the structural and hydrocarbon characteristics of the SB5M strike-slip fault zone in the Shuntuo Low Uplift based on the study of high-quality 3-D seismic volumes and drilling data. The SB5M fault is a repeatedly reactivated strike-slip vertical fault zone. In the Paleozoic strata, the SB5M strike-slip fault zone is composed of sub-vertical strike-slip faults in the deep layer, a graben structure in the middle layer, and en-echelon normal faults in the shallow layer. The deep, middle and shallow faults developed sequentially at different times and formed as a result of three-stage evolution: the Middle Caledonian, Late Caledonian, and Middle-Late Hercynian. Fracture networks formed by repeated fault activity provided pathways for karst flow and hydrocarbons, which are conducive to the formation of fracture–cavity reservoirs. Due to the fault damage zone-fault core transition and the complex structural features, the reservoirs controlled by the SB5M strike-slip fault zone feature strong heterogeneity. The data sets presented and evolution models established in this paper provide important data for the exploration and development of the SB5M strike-slip fault zone and represent references for structural analysis and hydrocarbon exploration of strike-slip fault zones in the Tarim Basin and elsewhere. • Intracratonic strike-slip faults in Tarim Basin control the development of deep carbonate reservoirs. • The data sets in this paper provide important data for study a small-displacement intracratonic strike-slip fault. • This study represents a reference for structural analysis and hydrocarbon exploration of intracratonic strike-slip fault. [ABSTRACT FROM AUTHOR]

There are abundant local chronicles in the Qing Dynasty, which provide rich literature for the research on the production of medicinal materials. This paper collates the contents of Fuling in the local chronicles of the Qing Dynasty to reveal the distribution of Fuling in China at that time. The distribution of Fuling in the local chronicles of the Qing Dynasty involved 318 county-level regions in 23 provinces. The distribution records were mainly found in Yunnan, Anhui, Hunan, Zhejiang, Fujian, Jiangxi, Shaanxi, and Hubei. The local chronicles of the Qing Dynasty showed that Yunnan was the Dao-di producing area of Fuling, which was consistent with the materia medica of the Ming and Qing Dynasties. In the Qing Dynasty, the quality of Fuling in Dabie Mountains of Anhui was excellent, and it was called &quot;Anling&quot;. The development of Anling benefited from the introduction of planting technology from Yunnan and the development of characteristic cultivation technology, with the formation of a complete industrial chain covering planting, processing, and sales. The abundant historical materials of Fuling in the local chronicles of the Qing Dynasty provide not only a documentary basis for revealing the changes of the Dao-di producing areas but also a historical context for the development of modern Fuling-producing areas such as Fujian, Jiangxi, and Hunan. In addition to the information of producing areas, the local records recorded the quality, commodity evaluation, and cultivation techniques of Fuling, filling the gaps in ancient materia medica books and providing detailed historical materials for understanding the producing areas and application of Fuling in the Qing Dynasty.

Strontium isotope(~(87)S/~(86)Sr) tracing technology has been widely used in animal remains and origin of modern food origin sources. However, due to the problems of sample contamination and cleaning, this technology has been applied less frequently in the tracing of plant remains. The Palace Museum preserves more than 1 000 relics of medicinal materials from the Forbidden City of the Qing Dynasty, which are rare precious materials for the study of Dao-di herbs. The well-preserved environment of these medicinal materials in the Forbidden City of the Qing Dynasty helps avoid external strontium contamination, making it possible to introduce strontium isotope technology in their tracing research. On this basis, this study discussed the principle of strontium isotope tracing technology and summarized the current research progress on tracing plant remains using strontium isotope. In addition, this study discussed three key problems and their respective solutions encountered when applying strontium isotope technology to the tracing research on medicinal materials from the Forbidden City of the Qing Dynasty: creating strontium isotope ratio maps, dealing with the wide range of traceable results, and addressing the sample contamination and cleaning challenges. The literature and historical materials of the Qing Dynasty are the important basis for understanding the distribution and application of Dao-di herbs in the Qing Dynasty. Based on literature research, the use of strontium isotope to trace the producing area of medicinal materials in the Forbidden City of the Qing Dynasty can provide physical evidence for relevant research. The combined evidence of historical materials and medicinal relics is expected to provide a new perspective for the study of Dao-di herbs in the Qing Dynasty and also provide a reference for the study of the revolution of Dao-di herbs producing areas.

We analyzed COVID-19 influences on the design, implementation, and validity of assessing the quality of primary health care using unannounced standardized patients (USPs) in China. Because of the pandemic, we crowdsourced our funding, removed tuberculosis from the USP case roster, adjusted common cold and asthma cases, used hybrid online-offline training for USPs, shared USPs across provinces, and strengthened ethical considerations. With those changes, we were able to conduct fieldwork despite frequent COVID-19 interruptions. Furthermore, the USP assessment tool maintained high validity in the quality checklist (criteria), USP role fidelity, checklist completion, and physician detection of USPs. Our experiences suggest that the pandemic created not only barriers but also opportunities to innovate ways to build a resilient data collection system. To build data system reliance, we recommend harnessing the power of technology for a hybrid model of remote and in-person work, learning from the sharing economy to pool strengths and optimize resources, and dedicating individual and group leadership to problem-solving and results. ( Am J Public Health . 2022;112(6):913-922. https://doi.org/10.2105/AJPH.2022.306779).

A pot experiment was conducted to study the CH4 emission features of fourteen leading super-rice varieties (six Japonica rice varieties and eight Indica hybrid rice varieties) and their relationships with the varieties growth characteristics in Yangtze Delta. Two distinct peaks of CH4 emission were detected during the entire growth period of the varieties, one peak occurred at full-tillering stage, and the other appeared at booting stage. The average total CH4 emission of Japonica rice varieties was 37.6% higher than that of the Indica hybrid rice varieties (P<0.01), and the differences in the CH4 emission between rice types occurred at the post-anthesis phase. For all the varieties, there was a significant positive correlation between the total CH4 emission and the maximum leaf area, but the correlations between the CH4 emission and the other growth characteristics varied with variety type. The total CH4 emission of Japonica rice varieties had a significant positive correlation with plant height, while the correlations between the total CH4 emission of Indica hybrid rice varieties and their plant height were not significant. The total CH4 emission of Indica hybrid rice varieties had significant negative correlations with the total aboveground biomass, grain yield, and harvest index, but the correlations were not significant for Japonica rice varieties. The lower CH4 emission of Indica hybrid rice varieties was likely due to their significantly higher root biomass, as compared with Japonica rice varieties.