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Based on the daily Japanese 55-year Reanalysis (JRA-55) dataset, this study reveals that southern Europe/western Asia (SEWA) and northern China are two large-scale regions that have exhibited consistent interdecadal variations in the frequency of persistent hot events (PHEs). Over the past 58 summers, the period approximately from 1973 to 1996 represents an inactive period for the occurrence of PHEs over the two regions, whereas the antecedent and subsequent periods are active periods. At the subseasonal time scale, the regional PHEs over SEWA are characterized by quasi-stationary wave train anomalies aloft from the northwest Atlantic to Europe, while the regional PHEs over northern China are characterized by quasi-stationary wave train anomalies over the Eurasian continent. The persistence of the quasi-stationary anomalies is associated with the Rossby wave propagation. Moreover, the energy extraction from the basic flow is also favorable for their persistence. Our study reveals that the above typical circulation anomalies for the PHEs over both SEWA and northern China are in phase with the background circulation changes during the two active periods. Thus, the interdecadal changes in background circulation can modulate the frequency of PHEs over the two regions simultaneously. Further analysis reveals that the background circulation changes are closely related to the interdecadal variation in the Silk Road pattern based on their similarities in both spatial pattern and temporal variation. The sea surface temperature over four particular regions seems to facilitate the phase shifts in the Silk Road pattern on the interdecadal time scale. [ABSTRACT FROM AUTHOR]

Background: Malignancy probability models for pulmonary nodules (PN) are most accurate when used within populations similar to those in which they were developed. Our goal was to develop a malignancy probability model that estimates the probability of malignancy for PNs considered high enough risk to recommend biopsy.Methods: This retrospective analysis included training and validation datasets of patients with PNs who had a histopathologic diagnosis of malignant or benign. Radiographic and clinical characteristics associated with lung cancer were collected. Univariate logistic regression was used to identify potential predictors. Stepdown selection and multivariate logistic regression were used to build several models, each differing according to available data.Results: Two hundred malignant nodules and 101 benign nodules were used to generate and internally validate eight models. Predictors of lung cancer used in the final models included age, smoking history, upper lobe location, solid and irregular/spiculated nodule edges, emphysema, fluorodeoxyglucose-PET avidity, and history of cancer other than lung. The concordance index (C-index) of the models ranged from 0.75 to 0.81. They were more accurate than the Mayo Clinic model (P < .05 for four of the models), and each had fair to excellent calibration. In an independent sample used for validation, the C-index for our model was 0.67 compared with 0.63 for the Mayo Clinic model. The ratio of malignant to benign nodules within each probability decile showed a greater potential to influence clinical decisions than the Mayo Clinic model.Conclusions: We developed eight models to help characterize PNs considered high enough risk by a clinician to recommend biopsy. These models may help to guide clinicians' decision-making and be used as a resource for patient communication. [ABSTRACT FROM AUTHOR]

Based on the Japanese 55-year reanalysis daily data, this study finds that the frequency of persistent cold events from Lake Balkhash to Lake Baikal exhibits a clear interdecadal variation. Circulation characteristics, such as interdecadal variations in regional persistent cold event frequencies, are the focus of this study. During the 57-year period, a subperiod from the mid-1980s to the late 1990s exhibits inactive characteristics compared with those before and after during the study period. On a subseasonal timescale, the typical circulation patterns of persistent cold events are characterized by wave-train anomalies across the Atlantic Ocean and Eurasian continent, with significantly positive height anomalies that persist over the Ural Mountains in the upper troposphere, positive SLP anomalies over Eurasian mid- to high latitudes and cold SAT anomalies from Lake Balkhash to Lake Baikal. The changes in background circulation at the interdecadal timescale correspond well with the typical circulation patterns at the subseasonal timescale, indicating their important role in modulating the frequency of persistent cold events. Interdecadal changes in the background circulation can be partially explained by transient eddy feedback forcing. [ABSTRACT FROM AUTHOR]

Soil quality of garden plants is an important factor for good growth of garden plants. Based on the analysis of the current situation of garden soil, the ecological value and feasibility of composting technology applied in garden soil improvement were discussed. This study provided a basis for strengthening the quality management of garden soil, improving the standard of garden soil improvement, and helping the healthy and sustainable development of modern garden greening. [ABSTRACT FROM AUTHOR]

Mammalian cells are surrounded by neighbouring cells and extracellular matrix (ECM), which provide cells with structural support and mechanical cues that influence diverse biological processes1. The Hippo pathway effectors YAP (also known as YAP1) and TAZ (also known as WWTR1) are regulated by mechanical cues and mediate cellular responses to ECM stiffness2,3. Here we identified the Ras-related GTPase RAP2 as a key intracellular signal transducer that relays ECM rigidity signals to control mechanosensitive cellular activities through YAP and TAZ. RAP2 is activated by low ECM stiffness, and deletion of RAP2 blocks the regulation of YAP and TAZ by stiffness signals and promotes aberrant cell growth. Mechanistically, matrix stiffness acts through phospholipase Cγ1 (PLCγ1) to influence levels of phosphatidylinositol 4,5-bisphosphate and phosphatidic acid, which activates RAP2 through PDZGEF1 and PDZGEF2 (also known as RAPGEF2 and RAPGEF6). At low stiffness, active RAP2 binds to and stimulates MAP4K4, MAP4K6, MAP4K7 and ARHGAP29, resulting in activation of LATS1 and LATS2 and inhibition of YAP and TAZ. RAP2, YAP and TAZ have pivotal roles in mechanoregulated transcription, as deletion of YAP and TAZ abolishes the ECM stiffness-responsive transcriptome. Our findings show that RAP2 is a molecular switch in mechanotransduction, thereby defining a mechanosignalling pathway from ECM stiffness to the nucleus. The Ras-related GTPase RAP2 is a key intracellular signal transducer by which extracellular matrix rigidity controls mechanosensitive cellular activities through YAP and TAZ. [ABSTRACT FROM AUTHOR]

Because of the shortage of donors, alveolar stem cells transplantation is under development as an important and promising treatment for end-stage lung disease. Currently, the acquisition of functional lung cells is mostly performed by two dimensional (2D) culture and suffers from low directed differentiation efficiency. It is particularly critical to replicate the three dimensional (3D) growth of lung cells, as cells grow in 3D microenvironment in vivo. In this work, we develop a 3D biomimetic composite hydrogel system based on the in situ crosslinking of the synthetic polymer 4 arm acrylated-poly(ethylene glycol) (4PEG-AC), the thiolated natural polymer hyaluronic acid (HA-SH), and the thiolated polypeptide (GSE4-SH) via a Michael-type "click" reaction under physiological conditions at pH 7.8. The PEG/HA/GSE4 hydrogel with a sheer modulus of 104.1 ± 9.9 Pa was used for 3D growth of bone marrow mesenchymal stem cells (BMSCs), displaying excellent biocompatibility. Covalent conjugation of GSE4 peptide in hydrogel promoted the differentiation of BMSCs into alveolar epithelial type 2 cells (AEC2s) with a AEC2s-differentiation rate of 58.6 ± 3.3%. Overall, this study provides a suitable 3D biomimetic platform to enable the efficient differentiation of stem cells into lung cells for lung tissue engineering. [Display omitted] • Michael-type "click" reaction was employed to fabricate a biocompatible and biodegradable HA/PEG hydrogel. • Thiolated GSE4 Peptide was designed and chemically conjugated into 3D HA/PEG hydrogel matrix. • GSE4 Peptide incorporated in PEG/HA hydrogel promotes the AEC2s-Differentiation of BMSCs. • PEG/HA/GSE4 hydrogel provides a 3D platform to enable the efficient differentiation of stem cells into lung cells. [ABSTRACT FROM AUTHOR]

The study of the shale rocks' fracturing characteristics reveal general guidelines for hydraulic fracturing processes in shale reservoirs, and the microseismic information provides a direct reflection of the fracturing process. Acoustic emission (AE) testing of rocks in the laboratory can be used for the application of microseismic information acquired in the field. Therefore, uniaxial compression experiments were performed to study AE characteristics during the failure process in shale rocks. In this study, the number of AE hits, along with the energy, a-values and b-values, were used to characterise the AE data and to describe the rock's rupture behaviour. The testing results indicated that the AE rates and energy values increased markedly when slippage occurred and these parameters reflect the generation of micro-cracks in the rock. The b and a-value curves can be divided into four stages corresponding with the fracture processes. The changes in the b and a -values can indicate the distribution characteristics of cracks within the rock. Based on this theory, the AE characteristics from dry and water-saturated shale samples under uniaxial compression were compared to demonstrate that water diffuses pressure in the rock and promotes fracture network generation. The b-values in the elastic-yield stage increase along with the brittleness index, and the b-values in the post-peak stage can offset the limitations of brittleness indexes used in evaluations of reservoir fracability. Exploring the law of rupture for shale under pressure provides a foundation for microseismic-based quantitative evaluation of the hydraulic fracturing stimulation efforts in shale reservoirs; therefore, this knowledge has both scientific and engineering significance. [ABSTRACT FROM AUTHOR]

In order to effectively evaluate the complex fracture network forming ability of Fengcheng Formation shale oil reservoirs in Mahu sag, the core in a vertical well of Fengcheng Formation in Mahu sag was considered as the research object. Through coring sampling, indoor experimental testing, combined with logging data and comprehensive interpretation, the rock mechanical properties and in-situ stress profile of the reservoir are systematically obtained. The results show that the shale oil reservoir of Fengcheng Formation in Mahu sag has deep burial depth, large absolute value of in-situ stress, high compressive strength and elastic modulus, good brittleness, low development degree of reservoir bedding, but relatively developed natural fractures. Among these features, brittleness, natural fractures, compressive strength and in-situ stress are the main controlling factors affecting the reservoir fracture propagation. The acoustic emission b value during the process of rock fracture can characterize the ability to form complex fracture network. By evaluating the correlation coefficient between each main control factor and acoustic emission b value for the first time, the weight value of each factor on fracture forming ability is determined. So as to establish the quantitative evaluation model of reservoir fracture forming ability, and quantitatively evaluate the fracture forming ability of the reservoir section. Applying the quantitative evaluation model of fracture forming ability to the logging data of the well. The evaluation results of the whole well section are consistent with the liquid production profile of the well, which shows that the research model established by this method is reliable. That also provides a guidance for the fracturing transformation and horizon optimization of horizontal wells in Fengcheng Formation shale oil reservoir in Mahu sag in the later stage. • A set of rock mechanical property parameters of the reservoir of Fengcheng Formation in Mahu sag are first obtained. • The main controlling factors affecting reservoir fracture propagation are determined. • A set of compressibility evaluation method suitable for the reservoir of Fengcheng Formation is established. [ABSTRACT FROM AUTHOR]

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative option for patients with myelofibrosis (MF). Bone marrow (BM) morphologic evaluation of myelofibrosis following allo-HSCT is known to be challenging in this context because resolution of morphologic changes is a gradual process. We compared BM samples of patients with myelofibrosis who underwent first allo-HSCT and achieved molecular remission by day 100 with BM samples of patients who continued to have persistent molecular evidence of disease following allo-HSCT. The study group included 29 patients: 17 primary MF, 7 post-polycythemia vera (PV) MF, and 5 post-essential thrombocythemia (ET) MF. In this cohort there were 18 JAK2 p.V617F, 8 CALR ; 1 MPL , and 2 patients had concurrent JAK2 p.V617F and MPL mutations. The control group included 5 patients with primary MF, one with post-PV MF, one with post-ET MF (5 JAK2 p.V617F; 2 CALR). Following allo-HSCT, both groups showed reduction in BM cellularity and number of megakaryocytes. The study cohort also less commonly had dense megakaryocyte clusters and endosteal located megakaryocytes and showed less fibrosis. There was no statistical difference in BM cellularity, presence of erythroid islands, degree of osteosclerosis, or megakaryocyte number, size, nuclear lobation, presence of clusters or intrasinusoidal location. Following allo-HSCT at 100 days, morphologic evaluation of BM in patients with MF cannot reliably predict persistence versus clearance of molecular evidence of MF. Disappearance of BM MF, dense megakaryocyte clusters, and endosteal localization of megakaryocytes are suggestive of disease response. • Reversal of the bone marrow morphologic features of MF often lags behind following allo-HSCT and may create diagnostic challenges in disease surveillance. • It was impossible reliably to predict whether an individual patient has achieved a complete molecular remission based on morphologic examination of bone marrow at day 100 post allo=HSCT. • The disappearance of high-grade bone marrow fibrosis, large clusters of megakaryocytes, and endosteal localization of megakaryocytes are reassuring findings, suggestive of disease response. • Persistence of hypercellularity, increased numbers of megakaryocytes, the presence of intrasinusoidal megakaryocytes, and osteosclerosis should not be interpreted as a lack of response to allo-HSCT or disease recurrence. [ABSTRACT FROM AUTHOR]

The propagation of multiple fractures plays a significant role in the effectiveness of hydraulic stimulation in shale oil reservoirs. Previous studies reported that the laminations and bedding interface in shale oil rocks could influence the propagation of single hydraulic fracture. However, the propagation mechanism of multiple fractures in such rocks is still unclear. Here we use a true-triaxial experimental system, together with the acoustic emission (AE) monitoring system, to investigate the propagation of multiple fractures in shale oil reservoir rocks. The results show that the fracture interference started at the initiation stage seriously affects the propagation of multiple fractures. More clusters per stage could aggravate the fracture interference near the wellhead. The laminations and bedding interfaces are the main causes of fracture interference and could hinder the height of hydraulic fractures. Shear-type AE event signals the generation of fracture interference caused by the slip of bedding interface and the deflection of fractures induced by the laminations. The mechanism of fracture interference not only lies in stress shadow but also in the changes in fluid pressure caused by the high permeability of laminations and bedding interface. The experimental results provide basic and detailed data for studying hydraulic fracturing in shale oil reservoirs. Highlights: True-triaxial experiment is conducted to investigate the propagation of multiple hydraulic fractures. Both the lamination and bedding interface influence multiple hydraulic fracture propagation. The AE monitoring indicates many shear-type fractures when fracture interference appears. [ABSTRACT FROM AUTHOR]

The oxygen environments of Fe+3-δ ions determine the magnetic anisotropy of M-type ferrites. The high annealing temperature increases the oxygen content and decreases the lattice strain in M-type SrFe9.4Cu0.8Sn0.5O19-d ferrites. The anisotropic field and the coercive field decrease with the increasing annealing temperature. Annealed at 1400 °C, a ferromagnetic resonance is observed at the frequency above 9.5 GHz, with the real part having a peak and the imaginary part of the permeability having a high plateau over a wide frequency range. It enables the microwave energy' dissipation by the magnetic loss. Furthermore, the extra oxygen ions ease up the dipole polarizations' rotation and significantly increase the dielectric permittivity. At thin thickness of 1.3 mm, the effective absorption bandwidth (R L ≤ − 10 dB) of SrFe9.4Cu0.8Sn0.5O19-d annealed at 1400 °C is 7.1+ GHz from 10.9 to 18+ GHz. SrFe9.4Cu0.6Sn0.6O19-d annealed at 1400 °C has the microwave absorption bandwidth of 8.8 GHz from 9.2 to 18+ GHz at 1.6 mm. Both are very promising microwave absorbing materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dual-emission ratio fluorescent sensor (N-CDs/R-CDs@ZIF-8) was developed for Pb2+. • Spinach served as carbon source for green preparation of red fluorescent CDs. • Ultrasensitive Pb2+ detection down to 4.78 nM was delivered. A novel dual-emission ratio fluorescent sensor (N-CDs/R-CDs@ZIF-8) has been constructed successfully by introducing nitrogen-doped blue fluorescence carbon dots (N-CDs) and red fluorescence carbon dots (R-CDs) into the synthetic environment of ZIF-8 by a simple stirring method. The synthesized material not only inherits the excellent optical properties of N-CDs and R-CDs and the strong adsorption and accumulation performance of ZIF-8, but also shows strong fluorescence and structural stability in extreme environments. The presence of Pb2+ strongly causes the fluorescence quenching of N-CDs, but has almost no effect on the fluorescence of R-CDs. Therefore, a ratio fluorescence sensor is developed for the determination of Pb2+. Most importantly, the real-time fluorescence response shows that the composite material has a high selectivity and good sensitivity to Pb2+ determination, and the calculated LOD is 4.78 nM(S/N = 3) (0.05–50 μM), indicating that the material can be used as a potential fluorescent sensor for Pb2+ detection. [ABSTRACT FROM AUTHOR]

Background: To explore potential value of guard-wire technology during percutaneous coronary intervention (PCI) in patients with ostial coronary lesions.Methods: Patients, who underwent PCI, were collected between October 2011 and March 2017. Of the 141 patients, 63 (44.7%) have ostial lesions, and 78 (55.3%) have distal bifurcation sites. They were divided into group A (n = 71) and group B (n = 70). Group A received PCI after guard-wire technology. Group B were given balloon dilation and stent after placing guide wire through target lesion vessel. X-ray exposure time, contrast agent dosage, total PCI duration, pressure incarceration times, cases of malignant arrhythmia and cases of failed PCI of all patients were analyzed, respectively.Results: The general clinical characteristics includes patients age, sex ratio, the proportion of complications, smoking ratio and left ventricular ejection fraction of both groups was not significantly different. X-ray exposure time, contrast agent dosage, PCI total time, stent positioning time, pressure infestation frequency, arrhythmia frequency and complication number of group B were higher than those of group A. There is no case of malignant arrhythmia and case of failed PCI in group A, while there were five malignant arrhythmia and four failed PCI in group B. Contrast agent dosage and cases of failed PCI increased in group B compared with group A.Conclusion: The guard wire technology is safer and more feasible to patients with ostial coronary lesions who underwent PCI. [ABSTRACT FROM AUTHOR]