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Titanoniobate nanosheets with thickness down to a few nanometers have been prepared by ion exchange and subsequent exfoliation treatment on a bulk layer compound KTiNbO5. Superior photocatalytic H2 production activity has been realized on these nanosheets, surpassing their mother compound KTiNbO5. More interestingly, their photocatalytic activity has been successfully extended into visible light region when Cr/Nb co-dopants are introduced into nanosheets. The Cr/Nb modified nanosheets show apparent quantum efficiency as high as 2.75% at 420 ± 20 nm for H2 production, outperforming a number of doped metal oxides photocatalysts. Such high photocatalytic activity origins from their tiny thickness and a much enlarged surface area that favors charge separation and transfer. Their little dependence on cocatalyst for H2 production suggest that dopants Cr may also serve as catalytic reaction sites as a substantial fraction of Cr dopants are accommodated at the surface. This facile approach to fabricate ultrathin 2D semiconductor as well as versatility of doping strategy open new playground for the design and development of efficient visible light active photocatalysts.

The study of the late Neo-Proterozoic tectono-sedimentary evolution of the Tarim Basin is a key to unravel the tectonic setting, the intracontinental rift formation mechanism, and the sedimentary filling processes of this basin. Since in the Tarim Basin, the late Neo-Proterozoic to early Cambrian sedimentary successions were preserved, this basin represents an excellent site in order to study the Precambrian geology. Based on the outcrop data collected in the peripheral areas of the Tarim Basin, coupled with the intra-basinal drill sites and seismic data previously published, the late Neo-proterozoic tectono-sedimentary evolution of the Tarim Basin has been investigated. These data show that there were two individual blocks before the Cryogenian Period, namely, the north Tarim Block and the south Tarim Block. In the early Neo-Proterozoic (ca. 800 Ma), the amalgamation of two blocks resulted in the formation of the unified basement. During the late Neo-Proterozoic, the Tarim Block was in an extensional setting as a result of the Rodinia supercontinent breakup and then evolved into an intracontinental rift basin. The tectono-sedimentary evolution of the basin may be divided into three stages: the rifting stage (780–700 Ma), the rifting to depression transitional stage (660–600 Ma), and the post-rift depression stage (580–540 Ma). In the rifting stage, intracontinental rifts (i.e., the Awati Rift, the North Manjar Rift, and the South Manjar Rift) were formed, in which coarse-grained clastic sediments were deposited, generally accompanied by a massive volcanic activity due to an intensive stretching. In the rifting-depression transitional stage and in the post-rift depression stage, the paleogeography was characterized by uplifts to the south and depressions to the north. Three types of depositional association (i.e., clastic depositional association, clastic-carbonate mixed depositional association, and carbonate depositional association) were formed. The distribution of the lower Cambrian source rock was genetically related to the tectono-sedimentary evolution during the late Neo-Proterozoic. The lower Cambrian source rock was a stable deposit in the northern Tarim Basin, where the late Ediacaran carbonate was deposited, thinning out toward the central uplift. It was distributed throughout the entire Mangar region in the east and may be missing in the Magaiti and the southwestern Tarim Basin.

Porous single-crystalline SrTaO2N, combining structural homogeneity and high porosity, afford a great promise as an active photocatalyst. The lack of grain boundaries in SrTaO2N porous single crystals (PSCs) enables fast photocarrier migration from bulk to the surface whilst the high porosity offers adequate accessible surface to perform photocatalytic reactions. In this work, we demonstrate a facile synthesis of SrTaO2N PSCs via a topotactic conversion route. These SrTaO2N PSCs deliver exceptional activity and stability for photocatalytic O2 production from water with a record-breaking apparent quantum efficiency as high as 17.9% at 420 ± 20 nm. Overall water splitting with H2/O2 equals 2 has also been attained in a Z-scheme system employing SrTaO2N PSCs as the O2-evolution moiety. These results signify a paradigm to improve photocatalytic performance based on PSCs, which extends the toolbox to achieve efficient solar water splitting over conventional photocatalysts.

Background: Knowledge on the pharmacodynamic effects of antiplatelet drugs including clopidogrel and ticagrelor on Asian patients is scarce. We aim to evaluate the effects of the two drugs on platelet reactivity in the treatment of Chinese patients who underwent percutaneous coronary intervention (PCI), using two platelet function tests (PFT). Meanwhile, the relationship between mean platelet volume (MPV), a routinely index of platelet size, and high on-treatment platelet reactivity (HPR) is also investigated.Methods: Patients receiving dual antiplatelet therapy (DAPT) treatment were scheduled for the assessment of platelet reactivity at 2-3 days after PCI. Two PFTs, light transmission aggregometry (LTA) and vasodilator-stimulated phosphoprotein (VASP) assay, were applied in the evaluation of platelet reactivity. MPV was measured simultaneously.Results: The final study population included the traditional therapy group with aspirin and clopidogrel (n = 46) and the new therapy group with aspirin and ticagrelor (n = 66). In the new therapy group, the value of platelet aggregation assessed by LTA was obviously lower than that in the traditional therapy group (P < 0.001). The platelet reactivity index (PRI) level at VASP test was also markedly lower in the group given the new therapy (P < 0.001). It presented significant difference of HPR rates between the two groups. MPV showed a potent ability in predicting the presence of HPR at VASP assay (AUC = 0.788, 95% CI: 0.701-0.875, P < 0.001) in receiver-operating characteristic curve analysis.Conclusions: Compared with clopidogrel, ticagrelor has dramatically greater antiplatelet effect, with a superiority of suppressing platelet function and a lower HPR rates. In addition, there existed a significantly independent association between MPV and high prevalence of HPR at VASP assay.

Item does not contain fulltext Background Prostate MRI is used widely in clinical care for guiding tissue sampling, active surveillance, and staging. The Prostate Imaging Reporting and Data System (PI-RADS) helps provide a standardized probabilistic approach for identifying clinically significant prostate cancer. Despite widespread use, the variability in performance of prostate MRI across practices remains unknown. Purpose To estimate the positive predictive value (PPV) of PI-RADS for the detection of high-grade prostate cancer across imaging centers. Materials and Methods This retrospective cross-sectional study was compliant with the HIPAA. Twenty-six centers with members in the Society of Abdominal Radiology Prostate Cancer Disease-focused Panel submitted data from men with suspected or biopsy-proven untreated prostate cancer. MRI scans were obtained between January 2015 and April 2018. This was followed with targeted biopsy. Only men with at least one MRI lesion assigned a PI-RADS score of 2-5 were included. Outcome was prostate cancer with Gleason score (GS) greater than or equal to 3+4 (International Society of Urological Pathology grade group >/=2). A mixed-model logistic regression with institution and individuals as random effects was used to estimate overall PPVs. The variability of observed PPV of PI-RADS across imaging centers was described by using the median and interquartile range. Results The authors evaluated 3449 men (mean age, 65 years +/- 8 [standard deviation]) with 5082 lesions. Biopsy results showed 1698 cancers with GS greater than or equal to 3+4 (International Society of Urological Pathology grade group >/=2) in 2082 men. Across all centers, the estimated PPV was 35% (95% confidence interval [CI]: 27%, 43%) for a PI-RADS score greater than or equal to 3 and 49% (95% CI: 40%, 58%) for a PI-RADS score greater than or equal to 4. The interquartile ranges of PPV at these same PI-RADS score thresholds were 27%-44% and 27%-48%, respectively. Conclusion The positive predictive value of the Prostate Imaging and Reporting Data System was low and varied widely across centers. (c) RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Milot in this issue.

In this paper, a comparative study of the effectiveness of deep neural networks (DNNs) in the classification of pure and impure purees is conducted. Three different types of deep neural networks (DNNs)—the Gated Recurrent Unit (GRU), the Long Short Term Memory (LSTM), and the temporal convolutional network (TCN)—are employed for the detection of adulteration of strawberry purees. The Strawberry dataset, a time series spectroscopy dataset from the UCR time series classification repository, is utilized to evaluate the performance of different DNNs. Experimental results demonstrate that the TCN is able to obtain a higher classification accuracy than the GRU and LSTM. Moreover, the TCN achieves a new state-of-the-art classification accuracy on the Strawberry dataset. These results indicates the great potential of using the TCN for the detection of adulteration of fruit purees in the future.

Transmission towers and substations are used in a variety of natural environments, coupled with the interference of the surrounding production and life, facing the test of soil corrosion. Based on the experimental data of 72 soil samples from five cities in Southern Hebei Province, the soil resistivity, soil pH value and soil moisture content were investigated, and the soil corrosion grade and soil corrosion grade distribution map were obtained. It provides a reference for the collection of soil corrosivity data in power transmission and transformation projects.

Many of the current clinical screening methods for prostate cancer (PCa) such as prostate-specific antigen (PSA) testing or transrectal ultrasound-guided prostate biopsy lack sensitivity and specificity for diagnosis of PCa of the transition zone (TZ). Recent technical advances in multiparametric-MRI have markedly improved detection of PCa of the TZ. However, there are many diagnostic challenges that we still encounter in our daily practice that compromise the accuracy of the diagnosis. By performing both MRI-guided and ultrasound/MRI fusion-guided biopsies, we have gained extensive experience in the diagnosis of PCa of the TZ. Biopsy-proven examples including but not limited to typical and atypical PCa of the TZ as well as a wide variety of its mimics will be presented. Recognition of the MR features of typical and atypical PCa of the TZ and its mimics on multiparametric-MRI along with findings that help to differentiate these mimics from PCa is important in establishing an accurate diagnosis and in guiding clinical management.

Starting from two wide band gap semiconductors AgTaO3 and SrTiO3, we managed to reduce the band gap by forming their solid solutions, i.e. (AgTaO3)1-x(SrTiO3)x (0.0 ≤ x ≤ 1.0). These solid solutions all adopt cubic perovskite structure similar to SrTiO3 and high temperature phase of AgTaO3, suggesting that SrTiO3 is helpful to stabilize AgTaO3 in its high temperature cubic phase. Substantial improvements over photocatalytic hydrogen production were realized in these solid solutions which clearly outperform their parent compounds AgTaO3 and SrTiO3. In-situ exolution of silver nanoparticles at the surface of solid solutions (x = 0.2) substantially strengthen the visible light absorption due to localized surface plasmons of these silver nanoparticles. This contributes to further improvements on both photocatalytic hydrogen and oxygen production under visible light illumination (λ ≥ 400 nm). Apparent quantum efficiency as high as ˜ 2.02% and ˜ 0.11% was achieved at solid solutions (x = 0.2) decorated with silver nanoparticles for full range (λ ≥ 250 nm) and visible light (λ ≥ 400 nm) illumination respectively. Photoelectrochemical analysis suggests that solid solutions own a better charge separation conditions than their parent compounds. Furthermore, the band edge positions of solid solutions (x = 0.2) lie approximately in the middle between AgTaO3 and SrTiO3, being ideal for solar water splitting reactions.

Recent advances in magnetic resonance imaging (MRI) have made imaging the biliary tract faster while providing excellent anatomic reproduction of this duct system. MRI/MR-cholangiopancreatography (MRCP) has now become the first-line imaging procedure for many biliary tract problems. This work briefly discusses the MR techniques for biliary tree imaging and reviews MRI's role in the numerous diagnoses of filling defects in the biliary tract.

Word embeddings have attracted much attention recently. Different from alphabetic writing systems, Chinese characters are often composed of subcharacter components which are also semantically informative. In this work, we propose an approach to jointly embed Chinese words as well as their characters and fine-grained subcharacter components. We use three likelihoods to evaluate whether the context words, characters, and components can predict the current target word, and collected 13,253 subcharacter components to demonstrate the existing approaches of decomposing Chinese characters are not enough. Evaluation on both word similarity and word analogy tasks demonstrates the superior performance of our model.

The oxidation behavior of (Mo 0.85 Nb 0.15 )Si 2 single crystals and the influence of Cr-addition were studied focusing on its microstructure dependence. Cr-addition to single-phase C40-structured (Mo 0.85 Nb 0.15 )Si 2 crystal induced the formation of crystalline silica, leading to slightly larger weight gain during the oxidation test at 1200 °C. Furthermore, Cr-addition to C40/C11 b duplex-phase (Mo 0.85 Nb 0.15 )Si 2 crystal with lamellar structure strongly suppressed the internal oxidation of the C11 b phase, resulting in excellent oxidation resistance. C40/C11 b lamellae-structured crystals showed better oxidation resistance than the C40-structured crystals.

One in six males will develop prostate cancer during their lifetime. Prostate cancer is the second leading cause of cancer death in American males, behind only lung cancer. Unfortunately, even though this disease is so common, clinical screening methods such as prostate-specific antigen test and transrectal ultrasound-guided prostate biopsy lack sensitivity and specificity in diagnosing prostate cancer. In recent years, multiparametric prostate MRI has emerged as a very important tool in the diagnosis of prostate carcinoma with a high accuracy. However, diagnostic difficulty is often encountered even with an experienced abdominal radiologist. That is mainly because many normal and abnormal entities can mimic prostate carcinoma at multiparametric MRI. Therefore, the purpose of this pictorial review is to discuss the usefulness of multiparametric prostate MRI in the diagnosis of prostate carcinoma, emphasizing the key MRI features that help to make a distinction of prostate carcinoma from its mimics.

AIM: To determine the magnetic resonance cholangiopancreatography (MRCP) and magnetic resonance imaging (MRI) features of pancreatitis with pancreas divisum (PD) and the differences vs pancreatitis without divisum. METHODS: Institutional review board approval was obtained and the informed consent requirement was waived for this HIPAA-compliant study. During one year period, 1439 consecutive patients underwent successful MRCP without injection of secretin and abdominal MRI studies for a variety of clinical indications using a 1.5 T magnetic resonance scanner. Two experienced radiologists retrospectively reviewed all the studies in consensus. Disputes were resolved via consultation with a third experienced radiologist. The assessment included presence and the imaging findings of PD, pancreatitis, and distribution of abnormalities. The pancreatitis with divisum constituted the study group while the pancreatitis without divisum served as the control group. MRCP and MRI findings were correlated with final diagnosis. Fisher exact tests and Pearson × 2 tests were performed. RESULTS: Pancreatitis was demonstrated at MRCP and MRI in 173 cases (38 cases with and 135 cases without divisum) among the 1439 consecutive cases. The recurrent acute pancreatitis accounted for 55.26% (21 of 38) in pancreatitis patients associated with PD, which was higher than 6.67% (9 of 135) in the control group, whereas the chronic pancreatitis was a dominant type in the control group (85.19%, 115 of 135) when compared to the study group (42.11%, 16 of 38) (χ2 = 40.494, P < 0.0001). In cases of pancreatitis with PD, the dorsal pancreatitis accounted for a much higher percentage than that in pancreatitis without PD (17 of 38, 44.74% vs 30 of 135, 22.22%) (χ2 = 7.257, P < 0.05). CONCLUSION: MRCP and MRI can depict the features of pancreatitis associated with divisum. Recurrent acute pancreatitis and isolated dorsal involvement are more common in patients with divisum.

Biochemical recurrence after treatment for prostate cancer (PCa) is a significant issue. Early diagnosis of local recurrence is important for making prompt treatment decisions and is strongly associated with patient prognosis. Without salvage therapy, the average time from development of local recurrence to distant metastasis is approximately 3 years. Biochemical recurrence does not differentiate local recurrence from systemic disease; there is no reliable way to clinically diagnose local recurrence. Recent advances in multiparametric MRI (mp-MRI) techniques have markedly improved detection of local recurrence following therapy. However, a wide variety of entities can mimic recurrent PCa at mp-MRI. Therefore, the purpose of this pictorial review is to discuss the MRI findings of locally recurrent PCa and its mimics, emphasizing the key MRI features that help to differentiate local recurrence from its mimics.

Multiparametric-MRI is an important tool in the diagnosis of prostate cancer (PCa), particularly diffusion-weighted imaging for peripheral zone (PZ) cancer in the untreated prostate. However, there are many benign entities that demonstrate diffusion restriction in the PZ mimicking PCa resulting in diagnostic challenges. Fortunately, these benign entities usually have unique MR features that may help to distinguish them from PCa. The purpose of this pictorial review is to discuss benign entities with diffusion restriction in the PZ and to emphasize the key MR features of these entities that may help to differentiate them from PCa.