Acyl oximes are directly used as the acyl radical precursors in the hydroacylation reactions for the first time. In this work, acyl radicals can be effectively generated via β-scission of a ...phosphoranyl radical under photocatalytic conditions. As a result, the hydroacylation of alkenes triggered by the resulting acyl radicals leads to facile syntheses of a range of valuable ketones.
Immunoassays and liquid chromatography tandem mass spectrometry (LC-MS/MS) are two major methods for therapeutic drug monitoring (TDM) of immunosuppressant drugs. Compared to the relatively limited ...analytical performance and cross reactivities of immunoassays, the LC-MS/MS method is considered as a gold standard; however, the lack of systematic evaluation and standardization needs to be addressed.
A LC-MS/MS method for the determination of cyclosporine A, sirolimus, tacrolimus, and everolimus was developed. One-step protein precipitation was used to prepare blood samples. The newly developed method was systematically evaluated and validated according to the standard guidelines.
The quantitative method for four immunosuppressant drugs in human whole blood was validated according to the guidelines. The lower limits of the measuring interval (LLMI) for cyclosporine A, sirolimus, tacrolimus, and everolimus were 5, 0.5, 0.5, and 0.5 ng/mL, respectively. Linear correlation coefficients were all >0.999. Internal standard-normalized (IS-normalized) matrix correction factor was within the range 0.88–1.17. The average spiked recoveries of five replicates for the four immunosuppressant drugs were in the range 87.4–109.6%.
An LC-MS/MS method combined with one-step protein precipitation was developed, providing short sample preparation and chromatographic run time, thus allowing easy clinical diagnosis.
•A straightforward LC-MS/MS method was developed for determination of four immunosuppressant drugs.•One-step protein precipitation was used to deal with the blood samples, which was easy and high throughput.•Systematic evaluation were validated to access the method strictly according to the guidelines
Objective
To explore the correlation between the fracture line inferior plane and perioperative deep venous thrombosis (DVT) in patients with tibial fractures.
Methods
Data was collected from the ...medical records of 536 consecutive patients with tibial fractures at Xi’an Honghui Hospital. The patients were divided into distal, shaft, and proximal segment groups according to the fracture line inferior plane on radiographs. Multivariate logistic regression models were used to identify the role of the inferior plane of the fracture line in perioperative DVT.
Results
A total of 431 patients were included in the study and 226 patients had perioperative DVT in the lower extremities, including 11 proximal and 215 distal DVTs. Univariate regression analysis showed a significant correlation between the proximal segment and perioperative DVT; however, no correlation was found in the shaft segment group. Additionally, age, coronary heart disease, associated injuries, and time to operation ≥6 days were risk factors for perioperative DVT. However, fixation with intramedullary nails may be a protective factor for perioperative DVT compared with plates. After adjusting for potential confounding factors, the proximal segment group had an increased incidence of perioperative DVT compared to the distal segment group.
Conclusions
The proximal segment may be correlated with an increased incidence of perioperative DVT by 7.30-fold in patients with tibial fractures compared to that in the distal segment. In clinical practice, surgeons should be vigilant for DVT formation in these patients.
Palaeoproterozic metasedimentary rocks, also referred to as khondalites, characterized by Al-rich minerals, are extensively exposed in the nucleus of the Yangtze craton, South China block. Samples of ...garnet–sillimanite gneiss in the khondalite suite were collected from the Kongling complex for Nd isotopic and elemental geochemical study. These rocks are characterized by variable SiO2 contents ranging from 35.71 to 58.07 wt%, and have low CaO (0.45–0.84 wt%) but high Al2O3 (18.56–29.04 wt%), Cr (174–334 ppm) and Ni (42.5–153 ppm) contents. They have high CIW (Chemical Index of Weathering) values (90.4–94.7), indicating intense chemical weathering of the source material. The samples display light rare earth elements (LREE) enrichment with negative Eu anomalies (Eu/Eu*=0.40–0.68), and have flat heavy rare earth elements (HREE) patterns. The high contents of transition elements (e.g. Cr, Ni, Sc, V) and moderately radiogenic Nd isotopic compositions suggest that the paragneisses might be those of first-cycle erosion products of predominantly mafic rocks mixing with small amounts of felsic moderately evolved Archaean crustal source. Geochemical and Nd isotopic compositions reveal that at least some of the protoliths of Kongling khondalite were sourced from local pre-existing mafic igneous rocks in a continental arc tectonic setting. Combined with documented zircon U–Pb geochronological data, we propose that the Palaeoproterozoic high-pressure granulite-facies metamorphism, rapid weathering, erosion and deposition of the khondalites in the interior of the Yangtze craton might be related to a Palaeoproterozoic collisional orogenic event during 2.1–1.9 Ga, consistent with the worldwide contemporary orogeny, implying that the Yangtze craton may have been an important component of the Palaeoprotorozoic Columbia supercontinent.
A comprehensive geochronological and geochemical study was carried out on the gneissic monzogranites, porphyritic granodiorites and charnockites in the Gaozhou complex of the Yunkai massif in the ...southern part of the South China block to better understand the Early Palaeozoic tectonic regime of the South China block. Laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) U–Pb dating of zircons indicates an age of 453.2 ± 5.1 Ma to the formation of the gneissic monzogranites, whereas the porphyritic granodiorites and charnockites were generated at 437.0 ± 1.5 Ma and 435.2 ± 2.2 Ma, respectively. The gneissic monzogranites show geochemical features consistent with the high-K, calc-alkaline rock series and are strongly peraluminous. They have SiO2 contents ranging from 67.75 to 69.65 wt. % and relatively low CaO contents (1.66–1.94 wt. %). Their REE patterns are fractionated with enriched LREEs and negative Eu anomalies. The samples also show enrichment in LILEs (e.g. Rb and K) and Pb, and depletion in Sr, Ba and HFSEs (e.g. Nb, Ta, Ti and P). They have εNd(t) values of −8.2 to −7.7. Conversely, the porphyritic granodiorites and charnockites are characterized as medium-K, calc-alkaline rock series and weakly to strongly peraluminous. They exhibit pronounced depletions in HFSEs and positive Pb anomalies. Compared to the earlier gneissic monzogranites, these rocks have relatively lower SiO2 (65.50–69.36 wt. %), but higher CaO contents (3.34–4.05 wt. %), and have slightly lower εNd(t) values (−9.1 to −8.4). Petrography and geochemical compositions of the gneissic monzogranites indicate that they are S-type granite and likely formed by partial melting of Neoproterozoic to Early Palaeozoic immature metagreywackes; whereas The porphyritic granodiorites and charnockites are A-type granite and likely derived from low degrees of partial melting of the dry, granulitic residue depleted by prior extraction of granitic melt. The new data for the Caledonian granitoids in the Yunkai massif suggest that they were formed in a post-collisional tectonic setting. They represent the earliest post-collisional alkaline magmatism reported so far in the Yunkai massif, and thus indicate a tectonic regime switch, from compression to extension, as early as the Late Ordovician to Early Silurian (~450–435 Ma).
A quantitative method was developed for the detection of phosphorus (P) and sulfur (S) in complex biological samples by inductively coupled plasma mass spectrometry (ICP-MS) with Dynamic/Reaction ...Cell (DRC) technology. P and S concentrations were measured at m/z 47 as PO+ and m/z 48 as SO+, respectively, in a reaction cell with oxygen (O2) to reduce the effect of polyatomic isobaric interferences at m/z 31 for P and m/z 32 for S. To correct the measured concentrations of P and S, several common internal standard elements such as Li, Sc, Rh and In were evaluated in detail for the first time. DRC mode operating conditions were optimized by changing oxygen flow rate and Rejection Parameter q (RPq). The limits of detection for P and S were as low as 0.173 μg L-1 and 1.26 μg L-1. Finally, Samples of serum, blood plasma and whole blood from healthy individuals, ten in each group, were analyzed for P and S using the proposed method. These findings can provide important reference value for diagnosis of diseases or poisoning caused by P or S disorders.
A quantitative method for the detection of phosphorus (P) and sulfur (S) in complex biolgical samples by inductively coupled plasmamass spectrometrywith Dyanmic/Reaction Cell (DRC) technology was described. O2was used and optimized for product ions PO and SO to reduce the effect of polyatomic isobaric interferences for P and S detection. Several commoninternal standard elements. Samples of serum, blood plasma and bloodfrom healthy individuals were analyzed in this work, which provided important reference value for diagnosis of diseases or posioning caused by P or Sdisorder. Display omitted
•Simultaneous determination of P and S in complex biolgical samples.•Common internal standard elements were discussed for the first time to correct the measured concentrations for P and S.•Samples of serum, plasma and blood from healthy individuals, ten in each group, were analyzed in this work.
Phosphorus （P） is one of the most widely occurring nutrients for development and growth of wheat. In this study, the effects of P application amount on grain yield, protein content, and phosphorus ...use efficiency （PUE） were studied by agronomic management of P fertilizer on spring weak-gluten wheat （Triticum aestivum L.） grown under field conditions for 2 yr. The experiments were performed at five levels of P205 application amount, including 0, 72, 108, 144, and 180 kg ha-1. As a result, with increase in P fertilizer, grain yield, and P agricultural efficiency （AEp） increased in a quadratic equitation, but partial factor productivity of P （PFPp） decreased in a logarithmic eq. When 108 kg ha-1 P2Os was applied, the grain yield reached the highest level, but the protein content in gain was lower than 11.5%, a threshold for the protein content to evaluate weak-gluten wheat suitable for production of cake and biscuit. Yangmai 13 and Ningmai 9 could tolerate to higher P level of soils than Yangmai 9 that had more loss in grain yield when P fertilizer was over-applied. AEp had a concomitant relationship with grain yield and was a better descriptor for P use efficiency in the wheat. A high P use efficiency resulted in leaf area index （LAI）, increased chlorophyll content and photosynthetic rate, and stable acid phophatase （APase） activity to accumulate more dry matter after anthesis, which explained that the optimum P fertilizer increased grain yield and improved grain quality of weak-gluten wheat.
Tuberculosis (TB) remains one of the major infectious diseases in the world with a high incidence rate. Drug-resistant tuberculosis (DR-TB) is a key and difficult challenge in the prevention and ...treatment of TB. Early, rapid, and accurate diagnosis of DR-TB is essential for selecting appropriate and personalized treatment and is an important means of reducing disease transmission and mortality. In recent years, imaging diagnosis of DR-TB has developed rapidly, but there is a lack of consistent understanding. To this end, the Infectious Disease Imaging Group, Infectious Disease Branch, Chinese Research Hospital Association; Infectious Diseases Group of Chinese Medical Association of Radiology; Digital Health Committee of China Association for the Promotion of Science and Technology Industrialization, and other organizations, formed a group of TB experts across China. The conglomerate then considered the Chinese and international diagnosis and treatment status of DR-TB, China's clinical practice, and evidence-based medicine on the methodological requirements of guidelines and standards. After repeated discussion, the expert consensus of imaging diagnosis of DR-PB was proposed. This consensus includes clinical diagnosis and classification of DR-TB, selection of etiology and imaging examination mainly X-ray and computed tomography (CT), imaging manifestations, diagnosis, and differential diagnosis. This expert consensus is expected to improve the understanding of the imaging changes of DR-TB, as a starting point for timely detection of suspected DR-TB patients, and can effectively improve the efficiency of clinical diagnosis and achieve the purpose of early diagnosis and treatment of DR-TB.
A novel ultra-high-strength bainitic steel was designed.The analysis of its mechanical properties by quasistatic testing showed that upper bainitic steel exhibited an ultimate tensile strength of 2 ...260 MPa（engineering stress）and an ultimate compressive strength of more than 2 700MPa（true stress）.The ultra-high strength of upper bainitic steel was mainly attributed to untempered martensite and upper bainite with a feather-like microstructure.Moreover,lower bainitic steel demonstrated an ultimate tensile strength of 1 922 MPa（engineering stress）and an ultimate compressive strength of 2 500MPa（true stress）.The ultra-high strength of lower bainitic steel was primarily due to untempered martensite and lower bainite with an acicular microstructure.The untempered martensite in the two kinds of bainitic steels was produced in different ways.The dynamic test results showed that the ultimate compressive strengths of the two bainitic steels were maintained at 1 600MPa（true stress）under high strain rates（1 100and2 200s-1）at 600℃,because of the added tungsten,confirming the satisfactory hot hardness property of the steel.Furthermore,lower bainitic steel showed better comprehensive mechanical properties than upper bainitic steel.
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