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Molybdenum‐based efficient and broadly applicable catalytic system is presented for the dehydrogenative coupling of γ‐/β‐amino alcohols with ketones. In particular, complex Mo(CO)6 in combination with Xantphos and t‐BuOK as base provides direct synthesis of structurally diverse quinoline, pyridine, and pyrrole compounds (total 55 examples) with isolated yields up to 92%. Low catalyst loading, cost‐effective, and high catalytic activities with high tolerance to stand with diverse functional groups are additional features of these molybdenum catalysts exhibiting high efficacy to replace the precious metal catalysts such as ruthenium and iridium. Furthermore, the DFT and experimental studies were explored for the reaction mechanism which can assist in broadening the scope of the molybdenum catalysts for different transformation reactions. [ABSTRACT FROM AUTHOR]

Coseismic frictional heating and associated hydrothermal fluid circulation play an essential role in the dynamic weakening of seismic faults. However, temperature rise induced by frictional heating during an earthquake is still difficult to constrain. Magnetic properties of fault rocks convey abundant information on faulting processes. In this study, detailed rock magnetic measurements in combination with electron microscopic observations are conducted on fault rocks and protoliths from the Shaba outcrop (Beichuan County) on the Yingxiu‐Beichuan Fault ruptured during the 2008 Wenchuan Mw 7.9 earthquake. Results show that protoliths and the majority of fault rocks are dominated by paramagnetic pyrite and/or Fe‐bearing clay minerals; in contrast, the presence of pyrrhotite and goethite is confined to the fault gouges just next to the principal slip surface. Pyrrhotite is a product of pyrite alteration at high temperatures (>500°C) induced by seismic frictional heating during earthquake slip. Meanwhile, the goethite implies the presence of coseismic hot fluids within the fault zone. All these observations strongly suggest the occurrence of thermal pressurization as a plausible mechanism of coseismic fault weakening during the Wenchuan earthquake.Plain Language Summary: As the products of faulting processes, physical and chemical properties of fault rocks convey important information for understanding the faulting processes. Iron, as the fourth most abundant element in the earth's crust, widely occurs in fault zones as iron‐oxides, ‐hydroxides, and/or ‐sulfides. Moreover, these Fe‐bearing (magnetic) minerals are sensitive to stress‐strain, temperature change, and fluid activity. Here, detailed rock magnetic analyses in combination with electron microscopic observations are conducted on the fault rocks and protoliths from the Shaba outcrop (Beichuan County) on the Yingxiu‐Beichuan Fault hosting the 2008 Wenchuan Mw 7.9 earthquake. It is found that pyrrhotite and goethite are only present and confined to the fault gouges just next to the principal slip surface. Their formation is resulted from the alteration of the pre‐existing pyrite and Fe‐bearing clay minerals driven by coseismic frictional heating and concomitant hot fluids. These results suggest the occurrence of thermal pressurization that played an essential role in coseismic weakening during the earthquake. Thus, it demonstrates that the rock magnetic properties of fault rocks could provide valuable insights into faulting‐related physical and chemical processes.Key Points: Pyrite thermally altered to pyrrhotite at >500°C induced by coseismic frictional heating in fault gouges from the Yingxiu‐Beichuan FaultGoethite precipitated as a result of hydrothermal leaching of the pre‐existing pyrite and Fe‐bearing clay minerals by coseismic hot fluidsPresence of pyrrhotite and goethite reveals the essential role of thermal pressurization in fault weakening during the Wenchuan earthquake [ABSTRACT FROM AUTHOR]

Based on DEA model, the wholesale efficiency of 14 cities in Liaoning province was measured. From the perspective of input and output, the wholesale efficiency of each city in Liaoning Province was systematically studied to evaluate the development of the wholesale industry in Liaoning Province. The results show that the wholesale efficiency in Liaoning province is generally low, but the returns to scale are increasing. The efficiency level varies greatly among different cities, and the reasons for non-DEA effective wholesale investment in different cities are different.

The ever-evolving Internet technology has brought more information resources for music teaching than ever before. For music educators, figuring out how to create and use these tools more effectively has become a pressing concern. China will usher in a new age of innovation and integration between the Internet and different traditional businesses with the idea of "Internet Plus." MOOCs present significant challenges to traditional teachers and teaching methods as a typical practice of the transformation of education informatization to innovation, and they also drive global education toward a new process of informatization development. This paper adopts Internet thinking as the guiding ideology for the development of future music education concepts and, concurrently, conducts specific transformation research based on Internet technology from four aspects: music teaching content, music teaching methods, music education concepts, and the passing down of traditional music culture. The improved association rule algorithm is used to organise the students' access data, decide which high-frequency websites are accessible to the students, and realize the intuitive positioning of high-frequency access and learning issues. Assist the school's decision-making and educational levels in identifying the issues that students have with their learning, and then, improve the network teaching platform's material to complete the task of personalized network education. [ABSTRACT FROM AUTHOR]

Reconstructing past changes in the oceanic nitrate inventory with sedimentary N records in the South China Sea (SCS), which is the terminal of North Pacific Intermediate Water (NPIW), has regional and global implications. However, water‐column nitrate cycling that affects N isotope preservation remains poorly understood in the SCS. We present a new data set of nitrate isotopes (δ15NNO3 ${\delta }^{15}{\mathrm{N}}_{{\text{NO}}_{3}}$ and δ18ONO3 ${\delta }^{18}{\mathrm{O}}_{{\text{NO}}_{3}}$) to elucidate nitrate dynamics in the SCS and the adjoining western North Pacific Ocean (wNPO). Greater increases in δ18ONO3 ${\delta }^{18}{\mathrm{O}}_{{\text{NO}}_{3}}$ than in δ15NNO3 ${\delta }^{15}{\mathrm{N}}_{{\text{NO}}_{3}}$ are observed in the SCS euphotic zone, suggesting a combined effect of partial nitrate assimilation and nitrification. In the subsurface and thermocline waters of both regions, upward disproportional decreases in δ15NNO3 ${\delta }^{15}{\mathrm{N}}_{{\text{NO}}_{3}}$ and δ18ONO3 ${\delta }^{18}{\mathrm{O}}_{{\text{NO}}_{3}}$ accompanied by elevated nitrate anomalies (N*) indicate an accumulation of external N. Such changes are less significant in the SCS due to higher nitrate concentrations therein, although external N influxes are comparable in both regions. High δ15NNO3 ${\delta }^{15}{\mathrm{N}}_{{\text{NO}}_{3}}$ and δ18ONO3 ${\delta }^{18}{\mathrm{O}}_{{\text{NO}}_{3}}$ values in the wNPO intermediate water result from the lateral transport of NPIW with isotopically more enriched nitrate from the remote denitrification zones followed by mixing with overlying water containing isotopically depleted nitrate. As NPIW flows into the SCS, its isotopically enriched signal is further diluted by strong vertical mixing with overlying and underlying waters in the interior. Compared to its source water from the wNPO, the SCS deep water has consistent nitrate isotopic compositions but significantly lower N*, indicating increased benthic denitrification at the wNPO margins with an estimated rate of 0.26–0.41 mmol N m−2 day−1. Plain Language Summary: The South China Sea (SCS) is an ideal region to study past changes in the oceanic N pool using sedimentary N records. These records are sensitive to water‐column nitrate cycling. This study presents a new data set of nitrate isotopes in the SCS and the neighboring western North Pacific Ocean, the aim of which is to determine major processes controlling their distribution. Partial nitrate consumption by phytoplankton and nitrate production from ammonium/nitrite oxidation by microorganisms together determine nitrate isotopes in the upper 100 m of the SCS. Atmospheric‐derived and biologically fixed N that provides lighter nitrate isotopes mainly accumulates in the subsurface water (100–400 m). In deeper waters, the distribution of nitrate isotopes in the SCS is regulated by a vertical sandwich‐like water flow structure through the Luzon Strait, that is westward inflows of the North Pacific waters in the upper (<750 m) and deep (>1,500 m) layers and an eastward outflow of SCS waters between the two layers. Strong vertical mixing in the SCS interior further smooths the original nitrate isotopes. Our findings highlight the important role of these biogeochemical and physical processes in governing water‐column nitrate isotopes and thus sedimentary N records in the SCS. Key Points: Nitrate δ15N and δ18O increase unequally in the South China Sea (SCS) surface water due to partial nitrate assimilation and nitrificationExternal N inputs lower δ15N and δ18O of subsurface nitrate to a lesser extent in the SCS than in the western North Pacific Ocean (wNPO)Lateral exchange between SCS and wNPO intermediate and deep waters along with vertical mixing modifies their nitrate isotopic composition [ABSTRACT FROM AUTHOR]

Background: Deep vein thrombosis (DVT) is common among patients with stroke. However, the incidence of DVT in acute ischemic stroke patients treated with thrombolytic therapy and the risk factors associated with this condition are unknown. Objective: This study aimed to investigate the incidence and risk factors of DVT after thrombolysis in patients with acute ischemic stroke. Settings and Methods: We retrospectively reviewed the medical records of all patients with acute ischemic stroke who underwent ultrasonic examination after intravenous thrombolysis between April 2017 and December 2019 at the stroke center of the First Hospital of Jilin University, China. Color duplex ultrasound was used to diagnosis DVT in all patients within 72 h after intravenous thrombolysis. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for DVT. Results: Overall, 474 patients were included in the study. Of these, 75 (15.8%) developed DVT (95% confidence interval 12.5– 19.1). Older age was the risk factor that most significantly affected the development of DVT (p = 0.001). Compared to patients younger than 60 years old, those aged 60– 69 years and ≥ 70 years had a higher risk of DVT, at rates of 2.201 (95% CI: 1.033– 4.689; p < 0.05) and 4.241 (95% CI: 2.016– 8.922; p < 0.001) times higher, respectively. Patients with higher triglyceride levels (odds ratio 0.545, 95% CI: 0.372– 0.799, p = 0.002) and longer activated partial thromboplastin time (OR 0.927, 95% CI: 0.862– 0.996, p = 0.040) were less likely to have DVT. Conclusion: DVT is a common complication among patients undergoing intravenous thrombolysis after acute ischemic stroke. Advanced age may increase the occurrence of DVT to some extent. For these patients, safe antiplatelet therapy should be explored and implemented as soon as possible. [ABSTRACT FROM AUTHOR]

Objective. Hematoma expansion is closely associated with adverse functional outcomes in patients with intracerebral hemorrhage (ICH). Prediction of hematoma expansion would therefore be of great clinical significance. We therefore attempted to predict hematoma expansion using a dual-modal machine learning (ML) strategy which combines information from non-contrast computed tomography (NCCT) images and multiple clinical variables. Approach. We retrospectively identified 140 ICH patients (57 with hematoma expansion) with 5616 NCCT images of hematoma (2635 with hematoma expansion) and 10 clinical variables. The dual-modal ML strategy consists of two steps. The first step is to derive a mono-modal predictor from a deep convolutional neural network using solely NCCT images. The second step is to achieve a dual-modal predictor by combining the mono-modal predictor with 10 clinical variables to predict hematoma growth using a multi-layer perception network. Main results. For the mono-modal predictor, the best performance was merely 69.5% in accuracy with solely the NCCT images, whereas the dual-modal predictor could boost the accuracy greatly to be 86.5% by combining clinical variables. Significance. To our knowledge, this is the best performance from using ML to predict hematoma expansion. It could be potentially useful as a screening tool for high-risk patients with ICH, though further clinical tests would be necessary to show its performance on a larger cohort of patients. [ABSTRACT FROM AUTHOR]

The double flower is a highly important breeding trait that affects the ornamental value in many flowering plants. To get a better understanding of the genetic mechanism of double flower formation in Dianthus chinensis , we have constructed a high-density genetic map using 140 F2 progenies derived from a cross between a single flower genotype and a double flower genotype. The linkage map was constructed using double-digest restriction site-associated DNA sequencing (ddRAD-seq) with 2353 single nucleotide polymorphisms (SNPs). Quantitative trait locus (QTL) mapping analysis was conducted for 12 horticultural traits, and major QTLs were identified for nine of the 12 traits. Among them, two major QTLs accounted for 20.7% and 78.1% of the total petal number variation, respectively. Bulked segregant RNA-seq (BSR-seq) was performed to search accurately for candidate genes associated with the double flower trait. Integrative analysis of QTL mapping and BSR-seq analysis using the reference genome of Dianthus caryophyllus suggested that an SNP mutation in the miR172 cleavage site of the A-class flower organ identity gene APETALA2 (DcAP2L) is responsible for double flower formation in Dianthus through regulating the expression of DcAG genes. [ABSTRACT FROM AUTHOR]

Background: From 2017, the Stroke Health Manager Training Project was carried out by the Chinese Government to strengthen health management and follow-up intervention after ischemic stroke. The aim of this study was to investigate whether after the intervention of the stroke health manager, the control of blood pressure, low-density lipoprotein cholesterol (LDL-C), glucose level, and the use of secondary prevention medications improved 3 months after discharge from our center following ischemic stroke. Methods: The study used a history-controlled approach. Patients who received stroke health manager intervention from May 1, 2018, to March 31, 2019, were considered as the intervention group; those from May 1, 2017, to April 30, 2018, were enrolled as the control group. Stroke health manager intervention included health education, discharge advice, online WeChat public group follow-up, and clinical consultation. Results: In total, 642 patients with ischemic stroke were enrolled in this study (277 in the control group, 365 in the intervention group). At 3 months, the blood pressure, LDL-C and glucose control in the intervention group were better than in the control group (all P < 0.05). At the same time, the overall persistence for secondary prevention medications at 3 months after discharge increased from 201/277 (72.56%) to 303/365 (83.01%, P = 0.001). The persistence for patients taking antiplatelet, hypoglycemic and statins were significantly higher in the intervention group (P < 0.05). Conclusions: Stroke health manager intervention improved the control of blood pressure, LDL-C, glucose levels and the persistence for secondary prevention medications 3 months after discharge. [ABSTRACT FROM AUTHOR]

Estuaries sit at the land‐ocean boundary and act as natural reactors for nitrogen (N) transformations among numerous forms. Superimposing onto physical mixing, biological processes lead to nonconservative N behavior in estuaries. Under the coinfluences of biological alteration and multiple end‐members, however, some N species can exhibit apparent conservation. To explore N dynamics and potential mechanisms that modulate the mixing behaviors, we measured concentrations and natural isotopic compositions of multiple N species (nitrate: NO3−, nitrite: NO2−, ammonium: NH4+, and particulate nitrogen) in a typical eutrophic estuary in southern China. Additionally, N uptake and oxidation rates were measured by using isotope labelling techniques to evaluate processes potentially offsetting the conservative mixing of specific N pools. We found that NO3− followed conservative two end‐member mixing with dual isotopes varying in a narrow range (<1–2‰) due to low microbial preferences. Moreover, δ15N‐NO2− revealed a nonconservative pattern with an involvement of multiple end‐members. The dominant N transformation processes shifted downstream. In the upper estuary, ammonia oxidation (~20 μmol L−1 day−1) dominated NH4+ removal and was accompanied by NO2− accumulation. In the middle‐lower estuary, NH4+ uptake became dominant, with phytoplankton showing strong preference for it over NO3− and NO2−. Based on measured NH4+ uptake rates (9.1–12.5 μmol L−1 day−1 in the light and 0.9 μmol L−1 day−1 in the dark), short water residence time (<1 day) was required to maintain the conservative mixing. Coupling N isotopes in multiple nitrogen species with measurements of N uptake and nitrification, we successfully uncovered N dynamics and distinguished biological processes from physical mixing. Key Points: Phytoplankton much prefer ammonium over nitrate and nitrite in eutrophic estuaryOxidation of ammonia was significantly higher than nitrite in turbid waterδ15N‐NO2– nicely reveals multiple nitrogen end‐members [ABSTRACT FROM AUTHOR]

A detailed reaction mechanism of the hydrogenation of quinoline to 1,2,3,4-tetrahydroquinoline catalysed by a half-sandwich Cp*Ir triazolylidene complex was computationally investigated by using density functional theory. The direct proton transfer from Ir to the nitrogen atom in quinoline was found to be the rate-determining step with a total barrier of 25.1 kcal mol−1 in free energy. Furthermore, by replacing the hydrogen atoms at the para (R) positions of the pyridine ligand with different functional groups, and the triazolylidene ligands with various N-heterocyclic carbenes, we proposed a series of half-sandwich Ir, Rh, and Co complexes and computationally screened four promising candidates for the catalytic hydrogenation of quinoline to 1,2,3,4-tetrahydroquinoline with predicted total free energy barriers close to 24.0 kcal mol−1. [ABSTRACT FROM AUTHOR]

Aims: To report experience of perioperative nursing of tracheal silicon stent implantation in infants. Methods: Retrospective analysis on the cases of tracheal silicon stent implantation in infants in our hospital. Results and Conclusions: Since middle of 2014, totally four tracheal silicon stent implantation were performed in our center. Of them, one case was recurrent tracheoesophageal fistula and the other three cases were traheomalacia. Parent’s psychological support, infants’ nutrition support and airway care were key responsibility for a nurse before implantation. During the procedure of stent implantation, it was responsible for a nurse to closely monitor the infants and to support operator. After the implantation, airway care and prevention of intra-airway bacterial colonization were important to avoid complications. [ABSTRACT FROM AUTHOR]

Background and purpose: Intravenous thrombolytic therapy significantly improves the outcomes of acute ischemic stroke patients in a time-dependent manner. The aim of this study was to investigate whether continuous nursing quality improvement in stroke nurses has a positive effect on reducing the time to thrombolysis in acute ischemic stroke. Methods: The implementation of nursing quality improvement measures includes establishing full-time stroke nurses, pre-notification by emergency medical services (EMS), stroke team notification protocols, rapid triage, publicity and education, etc. Using a history-controlled approach, we analyzed acute ischemic stroke patients with intravenous thrombolysis during a pre-intervention period (April 1, 2015-July 31, 2016), trial period (August 1, 2016-October 31, 2016), and post-intervention period (November 1, 2016-September 30, 2017). This was done in accordance with the implementation of nursing quality improvement measures, including the general characteristics of the three groups, the time of each step in the process of thrombolysis, and the prognosis. Results: After the implementation of nursing quality improvement measures, the median door-to-needle time (DNT) was shortened from 73 min (interquartile range [IQR] 62–92 min) to 49 min (IQR 40-54 min; p < 0.001) in the post-intervention period. The median onset-to-needle time (ONT) was reduced from 193 min (IQR 155–240 min) to 167 min (IQR 125-227 min; p < 0.001). The proportion of patients with DNT ≤ 60 min increased from 23.94% (51/213) to 86.36% (190/220; p < 0.001) while the proportion of patients with DNT ≤ 40 min increased from 3.29% (7/213) to 25.00% (55/220; p < 0.001). The median time for door-to-laboratory results was decreased from 68 min to 56 min (p < 0.001). There was no significant difference in the fatality rate, 90-day modified Rankin score, length of stay or hospitalization expenses between the three groups of patients (p > 0.05). Conclusions: Implementation of nursing quality improvement measures in stroke nurses is an important factor in shortening the time of medication in patients with thrombolytic therapy, reducing the delay of intravenous thrombolysis in the hospital and helping to expedite presenting patients' arrival to the hospital post-stroke. [ABSTRACT FROM AUTHOR]

Background and Purpose: Dynamic cerebral autoregulation (dCA) is probably impaired in the acute and even subacute phases after acute ischemic stroke (AIS); however, the relationship between relevant clinical factors and dCA after AIS has not been investigated. The identification of possible determinants may therefore provide potential therapeutic targets to improve dCA in AIS. Methods: This study enrolled 67 consecutive patients diagnosed with AIS within 3 days from symptom onset. Serial measurements were performed 1–3 days (measurement 1) and 7–10 days (measurement 2) after the onset. Middle cerebral artery blood flow velocities and simultaneous arterial blood pressure (ABP) were recorded continuously with transcranial Doppler combined with a servo-controlled finger plethysmograph. Transfer function analysis was used to derive dCA parameters, phase difference (PD), and coherence in low-frequency range (0.06–0.12 Hz). Univariate and multivariate linear regression analyses were conducted to determine the relationship between clinical factors and PD within the two time points of measurements. Multivariate logistic regression was performed to reveal the relationship between PD and clinical outcomes. Results: Bilateral PD was significantly lower (indicating impaired dCA) in AIS patients, both in measurement 1 and measurement 2 when compared with those of healthy controls (all P < 0.001). After controlling for relevant clinical factors, in measurement 1, age (β = −0.29, P = 0.01), recombinant tissue plasminogen activator (rt-PA) intravenous thrombolysis (β = 0.25, P = 0.034), subtype of large-artery atherosclerosis (LAA) (β = −0.31, P = 0.007), and uric acid level (β = −0.32, P = 0.009) were significant independent predictors of ipsilateral PD. In measurement 2, subtype of LAA (β = −0.28, P = 0.049) and uric acid level (β = −0.43, P = 0.005) were still significant predictive values for ipsilateral PD. After adjusting for age and National Institutes of Health Stroke Scale at admission, ipsilateral PD >35.37° in measurement 2 was independent predictor of good clinical outcomes (adjusted OR = 6.97, 95% CI: 1.27–38.14, P = 0.03). Conclusion: DCA was sustained to be bilaterally impaired in the acute and even subacute phase after AIS. Patients who receiving rt-PA thrombolysis tended to have a better dCA in the acute phase. Increasing age, subtype of LAA, and higher uric acid level had prognostic value for disturbed autoregulation. A relatively preserved dCA may predict good clinical outcomes. [ABSTRACT FROM AUTHOR]

Density functional theory study of the hydrogenation of ethyl acetate catalysed by iridium complexes [Cp*Ir(bpy)OH2]2+ reveals a direct C–O bond cleavage mechanism with two cascade catalytic cycles for the hydrogenation of ethyl acetate to aldehyde and the hydrogenation of aldehyde to ethanol. Calculation results indicate that the rate-determining state in the whole catalytic reaction is the direct C–O bond cleavage for the formation of aldehyde and ethanol with a total free energy barrier of 25.5 kcal mol−1, which is 0.6 kcal mol−1 more favorable than the mechanism proposed by Goldberg and co-workers in their experimental study. [ABSTRACT FROM AUTHOR]

The influence of the anterior and posterior communicating artery (ACoA and PCoA) on dynamic cerebral autoregulation (dCA) is largely unknown. In this study, we aimed to test whether substantial differences in collateral anatomy were associated with differences in dCA in two common types of stenosis according to digital subtraction angiography (DSA): either isolated basal artery and/or bilateral vertebral arteries severe stenosis/occlusion (group 1; group 1A: with bilateral PCoAs; and group 1B: without bilateral PCoAs), or isolated unilateral internal carotid artery severe stenosis/occlusion (group 2; group 2A: without ACoA and with PCoA; group 2B: with ACoA and without PCoAs; and group 2C: without both ACoA and PCoA). The dCA was calculated by transfer function analysis (a mathematical model), and was evaluated in middle cerebral artery (MCA) and/or posterior cerebral artery (PCA). Of a total of 231 non-acute phase ischemic stroke patients who received both dCA assessment and DSA in our lab between 2014 and 2017, 51 patients met inclusion criteria based on the presence or absence of ACoA or PCoA, including 21 patients in the group 1, and 30 patients in the group 2. There were no significant differences in gender, age, and mean blood pressure between group 1A and group 1B, and among group 2A, group 2B, and group 2C. In group 1, the PCA phase difference values (autoregulatory parameter) were significantly higher in the subgroup with patent PCoAs, compared to those without. In group 2, the MCA phase difference values were higher in the subgroup with patent ACoA, compared to those without. This pilot study found that the cross-flow of the ACoA/PCoA to the affected area compensates for compromised dCA in the affected area, which suggests an important role of the ACoA/PCoA in stabilizing cerebral blood flow. [ABSTRACT FROM AUTHOR]

Abstract: Riverine nitrogen input into the coastal zone has increased remarkably in recent decades. Yet its transformation and recycling within hydrodynamically active regions remains unclear. Using observations of nitrate concentration and dual isotopic composition across the Changjiang River plume within a three end‐member mixing model, we found deviations between the observed and expected values for mixing alone, revealing the nonconservative behavior of nitrate. Using cross correlations between concentrations and dual isotope deviations, we identified three nitrogen transformation zones, which correspond to separate portions of the plume. Nitrification and sedimentary denitrification occurred near the river mouth, nitrification prevailed further offshore under the plume, and finally, phytoplankton assimilation occurred in the outer surface plume (>100 km offshore), where it was fueled by nitrate that had already been strongly modified by microbial processes. Information was assembled into a conceptual model offering an overview of nitrogen transformations in a large river plume. [ABSTRACT FROM AUTHOR]

Nitrogen sources and dynamics, one of the key issues in marine biogeochemical cycles, remain poorly constrained in marginal seas. Here we examine the nitrogen cycle in the northern South China Sea (SCS) by combining data from previous reports with a new data set of N isotopic compositions (δ15N) of nitrate, zooplankton, and sinking particles. Average δ15N in subsurface nitrate is 4.8 ± 0.3‰, similar to that of sinking particles (δ15Nsink of 4.4‰) through the euphotic zone (EZ) collected by floating traps and to documented mean (4.6‰) for long-term mooring traps at 200 m. This along with oft-observed shallow nitracline (<100 m) suggests that subsurface nitrate is the primary source of new N to support export production. Moreover, δ15Nsink at the bottom of the EZ resembles those of suspended particles (4.2 ± 1.0‰) and zooplankton (5.4 ± 1.0‰) inside the EZ. High similarity in δ15N among various types of particles including zooplankton in different size fractions in the EZ implies rapid N turnover in the ecosystem. In deep waters at 2000-3000 m, however, additional particulate N fluxes are found due to lateral transport, which contain 15N-depleted particles, resulting in a downward decreasing trend of δ15Nsink. Incorporation of lighter N by bacteria and selective export of picoplankton are proposed as alternative mechanisms contributing to low δ15Nsink in the deep waters. The significant δ15Nsink change in the deep water column makes the SCS different from most other marginal seas; thus, caution should be made when using sedimentary δ15N to reconstruct paleonitrogen processes. [ABSTRACT FROM AUTHOR]

Background and Aim. MicroRNAs (miRNAs) have been implicated in the pathophysiology of numerous human diseases including gastroesophageal reflux disease (GERD). The objective of this study was to investigate the miRNA expression of exfoliated cells of the tongue in patients with GERD versus healthy controls (Ctrls). Methods. Using quantitative reverse-transcription PCR (qRT-PCR), expression levels of six candidate miRNAs (miR-143, miR-145, miR-192, miR-194, miR-203, and miR-205) were examined across a discovery cohort of patients with GERD (n=24) versus Ctrls (n=24). These findings were confirmed across a validation cohort (GERD, n=142; Ctrls, n=48). Differences in miRNA expression levels were evaluated using the Mann-Whitney U test while the specificity and sensitivity were obtained using receiver-operator characteristic (ROC) curves. Results. miR-203 was significantly downregulated in GERD patients as compared to Ctrls (P<0.0001) with ROC curve of 0.94 (95% CI: 0.90–0.97). The sensitivity and the specificity of miR-203 were 91.7% and 87.3%, respectively, in the GERD and Ctrls. These results suggest that miR-203 may be a useful diagnostic marker for discriminating GERD from Ctrls. Conclusions. miR-203 testing may assist in the diagnosis of patients with symptoms suggestive of GERD. [ABSTRACT FROM AUTHOR]

The metal–metal and metal–ligand bonds in the bimetallic sandwich compounds Pn*2M2 (Pn* = C8Me6; M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) have been investigated using the atoms in molecules (AIM) theory, electron location function (ELF), and electron decomposition analysis (EDA). The calculated results indicate that the strength of the metal–metal (M–M) bond and the coordination mode of the Pn* ligands to a pair of metal atoms depend on the d electron configuration of the transition metal. The more unpaired d electrons, the higher the coordination number of the metal to the ligands, which increases from η1 to η5. The stronger the metal–ligand interaction, the weaker the contribution of the electrostatic interaction to the metal–ligand interaction. The strength of the M–M bonds increases in the sequence M = Sc ＜ Ti ＜ V, and decreases in the sequence V ＞ Cr ＞ Mn ＞ Fe ＞ Co ＞ Ni ＞ Cu. The V–V bond is the strongest of the studied dinuclear first-row transition metal–(C8Me6)2 complexes. The studied M–M bonds are metallic bonds and have a partially covalent character, except for Sc–Sc which is a covalent bond and Cu–Cu which is an electrostatic interaction. [ABSTRACT FROM AUTHOR]