Evaluating methods for marine fuel sulfur content using microsensor sniffing systems on ocean-going vessels.

Establishing emission control areas (ECAs) can effectively reduce air pollution from marine emissions, making efficient monitoring of the fuel sulfur content (FSC) of ocean-going vessels (OGVs) key to ECA policy enforcement. Various FSC detection approaches, including oil sample analysis, sniffing method, and optical remote sensing, have been proposed, each with its benefits and drawbacks. Among these, the sniffing method appears promising but requires further improvement in field operation protocol and data analysis processes. This study aims to develop a comprehensive methodology, including sensor calibration, field operations, and data analysis, to enhance the performance of an Unmanned Aerial Vehicle (UAV)-based Microsensor Sniffing System (MSS) for real-time FSC monitoring. Hong Kong has a cap of 0.5 % m/m FSC for OGVs, and hence Hong Kong waters served as the "real-world" monitoring location to evaluate the MSS system through land-based and sea-based measurements. Three different FSC calculation methods were employed and verified against bunker delivery note (BDN) data through blind testing. Results confirm that the MSS is effective in field settings, though it has an underestimation tendency, demonstrating an absolute error of 0.06 % m/m, 0.11 % m/m, and 0.10 % m/m for the Crest, Slope, and Area methods, respectively, compared to BDN data. However, high errors were possible with low CO2 and SO2 peak heights, and single-peak samples compared to multi-peak samples. Over 16 successful trips, the FSC of 125 valid OGVs (Mean FSC = 0.39 % m/m) exhibited a lognormal distribution pattern, with the distribution tail approaching the 0.5 % m/m regulatory cap. This investigation highlights the potential of a UAV-based MSS for monitoring and enforcing FSC regulations within ECAs, providing a systematic protocol to guide future research direction and enforcement practices.

Transcriptomics explores the potential of flavonoid in non-medicinal parts of Saposhnikovia divaricata (Turcz.) Schischk.

Introduction: Saposhnikovia divaricata is a traditional Chinese medicine in China, which is widely used in clinic. The root of S. divaricata is often used as medicine, but little research has been done on its other tissues. Methods: In this study, the contents of root and leaf of S. divaricata were determined by HPLC, the differentially expressed genes were screened by transcriptome sequencing at molecular level, and then verified by network pharmacology. Results: The results showed that the content of 4'-O-ß-D-glucosyl-5-O-methylvisamminol in the leaves was significantly higher than that in the roots, which was about 3 times higher than that in the roots. In addition, 10 differentially expressed key enzyme genes were screened in plant hormone signal transduction, phenylpropanoid and flavonoid biosynthetic pathways. C4H and CYP98A were up-regulated in root, while F3H was down-regulated in root. They can be used as important candidate genes for the mechanism of quality difference of S. divaricata. Finally, network pharmacological validation showed that 5-O-methylvesamitol plays an important role in the treatment of ulcerative colitis. Discussion: These findings not only provide insight into flavonoid biosynthesis in S. divaricata associated molecular regulation, but also provide a theoretical basis for the development and utilization of S. divaricata.

Manufacturing process of short carbon fiber reinforced Al matrix with preformless and their properties.

The conventional manufacturing process of fiber-reinforced metal matrix composites via liquid infiltration processes, preform manufacturing using inorganic binders is essential. However, the procedure involves binder sintering, which requires high energy and long operating times. A new fabrication process without preform manufacturing is proposed to fabricate short carbon fiber (SCF)-reinforced aluminum matrix composites using a low-pressure infiltration method. To improve the wettability between fiber and matrix, fibers were plated copper using an electroless plating process. The low-pressure infiltration method with preformless succeeded in manufacturing a composite with a volume fraction of about 30% of carbon fibers.The fiber orientation of the composite material manufactured without preform and the fiber orientation of the composite material manufactured using an inorganic binder was almost the same. The manufactured composites with preformless have high hardness and high thermal conductivity.

Ureteral reconstruction with decellularized small intestinal submucosa matrix for ureteral stricture: A preliminary report of two cases.

OBJECTIVE: To determine the feasibility of decellularized small intestinal submucosa (SIS) matrix in repairing ureteral strictures. METHODS: Two patients with ureteral stenoses underwent ureteral reconstruction with SIS matrix at the Zhejiang Provincial Corps Hospital of Chinese People's Armed Forces between June 2014 and June 2016. The ureteral stenoses were repaired with a semi-tubular SIS matrix and the postoperative recoveries were observed. RESULTS: Both operations were successfully completed. The average operative time was 90 min and the average length of hospital stay was 15 days. No fevers, incision infections, intestinal obstruction, graft rejection, or other serious complications were noted. After 2 months, ureteroscopic examinations showed that the surfaces of the original patches were covered by mucosa and there were no apparent stenoses in the lumens. The ureteral stents were replaced every 2 months postoperatively and removed 12 months postoperatively. No infections or urinary leakage occurred after removal of the stents. Intravenous urography was performed 6 and 12 months postoperatively. The results showed that the ureters were not obstructed and there was no apparent stenosis at the anastomosis sites. The average follow-up time was >12 months. Long-term follow-up is still ongoing, and computed tomography examinations of the urinary tract have been conducted in the outpatient department of our hospital 1, 3, and 6 months after removal of the double-J stents, suggesting the absence of hydronephrosis. The serum creatinine levels remained stable during the follow-up. CONCLUSION: SIS matrix reconstruction is a feasible method to repair ureters stenosis.

Emission characteristics of fine particulate matter from ultra-low emission power plants.

As one of the highest energy consuming and polluting industries, the power generation industry is an important source of particulate matter emissions. Recently, implementation of ultra-low emission technology has changed the emission characteristic of fine particulate matter (PM2.5). In this study, PM2.5 emitted from four typical power plants in China was sampled using a dilution channel sampling system, and analyzed for elements, water-soluble ions and carbonaceous fractions. The results showed that PM2.5 concentrations emitted from the four power plants were 0.78 ±â€¯0.16, 0.63 ±â€¯0.09, 0.29 ±â€¯0.07 and 0.28 ±â€¯0.01 mg m-3, respectively. Emission factors were 0.004-0.005 g/kg coal, nearly 1-2 orders of magnitude lower than those reported in previous studies. The highest proportions of PM2.5 consisted of organic carbon (OC), SO42-, elemental carbon (EC), NH4+, Al and Cl-. Coefficients of divergence (CDs) were in the ranges 0.22-0.41 (for an individual plant), 0.43-0.69 (among different plants), and 0.60-0.99 (in previous studies). The results indicated that the source profiles of each tested power plant were relatively similar, but differed from those in previous studies. Enrichment factors showed elevated Se and Hg, in accordance with the source markers Se and As. Comparing source profiles with previous studies, the proportion of OC, EC and NH4+ were higher, while the proportion of Al in PM2.5 were relatively lower. The OC/EC ratio became concentrated at ∼5. Results from this study can be used for source apportionment and emission inventory calculations after implementation of ultra-low emission technologies.

Triel bonds in RZH2···NH3: hybridization, solvation, and substitution.

The influence of hybridization, substitution, and solvation on the triel bond has been investigated in the complexes of RZH2···NH3 (Z = B and Al). The magnitude of the π-hole on the triel atom is related to the nature of the Z atom and the hybridization of R. CH3BH2 has the largest π-hole among RBH2, while for RAlH2 the largest π-hole is found in CH≡CAlH2. The interaction energy is partly inconsistent with the magnitude of the π-hole on the triel atom and the orbital interaction from the N lone pair of NH3 into the empty p orbital of the triel atom. The strongest B···N triel bond is found in CH≡CBH2···NH3, while the weakest Al···N triel bond is in CH3AlH2···NH3. The strength of the triel bond is increased in solvents, and its enhancement is prominent with the increase of solvent polarity. Solvents also change the nature of the Al···N triel bond from an electrostatic interaction to a partially covalent one. The F substituent in the triel donor strengthens the triel bond, depending on the substitution position and number. Graphical Abstract The π-hole triel bonded complexes between RZH2 (Z =B and Al) and NH3 have been investigated. We focused on the effects of hybridization, solvent, and substitution on the strength and nature of π-hole triel bond.

A high temporal-spatial emission inventory and updated emission factors for coal-fired power plants in Shanghai, China.

With the implementation of the ultra-low emission policy in China, emission factors (EFs) of power plant pollutants are constantly changing. Emission inventories developed using the recommended EFs contain high levels of uncertainty and it is difficult to achieve a high temporal resolution. Detailed sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter (PM) emission data based on a continuous emission monitoring system (CEMS) were obtained from 33 units at 13 power plants in Shanghai in 2017. The data were used to develop an hourly unit-based emission inventory and to devise updated EFs for coal-fired power plants. Emissions of SO2, NOx, and PM typically met the ultra-low emission limit, with total emissions of SO2, NOx, and PM of 2895.0, 5348.3, and 503.8 tons, respectively. Emission proportions of SO2 and NOx for 300-600, 600-1000, and above 1000 MW units were similar, while the emission proportion of PM decreased with an increase in unit capacity. Emissions of SO2, NOx, and PM displayed similar monthly variations, peaking in winter and summer. Diurnal hourly variations of SO2, NOx, and PM emissions displayed a bimodal trend, with higher emissions at night on weekends than on weekdays. EFs based on CEMS (EFC) of SO2, NOx, and PM were 0.10, 0.36, and 0.04 g kg-1 of coal, respectively, which were one or two orders of magnitude lower than the widely-used EFs and 4-30 times lower than EFs based on the mass balance approach. After replacing the recommended fixed decontamination efficiencies with individually fitted values, the calculated EFs were consistent with the corresponding EFC and discrepancies were further reduced. The new inventory and updated EFs will enable a better understanding of the temporal variations of power plant emissions and reduce the uncertainty caused by the overestimation of EFs after the implementation of ultra-low emissions technology.

Competition between tetrel bond and pnicogen bond in complexes of TX3-ZX2 and NH3.

The complexes formed between TX3-ZX2 (T = C, Si, Ge; Z = P, As, Sb; X = F, Cl) and NH3 were studied at the MP2/aug-cc-pVTZ(PP) level. For each TX3-ZX2, two types of complex were obtained. For CX3-ZX2, NH3 is inclined to approach the σ-hole on the Z atom, forming a pnicogen bond. For TX3-ZX2 (T = Si and Ge), however, the base favors engaging in a tetrel bond with the σ-hole on the T atom although the corresponding pnicogen-bonded complex is also stable. When NH3 approaches the CX3 terminal of CX3-ZX2, weak interactions are observed that may be classified as van der Waals interactions. The relative stability of both types of complexes is not affected by the substituent X. The tetrel bond is very strong and the largest interaction energy is up to -144 kJ mol-1. Dispersion is dominant in the weak van der Waals complexes, while tetrel- and pnicogen-bonded complexes are dominated by electrostatic interactions, with comparable contributions from polarization.

Rapid oriented fibril formation of fish scale collagen facilitates early osteoblastic differentiation of human mesenchymal stem cells.

We studied the effect of fibril formation of fish scale collagen on the osteoblastic differentiation of human mesenchymal stem cells (hMSCs). We found that hMSCs adhered easily to tilapia scale collagen, which remarkably accelerated the early stage of osteoblastic differentiation in hMSCs during in vitro cell culture. Osteoblastic markers such as ALP activity, osteopontin, and bone morphogenetic protein 2 were markedly upregulated when the hMSCs were cultured on a tilapia collagen surface, especially in the early osteoblastic differentiation stage. We hypothesized that this phenomenon occurs due to specific fibril formation of tilapia collagen. Thus, we examined the time course of collagen fibril formation using high-speed atomic force microscopy. Moreover, to elucidate the effect of the orientation of fibril formation on the differentiation of hMSCs, we measured ALP activity of hMSCs cultured on two types of tilapia scale collagen membranes with different degrees of fibril formation. The ALP activity in hMSCs cultured on a fibrous collagen membrane was significantly higher than on a non-fibrous collagen membrane even before adding osteoblastic differentiation medium. These results showed that the degree of the fibril formation of tilapia collagen was essential for the osteoblastic differentiation of hMSCs.

Synthesis of luminescent nanoporous silica spheres functionalized with folic acid for targeting to cancer cells.

Luminescent europium(III)-doped nanoporous silica nanospheres (Eu:NPS) were successfully synthesized, and a folate N-hydroxysuccinimidyl ester (FA-NHS) molecule as a targeting ligand for cancer cells was immobilized on the nanosphere surfaces through mediation of the 3-aminopropyltriethoxysilane (APTES) adlayer. The ordered nanopores were preserved by the immobilization, and the specific surface area decreased only with the APTES immobilization, suggesting that the FA-NHS was predominantly immobilized on the outer surface of the nanopores. The photoluminescence of the nanospheres functionalized with folic acid (FA) exhibited a characteristic peak due to the interactions (e.g., energy transfer) between FA and Eu(3+), and further the orange luminescence could be clearly detected by fluorescence microscopy in air and water. Furthermore, the nanospheres highly dispersed in cell culture medium exhibited nontoxicity in the cellular proliferation stages of the Hela cancer cells and NIH3T3 fibroblasts and specifically bind to the Hela cells. The nanospheres after the binding and uptake also showed intense luminescence from the outer/inner cell surfaces for the culture time of 4 days. Therefore, the luminescent FA-functionalized Eu:NPS nanospheres could be used for specific targeting and imaging abilities for cancer cells.

Synthesis and luminescence properties of Eu(III)-doped nanoporous silica spheres.

Europium (III) (Eu(3+))-doped nanoporous silica spheres were synthesized, and the states of Eu(3+) ions in the silica framework structure were investigated. The ordered nanopores were preserved with the doping at the Eu(3+) molar concentration to Si up to 10 mol%, and the O-Si-O and Si-OH groups in the structures were clearly rearranged with the doping, indicating the interaction of Eu(3+) with the O atoms. The significant morphological changes in the spheres were observed with the doping. The photoluminescence spectral shapes due to the transitions of (5)D(0)-(7)F(1) and (5)D(0)-(7)F(2) were indicative of the presence of the Eu(3+) in an environment of a low symmetry. It was found that the Eu(3+) was located inside the silica framework to electrostatically interact with the environmental O atoms, which would prevent the aggregation among Eu(3+) ions to show the efficient luminescence. Therefore, the interactions between the Eu(3+) ions and silica framework structures in the spheres were successfully clarified.

Immobilization of folic acid on Eu3+-doped nanoporous silica spheres.

Folic acid (FA) was immobilized on Eu(3+)-doped nanoporous silica spheres (Eu:NPSs) through mediation of the 3-aminopropyltriethoxysilane adlayer. The ordered nanopores of Eu:NPS were preserved by the immobilization. The FA-immobilized Eu:NPSs showed the characteristic photoluminescence peak due to interactions between the FA molecules and Eu(3+) ions, and highly dispersed stability in phosphate buffered saline.

Psychometric evaluation of the Chinese (mainland) version of Job Content Questionnaire: a study in university hospitals.

To evaluate the psychometric properties of the Chinese (mainland) version of Job Content Questionnaire (JCQ), this validation study was conducted in university hospitals among 193 men and 581 women health care workers. The Cronbach's alpha coefficients for decision latitude, psychological job demands and social support ranged from 0.56 to 0.82, which indicated that psychological job demands had lower internal consistency. The decision latitude displayed a negative correlation with psychological job demands and a positive correlation with social support. Exploratory factor analysis showed 3 meaningful factors that could explain the 3 theoretical dimensions of job strain model. Apart from some uncertainty over psychological job demands particularly, it is concluded that the Chinese (mainland) version of JCQ is a reliable and valid instrument for measuring job stressors, and is applicable to Chinese working population.