AbstractTo ensure the safety of adjacent 16.7-m-high concrete frame structures (cooling towers) and buried pipelines in service during installation of 83 prestressed high-strength concrete (PHC) pipe ...piles, the behavior of the ground, the buried pipelines, and cooling towers was monitored by a comprehensive instrumentation program. The field measurements included the following: (1) time histories of the particle velocities and corresponding Fourier spectra in three mutually perpendicular directions at various pile penetration depths and (2) vertical and horizontal movements of the buried pipelines caused by pile installation. Based on the analysis of the field data, the following major findings were obtained: (1) unlike the driving of prestressed concrete piles or cast in situ piles, the vibration velocity in the vertical direction was not greater than that in the plane during PHC pipe pile driving; (2) the amplitudes of the peak particle velocities were relatively independent of the pile penetration depths because of the complex soil conditions; (3) both the ground and the concrete structure experienced primarily high-frequency vibrations, which attenuated rapidly over time; (4) during the pile driving, only slight vibration amplification was observed at the upper levels of the existing concrete frame structure as a result of the soil-structure interaction—the concrete structure had a much wider frequency band (around 0–300 Hz) than the ground (around 0–100 Hz); and (5) the method of installing the piles close to the existing facilities before installing those a distance away effectively mitigated the potential adverse effects on the buried pipelines.
Celotno besedilo
Dostopno za:
DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
As rate-limiting enzymes of β-oxidation of fatty acids in mitochondria, the carnitine palmitoyltransferase (CPT) played an important role in regulating energy homeostasis of aquatic animals. However, ...there was very little research on β-oxidation of fatty acids in crustaceans. In the present study, the full-length cDNA sequences of
cpt-1a
,
cpt-1b
and
cpt-2
were isolated from the hepatopancreas of
Scylla paramamosain
, and contained 4206, 5303 and 3486 bp respectively. Sequence analysis showed that the CPT-1A, CPT-1B and CPT-2 encoded proteins with 777, 775 and 672 amino acids respectively, and only the CPT-1A possessed a transmembrane region. In addition, both the CPT-1B and CPT-2 contained conservative functional domains like N-terminal domain and acyltransferases choActase 2, while the CPT-1A lacked. The results of phylogenetic tree indicated that the CPT-1A, CPT-1B and CPT-2 of
S. paramamosain
gathered together with their corresponding orthologues from crustaceans. The tissue distribution exhibited that the
cpt-1a
was highly expressed in hepatopancreas, followed by muscle, eyestalk and cranial ganglia, and the muscle, eyestalk and heart were main expressed tissues of
cpt-1b
. Furthermore, the high expression levels of
cpt-2
were mainly detected in hepatopancreas, muscle and heart. The transcriptional levels of
cpt-1a
,
cpt-1b
and
cpt-2
were significantly up-regulated under chronic low salinity stress. Besides, at the acute low salinity stress condition, the expression levels of
cpt-1a
,
cpt-1b
and
cpt-2
in hepatopancreas were dramatically increased in 14‰ and 4‰ salinity groups at the 6h and 48h, while the transcriptional levels of
cpt-1a
,
cpt-1b
and
cpt-2
in muscle were signally up-regulated in 14‰ and 4‰ salinity groups at the 12h and 24h, showing an alternate response pattern. Similarly, the present study found that fasting could markedly increase the expression levels of
cpt-1a
,
cpt-1b
and
cpt-2
in hepatopancreas and muscle, especially
cpt-1a
in hepatopancreas as well as
cpt-1a
and
cpt-1b
in muscle. The results above indicated that the
cpt-1a
,
cpt-1b
and
cpt-2
played a crucial part in providing energy for coping with fasting and salinity stress. These results would contribute to enhancing the knowledge of
cpt
phylogenetic evolution and their roles in energy metabolism of crustaceans.
Here, we report the successful design of a novel bacteria-selective antimicrobial peptide, Pep-1-K (KKTWWKTWWTKWSQPKKKRKV). Pep-1-K was designed by replacing Glu-2, Glu-6, and Glu-11 in the ...cell-penetrating peptide Pep-1 with Lys. Pep-1-K showed strong antibacterial activity against reference strains (MIC=1–2μM) of Gram-positive and Gram-negative bacteria as well as against clinical isolates (MIC=1–8μM) of methicillin-resistant Staphylococcus aureus and multidrug-resistant Pseudomonas aeruginosa. In contrast, Pep-1-K did not cause hemolysis of human erythrocytes even at 200μM. These results indicate that Pep-1-K may be a good candidate for antimicrobial drug development, especially as a topical agent against antibiotic-resistant microorganisms. Tryptophan fluorescence studies indicated that the lack of hemolytic activity of Pep-1-K correlated with its weak ability to penetrate zwitterionic phosphatidylcholine/cholesterol (10:1, w/w) vesicles, which mimic eukaryotic membranes. Furthermore, Pep-1-K caused little or no dye leakage from negatively charged phosphatidylethanolamine/phosphatidylglycerol (7:3, w/w) vesicles, which mimic bacterial membranes but had a potent ability to cause depolarization of the cytoplasmic membrane potential of intact S. aureus cells. These results suggested that Pep-1-K kills microorganisms by not the membrane-disrupting mode but the formation of small channels that permit transit of ions or protons but not molecules as large as calcein.
In this work, a 2D covalent triazine-based framework was prepared by using 1,3-dicyanobenzocthiophene（DCBT） as monomer to effectively capture CO2. The resulting CTF-DCBT was characterized by FT-IR, ...XPS, PXRD, elemental analysis, SEM, TEM, and N2 adsorption-desorption.The results indicate that CTF-DCBT is partially crystalline and has ultramicropore（6.5 A?） as well as high heteroatom contents（11.24 wt% and 12.61 wt% for N and S, respectively）. In addition, the BET surface area and total pore volume of CTF-DCBT are 500 m2/g and 0.26 cm3/g, respectively. CTF-DCBT possesses excellent thermal stability（450 °C） and chemical stability towards boiling water, 4 M HCl, and 1 M Na OH.The CO2 adsorption capacity of CTF-DCBT is 37.8 cm3/g at 1 bar and 25 °C. After six adsorption-desorption cycles, there is no obvious loss of CO2 uptake observed. Due to the ultramicropore and high heteroatom contents, CTF-DCBT has high isosteric heats of adsorption for CO2 and high selectivities of CO2 over N2 and CH4. At 25 °C, the CO2/N2 and CO2/CH4 selectivities are 112.5 and 10.3, respectively, which are higher than those of most POFs. Breakthrough curves indicate that CTF-DCBT could effectively separate CO2/N2 and CO2/CH4 mixtures.
To investigate the effect of Pro → peptoid residue substitution on cell selectivity and the mechanism of antibacterial action of Pro-containing β-turn antimicrobial peptides, we synthesized ...tritrpticin-amide (TP, VRRFPWWWPFLRR-NH2) and its peptoid residue-substituted peptides in which two Pro residues at positions 5 and 9 are replaced with Nleu (Leu peptoid residue), Nphe (Phe peptoid residue), or Nlys (Lys peptoid residue). Peptides with Pro → Nphe (TPf) or Pro → Nleu substitution (TPl) retained antibacterial activity but had significantly higher toxicity to mammalian cells. In contrast, Pro → Nlys substitution (TPk) increased the antibacterial activity but decreased the toxicity to mammalian cells. Tryptophan fluorescence studies indicated that the bacterial cell selectivity of TPk is closely correlated with a preferential interaction with negatively charged phospholipids. Interestingly, TPk was much less effective at depolarizing of the membrane potential of Staphylococus aureus and Escherichia coli spheroplasts and causing the leakage of a fluorescent dye entrapped within negatively charged vesicles. Furthermore, confocal laser-scanning microscopy showed that TPk effectively penetrated the membrane of both E. coli and S. aureus and accumulated in the cytoplasm, whereas TP and TPf did not penetrate the cell membrane but remained outside or on the cell membrane. These results suggest that the bactericidal action of TPk is due to inhibition of the intracellular components after penetration of the bacterial cell membrane. In addition, TPK with Lys substitution effectively depolarized the membrane potential of S. aureus and E. coli spheroplasts. TPK induced rapid and effective dye leakage from bacterial membrane-mimicking liposomes and did not penetrate the bacterial cell membranes. These results suggested that the ability of TPk to penetrate the bacterial cell membranes appears to involve the dual effects that are related to the increase in the positive charge and the peptide's backbone change by peptoid residue substitution. Collectively, our results showed that Pro → Nlys substitution in Pro-containing β-turn antimicrobial peptides is a promising strategy for the design of new short bacterial cell-selective antimicrobial peptides with intracellular mechanisms of action.
Therapeutic radiopharmaceuticals combine radionuclides with carriers. It uses radionuclide suitable radiation energy and range in the tissue, selectively concentrated irradiation of diseased tissue, ...while avoiding damage to normal tissue and achieving the desired therapeutic effect. It is mainly used for cancer treatment or relief of tumor-related symptoms. It is widely used in tumor diagnosis and treatment, myocardial imaging, early detection of neurodegenerative diseases and imaging diagnosis of inflammatory tissues. In recent years, with the rapid development of targeted ligands and the wide application of new medical nuclides, radiotherapeutic drugs have attracted more and more attention. At present, nuclides such as 153Sm, 89Sr, 223Ra, 90Y, 131I and 177Lu are commonly used to treat cancer, bone metastasis, liver cancer and thyroid cancer, and show exciting potential in treatment. The research on radiotherapeutic drugs is also increasing rapidly. The clinical application and development status of radiopha
The fusion of VISI (visual identity system Internet), digital maps and Web GIS is presented. Web GIS interface interactive design with VISI needs to consider more new factors. VISI can provide the ...design principle, elements and contents for the Web GIS. The design of the Wuhan Bus Search System is fulfilled to confirm the validity and practicability of the fusion.
Hepatic lipid metabolism is closely associated with certain diseases, such as obesity, diabetes, fatty liver, and hepatic fibrosis. Hepatic steatosis results from systemic metabolic dysfunction that ...occurs via multiple processes. The initial process has been characterized as hepatic lipid accumulation that may be caused by increased liver lipid uptake and de novo lipogenesis or decreased lipid oxidation and lipid export; subsequently, multiple additional factors that trigger inflammation and insulin resistance (IR) aggravate the progression of hepatic steatosis. Emerging evidence indicates that inflammation stands at the crossroads of innate immunity and lipid metabolism and links the initial metabolic stress and subsequent metabolic events in lipid metabolism. Therefore, in this review, we summarize the regulatory role of innate immune signaling molecules in maintaining lipid metabolic homeostasis; these revelations can guide the development of potential therapies for nonalcoholic fatty liver disease (NAFLD).
Materials genomics represents a research mode for materials development, for which reliable methods for efficient materials construction are essential. Here we present a methodology for ...high-throughput construction of covalent organic frameworks (COFs) based on materials genomics strategy, in which a gene partition method of genetic structural units (GSUs) with reactive sites and quasi-reactive assembly algorithms (QReaxAA) for structure generation were proposed by mimicking the natural growth processes of COFs, leading to a library of 130 GSUs and a database of ~470,000 materials containing structures with 10 unreported topologies as well as the existing COFs. As a proof-of-concept example, two generated 3D-COFs with ffc topology and two 2D-COFs with existing topologies were successfully synthesized. This work not only presents useful genomics methods for developing COFs and largely extended the COF structures, but also will stimulate the switch of materials development mode from trial-and-error to theoretical prediction-experimental validation.
Silkworms are insects with important economic value, and mulberry leaves are the food of silkworms. The quality and quantity of mulberry leaves have a direct impact on cocooning. Mulberry leaves are ...often infected with various diseases during the growth process. Because of the subjectivity and time-consuming problems in artificial identification of mulberry leaf diseases. In this work, a multi-scale residual network fusion Squeeze-and-Excitation Networks (SENet) is proposed for mulberry leaf disease recognition. The mulberry leaf disease dataset was expanded by performing operations such as brightness enhancement, contrast enhancement, level flipping and adding Gaussian noise. Multi-scale convolution was used instead of the traditional single-scale convolution, allowing the network to be widened to obtain more feature information and avoiding the overfitting phenomenon caused by the network piling up too deep. SENet was introduced into the residual network to enhance the extraction of key feature information of the model, thus improving the recognition accuracy of the model. The experimental results showed that the method proposed in this paper can effectively improve the recognition performance of the model. The recognition accuracy reached 98.72%. The recall and F1 score were 98.73% and 98.72% respectively. Compared with some other models, this model has better recognition effect and can provide technical reference for intelligent mulberry leaf disease detection.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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