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This paper furthers an understanding of the moral economy of tourism by analyzing how economic activities in the tourism industry are influenced by moral norms, and how these norms are compromised by the logic of capital accumulat...
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This paper furthers an understanding of the moral economy of tourism by analyzing how economic activities in the tourism industry are influenced by moral norms, and how these norms are compromised by the logic of capital accumulation. Through a case study of indigenous entrepreneurs in Lijiang, China, we argue that responsibility is a localized practice to defend social ties and cultural tradition, while profit making can be regarded as a universal logic in a commercial society. By analyzing how entrepreneurs become entangled in the dynamic balance between profit making and social responsibility, this paper demonstrates that local people actively choose their best strategies to participate in the global tourism industry.
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Some tertiary amines in the series of 1,3-di-amino-propan-2-ol, referred as 1,3-di-morpholin-4-yl-propan-2-ol (DMP) and 1,3-bis-diethylamino-propan-2-ol (DEAP), had been synthesized by alkylation reaction. These compounds were che...
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Some tertiary amines in the series of 1,3-di-amino-propan-2-ol, referred as 1,3-di-morpholin-4-yl-propan-2-ol (DMP) and 1,3-bis-diethylamino-propan-2-ol (DEAP), had been synthesized by alkylation reaction. These compounds were checked by MS, IR, ~1H NMR and ~(13)C NMR. The electrochemical performance of these products was investigated through potentiodynamic polarization measurement and electrochemical impedance spectroscopy (EIS) under thin electrolyte layer with thickness of 100 μm, and their inhibition efficiencies were measured using gravimetric method. These compounds, retarding the anodic dissolution of iron by the protective layer bonding on the metal surface, were anodic inhibitors under thin electrolyte layer. Polarization data indicated that the inhibitive performance of DMP for carbon steel was improved with the increasing of concentration, whereas DEAP showed a maximum inhibiting power at 2.5 × 10~(-2) M. The values of the charge transfer resistance, obtained from impedance plots of carbon steel, showed that DEAP was a promising inhibitor. The gravimetric results showed that the inhibition efficiency of DEAP at 2.5 × 10~(-2) M was 95%. The adsorption on the carbon steel surface followed Langmuir isotherm model. The Fourier transform spectroscopy (FTIR) was used to analyze the surface adsorbed film.
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In this study, the three-dimensional fluorescence spectroscopic technique was applied to discriminate the wines with different variety, brewery and vintage. A total of 42 wines produced in geographic origin of Changli county were ...
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In this study, the three-dimensional fluorescence spectroscopic technique was applied to discriminate the wines with different variety, brewery and vintage. A total of 42 wines produced in geographic origin of Changli county were analyzed. The results showed that the three-dimensional fluorescence spectra of wine samples with different variety, brewery and vintage had different fluorescence peaks. The fluorescence peaks were found in excitation wavelengths 260 , 290 and 329 nm. However, the number, location and fluorescenece intensity varied with the types of wines. The fluorescence spectra of the wine samples were evaluated using principal component analysis (PCA). PCA performed on the whole collection of three-dimensional fluorescence spectra allowed for a wide range of wine samples. These results showed that three-dimensional fluorescence spectroscopy may provide useful fingerprints that can determine the identity of wines from the Changli region.
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Stud shear connectors are the most widely used shear connectors in steel-concrete composite beams. The composite action of steel beam and concrete slab is effected by the stud shear properties directly. Thirty push-out tests on st...
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Stud shear connectors are the most widely used shear connectors in steel-concrete composite beams. The composite action of steel beam and concrete slab is effected by the stud shear properties directly. Thirty push-out tests on stud shear connectors were conducted to investigate the effects of stud diameter and height, concrete strength, stud welding technique, transverse reinforcement, and steel beam type on stud failure mode, load versus slip curve, and the shear bearing capacity. Based on the push-out test results, the stud shear mechanism was analyzed, a new expression of stud load-slip relationship was put forward, and a calculation model of stud shear bearing capacity was proposed taking into account the influences of stud diameter and height, material strength, and elastic modulus. Compared with existing models, the computed shear bearing capacities of the proposed calculation model had a better match with the experimental values.
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Soluble ionic aluminum (Al) inhibits root growth and reduces crop production on acid soils. Al-resistant cultivars of barley (Hordeum vulgare L.) detoxify Al by secreting citrate from the roots, but the responsible gene has not be...
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Soluble ionic aluminum (Al) inhibits root growth and reduces crop production on acid soils. Al-resistant cultivars of barley (Hordeum vulgare L.) detoxify Al by secreting citrate from the roots, but the responsible gene has not been identified yet. Here, we identified a gene (HvAACT1) responsible for the Al-activated citrate secretion by fine mapping combined with microarray analysis, using an Al-resistant cultivar, Murasakimochi, and an Al-sensitive cultivar, Morex. This gene belongs to the multidrug and toxic compound extrusion (MATE) family and was constitutively expressed mainly in the roots of the Al-resistant barley cultivar. Heterologous expression of HvAACT1 in Xenopus oocytes showed efflux activity for 14C-labeled citrate, but not for malate. Two-electrode voltage clamp analysis also showed transport activity of citrate in the HvAACT1-expressing oocytes in the presence of Al. Overexpression of this gene in tobacco enhanced citrate secretion and Al resistance compared with the wild-type plants. Transiently expressed green fluorescent protein-tagged HvAACT1 was localized at the plasma membrane of the onion epidermal cells, and immunostaining showed that HvAACT1 was localized in the epidermal cells of the barley root tips. A good correlation was found between the expression of HvAACT1 and citrate secretion in 10 barley cultivars differing in Al resistance. Taken together, our results demonstrate that HvAACT1 is an Al-activated citrate transporter responsible for Al resistance in barley.
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In higher plants, class I KNOTTED1-like homeobox (KNOX) gene suppression and leaf polarity establishment are two processes crucial for leaf morphogenesis. The Arabidopsis genes, ASYMMETRIC LEAVES1 and 2 (AS1 and AS2), are required...
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In higher plants, class I KNOTTED1-like homeobox (KNOX) gene suppression and leaf polarity establishment are two processes crucial for leaf morphogenesis. The Arabidopsis genes, ASYMMETRIC LEAVES1 and 2 (AS1 and AS2), are required for repressing the class I KNOX genes and promoting leaf adaxial cell fates. In addition, the RNA-DEPENDENT RNA POLYMERASE6 (RDR6) gene acts synergistically with AS1 and AS2 to specify the adaxial polarity and repress the KNOX genes in leaves. It is known that RDR6 is one of the key components in plant post-transcriptional gene silencing (PTGS), and is likely to function with other silencing components in a genetic pathway in regulating leaf patterning. Here we report phenotypic analyses of double mutants combining as1 or as2 with other mutations relating to different RNA silencing pathways. We show that plants carrying rdr6, suppressor of gene silencing3 (sgs3) or zippy (zip, also called ago7) in combination with as1 or as2 demonstrate severe morphological defects, and the double mutant plants are generally similar to one another. Detailed phenotypic and molecular analyses reveal that leaves of rdr6 as2(1), sgs3 as2(1) and zip as2(1) all show an abnormal adaxial identity, and contain high levels of microRNA165/166 and FILAMENTOUS FLOWER (FIL) transcripts. These results suggest that RDR6, SGS3 and AGO7 act in the same pathway, which genetically interacts with the AS1–AS2 pathway for leaf development. The RDR6–SGS3–AGO7 pathway was previously identified as regulating the plant vegetative phase change. Our results reveal a new function of the pathway, which is also required for normal leaf morphogenesis.
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BACKGROUND: The objective of this study was to compare the clinical features and prognosis of patients with diffuse large B-cell lymphoma (DLBCL) of Waldeyer ring (WR-DLBCL) and patients with lymph node-DLBCL (N-DLBCL). METHODS: O...
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BACKGROUND: The objective of this study was to compare the clinical features and prognosis of patients with diffuse large B-cell lymphoma (DLBCL) of Waldeyer ring (WR-DLBCL) and patients with lymph node-DLBCL (N-DLBCL). METHODS: One hundred eighty-one patients with WR-DLBCL and N-DLBCL were reviewed. There were 57 patients with stage I disease, 83 patients with stage II disease, 26 patients with stage III disease, and 15 patients with stage IV disease. Among them, 101 patients had primary N-DLBCL. and 80 patients had primary WR-DLBCL. RESULTS: Patients with WR-DLBCL and N-DLBCL usually presented at an older age and had localized disease, a low frequency of B symptoms, a good performance status, and a low-risk International Prognostic Index (IPI) score. Compared with patients who had N-DLBCL, patients who had WR-DLBCL presented with more stage II disease and lower tumor burdens. The overall response rate after treatment was similar in both groups. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 76% and 61% in patients with WR-DLBCL, respectively, and 56% and 50% in patients with N-DLBCL, respectively (P = .119 for OS; P = .052 for PFS). IPI scores and elevateci P2-microglobulin and LDH levels were associated with a poor prognosis for patients who had WR-DLBCL: whereas bulky tumor, elevated p2-microglobulin levels, and IPI scores were associated with poor OS for patients who had N-DLBCL. CONCLUSIONS: The current results supported the continued inclusion of WR-DLBCL as a lymph node group in the staging of DLBCL. Patients with WR-DLBCL had clinical feature-and prognosis similar to those of patients with N-DLBCL.
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The HIV-1 LTR controls the expression of HIV-1 viral genes and thus is critical for viral propagation and pathology. Numerous host factors have been shown to participate in the regulation of the LTR promoter. Among them is the thy...
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The HIV-1 LTR controls the expression of HIV-1 viral genes and thus is critical for viral propagation and pathology. Numerous host factors have been shown to participate in the regulation of the LTR promoter. Among them is the thyroid hormone (T3) receptor (TR). TR has been shown to bind to the critical region Of the promoter that contain the NFkB and Sp1 binding sites. Interestingly, earlier transient transfection Studies in tissue culture cells have yielded contradicting conclusions on the role of TR in LTR regulation, Likely due to the use of different cell types and/or lack of proper chromatin organization.
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A new approach to construct a reagentless electrochemical H_2O_2 sensor is described. Iron oxide magnetic nanocystals (IOMNs), as peroxidase mimetics, were assembled to form a multilayer structure through the layer-by-layer (LBL) ...
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A new approach to construct a reagentless electrochemical H_2O_2 sensor is described. Iron oxide magnetic nanocystals (IOMNs), as peroxidase mimetics, were assembled to form a multilayer structure through the layer-by-layer (LBL) method. Polythionin (PTh) was first electrodeposited onto the glassy carbon electrode (GCE) surface to introduce amino groups. Carboxyl functionalized multi-walled carbon nan-otubes (MWCNTs), amino functionalized IOMNs, and thionin monomers were alternatively anchored onto a polythionin-functionalized GCE surface in order by carbodiimide or glutaraldehyde chemistry. The resulting multilayer construction with three layers of IOMNs and thionin mediator exhibits excellent electrochemical response to the reduction of H_2O_2, whereas such a modified electrode with one layer construction only yields a slight response to H_2O_2 of the same concentration. The tethered MWCNTs enlarge the amount of immobilized IOMNs and effectively shuttle electrons between the electrode and the thionin. The calibration plot is linear over the wide H_2O_2 concentration range from 0.099 to 6.54 mM, with a detection limit of 53.6 μM.
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摘要 :
SAFETY requirements are some of themost critical aspects of the
definition of an operational profile for a rendezvous mission [1].
Numerous methods for generating safe rendezvous trajectories have
been reported in the literatur...
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SAFETY requirements are some of themost critical aspects of the
definition of an operational profile for a rendezvous mission [1].
Numerous methods for generating safe rendezvous trajectories have
been reported in the literature. Early representative work in this
regard can be found in [2,3]. Hechler [2] proposed amethod of linear
optimization for minimum-fuel rendezvous that considers the
constraints of collision avoidance if the chaser is operating out of
control. Eckstein [3] proposed an approach that is based on the
Clohessy–Wiltshire (C–W) equations for the design of approach
trajectories toward an orbiting space station, with an emphasis on
safety aspects. Recently, Roger and McInnes [4] planned passively
safe trajectories using potential functions. Jacobsen et al. [5]
presented a numerical optimization method that employs both safety
and fuel as optimization objectives in the planning of a safe spatial
trajectory of a robot capturing an uncontrolled spinning satellite. This
method was also applied by Matsumoto et al. [6]. Fehse [1] and
Naasz [7] developed the safety ellipsemethod for the analysis of safe
approach trajectories.More recently, Breger and How [8] proposed a
method for the onboard generation of safe fuel-optimized rendez-
vous trajectories that guarantee collision avoidance for a large class
of anomalous system behaviors. They also examined the tradeoffs
between passive and active approaches to safety.
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