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71.
Prawns (Penaeus monodon) were obtained from ponds in Iloilo, Philippines, in 1984 and 1985 and maintained in salinities from 8 to 44. Total hemolymph calcium was largely affected by molt stage and less so by salinity. A sharp, transient increase in hemolymph calcium occurred 3 to 6 h postmolt, followed by an equally rapid decrease from 6 h postmolt to intermolt. This biphasis response was limited to prawns in 8, 20 and 32S; in 44S, hemolymph calcium remained the same throughout the sampling period. Peak concentrations of total calcium were greater in low (8 and 20S) than in high salinities. Salinity had no effect on the duration of molt cycle nor on time of occurrence of molt. Almost half of molting incidents occurred between 18.01 and 0.00 hrs, and one-third between 0.01 and 06.00 hrs.  相似文献   
72.
Data were collected from managers in 24 nations/territories on work locus of control (LOC), individualism–collectivism (I–C), and well‐being (job satisfaction, absence of psychological strain, and absence of physical strain). There were significant mean differences across samples on all five of these measures, and consistent with our hypothesis, at the ecological or sample mean level well‐being was associated with an internal locus of control. However, contrary to our hypothesis, well‐being was not associated with I–C, despite a strong correlation between I–C and LOC. Findings at the ecological level were consistent with the literature concerning the salutary effects of control on well‐being. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
73.
Goal, Scope and Background In this paper, we attempt to elucidate the composition and origin of the orange patina on the surfaces of the West-Porch of Salisbury Cathedral by comparison to other known patinas: (i) the orange-brown patina on the marble surfaces of the Acropolis in Athens and the Arch of Titus in Rome whose analyses have shown very high amounts of phosphates, and generally amino acids from animal-skin glue or other protein binders; (ii) the phosphated patinas which also contain oxalates, found in 1996 on Catalonian calcareous sandstones and in the calcareous dolomites of the Monastery of Silos, Spain, whose origin is either the application of calcium caseinate, or egg yolk and animal glue; and (iii) the patinas with only oxalates found in some of Verona's monuments (St Zeno) and Spanish sites as in the Monastery of Guadalupe and Cuenca cathedral, formed either by the mineralization of algal filaments or by biological reactions yielding oxalate from yolk egg (added to stone as part of preservative empirical treatments). Methods In the winter of 2003, the West-Porch of Salisbury Cathedral received conservation works, but the old patina was not entirely removed. This fact has allowed us to collect the samples for its study. The IR spectra were registered with a Golden Gate ATR Mk II system using attenuated total reflectance Fourier transform infrared (ATR/FTIR) spectrometry. Mineral composition was determined by XRD (Philips PW 1710 spectrometer with Cu tube), whereas major and trace elements analyses were performed by XRF (Philips PW1480 PW). Microscopy examination was performed on a Leica M655 microscope. Phosphate, oxalate, calcium and sulphate contents were analysed by usual chemical methods. Results ATD-FTIR spectra of the Salisbury's patina exhibit peaks at 2361, 2341 and 671 cm–1 (assigned to phosphates); 3410, 1680, 1620, 1122 and 602 cm–1 (assigned to sulphates); and 1447/1437 and 876 cm–1 (attributed to carbonates). The little peaks at 1620 and 798 cm–1 could be assigned to oxalates. XRD and XRF have led to identify the carbonates, phosphates and sulphates as pertaining to the species dolomite, hydroxyapatite and gypsum, respectively. Oxalates are detected only in small amounts by chemical analyses but wewellite and weddellite have not been well identified. The interface between the patina and the calcareous dolomite is very uneven and full of cavities in certain cases, but well-defined and rather smooth in other cases. In accord with the very small amounts of the oxalates found, remnants of micro-organisms are not detected in the patinas. Discussion The Salisbury's patina is a composite material formed by particulates and matrix constituents. Regarding the patina particulate, e.g. animal bones, it is necessary to refer to the apatite phase composition. The bone mineral contains 4–8 wt % of carbonate in animal body and its presence in the apatite phase is advantageous as it increases the mechanical strength. We think that FTIR bands at around 1440 and 876 cm–1 arise from vibration of CO32– ions, but not necessarily from the limestone. They could be attributed to carbonated hydroxyapatite through the substitution of groups PO43– for CO32– in the lattice of hydroxyapatite. Concerning the matrix and also from the FTIR spectra, the absence of specific bands of the following species: proteins (3350–3225, 1660, 1550–1535, 1270–1230 and 620 cm–1), oils (1778, 1738 and 1051 cm–1), bee waxes (3000, 1470, 720–730 and 1700 cm–1) and aged egg-yolk (2954, 2920, 2850, 1650, 1549, 1465 and 1240 cm–1) had led us to exclude these usual binders. On the other hand, the amount of sulphates in the paste that covers the walls of the Salisbury's Cathedral is excessively high (above 20% in weight) to consider it as a biotransformation product of calcium oxalate from fungal biofilms. Consequently, we must think that the gypsum found in the samples has a man-made origin (it was deliberately added as part of a protective paste) and that it is the matrix searched for. Thus, we deduce that the patina of Salisbury's Cathedral is a special stucco made mixing plaster with powdered bone (the colour of the bones is the same that it exhibits in the patina), low quantities of an uncharacterized binder (collagen, possibly) and water. Conclusion We believe that the patina of the Salisbury's Cathedral is a variant of the Greco-Latin empirical protective treatment that included bone as a hardening material. Nevertheless, we also think that the presence of the bones in the paste could be related to an aesthetical intention: gaining a warm tone for the original stone through the ochre colour of the bones. Recommendation and Perspective Our results have been an excuse to contribute to the controversy started at the 80's on the origin of orange-brown patinas observed on stone surfaces of Greco-Latin and medieval monuments. There are two major theories on provenance: biological vs. man-made. In Salisbury Cathedral, neither of them has been proven through scientific evidence as yet. Our opinion is that Salisbury patina can be classified into the man-made group.  相似文献   
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76.
Few studies have explored the relationships between nation‐building, disaster risk reduction and climate change adaptation. Focusing on small island developing states, this paper examines nation‐building in Timor‐Leste, a small island developing state that recently achieved independence. Nation‐building in Timor‐Leste is explored in the context of disaster risk reduction, which necessarily includes climate change adaptation. The study presents a synopsis of Timor‐Leste's history and its nation‐building efforts as well as an overview of the state of knowledge of disaster risk reduction including climate change adaptation. It also offers an analysis of significant gaps and challenges in terms of vertical and horizontal governance, large donor presence, data availability and the integration of disaster risk reduction and climate change adaptation for nation‐building in Timor‐Leste. Relevant and applicable lessons are provided from other small island developing states to assist Timor‐Leste in identifying its own trajectory out of underdevelopment while it builds on existing strengths.  相似文献   
77.
Shellfish complying with European Regulations based on quantification of fecal bacterial indicators (FIB) are introduced into markets; however, information on viruses, more stable than FIB, is not available in the literature. To assess the presence of noroviruses (NoVs) GI and GII and human adenoviruses (HAdV) in domestic and imported mussels and clams (n = 151) their presence was analyzed during winter seasons (2004–2008) in north-west Spanish markets through a routine surveillance system. All samples tested negative for NoV GI and 13 % were positive for NoV GII. The role of HAdV as viral indicator was evaluated in 20 negative and 10 positive NoV GII samples showing an estimated sensitivity and specificity of HAdV to predict the presence of NoV GII of 100 and 74 % (cut-off 0.5). The levels of HAdV and NoVs and the efficiency of decontamination in shellfish depuration plants (SDP) were evaluated analyzing pre- and post-depurated mussels collected in May–June 2010 from three different SDP. There were no statistically significant differences in the prevalence and quantification of HAdV between pre- and post-depurated shellfish and between seawater entering and leaving the depuration systems. Moreover, infectious HAdV were detected in depurated mussels. These results confirm previous studies showing that current controls and depuration treatments limiting the number of FIB do not guarantee the absence of viruses in shellfish.  相似文献   
78.
This work proposes a procedure for the determination of total selenium content in shellfish after digestion of samples in block using cold finger system and detection using atomic fluorescent spectrometry coupled hydride generation (HG AFS). The optimal conditions for HG such as effect and volume of prereduction KBr 10 % (m/v) (1.0 and 2.0 ml) and concentration of hydrochloric acid (3.0 and 6.0 mol L?1) were evaluated. The best results were obtained using 3 mL of HCl (6 mol L?1) and 1 mL of KBr 10 % (m/v), followed by 30 min of prereduction for the volume of 1 mL of the digested sample. The precision and accuracy were assessed by the analysis of the Certified Reference Material NIST 1566b. Under the optimized conditions, the detection and quantification limits were 6.06 and 21.21 μg kg?1, respectively. The developed method was applied to samples of shellfish (oysters, clams, and mussels) collected at Todos os Santos Bay, Bahia, Brazil. Selenium concentrations ranged from 0.23?±?0.02 to 3.70?±?0.27 mg kg?1 for Mytella guyanensis and Anomalocardia brasiliana, respectively. The developed method proved to be accurate, precise, cheap, fast, and could be used for monitoring Se in shellfish samples.  相似文献   
79.
The contamination of water resources by metallic ions is a serious risk to public health and the environment. Therefore, a great emphasis has been given to alternative biosorption methods that are based on the retention of aqueous-solution pollutants; in the last decades, several agricultural residues have been explored as low-cost adsorbent. In this study, the ability of Pb (II) biosorption using sugarcane bagasse modified by different fungal species was evaluated. The presence of carbonyl, hydroxyl, and carboxyl groups in the biosorbent was observed by spectroscopy in the infrared region. By scanning electron microscopy, changes in the morphology of modified material surfaces were observed. The highest adsorption capacity occurred at pH 5.0, while the shorter adsorbate-adsorbent equilibrium was at 20 min, and the system followed the pseudo-second-order model. The maximum biosorption in isotherms was found at 58.34 mg g?1 for modified residue by Pleurotus ostreatus U2-11, and the system followed the Langmuir isotherm. The biosorption process was energetically spontaneous with low desorption values. This modification showed great potential for filters to remove Pb (II) and provide the preservation of water resources and animal health.  相似文献   
80.
Contemporary human activities such as tropical deforestation, land clearing for agriculture, pest control and grassland management lead to biomass burning, which in turn leads to land-cover changes. However, biomass burning emissions are not correctly measured and the methods to assess these emissions form a part of current research area. The traditional methods for estimating aerosols and trace gases released into the atmosphere generally use emission factors associated with fuel loading and moisture characteristics and other parameters that are hard to estimate in near real-time applications. In this paper, fire radiative power (FRP) products were extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) and from the Geostationary Operational Environmental Satellites (GOES) fire products and new South America generic biomes FRE-based smoke aerosol emission coefficients were derived and applied in 2002 South America fire season. The inventory estimated by MODIS and GOES FRP measurements were included in Coupled Aerosol-Tracer Transport model coupled to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) and evaluated with ground truth collected in Large Scale Biosphere–Atmosphere Smoke, Aerosols, Clouds, rainfall, and Climate (SMOCC) and Radiation, Cloud, and Climate Interactions (RaCCI). Although the linear regression showed that GOES FRP overestimates MODIS FRP observations, the use of a common external parameter such as MODIS aerosol optical depth product could minimize the difference between sensors. The relationship between the PM2.5μm (Particulate Matter with diameter less than 2.5 μm) and CO (Carbon Monoxide) model shows a good agreement with SMOCC/RaCCI data in the general pattern of temporal evolution. The results showed high correlations, with values between 0.80 and 0.95 (significant at 0.5 level by student t test), for the CATT-BRAMS simulations with PM2.5μm and CO.  相似文献   
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