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1.
A worldwide survey of babirusa skulls curated in museum and private collections located 431 that were from adult males and had retained at least one maxillary canine tooth. Eighty-three of these skulls were identified as exhibiting aberrant maxillary canine tooth growth. Twenty-four of the skulls represented babirusa from Buru and the Sula Islands, and forty-five skulls represented babirusa from Sulawesi and the Togian Islands. The remaining series of fourteen babirusa skulls originally came from zoo animals. Fifteen skulls showed anomalous alveolar and tooth rotation in a median plane. Twenty-nine skulls had maxillary canine teeth that did not grow symmetrically towards the median plane of the cranium. Fourteen skulls showed evidence that the tips of one or both maxillary canine teeth had eroded the nasal bones. Twenty-one skulls had maxillary canine teeth that had eroded the frontal bones. The teeth of two skulls had eroded a parietal bone. One skull had two maxillary canines arising from an adjacent pair of alveoli on the left side of the cranium. Three skulls exhibited alveoli with no formed maxillary canine teeth in them. Analysis suggested that approximately 12% of the adult male babirusa in the wild experience erosion of the cranial bony tissues as a result of maxillary canine tooth growth. There was no skeletal evidence that maxillary canine teeth penetrate the eye.  相似文献   

2.
Abstract: The complete skull of an anomalous odontocete cetacean from outer Disko Bay, West Greenland, is described and compared with the skulls of adult narwhals, Monodon monoceros , and belugas, Delphinapterus leucas . The anomalous whale's skull is much larger than those of normal narwhals and belugas. In particular, the rostrum and mandibles are relatively long and massive. The dentition is unlike that of any known cetacean, but some features of the teeth are considered analogous to those of both narwhals and belugas. The intermediate characteristics of the skull and dentition are consistent with the hypothesis that the anomalous whale was a narwhal-beluga hybrid.  相似文献   

3.
A new technique for investigation of elemental concentrations in subfractions of blood plasma is presented. The method is composed of the ultrafiltration of plasma in the presence of ethylenediaminetetraacetic acid (EDTA) and the measurement of the elemental composition by proton-induced X-ray emission (PIXE). The blood samples were collected from both healthy persons and patients suffering from breast cancer. The main emphasis in this study was on the determination of loosely bound copper (Cu) in plasma subfractions containing substances with molecular mass under 10,000, but zinc (Zn) and iron (Fe) contents of these fractions were also determined. The detection limits obtained with this method for Cu, Zn and Fe were ≈10 ppb (wet wt).  相似文献   

4.
Precise determination of the peptide content in drug substance samples depends highly upon the particular peptide compound and methodology used. Four independent methods were evaluated and compared to determine which would produce the best experimental precision for analysis of thymalfasin (thymosin alpha-1). Four different methods were evaluated including elemental analysis (CHN), quantitative amino acid analysis (AAA), high-performance liquid chromatography (HPLC), and Kjeldahl. This study demonstrates that the AAA method is highly variable in one laboratory while quite precise in another laboratory. Similarly, HPLC results depended on the laboratory conducting the study with more precise values obtained under cGMP. On the contrary, the CHN method yielded highly precise [i.e. <2% coefficient of variation (CV)] values. As precise knowledge of protein content is fundamental for the compounding of final pharmaceutical product of a specific potency, the CHN analysis is recommended for peptide content determination of the drug substance thymalfasin.  相似文献   

5.
The harpacticoid copepodTisbe holothuriae was cultivated at different densities in a running-water system. Dry weight and chemical composition (CHN) of both females and egg-sacs have been determined. Dry weight decreased significantly with increasing density from 3,48 to 1.94μg in egg-sacs, and from 10.80 to 6.58μg in females. Increasing density in both egg-sacs and females results in decrease of carbon, nitrogen and hydrogen contents, expressed as a percentage of dry weight of egg-sacs and females, respectively. Carbon decreases from 52.56 to 50.57% (egg-sacs) and 45.80 to 39.95% (⧫), nitrogen from 12.63 to 11.94% and 10.72 to 9.73% and hydrogen from 9.08 to 7.78% and 7.47 to 6.17%. The dry weight and elemental compositions of the egg-sacs varied in accordance with that of the females, however, a higher percentage of elemental content was observed in egg-sacs. The energy equivalents were calculated from the carbon content. This indicates that more energy was transferred from the maternal body into egg-sacs. The ratio of carbon to nitrogen did not show any marked variations; no clear relation appeared between C:N and density, indicating a relatively constant chemical composition in both females and egg-sacs.  相似文献   

6.
In this paper, bis(2 methyl-8-hydroxyquinoline) zinc (Zn(mq)2) nanoparticles were synthesised at room temperature by a simple chemical precipitation method. The Zn(mq)2 nanoparticles were characterised by powder X-ray diffraction (PXRD) analysis to confirm the crystalline nature of the Zn(mq)2 nanoparticles. The morphology and the elemental composition of Zn (mq)2 nanoparticles were analysed by high-resolution scanning electron microscopy (HR-SEM) and energy dispersive X-ray analysis (EDAX). The functional groups of the compound were studied with the help of Fourier transform infrared spectroscopy (FTIR) and FT Raman spectroscopy. Further, Zn (mq)2 nanoparticles were characterised by C-13 NMR spectroscopy, mass spectroscopy and CHN analysis. The thermal stability of the particles was studied using TG-DSC curve. The optical properties of the particles were studied by means of UV–Visible spectroscopy. The luminescence property of the synthesised particles was observed from the photoluminescence spectrum to confirm the possible application in organic light emitting diode.  相似文献   

7.
The soil microbial population, determined over a period of 19 months and the elemental chemical composition measured by X-ray fluorescence techniques were followed in two uncultivated salt-affected areas of Greece, namely Lantza and Klidi. The ecological conditions at Lantza remained stable during the period of study while at Klidi some ecological variations occurred. The present results indicate that in Lantza soil both the microbial population and the elemental chemical composition of the soil remained constant during the period of study while in Klidi alterations in both were observed.  相似文献   

8.
Chitosan is a polysaccharide used in a broad range of applications. Many of its unique properties come from the presence of amino groups in its structure. A proper quantification of these amino groups is very important, in order to specify if a given chitosan sample can be used in a particular application. In this work, a comparison between the determination of chitosan degree of deacetylation by conductometry and CHN elemental analysis was carried out, using a rigorous error analysis. Accurate expressions relating CHN composition, conductometric titration, and degree of deacetylation, in conjunction with their associated errors, were developed and reported in this note. Error analysis showed conductometric analysis as an inexpensive and secure method for the determination of the degree of deacetylation of chitosan.  相似文献   

9.
Cobalt hydroxide nanoparticles were prepared onto a carbon ceramic electrode (CHN|CCE) using the cyclic voltammetry (CV) technique. The modified electrode was characterized by X-ray diffraction and scanning electron microscopy. The results showed that CHN with a single-layer structure was uniformly electrodeposited on the surface of CCE. The electrocatalytic activity of the modified electrode toward the oxidation of insulin was studied by CV. CHN|CCE was also used in a homemade flow injection analysis system for insulin determination. The limit of detection (signal/noise [S/N] = 3) and sensitivity were found to be 0.11 nM and 11.8 nA/nM, respectively. Moreover, the sensor was used for detection of insulin in human serum samples. This sensor showed attractive properties such as high stability, reproducibility, and high selectivity.  相似文献   

10.
The elementary composition [Na, Mg, P, S, Cl, K, Ca and Fe] of the tegument, tegumental spines, and subtegumental tissues of adult male and female Schistosoma mansoni have been determined by electron probe X-ray microanalysis of unfixed, freeze-dried cryosections. Statistical analysis of the results suggests that there are distinct differences in the elemental composition of the tissues both between and within individual male and female worms, and between male and female worms in general. In particular, there were significant variations in the elemental contents of the tissues between individual male and female worms, which may reflect differences in the physiology and/or metabolic state of the worms. Significant differences in the elemental composition of the various tissues examined within individual worms were also found. In general, in both male and female worms, there were significantly higher elemental levels in the tegument, as opposed to the subtegumental tissues. The elemental composition of the tegumental spines in both male and female worms differed from that of the tegumental cytoplasm, although the differences in the elemental composition between spines from male and female worms reflected the differences in the elemental content between the teguments themselves. Differences in the elemental composition of the tissues between male and female worms were also found, with the female tegument containing significantly higher elemental levels (with the exception of Cl) than the male tegument. In particular, the tegument of female worms contained higher levels of calcium and, in relatively small areas, isolated calcium-containing granules. This higher tegumental calcium level in female worms may reflect a higher calcium demand by sexually mature female worms due to the presence, within the mature vitelline cells, of calcium-containing corpuscles and the production of large numbers of eggs.  相似文献   

11.
X-ray fluorescence microscopy was applied for two-dimensional elemental analysis of substantia nigra (SN) tissue. The samples representing Parkinson’s disease (PD) and control cases were examined at HASYLAB beamline L and at ESRF beamline ID22. Two-dimensional mapping of P, S, Cl, K, Ca, Fe, Cu, Zn, Se and Br was done with the spatial resolution of 15 and 5 μm. The masses per unit area of elements in neuromelanin reach nerve cells of SN were determined.The elemental data were processed using two multivariate techniques, namely cluster and discriminant analysis. The statistical methods were used for data reduction, both unsupervised and supervised classification as well as for the creation of a model that would simplify case identification based on the elemental analysis of SN tissue. The results of cluster analysis confirmed the statistical significance of the differences in elemental composition of PD and control SN nerve cells. Based on the results of discriminant analysis, the elements (P, Cl, Fe, Cu and Zn) that played the greatest role in the process of differentiation between neurons from examined groups were determined.  相似文献   

12.
Novel molybdenum complex, cis-[MoO2(phox)2] has been synthesized and characterized by IR, 1H NMR, elemental analyses (CHN), and X-ray molecular structure determination methods. This complex was found to be an efficient, selective catalyst for the oxidation of various sulfides to sulfoxides with urea hydrogen peroxide (UHP) in excellent yields (100% for diallylsulfide) and short reaction times (20 min) at room temperature. The catalytic system oxidizes diallylsulfide chemoselectively to its corresponding sulfoxide without any over oxidation in double bond.  相似文献   

13.
Measurements of the external opening of the tear duct (naso-lachrymal canal) of skulls of American colored males and white males indicate larger apertures among the former at corresponding ages. Duct length is somewhat shorter among colored males. In both racial samples the older skulls have slightly larger apertures than those under 40. A sample of white female skulls corroborates this, and manifests smaller average size than the white male skulls at ages below 50 whereas older skulls reveal no sex difference. The race difference in aperture size among male skulls is highly significant statistically and may reflect ecological adaptation.  相似文献   

14.
The analysis of fluctuating asymmetry (FA) allows for estimating the influence of stress factors on human development and allows to evaluate resistance to stress. FA is often used as a marker of prenatal stress. The aim of this work is to estimate the symmetry of skulls from selected historic human populations and to analyse changes in their morphology which have taken place over centuries. The studied material consisted of two skull samples - a modern sample containing 82 skulls and a medieval sample of 77 skulls from Gródek on the Bug River. Radiographs were taken in postero-anterior (P-A) and base projections. Images were scanned and calibrated by means of MicroStation 95 Academic Edition software. Measurements of the skull images were used to estimate FA. All data were analysed statistically. The skulls in both samples showed asymmetry. The levels of FA varied in different skull regions. A high level of FA in the calvaria and a low asymmetry for the facial part of skull is characteristic of modern skulls. In medieval skulls these relations are inverted. The higher value of FA in modern skulls is an evidence of a higher level of developmental stress in the modern population as well as of its lesser abilities to resist stress.  相似文献   

15.
Herpesviral infections have been documented in some cetaceans; however, they have not yet been identified in species in the western North Pacific. In the present study, 178 tissue samples from 76 stranded cetacean individuals were tested for the presence of herpesviruses. Herpesvirus genomic DNA fragments surrounding the DNA polymerase gene were amplified in samples from four individuals. TA cloning and direct sequencing of these DNA fragments revealed the presence of two novel alphaherpesviruses, and two novel gammaherpesviruses in the four cetacean individuals. The alphaherpesviruses were associated with the lung tissue of a false killer whale (Pseudorca crassidens), and with the mucus of a melon-headed whale (Peponocephala electra). The gammaherpesviruses were found in the lymph tissues of a Stejneger's beaked whale (Mesoplodon stejnegeri) and a sperm whale (Physeter macrocephalus). The phylogenetic tree using amino acid sequences of the DNA polymerase gene supported the inclusion of the novel viruses identified here in a single monophyletic group containing alphaherpesviruses from other Atlantic cetacean species. Conversely, the novel gammaherpesviruses formed an independent clade distant from other known cetacean gammaherpesviruses.  相似文献   

16.
A method based on X-ray microanalysis (XRMA) with the transmission electron microscope for measurement of total amounts of elements in single microbial cells has been developed. All major elements in cells except hydrogen can be measured simultaneously. XRMA provided N/C ratios (means (plusmn) standard errors of the mean) for stationary-phase and growing Escherichia coli of 0.23 (plusmn) 0.01 and 0.30 (plusmn) 0.01, respectively, while CHN analysis gave values of 0.276 and 0.307, respectively, for samples from the same cultures. Analyses of free coccoliths from Emiliana huxleyi provided weight fractions close to those of CaCO(inf3): 0.35 (plusmn) 0.01, 0.15 (plusmn) 0.01, and 0.47 (plusmn) 0.01 for calcium, carbon, and oxygen, respectively. Calibration is based on monodisperse latex beads and on microdrops of defined compounds. Elements in particles in the size range from 5 fg to 500 pg are measured with a relative precision between 500 and 5,000 ppm, depending on size. As a single-cell method, XRMA avoids the shortcomings of commonly used fractionation techniques associated with bulk methods, which are based on centrifugation or filtration. On the basis of morphology and XRMA, particles may be classified more precisely into groups (e.g., biotic versus abiotic) than is possible by bulk methods. Single-cell elemental analysis may provide insight into topics like nutritional and energetic status, macromolecular composition, and (by multivariate statistics) community structure.  相似文献   

17.
The Norway lobster, Nephrops norvegicus, is a commercially exploited decapod which is widely distributed throughout the north-eastern Atlantic and the Mediterranean Sea. Ovigerous females originating from the Mediterranean and the Irish Seas were held in the laboratory until larvae hatched. Biomass and biochemical composition, as well as digestive gland structure, were examined in newly hatched larvae from these two regions. In addition, previously published data from a North Sea population were included in our comparison. Elemental analyses showed that the absolute quantities of dry mass (DM), carbon (C), nitrogen (N) and hydrogen (H) (collectively referred to as CHN) per individual, and the C:N mass ratios, were significantly lower, while the relative CHN, protein and lipid values (in % of DM) were higher in samples from the Irish Sea compared to larvae originating from either the Mediterranean or the North Sea. As in CHN, the absolute level of protein per individual was higher in larvae from the Mediterranean, while no significant differences were observed in the individual lipid contents. Likewise, the digestive gland structure at hatching did not show any differences between study areas. Intraspecific variability in biomass and chemical composition of newly hatched larvae from different regions may be related to differential patterns of reproduction in regions with different climatic conditions. Lobster larvae hatch in the Mediterranean Sea predominantly in winter when both water temperature and planktonic food availability are at a minimum, while hatching in the Irish Sea occurs under more favourable conditions in spring. Hence, significantly higher wet mass, dry mass and protein values in Mediterranean larvae may represent adaptive traits allowing for early posthatching survival and development under food-limited conditions in an oligotrophic environment.Communicated by H.-D. Franke  相似文献   

18.
The large edible spider crab Maja brachydactyla Balss, 1922, an overexploited coastal fishery resource in Galicia (NW Spain), is considered as a potential aquaculture candidate. Patterns of its larval growth were studied under controlled laboratory conditions (constant 18 ± 1 °C; 36‰ salinity; photoperiod ca. 12:12 h; lipid-enriched Artemia metanauplii provided as food). From hatching through complete larval development and metamorphosis to the first juvenile crab instar, changes in carapace size, dry weight (DW), ash content, elemental composition (carbon, hydrogen, nitrogen; CHN), and proximate biochemical composition (total proteins, lipids, carbohydrates; Pr, L, Ch) were measured in successive stages (zoea I, II, megalopa, crab I). Body size may be described as a linear function of the number of molting cycles, whereas the amounts of DW, CHN, Pr, L, and Ch per individual increased exponentially (3 to 9 fold). The highest growth rates were observed in L, C and H, the lowest in DW, Pr and N. As a consequence of these patterns, the C:N mass ratio as well as the fractions of L, C and H (in % of DW) increased significantly, while those of Pr and N decreased from 26% to 16% of DW. Throughout development, however, Pr remained the principal biochemical component of total DW. Positive correlations between biochemical and CHN data allow for estimates of Pr from N and of L from C values per individual. The patterns of larval growth observed in M. brachydactyla are, in general, similar to those previously described for other brachyuran crabs with a planktotrophic mode of larval development.  相似文献   

19.
Wallander H  Pallon J 《Mycologia》2005,97(2):295-303
A laboratory experiment was performed to estimate the elemental composition of rhizomorphs of an ectomycorrhizal (EM) fungus growing in a patchy environment. Successive samples of Rhizopogon rhizomorphs, located adjacent to patches with organic matter or patches with acid-washed sand, were taken over a period of 45 d. The mass per unit area was analyzed with scanning transmission ion microscopy (STIM), and the elemental content of elements heavier than Mg were analyzed with particle induced X-ray emission (PIXE). Rhizomorphs associated with the organic matter on average were three times heavier per unit area than rhizomorphs associated with sand. The Ca concentration (mg g(-1)) increased in rhizomorphs adjacent to patches with sand, while it decreased in rhizomorphs adjacent to patches with organic matter. Fe concentration was higher in rhizomorphs adjacent to patches with sand. We concluded that the EM fungus responded to the organic matter by producing larger rhizomorphs, rather than increasing the concentration of elements in the rhizomorphs, to improve the transport of elements to the roots. The elemental composition of rhizomorphs varied considerably over time, and the accumulation of Ca in rhizomorphs in the sand-filled compartments could be the effect of acropetal flow of solutes from the plant roots toward the mycelial front.  相似文献   

20.
In the Seno de Reloncaví, southern Chile, seasonal changes in dry weight (DW) and elemental composition (CHN) were studied in embryo (initial embryonic stage), newly hatched zoeae, and newly settled megalopae of a porcelain crab, Petrolisthes laevigatus. Samples were taken throughout the seasons of egg laying (March-December), hatching (August-February), and settlement (October–February). Values of DW and CHN per embryo or larva, respectively, were consistently minimum in the middle of each season and maximum near its beginning and end. Patterns of seasonal variation in early embryonic biomass may thus be carried over to larvae at hatching and, possibly, to the settlement stage. Such carry-over effects may be selectively advantageous, as zoeae released at the beginning or near the end of the hatching season face conditions of poor planktonic food availability in combination with low winter temperatures or decreasing temperatures at the end of summer (enforcing long development duration). Hence, an enhanced female energy allocation into egg production may subsequently translate to enhanced yolk reserves remaining at hatching, allowing for a larval development under unfavourable winter conditions. In summer, by contrast, plankton productivity and temperatures are generally high, allowing for fast larval growth and development. This coincides with minimal biomass and energy contents both at hatching and settlement. In conclusion, our data suggest that seasonal patterns in the biomass of early developmental stages of P. laevigatus may reflect phenotypic variability as an adaptive response to predictable variations in environmental conditions, allowing this species to reproduce in temperate regions with marked seasonality in water temperature and plankton productivity.  相似文献   

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