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1.
《Comptes Rendus Palevol》2018,17(3):166-177
The avian fossil assemblages from the late Pleistocene deposits of the Rio Secco Cave (north-eastern Italy) is presented herein. We studied the layers that date back to the end of MIS3 and the beginning of MIS2, which also contain evidence of Gravettian frequentation dated to 33.5–30 ka cal BP. The systematic analysis revealed the presence of 18 species and other supraspecific taxa that supported palaeoenvironmental reconstructions. Taxa indicate that, at the onset of LGM, site surroundings were characterised by conifer or mixed forests, open grasslands, slow-flowing water bodies and mountain meadows with rocky outcrops, as indicated by Lagopus muta. Today, this environment is found above the tree line (beyond 1500–2000 m) and cannot be detected near the site, located at 580 m asl. Noteworthy, is also the finding of the second Italian late Pleistocene fossil record of Picus canus.  相似文献   

2.
《Process Biochemistry》2010,45(2):247-258
Response surface methodology was used to evaluate the quantitative effects of three independent variables: rapeseed moisture content (MC), enzymes dosage (ED) and conditioning temperature (T) on rapeseed oil yield (OY), efficiency of pressing (EP), and oxidative stability (OS). The highest OY (16.4%) and EP (42.8%) were obtained from pectolytic enzyme (0.1%) treated seeds (MC = 9%, T = 90 °C). The highest OS (12.6 h) was found for oil pressed from rapeseeds heated at 120 °C (MC = 11%), after the cellulolytic enzyme treatment. Results of OY, EP and OS determinations correlate with the predicted values calculated from the partial cubic models (PCMs) equations (R2 = 0.9995, 0.9994, 0.9974 for the cellulolytic enzyme-treated oils and 0.9900, 0.9900, 0.9990 for the pectolytic enzyme-treated oils). The predicted optimum MC = 9.5% and 8.6%, ED = 0.06% and 0.1%, T = 91.2 °C and 90.1 °C resulted in OY = 15.5% and 16.5%, EP = 40.4% and 43.0% for rapeseed oils from seeds treated with cellulolytic and pectolytic enzymes. OS values (12.6 h and 11.8 h) at the optimum conditions of MC = 11.0% and 10.1%, ED = 0.04% and 0.08%, T = 120.0 °C and 119.9 °C for the cellulolytic and pectolytic enzyme-treated oils were also calculated using PCM. Moreover, scanning electron microscopy revealed structural changes in the rapeseed after enzymatic treatment.  相似文献   

3.
《Comptes Rendus Palevol》2019,18(4):465-478
The northern edge of the Iranian Central Desert has provided valuable evidence of terminal Pleistocene human settlements. Mirak constitutes one of the largest open-air lithic scatters in the region, consisting of eight natural mounds. Fieldwork was initiated in 2015 by the joint Iranian-French program at Mirak 8. Preliminary results have demonstrated at least three successive phases of human occupation during the MIS3: an upper layer with clear Upper Paleolithic affinities and a maximum age of 28 ky, a lower layer with clear Middle Paleolithic affinities that dates around 47 ky, and an intermediate layer with mixed characteristics that can be seen as an intermediate Paleolithic phase which dates between 28 ± 2 and 38 ± 2 ky. At the time when Upper Paleolithic cultures originated in the Zagros Mountains, cultures with clear Middle Paleolithic affinities persisted nearby along the northern edge of the Iranian Central Plateau.  相似文献   

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6.
Senegal has since 2003 used sulphadoxine-pyrimethamine (SP) for Intermittent Preventive Treatment (IPT) of malaria in risk groups. However, the large-scale IPT strategy may result in increasing drug resistance. Our study investigated the possible impact of SP-IPT given to infants and children on the prevalence of SP-resistant haplotypes in the Plasmodium falciparum genes Pfdhfr and Pfdhps, comparing sites with and without IPTi/c. P. falciparum positives samples (n = 352) were collected from children under 5 years of age during two cross-sectional surveys in 2010 and 2011 in three health districts (two on IPTi/c and one without IPTi/c intervention) located in the southern part of Senegal. The prevalence of SP-resistance-related haplotypes in Pfdhfr and Pfdhps was determined by nested PCR followed by sequence-specific oligonucleotide probe (SSOP)–ELISA. The prevalence of the Pfdhfr double mutant haplotypes (CNRN and CICN) was stable between years at < 10% in the control group (P = 0.69), while it rose significantly in the IPTi/c group from 2% in 2010 to 20% in 2011 (P = 0.008). The prevalence of the Pfdhfr triple mutant haplotype (CIRN) increased in both groups, but only significantly in the IPTi/c group from 41% to 65% in 2011 (P = 0.005). Conversely, the Pfdhps 437G mutation decreased in both groups from 44.6% to 28.6% (P = 0.07) and from 66.7% to 47.5% (P = 0.02) between 2010 and 2011 in the control and the IPTi/c groups, respectively. Combined with Pfdhfr, there was a weak trend for decreasing prevalence of quadruple mutants (triple Pfdhfr + Pfdhps 437G) in both groups (P = 0.15 and P = 0.34). During the two cross-sectional surveys, some significant changes were observed in the SP-resistance-related genes. However, since these changes were observed in the two groups, the IPTi/c strategy does only seem to have limited impact on resistance development and other factors as well. However, continuous monitoring will be needed, due to the up-scaling of the IPTi/c strategy in Senegal according to WHO recommendations.  相似文献   

7.
Serum samples from 2970 (1400 sows, 1570 fattening) pigs, from 100 farms in the 10 main swine production regions in Spain were tested for antibodies against T. gondii by the modified agglutination test (MAT). Antibodies to T. gondii (MAT 1:25 or higher) were detected in 492 pigs (16.6%, 9.7% in fattening pigs and 24.2% in sows). The herd prevalence was 85.0% (95% CI: 78–92) and within-farm prevalence ranged from 2.9% to 92.8% (median = 17.6%). Statistically significant differences were observed among sampling regions with seroprevalence significantly higher in pigs from Valencia Community (27.3%), Extremadura (23.3%) and Catalonia (21.2%). A generalized estimating equations model indicated that the risk factors associated with T. gondii seroprevalence were: age, sows compared to fattening pigs (OR = 2.9; 95% CI = 1.83–4.53), lack of rodent control (OR = 1.9; 95% CI = 1.04–3.60) and presence of cats (OR = 1.6; 95% CI = 1.12–2.34). The seroprevalence observed in the present study indicates a widespread, although variable, exposure to T. gondii among domestic pigs in Spain, which might have important implications for public health. Management measures including control of rodents and cats on the farms could help to reduce the observed prevalence levels in Spain.  相似文献   

8.
《Médecine Nucléaire》2022,46(4):169-174
IntroductionWe applied the response to therapy reclassification system (RTRS) to evaluate the disease status after surgery and I-131 therapy in differentiated thyroid carcinoma (DTC) patients with nodular goiter (NG).Materials and methodsA total of 268 DTC complicated with NG patients who underwent the I-131 treatment and thyroidectomy between 2010 and 2018 were analyzed. The RTRS were classified into excellent (ER), indeterminate (IDR), biochemical incomplete (BIR) and structural incomplete response (SIR). Logistic regression analysis were performed to evaluate the relevant clinicopathologic and laboratory variables in the prediction of non-ER (IDR, BIR and SIR).ResultsIn the logistic analysis, gender (OR: 3.543, P = 0.01), lateral cervical lymph node metastases (N1b) (OR: 6.646, P = 0.005), pre-ablation stimulated thyroglobulin (Ps-Tg) (OR: 0.859, P = 0.000), and anti-Tg antibody (TgAb) (OR: 64.546, P = 0.000) were predictor of non-ER. The cut-off value of ps-Tg for predicting the ER was 19.98 ng/mL with a sensitivity of 92.6% and specificity of 83.2%. The non-ER rate of N1b group was significantly higher than the central cervical LNM (N1a) group.ConclusionFor patients with DTC complicated with NG, the cut-off value of ps-Tg for predicting the ER was 19.98 ng/mL. N1b patients showed inferior responses to I-131 therapy compared to N1a patients.  相似文献   

9.
《Theriogenology》2010,73(9):1221-1228
Cryopreservation of testicular sperm in the African clawed frog, Xenopus laevis, was tested using three penetrating cryoprotectants (DMSO, methanol, and glycerol) and three semen diluents (300 mmol/L glucose, 300 mmol/L sucrose, and a motility inhibiting saline [MIS] solution [150 mmol/L NaCl, 3 mmol/L KCL, 1 mmol/L Mg2SO4, 1 mmol/L CaCl2, and 20 mmol/L Tris, pH 8.0]). Three freezing rates and four thawing rates were also tested, and the best freezing/thawing conditions have been determined. The responses of sperm motility, viability, and fertility were assessed. Incubation of the sperm macerates with penetrating cryoprotectants showed that DMSO was the least toxic and methanol the most toxic. Semen in cryodiluents frozen 10 cm above the surface of liquid nitrogen (freezing rate of 20 to 25 °C/min) and thawed at room temperature for 40 sec had significantly higher percentages of motile and viable sperm than that of semen frozen 5 cm or 8 cm above the surface of liquid nitrogen and thawed at 5, 25, or 30 °C for 10, 15, or 60 sec, respectively. Sperm frozen in MIS containing 5% DMSO had a higher hatching rate than that of sperm frozen in sucrose and glucose diluents containing 5% or 10% DMSO and in MIS containing 10% DMSO. Addition of 73 mmol/L sucrose to the sperm extender MIS + 5% DMSO could improve the postthaw sperm motility and fertility. In conclusion, dilution of collected sperm in MIS solution (to have a final concentration of 6.5 × 106 to 8 × 106/mL) containing 5% DMSO and 73 mmol/L sucrose, freezing in a vapor of liquid nitrogen at 10 cm above the surface, and thawing at room temperature for 40 sec was the best cryopreservation protocol. This protocol gave 70% hatching rate, 80% motility rate, and 75% viability rate of fresh hormonally induced sperm.  相似文献   

10.
The knee kept forcibly in a flexed position is typical in cerebral palsy. Using a benchmark, we investigate intra-operatively if peak spastic hamstring force is measured in flexed knee positions. This tests the assumed shift of optimal length due to adaptation of spastic muscle and a decreasing force trend towards extension. Previously we measured spastic gracilis (GRA) and semitendinosus (ST) forces. Presently, we studied spastic semimembranosus (SM) and tested the following hypotheses: spastic SM forces are (1) high in flexed and (2) low in extended positions. We compared the data to those of GRA and ST to test (3) if percentages of peak force produced in flexed positions are different. During muscle lengthening surgery of 8 CP patients (9 years, 4 months; GMFCS levels = II–IV; limbs tested = 13) isometric SM forces were measured from flexion (120°) to full extension (0°). Spastic SM forces were low in flexed knee positions (only 4.2% (3.4%) and 10.7% (9.7%) of peak force at KA = 120° and KA = 90° respectively, indicating less force production compared to the GRA or ST) and high in extended knee positions (even 100% of peak force at KA = 0°). This indicates an absence of strong evidence for a shift of optimal muscle length of SM towards flexion.  相似文献   

11.
《Comptes rendus biologies》2014,337(7-8):466-473
The diet composition of the Grey Wagtail Motacilla cinerea of the Babor Range is followed by analysis of faecal samples (90 faeces) before and during the breeding season 2010. The Grey Wagtail's diet varies depending on the stage of the breeding cycle at the southern edge of their breeding area in North Africa (Bejaia). The diet consists predominantly of aquatic preys (51.79%), with Coleoptera being the most frequent constituent (n = 331, 45.5%). During the pre-laying period (February–March), the diet was variable (91 prey-taxa and H’ = 3,36 bits) and preys of medium size (5 to 8 mm) were most common. During the incubation period (April–May), preys were mainly aquatic (60%) and larger (20 to 32 mm). At the end of the breeding season (June–July), there was a greater occurrence of terrestrial preys (31 aquatic versus 30 terrestrial taxa).  相似文献   

12.
《Comptes Rendus Palevol》2019,18(6):663-684
The stratigraphical complex preserved at the site of Menez–Dregan I (Brittany, France) displays an alternating sequence of 17 occupation levels and of 4 marine deposits, between ca. 450 and 150,000 years (stratigraphical units 9a and 3b). The lithic industry retrieved at the site is extremely abundant, with more than 153,000 artefacts over 3 cm in length, as well as millions of knapping debris, and corresponds to a regional facies of the Acheulean, with heavy-duty tools essentially represented by choppers, as well as a few handaxes and cleavers. This paper presents a first synthesis of the data produced for almost 30 years on the site of Menez–Dregan I. The typological study of the entire lithic collection is now complete and allows us to assess the different human occupations that occurred at this site during the Lower Palaeolithic.  相似文献   

13.
Accomplishing reliable paleo-reconstructions of productivity and upwelling conditions in eastern boundary current systems requires the use of cores collected in a basin-wide spatial pattern. Based on diatom assemblage analysis and the concentration and the bulk biogenic components of three gravity cores recovered from the Benguela Upwelling System (BUS) between 19° and 25°S, I describe rapid paleoceanographic changes that occurred during the last 70 ka B.P. in the southeastern Atlantic. The pattern of biogenic production and accumulation differs to varying degrees among the three core sites along the SW African coast. The highest sedimentation and accumulation rates at 25°S off Lüderitz conform with the present-day, well-known pattern of highest productivity and most intense coastal upwelling. Highest diatom values at 25°S during MIS3 points to more intense upwelling due to the combination of strong seaward-extending upwelling filaments, shoaling of the upwelled water, and the influence of silicate-rich waters of Antarctic origin. Productivity decreased along the central BUS throughout MIS2, when the siliceous–calcareous productivity regime shifted toward a system dominated by calcareous producers. Although intensity and strength of winds created adequate conditions for upwelling during MIS2, diatom production decreased. The complete replacement of the upwelling-associated diatom flora by a non-upwelling-related diatom community during MIS1 reflects weakened upwelling, weakened seaward extension of the upwelling filaments, and dominance of warmer surface waters. Combining changes in the composition of the diatom assemblage and variations of the bulk biogenic components allows for reliable reconstruction of paleoproductivity and upwelling changes for the SE Atlantic during the last 70 ka B.P.  相似文献   

14.
Blastocystis sp. is a common gut-dwelling protist of both humans and animals. A cross-sectional survey among humans and their dogs was conducted to determine the prevalence of Blastocystis infection and to characterize the subtype (ST) distribution in an urban community in the Philippines. Fecal specimens from 1,271 humans and 145 dogs were collected and inoculated in diphasic culture medium. Prevalence of Blastocystis by culture was 13.0% (95% CI = 11.2–15.0) and 14.5% (95% CI = 9.6–21.2) for humans and dogs, respectively. A total of 168 culture isolates were genotyped using polymerase chain reaction (PCR) with seven pairs of ST-specific sequence-tagged-site (STS) primers. In humans, the ST present in this study were ST1 with 22.6% (95% CI = 17.2–29.0), ST2 with 3.1% (95% CI = 1.3–6.7), ST3 with 41.4% (95% CI = 34.9–48.6), ST4 with 14.8% (95% CI = 10.5–20.6), ST5 with 4.1% (95% CI = 2.0–8.0), and unknown ST with 13.9% (95% CI = 9.6–19.4). In dogs, the ST present in this study were ST1 with 4.3% (95% CI = 0.0–29.0), ST2 with 8.7% (95% CI = 1.3–28.0), ST3 with 17.4% (95% CI = 6.4–37.7), ST4 with 13.0% (95% CI = 3.7–33.0), ST5 with 13.0% (95% CI = 3.7–33.0), and unknown ST with 47.8% (95% CI = 29.2–67.0). This is the first study that reported Blastocystis ST4 in human and canine hosts in the Philippines.  相似文献   

15.
《Ecological Indicators》2007,7(3):521-540
Benthic, epiphytic, and phytoplanktonic diatoms, as well as soil and water physical–chemical parameters, were sampled from 70 small (average 0.86 ha) isolated depressional herbaceous wetlands located along a gradient of human disturbance in peninsular Florida to (1) compare diatom assemblage structure between algal types; (2) develop biological indicators of wetland condition; (3) examine synecological relationships between diatom structure and environmental variables, with the ultimate goal of developing an index of biological integrity using a single assemblage. Collected diatom samples were enumerated to 250 valves and identified to species or subspecies. An assessment of wetland condition was made using a landscape-scale human disturbance score (Landscape Development Intensity index, LDI), calculated for each site using land use maps and GIS.Assemblages from both impaired and reference sites were compared using blocked multi-response permutation procedures, the percent similarity index, and visually examined using non-metric multidimensional scaling (NMDS). No ecologically significant compositional differences were found within sites. Mantel's test (Mantel's r = 0.29, p < 0.0001) and NMDS (stress: 14.52, variance: 78.5%) identified epiphytic diatoms as the most responsive to human disturbance. Strong significant correlations (|rs| > 0.50, p < 0.05) were found between epiphytic NMDS site scores and soil pH, specific conductivity, water total phosphorous, and LDI, while soil pH, water color, soil TP, and turbidity were also significantly correlated (p < 0.05).Metrics to assess wetland condition were developed using epiphytic abundance data. Epiphytic taxa sensitive or tolerant to human landscape modification were identified using Indicator Species Analysis, and autecological indices relating diatom sensitivity to nutrients, pH, dissolved oxygen levels, saprobity, salinity, and trophic status were calculated. Fourteen final metrics were identified, scored on an ordinal scale, and combined into the Diatom Index of Wetland Condition (DIWC). The DIWC was highly correlated with the disturbance score (Spearman's rs = −0.71, p < 0.0001), although the results need to be validated.  相似文献   

16.
Large quantities of free protein in the environment and other bioaerosols are ubiquitous throughout terrestrial ground level environments and may be integrative indicators of ecosystem status. Samples of ground level bioaerosols were collected from various ecosystems throughout Ecuador, including pristine humid tropical forest (pristine), highly altered secondary humid tropical forest (highly altered), secondary transitional very humid forest (regrowth transitional), and suburban dry montane deforested (suburban deforested). The results explored the sensitivity of localized aerosol protein concentrations to spatial and temporal variations within ecosystems, and their value for assessing environmental change. Ecosystem specific variations in environmental protein concentrations were observed: pristine 0.32 ± 0.09 μg/m3, highly altered 0.07 ± 0.05 μg/m3, regrowth transitional 0.17 ± 0.06 μg/m3, and suburban deforested 0.09 ± 0.04 μg/m3. Additionally, comparisons of intra-environmental differences in seasonal/daily weather (dry season 0.08 ± 0.03 μg/m3 and wet season 0.10 ± 0.04 μg/m3), environmental fragmentation (buffered 0.19 ± 0.06 μg/m3 and edge 0.15 ± 0.06 μg/m3), and sampling height (ground level 0.32 ± 0.09 μg/m3 and 10 m 0.24 ± 0.04 μg/m3) demonstrated the sensitivity of protein concentrations to environmental conditions. Local protein concentrations in altered environments correlated well with satellite-based spectral indices describing vegetation productivity: normalized difference vegetation index (NDVI) (r2 = 0.801), net primary production (NPP) (r2 = 0.827), leaf area index (LAI) (r2 = 0.410). Moreover, protein concentrations distinguished the pristine site, which was not differentiated in spectral indices, potentially due to spectral saturation typical of highly vegetated environments. Bioaerosol concentrations represent an inexpensive method to increase understanding of environmental changes, especially in densely vegetated ecosystems with high canopies or in areas needing high spatial and temporal resolution. Further research to expand understanding of the applicability of bioaerosol concentrations for environmental monitoring is supported by this pilot study.  相似文献   

17.
We quantified the thermal inhibitory effect of 71 °C (recommended for cooking ground meats), and re-heating at 85 °C, on food- and food-animal-derived Clostridium difficile spores. All C. difficile strains tested (n = 20) survived 71 °C for 2 h, but 90% died within 10 min when re-heated at 85 °C. Current cooking recommendations would need revision to include C. difficile.  相似文献   

18.
Miocene scleractinian corals were documented for the first time in the Fırat Formation of Sarıca village, Eğil district of Diyarbakır, SE Turkey. The fauna consists of four hermatypic species belonging to three families: Diploastrea taurinensis (d’Achiardi, 1868), Tarbellastraea reussiana (Milne-Edwards and Haime, 1850), Echinopora gemmacea (Lamarck, 1816) and Montastraea pelouaensis (Chevalier, 1954). The morphospecies described here are typical of the early Miocene (Aquitanian-Burdigalian) and show that the Fırat Formation coral community was composed of shallow and subtropical reefs of Mediterranean Tethys palaeobiogeographical affinity. The examined species are reef components found in tropical and subtropical oceans, as are the majority of zooxanthellae. The species were upper photic zone related, had massive colonial growth morphology, and lived in a shallow tropical-subtropical marine palaeoenvironment at a depth of up to 50 m. They grew on hard ground, clean water, and normal salinity and required a minimum seawater temperature of 18 ̊C; however, they were most abundant at water temperatures ranging from 22 to 26 ̊C in high-moderate water energy. Consequently, this fossil assemblage will not only improve our knowledge of scleractinian coral diversity and morphological variation in SE Turkey but will also provide an important background for future studies of coral taxonomy, diversity and biogeography of the region.  相似文献   

19.
The lipase from Bacillus subtillus (BSL2), a highly active lipase expressed from newly constructed strain of Bacillus subtilis BSL2, is used in the kinetic resolution of glycidyl butyrate. A high enantiomeric ratio (E = 108) was obtained by using 1,4-dioxane as co-solvent (18%, v/v) and decreasing the reaction temperature to 5 °C. The ratio is about 16-fold more than that (E = 6.52) obtained in pure buffer solutions (25 °C, pH 7.8). Under the optimum conditions, the remained (R)-glycidyl butyrate with high enantiopure (ee > 98%) was obtained when the conversion was above 52%.  相似文献   

20.
The purpose of this study was to examine whether muscle architecture of the long head of biceps femoris (BF) and semitendinosus (ST) muscles varies along their length. The ST and BF muscles were dissected and removed from their origins in eight cadaveric specimens (age range 67.8–73.4 years). One-way analysis of variance designs were used to compare fascicle length (FL), pennation angle (PA) and muscle thickness (MT) between proximal, mid-belly and distal positions. Tendon and muscle length properties were also quantified. For the BF muscle, one-way analysis of variance tests showed a higher PA (23.96 ± 3.82°) and FL (7.12 ± 0.48 cm) proximally than distal positions (PA = 17.78 ± 1.95° and FL = 6.35 ± 0.89 cm, respectively). For the ST, there was a significantly (p < 0.05) lower PA (8.81 ± 1.22°) and FL (13.10 ± 1.54 cm) proximally than distally (PA = 14.69 ± 1.09° and FL = 15.49 ± 2.30 cm, respectively). Muscle thickness significantly increased from distal to more proximal positions (p < 0.05). These data suggest that the ST and BF architecture is not uniform and that measurement of these parameters largely depends on the measurement site. Modeling these muscles by assuming a uniform architecture along muscle length may yield less accurate representation of human hamstring muscle function.  相似文献   

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