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1.
Physical size has been critical in the evolutionary success of the genus Homo over the past 2.4 million-years. An acceleration in the expansion of savannah grasslands in Africa from 1.6 Ma to 1.2 Ma witnessed concomitant increases in physical stature (150–170 cm), weight (50–70 kg), and brain size (750–900 cm3). With the onset of 100,000 year Middle Pleistocene glacial cycles (“ice ages”) some 780,000 years ago, large-bodied Homo groups had reached modern size and had successfully dispersed from equatorial Africa, Central, and Southeast Asia to high-latitude localities in Atlantic Europe and North East Asia. While there is support for incursions of multiple Homo lineages to West Asia and Continental Europe at this time, data does not favour a persistence of Homo erectus beyond ~400,000 years ago in Africa, west and Central Asia, and Europe. Novel Middle Pleistocene Homo forms (780,000–400,000 years) may not have been substantially taller (150–170 cm) than earlier Homo (1.6 Ma–800,000 years), yet brain size exceeded 1000 cm3 and body mass approached 80 kg in some males. Later Pleistocene Homo (400,000–138,000 years) were ‘massive’ in their height (160–190 cm) and mass (70–90 kg) and consistently exceed recent humans. Relative brain size exceeds earlier Homo, yet is substantially lower than in final glacial H. sapiens and Homo neanderthalensis. A final leap in absolute and relative brain size in Homo (300,000–138,000 years) occurred independent of any observed increase in body mass and implies a different selective mediator to that operating on brain size increases observed in earlier Homo.  相似文献   

2.
BackgroundGastric cancer is the fourth most common cancer in the world. Environmental and genetic factors both play critical roles in the etiology of gastric cancer. Hundreds of SNPs have been identified to have association with the risk of gastric cancer in many races. In this study, 25 SNPs in genes for IL-10, IL-1B, MTRR, TNF-а, PSCA, PLCE1 and NOC3L were analyzed to further evaluate their associations with gastric cancer susceptibility in the Chinese Han population.MethodsTwo hundred and seventy nine gastric cancer patients and 296 healthy controls were recruited in this study. SNP genotyping was conducted using Sequenom MassARRAY RS1000. Data management and statistical analyses were conducted by Sequenom Typer 4.0 Software and Pearson's χ2 test.ResultsOne protective allele and three risk alleles for gastric cancer patients were found in this study. The allele “G” of rs1801394 in MTRR showed an association with a decreased risk of gastric cancer: odds ratio (OR) = 0.74, 95% confidence interval (95% CI) = 0.57–0.97, P = 0.030 in the additive model; OR = 0.495, 95% CI = 0.26–0.95, P = 0.034 in the recessive model. The other three SNPs, the allele “C” of rs1800871 in IL10 (OR = 1.33, 95% CI = 1.04–1.90; P = 0.026 in the additive model; OR = 1.46, 95% CI = 1.04–2.06; P = 0.030 in the recessive model), the allele “A” of rs2976391 in PSCA (OR = 1.30, 95% CI = 1.01–1.66; P = 0.041 in the additive model and OR = 1.48, 95% CI = 1.04–2.11, P = 0.028 in the recessive model), and the allele “G” of rs17109928 in NOC3L gene (OR = 1.34, 95% CI = 1.01–1.78; P = 0.042 by additive model analysis; OR = 1.47, 95% CI = 1.04–2.07, P = 0.028 by dominant model analysis), showed an association with an increased risk of gastric cancer.ConclusionsThese results indicate the importance of four gastric cancer susceptibility polymorphisms of IL-10, NOC3L, PSCA and MTRR in the Chinese Han population, which could be used in the determination of gastric cancer risk in clinical practice.  相似文献   

3.
Man made ecosystems of dry lands are key habitats due to their ecological characteristics to survey biodiversity. This study investigated bird diversity in three oases of the Northern Algerian Sahara (i.e., Biskra in 2006, Oued Souf in 2008 and Ouargla in 2009), by using the spot-mapping method. Bird density “D” (pairs/10 ha), species richness “S” (number species), diversity (Shannon index) “H′” (in bits), and evenness “E” varied from one oasis to another (Biskra: D = 98.5, S = 47, H′ = 4.49, E = 0.81; Oued Souf: D = 96, S = 33, H′ = 3.9, E = 0.77; Ouargla: D = 91.5, S = 44, H′ = 4.39, E = 0.80). Differences in bird diversity between the monitored palm groves are due to the ecological characteristics of each environment. Documented literature outlined close taxonomic similarities between bird assemblages of the study area with many Northern Saharan oases. The Hybrid Sparrow Passer domesticus x Passer. hispaniolensis and some Columbidae species including Columba livia, Streptopelia turtur, Streptopelia senegalensis, and Streptopelia decaocto were the abundant species throughout surveyed oases in which they represented more than half (55.6%) of the sum of species densities (D = 286 pairs/10 ha). These synthropic species have known a huge expansion of their distribution range throughout Algerian oases. The correspondence analysis allowed the aggregation of both families and species into oasis they belong to. One-way ANOVA was tested to analyse variations of both family and species densities between studied oases. The ANOVA revealed there was no significant variation either in family densities (p = 0.937) or in bird densities (p = 0.622) between the surveyed oases because of the small size of bird populations.  相似文献   

4.
《农业工程》2014,34(1):53-65
Soil water resource, together with the surface and sub-surface water resource, is essential to the regional water balance and world water cycle. A total of 90 soil samples were collected from 30 different soil profiles of dry fields throughout Chongqing, China randomly to show how soil could be a crucial part of water resources by discussing their five types of calculated soil water reservoir capacities, namely the total soil water reservoir capacity (mm) (TC), soil water storage capacity (mm) (SC), unavailable soil water reservoir capacity (mm) (UC), available soil water reservoir capacity (mm) (AC), and soil dead water storage capacity (mm) (DC) in certain layer, respectively. Overall, the total soil water reservoir capacity in 0–40 cm was about 209 mm, of which 70 mm belonged to available soil water reservoir capacity. Not all the five types of soil water reservoir capacities had significant correlations between each other. Soil structure, especially the size and quantity of soil pore was mainly determined by soil particle composition (clay, silt, and sand content). The more sand and less clay led to the more soil macropores, which provided room for soil water. Thus, clay, silt, and sand content jointly produced profound influence on soil water reservoir capacities. Nevertheless, specific water capacity and topographic factors displayed weak correlations to soil water reservoir capacities, which required further research works. Ultimately, the better regression models were achieved by multiple regression analysis coupled with “merged groups PCA” than by multiple regression analysis with “all variables PCA”. UC, SC, TC and DC could be well simulated (mostly R2 > 0.70; P < 0.05) through normal multiple regression analysis using original variables as well as multiple regression analysis with “merged groups PCA”. Only regression models of TC and DC were highly significant (mostly R2 > 0.70; P < 0.05) through “all variables PCA” method. And there were poor coefficients of determination (R2) for AC (mostly R2 < 0.40; P < 0.05) by all the three regression methods.  相似文献   

5.
The abdominal muscle activity has been shown to be variable in subjects with chronic obstructive pulmonary disease (COPD) when respiratory demand increases and their recruitment pattern may change the mechanics, as well as the work and cost of breathing. The scientific evidence in subjects “at risk” for the development of COPD may be important to understand the natural history of this disease. This study aims to evaluate the effect of inspiratory and expiratory loads on the abdominal muscle activity during breathing in subjects “at risk” for the development of COPD and healthy. Thirty-one volunteers, divided in “At Risk” for COPD (n = 17; 47.71 ± 5.11 years) and Healthy (n = 14; 48.21 ± 6.87 years) groups, breathed at the same rhythm without load and with 10% of the maximal inspiratory or expiratory pressures, in standing. Surface electromyography was performed to assess the activation intensity of rectus abdominis (RA), external oblique and transversus abdominis/internal oblique (TrA/IO) muscles, during inspiration and expiration. During inspiration, in “At Risk” for COPD group, RA muscle activation was higher with loaded expiration (p = 0.016); however, in Healthy group it was observed a higher activation of external oblique and TrA/IO muscles (p < 0.050). During expiration, while in “At Risk” for COPD group, RA muscle activation was higher with loaded inspiration (p = 0.009), in Healthy group TrA/IO muscle showed a higher activation (p = 0.025). Subjects “at risk” for the development of COPD seemed to have a specific recruitment of the superficial layer of ventrolateral abdominal wall for the mechanics of breathing.  相似文献   

6.
The purpose of this study is to measure patient skin dose in tangential breast radiotherapy. Treatment planning dose calculation algorithm such as Pencil Beam Convolution (PBC) and in vivo dosimetry techniques such as radiochromic film can be used to accurately monitor radiation doses at tissue depths, but they are inaccurate for skin dose measurement. A MOSFET-based (MOSkin) detector was used to measure skin dose in this study. Tangential breast radiotherapies (“bolus” and “no bolus”) were simulated on an anthropomorphic phantom and the skin doses were measured. Skin doses were also measured in 13 patients undergoing each of the techniques. In the patient study, the EBT2 measurements and PBC calculation tended to over-estimate the skin dose compared with the MOSkin detector (p < 0.05) in the “no bolus radiotherapy”. No significant differences were observed in the “bolus radiotherapy” (p > 0.05). The results from patients were similar to that of the phantom study. This shows that the EBT2 measurement and PBC calculation, while able to predict accurate doses at tissue depths, are inaccurate in predicting doses at build-up regions. The clinical application of the MOSkin detectors showed that the average total skin doses received by patients were 1662 ± 129 cGy (medial) and 1893 ± 199 cGy (lateral) during “no bolus radiotherapy”. The average total skin doses were 4030 ± 72 cGy (medial) and 4004 ± 91 cGy (lateral) for “bolus radiotherapy”. In some cases, patient skin doses were shown to exceed the dose toxicity level for skin erythema. Hence, a suitable device for in vivo dosimetry is necessary to accurately determine skin dose.  相似文献   

7.
The objective of this study was to compare reaction time, joint torque, rate of torque development, and magnitude of neuromuscular activation of lower-extremity muscles in elderly female fallers and nonfallers. Participants included 11, elderly, female fallers (71.3 ± 5.4 years) and twelve nonfallers (71.3 ± 6.2 years) who completed a fall risk questionnaire. Then, maximal, voluntary, isometric contractions of the knee and ankle muscles were performed in reaction to a visual cue to determine joint torque, rate of torque development, reaction time, and nervous activation of agonists and antagonists. Results indicated that significantly more fallers reported “dizziness upon rising”, “use of balance altering medications”, “stress or depression”, “not enough sleep”, “arthritis in lower body”, “chronic pain in lower body”, and “tiring easily while walking” (all P < 0.05). Normalized dorsiflexion and plantarflexion strength scores (summation of peak torque, rate of torque development and impulse) were lower in fallers than in nonfallers (P < 0.05). When summed across lower-extremity muscle groups, fallers demonstrated 19% lower peak torque and 29% longer motor time (P < 0.05). In conclusion, comprehensive fall risk screening and prevention programs should address both neuromuscular and non-muscular factors, and, weakness of the ankle dorsiflexors and plantarflexors should be further studied as potential contributors to falls in older adults.  相似文献   

8.
The purpose of this study is to explore the main correlates of male height in 105 countries in Europe & overseas, Asia, North Africa and Oceania. Actual data on male height are compared with the average consumption of 28 protein sources (FAOSTAT, 1993–2009) and seven socioeconomic indicators (according to the World Bank, the CIA World Factbook and the United Nations). This comparison identified three fundamental types of diets based on rice, wheat and milk, respectively. The consumption of rice dominates in tropical Asia, where it is accompanied by very low total protein and energy intake, and one of the shortest statures in the world (∼162–168 cm). Wheat prevails in Muslim countries in North Africa and the Near East, which is where we also observe the highest plant protein consumption in the world and moderately tall statures that do not exceed 174 cm. In taller nations, the intake of protein and energy no longer fundamentally rises, but the consumption of plant proteins markedly decreases at the expense of animal proteins, especially those from dairy. Their highest consumption rates can be found in Northern and Central Europe, with the global peak of male height in the Netherlands (184 cm). In general, when only the complete data from 72 countries were considered, the consumption of protein from the five most correlated foods (r = 0.85) and the human development index (r = 0.84) are most strongly associated with tall statures. A notable finding is the low consumption of the most correlated proteins in Muslim oil superpowers and highly developed countries of East Asia, which could explain their lagging behind Europe in terms of physical stature.  相似文献   

9.
The structure of Panicum Mosaic Virus (PMV) was determined by X-ray diffraction analysis to 2.9 Å resolution. The crystals were of pseudo symmetry F23; the true crystallographic unit cell was of space group P21 with a = 411.7 Å, b = 403.9 Å and c = 412.5 Å, with β = 89.7°. The asymmetric unit was two entire T = 3 virus particles, or 360 protein subunits. The structure was solved by conventional molecular replacement from two distant homologues, Cocksfoot Mottle Virus (CfMV) and Tobacco Necrosis Virus (TNV), of ~20% sequence identity followed by phase extension. The model was initially refined with exact icosahedral constraints and then with icosahedral restraints. The virus has Ca++ ions octahedrally coordinated by six aspartic acid residues on quasi threefold axes, which is completely different than for either CfMV or TNV. Amino terminal residues 1–53, 1–49 and 1–21 of the A, B and C subunits, respectively, and the four C-terminal residues (239–242) are not visible in electron density maps. The additional ordered residues of the C chain form a prominent “arm” that intertwines with symmetry equivalent “arms” at icosahedral threefold axes, as was seen in both CfMV and TNV. A 17 nucleotide hairpin segment of genomic RNA is icosahedrally ordered and bound at 60 equivalent sites at quasi twofold A–B subunit interfaces at the interior surface of the capsid. This segment of RNA may serve as a conformational switch for coat protein subunits, as has been proposed for similar RNA segments in other viruses.  相似文献   

10.
The purpose of the work was to provide a crystallographic demonstration of the venerable idea that CO photolyzed from ferrous heme-a3 moves to the nearby cuprous ion in the cytochrome c oxidases. Crystal structures of CO-bound cytochrome ba3-oxidase from Thermus thermophilus, determined at ~ 2.8–3.2 Å resolution, reveal a Fe–C distance of ~ 2.0 Å, a Cu–O distance of 2.4 Å and a Fe–C–O angle of ~ 126°. Upon photodissociation at 100 K, X-ray structures indicate loss of Fea3–CO and appearance of CuB–CO having a Cu–C distance of ~ 1.9 Å and an O–Fe distance of ~ 2.3 Å. Absolute FTIR spectra recorded from single crystals of reduced ba3–CO that had not been exposed to X-ray radiation, showed several peaks around 1975 cm? 1; after photolysis at 100 K, the absolute FTIR spectra also showed a significant peak at 2050 cm? 1. Analysis of the ‘light’ minus ‘dark’ difference spectra showed four very sharp CO stretching bands at 1970 cm? 1, 1977 cm? 1, 1981 cm? 1, and 1985 cm? 1, previously assigned to the Fea3–CO complex, and a significantly broader CO stretching band centered at ~ 2050 cm? 1, previously assigned to the CO stretching frequency of CuB bound CO. As expected for light propagating along the tetragonal axis of the P43212 space group, the single crystal spectra exhibit negligible dichroism. Absolute FTIR spectrometry of a CO-laden ba3 crystal, exposed to an amount of X-ray radiation required to obtain structural data sets before FTIR characterization, showed a significant signal due to photogenerated CO2 at 2337 cm? 1 and one from traces of CO at 2133 cm? 1; while bands associated with CO bound to either Fea3 or to CuB in “light” minus “dark” FTIR difference spectra shifted and broadened in response to X-ray exposure. In spite of considerable radiation damage to the crystals, both X-ray analysis at 2.8 and 3.2 Å and FTIR spectra support the long-held position that photolysis of Fea3–CO in cytochrome c oxidases leads to significant trapping of the CO on the CuB atom; Fea3 and CuB ligation, at the resolutions reported here, are otherwise unaltered. This article is part of a Special Issue entitled: Respiratory Oxidases.  相似文献   

11.
We devised a probability distribution model that best expressed species richness per quadrat in grassland communities, and clarified the mechanism by which the mean richness per quadrat was always larger than the variance among quadrats. Our model will aid in the understanding of community structures, and allow comparisons among different communities. The model was constructed based on relatively simple theoretical assumptions about the mechanisms in play in target communities. We assumed in the model that the number of species occurring in an actual quadrat, j, is the sum of “the fundamental number of species”, k (constant), and “a fluctuating number of species”, i (a Poisson variate with the mean of μ); that is, j = k + i, where i, j and k are non-negative integers. The probability that j species occur in a quadrat is given by a Poisson-like distribution (extended Poisson), with two parameters k and μ. The mean species richness in the probability distribution is expressed by λ (= k + μ), and the variance is λ  k. The proposed model afforded a good fit for the observed frequency distribution of species richness per quadrat. If even one species is common among many quadrats, the mean number of species per quadrat is greater than the variance. The greater the number of common species among quadrats is, the larger is the value of k, and then the more pronounced is the difference between the mean and the variance (although the variance does not change). We fitted the model to 55 datasets collected by ourselves from grasslands in various locations (Tibet, Inner Mongolia, Slovakia, or Japan), with varying quadrat size (0.25, 0.0625, or 0.01 m2), and under differing management status (various stocking densities).  相似文献   

12.
Biomonitoring by means of the supersensitive cultivar Nicotiana tabacum Bel-W3 is frequently used to obtain information on ozone effects on plants and estimates of ozone exposure. However, most of biomonitoring surveys do not account for other environmental variables (predictors in a statistical model) and their inherent multicollinearity with ozone. We tested the relative role of different predictors (fixed: time and site; random: ozone, temperature and humidity) on height growth and on the development of visible foliar symptoms of N. tabacum Bel-W3 plants. To do this, we investigated a relatively small area (256 km2), used a random design at every stage of the survey, controlled watering and protected plants from direct solar radiation and wind. QA/QC procedures were adopted at every stage of the investigation. Linear correlation shows that Leaf Injury Index (LII) and height increment (H.I.) positively related to ozone concentration, elevation and temperature, and negatively to relative humidity. All the predictors correlate to each other. However, relationships between response and ozone vary with the site and the monitoring week. The effect of the random factor “ozone” in combination with fixed factors “site” and “time” on the response variables was therefore formally investigated using the ANCOVA model. Besides ozone, the interactions “ozone × site” and “ozone × time” resulted always significant (0.001 < P < 0.05). While the factor “time” emphasize the inherent development of injury and growth through time, the interaction “ozone × site” pointed out the importance of local conditions. When watering, solar radiation, wind and plant characteristics were controlled, the remaining site-specific covariates of interest were temperature (T) and humidity (RH). When T and RH were accounted for by means of partial correlation analysis, no significant relationship was found between ozone and LII. On the other side, O3 and RH resulted significant for both absolute and relative height increment. In short, LII seemed to be not solely dependent on ozone, T and RH, but showed to integrate their combined effect. On the other side, H.I. seemed to be favoured by high RH and T, and depressed by high ozone. Based on the above results, we recommend caution when handling bioindicator data: if the purpose is to infer ozone concentrations by leaf injury data, results may be affected by a serious bias, as the frequently reported correlations may be partly an artefact due to co-variation between predictors.  相似文献   

13.
Two new ursane-type triterpene saponins, 3-O-β-d-glucopyranosyl(1  3)-[α-l-rhamnopyranosyl(1  2)]-α-l-arabinopyranosylurs-12,19(29)-dien-28-oic acid 28-O-α-l-rhamnopyranosyl(1  2)-β-d-glucopyranosyl ester (1) and 3-O-β-d-glucopyranosyl(1  3)-[α-l-rhamnopyranosyl(1  2)]-α-l-arabinopyranosyl-19α,20α-dihydroxyurs-12-en-28-oic acid 28-O-α-l-rhamnopyranosyl(1  2)-β-d-glucopyranosyl ester (2), along with thirteen known triterpene saponins were isolated from the n-BuOH part of the MeOH extraction of the leaves of Ilex kudingcha C.J. Tseng (also called “Ku-Ding-Cha”). The structures of new compounds were elucidated on the basis of detailed spectroscopic analysis, including HR-ESI-TOF-MS, 1D and 2D-NMR experiments, and by acid hydrolysis. All the compounds were screened for antiplatelet aggregation activity in vitro, and compounds 1, 2, 3, 7, 12 and 15 showed significant inhibition of platelet aggregation induced by ADP (5 μM) with IC50 values of 14.7 ± 3.7, 11.3 ± 2.5, 17.4 ± 4.6, 20.5 ± 3.1, 8.1 ± 1.5 and 18.9 ± 4.2 μM, respectively.  相似文献   

14.
《Médecine Nucléaire》2020,44(3):203-212
IntroductionThe kidney is considered as a critical dose-limiting organ with 177Lu-Dotatate. Renal dosimetry could play a role in optimizing treatment. We present a feedback on the implementation of renal dosimetry in our medical center.Material and methodThe renal dosimetry of the 1st administration of 177Lu-Dotatate (approximately 7.4 GBq) has been performed for seven patients. The reference dosimetry strategy included 4 post-therapeutic SPECT/CT at 6 h, 24 h, 72 h and 168 h and anatomical renal volume delineation (VOI). Alternative dosimetric strategies consisted of 72 h or 168 h time point eviction (time sampling A or B) and delimitation of 1 or 3 spherical VOIs (3 mL each) per kidney (“1 sVOI” or “3 sVOI” methods). The quantitative scintigraphic processing was performed by 4 operators using Dosimetry Toolkit®. The renal dose was calculated with OLINDA/EXM® 2.0.ResultsThe calculated mean absorbed renal dose was 3.68 ± 0.68 Gy with the reference method, with no significant impact of interoperator variability (P = 0.41). It was in satisfactory agreement with time sampling A or B. The “1 sVOI” and “3 sVOI” methods overestimated the renal dose (5.01 ± 0.94 Gy and 4.91 ± 0.79 Gy respectively), with a significant impact on interoperator variability (P < 0.05), despite a reduction in processing time.ConclusionThe main logistic constraint of 177Lu-Dotatate renal dosimetry in our center is the time-consumption due to SPECT/CT acquisitions. A possible approach supported by our preliminary results is a reduction in the number of scintigraphic acquisitions.  相似文献   

15.
Warneckea populations from “sand-forest” or “sand-thicket” habitats in Tembe Elephant Park, South Africa, and Licuati Forest Reserve in adjacent southern Mozambique were previously thought to be a small-leaved form of W. sousae, which typically includes larger-leaved plants ranging from central Mozambique northward to Tanzania. We examine this hypothesis using molecular and morphological evidence. Maximum-likelihood phylogenetic analysis of combined nrDNA ETS and ITS sequence data failed to resolve W. sousae and the Maputaland populations as an exclusively monophyletic group. Instead, the Kenyan endemic W. mouririifolia was strongly supported as the sister species of W. sousae, and the Maputaland plants were resolved in a separate, strongly supported clade together with populations of an as-yet undetermined Warneckea species from northern Mozambique. A hypothesis of exclusive monophyly for the plants from Tembe and Licuati had moderate support in separate ETS and ITS1 analyses (bootstrap proportions of 88% and 81%, respectively). Statistically significant differences in leaf dimensions and internode length were found between the Maputaland plants and typical W. sousae. We conclude that the populations from Tembe and Licuati represent a distinct species, which we describe as W. parvifolia. The species differs from W. sousae in having shorter internodes (mostly 5–25 mm not 10–60 mm long), smaller leaves (mostly 14–32 × 8–19 mm not 40–76 × 22–52 mm), shorter petioles (mostly 1–1.5 mm not 1.5–6 mm long), smaller flowers (hypanthium 1 × 1.5–1.75 mm not 1.5–2 × 2 mm; calyx lobes 0.5 mm not 0.75 mm long; staminal filaments 3–4 mm not 5 mm long; style 4–5 mm not 9 mm long), and globose fruit (not obovoid). An IUCN conservation status of Endangered (EN) B1a, b(ii, iii) is indicated for W. parvifolia, due to its limited distribution and projected declines in its habitat quality and area of occupancy.  相似文献   

16.
《Aquatic Botany》2005,81(1):1-11
Seed bank samples were collected from Huli Marsh, a subtropical shallow water mountainous marsh in Hunan Province, South China. Core samples were divided into upper and lower layers (each 5 cm in depth) and allowed to germinate in three water levels (0, 5 and 10 cm) over a 4-month period. A total of 51 species germinated and the mean density was 9211 ± 7188 seedlings m−2. In the top 5 cm 41 species and 5747 ± 5111 seedlings m−2 germinated, whereas 40 species and 3464 ± 3363 seedlings m−2 did so from 5–10 cm. Germinated seedling density was significantly higher in the upper layer, largely due to differences in eight species. With increasing experimental water depth, less seedlings germinated: respectively, 9788 ± 7157 m−2, 2050 ± 2412 m−2 and 1978 ± 2616 m−2, of 44, 21 and 19 species, submerged under 0, 5 or 10 cm. Seven species could emerge only in 0 water level. Vallisneria natans occurred only in 5 cm water, whereas Ottelia alismoides occurred in 10 cm water. In the vegetation survey of the marsh, 25 species were recorded, which was less than half of the species recorded in the seed bank. The top 10 dominants in the standing vegetation, accounting for 89% of vegetation abundance, represented only 10% in the seed bank. Twenty germinated species that also occurred in the standing vegetation accounted for 56% of the total seed bank. Our observed number of species germinating from a Chinese wetland seed bank is within the range observed elsewhere in the northern hemisphere (15–113 species).  相似文献   

17.
《Small Ruminant Research》2010,91(1-3):11-17
Isoelectric focusing (IEF) was applied for screening milk protein variants in milk samples from altogether 1078 sheep of different breeds, in detail Black Faced Mutton sheep (SKF; n = 57), East Friesian Milk sheep (OMS; n = 254), Gray Horned Heath (GGH; n = 190), Merinoland sheep (MLS; n = 363), Merino Mutton sheep (MMS; n = 88), and Rhön sheep (RHO; n = 126). Besides the known genetic variants of αs1-casein (CSN1S1) (A, C, D), αs2-casein (CSN1S2) (A, B), and β-lactoglobulin (LGB) (A, B, C) additional variants could be demonstrated in CSN1S1 (H, I) and CSN1S2 (C, D) and their genetic control confirmed by segregation analyses. CSN1S1*H corresponds to a previously mentioned phenotype “X” occurring in OMS, whereas CSN1S1*I was identified for the first time in GGH. CSN1S2*C appeared in OMS, GGH, MLS, and RHO in low frequencies and CSN1S2*D in MLS. Within LGB all three alleles occurred in Merino breeds while α-lactalbumin (LAA) and κ-CN (CSN3) were monomorph at protein level. The haplotype CSN1S1*CCSN1S2*A was predominant in five out of six breeds with frequencies between 0.325 and 0.919.  相似文献   

18.
《Phytomedicine》2014,21(3):277-281
Senna spectabilis (sin. Cassia excelsa, C. spectabilis) is an endemic tree of South America and Africa, very common in Brazil, where it is known as “canafistula-de-besouro” and “cassia-do-nordeste”. In folk medicine, this plant is indicated for the treatment of constipation, insomnia, anxiety, epilepsy, malaria, dysentery and headache. Phytopharmacological studies have also confirmed anticonvulsive, sedative, anti-malarial, antimicrobial and cytotoxic properties of many parts of S. spectabilis. In this communication, we present a comparative study of the leishmanicidal activity of the crude ethanolic extract, its fractions and also the two major alkaloidal metabolites (−)-cassine/(−)-spectaline, trying to establish a relationship between the presence of piperidine alkaloidal constituents and leishmanicidal activity. The growth inhibitory effect of promastigote forms of Leishmania major was determined for the crude extract, fractions of the flowers of S. spectabilis and a mixture of (−)-cassine/(−)-spectaline in comparison to pentamidine used as standard drug. The cytotoxic effects were assessed on macrophage strain J774 by lactate dehydrogenase assay. Fractions dichloromethane (FL-DCM) and n-butanol (FL-Bu) and a mixture of (−)-cassine/(−)-spectaline (∼7:3) exhibited significant activity against the parasite Leishmania major (IC50 values of 0.6 ± 0.1 μg/ml, 1.6 ± 0.9 μg/ml and 24.9 ± 1.4 μg/ml, respectively), without toxic effects on murine macrophages. Due to the promising results elicited, further studies in vivo need to be performed to confirm the therapeutic potential of Senna spectabilis.  相似文献   

19.
We analyzed the evolution of height in Colombia of cohorts born in the period 1965–1990 by ethnic groups. We found that Afro-Colombian men and women were the tallest: 6 cm taller than indigenous people and 2 cm taller than the rest of the population. We also found that the height gap between Afro-Colombians and others decreased during the period under study by 0.7 cm for both men and women. While improvements were noticeable among the Afro-Colombians and those who chose not to be classified by ethnicity, in the case of the indigenous population only female cohorts registered an average-height increase of 1.5 cm. Moreover, we found that indigenous Colombians were more likely than other ethnic groups to experience an increase in biological well-being as a consequence of an improvement in their socio-economic status, thereby reducing the average-stature gap between them and the rest of the population by 2.1 and 3.6 cm for men and women, respectively.  相似文献   

20.
The integrated application of resistant crop varieties with biological control agents (BCAs) such as the Fusarium oxysporum [f.sp. strigae] strain “Foxy-2” has shown to be effective in fighting off the weed Striga hermonthica which is parasitic to several cereals cultivated in Sub-Saharan Africa (Schaub et al., 2006; Venne et al., 2009). “Foxy-2” proliferates in the rhizosphere and has been mainly studied for its virulence and mode of action. Contrary, no understanding is available regarding its interactions with key rhizosphere microorganisms steering relevant nutrient cycles in soils including nitrogen (N). In this study, we tested the hypothesis that “Foxy-2” displaces indigenous prokaryotic, N cycling communities in the maize rhizosphere due to competition for organic resources. Consequently, we evaluated if the application of an N-rich organic residue (i.e., Tithonia diversifolia with C/N ratio = 13, lignin content = 8.9%, polyphenol content = 1.7%) compensates these presumed competition effects. In a rhizobox experiment, quantitative polymerase chain reaction was used to follow the response of rhizosphere ammonia-oxidizing archaea (AOA) and bacteria (AOB) as well as total bacteria and archaea following “Foxy-2” inoculation in two physico-chemically contrasting soils (sandy Ferric Alisol versus clayey Humic Nitisol). Soils were treated with or without “Foxy-2”, S. hermonthica seeds, and T. diversifolia residues. Contrary to our expectations, we observed a distinct soil texture dependent, promoting effect of “Foxy-2” on rhizosphere prokaryotes. Abundance of AOA and total prokaryotic communities increased in response to “Foxy-2” in the sandy soil, while AOB remained unaffected. This effect on AOA was accelerated when T. diversifolia residues were incorporated. Further, in the clayey soil, AOA abundance was promoted when exposed to S. hermonthica infestation of maize. This suggested their capability to adapt to this biotic stress situation. It was concluded that “Foxy-2” did not pose a negative effect on targeted indigenous microorganisms, but the underlying mechanisms for the observed promoting effect of AOA abundance by “Foxy-2” inoculation are yet to be understood.  相似文献   

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