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101.
102.
Aim To study the present‐day olive stands and their ecology in the eastern part of the territory of the ancient city of Sagalassos, to study the variation of olive pollen production and dispersal near the olive stands, to establish a modern pollen reference model, and to compare Hellenistic–Roman pollen data from two wetlands with this modern reference model. Location Eastern part of the territory of the ancient city of Sagalassos, western Taurus mountain range in south‐west Turkey. Methods The study is based on field survey, pollen analysis of surface samples, multivariate statistics of modern pollen data and the use of ‘modern analogues’ in comparison with Hellenistic–Roman pollen samples. Results A field survey revealed the presence of 35 olive stands in the study area. These are mainly small‐scale stands. The olive pollen representation in the surface samples is highly variable. Two groups of modern ‘olive’ pollen spectra could be distinguished: (1) a group representing mainly olive stands from lush and moist mixed orchards; and (2) a group representing mainly olive stands from open small‐scale olive stands in combination with annual crop agriculture. Although no ‘perfect’ modern analogue was found for the Hellenistic–Roman pollen data, the fossil pollen data show similarities with modern spectra from the second group, due to the presence of relatively high pollen values for secondary anthropogenic indicators. Main conclusion A well‐organized and diverse, but time‐ and energy‐consuming, agricultural system was maintained nearby the wetlands of Çanakl? soils, presumably to maximize the yields in both valleys.  相似文献   
103.
Using the strictly neutral model as a null hypothesis, we tested for deviations from expected levels of nucleotide polymorphism at the alcohol dehydrogenase locus (Adh-1) within and among four species of pocket gophers (Geomys bursarius major, G. knoxjonesi, G. texensis llanensis, and G. attwateri). The complete protein-encoding region was examined, and 10 unique alleles, representing both electromorphic and cryptic alleles, were used to test hypotheses (e.g., the neutral model) concerning the maintenance of genetic variation. Nineteen variable sites were identified among the 10 alleles examined, including 9 segregating sites occurring in synonymous positions and 10 that were nonsynonymous. Several statistical methods, including those that test for within-species variation as well as those that examine variation within and among species, failed to reject the null hypothesis that variation (both within and between species of Geomys) at the Adh locus is consistent with the neutral theory. However, there was significant heterogeneity in the ratio of polymorphism to divergence across the gene, with polymorphisms clustered in the first half of the coding region and fixed differences clustered in the second half of the gene. Two alternative hypotheses are discussed as possible explanations for this heterogeneity: an old balanced polymorphism in the first half of the gene or a recent selective sweep in the second half of the gene.   相似文献   
104.
The floral development and anatomy ofChrysosplenium alternifolium were studied with the scanning electron microscope and light microscope to understand the initiation sequence of the floral organs and the morphology of the flower, and to find suitable floral characters to interpret the systematic position of the genus within the Saxifragaceae. The tetramerous flower shows a highly variable initiation sequence. The median sepals and first stamens arise in a paired sequence resembling a dimerous arrangement, but the first sepal and stamen arise on the side opposite to the bract. Transversal sepals and stamens emerge sequentially, as one side often precedes the other; sepals and stamens occasionally arise on common primordia. Initiation of the gynoecium is more constant with two median carpel primordia arising on a sunken floral apex. Several flowers were found to be pentamerous with a 2/5 initiation sequence. Flowers were invariably found to be apetalous without traces of petals in primordial stages; this condition is interpreted as an apomorphy. It is postulated that the development of a broad gynoecial nectary is responsible for the occurrence of an obdiplostemonous androecium. The gynoecium shows a number of anatomical particularities not observed in other Saxifragaceae. The presence and distribution of colleters is discussed.  相似文献   
105.
Abstract Batch mating experiments were employed to study the kinetics of the conjugal transfer of a TOL plasmid, using the transconjugant strain Pseudomonas aeruginosa PAO 1162 (TOL) as the plasmid donor and Pseudomonas putida PB 2442 and Pseudomonas aeruginosa PAO 1162N as the plasmid recipients. Transfer rates from PAO 1162 (TOL) to PAO 1162N and PB 2442 measured for exponentially grown PAO 1162 (TOL) were 1.81 × 10−14 (standard error (S.E.) 1.25 × 10−15) ml·cell−1min−1 and 3.32 × 10−13 (S.E. 4.42 × 10−14) ml·cell−1min−1, respectively. The instability of the TOL plasmid in PAO 1162 (TOL) was evaluated under conditions that were non-selective for maintenance of the TOL catabolic functions. The measured rates of instability were 6.7 10−6 to 8.3 10−6 min−1, and the loss of the catabolic functions was mainly caused by structural instability of the plasmid.  相似文献   
106.
Experiments were performed to localize the hepatic microsomal enzymes of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol biosynthesis to the cytoplasmic or lumenal surface of microsomal vesicles. Greater than 90 percent of the activities of fatty acid-CoA ligase (EC 6.2.1.3), sn-glycerol 3-phosphate acyltransferase (EC 2.3.1.15), lysophosphatidic acid acyltransferase, diacylglycerol acyltransferase (EC 2.3.1.20), diacylglycerol cholinephosphotransferase (EC 2.7.8.2), and diacylglycerol ethanolaminephosphotransferase (EC 2.7.8.1) was inactivated by proteolysis of intact microsomal vesicles. The phosphatidic acid phosphatase (EC 3.1.3.4) was not inactivated by any of the protease tested. Under conditions employed, <5 percent of the luminal mannose-6-phosphatase (EC 3.1.3.9) activity was lost. After microsomal integrity was disrupted with detergents, protease treatment resulted in a loss of >74 percent of the mannose-6-phosphatase activity. The latency of the mannose-6-phosphatase activity was not affected by protease treatment. Mannose-6-phosphatase latency was not decreased by the presence of the assay components of several of the lipid biosynthetic activities, indicating that those components did not disrupt the microsomal vesicles. None of the lipid biosynthetic activities appeared latent. The presence of a protease-sensitive component of these biosynthetic activities on the cytoplasmic surface of microsomal vesicles, and the absence of latency for any of these biosynthetic activities suggest that the biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol occurs asymmetrically on the cytoplasmic surface of the endoplasmic reticulum. The location of biosynthetic activities within the transverse plane of the endoplasmic reticulum is of particular interest for enzymes whose products may be either secreted or retained within the cell. Phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol account for the vast majority of hepatic glycerolipid biosynthesis. The phospholipids are utilized for hepatic membrane biogenesis and for the formation of lipoproteins, and the triacylglycerols are incorporated into lipoproteins or accumulate within the hepatocyte in certain disease states (14). The enzymes responsible for the biosynthesis of these glycerolipids (Scheme I) from fatty acids and glycerol-3P have all been localized to the microsomal subcellular fraction (12, 16, 29, 30). Microsomes are derived from the endoplasmic reticulum and are sealed vesicles which maintain proper sidedness. (11, 22). The external surface of these vesicles corresponds to the cytoplasmic surface of the endoplasmic reticulum. Macromolecules destined for secretion must pass into the lumen of the endoplasmic reticulum (5, 23). Uncharged molecules of up to approximately 600 daltons are able to enter the lumen of rat liver microsomes, but macromolecules and charged molecules of low molecular weight do not cross the vesicle membrane (10, 11). Because proteases neither cross the microsomal membrane nor destroy the permeability barrier of the microsomal vesicles, only the enzymes and proteins located on the cytoplasmic surface of microsomal vesicles are susceptible to proteolysis unless membrane integrity is disrupted (10, 11). By use of this approach, several enzymes and proteins have been localized in the transverse plane of microsomal membranes (11). With the possible exception of cytochrome P 450, all of the enzymes and proteins investigated were localized asymmetrically by the proteolysis technique (11). By studies of this type, as well as by product localization, glucose-6-phosphate (EC 3.1.3.9) has been localized to the luminal surface of microsomal vesicles (11) and of the endoplasmic reticulum (18, 19). All microsomal vesicles contain glucose-6-phosphatase (18, 19) which can effectively utilize mannose-6-P as a substrate, provided the permeability barrier of the vesicles has been disrupted to allow the substrate access to the active site located on the lumenal surface (4). An exact correspondence between mannose- 6-phosphate activity and membrane permeability to EDTA has been established (4). The latency of mannose-6-phosphatase activity provides a quantitative index of microsomal integrity (4.) Few of the microsomal enzymes in the synthesis of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol have been solubilized and/or purified, and little is known about the topography of these enzymes in the transverse or lateral planes of the endoplasmic reticulum. An asymmetric location of these biosynthetic enzymes on the cytoplasmic or lumenal surface of microsomal vesicles may provide a mechanism for regulation of the glycerolipids to be retained or secreted by the cell, and for the biogenesis of asymmetric phospholipid bilayers. In this paper, we report investigations on the localization of all seven microsomal enzymes (Scheme I) in the biosynthesis of triacylglycerol, phosphatidylcholine, and phosphatidylethanolamine, using the protease technique with mannose-6-phosphatase serving as luminal control activity. The latency of these lipid biosynthetic enzymes was also investigated, using the latency of mannose-6-phosphatase as an index of microsomal integrity.  相似文献   
107.
RU 41740 (Biostim) is an immunomodulator clinically used for the treatment of chronic bronchitis and recurrent pulmonary infections. In these diseases large amounts of mucus are produced which congest the bronchi. A major glycosaminoglycan constituent of this mucus is hyaluronic acid, one of the largest molecules in nature; its metabolic degradation is carried out by 3 acid hydrolases: hyaluronidase, beta-N-acetylglucosaminidase, and beta-glucuronidase. In the lung these enzymes are especially synthesized and active in alveolar macrophages. It was thus interesting to study the effect of RU 41740 administration on the hyaluronic acid-degrading activity of these cells. This compound was given by gastric gavage to rats and the activities of lung alveolar macrophage and alveolar fluid hyaluronidase, beta-N-acetylglucosaminidase, beta-glucuronidase, and acid phosphatase as a lysosomal marker were determined. The effect on macrophage proliferation was also examined. The results obtained showed that: (1) unstimulated alveolar macrophages display the remarkable property, compared with other cell types, that hyaluronidase activity is about equally distributed between the inside and the outside of the cell; (2) RU 41740 administration increases the total activity of the 4 enzymes studied in the alveolar macrophages without inducing any increase in the number of macrophages; (3) the intracellular activities of beta-N-acetylglucosaminidase and beta-glucuronidase are markedly increased, whereas intracellular hyaluronidase activity is not changed. However, in the extracellular fluid only hyaluronidase activity is highly increased; (4) even the lysosomal marker enzyme acid phosphatase has only its intracellular activity increased. This would suggest the possibility that other lysosomal enzymes may also be increased by this immunomodulator.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
108.
109.
BackgroundFamilies in high mortality settings need regular contact with high quality services, but existing population-based measurements of contacts do not reflect quality. To address this, in 2012, we designed linked household and frontline worker surveys for Gombe State, Nigeria, Ethiopia, and Uttar Pradesh, India. Using reported frequency and content of contacts, we present a method for estimating the population level coverage of high quality contacts.ConclusionsMeasuring content of care to reflect the quality of contacts can reveal missed opportunities to deliver best possible health care.  相似文献   
110.
The performance of the activated sludge process is limited by the ability of the sedimentation tank (1) to separate the activated sludge from the treated effluent and (2) to concentrate it. Apart from bad operating strategies or poorly designed clarifiers, settling failures can mainly be attributed to filamentous bulking. Image analysis is a promising technique that can be used for early detection of filamentous bulking. The aim of this paper is therefore twofold. Foremost, correlations are sought between image analysis information (i.e., the total filament length per image, the mean form factor, the mean equivalent floc diameter, the mean floc roundness and the mean floc reduced radius of gyration) and classical measurements (i.e., the Sludge Volume Index (SVI)). Secondly, this information is both explored and exploited in order to identify dynamic ARX and state space-type models. Their performance is compared based on two criteria.  相似文献   
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