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991.
In this paper a complete design of a high speed optical motion analyzer system has been described. The main core of the image processing unit has been implemented by the differential algorithm procedure. Some intelligent and conservative procedures that facilitate the search algorithm have also been proposed and implemented for the processing of human motions. Moreover, an optimized modified direct linear transformation (MDLT) method has been used to reconstruct 3D markers positions which are used for deriving kinematic characteristics of the motion. Consequently, a set of complete tests using some simple mechanical devices were conducted to verify the system outputs. Considering the system verification for human motion analysis, we used the system for gait analysis and the results including joint angles showed good compatibility with other investigations. Furthermore, a sport application example of the system has been quantitatively presented and discussed for Iranian National Karate-kas. The low computational cost, the high precision in detecting and reconstructing marker position with 2.39 mm error, and the capability of capturing from any number of cameras to increase the domain of operation of the subject, has made the proposed method a reliable approach for real-time human motion analysis. No special environment limitation, portability, low cost hardware and built in units for simulations and kinematic analysis are the other significant specifications of this system.  相似文献   
992.
Twelve polymorphic microsatellite loci were isolated from polyploid alpine wood‐sorrel, Oxalis alpina (Oxalidaceae), and optimized for future studies of its breeding system. The loci were screened for variability among 72 individuals from Pinos Altos, New Mexico. The primers amplified loci with allele number ranging from two to 17 per locus and with estimates of Nei's genetic diversity varying from 0.10 to 0.99. These primers provide an opportunity to use polymorphic DNA markers to study the causes of breeding system variability in this species.  相似文献   
993.
Freshwater mussels (Unionidae) are among North America's most imperilled organisms. Mussels produce small larvae (glochidia) that parasitize aquatic vertebrates. We modified the Epicentre QuickExtract protocol to extract DNA from a single glochidium, collected directly from the marsupium of a female mussel, to use as template in polymerase chain reactions (PCRs). Yield per glochidium in a 40 µL extraction volume provided enough DNA for ≥ 15 PCRs per individual. We were successful in using this DNA for microsatellite analysis of up to three loci per individual. Offspring from one female showed evidence for multiple paternity within her brood. Our results are the first documentation of this phenomenon in freshwater mussels.  相似文献   
994.
Amorphous cellulose was used as a specific carrier for the deposition of self-assembled multienzyme complexes capable of catalyzing coupled reactions. Naturally glycosylated fungal cellobiohydrolases (CBHs) of glycosyl hydrolase families 6 and 7 were specifically deposited onto the cellulose surface through their family I cellulose-binding modules (CBM). Naturally glycosylated fungal laccase was then deposited onto the preformed glycoprotein layer pretreated by ConA, through the interaction of mannosyl moieties of fungal glycoproteins with the multivalent lectin. The formation of a cellulase-ConA-laccase composite was proven by direct and indirect determination of activity of immobilized laccase. In the absence of cellulases and ConA, no laccase deposition onto the cellulose surface was observed. Finally, basidiomycetous cellobiose dehydrogenase (CDH) was deposited onto the cellulose surface through the specific interaction of its FAD domain with cellulose. The obtained paste was applied onto the surface of a Clark-type oxygen electrode and covered with a dialysis membrane. In the presence of traces of catechol or dopamine as mediators, the obtained immobilized multienzyme composite was capable of the coupled oxidation of cellulose by dissolved oxygen, thus providing the basis for a sensitive assay of the mediator. Swollen amorphous cellulose plays three different roles in the obtained biosensor as: (i) a gelforming matrix that captures the analyte and its oxidized intermediate, (ii) a specific carrier for protein self-assembly, and (iii) a source of excess substrate for a pseudo-reagent-less assay with signal amplification. The detection limit of such a tri-enzyme biosensor is 50-100 nM dopamine.  相似文献   
995.
A multichannel automated chamber system was developed for continuous monitoring of CO2 exchange at multiple points between agro-ecosystem or soil and atmosphere. This system consisted of an automated chamber subsystem with a CO2 concentration analyzer and a data logging subsystem. Both subsystems were under the control of a programmable logic controller (PLC). The automated chamber subsystem contained 18 chambers (50 cm × 50 cm × 50 cm) and a compressor. The chamber lids were closed and can be automatically opened. During measurement, one of the 18 chambers was kept closed for three minutes for measuring and the other chambers were kept open to maintain the natural soil conditions to the maximum extent. Environmental variables were simultaneously measured using sensors and recorded by the data logger. The reliability of the multichannel automated chamber system was tested and the results showed that the turbulence of the fans had no significant effect on the CO2 exchange. The changes in the air and the temperature of soil and soil moisture inside the chambers, caused by the enclosure of the chambers, were not significant. The net ecosystem CO2 exchange for the wheat ecosystem was ?2.35 μmol·m?2·s>?1 and the soil respiration was 3.87 μmol·m?2·s>?1 in the wheat field, and 6.61 μmol·m?2·s>?1 in the apple orchard.  相似文献   
996.
Liu C  Du G S  Huang B B  Meng Q Y  Li H M  Wang Z J  Song F 《农业工程》2007,27(9):3670-3677
This research was carried on in constructed wetlands of Guan-Ting Reservoir, Beijing, China, from 2004 to 2005. The phytoplankon community was composed of 8 divisions (94 species, including genus and varieties) and the average cell density was 980.93× 104 cells per liter. The dominant divisions were Chlorophyta (36.8%), Bacillariophyta (31.0%) and Cyanophyta (23.4%). The removal rate of phytoplankton density was 72.7%. There was a positive linear correlation between phytoplankon density and total phosphorus. Here, 7 families (13 species) of aquatic vasular plants were found, which constituted emerging and submerging macrophyte communities. In the wetland system, the zooplankton community consisted of Protozoa, Rotifera, Cladocera and Copepoda (70 species). The average density was 4883 individuals per liter. Protozoan and Rotifera were the dominant groups and the removal rate of their density was 81.9%. The correlation between zooplankton and phytoplankton presented a quadratic curve. Also, the zoobenthos community contained Olisochaeta, Uniramia, Crustacea and Mollusca (15 species). The average density was 5670 individuals per m2 (62.3% was Uniramia) and the removal rate of their density was 92.4 %. The wetland system reduced CODMn, BOD5, TN, NH3-N, NO3-N, TP (total phosphor), PO4-P and SS in the water of Yong Ding River at 52.9%–99.1%.  相似文献   
997.
This study uses a geographical information system (GIS) and statistical analysis to look for patterns in referrals to a British cancer genetics service. In this case, familial cancers are taken to be those that can develop when an individual inherits DNA mutations that cause an increased risk of cancer. Between 1998 and 2006 the Cancer Genetics Service for Wales received nearly 11,000 referrals for patients resident in Wales and it is the service database recording those referrals which is the subject of this secondary analysis. Using postcodes to match referred patients to areas, deprivation scores were assigned. Referral rates per 10,000 head of population across the 8-year study period by unitary authority are presented, as is information on referrals from primary and secondary care sources by year. Each patient referred has their family history of cancer recorded and is assigned to a risk category; high, medium or average. There are correlations between number of GPs (General Practitioners) in a practice, number of patients referred from a practice, and deprivation as measured by the overall Welsh Index of Multiple Deprivation 2005, such that the two former factors increase as deprivation decreases. Over time there were changes in referral sources, with referrals from primary care overtaking those from secondary care in percentage and absolute terms. There were also changes in the types of cancer referred, risk categories seen and to which centre referrals were made. Referral patterns reveal an inverse relationship between deprivation and health service availability and use.  相似文献   
998.
Wang B S  Peng S L  Guo L  Ye Y H 《农业工程》2007,27(5):1690-1695
A novel landscape classification system was proposed in this study based on landscape ecological theory and the differentiation in climate, topography, soil, vegetation and land use mode. Five basic units (zone, tract, province, region and type) and two assistant units (sub and group) were used in this system. The tropical forest landscape in Hainan Island was regarded as a landscape province, belonging to global tropical forest landscape zone, Asiatic (oriental) tropical forest landscape tract and Chinese tropical forest landscape subtract. Based on the grade system of region, sub-region, type-group and type, this landscape province (Hainan Island) is divided into 6 landscape regions (east moist forest landscape, west semi-arid forest landscape, central-south mountainous forest landscape, tropical evergreen needle-leaved forest landscape, tropical bamboo landscape and tropical plantation landscape), 11 tropical forest landscape sub-regions represented by tropical lowland valley rain forest landscape, 26 tropical forest landscape-type groups represented by tropical lowland valley Dipterocarpaceae forest landscape, and 54 forest landscape types (FLT) represented by lowland valley Vatica mangachapoi forest. Generally, this classification system represents the landscape diversity of the tropical forest in Hainan Island. Further studies are needed to better understand the landscape diversity of Hainan Island.  相似文献   
999.
Objective: The aim of this study was to test the hypothesis that baroreflex sensitivity (BRS), assessed by indirect measurement of aortic pressure, is blunted in obesity. Additionally, the potential effect of cardiac autonomic nervous system (ANS) activity, aortic compliance, and metabolic parameters on BRS of obese subjects was investigated. Research Methods and Procedures: A group of 30 women with BMI >30 kg/m2 and a group of 30 controls with BMI <25 kg/m2 were examined. BRS was estimated by the sequence technique, cardiac ANS activity by short‐term spectral analysis of heart rate variability (HRV), and aortic compliance by the method of applanation tonometry. Results: BRS was lower in obese women (9.18 ± 3.77 vs. 19.63 ± 9.16 ms/mm Hg, p < 0.001). The median values (interquartile range) of the power of both the high‐frequency and low‐frequency components of the HRV were higher in the lean than in the obese participants [1079.2 (202.7 to 1716.9) vs. 224.1 (72.7 to 539.6) msec2, p = 0.001 and 411.8 (199.3 to 798.0) vs. 235.8 (99.4 to 424.5) msec2, p = 0.01 respectively]. Low‐to‐high‐frequency ratio values were higher in the obese subjects [0.82 (0.47 to 2.1) vs. 0.57 (0.28 to 0.89), p = 0.02]. Aortic augmentation values were not significantly different between lean and obese subjects. Multivariate analysis demonstrated a significant and independent association between BRS and age (p = 0.003), BMI (p < 0.001), and high‐frequency power of HRV (p < 0.001). These variables explained 72% of the variation of BRS values. Discussion: BRS is severely reduced in obese subjects. BMI, age, and the parasympathetic nervous system activity are the main determinants of BRS. Baroreflex behavior is of clinical relevance because an attenuated BRS represents a negative prognostic factor in cardiovascular diseases, which are common in obesity.  相似文献   
1000.
Early isolation experiments indicate that male songbirds learn their songs during an early sensitive period, although later work has shown that some open-ended learners modify songs in later years. Recent isolation experiments suggest that in some species song has a stronger genetic basis than previously thought. This study raised domestic canaries under different combinations of acoustic and social isolation and followed song development into the second year. Males raised alone in acoustic isolation developed songs with normal syllables, but larger repertoires and also produced syllables with lower repetition rates when compared to controls. The smallest repertoire occurred in males raised in a peer group. Isolate males had a smaller song control nucleus HVC than controls, but there was no effect on nucleus RA or on brain weight in general. In the second year, after introduction into a large normal colony, isolate and peer group males adjusted their syllable repertoire to normal size. In particular, the isolates reduced their repertoire even though the size of HVC showed a significant increase in volume. However, songs of isolate and peer group males still differ in repetition rate and number of single syllables in the common aviary. In contrast, control males showed low syllable turnover and no significant change in repertoire size. Nor did they show any significant change in the volumes of song control nuclei. It seems that complete isolation affects only some aspects of song and brain development, and later socialization corrects some but not all of these in the second year.  相似文献   
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