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1.
G. M. Foody 《Biometrical journal. Biometrische Zeitschrift》1996,38(2):181-193
In some classifications the importance of classes varies and it is desirable to weight allocation to selected classes. This is common in classifications of remotely sensed imagery, especially as class occurrence can vary markedly. If, for instance, there is prior knowledge on the distribution of class occurrence this weighting can be achieved with widely used statistical classifiers by setting appropriate a priori probabilities of class membership. With an arificial neural network the incorporation of prior knowledge is more problematic. An approach to weight class allocation in an artificial neural network classifcation by replicating selected training patterns is discussed. In comparison against a discriminant analysis for the classification of synthetic aperture radar imagery the results showed that training pattern replication could be used to weight class allocation with an effect similar to that of incorporating a priori probabilities of class membership into the discriminant analysis and resulted in a significant increase in classification accuracy. 相似文献
2.
Ryoko Sawamoto Takehiro Nozaki Tomoe Nishihara Tomokazu Furukawa Tomokazu Hata Gen Komaki Nobuyuki Sudo 《BioPsychoSocial medicine》2017,11(1):14
Background
Weight regain is a common problem following weight loss intervention, with most people who seek treatment for obesity able to lose weight, but few able to sustain the changes in behavior required to prevent subsequent weight regain. The identification of factors that predict which patients will successfully maintain weight loss or who are at risk of weight regain after weight loss intervention is necessary to improve the current weight maintenance strategies. The aim of the present study is identify factors associated with successful weight loss maintenance by women with overweight or obesity who completed group cognitive behavioral treatment (CBT) for weight loss.Methods
Ninety women with overweight or obesity completed a 7-month weight loss intervention. The data of 86 who completed follow-up surveys 12 and 24 months after the end of the treatment was analyzed. Depression, anxiety, binge eating, food addiction, and eating behaviors were assessed before and after the weight loss intervention. Participants who lost at least 10% of their initial weight during the weight loss intervention and had maintained the loss at the month 24 follow-up were defined as successful.Results
The intervention was successful for 27 participants (31.3%) and unsuccessful for 59 (68.6%). Multiple logistic regression analysis extracted larger weight reduction during the weight loss intervention, a lower disinhibition score, and a low food addiction score at the end of the weight loss intervention as associated with successful weight loss maintenance.Conclusion
The results suggest that larger weight reduction during the weight loss intervention and lower levels of disinhibition and food addiction at the end of the weight loss intervention predicted successful weight loss maintenance.Trial registration
Trial registry name: Development and validation of effective treatments of weight loss and weight-loss maintenance using cognitive behavioral therapy for obese patients.Registration ID: UMIN000006803Registered 1 January 2012.URL: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R0000080523.
4.
D A Leon 《BMJ (Clinical research ed.)》1991,303(6808):964-967
OBJECTIVE--To investigate the influence of birth weight on the pronounced social class differences in infant mortality in Britain. DESIGN--Analysis of routine data on births and infant deaths. SETTING--England and Wales. SUBJECTS--All live births and infant deaths, 1983-5. MAIN OUTCOME MEASURE--Mortality in infants by social class, birth weight, and legitimacy according to birth and death certificates. RESULTS--Neonatal and postneonatal mortality (deaths/1000 births) increased with social class. Neonatal and postneonatal mortality was 4.2/1000 and 2.3/1000 respectively for social class I and 6.8/1000 and 5.6/1000 respectively for social class V. Mortality was lower among births registered within marriage (postneonatal 3.5/1000; neonatal 5.2/1000) than among those jointly registered outside marriage (5.1/1000; 6.4/1000); mortality was highest in those solely registered outside marriage (7.2/1000; 7.0/1000). For neonatal mortality the effect of social class varied with birth weight. Social class had little effect on neonatal mortality in low birthweight babies and increasing effect in heavier babies. For postneonatal mortality the effect of social class was similar for all birth weights and was almost as steep as for all birth weights combined. CONCLUSION--Birth weight mediates little of the effect of social class on postneonatal mortality. 相似文献
5.
- At a so-called natural anaerobiosis during the first 48 hours of germination the concentration of ethanol in pea tissues increases (according to the cultivation conditions) up to 40 μmol per gram fresh weight.
- In a nitrogen atmosphere the content of ethanol in pea seedlings increases as well, and after a 90 hour incubation in N2 it can reach even 100 μmol ethanol per gram fresh weight. In older plants the content increases the most markedly in cotyledons, but considerable amounts were revealed also in stems and roots. Its increase in vegetative organs of plants cultivated both in light and darkness is more or less identical. Ethylalcohol can be formed by the vegetative organs themselves, as proved by the increase of this metabolite in plants deprived of reserve organs; in addition, however, it is evidently transported into them from reserve parts. Ethanol formed under anaerobiosis is catabolyzed after transferring plants to the air.
6.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1992,101(2):425-430
- 1.1. Two proteinases have been identified in yolk granules of Nereis diversicolor mature oocytes, an aminopeptidase and an acid cysteine proteinase.
- 2.2. The aminopeptidase was identified as a metallo-enzyme having a molecular weight of about 260 kDa.
- 3.3. Except that the acid cysteine proteinase is a high molecular weight protein (200 kDa) and has a very low pH optimum (3.0), the enzyme possesses properties resembling those of mammalian cathepsin L.
- 4.4. The cathepsin L-like proteinase was found to be liable to the in vitro proteolysis of the yolk granule proteins and is therefore suggested to be involved in yolk protein processing.
7.
8.
Gel Electrophoresis of Avian Leukosis and Sarcoma Viral RNA in Formamide: Comparison with Other Viral and Cellular RNA Species 总被引:65,自引:37,他引:28
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Class a and class b 30 to 40S RNA subunits obtained by heat dissociation from the 60 to 70S RNA complex of avian tumor viruses were compared with several RNA standards by electrophoresis in formamide-polyacrylamide gels. Class a RNA was found to have a lower electrophoretic mobility and hence probably a higher molecular weight than class b RNA. The absolute molecular weight of class a and b RNA could not be determined with accuracy, because the relationship between logarithm of molecular weight and mobility of the RNA standards was not linear. The size of class a RNA fell into the range of 2.4 x 10(6) to 3.4 x 10(6) daltons and that of class b into the range of 2.2 x 10(6) to 2.9 x 10(6) daltons, depending on the standards used. The possible biological significance of this difference is discussed. 相似文献
9.
《The International journal of biochemistry》1994,26(7):943-950
- 1.1. The role ofinterleukin-1 (IL-1) in sepsis-induced muscle proteolysis was assessed by treating septic rats with recombinant IL-1 receptor antagonist (rIL-Ira).
- 2.2. In initial experiments, we tested the effectiveness of IL-Ira in preventing muscle proteolysis induced by administration of IL-1.
- 3.3. When normal rats were treated with rIL-α (three intraperitoneal doses of 100 μ g/kg body weight each over 16 hr), total and myofibrillar muscle protein breakdown rates, measured as release oftyrosine and 3-methylhistidine, respectively, by incubated extensor digitorum longus muscles, were significantly increased.
- 4.4. This metabolic response to IL-α was completely abolished by rIL-Ira, administered as three intraperitoneal doses of 3 mg/kg body weight each over 16hr.
- 5.5. In subsequent experiments, sepsis was induced in rats by cecal ligation and puncture (CLP); non-septic rats were sham-operated.
- 6.6. Treatment of septic rats over 16hr with a total dose of 25mg/kg body weight of rIL-Ira reduced, but did not normalize, the increased muscle protein breakdown rates seen during sepsis.
- 7.7. When the dose of rIL-Ira was more than doubled and given as a constant infusion at a rate of 4.2 mg/kg body weight/hr for 16 hr, the increased rate of muscle proteolysis in septic rats was normalized.
- 8.8. The present study offers the first direct evidence that IL-1 is involved in the regulation of muscle proteolysis during sepsis.
10.
《Comparative biochemistry and physiology. A, Comparative physiology》1986,83(4):661-665
- 1.1. The weight and energy content of sloughed skins of 92 individual snakes of 22 different species in three families were measured.
- 2.2. Weight and total energy content of shed skins were highly correlated with body weight.
- 3.3. The heat of combustion (kJ/g) of sloughed skins varied significantly among families and was higher in species having unkeeled scales than in those with keeled scales.
- 4.4. The presence of keels significantly affected weight of skins, even when skin weight is adjusted for covariance with body weight.
- 5.5. Neither body weight nor ambient temperature significantly affected the heat of combustion of sloughed skins.
- 6.6. The energy content of shed skin, expressed as a proportion of daily metabolism, decreased with ambient temperature, but the effect is minimized in large snakes.
- 7.7. Small snakes expended relatively less energy in sloughed skins than large snakes when the expenditure is expressed in terms of total daily metabolized energy.
11.
《Comparative biochemistry and physiology. A, Comparative physiology》1981,68(2):285-288
- 1.1. A study was carried out on the correlation between total mass (living weight), wet and dry biomass, shell weight and opercular linear dimensions in a sample of Ampullaria canaliculata from southern Brazil.
- 2.2. A set of linear regression equations were derived, allowing estimation of mass eaten by predators, from shell weight or opercular dimensions. The equations also permit evaluation of standing biomass in the field.
- 3.3. It is possible to identify females in advanced stages of egg maturation using the live weight and the linear dimensions of the opercula.
12.
Lipid status and feeding habits of salmonid juveniles in the year preceding seaward migration as factors controlling their future smoltification 总被引:1,自引:1,他引:0
D. S. Pavlov N. N. Nemova P. I. Kirillov E. A. Kirillova Z. A. Nefedova O. B. Vasil’eva 《Journal of Ichthyology》2007,47(3):241-245
Juveniles of coho salmon Oncorhynchus kisutch (Walb.) and mykiss Parasalmo mykiss (Walbaum) of the same age (1+) become differentiated as early as eight months before smoltification and seaward migration by their lipid level, feeding habits, and size and weight parameters. It is found that juveniles of coho salmon and mykiss with a high lipid status have a greater (on average) length and weight and consume more calorific food items. The juveniles with a lower lipid status have a lower length and weight and consume less calorific organisms. It is presumed that a considerable part of juveniles with a high lipid status will migrate seaward next year. The role of the trophic factor in development of this differentiation and, accordingly, in determination of smoltification dates is discussed. 相似文献
13.
Namrata Dhaka Kadambini Rout Satish K. Yadava Yaspal Singh Sodhi Vibha Gupta Deepak Pental Akshay K. Pradhan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(2):293-307
Key message
Seed weight QTL identified in different populations were synthesized into consensus QTL which were shown to harbor candidate genes by in silico mapping. Allelic variation inferred would be useful in breeding B. juncea lines with high seed weight.Abstract
Seed weight is an important yield influencing trait in oilseed Brassicas and is a multigenic trait. Among the oilseed Brassicas, Brassica juncea harbors the maximum phenotypic variation wherein thousand seed weight varies from around 2.0 g to more than 7.0 g. In this study, we have undertaken quantitative trait locus/quantitative trait loci (QTL) analysis of seed weight in B. juncea using four bi-parental doubled-haploid populations. These four populations were derived from six lines (three Indian and three east European lines) with parental phenotypic values for thousand seed weight ranging from 2.0 to 7.6 g in different environments. Multi-environment QTL analysis of the four populations identified a total of 65 QTL ranging from 10 to 25 in each population. Meta-analysis of these component QTL of the four populations identified six ‘consensus’ QTL (C-QTL) in A3, A7, A10 and B3 by merging 33 of the 65 component Tsw QTL from different bi-parental populations. Allelic diversity analysis of these six C-QTL showed that Indian lines, Pusajaikisan and Varuna, hold the most positive allele in all the six C-QTL. In silico mapping of candidate genes with the consensus QTL localized 11 genes known to influence seed weight in Arabidopsis thaliana and also showed conserved crucifer blocks harboring seed weight QTL between the A subgenomes of B. juncea and B. rapa. These findings pave the way for a better understanding of the genetics of seed weight in the oilseed crop B. juncea and reveal the scope available for improvement of seed weight through marker-assisted breeding.14.
Wendy Yiting Chen Esteban Marcellin Jacky Hung Lars Keld Nielsen 《The Journal of biological chemistry》2009,284(27):18007-18014
The molecular weight of hyaluronan is important for its rheological and biological function. The molecular mechanisms underlying chain termination and hence molecular weight control remain poorly understood, not only for hyaluronan synthases but also for other β-polysaccharide synthases, e.g. cellulose, chitin, and 1,3-betaglucan synthases. In this work, we manipulated metabolite concentrations in the hyaluronan pathway by overexpressing the five genes of the hyaluronan synthesis operon in Streptococcus equi subsp. zooepidemicus. Overexpression of genes involved in UDP-glucuronic acid biosynthesis decreased molecular weight, whereas overexpression of genes involved in UDP-N-acetylglucosamine biosynthesis increased molecular weight. The highest molecular mass observed was at 3.4 ± 0.1 MDa twice that observed in the wild-type strain, 1.8 ± 0.1 MDa. The data indicate that (a) high molecular weight is achieved when an appropriate balance of UDP-N-acetylglucosamine and UDP-glucuronic acid is achieved, (b) UDP-N-acetylglucosamine exerts the dominant effect on molecular weight, and (c) the wild-type strain has suboptimal levels of UDP-N-acetylglucosamine. Consistent herewith molecular weight correlated strongly (ρ = 0.84, p = 3 × 10−5) with the concentration of UDP-N-acetylglucosamine. Data presented in this paper represent the first model for hyaluronan molecular weight control based on the concentration of activated sugar precursors. These results can be used to engineer strains producing high molecular weight hyaluronan and may provide insight into similar polymerization mechanisms in other polysaccharides.Hyaluronan (HA)3 is a linear polymer of a repeating disaccharide, β1–3 d-N-acetylglucosamine (GlcNAc) β1–4 d-glucuronic acid (GlcUA) (1) (see Fig. 1). Ubiquitous in the extracellular matrix in vertebrates, HA is particularly abundant in cartilage, synovial fluid, dermis, and the vitreous humor of the eye, where it serves specialized functions. HA also plays a critical role during fertilization and embryogenesis. In many group A and C streptococci, HA forms a capsule that helps these microbes evade the host immune system (2). HA molecular weight is important for the physiochemical as well as biological properties of HA. High molecular weight is important for HA to exert its unique rheological properties (3), for mucoadherence (4, 5), and anti-inflammatory effects (6, 7), whereas low molecular weight is a potent signaling molecule (8).Open in a separate windowFIGURE 1.Biosynthetic pathway of HA in S. zooepidemicus.HA is produced by a processive synthase (9, 10) from the activated sugar precursors, UDP-glucuronic acid (UDP-GlcUA) and UDP-N-acetylglucosamine (UDP-GlcNAc) (see Fig. 1). In addition to the HA synthase (hasA), streptococcal has operons encode for one or more enzymes involved in biosynthesis of the activated sugars (11). The Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) operon encodes for five genes: HA synthase (EC 2.4.1.212; hasA), UDP-glucose dehydrogenase (EC 1.1.1.22; hasB), UDP-glucose pyrophosphorylase (EC 2.7.7.9; hasC), a glmU paralog encoding for a dual function enzyme acetyltransferase and pyrophosphorylase activity (EC 2.3.1.4/EC 2.7.7.23; hasD), and a pgi paralog encoding for phosphoglucoisomerase (EC 5.3.1.9; hasE).Although the biosynthetic mechanism is well established, little is known about what controls HA molecular weight. This is true not only for HA, but also for the highly abundant β-polysaccharides: cellulose, chitin, and 1,3-betaglucan. Molecular weight is partly an intrinsic parameter of the HA synthase. Weigel and colleagues have demonstrated that, at least in vitro, mutation of conserved cysteine or polar residues in streptococcal HA synthases results in reduced molecular weight with limited effect on biosynthetic rate (12–14). In a vertebrate HA synthase from Xenopus, the mutation of a serine or a cysteine residue yielded HA of higher, lower, or similar molecular weight depending on the amino acid substitution (15).We and others have demonstrated that in vivo molecular weight is also affected by culture parameters, e.g. temperature and aeration (16–20). Although changed culture conditions affect the physiochemical environment of the HA synthase, a more likely explanation is that molecular weight is affected by the availability of activated sugar substrates (UDP-GlcUA and UDP-GlcNAc) as well as the concentration of possible effector molecules, such as free UDP (21). Although such a mechanism has been suggested for several processive synthases (22, 23), there has never been any direct evidence linking molecular weight to the concentration of a substrate.Experimental support for the hypothesis has been obtained for the type 3 polysaccharide of Streptococcus pneumoniae (24). Like HA, the type 3 polysaccharide in S. pneumoniae is synthesized by a processive synthase from alternating addition of activated sugars, in this case UDP-glucose (UDP-Glc) and UDP-GlcUA. Mutants with reduced UDP-glucose dehydrogenase (“hasB”) activity not only produce less polysaccharide, but also polysaccharide with lower molecular weight (24). Although the levels of UDP-GlcUA were below detection in all strains, this supports the idea that UDP-GlcUA concentration controls molecular weight. Moreover, it is consistent with previous in vitro studies showing that low levels of UDP-GlcUA cause chain termination and hence low molecular weight (25). It was proposed that the concentration of UDP-GlcUA is critical for the successful transition from oligosaccharide lipid to highly processive polysaccharide synthesis (26). A similar mechanism is not likely for HA biosynthesis, because there is no indication that the HA synthase needs a primer (27).In the present study, we manipulated metabolite concentrations in the HA pathway by overexpressing the five genes in the has operon of S. zooepidemicus (Fig. 1). Overexpression of these genes had a profound effect on HA molecular weight, which correlated with the levels of UDP-sugars and in particular, UDP-GlcNAc. 相似文献
15.
印度地鼠的性成熟和窝仔数 总被引:1,自引:0,他引:1
Rubina ARSHAD 《动物学报》2004,50(5):723-729
为有效地进行有害脊椎动物的控制 ,研究了栖息于巴基斯坦Punjab中部的 348只印度地鼠的繁殖模式。在所捕捉到的 10 7雄鼠和 2 4 1只雌鼠中 ,分别有 75只和 179只是性成熟的个体。性比偏雌。使用被捕个体标本的体重和体长作为指标 ,发现最小的性成熟的雄性个体体重为 70 - 89g ,体长 13 1- 14 0cm ;一窝仔里面的平均胚胎数为 2 74± 0 15 (范围 ,1- 5 ) ,而平均胎斑数为 4 2 9± 0 19(1- 11) .体重似乎对窝仔数有显著影响 ,而体长和估计的年龄对窝仔数没影响。当老鼠繁殖不活跃和不繁殖时 ,控制害兽最有效 相似文献
16.
《The Journal of cell biology》1982,95(2):478-486
The properties of brain fodrin have been analyzed and compared with those of erythrocyte spectrin. Both proteins consist of high molecular weight polypeptide doublets on SDS polyacrylamide gels and in solution behave as very large asymmetric molecules. Both proteins show a characteristic increase in sedimentation coefficient in the presence of 20 mM KCl. Antibodies against the brain protein cross-react with erythrocyte spectrin and cross-react with similar high molecular weight doublet polypeptides in SDS polyacrylamide gels of other cell types and plasma membrane preparations. Both proteins bind actin. The brain protein and erythrocyte spectrin show specific and competitive binding to erythrocyte membranes and this binding is inhibited by antibodies against erythrocyte ankyrin. Several of these properties distinguish these proteins from the class of high molecular weight actin-binding proteins that includes filamin and macrophage actin-binding protein. We conclude that together with erythrocyte spectrin, the brain protein and equivalent, immunologically related proteins in other cell types belong to a single class of proteins with the common function of attachment of actin to plasma membranes. Based on the structural and functional similarities, the name spectrin would seem appropriate for this whole class of proteins. 相似文献
17.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1993,104(3):717-718
- 1.1. We dissected, homogenized and prepared ganglia and connectives from the central nervous system of medicinal leeches for SDS gel electrophoresis. The isolated proteins were transferred to nitrocellulose and incubated with affinity column-purified antibodies.
- 2.2. The immunoblots showed a strong positive reaction of a bovine carbonic anhydrase standard at a molecular weight of 29 kDa, and a distinct double-bond at the same molecular weight in the analyzed material.
- 3.3. We demonstrated with rat antibodies that carbonic anhydrase II is detectable in the leech central nervous system as the main isoenzyme.
- 4.4. The biochemical knowledge of carbonic anhydrase reported here agrees well with the immunocytochemical locations, thus affirming the validity of specific staining.
18.
We investigate the association between obesity and use of prescribed medications in England. Data were taken from fourteen rounds of the Health Survey for England (1999–2012), which has measures of current prescribed medication use based on therapeutic classifications in the British National Formulary, and nurse-measured height and weight. We find that obesity has a statistically significant and positive association with use of a range of medicines for managing diseases associated with obesity. The mean probability of using any type of medication is 0.40 in those of normal weight, 0.44 in the overweight, 0.52 in obesity class I and 0.60 in obesity class II/III. Significant positive associations were found between obesity and the use of medication for diseases of the cardiovascular system, gastrointestinal system, respiratory system, and central nervous system, as well as for infections, endocrine system disorders, gynaecological/urinary disorders and musculoskeletal and joint disorders. Use of anti-obesity medication is low, even among those with class II/III obesity. 相似文献
19.
Background
The objective of this study was to assess whether sex-specific differences in fetal and infant growth exist.Methods
This study was embedded in the Generation R Study, a population-based prospective birth cohort. In total, 8556 live singleton births were included. Fetal growth was assessed by ultrasound. During the first trimester, crown-rump-length (CRL) was measured. In the second and third trimester of pregnancy head circumference (HC), abdominal circumference (AC) and femur length (FL) were assessed. Information on infant growth during the first 2 years of life was obtained from Community Health Centers and included HC, body weight and length.Results
In the first trimester, male CRL was larger than female CRL (0.12 SD [95% CI 0.03,0.22]). From the second trimester onwards, HC and AC were larger in males than in females (0.30 SD [95% CI 0.26,0.34] and 0.09 SD [95% CI 0.05,0.014], respectively). However, FL in males was smaller compared to female fetuses (0.21 SD [95% CI 0.17,0.26]). Repeated measurement analyses showed a different prenatal as well as postnatal HC growth pattern between males and females. A different pattern in body weight was observed with a higher body weight in males until the age of 12 months where after females have a higher body weight.Conclusions
Sex affects both fetal as well as infant growth. Besides body size, also body proportions differ between males and females with different growth patterns. This sexual dimorphism might arise from differences in fetal programming with sex specific health differences as a consequence in later life.20.
J F Houssais 《FEBS letters》1975,56(2):341-347
Separation of nuclear Hn-RNP particles into two density classes, following isopy cnic centrifugation in metrizamide gradients, is reported. One class (density 1.31 g/ml) is rapidly labelled, and contains polydisperse heterogeneous high molecular weight particles, easily diffusible from intact nuclei under certain conditions. The other class (density 1.18 g/ml) is of lower molecular weight, not diffusible, and needs apparently a longer time to be labelled and/or to accumulate inside the nuclei. 相似文献