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1.
Siliang Gao Yujun Wang Wenwen Wang Guangsheng Luo Youyuan Dai 《Journal of Molecular Catalysis .B, Enzymatic》2010,62(3-4):218-224
Hydrophobic silica aerogels modified with methyl group were applied as support to immobilize Candida rugosa lipase (CRL). At the adsorption process, different alcohols were used to intensify the immobilization of CRL. The results showed that n-butanol wetting the hydrophobic support prior to contacting with enzyme solution could promote lipase activity, but the adsorption quantity onto the support decreased. Based on this, a novel immobilization method was proposed: the support contacted with enzyme solution without any alcohols, and then the immobilized enzymes were activated by 90% (V) n-butanol solution. The experimental results showed that this method could keep high adsorption quantity (413.0 mg protein/g support) and increase the lipase specific activity by more than 50%. To improve the stability of immobilized lipase, the support after adsorption was contacted with n-octane to form an oil layer covering the immobilized lipases, thus the leakage can be decreased from over 30–4% within 24 h. By utilizing proper cosolvents, a high enzyme activity and loading capacity as well as little loss of lipase was achieved without covalent linkage between the lipase and the support. This is known to be an excellent result for immobilization achieved by physical adsorption only. 相似文献
2.
Background
Social support is frequently linked to positive parenting behavior. Similarly, studies increasingly show a link between neighborhood residential environment and positive parenting behavior. However, less is known about how the residential environment influences parental social support. To address this gap, we examine the relationship between neighborhood concentrated disadvantage and collective efficacy and the level and change in parental caregiver perceptions of non-familial social support.Methodology/Principal Findings
The data for this study came from three data sources, the Project on Human Development in Chicago Neighborhoods (PHDCN) Study''s Longitudinal Cohort Survey of caregivers and their offspring, a Community Survey of adult residents in these same neighborhoods and the 1990 Census. Social support is measured at Wave 1 and Wave 3 and neighborhood characteristics are measured at Wave 1. Multilevel linear regression models are fit. The results show that neighborhood collective efficacy is a significant (ß = .04; SE = .02; p = .03), predictor of the positive change in perceived social support over a 7 year period, however, not of the level of social support, adjusting for key compositional variables and neighborhood concentrated disadvantage. In contrast concentrated neighborhood disadvantage is not a significant predictor of either the level or change in social support.Conclusion
Our finding suggests that neighborhood collective efficacy may be important for inducing the perception of support from friends in parental caregivers over time. 相似文献3.
Health related quality of life in adult cancer survivors: Importance of social and emotional support
BackgroundAdult cancer survivors (ACS) are at increased risk for developing various comorbid conditions and having poor health-related quality of life (HRQOL) when compared to adults with no history of cancer. The effect of social and emotional support on HRQOL among ACS is not fully elucidated. The purpose of this study was to understand the role of social and emotional support on HRQOL in ACS and to examine if the association between social and emotional support and HRQOL is modified by gender, time since cancer diagnosis, or marital status.MethodsData for this study were obtained from the 2009 Behavioral Risk Factor Surveillance System. Statistical analysis was based on ACS with complete data (n = 23,939) on all variables considered. Multivariable logistic regression models were used to model the association between social and emotional support and indicators of HRQOL (i.e., general health, physical health, mental health, and activity limitation). To examine if gender, marital status, or the number of years since cancer diagnosis modify the association, separate stratified analyses were conducted.ResultsWhen compared to ACS who reported that they Rarely/Never received social and emotional support, those who reported that they Always received were 32 % less likely to report Fair/Poor General health, 23 % less likely to report frequent unhealthy days of Physical health, 73 % less likely to report frequent unhealthy days of Mental health and 38 % less likely to report frequent unhealthy days of Activity limitation. Social and emotional support was positively associated with all four domains of HRQOL among ACS who were female, unmarried, or greater than 5 years since cancer diagnosis, while this positive association was evident only with one or two domains of HRQOL among their corresponding counterparts (i.e., male, married, less than 5 years since diagnosis).ConclusionsSocial and emotional support is an important factor directly related to a better HRQOL, but it is modified by gender, marital status, and time since diagnosis. Findings from this study should inform health care providers about the importance of a support system for ACS in improving their overall quality of life. 相似文献
4.
葎草[Humulus scandens(Lour.)Merr.]为草本雌雄异株攀援植物,采用野生种群人为控制的方法,设置分枝找到乔木支持物(高度(3±0.5)m)、灌木支持物(高度(1±0.5)m)和无支持物3种生长方式,测定雌(♀)、雄(♂)株分枝的叶面积参数、光合参数、叶绿素含量、可溶性糖含量及茎、叶、花在分枝、构件、单株水平下生物量分配比等指标,分析支持物对分枝光合特性和生物量结构的影响,探讨雌、雄分枝利用支持物的性别差异及响应支持物的生态适应差异。结果表明:(1)分枝的单叶面积、总叶面积、叶面积比率、比叶面积对支持物响应存在性别差异,♀株叶面积参数均大于♂株;支持物差异主要影响叶绿素a含量,对叶绿素b、叶绿素a/b影响不显著。(2)支持物差异对分枝叶片的光合参数均有显著的影响(P0.05),支持物对光合参数影响顺序为GsPnTrCi,性别差异影响顺序为GsTrPnCi;可溶性糖含量在性别间、支持物间均表现出极显著的差异(P0.01),♂株糖含量显著高于♀株。(3)在分枝水平下,♀株叶、茎及花生物量分配比都未受到支持物不同的影响(P≥0.05),而♂株在叶、茎的生物量分配比方面受影响显著(P0.05);在构件水平下,支持物差异显著影响了♂株分枝间的营养生长构件分配比,显著影响了♀株分枝间的生殖生长构件分配比;在单株水平下,叶分配比仅在支持物间差异显著(P0.05),而茎、花分配比在性别间、支持物间均有显著差异。(4)雌雄分枝的光合特性和生物量结构对不同支持物的响应差异明显,使葎草单株的生理整合性和适应性大幅度提高。研究以雌雄异株攀援植物为材料,从分枝水平分析支持物对雌雄株光合特性及生物量结构的影响,研究结果对探讨雌雄异株攀援植物的生态适应性具一定的价值。 相似文献
5.
Julien Benoit Nick Crumpton Samuel Merigeaud Rodolphe Tabuce 《Journal of Mammalian Evolution》2014,21(2):173-193
Interest in the phylogeny of Macroscelididae (sengis or elephant shrews) has been prompted by molecular studies indicating that Elephantulus rozeti is best placed as the sister group of Petrodromus tetradactylus (this clade being in turn the sister taxon to Macroscelides proboscideus) than among other species of the genus Elephantulus. Until now, no discrete morphological characters have been proposed to support the grouping of E. rozeti, Petrodromus, and Macroscelides into this single so-called ‘Panelephantulus’ clade. Here, we employed μCT scanning in order to investigate the petrosal and bony labyrinth (bony capsule of the inner ear) morphology of most species of extant Macroscelididae. We performed a cladistic analysis on ear traits and found that despite some convergences (e.g., concerning the bony arterial canals in Macroscelides and Rhynchocyon) the middle and inner ear morphology furnishes significant support for the ‘Panelephantulus’ clade. In our analysis, this clade is unambigously supported by the presence of a fully ossified stapediofacial tube. Two additional characters (the presence of a bony septum at the mouth of the fenestra cochleae dividing the D3 sinus into two distinct cavities and the absence of an accessory lateral pneumatic fossa) could also support ‘Panelephantulus.’ These newly discovered morphological characters support the molecular phylogenies published and highlight the importance of coding hitherto difficult to sample morphologies within cladistic analyses using micro-CT techniques. Taxonomic implications are briefly discussed. 相似文献
6.
《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1998,321(7):603-609
Phylogenetic relationships among fungi belonging to the family of Ustilaginaceae (genera Microbotryum, Sphacelotheca, Ustilago, Sporisorium) are inferred from a parsimony analysis using the ITS sequences of nuclear ribosomal genes. The introduction in the phylogeny of sequences from species of Suillus, Puccinia and Taphrina as outgroup shows the polyphyletism of this family. These results support the division of this taxon into two groups: Ustilaginaceae s. str. formed only by the pathogens of Poaceae, and Microbotryaceae constituted by the pathogens of Dicotyledons. Furthermore, we proposed to extend the host plant spectrum of Ustilaginaceae s. str. to all the Monocotyledons. Several discriminating characteristics are listed to support this distinction. 相似文献
7.
Dionisios Youlatos 《Mammalian Biology》2010,75(6):475-481
The present report aims to quantify the use of zygodactylous (opposability of digits II to III) grasping in relation to positional modes and support size and orientation, in the highly arboreal, walking/climbing woolly opossum, Caluromys philander. For this purpose, four captive adult C. philander were intensively video-recorded and their positional behavior, hand grasp, and support size and orientation use were analyzed frame-by-frame. Overall, C. philander used a zygodactylous grasp in 81.3±1.2% of bouts. In terms of support features, this grasp was particularly common on (a) supports that could be wholly and partly held by the animals’ hand and (b) vertical supports in particular. In a comparable manner, zygodactyly dominated during above-support positional modes, but was significantly less used during bridging and suspension. The results show that zygodactyly provided an above-support secure and steady grasp on relatively unstable arboreal supports, by aligning the hand with the main axis of the support. This very likely assisted in controlling over the applied torques during cautious quadrupedal and climbing activities with extended hand contact that characterizes the locomotor strategy of C. philander. These observations need to be further tested by more detailed kinetic studies and on a larger sample of arboreal didelphids. 相似文献
8.
Climbing capacity of invasive climbers is an important parameter to evaluate in the species invasive potential and processes in forests. However, this feature has not attracted the attention of invasion biologists. In the present study, we assessed the climbing traits and capacity of Mikania micrantha; a herbaceous invasive stem-twiner by supplying artificial vertical supports of different sizes ranging from 1.0 to 8.0 cm in diameter. We also calculated the theoretical maximum usable host size of a M. micrantha shoot based on confirm of the hypothesis that curvature of M. micrantha shoots will remain constant and not affected by support pole size. A total 164-tested M. micrantha shoots ascended the supports successfully. Shoot success rate declined significantly when support diameter exceeded 5.0 cm. The largest pole M. micrantha ascended successfully was 6.6 cm, while the theoretical value is 7.5 cm on average. Curvature declined significantly with increasing shoot diameter. However, no significant correlation was detected between curvature and support diameter, and most M. micrantha shoots maintained relatively constant curvature within a small fluctuation range (0.1–0.2 cm?1) near the average value (0.16 cm?1). We compared our results with the only two similar studies available, and concluded that climbing shoot ascent angle on supports decreased with increasing support diameter, while curvature remained constant, which was not affected by support size. These appear to be common attributes for herbaceous stem-twiners. Maximum usable host size was an important factor for successful M. micrantha ascent. We recommend this as a vital criterion in species management. 相似文献
9.
Liliana Snchez-Gonzlez Laura E. Adams Rafael Saavedra Emma M. Little Nicole A. Medina Chelsea G. Major Marina Bruck Julieanne Miranda Coral Rosado-Santiago Kyle Ryff Marianyoly Ortiz Grayson Brown Roberto Barrera Carmen L. Prez-Guerra Vanessa Rivera-Amill Gabriela Paz-Bailey 《PLoS neglected tropical diseases》2021,15(12)
Arboviral diseases transmitted by Aedes species mosquitoes pose an increasing public health challenge in tropical regions. Wolbachia-mediated population suppression (Wolbachia suppression) is a vector control method used to reduce Aedes mosquito populations by introducing male mosquitoes infected with Wolbachia, a naturally occurring endosymbiotic bacterium. When Wolbachia-infected male mosquitoes mate with female wild mosquitoes, the resulting eggs will not hatch. Public support is vital to the successful implementation and sustainability of vector control interventions. Communities Organized to Prevent Arboviruses (COPA) is a cohort study to determine the incidence of arboviral disease in Ponce, Puerto Rico and evaluate vector control methods. Focus groups were conducted with residents of COPA communities to gather their opinion on vector control methods; during 2018–2019, adult COPA participants were interviewed regarding their views on Wolbachia suppression; and a follow-up questionnaire was conducted among a subset of participants and non-participants residing in COPA communities. We analyzed factors associated with support for this method. Among 1,528 participants in the baseline survey, median age was 37 years and 63% were female. A total of 1,032 (68%) respondents supported Wolbachia suppression. Respondents with an income of $40,000 or more were 1.34 times as likely [95% CI: 1.03, 1.37] to support Wolbachia suppression than those who earned less than $40,000 annually. Respondents who reported repellant use were 1.19 times as likely to support Wolbachia suppression [95% CI: 1.03, 1.37]. A follow-up survey in 2020 showed that most COPA participants (86%) and non-participants living in COPA communities (84%) supported Wolbachia suppression during and after an educational campaign. The most frequent questions regarding this method were related to its impact on human and animal health, and the environment. Continuous community engagement and education efforts before and during the implementation of novel vector control interventions are necessary to increase and maintain community support. 相似文献
10.
Debate over wealth redistribution plays a prominent role in society, but the causes of differences in support for redistribution remain contested. A recent three-person two-situation model suggests these differences are shaped by evolved motivational systems of self-interest, compassion, and dispositional envy. We conducted a close replication testing this prediction, all subjects were British, recruited from an online subject pool. Study 1 (N = 206) confirmed the roles of self-interest (β = 0.20) and compassion for others (β = 0.37), as well as a predicted null effect of procedural fairness. Dispositional envy was non-significant (β = 0.06). In study 2 (N = 304), we tested whether it was better to conceptualize envy as being two separate emotions, benign envy and malicious envy. A significant effect of malicious envy was found (β = 0.13) and no significant effect of benign envy (β = ?0.06). Study 3 (N = 501) closely replicated this improved model, confirming significant effects of compassion (β = 0.40), self-interest (β = 0.21), and malicious envy (β = 0.15), accounting for one third of variance in support for redistribution. These results support the role of evolved motivational systems to explain and improve important aspects of contemporary economic redistribution. 相似文献
11.
A high-resolution electron microscopy study of nucleosomes from simian virus 40 chromatin 总被引:4,自引:0,他引:4
The DNA sequence changes of 31 mutations altering the attenuation control mechanism of the histidine operon are presented. These mutations are discussed in terms of a model for operon regulation that involves a his leader peptide gene whose translation regulates formation of alternative stem-loop structures in the his leader messenger RNA. Three suppressible mutations generate nonsense codons (ochre and UGA) in the his leader peptide gene, demonstrating that translation of this gene is essential for operon expression. Eight mutations presumably reduce the efficiency of translation initiation of the his leader peptide gene, causing reduced levels of operon expression. Five of these mutations directly alter the leader peptide gene initiator codon (AUG). Three mutations alter sequences just in front of the initiator codon and presumably alter the ribosome recognition site. Fourteen mutations reduce the stability of the his leader mRNA stem-loop structures that are alternatives to the attenuator stem. The properties of these mutations provide support for the role of these stem-loop structures in preventing formation of the attenuator stem. Finally, we show that mutations that alter the attenuator stem suppress hisO mutations. This lends support to the proposal that these hisO mutations cause reduced levels of operon expression due to excessive attenuator stem formation. The properties of these 31 mutations provide substantial support for the model of his operon regulation described in this paper. 相似文献
12.
Diego L. Salariato Fernando O. Zuloaga Ihsan A. Al-Shehbaz 《Plant Systematics and Evolution》2012,298(10):1961-1976
Previous systematic treatments of Menonvillea recognized a group of six morphologically related species, the ‘M. scapigera group,' distinguished by having pinnately lobed leaves and united filaments of median staminal pairs. The number of recognized species ranged from six to two, one with three subspecies. In order to clarify the taxonomy of this group, multivariate and univariate analyses of qualitative and quantitative characters from herbarium specimens were performed. Additionally, to test the morphological results, the phylogenetic relationships and degree of exclusive ancestry were studied using ITS sequences and the genealogical sorting index. Our results support the recognition of three species (M. famatinensis, M. hirsuta, M. scapigera) delimited by a unique combination of qualitative characters. Quantitative characters support the division of the latter species into two subspecies: scapigera and longipes. The molecular data are congruent with the morphology and support the inclusion of M. hookeri within M. scapigera. A key to taxa of the M. scapigera group is presented. 相似文献
13.
C.G. van Ginkel J. Tramper K.Ch.A.M. Luyben A. Klapwijk 《Enzyme and microbial technology》1983,5(4):297-303
Nitrosomonas europaea cells have been immobilized in calcium alginate and the resulting preparation was used as a biocatalyst for the oxidation of NH+4 to NO?2. Characterization of this immobilized biocatalyst was done according to the guidelines recommended by the Working Party on Immobilized Biocatalysts of the European Federation of Biotechnology. The most important indications obtained from the results are: (a) at low concentrations of substrate, either ammonium ions or oxygen, diffusion limitation will play a role; (b) inhibition by nitrite ions accumulating in the support is not rapidly controlling the efficiency of the immobilized cells; (c) accumulation of hydrogen ions is a rate-limiting factor, especially in unbuffered solutions; (d) the activity of immobilized N. europaea can increase as a result of growth in the support under conditions which would cause washout of free cells. This last result shows the potential of immobilized N. europaea for nitrification of wastewater. The development of a system applying a cheaper and more stable support is, however, a prerequisite for this application. 相似文献
14.
15.
Objective
The aim of this study was to investigate the association between social support and AIDS high-risk behaviors in commercial sex workers (CSWs) in China.Methods
A cross-sectional study was performed based on a convenience sample. Data were collected through questionnaire interviews including information about social demographic characteristics, the Social Support Rating Scale (SSRS) and AIDS knowledge. Multiple logistic regression was performed to evaluate the association between social support and AIDS high-risk behaviors, specifically condom use during commercial sex.Results
A total of 581 commercial sex workers from 4 counties in East China participated in the study. The majority of the participants were 15 to 30 years old (79.7%). Sources of individual and family support were mainly provided by their parents (50.3%), relatives and friends (46.3%), spouses (18.4%), respectively. Univariate analysis revealed that marital status, hobbies, smoking habit, individual monthly income and family monthly income were all significantly correlated with current levels of social support being received (P = 0.04, P = 0.00, P = 0.01, P = 0.01, P = 0.01, respectively). Furthermore, Multiple logistic regression analysis indicated that after adjusting for confounding factors, high levels of social support were significantly correlated with increased condom use at the last sexual encounter (P = 0.02, OR = 1.86, 95%CI: 1.10–3.16); and consistently in the past month with clients (P = 0.03, OR = 2.10, 95%CI: 1.09–4.04).Conclusion
CSWs with high levels of social support are more likely to use condoms during commercial sex. This suggests that increasing social support can potentially reduce AIDS-related high-risk behaviors and accordingly play an important role in AIDS prevention. 相似文献16.
Johnsson R Lackey JG Bogojeski JJ Damha MJ 《Bioorganic & medicinal chemistry letters》2011,21(12):3721-3725
We report on the synthesis and properties of oligonucleotides containing 2′-O-(levulinic acid) and 2′-O-(amino acid) acetalesters. Given that esters serve as promoieties in several therapeutic prodrugs, we believe that these derivatives will have potential use as nucleic acid prodrugs. In addition, we report on the synthesis of a novel solid support with a photolabile linker that not only allows for the synthesis of oligonucleotides containing various 2′-O-acetalesters, but can be generally adopted to the synthesis of base-sensitive oligoribonucleotides. The release of oligonucleotides from this support is faster than with conventional linkers. 相似文献
17.
Fetal calf serum (FCS) is unique among mammalian sera in its ability to support a primary antibody response, in vitro, by murine spleen cells. Another property unique to FCS among mammalian sera is its content of the tripeptide, glutathione. Since glutathione has a number of physiological functions important to cell function and survival, we have studied the possible relationship between the glutathione content of FCS and the ability of FCS to support a primary antibody response, in vitro. Our findings indicate that the capacity of FCS to support the murine spleen cell primary antibody response, in vitro, is, in part a function of its reduced glutathione (GSH) content, since: (a) GSH concentration correlates directly and definitively with the capacity of a lot of FCS to support an antibody response; (b) oxidation of GSH by heating a supportive FCS diminishes the supportive capacity of that FCS; and (c) such a treated FCS can be reconstituted to full supportiveness by appropriate doses of GSH. We postulate that reduced glutathione achieves this effect by scavenging lipid hydroperoxides generated by the action of oxygen-derived free radicals in the cell cultures. 相似文献
18.
Vigorous Mold Growth in Soils After Addition of Water-Insoluble Fatty Substances 总被引:1,自引:1,他引:0
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Various water-insoluble fatty compounds, when added to soil in finely divided form, will support as high-caloric nutrients a visible, vigorous growth of the molds, Fusarium solani Mart., F. diversisporum Sherb., and F. equiseti. n-Paraffins and olefins are most effective, because the effect of additives is reduced to the extent that oxygen atoms are introduced into the molecule. n-Fatty alcohols support growth in soil almost as well as the paraffins; however, growth is reduced when branched-chain compounds are added as nutrients. Compounds that will support mold growth when added to air-dried soil as finely powdered solids will not do so when incorporated at temperatures above their melting point, but will produce dense growth when applied to wet soil in this form. Mold growth is correlated with degradation of fatty matter. The rate of degradation is controlled by the availability of water, oxygen, and the basic inorganic nutrients. 相似文献
19.
The founding heterochronic microRNAs, lin-4 and let-7, together with their validated targets and well-characterized phenotypes in C. elegans, offer an opportunity to test functionality of microRNAs in a developmental context. In this study, we defined sequence requirements at the microRNA level for these two microRNAs, evaluating lin-4 and let-7 mutant microRNAs for their ability to support temporal development under conditions where the wild-type lin-4 and let-7 gene products are absent. For lin-4, we found a strong requirement for seed sequences, with function drastically affected by several central mutations in the seed sequence, while rescue was retained by a set of mutations peripheral to the seed. let-7 rescuing activity was retained to a surprising degree by a variety of central seed mutations, while several non-seed mutant effects support potential noncanonical contributions to let-7 function. Taken together, this work illustrates both the functional partnership between seed and non-seed sequences in mediating C. elegans temporal development and a diversity among microRNA effectors in the contributions of seed and non-seed regions to activity. 相似文献
20.
Yi Yin Weijun Zhang Zhenyu Hu Fujun Jia Yafang Li Huiwen Xu Shuliang Zhao Jing Guo Donghua Tian Zhiyong Qu 《PloS one》2014,9(9)
In China, caregivers for family members with schizophrenia play an important role in treatment and recovery but may experience stigma and discrimination simply because of their family relationship. The object of this study was to measure the degrees and correlates of stigma and discrimination experiences among this group. Four hundred twenty-seven caregivers participated in this hospital-based and cross-sectional study in Ningbo and Guangzhou, China. Data were collected by trained interviewers using fixed questionnaires. Stigma and discrimination experiences were measured by the Modified Consumer Experiences of Stigma Questionnaire (MCESQ). Caregivers’ social support was measured by the Social Support Rating Scale. Parametric analysis, nonparametric analysis and multivariate linear regression were used. The mean (SD) score of MCESQ was 2.44(0.45), 2.91(0.71) for stigma experiences and 1.97(0.37) for discrimination experiences on a five-point score (“1 = never” and “5 = very often”). Approximately 65% of caregivers reported that they tried to conceal their family members’ illness, and 71% lacked the support of friends. The experience of stigma was significantly negatively associated with the perceived social support of caregivers (standard β = −0.2,p<0.001). Caregivers who were children of the patients experienced fewer stigmas than other (standard β = −0.18, p<0.001). Urban residence (standard β = −0.12, p<0.01) and patients did not complete primary school education (standard β = −0.13, p<0.01) were negatively related with stigmas. In addition, stigma and discrimination was more experienced in Zhejiang than in Guangdong (p<0.05). In conclusion, this study performed that caregivers of people with schizophrenia in China experienced general stigmas and rare discrimination and found the relations with social support, kinship, patient’s educational level and regional differences. More interventions and supports should been given to caregivers who are lack of social support, who live in rural area and who are the patients’ parents, spouses or siblings. 相似文献