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91.
In daily life, perceivers often need to predict and interpret the behavior of group agents, such as corporations and governments. Although research has investigated how perceivers reason about individual members of particular groups, less is known about how perceivers reason about group agents themselves. The present studies investigate how perceivers understand group agents by investigating the extent to which understanding the ‘mind’ of the group as a whole shares important properties and processes with understanding the minds of individuals. Experiment 1 demonstrates that perceivers are sometimes willing to attribute a mental state to a group as a whole even when they are not willing to attribute that mental state to any of the individual members of the group, suggesting that perceivers can reason about the beliefs and desires of group agents over and above those of their individual members. Experiment 2 demonstrates that the degree of activation in brain regions associated with attributing mental states to individuals—i.e., brain regions associated with mentalizing or theory-of-mind, including the medial prefrontal cortex (MPFC), temporo-parietal junction (TPJ), and precuneus—does not distinguish individual from group targets, either when reading statements about those targets'' mental states (directed) or when attributing mental states implicitly in order to predict their behavior (spontaneous). Together, these results help to illuminate the processes that support understanding group agents themselves. 相似文献
92.
Higher expression of induced defenses in teosintes (Zea spp.) is correlated with greater resistance to fall armyworm,Spodoptera frugiperda 总被引:1,自引:0,他引:1
Adrianna Szczepaniec Sarah E. Widney Julio S. Bernal Micky D. Eubanks 《Entomologia Experimentalis et Applicata》2013,146(2):242-251
Selection for plant traits important for agriculture can come at a high cost to plant defenses. While selecting for increased growth rate and yield, domestication and subsequent breeding may lead to weakened defenses and greater susceptibility of plants to herbivores. We tested whether expression of defense genes differed among maize, Zea mays ssp. mays L. (Poaceae), and its wild relatives Zea mays ssp. parviglumis Iltis & Doebley and Zea diploperennis Iltis et al. We used two populations of Z. mays ssp. parviglumis: one expected to express high levels of an herbivore resistance gene, wound‐inducible protein (wip1), and another expected to have low expression of wip1. To test whether maize and wild Zea differed in induction of defenses against Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), we quantified expression of several genes involved in plant defense: wip1, maize protease inhibitor (mpi), pathogenesis‐related protein (PR‐1), and chitinase. Moreover, we compared growth, development, and survival of caterpillars on maize and wild Zea plants. We found that maize expressed low levels of all but one of the genes when attacked by caterpillars, whereas the wild relatives of maize expressed induced defense genes at high levels. Expression of wip1, in particular, was much greater in the Z. mays ssp. parviglumis population that we expected to naturally express high levels of wip1, with expression levels 29‐fold higher than in herbivore‐free plants. Elevated expression of defenses in wild plants was correlated with higher resistance to caterpillars. Larvae were 15–20% smaller on wild Zea compared with maize, developed 20% slower, and only 22% of them survived to pupation on Z. mays ssp. parviglumis with high levels of wip1. Our results suggest that domestication has inadvertently reduced the resistance of maize, and it is likely that expression of wip1 and other genes associated with defenses play an important role in this reduction in resistance. 相似文献
93.
94.
Preventing horticultural introductions of invasive plants: potential efficacy of voluntary initiatives 总被引:1,自引:0,他引:1
Jennifer W. Burt Adrianna A. Muir Jonah Piovia-Scott Kari E. Veblen Andy L. Chang Judah D. Grossman Heidi W. Weiskel 《Biological invasions》2007,9(8):909-923
Although prevention is the most cost-effective way to avoid the enormous expenses associated with plant invasions, invasive
plants continue to be imported as trade commodities for horticultural use. With very little government regulation of horticultural
imports of invasive plants, efforts have turned toward fostering voluntary initiatives to encourage self-regulation by the
horticulture trade. Our study takes the first step toward evaluating the potential success of these voluntary initiatives.
We conducted a survey of nursery professionals to gauge their perceptions of invasive species, the role of the horticulture
trade in invasive plant introductions, and their participation—potential and actual—in preventive measures outlined in the
St Louis Voluntary Codes of Conduct for nursery professionals. We found nursery professionals to be highly aware of invasive
plants and to accept responsibility as a trade for horticultural introductions. Although only 7% of respondents had heard
of the St Louis Voluntary Codes of Conduct, the majority (57%) reported having participated in at least two of seven preventive
measures, and most (78%) reported willingness to engage in the majority of preventive measures. We found that several factors
significantly predict increased participation in preventive measures, particularly awareness of invasive plants and involvement
in trade associations. We also identified incentives and obstacles to participating in preventive behaviors, including “concern
for the environment” and “lack of information,” respectively. Our results suggest that participation in voluntary initiatives
will improve through increased outreach, and we provide specific recommendations for improving participation in voluntary
programs in the horticulture trade. 相似文献
95.
Skoneczna A McIntyre J Skoneczny M Policinska Z Sledziewska-Gojska E 《Journal of molecular biology》2007,366(4):1074-1086
Saccharomyces cerevisiae Rad30 is the homolog of human DNA polymerase eta whose inactivation leads to the cancer-prone syndrome xeroderma pigmentosum variant. Both human and yeast polymerase eta are responsible for error-free bypass of UV-induced cis-syn pyrimidine dimers and several other DNA lesions. Here we show, using yeast strains expressing TAP-tagged Rad30, that the level of this protein is post-translationally regulated via ubiquitination and proteasome-mediated degradation. The half-life of Rad30 is 20 min and it increases due to proteasomal defects. Mutations inactivating components of the Skp1/cullin/ F-box (SCF) ubiquitin ligase complex: Skp1 and the F-box protein Ufo1 stabilize Rad30. Our results indicate also that ultraviolet irradiation causes transient stabilization of Rad30, which leads, in turn, to temporary accumulation of this polymerase in the cell. We conclude that proteolysis plays an important role in regulating the cellular abundance of Rad30. These results are the first indication of a role for controlled proteasomal degradation in modulating cellular level of translesion DNA polymerase in eukaryotes. 相似文献
96.
97.
Diatoms are ubiquitous and abundant primary producers that have been traditionally considered as a beneficial food source for grazers and for the transfer of carbon through marine food webs. However, many diatom species produce polyunsaturated aldehydes that disrupt development in the offspring of grazers that feed on these unicellular algae. Here we provide evidence that production of the physiological messenger nitric oxide increases after treatment with the polyunsaturated aldehyde decadienal in embryos of the sea urchin Paracentrotus lividus. At high decadienal concentrations, nitric oxide mediates initial apoptotic events leading to loss of mitochondrial functionality through the generation of peroxynitrite. At low decadienal concentrations, nitric oxide contributes to the activation of hsp70 gene expression thereby protecting embryos against the toxic effects of this aldehyde. When nitric oxide levels were lowered by inhibiting nitric oxide synthase activity, the expression of hsp70 in swimming blastula decreased and the proportion of abnormal plutei increased. However, in later pluteus stages nitric oxide was no longer able to exert this protective function: hsp70 and nitric oxide synthase expression decreased with a consequent increase in the expression of caspase-8. Our findings that nitric oxide production increases rapidly in response to a toxic exogenous stimulus opens new perspectives on the possible role of this gas as an important messenger to environmental stress in sea urchins and for understanding the cellular mechanisms underlying toxicity during diatom blooms. 相似文献
98.
Huffman MD Rao KD Pichon-Riviere A Zhao D Harikrishnan S Ramaiya K Ajay VS Goenka S Calcagno JI Caporale JE Niu S Li Y Liu J Thankappan KR Daivadanam M van Esch J Murphy A Moran AE Gaziano TA Suhrcke M Reddy KS Leeder S Prabhakaran D 《PloS one》2011,6(6):e20821
Objective
To estimate individual and household economic impact of cardiovascular disease (CVD) in selected low- and middle-income countries (LMIC).Background
Empirical evidence on the microeconomic consequences of CVD in LMIC is scarce.Methods and Findings
We surveyed 1,657 recently hospitalized CVD patients (66% male; mean age 55.8 years) from Argentina, China, India, and Tanzania to evaluate the microeconomic and functional/productivity impact of CVD hospitalization. Respondents were stratified into three income groups. Median out-of-pocket expenditures for CVD treatment over 15 month follow-up ranged from 354 international dollars (2007 INT$, Tanzania, low-income) to INT$2,917 (India, high-income). Catastrophic health spending (CHS) was present in >50% of respondents in China, India, and Tanzania. Distress financing (DF) and lost income were more common in low-income respondents. After adjustment, lack of health insurance was associated with CHS in Argentina (OR 4.73 [2.56, 8.76], India (OR 3.93 [2.23, 6.90], and Tanzania (OR 3.68 [1.86, 7.26] with a marginal association in China (OR 2.05 [0.82, 5.11]). These economic effects were accompanied by substantial decreases in individual functional health and productivity.Conclusions
Individuals in selected LMIC bear significant financial burdens following CVD hospitalization, yet with substantial variation across and within countries. Lack of insurance may drive much of the financial stress of CVD in LMIC patients and their families. 相似文献99.
Pawlik P Mostowska A Lianeri M Sajdak S Kędzia H Jagodzinski PP 《Molecular biology reports》2012,39(5):5553-5560
Data indicates that genetic factors alone do not account for ovarian tumorigenesis, suggesting that epigenetic status additionally
affects this process. Therefore, we assessed the possible contribution of polymorphic variants of genes that may affect DNA
methylation to the risk of ovarian cancer incidence in the Polish population. Using PCR-RFLP and HRM analyses, we studied
the distribution of BHMT (rs3733890), MTHFD1 (rs2236225), MTHFR (rs1801133), MTR (rs1805087), MTRR (rs1801394) and TCN2 (rs1801198) genotypes and alleles in patients with ovarian cancer (n = 136) and controls (n = 160). Moreover, using DNA and methylation-specific PCR (MSP) we also determined the methylation of the Cadherin 13
(CDH13) promoter in cancerous tissue from these patients. We did not observe a significant association between all studied gene variants
and the incidence of ovarian cancer. The lowest P
trend = 0.1226 was observed for the MTHFR Ala222Val polymorphism. Moreover, the lowest P = 0.0772 was found in the comparison of MTHFR Ala/Ala versus Val/Val and Val/Ala genotypes in patients and control groups. The multifactor dimensionality reduction analysis
also did not indicate a significant interactive genetic effect on ovarian cancer incidence for all analyzed SNPs. However,
we observed frequent methylation of the CDH13 promoter in approximately 21% (29/136) patients with ovarian carcinomas. Our results might suggest that the selected polymorphic
gene variants may not contribute to ovarian cancer incidence. 相似文献
100.
Mostowska M Lianeri M Oko A Mostowska A Jagodziński PP 《Molecular biology reports》2012,39(5):5933-5941
Various studies have indicated that chemokines such as monocyte chemotactic protein-1 (MCP-1) play an important role in the
pathogenesis of primary glomerulonephritis (GN) and other glomerular diseases. Moreover, patients with primary GN display
aberrant galactosylation of the O-linked carbohydrate moieties of IgA. Therefore, we analysed the distribution of the functional
MCP-1 −2518 A > G (rs 1024611) and 1 beta 1,3-galactosyltransferase (C1GalT1) 1365 A > G (rs1047763) polymorphic variants in patients with primary GN (n = 144) and controls (n = 437) in a sample of the Polish population. We did not find a significant difference in the prevalence of the MCP-1 −2518
A > G and C1GalT1 1365 A > G polymorphisms in patients with primary GN and healthy individuals. Odds Ratio (OR) for GN patients with the MCP-1
−2518 GG genotype was 0.869 (95% CI = 0.410–1.840, P = 0.7130), and OR of the −2518 GG and −2518AG genotypes was 1.004 (95% CI = 0.689–1.464, P = 0.9836). OR for C1GalT1 1365AA genotype was 0.484 (95% CI = 0.181–1.293, P = 0.1402) and OR of the 1365AA and 1365AG genotypes was 0.839 (95% CI = 0.573–1.228, P = 0.3651). We also did not observe a difference in the distribution of alleles between patients and controls. The MCP-1 −2518
G allelic OR was 0.976 (95% CI = 0.725–1.314, P = 0.8744). The OR for the C1GalT1 1365A allele was 0.816 (95% CI = 0.596–1.118, P = 0.205). Moreover, there was no significant association between the MCP-1 −2518 A > G and C1GalT1 1365 A > G genotypes with different morphological types of primary GN or clinical manifestations. Our observations indicate
that the MCP-1 −2518 A > G and C1GalT1 1365 A > G polymorphisms might not be a risk factor in the incidence of primary GN in the Polish population. 相似文献