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Several studies have suggested that maternal lifestyle during pregnancy may influence long-term health of offspring by altering the offspring epigenome. Whether maternal leisure-time physical activity (LTPA) during pregnancy might have this effect is unknown. The purpose of this study was to determine the relationship between maternal LTPA during pregnancy and offspring DNA methylation. Participants were recruited from the Archive for Research on Child Health study. At enrollment, participants’ demographic information and self-reported LTPA during pregnancy were determined. High active participants (averaged 637.5 min per week of LTPA; n=14) were matched by age and race to low active participants (averaged 59.5 min per week LTPA; n=28). Blood spots were obtained at birth. Pyrosequencing was used to determine methylation levels of long interspersed nucleotide elements (LINE-1) (global methylation) and peroxisome proliferator-activated receptor-gamma (PPARγ), peroxisome proliferator-activated receptor-gamma coactivator (PGC1-α), insulin-like growth factor 2 (IGF2), pyruvate dehydrogenase kinase, isozyme 4 (PDK4) and transcription factor 7-like 2 (TCF7L2). We found no differences between offspring of high active and low active groups for LINE-1 methylation. The only differences in candidate gene methylation between groups were at two CpG sites in the P2 promoter of IGF2; the offspring of low active group had significantly higher DNA methylation (74.70±2.25% methylation for low active v. 72.83±2.85% methylation for high active; P=0.045). Our results suggest no effect of maternal LTPA on offspring global and candidate gene methylation, with the exception of IGF2. IGF2 has been previously associated with regulation of physical activity, suggesting a possible role of maternal LTPA on regulation of offspring physical activity.
When 14C signals approach background levels, the validity of assumptions concerning Poisson counting statistics and measurement system stability becomes crucial in interpreting the resultant low-level counting observations. This has been demonstrated in our previous work on detection limits for non-Poisson error and it is critical in our current studies of carbonaceous pollutants, where the 14C signal from just 5 mg C is comparable to that of the background for our miniature gas proportional counters. To assure data quality, our multi-detector system is designed for the on-line monitoring of critical parameters that reflect both the (statistical) nature of the non-Poisson errors and the underlying (physical) causes. It sends >60 bits of information/pulse to a microprocessor which automatically generates, for each counting period, two-dimensional spectra and multiparameter correlation and control charts. To evaluate the validity of long-term counting of 1–10 mg C we use robust (statistical) estimators, optimal counting interval subdivision, and time series analysis of the individual pulses. New opportunities for selective sampling and chemical fractionation which come with the small sample measurement capability have led us to give special attention also to higher control levels, involving e g, isotonic heterogeneity and representative standard materials.
Previous studies of the dimensional structure of panic attack symptoms have mostly identified a respiratory and a vestibular/mixed somatic dimension. Evidence for additional dimensions such as a cardiac dimension and the allocation of several of the panic attack symptom criteria is less consistent. Clarifying the dimensional structure of the panic attack symptoms should help to specify the relationship of potential risk factors like anxiety sensitivity and fear of suffocation to the experience of panic attacks and the development of panic disorder.
In an outpatient multicentre study 350 panic patients with agoraphobia rated the intensity of each of the ten DSM-IV bodily symptoms during a typical panic attack. The factor structure of these data was investigated with nonlinear confirmatory factor analysis (CFA). The identified bodily symptom dimensions were related to panic cognitions, anxiety sensitivity and fear of suffocation by means of nonlinear structural equation modelling (SEM).
CFA indicated a respiratory, a vestibular/mixed somatic and a cardiac dimension of the bodily symptom criteria. These three factors were differentially associated with specific panic cognitions, different anxiety sensitivity facets and suffocation fear.
Taking into account the dimensional structure of panic attack symptoms may help to increase the specificity of the associations between the experience of panic attack symptoms and various panic related constructs.
The aim of this study was to determine heritability estimates of treatment responses to a 10% hydrogen peroxide strip-based whitening system in twins. Eighty-five twin pairs were randomly assigned to 10% hydrogen peroxide whitening strips or placebo strips without peroxide. Both twins (monozygotic or dizygotic) received the same treatment. Maxillary teeth were treated for 30 minutes twice daily for 7 days. Efficacy was measured objectively as L* (light–dark), a* (red–green), and b* (yellow–blue) color change from digital images at baseline (∆) and day 8. Heritability estimates for tooth whitening treatment responses for changes from day 8 to baseline were obtained using variance-component methodologies. Whitening treatment responses were highly heritable (h2 = 71.0) for ∆b* and ∆a*(p < .0001), but not for ∆L* (h2 = 27.0), which was essentially modulated by environmental factors. This study has demonstrated that both genetic and environmental factors significantly contributed to seven-day whitening treatment responses achieved with 10% hydrogen peroxide strips.
Panic disorder with agoraphobia is characterized by panic attacks and anxiety in situations where escape might be difficult. However, neuroimaging studies specifically focusing on agoraphobia are rare. Here we used functional magnetic resonance imaging (fMRI) with disorder-specific stimuli to investigate the neural substrates of agoraphobia.
We compared the neural activations of 72 patients suffering from panic disorder with agoraphobia with 72 matched healthy control subjects in a 3-T fMRI study. To isolate agoraphobia-specific alterations we tested the effects of the anticipation and perception of an agoraphobia-specific stimulus set. During fMRI, 48 agoraphobia-specific and 48 neutral pictures were randomly presented with and without anticipatory stimulus indicating the content of the subsequent pictures (Westphal paradigm).
During the anticipation of agoraphobia-specific pictures, stronger activations were found in the bilateral ventral striatum and left insula in patients compared with controls. There were no group differences during the perception phase of agoraphobia-specific pictures.
This study revealed stronger region-specific activations in patients suffering from panic disorder with agoraphobia in anticipation of agoraphobia-specific stimuli. Patients seem to process these stimuli more intensively based on individual salience. Hyperactivation of the ventral striatum and insula when anticipating agoraphobia-specific situations might be a central neurofunctional correlate of agoraphobia. Knowledge about the neural correlates of anticipatory and perceptual processes regarding agoraphobic situations will help to optimize and evaluate treatments, such as exposure therapy, in patients with panic disorder and agoraphobia.
The introduction of the ‘western diet’ marked a decline in omega–3 fatty acids rich foods and a concurrent increase in saturated and omega–6 fatty acids that persists today. Historically, circumpolar people have had a low incidence of obesity, diabetes and cardiovascular disease and this has been largely attributed to polyphenolic compounds and omega–3 fatty acids offered from subsistence foods. In this report, we studied sled dogs as an Arctic sentinel species for monitoring the effect of a changing diet on lipid profiles along the Yukon River. Subsistence fed village sled dogs along the Yukon River, maintained largely on salmon were compared with a control kennel maintained on commercial food. Profiles showed higher levels for long chain omega–3 fatty acids in village subsistence fed dogs compared to control dogs and an opposite trend for omega–6 fatty acids, establishing baseline levels for follow up studies. A comparison with data for previously published mercury levels from the same cohort of dogs revealed a positive correlation with alpha–linolenic fatty acid and a negative correlation with linoleic fatty acid. Food and nutritional security is a concern in the Arctic as the impacts of climate change and transport of contaminants become obvious. This study supports not only the nutritional value of a subsistence diet but also the utility of sled dogs as a sentinel for human dietary change.
Thin films of aromatic polymers such as polyimide (PI) and polyethersulfone (PES) find an extensive use in aerospace and electronic applications, in particular, as sensitive to moisture and gas uptake layers for bimorphic sensors. In this work, a complex investigation of the film composition, microstructure and physical properties of ion beam modified polymer films was carried out to optimize the moisture uptake. To modify thin films of polyimide and polyethersulfone 50, 130 and 180 keV boron ions with irradiation doses between 1013 and 1016 B+/cm2 were implanted. It could be shown, that partly destruction of chemical bonding under ion bombardment leads to the creation of new amorphous and graphite-like structures, which increase the modified surface film conductivity by several orders of magnitude and enhances the sensitivity of these nanocomposite films to moisture uptake.
Japan's economy has long been described as network-centric. A web of stable, reciprocated relations among banks, firms, and ministries, is thought to play an important role in Japan's ability to navigate smoothly around economic shocks. Now those networks are widely blamed for Japan's faltering competitiveness. This book applies structural sociology to a study of how the form and functioning of this network economy has evolved from the prewar era to the late 90s. It asks whether, in the face of deregulation, globalization, and financial disintermediation, Japan's corporate networks - the keiretsu groupings particularly - have 'withered away', losing their cohesion and their historical function of supporting member firms in hard times. Using detailed quantitative and qualitative analysis, this book's conclusion is a qualified 'yes'. Relationships remain central to the Japanese way of business, but are much more subordinated to the competitive strategy of the enterprise than the network economy of the past.
Japan is going through its biggest social upheaval since the Meiji Restoration.
Masayoshi Son, founder and CEO, Softbank Corporation.
As to what degree the network structure of the Japanese economy has withered away, our analysis from the 1960s to the 1990s yields a mixed picture. Signs of disintegration abound — in the fabric of the corporate network as a whole, in the boundedness and coherence of individual keiretsu groupings, and in the general decline of redistributive intervention to align and smooth the growth and profitability trajectories of affiliated firms. Yet the indications are also substantial that, at odds with the recent conventional wisdom, the recessionary 1990s were to some degree a time of retrenchment, not abandonment, of dense networks, keiretsu forms, and performance alignment. This pattern, we think, comports with the core function that keiretsu serve: as mutual support networks that sustain member firms through difficult times. Critics, however, argue that the system of risk-sharing and reciprocal obligation is the reason that the Japanese economy got in trouble in the first place and is having such difficulty extricating itself from bad times. The Economist (2002), ever critical of Japan's network economy, noted:
According to Goldman Sachs, as of November 5th, the share price of only 60 of the more than 1,400 companies currently listed on the first section of the Tokyo Stock Exchange had risen at all since the start of 1990. … What sets such companies apart? … Most of them … have high levels of foreign ownership. … Many are also considered to have above-average standards of corporate governance. …[…]
Whereas the conventional view has tended to regard keiretsu affiliations and the subcontracting relationship as remnants of feudalistic relations or derivatives of the cultural peculiarities of the Japanese, the most important explanatory variable should be the kind and nature of the transaction of goods or services conducted beneath each of these relations. …[T]he fundamental link between a pair of firms should be located in … the resource flow … between them. To regulate this flow, a control apparatus is formed between the firms, the possible mode of which ranges from simple contract to a very complex and developed structure. The elaborateness of the control apparatus depends on the composition and the nature of the flow; the most developed type along this spectrum may have shareholding as its superstructure.
A criticism that might fairly be made of our network analysis in the last chapter is that it ignores the causality between lending and trade on the one hand and equity and director ties on the other. An alternative approach is to draw on organizational theory to model the cause-and-effect relationships between exchange and control and between them and attributes of firms such as industry, size, and location. Such an analysis, as the quote from Asanuma suggests, might well reveal that the concept of “keiretsu” adds little to an understanding of how firms vary in their involvement in business networks.
The organization of Japanese and Western industry was probably more similar in 1910 than in 1970.
Rodney Clark, 1979:258
As the first non-Western country to industrialize, Japan is an important test case for alternative models of economic development. While knowledgeable observers may disagree on the specifics, most will concur with the premise that Japan's development was not simply the product of convergent modernization — its economic, political, and social institutions reflect distinctive features of Japan's own history, not merely the re-creation of their Western counterparts. Indeed, as Clark suggests in the introductory quote, the general trend through much of this century may have been toward divergence away from Western (or at least American) assumptions about how development takes place.
This chapter considers the issue of Japan's economic development from an institutionally informed network perspective by exploring the organizational and industrial arrangements that have underpinned it. Our methodology, unlike the quantitative analyses in chapters to follow, is qualitative and historical, covering a period of roughly a century from the early years of Japan's modernization in the late 1800s to the miracle years of the 1950s to 1980s. Our treatment is focused and analytical rather than exhaustive and descriptive. A few underlying principles explain much of what we see today, even if the specifics have varied by time period, industry, and company.
We divide the evolution of Japanese network organization into three phases of development.
The network idea has become a central metaphor in our daily lives. We talk of networking as a way to advance a career or gain political leverage. We refer to the breadth, density, and connectivity of someone's network as social capital that has real productive value and can be cultivated and deployed. With the fusion of computer and communications technology in the Internet have come significant new forms of social and economic organization as organizational and geographic boundaries dissolve in unbounded cyberspace. The drift toward network thinking has also broadly shaped the business world, as companies everywhere are forced to rethink not only their own relationships with suppliers, customers, banks, shareholders, and other stakeholders, but the relations among these as well. In some industries, firms are forging alliances with competitors and across industries in order to exploit market opportunities offered by new technologies. In others, the scale and scope of business activities has grown so broad that no firm can handle all the steps of the production process and firms cooperate simply to survive.
Nowhere is the importance of network thinking more evident than in Japan. As an emerging social science literature contends, the constitutive tissue of Japanese society is the formal and informal relationships that span all walks of daily life, from local community to political arena to economic sphere.
The network metaphor has become increasingly popular with social scientists; it has even penetrated the conservative precincts of economics. … [A]ttempts to develop the metaphor into operational concepts have taken two directions. One has emphasized the paths or “threads” in a single network: the manner in which long chains of contact wind their way through large social systems. … The second has emphasized the “knittedness” of interconnections within a network and the overlaps between multiple (many-stranded) types of networks for a given population.
White, Boorman, and Breiger, 1976:730
Some 25 years after the publication of White, Boorman, and Breiger's classic paper on blockmodeling, most uses of the network idea in economic and organizational research remain metaphoric. They convey a quality of fluidity, permeability, even embeddedness in a set of relationships, but are typically silent on how one might measure and analyze such properties in testing hypotheses about network causes and consequences. This chapter offers a quantitative analysis of structural change in Japan's corporate network. We use some well-known methods of formal network analysis to map the evolution of business networks in Japan from longitudinal data on the country's largest financial institutions, trading companies, and industrial corporations. We will see that, to an extraordinary degree, Japanese economic organization in a network sense was built around keiretsu clusterings. Second, consistent with much recent commentary, this structure has eroded over time. Yet the decline has not been even or continuous.