The effects of dietary polyunsaturated fatty acids (PUFA) on ex vivo bone prostaglandin E(2) (PGE(2)) production and bone formation rate were evaluated in rats. Weanling male Sprague-Dawley rats were fed AIN-93G diet containing 70 g/kg of added fat for 42 d. The dietary lipid treatments were formulated with safflower oil and menhaden oil to provide the following ratios of (n-6)/(n-3) fatty acids: 23.8 (SMI), 9.8 (SMII), 2.6 (SMIII), and 1.2 (SMIV). Ex vivo PGE(2) production in liver homogenates and bone organ cultures (right femur and tibia) were significantly lower in rats fed diets with a lower dietary ratio of (n-6)/(n-3) fatty acids than in those fed diets with a higher dietary ratio. Regression analysis revealed a significant positive correlation between bone PGE(2) and the ratio of arachidonic acid (AA)/eicosapentaenoic acid (EPA), but significant negative correlations between bone formation rate and either the ratio of AA/EPA or PGE(2) in bone. Activities of serum alkaline phosphatase isoenzymes, including the bone-specific isoenzyme (BALP), were greater in rats fed a diet high in (n-3) or a low ratio of (n-6)/(n-3), further supporting the positive action of (n-3) fatty acids on bone formation. These results demonstrated that the dietary ratio of (n-6)/(n-3) modulates bone PGE(2) production and the activity of serum BALP in growing rats.

No abstract

This study examined the effects of dietary fat on the fatty acid composition of liver and bone, and on the concentration of insulin-like growth factor-I (IGF-I) in liver and bone, as well as the relationship of these factors to bone metabolism. Day-old male broiler chicks were given a semipurified diet containing one of four lipid sources: soybean oil (SBO), butter+corn oil (BC), margarine+corn oil (MAC), or menhaden oil+corn oil (MEC) at 70 g/kg of the diet. At 21 and 42 d of age, chicks fed MEC had the highest concentration of (n-3) fatty acids [20:5(n-3), 22:5(n-3) and 22:6(n-3)] in polar and neutral lipids of cortical bone but the lowest amount of 20:4(n-6) in polar lipids. Diets containing t-18:1 fatty acids (MAC and BC) resulted in t18:1 accumulation in bone and liver. Bone IGF-I concentration increased from 21 to 42 d in chicks given the SBO and BC diets. Tibial periosteal bone formation rate (BFR) was higher in chicks given BC compared with those consuming SBO and MEC at 21 d. The higher BFR and concentrations of hexosamine in serum and IGF-I in cartilage, but lower 20:4(n-6) content in bone polar lipids in chicks given BC compared with those given SBO suggest that BC optimized bone formation by altering the production of bone growth factors. A second study confirmed that dietary butter fat lowered ex vivo prostaglandin E2 production and increased trabecular BFR in chick tibia. These studies showed that dietary fat altered BFR perhaps by controlling the production of local regulatory factors in bone.

Aspirations have been a key target of education policy, situated as central to meeting the needs of the ‘knowledge economy’. In the UK, there have been calls to raise young people’s aspirations for careers in the creative industries—identified as emblematic of the new economic order and a key growth sector. Yet, the sector is socially and spatially restricted, characterised by unclear entry routes, exclusionary working practices and uneven geographical concentration. This paper draws on research with young people (aged 14–16 years) living in three urban areas of deindustrialisation in England to examine the geography of young people’s aspirations for careers in the creative industries. The concept of place-specific habitus is used to problematise asocial and aspatial discourses of aspiration and to illuminate how social class and place powerfully and complexly interrelate to shape young people’s opportunities for social and geographical mobility through and for work in the knowledge economy.

Government attention (in England and elsewhere) has been drawn to the role of technology in supporting learning in families. However, sociologists of education highlight that parent's ability to engage with their children's education and learning is not a straightforward issue. Drawing on the work of Pierre Bourdieu, this paper attempts to open up a space for examination of the differential experiences of parents from different social class backgrounds, of technology in the home, and how this informs the potential they see for family learning using technology. We use Bourdieu's concepts of 'cultural and economic capital' and 'habitus' to explore several themes. Firstly, the paper explores the impact of material inequalities of access on families and how this structures parental engagement with technology in relation to their children's schooling; secondly, how the harms and risks of technology are differentially experienced, negotiated and managed by parents from different social class backgrounds -with varying amounts of social and cultural resources available to them; thirdly, through discussion of the 'generation gap', we examine the significance of the parents' working lives (in terms of the privileged forms of engagement with technology, which professional employment increasingly requires and facilitates) in shaping parents' own relationships to education and learning.

Preterm birth Is the most common cause of low Infant birth weight and Infant morbidity and mortality. Evidence from human and animal studies Indicates that essential fatty acids of both the n-3 and n-6 series, and their eicosanoid metabolites, play Important and modifiable rolesIn gestational duration and parturition, and n-a fatty acid Intake during pregnancy may be Inadequate. Prostaglandins (PO) of the 2-serles are Involved In parturition and connective tissue remodeling associated with cervical maturation and rupture of membranes. In the absence of Infections, preterm birth Is characterized by lowerreproductive tissue PO production and decreased Inducible cyclooxygenase expression. Women who deliver prematurely have Increased pools of n-s fatty acid and decreased n-3 fatty acids, despite the lower PO production. Several human pregnancy supplementation trials with n-a fatty acids have shown a significant reduction In the Incidence of premature deliverand Increased birthweightassociated with Increased gestational duration. Supplementation with longchainn-a fatty acidssuchas docosahexaenolc acidmaybe useful In prolonging the duration of gestation In somehigh-risk pregnancies. Evidence presented In this review Is discussed In terms of the roles of dietary n-a and n-6 fattyacidsIn gestation and parturition, mechanisms by which they may Influence gestational duration and the human trialssuggesting that Increased dietarylong-chain n-afattyae-Ids decrease the Incidence of premature delivery.

Attending to the biographical accounts of two participants occupying different class locations, I explore their transitions and perceptions of the uncertainties and risks characterising 'austere times'. I demonstrate how, despite similarities in their experiences of a stunted graduate labour market, social class shaped how they responded to and made sense of the pressures and predicaments they encountered.

Graduate outcomesincluding rates of employment and earningsare marked by persistent inequalities related to social class, as well as gender, ethnicity and institution. Despite national policy agendas related to social mobility and 'fair access to the professions', high-status occupations are disproportionately composed of those from socially privileged backgrounds, and evidence suggests that in recent decades many professions have become less socially representative. This paper makes an original contribution to sociological studies of inequalities in graduate transitions and elite reproduction through a distinct focus on the 'pre-hiring' practices of graduate employers. It does this through a critical analysis of the graduate recruitment material of two popular graduate employers. We show how, despite espousing commitments to diversity and inclusion, constructions of the 'ideal' graduate privilege individuals who can mobilise and embody certain valued capitals. Using Bourdieusian concepts of 'Social Magic' and 'Institutional Habitus' we argue that more attention must be paid to how graduate employers' practices constitute tacit processes of social exclusion and thus militate against the achievement of more equitable graduate outcomes and fair access to the 'top jobs'.