Book chapters will be unavailable on Saturday 24th August between 8am-12pm BST. This is for essential maintenance which will provide improved performance going forwards. Please accept our apologies for any inconvenience caused.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The present paper reviews the evidence as to whether patients on lipid-lowering drugs should restrict dietary SFA intake. Premature mortality from atherosclerotic CVD has fallen dramatically in many high-income countries. This appears to be due to a combination of improved treatment following a cardiovascular event and reduced risk factors, including LDL-cholesterol. Whether this reduction is due to changes in dietary habits, or the increasing availability of highly potent cholesterol-reducing drugs remains to be firmly established. While reducing dietary SFA intake has been the cornerstone of public health nutrition policy for several decades, the efficacy of such dietary changes has been challenged in recent years. While there remains a lack of consensus in the literature, there is an emerging view that dietary advice should be specifically modified to emphasise replacing SFA with PUFA in the diet rather than carbohydrate. The advice to moderate dietary SFA intake given to the general population is usually also given to those individuals at high risk of CVD who are prescribed lipid-lowering drugs. There is limited evidence to suggest that any potential benefit of such a diet on LDL-cholesterol may be offset by a concurrent decrease in HDL-cholesterol. However, as diets rich in SFA are frequently energy-dense, and rich in red and processed meat (potential risk factors for CVD in themselves), it would seem prudent to continue to advise patients on lipid-lowering drugs to maintain a low-fat diet.
The problem of financial stability is political and institutional, rather than narrowly economic. To achieve a more resilient financial system, we need to pay attention to the incentives of actors who have the power to act discretionarily, and to the knowledge limitations of such actors in the face of substantial complexity and uncertainty. The literature on polycentric governance and institutional resilience provides key insights that the literature on financial stability has thus far neglected. We offer an analysis based on the “design principles” for robust governance institutions proposed by Nobel laureate Elinor Ostrom. We apply these principles to banking systems and explore under what conditions a banking system can be expected to discover rules that align private incentives with broader financial stability, and generate the necessary knowledge to govern such a complex system. This perspective challenges both “microprudential” and “macroprudential” approaches, which assume a monocentric financial and banking regulator.
Background: Heterozygous loss-of-function mutations in the synaptic scaffolding gene SHANK2 are strongly associated with autism spectrum disorder (ASD). However, their impact on the function of human neurons is unknown. Derivation of induced pluripotent stem cells (iPSC) from affected individuals permits generation of live neurons to answer this question. Methods: We generated iPSCs by reprogramming dermal fibroblasts of neurotypic and ASD-affected donors. To isolate the effect of SHANK2, we used CRISPR/Cas9 to knock out SHANK2 in control iPSCs and correct a heterozygous nonsense mutation in ASD-affected donor iPSCs. We then derived cortical neurons from SOX1+ neural precursor cells differentiated from these iPSCs. Using a novel assay that overcomes line-to-line variability, we compared neuronal morphology, total synapse number, and electrophysiological properties between SHANK2 mutants and controls. Results: Relative to controls, SHANK2 mutant neurons have increased dendrite complexity, dendrite length, total synapse number (1.5-2-fold), and spontaneous excitatory postsynaptic current (sEPSC) frequency (3-7.6-fold). Conclusions: ASD-associated heterozygous loss-of-function mutations in SHANK2 increase synaptic connectivity among human neurons by increasing synapse number and sEPSC frequency. This is partially supported by increased dendrite length and complexity, providing evidence that SHANK2 functions as a suppressor of dendrite branching during neurodevelopment.
Gene insertion into the avian germ line is reviewed. Useful pathogen-derived and animal-derived resistance genes that could be inserted into the avian germ line to convey resistance to pathogens are discussed. Methods of germ line insertion that have been successful in mice are summarized and their possible application in future avian germ line research are described. The successful transfer of retroviral genes into the chicken germ line using replication-competent recombinant retroviruses is summarized and several potentially useful transgenic chicken lines are described. The attempts to use one-round replication-defective retroviral vectors have been complicated by the detection of replication-competent retrovirus in chicks from injected eggs.
The correlation between ATP concentration and bacterial burden in the patient care environment was assessed. These findings suggest that a correlation exists between ATP concentration and bacterial burden, and they generally support ATP technology manufacturer-recommended cutoff values. Despite relatively modest discriminative ability, this technology may serve as a useful proxy for cleanliness.
Adipose tissue becomes more saturated and less unsaturated with age (Kemp et al., 1981). Desaturation of stearic acid to the oleic acid is catalysed by stearoyl-CoA desaturase (SCD) and increasing the degree of desaturation of lamb is likely to be beneficial in terms of human nutrition. By altering the levels of ovine SCD mRNA, the supply of oleic acid to the tissue could be manipulated, resulting in a practical method of changing the fatty acid profile of the animals meat. Previous work in our laboratory has shown variability between adipose tissue depots in their expression of SCD and that this variability is associated with changes in oleic acid content (Daniel et al, 2004). Such differences in SCD expression between depots implies that there may be even larger variation in SCD expression between breeds. A sheep breed with particularly high level of SCD mRNA could then be exploited through breeding programmes to produce animals with increased desaturase activity and therefore increased oleic acid content. Three sheep breeds, Texel, Beulah and Soay, were therefore used to study the influence of breed and age on SCD expression.
In 1991 it was recommended that total fat intake in the UK should be reduced to a population average of less that 33% of total daily energy intake and that saturated fatty acids should contribute no more than 10% of total energy (Department of Health, 1991). A further recommendation was that the intake of trans fatty acids should not exceed 2% of total energy. These recommendations were made primarily on the basis of the influence of fatty acids on plasma cholesterol and thereby on the development of cardiovascular disease. While associations of fat intake with other chronic diseases such as cancer, obesity and diabetes have also been suggested, it was felt that there was insufficient evidence to make specific recommendations on the basis of such claims. A reduction in saturated fat intake has remained a central target of public health nutrition within the United Kingdom ever since. Despite concerted efforts, particularly throughout the 1990s., to achieve these targets little progress has been made. In 2000, total fat intake remained at 38% and saturated fatty acid intake at 15% (DEFRA, 2001).
Conjugated Linoleic Acid (CLA) is a mixture of isomers of linoleic acid implicated with numerous health promoting properties. These include anti-carcinogenicity (cis -9, trans -11 isomer), anti-atherogenicity and increasing the lean:fat ratio (trans -10, cis -12 isomer). CLA is produced naturally by all ruminant animals through the incomplete biohydrogenation of linoleic acid within the rumen. Alternatively, it can be made endogenously by stearoyl coenzyme A desaturase (SCD) from vaccenic acid (VA) (Griinari et al, 2000). It has been well documented that cows fed on a grass diet produce more cis -9, trans -11 in milk than those fed on a concentrate based regime (Kelly et al, 1998) but to date, little work would appear to have been undertaken to determine if this is the case with sheep tissues. In the present study, a grass based diet was compared with a concentrate diet in order to determine whether the CLA content of adipose tissue differed and if so, which isomer and what mechanisms may be involved.
Recent research has focused on a component of ruminant fat, conjugated linoleic acids (CLA), which have been implicated with numerous health promoting properties including anti-carcinogenicity (Belury, 1995). Dietary supplementation with CLA has been shown to have a marked effect on tissue composition in several species, although there is apparently no evidence of such effects being seen in sheep (see Salter et al., 2002). Consequently, the aim of this study was to examine the effect of feeding growing lambs a CLA supplement, protected from rumen degradation, on carcass characteristics and tissue CLA content.
Compared to meat from other animals lamb contains high levels of saturated fat, particularly stearic acid which comprises 18% of the total fatty acids (Enser et al, 1996). This stearic acid can be desaturated in the tissue by stearoyl coenzyme A desaturase (SCD) to produce oleic acid. In sheep SCD is produced from a single gene and the levels of SCD mRNA in the tissue correlate well with oleic acid (Ward et al, 1998, Barber et al, 2000) suggesting that an upregulation of SCD activity may increase the relative proportions of unsaturated and saturated fatty acids and so significantly improve the nutritional quality of sheep meat. Our recent studies have shown that insulin increases SCD mRNA levels and monounsaturated fatty acid synthesis in cultured ovine adipose tissue explants (Daniel et al, 2001). The present study was designed to investigate whether feeding a diet believed to manipulate SCD mRNA concentrations would significantly alter the fatty acid composition of lamb.
The final stages of low-mass stellar evolution are characterized by significant mass loss due to stellar pulsations during the AGB phase, which lead to the development of planetary nebulae. Molecular masers of H2O, SiO, and ground state OH transitions are commonly detected in oxygen-rich late-type stars (OH/IR objects). In contrast, excited OH maser transitions are rare. We discuss our study of the carbon-rich pre-planetary nebula CRL618 (a prototypical post-AGB star). Observations conducted in May 2008 with the 305m Arecibo Telescope resulted in the first detection of a 4765MHz OH maser line in a late-type stellar object; the detection was confirmed a few months later also with Arecibo. Subsequent observations in 2015 and 2017 resulted in non-detection of the 4765MHz OH line. Our observations indicate that the 4765MHz OH maser in CRL 618 is highly variable, possibly tracing a short-lived phenomenon during the development of a pre-planetary nebula.
As the first part of a program to investigate the thermal emission of dust at millimeter wavelengths, we present maps of the continuum emission from radio-bright HII regions. These maps have been made with a filled aperture telescope, the NRAO 12-m telescope at Kitt Peak, with a HPBW of 70 arc seconds at 3.5 mm. We used a switched dual-beam technique and a restoration algorithm developed by Emerson et al. (1979 Astron. Ap. 76, 92). We compare these maps with maps made at centimeter wavelengths.