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 email@example.com
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 study was undertaken to investigate the antiparasitic activity of extracellular products of Streptomyces albus. Bioactivity-guided isolation of chloroform extracts affording a compound showing potent activity. The structure of the compound was elucidated as salinomycin (SAL) by EI-MS, 1H NMR and 13C NMR. In vitro test showed that SAL has potent anti-parasitic efficacy against theronts of Ichthyophthirius multifiliis with 10 min, 1, 2, 3 and 4 h (effective concentration) EC50 (95% confidence intervals) of 2.12 (2.22–2.02), 1.93 (1.98–1.88), 1.42 (1.47–1.37), 1.35 (1.41–1.31) and 1.11 (1.21–1.01) mg L−1. In vitro antiparasitic assays revealed that SAL could be 100% effective against I. multifiliis encysted tomonts at a concentration of 8.0 mg L−1. In vivo test demonstrated that the number of I. multifiliis trophonts on Erythroculter ilishaeformis treated with SAL was markedly lower than that of control group at 10 days after exposed to theronts (P < 0.05). In the control group, 80% mortality was observed owing to heavy I. multifiliis infection at 10 days. On the other hand, only 30.0% mortality was recorded in the group treated with 8.0 mg L−1 SAL. The median lethal dose (LD50) of SAL for E. ilishaeformis was 32.9 mg L−1.
Whether there are distinct subtypes of schizophrenia is an important issue to advance understanding and treatment of schizophrenia.
To understand and treat individuals with schizophrenia, the aim was to advance understanding of differences between individuals, whether there are discrete subtypes, and how fist-episode patients (FEP) may differ from multiple episode patients (MEP).
These issues were analysed in 687 FEP and 1880 MEP with schizophrenia using the Positive and Negative Syndrome Scale for (PANSS) schizophrenia before and after antipsychotic medication for 6 weeks.
The seven Negative Symptoms were correlated with each other and with P2 (conceptual disorganisation), G13 (disturbance of volition), and G7 (motor retardation). The main difference between individuals was in the cluster of seven negative symptoms, which had a continuous unimodal distribution. Medication decreased the PANSS scores for all the symptoms, which were similar in the FEP and MEP groups.
The negative symptoms are a major source of individual differences, and there are potential implications for treatment.
The sea cucumber Apostichopus japonicus is a deposit-feeder and vital for marine benthic ecosystems. Hypoxia can influence the behaviour and even lead to massive mortality in A. japonicus in the wild. It is important to understand the molecular responses of A. japonicus when exposed to acute changes in dissolved oxygen (DO) concentration. In this study, RNA-seq provided a general overview of the gene expression profiles of the respiratory tree of A. japonicus exposed to DO of 8 mg l−1 (DO8), 4 mg l−1 (DO4) and 2 mg l−1 (DO2) conditions. Differentially expressed genes (DEGs) screening with the NOISeq method identified 51, 59 and 61 DEGs according to the criteria of fold change ≥2 and divergence probability ≥0.8 in the comparisons of DO2 vs DO4, DO2 vs DO8 and DO4 vs DO8, respectively. Gene ontology analysis showed that ‘cellular process’ and ‘binding’ had the most enriched DEGs in the categories of ‘biological process’ and ‘molecular function’, respectively (catalytic activity also had the most enriched DEGs in the category of ‘molecular function’ based on the comparison of DO2 vs DO8), while ‘cell’ and ‘cell part’ had the most enriched DEGs in the category of ‘cellular component’. The DEGs were mapped to 79, 81 and 104 pathways in the KEGG database, and 8, 29 and 16 pathways were significantly enriched, respectively. The DO-specific DEGs identified in this study of the respiratory tree are important targets for further research into the biochemical mechanisms involved in the response of the sea cucumber to changes in the DO concentration.
The present study aimed to investigate the effect of maternal malnutrition on offspring glucose tolerance and the epigenetic mechanisms involved. In total, twelve primiparous Landrace×Yorkshire gilts were fed rations providing either 100 % (control (CON)) or 75 % (undernutrition (UN)) nutritional requirements according to the National Research Council recommendations, throughout gestation. Muscle samples of offspring were collected at birth (dpn1), weaning (dpn28) and adulthood (dpn189). Compared with CON pigs, UN pigs showed lower serum glucose concentrations at birth, but showed higher serum glucose and insulin concentrations as well as increased area under the blood glucose curve during intravenous glucose tolerance test at dpn189 (P<0·05). Compared with CON pigs, GLUT-4 gene and protein expressions were decreased at dpn1 and dpn189 in the muscle of UN pigs, which was accompanied by increased methylation at the GLUT4 promoter (P<0·05). These alterations in methylation concurred with increased mRNA levels of DNA methyltransferase (DNMT) 1 at dpn1 and dpn28, DNMT3a at dpn189 and DNMT3b at dpn1 in UN pigs compared with CON pigs (P<0·05). Interestingly, although the average methylation levels at the muscle GLUT4 promoter were decreased at dpn189 compared with dpn1 in pigs exposed to a poor maternal diet (P<0·05), the methylation differences in individual CpG sites were more pronounced with age. Our results indicate that in utero undernutrition persists to silence muscle GLUT4 likely through DNA methylation during the ageing process, which may lead to the amplification of age-associated glucose intolerance.
Pin/pin “micromorph” tandem solar cells were manufactured by the industrial production line of Hunan Gongchuang PV Science & Technology Co., Ltd. Based on this kind of solar cells, a n-doped amorphous silicon layer deposited by plasma enhanced chemical vapor deposition technique (PECVD) was inserted between the microcrystalline silicon intrinsic layer and n-doped layer. The result showed that the introduced n-type amorphous silicon layer well improved the solar cells performance by reducing the bad effects caused by microcrystalline silicon growth defects. Compared with the solar cells without inserting the n-doped amorphous silicon layer, the open voltage and efficiency increased remarkably. When the thickness of n-doped amorphous silicon layer is 8nm, the open voltage increased from 72.9V to 73.6V and efficiency increased from 10.63% to 10.74%.
For the industrial application of silicon thin film solar cells, the current focus is on how to realize high-efficiency low-cost production process and minimize light-induced degradation effect, thus effectively reducing the balance-of-system (BOS) costs of system integration. In this paper, a brief introduction based on our development and application in this area is presented, highlighting in the achievement of some layers in a-Si:H/μc-Si:H tandem solar cell by optimizing the property of single layers, such as amorphous intrinsic layer, intermediate reflective layer and microcrystalline intrinsic layer. After transferring the process achievement to the industrial production line, we obtained the low-cost thin-film silicon solar cells with high photovoltaic conversion efficiency of 10.2%.
While demand response has achieved promising results on making the power grid more efficient and reliable, the additional dynamics and flexibility brought by demand response also increase the uncertainty and complexity of the centralized load forecast. In this paper, we propose a game-theoretic demand response scheme that can transform the traditional centralized load prediction structure into a distributed load prediction system by the participation of customers. Moreover, since customers are generally rational and thus naturally selfish, they may cheat if cheating can improve their payoff. Therefore, enforcing truth-telling is crucial. We prove analytically and demonstrate with simulations that the proposed game-theoretic scheme is incentive compatible, i.e., all customers are motivated to report and consume their true optimal demands and any deviation will lead to a utility loss. We also prove theoretically that the proposed demand response scheme can lead to the solution that maximizes social welfare and is proportionally fair in terms of utility function. Moreover, we propose a simple dynamic pricing algorithm for the power substation to control the total demand of all customers to meet the target demand curve. Finally, simulations are shown to demonstrate the efficiency and effectiveness of the proposed game-theoretic algorithm.
Our aim is to screen miRNAs and genes related to tetralogy of Fallot and construct a co-expression network based on integrating miRNA and gene microarrays. We downloaded the gene expression profile GSE35490 (miRNA) and GSE35776 (mRNA) of tetralogy of Fallot from the Gene Expression Omnibus database, which includes eight normal and 15 disease samples from infants, and screened differentially expressed miRNAs and genes between normal and disease samples (cut-off: p < 0.05; FDR < 0.05; and log FC > 2 or log FC < −2); in addition, we downloaded human miRNA and their targets, which were collected in the miRNA targets prediction database TargetScan, and selected ones that also appeared in our differentially expressed miRNAs and their predicted targets (score >0.9) and then made a relationship of diff_miRNAs and diff_genes of our results. Finally, we uploaded all the diff_target genes into String, constructed a co-expression network regulated by diff_miRNAs, and performed functional analysis with the software DAVID. Comparing normal and disease lesion tissue, we got 32 and 875 differentially expressed miRNAs and genes, respectively, and found hsa-miR-124 with 34 diff_target genes and hsa-miR-138 with two diff_target genes. Then we constructed a co-expression network that contains 231 pairs of genes. Genes in the network were enriched into 14 function clusters, and the most significant one is protein localisation. We screened the tetralogy of Fallot-related hsa-miR-124 and hsa-miR-138 with their direct and indirect differentially expressed target genes, and found that protein localisation is the significant cause affecting tetralogy of Fallot. Our approach may provide the groundwork for a new therapy approach to treating tetralogy of Fallot.
Low-density lipoproteins (LDL) is known to protect boar sperm during freezing–thawing, but little information is known about the effects of LDL extracted from different avian egg yolks on post-thaw boar semen quality. The purpose of this study was to compare and analyze the effects of LDL at various concentrations and different species on boar sperm quality after freezing–thawing. LDL extracted from the yolk of hen egg, duck egg, quail egg, pigeon egg or ostrich egg was added to the extender at the concentrations of 0.06, 0.07, 0.08, 0.09 and 0.1 g/ml, respectively, and their effects on frozen–thawed boar sperm quality were assessed. According to all measured parameters, the results showed that sperm motility, acrosome integrity and plasma membrane integrity were 43.20%, 52.57% and 48.13%, respectively, after being frozen–thawed with 0.09 g/ml LDL extracted from pigeon egg yolk. All these quality parameters were higher than that of other groups (P < 0.05). In conclusion, our results confirmed that LDL extracted from pigeon egg yolk had the best cryoprotective effects on frozen–thawed boar sperm among all of the groups supplemented with LDL from five kinds of avian egg in extender. The optimum concentration of LDL extracted from pigeon egg in boar semen freezing extender was 0.09 g/ml.
In 2008 January the 24th Chinese expedition team successfully deployed the Chinese Small Telescope ARray (CSTAR) to Dome A, the highest point on the Antarctic plateau. CSTAR consists of four 14.5cm optical telescopes, each with a different filter (g, r, i and open) and has a 4.5°×4.5° field of view (FOV). Based on the CSTAR data, initial statistics of astronomical observational site quality and light curves of variable objects were obtained. To reach higher photometric quality, we are continuing to work to overcome the effects of uneven cirrus cloud cirrus, optical “ghosts” and intra-pixel sensitivity. The snow surface stability is also tested for further astronomical observational instrument and for glaciology studies.
Protein tyrosine phosphatase 1B (PTP1B) is implicated in the negative regulation of the insulin signalling pathway by dephosphorylating the insulin receptor (IR) and IR substrates. Ganodermalucidum has traditionally been used for the treatment of diabetes in Chinese medicine; however, its anti-diabetic potency and mechanism in vivo is still unclear. Our previously published study reported a novel proteoglycan PTP1B inhibitor, named Fudan-Yueyang-Ganoderma lucidum (FYGL) from G. lucidum, with a half-maximal inhibitory concentration (IC50) value of 5·12 (sem 0·05) μg/ml, a protein:polyglycan ratio of 17:77 and 78 % glucose in polysaccharide, and dominant amino acid residues of aspartic acid, glycine, glutamic acid, alanine, serine and threonine in protein. FYGL is capable of decreasing plasma glucose in streptozotocin-induced diabetic mice with a high safety of median lethal dose (LD50) of 6 g/kg. In the present study, C57BL/6 db/db diabetic mice were trialed further using FYGL as well as metformin for comparison. Oral treatment with FYGL in db/db diabetic mice for 4 weeks significantly (P < 0·01 or 0·05) decreased the fasting plasma glucose level, serum insulin concentration and the homeostasis model assessment of insulin resistance. FYGL also controlled the biochemistry indices relative to type 2 diabetes-accompanied lipidaemic disorders. Pharmacology research suggests that FYGL decreases the plasma glucose level by the mechanism of inhibiting PTP1B expression and activity, consequently, regulating the tyrosine phosphorylation level of the IR β-subunit and the level of hepatic glycogen, thus resulting in the improvement of insulin sensitivity. Therefore, FYGL is promising as an insulin sensitiser for the therapy of type 2 diabetes and accompanied dyslipidaemia.
The coast of Bohai Bay, north-western Yellow Sea, is critical for waterbirds migrating along the East Asia-Australasian Flyway. Between 1994 and 2010, a total of 450 km2 of offshore area, including 218 km2 of intertidal flats (one third of the original tidal area in the bay), has been reclaimed along the bay for two industrial projects. This has caused the northward migrants to become concentrated in an ever smaller remaining area, our core study site. The spring peak numbers of two Red Knot subspecies in the East Asia-Australasian Flyway, Calidris canutus piersmai and C. c. rogersi, in this so far little affected area increased from 13% in 2007 to 62% in 2010 of the global populations; the spring peak numbers of Curlew Sandpiper C. ferruginea increased from 3% in 2007 to 23% in 2010 of the flyway population. The decline in the extent of intertidal mudflats also affected Relict Gulls Larus relictus, listed by IUCN as ‘Vulnerable’; during normal winters 56% of the global population moved from the wintering habitats that were removed in Tianjin to the relatively intact areas around Tangshan. Densities of wintering Eurasian Curlew Numenius arquata, and spring-staging Broad-billed Sandpiper Limicola falcinellus and Sanderling Calidris alba have also increased in the remaining areas. With the proposed continuation of land reclamation in Bohai Bay, we predict waterbird densities in the remaining areas to increase to a point of collapse. To evaluate the future of these fragile, shared international resources, it is vital to promote an immediate conservation action plan for the remaining coastal wetlands in this region, and continued population monitoring to determine the effects of this action.
We have used small-angle x-ray scattering (SAXS) in conjunction with X-ray diffraction (XRD) to study the nanostructure of hydrogenated nanocrystalline silicon (nc-Si:H). The crystallite size in the growth direction, as deduced from XRD data, is 24 nm with a preferred  orientation in the growth direction of the film. Fitting the SAXS intensity shows that the scattering derives from electron density fluctuations of both voids in the amorphous phase and H-rich clusters in the film, probably at the crystallite interfaces. The SAXS results indicate ellipsoidal shaped crystallites about 6 nm in size perpendicular to the growth direction. We annealed the samples, stepwise, and then measured the SAXS and ESR. At temperatures below 350◦C, we observe an overall increase in the size of the scattering centers on annealing but only a small change in the spin density, which suggests that bond reconstruction on the crystallite surfaces takes place with high efficacy.
Background: Several studies have investigated the association of FKBP5 gene polymorphisms with mood disorders, but findings are not always consistent. The aim of our study was to assess the association of FKBP5 gene polymorphisms with mood disorders using a meta-analysis.
Methods: Data were collected from the following electronic databases: PubMed, Elsevier Science Direct, Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure and Wanfang, with the last report up to March 2010. Meta-analysis was performed in a fixed/random effect model.
Results: We identified six studies using search, and one study was excluded because of unavailable data. One study contained data on two different ethnicities and we treated them independently. Thus, six separate studies (2655 cases and 3593 controls) were included in the meta-analysis. Meta-analysis was performed for three FKBP5 gene polymorphisms (rs1360780, rs3800373 and rs4713916) in overall and Caucasian populations. We did not detect any association of FKBP5 gene rs1360780 and rs3800373 polymorphisms with mood disorders (p > 0.05). However, a significant association of FKBP5 gene rs4713916 polymorphism with mood disorders was found, and the heterozygous individual (GA genotype) was more susceptible to mood disorders in comparison to homozygous analogues (GG or AA genotype) [overall: GA vs. GG: OR (odds ratio) = 1.20, 95% CI (confidence interval) = 1.03–1.40, p = 0.02; GA vs. AA: OR = 1.44, 95% CI = 1.09–1.90, p = 0.009; Caucasian: GA vs. GG: OR = 1.22, 95% CI = 1.04–1.44, p = 0.01; GA vs. AA: OR = 1.43, 95% CI = 1.09–1.89, p = 0.01].
Conclusion: This meta-analysis shows that mood disorders are associated with FKBP5 gene rs4713916 polymorphism, but not with rs1360780 and rs3800373.
PLATO is a fully-robotic observatory designed for operation in
Antarctica. It generates its own electricity (about 1 kW), heat
(sufficient to keep two 10-foot shipping containers comfortably above
0°C when the outside temperature is at -70°C), and
connects to the internet using the Iridium satellite system (providing
~30 MB/day of data transfer). Following a successful first year of
operation at Dome A during 2008, PLATO was upgraded with
new instruments for 2009.
The THz spectral region includes a number of important transitions which
allow us to trace the evolution of the interstellar medium. Because of the
opacity of the atmosphere in this spectral range, the best sites for
ground-based THz observations are on the Antarctic Plateau; of these sites,
Dome A is expected to be the best. THz survey science can be carried out
with small telescopes, easing logistical constraints. By deploying a
submillimetre-wave tipper/ telescope to Dome A, we have trialled several
technologies for such an instrument, and we are able to test whether the
site quality is sufficient for THz surveys.
In January 2005, members of a Chinese expedition team were the first
humans to visit Dome A on the Antarctic plateau, a site
predicted to be one of the very best astronomical sites on earth. In 2006, the Chinese Center for Antarctic Astronomy (CCAA) was founded
to promote the development of astronomy in Antarctica, especially at
Dome A. CCAA has since taken part in two traverses to Dome A, organized
by the Polar Research Institute of China (PRIC), in the austral
summers of 2007/2008 and 2008/2009. These traverses resulted in the
installation of many site-testing and science instruments, supported
by the PLATO observatory. The Chinese Small Telescope ARray (CSTAR)
has produced excellent results from Dome A. Our future plans include further site-testing work, and the following
full-scale science instruments: three 0.5-m Antarctic Schmidt
Telescopes (AST3), and a proposed 4-m telescope for wide-field
infrared high spatial-resolution surveys. The first AST3 telescope is
under construction and is scheduled for installation in 2011.
The genetic diversities of 72 individuals from three wild Lenok populations of Mudanjiang River (MD), Yalujiang River (YL) and Wusulijiang River (WSL) in the northeast of China were analysed using amplified fragment length polymorphism (AFLP) markers. The results showed that 541 polymorphic loci out of 559 were amplified by 12 primer pairs and the percentage of polymorphic loci was 96.78%. Shannon indices for the MD, YL and WSL populations were 0.3988±0.2913, 0.3254±0.3037, 0.2125±0.2862, respectively, and Nei's gene diversity indices were 0.2737±0.2062, 0.2229±0.2129, 0.1446±0.1985, respectively. The average total genetic diversity (Ht) was 0.3512±0.0.0208 and the average genetic diversity within populations (Hs) was 0.2137±0.0152. Among the three populations, the average genetic distance (Dst) was 0.1375 and the gene differentiation coefficient (Gst) was 0.3914. The genetic diversity was 60.85% within populations and 39.15% among populations. The gene flow index (Nm) was 0.7776. The analysis of molecular variance (AMOVA) indicated that the average fixation index (Fst) was 0.55336. The variance was 55.16% within populations and 44.84% among populations. The highest polymorphism ratio was in the MD group and the lowest in the WSL group.
PLATO is a 6 tonne completely self-contained robotic observatory that provides its own heat, electricity, and satellite communications. It was deployed to Dome A in Antarctica in January 2008 by the Chinese expedition team, and is now in its second year of operation. PLATO is operating four 14.5cm optical telescopes with 1k × 1k CCDs, a wide-field sky camera with a 2k × 2k CCD and Sloan g, r, i filters, a fibre-fed spectrograph to measure the UV to near-IR sky spectrum, a 0.2m terahertz telescope, two sonic radars giving 1m resolution data on the boundary layer to a height of 180m, a 15m tower, meteorological sensors, and 8 web cameras. Beginning in 2010/11 PLATO will be upgraded to support a Multi Aperture Scintillation Sensor and three AST3 0.5m schmidt telescopes, with 10k × 10 CCDs and 100TB/annum data requirements.
Background: Increasing evidence suggests that neprilysin (NEP) may be the major degrading enzyme of amyloid beta (Aβ) in the brain and the NEP gene has been proposed as a candidate gene for Alzheimer's disease (AD). Association results between the NEP gene and AD are still preliminary. This study investigates the effect of the polymorphisms of −204G/C and 159C/T in the NEP gene on the development of sporadic Alzheimer's disease (SAD) in a southern Chinese community.
Method: 236 sporadic late-onset AD patients were recruited from Guangzhou Psychiatric Hospital in southern China, and 332 healthy elderly controls were enrolled from three old age homes in suburban Guangzhou. NEP and ApoE genotype were determined by PCR–RFLP.
Results: No differences in genotypic and allelic frequencies of −204G/C and 159C/T polymorphisms in NEP were found between AD and control group (for −204G/C genotype: χ2 = 2.34, P > 0.05; for allele: χ2 = 2.31, P > 0.05; for 159C/T genotype: χ2 = 1.34, P > 0.05; for allele: χ2 = 0.88, P > 0.05). Neither was any difference found in genotypic and allelic frequency when stratified by sex or by ApoE ε4 allele (P > 0.05).
Conclusions: Our results suggest that −204G/C and 159C/T polymorphisms of the NEP gene may not be associated with SAD. Moreover, both sex and ApoE ε4 allele do not affect the distribution of NEP gene polymorphisms.