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The objective of present study was to investigate the effect of curcumin on insulin resistance and hepatic lipid accumulation in intrauterine growth restriction (IUGR). Rats with a normal birth weight (NBW) or IUGR were fed basic diets (NBW and IUGR groups) or basic diets supplemented with curcumin (NBW-C and IUGR-C groups) from 6 to 12 weeks. Rats with IUGR showed higher levels of glucose and homeostasis model assessment index (HOMA-IR) (P<0.05) than in NBW group. The livers of IUGR rats exhibited higher (P<0.05) concentration of triglyceride and lower (P<0.05) activities of lipolysis enzymes compared with the normal rats. In response to dietary curcumin supplementation, concentrations of serum insulin, glucose and HOMA-IR, pyruvate, triglyceride, total cholesterol and non-esterified fatty acid in the liver were decreased (P<0.05). The concentrations of glycogen and activities of lipolysis enzymes in the liver were increased (P<0.05) in the IUGR-C group than in the IUGR group. These results were associated with lower (P<0.05) phosphorylated insulin receptor substrate 1 (IRS-1), Akt, glycogen synthase kinase 3β (GSK3β) and expressions of sterol regulatory element binding proteins 1 (SREBP1) and fatty acid synthase (FASN); decreased expressions for Cd36, Srebf1 and Fasn; increased (P<0.05) expression of peroxisome proliferator-activated receptor α (PPARα) and expressions for Ppara and hormone sensitive lipase (HSL) in the liver of IUGR-C rats than the IUGR rats. Maternal malnutrition caused insulin resistance and lipid accumulation in the liver. Curcumin supplementation prevented insulin resistance by regulating insulin signaling pathways and attenuated hepatic lipid accumulation.
Maternal effects on offspring seeds are mainly caused by seed position on, and the abiotic environment of, the mother plant. Seed heteromorphism, a special form of position effect, is the production by an individual plant of morphologically distinct seed types, usually with different ecological behaviours. Seed heteromorphism is assumed to be a form of bet hedging and provides an ideal biological model to test theoretical predictions. Most studies of maternal effects on seeds have focused on abiotic environmental factors and changes in mean seed traits of offspring. Suaeda salsa is an annual halophyte that produces dimorphic seeds within the same inflorescence. We tested the hypothesis that plants grown from brown seeds of S. salsa have a higher offspring brown seed:black seed morph ratio and variance in seed size than plants from black seeds. Results from a pot experiment showed that plants grown from brown seeds had a higher brown seed:black seed ratio than plants grown from black seeds. This is the first layer of dynamic bet hedging. Brown seeds had higher size variation than black seeds, and seeds produced by plants from brown seeds also had higher seed size variation than plants grown from black seeds. This is the second layer of dynamic bet hedging. Thus, the maternal effect of seed heteromorphism is dual dynamic bet hedging. Furthermore, for seed traits we verified for the first time the theoretical prediction that an increase in offspring size variability induces an increase in the mean size of offspring.
The Katian (Upper Ordovician) Shiyanhe Formation at the Sigang section, Neixiang area, Henan Province, central China, has been investigated for carbon isotope (δ13Ccarb) chemostratigraphy. The carbon isotopic data document signal between the two major Ordovician positive shifts in δ13C, the early Katian Guttenberg and the Hirnantian excursions. The Kope (Ka1/2), Fairview (Ka2/3), Waynesville (Ka3/4), Whitewater (Ka4) excursions and a doubtful Elkhorn (Ka4) excursion are identified herein. The continuous and well-defined conodont zonal succession of the Sigang section provides a secure biostratigraphic framework for the mid-late Katian carbon isotope chemostratigraphy in China. Correlation between carbon-isotope data curve and the relative sea-level changes shows no clear correspondence, and hence the sea-level change is probably not the main driver of δ13C excursions during the Katian. Intercontinentally, the mid–late Katian carbon isotope excursions, identified mainly in the North American and Baltoscandian successions, are useful for improving long-distance stratigraphic correlations. This further suggests that these excursions represent global perturbations in the carbon cycle.
Maternal one-carbon metabolism during pregnancy is crucial for fetal development and programming by DNA methylation. However, evidence on one-carbon biomarkers other than folate is lacking. We, therefore, investigated whether maternal plasma methyl donors, that is, choline, betaine and methionine, are associated with birth outcomes. Blood samples were obtained from 115 women during gestation (median 26·3 weeks, 90 % range 22·7–33·0 weeks). Plasma choline, betaine, methionine and dimethylglycine were measured using HPLC-tandem MS. Multivariate linear and logistic regression models were used to estimate the association between plasma biomarkers and birth weight, birth length, the risk of small-for-gestational-age and large-for-gestational-age (LGA). Higher level of maternal betaine was associated with lower birth weight (–130·3 (95 % CI –244·8, –15·9) per 1 sd increment for log-transformed betaine). Higher maternal methionine was associated with lower risk of LGA, and adjusted OR, with 95 % CI for 1 sd increase in methionine concentration was 0·44 (95 % CI 0·21, 0·89). Stratified analyses according to infant sex or maternal plasma homocysteine status showed that reduction in birth weight in relation to maternal betaine was only limited to male infants or to who had higher maternal homocysteine status (≥5·1 µmol/l). Higher maternal betaine status was associated with reduced birth weight. Maternal methionine was inversely associated with LGA risk. These findings are needed to be replicated in future larger studies.
Global Navigation Satellite System (GNSS) observations contain various errors, the separation and measurement of which is a popular research topic. Multipath effect on code measurements is investigated through the multipath combination, but carrier multipath error is small, and it is difficult to distinguish from other errors, such as hardware delay, carrier noise and satellite inherent biases. However, as the number of frequency points increases during the rapid development of GNSSs, it is possible to analyse the abovementioned errors in detail. Triple-frequency combination can be used to eliminate the first order ionospheric error, and a quad-frequency combination has one degree of freedom, which may be used to minimise carrier error effects. For this reason, an optimum method has been developed for multi-frequency GNSS code-multipath combination measurements, which has been verified by exploiting BeiDou System (BDS), three frequency data from an International GNSS Service (IGS) station and a city canyon as well as actual sampled quad-frequency data. By comparative analysis, we found that the fluctuations of an optimum triple-frequency combination are smaller than that of the non-optimum combination, which decreases the influence of inherent errors and biases on carrier phase. At the same time, second-order ionospheric error can be effectively eliminated as well. This provides a new code-multipath combination measurement optimisation methodology for future multi-frequency BDS and other GNSSs.
Although numerous studies have used functional neuroimaging to identify executive dysfunction in patients with bipolar disorder (BD), the findings are not consistent. The aim of this meta-analysis is to identify the most reliable functional anomalies in BD patients during performance of Executive Function (EF) tasks.
A web-based search was performed on publication databases to identify functional magnetic resonance imaging studies of BD patients performing EF tasks and a voxel-based meta-analytic method known as anisotropic Effect Size Signed Differential Mapping (ES-SDM) was used to identify brain regions which showed anomalous activity in BD patients compared with healthy controls (HC).
Twenty datasets consisting of 463 BD patients and 484 HC were included. Compared with HC, BD patients showed significant hypo-activation or failure of activation in the left striatum (p = 0.00007), supplementary motor area (BA 6, p = 0.00037), precentral gyrus (BA 6, p = 0.0014) and cerebellum (BA 37, p = 0.0019), and hyper-activation in the left gyrus rectus (BA 11, p ≈ 0) and right middle temporal gyrus (BA 22, p = 0.00031) during performance of EF tasks. Sensitivity and subgroup analyses showed that the anomaly of left striatum is consistent across studies and present in both euthymic and BD I patients.
Patients with BD consistently showed abnormal activation in the cortico-striatal system during performance of EF tasks compared with HC. Failure of activation of the striatum may be a reliable marker for impairment in performance of especially inhibition tasks by patients with BD.
Porphyrins are a class of conjugated molecules that structurally and functionally resemble natural photosynthetic and enzymatic chromophores. Crystalline solids self-assembled from anionic and cationic porphyrins yield a new class of multifunctional optoelectronic micro- and nanomaterials. In this article, we provide details on the concept of binary ionic self-assembly (ISA) and ionized forms of porphyrins, as well as formation of hierarchical structures, including nanotubes, rods and ribbons, sheets, and three-dimensional clover-like shapes, spheres, and sheaf-like structures. We summarize key physical properties from ultraviolet–visible characterizations of J-aggregate, exciton delocalization and extended π–π stacking, and related electronic and light-harvesting properties of the structures. Depending on the molecular subunits, the functionalities of the ISA materials are altered. These ISA nanostructures possess attractive light-harvesting and charge- and energy-transport functionalities and allow access to a novel class of nanomaterials with potential for applications in sensors, photovoltaics, photocatalysis, and solar power.
We prove that positive solutions of an integral equation of Wolff type are radially symmetric and decreasing about some point in
. The hypotheses allow a wider range of exponents and are easier to apply than those in previous work.
Major depressive disorder (MDD) is a leading cause of disability worldwide and influenced by both environmental and genetic factors. Genetic studies of MDD have focused on common variants and have been constrained by the heterogeneity of clinical symptoms.
We sequenced the exome of 77 cases and 245 controls of Han Chinese ancestry and scanned their brain. Burden tests of rare variants were performed first to explore the association between genes/pathways and MDD. Secondly, parallel Independent Component Analysis was conducted to investigate genetic underpinnings of gray matter volume (GMV) changes of MDD.
Two genes (CSMD1, p = 5.32×10−6; CNTNAP5, p = 1.32×10−6) and one pathway (Neuroactive Ligand Receptor Interactive, p = 1.29×10−5) achieved significance in burden test. In addition, we identified one pair of imaging-genetic components of significant correlation (r = 0.38, p = 9.92×10−6). The imaging component reflected decreased GMV in cases and correlated with intelligence quotient (IQ). IQ mediated the effects of GMV on MDD. The genetic component enriched in two gene sets, namely Singling by G-protein coupled receptors [false discovery rate (FDR) q = 3.23×10−4) and Alzheimer Disease Up (FDR q = 6.12×10−4).
Both rare variants analysis and imaging–genetic analysis found evidence corresponding with the neuroinflammation and synaptic plasticity hypotheses of MDD. The mediation of IQ indicates that genetic component may act on MDD through GMV alteration and cognitive impairment.
Seasonal autoregressive-integrated moving average (SARIMA) has been widely used to model and forecast incidence of infectious diseases in time-series analysis. This study aimed to model and forecast monthly cases of hand, foot and mouth disease (HFMD) in China. Monthly incidence HFMD cases in China from May 2008 to August 2018 were analysed with the SARIMA model. A seasonal variation of HFMD incidence was found from May 2008 to August 2018 in China, with a predominant peak from April to July and a trough from January to March. In addition, the annual peak occurred periodically with a large annual peak followed by a relatively small annual peak. A SARIMA model of SARIMA (1, 1, 2) (0, 1, 1)12 was identified, and the mean error rate and determination coefficient were 16.86% and 94.27%, respectively. There was an annual periodicity and seasonal variation of HFMD incidence in China, which could be predicted well by a SARIMA (1, 1, 2) (0, 1, 1)12 model.
In this paper, we reported both the experimental demonstration and theoretical analysis of a Raman fiber laser based on a master oscillator–power amplifier configuration. The Raman fiber laser adopted the dual-wavelength bidirectional pumping configuration, utilizing 976 nm laser diodes and 1018 nm fiber lasers as the pump sources. A 60-m-long
ytterbium-doped fiber was used to convert the power from 1070 to 1124 nm, realizing a maximum power output of 3.7 kW with a 3 dB spectral width of 6.8 nm. Moreover, we developed a multi-frequency model taking into consideration the Raman gain spectrum and amplified spontaneous emission. The calculated spectral broadening of both the forward and backward laser was in good agreement with the experimental results. Finally, a 1.5 kW, 1183 nm second-order Raman fiber laser was further experimentally demonstrated by the addition of a 70-m-long germanium-doped passive fiber.
Energy chirp compensation of the electron bunch (e-bunch) in a laser wakefield accelerator, which is caused by the phase space rotation in the gradient wakefield, has been applied in many schemes for low energy spread e-bunch generation. We report the experimental observation of energy chirp compensation of the e-bunch in a nonlinear laser wakefield accelerator with a negligible beam loading effect. By adjusting the acceleration length using a wedge-roof block, the chirp compensation of the accelerated e-bunch was observed via an electron spectrometer. Apart from this, some significant parameters for the compensation process, such as the longitudinal dispersion and wakefield slope at the bunch position, were also estimated. A detailed comparison between experiment and simulation shows good agreement of the wakefield and bunch parameters. These results give a clear demonstration of the longitudinal characteristics of the wakefield in a plasma and the bunch dynamics, which are important for better control of a compact laser wakefield accelerator.
In this paper, we study the existence, nonexistence and mass concentration of L2-normalized solutions for nonlinear fractional Schrödinger equations. Comparingwith the Schrödinger equation, we encounter some new challenges due to the nonlocal nature of the fractional Laplacian. We first prove that the optimal embedding constant for the fractional Gagliardo–Nirenberg–Sobolev inequality can be expressed by exact form, which improves the results of [17, 18]. By doing this, we then establish the existence and nonexistence of L2-normalized solutions for this equation. Finally, under a certain type of trapping potentials, by using some delicate energy estimates we present a detailed analysis of the concentration behavior of L2-normalized solutions in the mass critical case.
Conotruncal heart defects are considered to be one of the most common types of birth defect worldwide. Genetic disturbances in folate metabolism such as Thymidylate synthase may increase risk for conotruncal heart defects. We evaluated two common Thymidylate synthase polymorphisms, including the 28 bp tandem repeat in the promoter enhancer region of the 5′-untranslated region and the 6 bp deletion in the 3′-untranslated region, as risk factors of conotruncal heart defects including various subtypes of malformations, in a total of 193 mothers with conotruncal heart defect in offspring and 234 healthy controls in the Chinese population. Logistic regression analyses revealed that mothers who were homozygotes with deletion (−/−) had a 1.8-fold (odds ratio: 1.8; 95% confidence interval: 1.0–3.0, p = 0.040) increased risk for conotruncal heart defect in offspring, respectively, when compared with mothers carrying the wild type (+/+) genotype. Consistently, individuals carrying the genotype −/− of the Thymidylate synthase 6 bp deletion also had higher plasma homocysteine levels compared to the mothers carrying the genotype +/+ in the control and conotruncal heart defect groups (p = 0.006 and p = 0.004, respectively). However, our results showed that Thymidylate synthase 28 bp tandem repeat polymorphism was not associated with risk for conotruncal heart defect and plasma homocysteine level. In conclusion, our data suggest that the maternal Thymidylate synthase 6 bp deletion polymorphism might be associated with plasma homocysteine level and risk for conotruncal heart defect in offspring.
Muons produced by the Bethe–Heitler process from laser wakefield accelerated electrons interacting with high
materials have velocities close to the laser wakefield. It is possible to accelerate those muons with laser wakefield directly. Therefore for the first time we propose an all-optical ‘Generator and Booster’ scheme to accelerate the produced muons by another laser wakefield to supply a prompt, compact, low cost and controllable muon source in laser laboratories. The trapping and acceleration of muons are analyzed by one-dimensional analytic model and verified by two-dimensional particle-in-cell (PIC) simulation. It is shown that muons can be trapped in a broad energy range and accelerated to higher energy than that of electrons for longer dephasing length. We further extrapolate the dependence of the maximum acceleration energy of muons with the laser wakefield relativistic factor
and the relevant initial energy
. It is shown that a maximum energy up to 15.2 GeV is promising with
on the existing short pulse laser facilities.
There is a dearth of data on the iodine balance studies of Chinese population. In the present study, we aimed to explore the appropriate recommended nutrient intake (RNI) of iodine based on healthy Chinese women. A 4-week study was conducted in twenty-five Chinese euthyroid women. Uniform diets with different iodine contents were provided in two different periods, in which non-iodised salt was given in the first 3 weeks, followed by 1 week of iodised salt administration. The total iodine intake from diet, water and air as well as the total iodine excretion through urine, faeces and respiration were monitored and determined. The sweat iodine loss was also considered. Moreover, the regression curve model was established between the 24 h iodine intake and 24 h iodine excretion. The 24 h iodine intake in the two periods was 194·8 (sd 62·9) and 487·1 (sd 177·3) μg/d, respectively. The 24 h iodine excretion was 130·9 (sd 39·5) and 265·4 (sd 71·8) μg/d, respectively. Both 24 h iodine intake and 24 h iodine excretion of the two periods were significantly different (all P<0·05). The iodised salt contributed approximately 62·7 % of the total daily iodine intake. Moreover, 92·3 % (277/300) of samples were in positive balance, while twenty-three cases were in negative balance. Our data show that the estimated average requirement for iodine was 110·5 μg/d. Therefore, the RNI for iodine to non-pregnant, non-lactating Chinese women was 154·7 μg/d.
In inertial confinement fusion experiments that involve short-laser pulses such as fast ignition (FI), diagnosis of neutrons is usually very challenging because high-intensity γ rays generated by short-laser pulses would mask the much weaker neutron signal. In this paper, fast-response scintillators with low afterglow and gated microchannel plate photomultiplier tubes are combined to build neutron time-of-flight (nTOF) spectrometers for such experiments. Direct-drive implosion experiments of deuterium-gas-filled capsules were performed at the Shenguang-II Upgrade (SG-II-UP) laser facility to study the compressed fuel areal density (〈ρR〉) and evaluate the performance of such nTOF diagnostics. Two newly developed quenched liquid scintillator detectors and a gated ultrafast plastic scintillator detector were used to measure the secondary DT neutrons and primary DD neutrons, respectively. The secondary neutron signals were clearly discriminated from the γ rays from (n, γ) reactions, and the compressed fuel areal density obtained with the yield-ratio method agrees well with the simulations. Additionally, a small scintillator decay tail and a clear DD neutron signal were observed in an integrated FI experiment as a result of the low afterglow of the oxygen-quenched liquid scintillator.
This study quantified the fatty acid profile with emphasis on the stereo-specifically numbered (sn) 2 positional distribution in TAG and the composition of main phospholipids at different lactation stages. Colostrum milk (n 70), transitional milk (n 96) and mature milk (n 82) were obtained longitudinally from healthy lactating women in Shanghai. During lactation, total fatty acid content increased, with SFA dominating in fatty acid profile. A high ratio of n-6:n-3 PUFA was observed as 11:1 over lactation due to the abundance of linoleic acid in Chinese human milk. As the main SFA, palmitic acid showed absolute sn-2 selectivity, while oleic acid, linoleic acid and α-linolenic acid, the main unsaturated fatty acids, were primarily esterified at the sn-1 and sn-3 positions. Nervonic acid and C22 PUFA including DHA were more enriched in colostrum with an sn-2 positional preference. A total of three dominant phospholipids (phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM)) were analysed in the collected samples, and each showed a decline in amount over lactation. PC was the dominant compound followed by SM and PE. With prolonged breast-feeding time, percentage of PE in total phospholipids remained constant, but PC decreased, and SM increased. Results from this study indicated a lipid profile different from Western reports and may aid the development of future infant formula more suitable for Chinese babies.
Electroconvulsive therapy (ECT), an effective antidepressive treatment, is frequently accompanied by cognitive impairment (predominantly memory), usually transient and self-limited. The hippocampus is a key region involved in memory and emotion processing, and in particular, the anterior-posterior hippocampal subregions has been shown to be associated with emotion and memory. However, less is known about the relationship between hippocampal-subregion alterations following ECT and antidepressant effects or cognitive impairments.
Resting-state functional connectivity (RSFC) based on the seeds of hippocampal subregions were investigated in 45 pre- and post-ECT depressed patients. Structural connectivity between hippocampal subregions and corresponding functionally abnormal regions was also conducted using probabilistic tractography. Antidepressant effects and cognitive impairments were measured by the Hamilton Depressive Rating Scale (HDRS) and the Category Verbal Fluency Test (CVFT), respectively. Their relationships with hippocampal-subregions alterations were examined.
After ECT, patients showed increased RSFC in the hippocampal emotional subregion (HIPe) with the left middle occipital gyrus (LMOG) and right medial temporal gyrus (RMTG). Decreased HDRS was associated with increased HIPe-RMTG RSFC (r = −0.316, p = 0.035) significantly and increased HIPe-LMOG RSFC at trend level (r = −0.283, p = 0.060). In contrast, the hippocampal cognitive subregion showed decreased RSFC with the bilateral angular gyrus, and was correlated with decreased CVFT (r = 0.418, p = 0.015 for left; r = 0.356, p = 0.042 for right). No significant changes were found in structural connectivity.
The hippocampal-subregions functional alterations may be specially associated with the antidepressant and cognitive effects of ECT.