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Compulsive behaviors in obsessive-compulsive disorder (OCD) have been related to impairment within the associative cortical-striatal system connecting the caudate and prefrontal cortex that underlies consciously-controlled goal-directed learning and behavior. However, little is known whether this impairment may serve as a biomarker for vulnerability to OCD.
Using resting-state functional magnetic resonance imaging (fMRI), we employed Granger causality analysis (GCA) to measure effective connectivity (EC) in previously validated striatal sub-regions, including the caudate, putamen, and the nucleus accumbens, in 35 OCD patients, 35 unaffected first-degree relatives and 35 matched healthy controls.
Both OCD patients and their first-degree relatives showed greater EC than controls between the left caudate and the orbital frontal cortex (OFC). Both OCD patients and their first-degree relatives showed lower EC than controls between the left caudate and lateral prefrontal cortex. These results are consistent with findings from task-related fMRI studies which found impairment in the goal-directed system in OCD patients.
The same changes in EC were present in both OCD patients and their unaffected first-degree relatives suggest that impairment in the goal-directed learning system may be a biomarker for OCD.
An experiment was conducted to determine the effects of supplementing different amounts of daidzein in a diet on the growth performance, blood biochemical parameters and meat quality of finishing beef cattle. Thirty finishing Xianan steers were distributed in three groups equilibrated by weight and fed three different dietary treatments (concentrate ratio = 80%): (1) control; (2) 500 mg/kg daidzein and (3) 1000 mg/kg daidzein, respectively. Steers were slaughtered after an 80-day feeding trial. Results showed that daidzein supplementation had no effect on the final body weight, average daily gain and feed conversion rate of steers. Steers fed with 1000 mg/kg daidzein had greater dry matter intake than those fed with control diets. Compared with the control group, the 1000 mg/kg daidzein group had a higher fat thickness, lower shear force and lightness. The pH, drip loss, cooking loss, redness (a*), yellowness (b*), moisture, ash, crude protein and intramuscular fat of the Longissimus dorsi muscle were unaffected by daidzein supplementation. Compared with the control group, the 1000 mg/kg daidzein group significantly increased the serum concentrations of insulin, free fatty acid and Glutamic-pyruvic transaminase. The 500 mg/kg daidzein group significantly increased the serum concentration of tetraiodothyronine compared with the control group. Supplemental daidzein did not affect the blood antioxidant ability and blood immune parameters in serum. In conclusion, daidzein supplementation above 500 mg/day modifies feed intake and metabolic and hormonal profile, with positive and negative effects on meat quality.
Relatively little is known about the physical mechanisms that drive the dynamics of the East Antarctic outlet glaciers. Here we conduct a remote-sensing investigation of the Polar Record Glacier (PRG), East Antarctica to analyze its ice flow acceleration, ice front variations and ice surface melting. Ice flow speeds at PRG increased by up to 15% from 2005 to 2015, with substantial interannual fluctuations. The ice velocities also showed seasonal variations, accelerating by up to 9% between September and January. Multiple mechanisms contribute to the observed seasonal variations: the initial acceleration may result from the lost back-stress provided by the sea ice in the austral spring and the later speedup relate to the surface meltwater that leads to weakened ice shelf and shear margins. The sensitivity of the PRG to oceanic forcing is confirmed by comparing the secular ice velocity increases with ocean temperatures. These measurements suggest that the dynamics of East Antarctic ice shelves are sensitive to melt at both the surface and base, at a range of timescales.
Cognitive impairment in late-life depression is common and associated with a higher risk of all-cause dementia. Late-life depression patients with comorbid cardiovascular diseases (CVDs) or related risk factors may experience higher risks of cognitive deterioration in the short term. We aim to investigate the effect of CVDs and their related risk factors on the cognitive function of patients with late-life depression.
A total of 148 participants were recruited (67 individuals with late-life depression and 81 normal controls). The presence of hypertension, coronary heart disease, diabetes mellitus, or hyperlipidemia was defined as the presence of comorbid CVDs or related risk factors. Global cognitive functions were assessed at baseline and after a one-year follow-up by the Mini-Mental State Examination (MMSE). Global cognitive deterioration was defined by the reliable change index (RCI) of the MMSE.
Late-life depression patients with CVDs or related risk factors were associated with 6.8 times higher risk of global cognitive deterioration than those without any of these comorbidities at a one-year follow-up. This result remained robust after adjusting for age, gender, and changes in the Hamilton Depression Rating Scale (HAMD) scores.
This study suggests that late-life depression patients with comorbid CVDs or their related risk factors showed a higher risk of cognitive deterioration in the short-term (one-year follow up). Given that CVDs and their related risk factors are currently modifiable, active treatment of these comorbidities may delay rapid cognitive deterioration in patients with late-life depression.
To revise an abbreviated version of the Silhouettes subtest of the Visual Object and Space Perception (VOSP) battery in order to recognize mild cognitive impairment (MCI) and determine the optimal cutoffs to differentiate among cognitively normal controls (NC), MCI, and Alzheimer’s Disease (AD) in the Chinese elderly.
A cross-sectional validation study.
Huashan Hospital, Shanghai, China.
A total of 591 participants: Individuals with MCI (n = 211), AD (n = 139) and NC (n = 241) were recruited from the Memory Clinic, Huashan Hospital, Shanghai, China.
Baseline neuropsychological battery (including VOSP) scores were collected from firsthand data. An abbreviated version of silhouettes test (Silhouettes-A) was revised from the original English version more suitable for the elderly, including eight silhouettes of animals and seven silhouettes of inanimate objects, with a score ranging from 0 to 15.
Silhouettes-A was an effective test to screen MCI in the Chinese elderly with good sensitivity and specificity, similar to the Montreal cognitive assessment and superior to other single tests reflecting language, spatial, or executive function. However, it had no advantage in distinguishing MCI from AD. The corresponding optimal cutoff scores of Silhouettes-A were 10 for screening MCI and 8 for AD.
Silhouettes-A is a quick, simple, sensitive, and dependable cognitive test to distinguish among NC, MCI, and AD patients.
(1 − x)Ba(Mg1/3Ta2/3)O3–xBa(Co1/3Nb2/3)O3 (BMT–BCN, x = 0.0, 0.20, 0.25, 0.30, 0.40) ceramics were prepared using the traditional solid-state reaction method. X-ray diffraction patterns have shown that the intensities of (001) and (100) super-lattices decrease with the increase in the BCN content. Seven main Raman vibrational modes are observed, assigned, and illustrated, in particular. Raman shifts of Eg(O) modes and the FWHM values of F2g(O)/A1g(O) modes have close relationship with the dielectric properties. The calculated values by the four-parameter semiquantum model based on IR reflectivity match well with the measured data (@3.8 GHz), which means that most of dielectric contribution to the system may be ascribed to the absorption of structural phononic oscillations at the infrared region, and the contribution from the scattering of the defective phonons is small. The contributions of each vibrational mode on the dielectric responses were investigated in detail, indicating that the low-frequency modes (A2u(1) and Eu(1)) have a decisive role to the dielectric properties.
Some rare microscopic cycloneuralians are present in the Cambrian of South China, represented by Eopriapulites and Eokinorhynchus (both early Cambrian), fossil embryos of Markuelia (middle to late Cambrian), and palaeoscolecids (early to late Cambrian). Among them, palaeoscolecids are relatively diverse and abundant. Here, we describe new material of three-dimensionally phosphatized and microscopic cycloneuralians from the Paibian Stage of Wangcun Lagerstätte, western Hunan, South China. New material includes fossil embryos assignable to Markuelia sp., two other types of fossil embryos, and three species of palaeoscolecids, including Dispinoscolex decorus Duan, Dong, and Donoghue, 2012, Schistoscolex hunanensis Duan, Dong, and Donoghue, 2012, and Austroscolex sinensis new species. The palaeoscolecid fragments differ mainly in size and armor of the trunk annuli. Since Eokinorhynchus and Eopriapulites occurred the earliest among the Cambrian cycloneuralians, it is proposed here that: (1) cycloneuralians originated in the Cambrian Fortunian small shelly faunas rather than in the early Cambrian macrobenthos, (2) ancestral cycloneuralians may have simple trunk armor, and (3) Eopriapulites represents an ancestral cycloneuralian.
Carnitine has been reported to improve growth performance and reduce body lipid content in fish. Thus, we hypothesised that carnitine supplementation can improve growth performance and reduce lipid content in the liver and muscle of yellow catfish (Pelteobagrus fulvidraco), a commonly cultured freshwater fish in inland China, and tested this hypothesis in the present study. Diets containing l-carnitine at three different concentrations of 47 mg/kg (control, without extra carnitine addition), 331 mg/kg (low carnitine) and 3495 mg/kg (high carnitine) diet were fed to yellow catfish for 8 weeks. The low-carnitine diet significantly improved weight gain (WG) and reduced the feed conversion ratio (FCR). In contrast, the high-carnitine diet did not affect WG and FCR. Compared with the control diet, the low-carnitine and high-carnitine diets increased lipid and carnitine contents in the liver and muscle. The increased lipid content in the liver could be attributed to the up-regulation of the mRNA levels of SREBP, PPARγ, fatty acid synthase (FAS) and ACCa and the increased activities of lipogenic enzymes (such as FAS, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and malic enzyme) and to the down-regulation of the mRNA levels of the lipolytic gene CPT1A. The increased lipid content in muscle could be attributed to the down-regulation of the mRNA levels of the lipolytic genes CPT1A and ATGL and the increased activity of lipoprotein lipase. In conclusion, in contrast to our hypothesis, dietary carnitine supplementation increased body lipid content in yellow catfish.
The Rb/Sr ratio of lake sediments has been demonstrated to be a potential indicator of chemical weathering by increasing work. However, Rb and Sr in lake sediments are derived from both chemical weathering and physical erosion. Rb and Sr of different forms in lake sediments may record different environmental processes and information. In this study, the variation patterns of Rb and Sr of different forms in sediments of Daihai Lake were investigated. The results show that Rb and Sr of different forms display noticeably different variation patterns due to their different sources and associated environmental processes. Using the Rb/Sr ratios of bulk lake sediments to reflect chemical weathering is not accurate. The non-residual Sr of the sediments without detrital carbonates, representing the Sr leached from the catchment, can be used as an index of chemical weathering because the weathering of Sr minerals is very sensitive to climate change, and the non-residual Sr content of the sediment is determined more by Sr2 + influx than by the physicochemical conditions of lake water. The correspondence between the non-residual Sr and TIC/TOC in Daihai Lake also indicates that the non-residual Sr of the sediments is a good indicator of chemical weathering in the catchment.
Bombardment of silicon surfaces by low-energy nitrogen ions has been investigated as a possible process for growing films of silicon nitride at relatively low temperature(<500°C). Broad ion beams of energy 300–1200eV have been used to grow ultrathin silicon nitride films. Film thickness and chemical states are analyzed using ellipsometery, X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy(AES). As a result, thicknesses dependence on ion energy, substrate temperature and implantation time have been investigated. The thicknesses of films obtained appear to increase with ion energy in the range from 300 to 1200eV, and with time of bombardment. The thicknesses are also observed to vary slightly with substrate temperature. The growth mechanism has also been investigated and discussed. The average activation energy of nitridation rates is about 3.5meV which indicates nonthermal process kinetics, compared to an activation energy of 0.2–0.6eV for thermal nitridation. AES results show that the atomic ratio [N]/[Si] is about 1.5, larger than that of pure Si3N4. All the analyses show that silicon nitride films of about 60Å thickness have been grown on silicon by low-energy ion beam nitridation.
It is well known that noctuid moths respond to ultrasound frequencies produced by insectivorous bats performing a series of evasive maneuvers such as loops, dives, rolls, and turns. Certain ultrasound frequencies may be considered an environmental stress factor for these moths, causing physiological and behavioral effects. We investigated changes in acetylcholinesterase activity of Helicoverpa armigera (Hübner) exposed to ultrasound produced from a commercial device (LHC20). Our results indicated that stress effects on acetylcholinesterase activity resulting from exposure to ultrasound do not differ according to sex, but effects on different developmental stages of H. armigera differ significantly depending on duration of exposure. Enzyme activity increased in adults after 20 min exposure to ultrasound and decreased in pupae after 30 and 50 min exposure. Enzyme activity in larvae was reduced after 20 min and increased after 40 and 60 min. The results of this study also indicate that stress caused by exposure to ultrasound could modulate the cholinergic system in H. armigera.
This study was undertaken to investigate whether low frequency magnetic
fields can affect the characteristic of cancer cells. To achieve this, HL-60 cells were exposed to 20 mT, 50 Hz sinusoidal magnetic field and the cell
viability, cell cycle phase distribution, DNA ladder and apoptotic
morphology between control and exposed cells were examined. The results
demonstrated that magnetic field had pronounced inhibition effects on cell
growth, and small but significant changes in cell cycle phase can be
observed. Internucleosomal DNA fragmentation and morphological changes after
exposure indicate that the magnetic field induces apoptosis in HL-60 cells.
The results also indicate that the growth-inhibitory property of MF on HL-60 cell growth was mainly due to the induction of apoptosis.
The construction of two cDNA libraries from young shoots of tea plant [Camellia sinensis cv. Longjing 43 and Anji Baicha], the sequencing of Longjing 43 cDNA clones and the analysis of expressed sequence tags (ESTs) are reported. Totally, 4320 clones from the cDNA library of Longjing 43 were sequenced, and 2963 useful sequences were obtained, corresponding to 68.6% of clones. A total of 416 clones shorter than 150 bp and 863 repeated clones were excluded, the first 1684 valid tea plant ESTs were generated. Most of the ESTs were between 300 and 700 bp, with an average of 478 bp. Six hundred and seven ESTs with known function or putative function were identified by BlastN searches against the National Center of Biotechnology Institute (NCBI) non-redundant nucleotide databases, corresponding to more than 130 functional genes in the tea plant. The rest, 1077 ESTs, were novel gene partial or full sequences. The results indicated that EST sequencing was a rapid and effective approach to identification of novel functional genes for tea plant.
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