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For the omnivorous Cherax quadricarinatus crayfish, plant raw materials can be good alternatives to dietary fish meal (FM). A 56-d feeding trial was conducted in C. quadricarinatus (11·70 (se 0·13) g). Diet with 100 % FM as the protein source was the control. Seven experimental diets were formulated by replacing 75 or 100 % of FM with soyabean meal (SM75, SM100) or cottonseed meal (CM75 and CM100), and a mixture of SM and CM (protein content is 1:1) replacing 50, 75 or 100 % of FM (SC50, SC75 and SC100). Crayfish fed the CM100 and SC100 showed significantly lower weight gain (WG), specific growth rate, trypsin and pepsin activities compared with the control diet. Crayfish in CM100 group showed significantly higher GPx, alanine aminotransferase, aspartate aminotransferase activities and malondialdehyde content than the control. SM100 and CM100 diets can cause slight separation of the peritrophic membrane from the intestinal folds. The pepsin activity of crayfish in SC50 was significantly higher than those in other experimental diets. The highest WG and muscle arginine content were also found in crayfish fed SC50. The relative abundance of Proteobacteria, Unclassified Enterobacteriaceae and Candidatus Bacilloplasma was significantly higher, but Actinobacteriota was significantly lower in SM100, CM100 and SC100 than in control. Microbiota functional prediction indicated that the relative abundance of ‘cell motility’ pathway in crayfish fed CM100 was significantly decreased compared with the control. In conclusion, only half of the FM can be effectively substituted with a mixture of SM and CM (protein content is 1:1) for C. quadricarinatus.
As threats to biodiversity proliferate, establishment and expansion of protected areas have increasingly been advocated in recent decades. In establishing a network of protected areas, recurrent assessments of the biodiversity conservation actually afforded by these areas is required. Gap analysis has been useful to evaluate the sufficiency and performance of protected areas. We surveyed Reeves’s Pheasant Syrmaticus reevesii populations in 2018–2019 across its distribution range in central China to quantify the distribution of habitat suitable for this species. Our goal was to ascertain the current distribution of Reeves’s Pheasant and then identify the gaps in protecting Reeves’s Pheasant of the existing national nature reserve (NNR) network to provide suggestions for improving the conservation of this important species. The existing NNR network encompassed only 17.0% of the habitat suitable for Reeves’s Pheasant. Based on the current distributions of both suitable habitat and NNRs for Reeves’s Pheasant, we suggest most currently unprotected areas comprised moderately suitable habitat for species and should be prioritized in the future. A multiple species approach using Reeves’s Pheasant as a flagship species should be considered to understand the extent of mismatch between the distributions of protected areas and suitable habitat to improve the management effectiveness of NNRs. This case study provides an example of how the development of a conservation reserve network may be based on species distribution and habitat assessments and is useful to conservation efforts in other regions and for other species.
To measure the associations of sociodemographic and behavioural factors with fruit and vegetable consumption among adults in China.
A cross-sectional study.
A 2015 wave of the China Health and Nutrition Survey.
Totally, 11 910 adults aged 18 to 64 years.
Adjusted log binomial regression analyses showed that adults with higher income levels had higher fruit intake than those with low income levels (medium income group, risk ratio (RR): 1·28; 95 % CI: 1·16, 1·41; high income group, RR: 1·58; 95 % CI: 1·43, 1·74). Current smokers had lower fruit intake than non-smokers (RR: 0·86; 95 % CI: 0·77, 0·96). Adults living in southern China had higher vegetable intake (RR: 1·88; 95 % CI: 1·76, 2·01) but lower fruit intake (RR: 0·85; 95 % CI: 0·79, 0·91) than adults in northern China. With increasing age, adults had higher fruit intake (50–64 years, RR: 1·20; 95 % CI: 1·09, 1·33; reference category 18–34 years) and higher vegetable intake (35–49 years, RR: 1·13; 95 % CI: 1·05, 1·22; 50–64 years, RR: 1·22; 95 % CI: 1·13, 1·31).
Our findings identify a range of sociodemographic and behavioural factors associated with fruit and vegetable consumption among Chinese adults. They also point to the need for public health nutrition interventions for socially disadvantaged populations in China.
Dietary salt intake may vary depending on different lifestyles. We aimed to estimate the different salt intakes and evaluate the knowledge and self-awareness about salt among people speaking the Teochew, Teochew–Hakka and Hakka dialects in the Chaoshan region of southern China.
The study followed a cluster sampling of residents in Chaoshan region. General characteristics, lifestyles, health status as well as knowledge and self-awareness related to salt intake were investigated using a questionnaire. Anthropometric variables as well as Na and K excretion in a 24-h urine collection were measured.
Chaoshan region of China.
Four hundred fifteen adults who spoke only one of these three dialects.
The salt intake of adults who spoke the Teochew, Teochew–Hakka and Hakka dialects was 7·19 (interquartile range (IQR) 5·29–10·17), 9·03 (IQR 6·62–11·54) and 10·12 (IQR 7·61–12·82) g/d, respectively, with significant differences between Teochew and Teochew–Hakka speakers and between Teochew and Hakka speakers (both P < 0·05). The Na:K ratio for adults who spoke the three dialects was 3·00 (IQR 2·00–4·11), 3·50 (IQR 2·64–4·82) and 4·52 (IQR 3·35–5·97), respectively, and differed significantly among the groups (all P < 0·05). Multiple linear regression analysis showed increased Na:K ratio associated with hypertension (β = 0·71, P = 0·043) in Hakka speakers. Knowledge and self-awareness about salt intake were poor in this population.
Salt intake was closely related to lifestyles and was higher than the upper limit (5 g/d) recommended by the WHO in adults of Chaoshan, especially those speaking the Hakka dialect.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
An analytical method is proposed to reduce the memory effects and third-order intermodulation distortions for improving the linearity of wideband power amplifier (PA). An excellent linearity can be obtained by reducing the second-harmonic output power levels and reducing the envelope voltage components in the megahertz range. An improved wideband Chebyshev low-pass matching network including the bias network is analyzed and designed to validate the proposed method. The measured results indicate that a wideband high-efficiency linearized PA is realized from 1.35 to 2.45 GHz (fractional bandwidth = 58%) with power added efficiency of 60–78%, power gain of 10.8–12.3 dB, and output power of 40.0–41.2 dBm. For a 20 MHz LTE modulated signal, the adjacent channel leakage ratios (ACLRs) of the proposed PA with digital pre-distortion (DPD) linearization are −55.7 ~ −53.9 dBc across 1.5–2.4 GHz at an average output power of 32.4–33.6 dBm. For a 40 MHz two-carrier LTE modulated signal, the ACLRs of the proposed PA with DPD linearization are −51.1 ~ −48.2 dBc at an average output power of ~30.5 dBm in the frequency range from 1.5 GHz to 2.4 GHz.
This study aimed to determine the effects of supplementing the diet of adult Nile tilapia Oreochromis niloticus with phosphatidylcholine (PC) on growth performance, body composition, fatty acid composition and gene expression. Genetically Improved Farmed Tilapia fish with an initial body weight of 83·1 (sd 2·9) g were divided into six groups. Each group was hand-fed a semi-purified diet containing 1·7 (control diet), 4·0, 6·5, 11·5, 21·3 or 41·0 g PC/kg diet for 68 d. Supplemental PC improved the feed efficiency rate, which was highest in the 11·5 g PC/kg diet. Weight gain and specific growth rate were unaffected. Dietary PC increased PC content in the liver and decreased crude fat content in the liver, viscera and body. SFA and MUFA increased and PUFA decreased in muscle with increasing dietary PC. Cytoplasmic phospholipase A2 and secreted phospholipase A2 mRNA expression were up-regulated in the brain and heart in PC-supplemented fish. PC reduced fatty acid synthase mRNA expression in the liver and visceral tissue but increased expression in muscle. Hormone-sensitive lipase and lipoprotein lipase expression increased in the liver with increasing dietary PC. Growth hormone mRNA expression was reduced in the brain and insulin-like growth factor-1 mRNA expression in liver reduced with PC above 6·5 g/kg. Our results demonstrate that dietary supplementation with PC improves feed efficiency and reduces liver fat in adult Nile tilapia, without increasing weight gain, representing a novel dietary approach to reduce feed requirements and improve the health of Nile tilapia.
The prevalence of CHD has been well described worldwide except in Tibet. This study aimed to illustrate the prevalence and composition of CHD in Tibetan children according to altitude.
Methods and results
In the first part, we prospectively recruited 7088 unselected Tibetan children (4–17 years) from south-west Tibet. The total prevalence of CHD increased from 4.6/1000 below 4200 m to 13.4/1000 above 4700 m, with a female-to-male ratio of 1.3:3.1. The total prevalence and female prevalence of patent ductus arteriosus increased more than 10-fold. Females living above 4700 m had exceptionally high prevalence of patent ductus arteriosus (14.9/1000). The prevalence of atrial septal defect was comparable among different altitudes (3.3–3.8/1000). The prevalence of ventricular septal defect was 1.3/1000 below 4700 m, and no cases were found above this altitude. In the second part, we retrospectively reviewed the clinical data of 383 CHD children in Tibet and 73 children at lower altitudes. The percentage of isolated ventricular septal defect decreased from 54.8 to 3.1%, and the percentage of isolated patent ductus arteriosus increased from 8.2 to 68.4% with elevation. Children living below 4200 m (10.4–13.7%) had a larger proportion of complex CHD than those above this altitude (2.0–3.1%). Of the 20 Tibetan children with complex CHD, 14 (70.0%) lived below 4200 m.
A wide variation in CHD prevalence and composition existed in Tibetan children among different altitudes.
To evaluate the prevalence of vitamin D deficiency and insufficiency, as well as their association with Hb and elevated blood lead levels (BLL) in children in China.
A cross-sectional and 1-year retrospective study.
Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, China.
Children aged from 6 months to 14 years living in south-west China who were taken to physical examinations (January–December 2011).
Of 1218 children included in the study, 25-hydroxyvitamin D (25(OH)D) concentration (mean 33·18 (sd 16·48) ng/ml) was deficient in 21·6 % and insufficient in 27·4 %, which were higher than the prevalence of both anaemia at 8·5 % and elevated BLL (Pb ≥ 10 μg/dl) at 1·8 %, but lower than mildly elevated BLL prevalence (5 μg/dl ≤ Pb < 10 μg/dl) at 56·9 %. There was a negative correlation between 25(OH)D concentration and BLL (r = −0·216, P < 0·001) while no significant relationship was found between 25(OH)D concentration and Hb (r = −0·012, P > 0·05). After multivariable adjustment, the significant predictors of 25(OH)D deficiency and insufficiency were increasing child age especially between 8 and 14 years (OR = 18·29; 95 % CI 10·14, 32·99; P < 0·001) and BLL (OR = 1·01; 95 % CI 1·00, 1·02; P = 0·045).
The prevalence of 25(OH)D deficiency and insufficiency was much higher than that of anaemia or elevated BLL in south-west China, and associated with increasing age and BLL.
In order to detect the molecular mechanism of heterosis in pigs, an mRNA differential display (DD) technique was performed to investigate the differences in gene expression in the longissimus dorsi muscle tissues from Meishan, Meishan×Large White cross and Large White pigs. Fourteen expressed sequence tags (ESTs), differentially expressed between the hybrid and purebred pigs, were isolated and identified through semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Nucleotide sequence analysis revealed that the 14 ESTs are not homologous to any of the known genes or ESTs. These novel ESTs were then deposited in the GenBank database. Tissue expression profile analysis showed that the ESTs were expressed in most tissues, including heart, spleen, liver, kidney, small intestine, ovary and lung, and this also implied that these genes must be important for the life process. Our results indicate the diversity of differential display of genes between the hybrids and purebreds in the Meishan×Large White cross combination. Results also suggest that heterosis in pigs might be derived from the differential expression of many indispensable genes in specific life phases.
The molecular genetic characteristics were evaluated, and the genetic effects of marker loci on heterosis of three traits (birth weight, BWT; average daily gain, ADG; and feed and meat ratio, FMR) were analysed in the experimental pig populations: Yorkshire (Y, n=34), Landrace (L, n=46) and Meishan (M, n=55); Yorkshire×Landrace (YL, n=32) and its reciprocal (LY, n=36), Yorkshire×Meishan (YM, n=82) and its reciprocal (MY, n=47), by 39 microsatellite markers selected from pig chromosomes SSC4, 6, 7, 8 and 13. The results indicated that observed alleles ranged from 2 to 6, average 4.13, observed heterozygosity varied from 0.39 (Y) to 0.58 (YM+MY) and average polymorphism information content (PIC) varied from 0.33 (Y) to 0.5 (YM). There were two loci (sw2155 and sw1037) at which the alleles were fixed in Y and L, and there were three loci (sw2409, sw2454 and sw1691) at which the alleles were fixed in M. The results from heterozygosity and kinship analysis revealed an intrinsic genetic relationship among the seven populations. Furthermore, the results on genetic effect analysis indicate that several marker loci had a significant effect on heterosis of the three traits in the two different F1 crossbred populations (P⩽0.01), for example s0161, swr1130 and sw1856 for BWT, sw1856 and swr2036 for ADG, and sw1302 and swr2036 for FMR. The significant marker loci implied a deep genetic relationship between molecular marker loci and heterosis.
Radiation transfer in low-density foam is influenced by the external
radiation field which impacts on the foam when the size of plasma created
in laboratory is not large to be opatical thick. The radiation transfers
of different photon groups are sensitive probes of the conditions of the
medium through which they propagate. The temporal behavior of photon
groups to which the plasma is optical thin is quite different from that of
photon groups to which the plasma is optical thick. The breakout times of
different photon groups through the foam are distinguishable different in
experiment when we measures them at the end of foam. The multi-group
supersonic radiation transfer behavior in low-density foam is studied both
by multi-group transfer numerical simulation and experiments. Two
characteristic photon groups are chosen to do experimental research on the
multi-group transfer behavior in low-density CH foam. A time-resolved
chromatic streaked X-ray spectrometer measure the breakout of the two
photon group from the far end of the foam cylinder. The distinguishable
transfer time delay between two groups is observed.
In order to reveal the molecular basis of heterosis, Large White (LW), an introduced European pig breed, and Meishan (MS), a Chinese indigenous pig breed, were selected to hybridize directly and reciprocally in the present experiment. mRNA differential display (DD) technique was performed to identify genes that were differentially expressed in the backfat tissues of hybrids (LW×MS, MS×LW) and purebred (LW×LW, MS×MS) pigs. The ten anchor primers in combination with ten arbitrary primers (100 sets in total) were used and nearly 1500 reproducible bands were observed in polyacrylamide gels. The 40 differentially displayed bands were selected for cloning and sequencing. Thirty-six out of 40 expressed sequence tags (ESTs) proved to be novel and the sequences were submitted to GenBank (accession No. CV507051-CV507087); the other four showed similarity to known genes published in GenBank. Three among 36 novel ESTs were chosen for further identification with semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The result showed that two ESTs were differentially expressed, and the third showed no obvious difference between hybrids and purebreds. In order to reduce the percentage of false-positive DD, RNA pools of four types of pigs were constructed, by mixing samples from six pigs of the same genotype, and subjected to DD. Stringent annealing temperature was applied and only bands that could be repeated in duplicate PCR were used for further study. The results showed that the expression pattern of these 36 ESTs differed among the four genotypes of pigs, suggesting that the genes corresponding to these differentially expressed ESTs might be related to the heterosis occurring in fat tissue.
The β-glucosidase gene has important effects on alcoholic aroma precursors and insect resistance of the tea plant [Camellia sinensis (L.) O. Kutze]. The complete cDNA sequence of β-glucosidase of the tea plant was cloned; its full length was 1475 bp, and shared 40–60% similarity with corresponding parts of the nucleotide sequence of β-glucosidase gene from other plants. Its secondary structure contains 14.33% α-helix, 25.43% β-pleated sheet and many functional amino acid domains. The β-glucosidase gene was cloned into the pET-32a expression system and expressed at high-efficiently in Escherichia coli BL21 (DE3); the molecular weight of expressed fusion protein was 63 kDa. The results of enzymic reaction showed that the fusion protein possessed normal bioactivity, and it could catalyse the dehydration of the glycosidic bond. The soluble fusion protein was expressed mainly in the cytoplasm.
In this paper, a simplified and direct computation method formulated by the fixed coordinate system and relative meridian concept in conjunction with vector algebra is developed to deal with the classical problems of celestial navigation. It is found that the proposed approach, the Simultaneous Equal-altitude Equation Method (SEEM), can directly calculate the Astronomical Vessel Position (AVP) without an additional graphical procedure. The SEEM is not only simpler than the matrix method but is also more straightforward than the Spherical Triangle Method (STM). Due to tedious computation procedures existing in the commonly used methods for determining the AVP, a set of optimal computation procedures for the STM is also suggested. In addition, aimed at drawbacks of the intercept method, an improved approach with a new computation procedure is also presented to plot the celestial line of position without the intercept. The improved approach with iteration scheme is used to solve the AVP and validate the SEEM successfully. Methods of solving AVP problems are also discussed in detail. Finally, a benchmark example is included to demonstrate these proposed methods.
Regeneration of sweet potato (Ipomoea batatas cv. Lizixiang) transgenic plants with oryzacystatin-I (OCI) gene was achieved using an Agrobacterium tumefaciens-mediated method. A. tumefaciens strain LBA4404, harbouring a binary vector pBinh with neomycin phosphotransferase II and OCI genes, was used. After 3 days of subculture, Lizixiang embryogenic suspension cultures were co-cultivated with LBA4404 (OD600nm=0.5) for 4 days. Next, the infected suspension cultures were first cultured for 5 days in MS medium with 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) and 300 mg/l carbencillin (Carb) but without kanamycin (Kan) and then transferred to MS medium supplemented with 2 mg/l 2,4-D, 50 mg/l Kan and 300 mg/l Carb for the selection culture. Four weeks after selection, 200 Kan-resistant cell aggregates (∼1 mm in size) from the embryogenic suspension cultures were transferred to MS solid medium supplemented with 2 mg/l 2,4-D, 50 mg/l Kan and 300 mg/l Carb, and eight embryogenic calluses were obtained. After transferring to MS medium supplemented with 1 mg/l ABA, 50 mg/l Kan and 100 mg/l Carb, these embryogenic calluses formed 13 plantlets via somatic embryogenesis. PCR and PCR–Southern blot analysis indicated that seven of the 13 plantlets were transgenic.
Examples of novel solid state devices are presented, together with descriptions of their applicability to the diagnosis of laboratory, processing and fusion plasmas. GaAs varactor diodes can be arranged in large monolithic grid arrays, forming millimeter wave frequency multiplier based sources and high speed switches, or embedded in transmission lines to provide a true time delay for phased antenna array beam steering. Micro-electromechanical systems (MEMS) switches are exciting new devices with numerous applications, including low loss millimeter wave switches, phase shifters and mechanically tunable structures.
α–Si3N4 whiskers were fabricated first through combustion synthesis (CS) technology. The as-synthesized crystals with  as the elongated axis contain a large amount of linear defects including (a + b)-type, (a + b + c)-type, and c-type of dislocations. The growth of α–Si3N4 whiskers is mainly controlled by vapor-condensation (VC) mechanism. Special additive plays an important role in promoting the growth of α–Si3N4 whiskers and suppressing the phase transformation of α–Si3N4 to β–Si3N4.
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