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.
Enhancing the supply of arginine (Arg), a semi-essential amino acid, has positive effects on immune function in dairy cattle experiencing metabolic stress during early lactation. Our objective was to determine the effects of Arg supplementation on biomarkers of liver damage and inflammation in cows during early lactation. Six Chinese Holstein lactating cows with similar BW (508 ± 14 kg), body condition score (3.0), parity (4.0 ± 0), milk yield (30.6 ± 1.8 kg) and days in milk (20 ± days) were randomly assigned to three treatments in a replicated 3 × 3 Latin square design balanced for carryover effects. Each period was 21 days with 7 days for infusion and 14 days for washout. Treatments were (1) Control: saline; (2) Arg group: saline + 0.216 mol/day l-Arg; and (3) Alanine (Ala) group: saline + 0.868 mol/day l-Ala (iso-nitrogenous to the Arg group). Blood and milk samples from the experimental cows were collected on the last day of each infusion period and analyzed for indices of liver damage and inflammation, and the count and composition of somatic cells in milk. Compared with the Control, the infusion of Arg led to greater concentrations of total protein, immunoglobulin M and high density lipoprotein cholesterol coupled with lower concentrations of haptoglobin and tumor necrosis factor-α, and activity of aspartate aminotransferase in serum. Infusion of Ala had no effect on those biomarkers compared with the Control. Although milk somatic cell count was not affected, the concentration of granulocytes was lower in response to Arg infusion compared with the Control or Ala group. Overall, the biomarker analyses indicated that the supplementation of Arg via the jugular vein during early lactation alleviated inflammation and metabolic stress.
The seasonality of individual influenza subtypes/lineages and the association of influenza epidemics with meteorological factors in the tropics/subtropics have not been well understood. The impact of the 2009 H1N1 pandemic on the prevalence of seasonal influenza virus remains to be explored. Using wavelet analysis, the periodicities of A/H3N2, seasonal A/H1N1, A/H1N1pdm09, Victoria and Yamagata were identified, respectively, in Panzhihua during 2006–2015. As a subtropical city in southwestern China, Panzhihua is the first industrial city in the upper reaches of the Yangtze River. The relationship between influenza epidemics and local climatic variables was examined based on regression models. The temporal distribution of influenza subtypes/lineages during the pre-pandemic (2006–2009), pandemic (2009) and post-pandemic (2010–2015) years was described and compared. A total of 6892 respiratory specimens were collected and 737 influenza viruses were isolated. A/H3N2 showed an annual cycle with a peak in summer–autumn, while A/H1N1pdm09, Victoria and Yamagata exhibited an annual cycle with a peak in winter–spring. Regression analyses demonstrated that relative humidity was positively associated with A/H3N2 activity while negatively associated with Victoria activity. Higher prevalence of A/H1N1pdm09 and Yamagata was driven by lower absolute humidity. The role of weather conditions in regulating influenza epidemics could be complicated since the diverse viral transmission modes and mechanism. Differences in seasonality and different associations with meteorological factors by influenza subtypes/lineages should be considered in epidemiological studies in the tropics/subtropics. The development of subtype- and lineage-specific prevention and control measures is of significant importance.
Rabies is one of the major public health problems in China, and the mortality rate of rabies remains the highest among all notifiable infectious diseases. A meta-analysis was conducted to investigate the post-exposure prophylaxis (PEP) vaccination rate and risk factors for human rabies in mainland China. The PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese Science and Technology Periodical and Wanfang databases were searched for articles on rabies vaccination status (published between 2007 and 2017). In total, 10 174 human rabies cases from 136 studies were included in this meta-analysis. Approximately 97.2% (95% confidence interval (CI) 95.1–98.7%) of rabies cases occurred in rural areas and 72.6% (95% CI 70.0–75.1%) occurred in farmers. Overall, the vaccination rate in the reported human rabies cases was 15.4% (95% CI 13.7–17.4%). However, among vaccinated individuals, 85.5% (95% CI 79.8%–83.4%) did not complete the vaccination regimen. In a subgroup analysis, the PEP vaccination rate in the eastern region (18.8%, 95% CI 15.9–22.1%) was higher than that in the western region (13.3%, 95% CI 11.1–15.8%) and this rate decreased after 2007. Approximately 68.9% (95% CI 63.6–73.8%) of rabies cases experienced category-III exposures, but their PEP vaccination rate was 27.0% (95% CI 14.4–44.9%) and only 6.1% (95% CI 4.4–8.4%) received rabies immunoglobulin. Together, these results suggested that the PEP vaccination rate among human rabies cases was low in mainland China. Therefore, standardised treatment and vaccination programs of dog bites need to be further strengthened, particularly in rural areas.
The gastrointestinal tract (GIT) of animals is capable of sensing various kinds of nutrients via G-protein coupled receptor-mediated signaling transduction pathways, and the process is known as ‘gut nutrient chemosensing’. GPR40, GPR41, GPR43 and GPR119 are chemoreceptors for free fatty acids (FFAs) and lipid derivatives, but they are not well studied in small ruminants. The objective of this study is to determine the expression of GPR40, GPR41, GPR43 and GPR119 along the GIT of kid goats under supplemental feeding (S) v. grazing (G) during early development. In total, 44 kid goats (initial weight 1.35±0.12 kg) were slaughtered for sampling (rumen, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum) between days 0 and 70. The expression of GPR41 and GPR43 were measured at both mRNA and protein levels, whereas GPR40 and GPR119 were assayed at protein level only. The effects of age and feeding system on their expression were variable depending upon GIT segments, chemoreceptors and expression level (mRNA or protein), and sometimes feeding system × age interactions (P<0.05) were observed. Supplemental feeding enhanced expression of GPR40, GPR41 and GPR43 in most segments of the GIT of goats, whereas G enhanced expression of GPR119. GPR41 and GPR43 were mainly expressed in rumen, abomasum and cecum, with different responses to age and feeding system. GPR41 and GPR43 expression in abomasum at mRNA level was greatly (P<0.01) affected by both age and feeding system; whereas their expression in rumen and abomasum at protein level were different, feeding system greatly (P<0.05) affected GPR41 expression, but had no effect (P>0.05) on GPR43 expression; and there were no feeding system×age interactions (P>0.05) on GPR41 and GPR43 protein expression. The expression of GPR41 and GPR43 in rumen and abomasum linearly (P<0.01) increased with increasing age (from days 0 to 70). Meanwhile, age was the main factor affecting GPR40 expression throughout the GIT. These outcomes indicate that age and feeding system are the two factors affecting chemoreceptors for FFAs and lipid derivatives expression in the GIT of kids goats, and S enhanced the expression of chemoreceptors for FFAs, whereas G gave rise to greater expression of chemoreceptors for lipid derivatives. Our results suggest that enhanced expression of chemoreceptors for FFAs might be one of the benefits of early supplemental feeding offered to young ruminants during early development.
Records of absenteeism from primary schools are valuable data for infectious diseases surveillance. However, the analysis of the absenteeism is complicated by the data features of clustering at zero, non-independence and overdispersion. This study aimed to generate an appropriate model to handle the absenteeism data collected in a European Commission granted project for infectious disease surveillance in rural China and to evaluate the validity and timeliness of the resulting model for early warnings of infectious disease outbreak. Four steps were taken: (1) building a ‘well-fitting’ model by the zero-inflated Poisson model with random effects (ZIP-RE) using the absenteeism data from the first implementation year; (2) applying the resulting model to predict the ‘expected’ number of absenteeism events in the second implementation year; (3) computing the differences between the observations and the expected values (O–E values) to generate an alternative series of data; (4) evaluating the early warning validity and timeliness of the observational data and model-based O–E values via the EARS-3C algorithms with regard to the detection of real cluster events. The results indicate that ZIP-RE and its corresponding O–E values could improve the detection of aberrations, reduce the false-positive signals and are applicable to the zero-inflated data.
Thousand Island Lake (TIL) is a typical fragmented landscape and an ideal model to study ecological effects of fragmentation. Partial fragments of the mitochondrial cytochrome oxidase subunit I gene of 23 island populations of Dendrolimus punctatus in TIL were sequenced, 141 haplotypes being identified. The number of haplotypes increased significantly with the increase in island area and shape index, whereas no significant correlation was detected between three island attributes (area, shape and isolation) and haplotype diversity. However, the correlation with number of haplotypes was no longer significant when the ‘outlier’ island JSD (the largest island) was not included. Additionally, we found no significant relationship between geographic distance and genetic distance. Geographic isolation did not obstruct the gene flow among D. punctatus populations, which might be because of the high dispersal capacity of this pine moth. Fragmentation resulted in the conversion of large and continuous habitats into isolated, small and insular patches, which was the primary effect on the genetic diversity of D. punctatus in TIL. The conclusion to emphasize from our research is that habitat fragmentation reduced the biological genetic diversity to some extent, further demonstrating the importance of habitat continuity in biodiversity protection.
Four complete platysiagid fish specimens are described from the Luoping Biota, Anisian (Middle Triassic), Yunnan Province, southwest China. They are small fishes with bones and scales covered with ganoine. All characters observed, such as nasals meeting in the midline, a keystone-like dermosphenotic, absence of post-rostral bone, two infraorbitals between dermosphenotic and jugal, large antorbital, and two postcleithra, suggest that the new materials belong to a single, new Platysiagum species, P. sinensis sp. nov. Three genera are ascribed to Platysiagidae: Platysiagum, Helmolepis and Caelatichthys. However, most specimens of the first two genera are imprints or fragmentary. The new, well-preserved specimens from the Luoping Biota provide more detailed anatomical information than before, and thus help amend the concept of the Platysiagidae. The Family Platysiagidae was previously classed in the Perleidiformes. Phylogenetic analysis indicates that the Platysiagidae is a member of basal Neopterygii, and its origin seems to predate that of Perleidiformes. Moreover, platysiagid fishes are known from the Middle Triassic of the western Tethys region. The newly found specimens of platysiagids from Luoping provide additional evidence that both eastern and western sides of the Tethys Ocean were biogeographically more connected than previously thought.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
Iron-deficiency anemia is a public health concern that frequently occurs in pregnant mammals and neonatal offspring. Ferrous N-carbamylglycinate chelate (Fe-CGly) is a newly designed iron fortifier with proven effects in iron-deficient rats and weanling piglets. However, the effects of this new compound on pregnant mammals are unknown. Therefore, this experiment was conducted to evaluate the effects of Fe-CGly on sow reproductive performance and iron status of both sows and neonatal piglets. A total of 40 large-white sows after second parity were randomly assigned to two groups (n=20). They were receiving a diet including 80 mg Fe/kg as FeSO4 or Fe-CGly, respectively, from day 85 of gestation to parturition. The serum (day 110 of pregnancy) and placentas of sows were sampled. Litter size, mean weight of live born piglets, birth (live) litter weight, number of live born piglets, and the number of still-born piglets, mummies, and weak-born piglets were recorded. Once delivered, eight litters were randomly selected from the 20 litters per treatment, and one new-born male piglet (1.503±0.142 kg) from each selected litter was slaughtered within 3 h after birth from the selected litters, without colostrum ingestion. The serum, longissimus muscle, liver and kidneys of the piglets were collected. The iron status of the serum samples and the messenger RNA level of iron-related genes in the placenta, liver and kidney were analyzed. The results showed that litter weight of live born piglets was higher (P=0.030) in the Fe-CGly group (19.86 kg) than in the FeSO4 group (17.34 kg). Fe-CGly significantly increased placental iron concentration (P<0.05) of sows. It also significantly increased iron saturation and reduced the total iron-binding capacity of piglets (P<0.05) at birth. However, the results revealed that supplementation of Fe-CGly in sows reduced liver and kidney iron concentration of neonatal piglets (P<0.05), indicating decreased iron storage. In addition, the concentration of iron in the colostrum was not significantly changed. Therefore, the present results suggested that replacement of maternal FeSO4 supplement with Fe-CGly in the late-gestating period for sows could improve litter birth weight, probably via enhanced iron transportation in the placenta.
Robust time-averaged molecular dynamics has been developed to calculate finite-temperature elastic constants of a single crystal. We find that when the averaging time exceeds a certain threshold, the statistical errors in the calculated elastic constants become very small. We applied this method to compare the elastic constants of Pd and PdH0.6 at representative low (10 K) and high (500 K) temperatures. The values predicted for Pd match reasonably well with ultrasonic experimental data at both temperatures. In contrast, the predicted elastic constants for PdH0.6 only match well with ultrasonic data at 10 K; whereas, at 500 K, the predicted values are significantly lower. We hypothesize that at 500 K, the facile hydrogen diffusion in PdH0.6 alters the speed of sound, resulting in significantly reduced values of predicted elastic constants as compared to the ultrasonic experimental data. Literature mechanical testing experiments seem to support this hypothesis.
Field surveys indicate that host population size, rather than density, is the most important determinant of monogenean infection dynamics. To verify this prediction, epidemic parameters were monitored for 70 days at five host population sizes held at constant density using a goldfish – Gyrodactylus kobayashii laboratory model. During the first 20 days, the rate of increase of prevalence and mean abundance was faster in small host populations. Total mean prevalence and total mean abundance throughout the experiment were not significantly affected by host population sizes. Higher transmission rates were detected in larger host populations. However, there were no significant differences in effective contact rates among the five host populations on each sampling day during the first 20 days, implying that contact rates may be saturated at a sufficiently high host density. These results demonstrate that the epidemic occurs more quickly in smaller host populations at the beginning of the experiment. However, the epidemic is independent of the host population size due to the similar effective contact rates in the five population sizes. Significant negative influence of the initial body condition (Kn) of uninfected goldfish on total mean abundance of parasites suggests that susceptibility of hosts is also a determinant of parasite transmission.
Odorant-binding proteins (OBPs) play a fundamental role in insect olfaction. In recent years, Galeruca daurica (Joannis) (Coleoptera: Chrysomelidae) has become one of the most important insect pests in the Inner Mongolian grasslands of China. This pest only feeds on the species of Allium plants, implying the central role of olfaction in its search for specific host plants. However, the olfaction-related proteins have not been investigated in this beetle. In this study, we identified 29 putative OBP genes, namely GdauOBP1–29, from the transcriptome database of G. daurica assembled in our laboratory by using RNA-Seq. All 29 genes had the full-length open reading frames except GdauOBP29, encoding proteins in length from 119 to 202 amino acids with their predicted molecular weights from 12 to 22 kDa with isoelectric points from 3.88 to 8.84. Predicted signal peptides consisting of 15–22 amino acid residues were found in all except GdauOBP6, GdauOBP13 and GdauOBP29. The amino acid sequence identity between the 29 OBPs ranged 8.33–71.83%. GdauOBP1–12 belongs to the Classic OBPs, while the others belong with the Minus-C OBPs. Phylogenetic analysis indicated that GdauOBPs are the closest to CbowOBPs from Colaphellus bowringi. RT-PCR and qRT-PCR analyses showed that all GdauOBPs were expressed in adult antennae, 11 of which with significant differences in their expression levels between males and females. Most GdauOBPs were also expressed in adult heads (without antennae), thoraxes, abdomens, legs and wings. Moreover, the expression levels of the GdauOBPs varied during the different development stages of G. daurica with most GdauOBPs expressed highly in the adult antennae but scarcely in eggs and pupae. These results provide insights for further research on the molecular mechanisms of chemical communications in G. daurica.
Omics research has indicated that heat shock protein 70 (HSP70) is a potential biomarker of meat quality. However, the specific changes and the potential role of HSP70 in postmortem meat quality development need to be further defined. In this study, Arbor Acres broiler chickens (n=126) were randomly categorized into three treatment groups of unstressed control (C), 0.5-h transport (T) and subsequent water shower spray following transport (T/W). Each treatment consisted of six replicates with seven birds each. The birds were transported according to a designed protocol. The pectoralis major (PM) muscles of the transport-stressed broilers were categorized as normal and pale, soft and exudative (PSE)-like muscle samples according to L* and pH24 h values to test the expression and location of HSP70. Results revealed that the activities of plasma creatine kinase and lactate dehydrogenase increased significantly (P<0.05) in normal and PSE-like muscle samples after transportation. The mRNA expression of HSP70 in normal muscle samples increased significantly (P<0.05) compared with that in the controls after stress. The protein expression of HSP70 increased significantly in normal muscle samples and decreased significantly (P<0.05) in PSE-like muscles. Immuno-fluorescence showed that HSP70 was present in the cytoplasm and on surface membranes of PM muscle cells in the normal samples following stress. Meanwhile, HSP70 was present on the surface membranes and extracellular matrix but was barely visible in the cytoplasm of the PSE-like samples. Principal component analysis showed high correlations between HSP70 and meat quality and stress indicators. In conclusion, this research suggests that the variation in HSP70 expression may provide a novel insight into the pathways underlying meat quality development.
The study investigates three-dimensional kinematics of lower limb for female Chinese population during normal squatting activity. 25 young female and 25 elder female Chinese subjects were recruited. With each subject's data collected, the means of three-dimensional rotation angles of knee, hip, and ankle joints of those two groups were calculated and analyzed. Measured results showed that the maximal eccentric range of hip flexion/extension of 128.6° for the young female group (P < 0.05) was compared with that of 158.8° for the elder female group. Thus, the elder female undergoes more hip flexion/extension angles than the young female in the posture of squatting. The mean range of motion (ROM) of knee flexion/extension was 140.2° for the young female group and 138.7° (significant level P > 0.05) for the elder female group. The mean ROM of ankle flexion/extension was 47.90° for the young female group and 31.9° (P > 0.05) for the elder female group. The ROMs obtained in the experiment during squatting were greater than the reported ones achieved after joint arthroplasty. These data may be invaluable in providing designers of lower limb prosthesis with basic mechanical parameters, and assessing the effect of kinematics of low limb on rehabilitation for the Chinese population.
In nanocrystalline (nc) metals, it is still not clear how local grain boundary (GB) structures accommodate GB migration at atomic scales and what dominates the motion of atoms at the inherently unstable GB front. Here, we report the adjustment of the local GB structures at atomic scales during self-driven GB migration, simultaneously involving GB dissociation, partial dislocation emission from GB, and faceting/defaceting in the nc Cu. Furthermore, we reveal that the fundamental of GB migration ability is closely related to the local structure, i.e. the GB segment consisting of “hybrid” structural units and delocalized GB dislocations is relatively unstable.
Legionnaires’ disease (LD) is a globally distributed systemic infectious disease. The burden of LD in many regions is still unclear, especially in Asian countries including China. A survey of Legionella infection using real-time PCR and nested sequence-based typing (SBT) was performed in two hospitals in Shanghai, China. A total of 265 bronchoalveolar lavage fluid (BALF) specimens were collected from hospital A between January 2012 and December 2013, and 359 sputum specimens were collected from hospital B throughout 2012. A total of 71 specimens were positive for Legionella according to real-time PCR focusing on the 5S rRNA gene. Seventy of these specimens were identified as Legionella pneumophila as a result of real-time PCR amplification of the dotA gene. Results of nested SBT revealed high genetic polymorphism in these L. pneumophila and ST1 was the predominant sequence type. These data revealed that the burden of LD in China is much greater than that recognized previously, and real-time PCR may be a suitable monitoring technology for LD in large sample surveys in regions lacking the economic and technical resources to perform other methods, such as urinary antigen tests and culture methods.
Suicide in China has declined since the 1990s. However, there has been limited investigation of the potential spatiotemporal variation and social determinants of suicide during subsequent periods.
Annual suicide counts from 2006 to 2012 stratified by county, 5-year age group (⩾15 years) and gender were obtained from the Chinese Disease Surveillance Points system. Trends and geographic differentials were examined using multilevel negative binomial regression models to explore spatiotemporal variation in suicide, and the role of key sociodemographic factors associated with suicide.
The suicide rate (per 100 000) in China decreased from 14.7 to 9.1, 2006–2012. Rates of suicide were higher in males than females and increased substantially with age. Suicide rates were higher in rural areas compared with urban areas; however, urban–rural disparities reduced over time with a faster decline for rural areas. Within both urban and rural areas, higher rates of suicide were evident in areas with lower socio-economic circumstances (SEC) [rate ratio (RR) 1.85, 95% confidence interval (CI) 1.31–2.62]. Suicide rates varied more than twofold (median RR 2.06) across counties, and were highest in central and southwest regions of China. A high proportion of the divorced population, especially for younger females, was associated with lower suicide rates (RR 0.60, 95% CI 0.46–0.79).
Geographic variations for suicide should be taken into account in policy making, particularly for older males living in rural areas and urban areas with low SEC. Measures to reduce disparities in socio-economic level and alleviate family relation stress are current priorities.
The soft scales (Hemiptera: Coccoidea: Coccidae) are a group of sap-sucking plant parasites, many of which are notorious agricultural pests. The quarantine and economic importance of soft scales necessitates rapid and reliable identification of these taxa. Nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene (barcoding region) and 28S rDNA were generated from 340 individuals of 36 common soft scales in China. Distance-based [(best match, Automated Barcode Gap Discovery (ABGD)], tree-based (neighbor-joining, Bayesian inference), Klee diagrams, and general mixed Yule coalescent (GMYC) models were used to evaluate barcoding success rates in the data set. Best match showed that COI and 28S sequences could provide 100 and 95.52% correct identification, respectively. The average interspecific divergences were 19.81% for COI data and 20.38% for 28S data, and mean intraspecific divergences were 0.56 and 0.07%, respectively. For COI data, multiple methods (ABGD, Klee, and tree-based methods) resulted in general congruence with morphological identifications. However, GMYC analysis tended to provide more molecular operational taxonomic units (MOTUs). Twelve MOTUs derived from five morphospecies (Rhodococcus sariuoni, Pulvinaria vitis, Pulvinaria aurantii, Parasaissetia nigra, and Ceroplastes rubens) were observed using the GMYC approach. In addition, tree-based methods showed that 28S sequences could be used for species-level identification (except for Ceroplastes ceriferus – Ceroplastes pseudoceriferus), even with low genetic variation (<1%). This report demonstrates the robustness of DNA barcoding for species discrimination of soft scales with two molecular markers (COI and 28S) and provides a reliable barcode library and rapid diagnostic tool for common soft scales in China.