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.
Cysticercosis caused by the metacestode larval stage of Taenia hydatigena formerly referred to as Cysticercus tenuicollis is a disease of veterinary importance that constitutes a significant threat to livestock production worldwide, especially in endemic regions due to condemnation of visceral organs and mortality rate of infected young animals. While the genetic diversity among parasites is found to be potentially useful in many areas of research including molecular diagnostics, epidemiology and control, that of T. hydatigena across the globe remains poorly understood. In this study, analysis of the mitochondrial DNA (mtDNA) of adult worms and larval stages of T. hydatigena isolated from dogs, sheep and a wild boar in China showed that the population structure consists of two major haplogroups with very high nucleotide substitutions involving synonymous and non-synonymous changes. Compared with other cestodes such as Echinococcus spp., the genetic variation observed between the haplogroups is sufficient for the assignment of major haplotype or genotype division as both groups showed a total of 166 point-mutation differences between the 12 mitochondrial protein-coding gene sequences. Preliminary analysis of a nuclear protein-coding gene (pepck) did not reveal any peculiar changes between both groups which suggests that these variants may only differ in their mitochondrial makeup.
Distinguished by a marked combination of high strength and high fracture toughness, 18Ni-300 maraging steel (MS) is widely used for intricate tool and die applications. MS is also amenable to the powder bed fusion additive manufacturing process, providing unique opportunities to make small features and incorporate cooling channels in molds. In this study, tensile test samples were fabricated using selective laser melting to investigate the effects of built height and orientations on the evolution of the microstructure and the mechanical properties of the samples. The microstructure of the as-fabricated samples consists of the primary α-martensite phase and fine cellular microstructure (~0.66–0.83 μm) with the retained austenite γ-phase aggregated at the boundaries of the cells, resulting in an enhanced mechanical performance compared with traditional counterparts under the same condition (without post-heat treatments). Random grain orientations with weak textures are revealed in all samples. The XY-built samples display better tensile performance when compared to the Z-built samples due to the fine grain sizes and the retained γ phase. The bottom of the Z-built sample exhibits a higher hardness than other parts of the sample, which could be attributed to its finer cellular structure.
Major depressive disorder is characterized by a high risk of relapse. We aimed to compare the prophylactic effects of different antidepressant medicines (ADMs).
PubMed, Cochrane Central Register of Controlled Trials, Embase and the Web of Science were searched on 4 July 2019. A pooled analysis of parametric survival curves was performed using a Bayesian framework. The main outcomes were hazard ratios (HRs), relapse-free survival and mean relapse-free months.
Forty randomized controlled trials were included. The 1-year relapse-free survival for ADM (76%) was significantly better than that for placebo (56%). Most of the relapse difference (86.5%) occurred in the first 6 months. Most HRs were not constant over time. Proof of benefit after 6 months of follow-up was not established partially because of small differences between the drug and placebo after 6 months. Almost all studies used an ‘enriched’ randomized discontinuation design, which may explain the high relapse rates in the first 6 months after randomization.
The superiority of ADM v. placebo was mainly attributed to the difference in relapse rates that occurred in the first 6 months. Our analysis provided evidence that the prophylactic efficacy was not constant over time. A beneficial effect was observed, but the prevention of new episodes after 6 months was questionable. These findings may have implications for clinical practice.
The objective of the present study was to elucidate whether resveratrol could facilitate the survival of boar sperm during liquid preservation and fast cooling processes. Boar semen were diluted with Modena extender containing different concentrations of resveratrol. Sperm motility was evaluated by visual estimation. Membrane integrity, acrosome integrity and mitochondrial membrane potentials were measured by SYBR-14/PI, FITC-PNA and JC-1 staining, respectively. Moreover, the levels of reactive oxygen species (ROS), malonaldehyde (MDA) and total antioxidant capacity (T-AOC) were measured using commercial assay kits. B-cell lymphoma protein-2 (BCL2) content was determined by western blotting. During liquid preservation at 17oC, the addition of 50 μM resveratrol to the Modena extender significantly improved sperm motility, membrane integrity, acrosome integrity, and sperm mitochondrial membrane potentials. Similar results were also observed in the 150 μM resveratrol group during the fast cooling process. Furthermore, addition of resveratrol led to a decrease of ROS and MDA, and an increase in the content of T-AOC and BCL2. These observations suggest that addition of resveratrol to Modena extender protects boar sperm against oxidative stress. The optimal concentrations of resveratrol are 50 μM and 150 μM during liquid preservation and fast cooling process, respectively.
The present study investigated the effects of condensed tannins (CT) on intestinal immune function in on-growing grass carp (Ctenopharyngodon idella). A total of 540 healthy grass carp were fed six diets containing different levels of CT (0, 10·00, 20·00, 30·00, 40·00 and 50·00 g/kg diet) for 70 d and then challenged with Aeromonas hydrophila for 14 d. The results showed that, compared with the control group, dietary CT (1) induced intestinal histopathological lesions and aggravated enteritis; (2) decreased lysozyme and acid phosphatase activities, complement 3 (C3), C4 and IgM contents and down-regulated the Hepcidin, liver-expressed antimicrobial peptide (LEAP)-2A, LEAP-2B, Mucin2 and β-defensin-1 mRNA levels in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI) (P < 0·05); (3) down-regulated the mRNA levels of anti-inflammatory cytokines transforming growth factor (TGF)-β1, TGF-β2 (not in MI and DI), IL-4/13A (not IL-4/13B), IL-10 and IL-11 partly correlated with target of rapamycin (TOR) signalling; and (4) up-regulated the mRNA levels of pro-inflammatory cytokines interferon-γ2, IL-1β, IL-6, IL-8 (not in PI), IL-12p35, IL-12p40, IL-15 and IL-17D partly related to NF-κB signalling in the intestine of on-growing grass carp. Overall, the results indicated that CT could impair the intestinal immune function, and its potential regulation mechanisms were partly associated with the TOR and NF-κB signalling pathways. Finally, based on the percentage weight gain and enteritis morbidity, the maximum allowable levels of CT for on-growing grass carp (232·22–890·11 g) were estimated to be 18·6 and 17·4 g/kg diet, respectively.
The objectives of this study were to investigate the primary diagnoses and outcomes of emergency department visits in older people with dementia and to compare these parameters with those in older adults without dementia.
Design and Setting:
This hospital-based retrospective study retrieved patient records from a hospital research database, which included the outpatient and inpatient claims of two hospitals.
The patient records were retrieved from the two hospitals in an urban setting. The inclusion criteria were all patients aged 65 and older who had attended the two hospitals as an outpatient or inpatient between January 1, 2009, and December 31, 2016. Patients with dementia were identified to have at least three reports of diagnostic codes, either during outpatient visits, during emergency department visits, or in hospitalized database records. The other patients were categorized as patients without dementia.
The primary diagnosis during the emergency department visit, cost of emergency department treatment, cost of hospital admission, length of hospital stay, and diagnosis of death were collected.
A total of 149,203 outpatients and inpatients aged 65 and older who were admitted to the two hospitals were retrieved. The rate of emergency department visits in patients with dementia (23.2%) was lower than that in those without dementia (48.6%). The most frequent primary reason for emergency department visits and the main cause of patient death was pneumonia. Patients with dementia in the emergency department had higher hospital admission rates and longer hospital stays; however, the cost of treatment did not show a significant difference between the two groups.
Future large and prospective studies should explore the severity of disease in older people with dementia and compare results with older adults without dementia in the emergency department.
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.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
In this study, the petrology, zircon U–Pb ages, Lu–Hf isotopic compositions, whole-rock geochemistry and Sr–Nd isotopes for newly recognized low-Mg and high-Mg adakitic rocks from the North Altun orogenic belt were determined. The results will provide important insights for understanding the continuities of the North Qilian and North Altun orogenic belts during early Palaeozoic time. The low-Mg adakitic granitoids (445 to 439 Ma) are characterized by high SiO2 (69–70 wt %), low Mg no. (43–48) and low Cr and Ni contents. In contrast, the high-Mg adakitic granitoids (425 to 422 Ma) have relatively lower SiO2 (65–67 wt %), higher Mg no. (60–62) and higher Cr and Ni contents. The low-Mg adakitic rocks have high initial 87Sr/86Sr ratios (0.7073–0.7084), negative εNd(t) (−1.9 to −4.0) and εHf(t) values (−6.8 to −2.0), and old zircon Hf model ages (1.4–1.7 Ga). In contrast, the high-Mg adakitic rocks show lower initial 87Sr/86Sr ratios (0.7044–0.7057), higher εNd(t) (−0.7 to 3.1) and positive εHf(t) values (2.0 to 6.9), with younger zircon Hf model ages (0.9–1.2 Ga). These results suggest that the low-Mg adakitic rocks were probably generated by the partial melting of thickened crust, whereas the high-Mg adakitic rocks were derived from the anatexis of delaminated lower crust, which subsequently interacted with mantle magma upon ascent. The data obtained in this study provide significant information about the geological and tectonic processes after the closure of the Altun Ocean. The continent–continent collision and thickening probably occurred during 450–440 Ma with the formation of low-Mg adakitic rocks, and the transition of the tectonic regime from compression to extension probably occurred at 425–422 Ma with the formation of high-Mg adakitic rocks. The geochemical, geochronological and petrogenetic similarities between the North Altun and North Qilian adakitic rocks suggest that these two orogenic belts were subjected to similar tectonomagmatic processes during early Palaeozoic times.
The present study investigated the effects of dietary vitamin A on immune function in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI) of young grass carp (Ctenopharyngodon idella). Fish were fed graded levels of dietary vitamin A for 10 weeks, and then a challenge test using an injection of Aeromonas hydrophila was conducted for 14 d. The results showed that, compared with the optimum vitamin A level, vitamin A deficiency significantly decreased fish growth performance, increased enteritis morbidity, decreased intestinal innate humoral immune response and aggravated intestinal inflammation. However, liver-expressed antimicrobial peptide 2A/B mRNA in the DI and IL-6, IL-17D, IL-10, transforming growth factor (TGF)-β1 and TGF-β2 mRNA in the PI were not affected by vitamin A levels. Meanwhile, vitamin A deficiency disturbed inflammatory cytokines in the PI, MI and DI, which might be partly linked to p38 mitogen-activated protein kinase (p38MAPK) signalling and NF-κB canonical signalling pathway (IκB kinase β (IKKβ), IKKγ, inhibitor of κBα, NF-κB p65 and c-Rel) rather than NF-κB non-canonical signalling pathway (NF-κB p52 and IKKα). However, the signalling molecules NF-κB p65 and p38MAPK did not participate in regulating cytokines in the PI. These results suggested that vitamin A deficiency decreased fish growth and impaired intestinal immune function, and that different immune responses in the PI, MI and DI were mediated partly by NF-κB canonical signalling and p38MAPK signalling pathways. On the basis of percentage of weight gain, to protect fish against enteritis morbidity and acid phosphatase activity, the optimum dietary vitamin A levels were estimated to be 0·664, 0·707 and 0·722 mg /kg, respectively.
This study was conducted to determine the effects of l-carnitine (LC), as an antioxidant, in preventing spermatozoa damage during the freezing–thawing process in both astheno- and normozoospermic human semen samples. Seventy semen samples (37 asthenozoospermic and 33 normozoospermic) were involved in this study. Cryopreservation medium supplemented with 1.0 g/l LC was mixed with semen at a ratio of 1:1 (v/v). Controls were cryopreserved with freezing medium only. Assessment of motility, viability (VIA), mitochondrial membrane potential (MMP) and DNA fragmentation index (DFI) were performed on aliquots of fresh semen, frozen–thawed control and frozen–thawed LC treated samples. Supplementation of the cryopreservation medium with LC induced a significant improvement in post-thaw sperm parameters in both the asthenozoospermic and normozoospermic semen samples, compared with those of the control, regarding sperm fast forward motility, forward motility, total motility and VIA. LC showed better protective effects towards asthenozoospermia for DFI (F = 115.85, P < 0.01) and VIA (F = 67.14, P < 0.01) than did normozoospermic semen samples. We conclude that supplementation with LC prior to the cryopreservation process reduced spermatozoa cryodamage in both asthenozoospermic and normozoospermic semen samples. LC had better protective effects for asthenozoospermic human semen samples. Future research should focus on the molecular mechanism for and the different protective effects of LC between asthenozoospermic and normozoospermic semen samples during cryopreservation.
Potassium dihydrogen phosphate (KDP) single crystals are the only nonlinear crystals currently used for electro-optic switches and frequency converters in inertial confinement fusion research, due to their large dimension and exclusive physical properties. Based on the traditional solution-growth process, large bulk KDP crystals, usually with sizes up to 600
so as to make a frequency doubler for the facility requirement loading highly flux of power laser, can be grown in standard Holden-type crystallizers, without spontaneous nucleation and visible defects, one to two orders of magnitude faster than by conventional methods. Pure water and KDP raw material with a few ion impurities such as Fe, Cr, and Al (less than 0.1 ppm) were used. The rapid-growth method includes extreme conditions such as temperature range from 60 to 35
C, overcooling up to 5
C, growth rates exceeding 10 mm/day, and crystal size up to 600 mm. The optical parameters of KDP crystals were determined. The optical properties of crystals determined indicate that they are of favorable quality for application in the facility.
The discovery of c. 1.77 Ga A-type granite in the Tarim Craton (TC) provides the first evidence that supports an extensional event related to fragmentation of the Columbia supercontinent in the late Palaeoproterozoic. We present laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U–Pb ages, Lu–Hf isotopic data and the whole-rock geochemical and Nd isotopic data of A-type granites in the Dunhuang area in the SE Tarim Craton. Zircon U–Pb dating for three granite samples indicate that they were emplaced at c. 1.77 Ga. Zircons from these granites have εHf(t) values ranging from –5.9 to 8.7, corresponding to two-stage model ages of 1.9–2.7 Ga. These granites exhibit the following petrological geochemical characteristics that are typical of A-type granite: (a) high content of SiO2 and alkalis (i.e. high K2O + Na2O with K2O/Na2O > 1), enrichment of high-field-strength elements (HFSE) and rare Earth elements (REE) (except for Eu) and extreme depletion of Ba, Sr, P, Ti and Eu; (b) 10000×Ga/Al ratios in the Dunhuang granites of 3.5–4.4, with an average value of 3.79 which is similar to the global average of 3.75 for A-type granites; (c) the presence of characteristic minerals such as amphibole, sphene and perthite; and (d) zirconium saturation temperature results indicate that the Dunhuang granites have high initial magmatic temperatures in the range 887–950°C, similar to those of typical of A-type granites. Whole-rock εNd(t) values range from –2.5 to –6.2 and TDM model ages from 2.3 to 2.7 Ga. Nd–Hf isotopic and whole-rock geochemical data indicate that these granites were most likely derived from the late Archean crustal source in a post-collisional/post-orogenic extensional tectonic environment. The late Palaeoproterozoic A-type granites in the TC could be correlated with those of the North China Craton (NCC), India and the Canadian Shield, thus demonstrating extensional tectonics and break-up of the Columbia supercontinent.
Background: Although accumulating research demonstrates the association between attentional bias and social anxiety, the bias for positive stimuli has so far not been adequately studied. Aims: The aim is to investigate the time-course of attentional bias for positive social words in participants with high and low social anxiety. Method: In a modified dot-probe task, word-pairs of neutral and positive social words were randomly presented for 100, 500, and 1250 milliseconds in a nonclinical sample of students to test their attentional bias. Results: Non-significant interaction of Group × Exposure Duration was found. However, there was a significant main effect of group, with significantly different response latencies between the high social anxiety (HSA) and low social anxiety (LSA) groups in the 100 ms condition, without for 500 or 1250 ms. With respect to attentional bias, the LSA group showed enhanced preferential attention for positive social words to which the HSA group showed avoidance in the 100 ms condition. In the 500 ms condition, preferential attention to positive social words was at trend in the LSA group, relative to the HSA group. Neither group showed attentional bias in the 1250 ms condition. Conclusions: These findings extend recent research about the attention training program and add to the empirical literature suggesting that the initial avoidance of positive stimuli may contribute to maintaining social anxiety.
Probiotics are normal inhabitants of the gastrointestinal tract of man and are widely considered to exert a number of beneficial effects in many diseases. But the mechanism by which they modulate the immune system is poorly understood. The present study was planned to explore the anti-allergic effect of Lactobacillus gasseri on a mouse model of allergic asthma. Dermatophoides pteronyssinus (Der p) sensitised and challenged BALB/c mice were orally administered via oral administration with three different doses of L. gasseri (low, 1 × 106 colony-forming units (CFU); medium, 2 × 106 CFU; high, 4 × 106 CFU), in 700 μl of PBS daily, starting from 2 weeks before Der p sensitisation for 4 weeks. After the allergen challenge, airway responsiveness to methacholine, influx of inflammatory cells to the lung, and cytokine levels in bronchoalveolar lavage (BAL) fluids and splenocytes culture were assessed. Our results showed that oral administration of a high dose of L. gasseri (4 × 106 CFU) decreased airway responsiveness to methacholine, attenuated the influx of inflammatory cells to the airways and reduced the levels of TNF-α, thymus and activation-regulated chemokine (TARC) and IL-17A in BAL fluids of Der p-sensitised and -challenged mice. Moreover, L. gasseri decreased IL-17A production in transforming growth factor-α and IL-6 stimulated splenocytes and cell numbers of IL-17 producing alveolar macrophages in L. gasseri-treated mice as compared to non-treated, Der p-sensitised and -challenged mice. In conclusion, oral administration with L. gasseri can attenuate major characteristics of allergen-induced airway inflammation and IL-17 pro-inflammatory immune response in a mouse model of allergic asthma, which may have clinical implication in the preventive or therapeutic potential in allergic asthma.
Seven isoenergetic semi-purified test diets containing graded levels of protein ranging from 20 to 50% were formulated using fish meal and casein as the protein sources. Test diets were fed to triplicate groups of Barbodes caldwelli juveniles with initial body weights of 1.26±0.02 g for eight weeks. The results indicated no significant effect of dietary protein levels on survival rate, relative weight of the viscera and relative weight of the liver in the juvenile fish. The weight gain and specific growth rate of the fish were found to be greater as dietary protein levels increased from 20 to 35%, but were not affected significantly as dietary protein level increased from 35 to 50%. Feed efficiencies did not differ significantly when fish were fed diets with protein levels from 30 to 50%, but were significantly higher than those of fish fed diets with protein levels of 20 and 25%. The protein efficiency ratio (PER) was negatively correlated with diet protein level (x) (PER=3.006−0.03251x, R=0.9366). There was no significant effect of dietary protein levels on carcass moisture, crude protein and ash. However, carcass lipid levels (L) decreased with an increase in dietary protein level (x) (L=8.2169−0.0458x, R=0.8551). There was no significant variation in hepatopancreas protease activity among the tests. Intestine protease activity and hepatopancreas amylase activity were increased to some extent, and then decreased as dietary protein levels continued to rise. The intestine amylase activity (IAA) of the juveniles was negatively correlated with dietary protein level (x) (IAA=84.625−0.9147x, R=0.8463). It was estimated that the suitable protein level for the B. caldwelli juvenile is 34% (the broken-line model was used to regress the relationship of the weight gain of the juvenile and dietary protein level).
The statistical analysis of heating effect and the cross-correlation analysis of both electron temperature and loop voltage have been done during electron cyclotron resonance heating (ECRH). The behavior of runaway electrons in the flat-top phase during ECRH are analyzed using experimental data. It is shown that the runaway population is indeed suppressed or even quenched when the toroidal electric field ET is reduced below the threshold electric field Eth by high-power and long-duration ECRH. The physical mechanism of runaway suppression is explored by the resonant interaction between the electron cyclotron waves and the energetic runaway electrons.
The basal Cambrian marks the beginning of an important chapter in the history of life. However, most paleontological work on the basal Cambrian has been focused on skeletal animal fossils, and our knowledge about the primary producers—cyanobacteria and eukaryotic phytoplankton (e.g., acritarchs)—is limited. In this research, we have investigated basal Cambrian acritarchs, coccoidal microfossils, and cyanobacteria preserved in phosphorites and cherts of the Yanjiahe Formation in the Yangtze Gorges area (South China) and the Yurtus Formation in the Aksu area (Tarim Block, northwestern China). Our study confirms the occurrence in these two formations of small acanthomorphic acritarchs characteristic of the basal Cambrian Asteridium–Comasphaeridium–Heliosphaeridium (ACH) assemblage. These acritarchs include abundant Heliosphaeridium ampliatimi (Wang, 1985) Yao et al., 2005, common Yurtusia uniformis n. gen. and n. sp., and rare Comasphaeridium annulare (Wang, 1985) Yao et al., 2005. In addition, these basal Cambrian successions also contain the clustered coccoidal microfossil Archaeophycus yunnanensis (Song in Luo et al., 1982) n. comb., several filamentous cyanobacteria [Cyanonema majus n. sp., Oscillatoriopsis longa Timofeev and Hermann, 1979, and Siphonophycus robustum (Schopf, 1968) Knoll et al., 1991], and the tabulate tubular microfossil Megathrix longus L. Yin, 1987a, n. emend. Some of these taxa (e.g., H. ampliatum, C. annulare, and M. longus) have a wide geographic distribution but occur exclusively in basal Cambrian successions, supporting their biostratigraphic importance. Comparison between the stratigraphic occurrences of microfossils reported here and skeletal animal fossils published by others suggests that animals and phytoplankton radiated in tandem during the Cambrian explosion.