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To meet the demands of laser-ion acceleration at a high repetition rate, we have developed a comprehensive diagnostic system for real-time and in situ monitoring of liquid sheet targets (LSTs). The spatially resolved rapid characterizations of an LST’s thickness, flatness, tilt angle and position are fulfilled by different subsystems with high accuracy. With the help of the diagnostic system, we reveal the dependence of thickness distribution on collision parameters and report the 238-nm liquid sheet generated by the collision of two liquid jets. Control methods for the flatness and tilt angle of LSTs have also been provided, which are essential for applications of laser-driven ion acceleration and others.
Here, we report the generation of MeV alpha-particles from H-11B fusion initiated by laser-accelerated boron ions. Boron ions with maximum energy of 6 MeV and fluence of 109/MeV/sr@5 MeV were generated from 60 nm-thick self-supporting boron nanofoils irradiated by 1 J femtosecond pulses at an intensity of 1019 W/cm2. By bombarding secondary hydrogenous targets with the boron ions, 3 × 105/sr alpha-particles from H-11B fusion were registered, which is consistent with the theoretical yield calculated from the measured boron energy spectra. Our results demonstrated an alternative way toward ultrashort MeV alpha-particle sources employing compact femtosecond lasers. The ion acceleration and product measurement scheme are referential for the studies on the ion stopping power and cross section of the H-11B reaction in solid or plasma.
Post-acceleration of protons in helical coil targets driven by intense, ultrashort laser pulses can enhance ion energy by utilizing the transient current from the targets’ self-discharge. The acceleration length of protons can exceed a few millimeters, and the acceleration gradient is of the order of GeV/m. How to ensure the synchronization between the accelerating electric field and the protons is a crucial problem for efficient post-acceleration. In this paper, we study how the electric field mismatch induced by current dispersion affects the synchronous acceleration of protons. We propose a scheme using a two-stage helical coil to control the current dispersion. With optimized parameters, the energy gain of protons is increased by four times. Proton energy is expected to reach 45 MeV using a hundreds-of-terawatts laser, or more than 100 MeV using a petawatt laser, by controlling the current dispersion.
T long-term effects of cognitive therapy and behavior therapy (CTBT) for menopausal symptoms are unknown, and whether the effects are different between natural menopause and treatment-induced menopause are currently unclear. Therefore, we sought to conduct an accurate estimate of the efficacy of CTBT for menopausal symptoms.
Methods
We conducted searches of Cochrane Library, EMBASE, PsycINFO, PubMed, and Web of Science databases for studies from 1 January 1977 to 1 November 2021. Randomized controlled trials (RCTs) comparing intervention groups to control groups for menopausal symptoms were included. Hedge's g was used as the standardized between-group effect size with a random-effects model.
Results
We included 14 RCTs comprising 1618 patients with a mean sample size of 116. CTBT significantly outperformed control groups in terms of reducing hot flushes [g = 0.39, 95% confidence interval (CI) 0.23–0.55, I2 = 45], night sweats, depression (g = 0.50, 95% CI 0.34–0.66, I2 = 51), anxiety (g = 0.38, 95% CI 0.23–0.54, I2 = 49), fatigue, and quality of life. Egger's test indicated no publication bias.
Conclusions
CTBT is an effective psychological treatment for menopausal symptoms, with predominantly small to moderate effects. The efficacy is sustained long-term, although it declines somewhat over time. The efficacy was stronger for natural menopause symptoms, such as vasomotor symptoms, than for treatment-induced menopause symptoms. These findings provide support for treatment guidelines recommending CTBT as a treatment option for menopausal symptoms.
Carbon nanotube foams (CNFs) have been successfully used as near-critical-density targets in the laser-driven acceleration of high-energy ions and electrons. Here we report the recent advances in the fabrication technique of such targets. With the further developed floating catalyst chemical vapor deposition (FCCVD) method, large-area ($>25\kern0.5em {\mathrm{cm}}^2$) and highly uniform CNFs are successfully deposited on nanometer-thin metal or plastic foils as double-layer targets. The density and thickness of the CNF can be controlled in the range of $1{-}13\kern0.5em \mathrm{mg}/{\mathrm{cm}}^3$ and $10{-}200\kern0.5em \mu \mathrm{m}$, respectively, by varying the synthesis parameters. The dependence of the target properties on the synthesis parameters and the details of the target characterization methods are presented for the first time.
Microtubule-severing protein (MTSP) is critical for the survival of both mitotic and postmitotic cells. However, the study of MTSP during meiosis of mammalian oocytes has not been reported. We found that spastin, a member of the MTSP family, was highly expressed in oocytes and aggregated in spindle microtubules. After knocking down spastin by specific siRNA, the spindle microtubule density of meiotic oocytes decreased significantly. When the oocytes were cultured in vitro, the oocytes lacking spastin showed an obvious maturation disorder. Considering the microtubule-severing activity of spastin, we speculate that spastin on spindles may increase the number of microtubule broken ends by severing the microtubules, therefore playing a nucleating role, promoting spindle assembly and ensuring normal meiosis. In addition, we found the colocalization and interaction of collapsin response mediator protein 5 (CRMP5) and spastin in oocytes. CRMP5 can provide structural support and promote microtubule aggregation, creating transportation routes, and can interact with spastin in the microtubule activity of nerve cells (30). Knocking down CRMP5 may lead to spindle abnormalities and developmental disorders in oocytes. Overexpression of spastin may reverse the abnormal phenotype caused by the deletion of CRMP5. In summary, our data support a model in which the interaction between spastin and CRMP5 promotes the assembly of spindle microtubules in oocytes by controlling microtubule dynamics, therefore ensuring normal meiosis.
Single-shot laser-induced damage threshold (LIDT) measurements of multi-type free-standing ultrathin foils were performed in a vacuum environment for 800 nm laser pulses with durations τ ranging from 50 fs to 200 ps. The results show that the laser damage threshold fluences (DTFs) of the ultrathin foils are significantly lower than those of corresponding bulk materials. Wide band gap dielectric targets such as SiN and formvar have larger DTFs than semiconductive and conductive targets by 1–3 orders of magnitude depending on the pulse duration. The damage mechanisms for different types of targets are studied. Based on the measurement, the constrain of the LIDTs on the laser contrast is discussed.
The factors associated with suicidal ideation among adolescents have been extensively characterised, but the mechanisms underlying the complexities of the relationship between experiences of childhood trauma and suicidal ideation have been less studied. This study examined the direct effect of childhood trauma on suicidal ideation on the one hand and whether school bullying victimisation and Internet addiction mediate the association between childhood trauma and suicidal ideation on the other hand.
Methods
This school-based mental health survey was carried out in Qinghai Province in Northwest China in December 2019. We employed standardised questionnaires to collect sociodemographic and target mental health outcomes. Hierarchical multiple logistic regression and structural equation modelling were performed for the data analyses.
Results
This study included 5864 university students. The prevalence of lifetime suicidal ideation and Internet addiction were 34.7% and 21.4%, respectively. Overall, 16.4% and 11.4% of participants reported experiences of childhood trauma and school bullying victimisation, respectively. There were direct effects of childhood trauma, school bullying victimisation and Internet addiction on suicidal ideation. The total effect of childhood trauma on suicidal ideation was 0.201 (p < 0.001). School bullying victimisation and Internet addiction mediated the relationship between childhood trauma and suicidal ideation. Internet addiction played a mediating role between school bullying and suicidal ideation.
Conclusions
Childhood trauma had both direct and indirect effects on suicidal ideation; these effects were mediated by school bullying victimisation and Internet addiction in Chinese university students. Elucidating these relationships will therefore be useful in developing and implementing more targeted interventions and strategies to improve the mental well-being of Chinese university students.
As part of our ongoing research on Peltigera, we recognize a morphologically and phylogenetically distinct new species, Peltigera shennongjiana L. F. Han & S. Y. Guo, from the Shennongjia region of Central China. It is distinguished from other members of the P. canina-group by the presence of abundant phyllidia and flat, branched lobules along the margin or laminal cracks, short lobes, and a pruinose, usually greyish upper surface. The various populations sampled share identical ITS nr DNA sequences, of which the ITS2 regions are characterized by a unique secondary structure. Furthermore, we provide a detailed comparison of the characteristics of P. shennongjiana with morphologically similar species and a key to Peltigera species reported from China.
Many shorebird populations are in decline along the East Asian-Australasian Flyway. The rapid loss of coastal wetlands in the Yellow Sea, which provide critical stop-over sites during migration, is believed to be the cause of the alarming trends. The Yalu Jiang coastal wetland, a protected area in the north Yellow Sea, supports the largest known migratory staging populations of Bar-tailed Godwits Limosa lapponica (menzbieri and baueri subspecies) and Great Knots Calidris tenuirostris. Monitoring of the macrozoobenthos food for these shorebirds from 2011 to 2016 showed declines of over 99% in the densities of the bivalve Potamocorbula laevis, the major food here for both Bar-tailed Godwits and Great Knots. The loss of the bivalve might be caused by any combination of, but not limited to: (1) change in hydrological conditions and sediment composition due to nearby port construction, (2) run-off of agrochemicals from the extensive shoreline sea cucumber farms, and (3) parasitic infection. Surprisingly, the numbers of birds using the Yalu Jiang coastal wetland remained stable during the study period, except for the subspecies of Bar-tailed Godwit L. l. menzbieri, which exhibited a 91% decline in peak numbers. The lack of an overall decline in the number of bird days in Great Knots and in the peak numbers of L. l. baueri, also given the published simultaneous decreases in their annual survival, implies a lack of alternative habitats that birds could relocate to. This study highlights that food declines at staging sites could be an overlooked but important factor causing population declines of shorebirds along the Flyway. Maintaining the quality of protected staging sites is as important in shorebird conservation as is the safeguarding of staging sites from land claim. Meanwhile, it calls for immediate action to restore the food base for these beleaguered migrant shorebirds at Yalu Jiang coastal wetland.
To evaluate the effects of different anthropogenic activities on zooplankton and the pelagic ecosystem, we conducted seasonal cruises in 2010 to assess spatial heterogeneity among the mesozooplankton communities of Xiangshan Bay, a subtropical semi-enclosed bay in China. The evaluation included five different areas: a kelp farm, an oyster farm, a fish farm, the thermal discharge area of a power plant, and an artificial reef, and we aimed to identify whether anthropogenic activities dominated spatial variation in the mesozooplankton communities. The results demonstrated clear spatial heterogeneity among the mesozooplankton communities of the studied areas, dominantly driven by natural hydrographic properties, except in the area near the thermal discharge outlet of the power station. In the outlet area, thermal shock caused by the discharge influenced the mesozooplankton community by decreasing abundance and biomass throughout the four seasons, even causing a shift in the dominant species near the outlet during summer from Acartia pacifica to eurythermal and warm water taxa. Unique features of the mesozooplankton community in the oyster farm may be due to the combined effects of oyster culture and the natural environment in the branch harbour. However, kelp and fish culture, and the construction of an artificial reef did not exert any obvious influence on the mesozooplankton communities up to 2010, probably because of the small scale of the aquaculture and a time lag in the rehabilitation effects of the artificial reef. Thus, our results suggested that the dominant factors influencing spatial variations of mesozooplankton communities in Xiangshan Bay were still the natural hydrographic properties, but the thermal discharge was an anthropogenic activity that changed the pelagic ecosystem, and should be supervised.
Reports arose from major Chinese wheat production regions that flixweed was not controlled by tribenuron after the herbicide was continuously used for several years. Flixweed seeds were collected from wheat fields that had been treated with tribenuron repeatedly over 3 to 15 yr or from road sides and remote hills that had never received tribenuron in Jiangsu, Hebei, Shanxi, Sichuan, Shandong, Shaanxi, and Henan provinces, and Tianjin and Beijing metropolises in China. The response of various biotypes to tribenuron was determined by whole plant experiments in the greenhouse. The experiments demonstrated that 11 of 32 flixweed biotypes were susceptible to tribenuron. The remaining 21 biotypes expressed moderate to high levels of tribenuron resistance with resistance indices ranging from 4 to > 1,500. DNA sequence analysis of acetolactate synthase (ALS) genes of selected biotypes 6, 7, 27, and 29 revealed a point mutation at position 197 of the ALS gene, as numbered relative to the protein sequence of Arabidopsis, where proline was substituted by leucine in biotype 7 and by threonine in biotype 29. These mutations are known to confer resistance to ALS-inhibiting herbicides and are responsible for the high resistance of these biotypes to tribenuron. The results also indicate that tribenuron resistance in flixweed is widespread in China and management programs to control these resistant populations are warranted.
Hepatocellular carcinoma (HCC) is a primary liver malignancy that mainly occurs in patients with chronic liver disease and cirrhosis. Risk factors for HCC include hepatitis B virus (HBV) infection. However, the specific role of HBV infection in HCC development is not yet completely understood. In order to reveal the effects of HBV on HCC, we compare the genes of HCC patients infected with HBV with those who are not infected.
Methods:
We encoded the genes of these two types of HCC in databases using enrichment scores of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway terms. A random forest algorithm was employed in order to distinguish these two types in the classifier, and a series of feature selection approaches was used in order to select their optimal features. Novel HBV-associated and -non-associated HCC genes were predicted, respectively, based on their optimal features in the classifier. A shortest-path algorithm was also employed in order to find all of the shortest-paths genes connecting the known related genes.
Results:
A total of 54 different features between HBV-associated and -non-associated HCC genes were identified. In total, 1236 and 881 novel related genes were predicted for HBV-associated and -non-associated HCC, respectively. By integrating the predicted genes and shortest path genes in their gene interaction network, we identified 679 common genes involved in the two types of HCC.
Conclusion:
We identified the significantly different genetic features between two types of HCC. We also predicted related genes for the two types based on their specific features. Finally, we determined the common genes and features that were involved in both of these two types of HCC.
Experimental X-ray powder diffraction data, unit-cell parameters, and space group for trelagliptin succinate, C18H20FN5O2•C4H6O4, are reported [a = 18.481(6), b = 8.120(4), c = 7.903(4) Å, α = 89.972(0)°, β = 97.722(4)°, γ = 90.120(0)°, unit-cell volume V = 1175.37 Å3, Z = 2, and space-group P1]. All measured lines were indexed and are consistent with the P1 space group. No detectable impurity was observed.
The genus Sphenothallus was erected by Hall (1847, p. 261), who originally considered it a land plant. Sphenothallus was later classified as a marine invertebrate. Moore and Harrington (1956, p. F65) regarded Sphenothallus as a hydrozoan or scyphozoan. Van Iten et al. (1992, p. 139) supported Moore and Harrington's idea, and argued that it displays a close relationship to conularids (also see Li, 2000, p. 91). However, Mason and Yochelson (1985, p. 93–94) suggested that Sphenothallus is an annelid or “worm” (also see Fauchald et al., 1986, p. 64; Feldmann et al., 1986, p. 344–345; Choi, 1990, p. 403; Bartels et al., 1998, p. 114–117). The exact phylogenetic affinity of Sphenothallus is still debated.
We describe a 31-year-old man with clinically definite multiple sclerosis who presented with intractable hiccup for one month prior to admission. The responsible lesion was confirmed by magnetic resonance imaging to be a plaque in the ventral paramedian portion of the medulla oblongata.
The terricolous lichen Peltigera wulingensis sp. nov. is described from Wuling Mountain, North China. It can be distinguished from other members of the P. rufescens group by its phyllidia along the margin or laminal cracks, scabrose upper surface, lobe extremities with tufts of tiny grey-whitish to pale brown hairs, and its slender, scattered and simple rhizines. Comparisons of the ITS sequences of the nuclear ribosomal DNA repeat tandem support the taxonomic distinctness of this species.
The Critically Endangered Chinese crested tern Sterna bernsteini is a poorly known species. From June 2003 to August 2007 we therefore surveyed the Zhejiang and Shandong coasts of eastern China for breeding colonies and to document any threats. Our results indicated that (1) the colonies at Matzu and Jiushan are the only two in the species' potential breeding range, (2) the total population is no more than 50, (3) numbers in the two extant breeding colonies fluctuate annually, and (4) threats to the breeding populations include habitat degradation, egg poaching, disturbance, overfishing and typhoons. Egg poaching is the greatest threat to the Chinese crested tern population and other breeding seabird populations along the coast of China. We make recommendations for the conservation of this species.
Wheatgrass, Thinopyrum Löve (Elytrigia Nevski), is one of the most important alien resources for wheat improvement. To determine the transferability of wheat microsatellite primers to Thinopyrum spp., 40 wheat microsatellite primer pairs were selected to perform PCR analysis on 17 accessions of Thinopyrum spp. and two common wheat (Triticum aestivum) cultivars. Among the 40 primer pairs used, 25 pairs could produce PCR products on all or most of the alien species. Moreover, all of these 25 primer pairs, except Xgwm325, showed polymorphism in the Thinopyrum accessions. In total, 108 alleles were detected by the 25 primer pairs. The number of alleles per primer pair varied from 1 to 8, with an average of 4.3 alleles per primer. Although primer Xgwm325 did not detect polymorphic alleles in Thinopyrum spp., it could be used as a specific SSR marker for them. It amplified four specific DNA fragments in Thinopyrum spp. of length approximately 1400, 440, 120 and 100 bp. To verify the validity of these molecular markers, a further PCR programme with primer Xgwm325 was conducted on a full set of seven wheat–Thinopyrum elongatum disomic addition lines and 15 disomic substitution lines. This showed that only the 100-bp fragment appeared in all materials possessing the alien chromosome, indicating that it was a molecular marker for the entire genome of Th. elongatum, although primer Xgwm325 was specific for chromosome 6D in wheat.
Ginseng hairy roots were induced from root explants of ginseng by the co-culture of Agrobacterium rhizogenes and ginseng (Panax ginseng C. A. Mey) roots through direct inoculation. The content of ginsenosides in the ginseng hairy roots after 4 weeks of culture reached the same level as in 3-year-old cultivated ginseng roots, and the content of one ginsenoside (Rb1) increased, showing that left transferred DNA (TL-DNA) has a function of influencing the biosynthesis of ginsenosides. Based on analysis of the RiA4TL-DNA sequence, the rolC gene affecting the synthesis of ginsenosides was amplified and cloned from the ginseng hairy roots by PCR. Comparison with a previously published nucleotide sequence showed that the homology was 99.9%.