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Environment-induced epigenetics are involved in diapause regulation, but the molecular mechanism that epigenetically couples nutrient metabolism to diapause regulation remains unclear. In this study, we paid special attention to the significant differences in the level of N6-adenosine methylation (m6A) of dihydroxyacetone phosphate acyltransferase (DHAPAT) and phosphatidate phosphatase (PAP) genes in the lipid metabolism pathway of the bivoltine silkworm (Bombyx mori) strain Qiufeng developed from eggs incubated at a normal temperature (QFHT, diapause egg producer) compared to those from eggs incubated at a low temperature (QFLT, non-diapause egg producer). We knocked down DHAPAT in the pupal stage of the QFLT group, resulting in the non-diapause destined eggs becoming diapausing eggs. In the PAP knockdown group, the colour of the non-diapause destined eggs changed from light yellow to pink 3 days after oviposition, but they hatched as normal. Moreover, we validated that YTHDF3 binds to m6A-modified DHAPAT and PAP mRNAs to promote their stability and translation. These results suggest that RNA m6A methylation participates in the diapause regulation of silkworm by changing the expression levels of DHAPAT and PAP and reveal that m6A epigenetic modification can be combined with a lipid metabolism signal pathway to participate in the regulation of insect diapause traits, which provides a clearer image for exploring the physiological basis of insect diapause.
Despite rising incidences of global disasters, basic principles of disaster medicine training are barely taught in Singapore’s 3 medical schools. The aim of this study was to evaluate the current levels of emergency preparedness, attitudes, and perceptions of disaster medicine education among medical students in Singapore.
The Emergency Preparedness Information Questionnaire (EPIQ) was provided to enrolled medical students in Singapore by means of an online form, from March 6, 2020, to February 20, 2021. A total of 635 (25.7%) responses were collated and analyzed.
Mean score for overall familiarity was low, at 1.50 ± 0.74, on a Likert scale of 1 for not familiar to 5 for very familiar. A total of 90.6% of students think that disaster medicine is an important facet of the curriculum, and 93.1% agree that training should be provided for medical students. Although 77.3% of respondents believe that they are unable to contribute to a disaster scenario currently, 92.8% believe that they will be able to contribute with formal training.
Despite low levels of emergency preparedness knowledge, the majority of medical students in Singapore are keen for adaptation of disaster medicine into the current curriculum to be able to contribute more effectively. This can arm future health-care professionals with the confidence to respond to any potential emergency.
Breast cancer is a high-risk disease with a high mortality rate among women. Chemotherapy plays an important role in the treatment of breast cancer. However, chemotherapy eventually results in tumours that are resistant to drugs. In recent years, many studies have revealed that the activation of Wnt/β-catenin signalling is crucial for the emergence and growth of breast tumours as well as the development of drug resistance. Additionally, drugs that target this pathway can reverse drug resistance in breast cancer therapy. Traditional Chinese medicine has the properties of multi-target and tenderness. Therefore, integrating traditional Chinese medicine and modern medicine into chemotherapy provides a new strategy for reversing the drug resistance of breast tumours. This paper mainly reviews the possible mechanism of Wnt/β-catenin in promoting the process of breast tumour drug resistance, and the progress of alkaloids extracted from traditional Chinese medicine in the targeting of this pathway in order to reverse the drug resistance of breast cancer.
No relevant studies have yet been conducted to explore which measurement can best predict the survival time of patients with cancer cachexia. This study aimed to identify an anthropometric measurement that could predict the 1-year survival of patients with cancer cachexia. We conducted a nested case–control study using data from a multicentre clinical investigation of cancer from 2013 to 2020. Cachexia was defined using the Fearon criteria. A total of 262 patients who survived less than 1 year and 262 patients who survived more than 1 year were included in this study. Six candidate variables were selected based on clinical experience and previous studies. Five variables, BMI, mid-arm circumference, mid-arm muscle circumference, calf circumference and triceps skin fold (TSF), were selected for inclusion in the multivariable model. In the conditional logistic regression analysis, TSF (P = 0·014) was identified as a significant independent protective factor. A similar result was observed in all patients with cancer cachexia (n 3084). In addition, a significantly stronger positive association between TSF and the 1-year survival of patients with cancer cachexia was observed in participants aged > 65 years (OR: 0·94; 95 % CI 0·89, 0·99) than in those aged ≤ 65 years (OR: 0·96; 95 % CI 0·93, 0·99; Pinteraction = 0·013) and in participants with no chronic disease (OR: 0·92; 95 % CI 0·87, 0·97) than in those with chronic disease (OR: 0·97; 95 % CI 0·94, 1·00; Pinteraction = 0·049). According to this study, TSF might be a good anthropometric measurement for predicting 1-year survival in patients with cancer cachexia.
In this paper, a wideband bandpass filter using multi-mode resonator and mixed electromagnetic (EM) coupling is presented. To increase the bandwidth while not enlarge the circuit size, multi-short-stub multi-mode resonator, which produces multiple resonances, is utilized. Furthermore, the capacitive gap between open ends of the stubs is utilized to realize electric coupling between the multi-mode resonator and quarter-wavelength stepped impedance resonator. Meanwhile, a high-impedance transmission line between them is used to implement magnetic coupling. This mixed EM coupling can produce transmission zero near the passband, consequently improving the frequency selectivity of proposed filter. Measured results of the filter prototype are in good agreement with the simulated ones. The filter is with an insertion loss at central frequency of 15.86 GHz about 2.5 dB, a 3 dB bandwidth about 5.72 GHz (the fractional bandwidth about 36%), and the variation of group delay over the whole passband <0.28 ns. Additionally, the effective circuit size of the filter is about 0.126 λg2, where λg is the wavelength of 15.86 GHz. All these results have shown that proposed filter is promising for future high-precision imaging system or high-speed communication application.
Tributyltin, an organotin, is ubiquitous in estuaries and freshwater systems. Previous reports suggest that tributyltin is an endocrine disruptor in many wildlife species and it inhibits aromatase in mammalian placental and granulosa-like tumor cell lines. However, no evidence showing the effects of tributyltin on oocytes or preimplantation embryonic developmental competence exists. Therefore, we investigated the role of tributyltin chloride (TBTCl) in the development of female oocytes and preimplantation embryos. Briefly, female ICR mice were gavaged with 0 (vehicle), 4, and 8 mg/kg of TBTCl each day for 18 days. The fluorescence intensity analysis showed that the 5-methylcytosine level decreased after TBTCl treatment, indicating that the general DNA methylation level decreased in the treated oocytes. Our results demonstrate that TBTCl treatment results in decreased mRNA levels of imprinted genes H19, Igf2r, and Peg3 during oocyte growth. The TBTCl-treated oocytes showed a significant increase in reactive oxygen species levels in germinal vesicle oocytes. In TBTCl-treated oocytes, there was no difference in GPx and Sod1 expression, but a decreased mRNA level of Cat occurred when compared with control. Moreover, the blastocysts with TBTCl exposure displayed higher apoptotic signals. These results suggest that TBTCl induces developmental defects in oocytes and preimplantation embryos.
The structural properties, the formation enthalpies, and the mechanical properties of Co–Al compounds (CoAl, CoAl3, Co3Al, Co2Al5, Co2Al9, and Co4Al13) are studied by using Chen's lattice inversion embedded-atom method. The potential is transferable and therefore does well for studying different Co–Al compounds. The calculated lattice parameters and cohesive energies are consistent with the experimental and theoretical results. The formation enthalpies of all the Co–Al compounds are negative; therefore, the chemical bonding between Co and Al atoms increases the stability of compounds. According to elastic constant restrictions, all the six Co–Al compounds are mechanically stable. CoAl alloy with the larger moduli and lower Poisson's ratio is the hard or brittle phase. Moreover, CoAl3, Co3Al, Co2Al5, and Co2Al9 alloys are considered to be ductile materials, which have lower ratio of shear modulus to bulk modulus.
The functional mitochondrial protein alternative oxidase (AOX) gene was used as a marker to analyse the phylogenetic relationship between Cryptosporidium isolates. This gene was characterized, and the phylogentic tree was established from Cryptosporidium isolates and compared to those generated from 18S rRNA and heat-shock protein 70 (HSP70) gene sequences. The present trial aimed at finding out whether the AOX gene is suitable for phylogenetic analysis of the Cryptosporidium genus. The results revealed that the genus Cryptosporidium contained the phylogenetically distinct species C. parvum, C. hominis, C. suis and C. baileyi, which were consistent with the biological characterization and host specificity reported earlier. Cryptosporidium species formed two clades: one included C. hominis, C. suis, C. parvum cattle genotypes and C. parvum mouse genotype; and the other comprised C. meleagridis and C. baileyi isolates. Within C. parvum, both the mouse genotype and the pig genotype I (also known as C. suis) isolates differed from cattle and human (also known as C. hominis) genotypes, based on the aligned nucleotide sequences. The sequence identity of the AOX gene was higher between C. meleagridis and C. baileyi than between C. meleagridis and C. parvum. The phylogenetic trees showed that C. meleagridis was closer to C. baileyi than to C. parvum. This result was inconsistent with the phylogenetic analysis deduced from 18S rRNA and HSP70 gene sequences, respectively. The present results suggest that the AOX gene is not only equally suitable for the phylogenetic analysis of Cryptosporidium, but also provides an outstanding and new approach in determining Cryptosporidium heredity.
On the basis of the first principle interatomic potentials, the site preference of various alloying elements in Fe3Al were evaluated for Ti, Si, Ni, Mn, Mo, and Cr, respectively. The calculated results of the substitutional distribution were in good agreement with the experimental results. Moreover, the calculated results showed that H atoms in Fe3Al prefer to occupy the Fe-type octahedral interstice on the surface, which resulted in concentration of H atoms on the surface. Cr addition decreased the absorbability of Fe3Al-based alloys for H atoms and the force to drive H atoms segregating to surface. The concentration of H atoms on the surface can be decreased by Cr addition.
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