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Time-differenced carrier phase (TDCP) is a commonly used method of precise velocimetry, but when the receiver is in a dynamic or complex observation environment, the estimation accuracy is reduced. Doppler velocimetry aims at estimating instantaneous velocity, and the accuracy is restricted by the accuracy of measurement. However, in such unfavourable cases, the Doppler measurement is more reliable than the carrier phase measurement. This paper derives the relationship between Doppler observation and TDCP observation, then proposes a Doppler enhanced TDCP algorithm, for the purpose of improving the velocity estimation accuracy in dynamic and complex observation environments. In addition, considering the error caused by the constant speed state update model in the robust Kalman filter (RKF), this paper designs a terrain adaptive and robust Kalman filter (TARKF). After three experimental tests, the improved TDCP algorithm can significantly increase the speed measurement accuracy to sub-metre per second, and the accuracy can be further improved after using TARKF.
This experiment was conducted to evaluate the impact of substituting rice straw with citrus pulp (CRP), sweet potato peels (SPP) and vines (SPV) on fermentation quality and in vitro digestibility when ensiled with or without wet brewers' grains (WBG). Seven treatments were set as follows: (i) rice straw only (control); (ii) 800 g rice straw/kg + 200 g CRP/kg (RC); (iii) 720 g rice straw/kg + 180 g CRP/kg + 100 g WBG/kg (RC+); (iv) 800 g rice straw/kg + 200 g SPP/kg (RP); (v) 720 g rice straw + 180 g SPP/kg + 100 g WBG/kg (RP+); (vi) 800 g rice straw/kg + 200 g SPV/kg (RV); (vii) 720 g rice straw/kg + 180 g SPV/kg + 100 g WBG/kg (RV+). After ensiling for 3, 7, 14, 30 and 60 days, silos were opened for fermentation profile, aerobic stability and in vitro parameter analyses. All substitution types improved fermentation quality, characterized by significantly lower pH and NH3-N content, higher lactic acid content and V-scores. WBG application promoted hetero-fermentation and significantly increased DM losses, acetic acid and ethanol contents. After 60 days of ensiling, the NDF, ADF and cellulose contents in mixed silages significantly decreased compared to control. During aerobic exposure, WBG application significantly prolonged aerobic stability. SPV substitution significantly improved in vitro digestibility of dry matter, NDF and ADF. In conclusion, the SPP substitution combined with WBG application was recommended as a result of the optimal balance of fermentation quality, aerobic stability and in vitro digestibility.
The parasite Fasciola hepatica is an important zoonotic parasite. The development of an animal model of F. hepatica's life cycle is critical for studying the biological characteristics of the parasite in snails and mammals. Eggs of F. hepatica of bovine origin were cultured, and metacercariae were obtained after infection of Galba pervia snails. The life cycle system of F. hepatica was initiated in 2 different animals by orally infecting rabbits, SD rats and Kunming mice with the metacercariae. The animals' survival after infection, parasite migration in the animals and pathological damage to the liver were observed. We discovered that rabbits died due to acute suppurative hepatitis 60–69 days after infection, and eggs were found in the feces on day 63 of infection. The liver of SD rats showed punctate lesions on day 3 of infection, and further changes occurred as the infection progressed. However, liver repair was observed at week 9. SD rats survived for more than a year after infection and continued the F. hepatica life cycle. The liver lesions in Kunming mice after infection were similar but more severe than those in SD rats. Death was observed on the 31st post-infection day. We discovered that while rabbits, SD rats and Kunming mice can all be used as animal models of F. hepatica, SD rats are more suitable experimental animals in terms of tolerance and pathological response.
We aimed to investigate the coronavirus disease 2019 (COVID-19)-related knowledge and practices of cancer patients and to assess their anxiety- and depression-related to COVID-19 during the early surge phase of the pandemic.
Methods:
An online questionnaire survey of cancer patients was conducted from February 10-29, 2020. Knowledge and practices related to COVID-19 were assessed using a custom-made questionnaire. The Hospital Anxiety and Depression Scale was used to assess the presence of anxiety and depression, with scores beyond 7 indicating anxiety or depressive disorder. Univariate and multiple linear regression analyses were used to identify the high-risk groups according to the level of knowledge, practices, anxiety, and depression scores.
Results:
A total of 341 patients were included. The rate of lower level of knowledge and practices was 49.9% and 18.8%, respectively. Education level of junior high school degree or lower showed a significant association with lower knowledge score (β: −3.503; P < 0.001) and lower practices score (β: −2.210; P < 0.001) compared to the education level of college degree and above. The prevalence of anxiety and depression among the respondents was 17.6% and 23.2%, respectively. A higher depression score was associated with older age, marital status of the widowed, and lower level of education, knowledge score, and practices score (P < 0.05).
Conclusions:
Targeted COVID-19-related education interventions are required for cancer patients with a lower level of knowledge to help improve their practices. Interventions are also required to address the anxiety and depression of cancer patients.
Pyroptosis is a recently identified mechanism of programmed cell death related to Caspase-1 that triggers a series of inflammatory reactions by releasing several proinflammatory factors such as IL-1β and IL-18. The process is characterised by the rupture of cell membranes and the release of cell contents through the mediation of gasdermin (GSDM) proteins. GSDMD is an important member of the GSDM family and plays a critical role in the two pathways of pyroptosis. Diabetic nephropathy (DN) is a microvascular complication of diabetes and a major cause of end-stage renal disease. Recently, it was revealed that GSDMD-mediated pyroptosis plays an important role in the occurrence and development of DN. In this review, we focus on two types of kidney cells, tubular epithelial cells and renal podocytes, to illustrate the mechanism of pyroptosis in DN and provide new ideas for the prevention, early diagnosis and molecular therapy of DN.
The southeastern Central Asian Orogenic Belt (CAOB) records the assembly process between several micro-continental blocks and the North China Craton (NCC), with the consumption of the Paleo-Asian Ocean (PAO), but whether the S-wards subduction of the PAO beneath the northern NCC was ongoing during Carboniferous–Permian time is still being debated. A key issue to resolve this controversy is whether the Carboniferous magmatism in the northern NCC was continental arc magmatism. The Alxa Block is the western segment of the northern NCC and contiguous to the southeastern CAOB, and their Carboniferous–Permian magmatism could have occurred in similar tectonic settings. In this contribution, new zircon U–Pb ages, elemental geochemistry and Sr–Nd isotopic analyses are presented for three early Carboniferous granitic plutons in the southwestern Alxa Block. Two newly identified aluminous A-type granites, an alkali-feldspar granite (331.6 ± 1.6 Ma) and a monzogranite (331.8 ± 1.7 Ma), exhibit juvenile and radiogenic Sr–Nd isotopic features, respectively. Although a granodiorite (326.2 ± 6.6 Ma) is characterized by high Sr/Y ratios (97.4–139.9), which is generally treated as an adikitic feature, this sample has highly radiogenic Sr–Nd isotopes and displays significantly higher K2O/Na2O ratios than typical adakites. These three granites were probably derived from the partial melting of Precambrian continental crustal sources heated by upwelling asthenosphere in lithospheric extensional setting. Regionally, both the Alxa Block and the southeastern CAOB are characterized by the formation of early Carboniferous extension-related magmatic rocks but lack coeval sedimentary deposits, suggesting a uniform lithospheric extensional setting rather than a simple continental arc.
Two population-based cross-sectional surveys involving randomly selected Chinese adults aged 35–74 years were conducted in Qingdao, China in 2006 and 2009. Nine thousand fifty-five subjects from the two surveys were grouped into four birth groups of fetal/infant exposed (born between 1 January 1959 and 31 December 1962), childhood exposed (born between 1 January 1950 and 31 December 1958), adolescence exposed (born between 1 January 1942 and 31 December 1949) and the unexposed (born before 1941 and after 1963). Multivariate logistic regression models were used to calculate the OR and 95 % CI of hyperuricaemia in different exposed groups. Overall, famine exposure in the fetal/infant period, childhood and adolescence was not associated with adulthood hyperuricaemia (all P > 0·05). In females, childhood exposed group (OR = 1·59, 95 % CI 1·25, 2·02) and adolescence exposed group (OR = 1·74, 95 % CI 1·30, 2·33) both had higher risks to have hyperuricaemia in adult. However, this difference was not found in fetal/infant exposed group. In males, no significant relation was observed in any famine exposed group (all P > 0·05). Exposure to famine in childhood and adolescence is associated with an increased risk of hyperuricaemia for adulthood of females, but not in males. Adequate nutrition during early life appears to be beneficial to prevent hyperuricaemia of adult females.
The prevalence of workplace deviance has become an urgent issue for managers. Although increasing research has investigated the detriments of workplace deviance on other employees and organizations, limited research has studied the harm of workplace deviance on perpetrators themselves. This research drew from appraisal theories of emotion and sought to understand perpetrators' affective and behavioral consequences of engaging in deviance. Using a diary method, a survey consisting of 92 employees with 918 observations was conducted. The results reveal that employees' deviance is positively related to their feeling of fear and that fear overrides feelings of guilt, ultimately decreasing work engagement and organizational citizenship behavior (OCB). Importantly, perceived benevolent leadership weakens the effects of deviance on perpetrators themselves by relieving fear associated with past deviance and mitigating the negative influences of fear on OCB.
This paper is concerned with the asymptotic propagations for a nonlocal dispersal population model with shifting habitats. In particular, we verify that the invading speed of the species is determined by the speed c of the shifting habitat edge and the behaviours near infinity of the species’ growth rate which is nondecreasing along the positive spatial direction. In the case where the species declines near the negative infinity, we conclude that extinction occurs if c > c*(∞), while c < c*(∞), spreading happens with a leftward speed min{−c, c*(∞)} and a rightward speed c*(∞), where c*(∞) is the minimum KPP travelling wave speed associated with the species’ growth rate at the positive infinity. The same scenario will play out for the case where the species’ growth rate is zero at negative infinity. In the case where the species still grows near negative infinity, we show that the species always survives ‘by moving’ with the rightward spreading speed being either c*(∞) or c*(−∞) and the leftward spreading speed being one of c*(∞), c*(−∞) and −c, where c*(−∞) is the minimum KPP travelling wave speed corresponding to the growth rate at the negative infinity. Finally, we give some numeric simulations and discussions to present and explain the theoretical results. Our results indicate that there may exists a solution like a two-layer wave with the propagation speeds analytically determined for such type of nonlocal dispersal equations.
A southern population (S) from Xiushui County (29°1′N, 114°4′E) and a northern population (N) from Shenyang city (41°48′N, 123°23′E) of the cabbage beetle, Colaphellus bowringi vary greatly in their life-history traits, and may serve as an excellent model with which to study the inheritance of life-history traits. In the present study, we performed intraspecific hybridization using the two populations, comparing the key life-history traits (fecundity, development time, body weight, growth rate, and sexual size dimorphism (SDD)) between the two populations (S♀ × S♂ and N♀ × N♂) and their two hybrid populations (S♀ × N♂ and N♀ × S♂ populations) at 19, 22, 25, and 28°C. Our results showed that there were significant differences in life-history traits between the two parental populations, with the S population having a significantly higher fecundity, shorter larval development time, larger body weight, higher growth rate, and greater weight loss during metamorphosis than the N population at almost all temperatures. However, these life-history traits in the two hybrid populations were intermediate between those of their parents. The life-history traits in the S × N and N × S populations more closely resembled those of the maternal S population and N population, respectively, showing maternal effects. Weight loss for both sexes was highest in the S population, followed by the S × N, N × S, and N populations at all temperatures, suggesting that larger pupae lost more weight during metamorphosis. The changes in SSD with temperature were similar between the S and the S × N populations and between the N and the N × S populations, also suggesting a maternal effect. Overall, our results showed no drastic effect of hybridization on C. bowringi, being neither negative (hybrid inferiority) nor positive (heterosis). Rather, the phenotypes of hybrids were intermediate between the phenotypes of their parents.
GBF1 [Golgi brefeldin A (BFA) resistance factor 1] is a member of the guanine nucleotide exchange factors Arf family. GBF1 localizes at the cis-Golgi and endoplasmic reticulum (ER)-Golgi intermediate compartment where it participates in ER-Golgi traffic by assisting in the recruitment of the coat protein COPI. However, the roles of GBF1 in oocyte meiotic maturation are still unknown. In the present study, we investigated the regulatory functions of GBF1 in mouse oocyte organelle dynamics. In our results, GBF1 was stably expressed during oocyte maturation, and GBF1 localized at the spindle periphery during metaphase I. Inhibiting GBF1 activity led to aberrant accumulation of the Golgi apparatus around the spindle. This may be due to the effects of GBF1 on the localization of GM130, as GBF1 co-localized with GM130 and inhibiting GBF1 induced condensation of GM130. Moreover, the loss of GBF1 activity affected the ER distribution and induced ER stress, as shown by increased GRP78 expression. Mitochondrial localization and functions were affected, as the mitochondrial membrane potential was altered. Taken together, these results suggest that GBF1 has wide-ranging effects on the distribution and functions of Golgi apparatus, ER, and mitochondria as well as normal polar body formation in mouse oocytes.
Inflammation has been suggested to play an important role in the development and progression of metabolic syndrome (MetS). Dietary inflammatory index (DII), a measurement of inflammatory potential in diets, was suggested to be associated with MetS. The aim of this systematic review and meta-analysis was to establish the associations of DII with MetS and its components based on available observational studies.
Design:
Systematic review and meta-analysis.
Setting:
A comprehensive literature search of studies that assessed the associations between DII and MetS was conducted in PubMed, Medline and Embase, using a combination of search terms relating to DII and MetS.
Participants:
Eighteen articles were eligible, of which fourteen were cross-sectional and four were cohort in design.
Results:
Results from the random effects meta-analysis showed significantly positive associations of higher DII (top v. bottom quartiles) with MetS (OR: 1·23 (95 % CI 1·10, 1·37)), abdominal obesity (OR: 1·15 (95 % CI 1·02, 1·29)), high blood pressure (OR: 1·17 (95 % CI 1·07, 1·29)), hyperglycaemia (OR: 1·18 (95 % CI 1·05, 1·33)) and hypertriacylglycerolaemia (OR: 1·17 (95 % CI 1·07, 1·28)). The effects of summary OR became stronger when analyses were restricted to cohorts, studies that adjudged for covariates (including BMI, physical activity and total energy intake).
Conclusions:
Higher DII, representing pro-inflammatory diet, is associated with higher odds of MetS and its components, except for low HDL-cholesterol. The findings prompt dietary interventions for preventing MetS from the aspect of inflammation.
X/γ-rays have many potential applications in laboratory astrophysics and particle physics. Although several methods have been proposed for generating electron, positron, and X/γ-photon beams with angular momentum (AM), the generation of ultra-intense brilliant γ-rays is still challenging. Here, we present an all-optical scheme to generate a high-energy γ-photon beam with large beam angular momentum (BAM), small divergence, and high brilliance. In the first stage, a circularly polarized laser pulse with intensity of 1022 W/cm2 irradiates a micro-channel target, drags out electrons from the channel wall, and accelerates them to high energies via the longitudinal electric fields. During the process, the laser transfers its spin angular momentum (SAM) to the electrons’ orbital angular momentum (OAM). In the second stage, the drive pulse is reflected by the attached fan-foil and a vortex laser pulse is thus formed. In the third stage, the energetic electrons collide head-on with the reflected vortex pulse and transfer their AM to the γ-photons via nonlinear Compton scattering. Three-dimensional particle-in-cell simulations show that the peak brilliance of the γ-ray beam is $\sim 1{0}^{22}$ photons·s–1·mm–2·mrad–2 per 0.1% bandwidth at 1 MeV with a peak instantaneous power of 25 TW and averaged BAM of $1{0}^6\hslash$/photon. The AM conversion efficiency from laser to the γ-photons is unprecedentedly 0.67%.
In this paper, the generation of relativistic electron mirrors (REMs) and the reflection of an ultra-short laser off this mirrors are discussed, applying two-dimensional particle-in-cell (2D-PIC) simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapidly expanding. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads the resonance between laser and REM. The reflected radiation near this interval and the corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, certain part of the reflected field could be selectively amplified or depressed, leading to the selectively adjusting of the corresponding spectra.
The orientation between twin boundary (TB) and loading direction may play an intriguing role in the deformation behaviors of twinned metallic materials. In this aspect, its essential effect on the high-entropy alloy (HEA) nanocrystals is elusive. Attention herein is focused on the atomic-scaled deformation mechanisms and fracture behaviors of HEA nanocrystals containing twins of even smaller spacings via a combined approach of in situ tensile tests inside a high-resolution transmission electron microscope and molecular dynamics simulations. The results indicate that the deformation mechanisms (especially dislocation activities) of HEA nanocrystals depend on the load orientation with respect to TBs. Because of the low activation energy and uneven local composition of HEA, the surface acts as an effective dislocation source and, together with Schmid factor, dominate the activated dislocation slip system. The load orientation-dependent TB-dislocation interactions may transform the type of fracture from semi-brittle to ductile. Our results indicate that the deformation mechanisms and the types of fracture in HEA nanocrystals can be controlled by changing the orientation.
To evaluate the effects of dietary Ca intake and Ca supplementation during pregnancy on low birth weight (LBW) and small for gestational age (SGA) infants.
Design:
A birth cohort study was conducted in 2010–2012 at the Gansu Provincial Maternity and Child Care Hospital in Lanzhou, China.
Setting:
A birth cohort study.
Participants:
Totally, 9595 pregnant women who came to the hospital for delivery at 20 weeks of gestation or more, and who were 18 years of age or older.
Results:
Compared with non-users, Ca supplement users had a reduced risk of LBW infants (OR = 0·77, 95 % CI: 0·63, 0·95) and a reduced risk of nulliparous women giving birth to LBW infants (OR = 0·75, 95 % CI: 0·58, 0·98) (P < 0·05). More specifically, both the use of Ca supplement before conception and during pregnancy (OR = 0·44, 95 % CI: 0·19, 0·99) and during pregnancy only (OR = 0·80, 95 % CI: 0·65, 0·99) had the main effect of reducing risk of nulliparous women giving birth to LBW infants (P < 0·05). There was no association between Ca supplementation and SGA (OR = 0·87, 95 % CI: 0·75, 1·01) (P > 0·05). However, higher dietary Ca intake during pregnancy decreases the risk of both LBW (quartile 2: OR = 0·72, 95 % CI: 0·55, 0·94; quartile 3: OR = 0·68, 95 % CI: 0·50, 0·62) and SGA infants (quartile 2: OR = 0·77, 95 % CI: 0·63, 0·95; quartile 3: OR = 0·71, 95 % CI: 0·57, 0·88, quartile 4: OR = 0·71, 95 % CI: 0·57, 0·88) (P < 0·05).
Conclusions:
Ca supplementation and adequate dietary intake of Ca during pregnancy are associated with a decreased risk of LBW infants born to nulliparous women.
The clinical characteristics of patients with COVID-19 were analysed to determine the factors influencing the prognosis and virus shedding time to facilitate early detection of disease progression. Logistic regression analysis was used to explore the relationships among prognosis, clinical characteristics and laboratory indexes. The predictive value of this model was assessed with receiver operating characteristic curve analysis, calibration and internal validation. The viral shedding duration was calculated using the Kaplan–Meier method, and the prognostic factors were analysed by univariate log-rank analysis and the Cox proportional hazards model. A retrospective study was carried out with patients with COVID-19 in Tianjin, China. A total of 185 patients were included, 27 (14.59%) of whom were severely ill at the time of discharge and three (1.6%) of whom died. Our findings demonstrate that patients with an advanced age, diabetes, a low PaO2/FiO2 value and delayed treatment should be carefully monitored for disease progression to reduce the incidence of severe disease. Hypoproteinaemia and the fever duration warrant special attention. Timely interventions in symptomatic patients and a time from symptom onset to treatment <4 days can shorten the duration of viral shedding.