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A shift towards including more plant-based wholefoods and a reduction in highly processed and animal sourced foods is highlighted by the World Health Organization as a relatively simple, yet impactful way consumers can make their diets more sustainable and healthier for the planet(1). Changing the population’s diet has proven difficult and the threat of obesity and chronic disease development does not appear to have been a strong motivating factor for middle-aged and older adults. Awareness of the facilitators and obstacles that affect healthful dietary choices is important to inform design of nutrition promotion and behaviour change programs. The aim of this study was to synthesise available evidence that reported what middle-aged and older adults described about barriers and enablers to eating foods consistent with sustainable dietary patterns. A convergent integrated mixed methods systematic review was selected as the best method to answer the research question and we followed the Joanna Briggs Institute method(2). The MEDLINE, CINAHL, Scopus and PsychInfo databases were searched for studies published from January 2009 to February 2024 that reported the beliefs, opinions and attitudes of people aged 45-years and older in high-income countries about food selections and barriers and enablers to eating foods generally consistent with sustainable practices. Twenty-four studies met the inclusion criteria and had data extracted and quality critically appraised using the Mixed Methods Appraisal Tool(3). Findings were combined in a narrative review. The enablers included an understanding of environmental impacts of food; knowledge about nutritional benefits of plant foods and of sustainable eating patterns; and awareness of the health and environmental concerns about some animal food sources. The reported barriers included: cost of eating a sustainable diet; a preference for taste of animal foods; anxieties about nutritional adequacy of plant-based diets; cultural factors and no knowledge of diet and sustainability. The findings may be useful in design of education campaigns and health promotion.
Unmanned aerial vehicle (UAV) formations for bearing-only passive detection are increasingly important in modern military confrontations, and the array of the formation is one of the decisive factors affecting the detection accuracy of the system. How to plan the optimal geometric array in bearing-only detection is a complex nondeterministic polynomial problem, and this paper proposed the distributed stochastic subgradient projection algorithm (DSSPA) with layered constraints to solve this challenge. Firstly, based on the constraints of safe flight altitude and fixed baseline, the UAV formation is layered, and the system model for bearing-only cooperative localisation is constructed and analysed. Then, the calculation formula for geometric dilution of precision (GDOP) in the observation plane is provided, this nonlinear objective function is appropriately simplified to obtain its quadratic form, ensuring that it can be adapted and used efficiently in the system model. Finally, the proposed distributed stochastic subgradient projection algorithm (DSSPA) combines the idea of stochastic gradient descent with the projection method. By performing a projection operation on each feasible solution, it ensures that the updated parameters can satisfy the constraints while efficiently solving the convex optimisation problem of array planning. In addition to theoretical proof, this paper also conducts three simulation experiments of different scales, validating the effectiveness and superiority of the proposed method for bearing-only detection array planning in UAV formations. This research provides essential guidance and technical reference for the deployment of UAV formations and path planning of detection platforms.
This paper proposes a cooperative midcourse guidance law with target changing and topology switching for multiple interceptors intercepting targets in the case of target loss and communication topology switching. Firstly, a three-dimensional guidance model is established and a cooperative trajectory shaping guidance law is given. Secondly, the average position consistency protocol of virtual interception points is designed for communication topology switching, and the convergence of the average position of virtual interception points under communication topology switching is proved by Lyapunov stability theory. Then, in the case of the target changing, the target handover law and the handover phase guidance law are designed to ensure the acceleration smoothing, at last, the whole cooperative midcourse guidance law is given based on the combination of the above guidance laws. Finally, numerical simulation results show the effectiveness and the superiority of the proposed cooperative midcourse guidance law.
In a recent survey of nematodes associated with tobacco in Shandong, China, the root-lesion nematode Pratylenchus coffeae was identified using a combination of morphology and molecular techniques. This nematode species is a serious parasite that damages a variety of plant species. The model plant benthi, Nicotiana benthamiana, is frequently used to study plant-disease interactions. However, it is not known whether this plant species is a host of P. coffeae. The objectives of this study were to evaluate the parasitism and pathogenicity of five populations of the root-lesion nematode P. coffeae on N. benthamiana.N. benthamiana seedlings with the same growth status were chosen and inoculated with 1,000 nematodes per pot. At 60 days after inoculation, the reproductive factors (Rf = final population densities (Pf)/initial population densities (Pi)) for P. coffeae in the rhizosphere of N. benthamiana were all more than 1, suggesting that N. benthamiana was a good host plant for P. coffeae.Nicotiana. benthamiana infected by P. coffeae showed weak growth, decreased tillering, high root reduction, and noticeable brown spots on the roots. Thus, we determined that the model plant N. benthamiana can be used to study plant-P. coffeae interactions.
To enhance the performance of anti-ship missiles cooperative attack, this paper proposes a finite-time trajectory shaping-based cooperative guidance law (TSCGL). Firstly, the cooperative guidance model is established on segmented linearisation of the missile’s heading angle. Then, a trajectory shaping guidance law for a single missile is derived by a weighted optimal energy cost function and Schwarz inequality. On this basis, a finite-time TSCGL is proposed combined with trajectory shaping technology and finite-time theory. The desirable finite-time convergence performance can ensure a simultaneous attack. Through an improved method of time-to-go estimation, it is independent of small-angle assumption and relaxes the launching conditions of the missiles. Additionally, the proposed finite-time TSCGL can achieve better damage performance through energy management. Finally, simulation results demonstrate the effectiveness and superiority of the proposed finite-time TSCGL.
In view of the cooperative guidance problem with time delay, this paper proposes a two-stage time-delay prescribed-time cooperative guidance law in the three-dimensional (3D) space. In the first stage, by introducing a time scaling function and time-delay consensus, the proposed cooperative guidance law can overcome the negative influence of time delay to guaranteed the desired convergence performance. Derived from the Lyapunov convergence analysis, the time-delay stability of the first stage can be ensured and the convergence time can be described as the relationship between delayed time and mission-assigned convergence time. Then, taking the prescribed-time-related convergence time as the switching point, the second stage begins with suitable initial conditions and all interceptors are governed by proportional navigation guidance. Finally, comparative simulations are performed to demonstrate the effectiveness and superiority of the proposed time-delay guidance law.
In this paper, to address the cooperative localisation of a heterogeneous UAV swarm in the GNSS-denied environment, an adaptive simulated annealing-particle swarm optimisation (SA-PSO) cooperative localisation algorithm is proposed. Firstly, the forming principle of the communication and measurement framework is investigated in light of a heterogeneous UAV swarm composition. Secondly, a reasonably cooperative localisation function is established based on the proposed forming principle, which can minimise the relative localisation error with limited available information. Then, an adaptive weight principle is incorporated into the particle swarm optimisation (PSO) for better performance. Furthermore, in order to overcome the drawbacks of PSO algorithm easily falling into the local extreme point, an adaptive SA-PSO algorithm is improved to promote the convergence speed of cooperative localisation. Finally, comparative simulations are performed among the adaptive SA-PSO, adaptive PSO, and PSO algorithms to demonstrate the feasibility and superiority of the proposed adaptive SA-PSO algorithm. Simulation results show that the proposed algorithm has better performance in convergence speed, and the cooperative localisation precision can be guaranteed.
South-east Asia's diverse coastal wetlands, which span natural mudflats and mangroves to man-made salt pans, offer critical habitat for many migratory waterbird species in the East Asian–Australasian Flyway. Species dependent on these wetlands include nearly the entire population of the Critically Endangered spoon-billed sandpiper Calidris pygmaea and the Endangered spotted greenshank Tringa guttifer, and significant populations of several other globally threatened and declining species. Presently, more than 50 coastal Important Bird and Biodiversity Areas (IBAs) in the region (7.4% of all South-east Asian IBAs) support at least one threatened migratory species. However, recent studies continue to reveal major knowledge gaps on the distribution of migratory waterbirds and important wetland sites along South-east Asia's vast coastline, including undiscovered and potential IBAs. Alongside this, there are critical gaps in the representation of coastal wetlands across the protected area networks of many countries in this region (e.g. Viet Nam, Indonesia, Malaysia), hindering effective conservation. Although a better understanding of the value of coastal wetlands to people and their importance to migratory species is necessary, governments and other stakeholders need to do more to strengthen the conservation of these ecosystems by improving protected area coverage, habitat restoration, and coastal governance and management. This must be underpinned by the judicious use of evidence-based approaches, including satellite-tracking of migratory birds, ecological research and ground surveys.
Fluid–fluid displacement in porous media has been viewed through the lens of Lenormand's phase diagram since the late 1980s. This diagram suggests that the character of the flow is controlled by two dimensionless parameters: the capillary number and the viscosity ratio. It is by now well known, however, that the wettability of the system plays a key role in determining the pore-scale displacement mechanisms and macroscopic invasion patterns. Here, we endow Lenormand's diagram with the impact of wettability using dynamic and quasi-static pore-network models. By using the fractal dimension and the ratio of characteristic viscous and capillary pressures we delineate the five principal displacement regimes within the extended phase diagram: stable displacement, viscous fingering, invasion percolation, cooperative pore filling and corner flow. We discuss the results in the context of pattern formation, displacement-front dynamics, pore-scale disorder and displacement efficiency.
Manure is a primary source of methane (CH4) emissions into the atmosphere. A large proportion of CH4 from manure is emitted during storage, but this varies with storage methods. In this research, we tested whether covering a manure heap with plastic reduces CH4 emission during a short-term composting process. A static chamber method was used to detect the CH4 emission rate and the change of the physicochemical properties of cattle manure which was stored either uncovered (treatment UNCOVERED) or covered with plastic (treatment COVERED) for 30-day periods during the four seasons? The dry matter content of the COVERED treatment was significantly less than the UNCOVERED treatment (P < 0.01), and the C/N ratio of the COVERED treatment significantly greater than the UNCOVERED treatment (P > 0.05) under high temperature. In the UNCOVERED treatment, average daily methane (CH4) emissions were in the order summer > spring > autumn > winter. CH4 emissions were positively correlated with the temperature (R2 = 0.52, P < 0.01). Compared to the UNCOVERED treatment, the daily average CH4 emission rates from COVERED treatment manure were less in the first 19 days of spring, 13 days of summer, 10 days of autumn and 30 days of winter. In summary, covering the manure pile with plastic reduces the evaporation of water during storage; and in winter, long-term covering with plastic film reduces the CH4 emissions during the storage of manure.
This report is on the synthesis by electrospinning of multiferroic core-shell nanofibers of strontium hexaferrite and lead zirconate titanate or barium titanate and studies on magneto-electric (ME) coupling. Fibers with well-defined core–shell structures showed the order parameters in agreement with values for nanostructures. The strength of ME coupling measured by the magnetic field-induced polarization showed the fractional change in the remnant polarization as high as 21%. The ME voltage coefficient in H-assembled films showed the strong ME response for the zero magnetic bias field. Follow-up studies and potential avenues for enhancing the strength of ME coupling in the core–shell nanofibers are discussed.
Echinococcus granulosus sensu stricto is regarded to have the highest zoonotic potential of all Echinococcus taxa. Globally, human infection due to this species constitutes over 88.44% of the total cystic echinococcosis (CE) burden. Here, we report a CE infection in a Nigerian camel caused by E. granulosus G1 genotype. To the best of our knowledge, this report is the first encounter of the G1 genotype in the West Africa sub-region where the G6 genotype is reportedly prevalent, suggesting that the epidemiology of this highly zoonotic group could have a wider host range and distribution in the sub-region, and emphasizes the need for further investigation into the genetic diversity of Echinococcus spp. in Nigeria and across the sub-region.
We develop a novel ‘moving-capacitor’ dynamic network model to simulate immiscible fluid–fluid displacement in porous media. Traditional network models approximate the pore geometry as a network of fixed resistors, directly analogous to an electrical circuit. Our model additionally captures the motion of individual fluid–fluid interfaces through the pore geometry by completing this analogy, representing interfaces as a set of moving capacitors. By incorporating pore-scale invasion events, the model reproduces, for the first time, both the displacement pattern and the injection-pressure signal under a wide range of capillary numbers and substrate wettabilities. We show that at high capillary numbers the invading patterns advance symmetrically through viscous fingers. In contrast, at low capillary numbers the flow is governed by the wettability-dependent fluid–fluid interactions with the pore structure. The signature of the transition between the two regimes manifests itself in the fluctuations of the injection-pressure signal.
Dietary delivery of bacterially expressed double-stranded RNA (dsRNA) has a great potential for management of Leptinotarsa decemlineata. An important first step is to discover possible RNA-interference (RNAi)-target genes effective against larvae, especially the old larvae. In the present paper, five putative Broad-Complex (BrC) cDNAs (Z1-Z4, and Z6) were identified in L. decemlineata. The expression of the five LdBrC isoforms was suppressed by juvenile hormone signaling, whereas the transcription was upregulated by 20-hydroxyecdysone signaling at the fourth (final) instar larval stage. Feeding of bacterially expressed dsBrC (derived from a common fragment of the five LdBrC variants) in the third- and fourth-instar larvae successfully knocked down the target mRNAs. For the fourth-instar LdBrC RNAi hypomorphs, they had a higher larval mortality compared with the controls. Moreover, most dsBrC-fed beetles did not pupate normally. After removal of the apolysed larval cuticle, a miniature adult was found. The adult head, compound eyes, prothorax, mesothorax, metathorax were found on the dorsal view. Distinct adult cuticle pigmentation was seen on the prothorax. The mouthparts, forelegs, midlegs, and hindlegs could be observed on the ventral view of the miniature adults. For the third-instar LdBrC RNAi specimens, around 20% moribund beetles remained as prepupae and finally died. Therefore, LdBrC is among the most attractive candidate genes for RNAi to control the fourth-instar larvae in L. decemlineata.
Dipetalonema gracile is a common parasite in squirrel monkeys (Saimiri sciureus), which can cause malnutrition and progressive wasting of the host, and lead to death in the case of massive infection. This study aimed to identify a suspected D. gracile worm from a dead squirrel monkey by means of molecular biology, and to amplify its complete mitochondrial genome by polymerase chain reaction (PCR) and sequence analysis. The results identified the worm as D. gracile, and the full length of its complete mitochondrial genome was 13,584 bp, which contained 22 tRNA genes, 12 protein-coding genes, two rRNA genes, one AT-rich region and one small non-coding region. The nucleotide composition included A (16.89%), G (20.19%), T (56.22%) and C (6.70%), among which A + T = 73.11%. The 12 protein-coding genes used TTG and ATT as start codons, and TAG and TAA as stop codons. Among the 22 tRNA genes, only trnS1AGN and trnS2UCN exhibited the TΨC-loop structure, while the other 20 tRNAs showed the TV-loop structure. The rrnL (986 bp) and rrnS (685 bp) genes were single-stranded and conserved in secondary structure. This study has enriched the mitochondrial gene database of Dipetalonema and laid a scientific basis for further study on classification, and genetic and evolutionary relationships of Dipetalonema nematodes.
Cucumber powdery mildew is a destructive foliar disease caused by Podosphaera xanthii (formerly known as Sphaerotheca fuliginea) that substantially damages the yield and quality of crops. The control of this disease primarily involves the use of chemical pesticides that cause serious environmental problems. Currently, numerous studies have indicated that some plant extracts or products potentially have the ability to act as natural pesticides to control plant diseases. It has been reported that turmeric (Curcuma longa L.) and its extract can be used in agriculture due to their insecticidal and fungicidal properties. However, the most effective fungicidal component of this plant is still unknown. In the current study, the crude extract of C. longa L. was found to have a fungicidal effect against P. xanthii. Afterwards, eight fractions (Fr.1–Fr.8) were gradually separated from the crude extract by column chromatography. Fraction 1 had the highest fungicidal effect against this pathogen among the eight fractions. The active compound, (+)-(S)-ar-turmerone, was separated from Fr 1 by semi-preparative high-performance liquid chromatography and identified based on its 1H nuclear magnetic resonance (NMR) and 13C NMR spectrum data. The EC50 value of (+)-(S)-ar-turmerone was found to be 28.7 µg/ml. The compound also proved to have a curative effect. This is the first study to report that the compound (+)-(S)-ar-turmerone has an effect on controlling this disease. These results provide a basis for developing a new phytochemical fungicide from C. longa L. extract.
The musk deer (Moschus berezovskii) is an economically important species from which musk is extracted and used in perfumes and medicines. Cestodes (parasitic flatworms) of the genus Moniezia are important parasites that infect this endangered species and can cause high mortality in young deer. In 1982, Moniezia (S.) sichuanensis sp. nov. was described from a specimen obtained from wild musk deer. The new species was distinct from the other described species of Moniezia by the sawtooth-shaped interproglottidal glands, the thick vagina and the absence of a cirrus spine. In the present study, 12 cestodes collected from musk deer were examined morphologically and confirmed to be M. sichuanensis. Molecular characterization was performed by amplifying and comparing the internal transcribed spacer 1 (ITS1) and 5.8S rRNA gene (ITS1–5.8S) of ribosomal DNA with available sequences from other Moniezia species. The amplified sequences ranged from 761 to 764 bp and similarity ranged from 98.7–100%, compared to 67.8–92.4% with other Moniezia spp. Construction of a phylogenetic tree using the neighbour-joining method indicated that all 12 ITS1–5.8S sequences formed a single clade, confirming M. sichuanensis as a separate species. This study provides novel molecular insight into M. sichuanensis that could prove useful for future diagnosis and control of monieziasis in musk deer.
Macdunnoughia crassisigna Warren (Lepidoptera: Noctuidae) is a highly destructive herbivore that poses a serious risk to cotton, maize, soybean, and cruciferous vegetables in East Asia. Examining the effects of various biotic and abiotic factors on the flight performance of M. crassisigna is crucial for a better understanding of its trans-regional migration. In this study, the flight activity of M. crassisignai moths of different ages, under different temperatures and relative humidity (RH) levels, was evaluated by tethering individuals to computerized flight mills for a 24-h trial period. The results showed that M. crassisignai had the capacity for sustained flight and the flight ability was strongest in 3-day-old individuals, and then their flight performance decreased significantly in older moths. For both sexes, temperature had a significant effect on their flight performance, and the flight activity was relatively higher at 24–28°C than other temperatures. There was a significant effect of RH on all flight parameters of the tested moths, and the flight activity was relatively higher at RH of 60–75% than other RH levels. For 3-day-old moths under the optimum conditions (24°C and 75% RH) throughout the 24 h scotophase, their mean flight distance reached 66 km, and the mean flight duration reached 13.5 h, suggesting M. crassisigna possess strong potential to undertake long-distance migration. These findings will be helpful for developing sound forecasting systems of this pest species.
Studies of schizophrenia at drug-naive state and on antipsychotic medication have reported a number of regions of gray-matter (GM) abnormalities but the reports have been inconsistent. The aim of this study was to conduct multimodal meta-analysis to compare the cross-sectional voxel-based morphometry studies of brain GM in antipsychotic-naive first-episode schizophrenia (AN-FES) and those with antipsychotic treatment within 1 year (AT-FES) to determine the similarities and differences in these groups. We conducted two separate meta-analyses containing 24 studies with a sample size of 801 patients and 957 healthy controls. A multimodal meta-analysis method was used to compare the findings between AN-FES and AT-FES. Meta-regression analyses were done to determine the influence of different variables including age, duration of illness, and positive and negative symptom scores. Finally, jack-knife analyses were done to test the robustness of the results. AN-FES and AT-FES showed common patterns of GM abnormalities in frontal (gyrus rectus), superior temporal, left hippocampal and insular cortex. GM in the left supramarginal gyrus and left middle temporal gyrus were found to be increased in AN-FES but decreased in AT-FES, whereas left median cingulate/paracingulate gyri and right hippocampus GM was decreased in AN-FES but increased in AT-FES. Findings suggest that both AN-FES and AT-FES share frontal, temporal and insular regions as common anatomical regions to be affected indicating these to be the primary regions of GM abnormalities in both groups.