The Special Expression and Comparison of the c-kit Protein in Spermatogenesis of Three Species of Locusts of Arcypteridae

The aim of this study was to elucidate the expression and regulation of the c.kit protein in spermatogenesis of locusts. Immunohistochemistry and biological statistics were used to investigate the expression of the c-kit protein in four representative phases of spermatogenesis of three dominant species of locusts of Arcypteridae （Orthoptera： Acridoidea）, namely, Omocestus viridulus （Linnaeus）, Euchorthippus unicolor （Ikonn.）, and Euchorthippus vittatus Zheng, and so on, in Siping area of Jilin Province, China. The results revealed the following： （1） There was weak positive expression of the c-kit protein in spermatogonia and the positive granules were thinner; （2） there was a strong positive expression of the c-kit protein in primary spermatocyte and the positive granules became the largest than in all developmental stages; （3） the c-kit protein positive expression became stronger in secondary spermatocyte, while the positive granules became thinner; （4） there was strong positive expression of the c-kit protein and the positive granules were thinner in mature sperm, which were distributed on its head and tail; （5） there were strong positive protein granules massing at the end of spermary; （6） the positive intensity of the c-kit protein in spermatogenesis was significantly different among different species of locusts. The data suggested that the c-kit protein may play a crucial role in spermatogenesis as well as maintain the physiological action of sperms and fertilization, regulate the developmental speed of spermatogenesis, and/or maintain species isolation, etc.

Regulation of the growth of sprouting roots of black locust seedlings using root barrier panels

How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increases its growing area with sprouting roots and the elongation of horizontal roots at a soil depth of 10 cm.Therefore,a method to regulate the development of horizontal roots could be eff ective in slowing the invasiveness of black locust.In this study,root barrier panels were tested to inhibit the growth of horizontal roots.Since it is labor intensive to observe the growth of roots in the fi eld,it was investigated in a nursery setting.The decrease in secondary fl ush,an increase in yellowed leafl ets,and the height in the seedlings were measured.Installing root barrier panels to a depth of 30 cm eff ectively inhibit the growth of horizontal roots of young black locust.

Species composition and influencing factors of understory woody species in Robinia pseudoacacia plantations on the Loess Plateau

Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tablelands was significantly lower than in the gully stands.Regenerated black locust(19.76%)and Rubus corchorifolius L.f.(64.85%)were the most abundant understory tree and shrub species,respectively,in the tableland stands;Broussonetia papyrifera(L.)L’Hér.ex Vent.(6.77%)and Acanthopanax senticosus(Rupr.Maxim.)Harms.(37.22%)were most abundant in the gully stands.Species richness(S),Shannon diversity(H),and evenness index(J)of the understory plants were significantly lower in the tableland stands than in the gully stands.More diverse understory species and community structures occurred in the gully stands.Differences in species diversity among landform positions may be attributed to differences in soil moisture.In addition,77.57%of the variation in understory species composition was explained,among which shrub and herb coverage,stand age,leaf area index,slope and total soil phosphorus in the 10-20 cm layer were the main factors.Soil organic carbon and total potassium significantly impacted S,H and J.Considering the environmental conditions and the biological characteristics of the plants investigated,R.corchorifolius should be given priority in the development of tableland stands,while B.papyrifera and Celtis sinensis Pers.should form mixed forests with black locust in gully stands.This management could promote biodiversity and stability of the existing black locust plantations but also optimize regional landscape patterns.

小型堆安全壳抑压系统瞬态特性研究

为进一步优化小型堆安全壳抑压系统设计,消除工程设计风险,需要对抑压系统瞬态特性开展研究。本文采用热工水力系统分析软件LOCUST建立了小型堆安全壳抑压系统瞬态计算模型,模拟计算了波动管破口事故及喷淋管破口事故两种工况下抑压系统的瞬态响应,得到系统不同部件的压力、温度等关键参数随时间变化的响应,并分析了不可凝气体对系统瞬态特性的影响。结果表明,抑压管入口流量波动越剧烈,抑压管内压力振荡越强;不可凝气体在一定程度上可以减小抑压管内的振荡,进入抑压系统的不可凝气体成分越多,抑压系统压力越高,温度越低。

Effects of Dietary Straw Content on Growth and Development of Locusta migratoria and Its Egg Hatching

[Objectives]This study was conducted to investigate the effects of dietary straw content on the growth and development of oriental migratory locusts(Locusta migratoria),as well as the effects of temperature and substrate on their egg hatching.[Methods]The eggs of oriental migratory locusts were hatched at 15,20,25,30,35,and 40℃in sawdust,soil and sawdust+soil conditions,respectively,to determine suitable environmental conditions for artificial hatching of oriental migratory locusts.Rice straw was added at 0%,20%,40%,60%,80%and 100%to the basic diet,and the obtained diets was feed to oriental migratory locusts at the 4^(th)instar,to investigate the effects on their growth and development.[Results]The eggs of oriental migratory locusts had a good hatching rate at 25-30℃,and sawdust was the best choice for their hatching substrate.Adding 40%of rice straw to the diet could ensure the normal growth and development of oriental migratory locusts while consuming as much rice straw as possible.[Conclusions]This study explored a technical solution for efficiently producing insect protein from discarded crop straw(treating waste with insects,and turning waste into treasure),providing support for breeding of oriental migratory locusts and locust disaster prevention.

CO/FT调节元件与植物开花时间调节研究进展

综述了CO/FT调节元件与植物开花时间调节的最新研究进展。开花是植物由营养生长向生殖生长转变的关键过程。光周期和温度在植物开花时间控制中起主要作用。在拟南芥和水稻中,CONSTANS(CO)对植物的日照长度测定至关重要,它与其靶基因FLOWERINGLOCUST(FT)构成的调节元件(regulon)在依赖于光周期的开花过程中起重要作用。目前已从多种植物中鉴定出CO和FT基因,并对其在开花时间的调控作用进行了深入研究。

Egg tanning improves the efficiency of CRISPR/Cas9-mediated mutant locust production by enhancing defense ability after microinjection

The mutant efficiency and hatching ratio are two key factors that significantly affect the construction of genome-modified mutant insects.In the construction of CRISPR/Cas9-mediated dsLmRNase2^(–/–)mutant locusts,we found that the tanned eggs which experienced a 20-min contact with the oocyst exhibited a higher success rate compared to fresh newly-laid eggs that were less tanned.However,the heritable efficiency of the dsLmRNase2 deletion to the next generation G_(1 )progeny was similar between adults derived from the tanned or less tanned engineered eggs.Further,the similar effective mutant ratios in the normally developed eggs and G_(0) adults of tanned and less tanned eggs also indicated that tanning did not reduce the absolute mutation efficiency induced by CRISPR/Cas9.Moreover,we found that the syncytial division period,which was longer than the time for tanning,conferred a window period for microinjection treatment with efficient mutation in both tanned and less tanned eggs.We further found that tanned eggs exhibited a higher hatching rate due to a reduced infection rate following microinjection.Both the anti-pressure and ultrastructure analyses indicated that the tanned eggs contained compressed eggshells to withstand increased external pressure.In summary,tanned eggs possess stronger defense responses and higher efficiency of genome editing,providing an improved model for developing Cas9-mediated gene editing procedures in locusts.

美国陆军大力发展托盘化高能激光武器

近来年,美国开展了多种作战概念研究、新型装备研制和前沿技术探索,以应对高端威胁。2022年美国陆军大力发展具有反无人机分层防御能力的托盘化高能激光武器(PHEL),将通过原型样机的开发与演示实验来了解其作战效能对作战的影响,并借此对作战条令进行调整。托盘化高能激光武器是美“分层防御”战略思想下嵌入“托盘化武器”概念相结合的产物,将极大地提升高能激光武器在未来多域作战中的防空反导与打击能力。

基于ECC安注热混合试验的LOCUST 1.2分析与验证

在失水事故(LOCA)工况下安注系统投入使用时,蒸汽与安注冷却剂会发生流体热力学混合,热混合过程中冷腿段的冷却是直接影响堆芯再淹没与否的重要因素。中国广核集团有限公司自主研发了一款两相流热工水力系统分析软件LOCUST,可用于压水堆核电厂事故工况的分析计算。基于西安交通大学堆芯应急冷却系统(ECCS-XJTU)试验台架进行的堆芯应急冷却(ECC)安注热混合试验,本文使用LOCUST软件对ECC热混合试验进行了几何建模及计算分析。ECC热混合试验工况主要为不同流量下主管纯蒸汽与安注管过冷水的混合,蒸汽流量为25~125 kg/h,过冷水流量为100~500 kg/h。模拟计算结果和试验结果的对比分析表明:试验段出口质量流量计算值的最大相对误差在13.8%以内,混合后温度计算值的最大相对误差在8%以内,LOCUST在计算高温蒸汽和过冷水混合时的计算结果相对保守,总体上验证了LOCUST在LOCA下两相热混合安注计算的可靠性和准确性。

Long-term impact of municipal sewage irrigation on treated soil and black locust trees in a semi-arid suburban area of Iran

The effects of municipal sewage irrigation on the soil and black locust （Robinia pseudoacacia L.） tree were studied. For this purpose, two artificial black locust stands under irrigation of municipal sewage and well water were selected in south of Tehran, Iran. Data were collected using technique of systematic random sampling with 4 replicates in each stand. It was found that the growth of black locust tree, as indicated by diameter at breast height, total height, crown length, average crown diameter, basal area and volume, in sewage irrigation stand was much higher than that of well water irrigation stand （P 〈 0.01）. Plant analysis indicated that concentrations of leaf nutrients （N, E K, Ca, Mg, Na, Fe, Mn, Cu and Zn） were greater in sewage-irrigated trees, without toxicity to the minerals of tree leaf, than those of well waterirrigated trees, and positively correlated with their respective value in soil. Ni, Cr and Pb were not detected in leaf samples. Application of sewage resulted in a 1.5-fold increase in the concentrations of soil nutrients, Ni, Cr and Pb. Among these minerals only Pb and Ni in some soil samples exceeded the toxicity limit. The increase in pH, electrical conductivity （EC） and organic carbon of soil was also observed in sewage irrigation. Results confirm that besides the use as irrigation water, municipal sewages are also a potential source of plant nutrients. However, significant accumulation of heavy metals such as Pb and Ni in soil needs to be monitored.

Biomechanical and dynamic mechanism of locust take-off

The biomimetic locust robot hopping vehicle has promising applications in planet exploration and reconnaissance. This paper explores the bionic dynamics model of locust jumping by using high-speed video and force analysis. This paper applies hybrid rigid-flexible mechanisms to bionic locust hopping and studies its dynamics with emphasis laid on the relationship between force and jumping performance. The hybrid rigid-flexible model is introduced in the analysis of locust mechanism to address the principles of dynamics that govern locust joints and mechanisms during energy storage and take-off. The dynamic response of the biomimetic mechanism is studied by considering the flexi- bility according to the locust jumping dynamics mechanism. A multi-rigid-body dynamics model of locust jumping is established and analyzed based on Lagrange method; elastic knee and tarsus mechanisms that were proposed in previous works are analyzed alongside the original bionic joint configurations and their machinery principles. This work offers primary theories for take-off dynamics and establishes a theoretical basis for future studies and engineering applications.

Attenuation of oxidative stress and hepatic damage by some fermented tropical legume condiment diets in streptozotocin-induced diabetes in rats

Objective:To investigate the modulatory effect of fermented legume condiments diet on oxidative stress in streptozotocin(STZ) induced diabetic rats.Methods:Adult male Wistar rats were randomly divided into six groups with six animals in each group.Diabetes was induced by intraperitoneal injection of STZ(35 mg/kg b.w.).After being confirmed diabetic,the rats were fed with fermented Bambara groundnut.Locust bean and Soybean diets for 14 days.The plasma was obtained after 14-day treatment and analyzed for hepatic damage marker enzymes(AST,ALT and ALP) and in vivo antioxidant indices.Results:The diabetic untreated rats showed elevated (P【0.05) levels of AST,ALT.ALP and malondialdehyde with reduced activities of glutathiones -transferase,catalase as well as plasma reduced glutathione,vitamin C and total protein content.However,treatment of diabetic rats with lermenled legume condiments diets for 14 days significantly(P【0.05) reversed the above parameters towards normalcy,suggesting their modulation of oxidative stress,which mav be due to their high phenolic content and antioxidant capacity.Conclusions:The attenuation of oxidative stress and protection of hepatic tissue damage by the legume condiment diets in STZ induced diabetic rats compare favourably with that of metformin,a well known oral hypoglycemic drug.

Using an image segmentation and support vector machine method for identifying two locust species and instars

Locusts are agricultural pests around the world. To cognize how locust distribution density and community structure are related to the hydrothermal and vegetation growth conditions of their habitats and thereby providing rapid and accurate warning of locust invasions, it is important to develop efficient and accurate techniques for acquiring locust information. In this paper, by analyzing the differences between the morphological features of Locusta migratoria manilensis and Oedaleus decorus asiaticus, we proposed a semi-automatic locust species and instar information detection model based on locust image segmentation, locust feature variable extraction and support vector machine(SVM) classification. And we subsequently examined its applicability and accuracy based on sample image data acquired in the field. Locust image segmentation experiment showed that the proposed GrabCut-based interactive segmentation method can be used to rapidly extract images of various locust body parts and exhibits excellent operability. In a locust feature variable extraction experiment, the textural, color and morphological features of various locust body parts were calculated. Based on the results, eight feature variables were selected to identify locust species and instars using outlier detection, variable function calculation and principal component analysis. An SVM-based locust classification experiment achieved a semi-automatic detection accuracy of 96.16% when a polynomial kernel function with a penalty factor parameter c of 2 040 and a gamma parameter g of 0.5 was used. The proposed detection model exhibits advantages such as high applicability and accuracy when it is used to identify locust instars of L. migratoria manilensis and O. decorus asiaticus, and it can also be used to identify other species of locusts.

Ways to Improve Low-Benefit Black Locust Forests in Loess Plateau

This paper presents a general standard for the low-benefit black locust （Robinia pseudoacacia L.） torests m Loess Plateau based on defining the concept of “tri-low forest”, and emphasizes the major factors which result in low-benefit black locust, such as, lack of soil moisture of forest and nutrient, breaching the principle of matching tree species to sites, and high density of forests. Based on different characteristics of low-benefit forests, following the principle of “adjusting measures to local conditions, giving priority to ecological benefits, assisting with economic benefits”, the authors put forward some technical ways to reform low-benefit black locust forests, for example, taking measurements of collecting runoff and storing water, lowering the forest density, introducing mixed forests and transforming species, directive breeding and so on.

Molecular and morphological data confirmed the presence of the rare species Mattirolomyces terfezioides in China

Although the species Mattiwlomyces terfezioides(≡ Terfezia terfezioides) has been recorded from China several times but it is really rare taxon with important ecological and economic value,the conspecihcity with European material has never been tested by molecular data.We re-examined three specimens labelled as T.terfezioides,one as T.leonis and one as Terfezia sp.in the herbarium HMAS and obtained five ITS and three LSU sequences.Our morphological observation and DNA sequences show that one specimen(HMAS 83766) labelled as M.terfezioides turns out to be Choiromyces sp.and the other four are M.terfezioides.The ITS and(or) LSU sequences of the Chinese samples are identical with or with 99%similarity to those from the European samples,which fully confirms the presence of M.terfezioides in China.The species is currently known from northern China(Hebei Province,Beijing and Shanxi Province).This study shows that M terfezioides has a Euroasia distribution other than European endemism and such distribution might be explained by the co-occurrence with the potential host tree Robinia pseudoacacia.

Recent Advances in the Preparation, Characterization and Applications of Locust Bean Gum-Based Films

Locust bean gum(LBG)is a typical galactomannan isolated from carob bean(Ceratonia siliqua L.)cultivated in the Mediterranean area.Due to its superior biodegradable,rheological and film-forming properties,LBG has been used alone or combined with other biopolymers(e.g.,polysaccharides,proteins and lipids)to develop films.Till now,different kinds of functional ingredients(e.g.,montmorillonite,bacteriocins,antibiotics,plant extract,essential oils and microbial cells)have been added into LBG-based films.Notably,the physical and functional properties of LBG-based films are affected by many factors,such as the structure of LBG,the type and content of other biopolymers and functional ingredients,and the physical treatment of film-forming solution.LBG-based films can be not only used as active packaging and edible coating in food industry but also used as wound dressings in pharmaceutical industry.For the first time,this review focuses on the recent advances in the preparation,characterization,physical and functional properties,and potential applications of LBG-based films.

Impact of Robinia pseudoacacia stand conversion on soil properties and bacterial community composition in Mount Tai,China

Background:Robinia pseudoacacia is a widely planted pioneer tree species in reforestations on barren mountains in northern China.Because of its nitrogen-fixing ability,it can play a positive role in soil and forest restoration.After clearcutting of planted stands,R.pseudoacacia stands become coppice plantations.The impacts of shifting from seedling to coppice stands on soil bacterial community and soil properties have not been wel described.This study aims to quantify how soil properties and bacterial community composition vary between planted seedling versus coppice stands.Methods:Nine 20 m×20 m plots were randomly selected in seedling and coppice stands.The bulk soil and rhizosphere soil were sampled in summer 2017.Bulk soil was sampled at 10 cm from the soil surface using a soil auger.Rhizosphere soil samples were col ected using a brush.The soil samples were transported to the laboratory for chemical analysis,and bacterial community composition and diversity was obtained through DNA extraction,16 S r RNA gene amplification and high-throughput sequencing.Results:The results showed that,compared to seedling plantations,soil quality decreased significantly in coppice stands,but without affecting soil exchangeable Mg^(2+) and K^(+).Total carbon(C)and nitrogen(N)were lower in the rhizosphere than in bulk soil,whereas nutrient availability showed an opposite trend.The conversion from seedling to coppice plantations was also related to significant differences in soil bacterial community structure and to the reduction of soil bacterialα-diversity.Principal component analysis(PCA)showed that bacterial community composition was similar in both bulk and rhizosphere soils in second-generation coppice plantations.Special y,the conversion from seedling to coppice stands increased the relative abundance of Proteobacteria and Rhizobium,but reduced that of Actinobacteria,which may result in a decline of soil nutrient availability.Mantel tests revealed that C,N,soil organic matter(SOM),nitrate nitrogen(NO^(-)+(3)-N)and available phosphorus positively correlated with bacterial community composition,while a variation partition analysis(VPA)showed that NO^(-)+(3)-N explained a relatively greater proportion of bacterial distribution(15.12%),compared with C and SOM.Surprisingly,N showed no relationship with bacterial community composition,which may be related to nitrogen transportation.Conclusions:The conversion from seedling to coppice stands reduced soil quality and led to spatial-temporal homogenization of the soil bacterial community structure in both the rhizosphere and bulk soils.Such imbalance in microbial structure can accelerate the decline of R.pseudoacacia.This may affect the role of R.pseudoacacia coppice stands in soil and forest restoration of barren lands in mountain areas.

Temporal changes in nitrogen acquisition of Japanese black pine(Pinus thunbergii) associated with black locust(Robinia pseudoacacia)

The alien woody legume, black locust （Robinia pseudoaca-cia）, has invaded Japanese black pine （Pinus thunbergii） forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests after nematode infestation. Nitrogen fixation by legumes acceler-ates N cycling in forest ecosystems. We studied temporal change in the annual tree-ring resolution N stable isotope composition （δ15N, a per mil deviation of δ15N/14N ratio, relative to atmospheric N2δ15N=0‰） at two natural locations of Japanese black pine forest with black locust that differed in the time since black locust establishment （Shohnai in north-east and Kita-Kyushu in southwest Japan）. Analyzed tree-rings covered the period from 1990/1992 to 2009. N acquisition by Japanese black pine from black locust N input to the soil was evidenced by temporal shifting of N stable isotope composition on the annual pine tree rings. With pro-gressive development of the forest stand,δ15N values of earlier tree-ringsδ15N of -5‰） from black pine associated with black locust shifted to-wards values similar to those of black locustδ15N values nearly to-1‰）, which suggests acquisition of N by N2 fixation （Shohnai site）. In con-trast, in a forest where black locust had settled for two or three genera-tions, in a black pine stand （Kita-Kyushu site）, longer periods of N en-richment in the soil were reflected in the elevated tree-ringδ15N values of newly established black pine trees. Based on tree-ringδ15N data from the Shohnai site, we determined that about 10 years after black locust establishment, soil N had already been enriched by black locust N, this, in turn, contributed to N fertilization of surrounding trees in mixed stands.

IPM-Biological and integrated management of desert locust

Locusts have caused periodic disasters in the recorded history of humankind.Up to now,locust disaster is still the biggest threat to the world’s agricultural production.The desert locust Schistocerca gregaria is one of the most harmful locusts,which has caused massive food crises,economic losses,and ecological disasters.The desert locust is a migratory insect pest that occurs year-round in the tropic and subtropical regions.Under the wind and seasonal alternation,it moves and flies in the African continent and West Asia.Desert locust damages the stems and leaves of more than 300 plants,including Gramineae,Tribulus terrestris,and Euphorbiaceae.Locusts cause devastating disasters to local plants,especially field crops,and significantly threaten food security.To date,voluminous research has been conducted regarding the ecology and management of desert locusts.This review represents an effort to summarize the basic information on the biology and ecology,distribution,damage,and economic impact of desert locusts,examine the recent developments in integrated locust management,and make recommendations for future research.

Dynamic model and performance analysis of landing buffer for bionic locust mechanism

The landing buffer is an important problem in the research on bionic locust jumping robots, and the different modes of landing and buffering can affect the dynamic performance of the buffering process significantly. Based on an experimental observation, the different modes of landing and buffering are determined, which include the different numbers of landing legs and different motion modes of legs in the buffering process. Then a bionic locust mechanism is established, and the springs are used to replace the leg muscles to achieve a buffering effect. To reveal the dynamic performance in the buffering process of the bionic locust mechanism, a dynamic model is established with different modes of landing and buffering. In particular, to analyze the buffering process conveniently, an equivalent vibration dynamic model of the bionic locust mechanism is proposed.Given the support forces of the ground to the leg links, which can be obtained from the dynamic model, the spring forces of the legs and the impact resistance of each leg are the important parameters affecting buffering performance, and evaluation principles for buffering performance are proposed according to the aforementioned parameters. Based on the dynamic model and these evaluation principles, the buffering performances are analyzed and compared in different modes of landing and buffering on a horizontal plane and an inclined plane. The results show that the mechanism with the ends of the legs sliding can obtain a better dynamic performance. This study offers primary theories for buffering dynamics and an evaluation of landing buffer performance,and it establishes a theoretical basis for studies and engineering applications.