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As three of the members of the delegation of the Botanical Society of America, the authors participated in a 28-day tour of the People’s Republic of China in May and June, 1978. Botanical institutes and universities were visited in nine cities. A list of names and addresses of the collaborators and editors of family treatments for theFlora Reipublicae Popularis Sinicae is supplemented with a bibliography of published floras and significant taxonomic literature issued primarily since the end of the Cultural Revolution. A few observations on herbaria and herbarium practices are included.  相似文献   

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《Palaeoworld》2023,32(3):573-578
The macaque fossils, including mandible fragments, were discovered for the first time from the Taedong River Basin around Pyongyang (TRBP) (the Chongphadae Cave, Hwangju County; the Taehung Cave, Sangwon County; the Maeri Cave, Sungho County), the Democratic People’s Republic of Korea, which represent the first recognized occurrences of fossil M. mulatta in DPRK. Although the only available skull specimens are the mandible including the teeth, the materials display some mandibular and dental feature combinations that might belong to the known species of Macaca mulatta. This discovery indicates that TRBP may be the richest area of Macacina fossils and an evolutionary center for macaques in DPRK. Radiometric dating of the Chongphadae Cave sediment Layer 12 and Layer 13 yielded 34770–27800 and 24980–21340 cal yr BP respectively.  相似文献   

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《Palaeoworld》2022,31(1):116-120
A new fossil species, Stenophlebia ryonsangensis n. sp. (Stenophlebiidae), collected from the Lower Cretaceous non-marine Sinuiju Formation, North Phyongan Province, has the following forewing characters: preserved wing slender and longer than 47.1 mm; Cr long, with three cells below it, and well aligned with distal part of ScP; Sn shorter than Cr, one cell long; supplementary veinlet below Sn aligned with RP2 and about two cells long; base of IR1 five cells distal of base of RP2. This well preserved material is the first odonatan reported in the DPRK. Congeneric species has previously been found in the Lower Cretaceous Yixian Formation of western Liaoning Province, Northeast China, thus the new discovery of Stenophlebia ryonsangensis n. sp. may contribute to evaluating the distribution and migration of Stenophlebidae and may further indicate the close relationship of the fossil layer with the famous Jehol Biota in Northeast China.  相似文献   

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BackgroundAmong the common soil-transmitted helminth infections, hookworm causes the highest burden. Previous research in the southern part of Lao People’s Democratic Republic (Lao PDR) revealed high prevalence rates of hookworm infection. The purpose of this study was to predict the spatial distribution of hookworm infection and intensity, and to investigate risk factors in the Champasack province, southern Lao PDR.MethodologyA cross-sectional parasitological and questionnaire survey was conducted in 51 villages. Data on demography, socioeconomic status, water, sanitation, and behavior were combined with remotely sensed environmental data. Bayesian mixed effects logistic and negative binomial models were utilized to investigate risk factors and spatial distribution of hookworm infection and intensity, and to make predictions for non-surveyed locations.Conclusions/SignificanceHookworm transmission seems to occur within, rather than between villages in Champasack province. We present spatial risk maps of hookworm infection and intensity, which suggest that control efforts should be intensified in the Champasack province, particularly in mountainous areas.  相似文献   

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Michurinist biology was introduced to China in 1948; granted a state supported monopoly in 1952; and reduced to parity with western genetics from 1956. The Soviets exported it through the propaganda agencies Sino Soviet Friendship Association (SSFA) and VOKS (Cultural Relations with Foreign Countries). China’s Ministry of Agriculture achieved broad public awareness and acceptance of Michurinist biology through a translation, publication, and Soviet guest speakers campaign – all managed by a team of agriculturalists led by Luo Tianyu, a veteran CCP (Communist Party) cadre. The campaign grew exponentially, but did not affect university or Chinese Academy of Sciences biology. Luo Tianyu’s failed attempt to force Michurinist biology on a Beijing university triggered its second stage: monopoly status and a ban on “Mendelist-Morganist” biology in teaching, research, and publication. The CCP Central Committee supported this policy believing that Michurinst biology would increase agricultural production for the forthcoming first Five Year Plan; whereas, western genetics had no practical value. Michurinist biology flourished at all levels of education, research, and science literature; Western genetics was completely shut down. This only began to change when the CCP Central Committee became wary of China’s dependency on Soviet technical expertise and failure to fully utilize that of China. Change was further promoted by significant attacks on Michurinist biology by Soviet and East German biologists. Soon, these developments informed China’s “genetics question,” which became a test case for larger questions about the definition of science and the relationship between scientists and the state. Under the guidance of Lu Dingyi’s Central Committee Propaganda Department, the CCP eventually decided that, henceforth, science controversies would only be resolved by the science community; and that monopolies or ideological orthodoxies would not be imposed on science. At the same time, the CCP rescinded Michurinist biology’s monopoly and the ban on western genetics. By the mid-1960s western genetics had successfully restored itself, largely due to the leadership of C. C. Tan, a former student of Dobzhansky. Michurinist biology’s presence shrank and it became marginalized.  相似文献   

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Moringa peregrina is an economically valuable tree of Egyptian deserts. It is used medicinally, provides a highly nutritious supplement to Bedouin diets, provides fodder for livestock, and is used for fire wood. M. peregrina seeds have been a source of high-quality oil for cosmetics and perfumes since antiquity. Due to unmanaged grazing and over-collection, M. peregrina has become one of the most endangered tree species in the Egyptian desert ecosystem. A long-term conservation program is urgently needed to maintain or increase the number and size of M. peregrina populations. Ten populations harboring a total of 130 adult M. peregrina were sampled from three disjunct Wadis in South Sinai (W. Me’ar, W. Fieran and W. Zaghra). Open-pollinated seedlings were electrophoretically analyzed to address two basic questions: (1) how is genetic diversity distributed within and among populations within these three Wadis; and (2) what is the mating system of this species. M. peregrina has a mixed mating system with a selfing rate up to 16% and has limited genetic diversity within and significant genetic differentiation among its populations, the majority of which occurs among Wadis. Direct protection is urgently needed to decrease genetic deterioration within M. peregrina populations and to improve their ability to maintain or improve their population numbers. The priority of in situ conservation should be to conserve a few large well-distributed populations representing different Wadis. Ex situ germplasm collections should be made across the species’ range to ensure a representative sample of its genetic variation. Seed orchards designed to maximize cross-fertilization among unrelated individuals should be established to generate propagules to supplement natural populations.  相似文献   

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Callus originated in microsporangial wall layers and connective tissues of anthers containing uninucleate microspores on Nitsch's or Murashige and Skoog's medium supplemented with growth regulators. A higher percentage of cultures (43) produced callus on Nitsch's medium containing 10 M indole-3-acetic acid + 1 M 6-benzyladenine. After 13–15 weeks, green nodular structures and prominent roots developed in 25% of the cultures on Murashige and Skoog's medium + 10 M -naphthaleneacetic acid + 1 M kinetin. Multiple shoots were induced in this anther-derived callus when subcultured on Murashige and Skoog's medium augmented with 4.44 M 6-benzyladenine + 0.53 M -naphthaleneacetic acid along with 18.75 M polyvinylpyrrolidone. The excised shoots formed roots after subculturing on Murashige and Skoog's medium + 4.90 M indole-3-butyric acid + 18.75 M polyvinylpyrrolidone, thus developing complete plantlets. Examination of callusing anthers also revealed two- to multi-celled pollen masses with intact exine.Abbreviations BA 6-benzyladenine - CW coconut water - 2,4-d 2,4-dichlorophenoxyacetic acid - GA3 gibberellic acid - HCl hydrochloric acid - IAA indole-3-acetic acid - IBA indole-3-butyric acid - KMnO4 potassium permanganate - MS Murashige & Skoog's medium - NAA -naphthaleneacetic acid - NB Nitsch's medium - PVP polyvinylpyrrolidone  相似文献   

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To check feasibility and effectiveness of the α-amylase reporter system, two vectors were designed and tested using hepatitis B virus surface antigen (HBsAg) and Homo sapiens granulocyte-macrophage colony stimulating factor 2 (hGM-CSF2) as a model. By integrating the vector containing two independent cassettes into the same genome locus, high-producing clones of HBsAg (or hGM-CSF2) were screened using the α-amylase as a reporter. Results show there was a positive correlation (Correlation coefficient, R 2 > 0.95) between the yield of recombinant proteins and the α-amylase activity of corresponding transformants, which was independent of the gene dosage.  相似文献   

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It has well been known that human and rodents exhibit a preference for fats. This suggests the existence of an orosensory system responsible for the detection of dietary fats. A plasma membrane glycoprotein CD36, besides the role in the uptake of long-chain fatty acids (LCFAs) as well as oxidized low-density lipoprotein (OxLDL) in a variety of cells, has been postulated to be a candidate fat taste receptor on the tongue. Therefore, molecules that bind with CD36 to cause intracellular signaling but have fewer calories could be substitutes for dietary fats. In the present study, we developed an in vitro system for the screening of CD36 ligands using Chinese hamster ovary-K1 cells (CHO-K1) stably transfected with human or mouse CD36. When incubated with OxLDL labeled with fluorescence dye, the fluorescence was much higher in the transfected CHO-K1 cells than in non-transfected CHO-K1 cells. Incubation of the transfected cells with OxLDL caused a rapid phosphorylation of extracellular signal regulated kinase, and the degree was significantly higher compared with that in non-transfected CHO-K1 cells. The expression system using CHO-K1 cells could be a convenient tool to screen the novel ligands of CD36.  相似文献   

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Herbaceous plant diversity including rare aquatic species has been lost in many countries by agricultural intensification and abandonment. In paddy fields of the Lao People’s Democratic Republic (Lao PDR), irrigation facilities have been constructed rapidly since 1997. The aim of this study was to clarify the impacts of double rice cropping accompanied by the introduction of irrigation systems on herbaceous plant diversity and utilization in paddy fields of southern Lao PDR. Ground vegetation surveys and interviews were conducted in Kok Deau and Lak 30 villages in Champasak Province, and propagule bank survey was conducted in Kok Deau village. The species richness and species diversity, measured by the Shannon’s diversity index, were not significantly different between the irrigated and rainfed paddies (p?>?0.05), when compared in both the wet and dry seasons. However, double rice cropping with irrigation systems affected herbaceous plant species composition in paddy fields. Increased use of chemical fertilizers in irrigated paddies resulted in predominance of tall undesirable species, such as Fimbristylis miliacea (L.) Vahl and Echinochloa colona (L.) Link. Small and frequently submerged species were dominant in the ground vegetation and propagule banks of the rainfed paddies. Since small submerged species are often sensitive to environmental changes, increase of irrigated paddy area may lead to a decrease in the variety of aquatic herbaceous plants in Lao PDR. While a total of 9 herbaceous plant species were utilized as foods in the villages, no change was recognized by farmers in species composition and frequency of utilization of paddy plants as food before and after the development of the irrigation systems.

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Bulk density can be a key indicator of performance, and may influence choice of formulation route of materials in pharmaceutical development. During early development, the cost of API’s can be expensive and the availability of material for powder property analysis is limited. The aim of this work was to investigate a suitable small-scale, low material requirement, bulk density test which would provide comparable data to the recommended large volume USP test. Materials with a range of morphological characteristics typically seen in the pharmaceutical industry were assessed to ensure that methods were suitably robust. It was found that the USP II “low volume” test does not give equivalent results to other tests in the USP, across the range of materials. An alternative test based on the FT4 powder rheometer at a scale of 25 mL gave results equivalent to the large volume USP I standard test. The use of smaller 10-mL methods was also found to give acceptable results for materials that were considered well-behaved but were more variable with difficult to handle materials with low bulk density.KEY WORDS: active pharmaceutical ingredient (API), bulk density, compressibility index, excipients, pharmaceuticals  相似文献   

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Plutella xylostella and Pieris rapae are the key components of a pest complex that attacks Brassica crops in the Democratic People’s Republic of Korea (DPRK). We examined the spatial distributions of these insects within crops both as individual species and when combined as a standard insect that was derived from their relative feeding rates. The influence of standard co-operative management practice and an integrated pest management (IPM) strategy on the dispersion of the standard insect was tested. Iwao’s m* − m relation was then used to describe the distribution of standard insects by management categories and of Pieris rapae using all data. Pest management practices only affected the distribution of the species when they were combined into standard insects. Enumerative sampling plans were therefore designed for standard insects based on population data derived from IPM-managed fields and for Pieris rapae from population data from all experimental fields. The presented plans have the potential to make a significant contribution to managing lepidopteran pests in the DPRK. The approach will be useful in the design of sequential sampling plans for other geographical regions where these pests co-occur and can also contribute to the development of sequential sampling plans for other pest complexes for which standard insects can be derived.  相似文献   

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Mesophilic glucuronidases are the most widely used reporters of gene expression in plants, but unsuitable as reporters in (hyper-)thermophiles due their insufficient thermal stability. Here we present the native 66.8 kDa thermostable β-glucuronidase of Sulfolobus solfataricus. The enzyme activity is characterized in a wide temperature range ideal for, but not limited to, in vivo genetic study of hyperthermophiles. As a proof of concept, we demonstrate its use as a reporter of gene expression in Sulfolobus, by monitoring a promoter fusion created with the β-glucuronidase coding gene gusB and a copper-responsive promoter.  相似文献   

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Based on 224 face-to-face household surveys in an ecologically fragile grazing area in China’s Inner Mongolia Autonomous Region, this study analyzes herder (pastoralist) adaptive capacity for coping with climate change. The Composite Indicator Framework Method and Entropy Weighting Method were applied to calculate each herder’s Adaptive Capacity Index (ACI) based on 16 indicators from seven determinants of adaptive willingness and adaptive capital. Results show that herders have an average ACI value of 0.40. Classifying herders into three groups of relatively high, medium, and low ACI values, we find that financial capital and social capital are the most significant determinants of herder adaptive capacity. Improving financial services and building herder social capital would be the most effective ways of enhancing adaptive capacity for coping with climate change. The methods and indicators developed can be generalized to other similar areas to facilitate better policy interventions for reducing poverty and improving rangeland management.  相似文献   

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Chinese and Russian scientific literature is reviewed, research centers studying pathology of fish and of other aquatic organisms are pointed out. Comparative analysis of scientific problems and of objects of the laboratories and institutes of Russian and China is made. Our original data are presented on the rapid method of early diagnosis of fish diseases.  相似文献   

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