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1.
J Insect Sci ; 24(4)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39023176

RESUMO

Tephritis angustipennis (Diptera: Tephritidae) and Campiglossa loewiana (Diptera: Tephritidae) are phytophagous pests in China. Their damage has significantly impacted the collection and cultivation of germplasm resources of native Asteraceae plants. However, the genetic characteristics and structure of their population are unclear. This study focused on the highly damaging species of T. angustipennis and C. loewiana collected from the three-river source region (TRSR). We amplified the mitochondrial cytochrome C oxidase subunit I (mtCOI) gene sequences of these pests collected from this area and compared them with COI sequences from GenBank. We also analyzed their genetic diversity and structure. In T. angustipennis, 5 haplotypes were identified from 5 geographic locations; the genetic differentiation between France population FRPY (from Nylandia, Uusimaa) and China populations GLJZ (from Dehe Longwa Village, Maqin County), GLDR (from Zhique Village, Dari County), and GLMQ (from Rijin Village, Maqin County) was the strongest. GLJZ exhibited strong genetic differentiation from GLDR and GLMQ, with relatively low gene flow. For C. loewiana, 11 haplotypes were identified from 5 geographic locations; the genetic differentiation between the Chinese population GLMQ-YY (from Yangyu Forest Farm, Maqin County) and Finnish population FDNL (from Nylandia, Uusimaa) was the strongest, with relatively low gene flow, possibly due to geographical barriers in the Qinghai-Tibet plateau. Only 1 haplotype was identified across GLDR, GLMQ, and GLBM. High gene flow between distant locations indicates that human activities or wind dispersal may facilitate the dispersal of fruit flies and across different geographic. Geostatistical analysis suggested a recent population expansion of these 2 species in TRSR. Our findings provide technical references for identifying pests in the TRSR region and theoretical support for managing resistance, monitoring pest occurrences, analyzing environmental adaptability, and formulating biological control strategies for Tephritidae pests on Asteraceae plants.


Assuntos
Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons , Variação Genética , Tephritidae , Animais , Tephritidae/genética , China , Complexo IV da Cadeia de Transporte de Elétrons/genética , Haplótipos , Filogenia , Proteínas de Insetos/genética
2.
Sensors (Basel) ; 19(22)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726684

RESUMO

This paper explores the energy efficiency (EE) maximization problem in single-hop multiple-input multiple-output (MIMO) half-duplex wireless sensor networks (WSNs) with simultaneous wireless information and power transfer (SWIPT). Such an energy efficiency maximization problem is considered in two different scenarios, in which the number of energy-harvesting (EH) sensor nodes are different. In the scenario where the single energy-harvesting sensor node is applied, the modeled network consists of two multiple-antenna transceivers, of which the energy-constrained energy-harvesting sensor node harvests energy from the signals transmitted from the source by a power splitting (PS) scheme. In the scenario of multiple EH sensor nodes, K energy-constrained sensor nodes are applied and the same quantity of antennas are equiped on each of them. The optimization problem is formulated to maximize the energy efficiency by jointly designing the transceivers' precoding matrices and the PS factor of the energy-harvesting sensor node. The considered constraints are the required harvested energy, the transmission power limit and the requirement on the data rate. The joint design of the precoding matrices and the PS factor can be formulated as an optimization problem, which can be transformed into two sub-problems. An alternating algorithm based on Dinkelbach is proposed to solve the two sub-problems. The convergence of the proposed alternating algorithm, the solution optimality and the computational complexity are analyzed in the paper. Simulation results demonstrate the convergence and effectiveness of our proposed algorithm for realizing the maximum energy efficiency.

3.
J Plant Res ; 126(1): 63-72, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22688506

RESUMO

Seed rain is a crucial element in vegetation regeneration, but has been rarely studied in high altitude regions, particularly degraded Kobresia meadow. Weed infestation is a distinctive feature of pasture degradation in Kobresia meadows on the Tibetan plateau, the ecological mechanism of which is closely related with vegetation's seed rain. In this paper we assess the effect of vegetation degradation on seed rain and consider its implication for restoration of degraded Kobresia meadows in the headwater area of Yellow river, through analysis of seed species composition, number of seeds landing per m(2) of soil surface, and their relationship with above ground vegetation. Vegetation degradation had an impact on the species composition and numbers of seeds in seed rain and their relationship with above-ground vegetation. Within the un-degraded meadow, which provided a closed vegetation cover, 35 % of the seed rain was of sedge and gramineae species. However, within the degraded meadows, as the extent of degradation increased, so the total number of seeds m(-2) increased, with those derived from sedge and gramineae species forming a declining proportion of the total. Degradation of Kobresia meadow on the Tibetan plateau is exacerbated by the seed input of weed species (such as Oxytropis ochrocephala, Carum carvi, Aconitum pendulum, Pedicularis kansuensis in this study). Therefore, a major priority for the restoration of such degraded meadows should be the elimination of these weeds from the above ground vegetation by human intervention.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Cyperaceae/crescimento & desenvolvimento , Recuperação e Remediação Ambiental/métodos , Dispersão de Sementes , Ecossistema , Poluição Ambiental , Geografia , Plantas Daninhas , Solo , Tibet , Controle de Plantas Daninhas
4.
Environ Monit Assess ; 185(10): 8051-64, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23568012

RESUMO

Understanding the complex effects of biotic and abiotic factors on the composition of vegetation is very important for developing and implementing strategies for promoting sustainable grassland development. The vegetation-disturbance-environment relationship was examined in degraded alpine grasslands in the headwater areas of three rivers on the Qinghai-Tibet Plateau in this study. The investigated hypotheses were that (1) the heterogeneity of the vegetation of the alpine grassland is due to a combination of biotic and abiotic factors and that (2) at a small scale, biotic factors are more important for the distribution of alpine vegetation. On this basis, four transects were set along altitudinal gradients from 3,770 to 3,890 m on a sunny slope, and four parallel transects were set along altitudinal gradients on a shady slope in alpine grasslands in Guoluo Prefecture of Qinghai Province, China. It was found that biological disturbances were the major forces driving the spatial heterogeneity of the alpine grassland vegetation and abiotic factors were of secondary importance. Heavy grazing and intensive rat activity resulted in increases in unpalatable and poisonous weeds and decreased fine forages in the form of sedges, forbs, and grasses in the vegetation composition. Habitat degradation associated with biological disturbances significantly affected the spatial variation of the alpine grassland vegetation, i.e., more pioneer plants of poisonous or unpalatable weed species, such as Ligularia virgaurea and Euphorbia fischeriana, were found in bare patches. Environmental/abiotic factors were less important than biological disturbances in affecting the spatial distribution of the alpine grassland vegetation at a small scale. It was concluded that rat control and light grazing should be applied first in implementing restoration strategies. The primary vegetation in lightly grazed and less rat-damaged sites should be regarded as a reference for devising vegetation restoration measures in alpine pastoral regions.


Assuntos
Monitoramento Ambiental , Poluentes do Solo/análise , Altitude , Animais , China , Conservação dos Recursos Naturais , Ecossistema , Poaceae/crescimento & desenvolvimento , Ratos
5.
Ying Yong Sheng Tai Xue Bao ; 32(3): 869-877, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33754552

RESUMO

To clarify the variation of species composition, diversity, and functional structure of soil fungi community along alpine meadow degradation,we examined the characteristics and controlling factors of soil fungal communities in non-degraded, lightly degraded, moderately degraded, severely degraded and extremely degraded (black soil beach) alpine meadows at the Three Rivers Source Region, based on the high-throughput gene sequencing and FUNGuild functional prediction. The results showed that the dominant phyla in alpine meadow soil were Ascomycota, Basidiomycetes, and Mortierellomycota. Species composition of soil fungal community varied greatly in alpine meadow under different levels of degradation. The abundance of Cladosporium flabelliforme, Entoloma sodale, Hygrocybe conica, Inocybe sp. and Trichocladium opacum increased, while that of Gibberella tricincta and Dactylonectria macrodidyma decreased following grassland degradation. The meadow under severe degradation had higher soil fungal Chao1 index, while that under light degradation had lower Shannon index and Simpson index. The abundance of pathologic, symbiotic, and saprophytic types of fungi varied among different alpine meadows. Along with the grassland degradation, the abundance of soil symbiotic fungi decreased, while that of pathological fungi increased. The soil fungal community and functional compositions changed obviously with degradation in the alpine meadow. Plant aboveground biomass, soil water content, pH, total organic carbon, total nitrogen, ammonium nitrogen, available phosphate, total potassium and AN/AP (ratio of available nitrogen and available phosphorus) were the main driving factors for the variations in soil fungal community structure.


Assuntos
Micobioma , Solo , Agaricales , Ascomicetos , China , Cladosporium , Fusarium , Pradaria , Hypocreales , Nitrogênio/análise , Rios , Microbiologia do Solo
6.
World J Clin Cases ; 9(8): 1916-1922, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748242

RESUMO

BACKGROUND: The standard treatment of transitional cell carcinoma of the upper urinary tract consists of radical nephroureterectomy with bladder cuff removal, which can be performed either in open or laparoscopy or robot-assisted laparoscopy. Treatment of chronic renal insufficiency patients with upper urothelial tumor is in a dilemma. Urologists weigh and consider the balance between tumor control and effective renal function preservation. European Association of Urology guidelines recommend that select patients may benefit from endoscopic treatment, but laparoscopic treatment is rarely reported. CASE SUMMARY: In this case report, we describe a case of 79-year-old female diagnosed with urothelial carcinoma of the renal pelvis and adrenal adenoma with chronic renal insufficiency. The patient was treated with retroperitoneal laparoscopic partial resection of the renal pelvis and adrenal adenoma resection simultaneously. CONCLUSION: Retroperitoneal laparoscopic partial resection of the renal pelvis is an effective surgical procedure for the treatment of urothelial carcinoma of the renal pelvis.

7.
Nat Prod Res ; 26(13): 1234-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22017742

RESUMO

Eight phenanthrenes, 7-carboxy-2-hydroxy-1-methyl-5-vinyl-phenanthrene (1); 2,7-dihydroxy-1-methyl-5-aldehyde-9,10-dihydrophenanthrene (2); dehydroeffusol (3); dehydrojuncusol (4); 7-carboxy-2-hydroxy-1-methyl-5-vinyl-9,10-dihydrophenanthrene (5); 8-carboxy-2-hydroxy-1-methyl-5-vinyl-9,10-dihydrophenanthrene (6); effusol (7) and juncusol (8), were isolated from the aerial part of Juncus effusus. Compounds 1 and 2 were identified as new constituents. Compounds 7 and 8 showed anxiolytic and sedative activities.


Assuntos
Ansiolíticos/química , Ansiolíticos/farmacologia , Hipnóticos e Sedativos/química , Hipnóticos e Sedativos/farmacologia , Fenantrenos/química , Fenantrenos/farmacologia , Componentes Aéreos da Planta/química , Poaceae/química , Animais , Locomoção/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos
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