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1.
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Indigenous ecological knowledge (IEK) can contribute to the management of local ecosystems and landscapes. Cultural landscapes are produced by and reflect the long-term interactions between humans and nature in indigenous societies. Yunnan Province, located in southwestern China, is the homeland of many ethnic groups, and is also a refuge for numerous species of wild plants and animals. Indigenous people in Yunnan, who have rich ecological knowledge, play an important role in the conservation of local biodiversity and the region’s unique terraced agricultural landscapes. We used the Hani people and their outstanding cultural landscape of rice terraces in Yuanyang County of Yunnan Province as a case study to describe their worldview and discuss their formation of IEK; their roles in the preservation of rice landraces and in pest regulation; their management of water, forest, and soil resources; and the vertical landscape pattern and resource-circulation system that has evolved in the areas managed by the Hani. We also discuss the challenges and threats facing the Hani, their IEK, and their cultural landscape, as well as discuss the potential for integration of the Hani’s IEK with modern conservation efforts.  相似文献   

3.
Drawing on the growing literature on Muslim women’s activism, this paper explores grammars of action that frame political mobilizations of Muslim women in the UK. By taking a broad view of political activism, we identify acts and practices of citizenship through which Muslim women activists engage with, reinterpret and challenge social norms. The article critically engages with dominant readings of post-migration minorities’ political mobilization through the lens of citizenship regimes and draws attention to more processual and agency-centred perspectives on citizenship. We focus on two salient themes that Bristol-based Muslim activists were concerned with: mobilizing against violence against women, manifested in the anti-FGM campaign by Integrate Bristol, and attempts to re-negotiate the terms of participation in religious spaces, manifested in claims for more inclusive mosques. In both instances, mobilization was not confined to the local community or national level, but supported by and embedded in related transnational struggles.  相似文献   

4.
International Microbiology - In the field of observational and experimental natural sciences (as is the case for microbiology), recent decades have been overinfluenced by overwhelming technological...  相似文献   

5.
In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug.  相似文献   

6.
β-D-Galactosidase was purified 115-fold from a saline extract of papaya seeds by fractionation with ammonium sulfate, DEAE-Sephadex chromatography and gel-filtration on Sephadex G-75, G-150, and G-100. The purified β-D-galactosidase (MW, 56,000 daltons) had an isoelectric point (pI) at pH 8.4 and the optimal pH for its activity was 3.5 to 4.5. The enzyme activity was inhibited by Cu2+,Ag+,Hg2+,Pb2+,NaAsO2 and р-chloromercuribenzoate at concentrations of 1x10-3 M. Among the various mono- and oligosaccharides tested, D-galactose, D-galacturonic acid, D-galactono-γ-lactone and melibiose significantly inhibited the enzyme activities at concentrations of 2xl0-3 to 1X10-2M. The purified enzyme hydrolyzed β-nitrophenyl β-D-galactoside (Km = 1.0X10-3M), methyl β-D-galactoside (Km=1.6x10-2M), aminoethyl β-D-galactoside (Km =3.3X10-2M) and lactose (Km = 9.1X10-2M). β-(l→3)-Linked galactotetraosyl-eryth itol and asialo-glycopeptide isolated from fetuin were also hydrolyzed to the extent of 78 and 75%, 4respectively, on the basis of their galactose contents.

∝-D-Mannosidase from papaya seeds was also purified 130-fold by ammonium sulfate fractionation, DEAE-Sephadex chromatography, gel-filtration on Sephadex G-150 and hydroxylapatite chromatography. The purified enzyme (MW, 156,000 daltons), consisting of two subunits (78,000x2), was inhibited by Hg2+,Ag+,Cu2+, р-chloromercuribenzoate, D-glucose, D-glucosamine and D-mannose at concentrations of lx10-3 to 1x10-2M. The ∝-D-mannosidase hydrolyzed р-nitrophenyl ∝-D-mannoside (Km=5.6x10-3M), methyl ∝-D-mannoside (Km=2.8X10-2M), ∝-D-mannosyl-D-mannitol (Km=2.2X10-2M), ∝-(l→2)linked D-mannobiosyl-D-mannitol (Km=6.3x10-3M) and D-mannotriosyl-D-mannitol (Km=5.3x10-3 M).  相似文献   

7.
The brown planthopper, Nilaparvata lugens (Stål) is an important pest in rice. It has been widely recognized that the juvenile hormone (JH) is regulated by its hydrolase, which includes juvenile hormone esterase (JHE), juvenile hormone epoxide hydrolase (JHEH) and juvenile hormone diol kinase (JHDK). In this paper, we cloned the gene of Jhdk and the gene expression at different stages of N. lugens was analysed, and the relationship with Jhe and Jheh was studied after silencing the jhdk gene of N. lugens (Nljhdk) through double-stranded RNA (dsRNA) feeding. We also explored the expression of the three JH hydrolase after indoxacarb treatments. RT-PCR was used to amplify the full length Jhdk cDNA, and the Nljhdk gene was expressed throughout all the development periods tested and showed the lowest level at the 4th instar and the highest in the 5th instar. The expression level of Nljhdk in male adults was higher than that of female adults. Through feeding, dsRNA against Nljhdk successfully knocked down the target gene, which had no significant effect on the expression of the jhe gene of N. lugens (Nljhe), while the expression of Nljheh was upregulated. Indoxacarb could inhibit N. lugens reproduction, and the expression level of Nljhe and Nljhdk increased with the increasing of indoxacarb concentration, but the expression of the jheh gene of N. lugens (Nljheh) was reduced. These studies provide a line of experimental evidence in N. lugens to support that Nljhdk encodes the functional protein involved in JH degradation and further showed the relationship of the three hydrolases and the mechanism of indoxacarb inhibition of the fecundity of N. lugens.  相似文献   

8.
A hallmark of regulatory B cells is IL-10 production, hence their designation as IL-10+ B cells. Little is known about the ability of self-antigens to induce IL-10+ B cells in Graves’ disease (GD), Hashimoto’s thyroiditis (HT), or other autoimmune disease. Here we pulsed purified B cells from 12 HT patients, 12 GD patients, and 12 healthy donors with the thyroid self-antigen, thyroglobulin (TG) and added the B cells back to the remaining peripheral blood mononuclear cells (PBMCs). This procedure induced IL-10+ B-cell differentiation in GD. A similar tendency was observed in healthy donors, but not in cells from patients with HT. In GD, B cells primed with TG induced IL-10-producing CD4+ T cells. To assess the maximal frequency of inducible IL-10+ B cells in the three donor groups PBMCs were stimulated with PMA/ionomycin. The resulting IL-10+ B-cell frequency was similar in the three groups and correlated with free T3 levels in GD patients. IL-10+ B cells from both patient groups displayed CD25 or TIM-1 more frequently than did those from healthy donors. B-cell expression of two surface marker combinations previously associated with regulatory B-cell functions, CD24hiCD38hi and CD27+CD43+, did not differ between patients and healthy donors. In conclusion, our findings indicate that autoimmune thyroiditis is not associated with reduced frequency of IL-10+ B cells. These results do not rule out regulatory B-cell dysfunction, however. The observed phenotypic differences between IL-10+ B cells from patients and healthy donors are discussed.  相似文献   

9.
Pigment-based coloration is a common trait found in a variety of organisms across the tree of life. For example, calcareous avian eggs are natural structures that vary greatly in color, yet just a handful of tetrapyrrole pigment compounds are responsible for generating this myriad of colors. To fully understand the diversity and constraints shaping nature’s palette, it is imperative to characterize the similarities and differences in the types of compounds involved in color production across diverse lineages. Pigment composition was investigated in eggshells of eleven paleognath bird taxa, covering several extinct and extant lineages, and shells of four extant species of mollusks. Birds and mollusks are two distantly related, calcareous shell-building groups, thus characterization of pigments in their calcareous structures would provide insights to whether similar compounds are found in different phyla (Chordata and Mollusca). An ethylenediaminetetraacetic acid (EDTA) extraction protocol was used to analyze the presence and concentration of biliverdin and protoporphyrin, two known and ubiquitous tetrapyrrole avian eggshell pigments, in all avian and molluscan samples. Biliverdin was solely detected in birds, including the colorful eggshells of four tinamou species. In contrast, protoporphyrin was detected in both the eggshells of several avian species and in the shells of all mollusks. These findings support previous hypotheses about the ubiquitous deposition of tetrapyrroles in the eggshells of various bird lineages and provide evidence for its presence also across distantly related animal taxa.  相似文献   

10.
Although density-dependent benefits to hemipterans from ant tending have been measured many times, few studies have focused on integrated effects such as interactions between ant tending, natural enemy density, and hemipteran density. In this study, we tested whether the invasive mealybug Phenacoccus solenopsis is affected by tending by ghost ants (Tapinoma melanocephalum), the presence of parasitoids, mealybug density, parasitoid density and interactions among these factors. Our results showed that mealybug colony growth rate and percentage parasitism were significantly affected by ant tending, parasitoid presence, and initial mealybug density separately. However, there were no interactions among the independent factors. There were also no significant interactions between ant tending and parasitoid density on either mealybug colony growth rate or percentage parasitism. Mealybug colony growth rate showed a negative linear relationship with initial mealybug density but a positive linear relationship with the level of ant tending. These results suggest that benefits to mealybugs are density-independent and are affected by ant tending level.  相似文献   

11.
It is hypothesised here that some mealybug (Pseudococcidae) and root mealybug (Rhizoecidae) prepupae and pupae are mobile. The prepupa and pupa of the mealybug Promyrmococcus dilli Williams and the prepupa of the root mealybug Ripersiella malschae (Williams) are described and illustrated and their probable mobility is discussed. It is also suggested that the prepupae and pupae of the mealybug Macrocepicoccus loranthi Morrison can move rapidly on the leaves when disturbed.  相似文献   

12.
The aim of this work was to compare three methods to determinate low concentrations of Paracoccus denitrificans encapsulated in polyvinyl alcohol pellets, which is important for evaluation and optimization of pellet production as well as for monitoring of biomass growth. Pellets with different and well-defined biomass concentrations were used for experiments. The following fast and simple methods were tested: (1) dissolution of polyvinyl alcohol in hot water followed by dry weight estimation, (2) dissolution of polyvinyl alcohol in hot water followed by optical density measurement, (3) and extraction and quantification of proteins. Dry weight estimation proved to be problematic as it was difficult to separate biomass from polymeric carrier. Optical density measurement showed good linearity of dependence of optical density on biomass content, but determined limits of detection and limits of quantification were not within the range necessary for intended application. The only tested method meeting the requirements for sensitivity was determination of protein concentration after protein extraction.  相似文献   

13.
Previous studies performed in France have suggested that handling hay contaminated with high amounts of moulds, and especially Absidia corymbifera and Eurotium amstelodami, may favour farmer’s lung disease. The circumstances favouring farmer’s lung disease and the distinctive microbiological composition of hay samples that provoke attacks need to be specified. We present a case–control study which investigates the agricultural practices and the microbiological composition of hay handled in patients with farmer’s lung disease as compared to those of a representative control population. Ten cases identified the hay they were handling at the onset of symptoms. The location, type of farm and working conditions were similar to those of the control farms. Conversely, the microbiological composition of hay differed, with significantly higher amounts of E. amstelodami (P < 0.01), A. corymbifera (P = 0.003), mesophilic Streptomyces (P < 0.01), thermophilic Streptomyces (P < 0.01) and Saccharomonospora viridis (P < 0.01) than in the control population. Our results demonstrate that hay identified by patients as having a harmful effect is characterized by a higher total amount of microorganisms, notably five microorganisms that seem discriminative. Mean concentrations are 2- to 115-fold higher in hay suspected to cause symptoms than in hay from a representative panel of farms. Handling hay with high amounts of these five microorganisms constitutes a risk factor for farmer’s lung disease that should be considered for the development of prophylactic measures.  相似文献   

14.
Interstitial cells of Cajal (ICC) are critical to gastrointestinal motility. The phenotypes of ICC progenitors have been observed in the mouse gut, but whether they exist in the human colon and what abnormal changes in their quantity and ultrastructure are present in Hirschsprung’s disease (HSCR) colon remains uncertain. In this study, we collected the surgical resection of colons, both proximal and narrow segments, from HSCR patients and normal controls. First, we identified the progenitor of ICC in normal adult colon using immunofluorescent localization techniques with laser confocal microscopy. Next, the progenitors were sorted to observe their morphology. We further applied flow cytometry to examine the content of ICC progenitors in these fresh samples. The ultrastructural changes in the narrow and proximal parts of the HSCR colon were observed using transmission electron microscopy (TEM) and were compared with the normal adult colon. The presumed early progenitor (c-KitlowCD34+Igf1r+) and committed progenitor (c-Kit+CD34+Igf1r+) of ICC exist in adult normal colon as well as in the narrow and proximal parts of the HSCR colon. However, the proportions of mature, early and committed progenitors of ICC were dramatically reduced in the narrow segment of the HSCR colon. The proportions of mature and committed progenitors of ICC in the proximal segment of the HSCR colon were lower than in the adult normal colon. Ultrastructurally, ICC, enteric nerves, and smooth muscle in the narrow segment of the HSCR colon showed severe injury, including swollen vacuola or ted mitochondria, disappearance of mitochondrial cristae, dilated rough endoplasmic reticulum, vesiculation and degranulation, and disappearance of the caveolae on the ICC membrane surface. The contents of ICC and its progenitors in the narrow part of the HSCR colon were significantly decreased than those of adult colon, which may be associated with HSCR pathogenesis.  相似文献   

15.
In Iowa, the management of insect pests in soybean, Glycine max (L.) Merr., has been complicated by the arrival of the invasive species soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), and occasional outbreaks of bean leaf beetle, Cerotoma trifurcata (F?rster) (Coleoptera: Chrysomelidae), populations leading to economic losses. Several insecticide programs designed to reduce abundance of the overwintered and first generation C. trifurcata and the incidence of bean pod mottle virus were evaluated over 3 yr (2004-2006) for their impacts on A. glycines populations, at three locations in Iowa (Floyd, Lucas, and Story counties). There was no significant overlap of either overwintered (early May) or the first (early July) generations of C. trifurcata with A. glycines, because aphids were first detected in June and they did not reach economically damaging levels until August, if at all. During this study, insecticides targeting the overwintered population or the first generation of C. trifurcata provided a limited impact on A. glycines populations compared with untreated controls, and they did not prevent economic populations from occurring. Furthermore, the highest populations of A. glycines were frequently observed when a low rate of lambda-cyhalothrin (178 ml/ha) was applied targeting the overwintered population of C. trifurcata. Soybean yields were not protected by any of the insecticide treatments. Our results indicate that the use of either early season foliar or seed-applied insecticides for C. trifurcata management is of limited value for A. glycines management.  相似文献   

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Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.  相似文献   

18.
BackgroundMen’s involvement in reproductive health is recommended. Their involvement in antenatal care service is identified as important in maternal health. Awareness of obstetric danger signs facilitates men in making a joint decision with their partners regarding accessing antenatal and delivery care. This study aims to assess the level of knowledge of obstetric complications among men in a rural community in Tanzania, and to determine their involvement in birth preparedness and complication readiness.MethodsA cross-sectional survey was conducted where 756 recent fathers were invited through a two-stage cluster sampling procedure. A structured questionnaire was used to collect socio-demographic characteristics, knowledge of danger signs and steps taken on birth preparedness and complication readiness. Data were analyzed using bivariate and multivariable logistic regression to determine factors associated with being prepared, with statistically significant level at p<0.05.ResultsAmong the invited men, 95.9% agreed to participate in the community survey. Fifty-three percent could mention at least one danger sign during pregnancy, 43.9% during delivery and 34.6% during the postpartum period. Regarding birth preparedness and complication readiness, 54.3% had bought birth kit, 47.2% saved money, 10.2% identified transport, 0.8% identified skilled attendant. In general, only 12% of men were prepared. Birth preparedness was associated with knowledge of danger signs during pregnancy (AOR = 1.4, 95% CI: 1.8-2.6). It was less likely for men living in the rural area to be prepared (AOR=0.6, 95% CI; 0.5-0.8).ConclusionThere was a low level of knowledge of obstetric danger signs among men in a rural district in Tanzania. A very small proportion of men had prepared for childbirth and complication readiness. There was no effect of knowledge of danger signs during childbirth and postpartum period on being prepared. Innovative strategies that increase awareness of danger signs as well as birth preparedness and complication readiness among men are required. Strengthening counseling during antenatal care services that involve men together with partners is recommended.  相似文献   

19.
Management and sustainability of fisheries has been guided by theories and models derived from modern ecological science. Traditional ecological knowledge (TEK) has been ignored in all spheres of decision-making for management and sustainability of fisheries in East Africa. TEK guided African communities in the way they associated and interacted with the natural environment around them. Spiritual rituals, religious practices, social taboos and sacred animal totems guided the peoples on how and when to utilize the available natural resources. In the advent of modern scientific knowledge, the African traditional knowledge quickly faded away and is generally seen as irrelevant. Today the potential of TEK in the management and sustainability of fisheries in East Africa has not been realized and its status and future is unknown. TEK should be complementary to modern scientific knowledge in the management and sustainability of fisheries. This paper therefore focuses on the potential application of TEK in the management and sustainability of fisheries in East Africa and the issues that impede its application.  相似文献   

20.
Triatoma infestans (Klug) is the main vector of Chagas’ disease in the Southern Cone of Latin America between the latitudes 10° S and 46° S. The long-term effectiveness of the control campaigns is greatly dependent upon the vector population structure. Mitochondrial DNA (mtDNA) genes have been used in a number of T. infestans population genetic analyses. However, the maternally inherited markers as well as nuclear ribosomal DNA analyzed until the present exhibited low or limited levels of variation. Analyses based on microsatellite markers strongly supported the existence of some type of stratification in T. infestans populations and supported the hypothesis of vector population recovery from survivors of the insecticide-treated areas, highlighting the value of population genetic analyses in assessing the effectiveness of Chagas’ disease vector control programmes. Although phylogeographic studies have generally suggested a Bolivian Andean origin of T. infestans, they recovered two reciprocal monophyletic groups of T. infestans and Bolivian populations who were not basal as expected for an ancestral group. In addition, a non-Andean origin could not be excluded by mtDNA genealogies that included sylvatic bugs from Gran Chaco. On the other side, mitochondrial and microsatellite markers supported the hypothesis of two independent migration events of colonization and secondary contacts in southern South America. Since the phylogenetic analyses remain inconclusive, more sequences, not only from mitochondrial genes but also from nuclear genes, need to be examined.  相似文献   

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