428 research outputs found
Urban and Rural—Population and Energy Consumption Dynamics in Local Authorities within England and Wales
The formulation of feasible and pragmatic policies that mitigate climate change would require a thorough understanding of the interconnectivity that exists between environment, energy, and the composition of our settlements both urban and rural. This study explores the patterns of energy consumption in England and Wales by investigating consumption behavior within domestic and transport sectors as a function of city characteristics, such as population, density, and density distribution for 346 Local Authority Units (LAU). Patterns observed linking energetic behavior of these LAUs to their respective population and area characteristics highlight some distinctly contrasting consumption behaviors within urban and rural zones. This provides an overview of the correlation between urban/rural status, population, and energy consumption and highlights points of interest for further research and policy intervention. The findings show that energy consumption across cities follows common power law scaling increasing sub-linearly with their population regardless of their urban/rural classification. However, when considering per capita and sector specific consumptions, decreasing per capita consumption patterns are observed for growing population densities within more uniformly populated urban LAUs. This is while rural and sparsely populated LAUs exhibit sharply different patterns for gas, electricity, and transport per capita consumption
Productivity, infrastructure, and urban density – an allometric comparison of three European city-regions across scales
Agglomeration-based arguments citing Dutch and German city-regions have been a primary driver in advocating intercity transport strategies in the north of England. In this paper, we adopt an allometric urban model investigating the applicability and transferability of these transport-led agglomerative strategies promoted to address England’s regional economic under-performance. This is undertaken through a comparative study of the size-cost performance balance of three city-regions and the overall urban networks in the Netherlands, Germany, and England and Wales using city units defined at different spatial scales. While our results support a case for better mobility and transport comparing the three urban networks regardless of the spatial scales, comparisons of specific city-regions indicate a more nuanced interplay of productivity, mobility infrastructure, and urban density
Molecular detection of Trichostrongylus species through PCR followed by high resolution melt analysis of ITS-2 rDNA sequences
Polymerase chain reaction followed by high resolution melting (PCR-HRM) analysis is a simple, rapid and accurate method for molecular detection of various nematode species. The objective of the present study was, for the first time, to develop a PCR-HRM assay for the detection of various animal Trichostrongylus spp. A pair of primers targeting the ITS-2 rDNA region of the Trichostrongylus spp. was designed for the development of the HRM assay. DNA samples were extracted from 30 adult worms of Trichostrongylus spp., the ITS-2-rDNA region was amplified using PCR, and the resultant products were sequenced and characterized. Afterwards, the PCR-HRM analysis was conducted to detect and discriminate Trichostrongylus spp. Molecular sequence analysis revealed that 24, 4, and 1 of the samples were T. colubriformis, T. vitrinus and T. capricola, respectively. Results from PCR-HRM indicated that complete agreement was relatively found between speciation by HRM analysis and DNA sequencing for the detection of Trichostrongylus species. The PCR-HRM analysis method developed in the present study is fast and low-cost; the method can be comparable with other molecular detection techniques, representing a reliable tool for the identification of various species within the Trichostrongylus genus. © 2020 Elsevier B.V
Molecular identification of Sarcocystis species in raw hamburgers using PCR–RFLP method in Kashan, central Iran
The prevalence of bovine Sarcocystosis is high in the most regions of the world. It can be a human health problem due to consumption of raw or under cooked hamburgers or other bovine meat products. This study was carried out to investigate the prevalence and species identification of Sarcocystis among of hamburgers, using PCR–RFLP methods in Kashan, central Iran. Overall 200 raw industrial hamburgers samples with at least 60% meat were randomly collected from nine different brands in Kashan, central Iran. The genomic DNA was extracted and a PCR–RFLP method was used to amplify an approximately 900 bp fragment at the 18S rRNA(SSU) gene, restriction enzyme BclI was used for species identification. The results showed that 58 (29%) of 200 tested hamburger samples were infected to Sarcocystis spp. The prevalence rate was 31.25 and 26.9% in the hamburgers with 90 and 60–75% meat, respectively. According to PCR–RFLP analysis, 43 (74.1%) of the 58 isolates were Sarcocystis cruzi, 12 (20.7%) showed co-infection to S. cruzi and Sarcocystis hirsuta, 2 (3.5%) was mixed infected to S. cruzi and Sarcocystis hominis, 1 (1.7%) showed the pattern of mix infection to three species. This study revealed one-third of industrial hamburger were infected to S. cruzi or mixed infection of S. cruzi with other bovine sarcocytosis. To prevent cattle infection, the possible ingestion of the disposal sporocyst stage from dogs must be eliminated. Although in this study, the prevalence of S. hominis was low and cannot be considered as a major zoonosis, it should be recommended avoiding eating under cooked hamburger and other bovine meat products to prevent human infection
Genetic variation of Giardia lamblia isolates from food-handlers in Kashan, Central Iran
<p><strong><em>Background:</em></strong> Based on genotyping study of human isolates of <em>Giardia lamblia</em>; humans are mainly infected by two assemblages A and B. The present study was carried out to determine the sub-assemblages of <em>G. lamblia</em> isolated from food handlers referred to Kashan health centers, central Iran, 2015.</p><p><strong><em>Methods:</em></strong> In this cross-sectional<strong> </strong>study,<strong> </strong>3653 stool samples collected from food-handlers that annually refer to health center for getting a health certification and examined microscopically for <em>G. lamblia</em> cyst. Totally, 44 isolates were selected from 47 <em>Giardia</em> positive samples. Cysts were partially purified by the sucrose density gradient method. After freeze-thaw cycles, genomic DNA was extracted using QIAamp Stool Mini kit. A single step PCR-RFLP method was used to amplify a 458bp fragment at the glutamate dehydrogenase <em>(gdh</em>) locus, restriction enzymes <em>BspLI </em>and <em>RsaI</em> were used for distinguish between genotypes A and B and their subgroups.</p><p><strong><em>Results:</em></strong> Of 44 isolates, 24(54.5%) were sub-assemblage AII, 9(20.5%) group B including 7(15.9%) BIII and 2(4.6%) BIV sub-assemblage and 11(25%) isolates showed a mixed pattern of AII and B. Sub-assemblage AI was not detected in this study.</p><strong><em>Conclusion:</em></strong> The higher rate of sub-assemblage AII demonstrated an anthroponotic origin of the infection so infected food-handlers could directly transmit this protozoan to consumers via contaminated food and water. For finding of pattern of transmission and distribution of <em>Giardia</em> assemblages and sub-assemblage, more studies in human and animal population in different regions are necessary
Induction of apoptosis by alcoholic extract of combination verbascum thapsus and ginger officinale on Iranian isolate of trichomonas vaginalis
Introduction: The genus Malassezia is an important skin resident of human. The present study aimed to analyze in vitro activity of the essential oils of Lavandula stoechas, Cuminum cyminum and Artemisia sieberi against clinical strains of Malassezia species. Methods: A total of 47 Malassezia strains, including Malassezia furfur, Malassezia globosa and Malassezia obtuse, were used in this study. A disk diffusion technique was selected for testing the susceptibility of Malassezia strains to the essential oils. Results: All the essential oils showed in vitro activity against Malassezia strains, with M. furfur and M. obtusa being the highest and lowest susceptible of the strains, respectively. The highest antifungal activity was associated with the essential oil of C. cyminum (mean ± SD: 50.0 ± 0.0 mm), followed by L. stoechas (mean ± SD: 46.8 ± 3.1 mm) and A. sieberi (mean ± SD: 36.9 ± 5.7 mm). The inhibition zone ranges were 12.5 to 15.6 mm (mean ± SD: 14.4 ± 1.6 mm) for ketoconazole and 11.6 to 13.3 mm (mean ± SD: 12.4 ± 0.9 mm) for fluconazole. Although all the antifungal drugs were found to possess good antifungal activities against Malassezia strains, their effects were lower than the activities shown by the essential oils tested (P < 0.05). Conclusion: These results indicated that the essential oils tested, especially the one from C. cyminum, inhibited the growth of clinical strains of Malassezia, implying its potential use in the treatment of Malassezia infections. This indicates that this plant may be useful in preparation of new drugs
The effect of alcoholic extracts of Arctium lappa L. and Satureja hortensis L. against Trichomonas vaginalis in vitro
Background: Trichomonas vaginalis infection is one of the most prevalent type of vaginitis in women. Considering the side effects of metronidazole and therapeutic properties of Arctium lappa L. and Satureja hortensis L. in traditional medicine, this study aimed to examine the anti-Trichomonas effects of Arctium lappa and Satureja hortensis alcoholic extracts in vitro.
Materials and Methods: This experimental study was conducted on T. vaginalis isolated from 1203 persons referred to five health centers in Kashan city. Five T. vaginalis isolates were cultured in a TYI-S-33 medium and were used to study the effect of Arctium lappa and Satureja hortensis extracts. The effects of different concentrations (12.5, 25, 50, 100, 200, 400, 800 and 1000 µg/mL) of plant extracts on the growth of T. vaginalis trophozoeites were studied 12, 24, and 48 h after the culture. Also, the culture media and metronidazole (0.025, 0.05, 0.1, 0.2, 0.4 µg/mL) were considered as the negative and positive controls, respectively. The effects of the extracts and drug were examined by counting the number of live and dead parasites using the trypan blue staining method.
Results: Results showed that the alcoholic extracts of Satureja hortensis and Arctium lappa had an inhibitory effect on the growth of T. vaginalis. The IC50 values of the alcoholic extracts of Satureja hortensis, Arctium lappa and metronidazole after 24 h were 190.8, 996.7 and 0.0326 µg/mL, respectively.
Conclusion: The present study shows the in vitro anti-Trichomonas effect of Arctium lappa and Satureja hortensis extracts. The anti-Trichomonas effect of Satureja hortensis extract was higher than that of the Arctium lappa extract. Further studies are recommended to investigate the anti-Trichomonas effect of major components of these plants, especially the Satureja hortensis extract
Power-law Parameterized Quintessence Model
We introduce a power-law parameterized quintessence model for the dark energy
which accelerate universe at the low redshifts while behaves as an ordinary
matter for the early universe. We construct a unique scalar potential for this
parameterized quintessence model. As the observational test, the Supernova Type
Ia (SNIa) Gold sample data, size of baryonic acoustic peak from Sloan Digital
Sky Survey (SDSS), the position of the acoustic peak from the CMB observations
and structure formation from the 2dFGRS survey are used to constrain the
parameters of the quintessence model. The best fit parameters indicates that
the equation of state of this model at the present time is less than one
which violates the energy condition in General Relativity. Finally
we compare the age of old objects with age of universe in this model.Comment: 11 pages, 17 figures, submitted to Phys. Rev.
Comments on ‘A multi-level framework for metabolism in urban energy systems from an ecological perspective’ by Pulido Barrera et al. (2018)
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