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Fahim Fawzia A. Fleita Daisy H. Ibrahim Abdallah M. El-Dars Farida M. S. 《Water, air, and soil pollution》2001,127(1-4):205-226
A fish canning facility processes 1900–2000 tons of mackerel and sardine annually at arate of 10–15 tons per day for a total of 200 days yr-1. This factory generates an average of 20 m3 of industrial wastewaters per day. The objective of our study, which was carried out on a bimonthly basisfrom December 1995 to November 1996, was to determine the overall pollutant load associated with this effluent in relation to the applicable Egyptian Standards and to propose methods for pollutant load reduction before discharging it to the local sewer. The methods were to benefit through the recovery of wasted organic load and transform it into an environmentally safe residue amenable for either immediate reuse or final disposal thereafter. Five chemical coagulation/flocculation treatments were tried using ferric chloride, alum, lime, ferric chloride and lime, and alum and lime. The best method involved the use of FeCl3 and Ca(OH)2 (0.4 g Fe L-1 and 0.2 g Ca L-1, respectively) which reduced the average influent BOD5 from 989 to 204 mg L-1, the COD from 1324 to 320 mg L-1, TSS from 4485 to 206 mg L-1, total protein content from 812 to 66 mg L-1 and oil and grease from 320 to 66 mg L-1. The separated dried precipitate averaged 50 g L-1 which was found to contain 40% by weight recovered protein and 20% recovered fat. The solid was ideal for on-site reprocessing as animal feed. As well, the final effluent, if not discharged to the area sewer, was safe for controlled use in some irrigation applications or forestry projects at the desert area surrounding the factory. 相似文献
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Vanrompay D Geens T Desplanques A Hoang TQ De Vos L Van Loock M Huyck E Mirry C Cox E 《Veterinary microbiology》2004,99(1):59-66
The prevalence of Chlamydiaceae infections on 258 closed pig breeding farms in Belgium was examined. For this purpose, 258 farms were randomly selected in the provinces West-Vlaanderen (44%), Oost-Vlaanderen (20%), Antwerpen (10%) and Vlaams-Brabant (6%). Of all farms examined, 96.5% were positive for Chlamydia-specific antibodies in ELISA and most were moderately to strongly positive. ELISA results revealed only 9 (3.5%) sero-negative farms. None of the ELISA negative sera reacted in immunoblotting. Only 212 of 249 ELISA positive sera reacted positive in immunoblotting. Additionally, 23 autopsy samples were examined by isolation in Vero cells. The major outer membrane sequence of the one isolate obtained showed 98.6% amino acid homology to the one of Chlamydophila psittaci strain CP3, formerly isolated from a pigeon. Present observations indicate that chlamydial infections are nearly endemic in the Belgian pig population and that Belgian pigs can become infected with C. psittaci. Nevertheless, the role and significance of Chlamydiaceae as pathogens in pigs remain unsolved and require further investigation. 相似文献
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ABSTRACT The exotic grass, Saccharum spontaneum L., has invaded abandoned agricultural lands in the Panama Canal Watershed for decades. The grass aggressively competes with regenerating tree seedlings preventing natural forest regeneration. To estimate effectual light level for controlling the grass, the growth of S. spontaneum was measured under a range of artificial shading conditions. Five shade treatment subplots–light intensities of 100% (full sunlight), 50, 25, 15, and 5%–were established at each of eight plots in land adjacent to the Panama Canal Watershed. Each site was cleared of S. spontaneum and then the regrowth was harvested. The regrowth of the grass was harvested and measured four times every one and half months for six months. The biomass of S. spontaneum was significantly less in lower light conditions than in full sunlight. The results showed that comparing growth of the grass at each harvest date, except for the first harvest date, there were significant differences between full sunlight and light intensities of 5, 15 and 25%. When compared by different harvest dates for each light level, only full sunlight showed a significant difference in biomass of the grass. The study demonstrates that shading is an effective method for controlling S. spontaneum. The results can be applied to developing reforestation strategies for abandoned lands occupied by S. spontaneum. 相似文献
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By enacting the Forest Rights Act 2006, the Government of India aimed to protect the rights of the forest dwellers; at the same time, it sought to involve the forest dwellers in protecting the forests. But the forest dwellers are critical of this Act, on the ground that it does not consider tribal customary laws, which are essential to protect both the forests and the rights of the forest dwellers. This paper examines the perceptions and attitudes of the dwellers of village forest and encroachers towards biodiversity conservation under the rights enshrined in the Forest Rights Act 2006. A survey was conducted in190 households in four village forests and two encroached villages under reserved forests of Sonitpur and Golaghat districts of Assam in Northeast India. The majority of the respondents were found to have positive attitudes towards environmental issues in general and protection of biodiversity loss in particular. Village-type, residents’ occupation, caste, source of fuel for cooking, educational qualifications and size of land holding were found to be significantly associated with attitudes towards biodiversity conservation. It is concluded that conducting an environmental education program and rights-holders’ monitoring system on the impact of their use of forest resources will support conservation of biodiversity. 相似文献
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Daisy Norgate Gert Ter Haar Nicola Kulendra Kata Orsolya Veres-Nyéki 《Veterinary anaesthesia and analgesia》2018,45(6):729-736
Objective
To compare the effect of propofol and alfaxalone on laryngeal motion under a light plane of anaesthesia in nonbrachycephalic and brachycephalic dogs anaesthetized for nonemergency procedures.Study design
Prospective, randomized clinical trial.Animals
A total of 48 client-owned dogs (24 nonbrachycephalic and 24 brachycephalic).Methods
A standardized premedication of methadone (0.2 mg kg?1) and acepromazine (0.01 mg kg?1) was administered intramuscularly. Dogs were randomly assigned to be induced with increments of propofol (1–4 mg kg?1) or alfaxalone (0.5–2 mg kg?1). Laryngeal assessment was performed under a light plane of anaesthesia by a surgeon (GTH) who was unaware of the induction protocol. Laryngeal movement was assessed as either being present when abduction of the laryngeal cartilages upon inspiration was identified, or absent when abduction was not recognized. Simultaneously, a 60-second video was recorded. The same surgeon (GTH) and an additional surgeon (NK) re-evaluated the videos 1 month later. Categorical comparisons were studied using Chi square and Fisher’s exact test where appropriate. Pairwise evaluation of agreement between scorers was undertaken with the kappa statistic (κ).Results
There were no significant differences (p > 0.05) identified between the presence or absence of laryngeal motion between dogs administered propofol or alfaxalone, as well as when analysing nonbrachycephalic and brachycephalic dogs separately. The majority of dogs (>75%) maintained some degree of laryngeal motion with both protocols. Agreement between assessors was excellent (κ = 0.822).Conclusions
Alfaxalone maintained laryngeal motion similarly to propofol in nonbrachycephalic and brachycephalic dogs.Clinical relevance
Both agents would appear appropriate for allowing assessment of laryngeal motion in nonbrachycephalic and brachycephalic dogs. The assessment technique of subjective evaluation of laryngeal motion via peroral laryngoscopy under a light plane of anaesthesia produced consistent results amongst assessors, regardless of the induction agent used. 相似文献8.
Deforestation and degradation of tropical old-growth forests has the potential to cause catastrophic species extinctions. In this review, we assess whether regenerating secondary forests (SF) can support species typically found in old-growth forest (OG) and so prevent extinctions. We review 65 studies that compare faunal diversity in SF and corresponding OG, and compare the similarity of species composition both within and between these two forest types using the Sorensen, Morisita-Horn and Sorensen-Chao indices. Comparisons between traditional similarity indices and Sorensen-Chao, which minimizes sampling biases, indicated that limited sampling effort consistently reduced apparent similarity between SF and OG and that similarity between SF and OG is actually higher than previously appreciated. Similarity, which ranges from 0 to 1, varied from 0.49 to 0.92 between replicate OG sites and was correlated with similarity between SF and OG. This correlation might be an artefact of variation among studies in sampling effort, especially for vertebrates where small samples reduce apparent similarity across all comparisons, as well as a real effect of variation among studies in landscape heterogeneity and the presence of species with patchy distributions. Therefore, similarity between SF and OG cannot be interpreted without an understanding of background variation in OG. Similarity between different SF sites provided no evidence that disturbance specialists dominate SF. Similarity to OG increased rapidly with SF age; when SF was contiguous with OG; when SF was growing in small clearings; and after low intensity land uses including clearing only, shifting agriculture and tree plantations. This describes the most frequently observed tropical SF; isolated from roads and on hilly terrain unsuitable for mechanized agriculture. Thus, our analyses indicate that tropical SF can play an important role in biodiversity conservation particularly when OG forests are nearby. An important caveat remains, however. Abundance, geographic range and levels of habitat specialization are often related. Widespread, abundant, habitat generalists might dominate similarity analyses even when relatively rare OG specialists are present. Additional species-level analyses of habitat specialization will be needed before the conservation value of tropical SF is fully understood. 相似文献
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Laroucau K de Barbeyrac B Vorimore F Clerc M Bertin C Harkinezhad T Verminnen K Obeniche F Capek I Bébéar C Durand B Zanella G Vanrompay D Garin-Bastuji B Sachse K 《Veterinary microbiology》2009,135(1-2):82-89
Five severe cases of psittacosis in individuals associated with duck farms were notified in France between January and March 2006. Diagnostic examination included serology and/or molecular detection by PCR from respiratory samples. As a consequence, we investigated all duck flocks (n=11) that were housed in the three farms where human infections occurred. While serology by complement fixation test was negative for all samples, cloacal and/or tracheal chlamydial excretion was detected by PCR in all three units. Notably, one duck flock was tested strongly positive in 2 of the 3 affected farms, and Chlamydophila (C.) psittaci strains were isolated from cloacal and/or tracheal swab samples from both farms. Human samples and duck isolates exhibited the same PCR-RFLP restriction pattern, which appeared to be an intermediate between genotypes A and B. Analysis of ompA gene sequences and comparison to those of the type strains showed that the isolates could not be strictly assigned to any of the generally accepted genotypes of C. psittaci. Further analysis by MLVA of the PCR-positive human samples revealed two distinct patterns, which were related to previously isolated C. psittaci duck strains. 相似文献
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Claudia Torres-Calzada Raul Tapia-Tussell Inocencio Higuera-Ciapara Daisy Perez-Brito 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(1):67-79
Recently, anthracnose has become a major problem in papaya production and postharvest stages. The occurrence of both Colletotrichum gloeosporioides and Colletotrichum capsici has been demonstrated in this crop. The differential response of these pathogens to fungicides has highlighted the need to use rapid and accurate techniques to identify them. Thus, the objective of this study was to reveal the genetic diversity of Colletotrichum isolates in Mexican papaya fields. C. gloeosporioides-and C. capsici-specific primers were successfully used to detect the pathogens from different papaya parts. A combination of morphological characters, molecular techniques and pathogenicity tests were used to characterize 37 isolates from different localities of five papaya-producing states. Analyses of the 5.8-ITS region and arbitrarily primed-PCR revealed intraspecific groups; most of the isolates within these groups have the same geographical location and morphological characteristics. Knowledge of the genetic diversity of Colletotrichum spp. in Mexican papaya fields will facilitate the identification of the pathogen population in this crop in order to select the appropriate fungicide to control anthracnose, as well as to improve genetic resistance breeding programs. 相似文献