Petroleum refinery secondary effluent polishing using freezing processes--toxicity and organic contaminant removal

A petroleum refinery secondary effluent was treated using two freezing techniques--spray freezing and unidirectional downward freezing (UDF). The freezing processes were effective to remove toxicity and total organic carbon (TOC)- and chemical oxygen demand (COD)-causing materials in the effluent. Agitation of the liquid during UDF significantly improved the impurity separation efficiency; 85 to 96% removal of TOC and COD was achieved without any pretreatment and freezing only 70% of the feed water. The treatment efficiency of the spray freezing was at the same level as that of UDF without mixing. The spray ice with longer storage time released more contaminants with early meltwater. The initial contaminant concentration of the feed water and the freezing temperatures (-10 degrees C and -25 degrees C) had no significant influence on the treatment efficiency. A small fluctuation in effluent TOC concentration caused a dramatic change in effluent toxicity (Microtox). The effective concentration (EC20) (Microtox) was effective in detecting effluent toxicity.

Choice of grass or maize silages by lactating dairy cows: influence of supplementary protein, concentrate level and milk yield

Preference testing of two foods provides a means of assessing the relative value an animal places on the foods. Two experiments examined the relative choice of grass and maize silages by lactating dairy cows, and investigated whether protein supplementation, concentrate level or milk yield level of cow influenced this choice. In experiment 1, 16 cows including eight high (30 kg/day) and eight low (17 kg/day) yielding (milk level, ML) cows were offered a low (171 g/kg dry matter (DM)) or a high (300 g/kg DM) crude protein (CP) concentrate in eight 2×2 Latin squares. In experiment 2, four cows were offered a low (112 g/kg DM) or a high (334 g/kg DM) CP content of concentrate at a low (3·5 kg/day) or high (7 kg/day) concentrate level (CL) in a 4×4 Latin-square design.CP of concentrate did not influence the proportion of grass silage to maize silage eaten in either experiment. Also, neither ML of cows (experiment 1) nor CL (experiment 2) affected proportions of the two silages eaten. The mean proportions selected were 0·88:0·12 and 0·52:0·48 for grass and maize silages in experiments 1 and 2 respectively, which reflected differences between experiments in the digestibilities of the silages, and indicated that digestibility may be an important factor influencing the choice of silages.The CP, CL and ML treatments produced significant responses in silage and total DM intakes. Feeding behaviour studies showed the responses to CP were associated with differences in meal size, which is a function of duration of each meal and rate of intake. The number of meals taken per day was similar for all treatments and averaged 8·0 and 8·1 for experiments 1 and 2 respectively.It was concluded that whilst lactating cows modified their feeding behaviour in response to the diets available, there was no evidence they modified the proportions of the two silages selected in order to meet a target protein content in the total diet. It would appear therefore that other factors, of which digestibility may be important, have a higher priority in choice.

ASPECTOS BIOLÓGICOS E MORFOLÓGICOS DE MIGDOLUS FRYANUS (WESTWOOD, 1863) (COLEOPTERA: VESPERIDAE)

RESUMO Neste estudo machos e fêmeas de Migdolus fryanus foram coletados em campo, após o acasalamento e trazidos ao laboratório. Fêmeas foram individualizadas em baldes de plástico (20 L) contendo solo. Observou-se o número de ovos, o tamanho, a viabilidade, o período de incubação e o tamanho das larvas ao eclodirem. Dimensões de larvas recém-eclodidas e ovos foram obtidas com um micrômetro ocular de escala de 0,05 mm. Machos foram mantidos em cilindros de vidros (12 cm alt. X 12 cm Ø), fechados com placas de Petri (15 cm de Ø) e definida a longevidade. Utilizando-se 50 larvas estudou-se uma dieta artificial, na qual foi acrescida 50 g de cana-de-açúcar “in natura” moída. Para os estudos morfológicos, os adultos foram coletados em cana-de-açúcar, pastagens e café abandonado, e os caracteres foram observados com microscópio óptico. As medições para adultos e larvas maduras foram tomadas com paquímetro, de escala de 1 mm. Fêmeas depositaram 19 a 38 ovos/fêmea (X 29,4 ± 5,5), com viabilidade de 65 a 98 % (X 84,9 ± 11,6) e período de incubação de 17 a 25 dias (X 20,6 ± 0,9). Os ovos têm formato oval e mediram 3 a 5 mm (X 4,5 ± 3,7). A longevidade das fêmeas variou de 28 a 38 dias (X 32,5 ± 3,5) e de machos de 3 a 9 dias (X 5,8 ± 1,9). Larvas ao eclodirem mediram entre 4 a 6 mm. Na dieta as larvas foram mantidas por 2 anos, passando por 6 e 7 ecdises, mas não completaram o ciclo ovo-adulto. Os adultos apresentaram grandes variações morfológicas, tanto em dimensões quanto em coloração. Apenas a espécie M. fryanus foi constatada nos municípios estudados.

First Results of Detection of PRRSV and CSFV RNA by SYBR Green I-based Quantitative PCR

Porcine reproductive and respiratory syndrome (PRRS) and classical swine fever (CSF) cause significant economic losses to the swine industry worldwide. As both diseases cause similar symptoms, rapid and reliable detection of these diseases is essential for disease surveillance. A quantitative SYBR Green I-based reverse transcription-polymerase chain reaction (RT-PCR) is described for simultaneous and differential diagnosis. The established RT-PCR for the quantitation of PRRSV and CSFV cDNA was found to provide a broad dynamic range, detecting from 10(3) to 10(11) and 10(2) to 10(11) copies of cDNA per reaction, respectively. Sensitivity and specificity of this method were compared with those of conventional RT-PCR and both were equal or superior to the reference method. Reproducibility was tested and the assay was proved very reliable. The assay is timesaving, easy to handle, and highly sensitive and specific. Therefore, it is a powerful tool for detecting PRRSV and CSFV simultaneously for routine outbreak investigation.

MIGDOLUS FRYANUS (WESTWOOD, 1863) (COLEOPTERA: VESPERIDAE): PRAGA DA CULTURA DE CANA-DE-AÇÚCAR

RESUMO Migdolus fryanus (Westwood, 1863) (Coleoptera: Vesperidae) é um besouro que ataca as raízes e o rizoma da cana-de-açúcar, ocasionando sérios prejuízos aos canaviais, principalmente, no Estado de São Paulo. As larvas são difíceis de serem controladas em função do comportamento subterrâneo e da profundidade que podem atingir em determinadas épocas do ano. É um inseto de ciclo longo e que apresenta revoada dos adultos para o acasalamento, após as chuvas do mês de outubro. Atualmente, para o controle desse inseto, alguns produtores de cana realizam um monitoramento por meio de armadilhas contendo feromônio sexual para localizar as áreas infestadas e, posteriormente, aplicar inseticidas no sulco, na época do plantio (cana planta), ou nos lados da linha após a colheita da cana (cana soca). Esta revisão enfoca estudos sobre os aspectos biológicos e comportamentais de M. fryanus.

ESTUDOS ECOLÓGICOS E COMPORTAMENTAIS DE MIGDOLUS FRYANUS (WESTWOOD, 1863) (COLEOPTERA: VESPERIDAE), EM CULTURA DE CANA-DE-AÇÚCAR, EM QUATRO MUNICÍPIOS DO ESTADO DE SÃO PAULO

RESUMO Infestações por Migdolus fryanus (Westwood, 1863) (Col: Vesperidae) podem resultar em severos prejuízos à cultura da cana-de-açúcar. Na presente pesquisa estudou-se o comportamento de revoada em canaviais de 4 municípios de São Paulo (Olímpia, Catanduva, Promissão e Teodoro Sampaio), entre os meses de outubro de 2001 e março de 2003, realizando-se 3 observações por município em cada ano. Em Catanduva, SP foi estudada a flutuação de larvas por intermédio de abertura de trincheiras no período compreendido entre março de 2002 e fevereiro de 2004. Além disso, no mês de setembro de 2003 foi comparado entre três municípios (Olímpia, Catanduva e Teodoro Sampaio) o índice de infestação de larvas por touceira de cana, em reboleira atacada. As revoadas ocorreram sempre após chuvas, algumas duraram até 7 dias e aconteceram entre os meses de outubro e março. Fêmeas apareceram de forma bem sincronizada entre 8h e 10h da manhã e permaneceram no solo até a chegada do macho. Já os machos foram freqüentes o dia todo, aparecendo primeiro que as fêmeas. A cópula durou entre 5 a 30 segundos. As larvas foram mais freqüentes entre março a setembro e em maior número no período de baixa pluviosidade (julho a setembro). O maior índice por touceira ocorreu em Teodoro Sampaio, média de 3,96/larvas por touceira, e Olímpia, média de 3,88/larvas por touceira que diferiram significativamente de Catanduva, média de 1,6/larva por touceira. Com relação às reboleiras estudadas ocorreu diferença significativa do número de larvas por touceiras apenas em Olímpia, SP.

Inactivation of infectious bursal disease virus by binary ethylenimine and formalin

In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. Viral suspensions were subjected to inactivation with BEI and formalin for pre-set time intervals. BEI was employed at concentrations of 0.001 and 0.002 mol/L while formalin was used at 0.1% and 0.2%. Sampling was done at 6, 12, 24, 36 and 48 h of incubation and samples were tested for their inactivation status in 9-day-old embryonated eggs and 3-week-old broiler chickens. IBDV was completely inactivated by 0.001 and 0.002 mol/L BEI after 36 h of incubation at 37 degrees C, whereas formalin at 0.1% and 0.2% concentrations inactivated IBDV in 24 h.

Comparative study of Anaplasma parasites in tick carrying buffaloes and cattle

A comparative study on the prevalence of Anaplasma parasite was conducted on ticks carrying buffaloes and cattle. Five hundred blood samples of both animals (250 of each) were collected during February, March and April. Thin blood smears on glass slides were made, fixed in 100% methyl alcohol and examined. Microscopic examination revealed that 205 (41%) animals had Anaplasma parasites, out of which 89, 44 and 72 animals had Anaplasma marginale, Anaplasma centrale and mixed infection respectively. Infected buffaloes and cattle were 75 and 130 respectively. The infection in female was 53 and 92 in buffaloes and cattle respectively. Twenty-two and 92 blood samples of male were found positive in buffaloes and cattle respectively. Comparative study revealed that the cattle were 26.82% more susceptible than buffaloes. The parasite prevailing percentage in female of both animals was slightly higher than that of the male. This investigation was aimed at studying the comparative prevalence of Anaplasma parasite in tick carrying buffaloes and cattle.

Seroprevalence of hepatitis C virus specific antibodies among Iraqi children with thalassaemia

The seroprevalence of hepatitis C virus (HCV) specific antibodies and HCV genotypes distribution were studied among 559 Iraqi children with thalassaemia in receipt of repeated blood transfusions. HCV-specific antibodies were detected in 376 (67.3%) serum samples using third-generation enzyme immunoassay and confirmatory immunoblot assays. Of 78 randomly selected sera, 48 (61.5%) were HCV-RNA positive. HCV genotypes 1a, 1b, 4 and mixed 1b and 4 were demonstrated in 13 (27.1%), 11 (22.9%), 17 (35.4%) and 7 (14.6%) sera respectively. Strict measures for the controlling the spread of HCV are needed by introducing advanced techniques for blood donor screening.

Central scotoma associated with intraocular silicone oil tamponade develops before oil removal

BACKGROUND

Unexplained sudden visual loss after removal of silicone oil from the eye has recently been described. We report the occurrence and features of unexplained central scotoma developing with silicone oil in situ in the vitreous cavity.

METHODS

A retrospective case series of five patients (from two centres) who reported a central scotoma commencing during silicone oil tamponade was studied. All patients had vitrectomy for macula-on retinal detachment, with ultra-purified silicone oil tamponade (four out of five had giant retinal tear). Investigations included visual acuity, intraocular pressure, optical coherence tomography, fluorescein angiography, visual fields and electrophysiology.

RESULTS

All patients reported a central scotoma that appeared during oil tamponade. Visual acuity fell by a mean of 0.93 LogMAR units after onset of the scotoma. After cataract extraction and oil removal, vision remained reduced by a mean of 0.8 units. The mean duration of oil in the eye was 2.7 months when the scotoma was noted by the patient. Investigations were performed after removal of oil. Fluorescein angiography (FFA) was performed in two cases and optical coherence tomography (OCT) in five patients. No abnormality was demonstrated. Electrophysiology was performed in five patients with pattern electroretinography suggestive of macular dysfunction in four patients.

CONCLUSION

This is the first case series describing central scotoma associated with silicone oil in situ. Electrophysiology indicated macular dysfunction in most cases. We suggest that early removal of oil in cases with good visual potential should be considered to avoid this sight-threatening complication.

PATOGENICIDADE DE NEMATÓIDES ENTOMOPATOGÊNICOS A OVOS E LARVAS DE MIGDOLUS FRYANUS (WESTWOOD, 1863) (COLEOPTERA: VESPERIDAE)

RESUMO Nematóides entomopatogênicos, nativos, Steinernema glaseri (Steiner, 1929) e Heterorhabditis indica Poinar, Karunakar & David, 1992 (IBCB-n5) foram avaliados quanto ao potencial parasítico, contra ovos e larvas de Migdolus fryanus, em laboratório. Ovos do vesperídeo foram expostos a Juvenis Infectivos (JI) de H. indica (60 e 600 JI/ovo). Em cada tratamento usou-se 3 repetições, com 5 ovos. Não ocorreu diferença significativa entre os tratamentos. Porém, constatou-se a penetração do nematóide e redução da viabilidade dos ovos infectados. Avaliou-se também, S. glaseri e H. indica (600 JI/larva) contra larvas recém eclodidas de M. fryanus. Os tratamentos tiveram 4 repetições, cada uma com 5 larvas. S. glaseri causou 100% de mortalidade e H. indica H. Indica 80%, diferindo significativamente da testemunha. Finalmente, observou-se o efeito de S. glaseri e H. indica em 2 dosagens (400 e 800 JI/Inseto) contra larvas em final de desenvolvimento. Foram considerados 5 tratamentos com 7 repetições, cada uma com 3 larvas. Neste caso, não ocorreu diferença significativa entre as dosagens dos nematóides, porém, H. indica nas suas 2 dosagens, mostrou-se mais patogênico que a testemunha e do S. glaseri, proporcionando uma mortalidade larval de 76,43 e 71,57%, respectivamente. Os resultados demonstraram que esses nematóides têm potencial para serem pesquisados como agente de controle biológico de M. fryanus em cultivos de cana-de-açúcar, no Estado de São Paulo, Brasil.

Auditory Evoked Potential Patterns to Voiced and Voiceless Speech Sounds in Adult Developmental Dyslexics with Persistent Deficits

Auditory evoked potentials (AEPs) were recorded from eight developmental dyslexic adults with persistent reading, spelling and phonological deficits, and 10 non-dyslexic controls to voiced (/ba/) and voiceless (/pa/) consonant-vowel syllables. Consistent with previous data, non-dyslexics coded these stimuli differentially according to the temporal cues that form the basis of the voiced/voiceless contrast: AEPs had time-locked components with latencies that were determined by the temporal structure of the stimuli. Dyslexics were characterized by one of two electrophysiological patterns: AEP pattern I dyslexics demonstrated a differential coding of stimuli on the basis of some temporal cues, but with an atypically large number of components and a considerable delay in AEP termination time; AEP pattern II dyslexics demonstrated no clear differential coding of stimuli on the basis of temporal cues. These data reveal the presence of anomalies in cortical auditory processing which could underlie persistent perceptual and linguistic impairments in some developmental dyslexics. Furthermore, scalp AEP distribution maps showing the difference observed between /ba/ and /pa/ activity over time suggest that the regions implicated in the processing of crucial time-related acoustic cues were not systematically lateralized to the left hemisphere like they were for non-dyslexics. These findings may be conducive to a better understanding and treatment of perceptual dysfunctions in developmental language disorders.

The relation of volume with outcome in phacoemulsification surgery

BACKGROUND/AIMS

High case volume has been associated with better health outcomes for a variety of procedures and conditions including coronary angioplasty, carotid endarterectomy, colorectal surgery, and various types of cancer surgery. The association of volume and outcome has important implications for patient safety and healthcare delivery planning. The relation between surgical volume and outcome has not, as far as is known, been looked at for phacoemulsification alone.

METHODS

All cataract surgery performed from 1996 to 2001 by six consultant surgeons was reviewed. Using theatre logbooks and cross checking with the hospital database, the total number of phacoemulsification procedures performed per surgeon per year was calculated. The total number of operations in which it was judged that significant intraoperative complications occurred was also counted.

RESULTS

When the data were pooled for all the surgeons there was evidence that complication rate decreased over time (Spearman's rho = -0.319, p = 0.058). If the data were pooled from all the years and all the surgeons then there was strong evidence of a decrease in complication rate with an increase in the number of cases (Spearman's rho = -0.63, p<0.01).

CONCLUSIONS

This study is the first to describe a possible relation between volume of surgery and the outcome (as measured by complication rates) for phacoemulsification. There are however some caveats in that the issue of case mix was not addressed and that the results are from a single unit and may not necessarily be generalisable

Dyslexia: the articulatory hypothesis revisited

Articulatory disorders have been associated with developmental phonological dyslexia in the literature. However, very few information is available about the articulatory movements involved in speech production in dyslexic children. This study uses aerodynamic/acoustic data to explore how dyslexic children produce bilabial stops in French (/b, p/) within a sentence where they occurred in two positions and in three vowel environments. Average durations of articulatory closure and release were calculated in 10 phonological dyslexic children and two groups of age-matched and reading age-matched controls. Moreover, deviation from a standard pronunciation of the same material was evaluated separately by blind examiners. Our results reveal differences in the timing of the articulatory movements between dyslexics and normal controls, as well as more deviations from the target consonant for the dyslexics than for the controls. These observations are consistent with recent findings pointing to a general deficit in fine motor control in dyslexia.

Increased fecal IgE among infants in a rural community of Egypt: an analysis of associated risk factors

Newborns in rural Bilbeis, Egypt were followed to 1-year of age to document the incidence and risk factors associated with the development of fecal IgE. Factors associated with increased fecal IgE included infants aged 3-6 months (relative risk (RR) = 3.28, 95 per cent confidence intervals (CI) = 1.03-13.60, p < 0.05) and mother being vaccinated antenatally (RR = 2.17, CI - 1.01-4.61, p < 0.05). Decreased fecal IgE was observed with consumption of rice (RR = 0.37, CI = 0.12-0.94, p < 0.05), biscuits (RR = 0.43, CI = 0.15-0.99, p < 0.05), potatoes (RR = 0.39, CI = 0.11-0.98, p < 0.05), and fruits and vegetables (RR = 0.20, CI = 0.02-0.80, p < 0.05). After multivariate adjustment, increased risk was observed with consumption of milk pudding (RR = 7.48, CI = 1.54-36.20, p < 0.05) and wet-nursed infants (RR = 2.77, CI = 1.17-6.54, p < 0.05). Infants who were completely breastfed (RR = 0.13, CI = 0.02-0.68, p < 0.05) and infants' family owning a television set (RR = 0.29, CI = 0.12-0.67, p < 0.05) were less likely to develop fecal IgE. Our findings indicate that prelacteal feeding with certain foods, early supplementation of breastfeeding, and sociodemographic factors are associated with increased fecal IgE.

Sociodemographic, environmental and clinical risk factors for developing persistent diarrhoea among infants in a rural community of Egypt

The study documents the incidence of persistent diarrhoea and its sociodemographic, household, environmental and clinical risk factors. One hundred and fifty-two newborns were followed for the first 12 months of life in Bilbeis, Egypt. The household of each participant was surveyed at baseline and was visited twice a week. The study infants experienced persistent diarrhoea at a rate of 0.51 episode/case per year. Development of persistent diarrhoea was associated with water storage in mud-containers (Odds ratio [OR] = 4.36, confidence interval [CI] 1.4-14.8), pump-water supply (OR = 3.5, CI 1.2-10.2), and absence of a latrine in the household (OR = 2.74, CI 1.01-7.38). Detection of faecal IgE (OR = 3.32, CI 1.0-10.9) and high stool frequency (OR = 2.95, CI 1.1-7.8) appeared as important clinical predictors for the onset of persistent diarrhoea. The incidence of persistent diarrhoea among young infants in Bilbeis, Egypt, was high. Sociodemographic, environmental and clinical parameters were important risk factors for the development of persistent diarrhoea.

Impact of breast-feeding on Giardia lamblia infections in Bilbeis, Egypt

A total of 152 infants were followed from birth to 1 year of age in a rural community of Egypt to document Giardia lamblia infection and to determine the effect of breast-feeding on enteric infections by this protozoan. Asymptomatic Giardia infections persisted as long as 4 months, with a mean duration of excretion of 7.18 weeks. The incidence of asymptomatic infection was 4.5 episodes per child-year. Exclusively breast-fed infants had lower risk for asymptomatic (odds ratio [OR] = 0.66, 95% confidence interval [CI] = 0.45-0.96, P < 0.05) and symptomatic infections (relative risk [RR] = 0.50, 95% CI = 0.27-0.90, P < 0.05). Furthermore, breast-fed infants had fewer clinical manifestations, including mucus in stool (23.8% versus 76.2%, P = 0.08), loss of appetite (17.6% versus 82.3%, P < 0.05), and abdominal tenderness (17% versus 82.9%, P < 0.05) compared with infants who were not exclusively breast-fed. Breast-feeding should be considered as an effective means to prevent Giardia infections and should be encouraged in regions where G. lambia is highly endemic.

[Developmental dyslexia: contribution of modern neuropsychology]

In France about 1 million children are thought to present learning disabilities for reading that in most cases correspond to developmental dyslexias. These are specific and constitutional deficits that prevent rapid and automatic reading abilities from developing, in spite of a normal intelligence and normal visual and auditory acuity. The most frequent form of dyslexia is called "phonological dyslexia" as it results from a deficit of perception and manipulation of phonemes (i.e. "phonological awareness"). Functional neuro-imaging has great potential for helping understand such functional deficits that are likely to be caused by microscopic abnormalities such as micro-polygyria localised in the perisylvian cortex. Tomographic methods have shown deficits of activation of these cortical areas. Electrophysiological methods revealed abnormalities of various events such as MMN or N400, and more recently, delayed latencies of earlier markers suggesting deficits of encoding short-lived features of speech signal.