A comprehensive factorial design study of variables affecting CaCO3 scaling under magnetic water treatment.

Magnetic water treatment (MWT) could be an interesting alternative to chemical treatment to prevent scaling and has been used as an antiscaling treatment for domestic and industrial equipment. A two level-three factor (2(3)) full factorial design was used to evaluate the effects of pH (6-7.5), flow rate (0.54-0.94) and application of a magnetic field on the induction time (IT), total precipitation (TP) rate and homogeneous precipitation (HP) rate of calcium carbonate (CaCO3) scale from hard water. The experimental results and statistical analysis show that the pH, flow rate and interaction between pH and magnetic field have negative effects on IT response. In the case of TP rate response, the magnitude of the main influence is attributed to the magnetic field, followed by pH value and their interaction. Flow rate and pH value have a negative effect on HP rate response, but their interaction has a positive effect. Within these factor ranges, these studied responses predicted by the models were in good agreement with the experimental values. The coefficient of determination (R(2)) for reduction time, TP ratio and HP ratio were 97.8%, 99.12% and 99.92%, respectively. These results were analyzed statistically using Minitab 15.

Simulation of hydrogen sulphide absorption in alkaline solution using a packed column.

In this work, a simulation tool was developed for hydrogen sulphide (H2S) removal in an alkaline solution in packed columns working at countercurrent. Modelling takes into account the mass-transfer enhancement due to the reversible reactions between H2S and the alkaline species (CO(²â»)(3), HCO⁻(3), and HO⁻) in the liquid film. Many parameters can be controlled by the user such as the gas and liquid inlet H2S concentrations, the gas and liquid flow rates, the scrubbing liquid pH, the desired H2S removal efficiency, the temperature, the alkalinity, etc. Since the influence of the hydrodynamic and mass-transfer performances in a packed column is well known, the numerical resolutions performed were dedicated to the study of the influence of the chemical conditions (through the pH and the alkalinity), the temperature and the liquid-to-gas mass flow rate ratio (L/G). A packed column of 3 m equipped with a given random packing material working at countercurrent and steady state has been modelled. The results show that the H2S removal efficiency increases with the L/G, the pH, the alkalinity and more surprisingly with the temperature. Alkalinity has a very significant effect on the removal efficiency through the mass-transfer enhancement and buffering effect, which limits pH decreasing due to H2S absorption. This numerical resolution provides a tool for designers and researchers involved in H2S treatment to understand deeper the process and optimize their processes.

Necrotizing otitis externa: 19 cases' report.

Necrotizing otitis externa is an uncommon but severe infectious disease of the external auditory canal. Patients at risk are those immunodepressed or having diabetes. The causal germ is often Pseudomonas aeruginosa. Over a period of 10 years (1997-2006), we treated 19 patients: 94.7% had diabetes (insulin dependent in 6 cases). The causal germ was P. aeruginosa in 59% of cases. The pretherapeutic work-up included a computed tomography and a scintigraphy practiced in order to confirm diagnosis and assess the extension. Medical treatment was based on a parenteral antibiotic therapy using a third-generation cephalosporin and a fluoroquinolones. Local treatment of the auditory canal including cleaning and application of antimicrobial agents was performed in all the cases. Surgical debridement of soft tissue and infected bone was performed in one patient who did not respond to medical management. Repeated scintigraphies with gallium were used to follow the course under treatment in only three cases. We had a 89.4% cure rate with only three cases of recurrence. We reviewed the data in the literature on necrotizing otitis externa and present the important diagnostic, imaging, and therapeutic aspects of the disease.

[Recurrent upper respiratory tract infections in children and allergy. A cross-sectional study of 100 cases]. / Infections recidivantes des voies aeriennes superieures de l'enfant et allergie. Etude transversale à propos de 100 cas.

BACKGROUND: Upper respiratory tract (URT) infections are common in children. The knowledge of their risk factors allows in some cases better management. The aim of our study is to evaluate the role of allergy in this pathology. METHODS: Through a cross-sectional study about 100 children having recurrent URT infections, we evaluated the prevalence of allergy in order to find a relation between the two pathologies in general, and between allergy and each recurrent pathology. The results were compared with those of a reference group involving 164 children. RESULTS: Our study confirms a statistically significant association between allergy and recurrent URT infections (p=0.01), also between allergy and rhinopharyngitis (p=0.02), rhinosinusitis (p=0.001) and acute otitis media (p=0.01). CONCLUSION: Allergy represents a risk factor for recurrent URT infections, particularly for rhinopharyngitis, rhinosinusitis and acute otitis media. Adequate management of allergy may consequently be beneficial for the treatment and the prevention of these infections.

Intraparotid ductal ectasia: rare cause of parotid swelling.

A 41-year-old patient was hospitalised for a chronic right parotid mass. A cervical ultrasound revealed a cystic mass of the parotid. Cervical MRI found a ductal ectasia of the parotid and submandibular glands associated with a retention cyst of the right parotid. He had a right total parotidectomy. Histopathological examination of the lesion revealed a multilocular cystic mass with a diffuse glandular ectasia of salivary ducts. The patient had an uneventful postoperative course without any recurrence of symptoms.

Oleosin gene family of Coffea canephora: quantitative expression analysis of five oleosin genes in developing and germinating coffee grain.

Coffee grains have an oil content between 10% and 16%, with these values associated with Coffea canephora (robusta) and C. arabica (arabica), respectively. As the majority of the oil stored in oil seeds is contained in specific structures called oil bodies, we were interested in determining whether there are any differences in the expression of the main oil body proteins, the oleosins, between the robusta and arabica varieties. Here, we present the isolation, characterization and quantitative expression analysis of six cDNAs representing five genes of the coffee oleosin family (CcOLE-1 to CcOLE-5) and one gene of the steroleosin family (CcSTO-1). Each coffee oleosin cDNA encodes for the signature structure for oleosins, a long hydrophobic central sequence containing a proline KNOT motif. Sequence analysis also indicates that the C-terminal domain of CcOLE-1, CcOLE-3 and CcOLE-5 contain an 18-residue sequence typical of H-form oleosins. Quantitative RT-PCR showed that the transcripts of all five oleosins were predominantly expressed during grain maturation in robusta and arabica grain, with CcOLE-1 and CcOLE-2 being more highly expressed. While the relative expression levels of the five oleosins were similar for robusta and arabica, significant differences in the absolute levels of expression were found between the two species. Quantitative analysis of oleosin transcripts in germinating arabica grain generally showed that the levels of these transcripts were lower in the grain after drying, and then further decreased during germination, except for a small spike of expression for CcOLE-2 early in germination. In contrast, the levels of CcSTO-1 transcripts remained relatively constant during germination, in agreement with suggestions that this protein is actively involved in the process of oil body turnover. Finally, we discuss the implications of the coffee oleosin expression data presented relative to the predicted roles for the different coffee oleosins during development and germination.

[Langerhans cell histiocytois of the thyroid: a rare disease not to be ignored]. / L'histiocytose langerhansienne de la thyroïde: une localisation rare à ne pas méconnaître.

Thyroid involvement by Langerhans cell histiocytosis is rare. We report the case of a ten-year old boy who presented with a 5 cm goitre. He was treated for diabetes insipidus 14 months before. Thyroid isotopic scan showed hypoactivity of right lobe and revealed a cold left nodule. The patient was treated by right lobo-isthmectomy with adjuvant corticotherapy and chemotherapy (vinblastine). He is well with 12 months follow-up. Microscopic analysis demonstrated a diffuse infiltrate of thyroid parenchyma by sheets of CD1a positive Langerhans cells associated with lymphocyte foci. This case is remarkable by the abundance of Langerhans cells and scarcity of eosinophils. The diagnosis of thyroid langerhans cell histiocytosis should not be ignored in both children and adult patients.

[Facial nerve paralysis secondary to acute otitis media]. / Paralysie faciale périphérique suite à une otite moyenne aiguë

OBJECTS: To discuss clinical presentation and therapeutic approaches of facial paralysis in acute otitis media. METHODS: We present five cases of facial palsy in children with acute otitis media managed in our ENT department during a period of 12 years (2001-2012). RESULTS: The mean age was 14.2 years; sex ratio was 0.66. All patients presented with a facial asymmetry, but only 3 of them had otalgia before the onset of facial asymmetry. The facial palsy delay was 3.3 days. The ear examination showed that the tympanic membrane was congestive in 4 patients, associated with a bulging in 2 patients, and a small perforation in one patient. Our patients presented grade III to IV initial facial palsy according to House and Brackmann staging. Computed tomography scan revealed a dehiscence of the bony facial canal in one patient. Antibiotic therapy associated with intravenous corticosteroids was administered in all patients. All patients underwent a facial kinesis therapy. A progressive improvement of facial palsy was observed in 4 patients and complete recovery of facial function in one case. DISCUSSION: Conservative treatment associating intravenous antibiotic and corticosteroids with or without myringotomy is the standard approach.

[Sinonasal inverted papilloma: 43 cases]. / Le papillome inversé nasosinusien : 43 cas.

PURPOSE: Inverted papilloma (IP) is a common epithelial tumor arising from the nasal vault. The aim of our study was to evaluate the advantages, the results and the limits in the treatment of this tumor. PATIENTS AND METHOD: Retrospective study of 43 patients over the period 1989-2009. RESULTS: The mean age was 53.3 years. We found a maxillary sinus extension in 40 cases and ethmoidal extension in 27 cases. Twenty-nine patients were treated through an endoscopic endonasal approach. A vestibular approach was used in three patients. A paralateral nasal approach was used for 12 cases. We observed a recurrence in 9.3% of the all cases. CONCLUSION: The treatment of IP is surgical. Their high potential of local aggressiveness, fear of recurrence and the possibility of the occurrence of a malignancy require radical treatment.

Phosphate recovery through struvite precipitation by CO2 removal: effect of magnesium, phosphate and ammonium concentrations.

In the present study, the precipitation of struvite (MgNH(4)PO(4)·6H(2)O) using the CO(2) degasification technique is investigated. The precipitation of struvite was done from supersaturated solutions in which precipitation was induced by the increase of the solution supersaturation concomitant with the removal of dissolved carbon dioxide. The effect of magnesium, phosphate and ammonium concentrations on the kinetics and the efficiency of struvite precipitation was measured monitoring the respective concentrations in solution. In all cases struvite precipitated exclusively and the solid was characterized by powder XRD and FTIR. The morphology of the precipitated crystals was examined by scanning electronic microscopy and it was found that it exhibited the typical prismatic pattern of the struvite crystals with sizes in the range between 100 and 300 µm. The increase of magnesium concentration in the supersaturated solutions, resulted for all phosphate concentration tested, in significantly higher phosphate removal efficiency. Moreover, it is interesting to note that in this case the adhesion of the suspended struvite crystals to the reactor walls was reduced suggesting changes in the particle characteristics. The increase of phosphate concentration in the supersaturated solutions, for the magnesium concentrations tested resulted to the reduction of struvite suppression which reached complete suppression of the precipitate formation. Excess of ammonium in solution was found favour struvite precipitation. Contrary to the results found with increasing the magnesium concentration in solution, higher ammonium concentrations resulted to higher adhesion of the precipitated crystallites to the reactor walls. The results of the present work showed that it is possible to recover phosphorus in the form of struvite from wastewater reducing water pollution and at the same time saving valuable resources.

Isolation and characterization of cDNA encoding three dehydrins expressed during Coffea canephora (Robusta) grain development.

BACKGROUND AND AIMS: Dehydrins, or group 2 late embryogenic abundant proteins (LEA), are hydrophilic Gly-rich proteins that are induced in vegetative tissues in response to dehydration, elevated salt, and low temperature, in addition to being expressed during the late stages of seed maturation. With the aim of characterizing and studying genes involved in osmotic stress tolerance in coffee, several full-length cDNA-encoding dehydrins (CcDH1, CcDH2 and CcDH3) and an LEA protein (CcLEA1) from Coffea canephora (robusta) were isolated and characterized. METHODS: The protein sequences deduced from the full-length cDNA were analysed to classify each dehydrin/LEA gene product and RT-PCR was used to determine the expression pattern of all four genes during pericarp and grain development, and in several other tissues of C. arabica and C. canephora. Primer-assisted genome walking was used to isolate the promoter region of the grain specific dehydrin gene (CcDH2). KEY RESULTS: The CcDH1 and CcDH2 genes encode Y(3)SK(2) dehydrins and the CcDH3 gene encodes an SK(3) dehydrin. CcDH1 and CcDH2 are expressed during the final stages of arabica and robusta grain development, but only the CcDH1 transcripts are clearly detected in other tissues such as pericarp, leaves and flowers. CcDH3 transcripts are also found in developing arabica and robusta grain, in addition to being detected in pericarp, stem, leaves and flowers. CcLEA1 transcripts were only detected during a brief period of grain development. Finally, over 1 kb of genomic sequence potentially encoding the entire grain-specific promoter region of the CcDH2 gene was isolated and characterized. CONCLUSIONS: cDNA sequences for three dehydrins and one LEA protein have been obtained and the expression of the associated genes has been determined in various tissues of arabica and robusta coffees. Because induction of dehydrin gene expression is associated with osmotic stress in other plants, the dehydrin sequences presented here will facilitate future studies on the induction and control of the osmotic stress response in coffee. The unique expression pattern observed for CcLEA1, and the expression of a related gene in other plants, suggests that this gene may play an important role in the development of grain endosperm tissue. Genomic DNA containing the grain-specific CcDH2 promoter region has been cloned. Sequence analysis indicates that this promoter contains several putative regulatory sites implicated in the control of both seed- and osmotic stress-specific gene expression. Thus, the CcDH2 promoter is likely to be a useful tool for basic studies on the control of gene expression during both grain maturation and osmotic stress in coffee.

Mutational analysis of the mitochondrial 12S rRNA and tRNASer(UCN) genes in Tunisian patients with nonsyndromic hearing loss.

We explored the mitochondrial 12S rRNA and the tRNASer(UCN) genes in 100 Tunisian families affected with NSHL and in 100 control individuals. We identified the mitochondrial A1555G mutation in one out of these 100 families and not in the 100 control individuals. Members of this family harbouring the A1555G mutation showed phenotypic heterogeneity which could be explained by an eventual nuclear-mitochondrial interaction. So, we have screened three nuclear genes: GJB2, GJB3, and GJB6 but we have not found correlation between the phenotypic heterogeneity and variants detected in these genes. We explored also the entire mitochondrial 12S rRNA and the tRNASer(UCN) genes. We detected five novel polymorphisms: T742C, T794A, A813G, C868T, and C954T, and 12 known polymorphisms in the mitochondrial 12S rRNA gene. None of the 100 families or the 100 controls were found to carry mutations in the tRNASer(UCN) gene. We report here the first mutational screening of the mitochondrial 12S rRNA and the tRNASer(UCN) genes in the Tunisian population which describes the second family harbouring the A1555G mutation in Africa and reveals novel polymorphisms in the mitochondrial 12S rRNA gene.

A novel autosomal recessive non-syndromic deafness locus, DFNB66, maps to chromosome 6p21.2-22.3 in a large Tunisian consanguineous family.

Hereditary non-syndromic deafness is extremely heterogeneous. Autosomal recessive forms account for approximately 80% of genetic cases. Autosomal recessive non-syndromic sensorineural deafness segregating in a large consanguineous Tunisian family was mapped to chromosome 6p21.2-22.3. A maximum lod score of 5.36 at theta=0 was obtained for the polymorphic microsatellite marker IR2/IR4. Haplotype analysis defined a 16.5-Mb critical region between microsatellite markers D6S1602 and D6S1665. The screening of 3 candidate genes, COL11A2, BAK1 and TMHS, did not reveal any disease causing mutation, suggesting that this is a novel deafness locus, which has been named DFNB66. A search in the Human Cochlear EST Library for ESTs located in this critical interval allowed us to identify several candidates. Further investigations on these candidates are needed in order to identify the deafness-causing gene in this Tunisian family.