Interaction of hydrated metals with chemically modified hexagonal boron nitride quantum dots: wastewater treatment and water splitting.

The electronic and adsorption properties of chemically modified square hexagonal boron nitride quantum dots are investigated using density functional theory calculations. The free energy and frequency calculations show that all the boron nitride flakes are stable before/after modification and metal adsorption. Edge modification significantly enhances the stability and interactivity of the flake. For instance, the free energy of binding decreases from -6.5 eV in the hydrogenated flake to -7.1 eV in the pristine one and the dipole moment increases from 4.5 D to 53.7 D, respectively. A wide spectrum of band gaps can also be achieved, where the band gap can be smoothly varied from ∼6 eV in edge fluorinated flakes to 0.2 in sulfurated ones. Six hydrated metals, Cd, Co, Cr, Cu, Fe, and Zn, are considered for adsorption by the flakes. The transition metals are highly selected by the flakes while heavy metals are weakly adsorbed. All hydrated metals are physically adsorbed by the edge and surface of hydrogenated flakes except Cu, which is chemically adsorbed. Chemical groups or elements attached to the flake strongly enhance the adsorption strength; the adsorption energy of hydrated Cr on the surface increases from 0.6 eV to 8.6 eV after attaching two COOH groups to the surface. Hydrogen evolution has also been observed through the adsorption process. The calculated low overpotential for the oxygen evolution reaction (0.52 V) and hydrogen adsorption strength (0.11 eV) for the hydrogen evolution reaction indicate that boron nitride quantum dots are not only potential candidates for the removal of different metals from wastewater but also for efficient water splitting.

Vaccine preventable diseases and immunization during humanitarian emergencies: challenges and lessons learned from the Eastern Mediterranean Region (Editorial).

The last few years have seen the WHO Eastern Mediterranean Region suffer from multiple wars and conflicts leading to humanitarian emergencies of unprecedented magnitude. In addition to the many lives lost and affected, the conflicts have significantly impacted the infrastructure needed for delivery of healthcare services. Approximately 30 million people have fled their countries; the refugee population in Jordan has doubled and even tripled in Lebanon. The population displacement and resettlement, overcrowding, poverty, poor sanitation, and malnutrition due to food shortages have increased morbidity and mortality from various diseases, notably communicable diseases.

[Epidemiology of rotavirus gastroenteritis among children under 5 years of age in Tunisia - results of sentinel hospital surveillance 2009 to 2011]. / Épidémiologie des gastroentérites à rotavirus chez les enfants âgés de moins de cinq ans en Tunisie - Résultats de la surveillance sentinelle hospitalière 2009 à 2011.

BACKGROUND: Rotavirus is the major cause of severe acute gastroenteritis among young children. The objectives of this study were to assess the epidemiology, clinical and virological features of community-acquired rotavirus acute gastroenteritis, in children under 5 years of age, hospitalized in Tunisia. METHODS: A multicenter prospective observational study was conducted from April 2009 to March 2011, in 11 sentinel pediatric departments. Clinical data and stool samples were collected for all children under 5 years, admitted for acute gastroenteritis. Rotavirus was detected by Elisa immunoassay test and genotyped for G and P by semi-nested multiplex RT-PCR. RESULT: A total of 621 children were enrolled in this study. Rotavirus was detected in 30.3% of cases (95% CI [26.7-33.9]). The estimated incidence rate of rotavirus acute gastroenteritis was 11 cases/100,000 child-years (95% CI [9.43-12.57]). This infection affected predominantly children aged under 24 months, and occurred mainly in winter (55.3%). Vomiting, fever and dehydration were observed in 79.6%, 69.5% and 57% respectively. Genotype analysis identified four G types (G1, G2, G3 and G4) and 4 P types (P[4], P[6], P[8] and P[9]). The most common G/P combination was G3P[8] (24.4%), followed by G4P[8] (13.3%) and G1P[8] (6.5%). CONCLUSION: These results highlight the frequency and potential severity of rotavirus acute gastroenteritis in pediatric hospital settings. The present study could provide a sufficient database to make a decision related to the introduction of rotavirus vaccine in Tunisian national immunization program.

Relationship between electropherotypes and VP7/VP4 genotypes of group A rotaviruses detected between 2000 and 2007 in Tunisian children.

BACKGROUND: Rotaviruses are the most frequent agents associated with diarrhoea in children worldwide. Analysis of mobility of the 11 segments of genomic RNA by polyacrylamide gel electrophoresis (PAGE) yields a pattern which is characteristic for a particular rotavirus isolate. The group A rotaviruses can be further characterized by analysis of VP7 and VP4 genes specificities, responsible for rotavirus classification into G and P genotypes, respectively. The aim of the present study was to detect a relationship between electropherotype pattern and molecular characteristics of the rotavirus strains. MATERIAL AND METHODS: Were analyzed 278 rotavirus-positive specimens by PAGE and G/P-genotyped by multiplex semi-nested RT-PCR. Pearson's correlation tests were used for statistical analysis. RESULTS: Twelve different electropherotypes were visualized, eight with a long profile (186 cases) and four with a short one (87 cases). Concerning VP7 types, G2 viral strains were found to be predominant and were detected in 91 specimens (32.7%). Strains with G1, G3, G4, G8 and G9 specificities were detected in 62 (22.3%), 82 (29.5%), 13 (4.7%), two (0.7%) and seven cases (2.5%), respectively. The results of VP4 genotyping showed a predominance of P[8] genotype which comprised half of the strains identified (139 cases, 50%). VP4 P[4], P[6] and P[11] were found in 83 (29.9%), 31 (11.1%) and 11 (4.0%) specimens, respectively. A high rate of mixed strains was also found (1.8% mixed electropherotypes, 7.6% G-mixed and 5% P-mixed strains). Electropherotype pattern of rotavirus strains was significantly correlated with VP7 genotype (p=0.018) and with VP4 genotype specificities (p<0.001).

[Evolution of group A Rotavirus strains circulating in Tunisia over a 3-year period (2005-2007)]. / Évolution des souches de Rotavirus du groupe A en circulation en Tunisie sur une période de trois ans (2005-2007).

BACKGROUND: Rotaviruses are the most frequent agents associated with diarrhoea in children worldwide. Analysis of mobility of the 11 segments of genomic RNA by polyacrylamide gel electrophoresis (PAGE) yields a pattern which is characteristic for a particular rotavirus isolate. The group A rotaviruses can be further characterized by analysis of VP7 and VP4 genes specificities, responsible for rotavirus classification into G and P genotypes, respectively. The aim of the present study was to determine the evolution of group A Rotavirus strains circulating in Tunisia over a 3-year period (2005-2007). MATERIAL AND METHODS: A total of 1503 stool samples collected from children less than five years old, consulting or hospitalised in Tunisia for diarrhoea between 2005 and 2007, were screened for the presence of group A Rotaviruses. Rotavirus-positive specimens were further analyzed by PAGE and G/P-genotyped by multiplex semi-nested RT-PCR. RESULTS: Rotaviruses were detected in 323 stool samples over 1503 (21 %). Long electropherotypes predominated in Tunisia during the whole period of study (N=158 vs N=82 short electropherotypes). VP7 genotyping showed the cocirculation of five different genotypes: G1, G2, G3, G4 and G9. VP4 typing detected four different P-genotypes: P[8], P[4], P[6] and P[11]. Rotavirus strains with G3P[8] specificity were predominating in Tunisia in 2005 and 2006, replaced by G2P[4] strains in 2007.

Considerations for introduction of a rotavirus vaccine in Oman: rotavirus disease and economic burden.

Rotavirus is the most common cause of fatal childhood diarrhea worldwide. We provide the first estimates of the health care and economic burden of severe rotavirus disease in Oman. We conducted active, hospital-based surveillance of rotavirus disease at 11 regional public hospitals in Oman, using the guidelines suggested by the generic World Health Organization protocol. From July 2006 through June 2008, all children aged <5 years who were hospitalized for acute gastroenteritis were enrolled in the surveillance program, and their stool samples were tested for rotavirus using a commercially available enzyme immunoassay (ID EIA Rotavirus Test; Dako Diagnostics). Rotavirus was detected in samples from 1712 (49%) of 3470 children. These children were hospitalized for a median of 3 days for severe diarrhea. A marked seasonal peak was evident with a majority of the cases occurring from December through May. Of the rotavirus cases, 69% occurred in children aged 6-17 months. We identified a diverse strain pattern in Oman, with G2 (37%), G1 (38%), and G9 (11%) accounting for most of typeable strains. By our burden estimates, the Omani government spends an estimated US$791,817 and US$1.8 million annually to treat rotavirus-associated diarrhea in the outpatient and hospital settings, respectively. A rotavirus vaccination program might substantially reduce the burden of severe diarrhea among children in Oman.

Sentinel hospital-based surveillance of rotavirus diarrhea in iran.

BACKGROUND: Rotavirus is the most common causes of severe, acute diarrhea during childhood and is an important cause of morbidity and mortality in developing countries. We established active hospital-based surveillance of childhood diarrhea to assess the scope of severe rotavirus disease in Iran. METHODS: From May 2006 through April 2007, prospective surveillance of rotavirus diarrhea among children aged <5 years was conducted in 5 sentinel hospitals in Iran. Stool samples were tested for rotavirus using a commercially available enzyme immunoassay, and rotavirus-positive samples were genotyped using reverse-transcriptase polymerase chain reaction. RESULTS: Of 2198 children admitted to the hospital for acute gastroenteritis, 1298 (59.1%) had stool samples test positive for rotavirus by enzyme immunoassay. Of the rotavirus episodes, 85% occurred during the first 2 years of life, with the peak prevalence of severe rotavirus disease occurring from September through January. Among the 110 rotavirus-positive samples that were genotyped, G4P[8] was the most commonly detected rotavirus genotype (30.9% of strains). Other commonly detected genotypes included P[8] with G nontypeable (21.8%), G4 with P nontypeable (13.6%), G1[P8] (10.9%), and G2[P4] (5.5%). CONCLUSIONS: Rotavirus is the most common cause of severe diarrhea in Iran, which indicates that safe and effective rotavirus vaccination in Iran is a public health priority.

Knowledge and perception of professionals towards school injuries.

As injuries remain a threat to children everywhere including school, this study was undertaken to reveal the knowledge and perceptions of school physicians, nurses, teachers and social workers regarding school injuries. To accomplish this aim, all school-based clinics operated by a physician were identified. All physicians and nurses were included in this survey. In addition, a teacher or a social worker was randomly selected from the same school. They were requested to fill in a questionnaire to collect relevant information. Findings indicate that school injury is not perceived as a priority problem by all social workers and 68.5% of teachers. Moreover, its economic burden was not perceived by one third of physicians and nurses. Regarding associated risk factors, more than 80% of the surveyed professionals recognized nine out of the 16 stated factors as a risk for school injuries. However, less than 80% viewed that the risk of school injury is higher in technical schools, schools which include more than one educational stage as well as in the evening shift. Moreover, less than 80% of nurses recognized that a higher risk is associated with poorly kept school building, primary schools and methods of transportation. Furthermore, less than 80% of teachers recognized that boys are at a much higher risk of injuries. Surveyed professionals ranked increase supervision, continuous maintenance of school building as well as health education activities as priority preventive strategies. Mass media was the method of health education that received the highest priority while the least were pupils' activities and the organization of an injury prevention day. It can be concluded that, school professionals, exceptionally teachers and social workers need to be aware of the extent of school injuries and the risks associated with their occurrence. Such awareness is the key issue in ensuring the safety of children while they are at school. Moreover, it is indispensable for the planning and implementation of effective preventive strategies. They should also recognize that pupils' involvement is a highly effective mean of creating awareness about safety and to encourage them to take the responsibility of their safety as well as that of other pupils. Organized training programs directed to all personnel in the area of school injuries are deemed essential.

Epidemiology of school injuries in Alexandria.

This study was conducted to reveal the magnitude of school injuries in Alexandria, their epidemiological patterns and outcomes. All pupils attending the casualty department of Alexandria Students' Hospital during the scholastic year 1996-1997 with school injuries were included in this study. An interview questionnaire and a transfer sheet were used to collect relevant information. Data were analyzed and the 5% level was taken to judge the significance of the obtained results. During the study period, 3422 pupils sustained school injuries yielding a rate of 4.25 per 1000. This rate was significantly higher among boys (6.43 per 1000) as well as in secondary schools (8.11 per 1000). Most of these injuries occurred inside the school (72.0%). In relation to school activity, injuries occurred more frequently during breaks (28.1%), school trips (27.8%) and teaching sessions (25.6%). Falls were responsible for 52.3% of the injuries followed by struck by or against (25.2%), while 11.9% were due to road traffic accidents. The most commonly affected sites were the upper (46.2%) and lower (32.1%) limbs as well as the head and neck (16.6%). High proportions of the resulting injuries were minor, however, severe injuries namely, fractures (23.2%) and brain concussions (2.8%) were encountered. Significant differences were observed in this respect in relation to the pupils' gender and educational stage. Only 12.5% of the cases were hospitalized. All recovered completely except four cases of leg amputation and no deaths were recorded. School injuries appear to be a priority area for primary preventive activities. School personnel should receive safety rounds to recognize the potential environmental hazards. Stringent supervision is required in areas and during activities with high frequency of injuries. Moreover, safety education should be incorporated in the curriculum and activities involving school children.