Limnological investigations on the Rosetta branch of the Nile. I. Environmental conditions

SUMMARY.

• 1 Seasonal and local variations of some environmental conditions in the Rosetta branch of the River Nile are reported. The lowest air and water temperatures were recorded in January (winter) and the highest in July (summer). Slight decrease in water temperatures with depth is related to solar heating and mixing processes. The pH values, averaging between pH 7.5 and 8.2, showed seasonal changes which, in the main, may be related to photosynthesis.
• 2 The seasonal average chlorosity values showed very wide variation, due to fluctuations in the discharge rate of the River Nile and its effect on the estuarine sea water. Sharp increase in chlorosity values with depth at the estuarine stations was produced by the less dense river water, flowing over denser tongues of sea water. In January, however, the maximum discharge flushed out the sea water.
• 3 Minimum oxygen saturation values occurred in January and the highest values of dissolved organic matter were obtained in July. Both of these will be shown in a later publication to be related to phytoplankton abundance. Increase in dissolved organic matter near the bottom was common and is interpreted as due to the more complete decomposition of descending dead organisms and the release of organic matter from the bottom deposits.

     

Spatio-temporal Processes in a Calcareous Grassland

Abstract The herbaceous plant communities occurring on nutrient-poor calcareous soils of north-western Europe are typically rich in species, with as many as 30–40 species m^-2. It is an open question as to what dynamic properties allow this diversity. We review evidence that we have collected on the spatial and temporal processes operating in a calcareous grassland community in England to address this issue. Our data indicate spatial aggregation of individuals within species consistent with the modular growth of the species concerned, but there is little evidence to suggest spatial structure generated by interactions between species, and we have been unable to separate most species tested into different niches. The development of spatial structure of the community through time is also consistent with dynamics that depend principally on the modular growth patterns of the different species. We suggest that there is a nonlinearity in the per capita rate of increase with the property that the community is no more than weakly dependent on densities of the species under natural conditions. The dynamic of the community is then driven more by forces external to the community than by density-dependent effects within the community.     

Limnological investigations on the Rosetta branch of the Nile. III. Phytoplankton

SUMMARY.

• 1 Seasonal qualitative and quantitative studies of the phytoplankton of the Rosetta branch of the River Nile are reported. Most of the genera were Bacillariophyceae, with Chlorophyceae and Cyanophyceae second and third. Only two genera of Dinophyceae were present. The phytoplankton can be broadly described as eurythermal and euryhaline.
• 2 Phytoplankton tended to be more concentrated in surface waters and showed large variations from station to station, with noticeably lower values in the estuarine region except in January.
• 3 Most of the genera were recorded at all times but seasonally the highest numbers of diatoms and green algae were found in July during a period of high temperature and low discharge whereas blue-greens achieved maximum density in October.

     

Association of interleukin-10 (A1082G) gene polymorphism with oral squamous cell carcinoma in north Indian population

The functional polymorphism A1082G in the gene (IL10) for interleukin-10 associated with risk of oral squamous cell carcinoma (OSCC). The present case–control study was to evaluate the possible association between IL10 A1082G gene and OSCC in north Indian population. Analysis of IL10 A1082G genotype in 232 OSCC cases and 221 healthy controls of comparable age, gender, smokers, tobacco chewing and alcohol consumption. IL10 A1082G status in cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The frequencies of IL10 A1082G polymorphism AA, AG, GG genotypes were 29.74, 68.10 and 2.15% in OSCC cases and 57.46, 42.08 and 0.45% in healthy controls. The average frequency of G mutant allele was 36.20% in OSCC cases compared with 21.50% among the controls and this allele was associated with increased risk for OSCC cases. Heterozygous AG genotype was found statistically significant in OSCC cases than in controls (OR = 1.6, 95% CI = 1.1–2.2, P = 0.003), whereas homozygous mutant GG genotype was not found significant (OR = 4.7, 95% CI = 0.55–41.1, P = 0.2). Moreover, we found that G allele was significant in OSCC cases of tobacco chewing. The frequency of IL10 A1082G polymorphism G allele and AG genotype is associated with OSCC cases as compared with controls; this may be due to smoking and tobacco chewing. Our findings showed that in IL10 A1082G gene polymorphism AG genotype and G allele may participate in the progression of OSCC.     

Limnological investigations on the Rosetta branch of the Nile. II. Seasonal variations of nutrients

SUMMARY.

• 1 Nitrate tended to be low in the estuarine region compared with the freshwater stretches and seasonally was low in October. Nitrite broadly showed patterns similar to NO₃ but at lower values.
• 2 Reactive phosphate and silicate tended to be much higher in fresh compared with saline stretches and was high in January.
• 3 These changes are broadly interpreted in relation to river discharge and the seasonality of phytoplankton although other, and as yet unstudied, causes will probably be found to be involved.

     

Two new species of Linaria section Linaria (Scrophulariaceae‐Antirrhineae) from Iran

Linaria azerbaijanensis and Linaria shahroudensis are described as new species from the Azerbaijan and Semnan provinces of Iran, respectively, belong to section Linaria.The new species are compared to their closest relative Linaria lineolata. Linaria azerbaijanensis differs from L. lineolata in having shorter bracts, a shorter corolla, shorter spur and smaller capsules and a different microsculpturing pattern of the testa cells. Linaria shahroudensis differs from L. lineolata in having shorter stems, shorter calyx‐lobes, a longer spur, a smaller capsule and a different microsculpturing pattern of the testa cells. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 734–742.     

The prevalence and correlates of DSM-IV disorders in the Iraq Mental Health Survey (IMHS)

Data on the prevalence and correlates of anxiety, mood, behavioral, and substance disorders are presented from a 2007-8 national survey of the Iraq population, the Iraq Mental Health Survey (IMHS). The IMHS was carried out by the Iraq Ministry of Health in collaboration with the Iraq Ministry of Planning and the World Health Organization (WHO) World Mental Health (WMH) Survey Initiative. Interviews were administered to a probability sample of Iraqi household residents by trained lay interviewers. The WHO Composite International Diagnostic interview (CIDI) was used to assess DSM-IV disorders. The response rate was 95.2%. The estimated lifetime prevalence of any disorder was 18.8%. Cohort analysis documented significantly increasing lifetime prevalence of most disorders across generations. This was most pronounced for panic disorder and post-traumatic stress disorder, with lifetime-to-date prevalence 5.4-5.3 times as high at comparable ages in the youngest (ages 18-34) as oldest (ages 65+) cohorts. Anxiety disorders were the most common class of disorders (13.8%) and major depressive disorder (MDD) the most common disorder (7.2%). Twelve-month prevalence of any disorder was 13.6%, with 42.1% of cases classified mild, 36.0% moderate, and 21.9% serious. The disorders most often classified serious were bipolar disorder (76.9%) and substance-related disorders (54.9%). Socio-demographic correlates were generally consistent with international epidemiological surveys, with the two exceptions of no significant gender differences in mood disorders and positive correlations of anxiety and mood disorders with education. Only 2.2% of IMHS respondents reported receiving treatment for emotional problems in the 12 months before interview, including 23.7% of those with serious, 9.2% with moderate, and 5.3% with mild disorders and 0.9% of other respondents. Most healthcare treatment, which was roughly equally distributed between the general medical and specialty sectors, was of low intensity. Further analyses of barriers to seeking treatment are needed to inform government efforts to expand the detection and treatment of mental disorders