The study explored and discussed the water management strategy of Istanbul with more than 16 million inhabitants. Istanbul has quite limited local fresh water resources with an ultimate storage ...capacity of 868.7 million m
3
and supplies daily approximately 2.8 million m
3
of water at a magnitude of 180 L/ca. 36% of the water demand is supplied from a water source 190 km away from the city. In this study, the critical balance was evaluated accounting for all important factors, population, expansion; water demand; water quality; protection of water resources. The evaluation was specifically conducted in two major water catchment areas around Büyükçekmece and Ömerli Basins between 1994 and 2019 using remote sensing technology. The results outlined a significant increase mainly from bare land and green area to artificial surface in Büyükçekmece and Ömerli Basins with a rate of 217% and 77%, respectively. The conversions to artificial surface were mostly observed to occur in long-range protection zones in both basins. This study also interpreted the potential impacts of the proposed “Canal Project” on water resources regarding the existing and future demands of the population living in Istanbul. The quantitative and qualitative evaluations outlined the fact that the following 5 years of Istanbul will be a critical period in terms of survival and collapse of water management, and that Istanbul needs to enrich its local water resources by generating other alternatives, i.e. sea water desalination from Black Sea or Marmara Sea to compete with the increase of population.
Using the shallow water equations for a rotating layer of fluid, the wave and dispersion equations for Rossby waves are developed for the cases of both the standard β-plane approximation for the ...latitudinal variation of the Coriolis parameter f and a zonal variation of the shallow water speed. It is well known that the wave normal diagram for the standard (mid-latitude) Rossby wave on a β-plane is a circle in wave number (ky,kx) space, whose centre is displaced −β/2 ω units along the negative kx axis, and whose radius is less than this displacement, which means that phase propagation is entirely westward. This form of anisotropy (arising from the latitudinal y variation of f), combined with the highly dispersive nature of the wave, gives rise to a group velocity diagram which permits eastward as well as westward propagation. It is shown that the group velocity diagram is an ellipse, whose centre is displaced westward, and whose major and minor axes give the maximum westward, eastward and northward (southward) group speeds as functions of the frequency and a parameter m which measures the ratio of the low frequency-long wavelength Rossby wave speed to the shallow water speed. We believe these properties of group velocity diagram have not been elucidated in this way before. We present a similar derivation of the wave normal diagram and its associated group velocity curve for the case of a zonal (x) variation of the shallow water speed, which may arise when the depth of an ocean varies zonally from a continental shelf.
Abstract
Study question
Influence of sperm selector separation of sperms on their translocation load, segregation pattern, motility and occurrence of interchromosomal effects
Summary answer
Sperm ...selector separation led to reduction of the translocation load, shift in segregation pattern and lower rates of interchromosomal effects within sperm samples
What is known already
Balanced translocations in men are known to be one of the main causes of reproductive failure. The segregation pattern in sperms is determined by the distribution of the chromosomes during meiosis. Interchromosomal effects can also influence the distribution of chromosomes that are not involved in the translocation. The sperm selector used consists of two concentric chambers, which are overlaid by a U-ring and a cover glass. Motile sperms migrate from the native ejaculate in the medium filled inner chamber by using a capillary bridge created by the U-ring. This avoids potential harmful centrifugation and allows accumulation of motile sperms.
Study design, size, duration
Twenty-one carriers of balanced translocations participated in the study. In addition, 15 patients were involved as control. All participants signed an informed consent (F–8–15). Samples of three patients did not meet the internal quality criteria and had to be excluded from analysis. The study started in 2015 and is still ongoing.
Participants/materials, setting, methods
Liquefied native ejaculate was processed with a sperm selector. Native ejaculate, non-migrated sperms from the outer chamber and migrated sperms from the inner chamber were transferred onto glass slides, fixed and underwent a decondensation treatment. For segregation analysis FISH translocation specific FISH probe mixes were used and tested on patient’s blood. Interchromosomal effects were analysed with FISH probes for the chromosomes X, Y, 18 and 13, 21. Evaluation was done manually using fluorescence microscopy.
Main results and the role of chance
Segregation analysis was done for more than 25,000 sperms from men carrying a balanced translocation (18 patients with reciprocal and 3 patients with Robertsonian translocation). Separation via sperm selector led to a reduction in translocation load (native to separated approach 49,1±11,5% to 34,8±9,4% (P = <0,01), the rate depending on the specific translocation. There was also a shift in the segregation pattern, which seemed to be influenced by the specific translocation and the resulting steric alignment of the corresponding quadrivalent / trivalent. Additionally, more than 90,000 sperms from patients with balanced translocations were analysed for interchromosomal effects. Separation led to reduced maldistribution rate (native to separated approach 7,1±3,5% to 5±3,1%, P = <0,01) whereas the steric alignment of the corresponding quadrivalent / trivalent seems to influence the interchromosomal effect as well. For control, sperms from control patients were analysed regarding the chromosomes X, Y, 18 and 13, 21. In about 90,000 control sperms separation led to reduced maldistribution rate (native to separated approach 5,4±1,5% to 3,8±1,1%; P = <0,01).
Limitations, reasons for caution
The number of accumulated strandbreak-free sperms depended on the motility and sperm count of the native ejaculate. Examinations are not reproducible, as each sample delivery is influenced by external circumstances
Wider implications of the findings: Sperm selector separation can be used before ART to reduce the translocation load and rate of maldistribution in sperms from carriers of balanced translocations. This could have a considerable impact on PGT results after trophectoderm biops.
Trial registration number
Not applicable
Road traffic accidents (RTAs) are a major cause of death and injury globally. There was little information on the burden and causes of RTAs in Bhutan. The study estimates the burden and ...characteristics of RTAs and describes the victims of RTAs in Bhutan. A descriptive cross-sectional study conducted analysing police case records. In 2013-2014, 1866 accidents resulted in 1143 injuries and 157 deaths. We identified 39% more deaths from RTAs than that submitted to WHO in 2013 as the 30-day mortality. The main causes were careless driving and drunk-driving. Drivers and passengers constituted 86% of the deaths with few pedestrian deaths. Data for in-hospital deaths or after discharge were not available. Productivity loss due to RTA is around 1% of national GDP. There is significant mortality and morbidity from RTAs in Bhutan. There is no coordinated system for data collection and surveillance to monitor SDG goal 3.6.
The genetic basis for addiction to tobacco smoking—particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction—is largely unknown. A cluster of ...genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14–4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers odds ratio: 4.97 (1.96–12.62); P = 0.001, and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking.
We have performed three searches for high-frequency signals in the solar neutrino flux measured by the Sudbury Neutrino Observatory, motivated by the possibility that solar g-mode oscillations could ...affect the production or propagation of solar {sup 8}B neutrinos. The first search looked for any significant peak in the frequency range 1-144 day{sup -1}, with a sensitivity to sinusoidal signals with amplitudes of 12% or greater. The second search focused on regions in which g-mode signals have been claimed by experiments aboard the Solar and Heliospheric Observatory satellite, and was sensitive to signals with amplitudes of 10% or greater. The third search looked for extra power across the entire frequency band. No statistically significant signal was detected in any of the three searches.
Using linear and weakly nonlinear stability theory, the effects of Soret and Dufour parameters are investigated on thermohaline convection in a horizontal layer of rotating fluid, specifically the ...ocean. Thermohaline circulation is important in mixing processes and contributes to heat and mass transports and hence the earth's climate. A general conception is that due to the smallness of the Soret and Dufour parameters their effect is negligible. However, it is shown here that the Soret parameter, salinity and rotation stabilise the system, whereas temperature destabilises it and the Dufour parameter has minimal effect on stationary convection. For oscillatory convection, the analysis is difficult as it shows that the Rayleigh number depends on six parameters, the Soret and Dufour parameters, the salinity Rayleigh number, the Lewis number, the Prandtl number, and the Taylor number. We demonstrate the interplay between these parameters and their effects on oscillatory convection in a graphical manner. Furthermore, we find that the Soret parameter enhances oscillatory convection whereas the Dufour parameter, salinity Rayleigh number, the Lewis number, and rotation delay instability. We believe that these results have not been elucidated in this way before for large-scale fluids. Furthermore, we investigate weakly nonlinear stability and the effect of cross diffusive terms on heat and mass transports. We show the existence of new solution bifurcations not previously identified in literature.
James Fairley McKenzie, who was a professor of applied mathematics at the University of Natal from 1981 to 1998, would have been 80 in May 2018. A Special Session was held in his honour at the Annual ...Congress of the South African Mathematical Society at Rhodes University in December 2018. At the Special Session his career in research and teaching was outlined, appreciations by his former PhD students and the early career academics he mentored were made, papers in the areas of research to which he and his students had contributed were presented, and his legacy in research, supervision and mentoring was assessed. A summary of the Special Session is presented in this paper.
The central role of chemokines in the pathogenesis of atherosclerosis has been made clear. Recently polymorphisms in the gene regulatory region of MCP-1 and in the promoter region of RANTES have been ...found, which increase the expression of these chemokines. We investigated the role of these polymorphisms together with the chemokine SDF-1−801A and the chemokine receptors CCR2-64I and CCR5Δ32 mutations in 318 patients with coronary artery disease (CAD) referred to coronary bypass surgery, comparing them with 320 healthy controls. The prevalence of the MCP-1 −2518 G/G homozygotes was significantly higher among CAD patients than among controls (
P<0.005; OR=2.2 (95% CI 1.25–3.92). The Lp(a) levels of CAD patients with G/G genotype were significantly higher than those in patients with G/A or A/A genotypes. No CAD patients homozygous for the CCR5Δ32 and CCR2-64I mutations have been found. The genotype distributions of the two alleles deviated from the Hardy Weinberg equilibrium in patients, indicating that the numbers of homozygotes were significantly lower than expected. The MCP-1 −2518G variant in homozygous form appears as a genetic risk factor for severe CAD. This genotype is associated with elevated Lp(a) levels in patients. Individuals homozygous for CCR2-64I or CCR5Δ32 mutations are at reduced risk for severe CAD.
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