3,332 research outputs found
Morphology of Tigris River within Baghdad City
In recent years, substantial changes have occurred in the morphology of the River Tigris within Baghdad City. Although huge volumes of sediment are being trapped in recently constructed headwater reservoirs, the number of islands in the Tigris at Baghdad is increasing. The debris of bridges destroyed in the wars of 1991 and 2003 and their subsequent reconstruction have enhanced the development of these islands. As a consequence the ability of the river to carry the peaks of flood waters has been reduced. This has led to potential increase of flooding in parts of the city. <br><br> The bed of the River Tigris has been surveyed on three occasions (1976, 1991, and 2008). The most recent survey was conducted by the Ministry of Water Resources, extended 49 km from the Al-Muthana Bridge north Baghdad to the confluence with the Diyala River south Baghdad. It yielded cross-section profiles at 250 m intervals. The data are used to predict the maximum flood capacity for the river using the one-dimensional hydraulic model for steady flow "HEC-RAS" modeling. Calibration of the model was carried out using field measurements for water levels along the last 15 km of the reach and the last 10 yr of observation at the Sarai Baghdad gauging station. <br><br> The model showed a significant predicted reduction in the current river capacity below that which the river had carried during the floods of 1971 and 1988. The three surveys conducted on the same reach of the Tigris indicated that the ability of the river to transport water has decreased
Constrained Statistical Modelling of Knee Flexion from Multi-Pose Magnetic Resonance Imaging
© 1982-2012 IEEE.Reconstruction of the anterior cruciate ligament (ACL) through arthroscopy is one of the most common procedures in orthopaedics. It requires accurate alignment and drilling of the tibial and femoral tunnels through which the ligament graft is attached. Although commercial computer-Assisted navigation systems exist to guide the placement of these tunnels, most of them are limited to a fixed pose without due consideration of dynamic factors involved in different knee flexion angles. This paper presents a new model for intraoperative guidance of arthroscopic ACL reconstruction with reduced error particularly in the ligament attachment area. The method uses 3D preoperative data at different flexion angles to build a subject-specific statistical model of knee pose. To circumvent the problem of limited training samples and ensure physically meaningful pose instantiation, homogeneous transformations between different poses and local-deformation finite element modelling are used to enlarge the training set. Subsequently, an anatomical geodesic flexion analysis is performed to extract the subject-specific flexion characteristics. The advantages of the method were also tested by detailed comparison to standard Principal Component Analysis (PCA), nonlinear PCA without training set enlargement, and other state-of-The-Art articulated joint modelling methods. The method yielded sub-millimetre accuracy, demonstrating its potential clinical value
Prospects for Improving the Intrinsic and Extrinsic Properties of Magnesium Diboride Superconducting Strands
The magnetic and transport properties of magnesium diboride films represent
performance goals yet to be attained by powder-processed bulk samples and
conductors. Such performance limits are still out of the reach of even the best
magnesium diboride magnet wire. In discussing the present status and prospects
for improving the performance of powder-based wire we focus attention on (1)
the intrinsic (intragrain) superconducting properties of magnesium diboride,
Hc2 and flux pinning, (2) factors that control the efficiency with which
current is transported from grain-to-grain in the conductor, an extrinsic
(intergrain) property. With regard to Item-(1), the role of dopants in Hc2
enhancement is discussed and examples presented. On the other hand their roles
in increasing Jc, both via Hc2 enhancement as well as direct
fluxoid/pining-center interaction, are discussed and a comprehensive survey of
Hc2 dopants and flux-pinning additives is presented. Current transport through
the powder-processed wire (an extrinsic property) is partially blocked by the
inherent granularity of the material itself and the chemical or other
properties of the intergrain surfaces. These and other such results indicate
that in many cases less than 15% of the conductor's cross sectional area is
able to carry transport current. It is pointed out that densification in
association with the elimination of grain-boundary blocking phases would yield
five-to ten-fold increases in Jc in relevant regimes, enabling the performance
of magnesium diboride in selected applications to compete with that of Nb-Sn
Molecular epidemiology and genotype distribution of Human Papillomavirus (HPV) among Arab women in the state of Qatar
Background: Human Papilloma Virus (HPV) infection is the major cause of cervical cancer worldwide.
With limited data available on HPV prevalence in the Arab countries, this study aimed to
identify the prevalence and genotypic distribution of HPV in the State of Qatar.
Methods: 3008 cervical samples, exclusively of women with Arabic origin residing in Qatar were
collected from the Women’s Hospital and Primary Health Care Corporation in Doha, State of
Qatar. HPV DNA detection was done using GP5+/6+ primers based real time-polymerase
chain reaction (RT-PCR) assay followed by the usage of HPV type specific primers based
RT- PCR reactions and Sanger sequencing for genotype identification.
Results: Similar prevalence rates of HPV infection was identified in both Qatari and non-Qatari
women at 6.2% and 5.9% respectively. HPV prevalence rate of 5.8% and 18.4% was
identified in women with normal cytology and in women with abnormal cytology
respectively. HPV 81, 11 and 16, in decreasing order were the most commonly identified
genotypes. HPV 81 was the most frequent low-risk genotype among women with both
normal (74.0%) and abnormal (33.3%) cytology. HPV 16 (4.6%) was identified as the
predominant high-risk HPV genotype among women with normal cytology and HPV 16,
HPV 18, and HPV 56 (22.2% each) were the most common identified high-risk genotypes in
women with abnormal cytology
Conclusions: The overall HPV prevalence in Arab women in Qatar was identified as 6.1% with an
increased HPV prevalence seen in women with abnormal cytology results and no significant
trends seen with age. In contrast to Western countries, we report a varied genotypic profile of
HPV with a high prevalence of low-risk HPV genotype 81 among the Arab women residing
in Qatar.Weill Cornell Medical College in Qatar; and by a grant from the Qatar National Research Fund (NPRP- 09-344-3-082)
Internet-based search of randomised trials relevant to mental health originating in the Arab world
BACKGROUND:
The internet is becoming a widely used source of accessing medical research through various on-line databases. This instant access to information is of benefit to busy clinicians and service users around the world. The population of the Arab World is comparable to that of the United States, yet it is widely believed to have a greatly contrasting output of randomised controlled trials related to mental health. This study was designed to investigate the existence of such research in the Arab World and also to investigate the availability of this research on-line.
METHODS:
Survey of findings from three internet-based potential sources of randomised trials originating from the Arab world and relevant to mental health care.
RESULTS:
A manual search of an Arabic online current contents service identified 3 studies, MEDLINE, EMBASE, and PsycINFO searches identified only 1 study, and a manual search of a specifically indexed, study-based mental health database, PsiTri, revealed 27 trials.
CONCLUSION:
There genuinely seem to be few trials from the Arab world and accessing these on-line was problematic. Replication of some studies that guide psychiatric/psychological practice in the Arab world would seem prudent
A systematic review of randomised controlled trials on the effectiveness of exercise programs on lumbo pelvic pain among postnatal women
Background: A substantial number of women tend to be affected by Lumbo Pelvic Pain (LPP) following child birth.
Physical exercise is indicated as a beneficial method to relieve LPP, but individual studies appear to suggest mixed
findings about its effectiveness. This systematic review aimed to synthesise evidence from randomised controlled trials on the effectiveness of exercise on LPP among postnatal women to inform policy, practice and future research.
Methods: A systematic review was conducted of all randomised controlled trials published between January 1990 and July 2014, identified through a comprehensive search of following databases: PubMed, PEDro, Embase, Cinahl, Medline, SPORTDiscus, Cochrane Pregnancy and Childbirth Group’s Trials Register, and electronic libraries of authors’institutions.
Randomised controlled trials were eligible for inclusion if the intervention comprised of postnatal exercise for women
with LPP onset during pregnancy or within 3 months after delivery and the outcome measures included changes in
LPP. Selected articles were assessed using the PEDro Scale for methodological quality and findings were synthesised narratively as meta-analysis was found to be inappropriate due to heterogeneity among included studies.
Results: Four randomised controlled trials were included, involving 251 postnatal women. Three trials were rated as
of ‘good’ methodological quality. All trials, except one, were at low risk of bias. The trials included physical exercise
programs with varying components, differing modes of delivery, follow up times and outcome measures. Intervention
in one trial, involving physical therapy with specific stabilising exercises, proved to be effective in reducing LPP
intensity. An improvement in gluteal pain on the right side was reported in another trial and a significant difference in
pain frequency in another.
Conclusion: Our review indicates that only few randomised controlled trials have evaluated the effectiveness of
exercise on LPP among postnatal women. There is also a great amount of variability across existing trials in the
components of exercise programs, modes of delivery, follow up times and outcome measures. While there is some
evidence to indicate the effectiveness of exercise for relieving LPP, further good quality trials are needed to ascertain
the most effective elements of postnatal exercise programs suited for LPP treatment
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L1 transfer in the acquisition of manner and path in Spanish by native speakers of English
In this article the authors argue that L1 transfer from English is not only important in the early stages of L2 acquisition of Spanish, but remains influential in later stages if there is not enough positive evidence for the learners to progress in their development (Lefebvre, White, & Jourdan, 2006). The findings are based on analyses of path and manner of movement in stories told by British students of Spanish (N = 68) of three different proficiency levels. Verbs that conflate motion and path, on the one hand, are mastered early, possibly because the existence of Latinate path verbs, such as enter and ascend in English, facilitate their early acquisition by British learners of Spanish. Contrary to the findings of Cadierno (2004) and Cadierno and Ruiz (2006), the encoding of manner, in particular in boundary crossing contexts, seems to pose enormous difficulties, even among students who had been abroad on a placement in a Spanish-speaking country prior to the data collection. An analysis of the frequency of manner verbs in Spanish corpora shows that one of the key reasons why students struggle with manner is that manner verbs are so infrequent in Spanish. The authors claim that scarce positive evidence in the language exposed to and little or no negative evidence are responsible for the long-lasting effect of transfer on the expression of manner
Alcohol: from Mesopotamia to Modern Iraq.
An understanding of alcohol's place in Iraq's history and society can help inform alcohol policy responses in that country and other Muslim majority countries. This article describes the history of alcohol in Iraq from ancient to modern times, with reflection on the challenges facing Iraqi youth today. A search was undertaken to identify peer-reviewed and gray literature that describes alcohol-related practices, norms, and values across the millennia in Iraq. A historical overview is provided of alcohol's use and context, with more detail on recent times. Alcohol was an important commodity in Iraq until the rise of Islam in the seventh century CE. Despite the subsequent Islamic restrictions on alcohol, alcohol remained present in Iraq's society and cultures. Recent studies provide varying descriptions of the prevalence of alcohol consumption, and there are challenges in researching this sensitive topic. External forces shaping alcohol use in Iraq include direct and indirect alcohol promotion, globalized media, and conflict and violence with its associated stress and trauma. Alcohol research and policy development in Iraq must consider the country's unique cultural, religious, historical, and political context. Iraq's youth may be subject to pressures to increase consumption, and thus policies must be informed by an understanding of the complex set of current perspectives and pressures
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