University of Jordan

About: University of Jordan is a education organization based out in Amman, Jordan. It is known for research contribution in the topics: Population & Health care. The organization has 7796 authors who have published 13764 publications receiving 213526 citations.

The Gulf of Aqaba earthquake swarm of 1983 January‐April

Abstract: Summary. In the period 1983 January 21 -April 20, more than 500 local earthquakes (ML≤ 4.85) occurred in the Gulf of Aqaba area between latitudes 29°00′and 29°25′and longitudes 34°30′and 34°45′. Most of the activity including the largest shocks was restricted to the area between latitudes 29°07′and 29° 15′and longitudes 34°33′and 34°42′where the NW Atiya regional dyke crosses the area and is horizontally displaced by NE strike-slip faults. The first-motion directions of four large shocks, including the largest, at both UNJ and HLW stations are in agreement with a strike-slip mechanism at a NE-trending fault in this area. The b value showed a temporal increase with time from 0.43 to 0.69. This, together with other geological and geophysical observations may indicate that subsurface magmatic activity has affected the stressed crustal rocks, thus triggering earthquake activity. This swarm and historical information indicate that the Gulf of Aqaba-Dead Sea Jordan transform is characterized by both swarm and foreshock-aftershock types of seismic activity and therefore the relatively large proportion of non-seismic slip along the southern part of this transform may actually be higher if swarm-type activities are considered.

A factor found in the IgG fraction of serum of patients with paraneoplastic bilateral diffuse uveal melanocytic proliferation causes proliferation of cultured human melanocytes.

Abstract: Purpose To determine if there is a factor in the serum of patients with bilateral diffuse uveal melanocytic proliferation (BDUMP) that causes melanocytic proliferation. Methods Human melanocytes and melanoma cells were grown and exposed to serum or plasma of patients with BDUMP, other neoplastic conditions, or control media. Preliminary studies using serum were conducted in an unmasked fashion. In addition, IgG-depleted and IgG-enriched plasma was also tested in a similar fashion. Experiments using plasma were conducted triple masked. To show that the proliferation was melanocyte selective, human dermal fibroblasts, keratinocytes, and ovarian cancer cells were treated with plasma of the BDUMP cases or controls, and the effect of this exposure on their proliferation was quantified. Results At 72 hours, the serum of BDUMP patients caused statistically significant increased proliferation of normal human melanocytes. Further studies at 6 days demonstrated similar findings. In addition, melanocytes grown in BDUMP serum exhibited a disorganized morphology with foci of multilayered cells. Cultured melanoma cells also showed statistically significant increase in growth in serum from BDUMP patients compared with controls. Masked plasma studies further confirmed these findings and showed that the IgG fraction appeared to contain the melanocyte growth-stimulating factor. The human fibroblasts, keratinocytes, and ovarian cancer cells did not show an increase in growth with the BDUMP plasma treatment. Conclusion Patients with BDUMP have a factor in the IgG fraction that selectively causes melanocyte proliferation. How it causes proliferation of human melanocytes and melanoma cells needs to be further elucidated.

Physical factors controlling abundance of meiofauna on tidal and atidal beaches

Abstract: Quantitative samples of interstitial sand beach meiofauna were collected from Morocco along the North African coast (Algeria and Tunisia) and northwards to Lebanon, Turkey and Cyprus. Data on the sediment median diameter, sorting coefficient and beach temperature were used to construct multiple-regression equations relating these factors to the total meiofaunal numbers. Curvilinear regression was found to give a significantly better fit than linear regression in all cases but one. Treating the whole Mediterranean data, the equation explained 9.3% of the variance in meiofaunal abundance. Within narrower geographical areas, however, the equations explained significantly more of the variance: 56.70% of Moroccan tidal beach data, 75.60% of South Tunisian tidal beach data, and 62.3% of South Tunisian atidal beach data. For the tidal beach equations sorting was the most important factor, followed by temperature and median diameter. It is suggested that the factors controlling meiofaunal abundance on these beaches are likely to be wave, tide and current action which also control sorting. The lack of fit of most atidal beach data suggests that here biological interactions such as competition and predation may control meiofaunal abundance. The detection of beaches affected by pollutants may also be possible using regression techniques. Beaches having a significantly enriched population (sewage-induced) or depleted population (pollutant-induced) can be readily detected.

Pharmacophore Modeling, Quantitative Structure−Activity Relationship Analysis, and Shape-Complemented in Silico Screening Allow Access to Novel Influenza Neuraminidase Inhibitors

Abstract: Neuraminidase (NA) enzyme is one of the valid targets against influenza viruses. With this in mind, the pharmacophoric space of influenza NA was explored using three sets of diverse inhibitors. Subsequently, genetic algorithm and multiple linear regression analysis were employed to select optimal combinations of pharmacophoric models and 2D descriptors capable of yielding self-consistent and predictive quantitative structure−activity relationships (QSARs) against 181 training compounds. The optimal QSAR equations were validated against 43 external test compounds with r2PRESS values ranging from 0.488 to 0.591. Interestingly, five orthogonal pharmacophores emerged in the optimal QSAR equations suggesting the existence of several distinct ligand/NA binding modes within the NA binding pocket. The resulting pharmacophores were complemented with tight shape constraints and employed as three-dimensional (3D) search queries against the National Cancer Institute (NCI) list of compounds. Several hits exhibited pot...

The Effect of Polishing Technique on 3-D Surface Roughness and Gloss of Dental Restorative Resin Composites

Abstract: Clinical Relevance This article discusses the surface finish of different modern types of composites polished using different polishing protocols used in all dental practices.