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The article analyses the border descriptions of the land of Karkemis according to the treaty between Suppiluliuma and Sattiwaza (CTH 51). We argue that the toponyms that establish the boundaries of...

An experimental investigation was carried out to assess the removal efficiency of metal oxide nanoparticles from aqueous suspensions via sedimentation and the added benefit of membrane filtration. The study was conducted with aqueous suspensions of TiO2, ZnO, and CeO2 nanoparticles (NPs) of primary size of 10 nm–21 nm. The removal of NPs by gravitational settling was carried out with suspensions that were pretreated via pH adjustment and coagulant addition in order to increase the agglomerate size. Removal efficiencies were as high as 72.3–98.6% for the studied NPs with subsequent ultrafiltration of the remaining suspensions (post sedimentation) enabling essentially complete NP removal.

The JAK2V617F mutation has emerged in recent years as a diagnostic as well as treatment target in patients with polycythemia vera (PV). We analyzed JAK2V617F allele burden (JAK2(V617F)) in a Jewish population with PV. Results were correlated with disease symptoms and complications. Median JAK2(V617F) was 48% and 54% in patients of Ashkenazi and non-Ashkenazi origin, respectively (p =0.75). Higher JAK2(V617F) was seen in patients with imaging-proven splenomegaly (p =0.01). A correlation between JAK2(V617F) and the weekly hydoxyurea dose needed for disease control was found (p =0.043). In addition, a trend for higher allele burden in patients with longer disease duration (p =0.064) and those treated with cytoreductive drugs other than hydroxyurea (p =0.056) was noted. Higher JAK2(V617F) was seen in patients with transformation to myelofibosis (p =0.0001), but not in patients with vascular complications. JAK2(V617F) may assist in prognostic stratification of patients with PV.

Hydrogen-bond molecular capsules of resorcin[4]arenes (1) and pyrogallol[4]arenes (2) attracted much interest in the last decade. It was found, for example, that resorcin[4]arenes form hexameric capsules in non-polar organic solvents that can accommodate both trialkylamines and tetraalkylammonium salts. In search for the bulkiest guest that can be accommodated in the cavity of such capsules we found, with the aid of diffusion NMR, that such guests can interact also with the external surface of the hexameric capsules. Interestingly, monitoring the effect of CD3OD titration on the diffusion coefficients of the different components in such host–guest systems indicates that the interaction of such guests with the external surface of the hexameric capsule is significant and can be found also in case where guest's encapsulation occurs as in the case of trioctylamine (3) and tetraoctylammonium bromide (6). These CD3OD titrations showed also that these interactions are disrupted before the hexamer is disrupted an...

The technical viability of RO desalination technology was demonstrated in the late 1950's by the pioneering work of Sidney Loeb and Srinivasa Sourirajan and a team of researchers at the University of California, Los Angeles (UCLA) led by Professors Joseph McCutchan and Samuel Yuster. Today Reverse osmosis (RO) membrane desalination is a mature process for the production of potable water from seawater and inland brackish water. RO membranes are also now widely used as part of the overall process for the treatment of wastewater for reclamation and reuse for irrigation, industrial, and groundwater recharge applications. RO desalination technology is used worldwide and has made it possible to develop new potable water sources in areas of the world where freshwater water sources are scarce.

Reverse osmosis (RO) water desalination is now well established as a mature water desalination technology. With the current generation of seawater and brackish-water RO membranes, it is now both economically and technically feasible to desalt brackish water and seawater on a large scale. In order to further expand the applications of RO desalting technologies, optimal process conditions must be selected to minimize water production costs associated with energy consumption, membrane replacement costs, chemical usage, and residual brine concentrate management. In the present review, a multi-pronged process-optimization approach for reverse osmosis desalination is presented. A theoretical framework discussed for optimizing energy consumption with and without energy recovery devices (ERDs), considering the impact of membrane replacement and brine management costs. The approach enables quantification of the optimal water recovery of RO desalting, considering various factors including the use of energy recovery...

Hydrogen-bond molecular capsules have attracted much interest in the last decade. In the present paper, we wish to describe new insights obtained from diffusion NMR when studying the self-assembly of resorcin[4]arenes (2), pyrogallol[4]arenes (3) and octahydroxypyridine[4]arenes (4) in solution. These diffusion NMR studies demonstrate that compounds 2 and 3 self-assemble spontaneously into hexameric capsules in organic solvents. For compound 4, both hexameric capsules and dimeric aggregates were identified. Diffusion NMR was found to be very useful in evaluating the relative stability of these capsules as well as in determining the role played by water molecules in the self-assembly of such systems. Moreover, diffusion NMR enabled us to establish whether the self-assembly of these capsules proceeds with self-sorting. We could demonstrate that the hexamers of 3 are more stable than the hexameric capsules of 2 and that the formation of such hexamers proceeds with self-sorting and no hetero-hexamers are form...

To investigate the role of inflammation in acute retinal artery occlusion (RAO).Levels of interleukin (IL)-6, IL-8, and tumor necrosis factor alpha (TNF-alpha) were measured in serum (n = 14) and aqueous humor (AqH) (n = 8) samples from patients with RAO. Findings were compared with 24 age- and disease-matched patients, 10 healthy subjects (serum), and 16 patients undergoing cataract surgery (AqH).Patients who arrived early (within 4-6 hours of occlusion) had higher serum IL-8 and IL-6 levels than controls; the IL-6 level in the AqH was lower than that of controls, while the IL-8 level was higher. In seven patients for whom both serum and AqH samples were available, serum IL-6 levels were higher than their corresponding AqH levels in most patients arriving within 10 hours of occlusion, and AqH IL-8 levels were higher than the corresponding serum levels in all but one. TNF-alpha levels were consistently higher in the serum than in the AqH at all time points.Serum IL-8 and IL-6 and AqH IL-8 are elevated immediately following acute RAO. The early local suppression of IL-6 may be related to ocular immune mechanisms.

This article reviews the emissions, environmental fate and transport, analytical chemistry, uptake and metabolism, toxicology, and human epidemiology of chromium. Chromium is unique among regulated toxic elements in the environment in that different species of chromium, specifically chromium (III) and chromium (VI), are regulated in different ways, in contrast to other toxic elements where the oxidation state is not distinguished. In both industrial and environmental situations chromium (III) and chromium (VI) can inter-convert, with reduction of chromium (VI) to chromium (III) generally being favored in most environmental situations. Chromium released into the air, water, and soil can be transported among the various environmental media through various intermedia transport processes. Once in the environment, chromium can be taken up by human and other ecological receptors. Chromium (III) is generally absorbed through cell membranes albeit to a significantly lesser degree than chromium (VI). Because most ...

Health risk assessments for mercury are subject to uncertainties associated with the prediction of exposure from multiple pathways (air, water, and food). In order to accurately predict multipathway exposure, an understanding of the transport and transformation processes that govern mercury's multimedia distribution is required. Modeling and analysis of multimedia exposure requires knowledge of the physicochemical properties, partition coefficients, and intermedia transport properties of a compound. Although a number of reviews of the behavior of mercury in the environment have been published over the last decade, little attention has been given to the environmental multimedia distribution of mercury and the governing intermedia transfer factors. This review provides a comprehensive evaluation of the chemical and physical processes that govern mercury distribution among the major environmental media. Physicochemical properties, partition coefficients, and intermedia transport parameters that can ...

The ovarian follicle reserve is maintained in a delicate state of homeostasis aimed at preserving the majority of follicles in a dormant state. Key regulatory factors in follicle activation and quiescence include the PI3K/PTEN/Akt signaling pathway in the oocyte, as well as external paracrine inhibitory factors such as anti-Mullerian hormone (AMH) (Fig. 1A). Mice with oocyte-specific deletion of one or more elements in the PI3K/PTEN/Akt pathway, or AMH-knockout mice, exhibit premature activation and rapid depletion of ovarian follicle reserve.1 Figure 1. (A) During normal follicular development, the ovary is in a state of equilibrium. The primordial follicles (PMFs) are under balanced regulation by the PI3K/PTEN/Akt pathway and suppressive factors produced by growing follicles ensure ... Disturbance of ovarian homeostasis has been shown to be a mechanism of follicle loss in the case of iatrogenic ovotoxicity. We recently showed that ovotoxic chemotherapy agent cyclophosphamide (Cy) triggers upregulation of the PI3K pathway, initiating a wave of follicle recruitment and growth and, ultimately, burnout of the ovarian follicle reserve.2 In addition, Cy also induced apoptosis in growing follicles within 24 h of exposure. Co-treatment with immunomodulator, AS101, reduced both apoptosis of growing follicles and activation of the PI3K/PTEN/Akt pathway, thereby reducing follicle activation and loss. We further demonstrated that AMH expression levels (as measured by qRT-PCR) dropped to below control levels as early as 12 h post Cy treatment, reflecting the loss of growing follicles at this time point. AMH levels in Cy-treated ovaries remained lower than control levels up to 3 d post-Cy; however, between 3 and 7 d post treatment, AMH expression in Cy-treated ovaries increased not just to equivalent levels to PBS treated mice, but to twice the relative expression and maintained for at least 14 d post-treatment.3 This increase in AMH levels reflects the increase in early growing follicles as a result of Cy-induced follicle activation. The reduction in AMH expression together with the activation of the PI3K pathway, which occur within 24 h of Cy treatment, combine to create a “window of unregulated growth” of the dormant primordial follicle population. This is a new understanding of the mechanisms of ovotoxicity that carries significant implications, reaching further than cancer treatments. This observation is supported by additional studies that have suggested that primordial follicle activation via the PI3K/PTEN/Akt pathway is also the mechanism behind ovarian follicle loss seen after exposure to a number of other environmental carcinogens and ovotoxins. Of particular interest is the implication of the “burnout” phenomenon for ovarian tissue transplantation. Ovarian tissue cryopreservation is a widely used strategy for fertility preservation in young patients with a high risk of ovarian failure after cancer treatment.4 However, the duration of graft survival following ovarian tissue transplantation is extremely variable, in some cases as short as a few months, largely due to massive loss of primordial follicles that occurs following grafting.5 In addition the vast majority of large follicles in the graft are lost during processing, freezing, and thawing, leaving the ovarian reserve unregulated. Our recent observations on follicle dynamics post-ovarian tissue transplantation show that recovered grafts have higher ratios of growing to total follicles and higher levels of proliferation staining than non-transplanted control tissue, and that this is seen to a greater degree in thinner grafts, which have fewer large follicles.6 This data strongly suggests that ovarian tissue grafts undergo a similar process of follicle activation and “burnout” to that seen following Cy treatment (Fig. 1B). It is likely that the removal of follicles from their normal physiological environment disturbs the ovarian homeostasis. The absence of larger follicles in the ovarian cortical strips in particular results in a decrease in the secretion of inhibitory signaling factor AMH,7 leading to follicle activation. The implications of imbalances in ovarian homeostasis may also extend to the normal physiological state. Age-related changes to the ovarian environmental milieu may have important effects on the regulation of follicle activation. With increasing age, the numbers of all follicles in the ovary decrease, and the decrease in the number of growing follicles results in an age-related decline in AMH levels.8 AMH levels do not only reflect the decline in ovarian follicle reserve, they also indicate a decrease in inhibition exerted on the same population of follicles. This may explain the age-related dynamics of ovarian reserve, which show a fairly constant rate of decline in follicle number until age 35–37, when there is an acceleration of follicle loss. We hypothesize that with age-related reduction in follicle inhibition, follicle activation is accelerated, resulting in increased ovarian follicle loss. In our study, we showed that co-administration of AS101 attenuated follicle burnout via its effect on the PI3k pathway and by reducing apoptosis in growing follicles. This raises the possibility that other agents that act on this crucial activation pathway may have the potential to reduce follicle burnout and preserve ovarian follicle reserve in the face of ovotoxic treatments or ovarian tissue transplantation.

A constitutive diffusion theory for polymer solutions is proposed based on a thermomechanical mixture theory. A general expression for the diffusion flux in a binary polymer-solvent system is presented. It is shown that the current approach is capable of sorting out various complex diffusion phenomena. In particular, the dependence of the diffusion flux on a gradient of a generalized chemical potential emerges naturally by considering the limit of “weak equilibrium”.

During 1977 to 1985 90 patients with large-cell non-Hodgkin lymphoma (diffuse histiocytic or diffuse mixed according to Rapport classification) were treated by the CHOP regimen (cyclophosphamide, doxorubicin, vincristine and prednisone) with a mean follow-up of 41 months. Thirty-four patients were treated with radiation therapy as well. The mean number of CHOP cycles to achieve complete response was 4.0 and the mean total number of cycles was 6.6. For 78 patients it was possible to calculate relative dose intensity (RDI) for each drug and the average RDI. Sixty-four patients (71%) achieved CR. The actuarial 5-year survival rate of all patients was 52%. The median RDI for cyclophosphamide was 0.72, for doxorubicin 0.70, for vincristine 0.69 and the median average RDI was 0.69. The following favorable prognostic factors were found to be of statistical significance: female sex and stages I-III as compared to stage IV. The 5-year survival rate for stage III patients treated by CHOP plus radiotherapy was 70% as compared to 55% for those treated by CHOP only; this difference was not statistically significant.

The flow behavior of water-in-oil microemulsions through beds packed with glass spheres was studied experimentally. The microemulsions used in this study exhibited a shear thinning viscosity described by a simple power law model. The flow of the microemulsions was accompanied by significant apparent slip effects, quantified by an effective slip velocity. The effective slip velocity increased with increasing surfactant concentration, but it differed in magnitude for the packed bed and the capillary tube flows. In the absence of apparent slip effects, the capillary-power law (CPL) model predicted the superficial velocities in the packed beds with an average error of less than 6%. This provides a direct verification of the applicability of the capillary-power law model to inelastic shear thinning fluids in the absence of “anomalous” wall effects.

An analysis is presented to describe the parallel flow of power-law fluids within a channel bounded by porous media. It is shown that there is an excess flow above the Darcy's law prediction for the porous medium region adjacent to the channel/ porous medium boundary. This also leads to a higher flow rate in the channel. The excess flow increases with a decreasing value of the power law index, and with increasing permeability. The excess flow is found to reach a maximum at an intermediate value of the dimensionless channel width (=½H/K½and it vanishes in the limit of h→∞and h→0. Experimental evidence is also presented to demonstrate the excess flow. The experimental data are found to be in reasonable agreement with the proposed flow model.