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The thermal performance of a novel hybrid nanofluid containing graphene oxide (GO)–gold/water and GO/water nanofluid in cooling a computer's CPU is carried out experimentally. Single-layer graphene oxide is used as working fluid by combining specific amounts of gold nanoparticle suspension with varying concentrations (0.0044–0.0114 mass%) and Reynolds number (676–2185) to optimize the overall device performance. The obtained results revealed that GO/water nanofluid and GO–gold/water hybrid nanofluid reduced the surface temperature of the CPU by 10.6% and 16.2%, respectively, compared with the DI water. Also, the results show that the convective heat transfer coefficient is improved by 36.36% with GO–gold/water hybrid nanofluid (0.0094 mass%) and Re = 2185. In addition, new correlations have been developed for predicting the Nusselt number of GO–gold/water hybrid nanofluid and GO/water nanofluid, based on the experimental data. Overall, the hybrid nanofluid is highly recommended as a preferred cooling in electronic devices. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is a pathogenic protozoan parasite belonging to the apicomplexan phylum that infects the nucleated cells of warm-blooded hosts leading to an infectious disease known as toxoplasmosis. Apicomplexan parasites such as T. gondii can display different mechanisms to control or manipulate host cells signaling at different levels altering the host subcellular genome and proteome. Indeed, Toxoplasma is able to modulate host cell responses (especially immune responses) during infection to its advantage through both structural and functional changes in the proteome of different infected cells. Consequently, parasites can transform the invaded cells into a suitable environment for its own replication and the induction of infection. Proteomics as an applicable tool can identify such critical proteins involved in pathogen (Toxoplasma)-host cell interactions and consequently clarify the cellular mechanisms that facilitate the entry of pathogens into host cells, and their replication and transmission, as well as the central mechanisms of host defense against pathogens. Accordingly, the current paper reviews several proteins (identified using proteomic approaches) differentially expressed in the proteome of Toxoplasma-infected host cells (macrophages and human foreskin fibroblasts) and tissues (brain and liver) and highlights their plausible functions in the cellular biology of the infected cells. The identification of such modulated proteins and their related cell impact (cell responses/signaling) can provide further information regarding parasite pathogenesis and biology that might lead to a better understanding of therapeutic strategies and novel drug targets. [ABSTRACT FROM AUTHOR]

Objective: Systemic lupus erythematosus (SLE), the most common form of lupus, is a multisystemic rheumatic disease with different clinical features that generally affect women of childbearing age. The common symptoms of SLE are very similar to other autoimmune and non-autoimmune disorders, thereby it is known as a thousand faces disease. In this article, we are going to discuss some of the most updated information about immune system-related factors, cells, and cytokines involved in SLE pathogenesis. Methods: Different electronic databases, especially PubMed/MEDLINE, Scopus, and Google Scholar, were searched to review and analyze relevant literature on the role of innate and adaptive immune cells and cytokines in the pathogenesis of SLE. A search for relevant literature was accomplished using various keywords including systemic lupus erythematosus, apoptosis, autoantibodies, immunopathogenesis of SLE, adaptive and innate immune cells, inflammatory cytokines, hormones, etc. Results and conclusion: The most important characteristic of SLE is the production of antibodies against different nuclear autoantigens like double-strand DNA and RNA. The depositions of the immune complexes (ICs) that are generated between autoantibodies and autoantigens, along with aberrant clearance of them, can lead to permanent inflammation and contribute to tissue or organ damage. Related mechanisms underlying the initiation and development of SLE have not been clarified yet. Although, defects in immune tolerance, enhanced antigenic load, hyperactivity of T cells, and inappropriate regulation of B cells contribute to the pathogenic autoantibodies generation. Besides, sex hormones that influence the immune system seem to act as triggers or protectors of SLE development. [ABSTRACT FROM AUTHOR]

The current drug treatments against protozoan parasitic diseases including Chagas, malaria, leishmaniasis, and toxoplasmosis represent good examples of drug resistance mechanisms and have shown diverse side effects. Therefore, the identification of novel therapeutic strategies and drug compounds against such life-threatening diseases is urgent. According to the successful usage of selenium (Se) compounds-based therapy against some diseases, this therapeutic strategy has been recently further underlined against these parasitic diseases by targeting different parasite´s essential pathways. On the other hand, due to the important functions played by parasite selenoproteins in their biology (such as modulating the host immune response), they can be also considered as a novel therapeutic strategy by designing specific inhibitors against these important proteins. In addition, the immunomodulatory potentiality of these compounds to trigger T helper type 1 (Th1) cells and cytokine-mediated immune response for the substantial induction of proinflammatory cytokines, thus, Se, selenoproteins, and parasite selenoproteins could be further investigated to find possible vaccine antigens. Herein, we collect and present the results of some studies regarding Se-based therapy against protozoan parasitic diseases and highlight relevant information and some viewpoints that might be insightful to advance toward more effective studies in the future. [ABSTRACT FROM AUTHOR]

From the seismologists' point of view, it is extremely important to accurately detect the first P wave arrival time. The P wave arrivals have considerable information about events such as location, magnitude, mechanism, and source parameters. In the classic methods, P wave pickings have been accomplished manually in a visual way. But in the era of information and communication technology, it can be done by computer programs. Seismologists have developed many methods for the picking of the first arrival time of P wave. The wavelet transform is one of the methods to analyze the arrival times and useful for picking up the singularities of any function. Decomposing signals by wavelet transform is a master key to the study of time-frequency varying signals such as earthquake seismograms. This paper presents P phase picking without any prior information using undecimated wavelet transform. For undertaking this study, a simple envelope characteristic function is used for P phase picking. The proposed method is tested on 5 earthquakes recorded by the Fnet network in Japan that have varying signal-to-noise ratio levels for calibrating. Then the method is applied on 50 earthquakes. The observed results are compared with manual phase picking and standard STA/LTA method. The wavelet base method shows the higher accuracy of phase picking in event detection and time picking, respect to the standard STA/LTA method, when compared to manual picking. [ABSTRACT FROM AUTHOR]

Ankylosing spondylitis (AS) is a debilitating chronic inflammatory disease with genetic predisposition, which is characterized by the involvement of spine and sacroiliac joints. Due to the relatively unsuccessful treatments, we designed β-d-mannuronic (M2000) with the beneficial effects in various experimental models as a novel non-steroidal anti-inflammatory drug (NSAID). The aims of our present study were: first, to compare the therapeutic effects of M2000, as a novel designed NSAID, with naproxen and placebo in Iranian patients with AS during 12 weeks; second, to evaluate the effect of M2000 on gene expression of cyclooxygenase enzyme (COX-1/COX-2), a key enzyme in the initiation of inflammatory pathways in AS patients; and third, to assess the activity of COX-1 and COX-2 enzymes in the presence/absence of M2000 at the different doses in the murine macrophage, J774 cell line. This was a sub-study of phase II, randomized, placebo-controlled trial with three treatment arms: M2000, naproxen, and placebo. The outcome measures were the mean changes from baseline to week 12. The gene expression was assessed by real-time PCR. The COX-1 and COX-2 activities were evaluated by ELISA in J774 cell line induced by LPS and arachidonic acid (AA). Our findings demonstrated that M2000 had beneficial therapeutic effects on pain, stiffness, and inflammation, whereas no adverse effects were observed following the use of M2000 after 12 weeks. The analysis of gene expression showed that M2000 could effectively reduce the expression levels of COX-1 and COX-2 in comparison with untreated patients. In addition, the enzymatic activities in the presence of M2000 were significantly less than LPS- and AA-treated groups. Our results indicate that M2000, as a novel designed NSAID with immunosuppressive properties, can be considered as one of the therapeutic options for the treatment of inflammatory diseases without adverse events.Clinical trial identifier IRCT2013062213739N1/http://www.IRCT.ir. [ABSTRACT FROM AUTHOR]

We present a field survey and a number of simulations of the local Persian Gulf tsunami of 19 March 2017 at Bandar Dayyer, Iran, which resulted in one death, five persons missing and significant damage to the port. The field survey defined the inundated area as extending $$\sim\, 40$$ km along the coast, with major effects concentrated on an $$\sim\, 8$$ km stretch immediately west of Dayyer, a maximum run-up of 3 m and maximum inundation reaching 600 m. In the absence of significant earthquakes on that day, we first test the possibility of generation of a landslide; however, our simulations for legitimate sources fail to reproduce the distribution of run-up along the coast. We prefer the model of a meteorological tsunami, triggered by Proudman resonance with a hypothetical weather front moving at 10 m/s in a NNW azimuth, which could be an ancillary phenomenon to a major shamal wind system present over the Persian Gulf on that day. More detailed simulations of the Dayyer tsunami would require an improved bathymetric grid in the vicinity of the relevant coastal segment. [ABSTRACT FROM AUTHOR]

Purpose: Our purpose was to analyse the presentation, management and clinical outcome of patients treated operatively and non-operatively for Copenhagen Disease (CD).Methods: We performed a retrospective analysis of 10 patients (n = 10) with CD, with a mean follow-up time of 14.7 years. Seven patients underwent non-operative treatment and three patients were treated operatively. Clinical presentation and radiological findings were analysed. Health-related quality of life (HRQOL) outcome measures utilized included Oswestry Disability Index (ODI), Short Form 12 Health Survey (SF-12) and visual analogue scale (VAS).Results: Patients tended to present with back pain. No significant difference was detected in functional scores at time of diagnosis and when compared to last follow-up. ODI improved from 20.0 to 18.4 (p = 0.839), PCS component of SF-12 from 44.5 to 45.9 (p = 0.719), MCS component of SF-12 from 45.7 to 46.9 (p = 0.840) and VAS score remained at 2.8 (p = 1.000). There was no significant difference in functional scores when comparing operative and non-operative treatment groups.Conclusion: CD is likely to remain stable with time or slightly improve after treatment according to functional outcomes tests. Progression of the kyphosis can be halted at different degrees with operative and non-operative treatments although it does not correlate with changes in symptomatology. [ABSTRACT FROM AUTHOR]

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease with complex genetic inheritance that affecting different organs and systems. STAT4 has been newly identified as a susceptible gene in the development of SLE. According to recent studies, STAT4 has been associated with SLE in various populations. We investigated whether STAT4 single nucleotide polymorphisms (SNPs) were associated with susceptibility and clinical features of SLE in Iranian patients. The study group comprised 280 patients with SLE and 281 sex-, age-, and ethnicity-matched healthy controls of Iranian ancestry. Two SNPs (rs7574865 and rs7601754) were genotyped using the TaqMan MGB Allelic Discrimination method. Our results showed a significant association betweenrs7574865 T allele (odds ratio (OR) = 1.50, 95 % CI = 1.18-1.92, P = 0.002) and susceptibility to SLE. The rs7574865TT genotype ( P = 0.02, OR = 1.94, 95 % CI = 1.74-3.19) and GT genotype ( P = 0.008, OR = 1.71, 95 % CI = 1.19-2.45) showed a significant association with the risk of SLE in the Iranian population. We concluded that STAT4 rs7574865 is associated with SLE susceptibility in the Iranian population and this SNP might be a factor in the pathogenesis of SLE. However, further studies are required to investigate the mechanism by which polymorphisms in this gene lead to SLE. [ABSTRACT FROM AUTHOR]

Using a cosmological black hole model proposed recently, we have calculated the quasi-local mass of a collapsing structure within a cosmological setting due to different definitions put forward in the last decades to see how similar or different they are. It has been shown that the mass within the horizon follows the familiar Brown-York behavior. It increases, however, outside the horizon again after a short decrease, in contrast to the Schwarzschild case. Further away, near the void, outside the collapsed region, and where the density reaches the background minimum, all the mass definitions roughly coincide. They differ, however, substantially far from it. Generically, we are faced with three different Brown-York mass maxima: near the horizon, around the void between the overdensity region and the background, and another at cosmological distances corresponding to the cosmological horizon. While the latter two maxima are always present, the horizon mass maxima is absent before the onset of the central singularity. [ABSTRACT FROM AUTHOR]

Special solutions of the LTB family representing collapsing over-dense regions corresponding to asymptotically closed, open, or flat FRW models are found. These solutions may be considered as representing dynamical mass condensations leading to black holes immersed in a FRW universe. We study the dynamics of the collapsing region, and its density profile. The question of the strength of the central singularity and its nakedness, as well as the existence of an apparent horizon and an event horizon is dealt with in detail, shedding light to the notion of cosmological black holes. Differences to the Schwarzschild black hole are addressed. [ABSTRACT FROM AUTHOR]

This paper shows how the structure and dynamics of a lightlike thin shell in general relativity can be obtained from a distributional approach. [ABSTRACT FROM AUTHOR]

Colombeau's generalized functions are used to adapt the distributional approach to singular hypersurfaces in general relativity with signature change. Equations governing the dynamics of a singular hypersurface are derived and a specific non-vanishing form for the energy-momentum tensor of the singular hypersurface is obtained. It is shown that matching in the case of de Sitter space in the Lorentzian sector is possible along the boundary with minimum radius but leads to the vanishing of the energy-momentum tensor of the singular hypersurface. [ABSTRACT FROM AUTHOR]

The perturbation theory plays an important role in studying structure formation in cosmology and post-Newtonian physics, but not all phenomena can be described by the linear perturbation theory. Thus, it is necessary to study exact solutions or higher-order perturbations. Specifically, we study black hole (apparent) horizons and the cosmological event horizon formation in the perturbation theory. We emphasize that in the perturbative regime of the gravitational potential these horizons cannot form in the lower order. Studying the infinite plane metric, we show that, to capture the cosmological constant effect, we need at least a second-order expansion. [ABSTRACT FROM AUTHOR]

In this article the author discusses the prevalence of alleged plagiarism among scientists in Iran. He notes the availability of Internet journals and communications as a culprit for the plagiarism acts in the region. Furthermore, he mentions the share of academic fraud by the Iranian political class in the country.