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Spectral Analysis of Solar Variability and their Possible Role on the Global Warming

Spectral Analysis of Solar Variability and their Possible Role on the Global Warming

Our understanding of the indirect effect of changes in solar output and feedbacks in the climate system is minimal. There is much need to refine our understanding of key natural forcing mechanisms of the climate, including solar ir- radiance changes, in order to reduce uncertainty in our projections of future climate change. Through the recent years, the conflict between researchers about whether global warming is a human-generated phenomenon or a result of solar variability has raised many question marks. The aim of this work is to try to answer some of these questions by studying the possible role of some solar variability parameters such as the geomagnetic index (aa) and the sunspot number (Rz) in global temperature changes. Here, we present a correlative study of the possible contributions for the two compo- nents that may be closely associated with the climate, throughout the last 130 years (1880-2008). We compared the correlation analysis and the power spectral density (PSD) of the Rz and aa with that of the continuous records of the GT in order to get a closer look at a possible connection between them. Our results displayed that the correlations be- tween both (aa & GST) and (Rz & GST) are +0.66 and +0.38, respectively when both parameters Rz and aa precedes by 2-3 yrs. The correlation of GST-aa is two times higher than that of GST-Rz. The GST spectrum reflected significant periods at 21.3-yr, 10.7-11.6 yr variations that observed in the considered geomagnetic and sunspot spectra.
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Roles of relaxin on cardiovascular system and its possible role in cardiovascular diseases

Roles of relaxin on cardiovascular system and its possible role in cardiovascular diseases

Relaxin and Angiogenesis: While RLX does not show direct angiogeneic effects under normal conditions, in the presence of ischemia or inflammation, it increases the production of potent angiogenic molecules such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) (Unemori, 1999). Furthermore, in a rat model of myocardial infarction (MI), systemic infusion of RLX potentiates bFGF mRNA expression by both cardiomyocytes and fibroblasts in the peri-infarct region. Similarly, in a post-MI swine model, local production of RLX by RLN2 gene-transfected myoblasts grafted into the post-ischemic myocardium significantly increased microvessel density and expression of VEGF mRNA by host cardiac cells (Formigli, 2007; Perna, 2005). These findings support a possible role of RLX in augmenting perfusion of ischemic tissue through increased vasodilation and angiogenesis in some conditions.
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Reactive Centers of Curcumin and the Possible Role of Metal Complexes of Curcumin as Antioxidants

Reactive Centers of Curcumin and the Possible Role of Metal Complexes of Curcumin as Antioxidants

The free radical reaction centers of curcumin has been suggested as its two phenolic groups, enol form of the diketone moiety and extended conjugated structure. The major contributing center is still a controversy. The mechanistic aspects of curcumin antioxidant activity have been more recently investigated at length, and the recent studies [16,17,18,19,20,21] seem to suggest the importance of phenolic -OH as was earlier surmised by Barclay et al., 2000 and Venkatesan and Rao, 2000 [22,23]. A possible role for β-diketone moiety was suggested by Sugiyama et al., 1996 [24] based on their observations using dimethyltetrahydrocurcumin and further advocated by the work of Jovanovic et al., 1999 [25].
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Possible role of autoantibodies in the pathophysiology of GM2 gangliosidoses

Possible role of autoantibodies in the pathophysiology of GM2 gangliosidoses

Our results clearly demonstrate the involvement of the FcRγ gene and the possible role of an autoim- mune response in the development of SD. Although much still remains to be elucidated, our present investigation has given us novel insights and fur- thered our understanding of the pathogenesis of SD. The contribution of autoimmunity to the pathogen- esis of LSDs will be an important factor when devel- oping effective new treatments to be used in combi- nation with other therapies such as BMT (7, 33, 34), enzyme replacement therapy (35), and substrate dep- rivation (33, 36).

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Possible role of the cavernous sinus veins in cerebrospinal fluid absorption

Possible role of the cavernous sinus veins in cerebrospinal fluid absorption

There is however, at least one theoretical objection to a possible role for dural lymphatics in CSF drainage. The cellular architecture and the presence of tight junctions between arachnoid cells are believed to contribute to the blood-brain/CSF barrier [12]. Without this barrier func- tion, the extravasated fluid and solutes from the permea- ble dural capillaries would enter the dura interstitium and possibly gain access to CSF. However, for any dural CSF transport to occur, presumably CSF would have to pass through the supposed barrier provided by the arachnoid membrane to enter dural tissues. Such transport is thought to occur through specialized areas of the mem- brane where it projects into the venous sinuses (arachnoid villi and granulations). CSF transport through the arach- noid membrane at other locations has not been given much consideration although there is some evidence to support this concept. In the studies by Killer et al., India ink injected into the subarachnoid space of the optic nerve penetrated the arachnoid and entered the interstitial compartment and lymphatics in the dura of the nerve [13]. There is the suggestion that transport across the arachnoid membrane in this tissue may be in part vesicu- lar [14]. Additionally, radiolabeled albumin injected into the subdural space in rabbits was observed to enter plasma [15] and it seems likely that dural lymphatics con- tributed to this clearance.
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The possible role of cytomegalovirus infection and pro-inflammatory IL_2 cytokine in preeclampsia

The possible role of cytomegalovirus infection and pro-inflammatory IL_2 cytokine in preeclampsia

pregnancy, HLA-G is expressed on trophoblastic cells at the maternal fetal interface and may be involved in the local immune response to viral infection. The reduced HLA-G expression is a feature of the preeclamptic placenta. 28 In this regard, CMV-infected cytotrophoblast down-regulate HLA-G which may play a role in maternal immune tolerance 41 and consequently alter the critical materno- fetal immune interface leading to preeclampsia. 28 The possible role of IL-2

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Breakdown of accommodation in nerve: a possible role for persistent sodium current

Breakdown of accommodation in nerve: a possible role for persistent sodium current

Alternative explanations of breakdown of accommodation An alternative explanation for breakdown of accommoda- tion could be the gating mode of the transient sodium channel [21]. The present paper follows the convention of assuming that activation and inactivation are two inde- pendent processes (i.e. the formalism of [22]). Today, it is known that activation and inactivation are inter-depend- ent, and that most transient sodium channels will go through an open state before entering an inactivated state [21]. This difference between the Hodgkin and Huxley formalism and recent knowledge of transient sodium channel function may have a synergistic role in break- down of accommodation. Hence, a transient sodium channel with little inactivation before channel opening would not permit a critical slope and loss of breakdown of accommodation. However, this explanation remains unproven and would not change the conclusion of the present study, that persistent and late sodium channels can cause breakdown of accommodation. The interde- pendence of transient channel activation and inactivation may change the densities of persistent sodium channels needed for creating breakdown of accommodation, and thus there may be synergism between transient and per- sistent sodium channels.
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PURE SPINORS AND THEIR POSSIBLE ROLE IN PHYSICS

PURE SPINORS AND THEIR POSSIBLE ROLE IN PHYSICS

We will adopt Cartan’s conjecture and try to draw from it the natural, straightforward, consequences. To start with, the Cartan’s equations defining pure spinors will be interpreted as equations of mo- tion for fermions (or fermion multiplets) in momentum spaces whose vectors, bilinear in pure spinors, will be null and the spaces will nat- urally result lorentzian and will be equivalent to compact manifolds. The equations naturally found in this approach are most of those historically defined ad hoc (including Maxwell’s) in theoretical physics to represent the observed phenomenology of elementary particles, thus explaining also the possible geometrical origin of some of their properties, among these internal symmetry groups (including those of the standard model), as due to the 3 complex division algebras correlated with the associated Clifford algebras. Precisely U (1) de- rives from complex numbers and is at the geometrical origin of the electric and strong charges of fermions which are consequently fore- seen to steadily appear in charged-neutral doublets (of fermions or fermion doublets) as in fact they appear in nature; SU (2) derives from quaternions and is at the origin of isospin, while SU (2) L is at
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Possible Role for Cellular Karyopherins in Regulating Polyomavirus and Papillomavirus Capsid Assembly

Possible Role for Cellular Karyopherins in Regulating Polyomavirus and Papillomavirus Capsid Assembly

pherin ␤ 1 alone inhibited the association of HPV11 L1 cap- someres with DNA, the interaction between karyopherin ␤ 1 and L1 was investigated by immunoblotting of the proteins associated with DNA after EMSA. HPV11 L1 capsomeres alone or bound by karyopherin ␣ 2, ␤ 1, or ␣ 2 ␤ 1 were subse- quently incubated with plasmid DNA, and the resultant com- plexes were resolved by agarose gel electrophoresis. Consistent with the HPV11 L1 DNA binding experiment shown in Fig. 2B, the addition of karyopherin ␣ 2 alone to the L1-DNA complex resulted in a DNA supershift, whereas addition of karyopherin ␤ 1 alone or karyopherin ␣ 2 ␤ 1 completely inhib- ited L1 DNA binding (Fig. 2C, top panel). Western blot anal- ysis of proteins transferred from agarose gels shown in the top panel of Fig. 2C identified L1 and karyopherin ␣ 2 in the su- pershifted nucleoprotein complex (Fig. 2C, anti-L1 and anti- ␣ 2 panels). A protein complex comprised of L1 and karyopherin ␤ 1 or L1 and karyopherin ␣ 2 ␤ 1 was observed in the lanes where DNA was no longer bound by L1 (Fig. 2C, anti-L1, anti- ␣ 2, and anti- ␤ 1 panels). In contrast to the formation of an L1-karyopherin ␣ 2-DNA complex, these data suggest that when karyopherin ␤ 1 or ␣ 2 ␤ 1 binds L1, L1 is subsequently unable to bind DNA. While a significant amount of DNA is released from L1 with the addition of karyopherin ␤ 1 or ␣ 2 ␤ 1 to the DNA binding reaction, it is possible that some DNA remains associated with L1, accounting for the L1 migration pattern shown in Fig. 2C. Western blot analysis of HPV11 L1 incubated with or without DNA followed by agarose gel elec- trophoresis demonstrated that the migration of L1 in native agarose gels was not altered when DNA was present in the binding reaction (not shown).
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Enzymatic action of coliphage omega8 and its possible role in infection.

Enzymatic action of coliphage omega8 and its possible role in infection.

The enzyme reaction of [8 proceeds quite fast with lipopolysaccharide preparations and markedly slower with the isolated polysaccharide moiety mannan of the lipopolysaccharide which is t[r]

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The pathogenesis of coronary artery disease  A possible role for methionine metabolism

The pathogenesis of coronary artery disease A possible role for methionine metabolism

Homocysteine is formed during the metabolism of methionine and accumulations of this and of cysteine-homocysteine mixed disulfide in the plasma indicate a partial block in the methionine[r]

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Possible role of anti idiotypic antibodies in the induction of tumor immunity

Possible role of anti idiotypic antibodies in the induction of tumor immunity

This Ab-l can contain a pi where the antigen binds, a conventional idiotope to which most Ab-2 responses including potentially internal image anti-Id can be induced, and an ri that does [r]

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Systemic movement of FT mRNA and a possible role in floral induction

Systemic movement of FT mRNA and a possible role in floral induction

In Arabidopsis the FLOWERING LOCUS T (FT) gene plays a key role in the induction of flowering (Abe et al., 2005; Wigge et al., 2005). The Arabidopsis FT protein (Corbesier et al., 2007; Jaeger and Wigge, 2007; Mathieu et al., 2007) and its orthologs from rice (Tamaki et al., 2007), cucurbit (Lin et al., 2007), and tomato (Lifschitz et al., 2006), have been shown to be a component of a systemic flowering signal that moves through the phloem from the leaves to the shoot apical meristem (SAM) to induce the switch from vegetative growth to flower formation. However more recently it has been demonstrated that, in addition to FT protein, FT RNA is also able to move systemically through the plant from leaves to the SAM (Li et al., 2009, 2011) and here we review the evidence that systemic movement of FT mRNA may have a role to play in floral induction.
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Human endogenous retroviruses: Their possible role in the molecular etiology of the schizophrenia

Human endogenous retroviruses: Their possible role in the molecular etiology of the schizophrenia

Since HERVs have been present in our genome for a very long period of time, they constitute part of our mo- lecular evolution [16]. Indeed, HERVs are thought to have played an important role in the evolution of mam- malian genomes, such that their presence may be benefi- cial to the human host. In this respect, there are several examples of their participation in important and complex biological processes, such as placental development and embryogenesis [24]. On the other hand, like any other genomic element, aberrant activity of HERvs could have fatal consequences, leading to the appearance of different
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Uncoupling of cell respiration and oxidative phosphorylation: it’s possible role in obesity

Uncoupling of cell respiration and oxidative phosphorylation: it’s possible role in obesity

by genetic polymorphism. The role of UCP1 in metabolism is well established primarily as an uncoupler for non-shivering thermogenesis but the roles of UCP2 and UCP3 in metabolism have not been clearly established because to some extent research findings have been largely inconclusive(Ricquier and Bouillaud, 2000, Boss et al., 2000). Part of the problem is that UCPs genes are under polygenic control and the phenotypes are subject to controls from many genes which may be under control of other genes (Dalgaard and Pedersen, 2001). Transgenic and knock-out mouse models were used in many studies to assess the effect of genetic variations. UCP1 knockout mice showed increased sensitivity to cold and there was no uncoupling in brown adipose tissue of mice with deleted UCP1 gene compared to the wild type(Enerback et al., 1997).When over- expression of UCP1was induced in white adipose tissue the mice didn’t become lean but developed resistance against diet induced obesity (Baumruk et al., 1999). UCP2 knockout mice were found to be not obese or resistant to diet induced obesity with normal temperature(Arsenijevic et al., 2000) and similarly UCP3 knockout mice didn’t express the expected diet induced obesity(Vidal-Puig et al., 2000) suggesting that thermo genesis may not be the primary function of UCP2 and UCP3. Some studies have shown an association between UCP2 polymorphism and energy metabolism but this association does not translate into association of UCP2 with obesity (Esterbauer et al., 2001, Evans et al., 2001).
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Possible role of adenosine in the macula densa mechanism of renin release in rabbits

Possible role of adenosine in the macula densa mechanism of renin release in rabbits

To examine whether adenosine is involved in the inhibitory action of attached macula densa on basal renin release, we exposed afferent arterioles alone and afferent arterioles with attac[r]

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The possible role of local air pollution in climate change in West Africa

The possible role of local air pollution in climate change in West Africa

347 4 Conduct targeted international field campaigns in West Africa using sophisticated 348 ground-based and airborne instrumentation for atmospheric dynamics particularly 349 diurnal ev[r]

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Possible role of natural selection in the formation of tandem-repetitive noncoding DNA.

Possible role of natural selection in the formation of tandem-repetitive noncoding DNA.

Two properties of the simulated tandem-repetitive structures were explored in this paper: the tendency to longer repeat units and larger sequence heteroge- neity between repeats wi[r]

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Melatonin: its possible role in the management of viral infections-a brief review

Melatonin: its possible role in the management of viral infections-a brief review

gastrointestinal tract, retina, thymus, bone marrow, and by leukocytes. Besides playing an important role in various functions of the body, including sleep and circadian rhythm regulation, melatonin also shows immunoregulatory, free radical scavenger and antioxidant functions. Because of these latter characteristics melatonin has also been found to be effective in fighting viral infections in a variety of experimental animal and in vitro studies. These data suggest a possible therapeutic potential of melatonin in human virus-induced disorders.

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Eye movement impairments in Parkinson's disease: possible role of extradopaminergic mechanisms

Eye movement impairments in Parkinson's disease: possible role of extradopaminergic mechanisms

There is ample evidence that PD is a multisystem dis- order with involvement of several brain regions and neurotransmitter pathways other than dopamine [12]. Hence the cause of numerous clinicopathological corre- lates of PD-related deficits such as cognitive dysfunction, dementia, depression, and behavioural or emotional dys- function have to be searched outside the nigrostriatal system. Recently, these neuropsychological and psychia- tric changes in PD have received considerable attention. They are supposed to arise either as a part of the disease itself but also as a collateral result of STN-DBS [13]. If non-dopaminergic deficits cause indeed some of the eye movement alterations in PD, it might be possible to demonstrate a correlation between such non-motor symptoms and oculomotor impairment in PD.
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