Comparison of multiple-input single-output single-user ultra-wideband systems with pre-distortion

This paper presents a performance analysis of a baseband multiple-input single-output ultra-wideband system over scenarios CM1 and CM3 of the IEEE 802.15.3a channel model, incorporating four different schemes of pre-distortion: time reversal, zero-forcing pre-equaliser, constrained least squares pre-equaliser, and minimum mean square error pre-equaliser. For the third case, a simple solution based on the steepest-descent (gradient) algorithm is adopted and compared with theoretical results. The channel estimations at the transmitter are assumed to be truncated and noisy. Results show that the constrained least squares algorithm has a good trade-off between intersymbol interference reduction and signal-to-noise ratio preservation, providing a performance comparable to the minimum mean square error method but with lower computational complexity. Copyright (C) 2011 John Wiley & Sons, Ltd.

Arterial Spin Labeling Measurements of Cerebral Perfusion Territories in Experimental Ischemic Stroke

Collateral circulation, defined as the supplementary vascular network that maintains cerebral blood flow (CBF) when the main vessels fail, constitutes one important defense mechanism of the brain against ischemic stroke. In the present study, continuous arterial spin labeling (CASL) was used to quantify CBF and obtain perfusion territory maps of the major cerebral arteries in spontaneously hypertensive rats (SHRs) and their normotensive Wistar-Kyoto (WKY) controls. Results show that both WKY and SHR have complementary, yet significantly asymmetric perfusion territories. Right or left dominances were observed in territories of the anterior (ACA), middle and posterior cerebral arteries, and the thalamic artery. Magnetic resonance angiography showed that some of the asymmetries were correlated with variations of the ACA. The leptomeningeal circulation perfusing the outer layers of the cortex was observed as well. Significant and permanent changes in perfusion territories were obtained after temporary occlusion of the right middle cerebral artery in both SHR and WKY, regardless of their particular dominance. However, animals with right dominance presented a larger volume change of the left perfusion territory (23 +/- 9%) than animals with left dominance (7 +/- 5%, P<0.002). The data suggest that animals with contralesional dominance primarily safeguard local CBF values with small changes in contralesional perfusion territory, while animals with ipsilesional dominance show a reversal of dominance and a substantial increase in contralesional perfusion territory. These findings show the usefulness of CASL to probe the collateral circulation.

Medium Chain Fatty Acids Are Selective Peroxisome Proliferator Activated Receptor (PPAR) gamma Activators and Pan-PPAR Partial Agonists

Thiazolidinediones (TZDs) act through peroxisome proliferator activated receptor (PPAR) gamma to increase insulin sensitivity in type 2 diabetes (T2DM), but deleterious effects of these ligands mean that selective modulators with improved clinical profiles are needed. We obtained a crystal structure of PPAR gamma ligand binding domain (LBD) and found that the ligand binding pocket (LBP) is occupied by bacterial medium chain fatty acids (MCFAs). We verified that MCFAs (C8-C10) bind the PPAR gamma LBD in vitro and showed that they are low-potency partial agonists that display assay-specific actions relative to TZDs; they act as very weak partial agonists in transfections with PPAR gamma LBD, stronger partial agonists with full length PPAR gamma and exhibit full blockade of PPAR gamma phosphorylation by cyclin-dependent kinase 5 (cdk5), linked to reversal of adipose tissue insulin resistance. MCFAs that bind PPAR gamma also antagonize TZD-dependent adipogenesis in vitro. X-ray structure B-factor analysis and molecular dynamics (MD) simulations suggest that MCFAs weakly stabilize C-terminal activation helix (H) 12 relative to TZDs and this effect is highly dependent on chain length. By contrast, MCFAs preferentially stabilize the H2-H3/beta-sheet region and the helix (H) 11-H12 loop relative to TZDs and we propose that MCFA assay-specific actions are linked to their unique binding mode and suggest that it may be possible to identify selective PPAR gamma modulators with useful clinical profiles among natural products.

Caffeic acid phenethyl ester reduces the activation of the nuclear factor kappa B pathway by high-fat diet-induced obesity in mice

Objective. The aim of this study was to investigate the effect of CAPE on the insulin signaling and inflammatory pathway in the liver of mice with high fat diet induced obesity. Material/Methods. Swiss mice were fed with standard chow or high-fat diet for 12-week. After the eighth week, animals in the HFD group with serum glucose levels higher than 200 mg/dL were divided into two groups, HFD and HFD receiving 30 mg/kg of CAPE for 4 weeks. After 12 weeks, the blood samples could be collected and liver tissue extracted for hormonal and biochemical measurements, and insulin signaling and inflammatory pathway analyzes. Results. The high-fat diet group exhibited more weight gain, glucose intolerance, and hepatic steatosis compared with standard diet group. The CAPE treatment showed improvement in glucose sensitivity characterized by an area under glucose curve similar to the control group in an oral glucose tolerance test Furthermore, CAPE treatment promoted amelioration in hepatic steatosis compared with the high-fat diet group. The increase in glucose sensitivity was associated with the improvement in insulin-stimulated phosphorylation of the insulin receptor substrate-2, followed by an increase in Akt phosphorylation. In addition, it was observed that CAPE reduced the induction of the inflammatory pathway, c-jun-N- terminal kinase, the nuclear factor kappa B, and cyclooxygenase-2 expression, respectively. Conclusions. Overall, these findings indicate that CAPE exhibited anti-inflammatory activity that partly restores normal metabolism, reduces the molecular changes observed in obesity and insulin resistance, and therefore has a potential as a therapeutic agent in obesity. (C) 2012 Elsevier Inc. All rights reserved.

Topical Insulin Accelerates Wound Healing in Diabetes by Enhancing the AKT and ERK Pathways: A Double-Blind Placebo-Controlled Clinical Trial

Background: Wound healing is impaired in diabetes mellitus, but the mechanisms involved in this process are virtually unknown. Proteins belonging to the insulin signaling pathway respond to insulin in the skin of rats. Objective: The purpose of this study was to investigate the regulation of the insulin signaling pathway in wound healing and skin repair of normal and diabetic rats, and, in parallel, the effect of a topical insulin cream on wound healing and on the activation of this pathway. Research Design and Methods: We investigated insulin signaling by immunoblotting during wound healing of control and diabetic animals with or without topical insulin. Diabetic patients with ulcers were randomized to receive topical insulin or placebo in a prospective, double-blind and placebo-controlled, randomized clinical trial (NCT 01295177) of wound healing. Results and Conclusions: Expression of IR, IRS-1, IRS-2, SHC, ERK, and AKT are increased in the tissue of healing wounds compared to intact skin, suggesting that the insulin signaling pathway may have an important role in this process. These pathways were attenuated in the wounded skin of diabetic rats, in parallel with an increase in the time of complete wound healing. Upon topical application of insulin cream, the wound healing time of diabetic animals was normalized, followed by a reversal of defective insulin signal transduction. In addition, the treatment also increased expression of other proteins, such as eNOS (also in bone marrow), VEGF, and SDF-1 alpha in wounded skin. In diabetic patients, topical insulin cream markedly improved wound healing, representing an attractive and cost-free method for treating this devastating complication of diabetes.

Increasing Intensity of TENS Prevents Analgesic Tolerance in Rats

Transcutaneous electrical nerve stimulation (TENS) reduces hyperalgesia and pain. Both low-frequency (LF) and high-frequency (HF) TENS, delivered at the same intensity (90% motor threshold [MT]) daily, result in analgesic tolerance with repeated use by the fifth day of treatment. The current study tested 1) whether increasing intensity by 10% per day prevents the development of tolerance to repeated TENS; and 2) whether lower intensity TENS (50% MT) produces an equivalent reduction in hyperalgesia when compared to 90% MT TENS. Sprague-Dawley rats with unilateral knee joint inflammation (3% carrageenan) were separated according to the intensity of TENS used: sham, 50% LF, 50% HF, 90% LF, 90% HF, and increased intensity by 10% per day (IF and HF). The reduced mechanical withdrawal threshold following the induction of inflammation was reversed by application of TENS applied at 90% MT intensity and increasing intensity for the first 4 days. On the fifth day, the groups that received 90% MT intensity showed tolerance. Nevertheless, the group that received an increased intensity on each day still showed a reversal of the mechanical withdrawal threshold with TENS. These results show that the development of tolerance can be delayed by increasing intensity of TENS. Perspective: Our results showed that increasing intensity in both frequencies of TENS was able to prevent analgesic tolerance. Results from this study suggest that increasing intensities could be a clinical method to prevent analgesic tolerance and contribute to the effective use of TENS in reducing inflammatory pain and future clinical trials. (c) 2012 by the American Pain Society

Self-similar Expansion of the Density Profile in a Turbulent Bose-Einstein Condensate

In a recent study we demonstrated the emergence of turbulence in a trapped Bose-Einstein condensate of Rb-87 atoms. An intriguing observation in such a system is the behavior of the turbulent cloud during free expansion. The aspect ratio of the cloud size does not change in the way one would expect for an ordinary non-rotating (vortex-free) condensate. Here we show that the anomalous expansion can be understood, at least qualitatively, in terms of the presence of vorticity distributed throughout the cloud, effectively counteracting the usual reversal of the aspect ratio seen in free time-of-flight expansion of non-rotating condensates.

Absence of inactivating mutations and deletions in the DMRT1 and FGF9 genes in a large cohort of 46,XY patients with gonadal dysgenesis

Despite advances in our understanding of the mechanisms involved in sex determination and differentiation, the specific roles of many genes in these processes are not completely understood in humans. Both DMRT1 and FGF9 are among this group of genes. Dmrt1 controls germ cell differentiation, proliferation, migration and pluripotency and Sertoli cell proliferation and differentiation. Fgf9 has been considered a critical factor in early testicular development and germ cell survival in mice. We screened for the presence of DMRT1 and FGF9 mutations in 33 patients with 46,XY gonadal dysgenesis. No deletions in either DMRT1 or FGF9 were identified using the MLPA technique. Eight allelic variants of DMRT1 were identified, and in silico analysis suggested that the novel c.968-15insTTCTCTCT variant and the c.774G>C (rs146975077) variant could have potentially deleterious effects on the DMRT1 protein. Nine previously described FGF9 allelic variants and six different alleles of the 3' UTR microsatellite were identified. However, none of these DMRT1 or FGF9 variants was associated with increased 46,XY gonadal dysgenesis. In conclusion, our study suggests that neither DMRT1 nor FGF9 abnormalities are frequently involved in dysgenetic male gonad development in patients with non-syndromic 46,XY disorder of sex development. (C) 2012 Published by Elsevier Masson SAS.

Dynamic symmetry loss of high-frequency hysteresis loops in single-domain particles with uniaxial anisotropy

Understanding how magnetic materials respond to rapidly varying magnetic fields, as in dynamic hysteresis loops, constitutes a complex and physically interesting problem. But in order to accomplish a thorough investigation, one must necessarily consider the effects of thermal fluctuations. Albeit being present in all real systems, these are seldom included in numerical studies. The notable exceptions are the Ising systems, which have been extensively studied in the past, but describe only one of the many mechanisms of magnetization reversal known to occur. In this paper we employ the Stochastic Landau-Lifshitz formalism to study high-frequency hysteresis loops of single-domain particles with uniaxial anisotropy at an arbitrary temperature. We show that in certain conditions the magnetic response may become predominantly out-of-phase and the loops may undergo a dynamic symmetry loss. This is found to be a direct consequence of the competing responses due to the thermal fluctuations and the gyroscopic motion of the magnetization. We have also found the magnetic behavior to be exceedingly sensitive to temperature variations, not only within the superparamagnetic-ferromagnetic transition range usually considered, but specially at even lower temperatures, where the bulk of interesting phenomena is seen to take place. (C) 2011 Elsevier B.V. All rights reserved.

The Global Paleomonsoon as seen through speleothem records from Asia and the Americas

The regional monsoons of the world have long been viewed as seasonal atmospheric circulation reversal-analogous to a thermally-driven land-sea breeze on a continental scale. This conventional view of monsoons is now being integrated at a global scale and accordingly, a new paradigm has emerged which considers regional monsoons to be manifestations of global-scale seasonal changes in response to overturning of atmospheric circulation in the tropics and subtropics, and henceforth, interactive components of a singular Global Monsoon (GM) system. The paleoclimate community, however, tends to view 'paleomonsoon' (PM), largely in terms of regional circulation phenomena. In the past decade, many high-quality speleothem oxygen isotope (delta O-18) records have been established from the Asian Monsoon and the South American Monsoon regions that primarily reflect changes in the integrated intensities of monsoons on orbital-to-decadal timescales. With the emergence of these high-resolution and absolute-dated records from both sides of the Equator, it is now possible to test a concept of the 'Global-Paleo-Monsoon' (GPM) on a wide-range of timescales. Here we present a comprehensive synthesis of globally-distributed speleothem delta O-18 records and highlight three aspects of the GPM that are comparable to the modern GM: (1) the GPM intensity swings on different timescales; (2) their global extent; and (3) an anti-phased inter-hemispheric relationship between the Asian and South American monsoon systems on a wide range of timescales.

Cellular interference in craniofrontonasal syndrome: males mosaic for mutations in the X-linked EFNB1 gene are more severely affected than true hemizygotes

Craniofrontonasal syndrome (CFNS), an X-linked disorder caused by loss-of-function mutations of EFNB1, exhibits a paradoxical sex reversal in phenotypic severity: females characteristically have frontonasal dysplasia, craniosynostosis and additional minor malformations, but males are usually more mildly affected with hypertelorism as the only feature. X-inactivation is proposed to explain the more severe outcome in heterozygous females, as this leads to functional mosaicism for cells with differing expression of EPHRIN-B1, generating abnormal tissue boundaries-a process that cannot occur in hemizygous males. Apparently challenging this model, males occasionally present with a more severe female-like CFNS phenotype. We hypothesized that such individuals might be mosaic for EFNB1 mutations and investigated this possibility in multiple tissue samples from six sporadically presenting males. Using denaturing high performance liquid chromatography, massively parallel sequencing and multiplex-ligation-dependent probe amplification (MLPA) to increase sensitivity above standard dideoxy sequencing, we identified mosaic mutations of EFNB1 in all cases, comprising three missense changes, two gene deletions and a novel point mutation within the 5' untranslated region (UTR). Quantification by Pyrosequencing and MLPA demonstrated levels of mutant cells between 15 and 69%. The 5' UTR variant mutates the stop codon of a small upstream open reading frame that, using a dual-luciferase reporter construct, was demonstrated to exacerbate interference with translation of the wild-type protein. These results demonstrate a more severe outcome in mosaic than in constitutionally deficient males in an X-linked dominant disorder and provide further support for the cellular interference mechanism, normally related to X-inactivation in females.

Role of an indole-thiazolidine molecule PPAR pan-agonist and COX inhibitor on inflammation and microcirculatory damage in acute gastric lesions

The present study aimed to show the in vivo mechanisms of action of an indole-thiazolidine molecule peroxisome-proliferator activated receptor pan-agonist (PPAR pan) and cyclooxygenase (COX) inhibitor, LYSO-7, in an ethanol/HCl-induced (Et/HCl) gastric lesion model. Swiss male mice were treated with vehicle, LYSO-7 or Bezafibrate (p.o.) 1 hour before oral administration of Et/HCl (60%/0.03M). In another set of assays, animals were injected i.p. with an anti-granulocyte antibody, GW9962 or L-NG-nitroarginine methyl ester (L-NAME) before treatment. One hour after Et/HCl administration, neutrophils were quantified in the blood and bone marrow and the gastric microcirculatory network was studied in situ. The gastric tissue was used to quantify the percentage of damaged area, as well as myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS) protein and PPARγ protein and gene expression. Acid secretion was evaluated by the pylorus ligation model. LYSO-7 or Bezafibrate treatment reduced the necrotic area. LYSO-7 treatment enhanced PPARγ gene and protein expression in the stomach, and impaired local neutrophil influx and stasis of the microcirculatory network caused by Et/HCl administration. The effect seemed to be due to PPARγ agonist activity, as the LYSO-7 effect was abolished in GW9962 pre-treated mice. The reversal of microcirculatory stasis, but not neutrophil influx, was mediated by nitric oxide (NO), as L-NAME pre-treatment abolished the LYSO-7-mediated reestablishment of microcirculatory blood flow. This effect may depend on enhanced eNOS protein expression in injured gastric tissue. The pH and concentration of H(+) in the stomach were not modified by LYSO-7 treatment. In addition, LYSO-7 may induce less toxicity, as 28 days of oral treatment did not induce weight loss, as detected in pioglitazone treated mice. Thus, we show that LYSO-7 may be an effective treatment for gastric lesions by controlling neutrophil influx and microcirculatory blood flow mediated by NO

The juvenile three-spined stickleback : model organism for the study of estrogenic and androgenic endocrine disruption in laboratory and field

Industrial and domestic sewage effluents have been found to cause reproductive disorders in wild fish, often as a result of the interference of compounds in the effluents with the endocrine system. This thesis describes laboratory-based exposure experiments and a field survey that were conducted with juveniles of the three-spined stickleback, Gasterosteus aculeatus. This small teleost is a common fish in Swedish coastal waters and was chosen as an alternative to non-native test species commonly used in endocrine disruption studies, which allows the comparison of field data with results from laboratory experiments. The aim of this thesis was to elucidate 1) if genetic sex determination and differentiation can be disturbed by natural and synthetic steroid hormones and 2) whether this provides an endpoint for the detection of endocrine disruption, 3) to evaluate the applicability of specific estrogen- and androgen-inducible marker proteins in juvenile three-spined sticklebacks, 4) to investigate whether estrogenic and/or androgenic endocrine disrupting activity can be detected in effluents from Swedish pulp mills and domestic sewage treatment plants and 5) whether such activity can be detected in coastal waters receiving these effluents. Laboratory exposure experiments found juvenile three-spined sticklebacks to be sensitive to water-borne estrogenic and androgenic steroid substances. Intersex – the co-occurrence of ovarian and testicular tissue in gonads – was induced by 17β-estradiol (E2), 17α-ethinylestradiol (EE2), 17α-methyltestosterone (MT) and 5α-dihydrotestosterone (DHT). The first two weeks after hatching was the phase of highest sensitivity. MT was ambivalent by simultaneously eliciting masculinizing and feminizing effects. When applying a DNA-based method for genetic sex identification, it was found that application of MT only during the first two weeks after hatching caused total and apparently irreversible development of testis in genetic females. E2 caused gonad type reversal from male to female. E2 and EE2 induced vitellogenin - the estrogen-responsive yolk precursor protein, while DHT and MT induced spiggin – the androgen-responsive glue protein of the stickleback. None of the effluents from two pulp mills and two domestic sewage treatment plants had any estrogenic or androgenic activity. Juvenile three-spined sticklebacks were collected during four subsequent summers at the Swedish Baltic Sea coast in recipients of effluents from pulp mills and a domestic sewage treatment plant as well as remote reference sites. No sings of endocrine disruption were observed at any site, when studying gonad development or marker proteins, except for a deviation of sex ratios at a reference site. The three-spined stickleback – with focus on the juvenile stage – was found to be a sensitive species suitable for the study of estrogenic and androgenic endocrine disruption.

Evaluation of alkali flooding combined with intermittent flow in carbonate reservoir

The majority of carbonate reservoir is oil-wet, which is an unfavorable condition for oil production. Generally, the total oil recovery after both primary and secondary recovery in an oil-wet reservoir is low. The amount of producible oil by enhanced oil recovery techniques is still large. Alkali substances are proven to be able to reverse rock wettability from oil-wet to water-wet, which is a favorable condition for oil production. However, the wettability reversal mechanism would require a noneconomical aging period to reach the maximum reversal condition. An intermittent flow with the optimum pausing period is then combined with alkali flooding (combination technique) to increase the wettability reversal mechanism and as a consequence, oil recovery is improved. The aims of this study are to evaluate the efficiency of the combination technique and to study the parameters that affect this method. In order to implement alkali flooding, reservoir rock and fluid properties were gathered, e.g. interfacial tension of fluids, rock wettability, etc. The flooding efficiency curves are obtained from core flooding and used as a major criterion for evaluation the performance of technique. The combination technique improves oil recovery when the alkali concentration is lower than 1% wt. (where the wettability reversal mechanism is dominant). The soap plug (that appears when high alkali concentration is used) is absent in this combination as seen from no drop of production rate. Moreover, the use of low alkali concentration limits alkali loss. This combination probably improves oil recovery also in the fractured carbonate reservoirs in which oil is uneconomically produced. The results from the current study indicate that the combination technique is an option that can improve the production of carbonate reservoirs. And a less quantity of alkali is consumed in the process.

Il concetto di sezione nel metodo compositivo di Aldo Rossi.

Purpose of this research is to deepen the study on the section in architecture. The survey aims as important elements in the project Teatro Domestico by Aldo Rossi built for the XVII Triennale di Milano in 1986 and, through the implementation on several topics of architecture, verify the timeliness and fertility in the new compositional exercises. Through the study of certain areas of the Rossi’s theory we tried to find a common thread for the reading of the theater project. The theater is the place of the ephemeral and the artificial, which is why his destiny is the end and the fatal loss. The design and construction of theater setting has always had a double meaning between the value of civil architecture and testing of new technologies available. Rossi's experience in this area are clear examples of the inseparable relationship between the representation of architecture as art and design of architecture as a model of reality. In the Teatro Domestico, the distinction between representation and the real world is constantly canceled and returned through the reversal of the meaning and through the skip of scale. At present, studies conducted on the work of Rossi concern the report that the architectural composition is the theory of form, focusing compositional development of a manufacturing process between the typological analysis and form invention. The research, through the analysis of some projects few designs, will try to analyze this issue through the rules of composition both graphical and concrete construction, hoping to decipher the mechanism underlying the invention. The almost total lack of published material on the project Teatro Domestico and the opportunity to visit the archives that preserve the drawings, has allowed the author of this study to deepen the internal issues in the project, thus placing this search as a first step toward possible further analysis on the works of Rossi linked to performance world. The final aim is therefore to produce material that can best describe the work of Rossi. Through the reading of the material published by the same author and the vision of unpublished material preserved in the archives, it was possible to develop new material and increasing knowledge about the work, otherwise difficult to analyze. The research is divided into two groups. The first, taking into account the close relationship most frequently mentioned by Rossi himself between archeology and architectural composition, stresses the importance of tipo such as urban composition reading system as well as open tool of invention. Resuming Ezio Bonfanti’s essay on the work of the architect we wanted to investigate how the paratactic method is applied to the early work conceived and, subsequently as the process reaches a complexity accentuated, while keeping stable the basic terms. Following a brief introduction related to the concept of the section and the different interpretations that over time the term had, we tried to identify with this facility a methodology for reading Rossi’s projects. The result is a constant typological interpretation of the term, not only related to the composition in plant but also through the elevation plans. The section is therefore intended as the overturning of such elevation is marked on the same plane of the terms used, there is a different approach, but a similarity of characters. The identification of architectural phonemes allows comparison with other arts. The research goes in the direction of language trying to identify the relationship between representation and construction, between the ephemeral and the real world. In this sense it will highlight the similarities between the graphic material produced by Ross and some important examples of contemporary author. The comparison between the composition system with the surrealist world of painting and literature will facilitate the understanding and identification of possible rules applied by Rossi. The second part of the research is characterized by a focus on the intent of the project chosen. Teatro Domestico embodies a number of elements that seem to conclude (assuming an end point but also to start) a curriculum author. With it, the experiments carried out on the theater started with the project for the Teatrino Scientifico (1978) through the project for the Teatro del Mondo (1979), into a Laic Tabernacle representative collective and private memory of the city. Starting from a reading of the draft, through the collection of published material, we’ve made an analysis on the explicit themes of the work, finding the conceptual references. Following the taking view of the original materials not published kept at Aldo Rossi's Archive Collection of the Canadian Center for Architecture in Montréal, will be implemented through the existing techniques for digital representation, a virtual reconstruction of the project, adding little to the material, a new element for future studies. The reconstruction is part of a larger research studies where the current technologies of composition and representation in architecture stand side by side with research on the method of composition of this architect. The results achieved are in addition to experiences in the past dealt with the reconstruction of some of the lost works of Aldo Rossi. A partial objective is to reactivate a discourse around this work is considered non-principal, among others born in the prolific activities. Reassessment of development projects which would bring the level of ephemeral works most frequented by giving them the value earned. In conclusion, the research aims to open a new field of interest on the part not only as a technical instrument of representation of an idea but as an actual mechanism through which composition is formed and the idea is developed.