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Calculating pipe diameters through long, straight pipes is executed in classic fluid flow problems using traditional trial-and-error methods or by complex equations. Most fluid mechanics textbooks facilitate the solution assuming [...]

ABSTRACTThe secondary suspension of railway vehicles is fundamental for their dynamic behaviour. This paper outlines a model-based procedure for predicting and evaluating the influence of different parameters in the static stiffness and vibration transmission of an air spring employed in the secondary suspension system of a railway vehicle. For that aim, a detailed and experimentally validated finite element model of the air spring is defined. It includes the behaviour of the reinforced elastomer, the inner pressure-deformation coupling and the thermodynamic interactions taking place inside the bellow. A Computer Aided Design of Experiments is employed to evaluate the influence of seven construction parameters of the bellow. Experimental tests and simulation results show that the air spring has natural frequencies below 100 Hz, in the frequency range where structure-borne vibration transmission occurs. The cord angle modifies the axial-transversal stiffness relation and a larger separation between adjacent layers and fibres delay the vibration transmissibility.

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Electromagnetic interference (EMI) instrumentation has significantly evolved over the last thirty years. In this paper, the classical architecture of a conventional receiver is described and compared with the newest architecture of a Fast-Fourier-transform (FFT) based receiver. Additionally, different ways to measure the modal emissions, that is, the common and differential modes, with both types of receivers are described. In a conventional receiver, modal emissions can be measured using an external noise separator. In a dual-port FFT-based receiver, this can be done in the digital domain. Both receivers have been used to measure a device under test emitting non-stationary interference.

Clinical practice guidelines for dietary intake in hemodialysis focus on individual nutrients. Little is known about associations of dietary patterns with survival. We evaluated the associations of dietary patterns with cardiovascular and all-cause mortality among adults treated by hemodialysis.

In this paper, the power quality of interconnected microgrids is managed using a Model Predictive Control (MPC) methodology which manipulates the power converters of the microgrids in order to achieve the requirements. The control algorithm is developed for the microgrids working modes: grid-connected, islanded and interconnected. The results and simulations are also applied to the transition between the different working modes. In order to show the potential of the control algorithm a comparison study is carried out with classical Proportional-Integral Pulse Width Modulation (PI-PWM) based controllers. The proposed control algorithm not only improves the transient response in comparison with classical methods but also shows an optimal behavior in all the working modes, minimizing the harmonics content in current and voltage even with the presence of non-balanced and non-harmonic-free three-phase voltage and current systems.

Bariatric surgery is currently the most effective therapy for type 2 diabetes. However, the mechanisms underlying its beneficial effects remain elusive. Here we studied the effects of bariatric surgery on circulating meteorin-like (Metrnl) and oncostatin m (OSM) levels, two hormones intimately linked to energy homeostasis. Metrnl and OSM levels were assessed at baseline, 6 and 12 months after laparoscopic sleeve gastrectomy (LSG) in 25 patients with obesity, as well as in 33 normal-weight controls. At baseline, patients with obesity showed lower Metrnl and higher OSM levels compared to controls. LSG increased Metrnl and decreased OSM levels, in correlation to improvements in glucose and lipid homeostasis. Our data indicate that LSG conversely modulated Metrnl and OSM levels, and suggest that a dual approach modulating these two molecules might provide a novel strategy for obesity and type 2 diabetes treatment.

La enfermedad crítica en el paciente pediátrico incluye desde una patología aguda en un niño sano a una agudización de una enfermedad crónica, hecho que ha conllevado centrar su atención clínica en las Unidades de Cuidados Intensivos Pediátricos. El rol del/la enfermero/a pediátrico/a se centra también en promover el confort en estos pacientes críticos. Por este motivo, es necesario disponer de instrumentos de medida que permitan un correcto sensado del grado de confort.

•Risk moderates the antecedents of online customer retention.•Satisfaction and web reputation are drivers of trust and repurchase intention.•When perceived risk is higher, the impact of trust on satisfaction is more intense.

Although tyrosine kinase inhibitors (TKIs) efficiently cure chronic myeloid leukemia (CML), they can fail to eradicate CML stem cells (CML-SCs). The mechanisms responsible for CML-SC survival need to be understood for designing therapies. Several previous studies suggest that TKIs could modulate CML-SC quiescence. Unfortunately, CML-SCs are insufficiently available. Induced pluripotent stem cells (iPSCs) offer a promising alternative. In this work, we used iPSCs derived from CML patients (Ph+). Ph+ iPSC clones expressed lower levels of stemness markers than normal iPSCs. BCR–ABL1 was found to be involved in stemness regulation and ERK1/2 to have a key role in the signaling pathway. TKIs unexpectedly promoted stemness marker expression in Ph+ iPSC clones. Imatinib also retained quiescence and induced stemness gene expression in CML-SCs. Our results suggest that TKIs might have a role in residual disease and confirm the need for a targeted therapy different from TKIs that could overcome the stemness-promoting effect caused by TKIs. Interestingly, a similar pro-stemness effect was observed in normal iPSCs and hematopoietic SCs. These findings could help to explain CML resistance mechanisms and the teratogenic side-effects of TKIs in embryonic cells.

The report of a new autochthonous case of human American Visceral Leishmaniasis (AVL) in 1992 in the village of Guayabita, Aragua State, Venezuela (10° 16'N, 67°28'W; 500 m asl), led us to undertake an epidemiological study in this locality. A demographic survey was conducted using a structured questionnaire in which data was collected regarding sex, age, occupation, length of residence in the area and migratory history. A leishmanin skin test (LST) was applied and samples of venous blood for counter immunoelectrophoresis (CIEP) and immunofluorescent antibodies (IFAT) tests were drawn. The prevalence of positive LST was 11.4 %. The positivity was highest among males and increased with age. Young males seemed to be more exposed to infection than females. Since occupation per sedid not seem to account for this association, it may be explained as a gender-associated behavior, leading to different degrees of exposure to sand flies. The canine population was also screened for leishmanial infection. One dog was shown to be parasitologically infected with Leishmaniasp. Four out of 71 dogs (5.6 %) were positive for FG, CIEP, IFAT and Western Blot and 11 (15.5 %) were positive for CIEP. These results suggest that after almost 30 years of epidemiological silence, American visceral leishmaniasis has re-emerged in this focus.

The possibility of producing anticorrosion and wear resistant cladding from stainless steel onto tool and carbon steels by means of melting in high energy density light flux is demonstrated. Experiments are conducted in an installation with two arc xenon lamps of 10 kW power of each. Metallographic investigation of the interface shows the existence of high quality metallic bond between the clad and base material. The dilution of Ni and Cr is shown to depend on the melting time. A strong correlation between microstructure of produced cladding and treatment parameters - flux density and exposure time - is revealed.

PurposeTo identify risk factors present at admission in adult patients hospitalised due to influenza virus infection during the 2009/10 and 2010/11 seasons—including whether infection was from pandemic or seasonal influenza A infections—that were associated with the likelihood of developing severe pneumonia with multilobar involvement and shock.MethodsProspective cohort study. Patients hospitalised due to influenza virus infection were recruited. We collected information on sociodemographic characteristics, pre-existing medical conditions, vaccinations, toxic habits, previous medications, exposure to social environments, and EuroQoL-5D (EQ-5D). Severe pneumonia with multilobar involvement and/or shock (SPAS) was the primary outcome of interest. We constructed two multivariate logistic regression models to explain the likelihood of developing SPAS and to create a clinical prediction rule for developing SPAS that includes clinically relevant variables.ResultsLaboratory-confirmed A(H1N1)pdm09, EQ-5D utility score 7 days before admission, more than one comorbidity, altered mental status, dyspnoea on arrival, days from onset of symptoms, and influenza season were associated with SPAS. In addition, not being vaccinated against seasonal influenza in the previous year, anaemia, altered mental status, fever and dyspnoea on arrival at hospital, difficulties in performing activities of daily living in the previous 7 days, and days from onset of symptoms to arrival at hospital were related to the likelihood of SPAS (area under the curve value of 0.75; Hosmer–Lemeshow p value of 0.84).ConclusionsThese variables should be taken into account by physicians evaluating a patient affected by influenza as additional information to that provided by the usual risk scores.

As a strategy to avoid the loss of the Zapoteca language, the Mexican government has separated elementary schooling into Spanish education and bilingual education (or indigenous education). However, this differentiation has only complicated the problem as the conditions between urban and indigenous students are not the same. Thus, our research aims to contribute to the creation of didactic material supported by interactive multimedia objects for improving literacy education in the early stages. This research combines four methodological techniques to establish a better process of teaching this ancestral language: ethnographic study, semiotic analysis, instructional design and user-centered design. We have identified a list of common problems in writing and reading the Zapoteca language, to understand the children's way of thinking and the language used by them, and we have recovered images from children's visual memory (which is associated to different concepts). Finally, the proposed educational contents should evaluate, respect, reuse and study community experiences to avoid the degradation of indigenous language and culture.

We describe an experiment in which cold rubidium atoms, confined in an elongated magnetic trap, are excited by transverse oscillation of the trap center. The temperature after excitation exhibits resonance as a function of the driving frequency. We measure these resonances at several different trap frequencies. In order to interpret the experiments, we develop a simple model that incorporates both collisions between atoms and the anharmonicity of the real three-dimensional trapping potential. As well as providing a precise connection between the transverse harmonic oscillation frequency and the temperature resonance frequency, this model gives insight into the heating and loss mechanisms and into the dynamics of driven clouds of cold trapped atoms. [ABSTRACT FROM AUTHOR]

Introducción y objetivos: evaluar el efecto de la prostatectomía radical y la edad en los resultados urodinámicos antes y después de la radioterapia de intensidad modulada administrada a pacientes con cáncer de próstata.

We study electroweak Sudakov effects in single W, Z and y production at large transverse momentum using soft collinear effective theory. We present a factorized form of the cross section near the partonic threshold with both QCD and electroweak effects included and compute the electroweak corrections arising at different scales. We analyze their size relative to the QCD corrections as well as the impact of strong-electroweak mixing terms. Numerical results for the vector-boson cross sections at the Large Hadron Collider are presented. [ABSTRACT FROM AUTHOR]

This work deals with multi-level switching amplifiers, in the context of high-efficiency power amplification for signal tracking applications. In particular, this paper evaluates the reduction in the error signal's power due to multi-level power amplification (compared to conventional two-level amplifiers) and compares the performance of two multi-level pulse modulations: PWM and Asynchronous \Sigma \Delta Modulation. First the intrinsic bandwidth limits of multi-level switching amplifiers are inferred, to clearly state the advantages and limitations of multi-level power amplification. From the existing analyses of Pulse Width Modulation already reported in the literature, PWM is herein extended to multiple levels based on an equivalent representation, which allows to derive a closed expression for the power spectrum of multi-level PWM in bandlimited signal tracking. The Asynchronous \Sigma \Delta Modulation is extended to multiple levels and the resulting multi-level encoding algorithm is analyzed in both time and frequency domains. The performance of both modulations is characterized and compared at different operating frequencies and using different number of levels. The main outcomes of this in-depth characterization show that, if the switching frequency is high enough, the tracking error is independent of the modulation and the switching frequency, i.e., it only depends upon the number of levels, which points out the suitability of asynchronous modulations for relatively low switching frequencies (compared to the number of levels). [ABSTRACT FROM PUBLISHER]

Abstract: Comparing perturbative calculations with a lattice computation of the static energy in quantum chromodynamics at short distances, we obtain a determination of the strong coupling . Our determination is performed at a scale of around 1.5 GeV (the typical distance scale of the lattice data) and, when evolved to the Z-boson mass scale , it corresponds to . [Copyright &y& Elsevier]

Alzheimers disease (AD) is characterized by several pathologies, this disease is a neuropathological lesion in brain. Indeed, a wealth of evidence suggests that -amyloid is central to the pathophysiology of AD and is likely to play an early role in this intractable neurodegenerative disorder. AD is the most prevalent form of dementia, and current indications show that twenty-nine million people live with AD worldwide, a figure expected rise exponentially over the coming decades. Clearly, blocking disease progression or, in the best-case scenario, preventing AD altogether would be of benefit in both social and economic terms. However, current AD therapies are merely palliative and only temporarily slow cognitive decline, and treatments that address the underlying pathologic mechanisms of AD are completely lacking. While familial AD (FAD) is caused by autosomal dominant mutations in either amyloid precursor protein (APP) or the presenilin (PS1, PS2) genes. First, we revised 2D QSAR, 3D QSAR, CoMFA, CoMSIA and Docking of and -secretase inhibitors. Next, we review 2D QSAR, 3D QSAR, CoMFA, CoMSIA and docking for GSK-3 and GSK-3 with different compound to find out the structural requirements.

This paper explores the modulation bandwidth limits for switching amplifiers, by analyzing the fundamental tracking capabilities of two-level switching signals. With this aim, this work synthesizes two-level switching signals by obtaining the distribution of switching events providing both minimum average switching frequency and inband-error-free encoding, targeting to minimize the amplifier switching losses when tracking a generic bandlimited signal. This analysis also provides a framework reference to characterize the deviation from such limit in modulations used in actual amplifiers. [ABSTRACT FROM PUBLISHER]

Sclerocarya birreais a medicinal plant used for the treatment of inflammatory- and bacterial-related diseases. The present study investigated in vitroand in vivothe effects of the stem bark methanol extract of S. birrea. Nitrite, TNF, IL-1β, IL-6 and IL-12p40 production by bone marrow-derived macrophages (BMDM) pre-incubated with or without S. birrea, and stimulated with Lipopolysaccharide (LPS) or infected with live Mycobacterium bovisBacillus Calmette Guérin (BCG) was evaluated. S. birreaextract inhibited, in a concentration-dependent manner, nitrite, TNF, IL-1β, IL-6 and IL-12p40 production by BMDM stimulated with LPS or infected with live BCG. The iNOS expression was reduced by S. birreaafter stimulation of BMDM with LPS. In addition, S. birreainhibited the nuclear factor κB (NF-κB) activation by both LPS and BCG. The effects of the plant extract were also evaluated in an in vivomodel of liver injury induced by D-galactosamine/LPS (D-GalN/LPS) administration in mice. S. birrealimited D-GalN/LPS-liver injury as assessed by a reduction in transaminases and TNF, IL-1β, IL-6 serum levels, and translocation of NF-κB to the nucleus. Taken together, our data indicate that stem bark methanol extract of S. birreapossesses anti-inflammatory properties by inhibiting NF-κB activation and cytokine release induced by inflammatory or infectious stimuli.

The structural polymorphism exhibited by a thin polymer film of symmetric poly(2-vinyl pyridine- b-methyl methacrylate) (P2VP- b-PMMA), cast by spin-coating, in the presence of selective solvent CCl 4has been investigated. Morphological features can be switched upon exposure to selective vapor. On the basis of this method, typical self-assembled nanostructures of block copolymers such as hexagonal, lamellar, and micellar are reported. Iron oxide magnetic nanoparticles have been modified with poly(methyl methacrylate) (PMMA) brushes by atomic transfer radical polymerization (ATRP) in order to improve dispersion and the affinity of nanoparticles to poly(methyl methacrylate) block of poly(2-vinyl pyridine- b-methyl methacrylate) block copolymer. This way of preparation of nanocomposites opens new ways on strategy to the generation of magnetic nanomaterials. Tapping-mode atomic force microscopy (TM-AFM) and magnetic force microscopy (MFM) have been employed to characterize ordered nanostructures of P2VP- b-PMMA thin films. The magnetic field generated by interactions between iron oxide nanoparticles in P2VP- b-PMMA block copolymer matrix with the magnetized tip of the MFM provokes the disappearance of hexagonal morphology.

To establish polychlorinated biphenyl (PCB) levels and distribution as well as their relationship to biometric parameters in the razor clam Ensis siliqua (Linnaeus, 1758), 15 individual samples collected from two points sited in the Islas Cies, Ria de Vigo in Galicia, Spain, collected monthly between February 2003 and April 2004, were analysed. PCBs (IUPAC No. 31, 28, 52, 101, 118, 153, 105, 138, 156 and 180) were isolated by Soxhlet extraction. Identification and quantification were performed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography (electron capture detector), respectively. The isomer concentrations in E. siliqua were in the order hexachlorobiphenyls > pentachlorobiphenyls > heptachlorobiphenyls > trichlorobiphenyls > tetrachlorbiphenyls. No correlation was observed between the E. siliqua shell length and PCBs levels. The PCBs 31, 101, 105 and 153 levels were statistically related with some biometric parameters (p < 0.05). Multivariate techniques such as principal component analysis (PCA) show clear seasonal differences between samples.

Photoswitchable enantiopure sulfinyl azo compounds have been synthesized. A remarkable perturbation of the azo system by the stereogenic sulfinyl moiety has been observed by CD in both the trans and the cis azobenzenes resulting by photoisomerization. After five irradiation cycles, the configurational integrity of these chiral switches remains unchanged.

Because of the current shortage of cadaveric organs, it is important to determine preoperatively those variables that are readily available, inexpensive, and noninvasive that can predict a higher incidence of hepatic artery thrombosis (HAT).

Sol-gel hybrid organic-inorganic and inorganic SiO2-based protective coatings with and without added 3 μm glass particles were developed and tested for their corrosion and wear behavior of an stainless steel substrate (AISI316L). The corrosion resistance greatly increases by incorporating glass particles in the sols. The incorporation of particles in the coatings allows the synthesis of thicker crack-free coatings. On the other hand, the corrosion resistance increases for coatings with a higher organic content obtained at lower sintering temperature. These coatings are also highly stable in saline aqueous solutions. However, the wear resistance is badly affected by the hybrid character of the SiO2matrix. The optimum coating process in terms of corrosion and wear resistance, appears to be a hybrid system with a dense SiO2network achieved at intermediate sintering temperatures.

Chromosomal translocations entail the generation of gene fusions in solid mesenchymal tumors. Despite the successful identification of these specific and consistent genetic events, the nature of the intimate association between the gene fusion and the resulting phenotype is pending to understand. Herein these studies are reviewed using FUS-CHOP as a model to illustrate how the manipulation of their loci in the mouse has contributed to the current understanding in unique and unexpected ways. FUS-CHOP is a chimeric oncogene generated by the most common chromosomal translocation t(12;16)(q13;p11) associated to liposarcomas. The application of transgenic methods to the study of this sarcoma-associated FUS-CHOP gene fusion has provided insights into their in vivo functions and suggested mechanisms by which lineage selection may be achieved.

Summary: With the purpose of describing the MAb ior-R3’s kinetic behavior in disease state, this paper is focused on the study of this response using a human cancer (lung carcinoma cell line, H125) bearing nude mice animal model. This MAb was administered by a single 16 mg/Kg intravenous bolus dose and the blood samples were collected at several times ranging from 0 to 72 hours for serum drug quantification. The experimental data set was best fitted using a classical two-compartment mammilary pharmacokinetic (PK) model and the corresponding PK parameters were determined. Comparativel, the analysis of the more relevant physiologically-based PK parameters showed a significant enhancing of clearance as compound with the earlier reported study on healthy mice, increasing from 0.09 to 0.19 mL/h (p<0.01). However, the corresponding distribution volumes don’t seem to be altered by the tumor xenograft. We conclude that all of these evidences suggest a possible mechanism of receptor-mediated endocytosis (RME) as a major cause of this increased drug clearance which also contributed to the faster decrease of the drug disposition.

A synthetic route to furolabdanes from commercially available R-(+)-sclareolide is reported, with the specific aim of preparing (12R and 12S,15ξ)-12,15-dihydroxylabda-7,13-dien-16,15-olides (3 and 5) and (12R and 12S,16ξ)-12,16-dihydroxylabda-7,13-dien-15,16-olides (4 and 6). The key points of our approach are the use of Weinreb's amide 11 to join the furan ring to the terpenic unit. Photooxidation of the furan moiety of compounds 15 and 16, and of their acetates 19 and 20, has been used to built the hydroxybutenolide fragment. In this way the four possible isomers at the butenolide moiety, compounds 3−6, and their C-12 acetyl derivatives 21−24 have been obtained. On the basis of comparison of the spectral data (¹H NMR) of the synthetic peracetates 25−28 (derived from 21−24) with the reported data for the peracetate 2 (derived from the natural product 1), the relative configuration at carbon C-12 of the natural product has been corrected. Furthermore, the absolute configuration of the natural product 1, considered to belong to the enantio-series, has to be changed to the normal-series on the basis of the optical rotation obtained for the synthetic derivative.

Traumatic avulsion of the triceps brachii tendon is a rare injury. Clinical diagnosis shows that elbow extension against gravity is not possible. Radiologically, the lateral elbow may show the presence of flecks of avulsed osseous material from the olecranon (“flake sign”), which is almost pathognomonic of this lesion. The authors of the present study present a case of avulsion fracture treated with the attachment of bone suture anchors.

Background and aims: In patients presenting severe malabsorption, essential fatty acid (EFA) deficiency can be corrected by intravenous lipids, but EFA abnormalities persist. The purpose of this study was to evaluate the role of large resection of the small bowel or malabsorption on plasma phospholipid EFA profile. Methods: The plasma phospholipid EFA composition was measured by gas chromatography in home parenteral nutrition patients with (n=13) or without small bowel resection (n=7) and in 14 healthy subjects. Results: The two groups of patients had the same nutritional status and comparable amounts of intravenous fat. In both groups, plasma fatty acid concentrations were significantly different from those observed in healthy subjects without EFA deficiency. Among them: a decrease in 18:2 n-6, 22:5 n-3, 22:6 n-3 and an increase in 18:3 n-3, 20:4 n-6, 22:4 n-6. Moreover, arachidonic acid to linoleic acid ratio was higher in both groups of patients, suggesting a stimulation of the elongation and desaturation of 18:2 n-6. In multiple linear regression, 18:2 n-6 and 20:4 n-6 levels were not associated with the small bowel length, only 22:6 n-3 concentration was correlated with small bowel length.Conclusions: The patients with chronic intestinal failure on home parenteral nutrition presented specific change in their EFA and an increase in the n-6 fatty acid pathway. This could be related to the severe malabsorption.

Due to its antagonistic properties upon ligand-epidermal growth factor receptor (EGFr) interaction, the monoclonal antibody anti-EGFr ior EGF/r3 is considered a potential therapeutic agent against several epithelium-derived tumours. This paper affords further analysis of the relevant corporal interaction of this monoclonal antibody in terms of its pharmacodynamic properties, using nude mice, following a single bolus intravenous dose administration. The radio-receptor assay allows quantification of the serum ior EGF/r3 level. The dose selection procedure, according to the Kolmogorov-Smirnov test, suggested using doses of 12.5–16 mg kg−1for pharmacokinetic assessments. The experimental data were best fitted to a biexponential function (r2= 0.985), through the classical two-compartment open modelling approach. The model selection was corroborated by the AKAIKE information criteria, and also the SCHWARTZ and ESTRIPtest were used. The estimated pharmacokinetic parameters (e.g. = 34.65 h, Vc = 2.84 mL, Vss = 4.21 mL and CL = 0.09 mL h−1) bear out the strategies for the evaluation of the therapeutic application of this drug. Finally, the radio-receptor analysis has provided a rationale for the proposed serum monoclonal antibody ior EGF/r3 quantification to characterize its concentration-time course.

A key problem in the effective treatment of patients with cancer (both leukemia and solid tumors) is to distinguish between tumor and normal cells. This problem is the main reason why current treatments for cancer are often ineffective. There have been remarkable advances in our understanding of the molecular biology of cancer that provides new selective tumor destruction mechanisms. The molecular characterization of the tumorspecific chromosomal abnormalities has revealed that fusion proteins are the consequence in the majority of cancers. These fusion proteins result from chimeric genes created by the translocations, which form chimeric mRNA species that contain exons from the genes involved in the translocation. Obviously, these chimeric molecules are attractive therapeutic targets since they are unique to the disease (they only exist in the tumor cells but not in the normal cells of the patient), allowing the design of specific anti-tumor drugs. Inhibition of chimeric gene expression by anti-tumor agents specifically kills leukemic cells without affecting normal cells. As therapeutic agents targeting chimeric genes, zinc-finger proteins, antisense RNAs or hammerhead-based ribozymes have been used. All of these agents have some limitations, indicating that new therapeutic tools are required as gene inactivating agents that should be able to inhibit any chimeric fusion gene product. Recently, we have used the catalytic RNA subunit of RNase P from Escherichia coli, which can be specifically directed to cut any mRNA sequence, to specifically destroy tumor-specific fusion genes created as a result of chromosomal translocations. In this chapter, we will review the advances made to selectively destroy tumor cells through specific inhibition of products resulting from chromosomal translocations.