978 resultados para Long-Base-Line
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Rodrigues M.N., Oliveira G.B., Silva R.S.S, Tivane C.T., Albuquerque J.F.G., Miglino M.A. & Oliveira M.F. 2012. [Gross morphology and topography of the digestive apparatus in rheas (Rhea americana americana).] Macroscopia e topografia do aparelho digestorio de emas (Rhea americana americana). Pesquisa Veterinaria Brasileira 32(7):681-686. Departamento de Cirurgia, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Cidade Universitaria, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508270, Brazil. E-mail: marcio_medvet@hotmail.com Rheas are birds belonging to the ratites group and, among ostriches and emus, are the largest birds currently alive. In this work we studied the macroscopic aspects of rheas' digestive tract in order to provide important information to a better understanding of these birds' eating habits as well their anatomy. Twenty young animals aging between two and six months from the Centre for Wild Animals Multiplication (Cemas, scientific breeding license form Ibama no.1478912) were used. After dissection it was observed that their tongue was small and presented a rhomboid form, being disposed on the oral cavity floor, and inserted in its base by a frenulum. The esophagus was a rectilinear tube with elastic aspect and longitudinal elastic fibers, without dilation, which gives it an absence of crop. The proventriculus presented a fusiform form and the gastric ventricle showed and slightly oval form when filled, and was internally coated with a thick gastric cuticle. The small intestine was composed of three distinct regions: duodenum, jejunum and ileum. The duodenum had a light gray color and showed a "U" curved shaped. The jejunum was dark green, long and composed of several short loops arranged above each other. The ileum had a gray color and was connected with the jejunum. In ventral line to the rectum and cloaca, the ileum extended cranially, dorsally to the ascending duodenum. The large intestine was composed of two caeca, one right and one left, and colon-rectum and ileum were continuous with the cloaca. The structures of the rhea digestive tract resemble those described in the literature regarding to its shape and topography, even though rhea's caeca are well developed and relatively long.
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Visual tracking is the problem of estimating some variables related to a target given a video sequence depicting the target. Visual tracking is key to the automation of many tasks, such as visual surveillance, robot or vehicle autonomous navigation, automatic video indexing in multimedia databases. Despite many years of research, long term tracking in real world scenarios for generic targets is still unaccomplished. The main contribution of this thesis is the definition of effective algorithms that can foster a general solution to visual tracking by letting the tracker adapt to mutating working conditions. In particular, we propose to adapt two crucial components of visual trackers: the transition model and the appearance model. The less general but widespread case of tracking from a static camera is also considered and a novel change detection algorithm robust to sudden illumination changes is proposed. Based on this, a principled adaptive framework to model the interaction between Bayesian change detection and recursive Bayesian trackers is introduced. Finally, the problem of automatic tracker initialization is considered. In particular, a novel solution for categorization of 3D data is presented. The novel category recognition algorithm is based on a novel 3D descriptors that is shown to achieve state of the art performances in several applications of surface matching.
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Il raffreddamento stratosferico associato alla riduzione dell’ozono nelle regioni polari induce un rafforzamento dei venti occidentali nella bassa stratosfera, uno spostamento verso il polo e un’intensificazione del jet troposferico delle medie latitudini. Si riscontra una proiezione di questi cambiamenti a lungo termine sulla polarità ad alto indice di un modo di variabilità climatica, il Southern Annular Mode, alla superficie, dove i venti occidentali alle medie latitudini guidano la Corrente Circumpolare Antartica influenzando la circolazione oceanica meridionale e probabilmente l’estensione del ghiaccio marino ed i flussi di carbonio aria-mare nell’Oceano Meridionale. Una limitata rappresentazione dei processi stratosferici nei modelli climatici per la simulazione del passato e la previsione dei cambiamenti climatici futuri, sembrerebbe portare ad un errore nella rappresentazione dei cambiamenti troposferici a lungo termine nelle rispettive simulazioni. In questa tesi viene condotta un’analisi multi-model mettendo insieme i dati di output derivati da diverse simulazioni di modelli climatici accoppiati oceano-atmosfera, che partecipano al progetto CMIP5, con l'obiettivo di comprendere come le diverse rappresentazioni della dinamica stratosferica possano portare ad una differente rappresentazione dei cambiamenti climatici alla superficie. Vengono utilizzati modelli “High Top” (HT), che hanno una buona rappresentazione della dinamica stratosferica, e modelli “Low Top” (LT), che invece non ne hanno. I risultati vengono confrontati con le reanalisi meteorologiche globali disponibili (ERA-40). Viene mostrato come la rappresentazione e l’intensità del raffreddamento radiativo iniziale e di quello dinamico nella bassa stratosfera, nei modelli, siano i fattori chiave che controllano la successiva risposta troposferica, e come il raffreddamento stesso dipenda dalla rappresentazione della dinamica stratosferica. Si cerca inoltre di differenziare i modelli in base alla loro rappresentazione del raffreddamento radiativo e dinamico nella bassa stratosfera e alla risposta del jet troposferico. Nei modelli, si riscontra che il trend del jet nell'intera troposfera è significativamente correlato linearmente al raffreddamento stesso della bassa stratosfera.
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The present work reports the outcome of the GIMEMA CML WP study CML0811, an independent trial investigating nilotinib as front-line treatment in chronic phase chronic myeloid leukemia (CML). Moreover, the results of the proteomic analysis of the CD34+ cells collected at CML diagnosis, compared to the counterpart from healthy donors, are reported. Our study confirmed that nilotinib is highly effective in the prevention of the progression to accelerated/blast phase, a condition that today is still associated with high mortality rates. Despite the relatively short follow-up, cardiovascular issues, particularly atherosclerotic adverse events (AE), have emerged, and the frequency of these AEs may counterbalance the anti-leukemic efficacy. The deep molecular response rates in our study compare favorably to those obtained with imatinib, in historic cohorts, and confirm the findings of the Company-sponsored ENESTnd study. Considering the increasing rates of deep MR over time we observed, a significant proportion of patients will be candidate to treatment discontinuation in the next years, with higher probability of remaining disease-free in the long term. The presence of the additional and complex changes we found at the proteomic level in CML CD34+ cells should be taken into account for the investigation on novel targeted therapies, aimed at the eradication of the disease.
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Obiettivo del lavoro è quello di legare tra di loro due aspetti che storicamente sono sempre stati scollegati. Il primo è il lungo dibattito sul tema “oltre il PIL”, che prosegue ininterrottamente da circa mezzo secolo. Il secondo riguarda l’utilizzo dei sistemi di misurazione e valutazione della performance nel settore pubblico italiano. Si illustra l’evoluzione del dibattito sul PIL facendo un excursus storico del pensiero critico che si è sviluppato nel corso di circa cinquanta anni analizzando le ragioni assunte dagli studiosi per confutare l’utilizzo del PIL quale misura universale del benessere. Cogliendo questa suggestione l’Istat, in collaborazione con il CNEL, ha avviato un progetto per individuare nuovi indicatori da affiancare al PIL, in grado di misurare il livello non solo della crescita economica, ma anche del benessere sociale e sostenibile, con l’analisi degli indicatori riferiti a 12 domini di benessere individuati. Al progetto Istat-CNEL si è affiancato il progetto UrBES, promosso dall’Istat e dal Coordinamento dei sindaci metropolitani dell’ANCI, che hanno costituito una rete di città metropolitane per sperimentare la misurazione e il confronto sulla base di indicatori di benessere urbano equo e sostenibile, facendo proprio un progetto del Comune di Bologna e di Laboratorio Urbano (Centro di documentazione, ricerca e proposta sulle città), che ha sottoposto a differenti target un questionario on line, i cui risultati, con riferimento alle risposte fornite alle domande aperte, sono stati elaborati attraverso l’utilizzo di Taltac, un software per l’analisi dei testi, al fine di individuare i “profili” dei rispondenti, associando i risultati dell’elaborazione alle variabili strutturali del questionario. Nell’ultima parte i servizi e progetti erogati dal comune di Bologna sono stati associati alle dimensioni UrBES, per valutare l’impatto delle politiche pubbliche sulla qualità della vita e sul benessere dei cittadini, indicando le criticità legate alla mancanza di dati adeguati.
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Topiramate, which is commonly prescribed for seizure disorders and migraine prophylaxis, sometimes causes metabolic acidosis and hypokalemia. Since the effects of topiramate on acid-base balance and potassium levels have not been well explored in children, acid-base balance, anion gap and potassium were assessed in 24 patients (8 females and 16 males) aged between 4.6 and 19 years on topiramate for more than 12 months and in an age-matched control group. Plasma bicarbonate (21.7 versus 23.4 mmol/L; P<0.03), carbon dioxide pressure (39.7 versus 43.2mm Hg; P<0.05), and potassium (3.7 versus 4.0 mmol/L; P<0.03) were on the average lower and chloride (109 versus 107 mmol/L; P<0.03) higher in patients treated with topiramate than in controls. Blood pH, plasma sodium and the anion gap were similar in patients on topiramate and in controls. In patients on topiramate no significant correlation was observed between the dosage of this agent and plasma bicarbonate or potassium as well as between topiramate blood level and the mentioned electrolytes. In conclusion long-term topiramate treatment is associated with a mild, statistically significant tendency towards compensated normal anion gap metabolic acidosis and hypokalemia.
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Hemianopic patients make a systematic error in line bisection, showing a contra-lesional bias towards their blind side, which is the opposite of that in hemineglect patients. This error has been attributed variously to the visual field defect, to long-term strategic adaptation, or to independent effects of damage to extrastriate cortex. To determine if hemianopic bisection error can occur without the latter two factors, we studied line bisection in healthy subjects with simulated homonymous hemianopia using a gaze-contingent display, with different line-lengths, and with or without markers at both ends of the lines. Simulated homonymous hemianopia did induce a contra-lesional bisection error and this was associated with increased fixations towards the blind field. This error was found with end-marked lines and was greater with very long lines. In a second experiment we showed that eccentric fixation alone produces a similar bisection error and eliminates the effect of line-end markers. We conclude that a homonymous hemianopic field defect alone is sufficient to induce both a contra-lesional line bisection error and previously described alterations in fixation distribution, and does not require long-term adaptation or extrastriate damage.
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Context Long-term antiretroviral therapy (ART) use in resource-limited countries leads to increasing numbers of patients with HIV taking second-line therapy. Limited access to further therapeutic options makes essential the evaluation of second-line regimen efficacy in these settings. Objectives To investigate failure rates in patients receiving second-line therapy and factors associated with failure and death. Design, Setting, and Participants Multicohort study of 632 patients >14 years old receiving second-line therapy for more than 6 months in 27 ART programs in Africa and Asia between January 2001 and October 2008. Main Outcome Measures Clinical, immunological, virological, and immunovirological failure (first diagnosed episode of immunological or virological failure) rates, and mortality after 6 months of second-line therapy use. Sensitivity analyses were performed using alternative CD4 cell count thresholds for immunological and immunovirological definitions of failure and for cohort attrition instead of death. Results The 632 patients provided 740.7 person-years of follow-up; 119 (18.8%) met World Health Organization failure criteria after a median 11.9 months following the start of second-line therapy (interquartile range [IQR], 8.7-17.0 months), and 34 (5.4%) died after a median 15.1 months (IQR, 11.9-25.7 months). Failure rates were lower in those who changed 2 nucleoside reverse transcriptase inhibitors (NRTIs) instead of 1 (179.2 vs 251.6 per 1000 person-years; incidence rate ratio [IRR], 0.64; 95% confidence interval [CI], 0.42-0.96), and higher in those with lowest adherence index (383.5 vs 176.0 per 1000 person-years; IRR, 3.14; 95% CI, 1.67-5.90 for <80% vs ≥95% [percentage adherent, as represented by percentage of appointments attended with no delay]). Failure rates increased with lower CD4 cell counts when second-line therapy was started, from 156.3 vs 96.2 per 1000 person-years; IRR, 1.59 (95% CI, 0.78-3.25) for 100 to 199/μL to 336.8 per 1000 person-years; IRR, 3.32 (95% CI, 1.81-6.08) for less than 50/μL vs 200/μL or higher; and decreased with time using second-line therapy, from 250.0 vs 123.2 per 1000 person-years; IRR, 1.90 (95% CI, 1.19-3.02) for 6 to 11 months to 212.0 per 1000 person-years; 1.71 (95% CI, 1.01-2.88) for 12 to 17 months vs 18 or more months. Mortality for those taking second-line therapy was lower in women (32.4 vs 68.3 per 1000 person-years; hazard ratio [HR], 0.45; 95% CI, 0.23-0.91); and higher in patients with treatment failure of any type (91.9 vs 28.1 per 1000 person-years; HR, 2.83; 95% CI, 1.38-5.80). Sensitivity analyses showed similar results. Conclusions Among patients in Africa and Asia receiving second-line therapy for HIV, treatment failure was associated with low CD4 cell counts at second-line therapy start, use of suboptimal second-line regimens, and poor adherence. Mortality was associated with diagnosed treatment failure.
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Protein is an essential component for life, and its synthesis is mediated by codons in any organisms on earth. While some codons encode the same amino acid, their usage is often highly biased. There are many factors that can cause the bias, but a potential effect of mononucleotide repeats, which are known to be highly mutable, on codon usage and codon pair preference is largely unknown. In this study we performed a genomic survey on the relationship between mononucleotide repeats and codon pair bias in 53 bacteria, 68 archaea, and 13 eukaryotes. By distinguishing the codon pair bias from the codon usage bias, four general patterns were revealed: strong avoidance of five or six mononucleotide repeats in codon pairs; lower observed/expected (o/e) ratio for codon pairs with C or G repeats (C/G pairs) than that with A or T repeats (A/T pairs); a negative correlation between genomic GC contents and the o/e ratios, particularly for C/G pairs; and avoidance of C/G pairs in highly conserved genes. These results support natural selection against long mononucleotide repeats, which could induce frameshift mutations in coding sequences. The fact that these patterns are found in all kingdoms of life suggests that this is a general phenomenon in living organisms. Thus, long mononucleotide repeats may play an important role in base composition and genetic stability of a gene and gene functions.
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Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy associated with defective regulation of the alternative complement pathway. The prognosis for patients with aHUS is poor, and plasma exchange represents the first-line therapy. Eculizumab is a humanized monoclonal anti-C5 antibody that prevents the activation of the terminal complement pathway. Here, we report the case of a 9-year-old girl with frequent relapsing aHUS due to heterozygous factor H mutation who was initially treated with plasma exchange three times per week with 150% plasma exchange volume. This treatment frequently caused allergic reactions and school absences. Because any reduction in the frequency of plasma exchange immediately induced relapses of the aHUS, treatment with eculizumab, 600 mg every 2 weeks, was started and plasma exchange completely stopped. On this drug regimen the patient showed no evidence of disease activity during a period of more than 24 months. Renal function improved, proteinuria disappeared, the number of antihypertensive medications could be decreased, and the quality of life increased substantially. The inhibition of the terminal complement pathway by eculizumab was also confirmed by renal biopsy, which showed the absence of thrombotic microangiopathy 2 months after the initiation of eculizumab therapy. This case illustrates the long-term favorable outcome of aHUS with eculizumab treatment.
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Objectives. Latinos are the nation's largest minority group and will double in size by 2050. Their size coupled with the fact that Latinos do not constitute a separate race raises questions about Latinos' incorporation into the U. S. racial hierarchy. This article explores patterns of Latino racial identity formation, examining the determinants of racial identity. Methods. Using the 2006 Latino National Survey, I estimate multinomial logit and ordered probit models of identification choices. Results. Latino racial identity is strongly associated with several factors, including socioeconomic status, measures of perceived discrimination and commonality, and measures of acculturation/assimilation. Most Latinos have a broader, more complex understanding of race. Furthermore, some Latinos do believe that they occupy a unique position in the racial hierarchy. Conclusions. The results suggest that the color line W. E. DuBois argued has long divided our nation may eventually shift.
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Innate immunity represents the first line of defence against pathogens and plays key roles in activation and orientation of the adaptive immune response. The innate immune system comprises both a cellular and a humoral arm. Components of the humoral arm include soluble pattern recognition molecules (PRMs) that recognise pathogen-associated molecular patterns (PAMPs) and initiate the immune response in coordination with the cellular arm, therefore acting as functional ancestors of antibodies. The long pentraxin PTX3 is a prototypic soluble PRM that is produced at sites of infection and inflammation by both somatic and immune cells. Gene targeting of this evolutionarily conserved protein has revealed a nonredundant role in resistance to selected pathogens. Moreover, PTX3 exerts important functions at the cross-road between innate immunity, inflammation, and female fertility. Here, we review the studies on PTX3, with emphasis on pathogen recognition and cross-talk with other components of the innate immune system.
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Innate immunity represents the first line of defence against pathogens and plays key roles in the activation and orientation of the adaptive immune response. The innate immune system comprises both a cellular and a humoral arm. Components of the humoral arm include soluble pattern recognition molecules that recognize pathogen-associated molecular patterns and initiate the immune response in coordination with the cellular arm, therefore acting as functional ancestors of antibodies. Pentraxins are essential constituents of the humoral arm of innate immunity and represent a superfamily of highly conserved acute phase proteins, traditionally classified into short and long pentraxins. Pentraxin 3 (PTX3) is the prototypic member of the long pentraxins subfamily. As opposed to C-reactive protein, whose sequence and regulation have not been conserved during evolution from mouse to man, the evolutionary conservation of sequence, gene organization and regulation of PTX3 has allowed addressing its pathophysiological roles in genetically modified mice, in diverse conditions, ranging from infections to sterile inflammation, angiogenesis and female fertility. Despite this conservation, a number of predominantly non-coding polymorphisms have been identified in the PTX3 gene which, when associated in particular haplotypes, have been shown to be relevant in clinical conditions including infection and fertility. Here we review the studies on PTX3, with emphasis on pathogen recognition, tissue remodelling and crosstalk with other components of the innate immune system.
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The complementary Watson-Crick base-pairs, A:T and G:C, have long been recognized as pivotal to both the stability of the DNA double helix and replication/transcription. Recently, the replacement of the Watson-Crick base-pairs with other molecular entities has received considerable attention. In this tutorial review we highlight different approaches used to replace natural base-pairs and equip them with novel function. We also discuss the advantages that non-natural base-pairs convey with respect to practical applications.
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A computational study of line-focus generation was done using a self-written ray-tracing code and compared to experimental data. Two line-focusing geometries were compared, i.e., either exploiting the sagittal astigmatism of a tilted spherical mirror or using the spherical aberration of an off-axis- illuminated spherical mirror. Line focusing by means of astigmatism or spherical aberration showed identical results as expected for the equivalence of the two frames of reference. The variation of the incidence angle on the target affects the line-focus length, which affects the amplification length such that as long as the irradiance is above the amplification threshold, it is advantageous to have a longer line focus. The amplification threshold is physically dependent on operating parameters and plasma-column conditions and in the present study addresses four possible cases.