978 resultados para SLOW


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The goal of this work was to move structural health monitoring (SHM) one step closer to being ready for mainstream use by the Iowa Department of Transportation (DOT) Office of Bridges and Structures. To meet this goal, the objective of this project was to implement a pilot multi-sensor continuous monitoring system on the Iowa Falls Arch Bridge such that autonomous data analysis, storage, and retrieval can be demonstrated. The challenge with this work was to develop the open channels for communication, coordination, and cooperation of various Iowa DOT offices that could make use of the data. In a way, the end product was to be something akin to a control system that would allow for real-time evaluation of the operational condition of a monitored bridge. Development and finalization of general hardware and software components for a bridge SHM system were investigated and completed. This development and finalization was framed around the demonstration installation on the Iowa Falls Arch Bridge. The hardware system focused on using off-the-shelf sensors that could be read in either “fast” or “slow” modes depending on the desired monitoring metric. As hoped, the installed system operated with very few problems. In terms of communications—in part due to the anticipated installation on the I-74 bridge over the Mississippi River—a hardline digital subscriber line (DSL) internet connection and grid power were used. During operation, this system would transmit data to a central server location where the data would be processed and then archived for future retrieval and use. The pilot monitoring system was developed for general performance evaluation purposes (construction, structural, environmental, etc.) such that it could be easily adapted to the Iowa DOT’s bridges and other monitoring needs. The system was developed allowing easy access to near real-time data in a format usable to Iowa DOT engineers.

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BACKGROUND AND PURPOSE: Sleep disordered breathing (SDB) is frequent in acute stroke patients and is associated with early neurologic worsening and poor outcome. Although continuous positive airway pressure (CPAP) effectively treats SDB, compliance is low. The objective of the present study was to assess the tolerance and the efficacy of a continuous high-flow-rate air administered through an open nasal cannula (transnasal insufflation, TNI), a less-intrusive method, to treat SDB in acute stroke patients. METHODS: Ten patients (age, 56.8 ± 10.7 years), with SDB ranging from moderate to severe (apnea-hypopnea index, AHI, >15/h of sleep) and on a standard sleep study at a mean of 4.8 ± 3.7 days after ischemic stroke (range, 1-15 days), were selected. The night after, they underwent a second sleep study while receiving TNI (18 L/min). RESULTS: TNI was well tolerated by all patients. For the entire group, TNI decreased the AHI from 40.4 ± 25.7 to 30.8 ± 25.7/h (p = 0.001) and the oxygen desaturation index >3% from 40.7 ± 28.4 to 31 ± 22.5/h (p = 0.02). All participants except one showed a decrease in AHI. The percentage of slow-wave sleep significantly increased with TNI from 16.7 ± 8.2% to 22.3 ± 7.4% (p = 0.01). There was also a trend toward a reduction in markers of sleep disruption (number of awakenings, arousal index). CONCLUSIONS: TNI improves SDB indices, and possibly sleep parameters, in stroke patients. Although these changes are modest, our findings suggest that TNI is a viable treatment alternative to CPAP in patients with SDB in the acute phase of ischemic stroke.

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Super- and co-infection with HIV-1 are generally associated with accelerated disease progression. We report on the outcome of super-infection in two HIV-1 infected individuals previously known as elite controllers. Both presented an acute retroviral syndrome following super-infection and showed an immuno-virological progression thereafter. Host genotyping failed to reveal any of the currently recognized protective factors associated with slow disease progression. This report indicates that elite controllers should be informed of the risk of super-infection, and illustrates the complexity of mounting broad anti-HIV immunity.

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Kinetic parameters of T cell receptor (TCR) interactions with its ligand have been proposed to control T cell activation. Analysis of kinetic data obtained has so far produced conflicting insights; here, we offer a consideration of this problem. As a model system, association and dissociation of a soluble TCR (sT1) and its specific ligand, an azidobenzoic acid derivative of the peptide SYIPSAEK-(ABA)I (residues 252-260 from Plasmodium berghei circumsporozoite protein), bound to class I MHC H-2K(d)-encoded molecule (MHCp) were studied by surface plasmon resonance. The association time courses exhibited biphasic patterns. The fast and dominant phase was assigned to ligand association with the major fraction of TCR molecules, whereas the slow component was attributed to the presence of traces of TCR dimers. The association rate constant derived for the fast phase, assuming a reversible, single-step reaction mechanism, was relatively slow and markedly temperature-dependent, decreasing from 7.0 x 10(3) at 25 degrees C to 1.8 x 10(2) M(-1).s(-1) at 4 degrees C. Hence, it is suggested that these observed slow rate constants are the result of unresolved elementary steps of the process. Indeed, our analysis of the kinetic data shows that the time courses of TCR-MHCp interaction fit well to two different, yet closely related mechanisms, where an induced fit or a preequilibrium of two unbound TCR conformers are operational. These mechanisms may provide a rationale for the reported conformational flexibility of the TCR and its unusual ligand recognition properties, which combine high specificity with considerable crossreactivity.

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The present study describes some of the applications of ultrasound in bone surgery, based on the presentation of two clinical cases. The Piezosurgery® ultrasound device was used (Tecnología Mectron Medical, Carasco, Italy). In one case the instrument was used to harvest a chin bone graft for placement in a bone defect at level 1.2, while in the other case a bony window osteotomy was made in the external wall of the maxillary sinus, in the context of a sinus membrane lift procedure. The Piezosurgery® device produces specific ultrasound frequency modulation (25-29 kHz), and has been designed to secure increased precision in application to bone surgery. This instrument produces selective sectioning of the mineralized bone structures, and causes less intra- and postoperative bleeding. One of the advantages of the Piezosurgery® device is that it can be used for maxillary sinus lift procedures in dental implant placement. In this context it considerably lessens the risk of sinus mucosa laceration by preparing the bony window in the external wall of the upper maxilla, and can be used to complete the lifting maneuver. The use of ultrasound in application to hard tissues can be regarded as a slow technique compared with the conventional rotary instruments, since it requires special surgical skill and involves a certain learning curve.

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The City of West Union has been selected by Iowa Department of Economic Development as a Green Pilot Community. A major project within this designation is the reconstruction of the downtown business district public infrastructure in a sustainable, innovative, and replicable way. A key component of this project is replacement of the impermeable street and sidewalk surfacing with a porous paver system. This system, along with bio-retention cells in intersection bumpouts and sidewalk planters, will infiltrate, then cleanse and cool the storm water prior to a very slow discharge rate to Otter Creek. The project area will see a 95% reduction in peak discharge rate for a 100 year storm and a 20% reduction in runoff volume. West Union is located within the Otter Creek watershed, a designated cold water trout stream just below the city. Fayette County Soil and Water Conservation District and IDNR consider improvement of the water quality of Otter Creek to be very important. This reconstruction of downtown West Union in a sustainable manner will be the start of an overall Otter Creek watershed improvement project.

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With the Saylor Creek Watershed Improvement Project, Iowa Heartland RC&D and other area stakeholders have an opportunity to display how "best management practices" (BMPs) can reduce storm water runoff and improve the quality of that runoff in an urban setting. Conservation design is a uew approach to storm water management that addresses the negative impacts of storm water runoff and turns them into a positive. The master plan for the Prairie Trail development surrounding the watershed project will incorporate bioretention cells, bioswales, buffer strips, rain gardens, as well as native plant landscaping to slow storm water runoff and naturally clean sediment out of the water before it reaches Saylor Creek. In addition to conservation design elements, the project will utilize storm water detention ponds and creek bed restoration to develop a complete storm water "treatment train" system within Prairie Trail. The extensive use of conservation storm water management for Prairie Trail is unique for urban development in Iowa.

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Although metabolic syndrome (MS) and systemic lupus erythematosus (SLE) are often associated, a common link has not been identified. Using the BWF1 mouse, which develops MS and SLE, we sought a molecular connection to explain the prevalence of these two diseases in the same individuals. We determined SLE- markers (plasma anti-ds-DNA antibodies, splenic regulatory T cells (Tregs) and cytokines, proteinuria and renal histology) and MS-markers (plasma glucose, non-esterified fatty acids, triglycerides, insulin and leptin, liver triglycerides, visceral adipose tissue, liver and adipose tissue expression of 86 insulin signaling-related genes) in 8-, 16-, 24-, and 36-week old BWF1 and control New-Zealand-White female mice. Up to week 16, BWF1 mice showed MS-markers (hyperleptinemia, hyperinsulinemia, fatty liver and visceral adipose tissue) that disappeared at week 36, when plasma anti-dsDNA antibodies, lupus nephritis and a pro-autoimmune cytokine profile were detected. BWF1 mice had hyperleptinemia and high splenic Tregs till week 16, thereby pointing to leptin resistance, as confirmed by the lack of increased liver P-Tyr-STAT-3. Hyperinsulinemia was associated with a down-regulation of insulin related-genes only in adipose tissue, whereas expression of liver mammalian target of rapamicyn (mTOR) was increased. Although leptin resistance presented early in BWF1 mice can slow-down the progression of autoimmunity, our results suggest that sustained insulin stimulation of organs, such as liver and probably kidneys, facilitates the over-expression and activity of mTOR and the development of SLE.

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BACKGROUND: Synthesis of the Staphylococcus aureus peptidoglycan pentaglycine interpeptide bridge is catalyzed by the nonribosomal peptidyl transferases FemX, FemA and FemB. Inactivation of the femAB operon reduces the interpeptide to a monoglycine, leading to a poorly crosslinked peptidoglycan. femAB mutants show a reduced growth rate and are hypersusceptible to virtually all antibiotics, including methicillin, making FemAB a potential target to restore beta-lactam susceptibility in methicillin-resistant S. aureus (MRSA). Cis-complementation with wild type femAB only restores synthesis of the pentaglycine interpeptide and methicillin resistance, but the growth rate remains low. This study characterizes the adaptations that ensured survival of the cells after femAB inactivation. RESULTS: In addition to slow growth, the cis-complemented femAB mutant showed temperature sensitivity and a higher methicillin resistance than the wild type. Transcriptional profiling paired with reporter metabolite analysis revealed multiple changes in the global transcriptome. A number of transporters for sugars, glycerol, and glycine betaine, some of which could serve as osmoprotectants, were upregulated. Striking differences were found in the transcription of several genes involved in nitrogen metabolism and the arginine-deiminase pathway, an alternative for ATP production. In addition, microarray data indicated enhanced expression of virulence factors that correlated with premature expression of the global regulators sae, sarA, and agr. CONCLUSION: Survival under conditions preventing normal cell wall formation triggered complex adaptations that incurred a fitness cost, showing the remarkable flexibility of S. aureus to circumvent cell wall damage. Potential FemAB inhibitors would have to be used in combination with other antibiotics to prevent selection of resistant survivors.

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Using the blackfold approach, we study new classes of higher-dimensional rotating black holes with electric charges and string dipoles, in theories of gravity coupled to a 2-form or 3-form field strength and to a dilaton with arbitrary coupling. The method allows to describe not only black holes with large angular momenta, but also other regimes that include charged black holes near extremality with slow rotation. We construct explicit examples of electric rotating black holes of dilatonic and non-dilatonic Einstein-Maxwell theory, with horizons of spherical and non-spherical topology. We also find new families of solutions with string dipoles, including a new class of prolate black rings. Whenever there are exact solutions that we can compare to, their properties in the appropriate regime are reproduced precisely by our solutions. The analysis of blackfolds with string charges requires the formulation of the dynamics of anisotropic fluids with conserved string-number currents, which is new, and is carried out in detail for perfect fluids. Finally, our results indicate new instabilities of near-extremal, slowly rotating charged black holes, and motivate conjectures about topological constraints on dipole hair.

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The role of endothelin (ET) receptors was tested in volume-stimulated atrial natriuretic factor (ANF) secretion in conscious rats. Mean ANF responses to slow infusions (3 x 3.3 ml/8 min) were dose dependently reduced (P < 0.05) by bosentan (nonselective ET-receptor antagonist) from 64.1 +/- 18.1 (SE) pg/ml (control) to 52.6 +/- 16.1 (0.033 mg bosentan/rat), 16.1 +/- 7.6 (0. 33 mg/rat), and 11.6 +/- 6.5 pg/ml (3.3 mg/rat). The ET-A-receptor antagonist BQ-123 (1 mg/rat) had no effect relative to DMSO controls, whereas the putative ET-B antagonist IRL-1038 (0.1 mg/rat) abolished the response. In a second protocol, BQ-123 (>/=0.5 mg/rat) nonsignificantly reduced the peak ANF response (106.1 +/- 23.0 pg/ml) to 74.0 +/- 20.5 pg/ml for slow infusions (3.5 ml/8.5 min) but reduced the peak response (425.3 +/- 58.1 pg/ml) for fast infusions (6.6 ml/1 min) by 49.9% (P < 0.001) and for 340 pmoles ET-1 (328.8 +/- 69.5 pg/ml) by 83.5% (P < 0.0001). BQ-123 abolished the ET-1-induced increase in arterial pressure (21.8 +/- 5.2 mmHg at 1 min). Changes in central venous pressure were similar for DMSO and BQ-123 (slow: 0.91 and 1.14 mmHg; fast: 4.50 and 4.13 mmHg). The results suggest 1) ET-B receptors mainly mediate the ANF secretion to slow volume expansions of <1.6%/min; and 2) ET-A receptors mainly mediate the ANF response to acute volume overloads.

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The arenavirus Lassa virus (LASV) causes a severe hemorrhagic fever with high mortality in humans. Antigen-presenting cells, in particular dendritic cells (DCs), are early and preferred targets of LASV, and their productive infection contributes to the virus-induced immunosuppression observed in fatal disease. Here, we characterized the role of the C-type lectin DC-specific ICAM-3-grabbing nonintegrin (DC-SIGN) in LASV entry into primary human DCs using a chimera of the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) expressing the LASV glycoprotein (rLCMV-LASVGP). We found that differentiation of human primary monocytes into DCs enhanced virus attachment and entry, concomitant with the upregulation of DC-SIGN. LASV and rLCMV-LASVGP bound to DC-SIGN via mannose sugars located on the N-terminal GP1 subunit of LASVGP. We provide evidence that DC-SIGN serves as an attachment factor for rLCMV-LASVGP in monocyte-derived immature dendritic cells (MDDC) and can accelerate the capture of free virus. However, in contrast to the phlebovirus Uukuniemi virus (UUKV), which uses DC-SIGN as an authentic entry receptor, productive infection with rLCMV-LASVGP was less dependent on DC-SIGN. In contrast to the DC-SIGN-mediated cell entry of UUKV, entry of rLCMV-LASVGP in MDDC was remarkably slow and depended on actin, indicating the use of different endocytotic pathways. In sum, our data reveal that DC-SIGN can facilitate cell entry of LASV in human MDDC but that its role seems distinct from the function as an authentic entry receptor reported for phleboviruses.

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Leprosy is a contagious and chronic systemic granulomatous disease caused by Mycobacterium leprae (Hansen"s bacillus). It is transmitted from person to person and has a long incubation period (between two and six years). The disease presents polar clinical forms (the"multibacillary" lepromatous leprosy and the"paucibacillary" tuberculoid leprosy), as well as other intermediate forms with hybrid characteristics. Oral manifestations usually appear in lepromatous leprosy and occur in 20-60% of cases. They may take the form of multiple nodules (lepromas) that progress to necrosis and ulceration. The ulcers are slow to heal, and produce atrophic scarring or even tissue destruction. The lesions are usually located on the hard and soft palate, in the uvula, on the underside of the tongue, and on the lips and gums. There may also be destruction of the anterior maxilla and loss of teeth. The diagnosis, based on clinical suspicion, is confirmed through bacteriological and histopathological analyses, as well as by means of the lepromin test (intradermal reaction that is usually negative in lepromatous leprosy form and positive in the tuberculoid form). The differential diagnosis includes systemic lupus erythematosus, sarcoidosis, cutaneous leishmaniasis and other skin diseases, tertiary syphilis, lymphomas, systemic mycosis, traumatic lesions and malignant neoplasias, among other disorders. Treatment is difficult as it must be continued for long periods, requires several drugs with adverse effects and proves very expensive, particularly for less developed countries. The most commonly used drugs are dapsone, rifampicin and clofazimine. Quinolones, such as ofloxacin and pefloxacin, as well as some macrolides, such as clarithromycin and minocyclin, are also effective. The present case report describes a patient with lepromatous leprosy acquired within a contagious family setting during childhood and adolescence

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From 6 to 8 November 1982 one of the most catastrophic flash-flood events was recorded in the Eastern Pyrenees affecting Andorra and also France and Spain with rainfall accumulations exceeding 400 mm in 24 h, 44 fatalities and widespread damage. This paper aims to exhaustively document this heavy precipitation event and examines mesoscale simulations performed by the French Meso-NH non-hydrostatic atmospheric model. Large-scale simulations show the slow-evolving synoptic environment favourable for the development of a deep Atlantic cyclone which induced a strong southerly flow over the Eastern Pyrenees. From the evolution of the synoptic pattern four distinct phases have been identified during the event. The mesoscale analysis presents the second and the third phase as the most intense in terms of rainfall accumulations and highlights the interaction of the moist and conditionally unstable flows with the mountains. The presence of a SW low level jet (30 m s-1) around 1500 m also had a crucial role on focusing the precipitation over the exposed south slopes of the Eastern Pyrenees. Backward trajectories based on Eulerian on-line passive tracers indicate that the orographic uplift was the main forcing mechanism which triggered and maintained the precipitating systems more than 30 h over the Pyrenees. The moisture of the feeding flow mainly came from the Atlantic Ocean (7-9 g kg-1) and the role of the Mediterranean as a local moisture source was very limited (2-3 g kg-1) due to the high initial water vapour content of the parcels and the rapid passage over the basin along the Spanish Mediterranean coast (less than 12 h).

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Background: Pre-existing psychological factors can strongly influence coping with type 1 diabetes mellitus and interfere with self-monitoring. Psychiatric disorders seem to be positively associated with poor metabolic control. We present a case of extreme compulsive blood testing due to obsessive fear of hypoglycemia in an adolescent with type 1 diabetes mellitus. Case report: Type 1 diabetes mellitus (anti GAD-antibodies 2624 U/l, norm < 9.5) was diagnosed in a boy aged 14.3 years [170 cm (+ 0.93 SDS), weight 50.5 kg (+ 0.05 SDS)]. Laboratory work-up showed no evidence for other autoimmune disease. Family and past medical history were unremarkable. Growth and developmental milestones were normal. Insulin-analog based basal-bolus regime was initiated, associated to standard diabetic education. Routine psychological evaluation performed at the onset of diabetes revealed intermittent anxiety and obsessivecompulsive traits. Accordingly, a close psychiatric follow-up was initiated for the patient and his family. An adequate metabolic control (HbA1c drop from >14 to 8%) was achieved within 3 months, attributed to residual -cell function. In the following 6 months, HbA1c rose unexpectedly despite seemingly adequate adaptations of insulin doses. Obsessive fear of hypoglycemia leading to a severe compulsive behavior developed progressively with as many as 68 glycemia measurements per day (mean over 1 week). The patient reported that he could not bear leaving home with glycemia < 15 mmol/l, ending up with school eviction and severe intra-familial conflict. Despite intensive psychiatric outpatient support, HbA1c rose rapidly to >14% with glycemia-testing reaching peaks of 120 tests/day. The situation could only be discontinued through psychiatric hospitalization with intensive behavioral training. As a result, adequate metabolic balance was restored (HbA1c value: 7.1 %) with acceptable 10-15 daily glycemia measurements. Discussion: The association of overt psychiatric disorders to type 1 diabetes mellitus is very rare in the pediatric age group. It can lead to a pathological behavior with uncontrolled diabetes. Such exceptional situations require long-term admissions with specialized psychiatric care. Slow acceptation of a "less is better" principle in glycemia testing and amelioration of metabolic control are difficult to achieve.