PDF superior Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

Figure 7. Corrosion rate isovalues for study zone U2-P1-P04; most values are very high. The very high corrosion rate values may have been caused by localized repairs done with uncompacted materials, which cause cracks and spalling between the new and pre-existing concrete. This is a very common effect at the concrete-steel interface in real structures. It arises from the “top-bar” effect in which adherence to the steel reinforcement decreases in the cover, particularly in thick concrete with inadequate compaction (P.R. Jeanty et al., 1988; A. Castel, 2006). It can also result from corrosion caused by galvanic current within the macrocell. This is caused by an electric connection between rebar exposed to different electrochemical surroundings, that is, passive steel in recently repaired zones and active steel in carbonated zones (J. Gulikers and M. Raupach, 2006; J. Warkus and M. Raupach, 2006). High galvanic currents result which lead to high corrosion levels according to RILEM recommended levels (A. Nasser et al., 2010).
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14 Lee mas

Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

This work presents and discuss the results of a corrosion inspection, as well as a repair proposal for the external walls of a reinforced concrete tower which is in the southern coast of the Veracruz state. The inspection included a drone guided damage survey together with physical, chemical, mechanical and electrochemical tests that allowed the concrete characterization and corrosion damage. The governing deterioration mechanism of the structure was carbonation of concrete. However, the sulfate emission in this industrial environment was reflected on the compressive resistance, cracks and delaminations. These conditions were taken into account on the proposed actions for repairing and extending the service life of the structure.
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14 Lee mas

Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

Evaluation of pathological problems associated with carbonation and sulfates in a concrete tower with more than 50 years in service

This work presents and discuss the results of a corrosion inspection, as well as a repair proposal for the external walls of a reinforced concrete tower which is in the southern coast of the Veracruz state. The inspection included a drone guided damage survey together with physical, chemical, mechanical and electrochemical tests that allowed the concrete characterization and corrosion damage. The governing deterioration mechanism of the structure was carbonation of concrete. However, the sulfate emission in this industrial environment was reflected on the compressive resistance, cracks and delaminations. These conditions were taken into account on the proposed actions for repairing and extending the service life of the structure.
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13 Lee mas

Frecuencia de virus respiratorios y caractersticas clnicas de nios que acuden a un hospital en Mxicoh

Frecuencia de virus respiratorios y caractersticas clnicas de nios que acuden a un hospital en Mxicoh

Objective. To describe the frequency of respiratory viruses and clinical characteristics in children with respiratory signs and symptoms in a tertiary care center in Mexico. Material and Methods. Patients with a clinical diagnosis of respiratory infection and a positive immunofluorescence result (Light Diagnostics) from January 2004 to October 2006 were in- cluded. Results. From the 986 nashopharyngeal samples, 138 (14%) were positive by immunofluorescence. The frequency was: 80% RSV, 8% parainfluenza 1, 5% parainfluenza 3, 2% ade- novirus, 2% influenza A, 1% parainfluenza 2 and 1% influenza B. Conclusions. Respiratory viruses were detected in 14% of samples tested. RSV was the most frequently identified virus and was associated with pneumonia and bronchiolitis in children younger than 3 years old.
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5 Lee mas

Factors associated to avascular necrosis of the femoral head and non-union in patients younger than 65 years old with displaced femoral neck fractures treated with reduction and internal fixation.

Factors associated to avascular necrosis of the femoral head and non-union in patients younger than 65 years old with displaced femoral neck fractures treated with reduction and internal fixation.

A review of all patients younger than 65 years old admitted to a single institution with the diagnosis of a displaced femoral neck fractures between January 1995 and December 2007 was performed. All these patients underwent reduction and internal fixation with cannulated screws; only patients who had two years or longer follow up were included in this study. The study included twenty-nine patients (22 males) with 29 fractures. In all cases, after routine radiographic examination with antero- posterior (AP) and axial views of the affected hip, a closed reduction was attempted with the patient in supine position on a fracture table. In 5 cases (17.2%) a satisfactory closed reduction of the fracture was obtained, whereas in
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5 Lee mas

Complications of Liver Resection in Geriatric Patients

Complications of Liver Resection in Geriatric Patients

older than 75 years. This is in agreement with the present trend of surgical solutions in older patients after sched- uled complex internal preparation. On the other hand, one needs to be cautious when using ‘aggressive therapies’ and ‘extended criteria’ in the aged. Ageing is associated with a myriad of physiological and functional changes that may compromise the ability of elderly patients to tolerate these therapies. Liver surgery is not without complications, and the need to balance the risks and costs against the potential improvement in survival in the elderly continues to leave many clinicians reluctant to propose surgical resection in these patients. 9
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8 Lee mas

Parte III Resumenes del V 99 al FP 167

Parte III Resumenes del V 99 al FP 167

The incidence of post-cholecystectomy bile leakage (PCBL), without bile duct injury, is 0.8-2%. Published studies have addressed the sourc- es, mainly cystic duct stump and subvesical duct leaks, and their management. As endoscopic, laparoscopic or laparotomy reinterven- tion, have obvious disadvantages, how can this complication be pre- vented? Aims and methods: To study the possible aetiological mech- anisms and the methods of preventing PCBL, prospective data from a large series of LC performed on one firm was analyzed. Dissection techniques and methods of securing the cystic duct and subvesical ducts were evaluated. Results: Subvesical ducts were encountered in 22 of 1,260 cases of LC (1.7%). Nine were secured with loops, seven were ligated and six were sutured. In our practice, Calot trian- gle and gallbladder dissection is carried out using only a blunt dis- secting forceps with flat jaws, the so called “duckbill”. This is used to open windows in the peritoneal reflection and the jaws open to create a plain. Sweeping the gallbladder wall away from the liver makes it possible to identify any accessory ducts before using diathermy. It is very likely that hook dissection would have caused some to leak, as the hook may transect or open accessory duct without identifying them, coagulating the open ends at the same time. This may explain the delay of 2-5 days in most reported series until necrosis and sloughing occur causing leakage. Only one case of asymptomatic bile leakage requiring reintervention was encountered (0.08%). The patient had dense adhesions obscuring the cystic pedicle, necessitating fundus – first dissection. The pedicle was thickened and short and the cystic duct and artery could not be separated. Two endoclips were applied. A subphrenic drain produced 500 mls of bile for 3 days and ERCP showed a cystic duct leak and a “fingerscrossed” appearance of the endoclips which had twisted due to the thickening of the pedicle. A stent was inserted, the leakage stopped and the total hospital stay was 6 days. The stent was removed six weeks later. Following this, endoclips were abandoned in favour of intracorporeal ligation of the cystic duct and artery. No postcholecystectomy was encountered in the last 850 cases. Conclusion: In spite of its considerable benefits, the laparoscopic era has brought about some practices alien to con- ventional surgical principles. Using diathermy hooks for dissection and metal clips to occlude structures which used to be ligated and the explosion in the use of ERCP to investigate and treat suspected cho- ledocholithiasis are but a few examples. Our techniques helped us to avoid a potential PCBL rate of 1.7%. Active search for subvesical accessory duct can reduce the incidence of post-operative bile leaks. Avoiding the use of endoclips and diathermy hooks may help to pre- vent this complication.
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18 Lee mas

Regulating personal mobility vehicles and cycles with more than two wheels in Barcelona

Regulating personal mobility vehicles and cycles with more than two wheels in Barcelona

They must respect the right of way of pedestrians, the natural heritage and the urban furniture. They must respect the indications of the signs provided, cyclist paths and the routes of the paved or unpaved areas, if there are any. They may not travel on flowerbeds or areas or zones with vegetation of any kind, or along any area prohibited by a sign.

6 Lee mas

Hiking Tourism in Baleares: current situation, possibilities of growth and conflicts of interest

Hiking Tourism in Baleares: current situation, possibilities of growth and conflicts of interest

Among the recreational trail, the best known is undoubtedly the Arxiduc Lluís Salvador. Built by the Arxiduc himself with the aim of preserving natural areas and at the same time allow a better understanding of nature through the construction of trails and attractions, allowing the contemplation of the Mallorcan landscape. Reached the island of Mallorca and in love with her, decided to buy a few possessions, becoming owner of much of the coast between Valldemossa and Deià. But the most important fact is that, from that time, these routes were designed and created with the intention that people can enjoy the landscape. This has already had a strong social value because
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27 Lee mas

Turismo y desarrollo local

Turismo y desarrollo local

variables that influence the ideal solutions are related to the image, the experience and the loyalty. To be precise, the variables that intervene are: the vineyard’s image prior to the visit, the price in relation to the perceived quality, the authenticity and originality of the vineyard, the possibility to return to the vineyard and the possibility of recommending it to friends or relatives. Observing the positive ideal solution, it can be seen that there has always been a segment which has evaluated as “very satisfied” all the attributes included in the measurement of the satisfaction of the wine tourism. While if we observe the negative ideal solution, it can be seen that this behaviour is not symmetrical and that the attributes which have been ranked worst by some of the segments (in the majority of cases, the wine tourist that have evaluated the image of the winery prior to the visit as a 5) are: the access to the vineyard, the winery’s facilities, the toilet facilities, the purchase of wines at reasonable prices, the wine tasting and the competent staff. For obvious reasons, these same attributes are the ones that present a higher heterogeneity of results between the two extreme ideal solutions.
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26 Lee mas

Sustainability of external imbalances in the OECD countries

Sustainability of external imbalances in the OECD countries

The problem of global external disequilibria relates in turn to the current international financial crisis, as discussed at length in Obstfeld and Rogoff (2010). Regarding the case of the European Union (EU), those countries with the highest current account disequilibria are those that have experienced a greater fall in their levels of domestic demand (Lane, 2010). Moreover, it has been argued that for these countries, usually the eurozone members with lower income levels, borrowing in international markets would have become easier before the beginning of the crisis. In fact, the greater financial integration, together with the adoption of the euro, would have meant a reduction in the cost of capital and the disappearance of exchange rate risk. As a result, this would have translated into both a decrease in saving and an increase in investment, and hence into a deterioration of the current account balance (Blanchard and Giavazzi, 2002). Even more, the prospects of convergence as regards the richer countries would have favour growth expectations in those countries, which contributed additionally to greater deficits; see Lane (2010). However, unlike the case of the US, where the size of the external deficit has led to a wide academic debate [see, e.g., Mann (2002), Blanchard, Giavazzi and Sa (2005), Edwards (2005) or Obstfeld and Rogoff (2007)], this has not been the norm in the European case, with a predominance of descriptive studies of a limited analytical content.
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22 Lee mas

Seales aterognicas tempranas en un rea de salud del municipio Consolacin del Sur

Seales aterognicas tempranas en un rea de salud del municipio Consolacin del Sur

Method: An observational descriptive cross-sectional study was conducted. The uni- verse consisted of 470 children, between 5 and 11 years of age, who receive primary health care in the Villa 1 People's Council of the 27 de Noviembre Polyclinic in Conso- lación del Sur, Pinar del Rio, Cuba. The sample was selected using the simple random method, and consisted of 148 children whose parents gave informed consent for their participation in the study. Sociodemographic, anthropometric and other variables of interest were studied, including blood pressure, birth weight, and a family history of hypertension and diabetes mellitus.
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14 Lee mas

Patterns of co occurrences in a killifish metacommunity are more related with body size than with species identity

Patterns of co occurrences in a killifish metacommunity are more related with body size than with species identity

Abstract Body size may be more important than species identity in determining species interactions and community structure. However, co-occurrence of organisms has commonly been analysed from a taxonomic perspective and the body size is rarely taken into account. On six sampling occasions, we analysed patterns of killifish co-occurrences in nestedness (tendency for less rich communities to be subsamples of the richest), checkerboard structure (tendency for species segregation), and modularity (tendency for groups to co-occur more frequently than random expectation) in a pond metacommunity located in Uruguay. We contrasted co-occurrence patterns among species and body size-classes (individuals from different species were combined into size categories). The analysis was performed at two spatial scales: ponds (communities) and sample units within ponds. Observed nestedness was frequently smaller than the null expectation, with significantly greater deviations for body size-classes than for species, and for sample units than for communities. At the sample unit level, individuals tended to segregate (i.e. clump into a checkerboard pattern) to a larger extent by body size rather than by taxonomy. Modularity was rarely detected, but nevertheless indicated a level of taxonomic organi- zation not evident in nestedness or checkerboard indices. Identification of the spatial scale and organization at which ecological forces determine community structure is a basic requirement for advancement of robust theory. In our study system, these ecological forces probably structured the community by body sizes of interacting organisms rather than by species identities.
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8 Lee mas

NEU screen shows high accuracy in detecting cognitive impairment in older persons living with HIV

NEU screen shows high accuracy in detecting cognitive impairment in older persons living with HIV

cognitive impairment in PLWH at different ages. To make our study sample more representative, we included PLWH with diverse clinical conditions. Consequently, a high rate (51%) of cognitive impairment was detected. A considerable percentage of participants in the sample were not receiving antiretroviral treatment (23%), were not virally suppressed (30%), and presented a potential confounding comorbidity for cognitive impairment (5%), all circumstances that could be related to this high frequency of cognitive disruption. Nonetheless, this rate of impairment was similar to that seen in other studies that have included PLWH with comorbidities and di- verse clinical conditions (Bonet et al., 2013; Heaton et al., 2010). The variables related to cognitive impair- ment that we found were mostly the same as those found traditionally in the field: low premorbid intellectual level, few years of education, presence of comorbidities, severity of those comorbidities, and low nadir CD41 T- cell count (Heaton et al., 2010; Morgan et al., 2012; Muñoz-Moreno et al., 2014; Patel et al., 2013).
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8 Lee mas

What a group of clinicians have learned about multiple personality disorder in Puerto Rico

What a group of clinicians have learned about multiple personality disorder in Puerto Rico

she had been in treatment for more than ten years with different therapists and diagnosis (schizophrenia. borderline personality disorder. complex-partial epilepsy). It was[r]

17 Lee mas

The transition from teaching to coordinating: a narrative study of ELT coordinators’ experiences

The transition from teaching to coordinating: a narrative study of ELT coordinators’ experiences

5.1.1 How do ELT teachers from the private sector obtain a coordinating position? As noted above, the main reason for choosing the topic of this research is personal interest. This first question was conceived after revising the literature on the topic. Previous studies on the transition from teaching to coordinating (Hockley 2004; Panferov, 2012) stated that promotion was the most common reason of why teachers move to coordination however, this had not been my case. When working as an ELT teacher I had not seen any teacher being promoted. Thus, I became interested in knowing if in our context there were other ways to become coordinators. The findings of this study partly support what previous studies reported. Results in this study indicate that in Mexico good teachers are frequently promoted to a coordination position. This might occur because of two reasons. On the one hand, traditionally outstanding employees are believed to have the competencies to perform successfully in a new or different position. On the other hand, stakeholders in educational institutions would rarely bring an outsider from a different field to deal with academic issues.
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72 Lee mas

Control of Molecular weight and polydispersity in polyethylene/needle like shaped clay nanocomposites obtained by in situ polymerization with metallocene catalysts

Control of Molecular weight and polydispersity in polyethylene/needle like shaped clay nanocomposites obtained by in situ polymerization with metallocene catalysts

anchor the MAO onto their structure than the laminar clays. This result is due to the former’s greater surface area and higher number of –OH groups, which promotes the anchoring reaction. Although fibrillar clays have a higher number of active sites for polymerization, their morphology promotes a significant increase in the length of the chains that grow over them. It was demonstrated that the nascent chains prefer the propagation reactions and the replication of the elongated shape of the fil- ler. Therefore, a non-isothermal polymerization method was designed with additional MAO to enable the control of the molecular weight. The results showed that the additional MAO increases the amount of short chains, which improves the rheological properties of the nanocomposites. On the other hand, it was shown that the increase in molar mass is inversely proportional to the number of active sites on the clay and directly proportional to the amount of initial filler added to the polymerization reactor.
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17 Lee mas

Factors associated with improvement in disability-adjusted life years in patients with HIV/AIDS

Factors associated with improvement in disability-adjusted life years in patients with HIV/AIDS

Specialist studies have shown that physical quality of life decreases as HIV progresses, as a result of symptoms and antiretroviral treatment [13]. As such, scores to measure patients' level of health, such as Disability-Adjusted Life Years (DALY), are more appropriate than mortality or sur- vival rates when it comes to studying the impact of this ill- ness or the associated "burden of disease", as they provide more information, taking into account not only that patients live for longer, but that their quality of life is also better. A patient's DALY represents the current value of the number of years of life free from disability that he or she will live, which are lost or gained as a result of premature death or disability during a certain year [14].
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9 Lee mas

Tokyo Tower and Tokyo Skytree: History and Symbolism in Contemporary Japan

Tokyo Tower and Tokyo Skytree: History and Symbolism in Contemporary Japan

during the final stages of construction of the Tokyo’s Skytree and after the earthquake. The story focused on a young couple with two small children living nearby the construction site, in one of the working- class apartment buildings of the area, and how a dog changed their lives for the best. The name given to the dog was “Skytree” in honor of the tower that the father and daughter admired and eagerly expected to be finished. The narrative made use of the Skytree and its building process, as well as the temperament and spirit of Skytree the dog, to refer to the hardships and setbacks in life and how a strong spirit can turn those adversities into opportunities to become a better self.
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11 Lee mas

Current therapies for chronic hepatitis B

Current therapies for chronic hepatitis B

by molecular cloning technique. The altered DNA (with mutations in the YMDD region) is transferred to tissue culture cells and the rate of viral production measured. Mutations in the YMDD region can be seen to present a certain resistance to lamivudine in vitro. However, this analysis also reveals that YMDD strains have a lower ca- pacity for replication than wild type HBV, no doubt be- cause the viral polymerase has less affinity with the sub- strates (nucleotides). There are also clinical information and experimental models demonstrating that wild type HBV reemerges as the dominant strain once treatment has ended and the selective pressure of lamivudine has disap- peared. 18 However, in some cases, variants in the YMDD
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6 Lee mas

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