Top PDF Sensores electroquímicos aplicados al estudio de la corrosión en estructuras de hormigón armado

All patients underwent standard four port laparoscopic cholecystectomy with initial para-umbilical camera port inserted using Hasson technique, a further 10 mm epigas- tric port and two 5 mm ports on right side were inserted under direct vision. Once the gallbladder was dissected free, it was retrieved through the umbilical port (either using a retrieval bag or not) under direct laparoscopic visualisation by moving the camera into the epigastric port. The gall- bladder was not aspirated, and stones were left intact within the gallbladder. In cases where the specimen was too large for extraction the facial incision was increased to facilitate extraction. Standard prophylactic antibiotics included single dose of 1.2 g Co-Amoxiclav at the time of induction, with patients who were known penicillin allergic receiving 1.5 g Cefuroxime instead. There was no protocol in place for pre-operative bathing and all patients were admitted to the hospital on the day of their procedure. Umbilical port site closure was with polyglyconate absorb-able sutures (0-Maxon). Skin incisions were closed with either metal skin clips or a subcuticular suture using 4-0 monocryl.

belonged those in whom retrieval bag was used. Among the control, 26.3% participants had infection while in the study group only one participant (4.5%) had infection and the difference was statistically significant (P = 0.049). Concurring this are the findings from Majid et al (22) who found that among those post LC surgery patients with superficial wound infections, 57% patients were in the group in whom retrieval bag was not used compared with those in whom retrieval bag was used (43%). Wound infections can be prevented by; appropriate administration of antibiotic prophylaxis, sterile techniques and the use of specimen endobags for specimen extraction (23). Bile leakage and choleperitonitis after open cholecystectomy is rare but its rate increases in Machado et al (24). reported that nearly 50% of the cases with complications had bile leakage, while Amir D et al.25 reported in 1.4% of patients. However, in our study a higher proportion of bile leak was noted during the operation. This was more participants of the study group (18.2%) than the control group (10.5%).

In order to avoid surgical site contamination from bile and stone spillage, surgeons pay attention not to open the gallbladder during dissection from the liver bed and retrieval from the abdominal cavity. Depending on the surgeon’s preference, a retrieval bag is used to extract the gallbladder through a trocar incision [2]. Endoscopic bags should be used when gallbladder cancer is sus- pected, in order to minimize the risk of tumor cell dis- semination [3] and in case of acute cholecystitis to avoid spillage of infected bile, stones or pus [4–6]. As a matter of fact, endoscopic bags are commonly used also in elective cholecystectomy despite increased costs and no sound evidence in their favor [7–9]. Are retrieval bags actually useful in preventing wound infections in elective laparoscopic cholecystectomy?

Due to budgetary constraints and increasing bed pres- sures, NHS practice patterns should confer the optimum utilization of resources. As this study is not proposing a new alternative treatment, advocating an early procedure will have little effect on the redeployment of resources. Performing laparoscopic cholecystectomies within a week of presentation may help to alleviate strain on resources because it is associated with significantly fewer readmis- sions and reduced duration of hospital stay. 15,16 Shorter

is to extract a summary of an item maintaining the most important ideas while significantly reducing the size. Examples of summaries that are often part of any item are titles, table of contents, and abstracts with the abstract being the closest. The abstract can be used to represent the item for search purposes or as a way for a user to determine the utility of an item without having to read the complete item. It is not feasible to automatically generate a coherent narrative summary of an item with proper discourse, abstraction and language usage (Sparck Jones-93). Restricting the domain of the item can significantly improve the quality of the output (Paice-93, Reimer-88). The more restricted goals for much of the research is in finding subsets of the item that can be extracted and concatenated (usually extracting at the sentence level) and represents the most important concepts in the item. There is no guarantee of readability as a narrative abstract and it is seldom achieved. It has been shown that extracts of approximately 20 per cent of the complete item can represent the majority of significant concepts (Morris-92). Different algorithms produces different summaries. Just as different humans create different abstracts for the same item, automated techniques that generate different summaries does not intrinsically imply major deficiencies between the summaries. Most automated algorithms approach summarization by calculating a score for each sentence and then extracting the sentences with the highest scores. Some examples of the scoring techniques are use of rhetorical relations (e.g., reason, direction, contrast: see Miike-94 for experiments in Japanese), contextual inference and syntactic coherence using cue words (Rush-71), term location (Salton-83), and statistical weighting properties discussed in Chapter 5. There is no overall theoretic basis for the approaches leading to many heuristic algorithms. Kupiec et al. are pursuing statistical classification approach based upon a training set reducing the heuristics by focusing on a weighted combination of criteria to produce “optimal” scoring scheme (Kupiec-95). They selected the following five feature sets as a basis for their algorithm:

Coordination refers to the construction of phrases from individual terms. Two distinct coordination options are recognized in thesauri: precoordination and post-coordination. A precoordinated thesaurus is one that can contain phrases. Consequently, phrases are available for indexing and retrieval. A postcoordinated thesaurus does not allow phrases. Instead, phrases are constructed while searching. The choice between the two options is difficult. The advantage in precoordination is that the vocabulary is very precise, thus reducing ambiguity in indexing and in searching. Also, commonly accepted phrases become part of the vocabulary. However, the disadvantage is that the searcher has to be aware of the phrase construction rules employed. Thesauri can adopt an intermediate level of coordination by allowing both phrases and single words. This is typical of manually constructed thesauri. However, even within this group there is significant variability in terms of coordination level. Some thesauri may emphasize two or three word phrases, while others may emphasize even larger sized phrases. Therefore, it is insufficient to state that two thesauri are similar simply because they follow

Cholecystitis is inflammation of the gallbladder. Symptoms include right upper abdominal pain, nausea, vomiting, and occasionally fever. The pain lasts longer in cholecystitis than in a typical biliary es of cholecystitis are common. During this study 229 patients were admitted with chronic cholecystitis of which 12 patients were excluded before randomization. The remaining 217 were randomized with 106 in the group A and 106 in group B. 5 xcluded because of open conversion in both the groups (2 in group A and 3 in group No significant differences existed between the 2 groups regarding sex, age; body mass index and ASA score. Also, the duration of LC surgery, incidence of intraoperative gallbladder operative bleeding from either cystic artery or gall bladder fossa and mean postoperative hospital stay were found not significantly different The parameters studied were age group, placement of drains, bile leak, hospital stay, Asepsis score, Surgical site infections, postoperative antibiotic used (after 24 hrs). In SSI in Group A, 95 (89.6%) had no SSI and 11 (superficial 8, deep 2, organ specific 1, total 10.4%) had SSI. In Group B, 96 (90.6%) had no SSI and 10 (superficial 7, deep 2, organ specific 1, total 9.4%) had SSI (p value 0.818). In both the groups the difference in the incidence of surgical site infections was not ficant.Hence prophylactic antibiotics do not reduce the risk of infective complications in patients undergoing laparoscopic cholecystectomy in low risk group of patients.

This study showed that operating times and severity of adhesions at the gallbladder area were increased in delayed group in whom LC was performed 4 weeks after ERCP. In the present study, the mean operative time in group I was 45.0 ± 12.4 min and in group II was 57.4±18.8 min, i.e. the mean operative time in the early group is shorter than that of the delayed group and this is in concordance with with the results of the study carried out by Csendes et al 25 . The operating time was longer in Group II patients who underwent delayed cholecystectomy, mostly attributed to scarring and fibrosis of the biliary tree and gallbladder area. Significantly higher levels of adhesions encountered during surgery have been reported for patients who underwent ERCP (Chandio, 2009; Schachter, 2000). This finding is corroborated in in present study, in which a significantly higher grade of adhesions was encountered in patients undergoing LC 4 weeks after ERCP. A causal relationship between ERCP and operative difficulty remains a controversial subject. ERCP is most commonly done for patients in whom biliary pancreatitis and cholangitis develop, who are likely to have peripancreatic and pericholedochal fibrosis. This would be reflected in the adhesion grading. ERCP itself may injure the structures within the hepatoduodenal ligament either because of instrumentation of the biliary duct or as a direct effect of the contrast, causing increased periportal inflammation and scarring. (Boerma, 2002 and Bostanci, 2010). It has been reported that earlier LC is less challenging and can be achieved without significant adverse events (Reinders, 2010; Bostanci, 2010 and Van Baal, 2012). The difference between the two groups comes from the difficulty in the surgery. There were more pericholecystic

LC has reached an important turning point with the development of single-incision laparoscopic surgery. Most reported techniques utilize a special purpose-made access port and articulating instruments, rendering the procedure costly and difficult to learn. This article documents the feasibility of single-incision laparoscopic cholecystectomy and provides a stepwise description of the SILS cholecystectomy technique using all straight instruments without the need for a special port. The clinical advantages of this approach may eventually require a randomized controlled trial to compare it with conventional laparoscopic cholecystectomy. The major advan- tage of this method is improved cosmetics, without any visible abdominal scars. The disadvantages of SILS include the conflict between the operative instruments, and the camera and the smaller degree of instrument triangulation compared to that of conventional laparoscopic surgery. Despite the limitations of SILS, we were able to perform our operation in seven cases. All procedures were completed successfully within a reasonable time (Figure 3).

Ultrasonography is accurate in the diagnosis of all gallbladder stones (97% in elective situation and 80% in presence of acute cholecystitis). But common bile duct stones are missed frequently (sensitivity 15-40%). The detection of CBD stone is impeded by presence of gas in duodenum. CBD dilatation is identified accurately with up to 90% accuracy. Recent advance with the introduction of tissue harmonic imaging (THI) gives better visualization of fluid filled structure and reduced artifacts and enhanced contrast resolution.

Considering the tradeoff of clustering and ranked list, Allan, Leuski, Swan, and Byrd (2001) combined clustering with the traditional ranked list to overcome the problems of only providing ranked list or clustering and have the benefits of the two techniques. They first evaluated the effectiveness of two versions of the system in the TREC 6 Interactive Track: one with and another one without visualization that combines a ranked list with clustering. There was no significant advantage to using the visualization, although the researchers observed examples where the visualization offered valuable help. According to Allan et al. (2001), the reasons for the results cannot be detected in the Interactive Track environment because the value of visualization might be obscured by other variations in users and systems. A new system was built to incorporate interdocument similarity visualization to the ranked list. Using the TREC collection and relevance judgments, they conducted a noninteractive study evaluating the performance of the ranked list, relevance feed- back, and the combination of ranked list and clustering. The results showed that the combination outperformed the ranked list. This approach is as powerful as the relevance feedback approach, but much easier for searchers to understand. In TREC10, Craswell, Hawking, Wilkinson, and Wu (2002) further investigated the correlation between the three delivery mechanisms (a ranked list interface, a clustering interface, and an integrated interface with ranked list, clustering structure, and expert links) and two searching tasks (search for an individual document and a set of documents). They then conducted experiments with 24 subjects with three groups: Group 1 subjects were informed about the characteristics of each searching mechanism; Group 2 subjects were informed about the advantages of each search mechanism related to the type of tasks; and Group 3 subjects used two interfaces: the ranked list interface and the clustering interface. The researchers found no significant difference among the groups in terms of the number of documents read. Subjects from Group 3 used the least time when using ranked list interface, probably because they concentrated on one interface without distraction. Overall, search tasks did not affect the use of delivery mechanism, and searchers only used one delivery mechanism.

Approximately 5% to 15% of the patients (without ESRD) undergoing laparoscopic cholecystectomy require conversion to open cholecystectomy for various reasons [17]-[19]. Twelve patients with ESRD (26.7%) in this study required conversion to open cholecystectomy. The reason for conversion in 10 patients was related to intraabdominal adhesions that had consequently formed after recurrent episodes of peritonitis. The reason for conversion of the remaining two ESRD patients with hemodialysis was unable to display anatomy adequately in Calot’s triangle. In this study, history of peritonitis was the most important reason for changing the operative procedure to an open one. Duration of ESRD or CAPD did not affect the conversion rate but the number of pe- ritonitis episodes was important. In this study, converted cases had a history of at least 3 episodes of peritonitis. Roubicek et al. demonstrated that proinflammatory cytokines were increased in the visceral adipose tissue [20]. This may be another reason for dense adhesions that prevent LC. We have noted a significantly higher conver- sion rate in our case group but there is no CAPD history in Yeh’s study group [6].

One of the key features of our approach is the use of context-sensitive information such as the lan- guage model and reordering information. We show that the use of such a translation-benign search space is crucial to outperform state-of-the-art CLIR ap- proaches. Our experimental evaluation of retrieval performance is done on Wikipedia cross-lingual arti- cle retrieval (Bai et al., 2010; Schamoni et al., 2014) and patent prior art search (Fujii et al., 2009; Guo and Gomes, 2009; Sokolov et al., 2013; Schamoni et al., 2014). On both datasets, we show substan- tial improvements over the CLIR baselines of direct translation (Chin et al., 2008) or Probabilistic Struc- tured Queries (Ture et al., 2012b), with and with- out further parameter tuning using learning-to-rank techniques and extended feature sets. From our re- sults we conclude, that, in spite of algorithmic com- plexity, it is central to model translation and retrieval jointly to create more powerful CLIR models. 2 Related Work

C. Application of Content based Trademarks Retrieval With the rapid increase in the amount of registered trademark images around the world, trademark image retrieval (TIR) has emerged to ensure that new trademarks do not repeat any of the vast number of trademark images stored in the trademark registration system. As the traditional classification of trademark images is based on their shape features and types of object depicted by employing manually assigned codes, faults or slips may appear because of different subjective perception of the trademark images. Evidence has been provided that the traditional classification is not feasible in dealing with a large fraction of trademark images with little or no representational meanings.

The existence of the Private Information Retrieval problem is due to a fun- damental constraint of conventional querying. Namely, if one person, Tom, wants to query something from another person, Bob, then Tom must reveal the query content to Bob. For example, in a shop, the customer must tell the seller what he wants to buy. This fundamental constraint is so natu- ral and so freely accepted by human beings, that no one had ever thought of overcoming it until it recently actually became necessary. By overcoming the constraint, we mean solving a problem of querying without revealing the content of the query. A simplified version of this problem bears the name “Private Information Retrieval” problem (PIR), also alternatively called the “querying databases privately” problem within this book (Figure 1.1). Nu- merous motivating examples of applications that may benefit from a PIR solution will be presented in Section 1.3. In this section, let us concentrate on stating the problem.

Throughout this book, all relevant concepts and principles are systematically and lucidly explained, and the expositions are always accompanied by care- fully designed diagrams and illustrations. In any serious performance analysis, the use of mathematical modeling is unavoidable. The mathematics in the book are presented in a lucid style, and the notations adopted are natural, making the mathematical developments easy to understand and follow. Systems designers will find the wealth of techniques and analysis presented in the book an indispensable resource. Students of multimedia systems and advanced databases will find the treatment of topics and development of ideas in the book valuable to their understanding of efficient multimedia storage systems. Researchers of multimedia and database systems will find the book a vital source of reference. The unique and systematic coverage of topics in the book will make it an important and up-to-date resource for many types of readers.

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Computer do the indexing based on a CBIR scheme attempts to address the shortcomings of human-based indexing. Since a computer can process images at a much higher rate, while never tiring For example, each CBIR system needs to be tuned for its particular use in order to give optimal results. A retrieval system designed for querying medical x-ray images will more than likely prove to be a poor system for retrieving satellite images of South American rain forests. In addition, presently employed algorithms cannot yet consistently extract abstract features of images, such as emotional response, that would be relatively easy for a human to observe. Several approaches have been developed to capture the information of image contents by directly computing the image features from an image. The image features are directly constructed from the typical Block Truncation Coding or half toning based compressed data stream without performing the decoding procedure. These image retrieval schemes involve two phases, indexing and searching, to retrieve a set of similar images from the database. The indexing phase extracts the image features from all of the images in the database which is later stored in database as feature vector. In the searching phase, the retrieval system derives the image features from an image submitted by a user.

addition, presently employed algorithms cannot yet consistently extract abstract features of images, such as emotional response, that would be relatively easy for a human to observe. Several approaches have been developed to capture the information of image contents by directly computing the image features from an image. The image features are directly constructed from the typical Block Truncation Coding or half toning based compressed data stream without performing the decoding procedure. These image retrieval schemes involve two phases, indexing and searching, to retrieve a set of similar images from the database. The indexing phase extracts the image features from all of the images in the database which is later stored in database as feature vector. In the searching phase, the retrieval system derives the image features from an image submitted by a user.

There is evidence that preoperative starvation leads to decreased glycogen reserves and the induc- tion of postoperative insulin resistance. This resis- tance type is similar to untreated diabetes type 2. The output of energy during surgery is comparable to the energetic output during sport performance by sportsmen and it is well established that every sportsman renews his sugar reserves. It is possible to reduce postoperative insulin resistance with pre- operative oral or intravenous sugar administration [7–10]. Glucose application two hours before sur- gery leads to increased glycogen reserves, reduced stress reaction, reduced discomfort, and reduced exhaustion. It was shown in the past that 400 ml of clear fluid does not increase the risk of aspira- tion during intubation. The evacuation of clear fluid from the stomach takes less than 90 minutes [11, 12].