Sensor fusion-based localization methods for mobile robots : a case study for wheeled robots

Localization aims to provide the best estimate of the robot pose. It is a crucial algorithm in every robotics application, since its output directly determines the inputs of the robot to be controlled in its configuration space. In real world of engineering, the robot dynamics related measurements are subject to both uncertainties and disturbances. These error sources yield unreliable inferences of the robot state, which inherently result in wrong consensus about the appropriate control strategy to be applied. This outcome may drive the system out of stability and damage both the physical system and its environment. The localization algorithm captures the uncertainties with probabilistic approaches. Namely, the measurement processes are modelled along with their unreliability, moreover, the synergy of multiple information sources is formulated with the aim to calculate the most probable estimate of the robot pose. In essence, this algorithm is composed of two main parts, i.e., first the dynamics of the system is derived, and the corresponding uncertainties are initially predicted, next the additional sensor information is incorporated in the algorithm to refine the posterior estimate. This approach provides the state-of-the-art solution for the derivation of mobile robot poses in real applications

Sensor fusion-based localization methods for mobile robots: A case study for wheeled robots

Localization aims to provide the best estimate of the robot pose. It is a crucial algorithm in every robotics application, since its output directly determines the inputs of the robot to be controlled in its configuration space. In real world of engineering, the robot dynamics related measurements are subject to both uncertainties and disturbances. These error sources yield unreliable inferences of the robot state, which inherently result in wrong consensus about the appropriate control strategy to be applied. This outcome may drive the system out of stability and damage both the physical system and its environment. The localization algorithm captures the uncertainties with probabilistic approaches. Namely, the measurement processes are modelled along with their unreliability, moreover, the synergy of multiple information sources is formulated with the aim to calculate the most probable estimate of the robot pose. In essence, this algorithm is composed of two main parts, i.e., first the dynamics of the system is derived, and the corresponding uncertainties are initially predicted, next the additional sensor information is incorporated in the algorithm to refine the posterior estimate. This approach provides the state-of-the-art solution for the derivation of mobile robot poses in real applications

Lesioni non palpabili della mammella: la Mammotome-biopsy nella gestione preoperatoria del cancro della mammella

Premessa: Il tumore del seno è nei paesi occidentali al primo posto per frequenza nelle donne e la sua incidenza è in costante crescita. Grazie soprattutto alla diffusione dello screening mammografico e ad una maggiore consapevolezza del problema, negli ultimi anni è aumentata la diagnosi delle cosiddette lesioni “non palpabili”; parimenti si è assistito ad un importante sviluppo delle metodiche diagnostiche di tipo mininvasivo. Alla tradizionale citologia con ago sottile si sono affiancate infatti varie procedure bioptiche percutanee; tali metodiche microistologiche hanno quasi del tutto sostituito la biopsia chirurgica escissionale e l’esame intra-operatorio al congelatore. Pazienti e metodo: Nella nostra Divisione di Chirurgia Generale, Vascolare e Mininvasiva, dal dicembre 1999 al settembre 2004 abbiamo eseguito, in collaborazione con il servizio di Radiologia, 214 biopsie su guida ecografia utilizzando la vacuum-assisted biopsy (Mammotome® ) con ago 11-Gauge. I risultati ottenuti per ciò che concerne l’accuratezza diagnostica, la quantità e qualità delle informazioni ottenute, il significato delle stesse nella eventuale gestione chirurgica, il discomfort globale per la paziente sono stati analizzati e discussi nel presente lavoro. Risultati: Delle 214 biopsie eseguite con tecnica Mammotome, nell’89,3% dei casi si è trattato di lesioni clinicamente non palpabili, con un diametro medio di 8 mm. L’età media delle pazienti era di 57,6 anni (range 31-88). La positività per patologia maligna è stata di 90 casi (42%). Nei casi di iperplasia duttale atipica e radial scar (6%) è stata effettuata l’exeresi chirurgica della lesione che ha confermato nel 100% dei casi la precedente diagnosi bioptica. Il 19% delle pazienti sottoposte a biopsia Mammotome era stato precedentemente sottoposto ad un prelievo citologico con ago sottile. Confrontando i risultati delle due metodiche, l’attendibilità diagnostica della seconda risulta essere significativamente superiore (p<0,05) come pure il numero di informazioni ottenute (istotipo, invasività, grading, recettori ormonali, etc.); il discomfort legato alla procedura, valutato in termini di dolore (VAS), è risultato inferiore a quello del prelievo con ago sottile (p<0,05). L’unica complicanza della biopsia Mammotome è rappresentata dall’ematoma nella sede del prelievo (8% dei casi). Il numero dei falsi negativi è stato di un caso, dovuto ad un non corretto centraggio del bersaglio. Conclusioni: Allo stato attuale in presenza di una lesione non palpabile della mammella la scelta della metodica diagnostica (agobiopsia o Mammotome) è legata al sospetto radiologico nella prospettiva di un eventuale intervento chirurgico. La biopsia con Mammotome nelle lesioni non palpabil

Riparazione laparoscopica dei laparoceli e delle ernie ombelicali. Nostra esperienza

Introduzione - Il laparocele rappresenta una complicanza frequente dopo una laparotomia (2-20%). Il tasso di recidive dopo una riparazione semplice non protesica è ancora maggiore. L’utilizzo delle protesi ha comportato una riduzione delle recidive. Nell’ultimo decennio, la riparazione laparoscopica dei laparoceli e delle ernie ombelicali è divenuta una interessante alternativa alla procedura open. Pazienti - Scopo di questo studio retrospettivo è quello di valutare l’efficacia, la sicurezza ed i vantaggi dell’approccio laparoscopico relativamente al trattamento laparoscopico dei laparoceli e delle ernie ombelicali. Dal febbraio 2000 al giugno 2006, complessivamente 127 laparoceli (primari e recidivi), 21 ernie ombelicali e 19 ernie epigastriche sono state trattate con approccio mininvasivo. I criteri di esclusione sono stati: dimensioni del difetto inferiore a 2 cm o superiore a 20 cm, problematiche anestesiologiche, disordini emo-coagulativi. Il rapporto femmine/maschi è stato di 0.7, l’età media di 59 anni (24-83). Le patologie addominali associate, trattate contemporaneamente, sono state 26. Tre casi sono stati operati in condizioni di urgenza (laparoceli strozzati). Risultati - Il tasso di conversione in chirurgia open è stato di 2 casi (1.2%). Il tempo operatorio medio di 78 minuti (25-170) e la degenza media post-operatoria di 2.1 giorni (1-5). Le complicanze intra- e post-operatorie sono state del 5% (soprattutto sieromi), le recidive osservate 1.8% (3 casi). Conclusioni - Ulteriori studi con follow-up adeguati sono necessari per poter dimostrare i reali vantaggi della tecnica laparoscopica, tuttavia l’esperienza riportata di oltre 5 anni dimostra che in casi selezionati l’approccio laparoscopico può rappresentare un’ interessante ed efficace alternativa alla tecnica open

[Laparoscopic repair of incisional and umbilical hernias. Our experience]

Background - Incisional hernia is a frequent complication of abdominal surgery (2-20% of all cases). Recurrence rate after simple repair without mesh is very high. The use of prosthetic materials has reduced the recurrences. Over the past decade, laparoscopic repair of incisional and umbilical hernias has become an interesting alternative to open procedure. Patients and methods - The aim of this retrospective study was to evaluate efficacy, safety and advantages of laparoscopic approach in the treatment of incisional and umbilical hernias. From February 2000 through June 2006, a total of 127 incisional hernias (primary and recurrent), 21 umbilical and 19 epigastric hernias, were treated by laparoscopic approach. The exclusions for laparoscopy were: defect size less than 2 cm or more 20 cm, anesthesiologic problems, hemocoagulative disorders. The females/males ratio was 0/7, with a mean age of 59 years (range 24-83). The abdominal associated disease treated were 26. Three cases were treated as urgencies (strangulated hernias). Results - The conversion rate was 2 cases (1.2%). Mean operative time was 78 min (range 25-170). The mean postoperative hospital stay was 2.1 days (range: 1-5). The intra- and postoperative complication rate was 5% (above all seromas). The recurrence rate was 1.8% (3 cases). Conclusions - More studies with long-term follow-up are necessary to prove the advantages of laparoscopic technique, but this large experience of more than 5 years, demonstrates that in selected cases the laparoscopic approach may be an interesting and effective alternative to open technique

[Non palpable lesions of the breast: the Mammotome-biopsy in the preoperative management of breast cancer].

BACKGROUND: Breast tumour takes first place for frequency in women in Western Countries and is in constant increase. The diagnosis of the so-called non palpable lesions is increased remarkably above all due to the diffusion of mammographic screening and to a greater awareness of the problem. Furthermore it is helped by an important development of mininvasive diagnostic methods: the traditonal cytology with fine needle is supported by various trans-skin bioptic procedures (micro-histological examination). This methods almost always replaces the surgical excisional biopsy and frozen intraoperative examination, still used but reserved for particular cases. PATIENTS AND METHODS: In our Department of General and Mininvasive Surgery, from December 1999 to September 2004, we carried out 214 biopsies, with the collaboration of the radiological Service, under echographic guidance using vacuum--assisted biopsy (Mammotome) with 11-Gauge needle. The results are examined and discussed here in this report with regard to diagnostic accuracy, quantity and quality of information, significant for subsequent surgical management. RESULTS: Of 214 biopsies carried out with Mammotome technique, 89.3% of the cases are clinically non palpable lesions, with a average diameter of 8 mm. The average age of patients was 57.6 years (range 31-88). There are 90 cases of positive malignant pathology (42%). In the atypical ductal iperplasia and radial scar cases (6%) surgical removal of lesion was carried out which confirmed the previous bioptic diagnosis in 100% of cases. The 19% of patients submitted to a Mammotome biopsy was subject previously to cytology with fine needle. Comparing the results of both methods the diagnostic reliability of Mammotome was significantly superior (p < 0.05) as also the amount of information obtained (histotype, invasivity, grading, estrogen receptor, etc.); discomfort linked to the procedure, valued as pain (VAS), resulted inferior to the discomfort of biopsy with fine needle. The only complication of Mammotome biopsy is represented by haematoma in the biopsy site (8% of cases). The number of false negatives was one case due to incorrect targeting. CONCLUSION: In the present situation, the choice of method is conditioned by the degree of radiological suspicion, taking into account the information obtained thereby, in order to ensure the appropriate surgise management. Mammotome biopsy of non palpable lesions of the breast, in our experience, is preferable if suspicion of malignancy is high. In this way a correct preoperative strategy can be prepared. Including the sentinel lymphnode method. Consequently a decision regarding the type of surgery can be taken (generally conservative), as well as making easier the intraoperative localisation of lesion by positioning the metallic clips during biopsy

Buena Vida, Buen Vivir : imaginarios alternativos para el bien común de la humanidad

La obra reúne planteamientos tanto teóricos como empíricos desarrollados por colegas de reconocida trayectoria sobre la situación actual, los desafíos, las contradicciones o imaginarios alternativos para el bien común de la humanidad. Se ha puesto especial atención a propuestas relativas al denominado Buen Vivir o Vivir Bien, y a otras similares que rebasan las realidades andinas como las visualizadas en y desde México y desde otros países de Iberoamérica. Los análisis abordan diversas temáticas como la gestión de los recursos naturales, la producción de alimentos y las actividades extractivas, hasta cuestiones de cambio climático, ecología y género

Comparing fibrin sealant with staples for mesh fixation in laparoscopic transabdominal hernia repair: A case control-study

Background: Laparoscopic hernia repair is not as popular as cholecystectomy. We have performed more than 3,000 laparoscopic herniorrhaphies using the trans-abdominal (TAPP) technique. To prevent recurrences we fix the polypropylene mesh with staples. The use of fibrin glue for graft fixation is a possible alternative. Methods: We have performed 3,130 laparoscopic hernia repairs over 14 years. For mesh fixation we used titanium clips and observed a small number of complications. In July 2003 we started using fibrin glue (Tissucol®). The purpose of this retrospective longitudinal study was to evaluate if the use of fibrin sealant was as safe and effective as conventional stapling and if there were differences in post-operative pain, complications and recurrences. Results: From July 2003 to June 2006 we performed 823 laparoscopic herniorrhaphies. Fibrin glue (Tissucol®) was used in 88 cases. Two homogeneous groups of 68 patients (83 cases) treated with fibrin glue and 68 patients (87 cases) where the mesh was fixed with staples, were compared. Patients with relevant associated diseases or large inguino-scrotal hernias were excluded. Operative times were longer in the group treated with fibrin glue with a mean of 35 minutes (range 22-65 mins) compared to the group treated with staples (25 minutes, range 14-50 mins). The time of hospital stay was the same (24 hours). Post-operative complications, that were more frequent in the stapled group, included trocar site pain, hematomas, intra-operative bleedings and incisional hernias. No significant difference was observed concerning seromas, chronic pain and recurrence rate. Conclusions: Less post-operative pain, and a faster return to usual activities are the main advantages of laparoscopic repair compared to the traditional approach. The use of fibrin sealant reduces in our experience the risk of post- and intra-operative complications such as bleeding and incisional hernia; recurrence rates are similar, but the operative time is longer. © 2007 Springer Science+Business Media, LLC