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The way Leibniz applied his philosophy to mathematics has been the subject of longstanding debates. A key piece of evidence is his letter to Masson on bodies. We offer an interpretation of this often misunderstood text, dealing with the status of infinite divisibility in nature , rather than in mathematics. In line with this distinction, we offer a reading of the fictionality of infinitesimals. The letter has been claimed to support a reading of infinitesimals according to which they are logical fictions, contradictory in their definition, and thus absolutely impossible. The advocates of such a reading have lumped infinitesimals with infinite wholes, which are rejected by Leibniz as contradicting the part–whole principle. Far from supporting this reading, the letter is arguably consistent with the view that infinitesimals, as inassignable quantities, are mentis fictiones , i.e., (well-founded) fictions usable in mathematics, but possibly contrary to the Leibnizian principle of the harmony of things and not necessarily idealizing anything in rerum natura. Unlike infinite wholes, infinitesimals—as well as imaginary roots and other well-founded fictions—may involve accidental (as opposed to absolute) impossibilities, in accordance with the Leibnizian theories of knowledge and modality. [ABSTRACT FROM AUTHOR]

Depuis 2012, les patients insuffisants rénaux chroniques de Nouvelle-Calédonie peuvent être inscrits sur une liste d'attente locale, et la transplantation rénale est réalisée en Australie. Ce programme a permis de diminuer le temps passé hors territoire pour une greffe rénale et de réduire la charge économique d'une greffe rénale pour la Nouvelle-Calédonie. Nous avons réalisé un état des lieux afin d'avoir un regard objectif sur la situation actuelle. L'objectif principal était de décrire l'accès à la liste d'attente pour les patients en dialyse péritonéale, et dans un second temps, de comparer les patients ayant un parcours à l'accès à la greffe conforme aux recommandations de la Haute Autorité de santé versus non conforme. Tous les patients en dialyse péritonéale au 31 juillet 2018 ont été inclus. Un questionnaire standardisé a été rempli par deux néphrologues, en s'appuyant sur le dossier médical informatisé et partagé du patient. Le parcours d'accès à la liste d'attente de greffe était considéré conforme si le patient était inscrit sur liste d'attente ou s'il avait une contre-indication à la greffe, ou encore si un bilan pré-transplantation datait de moins de 6 mois. Le parcours était considéré non conforme si le patient avait commencé un bilan depuis plus de 6 mois ou n'avait pas commencé son bilan. Au total, 61 patients de Nouvelle-Calédonie et Wallis et Futuna suivis en dialyse péritonéale ont été inclus. Ils étaient âgés en moyenne de 62 ans. La durée moyenne depuis la prise en charge de l'insuffisance rénale chronique était de 6,7 ans et depuis la mise en dialyse de 2,0 ans. Parmi eux, 11 (18 %) étaient inscrits sur liste d'attente, 26 (43 %) avaient au moins un motif contre-indiquant la greffe rénale, 3 (5 %) avaient commencé un bilan depuis moins de 6 mois et 21 (34 %) avaient un bilan qui durait depuis plus de 6 mois ou n'avaient pas commencé leur bilan. Parmi ces 21 patients avec un parcours non conforme, les 3 raisons le plus fréquemment identifiées étaient une programmation du bilan défectueuse (67 % ; n = 14), un éloignement géographique (48 % ; n = 10) et un événement de santé intercurrent (29 % ; n = 6). Parmi les patients résidant dans le Grand Nouméa, 74 % avaient un bilan conforme contre 44 % pour les patients résidant hors le Grand Nouméa (p = 0,058). Près d'un patient sur deux non inscrit sur liste d'attente n'a pas eu d'information sur la greffe rénale ou l'information n'a pas été tracée dans le dossier médical informatisé. Cette étude a mis en évidence 2 facteurs principaux d'une évaluation non conforme à la transplantation rénale : habiter en dehors du Grand Nouméa et une programmation de bilan défectueuse. Il apparaît également un manque d'information au patient. Ces facteurs de risque d'inscription tardive et de non-inscription sont à prendre en compte par les équipes soignantes. Cet état des lieux permettra d'avoir un point de référence pour évaluer l'impact des actions d'amélioration d'accès à la transplantation rénale déployées en Nouvelle-Calédonie. Since 2012, a deceased donor kidney transplant program exists for dialysis patients living in New-Caledonia in collaboration with Royal Prince Alfred Hospital in Sydney, Australia. This program has reduced the time spent out-of-territory for a renal transplantation and has reduced the economic burden of end stage renal disease in New-Caledonia. We have realised a photography of kidney transplants evaluation for patients in peritoneal dialysis in New-Caledonia and Wallis and Futuna. The first aim was to describe access to kidney transplants evaluation for dialysis patients. A second aim was to compare patients with a conformed kidney transplant evaluation and patients without transplant evaluation with no obvious reasons identified. All patients in peritoneal dialysis in New-Caledonia and Wallis and Futuna at the 2018, 31st july were included. A standardised form was filled by two nephrologists. The computerised shared medical record was used to collect information. A kidney transplant evaluation was adequate for patients registered on transplant waiting list, patients with medical contraindications identified or patients with evaluation exams begun less than 6 months. In total, 61 patients were included. The average age was 62 years old. The chronic kidney disease care average time was 6.7 years and the dialysis average time was 2.0 years. Among them, 11 (18 %) were registered on the waiting list, 26 (43 %) had at least one kidney transplant medical contraindication, 3 (5 %) had begun transplant exam since less than 6 months and 21 (34 %) had no transplant exam begun or transplant exam begun since more than 6 months without medical contraindication identified. Among those 21 patients, the three most common reasons were a faulty programming transplant exam (67 %; n = 14), a remote living place (48 %; n = 10) and an intercurrent health event (29 %; n = 6). Among patients living in Noumea and suburbs, 74 % had a conformed transplant evaluation against 44 % in patients living outside Noumea and suburbs (P = 0.058). Nearly one in two patients not on the waiting list had have no information about kidney graft or the information was not recorded in the medical record. This study showed two main factors of a non-conformed transplantation evaluation: living outside Noumea and suburbs and a non-efficient planning of pre-transplant assessment exams. There is also a lack of information to the patient. These risk factors for late registration and non-registration must be considered by the healthcare teams. This study will provide a point of reference to assess the impact of actions to improve access to renal transplantation deployed in New-Caledonia. [ABSTRACT FROM AUTHOR]

The present study examines the burial customs of the late Iron Age in southwestern Switzerland. Two necropolises in the Valais region are being investigated from a multidisciplinary perspective in order to improve the socio-cultural understanding of this period. The results indicate a regional particularism in the burial rites of the late Iron Age in southwestern Switzerland, but also show cultural influences from neighboring regions. The study provides insights into the functioning of Celtic communities in this region. [Extracted from the article]

The problem of the rectification of curves and the calculation (for which we shall adopt the more geometric term "flattening") of the surface of a rotating solid generated by a curve, once the rotation axis has been fixed, were treated by John Wallis in two short inter-related tracts on cycloids and cissoids in 1659. In this work, we focus on the problem of the rectification of the parabola, an ancient problem reproposed in the 17th century, and on the solution obtained by Wallis using particular series that reflect the mechanical method of Archimedes, even if this is not immediately apparent to the reader. In presenting Wallis's speech, we use the language closest to us and make explicit all the calculations not performed by the author, favoring an understanding of the part of his writing dedicated to the rectification of the parabola. [ABSTRACT FROM AUTHOR]

This article proposes a possible path devoted to upper secondary school and early university students, as well as training teachers, with the aim to build a conscious approach to the learning/teaching of the conics, which uses, for an educational purpose, the close relationship between conics as loci of points of a plane and conics as sections of a cone. In this path, we will refer to some elements taken from the history of mathematics relating to a particular conic: the parabola. These elements could help students to discover and realize the transition from a parabola considered as a curve in a plane to the same parabola considered on a cone of which it is a section, as well as the inverse passage, and to grasp the profound link between two presentations of the same geometric object. Both steps will be carried out through constructions made with the use of the GeoGebra dynamic geometry software. In addition, it will be highlighted how the construction of conics by points has allowed the creation of lenses and mirrors, which represents a practical application of geometry very relevant to physics and astronomy. Such a practical approach could help students to overcome the difficulty in understanding conics by making the argument less abstract. Moreover, this path could build up an environment in which teachers and students could explore some semiotic registers and their changes, through which Mathematics expresses itself. In the final part, an educational experiment of the path that was proposed will be shown to the students of the Master's degree course of "mathematics education" at the Department of Mathematics and Computer Science of the University of Calabria. The results of this experiment are described in detail and seem to confirm that the twofold view of the parabola as a section of a cone and as locus of points of a plane helps the students in understanding its meaning in both theoretical and applicative fields. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Wallis interspinous dynamic stabilization system has been used in China for more than 10 years, but its long-term survivorship and reoperation rate are rarely reported. OBJECTIVE: To observe the long-term efficacy, complication rate, reoperation rate and survival rate of Wallis interspinous process dynamic stabilization system in the treatment of lumbar degenerative disc disease. METHODS: 126 patients with lumbar disc degenerative disease who underwent posterior decompression or discectomy + Wallis fixation in Guangdong Provincial People’s Hospital from May 2008 to March 2013 followed up for more than 7 years were retrospectively selected. Indications, preoperative and postoperative Japanese Orthopedic Association, Oswestry disability index, visual analogue scale score, complications, reoperation, and device survival rate were evaluated. RESULTS AND CONCLUSION: (1) A total of 103 cases completed follow-up, with a mean value of (124.43±11.44) months. Of 103 patients, 9 cases were diagnosed as lumbar stenosis, 46 cases as lumbar disc herniation, 41 cases as lumbar stenosis combined with lumbar disc herniation, and 7 cases as spondylolisthesis. (2) Japanese Orthopedic Association, Oswestry disability index, visual analogue scale scores at last follow-up were better than those before surgery (P < 0.05). (3) Overall complication rate was 14.5% (15/103), including prosthesis burst, spinous process fracture, recurrence of surgical or adjacent disc herniation, wound infection and recurrent low back pain. The reoperation rate was 7.8% (8/103). (4) The 5-year and 10-year survival rates were 98.1% (101/103) and 97.1% (100/103). (5) Compared with patients with other diseases, patients with lumbar disc herniation had the highest rate of complication (21.7%, 10/46) and reoperation rate (13%, 6/46), and the lowest 5-year 95.7% (44/46) and 10-year 93.5% (43/46) survival rates. (6) Wallis implantation can achieve satisfactory long-term survival rate and clinical outcomes in the treatment of lumbar disc degenerative diseases. However, complication rate and reoperation rate in patients with lumbar disc herniation are higher, and the survival rate is lower. Thus, Wallis implant should be used cautiously in patients with this diagnosis. [ABSTRACT FROM AUTHOR]

The problem of the rectification of curves and the calculation (for which we shall adopt the more geometric term “flattening”) of the surface of a rotating solid generated by a curve, once the rotation axis has been fixed, were treated by John Wallis in two short inter-related tracts on cycloids and cissoids in 1659. In this work, we focus on the problem of the rectification of the parabola, an ancient problem reproposed in the 17th century, and on the solution obtained by Wallis using particular series that reflect the mechanical method of Archimedes, even if this is not immediately apparent to the reader. In presenting Wallis’s speech, we use the language closest to us and make explicit all the calculations not performed by the author, favoring an understanding of the part of his writing dedicated to the rectification of the parabola.

Copyright of Tópicos is the property of Asociacion Revista de Filosofia de Santa Fe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)