Delamination effect on the mechanical behavior of 3D printed polymers

 This study aims to assess the delamination effect and predict the evolution of damage in 3D printed specimens to investigate the mechanical behavior occurring due to the delamination of the layers of 3D printed thermoplastic polymers. Thus, additively manufactured ABS samples are subjected to tensile tests Made for different thicknesses of specimens by subtracting layer by layer. The mechanical behavior of the layers and the adherence between the layers are studied in this paper. The deposition of the layers is modeled as a laminated material. The delamination effect on the resistance of printed material is evaluated experimentally by comparing the mechanical characteristics of homogenously printed specimens, and laminated layers gathered together. Thus, the global resistance is reduced significantly due to the lack of adherence. Besides, crack growth, and critical intensity factor investigation are based on damage and rupture mechanics theories. Furthermore, the results allowed us to evaluate the energy behavior of the 3D printed material subjected to static loads and subsequently predict the evolution of the damage and find out the impact of layers' delamination. Indeed, we determined three stages of damage along with the critical life fraction leading to the failure of the specimen

Dural tear of unusual cause

Epidural analgesia is highly recommended in cancer anorectal surgery. In addition to the fight against pain it provides some benefit in allowing early rehabilitation of patients. One of the risks of this practice is the dural tear creating a cerebrospinal fluid leak (CSF) in the epidural space (EPD). Clinical features the typical positional headache, a procession of various more or less severe symptoms: nausea, vomiting, dizziness, visual or hearing impairment or radicular pain. We report a dural of unusual cause secondary of the  obstruction of tuohy catheter by vertebral cartilage

XMCD studies and magnetic properties of ZnTe doped with Ti, Cr, Mn and Co

Using the full potential linear augmented plane wave (FP-LAPW) method as implemented in the WIEN2K code in connection with the Generalized Gradient Approximation (GGA). We study the magnetic properties of ZnTe doped with some transition metals elements. In addition, to the X-ray absorption spectra (XAS) and X-ray Magnetic circular dichroism (XMCD) calculations to compute the orbital and spin moments separately. Two principal examples will be given: The induced magnetic moments ZnTe of the light and heavy 3d elements (Ti, Cr and Mn, Co) can be determined by the XMCD sum rules analysis at the L2,3 edges. Moreover, it has been found that for the lighter 3d elements the spin-orbit splitting of the transitions 2P1/2 and 2P3/2 states reduces toward, which has a consequence that two excitations are coupled

Delamination effect on the mechanical behavior of 3D printed polymers

This study aims to assess the delamination effect and predict the evolution of damage in 3D printed specimens to investigate the mechanical behavior occurring due to the delamination of the layers of 3D printed thermoplastic polymers. Thus, additively manufactured ABS samples are subjected to tensile tests made for different thicknesses of specimens by subtracting layer by layer. The mechanical behavior of the layers and the adherence between the layers are studied in this paper. The deposition of the layers is modeled as a laminated material. The delamination effect on the resistance of printed material is evaluated experimentally by comparing the mechanical characteristics of homogenously printed specimens, and laminated layers gathered together. Thus, the global resistance is reduced significantly due to the lack of adherence. Besides, crack growth, and critical intensity factor investigation are based on damage and rupture mechanics theories. Furthermore, the results allowed us to evaluate the energy behavior of the 3D printed material subjected to static loads and subsequently predict the evolution of the damage and find out the impact of layers delamination. Indeed, we determined three stages of damage along with the critical life fraction leading to the failure of the specimen

Abord trans-symphysaire des ruptures posttramatiques de l’urètre postérieur chez l’adulte

Objectif: Etudier la place de la voie trans-symphysaire dans le traitement des ruptures posttraumatiques de l’urètre postérieur vues tardivement et en évaluer ses résultats. Patients et méthodes: Cinq malades ayant une rupture complète post-traumatique de l’urètre postérieur (> 2,5 cm et/ou échec d’un traitement antérieur) ont été traités dans notre service au stade de sténose urétrale. Tous les patients ont eu une urétrorraphie termino-terminale par voie trans-symphysaire seule. Une description technique et une évaluation clinique et paraclinique des résultats sur le plan mictionnel et sexuel ont été réalisées dans ce travail. Résultats: Les résultats ont été évalués avec un suivi médian de 19 mois. Aucune complication post-opératoire immédiate (saignement, fistule, douleur) n’a été rapportée. Sur le plan mictionnel, on a constaté dans tous les cas une miction satisfaisante, sans troubles de la continence et un cas de dysfonction érectile améliorée par le traitement médical. Aucun patient ne s’est plaint de troubles de la statique pelvienne. Conclusion: La voie trans-symphysaire constitue un excellent abord pour le traitement des lésions complexes de l’urètre postérieur vues tardivement. Cette technique permet d’avoir un abord direct sur l’urètre postérieur et de réaliser une suture termino-terminale sans tension. Les résultats sont satisfaisants et les inconvénients sont plus théoriques que réels.Mots clés : Rupture de l’urètre postérieur, sténose de l’urètre postérieur, urétrorraphie, voie transsymphysair

Reproductive performance of native and imported dairy cows in the Tadla region (Morocco)

Parmi les performances de reproduction des vaches laitières dans la région du Tadla (Maroc) sur une période de 4 années, l’âge à la première insémination artificielle (IA) a été de 573,4 ± 35,6 jours et à l’âge au premier vêlage de 853,8 ± 103,5 jours, l’intervalle vêlage-1ère IA de 75,5 ± 35,6 jours. Celui-ci a été plus court chez les femelles importées que chez les natives. La race Montbéliarde a été inséminée plus tôt que la race Prim’Holstein. Le taux de réussite en 1ère IA a été de 53,2% avec de larges variations inter-annuelles et inter-élevages. Les Prim’holstein ont été mieux fécondées que les autres races. 18,2% des vaches ont nécessité 3 IA ou plus et l’indice coïtal a été de 1,8 ±1,3. La campagne, l’élevage et la race ont affecté significativement le taux de femelles ayant nécessité 3 IA ou plus. La race Prim’holstein française a manifesté un taux inférieur à celui de la race Prim’holstein canadienne. L’intervalle vêlage - insémination fécondante a été de 119,2 ± 83,8 jours. Ce paramètre a varié très significativement selon l’année, l’élevage, la race et le numéro de lactation. La race Montbéliarde a présenté undélai moyen de fécondation plus court que la race Prim’Holstein Canadienne

Emplacement of inflated Pāhoehoe flows in the Naude’s Nek Pass, Lesotho remnant, Karoo continental flood basalt province: use of flow-lobe tumuli in understanding flood basalt emplacement

Physical volcanological features are presented for a 710-m-thick section, of the Naude’s Nek Pass, within the lower part of the Lesotho remnant of the Karoo Large Igneous Province. The section consists of inflated pāhoehoe lava with thin, impersistent sedimentary interbeds towards the base. There are seven discreet packages of compound and hummocky pāhoehoe lobes containing flow-lobe tumuli, making up approximately 50% of the section. Approximately 45% of the sequence consists of 14 sheet lobes, between 10 and 52-m-thick. The majority of the sheet lobes are in two packages indicating prolonged periods of lava supply capable of producing thick sheet lobes. The other sheet lobes are as individual lobes or pairs, within compound flows, suggesting brief increases in lava supply rate. We suggest, contrary to current belief, that there is no evidence that compound flows are proximal to source and sheet lobes (simple flows) are distal to source and we propose that the presence of flow-lobe tumuli in compound flows could be an indicator that a flow is distal to source. We use detailed, previously published, studies of the Thakurvadi Formation (Deccan Traps) as an example. We show that the length of a lobe and therefore the sections that are ‘medial or distal to source’ are specific to each individual lobe and are dependent on the lava supply of each eruptive event, and as such flow lobe tumuli can be used as an indicator of relative distance from source

Observation of a maternal transmission of scrapie in sheep

A pregnant ewe with suspected scrapie was referred to the Regional Veterinary Laboratory in Limoges on 11 January 2002, in compliance with the French scrapie eradication program. Western Blot confirmed the diagnosis of scrapie. Ten days later, the ewe gave birth. As we had to help the ewe, we were able to isolate the ewe lamb before she had any contact with her mother, and especially no colostrum. The ewe lamb was fed with milk replacers and isolated to prevent all possibility of horizontal transmission of scrapie. In August 2002, the first symptoms of scrapie appeared in the ewe lamb. Euthanasia was decided on 18 December 2002, as the animal was no longer able to stand. Western Blot and immunohistochemistry tests confirmed natural scrapie in the ewe lamb. PrP genotyping of this lamb was ARQ/VRQ. This first confirmed case of maternal transmission of scrapie in sheep is associated with a particularly short incubation time (6 months) in natural conditions.Dans le cadre du programme d'éradication de la tremblante en France, nous avons reçu une brebis gestante suspecte de tremblante le 11 janvier 2002, au laboratoire vétérinaire départemental de Limoges (confirmée ultérieurement par un Western Blot). Dix jours plus tard, la brebis agnela avec difficulté et nous avons dû intervenir pour l'aider. Cette assistance à l'agnelage nous permit d'isoler immédiatement le nouveau-né, en évitant tout contact ultérieur avec sa mère, en particulier sans la possibilité d'absorber le colostrum. L'agnelle fut placée dans un endroit isolé sans qu'il n'y ait de possibilité de transmission horizontale de la tremblante et fut nourrie avec des lactoremplaceurs. En août 2002, les premiers symptômes de la tremblante sont apparus chez l'agnelle née de cette brebis. Du fait d'une évolution vers le décubitus, l'euthanasie de l'agnelle fut décidée le 18 décembre 2002. La confirmation d'une tremblante naturelle chez l'agnelle a été obtenue par le Western-Blot et les examens immunohistochimiques. Le génotype de l'agnelle était ARQ/VRQ. Cette première confirmation d'une transmission maternelle de la tremblante chez le mouton s'accompagne aussi d'un temps d'incubation particulièrement court (6 mois) dans les conditions naturelles

Pre-hospital management protocols and perceived difficulty in diagnosing acute heart failure

Aim To illustrate the pre-hospital management arsenals and protocols in different EMS units, and to estimate the perceived difficulty of diagnosing suspected acute heart failure (AHF) compared with other common pre-hospital conditions. Methods and results A multinational survey included 104 emergency medical service (EMS) regions from 18 countries. Diagnostic and therapeutic arsenals related to AHF management were reported for each type of EMS unit. The prevalence and contents of management protocols for common medical conditions treated pre-hospitally was collected. The perceived difficulty of diagnosing AHF and other medical conditions by emergency medical dispatchers and EMS personnel was interrogated. Ultrasound devices and point-of-care testing were available in advanced life support and helicopter EMS units in fewer than 25% of EMS regions. AHF protocols were present in 80.8% of regions. Protocols for ST-elevation myocardial infarction, chest pain, and dyspnoea were present in 95.2, 80.8, and 76.0% of EMS regions, respectively. Protocolized diagnostic actions for AHF management included 12-lead electrocardiogram (92.1% of regions), ultrasound examination (16.0%), and point-of-care testings for troponin and BNP (6.0 and 3.5%). Therapeutic actions included supplementary oxygen (93.2%), non-invasive ventilation (80.7%), intravenous furosemide, opiates, nitroglycerine (69.0, 68.6, and 57.0%), and intubation 71.5%. Diagnosing suspected AHF was considered easy to moderate by EMS personnel and moderate to difficult by emergency medical dispatchers (without significant differences between de novo and decompensated heart failure). In both settings, diagnosis of suspected AHF was considered easier than pulmonary embolism and more difficult than ST-elevation myocardial infarction, asthma, and stroke. Conclusions The prevalence of AHF protocols is rather high but the contents seem to vary. Difficulty of diagnosing suspected AHF seems to be moderate compared with other pre-hospital conditions