70 research outputs found

    Computational angular oscillatory motion for a .50 caliber bullet type firing from a helicopter machine gun

    Get PDF
    Abstract The present study investigates the epicyclic pitching and yawing motion phenomenon of spinning symmetric projectiles applying the 6-DOF free flight dynamic simulation modelling for small-yaw flat-fire trajectories. The computational results are compared with the corresponding classical second order linear differential solution. The ammunition will be used is the .50 API M8 bullet tfiring from M2 machine gun launched horizontally from different firing angles on high-speed subsonic aircraft (helicopter). This analysis includes mean constant coefficients of the most significant aerodynamic forces, moments and Magnus effects, which have been taken from official tabulated database

    Compound and acutely ruptured false aneurysm of the brachial artery: a case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>A patient with a neglected, compound acutely ruptured false aneurysm of the brachial artery which developed after a periprosthetic fracture of the right humerus, is reported.</p> <p>Case presentation</p> <p>An 84-year-old Greek woman underwent right shoulder hemiarthroplasty 2 years before a periprosthetic fracture which was treated conservatively in another hospital. After removing the U-slab herself, she noticed the development of an ulcer on the mid-humerus, with continuous oozing but no fever. This led to above-elbow amputation in an attempt to save the patient's life.</p> <p>Conclusion</p> <p>It is hoped that by awareness of such a possibility coupled with an early diagnosis based on the clinical picture and imaging modalities, such unfortunate results can be avoided in the future. In case of increasing displacement at the fracture site and excessive local swelling, the possibility of the presence of a false brachial aneurysm should be ruled out despite the presence of normal perfusion of the hand and palpable radial and ulnar pulses.</p

    Genotyping the phenotypic diversity in Aegean Natrix natrix moreotica (Bedriaga, 1882) (Reptilia, Serpentes, Natricidae)

    Get PDF
    We examined the mitochondrial identity of Aegean Natrix natrix moreotica representing different morphotypes, with a focus on new material from Milos and Skyros. We found no correlation between distinct morphotypes and mitochondrial identity. Our results support that grass snake populations are polyphenetic and that southern subspecies, including island populations, show a higher variability than northern ones

    Sciatica due to extrapelvic heterotopic ossification: A case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>Sciatica is a common problem, usually caused by disc herniation or spinal stenosis. Low back pain is also present in most cases. When sciatica is the unique clinical finding, especially in young patients, extraspinal pathology should be investigated.</p> <p>Case presentation</p> <p>We describe a rare case of sciatica in a 32-year-old man, which was developed as a complication of post-traumatic pelvic heterotopic ossification. During the operation, the sciatic nerve was found to be bluish, distorted and compressed in an hourglass fashion around a heterotopic bone mass. The heterotopic bone tissue, 4 cm in diameter, was removed and the patient had fully recovered 3 months after the operation.</p> <p>Conclusion</p> <p>In cases of sciatica without back pain, the possibility of direct pressure of the sciatic nerve from cysts, tumours or bone, as in the present case, should be considered.</p

    On-chip integrated graphene aptasensor with portable readout for fast and label-free COVID-19 detection in virus transport medium

    Get PDF
    Graphene field-effect transistor (GFET) biosensors exhibit high sensitivity due to a large surface-to-volume ratio and the high sensitivity of the Fermi level to the presence of charged biomolecules near the surface. For most reported GFET biosensors, bulky external reference electrodes are used which prevent their full-scale chip integration and contribute to higher costs per test. In this study, GFET arrays with on-chip integrated liquid electrodes were employed for COVID-19 detection and functionalized with either antibody or aptamer to selectively bind the spike proteins of SARS-CoV-2. In the case of the aptamer-functionalized GFET (aptasensor, Apt-GFET), the limit-of-detection (LOD) achieved was about 103 particles per mL for virus-like particles (VLPs) in clinical transport medium, outperforming the Ab-GFET biosensor counterpart. In addition, the aptasensor achieved a LOD of 160 aM for COVID-19 neutralizing antibodies in serum. The sensors were found to be highly selective, fast (sample-to-result within minutes), and stable (low device-to-device signal variation; relative standard deviations below 0.5%). A home-built portable readout electronic unit was employed for simultaneous real-time measurements of 12 GFETs per chip. Our successful demonstration of a portable GFET biosensing platform has high potential for infectious disease detection and other health-care applications

    High-Throughput Mass Measurement Of Single Bacterial Cells By Silicon Nitride Membrane Resonators

    Get PDF
    Trabajo presentado en la 36th International Conference on Micro Electro Mechanical Systems (MEMS), celebrada en Munich (Alemania), del 15 al 19 de enero de 2023.© 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.We present a technological approach to precisely measure the dry mass of many individual cells of a bacteria colony. In this technique, bacteria are transported from aqueous solution into gas phase and subsequently guided to the surface of a silicon nitride membrane resonator. Abrupt downshifts in the membrane eigenfrequencies are measured upon every bacterium adhesion and are related to the dry mass of the cell by theoretical methods. We measure the dry mass of Escherichia coli K-12 and Staphylococcus epidermidis with an unprecedented throughput of 20 cells/min and with a mass resolution of ⁓1%. Finally, we apply the Koch & Schaechter model to assess the intrinsic sources of growth stochasticity.This work was supported by the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 731868-VIRUSCAN and by the ERC CoG Grant 681275 “LIQUIDMASS”. We acknowledge the service from the Micro and Nanofabrication Laboratory an X-SEM laboratory at IMNCNM funded by the Comunidad de Madrid (Project S2018/NMT-4291 TEC2SPACE) and by MINECO (Project CSIC12-4E-1794 with support from FEDER, FSE). E. G. S. acknowledges financial support by the Spanish Science and Innovation Ministry through Ramón y Cajal grant RYC-2019-026626-I

    Mid-term outcomes in the treatment of retroperitoneal sarcomas: a 12-year single-institution experience

    Get PDF
    Aim To present the experience from collective data regarding patients with retroperitoneal sarcomas that have been operated in and followed up by the University General Hospital of Patras in Rion, Greece, between 2009 and 2020. Methods A retrospective analysis of adult patients treated at our hospital with a diagnosis of primary retroperitoneal sarcoma who underwent tumour resection. Results Data from 29 patients were analysed. The mean age at diagnosis was 56.1 years; 55.2% of patients were male (n=16). Liposarcomas (on histology) were identified in 19 (65.5%) patients, leiomyosarcoma six (20.7%), and other histologic subtypes in four (13.8%) patients. Tumours >5cm were presented in 27 (93.1%) patients. Negative margins were attained in 13 (44.8%) of all patients who underwent surgical resection. Five (17.2%) patients received neoadjuvant radiation, four (13.8%) postoperative radiation, and three (10.3%) patients received both chemotherapy and radiation prior to surgery with the rest of the patients being treated with surgical excision alone. A 3-year follow-up was successful in 21 (72.4%) patients; five (23.8%) patients died. In total, 16 (55.2%) patients were found to have a local recurrence, with no significant difference in patients' age, gender, tumour size, histology, negative surgical margin (Ro) resection, neoadjuvant chemotherapy, or radiation therapy. There was a significant difference in the 3-year survival rate between patients having positive or negative surgical margins (p=0.027). Conclusion The higher 3-year survival rate in patients with retroperitoneal sarcomas when achieving Ro resection warrant further investigation with a larger sample size across different institutions

    Corrigendum to "Recognition motifs for importin 4 [(L)PPRS(G/P)P] and importin 5 [KP(K/Y)LV] binding, identified by bio-informatic simulation and experimental in vitro validation" [Comput Struct Biotechnol J 20 (2022) 5952-5961]

    Get PDF
    Nuclear translocation of large proteins is mediated through karyopherins, carrier proteins recognizing specific motifs of cargo proteins, known as nuclear localization signals (NLS). However, only few NLS signals have been reported until now. In the present work, NLS signals for Importins 4 and 5 were identified through an unsupervised in silico approach, followed by experimental in vitro validation. The sequences LPPRS(G/P)P and KP(K/Y)LV were identified and are proposed as recognition motifs for Importins 4 and 5 binding, respectively. They are involved in the trafficking of important proteins into the nucleus. These sequences were validated in the breast cancer cell line T47D, which expresses both Importins 4 and 5. Elucidating the complex relationships of the nuclear transporters and their cargo proteins is very important in better understanding the mechanism of nuclear transport of proteins and laying the foundation for the development of novel therapeutics, targeting specific importins
    corecore