On conformal curves in 2-dimensional de sitter space

In this paper, we examine the pseudo-spherical curves, which are equivalent to each other under the conformal maps preserving a fixed point in the de Sitter 2-space, by using the Clifford algebra Cl 2,1. Also, we find the parametric equations of de Sitter loxodromes.No sponso

Some results on p-shape curvatures of non-lightlike space curves

In this paper, we obtain some findings for a non-null curve parameterized by spherical arc length. We investigate the relationship between a non-null curve with p-shape curvatures and pseudospherical curves on S21 and H2(−1). We introduce the concept of similar helix in Minkowski 3-space E31. Besides, we explicitly determine the parametrizations of all non-lightlike self-similar curves by using the pseudo-spherical curves in E31.No sponso

Similar and self-similar curves in minkowski n-space

In this paper, we investigate the similarity transformations in the Minkowski n-space. We study the geometric invariants of nonnull curves under the similarity transformations. Besides, we extend the fundamental theorem for a non-null curve according to a similarity motion of En1. We determine the parametrizations of non-null self-similar curves in En1. .No sponso

Microstructural Characterization and Deformation of X10CrAlSi24 Sheet Material Applied V-Bending Process

This study used X10CrAlSi24 (1.4762) sheet material, which is widespread in bending processes of the energy sector. During bending of X10CrAlSi24 (1.4762) sheet materials, cracking and tearing occur due to these materials’ brittleness at room temperatures. To avoid this phenomenon, bending was carried out by applying normalization treatments at 800 ºC, 850 ºC, 900 ºC and 950 ºC. V-bending processes were performed at three different bending angles (30º, 60º, 90º) and by a 4.5 mm punch tip radius. V-bending processes were carried out without leaving the punch on the material, and crushing of the punch on the sheet material sectional area was allowed. As a result of the bending processes, spring-go occurred in the 30º and 60º bending applications, whereas spring-back occurred in the 90º bending applications. The formation mechanism of capillary cracks (depending on deformation) due to internal stress especially at low temperatures was introduced by the microstructural characterization of the specimens

On the eigenvalues and eigenvectors of a lorentzian rotation matrix by using split quaternions

In this paper, we examine eigenvalue problem of a rotation matrix in Minkowski 3 space by using split quaternions. We express the eigenvalues and the eigenvectors of a rotation matrix in term of the coefficients of the corresponding unit timelike split quaternion. We give the characterizations of eigenvalues (complex or real) of a rotation matrix in Minkowski 3 space according to only first component of the corresponding quaternion. Moreover, we find that the casual characters of rotation axis depend only on first component of the corresponding quaternion. Finally, we give the way to generate an orthogonal basis for 31 by using eigenvectors of a rotation matrix.No sponso

Nadir bir sinüs enfeksiyonu etkeni olarak citrobacter koseri: bir olgu raporu

Maksiller posterior bölgede yapılan diş çekimleri sırasında maksiller sinüs ile ilişkili çok sayıda komplikasyon ile karşılaşılmaktadır. Diş kökenli maksiller sinüzitlerin %10’unu oluşturan sinüse kök kaçırılması dental kaynaklı nedenlerden birisidir. Literatürde dental kaynaklı sinüs enfeksiyonu oluşturabilen birçok bakteri türünden bahsedilmesine rağmen, enterik bir bakteri olan Citrobacter koseri (C. koseri) nadir görülen bir sinüs enfeksiyonu etkenidir. 34 yaşındaki, bayan hasta, kliniğimize üst çene sağ taraf büyükazı dişler bölgesinde ağrı şikayeti ile başvurdu. Yapılan radyografik inceleme sonucunda hastanın maksiller sinüsünde rezidüel kök tespit edildi. Mevcut residüel kök Caldwel Luc cerrahisi ile çıkarıldı. Hastanın şikayetleri ortadan kalktı. Yeşil renkli olan diş kökü mikrobiyoloji laboratuvarında anaerobik ve aerobik olarak kültüre edildi. 37 °C’taki 24 saatlik aerobik inkübasyonu takiben gram negatif basil morfolojisine sahip saf koloniler saptandı. Koloniler konvansiyonel yöntemlerin yanısıra VITEK2 Compact otomatik identifikasyon sistemi ile de C. koseri olarak tanımlandı

Self-reported antibiotic stewardship and infection control measures from 57 intensive care units: An international ID-IRI survey

We explored the self-reported antibiotic stewardship (AS), and infection prevention and control (IPC) activities in intensive care units (ICUs) of different income settings. A cross-sectional study was conducted using an online questionnaire to collect data about IPC and AS measures in participating ICUs. The study participants were Infectious Diseases-International Research Initiative (IDI-IR) members, committed as per their institutional agreement form. We analyzed responses from 57 ICUs in 24 countries (Lower-middle income (LMI), n = 13; Upper-middle income (UMI), n = 33; High-income (HI), n = 11). This represented (similar to 5%) of centers represented in the ID-IRI. Surveillance programs were implemented in (76.9%-90.9%) of ICUs with fewer contact precaution measures in LMI ones (p = 0.02); (LMI:69.2%, UMI:97%, HI:100%). Participation in regional antimicrobial resistance programs was more significantly applied in HI (p = 0.02) (LMI:38.4%,UMI:81.8%,HI:72.2%). AS programs are implemented in 77.2% of institutions with AS champions in 66.7%. Infectious diseases physicians and microbiologists are members of many AS teams (59%&50%) respectively. Unqualified healthcare professionals(42.1%), and deficient incentives(28.1%) are the main barriers to implementing AS. We underscore the existing differences in IPC and AS programs' implementation, team composition, and faced barriers. Continuous collaboration and sharing best practices on APM is needed. The role of regional and international organizations should be encouraged. Global support for capacity building of healthcare practitioners is warranted. (C) 2022 Published by Elsevier Ltd on behalf of King Saud Bin Abdulaziz University for Health Sciences