Search

We use the effective field theory with a probability distribution technique to investigate the magnetic properties of an antiferromagnetic Ising core/shell nanoparticle with a negative interlayer coupling core/shell in the presence of both the longitudinal and the transverse fields. Nearest-neighbor pair interactions are incorporated between the Ising spins in three parts that are core, core/shell, and surface shell. The effects of the external and the transverse fields and the exchange interactions between core/shell and in surface shell on the hysteresis loops and the susceptibility of the nanoparticle are examined. A number of interesting phenomena have been found. [ABSTRACT FROM AUTHOR]

The medical screening practices for blood donor eligibility after vaccination against several conventional infectious agents are well known to blood transfusion centres worldwide. Classically, blood donations are contraindicated for four weeks after vaccination with a live attenuated virus vaccine. For other types of vaccines, no postponement is necessary as there is no proven infectious risk. But for the COVID-19 vaccine, besides the classic platforms for the vaccine, two new types of vaccine platforms have been developed and based on viral vectors vaccines and vaccines from viral genetic material. Thus, blood establishments could be worried that these COVID-19 vaccine production platforms can pose any particular safety concerns for recipients of blood or blood products from vaccinated subjects. Our work aims to provide professionals in blood transfusion centres with all the available information to clarify any confusion relating to the need or not to defer donors who have received a COVID-19 vaccination. So in this paper, we provide an international review of the data available to date about the recommendations of international scientific societies about blood donation after COVID-19 vaccination, all types of COVID-19 vaccines included. We also present some experiences of blood transfusion establishments worldwide concerning this topic and among them our institution, the Moroccan National Centre for Blood Transfusion and Haematology., Competing Interests: The authors declare no competing interests., (Copyright: Sabah Bouhou et al.)

At the end of 2019, a new coronavirus was identified in people living in the city of Wuhan in China. Since the appearance of the first cases in Wuhan, the SARS-CoV-2 epidemic has spread to the international scale. The COVID-19 pandemic is considered by international scientific societies to have an impact on blood donation and transfusion activities. Efforts must be made at the level of the transfusion centres to ensure proper management of the impact of this health crisis on the availability and the safety of blood products. The National Blood Centre of Morocco (MNBC) has demonstrated a great reactivity and a great adaptability since the beginning of the epidemic and has implemented several measures to face this health crisis. These measures have been updated taking into account the updating of data from national health authorities and international scientific societies concerning this new virus., Competing Interests: The authors declare no competing interests., (Copyright: Sabah Bouhou et al.)