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Population screening of newborns is an extremely important and informative diagnostic approach that allows early identification of babies who are predisposed to the development of a number of serious diseases. Some of these diseases are known and have effective treatment methods. Neonatal screening enables the early diagnosis and subsequent timely initiation of therapy. This helps to prevent serious complications and reduce the percentage of disability and deaths among newborns and young children. Primary immunodeficiency diseases and primary immunodeficiency syndrome (PIDS) are a heterogeneous group of diseases and conditions based on impaired immune system function associated with developmental defects and characterized by various combinations of recurrent infections, development of autoimmune and lymphoproliferative syndromes (genetic defects in apoptosis, gene mutation Fas receptor or ligand), granulomatous process, and malignant neoplasms. Most of these diseases manifest in infancy and lead to serious illness, disability, and high mortality rates. Until recently, it was impossible to identify children with PIDS before the onset of the first clinical symptoms, which are usually accompanied by complications in the form of severe coinfections of a viralbacterial-fungal etiology. Modern advances in medical laboratory technology have allowed the identification of children with severe PIDS, manifested by T- and/or B-cell lymphopenia and other disorders of the immune system. This review discusses the main existing strategies and directions used in PIDS screening programs for newborns, including approaches to screening based on excision of T-cell receptors and kappa-recombination excision circles, as well as the potential role and place of nextgeneration sequencing technology to increase the diagnostic accuracy of these diseases. [ABSTRACT FROM AUTHOR]

This paper presents results of a numerical finite element parametric study on elastic shear buckling and ultimate shear strength of cold-formed steel channels with longitudinally stiffened slotted webs. The following parameters were varied: channel height, thickness, flange width, flange lip length, longitudinal stiffener size, perforation pattern, aspect ratio, steel yield stress and boundary conditions. Channels with longitudinally stiffened solid webs subjected to shear load were also studied to provide reference data for comparison with the slotted channels. The parametric study described in this paper allowed us to develop equations for predicting the shear buckling coefficient of longitudinally web stiffened solid channels, as well as equations for predicting the elastic shear buckling load and the ultimate shear strength of channels with longitudinally stiffened slotted webs. The developed shear strength equations without and with tension field action are presented in the paper in the traditional and direct strength method formulations. The developed equations account for the studied parameters and showed good agreements with the finite element simulation results. [ABSTRACT FROM AUTHOR]

This paper presents results of a numerical parametric study on the ultimate shear strength of cold-formed steel channels with flat slotted webs. The study was performed on nonlinear finite element models developed in ANSYS and validated against test data. The effects of perforation pattern, channel flange width, flange lip length, steel yield stress, and aspect ratio on the ultimate shear strength of the channels were numerically investigated on the models with realistic and test setup boundary conditions. Equations for predicting the shear strength of channels with flat slotted webs were developed. The equations account for the effects of the studied parameters on the shear strength of the channels and showed a good agreement with the finite element analysis results when post-buckling shear strength due to tension field action was taken into account. [ABSTRACT FROM AUTHOR]

This paper presents results of a numerical parametric study on elastic shear buckling of cold-formed steel channels with flat slotted webs. The study was performed on finite element models developed in ANSYS and validated against test data. The effects of perforation pattern, channel flange width, flange lip length, and aspect ratio on the elastic shear buckling load were investigated on the models with realistic and test setup boundary conditions. Equations for predicting the elastic shear buckling load of slotted channels were developed. The equations account for the effects of the studied parameters on the elastic shear buckling load of cold-formed steel channels with flat slotted webs and showed a good agreement with the finite element analysis results. [ABSTRACT FROM AUTHOR]

Cold-formed steel studs and purlins with slotted webs including staggered perforations are used in building construction to enhance the thermal performance and energy efficiency of buildings. However, the web perforations adversely affect their structural capacities, especially their shear and web crippling capacities. Limited research has been reported on this subject despite its importance and continuing use of channel sections with staggered web perforations. Hence a series of web crippling tests was undertaken to investigate the web crippling behaviour and capacities of cold-formed steel channels with staggered web perforations under two flange load cases with their flanges unfastened to the supports. Forty eight lipped channel specimens with perforated and solid webs were tested to failure. Comparison of the experimental web crippling capacities of slotted and solid channels showed that the presence of staggered web perforations significantly reduced the web crippling capacities of channel sections. New web crippling capacity design equations are proposed to calculate the reduced web crippling capacities of lipped channel sections with staggered web perforations. This paper presents the details and results of this experimental investigation. • Investigated the web crippling capacity of cold-formed channels with staggered slotted perforations. • Conducted 48 web crippling tests under two flange load cases with flanges unfastened to supports. • Staggered slotted perforations significantly reduced the web crippling capacity. • The web crippling strength reduction depended on channel thickness and depth. • Proposed design equations to predict the web crippling capacity of channels with slotted webs. [ABSTRACT FROM AUTHOR]

Providing staggered slotted perforations to the Cold-Formed Steel (CFS) beams is a new approach being used in light gauge steel construction aiming to enhance both the fire and energy performances. However, slots in the web reduce the load-bearing capacity of CFS beams and existing studies do not provide a definite evaluation of the design expressions to determine the structural performance of slotted perforated CFS flexural members. Therefore, the present study aims to establish a methodology to determine the flexural capacity of staggered slotted perforated CFS beams subject to local buckling through developing three-dimensional Finite Element (FE) models. The developed FE models were subjected to validation against the related test data. Subsequently, the validated FE model was employed to conduct further parametric studies (432 FE models). Parameters include the dimensions of the CFS beams and staggered slotted perforations, rows and row groups of slots and yield strength. The effect of these factors on the local buckling capacity of the staggered slotted perforated CFS beams under bending is discussed. The paper concludes with a proposal of Direct Strength Method (DSM) based new design equations to predict the bending capacity of the CFS beams with staggered slotted perforations subject to local buckling and to enhance their commercial aspects. • Investigated the local buckling behaviour of CFS beams with staggered slotted perforations. • Suitable non-linear finite element models were developed and calibrated using test data. • Extensive finite element parametric analyses were undertaken considering all the influencing parameters. • Staggered slotted perforations reduced the local buckling flexural capacity with a maximum reduction value of 11%. • The current DSM was extended for the design of staggered slotted perforated CFS beams subject to local buckling. [ABSTRACT FROM AUTHOR]

Cold-Formed Steel (CFS) members with slotted perforations in webs are used in civil construction to amplify the thermal and energy performance of structures. However, the slotted webs reduce the structural performance of the element, prominently their shear, bending and combined bending and shear strengths. Many research studies have been undertaken to examine the behaviour of CFS channel sections subject to bending. Yet, no research has been performed to investigate the distortional buckling behaviour of slotted perforated CFS flexural members. Finite Element (FE) models of CFS channels with staggered slotted perforations were developed herein to investigate their distortional buckling under bending stress. A parametric study was conducted in detail by developing 432 slotted perforated CFS FE models based on the validation process with available experimental results. In particular, this paper presents the FE analysis details of CFS flexural members with slotted perforations subject to distortional buckling and results. The reliability of the current Direct Strength Method (DSM) for CFS flexural members with web holes subject to distortional buckling in accordance with the North American Specification (AISI S100) (2016) and the Australian/New Zealand Standards (AS/NZ 4600) (2018) was investigated. Modified DSM formulae for slotted perforated CFS flexural members subject to distortional buckling were also proposed. • Distortional buckling behavior of CFS beams with staggered slotted perforations have been investigated. • Finite element models showed good agreement with available test data. • All influencing parameters were considered in the parametric studies. • Staggered slotted perforations reduced the distortional buckling flexural capacity up to 23%. • New direct strength method based design equations were proposed for distortional buckling. [ABSTRACT FROM AUTHOR]

Unlike classic APS, CAPS causes multiple microthrombosis due to an increased inflammatory response, known as a "thrombotic storm". CAPS typically develops after infection, trauma, or surgery and begins with the following symptoms: fever, thrombocytopenia, muscle weakness, visual and cognitive disturbances, abdominal pain, renal failure, and disseminated intravascular coagulation. Although the presence of antiphospholipid antibodies in the blood is one of the diagnostic criteria, the level of these antibodies can fluctuate significantly, which complicates the diagnostic process and can lead to erroneous interpretation of rapidly developing symptoms. Triple therapy is often used to treat CAPS, which includes the use of anticoagulants, plasmapheresis, and high doses of glucocorticosteroids and, in some cases, additional intravenous immunoglobulins. The use of LMWH is recommended as the drug of choice due to its anti-inflammatory and anticoagulant properties. CAPS is a multifactorial disease that requires not only an interdisciplinary approach but also highly qualified medical care, adequate and timely diagnosis, and appropriate prevention in the context of relapse or occurrence of the disease. Improved new clinical protocols and education of medical personnel regarding CAPS can significantly improve the therapeutic approach and reduce mortality rates. [ABSTRACT FROM AUTHOR]

Newborns are the most vulnerable patients for thrombosis development among all children, with critically ill and premature infants being in the highest risk group. The upward trend in the rate of neonatal thrombosis could be attributed to progress in the treatment of severe neonatal conditions and the increased survival in premature babies. There are physiological differences in the hemostatic system between neonates and adults. Neonates differ in concentrations and rate of synthesis of most coagulation factors, turnover rates, the ability to regulate thrombin and plasmin, and in greater variability compared to adults. Natural inhibitors of coagulation (protein C, protein S, antithrombin, heparin cofactor II) and vitamin K-dependent coagulation factors (factors II, VII, IX, X) are low, but factor VIII and von Willebrand factor are elevated. Newborns have decreased fibrinolytic activity. In the healthy neonate, the balance is maintained but appears more easily converted into thrombosis. Neonatal hemostasis has less buffer capacity, and almost 95% of thrombosis is provoked. Different triggering risk factors are responsible for thrombosis in neonates, but the most important risk factors for thrombosis are central catheters, fluid fluctuations, liver dysfunction, and septic and inflammatory conditions. Low-molecular-weight heparins are the agents of choice for anticoagulation. [ABSTRACT FROM AUTHOR]

Background: Contracting COVID-19 during pregnancy can harm both the mother and the unborn child. Pregnant women are highly likely to develop respiratory viral infection complications with critical conditions caused by physiological changes in the immune and cardiopulmonary systems. Asymptomatic COVID-19 in pregnant women may be accompanied by fetal inflammatory response syndrome, which has adverse consequences for the newborn's life and health. Purpose: To conduct an inflammatory response assessment of the fetus due to the effects of COVID-19 on the mother during pregnancy by determining pro-inflammatory cytokines, cell markers, T regulatory cells, T cell response, evaluation of cardiac function, and thymus size. Materials and methods: A prospective study included pregnant women (n = 92). The main group consisted of 62 pregnant women with COVID-19 infection: subgroup 1—SARS-CoV-2 PCR-positive pregnant women 4–6 weeks before delivery (n = 30); subgroup 2—SARS-CoV-2 PCR-positive earlier during pregnancy (n = 32). The control group consisted of 30 healthy pregnant women. In all pregnant women, the levels of circulating cytokines and chemokines (IL-1α, IL-6, IL-8, IL-10, GM-CSF, TNF-α, IFN-γ, MIP-1β, and CXCL-10) were determined in the peripheral blood and after delivery in the umbilical cord blood, and an analysis was performed of the cell markers on dendritic cells, quantitative and functional characteristics of T regulatory cells, and specific T cell responses. The levels of thyroxine and thyroid-stimulating hormone were determined in the newborns of the studied groups, and ultrasound examinations of the thymus and echocardiography of the heart were also performed. Results: The cord blood dendritic cells of newborns born to mothers who suffered from COVID-19 4–6 weeks before delivery (subgroup 1) showed a significant increase in CD80 and CD86 expression compared to the control group (p = 0.023). In the umbilical cord blood samples of children whose mothers tested positive for COVID-19 4–6 weeks before delivery (subgroup 1), the CD4+CCR7+ T cells increased with a concomitant decrease in the proportion of naive CD4+ T cells compared with the control group (p = 0.016). Significantly higher levels of pro-inflammatory cytokines and chemokines were detected in the newborns of subgroup 1 compared to the control group. In the newborns of subgroup 1, the functional activity of T regulatory cells was suppressed, compared with the newborns of the control group (p < 0.001). In all pregnant women with a severe coronavirus infection, a weak T cell response was detected in them as well as in their newborns. In newborns whose mothers suffered a coronavirus infection, a decrease in thymus size, transient hypothyroxinemia, and changes in functional parameters according to echocardiography were revealed compared with the newborns of the control group. Conclusions: Fetal inflammatory response syndrome can occur in infants whose mothers suffered from a COVID-19 infection during pregnancy and is characterized by the activation of the fetal immune system and increased production of pro-inflammatory cytokines. The disease severity in a pregnant woman does not correlate with SIRS severity in the neonatal period. It can vary from minimal laboratory parameter changes to the development of complications in the organs and systems of the fetus and newborn. [ABSTRACT FROM AUTHOR]

This paper focuses on the web crippling performance of staggered slotted perforated Cold-Formed Steel (CFS) channels under Interior-One-Flange (IOF) load case, highlights the web crippling strength reduction, and provides reliable design guidelines. Finite Element (FE) analysis was employed to represent the IOF load case web crippling behaviour of staggered slotted perforated CFS channels. The developed FE models were then validated against laboratory tests on web crippling of CFS channels with both solid web and web openings under IOF load case. A parametric study (288 models) was conducted using the validated models to assess the effect of staggered slotted configurations and the corresponding degree of reduction in web crippling strength. It is shown that staggered slotted perforations play an important role in defining performance and may lead to a considerable reduction (up to 49%) in web crippling strength. Based on the results of the parametric study, new web crippling design equations were developed for IOF load case accounting the staggered slotted perforations. The web crippling strength predictions using the proposed equations yielded at a much higher level of accuracy, enhancing the commercial aspects of slotted perforated channels. [Display omitted] • Investigated the web crippling behaviour of CFS beams with staggered slotted perforations under IOF loading. • Non-linear finite element models were developed and validated against web crippling test results. • Parametric finite element analyses were undertaken considering all key influencing parameters. • Staggered slotted perforations reduced the web crippling strength with a maximum reduction value of 49%. • A new web crippling design approach was developed to capture the effect of staggered slotted perforations. [ABSTRACT FROM AUTHOR]