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Magnetosheath jets represent localized enhancements in dynamic pressure observed within the magnetosheath. These energetic entities, carrying excess energy and momentum, can impact the magnetopause and disrupt the magnetosphere. Therefore, they play a vital role in coupling the solar wind and terrestrial magnetosphere. However, our understanding of the morphology and formation of these complex, transient events remains incomplete over two decades after their initial observation. Previous studies have relied on oversimplified assumptions, considering jets as elongated cylinders with dimensions ranging from |$0.1\, R_{\rm E}$| to |$5\, R_{\rm E}$| (Earth radii). In this study, we present simulation results obtained from Amitis, a high-performance hybrid-kinetic plasma framework (particle ions and fluid electrons) running in parallel on graphics processing units (GPUs) for fast and more environmentally friendly computation compared to CPU-based models. Considering realistic scales, we present the first global, three-dimensional (3D in both configuration and velocity spaces) hybrid-kinetic simulation results of the interaction between solar wind plasma and the Earth. Our high-resolution kinetic simulations reveal the 3D structure of magnetosheath jets, showing that jets are far from being simple cylinders. Instead, they exhibit intricate and highly interconnected structures with dynamic 3D characteristics. As they move through the magnetosheath, they wrinkle, fold, merge, and split in complex ways before a subset reaches the magnetopause. [ABSTRACT FROM AUTHOR]

Electronic exchange of health care data demands code/terminology systems. In the Scandinavian countries, the IFCC-IUPAC's Nomenclature for Properties and Units (NPU) terminology is used for results in biochemistry, pharmacology, and immunology. Implementation, use and administration of NPU has differed between the countries despite similar health care and lab sectors. In Norway and in one Swedish region NPU - with supplementary SNOMED CT codes is also used for reporting results in microbiology. In Denmark and to some extent in Norway and Sweden NPU is also used for ordering tests. In Norway NPU (as part of NLK) has since 2018 been mandatory in requesting governmental reimbursement for laboratory tests. The numbers of national codes vary considerably (DAN: 303, NOR: 1612, SWE: 415). Furthermore, in Denmark >3500 local codes are used for requisition and to communicate more details with the analytical result than the NPU terminology allows. Also, in Norway the NPU codes are by many lab professionals considered insufficient for communicating all relevant information with results. However, the Norwegian reimbursement system has been a strong motivator for implementing international NPU codes. We find it necessary to add information about "how" a measurement is done to the information about "what" is measured in the laboratory report. Until this is settled otherwise, we suggest an increased pragmatism towards producing national codes including method specific information. Furthermore, we recommend that organisations responsible for classifications have heavy professional participation and decision-making competencies in order to lead and guide implementation and optimal use of the classifications., Competing Interests: Declaration of Conflict of interests The authors of this article declare that there is no conflict of interest with regard to the content of this manuscript. R. Ceder, K. Toska,, Y.B. Hansen and G. Nordin are, or have been, members of the IFCC committee on Nomenclature, Properties and Units (C-NPU) in collaboration with IUPAC., (Copyright © 2024 International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). All rights reserved.)

Estimation of kidney function is often part of daily clinical practice, mostly done by using the endogenous glomerular filtration rate (GFR)-markers creatinine or cystatin C. A recommendation to use both markers in parallel in 2010 has resulted in new knowledge concerning the pathophysiology of kidney disorders by the identification of a new set of kidney disorders, selective glomerular hypofiltration syndromes. These syndromes, connected to strong increases in mortality and morbidity, are characterized by a selective reduction in the glomerular filtration of 5-30 kDa molecules, such as cystatin C, compared to the filtration of small molecules <1 kDa dominating the glomerular filtrate, for example water, urea and creatinine. At least two types of such disorders, shrunken or elongated pore syndrome, are possible according to the pore model for glomerular filtration. Selective glomerular hypofiltration syndromes are prevalent in investigated populations, and patients with these syndromes often display normal measured GFR or creatinine-based GFR-estimates. The syndromes are characterized by proteomic changes promoting the development of atherosclerosis, indicating antibodies and specific receptor-blocking substances as possible new treatment modalities. Presently, the KDIGO guidelines for diagnosing kidney disorders do not recommend cystatin C as a general marker of kidney function and will therefore not allow the identification of a considerable number of patients with selective glomerular hypofiltration syndromes. Furthermore, as cystatin C is uninfluenced by muscle mass, diet or variations in tubular secretion and cystatin C-based GFR-estimation equations do not require controversial race or sex terms, it is obvious that cystatin C should be a part of future KDIGO guidelines., (© 2022 The Authors. Journal of Internal Medicine published by John Wiley & Sons Ltd on behalf of Association for Publication of The Journal of Internal Medicine.)

Background: Few studies are available on how to optimize time points for sampling and how to estimate effects of analytical uncertainty when glomerular filtration rate (GFR) is calculated., Methods: We explored the underlying regression mathematics of how analytical variation of a kidney filtration marker affects 1-compartment, slope-and-intercept GFR calculations, using 2 or 3 time points following a bolus injection, and used this to examine the results from 731 routine 3-point iohexol plasma clearance measurements., Results: GFR calculations inflated analytical uncertainty if the time points were taken too late after the bolus injection and too close after each other. The uncertainty in GFR calculation was, however, the same as the analytical uncertainty if optimal time points were used. The middle of the 3 samples was of little value. The first sample should be taken as early as possible after the distribution phase. Sampling before the patient specific half-life of the kidney filtration marker resulted in an exponential error inflation whereas no error inflation was seen when sampling occurred later than 2 half-lives. Theoretical GFR uncertainty could be lowered 2.6-fold if individually optimized time points for sampling had been used in our 731 clearance measurements. Using Taylor expansions to approximate the moments of transformed random variables, the uncertainty of an individual GFR measurement could be calculated in a simple enough way to be applicable by laboratory software., Conclusions: We provide a theoretical foundation to select patient-optimal time points that may both limit errors and allow calculation of GFR uncertainty., Competing Interests: Authors’ Disclosures or Potential Conflicts of Interest: Upon manuscript submission, all authors completed the author disclosure form. Disclosures and/or potential conflicts of interest:, (© American Association for Clinical Chemistry 2022.)

Current criteria for the diagnosis of CKD in adults include persistent signs of kidney damage, such as increased urine albumin-to-creatinine ratio or a GFR below the threshold of 60 ml/min per 1.73 m 2 This threshold has important caveats because it does not separate kidney disease from kidney aging, and therefore does not hold for all ages. In an extensive review of the literature, we found that GFR declines with healthy aging without any overt signs of compensation (such as elevated single-nephron GFR) or kidney damage. Older living kidney donors, who are carefully selected based on good health, have a lower predonation GFR compared with younger donors. Furthermore, the results from the large meta-analyses conducted by the CKD Prognosis Consortium and from numerous other studies indicate that the GFR threshold above which the risk of mortality is increased is not consistent across all ages. Among younger persons, mortality is increased at GFR <75 ml/min per 1.73 m 2 , whereas in elderly people it is increased at levels <45 ml/min per 1.73 m 2 Therefore, we suggest that amending the CKD definition to include age-specific thresholds for GFR. The implications of an updated definition are far reaching. Having fewer healthy elderly individuals diagnosed with CKD could help reduce inappropriate care and its associated adverse effects. Global prevalence estimates for CKD would be substantially reduced. Also, using an age-specific threshold for younger persons might lead to earlier identification of CKD onset for such individuals, at a point when progressive kidney damage may still be preventable., (Copyright © 2019 by the American Society of Nephrology.)

Many decisions within healthcare are based on results from laboratory tests. These results all have an uncertainty, which can be either neglectable or large enough to affect the clinical assessment. In external quality assessment (EQA) the laboratories make independent observations on the same control sample, with values unknown for the participants. The results can be used to determine if quality improvement is needed. We present EQA data for laboratory tests with three different measurement scales; quantitative, ordinal and nominal. Results from EQA should be used in the discussions of quality in test results and necessary analytical performance specifications should be agreed upon.

Background: The accuracy and trueness of results from a laboratory test, such as the HbA1c test, should not be taken for granted but must be checked continuously. A tool for this is the participation in external quality assessment (EQA) for all laboratories performing the HbA1c-test. An additional possibility to detect changes in trueness is to monitor variations in patient cohort mean or median values that is not explained by changes in treatment or selection of patients., Methods: Results reported to an EQA scheme for HbA1c during 20 years have been extracted from Equalis database. The results are compared to current analytical performance specifications (APS) and to the mean HbA1c levels for the Swedish population of persons with type 2 diabetes., Results: The accuracy of the HbA1c test has improved during the period. The hospital lab methods used in Sweden now fulfil APS agreed by professional organizations in Sweden. The accuracy for point-of-care tests (POCT) methods vary over time and fulfil APS for some periods. The bias found for some of the methods might explain changes seen in patient mean values for HbA1c in Sweden during the period 2007-2017., Conclusions: The global standardization of HbA1c has resulted in an improved comparability for HbA1c-results worldwide. But even small variation in trueness for the methods in use might have important impact on mean HbA1c values for cohorts of patients. When a systematic error is observed for a specific method it is therefore essential that manufacturers correct the method without delay.

Background: Many different cystatin C-based equations exist for estimating glomerular filtration rate. Major reasons for this are the previous lack of an international cystatin C calibrator and the nonequivalence of results from different cystatin C assays., Methods: Use of the recently introduced certified reference material, ERM-DA471/IFCC, and further work to achieve high agreement and equivalence of 7 commercially available cystatin C assays allowed a substantial decrease of the CV of the assays, as defined by their performance in an external quality assessment for clinical laboratory investigations. By use of 2 of these assays and a population of 4690 subjects, with large subpopulations of children and Asian and Caucasian adults, with their GFR determined by either renal or plasma inulin clearance or plasma iohexol clearance, we attempted to produce a virtually assay-independent simple cystatin C-based equation for estimation of GFR., Results: We developed a simple cystatin C-based equation for estimation of GFR comprising only 2 variables, cystatin C concentration and age. No terms for race and sex are required for optimal diagnostic performance. The equation, [Formula: see text] is also biologically oriented, with 1 term for the theoretical renal clearance of small molecules and 1 constant for extrarenal clearance of cystatin C., Conclusions: A virtually assay-independent simple cystatin C-based and biologically oriented equation for estimation of GFR, without terms for sex and race, was produced., (© 2014 The American Association for Clinical Chemistry.)