bluuebunny/crossref_metadata_2025_split huggingface dataset:
External quality assessment (EQA) and alternative assessment procedures (AAPs) in molecular diagnostics: findings of an international survey
Authors: Payne Deborah A. , Russomando Graciela , Linder Mark W. , Baluchova Katarina , Ashavaid Tester , Steimer Werner , Ahmad-Nejad Parviz 
Published: May 2020

Abstract

Objectives
Quality management for clinical laboratories requires the establishment of internal procedures including standard operating procedures (SOPs), internal quality control (QC), validation of test results and quality assessment. External quality assessment (EQA) and alternativeassessment procedures (AAPs) are part of the quality hierarchy required for diagnostic testing. The International Organization for Standardization (ISO) document with requirements for conformance ISO 15189 and the Clinical and Laboratory Standards Institute document (CLSI) QMS24 require participation in EQA schemes and AAPs where applicable. The purpose of this study was to perform a global survey of EQA and AAPs for key procedures in molecular diagnostic laboratories.

Methods
The Committee for Molecular Diagnostics of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC C-MD) conducted a survey of international molecular laboratories that covered specific topics of molecular diagnostic services as well as methods for EQA and AAPs. The survey addressed the following aspects: (1) usage of laboratory-developed test (LDT), (2) participation in EQA schemes and (3) performance of AAPs.

Results
A total of 93 responses from laboratories located in Asia, Europe, the Middle East, North America and South America were received. The majority of the participating laboratories (65.9%) use LDTs and 81.3% stated that it is mandatory for them to participate in EQA programs, while 22% of the laboratories reported not performing AAPs. Thirty-one percent of the laboratories use EQAs for fewer than 50.0% of their reported parameters/analytes.

Conclusions
While the majority of laboratories perform EQA and AAPs to improve their quality in molecular diagnostics, the amount of AAPs as quality procedures differs within the laboratories. Further surveys are necessary to clarify the existing needs in additional EQAs and standardized AAPs. The survey will also guide future efforts of the IFCC C-MD for identifying quality practices in need to improve harmonization and standardization within molecular diagnostics.
Quality performance for indirect Xa inhibitor monitoring in patients using international external quality data
Authors: Hollestelle Martine J. , van der Meer Felix J.M. , Meijer Piet 
Published: May 2020

Abstract

Objectives
Chromogenic anti-activated factor X (FXa) assays are currently the “gold standard” for monitoring indirect anticoagulants. However, anti-FXa has been shown to vary according to the choice of reagents. In the present study, the performance of anti-FXa measurement was evaluated in order to gain more insight into the clinical applications. Furthermore, the longitudinal coefficient of variation (CV) was studied to investigate whether there is improvement over time.

Methods
Laboratory tests results were evaluated for samples spiked with unfractionated heparin (UFH), low-molecular-weight-heparin (LMWH), fondaparinux and danaparoid sodium. External quality assessment (EQA) data from multiple years were used from more than 100 laboratories.

Results
Comparison of the results for all methods showed significant differences in measured values between the frequently used methods (ANOVA: p < 0.001). The largest differences were observed for LMWH and UFH measurements. These differences may be caused by differences in method composition, such as the addition of dextran sulphate. Substantial interlaboratory variation in anti-FXa monitoring was observed for all parameters, particularly at low concentrations. Our results showed that below 0.35 IU/mL, the CVs for UFH and LMWH increase dramatically and results below this limit should be used with caution.

Conclusions
Our study demonstrates that the choice of the anti-FXa method is particularly important for UFH and LMWH measurement. The variation in measurements may have an effect on clinical implications, such as therapeutic ranges. Furthermore, the longitudinal EQA data demonstrated a constant performance and, in at least 50% of the cases, improvement in the CV% of the anti-Xa results over time.
A novel mitochondrial m.14430A>G (MT-ND6, p.W82R) variant causes complex I deficiency and mitochondrial Leigh syndrome
Authors: Du Miaomiao , Wei Xiujuan , Xu Pu , Xie Anran , Zhou Xiyue , Yang Yanling , Li Dongxiao , Lyu Jianxin , Fang Hezhi 
Published: May 2020

Abstract

Objectives
Leigh syndrome (LS) is one of the most common mitochondrial diseases and has variable clinical symptoms. However, the genetic variant spectrum of this disease is incomplete.

Methods
Next-generation sequencing (NGS) was used to identify the m.14430A > G (p.W82R) variant in a patient with LS. The pathogenesis of this novel complex I (CI) variant was verified by determining the mitochondrial respiration, assembly of CI, ATP, MMP and lactate production, and cell growth rate in cybrids with and without this variant.

Results
A novel m.14430A > G (p.W82R) variant in the NADH dehydrogenase 6 (ND6) gene was identified in the patient; the mutant loads of m.14430A > G (p.W82R) in the patient were much higher than those in his mother. Although the transmitochondrial cybrid-based study showed that mitochondrial CI assembly remains unaffected in cells with the m.14430G variant, control cells had significantly higher endogenous and CI-dependent mitochondrial respiration than mutant cells. Accordingly, mutant cells had a lower ATP, MMP and higher extracellular lactate production than control cells. Notably, mutant cells had impaired growth in a galactose-containing medium when compared to wild-type cells.

Conclusions
A novel m.14430A > G (p.W82R) variant in the ND6 gene was identified from a patient suspected to have LS, and this variant impaired mitochondrial respiration by decreasing the activity of mitochondrial CI.
Dynamic profile and clinical implications of hematological parameters in hospitalized patients with coronavirus disease 2019
Authors: Ding Xiurong , Yu Yanhua , Lu Bichao , Huo Jianbo , Chen Ming , Kang Yanfang , Lou Jinli , Liu Zhizhong 
Published: May 2020

Abstract

Objectives
As people across the world suffer from coronavirus disease 2019 (COVID-19), further studies are needed to facilitate evaluating the severity and prognosis of COVID-19 patients. In the study, we aimed to dissect the dynamic profile and clinical implications of hematological findings in hospitalized patients with COVID-19.

Methods
We retrospectively analyzed the hematological findings of 72 patients with COVID-19 admitted from January 21 to February 17, 2020. The final date of follow-up was March 20, 2020. Dynamic profile of vital hematological parameters in severe and non-severe patients was presented at different time points (day 1, 5, 7, 9, 11, 13, 15 after admission), and the correlation of hematological parameters with hospitalization time was indicated.

Results
Of 72 patients with COVID-19, lymphopenia and leukopenia occurred in 39 (54.2%) and 20 (27.8%) patients with COVID-19, respectively. Fifteen (20.8%) patients were defined as severe cases and 57 (79.2%) were non-severe cases. Compared to non-severe patients, leukocyte count, neutrophil count and neutrophil-to-lymphocyte ratio (NLR) were significantly higher, whereas lymphocyte count was declined in severe patients at each time point. A growing trend in platelet count was found in non-severe patients over the follow-up period. In addition, a positive correlation of NLR with hospitalization time was detected from day 5 after admission.

Conclusions
Dynamic changes in vital hematological parameters from severe and non-severe patients had been characterized in the course of hospitalization. During hospitalization, NLR was found to have certain relevance to the hospitalization days and a role in forecasting disease prognosis for patients with COVID-19.
Reporting of D-dimer data in COVID-19: some confusion and potential for misinformation
Authors: Favaloro Emmanuel J. , Thachil Jecko 
Published: May 2020

Abstract
Coronavirus disease 2019 (COVID-19) represents a new pandemic caused by severe acute respiratory syndrome virus coronavirus 2 (SARS-CoV-2). A previous pooled analysis clearly identified elevated D-dimer levels as being associated with severity of COVID-19. Since then, several other studies have provided clearer support for this initial evidence. However, potentially under-recognized by those reporting on D-dimer is the considerable variation in reporting units for D-dimer, and thus also the potential for misreporting of D-dimer data based on poor or incomplete reporting. A PubMed search was used to identify recent papers reporting on D-dimers in COVID-19-based studies. We report that: (1) most publications did not identify either the manufacturer or D-dimer product used; (2) most did not identify whether D-dimer values were reported as D-dimer units (DDU) or fibrinogen equivalent units (FEU) (~2 ×  differences); (3) nearly half did not identify normal cut-off values; (4) some did not report numerical findings or units for D-dimer; (5) where reported, most identified units as either mg/L or μg/mL; (6) we identified at least four errors in reporting from 21 papers. It may not be possible to truly standardize D-dimer assays, but it should be feasible to harmonize D-dimer assays to a single unit of measurement.
Validation of a chemiluminescent assay for specific SARS-CoV-2 antibody
Authors: Tré-Hardy Marie , Wilmet Alain , Beukinga Ingrid , Dogné Jean-Michel , Douxfils Jonathan , Blairon Laurent 
Published: May 2020

AbstractObjectivesFaced with the COVID-19 pandemic and its impact on the availability and quality of both therapeutic and diagnostic methods, the Belgian authorities have decided to launch a procedure for additional evaluation of the performance of serological tests offered for sale on the national territory. This has been proposed with a double aim: (1) an in-depth verification of the analytical and clinical performances presented by the manufacturer and (2) an economy of scale in terms of centralized validation for all the laboratories using the tests subject to evaluation.MethodsA retrospective validation study was conducted including the serum of 125 patients in order to determine the analytical and clinical performances of the LIAISON®SARS-CoV-2 from DiaSorin®detecting anti-SARS-CoV-2 IgG and to compare its clinical performance with the enzyme-linked immunosorbent assay (ELISA) test from Euroimmun®, one of the first commercially available tests allowing the detection of anti-SARS-CoV-2 IgA and IgG.ResultsThe performances of the LIAISON®SARS-CoV-2 satisfied all the acceptance criteria and provided “real world” analytical and clinical performances very close to the ones reported by the manufacturer in its insert kit. Comparison between the LIAISON®SARS-CoV-2 and the ELISA method did not reveal any difference between the two techniques in terms of sensitivities and specificities regarding the determination of the IgG.ConclusionsThis study reports the validation of the LIAISON®SARS-CoV-2 allowing to detect IgG antibodies specifically directed against SARS-CoV-2. The analytical and clinical performances are excellent, and the automation of the test offers important rates, ideal for absorbing an extension of testing.
Biosafety measures for preventing infection from COVID-19 in clinical laboratories: IFCC Taskforce Recommendations
Authors: Lippi Giuseppe , Adeli Khosrow , Ferrari Maurizio , Horvath Andrea R. , Koch David , Sethi Sunil , Wang Cheng-Bin 
Published: May 2020

Abstract
Coronavirus disease 2019 (COVID-19) is the third coronavirus outbreak that has emerged in the past 20 years, after severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). One important aspect, highlighted by many global health organizations, is that this novel coronavirus outbreak may be especially hazardous to healthcare personnel, including laboratory professionals. Therefore, the aim of this document, prepared by the COVID-19 taskforce of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), is to provide a set of recommendations, adapted from official documents of international and national health agencies, on biosafety measures for routine clinical chemistry laboratories that operate at biosafety levels 1 (BSL-1; work with agents posing minimal threat to laboratory workers) and 2 (BSL-2; work with agents associated with human disease which pose moderate hazard). We believe that the interim measures proposed in this document for best practice will help minimazing the risk of developing COVID-19 while working in clinical laboratories.
The free group onngenerators modulon+urandom relations asngoes to infinity
Authors: Liu Yuan , Wood Melanie Matchett 
Published: May 2020

AbstractWe show that, asngoes to infinity, the free group onngenerators, modulon+u{n+u}random relations, converges to a random group that we give explicitly. This random group is a non-abelian version of the random abelian groups that feature in the Cohen–Lenstra heuristics. For eachn, these random groups belong to the few relator model in the Gromov model of random groups.
Boundary properties of fractional objects: Flexibility of linear equations
and rigidity of minimal graphs
Authors: Dipierro Serena , Savin Ovidiu , Valdinoci Enrico 
Published: May 2020

Abstract
The main goal of this article is to understand the trace properties
of nonlocal minimal graphs in

ℝ
3

{\mathbb{R}^{3}}

, i.e. nonlocal minimal surfaces with a graphical structure.
We establish that at any boundary points at which
the trace from inside happens to coincide with
the exterior datum, also the tangent planes
of the traces necessarily coincide with those of the exterior datum.
This very rigid geometric constraint is in sharp contrast with the case
of the solutions of the linear equations driven by the fractional Laplacian,
since we also show that, in this case, the fractional normal
derivative can be prescribed arbitrarily, up to a small error.
We remark that, at a formal level,
the linearization of the trace of a nonlocal minimal graph
is given by the fractional normal derivative of a fractional Laplace problem,
therefore the two problems are formally related. Nevertheless, the nonlinear equations of fractional mean curvature type
present very specific properties which are strikingly different from
those of other problems of fractional type
which are apparently similar, but
diverse in structure, and the nonlinear
case given by the nonlocal minimal graphs
turns out to be significantly more rigid than its linear counterpart.
A case of prenatal diagnosis of single umbilical artery due to thrombosis diagnosed by the ultrasound finding of “wink-sign”
Authors: Goto Minako , Nakamura Masamitsu , Arakaki Tatsuya , Takita Hiroko , Matsuoka Ryu , Sekizawa Akihiko 
Published: May 2020

Abstract

Objectives
Umbilical artery thrombosis is a significant umbilical cord condition that is associated with adverse pregnancy outcomes. However, no consensus has been reached regarding how umbilical artery thrombosis should be diagnosed or managed because of its rarity and the difficulty associated with an antenatal diagnosis.

Case presentation
Here, we describe a case involving decreased fetal movement and non-reassuring fetal status (NRFS) in which acute umbilical artery thrombosis was prenatally diagnosed. Transabdominal ultrasound showed that the cross-section of the umbilical cord had one normal artery and a small deformed echogenic area. A characteristic ultrasound finding known as the “wink sign” contributed to the prenatal diagnosis.

Conclusions
Evaluation of the umbilical cord enabled the estimation and facilitated the subsequent antenatal management.
Is ‘Global Value Chain’ a Legal Concept?
Authors: Eller Klaas Hendrik 
Published: May 2020

Abstract
Today’s organization of production and services along global value chains (GVCs) uses contracts as central building blocks, yet is largely disconnected from contract law’s dominant epistemology and social imaginary. This article charts when, how and why GVCs have appeared on the radar of contract scholars and unravels the related methodological and disciplinary challenges. Rather than treating GVCs as a ‘legal concept’ in a strict sense that might command the application of particular rules, I propose to understand them as a ‘legal heuristic’: GVCs require contract law to revisit its constitutive role for matters of distribution, participation and equality under globalization. Towards this, GVCs need to be understood as organizational arrangement and simultaneously as a stage in the evolution of a global political economy. Beyond the classical confines of ‘contract governance’, this brings into the picture the wide array of formal and informal technologies of ‘contract governmentality’. Together with the material, technological or informational infrastructure, these are referred to as ‘code’ of GVCs, suggested here as focus of future contract law research on GVCs.
Towards a Genealogy and Typology of Governance Through Contract Beyond Privity
Authors: Salminen Jaakko 
Published: May 2020

Abstract
Contracts are used to extend governance on supply chain and platform actors in ways that could not be envisaged when the foundations of current conceptualizations of contractual privity were laid down in the 19th century. This results in a stark contradiction. Firms use contracts to extend governance on actors beyond privity when it suits their interests, for example for reasons of supply-chain-wide cost-management. At the same time, law offers few means of holding a firm liable for the inadequate governance of social, environmental, cultural, and economic sustainability in its supply chain or platform eco-system. I propose two tools for uncovering the multiple societal tensions that this disjuncture between law and contractual practice entails. The first is a genealogy of how contractual paradigms have contributed to the rise of new forms of production, such as centralized mass production in the 19th century, global value chains in the 20th century, and the platform economy in the 21st century. The second is a multidisciplinary typology of the contractual mechanisms used to extend governance beyond privity. My hope is that these two tools will help us better understand, research, teach, and balance the implications of contractual paradigms on the social, environmental, cultural, and economic sustainability of production.
Regulating Contracting in Global Value Chains. Institutional Alternatives and their Implications for Transnational Contract Law
Authors: Cafaggi Fabrizio , Iamiceli Paola 
Published: May 2020

Abstract
Global Value Chains (GVCs) are both instruments to organize production and vehicles to implement transnational standards, to improve sustainability and to ensure compliance with regulatory requirements. GVCs present a very high degree of interdependence among the enterprises. GVCs are not uniform universes. Part of the production process is organized through subsidiaries of the chain leader, partly with independent suppliers linked to the chain leader by long-term and stable contractual relationships, and partly with spot contracts. Hence, different modes of contracting are needed to ensure coordination and uniformity of principles along the chain. The differences within the chain suggest that a modular approach with adaptation to the various types of relationships is more effective than a uniform approach indifferently applied both to intrafirm (subsidiaries) and inter-firm (relationships with independent suppliers) contracting.
While acknowledging the relevance of the institutional and legal framework, including the applicable law, this article focuses on the contractual structure of chain governance. We propose a modular architecture that integrates general principles of global trade in supply chains with local regulations. This approach will better combine the supplier codes, the framework agreements between parties, and the individual contracts that regulate specific exchanges.
Sustainability Clauses in an unsustainable Contract Law?
Authors: Ulfbeck Vibe , Hansen Ole 
Published: May 2020

Abstract
Companies in global value chains respond to the general sustainability agenda in society by inserting sustainability clauses into their contracts and it has been argued that there is a need to develop general contract law (default contract law rules) in order for it to be able to respond to this sustainability agenda. This article firstly examines the basis for this view and three specific areas of interest in this regard. Secondly, it draws attention to the internal tensions that will be created in the chain by on the one hand pursuing sustainability goals, external to the interests of the contracting parties, and on the other hand a consequential need to protect the supplier as the weaker party in the chain.
Carleson measure characterizations of the Campanato type space associated with Schrödinger operators on stratified Lie groups
Authors: Wang Yixin , Liu Yu , Sun Chuanhong , Li Pengtao 
Published: May 2020

Abstract
Let

ℒ
=

-

Δ
𝔾

+
V

{\mathcal{L}=-{\Delta}_{\mathbb{G}}+V}

be a Schrödinger operator on the stratified Lie group

𝔾

{\mathbb{G}}

, where

Δ
𝔾

{{\Delta}_{\mathbb{G}}}

is the sub-Laplacian and the nonnegative potential V belongs to the reverse Hölder class

B

q
0

{B_{q_{0}}}

with

q
0

>

𝒬
/
2

{q_{0}>\mathcal{Q}/2}

and

𝒬

{\mathcal{Q}}

is the homogeneous dimension of

𝔾

{\mathbb{G}}

.
In this article, by Campanato type spaces

Λ
ℒ
α

⁢

(
𝔾
)

{\Lambda^{\alpha}_{\mathcal{L}}(\mathbb{G})}

, we introduce Hardy type spaces associated with

ℒ

{\mathcal{L}}

denoted by

H
ℒ
p

⁢

(
𝔾
)

{H^{{p}}_{\vphantom{\varepsilon}{\mathcal{L}}}(\mathbb{G})}

and prove the atomic characterization of

H
ℒ
p

⁢

(
𝔾
)

{H^{{p}}_{\vphantom{\varepsilon}{\mathcal{L}}}(\mathbb{G})}

.
Further, we obtain the following duality relation:

Λ
ℒ

𝒬
⁢

(

1
/
p

-
1

)

⁢

(
𝔾
)

=

(

H
ℒ
p

⁢

(
𝔾
)

)

∗

,

𝒬
/

(

𝒬
+
δ

)

<
p
<
1

for

⁢
δ

=

min
⁡

{
1
,

2
-

𝒬
/

q
0

}

.

\Lambda_{\mathcal{L}}^{\mathcal{Q}(1/p-1)}(\mathbb{G})=(H^{{p}}_{\vphantom{%
\varepsilon}{\mathcal{L}}}(\mathbb{G}))^{\ast},\quad\mathcal{Q}/(\mathcal{Q}+%
\delta)<p<1\quad\text{for}\ \delta=\min\{1,2-\mathcal{Q}/q_{0}\}.

The above relation enables us to characterize

Λ
ℒ
α

⁢

(
𝔾
)

{\Lambda^{\alpha}_{\mathcal{L}}(\mathbb{G})}

via two families of Carleson measures generated by the heat semigroup and the Poisson semigroup, respectively.
Also, we obtain two classes of perturbation formulas associated with the semigroups related to

ℒ

{\mathcal{L}}

.
As applications, we obtain the boundedness of the Littlewood–Paley function and the Lusin area function on

Λ
ℒ
α

⁢

(
𝔾
)

{\Lambda^{\alpha}_{\mathcal{L}}(\mathbb{G})}

.