Rubber, raw natural. Colour index test

AbstractDifferential diagnosis of parkinsonian syndromes is considered one of the most challenging in neurology. Quantitative MR planimetric measurements were reported to discriminate between progressive supranuclear palsy (PSP) and non-PSP-parkinsonism. Several studies have used midbrain to pons ratio (M/P) and the Magnetic Resonance Parkinsonism Index (MRPI) in distinguishing PSP patients from those with Parkinson's disease. The current meta-analysis aimed to compare the performance of these measures in discriminating PSP from multiple system atrophy (MSA). A systematic MEDLINE review identified 59 out of 2984 studies allowing a calculation of sensitivity and specificity using the MRPI or M/P. Meta-analyses of results were carried out using random effects modelling. To assess study quality and risk of bias, the QUADAS-2 tool was used. Eight studies were suitable for analysis. The meta‐analysis showed a pooled sensitivity and specificity for the MRPI of PSP versus MSA of 79.2% (95% CI 72.7–84.4%) and 91.2% (95% CI 79.5–96.5%), and 84.1% (95% CI 77.2–89.2%) and 89.2% (95% CI 81.8–93.8%), respectively, for the M/P. The QUADAS-2 toolbox revealed a high risk of bias regarding the methodological quality of patient selection and index test, as all patients were seen in a specialized outpatient department without avoiding case control design and no predefined threshold was given regarding MRPI or M/P cut-offs. Planimetric brainstem measurements, in special the MRPI and M/P, yield high diagnostic accuracy for the discrimination of PSP from MSA. However, there is an urgent need for well-designed, prospective validation studies to ameliorate the concerns regarding the risk of bias.

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Consistency and mechanical properties of sustainable concrete blended with brick dust waste cementitious materials

SN Applied Sciences ◽

10.1007/s42452-021-04430-w ◽

2021 ◽

Vol 3 (4) ◽

Author(s):

S. Y. Amakye ◽

S. J. Abbey ◽

A. O. Olubanwo

Keyword(s):

Tensile Strength ◽

Fresh Concrete ◽

Environmental Benefits ◽

Partial Replacement ◽

Target Range ◽

Hardened Concrete ◽

Index Test ◽

Demolition Waste ◽

Concrete Mix ◽

Brick Dust

AbstractThe reuse of waste materials in civil engineering projects has become the topic for many researchers due to their economic and environmental benefits. In this study, brick dust waste (BDW) derived from cutting of masonry bricks and demolition waste which are normally dumped as land fill is used as partial replacement of cement in a concrete mix at 10%, 20% and 30% respectively, with the aim of achieving high strength in concrete using less cement due to the environmental problems associated with the cement production. To ascertain the effects of BDW on the consistency and mechanical performance of concrete mix, laboratory investigations on the workability of fresh concrete and the strength of hardened concrete were carried out. Slump and compaction index test were carried out on fresh concrete mix and unconfined compressive strength (UCS) test and tensile strength test were conducted on hardened concrete specimen after 7, 14 and 28 days of curing. The results showed high UCS and tensile strength with the addition of 10% BDW to the concrete mix, hence achieving the set target in accordance with the relevant British standards. A gradual reduction in strength was observed as BDW content increases, however, recording good workability as slump and compaction index results fell within the set target range in accordance with relevant British standards. Findings from this study concluded that BDW can partially replace cement in a concrete mix to up to 30% igniting the path to a cleaner production of novel concrete using BDW in construction work.

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Reliability and validity of an adapted hip abductor strength measure as a potential new fall risk assessment for older persons: a study protocol

BMC Geriatrics ◽

10.1186/s12877-021-02048-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Simone Chantal Gafner ◽

Caroline Henrice Germaine Bastiaenen ◽

Emmanuel Biver ◽

Serge Ferrari ◽

Lara Allet

Keyword(s):

Fall Risk ◽

Reliability And Validity ◽

Criterion Validity ◽

Risk Assessments ◽

Index Test ◽

Timed Up And Go ◽

External Criterion ◽

Closed Chain ◽

Hip Abductor ◽

Abductor Strength

Abstract Background Persons aged ≥ 65 years are currently the world’s fastest growing age group. An important complication of age is the increasing risk of falls. Falls have multifactorial etiology and modifiable risk factors open for interventions in prevention and rehabilitation, are of high interest. In this context, strong hip abductors seem to be important to prevent falls. A newly adapted measurement device to measure hip abductor strength (HAS) in a closed chain position was developed. We aim to assess feasibility, intra- and inter-tester reliability and construct and criterion validity of the new measure. Methods In two subsequent parts a feasibility, reliability and validity study with an adapted measurement instrument for the assessment of HAS (index test) in a closed chain position in persons aged ≥ 65 years will be conducted. Part I investigates feasibility of the measure in clinical settings as well as reliability of the new HAS test (n = 26). Part II evaluates construct and criterion validity (n = 169). Construct validity will be assessed cross-sectional, criterion validity by comparison with prospectively followed up fall history for 12 months (external criterion) and other functional fall risk assessments (Short Physical Performance Battery, Timed Up and Go test, usual gait speed and hand grip strength). Discussion Results of feasibility, will give insight in its applicability in daily clinical life and clinimetric properties will show if measurements of HAS in a closed chain position should be encouraged to include in fall risk assessments in older adults.

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A Comparative Study of Energy Efficiency in Tumbling Mills with the Use of Relo Grinding Media

Metals ◽

10.3390/met11050735 ◽

2021 ◽

Vol 11 (5) ◽

pp. 735

Author(s):

Nikolay Kolev ◽

Petar Bodurov ◽

Vassil Genchev ◽

Ben Simpson ◽

Manuel G. Melero ◽

...

Keyword(s):

Energy Efficiency ◽

Test Procedure ◽

Mining Industry ◽

Slight Modification ◽

Index Test ◽

Grinding Media ◽

Work Index ◽

Mineral Sample ◽

Tumbling Mills ◽

Bond Tests

An evaluation of Relo grinding media (RGM, Reuleaux tetrahedron-shaped bodies) performance versus standard grinding media (balls) was made through a series of grinding tests, including a slight modification of the standard Bond test procedure. Standard Bond tests showed a reduction in the Bond ball mill work index (wi) of the mineral sample used in this study when using Relo grinding media. The modified Bond test procedure is based on using the standard Bond ball work index test but changing the circulating loads (350%, 250%, 150%, 100%). The comparative tests with RGM were carried out at the same number of revolutions as the grinding tests with balls at respective circulating load. The RGM charge yielded a 14% higher net undersize product than balls, which hints at improving energy efficiency and the potential for significant mining industry benefits.

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Non-Invasive Biomarkers for Earlier Detection of Pancreatic Cancer—A Comprehensive Review

Cancers ◽

10.3390/cancers13112722 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2722

Author(s):

Greta Brezgyte ◽

Vinay Shah ◽

Daria Jach ◽

Tatjana Crnogorac-Jurcevic

Keyword(s):

Clinical Setting ◽

Selection Index ◽

Reporting Quality ◽

Standard Of Care ◽

Therapeutic Interventions ◽

Ductal Adenocarcinoma ◽

Index Test ◽

Delayed Presentation ◽

Non Invasive ◽

Study Selection

Pancreatic ductal adenocarcinoma (PDAC) carries a deadly diagnosis, due in large part to delayed presentation when the disease is already at an advanced stage. CA19-9 is currently the most commonly utilized biomarker for PDAC; however, it lacks the necessary accuracy to detect precursor lesions or stage I PDAC. Novel biomarkers that could detect this malignancy with improved sensitivity (SN) and specificity (SP) would likely result in more curative resections and more effective therapeutic interventions, changing thus the present dismal survival figures. The aim of this study was to systematically and comprehensively review the scientific literature on non-invasive biomarkers in biofluids such as blood, urine and saliva that were attempting earlier PDAC detection. The search performed covered a period of 10 years (January 2010—August 2020). Data were extracted using keywords search in the three databases: MEDLINE, Web of Science and Embase. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was applied for study selection based on establishing the risk of bias and applicability concerns in Patient Selection, Index test (biomarker assay) and Reference Standard (standard-of-care diagnostic test). Out of initially over 4000 published reports, 49 relevant studies were selected and reviewed in more detail. In addition, we discuss the present challenges and complexities in the path of translating the discovered biomarkers into the clinical setting. Our systematic review highlighted several promising biomarkers that could, either alone or in combination with CA19-9, potentially improve earlier detection of PDAC. Overall, reviewed biomarker studies should aim to improve methodological and reporting quality, and novel candidate biomarkers should be investigated further in order to demonstrate their clinical usefulness. However, challenges and complexities in the path of translating the discovered biomarkers from the research laboratory to the clinical setting remain and would have to be addressed before a more realistic breakthrough in earlier detection of PDAC is achieved.

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