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The transport phenomena of Casson nanofluid flow between two parallel disks subject to convective boundary conditions are analyzed in this paper. The mathematical model incorporates the impact of thermophoresis and Brownian motion since the Buongiorno's nanoliquid model is adopted to characterize the nanoliquid's transport features. The appropriate similarity transformations are applied to obtain the resulting nondimensional ordinary differential equations from the basic governing equations. The resulting ordinary differential equations and the associated boundary conditions are solved analytically by adopting the homotopy perturbation technique. Further, a statistical experiment is conducted to identify notable flow parameters which cause significant impact on the heat transfer rate. The characteristics of critical pertinent parameters on the flow field are graphically manifested. It is worth noting that the Casson nanofluid velocity escalates by augmenting the magnetic field parameter in the case of injection near the disks. Nanoparticle concentration is considerably diminished with an increment in thermophoresis parameter. In the cases of equal and unequal Biot numbers, the heat transfer rate is promoted with higher values of the Brownian motion parameter. Among the Casson fluid parameter, squeezing parameter and magnetic field parameter, the heat transfer rate discloses the highest positive sensitivity with the lowest value of the Casson fluid parameter. [ABSTRACT FROM AUTHOR]

Objective: To compare the diagnostic performance of different manufacturers' immunoassays for the soluble fms‐like tyrosine kinase‐1 (sFlt‐1)‐to‐placental growth factor (PlGF) ratio with that of a point‐of‐care (PoC) test for glycosylated fibronectin (GlyFn) in women with suspected pre‐eclampsia (PE). Methods: This was a prospective, single‐center, double‐blinded, non‐interventional study of East Asian women with a singleton pregnancy who presented with hypertension with or without clinical features of PE after 20 weeks' gestation between January 2020 and March 2022. Maternal serum samples were collected at the time of presentation, and subsequent management followed the departmental protocol, based on gestational age, severity of hypertension, fetal condition and presence of severe PE features. Women diagnosed with PE at presentation were excluded. PE was diagnosed according to the 2018 International Society for the Study of Hypertension in Pregnancy classification. Levels of sFlt‐1 and PlGF were measured using the Cobas e411 (Roche Diagnostics), BRAHMS KRYPTOR (ThermoFisher Scientific) and iMAGIN 1800 (Ningbo Aucheer) platforms. GlyFn levels were measured using the Lumella™ GlyFn PoC test (DiabetOmics Inc.). The predictive performance of each test to rule out PE within 7 days and rule in PE within 28 days from the date of presentation was assessed. Based on the PROGNOSIS study, a sFlt‐1/PlGF ratio of ≤ 38 on the Roche platform was used to predict the absence of PE within 7 days. The sFlt‐1/PlGF ratio was classified as high or low using platform‐specific thresholds equivalent to a Roche sFlt‐1/PlGF ratio of 38, which were derived using Passing–Bablok regression. GlyFn was categorized as high or low using two reported clinical management thresholds (263 μg/mL and 510 μg/mL). Results: Overall, 236 women with suspected PE were included, of whom 70 (29.7%) were diagnosed with PE; 36 (51.4%) and 70 (100%) developed PE within 7 days and 28 days, respectively. Eighty‐eight (37.3%) women had a sFlt‐1/PlGF ratio of > 38 on the Roche platform, 79 (33.5%) women had a sFlt‐1/PlGF ratio of > 55 on the KRYPTOR platform and 96 (40.7%) women had a sFlt‐1/PlGF ratio of > 40 on the iMAGIN 1800 platform. Furthermore, 62 (26.3%) and four (1.7%) women had a GlyFn level of > 263 μg/mL and > 510 μg/mL, respectively. The negative predictive value (NPV) of the sFlt‐1/PlGF ratio measured on the Roche, KRYPTOR and iMAGIN 1800 platforms to rule out PE within 7 days after presentation was 83.3%, 82.0% and 82.9%, respectively, while that for GlyFn > 263 μg/mL and > 510 μg/mL was 82.6% and 70.4%, respectively. The corresponding positive predictive values (PPV) to rule in PE within 28 days after presentation were 50.5%, 52.3% and 46.7%, respectively, for the sFlt‐1/PlGF ratio, and 35.4% and 50.0%, respectively, for GlyFn > 263 μg/mL and > 510 μg/mL. Conclusions: The predictive performance of different manufacturers' assays for the sFlt‐1/PlGF ratio to rule in and rule out PE were similar once standardized to a common threshold. Our findings suggest that the sFlt‐1/PlGF ratio and GlyFn using a cut‐off of 263 μg/mL can both be utilized to rule out PE within 7 days after assessment, with a moderate NPV. The PPV for ruling in PE within 28 days remains poor. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

We report ultra-deep, medium-resolution spectroscopic observations for four quiescent galaxies with log |$_{10}(M_*/\mathrm{M_\odot })\gt 11$| at |$3 \lt z \lt 5$|⁠. These data were obtained with JWST NIRSpec as part of the Early eXtragalactic Continuum and Emission Line Science (EXCELS) survey, which we introduce in this work. The first two galaxies are newly selected from PRIMER UDS imaging, both at |$z=4.62$| and separated by 860 pkpc on the sky, within a larger structure for which we confirm several other members. Both formed at |$z\simeq 8-10$|⁠. These systems could plausibly merge by the present day to produce a local massive elliptical galaxy. The other two ultra-massive quiescent galaxies are previously known at |$z=3.99$| and 3.19, with the latter (ZF-UDS-7329) having been the subject of debate as potentially too old and too massive to be accommodated by the |$\Lambda$| -CDM halo-mass function. Both exhibit high stellar metallicities, and for ZF-UDS-7329 we are able to measure the |$\alpha -$| enhancement, obtaining [Mg/Fe] = |$0.42^{+0.19}_{-0.17}$|⁠. We finally evaluate whether these four galaxies are consistent with the |$\Lambda$| -CDM halo-mass function using an extreme value statistics approach. We find that the |$z=4.62$| objects and the |$z=3.19$| object are unlikely within our area under the assumption of standard stellar fractions (⁠|$f_*\simeq 0.1-0.2$|⁠). However, these objects roughly align with the most massive galaxies expected under the assumption of 100 per cent conversion of baryons to stars (⁠|$f_*$| =1). Our results suggest extreme galaxy formation physics during the first billion years, but no conflict with |$\Lambda$| -CDM cosmology. [ABSTRACT FROM AUTHOR]

In this paper we prove that an interesting combinatorial inequality holds true. The importance of this inequality is due to its implication on settling a conjecture on structure of maximal commutative subalgebras of Grassmann algebra, posted by Domokos and Zubor in 2015. [ABSTRACT FROM AUTHOR]

In this paper, we derive new summation identities involving the (products of) Fibonacci quaternions by the method of summation-by-parts. We apply our method to derive summation identities which involve the (products of) hyperFibonacci quaternions. By using the method of generating functions, we derive convolution-sum identities for the Fibonacci quaternions. Finally, we derive binomial-sum identities for the Fibonacci quaternions by matrix method. [ABSTRACT FROM AUTHOR]

In this paper we find closed forms for certain finite sums. In each case, the denominator of the summand consists of products of two distinct Fibonacci numbers. We express each closed form in terms of reciprocals of the Fibonacci numbers. The results are also generalized to Fibonacci polynomials and Lucas polynomials. [ABSTRACT FROM AUTHOR]

Introduction: A substantial number of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain asymptomatic throughout the course of infection. Nearly half of pregnant women with coronavirus disease 2019 (COVID-19) are asymptomatic upon diagnosis; these cases are not without risk of maternal morbidity. Here, we investigated the seroprevalence of anti-SARS-CoV-2 antibodies in an unselected sample of pregnant women in Hong Kong., Methods: This prospective cohort study included pregnant women who presented for routine Down syndrome screening (DSS) between November 2019 and October 2020; all women subsequently delivered at the booking hospitals. Serum antibodies against SARS-CoV-2 were analysed using a qualitative serological assay in paired serum samples taken at DSS and delivery for all participants., Results: In total, 1830 women were recruited. Six women (0.33%) were seropositive at the DSS visit; this seropositivity persisted until delivery. Of the six women, none reported relevant symptoms during pregnancy; one reported a travel history before DSS and one reported relevant contact history. The interval between sample collections was 177 days (range, 161-195). Among women with epidemiological risk factors, 1.79% with travel history, 50% with relevant contact history, and 0.77% with community SARS-CoV-2 testing history, were seropositive., Conclusion: The low seroprevalence in this study suggests that strict public health measures are effective for preventing SARS-CoV-2 transmission. However, these measures cannot be maintained indefinitely. Until a highly effective therapeutic drug targeting SARS-CoV-2 becomes available, vaccination remains the best method to control the COVID-19 pandemic., Competing Interests: LCY Poon has received speaker fees and consultancy payments from Roche Diagnostics and Ferring Pharmaceuticals. She has also received in-kind contributions from Roche Diagnostics. Other authors have disclosed no conflict of interest.