bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficiency analysis for quantitative MRI of T1 and T2 relaxometry methods
Authors: Leitão David , Teixeira Rui Pedro A. G. , Price Anthony , Uus Alena , Hajnal Joseph V. , Malik Shaihan J. 
Published: June 2021

Abstract
This study presents a comparison of quantitative MRI methods based on an efficiency metric that quantifies their intrinsic ability to extract information about tissue parameters. Under a regime of unbiased parameter estimates, an intrinsic efficiency metric

η

was derived for fully-sampled experiments which can be used to both optimize and compare sequences. Here we optimize and compare several steady-state and transient gradient-echo based qMRI methods, such as magnetic resonance fingerprinting (MRF), for joint

T
1

and

T
2

mapping. The impact of undersampling was also evaluated, assuming incoherent aliasing that is treated as noise by parameter estimation. In vivo validation of the efficiency metric was also performed. Transient methods such as MRF can be up to 3.5 times more efficient than steady-state methods, when spatial undersampling is ignored. If incoherent aliasing is treated as noise during least-squares parameter estimation, the efficiency is reduced in proportion to the SNR of the data, with reduction factors of 5 often seen for practical SNR levels. In vivo validation showed a very good agreement between the theoretical and experimentally predicted efficiency. This work presents and validates an efficiency metric to optimize and compare the performance of qMRI methods. Transient methods were found to be intrinsically more efficient than steady-state methods, however the effect of spatial undersampling can significantly erode this advantage.
When quantum state tomography benefits from willful ignorance
Authors: Motka Libor , Paúr Martin , Řeháček Jaroslav , Hradil Zdeněk , Sánchez-Soto Luis L 
Published: June 2021

Abstract
We show that quantum state tomography with perfect knowledge of the measurement apparatus proves to be, in some instances, inferior to strategies discarding all information about the measurement at hand, as in the case of data pattern tomography. In those scenarios, the larger uncertainty about the measurement is traded for the smaller uncertainty about the reconstructed signal. This effect is more pronounced for minimal or nearly minimal informationally complete measurement settings, which are of utmost practical importance.
The Automatic Observation Management System of the GWAC Network. I. System Architecture and Workflow
Authors: Han Xuhui , Xiao Yujie , Zhang PinPin , Turpin Damien , Xin Liping , Wu Chao , Cai Hongbo , Dong Wenlong , Huang Lei , Kang Zhe , Leroy Nicolas , Li Huali , Li Zhenwei , Lu Xiaomeng , Qiu Yulei , Stahl Benjamin E. , Wang Jing , Wang Xianggao , Xu Yang , Yang Yuangui , Zhao Yong , Zhang Ruosong , Zheng Weikang , Zheng Yatong , Wei Jianyan 
Published: June 2021

Abstract
The Ground Wide Angle Camera Network (GWAC-N) is a network of robotic multi-aperture, multiple field-of-view (FoV) optical telescopes. The main contingent of GWAC-N instruments are provided by the Ground Wide Angle Cameras Array (GWAC-A), and additional, narrower FoV telescopes are utilized to provide fast multi-band follow-up capabilities. The primary scientific goal of the GWAC-N is to search for optical counterparts of gamma-ray bursts that will be detected by the Space Variable Object Monitor (SVOM) satellite. The GWAC-N performs many additional observing tasks including follow-up of Target of Opportunities (ToO) targets and the detection (and monitoring) of variable objects and optical transients. To handle these use cases (and to allow for extensibility), we have designed ten observation modes and 175 observation strategies, including a joint strategy with multiple GWAC-N telescopes for the follow-up of gravitational wave (GW) events. To perform these observations, we develop an Automatic Observation Management (AOM) system capable of performing object management, dynamic scheduling, automatic broadcasting across the network, and image handling. The AOM system combines the individual telescopes which comprise the GWAC-N into a network and smoothly organizes all associated operations, completely meeting the requirements dictated by GWAC-N. With its modular design, the AOM is scientifically and technically viable for other general-purpose telescope networks. As the GWAC-N extends and evolves, the AOM will greatly enhance its discovery potential. In this first paper of a series, we present the scientific goals of the GWAC-N and detail the hardware, software, and workflow developed to achieve these goals. The structure, technical design, implementation, and performance of the AOM system are also described in detail. We conclude with a summary of the current status of the GWAC-N and our near-future development plan.
Finite element analysis of two-way hollow core reinforced concrete slab under punching repeated load
Authors: Tameemi Waleed A , Alwash Nameer A 
Published: June 2021

Abstract
This research provides informationabout the finite element analysis of the structural behavior of an innovative new type of two-wayhollow reinforced concrete (RC) slabs of two-way plastic piping system under the effects of concentratedpunching repeated loads. This new type of two-way hollow slab could be constructedbyreplacing part of the concrete volume by a continuous network of two-way plastic piping systemsto cutportion of the dead loads by reducing the self-weight of the createdslabsas well as offering networks of voids inside the RC slab which could be valuable for passing utility lines. The reliability of elements forms, material characteristics, types of constantsand the convergence study of the proposed finite element model of the new type of two-way hollow RC slabswas confirmed by the outcomes of the numerical study and the experimental results using five different parametric studies. The proposed FE modeshowed satisfactoryaccuracy with a maximum varianceratio of about 0.11in comparison with the ultimate loading capacity of the experimental behavior. The results weredemonstratingthe efficiency of the new methodology of producing two-way hollow RC slabs using the two-way piping system by reducing the self-weight by about 24% with maintaining about 79% of the total strength. Moreover, the reduction in the strength could be eliminated by locating the networks of plastic pipes out of the locations of the maximum stresses, adding micro steel fiber, using high strength concrete or increasing the reinforcement ratio.
Review on Bond Strength of Recycled Aggregates in Concrete
Authors: Ramasamy Krishnaraja Ammapalayam , Sadasivam Yuvarani , Rajaram Vishnu , Nithiyananthan Yogesh , Anandaraj S , Harihanandh M 
Published: June 2021

Abstract
Many buildings have either reached the end of their lifespan or were designed without meeting the requirements. Large quantities of concrete debris result from the demolition or repair work in such buildings can be reused. The use of reused aggregate concrete to replace the aggregates in conventional concrete will help to alleviate the aggregate shortages. By reusing the construction waste materials, we can reduce the waste generation and also can conserve the environment. Many researchers had proved that the strength of the recycled aggregate concretes (RAC) is similar to that of conventional concretes. The main aim of this review is to study the concrete strength prepared with the reused coarse aggregate concrete relating to the bond strength, compressive strength and tensile strength by replacement level and also by adding chemical admixtures.
The evolution of LPSO phase and its influence on grain size during cooling free forging
Authors: Wang Guoqiang , Xiao Zhongliang , Yang Zhen , Liu Pengzhan 
Published: June 2021

Abstract
In this paper, the deformation behavior of the LPSO phase of Mg-Gd-Y-Zn-Zr and its influence on the grain size are studied during the cooling free forging deformation. Studies have shown that cooling free forging can refine different forms of LPSO phases. The lamellar and block LPSO phases are kinked and broken during the deformation process. The kink angle and the number of kinks of the lamellar phase are greater than that of the block phase. With the increase of the cooling pass, the fragmentation of the lamellar phase is more violent. The kink and broken of the LPSO phase significantly refined the grain size by dividing the grains and promoting dynamic recrystallization. The grain size has dropped significantly from 113 μm in one pass to 12 μm in three passes. Uniform fine structure improves alloy mechanical properties through the Hall-Petch principle. The ultimate tensile strength of three-pass alloy reaches 323.2 MPa, the yield strength reaches 239.9 MPa, and the elongation reaches 17.1%.
Direct detectors and their applications in electron microscopy for materials science
Authors: Levin Barnaby D A 
Published: June 2021

Abstract
The past decade has seen rapid advances in direct detector technology for electron microscopy. Direct detectors are now having an impact on a number of techniques in transmission electron microscopy (TEM), scanning electron microscopy, and scanning TEM (STEM), including single particle cryogenic electron microscopy, in situ TEM, electron backscatter diffraction, four-dimensional STEM, and electron energy loss spectroscopy. This article is intended to serve as an introduction to direct detector technology and an overview of the range of electron microscopy techniques that direct detectors are now being applied to.
Persistence of Disparities Among Racially/Ethnically Marginalized Groups in the Coronavirus Disease 2019 Pandemic Regardless of Statewide Shelter-in-Place Policies: An Analysis From Northern California
Authors: Azar Kristen M J , Lockhart Stephen H , Shen Zijun , Romanelli Robert , Brown Stephanie , Smits Kelly , Pressman Alice R 
Published: June 2021

Abstract
To measure disparities in coronavirus disease 2019 (COVID-19) hospitalization and intensive care unit (ICU) transfer among racially/ethnically marginalized groups before and after implementation of the California statewide shelter-in-place (SIP) policy, we conducted a retrospective cohort study within a health-care system in California. COVID-19 patients diagnosed from January 1, 2020, to August 31, 2020, were identified from electronic health records. We examined hospitalizations and ICU transfers by race/ethnicity and pandemic period using logistic regression. Among 16,520 people with COVID-19 (mean age = 46.6 (standard deviation, 18.4) years; 54.2% women), during the post-SIP period, patients were on average younger and a larger proportion were Hispanic. In adjusted models, odds of hospitalization were 20% lower post-SIP as compared with the SIP period, yet all non-White groups had higher odds (odds ratios = 1.6–2.1) than non-Hispanic White individuals, regardless of period. Among hospitalized patients, odds of ICU transfer were 33% lower post-SIP than during SIP. Hispanic and Asian patients had higher odds than non-Hispanics. Disparities in hospitalization persisted and ICU risk became more pronounced for Asian and Hispanic patients post-SIP. Policy-makers should consider ways to proactively address racial/ethnic inequities in risk when considering future population-level policy interventions for public health crises.
A bee’s eye view of remarkable floral colour patterns in the south-west Australian biodiversity hotspot revealed by false colour photography
Authors: Lunau Klaus , Scaccabarozzi Daniela , Willing Larissa , Dixon Kingsley 
Published: June 2021

AbstractBackground and AimsColour pattern is a key cue of bee attraction selectively driving the appeal of pollinators. It comprises the main colour of the flower with extra fine patterns, indicating a reward focal point such as nectar, nectaries, pollen, stamens and floral guides. Such advertising of floral traits guides visitation by the insects, ensuring precision in pollen gathering and deposition. The study, focused in the Southwest Australian Floristic Region, aimed to spot bee colour patterns that are usual and unusual, missing, accomplished by mimicry of pollen and anthers, and overlapping between mimic-model species in floral mimicry cases.MethodsFloral colour patterns were examined by false colour photography in 55 flower species of multiple highly diverse natural plant communities in south-west Australia. False colour photography is a method to transform a UV photograph and a colour photograph into a false colour photograph based on the trichromatic vision of bees. This method is particularly effective for rapid screening of large numbers of flowers for the presence of fine-scale bee-sensitive structures and surface roughness that are not detectable using standard spectrophotometry.Key ResultsBee- and bird-pollinated flowers showed the expected but also some remarkable and unusual previously undetected floral colour pattern syndromes. Typical colour patterns include cases of pollen and flower mimicry and UV-absorbing targets. Among the atypical floral colour patterns are unusual white and UV-reflecting flowers of bee-pollinated plants, bicoloured floral guides, consistently occurring in Fabaceae spp., and flowers displaying a selective attractiveness to birds only. In the orchid genera (Diuris and Thelymitra) that employ floral mimicry of model species, we revealed a surprising mimicry phenomenon of anthers mimicked in turn by model species.ConclusionThe study demonstrates the applicability of ‘bee view’ colour imaging for deciphering pollinator cues in a biodiverse flora with potential to be applied to other eco regions. The technique provides an exciting opportunity for indexing floral traits on a biome scale to establish pollination drivers of ecological and evolutionary relevance.
Identification of dipyrrolone pigments and their precursors formed in the Maillard reaction of carnosine and pentose under weakly acidic conditions
Authors: Nomi Yuri , Yamazaki Kento , Mori Yuki , Matsumoto Hitoshi , Sato Shinji 
Published: June 2021

ABSTRACT
Colored compounds formed by the Maillard reaction of carnosine with xylose or glucose were investigated in this study. Yellow pigments showing an absorption maximum at 450 nm were found in a heated solution of carnosine with xylose at pH 5.0. These pigments were then isolated and identified as dicarnosyl-dipyrrolones A and B. The generation of dipyrrolones in the absence of lysine suggests that dipyrrolone pigments can be formed by pentose as well as every amino compound such as amino acids, peptides and proteins possessing a free amino group. Analysis of α-dicarbonyls using LC-MS/MS showed that pentosone, 1-deoxypentosone, 3-deoxypentosone (3-DP), and methylglyoxal were predominantly generated via degradation of Amadori compounds. Also, a potential formation pathway of dypyrrolones was established, indicating that an Amadori compound that could form 3-DP is likely to play a role as a main precursor for dipyrrolones.
When perception isn’t reality: allometric variation in the exaggerated mandibles of male stag beetles (Coleoptera: Lucanidae)
Authors: Packard Gary C 
Published: June 2021

AbstractA variety of protocols have been used to study allometric variation in size of the exaggerated mandibles on male stag beetles. Many of these protocols entail logarithmic transformation of the original measurements followed by numerical analysis of the transformations by linear regression or some conceptual extension thereof. I reanalysed data from four such studies to show how these protocols can lead investigators to conclusions that are not well supported by the original observations. One of the data sets was originally reported to conform to simple loglinear allometry, with untransformed observations that presumably follow the path of a two-parameter power function; one was said to represent biphasic, loglinear allometry, with two distinctive morphs having different scaling relationships on the arithmetic scale; and two were originally described as cases of discontinuous, loglinear allometry caused by dimorphisms. My analyses, which were based on graphical analysis and nonlinear regression of untransformed observations, revealed that all the data sets form S-shaped distributions and that each of the distributions is well described by a four-parameter sigmoid function. None of the bivariate distributions reveals a discontinuity or dimorphism. Thus, the original authors unknowingly offered descriptions and interpretations for patterns of variation that do not exist in their data.
Declining common toad body size correlated with climate warming
Authors: Reading Christopher J , Jofré Gabriela M 
Published: June 2021

Abstract
Accumulating evidence shows that the body size of organisms in many taxa is declining in response to global warming. We investigated the potential effect of rising temperatures on the body size of a common toad (Bufo bufo L.) population in southern England between 1983 and 2020. The body length (SVL; in millimetres) and body mass (in grams) of 15 550 males and 4004 females arriving at their breeding pond for the first time were recorded. Toad body condition was estimated using a scaled body mass index (SMI). Over the study period, the mean annual temperature increased by ~1.3 °C, whereas the mean SVL and SMI of both sexes declined. Multiple regression analysis showed that female and male SMI were negatively correlated with increases in mean summer temperatures, with females also being impacted minimally by mean winter rainfall. Mean body size (SVL) was positively correlated with toad abundance over the period between emergence as toadlets and arrival at the pond to breed for the first time. Common toads exhibited phenotypic plasticity in response to warming environmental conditions, resulting in a reduction in SMI and subsequent reductions in SVL and overall egg production, which occurred over a period of 10 years.
Effect of Viral Replication and Liver Fibrosis on All-Cause Mortality in Human Immunodeficiency Virus–Hepatitis B Virus–Coinfected Individuals: A Retrospective Analysis of a 15-Year Longitudinal Cohort
Authors: Dezanet Lorenza N C , Kassime Raisha , Miailhes Patrick , Lascoux-Combe Caroline , Chas Julie , Maylin Sarah , Gabassi Audrey , Rougier Hayette , Delaugerre Constance , Lacombe Karine , Boyd Anders 
Published: June 2021

Abstract

Background
In individuals living with human immunodeficiency virus (HIV) and hepatitis B virus (HBV), widespread tenofovir (TDF)–containing antiretroviral therapy (ART) has led to substantial decreases in HBV-DNA and HIV-RNA detection. However, the links between viral replication, liver fibrosis, and mortality remain unclear.

Methods
A total of 300 individuals living with HIV-HBV and undergoing ART were prospectively followed. Virological and clinical data were obtained at baseline and every 6–12 months. We quantified the associations between HBV-DNA, HIV-RNA, and liver fibrosis with risk of all-cause mortality using a joint longitudinal survival model. Viral detection, viral loads, and time-averaged cumulative viral loads of HIV and HBV were modeled as 3 separate exposures.

Results
During a median of 10.5 years (interquartile range, 4.0–14.6), the proportion undergoing TDF-containing ART (baseline = 18.7%, end of follow-up = 79.1%) and with undetectable HBV-DNA (baseline = 36.7%, end of follow-up = 94.8%) substantially increased. 42 participants died (incidence rate = 1.30/100 person-years, 95% confidence interval [CI] = .96–1.76). The leading causes of death were non-AIDS/non–liver-related malignancies (28.6%), followed by liver-related (16.7%), AIDS-related (16.7%), and other (16.7%). All-cause mortality was associated with HBV-DNA viral load (adjusted hazards ratio [aHR] per log10 IU/mL = 1.41, 95% CI = 1.04–1.93, P = .03) or time-averaged cumulative HBV-DNA (aHR per log10 copy-years = 1.37, 95% CI = 1.03–1.83, P = .03), but not undetectable HBV-DNA. Advanced liver fibrosis at baseline was also associated with increased mortality rates (aHR = 2.35, 95% CI = 1.16–4.76, P = .02). No significant association between HIV-RNA replication and mortality was observed.

Conclusions
Concurrent and historical HBV replication and liver fibrosis are important drivers of all-cause mortality in largely TDF-treated individuals living with HIV-HBV, despite one-fifth of deaths being liver-related. HBV-DNA and liver fibrosis remain important prognostic indicators for this patient population.
Spike and neutralizing antibodies response to COVID-19 vaccination in haemodialysis patients
Authors: Giot Matthieu , Fourié Toscane , Lano Guillaume , Villarroel Paola Mariela Saba , Lamballeri Xavier de , Gully Marion , Samson Laurent , Farault Julien , Bouchouareb Dammar , Jehel Océane , Brunet Philippe , Jourde-Chiche Noémie , Ninove Laetitia , Robert Thomas 
Published: June 2021

Abstract

Background
Humoral response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines needs to be evaluated in the fragile population of patients on maintenance haemodialysis (HD).

Methods
We analysed the antibody response to the spike (S) antigen of SARS-CoV-2 before and after each dose of the messenger RNA (mRNA) Comirnaty vaccine (BNT162b2; BioNTech & Pfizer) in patients from a single dialysis centre and detected the presence of neutralizing antibodies (Nabs).

Results
Among the 90 vaccinated HD patients (mean age 69 years, 61% male), 19 (21%) had a history of SARS-CoV-2 infection. A seroconversion with anti-S immunoglobulin G antibodies (Sabs) was documented in 20% of patients after the first dose (early responders) and in 77% after the second dose, while 23% were non-responders. Cardiac disease, cirrhosis and gamma globulin levels were independently predictive of the absence of seroconversion. Nabs were detected in 15.4% of early responders after the first dose and in 84.6% of early responders and 57.9% of late responders after the second dose. Sab titres after the second dose were higher in patients with Nab than without Nab {598 [interquartile range (IQR) 246–882]) versus 134 [IQR 61–390]; P &lt; 0.0001}. All patients with a history of SARS-CoV-2 infection developed both Sabs and Nabs and their titres for Sabs and Nabs were higher than in late responders.

Conclusions
Most HD patients develop a substantial humoral response against SARS-CoV2, with Nabs, following the mRNA vaccine. Whether this immunity persists over time and is able to efficiently protect patients from coronavirus disease 2019 remains to be determined.