bluuebunny/crossref_metadata_2025 huggingface dataset:
Flux Observation of Induction Machine Based on the Enhanced Sensorless Voltage Model
Authors: Al-Badrani Harith
Published: May 2021

This paper presents the identification of the rotor flux of the induction machine. In the field-oriented control topology, since the terminal stator voltages are a pulsating voltage, so the only way is to calculate the reference values of the voltages from the inverter states phase. At very low speed, the reconstructed voltages are nearly not real, so that, the range of speed rotation of an encoder-less field-oriented control is not quite enough to cover all the speed range. However, the design of a 3-phase inverter which is prepared by silicon carbide (SiC)-MOSFETs with inserting an output filter between the inverter and the machine may supply sinusoidal voltages and currents at the output. The high switching frequency which can be applied with the SiC MOSFETs permits the proposal and implementation of a small low pass LC filter that can be equipped with the inverter output side. With this structure, it is possible to reduce the harmonic of the output voltages in addition to reduce the content of the current harmonics causing in a practically sinusoidal voltage as confirmed in the experimental results of this work. The main goal of this outline is two points, on the first side it can be reduce the winding machine stress, therefore, it is minimizing the harmonic in the voltages at the machine terminals. And on the other hand, is to use the measured voltages as an alternative of the recalculated ones to enhance the voltage model and the performance of the control scheme. It is predictable that the range of machine speed of an encoder-less field-oriented control can be extended.
Structural performance of reinforced self-compacting concrete columns produced with palm oil fuel ash
Authors: Mujedu K A , A-Kadir M A , Ismail M , Mastor M N M A , Zuhan N , Aluko O G , Sif M T M A
Published: May 2021

Palm oil fuel ash (POFA) is an agricultural waste produced from the palm oil industries and disposes off into an open ground without any reprocessing or profitable return, has been established to enrich concrete durability as well as mechanical properties when used to replace cement. However the POFA used to partially substitute cement in self-compacting concrete (SCC) production were done on material properties by fabricating standard specimens such as cylinders, prisms and cubes. Moreover, the utilization of POFA to partially substitute cement to cast reinforced concrete structural members is not common compared to fly ash and ground granulated blast furnace slag. This study therefore focuses on structural performance of reinforced self-compacting concrete columns produced with palm oil fuel ash. Two mixes of SCC containing 0% and 15% of POFA were prepared to fabricate the columns. The main variables considered were percentage of POFA content, percentage of steel reinforcement ratio (2% and 3%) and thickness of concrete cover (25 mm and 35 mm). Eight columns were fabricated altogether and tested under axial compression load up to failure. The results of the test revealed that the ultimate axial capacity of reinforced SCC columns produced with POFA is higher than the columns produced without POFA by approximately 2.6% and 2.2% for 25 mm and 35 mm concrete covers, and 2.9% and 2.5% for 2% and 3% steel reinforcement ratios. It is also observed that the load-deflection pattern of reinforced SCC columns produced with and without POFA follow similar trends. However, columns produced with POFA showed slightly lower stiffness than the columns produced without POFA.
Effect of reduction of heat using Kenaf fibrous pulverised fuel ash concrete in hydration process
Authors: Azzmi N M , Yatim J M , Mazlan D , Md Ulang Norhidayah , Hashim S Z , Kamarudin N A S
Published: May 2021

Since early civilization, the toughness of concrete Pozzolanic materials, either naturally occurring or artificially produced, has long been in practice. The purpose of pozzolanic materials in the cement industry especially contributes to strengthening the concrete structure after its reaction with water. However, the increase in temperature of the cement mixture after the addition of water becomes a great concern. Which can affect the quality of the structure afterward. Therefore, this research mainly focuses on the study of the heat of hydration process in the early stages of a concrete mixture. Four types of concrete mixtures are used in this study are Ordinary Portland Cement concrete (OPC), pulverised fuel ash cement concrete (PFAC), Kenaf fibrous concrete (KFC), and Kenaf pulverised fuel ash concrete (KFPC). The temperature of all samples was recorded for 72 hours. The selection of pozzolanic material of PFA cement in the mixture was found to play an important role in controlling the heat. The result indicated that the replacement of 25% of PFA (for PFAC sample) and addition of Kenaf fiber (for KFC sample) in the concrete mixture reduced the heat of hydration by 5% and 3% respectively, compared to the conventional OPC mixture. Thus, the combination of PFA and Kenaf fiber in one concrete mixture can result in a 6% reduction of the heat of hydration. Hence, the partial replacement of cement with pulverised fuel ash and kenaf fiber is beneficial, especially for mass concrete where it can minimize the effect of thermal cracking of the structure due to excessive heat rise.
Tracking Performance of Pneumatic Position Using Fractional-Order PIλDμ Controller
Authors: Naji Muftah Mohamed , Athif Mohd Faudzi Ahmad
Published: May 2021

An Intelligent Pneumatic Actuator (IPA) system is known to be highly nonlinear, subject to nonlinearities which make it difficult to control the precise position of the actuator. Thus, system modelling is crucial in creating a mathematical model that demonstrates the dynamics of a system. In this study, the pneumatic system has been modelled by an autoregressive with exogenous input (ARX) model structure, while PID and fractional orders PIλDμ (FOPID) were used as control strategies. Finally, a simulation-based comparative analysis was evaluated and addressed to decide which controller provides a better tracking performance (Steady State Error (e ss), Percentage of Overshoot (%Os), Settling Time (7¾ and Rise Time (7>)).
Review on current advances and consideration issues in preparing soil-rock mixture for laboratory testing
Authors: Salimun N , Mohamad H
Published: May 2021

An extensive review of the soil-rock mixture strength measurement has been carried under various geomaterials and experimental methods. Primarily, the factors affecting the SRM mechanical behaviour and the testing methods discussed to further understand the importance of the sample preparation process before conducting laboratory testing. The soil-rock mixture is prepared in the laboratory using the test scheme proposed from very recent literature to perceive the dependence of the sample preparation procedure on the result of strength measurement. Then, a thorough literature review conducted to highlight the significant observations that are important in developing a systematic procedure for soil-rock mixture laboratory testing. Furthermore, the findings conclude that besides the soil-rock ratio, the moisture content, type of soil or finer grain component, and variation block strength or coarse grain component are essential factors that need to be determined while preparing soil-rock mixture samples before conducting the laboratory testing. Finally, for the future research direction of preparing a systematic standard for soil-rock mixture samples, several key points include the particle size, the range of soil-rock ratio, the geomaterials used, and the compaction degree proposed to be considered.
Effects of Hot-Press Temperature and Mix Proportions on Mechanical Behaviours of Hybrid Coconut Fibre Particleboard
Authors: Tawasil D N , Aminudin E , Lim H A S , Chung L P , Soh N M Z N
Published: May 2021

This paper represents the process in selecting the suitable hot press temperature, resin content and percentage of proportion for sawdust and coconut fibre in producing particleboard by investigating the mechanical behaviours (BS EN 310: 1993) and physical properties (BS EN 323:1993, BS EN 324). The process begins with preparation of materials which are sawdust and coconut fibre that were sieved and retained at 5mm sieve with oven-dried. The mixing process of this hybrid particle board which consist from sawdust and coconut fibre with the additional of resin (Urea Formaldehyde) being sprayed and hot pressed. The thickness and density for this experiment were fixed with targeted at 16mm and 650 kg/m 3 respectively. The hot press temperature was manipulated varies from 140 °C, 160°C and 180°C, resin content varies from 6%, 8% and 10%, while the percentage of proportion (%) of sawdust (SD) to coconut fibre (CF) varies from 100SD:0CF, 70SD:30CF, 50SD:50CF, 30SD:70CF and 0SD:100CF of weight. The particleboards were conditioned to room temperature for 7 days before tested for physical and mechanical properties. The results show that the suitable hot press temperature is 160°C, resin content at 8% and percentage of proportion for sawdust to coconut fibre are 30SD:70CF and 0SD:100CF for particleboard where the Modulus of Elasticity (MOE) 2689 N/mm² and 2450 N/mm 2 respectively, Modulus of Rupture (MOR) are 18.74 N/mm 2 and 20.69 N/mm 2 respectively in accordance to BS EN 312:2010.
Quantum process tomography of a Mølmer-Sørensen gate via a global beam
Authors: Tinkey Holly N , Meier Adam M , Clark Craig R , Seck Christopher M , Brown Kenton R
Published: May 2021

We present a framework for quantum process tomography of two-ion interactions that leverages modulations of the trapping potential and composite pulses from a global laser beam to achieve individual-ion addressing. Tomographic analysis of identity and delay processes reveals dominant error contributions from laser decoherence and slow qubit frequency drift during the tomography experiment. We use this framework on two co-trapped 40Ca+ ions to analyze both an optimized and an overpowered Mølmer–Sørensen gate and to compare the results of this analysis to a less informative Bell-state tomography measurement and to predictions based on a simplified noise model. These results show that the technique is effective for the characterization of two-ion quantum processes and for the extraction of meaningful information about the errors present in the system. The experimental convenience of this method will allow for more widespread use of process tomography for characterizing entangling gates in trapped-ion systems.
Textured, lead-free piezoelectric ceramics with high figure of merit for energy harvesting
Authors: Haugen Astri Bjørnetun , Ringgaard Erling , Levassort Franck
Published: May 2021

Piezoelectrics are key materials for energy conversion, for example in ultrasound transducers and energy harvesters. This work presents the synthesis and characterization of the lead-free piezoelectric composition (Li0.06(K0.52Na0.48)0.94)(Nb0.71Ta0.29)O3 doped with 0.25 mol% Mn (KNNLTM) as textured ceramics. Templated grain growth from NaNbO3 platelet templates aligned by tape casting was used to introduce texture, and after sintering for 14 h at 1100 °C this produced up to 84% (100)pc grain orientation. After high temperature poling, the textured samples exhibit reasonable piezoelectric response with d
33 values up to 171 pC N−1, and k
t values of 0.35, which is 71% of the response obtained in a single crystal of the same composition. The low relative dielectric permittivity of the textured and high temperature-poled KNNLTM (ϵ
33
T/ϵ
0 down to 182) resulted in record-high piezoelectric voltage constants (g
33 up to 101 mV m N−1), higher than previously reported for lead-free piezoelectric ceramics, as well as very high figure of merit (d
33
g
33 up to 16 × 10−12 m3 J−1) for non-resonant energy harvesting in compression. These numbers make the textured KNNLTM materials of this work highly promising for use in thickness mode, non-resonant piezoelectric energy harvesters.
PEG size effect and its interaction with Fe3O4 nanoparticles synthesized by solvothermal method: morphology and effect of pH on the stability
Authors: Namikuchi Eliane A , Gaspar Rafael D L , da Silva Douglas S , Raimundo Ivo M , Mazali Italo O
Published: May 2021

The synthesis and characterization of Fe3O4 magnetic nanoparticles (MNPs) obtained by the solvothermal method in ethyleneglycol with the addition of polyethyleneglycol (PEG) with molar mass of 4000, 8000 and 20000 g mol−1 are described, aimed at evaluating its effect on the size, morphology and stability of the nanoparticle. The syntheses were carried out by solubilizing the precursors at 85 and 140 °C, providing smaller nanoparticles as well as smaller crystallites at higher temperatures, while the effect of PEG was less evident. Measurements of nanoparticle surface areas synthesized with PEG 4000 and 20000 g mol−1 at 140 °C provided values of 76 and 14 m2 g−1, respectively, indicating that PEG 4000 surrounds the crystallites, while PEG 20000 preferably surrounds the whole MNP. As a consequence, MNP with very dissimilar porosities were obtained. Electron energy loss spectroscopy (EELS) indicated that MNP synthesized with PEG 20000 possesses higher electronic density than those obtained with PEG 4000, in agreement with the surface area results. Infrared spectroscopy and thermogravimetric analysis demonstrated the presence of PEG in the particles, whose amount increased as the particle size decreased. Dynamic Light Scattering (DLS) measurements showed that MNP hydrodynamic radius increases with the PEG size and stability in solution increases from pH 5.0 to 9.0 for smaller NP, while polymer presents slight effect on stability for the larger particles. The results obtained in this work show that properties of MNP can be tuned by the dissolution temperature of the chemical precursors and the PEG molar mass, changing their porosity and stability in solution, that are important variables in processes of adsorption, drug delivery and sensor developing.
Discrete logarithms in quasi-polynomial time in finite fields of fixed characteristic
Authors: Kleinjung Thorsten , Wesolowski Benjamin
Published: May 2021

We prove that the discrete logarithm problem can be solved in quasi-polynomial expected time in the multiplicative group of finite fields of fixed characteristic. More generally, we prove that it can be solved in the field of cardinality

p
n

p^n

in expected time

(
p
n

)

2

log
2

⁡
(
n
)
+
O
(
1
)

(pn)^{2\log _2(n) + O(1)}

.
Refugees: A Very Short Introduction
Authors: Loescher Gil
Published: May 2021

Refugees: A Very Short Introduction explores the causes and impact of today's refugee crises for receiving states and societies, for global order, and for refugees themselves. Refugees and other forced migrants are one of the great challenges in the world today. All over the globe people leave their home countries to escape war, natural disasters, and cultural and political oppression. Unfortunately, despite many years of experience, the international community struggles to provide an adequate response to this vast population in need. This VSI discusses the need to understand the realities of the contemporary refugee situation in order to best respond to current and future challenges.
Responding to refugee movements
Authors: Loescher Gil
Published: May 2021

This chapter discusses the global refugee system. The fundamental principles are detailed in the 1951 Refugee Convention and the core institution of the system is the Office of the United Nations High Commissioner for Refugees (UNHCR). These instruments are supposed to ensure that refugees have access to key rights. However, today’s global refugee system has often had difficulty in providing effective responses to refugee movements. The chapter examines the principal constraints on responding to refugee movements through international cooperation within the context of a radically changing international political system, an expanding global mobility regime, and a growing and diverse group of displaced people in need of assistance and protection.
3. The what of creativity
Authors: Glăveanu Vlad
Published: May 2021

This chapter examines the ‘what’ of creativity, which is represented by those products coming out of creative processes. These products vary widely. Designer chairs, cups made of entirely new and sustainable materials, and the latest version of a mobile phone are all tangible outcomes. But ideas can also be called creative even if they are, at least at first, intangible. To complicate things further, processes can also be considered creative outcomes. The chapter then expands the focus to creative artefacts. It distinguishes between ‘little’ and ‘Big’ forms of creativity. The chapter also reflects on both the positive and negative sides of creativity.
Human Physiology: A Very Short Introduction
Authors: Davies Jamie A.
Published: May 2021

Human Physiology: A Very Short Introduction explores how the human body works, senses, reacts, and defends itself. Physiology is the science of life. It considers how human bodies are supplied with energy, how they maintain their internal parameters, the ways in which they gather and process information or take action, and the creation of new generations. This VSI examines the experiments undertaken to understand the interplay of the vast variety of physiological mechanisms and principles within us, and analyses the ethical issues involved. It also looks at how enhanced understandings of physiological knowledge can help inform medical research and care.
Optimizing preoperative antibiotics in patients with β-lactam allergies: A role for pharmacy
Authors: Kwiatkowski Shaina , Mulugeta Surafel , Davis Susan , Kenney Rachel , Kalus James , Walton Leslie , Patel Nisha
Published: May 2021

Purpose

Patients with a reported β-lactam allergy (BLA) are often given alternative perioperative antibiotic prophylaxis, increasing risk of surgical site infections (SSIs), acute kidney injury (AKI), and Clostridioides difficile infection (CDI). The purpose of this study was to implement and evaluate a pharmacist-led BLA clarification interview service in the preoperative setting.

Methods

A pharmacist performed BLA clarification telephone interviews before elective procedures from November 2018 to March 2019. On the basis of allergy history and a decision algorithm, first-line preoperative antibiotics, alternative antibiotics, or allergy testing referral was recommended. The pharmacist intervention (PI) group was compared to a standard of care (SOC) group who underwent surgery from November 2017 to March 2018.

Results

Eighty-seven patients were included, with 50 (57%) and 37 (43%) in the SOC and PI groups, respectively. The most common surgeries included orthopedic surgery in 41 patients (47%) and neurosurgery in 17 patients (20%). In the PI group, all BLA labels were updated after interview. Twenty-three patients were referred for allergy testing, 12 of the 23 (52%) completed BLA testing, and penicillin allergies were removed for 9 of the 12 patients. Overall, 28 of the 37 (76%) pharmacy antibiotic recommendations were accepted. Cefazolin use significantly increased from 28% to 65% after the intervention (P = 0.001). SSI occurred in 5 (10%) patients in the SOC group and no patients in the PI group (P = 0.051). All of these SSIs were associated with alternative antibiotics. Incidence of AKI and CDI was similar between the groups. No allergic reactions occurred in either group.

Conclusion

Implementation of a pharmacy-driven BLA reconciliation significantly increased β-lactam preoperative use without negative safety outcomes.
Cosmic meteorology
Authors: Lockwood Mike , Owens Mat
Published: May 2021

Mike Lockwood and Mat Owens discuss how eclipse observations are aiding the development of a climatology of near-Earth space
Identification of evolutionarily stable functional and immunogenic sites across the SARS-CoV-2 proteome and greater coronavirus family
Authors: Wang Chen , Konecki Daniel M , Marciano David C , Govindarajan Harikumar , Williams Amanda M , Wastuwidyaningtyas Brigitta , Bourquard Thomas , Katsonis Panagiotis , Lichtarge Olivier
Published: May 2021

Motivation

Since the first recognized case of COVID-19, more than 100 million people have been infected worldwide. Global efforts in drug and vaccine development to fight the disease have yielded vaccines and drug candidates to cure COVID-19. However, the spread of SARS-CoV-2 variants threatens the continued efficacy of these treatments. In order to address this, we interrogate the evolutionary history of the entire SARS-CoV-2 proteome to identify evolutionarily conserved functional sites that can inform the search for treatments with broader coverage across the coronavirus family.

Results

Combining coronavirus family sequence information with the mutations observed in the current COVID-19 outbreak, we systematically and comprehensively define evolutionarily stable sites that may provide useful drug and vaccine targets and which are less likely to be compromised by the emergence of new virus strains. Several experimentally validated effective drugs interact with these proposed target sites. In addition, the same evolutionary information can prioritize cross reactive antigens that are useful in directing multi-epitope vaccine strategies to illicit broadly neutralizing immune responses to the betacoronavirus family. Although the results are focused on SARS-CoV-2, these approaches stem from evolutionary principles that are agnostic to the organism or infective agent.

Availability and implementation

The results of this work are made interactively available at http://cov.lichtargelab.org.

Supplementary information

Supplementary data are available at Bioinformatics online.
Localization of kisspeptin, NKB, and NK3R in the hypothalamus of gilts treated with the progestin altrenogest
Authors: Lindo Ashley N , Thorson Jennifer F , Bedenbaugh Michelle N , McCosh Richard B , Lopez Justin A , Young Samantha A , Meadows Lanny J , Bowdridge Elizabeth C , Fergani Chrysanthi , Freking Bradley A , Lehman Michael N , Hileman Stanley M , Lents Clay A
Published: May 2021

Mechanisms in the brain controlling secretion of gonadotropin hormones in pigs, particularly luteinizing hormone (LH), are poorly understood. Kisspeptin is a potent LH stimulant that is essential for fertility in many species, including pigs. Neurokinin B (NKB) acting through neurokinin 3 receptor (NK3R) is involved in kisspeptin-stimulated LH release, but organization of NKB and NK3R within the porcine hypothalamus is unknown. Hypothalamic tissue from ovariectomized (OVX) gilts was used to determine the distribution of immunoreactive kisspeptin, NKB, and NK3R cells in the arcuate nucleus (ARC). Almost all kisspeptin neurons coexpressed NKB in the porcine ARC. Immunostaining for NK3R was distributed throughout the preoptic area (POA) and in several hypothalamic areas including the periventricular and retrochiasmatic areas but was not detected within the ARC. There was no colocalization of NK3R with gonadotropin-releasing hormone (GnRH), but NK3R-positive fibers in the POA were in close apposition to GnRH neurons. Treating OVX gilts with the progestin altrenogest decreased LH pulse frequency and reduced mean circulating concentrations of LH compared with OVX control gilts (P < 0.01), but the number of kisspeptin and NKB cells in the ARC did not differ between treatments. The neuroanatomical arrangement of kisspeptin, NKB, and NK3R within the porcine hypothalamus confirms they are positioned to stimulate GnRH and LH secretion in gilts, though differences with other species exist. Altrenogest suppression of LH secretion in the OVX gilt does not appear to involve decreased peptide expression of kisspeptin or NKB.
Design Criteria for Process-Based Restoration of Fluvial Systems
Authors: Ciotti Damion C , Mckee Jared , Pope Karen L , Kondolf G Mathias , Pollock Michael M
Published: May 2021

Process-based restoration of fluvial systems removes human constraints on nature to promote ecological recovery. By freeing natural processes, a resilient ecosystem may be restored with minimal corrective intervention. However, there is a lack of meaningful design criteria to allow designers to evaluate whether a project is likely to achieve process-based restoration objectives. We describe four design criteria to evaluate a project's potential: the expansion of fluvial process space and connectivity lost because of human alterations, the use of intrinsic natural energy to do the work of restoration, the use of native materials that do not overstabilize project elements, and the explicit incorporation of time and adaptive management into project design to place sites on recovery trajectories as opposed to attempts to “restore” sites via a single intervention. Applications include stream and infrastructure design and low-carbon construction. An example is presented in California's Sierra Nevada foothills.
Prediction of response to repetitive transcranial magnetic stimulation in phantom sounds based on individual brain anatomy
Authors: Poeppl Timm B , Schecklmann Martin , Sakreida Katrin , Landgrebe Michael , Langguth Berthold , Eickhoff Simon B
Published: May 2021

Non-invasive brain stimulation can reduce the severity of tinnitus phantom sounds beyond the time of stimulation by inducing regional neuroplastic changes. However, there are no good clinical predictors for treatment outcome. We used machine learning to investigate whether brain anatomy can predict therapeutic outcome. Sixty-one chronic tinnitus patients received repetitive transcranial magnetic stimulation of left dorsolateral prefrontal and temporal cortex. Before repetitive transcranial magnetic stimulation, a structural magnetic resonance image was obtained from all patients. To predict individual treatment response in new subjects, we employed a support vector machine ensemble for individual out-of-sample prediction. In the cross-validation, the support vector machine ensemble based on stratified sub-sampling and feature selection yielded an area under the curve of 0.87 for prediction of therapy success in new, previously unseen subjects. This corresponded to a balanced accuracy of 83.5%, sensitivity of 77.2% and specificity of 87.2%. Investigating the most selected features showed the involvement of the auditory cortex but also revealed a network of non-auditory brain areas. These findings suggest that idiosyncratic brain patterns accurately predict individual responses to repetitive transcranial magnetic stimulation treatment for tinnitus. Our findings may hence pave the way for future investigations into the precision treatment of tinnitus, involving automatic identification of the appropriate treatment method for the individual patient.
Techno-economic analysis of the Li-ion batteries and reversible fuel cells as energy-storage systems used in green and energy-efficient buildings
Authors: Mayyas Ahmad , Chadly Assia A , Khaleel Iman , Maalouf Maher
Published: May 2021

Green buildings have become broadly adopted in commercial and residential sectors with the objective of minimizing environmental impacts through reductions in energy usage and water usage and, to a lesser extent, minimizing environmental disturbances from the building site. In this paper, we develop and discuss a techno-economic model for a green commercial building that is 100% powered by a photovoltaic (PV) system in stand-alone configuration. A medium-sized office building in El Paso, TX was modelled to rely on a photovoltaic system to supply all of its electricity needs either directly from the PV system or through an energy-storage system (ESS) using Li-ion batteries (LIBs) or reversible fuel cells (RFCs). Cost results show that a 400-kW PV system can generate electricity at a cost of 2.21 cents/kWh in El Paso, TX and the average levelized cost of energy storage (LCOS) using 450-kW RFC is ~31.3 cents/kWh, while this could reach as low as 25.5 cents/kWh using a small LIB ESS. While the RFC provides the flexibility required to meet building-energy demand, LIBs may not be able to meet building needs unless the storage size is increased substantially, which in turn incurs more energy-storage cost, making LIBs less favourable from an economic perspective. Sensitivity analysis revealed that capital cost, discount rate and expected system lifetime play key roles in shaping the LCOS in both systems.
Female preferences for male golden snub-nosed monkeys vary with male age and social context
Authors: Yang Xi , Berman Carol M , Hu Hanyu , Hou Rong , Huang Kang , Wang Xiaowei , Zhao Haitao , Wang Chengliang , Li Baoguo , Zhang Pei
Published: May 2021

Age is a key factor affecting sexual selection, as many physical and social traits are age-related. Although studies of primate mate choice often consider particular age-related traits, few consider the collective effects of male age. We tested the hypothesis that female golden snub-nosed monkeys Rhinopithecus roxellana prefer prime aged males (10–15 years) over younger and older males. We examined a habituated, provisioned troop during a 3-year study in the Qinling Mountains, China. Prime age males were more likely to be resident males of 1-male units (OMUs) than males of other ages. Since females are free to transfer between OMUs, the number of females per OMU can be indicative of female preferences. We examined the number of females per OMU, and found that it increased with resident male age up to 7–8 years, and declined after 12 years, such that prime age resident males had more females than other resident males. Females also initiated extra-unit copulations with high-ranking prime age males at significantly higher rates than with other males. Nevertheless, females tended to transfer from OMUs with high-ranking, older resident males to those with low-ranking, younger resident males. Thus, females appear to use different strategies when choosing social mates and extra-unit mates (i.e., different social contexts). We speculate that females may perceive early signs of aging in males and trade off the benefits and costs of high rank versus male senescence. This study lays the groundwork for future studies that examine possible direct and indirect benefits of such strategies.
Initiation of and persistence with P2Y12 inhibitors in patients with myocardial infarction according to revascularization strategy: a nationwide study
Authors: Tajchman Daniel H , Nabi Hafsah , Aslam Mohsin , Butt Jawad H , Grove Erik L , Engstrøm Thomas , Holmvang Lene , Fosbøl Emil L , Køber Lars , Sørensen Rikke
Published: May 2021

Background

We aimed to analyse initiation of and persistence with P2Y12 inhibitors after first-time myocardial infarction (MI).

Methods and results

Using Danish nationwide registries, we identified patients ≥30 years with first-time MI during 1 January 2005–30 June 2016 and subsequent prescriptions of P2Y12 inhibitors. Independent factors related to initiation of and persistence with P2Y12 inhibitors were analysed by multivariable logistic regression and a Cox proportional hazards model. Patients were stratified by revascularization strategy: percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), or medical therapy alone (MTA). Overall, 79 597 MI patients were included with 39 172 undergoing PCI, 2619 CABG, and 16 640 MTA, showing initiation of P2Y12 inhibitors of 93.4%, 49.0%, and 51.5%, respectively. Congestive heart failure, cerebrovascular disease, cardiac dysrhythmias, renal failure, previous bleeding, and oral anticoagulants were associated with less initiation of P2Y12 inhibitors. Female sex was associated with less initiation of P2Y12 inhibitors following MTA. MTA, coronary angiography, cerebrovascular disease, diabetes with complications, previous bleeding, antidiabetics, and ticagrelor as P2Y12 inhibitor were associated with non-persistence, whereas female sex, advanced age, and concomitant pharmacotherapy with angiotensin-converting enzyme inhibitors, beta-blockers, statins, oral anticoagulants, and aspirin were associated with high persistence.

Conclusion

Initiation of P2Y12 inhibitors in PCI-treated MI patients was high in contrast to those treated with CABG or MTA and patients with certain comorbidities. Further studies on the benefit–risk ratio of P2Y12 inhibitors in CABG-treated or MTA-treated patients and patients with comorbidities after first-time MI are warranted, as is focus on persistence among patients receiving MTA, patients with comorbidities, and users of ticagrelor.
The Indigenous South American Tsimane Exhibit Relatively Modest Decrease in Brain Volume With Age Despite High Systemic Inflammation
Authors: Irimia Andrei , Chaudhari Nikhil N , Robles David J , Rostowsky Kenneth A , Maher Alexander S , Chowdhury Nahian F , Calvillo Maria , Ngo Van , Gatz Margaret , Mack Wendy J , Law E Meng , Sutherland M Linda , Sutherland James D , Rowan Christopher J , Wann L Samuel , Allam Adel H , Thompson Randall C , Michalik David E , Cummings Daniel K , Seabright Edmond , Alami Sarah , Garcia Angela R , Hooper Paul L , Stieglitz Jonathan , Trumble Benjamin C , Gurven Michael D , Thomas Gregory S , Finch Caleb E , Kaplan Hillard
Published: May 2021

Brain atrophy is correlated with risk of cognitive impairment, functional decline, and dementia. Despite a high infectious disease burden, Tsimane forager-horticulturists of Bolivia have the lowest prevalence of coronary atherosclerosis of any studied population and present few cardiovascular disease (CVD) risk factors despite a high burden of infections and therefore inflammation. This study (a) examines the statistical association between brain volume (BV) and age for Tsimane and (b) compares this association to that of 3 industrialized populations in the United States and Europe. This cohort-based panel study enrolled 746 participants aged 40–94 (396 males), from whom computed tomography (CT) head scans were acquired. BV and intracranial volume (ICV) were calculated from automatic head CT segmentations. The linear regression coefficient estimate β^T of the Tsimane (T), describing the relationship between age (predictor) and BV (response, as a percentage of ICV), was calculated for the pooled sample (including both sexes) and for each sex. β^T was compared to the corresponding regression coefficient estimate β^R of samples from the industrialized reference (R) countries. For all comparisons, the null hypothesis β T = β R was rejected both for the combined samples of males and females, as well as separately for each sex. Our results indicate that the Tsimane exhibit a significantly slower decrease in BV with age than populations in the United States and Europe. Such reduced rates of BV decrease, together with a subsistence lifestyle and low CVD risk, may protect brain health despite considerable chronic inflammation related to infectious burden.
Increasing Prevalence and Stable Incidence Rates of Inflammatory Bowel Disease Among First Nations: Population-Based Evidence From a Western Canadian Province
Authors: Peña-Sánchez Juan Nicolás , Osei Jessica Amankwah , Marques Santos Jose Diego , Jennings Derek , Andkhoie Mustafa , Brass Colten , Bukassa-Kazadi Germain , Lu Xinya , Johnson-Jennings Michelle , Porter Linda , Porter Rob , Quintin Carol-Lynne , Sanderson Rhonda , Teucher Ulrich , Fowler Sharyle
Published: May 2021

Background

There is limited to no evidence of the prevalence and incidence rates of inflammatory bowel disease (IBD) among Indigenous peoples. In partnership with Indigenous patients and family advocates, we aimed to estimate the prevalence, incidence, and trends over time of IBD among First Nations (FNs) since 1999 in the Western Canadian province of Saskatchewan.

Methods

We conducted a retrospective population-based study linking provincial administrative health data from the 1999-2000 to 2016-2017 fiscal years. An IBD case definition requiring multiple health care contacts was used. The prevalence and incidence data were modeled using generalized linear models and a negative binomial distribution. Models considered the effect of age groups, sex, diagnosis type (ulcerative colitis [UC], Crohn disease [CD]), and fiscal years to estimate prevalence and incidence rates and trends over time.

Results

The prevalence of IBD among FNs increased from 64/100,000 (95% confidence interval [CI], 62-66) in 1999-2000 to 142/100,000 (95% CI, 140-144) people in 2016-2017, with an annual average increase of 4.2% (95% CI, 3.2%-5.2%). Similarly, the prevalence of UC and CD, respectively, increased by 3.4% (95% CI, 2.3%-4.6%) and 4.1% (95% CI, 3.3%-4.9%) per year. In contrast, the incidence rates of IBD, UC, and CD among FNs depicted stable trends over time; no statistically significant changes were observed in the annual change trend tests. The ratio of UC to CD was 1.71.

Conclusions

We provided population-based evidence of the increasing prevalence and stable incidence rates of IBD among FNs. Further studies are needed in other regions to continue understanding the patterns of IBD among Indigenous peoples.
Coronavirus and sports leagues: obtaining a fair ranking when the season cannot resume
Authors: Csató László
Published: May 2021

Many sports leagues are played in a tightly scheduled round-robin format, leaving a limited time window to postpone matches. If the season cannot resume due to an external shock such as the coronavirus pandemic in 2020, the ranking of the teams becomes non-trivial: it is necessary to account for schedule imbalances and possibly for the different number of matches played. First in the literature, we identify a set of desired axioms for ranking in these incomplete tournaments. It is verified that the generalized row sum, a parametric family of scoring rules, satisfies all of them. In particular, the well-established least-squares method maximizes the influence of the strength of opponents on the ranking. Our approach is applied for six major premier European soccer competitions, where the rankings are found to be robust concerning the weight of adjustment for the strength of the opponents. Some methodologically simpler alternative policies are also discussed.
Corbiculate Bees (Hymenoptera: Apidae): Exploring the Limits of Morphological Data to Solve a Hard Phylogenetic Problem
Authors: Porto Diego Sasso , Almeida Eduardo A B
Published: May 2021

Corbiculate bees comprise a distinctive radiation of animals including many familiar species, such as honey bees and bumble bees. The group exhibits a broad variety of morphologies and behaviors, including solitary, social, and cleptoparasitic lifestyles. Since corbiculate bees play a critical role for the interpretation of eusocial behaviors, understanding their phylogeny is crucial to explain patterns and mechanisms of social evolution. Despite advances to unveil corbiculate relationships employing genomic data, the drivers of conflict between molecular and morphological hypotheses are still not fully understood. Morphological datasets favor a single origin for highly eusocial behaviors (i.e., Apini + Meliponini) whereas molecular datasets favor other scenarios (e.g., Bombini + Meliponini). Explanations for this incongruence have been suggested, including quality, quantity, and source of data or methodological issues. In this work we tackled this problem by generating the most extensive morphological dataset for the corbiculate bee species by exploring characters from all body regions, including external and internal adult skeletal anatomy. We produced a matrix with 289 characters for 53 taxa of Apidae, including 24 corbiculate bees. We explored different analyses and optimality criteria including extended implied weights parsimony and two partitioning schemes for Bayesian inferences. We contrasted hypotheses with Bayesian topological tests and conducted analyses to investigate if characters were prone to concerted convergence. Our results are congruent with the conclusions of previous studies based on morphology, recovering Apini sister to Meliponini and both of them together sister to Bombini. Finally, we provide our interpretations on the corbiculate controversy and provide a conciliatory scenario about this issue.
Integrated Taxonomic Revision of AfrotropicalXyleborinus(Curculionidae: Scolytinae) Reveals High Diversity After Recent Colonization of Madagascar
Authors: Eliassen Jonas M , Jordal Bjarte H
Published: May 2021

The ambrosia beetle genus Xyleborinus Reitter, 1913 is particularly species rich in Madagascar where the genus exhibits extraordinary morphological variation not seen elsewhere. This study provides the first detailed molecular phylogeny of the genus based on COI, 28S, and CAD gene fragments. Biogeographical and taxonomic hypotheses were tested for the Afrotropical fauna with a particular focus on the Malagasy radiation. Analyses revealed a single colonization of Madagascar no earlier than 8.5–11.0 Ma, indicating an extraordinary recent radiation on the island which has given rise to at least 32 species. Two recolonization events of the African mainland were strongly supported by the molecular data, with several other intraspecific dispersals to the mainland inferred from species distributions. A taxonomic re-evaluation of all Afrotropical Xyleborinus resulted in several taxonomic changes. We found that morphological differences associated with COI divergence higher than 7% indicated different species. Twelve new species are described: Xyleborinus castriformis Eliassen & Jordal, sp. nov., Xyleborinus clivus Eliassen & Jordal, sp. nov., Xyleborinus concavus Eliassen & Jordal, sp. nov., Xyleborinus coronatus Eliassen & Jordal, sp. nov., Xyleborinus diadematus Eliassen & Jordal, sp. nov., Xyleborinus laevipennis Eliassen & Jordal, sp. nov., Xyleborinus magnispinosus Eliassen & Jordal, sp. nov., Xyleborinus margo Eliassen & Jordal, sp. nov., Xyleborinus ntsoui Eliassen & Jordal, sp. nov., Xyleborinus singularis Eliassen & Jordal, sp. nov., Xyleborinus tuberculatus Eliassen & Jordal, sp. nov., and Xyleborinus turritus Eliassen & Jordal, sp. nov., all from Madagascar. New synonyms are proposed for Xyleborinus aemulus (Wollaston, 1869) [=Xyleborinus spinifer (Eggers, 1920)], Xyleborinus andrewesi (Blandford, 1896) [=Xyleborinus mimosae (Schedl, 1957)], Xyleborinus dentellus (Schedl, 1953) [=Xyleborinus forcipatus (Schedl, 1957)], Xyleborinus octospinosus (Eggers, 1920) [=Xyleborinus mitosomipennis (Schedl, 1953)], and Xyleborinus similans (Eggers, 1940) [=Xyleborinus sclerocaryae (Schedl, 1962)]. Two species were given new status: Xyleborinus profundus (Schedl, 1961) is elevated from subspecies of Xyleborinus aduncus (Schedl, 1961), and Xyleborinus mitosomus (Schedl, 1965) is reinstated from its previous synonymy with Xyleborinus spinosus (Schaufuss, 1891). Xyleborus gracilipennis Schedl 1957 is reverted to its original genus, and a similar status is confirmed for Xyleborus collarti Eggers 1932. The number of taxonomically valid Xyleborinus species in the Afrotropical region is now 47, which includes 3 adventive species. Revised diagnoses for all species and a key for species identification are provided.
Chemical Profiling and Characterization of Anthraquinones from Two Bulbine Species and Dietary Supplements Using Liquid Chromatography–High Resolution Mass Spectrometry
Authors: Avula Bharathi , Bae Ji-Yeong , Wang Yan-Hong , Wang Mei , Ali Zulfiqar , Khan Ikhlas A
Published: May 2021

Background

Bulbine natalensis Baker and Bulbine frutescens (L.) Willd., belonging to the family Asphodelaceae, are widely distributed in South Africa and traditionally used as an aphrodisiac and skin remedies.

Objective

The aim of this study is to develop an analytical method for chemical profiling and identification of components in Bulbine species, which would be useful for herbal identification and understanding of the biological activity of B. natalensis in terms of safety and benefits to human health.

Method

The anthraquinone-type compounds were structurally characterized from the extracts of dried stem and roots of Bulbine species and dietary supplements using liquid chromatography–quadrupole time-of-flight mass spectrometry (LC-QToF) with negative and positive ion electrospray. The calculated accurate masses of the protonated and deprotonated molecules and fragment ions were used for identification of the components from two Bulbine species.

Results

A total of 55 anthraquinone-type compounds, including 11 standard compounds, were identified in the crude extracts of two Bulbine species. Two Bulbine species and dietary supplements were clustered into different groups and possible chemical markers were identified.

Conclusions

The developed analytical method provided a fast and economic method for quality assessment of Bulbine species in dietary supplements based on anthraquinone-type compounds.

Highlights

This study reports holistic chemical profiling of Bulbine species using LC-QToF. The developed analytical method enabled non-targeted analysis of components in B. natalensis and B. frutescens, and is recommended for commercial and regulatory purposes.
Timing and temperature thresholds of heat stress effects on fertility performance of different parity sows in Spanish herds
Authors: Iida Ryosuke , Piñeiro Carlos , Koketsu Yuzo
Published: May 2021

High temperature is an environmental factor that impairs sow fertility. In this study, we identified the critical weeks for heat stress effects on aspects of fertility performance, namely weaning-to-first-service interval (WSI) and farrowing rate (FR). We also examined the threshold temperatures above which the fertility performance deteriorated and whether there were any differences between parities regarding heat stress effects or thresholds. Performance data of sows in 142 herds from 2011 to 2016 were matched to appropriate weekly averaged daily maximum temperatures (Tmax) from weather stations close to the herds. Two types of ratios (i.e., ratio for WSI and odds ratio for FR) were used to identify the critical weeks for heat stress by comparing the respective measures for two sow groups based on Tmax in different weeks around weaning or service events. The ratios for WSI were calculated between groups of sows exposed to Tmax ≥ 27 °C or <27 °C in each week before weaning, with the Tmax cutoff value based on a recent review study. Similarly, the odds ratios for FR for the two groups were calculated in weeks around service. The weeks with the largest differences in the fertility measures between the two Tmax groups (i.e., the highest ratio for WSI and the lowest odds ratio for FR) were considered to be the critical weeks for heat stress. Also, piecewise models with different breakpoints were constructed to identify the threshold Tmax in the critical week. The breakpoint in the best-fit model was considered to be the threshold Tmax. The highest ratios for WSI were obtained at 1 to 3 wk before weaning in parity 1 and 2 or higher sow groups. The threshold Tmax leading to prolonged WSI was 17 °C for parity 1 sows and 25 °C for parity 2 or higher sows. Increasing Tmax by 10 °C above these thresholds increased WSI by 0.65, and 0.33 to 0.35 d, respectively (P < 0.01). For FR, the lowest odds ratios were obtained at 2 to 3 wk before service in parity 0, 1, and 2 or higher sow groups. The threshold Tmax leading to reductions in FR was 20, 21, and 24 to 25 °C for parity 0, 1, and 2 or higher sow groups, respectively. Increasing Tmax by 10 °C above these thresholds decreased FR by 3.0%, 4.3%, and 1.9% to 2.8%, respectively (P < 0.01). These results indicate that the critical weeks for heat stress were 2 to 3 wk before service for FR and 1 to 3 wk before weaning for WSI. The decreases in fertility performance in parity 0 to 1 sows started at temperatures 3 to 8 °C lower than in parity 2 or higher sows.