bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective Laser Melting Process of Al–Based Pyramidal Horns for the W-Band: Fabrication and Testing
Authors: Lamagna L. , Paiella A. , Masi S. , Bottini L. , Boschetto A. , Veniali F.
Published: January 2021

In the context of exploring the possibility of using Al-powder Selective Laser Melting to fabricate horn antennas for astronomical applications at millimeter wavelengths, we describe the design, the fabrication, the mechanical characterization, and the electromagnetic performance of additive manufactured horn antennas for the W-band. Our aim, in particular, is to evaluate the performance impact of two basic kinds of surface post-processing (manual grinding and sand-blasting) to deal with the well-known issue of high surface roughness in 3D printed devices. We performed comparative tests of co-polar and cross-polar angular response across the whole W-band, assuming a commercially available rectangular horn antenna as a reference. Based on gain and directivity measurements of the manufactured samples, we find decibel-level detectable deviations from the behavior of the reference horn antenna, and marginal evidence of performance degradation at the top edge of the W-band. We conclude that both kinds of post-processing allow achieving good performance for the W-band, but the higher reliability and uniformity of the sand-blasting post-process encourage exploring similar techniques for further development of aluminum devices at these frequencies.
Dimensions of Autistic Traits Rated by Parents of Children and Adolescents with Suspected Autism Spectrum Disorders
Authors: Del Giudice Teresa , Dose Christina , Görtz-Dorten Anja , Steiner Jennifer , Bruning Nicole , Bell Hannah , Roland Pamela , Walter Daniel , Junghänel Michaela , Döpfner Manfred
Published: January 2021

To examine the factor structure of autism spectrum disorder (ASD) and the psychometric properties of the German Symptom Checklist for Autism Spectrum Disorders (SCL-ASD). Data were collected from 312 clinical referrals with suspected ASD (2–18 years). Confirmatory factor analyses and analyses of reliability, convergent and divergent validity were performed. A bifactor model with one general ASD factor and two specific factors (interaction-communication; restricted, repetitive behaviors) provided an adequate data fit. Internal consistencies of the SCL-ASD subscales and the total scale were > .70. Correlations with measures of ASD traits were higher than correlations with measures of externalizing and internalizing symptoms. The results support a factor structure consistent with DSM-5/ICD-11 criteria. The SCL-ASD has sound psychometric properties.
Noise induced quiescence of epileptic spike generation in patients with epilepsy
Authors: Cooray Charith N. , Carvalho Ana , Cooray Gerald K.
Published: January 2021

Clinical scalp electroencephalographic recordings from patients with epilepsy are distinguished by the presence of epileptic discharges i.e. spikes or sharp waves. These often occur randomly on a background of fluctuating potentials. The spike rate varies between different brain states (sleep and awake) and patients. Epileptogenic tissue and regions near these often show increased spike rates in comparison to other cortical regions. Several studies have shown a relation between spike rate and background activity although the underlying reason for this is still poorly understood. Both these processes, spike occurrence and background activity show evidence of being at least partly stochastic processes. In this study we show that epileptic discharges seen on scalp electroencephalographic recordings and background activity are driven at least partly by a common biological noise. Furthermore, our results indicate noise induced quiescence of spike generation which, in analogy with computational models of spiking, indicate spikes to be generated by transitions between semi-stable states of the brain, similar to the generation of epileptic seizure activity. The deepened physiological understanding of spike generation in epilepsy that this study provides could be useful in the electrophysiological assessment of different therapies for epilepsy including the effect of different drugs or electrical stimulation.
Substrate mapping of the left atrium in persistent atrial fibrillation: spatial correlation of localized complex conduction patterns in global charge-density maps to low-voltage areas in 3D contact bipolar voltage maps
Authors: Chierchia Gian-Battista , Sieira Juan , Vanderper Annelies , Osorio Thiago Guimarães , Bala Gezim , Stroker Erwin , Brugada Pedro , Al Houssari Maysam , Cecchini Federico , Mojica Joerelle , Overeinder Ingrid , Bisignani Antonio , Mitraglia Vincenzo , Boveda Serge , Paparella Gaetano , de Asmundis Carlo
Published: January 2021

Purpose

This study aimed to investigate the spatial relationship between low-voltage areas (LVAs) in bipolar voltage mapping (BVM) and localized complex conduction (LCC)-cores in a global, non-contact, charge-density-based imaging, and mapping system (AcM).

Methods

Patients with history of index PVI for PsAF and scheduled for a repeat ablation procedure for recurrence of the same arrhythmia were enrolled between August 2018 and February 2020. All patients underwent both substrate mappings of the left atrium (LA) with the CARTO 3D map-ping system and with AcM.

Results

Ten patients where included in our analysis. All presented with persistency of PVI in all veins at the moment of repeat procedure. There was no linear relationship in BVM maps between SR and CSd (correlation coefficient 0.31 ± 0.15), SR and CSp (0.36 ± 0.12) and CSd and CSp (0.43 ± 0.10). The % overlap of localized irregular activation (LIA), localized rotational activation (LRA) and Focal (F) regions with LVA was lower at 0.2 mV compared to 0.5 mV (4.97 ± 7.39%, 3.27 ± 5.25%, 1.09 ± 1.92% and 12.59 ± 11.81%, 7.8 ± 9.20%, 4.62 ± 5.27%). Sensitivity and specificity are not significantly different when comparing composite maps with different LVA cut-offs. AURC was 0.46, 0.48, and 0.39 for LIA, LRA, and Focal, respectively.

Conclusion

Due to wave front direction dependency, LVAs mapped with BVM in sinus rhythm and during coronary sinus pacing only partially overlap in patients with PsAF. LCC-cores mapped during PsAF partially co-localize with LVAs.
Multi-robot multi-operator collaborative assembly systems: a performance evaluation model
Authors: Boschetti Giovanni , Bottin Matteo , Faccio Maurizio , Minto Riccardo
Published: January 2021

In the last decade, collaborative assembly systems (CAS) are becoming increasingly common due to their ability to merge the flexibility of a manual assembly system with the performance of traditional robotics. Technical constraints, e.g., dedicated tools or resources, or performance requirements, e.g., throughput, could encourage the use of a CAS built around a multi-robot and multi-operator layout, i.e., with a number of resources greater than 2. Starting from the development of a prototype multi-robot multi-operator collaborative workcell, a simulation environment was developed to evaluate the makespan and the degree of collaboration in multi-robot multi-operator CAS. From the simulation environment, a mathematical model was conceptualized. The presented model allows estimating, with a certain degree of accuracy, the performances of the system. The results have investigated how several process characteristics, i.e. the number and type of resources, the resources layout, the task allocation method, and the number of feeding devices, influence the degree of collaboration between the resources. Lastly, the authors propose a compact analytic formulation, based on an exponential function, and define the methods and the influence factors to determine its parameters.
Thermal Ionization for Short-Range Potentials
Authors: Hasler David , Siebert Oliver
Published: January 2021

We study a concrete model of a confined particle in form of a Schrödinger operator with a compactly supported smooth potential coupled to a bosonic field at positive temperature. We show, that the model exhibits thermal ionization for any positive temperature, provided the coupling is sufficiently small. Mathematically, one has to rule out that zero is an eigenvalue of the self-adjoint generator of time evolution—the Liouvillian. This will be done by using positive commutator methods with dilations in the space of scattering functions. Our proof relies on a spatial cutoff in the coupling but does otherwise not require any unnatural restrictions.
Why visiting one’s ageing mother is not enough: on filial duties to prevent and alleviate parental loneliness
Authors: de Vries Bouke
Published: January 2021

As people grow old, many risk becoming chronically lonely which is associated with e.g. depression, dementia, and increased mortality. Whoever else should help to protect them from this risk, various philosophers have argued that any children that they might have will often be among them. Proceeding on this assumption, this article considers what filial duties to protect ageing parents from loneliness consist of, or might consist of. I develop my answer by showing that a view that may be intuitively plausible, namely that they simply require children to visit their ageing parents regularly when they can do so at reasonable cost and call, text, and/or email them from time to time, is defective in three respects. First, it ignores children’s potential responsibilities to encourage and/or facilitate social interaction between their parents and third parties. Second, it ignores their potential responsibilities to help provide their parents with non-human companionship. Third, it elides over their duties to coordinate their efforts to offer loneliness protection with others. What I end up proposing instead, then, is an approach for protecting ageing parents from loneliness that is multi-faceted.
Molecular diagnosis of diffuse glioma using a chip-based digital PCR system to analyze IDH, TERT, and H3 mutations in the cerebrospinal fluid
Authors: Fujioka Yutaka , Hata Nobuhiro , Akagi Yojiro , Kuga Daisuke , Hatae Ryusuke , Sangatsuda Yuhei , Michiwaki Yuhei , Amemiya Takeo , Takigawa Kosuke , Funakoshi Yusuke , Sako Aki , Iwaki Toru , Iihara Koji , Mizoguchi Masahiro
Published: January 2021

Purpose

Conventional genetic analyzers require surgically obtained tumor tissues to confirm the molecular diagnosis of diffuse glioma. Recent technical breakthroughs have enabled increased utilization of cell-free tumor DNA (ctDNA) in body fluids as a reliable resource for molecular diagnosis in various cancers. Here, we tested the application of a chip-based digital PCR system for the less invasive diagnosis (i.e., liquid biopsy) of diffuse glioma using the cerebrospinal fluid (CSF).

Methods

CSF samples from 34 patients with diffuse glioma were collected from the surgical field during craniotomy. Preoperative lumbar CSF collection was also performed in 11 patients. Extracted ctDNA was used to analyze diagnostic point mutations in IDH1 R132H, TERT promoter (C228T and C250T), and H3F3A (K27M) on the QuantStudio® 3D Digital PCR System. These results were compared with their corresponding tumor DNA samples.

Results

We detected either of the diagnostic mutations in tumor DNA samples from 28 of 34 patients. Among them, we achieved precise molecular diagnoses using intracranial CSF in 20 (71%). Univariate analyses revealed that the World Health Organization (WHO) grade (p = 0.0034), radiographic enhancement (p = 0.0006), and Mib1 index (p = 0.01) were significant predictors of precise CSF-based molecular diagnosis. We precisely diagnosed WHO grade III or IV diffuse gliomas using lumbar CSF obtained from 6 (87%) of 7 patients with tumors harboring any mutation.

Conclusion

We established a novel, non-invasive molecular diagnostic method using a chip-based digital PCR system targeting ctDNA derived from CSF with high sensitivity and specificity, especially for high-grade gliomas.
Land use and land cover dynamics in Leiria City: relation between peri-urbanization processes and hydro-geomorphologic disasters
Authors: Barros José Leandro , Tavares Alexandre Oliveira , Santos Pedro Pinto
Published: January 2021

The objective of the present study is to evaluate the relation between the spatial and temporal dynamics of Land Use and Land Cover (LULC) and the hydro-geomorphological processes and their impacts. The study area is the city of Leiria, in central Portugal, within the period 1958–2018 based on the historical record of floods and landslides disasters. The LULC analysis shows an accentuated increase in the artificial areas and a continuous decrease in the agricultural areas. With regard to hydro-geomorphologic disaster occurrences, a total of 124 occurrences were identified, having caused a set of impacts. The obtained results allow one to characterize the artificialization process, its intensity and territorial dispersion, as a consequence of urban sprawl and peri-urbanization, along with its consequences in exposure to hydro-geomorphological processes. The analysis concludes that changing the risk drivers resulted in an increase in frequency and spatial dispersion of hydro-geomorphologic disasters over the analysed period.
A Criterion for the Effective Work of Adhesion in Loading and Unloading of Adhesive Soft Solids from Rough Surfaces
Authors: Papangelo Antonio , Ciavarella Michele
Published: January 2021

Recently, Dalvi and co-authors have shown detailed experimental data of adhesion of soft spheres with rough substrates with roughness measured down to almost the atomic scale, finding that the Persson and Tosatti theory gave satisfactory predictions of the apparent work of adhesion during loading, once the increase of the surface area due to roughness is correctly computed at extremely small scales. We show that unloading data would show similar correlation with the Persson–Tosatti’s simple criterion, but for a much larger effective work of adhesion, which therefore becomes not an “intrinsic” property. This suggests either strong hysteresis even at apparently very low peeling velocities or the need to use a criterion that has different behavior during loading and unloading. We attempt this inspired by the results of Guduru for a simple case of axisymmetric waviness, and a much better fit of the experimental data by Dalvi and co-authors is obtained using the entire set of data at loading and unloading, even assuming a single work of adhesion value. However, we cannot rule out that both (viscoelastic) and (roughness-induced) enhancement effects coexist in these data.
Larry Alexander and Kimberly Kessler Ferzan on Omissions and Normative Ignorance: A Critical Reply
Authors: Husak Douglas
Published: January 2021

Reflections on Crime and Culpability seeks to elaborate, extend, and occasionally qualify the insights reached by Larry Alexander and Kim Ferzan in their influential prior collaboration, Crime and Culpability. They deftly explore any number of new issue that all criminal theorists should be encouraged to address. In my essay, I discuss and challenge their positions on omissions as well as on moral ignorance. Their treatment of the latter issue is a clear improvement over that in their earlier book. But their views on omissions suggest to me that they should have had reservations about some of the most fundamental claims of their overarching theory.
Impulskontrollstörungen in der ICD-11
Authors: Bründl Susanne , Fuss Johannes
Published: January 2021

Dieser Beitrag beschäftigt sich mit der Neuerung der Diagnoserichtlinien in der 11. Revision der International Classification of Diseases and Related Health Problems (ICD-11) im Kapitel der Impulskontrollstörungen. Die Diagnosen Pyromanie und Kleptomanie bleiben nahezu unverändert erhalten. Die Diagnose pathologisches Glücksspiel verliert ihren Status als Impulskontrollstörung und wird Teil des neuen Kapitels der Verhaltenssüchte. Neu im Kapitel der Impulskontrollstörungen ist die Wiederaufnahme der Diagnose intermittierende explosible Störung sowie die neue, kontrovers diskutierte Diagnose zwanghafte sexuelle Verhaltensstörung. Der Artikel stellt Änderungen der Diagnosen zwischen der ICD-11 und ihrer Vorgängerversion (ICD-10) gegenüber, greift aktuelle Diskussionen rund um das Kapitel der Impulskontrollstörungen auf und beschreibt klinische sowie forensisch relevante Implikationen der modifizierten und neu eingeführten Diagnosen.
A Feasibility Study of a One-to-One Mindfulness-Based Intervention for Improving Mood in Stroke Survivors
Authors: Wrapson Wendy , Dorrestein Marlies , Wrapson Jill , Theadom Alice , Kayes Nicola M. , Snell Deborah L. , Rutherford Sandy , Roche Maree , Babbage Duncan R. , Taylor Steve , Siegert Richard J.
Published: January 2021

Objectives

Mindfulness is an evidence-based treatment for depression but has never been rigorously tested with stroke survivors with depression. This feasibility study examined several issues relevant to a potential trial of a mindfulness-based intervention (MBI) for improving mood after stroke.

Methods

In 2017–2019 in New Zealand, we recruited 20 stroke survivors with low mood to undergo a 6-week, one-on-one MBI course delivered by an occupational therapist experienced in MBIs. Pre, post, and 4-week follow-up assessments were completed.

Results

Fifteen participants completed all six sessions and a 4-week “booster” or top-up session. The 1-hour session duration was considered appropriate by participants and all enjoyed the face-to-face individualized format. Mean Beck Depression Inventory-II scores improved by more than one standard deviation and this was maintained at follow-up. However, the baseline assessment package was too long for some participants due to the cognitive component. Three participants indicated feeling emotionally challenged by some of the practices. These effects were managed by the mindfulness facilitator by adjusting the practice, so participants maintained their sense of agency, well-being, and overall benefit from the program.

Conclusions

MBI training delivered individually over six weekly sessions was acceptable to stroke survivors with 14/15 participants reporting improved mood. Three participants reported feeling emotionally challenged by some of the practices and we recommend MBIs for stroke survivors be provided by practitioners experienced in mindfulness, working with stroke, and trauma-informed therapy. It is important now to conduct rigorous randomized controlled trials to test the effectiveness and efficacy of MBIs for stroke survivors.
Estimation Under Mode Effects and Proxy Surveys, Accounting for Non-ignorable Nonresponse
Authors: Pfeffermann Danny , Preminger Arie
Published: January 2021

We propose a new, model-based methodology to address two major problems in survey sampling: The first problem is known as mode effects, under which responses of sampled units possibly depend on the mode of response, whether by internet, telephone, personal interview, etc. The second problem is of proxy surveys, whereby sampled units respond not only about themselves but also for other sampled. For example, in many familiar household surveys, one member of the household provides information for all other members, possibly with measurement errors. Ignoring the existence of mode effects and/or possible measurement errors in proxy surveys could result in possible bias in point estimators and subsequent inference. Our approach accounts also for nonignorable nonresponse. We illustrate the proposed methodology by use of simulation experiments and real sample data, with known true population values.
New analytical model of elastic-plastic contact for three-dimensional rough surfaces considering interaction of asperities
Authors: Wen Yuqin , Tang Jinyuan , Zhou Wei , Li Lin , Zhu Caichao
Published: January 2021

The contact calculation of three-dimensional real rough surfaces is the frontier field of tribology and surface science. In this study, we consider the interaction and elastic-plastic deformation characteristics of asperities and further, propose an analytical contact calculation method for rough surfaces considering the interaction of asperities. Based on the watershed algorithm, the rough surface is segmented and the asperities are reconstructed into ellipsoids. According to the height relationship between the asperities, the definition of the deformation reference height of the matrix between each couple of asperities is provided. Subsequently, the calculation formula of the substrate deformation is provided according to the local contact pressure considering the elastic-plastic deformation of the asperity, and the contact state under a specific load is determined using the iterative correction method. The results correspond with those of finite element numerical calculation and the study reveals the following: (1) compared with the results obtained without considering the asperity interaction, contact area, distance, and stiffness will be reduced by 6.6%, 19.6%, and 49.5%, respectively, when the influence of asperity interaction is considered; (2) the interaction of the asperities has the greatest influence on the surface contact distance and stiffness. Under the same load, the existence of asperity interaction will reduce the contact distance, area, and stiffness; (3) considering the interaction of the asperities, the higher asperity will bear more load, but it will simultaneously reduce the contact of the surrounding area and increase that of the distant area. The calculation method proposed in this study has the advantages of high calculation efficiency and accuracy, thus, providing the calculation basis and method for subsequent studies on service performance of rough surfaces, such as the calculation of contact stiffness and fatigue performance analysis of rough surfaces.
Adhesion and friction performance of DLC/rubber: The influence of plasma pretreatment
Authors: Bai Changning , Gong Zhenbin , An Lulu , Qiang Li , Zhang Junyan , Yushkov Georgy , Nikolaev Alexey , Shandrikov Maxim , Zhang Bin
Published: January 2021

Diamond-like carbon (DLC) films are deposited on rubber surfaces to protect the rubber components, and surface pretreatment of the rubber substrates prior to the film deposition can improve the adhesion between the DLC films and the rubber. Thus, the principal purpose of this work concentrates on determining the effects of argon (Ar), oxygen (O2), nitrogen (N2), and hydrogen (H2) plasma pretreatments on the adhesion and friction performance of the DLC films deposited on rubber (DLC/rubber). The results indicated that the Ar plasma pretreatment promoted the formation of a compact layer on the rubber surface. By contrast, massive fillers were exposed on the rubber surface after oxygen or nitrogen plasma pretreatments. Moreover, the typical micrometer-scale patches divided by random cracks were observed on the surface of DLC/rubber, except for the sample pretreated with oxygen plasma. The adhesion of DLC/rubber was found to strengthen with the removal of weak boundary layers and the generation of free radicals on the rubber surface after plasma pretreatment. The tribo-tests revealed that DLC/rubber with O2, N2, and H2 plasma pretreatments cannot achieve optimal friction performance. Significantly, DLC/rubber with Ar plasma pretreatment exhibited a low and stable friction coefficient of 0.19 and superior wear resistance, which was correlated to the high adhesion, good load-bearing of the rubber surface, and the approximate sine function of the surface profile of the DLC film.
Toxoplasma gondii and Psychopathology: Latent Infection Is Associated with Interpersonal Sensitivity, Psychoticism, and Higher Testosterone Levels in Men, but Not in Women
Authors: Borráz-León Javier I. , Rantala Markus J. , Luoto Severi , Krams Indrikis , Contreras-Garduño Jorge , Cerda-Molina Ana Lilia , Krama Tatjana
Published: January 2021

Objective

The ability of parasites to hijack the nervous system, manipulating the host’s physiology and behavior in ways that enhance the parasite’s fitness while damaging host fitness, is a topic of ongoing research interest in evolutionary biology, but is largely overlooked in mental health research. Nevertheless, recent evidence has shown that Toxoplasma gondii infection can change host testosterone levels and influence the development of some psychiatric disorders. Here, we tested this hypothesis in a mixed sample of 213 non-clinical subjects.

Methods

Participants (nmales = 108, nfemales = 105) provided 5 ml of blood to quantify testosterone levels and Toxoplasma gondii antibodies. The Symptom Checklist-90-Revised was used to assess psychopathological symptoms.

Results

The results showed that Toxoplasma-infected men had higher testosterone levels and scored higher in Interpersonal Sensitivity and Psychoticism symptoms than non-infected men. Toxoplasma-infected women did not differ from control women.

Conclusions

Framed in an evolutionary framework, the findings suggest that the elevated testosterone levels and the expression of psychopathological symptoms can be seen as the result of the manipulation exerted by Toxoplasma gondii either to reach its definitive host or to increase its spread. Future research can benefit from integrating insights from evolutionary biology and parasite-host interactions with physiology, immunology, and mental health to develop a better understanding of mental health etiology.
The role of pedogenesis and natural fertiliser as vectors for essential metal content in agricultural topsoils, Central India
Authors: Suhr Nils , Widdowson Mike , Kamber Balz S.
Published: January 2021

Essential trace metals are well known for their environmental toxicity and for being part of complex bio-chemical cycles. Their role as critical micronutrients, delivering vital health benefits, is less widely discussed and understood, holding back strategies for combatting malnutrition. Crops grown on many Indian soils suffer from deficiencies in essential metals, notably iron (Fe), zinc (Zn), and molybdenum (Mo). The list of deficient metals will likely grow due to increasing future crop demand. Geostatistical analysis of soils and farmyard manure (FYM), the predominant fertiliser, implies that residual oxide minerals carry high concentrations of the essential trace metals Fe, Zn, copper (Cu), chromium (Cr), nickel (Ni), cobalt (Co), manganese (Mn) not only in soil but also in FYM (especially Fe, Cr, Cu, Co and Ni). A geochemical survey across a road traverse of 600 km, encompassing an area of c. 15,000 km2, was conducted in Central India to evaluate reported essential metal deficiency in key agricultural topsoils. Importantly, our evaluation of the element cycling in this system reveals that despite high bulk concentrations, some key metals remain bio-unavailable. In effect, the existence of refractory (weathering-resistant) oxides is likely a significant factor for deficiency symptoms in the soil–plant-fertiliser cycle. Further, mass balance calculations of the bioavailable pool of metals imply that only Fe and Mn are present in sufficient quantities to combat deficiency problems. Notwithstanding this limitation of FYM, its high organic carbon content, as well as its importance for Zn, Cu and Fe, validates its traditional use to maintain the fertility and physical condition of Indian topsoils.
Evaluating crude whey for bioethanol production using non-Saccharomyces yeast, Kluyveromyces marxianus
Authors: Tesfaw Asmamaw , Oner Ebru Toksoy , Assefa Fassil
Published: January 2021

Ethanol production from non-food substrate is strongly recommended to avoid competition with food production. Whey, which is rich in nutrients, is one of the non-food substrate for ethanol production by Kluyveromyces spp. The purpose of this study was to optimize ethanol from different crude (non-deproteinized, non-pH adjusted, and non-diluted) whey using K. marxianus ETP87 which was isolated from traditional yoghurt. The sterilized and non-sterilized whey were employed for K. marxianus ETP87 substrate to evaluate the yeast competition potential with lactic acid and other microflora in whey. The effect of pH and temperature on ethanol productivity from whey was also investigated. Peptone, yeast extract, ammonium sulfate ((NH4)2SO4), and urea were supplemented to whey in order to investigate the requirement of additional nutrient for ethanol optimization. The ethanol obtained from non-sterilized whey was slightly and statistically lower than sterilized whey. The whey storage at 4 °C didn’t guarantee the constant lactose presence at longer preservation time. Significantly high amount of ethanol was attained from whey without pH adjustment (3.9) even if it was lower than pH controlled (5.0) whey. The thermophilic yeast, K. marxianus ETP87, yielded high ethanol between 30 and 35 °C, and the yeast was able to produce high ethanol until 45 °C, and significantly lower ethanol was recorded at 50 °C. The ammonium sulfate and peptone enhanced ethanol productivity, whereas yeast extract and urea depressed the yeast ethanol fermentation capability. The K. marxianus ETP87, the yeast isolated from traditional yoghurt, is capable of producing ethanol from non-sterilized and non-deproteinized substrates.
Experimental and numerical study on the performance of externally prestressed reinforced high strength concrete beams with openings
Authors: El-Basiouny Ahmed M. , Askar Hamed S. , El-Zoughiby Mohamad E.
Published: January 2021

This study investigates experimentally and numerically the performance of externally prestressed reinforced high strength concrete (HSC) beams with central openings. Seven externally prestressed rectangular HSC beams (six with central openings and a reference solid beam) are loaded incrementally to failure. All the beams have the same dimensions, reinforcement ratio and openings of variable size. Experimentally, the results show that, the appearance of the first flexural crack and the flexural stiffness reduction are largely governed by opening height. In contrast, the opening length greatly affects the presence of the first shear crack and the obtained values of strains in stirrups. Additionally, the opening length and height when combined can affect the strains in top- and bottom-bars and the failure load of the teste beams. Numerically, a three-dimensional nonlinear finite element analysis using ANSYS has been carried-out to analyze seventy (70) externally prestressed HSC beams with central openings. Based on the numerical results, a general formula to predict the ultimate moment is generated and verified. It can be used to predict the load carrying capacity of aging concrete elements with openings retrofitted using external prestressing techniques.
Approximate analytical solution of buckling of multi-damaged column-like structures using a continuous diffused crack model by variational iteration method
Authors: Zhao Xingzhuang
Published: January 2021

Compressive structural members can be locally damaged by overloading, corrosion, car crash and fire. In this work, a continuous diffused crack model is proposed to study the static stability of Euler–Bernoulli rectangular column-like structures under different boundary conditions. The governing differential equation is formulated by adopting a diffused crack model. The powerful variational iteration method is implemented to find the approximate analytical buckling modes and buckling loads based on the buckling response of the intact column. A novel generalized Lagrange multiplier is derived. The proposed method incorporates the effects of the crack width into consideration when deriving the buckling modes. The stability equation allows addressing the influences of multiple damages and can be applied to both concentrated and distributed cracks. The famous Rayleigh–Ritz method is utilized to verify the computed buckling loads. The proposed diffused crack model and the application with VIM is efficient and accurate for handling buckling problems of cracked columns under different boundary conditions.
The interplay of polyoxyethylene (40) stearate surfactant concentration and aging time on the Mesoporous γ-alumina synthesis and appraisal of its catalytic activity
Authors: Bello Abdu Muhammad , Yacob Abdul Rahim
Published: January 2021

An economical and environmentally benign synthesis method remains important in industrial processes. In this work, kaolin an abundant and non-toxic precursor is employed for mesoporous gamma-alumina synthesis. The study explored the consequence of varying polyoxyethylene (40) stearate (PS) surfactant concentration and aging time in the synthesis of mesoporous gamma-alumina with enhancing structural properties. The alumina was characterized using X-Ray Powder Diffraction (XRD), Thermogravimetric-Derivative Thermal Gravimetric (TG-DTG), Fourier Transform Infrared (FTIR), N2 Adsorption–Desorption, Field Emission Scanning Electron Microscopy (FESEM), Solid State 27Al MAS NMR, and X-Ray Fluorescence (XRF). Structural properties and morphology of the mesoporous γ-Al2O3 improved with increasing surfactant amount from 0.45 g to 1.8 g and aging time from 1 to 2 days, then dropped afterward. Accordingly, mesoporous γ-Al2O3 synthesized with 1.8 g PS and age for 2 days (Al-1.8-2) possessed the highest surface area of 319.2 m2/g, a narrow average pore diameter of 2.7 nm, and pore volume of 0.42 cm3/g. Thus, Al-1.8-2 was chosen and doped with 15% NaOH to obtained 15-Na/Al-1.8-2 catalyst. After modification, the basic sites increased, the surface area decreased, and the morphology changed, signifying Na incorporation into the alumina. On application in methanolysis reaction, up to 99.46% biodiesel yield was obtained, demonstrating a very high activity for the catalyst. The tremendous activity of the catalyst can be associated with the enhanced structural properties of the mesostructured gamma-alumina.
Concentration and risk assessment of toxic metals in indoor dust in selected schools in Southeast, Nigeria
Authors: Ugwu Kenechukwu E. , Ofomatah Anthony C.
Published: January 2021

The health risk of students’ exposure to some potentially toxic metals in classroom dusts in Southeast, Nigeria was assessed. Dust particles were collected from classrooms in some public high schools and digested with aqua regia before analysis for selected metals by atomic absorption spectrophotometry. The geoaccumulation index, contamination factor and the pollution load index were assessed from the metal concentrations of the dust. Hazard quotient and cancer risk index were used to estimate the potential health risk of students’ exposure to the metals in the dust. The metal concentrations (mg/kg) were in the ranges of 1.57–175.38 (Cr); 0.93–463.28 (Cu); 31.94.76–6623.41 (Fe); 4.96–143.98 (Ni); 2.64–375.27 (Zn); and 2.35–53.96 (Pb).The geo-accumulation index values showed that all the dust samples were polluted with Fe and Cr; and unpolluted with other metals with few exemptions. The contamination factor values showed that all the schools but one had a low contamination status due to Ni and Cu. There was moderate contamination by Pb at all the schools but two. All the schools had high contamination of Cr and Fe. The pollution load index indicated that the quality of all the classrooms was deteriorated. The calculated values of hazard quotient indicated that ingestion of dust at most of the classrooms would have no significant risk of non-carcinogenic effects on the health of the students. Dermal contact with the dust at all the classrooms would expose students to adverse effects of Fe. There will be adverse effect due to Pb for dermal contact with dust at most of the schools. Ingestion of dust particles at classrooms in all the schools would have carcinogenic effect due to Ni. Correlation analysis indicated that the sources of the metals varied. This study provided baseline data for relevant bodies to use in monitoring and controlling pollution so as to protect students from toxic metals.
Correction to: Thermal hydraulic considerations of nuclear reactor systems: Past, present and future challenges
Authors: Yeoh Guan Heng
Published: January 2021

The article “Thermal hydraulic considerations of nuclear reactor systems: Past, present and future challenges” written by Guan Heng Yeoh, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 08 April 2019 without open access. After publication in Volume 1, Issue 1, page 3–27, the author(s) decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
Correction to: One-dimensional drift-flux correlations for two-phase flow in medium-size channels
Authors: Hibiki Takashi
Published: January 2021

The article “One-dimensional drift-flux correlations for two-phase flow in medium-size channels” written by Takashi Hibiki, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 17 April 2019 without open access. After publication in Volume 1, Issue 2, page 85–100, the author(s) decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
Building socio-hydrological resilience “improving capacity for building a socio hydrological system resilience”
Authors: Javadinejad Safieh , Hannah David , Krause Stefan , Naseri Mohsen , Dara Rebwar , Jafary Forough
Published: January 2021

In response to the climate change, hydrologic and environmental changes and increased uncertainties, implication of water resilience in a context of water governance is essential for improved management. This study aims to answer the following questions: 1) what are different types of resilience with regard to its several definitions, 2) what is the relationship between resilience, trend and performance in water governance. This research applied literature reviews (as theoretical approach) and interviews with local water managers (as experimental approach) to develop better resilient plan under extreme events. This study compared the results of reviewed articles with results that we obtained from interviews with water managers in a case study area in order to develop a resilience planning under extreme events. The research has analyzed the resilience for water management based on theoretical and empirical knowledge and also provided some helpful recommendations for building system resilience for the future. The analysis of the findings shows that sufficient resilience in each society depends considerably on water resources planning (implied by the government) and also resilience in water supply infrastructure (designed by engineers). In addition, in order to get a high level of resilience, integration of ecological knowledge, water supplies, government’s regulation/legislation, engineering projects and humans’ interaction, is necessary. Moreover, the results indicate that failures and hydrologic catastrophes are mainly as a result of big gaps between these elements and also a lack of integrated approach between water-institutions and the environment in water management.
The lifespan of classical solutions for the inviscid Surface Quasi-geostrophic equation
Authors: Castro Ángel , Córdoba Diego , Zheng Fan
Published: January 2021

We consider classical solutions of the inviscid Surface Quasi-geostrophic equation that are a small perturbation
ϵ
from a radial stationary solution

\theta = |x|

. We use a modified energy method to prove the existence time of classical solutions from

\frac{1}{\epsilon }

to a time scale of

\frac{1}{\epsilon ^{4}}

. Moreover, by perturbing in a suitable direction we construct global smooth solutions, via bifurcation, that rotate uniformly in time and space.
The Cosmos
Authors: Pasachoff Jay M. , Filippenko Alex
Published: January 2021

The fifth edition of The Cosmos: Astronomy in the New Millennium provides you with the fundamentals of astronomical knowledge that have been built up over decades, with an expanded discussion of the incredible advances that are now taking place in this fast-paced field, such as New Horizons' flyby of Pluto, exoplanets, 'dark matter', and the direct detection of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO). Written in a clear and easily understandable style, this textbook has been thoroughly revised to include updated data and figures, new images from recent space missions and telescopes, the latest discoveries on supernovae, and new observations of the region around the four-million-solar-mass black hole at the center of our Milky Way Galaxy. A rich array of teaching and learning resources is available at http://thecosmos5.com. The website is regularly updated to include the latest discoveries and photographs in the field.
The Economic Origin of Political Parties
Authors: Kam Christopher , Newson Adlai
Published: January 2021

This Element examines how the changing economic basis of parliamentary elections in nineteenth century England and Wales contributed to the development of modern parties and elections. Even after the 1832 Reform Act expanded the British electorate, elections in many constituencies went uncontested, party labels were nominal, and candidates spent large sums treating and bribing voters. By the end of the century, however, almost every constituency was contested, candidates stood as representatives of national parties, and campaigns were fought on the basis of policies. We show how industrialization, the spread of literacy, and the rise of cheap newspapers, encouraged candidates to enter and contest constituencies. The increased expense that came from fighting frequent elections in larger constituencies induced co-partisan candidates to form slates. This imparted a uniform partisan character to parliamentary elections that facilitated the emergence of programmatic political parties.
Attitudes and Preparedness of Non-Frontline Physicians in Saudi Arabia Toward the COVID-19 Pandemic
Authors: Malaekah Haifaa , Aljahany Muna , Alassaf Wajdan , Alotaibi Malak , Alsaffar Mashael
Published: January 2021

Objective:

This study assesses the attitudes (willingness) and preparedness of non-frontline physicians across different specialties in the Kingdom of Saudi Arabia (KSA) toward the management of hospitalized coronavirus disease (COVID-19) patients.

Methods:

This cross-sectional study conducted between April 15, 2020, and May 5, 2020, included 6209 physicians working in KSA. An electronic questionnaire was designed and validated for the assessment of 3 categorical outcome variables, namely, attitudes, confidence, and knowledge levels. Pearson’s chi-square test was used for comparing the distribution of the proportions of these 3 categorical variables.

Results:

Most participants (63.2%) were willing and prepared to treat COVID-19 patients. A significantly large proportion of participants specializing in anesthesiology (78.2%) had higher knowledge levels, followed by those from plastic surgery (71.1%), pediatrics (69.7%), and obstetrics and gynecology (69.1%) (P< 0.0001). Lower confidence levels were found for airway management skills (38.1%), particularly among dermatologists and radiologists.

Conclusion:

Higher knowledge levels about personal protective equipment (PPE) use and confidence in airway management skills were proportionally related to the level of willingness to participate in COVID-19 patient management. There is an urgent need to train doctors from certain specialties on PPE use and airway management to enable their frontline support of severely ill COVID-19 patients.
Brill-Noether theory for curves of a fixed gonality
Authors: Jensen David , Ranganathan Dhruv
Published: January 2021

We prove a generalisation of the Brill-Noether theorem for the variety of special divisors$W^r_d(C)$on a general curveCof prescribed gonality. Our main theorem gives a closed formula for the dimension of$W^r_d(C)$. We build on previous work of Pflueger, who used an analysis of the tropical divisor theory of special chains of cycles to give upper bounds on the dimensions of Brill-Noether varieties on such curves. We prove his conjecture, that this upper bound is achieved for a general curve. Our methods introduce logarithmic stable maps as a systematic tool in Brill-Noether theory. A precise relation between the divisor theory on chains of cycles and the corresponding tropical maps theory is exploited to prove new regeneration theorems for linear series with negative Brill-Noether number. The strategy involves blending an analysis of obstruction theories for logarithmic stable maps with the geometry of Berkovich curves. To show the utility of these methods, we provide a short new derivation of lifting for special divisors on a chain of cycles with generic edge lengths, proved using different techniques by Cartwright, Jensen, and Payne. A crucial technical result is a new realisability theorem for tropical stable maps in obstructed geometries, generalising a well-known theorem of Speyer on genus$1$curves to arbitrary genus.
Reflecting laser-driven shocks in diamond in the megabar pressure range
Authors: Jakubowska K. , Mancelli D. , Benocci R. , Trela J. , Errea I. , Martynenko A. S. , Neumayer P. , Rosmej O. , Borm B. , Molineri A. , Verona C. , Cannatà D. , Aliverdiev A. , Roman H. E. , Batani D.
Published: January 2021

In this work we present experimental results on the behavior of diamond at megabar pressure. The experiment was performed using the PHELIX facility at GSI in Germany to launch a planar shock into solid multi-layered diamond samples. The target design allows shock velocity in diamond and in two metal layers to be measured as well as the free surface velocity after shock breakout. As diagnostics, we used two velocity interferometry systems for any reflector (VISARs). Our measurements show that for the pressures obtained in diamond (between 3 and 9 Mbar), the propagation of the shock induces a reflecting state of the material. Finally, the experimental results are compared with hydrodynamical simulations in which we used different equations of state, showing compatibility with dedicated SESAME tables for diamond.
SHORTENING CLOPEN GAMES
Authors: AGUILERA JUAN P.
Published: January 2021

For every countable wellordering
$\alpha $
greater than
$\omega $
, it is shown that clopen determinacy for games of length
$\alpha $
with moves in
$\mathbb {N}$
is equivalent to determinacy for a class of shorter games, but with more complicated payoff. In particular, it is shown that clopen determinacy for games of length
$\omega ^2$
is equivalent to
$\sigma $
-projective determinacy for games of length
$\omega $
and that clopen determinacy for games of length
$\omega ^3$
is equivalent to determinacy for games of length
$\omega ^2$
in the smallest
$\sigma $
-algebra on
$\mathbb {R}$
containing all open sets and closed under the real game quantifier.