bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulating AI: Considerations that Apply Across Domains
Authors: Kane Angela
Published: February 2021

Awareness that AI-based technologies have far outpaced the existing regulatory frameworks have raised challenging questions about how to set limits on the most dangerous developments (lethal autonomous weapons or surveillance bots, for instance). Under the assumption that the robotics industry cannot be relied on to regulate itself, calls for government intervention within the regulatory space—national and international—have multiplied. The various approaches to regulating AI fall into two main categories. A sectoral approach looks to identify the societal risks posed by individual technologies, so that preventive or mitigating strategies can be implemented, on the assumption that the rules applicable to AI, in say the financial industry, would be very different from those relevant to heath care providers. A cross-sectoral approach, by contrast, involves the formulation of rules (whether norms adopted by industrial consensus or laws set down by governmental authority) that, as the name implies, would have application to AI-based technologies in their generality. After surveying some domestic and international initiatives that typify the two approaches, the chapter concludes with a list of 15 recommendations to guide reflection on the promotion of societally beneficial AI.
Foundations of Artificial Intelligence and Effective Universal Induction
Authors: Zimmermann Jörg , Cremers Armin B.
Published: February 2021

The term Artificial Intelligence was coined in 1956. Since then, this new research area has gone through several cycles of fast progress and periods of apparent stagnation. Today, the field has broadened and deepened significantly, and developed a rich variety of theoretical approaches and frameworks on the one side, and increasingly impressive practical applications on the other side. While a thorough foundation for a general theory of cognitive agents is still missing, there is a line of development within AI research which aims at foundational justifications for the design of cognitive agents, enabling the derivation of theorems characterizing the possibilities and limitations of computational cognitive agents.
„… oder doch lieber daheimbleiben?“ – Unterstützung bei der Entscheidung zur Inanspruchnahme der Regelversorgung während der COVID-19-Pandemie durch Akteure des Gesundheitssystems
Authors: Bitzer Eva Maria , Ansmann Lena , Hörold Madlen , Lyssenko Lisa , Apfelbacher Christian
Published: February 2021

Hintergrund

In der COVID-19-Pandemie ging die Versorgung nichtübertragbarer Erkrankungen zeitweise deutlich zurück, auch weil Menschen Angst vor einer Ansteckung hatten. Wir führen eine Bestandsaufnahme zur organisationalen Gesundheitskompetenz in der Regelversorgung nichtübertragbarer Erkrankungen in der ersten Welle der COVID-19-Pandemie durch und fragen: Inwiefern wurden Menschen mit gesundheitlichen Beschwerden dabei unterstützt, gesundheitskompetente Entscheidungen für oder gegen die Inanspruchnahme von Versorgungsleistungen zu treffen?

Methodik

Strukturierende Inhaltsanalyse der Internetpräsenzen der Mitglieder der Arbeitsgemeinschaft der Wissenschaftlich Medizinischen Fachgesellschaften (AWMF; n = 179), der kassen(zahn)ärztlichen Vereinigungen (K(Z)Ven; n = 38), ausgewählter Krankenkassen (n = 21), ausgewählter Behandlungseinrichtungen (n = 25) und überregionaler Anbieter von Gesundheitsinformationen (n = 5) zu Informationen und Angeboten zum Thema.

Ergebnisse

Die geprüften Internetpräsenzen informieren weitgehend rund um COVID-19, aber nur selten darüber, wie man sich bei einer (vermuteten) anderen Erkrankung in Bezug auf die Inanspruchnahme von Versorgungsleistungen verhält. 2 Portale von Anbietern von Gesundheitsinformationen, eine Krankenkasse, aber keine der KVen bieten explizite Entscheidungshilfen an. KVen weisen öfter, aber nicht durchgängig auf die generelle Möglichkeit von Videosprechstunden hin.

Diskussion

Für die meisten Patient*innen gab es damit keine gezielten Informationen zu dem Thema. Angesichts der Fortdauer der COVID-19-Pandemie gilt es, vorhandene vertrauenswürdige, qualitativ hochwertige Informations- und Beratungskapazitäten auszubauen und ihre Bekanntheit zu erhöhen, um gesundheitskompetente Entscheidungen auch in der Pandemie zu ermöglichen.
Effect of pluronic block polymers and N-acetylcysteine culture media additives on growth rate and fatty acid composition of six marine microalgae species
Authors: Sauvage Justine , Wikfors Gary H. , Li Xiaoxu , Gluis Mark , Nevejan Nancy , Sabbe Koen , Joyce Alyssa
Published: February 2021

The efficiency of microalgal biomass production is a determining factor for the economic competitiveness of microalgae-based industries. N-acetylcysteine (NAC) and pluronic block polymers are two compounds of interest as novel culture media constituents because of their respective protective properties against oxidative stress and shear-stress-induced cell damage. Here we quantify the effect of NAC and two pluronic (F127 and F68) culture media additives upon the culture productivity of six marine microalgal species of relevance to the aquaculture industry (four diatoms-Chaetoceros calcitrans,Chaetoceros muelleri,Skeletonema costatum, andThalassiosira pseudonana; two haptophytes-Tisochrysis luteaandPavlova salina). Algal culture performance in response to the addition of NAC and pluronic, singly or combined, is dosage- and species-dependent. Combined NAC and pluronic F127 algal culture media additives resulted in specific growth rate increases of 38%, 16%, and 24% forC. calcitrans,C. muelleri, andP. salina, respectively. Enhanced culture productivity for strains belonging to the genusChaetoceroswas paired with an ~27% increase in stationary-phase cell density. For some of the species examined, culture media enrichments with NAC and pluronic resulted in increased omega-3-fatty acid content of the algal biomass. Larval development (i.e., growth and survival) of the Pacific oyster (Crassostrea gigas) was not changed when fed a mixture of microalgae grown in NAC- and F127-supplemented culture medium. Based upon these results, we propose that culture media enrichment with NAC and pluronic F127 is an effective and easily adopted approach to increase algal productivity and enhance the nutritional quality of marine microalgal strains commonly cultured for live-feed applications in aquaculture.

Key points

• Single and combined NAC and pluronic F127 culture media supplementation significantly enhanced the productivity of Chaetoceros calcitrans and Chaetoceros muelleri cultures.

• Culture media enrichments with NAC and F127 can increase omega-3-fatty acid content of algal biomass.

• Microalgae grown in NAC- and pluronic F127-supplemented culture media are suitable for live-feed applications.
Elotuzumab for the treatment of extramedullary myeloma: a retrospective analysis of clinical efficacy and SLAMF7 expression patterns
Authors: Danhof Sophia , Rasche Leo , Mottok Anja , Steinmüller Tabea , Zhou Xiang , Schreder Martin , Kilian Teresa , Strifler Susanne , Rosenwald Andreas , Hudecek Michael , Einsele Hermann , Gerhard-Hartmann Elena
Published: February 2021

Extramedullary disease (EMD) represents a high-risk state of multiple myeloma (MM) associated with poor prognosis. While most anti-myeloma therapeutics demonstrate limited efficacy in this setting, some studies exploring the utility of chimeric antigen receptor (CAR)-modified T cells reported promising results. We have recently designed SLAMF7-directed CAR T cells for the treatment of MM. SLAMF7 is a transmembrane receptor expressed on myeloma cells that plays a role in myeloma cell homing to the bone marrow. Currently, the only approved anti-SLAMF7 therapeutic is the monoclonal antibody elotuzumab, but its efficacy in EMD has not been investigated thoroughly. Thus, we retrospectively analyzed the efficacy of elotuzumab-based combination therapy in a cohort of 15 patients with EMD. Moreover, since the presence of the target antigen is an indispensable prerequisite for effective targeted therapy, we investigated the SLAMF7 expression on extramedullary located tumor cells before and after treatment. We observed limited efficacy of elotuzumab-based combination therapies, with an overall response rate of 40% and a progression-free and overall survival of 3.8 and 12.9 months, respectively. Before treatment initiation, all available EMD tissue specimens (n = 3) demonstrated a strong and consistent SLAMF7 surface expression by immunohistochemistry. Furthermore, to investigate a potential antigen reduction under therapeutic selection pressure, we analyzed samples of de novo EMD (n = 3) outgrown during elotuzumab treatment. Again, immunohistochemistry documented strong and consistent SLAMF7 expression in all samples. In aggregate, our data point towards a retained expression of SLAMF7 in EMD and encourage the development of more potent SLAMF7-directed immunotherapies, such as CAR T cells.
Same-day discharge after appendectomy for acute appendicitis: a systematic review and meta-analysis
Authors: de Wijkerslooth Elisabeth M. L. , Bakas Jay M. , van Rosmalen Joost , van den Boom Anne Loes , Wijnhoven Bas P. L.
Published: February 2021

Purpose

Patients presenting with acute appendicitis are usually hospitalized for a few days for appendectomy and postoperative recovery. Shortening length of stay may reduce costs and improve patient satisfaction. The purpose of this study was to assess the safety of same-day discharge after appendectomy for acute appendicitis.

Methods

A systematic review was performed according to PRISMA guidelines. A literature search of EMBASE, Ovid MEDLINE, Web of Science, Cochrane Central, and Google Scholar was conducted from inception to April 14, 2020. Two reviewers independently screened the literature and selected studies that addressed discharge on the same calendar day as the appendectomy. Risk of bias was assessed with the ROBINS-I tool. Main outcomes were hospital readmission, complications, and unplanned hospital visits in the postoperative course. A random effects model was used to pool risk ratios for the main outcomes.

Results

Of the 1912 articles screened, 17 comparative studies and 8 non-comparative studies met the inclusion criteria. Most only included laparoscopic procedure for uncomplicated appendicitis. Most studies were considered at moderate or serious risk of bias. In meta-analysis, same-day discharge (vs. overnight hospitalization) was not associated with increased rates of readmission, complication, and unplanned hospital visits. Non-comparative studies demonstrated low rates of readmission, complications, and unplanned hospital visits after same-day discharge.

Conclusion

This study suggests that same-day discharge after laparoscopic appendectomy for uncomplicated appendicitis is safe without an increased risk of readmission, complications, or unplanned hospital visits. Hence, same-day discharge may be further encouraged in selected patients.

Trial registration

PROSPERO registration no. CRD42018115948
Effect of method of administration on the oral health–related quality of life assessment using the Early Childhood Oral Health Impact Scale (ECOHIS-G)
Authors: Bekes Katrin , Solanke Cia , Waldhart Tessa , Priller Julia , Stamm Tanja
Published: February 2021

Objectives

The influence of the administration method used to collect oral health–related quality of life (OHRQoL) in children remains largely unknown. The aim of this study was to determine whether the OHRQoL information obtained using the Early Childhood Oral Health Impact Scale (ECOHIS) differed with different methods of data collection (face-to-face interview, telephone, or self-administered questionnaire).

Materials and methods

The OHRQoL of 38 preschool children, aged 1 to 5 years, was measured using the German version of the ECOHIS. The instrument was administered to the caregivers of these children using three different methods, with an interval of 1 week between each administration. Test-retest reliability for the repeated ECOHIS-G assessments across the three methods of administration, agreement, and convergent validity was determined.

Results

Kappa coefficients for agreement between two different methods of administration, respectively, ranged from moderate to substantial (0.47 to 0.65). Test-retest reliability was moderate (ICC 0.65–0.79).

Conclusion

In conclusion, the three methods of administration (face-to-face interview, telephone interview, or self-administered questionnaire) of the ECOHIS-G were comparable in 1- to 5-year-old preschool children.

Clinical relevance

All three methods of administration can be used to obtain valid and reliable OHRQoL information in German speaking countries.
Curve Based Approximation of Measures on Manifolds by Discrepancy Minimization
Authors: Ehler Martin , Gräf Manuel , Neumayer Sebastian , Steidl Gabriele
Published: February 2021

The approximation of probability measures on compact metric spaces and in particular on Riemannian manifolds by atomic or empirical ones is a classical task in approximation and complexity theory with a wide range of applications. Instead of point measures we are concerned with the approximation by measures supported on Lipschitz curves. Special attention is paid to push-forward measures of Lebesgue measures on the unit interval by such curves. Using the discrepancy as distance between measures, we prove optimal approximation rates in terms of the curve’s length and Lipschitz constant. Having established the theoretical convergence rates, we are interested in the numerical minimization of the discrepancy between a given probability measure and the set of push-forward measures of Lebesgue measures on the unit interval by Lipschitz curves. We present numerical examples for measures on the 2- and 3-dimensional torus, the 2-sphere, the rotation group on$$\mathbb R^3$$R3and the Grassmannian of all 2-dimensional linear subspaces of$${\mathbb {R}}^4$$R4. Our algorithm of choice is a conjugate gradient method on these manifolds, which incorporates second-order information. For efficient gradient and Hessian evaluations within the algorithm, we approximate the given measures by truncated Fourier series and use fast Fourier transform techniques on these manifolds.
Heterogeneous snowpack response and snow drought occurrence across river basins of northwestern North America under 1.0°C to 4.0°C global warming
Authors: Shrestha Rajesh R. , Bonsal Barrie R. , Bonnyman James M. , Cannon Alex J. , Najafi Mohammad Reza
Published: February 2021

Anthropogenic climate change is affecting the snowpack freshwater storage, with socioeconomic and ecological impacts. We present an assessment of maximum snow water equivalent (SWEmax) change in large river basins of the northwestern North America region using the Canadian Regional Climate Model 50-member ensemble under 1.0 °C to 4.0 °C global warming thresholds above the pre-industrial period. The projections indicate steep SWEmax decline in the warmer coastal/southern basins (i.e., Skeena, Fraser and Columbia), moderate decline in the milder interior basins (i.e., Peace, Athabasca and Saskatchewan), and either a small increase or decrease in the colder northern basins (i.e., Yukon, Peel, and Liard). A key factor for these spatial differences is the proximity of winter mean temperature to the freeze/melt threshold, with larger SWEmax declines for the basins closer to the threshold. Using the random forests machine-learning model, we find that the SWEmax change is primarily temperature controlled, especially for warmer basins. Further, under a categorical framework of below-normal SWEmax defined as snow drought (SD), we find that above-normal temperature and precipitation are the dominant conditions for SD occurrences under higher global warming thresholds. This implies a limited capacity of precipitation increase to compensate the temperature-driven snowpack decline. Additionally, the frequency and severity of SD occurrences are projected to be most extreme in the southern basins where current water demands are highest. Overall, the results of this study, including insights on snowpack changes, their climatic controls, and the framework for SD classification, are applicable for basins spanning a range of hydro-climatological regimes.
Medial clavicle fracture with bone destruction after radical neck dissection combined with postoperative chemotherapy for secondary cervical lymph node metastasis of tongue cancer: a case report
Authors: Tashiro Masayasu , Sano Tomoaki , Sugiura Kazutaka , Minamida Yasuhito , Abiko Yoshihiro , Nagayasu Hiroki , Nakayama Eiji
Published: February 2021

Background

Clavicle fractures (CF) after radical neck dissection (RND) for oral cancer are rare but are thought to occur as a result of myotonia and decreased blood supply to the muscles around the clavicle after RND. The current report presents a rare case of a non-neoplastic pathological CF after RND, and discusses the role of imaging examinations for the timely detection of CF.

Case report

An 82-year-old Japanese man underwent RND followed by chemotherapy without radiotherapy for secondary metastasis of the right cervical lymph node after resection of tongue cancer. Computed tomography at 6 months after RND revealed a fracture with bone destruction in the proximal end of the right clavicle. He had no history of trauma at the site of the fracture and no symptoms. The possibility of bone metastasis of the clavicle was considered; however, the bone destruction had not advanced 6 years after the discovery of the fracture. The CF was thus finally considered to be a side effect of RND, rather than metastasis.

Conclusion

CF is a rare complication following treatment for head and neck cancer but can be caused by neck dissection. Regular imaging examinations, including the clavicular region, are therefore needed before and after surgery to ensure the timely detection of CF.
Are the 50’s, the transition decade, in choroid plexus aging?
Authors: Tahira Ana , Marques Fernanda , Lisboa Bianca , Feltrin Arthur , Barbosa André , de Oliveira Kátia Cristina , de Bragança Pereira Carlos Alberto , Leite Renata , Grinberg Lea , Suemoto Claudia , de Lucena Ferretti-Rebustini Renata Eloah , Pasqualucci Carlos Augusto , Jacob-Filho Wilson , Brentani Helena , Palha Joana Almeida
Published: February 2021

The choroid plexus (CP) is an important structure for the brain. Besides its major role in the production of cerebrospinal fluid (CSF), it conveys signals originating from the brain, and from the circulatory system, shaping brain function in health and in pathology. Previous studies in rodents have revealed altered transcriptome both during aging and in various diseases of the central nervous system, including Alzheimer’s disease. In the present study, a high-throughput sequencing of the CP transcriptome was performed in postmortem samples of clinically healthy individuals aged 50’s through 80’s. The data shows an age-related profile, with the main changes occurring in the transition from the 50’s to the 60’s, stabilizing thereafter. Specifically, neuronal and membrane functions distinguish the transcriptome between the 50’s and the 60’s, while neuronal and axon development and extracellular structure organization differentiate the 50’s from the 70’s. These findings suggest that changes in the CP transcriptome occur early in the aging process. Future studies will unravel whether these relate with processes occurring in late- onset brain diseases.
A colonial cash cow: the return on investments in British Malaya, 1889–1969
Authors: Rönnbäck Klas , Broberg Oskar , Galli Stefania
Published: February 2021

Historical rates of return on investments have received increasing scholarly attention in recent years. Much literature has focused especially on colonies, where institutions have been argued to facilitate severe exploitation. In the present study, we examine the return on investments in an Asian colony, British Malaya, from 1889 to 1969 for a large sample of companies. Our results suggest that the return on investments in Malaya might have been among the highest in the world during the period studied. Nevertheless, this finding fits badly with theories of imperial exploitation and can only to a limited extent be explained by a higher risk premium. Instead, we argue that the main driver of the very high return on investments in Malaya was rather the substantial rise in global market prices of the output of the two main sectors of the Malayan economy, rubber and tin. The way that the process of decolonization unfolded in Malaya did, furthermore, not lead to any major nationalization of foreign-held assets, and did thereby not disrupt the return on investment in the region in the same way as decolonization did to the return on investment in some other colonies.
Lumbar spine bone mineral density and trabecular bone score-adjusted FRAX, but not FRAX without bone mineral density, identify subclinical carotid atherosclerosis
Authors: Pepe J. , Della Grotta G. , Santori R. , De Martino V. , Occhiuto M. , Cilli M. , Minisola S. , Cipriani C.
Published: February 2021

Purpose

Osteoporosis and atherosclerosis share common risk factors. Aim of this study was to test if FRAX (which is an algorithm that can identify subjects at risk of fracture), without or with BMD values, also adjusted for trabecular bone score (TBS) was able to identify subclinical atherosclerosis, evaluated by measurement of carotid intima media thickness (cIMT ≥ 0.9 mm) as compared to DXA values.

Methods

Ninety postmenopausal women underwent DXA measurement and cIMT evaluation. For each patient, the FRAX algorithm for major osteoporotic fracture (M) and for hip fracture (H) without BMD was computed, together with FRAX with BMD and TBS-adjusted FRAX. Serum levels of osteoprotegerin, sRANKL, and interleukin-6 were also measured.

Results

There were no differences in anthropometric parameters and cardiovascular risk factors between subjects with cIMT ≥ 0.9 mm (35% of subjects, group A) compared to those with cIMT < 0.9 mm (group B). The prevalence of osteoporosis and FRAX BMD, TBS-adjusted FRAX both for M and H were higher in group A compared to group B. The best ROC curves to identify subjects with a cIMT ≥ 0.9 mm were: lumbar spine T-score, with a threshold of − 2.5 SD (area under the curve, AUC 0.64; p = 0.02) with a sensibility of 50% and a specificity of 76%; TBS-adjusted FRAX H with a sensibility of 50% and a specificity of 72% (AUC 0.64; p = 0.01 with a threshold of 3%). Interleukin-6 positively correlated with FRAX BMD H and M.

Conclusions

FRAX without BMD does not identify subclinical carotid atherosclerosis, while lumbar spine T-score and TBS-adjusted FRAX H similarly detected it with higher specificity for T-score.
Physicochemical factors affecting the wettability of copper mine blasting dust
Authors: Jin Longzhe , Liu Jianguo , Guo Jingzhong , Wang Jiaying , Wang Tianyang
Published: February 2021

To investigate the factors affecting the wettability of copper mine blasting dust, the primary blasting dust was collected from an open-pit copper mine and separated into hydrophilic blasting dust (HLBD) and hydrophobic blasting dust (HBBD) using water flotation method. The physicochemical properties of HLBD and HBBD were measured and compared with each other. The properties included particle size distributions (PSDs), micromorphologies, pore structures, mineral components and surface organic carbon functional groups. The results show that particle size and pore structure of the blasting dust are the main factors affecting its wettability. Specifically, particle size of HBBD is smaller than that of HLBD, and their respiratory dust (less than 10 µm) accounts for 61.74 vol% and 53.00 vol%, respectively. The pore structure of HBBD is more developed, and the total pore volume of HBBD is 1.66 times larger than that of HLBD. The identical mineral compositions were detected in HLBD and HBBD by X-rays diffraction (XRD); however, the surface organic hydrophobic component of HBBD is slightly larger than that of HLBD, this may be the reason for the poor wettability of HBBD. This study is significant to understand the effects of physicochemical properties of copper mine blasting dust on its wettability.
Correction to: The development of genome editing tools as powerful techniques with versatile applications in biotechnology and medicine: CRISPR/Cas9, ZnF- and TALE-nucleases, RNA interference and Cre/loxP
Authors: Schulze Sabrina , Lammers Michael
Published: February 2021

We regret the incorrect designation of the site attacking the 3′-phosphotyrosine as 3′-hydroxyl group in the process following the formation of the Holliday junction intermediate to complete Cre/loxP mediated recombination of homologous DNA fragments.
Global rural value chains and the role of natural disasters in their transformation
Authors: Breiling Meinhard
Published: February 2021

Global rural value chains relate to business activities in non-central locations all over the world. They contain almost all global agricultural production, a major part of global tourism, and minor shares of industry and other services than tourism. Their generated value is more dependent on climate and extreme weather events than what is the case with urban value chains. Concepts of disaster vulnerability and disaster resilience to rural value chains are presented and followed by a system view on global rural value according to four income groups of countries. A different meaning of disasters becomes perceivable for each income group. We come up with four cases of successful in some aspects controversial alterations of global rural value chains: palm oil value chain in ASEAN, the sixth industry in Japan, rural tourism in Asia, and winter tourism in Austria and analyze the impacts of natural disasters in case studies. The business disturbances are manifold, complex, and not entirely adverse. The value at risk in a given location widely depends on the susceptibility of people and environment to a natural disaster, the costs to repair, and possibilities to innovate. Along with economic growth, disasters accelerate transformations in rural value chains and the strive to become more global while contracting in their local extensions.
A density functional theory (DFT) study of the doping effect on 4-[2-(2-N, N-dihydroxy amino thiophene) vinyl] benzenamine
Authors: Mveme Côme Damien Désiré , Tchangnwa Nya Fridolin , Ejuh Geh Wilson , Ndjaka Jean Marie Bienvenu
Published: February 2021

In the present work, density functional theory was used at the B3LYP, CAM-B3LYP and B3PW91 levels with the 6–311 +  + G (d, p) basis set, in other to study the structural, optoelectronic, nonlinear optical, piezoelectric and thermodynamic properties of 4-[2-(2-N, N-dihydroxy amino thiophene) vinyl] benzenamine (DATVB) molecule doped with chlorine and fluorine respectively. The results obtained show that doping significantly improves the properties of this material. The materials obtained after doping 4-[2-(2-(5-(bis (chlorooxy) amino) thiophene) vinyl] benzenamine (BCATVB) and 4-[2-(2-(5-(bis (fluorooxy) amino) thiophene) vinyl] benzenamine (BFATVB) are good semiconductors because their gap energy is range between 1 and 1.5 eV which is less than 3 ev. Their first order hyperpolarizabilities ($${\beta }_{mol}$$

β

mol

) are very high compared to para-nitroaniline (p-NA) known as reference molecule for nonlinear optical properties. The obtained results predisposes them as good nonlinear optical materials with applications in photonics, optical signal processing devices, dynamic imaging, data storage and computer devices. The piezoelectric and pyroelectric coefficients of the fluorinated molecule are higher than those of the reference organic molecule polyvinylidene fluoride. This led us to the conclusion that, these molecules can also be used for applications in piezoelectricity.
Exponent determination in a poorly gauged basin system in Nigeria based on flow characteristics investigation and regionalization method
Authors: Fasipe O. A. , Izinyon O. C.
Published: February 2021

In this study, a method for estimating the exponent “n” values of the catchment-area equations of four sub-basins within the poorly gauged Benin-Owena River Basin Development Authority (BORBDA) in Nigeria is presented to enable the estimation of flows at ungauged sites within the basin and the determination of small hydropower (SHP) potential at different locations in each sub-basin and the entire basin. Optimal prediction of streamflow characteristics in poorly gauged basin requires developing a methodology for extrapolation of data from gauged to ungauged sites within the basin. Four sub-catchments of BORBDA, a poorly gauged basin in Nigeria, were investigated using Remote Sensing (RS), Geographic Information System (GIS), statistical techniques, and Natural Resources Conservation Service-Curve Number (NRCS-CN) hydrological model. Discharge values at gauged sites (Qg) were obtained from recorded discharge values collected for 12 months at an established gauging station in each sub-basin. RS and GIS techniques were used to develop classification maps and obtain crucial data like curve number (CN), elevation, Hydrologic Soil Group (HSG), rainfall intensity, slope, area of gauged and ungauged required for evaluating spatial discharge (ungauged) utilizing NRCS-CN model. From the established model for each sub-basin, exponent “n” in the relationship between discharge and catchment area was obtained to be 0.23, 0.41, 0.71, and 0.74. Using the lumped modeling approach, which considers a watershed as a single unit for computation, where watershed parameters and variables were to be averaged produced “n” = 0.52 for BORBDA area, which is within the range of 0.5–0.85 suggested by previous researchers. Obtained BORBDA exponent “n” was validated for use in the entire basin through soil homogeneity test by generating BORBDA soil map which confirms the four sub-basins investigated share similar HSG A, B, and D with BORBDA. The exponent “n” value is useful for predicting flows in ungauged parts of the basin. The exponent “n” value obtained for the basin is helpful in the assessment of discharge and determination of SHP potential at different locations within the poorly gauged BORBDA basin, and the dissemination of the research findings will find practical use and guide to practicing hydrologists in Nigeria and locations around the world with similar challenges of poorly gauged basins particularly Africa and other developing countries.
Stochastic optimization and modeling of high-velocity impact tests on high-temperature carbon–carbon composites
Authors: Aktaş Latif Tibet , Aydın Levent
Published: February 2021

In this study, it is intended to optimize a high-velocity impact case of a composite plate. The case selected from literature focused on the failure response of advanced carbon–carbon (C/C) composites under high-velocity impacts. Based on the stochastic optimization method, three unique models are introduced within the present study's scope as dimensionless damage areas of front and back sides and the composite impact energy response. The difference between the equations found in the present study and the base study is the number of variables. Obtained prediction models consist of only the tests' input variables; thus, these models can be considered the essential prediction functions of high-velocity impact response of C/C composites under high temperatures. Multiple nonlinear regression method is used for objective functions of the optimization problem. Since the determination coefficient values have been found quite similar to the ones in the literature, the presented models can be considered successful in predicting the results. By utilizing the novel regression functions presented in this study, the damaged areas are minimized. Without the necessity of experimental research, further predictions can be made by operating the models found in the present study.
Voltage and frequency control in conventional and PV integrated power systems by a particle swarm optimized Ziegler–Nichols based PID controller
Authors: Ghosh Arabinda , Ray Anjan Kumar , Nurujjaman Md. , Jamshidi Mo
Published: February 2021

Variations of load demands, expansion of power system by interconnections among different areas and integration of renewable energy sources bring new challenges for stable, reliable and uninterrupted operations of power systems. In this paper, a control technique is proposed to control and optimize the performances of the three models having importance in the present and future energy systems. These are the output variations of an automatic voltage regulation (AVR) system, frequency variations in a load frequency control (LFC) system of a thermal power plant and frequency variations of a PV integrated thermal power plant. The proposed controller is a particle swarm optimized Ziegler–Nichols (ZN) method based proportional-integral-derivative (PID) controller. A particle swarm optimization (PSO) method suffers from the unavailability of prior knowledge of initial values of parameters. Whereas, the classical ZN method leaves the scope for performance improvements of a system. A rejuvenation to the classical ZN method is proposed by integrating PSO. The combined effect optimizes the voltage and the frequency performances, while ensuring system stability. Additionally, different objective functions inspired from energy industry requirements are considered to demonstrate performance improvements of the systems (e.g. maximum overshoot, steady-state error, settling time). The robustness of the proposed method is demonstrated by considering parametric uncertainty in the system. The proposed method is compared with performances of different controllers (e.g. PI, fuzzy PI, fuzzy PID), different iterative soft computing methods (e.g. pattern search, artificial bee colony, different variants of PSO) and classical optimization method (e.g. linear matrix inequality) considering different objective functions and different load disturbances for the aforementioned models. It is also observed that better performances are obtained using a significantly less number of iterations.
Time to Work—Opposing Political Rationality with Young Peoples’ Experiences of Working in a Mandatory Activation Context in Norway
Authors: Gjersøe Heidi Moen , Leseth Anne
Published: February 2021

This paper argues that young people, targeted by activation policies, had several temporal experiences with work that can contribute to broadening our understanding of labour market policy for this group of young people. By drawing on qualitative interviews with young people not in employment, education, or training (NEET) in a Norwegian activation context, and by applying anthropological and sociological concepts on temporality and work time in our analysis, we question how time is constructed and reproduced in the establishment of work relations among this group of people. We argue that political discourses of work inclusion for young adults (NEETs) tend to portray work as a means to an end for inclusion. In doing so, they fail to address the complex temporal dimension of work. We find that young adults have a range of complex experiences where disparity between formal and informal aspects of work becomes visible. The temporal dimension of these experiences and the relativity of speed in getting a job are not experienced in a linear manner but as churning between getting a job, having a job, and losing a job.
Morality and Practical Reasons
Authors: Portmore Douglas W.
Published: February 2021

As Socrates famously noted, there is no more important question than how we ought to live. The answer to this question depends on how the reasons that we have for living in various different ways combine and compete. To illustrate, suppose that I've just received a substantial raise. What should I do with the extra money? I have most moral reason to donate it to effective charities but most self-interested reason to spend it on luxuries for myself. So, whether I should live my life as I have most moral reason to live it or as I have most self-interested reason to live it depends on how these and other sorts of reasons combine and compete to determine what I have most reason to do, all things considered. This Element seeks to figure out how different sorts of reasons combine and compete to determine how we ought to live.
The Role of Disgust and Threat in Contamination-Related Obsessive–Compulsive Disorder
Authors: Mulheron Leanne , Jones Mairwen K.
Published: February 2021

Theoretical models suggest that the emotion disgust or threat overestimates are important in the aetiology and maintenance of contamination-based obsessive–compulsive disorder. In the current study, both threat and disgust were manipulated and 115 non-clinical participants (mean age 20.46 years, 94 females) were randomly allocated to one of four conditions: high-disgust/low-threat (n = 29), high-disgust/high-threat (n = 29), low-disgust/low-threat (n = 27), and low-disgust/high-threat (n = 30). Participants completed a hierarchical Behavioural Avoidance Task (BAT). Those in the high-threat and high-disgust conditions completed less BAT steps and showed more latency to begin each step than those in the low-threat and low-disgust conditions. A significant interaction effect was observed for the high-disgust/high-threat condition as significantly more task avoidance was found. However, handwashing duration was not significantly different between the high and low-disgust conditions or the high and low-threat conditions. The overall low mean washing duration of 30 s possibly due to the testing conditions and/or the ethnic heterogeneity of the sample may account for these results. There were also no significant differences in the level of anxiety for participants in the high-threat compared with the low-threat conditions. It is possible that anxiety remained relatively low across conditions as a result of the graduated BAT. Future research and theoretical and clinical implications are discussed.
Strategic non-nuclear weapons and the onset of a Third Nuclear Age
Authors: Futter Andrew , Zala Benjamin
Published: February 2021

Three decades after what is widely referred to as the transition from a First to a Second Nuclear Age, the world stands on the cusp of a possible Third Nuclear Age where the way that we conceptualise the central dynamics of the nuclear game will change again. This paradigm shift is being driven by the growth and spread of non-nuclear technologies with strategic applications and by a shift in thinking about the sources of nuclear threats and how they should be addressed, primarily, but not solely, in the United States. Recent scholarship has rightly identified a new set of challenges posed by the development of strategic non-nuclear weaponry (SNNW). But the full implications of this transformation in policy, technology and thinking for the global nuclear order as a whole have so far been underexplored. To remedy this, we look further ahead to the ways in which current trends, if taken to their logical conclusion, have the capacity to usher in a new nuclear era. We argue that in the years ahead, SNNW will increasingly shape the nuclear order, particularly in relation to questions of stability and risk. In the Third Nuclear Age, nuclear deployments, postures, balances, arms control, non-proliferation policy, and the prospects for disarmament, will all be shaped as much by developments in SNNW capabilities as by nuclear weapons. Consequently, we advocate for an urgent reassessment of the way nuclear order and nuclear risks are conceptualised as we confront the challenges of a Third Nuclear Age.
Influence of Late Holocene climate on Lake Eggers hydrology, McMurdo Sound
Authors: Chamberlain E.J. , Christ A.J. , Fulweiler R.W.
Published: February 2021

Ice-covered lakes in Antarctica preserve records of regional hydroclimate and harbour extreme ecosystems that may serve as terrestrial analogues for exobiotic environments. Here, we examine the impacts of hydroclimate and landscape on the formation history of Lake Eggers, a small ice-sealed lake, located in the coastal polar desert of McMurdo Sound, Antarctica (78°S). Using ground penetrating radar surveys and three lake ice cores we characterize the ice morphology and chemistry. Lake ice geochemistry indicates that Lake Eggers is fed primarily from local snowmelt that accreted onto the lake surface during runoff events. Radiocarbon ages of ice-encased algae suggest basal ice formed at least 735 ± 20 calibrated years before present (1215 C.E.). Persisting through the Late Holocene, Lake Eggers alternated between periods of ice accumulation and sublimation driven by regional climate variability in the western Ross Sea. For example, particulate organic matter displayed varying δ15N ratios with depth, corresponding to sea ice fluctuations in the western Ross Sea during the Late Holocene. These results suggest a strong climatic control on the hydrologic regime shifts shaping ice formation at Lake Eggers.
Effects of Situational Factors on Team Planning
Authors: Oldeweme Martina , Konradt Udo , Garbers Yvonne
Published: February 2021

Abstract. Although there has long been consensus in team research that planning generally has a positive impact on performance, very little is known about how input factors (e. g., situational factors) affect the planning behavior of teams. In addition, the various dimensions of planning remain largely unexplored. In this study, we examine the effects of time pressure, task routine, and decision importance on team planning. We suggest that planning consists of four dimensions: exploration, strategic planning, detailed planning, and prognosis. In two policy-capturing studies, undergraduates and employees were presented with a series of hypothetical scenarios and asked to indicate in each case how they might plan for these if working as part of a team. Results from our Bayesian multilevel analyses revealed that teams overall used less planning when they were under acute time pressure, when tasks were very routine, and when the decisions involved were of little importance.
New Type of Short High‐Frequency VLF Patches (“VLF Birds”) Above 4–5 kHz
Authors: Manninen Jyrki , Kleimenova Natalia , Turunen Tauno , Nikitenko Alexander , Gromova Liudmila , Fedorenko Yury
Published: February 2021

The new type of daytime natural very low frequency (VLF) whistler mode emissions of the magnetospheric origin was found in the VLF observations at Kannuslehto station (L ∼ 5.5) in Northern Finland. The events occurred at the frequencies above 4–5 kHz even up to 15 kHz. These emissions have never been observed earlier in the spectrograms because they were hidden by strong impulsive atmospherics (sferics) in the same frequency range originating in lightning discharges. After filtering out the sferics, we surprisingly discovered completely new types of high frequency right‐hand polarized peculiar VLF emissions with various unusual dynamic spectra. These new VLF emissions typically occur as a sequence of a number of short (∼1–3 min) burst‐like structures or single short patches with the total duration up to a few hours. The spectral peculiarities of several long‐lasting VLF events as well as individual short VLF patches are discussed. The dynamic spectra of these new VLF patches raise the question of the temporal and spatial details of the wave‐particle interactions in the magnetospheric plasma. These emissions are observed only under quiet or weakly disturbed space weather conditions, but during small negative values of the Dst index, indicating the presence of a certain excess of the radiation belt electrons. Note, these high frequency VLF patches are observed at the frequencies much higher than the half of the equatorial electron gyrofrequency which is equal to ∼2.7 kHz at L ∼ 5.5. It seems that these emissions are generated deep in the magnetosphere, but the detailed nature, generation region, and propagation behavior of these newly discovered VLF emissions remain unknown. An appearance of high frequency VLF patches could be an indirect indicator of a local enhancement of electron fluxes in the radiation belt that are not directly measured and may occur even in the absence of visible ground‐based geomagnetic disturbances. Further researches may shed new light on wave‐particle interactions occurring in the Earth's radiation belts.
Comparison of Flexible and Rigid Vegetation Induced Shear Layers in Partly Vegetated Channels
Authors: Caroppi Gerardo , Västilä Kaisa , Gualtieri Paola , Järvelä Juha , Giugni Maurizio , Rowiński Paweł M.
Published: February 2021

Natural riparian vegetation generally presents a complex hydrodynamic behavior governed by plant morphology and flexibility. By contrast, hydrodynamic processes in partly vegetated channels are conventionally simulated by using simplified model vegetation, such as arrays of rigid cylinders. The aim of this study is to investigate the impacts of embedding natural plant features in the experimental simulation of flow in partly vegetated channels. Unique comparative experiments were carried out with both reconfiguring vegetation made of natural‐like shrubs and grasses, and with rigid cylinders. While the lateral distributions of flow properties presented a high similarity governed by the shear layer differential velocity ratio, the bulk vegetative drag, and the presence of large‐scale vortices, the flexibility‐induced mechanisms of natural‐like vegetation markedly affected the flow at the interface. Differences in plant morphology and spacing, and the dynamic motion of flexible foliated plants induced deeper vortex penetration into the vegetation. The normalized shear penetration was 6–10 times greater than observed for rigid cylinders, resulting in wider zones significantly exchanging momentum with the adjacent open water. The efficiency of lateral momentum transport for flexible foliated vegetation was up to 40% greater than the corresponding rigid cylinder case. Overall, the results indicated that improving the representativeness of model vegetation is a critical step toward the accurate simulation of hydrodynamic and transport processes in natural settings.
The molecular conformation of silk fibroin regulates osteogenic cell behavior by modulating the stability of the adsorbed protein-material interface
Authors: Long Yanlin , Cheng Xian , Jansen John A. , Leeuwenburgh Sander G. C. , Mao Jing , Yang Fang , Chen Lili
Published: February 2021

Silk fibroin (SF) can be used to construct various stiff material interfaces to support bone formation. An essential preparatory step is to partially transform SF molecules from random coils to β-sheets to render the material water insoluble. However, the influence of the SF conformation on osteogenic cell behavior at the material interface remains unknown. Herein, three stiff SF substrates were prepared by varying the β-sheet content (high, medium, and low). The substrates had a comparable chemical composition, surface topography, and wettability. When adsorbed fibronectin was used as a model cellular adhesive protein, the stability of the adsorbed protein-material interface, in terms of the surface stability of the SF substrates and the accompanying fibronectin detachment resistance, increased with the increasing β-sheet content of the SF substrates. Furthermore, (i) larger areas of cytoskeleton-associated focal adhesions, (ii) higher orders of cytoskeletal organization and (iii) more elongated cell spreading were observed for bone marrow-derived mesenchymal stromal cells (BMSCs) cultured on SF substrates with high vs. low β-sheet contents, along with enhanced nuclear translocation and activation of YAP/TAZ and RUNX2. Consequently, osteogenic differentiation of BMSCs was stimulated on high β-sheet substrates. These results indicated that the β-sheet content influences osteogenic differentiation of BMSCs on SF materials in vitro by modulating the stability of the adsorbed protein-material interface, which proceeds via protein-focal adhesion-cytoskeleton links and subsequent intracellular mechanotransduction. Our findings emphasize the role of the stability of the adsorbed protein-material interface in cellular mechanotransduction and the perception of stiff SF substrates with different β-sheet contents, which should not be overlooked when engineering stiff biomaterials.