bluuebunny/crossref_metadata_2025 huggingface dataset:
A Logarithmic Bound for Simultaneous Embeddings of Planar Graphs
Authors: Steiner Raphael
Published: June 2024

A set $${\mathcal {G}}$$
G
of planar graphs on the same number n of vertices is called simultaneously embeddable if there exists a set P of n points in the plane such that every graph $$G \in {\mathcal {G}}$$

G
∈
G

admits a (crossing-free) straight-line embedding with vertices placed at points of P. A conflict collection is a set of planar graphs of the same order with no simultaneous embedding. A well-known open problem from 2007 posed by Brass, Cenek, Duncan, Efrat, Erten, Ismailescu, Kobourov, Lubiw and Mitchell, asks whether there exists a conflict collection of size 2. While this remains widely open, we give a short proof that for sufficiently large n there exists a conflict collection consisting of at most $$(3+o(1))\log _2(n)$$

(
3
+
o

(
1
)

)

log
2

(
n
)

planar graphs on n vertices. This constitutes a double-exponential improvement over the previously best known bound of $$O(n\cdot 4^{n/11})$$

O
(
n
·

4

n
/
11

)

for the same problem by Goenka et al. (Graphs Combin 39:100, 2023). Using our method we also provide a computer-free proof that for every integer $$n\in [107,193]$$

n
∈
[
107
,
193
]

there exists a conflict collection of 30 planar n-vertex graphs, improving upon the previously smallest known conflict collection consisting of 49 graphs of order 11, which was found using heavy computer assistance. While the construction by Goenka et al. was explicit, our construction of a conflict collection of size $$O(\log n)$$

O
(
log
n
)

is based on the probabilistic method and is thus only implicit. Motivated by this, for every large enough n we give a different, fully explicit construction of a collection of less than $$n^6$$

n
6

planar n-vertex graphs with no simultaneous embedding.
Can you feel the force just right? Tactile force feedback for training of minimally invasive surgery—evaluation of vibration feedback for adequate force application
Authors: von Bechtolsheim Felix , Bielert Florian , Schmidt Sofia , Buck Nathalie , Bodenstedt Sebastian , Speidel Stefanie , Lüneburg Lisa-Marie , Müller Thomas , Fan Yichen , Bobbe Tina , Oppici Luca , Krzywinski Jens , Dobroschke Jakob , Weitz Jürgen , Distler Marius , Oehme Florian
Published: June 2024

Background

Tissue handling is a crucial skill for surgeons and is challenging to learn. The aim of this study was to develop laparoscopic instruments with different integrated tactile vibration feedback by varying different tactile modalities and assess its effect on tissue handling skills.

Methods

Standard laparoscopic instruments were equipped with a vibration effector, which was controlled by a microcomputer attached to a force sensor platform. One of three different vibration feedbacks (F1: double vibration > 2 N; F2: increasing vibration relative to force; F3: one vibration > 1.5 N and double vibration > 2 N) was applied to the instruments. In this multicenter crossover trial, surgical novices and expert surgeons performed two laparoscopic tasks (Peg transfer, laparoscopic suture, and knot) each with all the three vibration feedback modalities and once without any feedback, in a randomized order. The primary endpoint was force exertion.

Results

A total of 57 subjects (15 surgeons, 42 surgical novices) were included in the trial. In the Peg transfer task, there were no differences between the tactile feedback modalities in terms of force application. However, in subgroup analysis, the use of F2 resulted in a significantly lower mean-force application (p-value = 0.02) among the student group. In the laparoscopic suture and knot task, all participants exerted significantly lower mean and peak forces using F2 (p-value < 0.01). These findings remained significant after subgroup analysis for both, the student and surgeon groups individually. The condition without tactile feedback led to the highest mean and peak force exertion compared to the three other feedback modalities.

Conclusion

Continuous tactile vibration feedback decreases the mean and peak force applied during laparoscopic training tasks. This effect is more pronounced in demanding tasks such as laparoscopic suturing and knot tying and might be more beneficial for students. Laparoscopic tasks without feedback lead to increased force application.
Family adjustment and resilience after a parental cancer diagnosis
Authors: Perak Katarina , McDonald Fiona E. J. , Conti Janet , Yao Yi Sing , Skrabal Ross Xiomara
Published: June 2024

Purpose

To explore the resources, parents with cancer and their partners draw upon to sustain their family resilience through the cancer experience.

Methods

Fifteen participants who were parents of children aged 8 to 25 years completed phone, audio-recorded, and semi-structured interviews. Of these participants, 11 were parents diagnosed with cancer, and four were partners of a parent diagnosed with cancer. Interview questions aimed to increase understanding about how families communicate, connect, and face challenges from the cancer experience. Interview data was analysed using inductive thematic analysis to provide scope to generate themes from parent’s experiences rather than to test pre-existing frameworks.

Results

The thematic analysis of interview transcripts generated three key themes related to family resilience: (1) adaptability to changes in roles and routines, (2) open communication within the family, and (3) accepting support from others.

Conclusion

This study found that parents’ ability to use personal resources when faced with significant challenges helped to improve the resilience of parents’ family system. Further research is needed to understand the factors that influence family resilience when a parent is diagnosed with cancer. Implications for the development of targeted interventions that provide support to not only the patient, but their whole family system will be discussed.
Development of optimal L-PBF process parameters using an accelerated discrete element simulation framework
Authors: Aarab Marwan , Dorussen Bram J. A. , Poelsma Sandra S. , Remmers Joris J. C.
Published: June 2024

Laser Powder Bed Fusion (L-PBF) has immense potential for the production of complex, lightweight, and high-performance components. The traditional optimization of process parameters is costly and time-intensive, due to reliance on experimental approaches. Current numerical analyses often model single-line scans, while it is necessary to model multiple fully scanned layers to optimize for bulk material quality. Here, we introduce a novel approach utilizing discrete element simulations with a ray tracing-modeled laser heat source. Our approach significantly reduces the cost and time consumption compared to conventional optimization methods. GPU acceleration enables efficient simulation of multiple layers, resulting in parameters optimized for bulk material. In a case study, parameters were optimized for AlSi10Mg in just 5 days, a process that would have taken over 8 months without GPU acceleration. Experimental validation affirms the quality of the optimized process parameters, achieving an optical density of 99.91%.

Graphical Abstract

Optimization using the accelerated simulation yielded an optimized parameter set within 5 days. This resulted in a
part with an optical density of 99.91%.
Universal heavy-ball method for nonconvex optimization under Hölder continuous Hessians
Authors: Marumo Naoki , Takeda Akiko
Published: June 2024

We propose a new first-order method for minimizing nonconvex functions with Lipschitz continuous gradients and Hölder continuous Hessians. The proposed algorithm is a heavy-ball method equipped with two particular restart mechanisms. It finds a solution where the gradient norm is less than $$\varepsilon $$
ε
in $$O(H_{\nu }^{\frac{1}{2 + 2 \nu }} \varepsilon ^{- \frac{4 + 3 \nu }{2 + 2 \nu }})$$

O
(

H

ν

1

2
+
2
ν

ε

-

4
+
3
ν

2
+
2
ν

)

function and gradient evaluations, where $$\nu \in [0, 1]$$

ν
∈
[
0
,
1
]

and $$H_{\nu }$$

H
ν

are the Hölder exponent and constant, respectively. This complexity result covers the classical bound of $$O(\varepsilon ^{-2})$$

O
(

ε

-
2

)

for $$\nu = 0$$

ν
=
0

and the state-of-the-art bound of $$O(\varepsilon ^{-7/4})$$

O
(

ε

-
7
/
4

)

for $$\nu = 1$$

ν
=
1

. Our algorithm is $$\nu $$
ν
-independent and thus universal; it automatically achieves the above complexity bound with the optimal $$\nu \in [0, 1]$$

ν
∈
[
0
,
1
]

without knowledge of $$H_{\nu }$$

H
ν

. In addition, the algorithm does not require other problem-dependent parameters as input, including the gradient’s Lipschitz constant or the target accuracy $$\varepsilon $$
ε
. Numerical results illustrate that the proposed method is promising.
Noninvasive pressure-strain loop quantitative assessment of left ventricular function in anemic preterm infants with different modes of respiratory support
Authors: Wang Ruijie , Yang Hui , Jiang Jingbo , Lin Zhou , Zheng Qiuying , Yu Wei , Fan Shumin , Liu Lei
Published: June 2024

To investigate noninvasive pressure-strain loop (PSL) combined with two-dimensional speck tracking imaging and left ventricular pressure measurement in the evaluation of cardiac function changes in anemia of prematurity (AOP) with different modes of respiratory support, and to explore its value in detecting subclinical myocardial injury in preterm infants. This retrospective study included 79 preterm infants with anemia, according to different modes of respiratory support, who were divided into invasive respiratory support group (39 cases) and noninvasive respiratory support group (40 cases). A control group of 40 nonanemic preterm infants with matched age, sex, and gestational age were also included. Complete echocardiography was performed for each included infant. There are PSL parameters that used to evaluate cardiac function, including global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) among the three groups were compared. Compared with the control group, the value of GWI, GCW, and GWE were significantly lower and GWW was higher in the AOP groups (P < 0.05), and GWI, GCW and GWE were much significantly lower in the invasive respiratory support group than in the noninvasive respiratory support group (P < 0.05). There was no significant difference in GLS among the three groups (P > 0.05). Noninvasive PSL analysis can quantitatively assess myocardial work in AOP with different respiratory support, which is more sensitive than other conventional echocardiographic indices. This technique may provide a new method for monitoring subclinical myocardial injury with AOP.
Modeling the impact of out-of-schema questions in task-oriented dialog systems
Authors: Meem Jannat Ara , Rashid Muhammad Shihab , Hristidis Vagelis
Published: June 2024

Existing work on task-oriented dialog systems generally assumes that the interaction of users with the system is restricted to the information stored in a closed data schema. However, in practice users may ask ‘out-of-schema’ questions, that is, questions that the system cannot answer, because the information does not exist in the schema. Failure to answer these questions may lead the users to drop out of the chat before reaching the success state (e.g. reserving a restaurant). A key challenge is that the number of these questions may be too high for a domain expert to answer them all. We formulate the problem of out-of-schema question detection and selection that identifies the most critical out-of-schema questions to answer, in order to maximize the expected success rate of the system. We propose a two-stage pipeline to solve the problem. In the first stage, we propose a novel in-context learning (ICL) approach to detect out-of-schema questions. In the second stage, we propose two algorithms for out-of-schema question selection (OQS): a naive approach that chooses a question based on its frequency in the dropped-out conversations, and a probabilistic approach that represents each conversation as a Markov chain and a question is picked based on its overall benefit. We propose and publish two new datasets for the problem, as existing datasets do not contain out-of-schema questions or user drop-outs. Our quantitative and simulation-based experimental analyses on these datasets measure how our methods can effectively identify out-of-schema questions and positively impact the success rate of the system.
Improving risk governance strategies via learning: a comparative analysis of solar radiation modification and gene drives
Authors: Grieger Khara , Wiener Jonathan B. , Kuzma Jennifer
Published: June 2024

Stratospheric aerosol injection (SAI) and gene drive organisms (GDOs) have been proposed as technological responses to complex entrenched environmental challenges. They also share several characteristics of emerging risks, including extensive uncertainties, systemic interdependencies, and risk profiles intertwined with societal contexts. This Perspective conducts a comparative analysis of the two technologies, and identifies ways in which their research and policy communities may learn from each other to inform future risk governance strategies. We find that SAI and GDOs share common features of aiming to improve or restore a public good, are characterized by numerous potential ecological, societal, and ethical risks associated with deep uncertainty, and are challenged by how best to coordinate behavior of different actors. Meanwhile, SAI and GDOs differ in their temporal and spatial mode of deployment, spread, degree and type of reversibility, and potential for environmental monitoring. Based on this analysis, we find the field of SAI may learn from GDOs by enhancing its international collaborations for governance and oversight, while the field of GDOs may learn from SAI by investing in research focused on economics and decision-modeling. Additionally, given the relatively early development stages of SAI and GDOs, there may be ample opportunities to learn from risk governance efforts of other emerging technologies, including the need for improved monitoring and incorporating aspects of responsible innovation in research and any deployment.
A mechanistic approach to determine the relationship between film structure, electronic properties, and photocatalytic activity of ALD ZnO thin films on glass gibers
Authors: Arat Asife B. , Akyildiz Halil I.
Published: June 2024

Atomic layer deposition (ALD), a high-conformality thin-film deposition technique, offers the opportunity to immobilize photocatalytic materials on high surface area substrates. Textile substrates are inexpensive, easily accessible materials with a fibrous nature, making them high surface area scaffolds for photocatalytic applications. This study applied ZnO thin-film coatings to fabric structures with different numbers of ALD cycles. The effect of coating thickness on the surface and electronic properties of the films and their photocatalytic properties were investigated. SEM, XRD, PL, and UV–Vis were used to examine the surface morphology, crystal structure, defects, and optical properties of the ZnO thin films. As the film thickness increased, the crystal sizes and the number of defects in the structure increased. Contact angle and Hall Effect measurements revealed that these structural defects are present on the surface of the films. Optimum wettability, mobility, and photocatalytic efficiency values were observed in the 15-nm coated samples, resulting in the highest photocatalytic activity and a turning point.
Cosolvent-free sol–gel synthesis of macroporous silica gels from tetramethoxysilane–tetraethoxysilane mixtures
Authors: Koreeda Hiroka , Ishijima Masanao , Kajihara Koichi
Published: June 2024

Tetramethoxysilane (TMOS), tetraethoxysilane (TEOS), and their mixtures were used for the cosolvent-free synthesis of macroporous silica gels as precursors for monolithic silica glasses. The liquid-state 29Si nuclear magnetic resonance (NMR) spectroscopy of precursor solutions indicated that cross-transesterification between TMOS and TEOS was completed in a few hours at 20 °C in the presence of an acid catalyst, whereas it was negligible when the catalyst was absent. In the precursor solutions prepared from TMOS, phase separation occurred after gelation, resulting in translucent gels. In contrast, in the solutions prepared from TEOS or a mixture of TMOS and TEOS at a TMOS mole fraction of 0.8, the phase separation can be induced before gelation, and opaque xerogels were easily obtained without fracture. The average size of macroscopic particles and macroporous structures were uniform over opaque xerogels prepared from TEOS. In contrast, in opaque xerogels prepared from the TMOS-rich mixture of TMOS and TEOS, the average particle size and macroscopic porosity inside them were notably smaller than those of the subsurface, probably because of a large exotherm upon gelation and the resulting temperature gradient in the gelling solutions. Such spatial morphology distribution made the sintering of the opaque gels into clear silica glasses difficult. Opaque gels prepared from TEOS and translucent gels prepared from solutions containing TMOS were transformed to clear silica glasses in high yields of ~99% by sintering in a helium atmosphere at 1050–1350 °C.

Graphical abstract
Structural, Mechanical and Tribological Properties of Hydroxiapatite Reinforced Ti13Nb13Zr/HA Composite Produced by Friction Stir Process (FSP)
Authors: ACIMERT Özlem Baran , Okur Beyza Begüm , Dayauç Ayşenur Keleş , Küçükömeroğlu Tevfik , Kanca Yusuf
Published: June 2024

Many modification methods are applied to produce Ti-based biomedical materials. In this study, the structural, mechanical and tribological properties of unreinforced Ti13Nb13Zr alloy and Ti13Nb13Zr/HA composites with different contents of hydroxyapatite (HA) reinforcement were investigated by friction stir processing (FSP) to Ti13Nb13Zr alloy. SEM, FTIR and EDS analyzes were performed to determine the structural properties. Surface roughness values were determined using a 3D optical microscope. Surface wettability properties were investigated with a contact angle. Microhardness and wear test devices were used to determine the mechanical and tribological properties, respectively. Wear tests were carried out in a dry environment and phosphate buffered saline solution (PBS). The wear tracks were analyzed by SEM and 3D optical microscope. As a result of FTIR analysis, HA has PO43−, HPO42−, CO32− and OH− bonds. All samples exhibited hydrophilic surfaces suitable for cell adhesion. The FSP process increased the hardness and wear resistance of the Ti13Nb13Zr alloy in both atmospheres. In addition, Ti13Nb13Zr/HA composites significantly increased the hardness and wear resistance of Ti13Nb13Zr alloy and Ti13Nb13Zr alloy modified by FSP.
Wasch mich, aber mach mich nicht nass?
Authors: Scherr Albert
Published: June 2024

Ob die Berufsausübung an eine staatliche Anerkennung gebunden sein soll, wird in der Sozialen Arbeit kontrovers diskutiert. Im vorliegenden Beitrag wird in einer professionstheoretischen Perspektive aufgezeigt, dass die einschlägige Debatte einerseits auf Defizite in der Gewährleistung professioneller Standards verweist, die auch durch unzureichende berufsständische Selbstkontrolle bedingt sind. Andererseits steht sie in Zusammenhang mit der Zuweisung hoheitsstaatlicher Aufgaben an die Soziale Arbeit und dem daraus resultierenden Interesse an staatlicher Kontrolle derjenigen, die mit deren Durchsetzung befasst sind. Argumentiert wird, dass das bloße Vertrauen in durch hochschulische Ausbildung individueller Kompetenzen und Selbstverpflichtungen von Sozialarbeitenden keine überzeugende Alternative zur entweder staatlichen oder berufsständischen Regulierung der Berufsausübung ist.
Magnum metal-on-metal uncemented total hip replacement: 8- to 18-year outcomes of 211 cases
Authors: Gaillard-Campbell D. , Gross T.
Published: June 2024

Background

Reports of adverse reactions to metal debris contributed in part to a decline in use of large-bearing metal-on-metal total hip devices. We hypothesize an optimal trunnion design may reduce risk of this failure mode in large-bearing total hip arthroplasty systems. The purpose of this study is to report mid- to long-term outcomes for a single-surgeon series of 211 total hip arthroplasties using the large-bearing Biomet Magnum metal-on-metal system.

Materials and methods

Between December 2004 and January 2016, the primary surgeon performed 211 uncemented Magnum total hip arthroplasties in 181 patients. The average length of follow-up was 10.1 ± 3.5 years (range 8–18 years).

Results

Using failure of any component as the endpoint, the overall survivorship rate was 98.1% at 10 years and 97.4% at 18 years. These eight failures (3.8% of cohort) included one case of adverse wear-related failure (0.5%), two cases of acetabular ingrowth failure (0.9%), three cases of trunnion corrosion (1.4%), one failure of late infection (0.5%), and one inappropriate revision of components for trochanteric nonunion without instability (0.5%). Excluding failed cases, all components were radiographically stable with no radiolucencies. Except for the one wear failure, ion testing revealed that 97.2% of cases were within optimal whole blood metal ion levels with the remaining ion test results within acceptable levels.

Conclusions

With the uncemented Magnum metal-on-metal total hip, we achieved 97.4% 18-year implant survivorship, exceeding the NICE criteria and registry benchmarks for implant survivorship. We observed a trunnion corrosion rate of 1.4% and no cases of instability. The single case of adverse wear-related failure was caused by acetabular component malposition.
Investigating the vaporization mechanism's effect on interfacial tension during gas injection into an oil reservoir
Authors: Mehrjoo Hossein , Safaei Ali , Kazemzadeh Yousef , Riazi Masoud , Hasan-zadeh Atefe
Published: June 2024

In gas injection, which is one of the fascinating enhanced oil recovery techniques, the main mechanism involves decreasing interfacial tension (IFT). Although various mechanisms can affect the IFT of a system, in most experimental and numerical studies, condensation is considered the dominant mechanism among condensation-vaporization and vaporization. Investigating the impact of each mechanism is crucial as they can influence the IFT of the system and, consequently, the effectiveness of the gas injection method. This study introduces a novel model to assess the influence of different mechanisms on system IFT. The model defines system IFT, adjusts fluid relative permeability to represent miscible, immiscible, and near-miscible states, and utilizes the Buckley–Leverett method to analyze gas fractional flow and saturation profiles when injecting carbon dioxide (CO2), methane (CH4), and nitrogen (N2). Furthermore, the research explores the impact of injection pressure and IFT at minimum miscible pressure (IFT0) on gas injection efficiency. Based on our results, for both live and dead oil, the condensation mechanism reduces IFT and near-miscible pressure; switching to a condensing-vaporizing mechanism increases these parameters. This trend was consistent across all gases studied (N2, CO2, CH4), with a more significant effect observed on the CH4-live oil system compared to N2 and CO2. Controlling the condensing mechanism in IFT measurements enhances gas flow rate and relative permeability curve within the medium. Higher injection pressure in the condensing mechanism and IFT0 = 0.5 leads to faster fluid movement and improved relative permeability due to increased driving forces. Higher IFT0 accelerates the relative permeability of fluids and gas movement within the medium by promoting miscibility sooner. The impact of IFT0 was more pronounced on the dead oil–gas system compared to the live oil–gas system in this study.
The Use of Indigenous Knowledge Systems Practices to Enhance Food Security in Vhembe District, South Africa
Authors: Kom Zongho , Nicolau Melanie D. , Nenwiini Shandukani C.
Published: June 2024

This paper seeks to examine how subsistence farmers employ indigenous knowledge methods to enhance food security within rural communities in the Vhembe district. It analyses indigenous knowledge practices used in managing climate change impacts on crop production and determines indigenous knowledge processes used to preserve food to fill the gap during food shortages. The paper also considers the indigenous weather prediction approaches used in the area. A participatory rural appraisal is complemented by a qualitative and quantitative approach. This study used semi-structured interviews, questionnaires and focus group discussions for data collection. A survey of 200 randomly selected indigenous farmers was sampled. The finding revealed that local farmers depend on the use of indigenous knowledge practices to improve household food security. The majority of farmers apply manure in their farms using livestock dumps. Also, it shows that 87.8% of households used sun-drying processes for food preservation and used local mortars to pound and grind foodstuffs such as peanuts and maize. Practices such as crop rotations, mixed cropping and intercropping were employed to improve soil fertility and climate change and reduce insect pest outbursts on crops, hence, improving crop production. Indigenous knowledge of rainfall prediction is helpful in preparation for the planting season. The study recommended that agriculture policies must acknowledge indigenous knowledge practices in development programmes and specific policy interventions to promote the indigenous knowledge systems must focus on enhancing socio-economic factors assisting farmers in improving post-harvest storage facilities. The findings could facilitate interaction between indigenous knowledge stakeholders and the Limpopo provincial agriculture training institution. The fulfilment of the United Nations Sustainable Development Goal 2 on zero hunger and food security could benefit from the indigenous knowledge systems.
On the sensitivity of DEM parameters on pile experiments
Authors: Jahn Momme , Meywerk Martin
Published: June 2024

The discrete element method (DEM) is suitable to investigate problems where large deformations occur especially in granular material. The fitting of reliable DEM parameters is crucial and a challenge which is caused by the high number of DEM parameters and the computational effort. Despite its drawbacks, a trial and error approach is often used for the DEM parameter calibration. The knowledge of the DEM parameter influence on the model response is necessary to improve the calibration and to check whether the experiment is suitable to calibrate specific parameters or not. It is possible to reduce the dimensionality of the optimisation problem by omitting parameters whose influence on the model response is negligibly small. One approach is to perform a global sensitivity analysis based on Sobol’ indices. A frequently used calibration experiment in literature is the pile experiment. The deviation between the experiment and the simulation is evaluated with the angle of repose. In the present paper, an algorithm to determine the angle of repose considering the three-dimensional shape of the heap is discussed. The global sensitivity analysis is performed for two different experimental heap set-ups. To decrease the computational effort of the sensitivity analysis, the model response is approximated with metamodels whose predictability is evaluated using the root mean squared error (RMSE) based on a separate sampling point set.
Virtuelle Führung in Krisenzeiten
Authors: Efimov Ilona , Harth Volker , Mache Stefanie
Published: June 2024

Hintergrund und Zielstellung

Die COVID-19-Pandemie führte zu erheblichen Veränderungen an Büroarbeitsplätzen. Bislang bestehen nur wenige Studien zu den Auswirkungen der pandemiebedingten Einführung von digitaler, remote Zusammenarbeit auf Führungskräfte. Das Ziel dieser Studie ist es, zu untersuchen, welche Veränderungen und welche Unterstützung Führungskräfte während der COVID-19-Pandemie erlebt haben.

Methoden

In dieser qualitativen Interviewstudie wurden 16 Führungskräfte mittels halbstrukturierter, leitfadengestützter Telefoninterviews von Mai bis Juli 2021 zu ihren Erfahrungen während der COVID-19-Pandemie befragt. Die erhobenen Daten wurden transkribiert, anonymisiert und induktiv anhand der Qualitativen Inhaltsanalyse nach Mayring ausgewertet.

Ergebnisse

Die Führungskräfte berichteten zum einen von arbeitsorganisatorischen Veränderungen ihrer individuellen Arbeitsbedingungen und erhöhten Führungsanforderungen. Zum anderen beschrieben sie sowohl negative als auch positive Veränderungen in der inhaltlichen Zusammenarbeit, wie z. B. Herausforderungen in der digitalen Kommunikation, der Einarbeitung neuer Teammitglieder, aber auch eine Verbesserung der sozialen Beziehungen im Team. Unterstützung erlebten die Führungskräfte durch z. B. flexible Arbeitsbedingungen, Bereitstellung struktureller Angebote, adäquate technische Ausstattung, Unterstützung durch die Unternehmensleitung oder Kolleg:innen.

Diskussion

In Anbetracht der Relevanz von Führungskräften in Transformationsprozessen und den an sie gestellten hohen Arbeits- und Führungsanforderungen ist die Sicherstellung bedarfsorientierter Unterstützung von Seiten der Organisation von besonderer Bedeutung. Um den Herausforderungen in Krisenzeiten wie der COVID-19-Pandemie begegnen zu können, sollten Organisationen ihren Führungskräften verhaltens- und verhältnispräventive Maßnahmen anbieten.
A GAN based PID controller for highly adaptive control of a pneumatic-artificial-muscle driven antagonistic joint
Authors: Zhou Zhongchao , Lu Yuxi , Kokubu Shota , Tortós Pablo Enrique , Yu Wenwei
Published: June 2024

Upper limb prostheses are commonly propelled by pneumatic artificial muscles organized in an antagonistic arrangement. Nonetheless, the control of upper limb prostheses under changing/unknown situations is difficult and necessary for a variety of real-world applications. Adaptive control, learning-based control, and robust control have been studied to deal with such challenges. However, their adaptability is insufficient for prostheses used in daily life, which are exposed to variable task levels, user motor characteristics, and prosthetic features. This paper introduces a highly adaptive controller for the first time based on Generative Adversarial Nets and proportional–integral–derivative controller (G-PID controller). G-PID controller comprises a generator for generating compensation actions to enhance PID responsiveness when controlling the unknown/changing system. Moreover, it incorporates a discriminator that receives responses from both a user-preselected reference system and the compensated changing/unknown system, and simultaneously determines the source of these responses. Through continuous updates, the compensator modifies the response of unknown/changing system to align with the reference system, thereby facilitating adaptive control. The G-PID controller’s effectiveness is evaluated through 1-degree of freedom (DoF) joint and 2-DoF shoulder prostheses in simulation experiments, and further validated in prototype experiments focusing on online learning for unknown and time-varying payload. The results demonstrate its ability to deal with diverse types of unknowns/changes, marking a significant advancement towards incorporating prostheses seamlessly into daily life.
Geocells for Unpaved Roads: Analysis of Design Methods from the Literature
Authors: Martins Catarina , Macedo Joaquim , Pinho-Lopes Margarida
Published: June 2024

Most forest roads are unpaved, connecting rural and forest areas and enabling access for firefighting and commercial purposes. Low traffic levels lead to reduced functional demands, while rapid development of deformations results in frequent maintenance. Using geocells as reinforcements reduces deformations, minimizing maintenance needs. Herein, geocell-reinforced soil design methods were collected and categorized based on their result: increase in confining pressure; bearing capacity; height of the base layer. The goal was to compare methods reported in the literature, from a user perspective and within each category, using a base scenario. The methods were analysed to better understand their differences and application conditions. Methods that estimate the increase in confining pressure refer to static or cyclic loading, leading to results that are not directly comparable; often, the reinforcement contribution is represented by an apparent cohesion, with no physical meaning and misleading. Methods that estimate the increase in bearing capacity due to geocell consider its contribution differently (lateral resistance, vertical stress dispersion, and membrane effects) and distinct combinations. For geocell reinforcement, the membrane effect can be neglected. Methods that estimate the height of the base layer can be used directly for an expedite design of unpaved roads. When geocell reinforcement is adopted, the minimum height of the base layer should coincide with that of the geocell. Thus, while current methods contribute and support the design of unpaved roads, further work is essential to develop methods that are of simple and of expedite application for forest engineers, adaptable to local conditions and requirements.
Ethnic Minority Inclusion in Well-Being Research: Beyond Widening Participation
Authors: Esmene Shukru , Leyshon Michael , Leyshon Catherine
Published: June 2024

This commentary paper welcomes calls for widening participation amongst ethnic minorities in research that aims to understand well-being. However, we demonstrate how a history of exclusion in the daily routines of communities render such calls limited in their ability to address inclusion fully. The absence of ethnic minorities from spaces and dialogues that define what constitutes good well-being is highlighted. We use life-courses that align with Western norms as an example to develop our arguments. Overall, exclusion is rooted in colonial histories and the discrimination experienced by ethnic minorities during day-to-day, routine living. Additionally, relational ontologies of well-being are overwhelmed by individualised constructs. We outline how the suppression of marginalised values in everyday spaces and activities has limited meaning-making in relation to well-being amongst ethnic minority individuals and groups. We characterise this marginalisation as an epistemic injustice in defining well-being. In our conclusions, we call for dialogues and developments in critical race theory (CRT) to be considered in research commissioning processes. Spaces and dialogues that are owned and shaped by ethnic minorities should be supported before we can widen participation in well-being research meaningfully. Values that are practised and developed in such spaces can then contribute to how communities define well-being and the appropriate ways in which it can be studied. It should be acknowledged that we use the term ethnic minority throughout this paper for brevity. The diverse experiences and perspectives that this term covers should be engaged with when considering the recommendations that we make.
Modeling MobilityCoins—Charges, Incentives and Multi-period Budgets in Multimodal Transportation Networks
Authors: Loder Allister , Bogenberger Klaus
Published: June 2024

MobilityCoins are a tradable mobility credit (TMC) scheme variant. TMC schemes are a cap-and-trade scheme for managing mobility that are designed to limit negative externalities, e.g., congestion, of traffic. Next to having link-specific or origin–destination-specific charges for cars as in the common TMC scheme, the MobilityCoin scheme’s distinctive elements are accommodating link-specific and origin-and-destination-specific charges and incentives for all modes of transport as well as being considered a mobility currency that can be earned, saved, and spent in multiple time periods. These distinctive features of the MobilityCoin scheme does not alter the core behavioral mechanism of TMC schemes of increasing car travel costs, but these features interfere with the credit market in terms of market volume and market price that ultimately affects traffic outcomes, e.g., an uncontrolled market volume increase can lower the market price that in turns increases the attractiveness of using the car. In this paper, we develop a mathematical model of multimodal macroscopic network flows and a MobilityCoin market to investigate the impacts of charges, incentives, and multi-period budgets. The model is implemented as a single-day model with an integration of sensitivity for multi-period budgets to study how the outcomes in the transportation system change with charges, incentives, and multi-period budgets. Further, we discuss implications for the policy design of MobilityCoins schemes.
Professionals’ Fidelity-Adaptation Attitudes: Relation to Implementation Determinants and Work-Life Consequences – A Cluster Analysis
Authors: Zetterlund Johanna , Hasson Henna , Neher Margit , von Thiele Schwarz Ulrica
Published: June 2024

Evidence-based interventions have the potential to improve health and well-being, but their effectiveness depends, among other things, on the challenging act of balancing between fidelity and adaptation, referred to as the fidelity-adaptation dilemma. After initial implementation, it is primarily professionals delivering evidence-based interventions to end users that face the dilemma, but research about how professionals relate to and perceive it is limited. This study aims to describe professionals’ attitudes towards the dilemma and investigate the associations between professional attitudes and individual and organisational implementation determinants, individual characteristics, and work-life consequences for the professionals. Using a cross-sectional design, 103 professionals working with an evidence-based parental support programme ABC (All Children in Focus) were surveyed on attitudes towards the fidelity-adaptation dilemma, implementation determinants, and work-life consequences. Data were analysed using two-step cluster analysis. Three profile groups summarize professionals’ attitudes: one preferring fidelity (the adherers, n = 31), one preferring adaptations (the adapters, n = 50), and one with a dual view on fidelity and adaptation (the double-minded, n = 18). The adherers, the ones preferring fidelity, reported higher levels of skills, knowledge, openness, work-related self-efficacy, meaning of work, and possibilities for development, and a lower level of role conflict and unreasonable tasks compared to the adapters. Professionals with a positive attitude towards fidelity reports experiencing more job resources and a lower level of job demands compared to professionals who are more positive towards adaptation. The study shows that the fidelity-adaptation dilemma is at play during the sustainment phase of implementation and suggest that it has consequences for professionals working life.
Screening and evaluation of antibacterial active strains of Actinomycetes isolated from Northern Indian soil for biofilm inhibition against selected ESKAPE pathogens
Authors: Dar Muzammil Sharief , Ahmad Iqbal
Published: June 2024

The growing problem of antimicrobial resistance (AMR) globally has warranted the search for new and alternate anti-infective strategies. This study aimed to isolate and screen soil Actinomycetes from three different locations in Northern India for their broad-spectrum antibacterial and antibiofilm activity against certain drug-resistant bacteria from ESKAPE group. A total of 110 isolates of Actinomycetes were screened for antibacterial activity using overlay and agar-well diffusion assay against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Ninety-five isolates showed antibacterial activity against one or more test bacteria. These isolates were tentatively identified as members of genus Streptomyces. Five isolates (IMA13, IMA25, IMA43, IMA46, and IMA47) demonstrated broad-spectrum activity against test pathogens and were subjected to production of secondary metabolites in liquid medium. Ethyl acetate fraction of culture filtrate showed MIC in the range of 64–512 µg/ml against test bacteria. The most active isolate, IMA-46, was identified by 16srRNA gene sequence analysis as Streptomyces rameus. Further, ethyl acetate fraction from S. rameus-IMA46 was used to inhibit biofilm formation at sub-MIC values. A significant level (50% to 92%) of biofilm inhibition was recorded against test pathogens. Light microscopy and SEM analysis revealed the biofilm structural changes, reduction in cell aggregation and EPS production. LC/MS analysis of the active extract of S. rameus IMA46 showed the presence of many biologically active compounds, including tetracycline and doxycycline. The present study highlights the potential of soil Actinomycetes in production of broad-spectrum anti-infective compounds in combating growing problem of AMR.
Spectrophotometric determination of cobalt ions in water using bimetallic chemosensor based on sulfa drug azo dye
Authors: Nassar Sulafa , Mohammed Gharam I.
Published: June 2024

A spectrophotometric technique has been developed for detection of cobalt(II) ions in aqueous solution samples utilising a new chemosensor. This technique relies on the formation of a stable yellow-orange complex at pH = 13 using 4-(2-Hydroxy-naphthalen-1-ylazo)-N-thiazol-2-yl-benzenesulfonamide (H2L) as ligand through complexation with Co(II) ions. At λ = 390 nm, complex absorption was detected. A correlation coefficient of 0.9934 indicated linearity in the concentration range of (1.7–8.4 × 10–5 mol L−1). The limit of detection (LOD) and limit of quantification (LOQ) were assigned to be 0.147 µg ml−1 (2.5 µmol L−1) and 0.489 µg ml−1 (8.3 µmol L−1),respectively. The stoichiometric composition of the complex, which is 2:1 of M:L, was confirmed by the correlation between the continuous variation results and the molar-ratio methods proposed by Job. Additionally, the structure of the solid complex that is produced when H2L reacts with Co(NO3)2.6H2O has been determined by applying different spectroscopic and analytical techniques, confirming the formation of the complex in the same molar ratio as that determined by Job’s method. The geometrical structure of the complex was confirmed to be tetrahedral by a combination of magnetic moment results and UV-Vis spectra.
Advancing diagnostics and disease modeling: current concepts in biofabrication of soft microfluidic systems
Authors: Casanova César R. , Casanova Marta R. , Reis Rui L. , Oliveira Joaquim M.
Published: June 2024

Soft microfluidic systems play a pivotal role in personalized medicine, particularly in in vitro diagnostics tools and disease modeling. These systems offer unprecedented precision and versatility, enabling the creation of intricate three-dimensional (3D) tissue models that can closely emulate both physiological and pathophysiological conditions. By leveraging innovative biomaterials and bioinks, soft microfluidic systems can circumvent the current limitations involving the use of polydimethylsiloxane (PDMS), thus facilitating the development of customizable systems capable of sustaining the functions of encapsulated cells and mimicking complex biological microenvironments. The integration of lab-on-a-chip technologies with soft nanodevices further enhances disease models, paving the way for tailored therapeutic strategies. The current research concepts underscore the transformative potential of soft microfluidic systems, exemplified by recent breakthroughs in soft lithography and 3D (bio)printing. Novel applications, such as multi-layered tissues-on-chips and skin-on-a-chip devices, demonstrate significant advancements in disease modeling and personalized medicine. However, further exploration is warranted to address challenges in replicating intricate tissue structures while ensuring scalability and reproducibility. This exploration promises to drive innovation in biomedical research and healthcare, thus offering new insights and solutions to complex medical challenges and unmet needs.
Preliminary findings from the longitudinal study of big picture learning Australia university pathway students
Authors: Fischetti John , Hill Ann , Lynch Debra , Pettit Joanne , Rutkowski Joanne , White Viv , Chadwick Deborah , Down Barry
Published: June 2024

Year 12 students in Big Picture Learning schools across Australia now use portfolios and interviews to apply for and gain entry to their first choice of university degree. They receive admission on the strength of portfolio evidence mapped to a new non-ATAR qualification, known as the International Big Picture Learning Credential (IBPLC). Since 2020, 270 graduates have received offers to university using the Credential, growing from 3 in 2017. Like other Big Picture graduates who went before them, they are continuing a trajectory of passion-based learning that began in Year 9 or 10 at one of 45 Australian Big Picture Learning schools. All IBPLC graduates begin tertiary study equipped with experiences in the real world, support systems with a range of community mentors and teachers, specialist knowledge in their chosen field, and a set of independent learning skills intended to give them the opportunity to thrive in the university setting. In this article we share the preliminary findings of a study of graduates of Big Picture Learning Australia secondary schools who have matriculated using the IBPLC. Findings from our surveys and interviews show promise that the learning design of Big Picture, which starts with an internship in a passion area, is the key factor in enabling the success of graduates both from high school and into their university studies.
A critical transition of two-dimensional flow in toroidal geometry
Authors: Agoua Wesley , Favier Benjamin , Morales Jorge , Bos Wouter J.T.
Published: June 2024

We investigate two-dimensional (2-D) axisymmetric flow in toroidal geometry, with a focus on a transition between 2-D three-component flow and 2-D two-component flow. This latter flow state allows a self-organization of the system to a quiescent dynamics, characterized by long-living coherent structures. When these large-scale structures orient in the azimuthal direction, the radial transport is reduced. Such a transition, if it can be triggered in toroidally confined fusion plasmas, is beneficial for the generation of zonal flows and should consequently result in a flow field beneficial for confinement.
The influence of President Trump’s micro-expressions during his COVID-19 national address on viewers’ emotional response
Authors: Stewart Patrick A. , Svetieva Elena , Mullins Jeffrey K.
Published: June 2024

This preregistered study replicates and extends studies concerning emotional response to wartime rally speeches and applies it to U.S. President Donald Trump’s first national address regarding the COVID-19 pandemic on March 11, 2020. We experimentally test the effect of a micro-expression (ME) by Trump associated with appraised threat on change in participant self-reported distress, sadness, anger, affinity, and reassurance while controlling for followership. We find that polarization is perpetuated in emotional response to the address which focused on portraying the COVID-19 threat as being of Chinese provenance. We also find a significant, albeit slight, effect by Trump’s ME on self-reported sadness, suggesting that this facial behavior served did not diminish his speech, instead serving as a form of nonverbal punctuation. Further exploration of participant response using the Linguistic Inventory and Word Count software reinforces and extends these findings.
COMPUTING CENTRALISERS IN [FINITELY GENERATED FREE]-BY-CYCLIC GROUPS
Authors: CARVALHO ANDRÉ
Published: June 2024

We prove that centralisers of elements in [finitely generated free]-by-cyclic groups are computable. As a corollary, given two conjugate elements in a [finitely generated free]-by-cyclic group, the set of conjugators can be computed and the conjugacy problem with context-free constraints is decidable. We pose several problems arising naturally from this work.