bluuebunny/crossref_metadata_2025 huggingface dataset:
A systematic review of carbohydrate-based microneedles: current status and future prospects
Authors: Bhadale Rupali S. , Londhe Vaishali Y.
Published: July 2021

Microneedles (MNs) are minimally invasive tridimensional biomedical devices that bypass the skin barrier resulting in systemic and localized pharmacological effects. Historically, biomaterials such as carbohydrates, due to their physicochemical properties, have been used widely to fabricate MNs. Owing to their broad spectrum of functional groups, carbohydrates permit designing and engineering with tunable properties and functionalities. This has led the carbohydrate-based microarrays possessing the great potential to take a futuristic step in detecting, drug delivery, and retorting to biologicals. In this review, the crucial and extensive summary of carbohydrates such as hyaluronic acid, chitin, chitosan, chondroitin sulfate, cellulose, and starch has been discussed systematically, using PRISMA guidelines. It also discusses different approaches for drug delivery and the mechanical properties of biomaterial-based MNs, till date, progress has been achieved in clinical translation of carbohydrate-based MNs, and regulatory requirements for their commercialization. In conclusion, it describes a brief perspective on the future prospects of carbohydrate-based MNs referred to as the new class of topical drug delivery systems.
Correction to: Extendingmultidimensional Poverty Identification: from Additive Weights to Minimal Bundles
Authors: Jones Sam
Published: July 2021

A Correction to this paper has been published: https://doi.org/10.1007/s10888-021-09503-9
The large N limit of orbifold vertex operator algebras
Authors: Gemünden Thomas , Keller Christoph A.
Published: July 2021

We investigate the large N limit of permutation orbifolds of vertex operator algebras. To this end, we introduce the notion of nested oligomorphic permutation orbifolds and discuss under which conditions their fixed point VOAs converge. We show that if this limit exists, then it has the structure of a vertex algebra. Finally, we give an example based on $$\mathrm {GL}(N,q)$$

GL
(
N
,
q
)

for which the fixed point VOA limit is also the limit of the full permutation orbifold VOA.
Existence of quasi-periodic responses in quasi-periodically forced nonlinear mechanical systems
Authors: Breunung Thomas
Published: July 2021

Forced responses of mechanical systems are crucial design and performance criteria. Hence, their robust and reliable calculation is of vital importance. While numerical computation of periodic responses benefits from an extensive mathematical basis, the literature for quasi-periodically forced systems is limited. More specifically, the absence of applicable and general existence criterion for quasi-periodic orbits of nonlinear mechanical systems impedes definitive conclusions from numerical methods such as harmonic balance. In this work, we establish a general existence criterion for quasi-periodically forced vibratory systems with nonlinear stiffness terms. Our criterion does not rely on any small parameters and hence is applicable for large response and forcing amplitudes. On explicit numerical examples, we demonstrate how our existence criterion can be utilized to justify subsequent numerical computations of forced responses.
Parametric vibrations of graphene sheets based on the double mode model and the nonlocal elasticity theory
Authors: Awrejcewicz Jan , Kudra Grzegorz , Mazur Olga
Published: July 2021

Parametric vibrations of the single-layered graphene sheet (SLGS) are studied in the presented work. The equations of motion govern geometrically nonlinear oscillations. The appearance of small effects is analysed due to the application of the nonlocal elasticity theory. The approach is developed for rectangular simply supported small-scale plate and it employs the Bubnov–Galerkin method with a double mode model, which reduces the problem to investigation of the system of the second-order ordinary differential equations (ODEs). The dynamic behaviour of the micro/nanoplate with varying excitation parameter is analysed to determine the chaotic regimes. As well the influence of small-scale effects to change the nature of vibrations is studied. The bifurcation diagrams, phase plots, Poincaré sections and the largest Lyapunov exponent are constructed and analysed. It is established that the use of nonlocal equations in the dynamic analysis of graphene sheets leads to a significant alteration in the character of oscillations, including the appearance of chaotic attractors.
Accounting for non-normal distribution of input variables and their correlations in robust optimization
Authors: Nejadseyfi O. , Geijselaers H. J. M. , Atzema E. H. , Abspoel M. , van den Boogaard A. H.
Published: July 2021

In this work, metamodel-based robust optimization is performed using measured scatter of noise variables. Principal component analysis is used to describe the input noise using linearly uncorrelated principal components. Some of these principal components follow a normal probability distribution, others however deviate from a normal probability distribution. In that case, for more accurate description of material scatter, a multimodal distribution is used. An analytical method is implemented to propagate the noise distribution via metamodel and to calculate the statistics of the response accurately and efficiently. The robust optimization criterion as well as the constraints evaluation are adjusted to properly deal with multimodal response. Two problems are presented to show the effectiveness of the proposed approach and to validate the method. A basketball free throw in windy weather condition and forming of B-pillar component are presented. The significance of accounting for non-normal distribution of input variables using multimodal distributions is investigated. Moreover, analytical calculation of response statistics, and adjustment of the robust optimization problem are presented and discussed.
The SN2 reaction and its relationship with the Walden inversion, the Finkelstein and Menshutkin reactions together with theoretical calculations for the Finkelstein reaction
Authors: Alkorta Ibon , Elguero José
Published: July 2021

This communication gives an overview of the relationships between four reactions that although related were not always perceived as such: SN2, Walden, Finkelstein, and Menshutkin. Binary interactions (SN2 & Walden, SN2 & Menshutkin, SN2 & Finkelstein, Walden & Menshutkin, Walden & Finkelstein, Menshutkin & Finkelstein) were reported. Carbon, silicon, nitrogen, and phosphorus as central atoms and fluorides, chlorides, bromides, and iodides as lateral atoms were considered. Theoretical calculations provide Gibbs free energies that were analyzed with linear models to obtain the halide contributions. The M06-2x DFT computational method and the 6-311++G(d,p) basis set have been used for all atoms except for iodine where the effective core potential def2-TZVP basis set was used. Concerning the central atom pairs, carbon/silicon vs. nitrogen/phosphorus, we reported here for the first time that the effect of valence expansion was known for Si but not for P. Concerning the lateral halogen atoms, some empirical models including the interaction between F and I as entering and leaving groups explain the Gibbs free energies.
Ten-year experience of an outpatient clinic for CKD-5 patients with multidisciplinary team and educational support
Authors: Terlizzi Vincenzo , Sandrini Massimo , Vizzardi Valerio , Tonoli Mattia , Facchini Annalisa , Manili Luigi , Zeni Letizia , Cancarini Giovanni
Published: July 2021

Purpose

To analyze the results of an outpatient clinic with a multidisciplinary team and educational support for patients with late-stage CKD (lsCKD), to check its possible effect on their outcomes.

Methods

Longitudinal cohort study on patients followed up in the MaReA (Malattia Renale Avanzata = CKD5) outpatient clinic at ASST Spedali Civili of Brescia from 2005 to 2015 for at least six months. Trajectory of renal function over time has been evaluated only in those patients with at least four estimations of eGFR before referring to MaReA.

Results

Seven hundred and six patients were enrolled, their mean age was 72 ± 14 years, 59% were males. At the end of the study, 147 (21%) were still on MaReA, 240 (34%) on dialysis, 92 (13%) on very low-protein diet (VLPDs), 13 (2%) on pre-hemodialysis clinic, 23 (3%) improved renal function, 10 (1%) transplanted, 62 (9%) transferred/lost to follow-up, and 119 (17%) died. Optimal dialysis start (defined as start with definitive dialysis access, as an out-patient and without lsCKD complications) occurred in 180/240 (75%) patients. The results showed a slower eGFR decrease during MaReA follow-up compared to previous renal follow-up: − 2.0 vs. − 4.0 mL/min/1.73 m2 BSA/year (p < 0.05), corresponding to a median delay of 17.7 months in dialysis start in reference to our policy in starting dialysis. The patient cumulative survival was 75% after 24 months and 25% after 70. Limitations: (1) lack of a control group, (2) one-center-study, (3) about all patients were Caucasians.

Conclusion

The follow-up of lsCKD patients on MaReA is associated with an optimal and delayed initiation of dialysis.
A systematic literature review concerning the different interpretations of the role of sustainability in project management
Authors: Friedrich Kevin
Published: July 2021

The concept of sustainable development is widely accepted as one of the most important topics of our time. Although significant research has already been conducted within the field of integrating sustainability into project management, different interpretations of the role of sustainability appear. This is a major issue for the scientific community, as due to these varying interpretations it is difficult to put publications into context; accordingly, it might lead to communication issues within the community. With this research study we want to help solve this issue. We conduct a systematic literature review and identify 293 relevant publications. Using a synthesis approach based on grounded theory, we define three different categories of interpretations of the role of sustainability in the current state of research. The literature is then assigned back to these interpretations. Following this approach we are not only able to review the development of each interpretation over time, but also to identify that many publications contain multiple interpretations. Based on our findings, we give recommendations for the reflection of the existing literature, the writing of new publications and communication in the research field. We also redefine the concept of ‘sustainable project management’ based on a major theoretical characteristic we synthesise during our grounded theory approach to give guidance to future researchers.
Preventing violence in youth sport and physical education: the NOVIS proposal
Authors: Vitali Francesca , Conte Salvatore
Published: July 2021

Background

Violence in sport, both on and off the field, has been conceived as a main social problem that needs to be prevented.

Aims

The purpose of this paper is to present in the ‘No Violence in Sport’ (NOVIS) project framework, a modular training model, some recommendations and tools that can be implemented in youth sport and physical education (PE) to prevent violence.

Methods

A modular training model summarized in a NOVIS methodological guide designed for coaches and PE teachers aimed at raising awareness on preventing violence and developing specific didactic skills to contrast violence is presented. Didactic recommendations to create a mastery (task-involving) motivational climate in youth sport and PE, interactive didactic methodologies and inclusion are the key elements of the modular training model. In addition, some multimedia didactic tools (i.e., sport chart, logbooks, cooperative games, and videos) are also presented.

Conclusions

The main aim of the NOVIS project was to develop teaching methodologies and tools focused at preventing violence in youth sport and PE. Future research is needed to implement the modular training model and to test it, evaluating its efficacy, expanding its aims, and adapting it to specific contexts and countries.
Assumptions and confidence of others: the impact of socio-cognitive information on metacognitive self-regulation
Authors: Schnaubert Lenka , Krukowski Simon , Bodemer Daniel
Published: July 2021

Self-regulated learning rarely happens in isolation and although there is a wide range of evidence that socio-cognitive information may impact decision making and learning, its role in metacognitive self-regulation remains understudied. Thus, we investigated how socio-cognitive information on assumptions and confidence in assumptions of an unknown other in a learning setting affects (1) changes in assumptions (i.e., convergence towards other), (2) perception of the other’s competence, and (3) the search for information (i.e., metacognitive and conflict-based regulation). In our empirical study, N = 60 students first read texts, then judged statements as being true or false and stated their confidence in these assumptions on an integrated confidence/answer scale, were then confronted with bogus information on the supposed answers of another learner (computer generated), and were then asked to (1) re-state their assumptions including confidence judgment, (2) judge the other’s competence, and (3) decide what statements they wanted additional information on. Results showed that learners (1) converged towards the other learner, (2) judged the other’s competence in accordance with the other’s stated confidence, and (3) regulated their learning based on their own (adjusted) confidence rather than on the presence or absence of socio-cognitive conflicts. This suggests that socio-cognitive information can affect how learners metacognitively evaluate own assumptions and thus impact self-regulatory processes, but also that confidence of others affects their perceived competence. Although the direct impact of socio-cognitive conflicts on regulatory processes remains unclear, this study fosters our understanding of self-regulated learning processes within social contexts.
Distribution profiles of diphenhydramine and lidocaine in scalp, axillary, and pubic hairs measured by micro-segmental hair analysis: good indicator for discrimination between administration and external contamination of the drugs
Authors: Kuwayama Kenji , Miyaguchi Hajime , Kanamori Tatsuyuki , Tsujikawa Kenji , Yamamuro Tadashi , Segawa Hiroki , Okada Yuki , Iwata Yuko T.
Published: July 2021

Purpose

Drug distribution in scalp hair can provide historical information about drug use, such as the date and frequency of drug ingestion. We previously developed micro-segmental hair analysis, which visualizes drug distribution at 0.4-mm intervals in individual hairs. The present study examines whether the distribution profiles of drugs can be markers for the administration or external contamination of the drugs using scalp, axillary, and pubic hairs.

Methods

A single dose of anti-itch ointment containing diphenhydramine (DP) and lidocaine (LD) was topically applied to the axillary or pubic areas of two volunteers; DP was also orally administered; and LD was intra-gingivally injected. Scalp, axillary, and pubic hairs were assessed using our micro-segmental analysis.

Results

The localization of DP and LD differed within individual scalp hair strands, implying DP and LD were predominantly incorporated into scalp hair via the bloodstream and via sweat/sebum, respectively, showing double-peak profiles. However, DP and LD were distributed along the shafts of axillary and pubic hairs without appearance of the double-peak profiles when the ointment had been applied to the axillary and pubic areas. The distributions of DP and LD in scalp hairs did not significantly differ according to administration routes, such as oral administration, gingival injection, and topical application.

Conclusions

Micro-segmental analysis revealed differences in the distribution profiles of drugs in hairs, and distinguished hairs with and without external contamination. These findings will be useful for understanding of the mechanism of drug uptake into hair and for estimating the circumstances for a drug use.
Effect of Surface Oxides on the Melting and Solidification of 316L Stainless Steel Powder for Additive Manufacturing
Authors: Yang Xinliang , Gao Feng , Tang Fengzai , Hao Xinjiang , Li Zushu
Published: July 2021

Surface oxidation of metallic powders may significantly affect their melting and solidification behavior and limit their service life in the additive manufacturing (AM) process. In the present work, three levels of surface oxide concentration were prepared on AM-grade 316L stainless steel powders, and their melting and solidification behavior was systematically studied through in-situ observation, advanced characterization, phase-field modeling, and theoretical analysis. Si, Mn, and Cr participated in the oxidation reaction in powder with low and medium oxygen contents, whereas Fe was involved in the oxidation reaction for the powder samples with high oxygen content. A higher full melting temperature is observed to lead to an integrated melt pool in the melting of the highly oxidized powder, which is due to the reduced permeability produced by the oxide cage effect. For the droplet samples prepared from high oxygen powders, the inclusion with increased volume fraction and coarsened size is attributed to the agglomeration of inclusion particles with the residual oxide in the melt. In the high oxygen powder fusion scenario, an undesired coarse columnar grain structure with a high aspect ratio is formed in the current nonequilibrium solidification process, and a consistent microstructure is predicted using solidification conditions with a high cooling rate and high thermal gradient similar to the conventional AM process. In contrast, fine equiaxed grains in the experiment and slim columnar grains with a small aspect ratio in the phase-field simulation are obtained for the low oxygen powder condition. This study illustrates the effect of powder oxide from a processing aspect and provides insight into the importance of improving the service life of powder feedstock by effectively reducing the surface oxidation process on the powder surface.
Microwave-Assisted Synthesis and Characterization of γ-MnO2 for High-Performance Supercapacitors
Authors: Cuéllar-Herrera Lorena , Arce-Estrada Elsa , Romero-Serrano Antonio , Ortiz-Landeros José , Cabrera-Sierra Román , Tirado-López Cindy , Hernández-Ramírez Aurelio , López-Rodríguez Josué
Published: July 2021

Two hydrothermal techniques under microwave irradiation were used to synthesize γ-MnO2 from 90°C to 150°C in 10−30 min. The first technique is based on reducing KMnO4 with MnSO4, and the second one involves liquid-phase oxidation between MnSO4 and (NH4)2S2O8. The structures and morphologies of the samples were analyzed using X-ray diffraction, scanning electron microscopy, and N2 physisorption measurements. The electrochemical properties were evaluated through cyclic voltammetry and electrochemical impedance spectroscopy. The γ-MnO2 materials obtained by the first technique mainly exhibited nanorods with diameters of 40–60 nm, and the samples obtained by the second technique showed flower-like microspheres with diameters of 1−2 µm; each flower was composed of nanosheets with a thickness of 10−20 nm. The processing time directly depends on the size of the nanorods. The sample synthesized by the first technique at 150°C and 10 min has the highest specific surface area of up to 59.08 m2 g−1 and mean pore diameter of 34.11 nm. Furthermore, this sample exhibits a near-rectangular cyclic voltammetry curves and high specific capacitance of 331.3 F g−1 in 0.1 M Na2SO4 solution at 5 mV s−1 scan rate.

Graphic abstract
Comparison of Conventional Methods for Bowel Length Measurement in Laparoscopic Surgery to a Novel Computer-Assisted 3D Measurement System
Authors: Wagner Martin , Mayer Benjamin F. B. , Bodenstedt Sebastian , Kowalewski Karl-Friedrich , Nickel Felix , Speidel Stefanie , Fischer Lars , Kenngott Hannes G. , Müller-Stich Beat-Peter
Published: July 2021

Purpose

Accurate laparoscopic bowel length measurement (LBLM), which is used primarily in metabolic surgery, remains a challenge. This study aims to three conventional methods for LBLM, namely using visual judgment (VJ), instrument markings (IM), or premeasured tape (PT) to a novel computer-assisted 3D measurement system (BMS).

Materials and Methods

LBLM methods were compared using a 3D laparoscope on bowel phantoms regarding accuracy (relative error in percent, %), time in seconds (s), and number of bowel grasps. Seventy centimeters were measured seven times. As a control, the first, third, fifth, and seventh measurements were performed with VJ. The interventions IM, PT, and BMS were performed following a randomized order as the second, fourth, and sixth measurements.

Results

In total, 63 people participated. BMS showed better accuracy (2.1±3.7%) compared to VJ (8.7±13.7%, p=0.001), PT (4.3±6.8%, p=0.002), and IM (11±15.3%, p<0.001). Participants performed LBLM in a similar amount of time with BMS (175.7±59.7s) and PT (166.5±63.6s, p=0.35), but VJ (64.0±24.0s, p<0.001) and IM (144.9±55.4s, p=0.002) were faster. Number of bowel grasps as a measure for the risk of bowel lesions was similar for BMS (15.8±3.0) and PT (15.9±4.6, p=0.861), whereas VJ required less (14.1±3.4, p=0.004) and IM required more than BMS (22.2±6.9, p<0.001).

Conclusions

PT had higher accuracy than VJ and IM, and lower number of bowel grasps than IM. BMS shows great potential for more reliable LBLM. Until BMS is available in clinical routine, PT should be preferred for LBLM.

Graphical abstract
Antioxidant Activities and Selenogene Transcription in the European Sea Bass (Dicentrarchus labrax) Liver Depend, in a Non-linear Manner, on the Se/Hg Molar Ratio of the Feeds
Authors: Espino Marinelle , Eguiraun Harkaitz , Diaz de Cerio Oihane , Carrero José Antonio , Etxebarria Nestor , Martinez Iciar
Published: July 2021

Feeding 3.9 and 6.7 mg Hg/kg (Se/Hg molar ratios of 0.8 and 0.4, respectively) for 14 days negatively affected Dicentrarchus labrax growth and total DNTB- and thioredoxin-reductase (TrxR) activities and the transcription of four redox genes (txn1, gpx1, txnrd3, and txnrd2) in the liver, but a diet with 0.5 mg Hg/kg (Se/Hg molar ratio 6.6) slightly increased both reductase activities and the transcription of txn1, gpx1, and txnrd2. Feeding 6.7 mg Hg/kg for 53 days downregulated the genes of the thioredoxin system (txn1, txnrd3, and txnrd2) but upregulated gpx1, confirming the previously proposed complementarity among the antioxidant systems. Substitution of 20% of the feed by thawed white fish (hake) slightly counteracted the negative effects of Hg. The effects were not statistically significant and were dependent, in a non-linear manner, on the Se/Hg molar ratio of the feed but not on its Hg concentration. These results stress the need to consider the Se/Hg molar ratio of the feed/food when evaluating the toxicity of Hg.
The Health Risk Assessment of Essential Elemental Impurities (Cu, Mn and Zn) Through the Dermal Exposure of Herbal Ointment Extracted from Marjoram Herb (Majoranae herbae extractum)
Authors: Jurowski Kamil , Fołta Maria , Tatar Barbara , Berkoz Mehmet , Krośniak Mirosław
Published: July 2021

Essential elements like Cu, Mn and Zn are extremely important for herbs’ growth and physiological functions; however, from a toxicological point of view, the exposure of these elements (as essential elemental impurities) can exhibit potential harmful effects for patients. In Europe, very popular are ointments with Marjoram herb extract (Majoranae herbae extractum) as herbal medicinal products for adjunctively in rhinitis (runny nose). Based on posology of ointments with Marjoram herb extract, the exposure to these elemental impurities may be high during long-term use. Hence, the aim of this article is the health risk assessment of essential elemental impurities (Cu, Mn and Zn) through the dermal exposure of ointments with Marjoram herb extract (Majoranae herbae extractum) as herbal medicinal products applied adjunctively in rhinitis available in Polish pharmacies. The investigated essential elements were determined by well-validated methodology (R > 0.997, recoveries, LOD and LOQ values were acceptable) based on flame atomic absorption spectrometry (FAAS). Our results indicated that all analysed herbal medicinal products with Marjoram herb extract available in Polish pharmacies contain relatively low levels of essential element impurities, i.e. Cu (0.14–0.49 mg/kg), Mn (0.31–2.57 mg/kg) and Zn (0.73–3.19 mg/kg). The estimated exposure of the investigated elemental impurities confirms the safety of all products. To the best of our knowledge, the study about Cu, Mn and Zn contents in HMPs with Majoranae herbae extractum is described for the first time. The applied methodology and results are extremely important from regulatory toxicology point of view due to ICH Q3D elemental impurity guideline for pharmaceuticals.
Integration of the buyer–supplier interface for Global sourcing
Authors: Bals Lydia , Turkulainen Virpi
Published: July 2021

While global sourcing often implies that the firm needs to, for example, redesign the procurement organization and make decisions on what to centralize and what to manage locally, global sourcing also has direct implications for management of the buyer–supplier interface. This study takes an organization design focus and addresses global sourcing organization design as well as provides illustrations on how to integrate the buyer–supplier interface for global sourcing. Integration is conceptualized as coordination and cooperation. The paper is based on an embedded unit case study of a global technical industrial product and service systems provider, TechInd (pseudonym). Data was collected from TechInd as well as from six of its suppliers. The findings indicate that the global sourcing organization structure, as well as the differences in the buyer’s sourcing and supplier’s sales organizations, pose requirements for management of the interface in terms of coordination and cooperation. Challenges arising particularly due to differences in geographical scope and level of centralization can be managed by introducing the key account role and alignment of incentives.
The role of preservice teachers’ implicit attitudes and causal attributions: a deeper look into students’ ethnicity
Authors: Glock Sabine , Kleen Hannah
Published: July 2021

Previous research has provided evidence that teachers implicitly hold more negative attitudes toward ethnic minority students than toward ethnic majority students. Furthermore, they attribute the lower educational success of ethnic minority students predominantly to internal causes. So far, it is not known how implicit attitudes and causal attributions are related to preservice teachers’ judgments of students’ academic competencies. We conducted a study to close this research gap. In a sample of preservice teachers, our study showed mainly negative implicit attitudes toward ethnic minority students. On general, the preservice teachers made external attributions. Implicit attitudes as well as causal attributions predicted the judgments. Preservice teachers with more negative attitudes and preservice teachers, who attributed the failure of ethnic minority students to these students’ abilities, less favorably judged the competence of ethnic minority students. Our results highlight the role of teachers’ attitudes and causal attributions in determining the disadvantages that ethnic minority students experience in school.
From HRI to CRI: Crowd Robot Interaction—Understanding the Effect of Robots on Crowd Motion
Authors: Zhang Bingqing , Amirian Javad , Eberle Harry , Pettré Julien , Holloway Catherine , Carlson Tom
Published: July 2021

How does the presence of a robot affect pedestrians and crowd dynamics, and does this influence vary across robot type? In this paper, we took the first step towards answering this question by performing a crowd-robot gate-crossing experiment. The study involved 28 participants and two distinct robot representatives: A smart wheelchair and a Pepper humanoid robot. Collected data includes: video recordings; robot and participant trajectories; and participants’ responses to post-interaction questionnaires. Quantitative analysis on the trajectories suggests the robot affects crowd dynamics in terms of trajectory regularity and interaction complexity. Qualitative results indicate that pedestrians tend to be more conservative and follow “social rules” while passing a wheelchair compared to a humanoid robot. These insights can be used to design a social navigation strategy that allows more natural interaction by considering the robot effect on the crowd dynamics.
Pteridophytes as primary colonisers after catastrophic events through geological time and in recent history
Authors: Thomas Barry A. , Cleal Christopher J.
Published: July 2021

Pteridophytes reproduce by producing vast numbers of spores that may be dispersed over considerable distances, helping the plants colonise new areas. Being resistant to desiccation, fern spores can often survive for many years as spore banks in soil. After disturbance, such spores can germinate and subsequently colonise the area. These factors help pteridophytes to become primary colonisers on barren land, such as volcanic islands or land that has been devastated by some cataclysmic event. A further method of rapid colonisation is provided through the preservation and possible scattering of fragments of rhizomes in particular of horsetails. Similar rapid colonising by pteridophytes has been documented in the geological record following several major extinction events. These distinct, but short-lived, fern populations are recognisable by fern spikes in the microfossils. This paper brings together information on the reasons for pteridophyte success in colonising barren land, and examples taken from both the historic and geological records.
Ras isoform-specific expression, chromatin accessibility, and signaling
Authors: Nussinov Ruth , Zhang Mingzhen , Maloney Ryan , Jang Hyunbum
Published: July 2021

The anchorage of Ras isoforms in the membrane and their nanocluster formations have been studied extensively, including their detailed interactions, sizes, preferred membrane environments, chemistry, and geometry. However, the staggering challenge of their epigenetics and chromatin accessibility in distinct cell states and types, which we propose is a major factor determining their specific expression, still awaits unraveling. Ras isoforms are distinguished by their C-terminal hypervariable region (HVR) which acts in intracellular transport, regulation, and membrane anchorage. Here, we review some isoform-specific activities at the plasma membrane from a structural dynamic standpoint. Inspired by physics and chemistry, we recognize that understanding functional specificity requires insight into how biomolecules can organize themselves in different cellular environments. Within this framework, we suggest that isoform-specific expression may largely be controlled by the chromatin density and physical compaction, which allow (or curb) access to “chromatinized DNA.” Genes are preferentially expressed in tissues: proteins expressed in pancreatic cells may not be equally expressed in lung cells. It is the rule—not an exception, and it can be at least partly understood in terms of chromatin organization and accessibility state. Genes are expressed when they can be sufficiently exposed to the transcription machinery, and they are less so when they are persistently buried in dense chromatin. Notably, chromatin accessibility can similarly determine expression of drug resistance genes.
LIN28 coordinately promotes nucleolar/ribosomal functions and represses the 2C-like transcriptional program in pluripotent stem cells
Authors: Sun Zhen , Yu Hua , Zhao Jing , Tan Tianyu , Pan Hongru , Zhu Yuqing , Chen Lang , Zhang Cheng , Zhang Li , Lei Anhua , Xu Yuyan , Bi Xianju , Huang Xin , Gao Bo , Wang Longfei , Correia Cristina , Chen Ming , Sun Qiming , Feng Yu , Shen Li , Wu Hao , Wang Jianlong , Shen Xiaohua , Daley George Q. , Li Hu , Zhang Jin
Published: July 2021

LIN28 is an RNA binding protein with important roles in early embryo development, stem cell differentiation/reprogramming, tumorigenesis and metabolism. Previous studies have focused mainly on its role in the cytosol where it interacts withLet-7microRNA precursors or mRNAs, and few have addressed LIN28’s role within the nucleus. Here, we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development. Maternal LIN28 expression drops upon exit from the 2-cell stage, and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blastocyst stage development, to become dominantly expressed in the cytosol after implantation. In cultured pluripotent stem cells (PSCs), loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes. Mechanistically, LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity, and its loss leads to nucleolar phase separation defects, ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factorDux. LIN28 also resides in a complex containing the nucleolar factor Nucleolin (NCL) and the transcriptional repressor TRIM28, and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on theDuxand rDNA loci, and thus de-repressedDuxand reduced rRNA expression.Lin28knockout cells with nucleolar stress are more likely to assume a slowly cycling, translationally inert and anabolically inactive state, which is a part of previously unappreciated 2C-like transcriptional program. These findings elucidate novel roles for nucleolar LIN28 in PSCs, and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.
Starlike functions associated with the generalized Koebe function
Authors: Kargar Rahim , Trojnar-Spelina Lucyna
Published: July 2021

In this paper we study some properties of functions f which are analytic and normalized (i.e. $$f(0)=0=f'(0)-1$$

f

(
0
)

=
0
=

f
′

(
0
)

-
1

) such that satisfy the following subordination relation $$\begin{aligned} \left( \frac{zf'(z)}{f(z)}-1\right) \prec \frac{z}{(1-pz)(1-qz)}, \end{aligned}$$

z

f
′

(
z
)

f
(
z
)

-
1

≺

z

(
1
-
p
z
)
(
1
-
q
z
)

,

where $$(p,q) \in [-1,1] \times [-1,1]$$

(
p
,
q
)
∈
[
-
1
,
1
]
×
[
-
1
,
1
]

. These types of functions are starlike related to the generalized Koebe function. Some of the features are: radius of starlikeness of order $$\gamma \in [0,1)$$

γ
∈
[
0
,
1
)

, image of $$f\left( \{z:|z|<r\}\right) $$

f

{
z
:
|
z
|
<
r
}

where $$r\in (0,1)$$

r
∈
(
0
,
1
)

, radius of convexity, estimation of initial and logarithmic coefficients, and Fekete–Szegö problem.
An algorithm for Parkinson’s disease speech classification based on isolated words analysis
Authors: Amato Federica , Borzì Luigi , Olmo Gabriella , Orozco-Arroyave Juan Rafael
Published: July 2021

Introduction

Automatic assessment of speech impairment is a cutting edge topic in Parkinson’s disease (PD). Language disorders are known to occur several years earlier than typical motor symptoms, thus speech analysis may contribute to the early diagnosis of the disease. Moreover, the remote monitoring of dysphonia could allow achieving an effective follow-up of PD clinical condition, possibly performed in the home environment.

Methods

In this work, we performed a multi-level analysis, progressively combining features extracted from the entire signal, the voiced segments, and the on-set/off-set regions, leading to a total number of 126 features. Furthermore, we compared the performance of early and late feature fusion schemes, aiming to identify the best model configuration and taking advantage of having 25 isolated words pronounced by each subject. We employed data from the PC-GITA database (50 healthy controls and 50 PD patients) for validation and testing.

Results

We implemented an optimized k-Nearest Neighbours model for the binary classification of PD patients versus healthy controls. We achieved an accuracy of 99.4% in 10-fold cross-validation and 94.3% in testing on the PC-GITA database (average value of male and female subjects).

Conclusion

The promising performance yielded by our model confirms the feasibility of automatic assessment of PD using voice recordings. Moreover, a post-hoc analysis of the most relevant features discloses the option of voice processing using a simple smartphone application.
Elimination of Viral Hepatitis in Low and Middle-Income Countries: Epidemiological Research Gaps
Authors: Jaquet Antoine , Muula Guy , Ekouevi Didier K. , Wandeler Gilles
Published: July 2021

Purpose of Review

The purpose of our review was to summarize current recommendations on testing strategies, antiviral therapy eligibility and monitoring, and prevention of mother-to-child transmission of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, and to highlight major research gaps in low and middle-income countries (LMIC), with a particular focus on sub-Saharan Africa (SSA).

Recent Findings

While data on the prevalence of HBV and HCV infections in LMIC are increasing, current knowledge on liver-related complications as well as on treatment outcomes remains limited. Furthermore, very little information is available on the feasibility and cost-effectiveness of large-scale testing and management strategies in high-prevalence settings. The availability of policy-relevant data is particularly scarce in SSA, which accounts for a significant part of the global burden of chronic viral hepatitis.

Current recommendations on the management and monitoring of chronic viral hepatitis rely mainly on data from high-income settings. The global elimination of viral hepatitis will only be achieved if prevention, testing, and treatment strategies tailored to specific LMIC are implemented. In order to inform scalable and cost-effective interventions, dedicated research initiatives have to be undertaken. Future studies will have to include the evaluation of innovative testing strategies, the validation of simplified methods to diagnose liver cirrhosis and hepatocellular carcinoma, and the monitoring of long-term treatment outcomes and toxicity. In addition, national plans to achieve the elimination of HBV mother-to-child transmission are urgently needed, including effective ways to test pregnant women, treat those who are eligible, and ensure birth dose vaccination is given to all newborns.
EHEFT-R: multi-objective task scheduling scheme in cloud computing
Authors: Zhang Honglin , Wu Yaohua , Sun Zaixing
Published: July 2021

In cloud computing, task scheduling and resource allocation are the two core issues of the IaaS layer. Efficient task scheduling algorithm can improve the matching efficiency between tasks and resources. In this paper, an enhanced heterogeneous earliest finish time based on rule (EHEFT-R) task scheduling algorithm is proposed to optimize task execution efficiency, quality of service (QoS) and energy consumption. In EHEFT-R, ordering rules based on priority constraints are used to optimize the quality of the initial solution, and the enhanced heterogeneous earliest finish time (HEFT) algorithm is used to ensure the global performance of the solution space. Simulation experiments verify the effectiveness and superiority of EHEFT-R.
Using context-dependent DEA to analyze the efficiency of highly funded scientists in China
Authors: Xiang Keyu , Liang Haiming , Guo Zhaoxia , Dong Yucheng
Published: July 2021

Funding inputs and research outputs have always been two central issues in the science of science. In recent decades, research funding plays an increasingly important role in scientific research. Thus, it is progressively significant for management authorities to measure the research efficiency of highly funded scientists, which can be helpful for them to make effective policies. However, few researchers use quantitative analysis to study these issues. To promote the research in this field, we begin with collecting a dataset. This dataset contains research funding and other information from 345 highly funded scientists in Mainland China. Next, we use the dataset to measure the efficiency of highly funded scientists based on the data envelopment analysis. In this way, highly funded scientists are placed into several levels according to their research inputs and outputs. We also give their attractiveness and progress scores compared to other grades. The learning path for less efficient scientists is also provided. We find that highly funded scientists have relatively high efficiency in three kinds of projects, such as the Major Research Plan. Besides, the career length and career start year are demonstrated to have a limited impact on the highly funded scientists. These patterns are beneficial for the development of the scientific community and management authorities to make policies.
A survey on computation resource allocation in IoT enabled vehicular edge computing
Authors: Naren  , Gaurav Abhishek Kumar , Sahu Nishad , Dash Abhinash Prasad , Chalapathi G. S. S. , Chamola Vinay
Published: July 2021

The number of vehicles is increasing at a very high rate throughout the globe. It reached 1 billion in 2010, in 2020 it was around 1.5 billion and experts say this could reach up to 2–2.5 billion by 2050. A large part of these vehicles will be electrically driven and connected to a vehicular network. Rapid advancements in vehicular technology and communications have led to the evolution of vehicular edge computing (VEC). Computation resource allocation is a vehicular network’s primary operations as vehicles have limited onboard computation. Different resource allocation schemes in VEC operate in different environments such as cloud computing, artificial intelligence, blockchain, software defined networks and require specific network performance characteristics for their operations to achieve maximum efficiency. At present, researchers have proposed numerous computation resource allocation schemes which optimize parameters such as power consumption, network stability, quality of service (QoS), etc. These schemes are based on widely used optimization and mathematical models such as the Markov process, Shannon’s law, etc. So, there is a need to present an organized overview of these schemes to help in the future research of the same. In this paper, we classify state-of-the-art computation resource allocation schemes based on three criteria: (1) Their optimization goal, (2) Mathematical models/algorithms used, and (3) Major technologies involved. We also identify and discuss current issues in computation resource allocation in VEC and mention the future research directions.
Enhancing hierarchical surrogate-assisted evolutionary algorithm for high-dimensional expensive optimization via random projection
Authors: Ren Xiaodong , Guo Daofu , Ren Zhigang , Liang Yongsheng , Chen An
Published: July 2021

By remarkably reducing real fitness evaluations, surrogate-assisted evolutionary algorithms (SAEAs), especially hierarchical SAEAs, have been shown to be effective in solving computationally expensive optimization problems. The success of hierarchical SAEAs mainly profits from the potential benefit of their global surrogate models known as “blessing of uncertainty” and the high accuracy of local models. However, their performance leaves room for improvement on high-dimensional problems since now it is still challenging to build accurate enough local models due to the huge solution space. Directing against this issue, this study proposes a new hierarchical SAEA by training local surrogate models with the help of the random projection technique. Instead of executing training in the original high-dimensional solution space, the new algorithm first randomly projects training samples onto a set of low-dimensional subspaces, then trains a surrogate model in each subspace, and finally achieves evaluations of candidate solutions by averaging the resulting models. Experimental results on seven benchmark functions of 100 and 200 dimensions demonstrate that random projection can significantly improve the accuracy of local surrogate models and the new proposed hierarchical SAEA possesses an obvious edge over state-of-the-art SAEAs.
Adverse Events Following COVISHIELD Vaccination Among Adult Population in Bangladesh
Authors: Khalil Md. Musab , Mahbub-Uz-Zaman Khandker , Hossain As-Saba , Ahmed Farid , Chowdhury Md. Fazlul Karim , Khan Sharmin Tahmina , Miah Md. Shah Alam , Khaleque Narwana , Kibria Md. Golam , Ahmed Faruque , Khan Ahad Mahmud
Published: July 2021

The study aimed to determine how frequently the adverse events of the COVISHIELD vaccine occur among the Bangladeshi population. This cross-sectional study was conducted at Sheikh Russel Gastroliver Institute and Hospital, Mohakhali, Dhaka, Bangladesh, in May 2021. The inclusion criteria were the adult populations who received the 2nd dose of the COVISHELD vaccine and had passed 28 days following the completion of the 2nd dose. Three hundred and five persons fulfilling the inclusion criteria were asked over the telephone—based on a predesigned questionnaire. The rates of adverse events were 54.1% and 41.3% after the 1st and 2nd dose of vaccine, respectively, and the difference was statistically significant (p < 0.001). Pain at the injection site was the most common adverse event (32.5% following the 1st dose and 27.9% following the 2nd dose). All of the symptoms were mild and lasted for about 2 days. Age and comorbidities were significantly associated with the adverse events (p < 0.001). Neither doses had any vaccine-related life-threatening adverse event nor had any symptoms related to vaccine-related blood clotting. Nineteen persons (6.2%) had been diagnosed with COVID-19 after the 1st dose of vaccination, and three (1%) persons had been diagnosed with COVID-19 after the 2nd dose of vaccination. As no significant life-threatening adverse event was observed, this study might help reduce the hesitancy for vaccination among the population and thus help reduce transmission of this highly contagious virus.
Mixed Kane–Newton Multi-Body Analysis of a Dual-Arm Robotic System for On-Orbit Servicing Missions
Authors: De Bonis Alex , Angeletti Federica , Iannelli Paolo , Gasbarri Paolo
Published: July 2021

A currently relevant topic is the development of on-orbit servicing missions designed to repair, refuel or deorbit non-co-operative spacecraft. For this purpose, it is possible to use space robotic systems composed of a main platform and one or more robotic arms. In this paper, the capacity of a dual-arm robotic system to manipulate and to deorbit a generic target will be analyzed. For this purpose, a mixed Kane–Newton multi-body model will be implemented; this model will allow to switch automatically from an open-chain configuration (target captured via a single robotic arm) to a closed-chain configuration (target captured via both robotic arms) and vice versa. The flexibility of the joints of the system and the flexibility of the components of the robotic arms will be considered in the model. The system will be properly sized to operate the deorbiting of the target. Under the hypothesis of planar motion, numerical results will be presented to validate the model and to demonstrate the correct sizing of the system.