bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovative fabrication of diffractive surfaces on plastic parts via textures micromilled on NiP injection moulds
Authors: Milan Nicola , Parenti Paolo , Annoni Massimiliano , Sorgato Marco , Lucchetta Giovanni
Published: February 2021

Diffractive microstructured surfaces are nowadays increasingly applied to polymeric parts for aesthetic, security and optical functionalities. However, both the machining of the mould blaze-grating and its replication on plastic are still representing challenging issues, from both the technical and economical points of view. In this work, an innovative process chain based on carbide tools micromilling of mould gratings was developed for mass production of diffractive patterns on injection moulded parts. A micromilling experimental campaign was conducted on a nickel-phosphorus (NiP) thick coating to machine a blaze-grating on the mould surface, evaluating the influence of the cutting parameters on the diffractive surface quality. Subsequently, the microstructures were replicated on ABS, PC and PMMA by injection moulding. The roughness parameters Sk, Spk and Svk were added with the idea that their sum is representative of the polymer replication of regular diffraction grating pattern. Moreover, the effect of the moulded grating surface quality on the optical performance was preliminarily assessed. The obtained results show that the proposed process chain is suitable for low-cost mass production of polymeric parts with diffractive microstructures.
Intertidal mussel reefs change the composition and size distribution of diatoms in the biofilm
Authors: Andriana Rosyta , Engel Friederike G. , Gusmao Joao B. , Eriksson Britas Klemens
Published: February 2021

Migrating diatoms are microscopic ecosystem engineering organisms that have functional consequences on the seascape scale by significantly contributing to the microphytobenthos biofilm. The microphytobenthos biofilm is a thin photosynthesising layer that covers the sediment on intertidal flats. It fuels the food web, increases sediment stability, and enhances the deposition of particles, providing ecosystem services to coastal communities. Here we tested the effect of another ecosystem engineering habitat, intertidal blue mussel reefs, on the composition and properties of migrating diatom communities. Small-scale reefs constructed in the intertidal mimicked and reinforced the natural pattern in diatom community composition and function that we documented in the field. The field experiment adding small reefs to the intertidal ran from 30 April to 10 June 2015 and the field samples were collected around a natural blue mussel bed on the same tidal flat on 7 October 2015 (N 53.489°, E 6.230°). Both the constructed small-scale reefs and the natural reef changed the community composition of diatoms in the biofilm by promoting higher numbers of smaller-sized cells and species. Small diatoms have higher growth and gross photosynthesis rates, indicating that this explains the higher production and chlorophyll-a concentration of the biofilm measured on natural intertidal shellfish reefs. Our results showed that shellfish reefs have a large impact on biofilm functioning. However, biofilms are also fuel for the shellfish, indicating that the two very different ecosystem engineers may facilitate coexistence on tidal flats through a positive feedback loop.
Platelet-expressed immune checkpoint regulator GITRL in breast cancer
Authors: Zhou Yanjun , Heitmann Jonas S. , Clar Kim L. , Kropp Korbinian N. , Hinterleitner Martina , Engler Tobias , Koch André , Hartkopf Andreas D. , Zender Lars , Salih Helmut R. , Maurer Stefanie , Hinterleitner Clemens
Published: February 2021

Owing to their key role in several diseases including cancer, activating and inhibitory immune checkpoint molecules are increasingly exploited as targets for immunotherapy. Recently, we demonstrated that platelets, which largely influence tumor progression and immune evasion, functionally express the ligand of the checkpoint molecule GITR. This immunoreceptor modulates effector functions of T cells and NK cells with its function varying dependent on cellular context and activation state. Here, we provide a comparative analysis of platelet-derived GITRL (pGITRL) in breast cancer patients and healthy volunteers. The levels of pGITRL were found to be higher on platelets derived from cancer patients and appeared to be specifically regulated during tumor progression as exemplified by several clinical parameters including tumor stage/grade, the occurrence of metastases and tumor proliferation (Ki67) index. In addition, we report that pGITRL is upregulated during platelet maturation and particularly induced upon exposure to tumor-derived soluble factors. Our data indicate that platelets modulate the GITR/GITRL immune checkpoint in the context of malignant disease and provide a rationale to further study the GITR/GITRL axis for exploitation for immunotherapeutic intervention in cancer patients.
Unusual shallow water Devonian coral community from Queensland and its recent analogues from the inshore Great Barrier Reef
Authors: Zapalski Mikołaj K. , Baird Andrew H. , Bridge Tom , Jakubowicz Michał , Daniell James
Published: February 2021

Palaeozoic coral communities were dominated by two extinct coral groups: Tabulata and Rugosa. Whilst they are not closely related to modern Scleractinia, they are morphologically convergent, displaying many morphological characters that allow comparisons between recent and ancient coral reef communities. The extensive shallow-water reef communities of the Devonian were generally dominated by stromatoporoid sponges, with corals occupying deeper environments. Here, we describe an unusual, shallow water coral reef community from the Middle Devonian (Givetian, approx. 385 Ma) of the Fanning River area, Queensland, Australia. The coral community is dominated by tabulate corals, but also includes solitary and occasionally colonial rugose corals. Tabulate corals most commonly exhibit foliose and massive morphologies, but encrusting and branching growth forms also occur. The depositional environment was characterized by a shallow water depth, moderate hydrodynamic energy, high sedimentation rate, and high turbidity. Since these environmental factors influence the morphological composition of modern coral communities, we hypothesize that similar environments may result in morphologically equivalent coral assemblages throughout the Phanerozoic. To test this idea, we qualitatively compare the Fanning River reefs with modern scleractinian coral assemblages in a similar environmental setting at Magnetic Island. Both reefs are located in a shallow water less than 10 m deep, with high sediment flux, moderate wave energy, and generally high turbidity. Like Fanning River, Magnetic Island coral communities are dominated by foliose morphologies, with contributions from massive and branching forms. The Fanning River reef, together with previously identified Silurian and Devonian mesophotic coral ecosystems, suggest that Palaeozoic coral assemblages may share many functional characteristics with modern scleractinian reefs in similar environments. Therefore, the geological record of inshore, high turbidity-adapted coral communities can be traced back as far as 385 Ma.
Quantifying the influence of natural climate variability on in situ measurements of seasonal total and extreme daily precipitation
Authors: Risser Mark D. , Wehner Michael F. , O’Brien John P. , Patricola Christina M. , O’Brien Travis A. , Collins William D. , Paciorek Christopher J. , Huang Huanping
Published: February 2021

While various studies explore the relationship between individual sources of climate variability and extreme precipitation, there is a need for improved understanding of how these physical phenomena simultaneously influence precipitation in the observational record across the contiguous United States. In this work, we introduce a single framework for characterizing the historical signal (anthropogenic forcing) and noise (natural variability) in seasonal mean and extreme precipitation. An important aspect of our analysis is that we simultaneously isolate the individual effects of seven modes of variability while explicitly controlling for joint inter-mode relationships. Our method utilizes a spatial statistical component that uses in situ measurements to resolve relationships to their native scales; furthermore, we use a data-driven procedure to robustly determine statistical significance. In Part I of this work we focus on natural climate variability: detection is mostly limited to DJF and SON for the modes of variability considered, with the El Niño/Southern Oscillation, the Pacific–North American pattern, and the North Atlantic Oscillation exhibiting the largest influence. Across all climate indices considered, the signals are larger and can be detected more clearly for seasonal total versus extreme precipitation. We are able to detect at least some significant relationships in all seasons in spite of extremely large (> 95%) background variability in both mean and extreme precipitation. Furthermore, we specifically quantify how the spatial aspect of our analysis reduces uncertainty and increases detection of statistical significance while also discovering results that quantify the complex interconnected relationships between climate drivers and seasonal precipitation.
Treatment of advanced stage osteochondrosis dissecans in the adolescent elbow using a hyaloronic acid-based scaffold: a case series of 5 patients
Authors: Farr Sebastian , Pallamar Matthias , Eder Theresa , Ganger Rudolf
Published: February 2021

Introduction

Osteochondrosis dissecans (OCD) is considered to be one of the main causes for pain, discomfort and morbidity in the pediatric elbow joint. Few treatment options, such as microfracture or autologous transplantation, of osteochondral bone grafts have been described to address advanced OCD. The aim of this retrospective case series is to present preliminary clinical and radiologic findings following advanced stage OCD repair using a novel combination of a hyaluronic acid-based scaffold with autologous iliac crest bone grafting.

Materials and methods

Five adolescents, who underwent treatment of OCD (grade 3 or 4 according to Nelson) using a combination technique of defect debridement, transplantation of cancellous iliac crest bone and application of a HYALOFAST® membrane (Anika Therapeutics S.r.L., Italy), were re-assessed using clinical and radiologic examinations (defect diameter, depth, sclerosis, congruency, fragmentation, dissection, radiolucency, growth plate status; MRI) after a minimum of 2 years (mean, 34 months; range, 24–45) postoperatively. Dedicated outcome scores (Numeric Rating Scale [NRS], Pediatric Outcome Data Collection Instrument [PODCI], Mayo Elbow Performance Score [MEPS], and Timmerman-Andrews Score [TIMM] were collected.

Results

All patients reported a NRS score of 0. The mean total TIMM, MEPS and PODCI (Global Functioning Scale) scores were 189 (range 165–200), 94 (range, 70–100), and 92 (range 83–98; normative score 47; range 35–55), respectively, indicating good to excellent clinical outcomes. The radiographic analysis showed overall improvements with regard to OCD width and depth reduction (35%, − 27–100%; 52%, 4–100%), but full resolution in only 2 of 5 cases. Elbow motion improved slightly after surgery. No complications were noted.

Conclusion

This study showed promising clinical short- to mid-term results in adolescent patients with advanced OCD using a novel surgical treatment combination. Radiographic results showed partial healing; hence, residual changes should be monitored over a longer period.
Effects of tranexamic acid on human nasal ciliary beat frequency
Authors: Behr W. , Horschke F. , Nastev A. , Mueller C. E. , Sommer J. U. , Folz B. , Li H. , Geisthoff U. W. , Stuck B. A. , Birk R.
Published: February 2021

Background

Patients with recurrent epistaxis, particularly due to hereditary hemorrhagic telangiectasia (HHT) are recommended to apply topical tranexamic acid (TXA) to reduce bleeding events. Those patients may suffer ciliary dysfunction due to TXA’s effects on ciliary beating frequency (CBF) and their consequences.

Methodology/principal

Human nasal epithelial cells were harvested with a nasal brush in 30 healthy subjects. We investigated the CBF in RPMI medium using high-frequency video microscopy. TXA was added to the cells in various concentrations ranging from 2 to 5%, including the therapeutic concentration (2%) and a control (0%).

Results

CBF in the control condition was 6.1 ± 1.6 Hz. TXA reduces CBF in a time and concentration dependent manner, to, e.g. 4.3 ± 1.2 Hz with 2% TXA and 3.3 ± 0.9 Hz with 5% TXA after 16–20 min. The differences in CBF were statistically significant for all concentrations of TXA.

Conclusions

TXA has the potential to significantly impair nasal epithelial function. Therefore, frequent or regular topical nasal application of TXA should be done under close monitoring of nasal function, especially in patients with co-morbidities like chronic rhinosinusitis.
A 25-year retrospective, single center analysis of 343 WHO grade II/III glioma patients: implications for grading and temozolomide therapy
Authors: Steidl Eike , Filipski Katharina , Zeiner Pia S. , Wagner Marlies , Fokas Emmanouil , Forster Marie-Therese , Ronellenfitsch Michael W. , Divé Iris , Steinbach Joachim P. , Harter Patrick N. , Bähr Oliver
Published: February 2021

Purpose

Classification and treatment of WHO grade II/III gliomas have dramatically changed. Implementing molecular markers into the WHO classification raised discussions about the significance of grading and clinical trials showed overall survival (OS) benefits for combined radiochemotherapy. As molecularly stratified treatment data outside clinical trials are scarce, we conducted this retrospective study.

Methods

We identified 343 patients (1995–2015) with newly diagnosed WHO grade II/III gliomas and analyzed molecular markers, patient characteristics, symptoms, histology, treatment, time to treatment failure (TTF) and OS.

Results

IDH-status was available for all patients (259 mutant, 84 IDH1-R132H-non-mutant). Molecular subclassification was possible in 173 tumors, resulting in diagnosis of 80 astrocytomas and 93 oligodendrogliomas. WHO grading remained significant for OS in astrocytomas/IDH1-R132H-non-mutant gliomas (p < 0.01) but not for oligodendroglioma (p = 0.27). Chemotherapy (and temozolomide in particular) showed inferior OS compared to radiotherapy in astrocytomas (median 6.1/12.1 years; p = 0.03) and oligodendrogliomas (median 13.2/not reached (n.r.) years; p = 0.03). While radiochemotherapy improved TTF in oligodendroglioma (median radiochemotherapy n.r./chemotherapy 3.8/radiotherapy 7.3 years; p < 0.001/ = 0.06; OS data immature) the effect, mainly in combination with temozolomide, was weaker in astrocytomas (median radiochemotherapy 6.7/chemotherapy 2.3/radiotherapy 2.0 years; p < 0.001/ = 0.11) and did not translate to improved OS (median 8.4 years).

Conclusion

This is one of the largest retrospective, real-life datasets reporting treatment and outcome in low-grade gliomas incorporating molecular markers. Current histologic grading features remain prognostic in astrocytomas while being insignificant in oligodendroglioma with interfering treatment effects. Chemotherapy (temozolomide) was less effective than radiotherapy in both astrocytomas and oligodendrogliomas while radiochemotherapy showed the highest TTF in oligodendrogliomas.
HER2 copy number as predictor of disease-free survival in HER2-positive resectable gastric adenocarcinoma
Authors: Liu Zimin , Shi Mingpeng , Li Xiaoxiao , Song Shanai , Liu Ning , Du Haiwei , Ye Junyi , Li Haiyan , Zhang Zhou , Zhang Lu
Published: February 2021

Purpose

The identification of HER2 overexpression in a subset of gastric adenocarcinoma (GA) patients represents a significant step forward in unveiling the molecular complexity of this disease. The predictive and prognostic value of HER2 amplification in advanced HER2 inhibitor-treated GA patients has been investigated. However, its predictive value in resectable patients remains elusive.

Methods

We enrolled 98 treatment-naïve resectable Chinese GA patients with HER2 overexpression assessed using IHC. Capture-based targeted sequencing using a panel consisting of 41 gastrointestinal cancer-related genes was performed on tumor tissues. Furthermore, we also investigated the correlation between HER2 copy number (CN) and survival outcomes.

Results

Of the 98 HER2-overexpressed patients, 90 had HER2 CN amplification assessed using next-generation sequencing, achieving 92% concordance. The most commonly seen concurrent mutations were occurring in TP53, EGFR and PIK3CA. We found HER2 CN as a continuous variable was an independent predictor associated with DFS (p = 0.029). Our study revealed HER2 CN-high patients showed a trend of intestinal-type GA predominant (p = 0.075) and older age (p = 0.07). The median HER2 CN was 15.34, which was used to divide the cohort into CN-high and CN-low groups. Patients with high HER2 CN had a significantly shorter DFS than patients with low HER2 CN (p = 0.002). Furthermore, HER2 CN as a categorical variable was also an independent predictor associated with DFS in patients.

Conclusion

We elucidated the mutation spectrum of HER2-positive resectable Chinese GA patients and the association between HER2 CN and DFS. Our work revealed HER2 CN as an independent risk factor predicted unfavorable prognosis in HER2-positive GA patients and allowed us to further stratify HER2-positive resectable GA patients for disease management.
Treatment stage migration and treatment sequences in patients with hepatocellular carcinoma: drawbacks and opportunities
Authors: Wehling Cyrill , Dill Michael T. , Olkus Alexander , Springfeld Christoph , Chang De-Hua , Naumann Patrick , Longerich Thomas , Kratochwil Clemens , Mehrabi Arianeb , Merle Uta , Pfeiffenberger Jan , Rupp Christian , Weiss Karl Heinz , Mieth Markus
Published: February 2021

Purpose

This retrospective analysis focuses on treatment stage migration in patients with hepatocellular carcinoma (HCC) to identify successful treatment sequences in a large cohort of real-world patients.

Methods

1369 HCC patients referred from January 1993 to January 2020 to the tertiary center of the Heidelberg University Hospital, Germany were analyzed for initial and subsequent treatment patterns, and overall survival.

Results

The most common initial treatment was transarterial chemoembolization (TACE, n = 455, 39.3%) followed by hepatic resection (n = 303, 26.1%) and systemic therapy (n = 200, 17.3%), whereas the most common 2nd treatment modality was liver transplantation (n = 215, 33.2%) followed by systemic therapy (n = 177, 27.3%) and TACE (n = 85, 13.1%). Kaplan–Meier analysis revealed by far the best prognosis for liver transplantation recipients (median overall survival not reached), followed by patients with hepatic resection (11.1 years). Patients receiving systemic therapy as their first treatment had the shortest median overall survival (1.7 years; P < 0.0001). When three or more treatment sequences preceded liver transplantation, patients had a significant shorter median overall survival (1st seq.: not reached; 2nd seq.: 12.4 years; 3rd seq.: 11.1 years; beyond 3 sequences: 5.5 years; P = 0.01).

Conclusion

TACE was the most common initial intervention, whereas liver transplantation was the most frequent 2nd treatment. While liver transplantation and hepatic resection were associated with the best median overall survival, the timing of liver transplantation within the treatment sequence strongly affected median survival.
Complement activation in children with Streptococcus pneumoniae associated hemolytic uremic syndrome
Authors: Holle Johannes , Habbig Sandra , Gratopp Alexander , Mauritsch Anna , Müller Dominik , Thumfart Julia
Published: February 2021

Background

Hemolytic uremic syndrome caused by invasive pneumococcal disease (P-HUS) is rare in children and adolescents, but accompanied by high mortality in the acute phase and complicated by long-term renal sequelae. Abnormalities in the alternative complement pathway may additionally be contributing to the course of the disease but also to putative treatment options.

Methods

Retrospective study to assess clinical course and laboratory data of the acute phase and outcome of children with P-HUS.

Results

We report on seven children (median age 12 months, range 3–28 months) diagnosed with P-HUS. Primary organ manifestation was meningitis in four and pneumonia in three patients. All patients required dialysis which could be discontinued in five of them after a median of 25 days. In two patients, broad functional and genetic complement analysis was performed and revealed alternative pathway activation and risk haplotypes in both. Three patients were treated with the complement C5 inhibitor eculizumab. During a median follow-up time of 11.3 years, one patient died due to infectious complications after transplantation. Two patients showed no signs of renal sequelae.

Conclusions

Although pathophysiology in P-HUS remains as yet incompletely understood, disordered complement regulation seems to provide a clue to additional insights for pathology, diagnosis, and even targeted treatment.
Subjective resource value affects aggressive behavior independently of resource-holding-potential and color morphs in male common wall lizard
Authors: Sacchi Roberto , Coladonato Alan J. , Battaiola Mara , Pasquariello Carlotta , Buratti Simone , Matellini Cristian , Mangiacotti Marco , Scali Stefano , Zuffi Marco A. L.
Published: February 2021

Game theory models predict the outcome of a dyadic contest to depend on opponents’ asymmetries in three main traits: resource-holding potential (RHP), resource value (RV) and aggressiveness. Using male common wall lizards Podarcis muralis, a polymorphic species showing three discrete morphs (white, yellow, and red), we investigated how the aggressive behavior varies according to a change in subjective RV and color morphs, while controlling for the asymmetry in RHP (using mirrors). By comparing the aggression of the same individual towards its mirror image in two different arenas (familiar = high subjective RV; novel = low subjective RV), we showed that lizard aggressive behavior was more intense and prolonged in the familiar arena than in the new one, thus supporting the occurrence of a direct relationship between motivation and aggression in this species. We also found the overall aggressiveness to differ from individual to individual, supporting the general hypothesis that aggressiveness is a trait associated with personality. By contrast, no effect of morphs was detected, ruling out the occurrence of morph specific variation in the aggressiveness. Our results highlight that an individual’s motivation and personality might be as important as RHP and RV in the resolution of animal contests.
Repatterning of the inflorescence meristem in Gerbera hybrida after wounding
Authors: Zhang Teng , Wang Feng , Elomaa Paula
Published: February 2021

The Asteraceae plant family is characterized by inflorescences, called flower heads or capitula that may combine hundreds of individual florets into a single flower-like structure. The florets are arranged in a regular phyllotactic pattern with Fibonacci numbers of left- and right-winding spirals. Such a pattern may be disrupted due to physical constraints or by wounding occurring during the early meristem development. Recovery from wounding re-establishes patterning although the mechanisms have remained elusive. In this study, we applied Gerbera hybrida as a model system and established methods to conduct wounding experiments either with syringe needles or using laser ablation combined with live imaging of head meristems. By revisiting the historical experiments in sunflower, we conducted wounding to transgenic auxin reporter lines of gerbera and followed the recovery of cellular growth and meristem patterning. We show that wounding disrupted the expression of the gerbera CLAVATA3 (GhCLV3) gene that marks the undifferentiated meristematic region and led to de novo re-initiation of patterning at the wound margin. During the recovery growth, three to five layers of elongated cells showing periclinal cell division planes and lacking auxin signal were formed at the wound rim. DR5 auxin signal was shown to localize and form regularly spaced maxima in a distance from the wound rim. Consequently, spiral pattern of contact parastichies was re-established by stacking of new auxin maxima on top of the previous ones. The developed methods facilitate future studies on understanding the molecular mechanisms of de novo patterning of meristems.
Time-Dependent Wave Equations on Graded Groups
Authors: Ruzhansky Michael , Taranto Chiara Alba
Published: February 2021

In this paper we consider the wave equations for hypoelliptic homogeneous left-invariant operators on graded Lie groups with time-dependent Hölder (or more regular) non-negative propagation speeds. The examples are the time-dependent wave equation for the sub-Laplacian on the Heisenberg group or on general stratified Lie groups, or $p$
p
-evolution equations for higher order operators on ${{\mathbb{R}}}^{n}$

R
n

or on groups, already in all these cases our results being new. We establish sharp well-posedness results in the spirit of the classical result by Colombini, De Giorgi and Spagnolo. In particular, we describe an interesting local loss of regularity phenomenon depending on the step of the group (for stratified groups) and on the order of the considered operator.
Nudges in SRI: The Power of the Default Option
Authors: Gajewski Jean-Francois , Heimann Marco , Meunier Luc
Published: February 2021

We introduce nudges in order to incite investors to choose Socially Responsible Investment (SRI) funds instead of traditional funds. We have set up two online experiments with a total of 713 US retail investors, using three types of nudges to elicit their effects on investors’ SRI investments level: making SRI the default investment, introducing a SRI explanation message, and priming ethical values by displaying shocking images. Making SRI the default option is the most efficient nudge to influence investors towards SRI. Its effect is twofold. First, around 50% of investors do not opt-out of the default allocation. Second, even investors who opt-out of the default allocation invest more in SRI than those in the control group, an effect that appears driven by anchoring. Although investors subjected to both priming and message content marginally increase their SRI investment, priming or message content in isolation appears to have a non-significant influence. For choice architects who want to steer retail investors towards SRI funds, making them the default option appears to be the most powerful nudge.
An in-depth investigation of critical stretch based failure criterion in ordinary state-based peridynamics
Authors: Karpenko Olena , Oterkus Selda , Oterkus Erkan
Published: February 2021

This study presents an in-depth investigation of the critical stretch based failure criterion in ordinary state-based peridynamics for both static and dynamic conditions. Seven different cases are investigated to determine the effect of the failure parameter on peridynamic forces between material points and dilatation. Based on crack opening displacement (COD) results from both peridynamics and finite element analysis, it was found that one of the seven cases provides the best agreement between the two approaches. This particular case is further investigated by considering the influence of the discretisation and the horizon sizes on COD and crack propagation speeds. Moreover, PD predictions of COD for PMMA material is analysed with the theory of dynamic fracture mechanics and compared with the fracture experiments. It is shown that the peridynamic model can correctly model, simulate and predict the behaviour of the crack under different loading conditions. Furthermore, the presented PD models capture accurate fracture phenomena, specifically the crack path, branching angles and crack propagation speeds, which are in good agreement with experimental results.
The J-area integral applied in peridynamics
Authors: Stenström Christer , Eriksson Kjell
Published: February 2021

TheJ-integral is in its original formulation expressed as a contour integral. The contour formulation was, however, found cumbersome early on to apply in the finite element analysis, for which method the more directly applicableJ-area integral formulation was later developed. In a previous study, we expressed theJ-contour integral as a function of displacements only, to make the integral directly applicable in peridynamics (Stenström and Eriksson in Int J Fract 216:173–183, 2019). In this article we extend the work to include theJ-area integral by deriving it as a function of displacements only, to obtain the alternative method of calculating theJ-integral in peridynamics as well. The properties of the area formulation are then compared with those of the contour formulation, using an exact analytical solution for an infinite plate with a central crack in Mode I loading. The results show that theJ-area integral is less sensitive to local disturbances compared to the contour counterpart. However, peridynamic implementation is straightforward and of similar scope for both formulations. In addition, discretization, effects of boundaries, both crack surfaces and other boundaries, and integration contour corners in peridynamics are considered.
Task-Space Admittance Controller with Adaptive Inertia Matrix Conditioning
Authors: Fonseca Mariana de Paula Assis , Adorno Bruno Vilhena , Fraisse Philippe
Published: February 2021

Whenrobots physically interact with the environment, compliant behaviors should be imposed to prevent damages to all entities involved in the interaction. Moreover, during physical interactions, appropriate pose controllers are usually based on the robot dynamics, in which the ill-conditioning of the joint-space inertia matrix may lead to poor performance or even instability. When the control is not precise, large interaction forces may appear due to disturbed end-effector poses, resulting in unsafe interactions. To overcome these problems, we propose a task-space admittance controller in which the inertia matrix conditioning is adapted online. To this end, the control architecture consists of an admittance controller in the outer loop, which changes the reference trajectory to the robot end-effector to achieve a desired compliant behavior; and an adaptive inertia matrix conditioning controller in the inner loop to track this trajectory and improve the closed-loop performance. We evaluated the proposed architecture on a KUKA LWR4+ robot and compared it, via rigorous statistical analyses, to an architecture in which the proposed inner motion controller was replaced by two widely used ones. The admittance controller with adaptive inertia conditioning presents better performance than with a controller based on the inverse dynamics with feedback linearization, and similar results when compared to the PID controller with gravity compensation in the inner loop.
Short Strong Hydrogen Bonds can Hinder Complex Formation: A Stability and Structure Study of Copper(II) Alkyl-N-iminodiacetic Acid Complexes in Aqueous Systems and Solid State
Authors: Häggman Leif , Cassel Anders , Persson Ingmar
Published: February 2021

In the present study the solution and coordination chemistry of copper(II)–alkyl-N-iminodiacetate systems are studied in aqueous solution by potentiometry, using ion selective copper and pH electrodes, EXAFS (extended X-ray absorption fine structure) and dye probe molecular absorption spectrophotometry. Alkyl-N-iminodiacetates with varying alkyl chain length, methyl (CH3–), n-hexyl (C6H13–), n-dodecyl (C12H25–) and n-octadecyl (C18H37–) were used to tune the amphiphilic properties of the ligands. The polar head groups have both oxygen (hard Lewis base) and nitrogen donor (border-line Lewis base) atoms. This means that metal ions with different bonding characteristics may bind these ligands differently. Furthermore, the chelating properties of the polar head group may be regulated by pH as the acid–base properties of the imine and carboxylic acid groups are different. Copper(II) forms two stable complexes with alkyl-N-iminodiacetates with short alkyl chains, present as monomers in aqueous solution, log10β1 = 11.10(2), log10β2 = 19.5(2) for methyl-N-iminodiacetate, and log10β1 = 12.22(4), log10β2 = 21.9(2) for n-hexyl-N-iminodiacetate. n-Octadecyl-N-iminodiacetic acid, present as large aggregates in acidic aqueous solution, has short strong hydrogen bonds between carboxylic acid and carboxylate groups in the surface of the aggregates, which hinder complex formation at pH values below 4, obstructs it in the pH region 4–7, while the complex formation behaves as for short-chained alkyl-N-iminodiacetates at pH > 7. The structure around copper in copper(II)–alkyl-N-iminodiacetate complexes in aqueous solution and solid state formed at different pH values and copper(II):alkyl-N-iminodiacetate ratios has been determined by EXAFS. The coordination chemistry of copper(II) shows four strong bonds in the equatorial plane, and two different Cu–O/N bond distances, ca. 0.2 Å apart, in the axial positions of a non-centrosymmetric tetragonally elongated octahedron.
The effects of current unsatisfactory performance and evaluative approach on improvement expectancy and commitment to improvement
Authors: Abdulla Adam , Woods Ruth
Published: February 2021

This study investigated the effects of current unsatisfactory performance (CUP) on improvement expectancy (IE) and commitment to improvement (CTI). 118 high school students were randomly assigned to consider either current satisfactory performance (CSP) or CUP. In addition, students within each group were randomly assigned to one of two evaluative approaches: (1) dichotomous present-focused evaluation (“Are you succeeding in this area? Or not?”), or (2) historical success scaling (“What is the highest level of success that you have reached in this area?”). It was hypothesised that (relative to CSP) CUP has a negative effect on improvement expectancy (IE). This hypothesis was supported. In addition, the data were consistent with an inconsistent mediation hypothesis according to which CUP has a positive direct effect on CTI but a negative indirect effect through reduced IE. The indirect effect of CUP on CTI was expected to be less negative amongst students engaging in historical success scaling than amongst students engaging in dichotomous present-focused evaluation. Although this was indeed the case, a test of moderated mediation indicated that the conditional indirect effects did not differ statistically. The study helps to illuminate the conflicting effects of CUP on CTI. Findings also have important implications for cognitive-behavioural and solution-focused approaches, both of which champion “scaling.”
Triggers for the Impoverishment of the Macroinvertebrate Communities in the Human-Impacted Rivers of Two Central European Ecoregions
Authors: Halabowski Dariusz , Lewin Iga
Published: February 2021

Human activity triggers negative alternations in river habitats, including changes to the physical and chemical parameters of the water, its hydromorphological features and the introduction and spread of invasive alien species. These modifications are expected to be intensified by climate change. Eight rivers in one of the most urbanised and industrialised regions in Europe, i.e. the Upper Silesian Coal Basin, were surveyed in order to explain the impact of anthropopressure on the distribution of macroinvertebrates. Conductivity, altitude, hydromorphological transformations, hardness, the organic matter content and certain fractions of benthic sediments significantly affect (p < 0.01) the occurrence of macroinvertebrates in Central European rivers. Our results proved that the hydromorphological transformation of watercourses, which is expressed by the relevant indices, is one of the most predictive factors that contribute to the distribution of macroinvertebrates. Anthropogenic inland waters that have been salinised by the discharge of hard coal mine waters create new habitats for brackish and marine species that replace native freshwater species. An increase in salinity causes an impoverishment of macroinvertebrate biodiversity therefore all possible actions should be taken to reduce the anthropogenic salinity of inland waters. Secondary saline rivers may prove to be prescient for climate-induced changes to river macroinvertebrates.
Do fair value measurements affect accounting-based earnings quality? A literature review with a focus on corporate governance as moderator
Authors: Thesing Johannes , Velte Patrick
Published: February 2021

This structured literature review of 48 archival-based studies investigates the influence of fair value measurements on earnings quality and stresses the moderating impact of corporate governance. We focus on accounting-based earnings quality measures that have several advantages for investigating agency-related earnings management behavior compared to market-based measures (e.g. value relevance studies). Fair value measurements are not restricted to specific industries, periods, circumstances, or items in our sample. Based on the applied earnings quality measure, the reviewed articles are structured into five categories: (1) earnings persistence and predictive ability, (2) discretionary accruals, (3) target beating and properties of analysts’ forecasts, (4) earnings variability, and (5) other earnings quality measures. We indicate three key findings: first, fair value measurements show mixed earnings quality; second, lower-level fair value measurements decrease earnings quality; and third, corporate governance measures enhance earnings quality. After that, we deduce six research questions for future research. We show possible extensions to previous research designs in methodology and settings. Future research should also focus on corporate governance variables to a greater extent, especially compensation and board structures. Thereby, we suggest extending the neoclassical view with behavioral aspects.
Analysis of protein-network formation of different vegetable proteins during emulsification to produce solid fat substitutes
Authors: Baune Marie-Christin , Schroeder Sarah , Witte Franziska , Heinz Volker , Bindrich Ute , Weiss Jochen , Terjung Nino
Published: February 2021

Plant-based emulsion gels can be used as solid animal fat substitutes for vegan sausages. For this reason, commercially available protein isolates with different amino acid profiles from pea, soy and potato (Pea-1, Pea-2, Soy, Potato) have been tested for their ability to form shape stable emulsions gels at neutral pH and upon heating to 72 °C. In order to obtain emulsion gels that are as solid as possible, the protein concentrations in the continuous phase (CPC, 8.0–11.5% (w/w)) and the oil mass fractions (65–80%) were varied. For leguminous proteins, a positive correlation of both parameters on emulsion rigidity was shown, indicating that both, interfacial and protein–protein interactions, are involved in structure reinforcement. Firmness increased with increasing content in cysteine (Pea-1 < Pea-2 < Soy) and the interactions were of electrostatic, hydrophobic and hydrophilic nature. Potato emulsion rigidity was independent of CPC and oil content. The emulsions showed a much higher degree in crosslinking, and very low charge density. Temperature-sweep analysis and CLSM revealed that Potato protein gelled as consequence to low temperature stability. Hence, the structure reinforcement in Potato emulsions mainly contributed to the protein network, with 70% oil and CPC 11.5% forming a hybrid gel with highest firmness. However, gelling of Potato protein also resulted in interfacial adsorption of protein aggregates and reduced interfacial stability with increasing CPC. This was demonstrated in the amount of extractable fat which was 2.0 and 0.6% for Pea-1 and 2 emulsions, 6.4% for Soy and 34.4% of total fat for Potato emulsions.
Decrease of dipeptidyl peptidase 4 activity is associated with weight loss after bariatric surgery
Authors: Herz Carsten T. , Brix Johanna M. , Ludvik Bernhard , Schernthaner Guntram , Schernthaner Gerit-Holger
Published: February 2021

Purpose

Dipeptidyl peptidase 4 (DPP4) is expressed and secreted by adipocytes. DPP4 induces insulin resistance independently of its effect on glucagon-like peptide 1, thus it is conceivable that DPP4 directly contributes to metabolic dysfunction in patients with morbid obesity. The aim of this study was to investigate the impact of weight loss induced by bariatric surgery on DPP4 activity, and whether these changes are associated with improvements in markers of metabolic dysfunction and fatty liver disease.

Materials and Methods

We included 68 non-diabetic patients who underwent bariatric surgery. Serum DPP4 activity was measured using a fluorogenic substrate before and after surgery.

Results

Results: After a median follow-up period of 12 (IQR 11-17) months, median serum DPP4 activity decreased from 230 (IQR: 194-273) to 193 (164-252) pmol/min (p=0.012). The decrease in DPP4 activity was significantly correlated with decreases in BMI, improved cholesterol levels, reduced hepatic injury markers as well as improved post-prandial insulin sensitivity. After multivariable adjustment, ΔDPP4 activity remained significantly associated with Δcholesterol (beta=0.341, p=0.025), ΔLDL cholesterol (beta=0.350, p=0.019), Δgamma-glutamyltransferase (beta=0.323, p=0.040) and ΔMatsuda index (beta=-0.386, p=0.045).

Conclusion

We demonstrated that weight loss induced by bariatric surgery results in decreased circulating DPP4 activity beyond the initial phase of weight loss. The associations between decreased DPP4 activity and improved cholesterol levels as well as hepatic injury markers point towards pleiotropic effects of DPP4 beyond glucose metabolism which warrant further investigation.
Primary Progressive Aphasia: Toward a Pathophysiological Synthesis
Authors: Ruksenaite Justina , Volkmer Anna , Jiang Jessica , Johnson Jeremy CS , Marshall Charles R , Warren Jason D , Hardy Chris JD
Published: February 2021

Purpose of Review

The term primary progressive aphasia (PPA) refers to a diverse group of dementias that present with prominent and early problems with speech and language. They present considerable challenges to clinicians and researchers.

Recent Findings

Here, we review critical issues around diagnosis of the three major PPA variants (semantic variant PPA, nonfluent/agrammatic variant PPA, logopenic variant PPA), as well as considering ‘fragmentary’ syndromes. We next consider issues around assessing disease stage, before discussing physiological phenotyping of proteinopathies across the PPA spectrum. We also review evidence for core central auditory impairments in PPA, outline critical challenges associated with treatment, discuss pathophysiological features of each major PPA variant, and conclude with thoughts on key challenges that remain to be addressed.

New findings elucidating the pathophysiology of PPA represent a major step forward in our understanding of these diseases, with implications for diagnosis, care, management, and therapies.
Geochemical analysis for evaluating the paleoweathering, paleoclimate, and depositional environments of the siliciclastic Miocene-Pliocene sequence at Al-Rehaili area, Northern Jeddah, Saudi Arabia
Authors: Alqahtani Faisal , Khalil Mohammed
Published: February 2021

Geochemical data and their various approaches are useful to evaluate the climatic control on the depositional environments. This study aims to evaluate the paleoweathering and plaeoclimate condition that have controls on the depositional environments of the Miocene to Pliocene siliciclastic sequence at Al-Rehaili area, north of Jeddah. To achieve this aim, selected sandstone samples were geochemically (major and trace elements analysis) and petrographically examined. The results of these analyses reveal that the examined sandstones were deposited in non-marine (fluvial/alluvial-lacustrine) environments and suffered from weak to intermediate chemical weathering and intense physical induration under semi-arid to semi-humid climatic conditions.
The molecular vista: current perspectives on molecules and life in the twentieth century
Authors: Grote Mathias , Onaga Lisa , Creager Angela N. H. , de Chadarevian Soraya , Liu Daniel , Surita Gina , Tracy Sarah E.
Published: February 2021

This essay considers how scholarly approaches to the development of molecular biology have too often narrowed the historical aperture to genes, overlooking the ways in which other objects and processes contributed to the molecularization of life. From structural and dynamic studies of biomolecules to cellular membranes and organelles to metabolism and nutrition, new work by historians, philosophers, and STS scholars of the life sciences has revitalized older issues, such as the relationship of life to matter, or of physicochemical inquiries to biology. This scholarship points to a novel molecular vista that opens up a pluralist view of molecularizations in the twentieth century and considers their relevance to current science.
Money management and entrepreneurial training in microfinance: impact on beneficiaries and institutions
Authors: Dalla Pellegrina Lucia , Di Maio Giorgio , Landoni Paolo , Rusinà Emanuele
Published: February 2021

This study uses a randomized control trial to evaluate the outcome of integrating money management and entrepreneurial training into a microcredit program in India. We find positive and significant effects on clients’ financial management skills and entrepreneurship abilities, particularly for clients with higher human capital, or more diligent, or having an entrepreneurial idea, and an increase in initiative and self-confidence. Effects appear stronger for clients obliged to attend the training course or more interested in attending it. By considering missed or delayed repayments reduction we assess the benefits of the training provided and of extending it for the institution.
Enhancement and Standardization of a Universal Social-Emotional Health Measure for Students’ Psychological Strengths
Authors: Furlong Michael J. , Dowdy Erin , Nylund-Gibson Karen , Wagle Rhea , Carter Delwin , Hinton Tameisha
Published: February 2021

Robust evidence links students’ positive mental health with academic achievement and provides a compelling rationale for developing and refining strength-based assessments. The Social Emotional Health Survey–Secondary (SEHS-S) assesses adolescents’ social and emotional skills and positive psychological dispositions. Previous studies provide reliability and validity evidence; nonetheless, there is a need for continued refinement and validation across diverse groups. The current study revised and standardized the updated SEHS-S-2020 to validate further its use in secondary schools (Grades 9–12) with a large, diverse adolescent sample. Study participants included 72,740 from 113 California schools (structural validation sample), 10,757 students from 15 randomly selected California schools (criterion validation sample), and 707 students from four additional California schools (test-retest sample). Data analyses examined structural validity, measurement invariance, criterion validity, internal consistency, and response stability. Results supported the SEHS-S-2020 validity across diverse groups of youth in various contexts. The discussion focuses on implications for assessing students’ psychosocial assets and universal school-based screening.