bluuebunny/crossref_metadata_2025_split huggingface dataset:
Promotion of 11/9‐helical folding in α/β‐peptides containing β2‐homoalanine residue
Authors: Yoon Hyerim , Lee Jaeyeon , Kang Philjae , Choi Soo Hyuk 
Published: September 2021

AbstractThe 11/9‐helix is one of nontraditional helices available to α/β‐peptides with alternating residue types. Several β‐amino acid residues are known to promote 11/9‐helical folding with two types of intramolecular hydrogen bonds. Both β2‐amino acids and β3‐amino acids are common acyclic β‐amino acids that can be regarded as homologs of α‐amino acids with the same side chain group. However, β2‐amimo acids have not been widely used as much as β3‐amino acids partly because β2‐residue is believed to be not as strong as β3‐residue in promoting a distinct conformation. Here we report 11/9‐helical folding of α/β‐peptides that consist of L‐α‐alanine and (S)‐β2‐homoalanine with residue alternation. In addition, circular dichroism study reveals that β2‐homoalanine promotes 11/9‐helical folding more strongly than β3‐homoalanine in polar protic solvent conditions.
Laryngeal sensation and its association with aspiration and cough in children with neurological impairment
Authors: Freitag Nadine , Tews Pia , Hübl Nicole , Krug Katrin , Kristin Julia , Distelmaier Felix , Schramm Dirk 
Published: September 2021

AbstractBackgroundAspirations are frequent in children with neurological impairment. They significantly increase the risk for acute and chronic respiratory insufficiencies leading to high morbidity and mortality. Laryngeal sensation deficits have been linked to aspirations in adults and are a suspected cause for dysphagia in children. In a similar neurological circuit as swallowing, laryngeal receptors trigger coughing as a protective airway reflex. The aim of this study was to examine the association between impaired laryngeal sensation (ILS), aspiration, and coughing in neurologically impaired children.Design and MethodsIn a retrospective study, 110 children with suspected dysphagia underwent a clinical evaluation of swallowing and a flexible endoscopic evaluation of swallowing (FEES) between 2013 and 2019 in the children's university clinic Düsseldorf were analyzed. Laryngeal sensation was tested by the endoscopic touch method. Associations were computed using χ2‐test.ResultsFifty‐four patients (49.1%) had a neurological impairment, 56 patients (50.9%) had no or other comorbidities and served as a control cohort. Children with neurological impairment suffered from ILS significantly more often than children with no or other comorbidities (χ²(1) = 4.63, p = .031). ILS was associated with all other FEES variables but did not correlate with coughing. The symptom coughing correlated with aspiration in the group of neurologically impaired children and in children ILS.ConclusionILS is a potential cause of aspirations in children with neurological impairment. Physicians need to pay special attention to the occurrence of coughing in children with neurological impairment and/or ILS since it signals aspirations that took place.
Semi‐parametric accelerated failure‐time model: A useful alternative to the proportional‐hazards model in cancer clinical trials
Authors: Burzykowski Tomasz 
Published: September 2021

AbstractThe accelerated failure‐time (AFT) model has been long recognized as a useful alternative to the proportional‐hazards (PH) model. Semi‐parametric AFT model has been known since 1981. Its use has been hampered by the difficulty in solving the estimating equations for the model's coefficients. In recent years, however, important developments have taken place regarding the methods of solving the equations. In this article, we briefly review the developments, focusing mainly on rank‐based estimation. We conduct a simulation study that directly focuses on the applicability of the model in the context of (cancer) clinical trials. We also investigate the robustness of the AFT model to the omission of covariates. Finally, we conduct a meta‐analysis of multiple clinical trials in gastric cancer to illustrate the benefits of the use of the model in practice.
Biochar restructures plant–soil–microbe relationships in a woody cropping system
Authors: Nash Jake A. , Miesel Jessica R. , Bonito Gregory M. , Sakalidis Monique L. , Ren Han , Warnock Daniel , Tiemann Lisa K. 
Published: September 2021

AbstractBiochars are porous charcoal‐like materials that can enhance soil health and plant growth, but their use has not been adequately evaluated in woody cropping systems. To fill this knowledge gap, we investigated the effects of two slow pyrolysis pine biochars on plant performance, soil physicochemical properties, extracellular enzyme activities, and root‐associated fungal community composition in an experimental Christmas tree plantation over 3 yr. Both biochars stimulated the activities of five extracellular enzyme activities between 67 and 446%, but appeared to reduce N availability. Structural equation modelling identified increased soil moisture as a potential mechanism of biochar's effects on all measured enzyme activities, whereas increased dissolved organic C was a possible mechanism of biochar's effect on N and P targeting enzymes. This finding suggests that biochar‐induced increases to dissolved organic C have a specific effect on nutrient targeting enzymes. Biochar was found to negatively impact tree growth and survival, but impacts varied between tree species and biochar type. High‐throughput sequencing showed that biochar decreased the diversity of root‐associated fungal communities, with the ectendomycorrhizal speciesWilcoxina mikolaebecoming hyper‐dominant on balsam fir in response to one of the biochars. Changes to root‐associated fungal communities may have been partially responsible for negative effects on conifer performance. Although our study identified negative effects of biochar on plant performance and fungal diversity, we also found widespread changes to soil chemistry and microbial function that might be leveraged in systems with more acidic soils or different crops to increase plant performance.
Size‐Controlled Facile Synthesis of Silver Nanoparticles by Chemical Reduction Method and Analysis of Their Antibacterial Performance
Authors: Halder Sanjoy , Ahmed Aninda N. , Gafur Md. A. , Seong Gimyeong , Hossain Muhammad Z. 
Published: September 2021

AbstractThis article aimed at the size‐controlled one‐pot facile synthesis of silver nanoparticles (AgNPs) by chemical reduction method and their antibacterial response against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. AgNPs coated with and without trisodium citrate (TSC) were synthesized using silver nitrate as a precursor and hydrazine as a reducing agent. Spherical AgNPs (average size 35 nm) formation, capping agents attachment, and product purity was confirmed by ultraviolet‐visible (UV–vis) spectroscopy, X‐ray diffraction (XRD), field emission scanning microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), the thermogravimetric analysis (TGA), and energy‐dispersive X‐ray (EDX) spectroscopy. Exposing the synthesized TSC uncoated and coated AgNPs to Gram‐negative E. coli bacteria at a concentration of 50 mg L−1, the zone inhibition was found to be 5 mm and 6 mm, respectively. Again, TSC coated AgNPs exhibited a notable zone inhibition of 8 mm to Gram‐positive S. aureus. These results suggest that chemically synthesized TSC coated AgNPs could be used as an antibiotic against S. aureus and E. coli, which is very inspiring.
Graphene‐Based Nanomaterials for Biomedical, Catalytic, and Energy Applications
Authors: Basak Soumyadeep , Packirisamy Gopinath 
Published: September 2021

AbstractNanotechnology has provided us with unimaginable possibilities in addressing worldly challenges. Since its discovery in 2004, Graphene has been considered a “Holy Grail” of nanomaterials for its unprecedented applicability in different fields, including biomedical, energy harvest and storage, sensing applications. Throughout the world, tremendous waves of research have been going on to exploit graphene‘s unique thermal, mechanical, electrical, catalytic, and biological properties. Besides, efficient and tunable techniques of graphene‘s bulk manufacturing have been under thorough investigation. This article reviews various recent studies on large‐scale graphene synthesis with tunable properties. Several different ways of graphene‘s use in various catalytic platforms are also reviewed. Furthermore, recent biomedical and energy (storage and harvest) applications of graphene, especially in microbial fuel cell technology, bio‐sensing, antimicrobial applications, have been discussed in this article.
Copper‐Catalyzed Decarboxylative Cycloaddition of Alkynyl Carboxylic Acids and Sodium Azide with Epoxides and Ethers
Authors: Beukeaw Danupat , Yotphan Sirilata 
Published: September 2021

AbstractCopper‐catalyzed decarboxylative cycloaddition of alkynyl carboxylic acids and sodium azide with structurally different epoxides and ethers has been reported for the regioselective synthesis of 1,4‐disubstituted‐1,2,3‐triazoles. These one‐pot transformations are likely to proceed through a mechanism that involves an in situ generated organic azide intermediate, a decarboxylative formation of copper‐alkyne component, and a ring closure to form triazole product. The present three‐component protocols offer several advantages including using economic, bench stable and safe azide source, simple and convenient experimental procedures, high product yields, excellent regioselectivity, wide substrate scope and good functional group tolerance, which could promote their potential synthetic applications in many related areas.
Transformations for climate change mitigation: A systematic review of terminology, concepts, and characteristics
Authors: Moore Brendan , Verfuerth Caroline , Minas Angela Mae , Tipping Christianne , Mander Sarah , Lorenzoni Irene , Hoolohan Claire , Jordan Andrew J. , Whitmarsh Lorraine 
Published: September 2021

AbstractDeep, broad, and rapid society‐wide changes are urgently required to limit global temperature rise in line with the goals of the Paris Agreement. Since 2005, academics and policy makers have increasingly referred to such changes as transformations. This recent uptake and rapid diffusion of transformation‐related concepts in research on climate change mitigation calls for a systematic and up‐to‐date analysis. In this article, we address this gap by undertaking a systematic review of articles that use transformation‐related terms in the social science literature on climate change mitigation. Drawing on a corpus of 198 articles identified from Scopus, we find a diverse, fragmented research field that strongly focuses on the national, city, and international levels, the energy sector, and high‐income countries. Although the use of transformation terminology has increased rapidly, there are few shared definitions, which arguably constitutes a serious challenge to scholarship and evidence‐based policy making. To facilitate a more cumulative and impactful approach to research, we propose transformational climate change mitigation as a new umbrella term for the varied mitigation‐related societal transformations required to meet the goals of the Paris Agreement. We conclude by identifying priorities for future research.This article is categorized under:
The Carbon Economy and Climate Mitigation > Benefits of Mitigation
P not PQ
Authors: Craig Nathaniel , Garcia Isabel Garcia , Koszegi Giacomo , McCune Amara 
Published: September 2021

Abstract
Parity solutions to the strong CP problem are a compelling alternative to approaches based on Peccei-Quinn symmetry, particularly given the expected violation of global symmetries in a theory of quantum gravity. The most natural of these solutions break parity at a low scale, giving rise to a host of experimentally accessible signals. We assess the status of the simplest parity-based solution in light of LHC data and flavor constraints, highlighting the prospects for near-future tests at colliders, tabletop experiments, and gravitational wave observatories. The origin of parity breaking and associated gravitational effects play crucial roles, providing new avenues for discovery through EDMs and gravity waves. These experimental opportunities underline the promise of generalized parity, rather than Peccei-Quinn symmetry, as a robust and testable solution to the strong CP problem.
Causality constraints in Quadratic Gravity
Authors: Edelstein José D. , Ghosh Rajes , Laddha Alok , Sarkar Sudipta 
Published: September 2021

Abstract
Classifying consistent effective field theories for the gravitational interaction has recently been the subject of intense research. Demanding the absence of causality violation in high energy graviton scattering processes has led to a hierarchy of constraints on higher derivative terms in the Lagrangian. Most of these constraints have relied on analysis that is performed in general relativistic backgrounds, as opposed to a generic solution to the equations of motion which are perturbed by higher curvature operators. Hence, these constraints are necessary but may not be sufficient to ensure that the theory is consistent. In this context, we explore the so-called CEMZ causality constraints on Quadratic Gravity in a space of shock wave solutions beyond GR. We show that the Shapiro time delay experienced by a graviton is polarization-independent and positive, regardless of the strength of the gravitational couplings. Our analysis shows that as far as the causality constraints are concerned, albeit inequivalent to General Relativity due to additional propagating modes, Quadratic Gravity is causal as per as the diagnostic proposed by CEMZ.
Sliding behaviour and surface quality after static air polishing of conventional and modern bracket materials
Authors: Hodecker Lutz , Bourauel Christoph , Braumann Bert , Kruse Teresa , Christ Hildegard , Scharf Sven 
Published: September 2021

Abstract
Objectives
As part of orthodontic treatment, air polishing is routinely used for professional tooth cleaning. Thus, we investigated the effects of static powder polishing on sliding behaviour and surface quality of three different bracket materials (polymer, ceramic, metal), including a 3D-printed bracket.

Methods
Two bracket types of each material group were polished with an air-polishing device using sodium bicarbonate. Exposure times were set at 10, 20, and 60 s; the application distance was 5 mm. The force loss due to sliding resistance was tested with an orthodontic measurement and simulation system (OMSS) using a 0.016 inch × 0.022 inch stainless steel archwire. Untreated brackets served as control. Polishing effects and slot precision were evaluated using an optical digital and scanning electron microscope.

Results
Sliding behaviour and slot precision differed significantly between and within the groups. Prior to polishing, polymer brackets showed the least force loss, ceramic brackets the highest. With progressive polishing time, the resistance increased significantly with titanium brackets (26 to 37%) and decreased significantly with steel brackets (36 to 25%). Polymer brackets showed the smallest changes in force loss with respect to polishing duration. Slot precision showed the largest differences between material groups and was primarily manufacturer-dependent with hardly any changes due to the polishing time.

Conclusion
Powder polishing can positively or negatively affect the sliding properties of the bracket–archwire complex but is more dependent on the bracket–archwire material combination (i.e., manufacture-dependent slot precision). For titanium brackets, resistance only increased after 60 s of polishing. For ceramic brackets, effective reduction was observed after 10 s of polishing. Polymer brackets, including the 3D-printed brackets, showed better sliding properties than ceramic or metal brackets even after polishing for 60 s. Removal of plaque and dental calculus should lead to a noticeable improvement of the sliding properties and outweighs structural defects that may develop.
Updated pathology reporting standards for bladder cancer: biopsies, transurethral resections and radical cystectomies
Authors: Compérat Eva , Oszwald André , Wasinger Gabriel , Hansel Donna E. , Montironi Rodolfo , van der Kwast Theodorus , Witjes Johannes A. , Amin Mahul B. 
Published: September 2021

Abstract
Aim
Optimal management of bladder cancer requires an accurate, standardised and timely pathological diagnosis, and close communication between surgeons and pathologists. Here, we provide an update on pathology reporting standards of transurethral resections of the bladder and cystectomies.

Methods
We reviewed recent literature, focusing on developments between 2013 and 2021.

Results
Published reporting standards developed by pathology organizations have improved diagnosis and treatment. Tumor sub-staging and subtyping has gained increased attention. Lymph nodes continue to be an area of debate, and their staging has seen minor modifications. Several tasks, particularly regarding specimen preparation (“grossing”), are not yet standardized and offer opportunity for improvement. Molecular classification is rapidly evolving, but currently has only limited impact on management.

Conclusion
Pathological reporting of bladder cancer is continuously evolving and remains challenging in some areas. This review provides an overview of recent major developments, with a particular focus on published reporting standards.
High varus stem alignment in short-stem total hip arthroplasty: a risk for reconstruction of femoro-acetabular offset, leg length discrepancy and stem undersizing?
Authors: Luger Matthias , Stiftinger Julian , Allerstorfer Jakob , Hochgatterer Rainer , Gotterbarm Tobias , Pisecky Lorenz 
Published: September 2021

Abstract
Purpose
Short stems are increasingly used in in total hip arthroplasty (THA) because of advantages in bone and soft tissue preservation and reconstruction of hip geometry. Short stems can be inserted in a more varus position compared to conventional straight stems. This poses the risk of final varus misplacement of the femoral component, which is not intended in all femoral short stems.

Methods
We wanted to evaluate the effect of a high varus stem positioning in MIS THA on hip offset, leg length and femoral canal fill index. A series of 1052 consecutive THAs with a singular cementless femoral short stem and press-fit cup was retrospectively screened for inclusion. One hundred six patients with unilateral THA and a contralateral healthy hip met the inclusion criteria. Measurements were carried out on preoperative and 3 months anterior–posterior postoperative radiographs. Patients were divided into Group A (varus stem alignment ≤ 3°) and Group B (varus stem alignment > 3°).

Results
Hip offset (HO) increased significantly in Group B by 4 mm (p = 0.013). No influence on leg length difference was detected in both groups. Preoperative CCD angle was significantly lower in Group B (p < 0.001). Canal Fill Indices (CFI) were significantly lower in Group B (CFI I: p < 0.001; CFI II p = 0.003; CF III p = 0.002).

Conclusion
High varus stem alignment > 3° leads to a statistically significant but minor increase in HO and poses the risk of stem undersizing. A preoperatively low genuine CCD angle pose a risk for varus stem positioning.
Pitfalls in Sample Preparation of Metalloproteins for Low-Temperature EPR: The Example of Alkaline Myoglobin
Authors: Serra Ilenia , García Rubio Inés , Van Doorslaer Sabine 
Published: September 2021

AbstractDue to fast relaxation processes of transition metal ions, electron paramagnetic resonance (EPR) spectroscopy of metalloproteins needs to be performed at cryogenic temperatures. To avoid damaging the biological system upon freezing, a cryoprotectant is generally added to the sample as a glassing agent. Even though cryoprotectants are expected to be inert substances, evidences in literature show their non-innocent role in altering the shape of EPR spectra of proteins and biological objects in general. In this work we conduct a systematic study on the impact of several experimental factors—such as buffer composition, choice of cryoprotectant, pH and temperature—on the EPR spectrum of myoglobin, taken as a reference system for being a well-characterized heme-containing protein. We focus on high-pH buffers to induce and investigate the alkaline transition of ferric myoglobin (pKa ~ 8.9). A combined approach of continuous-wave EPR and UV–visible absorption spectroscopy shows that using particular pairs of buffers and cryoprotectants determines a considerable pH variation in the sample and that this effect is enhanced at cryogenic temperature. In addition, phase memory times were measured to evaluate the efficiency of different cryoprotectants and compared with spectral linewidths in continuous-wave EPR. Our findings suggest that among the selected cryoprotectants ethylene glycol is rather effective, even more than the widely used glycerol, without having unwanted effects.
Insulin and the insulin receptor collaborate to promote human gastric cancer
Authors: Saisana Marina , Griffin S. Michael , May Felicity E. B. 
Published: September 2021

Abstract
Background
Gastric adenocarcinoma is common and consequent mortality high. Presentation and mortality are increased in obese individuals, many of whom have elevated circulating insulin concentrations. High plasma insulin concentrations may promote, and increase mortality from, gastric adenocarcinoma. Tumour promotion activities of insulin and its receptor are untested in gastric cancer cells.

Methods
Tumour gene amplification and expression were computed from sequencing and microarray data. Associations with patient survival were assessed. Insulin-dependent signal transduction, growth, apoptosis and anoikis were analysed in metastatic cells from gastric adenocarcinoma patients and in cell lines. Receptor involvement was tested by pharmacological inhibition and genetic knockdown. RNA was analysed by RT-PCR and proteins by western transfer and immunofluorescence.

Results
INSR expression was higher in tumour than in normal gastric tissue. High tumour expression was associated with worse patient survival. Insulin receptor was detected readily in metastatic gastric adenocarcinoma cells and cell lines. Isoforms B and A were expressed. Pharmacological inhibition prevented cell growth and division, and induced caspase-dependent cell death. Rare tumour INS expression indicated tumours would be responsive to pancreatic or therapeutic insulins. Insulin stimulated gastric adenocarcinoma cell PI3-kinase/Akt signal transduction, proliferation, and survival. Insulin receptor knockdown inhibited proliferation and induced programmed cell death. Type I IGF receptor knockdown did not induce cell death.

Conclusions
The insulin and IGF signal transduction pathway is dominant in gastric adenocarcinoma. Gastric adenocarcinoma cell survival depends upon insulin receptor. That insulin has direct cancer-promoting effects on tumour cells has implications for clinical management of obese and diabetic cancer patients.