bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D‐Printed Reinforcement Scaffolds with Targeted Biodegradation Properties for the Tissue Engineering of Articular Cartilage
Authors: Tosoratti Enrico , Fisch Philipp , Taylor Scott , Laurent‐Applegate Lee Ann , Zenobi‐Wong Marcy 
Published: October 2021

AbstractAchieving regeneration of articular cartilage is challenging due to the low healing capacity of the tissue. Appropriate selection of cell source, hydrogel, and scaffold materials are critical to obtain good integration and long‐term stability of implants in native tissues. Specifically, biomechanical stability and in vivo integration can be improved if the rate of degradation of the scaffold material matches the stiffening of the sample by extracellular matrix secretion of the encapsulated cells. To this end, a novel 3D‐printed lactide copolymer is presented as a reinforcement scaffold for an enzymatically crosslinked hyaluronic acid hydrogel. In this system, the biodegradable properties of the reinforced scaffold are matched to the matrix deposition of articular chondrocytes embedded in the hydrogel. The lactide reinforcement provides stability to the soft hydrogel in the early stages, allowing the composite to be directly implanted in vivo with no need for a preculture period. Compared to pure cellular hydrogels, maturation and matrix secretion remain unaffected by the reinforced scaffold. Furthermore, excellent biocompatibility and production of glycosaminoglycans and collagens are observed at all timepoints. Finally, in vivo subcutaneous implantation in nude mice shows cartilage‐like tissue maturation, indicating the possibility for the use of these composite materials in one‐step surgical procedures.
Deterministic Shallow Dopant Implantation in Silicon with Detection Confidence Upper‐Bound to 99.85% by Ion–Solid Interactions
Authors: Jakob Alexander M. , Robson Simon G. , Schmitt Vivien , Mourik Vincent , Posselt Matthias , Spemann Daniel , Johnson Brett C. , Firgau Hannes R. , Mayes Edwin , McCallum Jeffrey C. , Morello Andrea , Jamieson David N. 
Published: October 2021

AbstractSilicon chips containing arrays of single dopant atoms can be the material of choice for classical and quantum devices that exploit single donor spins. For example, group‐V donors implanted in isotopically purified 28Si crystals are attractive for large‐scale quantum computers. Useful attributes include long nuclear and electron spin lifetimes of 31P, hyperfine clock transitions in 209Bi or electrically controllable 123Sb nuclear spins. Promising architectures require the ability to fabricate arrays of individual near‐surface dopant atoms with high yield. Here, an on‐chip detector electrode system with 70 eV root‐mean‐square noise (≈20 electrons) is employed to demonstrate near‐room‐temperature implantation of single 14 keV 31P+ ions. The physics model for the ion–solid interaction shows an unprecedented upper‐bound single‐ion‐detection confidence of 99.85 ± 0.02% for near‐surface implants. As a result, the practical controlled silicon doping yield is limited by materials engineering factors including surface gate oxides in which detected ions may stop. For a device with 6 nm gate oxide and 14 keV 31P+ implants, a yield limit of 98.1% is demonstrated. Thinner gate oxides allow this limit to converge to the upper‐bound. Deterministic single‐ion implantation can therefore be a viable materials engineering strategy for scalable dopant architectures in silicon devices.
Rippling Ferroic Phase Transition and Domain Switching In 2D Materials
Authors: Yang Yang , Zong Hongxiang , Sun Jun , Ding Xiangdong 
Published: October 2021

AbstractRipples are a class of native structural defects widely existing in 2D materials. They originate from the out‐of‐plane flexibility of 2D materials introducing spatially evolving electronic structure and friction behavior. However, the effect of ripples on 2D ferroics has not been reported. Here a molecular dynamics study of the effect of ripples on the temperature‐induced ferroic phase transition and stress‐induced ferroic domain switching in ferroelastic‐ferroelectric monolayer GeSe is presented. Ripples stabilize the short‐range ferroic orders in the high‐temperature phase with stronger ferroicity and longer lifetime, thereby increasing the transition temperature upon cooling. In addition, ripples significantly affect the domain switching upon loading, changing it from a highly correlated process into a ripple‐driven localized one where ripples act as source of dynamical random stress. These results reveal the fundamental role of ripples on 2D ferroicity and provide theoretical guidance for ripple engineering of controlled phase transition and domain switching with potential applications in flexible 2D electronics.
A Morphologically Stable Li/Electrolyte Interface for All‐Solid‐State Batteries Enabled by 3D‐Micropatterned Garnet
Authors: Xu Rong , Liu Fang , Ye Yusheng , Chen Hao , Yang Rachel Rae , Ma Yinxing , Huang Wenxiao , Wan Jiayu , Cui Yi 
Published: October 2021

AbstractMorphological degradation at the Li/solid‐state electrolyte (SSE) interface is a prevalent issue causing performance fading of all‐solid‐state batteries (ASSBs). To maintain the interfacial integrity, most ASSBs are operated under low current density with considerable stack pressure, which significantly limits their widespread usage. Herein, a novel 3D‐micropatterned SSE (3D‐SSE) that can stabilize the morphology of the Li/SSE interface even under relatively high current density and limited stack pressure is reported. Under the pressure of 1.0 MPa, the Li symmetric cell using a garnet‐type 3D‐SSE fabricated by laser machining shows a high critical current density of 0.7 mA cm–2 and stable cycling over 500 h under 0.5 mA cm–2. This excellent performance is attributed to the reduced local current density and amplified mechanical stress at the Li/3D‐SSE interface. These two effects can benefit the flux balance between Li stripping and creep at the interface, thereby preventing interfacial degradation such as void formation and dendrite growth.
Utilizing the Built‐in Electric Field of p–n Junctions to Spatially Propel the Stepwise Polysulfide Conversion in Lithium–Sulfur Batteries
Authors: Li Hongtai , Chen Chi , Yan Yingying , Yan Tianran , Cheng Chen , Sun Dan , Zhang Liang 
Published: October 2021

AbstractIntegrating sulfur cathodes with effective catalysts to accelerate polysulfide conversion is a suitable way for overcoming the serious shuttling and sluggish conversion of polysulfides in lithium–sulfur batteries. However, because of the sharp differences in the redox reaction kinetics and complicated phase transformation of sulfur, a single‐component catalyst cannot consistently accelerate the entire redox process. Herein, hierarchical and defect‐rich Co3O4/TiO2 p–n junctions (p‐Co3O4/n‐TiO2‐HPs) are fabricated to implement the sequential catalysis of S8(solid) → Li2S4(liquid) → Li2S(solid). Co3O4 sheets physiochemically immobilize the pristine sulfur and ensure the rapid reduction of S8 to Li2S4, while TiO2 dots realize the effective precipitation of Li2S, bridged by the directional migration of polysulfides from p‐type Co3O4 to n‐type TiO2 attributed to the interfacial built‐in electric field. As a result, the sulfur cathode coupled with p‐Co3O4/n‐TiO2‐HPs delivers long‐term cycling stability with a low capacity decay of 0.07% per cycle after 500 cycles at 10 C. This study demonstrates the synergistic effect of the built‐in electric field and heterostructures in spatially enhancing the stepwise conversion of polysulfides, which provides novel insights into the interfacial architecture for rationally regulating the polysulfide redox reactions.
Probing Multicellular Tissue Fusion of Cocultured Spheroids—A 3D‐Bioassembly Model
Authors: Lindberg Gabriella C. J. , Cui Xiaolin , Durham Mitchell , Veenendaal Laura , Schon Benjamin S. , Hooper Gary J. , Lim Khoon S. , Woodfield Tim B. F. 
Published: October 2021

AbstractWhile decades of research have enriched the knowledge of how to grow cells into mature tissues, little is yet known about the next phase: fusing of these engineered tissues into larger functional structures. The specific effect of multicellular interfaces on tissue fusion remains largely unexplored. Here, a facile 3D‐bioassembly platform is introduced to primarily study fusion of cartilage–cartilage interfaces using spheroids formed from human mesenchymal stromal cells (hMSCs) and articular chondrocytes (hACs). 3D‐bioassembly of two adjacent hMSCs spheroids displays coordinated migration and noteworthy matrix deposition while the interface between two hAC tissues lacks both cells and type‐II collagen. Cocultures contribute to increased phenotypic stability in the fusion region while close initial contact between hMSCs and hACs (mixed) yields superior hyaline differentiation over more distant, indirect cocultures. This reduced ability of potent hMSCs to fuse with mature hAC tissue further underlines the major clinical challenge that is integration. Together, this data offer the first proof of an in vitro 3D‐model to reliably study lateral fusion mechanisms between multicellular spheroids and mature cartilage tissues. Ultimately, this high‐throughput 3D‐bioassembly model provides a bridge between understanding cellular differentiation and tissue fusion and offers the potential to probe fundamental biological mechanisms that underpin organogenesis.
Achieving Efficient and Stable Perovskite Solar Cells in Ambient Air Through Non‐Halide Engineering
Authors: Wang Zhen , Jin Junjun , Zheng Yapeng , Zhang Xiang , Zhu Zhenkun , Zhou Yuan , Cui Xiaxia , Li Jinhua , Shang Minghui , Zhao Xingzhong , Liu Sheng , Tai Qidong 
Published: October 2021

AbstractThe realization of highly efficient perovskite solar cells (PSCs) in ambient air is considered to be advantageous for low‐cost commercial manufacturing. However, it is fundamentally difficult to achieve comparable device performance to that obtained in an inert atmosphere, especially when the ambient humidity is high. Here, an effective precursor engineering that simultaneously employs non‐halide lead acetate and lead thiocyanate lead sources for fabricating high‐quality methylammonium lead iodide perovskite films in ambient air with enhanced moisture tolerance, is reported. The presence of Ac– and SCN– ions not only enables the facile formation of homogeneous and highly crystalized perovskite films, but also directs the uniform growth of the crystals along the (110) direction. Accordingly, a 20.55% efficiency is demonstrated, one of the best results for air‐processed MAPbI3 PSCs, which is also the highest value achieved with non‐halide lead sources. Furthermore, the unencapsulated device shows fivefold prolonged air stability (3600 h) compared to the conventional PbI2‐based PSC. Together with the use of non‐toxic antisolvent, this strategy is fully compatible with ambient air operation and thus of great potential for practical applications.
Inverted colonic diverticulum mimic colon polyp: A case report and review
Authors: Chang Hung‐Chuen 
Published: October 2021

AbstractInverted colonic diverticula (ICD) are infrequent colonoscopy findings and usually can be misdiagnosed as colon polyps. Further endoscopic intervention including biopsy or polypectomy is dangerous and might lead to severe complications. We report a case of inverted colonic diverticulum mimic colon polyp, characteristics with Aurora rings surrounding the lesion and these rings were enhanced by narrow‐band imaging. Besides, the polypoid lesion was reverted to a typical diverticular appearance after direct water jet. Endoscopists should be aware of the possibility of ICD and be familiar with the endoscopic characteristics and maneuvers for different diagnoses of ICD from colon polyps to avoid unnecessary dangerous intervention.
Endoscopic management in a patient with pancreas divisum and recurrent pancreatitis: A case report of endoscopic ultrasound‐guided rendezvous technique
Authors: Chen Kuei‐Yu , Lin Yen‐Chih , Yen Hsu‐Heng , Chen Yang‐Yuan , Shih Kai‐Lun 
Published: October 2021

AbstractPancreatic divisum is a common congenital anomaly that can cause chronic pancreatitis or abdominal pain. Endoscopic retrograde cholangiopancreatography with pancreas duct stenting is the treatment of choice, but sometimes it is very difficult for minor papilla cannulation. We presented a difficult case in which pancreas duct stenting was performed successfully by endoscopic ultrasonography‐guided rendezvous method. The patient was free from symptoms for several years after months of pancreas duct stenting. While it is difficult to approach the minor papilla, endoscopic ultrasonography‐guided rendezvous method is a good choice.
Selfing rate variation within species is unrelated to life‐history traits or geographic range position
Authors: Prior Carly J. , Busch Jeremiah W. 
Published: October 2021

AbstractPremiseIn plants, populations and species vary widely along the continuum from outcrossing to selfing. Life‐history traits and ecological circumstances influence among‐species variation in selfing rates, but their general role in explaining intraspecific variation is unknown. Using a database of plant species, we test whether life‐history traits, geographic range position, or abundance predict selfing rate variation among populations.MethodsWe identified species where selfing rates were estimated in at least three populations at known locations. Two key life‐history traits (generation time and growth form) were used to predict within‐species selfing rate variation. Populations sampled within a species’ native range were assessed for proximity to the nearest edge and abundance. Finally, we conducted linear and segmented regressions to determine functional relationships between selfing rate and geographic range position within species.ResultsSelfing rates for woody species varied less than for herbs, which is explained by the lower average selfing rate of woody species. Relationships between selfing and peripherality or abundance significantly varied among species in their direction and magnitude. However, there was no general pattern of increased selfing toward range edges. A power analysis shows that tests of this hypothesis require studying many (i.e., 40+) populations.ConclusionsIntraspecific variation in plant mating systems is often substantial yet remains difficult to explain. Beyond sampling more populations, future tests of biogeographic hypotheses will benefit from phylogeographic information concerning specific range edges, the study of traits influencing mating system (e.g., herkogamy), and measures of abundance at local scales (e.g., population density).
Site‐Specific 5‐Formyl Cytosine Mediated DNA‐Histone Cross‐Links: Synthesis and Polymerase Bypass by Human DNA Polymerase η
Authors: Pujari Suresh S. , Wu Mingxuan , Thomforde Jenna , Wang Zhipeng A. , Chao Christopher , Olson Noelle M. , Erber Luke , Pomerantz William C. K. , Cole Philip , Tretyakova Natalia Y. 
Published: October 2021

AbstractDNA‐protein cross‐links (DPCs) between DNA epigenetic mark 5‐formylC and lysine residues of histone proteins spontaneously form in human cells. Such conjugates are likely to influence chromatin structure and mediate DNA replication, transcription, and repair, but are challenging to study due to their reversible nature. Here we report the construction of site specific, hydrolytically stable DPCs between 5fdC in DNA and K4 of histone H3 and an investigation of their effects on DNA replication. Our approach employs oxime ligation, allowing for site‐specific conjugation of histones to DNA under physiological conditions. Primer extension experiments revealed that histone H3‐DNA crosslinks blocked DNA synthesis by hPol η polymerase, but were bypassed following proteolytic processing.
Clippane: A Mechanically Interlocked Molecule (MIM) Based on Molecular Tweezers
Authors: Ibáñez Susana , Vicent Cristian , Peris Eduardo 
Published: October 2021

AbstractIn this study we report the preparation of a new mechanically interlocked molecule formed by the self‐aggregation of two metallotweezers composed by two pyrene‐imidazolylidene gold(I) arms and a pyridine‐centered pentacyclic bis‐alkynyl linker. The mechanically interlocked nature of this molecule arises from the presence of the bulkytert‐butyl groups attached to the sides of the pyrene moieties of the arms of the tweezer, which act as stoppers avoiding the dissociation of the self‐aggregated metallotweezer dimer once it is formed. By combining experimental techniques, we were able to confirm the mechanically interlocked nature of this molecule in solution, in the gas phase and in the solid state. The behavior of thetert‐butyl substituted tweezer differs greatly form that shown by the tweezer lacking of these bulky groups, whose dimeric structure is in equilibrium with the monomeric structure, therefore not showing any mechanical coercion that avoids the disassembly of the self‐aggregated structure.
Strong SHG Responses in a Beryllium‐Free Deep‐UV‐Transparent Hydroxyborate via Covalent Bond Modification
Authors: Wu Chao , Jiang Xingxing , Lin Lin , Dan Wenyan , Lin Zheshuai , Huang Zhipeng , Humphrey Mark G. , Zhang Chi 
Published: October 2021

AbstractDeep‐ultraviolet (deep‐UV) nonlinear optical (NLO) crystals are key materials in creating tunable deep‐UV lasers for frequency conversion technology. However, practical application of the sole usable crystal, KBe2BO3F2, has been hindered by the high toxicity of beryllium and its layering tendency in crystal growth. Herein, we report a beryllium‐free deep‐UV NLO material NaSr3(OH)(B9O16)[B(OH)4] (NSBOH), synthesized by a covalent bond modification strategy under hydrothermal conditions. Moisture‐stable NSBOH exhibits strong second‐harmonic generation (SHG) at 1064 nm (3.3 × KH2PO4) and 532 nm (0.55 × β‐BaB2O4), both amongst the largest powder SHG responses for a deep‐UV borate, with good phase‐matchability and a short wavelength cutoff edge (below 190 nm). NSBOH possesses a 3D covalent anionic [B9O19]∞ honeycomb‐like framework with no layering. The Sr2+ and Na+ ions, residing in the cavities of the anionic framework, act as templates for the assembly and favorable alignment of NLO‐active groups, resulting in an optimal balance between strong SHG activities and wide UV transparency. These merits indicate NSBOH is a very attractive candidate for deep‐UV NLO applications.
The role of the perceived engagement of the facilitator in a vicarious contact intervention: A school‐based field experiment in three countries
Authors: Mäkinen Viivi , Jasinskaja‐Lahti Inga , Renvik Tuuli Anna , Cocco Veronica Margherita , Lášticová Barbara , Vezzali Loris , Liebkind Karmela 
Published: October 2021

AbstractIndirect forms of intergroup contact have been shown to reduce prejudice. However, little is known about the factors that can contribute to implementing these methods as interventions in real‐life settings. In this study, we examined whether the students' perception of the facilitator's engagement in carrying out a school‐based vicarious contact intervention affects the effectiveness of the intervention among adolescents in Finland (N = 360), Italy (N = 113), and Slovakia (N = 216). As a result, the participants who perceived the facilitator as highly engaged held more positive intergroup attitudes after the intervention than those perceiving the facilitator less engaged. The results are discussed in relation to social and developmental psychological research on normative influences in adolescence and intergroup contact literature, in which normative support from authorities is considered to contribute to the extent to which contact reduces prejudice. By stressing the role of the facilitator, the results contribute both theoretically and practically to the understanding of the successful implementation of prejudice‐reduction programs. Please refer to the Supplementary Material section to find this article's Community and Social Impact Statement.
In vitro Doppler versus catheter transvalvular pressure gradients in balloon‐expandable versus self‐expanding transcatheter aortic valves
Authors: Stanová Viktória , Rieu Régis , Côté Nancy , Salaun Erwan , Rodés‐Cabau Josep , Pibarot Philippe 
Published: October 2021

AbstractObjectivesThe objective of this in vitro study was to compare Doppler versus catheter transvalvular pressure gradients (TPG) in third generations balloon‐expandable (BE) versus self‐expanding (SE) transcatheter heart valves (THV).BackgroundTPG is a key parameter to assess and follow valve hemodynamic function following transcatheter aortic valve implantation (TAVI). It remains uncertain and debated whether, and to which extent, TPGs differ according to the type of THV, that is, BE versus SE and to the method used for TPG measurement, that is, Doppler echocardiography versus cardiac catheterization.MethodsThe CoreValve EVOLUT PRO 26 mm and the SAPIEN 3 23 mm THVs were tested in a left heart simulator using a 21 mm aortic annulus under following conditions: heart rate: 70 bpm, mean aortic pressure: 100 mmHg, stroke volume: 30, 70 and 100 ml. Mean TPGs were measured by continuous‐wave Doppler and by micro‐tip pressure catheters positioned in the left ventricle and at 50 mm downstream to the tip of the THV leaflets.ResultsDoppler TPGs (9.5 ± 3.9 mmHg) were on average 40.5 ± 13.9% higher (p < 0.001) than catheter TPGs (6.3 ± 3.4 mmHg). Both Doppler and catheter TPGs were lower (p = 0.003) in the SE versus BE THVs (Doppler: 8.7 ± 3.5 vs. 10.7 ± 4.6; catheter: 5.0 ± 1.7 mmHg vs. 7.1 ± 2.2). The Doppler versus catheter difference in TPG increased with the higher flow conditions. The Doppler versus catheter difference in TPG was similar in BE versus SE THVs (3.6 ± 1.1 vs. 3.7 ± 1.4 mmHg or 42 ± 9 vs. 47 ± 9%; p = 0.58) overall and in each flow conditions.ConclusionThe Doppler TPGs are, on average, 40% higher than the catheter TPGs for both BE and SE THVs. The SE THV had lower Doppler and catheter TPGs compared to the BE THV, at normal and high flow states. The absolute and percent differences between Doppler versus catheter TPGs were similar in BE versus SE THVs.
Light‐ and pH‐regulated Water‐soluble Pseudorotaxanes Comprising a Cucurbit[7]uril and a Flavylium‐based Axle
Authors: Seco André , Yu Shilin , Tron Arnaud , McClenaghan Nathan D. , Pina Fernando , Jorge Parola A. , Basílio Nuno 
Published: October 2021

AbstractA linear double pyridinium‐terminated thread comprising a central chalcone moiety is shown to provide two independent binding sites with similar affinity for cucurbit[7]uril (CB7) macrocycles in water as judged from NMR, UV‐Visible and fluorescence spectroscopies. Association results in [2] and [3]pseudorotaxanes, which are both pH and photosensitive. Switching from the neutral chalcone to the cationic flavylium form upon irradiation at 365 nm under acidic conditions provided an enhanced CB7 association (K1:1 increases from 1.2×105 M−1 to 1.5×108 M−1), limiting spontaneous on‐thread cucurbituril shuttling. This co‐conformational change in the [2]pseudorotaxane is reversible in the dark with kobs=4.1×10−4 s−1. Threading the flavylium moiety into CB7 leads to a dramatic increase in the fluorescence quantum yield, from 0.29 in the free axle to 0.97 in the [2]pseudorotaxane and 1.0 in the [3]pseudorotaxane.