bluuebunny/crossref_metadata_2025 huggingface dataset:
Advances in Biomaterial‐Based Spinal Cord Injury Repair
Authors: Shen He , Fan Caixia , You Zhifeng , Xiao Zhifeng , Zhao Yannan , Dai Jianwu
Published: December 2021

Spinal cord injury (SCI) often leads to the loss of motor and sensory functions and is a major challenge in neurological clinical practice. Understanding the pathophysiological changes and the inhibitory microenvironment is crucial to enable the identification of potential mechanisms for functional restoration and to provide guidance for the development of efficient treatment and repair strategies. To date, the implantation of specifically functionalized biomaterials in the lesion area has been shown to help promote axon regeneration and facilitate neuronal circuit generation by remolding SCI microenvironments. Moreover, structural and functional restoration of the spinal cord through the transplantation of naive spinal cord tissue grafts from adult donors, artificial spinal cord‐like tissue developed from tissue engineering, and 3D printing will open up new avenues for SCI treatment. This review focuses on the dynamic pathophysiological changes in SCI microenvironments, biomaterials for SCI repairs, strategies for restoring spinal cord structure and function, experimental animal models, regenerative mechanisms, and clinical studies for SCI repair. The current status, recent advances, challenges, and prospects of scaffold‐based SCI repair from basic to clinical settings are summarized and discussed, to provide a reference that will help to guide the future exploration and development of spinal cord regeneration strategies.
Creating a Ferromagnetic Ground State with Tc Above Room Temperature in a Paramagnetic Alloy through Non‐Equilibrium Nanostructuring
Authors: Ye Xinglong , Fortunato Nuno , Sarkar Abhishek , Geßwein Holger , Wang Di , Chen Xiang , Eggert Benedikt , Wende Heiko , Brand Richard A. , Zhang Hongbin , Hahn Horst , Kruk Robert
Published: December 2021

Materials with strong magnetostructural coupling have complex energy landscapes featuring multiple local ground states, thus making it possible to switch among distinct magnetic‐electronic properties. However, these energy minima are rarely accessible by a mere application of an external stimuli to the system in equilibrium state. A ferromagnetic ground state, with Tc above room temperature, can be created in an initially paramagnetic alloy by nonequilibrium nanostructuring. By a dealloying process, bulk chemically disordered FeRh alloys are transformed into a nanoporous structure with the topology of a few nanometer‐sized ligaments and nodes. Magnetometry and Mössbauer spectroscopy reveal the coexistence of two magnetic ground states, a conventional low‐temperature spin‐glass and a hitherto‐unknown robust ferromagnetic phase. The emergence of the ferromagnetic phase is validated by density functional theory calculations showing that local tetragonal distortion induced by surface stress favors ferromagnetic ordering. The study provides a means for reaching conventionally inaccessible magnetic states, resulting in a complete on/off ferromagnetic–paramagnetic switching over a broad temperature range.
Hierarchical Piezoresponse in Collagen
Authors: Cartwright Victoria F. , Brown Cameron P.
Published: December 2021

The piezoelectric nature of collagen has been known for decades, yet its manifestation across, and interactions between, hierarchies remains elusive. Here, piezoelectricity at the tropocollagen‐, microfibril‐, and fibril‐level hierarchies is examined experimentally, using collagen assembled from solution onto muscovite mica substrates. An amplification of the d15 response of 35–50% is observed between the tropocollagen and fibril levels, with no difference observed between the microfibril and fibril levels. Comparison of experimental results with simulation indicates the potential to optimize collagen piezoresponse via tropocollagen packing to exceed the piezoelectric properties of native collagen fibrils. By improving electromechanical performance through adjustments to winding angle and packing, it may therefore be possible to utilize collagen in low‐cost, biodegradable, and biocompatible sensing or harvesting devices.
Stereoselective Cyclopropanation of Boron Dipyrromethene (BODIPY) Derivatives by an Organocascade Reaction
Authors: Dočekal Vojtěch , Koberová Tereza , Hrabovský Jan , Vopálenská Andrea , Gyepes Róbert , Císařová Ivana , Rios Ramon , Veselý Jan
Published: December 2021

The synthesis of enantiopure chiral boron dipyrromethenes (BODIPYs) is of importance due the intrinsic properties of BODIPYs as fluorophores that could be used as probes for molecular sensing. The present study reports an asymmetric organocatalytic cascade reaction of meso‐chloromethyl BODIPY derivatives with α,β‐unsaturated aldehydes catalyzed by a chiral secondary amine. The corresponding BODIPY‐derived cyclopropanes were produced in isolated yields 66–98%, and with diastereomeric ratios 3/2–>20/1, and 92–99% ee for major diastereomer. The synthetic utility of the protocol was exemplified on a set of additional transformations of the corresponding optically pure compounds. In addition, a study explaining the reaction mechanism (DFT computations) and photophysical characterization of all enantioenriched products were accomplished.

magnified image
Expanded phenotype of primary ciliary dyskinesia related to DRC1 pathogenic variant with dysmorphisms and vascular anomalies
Authors: LeBlanc Samuel , Allain Eric P. , Girouard Gabriel , Mallet Marcel , Amor Mouna Ben
Published: December 2021

We present a case of a female diagnosed with primary ciliary dyskinesia (PCD) type 21 with non‐previously reported extrapulmonary symptoms, including facial features and congenital vascular anomalies. Whole genome sequencing in our patient revealed a homozygous pathogenic variant in the DRC1 gene and no other notable structural nor punctual variants. This case demonstrates a unique clinical manifestation of PCD, which is possibly associated with the presence of a homozygous pathogenic DRC1 variant. Therefore, we suggest that analysis of DRC1 be considered with PCD type 21 when such features are present.
Trifluoroethanol as a Unique Additive for the Chemoselective Electrooxidation of Enamines to Access Unsymmetrically Substituted NH‐Pyrroles
Authors: Baidya Mrinmay , Maiti Debabrata , Roy Lisa , De Sarkar Suman
Published: December 2021

An electrochemical method for the synthesis of unsymmetrically substituted NH‐pyrroles is described. The synthetic strategy comprises a challenging heterocoupling between two structurally diverse enamines via sequential chemoselective oxidation, addition, and cyclization processes. A series of aryl‐ and alkyl‐substituted enamines were effectively cross‐coupled from an equimolar mixture to synthesize various unsymmetrical pyrrole derivatives up to 84 % yield. The desired cross‐coupling was achieved by tuning the oxidation potential of the enamines by utilizing a “magic effect” of the additive trifluoroethanol (TFE). Additionally, extensive computational studies reveal the unique role of TFE in promoting the heterocoupling process by regulating the activation energies of the reaction steps through H‐bonding and C−H⋅⋅⋅π interactions. Importantly, the developed electrochemical protocol was found to be equally efficient for the homocoupling of enamines to form symmetric pyrroles up to 92 % yield.
Fluorescence Imaging of Mitochondrial DNA Base Excision Repair Reveals Dynamics of Oxidative Stress Responses
Authors: Jun Yong Woong , Albarran Eddy , Wilson David L. , Ding Jun , Kool Eric T.
Published: December 2021

Mitochondrial function in cells declines with aging and with neurodegeneration, due in large part to accumulated mutations in mitochondrial DNA (mtDNA) that arise from deficient DNA repair. However, measuring this repair activity is challenging. We employ a molecular approach for visualizing mitochondrial base excision repair (BER) activity in situ by use of a fluorescent probe (UBER) that reacts rapidly with AP sites resulting from BER activity. Administering the probe to cultured cells revealed signals that were localized to mitochondria, enabling selective observation of mtDNA BER intermediates. The probe showed elevated DNA repair activity under oxidative stress, and responded to suppression of glycosylase activity. Furthermore, the probe illuminated the time lag between the initiation of oxidative stress and the initial step of BER. Absence of MTH1 in cells resulted in elevated demand for BER activity upon extended oxidative stress, while the absence of OGG1 activity limited glycosylation capacity.
Maximizing Step‐Normalized Increases in Molecular Complexity: Formal [4+2+2+2] Photoinduced Cyclization Cascade to Access Polyheterocycles Possessing Privileged Substructures
Authors: Reddy D. Sai , Novitskiy Ivan M. , Kutateladze Andrei G.
Published: December 2021

A new complexity building photoinduced cascade which amounts to an unprecedented formal [4+2+2+2] cycloaddition topology is developed to access complex nitrogen polyheterocycles. This photocascade is initiated by the excited state intramolecular proton transfer (ESIPT) in aromatic amino ketones with tethered dual unsaturated pendants, i.e. pyrrole and alkenic moieties, resulting in the formation of four σ‐bonds and setting six new stereogenic centers in a single experimentally simple photochemical step with up to 220 mcbit complexity increases.
Structural Elucidation of Cryptic Algaecides in Marine Algal‐Bacterial Symbioses by NMR Spectroscopy and MicroED
Authors: Park Jong‐Duk , Li Yuchen , Moon Kyuho , Han Esther J. , Lee Seoung Rak , Seyedsayamdost Mohammad R.
Published: December 2021

Microbial secondary metabolite discovery is often conducted in pure monocultures. In a natural setting, however, where metabolites are constantly exchanged, biosynthetic precursors are likely provided by symbionts or hosts. In the current work, we report eight novel and architecturally unusual secondary metabolites synthesized by the bacterial symbiont Phaeobacter inhibens from precursors that, in a native context, would be provided by their algal hosts. Three of these were produced at low titres and their structures were determined de novo using the emerging microcrystal electron diffraction method. Some of the new metabolites exhibited potent algaecidal activity suggesting that the bacterial symbiont can convert algal precursors, tryptophan and sinapic acid, into complex cytotoxins. Our results have important implications for the parasitic phase of algal‐bacterial symbiotic interactions.
A Bright, Renal‐Clearable NIR‐II Brush Macromolecular Probe with Long Blood Circulation Time for Kidney Disease Bioimaging
Authors: Yao Chenzhi , Chen Ying , Zhao Mengyao , Wang Shangfeng , Wu Bin , Yang Yiwei , Yin Dongrui , Yu Peng , Zhang Hongxin , Zhang Fan
Published: December 2021

Early detection of kidney disease is of vital importance due to its current prevalence worldwide. Fluorescence imaging, especially in the second near‐infrared window (NIR‐II) has been regarded as a promising technique for the early diagnosis of kidney disease due to the superior resolution and sensitivity. However, the reported NIR‐II organic renal‐clearable probes are hampered by their low brightness (ϵmaxΦf>1000 nm<10 M−1 cm−1) and limited blood circulation time (t1/2<2 h), which impede the targeted imaging performance. Herein, we develop the aza‐boron‐dipyrromethene (aza‐BODIPY) brush macromolecular probes (Fudan BDIPY Probes (FBP 912)) with high brightness (ϵmaxΦf>1000 nm≈60 M−1 cm−1), which is about 10‐fold higher than that of previously reported NIR‐II renal‐clearable organic probes. FBP 912 exhibits an average diameter of ≈4 nm and high renal clearance efficiency (≈65 % excretion through the kidney within 12 h), showing superior performance for non‐invasively diagnosis of renal ischemia‐reperfusion injury (RIR) earlier than clinical serum‐based protocols. Additionally, the high molecular weight polymer brush enables FBP 912 with prolonged circulation time (t1/2≈6.1 h) and higher brightness than traditional PEGylated renal‐clearable control fluorophores (t1/2<2 h), facilitating for 4T1 tumor passive targeted imaging and renal cell carcinoma active targeted imaging with higher signal‐to‐noise ratio and extended retention time.
Direkte Katalytische C‐Glykosylierung von Arenen: beschleunigte Synthese des Remdesivir‐Nucleosids**
Authors: Obradors Carla , Mitschke Benjamin , Aukland Miles H. , Leutzsch Markus , Grossmann Oleg , Brunen Sebastian , Schwengers Sebastian A. , List Benjamin
Published: December 2021

Seit Beginn des Jahres 2020 wird nach einer effektiven Lösung im Kampf gegen SARS‐CoV‐2 gesucht, vor allem durch Entwicklung verlässlicher Impfstoffe, welche die Verbreitung des Virus verhindern, und durch die Untersuchung bereits für andere Indikationen zugelassener Wirkstoffe. Diesbezüglich ist die Anwendung der antiviralen Prodrug Remdesivir immer noch am weitesten verbreitet, allerdings beschränkt sich die Synthese auf Schutzgruppen, sauerstoffsensitive Reagenzien und kryogene Temperaturen, weshalb eine kosteneffiziente Herstellung nicht immer gewährleistet werden kann. Um zur Lösung dieses Problems beizutragen, konzentrierten wir uns auf die Entwicklung einer direkten Addition von (Hetero)arenen an ungeschützte Zucker. Hier berichten wir von einer silyliumkatalysierten und vollkommen stereoselektiven C‐Glykosylierung, die zunächst offenkettige Polyole liefert, welche schließlich durch Cyclisierung unter kinetischer oder thermodynamischer Kontrolle zur α‐ oder β‐Furanose umgesetzt werden. Die Methode ermöglicht raschen Zugang zu Remdesivir‐Intermediat GS‐441524 nach anschließender Mn‐katalysierter C−H‐Oxidation sowie Deoxycyanierung.
A Hydrogen‐Bonded Ravel Assembled by Anion Coordination
Authors: Zhao Xiaotong , Wang Heng , Li Boyang , Zhang Wenyao , Li Xiaopeng , Zhao Wei , Janiak Christoph , Heard Andrew W. , Yang Xiao‐Juan , Wu Biao
Published: December 2021

Anion‐coordination‐driven assembly (ACDA) is showing increasing power in the construction of anionic supramolecular architectures. Herein, by expanding the anion centers from oxoanion (phosphate or sulfate) to organic tris‐carboxylates, an Archimedean solid (truncated tetrahedron) and a highly entangled, double‐walled tetrahedron featuring a ravel topology have been assembled with tris‐bis(urea) ligands. The results demonstrate the promising ability of tris‐carboxylates as new anion coordination centers in constructing novel topologies with increasing complexity and diversity compared to phosphate or sulfate ions on account of the modifiable size and easy functionalization character of these organic anions.
Proton/Electron Donors Enhancing Electrocatalytic Activity of Supported Conjugated Microporous Polymers for CO2Reduction
Authors: Wang Rong , Wang Xinyue , Weng Weijun , Yao Ying , Kidkhunthod Pinit , Wang Changchun , Hou Yang , Guo Jia
Published: December 2021

Metal phthalocyanines (MePc) hold great promise in electrochemical reduction of CO2to value‐added chemicals, whereas the catalytic activity of MePc‐containing polymers often suffers from a limited molecular modulation strategy. Herein, we synthesize an ultrathin conjugated microporous polymer sheath around carbon nanotubes by an ionothermal copolymerization of CoPc and H2Pc via the Scholl reaction. Given the H2Pc‐mediated regulation in the synthesis, CoIImetal is well preserved in the form of single atoms on the polymer sheath of the carbon nanotubes. With the synergistic effect of H2Pc moieties as proton/electron donors, the composites can selectively reduce CO2to CO with a high Faradaic efficiency (max. 97 % at −0.9 V) in broad potential windows, exceptional turnover frequency (97 592 h−1at −0.65 V) and large current density (>200 mA cm−2). It is thus desirable to develop a family of heterogeneous polymerized MePc with molecularly regulating electrocatalytic activity.
Dynamic three‐dimensional virtual environment to improve learning of anatomical structures
Authors: Duraes Martha , Akkari Mohamed , Jeandel Clément , Moreno Benjamin , Subsol Gérard , Duflos Claire , Captier Guillaume
Published: December 2021

Increasing number of medical students and limited availability of cadavers have led to a reduction in anatomy teaching through human cadaveric dissection. These changes triggered the emergence of innovative teaching and learning strategies in order to maximize students learning of anatomy. An alternative approach to traditional dissection was presented in an effort to improve content delivery and student satisfaction. The objective of this study is to acquire three‐dimensional (3D) anatomical data using structured‐light surface scanning to create a dynamic four‐dimensional (4D) dissection tool of four regions: neck, male inguinal and femoral areas, female perineum, and brachial plexus. At each dissection step, identified anatomical structures were scanned using a 3D surface scanner (Artec Spider™). Resulting 3D color meshes were overlaid to create a 4D (3D+time) environment. An educational interface was created for neck dissection. Its implementation in the visualization platform allowed 4D virtual dissection by navigating from surface to deep layers and vice versa. A group of 28 second‐year medical students and 17 first‐year surgery residents completed a satisfaction survey. A majority of medical students (96.4%) and 100% of surgery residents said that they would recommend this tool to their colleagues. According to surgery residents, the main elements of this virtual tool were the realistic high‐quality of 3D acquisitions and possibility to focus on each anatomical structure. As for medical students, major elements were the interactivity and entertainment aspect, precision, and accuracy of anatomical structures. This approach proves that innovative solutions to anatomy education can be found to help to maintain critical content and student satisfaction in anatomy curriculum.
Water‐Involved Ring‐Opening of 4‐Phenyl‐1,2,4‐triazoline‐3,5‐dione for “Photo‐Clicked” Access to Carbamoyl Formazan Photoswitches In Situ
Authors: Zheng Yuanqin , Zhou Yuqiao , Zhang Yan , Deng Pengchi , Zhao Xiaohu , Jiang Shichao , Du Guangxi , Shen Xin , Xie Xinyu , Su Zhishan , Yu Zhipeng
Published: December 2021

Cyclic azodicarbonyl derivatives, particularly 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione (PTAD), commonly serve as arenophile, dienophile, enophile and electrophile. Perplexed by its instability in aqueous environment, there are few studies focused on the transient intermediate produced by hydrolysis of PTAD to achieve synthetic significance. Herein, we describe a “photo‐click” method that involves nitrile imine (NI) from diarylsydnone to capture the diazenecarbonyl‐phenyl‐carbamic acid (DACPA) generated by water‐promoted ring‐opening of PTAD. DFT calculation reveal that H‐bonding interactions between PTAD and water are vital to form DACPA which exhibited an umpolung effect during ligation by nature bond orbit (NBO) analysis. The ultra‐fast ligation resulted in carbamoyl formazans, as a unique Z↔E photo‐switchable linker on target molecules, including peptide and drugs, with excellent anti‐fatigue performance. This strategy is showcased to construct highly functionalized carbamoyl formazans in situ for photo‐pharmacology and material studies, which also expands the chemistry of PTAD in aqueous media.
Parsec‐scale view of CSS/GPS sources at 327 MHz
Authors: Dallacasa Daniele , Orienti Monica
Published: December 2021

Global very long baseline interferometry (VLBI) observations at low frequencies are of great importance since they allow us to test the oldest part of the relativistic electron populations in young radio sources. At 327 MHz ( 92 cm), the most compact regions are self‐absorbed, and the number of cores detected is very small. This could provide useful measurements of the magnetic field in the relativistic plasma, to be compared with the equipartition field derived from minimum energy arguments. Partial self‐absorption takes place also in hot‐spots. However, disentangling the hot‐spot emission from that of the lobe turned out to be rather difficult. On the other hand, a clearer and more complete characterization of the volumes occupied by the magnetized relativistic plasma and its total energy content can be obtained at 327 MHz. In turn, an independent estimate of the source age can be inferred, on the basis of simple assumptions on the jet power. Here, we show that the ages derived in this way (between and year) are consistent with the radiative ages determined from the break frequency in the radio spectrum.
Therapeutics studies and biological properties of Teucrium polium (Lamiaceae)
Authors: Rahmouni Fatma , Saoudi Mongi , Rebai Tarek
Published: December 2021

Teucrium polium has been used in traditional medicine as antifungal, antipyretic, antispasmodic, and antibacterial. It is consumed by many jordanians for the treatment of many diseases. The effects of this plant have been investigated in kidney, liver, and brain. Its antidiabetic, antimicrobial, antioxidant, and anticancer effects have been introduced. Polyphenolic compound, flavonoids, monoterpenes, alkanoides, and essential oils were identified. Several studies revealed that this plant has a hypoglycemic effect and can help to control blood sugar. It was reported that plants containing flavonoids and phenolics compounds exhibit a large array of biological activities like genotoxicity (chromosomal aberrations and sister chromatid exchange) and oxidative stress damage. These phytochemicals are found in herbal and vegetables plants, as well as being reliably protective against oxidative stress damage and lipid peroxidation. In addition, T. polium has secondary effects on different organs, namely liver, kidney and at high doses this plant becomes toxic. In conclusion, this review investigates many pharmacologicals properties and side effects of T. polium.
BRAFV600E mutation test on fine‐needle aspiration specimens of thyroid nodules: Clinical correlations for 4600 patients
Authors: Chen Huang , Song Aiping , Wang Ye , He Yifan , Tong Jie , Di Jinxi , Li Chun , Zhou Zhongren , Cai Xiaopin , Zhong Dingrong , Da Jiping
Published: December 2021

Background

The BRAFV600E mutation is valuable for the diagnosis, prognosis, and therapy of papillary thyroid cancer (PTC). However, studies related to this mutation have involved only a small number of patients. Therefore, we performed a large‐scale analysis from a single institute to evaluate the accuracy of combined fine‐needle aspiration (FNA) and BRAFV600E mutation tests for PTC diagnosis.

Methods

A total of 4600 patients with thyroid nodules who underwent both FNA cytology and BRAFV600E mutation analysis on FNA specimens were enrolled. The association between the BRAFV600E mutation and clinicopathological features was analyzed. A separate analysis was performed for the 311 patients who underwent repeated FNA for comparison of cytological evaluation and BRAFV600E mutation results. The diagnostic efficacy of the BRAFV600E mutation test and cytologic diagnoses was evaluated for 516 patients who underwent preoperative FNA tests in comparison with conclusive postoperative histopathologic results.

Results

The cytology results of all 4600 FNA samples were categorized according to The Bethesda System for Reporting Thyroid Cytology (TBSRTC) stages I–VI, which accounted for 11.76%, 60.02%, 6.46%, 3.61%, 6.71%, and 11.43% of the samples, respectively. The BRAFV600E mutation was detected in 762 (16.57%) FNA samples, with rates of 1.48%, 0.87%, 20.20%, 3.01%, 66.02%, and 87.81% for TBSRTC I–VI lesions, respectively. Among the 311 repeat FNA cases, 81.0% of the BRAFV600E‐positive and 4.3% of the BRAFV600E‐negative specimens with an initial indication of cytological non‐malignancy were ultimately diagnosed as malignant by repeat FNA (p < 0.001). Among the 516 patients who underwent thyroidectomy, the sensitivity and specificity of the BRAFV600E mutation test alone for PTC diagnosis were 76.71% and 100.0%, respectively, which increased to 96.62% and 88.03%, respectively, when combining the BRAFV600E mutation test with cytology. BRAFV600E mutation was significantly associated with lymph node metastasis (p < 0.001), but not with age, gender, or tumor size.

Conclusions

The BRAFV600E mutation test in FNA samples has potential to reduce false negatives in PTC diagnosis, and therefore plays an important role in the diagnosis of thyroid nodules, especially those with an indeterminate or nondiagnostic cytology, which should be considered for repeat FNA.
Tailoring Enzyme Stringency Masks the Multispecificity of a Lyngbyatoxin (Indolactam Alkaloid) Nonribosomal Peptide Synthetase
Authors: Soeriyadi Angela H. , Ongley Sarah E. , Kehr Jan‐Christoph , Pickford Russel , Dittmann Elke , Neilan Brett A.
Published: December 2021

Indolactam alkaloids are activators of protein kinase C (PKC) and are of pharmacological interest for the treatment of pathologies involving PKC dysregulation. The marine cyanobacterial nonribosomal peptide synthetase (NRPS) pathway for lyngbyatoxin biosynthesis, which we previously expressed in E. coli, was studied for its amenability towards the biosynthesis of indolactam variants. Modification of culture conditions for our E. coli heterologous expression host and analysis of pathway products suggested the native lyngbyatoxin pathway NRPS does possess a degree of relaxed specificity. Site‐directed mutagenesis of two positions within the adenylation domain (A‐domain) substrate‐binding pocket was performed, resulting in an alteration of substrate preference between valine, isoleucine, and leucine. We observed relative congruence of in vitro substrate activation by the LtxA NRPS to in vivo product formation. While there was a preference for isoleucine over leucine, the substitution of alternative tailoring domains may unveil the true in vivo effects of the mutations introduced herein.
A Conformationally Stable Acyclic β‐Hairpin Scaffold Tolerating the Incorporation of Poorly β‐Sheet‐Prone Amino Acids
Authors: Stanojlovic Vesna , Müller Anna , Moazzam Ali , Hinterholzer Arthur , Ożga Katarzyna , Berlicki Łukasz , Schubert Mario , Cabrele Chiara
Published: December 2021

The β‐hairpin is a structural element of native proteins, but it is also a useful artificial scaffold for finding lead compounds to convert into peptidomimetics or non‐peptide structures for drug discovery. Since linear peptides are synthetically more easily accessible than cyclic ones, but are structurally less well‐defined, we propose XWXWXpPXK(/R)X(R) as an acyclic but still rigid β‐hairpin scaffold that is robust enough to accommodate different types of side chains, regardless of the secondary‐structure propensity of the X residues. The high conformational stability of the scaffold results from tight contacts between cross‐strand cationic and aromatic side chains, combined with the strong tendency of the d‐Pro‐l‐Pro dipeptide to induce a type II′ β‐turn. To demonstrate the robustness of the scaffold, we elucidated the NMR structures and performed molecular dynamics (MD) simulations of a series of peptides displaying mainly non‐β‐branched, poorly β‐sheet‐prone residues at the X positions. Both the NMR and MD data confirm that our acyclic β‐hairpin scaffold is highly versatile as regards the amino‐acid composition of the β‐sheet face opposite to the cationic−aromatic one.
Transcatheter edge‐to‐edge mitral valve repair: Should we stay tied to COAPT tiers?
Authors: Saia Francesco
Published: December 2021

Key Points

What the article teaches. Patients with secondary mitral regurgitation (SMR) undergoing transcatheter edge‐to‐edge mitral valve repair (TEER) have different prognosis based on eligibility criteria in the COAPT trial and on different echocardiographic tiers for enrollment in the same trial.

How it will impact practice. Patient selection for TEER should be based on an integrative approach rather than on a single parameter, and largely guided by the COAPT trial enrollment criteria.

What new research/study would help answer the question posed. Further studies are needed to clearly identify patients subgroups that could benefit from TEER and, within them, to identify parameters that may help stratifying patients with different outcomes.
Outflow graft obstruction in patients with left ventricular assist devices: Stenting the kink
Authors: Postalian Alexander , Krajcer Zvonimir
Published: December 2021

Key Points

Outflow graft obstruction (OGO) is a feared complication in patients with left ventricular assist devices.

It can be caused by graft kinking or twisting, external compression, or internal material deposition.

The best endovascular approach for treating this complication is not well established.

The authors report their institutional experience treating OGO in patients with HeartMate 3 devices, describing a straightforward approach that appears safe and feasible for a large proportion of patients.
Sterically Crowded Tris(2‐(trimethylsilyl)phenyl)phosphine – Is it Still a Ligand?
Authors: Gildenast Hans , Garg Felix , Englert Ulli
Published: December 2021

Tris(2‐(trimethylsilyl)phenyl)phosphine, P(o‐TMSC6H4)3, was synthesised and characterised in solution and in the solid state. The large steric bulk prevents most reactions of the phosphorus donor and makes the compound air stable both in the solid state as well as in solution. This shielded phosphine can still undergo three reactions, namely protonation, oxidation to the phosphine oxide under harsh conditions and complexation to AuI, thus forming a complex with linear coordination. Unexpectedly, complexation was unsuccessful with a range of other metal cations. Neither PdII, PtII, ZnII nor HgII reacted and even the remaining coinage metal cations CuI and AgI could not be coordinated. Both the parent molecule as well as the reaction products were structurally characterised by single crystal X‐ray diffraction, and the conformational change of geometry required to accommodate the additional atoms was analysed in detail. Apart from chemical oxidation with H2O2, P(o‐TMSC6H4)3 displays reversible electrochemical oxidation with a potential not unlike the one of sterically unencumbered phosphines for which the oxidation is usually not reversible. P(o‐TMSC6H4)3 can thus be considered a model compound for the investigation of the electronic properties of sterically unencumbered phosphines.
Two Faces of the Same Coin: Coupling X‐Ray Absorption and NMR Spectroscopies to Investigate the Exchange Reaction Between Prototypical Cu Coordination Complexes
Authors: Del Giudice Daniele , Tavani Francesco , Di Berto Mancini Marika , Frateloreto Federico , Busato Matteo , Oliveira De Souza Danilo , Cenesi Flavia , Lanzalunga Osvaldo , Di Stefano Stefano , D'Angelo Paola
Published: December 2021

The satisfactory rationalization of complex reactive pathways in solution chemistry may greatly benefit from the combined use of advanced experimental and theoretical complementary methods of analysis. In this work, we combine X‐Ray Absorption and 1H NMR spectroscopies with state‐of‐the‐art Multivariate Curve Resolution and theoretical analyses to gain a comprehensive view on a prototypical reaction involving the variation of the oxidation state and local structure environment of a selected metal ion coordinated by organic ligands. Specifically, we investigate the 2‐cyano‐2‐phenylpropanoic acid reduction of the octahedral complex established by the Cu2+ ion with terpyridine to the tetrahedral complex formed by Cu+ and neocuproine. Through our interdisciplinary approach we gain insights into the nature, concentration time evolution and structures of the key metal (XAS measurements) and organic (1H NMR measurements) species under reaction. We believe our method may prove to be useful in the toolbox necessary to understand the mechanisms of reactive processes of interest in solution.
Isolation of Cyclic Aluminium Polysulfides by Stepwise Sulfurization
Authors: Xu Huihui , Weetman Catherine , Hanusch Franziska , Inoue Shigeyoshi
Published: December 2021

Despite the notable progress in aluminium chalcogenides, their sulfur congeners have rarely been isolated under mild conditions owing to limited synthetic precursors and methods. Herein, facile isolation of diverse molecular aluminium sulfides is achievable, by the reaction of N‐heterocyclic carbene‐stabilized terphenyl dihydridoaluminium (1) with various thiation reagents. Different to the known dihydridoaluminium 1Tipp, 1 features balanced stability and reactivity at the Al center. It is this balance that enables the first monomeric aluminium hydride hydrogensulfide 2, the six‐membered cyclic aluminium polysulfide 4 and the five‐membered cyclic aluminium polysulfide 6 to be isolated, by reaction with various equivalents of elemental sulfur. Moreover, a rare aluminium heterocyclic sulfide with Al−S−P five‐membered ring (7) was obtained in a controlled manner. All new compounds were fully characterized by multinuclear NMR spectroscopy and elemental analysis. Their structures were confirmed by single‐crystal X‐ray diffraction studies.
Energy Efficient and Reliable K Best Detection Approach with Hybrid Decomposition for WiMAX Applications
Authors: K.B. Bavithra , R Siva Kumar
Published: December 2021

K‐best detection algorithm placed a vital role for best signal detection in multi‐input multi‐output (MIMO) systems. The major challenge in K‐best approach is that, if the number of users increases, the preprocessing complexity also increases. To mitigate this limitations, CLD (Cholesky factorization + LDLT factorization)‐based decomposition process is proposed with sorted integer Gauss transformation (SIGT) to design 4 × 4 MIMO system. It limits the processing complexity by reducing the number of pipelining stages. Experimental results exhibit that the novel CLD‐based K‐best detector reduces power consumption by 33.52%, 16.29%, 25.65%, 9.6%, and 6.61% and increases the throughput by 69.62%, 68.84%, 62.61%, 4.73%, and 66.04% when compared with K‐best detector, modified K‐best detector, variable K‐best detector, low‐complexity K‐best, and K‐best with hybrid merge network. The proposed K‐best detection scheme increases the energy efficiency by 79.80%, 73.92%, 72.21%, 13.72%, and 68.28% when compared with the existing techniques such as K‐best detection, modified K‐best detection, variable K‐best, low‐complexity K‐best, and K‐best with hybrid merge network.
Archäologisches Haus am Petriplatz – massive Außenwandkonstruktion
Authors: Schermer Detleff , Nagler Florian , Schwabe Almut
Published: December 2021

Der Petriplatz in Berlin zählt zu einem der frühesten Besiedelungsorte Berlins aus dem 12. Jh. In diesem Bereich wird im Auftrag des Berliner Senats aktuell das Archäologische Haus errichtet, welches die mit dem Ort verbundenen Funde integrieren und den Besuchern direkt zugänglich machen soll. Die oberirdischen Geschosse werden als archäologische Werkstätten und Sammlungsräume dienen und einen Vortragssaal aufweisen. Die gewählte Konstruktion des siebengeschossigen Gebäudes passt sich den örtlichen Randbedingungen an: So erfolgt die Gründung auf Bohrpfählen, um den Eingriff in die Fundstätte zu minimieren und gleichzeitig Elemente für die Geothermie zu schaffen. Aus der statischen Funktion sowie den Brandschutzanforderungen und dem Schutz gegen Außenlärm ergab sich die Notwendigkeit, die Tragkonstruktion massiv in Stahlbeton auszuführen. Als quasi monolithischer Außenwandaufbau im Regelbereich wurde eine neue Systematik mittels tragender Stahlbetoninnenschale und nicht tragender Ausfachung aus hochwärmedämmendem Planziegelmauerwerk entwickelt. Neben dem Lastabtrag waren insbesondere die Themen der Rissesicherheit, der Ausführung und des Zusammenwirkens von Beton und Mauerwerk zu beachten.
Energieeffizienz weitergedacht: die thermisch aktivierte Gebäudehülle als Teil einer Prozesskette
Authors: Maier Andreas , Hochrein Martin , Schneider Jens , Joppien Anett‐Maud , Beck Martin
Published: December 2021

Die öffentliche Diskussion zur Energiewende findet oftmals ausschließlich im Kontext elektrischer Energie statt. Gerade im Industriesektor spielt jedoch auch die thermische Energie eine wesentliche Rolle. Entgegen einem rein dogmatischen Ansatz Energie zu „sparen”, geht es darum, das Energiesystem als Ganzes zu verstehen und energetische Abhängigkeiten zu erkennen. Leitidee des Forschungsprojekts ETA‐Fabrik ist es, die richtige Energieform (Primärenergiebedarf) in der notwendigen Menge (Endenergiebedarf) zur richtigen Zeit (energieflexibel) am richtigen Ort (effiziente Infrastruktur) einzusetzen. Dabei wurde über die bisher stets isoliert betrachtete Optimierung von Einzelkomponenten (z. B. Maschine, Kühlsystem, Gebäudedämmung) hinaus das gesamte System einer Produktionsfabrik betrachtet und auf dem Campus der TU Darmstadt eine Modellfabrik errichtet, in der Gebäude, Haustechnik und Maschinen durch die drei Ebenen der Gebäudeautomation synergetisch miteinander verknüpft wurden. Einen wesentlichen Beitrag zur Energieeffizienzsteigerung liefert hierfür die durch oberflächennahe, wasserführende, kapillarähnliche Rohrleitungsnetze thermisch aktivierte Gebäudehülle aus Beton. Diese multifunktionalen Wand‐ und Dachelemente vereinen die Funktionen des Tragens, des Dämmens, des Begrenzens und der thermischen Interaktion und fungieren somit als riesige Heiz‐ und Kühlflächen. Der Aufsatz ist eine inhaltliche Fortsetzung des Beitrags aus der Bautechnik 03/2014 und stellt die erzielten Projektergebnisse mit Fokus auf der baulichen Umsetzung vor. Hintergründe und Zielstellungen des Projekts werden aufgegriffen, Forschungsrandbedingungen dargelegt und die Energieeinsparpotenziale vorgestellt. Neben der kurzen Beschreibung der umgesetzten thermischen Vernetzung und der dafür gebauten Gebäudehüllelemente als Fortschreibung der bereits vorgestellten Konzepte werden die thermische Leistungsfähigkeit der Gebäudehülle sowie deren Beitrag zur Behaglichkeit in der Produktionshalle erläutert. Das architektonische Konzept sowie eine kritische Würdigung der interdisziplinären Zusammenarbeit im Planungsprozess einer vernetzten Fabrik schließen diese Reihe ab.
Evidence for selection and spatially distinct patterns found in a putative zona pellucida gene in Pacific cod, and implications for management
Authors: Spies Ingrid , Drinan Daniel P. , Petrou Eleni L. , Spurr Rory , Tarpey Carolyn , Hartinger Theodore , Larson Wes , Hauser Lorenz
Published: December 2021

Genetic differentiation has been observed in marine species even when no obvious barriers to gene flow exist, and understanding such differentiation is essential for effective fisheries management. Highly differentiated outlier loci can provide information on how genetic variation might not only contribute to local adaptation but may also be affected by historical demographic events. A locus which aligned to a predicted zona pellucida sperm‐binding protein 3 gene (ZP3) in Atlantic cod (Gadus morhua) was previously identified as the highest outlier based on FST in a RADseq study of Pacific cod (Gadus macrocephalus) across the West Coast of North America. However, because of the limited length of the RAD sequence and restricted geographic area of sampling, no conclusion on the functional significance of the observed variation was possible. In other marine species, ZP3 is involved in reproductive isolation, local adaptation, and has neofunctionalized as an antifreeze gene, and so it may provide important insights in functional population structure of Pacific cod. Here, we sequenced a 544‐bp region of ZP3 in 230 Pacific cod collected from throughout their geographic range. We observed striking patterns of spatial structuring of ZP3 haplotypes, with a sharp break near Kodiak, Alaska, USA where populations within ~200 km of each other are nearly fixed for different haplotypes, contrasting a pattern of isolation by distance at other genetic markers in this region (FST = 0.003). Phylogenetic analysis of ZP3 haplotypes revealed that the more southern haplotypes appear to be ancestral, with the northern haplotype evolving more recently, potentially in response to a novel selective pressure as Pacific cod recolonized northern latitudes after glaciation. The sharp break in haplotype frequencies suggests strong selective pressures are operating on small spatial scales and illustrates that selection can create high divergence even in marine species with ample opportunities for gene flow.
Plastic responses of survival and fertility following heat stress in pupal and adultDrosophila virilis
Authors: Walsh Benjamin S. , Parratt Steven R. , Mannion Natasha L. M. , Snook Rhonda R. , Bretman Amanda , Price Tom A. R.
Published: December 2021

The impact of rising global temperatures on survival and reproduction is putting many species at risk of extinction. In particular, it has recently been shown that thermal effects on reproduction, especially limits to male fertility, can underpin species distributions in insects. However, the physiological factors influencing fertility at high temperatures are poorly understood. Key factors that affect somatic thermal tolerance such as hardening, the ability to phenotypically increase thermal tolerance after a mild heat shock, and the differential impact of temperature on different life stages are largely unexplored for thermal fertility tolerance. Here, we examine the impact of high temperatures on male fertility in the cosmopolitan fruit flyDrosophila virilis. We first determined whether temperature stress at either the pupal or adult life history stage impacts fertility. We then tested the capacity for heat‐hardening to mitigate heat‐induced sterility. We found that thermal stress reduces fertility in different ways in pupae and adults. Pupal heat stress delays sexual maturity, whereas males heated as adults can reproduce initially following heat stress, but become sterile within seven days. We also found evidence that while heat‐hardening inD.viriliscan improve high temperature survival, there is no significant protective impact of this same hardening treatment on fertility. These results suggest that males may be unable to prevent the costs of high temperature stress on fertility through heat‐hardening, which limits a species’ ability to quickly and effectively reduce fertility loss in the face of short‐term high temperature events.
Effects of roots systems on hydrological connectivity below the soil surface in the Yellow River Delta wetland
Authors: Zhang Yinghu , Jiang Jiang , Zhang Jinchi , Zhang Zhenming , Zhang Mingxiang
Published: December 2021

In this study, a new method based on field dye‐tracing experiments was used to assess hydrological connectivity below the soil surface. In this method, Phragmites australis in the Yellow River Delta wetland was considered to characterize the interaction between roots systems and hydrological connectivity. The results showed that index of hydrological connectivity (IHC) declined non‐linearly with depth below the soil surface. Roots systems of P. australis were mostly distributed in soils of 0–30 cm. Roots systems parameters (root length, root width, root surface area, root projected area, root volume and root biomass) were positively correlated with IHC. Coarse roots systems (3 < D < 5 mm) made the highest contribution to the changes of IHC. This study provided suggestions for wetland management in the study area: (1) Reeds should not be reaped every year to promote the litters decomposition for roots nutrition availability; and (2) freshwater inputs should be strengthened in the initial/middle growth stage of reeds to improve roots architecture. Knowledge about the interaction between roots systems and hydrological connectivity below the soil surface is crucial for large‐scale wetland protection as wetland managers regulate the control and distribution of vegetation.
Risk factors for asymptomatic echocardiographic abnormalities that predict symptomatic heart failure
Authors: Coller Jennifer M. , Gong Fei Fei , McGrady Michele , Shiel Louise , Liew Danny , Stewart Simon , Owen Alice J. , Krum Henry , Reid Christopher M. , Prior David L. , Campbell Duncan J.
Published: December 2021

Aims

Risk factors for asymptomatic echocardiographic abnormalities that predict symptomatic heart failure (HF) may provide insight into early mechanisms of HF pathogenesis. We examined risk factors associated with asymptomatic echocardiographic structural, systolic, and diastolic abnormalities, separately and in combination, and interactions between risk factors, in the prospective community‐based SCReening Evaluation of the Evolution of New HF (SCREEN‐HF) Study cohort of 3190 participants at increased risk of cardiovascular disease.

Methods and results

Inclusion criteria were age ≥ 60 years with one or more of hypertension, diabetes, ischaemic heart disease, valvular heart disease, abnormal heart rhythm, cerebrovascular disease, or renal impairment. Exclusion criteria were known HF, ejection fraction < 50%, or >mild valve abnormality. Structural, systolic, and diastolic echocardiographic abnormalities were defined according to the Atherosclerosis Risk in Communities study criteria, and risk factors for asymptomatic structural, systolic, and diastolic abnormalities were identified using logistic regression analysis. In multivariable analysis, increased body mass index (BMI), non‐steroidal anti‐inflammatory drug therapy, and alcohol intake were risk factors for isolated structural abnormality, whereas male gender, increased heart rate, atrial fibrillation (AF), angiotensin‐converting enzyme inhibitor therapy, and obstructive sleep apnoea were associated with a lower risk. Moreover, male gender, smoking, increased systolic blood pressure, and physical inactivity were risk factors for isolated systolic abnormality, whereas increased pulse pressure and antihypertensive therapy were associated with a lower risk. Furthermore, increased age, blood pressure, amino‐terminal pro‐B‐type natriuretic peptide level, and warfarin therapy (associated with AF) were risk factors for isolated diastolic abnormality, whereas increased heart rate and triglyceride level (associated with BMI) were associated with a lower risk. The association of increased heart rate with lower risk of structural and diastolic abnormalities was independent of β‐blocker therapy. Interactions between risk factors differed for structural, systolic, and diastolic abnormalities.

Conclusions

The different risk factors for asymptomatic structural, systolic, and diastolic abnormalities that predict symptomatic HF, and the interactions between risk factors, illustrate how these structural, systolic, and diastolic abnormalities represent unique trajectories that lead to symptomatic HF. Improved understanding of these trajectories may assist in the design of HF prevention strategies.
Template Synthesis of Novel Norcorrole Complexes with a Phenyl‐substituted Phosphorus Center
Authors: Jun‐i Yuta , Mizuhata Yoshiyuki , Tokitoh Norihiro
Published: December 2021

Novel norcorroles complexes with a phenyl‐substituted phosphorus center were synthesized by a template method and characterized by NMR spectroscopy and X‐ray single crystal diffraction. It was proved that these new norcorrole phosphorus complexes have aromaticity similar to the very recently reported norcorrole complex with a methoxy‐substituted phosphorus center. This aromaticity results from the peripheral 18π‐system consisting of two methine carbons and four amine‐type pyrrole units with formally pentavalent phosphorus center. On the other hand, these phenyl‐substituted phosphorus complexes showed quite characteristic and strong Q‐band derived from less symmetricity of the molecules than other porphyrinoids.