bluuebunny/crossref_metadata_2025 huggingface dataset:
Insight into the Alkaline Stability of N‐Heterocyclic Ammonium Groups for Anion‐Exchange Polyelectrolytes
Authors: Chen Nanjun , Jin Yiqi , Liu Haijun , Hu Chuan , Wu Bo , Xu Shaoyi , Li Hui , Fan Jiantao , Lee Young Moo
Published: June 2021

The alkaline stability of N‐heterocyclic ammonium (NHA) groups is a critical topic in anion‐exchange membranes (AEMs) and AEM fuel cells (AEMFCs). Here, we report a systematic study on the alkaline stability of 24 representative NHA groups at different hydration numbers (λ) at 80 °C. The results elucidate that γ‐substituted NHAs containing electron‐donating groups display superior alkaline stability, while electron‐withdrawing substituents are detrimental to durable NHAs. Density‐functional‐theory calculations and experimental results suggest that nucleophilic substitution is the dominant degradation pathway in NHAs, while Hofmann elimination is the primary degradation pathway for NHA‐based AEMs. Different degradation pathways determine the alkaline stability of NHAs or NHA‐based AEMs. AEMFC durability (from 1 A cm−2 to 3 A cm−2) suggests that NHA‐based AEMs are mainly subjected to Hofmann elimination under 1 A cm−2 current density for 1000 h, providing insights into the relationship between current density, λ value, and durability of NHA‐based AEMs.
A Chemistry and Microstructure Perspective on Ion‐Conducting Membranes for Redox Flow Batteries
Authors: Xiong Ping , Zhang Leyuan , Chen Yuyue , Peng Sangshan , Yu Guihua
Published: June 2021

Redox flow batteries (RFBs) are among the most promising grid‐scale energy storage technologies. However, the development of RFBs with high round‐trip efficiency, high rate capability, and long cycle life for practical applications is highly restricted by the lack of appropriate ion‐conducting membranes. Promising RFB membranes should separate positive and negative species completely and conduct balancing ions smoothly. Specific systems must meet additional requirements, such as high chemical stability in corrosive electrolytes, good resistance to organic solvents in nonaqueous systems, and excellent mechanical strength and flexibility. These rigorous requirements put high demands on the membrane design, essentially the chemistry and microstructure associated with ion transport channels. In this Review, we summarize the design rationale of recently reported RFB membranes at the molecular level, with an emphasis on new chemistry, novel microstructures, and innovative fabrication strategies. Future challenges and potential research opportunities within this field are also discussed.
An Organic–Inorganic Perovskitoid with Zwitterion Cysteamine Linker and its Crystal–Crystal Transformation to Ruddlesden‐Popper Phase
Authors: Kour Prachi , Chenna Reddy Mallu , Pal Shiv , Sidhik Siraj , Das Tisita , Pandey Padmini , Mukherjee Shatabdi Porel , Chakraborty Sudip , Mohite Aditya D. , Ogale Satishchandra
Published: June 2021

We demonstrate synthesis of a new low‐D hybrid perovskitoid (a perovskite‐like hybrid halide structure, yellow crystals, P21/n space group) using zwitterion cysteamine (2‐aminoethanethiol) linker, and its remarkable molecular diffusion‐controlled crystal‐to‐crystal transformation to Ruddlesden‐Popper phase (Red crystals, Pnma space group). Our stable intermediate perovskitoid distinctly differs from all previous reports by way of a unique staggered arrangement of holes in the puckered 2D configuration with a face‐sharing connection between the corrugated‐1D double chains. The PL intensity for the yellow phase is 5 orders higher as compared to the red phase and the corresponding average lifetime is also fairly long (143 ns). First principles DFT calculations conform very well with the experimental band gap data. We demonstrate applicability of the new perovskitoid yellow phase as an excellent active layer in a self‐powered photodetector and for selective detection of Ni2+ via On‐Off‐On photoluminescence (PL) based on its composite with few‐layer black phosphorous.
Programmable Chromism and Photoluminescence of Spiropyran‐Based Liquid Crystalline Polymer with Tunable Glass Transition Temperature
Authors: Hu Wei , Sun Chang , Ren Yunxiao , Qin Shengyu , Shao Yu , Zhang Lanying , Wu Yu , Wang Qian , Yang Huai , Yang Dengke
Published: June 2021

Spiropyran‐based materials (SPBMs) can give responses to the stimulations induced by the light, heat, force, or pH, which have been used as triggers for many smart materials. Here, a cross‐linkable SPBM containing mesogenic‐units is synthesized, which is pale‐colored, non‐photoluminescent and non‐mesogenic at a spiro form, but dark‐colored, photoluminescent, and mesogenic at a merocyanine form. Moreover, the dynamic interconversion behavior of the form in the different chemical environments are distinct. Liquid crystalline polymers (LCPs) containing the SPBMs cross‐linked via visible light, own a photoswitchable glass transition temperature (Tg) and retain the switchable property; however, the SPBMs cross‐linked via UV light will be locked at the MC state, because the molecular movement was frozen at the room temperature lower than the given Tg of the LCP. Thus, programmable chromism and photoluminescence based on the tunable Tg can be endowed to the functional materials prepared from the SPBMs.
Ein zur Basenkatalyse befähigtes Ligationsauxiliar ermöglicht die cysteinfreie native chemische Ligation an anspruchsvollen Verknüpfungsstellen
Authors: Fuchs Olaf , Trunschke Sebastian , Hanebrink Hendrik , Reimann Marc , Seitz Oliver
Published: June 2021

Ligationsauxiliare werden in der chemischen Proteinsynthese eingesetzt, um den Anwendungsbereich der nativen chemischen Ligation (NCL) über Cystein hinaus zu erweitern. An sterisch anspruchsvollen Ligationsstellen erweisen sich Auxiliar‐vermittelte Ligationen allerdings als schwierig. Oft akkumuliert das im Thiolaustauschschritt der NCL gebildete Thioester‐Intermediat, da der anschließende S→N‐Acyltransfer nur sehr langsam abläuft. In dieser Arbeit stellen wir die 2‐Mercapto‐2‐(pyridin‐2‐yl)ethyl (MPyE)‐Gruppe als das erste Auxiliar vor, welches in der Lage ist, die Ligationsreaktion durch interne Katalyse zu unterstützen. Bemerkenswerterweise liefert das MPyE‐Auxiliar auch dann nützliche Reaktionsraten, wenn Prolin oder eine β‐verzweigte Aminosäure an der Verknüpfung beteiligt sind. Quantenchemische Rechnungen deuten darauf hin, dass der Pyridin‐Stickstoff im geschwindigkeitsbestimmenden Protonentransferschritt als eine intramolekulare Base agiert. Das Auxiliar wird in nur zwei Schritten hergestellt und durch reduktive Alkylierung in das Peptid eingeführt. Die Abspaltung des Auxiliars erfolgt durch Behandlung mit TCEP/Morpholin in Gegenwart eines MnII‐Komplexes als Radikalstarter. Die Synthese eines de novo designten 99mer‐Peptids und eines 80 Aminosäuren langen MUC1‐Peptids demonstrieren die Nützlichkeit des MPyE‐Auxiliars.
Ein vielseitiges Silber(I)‐pentafluorooxosulfat‐Reagenz für die Synthese von OSF5‐Verbindungen
Authors: Haupt Axel , Duvinage Daniel , Lork Enno , Ponomarenko Maksym , Röschenthaler Gerd‐Volker
Published: June 2021

Hiermit berichten wir über die Herstellung von Silber(I)‐pentafluorooxosulfat aus kommerziell erhältlichem AgF und OSF4. Die Verbindung ist überraschend stabil in MeCN‐Lösungen. Darüber hinaus lässt sie sich durch Zugabe von 2,2′‐Bipyridin‐Liganden stabilisieren. Ausgehend von Lösungen des Silber(I)‐Salzes wurden OSF5‐Komplexe mit NiII‐, CuI‐ und CuII‐Zentren erhalten. Weiterhin konnte gezeigt werden, dass AgOSF5 grundsätzlich in der Lage ist, den Transfer von OSF5‐Gruppen an Arine zu vermitteln und somit eine neue und sichere Methode zur Herstellung OSF5‐substituierter Aromaten zu eröffnen. Die Röntgenstrukturanalyse ausgewählter Übergangsmetall‐OSF5‐Verbindungen offenbarte verzerrt oktaedrische [OSF5]−‐Anionen, die durch eine Vielzahl an Wasserstoffbrücken stabilisiert sind.
The Hydrates of TEMPO: Water Vibrations Reveal Radical Microsolvation
Authors: Brás Elisa M. , Fischer Taija L. , Suhm Martin A.
Published: June 2021

An organic radical monohydrate complex is detected in vacuum isolation at low temperature by FTIR supersonic jet spectroscopy for the first time. It is shown to exhibit a rich conformational and vibrational coupling dynamics, which can be drastically reduced by appropriate isotope substitution. Its detection with a new gas recycling infrared spectrometer demonstrates the thermal metastability of the gaseous TEMPO radical even under humid gas conditions. Compared to its almost isoelectronic and isostructural, closed shell ketone analogue, the hydrogen bond of the solvating water is found to be less directional, but stronger and more strongly downshifting the bonded water OH stretch vibration. A second solvent water directs the first one into a metastable hydrogen bond position to solvate the nitrogen center and the first water at the same time.
Electro‐mediated PhotoRedox Catalysis for Selective C(sp3)–O Cleavages of Phosphinated Alcohols to Carbanions
Authors: Tian Xianhai , Karl Tobias A. , Reiter Sebastian , Yakubov Shahboz , de Vivie‐Riedle Regina , König Burkhard , Barham Joshua P.
Published: June 2021

We report a novel example of electro‐mediated photoredox catalysis (e‐PRC) in the reductive cleavage of C(sp3)−O bonds of phosphinated alcohols to alkyl carbanions. As well as deoxygenations, olefinations are reported which are E‐selective and can be made Z‐selective in a tandem reduction/photosensitization process where both steps are photoelectrochemically promoted. Spectroscopy, computation, and catalyst structural variations reveal that our new naphthalene monoimide‐type catalyst allows for an intimate dispersive precomplexation of its radical anion form with the phosphinate substrate, facilitating a reactivity‐determining C(sp3)−O cleavage. Surprisingly and in contrast to previously reported photoexcited radical anion chemistries, our conditions tolerate aryl chlorides/bromides and do not give rise to Birch‐type reductions.
Nanoscale Analysis of Historical Paintings by Means of O‐PTIR Spectroscopy: The Identification of the Organic Particles in L′Arlésienne (Portrait of Madame Ginoux) by Van Gogh
Authors: Beltran Victoria , Marchetti Andrea , Nuyts Gert , Leeuwestein Margje , Sandt Christophe , Borondics Ferenc , De Wael Karolien
Published: June 2021

Optical‐photothermal infrared (O‐PTIR) spectroscopy is a recently developed technique that provides spectra comparable to traditional transmission FTIR spectroscopy with nanometric spatial resolution. Hence, O‐PTIR is a promising candidate for the analysis of historical paintings, as well as other cultural heritage objects, but its potential has not yet been evaluated. This work presents the first application of O‐PTIR to the analysis of cultural heritage, and in particular to an extremely small fragment from Van Gogh's painting L′Arlésienne (portrait of Madame Ginoux). The striking results obtained, including the detection of geranium lake pigments as well as the complete analysis of the stratigraphy, failed with other state‐of‐the‐art techniques, highlight the potential of this method. The integration of O‐PTIR to the study of cultural heritage opens to the possibility of decreasing the amount of sample extracted, therefore contributing to the preservation of the integrity of artworks while providing a complete characterization of the materials.
A Versatile Silver(I) Pentafluorooxosulfate Reagent for the Synthesis of OSF5 Compounds
Authors: Haupt Axel , Duvinage Daniel , Lork Enno , Ponomarenko Maksym , Röschenthaler Gerd‐Volker
Published: June 2021

Herein, we report the preparation of silver(I) pentafluorooxosulfate from commercially available AgF and OSF4. The compound is surprisingly stable in a MeCN solution. Apart from that, AgOSF5 has been stabilised by the addition of 2,2′‐bipyridine ligands. Starting from solutions of the unstabilised silver(I) salt, OSF5 complexes with NiII, CuI, and CuII‐centres have been obtained. In addition, AgOSF5 has proven to be generally capable of mediating the transfer of OSF5 groups to aryne moieties, thus furnishing a new and safe method for the preparation of OSF5‐substituted arenes. X‐ray crystal structure analysis of selected transition‐metal OSF5 compounds have revealed distorted octahedral [OSF5]− anions which are extensively stabilised by hydrogen bonding.
Porous 2D and 3D Covalent Organic Frameworks with Dimensionality‐Dependent Photocatalytic Activity in Promoting Radical Ring‐Opening Polymerization
Authors: Wang Kaixuan , Kang Xing , Yuan Chen , Han Xing , Liu Yan , Cui Yong
Published: June 2021

Dimensionality is a fundamental parameter to modulate the properties of solid materials by tuning electronic structures. Covalent organic frameworks (COFs) are a prominent class of porous crystalline materials, but the study of dimensional dependence on their physicochemical properties is still lacking. Herein we illustrate photocatalytic performances of N,N‐diaryl dihydrophenazine (PN)‐based COFs are heavily dependent on the structural dimensionality. Six isostructural imine‐bonded 2D‐PN COFs and one 3D‐PN COF were prepared. All can be heterogeneous photocatalysts to promote radical ring‐opening polymerization of vinylcyclopropanes (VCPs), which typically produces polymers with a combination of linear (l) and cyclic (c) repeat units. The 2D‐PN COFs have much higher catalytic activity than the 3D‐PN COF, allowing the efficient synthesis of poly(VCPs) with controlled molecular weight, low dispersity and high l/c selectivity (up to 97 %). The improved performance can be ascribed to the 2D structure which has a larger internal surface area, more catalytically active sites, higher photosensitizing ability and photoinduced electron transfer efficiency.
Experimental study on bituminous coal blending in a down‐fired boiler with anthracite combustion system under low load
Authors: Yang Xigang , Chen Guoqing , Huang Linbin , Gu Shijun , Li Changsong , Zhang Yong , Jin Baosheng
Published: June 2021

The industrial experiments were carried out to study the bituminous coal blending in a 660‐MWe supercritical down‐fired boiler with anthracite combustion system under low load. The influence of the bituminous coal ratio on the boiler thermal efficiency, flue gas temperature, flue gas species, and heat transfer of various heating surfaces was analyzed in detail. The ignition distances of three experimental coals were measured, and the influence mechanism of bituminous coal blending on the combustion, heat transfer, and NOx emission in the furnace was proposed. The results show that increasing the bituminous coal blending ratio is beneficial to reduce NOx emissions. However, it leads to the rise of the exhaust gas temperature and the decrease of the boiler efficiency, which can be ascribed to the large amount of the cold primary air sent into the pulverizing system to control the air pulverized coal flow temperature at the mill outlet. The ignition distances of three experimental coals are different. The ignition distance from short to long follows the following order, that is, bituminous coal, lean coal, and anthracite. The earlier ignition of the bituminous coal leads to a sharp rise in the temperature of the airflow at the burner nozzle outlet, a rapid expansion of the airflow volume, and a sharp attenuation of the airflow rigidity, resulting in a short flame downward penetration depth and the upward movement of the flame center in the furnace. As the bituminous coal is blended, the change of the flame center and the flame fullness in the furnace affects the flue gas temperature distribution. Similarly, the change of the radiant heat transfer intensity and the convective heat transfer intensity affects the heat absorption distribution of the heating surface in the furnace.
Phase IIa Global Study Evaluating Rituximab for the Treatment of Pediatric Patients With Granulomatosis With Polyangiitis or Microscopic Polyangiitis
Authors: Brogan Paul , Yeung Rae S. M. , Cleary Gavin , Rangaraj Satyapal , Kasapcopur Ozgur , Hersh Aimee O. , Li Suzanne , Paripovic Dusan , Schikler Kenneth , Zeft Andrew , Bracaglia Claudia , Eleftheriou Despina , Pordeli Pooneh , Melega Simone , Jamois Candice , Gaudreault Jacques , Michalska Margaret , Brunetta Paul , Cooper Jennifer C. , Lehane Patricia B. ,   the PePRS Study Group
Published: June 2021

Objective

To assess the safety, tolerability, pharmacokinetics, and efficacy of rituximab (RTX) in pediatric patients with granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA).

Methods

The Pediatric Polyangiitis Rituximab Study was a phase IIa, international, open‐label, single‐arm study. During the initial 6‐month remission‐induction phase, patients received intravenous infusions of RTX (375 mg/m2 body surface area) and glucocorticoids once per week for 4 weeks. During the follow‐up period, patients could receive further treatment, including RTX, for GPA or MPA. The safety, pharmacokinetics, pharmacodynamics, and exploratory efficacy outcomes with RTX were evaluated.

Results

Twenty‐five pediatric patients with new‐onset or relapsing disease were enrolled at 11 centers (19 with GPA [76%] and 6 with MPA [24%]). The median age was 14 years (range 6–17 years). All patients completed the remission‐induction phase. During the overall study period (≤4.5 years), patients received between 4 and 28 infusions of RTX. All patients experienced ≥1 adverse event (AE), mostly grade 1 or grade 2 primarily infusion‐related reactions. Seven patients experienced 10 serious AEs, and 17 patients experienced 31 infection‐related AEs. No deaths were reported. RTX clearance correlated with body surface area. The body surface area–adjusted RTX dosing regimen resulted in similar exposure in both pediatric and adult patients with GPA or MPA. Remission, according to the Pediatric Vasculitis Activity Score, was achieved in 56%, 92%, and 100% of patients by months 6, 12, and 18, respectively.

Conclusion

In pediatric patients with GPA or MPA, RTX is well tolerated and effective, with an overall safety profile comparable to that observed in adult patients with GPA or MPA who receive treatment with RTX. RTX is associated with a positive risk/benefit profile in pediatric patients with active GPA or MPA.
Characterization of Chinese hamster ovary cell culture feed media precipitate
Authors: Hoang Duc , Galbraith Shaun , Kuang Bingyu , Johnson Amy , Yoon Seongkyu
Published: June 2021

Process intensification of monoclonal antibody production is leading to more concentrated feed media causing issues with precipitation of solids from the media solution. This results in processing problems since components in the precipitate are no longer in solution, changing the media composition and leading to variability in cell culture performance. The goal of this work is to characterize the feed media precipitate, and in particular to identify the precipitated components so that mitigation strategies can be developed. From the conducted analysis, the precipitate was predominately found to be organic and was analyzed with liquid chromatography‐mass spectrometry and inductively coupled plasma‐optical emission spectroscopy (ICP‐OES) to identify the constituent components. Up to ten amino acids were identified with tyrosine (approximately 77 wt.%) and phenylalanine (approximately 4 wt.%) being the most prevalent amino acids. Elemental analysis with ICP‐OES revealed that inorganic components were accounted for less than one weight percentage of the solid precipitate with metal sulfates being the predominant inorganic components.
A mixed‐methods study of cyclin‐dependent kinase 4 and 6 inhibitor symptom burden and quality of life among metastatic breast cancer patients and providers
Authors: Oswald Laura B. , Arredondo Brandy , Kadono Mika , Martinez‐Tyson Dinorah , Meade Cathy D. , Penedo Frank , Antoni Michael H. , Soliman Hatem , Costa Ricardo L. B. , Jim Heather S. L.
Published: June 2021

Background

Cyclin‐dependent kinase 4 and 6 (CDK4/6) inhibitor targeted therapies dramatically improve survival outcomes for metastatic breast cancer (MBC), but they are associated with significant symptom burden that can impact patients’ health‐related quality of life (HRQOL) and treatment outcomes. This study is the first to describe CDK4/6 inhibitor symptoms from the lived perspectives of MBC patients taking CDK4/6 inhibitors and healthcare providers involved in MBC care. This study also explored patients’ symptom management and HRQOL concerns, and gathered feedback about developing supportive interventions for MBC.

Methods

MBC patients taking CDK4/6 inhibitors (N = 20) and MBC healthcare providers (N = 12) participated in semi‐structured interviews that were analyzed for qualitative themes. MBC patients completed surveys about HRQOL, symptoms, and unmet needs.

Results

Patient and provider perceptions of CDK4/6 inhibitor symptoms did not align with patients perceiving symptoms as more burdensome. Patients reported that supportive resources (e.g., support groups, blogs) that are not specific to MBC do not adequately meet their needs. Patients and providers were enthusiastic about developing supportive interventions specifically for MBC and offered considerations for designing such interventions.

Conclusions

Findings highlight differences in perceptions of CDK4/6 inhibitor symptom burden between MBC patients and providers. Results will inform the development of supportive interventions to assist MBC patients in managing CDK4/6 inhibitor symptom burden and maintaining HRQOL. Such interventions could also improve treatment outcomes.
A rare case of bilateral double incisors; Early orthodontic management
Authors: Yassaei Soghra , Sharifi Mohadeseh , Ebrahiminik Zahra
Published: June 2021

A safe and suitable approach in the treatment of unusual malformed anterior maxillary teeth would be to accept a birooted fused incisor as two central teeth by moving it across the midpalatal suture and improve the frontal esthetics.
A fast‐growing schwannoma of the tongue in a 15‐year‐old Iranian male: Review of literature and case report
Authors: Agha‐Hosseini Farzaneh , Moosavi Mahdieh‐Sadat , Aminishakib Pouyan , Yousefian Marzieh
Published: June 2021

Schwannoma can be included in the list of differential diagnoses of tongue masses but seems to be a rare finding in the Iranian population. The current case was presented as an exophytic nodular sessile mass which was growing fast.
Idiopathic intracranial hypertension with juvenile idiopathic arthritis‐associated uveitis: A case report
Authors: Alkoht Asaad , Alhariry Huda , Hanafi Ibrahem , Aboud Majed
Published: June 2021

A 14‐year‐old girl with juvenile idiopathic arthritis (JIA)‐associated uveitis who also had optic disc edema, was later diagnosed with Idiopathic intracranial hypertension (IIH). To our knowledge, this is the fifth case of the coexistence of uveitis and IIH among children, and the only one with no obvious risk factors for IIH.
Sudden rupture of small aneurysm of the radial artery in a patient with COVID‐19 pneumonia
Authors: Mazzaccaro Daniela , Giannetta Matteo , Malacrida Giovanni , Zilio Dino , Modafferi Alfredo , Righini Paolo , Marrocco‐Trischitta Massimiliano M. , Vaienti Luca , Nano Giovanni
Published: June 2021

In patients with COVID‐19, even small radial aneurysm may suddenly rupture.
Diagnostics of Torsade de Pointes in an oncohematology patient: A case report
Authors: Bilmakhanbetova Ainur , Zhakhina Gulnur , Beisenbay Meruyert , Marat Daulet
Published: June 2021

Complex heart rhythm disturbances due to cardiotoxicity may not be identified in time, and this may have an unfavorable outcome for patients. Holter monitoring can be a solution to prevent sudden cardiac death of oncohematology patients.
Dohsa‐hou intervention for reciprocal interpersonal interaction for a girl with Kabuki syndrome and autism spectrum disorder
Authors: Kawano Juri , Fujino Haruo
Published: June 2021

Although available evidence for psychosocial treatment for patients with Kabuki syndrome is limited, Dohsa‐hou, a psychomotor therapy, could be a treatment option for autism spectrum disorder associated with the disorder.
Successful management of therapy‐related chronic myelomonocytic leukemia with cytarabine, aclarubicin, and azacitidine following tegafur/gimeracil/oteracil
Authors: Nakako Soichiro , Takakuwa Teruhito , Ichimura Hirona , Okamura Hiroshi , Nanno Satoru , Nishimoto Mitsutaka , Nakashima Yasuhiro , Koh Hideo , Hino Masayuki , Nakamae Hirohisa
Published: June 2021

A 55‐year‐old man was diagnosed with therapy‐related chronic myelomonocytic leukemia (t‐CMML) after exposure to tegafur/gimeracil/oteracil. Although he was refractory to hydroxyurea and low‐dose cytarabine, combination therapy with cytarabine, aclarubicin and azacitidine (CA‐AZA) provided good disease control, and he underwent allogeneic stem cell transplantation. This report has two key massages. First, tegafur/gimeracil/oteracil may have a potential risk of developing t‐CMML. Second, CA‐AZA therapy may be considered as a therapeutic option for patients with t‐CMML.
May‐Thurner syndrome: A cause of unexplained unilateral leg edema
Authors: Tago Masaki , Fujiwara Motoshi , Tokushima Yoshinori , Yamashita Shun , Aihara Hidetoshi
Published: June 2021

Physicians should be familiar with May‐Thurner syndrome, characterized by the compression of the left common iliac vein by the right common iliac artery and the vertebral body, resulting in pain and swelling of the left lower extremity and DVT. A 64‐year‐old woman presented with unexplained edema in the left lower extremity. Computed tomography with contrast enhancement revealed that the left common iliac vein was compressed and narrowed by the right common iliac artery and the vertebral body, leading to the diagnosis of May‐Thurner syndrome.
Mixed fibrolamellar hepatocellular carcinoma
Authors: Limaiem Faten , Bouraoui Saadia
Published: June 2021

Pure and mixed fibrolamellar hepatocellular carcinomas display distinct clinical presentations and epigenetic backgrounds leading to different prognoses and as such may be regarded as separate clinical entities.
Twenty years' use of expanded polytetrafluoroethylene sheet for an artificial cardiac pacemaker
Authors: Yorita Kenji , Takahashi Junichi , Tano Kazutoshi , Ichikawa Yoichi , Hamaguchi Nobumasa , Yasui Wataru
Published: June 2021

Physicians can prolongedly use expanded polytetrafluoroethylene sheets for fixation of artificial cardiac pacemakers to avoid pacemaker lead displacement. The sheets can also be used to prevent implant rejection in patients with metal allergies.
Tension pneumothorax complicating COVID‐19 pneumonia
Authors: Mohamed Amr
Published: June 2021

To emphasize the importance of lung imaging in a patient with acute decompensation in the setting of COVID‐19 and to know that pneumothorax is currently a well‐recognized complication related to COVID‐19 pneumonia.
A rare cause of multiple liver masses
Authors: Mizukoshi Kenta , Yoshikawa Takaaki , Ohana Masaya
Published: June 2021

Primary hepatic mucosa‐associated lymphoid tissue (MALT) lymphoma is a rare disease. However, if atypical hepatic masses are observed, hepatic MALT lymphoma should be considered in the differential.
Re‐exposure to immunotherapy in metastatic colon cancer: A case report
Authors: Hamre Tonje Riise , Stougaard Julie Kristine , Havelund Birgitte Mayland , Jensen Lars Henrik , Hansen Torben Frøstrup
Published: June 2021

Re‐exposure to immunotherapy in metastatic colorectal cancer may be indicated in selected patients that previously benefitted from immunotherapy with tolerable irAEs.
Interactions Between Two Cobalt Salen Centers Bridged by Non‐Conjugated Linkers**
Authors: Speiser Bernd , Zitzer Georg
Published: June 2021

Tetra‐tert‐butyl‐Co(salen), an amido‐substituted derivative and a series of bis(salen) complexes of cobalt(II) with the two metal centers bridged by flexible, non‐conjugated bis‐amido linkers are investigated by cyclic voltammetry, chronoamperometry, and differential pulse voltammetry in four electrolytes (acetonitrile or dichloromethane, conventional or weakly coordinating anion). Cyclic voltammograms are analyzed by simulation based on E or EE mechanisms. The compounds are characterized by formal potentials
, diffusion coefficients D and number of electrons transferred, n. Differences in the
values for the subsequent two one‐electron transfer steps are used as indicators for the interaction between the metal centers in the bis(salen) complexes. The effects of solvent and supporting electrolyte are consistent with the assumption of electrostatic through‐space interactions and coordination to the Co centers. In the dinuclear complexes step‐wise electron transfers according to normal potential ordering makes these compounds “pretenders” in Winter's terms (R.F. Winter, Organometallics 2014, 33, 4517–4536).
Application of the Redox‐Transmetalation Procedure to Access Divalent Lanthanide and Alkaline‐Earth NHC Complexes**
Authors: Schwarz Noah , Sun Xiaofei , Yadav Ravi , Köppe Ralf , Simler Thomas , Roesky Peter W.
Published: June 2021

Divalent lanthanide and alkaline‐earth complexes supported by N‐heterocyclic carbene (NHC) ligands have been accessed by redox‐transmetalation between air‐stable NHC‐AgI complexes and the corresponding metals. By using the small ligand 1,3‐dimethylimidazol‐2‐ylidene (IMe), two series of isostructural complexes were obtained: the tetra‐NHC complexes [LnI2(IMe)4] (Ln=Eu and Sm) and the bis‐NHC complexes [MI2(IMe)2(THF)2] (M=Yb, Ca and Sr). In the former, distortions in the NHC coordination were found to originate from intermolecular repulsions in the solid state. Application of the redox‐transmetalation strategy with the bulkier 1,3‐dimesitylimidazol‐2‐ylidene (IMes) ligand yielded [SrI2(IMes)(THF)3], while using a similar procedure with Ca metal led to [CaI2(THF)4] and uncoordinated IMes. DFT calculations were performed to rationalise the selective formation of the bis‐NHC adduct in [SrI2(IMe)2(THF)2] and the tetra‐NHC adduct in [SmI2(IMe)4]. Since the results in the gas phase point towards preferential formation of the tetra‐NHC complexes for both metal centres, the differences between both arrangements are a result of solid‐state effects such as slightly different packing forces.
Bulky Barbiturates as Non‐Toxic Ionic Dye Insulators for Enhanced Emission in Polymeric Nanoparticles
Authors: Andreiuk Bohdan , Aparin Ilya O. , Reisch Andreas , Klymchenko Andrey S.
Published: June 2021

Bulky hydrophobic counterions (weakly coordinating anions) can insulate ionic dyes against aggregation‐caused quenching (ACQ) and enable preparation of highly fluorescent dye‐loaded nanoparticles (NPs) for bioimaging, biosensing and light harvesting. Here, we introduce a family of hydrophobic anions based on fluorinated C‐acyl barbiturates with delocalized negative charge and bulky non‐polar groups. Similarly to fluorinated tetraphenylborates, these barbiturates prevent ACQ of cationic dye alkyl rhodamine B inside polymer NPs made of biodegradable poly(lactic‐co‐glycolic acid) (PLGA). Their efficiency to prevent ACQ increases for analogues with higher acidity and bulkiness. Their structure controls dye‐dye communication, yielding bright NPs with on/off switching or stable emission. They enhance dye encapsulation inside NPs, allowing intracellular imaging without dye leakage. Compared to fluorinated tetraphenylborates known as cytotoxic transmembrane ion transporters, the barbiturates display a significantly lower cytotoxicity. These chemically available and versatile barbiturate derivatives are promising counterion scaffolds for preparation of bright non‐toxic fluorescent nanomaterials.
Chirality in polythiophenes: A review
Authors: Wang Kun , Xiao Yin
Published: June 2021

Chiroptical polythiophene (PTh), as one of the most important chiral conductive polymers, is an emerging and hot topic in chiral materials, which shows great application potentials in fields as diverse as chiral sensing and separation, asymmetry catalysis, chiroptoelectronics, and even chiro‐spintronics. This review summarizes progress in chiral polythiophenes (PThs) in the past 10 years, including the synthesis, properties and applications. Main focus is placed on the manner in which chirality is implemented and the optical activity of the chiral PThs. We showcase examples in which the chirality of PThs is induced by side chain substituents with point, planar, and axial chirality or arises from external chiral media. Application of chiral PThs is also included. Finally, perspectives for further development are offered.
Management of serious complications in intra‐abdominal desmoid‐type fibromatosis
Authors: Bini Federica , Fiore Marco , Provenzano Salvatore , Bertulli Rossella , Ottini Arianna , Colombo Chiara , Vitellaro Marco , Greco Gabriella , Morosi Carlo , Gronchi Alessandro , Casali Paolo Giovanni , Palassini Elena
Published: June 2021

Background

Desmoid fibromatosis (DF) is a rare and locally infiltrative monoclonal fibroblastic proliferation arising from connective tissues, with lack of metastatic potential. About 10% of all DF cases are intra‐abdominally sited. Complications in this site, due to the locally infiltrative nature of the disease, may be severe and potentially life threatening. However, data on incidence, management, and outcome of these complications are limited.

Aim

Data of patients with sporadic or FAP‐related intra‐abdominal DF treated at Istituto Nazionale dei Tumori (INT) in Milano from 2005 to 2020 who developed a serious complication during the course of their disease were retrospectively collected and analyzed with a descriptive statistics.

Methods and Results

Out of 72 intra‐abdominal DF, 8 cases were identified (M/F: 5/3, median age: 35 years, FAP‐related/sporadic: 2/6): 3 with bowel obstruction, 5 with bowel perforation. In 4 cases the serious complication was the first evidence of disease; in the other 4 cases it occurred at a time interval from diagnosis in the range of 4–44 months (during an active surveillance program in one case and during chemotherapy in the other 3 cases). A surgical treatment was feasible and successful in 5 cases. In 3 surgically unmanageable patients, all progressing and experiencing acute complications while on chemotherapy, a non‐surgical approach with intensive supportive treatment and with a prompt change of chemotherapy regimen was implemented, being successful in two, the other patient dying due to a concomitant progressive lymphoma thereafter.

Conclusion

In this series of intra‐abdominal DF, the incidence of serious complications was 11%. Most patients were successfully treated with surgery. When surgery was deemed to be unfeasible, a conservative management with intensive supportive care and a careful choice of chemotherapy was adopted, ensuring a favorable outcome in most.
Selenophene‐Based Hole‐Transporting Materials for Perovskite Solar Cells
Authors: Illicachi Luis A. , Urieta‐Mora Javier , Momblona Cristina , Molina‐Ontoria Agustín , Calbo Joaquín , Aragó Juan , Insuasty Braulio , Ortiz Alejandro , Ortí Enrique , Martín Nazario , Nazeeruddin Mohammad Khaja
Published: June 2021

Two novel and simple donor‐π‐bridge‐donor (D‐π‐D) hole‐transporting materials (HTMs) containing two units of the p‐methoxytriphenylamine (TPA) electron donor group covalently bridged by means of the 3,4‐dimethoxyselenophene spacer through single and triple bonds are reported. The optoelectronic and thermal properties of the new selenium‐containing HTMs have been determined using standard experimental techniques and theoretical density functional theory (DFT) calculations. The selenium‐based HTMs have been incorporated in mesoporous perovskite solar cells (PSCs) in combination with the triple‐cation perovskite [(FAPbI3)0.87(MAPbBr3)0.13]0.92 [CsPbI3]0.08. Limited values of power conversion efficiencies, up to 13.4 %, in comparison with the archetype spiro‐OMeTAD (17.8 %), were obtained. The reduced efficiencies showed by the new HTMs are attributed to their poor film‐forming ability, which constrains their photovoltaic performance due to the appearance of structural defects (pinholes).
Enhanced Detection of Short‐Chain Fatty Acids Using Gas Chromatography Mass Spectrometry
Authors: Gu Haiwei , Jasbi Paniz , Patterson Jeffrey , Jin Yan
Published: June 2021

Short‐chain fatty acids (SCFAs) are produced mainly by intestinal microbiota and play an important role in many host biological processes such as immune system development, glucose and energy homeostasis, and regulation of immune response and inflammation. In addition, they participate in the regulation of anorectic hormones, which have a role in appetite control, tumor suppression, and regulating the central and peripheral nervous systems. As such, there is great interest in monitoring levels of SCFAs in various biological samples. Due to the highly hydrophilic and volatile characteristics of SCFAs, optimizing extraction and sample preparation procedures is often a central component to further improve SCFA quantification. Here, we describe a rapid and highly sensitive analytical method for measuring SCFAs in human serum and feces. Briefly, SCFAs are protected by adding sodium hydroxide, followed by a one‐step extraction (pH > 7). Then, SCFAs are quantified by gas chromatography coupled to mass spectrometry (GC‐MS) after derivatization with N‐tert‐butyldimethylsilyl‐N‐methyltrifluoroacetamide (MTBSTFA). This method demonstrates excellent sensitivity, linearity, and derivatization efficiency for simultaneous determination of 14 different SCFAs. Further, this validated method can be successfully applied to quantify SCFAs in micro‐scale biological samples. In summary, we describe efficient and advanced sample preparation and detection procedures that are critically needed for monitoring SCFA concentrations in human biological samples. © 2021 Wiley Periodicals LLC.

Basic Protocol: SCFA extraction and detection from fecal and serum samples with gas chromatography−mass spectrometry
CAGE‐prox: A Unified Approach for Time‐Resolved Protein Activation in Living Systems
Authors: Wang Jie , Liu Yuan , Liu Yanjun , Wang Chu , Chen Peng R.
Published: June 2021

Temporal activation of proteins of interest (POIs) offers a gain‐of‐function approach to investigate protein functions in dynamic biological processes. Fusion of photo/chemical‐switchable proteins to a POI, or site‐specific blockage/decaging of catalytic residue(s) on a POI, are the most widely utilized strategies for selective protein activation. These methods, however, either lack generality (e.g., active site decaging) or would modify the POI with a bulky tag (e.g., genetic fusion). Recently, a computationally aided and genetically encoded proximal decaging strategy (CAGE‐prox) has been developed for time‐resolved photoactivation of a broad range of proteins in living systems. In contrast to the direct decaging of the active site of a POI, CAGE‐prox relies on a unified caged amino acid that can be anchored in proximity to a protein's functional site for temporal blockage of its activity until rescued by photo/chemical decaging. In order to identify the optimal site for photo‐caged unnatural amino acid insertion, which is key for the effective blockade and re‐activation of the POI, a computational algorithm was developed to screen all possible positions in close proximity to the functional site that would enable turning off/on protein activity via caging/decaging operations. Here, we describe the CAGE‐prox strategy, from in silico design to experimental validation, and provide various examples of its application. © 2021 Wiley Periodicals LLC

Basic Protocol 1: In silico design and experimental validation of CAGE‐prox

Basic Protocol 2: Orthogonal activation of a POI by CAGE‐prox while minimizing the activity from the endogenous protein

Basic Protocol 3: CAGE‐prox‐enabled, time‐resolved proteomics for the identification of substrates of a proteolytic enzyme

Basic Protocol 4: Controlled activation of protein‐based prodrugs for tumor therapy
The recent development of thymol derivative as a promising pharmacological scaffold
Authors: Sahoo Chita Ranjan , Paidesetty Sudhir Kumar , Padhy Rabindra Nath
Published: June 2021

Thymol (a phenol ring bearing active phytoconstituent) is a privileged scaffold, which is diversified in natural sources. This scaffold acts as an obligatory template for scheming and arriving at designing some newer drug‐molecules with potential biological activities. In the pharmacological perspective, the promising active sites of the scaffold are the positions C‐1, C‐4, and C‐6 of thymol that would be accountable for developing potent drug candidates. This review aims to explore the various synthetic routes and the structural‐activity relationship of thymol scaffold with suitable active pharmacophore sites.
Are stable isotope ratios suitable for describing niche partitioning and individual specialization?
Authors: Matich Philip , Bizzarro Joseph J. , Shipley Oliver N.
Published: June 2021

As concerns about anthropogenic and natural disturbance grow, understanding animal resource use patterns has been increasingly prioritized to predict how changes in environmental conditions, food web structure, and population dynamics will affect biological resilience. Among the tools used to assess resource use, stable isotope analysis has proliferated in ecological studies, particularly in relation to describing intra‐ and interspecific variation in trophic interactions. Despite a growing need to disseminate scientific information, the inherent limitations of stable isotope ratios and inappropriate synonymizing of distinct evolutionary and ecological processes may mislead ecological inferences in natural systems. This situation necessitates a re‐evaluation of the utility of stable isotope ratios to address certain ecological questions. Here, we assess the efficacy of stable isotope ratios to describe two fundamental ecological processes, niche partitioning and individual specialization. Investigation of these processes has increased substantially in accordance with increased access to stable isotope data. This article discusses the circumstances and approaches that are necessary to evaluate niche partitioning and individual specialization, and outlines key considerations for the associated application of stable isotope ratios.
Multiyear resource enrichment creates persistently higher species diversity in a landscape‐scale field experiment
Authors: Lancaster Jill , Downes Barbara J.
Published: June 2021

Short‐term resource enrichment can increase species diversity in communities, but prolonged resource enrichment may result in either a diversity collapse or persistent high species diversity if fluctuation‐dependent mechanisms of species coexistence are triggered. We tested the effects of resource enrichment on stream invertebrates by boosting densities of benthic detritus. In a 22‐km stream length, we used wooden stakes to enhance retention of detritus at 40‐m‐long sites; other sites acted as controls. Detritus and invertebrates were sampled prior to treatment and then 1, 2, and 5 yr later. Previously, we reported that detrital densities, species diversity, and densities increased at enrichment sites after 12 months. Here we report that similar increases occurred 2 and 5 yr after manipulation. Prolonged resource enrichment produced persistently higher species diversity without loss of any taxa from the species pool, despite strong shifts in faunal composition in response to environmental variation, including a 1‐in‐100‐yr flood. Detritus densities set upper limits to the densities of common taxa. Positive relations between invertebrate and detritus densities (density–resource relationships) took a variety of forms and showed that detritus was an essential resource for some taxa and a substitutable resource for others. Species varied in the minimum amount of detritus required for presence at a site, and population densities increased strongly from low densities when detritus was increased. These outcomes suggest that fluctuation‐dependent mechanisms of coexistence enabled new taxa to coexist at manipulation sites, with relative nonlinear averaging of competition and the storage effect most likely to be in play. Two characteristics of the study stream underpin diversity increases with resource enrichment: overall low background densities of detritus and species that are able to disperse successfully from upstream areas where detritus is more abundant. Thus, the effects of resource enrichment are context dependent.
Quantifying the relationship linking the community‐weighted means of plant traits and soil fertility
Authors: Daou Laurent , Garnier Éric , Shipley Bill
Published: June 2021

Is it possible to generalize relationships between certain plant traits and soil fertility? In particular, are there quantitative relationships between community‐weighted mean (CWM) trait values of leaf dry‐matter content (LDMC), specific leaf area (SLA), plant height, and Grime’s competitor‐stress tolerator‐ruderal (CSR) strategy scores and the generalized soil fertility, FG (i.e., the capacity of a soil to produce biomass when all nonsoil variables are held constant) that are generalizable across different species assemblages and geographical areas? We assessed FG in 21 sites in southern Quebec and 7 sites in southern France using a previously published method based on structural equation modeling. We then determined the CWM values of LDMC, SLA, plant height, and CSR scores in the 21 Quebec sites to obtain quantitative relationships between FG and these CWM traits. Using these relationships, we independently tested the generality of the trait–fertility relationships using data from French sites. The relationships between FG and the CWM traits were nonlinear, but displayed the expected qualitative trends as reported in the literature. In particular, the S score and CWM LDMC decreased with increasing soil fertility, and the R score and CWM SLA increased. CWM traits were more strongly correlated to measures of FG (r2 up to 0.48) than to measures of other soil characteristics (r2 up to 0.17 for nitrogen flux). Importantly, the independently tested French FG–trait relationships showed no significant deviations from these quantitative relationships. Further investigation is necessary to confirm if the same trend applies to other regions and or ecosystems.
Does pulmonary artery pulsatility index predict mortality in pulmonary arterial hypertension?
Authors: Lim Yinghao , Low Ting‐Ting , Chan Siew Pang , Lin Weiqin , Teo Ting Wei , Jang Jin‐Hao Justin , Kuntjoro Ivandito , Tay Edgar Lik‐Wui , Yip James Wei‐Luen
Published: June 2021

Aims

Pulmonary artery pulsatility index (PAPi), defined as [(pulmonary artery systolic pressure − diastolic pulmonary artery pressure)/mean right atrial pressure], is a novel haemodynamic index that predicts right ventricular failure after myocardial infarction and left ventricular assist device implantation. We analysed if a low PAPi is associated with death in our 14 ‐ ​year pulmonary arterial hypertension (PAH) registry.

Methods

Consecutive patients with newly diagnosed PAH and complete haemodynamic data were prospectively enrolled into our standing registry between January 2003 and December 2016. PAPi was calculated from baseline invasive right heart catheterization data. A prognostic cut‐off value was determined with a decision tree. Baseline characteristics of ‘high’ and ‘low’ PAPi groups based on this cut‐off were compared, as well as odds of death and time‐to‐death.

Results

One hundred and two patients were included. Mean age was 53 years, and 77% were women. Our multi‐ethnic cohort was 64% Chinese, 23% Malay, and 10% Indian. The aetiologies were idiopathic (33%), connective tissue disease (31%), congenital heart disease (24%), and others (12%). The low PAPi group (<5.3) had a greater age (56 years vs. 49 years), lower pulmonary artery systolic pressure (71 mmHg vs. 85 mmHg), and higher mean right atrial pressure (14 mmHg vs. 6 mmHg). Mortality risk was higher in the low PAPi group (adjusted odds ratio: 2.98 and adjusted hazard ratio: 2.23). Mean right atrial pressure was the strongest predictor (hazard ratio 1.114, P = 0.009) when components of PAPi were analysed.

Conclusions

Pulmonary artery pulsatility index was found to be predictive of mortality in PAH and may be a valuable marker for risk stratification. Its prognostic strength may be driven by mean right atrial pressure.