bluuebunny/crossref_metadata_2025 huggingface dataset:
Method development and validation of LC–MS/MS‐based assay for the simultaneous quantitation of trastuzumab and pertuzumab in cynomolgus monkey serum and its application in pharmacokinetic study
Authors: Gui Luo‐lan , Li Li , Dong Li‐hou , Xiang Shen‐si , Zhai Jian‐ping , Ge Zhi‐qiang , Song Hai‐feng
Published: May 2020

We present a simple and robust LC–MS/MS assay for the simultaneous quantitation of an antibody cocktail of trastuzumab and pertuzumab in monkey serum. The LC–MS/MS method saved costs, decreased the analysis time, and reduced quantitative times relative to the traditional ligand‐binding assays. The serum samples were digested with trypsin at 50°C for 60 min after methanol precipitation, ammonium bicarbonate denaturation, dithiothreitol reduction, and iodoacetamide alkylation. The tryptic peptides were chromatographically separated using a C18 column (2.1 × 50 mm, 2.6 μm) with mobile phases of 0.1% formic acid in water and acetonitrile. The other monoclonal antibody, infliximab, was used as internal standards to minimize the variability during sample processing and detection. A unique peptide for each monoclonal antibody was simultaneously quantified using LC–MS/MS in the multiple reaction monitoring mode. Calibration curves were linear from 2.0 to 400 μg/mL. The intra‐ and inter‐assay precision (%CV) was within 8.9 and 7.4% (except 10.4 and 15.1% for lower limit of quantitation), respectively, and the accuracy (%Dev) was within ±13.1%. The other validation parameters were evaluated, and all results met the acceptance criteria of the international guiding principles. Finally, the method was successfully applied to a pharmacokinetics study after a single‐dose intravenous drip administration to cynomolgus monkeys.
Risk factors for intracranial infection after craniotomy: A case–control study
Authors: Wang Li‐Yi , Cao Xu‐Hua , Shi Li‐Ke , Ma Zhi‐Zhao , Wang Yue , Liu Yan
Published: May 2020

Background

Intracranial infection, serving as a severe postoperative infection after craniotomy, poses significant problems for patients' outcomes.

Objective

To explore risk factors for intracranial infection after craniotomy.

Methods

A total of 2,174 patients who underwent craniotomy from 1 May 2018 to 30 June 2019 were retrospectively studied. Finally, 196 patients with intracranial infections were classified as case group, and 392 patients randomly selected from patients without intracranial infection were classified as control group. Demographic, clinical, laboratory, microbiological, and antimicrobial data were systemically recorded. The characteristics, pre‐ and postoperative variables, and other variables were evaluated as risk factors for intracranial infection by univariate analysis and binary logistic regression model.

Results

There was no significant difference in terms of demographics between two groups, except for gender, hypertension, length of stay (LOS), intraoperative blood loss, tumor, and trauma surgery. The independent risk factors were male, age ≤45, hypertension, tumor surgery, surgery in autumn (compared with spring), surgical duration ≥4 hr, intraoperative blood loss ≥400 ml, and postoperative oral infection, coma, and serum RBC > normal value. Trauma surgery (p < .001, OR = 0.05, 95% CI: 0.017–0.144) was an independent protective factor (p < .05, OR < 1) for intracranial infection. All 196 patients in the case group submitted specimens for cerebrospinal fluid (CSF) cultures, and 70 (35.71%) patients had positive results. Gram‐positive pathogens predominated (59 cases, 84.28%). Staphylococcus were the most common causative pathogens, and fully resistant to aztreonam, cefazolin, and benzylpenicillin, but not resistant to linezolid and minocycline.

Conclusion

Identifying the risk factors, pathogens, and pathogens' antibiotic resistance for intracranial infection after craniotomy plays an important role in the prognosis of patients.
Determinants of green marketing mix in developing economies: Conceptualisation and scale validation approach
Authors: Mehraj Danish , Qureshi Ishtiaq Hussain
Published: May 2020

Growing environmental issues and rising concerns about sustainable development are rapidly shifting the traditional marketing and forcing organisations to practice green marketing mix. In an attempt to revisit present‐day environmental issues which are related to the industry, this paper provides a glimpse about the nature of green marketing mix in the Indian context. To validate the model, data were collected from 450 firms and was analysed using an appropriate statistical tool. The results identified four factors for green marketing mix scale: (a) Green Solution, (b) Green Information, (c) Green Value and (d) Green Access. The findings contribute to the theory of green marketing concept. The study is expected to provide valuable insights into the green marketing mix for the industry, which can be of immense help to local and global marketers. Further, it provides a wide‐ranging scale for the academic researchers who want to explore the green marketing mix in different organisational settings as a base for future study.
Variability of the maxillary suture maturation and density in the subjects with different sex and growth status
Authors: Betlej Anna , Gandhi Vaibhav , Upadhyay Madhur , Allareddy Veerasathpurush , Tadinada Aditya , Yadav Sumit
Published: May 2020

Introduction

The objective of this study was to classify median palatine suture (MPS) maturation type in young and adult patients. Additionally, we compared MPS maturity type and density based on sex and growth status.

Materials and methods

In this retrospective cone beam computed tomography study, we included a total of 221 subjects, grouped based on sex and growth status. Once scans were aligned and oriented in the sagittal view, we conducted our evaluations on the axial sections. Based on interdigitation and shape, the MPS were categorized into Maturation Types A through E. Additionally, MPS density was measured as Hounsfield unit equivalent pixel intensity value scale for anterior and posterior sutural regions.

Results

The majority of male (39%) and female (42%) subjects had MPS Maturation Type C. A maximum number of growing (42%) patients had Type C and nongrowing subjects (39%) had Type E sutures. The sex comparison showed significantly lower (p < .001) MPS density for both anterior and posterior regions in males when compared to females. Additionally, for the posterior region, nongrowing males had significantly lower (p < .001) MPS density when compared to nongrowing females. Subgroup comparisons of the MPS densities between growing and nongrowing males and growing and nongrowing females showed a significant difference (p < .001).

Conclusion

Classification of the MPS based on the maturation types provides a reliable predictor for orthodontic treatment planning. MPS density is significantly higher in females as compared to males. Similarly, nongrowing individuals have significantly higher MPS density compared to growing individuals for both anterior and posterior locations.
A death in the family: Citizens' experiences of changing healthcare commissioning practices in South East England
Authors: Graber Rebecca , Zoli Anna , Walker Carl , Artaraz Kepa
Published: May 2020

The Brighton Citizens Health Services Survey was an academic activism project to identify and understand citizens' perceptions of and responses to healthcare commissioning practices. Significant legislated changes to the National Health System (NHS) across England have increased marketisation in healthcare provision, yet little research has explored the psychological dimensions of this shifting context and its community impact. Taking a community psychological perspective to social policy, we aimed to understand lay citizens' lived experience of changes in healthcare commissioning and provision. Thematic analysis of 379 free‐text responses yielded two thematic clusters. Cluster 1 describes the lived experience of citizens considering reforms to the NHS, depicting grief, mortality and fear in uncertainty. Cluster 2 explores where these affective responses may derive from by detailing conceptualisations of the NHS in the lived experience, describing how the NHS was experienced as a complex and embodied phenomenological object. Findings suggest people relate affectively to local commissioning practices, feeling a sense of loss when facing the degradation of ‘their’ NHS. We argue that an affective relational perspective centres important questions of silencing, voice‐giving, meaningful engagement and ways of knowing that in turn impact the landscape of community health.
Coronary artery perforation into the upper gastrointestinal cavity due to gastric ulceration
Authors: Yamanaga Kenshi , Sakamoto Kenji , Kajiwara Ichiro , Tsujita Kenichi
Published: May 2020

An 82‐year‐old man who had previously undergone a proximal gastrectomy with jejunal interposition surgery for stomach cancer was transferred to our hospital for massive hematemesis and hypotension. His electrocardiogram showed ST‐segment elevation in lead ΙΙ, ΙΙΙ, aVF, which confirmed inferior myocardial infarction. Due to active hematemesis, upper endoscopy was performed initially. A visible vessel of gastric ulceration was discovered, and hemostasis was achieved using hemoclips. Subsequently, coronary angiography was performed since the right coronary artery (RCA) segment 4 atrioventricular (AV) was occluded. After thrombectomy and intravascular ultrasound (IVUS), 2.0 mm balloon angioplasty was done, and coronary perforation occurred. During coronary angiography, extravasation of the contrast material into the gastrointestinal cavity was noted. A covered stent was placed across segment 3 to segment 4 descending posteriorly (PD) to stop the blood supply to the perforation site of segment 4 AV. After stenting, adequate re‐hemostasis was achieved. The patient was discharged after 28 days. This is the first report of a coronary artery perforation into the gastrointestinal cavity.
Intravascular ultrasound‐guided pulmonary artery embolectomy for saddle pulmonary embolism
Authors: Effoe Valery S. , Kumar Gautam , Sachdeva Rajesh
Published: May 2020

A percutaneous catheter‐directed treatment approach is preferred among patients with acute submassive pulmonary embolism (PE) and chronic kidney disease (CKD), who are at significant risk of bleeding with thrombolytics. Limiting contrast volume in these patients could reduce morbidity and mortality associated with contrast‐induced acute kidney injury (CI‐AKI). We present the case of a 61‐year‐old African American woman (BMI 46.9 kg/m2) with multiple comorbidities, including a PE 3 years prior (not currently on anticoagulation) and CKD (GFR 33 ml/min/1.73/m2), presented to the emergency department with 3 weeks of dyspnea on exertion which worsened 3–5 days preceding her presentation. On examination, she was hemodynamically stable, oxygen saturation was 88% on 5 l, in mild respiratory distress with bilateral lower extremity pitting edema. Troponin was 0.06 ng/ml (ref. <0.04), B‐type natriuretic peptide was 932 pg/ml (ref. ≤78), arterial oxygen partial pressure was 56 (ref. 80–110) and hemoglobin was 10.1 g/dl (ref. 11.3–15.0). Computed tomography pulmonary angiography performed with IV contrast showed a saddle embolus with evidence of right heart strain (RV/LV ratio: 2.05). A transthoracic echocardiogram showed a dilated RV and mean pulmonary artery pressure was 53 mmHg on right heart catheterization. She underwent a successful catheter‐directed pulmonary embolectomy with the aid of an intravascular ultrasound (IVUS) along with fluoroscopy. To prevent CI‐AKI, intravenous contrast was not used for the procedure. To the best of our knowledge, this is the first reported case of an “IVUS‐only” approach in a patient with acute submassive PE and CKD.
Urea Decomposition and Implication for NOx Reduction with Cu‐Zeolite and Vanadia‐Selective Catalytic Reduction
Authors: Wu Yi-Jiang , Wang Fengshuang , Tang Weiyong , Kakwani Ramesh , Hou Yaling , Feng Gang
Published: May 2020

Understanding urea decomposition is critical to achieve highly efficient selective catalytic reduction (SCR). The urea decomposition process in an exhaust pipe and in Cu‐zeolite and vanadia‐SCR (V‐SCR) was studied in engine test cells. The unconverted urea at the SCR inlet can be substantial at lower temperatures. HNCO and NH3 are two dominant products at the SCR inlet. Urea and HNCO continue to decompose in SCR catalysts, with a rate much faster than in the homogeneous stream. The HNCO hydrolysis process is extremely efficient in Cu‐zeolite SCR and the abundant NH3 from urea overdosing can improve the NOx conversion efficiency. While for V‐SCR, the HNCO hydrolysis reaction can become the rate‐limiting step (especially after aging), abundant urea at low temperatures impairs NOx reduction.
Status and Perspectives of Biomass Use for Industrial Process Heat for Industrialized Countries
Authors: Lenz Volker , Szarka Nora , Jordan Matthias , Thrän Daniela
Published: May 2020

Full reduction of greenhouse gas emissions involves transforming the industrial process heat supply. The status and future perspectives of biomass for industrial heat mainly based on the German example are reviewed, and a more differentiated consideration by a newly introduced method is attempted. The article focuses on temperature levels above 200 °C combined with an individual examination of most energy‐consuming industrial subsectors according to the feasibility of biomass utilization. Numerous studies conclude that biomass use will shift substantially from residential to industrial heat. Results indicate that biomass could play a bigger role especially for cement and clinker production, but they indicate also a significant need for further research and development to take final conclusions.
pH Tuning of Water‐Soluble Arylazopyrazole Photoswitches
Authors: Ludwanowski Simon , Ari Meral , Parison Karsten , Kalthoum Somar , Straub Paula , Pompe Nils , Weber Stefan , Walter Michael , Walther Andreas
Published: May 2020

Arylazopyrazoles are an emerging class of photoswitches with redshifted switching wavelength, high photostationary states, long thermal half‐lives and facile synthetic access. Understanding pathways for a simple modulation of the thermal half‐lives, while keeping other parameters of interest constant, is an important aspect for out‐of‐equilibrium systems design and applications. Here, it is demonstrated that the thermal half‐life of a water‐soluble PEG‐tethered arylazo‐bis(o‐methylated)pyrazole (AAP) can be tuned by more than five orders of magnitude using simple pH adjustment, which is beyond the tunability of azobenzenes. The mechanism of thermal relaxation is investigated by thorough spectroscopic analyses and density functional theory (DFT) calculations. Finally, the concepts of a tunable half‐life are transferred from the molecular scale to the material scale. Based on the photochromic characteristics of E‐ and Z‐AAP, transient information storage is showcased in form of light‐written patterns inside films cast from different pH, which in turn leads to different times of storage. With respect to prospective precisely tunable materials and time‐programmed out‐of‐equilibrium systems, an externally tunable half‐life is likely advantageous over changing the entire system by the replacement of the photoswitch.
Evaluation of Pd→B Interactions in Diphosphinoborane Complexes and Impact on Inner‐Sphere Reductive Elimination
Authors: Ritter Florian , John Lukas , Schindler Tobias , Schroers Julian P. , Teeuwen Simon , Tauchert Michael E.
Published: May 2020

The dative Pd→B interaction in a series of RDPBR’ Pd0 and PdII complexes (RDPBR’=(o‐PR2C6H4)2BR’, diphosphinoborane) was analyzed using XRD, 11B NMR spectroscopy and NBO/NLMO calculations. The borane acceptor discriminates between the oxidation state PdII and Pd0, stabilizing the latter. Reaction of lithium amides with [(RDPBR’)PdII(4‐NO2C6H4)I] chemoselectively yields the C−N coupling product. DFT modelling indicates no significant impact of PdII→B coordination on the inner‐sphere reductive elimination rate.
Thermo‐Sensitive Dual‐Functional Nanospheres with Enhanced Lubrication and Drug Delivery for the Treatment of Osteoarthritis
Authors: Zhang Kuan , Yang Jielai , Sun Yulong , He Mingrui , Liang Jing , Luo Jing , Cui Wenguo , Deng Lianfu , Xu Xiangyang , Wang Bo , Zhang Hongyu
Published: May 2020

Osteoarthritis is a typical degenerative joint disease related to a lubrication deficiency of articular cartilage, which is characterized by increased friction at the joint surface and severe inflammation of the joint capsule. Consequently, therapies combining lubrication restoration and drug intervention are regarded as a promising strategy for the treatment of osteoarthritis. In the present study, thermo‐sensitive dual‐functional nanospheres, poly[N‐isopropylacrylamide‐2‐methacryloyloxyethyl phosphorylcholine] (PNIPAM‐PMPC), are developed through emulsion polymerization. The PNIPAM‐PMPC nanospheres could enhance lubrication based on the hydration lubrication mechanism by forming a tenacious hydration layer surrounding the zwitterionic headgroups, and achieve local drug delivery by encapsulating the anti‐inflammatory drug diclofenac sodium. The lubrication and drug release tests showed improved lubrication and thermo‐sensitive drug release of the nanospheres. The in vitro test using cytokines‐treated chondrocytes indicated that the PNIPAM‐PMPC nanospheres were biocompatible and upregulated anabolic genes and simultaneously downregulated catabolic genes of the articular cartilage. In summary, the developed PNIPAM‐PMPC nanospheres, with the property of enhanced lubrication and local drug delivery, can be an effective nanomedicine for the treatment of osteoarthritis.
Exploring the Limits of π‐Acid Catalysis Using Strongly Electrophilic Main Group Metal Complexes: The Case of Zinc and Aluminium
Authors: Tian Jiaxin , Chen Yan , Vayer Marie , Djurovic Alexandre , Guillot Régis , Guermazi Refka , Dagorne Samuel , Bour Christophe , Gandon Vincent
Published: May 2020

The catalytic activity of cationic NHC‐ZnII and NHC‐AlIII (NHC=N‐heterocyclic carbene) complexes in reactions that require the electrophilic activation of soft C−C π bonds has been studied. The former proved able to act as a soft π‐Lewis acid in a variety of transformations. The benefit of the bulky IPr NHC ligand was demonstrated by comparison with simple ZnX2 salts. The tested NHC‐AlIII catalyst is not able to activate C−C π bonds but simple AlX2+ ions were found potent in some cases.
Oxidation of cis‐Diamminediacetato PtII with Hydrogen Peroxide Can Give Rise to Two Isomeric PtIV Products
Authors: Khattib D. , Ishan M. , Karmakar S. , Kostrhunova H. , Brabec V. , Gibson D.
Published: May 2020

The oxidation of cis‐[Pt(NH3)2(OAc)2] with H2O2 yields a mixture of two isomers: ctc‐[Pt(NH3)2(OH)2(OAc)2] and ctc‐[Pt(NH3)2(OH)(OAc)(OH)(OAc)]. Following modification with 4‐phenylbutyric (PhB) anhydride, two isomers were separated and characterized; the symmetric ctc‐[Pt(NH3)2(PhB)2(OAc)2] (1) and the nonsymmetric ctc‐[Pt(NH3)2(PhB)(OAc)(PhB)(OAc)] (2). They differ in their log P values and despite having similar cellular uptake and similar DNA platination levels, the symmetric ctc‐[Pt(NH3)2(OH)2(OAc)2] is more than 4‐fold more potent than the nonsymmetric isomer in a panel of 4 cancer cell lines.
Prebiotic Nucleoside Synthesis: The Selectivity of Simplicity
Authors: Kruse Florian M. , Teichert Jennifer S. , Trapp Oliver
Published: May 2020

Ever since the discovery of nucleic acids 150 years ago,[1] major achievements have been made in understanding and decrypting the fascinating scientific questions of the genetic code.[2] However, the most fundamental question about the origin and the evolution of the genetic code remains a mystery. How did nature manage to build up such intriguingly complex molecules able to encode structure and function from simple building blocks? What conditions were required? How could the precursors survive the unhostile environment of early Earth? Over the past decades, promising synthetic concepts were proposed providing clarity in the field of prebiotic nucleic acid research. In this Minireview, we show the current status and various approaches to answer these fascinating questions.
Transition‐Metal‐Free Coupling of 1,3‐Dipoles and Boronic Acids as a Sustainable Approach to C−C Bond Formation
Authors: Livingstone Keith , Bertrand Sophie , Kennedy Alan R. , Jamieson Craig
Published: May 2020

The need for alternative, complementary approaches to enable C−C bond formation within organic chemistry is an on‐going challenge in the area. Of particular relevance are transformations that proceed in the absence of transition‐metal reagents. In the current study, we report a comprehensive investigation of the coupling of nitrile imines and aryl boronic acids as an approach towards sustainable C−C bond formation. In situ generation of the highly reactive 1,3‐dipole facilitates a Petasis–Mannich‐type coupling via a nucleophilic boronate complex. The introduction of hydrazonyl chlorides as a complementary nitrile imine source to the 2,5‐tetrazoles previously reported by our laboratory further broadens the scope of the approach. Additionally, we exemplify for the first time the extension of this protocol into another 1,3‐dipole, through the synthesis of aryl ketone oximes from aryl boronic acids and nitrile N‐oxides.
Chiral Versus Non‐Chiral [MnIII6MnIINaI], [MnIII6MnII2NaI2] and [MnIII3MnIINaI] Clusters Derived from Schiff Bases or the Fight for Symmetry
Authors: Pilichos Evangelos , Escuer Albert , Font‐Bardia Mercé , Mayans Júlia
Published: May 2020

The reaction in basic media of manganese chloride with Schiff bases derived from the condensation of o‐vanillin with different chiral/racemic aminoalcohols yielded in a family of complexes in which the nuclearity, symmetry and magnetic behavior is controlled by changing the position of the chiral carbon. Chiral and racemic clusters with [MnIII6MnIINaI], [MnIII6MnII2NaI2] and [MnIII3MnIINaI] metallic core have been structurally and magnetically characterized. The racemic clusters with an odd number of chiral ligands exhibit the anomalous mixing of ligands with different conformation. Related racemic compounds have been reviewed.
Programming DNA‐Based Systems through Effective Molarity Enforced by Biomolecular Confinement
Authors: Rossetti Marianna , Bertucci Alessandro , Patiño Tania , Baranda Lorena , Porchetta Alessandro
Published: May 2020

The fundamental concept of effective molarity is observed in a variety of biological processes, such as protein compartmentalization within organelles, membrane localization and signaling paths. To control molecular encountering and promote effective interactions, nature places biomolecules in specific sites inside the cell in order to generate a high, localized concentration different from the bulk concentration. Inspired by this mechanism, scientists have artificially recreated in the lab the same strategy to actuate and control artificial DNA‐based functional systems. Here, it is discussed how harnessing effective molarity has led to the development of a number of proximity‐induced strategies, with applications ranging from DNA‐templated organic chemistry and catalysis, to biosensing and protein‐supported DNA assembly.
Halogen‐Bonded Assemblies of Arylene Imides and Diimides: Insight from Electronic, Structural, and Computational Studies
Authors: Mandal Kalyanashis , Bansal Deepak , Kumar Yogendra , Rustam  , Shukla Jyoti , Mukhopadhyay Pritam
Published: May 2020

Halogen‐bonding interactions in electron‐deficient π scaffolds have largely been underexplored. Herein, the halogen‐bonding properties of arylene imide/diimide‐based electron‐deficient scaffolds were studied. The influence of scaffold size, from small (phthalimide) to moderately sized (pyromellitic diimide or naphthalenediimides) to large (perylenediimide), axial‐group modification, and number of halo substituents on the halogen bonding and its self‐assembly was probed in a set of nine compounds. The structural modification leads to tunable optical and redox properties. The first reduction potentialranges between −1.09 and −0.17 V (vs. SCE). Two of the compounds, that is,6and9, have deep‐lying LUMOs with values reaching −4.2 eV. Single crystals of all nine systems were obtained, which showed Br⋅⋅⋅O, Br⋅⋅⋅Br, or Br⋅⋅⋅π halogen‐bonding interactions, and a few systems are capable of forming all three types. These interactions lead to halogen‐bonded rings (up to 12‐membered), which propagate to form stacked 1D, 2D, or corrugated sheets. A few outliers were also identified, for example, molecules that prefer C−H⋅⋅⋅O hydrogen bonding over halogen bonding, or noncentrosymmetric rather than centrosymmetric organization. Computational studies based on Atoms in Molecules and Natural Bond Orbital analysis provided further insight into the halogen‐bonding interactions. This study can lead to a predictive design tool‐box to further explore related systems on surfaces reinforced by these weak directional forces.
Switching the Switch: Ligand Induced Disulfide Formation in HDAC8
Authors: Jänsch Niklas , Sugiarto Wisely Oki , Muth Marius , Kopranovic Aleksandra , Desczyk Charlotte , Ballweg Matthias , Kirschhöfer Frank , Brenner‐Weiss Gerald , Meyer‐Almes Franz‐Josef
Published: May 2020

Human histone deacetylase 8 is a well‐recognized target for T‐cell lymphoma and particularly childhood neuroblastoma. PD‐404,182 was shown to be a selective covalent inhibitor of HDAC8 that forms mixed disulfides with several cysteine residues and is also able to transform thiol groups to thiocyanates. Moreover, HDAC8 was shown to be regulated by a redox switch based on the reversible formation of a disulfide bond between cysteines Cys102 and Cys153. This study on the distinct effects of PD‐404,182 on HDAC8 reveals that this compound induces the dose‐dependent formation of intramolecular disulfide bridges. Therefore, the inhibition mechanism of HDAC8 by PD‐404,182 involves both, covalent modification of thiols as well as ligand mediated disulfide formation. Moreover, this study provides a deep molecular insight into the regulation mechanism of HDAC8 involving several cysteines with graduated capability to form reversible disulfide bridges.
Amphiphilic Polymeric Nanoparticles for Photoredox Catalysis in Water
Authors: Eisenreich Fabian , Meijer E. W. , Palmans Anja R. A.
Published: May 2020

Photoredox catalysis has recently emerged as a powerful synthesis tool in organic and polymer chemistry. In contrast to the great achievements realized in organic solvents, performing photocatalytic processes efficiently in aqueous media encounters several challenges. Here, it is presented how amphiphilic single‐chain polymeric nanoparticles (SCPNs) can be utilized as small reactors to conduct light‐driven chemical reactions in water. By incorporating a phenothiazine (PTH) catalyst into the polymeric scaffold, metal‐free reduction and C−C cross‐coupling reactions can be carried out upon exposure to UV light under ambient conditions. The versatility of this approach is underlined by a large substrate scope, tolerance towards oxygen, and excellent recyclability. This approach thereby contributes to a sustainable and green way of implementing photoredox catalysis.
Catalytic Asymmetric Total Synthesis of Exiguolide
Authors: Oka Kengo , Fuchi Shunsuke , Komine Keita , Fukuda Hayato , Hatakeyama Susumi , Ishihara Jun
Published: May 2020

The catalytic asymmetric total synthesis of (−)‐exiguolide, a complex 20‐membered macrolide embedded with a bis(tetrahydropyran) motif, is reported. The convergent synthesis involves the construction of the C1–C11 tetrahydropyran segment via catalytic asymmetric allylation and Prins cyclization, and the formation of the C12–C21 phosphonate segment via catalytic asymmetric cyclocondensation reaction and Johnson–Claisen rearrangement. The synthesis of 15‐epi‐exiguolide is also described.
Unprecedented Reverse Volume Expansion in Spin‐Transition Crystals
Authors: Guo Wenbin , Daro Nathalie , Pillet Sébastien , Marchivie Mathieu , Bendeif El‐Eulmi , Tailleur Elodie , Chainok Kittipong , Denux Dominique , Chastanet Guillaume , Guionneau Philippe
Published: May 2020

The current craze for research around the spin crossover phenomenon can be justified to some extent by the mechanical properties due to the decrease of volume associated with the transition of the metal ion from the HS state to the LS state. As demonstrated here, the molecular complex [Fe(PM‐pBrA)2(NCS)2] exhibits, on the contrary, an increase of the unit‐cell volume from HS to LS. This counter‐intuitive and unprecedented behavior that concerns both the thermal and the photoexcited spin conversions is revealed by a combination of single‐crystal and powder X‐ray diffraction complemented by magnetic measurements. Interestingly, this abnormal volume change appears concomitant with the wide rotation of a phenyl ring which induces a drastic modification, though reversible, of the structural packing within the crystal. In addition, the light‐induced HS state obtained through the Light‐Induced Excited Spin‐State Trapping shows a remarkably high relaxation temperature, namely T(LIESST), of 109 K, one of the highest so far reported. The above set of quite unusual characteristics opens up new fields of possibilities within the development of spin crossover materials.
From Bowls to Capsules: Assembly of Hexanuclear NiII Rings Tailored by Alkali Cations
Authors: Mayans Júlia , Stoumpos Constantinos C. , Font‐Bardia Mercé , Escuer Albert
Published: May 2020

An anionic hexanuclear NiII metallamacrocycle with endo and exo linking sites has been employed as a building block to generate a series of capsules and bowls of nanometric size. The supramolecular arrangement of the {Ni6} rings was tailored by the size of the alkali cations, showing the transition from {Ni6‐M2‐Ni6} capsules (M=LiI and NaI) to {Ni6‐M} bowls (M=KI and CsI). The alkyl co‐cations are determinant to stabilize the assemblies by means of CH⋅⋅⋅π interactions on the exo side of the metallamacrocycles. The effect on the topology of the supramolecular assemblies of the cation size, cation charge, Et3NH+ or Me4N+ counter cations has been analyzed. Magnetic measurements reveal the presence of ferromagnetic and antiferromagnetic interactions inside the rings that allow a S=0 ground state.
Synthesis of Highly Enantioenriched Sulfonimidoyl Fluorides and Sulfonimidamides by Stereospecific Sulfur–Fluorine Exchange (SuFEx) Reaction
Authors: Greed Stephanie , Briggs Edward L. , Idiris Fahima I. M. , White Andrew J. P. , Lücking Ulrich , Bull James A.
Published: May 2020

Sulfonimidamides present exciting opportunities as chiral isosteres of sulfonamides, with potential for additional directional interactions. Here, we present the first modular enantioselective synthesis of sulfonimidamides, including the first stereoselective synthesis of enantioenriched sulfonimidoyl fluorides, and studies on their reactivity. A new route to sulfonimidoyl fluorides is presented from solid bench‐stable, N‐Boc‐sulfinamide (Boc=tert‐butyloxycarbonyl) salt building blocks. Enantioenriched arylsulfonimidoyl fluorides are shown to be readily racemised by fluoride ions. Conditions are developed, which trap fluoride and enable the stereospecific reaction of sulfonimidoyl fluorides with primary and secondary amines (100 % es, es=enantiospecificity) generating sulfonimidamides with up to 99 % ee. Aryl and alkyl sulfonimidoyl fluoride reagents are suitable for mild late stage functionalisation reactions, exemplified by coupling with a selection of complex amines in marketed drugs.
An Ultra‐Microporous Metal–Organic Framework with Exceptional Xe Capacity
Authors: Chakraborty Debanjan , Nandi Shyamapada , Maity Rahul , Motkuri Radha Kishan , Han Kee Sung , Collins Sean , Humble Paul , Hayes James C. , Woo Tom K. , Vaidhyanathan Ramanathan , Thallapally Praveen K.
Published: May 2020

Molecular confinement plays a significant effect on trapped gas and solvent molecules. A fundamental understanding of gas adsorption within the porous confinement provides information necessary to design a material with improved selectivity. In this regard, metal–organic framework (MOF) adsorbents are ideal candidate materials to study confinement effects for weakly interacting gas molecules, such as noble gases. Among the noble gases, xenon (Xe) has practical applications in the medical, automotive and aerospace industries. In this Communication, we report an ultra‐microporous nickel‐isonicotinate MOF with exceptional Xe uptake and selectivity compared to all benchmark MOF and porous organic cage materials. The selectivity arises because of the near perfect fit of the atomic Xe inside the porous confinement. Notably, at low partial pressure, the Ni–MOF interacts very strongly with Xe compared to the closely related Krypton gas (Kr) and more polarizable CO2. Further 129Xe NMR suggests a broad isotropic chemical shift due to the reduced motion as a result of confinement.
Interplay Between Planar and Spherical Aromaticity: Shielding Cone Behavior in Dual Planar‐Planar, Planar‐Spherical and Spherical‐Spherical Aromatics
Authors: Muñoz‐Castro Alvaro
Published: May 2020

The shielding cone concept is one of the most characteristic aspects of planar aromatic species. Herein, we explored how two neighbor aromatic moieties behave as dual planar‐planar, planar‐spherical, and spherical‐spherical species given by biphenyl, [PhCB11H11]−, and [CB11H11]22−, respectively. Our results show two separate aromatic regimes given by Clar's sextet and spherical aromatic states, with independent shielding cones sharing shielding regions of moderate strength, which can be extended for networks involving multiple independent aromatic states.
Flow Cytometry Assessment of Microalgae Physiological Alterations under CO2 Injection
Authors: Galotti Andréa , Jiménez‐Gómez Francisco , Parra Gema
Published: May 2020

Growth rate (GR), esterase activity (EA), membrane potential (MP), and DNA content were measured by flow cytometry to test if this powerful tool could be included in risk assessment and monitoring programs. This study tests a battery of endpoints that were measured on Scenedesmus (Acutodesmus) obliquus as model species, under high levels of injected CO2 to be proposed as biomarkers of effect. New technologies such as carbon capture and storage (CCS) bring positive consequences on CO2 mitigation strategies but also could have negative consequences if a CO2 leakage occurs during injection. Under this scenario, pH might drop down to 4 pH units around the pipe where the leakage happens. The study focus on to ascertain if the endpoints fulfill the requirements such as sensitiveness, be timely and cost‐effective, be easy to measure and interpret, and be nondestructive, valuable attributes in effective biomarkers. CO2 injected at high levels significantly affects the EA, the membrane polarization, as well as GRs. However the DNA content did not shown a clear response under this condition. In conclusion, the GR, the EA, and the MP analyzed by flow cytometry fulfilled the attributes mentioned above and are proposed as biomarkers of effect in CCS monitoring programs. © 2020 International Society for Advancement of Cytometry
Plasma levels of one‐carbon metabolism nutrients in women with anorexia nervosa
Authors: Burdo Jessica , Booij Linda , Kahan Esther , Thaler Lea , Israël Mimi , Agellon Luis B. , Nitschmann Evan , Wykes Linda , Steiger Howard
Published: May 2020

Objective

People who are ill with anorexia nervosa (AN) show altered availability of key plasma nutrients. However, little is known about the patterning of alterations that occurs across diverse nutrients during active phases of illness or about the persistence of any such alterations following remission of illness.

Method

We compared plasma levels of one‐carbon metabolism nutrients across women with active AN (AN‐Active: n = 53), in remission from AN (AN‐Remitted: n = 40), or who had no eating‐disorder history (NED: n = 36). We also tested associations between body mass index (BMI) changes and changes in pre‐ to posttreatment nutrient levels, and explored the association between nutrient levels, on the one hand, and BMI and eating symptoms, on the other. Choline, betaine, and methionine were analyzed using mass spectrometry. Folate and B12 were analyzed using the AccuBind® ELISA kit. Eating‐disorder symptoms were assessed by interview and self‐report.

Results

Compared to NED individuals, AN‐Active individuals exhibited significantly elevated B12 and (less‐reliably) betaine. In AN‐Active individuals, lower BMI was associated with higher B12.

Discussion

The observed alterations run contrary to the intuition that plasma nutrient levels should be directly responsive to nutritional status and suggest, instead, the existence of compensatory adaptations to malnutrition in individuals with active AN. Further study is required to clarify mechanisms that underlie such effects.
Genetic structure among morphotypes of the endangered Brazilian palm Euterpe edulis Mart (Arecaceae)
Authors: Coelho Gislaine Mendes , Santos Alesandro Souza , de Menezes Ivandilson Pessoa Pinto , Tarazi Roberto , Souza Fernanda Maria Oliveira , Silva Maria das Graças Conceição Parada Costa , Gaiotto Fernanda Amato
Published: May 2020

Euterpe edulis (Arecaceae) Mart has high ecological and economic importance providing food resources for more than 58 species of birds and 20 species of mammals, including humans. E. edulis is the second most exploited nontimber product from Brazilian Atlantic Forest. Due to overexploitation and destruction of habitats, E. edulis is threatened by extinction. Euterpe edulis populations have large morphological variations, with individuals having green, red, or yellow leaf sheath. However, no study has related phenotypic distinctions between populations and their levels of genetic structure. Thus, this study aimed to evaluate the diversity and genetic structure of different E. edulis morphotypes. We sampled 250 adult individuals in eight populations with the different morphotypes. Using 14 microsatellite markers, we access genetic diversity through population genetic parameters calculated in the GenAlex program and the diveRsity package in R. We used the Wilcoxon test to verify population bottlenecks and the genetic distance of Nei and Bayesian analysis for genetic clusters. The eight populations showed low allele richness, low observed heterozygosity, and high inbreeding values (f). In addition, six of the eight populations experienced genetic bottlenecks, which would partly explain the low genetic diversity in populations. Cluster analysis identified two clusters (K = 2), with green morphotype genetically distinguishing from yellow and red morphotypes. Thus, we show, for the first time, a strong genetic structure among E. edulis morphotypes even for geographically close populations.
The relative performance of sampling methods for native bees: an empirical test and review of the literature
Authors: Prendergast Kit S. , Menz Myles H. M. , Dixon Kingsley W. , Bateman Philip W.
Published: May 2020

Many bee species are declining globally, but to detect trends and monitor bee assemblages, robust sampling methods are required. Numerous sampling methods are used, but a critical review of their relative effectiveness is lacking. Moreover, evidence suggests the relative effectiveness of sampling methods depends on habitat, yet efficacy in urban areas has yet to be evaluated. This study compared the bee community documented using observational records, targeted netting, mobile gardens, pan traps (blue and yellow), vane traps (blue and yellow), and trap‐nests. The comparative surveys of native bees and honeybees were undertaken in an urbanized region of the southwest Australian biodiversity hot spot. The outcomes of the study were then compared to a synthesis based on a comprehensive literature review of studies where two or more bee sampling methods were conducted. Observational records far exceeded all other methods in terms of abundance of bees recorded, but were unable to distinguish finer taxonomic levels. Of methods that captured individuals, thereby permitting taxonomic identification, targeted sweep netting vastly outperformed the passive sampling methods, yielding a total of 1324 individuals, representing 131 taxonomic units—even when deployed over a shorter duration. The relative effectiveness of each method differed according to taxon. From the analysis of the literature, there was high variability in relative effectiveness of methods, but targeted sweep netting and blue vane traps tended to be most effective, in accordance with results from this study. However, results from the present study differed from most previous studies in the extremely low catch rates in pan traps. Species using trap‐nests represented only a subset of all potential cavity‐nesters, and their relative abundances in the trap‐nests differed from those in the field. Mobile gardens were relatively ineffective at attracting bees. For urbanized habitat within this biodiversity hot spot, targeted sweep netting is indispensable for obtaining a comprehensive indication of native bee assemblages; passive sampling methods alone recorded only a small fraction of the native bee community. Overall, a combination of methods should be used for sampling bee communities, as each has their own biases, and certain taxa were well represented in some methods, but poorly represented in others.
A hierarchical framework for estimating abundance and population growth from imperfectly observed removals
Authors: Stevens Bryan S. , Bence James R. , Luukkonen David R. , Porter William F.
Published: May 2020

Estimating abundance and growth of animal populations are central tasks in ecology and natural resource management. Removal models for estimating abundance have a long history in applied ecology, and recent developments provided hierarchical extensions that account for spatially replicated sampling and heterogeneous capture probabilities. Measurement error is common to removal data collected from many broad‐scale monitoring programs, however, and a general framework for population assessment using removal data in the presence of measurement error is lacking. We developed a hierarchical framework for estimating abundance and population trends from removal experiments that are replicated in space and time that accommodates measurement error, as well as heterogeneity in capture probability and animal density. We describe the model for variable‐effort removal sampling and use it to estimate region‐specific abundance and population trends for wild turkeys (Meleagris gallopavo) in Michigan, USA. We used a Bayesian approach for estimation and inference and fit models using daily hunter harvest and effort estimates collected over 5 management regions for 14 annual hunting seasons. Our analyses provide evidence for spatially heterogeneous capture probabilities among regions and turkey densities that were heterogeneous in both space and time, and show that populations increased slightly over the study. Our framework provides a general approach for population assessment using removal data that are collected over broad scales in resource management contexts (e.g., animal harvesting), facilitating formal abundance estimation instead of reliance on unverified indices for tracking populations of managed species. Thus, we provide a useful tool for monitoring programs to assess populations over broad scales, and therefore inform decision makers about population status at spatial scales similar to those for which regulatory decisions are made.
Seasonal and interannual variations in functional traits of sown and spontaneous species in vineyard inter‐rows
Authors: Garcia Léo , Damour Gaëlle , Kazakou Elena , Fried Guillaume , Bopp Marie‐Charlotte , Metay Aurélie
Published: May 2020

The trait‐based approach can address questions in order to understand how the functioning of organisms scales up to that of ecosystems and controls some of the services they deliver to humans, including in agriculture. However, the importance of interspecific vs the intraspecific trait variability (ITV) for classifying species according to their traits in agrosystems on a large diversity of pedoclimatic situations and cropping systems remains still open. Here, we addressed three questions: How do measured traits vary across years and seasons? Are species rankings conserved across years and season? And which traits and species are the more stable and repeatable for sown and spontaneous species? We conducted a two‐year experiment in a vineyard, and we measured four leaf and plant functional traits of 14 sown species and 43 spontaneous species that grew among sown species. Traits were measured at two key phenological stages for grapevine: budburst and flowering during two successive years with contrasted rainfall (2017 and 2018). We studied seasonal and interannual trait variations, rankings between species, and variance partitioning. The species factor explained the greatest part of trait variations across years and seasons. Sown and spontaneous species traits varied in the same way, and traits related to plant dry matter contents were the more stable across periods. Moreover, species rankings were conserved across years and seasons for all traits except plant height. Sown species showed better ranking conservation than spontaneous species overall. The trait‐based approach seems promising for the comparison of various cropping systems involving sown and spontaneous species, and may help identifying service crop species related to specific agroecosystem services. Further research is needed to bring more knowledge on trait variations under a diversity of agrosystems, and to improve theoretical frameworks that would help the design of sustainable agrosystems that provide multiple ecosystem services.
On the mechanistic understanding of predator feeding behavior using the functional response concept
Authors: Papanikolaou Nikos E. , Broufas George D. , Papachristos Dimitrios P. , Pappas Maria L. , Kyriakaki Chara , Samaras Konstantinos , Kypraios Theodore
Published: May 2020

Functional response models describe the relationship between prey density and per capita prey consumption rate by a predator. Type II functional responses, in which density‐dependent predation occurs via a decelerating feeding rate, seem to prevail in nature and are commonly described by Holling’s disk equation. In the derivation of the disk equation, Holling did not include digestion time. Although some authors have later extended the interpretation of handling time by also including digestion time, this violates the key assumption of the disk equation that the processes of searching for and handling prey are mutually exclusive. The steady‐state satiation (SSS) equation is a functional response model that discriminates between handling and digestion time. The application of the SSS equation is underutilized so far in the ecological literature, probably due to its complexity. In this study, we first tested the viability of the SSS equation. Second, we investigated the mechanistic basis of the SSS equation, comparing the model’s predictions with directly observed data. For this purpose, we used predator–prey systems of different taxa, that is, the ladybird beetle Hippodamia variegata preying on the aphid Aphis fabae, the lacewing Chrysoperla agilis preying on the aphid Myzus persicae, and the predatory mite Iphiseius degenerans preying on the thrips Frankliniella occidentalis. Our results show that the SSS equation is viable and can realistically describe type II functional response. In all predator–prey systems we tested, the model fitted the data reasonably well and provided realistic estimation of its parameters.