bluuebunny/crossref_metadata_2025 huggingface dataset:
Le dedans et le dehors : une exploration de la dynamique pré-réfléchie de l’expérience corporelle
Authors: Petitmengin Claire
Published: March 2021

Cet article explore une dimension profondément pré-réfléchie de notre expérience corporelle, qui semble jouer un rôle essentiel dans la genèse d’une perception, d’une compréhension, comme dans nos relations interpersonnelles. A partir de plusieurs exemples, j’examinerai les caractéristiques structurelles de cette dimension, qui semblent très différentes de celles de notre expérience ordinaire. Notamment, la distinction entre un espace “intérieur” et un espace “extérieur”, entre un sujet percevant et un objet perçu, et entre les différentes modalités sensorielles, y est beaucoup plus perméable que dans l’expérience dont nous sommes habituellement conscients. Cette exploration me conduira à faire l’hypothèse que la séparation entre intérieur et extérieur, loin d’être donnée, est le résultat d’une activité pré-réfléchie destinée à construire et à maintenir cette fracture.
Enjeux de la collaboration entre chercheur et formateur dans la conception de la formation des sages-femmes : une étude de cas dans une consultation au 8 ème mois de la grossesse
Authors: Vinatier Isabelle , Le Guillanton Nathalie
Published: March 2021

Exerçant une profession médicale, les sages-femmes doivent assurer, en toute autonomie, le diagnostic et la surveillance pré, péri et postnatale. Le raisonnement clinique, essentiel dans leur formation, est un processus de pensée reconnu comme difficile à construire, aussi bien pour les étudiants que pour les formateurs. Lors d’une consultation «formative », une analyse clinique de l’interaction entre une étudiante (accompagnée par une formatrice) et la patiente, montre les obstacles et les aléas auxquels se confrontent la formatrice et l’étudiante. Dans le cadre théorique de la didactique professionnelle, la recherche collaborative, initiée par les deux auteurs, permet d’articuler de manière heuristique savoirs professionnels et savoirs de la recherche et de comprendre ainsi en quoi et comment le raisonnement clinique est soumis au fonctionnement de l’interaction dans le contexte d’exercice des soignantes (à la fois institutionnel et juridique), à des enjeux identitaires (formatrice et étudiante face à une patiente) et à la relation développée avec la patiente. La collaboration développée dans le cadre de cette recherche, entre chercheur et professionnelle de la formation, ouvre une nouvelle perspective de formation au raisonnement clinique, autour d’études de cas d’interactions problématiques qui font événement pour les étudiants mais également pour les sages-femmes formatrices .
Le développement des compétences professionnelles en formation des maîtres : étude comparative et longitudinale de deux maîtres stagiaires
Authors: Baconnet Sophie
Published: March 2021

L’objet d’étude de cet article est ergo-didactique. Il vise à mieux éclairer la problématique du développement professionnel des enseignants en formation. Il s’agit de comparer deux trajectoires professionnelles singulières à l’œuvre dans deux contextes différents. Dans cette étude, nous postulons que le développement professionnel peut s’accélérer sous certaines conditions. L’étude s’appuie notamment sur le cadre conceptuel du multi-agenda de l’enseignant selon kucheton (2003). Elle s’intéresse aux modalités langagières convoquées par deux enseignants stagiaires dans le cadre de leur stage, impliqués dans un dispositif de formation innovant, l’atelier dirigé d’écriture. La méthode privilégie des données objectives (séances de classe filmées retranscrites dans des verbatim) suivies d’entretiens d’auto-confrontation de l’enseignant face à son activité de classe selon Clot (1999). Les entretiens sont analysés de manière longitudinale dans le temps, de façon à dévoiler les logiques propres aux acteurs. Deux logiques de développement sont rendues manifestes, aboutie dans un cas, inachevée dans l’autre .
Se professionnaliser dans une logique de compétences : le cas des étudiants infirmiers
Authors: Do Marine
Published: March 2021

Ce travail porte sur le changement opéré en formation professionnelle infirmière, suite à la réforme de 2009. Il se propose de rendre compte des pratiques de professionnalisation émergentes et de la manière dont les tuteurs-infirmiers ont su se saisir des nouvelles logiques de formation pour accompagner les étudiants dans leur parcours de professionnalisation. La réflexion théorique proposée permet d’éclairer les nouveaux rapports aux savoirs dans la logique de construction de compétences. Les résultats s’appuient sur des observations participantes, trente-cinq entretiens semi-directifs collectifs et individuels, réalisés auprès de différents acteurs concernés par la professionnalisation des novices, dans deux structures hospitalières, à des temps distincts. L’analyse a permis d’identifier des logiques différentes de changement et l’intérêt d’un accompagnement des acteurs de terrain, pour une transformation durable de leurs pratiques.
COVID-19 in US Youth Soccer Athletes During Summer 2020
Authors: Watson Andrew M. , Haraldsdottir Kristin , Biese Kevin M. , Goodavish Leslie , Stevens Bethany , McGuine Timothy A.
Published: March 2021

Context

As sports are reinitiated around the United States, the incidence of COVID-19 among youth soccer athletes remains unknown.

Objective

To determine the incidence of COVID-19 among youth soccer athletes and the risk-mitigation practices used by youth soccer organizations.

Design

Cohort study.

Setting

Survey distributed to Elite Clubs National League member clubs.

Patients or Other Participants

Youth soccer club directors throughout the United States.

Main Outcome Measure(s)

Surveys were completed in late August 2020 regarding the club's current phase of return to soccer (individual only, group noncontact, group contact), date of reinitiation, number of players, cases of COVID-19, and risk-reduction procedures being implemented. Case and incidence rates were compared with national pediatric data and county data from the prior 10 weeks. A negative binomial regression model was developed to predict club COVID-19 cases using the local incidence rate and phase of return as covariates and the log of club player-days as an offset.

Results

A total of 124 respondents had reinitiated soccer, representing 91 007 players with a median duration of 73 days (interquartile range = 53–83 days) since restarting. Of the 119 clubs that had progressed to group activities, 218 cases of COVID-19 were reported among 85 861 players. Youth soccer players had a lower case rate and incidence rate than children in the United States (254 versus 477 cases per 100 000; incidence rate ratio = 0.511, 95% CI = 0.40, 0.57; P < .001) and the general population in the counties where data were available (268 versus 864 cases per 100 000; incidence rate ratio = 0.202, 95% CI = 0.19, 0.21; P < .001). After adjusting for the local COVID-19 incidence, we found no relationship between the club COVID-19 incidence and the phase of return (noncontact: b = 0.35 ± 0.67, P = .61; contact: b = 0.18 ± 0.67, P = .79). Soccer clubs reported using a median of 8 (interquartile range = 6–10) risk-reduction procedures.

Conclusions

The incidence of COVID-19 among youth soccer athletes was relatively low when compared with the background incidence among children in the United States during the summer of 2020. No relationship was identified between the club COVID-19 incidence and the phase of return to soccer.
The mouse double minute 2 309T>G polymorphism and retinoblastoma risk
Authors: Sooraj K. , Kumar Sunil , Kumar Amit , Bajaj Mandeep S. , Kaur Jasbir
Published: March 2021

PURPOSE:

Mouse double minute 2 (MDM2) homolog is a protein that in humans is encoded by the MDM2 gene. It is expressed in retinoblastoma (Rb) cells and acts as a key negative regulator of the p53 tumor suppressor gene. Several studies have investigated the association of Rb with MDM2 309T>G polymorphism, but the results were conflicting. To derive a more precise estimation of the association, we performed a meta-analysis of the relationship between MDM2 309T>G polymorphism with Rb in all published studies.

METHODS:

Published literature from PubMed and other databases were retrieved. All the reported studies evaluating the association between MDM2 309T>G polymorphism and Rb risk were included. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using the fixed-effect model. A total of four case–control studies, including 520 cases and 745 controls were included.

RESULTS:

This meta-analysis found that MDM2 309T>G polymorphism was significantly associated with Rb risk in the dominant model, TG+GG versus TT (OR = 1.43, 95% CI = 1.11–1.84, P = 0.006).

CONCLUSION:

The present meta-analysis suggested that MDM2 309T>G polymorphism has a significant association with increased Rb risk.
Ocularists the less known mid eye care professionals and their contribution in eye health care
Authors: Changal Nusrat , AlRasheed Waleed , Khandekar Rajiv
Published: March 2021

Ocularists are ophthalmic technicians usually working at oculoplastics departments in tertiary eye hospitals. They prepare, provide, fit and maintain ocular or orbital prosthesis. Improving the esthetics of eye and face improves the patient's personality, self-confidence, self-esteem, and health-related quality of life. Hence, their contribution as team-member of the oculoplasty department is significant. Ocularists work with patients with congenital anomalies of the orbit/eye and individuals who have undergone removal of the globe due to trauma, tumor, or painful blinding disease. This brief communication will outline some of their job responsibilities, interaction with patients, scope of duties, and providing modern eye care.
Concurrent branch retinal artery occlusion in central retinal vein occlusion
Authors: Goel Neha
Published: March 2021

Concurrent branch retinal artery occlusion (BRAO) and central retinal vein occlusion (CRVO) are the infrequently encountered clinical entities, with only a handful of cases elaborated in the literature. This case series describes three patients who presented with a dramatic fundus appearance that led to the diagnosis of unilateral BRAO and CRVO. Hypertension could be identified as a predisposing factor in only one patient. All three patients had relatively good visual acuity at presentation. The role of spectral-domain optical coherence tomography in confirming the simultaneous presence of BRAO is also illustrated.
Recurrent and refractory corneal perforation secondary to rheumatoid arthritis treated with infliximab
Authors: Al Saleh Ahmed , Al Saleh Abdullah S. , Al Qahtani Abdulmalik
Published: March 2021

Rheumatoid arthritis (RA) can affects many organs including the eyes. Corneal perforation in the form of peripheral ulcerative keratopathy can be debilitating and difficult to manage. A 48-year-old female with known RA presented with sudden loss of vision in her left eye, she was diagnosed with left corneal perforation secondary to severe dry eye. Penetrating keratoplasty (PKP) and punctum occlusion were done. Amniotic membrane transplant (AMT) was done 1 month later due to nonhealing epithelial defect. Her RA was clinically inactive, and no changes in her current medications were made. However, 4 months later, she presented with a second corneal perforation with melting. She had another PKP and AMT with permanent temporal tarsorrhaphy. Cyclosporine 100 mg P. O. twice daily was added, but after 5 months, she presented again with a third left corneal perforation with melting. Again, PKP and AMT with tarsorrhaphy were done, and she was started on infliximab. Since then, she had a stable graft with no further corneal perforations. In summary, patients with RA can have corneal perforations even if other signs of RA are absent. If the systemic treatment that is used to treat RA fails, one should consider using other classes of drugs, such as monoclonal antibodies (e.g., rituximab), tumor necrosis factor alpha blockers (such as infliximab or adalimumab), interleukin (IL)-1 receptor antagonists (e.g., anakinra), or IL-6 receptor antagonist (e.g., tocilizumab).
The association between diabetic retinopathy and periodontal disease
Authors: Tandon Akash , Kamath Yogish S. , Gopalkrishna Pratibha , Saokar Asmita , Prakash Sugandha , Sarpangala Shailaja B. , Bhandary Sulatha V.
Published: March 2021

PURPOSE:

The purpose of the study was to study the association between diabetic retinopathy (DR) and periodontal disease (PD) in a South Indian cohort.

METHODS:

This was a cross-sectional, observational, interdisciplinary hospital-based study wherein patients with diabetes mellitus visiting the ophthalmology department of a university teaching hospital in coastal Karnataka, south India, during the study period, were screened independently for retinopathy by an ophthalmologist and PD by a periodontal surgeon. All the patients were above 18 years of age and did not have juvenile or gestational diabetes. A total of 213 patients consented to participate in the study. The data were analyzed for association using the Chi-square test.

RESULTS:

There was a statistically significant association between the presence of DR and PD (P = 0.02). The increasing severity of DR was associated with an increase in the components of PD including plaque index (P < 0.001) and gingival index (P < 0.001).

CONCLUSION:

There is a significant association between DR and PD. The awareness of this association can aid in the screening of potentially sight-threatening retinopathy in diabetics presenting to the dental clinic with PD.
Do Saudi parents have sufficient awareness of pediatric eye diseases in Riyadh?
Authors: Al Mazrou Abdulrhman , Alsobaie Nasser A. , Abdulrahman Amro Khalid Bin , AlObaidan Omar
Published: March 2021

PURPOSE:

The current study aimed to assess Saudi parents' awareness regarding pediatric eye diseases that can be screened and treated.

METHODS:

A cross-sectional study was conducted in Riyadh, Saudi Arabia. Targeted participants were selected randomly. An online questionnaire was used for data collection. A Chi-ANOVA test was used with considering a confidence interval of 95%.

RESULTS:

Of 1500 participants, 1070 (71%) Saudi adults responded. Most of the participants' knowledge test score about eye health and care was poor (91.9%). The majority of those who had acceptable knowledge were married with 94.3%. Knowledge about the eye problem in diabetes was the highest with 82.8%, then 54.3% had acceptable knowledge about eye emergencies, general eye health with 36.5%, and 26.2% for refractive error problem, whereas knowledge about strabismus, visual deprivation, glaucoma, and eye tumors was lowest (18.9, 16.1, 10.6, and 9.6%, respectively). The most commonly reported sources of knowledge were community members. Those who were at the university level of education had a higher level of acceptable knowledge (64.4%) with a mean of 5.63. Retired participants had the highest mean level of knowledge (7.25). After that, it showed that those in the medical field had the second highest mean level of knowledge (6.55). However, students recorded the lowest mean knowledge score with 2.47.

CONCLUSION:

The current study found evidence of a lack of awareness among parents about common pediatric eye diseases and proper eye care behaviors. Therefore, awareness programs should be targeting both parents with a focus on mothers. The higher the educational level, the higher the chances of health awareness.
Rotatory atlantoaxial dislocation presenting as spinal kyphoscoliosis
Authors: Goel Atul , Vutha Ravikiran , Shah Abhidha , Rai Survendra Kumar Rajdeo
Published: March 2021

A 16-year-old male presented with primary complaint of worsening dorsal spinal kyphoscoliosis (SKS) for 3 years. More recently, he developed spasticity in legs, breathlessness on mild exertion, and sleep apneas. Apart from SKS, investigations revealed rotatory atlantoaxial dislocation. Atlantoaxial fixation resulted in rapid recovery from all symptoms including from spinal deformity. Observations in this patient suggest that rotatory dislocation can be a cause of spinal deformity.
‘Academic literacies’: sustaining a critical space on writing in academia
Authors: Lillis Theresa
Published: March 2021

In this paper, I briefly track the emergence and foci of academic literacies as a field of inquiry, summarising its contributions to understandings about writing and meaning making in academia. Writing from my specific geohistorical location in the UK, I foreground the importance of early key works that encapsulated concerns about deficit orientations to students’ language and literacy practices (e.g. Ivanič, 1998; Lea and Street,1998). I also underline the transnational dimension to the development of academic literacies which has helped drive forward intellectual debates about the relationship between academic language and literacy practices, and participation in academia. I argue that academic literacies provides an important space for critically exploring what are often taken-for-granted assumptions about the nature and value of academic writing conventions, and the ways these (both assumptions and conventions) impact on opportunities for participation in knowledge making. This critical thinking space continues to serve as an intellectual resource for researchers, teachers and students in contemporary neo-liberal higher education, where regimes of evaluation are super-normative, even in (or because of) a context of super-diversity, that is increased mobility of peoples and semiotic practices. Academic literacies as praxis necessarily involves straddling both normative and transformative orientations (Lillis and Scott, 2007) or what Hall (1992) refers to as the ‘academic’ and ‘intellectual’ dimensions to academia.
Do We Need to Implement Multi-Interval Real-Time Markets?
Authors: Biggar Darryl R. , Hesamzadeh Mohammad Reza
Published: March 2021

Many market-based power systems have implemented a form of ‘look-ahead dispatch’ which simultaneously solves for the optimal dispatch and prices over several intervals into the future. A few papers have pointed out that the dispatch outcomes which emerge from look-ahead dispatch may not be time consistent. We emphasise that this time inconsistency is not inherent in look-ahead dispatch but is a consequence of the assumption of linear cost and utility functions, which is arguably a special case. Various augmentations to the dispatch process to resolve the time inconsistency problem have been proposed, but these augmentations suffer from the drawback that they do not allow the power system to efficiently adjust to new information. We query whether it is necessary to implement multi-interval real-time markets. We show how under certain assumptions, a sequence of one-shot dispatch processes will achieve the efficient outcome.
Genetic basis of mitochondrial diseases
Authors: Gusic Mirjana , Prokisch Holger
Published: March 2021

Mitochondrial disorders are monogenic disorders characterized by a defect in oxidative phosphorylation and caused by pathogenic variants in one of over 340 different genes. The implementation of whole‐exome sequencing has led to a revolution in their diagnosis, duplicated the number of associated disease genes, and significantly increased the diagnosed fraction. However, the genetic etiology of a substantial fraction of patients exhibiting mitochondrial disorders remains unknown, highlighting limitations in variant detection and interpretation, which calls for improved computational and DNA sequencing methods, as well as the addition of OMICS tools. More intriguingly, this also suggests that some pathogenic variants lie outside of the protein‐coding genes and that the mechanisms beyond the Mendelian inheritance and the mtDNA are of relevance. This review covers the current status of the genetic basis of mitochondrial diseases, discusses current challenges and perspectives, and explores the contribution of factors beyond the protein‐coding regions and monogenic inheritance in the expansion of the genetic spectrum of disease.
50 Hz X‐Ray Diffraction Stress Analysis and Numerical Process Simulation at Laser Surface Line Hardening of Web Structures
Authors: Kiefer Dominik , Lang Florian , Simon Nicola , Beckmann Felix , Wilde Fabian , Gibmeier Jens
Published: March 2021

In situ synchrotron X‐ray diffraction experiments were carried out during laser surface line hardening of the common tempering steel AISI 4140 at beamline P05@PETRA III operated by Helmholtz‐Zentrum Geesthacht at the Deutsches Elektronen Synchrotron, Hamburg, Germany. A unique process chamber was used to investigate the phase and transverse surface stress evolution during a laser line hardening processes. Synchrotron radiation, in combination with microstrip line detectors, allows for a time resolution of 50 Hz. Specimen geometries were hardened using a high‐power diode laser under control of the surface temperature and constant laser beam feed. Herein, it is focused on web‐structured specimens in contrast to a flat geometry. The experimental results are discussed with regard to the workpiece geometry effect of the web structure dimensions on the temporal and spatial stress evolution. In addition, numerical process simulations based on the finite element method were carried out to support the drawn conclusions. The presented model is able to predict the surface transverse stresses inside the process zone center, while providing further 3D information. A heat build‐up in the web leads to a wider and deeper process zone, however, the absolute hardness increase and the transverse residual stresses at the surface center are not affected.
Suppressing Kinetic Aggregation of Non‐Fullerene Acceptor via Versatile Alloy States Enables High‐Efficiency and Stable Ternary Polymer Solar Cells
Authors: Zhang Kang‐Ning , Guo Jia‐Jia , Zhang Liu‐Jiang , Qin Chao‐Chao , Yin Hang , Gao Xing‐Yu , Hao Xiao‐Tao
Published: March 2021

Despite considerable advances devoted to improving the operational stability of organic solar cells (OSCs), the metastable morphology degradation remains a challenging obstacle for their practical application. Herein, the stabilizing function of the alloy states in the photoactive layer from the perspective of controlling the aggregation characteristics of non‐fullerene acceptors (NFAs), is revealed. The alloy‐like model is adopted separately into host donor and acceptor materials of the state‐of‐the‐art binary PM6:BTP‐4Cl blend with the self‐stable polymer acceptor PDI‐2T and small molecule donor DRCN5T as the third components, delivering the simultaneously enhanced photovoltaic efficiency and storage stability. In such ternary systems, two separate arguments can rationalize their operating principles: (1) the acceptor alloys strengthen the conformational rigidity of BTP‐4Cl molecules to restrain the intramolecular vibrations for rapid relaxation of high‐energy excited states to stabilize BTP‐4Cl acceptor. (2) The donor alloys optimize the fibril network microstructure of PM6 polymer to restrict the kinetic diffusion and aggregation of BTP‐4Cl molecules. According to the superior morphological stability, non‐radiative defect trapping coefficients can be drastically reduced without forming the long‐lived, trapped charge species in ternary blends. The results highlight the novel protective mechanisms of engineering the alloy‐like composites for reinforcing the long‐term stability of NFA‐based ternary OSCs.
Thermo‐Responsive Microcapsules with Tunable Molecular Permeability for Controlled Encapsulation and Release
Authors: Choi Ye Hun , Hwang Ji‐Su , Han Sang Hoon , Lee Chang‐Soo , Jeon Seog‐Jin , Kim Shin‐Hyun
Published: March 2021

Microcapsules with regulated transmembrane transport are of great importance for various applications. The membranes with a tunable cut‐off threshold of permeation provide advanced functionality. Here, thermo‐responsive microcapsules are designed, whose hydrogel membrane shows a tunable cut‐off threshold of permeation with temperature. To produce the microcapsules, water‐in‐oil‐in‐water (W/O/W) double‐emulsion droplets are microfluidically produced, whose oil shell contains oil‐soluble hydrogel precursor of poly(N, N‐diethylacrylamide) copolymerized with benzophenone (PDEAM‐BP). The PDEAM hydrogels, crosslinked by BP, show volume‐phase transition around 34 °C, which makes the microcapsules with the PDEAM hydrogel membrane thermo‐responsive. The microcapsules show temperature‐dependent changes in radius and membrane thickness. More importantly, the cut‐off threshold of permeation can be reversibly adjusted by temperature control as the degree of swelling decreases with temperature. This enables the molecule‐selective encapsulation and the controlled release of the encapsulants in a programmed manner by adjusting the temperature. The microcapsules can be rendered to be photo‐responsive by encapsulating photothermal polydopamine nanoparticles during the microfluidic operation, which allows the control of the degree of swelling with near‐infrared (NIR) irradiation. The thermo‐ and photo‐responsive microcapsules with a tunable cut‐off threshold are appealing as a new platform for drug carriers, microreactors, and microsensors.
Solvent Engineering of the Precursor Solution toward Large‐Area Production of Perovskite Solar Cells
Authors: Chao Lingfeng , Niu Tingting , Gao Weiyin , Ran Chenxin , Song Lin , Chen Yonghua , Huang Wei
Published: March 2021

Solar cells based on emerging organic–inorganic hybrid perovskite materials have reached certified power conversion efficiency as high as 25.5%, showing great potential in the next generation of photovoltaics toward large‐scale industrialization. The most competitive feature of perovskite solar cells (PSCs) is that the perovskite light absorber can be fabricated by a low‐cost solution method. For the solution method, the characteristics of the solvent play a key role in determining the crystallization kinetics, growth orientation, and optoelectronic properties of the perovskite film. Although significant progress has been made in the field of solvent engineering in PSCs, it is still challenging for the solution method to sustainably produce industrial‐scale PSCs for future commercialization applications. Herein, the advanced progress of solvent engineering of precursor solution in terms of coordination regulation and toxicity reduction is highlighted. The physical and chemical characteristics of different solvents in reducing the toxicity of the solvent system, regulating the coordination property of the precursor solution, controlling the film‐forming process of the perovskite film, and adjusting the photovoltaic performance of the PSC are systematically discussed. Lastly, important perspectives on solvent engineering of the perovskite precursor solution toward future industrial production of high‐performance PSCs are provided.
Porous Semiconducting Polymers Enable High‐Performance Electrochemical Transistors
Authors: Huang Lizhen , Wang Zhi , Chen Jianhua , Wang Binghao , Chen Yao , Huang Wei , Chi Lifeng , Marks Tobin J. , Facchetti Antonio
Published: March 2021

Organic polymer electrochemical transistors (OECTs) are of great interest for flexible electronics and bioelectronics applications owing to their high transconductance and low operating voltage. However, efficient OECT operation must delicately balance the seemingly incompatible materials optimizations of redox chemistry, active layer electronic transport, and ion penetration/transport. The latter characteristics are particularly challenging since most high‐mobility semiconducting polymers are hydrophobic, which hinders efficient ion penetration, hence limiting OECT performance. Here, the properties and OECT response of a series of dense and porous semiconducting polymer films are compared, the latter fabricated via a facile breath figure approach. This methodology enables fast ion doping, high transconductance (up to 364 S cm−1), and a low subthreshold swing for the hydrophobic polymers DPPDTT and P3HT, rivalling or exceeding the metrics of the relatively hydrophilic polymer, Pg2T‐T. Furthermore, the porous morphology also enhances the transconductance of hydrophilic polymers, offering a general strategy for fabricating high‐performance electrochemical transistors.
Recyclable Copper Nanoparticles‐Catalyzed Hydroboration of Alkenes and β‐Borylation of α,β‐Unsaturated Carbonyl Compounds with Bis(Pinacolato)Diboron
Authors: Shegavi Mahadev L. , Saini Suresh , Bhawar Ramesh , Vishwantha Meghana Desai , Bose Shubhankar Kumar
Published: March 2021

Nano‐ferrite‐supported Cu nanoparticles (Fe‐dopamine‐Cu NPs) catalyzed anti‐Markovnikov‐selective hydroboration of alkenes with B2pin2 is reported under mild reaction conditions. This protocol can be applied to a broad range of substrates with high functional group compatibility. In addition, we demonstrated the use of Fe‐dopamine‐Cu NPs as a catalyst for the β‐borylation of α,β‐unsaturated ketones and ester, providing alkylboronate esters in up to 98% yield. Reuse of the magnetically recyclable catalyst resulted in no significant loss of activity in up to five reaction runs for both systems.

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Palladium‐Catalyzed Thiocarbonylation of Benzyl Chlorides with Sulfonyl Chlorides for the Synthesis of Arylacetyl Thioesters
Authors: Wang Wei , Qi Xinxin , Wu Xiao‐Feng
Published: March 2021

A convenient procedure for the synthesis of thioesters has been developed via a palladium‐catalyzed thiocarbonylation of benzyl chlorides with sulfonyl chlorides. Various arylacetyl thioesters were produced in good yields by using sulfonyl chlorides as an odorless sulfur source. Furthermore, W(CO)6 exhibited dual roles as both a solid CO surrogate and reductant here.

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Soft Electronic Platforms Combining Elastomeric Stretchability and Biodegradability
Authors: Held Martin , Pichler Alexander , Chabeda Joshua , Lam Natalie , Hindenberg Philip , Romero‐Nieto Carlos , Hernandez‐Sosa Gerardo
Published: March 2021

Soft and stretchable electronic devices are expected to offer technological advances in the field of robotics, human–machine interfacing, and healthcare. Employing biodegradable elastomers, hydrogels, and nontoxic conductors would add significant value to and minimize the ecological impact of such disposable and transient electronic applications. Here, the biodegradable and photo‐crosslinkable elastomer poly(glycerol sebacic) acrylate (PGSA) is characterized for its use in soft and stretchable electronics. Its mechanical properties are investigated in terms of their chemical composition and compared to commonly used gelatin hydrogels. Furthermore, these materials are combined with interconnects made of liquid Galinstan in order to create functional substrates with certified biodegradability under ISO standards. The combination of these materials produces elastic circuit boards that act as soft platforms for body‐mounted sensors or biodegradable stretchable light‐emitting devices. These soft platforms reveal linear elongations at a break of 130% to 350% and similar moduli to nondegradable elastomers and human tissue, without any decrease in conductivity. Advanced applications in biofriendly packaging, soft robotics, and healthcare will greatly benefit from these biodegradable devices.
Lead‐Free Halide Double Perovskite Nanocrystals for Light‐Emitting Applications: Strategies for Boosting Efficiency and Stability
Authors: Tang Huidong , Xu Yanqiao , Hu Xiaobo , Hu Qing , Chen Ting , Jiang Weihui , Wang Lianjun , Jiang Wan
Published: March 2021

Lead‐free halide double perovskite (HDP) nanocrystals are considered as one of the most promising alternatives to the lead halide perovskite nanocrystals due to their unique characteristics of nontoxicity, robust intrinsic thermodynamic stability, rich and tunable optoelectronic properties. Although lead‐free HDP variants with highly efficient emission are synthesized and characterized, the photoluminescent (PL) properties of colloidal HDP nanocrystals still have enormous challenges for application in light‐emitting diode (LED) devices due to their intrinsic and surface defects, indirect band, and disallowable optical transitions. Herein, recent progress on the synthetic strategies, ligands passivation, and metal doping/alloying for boosting efficiency and stability of HDP nanocrystals is comprehensive summarized. It begins by introducing the crystalline structure, electronic structure, and PL mechanism of lead‐free HDPs. Next, the limiting factors on PL properties and origins of instability are analyzed, followed by highlighting the effects of synthesis strategies, ligands passivation, and metal doping/alloying on the PL properties and stability of the HDPs. Then, their preliminary applications for LED devices are emphasized. Finally, the challenges and prospects concerning the development of highly efficient and stable HDP nanocrystals‐based LED devices in the future are proposed.
Engineering the Activity and Stability of MOF‐Nanocomposites for Efficient Water Oxidation
Authors: Wang Yuan , Liu Borui , Shen Xiangjian , Arandiyan Hamidreza , Zhao Tingwen , Li Yibing , Garbrecht Magnus , Su Zhen , Han Li , Tricoli Antonio , Zhao Chuan
Published: March 2021

Metal–organic frameworks (MOFs) are considered to be promising candidates for electrochemical water splitting. However, most MOFs are characterized by low electronic conductivity limiting their use as bulk materials for anodes and cathodes. Furthermore, the understanding of the critical parameters controlling the activity and stability of MOF electrocatalysts is still insufficient. Herein, a systematic analysis is presented of the key structural parameters controlling the oxygen evolution reaction (OER) performance and stability of a representative family of bimetallic NiFe‐MOFs, where the role of the metal cations on the accessible active sites and intrinsic activity can be investigated independently from the crystal structure. The models and in‐depth structural and morphological characterizations reveal a hierarchy of properties affecting the OER activity with accessible sites and intrinsic activity playing a major role in the charge transfer efficiency. Optimization of these properties and addition of a conductive support substrate leads to efficient MOF‐nanocomposite electrocatalysts achieving a low overpotential of 258 mV at a current density of 10 mA cm−2 with a small Tafel slope of 49 mV dec−1 and excellent stability for more than 32 h of continuous OER in alkaline medium.
An Efficient, Sustainable Rhodium‐Catalyzed and Ionic Liquid‐Mediated C−H Thiolation and Selenation of Acetanilide with Diaryl Disulfides and Diaryl Diselenides
Authors: Rui Xiyan , Zhu Yueyue , Dai Rupeng , Huang Chaoqun , Wang Chao , Si Dongjuan , Wang Xi , Zhang Xiaoyuan , Wen Hongmei , Li Wei , Liu Jian
Published: March 2021

We established an efficient and sustainable rhodium(III)‐catalyzed and ionic liquid‐mediated C−S and C−Se formation from readily available starting material acetanilide with diaryl disulfides and diaryl diselenides. The C−H activation proceeds in ionic liquid without extra silver salt as additive, and the catalytic media can be reused for several times to accomplish the catalysts sustainable utilization. Furthermore, this synthesis protocol is suitable for a wide functional group compatibility, and the directing group can be easily removed. Most importantly it can be developed as a facile access to phenothiazine scaffold with potent biological activities, thus this strategy can be broadly applied to organic synthesis and medicinal chemistry.
Iron‐Catalyzed Oxidative Decabonylation/Radical Cyclization of Aliphatic Aldehydes with Biphenyl Isocyanides: A New Pathway For the Synthesis of 6‐Alkylphenanthridines
Authors: Luo Zaigang , Li Rui , Zhu Tao , Liu Chen‐Fu , Feng Haoran , Aboagye Nartey Kojo , Liu Qiannan , Xu Xuemei
Published: March 2021

A facile and efficient synthetic approach to C6 functionalized phenanthridines was developed. The iron catalyzed oxidative reaction undergoes subsequent decarbonylation, radical addition and cyclization processes by using aliphatic aldehydes as the alkyl radical precursors. This protocol offers a new pathway for the synthesis of 6‐alkylphenanthridines.
CPR News
Authors: Hernandez Carlos M.
Published: March 2021

A little background and context: I just retired from Fluor Corp., which is a Fortune 200 corporation in the engineering, procurement and construction industries. We had major projects underway at any one time in 60 to 80 countries around the world
Cognitive measures lacking in EHR prior to dementia or Alzheimer's disease diagnosis
Authors: Maserejian Nancy , Krzywy Henry , Eaton Susan , Galvin James E.
Published: March 2021

Introduction

The extent that cognitive measures are documented in electronic health records (EHR) is important for quality care and addressing disparities in timely diagnosis of dementia or Alzheimer's disease (AD).

Methods

Analysis of U.S. EHR data to describe the frequency and factors associated with cognitive measures prior to diagnosis of dementia (N = 111,125) or AD (N = 30,203).

Results

Only 11% of dementia patients and 24% of AD patients had a cognitive measure documented in the 5 years prior to diagnosis. Black race, older age, non‐commercial health insurance, lower mean neighborhood income, greater in‐patient stays, and fewer out‐patient visits were associated with lacking cognitive measures.

Discussion

Extensive missing cognitive data and differences in the availability of cognitive measures by race, age, and socioeconomic factors hinder patient care and limit utility of EHR for dementia research. Structured fields and prompts for cognitive data inputs at the point of care may help address these gaps.
Covalent Probes for Aggregated Protein Imaging via Michael Addition
Authors: Wan Wang , Huang Yanan , Xia Qiuxuan , Bai Yulong , Chen Yuwen , Jin Wenhan , Wang Mengdie , Shen Di , Lyu Haochen , Tang Yuqi , Dong Xuepeng , Gao Zhenming , Zhao Qun , Zhang Lihua , Liu Yu
Published: March 2021

Covalent chemical reactions to modify aggregated proteins are rare. Here, we reported covalent Michael addition can generally occur upon protein aggregation. Such reactivity was initially discovered by a bioinspired fluorescent color‐switch probe mimicking the photo‐conversion mechanism of Kaede fluorescent protein. This probe was dark with folded proteins but turned on red fluorescence (620 nm) when it non‐covalently bound to misfolded proteins. Supported by the biochemical and mass spectrometry results, the probe chemoselectively reacted with the reactive cysteines of aggregated proteins via covalent Michael addition and gradually switched to green fluorescence (515 nm) upon protein aggregation. Exploiting this Michael addition chemistry in the malachite green dye derivatives demonstrated its general applicability and chemical tunability, resulting in different fluorescence color‐switch responses. Our work may offer a new avenue to explore other chemical reactions upon protein aggregation and design covalent probes for imaging, chemical proteomics, and therapeutic purposes.
Lineare gepaarte Elektrolyse – Realisierung von 200 % Stromausbeute in stöchiometrischen Umsetzungen – die elektrochemische Bromierung von Alkenen
Authors: Strehl Julia , Abraham Marvin L. , Hilt Gerhard
Published: March 2021

Die Erzeugung von Br2durch die Oxidation von Bromid‐Ionen an der Anode und die Reduktion von molekularem Sauerstoff an der Kathode zu H2O2führte in der Summe zur Erzeugung von zwei Molekülen Br2(=Vier‐Elektronen‐Oxidation), wobei lediglich zwei Elektronen durch die Lösung geschickt wurden. Das molekulare Brom wurde zur Bromierung von Alkenen genutzt, woraufhin eine lineare gepaarte Elektrolyse verwirklicht wurde, welche Stromausbeuten von bis zu 200 % aufweist. Zudem gelangen die Diiodierung von Cyclohexen sowie die elektrophile aromatische Bromierung eines Elektronen‐reichen Aromaten mit jeweils 168 % Stromausbeute.
An Endoplasmic Reticulum Specific Pro‐amplifier of Reactive Oxygen Species in Cancer Cells
Authors: Xu Hong‐Gui , Schikora Margot , Sisa Miroslav , Daum Steffen , Klemt Insa , Janko Christina , Alexiou Christoph , Bila Galyna , Bilyy Rostyslav , Gong Wenjie , Schmitt Michael , Sellner Leopold , Mokhir Andriy
Published: March 2021

The folding and export of proteins and hydrolysis of unfolded proteins are disbalanced in the endoplasmic reticulum (ER) of cancer cells, leading to so‐called ER stress. Agents further augmenting this effect are used as anticancer drugs including clinically approved proteasome inhibitors bortezomib and carfilzomib. However, these drugs can affect normal cells, which also rely strongly on ER functions, leading, for example, to accumulation of reactive oxygen species (ROS). To address this problem, we have developed ER‐targeted prodrugs activated only in cancer cells in the presence of elevated ROS amounts. These compounds are conjugates of cholic acid with N‐alkylaminoferrocene‐based prodrugs. We confirmed their accumulation in the ER of cancer cells, their anticancer efficacy, and cancer cell specificity. These prodrugs induce ER stress, attenuate mitochondrial membrane potential, and generate mitochondrial ROS leading to cell death via necrosis. We also demonstrated that the new prodrugs are activated in vivo in Nemeth‐Kellner lymphoma (NK/Ly) murine model.
FRET Modulated Signaling: A Versatile Strategy to Construct Photoelectrochemical Microsensors for In Vivo Analysis
Authors: Ye Xiaoxue , Wang Xing , Kong Yao , Dai Mengjiao , Han Dongxue , Liu Zhihong
Published: March 2021

Microelectrode‐based electrochemical (EC) and photoelectrochemical (PEC) sensors are promising candidates for in vivo analysis of biologically important chemicals. However, limited selectivity in complicated biological systems and poor adaptability to electrochemically non‐active species restrained their applications. Herein, we propose the concept of modulating the PEC output by a fluorescence resonance energy transfer (FRET) process. The emission of energy donor was dependent on the concentration of target SO2, which in turn served as the modulator of the photocurrent signal of the photoactive material. The employment of optical modulation circumvented the problem of selectivity, and the as‐fabricated PEC microelectrode showed good stability and reproducibility in vivo. It can monitor fluctuations of SO2levels in brains of rat models of cerebral ischemia‐reperfusion and febrile seizure. More significantly, such a FRET modulated signaling strategy can be extended to diverse analytes.
Non‐Solvating and Low‐Dielectricity Cosolvent for Anion‐Derived Solid Electrolyte Interphases in Lithium Metal Batteries
Authors: Ding Jun‐Fan , Xu Rui , Yao Nan , Chen Xiang , Xiao Ye , Yao Yu‐Xing , Yan Chong , Xie Jin , Huang Jia‐Qi
Published: March 2021

Lithium (Li) metal anodes hold great promise for next‐generation high‐energy‐density batteries, while the insufficient fundamental understanding of the complex solid electrolyte interphase (SEI) is the major obstacle for the full demonstration of their potential in working batteries. The characteristics of SEI highly depend on the inner solvation structure of lithium ions (Li+). Herein, we clarify the critical significance of cosolvent properties on both Li+ solvation structure and the SEI formation on working Li metal anodes. Non‐solvating and low‐dielectricity (NL) cosolvents intrinsically enhance the interaction between anion and Li+ by affording a low dielectric environment. The abundant positively charged anion–cation aggregates generated as the introduction of NL cosolvents are preferentially brought to the negatively charged Li anode surface, inducing an anion‐derived inorganic‐rich SEI. A solvent diagram is further built to illustrate that a solvent with both proper relative binding energy toward Li+ and dielectric constant is suitable as NL cosolvent.
Bioinspired Synergistic Photochromic Luminescence and Programmable Liquid Crystal Actuators
Authors: Huang Yinliang , Bisoyi Hari Krishna , Huang Shuai , Wang Meng , Chen Xu‐Man , Liu Zhiyang , Yang Hong , Li Quan
Published: March 2021

Bioinspired smart materials with synergistic allochroic luminescence and complex deformation are expected to play an important role in many areas of science and technology. However, it is still challenging to fabricate such soft actuators with high programmability that can be manipulated in situ with high spatial resolution. Herein, we have incorporated terminally functionalized aggregation‐induced emission active tetraphenylethene derivative and photochromic spiropyran moieties into the networks of liquid crystal elastomers through covalent bonding to obtain the synergistic photochromic luminescence and programmable soft actuators. Bio‐mimic functions and light‐induced auxetic metamaterial‐like devices were shown to be feasible based on the combination of assembly and origami‐programming strategy. These bioinspired devices with synergistic photochromic luminescence and complex photodeformation abilities provide an elegant strategy to design multi‐functional liquid crystal actuators.
Ferroptosis Photoinduced by New Cyclometalated Iridium(III) Complexes and Its Synergism with Apoptosis in Tumor Cell Inhibition
Authors: Yuan Hao , Han Zhong , Chen Yuncong , Qi Fen , Fang Hongbao , Guo Zijian , Zhang Shuren , He Weijiang
Published: March 2021

Limited therapeutic efficacy to hypoxic and refractory solid tumors has hindered the practical application of photodynamic therapy (PDT). Two new benzothiophenylisoquinoline (btiq)‐derived cyclometalated IrIII complexes, IrL1 and MitoIrL2, were constructed as potent photosensitizers, with the latter being designed for mitochondria accumulation. Both complexes demonstrated a type I PDT process and caused photoinduced ferroptosis in tumor cells under hypoxia. This ferroptosis featured lipid peroxide accumulation, mitochondria shrinkage, down‐regulation of glutathione peroxidase 4 (GPX4), and ferrostatin‐1 (Fer‐1)‐inhibited cell death. Upon photoirradiation under hypoxia, mitochondria targeting MitoIrL2 caused mitochondria membrane potential (MMP) collapse, ATP production suppression, and induced cell apoptosis. The synergetic effect of ferroptosis and apoptosis causes MitoIrL2 to outperform IrL1 in inhibiting the growth of MCF‐7, PANC‐1, MDA‐MB‐231 cells and multicellular spheroids. This study demonstrates the first example of ferroptosis induced by photosensitizing IrIII complexes. Moreover, the synergism of ferroptosis and apoptosis provides a promising approach for combating hypoxic solid tumors through type I PDT processes.
Linear Paired Electrolysis—Realising 200 % Current Efficiency for Stoichiometric Transformations—The Electrochemical Bromination of Alkenes
Authors: Strehl Julia , Abraham Marvin L. , Hilt Gerhard
Published: March 2021

The generation of bromine by oxidation of bromide anions at the anode and reduction of molecular oxygen at the cathode to hydrogen peroxide resulted in the overall formation of two molecules of Br2(=four electron oxidation) by passing just two electrons through the solution. The bromine was used for the bromination of alkenes and thereby a linear paired electrolysis was attained which resulted in current efficencies of up to 200 %. Also, the diiodination of cyclohexene as well as the electrophilic aromatic bromination of an electron‐rich arene were realised both in 168 % current efficiencies.