bluuebunny/crossref_metadata_2025 huggingface dataset:
Layer‐Based Heterostructured Cathodes for Lithium‐Ion and Sodium‐Ion Batteries
Authors: Deng Ya‐Ping , Wu Zhen‐Guo , Liang Ruilin , Jiang Yi , Luo Dan , Yu Aiping , Chen Zhongwei
Published: February 2019

A critical bottleneck that hinders major performance improvement in lithium‐ion and sodium‐ion batteries is the inferior electrochemical activity of their cathode materials. While significant research progresses have been made, conventional single‐phase cathodes are still limited by intrinsic deficiencies such as low reversible capacity, enormous initial capacity loss, rapid capacity decay, and poor rate capability. In the past decade, layer‐based heterostructured cathodes acquired by combining multiple crystalline phases have emerged as candidates with a huge potential to realize performance breakthrough. Herein, recent studies on the structural properties, electrochemical behaviors, and synthesis route optimizations of these heterostructured cathodes are summarized for in‐depth discussions. Particular attention is paid to the latest mechanism discoveries and performance achievements. This review thus aims to promote a deeper understanding of the correlation between the crystal structure of cathodes and their electrochemical behavior, and offers guidance to design advance cathode materials from the aspect of crystal structure engineering.
Biomimetic Polymer Film with Brilliant Brightness Using a One‐Step Water Vapor–Induced Phase Separation Method
Authors: Zou Weizhi , Pattelli Lorenzo , Guo Jing , Yang Shijia , Yang Meng , Zhao Ning , Xu Jian , Wiersma Diederik S.
Published: February 2019

The scales of the white Cyphochilus beetles are endowed with unusual whiteness arising from the exceptional scattering efficiency of their disordered ultrastructure optimized through millions of years of evolution. Here, a simple, one‐step method based on water vapor–induced phase separation is developed to prepare thin polystyrene films with similar microstructure and comparable optical performance. A typical biomimetic 3.5 µm PS film exhibits a diffuse reflectance of 61% at 500 nm wavelength, which translates into a transport mean free path below 1 µm. A complete optical characterization through Monte Carlo simulations reveals how such a scattering performance arises from the scattering coefficient and scattering anisotropy, whose interplay provides insight into the morphological properties of the material. The potential of bright‐white coatings as smart sensors or wearable devices is highlighted using a treated 3.5 µm film as a real‐time sensor for human exhalation.
Constructing Connected Paths between UiO‐66 and PIM‐1 to Improve Membrane CO2 Separation with Crystal‐Like Gas Selectivity
Authors: Yu Guangli , Zou Xiaoqin , Sun Lei , Liu Baisong , Wang Ziyang , Zhang Panpan , Zhu Guangshan
Published: February 2019

Most metal–organic‐framework‐ (MOF‐) based hybrid membranes face the challenge of low gas permeability in CO2 separation. This study presents a new strategy of interweaving UiO‐66 and PIM‐1 to build freeways in UiO‐66‐CN@sPIM‐1 membranes for fast CO2 transport. In this strategy, sPIM‐1 is rigidified via thermal treatment to make polymer voids permanent, and concurrently polymer chains are mutually linked onto UiO‐66‐CN crystals to minimize interfacial defects. The pore chemistry of UiO‐66‐CN is kept intact in hybrid membranes, allowing full utilization of MOF pores and selective adsorption for CO2. Separation results show that UiO‐66‐CN@sPIM‐1 membranes possess exceptionally high CO2 permeability (15433.4–22665 Barrer), approaching to that of UiO‐66‐NH2 crystal (65–75% of crystal‐derived permeability). Additionally, the CO2/N2 permeation selectivity for a representative membrane (23.9–28.6) moves toward that of single crystal (24.6–29.6). The unique structure and superior CO2/N2 separation performance make UiO‐66‐CN@sPIM‐1 membranes promising in practical CO2 separations.
Artificially Reprogrammed Macrophages as Tumor‐Tropic Immunosuppression‐Resistant Biologics to Realize Therapeutics Production and Immune Activation
Authors: Li Chu‐Xin , Zhang Yu , Dong Xue , Zhang Lu , Liu Miao‐Deng , Li Bin , Zhang Ming‐Kang , Feng Jun , Zhang Xian‐Zheng
Published: February 2019

To engineer patient‐derived cells into therapy‐purposed biologics is a promising solution to realize personalized treatments. Without using gene‐editing technology, a live cell‐typed therapeutic is engineered for tumor treatment by artificially reprogramming macrophages with hyaluronic acid‐decorated superparamagnetic iron oxide nanoparticles (HIONs). This nanoparticle‐assisted cell‐reprogramming strategy demonstrates profound advantages, due to the combined contributions from the biological regulation of HIONs and the intrinsic nature of macrophages. Firstly, the reprogrammed macrophages present a substantial improvement in their innate capabilities, such as more effective tumor targeting and more efficient generation of bioactive components (e.g., reactive oxygen species, bioactive cytokines) to suppress tumor growth. Furthermore, this cell therapeutic exhibits cytostatic/proapoptotic effects specific to cancer cells. Secondly, HIONs enable macrophages more resistant to the intratumoral immunosuppressive environment. Thirdly, the macrophages are endowed with a strong ability to prime in situ protumoral M2 macrophages into antitumor M1 phenotype in a paracrine‐like manner. Consequently, a synergistic tumor‐inhibition effect is achieved. This study shows that engineering nanomaterial‐reprogrammed live cells as therapeutic biologics may be a more preferable option to the commonly used approaches where nanomaterials are administrated to induce bioresponse of certain cells in vivo.
A Bioinspired Platform for Effective Delivery of Protein Therapeutics to the Central Nervous System
Authors: Wu Di , Qin Meng , Xu Duo , Wang Lan , Liu Chaoyong , Ren Jie , Zhou George , Chen Chen , Yang Fengmei , Li Yanyan , Zhao Yuan , Huang Ruyi , Pourtaheri Sina , Kang Chunsheng , Kamata Masakazu , Chen Irvin S. Y. , He Zhanlong , Wen Jing , Chen Wei , Lu Yunfeng
Published: February 2019

Central nervous system (CNS) diseases are the leading cause of morbidity and mortality; their treatment, however, remains constrained by the blood–brain barrier (BBB) that impedes the access of most therapeutics to the brain. A CNS delivery platform for protein therapeutics, which is achieved by encapsulating the proteins within nanocapsules that contain choline and acetylcholine analogues, is reported herein. Mediated by nicotinic acetylcholine receptors and choline transporters, such nanocapsules can effectively penetrate the BBB and deliver the therapeutics to the CNS, as demonstrated in mice and non‐human primates. This universal platform, in general, enables the delivery of any protein therapeutics of interest to the brain, opening a new avenue for the treatment of CNS diseases.
Single Layer 2D Crystals for Electrochemical Applications of Ion Exchange Membranes and Hydrogen Evolution Catalysts
Authors: Perez‐Page Maria , Sahoo Madhumita , Holmes Stuart M.
Published: February 2019

The isolation of graphene is considered as the beginning of a new generation of 2D materials and 2D crystals. Because of their particular layered structure, with planar topology and a thickness from single to few atomic layers, which provide them with unique properties, 2D material are expected to have important applications in the next generation of energy systems. Electrochemical energy storage devices such as batteries or supercapacitors have already incorporated these materials as electrodes, electrocatalysts, etc. However, most of the applications reported so far use graphene based materials such as graphene oxide (GO) or reduced graphene oxide (rGO), or different 2D materials in a bulk feature. This review aims to provide an overview of the recent progress in using single layer and few layer 2D materials in electrochemical applications of ion exchange membranes and hydrogen evolution catalysts and their efficacy in these systems.
Dual Protection Layer Strategy to Increase Photoelectrode–Catalyst Interfacial Stability: A Case Study on Black Silicon Photoelectrodes
Authors: Yang Fan , Aguiar Jeffery A. , Fairchild Michael , Vakki Waltteri , Younan Sabrina , Zhou Yinghua , Zhuo Linhai , Gu Jing
Published: February 2019

Photoelectrode degradation under harsh solution conditions continues to be a major hurdle for long‐term operation and large‐scale implementation of solar fuel conversion. In this study, a dual‐layer TiO2 protection strategy is presented to improve the interfacial durability between nanoporous black silicon and photocatalysts. Nanoporous silicon photocathodes decorated with catalysts are passivated twice, providing an intermediate TiO2 layer between the substrate and catalyst and an additional TiO2 layer on top of the catalysts. Atomic layer deposition of TiO2 ensures uniform coverage of both the nanoporous silicon substrate and the catalysts. After 24 h of electrolysis at pH = 0.3, unprotected photocathodes layered with platinum and molybdenum sulfide retain only 30% and 20% of their photocurrent, respectively. At the same pH, photocathodes layered with TiO2 experience an increase in photocurrent retention: 85% for platinum‐coated photocathodes and 91% for molybdenum sulfide–coated photocathodes. Under alkaline conditions, unprotected photocathodes experience a 95% loss in photocurrent within the first 4 h of electrolysis. In contrast, TiO2‐protected photocathodes maintain 70% of their photocurrent during 12 h of electrolysis. This approach is quite general and may be employed as a protection strategy for a variety of photoabsorber–catalyst interfaces under both acidic and basic electrolyte conditions.
Nickel‐Catalyzed C(sp2)−C(sp3) Kumada Cross‐Coupling of Aryl Tosylates with Alkyl Grignard Reagents
Authors: Piontek Aleksandra , Ochędzan‐Siodłak Wioletta , Bisz Elwira , Szostak Michal
Published: February 2019

Aryl tosylates are an attractive class of electrophiles for cross‐coupling reactions due to ease of synthesis, low price, and the employment of C−O electrophiles, however, the reactivity of aryl tosylates is low. Herein, we report the Ni‐catalyzed C(sp2)−C(sp3) Kumada cross‐coupling of aryl tosylates with primary and secondary alkyl Grignard reagents. The method delivers valuable alkyl arenes by cross‐coupling with challenging alkyl organometallics possessing β‐hydrogens that are prone to β‐hydride elimination and homo‐coupling. The reaction is catalyzed by an air‐ and moisture stable‐Ni(II) precatalyst. A broad range of electronically‐varied aryl tosylates, including bis‐tosylates, underwent this transformation, and many examples are suitable at mild room temperature conditions. The combination of Ar−X cross‐coupling with the facile Ar−OH activation/cross‐coupling strategy permits for orthogonal cross‐coupling with challenging alkyl organometallics. Furthermore, we demonstrate that the method operates with TON reaching 2000, which is one of the highest turnovers observed to date in Ni‐catalyzed cross‐couplings.

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Pd‐Catalyzed Diastereoselective Intramolecular Amide α‐C−H Arylation in Sterically Hindered Monospirooxindole Motifs
Authors: Shukla Dipti , Babu Srinivasarao Arulananda
Published: February 2019

This paper reveals the diastereoselective Pd‐catalyzed intramolecular α‐C(sp3)−H arylation in amides. The intermolecular and intramolecular α‐arylation of tertiary C(sp3)−H bond of carbonyl compounds have been well documented in the literature. Nevertheless, the diastereoselective intramolecular α‐arylation of tertiary C(sp3)−H bond involving sterically hindered spirocyclic carbonyl substrates, especially amides remains a less explored task. Accordingly, we have demonstrated the diastereoselective Pd‐catalyzed intramolecular amide α‐arylation of tertiary C(sp3)−H bond using monospirooxindole‐based carboxamide substrates and construction of various sterically hindered 1,2‐bisspirooxindolopyrrolidines possessing contiguous vicinal quaternary stereocenters with high diastereoselectivity. Monospirooxindole‐based carboxamide substrates suitably positioned with an aryl halide unit and tertiary α‐C−H bond, which were required for investigating the intramolecular α‐C(sp3)−H arylation were assembled via the stereoselective [3+2] cycloaddition of azomethine ylides with acrylamides. The stereochemistry of monospirooxindoles and 1,2‐bisspirooxindolopyrrolidines possessing contiguous vicinal quaternary stereocenters was assigned based on the X‐ray structure analyses of representative compounds.

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Exploring the Biocatalytic Potential of a Self‐Sufficient Cytochrome P450 from Thermothelomyces thermophila
Authors: Fürst Maximilian J. L. J. , Kerschbaumer Bianca , Rinnofner Claudia , Migglautsch Anna K. , Winkler Margit , Fraaije Marco W.
Published: February 2019

Among nature's arsenal of oxidative enzymes, cytochrome P450s (CYPs) catalyze the most challenging reactions, the hydroxylations of non‐activated C−H bonds. Human CYPs are studied in drug development due to their physiological role at the forefront of metabolic detoxification, but their challenging handling makes them unsuitable for application. CYPs have a great potential for biocatalysis, but often lack appropriate features such as high and soluble expression, self‐sufficient internal electron transport, high stability, and an engineerable substrate scope. We have probed these characteristics for a recently described CYP that originates from the thermophilic fungus Thermothelomyces thermophila (CYP505A30), a homolog of the well‐known P450‐BM3 from Bacillus megaterium. CYP505A30 is a natural monooxygenase‐reductase fusion, is well expressed, and moderately tolerant towards temperature and solvent exposure. Although overall comparable, we found the stability of the enzyme's domains to be inverse to P450‐BM3, with a more stable reductase compared to the heme domain. After analysis of a homology model, we created mutants of the enzyme based on literature data for P450‐BM3. We then probed the enzyme variants in bioconversions using a panel of active pharmaceutical ingredients, and activities were detected for a number of structurally diverse compounds. Ibuprofen was biooxidized in a preparative scale whole cell bioconversion to 1‐, 2‐ and 3‐hydroxyibuprofen.

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Multireference Approaches to Spin‐State Energetics of Transition Metal Complexes Utilizing the Density Matrix Renormalization Group
Authors: Roemelt Michael , Pantazis Dimitrios A.
Published: February 2019

The accurate and reliable calculation of different electronic states in transition metal systems is a persistent challenge for theoretical chemistry. The widespread use of density functional theory for computing the relative energies of states with different spin in transition metal complexes not only has not discouraged, but often, owing to its limitations, has motivated the development and refinement of first‐principles wavefunction–based methods, including both single‐reference and multireference approaches. A significant boost for the latter has been the emergence of the density matrix renormalization group (DMRG) as a reliable tool in applied quantum chemistry. By enabling the use of larger active spaces than conventionally possible, DMRG has opened up areas of transition metal chemistry that were previously inaccessible to multireference approaches. The present perspective provides an overview of representative studies that make use of DMRG methods and discusses recent applications to spin‐state energetics of transition metal systems. These range from mononuclear to exchange‐coupled systems that define an important emerging field of DMRG applications. Major achievements are highlighted and potential pitfalls are identified with a view toward future methodological developments as well as extensions in the applicability of DMRG‐based approaches to problems of spin‐state energetics and exchange‐coupling in transition metal chemistry.
Various Threshold Switching Devices for Integrate and Fire Neuron Applications
Authors: Lee Donguk , Kwak Myonghoon , Moon Kibong , Choi Wooseok , Park Jaehyuk , Yoo Jongmyung , Song Jeonghwan , Lim Seokjae , Sung Changhyuck , Banerjee Writam , Hwang Hyunsang
Published: February 2019

This study demonstrates an integrate and fire (I&F) neuron using threshold switching (TS) devices to implement spike‐based neuromorphic system. An I&F neuron can be realized using the hysteric voltage switch characteristics of a TS device. To investigate the effects of various TS devices on neuron behavior, neurons are compared using three different types of TS device: NbO2‐based insulator‐to‐metal transition (IMT) device, B–Te‐based ovonic threshold switching device, and Ag/HfO2‐based atomic‐switching TS device. The results show that the off‐state resistance and switching time of the TS devices determine the leaky/nonleaky characteristics and types of activation function of neuron, respectively. In addition, it is confirmed that the threshold voltage and on‐state resistance of the TS device determine the total power consumption of neuron. Furthermore, the feasibility of the TS devices in a spiking neural network is verified by simulation program with integrated circuit emphasis (SPICE) simulation. This work indicates applicability of TS‐based I&F neuron in neuromorphic hardware application.
Polymer Nanocomposites with Interpenetrating Gradient Structure Exhibiting Ultrahigh Discharge Efficiency and Energy Density
Authors: Jiang Jianyong , Shen Zhonghui , Cai Xingke , Qian Jianfeng , Dan Zhenkang , Lin Yuanhua , Liu Bilu , Nan Ce‐Wen , Chen Longqing , Shen Yang
Published: February 2019

Poly(vinylidene fluoride) (PVDF) based polymer nanocomposites with high‐permittivity nanofillers exhibit outstanding dielectric energy storage performance due to their high dielectric permittivities and breakdown strength. However, their discharge efficiency is relatively low (usually lower than 70%), which limits their practical applications. Here, polymer nanocomposites with a novel interpenetrating gradient structure are designed and demonstrated by cofilling a PVDF matrix with barium zirconate titanate nanofibers and hexagonal boron nitride nanosheets via modified nonequilibrium processing. The interpenetrating gradient structure is highly effective in breaking the trade‐off between discharge energy density and efficiency of the corresponding nanocomposite, as indicated by the concomitantly enhanced discharge energy density (U
e ≈ 23.4 J cm−3) and discharge efficiency (η ≈ 83%). The superior performance is primarily attributed to the rational distribution of nanofillers in the polymer matrix, which raises the height of the potential barrier for charge injection at the dielectric/electrode interface, suppresses electric conduction and contributes to enhanced apparent breakdown strength. Meanwhile, the gradient configuration allows higher volume fraction of high‐permittivity nanofillers without compromising the breakdown strength, leading to higher electric polarization compared with the random configuration. This work provides new opportunities to PVDF‐based polymer nanocomposites with high energy density and discharge efficiency for capacitive energy storage applications.
The Role of Antireflective Coating CYTOP, Immersion Oil, and Sensitizer Selection in Fabricating a 2.3 V, 10% Power Conversion Efficiency SSM‐DSC Device
Authors: Cheema Hammad , Delcamp Jared H.
Published: February 2019

Sequential series multijunction dye‐sensitized solar cells (SSM‐DSCs) can power solar‐to‐fuel processes with a single illuminated area device. Dye selection and strategies limiting photon losses are critical in SSM‐DSC devices for higher performance systems. Herein, an efficient and readily applicable spin coating protocol on glass surfaces with an antireflective fluoropolymer (CYTOP) is applied to an SSM‐DSC architecture. Combining CYTOP with the use of an immersion oil between glass spacers in a three subcell SSM‐DSC with judiciously selected TiO2 photoanode sensitizers and thicknesses, an overall power conversion efficiency (PCE) of 10.1% is obtained with an output of 2.3 V. Without external bias, this SSM‐DSC configuration shows an impressive overall solar‐to‐fuel conversion efficiency of 6% when powering IrO2 and Au2O3 electrocatalysts for CO2 and H2O to CO and H2 conversion in aqueous solution. The role of CYTOP, immersion oil, sensitizer selection, and film thickness on SSM‐DSC devices is discussed along with the stability of this system.
The Standardized Video Interview: How Does It Affect the Likelihood to Invite for a Residency Interview?
Authors: Husain Abbas , Li Ida , Ardolic Brahim , Bond Michael C. , Shoenberger Jan , Shah Kaushal H. , Chung Arlene S. , Dermark Jeffrey Van , Bronner Jonathan M. , White Melissa , Taylor Todd , Cygan Lukasz , Caputo William , Silver Matthew , Krauss William C. , Egan Daniel J. , Weizberg Moshe
Published: February 2019

Background

The Association of American Medical Colleges instituted a standardized video interview (SVI) for all applicants to emergency medicine (EM). It is unclear how the SVI affects a faculty reviewer's decision on likelihood to invite an applicant (LTI) for an interview.

Objectives

The objective was to determine whether the SVI affects the LTI.

Methods

Nine Accreditation Council of Graduate Medication Education (ACGME)‐accredited EM residency programs participated in this prospective, observational study. LTI was defined on a 5‐point Likert scale as follows: 1 = definitely not invite, 2 = likely not invite, 3 = might invite, 4 = probably invite, 5 = definitely invite. LTI was recorded at three instances during each review: 1) after typical screening (blinded to the SVI), 2) after unblinding to the SVI score, and 3) after viewing the SVI video.

Results

Seventeen reviewers at nine ACGME‐accredited residency programs participated. We reviewed 2,219 applications representing 1,424 unique applicants. After unblinding the SVI score, LTI did not change in 2,065 (93.1%), increased in 85 (3.8%) and decreased in 69 (3.1%; p = 0.22). In subgroup analyses, the effect of the SVI on LTI was unchanged by United States Medical Licensing Examination score. However, when examining subgroups of SVI scores, the percentage of applicants in whom the SVI score changed the LTI was significantly different in those that scored in the lower and upper subgroups (p < 0.0001). The SVI video was viewed in 816 (36.8%) applications. Watching the video did not change the LTI in 631 (77.3%); LTI increased in 106 (13.0%) and decreased in 79 (9.7%) applications (p = 0.04).

Conclusions

The SVI score changed the LTI in 7% of applications. In this group, the score was equally likely to increase or decrease the LTI. Lower SVI scores were more likely to decrease the LTI than higher scores were to increase the LTI. Watching the SVI video was more likely to increase the LTI than to decrease it.
Agglomerate breakage and adhesion upon impact with complex‐shaped particles
Authors: Tamadondar Mohammad R. , de Martín Lilian , Rasmuson Anders
Published: February 2019

Understanding the breakage and adhesion of an agglomerate upon collision with a target particle is a primary step to fathom the adhesive mixing process. While the effect of several variables, such as collision velocity and particle interface energy, on collision behavior has been explored, the effects of target particle morphology have yet to be revealed. In this work, we generate three‐dimensional particles with controllable shape and texture using Fourier harmonics and, using the discrete element method, we examine the collision of an agglomerate that impacts each target particle. Results show that the agglomerate breakage depends on the local curvature in the impact zone. We observe that the asperity and elongation factors of the target particle largely contribute to the extent of the deposition of fine particles and the size and number of generated fragments after impact, respectively. These results reveal the large potential error when approximating real particles as smooth spheres in fragmentation studies.
High energy requirements and water throughput of adult Shuar forager‐horticulturalists of Amazonian Ecuador
Authors: Christopher Lauren , Madimenos Felicia C. , Bribiescas Richard G. , Urlacher Samuel S. , Snodgrass James J. , Sugiyama Lawrence S. , Pontzer Herman
Published: February 2019

Objectives

We measured total energy expenditure (TEE; kcal/d) and water throughput (L/d) among Shuar forager‐horticulturalists from Amazonian Ecuador to compare their daily energy and water demands to adults in other small‐scale and industrialized populations.

Methods

TEE and water throughput were measured using the doubly labeled water method among 15 Shuar adults (eight women, seven men; age range 18‐60 years) living in a relatively remote village. We used multiple regression to assess the effects of anthropometric variables (body size, fat free mass, age, and sex) on TEE and water throughput. We also compared Shuar TEE and water throughput to those of other small‐scale and industrialized societies.

Results

TEE among Shuar adults (men: 4141 ± 645 kcal/d, women: 2536 ± 281 kcal/d) was most strongly correlated with fat free mass. Estimated physical activity levels (PAL) calculated as (TEE/estimated BMR), were greater for men (2.34 ± 0.29) than women (1.83 ± 0.14, P < 0.001). Water throughput was also greater among Shuar men (9.37 ± 2.34 L/d) than women (4.76 ± 0.36 L/d, P < 0.001). Shuar TEE and water throughput were elevated compared to adults in industrialized populations.

Discussion

TEE and PAL of Shuar men are among the highest recorded during normal daily life, and likely reflect both high levels of physical activity and cultural dietary practices. Drinking large amounts of chicha, a traditional carbohydrate‐rich drink made from manioc, likely contributes to the high levels of water throughput among Shuar men, and may contribute to elevated TEE.
Disruption of the PTHLH regulatory landscape results in features consistent with hyperparathyroid disease
Authors: Deshwar Ashish R. , Spielmann Malte , Vi Lisa , Mendoza‐Londono Roberto , Dupuis Lucie , Stimec Jennifer , Howard Andrew , Harrington Jennifer , Kannu Peter
Published: February 2019

Parathyroid hormone like hormone (PTHLH) signaling is essential for the proper formation of bone and its elevation or disruption has been directly implicated in several different skeletal dysplasias. We report a patient with a 2.802 Mb deletion upstream of the PTHLH coding sequence who presents with multiple fractures, metaphyseal changes, and overall features consistent with hyperparathyroid like disease. Analysis of the deleted region revealed the loss of putative regulatory regions adjacent to PTHLH and the possible gain of a limb enhancer. Furthermore, PTHLH expression appeared to be mis‐regulated in fibroblasts derived from the patient. Altogether, we find that the disruption of the regulatory landscape of PTHLH likely results in its inappropriate expression and this novel clinical presentation.
A De novo HDAC2 variant in a patient with features consistent with Cornelia de Lange syndrome phenotype
Authors: Wagner Victoria F. , Hillman Paul R. , Britt Allison D. , Ray Joseph W. , Farach Laura S.
Published: February 2019

Cornelia de Lange syndrome (CdLS) is an autosomal dominant genetic disorder caused by pathogenic variants in NIPBL, RAD21, SMC3, HDAC8, or SMC1A; all of which code for proteins that are components of, or interact with, the cohesin complex. Despite the identification of multiple genes associated with CdLS, over 25% of individuals strongly suspected to have CdLS have negative genetic testing, indicating that there are additional genes associated with the condition. HDAC2 codes for histone deacetylase 2 (HDAC2) and, like HDAC8, is a Class 1 histone deacetylase. We present a patient with a novel de novo variant in HDAC2 with many clinical features consistent with CdLS including severe developmental delay, limb abnormalities, congenital heart defect, cryptorchidism and hypoplastic genitalia, growth retardation, and characteristic craniofacial features. Although variants in HDAC2 are not currently associated with human disease, the variant identified in this patient is within a highly conserved amino acid residue and has not been observed in healthy populations. This information, along with the patient's clinical presentation and the functional similarity between the HDAC2 and HDAC8 proteins, suggests that HDAC2 should be further investigated as a candidate gene for CdLS or a CdLS‐like syndrome.
Metabolic patterns across core features in dementia with lewy bodies
Authors: Morbelli Silvia , Chincarini Andrea , Brendel Matthias , Rominger Axel , Bruffaerts Rose , Vandenberghe Rik , Kramberger Milica G. , Trost Maja , Garibotto Valentina , Nicastro Nicolas , Frisoni Giovanni B. , Lemstra Afina W. , van der Zande Jessica , Pilotto Andrea , Padovani Alessandro , Garcia‐Ptacek Sara , Savitcheva Irina , Ochoa‐Figueroa Miguel A. , Davidsson Annette , Camacho Valle , Peira Enrico , Arnaldi Dario , Bauckneht Matteo , Pardini Matteo , Sambuceti Gianmario , Aarsland Dag , Nobili Flavio
Published: February 2019

Objective

To identify brain regions whose metabolic impairment contributes to dementia with Lewy bodies (DLB) clinical core features expression and to assess the influence of severity of global cognitive impairment on the DLB hypometabolic pattern.

Methods

Brain fluorodeoxyglucose positron emission tomography and information on core features were available in 171 patients belonging to the imaging repository of the European DLB Consortium. Principal component analysis was applied to identify brain regions relevant to the local data variance. A linear regression model was applied to generate core‐feature–specific patterns controlling for the main confounding variables (Mini‐Mental State Examination [MMSE], age, education, gender, and center). Regression analysis to the locally normalized intensities was performed to generate an MMSE‐sensitive map.

Results

Parkinsonism negatively covaried with bilateral parietal, precuneus, and anterior cingulate metabolism; visual hallucinations (VH) with bilateral dorsolateral–frontal cortex, posterior cingulate, and parietal metabolism; and rapid eye movement sleep behavior disorder (RBD) with bilateral parieto‐occipital cortex, precuneus, and ventrolateral–frontal metabolism. VH and RBD shared a positive covariance with metabolism in the medial temporal lobe, cerebellum, brainstem, basal ganglia, thalami, and orbitofrontal and sensorimotor cortex. Cognitive fluctuations negatively covaried with occipital metabolism and positively with parietal lobe metabolism. MMSE positively covaried with metabolism in the left superior frontal gyrus, bilateral–parietal cortex, and left precuneus, and negatively with metabolism in the insula, medial frontal gyrus, hippocampus in the left hemisphere, and right cerebellum.

Interpretation

Regions of more preserved metabolism are relatively consistent across the variegate DLB spectrum. By contrast, core features were associated with more prominent hypometabolism in specific regions, thus suggesting a close clinical–imaging correlation, reflecting the interplay between topography of neurodegeneration and clinical presentation in DLB patients. Ann Neurol 2019;85:715–725
Physicochemical and mechanical degradation of polyamide 11 induced by hydrolysis and thermal aging
Authors: Maïza S. , Lefebvre X. , Brusselle‐Dupend N. , Klopffer M.‐H. , Cangémi L. , Castagnet S. , Grandidier J.‐C.
Published: February 2019

This article deals with the effect of both temperature and water activity on polyamide 11 physicochemical and mechanical properties. The purpose of this work is to describe the ductile–brittle transition of polyamides during aging in a wet environment using a mechanical behavior model. For that it is necessary to make physicochemical analyzes (DSC, FTIR, GPC, viscosity) and mechanical tests (uniaxial tensile test and dynamic mechanical thermal analysis). All of these tests were performed on unaged samples and on aged samples for until 60 days. Two types of aging conditions were performed: In water in an acidic medium at temperature, and in purely thermal conditions in a neutral environment. Changes in mechanical properties with aging were observed in the polymer and were correlated to morphological changes deduced from the physicochemical characterizations. An increase of the second yield stress related to the recrystallization and a decrease of the strain at break due to the decrease of the molecular weight were observed during aging. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47628.
Electromagnetic interference shielding behavior of chemically and thermally reduced graphene based multifunctional polyurethane nanocomposites: A comparative study
Authors: Bansala Taruna , Joshi Mangala , Mukhopadhyay Samrat
Published: February 2019

This article presents the effect of exfoliation, dispersion, and electrical conductivity of graphene sheets onto the electrical, electromagnetic interference (EMI) shielding, and gas barrier properties of thermoplastic polyurethane (TPU) based nanocomposite films. The chemically reduced graphene (CRG) and thermally reduced/annealed graphene (TRG) having Brunauer–Emmett–Teller surface areas of 18.2 and 159.6 m2/g, respectively, when solution blended with TPU matrix using N,N‐dimethylformamide as a solvent. Graphene sheets based TPU nanocomposites have been evaluated and compared for EMI shielding in Ku band, electrical conductivity, and gas barrier property. TRG/TPU nanocomposite films showed excellent gas barrier against N2 gas as compared to CRG/TPU. The EMI shielding effectiveness for neat CRG and TRG graphene sheets is found to be −80, −45 dB, respectively, at 2 mm thickness. The EMI shielding data revealed that TRG/TPU nanocomposites showed better shielding at lower concentration (10 wt %), while CRG displayed better attenuation at higher concentrations. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47666.
Influence of the processing variables on the microstructure and properties of gelatin‐based scaffolds by freeze‐drying
Authors: Perez‐Puyana V. , Felix M. , Romero A. , Guerrero A.
Published: February 2019

In the last few years, the field of tissue engineering has suffered an exponential growth, and although it is true that the processing parameters affect the properties of the scaffolds, only a few studies have investigated that statement. For that reason, the influence of different parameters involved in the freeze‐drying process (container, freezing temperature, pH, and solvent used) on the mechanical and structural properties of gelatin‐based scaffolds was analyzed in this study. Thus, rheological measurements and porosity analyses were performed to evaluate the scaffolds obtained. Results indicate that the parameters evaluated modify the mechanical properties of the scaffold, highlighting the option of a plastic mold to contain an acidic protein solution produced using a weak acid (acetic acid) at low concentration (0.05 M) as solvent. On the contrary, only the pH and the freezing temperature led to significant differences in the porosity of these scaffolds, obtaining values higher than 95% for all the systems studied. These results are useful to demonstrate that the control of the different parameters implied in the processing technique allows designing a scaffold with specific properties suitable for different applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47671.
Compatibilizing effects for semicrystalline polymer‐infiltrated amorphous polymer matrix: Mechanical (toughness), thermal, and morphological behavior of compatibilized polypropylene/polycarbonate blends
Authors: Jang Keon‐Soo
Published: February 2019

Polycarbonates (PCs) have been extensively blended with polyolefins such as polypropylene (PP) due to pecuniary advantages. Although the toughness of a pristine PC matrix has been examined, limited works have investigated the toughness of heterogeneous PC/PP blend systems, focusing merely on PC‐dispersed PP matrices. In this study, the mechanical/thermal properties of PP‐dispersed PC matrix (PC‐rich phase) were examined by using potential compatibilizers: poly(maleic anhydride‐alt‐α‐olefin) (OM), ethylene‐co‐acrylic acid (EA), and cyclic olefin copolymer. The incorporation of 0.5–5.0 phr of compatibilizers (OM and EA) into PC substantially enhanced the toughness of PC/PP15 blends according to four different testing methods. The highest toughness was obtained with 0.5 phr of OM and EA. The compatibilized blends displayed enhanced various thermal properties such as glass transition temperatures, heat deflection temperature, and degradation point, due to the compatibilizing effect. Moreover, 0.5 phr of compatibilizers (OM and EA) were determined as the most effective concentration in terms of toughness and most properties, without compromising strengths and moduli. The morphology of PP‐dispersed PC matrix (crystalline polymer‐infiltrated amorphous polymer matrix) differed from that of PC‐dispersed PP matrix. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47684.
Strong Inhibitory Effects of Antisense Probes on Gene Expression through Ultrafast RNA Photocrosslinking
Authors: Fujimoto Kenzo , Yang‐Chun Hung , Nakamura Shigetaka
Published: February 2019

We have reported the photochemical regulation of the intracellular antisense effect of antisense probes containing a photo‐responsive artificial nucleic acid, 3‐cyanovinylcarbazole nucleoside (CNVK). Here we focus on the importance of the photocrosslinking rate on the inhibitory effect on gene expression using photocrosslinkable antisense probes (pcASOs). The inhibitory effect of pcASOs on GFP gene expression was dependent on the photocrosslinking rate of 3‐cyanovinylcarbazole with d‐threoninol (CNVD), CNVK, or psoralen. The ultrafast RNA photocrosslinking induced the formation of a thermally irreversible covalent bond between pcASOs and the target RNA. These ASOs strongly inhibited gene expression only when the photocrosslinking rate was faster than the random walk of branch migration. In addition, pcASOs containing CNVD or CNVK targeted the RNAs with secondary structures. These results indicate the regulatory effect of photocrosslinker and photoirradiation energy using pcASOs on the gene expression level.
Periodic Mesoporous Organosilicas as Efficient Nanoreactors in Cascade Reactions Preparing Cyclopropanic Derivatives
Authors: Huo Hang , Jiang Yanqiu , Zhao Tingting , Wang Junlei , Li Defeng , Xu Xianzhu , Lin Kaifeng
Published: February 2019

In this work, three organosilica precursors functionalized with carbamate moieties were synthesized by condensing of 3‐isocyanatopropyltriethoxysilane and coupling regents of either hydroquinone (HQ), bisphenol A (BPA), or 1,1′‐bi‐2‐naphthol (BN). These organosilica precursors were covalently bonded in the framework of periodic mesoporous organosilicas by co‐condensation and hydrolysis with tetraethyl orthosilicate (TEOS) under hydrothermal treatment. The compositions and physical properties were characterized with FTIR, XRD, thermogravimetric/differential thermal analysis (TG/DTA), 29Si NMR, 13C NMR spectroscopies, SEM, TEM, and BET technologies. These characterizations suggest that three different structures were formed as the result of different sizes and compositions of the organosilica precursors. The three mesoporous organosilicas were applied as heterogeneous catalysts in the one‐pot cascade Knoevenagel and Michael cyclopropanic reactions for the synthesis of cyclopropanic derivatives and showed excellent activity and selectivity. The highest conversion was obtained with mesoporous catalyst (MC)‐HQ owing to its ordered mesostructure, highest surface area, and weakest stereo effect of the organic linking groups compared with MC‐BAP and MC‐BN. This methodology employed cheaper and more easily obtainable raw materials as reagents over the traditional alkene additive system and these heterogeneous catalysts exhibit superior performance and recyclability than typical homogeneous organic catalysts.
Thermo‐chemical conversion of biomass and upgrading to biofuel: The Thermo‐Catalytic Reforming process – A review
Authors: Schmitt Nina , Apfelbacher Andreas , Jäger Nils , Daschner Robert , Stenzel Fabian , Hornung Andreas
Published: February 2019

Thermo‐catalytic reforming (TCR®) is a promising conversion technology for the production of liquid bio‐fuels. The process is a proven opportunity to convert biological wastes and residues into hydrogen‐rich syngas, high‐quality oil, and char without volatiles. Bio‐oil produced from TCR® has a high carbon content, low water content, low oxygen content, and a high heating value; it is therefore directly applicable as feed in boilers or as blend in dual fuel engines. A feasible opportunity for using bio‐oil in automotive combustion engines is a further upgrade step to bio‐fuel by hydrogenation. During this hydrotreatment, heterogeneous atoms like sulfur, nitrogen, and oxygen are removed or substituted with hydrogen. Fraunhofer UMSICHT already produces gasoline and diesel that comply with European fuel standards EN 228 and EN 590, using different catalysts like NiMo/Al2O3, CoMo/Al2O3, and Ru/C for hydrogenation at 643 K and a constant hydrogen pressure of 14 MPa. Various hydrocarbons and benzene derivatives are verified after hydrotreating. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.
Amerikanische Policy‐Forschung, Komplexität und die Krise des Regierens: Zur gesellschaftlichen Einbettung sozialwissenschaftlicher Begriffsbildung
Authors: Leendertz Ariane
Published: February 2019

The American Policy Sciences, Complexity and the Crisis of Government: On the Social Embeddedness of Concept Formation in the Social Sciences. By analyzing debates about social “complexity” in the American policy sciences and in intellectual discourse of the 1970s, this article draws attention to the social embeddedness of concept formation and theory building in the social sciences. In the 1970s, a new concept of social “complexity” emerged in the social sciences, when scholars transferred and adapted elements of complexity theory from mathematics, computer science, cybernetics, and general systems theory to refine social theory. The article analyzes the context and conditions in which this transfer occurred. It shows that the scholarly debates about social complexity were entwined with broader public‐political discourses, dealing in particular with the challenges of government and public policy in the advanced Western democracies. The discourse on complexity among social scientists had additional layers of meaning: even in academic discourse, “complexity” was also used as a buzzword and as a metaphor.
Establishing synthesis pathway‐host compatibility via enzyme solubility
Authors: Amin Sara A. , Endalur Gopinarayanan Venkatesh , Nair Nikhil U. , Hassoun Soha
Published: February 2019

Current pathway synthesis tools identify possible pathways that can be added to a host to produce the desired target molecule through the exploration of abstract metabolic and reaction network space. However, not many of these tools explore gene‐level information required to physically realize the identified synthesis pathways, and none explore enzyme‐host compatibility. Developing tools that address this disconnect between abstract reactions/metabolic design space and physical genetic sequence design space will enable expedited experimental efforts that avoid exploring unprofitable synthesis pathways. This work describes a workflow, termed Probabilistic Pathway Assembly with Solubility Confidence Scores (ProPASS), which links synthesis pathway construction with the exploration of the physical design space as imposed by the availability of enzymes with predicted characterized activities within the host. Predicted protein solubility propensity scores are used as a confidence level to quantify the compatibility of each pathway enzyme with the host Escherichia coli (E. coli). This study also presents a database, termed Protein Solubility Database (ProSol DB), which provides solubility confidence scores in E. coli for 240,016 characterized enzymes obtained from UniProtKB/Swiss‐Prot. The utility of ProPASS is demonstrated by generating genetic implementations of heterologous synthesis pathways in E. coli that target several commercially useful biomolecules.
Model‐based optimization of antibody galactosylation in CHO cell culture
Authors: Kotidis Pavlos , Jedrzejewski Philip , Sou Si Nga , Sellick Christopher , Polizzi Karen , del Val Ioscani Jimenez , Kontoravdi Cleo
Published: February 2019

Exerting control over the glycan moieties of antibody therapeutics is highly desirable from a product safety and batch‐to‐batch consistency perspective. Strategies to improve antibody productivity may compromise quality, while interventions for improving glycoform distribution can adversely affect cell growth and productivity. Process design therefore needs to consider the trade‐off between preserving cellular health and productivity while enhancing antibody quality. In this work, we present a modeling platform that quantifies the impact of glycosylation precursor feeding – specifically that of galactose and uridine – on cellular growth, metabolism as well as antibody productivity and glycoform distribution. The platform has been parameterized using an initial training data set yielding an accuracy of ±5% with respect to glycoform distribution. It was then used to design an optimized feeding strategy that enhances the final concentration of galactosylated antibody in the supernatant by over 90% compared with the control without compromising the integral of viable cell density or final antibody titer. This work supports the implementation of Quality by Design towards higher‐performing bioprocesses.
Impact of protein blocking on enzymatic saccharification of bagasse from sugarcane clones
Authors: Ázar Rafaela I. S. Ladeira , Morgan Túlio , Barbosa Márcio H. P. , Guimarães Valéria M. , Ximenes Eduardo , Ladisch Michael
Published: February 2019

Lignin plays an important functional and structural role in plants, but also contributes to the recalcitrance of lignocellulosic biomass to hydrolysis. This study addresses the influence of lignin in hydrolysis of sugarcane bagasse from conventional bred lines (UFV260 and UFV204) that were selected from 432 field‐grown clones. In addition to higher sugar production, bagasse clone UFV204 had a small, but statistically significant, lower insoluble lignin content compared with clone UFV260 (15.5% vs, 16.6%) and also exhibited a significantly higher cellulose conversion to glucose (81.3% vs. 63.3%) at a cellulase loading of 5 (filter paper unit) FPU/g of glucan or 3 FPU/g total solids for liquid hot water pretreated bagasse (200°C, 10 min). The enzyme loading was further decreased by 50% to 2.5 FPU/g glucan and resulted in a similar glucan conversion (88.5%) for clone UFV204 when the bagasse was preincubated with bovine serum albumin at pH 4.8 and nonproductive binding of cellulase components was blocked. Comparison of Langmuir adsorption isotherms and differential adsorption of the three major cellulolytic enzyme components endoglucanase, cellobiohydrolase, and β‐glucosidase help to explain differences due to lignin content.