bluuebunny/crossref_metadata_2025 huggingface dataset:
Van der Waals Epitaxy of Horizontally Orientated Bismuth Iodide/Silicon Heterostructure for Nonvolatile Resistive‐Switching Memory with Multistate Data Storage
Authors: Li Chia‐Shuo , Kuo Sheng‐Wen , Wu Yu‐Tien , Chang Po‐Hang , Ni I‐Chih , Chen Mei‐Hsin , Wu Chih‐I
Published: July 2020

The film quality of insulators significantly affects performance of resistive random‐access memories (RRAMs), particularly in current leakage and degradation. In this study, a facile and practical method is employed to achieve the van der Waals epitaxy of bismuth iodide (BiI3) on silicon by using a self‐assembled monolayer of octadecyltrichlorosilane (OTS) as a buffer layer. The BiI3layer is compact and has high crystallinity, a pinhole‐free, and compact surface; every BiI3crystal is horizontally aligned with OTS–Si substrate. The RRAMs with the Si++/OTS/BiI3/Au structure exhibit excellent resistive switching properties with a very high on/off ratio of 109, long‐term stability for data retention, high endurance in write–erase cycles, and multistate information storage capacity. The crystal orientation, anisotropic carrier transport, morphology, deposition rate, and roughness considerably influence the resistive switching results. These are thoroughly investigated by analyzing the current–voltage characteristics at various temperatures, scanning electron microscope, atomic force microscope, X‐ray photoemission spectroscopy, and X‐ray diffraction patterns. It is proposed that the resistive switching mechanisms is caused by the iodine ion migration, which changes the valence charge of bismuth. This leaves a partially formed conductive metallic bismuth filament in the BiI3layer under the electrical field that enables multistate data storage.
Advancing Metal‐Organic Frameworks toward Smart Sensing: Enhanced Fluorescence by a Photonic Metal‐Organic Framework for Organic Vapor Sensing
Authors: Olorunyomi Joseph F. , Sadiq Muhammad M. , Batten Michael , Konstas Kristina , Chen Dehong , Doherty Cara M. , Caruso Rachel A.
Published: July 2020

Polymer‐based colloidal crystals are promising materials for the enhancement of fluorescent emissions, however, due to limited porosity, they are not yet readily deployed in chemical vapor sensing. On the contrary, metal‐organic frameworks (MOFs) are highly porous with an exceptional ability to detect a wide range of toxic chemicals through fluorescence. Here, it is shown for the first time how enhanced fluorescence of a fluorophore can be achieved by incorporating a fluorescent dye into a template‐free periodically structured MOF film. A 200‐fold fluorescent intensity amplification is observed when Nile red (NR) dye is adsorbed on zeolitic imidazolate framework‐8 (ZIF‐8) particles and is then assembled into a colloidal crystal film (NR∼ccZIF‐8) when compared to the disordered film (NR∼ZIF‐8). The NR∼ccZIF‐8 film shows a response to 100 ppm of acetone vapor at room temperature with a detection limit of 60 ppm. The NR∼ccZIF‐8 film shows more than 40 times higher sensitivity to toluene vapor at 770 ppm than NR adsorbed on polystyrene particles forming a colloidal crystal film. From this study, it is expected that MOFs will play a role in the future development of smart sensors for chemical and biomedical applications.
Isolated FeN4 Sites for Efficient Electrocatalytic CO2 Reduction
Authors: Li Xiaogang , Xi Shibo , Sun Libo , Dou Shuo , Huang Zhenfeng , Su Tan , Wang Xin
Published: July 2020

The construction of isolated metal sites represents a promising approach for electrocatalyst design toward the efficient electrochemical conversion of carbon dioxide (CO2). Herein, Fe‐doped graphitic carbon nitride is rationally prepared by a simple adsorption method and is used as template to construct isolated FeN4 sites through a confined pyrolysis strategy, which avoids the agglomeration of metal atoms to particles during the synthesis process and thus provides abundant active sites for the CO2 reduction reaction. The isolated FeN4 sites lower the energy barrier for the key intermediate in the CO2 reduction process, leading to the enhanced selectivity for CO production with a faradaic efficiency of up to 93%.
Predicting activity coefficients with the Debye–Hückel theory using concentration dependent static permittivity
Authors: Lei Qun , Peng Baoliang , Sun Li , Luo Jianhui , Chen Yuan , Kontogeorgis Georgios M. , Liang Xiaodong
Published: July 2020

In order to investigate the impacts of a concentration dependent static permittivity in the Debye–Hückel theory, two electrostatic Helmholtz free energy models and four activity coefficient models, with the ion‐solvent interactions naturally included, are derived under different assumptions. The effects of static permittivity and model parameters are analyzed by predicting the mean ionic activity coefficients. It is found out that it is reasonable to assume a constant static permittivity in deriving the electrostatic Helmholtz free energy model but it is highly recommended to take the concentration dependence of static permittivity into account in subsequent calculations of thermodynamic properties. The activity coefficient model derived in this way accurately predicts the mean ionic activity coefficients of the investigated systems up to 0.1 mol/kg H2O, which indicates that the size parameters in the Debye–Hückel theory might be determined in advance before it is integrated into a more complete thermodynamic model.
Sonochemistry and Copper Catalysis: An Efficient Duo in the Synthesis of Chalcogenylindolizines
Authors: Penteado Filipe , Bettanin Luana , Machado Kethelyn , Perin Gelson , Alves Diego , Lenardão Eder J.
Published: July 2020

Herein, we describe an efficient and selective Cu‐catalyzed C−H bond chalcogenation of the indolizine core, in the presence of DMSO and applying ultrasound irradiation as an alternative energy source. Under the optimal conditions, 3‐sulfanylindolizines (16 examples) were prepared in moderate to good yields starting from diorganyl disulfides and 2‐arylindolizines. When diphenyl diselenide was used, 1,3‐bis(selanyl) indolizines (4 examples) were exclusively obtained in very good yields. The use of ultrasound irradiation makes the reaction faster and more selective when compared to conventional heating.
Quality of life and caregiver burden in familial frontotemporal lobar degeneration: Analyses of symptomatic and asymptomatic individuals within the LEFFTDS cohort
Authors: Gentry Melanie T. , Lapid Maria I. , Syrjanen Jeremy , Calvert Kendrick , Hughes Samantha , Brushaber Danielle , Kremers Walter , Bove Jessica , Brannelly Patrick , Coppola Giovanni , Dheel Christina , Dickerson Bradley , Dickinson Susan , Faber Kelley , Fields Julie , Fong Jamie , Foroud Tatiana , Forsberg Leah , Gavrilova Ralitza , Gearhart Deb , Ghoshal Nupur , Goldman Jill , Graff‐Radford Jonathan , Graff‐Radford Neill , Grossman Murray , Haley Dana , Heuer Hilary , Hsiung Ging‐Yuek , Huey Edward , Irwin David , Jones David , Jones Lynne , Kantarci Kejal , Karydas Anna , Knopman David , Kornak John , Kramer Joel , Kukull Walter , Lucente Diane , Lungu Codrin , Mackenzie Ian , Manoochehri Masood , McGinnis Scott , Miller Bruce , Pearlman Rodney , Petrucelli Len , Potter Madeline , Rademakers Rosa , Ramos Eliana Marisa , Rankin Katherine , Rascovsky Katya , Sengdy Pheth , Shaw Leslie , Tatton Nadine , Taylor Joanne , Toga Arthur , Trojanowski John , Weintraub Sandra , Wong Bonnie , Wszolek Zbigniew , Boeve Bradley F. , Boxer Adam , Rosen Howard ,   the LEFFTDS Consortium
Published: July 2020

Objective

The Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects evaluates familial frontotemporal lobar degeneration (FTLD) kindreds with MAPT, GRN, or C9orf72 mutations. Objectives were to examine whether health‐related quality of life (HRQoL) correlates with clinical symptoms and caregiver burden, and whether self‐rated and informant‐rated HRQoL would correlate with each other.

Methods

Individuals were classified using the Clinical Dementia Rating (CDR®) Scale plus National Alzheimer's Coordinating Center (NACC) FTLD. HRQoL was measured with DEMQOL and DEMQOL‐proxy; caregiver burden with the Zarit Burden Interview (ZBI). For analysis, Pearson correlations and weighted kappa statistics were calculated.

Results

The cohort of 312 individuals included symptomatic and asymptomatic individuals. CDR® plus NACC FTLD was negatively correlated with DEMQOL (r = −0.20, P = .001), as were ZBI and DEMQOL (r = −0.22, P = .0009). There was fair agreement between subject and informant DEMQOL (κ = 0.36, P <.0001).

Conclusion

Lower HRQoL was associated with higher cognitive/behavior impairment and higher caregiver burden. These findings demonstrate the negative impact of FTLD on individuals and caregivers.
Margarine‐Like Emulsions Prepared with Coconut and Palm Oils: Analysis of Microstructure and Freeze–Thaw Stability by Differential Scanning Calorimetry
Authors: Bertoia Luz , Wagner Jorge R. , Márquez Andrés L.
Published: July 2020

The objective was to study the microstructure and freeze–thaw stability of margarine‐like emulsions formulated with vegetable fats using differential scanning calorimetry. Emulsions were prepared with 20% w/w dispersed aqueous phase and a continuous lipid phase composed by coconut oil (CO) and/or palm oil (PO) plus polyglycerol polyricinoleate (PGPR) as emulsifier. Mean temperature (TM) and crystallization enthalpy (ΔHc) were obtained from the exothermic peaks corresponding to freezing of aqueous phase. Successive cooling–heating–cooling cycles were applied to analyze changes in the exothermic peak. The emulsion prepared with CO (without PO) and 1% w/w PGPR in lipid phase showed higher water droplets size (TM = −44.8 ± 0.1 °C) and lower quantity of stabilized aqueous phase (ΔHc = 28.9 ± 1.2 J g−1) prior to application of temperature cycles, while coalescence and (presumably) water transfer processes occurred during the treatment. The use of 2% w/w PGPR was sufficient to accomplish full stabilization of aqueous phase (TM = −45.9 ± 0.1 °C; ΔHc = 42.6 ± 0.3 J g−1) before and after the freeze–thaw treatment. The total or partial (50%) substitution of CO by PO in emulsions with 1% w/w PGPR also improved the stability of the system, exhibiting slight microstructural changes. This enhanced stability would be linked to reduced water droplets size because of more rapid crystallization of lipid phase and immobilization of aqueous phase after emulsion preparation. In conclusion, it is possible to obtain margarine‐like emulsions prepared with CO and/or PO using relatively low emulsifier concentration and maintaining a desired microstructure after freeze‐thawing if the percentage ratio of both fats is controlled.
Anatomy as a Model Environment for Acquiring Professional Competencies in Medicine: Experiences at Harvard Medical School
Authors: McDaniel Katherine G. , Brown Taylor , Radford Caitlin C. , McDermott Cynthia H. , van Houten Trudy , Katz Martha E. , Stearns Dana A. , Hildebrandt Sabine
Published: July 2020

Anatomy education provides students with opportunities to learn structure and function of the human body, to acquire professional competencies such as teamwork, interpersonal skills, self‐awareness, and to reflect on and practice medical ethics. The fulfillment of this wide potential can present challenges in courses that are part of an integrated curriculum and shorter than traditional courses. This new reality, together with students' increasing concern about the stresses within medical education, led to efforts at Harvard Medical School to implement practical steps toward an optimal learning environment in anatomy. These were based on core elements of ethical anatomy education and principles of trauma‐informed care. Anatomy is conceptualized here as the “first clinical discipline,” with relational interactions between anatomical educators, medical students, and body donors/patients. Essential prerequisites for the implementation of this work were support by the medical school leadership, open partnership between engaged students and faculty, faculty coordination, and peer‐teaching. Specific interventions included pre‐course faculty development on course philosophy and invitations to students to share their thoughts on anatomy. Student responses were integrated in course introductions, combined with a pre‐dissection laboratory visit, an introductory guide, and a module on the history and ethics of anatomy. During the course, team‐building activities were scheduled, and self‐reflection encouraged, for example, through written exercises, and elective life‐body drawing. Students' responses to the interventions were overall positive, but need further evaluation. This first attempt of a systematic implementation of an optimal learning environment in anatomy led to the identification of areas in need of adjustment.
Linker‐free Gold Nanoparticle Superstructure Coated with Poly(dopamine) by Site‐Specific Polymerization for Amplifying Photothermal Cancer Therapy
Authors: Pan Liang‐Liang , Yang Yue , Li De‐Lin , Geng Wen‐Chao , Jiang Ze‐Li , Song Guo‐Sheng , Li Yong‐Jun
Published: July 2020

Although linker‐free Au nanoparticle superstructures (AuNPSTs) have demonstrated to have satisfactory photothermal conversion efficiency owing to their enhanced visible‐near‐infrared absorption caused by the interparticle coupling, they cannot be used directly for in vivo photothermal therapy (PTT) of cancer because of poor stability. To address this issue, we herein propose a polymer‐coating strategy, dressing AuNPST on a poly(dopamine) (PDA) coat, and successfully investigate the in vivo PTT effect of AuNPSTs. By employing Triton X‐100 as an emulsifier for the formation of AuNPSTs, dopamine was site‐specifically polymerized around each AuNPST by the interaction between −OH of Triton X‐100 and −NH2 of dopamine. As‐fabricated AuNPST/PDA has a sphere‐like shape with an average diameter of ∼106 nm and the PDA shell is about 10 nm PDA thick. The AuNPST/PDA shows enhanced durability to heat, acid, and alkali compared with bare AuNPST. Also, under 808 nm laser irradiation, AuNPST/PDA shows photothermal conversion efficiency of ∼33%, higher than bare AuNPST (∼23%). Significantly, AuNPST/PDA can be used as in‐vitro and in‐vivo PTT agent and shows excellent therapeutic efficacy for tumor ablation thanks to its enhanced stability and biocompatibility, indicative of its potential practicability in clinical PTT.
Recent Development in Ligation Methods for Glycopeptide and Glycoprotein Synthesis
Authors: Lin Junjie Desmond , Liu Xue‐Wei
Published: July 2020

Glycoproteins are produced by the post‐translational modification process of proteins and they play an important role in mediating various biological processes. Our understanding towards biochemical functions of individual glycoproteins has been seriously hampered due to the heterogeneous expression of carbohydrate parts in glycoproteins. Despite the advancement in recombinant expression and chromatographic techniques, the isolation of pure glycoforms remains nearly impossible. To obtain homogenous glycoproteins, tremendous efforts hves been spent in developing various ligation and glycosylation techniques. This minireview discusses selected methods for the preparation and ligation of glycopeptides. The importance of the development of new chemical synthesis method for glycoproteins has also been discussed, which would be one of the next directions in this field.
Octanuclear Ni4Ln4 Coordination Aggregates from Schiff Base Anion Supports and Connecting of Two Ni2Ln2 Cubes: Syntheses, Structures, and Magnetic Properties
Authors: Biswas Mousumi , Sañudo E. Carolina , Ray Debashis
Published: July 2020

A family of 3d–4f aggregates have been reported through guiding the dual coordination modes of ligand anion (HL−) and in situ generated ancillary bridge driven self‐assembly coordination responses toward two different types of metal ions. Reactions of lanthanide(III) nitrate (Ln=Gd, Tb, Dy, Ho and Yb), nickel(II) acetate and phenol‐based ditopic ligand anion of 2‐[{(2‐hydroxypropyl)imino}methyl]‐6‐methoxyphenol (H2L) in MeCN‐MeOH (3 : 1) mixture and LiOH provided five new octanuclear Ni‐4f coordination aggregates from two Ni2Ln2 cubanes. Single‐crystal X‐ray diffraction analysis reveals that all the members of the family are isostructural, with the central core formed from the coupling of two distorted [Ni2Ln2O4] heterometallic cubanes [Ni2Ln2(HL)2(μ3‐OH)2(OH)(OAc)4]+ (Ln=Gd (1), Tb (2), Dy (3), Ho (4) and Yb (5)). Higher coordination demand of 4f ions induced the coupling of the two cubes by (OH)(OAc)2 bridges. Variable temperature magnetic study reveals weak coupling between the Ni2+ and Ln3+ ions. For the Tb (2) and Dy (3) analogs, the compounds are SMMs without an applied dc field, whereas the Gd (1) analogue is not an SMM. The observation revealed thus that the anisotropy of the Ln3+ ions is central to display the SMM behavior within this structurally intriguing family of compounds.
Vibration‐based motion generation without any sensor or microprocessor
Authors: Masuda Yoichi , Minami Yuki , Ishikawa Masato
Published: July 2020

This article describes a decentralized controller that generates periodic motion patterns of general mechanical systems with multiple actuators, and its extremely simple implementation. The controller synchronizes the coupled dynamics of an uncertain body, the environment, and the actuators to its natural vibration modes autonomously. The major contribution of this method is that it makes possible decentralized and adaptive motion generation with multiple actuators without any sensor, microprocessor, or high‐torque and high‐precision motor. The proposed implementation of the decentralized controller is composed of a crank arm and low‐torque DC motor, and we focus on the intrinsic dynamics of the DC motor. When a reaction torque from the environment is applied to the motor shaft, the rotational speed of the motor will be changed passively. In our approach, we exploit these dynamics as a feedback controller that adjusts the phase of the DC motor. Experiments and simulations validate the fundamental features of the proposed method with a spring‐mass system, and the effects of the initial phase difference and improvement of the convergence property are reported. Moreover, an application example with a nonlinear legged robot simulation is demonstrated.
Repetitive δ‐integration of a cellulase‐encoding gene into the chromosome of an industrial Angel Yeast‐derived strain by URA3 recycling
Authors: Zou Shaolan , Sun Sifan , Zhang Xiaomao , Li Jiaman , Guo Jinghan , Hong Jiefang , Ma Yuanyuan , Zhang Minhua
Published: July 2020

Genetic modification of industrial yeast strains often faces more difficulties than that of laboratory strains. Thus, new approaches are still required. In this research, the Angel Yeast‐derived haploid strain Kα was genetically modified by multiple rounds of δ‐integration, which was achieved via URA3 recycling. Three δ‐integrative plasmids, pGδRU, pGδRU‐BGL, and pGδRU‐EG, were first constructed with two 167 bp δ sequences and a repeat‐URA3‐repeat fragment. Then, the δ‐integrative strains containing the bgl1 or egl2 gene were successfully obtained by one‐time transformation of the linearized pGδRU‐BGL or pGδRU‐EG fragment, respectively. Their counterparts in which the URA3 gene was looped out were also easily isolated by selection for growth on 5´‐fluoroorotic acid plates, although the ratio of colonies lacking URA3 to the total number of colonies decreased with increasing copy number of the corresponding integrated cellulase‐encoding gene. Similar results were observed during the second round of δ‐integration, in which the δ‐integration strain Kα(δ::bgl1‐repeat) obtained from the first round was transformed with a linearized pGδRU‐EG fragment. After 10 rounds of cell growth and transfer to fresh medium, the doubling times and enzyme activities of Kα(δ::bgl1‐repeat), Kα(δ::egl2‐repeat), and Kα(δ::bgl1‐repeat)(δ::egl2‐repeat) showed no significant change and were stable. Further, their maximum ethanol concentrations during simultaneous saccharification and fermentation of pretreated corncob over a 7‐day period were 46.35, 33.13, and 51.77 g/L, respectively, which were all substantially higher than the parent Kα strain. Thus, repetitive δ‐integration with URA3 recycling can be a feasible and valuable method for genetic engineering of Angel Yeast. These results also provide clues about some important issues related to δ‐integration, such as the structural stability of δ‐integrated genes and the effects of individual integration‐site locations on gene expression. Further be elucidation of these issues should help to fully realize the potential of δ‐integration‐based methods in industrial yeast breeding.
Hochhaus Omniturm – Baugrube und Gründung unter komplexen innerstädtischen Randbedingungen
Authors: Ramm Hendrik , Reul Oliver , Ruiken Axel , Kissel Wolfgang , Toker Engin
Published: July 2020

Der rd. 190 m hohe Omniturm wurde in den Jahren 2016–2019 im Zentrum des Bankenviertels in Frankfurt am Main erbaut und ist auf einer Kombinierten Pfahl‐Plattengründung (KPP) gegründet. Das Umfeld der Baumaßnahme ist geprägt durch sehr beengte Platzverhältnisse und die benachbarten Hochhäuser Commerzbank, Japan Center, Garden Tower und Deutsche Bank mit bis zu fünf Untergeschossen. Die rd. 16 m tiefe Baugrube wurde mithilfe einer Teildeckelbaulösung hergestellt, bei der die späteren Untergeschossdecken die horizontale Stützung des Verbaus übernahmen. Zur Gewährleistung der Sicherheit gegen Aufschwimmen der Baugrube wurde eine innen liegende Wasserhaltung zur Entspannung der wasserführenden Kalkstein‐ und Sandlagen betrieben. Mit dem Beitrag werden die wesentlichen Aspekte des Baugrubenverbaus und des Aussteifungssystems, der Wasserhaltungsmaßnahmen sowie der KPP dargestellt.
Mapping continuity and change in the intellectual structure of the knowledge base on problem‐based learning, 1974–2019: A systematic review
Authors: Hallinger Philip
Published: July 2020

Problem‐based learning (PBL) emerged during the 1970s in response to demands for active learning methods capable of developing transferable knowledge and skills in the training of doctors. Over succeeding decades, PBL was gradually adopted in other fields of education. This systematic review aimed to identify key streams of theory and empirical research that have emerged over time in PBL research and practice. The review sourced 12,036 Scopus‐indexed documents published between 1974 and 2019. Science mapping was used to reveal the ‘intellectual structure’ or key research themes that have evolved in this literature over the past 45 years. The science mapping tool used in this review was author co‐citation analysis conducted in VOSviewer software. Author co‐citation analysis identified three schools of thought that together describe the intellectual structure of the PBL knowledge base: Design of PBL Curriculum and Instruction; PBL Effectiveness; Theory and Practice in Active Learning. In addition to portraying the intellectual structure of the literature as a whole, the review also conducted longitudinal analyses aimed at highlighting structural changes in this field over time. These analyses found that although the size and impact of schools of thought associated with Design of PBL Curriculum and Instruction and PBL Effectiveness increased over time, they remained stable in terms of theoretical foci. However, the Active Learning school evolved from a small school of authors associated with Cognitive Learning Theories prior to 2000 into the largest school of thought during the most recent decades. These findings both reaffirm the theoretical underpinnings of the PBL knowledge base and highlight its increasing integration with other forms of active learning.
Bacteriophage‐receptor binding proteins for multiplex detection of Staphylococcus and Enterococcus in blood
Authors: Santos Sílvio B. , Cunha Alexandra P. , Macedo Mariana , Nogueira Catarina L. , Brandão Ana , Costa Susana P. , Melo Luís D. R. , Azeredo Joana , Carvalho Carla M.
Published: July 2020

Healthcare‐associated infections (HCAIs) affect hundreds of millions of patients, representing a significant burden for public health. They are usually associated to multidrug resistant bacteria, which increases their incidence and severity. Bloodstream infections are among the most frequent and life‐threatening HCAIs, with Enterococcus and Staphylococcus among the most common isolated pathogens. The correct and fast identification of the etiological agents is crucial for clinical decision‐making, allowing to rapidly select the appropriate antimicrobial and to prevent from overuse and misuse of antibiotics and the consequent increase in antimicrobial resistance. Conventional culture methods are still the gold standard to identify these pathogens, however, are time‐consuming and may lead to erroneous diagnosis, which compromises an efficient treatment. (Bacterio)phage receptor binding proteins (RBPs) are the structures responsible for the high specificity conferred to phages against bacteria and thus are very attractive biorecognition elements with high potential for specific detection and identification of pathogens. Taking into account all these facts, we have designed and developed a new, fast, accurate, reliable and unskilled diagnostic method based on newly identified phage RBPs and spectrofluorometric techniques that allows the multiplex detection of Enterococcus and Staphylococcus in blood samples in less than 1.5 hr after an enrichment step.
Mining, the environment, and human rights in Ghana: An area of limited statehood perspective
Authors: Idemudia Uwafiokun , Kwakyewah Cynthia , Muthuri Judy
Published: July 2020

Although the global norms meant to guide corporate environmental human rights conducts have steadily improved, there have been limited efforts directed at exploring whether business‐related environmental human rights infringements have as a result reduced. To address this gap, this paper examines the extent to which mining companies meet their responsibility to respect human rights and ensure that environmental rights of community members in mining areas are not violated. By privileging community voices, the paper offers nuanced insight into why gaps continue to persist between corporate commitment to human rights objectives and community experience in areas of limited statehood (ALS). We show that weak governmental capacity, neoliberal business model, and differences in sociocultural logics mediate between corporate environmental human rights commitments and their conduct on the ground. The paper concludes by considering the theoretical implications for business and human rights in ALS.
A Study Space Analysis for Multiple Interviewing of Child Witnesses
Authors: Waterhouse Genevieve F. , Ridley Anne M. , Bull Ray , Wilcock Rachel
Published: July 2020

This article presents a study space analysis of 44 published research studies examining the use of multiple interviews with child victims/witnesses. Study space analysis is a method of detecting gaps in the existing literature and thus determining whether ecologically valid situations that arise in practice have actually been addressed and studied. The use of this methodology is particularly useful for techniques which are being considered for changes in policy or practice, ensuring that the literature is sufficient to warrant change. Multiple or repeated interviewing has been argued by some authors to be ready for change. However, in the present study space analysis, it is concluded that despite a growing literature, there are still some key variables which require research examination prior to policy change. In particular, research is needed involving samples of children between 11 and 18 years old, participants with multiple needs and interviews regarding repeated events. Findings from the online supplementary material also identify the need for studies with longer delays between the event and the initial interview, more than two interviews of a child, phased multiple interviews and interviews conducted by professional interviewers.

‘This article presents a study space analysis of 44 published research studies examining the use of multiple interviews with child victims/witnesses’

Key Practitioner Messages

Some researchers suggest that interviewing a child more than once about an event can be beneficial for police investigations as it leads to additional accurate details.

This study concludes that there are key variables yet to be studied under controlled conditions and thus more research is required before comprehensive policy change is recommended.

Future research is required with adolescent participants, children with multiple needs and interviews about repeated events.
Cyclotide Structures Revealed by NMR, with a Little Help from X‐ray Crystallography
Authors: Handley Thomas N. G. , Wang Conan K. , Harvey Peta J. , Lawrence Nicole , Craik David J.
Published: July 2020

This review highlights the predominant role that NMR has had in determining the structures of cyclotides, a fascinating class of macrocyclic peptides found in plants. Cyclotides contain a cystine knot, a compact structural motif that is constrained by three disulfide bonds and able to resist chemical and biological degradation. Their resistance to proteolytic degradation has made cyclotides appealing as drug leads. Herein, we examine the developments that led to the identification and conclusive determination of the disulfide connectivity of cyclotides and describe in detail the structural features of exemplar cyclotides. We also review the role that X‐ray crystallography has played in resolving cyclotide structures and describe how racemic crystallography opened up the possibility of obtaining previously inaccessible X‐ray structures of cyclotides.
Optical coherence tomography predictors of target vessel myocardial infarction after provisional stenting in patients with coronary bifurcation disease
Authors: Li Xiaobo , Kan Jing , She Liping , Shrestha Rajiv , Pan Tao , You Wei , Wu Zhiming , Ge Zhen , Zhang Jun‐Jie , Gogas Bill D. , Ye Fei , Chen Shao‐Liang
Published: July 2020

Background

Provisional side branch (SB) stenting is correlated with target vessel myocardial infarction (TVMI) in patients with coronary bifurcation lesions. However, the mechanisms underlying this association remain unknown.

Objectives

To determine the correlation between SB lesion length with vulnerable plaques and TVMI using optical coherence tomography (OCT).

Background

The correlation between SB lesion length with vulnerable plaques and TVMI is unknown.

Methods

A total of 405 patients with 405 bifurcation lesions who underwent preprocedure OCT imaging of both the main vessel (MV) and the SB were enrolled. Patients were divided into long SB lesion (SB lesion length ≥10 mm) and short SB lesion (SB lesion length <10 mm) groups according to quantitative coronary analysis; they were also stratified by the presence of vulnerable plaques identified by OCT. The primary endpoint was the occurrence of TVMI after provisional stenting at 1‐year follow‐up.

Results

In total, 178 (43.9%) patients had long SB lesions. Vulnerable plaques were predominantly localized in the MV and were more frequently in the long SB lesion group (42.7%) than in the short SB lesion group (24.2%, p < .001). At 1‐year follow‐up after provisional stenting, there were 31 (7.7%) TVMIs, with 21 (11.8%) in the long SB lesion group and 10 (4.4%) in the short SB lesion group (p = .009). Multivariate regression analysis showed that long SB lesion length (p = .011), absence of vulnerable plaques in the polygon of confluence (p = .001), and true coronary bifurcation lesions (p = .004) were the three independent factors of TVMI.

Conclusions

The presence of long SB lesion with MV vulnerable plaques predicts the increased risk of TVMI after provisional stenting in patients with true coronary bifurcation lesions. Further studies are warranted to identify the best stenting techniques for coronary bifurcation lesions with long SB lesions.
Encapsulated fat necrosis mimicking abdominal liposarcoma: A case report and literature review
Authors: Watanabe Jun , Osaki Tomohiro , Tatebe Shigeru , Goto Keisuke , Endo Kanenori , Nakamura Seiichi , Hirooka Yasuaki
Published: July 2020

We report a case of an encapsulated fat necrosis without significant medical history. To differentiate from liposarcoma, it should be recognized that a half of abdominal encapsulated fat necrosis cases have a history of inflammation and surgery.
Discerning Activity and Inactivity in Earth‐Abundant Molecular Oxygen Evolution Catalysts
Authors: Craig Michael John , García‐Melchor Max
Published: July 2020

Most computational studies on the oxygen evolution reaction (OER) focus on systems which are known to catalyze this process experimentally. This work computationally examines a number of earth‐abundant metal (M=Mn, Fe, Co, Ni) complexes with tetradentate coordinating anionic ligands which, subject to the same experimental conditions, either evolve or do not evolve oxygen. We offer an account for the inactivity of catalysts and develop an effective thermodynamic descriptor to describe the activity of those catalysts that do evolve oxygen. Additionally, we describe how the functionalization of certain Fe OER catalysts can boost activity. Finally, to allow for the rapid evaluation of homogeneous OER catalysts within this family of complexes, high‐level heuristics to computationally screen these catalysts are detailed.
New Antivirals and Antibacterials Based on Silver Nanoparticles
Authors: Ciriminna Rosaria , Albo Yael , Pagliaro Mario
Published: July 2020

The rediscovery of the medical uses of silver provides another noticeable example, this time at the interface of chemistry and medicine, of the real (and nonlinear) progress of scientific research. Several new silver‐based antimicrobial products have thus been commercialized in the last two decades. Next‐generation antibacterials and antivirals of broad scope, low toxicity and affordable cost, we argue in this study, will be based on microencapsulated Ag nanoparticles.
Optimal Geometric Parameters for 3D Electrodes in Bioelectrochemical Systems: A Systematic Approach
Authors: Moß Christopher , Jarmatz Niklas , Heinze Janina , Scholl Stephan , Schröder Uwe
Published: July 2020

In this study, the performance of electroactive bacteria (EAB), cultivated inside tubular electrode ducts, is systematically investigated to derive predictions on the behavior of EAB under conditions limited by electrochemical losses. A modeling approach is applied to assess the influence of the electrochemical losses on the electrochemical performance and scaling characteristics of complex 3D structures, such as sponges and foams. A modular flow reactor is designed that provides laminar and reproducible flow conditions as a platform for the systematic electrochemical and bioelectrochemical characterization of 3D electrodes in bioelectrochemical systems (BES). The bioelectrochemical experiments are carried out in a set of reactors incorporating cylindrical electrodes exhibiting ducts of 1 cm length and different diameters ranging from 0.1 cm up to 1 cm. Single duct calculations are extrapolated to three dimensions through geometrical considerations; trends in 3D bioanode performance are demonstrated using the resulting simplified 3D structure. The combined experimental and modeling approach constitutes a framework for future studies on systematic electrode design.
Coupled Electrochemical and Microbial Catalysis for the Production of Polymer Bricks
Authors: Hegner Richard , Neubert Katharina , Kroner Cora , Holtmann Dirk , Harnisch Falk
Published: July 2020

Power‐to‐X technologies have the potential to pave the way towards a future resource‐secure bioeconomy as they enable the exploitation of renewable resources and CO2. Herein, the coupled electrocatalytic and microbial catalysis of the C5‐polymer precursors mesaconate and 2S‐methylsuccinate from CO2 and electric energy by in situ coupling electrochemical and microbial catalysis at 1 L‐scale was developed. In the first phase, 6.1±2.5 mm formate was produced by electrochemical CO2 reduction. In the second phase, formate served as the substrate for microbial catalysis by an engineered strain of Methylobacterium extorquens AM‐1 producing 7±2 μm and 10±5 μm of mesaconate and 2S‐methylsuccinate, respectively. The proof of concept showed an overall conversion efficiency of 0.2 % being 0.4 % of the theoretical maximum.
A pH‐Neutral, Aqueous Redox Flow Battery with a 3600‐Cycle Lifetime: Micellization‐Enabled High Stability and Crossover Suppression
Authors: Chai Jingchao , Wang Xiao , Lashgari Amir , Williams Caroline K. , Jiang Jianbing (Jimmy)
Published: July 2020

Redox‐flow batteries (RFBs) are a highly promising large‐scale energy storage technology for mitigating the intermittent nature of renewable energy sources. Here, the design and implementation of a micellization strategy in an anthraquinone‐based, pH‐neutral, nontoxic, and metal‐free aqueous RFB is reported. The micellization strategy (1) improves stability by protecting the redox‐active anthraquinone core with a hydrophilic poly(ethylene glycol) shell and (2) increases the overall size to mitigate the crossover issue through a physical blocking mechanism. Paired with a well‐established potassium ferrocyanide catholyte, the micelle‐based RFB displayed an excellent capacity retention of 90.7 % after 3600 charge/discharge cycles (28.3 days), corresponding to a capacity retention of 99.67 % per day and 99.998 % per cycle. The mechanistic studies of redox‐active materials were also conducted and indicated the absence of side reactions commonly observed in other anthraquinone‐based RFBs. The outstanding performance of the RFB demonstrates the effectiveness of the micellization strategy for enhancing the performance of organic material‐based aqueous RFBs.
Analysis of single‐cell RNAseq identifies transitional states of T cells associated with hepatocellular carcinoma
Authors: Yang Yanying , Liu Fangming , Liu Weiren , Ma Mingyue , Gao Jie , Lu Yan , Huang Li‐Hao , Li Xiaoying , Shi Yinghong , Wang Xiangdong , Wu Duojiao
Published: July 2020

Background

Exhausted T cells and regulatory T cells (Tregs) comprise diverse subsets of tumor immunosuppressive microenvironment that play key roles in tumor progress. Understanding subset diversity in T cells is a critical question for developing cancer immunotherapy.

Methods

A total of 235 specimens from surgical resections of hepatocellular carcinoma (HCC) patients were examined for infiltration of exhausted T cell (Tex) in tumor and adjacent tissue. We conducted deep single‐cell targeted immune profiling on CD3+ cells collected from tumor tissues, adjacent normal tissues (ANTs) and peripheral blood of HCC patients. Total 10 cell clusters were identified with distinct distributions and characteristics.

Results

We observed transitional differentiation of exhausted CD8+T cells and Tregs increasingly enriched in tumor tissue. The accumulation and location of Tex were related to the differences in the long‐term clinical outcome of HCC. Furthermore, data of single‐cell RNA‐seq showed that (1) cells transforming from effector CD8+ T cells to exhausted CD8+ T cells simultaneously expressed upregulated effector molecules and inhibitory receptors, (2) indicated alteration of gene expression related to stress response and cell cycle at early exhaustion stage, and (3) immunosuppressive Treg had profound activation in comparison to resting Tregs.

Conclusions

T cell exhaustion is a progressive process, and the gene‐expression profiling displayed T cell exhaustion and anergy are different. Accordingly, it is possible that functional exhaustion is caused by the combination effects of passive defects and overactivation in stress response. The results help to understand the dynamic framework of T cells function in cancer which is important for designing rational cancer immunotherapies.
Molten Salt Synthesis of Atomic Heterogeneous Catalysts: Old Chemistry for Advanced Materials
Authors: Xiao Mu , Luo Bin , Konarova Muxina , Wang Zhiliang , Wang Lianzhou
Published: July 2020

Atomic catalysts have demonstrated great potential for the rational design of new heterogeneous catalysts with excellent activity, stability, and selectivity for various industrial reactions. However, knowing how to synthesize atomic catalysts in a low‐cost, high‐yield, and environment‐friendly manner remains highly challenging. Molten‐salt‐assisted material synthesis as an old chemical preparation technology that has recently been deliberately modified to meet the requirements of atomic catalyst design. Here we provide a critical review of the recent progress of the molten‐salt‐assisted synthesis of atomic catalysts. The property and working mechanisms of the molten‐salt‐assisted method are firstly introduced, followed by some typical examples to demonstrate the precise atomic catalyst control. In the end, perspectives in this field are briefly discussed. This review is expected to raise attention for applying classic molten salt synthesis in the design of new generations of advanced materials.
Synthetic and Structural Studies on a New Type of [Fe]‐Hydrogenase Mimics Each Containing One Hantzsch Ester Moiety
Authors: Song Li‐Cheng , Liu Bei‐Bei , Xu Kai‐Kai
Published: July 2020

To develop the synthetic methodology for [Fe]‐H2ase models, a new type of the Hantzsch ester moiety‐containing [Fe]‐H2ase models (1–7) has been synthesized on the basis of preparing a series of new 2,6‐disubstituted pyridine precursors (L1–L10). Thus, the iodo models [2‐COCH2‐6‐(HEH)C5H3N]Fe(CO)2I (1), {2‐COCH2‐6‐[C6H4(HEH)]C5H3N}Fe(CO)2I (2), and {2‐COCH2‐6‐[Me(HEH)]C5H3N}Fe(CO)2I (3) could be prepared by reactions of precursors 2‐TsOCH2‐6‐(HEH)C5H3N (L2), 2‐TsOCH2‐6‐[C6H4(HEH)]C5H3N (L6), and 2‐TsOCH2‐6‐[Me(HEH)]C5H3N (L10) with Na2Fe(CO)4 followed by treatment of the resulting Fe(0) intermediates M1, M2 and M3 with iodine, respectively. In addition, further treatment of model 1 with AgOTf followed by reaction of the resulting Fe(II) intermediate M4 with MeCN gave the MeCN‐coordinated model {[2‐COCH2‐6‐(HEH)C5H3N]Fe(CO)2(MeCN)}(OTf) (4), whereas reaction of precursor L2 with Na2Fe(CO)4 followed by treatment of intermediate M1 with dimers (RCO2)2 afforded benzoato models [2‐COCH2‐6‐(HEH)C5H3N]Fe(CO)2(O2CR) (5, R = 4‐ClC6H4; 6, 2,6‐F2C6H3; 7, 2‐F3CC6H4). All the new precursors L1–L10 and models 1–7 were characterized by various spectroscopic methods and for some of them by X‐ray crystallography.
Experimental study of flame spread over PE‐insulated single copper core wire under varying pressure and electric current
Authors: Wang Zhi , Zhou Tiannian , Wei Ruichao , Wang Jian
Published: July 2020

In this study, the flame spread over a thin wire with overload current (0‐16 A) has been experimentally investigated at both normal pressure (Hefei: altitude 50 m, 100 kPa) and reduced pressure (Lijiang: altitude 2400 m, 76 kPa; Lhasa: altitude 3650 m, 64 kPa). Polyethylene‐insulated single‐core wires, comprising Cu as the inner core of diameter 0.30, 0.50, and 0.80 mm and insulation thickness 0.15 and 0.30 mm, are used as samples. The experimental results clearly indicate that the height of the flame increases with the electric current and ambient pressure, but the flame width changes only slightly. At identical conditions, the finer the wire, the faster the flame spreads. The flame spread rate increases with the electric current and ambient pressure. A simplified thermal balance analysis concerning the load current is developed to calculate the flame spread rate, and the calculated flame spread rates are shown to be fairly consistent with the experimental values at different electric currents for different wires at both ambient pressures. In addition, the coupled effect of electric current and ambient pressure on the flame spread is discussed. These results may be meaningful for promoting the research process of wire fire safety.
Fully automatic brain tumor extraction and tissue segmentation from multimodal MRI brain images
Authors: Thiruvenkadam Kalaiselvi , Nagarajan Kalaichelvi
Published: July 2020

Segmentation of Brain tumor from the magnetic resonance imaging (MRI) of head scans is an essential requirement for clinical diagnosis since manual segmentation is a fatigue and time‐consuming process. Recent computer‐aided diagnosis systems depend on the development of fully automatic methods to overcome these problems. In the present work, a fully automated algorithm is proposed to extract and segment tumor regions from multimodal magnetic resonance imaging (MMMRI) sequences. The algorithm has three phases: (a) tumor portion extraction, (b) tumor substructure segmentation, and (c) 3D postprocessing. First, the algorithm extracts tumor portion using a set of image processing operations from T2, fluid‐attenuated inversion recovery (FLAIR), and T1C images. Here, the proposed modified fuzzy c means clustering algorithm is used for enhancing the tumor portion extraction process. Then, the substructures of tumor such as edema, enhancing tumor, and necrotic regions are segmented from MMMRI sequences, T2, FLAIR, and T1C using region‐wise set operations in Phase II. Finally, 3D visualization of the segmented tumor and volume estimation is performed as postprocessing in Phase III. The proposed work was experimented on BraTS 2013 dataset. The quantitative analysis is performed using William's Index, Dice, sensitivity, specificity, and accuracy and is compared with 19 state‐of‐the‐art methods. The proposed method yields comparable results as 77%, 53%, and 59% of Dice for complete, core, and enhancing tumor regions, respectively.
Molecular identification of Candida isolates by Real‐time PCR‐high‐resolution melting analysis and investigation of the genetic diversity of Candida species
Authors: Eghtedar Nejad Esmaeel , Ghasemi Nejad Almani Pooya , Mohammadi Mohammad Ali , Salari Samira
Published: July 2020

Background

Candida species are considered as the cause of one of the most important opportunistic fungal diseases. Accurate identification of Candida species is important because of antifungal susceptibility patterns are different among these species, so proper identification helps in the selection of antifungal drugs for the prevention and treatment. Phenotypic methods for identification of Candida species, which are widely used in clinical microbiology laboratories, have some limitations. Real‐time PCR followed by the high‐resolution melting analysis (HRMA) is a novel approach for the rapid recognition of pathogenic fungi. Molecular phylogeny is essential for obtaining a better understanding of the evolution of the genus Candida and the identification of the relative degree of the Candida species. The purpose of this study was molecular identification of Candida isolates by Real‐time PCR‐high‐resolution melting analysis and investigation of the genetic diversity of Candida species.

Methods

Two hundred and thirty‐two Candida isolates including 111 Candida isolates obtained from 96 HIV/AIDS patients and 121 Candida isolates obtained from 98 non‐HIV persons were identified by real‐time PCR and high‐resolution melting curve analysis. To evaluate genetic diversity and relationships among Candida species, PCR products of nine clinical Candida isolates, as a representative of each kind of species, were randomly selected for DNA sequence analysis.

Results

In HIV/AIDS patients, six species of Candida spp. were identified as follows: C albicans (n = 64; 57.7%), C glabrata (n = 31; 27.92%), C parapsilosis (n = 9; 8.1%), C tropicalis (n = 4; 3.6%), C krusei (n = 2; 1.8%), and C kefyr (n = 1; 0.90%). In non‐HIV persons, we identified eight species of Candida including C albicans (n = 46; 38.33%) followed by C glabrata and C krusei (each one, n = 18; 15%), C tropicalis (n = 13; 10.83%), C lusitaniae (n = 12; 5.17%), C parapsilosis (n = 10; 4.31%), and C kefyr and C guillermondii (each one, n = 2; 1.66%). Also, the phylogenetic analysis showed the presence of two main clades and six separate subclades. Accordingly, about 88.9% of the isolates were located in clade I and 11.10% of the studied isolates were in clade II.

Conclusions

Real‐time PCR followed by high‐resolution melting analysis (HRMA) is known as a reliable, fast, and simple approach for detection and accurate identification of Candida species, especially in clinical samples.