bluuebunny/crossref_metadata_2025 huggingface dataset:
Libertad de expresión y censura: la violencia estructural y sus efectos en la cultura española
Authors: Oliveira Julieti Sussi , González-Fernádez Sara
Published: February 2019

La libertad de expresión, como pilar de un Estado democrático, garantiza que la sociedad pueda sentirse libre tanto para informarse como para expresarse y se convierte, por tanto, en un derecho incuestionable. En los últimos años, la libertad de expresión en España está viviendo un retroceso a partir de las reformas legislativas que han tenido lugar desde 2013, afectando directamente a las manifestaciones culturales con unas medidas legislativas, en ocasiones, imprecisas que hacen resurgir coacciones y limitaciones impropias de un Estado democrático.
Censura e pós-censura: uma síntese sobre as formas clássicas e atuais de controle da produção artística nacional
Authors: Castilho Costa Maria Cristina , Sousa Junior Walter de
Published: February 2019

Presentes na formação histórica, política e cultural do país, os mecanismos censórios estiveram sempre alertas à produção artística nacional nos últimos 500 anos, como forma de exercer o poder político, enquanto estatal, e disseminada na sociedade como no período atual, chamada de pós-censura. Este artigo tem por finalidade refletir sobre esses processos a partir das pesquisas que o Observatório de Comunicação, Liberdade de Expressão e Censura (OBCOM), da Escola de Comunicações e Artes da USP vem realizando nos últimos 18 anos.
Mediar a censura: entrevistas com educadoras/es de exposições que sofreram ataques
Authors: Honorato Cayo , Kunsch Graziela
Published: February 2019

Considerando que parte significativa das controvérsias culturais, a partir do caso Queermuseu, constitui o próprio material ao qual o trabalho de mediação se dedica – muito embora as mediadoras e educadoras tenham sido muito pouco consultadas publicamente a respeito dessas questões –, julgamos oportuno entrevistar educadoras e educadores de diferentes instituições e exposições envolvidas (Santander Cultural, MAM-SP, MASP e Trienal de Artes do Sesc) sobre sua atuações e eventuais experiências de transformação nesse processo.
Patient‐Reported Outcomes One to Five Years After Anterior Cruciate Ligament Reconstruction: The Effect of Combined Injury and Associations With Osteoarthritis Features Defined on Magnetic Resonance Imaging
Authors: Patterson Brooke E. , Culvenor Adam G. , Barton Christian J. , Guermazi Ali , Stefanik Joshua J. , Crossley Kay M.
Published: February 2019

Objective

Persistent symptoms and poor quality of life (QoL) are common following anterior cruciate ligament reconstruction (ACLR). We aimed to determine the influence of a combined ACL injury (i.e., concomitant meniscectomy and/or arthroscopic chondral defect at the time of ACLR and/or secondary injury/surgery to ACLR knee) and cartilage defects defined on magnetic resonance imaging (MRI), bone marrow lesions (BMLs), and meniscal lesions on patient‐reported outcomes 1 to 5 years after ACLR.

Methods

A total of 80 participants (50 men; mean ± SD age 32 ± 14 years) completed the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) questionnaires as well as a 3T MRI assessment at 1 and 5 years after ACLR. Median patient‐reported outcome scores were compared between isolated and combined ACL injuries and with published normative values. Using multivariate regression, we evaluated the association between compartment‐specific MRI cartilage, BMLs, and meniscal lesions and patient‐reported outcomes at 1 and 5 years.

Results

Individuals with a combined injury had significantly worse scores in the KOOS subscale of function in sport and recreation (KOOS sport/rec) and in the IKDC questionnaire at 1 year, and worse scores in the KOOS subscales of pain (KOOS pain), symptoms (KOOS symptoms), and QoL (KOOS QoL) and in the IKDC questionnaire at 5 years compared to those with an isolated injury. Although no feature on MRI was associated with patient‐reported outcomes cross‐sectionally at 1 year, patellofemoral cartilage defects at 1 year were significantly associated with worse 5‐year KOOS symptoms (β = –9.79, 95% confidence interval [95% CI] –16.67, –2.91), KOOS sport/rec (β = –7.94, 95% CI –15.27, –0.61), KOOS QoL (β = –8.29, 95% CI –15.28, –1.29), and IKDC (β = –4.79, 95% CI –9.34, –0.24) scores. Patellofemoral cartilage defects at 5 years were also significantly associated with worse 5‐year KOOS symptoms (β = –6.86, 95% CI –13.49, –0.24) and KOOS QoL (β = –11.71, 95% CI –19.08, –4.33) scores.

Conclusion

Combined injury and patellofemoral cartilage defects shown on MRI are associated with poorer long‐term outcomes. Clinicians should be vigilant and aware of individuals with these injuries, as such individuals may benefit from targeted interventions to improve QoL and optimize symptoms.
Boosting Photovoltaic Performance for Lead Halide Perovskites Solar Cells with BF4− Anion Substitutions
Authors: Zhang Jie , Wu Shengfan , Liu Tiantian , Zhu Zonglong , Jen Alex K.‐Y.
Published: February 2019

Composition engineering is a particularly simple and effective approach especially using mixed cations and halide anions to optimize the morphology, crystallinity, and light absorption of perovskite films. However, there are very few reports on the use of anion substitutions to develop uniform and highly crystalline perovskite films with large grain size and reduced defects. Here, the first report of employing tetrafluoroborate (BF4−) anion substitutions to improve the properties of (FA = formamidinium, MA = methylammonium (FAPbI3)0.83(MAPbBr3)0.17) perovskite films is demonstrated. The BF4− can be successfully incorporated into a mixed‐ion perovskite crystal frame, leading to lattice relaxation and a longer photoluminescence lifetime, higher recombination resistance, and 1–2 orders magnitude lower trap density in prepared perovskite films and derived solar cells. These advantages benefit the performance of perovskite solar cells (PVSCs), resulting in an improved power conversion efficiency (PCE) of 20.16% from 17.55% due to enhanced open‐circuit voltage (VOC) and fill factor. This is the highest PCE for BF4− anion substituted lead halide PVSCs reported to date. This work provides insight for further exploration of anion substitutions in perovskites to enhance the performance of PVSCs and other optoelectronic devices.
A Flexible Microwave Shield with Tunable Frequency‐Transmission and Electromagnetic Compatibility
Authors: Lv Hualiang , Yang Zhihong , Ong Samuel Jun Hoong , Wei Chao , Liao Hanbin , Xi Shibo , Du Yonghua , Ji Guangbin , Xu Zhichuan J.
Published: February 2019

Wireless techniques have improved life quality for many. However, the drawbacks like instable signal and high loss in air of electromagnetic interference hinder its further development. One solution is to develop a smart material or device, which can selectively receive a specific frequency (fs) of electromagnetic wave with less loss, and simultaneously show effective shielding against unwanted waves (frequency is denoted as fp). A bottleneck has been reached, such that using materials alone is unable to achieve the above due to the limitation of the intrinsic physical properties of materials. Here, a strategy combining the material structure design with a voltage control is proposed to overcome the limitation of materials toward the aforementioned task. The efforts are focused on exploring a suitable electrically tunable material with a sensitive response to an external voltage and the flexibility to be engineered to the needed macrostructure. As a result, the fs region can be fine‐tuned to 8–8.4, 8–9.3, and 8–10.3 GHz.
Detecting Li Dendrites in a Two‐Electrode Battery System
Authors: Wang Tuo , Salvatierra Rodrigo Villegas , Tour James M.
Published: February 2019

The use of high‐energy‐density Li metal anodes in rechargeable batteries is not possible because of dendrite formation that can potentially result in a battery fire. Although so‐called dendrite‐free Li metal anodes have been reported in many recent publications, Li dendrite growth is still kinetically favorable and it remains a severe safety concern in mass production. Here, a detection system capable of alerting for Li dendrite formation in a two‐electrode battery with no additional electrodes required is reported. When dendrites contact a red phosphorous‐coated separator, dendrite growth is revealed by a significant voltage change. This can activate a signal through the battery management system, warning of the presence of Li dendrites and leading to shutdown of the battery before the dendrites become dangerous.
Self‐Connected Ag Nanoporous Sponge Embedded in Sputtered Polytetrafluoroethylene for Highly Stretchable and Semi‐Transparent Electrodes
Authors: Lim Ji‐Eun , Yoon Sunyoung , Hwang Byeong‐Ung , Lee Nae‐Eung , Kim Han‐Ki
Published: February 2019

High‐performance wearable electronics require highly stretchable and conductive materials that are prepared by simple, scalable processes to be implemented in the essential roles of electrodes and interconnects. Here, room temperature fabrication of highly stretchable electrodes consisting of self‐connected Ag nanoporous sponge embedded in polytetrafluoroethylene (PTFE) matrix on stretchable polyurethane substrates using a metal‐polymer co‐sputtering process is demonstrated. The metallic Ag nanoporous sponge networks (NSNs) embedded in PTFE matrix show minimal changes to resistance even after stretching by 50% and after 10 000 cycles under 20% strain due to the well‐connected Ag NSNs and the stretchable PTFE matrix. The feasibility of this hybrid material as stretchable interconnects and electrodes for stretchable thin film heaters and strain sensors is also demonstrated. Because the Ag NSNs embedded in PTFE matrix are simply fabricated by a typical sputtering process, which is compatible with current electronics fabrication processes, it is strongly expected that the Ag‐PTFE hybrid electrodes can be easily applied as universal stretchable electrodes for wearable thin film heaters, stretchable interconnectors, and stretchable strain sensors.
Photoactive Organic Substrates for Cell Stimulation: Progress and Perspectives
Authors: Hopkins Jonathan , Travaglini Lorenzo , Lauto Antonio , Cramer Tobias , Fraboni Beatrice , Seidel Jan , Mawad Damia
Published: February 2019

Modulating the cell membrane potential provides an opportunity to control electrical signaling that is central to cellular physiology and its proper biological function. Among the many technological tools available to enable this modulation, optical stimulation through a photoactive substrate is a powerful strategy that is minimally invasive and wireless. This is critical to avoid disrupting the structural integrity of the cell membrane that is often caused by the use of electrical stimulation electrodes or changing its genetic footprints if optogenetics is the approach taken to photomodulate its electrophysiology. The use of a photoactive substrate such as an organic semiconductor combines optoelectronic properties with mechanical tissue compatibility, which is unachievable with inorganic semiconductors. This research news first discusses the mechanisms of cell photostimulation via these organic photoactive substrates and techniques employed to characterize their photoresponse. Then a summary of the relevant organic materials and their recent applications in cellular photostimulation is presented. Finally, the challenges in the field are described and a perspective on how to address these is provided.
Metal Oxide and Hydroxide–Based Aqueous Supercapacitors: From Charge Storage Mechanisms and Functional Electrode Engineering to Need‐Tailored Devices
Authors: Nguyen Tuyen , Montemor Maria de Fátima
Published: February 2019

Energy storage devices that efficiently use energy, in particular renewable energy, are being actively pursued. Aqueous redox supercapacitors, which operate in high ionic conductivity and environmentally friendly aqueous electrolytes, storing and releasing high amounts of charge with rapid response rate and long cycling life, are emerging as a solution for energy storage applications. At the core of these devices, electrode materials and their assembling into rational configurations are the main factors governing the charge storage properties of supercapacitors. Redox‐active metal compounds, particularly oxides and hydroxides that store charge via reversible valence change redox reactions with electrolyte ions, are prospective candidates to optimize the electrochemical performance of supercapacitors. To address this target, collaborative investigations, addressing different streams, from fundamental charge storage mechanisms and electrode materials engineering to need‐tailored device assemblies, are the key. Over the last few years, significant achievements in metal oxide and hydroxide–based aqueous supercapacitors have been reported. This work discusses the most recent achievements and trends in this field and brings into the spotlight the authors' viewpoints.
Low Power Parylene‐Based Memristors with a Graphene Barrier Layer for Flexible Electronics Applications
Authors: Chen Qingyu , Lin Min , Wang Zongwei , Zhao Xiaolong , Cai Yimao , Liu Qi , Fang Yichen , Yang Yuchao , He Ming , Huang Ru
Published: February 2019

Lowering the programing power consumption is of importance to capacitate high‐efficiency flexible neuromorphic electronics. However, this remains particularly challenging for organic flexible memristor due to its high reset current. Here a robust route is reported to capitalize on graphene with native nanopores as a barrier layer for the parylene‐based flexible memristors, eventually conferring the devices to be operated with ultralow reset current (<50 µA) and programming power consumption (<150 µW). The graphene‐integrated memristor device in the architecture of Al/graphene/parylene/W (G‐memristor) lowers the reset current by ≈47 times and the programming power consumption by ≈14 times, respectively, as compared with those without the graphene barrier layer. Intriguingly, the conductive atomic force microscope characterizations reveal the metallic filamentary‐type switching mechanism of these G‐memristor devices, in which the intrinsic nanopores on graphene impart the formation of finer conductive filaments between Al electrode and parylene layer while suppressing the diffusion of mass metal atoms across the architecture. The integration of nanopores graphene as the barrier layer of organic memristors offers a promising route to low‐power flexible neuromorphic computing electronics.
Efficient and Stable Chemical Passivation on Perovskite Surface via Bidentate Anchoring
Authors: Zhang Hao , Wu Yongzhen , Shen Chao , Li Erpeng , Yan Chenxu , Zhang Weiwei , Tian He , Han Liyuan , Zhu Wei‐Hong
Published: February 2019

Chemical passivation is an effective approach to suppress the grain surface dominated charge recombination in perovskite solar cells (PSCs). However, the passivation effect is usually labile on perovskite crystal surface since most passivating agents are weakly anchored. Here, the use of a bidentate molecule, 2‐mercaptopyridine (2‐MP), to increase anchoring strength for improving the passivation efficacy and stability synchronously is demonstrated. Compared to monodentate counterparts of pyridine and p‐toluenethiol, 2‐MP passivation on CH3NH3PbI3 film results in twofold improvement of photoluminescence lifetime and remarkably enhanced tolerance to chlorobenzene washing and vacuum heating, which improve the power conversion efficiency of n–i–p planar structured PSCs from 18.35% to 20.28%, with open‐circuit voltage approaching 1.18 V. Moreover, the CH3NH3PbI3 films passivated with 2‐MP exhibit unprecedented humid‐stability that they can be exposed to saturated humidity for at least 5 h, mainly due to the passivation induced surface deactivation, which renders the unencapsulated devices retaining 93% of the initial efficiency after 60 days aging in air with relative humidity of 60–70%.
Serum neurofilaments increase at progressive multifocal leukoencephalopathy onset in natalizumab‐treated multiple sclerosis patients
Authors: Dalla Costa Gloria , Martinelli Vittorio , Moiola Lucia , Sangalli Francesca , Colombo Bruno , Finardi Annamaria , Cinque Paola , Kolb Eva‐Maria , Haghikia Aiden , Gold Ralf , Furlan Roberto , Comi Giancarlo
Published: February 2019

This study analyzed serum neurofilament light chains (NfL) in 2 European cohorts of 312 multiple sclerosis (MS) patients to investigate whether NfL are biomarkers of progressive multifocal leukoencephalopathy (PML) during natalizumab treatment. The cohort comprised 25 PML, 136 natalizumab‐treated, and 151 untreated MS patients. Patients subsequently developing PML had similar NfL to other natalizumab‐treated MS patients. At PML onset, NfL were 10‐fold higher than in the pre‐PML condition and in natalizumab‐treated or untreated MS patients, and NfL continued to increase until onset of immune reconstitution inflammatory syndrome. The results suggest that in natalizumab‐treated patients, NfL may represent an early and accessible marker of PML. Ann Neurol 2019;85:606–610
Mechanism of DNA‐Induced Phase Separation for Transcriptional Repressor VRN1
Authors: Zhou Huabin , Song Zihan , Zhong Sheng , Zuo Linyu , Qi Zhi , Qu Li‐Jia , Lai Luhua
Published: February 2019

Phase separation of proteins/nucleic acids to form non‐membrane organelles is crucial in cellular gene‐expression regulation. However, little is known about transcriptional regulator phase separation and the underlying molecular mechanism. Vernalization 1 (VRN1) encodes a crucial transcriptional repressor involved in plant vernalization that contains two B3 DNA‐binding domains connected by an intrinsic disorder region (IDR) and nonspecifically binds DNA. We found that the Arabidopsis VRN1 protein undergoes liquid–liquid phase separation (LLPS) with DNA that is driven by multivalent protein–DNA interactions (LLPS), and that both B3 domains are required. The distribution of charged residues in the VRN1 IDR modulates the interaction strength between VRN1 and DNA, and changes in the charge pattern lead to interconversion between different states (precipitates, liquid droplets, and no phase separation). We further showed that VRN1 forms puncta in plant cell nuclei, suggesting that it may stabilize the vernalized state by repressing gene expression through LLPS.
Struktur einer archaealen B‐Familien‐DNA‐Polymerase in Komplex mit einem chemisch modifizierten Nukleotid
Authors: Kropp Heike M. , Diederichs Kay , Marx Andreas
Published: February 2019

Archaeale B‐Familien‐DNA‐Polymerasen (DNA‐Pols) sind die treibende Kraft führender biotechnologischer Anwendungen wie moderne Sequenzierungsansätze. Die Akzeptanz chemisch modifizierter Nukleotide durch DNA‐Pols ist der Schlüssel zu diesen Technologien. Bis jetzt sind keine strukturellen Daten für diese DNA‐Pols in Komplexen mit modifizierten Substraten verfügbar, die zum Verständnis der Interaktionen zwischen Enzym und chemischer Modifikation sowie der Entwicklung von Nukleotiden der nächsten Generation beitragen könnten. Dafür haben wir eine Exonuklease‐defiziente Variante des Wildtyps der B‐Familien KOD‐DNA‐Pol mit einem modifizierten Nukleotid in einem geschlossenen, ternären Komplex kristallisiert. Zum Vergleich haben wir die A‐Familien‐DNA‐Pol KlenTaq mit demselben Nukleotid kristallisiert. Die beiden Kristallstrukturen erklären wie die Modifikation in den A‐ und B‐Familien‐DNA‐Pols durch das Protein und die DNA in zwei unterschiedliche Konformationen gelenkt wird. Außerdem erlauben die Strukturen Rückschlüsse darauf, wie die jeweilige Konformation die Prozessierung des modifizierten Nukleotids beeinflusst. Insgesamt bietet diese Studie erste Einblicke wie B‐Familien‐DNA‐Pols mit relevantem modifiziertem Substrat interagieren.
Spiro‐Bicyclic Bisborane Catalysts for Metal‐Free Chemoselective and Enantioselective Hydrogenation of Quinolines
Authors: Li Xiang , Tian Jun‐Jie , Liu Ning , Tu Xian‐Shuang , Zeng Ning‐Ning , Wang Xiao‐Chen
Published: February 2019

A new series of spiro‐bicyclic bisborane catalysts has been prepared by means of hydroboration reactions of C2‐symmetric spiro‐bicyclic dienes with HB(C6F5)2 and HB(p‐C6F4H)2. When used for hydrogenation of quinolines, these catalysts give excellent yields and enantiomeric excesses, and show turnover numbers of up to 460. The most attractive feature of these metal‐free hydrogenation reactions was the broad functional‐group tolerance, making this method complementary to existing methods for quinoline hydrogenation.
The Use of Clinical Reasoning Skills in the Setting of Uncertainty: A Case of Trial Femoral Head Migration
Authors: Quiroga‐Garza Alejandro , Teran‐Garza Rodrigo , Elizondo‐Omaña Rodrigo Enrique , Guzmán-López Santos
Published: February 2019

Clinical skills and medical knowledge enable physicians to overcome the uncertainty of emergent and rare clinical scenarios. Recently, a growing emphasis on evidence‐based medicine (EBM) has flooded medical curricula of universities across the globe with guideline‐based material, and while it has given teachers and students new tools to improve medical education, clinical reasoning must be reaffirmed in its capacity to provide physicians with the ability to solve unexpected clinical scenarios. Anatomical education in medical school should have two main objectives: to acquire anatomical knowledge and to develop the skill of applying that knowledge in clinical scenarios. The authors present a clinical scenario in which an unexpected and rare complication occurred during a routine elective hip replacement surgery. The general surgeon presiding over the case, also an anatomy professor, solved the problem using clinical reasoning and anatomical knowledge. It was a clear example of how clinical reasoning is key in approaching unprecedented, rare, or unknown complications. The intention of this scenario is to remind colleagues and medical schools that, although EBM is the standard, educators must uphold sound clinical reasoning to best prepare health care providers for their careers.
Synthetic Approaches to Star‐Shaped Molecules with 1,3,5‐Trisubstituted Aromatic Cores
Authors: Kotha Sambasivarao , Meshram Milind , Panguluri Nageswara Rao , Shah Vrajesh R. , Todeti Saidulu , Shirbhate Mukesh E.
Published: February 2019

Herein, we summarize the synthetic approaches that have been developed for the synthesis of star‐shaped molecules. Typically, to design such highly functionalized molecules, simple building blocks are first assembled through trimerization reactions, starting from commercially available starting materials. Then, these building blocks are synthetically manipulated to generate extended star‐shaped molecules. We also discuss the syntheses of star‐shaped molecules that contain 2,4,6‐trisubstituted 1,3,5‐triazine or 1,3,5‐trisubstituted benzene rings as a central core and diverse substituted styrene, phenyl, and fluorene derivatives at their periphery, which endows these molecules with extended conjugation. A variety of metal‐catalyzed reactions, such as Suzuki, Buchwald–Hartwig, Sonogashira, Heck, and Negishi cross‐coupling reactions, as well as metathesis, have been employed to functionalize a range of star‐shaped molecules. The methods described herein will be helpful for designing a wide range of intricate compounds that are highly valuable in the fields of supramolecular chemistry and materials science. Owing to space limitations, we will not cover all of the publications on this topic. Instead, we will focus on examples that were reported by our research group and other relevant recent literature. Apart from the trimerization sequence, this Minireview has been structured based on the key reactions that were used to prepare the star‐shaped molecules and other higher analogues. Finally, some examples that do not fit into this classification are discussed.
Impact of Hydrogen Bonding on the Fluorescence of N‐Amidinated Fluoroquinolones
Authors: Xie Sheng , Manuguri Sesha , Ramström Olof , Yan Mingdi
Published: February 2019

The fluorescence properties of AIE‐active N‐amidinated fluoroquinolones, efficiently obtained by a perfluoroaryl azide–aldehyde–amine reaction, have been studied. The fluorophores were discovered to elicit a highly sensitive fluorescence quenching response towards guest molecules with hydrogen‐bond‐donating ability. This effect was evaluated in a range of protic/aprotic solvents with different H‐bonding capabilities, and also in aqueous media. The influence of acid/base was furthermore addressed. The hydrogen‐bonding interactions were studied by IR, NMR, UV/Vis and time‐resolved fluorescence decay, revealing their roles in quenching of the fluorescence emission. Due to the pronounced quenching property of water, the N‐amidinated fluoroquinolones could be utilized as fluorescent probes for quantifying trace amount of water in organic solvents.
Adaptive fault‐tolerant formation control for quadrotors with actuator faults
Authors: Liu Wanzhang , Zhang Ke , Jiang Bin , Yan Xinggang
Published: February 2019

In this paper, we investigate the fault‐tolerant formation control of a group of quadrotor aircrafts with a leader. Continuous fault‐tolerant formation control protocol is constructed by using adaptive updating mechanism and boundary layer theory to compensate actuator fault. Results show that the desired formation pattern and trajectory under actuator fault can be achieved using the proposed fault‐tolerant formation control. A simulation is conducted to illustrate the effectiveness of the method.
Modelling Coupled Ion Motion in Electrolyte Solutions for Lithium‐Sulfur Batteries
Authors: Osella Silvio , Minoia Andrea , Quarti Claudio , Cornil Jérôme , Lazzaroni Roberto , Goffin Anne‐Lise , Guillaume Maxime , Beljonne David
Published: February 2019

We model coupled ion transport in representative electrolyte solutions for Li−S batteries by applying molecular dynamic (MD) simulations on systems of increasing complexity, namely going from solutions of the Li2S4 salt in pure tetraethylene glycol dimethyl ether (TEGDME) and 1,3‐dioxolane (DOL) solvents, to Li2S4 in solvent mixtures, and finally incorporating lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as a reservoir of Li‐ions. While the motion of Li2S4 salt in DOL is predominantly vehicular, it is governed by a hopping regime in the more viscous TEGDME solvent. Most importantly, when the two salts are mixed, the presence of the TFSI anions does not slow down the diffusion of the polysulfide anion.
Learning from a failure in threat assessment: 11 questions and not enough answers
Authors: Goodrum Sarah , Evans Mary K. , Thompson Andrew J. , Woodward William
Published: February 2019

Threat assessment theory and practice have evolved significantly since Columbine. The US Secret Service's guidelines for threat assessment include 11 questions that school officials should ask to identify, investigate, and manage students of concern. Yet, no research examines how school officials implement these questions. This qualitative case study examines the way that school officials used the 11 questions with a student of concern, who underwent a threat assessment and 3 months later shot and killed a classmate and himself on school grounds. The data include deposition testimony from 12 school and district officials and more than 8,000 pages of records in the case. For each of the 11 questions, the findings reveal what the threat assessment team knew and might have learned; the findings also demonstrate the importance of multiple sources of information, a multidisciplinary team, and an investigative mindset. The questions may prove difficult to answer in “loosely coupled” systems, like schools, where information is unintentionally lost due to the organization's structural hierarchy, specialization of tasks, and heavy workloads. The findings provide critical lessons learned for threat assessment, information gathering, and violence prevention in schools.
The use of apocynin inhibits osteoclastogenesis
Authors: Soares Mariana Pena Ribeiro , Silva Danielle Pereira , Uehara Isadora Akemi , Ramos Erivan Schnaider , Alabarse Paulo Vinicius Gil , Fukada Sandra Yasuyo , da Luz Felipe Cordero , Vieira Leda Quercia , Oliveira Ana Paula Lima , Silva Marcelo José Barbosa
Published: February 2019

Reactive oxygen species (ROS) are produced by NADPH oxidase (NOX), an enzyme that reduces oxygen by using NADPH as a substrate. Apocynin (APO) is a catechol that is used as a NOX inhibitor, and N‐acetyl‐cysteine ​​(NAC) can reduce intracellular ROS levels. In this work, the effect of APO and NAC on osteoclast formation were evaluated. APO and NAC significantly decreased the number of tartrate‐resistant acid phosphatase (TRAP)‐positive cells and the osteoclast area. We analyzed bone‐marrow derived monocyte‐macrophages (BMMs) that differentiated into osteoclasts after RANKL stimulation. Stimulation was associated with either APO or NAC treatment and osteoclastogenesis marker expression, including NFATc1, MMP‐9, and DC‐STAMP, was evaluated. APO decreased the intracellular calcium concentration by calcium channels other than ITPR1 and TPC2. On the other hand, APO reduced Tnfrsf11a (RANK) expression and did not alter Fam102a (EEIG1) expression. Therefore, our results demonstrate that APO inhibits osteoclastogenesis by the RANK‐RANKL‐related signaling pathways, decreases osteoclast markers, and reduces intracellular calcium concentration.
A Flower‐like Bismuth Oxide as an Efficient, Durable and Selective Electrocatalyst for Artificial N2 Fixation in Ambient Condition
Authors: Chang Bing , Liu Qin , Chen Ninghua , Yang Yingchun
Published: February 2019

Ammonia is a basic industrial chemical, which is widely used in industry and agriculture. Traditional Haber–Bosch N2 fixation process is not environmentally friendly, which not only excessively consumes energy, but releases enormous amount of greenhouse gas. Electrochemical N2 reduction is an ideal alternative to N2 fixation, but it requires effective electrocatalyst for N2 reduction reaction (NRR). Herein, we develop a flower‐like β‐Bi2O3 catalyst for artificial N2 fixation with outstanding NRR performance and selectivity in ambient condition. This β‐Bi2O3 nanoflower shows an excellent NH3 yield of 19.92 μg h−1 mg−1cat. and Faradaic Efficiency of 4.3 % at −0.8 V in 0.1 M Na2SO4 solution, better than most reported NRR electrocatalysts. This electrocatalyst also exhibits superb electrochemical stability and durability.
Dimensionality Expansion of a Butterfly Shaped Pd4 Framework: Constructing Edge‐Sharing Pd6 Tetrahedra
Authors: Shimamoto Kento , Sunada Yusuke
Published: February 2019

The construction of well‐defined transition‐metal clusters has attracted substantial attention due to their unique chemical and/or physical properties. Metal clusters with 1D or 2D structures are now accessible by template‐synthesis methods, in which multiple metal atoms are arranged with the aid of template molecules and their 1D or 2D structures. However, the rational synthesis of 3D clusters remains challenging, mostly due to a lack of appropriate template molecules. Herein, we report the rational synthesis of a 2D butterfly shaped Pd4 framework (2) and 3D edge‐sharing Pd6 tetrahedra (5) by treatment of easily available organosilicon compounds with Pd(CNtBu)2. The diphenylsilylene moiety thereby serves as the key component to generate the butterfly structure of the Pd4 clusters in 2. A dimensionality expansion, induced by two Cl atoms, of two butterfly shaped Pd4 subunits supported by two diphenylsilylene moieties afforded the edge‐sharing tetrahedral architecture of the Pd6 cluster in 5.
Resin Swelling in Mixed Solvents Analysed using Hansen Solubility Parameter Space
Authors: Ran Yanrui , Byrne Fergal , Ingram Ian D. V. , North Michael
Published: February 2019

The swelling of resins (Merrifield and HypoGel 200) in mixtures of two solvents was generally found not to vary linearly with the relative amount of each solvent in the mixture. Hansen solubility parameter (HSP) space could be used to define high, medium and low swelling regions for each resin. The variation of resin swelling with binary solvent composition could then be explained based on the HSP parameters of the two solvents and the way in which the line connecting the points corresponding to the two pure solvents bisected the swelling region for the resin. The applicability of the methodology was demonstrated by showing that an appropriate mixture of two green solvents was more effective for solid‐phase peptide synthesis on Merrifield resin than use of either individual solvent and could completely replace the use of traditional polar aprotic and chlorinated solvents for this application. It was also shown that the high resin swelling area of Merrifield resin can be used to predict mixtures of green solvents that will dissolve linear, unfunctionalised polystyrene.
Iridium(I)‐Catalyzed C−H Borylation in Air by Using Mechanochemistry
Authors: Pang Yadong , Ishiyama Tatsuo , Kubota Koji , Ito Hajime
Published: February 2019

Mechanochemistry has been applied for the first time to an iridium(I)‐catalyzed C−H borylation reaction. By using either none or just a catalytic amount of a liquid, the mechanochemical C−H borylation of a series of heteroaromatic compounds proceeded in air to afford the corresponding arylboronates in good‐to‐excellent yields. A one‐pot mechanochemical C−H borylation/Suzuki–Miyaura cross‐coupling sequence for the direct synthesis of 2‐aryl indole derivatives is also described. The present study constitutes an important milestone towards the development of industrially attractive solvent‐free C−H bond functionalization processes in air.
Identifying Left Ventricular Thrombi
Authors: EZEKOWITZ M. D.
Published: February 2019

A number of imaging techniques are available for the identification of left ventricular thrombi. Echocardiography is the technique of choice because of its wide availability, noninvasiveness, and relative low cost. The accuracy of infonnation from echocardiography depends on the skill of the technician and quality of equipment. Platelet scintigraphy, which reflects activity on the thrombus surface, plays a complementary role to echocardiography in detecting thrombi. Magnetic resonance imaging and computed tomography are potentially useful. Contrast ventriculography lacks sensitivity and specificity, and radio nuclide angiography lacks sensitivity in the diagnosis of left ventricular thrombi.
Thrombolytic Agents: Balancing Cost, Efficacy, and Side Effects
Authors: MARDER V. J.
Published: February 2019

Balancing the benefits, risks, and cost of thrombolytic treatment is a complex issue which depends considerably upon the variable threat of the thrombus to organ physiology and patient survival. For example, after deep vein thrombosis (DVT), the major risk is long‐term disability due to the postphlebitic syndrome, while in pulmonary embolism (PE) patients, the risks concern short‐term mortality and impaired pulmonary physiology. Thus, for treating DVT or PE, the question is whether thrombolytic therapy would be valuable in addition to other antithrombotic approaches. Clearly, the best indication for thrombolytic therapy is in acute myocardial infarction (MI) patients, because this therapy has the potential for reducing coronary artery thrombus mortality. In acute MI the major issues concern the choice of thrombolytic agent and the relative merits of nonpharmacologic interventions such as angioplasty and bypass surgery. An optimal window of treatment opportunity exists for all of the indications. The window is shortest for MI, intermediate for PE, and longest for DVT patients.
Seeing the signs of cancer’s metabolic changes
Authors: Nelson Bryn
Published: February 2019

This news section is written by a medical journalist and offers Cancer Cytopathology readers timely information on events, issues, and personalities of interest to the subspecialty. This edition explores the growing body of research that suggests that early signs of cancer can be spotted through metabolic changes in aberrant cells.
Differential expression of neurexin genes in the mouse brain
Authors: Uchigashima Motokazu , Cheung Amy , Suh Julie , Watanabe Masahiko , Futai Kensuke
Published: February 2019

Synapses, highly specialized membrane junctions between neurons, connect presynaptic neurotransmitter release sites and postsynaptic ligand‐gated channels. Neurexins (Nrxns), a family of presynaptic adhesion molecules, have been characterized as major regulators of synapse development and function. Via their extracellular domains, Nrxns bind to different postsynaptic proteins, generating highly diverse functional readouts through their postsynaptic binding partners. Not surprisingly given these versatile protein interactions, mutations and deletions of Nrxn genes have been identified in patients with autism spectrum disorders, intellectual disabilities, and schizophrenia. Therefore, elucidating the expression profiles of Nrxns in the brain is of high significance. Here, using chromogenic and fluorescent in situ hybridization, we characterize the expression patterns of Nrxn isoforms throughout the brain. We found that each Nrxn isoform displays a unique expression profile in a region‐, cell type‐, and sensory system‐specific manner. Interestingly, we also found that αNrxn1 and αNrxn2 mRNAs are expressed in non‐neuronal cells, including astrocytes and oligodendrocytes. Lastly, we found diverse expression patterns of genes that encode Nrxn binding proteins, such as Neuroligins (Nlgns), Leucine‐rich repeat transmembrane neuronal protein (Lrrtms) and Latrophilins (Adgrls), suggesting that Nrxn proteins can mediate numerous combinations of trans‐synaptic interactions. Together, our anatomical profiling of Nrxn gene expression reflects the diverse roles of Nrxn molecules.
Architecture for diverse modulation techniques in SDR
Authors: Savitha G. , Karthikeyan S.
Published: February 2019

Software defined radio (SDR) technology supports multiple air interfaces and modulation formats for wireless devices, which is vital when paralleled with the proliferation of wireless standards. To achieve such flexibility and functionality, SDR uses Field Programmable Gate Array (FPGA) with reconfigurable fabric. In the proposed work, different modulation techniques available in SDR are presented. Design and implementation procedure on Xilinx FPGA are also discussed. The VHDL hardware description language is used for designing and implementing the various modulators. The Xilinx EDA tool is used to synthesize the proposed one. The reconfiguration of bits is used to select the various modulation techniques dynamically with the help of Xilinx software. This proposed design makes the implementation of SDR based modulators very simple and fast.
A Straightforward Route to Aromatic Excited States in Molecular Motors that Improves Photochemical Efficiency
Authors: Wang Jun , Oruganti Baswanth , Durbeej Bo
Published: February 2019

The many successful efforts to optimize the thermal steps that are part of the reaction cycles of most light‐driven rotary molecular motors have not been followed by studies providing a similarly detailed understanding of how the efficiency of the photochemical steps that actually power the motors can be improved. Against this background, we herein use computational methods to investigate the merits of an approach to increase the quantum yields of E/Z‐photoisomerization‐based motors by enabling one of their two moieties to become aromatic in the photoactive excited state. Through quantum chemical calculations, a straightforward route to excited states of this type is found for motors where one moiety can be transformed into an aromatic anion by an electron donor at the other moiety. Furthermore, through molecular dynamics simulations, motors operated in such excited states are indeed predicted to be much more efficient than similar motors operated in the absence of excited‐state aromaticity.
Cytological features of uterine tumors resembling ovarian sex‐cord tumors in liquid‐based cervical cytology: a potential pitfall. Report of a unique and rare case
Authors: Dubruc Estelle , Alvarez Flores Maria Teresa , Bernier Yannick , Gherasimiuc Lucia , Ponti Alexandre , Mathevet Patrice , Bongiovanni Massimo
Published: February 2019

Uterine tumors resembling ovarian sex‐cord tumors (UTROSCTs) are rare uterine neoplasms of uncertain etiology that resemble the sex cord tumors of the ovary and display a combined sex cord, epithelial, and smooth muscle immunophenotype. Most tumors are associated with a benign clinical course. We report the first cytological description of uterine UTROSCTs in liquid‐based cervical cytology (LBC). A menopausal woman was discovered to have a uterine intraluminal polypoid mass protruding through the vagina. A Pap test was performed, and the LBC preparation showed isolated tumor cells with scant cytoplasm and slightly irregular, ovoid nuclei with fine chromatin and small nucleoli. Final histological evaluation identified a UTROSCT. This diagnostic possibility, albeit rare, should be included in the differential diagnosis when isolated malignant‐appearing adenocarcinomatous cells are seen in women in the above scenario. As these features are not specific, they may result in misinterpretation with tumors that are more common and aggressive.
Image quantification technology of the heterochromatin and euchromatin region for differential diagnosis in the lobular endocervical glandular hyperplasia
Authors: Kimura Fumikazu , Kobayashi Takaki , Kanai Ryo , Kobayashi Yukihiro , Yuhi Ohtani , Ota Hiroyoshi , Yamaguchi Masahiro , Yokokawa Yoshiharu , Uehara Takeshi , Ishii Keiko
Published: February 2019

Background

Lobular endocervical glandular hyperplasia (LEGH) was first described by Nucci et al. in 1999 and is believed to be a precancerous lesion of minimal deviation adenocarcinoma and gastric‐type adenocarcinoma in the uterine cervix. LEGH lesions do not always exhibit apparent cellular and structural atypia, so are difficult to distinguish from normal endocervical cells (EC cells) with cytological examination. Therefore, we often struggle to make a definite diagnosis of LEGH.

Methods

We used microscopy images of cytological specimens that were diagnosed as EC cells and LEGH cells. Signal intensity in whole nuclear area and in heterochromatin and euchromatin regions, euchromatin area ratio, and nuclear morphological features were quantified in each cell nucleus of the cases. Statistical analyses were conducted to determine statistical significance. Finally, we performed linear support vector machine (LSVM) modeling as a discriminant analysis using the quantified features.

Results

Signal intensity in whole nuclear area, and heterochromatin and euchromatin regions of EC cell nuclei were higher than that of the LEGH cell nuclei. Morphologically, EC cell nuclei were larger than LEGH cell nuclei, and nuclei of LEGH cells had irregular nuclear respectively membrane structure and an elongated shape. The LSVM accuracy of 10‐fold cross validation and leave‐one‐case‐out cross‐validation (LOCOCV) using all measured features were 84.7% to 89.3% and 78.6% to 86.0%, respectively.

Conclusions

The LVSM analysis using features extracted from signal intensity and morphological analysis was useful for discrimination of EC cells vs LEGH cells. We therefore believe that this image analysis method could be used for early detection of LEGH.
Cytomorphological spectrum of scalp lesions in the population of a developing country: A retrospective study
Authors: Sharma Pooja , Pathak Priya , Goyal Aditi , Sharma Sonal
Published: February 2019

BACKGROUND

Scalp lesions are frequently encountered in clinical practice. Fine‐needle aspiration cytology (FNAC) can characterize most of these lesions; however, there is little published work on cytology of scalp lesions.

METHODS

Records of all the patients subjected to FNAC from January 2011 to August 2016 were retrieved from the archives of the Cytopathology section of our Institute. Out of the 71 852 cases reviewed, 896 patients, who presented with palpable scalp lesions, were included in the study. Aspirates were obtained with a 23‐gauge needle attached to a 10 mL disposable plastic syringe. May–Grünwald–Giemsa stained and Pap stained slides were prepared. Special stains and immunocytochemical analysis were done when necessary.

RESULTS

Out of the 896 cases of aspirates from scalp lesions, 155 (17.2%) aspirates were found to be inadequate for diagnosis. One hundred and fifty‐seven (21%) out of 741 adequate aspirates showed features of inflammatory or reactive pathology comprising of abscesses (57), cystic lesions (24), tubercular lesions (16), and reactive lymphadenopathy (66). Four hundred and fifteen (56%) aspirates revealed a tumor‐like etiology comprising of epidermal cyst (395), sebaceous cyst (4), dermoid cyst (1), calcinosis (7), vascular malformation (7), hematoma (5), and juvenile xanthogranulomatous lesion (1). Tumorous lesions formed 22.3% of the aspirates. Of these, 7 cases (4.2%) were of metastases to the scalp.

CONCLUSION

In a developing country, FNAC is a useful and cost‐effective investigation for the diagnosis of a wide spectrum of scalp lesions. It allows rapid diagnosis and permits timely intervention thereby preventing complications due to delay in diagnosis.
Estimating effects of arable land use intensity on farmland birds using joint species modeling
Authors: Stjernman Martin , Sahlin Ullrika , Olsson Ola , Smith Henrik G.
Published: February 2019

Declines in European farmland birds over past decades have been attributed to the combined effects of agricultural intensification and abandonment. Consequently, aspirations to stop declines should focus attention on reversing these changes through voluntary or policy‐driven interventions. The design of such interventions should ideally be informed by scientific knowledge of which aspects of the transformation of agricultural landscapes have contributed to the farmland bird declines. Declines may be associated with loss of natural habitats or the intensification and homogenization of land use management on production land, and furthermore, these changes may interact. Here, we applied an orthogonal design exploiting spatial variation in land use in a major agricultural region of Sweden to seek evidence for benefits to farmland birds of reversing some of the intensifications on and among arable fields and whether effects are modified by the availability of seminatural habitats (pastures and field borders) in the landscape. We accounted for the potentially confounding effect of interactions between species by using a joint species distribution model explicitly controlling for additional variation and covariation among species. We found that interventions aimed specifically at land in production could provide benefits to farmland birds. Landscapes with a higher proportion leys or fallows and/or with a more diverse set of crops held higher abundances of most farmland birds. However, effects were only apparent in landscapes with low availability of seminatural habitats and were sometimes even negative in landscapes with high amounts of such habitats, demonstrating context dependence. Even if we found little evidence of interactions between species, the joint modeling approach provided several benefits. It allowed information to be shared between species making analyses robust to uncertainty due to low abundances and provided direct information about the mean and variability in effects of studied predictors among species. We also found that care needs to be taken regarding prior and distributional assumptions as the importance of species interactions might otherwise be overstated. We conclude that this approach is well suited for evaluating agricultural policies by providing evidence for or against certain interventions or to be linked to policy scenarios of land use change.