bluuebunny/crossref_metadata_2025 huggingface dataset:
Illicit Tramadol Tablets Traded in Kuwait during 2016 – 2017; Their Analysis by GC/MS and Classification
Authors: Al-Abkal N. A. , Kh Metwally E. , Alezzbawy S. R. , OrabiKh Y. , Alshammari Sh. H.
Published: June 2020

Aim: To determine the quality and quantity of tramadol traded in the State of Kuwait and its classification.

Study Design: Collected samples of tramadol tablets seized in Kuwait during 2016 & 2017 and a pure tramadol standard, all have been analyzed in the Forensic Laboratories.

Place and Duration of Study: All analyses were conducted during 2016–2017 in the Forensic Laboratories of the General Department of Criminal Evidences – Ministry of Interior – State of Kuwait.

Methodology: A total of fifty samples of non-pure tramadol tablets seized in Kuwait during the year 2016 & 2017 and one pure standard, all have been analyzed by using Gas Chromatography/Mass Spectrometry (GC/MS).

Results: The fifty collected samples of tramadol could be classified into three groups: The first (Red) group is recorded in 42 samples (84 % of samples) with concentration range between 0.1 mg/ml and 1.1 mg/ml; it has a red color known as (strawberry) which is a street name; it is mixed with carboxylic and silicic acids, the second (White)group is detected in 3 samples, with two different concentrations: One sample has 0.3 mg/ml and the other two samples have 0.4 mg/ml; it is mixed with acidic substances and newly identified venlafaxine and the third (Medical) group is recorded in 5 samples as a pharmaceutical drug with different colors and shapes, one of them was detected as acetaminophen, and hence deleted, while the concentrations recorded for all four tablets are 0.2 mg/ml; it is mixed with acidic substances and venlafaxine.

Conclusion: The main types of tramadol frequently traded in the State of Kuwait, can be divided into the following three groups: First Red Group includes red tablets which represent the most common type traded from Egypt, India and China according to the statistics of United Nations 2013(18), with purity range from 60% to 201%. The Second White Group includes all white tablets which are much less traded than the red tablets, with purity range from 58% to 123% and the Third Medical Group includes adulterated medical tablets which have purity range as 26%.
Economic and Environmental Implications of Trawl Fishing: An Analysis in Munambam Fishing Harbour on the South West Coast of India
Authors: Aswathy N. , Narayanakumar R.
Published: June 2020

Kerala state in the Southwest coast of India is an important maritime state and mechanized trawlers are the principal fishing units in the state. Since 2007, high speed engines were introduced in the trawl fishing sector which yielded higher hauling speed compared to the indigenous engines. Munambam fishing harbour is one of the biggest fishing harbours in Kerala where more than 90% of the mechanized trawlers operate with high speed engines. The high-speed trawlers were criticized for their environmental impacts to marine resources in terms of overexploitation and high fuel consumption. The fuel consumption of fishing units has economic, social and environmental implications with regard to sustainable fish harvests and livelihood security of fishermen. The objective of the study was to assess the economic and environmental implications of high speed trawl fishing units in Munambam fishing harbour on the South west coast of India. The data were collected from 90 boat operators from Munambam fishing harbour during the 2017-2018 fishing season. The samples were drawn randomly from the boat owners or boat operators. The results of the multiple regression analysis used to assess the factors affecting fish catches by high speed trawlers indicated that skipper’s experience and fuel consumption had positive and significant influence on fish catch and 1% increase in quantity of fuel used led to an increase of 0.363% in gross income. The carbon dioxide emissions from the trawlers were also estimated to assess the environmental implications.
Pathogenesis and Possible Drug Targets for Covid-19
Authors: Kumar N. Ramesh , Chitra S.
Published: June 2020

Coronavirus (CoVs) is a large family of enveloped, single-stranded, positive-sense RNA viruses that infect a wide range of vertebrates. They are extensively found in bats and also in many other birds and mammals including humans. SARS-CoV-2 is a global pandemic and originated from Wuhan States of China. The SARS-CoV-2 is more genetically similar to zoonotic SARS-CoV and less similar to MERS-CoV.  The viral surface spike protein of SARS-CoV-2 binds to the human angiotensin-converting enzyme-2 (ACE-2) receptor of Type II alveolar cells of the lungs and it appears to be the major portal of entry by this virus.  The subsequent activation of the spike protein by transmembrane protease-2 and in addition to lung, ACE-2 is highly expressed in heart followed by kidney and intestinal epithelium. SARS-CoV-2 infects more men than women due to ACE-2 receptor on the cells increased with age and generally it was higher in men than in women. The incubation period for this virus varies from place to place and asystematic symptoms are also commonly seen in infected patients. There are a number of pharmaceuticals already being tried and are in different phase levels of testing, but a better understanding of the underlying pathobiology is required. In this circumstance, this article will briefly review the underlying principle for ACE-2 receptor as a specific target. Despite ACE-2 serving as the portal for infection, the role of ACE inhibitors or angiotensin receptor blockers requires further investigation.
Prevalence of Underweight and Associated Factors among Lactating Women in Ethiopia: A Mini-review
Authors: Sserwanja Quraish , Kawuki Joseph
Published: June 2020

Nutritional status is considered as one of the key indicators of the overall wellbeing of a population. Lactating women and children are among the most vulnerable groups due to their higher nutritional needs and detrimental effects of poor nutrition on their health. Lactating women have increased nutritional needs and if not well met, breast milk quality and quantity are negatively affected, which leads to increased risk for child morbidity and mortality. Studies have been done in the different regions of Ethiopia to assess the nutritional status among lactating women and have reported various prevalence and different associated factors. Despite the different efforts to improve nutrition in Ethiopia, the prevalence of underweight is still high, with most regions having a higher prevalence than the documented 5-20% of African women.

We aimed to review the prevalence and associated factors of underweight among lactating women in Ethiopia. We used literature searched from key databases such as Google Scholar, Web of Science, among others, to collect relevant information about the prevalence of underweight among pregnant women in Ethiopia.

The mini-review identified the highest prevalence at 50.6% in the Northern parts and the lowest at 17.4% in the Southern parts of Ethiopia. Several factors were identified to be associated with underweight among lactating women in Ethiopia including; dietary diversity score, household food security, family income, place of delivery, nutritional education programs and antenatal care attendance. This implies the need for targeted programs/policies to promote household food security and family income, community nutritional education, and nutritional counselling during antenatal care attendance. Besides, there is a need to conduct national and regional studies to inform policy further since there were more studies done in the Southern parts of the Country with less information from other regions.
Advanced Semiconductor Design through Specialized Printable Conductive Layer
Authors: Rodriguez Rennier , Gomez Frederick Ray , Maming Maiden Grace
Published: June 2020

Semiconductor package miniaturization and thinning have become of particular interest among semiconductor manufacturing industries, with each manufacturing company having specific approach and technical directions in providing unique solutions in their products. The paper provides a specialized design of manufacturing flow for semiconductor device through advanced fabrication method using stencil printing. The advanced process would significantly reduce the carrier thickness for the overall package height configuration of the device. The implementation of the specialized design and process would mitigate common assembly barriers and defects related in producing thin devices, hence, enabling cost-saving realization and manufacturing solution to package thinning and miniaturization with multiple input/output (I/O) requirements.
Assessment of Coliforms Bacteria Contamination in Lake Tanganyika as Bioindicators of Recreational and Drinking Water Quality
Authors: Niyoyitungiye Lambert , Giri Anirudha , Ndayisenga Marc
Published: June 2020

Worldwide coliform bacteria are used as indicators of environmental and fecal contamination and hence, the possible presence of pathogenic organisms. As most people living on the shores of Lake Tanganyika use its water for cooking, drinking and washing; the monitoring of organisms indicating water pollution is more predictive of the presence of certain pathogens to protect public health. This study was carried out along the Burundian coast at 4 sampling sites (Kajaga, Nyamugari, Rumonge and Mvugo) in the months of January, February and March 2018, to assess quantitatively the presence of coliform bacteria in comparison to the standards recommended by BIS-10500 (1991, 2012) and WWF-Pakistan (2007) for drinking and recreational water quality and to sensitize the populace using the untreated water about the potential health risks. The ColonyForming Unit (CFU) method was used and the results showed that total coliform bacteriaobtained was in the range of 9000 to 60000 CFU/100 mLand are indicative of environmental contamination of all sampling stations with an average of 33250 CFU/100 mL. Fecal coliform bacteria ranged from 0 to 5000 CFU/100 mL with an overall average of 2000 CFU/100 m Land Kajaga site appeared free of contamination as fecal coliform count there was nil. The Escherichia coli count recorded ranged from 0 to 3000 CFU/100 mL with an average of 1350 CFU/100 mL. At Kajaga stations, Escherichia coli count was 0 and therefore there is no evidence of recent fecal contamination. Thus, if only fecal contamination is taken into account, the water from Kajaga station can be considered as safe for drinking and bathing purposes but incidentally total coliforms were found at Kajagastation. The water from all sampling stations require treatment before any use.
Homophobic bullying victimization trajectories: The roles of perpetration, sex assigned at birth, and sexuality
Authors: Hatchel Tyler , Ingram Katherine M. , Huang Yuanhong , Espelage Dorothy L.
Published: June 2020

There is a paucity of research on developmental trajectories of bias‐based aggression. We examined homophobic bullying victimization trajectories among high school students (N = 3,064; M age = 13.67; Girls = 50.2%) and how these developmental pathways vary as a function of factors like homophobic bullying perpetration, sex assigned at birth, and sexuality. Using data from a 3‐wave longitudinal investigation over a 2‐year period, we utilized latent growth mixture modeling to explore the aforementioned trajectories. Findings suggested that there were three distinct classes characterized by high initial rates and declines over time, low initial rates, and increases over time, and low, stable, rate across time. Furthermore, results indicated that homophobic bullying perpetration, sex assigned at birth, and sexuality all predicted class membership.
Parallelized Impedance‐Based Platform for Continuous Dose‐Response Characterization of Antischistosomal Drugs
Authors: Ravaynia Paolo S. , Lombardo Flavio C. , Biendl Stefan , Dupuch Matthias A. , Keiser Jennifer , Hierlemann Andreas , Modena Mario M.
Published: June 2020

Schistosomiasis is an acute and chronic disease caused by tropical parasitic worms of the genus Schistosoma, which parasitizes annually over 200 million people worldwide. Screening of antischistosomal compounds is hampered by the low throughput and potential subjectivity of the visual evaluation of the parasite phenotypes, which affects the current drug assays. Here, an impedance‐based platform, capable of assessing the viability of Schistosoma mansoni schistosomula exposed to drugs, is presented. This automated and parallelized platform enables unbiased and continuous measurements of dose–response relationships for more than 48 h. The platform performance is established by exposure of schistosomula to three test compounds, praziquantel, oxethazaine, and mefloquine, which are known to affect the larvae phenotypes. The system is thereafter used to investigate the response of schistosomula to methiothepine, an antipsychotic compound, which causes complex drug‐induced effects. Continuous monitoring of the parasites reveals transient behavioral phenotypes and allows for extracting temporal characteristics of dose–response curves, which are essential for selecting drugs that feature high activity and fast kinetics of action. These measurements demonstrate that impedance‐based detection provides a wealth of information for the in vitro characterization of candidate antischistosomals and, represents a promising tool for the identification of new lead compounds.
Translational Neuroelectronics
Authors: Jastrzebska‐Perfect Patricia , Chowdhury Shilpika , Spyropoulos George D. , Zhao Zifang , Cea Claudia , Gelinas Jennifer N. , Khodagholy Dion
Published: June 2020

Neuroelectronic devices are critical for the diagnosis and treatment of neuropsychiatric conditions, and are hypothesized to have many more applications. A wide variety of materials and approaches have been utilized to create innovative neuroelectronic device components, from the tissue interface and acquisition electronics to interconnects and encapsulation. Although traditional materials have a strong track record of stability and safety within a narrow range of use, many of their properties are suboptimal for chronic implantation in body tissue. Material advances harnessed to form all the components required for fully integrated neuroelectronic devices hold promise for improving the long‐term efficacy and biocompatibility of these devices within physiological environments. Here, it is aimed to provide a comprehensive overview of materials and devices used in translational neuroelectronics, from acquisition and stimulation interfaces to methods for power delivery and real time processing of neural signals.
Controlled Apoptosis of Stromal Cells to Engineer Human Microlivers
Authors: Chen Amanda X. , Chhabra Arnav , Song Hyun‐Ho Greco , Fleming Heather E. , Chen Christopher S. , Bhatia Sangeeta N.
Published: June 2020

Engineered tissue models comprise a variety of multiplexed ensembles in which combinations of epithelial, stromal, and immune cells give rise to physiologic functions. Engineering spatiotemporal control of cell–cell and cell–matrix interactions within these 3D multicellular tissues would represent a significant advance for tissue engineering. In this work, a new method, entitled CAMEO (Controlled Apoptosis in Multicellular tissues for Engineered Organogenesis) enables the noninvasive triggering of controlled apoptosis to eliminate genetically engineered cells from a pre‐established culture. Using this approach, the contribution of stromal cells to the phenotypic stability of primary human hepatocytes is examined. 3D hepatic microtissues, in which fibroblasts can enhance phenotypic stability and accelerate aggregation into spheroids, are found to rely only transiently on fibroblast interaction to support multiple axes of liver function, such as protein secretion and drug detoxification. Due to its modularity, CAMEO has the promise to be readily extendable to other applications that are tied to the complexity of 3D tissue biology, from understanding in vitro organoid models to building artificial tissue grafts.
Controlling the Thermoelectric Properties of Organometallic Coordination Polymers via Ligand Design
Authors: Liu Zilu , Liu Tianjun , Savory Christopher N. , Jurado José P. , Reparaz Juan Sebastián , Li Jianwei , Pan Long , Faul Charl F. J. , Parkin Ivan P. , Sankar Gopinathan , Matsuishi Satoru , Campoy‐Quiles Mariano , Scanlon David O. , Zwijnenburg Martijn A. , Fenwick Oliver , Schroeder Bob C.
Published: June 2020

Organometallic coordination polymers (OMCPs) are a promising class of thermoelectric materials with high electrical conductivities and thermal resistivities. The design criteria for these materials, however, remain elusive and so far material modifications have been focused primarily on the nature of the metal cation to tune the thermoelectric properties. Herein, an alternative approach is described by synthesizing new organic ligands for OMCPs, allowing modulation of the thermoelectric properties of the novel OMCP materials over several orders of magnitude, as well as controlling the polarity of the Seebeck coefficient. Extensive material purification combined with spectroscopy experiments and calculations furthermore reveal the charge‐neutral character of the polymer backbones. In the absence of counter‐cations, the OMCP backbones are composed of air‐stable, ligand‐centered radicals. The findings open up new synthetic possibilities for OMCPs by removing structural constraints and putting significant emphasis on the molecular structure of the organic ligands in OMCP materials to tune their thermoelectric properties.
Precisely Determined Water Permeabilities of Sub‐100 nm Nanochannels
Authors: Xu Fang‐Fang , Liu Zhi‐Wei , Huang Ran , Zhang Jia‐Ming , Liu Jie , Hu Zheng‐Guo , Ma Jie , Yao Hui‐Jun , Sun You‐Mei , Chen Yong‐Hui , Zhang Sheng‐Xia , Mo Dan , Duan Jing‐Lai
Published: June 2020

Membrane ultrafiltration is an extensively used technique for water purification and hence understanding the water flow confined in nanochannels is of vital importance. As a key parameter, water permeability has been the focus of fundamental researches and technical applications. However, water permeability in sub‐100 nm regime is not yet well understood as evidenced by the previously published data which are divergent from theory. Here, the precise determination of water permeabilities of sub‐100 nm nanochannels is reported. This is achieved by the proposed innovative pore diameter‐calibration method with excellent accuracy through replicating the pore geometry, and using the nanoporous ion track‐etched membrane as a model system which features well‐defined, cylindrical, straight, and equally sized nanochannels. Thanks to this accurate calibration method, the measured permeabilities show a remarkably improved precision as compared to the previously reported data. In addition, the measured permeabilities of the ultrafiltration channels are lower than the theoretical predictions. The discrepancy is explained under the framework of the wettability effect. It is expected that the work will shed light on a controversy over a decrease or increase in water permeability of ultrafiltration membranes and also guide the design of ultrafiltration membranes for water purification and separation applications.
Binding Affinity and Conformational Preferences Influence Kinetic Stability of Short Oligonucleotides on Carbon Nanotubes
Authors: Alizadehmojarad Ali A. , Zhou Xingcheng , Beyene Abraham G. , Chacon Kevin E. , Sung Younghun , Pinals Rebecca L. , Landry Markita P. , Vuković Lela
Published: June 2020

DNA polymer‐wrapped single‐walled carbon nanotubes (SWNTs) finds a widespread use in a variety of nanotechnology applications. Molecular dynamics (MD) simulations and experiments are used to explore the relationship between structural conformation, binding affinity, and kinetic stability for short single‐stranded oligonucleotides adsorbed on SWNTs. The conformation of 36 oligonucleotide sequences on (9,4) SWNT is computationally screened, where the polymer lengths are selected so the polymers can, to a first approximation, wrap once around the SWNT circumference. The identified conformations can be broadly classified into “rings” and “non‐rings.” Then, 2D conformational free energy landscapes for selected sequences are obtained by temperature replica exchange calculations. Propensity for “ring” conformations are driven primarily by sequence chemistry and the ability of the polymer to form compact structures. However, ring‐formation probability is found to be uncorrelated with free energy of oligonucleotide binding to SWNTs (∆Gbind). Conformational analyses of oligonucleotides, computed free energy of binding of oligonucleotides to SWNTs, and experimentally determined kinetic stability measurements show that ∆Gbind is the primary correlate for kinetic stability. The probability of the sequence to adopt a compact, ring‐like conformation is shown to play a secondary role that still contributes measurably and positively to kinetic stability.
Quasi‐2D Crystalline γ‐Alumina Grown by Graphene‐Assisted Atomic Layer Deposition
Authors: Kheirandish Elaheh , Schofield Marvin , Gajdardziska‐Josifovska Marija , Kouklin Nikolai
Published: June 2020

This study presents a facile high‐yield bottom‐up fabrication and morphology‐structure investigations of a free‐standing network of multi‐layer quasi‐2D flakes consisting of intrinsically nonlayered γ‐Al2O3. The synthesis comprises a multi‐cycle atomic layer deposition (ALD) of amorphous alumina that uses an interconnected graphene network as a growth scaffold followed by ≈800 °C air anneal. The structures are studied by X‐ray diffraction, selected area electron diffraction, and high‐resolution transmission electron microscopy, while electric properties are assessed with the help of two‐terminal dc‐transport measurements. The individual flakes comprise nanocrystalline phase cubic spinel γ‐Al2O3 with a close‐packed cubic texture in the 〈111〉cubic ALD‐induced growth direction. The charge transport is confirmed to be Ohmic with the room temperature electrical conductivity approaching ≈10−8 S m−1. This work opens a door to a low‐cost highly scalable synthesis of a variety of quasi‐2D metal oxides for widespread uses ranging from support material, sensing to environmental remediation.
Interface Engineering and Epitaxial Growth of Single‐Crystalline Aluminum Films on Semiconductors
Authors: Zhang Kedong , Xia Shunji , Li Chen , Pan Jiahui , Ding Yuanfeng , Lu Ming‐Hui , Lu Hong , Chen Yan‐Feng
Published: June 2020

Single crystalline aluminum (Al) films are grown on GaAs substrates by molecular beam epitaxy. The high crystalline quality and sharp interfaces of the epitaxial Al films are confirmed by high‐resolution X‐ray diffraction and transmission electron microscopy. Semi‐metallic ErAs is inserted to the Al/GaAs interface to modify the band structure and reduce the optical loss of Al without degrading the crystalline quality. The optical dielectric properties of the Al films are measured by spectroscopic ellipsometry and the optical loss (ε2) is reduced in a broad spectral region from ultraviolet (UV) to near‐infrared compared to the widely quoted Palik's values. In particular, the loss in the visible region is reduced by a factor of three, indicating the effective energy band engineering by ErAs.
Roll‐to‐Roll Production of Novel Large‐Area Piezoelectric Films for Transparent, Flexible, and Wearable Fabric Loudspeakers
Authors: Yildirim Armen , Grant Jesse C. , Song Guochenhao , Yook SungHo , Mutlu Zeynep , Peana Samuel , Dhanabal Aginiprakash , Sinha Sneh K. , Daniels Robert , Bellisario Kristen M. , Sotzing Gregory A. , Huston Davin H. , Pijanowksi Bryan C. , Rahimi Rahim , Liu Yangfan , Cakmak Mukerrem
Published: June 2020

High‐performance flexible loudspeakers have the potential to revolutionize the future of flexible/wearable electronics by providing this long‐sought function. Here, a novel method is developed to produce large‐area, flexible, and transparent piezoelectric loudspeakers, where both piezoelectric lead zirconate titanate (PZT) nanoparticles and graphene nanoplatelets (GNPs) are simultaneously aligned in the thickness direction forming dense “nanocolumn forests.” The preferential alignment of the particles not only reduces filler concentration and improves the piezoelectric performance, but also provides transparency to the film by enabling light to travel with little scattering or absorption in the thickness direction. Its potential applications, such as wearable and portable personal audio systems, along with a 9‐ft‐tall immersive walk‐through soundscape structure, are also demonstrated. The performance and the directivity of each loudspeaker are characterized through sound pressure level (SPL) versus frequency measurements over human audio spectrum (20 Hz–20 kHz) in an anechoic chamber. Furthermore, scalability of this unique roll‐to‐roll process is demonstrated on a 44‐ft‐long custom designed roll‐to‐roll (R2R) manufacturing line that can produce these six‐inch‐wide multifunctional films continuously.
Functionalized Tetrapodal Diazatriptycenes for Electrostatic Dipole Engineering in n‐Type Organic Thin Film Transistors
Authors: Rohnacher Valentina , Benneckendorf Frank S. , Münch Maybritt , Sauter Eric , Asyuda Andika , Barf Marc‐Michael , Tisserant Jean‐Nicolas , Hillebrandt Sabina , Rominger Frank , Jänsch Daniel , Freudenberg Jan , Kowalsky Wolfgang , Jaegermann Wolfram , Bunz Uwe H. F. , Pucci Annemarie , Zharnikov Michael , Müllen Klaus
Published: June 2020

A diazatriptycene‐based tetrapodal scaffold with thiol anchors enforces a nearly upright orientation of functional groups, introduced to its quinoxaline subunit, with respect to the substrate upon formation of self‐assembled monolayers (SAMs). Substitution with electron‐withdrawing fluorine and cyano as well as electron‐rich dimethylamino substituents allows tuning of the molecular dipole and, consequently, of the work function of gold over a range of 1.0 eV (from 3.9 to 4.9 eV). The properties of the SAMs are comprehensively investigated by infrared reflection absorption spectroscopy, near edge X‐ray absorption fine structure spectroscopy, and X‐ray photoelectron spectroscopy. As prototypical examples for the high potential of the presented SAMs in devices, organic thin‐film transistors are fabricated.
Clarification of the Relationship between the Magnetic and Conductive Properties of Infinite Chains in Trioxotriangulene Radical Crystals by Spin‐Projected DFT/Plane‐Wave Calculations
Authors: Tada Kohei , Kawakami Takashi , Tanaka Shingo , Okumura Mitsutaka , Yamaguchi Kizashi
Published: June 2020

Approximate spin projection method and density functional theory with plane‐wave‐based calculations are combined to uncover and clarify the relationship between the magnetism and electronic conductivity of trioxotriangulene (TOT) radical crystals. The presented scheme exhibits an exceptionally high accuracy. It is clearly different from other techniques that have been conventionally used to calculate the magnitude of the effective exchange interaction (J) and the band structure of organic radicals. This enhanced performance is explained by these facts: i) the proposed scheme allows one to estimate band structures with electronic correlation between whole molecules in the crystal, ii) no crystal cutting‐induced artifacts and errors are introduced, and iii) both spin polarization and spin contamination are treated correctly. Consequently, the discrepancy between the experimental J value and the estimated value by the scheme equals 11.1 cm−1. The scheme can be applied to the DFT‐D method, which is mostly considered for dispersion force. The collaboration allows discussions on the relationship between the magnetic and electronic properties, and the geometric structures. Moreover, it gives useful insights for the design of new functional organic materials. For example, the results of Br3‐TOT revealed by the approach better explains the previously reported but nonclarified properties of these species.
A Designed α‐GalCer Analog Promotes Considerable Th1 Cytokine Response by Activating the CD1d‐iNKT Axis and CD11b‐Positive Monocytes/Macrophages
Authors: Ma Juan , He Peng , Zhao Chuanfang , Ren Quanzhong , Dong Zheng , Qiu Jiahuang , Jing Yang , Liu Sijin , Du Yuguo
Published: June 2020

Selective helper T cell 1 (Th1) priming agonists are a promising area of investigation for immunotherapeutic treatment of various diseases. α‐galactosylceramide (α‐GalCer, KRN7000), a well‐studied Th1‐polarizer, simultaneously induces helper T cell 2 (Th2)‐type responses, which is a major drawback for its clinical applications. Based on surflex‐docking computation, α‐GalCer‐diol, with added hydroxyl groups in the acyl chain, is designed and synthesized. Structural analyses reveal stronger affinity between α‐GalCer‐diol and cluster of differentiation 1d (CD1d), leading to enhanced antigen presentation by dendritic cells (DCs) and self‐activation, as reflected by tight binding of the T‐cell receptor (TCR)/KRN7000/CD1d ternary complex and elevated production of interleukin 12 (IL‐12) and interferon‐γ (IFN‐γ). Consequently, invariant natural killer T cells (iNKTs) are activated and exhibit an improved Th1‐type cytokine profile ex vivo and in vivo. Different from KRN7000, α‐GalCer‐diol markedly boosts the expansion of the CD11b+ subpopulation and enhances IFN‐γ content in CD11b+ cells. These reinforced Th1‐type responses collectively endow α‐GalCer‐diol more robust antitumor activity in a xenograft animal model using B16‐F10 melanoma cells. Together, the data demonstrate a new mechanism through which α‐GalCer‐diol induces stronger Th1‐type responses by stimulating CD11b+ leukocyte expansion and DC‐conducted CD1d‐restricted and TCR‐mediated iNKT activation. Hence, this study may facilitate the development of novel Th1 priming agonists.
The Role of Tricellulin in Epithelial Jamming and Unjamming via Segmentation of Tricellular Junctions
Authors: Lohmann Sophie , Giampietro Costanza , Pramotton Francesca M. , Al‐Nuaimi Dunja , Poli Alessandro , Maiuri Paolo , Poulikakos Dimos , Ferrari Aldo
Published: June 2020

Collective cellular behavior in confluent monolayers supports physiological and pathological processes of epithelial development, regeneration, and carcinogenesis. Here, the attainment of a mature and static tissue configuration or the local reactivation of cell motility involve a dynamic regulation of the junctions established between neighboring cells. Tricellular junctions (tTJs), established at vertexes where three cells meet, are ideally located to control cellular shape and coordinate multicellular movements. However, their function in epithelial tissue dynamic remains poorly defined. To investigate the role of tTJs establishment and maturation in the jamming and unjamming transitions of epithelial monolayers, a semi‐automatic image‐processing pipeline is developed and validated enabling the unbiased and spatially resolved determination of the tTJ maturity state based on the localization of fluorescent reporters. The software resolves the variation of tTJ maturity accompanying collective transitions during tissue maturation, wound healing, and upon the adaptation to osmolarity changes. Altogether, this work establishes junctional maturity at tricellular contacts as a novel biological descriptor of collective responses in epithelial monolayers.
Methanol as Hydrogen Source: Transfer Hydrogenation of Aldehydes near Room Temperature
Authors: Chen Zhenyu , Chen Guanhong , Aboo Ahmed H. , Iggo Jonathan , Xiao Jianliang
Published: June 2020

A cyclometalated rhodium complex has been found to show excellent activity in dehydrogenation of methanol at room temperature. This feature allows for the catalytic transfer hydrogenation of various aldehydes with methanol as both hydrogen source and solvent under very mild conditions. A hydroxy functionality on the ligand is shown to be critical for this unusual activity.
Dielectric Chiral Metasurfaces for Second‐Harmonic Generation with Strong Circular Dichroism
Authors: Kim Kwang‐Hyon , Kim Ju‐Ryong
Published: June 2020

Dielectric chiral metasurfaces can generate harmonic waves with high efficiency and strong circular dichroism (CD), when they are supported by metallic substrates. Numerical results show that the second‐harmonic generation (SHG) efficiency of about 10−3% for a peak pump intensity of about 5 GW cm−2 can be achieved in the blue‐UV, and the SHG CD reaches up to about 1.8, from a metasurface of Z‐shaped lithium niobate nanoantenna array supported by gold substrate. Highly efficient and strong circular dichroic nonlinear responses are attributed to the plasmon‐assisted local field enhancement in the dielectric chiral nanoantennae adjacent to the metallic substrate.
Quantendefekte als Werkzeugkasten für die kovalente Funktionalisierung von Kohlenstoffnanoröhren mit Peptiden und Proteinen
Authors: Mann Florian A. , Herrmann Niklas , Opazo Felipe , Kruss Sebastian
Published: June 2020

Einwandige Kohlenstoffnanoröhren (SWCNTs) sind ein 1D‐Nanomaterial, das im nahen Infrarot (NIR, >800 nm) fluoresziert. In der Vergangenheit wurde kovalente Chemie zur Funktionalisierung von SWCNTs wenig genutzt, da sie die NIR‐Emission beeinträchtigt. Es sind jedoch bestimmte sp3‐Defekte (Quantendefekte) im Kohlenstoffgitter beobachtet worden, die die NIR‐Fluoreszenz erhalten und sogar zu einer neuen, rotverschobenen Emission führen. Hier berichten wir über Quantendefekte, die mittels lichtinduzierter Diazoniumchemie eingeführt wurden und als Ankerpunkte für Peptide und Proteine dienen. Wir zeigen, dass Maleimid‐Anker die Konjugation Cystein‐haltiger Proteine, z. B. eines GFP‐bindenden Nanobodys, ermöglichen. Darüber hinaus fungiert ein Fmoc‐geschützter Phenylalanin‐Defekt als Ausgangspunkt für die Konjugation von sichtbaren Fluorophoren zur Erzeugung mehrfarbiger SWCNTs und In‐situ‐Peptidsynthese direkt auf dem Nanoröhren. Daher stellen diese Quantendefekte eine vielseitige Plattform dar, um sowohl die photophysikalischen Eigenschaften der Nanoröhren als auch ihre Oberflächenchemie anzupassen.
Crystalline Red Phosphorus Nanoribbons: Large‐Scale Synthesis and Electrochemical Nitrogen Fixation
Authors: Liu Qian , Zhang Xue , Wang Jiahong , Zhang Yanli , Bian Shi , Cheng Ziqiang , Kang Ning , Huang Hao , Gu Shuang , Wang Yun , Liu Danni , Chu Paul K. , Yu Xue‐Feng
Published: June 2020

Two dimensional (2D) nanoribbons constitute an emerging nanoarchitecture for advanced microelectronics and energy conversion due to the stronger size confinement effects compared to traditional nanosheets. Triclinic crystalline red phosphorus (cRP) composed by a layered structure is a promising 2D phosphorus allotrope and the tube‐like substructure is beneficial to the construction of nanoribbons. In this work, few‐layer cRP nanoribbons are synthesized and the effectiveness in the electrochemical nitrogen reduction reaction (NRR) is investigated. An iodine‐assisted chemical vapor transport (CVT) method is developed to synthesize circa 10 g of bulk cRP lumps with a yield of over 99 %. With the aid of probe ultrasonic treatment, high‐quality cRP microcrystals are exfoliated into few‐layer nanoribbons (cRP NRs) with large aspect ratios. As non‐metallic materials, cRP NRs are suitable for the electrochemical nitrogen reduction reaction. The ammonia yield is 15.4 μg h−1 mgcat.−1 at −0.4 V vs. reversible hydrogen electrode in a neutral electrolyte under ambient conditions and the Faradaic efficiency is 9.4 % at −0.2 V. Not only is cRP a promising catalyst, but also the novel strategy expands the application of phosphorus‐based 2D structures beyond that of traditional nanosheets.
Transition‐Metal Catalysis of Triene 6π Electrocyclization: The π‐Complexation Strategy Realized
Authors: Qin Pengjin , Wang Li‐An , O'Connor Joseph M. , Baldridge Kim K. , Li Yifan , Tufekci Burak , Chen Jiyue , Rheingold Arnold L.
Published: June 2020

Triene 6π electrocyclization, wherein a conjugated triene undergoes a concerted stereospecific cycloisomerization to a cyclohexadiene, is a reaction of great historical and practical significance. In order to circumvent limitations imposed by the normally harsh reaction conditions, chemists have long sought to develop catalytic variants based upon the activating power of metal–alkene coordination. Herein, we demonstrate the first successful implementation of such a strategy by utilizing [(C5H5)Ru(NCMe)3]PF6 as a precatalyst for the disrotatory 6π electrocyclization of highly substituted trienes that are resistant to thermal cyclization. Mechanistic and computational studies implicate hexahapto transition‐metal coordination as responsible for lowering the energetic barrier to ring closure. This work establishes a foundation for the development of new catalysts for stereoselective electrocyclizations.
Induced Fitting and Polarization of a Bromine Molecule in an Electrophilic Inorganic Molecular Cavity and Its Bromination Reactivity
Authors: Kikukawa Yuji , Seto Kensuke , Watanabe Daiki , Kitajima Hiromasa , Katayama Misaki , Yamashita Shohei , Inada Yasuhiro , Hayashi Yoshihito
Published: June 2020

Dodecavanadate, [V12O32]4− (V12), possesses a 4.4 Å cavity entrance, and the cavity shows unique electrophilicity. Owing to the high polarizability, Br2 was inserted into V12, inducing the inversion of one of the VO5 square pyramids to form [V12O32(Br2)]4− (V12(Br2)). The inserted Br2 molecule was polarized and showed a peak at 185 cm−1 in the IR spectrum. The reaction of V12(Br2) and toluene yielded bromination of toluene at the ring, showing the electrophilicity of the inserted Br2 molecule. Compound V12(Br2) also reacted with propane, n‐butane, and n‐pentane to give brominated alkanes. Bromination with V12(Br2) showed high selectivity for 3‐bromopentane (64 %) among the monobromopentane products and preferred threo isomer among 2‐,3‐dibromobutane and 2,3‐dibromopenane. The unique inorganic cavity traps Br2 leading the polarization of the diatomic molecule. Owing to its new reaction field, the trapped Br2 shows selective functionalization of alkanes.
Quantum Defects as a Toolbox for the Covalent Functionalization of Carbon Nanotubes with Peptides and Proteins
Authors: Mann Florian A. , Herrmann Niklas , Opazo Felipe , Kruss Sebastian
Published: June 2020

Single‐walled carbon nanotubes (SWCNTs) are a 1D nanomaterial that shows fluorescence in the near‐infrared (NIR, >800 nm). In the past, covalent chemistry was less explored to functionalize SWCNTs as it impairs NIR emission. However, certain sp3defects (quantum defects) in the carbon lattice have emerged that preserve NIR fluorescence and even introduce a new, red‐shifted emission peak. Here, we report on quantum defects, introduced using light‐driven diazonium chemistry, that serve as anchor points for peptides and proteins. We show that maleimide anchors allow conjugation of cysteine‐containing proteins such as a GFP‐binding nanobody. In addition, an Fmoc‐protected phenylalanine defect serves as a starting point for conjugation of visible fluorophores to create multicolor SWCNTs and in situ peptide synthesis directly on the nanotube. Therefore, these quantum defects are a versatile platform to tailor both the nanotube's photophysical properties as well as their surface chemistry.
Unilaterally Fluorinated Acenes: Synthesis and Solid‐State Properties
Authors: Hofmann Philipp E. , Tripp Matthias W. , Bischof Daniel , Grell Yvonne , Schiller Anna L. C. , Breuer Tobias , Ivlev Sergei I. , Witte Gregor , Koert Ulrich
Published: June 2020

The rapid development of organic electronics is closely related to the availability of molecular materials with specific electronic properties. Here, we introduce a novel synthetic route enabling a unilateral functionalization of acenes along their long side, which is demonstrated by the synthesis of 1,2,10,11,12,14‐hexafluoropentacene (1) and the related 1,2,9,10,11‐pentafluorotetracene (2). Quantum chemical DFT calculations in combination with optical and X‐ray absorption spectroscopy data indicate that the single‐molecule properties of 1 are a connecting link between the organic semiconductor model systems pentacene (PEN) and perfluoropentacene (PFP). In contrast, the crystal structure analysis reveals a different packing motif than for the parent molecules. This can be related to distinct F⋅⋅⋅H interactions identified in the corresponding Hirshfeld surface analysis and also affects solid‐state properties such as the exciton binding energy and the sublimation enthalpy.
Dinickelaferrocene: A Ferrocene Analogue with Two Aromatic Nickeloles Realized by Electron Back‐Donation from Iron
Authors: Huang Zhe , Zheng Yu , Zhang Wen‐Xiong , Ye Shengfa , Deng Liang , Xi Zhenfeng
Published: June 2020

The first example of ferrocene analogues with two transition‐metal metallole ligands of the general formula (η5‐C4R4M)2Fe in a sandwich structure are reported. Specifically, dinickelaferrocene 2, a type of dimetallametallocene, is efficiently synthesized from the reaction of dilithionickelole 1 with FeBr2 or FeCl2, presumably via a redox process, and is subjected to detailed experimental (single‐crystal X‐ray structural analysis, ICP‐OES, magnetometry, 57Fe Mössbauer, XPS) and theoretical (MOs, CDA, NICS, ICSS, and AICD) characterizations. Unlike ferrocene and its Cp ligands, the aromaticity of dinickelaferrocene and its nickelole ligands is accomplished by electron back‐donation from the Fe 3d orbitals to the π* orbitals of nickelole. Taken together, this work describes a new class of metallaferrocene sandwich complexes and provides a novel approach to effect aromaticity that will contribute to further development of metallocene chemistry.
The Mechanism of the Magnetodielectric Response in a Molecule‐Based Trinuclear Iron Cluster Material
Authors: Li Dong , Wang Xuan , Zhao Hai‐Xia , Ren Yan‐Ping , Zhuang Gui‐Lin , Long La‐Sheng , Zheng Lan‐Sun
Published: June 2020

Magnetodielectric response mechanisms are critical for the rational design and synthesis of molecule‐based magnetodielectric materials. Herein, the magnetodielectric response was investigated in the molecule‐based material [Fe3O(CH3COO)6(py)3](py) (1). Its magnetodielectric coefficient (MD) is −2.8 % for phase transition III and −4.1 % for phase transition I. Study of the mechanism of the magnetodielectric response in 1 reveals that its magnetodielectric response at phase transition I is induced by the charge‐frustration of the trinuclear iron cluster, while that at phase transition III is attributed to the spin‐frustration of the trinuclear iron cluster, providing a new route for the design of magnetodielectric materials.
Development of a new catalytic and sustainable methodology for the synthesis of benzodiazepine triazole scaffold using magnetically separable CuFe2O4@MIL‐101(Cr) nano‐catalyst in aqueous medium
Authors: Gupta Ajay , Sarkar Fillip Kumar , Sarkar Rajib , Jamatia Ramen , Lee Chang Yeon , Gupta Gajendra , Pal Amarta Kumar
Published: June 2020

Magnetically retrieval CuFe2O4@MIL‐101(Cr) metal–organic framework was successfully prepared from easily available starting materials and characterized using various spectroscopic and analytical techniques such as powder X‐ray diffraction, scanning electron microscopy, energy dispersive X‐ray, transmission electron microscopy, elemental mapping, Fourier transform infrared spectroscopy, thermogravimetric analysis, X‐ray photoelectron spectroscopy, Brunauer–Emmett–Teller, vibrating sample magnetometer, and inductively coupled plasma optical emission spectroscopy. The catalyst was then used in the synthesis of benzodiazepines containing a triazole moiety in water. The advantages of this protocol include high yields, reusability of the catalyst, and gram‐scale synthesis.
A green and chemoselective synthesis of coumarins via Pechmann condensation using recoverable heterogeneous catalyst (Au@pSiO2)
Authors: Yaghoobi Mandana , Zareyee Daryoush , Khalilzadeh Mohammad A.
Published: June 2020

Nano Au@porous SiO2 as a heterogeneous catalyst was prepared and characterized by Fourier transform infrared, X‐ray powder diffraction, transmission electron microscopy, thermogravimetric analysis and inductively coupled plasma–atomic emission spectroscopy techniques and then used as an efficient catalyst in the condensation of various phenols with ethyl acetoacetate for the preparation of coumarin derivatives through the Pechmann reaction. The combined merits of chemoselective and solvent free reaction conditions and the recyclability of the nanostructured catalyst make the condensation a safe operation, with low pollution, rapid access to products and simple workup.
Feasibility of lime‐modified carbonate soil for highway subgrade filling
Authors: Zheng Yuxin , Li Chunyan , Ma Qingqing
Published: June 2020

For the lime modified carbonate rock soil road subgrade of port highway, after the lime modified carbonate rock filler is used to treat it, the particle discrete unit has the characteristics of sparsity, and the particle gradation is caused by the seepage of soil mass, and with the increase in load, overload load occurs. It is therefore necessary to establish relevant mathematical models to analyze the load variation of lime‐modified carbonate roadbed under boundary conditions. The probability mathematical model of the load overload of lime‐modified carbonate fill was studied, and a feasibility analysis model of lime‐modified carbonate soil used in port city highway subgrade filling was put forward based on the discrete hysteretic characteristic curve method. The load characteristics of lime‐modified carbonate soil were analyzed within the limited area distribution range of adjacent two holes. The load energy transfer model of lime‐modified carbonate packing in foundation soil was analyzed in PFC3D software. The foundation stress reinforcement method was used to improve the carbonate soil foundation construction and, combined with the seepage model of the radial consolidation of the foundation, a filling feasibility analysis of the urban highway subgrade of lime‐modified carbonate soil port was carried out. The simulation results show that this method can effectively realize the load overload analysis of lime‐modified carbonate packing, improve the load capacity of subgrade filler for port city highway, and improve the load property of highway subgrade of port city. Keep the soil particles in close contact. This study provides a feasible basis for future highway construction and the application of lime‐modified carbonate.
A correlation between morphology and mechanical performance of injected‐molded PE/EVA/clay nanocomposites: Insight into phase miscibility and interfacial phenomena
Authors: Hosseiny Seyed Majid , Jafari Seyed Hassan , Khonakdar Hossein Ali , Hemmati Farkhondeh , Kalaee Mohammad Reza
Published: June 2020

In this study, the correlations between the mechanical performance and structural properties of injected‐molded polyethylene (PE)/ethylene‐vinyl acetate copolymer (EVA)/nanoclay (NC) nanocomposites are investigated by revisiting the interfacial phenomena and miscibility state of the component pairs. The effects of different parameters including the injection molding temperature, mixing sequence in melt‐compounding process, blend composition, and nanoclay loading are studied. A great complexity arises in the filling and cooling process of the injected‐molded parts owing to the phase behavior of the polyolefin blend, crystallization, and morphological changes. The injection molding temperature positively influences the elastic modulus, tensile strength and impact strength of PE/EVA/NC systems through the improvements in the PE/EVA partial miscibility, mutual solubility, and interfacial interactions of PE/clay and PE/EVA pairs. By applying a two‐step mixing process before the injection molding, more nanoclay stacks with smaller thicknesses and larger clay interlayer spacing are formed. The stronger pinning effect of nanoparticles in the second mixing sequence retards the phase separation phenomenon of PE/EVA blend during the cooling stage. As a result of improved mutual PE/EVA solubility, the elastic modulus and tensile strength decrease and the impact resistance increases in the PE‐rich systems. On the other hand, an opposite trend for these properties is found for the EVA‐rich systems.