bluuebunny/crossref_metadata_2025 huggingface dataset:
Haze in Singapore – source attribution of biomass burning PM10 from Southeast Asia
Authors: Hansen Ayoe Buus , Witham Claire Suzanne , Chong Wei Ming , Kendall Emma , Chew Boon Ning , Gan Christopher , Hort Matthew Craig , Lee Shao-Yi
Published: April 2019

Abstract. This paper presents a study of haze in Singapore
caused by biomass burning in Southeast Asia over the 6-year period from 2010
to 2015, using the Numerical Atmospheric-dispersion Modelling Environment
(NAME), which is a Lagrangian dispersion model. The major contributing source
regions to the haze are identified using forwards and backwards model
simulations of particulate matter. The coincidence of relatively strong southeast monsoonal winds with increased
biomass burning activities in the Maritime Continent create the main
Singapore haze season from August to October (ASO), which brings particulate
matter from varying source regions to Singapore. Five regions are identified
as the dominating sources of pollution during recent haze seasons: Riau,
Peninsular Malaysia, South Sumatra, and Central and West Kalimantan. In
contrast, off-season haze episodes in Singapore are characterised by unusual
weather conditions, ideal for biomass burning, and contributions dominated by
a single source region (different for each event). The two most recent
off-season haze events in mid-2013 and early 2014 have different source
regions, which differ from the major contributing source regions for the haze
season. These results challenge the current popular assumption that haze in
Singapore is dominated by emissions/burning from only Indonesia. For example,
it is shown that Peninsular Malaysia is a large source for the Maritime
Continent off-season biomass burning impact on Singapore. The results demonstrate that haze in Singapore varies across year, season,
and location and is influenced by local and regional weather, climate, and
regional burning. Differences in haze concentrations and variation in the
relative contributions from the various source regions are seen between
monitoring stations across Singapore, on a seasonal as well as on an
inter-annual timescale. This study shows that even across small scales, such
as in Singapore, variation in local meteorology can impact concentrations of
particulate matter significantly, and it emphasises the importance of the scale
of modelling both spatially and temporally.
Aerosol-type classification based on AERONET version 3 inversion products
Authors: Shin Sung-Kyun , Tesche Matthias , Noh Youngmin , Müller Detlef
Published: April 2019

Abstract. This study proposes an aerosol-type classification based on the particle linear depolarization ratio (PLDR) and single scattering albedo (SSA) provided in the AErosol RObotic NETwork (AERONET) version 3 level 2.0 inversion product. We compare our aerosol-type classification with an earlier method that uses fine-mode fraction (FMF) and SSA. Our new method allows for a refined classification of mineral dust that occurs as a mixture with other absorbing aerosols: pure dust (PD), dust-dominated mixed plume (DDM), and pollutant-dominated mixed plume (PDM). We test the aerosol classification at AERONET sites in East Asia that are frequently affected by mixtures of Asian dust and biomass-burning smoke or anthropogenic pollution. We find that East Asia is strongly affected by pollution particles with high occurrence frequencies of 50 % to 67 %. The distribution and types of pollution particles vary with location and season. The frequency of PD and dusty aerosol mixture (DDM+PDM) is slightly lower (34 % to 49 %) than pollution-dominated mixtures. Pure dust particles have been detected in only 1 % of observations. This suggests that East Asian dust plumes generally exist in a mixture with pollution aerosols rather than in pure form. In this study, we have also considered data from selected AERONET sites that are representative of anthropogenic pollution, biomass-burning smoke, and mineral dust. We find that average aerosol properties obtained for aerosol types in our PLDR-SSA-based classification agree reasonably well with those obtained at AERONET sites representative for different aerosol types.
Scalable diagnostics for global atmospheric chemistry using Ristretto library (version 1.0)
Authors: Velegar Meghana , Erichson N. Benjamin , Keller Christoph A. , Kutz J. Nathan
Published: April 2019

Abstract. We introduce a new set of algorithmic tools capable of producing scalable,
low-rank decompositions of global spatiotemporal atmospheric chemistry data.
By exploiting emerging randomized linear algebra algorithms, a suite
of decompositions are proposed that extract the dominant features from
big data sets (i.e., global atmospheric chemistry at longitude,
latitude, and elevation) with improved interpretability. Importantly, our
proposed algorithms scale with the intrinsic rank of the global chemistry
space rather than the ever increasing spatiotemporal measurement space, thus
allowing for the efficient representation and compression of the data. In
addition to scalability, two additional innovations are proposed for improved
interpretability: (i) a nonnegative decomposition of the data for improved
interpretability by constraining the chemical space to have only positive
expression values (unlike PCA analysis); and (ii) sparse matrix
decompositions, which threshold small weights to zero, thus highlighting the
dominant, localized spatial activity (again unlike PCA analysis). Our methods
are demonstrated on a full year of global chemistry dynamics data, showing
the significant improvement in computational speed and interpretability. We
show that the decomposition methods presented here successfully extract known
major features of atmospheric chemistry, such as summertime surface pollution
and biomass burning activities.
The [simple carbon project] model v1.0
Authors: O'Neill Cameron M. , Hogg Andrew McC. , Ellwood Michael J. , Eggins Stephen M. , Opdyke Bradley N.
Published: April 2019

Abstract. We construct a carbon cycle box model to process observed or inferred
geochemical evidence from modern and paleo settings. The [simple carbon
project] model v1.0 (SCP-M) combines a modern understanding of the ocean
circulation regime with the Earth's carbon cycle. SCP-M estimates the
concentrations of a range of elements within the carbon cycle by simulating
ocean circulation, biological, chemical, atmospheric and terrestrial
carbon cycle processes. The model is capable of reproducing both paleo and
modern observations and aligns with CMIP5 model projections. SCP-M's fast
run time, simplified layout and matrix structure render it a flexible and
easy-to-use tool for paleo and modern carbon cycle simulations. The ease of
data integration also enables model–data optimisations. Limitations of the
model include the prescription of many fluxes and an ocean-basin-averaged
topology, which may not be applicable to more detailed simulations. In this paper we demonstrate SCP-M's application primarily with an analysis of
the carbon cycle transition from the Last Glacial Maximum (LGM) to the Holocene and also
with the modern carbon cycle under the influence of anthropogenic CO2
emissions. We conduct an atmospheric and ocean multi-proxy model–data
parameter optimisation for the LGM and late Holocene periods using the
growing pool of published paleo atmosphere and ocean data for CO2,
δ13C, Δ14C and the carbonate ion proxy. The results
provide strong evidence for an ocean-wide physical mechanism to deliver the
LGM-to-Holocene carbon cycle transition. Alongside ancillary changes in ocean
temperature, volume, salinity, sea-ice cover and atmospheric radiocarbon
production rate, changes in global overturning circulation and, to a lesser
extent, Atlantic meridional overturning circulation can drive the observed
LGM and late Holocene signals in atmospheric CO2, δ13C,
Δ14C, and the oceanic distribution of δ13C,
Δ14C and the carbonate ion proxy. Further work is needed on the analysis
and processing of ocean proxy data to improve confidence in these
modelling results.
Influence of multi-decadal land use, irrigation practices and climate on riparian corridors across the Upper Missouri River Headwaters Basin, Montana
Authors: Vanderhoof Melanie K. , Christensen Jay R. , Alexander Laurie C.
Published: April 2019

Abstract. The Upper Missouri River Headwaters Basin (36 400 km2) depends on its river corridors to support irrigated agriculture and world-class trout fisheries. We evaluated trends (1984–2016) in riparian wetness, an indicator of riparian condition, in peak irrigation months (June, July, August) for 158 km2 of riparian area across the basin using the Landsat Normalized Difference Wetness Index (NDWI). We found that 8 of the 19 riparian reaches across the basin showed a significant drying trend over this period, including all three basin outlet reaches along the Jefferson, Madison and Gallatin Rivers. The influence of upstream climate was quantified using per reach random forest regressions. Although much of the interannual variability was explained by climate, especially by drought indices and annual precipitation, the significant drying trends persisted in the NDWI-climate model residuals, indicating that trends were not entirely attributable to climate. Over the same period we documented a 506 % increase in center-pivot irrigation and an associated 39 % decrease in non-center pivot irrigation basin-wide. Riparian reaches with a drying trend had a greater shift towards center-pivot irrigation relative to riparian reaches without such a trend (p
EVALUATION OF VISION-BASED LOCALIZATION AND MAPPING TECHNIQUES IN A SUBSEA METROLOGY SCENARIO
Authors: Menna F. , Torresani A. , Nocerino E. , Nawaf M. M. , Seinturier J. , Remondino F. , Drap P. , Chemisky B.
Published: April 2019

Abstract. Metrology is fundamental in all the applications that require to qualify, verify and validate measured data according to standards or, in other words, to assess their compliance with predefined tolerances. At sea, metrology is commonly associated with the process of measuring underwater structures, mainly pipeline elements widely used in offshore industry. Subsea operations are very expensive; optimizing time and money resources are the core factors driving innovation in the subsea metrology industry. In this study, the authors investigate the use of state-of-art vision-based algorithms, i.e. ORB-SLAM2 and Visual Odometry, as a navigation tool to assist and control a Remotely Operated Vehicle (ROV) while performing subsea metrology operations. In particular, the manuscript will focus on methods for assessing the accuracy of both trajectory and tie points provided by the tested approaches and evaluating whether the preliminary real time reconstruction meets the tolerances defined in typical subsea metrology scenarios.
SEMANTIC SEGMENTATION OF BENTHIC COMMUNITIES FROM ORTHO-MOSAIC MAPS
Authors: Pavoni G. , Corsini M. , Callieri M. , Palma M. , Scopigno R.
Published: April 2019

Abstract. Visual sampling techniques represent a valuable resource for a rapid, non-invasive data acquisition for underwater monitoring purposes. Long-term monitoring projects usually requires the collection of large quantities of data, and the visual analysis of a human expert operator remains, in this context, a very time consuming task. It has been estimated that only the 1-2% of the acquired images are later analyzed by scientists (Beijbom et al., 2012). Strategies for the automatic recognition of benthic communities are required to effectively exploit all the information contained in visual data. Supervised learning methods, the most promising classification techniques in this field, are commonly affected by two recurring issues: the wide diversity of marine organism, and the small amount of labeled data. In this work, we discuss the advantages offered by the use of annotated high resolution ortho-mosaics of seabed to classify and segment the investigated specimens, and we suggest several strategies to obtain a considerable per-pixel classification performance although the use of a reduced training dataset composed by a single ortho-mosaic. The proposed methodology can be applied to a large number of different species, making the procedure of marine organism identification an highly adaptable task.
UNDERSTANDING UNDERWATER PHOTOGRAMMETRY FOR MARITIME ARCHAEOLOGY THROUGH IMMERSIVE VIRTUAL REALITY
Authors: Doležal M. , Vlachos M. , Secci M. , Demesticha S. , Skarlatos D. , Liarokapis F.
Published: April 2019

Abstract. Underwater archaeological discoveries bring new challenges to the field, but such sites are more difficult to reach and, due to natural influences, they tend to deteriorate fast. Photogrammetry is one of the most powerful tools used for archaeological fieldwork. Photogrammetric techniques are used to document the state of the site in digital form for later analysis, without the risk of damaging any of the artefacts or the site itself. To achieve best possible results with the gathered data, divers should come prepared with the knowledge of measurements and photo capture methods. Archaeologists use this technology to record discovered arteacts or even the whole archaeological sites. Data gathering underwater brings several problems and limitations, so specific steps should be taken to get the best possible results, and divers should well be prepared before starting work at an underwater site. Using immersive virtual reality, we have developed an educational software to introduce maritime archaeology students to photogrammetry techniques. To test the feasibility of the software, a user study was performed and evaluated by experts. In the software, the user is tasked to put markers on the site, measure distances between them, and then take photos of the site, from which the 3D mesh is generated offline. Initial results show that the system is useful for understanding the basics of underwater photogrammetry.
Periprosthetic Infections of the Shoulder: Diagnosis and Management
Authors: Paxton E. Scott , Green Andrew , Krueger Van S.
Published: April 2019

The use of shoulder arthroplasty is continuing to expand. Periprosthetic joint infection of the shoulder is a devastating complication occurring in approximately 1% of cases. The most common organisms responsible for the infection are Cutibacterium acnes (formerly Propionibacterium acnes) (∼39%) and coagulase-negative Staphylococcus (∼29%). Evaluation of patients includes history and physical examination, serologic testing, imaging, possible joint aspiration, and tissue culture. Diagnosing infections caused by lower virulence organisms (eg, C acnes) poses a challenge to the surgeon because traditional diagnostic tests (erythrocyte sedimentation rate, C-reactive protein, and joint aspiration) have a low sensitivity due to the lack of an inflammatory response. Periprosthetic joint infections of the shoulder due to Staphylococcus aureus and other highly virulent organisms are often easy to diagnose and are usually treated with two-stage revisions. However, for infections with C acnes and coagulase-negative Staphylococcus, single- and two-stage revision surgeries have shown similar ability to clear the infection. Unexpected positive cultures for C acnes during revision surgery are not uncommon; the proper management is still under investigation and remains a challenge.
Diagnostyka numeryczna powstawania i struktury strumienia kumulacyjnego z wkładki napędzanej produktami detonacji
Authors: Bagrowski Jan , Borkowski Jacek , Podgórzak Paweł , Jach Karol
Published: April 2019

W artykule zaprezentowano zbadane procesy zbiegania się elementów stożkowej wkładki kumulacyjnej do osi symetrii i podziału na części wewnętrzną wchodzącą do strumienia i zewnętrzną pozostającą w zbitku. Element wkładki miał długość komórki numerycznej i był podzielony na 18 warstw prostopadle do tworzącej wkładki. Pokazano występowanie gradientów prędkości wzdłuż części elementów wkładki tworzących strumień – pierwsze wewnętrzne warstwy elementów wkładki uzyskują maksymalne prędkości. W konsekwencji strumień kumulacyjny ma strukturę warstwo-wą, podobnie jak strumień powstający podczas kumulacji wkładek półsferycznych. Jednorodność osiowa strumienia jest funkcją ziarnistości materiału wkładki, w naszym przypadku rozmiarów komórek numerycznych. Wyniki rozwiązań numerycznych zostały porównane z wynikami obliczeń metodą analityczną opartą na modelu PER.
A novel class of inferior colliculus principal neurons labeled in vasoactive intestinal peptide-Cre mice
Authors: Goyer David , Silveira Marina A , George Alexander P , Beebe Nichole L , Edelbrock Ryan M , Malinski Peter T , Schofield Brett R , Roberts Michael T
Published: April 2019

Located in the midbrain, the inferior colliculus (IC) is the hub of the central auditory system. Although the IC plays important roles in speech processing, sound localization, and other auditory computations, the organization of the IC microcircuitry remains largely unknown. Using a multifaceted approach in mice, we have identified vasoactive intestinal peptide (VIP) neurons as a novel class of IC principal neurons. VIP neurons are glutamatergic stellate cells with sustained firing patterns. Their extensive axons project to long-range targets including the auditory thalamus, auditory brainstem, superior colliculus, and periaqueductal gray. Using optogenetic circuit mapping, we found that VIP neurons integrate input from the contralateral IC and the dorsal cochlear nucleus. The dorsal cochlear nucleus also drove feedforward inhibition to VIP neurons, indicating that inhibitory circuits within the IC shape the temporal integration of ascending inputs. Thus, VIP neurons are well-positioned to influence auditory computations in a number of brain regions.
Impact of Infection Prevention and Control Education Program on Improving Knowledge, Attitude and Practices of the Healthcare Staff in Hemodialysis Unit at Egyptian Tertiary Care Facility
Authors: Abdelwahab Marwa Ahmed , Labah Eman Abdel Raheem , Sayed Laila Mahmoud , Elbedwey Mohamed Mokhtar , Gabr Heba Mohamed
Published: April 2019

Objective: Infection is a leading cause of hospitalization and the second most common cause of mortality among hemodialysis (HD) patients. The aim of this study is to assess the impact of infection prevention and control education program on improving healthcare workers knowledge, attitude and practices and reducing incidence of infection in the hemodialysis unit.

Methodology: All patients and healthcare workers in the unit within the study period were included. This study was conducted through 3 phases; Phase I: base line survey for assessment of infection prevention and control knowledge, attitude and practices among healthcare workers, Phase II: Intervention that included infection control standardized education program followed by post education survey. Phase III: Implementation of infection control program was done associated with assessment of blood born viruses (HCV, HBV & HIV) and monitoring patients for fever and/or local signs of inflammation at catheter exit or at skin around shunt to be subjected to blood culture.

Results: Health care workers knowledge, attitude and practices of infection prevention and control before intervention were unsatisfactory followed by significant improvement reflecting the effectiveness of such interventions. Regarding incidence of infection there were three cases of blood stream infections; two of them were multidrug resistant organisms (MDROs) and no reported cases of seroconverion for HIV, HCV or HBV during study period. 

Conclusion: Lack of knowledge about infection prevention and control practices in hemodialysis unit could be significantly improved by standardized education program which results in reducing incidence of infections in such units.
Impact of treatment planning using a structure block function on the target and organ doses related to patient movement in cervical esophageal cancer: A phantom study
Authors: Shimizu Hidetoshi , Sasaki Koji , Ito Makoto , Aoyama Takahiro , Tachibana Hiroyuki , Tomita Natsuo , Makita Chiyoko , Tanaka Hiroshi , Koide Yutaro , Iwata Tohru , Kodaira Takeshi
Published: April 2019

Helical tomotherapy (HT) can restrict beamlets passing through the virtual contour on computed tomography (CT) image in dose optimization, reducing the dose to organs at risk (OARs). Beamlet restriction limits the incident beamlet angles; thus, the proper planning target volume (PTV) margin may differ from that of the standard treatment plan without beamlet restriction, depending on the patient's movement during dose delivery. Dose distribution changes resulting from patient movement have not been described for treatment plans with beamlet restriction. This study quantified changes in dose distribution to the target and OARs when beamlet restriction is applied to cervical esophageal cancer treatment plan using HT by systematically shifting a phantom. Treatment plans for cervical esophageal cancers with and without beamlet restriction modes [directional block (DB) and nonblock (NB), respectively] were designed for CT images of the RANDO phantom. The PTV margin for the DB mode was set to be the same as that for the NB mode (5 mm). The CT image was intentionally shifted by ±1, ±2, and ±3 voxels in the left–right, anterior–posterior, and superior–inferior directions, and the dose distribution was recalculated for each position using the fluence for the NB or DB mode. When the phantom shift was within the same PTV margin as the NB mode, changes in doses to the targets, lungs, heart, and spinal cord in the DB mode were small as those in the NB mode. In conclusion, the virtual contour shape used in this study would provide safe delivery even with patient movement within the same PTV margin as for the NB mode.
Unitized Configuration Design of Thermally Stable Composite Polymer Electrolyte for Lithium Batteries Capable of Working Over a Wide Range of Temperatures
Authors: Li Ruguang , Wu Dabei , Yu Le , Mei Yueni , Wang Libin , Li Heng , Hu Xianluo
Published: April 2019

Solid‐state electrolytes that can meet the requirements of high‐safety lithium batteries at high temperature aroused much attention in electrochemical energy storage.Nevertheless, the low ionic conductivity at ambient temperature and poor mechanical strength limit their practical applications. Through unitized configurationdesign, herein, a unique safe and flexible composite polymer electrolyte membrane comprising of inorganic ceramic particles (Li6.75La3Zr1.75Nb0.25O12, LLZNO), polyvinylidene fluoride (PVDF), and lithium perchlorate (LiClO4) are fabricated. Benefitting from the strongly coupled effects via interfacial chemical reactions and the synergistic effects between LLZNOand PVDF, the LLZNO‐based composite electrolyte wetted by ionic liquid exhibits a high ionic conductivity of 1.5 × 10−3 S cm−1 at 25 °C. Moreover, the electrolyte is able to be thermally stable at relatively high temperatures. A LiFePO4 (+) // Li (−) lithium battery using the as‐prepared LLZNO‐based composite electrolyte achieves a good electrochemical stability at ambient temperature, 80 °C and even 120 °C. This work provides an effective way to the fabrication of high‐performance, flexible electrolyte membranes for lithium batteries and other energy‐storage devices that are capable of working over a wide range of temperatures
Porphyrin Covalent Organic Framework (POF)‐Based Interface Engineering for Solar Steam Generation
Authors: Xia Zi‐Jing , Yang Hao‐Cheng , Chen Zhaowei , Waldman Ruben Z. , Zhao Yusen , Zhang Chao , Patel Shrayesh N. , Darling Seth B.
Published: April 2019

Through replacement of traditional energy sources with sunlight as the heat source, solar steam generation has emerged as a promising technology for water purification and residuals management. Despite significant efforts to develop efficient photothermal materials for solar steam devices, challenges associated with scalable fabrication of high‐performance materials remain. Moreover, most existing methods cannot be easily engineered to produce steam‐generating devices with both arbitrary control over shape and high photothermal efficiency. Herein, a flexible porphyrin organic framework (POF)‐based interface engineering method is introduced to produce high‐performance solar steam generators. POFs, a recently discovered class of materials, are demonstrated to grow readily on a diverse range of porous substrates, including membranes, fabrics, sponges, and wood. Wood@POF exhibits particularly strong performance, achieving ≈80% light‐to‐steam conversion efficiency. This study demonstrates a universal, simple, and scalable interface engineering strategy for the fabrication of solar steam generators based on POF materials.
Iodide‐Catalyzed Phosphorothiolation of Heteroarenes Using P(O)H Compounds and Elemental Sulfur
Authors: Shi Shanshan , Chen Jun , Zhuo Shaohua , Wu Zi'ang , Fang Meijuan , Tang Guo , Zhao Yufen
Published: April 2019

Organothiophosphates have found widespread application as biologically active compounds and synthetic intermediates in medicinal chemistry. The first transition‐metal‐free one‐pot direct synthesis of heterocyclic phosphorothioates involving indole or imidazo[1,2‐a]pyridine derivatives, elemental sulfur, and P(O)H compounds is presented. The use of NaI or KI as a catalyst, tert‐butyl hydroperoxide as an oxidant, various indole and imidazo[1,2‐a]pyridine derivatives are tolerant in this transformation, affording the corresponding products in good to excellent yields. Moreover, this method can be easily adapted to large‐scale preparation. O,O‐Diethyl S‐(1‐phenyl‐1H‐indol‐3‐yl) phosphorothioate presents potent anti‐inflammatory activity in lipopolysaccharide (LPS)‐stimulated RAW264.7 cells in a dose‐dependent manner.

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Amorphous Spiro‐OMeTAD Prepared Flexible Films with Surface Engineering Boost Ternary Resistive Memory Yield to 86%
Authors: Zhao Yong‐Yan , Sun Wu‐Ji , He Jing‐Hui , Lu Jian‐Mei
Published: April 2019

Organic ternary resistive memories can greatly improve the information density and thus are being extensively explored. However, the effective ternary device yield remains too low (usually <50%) for potential industrialization despite that laborious formula innovations have been attempted to improve molecular conjugation and crystallinity of the active materials. Here, it is demonstrated that using solvent and surface engineering, the devices based on amorphous 2,2′,7,7′‐tetrakis[N,N‐di(4‐methoxyphenyl) amino]‐9,9′‐spirobifluorene (Spiro‐OMeTAD) achieve a ternary device yield of 86%, which is the highest among all reported to date. Spiro‐OMeTAD is amorphous in the thin film and has a pristine device yield of 42%, challenging the concept that conjugated molecules or polymers should be employed in resistive memories. In addition, by optimizing the film thickness and surface smoothness through solvent and surface engineering, Spiro‐OMeTAD on octyl phosphonic acid‐modified indium‐tin‐oxide (ITO) glass has much smoother surface, and the ternary device yield is elevated to 86%. The amorphous nature of Spiro‐OMeTAD also enables polyethylene terephthalate‐ITO/Spiro‐OMeTAD/Al device to display outstanding flexibility with no significant decline of ternary device yield undergo 10 000 bending cycles and 72° bending degree. The result stimulates more material selections and paves the way for practical application of resistive memories.
Quantifying the Volumetric Performance Metrics of Supercapacitors
Authors: Li Huan , Qi Changsheng , Tao Ying , Liu Huabo , Wang Da‐Wei , Li Feng , Yang Quan‐Hong , Cheng Hui‐Ming
Published: April 2019

Nanostructured materials have greatly improved the performance of electrochemical energy storage devices because of the increased activity and surface area. However, nanomaterials (e.g., nanocarbons) normally possess low packing density, and thus occupy more space which restricts their suitability for making electrochemical devices as compact as possible. This has resulted in their low volumetric performance (capacitance, energy density, and power density), which is a practical obstacle for the application of nanomaterials in mobile and on‐board energy storage devices. While rating electrode materials for supercapacitors, their volumetric performance is equally important as the gravimetric metrics and more reliable in particular for systems with limited space. However, the adopted criteria for measuring the volumetric performance of supercapacitors vary in the literature. Identifying the appropriate performance criteria for the volumetric values will set a universal ground for valid comparison. Here, the authors discuss the rationale for quantifying the volumetric performance metrics of supercapacitors from the three progressive levels of materials, electrodes, and devices. It is hoped that these thoughts will be of value for the general community in energy storage research.
Activating the Violation of Steering Inequality for Two‐Qubit X States
Authors: Pan Guo‐Zhu , Yang Ming , Zhang Gang , Cao Zhuo‐Liang
Published: April 2019

The phenomenon of superactivation of quantum steering, that is, the fact that by combining several copies of the unsteerable quantum state one can get a steerable quantum state, has recently attracted much attention. This property is currently only known for isotropic states, and whether there exists an example other than isotropic states is so far an open question. It is of great importance to learn the activation property of non‐isotropic states. In this paper, it is shown that the violation of the local uncertainty relations (LUR) steering inequality can be activated for two‐qubit X type entangled mixed states. Although the activation phenomenon proven in this paper cannot guarantee the superactivation of steering for two‐qubit X states, it does provide clues for this goal. In addition, previous results indicate that two copies are enough for the superactivation of steering, while the price to pay is a high local dimension, and it is unclear whether superactivation is possible with few copies in low‐dimensional systems such as two‐qubit systems. By providing examples of activation of LUR steering inequality with two copies in a two‐qubit system, the work may open a potential way to the solution of this question.
Selenmodifizierte Mikrogele als bioinspirierte Oxidationskatalysatoren
Authors: Tan Kok H. , Xu Wenjing , Stefka Simon , Demco Dan E. , Kharandiuk Tetiana , Ivasiv Volodymyr , Nebesnyi Roman , Petrovskii Vladislav S. , Potemkin Igor I. , Pich Andrij
Published: April 2019

Anhand des Vorbilds von Glutathionperoxidase (GPx) wurden Mikrogele mit Selenfunktionalitäten versehen und somit katalytisch aktive, kolloidale Mikrogele gewonnen. Diselenid‐basierte Vernetzer (Se X‐Linker) wurden synthetisiert und gemeinsam mit dem konventionellen Vernetzer N,N′‐Methylenbis(acrylamid) (BIS) mittels Fällungspolymerisation in Mikrogele eingebracht. Die in den Mikrogelen verteilten Diselenidbrücken konnten selektiv mittels Oxidation durch H2O2 gespalten und zu Selensäure umgesetzt werden, ohne dass die Mikrogele an struktureller Integrität einbüßten. Auf diese Weise wurden katalytisch aktive Mikrogele mit variablem Selensäuregehalt synthetisiert. Beachtenswert ist, dass die so erhaltenen Mikrogele in einer Modellreaktion, der Oxidation von Acrolein zu Acrylsäure (AA) und Methacrylsäure (MA), im Vergleich zum reinen Se X‐Linker eine erhöhte katalytische Aktivität aufweisen.
C‐Terminal Bioconjugation of Peptides through Photoredox Catalyzed Decarboxylative Alkynylation
Authors: Garreau Marion , Le Vaillant Franck , Waser Jerome
Published: April 2019

We report the first decarboxylative alkynylation of the C‐terminus of peptides starting from free carboxylic acids. The reaction is fast, metal‐free, and proceeds cleanly to afford alkynylated peptides with a broad tolerance for the C‐terminal amino acid. By the use of hypervalent iodine reagents, the introduction of a broad range of functional groups was successful. C‐terminal selectivity was achieved by differentiation of the oxidation potentials of the carboxylic acids based on the use of fine‐tuned organic dyes.
Ionophore‐Based Biphasic Chemical Sensing in Droplet Microfluidics
Authors: Wang Xuewei , Sun Meng , Ferguson Stephen A. , Hoff J. Damon , Qin Yu , Bailey Ryan C. , Meyerhoff Mark E.
Published: April 2019

Droplet microfluidics is an enabling platform for high‐throughput screens, single‐cell studies, low‐volume chemical diagnostics, and microscale material syntheses. Analytical methods for real‐time and in situ detection of chemicals in the droplets will benefit these applications, but they remain limited. Reported herein is a novel heterogeneous chemical sensing strategy based on functionalization of the oil phase with rationally combined sensing reagents. Sub‐nanoliter oil segments containing pH‐sensitive fluorophores, ionophores, and ion‐exchangers enable highly selective and rapid fluorescence detection of physiologically important electrolytes (K+, Na+, and Cl−) and polyions (protamine) in sub‐nanoliter aqueous droplets. Electrolyte analysis in whole blood is demonstrated without suffering from optical interference from the sample matrix. Moreover, an oil phase doped with an aza‐BODIPY dye allows indication of H2O2 in the aqueous droplets, exemplifying sensing of targets beyond ionic species.
Copper‐Catalyzed N−F Bond Activation for Uniform Intramolecular C−H Amination Yielding Pyrrolidines and Piperidines
Authors: Bafaluy Daniel , Muñoz‐Molina José María , Funes‐Ardoiz Ignacio , Herold Sebastian , de Aguirre Adiran J. , Zhang Hongwei , Maseras Feliu , Belderrain Tomás R. , Pérez Pedro J. , Muñiz Kilian
Published: April 2019

The dual function of the N−F bond as an effective oxidant and subsequent nitrogen source in intramolecular aliphatic C−H functionalization reactions is explored. Copper catalysis is demonstrated to exercise full regio‐ and chemoselectivity control, which opens new synthetic avenues to nitrogenated heterocycles with predictable ring sizes. For the first time, a uniform catalysis manifold has been identified for the construction of both pyrrolidine and piperidine cores. The individual steps of this new copper oxidation catalysis were elucidated by control experiments and computational studies, clarifying the singularity of the N−F function and characterizing the catalytic cycle to be based on a copper(I/II) manifold.
Cross‐Peaks in Simple Two‐Dimensional NMR Experiments from Chemical Exchange of Transverse Magnetisation
Authors: Waudby Christopher A. , Frenkiel Tom , Christodoulou John
Published: April 2019

Two‐dimensional correlation measurements such as COSY, NOESY, HMQC, and HSQC experiments are central to small‐molecule and biomolecular NMR spectroscopy, and commonly form the basis of more complex experiments designed to study chemical exchange occurring during additional mixing periods. However, exchange occurring during chemical shift evolution periods can also influence the appearance of such spectra. While this is often exploited through one‐dimensional lineshape analysis (“dynamic NMR”), the analysis of exchange across multiple chemical shift evolution periods has received less attention. Here we report that chemical exchange‐induced cross‐peaks can arise in even the simplest two‐dimensional NMR experiments. These cross‐peaks can have highly distorted phases that contain rich information about the underlying exchange process. The quantitative analysis of such peaks, from a single 2D spectrum, can provide a highly accurate characterisation of underlying exchange processes.
Amylose‐grafted Curdlan: A New Class of Semi‐artificial Branched Polysaccharides for Hierarchical Polymeric Superstructures Created by the Action of “Orthogonal” Binding Sites
Authors: Tamaru Shun‐ichi , Honzaki Miyabi , Kamogawa Kinosuke , Hori Kaori , Kubo Miki , Kuroda Naofumi , Shinkai Seiji
Published: April 2019

The semi‐artificial branched‐polysaccharides, amylose‐grafted curdlans, were synthesized utilizing an enzymatic polymerization. Both a curdlan main chain and amylose side chains on the polysaccharides maintain the original helical structure as well as the molecular binding ability. Thanks to the difference in their molecular recognition properties between β‐1,3‐glucan chain and α‐1,4‐glucan chain, the amylose‐grafted curdlans can provide two different orthogonal binding sites within one polymeric system. When a water‐soluble polythiophene was mixed with the amylose‐grafted curdlan, the polythiophene was twisted in two different modes and therein, fluorescence energy of the polythiophene wrapped by the amylose side chains was successfully transferred to the polythiophene wrapped by the curdlan main chain. We thus concluded that in the dendritic superstructure of this polysaccharide, a self‐organized “Janus‐type FRET system” was successfully constructed.
The impact of shared financial decision making on overconfidence for married adults
Authors: Warmath Dee , Piehlmaier Dominik , Robb Cliff
Published: April 2019

Previous research has shown that overconfidence is associated with a decrease in the quality of decision making and, therefore, decision outcomes. However, less is known about the conditions or circumstances that reduce financial overconfidence. Using data from two national studies, this study was designed to provide insights into the dynamics of intrahousehold financial decision making by examining the role of shared decision making in reducing overconfidence bias. Findings suggest that a psychological sense of shared ownership of money is associated with lower levels of overconfidence. With regard to financial planning practice, these results suggest that married individuals who believe in shared ownership of household money tend to have lower levels of overconfidence.
Extraction of Reliable Molecular Information from Diffusion NMR Spectroscopy: Hydrodynamic Volume or Molecular Mass?
Authors: Zaccaria Francesco , Zuccaccia Cristiano , Cipullo Roberta , Macchioni Alceo
Published: April 2019

Measuring accurate translational self‐diffusion coefficients (Dt) by NMR techniques with modern spectrometers has become rather routine. In contrast, the derivation of reliable molecular information therefrom still remains a nontrivial task. In this paper, two established approaches to estimating molecular size in terms of hydrodynamic volume (VH) or molecular weight (M) are compared. Ad hoc designed experiments allowed the critical aspects of their application to be explored by translating relatively complex theoretical principles into practical take‐home messages. For instance, comparing the Dt values of three isosteric Cp2MCl2 complexes (Cp=cyclopentadienyl, M=Ti, Zr, Hf), having significantly different molecular mass, provided an empirical demonstration that VH is the critical molecular property affecting Dt. This central concept served to clarify the assumptions behind the derivation of Dt=ƒ(M) power laws from the Stokes–Einstein equation. Some pitfalls in establishing log (Dt) versus log (M) linear correlations for a set of species have been highlighted by further investigations of selected examples. The effectiveness of the Stokes–Einstein equation itself in describing the aggregation or polymerization of differently shaped species has been explored by comparing, for example, a ball‐shaped silsesquioxane cage with its cigar‐like dimeric form, or styrene with polystyrene macromolecules.
Enhancing the Viscosity‐Sensitive Range of a BODIPY Molecular Rotor by Two Orders of Magnitude
Authors: Toliautas Stepas , Dodonova Jelena , Žvirblis Audrius , Čiplys Ignas , Polita Artūras , Devižis Andrius , Tumkevičius Sigitas , Šulskus Juozas , Vyšniauskas Aurimas
Published: April 2019

Molecular rotors are a class of fluorophores that enable convenient imaging of viscosity inside microscopic samples such as lipid vesicles or live cells. Currently, rotor compounds containing a boron‐dipyrromethene (BODIPY) group are among the most promising viscosity probes. In this work, it is reported that by adding heavy‐electron‐withdrawing −NO2 groups, the viscosity‐sensitive range of a BODIPY probe is drastically expanded from 5–1500 cP to 0.5–50 000 cP. The improved range makes it, to our knowledge, the first hydrophobic molecular rotor applicable not only at moderate viscosities but also for viscosity measurements in highly viscous samples. Furthermore, the photophysical mechanism of the BODIPY molecular rotors under study has been determined by performing quantum chemical calculations and transient absorption experiments. This mechanism demonstrates how BODIPY molecular rotors work in general, why the −NO2 group causes such an improvement, and why BODIPY molecular rotors suffer from undesirable sensitivity to temperature. Overall, besides reporting a viscosity probe with remarkable properties, the results obtained expand the general understanding of molecular rotors and show a way to use the knowledge of their molecular action mechanism for augmenting their viscosity‐sensing properties.
Modelling the Inhibition of Selenoproteins by Small Molecules Using Cysteine and Selenocysteine Derivatives
Authors: Reddy Kishorkumar M. , Mugesh Govindasamy
Published: April 2019

Small molecule‐based electrophilic compounds such as 1‐chloro‐2,4‐dinitrobenzene (CDNB) and 1‐chloro‐4‐nitrobenzene (CNB) are currently being used as inhibitors of cysteine‐ and selenocysteine‐containing proteins. CDNB has been used extensively to determine the activity of glutathione S‐transferase and to deplete glutathione (GSH) in mammalian cells. Also, CDNB has been shown to irreversibly inhibit thioredoxin reductase (TrxR), a selenoenzyme that catalyses the reduction of thioredoxin (Trx). Mammalian TrxR has a C‐terminal active site motif, Gly‐Cys‐Sec‐Gly, and both the cysteine and selenocysteine residues could be the targets of the electrophilic reagents. In this paper we report on the stability of a series of cysteine and selenocysteine derivatives that can be considered as models for the selenoenzyme–inhibitor complexes. We show that these derivatives react with H2O2 to generate the corresponding selenoxides, which undergo spontaneous elimination to produce dehydroalanine. In contrast, the cysteine derivatives are stable towards such elimination reactions. We also demonstrate, for the first time, that the arylselenium species eliminated from the selenocysteine derivatives exhibit significant redox activity by catalysing the reduction of H2O2 in the presence of GSH (GPx (glutathione peroxidase)‐like activity), which suggests that such redox modulatory activity of selenium compounds may have a significant effect on the cellular redox state during the inhibition of selenoproteins.
Surface‐Confined SnS2@C@rGO as High‐Performance Anode Materials for Sodium‐ and Potassium‐Ion Batteries
Authors: Li Deping , Sun Qing , Zhang Yamin , Chen Lina , Wang Zhongpu , Liang Zhen , Si Pengchao , Ci Lijie
Published: April 2019

Potassium‐ (PIBs) and sodium‐ion batteries (SIBs) are emerging as promising alternatives to lithium‐ion batteries owing to the low cost and abundance of K and Na resources. However, the large radius of K+ and Na+ lead to sluggish kinetics and relatively large volume variations. Herein, a surface‐confined strategy is developed to restrain SnS2 in self‐generated hierarchically porous carbon networks with an in situ reduced graphene oxide (rGO) shell (SnS2@C@rGO). The as‐prepared SnS2@C@rGO electrode delivers high reversible capacity (721.9 mAh g−1 at 0.05 A g−1) and superior rate capability (397.4 mAh g−1 at 2.0 A g−1) as the anode material of SIB. Furthermore, a reversible capacity of 499.4 mAh g−1 (0.05 A g−1) and a cycling stability with 298.1 mAh g−1 after 500 cycles at a current density of 0.5 A g−1 were achieved in PIBs, surpassing most of the reported non‐carbonaceous anode materials. Additionally, the electrochemical reactions between SnS2 and K+ were investigated and elucidated.
Preface to Special Issue of ChemSusChem—Water Splitting: From Theory to Practice
Authors: Tilley S. David , Selloni Annabella , Hisatomi Takashi
Published: April 2019

In this Editorial, Guest Editors David Tilley, Annabella Selloni, and Takashi Hisatomi introduce the Special Issue of ChemSusChem on Water Splitting: From Theory to Practice. The significance and enormous challenges of sunlight‐driven water splitting are reviewed and the contents of the contributions to the Special Issue are outlined.
Mobile target tracking algorithm for wireless camera sensor networks with adjustable monitoring direction of nodes
Authors: Lu Xu , Zhang Yujing , Liu Jun , Yuan Fei , Cheng Lianglun
Published: April 2019

Wireless camera sensor networks (WCSNs) possess a powerful physical environment monitoring capability. Camera nodes with adjustable monitoring directions further improve their flexibility. This study focuses on tracking multiple mobile targets to investigate the node scheduling and target location evaluation strategy of WCSNs on the basis of rotating nodes. By referring to existing research, this study improves the camera node monitoring and rotation model and proposes three network performance evaluation indicators. The proposed algorithm schedules nodes and their monitoring directions by using the unutilized energy of the nodes and the number of monitored targets. It also predicts the moving trends of the targets and selects active nodes by using the locations and linear speeds of the targets. Experimental results show that the proposed algorithm has a high target tracking accuracy. Compared with traditional target tracking algorithms, the proposed algorithm can effectively reduce the number of active nodes, balance the energy consumption between nodes, and prolong network lifetime.
Intelligent Information‐Centric Networking routing scheme under imprecise information
Authors: Zhang Lingling , Lv Jianhui
Published: April 2019

Information‐Centric Networking (ICN) has been accepted to overcome some weaknesses of the current Internet architecture, showing that “what is being exchanged” is more important than “who are exchanging information.” Given the inadequate considerations on Quality of Service (QoS) and energy saving in ICN routing, we propose in this paper a routing algorithm to enhance the two aspects. At first, on one hand, Cauchy distribution is used as a fuzzy model to evaluate users' QoS requirements, such as bandwidth, delay, and error rate; on the other hand, we formulate energy saving problem to evaluate the green quality of routing algorithm. Then, we design a link selection approach by considering QoS and energy saving, which belongs to a multi‐objective decision problem resolved by intelligent drops algorithm. Finally, we implement the proposed algorithm and compare it with the famous adaptive forwarding mechanism in terms of some significant metrics, and the experimental results reveal that the proposed algorithm is more efficient.
Optimal barrier coverage for critical area surveillance using wireless sensor networks
Authors: Benahmed Tariq , Benahmed Khelifa
Published: April 2019

Intrusion detection using barrier coverage is one of many applications existed in wireless sensor networks. The main purpose of using barrier coverage is to monitor the borders of a specific area against the intruders that are trying to penetrate this critical area by ensuring the total coverage with a low cost and extending the lifetime of the network, many solutions have been proposed in the literature in order to solve the coverage problem in wireless sensor networks, which became a vital field of research. In this paper, we present a new technique based on geometric mathematical models, in order to guarantee the total coverage of our deployed barriers with a minimum possible number of sensors. The idea is to calculate the number of sensors adequate to cover a barrier before deployment. We then formulate the problem to minimize the number of sensors to be deployed to properly cover a barrier; the calculation makes it possible to solve this problem in polynomial using our own heuristic. Additionally, we propose a new mechanism for ensuring a fault‐tolerant network by detecting the faulty sensors and select other suited sensors to close the existing gaps inside the barriers and detecting the sensors whose energy is low before the failure. The obtained simulation results prove the effectiveness of the proposed algorithms.