bluuebunny/crossref_metadata_2025 huggingface dataset:
Extragenic Suppression of a Mutation in Herpes Simplex Virus 1 UL34 That Affects Lamina Disruption and Nuclear Egress
Authors: Vu Amber , Poyzer Chelsea , Roller Richard
Published: September 2016

Nuclear egress of herpesviruses is accompanied by changes in the architecture of the nuclear membrane and nuclear lamina that are thought to facilitate capsid access to the inner nuclear membrane (INM) and curvature of patches of the INM around the capsid during budding. Here we report the properties of a point mutant of pUL34 (Q163A) that fails to induce gross changes in nuclear architecture or redistribution of lamin A/C. The UL34(Q163A) mutant shows a roughly 100-fold defect in single-step growth, and it forms small plaques. This mutant has a defect in nuclear egress, and furthermore, it fails to disrupt nuclear shape or cause observable displacement of lamin A/C despite retaining the ability to recruit the pUS3 and PKC protein kinases and to mediate phosphorylation of emerin. Extragenic suppressors of the UL34(Q163A) phenotype were isolated, and all of them carry a single mutation of arginine 229 to leucine in UL31. Surprisingly, although this UL31 mutation largely restores virus replication, it does not correct the lamina disruption defect, suggesting that, in Vero cells, changes in nuclear shape and gross displacements of lamin A/C may facilitate but are unnecessary for nuclear egress.

IMPORTANCE
Herpesvirus nuclear egress is an essential and conserved process that requires close association of the viral capsid with the inner nuclear membrane and budding of the capsid into that membrane. Access to the nuclear membrane and tight curvature of that membrane are thought to require disruption of the nuclear lamina that underlies the inner nuclear membrane, and consistent with this idea, herpesvirus infection induces biochemical and architectural changes at the nuclear membrane. The significance of the nuclear membrane architectural changes is poorly characterized. The results presented here address that deficiency in our understanding and show that a combination of mutations in two of the viral nuclear egress factors results in a failure to accomplish at least two components of lamina disruption while still allowing relatively efficient viral replication, suggesting that changes in nuclear shape and displacement of lamins are not necessary for herpes simplex virus 1 (HSV-1) nuclear egress.
The Glycosylphosphatidylinositol-Anchored Variable Region of Llama Heavy Chain-Only Antibody JM4 Efficiently Blocks both Cell-Free and T Cell-T Cell Transmission of Human Immunodeficiency Virus Type 1
Authors: Liu Lihong , Wang Weiming , Matz Julie , Ye Chaobaihui , Bracq Lucie , Delon Jerome , Kimata Jason T. , Chen Zhiwei , Benichou Serge , Zhou Paul
Published: September 2016

The variable regions (VHHs) of two heavy chain-only antibodies, JM2 and JM4, from llamas that have been immunized with a trimeric gp140 bound to a CD4 mimic have been recently isolated (here referred to as VHH JM2 and VHH JM4, respectively). JM2 binds the CD4-binding site of gp120 and neutralizes HIV-1 strains from subtypes B, C, and G. JM4 binds gp120 and neutralizes HIV-1 strains from subtypes A, B, C, A/E, and G in a CD4-dependent manner. In the present study, we constructed glycosylphosphatidylinositol (GPI)-anchored VHH JM2 and JM4 along with an E4 control and transduced them into human CD4
+
cell lines and primary CD4 T cells. We report that by genetically linking the VHHs with a GPI attachment signal, VHHs are targeted to the lipid rafts of the plasma membranes. Expression of GPI-VHH JM4, but not GPI-VHH E4 and JM2, on the surface of transduced TZM.bl cells potently neutralizes multiple subtypes of HIV-1 isolates, including tier 2 or 3 strains, transmitted founders, quasispecies, and soluble single domain antibody (sdAb) JM4-resistant viruses. Moreover, transduction of CEMss-CCR5 cells with GPI-VHH JM4, but not with GPI-VHH E4, confers resistance to both cell-free and T cell-T cell transmission of HIV-1 and HIV-1 envelope-mediated fusion. Finally, GPI-VHH JM4-transduced human primary CD4 T cells efficiently resist both cell-free and T cell-T cell transmission of HIV-1. Thus, we conclude that VHH JM4, when targeted to the lipid rafts of the plasma membrane, efficiently neutralizes HIV-1 infection via both cell-free and T cell-T cell transmission. Our findings should have important implications for GPI-anchored antibody-based therapy against HIV-1.

IMPORTANCE
Lipid rafts are specialized dynamic microdomains of the plasma membrane and have been shown to be gateways for HIV-1 budding as well as entry into T cells and macrophages. In nature, many glycosylphosphatidylinositol (GPI)-anchored proteins localize in the lipid rafts. In the present study, we developed GPI-anchored variable regions (VHHs) of two heavy chain-only antibodies, JM2 and JM4, from immunized llamas. We show that by genetically linking the VHHs with a GPI attachment signal, VHHs are targeted to the lipid rafts of the plasma membranes. GPI-VHH JM4, but not GPI-VHH JM2, in transduced CD4
+
cell lines and human primary CD4 T cells not only efficiently blocks diverse HIV-1 strains, including tier 2 or 3 strains, transmitted founders, quasispecies, and soluble sdAb JM4-resistant strains, but also efficiently interferes T cell-T cell transmissions of HIV-1 and HIV-1 envelope-mediated fusion. Our findings should have important implications in GPI-anchored antibody-based therapy against HIV-1.
Single Nucleotide Polymorphisms in Regulator-Encoding Genes Have an Additive Effect on Virulence Gene Expression in a Vibrio cholerae Clinical Isolate
Authors: Carignan Bailey M. , Brumfield Kyle D. , Son Mike S.
Published: September 2016

Cholera, an infectious disease of the small intestine caused by the aquatic bacterium
Vibrio cholerae
, often results in vomiting and acute watery diarrhea. If left untreated or if the response is too slow, the symptoms can quickly lead to extreme dehydration and ultimately death of the patient. Recent anecdotal evidence of cholera patients suffering from increasingly severe symptoms and of disease progression at a much higher rate than previously observed has emerged. As recent cholera outbreaks caused by increasingly virulent strains have resulted in higher mortality rates, the need to investigate the mechanism(s) allowing this observed increased virulence is apparent. The significance of our research is in identifying the mechanism for increased virulence capabilities, which will allow the development of a model that will greatly enhance our understanding of cholera disease and
V. cholerae
pathogenesis, leading to broader biomedical impacts, as cholera serves as a model for other enteric diarrheal diseases.
Obesity in adolescents with chronic fatigue syndrome: an observational study
Authors: Norris T , Hawton K , Hamilton-Shield J , Crawley E
Published: September 2016

Objective

Identify the prevalence of obesity in patients with chronic fatigue syndrome (CFS) compared with healthy adolescents, and those identified with CFS in a population cohort.

Design

Cross-sectional analysis of multiple imputed data.

Setting

Data from UK paediatric CFS/myalgic encephalomyelitis (CFS/ME) services compared with data collected at two time points in the Avon Longitudinal Study of Parents and Children (ALSPAC).

Patients

1685 adolescents who attended a CFS/ME specialist service between 2004 and 2014 and 13 978 adolescents aged approximately 13 years and 16 years participating in the ALSPAC study.

Main outcome measures

Body mass index (BMI) (kg/m2), sex-specific and age-specific BMI Z-scores (relative to the International Obesity Task Force cut-offs) and prevalence of obesity (%).

Results

Adolescents who had attended specialist CFS/ME services had a higher prevalence of obesity (age 13 years: 9.28%; age 16 years: 16.43%) compared with both adolescents classified as CFS/ME in ALSPAC (age 13 years: 3.72%; age 16 years: 5.46%) and those non-CFS in ALSPAC (age 13 years: 4.18%; age 16 years: 4.46%). The increased odds of obesity in those who attended specialist services (relative to non-CFS in ALSPAC) was apparent at both 13 years (OR: 2.31 (1.54 to 3.48)) and 16 years, with a greater likelihood observed at 16 years (OR: 4.07 (2.04 to 8.11)).

Conclusions

We observed an increased prevalence of obesity in adolescents who were affected severely enough to be referred to a specialist CFS/ME service. Further longitudinal research is required in order to identify the temporal relationship between the two conditions.
Pharmacokinetic-guided dosing of factor VIII concentrate in a patient with haemophilia during renal transplantation
Authors: Hazendonk Hendrika C A M , Kruip Marieke J H A , Mathôt Ron A A , Cnossen Marjon H
Published: September 2016

A 29-year-old man with severe haemophilia A and end-stage renal disease underwent a renal transplantation. To prevent bleeding, patient was treated with replacement therapy using factor VIII (FVIII) concentrate, according to National guidelines. Bayesian analysis was performed by combining observed FVIII concentrations with a population pharmacokinetic (PK) model for patients with severe haemophilia A in a perioperative setting. Application of Bayesian analysis led to accurate prediction of observed concentrations after prescribing dosing advice. We believe that PK-guided dosing of factor concentrates is a valuable step towards further individualisation of treatment in patients with bleeding disorders, especially in those patients requiring precise targeting of coagulation factor levels due to high risk of either bleeding or thrombosis, as illustrated by this patient undergoing a major surgical procedure.
Can a mobile app improve the quality of patient care provided by trainee doctors? Analysis of trainees’ case reports
Authors: Webb Katie , Bullock Alison , Dimond Rebecca , Stacey Mark
Published: September 2016

Objectives

To explore how a medical textbook app (‘iDoc’) supports newly qualified doctors in providing high-quality patient care.

Design

The iDoc project, funded by the Wales Deanery, provides new doctors with an app which gives access to key medical textbooks. Participants’ submitted case reports describing self-reported accounts of specific instances of app use. The size of the data set enabled analysis of a subsample of ‘complex’ case reports. Of the 568 case reports submitted by Foundation Year 1s (F1s)/Year 2s (F2s), 142 (25%) detailed instances of diagnostic decision-making and were identified as ‘complex’. We analysed these data against the Quality Improvement (QI) Framework using thematic content analysis.

Setting

Clinical settings across Wales, UK.

Participants

Newly qualified doctors (2012–2014; n=114), F1 and F2.

Interventions

The iDoc app, powered by Dr Companion software, provided newly qualified doctors in Wales with a selection of key medical textbooks via individuals’ personal smartphone.

Results

Doctors’ use of the iDoc app supported 5 of the 6 QI elements: efficiency, timeliness, effectiveness, safety and patient-centredness. None of the case reports were coded to the equity element. Efficiency was the element which attracted the highest number of case report references. We propose that the QI Framework should be expanding to include ‘learning’ as a 7th element.

Conclusions

Access to key medical textbooks via an app provides trusted and valuable support to newly qualified doctors during a period of transition. On the basis of these doctors’ self-reported accounts, our evidence indicates that the use of the app enhances efficiency, effectiveness and timeliness of patient-care in addition consolidating a safe, patient-centred approach. We propose that there is scope to extend the QI Framework by incorporating ‘learning’ as a 7th element in recognition of the relationship between providing high-quality care through educational engagement.
Were they in the loop during automated driving? Links between visual attention and crash potential
Authors: Louw Tyron , Madigan Ruth , Carsten Oliver , Merat Natasha
Published: September 2016

Background

A proposed advantage of vehicle automation is that it relieves drivers from the moment-to-moment demands of driving, to engage in other, non-driving related, tasks. However, it is important to gain an understanding of drivers’ capacity to resume manual control, should such a need arise. As automation removes vehicle control-based measures as a performance indicator, other metrics must be explored.

Methods

This driving simulator study, conducted under the European Commission (EC) funded AdaptIVe project, assessed drivers’ gaze fixations during partially-automated (SAE Level 2) driving, on approach to critical and non-critical events. Using a between-participant design, 75 drivers experienced automation with one of five out-of-the-loop (OOTL) manipulations, which used different levels of screen visibility and secondary tasks to induce varying levels of engagement with the driving task: 1) no manipulation, 2) manipulation by light fog, 3) manipulation by heavy fog, 4) manipulation by heavy fog plus a visual task, 5) no manipulation plus an n-back task.

Results

The OOTL manipulations influenced drivers’ first point of gaze fixation after they were asked to attend to an evolving event. Differences resolved within one second and visual attention allocation adapted with repeated events, yet crash outcome was not different between OOTL manipulation groups. Drivers who crashed in the first critical event showed an erratic pattern of eye fixations towards the road centre on approach to the event, while those who did not demonstrated a more stable pattern.

Conclusions

Automated driving systems should be able to direct drivers’ attention to hazards no less than 6 seconds in advance of an adverse outcome.
Who to handover: a case–control study of a novel scoring system to prioritise handover of internal medicine inpatients
Authors: Bittman Jesse , Tam Penny , Little Chris , Khan Nadia
Published: September 2016

Background

Handover of patients between care providers is a critical event in patient care. There is, however, little evidence to guide the handover process, including determining which patients to handover.

Aim

Compare the ability of gestalt-based handover with two structured scores, the modified early warning score (MEWS) and our novel iHAND clinical decision support system, to predict which patients will be assessed by a physician overnight.

Methods

This case–control study included 90 inpatients, comprising 32 patients assessed overnight (cases) and 58 patients not assessed overnight (controls) at a teaching hospital in British Columbia, Canada (May 2012). Gestalt, MEWS and iHAND scores were analysed against patients seen overnight using logistic regression and receiver-operating characteristic (ROC) curves.

Results

Neither current gestalt-based handover practice (odds ratio (OR) 1.50, 95% CI 0.89 to 3.83) nor MEWS (OR 0.96, 95% CI 0.75 to 1.24, area under the ROC curve (AUC) 0.61, 95% CI 0.49 to 0.73) were significantly associated with need to be seen overnight. The iHAND score was associated with need to be seen (OR 1.93, 95% CI 1.24 to 3.02, AUC 0.70, 95% CI 0.60 to 0.81).

Conclusions

The iHAND score had moderate ability to predict which patients required assessment overnight, while MEWS score and current gestalt approach correlated poorly, suggesting the iHAND score may help prioritisation of patients likely to be seen overnight for handover.
HAS THE INDUSTRIAL STRUCTURE OF WESTERN PROVINCES IN CHINA BEEN DIFFERENTIAL? EVIDENCE FROM THE SIP FRAMEWORK
Authors: SHI JUNWEI , FU HAIYAN
Published: September 2016

The Structure–Industry–Project (SIP) framework is developed to account for the evolution of industrial structure in less-developed regions. The dynamic relationship between structure, industry and project is investigated from an integrative perspective, which is utilized to assess the role of national policy in reshaping the regional industrial structure. A new indicator is constructed to measure the differentiation of industrial structure of a province by employing data from 29 secondary industries of western provinces of China from 2000 to 2010. The basic result shows that the differentiation of industrial structure decreased instead of increasing during the past decade. Empirical evidence demonstrates that the dysfunction of the SIP interaction leads to decreasing differentiation of the industrial structure in a province. Specifically, the change of key industry is positively associated with the differentiation of industrial structure, whereas the role of project works in a contingent way. Moreover, the project in resource-industries plays a significant role in facilitating the differentiation of industrial structure while the projects in technology-intensive and high-tech industries do nothing. The findings in this study can provide suggestion for the government to improve the effect of development policies on the optimization of industrial structure in less-developed economies.
Diffraction Efficiency Testing of Sinusoidal and Blazed Off-Plane Reflection Gratings
Authors: Tutt James H. , McEntaffer Randall L. , Marlowe Hannah , Miles Drew M. , Peterson Thomas J. , DeRoo Casey T. , Scholze Frank , Laubis Christian
Published: September 2016

Reflection gratings in the off-plane mount have the potential to enhance the performance of future high resolution soft X-ray spectrometers. Diffraction efficiency can be optimized through the use of blazed grating facets, achieving high-throughput on one side of zero-order. This paper presents the results from a comparison between a grating with a sinusoidally grooved profile and two gratings that have been blazed. The results show that the blaze does increase throughput to one side of zero-order; however, the total throughput of the sinusoidal gratings is greater than the blazed gratings, suggesting the method of manufacturing the blazed gratings does not produce precise facets. The blazed gratings were also tested in their Littrow and anti-Littrow configurations to quantify diffraction efficiency sensitivity to rotations about the grating normal. Only a small difference in the energy at which efficiency is maximized between the Littrow and anti-Littrow configurations is seen with a small shift in peak efficiency towards higher energies in the anti-Littrow case. This is due to a decrease in the effective blaze angle in the anti-Littrow mounting. This is supported by PCGrate-SX V6.1 modeling carried out for each blazed grating which predicts similar response trends in the Littrow and anti-Littrow orientations.
An enigmatic echinoid spine from south Devon, UK: Devonian or Cretaceous?
Authors: Donovan S. K. , Fearnhead F. E.
Published: September 2016

Echinoids are poorly known from the Devonian of SW England. This report records an external mould of a solitary primary spine in a chert cobble collected from near the site of Wolborough Quarry, SW Devon, a well-known Middle Devonian palaeontological site. However, cherts are rare in Devonian limestones of south Devon and the spine is unusually robust in comparison with those of other Devonian taxa. The cobble is here interpreted as an erratic, most probably an Upper Cretaceous flint, and the spine is identified as
Prionocidaris
sp. cf.
P. vendocinensis
(Agassiz & Desor). This is another illustration of the high fidelity possible in fossils preserved in cherts even after reworking.
Notes on new xiphosurid (horseshoe crab) trackways from the Middle Jurassic of the Cleveland Basin, Yorkshire, UK
Authors: Romano Mike , Taylor Robert
Published: September 2016

Two previously unrecorded invertebrate trackway types,
Kouphichnium
. isp. indet. and
Kouphichnium
cf.
arizonae
, are described from the Middle Jurassic Saltwick Formation of the Cleveland Basin, Yorkshire. The trackways are considered to have been made by limulids in an interdistributary bay environment.
Tidally influenced shoal water delta and estuary in the Middle Jurassic of the Søgne Basin, Norwegian North Sea: sedimentary response to rift initiation and salt tectonics
Authors: Mellere Donatella , Mannie Aruna , Longhitano Sergio , Mazur Mike , Kulausa Hyelni , Brough Samme , Cotton James
Published: September 2016

Recent studies in the Middle Jurassic Bryne and Sandnes formations, primary reservoirs in several fields across the Norwegian and Danish North Sea, show the widespread occurrence of tidal-influenced and tide-dominated deposits. Aalenian–Bajocian Bryne cores reflect deposition by a shoal water, tidally influenced delta onto a low wave energy tidal platform (both supratidal and intertidal) that probably occupied the majority of the Søgne Basin, a narrow rift system connected to the Central and Danish graben and transgressed from an open-marine basin, possibly located to the south. At the Bathonian–Callovian boundary, a new phase of rifting and progressive salt movements led to the deposition of the upper Bryne and Sandnes formations within an 80–100 km long composite estuarine valley. Basin tilting to the south and continued transgression resulted in tidal deltas that offlap the northern margin of the basin. The basin was fully transgressed by the end of the Callovian. From the Late Bathonian onwards, differential tectonic movements along the broadly interconnected Middle Jurassic rift basins led to a change in the transgression direction from south to north, with an open-marine basin located in the Central and Viking graben.
Design Study of a Novel, Semi-Solid Li/O2 Redox Flow Battery
Authors: Soavi Francesca , Ruggeri Irene , Arbizzani Catia
Published: September 2016

Here we report about the design optimization of a new battery, a non-aqueous Semi-solid Lithium Redox Flow Air (O2) Battery (SLRFAB) which operates using a semi-solid organic catholyte. Oxygen Redox Reaction (ORR) takes place at the semi-solid electroactive particles dispersed in the catholyte, avoiding the electrode passivation that usually occurs in a conventional Li/O2 battery, enhancing the capacity and, in turn, the delivered energy. The results of the galvanostatic tests at different currents and flow rates and the practical prototype energy and power are here reported. We demonstrate that up to 700 Wh kg-1 and 70 W kg-1 is achievable by the optimization of the SLRFAB catholyte composition and current collector size. The strategies to reach and overcome such outstanding results are discussed on the basis of the experimental performance of a lab-scale SLRFAB prototype.
Effect of Ti(IV) Ion on Mn(III) Stability in Ti/Mn Electrolyte for Redox Flow Battery
Authors: Kaku Hirokazu , Dong Yong-Rong , Hanafusa Kei , Moriuchi Kiyoaki , Shigematsu Toshio
Published: September 2016

The mixed electrolyte of titanium and manganese is one of the promising candidates as low-cost electrolytes for redox flow batteries. In this study, the effect of Ti4+ ion in the positive electrolyte was examined in detail. With an increase of Ti4+ ion concentration, the formation reaction of MnO2 particle was slowed down significantly, which means the stability of Mn3+ ion is enhanced. Moreover, the particle size of MnO2 precipitate became smaller in electrolytes containing certain amount of Ti4+ ion. These MnO2 particles were small enough to be flowed in the electrolyte and to be reduced to Mn2+ ion again. Ti4+ ion also affected the crystal structures of MnO2, limiting to gamma-MnO2 which is assumed to be reactive. In cyclic voltammetry study, the higher Ti4+ ion concentration was, the better reversibility of Mn redox reaction was observed. The ion interaction between Ti4+ and Mn3+ was confirmed by UV-visible spectroscopy.
Preliminary Study of a Reversible Hydrogen-Vanadium Flow Battery
Authors: Dowd Regis Paul , Ying Andrew , Nguyen Trung Van
Published: September 2016

A hydrogen-vanadium flow battery was assembled using a Pt/C hydrogen electrode, a high surface area carbon nanotube (CNT) vanadium electrode, and interdigitated flow fields at both electrodes. By using a reference electrode to measure half-cell performances, membrane losses and vanadium crossover effects on the hydrogen electrode were identified. Peak power density of greater than 530 mW/cm2 was obtained. Cycling studies at high current density, 300 mA/cm2, were conducted, and an overall energy efficiency of greater than 60% was obtained.
Core-Shell Rhodium Sulfide Catalyst for HER/HOR in HBr Solution
Authors: Li Yuanchao , Nguyen Trung Van
Published: September 2016

Synthesis and characterization of high electrochemical surface area core-shell RhxSy catalysts for HER/HOR in HBr solution are discussed. Catalysts with RhxSy as shell and different percentage (5%, 10%, and 20%) platinum on carbon as core material are synthesized. Cyclic voltammetry was used to evaluate the Pt- equivalent mass specific ECSA and durability of these catalysts. The results show that the catalyst with core-shell structure has better performance compared to commercial catalyst (RhxSy/C catalyst from BASF). XRD, XPS and TEM were used to characterize the bulk and surface compositions and to confirm the core-shell structure of the catalysts, respectively.
The State of Charge of Electrodes and Its Effects on Lithium-Iron-Phosphate Battery Simulation
Authors: Huang Hsuan-Han , Chung Wei-Lun , Liao Kuo-Chi , Lee Ching-Fei , Tien Jhen-Yang , Young Hong-Tsu , Chen Hsun-Yi
Published: September 2016

Accuracy of simulated LFP battery characteristics, including the cell voltage, lithium concentration distribution, and cell capacity, are highly related to the solid-phase initial concentrations of each individual electrode. To determine the initial concentrations of individual electrodes of the LFP battery, equilibrium potentials are experimentally measured by low-rate discharge while the characteristic points are calculated by identifying critical points of the discharge curves. The LFP battery model with such formally determined concentrations is validated by comparing the simulated discharge curves with experimental measurements under various loading demands. Further understanding of the effects of lithium loss during activation process with experiments and model simulation can assist the LFP battery design and optimize fabrication.
Modeling Battery Performance Due to Intercalation Driven Volume Change in Porous Electrodes
Authors: Garrick Taylor Reed , Dai Yiling , Higa Kenneth , Srinivasan Venkat , Weidner John W.
Published: September 2016

A mathematical battery model is presented that incorporates the dimensional and porosity changes in porous electrodes caused by volume changes in the active material during intercalation. Porosity and dimensional changes in an electrode can significantly affect the resistance of the battery during cycling. In addition, volume changes generate stresses in the electrode, which can lead to premature failure of the battery. Here, material conservation equations are coupled with the mechanical properties of porous electrodes to link dimensional and porosity changes to stresses and the resulting resistances that occur during the intercalation processes. The stress-strain relationships used in this model are from previous works, which are used to predict porosity and dimensional changes, and were established by comparing thermal rock expansion and electrode expansion due to intercalation. Several different battery casings are examined and operating curves are predicted based off of standard equilibrium potentials combined with simple kinetics.
Two-Dimensional Thermal Modeling of Lithium-Ion Battery Cell Based on Electrothermal Impedance Spectroscopy
Authors: Swierczynski Maciej , Stroe Daniel Ioan , Knap Vaclav , Kær Søren Knudsen , Teodorescu Remus
Published: September 2016

Thermal modeling of lithium-ion batteries is gaining its importance together with increasing power density and compact design of the modern battery systems in order to assure battery safety and long lifetime. Thermal models of lithium-ion batteries are usually either expensive to develop and accurate or equivalent thermal circuit based with moderate accuracy and without spatial temperature distribution. This work presents initial results that can be used as a fundament for the cost-efficient development of the two-dimensional thermal model of lithium-ion battery based on multipoint electrothermal impedance spectroscopy.
Safety Testing with Nonwoven Nanofiber Separators: Comparing Shutdown Separators to Thermally Stable Separators
Authors: Morin Brian , Hu Carl , Khokhlov Pavel , Kaschmitter James , Cho Sung-Jin
Published: September 2016

Pouch cells of LiFePo4 and graphite at 2700 mAh capacity were made from commercial electrodes with four different separators: 25 micron polypropylene (PP), 25 micron ceramic coated polyethylene (PE/C), 25 micron nanofiber nonwoven (Dreamweaver Silver – DWI/S), and 25 micron nanofiber nonwoven containing para-aramid fibers (Dreamweaver Gold – DWI/G). The cells had nearly identical electrical performance. The cells underwent hard short, overcharge, hot box and nail penetration tests. All cells passed hard short and overcharge tests. In hot box tests, the PE/C and PP cells experienced internal shorts when the cell temperature reached 145 C. The DWI/S and DWI/G cells showed a steady voltage for 1 hour, and continued to function after the test was completed. In the nail penetration test, the PP and PE/C cells experienced an immediate drop to zero voltage, and the temperature rose quickly to 115 C (PE/C) and 85 C (PP). The DWI/S and DWI/G cells rose to 60 C and 40C respectively, but exhibited only a ~100 mV drop in voltage and continued to function with the nail in the cell. Autopsies of the cells revealed significant shrinkage and cracking of the polyolefin separators, but primarily mechanical damage to the DWI separators.
Half-Cell Electrochemical Performance of Hybridized Ionic Liquid Additives for Zinc/Bromine Flow Battery Applications
Authors: Rajarathnam Gobinath Pillai , Vassallo Anthony
Published: September 2016

The effects of employing hybrid ionic liquid (IL) mixtures as bromine sequestration agents in zinc/bromine (Zn/Br) flow batteries are investigated. The ILs 1-ethyl-3-methylimidazolium bromide ([C2MIm]Br) and 1-ethyl-1-methylpyrrolidinium bromide ([C2MPyrr]Br) are studied within Zn/Br electrolytes in different mixing proportions at glassy carbon electrodes. Cyclic voltammetry showed beneficial performance in the Zn and Br half-cells when utilizing pure [C2MIm]Br and [C2MPyrr]Br, respectively. Consequently, it is recommended that electrolytes containing single IL types are better suited for Zn/Br systems compared to those utilizing hybrid mixtures. Electrochemical impedance spectroscopy showed that low diffusion limitations and charge-transfer resistance in both half-cells, as well as low Zn-side polarization resistance, contribute towards beneficial voltammetry performance. Scanning electron microscopy, X-ray diffraction and Williamson–Hall analysis of zinc electrodeposited during battery charging showed that the type and proportion of IL present influences crystal morphology and size. These findings warrant further investigation into full-cell testing, as well fundamental studies on the behavior and influence of other hybrid IL formulations for Zn/Br system applications. The methods and findings presented in this work are also applicable to electrodeposition and redox flow batteries which utilize pure or hybrid ILs for bromine sequestration purposes.
Towards Electron Transfer Compounds with Rigid Resistor Units
Authors: Locke Gemma M. , Senge Mathias O.
Published: September 2016

There is a growing need to access small rigid scaffolds for use in organic and medicinal chemistry. It is a requirement of many systems that the substituents are arranged in a precisely known, specific and invariable orientation. The applications of such scaffold span from host–guest interactions, photosynthesis, light harvesting and energy transfer amongst others. Both triptycene and cubane are rigid three dimensional scaffolds which are capable of arranging substituents in such a spatially defined manner. As a result they are ideal candidates for the synthesis of multiporphyrin arrays, to be used as photosynthetic mimics. In this work transition metal catalyzed cross coupling methodologies such as Suzuki, Sonogashira and Stille reactions have been implemented to successfully attach porphyrins to these hydrocarbon scaffolds.
(Invited) Deep Silicon Etching - Increasingly Relevant >20 Years on!
Authors: Thomas Dave , Muggeridge Matthew , Hopkins Janet , Launay Nicolas , Ashraf Huma , Barrass Tony
Published: September 2016

In the early 1990’s researchers at the Robert Bosch facility in Stuttgart invented a novel method of etching very deep features into silicon. This led to a patent being granted in 1994. Originally intended as a method of fabricating devices for the then emerging automotive MEMS sector, its use has since diversified to cover virtually all other MEMS markets. Most recently the use of the Bosch Process has expanded into through silicon via (TSV) etching in 3D packaging applications. This paper describes what is possible today using the Bosch process and will consider future applications and uses. The diversity of the approach is illustrated through various examples including cavities etched at high rates, features with aspect ratios of 90:1, profile tilt to ~±0.15°, TSVs for wafer stacking and the increasing demand for more precise control including end-point detection down to 0.05% open area.
Electroless Metallization of Stereolithographic Photocurable Resins for 3D Printing
Authors: Bernasconi Roberto , Credi Caterina , Natale Gabriele , Tironi Marco , Cuneo Federico , Levi Marinella , Magagnin Luca
Published: September 2016

In the present paper the electroless metallization of 3D printed parts using stereolithography is investigated. Two different photocurable resins of large commercial diffusion and a self-formulated one are used as starting materials for printing. A first metal layer of NiP or Cu, obtained by an optimized pretreatment and plating process, is subsequently applied on the parts. It is also demonstrated the possibility of obtaining multilayers through the successive electrodeposition of different metals on the electroless treated parts. The resulting layers are characterized by SEM and profilometry.
Morphology and Electrical Properties of Copper Thin Films Electroplated on Ni/n+-Si(100) for Silicon Solar Contact
Authors: Mebarki Mourad , Moussi Abderrahmane , Azizi Amor , Khelladi Mohamed redha , Mahiou Linda
Published: September 2016

Cu thin films were electrodeposited on Ni/n+-Si(100) substrate from sulfuric solution with fixed pH at room temperature. The effect of deposition time of Cu coatings was studied by using the chronoamperometry method (CA), the atomic force microscopy (AFM), X-ray diffraction (XRD) and four point probe to investigate surface topography , structure and electrical properties of Cu films. From electrochemical measurements, the Cu film thickness ranging from 63 nm to 8.9 µm was calculated using Faraday’s law. The AFM study showed a rugose surface of the Cu films and the variation of film morphology with deposition time were established. The XRD spectra revealed the formation of thin Cu films with a preferential orientation. Sheet resistance and resistivity showed strong dependence on the deposition time of Cu films. Cu films will be in the future metal contact for silicon solar cells.
(Industrial Electrochemistry and Electrochemical Engineering Division Student Achievement Award) Engineering the Ionic Polymer Phase Surface Properties of a PEM Fuel Cell Catalyst Layer
Authors: Dowd Regis Paul , Day Cynthia S , Nguyen Trung Van
Published: September 2016

During high power density operations, the performance of polymer electrolyte membrane fuel cells (PEMFCs) is limited by high water saturation levels in the cathode catalyst layer due to high wettability of the ionic polymer phase. A new heat treatment was used to create and permanently lock-in the surface structure of a biphasic membrane (Nafion® 212). Several surface characterization techniques were used to verify the engineered membrane’s surface after heat treatment, including contact angle, multi-mode atomic force microscopy (AFM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). We found that specific heat treatment conditions will lead to the formation of either a hydrophobic or hydrophilic surface layer. The results of this research will guide the design of a new class of PEMFC catalyst layers. Engineered PEMFC catalyst layers are expected to prevent electrode flooding, therefore leading to higher performance and efficiency during high power density operations.
Simulation Study of Electrolyte Flow and Slime Particle Transport in a Newly Designed Copper Electrorefining Cell
Authors: Zeng Weizhi , Free Michael L , Wang Shijie
Published: September 2016

A model based in COMSOL Multiphysics (a finite element analysis software) consisting of a specially designed electrorefining cell was developed to simulate copper electrorefining. This cell has its inlet on the side wall near the cell top and its outlet on the opposite side wall near the cell bottom. Copper concentration profile was acquired as electrochemical simulation results. Electrolyte flow velocity field and slime particle trajectory were obtained as fluid flow and particle transport simulation results. Features of the copper concentration profile, the electrolyte flow field, and the slime particle transport are discussed. The simulation results of this cell are compared with those of a lab-scale conventional cell, and some advantages of this cell can be found: cupric ions in the cell are more uniformly distributed with better convection in the inter-electrode domain; slime particles are more likely to settle to the cell bottom without affecting the cathode purity.
Effect of RTILs on the Hydrogen Evolution Reaction in Alkaline Media
Authors: Amaral Luís , Cardoso David , Sljukic Biljana , Santos Diogo M.F. , Sequeira Cesar A.C.
Published: September 2016

Three 1-ethyl-3-methylimidazolium [Emim]-based room temperature ionic liquids (RTILs), namely [Emim][Ac] (acetate), [Emim][EtSO4] (ethylsulfate) and [Emim][MeSO3] (methanesulfonate), were tested as additives in alkaline solutions for hydrogen evolution reaction (HER). Electrochemical measurements were performed with a platinum foil working electrode at 25 ºC in 8 M KOH solution and after adding 1-2 vol.% of each ionic liquid. From the polarization curves, Tafel plots were constructed and the main kinetic parameters were obtained for all different electrolytes. Higher currents were found after [Emim][MeSO3] addition. Electrochemical impedance spectroscopy measurements revealed a significant decrease of the overall impedance in the RTILs added electrolytes.
Thin Film Catalysts: Ni5P4 (Cathodic) and LiCoO2 (Anodic) for Electrolysis of Water
Authors: Hwang Shinjae , Porter Spencer H , Gardner Graeme , Laursen Anders B. , Wang Hao , Li Mengjun , Amarasinghe Voshadhi , Taghaddos Elaheh , Safari Ahmad , Garfunkel Eric , Greenblatt Martha , Dismukes Gerard Charles
Published: September 2016

Inexpensive earth-abundant catalysts are required to accelerate both the oxidative and reductive half reactions for electrolysis of water. Using natural enzymes as models, such as the CaMn4O5 cubane motif in the water oxidizing complex of photosystem II and the Ni-S active site of Ni-Fe hydrogenase, we previously developed cubic LiCoO2 and nickel phosphides that mimic their chemistry, respectively. Here we prepared thin films of spinel – LiCo2O4, for the (water oxidation) oxygen evolving reaction (OER), and Ni5P4, for the hydrogen evolving reaction (HER) on Au substrates. We investigated their atomic structure (PXRD), Raman vibrational modes, surface morphology (SEM, AFM), core electronic levels (XPS), and electrochemical catalytic performance. These non-precious metal thin film materials function as well as the individual nanocrystalline particles and are expected to be applicable to use in monolithic photoelectrochemical cells and potentially fuel cells.
Evaluation of a Second-Generation Bulky Cation for Anion Exchange Membranes
Authors: Liu Ye , Zhang Bingzi , Yan Yushan , Liberatore Matthew W , Herring Andrew M
Published: September 2016

Researchers worldwide have developed bulky cations for incorporation into anion exchange membranes (AEMs) used in energy transfer and storage devices. The bulky cations increase chemical stability by attaching electron-donating groups to the central cation. In this work, we compared the performance of the bulky tris(2,4,6-trimethoxy phenyl) phosphonium cation (TPQP) to the much smaller benchmark trimethylammonium cation (TMA) commonly utilized in alkaline fuel cells. The TPQP cation exhibits higher thermal and chemical stability than the TMA cation. Polyphenylene oxide (PPO) membranes functionalized with TPQP cation show comparable anion1ic conductivity values to similar membranes functionalized with TMA cation. Mechanical testing of 15 μm membranes of the tris(2,4,6-trimethoxy phenyl) phosph- onium functionlized PPO (PPO-TPQP) indicates that in order to meet the demands of commercial applications, Young’s modulus will need to be reduced and membrane elongation need to be increased.
Electrochemical Characterization of Novel Organoborohydride Compounds
Authors: Cardoso David , Sequeira Cesar A.C. , Bateman Chris , Barker Josh , Abbey Eric , Santos Diogo M.F.
Published: September 2016

Sodium borohydride (NaBH4) has wide application as a reducing agent in organic and inorganic synthesis. In this work, sodium benzylborohydride (C7H7BH3Na) and sodium phenylborohydride (C6H5BH3Na) are synthesized and a direct relationship between the organic substituents and the reducing power of the borohydride center is investigated. Platinum and gold disk macroelectrodes and microelectrodes are used to study the electrooxidation of these organoborohydride compounds. Chronoamperometry and cyclic voltammetry measurements are carried out in dimethyl sulfoxide (DMSO) solution using 0.001 M of each compound at temperatures ranging from 25 to 65 ºC. The results are directly compared to those obtained with NaBH4 solutions in the same experimental conditions. The main electrochemical parameters are evaluated, including number of exchanged electrons, charge transfer coefficients, reaction orders and diffusion coefficients. Moreover, the activation energy for the borohydride oxidation reaction is calculated assuming Arrhenius behavior for the selected range of temperatures.
Palladium Nanoparticles Supported on 3D-Graphene Nanosheets for Oxygen Reduction Reactions in Alkaline Media
Authors: Kabir Sadia , Serov Alexey , Atanassov Plamen
Published: September 2016

The electrochemical reduction of oxygen on palladium nanoparticles supported on 3D-Graphene nanosheets was investigated in alkaline media. The Pd nanoparticles were synthesized using a surfactant-free soft alcohol reduction method (SARM). The 3D-Graphene sheets were given a porous morphology using sacrificial silica templates. Scanning and Transmission electron micrographs showed that Pd nanoparticles of an average size of ~5-6 nm were evenly dispersed on porous 3D-Graphene sheets. Rotating ring disc electrode (RRDE) measurements showed significantly enhanced activity of Pd/3D-Graphene catalysts (4-electron oxygen reductions pathway) compared to Pd/Vulcan. The remarkable performance of the Pd/3D-Graphene catalysts was attributed to their (i) higher degree of graphitization providing efficient charge transfer ability, (ii) good dispersion of nanoparticle (iii) porous network of channels embedded into the 3D-graphene matrix using a sacrificial support method (SSM).
The Performance of Hard Carbon in a Sodium Ion Battery and Influence of the Sodium Metal in Observed Properties
Authors: Ledwoch Daniela , Brett Daniel J.L , Kendrick Emma
Published: September 2016

This investigation includes the electrochemical testing protocols for a hard carbon sodium ion anode material, and discusses the use of a sodium metal counter electrode with respect to the material and cell stability during the electrochemical testing. A 3-electrode cell in compression fitting (‘Swagelok’) configuration was used with hard carbon as the working electrode and sodium metal as the counter and reference electrode. The cells were charged and discharged at high rates to investigate the polarisation effects of the sodium metal. The results indicate a significant contribution from the sodium metal electrode to the observed cell characteristics, depending on state-of-charge and rate. These contributions are significant and may lead to misinterpretation of the material and electrode performance when tested in 2-electrode arrangements with a sodium metal counter electrode.
The Analysis of Prussian Blue Bonding on Electrochemically Functionalized Carbon Nanotubes
Authors: Je Lisa , Smart Christopher J. , Belli Stuart
Published: September 2016

Carbon nanotubes (CNTs) have been deposited by chemical vapor deposition (CVD) onto a nickel catalyst that had been electroplated onto a metal base electrode. The CNTs were characterized by Cyclic Voltammetry (CV) and Scanning Electron Microscopy (SEM). Prussian Blue (PB) was electrochemically deposited onto the CNT electrode from a solution of K3Fe(CN)6 by repeated cycling between -0.1 V and 0.8 V verses an Ag/AgCl reference. The ferricyanide redox couple occurs approximately at 0.25V-0.5 V while the deposition of PB was seen as a growing redox couple approximately at 0.65V-1.0 V. This suggests that utilizing CV is a viable method to functionalize CNT electrodes with PB. However, the exact structure and location of the PB bonding is unknown and was the focus of this study. SEM was utilized to image the electrode surface after each step of the functionalization process in order to study PB bonding onto the CNT electrode.
A Pulse Voltage Application in Electrochemical Reduction of Solid CaWO4 Powder
Authors: Goksu Gokce , Erdogan Metehan , Karakaya Ishak
Published: September 2016

Scheelite is the most abundant mineral of tungsten, but wolframite is used more than scheelite due to easier dissolution in alkaline solutions used in present processing methods. An alternative method based on electrochemical reduction of CaWO4 by direct current applications in molten salt solutions was recently reported. Pulse voltage and constant voltage reduction mechanisms were compared and an optimization of reduction kinetics was achieved in this study. The results have shown that faster reduction rates could be achieved during pulse voltage applications compared to constant voltage applications, when average value of pulse voltage application was the same as its constant counterpart. Furthermore, analysis of charge, energy and theoretical reduction graphs showed that reduction of calcium tungstate occurs at higher potential differences than 2.2 V, between calcium tungstate and graphite.
(Invited) Silicon Nanostructures: A Versatile Material for Photonics
Authors: Bisadi Zahra , Cortelletti Paolo , Zanzi Andrea , Piotto Chiara , Fontana Giorgio , Bettotti Paolo , Scarpa Marina , Pavesi Lorenzo
Published: September 2016

Silicon is the most common semiconductor in technology. Its main limit is the lacking of efficient light emission properties. Here quantum effects are exploited to fabricate optically active silicon photonics elements. The manuscript reports recent results obtained in different research fields spanning from bio- to integrated-photonics and nonlinear optics.