Ti surface doping of LiNi0.5Mn1.5O4−δ positive electrodes for lithium ion batteries

The particle surface of LiNi_0.5Mn_1.5O_4−δ (LNMO), a Li-ion battery cathode material, has been modified by Ti cation doping through a hydrolysis–condensation reaction followed by annealing in oxygen. The effect of different annealing temperatures (500–850 °C) on the Ti distribution and electrochemical performance of the surface modified LNMO was investigated. Ti cations diffuse from the preformed amorphous ‘TiO_x’ layer into the LNMO surface during annealing at 500 °C. This results in a 2–4 nm thick Ti-rich spinel surface having lower Mn and Ni content compared to the core of the LNMO particles, which was observed with scanning transmission electron microscopy coupled with compositional EDX mapping. An increase in the annealing temperature promotes the formation of a Ti bulk doped LiNi_(0.5−w)Mn_(1.5+w)−tTi_tO₄ phase and Ti-rich LiNi_0.5Mn_1.5−yTi_yO₄ segregates above 750 °C. Fourier-transform infrared spectrometry indicates increasing Ni–Mn ordering with annealing temperature, for both bare and surface modified LNMO. Ti surface modified LNMO annealed at 500 °C shows a superior cyclic stability, coulombic efficiency and rate performance compared to bare LNMO annealed at 500 °C when cycled at 3.4–4.9 V vs. Li/Li⁺. The improvements are probably due to suppressed Ni and Mn dissolution with Ti surface doping.

LiNi_0.5Mn_1.5O_4−δ surface is doped with Ti ion maintaining the spinel structure at 500 °C, higher annealing temperatures cause Ti diffusion from surface towards the core.

Clarification of some aspects related to genotoxicity assessment

The European Commission requested EFSA to provide advice on the following: (1) the suitability of the unscheduled DNA synthesis (UDS) in vivo assay to follow‐up positive results in in vitro gene mutation tests; (2) the adequacy to demonstrate target tissue exposure in in vivo studies, particularly in the mammalian erythrocyte micronucleus test; (3) the use of data in a weight‐of‐evidence approach to conclude on the genotoxic potential of substances and the consequent setting of health‐based guidance values. The Scientific Committee concluded that the first question should be addressed in both a retrospective and a prospective way: for future assessments, it is recommended no longer performing the UDS test. For re‐assessments, if the outcome of the UDS is negative, the reliability and significance of results should be carefully evaluated in a weight‐of‐evidence approach, before deciding whether more sensitive tests such as transgenic assay or in vivo comet assay would be needed to complete the assessment. Regarding the second question, the Scientific Committee concluded that it should be addressed in lines of evidence of bone marrow exposure: toxicity to the bone marrow in itself provides sufficient evidence to allow concluding on the validity of a negative outcome of a study. All other lines of evidence of target tissue exposure should be assessed within a weight‐of‐evidence approach. Regarding the third question, the Scientific Committee concluded that any available data that may assist in reducing the uncertainty in the assessment of the genotoxic potential of a substance should be taken into consideration. If the overall evaluation leaves no concerns for genotoxicity, health‐based guidance values may be established. However, if concerns for genotoxicity remain, establishing health‐based guidance values is not considered appropriate.

Early strength recovery after anterior cruciate ligament reconstruction using the fascia lata

INTRODUCTION

After undergoing anterior cruciate ligament (ACL) reconstruction, patients must recover at least 80% of their hamstring and quadriceps strength to be able to return to sports without risk to the graft. Harvesting of the patellar tendon leads to large deficits in quadriceps strength, while harvesting the hamstring tendons leads to large deficits in hamstring strength. However, there are no published studies on the strength deficit after ACL reconstruction with the fascia lata. The objective of this study was to evaluate the results of isokinetic testing in patients who underwent ACL reconstruction with a fascia lata graft and to analyze the individual factors affecting these results. The hypothesis was that preserving the quadriceps and hamstrings would lead to satisfactory isokinetic testing results by preserving the physiological balance between the flexor and extensor mechanisms in the leg.

MATERIALS AND METHODS

In this retrospective, single-center study, 53 patients had their quadriceps and hamstring strength recovery evaluated 6 months and 1 year post-ACL reconstruction by concentric isometric testing at a slow (90°/s) and fast velocity (240°/s). These results were analyzed as a function of individual characteristics such as age, sex, preinjury level and type of sports activity, and IKDC and Lysholm scores.

RESULTS

The quadriceps strength deficit at the slow and fast velocities was 27.5% and 22.5% at 6 months and 15.5% and 11% at 1 year, respectively. The hamstring strength deficit at the slow and fast velocities was 12.1% and 7% at 6 months and 8% and 6.4% at 1 year, respectively. The quadriceps to hamstring ratio at the slow and fast velocities was 66.7±16.5 and 71.3±15.5 at 6 months, and 61.1±14.9 and 67.6±12.5 at 1 year. Being less than 25 years of age, having a subjective IKDC grade or Lysholm score above 90, and being a professional athlete were significant predictors of better muscle strength recovery.

DISCUSSION

Isokinetic testing at 6 months and 1 year after ACL reconstruction surgery using the fascia lata showed that the quadriceps to hamstring ratio is close to physiological standards.

LEVEL OF EVIDENCE

IV retrospective study.

Toward High-Throughput Computational Screening of Carbon Nanotube Solvents

We use the corresponding distances method (CDM) to computationally assess the quality of 10 experimentally tested carbon nanotube (CNT) solvents. The CDM produces accurate and high-resolution potential of mean force curves from a single simulation per solvent. The method's very high efficiency allows us to investigate an unprecedented number of solvents in one study. The simulation results indicate that none of the tested molecules are solvents in the thermodynamic sense; instead, they are dispersants preventing reaggregation of already dispersed CNTs. We find that the dispersion free energy barrier correlates very well with the experimentally measured performance of the dispersants; i.e., the simulations place the solvents in the correct performance order. Our analysis of the structure-function relationship rationalizes this order.

A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc

A combined experimental and first-principles study is performed to study the origin of conductivity in ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR) and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide evidence for the fact that the formed complex of Al_Zn and Zn_i corresponds to the origin of the Knight shifted peak (KS) we observe in ²⁷Al NMR. As far as we know, the role of this complex has not been discussed in the literature to date. However, our first-principles calculations show that such a complex is indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly also form Zn clusters, leading to the observed increased conductivity.

Guidance on the use of the weight of evidence approach in scientific assessments

EFSA requested the Scientific Committee to develop a guidance document on the use of the weight of evidence approach in scientific assessments for use in all areas under EFSA's remit. The guidance document addresses the use of weight of evidence approaches in scientific assessments using both qualitative and quantitative approaches. Several case studies covering the various areas under EFSA's remit are annexed to the guidance document to illustrate the applicability of the proposed approach. Weight of evidence assessment is defined in this guidance as a process in which evidence is integrated to determine the relative support for possible answers to a question. This document considers the weight of evidence assessment as comprising three basic steps: (1) assembling the evidence into lines of evidence of similar type, (2) weighing the evidence, (3) integrating the evidence. The present document identifies reliability, relevance and consistency as three basic considerations for weighing evidence.

This publication is linked to the following EFSA Supporting Publications article: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2017.EN-1295/full

Guidance on the assessment of the biological relevance of data in scientific assessments

EFSA requested its Scientific Committee to prepare a guidance document providing generic issues and criteria to consider biological relevance, particularly when deciding on whether an observed effect is of biological relevance, i.e. is adverse (or shows a beneficial health effect) or not. The guidance document provides a general framework for establishing the biological relevance of observations at various stages of the assessment. Biological relevance is considered at three main stages related to the process of dealing with evidence: Development of the assessment strategy. In this context, specification of agents, effects, subjects and conditions in relation to the assessment question(s): Collection and extraction of data; Appraisal and integration of the relevance of the agents, subjects, effects and conditions, i.e. reviewing dimensions of biological relevance for each data set. A decision tree is developed to assist in the collection, identification and appraisal of relevant data for a given specific assessment question to be answered.

Ultrasonically spray coated silver layers from designed precursor inks for flexible electronics

Integration of electronic circuit components onto flexible materials such as plastic foils, paper and textiles is a key challenge for the development of future smart applications. Therefore, conductive metal features need to be deposited on temperature sensitive substrates in a fast and straightforward way. The feasibility of these emerging (nano-) electronic technologies depends on the availability of well-designed deposition techniques and on novel functional metal inks. As ultrasonic spray coating (USSC) is one of the most promising techniques to meet the above requirements, innovative metal organic decomposition (MOD) inks are designed to deposit silver features on plastic foils. Various amine ligands were screened and their influence on the ink stability and the characteristics of the resulting metal depositions were evaluated to determine the optimal formulation. Eventually, silver layers with excellent performance in terms of conductivity (15% bulk silver conductivity), stability, morphology and adhesion could be obtained, while operating in a very low temperature window of 70 °C-120 °C. Moreover, the optimal deposition conditions were determined via an in-depth analysis of the ultrasonically sprayed silver layers. Applying these tailored MOD inks, the USSC technique enabled smooth, semi-transparent silver layers with a tunable thickness on large areas without time-consuming additional sintering steps after deposition. Therefore, this novel combination of nanoparticle-free Ag-inks and the USSC process holds promise for high throughput deposition of highly conductive silver features on heat sensitive substrates and even 3D objects.

Guidance on the risk assessment of substances present in food intended for infants below 16 weeks of age

Following a request from the European Commission to EFSA, the EFSA Scientific Committee (SC) prepared a guidance for the risk assessment of substances present in food intended for infants below 16 weeks of age. In its approach to develop this guidance, the EFSA SC took into account, among others, (i) an exposure assessment based on infant formula as the only source of nutrition; (ii) knowledge of organ development in human infants, including the development of the gut, metabolic and excretory capacities, the brain and brain barriers, the immune system, the endocrine and reproductive systems; (iii) the overall toxicological profile of the substance identified through the standard toxicological tests, including critical effects; (iv) the relevance for the human infant of the neonatal experimental animal models used. The EFSA SC notes that during the period from birth up to 16 weeks, infants are expected to be exclusively fed on breast milk and/or infant formula. The EFSA SC views this period as the time where health-based guidance values for the general population do not apply without further considerations. High infant formula consumption per body weight is derived from 95th percentile consumption. The first weeks of life is the time of the highest relative consumption on a body weight basis. Therefore, when performing an exposure assessment, the EFSA SC proposes to use the high consumption value of 260 mL/kg bw per day. A decision tree approach is proposed that enables a risk assessment of substances present in food intended for infants below 16 weeks of age. The additional information needed when testing substances present in food for infants below 16 weeks of age and the approach to be taken for the risk assessment are on a case-by-case basis, depending on whether the substance is added intentionally to food and is systemically available.

Scientific motivations and criteria to consider updating EFSA scientific assessments

EFSA is committed to assess and communicate the risks occurring in the food and feed chain from farm to fork and to provide other forms of scientific advice. This work, carried out by EFSA since its inception, has resulted in the adoption of thousands of scientific assessments. EFSA is obliged to re‐assess past assessments in specific regulatory contexts such as those on food and feed additives, active substances in plant protection products and genetically modified food and feed. In other sectors, the consideration for updating past EFSA scientific assessments is taken on an ad hoc basis mainly depending on specific requests by risk managers or on EFSA self‐tasking. If safety is potentially at stake in any area within EFSA's remit, the readiness to update past scientific assessments is important to keep EFSA at the forefront of science and to promote an effective risk assessment. Although this task might be very complex and resource demanding, it is fundamental to EFSA's mission. The present EFSA Scientific Committee opinion deals with scientific motivations and criteria to contribute to the timely updating of EFSA scientific assessments. It is recognised that the decision for updating should be agreed following careful consideration of all the relevant elements by the EFSA management, in collaboration with risk managers and stakeholders. The present opinion addresses the scientific approaches through which it would be possible for EFSA to increase the speed and effectiveness of the acquisition of new data, as well as, to improve the consequent evaluations to assess the relevance and reliability of new data in the context of contributing to the better definition of whether to update past scientific assessments.

Speed-Bridge arthroscopic reinsertion of tibial eminence fracture (complementary to the adjustable button fixation technique)

In comminuted fractures of the intercondyloid eminence of the tibial spine, the quality of the reduction and the arthroscopic fixation, notably adjustable suture button fixation, is sometimes disappointing with reduction defects of the anterior bone block. In the Speed-Bridge technique, the two traction sutures of the adjustable button fixation are replaced with two braided sutures of different colors. After the button is placed above the eminence, reduction is obtained by tightening the loop of the button. The accessory communitive fragments are then packed in the depression around the main fragment. A second row provides bone suturing for these accessory fragments; traction sutures of the button are attached anteromedially and laterally with knotless anchors to obtain a Speed-Bridge-type inverted-V bone suture. The Speed-Bridge arthroscopic reinsertion technique of the tibial eminence effectively completes the adjustable button bone suture technique for communitive fractures to obtain better reduction and good stability.

Cognitive-behaviour therapy for post-traumatic stress in schizophrenia. A randomized controlled trial

BACKGROUND

There is limited evidence for effective interventions in the treatment of post-traumatic stress symptoms within individuals diagnosed with schizophrenia. Clinicians have concerns about using exposure treatments with this patient group. The current trial was designed to evaluate a 16-session cognitive restructuring programme, without direct exposure, for the treatment of post-traumatic stress symptoms specifically within individuals diagnosed with schizophrenia.

METHOD

A multicentre randomized controlled single-blinded trial with assessments at 0 months, 6 months (post-treatment) and 12 months (follow-up) was conducted. A total of 61 participants diagnosed with schizophrenia and exhibiting post-traumatic stress symptoms were recruited. Those randomized to treatment were offered up to 16 sessions of cognitive-behaviour therapy (CBT, including psychoeducation, breathing training and cognitive restructuring) over a 6-month period, with the control group offered routine clinical services. The main outcome was blind rating of post-traumatic stress symptoms using the Clinician Administered PTSD Scale for Schizophrenia. Secondary outcomes were psychotic symptoms as measured by the Positive and Negative Symptom Scale and the Psychotic Symptom Rating Scale.

RESULTS

Both the treatment and control groups experienced a significant decrease in post-traumatic stress symptoms over time but there was no effect of the addition of CBT on either the primary or secondary outcomes.

CONCLUSIONS

The current trial did not demonstrate any effect in favour of CBT. Cognitive restructuring programmes may require further adaptation to promote emotional processing of traumatic memories within people diagnosed with a psychotic disorder.

Remarkable lowering in the synthesis temperature of LiMn2O4via citrate solution–gel synthesis facilitated by ethanol

Low temperature synthesis routes for cathode materials, such as LMO, are currently very important. Here, through an elaborate study on the chemistry behind the precursor and EtOH interaction, the thermal budget was drastically reduced at 250 °C.

Update: use of the benchmark dose approach in risk assessment

The Scientific Committee (SC) reconfirms that the benchmark dose (BMD) approach is a scientifically more advanced method compared to the NOAEL approach for deriving a Reference Point (RP). Most of the modifications made to the SC guidance of 2009 concern the section providing guidance on how to apply the BMD approach. Model averaging is recommended as the preferred method for calculating the BMD confidence interval, while acknowledging that the respective tools are still under development and may not be easily accessible to all. Therefore, selecting or rejecting models is still considered as a suboptimal alternative. The set of default models to be used for BMD analysis has been reviewed, and the Akaike information criterion (AIC) has been introduced instead of the log-likelihood to characterise the goodness of fit of different mathematical models to a dose-response data set. A flowchart has also been inserted in this update to guide the reader step-by-step when performing a BMD analysis, as well as a chapter on the distributional part of dose-response models and a template for reporting a BMD analysis in a complete and transparent manner. Finally, it is recommended to always report the BMD confidence interval rather than the value of the BMD. The lower bound (BMDL) is needed as a potential RP, and the upper bound (BMDU) is needed for establishing the BMDU/BMDL per ratio reflecting the uncertainty in the BMD estimate. This updated guidance does not call for a general re-evaluation of previous assessments where the NOAEL approach or the BMD approach as described in the 2009 SC guidance was used, in particular when the exposure is clearly smaller (e.g. more than one order of magnitude) than the health-based guidance value. Finally, the SC firmly reiterates to reconsider test guidelines given the expected wide application of the BMD approach.

Hippocampal Aβ expression, but not phosphorylated tau, predicts cognitive deficits following repeated peripheral poly I:C administration

Alzheimer's disease is marked by the accumulation of the amyloid-beta (Aβ) peptide, and increases in phosphorylation of the microtubule associated protein, tau. Changes in these proteins are considered responsible, in part, for the progressive neuronal degeneration and cognitive deficits seen in AD. We examined the effect of repeated consecutive peripheral poly I:C injections on cognitive deficits, central Aβ, and phosphorylated tau accumulation, following three treatment durations: 7, 14, and 21 days. Forty-eight hours after the final injection, animals were trained in a contextual fear-conditioning paradigm, and tested 24h later. Immediately after testing, the hippocampus was collected to quantify Aβ and phosphorylated tau accumulation. Results showed that, although poly I:C-induced Aβ was significantly elevated at all time points examined, poly I:C only disrupted cognition after 14 and 21 days of administration. Moreover, elevations in phosphorylated tau were not seen until the 14-day time point. Interestingly, phosphorylated tau expression then declined at the 21-day time point. Finally, we demonstrated that Aβ levels are a stronger predictor of cognitive dysfunction, explaining 37% of the variance, whereas phosphorylated tau levels only accounted for 0.2%. Taken together, these results support the hypothesis that inflammation-induced elevation in Aβ disrupts cognition, independently of phosphorylated tau, and suggest that long-term administration of poly I:C may provide a model to investigate the contribution of long-term inflammation toward the development of Alzheimer's-like pathology.

Protocol for a randomised controlled trial comparing aqueous with alcoholic chlorhexidine antisepsis for the prevention of superficial surgical site infection after minor surgery in general practice: the AVALANCHE trial

INTRODUCTION

Surgical site infection (SSI) after minor skin excisions has a significant impact on patient morbidity and healthcare resources. Skin antisepsis prior to surgical incision is used to prevent SSI, and is performed routinely worldwide. However, in spite of the routine use of skin antisepsis, there is no consensus regarding which antiseptic agents are most effective. The AVALANCHE trial will compare Aqueous Versus Alcoholic Antisepsis with Chlorhexidine for Skin Excisions.

METHODS AND ANALYSIS

The study design is a prospective, randomised controlled trial (RCT) with the aim of investigating the impact of two different antiseptic preparations on the incidence of superficial SSI in patients undergoing minor skin excisions. The intervention of 0.5% chlorhexidine gluconate (CHG) in 70% alcohol will be compared with that of 0.5% CHG in aqueous solution. The trial will be conducted in four Australian general practices over a 9-month period, with 920 participants to be recruited. Consecutive patients presenting for minor skin excisions will be eligible to participate. Randomisation will be on the level of the patient. The primary outcome is superficial SSI in the first 30 days following the excision. Secondary outcomes will be adverse effects, including anaphylaxis, skin irritation, contact dermatitis and rash and patterns of antibiotic resistance.

ETHICS AND DISSEMINATION

The study has been approved by the James Cook University Human Research Ethics Committee (HREC). Findings will be disseminated in conference presentations and journals and through online electronic media.

DISCUSSION

RCTs conducted in general practice differ from hospital-based projects in terms of feasibility, pragmatism and funding. The success of this trial will be cemented in the fact that the research question was established by a group of general practitioners who identified an interesting question which is relevant to their clinical practice and not answered by current evidence.

TRIAL REGISTRATION NUMBER

ACTRN12615001045505; Pre-results.

From liquid to thin film: colloidal suspensions for tungsten oxide as an electrode material for Li-ion batteries

Using a colloidal suspension, electrochemically active tungsten oxide thin films (150 nm) have been prepared via ultrasonic spray deposition using two different current collectors, namely TiN and Pt.