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The ability to form robust, optoelectronically responsive, and mechanically tunable hydrogels using facile processing is desirable for sensing, biomedical, and light-harvesting applications. We demonstrate that such a hydrogel can be formed using aqueous complexation between one conjugated and one nonconjugated polyelectrolyte. We show that the rheological properties of the hydrogel can be tuned using the regioregularity of the conjugated polyelectrolyte (CPE) backbone, leading to significantly different mesoscale gel morphologies. We also find that the exciton dynamics in the long-time limit reflect differences in the underlying electronic connectivity of the hydrogels as a function CPE regioregularity. The influence of excess small ions on the hydrogel structure and the exciton dynamics similarly depends on the regioregularity in a significant way. Finally, electrical impedance measurements lead us to infer that these hydrogels can act as mixed ionic/electronic conductors. We believe that such gels possess an attractive combination of physical-chemical properties that can be leveraged in multiple applications.

We used a vesicle scaffold to form a ternary, quasi-panchromatic funnel for electronic excited states oriented from the outer surface towards the membrane. We did so via electronic energy transfer (EET) from two conjugated polyelectrolytes to a phthalocyanine.

Introduction Early wound coverage remains one of the most essential variables influencing survival of extensively burned patients, especially with a total burned surface area (TBSA) of more than 50%. In patients with limited donor sites, techniques such as e.g. the Meek micrograft procedure or cultured epidermal allografts have proven to be viable methods. In this systematic review (SR) and meta-analysis (MA) we studied the outcomes of different techniques for wound coverage in patients with massive burn injuries ≥50% TBSA within the last 17 years. Methods According to PRISMA guideline the medical databases PubMed, Cochrane, Embase, Web of Science Medical records were screened in 5 languages from 01/2005 until 01/2022 by three reviewers, independently. Inclusion criteria were prospective or retrospective studies on patients with massive burns of ≥50% TBSA. Results After a two-stage review process, 33 studies were identified for the SR and MA. Regions of publication were Asia (n=15), North America (n=8), Europe (n=7), Australia (n=3). In total, 1678 patients with a mean age of 31.4 ± 14.2 years were included. The male to female ratio was 2.25 : 1. Mean TBSA was 66,5 ± 12.2%. Methods of wound coverage consisted of Meek micrografts, cultured epithelial autografts and/or allografts. The mean length of stay was 76.5 ± 32.4 days. Initial graft-take was 78,0 ± 15.8%. Grafting techniques did neither substantially differ in the length of stay nor the healing rate. Conclusions In patients with massive burn injuries of ≥50% TBSA the length of stay and the healing rates were comparable between Meek micrograft procedure, cultured epithelial allografts and combined techniques. Applicability of Research to Practice Wound coverage by Meek micrograft procedure with expansion of up to 1:10 and a potential combination with cultured epithelial allografts should be considered early in patients with massive burn injury.

Yield reduction resulting from high temperatures and tipburn are common issues during the summer for hydroponically grown lettuce using the nutrient–film technique (NFT). We investigated the yield and degree of tipburn of lettuce ‘Red Butter’, ‘Green Butter’, and ‘Red Oakleaf’ of the Salanova® series under different-solution electrical conductivity (EC) and pH levels. We also quantified the effect of foliar spray application of calcium chloride (CaCl2) on the yield and degree of tipburn using the lettuce cultivar Green Butter. For the EC experiment, the plants were grown at four EC levels (1.4, 1.6, 1.8, or 2.0 mS·cm–1) and a constant pH of 5.8. For the pH experiment, the plants were grown at and four pH levels (5.8, 6.0, 6.2, or 6.4) and a constant EC of 1.8 mS·cm–1. For the foliar spray experiment, CaCl2 was applied 1 week after transplanting into NFT channels at three different concentrations: 0, 200, 400, or 800 mg·L calcium (Ca). During the EC trial, the maximum yields were observed at or more than 1.8 mS·cm–1 for ‘Green Butter’ (263 ± 14 g/head) and ‘Red Butter’ (202 ± 8 g), and more than 1.6 mS·cm–1 for ‘Red Oakleaf’ (183 ± 6 g). The yield of ‘Green Butter’ was 75 g less at 1.4 mS·cm–1 compared with 1.8 mS·cm–1. Tipburn symptoms were less at 1.4 mS·cm–1 for ‘Green Butter’ whereas other cultivars were not highly susceptible. In pH trials, the maximum yield for all cultivars was found at pH 6.0 and 6.2. There were no differences in tipburn symptoms among all pH levels. The foliar spray treatment, twice a week at 400 or 800 mg·L–1 Ca, provided improved tipburn control, as the tipburn symptoms were minimal and the impact on yield was minor compared with reducing EC. This series of experiments found evidence in proper EC and pH management for optimum yield and tipburn control in NFT lettuce grown in summer conditions.

The article has two aims: firstly, it provides a holistic account of Zygmunt Bauman’s oeuvre, and secondly, it presents an extensive up-to-date and multilingual bibliography of his published writings. The authors discuss Bauman’s prolificacy, as well as the stylistic, formal and substantive heterogeneity of his work. Taking this into account, they reflect on the curious reception of his oeuvre in the wider disciplinary field of sociology. The bibliography attached to the paper provides the most complete account of Bauman’s writings. Building on previous bibliographies, and drawing on archival research in the Janina and Zygmunt Bauman Papers at the University of Leeds, the bibliography spans 63 years from his first publication to his most recent. Many of these papers – both in English and Polish – are presented for the first time in the list of his works.

Silicon nanoparticles have emerged as a promising alternative to graphite to improve the energy density of next-generation lithium-ion battery anodes. Nano-sized Si domains facilitate rapid ion transport and minimize particle-scale mechanical degradation, but also exhibit increased (electro)chemical reactivity with Li-ion electrolyte components due to their high surface area. We have previously demonstrated that surface modification of Si nanoparticles with pitch-carbon is an effective strategy to reduce these parasitic reactions. In the present work, we holistically evaluate the mechanistic contribution of pitch-carbon coating to the observed stability improvement over uncoated Si. We utilize coupled in situ and ex situ methods to probe changes to solid-surface, volatile headspace, and gas-phase chemistry occurring during initial cycling. Measurements taken at targeted potentials associated with electrolyte species reduction enables the decoupling of specific reaction pathways tied to interfacial stability. Further, we demonstrate the non-trivial role of gas reconsumption in dictating the nature of the passivating surface layer evolved on both uncoated and pitch-coated Si. This multi-phase analysis offers insights into the mechanism of effective surface passivation, which may be applied to inform future Si material development. Figure 1

Silicon-based anodes for Li-ion batteries (LIB) have the potential to increase the energy density over graphite-based LIB anodes. However, silicon anodes exhibit poor cycle and calendar lifetimes due to mechanical instabilities and high chemical reactivity with the carbonate-based electrolytes that are typically used in LIBs. In this work, we synthesize a pitch-carbon coated silicon nanoparticle composite active material for LIB anodes that exhibits reduced chemical reactivity with the carbonate electrolyte compared to an uncoated silicon anode. Silicon primary particle sizes Figure 1

This article elucidates some connections and divergences between S.N. Eisenstadt’s work on multiple modernities and critical reflections on ‘African modernity’ presented by Africanist scholars. It argues that there is more cross-over between these discussions than is commonly thought when both are seen as parallel responses to the shortcomings of post-war modernization theory. Eisenstadt’s work can inform debates in African Studies concerning the effective power of tradition in postcolonial African societies, and on African interpretations of the ‘cultural programme’ of modernity. The article also discusses some weaknesses in Eisenstadt’s theorizing which arise from an extension of the multiple modernities framework to African societies, namely, an underappreciation of the various modalities of colonial imperialism and racialization, as well as the institutional constraints placed on postcolonial societal elites. It claims that these can be offset via a dialogue with the work of scholars in African Studies. Moreover, it is argued that the paradigm of multiple modernities can more satisfactorily shed light on African trajectories of modernity via the retrieval of tenets of Eisenstadt’s ‘heterodox’ modernization theory and work on post-traditionality, outlined in the 1960s and the 1970s, which include specific reflections on African societies.

In the immediate aftermath of his death, a number of excellent articles were written that each provide a different door into the vast room of Bauman’s sociology. In the past year or so, there have also been a number of books that have set about providing a more ‘critical analysis’ of his work whilst also considering how sociology might look anew and move creatively ‘beyond Bauman’ (Blackshaw 2016; Jacobsen ed. 2016; Rattansi 2017). In so doing, these welcome contributions clearly take Bauman’s sociological imagination very seriously and provide useful reference points for both scholars and students seeking a more robust examination of Bauman’s ideas. Each contribution deserves to be read and studied as they provide new and considered insights into Bauman’s legacy for the social sciences and humanities. Throughout the article that follows, we make our own contribution to the curious reader’s deliberations on these debates by shining a light on those aspects of Bauman’s work that may have become somewhat hidden and possibly overlooked in what we see as a growing tendency to focus primarily upon his later writings on ‘liquid modernity’. We argue that in order to grasp fully the meaning of Bauman’s writing in the more popular post-2000 phase, it is vital that one understands these earlier foundations of his thought. In this way, we hope that we may go some way to rebalancing the concerns of some contemporary critics.

Understanding and controlling the topography of an abrasive, vitreous-bonded grinding wheel is important for optimising performance of the grinding process used to machine advanced aerospace materials. The dressing process plays a critical role in ensuring grinding wheel form and topography is achieved prior to grinding, however the mechanisms of roller dressing for advanced engineered grit morphologies is not well understood. In this investigation, the impact of different dressing parameters on the topography of two vitreous-bonded abrasive wheels with engineered grit morphologies and resulting grinding performance was assessed and compared to a grinding wheel with conventional ‘random’ grit morphology. Continuous dressing grinding cuts were performed under a range of dressing parameters (two different infeed rates and three speed ratios) to determine the impact of dressing condition on grit fracturing and influence of resulting varying wheel topographies, whilst controlling wheel breakdown (wheel self-sharpening during grinding cuts). Constant grinding parameters were used for all grinding cuts and power consumption was monitored during the process. The generated grinding wheel surface morphology was characterised by using a range of surface roughness/topography parameters. In line with previous studies for conventional grit morphologies, results for all three wheel morphologies studied show that under aggressive dressing conditions grinding power is reduced, but so is ground surface quality. Scanning Electron Microscopy imaging of abrasive wheel sections revealed changing grit fracture mechanisms under different dressing parameters. Significant variation in dressing response between conventional and engineered grit morphologies was also observed. This work aims to enhance the fundamental understanding of the relationship between wheel topography and grinding performance using experimental data, and could influence dressing strategies used in industry.

Vitreous-bonded grinding wheels are widely used for machining features on aerospace components achieving high material removal rates under high pressure coolant. Dressing is a vital stage in the grinding process to ensure a consistent wheel topography and performance. However, the effects of roller dressing on functional performance of vitreous grinding wheels as well as its influence on different abrasive grit morphologies have not been fully characterised. This paper studies the influence of dressing parameters on the topography, morphology and characteristics of the surface of different vitrified abrasive wheels in order to better understand the process and therefore optimise the preparation of grinding wheels for industrial machining. Alumina grinding wheels with conventional and engineered grit shapes were dressed at two different infeed rates over a range of seven different speed ratios (from −0.8 to +1). An experimental methodology has been developed incorporating a range of known techniques to define the abrasive wheel condition including measured power consumption and ground graphite coupons as well as using optical microscopes to measure grain fracture flats, peak density and abrasive grain shape. It has been found that power consumption of the grinding wheel spindle increases at higher infeed rates and speed ratios. This leads to increased fracturing of the grains and whole-grain pull out. According to the results the infeed rate has a more substantial effect on wheel topography than speed ratio and the response of engineered grit morphologies to dressing is dependent on grit orientation.

Nanoindentation was used to probe the local slip resistance in CP-Ti deformed in compression to different extents. Changes in hardness in the deformed grains and twins were compared with the change in flow stress measured during deformation, with the aim to elucidate the relative contribution of slip and twinning to the work hardening of Ti alloys. The hardness values were calibrated with measurements on binary Ti–Al alloys. The hardness increased only slightly with deformation and cannot explain the observed work hardening. Although twinned regions were found to be harder than the parent grains, this increase was found to be small once the effect of crystal orientation was accounted for. The increase in hardness in the twins was slightly higher for compressive twins than for tensile twins. It is proposed that this modest hardness increase in the twins is more consistent with the presence of twinning stresses than with a change in the local flow stress caused by dislocation interactions. The implications of these findings to the work hardening of CP titanium are discussed.

Next-generation electrodes for rechargeable lithium-ion batteries (LiBs) promise higher energy and power storage at lower cost. For example, silicon has a theoretical capacity approximately 10 times higher compared to current state-of-the-art anodes based on graphite, 3580 mAhg-1 vs 372 mAhg-1, respectively.1 On the other side of the cell, it has been shown that increasing the Ni content in cathodes based on lithium nickel manganese cobalt oxide (LiNi1-x-yMnxCoyO2 or NMC) increases their specific capacity up to 280 mAhg-1.2, 3. Unfortunately, the improvements in energy storage provided by these next-gen materials is currently offset by their rapid degradation due to the undesirable (electro)chemical reactions, taking place at electrode surface in contact with a reactive liquid organic electrolyte, which form the unstable electrode-electrolyte interphase (EEI).2, 4-8 Understanding the complex reactions taking place in each phase, as well as the compositional, morphological, and structural formation and evolution of the EEI is essential to the development of mitigation strategies enabling longer battery life. Over the decades of battery R&D, many spectroscopic and analytical techniques have been developed to characterize the properties of battery components and understand cell capacity fade, but most often, these techniques are applied ex situ to a component of the battery that has been harvested from a disassembled cell after testing.9, 10 While informative, ex situ measurements cannot elucidate changes happening to the cell during testing, thus potentially failing to provide critical information about correlated processes underpinning the cell performance. Here we present a summary of our recently-developed in situ Raman and FTIR spectroscopic techniques and in situ gas chromatography-mass spectrometry-flame-ionization detection (GC-MS-FID) analytical methods applied to custom battery cells under test11-13. By monitoring the EEI “in real-time” during cell charging and discharging cycles, we gain a better understanding of the critical mechanisms occurring near the electrode surfaces. For example, with our in situ FTIR spectroscopic methods, we have investigated the voltage dependent electrolyte solution structure changes at the interface, electrode changes correlated to redox chemistry, and the electrode/electrolyte interfacial layer evolution in LiBs employing high-Ni cathodes. In an electrochemical cell, gas evolution from electrolyte degradation is controlled by many factors, including the electrolyte’s physical and (electro)chemical properties, electrode compositions, and the applied stress to the cell (voltage, current, temperature, etc.), and we have used GC-MS-FID to elucidate mechanistic relationships between gas evolution/interface formation in novel Si-anode LiBs. Our various in situ cell designs provide both sensitive detection and reliable electrochemical device testing. Ultimately, we aim to develop in-situ gas analysis tools to be coupled with in situ spectroscopic techniques enabling a holistic understanding of the battery. References: K. Feng, M. Li, W. Liu, A. G. Kashkooli, X. Xiao, M. Cai, and Z. Chen, Small, 14 (8), 1702737 (2018). F. Schipper, E. M. Erickson, C. Erk, J.-Y. Shin, F. F. Chesneau, and D. Aurbach, Journal of The Electrochemical Society, 164 (1), A6220-A6228 (2017). N. Nitta, F. Wu, J. T. Lee, and G. Yushin, Materials Today, 18 (5), 252-264 (2015). J. Kasnatscheew, S. Röser, M. Börner, and M. Winter, ACS Applied Energy Materials, 2 (11), 7733-7737 (2019). M. Wetjen, D. Pritzl, R. Jung, S. Solchenbach, R. Ghadimi, and H. A. Gasteiger, Journal of The Electrochemical Society, 164 (12), A2840-A2852 (2017). J.-H. Kim, H.-H. Ryu, S. J. Kim, C. S. Yoon, and Y.-K. Sun, ACS Applied Materials & Interfaces, 11 (34), 30936-30942 (2019). H.-H. Ryu, K.-J. Park, C. S. Yoon, and Y.-K. Sun, Chemistry of Materials, 30 (3), 1155-1163 (2018). M. Ashuri, Q. He, and L. L. Shaw, Nanoscale, 8 (1), 74-103 (2016). A. M. Tripathi, W.-N. Su, and B. J. Hwang, Chemical Society Reviews, 47 (3), 736-851 (2018). P. B. Balbuena and Y. X. Wang, Lithium-ion Batteries: Solid-electrolyte Interphase, World Scientific Publishing Company (2004). B. J. Tremolet de Villers, Y. Ha, and S.-D. Han, in "236th ECS Meeting (October 13-17, 2019)". ECS, 2019. Y. Ha, B. J. Tremolet de Villers, Z. Li, Y. Xu, P. Stradins, A. Zakutayev, A. Burrell, and S. D. Han, J Phys Chem Lett, 11 (1), 286-291 (2020). B. Tremolet de Villers, S.-M. Bak, J. Yang, and S.-D. Han, Batteries & Supercaps, under revision (2020).

Due to inherent properties of the silicon (Si)-electrolyte interphase (SEI)—complexity, high reactivity and continuous evolution—it remains a poorly understood topic in advanced Si-based Li-ion battery (LiB) research,1,2 and its detailed and real-time analysis is a great challenge. Vibrational spectroscopy, such as Raman and Fourier-transform infrared spectroscopy (FTIR), is one of the most important analytical tools for understanding and quantifying the interfacial chemical reactions. These techniques are used extensively by the battery community in their ex situ form, but developing in situ variants of these techniques and combing in situ analyses from both techniques can provide new insight and help to elucidate the mechanism of interfacial failure in battery systems. We have optimized in situ vibrational spectroscopy methods that show reproducible and stable performance over multiple cycles in terms of both electrochemistry and spectroscopy, which enables us to monitor the surface chemistry and evolution of the SEI. This is essential to gaining a better understanding of the electrochemical performance of Si-based LiBs.3-5 Further, the reactions leading to SEI growth and evolution in Si-based LiBs may be more comprehensively probed by monitoring changes in the gas and liquid phases. To this end, we are developing novel in situ gas chromatography (GC) techniques, which may be applied to both coin-type cells and larger-format pouch cells. Using custom cell designs, we track the evolution of electrolyte and degradation species in the gaseous and liquid6 phases at various stages of battery cycling. We achieve both qualitative identification and quantification through coupled mass-spectrometry (MS) and flame ionization detection (FID). This GC-MS-FID analysis complements our in situ vibrational spectroscopy studies, providing a true multi-modal and multi-phase approach to SEI analysis. Taken together, these studies can provide an in-depth understanding of the underlying chemistry and physics and mechanical explanation of various reactions/interactions within the SEI, thus enabling the rational design of electrolytes and electrodes to stabilize the SEI. Additionally, we have developed advanced techniques to assess the structural and electronic properties of Si-based composite electrodes. Comprehensive characterization of pristine and cycled composite electrode architectures is complicated by several inherent properties. During battery operation, Si-based composite electrodes experience localized lithiation and reaction rates due to heterogeneous conditions and distributions of electrode components. Further, (electro)chemical and structural properties continuously evolve during cycling. Finally, the nanoscale diameter of particles falls beneath the lateral and depth resolution of most laboratory-based instruments. To address these challenges, we have utilized scanning spreading resistance microscopy (SSRM) to image the three-dimensional nanostructure of composite anodes via contrast in the electronic properties of the distinct components.7 Specifically, Si-based composite anode components, such as SiOx nanoparticles, graphite, carbon black, and lithium polyacrylate binder, are all readily distinguished by their intrinsic electronic properties, with measured electronic resistivity closely matching known material properties. In combination with scanning electron microscopy/energy dispersive X-ray (SEM-EDX) and electron energy loss spectroscopy (EELS), we expect to compare the electrical, chemical and structural changes of Si-based composite electrodes before and after cycling. This can provide a fundamental understanding of localized degradation mechanisms, which informs our understanding of SEI formation and evolution. This technique may also be applied to assess heterogeneous aging within the electrode, and is more broadly applicable to other battery systems. In particular, it may be used to better understand particle dispersion, localized lithiation, electrolyte-electrode interphase formation/evolution, and degradation processes in composite electrodes for the development of next-generation batteries. References: Xu, C. Stetson, K. Wood, E. Sivonxay, C. Jiang, G. Teeter, S. Pylypenko, S.-D. Han, K. A. Persson, A. Burrell and A. Zakutayev, ACS Appl. Mater. Interfaces 2018, 10, 38558-38564. -D. Han,* K. N. Wood, C. Stetson, A. G. Norman, M. T. Brumbach, J. Coyle, Y. Xu, S. P. Harvey, G. Teeter, A. Zakutayev and A. K. Burrell, ACS Appl. Mater. Interfaces 2019, 11, 46993-47002. Ha, B. J. Tremolet de Villers, Z. Li, Y. Xu, P. Stradins, A. Zakutayev, A. Burrell and S.-D. Han,* J. Phys. Chem. Lett. 2020, 11, 286-291. Yin, R. Pekarek, C. Stetson, M. Schnabel, E. Arca, S. Harvey, B. Tremolet de Villers, S.-D. Han, S. DeCaluwe, G. Teeter, C. Ban and N. Neale, 2021, under revision. J. Tremolet de Villers, J. Yang, S.-M. Bak and S.-D. Han,* 2021, under revision. Ha, C. Stetson, S. P. Harvey, G. Teeter, B. J. Tremolet de Villers, C.-S. Jiang, M. Schnabel, P. Stradins, A. Burrell and S.-D. Han,* ACS Appl. Mater. Interfaces 2020, 12, 49563-49573. C. Stetson, Z. Huey, A. Downard, Z. Li, B. To, A. Zakutayev, C.-S. Jiang, M. Al-Jassim, D. P. Finegan, S.-D. Han* and S. C. DeCaluwe, Nano Lett. 2020, 20, 8081-8088.

Background COPD exacerbations (eCOPD) deleteriously effects patient outcomes and healthcare spending. Emergency Department observation units (ED-Obs) provide short-term acute care in order to reduce resource utilisation, however successful COPD-specific programs in ED-Obs are lacking. Objectives Achieve 90% reliable implementation of COPD care-bundle among eCOPD patients discharged from ED-Obs by April 2017. The overall goal is to reduce 30 day all-cause ED revisits for eCOPD patients discharged from ED-Obs from the baseline rate of 49%. Methods Setting: An 800-bed academic hospital with 700 eCOPD ED encounters/year, out of which 20% triage to ED-Obs. All patients triaged to ED-Obs with eCOPD diagnosis were included. A five-element COPD bundle designed to mitigate system-level failures, was adopted from in-patient setting. The bundle components were: appropriate inhaler regimen, 30 day inhaler supply, personalised inhaler education, standardised discharge instructions and follow-up in 15 days. A multidisciplinary team was formed to support bundle implementation within the 24 hours ED-Obs stay using Model for Improvement. Bundle component adherence and 30 day ED revisit rates were monitored using SPC p-charts. Hospitalisation rate from ED-Obs was used as balancing measure. Results The patient characteristics were similar in baseline and post-bundle period. Multiple PDSA cycles were performed to achieve a final process (Figure 1). The adherence to COPD care bundle components has maintained >90% from 4/2017–8/2017 (Figure 2). The 30 day all-cause ED revisit rate reduced from 49% to 28% with a pending system-shift on SPC (Figure 3). Hospitalisation rate remained unchanged. Conclusions Improving care at discharge transition of eCOPD patients from ED-Obs to home through reliable adherence to COPD care-bundle reduces 30 day all-cause ED revisits.

Les besoins de l'industrie en traduction technique sont presentes a partir de l'exemple francais de la Societe Framatome. La place accordee dans cette societe aux traducteurs, essentiellement anglophones, est analysee ainsi que le role qu'ils jouent dans les transferts de technologie