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Using a combination of optical and electrical measurements, we develop a model for metastable defects in Ag-alloyed Cu(In,Ga)Se2, one of the leading thin film photovoltaic materials. By controlling the pre-selenization conditions of the back contact prior to the growth of polycrystalline (Ag,Cu)(In,Ga)Se2 absorbers and subsequently exposing them to various stresses (light soaking and dark-heat), we explore the nature and role of metastable defects on the electro-optical and photovoltaic performance of high-efficiency solar cell materials and devices. Positron annihilation spectroscopy indicates that dark-heat exposure results in an increase in the concentration of the selenium–copper divacancy complex (VSe–VCu), attributed to depassivation of donor defects. Deep-level optical spectroscopy finds a corresponding increase of a defect at Ev + 0.98 eV, and deep-level transient spectroscopy suggests that this increase is accompanied by a decrease in the concentration of mid-bandgap recombination centers. Time-resolved photoluminescence excitation spectroscopy data are consistent with the presence of the VSe–VCu divacancy complex, which may act as a shallow trap for the minority carriers. Light-soaking experiments are consistent with the VSe–VCu optical cycle proposed by Lany and Zunger, resulting in the conversion of shallow traps into recombination states that limit the effective minority carrier recombination time (and the associated carrier diffusion length) and an increase in the doping density that limits carrier extraction in photovoltaic devices. [ABSTRACT FROM AUTHOR]

Abstract The photobleaching dynamics of a series of three organic photovoltaic (OPV) donor polymer blends with five different fullerenes are presented. The fullerenes studied include PC 60 BM and four perfluoroalkylfullerenes with relatively large electron affinities, namely C 60 (CF 3) 2 , C 60 (i- C 3 F 7) 2 , C 60 (CF 3) 4 , and C 60 (CF 3) 8. The donor polymers were all based on cyclopentadithiophene (CPDT) and thienopyrrolodione (TPD), but the TPD side chains were designed to include alkyl, partially fluorinated alkyl, and fluorinated phenyl groups to improve miscibility of the active layer components. Exciton harvesting was probed with photoluminescence quenching measurements. Accelerated photodegradation studies of polymer:fullerene blends were then carried out under white light illumination at ∼1.2 suns in air. A strong correlation was observed between the polymer donor photobleaching rate and the electron affinity of the fullerene. The most dramatic effect was observed for a blend of C 60 (CF 3) 8 with the donor containing fluorinated phenyl groups: the blend required 150 times the dosing of photons to bleach to 80% of its initial optical density than an analagous blend of PC 60 BM and non-fluorinated donor polymer. These results ultimately suggest that appropriate fluorination strategies applied to both the donor and acceptor can be a viable route toward a new paradigm of intrinsically photo- and phase-stable OPV active layers. Graphical abstract Image 1 Highlights • Photodegradation studied in 15 partially fluorinated polymer:fullerene blends. • Electron affinity and miscibility of fullerene strongly influenced blend stability. • Photostability of select fluorinated blends improved by as much as a factor of 150. [ABSTRACT FROM AUTHOR]

Background: Fluid administration to critically ill patients remains the subject of considerable controversy. While intravenous fluid given for resuscitation may be life-saving, a positive fluid balance over time is associated with worse outcomes in critical illness. The aim of this systematic review is to summarise the existing evidence regarding the relationship between fluid administration or balance and clinically important patient outcomes in critical illness. Methods: We will search Medline, EMBASE, the Cochrane Central Register of Controlled Trials from 1980 to the present and key conference proceedings from 2009 to the present. We will include studies of critically ill adults and children with acute respiratory distress syndrome (ARDS), sepsis and systemic inflammatory response syndrome (SIRS). We will include randomised controlled trials comparing two or more fluid regimens of different volumes of fluid and observational studies reporting the relationship between volume of fluid administered or fluid balance and outcomes including mortality, lengths of intensive care unit and hospital stay and organ dysfunction. Two independent reviewers will assess articles for eligibility, data extraction and quality appraisal. We will conduct a narrative and/or meta-analysis as appropriate. Discussion: While fluid management has been extensively studied and discussed in the critical care literature, no systematic review has attempted to summarise the evidence for post-resuscitation fluid strategies in critical illness. Results of the proposed systematic review will inform practice and the design of future clinical trials. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotube (SWCNT)-fullerene (C60) bilayers represent an attractive "donor-acceptor" binary system for solar photoconversion, where the kinetics of photoinduced processes depend critically on the properties of the interface between the two materials. Using photoconductivity measurements we identify the kinetic scheme that describes the free carrier kinetics in such bilayers where the dominant SWCNT species is the (7,5) semiconducting nanotube. Following charge separation, the carrier kinetics, covering up tofour orders of magnitude in volumetric hole density, are described by a recombination process that is limited by capture and emission at traps or states at the SWCNT-C60 interface. The high-frequency mobility of holes in the (7,5) SWCNT phase is lower than in multichiral films, potentially due to differences in SWCNT defect density for nanotubes that have been purified more aggressively. The results obtained here provide fundamental insights into the transport and recombination of both charges and excitons within SWCNT thin films and bilayers, and point to several potential ways to improve SWCNT-C60 photovoltaic devices. [ABSTRACT FROM AUTHOR]

Objective To investigate the sevoflurane concentrations produced within the Stephens anaesthetic machine circuit (vaporizer in-circle system) at different fresh gas flow rates ( FGFRs), temperatures, vaporizer settings and vaporizer sleeve positions when used to anaesthetize dogs of different body sizes. Study design Experimental non-blinded studies. Animals Eighteen mixed breed dogs, weights 4-39 kg. Methods Anaesthetic induction with propofol was followed by maintenance with sevoflurane in oxygen via the Stephens anaesthetic machine. In study 1, the vaporizer setting, temperature and circuit FGFRs were altered with the vaporizer sleeve down ( n = 3), or in separate experiments, up ( n = 3). Delivered ( F i′ SEVO) and expired sevoflurane concentrations were recorded. Study 2 determined the vaporizer settings (sleeve up) required to achieve predetermined multiples of minimal alveolar concentration ( MAC) of F i′ SEVO when sevoflurane was delivered to dogs ( n = 12) of different bodyweights and at different FGFRs. Results Delivered concentrations of sevoflurane were sufficient to maintain anaesthesia in all dogs, regardless of bodyweight, FGFR, vaporizer temperature and sleeve position. F i′ SEVO increased with increasing temperature, when the vaporizer sleeve was down, when vaporizer setting was increased and when FGFR was decreased. As the FGFR increased or the dog's bodyweight decreased, higher vaporizer settings were required to produce the same F i′ SEVO. The median Stephens vaporizer settings to achieve an F i′ SEVO of 1.3 MAC ranged from 4.3 to 5.0 for a small dog (1-10 kg), 2.5 to 5.6 for a medium dog (15-25 kg) and 2.5 to 3.5 for a large dog (30-40 kg), depending on the FGFR. Conclusion and clinical relevance The Stephens anaesthetic machine can deliver to dogs, weighing 4 kg and above, concentrations of sevoflurane sufficient or in excess of that required to maintain anaesthesia, at temperatures from 10 to 35 °C, FGFRs of 1 to 5 times the patient's estimated metabolic oxygen requirement and at any vaporizer sleeve position. [ABSTRACT FROM AUTHOR]

Abstract: The development of new acceptor materials has played an important role in advancing the efficiency of organic photovoltaics (OPV). In this review we survey two types of acceptors, fullerene derivatives and single-walled carbon nanotubes (SWCNTs). The former has been the most successful type of acceptor in OPV, while the latter is a new type of acceptor that has shown encouraging spectroscopic results but its implementation in efficient devices is work in progress. We present some of the essential properties of an OPV acceptor, and the main experimental methodology used to characterize the photoconductivity of an OPV active layer comprising a donor-acceptor blend. We then discuss different aspects of donor-acceptor blends, or bulk heterojunctions, with a polymer donor and a fullerene or SWCNT acceptor. We show the basic charge-generation and recombination properties of a prototypical polymer-fullerene system, and discuss the significance of the molecular structure of the fullerene in terms of the mixing of the two components and its effect on photocarrier dynamics. In the case of the fullerene acceptors we also compare to OPV device efficiency. We discuss the role of charge and energy transfer from the polymer in exciton quenching in polymer-SWCNT blends, and show that the former results in the generation of long-lived charge carriers, similar to observations in polymer-fullerene blends. We show that SWCNT enrichment, to yield samples with only a few percent of metallic SWCNTs results in an enhancement of the photoconductance and carrier lifetime in P3HT-SCWNT blends. We also discuss the role that SWCNT diameter plays on the driving force for carrier generation, and suggest that smaller SWCNTs may be critical for efficient OPV device performance. Finally, we discuss the implications of the results of the photoconductivity studies on OPV device performance, and outline future challenges and open questions pertaining to the optimization of acceptors in OPV. [Copyright &y& Elsevier]

Summary: Toxic shock syndrome (TSS) is an acute, multi-system, toxin-mediated illness, often resulting in multi-organ failure. It represents the most fulminant expression of a spectrum of diseases caused by toxin-producing strains of Staphylococcus aureus and Streptococcus pyogenes (group A streptococcus). The importance of Gram-positive organisms as pathogens is increasing, and TSS is likely to be underdiagnosed in patients with staphylococcal or group A streptococcal infection who present with shock. TSS results from the ability of bacterial toxins to act as superantigens, stimulating immune-cell expansion and rampant cytokine expression in a manner that bypasses normal MHC-restricted antigen processing. A repetitive cycle of cell stimulation and cytokine release results in a cytokine avalanche that causes tissue damage, disseminated intravascular coagulation, and organ dysfunction. Specific therapy focuses on early identification of the illness, source control, and administration on antimicrobial agents including drugs capable of suppressing toxin production (eg, clindamycin, linezolid). Intravenous immunoglobulin has the potential to neutralise superantigen and to mitigate subsequent tissue damage. [Copyright &y& Elsevier]

A letter to the editor and a response by Christiane S. Hartog and Konrad Reinhart to the letter about their article "Renal Effects of Synthetic Colloids and Crystalloids in Patients With Severe Sepsis: A Prospective Sequential Comparison" in a 2011 are presented.

We report low-temperature electron transport behavior of trench-isolated silicon--germanium (SiGe) double quantum dots. By sweeping the potentials on side gates, we find a hexagonal charging diagram in the conductance measurements. It is also found that the gates allow the parameters of individual tunnel barriers to be changed over a wide range. Charging effects may therefore be observed in different coupling regimes, for example, the two dots that comprise the double dot can be induced to merge together yielding a large single dot. [ABSTRACT FROM AUTHOR]

Heat is an abundant but often wasted source of energy. Thus, harvesting just a portion of this tremendous amount of energy holds significant promise for a more sustainable society. While traditional solid-state inorganic semiconductors have dominated the research stage on thermal-to-electrical energy conversion, carbon-based semiconductors have recently attracted a great deal of attention as potential thermoelectric materials for low-temperature energy harvesting, primarily driven by the high abundance of their atomic elements, ease of processing/manufacturing, and intrinsically low thermal conductivity. This quest for new materials has resulted in the discovery of several new kinds of thermoelectric materials and concepts capable of converting a heat flux into an electrical current by means of various types of particles transporting the electric charge: (i) electrons, (ii) ions, and (iii) redox molecules. This has contributed to expanding the applications envisaged for thermoelectric materials far beyond simple conversion of heat into electricity. This is the motivation behind this review. This work is divided in three sections. In the first section, we present the basic principle of the thermoelectric effects when the particles transporting the electric charge are electrons, ions, and redox molecules and describe the conceptual differences between the three thermodiffusion phenomena. In the second section, we review the efforts made on developing devices exploiting these three effects and give a thorough understanding of what limits their performance. In the third section, we review the state-of-the-art thermoelectric materials investigated so far and provide a comprehensive understanding of what limits charge and energy transport in each of these classes of materials. [ABSTRACT FROM AUTHOR]

The article presents a study which shows how the encapsulation properties of the tpip moiety coupled with the advantages afforded by fluorination lead to dramatic improvements in the PL properties of Er3+-based organolanthanide complexes. A new bidentate chelating ligand, tetrapentafluorophenylimidodiphosphinate (HF-tpip), has been synthesized, first by preparing the appropriate fluorinated phosphine precursor, followed by coupling this to hexamethyldisilazane. It would appear that eliminating all of the C-H bonds serves to significantly reduce the degree of vibrational quenching, which in turn leads to longer lived Er3+ excited states and enhanced emission intensity.

Stablenitroxide radical bearing organic polymer materials areattracting much attention for their application as next generationenergy storage materials. A greater understanding of the inherentcharge transfer mechanisms in such systems will ultimately be paramountto further advancements in the understanding of both intrafilm andinterfacial ion- and electron-transfer reactions. This work is focusedon advancing the fundamental understanding of these dynamic chargetransfer properties by exploiting the fact that these species areefficient fluorescence quenchers. We systematically incorporated fluorescentperylene dyes into solutions containing the 2,2,6,6-tetramethylpiperidine-N-oxyl(TEMPO) radical and controlled their interaction by binding the TEMPOmoiety into macromolecules with varying morphologies (e.g., chainlength, density of radical pendant groups). In the case of the modelcompound, 4-oxo-TEMPO, quenching of the perylene excited state wasfound to be dominated by a dynamic (collisional) process, with a contributionfrom an apparent static process that is described by an ∼2nm quenching sphere of action. When we incorporated the TEMPO unitinto a macromolecule, the quenching behavior was altered significantly.The results can be described by using two models: (A) a collisionalquenching process that becomes less efficient, presumably due to areduction in the diffusion constant of the quenching entity, witha quenching sphere of action similar to 4-oxo-TEMPO or (B) a collisionalquenching process that becomes more efficient as the radius of interactiongrows larger with increasing oligomer length. This is the first studythat definitively illustrates that fluorophore quenching by a polymersystem cannot be explained using merely a classical Stern–Volmerapproach but rather necessitates a more complex model. [ABSTRACT FROM AUTHOR]

We report electrical measurements of a single arsenic dopant atom in the tunnel barrier of a silicon single-electron transistor (SET). In addition to performing the electrical characterization of the individual dopant, we study the series electrical transport through the dopant and SET. We measure the triple points of this hybrid double-dot, using simulations to support our results, and show that we can tune the electrostatic coupling between the two sub-systems. [ABSTRACT FROM AUTHOR]

We describe a comprehensive model for the optical properties of pristine films of poly-(3-hexylthiophene) (P3HT). The presented model is anisotropic with the optical axis normal to the substrate plane, which is consistent with previous x-ray diffraction studies that show preferential edge-on packing of the polymer chains on the substrate. Peak locations and spacings are defined using a Huang-Rhys vibronic progression consistent with known phonon energies. We demonstrate that the model fits variable-angle spectroscopic ellipsometry and normal-incidence transmission data well, and accurately predicts angle- and polarization-dependent transmission and reflection data. The spectral features of the optical constants used in the model are in excellent agreement with published spectroscopic data on P3HT. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010 [ABSTRACT FROM AUTHOR]

Purpose: Fluid overload is common in critical illness and is associated with mortality. This study investigated the feasibility of a randomised trial comparing conservative fluid administration and deresuscitation (active removal of accumulated fluid using diuretics or ultrafiltration) with usual care in critical illness. Methods: Open-label, parallel-group, allocation-concealed randomised clinical feasibility trial. Mechanically ventilated adult patients expected to require critical care beyond the next calendar day were enrolled between 24 and 48 h following admission to the intensive care unit (ICU). Patients were randomised to either a 2-stage fluid strategy comprising conservative fluid administration and, if fluid overload was present, active deresuscitation, or usual care. The primary endpoint was fluid balance in the 24 h up to the start of study day 3. Secondary endpoints included cumulative fluid balance, mortality, and duration of mechanical ventilation. Results: One hundred and eighty patients were randomised. After withdrawal of 1 patient, 89 patients assigned to the intervention were compared with 90 patients assigned to the usual care group. The mean plus standard deviation (SD) 24-h fluid balance up to study day 3 was lower in the intervention group (− 840 ± 1746 mL) than the usual care group (+ 130 ± 1401 mL; P < 0.01). Cumulative fluid balance was lower in the intervention group at days 3 and 5. Overall, clinical outcomes did not differ significantly between the two groups, although the point estimate for 30-day mortality favoured the usual care group [intervention arm: 19 of 90 (21.6%) versus usual care: 14 of 89 (15.6%), P = 0.32]. Baseline imbalances between groups and lack of statistical power limit interpretation of clinical outcomes. Conclusions: A strategy of conservative fluid administration and active deresuscitation is feasible, reduces fluid balance compared with usual care, and may cause benefit or harm. In view of wide variations in contemporary clinical practice, large, adequately powered trials investigating the clinical effectiveness of conservative fluid strategies in critically ill patients are warranted. [ABSTRACT FROM AUTHOR]

Carbon laser‐patterning (CLaP) is emerging as a new tool for the precise and selective synthesis of functional carbon‐based materials for on‐chip applications. The aim of this work is to demonstrate the applicability of laser‐patterned nitrogen‐doped carbon (LP‐NC) for resistive gas‐sensing applications. Films of pre‐carbonized organic nanoparticles on polyethylenetherephthalate are carbonized with a CO2‐laser. Upon laser‐irradiation a compositional and morphological gradient in the films is generated with a carbon content of 92% near the top surface. The specific surface areas of the LP‐NC are increased by introducing sodium iodide (NaI) as a porogen. Electronic conductivity and surface area measurements corroborate the deeper penetration of the laser‐energy into the film in the presence of NaI. Furthermore, impregnation of LP‐NC with MoC1−x (<10 nm) nanoparticles is achieved by addition of ammonium heptamolybdate into the precursor film. The resulting doping‐sensitive nano‐grain boundaries between p‐type carbon and metallic MoC1−x lead to an improvement of the volatile organic compounds sensing response of ΔR/R0 = −3.7% or −0.8% for 1250 ppm acetone or 900 ppm toluene at room temperature, respectively, which is competitive with carbon‐based sensor materials. Further advances in sensitivity and in situ functionalization are expected to make CLaP a useful method for printing selective sensor arrays. [ABSTRACT FROM AUTHOR]

The approaching end of Moore's law scaling has significantly accelerated multiple fields of research including neuromorphic-, quantum-, and photonic computing, each of which possesses unique benefits unobtained through conventional binary computers. One of the most compelling arguments for neuromorphic computing systems is power consumption, noting that computations made in the human brain are approximately 106 times more efficient than conventional CMOS logic. This review article focuses on the materials science and physical mechanisms found in metal chalcogenides that are currently being explored for use in neuromorphic applications. We begin by reviewing the key biological signal generation and transduction mechanisms within neuronal components of mammalian brains and subsequently compare with observed experimental measurements in chalcogenides. With robustness and energy efficiency in mind, we will focus on short-range mechanisms such as structural phase changes and correlated electron systems that can be driven by low-energy stimuli, such as temperature or electric field. We aim to highlight fundamental materials research and existing gaps that need to be overcome to enable further integration or advancement of metal chalcogenides for neuromorphic systems. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) are attractive materials for next-generation energy-harvesting technologies, including thermoelectric generators, due to their tunable opto-electronic properties and high charge carrier mobilities. Controlling the Fermi level within these unique 1D nanomaterials is often afforded by charge transfer interactions between SWCNTs and electron or hole accepting species. Conventional methods to dope SWCNT networks typically involve the diffusion of molecular redox dopant species into solid-state thin films, but solution-phase doping could potentially provide routes and/or benefits for charge carrier transport, scalability, and stability. Here, we develop a methodology for solution-phase doping of polymer-wrapped, highly enriched semiconducting SWCNTs using a p-type charge transfer dopant, F4TCNQ. This allows doped SWCNT inks to be cast into thin films without the need for additional post-deposition doping treatments. We demonstrate that the introduction of the dopant at varying stages of the SWCNT dispersion process impacts the ultimate thermoelectric performance and observe that the dopant alters the polymer selectivity for semiconducting vs metallic SWCNTs. In contrast to dense semiconducting polymer films, where solution-phase doping typically leads to disrupted morphologies and poorer TE performance than solid-state doping, thin films of solution-doped s-SWCNTs perform similarly to their solid-state doped counterparts. Interestingly, our results also suggest that solution-phase F4TCNQ doping leads to fully ionized and dimerized F4TCNQ anions in solid-state films that are not observed in films doped with F4TCNQ after deposition. Our results provide a framework for the application of solution-phase doping to a broad array of high-performance SWCNT-based thermoelectric materials and devices that may require high-throughput deposition techniques. [ABSTRACT FROM AUTHOR]

The denominator for 180-day mortality was incorrectly calculated, leading to an erroneously high percentage mortality in both treatment arms being reported in Table 2 (Outcomes). B Correction: Intensive Care Medicine (2022) 48:190-200 b https://doi.org/10.1007/s00134-021-06596-8 In the original article, there were some errors in the reporting of results: 1. [Extracted from the article]

Objectives: To characterize current practice in fluid administration and deresuscitation (removal of fluid using diuretics or renal replacement therapy), the relationship between fluid balance, deresuscitative measures, and outcomes and to identify risk factors for positive fluid balance in critical illness.Design: Retrospective cohort study.Setting: Ten ICUs in the United Kingdom and Canada.Patients: Adults receiving invasive mechanical ventilation for a minimum of 24 hours.Interventions: None.Measurements and Main Results: Four-hundred patients were included. Positive cumulative fluid balance (fluid input greater than output) occurred in 87.3%: the largest contributions to fluid input were from medications and maintenance fluids rather than resuscitative IV fluids. In a multivariate logistic regression model, fluid balance on day 3 was an independent risk factor for 30-day mortality (odds ratio 1.26/L [95% CI, 1.07-1.46]), whereas negative fluid balance achieved in the context of deresuscitative measures was associated with lower mortality. Independent predictors of greater fluid balance included treatment in a Canadian site.Conclusions: Fluid balance is a practice-dependent and potentially modifiable risk factor for adverse outcomes in critical illness. Negative fluid balance achieved with deresuscitation on day 3 of ICU stay is associated with improved patient outcomes. Minimization of day 3 fluid balance by limiting maintenance fluid intake and drug diluents, and using deresuscitative measures, represents a potentially beneficial therapeutic strategy which merits investigation in randomized trials. [ABSTRACT FROM AUTHOR]

The study of thermoelectric materials spans condensed matter physics, materials science and engineering, and solid-state chemistry. The diversity of the participants and the inherent complexity of the topic mean that it is difficult, if not impossible, for a researcher to be fluent in all aspects of the field. This review, which grew out of a one-week summer school for graduate students, aims to provide an introduction and practical guidance for selected conceptual, synthetic, and characterization approaches and to craft a common umbrella of language, theory, and experimental practice for those engaged in the field of thermoelectric materials. This review does not attempt to cover all major aspects of thermoelectric materials research or review state-of-the-art thermoelectric materials. Rather, the topics discussed herein reflect the expertise and experience of the authors. We begin by discussing a universal approach to modeling electronic transport using Landauer theory. The core sections of the review are focused on bulk inorganic materials and include a discussion of effective strategies for powder and single crystal synthesis, the use of national synchrotron sources to characterize crystalline materials, error analysis, and modeling of transport data using an effective mass model, and characterization of phonon behavior using inelastic neutron scattering and ultrasonic speed of sound measurements. The final core section discusses the challenges faced when synthesizing carbon-based samples and the measuring or interpretation of their transport properties. We conclude this review with a brief discussion of some of the grand challenges and opportunities that remain to be addressed in the study of thermoelectrics. [ABSTRACT FROM AUTHOR]

Background: It is unknown whether a conservative approach to fluid administration or deresuscitation (active removal of fluid using diuretics or renal replacement therapy) is beneficial following haemodynamic stabilisation of critically ill patients.Purpose: To evaluate the efficacy and safety of conservative or deresuscitative fluid strategies in adults and children with acute respiratory distress syndrome (ARDS), sepsis or systemic inflammatory response syndrome (SIRS) in the post-resuscitation phase of critical illness.Methods: We searched Medline, EMBASE and the Cochrane central register of controlled trials from 1980 to June 2016, and manually reviewed relevant conference proceedings from 2009 to the present. Two reviewers independently assessed search results for inclusion and undertook data extraction and quality appraisal. We included randomised trials comparing fluid regimens with differing fluid balances between groups, and observational studies investigating the relationship between fluid balance and clinical outcomes.Results: Forty-nine studies met the inclusion criteria. Marked clinical heterogeneity was evident. In a meta-analysis of 11 randomised trials (2051 patients) using a random-effects model, we found no significant difference in mortality with conservative or deresuscitative strategies compared with a liberal strategy or usual care [pooled risk ratio (RR) 0.92, 95 % confidence interval (CI) 0.82-1.02, I 2 = 0 %]. A conservative or deresuscitative strategy resulted in increased ventilator-free days (mean difference 1.82 days, 95 % CI 0.53-3.10, I 2 = 9 %) and reduced length of ICU stay (mean difference -1.88 days, 95 % CI -0.12 to -3.64, I 2 = 75 %) compared with a liberal strategy or standard care.Conclusions: In adults and children with ARDS, sepsis or SIRS, a conservative or deresuscitative fluid strategy results in an increased number of ventilator-free days and a decreased length of ICU stay compared with a liberal strategy or standard care. The effect on mortality remains uncertain. Large randomised trials are needed to determine optimal fluid strategies in critical illness. [ABSTRACT FROM AUTHOR]

We introduce a simple methodology to integrate prefabricated nanostructured-electrodes in solution-processed organic photovoltaic (OPV) devices. The tailored “photonic electrode” nanostructure is used for light management in the device and for hole collection. This approach opens up new possibilities for designing photonically active structures that can enhance the absorption of sub-bandgap photons in the active layer. We discuss the design, fabrication and characterization of photonic electrodes, and the methodology for integrating them to OPV devices using a simple lamination technique. We demonstrate theoretically and experimentally that OPV devices using photonic electrodes show a factor of ca. 5 enhancement in external quantum efficiency (EQE) in the near infrared region. We use simulations to trace this observed efficiency enhancement to surface plasmon polariton modes in the nanostructure. [ABSTRACT FROM AUTHOR]

Quantum mechanical effects induced by the miniaturization of complementary metal-oxide-semiconductor (CMOS) technology hamper the performance and scalability prospects of field-effect transistors. However, those quantum effects, such as tunneling and coherence, can be harnessed to use existing CMOS technology for quantum information processing. Here, we report the observation of coherent charge oscillations in a double quantum dot formed in a silicon nanowire transistor detected via its dispersive interaction with a radio frequency resonant circuit coupled via the gate. Differential capacitance changes at the interdot charge transitions allow us to monitor the state of the system in the strong-driving regime where we observe the emergence of Landau-Zener-Stückelberg-Majorana interference on the phase response of the resonator. A theoretical analysis of the dispersive signal demonstrates that quantum and tunneling capacitance changes must be included to describe the qubit-resonator interaction. Furthermore, a Fourier analysis of the interference pattern reveals a charge coherence time, T2 ≈ 100 ps. Our results demonstrate charge coherent control and readout in a simple silicon transistor and open up the possibility to implement charge and spin qubits in existing CMOS technology. [ABSTRACT FROM AUTHOR]

We propose a novel hybrid single-electron device for reprogrammable low-power logic operations, the magnetic single-electron transistor (MSET). The device consists of an aluminium single-electron transistor with a GaMnAs magnetic back-gate. Changing between different logic gate functions is realized by reorienting the magnetic moments of the magnetic layer, which induces a voltage shift on the Coulomb blockade oscillations of the MSET. We show that we can arbitrarily reprogram the function of the device from an n-type SET for in-plane magnetization of the GaMnAs layer to p-type SET for out-of-plane magnetization orientation. Moreover, we demonstrate a set of reprogrammable Boolean gates and its logical complement at the single device level. Finally, we propose two sets of reconfigurable binary gates using combinations of two MSETs in a pull-down network. [ABSTRACT FROM AUTHOR]

Wepresent a combined experimental–theoretical demonstrationof the energy spectrum and exchange coupling of an isolated donorpair in a silicon nanotransistor. The molecular hybridization of theatomic orbitals leads to an enhancement of the one- and two-electronbinding energies and charging energy with respect to the single donorcase, a desirable feature for quantum electronic devices. Our hydrogenmolecule-like model based on a multivalley central-cell correctedeffective mass theory incorporating a full configuration interactiontreatment of the 2-electron spectrum matches the measured data foran arsenic diatomic molecule with interatomic distance R= 2.3 ± 0.5 nm. [ABSTRACT FROM AUTHOR]

A metallic double dot is measuredwith radio frequency reflectometry.Changes in the total electron number of the double dot are determinedvia single electron tunnelling contributions to the complex electricalimpedance. Electron counting experiments are performed by monitoringthe impedance, demonstrating operation of a single electron ammeterwithout the need for external charge detection. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel fabrication process to realize high density silicon based quantum dot devices with close proximity Al and Si gates on ultrathin silicon-on-insulator for spin qubit applications. Al gates surrounding a Si nanowire channel can adjust tunnelling barrier height electrically, while Si plunger side gates enable precise control of the quantum dots potential. This device is fabricated using a multi-layer electron beam lithography process that is fully compatible with metal oxide semiconductor technology. Low temperature electrical measurements and Coulomb oscillation characteristics have demonstrated the capability of this structure to electrostatically define two coupled single electron transistors, one to be used as a turnstile device and the other as an electrometer. [Copyright &y& Elsevier]