bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy level tuning at the interface of inorganic and organic semiconductors
Authors: McConnon Aili
Published: December 2021

Optimizing the functionality of semiconductor heterojunctions
Preliminary experimental investigation on small-aspect-ratio cylindrical solid liner implosion using compact pulsed power generator
Authors: Zhang Xuping , Shui Rongjie , Xu Chao , Wu Gang , Chen Xuemiao , Wang Guiji , Luo Binqiang , Tan Fuli , Zhao Jianheng , Sun Chengwei , Liu Cangli
Published: December 2021

Small-aspect-ratio cylindrical liner implosion on timescales of the order of hundreds of nanoseconds is important in the fields of high-energy-density physics, implosion dynamics, and inertial confinement fusion. This paper describes the design and development of a cylindrical liner load that has a low inductance and uniform magnetic field and its application in the CQ7 compact pulsed power generator. The dynamic response properties and implosion symmetry of liners with aspect ratios ranging from 5 to 9 are investigated. The experimental results show that the azimuthal symmetry of the liner remains intact, and that a liner with an inner diameter of 6.2 mm and a thickness of 0.4 mm can be accelerated up to 10 km/s before the reflected beam is lost. The demonstrated high performance of the experimental technique used for imploding the liner could be beneficial for studying the implosion and dynamics of materials on compact pulse power generators in the future.
Pressure-induced phase transition and electrical properties of yttrium-doped polycrystalline BaTiO3
Authors: Luo Xiaosong , Wu Lei , Huang Jinbao , Zhou Mei
Published: December 2021

The electrical transport properties of undoped and 2% yttrium-doped polycrystalline BaTiO3 (BTY0 and BTY2) at high temperature and high pressure were studied using a diamond-anvil cell in conjunction with AC impedance spectroscopy up to ∼20 GPa. The BTY0 endured a ferroelectric–paraelectric transition at ∼5 GPa, and a ∼2 GPa ahead of the transition point was observed in BTY2. We found that the doping of 2% Y ions in BTY2 leads to a decrease in the Curie transition temperature. For both BTY0 and BTY2, an increase in pressure will result in a significant reduction in the Curie temperature and the decreasing rate gradually decreased under pressure. The reducing grain size of the sample and the effect of the deviatoric stresses are considered as the main factors causing the decrease of dTC/dP.
Nitrogen diffusion in zinc oxide
Authors: Nickel N. H. , Gluba M. A.
Published: December 2021

Nitrogen migration in ZnO was investigated by nitrogen isotope diffusion. The samples were deposited using plasma-assisted pulsed laser deposition. Nitrogen concentration depth profiles were obtained from secondary-ion-mass spectrometry measurements, and in gas effusion measurements, the molecular nitrogen flux was measured as a function of the heating rate. Measurements performed on sample stacks that were doped with isotopically enriched 15N and 14N in the top and bottom half of the samples, respectively, clearly demonstrate that nitrogen diffusion is governed by atomic diffusion and molecules are formed primarily at the sample surface. At high nitrogen concentrations, the diffusion coefficient, D, is thermally activated, while for low concentration diffusion, D is independent of temperature. The data can be described by a model, where N diffusion occurs between minimum energy positions by surmounting the barrier between sites at a saddle point. Separated in energy from the transport sites are deep levels with a concentration of ≈1018 cm−3. For high-concentration diffusion, the N chemical potential, μN, resides at ≈1.36 eV below the migration saddle point. For low concentration diffusion, μN shifts deeper in energy with a rate of ≈2.8 meV/K as the temperature increases. From N effusion data, the nitrogen density-of-states is derived. For high N concentration diffusion, two peaks are observed at ES–μN = −0.93 and −1.26 eV, while for low N concentration diffusion, a prominent peak at ES–μN = −1.63 eV occurs. Applying density functional theory calculations, different microscopic diffusion mechanisms are evaluated, and the corresponding transition states are derived.
p-type c-Si/SnO2/Mg heterojunction solar cells with an induced inversion layer
Authors: Wang Qi , Zhou Yurong , Guo Wanwu , Yang Ying , Shang Jiacheng , Chen Hu , Mao Haibo , Zhu Tianyu , Zhou Yuqin , Liu Fengzhen
Published: December 2021

Crystalline silicon/compounds heterojunction (SCH) solar cells using oxides or fluorides as the electron or hole transport layers present great low-cost potential. In this paper, c-Si/SnO2 SCH solar cells are based on p-type c-Si substrates and use SnO2, prepared by atomic layer deposition, as the electron transport layers are investigated. By optimizing the SnO2 thickness and the device annealing process, a Voc of 718 mV and an efficiency of 20.1% are achieved on a champion SCH solar cell with an optimized SnO2 thickness of 3 nm. By analyzing the dark J–V curves, transport mechanisms of the silicon/compound heterojunction are investigated. It is proved that a strong inversion layer is induced in the p-type Si substrate, and a high hole barrier exists in the heterojunction region, which makes it a minority-carrier device. The induced inversion layer at the Si surface and the carrier selective transport effect of the SnO2 layer together enable the devices to achieve a high Voc.
Long-range model of vibrational autoionization in core-nonpenetrating Rydberg states of NO
Authors: Barnum Timothy J. , Clausen Gloria , Jiang Jun , Coy Stephen L. , Field Robert W.
Published: December 2021

In high orbital angular momentum (ℓ ≥ 3) Rydberg states, the centrifugal barrier hinders the close approach of the Rydberg electron to the ion-core. As a result, these core-nonpenetrating Rydberg states can be well described by a simplified model in which the Rydberg electron is only weakly perturbed by the long-range electric properties (i.e., multipole moments and polarizabilities) of the ion-core. We have used a long-range model to describe the vibrational autoionization dynamics of high-ℓ Rydberg states of nitric oxide (NO). In particular, our model explains the extensive angular momentum exchange between the ion-core and the Rydberg electron that had been previously observed in vibrational autoionization of f (ℓ = 3) Rydberg states. These results shed light on a long-standing mechanistic question around these previous observations and support a direct, vibrational mechanism of autoionization over an indirect, predissociation-mediated mechanism. In addition, our model correctly predicts newly measured total decay rates of g (ℓ = 4) Rydberg states because for ℓ ≥ 4, the non-radiative decay is dominated by autoionization rather than predissociation. We examine the predicted NO+ ion rotational state distributions generated by vibrational autoionization of g states and discuss applications of our model to achieve quantum state selection in the production of molecular ions.
Over 1.8 GW/cm2 beveled-mesa NiO/β-Ga2O3 heterojunction diode with 800 V/10 A nanosecond switching capability
Authors: Zhou F. , Gong H. H. , Wang Z. P. , Xu W. Z. , Yu X. X. , Yang Y. , Ren F.-F. , Gu S. L. , Zhang R. , Zheng Y. D. , Lu H. , Ye J. D.
Published: December 2021

In this Letter, we demonstrate a large-area (1-mm2) beveled-mesa p-NiO/β-Ga2O3 bipolar heterojunction diode (HJD) with a high Baliga's figure of merit of 1.84 (2.87) GW/cm2 from DC (pulsed) measurements. Benefiting from the suppression of electric field crowing at the designed mesa edge and bipolar current conductivity modulation, the resultant device exhibits advantageous characteristics, including a low subthreshold slope of 65 mV/decade, a low DC (pulsed) differential specific on-resistance of 2.26 (1.45) mΩ cm2, a high current density of 2 kA/cm2, and a high breakdown voltage of 2.04 kV. In particular, the Ga2O3 HJD exhibits an 800 V/10 A extreme switching capability with 16.4-ns reverse recovery characteristics, as well as high operation stability at a high temperature of 200 °C. This work, thus, makes a significant step toward reaching the promise of a high figure-of-merit in β-Ga2O3 power devices.
Fine structure in electronic transitions attributed to nitrogen donor in silicon carbide
Authors: Assmann N. , Persson C. , Kuznetsov A. Yu. , Monakhov E. V.
Published: December 2021

Nitrogen in group-IV semiconductors has become a well-established element of qubits capable of room-temperature operation. In silicon carbide, nitrogen can occupy different nonequivalent lattice sites, giving rise to different shallow donor states. We report a triplet fine structure in electronic transitions of nitrogen donors on the quasi-cubic carbon site in 4H silicon carbide with activation enthalpies of around 100 meV. The intensities of triplet components have a prominent dependence on the voltage bias. The activation enthalpies of the transitions exhibit the Poole–Frenkel effect, while no bias dependence is observed for the magnitude of splitting. A tentative explanation of the fine structure involves local symmetry changes due to stacking faults.
Extraction of intrinsic contact resistance in organic thin-film transistors with single channel length and high capacitance density
Authors: Kim Gunhee , Fuentes-Hernandez Canek , Choi Sangmoo , Jia Xiaojia , Kippelen Bernard
Published: December 2021

Accurate characterization of the intrinsic contact resistance is important for the optimization of organic thin-film transistors (OTFTs), especially in devices with high gate capacitance density. This study reports on a method for the extraction of the intrinsic, or gate-voltage independent, contact resistance from OTFTs. In contrast to the transfer length method (TLM), this method can be applied to devices with single geometry. The method is an extension of the previously reported Y-function method and combines the model proposed by Luan and Neudeck to analyze the effect of the gate voltage on the contact resistance. This method is first applied to OTFTs with a bottom-gate top-contact geometry having varying gate capacitance density values. The intrinsic contact resistance is found to decrease with increased gate capacitance density with values ranging between 4 kΩ cm and under 1 kΩ cm when the gate capacitance is changed from 36.6 to 231.7 nF/cm2, respectively. These values are in good agreement with those obtained using TLM experiments. This method is also shown to be applicable to OTFTs with top-gate bottom-contact geometry.
Modeling of small tungsten dust grains in EAST tokamak with NDS-BOUT++
Authors: Liu Zhuang , Ding Rui , Xu Xueqiao , Li Nami , Deng Guozhong , Sun Jizhong , Wang Dezhen , Feng Yan
Published: December 2021

To investigate the transport of small dusts as well as their evolution property along their trajectories, the NDS module is developed under the BOUT++ framework, a highly desirable C++ code package to perform parallel plasma fluid simulations with an arbitrary number of equations in three-dimensional curvilinear coordinates. Due to the severe dust ablation in fusion plasmas, the dust size would decrease from micrometer to nanometer, resulting in impurities. Small dusts in the simulations here are specified as tungsten spheres with the radii on or below the order of submicrometer. The Rayleigh limit is included in the charging process when the dust is ablated to the droplet phase. The simulation results from the NDS module show that a 200 nm radius spherical tungsten dust originated from upper divertor region of EAST Tokamak is ablated completely due to the intense heating from the incoming plasma inside the core region, well consistent with the CCD footage of EAST shot # 81459. It is also found that the magnetic field dominates the dust transport when the dust radius is below 100 nm during the ablation along the trajectory. Our simulations predict that a 10 nm radius spherical tungsten dust injected from the inner midplane is well constrained by the magnetic field, and it reaches the inner divertor target with a velocity on the order of km/s.
Rhombohedral and turbostratic boron nitride: X-ray diffraction and photoluminescence signatures
Authors: Moret Matthieu , Rousseau Adrien , Valvin Pierre , Sharma Sachin , Souqui Laurent , Pedersen Henrik , Högberg Hans , Cassabois Guillaume , Li Jianhan , Edgar J. H. , Gil Bernard
Published: December 2021

Boron nitride (BN) layers with sp2 bonding have been grown by metal organic chemical vapor deposition on AlN underlayers, which are deposited on c-plane sapphire substrates. Two different boron precursors were employed—trimethylboron and triethylboron—while ammonia was used as the nitrogen precursor. The BN obtained epitaxial BN films contain ordered rhombohedral (rBN) and partially ordered turbostratic (tBN) stackings as evidenced by x-ray diffraction analysis. We discriminatively identify the PL signatures of the rBN and tBN from those typical of the hexagonal (hBN) and Bernal stackings (bBN). The optical signature of tBN appears at 5.45 eV, and it intercalates between the two recombination bands typical of rBN at 5.35 eV (strong intensity) and 5.55 eV(weaker intensity). The analogs of the high intensity band at 5.35 eV in rBN sit at 5.47 eV for hBN and at 5.54 eV for bBN.
Measurement matrix uncertainty model-based microwave induced thermoacoustic sparse reconstruction in acoustically heterogeneous media
Authors: Liu Shuangli , Lu Yanxi , Zhu Xiaozhang , Jin Haoran
Published: December 2021

Microwave induced thermoacoustic has attracted broad attention in recent years because of its potential for clinical noninvasive detection. The model matrix in the model-based reconstruction method is often constructed by simulation, assuming that the media is acoustically homogeneous. However, the thermoacoustic signal waves propagate through acoustically heterogeneous media in real imaging scenes and are recorded by sparse sensor array. Thus, there is a perturbation between the actual and pre-designed measurement matrix, called measurement matrix uncertainty. In this Letter, an improved model is proposed to reconstruct the sound pressure distribution from sparse signals with phase distortion caused by variations in the speed of sound between tissues. The measured thermoacoustic signals are employed to construct a series of complex signals, which contain amplitude and phase information. The signal model's sparse constraint of the estimated sound pressure map is combined with the nonzero constraint of the random measurements' phases with respect to the amplitude-only measures. Our simulation and experiment results indicate that the proposed model helps to improve the image quality reconstructed by sparse sampling in acoustically heterogeneous media.
Artificial synapses based on electric stress induced conductance variation in vertical MoReS3 nanosheets
Authors: Xu Jiaqing , Leng Kangmin , Huang Xiaoxiao , Ye Yunyang , Gong Junfeng
Published: December 2021

As promising nonvolatile memory devices, memristors based on transition metal dichalcogenides, such as MoS2 and MoTe2, have received much attention for their polymorphism and distinct electronic characteristics. However, state-of-the-art memristors with horizontal placement of sandwiching 2D material layers suffer from poor performance in switching variability and endurance for the preparation and transfer process. Herein, we report a memristor based on vertical MoReS3 nanosheets spread on the surface of carbon fiber cloth. The atomic-scale thickness, combined with the structural transition from the T′ phase to the T″ phase in Janus MoReS3 nanostructures, lowers the spatial (device-to-device) and temporal (cycle-to-cycle) variation and prolongs the lifespan of the device during resistive switching processes. Furthermore, our memristor achieves a high device yield and accurate analogue programming and, thus, exhibits the synapse-like learning behavior such as short-term memory and long-term memory. These results demonstrate the potential of direct modulation of 2D materials with electric stress and motivate further research in implementation of artificial synapses.
Surface charge mediated polar response in ferroelectric nanoparticles
Authors: Co Kevin , Pamir Alpay S. , Nakhmanson Serge , Mangeri John
Published: December 2021

Interfacial phenomena in dielectric-ferroelectric composites have significant potential for promoting novel properties. Here, we utilize a dynamic Landau–Ginzburg–Devonshire methodology to elucidate the influence of an electrostatic self-interaction on the polarization behavior of spherical ferroelectric nanoparticles embedded in a dielectric matrix. By varying the particle volume and the dielectric permittivity of the surrounding medium, phase boundaries between states with polarization patterns exhibiting monodomains, structural, and electrical polydomains, and vortex-like topologies are observed in isolated particles. Under an applied bias, incomplete screening of surface charges leads to a size-dependent, monodomain-to-vortex topological phase transition that suppresses macroscopic polarization. The vortex topology observed in the polarization-suppressed region of the hysteresis originates from the minimization of surface charges at the particle-matrix interface, resulting in linear behavior and double hysteresis loops.
Adsorption, and controlled release of doxorubicin from cellulose acetate/polyurethane/multi-walled carbon nanotubes composite nanofibers
Authors: Alisani Reza , Rakhshani Navid , Abolhallaj Maryam , Motevalli Foojan , Abadi Parvaneh Ghaderi-shekhi , Akrami Mohammad , Shahrousvand Mohsen , Jazi Fariborz Sharifian , Irani Mohammad
Published: December 2021

The cellulose acetate (CA)/poly (ε-caprolactone diol)/poly (tetramethylene ether) glycol-polyurethane (PCL-Diol/PTMG-PU)/multi-walled carbon nanotubes (MWCNTs) composite nanofibers were prepared via two-nozzle electrospinning on both counter sides of the collector. The performance of synthesized composite nanofibers was investigated as an environmental application and anticancer delivery system for the adsorption/release of doxorubicin (DOX). The synergic effect of MWCNTs and DOX incorporated into the nanofibers was investigated against LNCaP prostate cancer cells. The status of MWCNTs and DOX in composite nanofibers was demonstrated by SEM, FTIR and UV–vis determinations. The adsorption tests using nanofibrous adsorbent toward DOX sorption was evaluated under various DOX initial concentrations (100–2000 mg l−1 ), adsorption times (5–120 min), and pH values (pH:2–9). Due to the fitting of isotherm and kinetic data with Redlich–Peterson and pseudo-second order models, both chemisorption and surface adsorption of DOX molecules mechanisms have been predicted. The drug release from both nanofibers and MWCNTs-loaded nanofibers was compared. The better drug sustained release profiles verified in the presence of composite nanofibers. LNCaP prostate cancer and L929 normal cells were treated to investigate the cytotoxicity and compatibility of synthesized composite nanofibers. The apoptosis/necrosis of hybrid nanofibers and MWCNTs loaded-nanofibers was investigated. The obtained results demonstrated the synergic effects of MWCNTs and DOX loaded-nanofibers on the LNCaP prostate cancer cells death.
Microemulsions and nanoemulsions modified with cationic surfactants for improving the solubility and therapeutic efficacy of loaded drug indomethacin
Authors: Mirgorodskaya Alla B , Koroleva Marina Yu , Kushnazarova Rushana A , Mishchenko Ekaterina V , Petrov Konstantin A , Lenina Oxana A , Vyshtakalyuk Alexandra B , Voloshina Alexandra D , Zakharova Lucia Ya
Published: December 2021

In this work, a noncovalent strategy was successfully used to modify colloidal stability and in vitro and in vivo efficacy of two amphiphilic formulations of the anti-inflammatory drug indomethacin. Namely, nanoemulsions and microemulsions based on oleic acid and nonionic surfactants have been produced and compared. The influence of cationic surfactants cetyltrimethylammonium bromide and its carbamate bearing analogue on the size characteristics, stability and ability to provide prolonged action of loaded drug indomethacin has been evaluated. Adding the positively charged molecules in the surface layer of nanoemulsions and microemulsions has shown the stability increase along with maintaining the size characteristics and homogeneity in time. Moreover, the carbamate modified analogue demonstrated beneficial behavior. Indomethacin loaded in microemulsions and nanoemulsions showed prolonged-release (10%–15% release for 5 h) compared to a free drug (complete release for 5 h). The rate of release of indomethacin from nanoemulsions was slightly higher than from microemulsions and insignificantly decreased with an increase in the concentration of the cationic surfactant. For carbamate surfactant nanocarrier loaded with fluorescence probe Nile Red, the ability to penetrate into the cell was supported by flow cytometry study and visualized by fluorescence microscopy. In vitro tests on anti-inflammatory activity of the systems demonstrated that the blood cell membrane stabilization increased in the case of modified microemulsion. The anti-inflammatory activity of the encapsulated drug was tested in rats using a carrageenan-induced edema model. Nanoemulsions without cationic surfactants appeared more efficient compared to microemulsions. Indomethacin emulsion formulations with carbamate surfactant added showed slower carrageenan-induced edema progression compared to unmodified compositions. Meanwhile, the edema completely disappeared upon treatment with emulsion loaded indomethacin after 4 h in the case of microemulsions versus 5 h in the case of nanoemulsions.
Design, manufacturing, and performance evaluation of a novel smart roller bearing equipped with shape memory alloy wires
Authors: Li Shuai , Hedayati Dezfuli Farshad , Alam M Shahria , Wang Jing-quan
Published: December 2021

In this study, a new type of seismic isolation device, called shape memory alloy (SMA) wire-based roller bearing (SMA-RB) is developed and introduced. The SMA-RB has been designed, manufactured, and experimentally tested. This bearing consists of cylindrical roller bearings and SMA wires with straight or cross configurations, as supplementary damping elements. In such a smart bearing, the superelastic (SE) SMA wires are passed through the hooks/pulleys attached to the supporting plates of the bearings in different configurations. The rollers provide lateral flexibility, and SMA wires supply energy dissipation and self-centering (SC) properties. In the manufacturing stage, a new mechanism for coupling wires (i.e. SMA wire joiner/coupler) is proposed. The results show that SMA wires, made of nickle titanium (NiTi), provide a SC damping mechanism with almost zero residual deformation which can effectively control the device from over-displacement. While using pulleys and newly designed wire joiners in the SMA-RB, the bearing can experience a stable cyclic behavior. Since the rollers generate a negligible amount of frictional force, the SE NiTi wires with a flag-shaped hysteresis mainly contribute to the overall shear hysteretic response of the SMA-RB. A triangular-shaped constitutive model can be used to accurately describe the hysteretic behavior of SMA-RB with different wire configurations.
Building energy simulations for different building types equipped with a high performance thermochromic smart window
Authors: Mann D , Yeung C , Habets R , Vroon Z , Buskens P
Published: December 2021

With constantly progressing climate change and global warming, we face the challenge to reduce our energy consumption and CO2 emission. To increase the energy-efficiency in buildings, we developed a thermochromic coating for smart windows which is optimized for intermediate climates. Here we present a building energy simulation study for the use of our smart window in the four main residential building types in the Netherlands. In the study we show that for all building types energy savings between 15-30% can be achieved. Hereby the impact of the windows on energy consumption is dependent on the window surface area as well as the total floor space. Furthermore we show that by the use of our new smart window, where the thermochromic coating is combined with a standard low-e coating, annual cost savings for energy between 220-445 € for a single household can be achieved. The thermochromic coating usually accounts for half of these cost savings, that is an addition in cost savings between 6-7.5 €/m2 glass. Due to the low material and processing costs for the thermochromic coating, a return on invest within 7 years should be feasible with these annual cost savings.
Developments to come to a circular construction economy; experiences in facilitating a local soil and sand depot
Authors: Entrop A G
Published: December 2021

In the construction industry the ambition to come to a circular economy will, with its vast material usage, be a hard nut to crack. This paper describes a research project part of the H2020 Cityloops project, in which it was expected that soil and sand depots could be an interesting subject to study. Already for many years and in multiple municipalities, these depots help to overcome mismatches regarding quality and quantity in demand and request of soil and sand. With the ambition to close material loops the construction industry might experience these kinds of mismatches also for an increasing number of other resources in the nearby future. Having positive experiences with her soil and sand depot, the municipality of Apeldoorn was open to give insights in the flows at her open-air soil and sand depot. The conducted research helped making processes transparent and valuable insights were gained. However, considering the great variety in building materials, products and components, it currently seems possible to handle only a small number of other material flows in the same way soil and sand are being handled and stored at a depot.
Development of a circularity assessment method for facade systems
Authors: Gulck Lisa Van , Leenknecht Eline , Debusseré Emiel , Steenkiste Jona Van , Steeman Marijke , Bossche Nathan Van Den
Published: December 2021

Various authorities identify the circular building strategy as the best way to reduce the environmental impact of the building sector. The EURECA project aims to develop a circular facade system for the renovation of high-rise buildings. The circularity of the facade systems proposed within the project should be evaluated in an objective manner. Current circularity assessment methods exist, however, they appear unfit to evaluate facade systems at an early design stage. Based on the analysis of existing assessment methods a new circularity assessment method is developed. The developed method allows to measure the circularity on element level with a limited amount of required information, allowing early stage decision-making. The method considers the parameters recycling, environmental cost, expected service life, component dependency, layer dependency and flexibility for reuse. The method is tested on four facade renovation systems: standard ETICS, circular ETICS, ventilated facade with rigid insulation and ventilated facade with flexible insulation. The circularity of each system can be represented by a radar chart, giving the score per parameter, or by a single score. In addition to the circular aspect, the financial aspect is added in the evaluation of the facade systems by using the Pareto front method.
The Circular Retrofit Lab: a multi-disciplinary development of a building envelope according to circular design qualities
Authors: Cambier Charlotte , Poppe Jeroen , Galle Waldo , Elsen Stijn , Temmerman Niels De
Published: December 2021

From 2016 until 2019, the Circular Retrofit Lab (CRL) was realised within the H2020-funded project Building As Material Banks (BAMB). The CRL was an experimental pilot project concerning the refurbishment of eight student housing modules in Brussels, Belgium. The lab aims to demonstrate how to implement circular building design in a retrofitting project. This paper discusses the design choices and the outcome of the CRL’s building envelope. That envelope consists of a modular façade system of prefabricated panels. The innovative, adaptable and reusable building solutions applied in the CRL have been developed in collaboration with various construction stakeholders and included, exceptionally in the design and construction process, also industrial partners. In this study, we go deeper into the impact of the multi-disciplinary approach on the resulting implementation of a circular building envelope. Through a reflexive learning-history workshop, we can show how the involvement of various actors and unconventional circularity requirements increase the complexity of the project, but also how they positively impact the reactivation of existing buildings and proved to be a lasting learning opportunity to all partners involved.
Legal instruments for the design of sustainable buildings
Authors: Kretschmer A , Zabek M , Tran K , Hildebrand L
Published: December 2021

Currently the building sector is under high pressure: the lack of affordable housing in conurbations and the need to implement environmental performance strategies require concepts that incorporate user needs with planetary boundaries. Against the background of global population growth and a rising demand for resources, urban densification is regarded as a major global trend. The pressure on cities is already recognizable today and studies predict a growing tendency for the next three decades. This is a sensitive situation which provides not only the chance but also the urgent necessity to implement strategies to reduce climate change effects. Regulations are necessary to guide this process in the building sector. Timber construction as well as reused and recycled material show potential to be part of the solution. Against this background, the research deals with the status-quo of current legal instruments to design and construct sustainable buildings. This article provides an overview of the legal instruments in relation to sustainable building processes in the German construction industry with a focus on timber buildings. The relevant standards and guidelines for sustainable building design are investigated by literature review. This includes German Model Building Code (MBO), parts of the DIN standards, the German Building Code (BauGB) and the Building Usage Ordinance (BauNVO) as well as the Model Timber Construction Directive (M-HFHHolzR). The regulations are applied on a multi-residential building in Cologne and discussed whether regulations are enabler or obstacle for this specific project. The results of the study show the urgent need for more flexibility within current inner-city projects to pursue an environmentally friendly design and construction.
Review of archetype development strategies for energy assessment at urban scale
Authors: Colleto G M , Gomes V
Published: December 2021

Understanding the built environment’s impacts is essential to support strategic planning and policy design for sustainable development now, and in the future. Modelling individual buildings and infrastructure at high level of detail is resource intensive. Thus, urban scale analyses demand simplifications that balance level of detail and scope broadness. For combining simplified modelling and extended scope, classification by archetypes emerge as a promising methodological approach to extend assessment scope beyond energy use simulation. Archetypes that include life cycle assessment (LCA) parameters can support circularity challenges diagnosis, mapping and predictions, strategies to close material and energy loops and their monitoring within urban built environments. We hypothesized that, upon limited complementation, operational and pre/post construction (embodied) datasets coupled with building grouping techniques satisfactorily represent the built stock to support cradle to grave LCA of built environments. Studies on the use of archetypes for this purpose are scarce, so this article reports findings of a Systematic Literature Review (SLR) on archetypes-based approaches for energy assessment that could inspire application in LCA studies at urban scale. The SLR highlighted a lack of methodological consensus, and that data availability seems to be the major limitation for archetype creation in most studies, which rarely present in-depth information on their development. The few investigations providing consistent methodological procedures actually detail the initial classification process. Transposing the archetype strategy from energy assessment to LCA at urban scale faces practical limitations. Several databases support operational energy studies, but the same does not apply to LCA. Urban building energy models typically overlook infrastructure. Also, statistical results depend directly on data input quality and data availability may compromise the quality of variable selection.
Bijlmermeer and Scampia: The potential of suburbs as centralities in sustainable and circular cities
Authors: Chiara Mazzarella P , Remoy Hilde
Published: December 2021

In the sustainable paradigm of the circular economy, waste is a resource to be valued. Similarly, in the circular city, fringe areas and urban wastescapes are places full of potential. This study consider two modern suburbs in Amsterdam and Naples. The two cases aims to compare the characteristics, potential and problems of the two districts and the ongoing actions for sustainable or circular urban regeneration. The objective is to identify the potential of these two European suburbs in the wider process of development of fair and circular cities. Therefore, this paper aims to answer to the following research question: Based on the two case studies Bijlmermeer and Scampia, what is the potential for circular and socially sustainable urban transformation of the 1960s suburbs? Analysing the main changes that have taken place over the last ten years in these complex areas, the main drivers are identified with the historical value of modern architecture landmarks, the opportunities offered by big green public spaces in dense urbanized areas, the presence of active place-based communities and their position in nodal points of the metropolitan areas.
SRDFM: Siamese Response Deep Factorization Machine to improve anti-cancer drug recommendation
Authors: Su Ran , Huang YiXuan , Zhang De-gan , Xiao Guobao , Wei Leyi
Published: December 2021

Predicting the response of cancer patients to a particular treatment is a major goal of modern oncology and an important step toward personalized treatment. In the practical clinics, the clinicians prefer to obtain the most-suited drugs for a particular patient instead of knowing the exact values of drug sensitivity. Instead of predicting the exact value of drug response, we proposed a deep learning-based method, named Siamese Response Deep Factorization Machines (SRDFM) Network, for personalized anti-cancer drug recommendation, which directly ranks the drugs and provides the most effective drugs. A Siamese network (SN), a type of deep learning network that is composed of identical subnetworks that share the same architecture, parameters and weights, was used to measure the relative position (RP) between drugs for each cell line. Through minimizing the difference between the real RP and the predicted RP, an optimal SN model was established to provide the rank for all the candidate drugs. Specifically, the subnetwork in each side of the SN consists of a feature generation level and a predictor construction level. On the feature generation level, both drug property and gene expression, were adopted to build a concatenated feature vector, which even enables the recommendation for newly designed drugs with only chemical property known. Particularly, we developed a response unit here to generate weighted genetic feature vector to simulate the biological interaction mechanism between a specific drug and the genes. For the predictor construction level, we built this level integrating a factorization machine (FM) component with a deep neural network component. The FM can well handle the discrete chemical information and both low-order and high-order feature interactions could be sufficiently learned. Impressively, the SRDFM works well on both single-drug recommendation and synergic drug combination. Experiment result on both single-drug and synergetic drug data sets have shown the efficiency of the SRDFM. The Python implementation for the proposed SRDFM is available at at https://github.com/RanSuLab/SRDFM Contact: ran.su@tju.edu.cn, gbx@mju.edu.cn and weileyi@sdu.edu.cn.
LipidOne: user-friendly lipidomic data analysis tool for a deeper interpretation in a systems biology scenario
Authors: Pellegrino Roberto Maria , Giulietti Matteo , Alabed Husam B R , Buratta Sandra , Urbanelli Lorena , Piva Francesco , Emiliani Carla
Published: December 2021

LC/MS-based analysis techniques combined with specialized lipid tool allow for the qualitative and quantitative determination of thousands of lipid molecules. Some recent bioinformatics tools have been developed to study changes in the lipid profile in case–control experiments and correlate these changes to different enzyme activity or gene expression. However, the existing tools have the limitation to treat only the assembled lipid molecules. In reality, each individual molecule can be considered as an assembly of smaller parts, often called building blocks. These are the result of a myriad of biochemical synthesis and transformation processes that, from a systems biology perspective, should not be ignored. Here, we present LipidOne, a new lipidomic tool which highlights all qualitative and quantitative changes in lipid building blocks both among all detected lipid classes and among experimental groups. Thanks to LipidOne, even differences in lipid building blocks can now be linked to the activity of specific classes of enzymes, transcripts and genes.

Availability and implementation

LipidOne software is freely available at www.dcbb.unipg.it/LipidOne and https://github.com/matteogiulietti/LipidOne.

Contact

roberto.pellegrino@unipg.it

Supplementary information

Supplementary data are available at Bioinformatics online.
Computed tomography assessment of saw-tooth cardiomyopathy: a case series
Authors: Berarducci Joaquin , Armenta-Moreno Javier Ivan , Espinola-Zavaleta Nilda , Cano-Zarate Roberto , Gutiérrez-Solana-Ossa Ana-Valentina , Keirns Candace
Published: December 2021

Background

Saw-tooth cardiomyopathy (STC) is an unusual type of left ventricular dysplasia. To our knowledge, six cases have been reported in the literature. Two new cases are presented with a review of all the case reports that have been published.

Case summary

Two patients with STC were examined. The first one was a 69-year-old woman with shortness of breath on mild exertion and chest pain, and the second was a 49-year-old man with a history of myocardial infarction who required stent implantation and is now asymptomatic. Both patients revealed findings of STC in the cardiac computed tomography (CT).

Discussion

When analysing the cases and comparing them to the ones reported in the literature; STC is a generally benign heart disease, although the clinical spectrum can range from asymptomatic to heart failure. Imaging studies such as cardiac magnetic resonance and cardiac CT are essential for the diagnosis.
Radiofrequency ablation to achieve durable pulmonary vein isolation
Authors: Mulder Mark J , Kemme Michiel J B , Allaart Cornelis P
Published: December 2021

Pulmonary vein isolation (PVI) by radiofrequency (RF) ablation is an important alternative to antiarrhythmic drugs in the treatment of symptomatic atrial fibrillation. However, the inability to consistently achieve durable isolation of the pulmonary veins hampers the long-term efficacy of PVI procedures. The large number of factors involved in RF lesion formation and the complex interplay of these factors complicate reliable creation of durable and transmural ablation lesions. Various surrogate markers of ablation lesion formation have been proposed that may provide information on RF lesion completeness. Real-time assessment of these surrogates may aid in the creation of transmural ablation lesions, and therefore, holds potential to decrease the risk of PV reconnection and consequent post-PVI arrhythmia recurrence. Moreover, titration of energy delivery until lesions is transmural may prevent unnecessary ablation and subsequent adverse events. Whereas several surrogate markers of ablation lesion formation have been described over the past decades, a ‘gold standard’ is currently lacking. This review provides a state-of-the-art overview of ablation strategies that aim to enhance durability of RF-PVI, with special focus on real-time available surrogates of RF lesion formation in light of the biophysical basis of RF ablation.
Patterns of Caregiving Among Older Adults With and Without Dementia: A Latent Class Analysis
Authors: Ali Talha , McAvay Gail J , Monin Joan K , Gill Thomas M
Published: December 2021

Objectives

We identify common patterns of caregiving or “care types” among older adults with and without dementia. Prior research has focused on primary caregivers and on the independent effects of individual caregiving attributes. We examine multiple caregivers of older adults, including the primary caregiver, and how multiple caregiving attributes co-occur to shape caregiving types.

Methods

We link 2015 care recipient (N = 1,423) and unpaid caregiver data (N = 2,146) from the National Health and Aging Trends Study and the National Study of Caregiving. Latent class analysis of caregiving attributes, representing care intensity and regularity, and various care activities, was used to construct care types. Multinomial logistic regression was used to examine if the recipients’ dementia status and caregivers’ background characteristics predicted membership in care types.

Results

Five distinguishable care types were identified. Caregivers who were female, adult children, or coresidents, those caring for persons with dementia, and those who had paid help had higher odds of being in the more demanding care types. Conversely, older, White caregivers and those with support for their caregiving activities were less likely to be in a demanding care type.

Discussion

Care types can help us understand sources of heterogeneity in caregiving and effectively target caregiver support services and interventions.
Considerations of sex and gender dimensions by research ethics committees: a scoping review
Authors: Saxena Abha , Lasher Emily , Somerville Claire , Heidari Shirin
Published: December 2021

Despite a growing consensus on the importance of integrating sex and gender in health research, research across disciplines continues to be conducted and reported without a gender focus. Research ethics committees (RECs) can play a particularly powerful role in identifying the gender gaps at an early stage of the development of research protocols. Their role is missing in the dialogue related to improving gender awareness and analysis in health research. A scoping review was conducted to examine the extent to which RECs discuss and consider the inclusion and analysis of sex and gender in health research and to examine the literature regarding the gender balance of RECs. The limited literature around gender and research ethics reveals the power and potential of RECs to ensure that gender dimensions are thoughtfully included in health research, and sheds light on the gaps that exist. These include an under-representation of women on RECs, a lack of awareness of the importance of gender-related aspects in health research and a paucity of gender-related training to RECs. Guidelines such as the Sex and Gender Equity in Research guidelines are required for RECs to strengthen the ways in which health research is gendered from conception of a research protocol to its publication.
High Rickettsial Diversity in Rodents and Their Ectoparasites From the Central Highlands of Madagascar
Authors: Rasoamalala Fanohinjanaharinirina , Parany Mamionah N J , Rahajandraibe Soloandry , Rakotomanga Malala N , Ramihangihajason Tojo , Soarimalala Voahangy , Boyer Sébastien , Rajerison Minoarisoa , Ramasindrazana Beza
Published: December 2021

Rickettsioses are among emerging infectious diseases around the world. In Madagascar, little information is available regarding Rickettsia (Rickettsiales: Rickettsiaceae) diversity and their potential impacts on public health. In fact, molecular screening of ectoparasites of mammals reported the presence of three species, Rickettsia africae, Rickettsia typhi, and Rickettsia felis. The present study aims to investigate the diversity of Rickettsia in small mammals and associated ectoparasites (fleas and ticks) using a molecular approach. In September and December 2016, fieldworks were undertaken in two districts of Madagascar to capture small mammals using standard traps (Tomahawk and Sherman traps) and collect associated ectoparasites. In total, 12 taxa of ectoparasites (5 flea and 7 tick species) were collected from 89 individuals of four species of terrestrial small mammals. Rickettsia spp. were molecularly identified in one specimen of Rattus rattus (Rodentia: Muridae), one specimen of Pulex irritans (Siphonaptera: Pulicidae) as well as four specimens of Ixodes cf. colasbelcouri (Ixodida: Ixodidae). This study showed the presence of three phylogenetically distinct taxa of Rickettsia in small mammals and their ectoparasites. The current study broadens our knowledge on the diversity of Rickettsia in the Central Highlands of Madagascar and highlights for the first time the presence of Ri. felis in R. rattus and in tick, I. cf. colasbelcouri in Madagascar. Additional studies are needed to have exhaustive information on Rickettsia in small mammals and their ectoparasites, to determine their pathogenicity as well as their potential effects on public health in order to update the national policy for the control of emerging infectious diseases in Madagascar.
Assessing Durability and Safety of Permethrin Impregnated Uniforms Used by Outdoor Workers to Prevent Tick Bites after One Year of Use
Authors: Richards Stephanie L , Driver Jeffrey , Dyer Megan C , Mather Thomas N , Funkhouser Sheana , Mitchell Cedar , Anne Balanay Jo , White Avian , Meshnick Steven
Published: December 2021

Long lasting permethrin-impregnated (LLPI) clothing can retain permethrin and repel ticks for up to three months and without exceeding EPA-approved safe levels; however, little is known about longer term effects of wearing LLPI clothing. Here, permethrin content was measured in new forester pants soon after initial impregnation (Insect Shield) and again one year later after being repeatedly worn by foresters in the field. Urine samples were collected from foresters for biomonitoring of permethrin metabolites at multiple time intervals (pre-use, one-month, three-to-four-months, and one-year post-use). Lethality against nymphal Ixodes scapularis Say was measured in clothing after one year of wear by foresters. Furthermore, to test potential variability in permethrin impregnation of different batches of clothing, separate sets of clothing were anonymously sent to Insect Shield for permethrin treatment over a period of three months and permethrin was quantified. Results demonstrated 33% of participants’ pants had no measurable permethrin after one year of wear and permethrin content and tick mortality varied significantly between clothing. Only two of the participants’ clothing resulted in ≥ 30% tick mortality after one year of wear. Significant differences were observed in 3-PBA and trans-DCCA, but not cis-DCCA metabolites in participants over the four measured time points and were higher than general United States population levels. This study provides practical information on the safety (measured by urinary metabolites) over time of LLPI clothing. It also provides snapshots (pre-washing and after one year of wear) of effectiveness of LLPI clothing as personal protective equipment against ticks for outdoor workers.