Low Density Research Articles

Experimental investigation of utilizing coconut shell ash and coconut shell granules as aggregates in coconut coir reinforced concrete

In the agricultural industry, coconut shells are one of the most generated wastes worldwide. In particular, studies in the Philippines show that the maximum capacity of the organic decomposition processes of agricultural products is exceeded due to the increasing agricultural activities. On the other hand, in the construction industry, cement production accounts for billions of tons of carbon dioxide emissions yearly. To address the said biowaste disposal problem, and environmental implications of the growing construction industry, this study evaluated the potential of utilizing coconut shell ash (CSA) and coconut shell granules (CSG) in concrete production as alternatives to cement and sand, being the conventional aggregates, respectively. Additionally, coconut coir (CC) was incorporated as fiber reinforcements in concrete. The experiment consisted of 15 mix designs using different proportions of CSA and CSG, ranging from 0% to 20%, and CC fiber reinforcements, ranging from 0% to 2%. The tests conducted on fresh concrete involved measuring its slump and unit weight, while the 28-day cured samples were tested for compressive and tensile strengths. Results showed that high concentrations of CSA, CSG and CC, when combined in the concrete mix, leads to poor workability; on the other hand, the modified mixes generally had lower unit weights than the conventional concrete. These are associated to the higher absorption rate, but lower density of the said agri-wastes than the conventional aggregates. In terms of the compressive and tensile strengths, all modified mixes produced lower strengths than the conventional concrete. Nonetheless, Response Surface Methodology (RSM) was utilised to model the relationship between the different independent variables considered in the study, namely CSA, CSG and CC contents, and their corresponding response to the compressive and tensile strengths. Based on the generated RSM Model, the optimum combination for obtaining the maximum strength consisted of 2% CC, resulting in a compressive and tensile strength of 23.046 MPa and 3.315 MPa, respectively. Overall, CSG-CSA coconut coir reinforced concrete is found to be a viable sustainable alternative for structures requiring low-strength, non-structural concrete, such as concrete slab patios and pathways.

The Simplified Approach to the Bose Gas Without Translation Invariance

The simplified approach to the Bose gas was introduced by Lieb in 1963 to study the ground state of systems of interacting Bosons. In a series of recent papers, it has been shown that the simplified approach exceeds earlier expectations, and gives asymptotically accurate predictions at both low and high density. In the intermediate density regime, the qualitative predictions of the simplified approach have also been found to agree very well with quantum Monte Carlo computations. Until now, the simplified approach had only been formulated for translation invariant systems, thus excluding external potentials, and non-periodic boundary conditions. In this paper, we extend the formulation of the simplified approach to a wide class of systems without translation invariance. This also allows us to study observables in translation invariant systems whose computation requires the symmetry to be broken. Such an observable is the momentum distribution, which counts the number of particles in excited states of the Laplacian. In this paper, we show how to compute the momentum distribution in the simplified approach, and show that, for the simple equation, our prediction matches up with Bogolyubov’s prediction at low densities, for momenta extending up to the inverse healing length.

Cyclic testing of standalone ALIF versus TLIF in lumbosacral spines of low bone mineral density: an ex vivo biomechanical study.

Screwed anterior lumbar interbody fusion (SALIF) alleviates the need for supplemental posterior fixation leading to reduction of perioperative morbidity. Specifically, elderly and multimorbid patients would benefit from shorter operative time and faster recovery but tend to have low bone mineral density (BMD). The current study aimed to compare loosening, defined as increase of ROM and NZ, of SALIF versus transforaminal lumbar interbody fusion (TLIF) under cyclic loading in cadaveric spines with reduced BMD. Twelve human spines (L4-S2; 6 male 6 female donors; age 70.6 ± 19.6; trabecular BMD of L5 84.2 ± 24.4mgHA/cm3, range 51-119mgHA/cm3) were assigned to two groups. SALIF or TLIF were instrumented at L5/S1. Range of motion (ROM) and neutral zone (NZ) were assessed before and after axial cyclic loading (0-1150N, 2000 cycles, 0.5Hz) in flexion-extension (Flex-Ext), lateral bending, (LB), axial rotation (AR). ROM of the SALIF specimens increased significantly in all loading directions (p ≤ 0.041), except for left AR (p = 0.053), whereas for TLIF it increased significantly in left LB (p = 0.033) and Flex (p = 0.015). NZ of SALIF showed increase in Flex-Ext and LB, whereas NZ of TLIF did not increase significantly in any motion direction. Axial compression loading caused loosening of SALIF in Flex-Ext and LB, but not TLIF at L5/S1 in low BMD specimens. Nevertheless, Post-cyclic ROM and NZ of SALIF is comparable to TLIF. This suggests that, neither construct is optimal for the use in patients with reduced BMD.

Dibutyl phthalate released by solitary female locusts mediates sexual communication at low density

Sex pheromones play a crucial role in mate location and reproductive success. Insects face challenges in finding mates in low-density environments. The population dynamics of locusts vary greatly, ranging from solitary individuals to high-density swarms, leading to multiple-trait divergence between solitary and gregarious phases. However, differences in sexual communication between solitary and gregarious locusts have not been sufficiently explored. Herein, we found that solitary locusts but not gregarious ones heavily rely on a single compound, dibutyl phthalate (DBP), for sexual communication. DBP is abundantly released by solitary female locusts and elicits strong attraction of male solitary and gregarious locusts. Solitary adult males display much higher electrophysiological responses to DBP than adult females. Additionally, LmigOr13 was identified as the DBP-specific odorant receptor expressed in neurons housed in basiconic sensilla. Male LmigOr13-/- mutants generated by CRISPR/Cas9 have low electrophysiological responses and behavioral attraction to DBP in both laboratory and field cage experiments. Notably, the attractiveness of DBP to male locusts becomes more evident at lower population densities imposed by controlling the cage size. This finding sheds light on the utilization of a sex pheromone to promote reproductive success in extremely low-density conditions and provides important insights into alternative approaches for population monitoring of locusts.

Non-monotonic relations of galaxy star formation, radius, and structure at fixed stellar mass

Abstract We investigate the relation between galaxy structure and star formation rate (SFR) in a sample of ∼2.9 × 104 central galaxies with z < 0.0674 and axial ratios b/a > 0.5. The star-forming main sequence (SFMS) shows a bend around the stellar mass of M* ≤ Mc = 2 × 1010M⊙. At M* ≤ Mc the SFMS follows a power-law $\text{SFR}\propto {}M_\ast ^{0.85}$, while at higher masses it flattens. Mc corresponds to a dark matter halo mass of Mvir ∼ 1011.8M⊙ where virial shocks occurs. Some galaxy structure (e.g., half-light radius, Re) exhibits a non-monotonic dependence across the SFMS at a fixed M*. We find $\text{SFR}\propto {R_e^{-0.28}}$ at fixed M*, consistent with the global Kennicutt-Schmidt (KS) law. This finding suggests that galaxy sizes contribute to the scatter of the SFMS. However, at M* > Mc the relationship between SFR and Re diminishes. Low-mass galaxies above the mean of the SFMS have smaller radii, exhibit compact and centrally concentrated profiles resembling green valley (GV) and quiescent galaxies at the same mass, and have higher $M_{\text{H}_2}/M_\rm{HI}$. Conversely, those below the SFMS exhibit larger radii, lower densities, have no GV or quiescent counterparts at their mass and have lower $M_{\rm{H}_2}/M_\rm{HI}$. The above data suggest two pathways for quenching low-mass galaxies, M* ≤ Mc: a fast one that changes the morphology on the SFMS and a slow one that does not. Above Mc, galaxies below the SFMS resemble GV and quiescent galaxies structurally, implying that they undergo a structural transformation already within the SFMS. For these massive galaxies, CG are strongly bimodal, with SFMS galaxies exhibiting negative color gradients, suggesting most star formation occurs in their outskirts, maintaining them within the SFMS.

Optimizing Masonry Mortar: Experimental Insights into Physico-Mechanical Properties Using Recycled Aggregates and Natural Fibers

The European Green Deal establishes the efficient management of construction resources as one of its main lines of action. In this sense, the recovery of construction and demolition waste for its reincorporation into the manufacturing process of new sustainable materials has become necessary for the industry. This work deals with the physical and mechanical characterization of cement mortars made with recycled concrete aggregates and reinforced with natural fibers. The reinforcement fibers used (abaca, coconut, and toquilla) are more environmentally friendly compared to traditional synthetic reinforcements. The aim of this research is to analyze the main physico-mechanical properties of these sustainable cement mortars. The results show that mortars made with recycled sand have a lower density and better thermal performance than traditional mortars. In addition, with the incorporation of these natural fibers, the flexural strength of the mortars with recycled aggregate increased by up to 37.6%. Another advantage obtained from the incorporation of these natural fibers is the reduction in shrinkage in the masonry mortars during the drying process, giving them greater dimensional stability and making their behavior similar to that of traditional mortars. Thus, this work shows the potential application of masonry mortars produced under circular economy criteria and their application in the building sector.

Boric acid toxic sugar bait suppresses male Aedes aegypti (Diptera: Culicidae): wing beat frequency and amplitude, flight activity, fecundity, insemination, and mate-finding Allee effect.

Controlling the spread of arboviral diseases remains a considerable challenge due to the rapid development of insecticide resistance in Aedes mosquitoes. This study evaluated the effects of boric acid-containing toxic sugar bait (TSB) on field populations of resistant Aedes aegypti mosquitoes. In addition, this study examined the flight activity and wing beat frequency and amplitude of males and the flight activity, fecundity, and insemination of females after pairing with males exposed to TSB. The population dynamics of Aedes mosquitoes under imbalanced sex ratios were examined to simulate realistic field conditions for male suppression under the effect of TSB. The mortality of male mosquitoes was consistently high within 24 h after exposure. By contrast, the mortality of female mosquitoes was inconsistent, with over 70% mortality observed at 168 h. The flight activity and wing beat amplitude of treated males were significantly lower than those of controls, but no significant difference in wing beat frequency was detected. The fecundity and insemination of treated female mosquitoes were lower than those of controls. A simulation study indicated that considerably low male population densities led to mating failures, triggering a mate-finding Allee effect and resulting in persistently low population levels. Boric acid-containing TSB could effectively complement current chemical intervention approaches to control resistant mosquito populations. TSB is effective in reducing field male populations and impairing male flight activity and female-seeking behavior, resulting in decreased fecundity and insemination. Male suppression due to TSB potentially results in a small mosquito population. © 2024 Society of Chemical Industry.

Fabrication of Fully Positively Charged Layer-by-Layer Polyelectrolyte Nanofilms with pH-Dependent Swelling Properties.

Nanofilms fabricated by layer-by-layer (LbL) assembly from polyelectrolytes (PEs) are important materials for various applications. However, PE films cannot retain the charges along the polymer chains during fabrication, resulting in a low charge density. In this study, the preparation of LbL nanofilms with preserved positive charges via a controllable and efficient approach was achieved. To fabricate fully positively charged (FPC) LbL nanofilms, a polycation, poly-l-lysine, was partially grafted with azide and alkyne groups. Through copper-catalyzed azide-alkyne cycloaddition and the LbL procedure, nanofilms were fabricated with all of the individual layers covalently bonded, improving the pH stability of the nanofilms. Because the resulting nanofilms had a high charge density with positive charges both inside and on the surface, they showed unique pH-dependent swelling properties and adsorption of negatively charged molecules compared with those of traditional polyelectrolyte LbL nanofilms. This kind of FPC nanofilm has great potential for use in sensors, diagnostics, and filter nanomaterials in the biomedical and environmental fields.

Estimates of late Early Cretaceous atmospheric CO2 from Mongolia based on stomatal and isotopic analysis of Pseudotorellia.

The Aptian-Albian (121.4-100.5 Ma) was a greenhouse period with global temperatures estimated as 10-15°C warmer than pre-industrial conditions, so it is surprising that the most reliable CO2 estimates from this time are <1400 ppm. This low CO2 during a warm period implies a very high Earth-system sensitivity in the range of 6 to 9°C per CO2 doubling between the Aptian-Albian and today. We applied a well-vetted paleo-CO2 proxy based on leaf gas-exchange principles (Franks model) to two Pseudotorellia species from three stratigraphically similar samples at the Tevshiin Govi lignite mine in central Mongolia (~119.7-100.5 Ma). Our median estimated CO2 concentration from the three respective samples was 2132, 2405, and 2770 ppm. The primary reason for the high estimated CO2 but with relatively large uncertainties is the very low stomatal density in both species, where small variations propagate to large changes in estimated CO2. Indeed, we found that at least 15 leaves are required before the aggregate estimated CO2 approaches that of the full data set. Our three CO2 estimates all exceeded 2000 ppm, translating to an Earth-system sensitivity (~3-5°C/CO2 doubling) that is more in keeping with the current understanding of the long-term climate system. Because of our large sample size, the directly measured inputs did not contribute much to the overall uncertainty in estimated CO2; instead, the inferred inputs were responsible for most of the overall uncertainty and thus should be scrutinized for their value choices.

Role of dislocations on martensitic transformation temperatures and microstructure: A molecular dynamics study

Microstructure and defects strongly affect martensitic transformations in metallic alloys. Significant progress has been made in understanding the atomic-level processes that control the role of grain boundaries and precipitates in these solid-to-solid phase transformations. Yet, the role of dislocations and their structures on martensitic transformation temperature and the resulting microstructure remains unclear. Therefore, we used large-scale molecular dynamics simulations to study the forward and reverse transformation of a martensitic material modeled after Ni63Al37 under cyclic thermal loading. The simulations reveal that dislocations in the austenite phase act as one-dimensional seeds for the martensite phase, which is present at temperatures significantly above the martensite start value. We find a reduction in the dislocation density during cyclic thermal loading, which results in the increase in martensite and austenite transition temperatures, in agreement with experiments. Importantly, we extracted a critical martensitic nuclei size for developing stable domains and found that relatively low dislocation densities are needed to grow independent martensitic variants resulting in a multi-domain structure.

Laser driven wake wave in pair-ion electron plasma with inclusion of ion dynamics

The generation of laser driven plasma wake wave has been investigated in hydrogen pair-ion electron plasma. The consideration of dynamics of the positive and negative ion pair have been adopted. Inclusion of the ion motion has the effect of modifying the electric field and density profiles of the wake wave. This has been demonstrated by observing the variation of the electron density and electric field profiles with the change in positive ion/negative ion concentration. High density spikes and sawtooth like electric field profiles (indication of wave breaking) are observed to transform into sinusoidal electric field profile and low amplitude density profile when the positive ion density in the plasma system is kept higher. Furthermore, we observe the variation of the electric field amplitude of the wake wave with the laser pulse width. This feature is the indication of the possibility of hybrid acceleration (Direct Laser Acceleration and wake field acceleration) of accelerated beam. The results are quite relevant in laser plasma interaction field in experimental physics and also in planetary environment.

Anethole Regulated Crystallization for High Efficiency Carbon‐Based Perovskite Solar Cells

AbstractTwo‐step sequential deposition is a widespread technique for the fabrication of perovskite films, renowned for its better control of the crystallization process. However, achieving a well‐controlled and complete reaction of PbI2 by organic ammonium salts remains a key challenge. Previous studies have predominantly focused on regulating the properties of the PbI2 layer while paying less attention to the high reactivity of organic ammonium salts. In this study, the natural molecule anethole is first explored to control perovskite crystallization during two‐step sequential deposition, focusing on the reactivity modulation of organic formamidine ion (FA+). It is demonstrated that FA+ exhibits strong hydrogen bond interactions with anethole, inhibiting the high reactivity of FA+ and effectively delaying the rapid reaction between FAI and PbI2. This decelerates the crystallization kinetics of perovskite films, facilitating the orderly and complete reaction of PbI2 by FAI while suppressing detrimental δ‐phase formation. Consequently, FA‐based perovskite films with high crystallinity, preferred orientation, and low defect state density are obtained. The fabricated planar hole transport layer‐free carbon electrode perovskite solar cells deliver an efficiency of 20.41% (certified efficiency of 20.0%), which is a new record for this kind of solar cell.

Prevalence of Osteoporosis and Sarcopenia in Middle-Aged Subjects with Low Back Pain

Abstract Objective The genesis of both osteoporosis and sarcopenia is multifactorial, complicated, and interrelated. The present study has been undertaken to analyze the prevalence of low bone mineral density (BMD) and the pattern of imaging markers of sarcopenia (paraspinal skeletal muscle area [SMA] and skeletal muscle index [SMI] with respect to clinicodemographic profile in middle-aged patients (30–45 years) undergoing evaluation for low back pain (LBP). Materials and Methods Magnetic resonance imaging (MRI) of the lumbosacral spine and/or sacroiliac joints was done on 3T MRI. BMD of the lumbar spine (L1 to L4) was assessed using a dual-energy X-ray absorptiometry scan. SMA was calculated by measuring the cross-sectional area of paraspinal muscles (bilateral psoas, erector spinae, and multifidus), and SMI was calculated by dividing SMA by height2. Results The prevalence of osteoporosis was 12.1% in patients of age 30 to 45 years presenting with LBP. Both osteoporosis and paraspinal muscle mass were statistically associated with the duration of symptoms (p-value &lt;0.05). No statistically significant difference was observed in different MRI findings, that is, normal, inflammatory, infective, and degenerative etiology. Conclusion Low BMD and loss of muscle mass in cases with LBP are more related to duration of disease rather than etiology or gender in middle-aged subjects. Early intervention to manage LBP may prevent progression to osteoporosis and sarcopenia in young adults.

Carbon Dioxide Oil Repulsion in the Sandstone Reservoirs of Lunnan Oilfield, Tarim Basin

The Lunnan oilfield, nestled within the Tarim Basin, represents a prototypical extra-low-permeability sandstone reservoir, distinguished by high-quality crude oil characterised by a low viscosity, density, and gel content. The effective exploitation of such reservoirs hinges on the implementation of carbon dioxide (CO2) flooding techniques. This study, focusing on the sandstone reservoirs of Lunnan, delves into the mechanisms of CO2-assisted oil displacement under diverse operational parameters: injection pressures, CO2 concentration levels, and variations in crude oil properties. It integrates analyses on the high-pressure, high-temperature behaviour of CO2, the dynamics of CO2 injection and expansion, prolonged core flood characteristics, and the governing principles of minimum miscible pressure transitions. The findings reveal a nuanced interplay between variables: CO2’s density and viscosity initially surge with escalating injection pressures before stabilising, whereas they experience a gradual decline with increasing temperature. Enhanced CO2 injection correlates with a heightened expansion coefficient, yet the density increment of degassed crude oil remains marginal. Notably, CO2 viscosity undergoes a substantial reduction under stratigraphic pressures. The sequential application of water alternating gas (WAG) followed by continuous CO2 flooding attains oil recovery efficiency surpassing 90%, emphasising the superiority of uninterrupted CO2 injection over processes lacking profiling. The presence of non-miscible hydrocarbon gases in segmented plug drives impedes the oil displacement efficiency, underscoring the importance of CO2 purity in the displacement medium. Furthermore, a marked trend emerges in crude oil recovery rates as the replacement pressure escalates, exhibiting an initial rapid enhancement succeeded by a gradual rise. Collectively, these insights offer a robust theoretical foundation endorsing the deployment of CO2 flooding strategies for enhancing oil recovery from sandstone reservoirs, thereby contributing valuable data to the advancement of enhanced oil recovery (EOR) technologies in challenging, low-permeability environments.

High performance power handling in the absence of an H-mode edge in negative triangularity DIII-D plasmas

Experiments performed during strongly-shaped high-power diverted negative triangularity (NT) experiments in DIII-D achieved detached divertor conditions and a transient-free edge, showcasing the potential for application of NT to a core-edge integrated reactor-like scenario and providing the first characterization of the parametric dependencies for detachment onset. Detached divertor conditions will be required in future devices to mitigate divertor heat fluxes. Access to dissipative divertor conditions was investigated via an increase in upstream density. Detachment onset at the outer strike point was achieved with H-mode level confinement H98−y2∼1 and reactor-relevant normalized pressures βN∼2 . Confinement degradation was observed with deeper detachment, associated with the loss of an electron temperature pedestal. Differences in geometry, radial transport, impact of cross field drifts are discussed to explain differences in access to detachment in NT discharges. Higher normalized densities, with respect to equivalent discharges in positive triangularity, were necessary to achieve detachment, partially explained by the shorter parallel connection length to the targets. The effect of cross-field particle drifts (E×B, B ×∇ B) on access to detachment was demonstrated by the lower upstream density needed to access detachment with ion B ×∇ B drift directed outside of the active divertor (Greenwald fraction fGw∼ 0.9–1.0 vs fGw∼ 1.3). The upstream density at detachment onset was observed to increase linearly with plasma current with ion B ×∇ B drift into the divertor, consistent with the observed narrowing of the scrape-off layer heat flux width λ q . Edge fluid simulations capture separatrix densities needed to achieve detachment in NT plasma and their dependence on drift direction. The ability to reproduce detachment dynamics in NT plasma increases the confidence in future design studies for NT divertors.

Effects of Ultrasound-Assisted Soy Lecithin Addition on Rehydration Behavior and Physical Properties of Egg White Protein Powder

This study investigated the effects of ultrasound-assisted soybean lecithin (SL) on the rehydration behavior and physical properties of egg white protein powder (EWPP) and its ability to enhance the efficacy of EWPP instant solubility. The results of rehydration, including wettability and dispersibility, indicated that ultrasound (200 W)-assisted SL (5 g/L) addition had the shortest wetting time and dispersion time, which were 307.14 ± 7.00 s and 20.95 ± 2.27 s, respectively. In terms of powder properties, the EWPP with added SL had lower lightness, moisture content and bulk density. In addition, the increase in average particle size, net negative charge, free sulfhydryl group content and surface hydrophobicity indicated that ultrasound treatment facilitated the protein structures unfolding and promoted the formation of SL-EWP complexes. Overall, our study provided a new perspective for the food industry regarding using ultrasound technology to produce instant EWPP with higher biological activity and more complete nutritional value.

Total nitrogen and phosphorus loads in surface runoff from urban land use (city of Lublin) under climate change.

An expansion of impervious surfaces in urban areas leads to increases of nutrient loads discharged with the surface runoff to receivers. A study of a different density of urban development impact on total nitrogen (TN) and phosphorus (TP) loads from the city of Lublin (eastern Poland) with the use of the SWAT (Soil & Water Assessment Tool) model was performed. To distinguish between areas with high and low density of urban development (UHD and ULD), a special analysis of hydrological parameters has been proposed. Moreover, to investigate the impact of climate change, four variant scenarios were taken into account, combining the RCP (representative concentration pathway) 4.5 and 8.5 forecasts and the adopted time horizons (2026-2035 and 2046-2055). The results showed a much higher share of TN and TP from UHD compared to ULD (86%-32 022kg/year and 89%-2574kg/year, respectively). In addition, the variant scenarios showed that the forecasted increase in precipitation and temperature will result in increased loads of nutrients from UHD and ULD up to 30%. Furthermore, the current increase of inhabitant number, due to the Ukrainian war migration and the common tendency to convert agricultural land to residential areas, could contribute to further expansion of UHD and ULD areas and an additional increase of nutrient loads.

Lift-connected surface codes

We use the recently introduced lifted product to construct a family of quantum low density parity check codes (QLDPC codes). The codes we obtain can be viewed as stacks of surface codes that are interconnected, leading to the name lift-connected surface (LCS) codes. LCS codes offer a wide range of parameters—a particularly striking feature is that they show interesting properties that are favorable compared to the standard surface code. For example, already at moderate numbers of physical qubits in the order of tens, LCS codes of equal size have lower logical error rate or similarly, require fewer qubits for a fixed target logical error rate. We present and analyze the construction and provide numerical simulation results for the logical error rate under code capacity and phenomenological noise. These results show that LCS codes attain thresholds that are comparable to corresponding (non-connected) copies of surface codes, while the logical error rate can be orders of magnitude lower, even for representatives with the same parameters. This provides a code family showing the potential of modern product constructions at already small qubit numbers. Their amenability to 3D-local connectivity renders them particularly relevant for near-term implementations.

The Prevalence and Histological Characteristics of the Double Capsule Phenomenon in Breast Augmentation With Implants.

Double capsule formation around breast implants is associated with implant rotation and seroma. However, the prevalence and histological characteristics remain unclear. To quantify the prevalence of double capsule formation between different implant surface textures and to explore the histological differences between the inner- and outer capsules from breast implant capsule biopsies. The study was performed on data from the Copenhagen Breast Implant (COBI) Biobank comparing the prevalence of double capsule formation around Allergan Biocell implants (Allergan, Dublin, Ireland), Eurosilicone Cristalline implants (GC Aesthetics, Dublin, Ireland), and Mentor Siltex implants (Mentor, Irvine, CA). The histological characteristics of the inner and outer capsules was analyzed using a validated assessment tool. The study included data from 588 patients and 1128 implants. Double capsule formation was found around 25 implants resulting in an overall prevalence of 2.5% for textured implants. Mentor implants with a Siltex surface had a double capsule prevalence of 0.72%, which was significantly lower than the prevalence for Allergan implants with a Biocell surface (7.8%), (P<.001), and Eurosilicone implants with a Cristalline surface (3.4%), (P=.03). Histological analysis showed that inner capsules had lower cellular density (P=.04) and were more calcified (P=.03) compared with outer capsules. The risk of double capsule formation was highly correlated with the roughness of the breast implant texture, with the risk of double capsule formation around Mentor Siltex implants being significantly lower than that of macrotextured implants. The histological analysis implies that loss of vascularization to the inner capsule results in a lower cellular density and more frequently calcification.

Controlled fabrication of flexible graphene aerogels via naturally dried and its photocatalysis-persulfate activation for ciprofloxacin degradation under sunlight

Materials for environmental purification should have not only the high purification efficiency, but also the character of mechanical strength, stabilized performance and no secondary pollution. Here, the flexible graphene aerogel (GA) was obtained via a controlled natural drying method combined with hydrothermal process. The effects of preparation conditions on GA, such as NH4•OH dose, H3BO3 dosage, ascorbic acid (VC) amount and GO concentration, were systematically explored. The prepared GA possessed outstanding adsorption property for organic liquid solvents (capacity achieved 307 times its own weight) and excellent physical features of flexible conductors, low density (3.4 mg/cm3), high porosity (95.4 %), mechanical stability (supports at least 1150 times its own weight), hydrophobicity (contact angle of 93°) and high energy density (0.477 mAh/cm2). Furthermore, the contribution of excellent light absorption, effective electron transfer, high surface area and CO bond made GA represent superior photocatalysis-persulfate activation performance for ciprofloxacin (CIP) degradation (85.5 %) for 60 min under sunlight. The removal rate of CIP still remained at 78.4 % after 5 cycle tests, indicating that GA possessed excellent stability. The flexible GA exhibited tremendous potential in environmental purification and flexible conductive material.