bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Vertical and Pinch Rolling on Residual Stress Distributions in Wire and Arc Additively Manufactured Components
Authors: Tangestani Reza , Farrahi Gholam Hossein , Shishegar Mehdi , Aghchehkandi Bahareh Pourbagher , Ganguly Supriyo , Mehmanparast Ali
Published: April 2020

Residual stresses are inherent in parts manufactured using the wire + arc additive manufacturing (WAAM) technique, resulting in unpredictable mechanical response and structural integrity (Colegrove et al.: J Mater Process Technol 213:1782-1791, 2013). An effective post-processing technique, which enhances the mechanical properties of WAAM parts, is rolling. This study investigates the vertical and pinch rolling effects on residual stress distribution in WAAM components. Initially, a WAAM model was created using a thermo-mechanical finite element modelling approach and validated against the experimental results. Subsequent to the validation of the model, the effect of the main parameters involved in vertical and pinch rolling processes, namely the rolling depth, the curvature depth of the roller, the roller shape, transversal displacement, rolling direction and roller thickness, was investigated. The results from this study show that the residual stress profile in the vertical rolling process applied on a WAAM wall can be enhanced by increasing the rolling depth and curvature depth of the roller. Moreover, it is shown that in the pinch rolling process, the residual stress profile is sensitive to the rolling direction and more compressive residual stresses can be induced into the wall by applying fewer passes of rolling using thicker rollers.
One anastomosis gastric bypass vs. Roux-en-Y gastric bypass, remedy for insufficient weight loss and weight regain after failed restrictive bariatric surgery
Authors: Poublon Nathan , Chidi Ibtissam , Bethlehem Martijn , Kuipers Ellen , Gadiot Ralph , Emous Marloes , van Det Marc , Dunkelgrun Martin , Biter Ulas , Apers Jan
Published: April 2020

Background

Failure occurs in up to 60% of the patients that were treated with primary restrictive bariatric operations such as Laparoscopic Adjustable Gastric Banding (LAGB), or restrictive/metabolic operations like Laparoscopic Sleeve Gastrectomy (LSG). Insufficient weight loss and weight regain are the most commonly reported reasons of failure. The aim of this retrospective multicenter study was to compare One Anastomosis Gastric Bypass (OAGB) to Roux-en-Y Gastric Bypass (RYGB) as a revisional procedure in terms of weight loss, procedure time, complication rate and morbidity.

Methods

491 patients operated on between 2012 and 2017 for failed restrictive surgery were included in this study (OAGB (n=185) or RYGB (n=306)). Failure was defined as total weight loss (TWL) less than 25%, excess weight loss (EWL) less than 50% and/or a remaining body mass index (BMI) larger than 40 kg/m2 at two years of follow up. Primary outcome measures were %TWL and % excess BMI loss (EBMIL) at 12, 24 and 36 months of follow-up. Secondary outcomes were procedure time, reduction of comorbidity, early and late complication rate, and mortality.

Results

%TWL was significantly larger in the OAGB group at 12 months (mean 24.1±9.8 vs. 21.9±9.7, p = 0.023) and 24 months (mean 23.9±11.7 vs. 20.5±11.2, p = 0.023) of follow-up. %EBMIL was significantly larger in the OAGB group at 12 months (mean 69.0±44.6 vs. 60.0±30.1, p = 0.014) and 24 months (mean 68.6±51.6 vs. 56.4±35.4, p = 0.025) of follow-up. Intra-abdominal complications (leakage, bleeding, intra-abdominal abscess and perforation) occurred less frequently after revisional OAGB (1.1% vs. 4.9%, p = 0.025). Surgical intervention for biliary reflux (5.4% vs. 0.3%, p < 0.001) was more prevalent in the OAGB group. Surgical intervention for internal herniation (0.0% vs. 4.9%, p = 0.002) was more prevalent in the RYGB group.

Conclusions

This study suggests that OAGB is superior to RYGB as a remedy for insufficient weight loss and weight regain after failed restrictive surgery with more weight loss and a lower early complication rate. To substantiate these findings, further research from prospective randomized controlled trials is needed.
Out-of-Home Mobility and Social Participation of Older People: a Photo-Based Ambulatory Assessment Study
Authors: Kahlert Daniela , Ehrhardt Niklas
Published: April 2020

Research has shown that social participation contributes to older people’s healthy ageing. Out-of-home mobility may promote higher levels of social participation among older people. However, mobility and social participation are sophisticated constructs. Social participation can be distinguished among different levels, such as being alone, being alone surrounded by others, interacting with others or engaging in activities together. Social participation and time spent in out-of-home-mobility can be difficult to remember and therefore difficult to assess. Picture-based ambulatory assessment provides valid and reliable information about people’s mobility as well as their level of participation with high ecological validity. The aim of the study was to investigate older people’s level of social participation and its association with high or low out-of-home mobility. In sum, 23072 pictures (mean per person = 2307; SD = 686.7) involving ten older people (mean age = 75.4 years; SD = 7.5 years) living in southwestern Germany were analysed. They were asked to wear a wearable camera for two consecutive days. Images were automatically captured every 15 seconds. Image analysis shows that study participants spent most of their time alone (at approximately 35% of analysed time). Out-of-home mobility was associated with higher levels of social participation, such as helping others (chi2 = 200,664, df = 5,p < .001). Picture-based ambulatory assessment can assist in the gathering of necessary sophisticated information that is difficult to assess via questionnaires or other similar methods.
Apolipoproteins, as the carrier proteins for lipids, are involved in the development of breast cancer
Authors: Zhou Y. , Luo G.
Published: April 2020

Apolipoproteins, the key components of lipoproteins, play vital roles in the combination and transportation of lipids. Numerous research articles have accumulated solid evidence that lipoproteins are closely related to various types of tumorigenesis. In this review, we focused on the associations between several apolipoproteins and breast carcinoma and distinguished the effects and significance of apolipoproteins in different locations to validate their roles in breast carcinoma development. For example, apoD and apoE in serum are viewed as risk factors for breast carcinoma. ApoD, apoE and apoA-I in mammary tissues inhibit tumor growth. Moreover, apoB, apoJ and apoA-I have the potential to function as diagnostic or prognostic markers in the clinic. ApoEdp and apoJ treatment on breast carcinoma could significantly restrict tumor growth. In general, the aim of this review was to further analyze the associations between some members of the apolipoprotein family and breast cancer.
Scenario analysis on abating industrial process greenhouse gas emissions from adipic acid production in China
Authors: Tong Qing , Lin Han-Yi , Qin Xu-Ying , Yan Run-Sheng , Guo Yue-Feng , Wei Xin-Yang
Published: April 2020

Adipic acid is an important petrochemical product, and its production process emits a high concentration of greenhouse gas N2O. This paper aims to provide quantitative references for relevant authorities to formulate greenhouse gas control roadmaps. The forecasting method of this paper is consistent with the published national inventory in terms of caliber. Based on the N2O abatement technical parameters of adipic acid and the production trend, this paper combines the scenario analysis and provides a measurement of comprehensive N2O abatement effect of the entire industry in China. Four future scenarios are assumed. The baseline scenario (BAUS) is a frozen scenario. Three emission abatement scenarios (ANAS, SNAS, and ENAS) are assumed under different strength of abatement driving parameters. The results show that China’s adipic acid production process can achieve increasingly significant N2O emission abatement effects. Compared to the baseline scenario, by 2030, the N2O emission abatements of the three emission abatement scenarios can reach 207–399 kt and the emission abatement ratios can reach 32.5%–62.6%. By 2050, the N2O emission abatements for the three emission abatement scenarios can reach 387–540 kt and the emission abatement ratios can reach 71.4%–99.6%.
Multiple Environmental Variables Affect Germination and Mortality of an Annual Salt Marsh Pioneer: Salicornia procumbens
Authors: van Regteren M. , Meesters E. H. , Baptist M. J. , de Groot A. V. , Bouma T. J. , Elschot K.
Published: April 2020

Salt marshes, providing numerous ecosystem services, are degrading worldwide. To effectively aid conservation and restoration efforts, increased knowledge on marsh expansion processes and the initial establishment of pioneer vegetation is essential. In this study, we disentangle environmental drivers that affect the lifecycle of the annual pioneer Salicornia procumbens at the salt marsh edge. We studied the effect of various environmental variables on the start of germination, germination success and mortality before seed-set in a field experiment in the Dutch Wadden Sea at Westhoek. Our results indicate that temperature and sedimentation inhibited the initiation of germination. Once germination occurred, higher precipitation rates increased germination success. In contrast, sedimentation rates above 0.5 mm day−1 halved germination success through burial of freshly sprouted seedlings. Unexpectedly, natural germination was low, indicating that seed availability may have been limited, despite a seed source nearby. Frequent inundation, extended periods without inundation (through desiccation of the soil) and a highly dynamic bed level increased mortality before seed-set. Consequently, bed-level dynamics (erosion, sedimentation and bed-level variation) impact seed production dually (decrease germination and increase mortality) and thus potentially reproduction success. A high seed reproduction is crucial for annuals, such as S. procumbens, to re-establish the following year. Next to advancing our general knowledge of natural salt marsh expansion, results in this study can also be used to assess the potential of a given site for salt marsh stimulation or restoration. Seed availability and local bed-level dynamics are key in the successful establishment of a salt marsh pioneer: Salicornia procumbens.
Lab-scale degradation of leather industry effluent and its reduction by Chlorella sp. SRD3 and Oscillatoria sp. SRD2: a bioremediation approach
Authors: Santhosh S. , Rajalakshmi A. M. , Navaneethakrishnan M. , Jenny Angel S. , Dhandapani R.
Published: April 2020

The present study focuses on treatment of tannery effluent samples using microalgae and isolated cyanobacteria. Different concentrations of both the effluent samples were treated with the algal isolates and a highest biomass of 0.295 g/l was attained in 50% of concentration on the 12th day in BHEL site. The biomass production in Walajapet site was found to be 0.387 g/l in the effluent treated with 50% of algae. The treated effluent was tested for growth and chlorophyll content was estimated, Chlorella sp. SRD3 showed higher chlorophyll content. The 50% treatment was processed at large-scale treatment in lab and biomass yield of 0.65 ± 0.04 g/l was achieved in BHEL site and 0.49 ± 0.028 g/l in Walajapet site. The treatment led to higher reduction rates in BOD and COD levels in treated effluents. The BOD in effluent from BHEL site was reduced to 83.41% and that from Walajapet site showed 87.46% reduction, whereas the COD values also showed 78% reduction. Based on the results, effluent sample serves as a medium for growth and bioremediation of tannery effluents by microalga, Chlorella sp. SRD3 revealed promising results which may prove efficient in the near future.
Evaluation of risk factors for secondary phimosis in children
Authors: Al-Mayoof Ali F. , Almushhadany Osama Esmaeel , Joda Ali E. , Mohammed Mohammed Kamil
Published: April 2020

ABSTRACT

Background:

Phimosis refers to inability to retract the prepuce, which is an indication of circumcision. Secondary phimosis is a late complication of circumcision that results from adhesion of redundant inner skin.

Aim:

This article evaluates the risk factors for secondary phimosis in children focusing on the age at circumcision, method used, and the person who performed the procedure, in addition to any post circumcision infections.

Setting:

Central Teaching Hospital of Pediatrics – Baghdad/Iraq.

Patients and method:

From May 2015 to June 2019, a total of 134 boys with secondary phimosis attended the outpatient pediatric surgery clinic. This group of patients was compared with a control group consisting of 154 boys. The two groups were compared regarding the age at circumcision, the circumciser, the method of circumcision, and any postoperative infection. In addition, patients with secondary phimosis were classified according to the grade of phimosis and evaluated with respect to risk factors.

Results:

The mean age at circumcision for the secondary phimosis and control groups were 9.0 ± 8.3 and 13.4 ± 11.2 months, respectively, with a significant P value (P = 0.001). A member of the nursing staff performed the circumcision in 89.5% of the secondary phimosis group, whereas a physician performed the circumcision in 67.5% of the control group, which was statistically significant. The circumcision in the secondary phimosis group was primarily performed using a bone cutter with thermal cautery (75%), whereas in the control group, the circumcision was primarily performed using a bone cutter with scalpel blade (65.5%) (P = 0.001). The grade of phimosis is significantly related to the method of circumcision and the age at circumcision.

Conclusion:

The incidence of secondary phimosis can be decreased if the circumcision is performed after the infancy period by an expert person and with the avoidance of thermal cautery.

Highlights:
Environmental Lapse Rate for High‐Resolution Land Surface Downscaling: An Application to ERA5
Authors: Dutra Emanuel , Muñoz‐Sabater Joaquín , Boussetta Souhail , Komori Takuya , Hirahara Shoji , Balsamo Gianpaolo
Published: April 2020

In this study we derive the environmental lapse rate (ELR) from vertical profiles of temperature in the lower troposphere, applying it to downscale air temperature of the new European Centre For Medium‐Range Weather Forecasts (ECMWF) reanalysis ERA5, which replaces ERA‐Interim (ERAI). We focus over the western U.S. region, a data‐rich area with observations of daily maximum and minimum temperature (Global Historical Climatology Network) and snow depth and soil temperature. Observations indicate an ELR of −4.5 K·km−1 in the region, lower than the commonly used −6.5 K·km−1. ERA5 ELR agrees with the observational estimates, with some overestimation in winter and limitations in the diurnal variability. The elevation correction of ERA5 temperature using different ELR showed the benefits of deriving ELR fields from ERA5 vertical profiles, when compared with a constant ELR. Simulations with the ECMWF land surface model, at 9‐km resolution, driven by ERA5 using different ELR corrections showed the added value of the methodology, but the impact of different ELR corrections is limited. However, the validity of the downscaling method in reducing temperature to station altitude suggests that there is sufficient generality for application at kilometer and subkilometer resolutions. By comparing the estimated representativity errors of observations with reanalysis, the improvements from ERAI to ERA5 are mainly visible in the random component of the error. Large systematic biases remain, which require further attention from the modeling and data assimilation, and limit the potential benefits of ELR corrections.
A Graceful Way to Study Daily Water Storage on Land
Authors: Shultz David
Published: April 2020

A new analysis technique could help scientists improve the temporal resolution of satellite gravity data and see trends in terrestrial water storage and movement in near real time.
Whistler Mode Quasiperiodic Emissions: Contrasting Van Allen Probes and DEMETER Occurrence Rates
Authors: Němec F. , Santolík O. , Hospodarsky G. B. , Hajoš M. , Demekhov A. G. , Kurth W. S. , Parrot M. , Hartley D. P.
Published: April 2020

Quasiperiodic emissions are magnetospheric whistler mode waves at frequencies between about 0.5 and 4 kHz which exhibit a nearly periodic time modulation of the wave intensity. We use large data sets of events observed by the Van Allen Probes in the equatorial region at larger radial distances and by the low‐altitude DEMETER spacecraft. While Van Allen Probes observe the events at all local times and longitudes, DEMETER observations are limited nearly exclusively to the daytime and significantly less frequent at the longitudes of the South Atlantic Anomaly. Further, while the events observed by Van Allen Probes are smoothly distributed over seasons with only mild maxima in spring/autumn, DEMETER occurrence rate has a single pronounced minimum in July. The apparent inconsistency is explained by considering a nondipolar Earth's magnetic field and significant background wave intensities which in these cases prevent the quasiperiodic events from being identified in DEMETER data.
A Revisit of Direct and Diffuse Solar Radiation in China Based on Homogeneous Surface Observations: Climatology, Trends, and Their Probable Causes
Authors: Wang Yawen , Yang Su , Sanchez‐Lorenzo Arturo , Yuan Wenping , Wild Martin
Published: April 2020

Increasing energy and food demands require an understanding of not only the availability and variability of total solar radiation (R) but also its partitioning into direct (Rd) and diffuse (Rf) components, which are key elements for solar power generation and plant photosynthesis, respectively. Potential inhomogeneities in surface solar radiation observations, however, add uncertainties to the published patterns and trends of Rd and Rf over China. To exclude inhomogeneous time series and outliers, a data quality control process has been applied to the surface observations of Rd and Rf. The homogeneous data show that, in response to the global dimming and brightening phenomena in R, decadal changes can also be observed in the Rd and Rf trends over China with the actual transition occurring in the mid‐2000s. Since the 1960s, Rd dimming has mainly distributed over eastern China with intensive anthropogenic activities, with recoveries especially from 2008 onward over regions with high Rd energy potential. Rf, on the other hand, had further enhanced since the 1960s especially over the high Rf proportion areas but has decreased in the recent decade over the northern region. The summer season shows the most significant decadal trends in Rd and Rf. Under clear‐sky conditions, that is, ruling out cloud effects, the transitions in Rd and Rf trends become more remarkable, pointing to atmospheric aerosols as the main driving force. In addition, dramatic Rd and Rf variations are observed in the subsequent years after large volcanic eruptions. The varying Rd and Rf proportions are in line with recent governmental control on SO2 emissions over China.
Addition of an online, validated family history questionnaire to the Dutch FIT-based screening programme did not improve its diagnostic yield
Authors: Roos Victorine H. , Kallenberg Frank G. J. , van der Vlugt Manon , Bongers Evelien J. C. , Aalfs Cora M. , Bossuyt Patrick M. M. , Dekker Evelien
Published: April 2020

Background

Faecal immunochemical testing (FIT) is suboptimal in detecting advanced neoplasia (AN). To increase the sensitivity and yield of a FIT-based screening programme, FIT could be combined with risk factors for AN. We evaluated the incremental yield of adding a family history questionnaire (FHQ) on colorectal cancer (CRC) and Lynch syndrome-associated tumours to the Dutch FIT-based screening programme.

Methods

Six thousand screen-naive individuals, aged 59–75 years, were invited to complete a FIT (FOB-Gold, cut-off 47 µg Hb/g faeces) and a validated online FHQ. Participants with a positive FIT and/or positive FHQ, confirmed after genetic counselling, were referred for colonoscopy. Yield of detecting AN per 1000 invitees for the combined strategy was compared with the FIT-only strategy.

Results

Of the 5979 invitees, 1952 (32.6%) completed the FIT only, 2379 (39.8%) completed both the FIT and FHQ and 95 (1.6%) completed the FHQ only. Addition of the FHQ to FIT-based screening resulted in one extra case of AN detected after 16 additional colonoscopies, resulting in a yield of 19.6 (95% CI, 16.4–23.5) for the combined strategy versus 19.5 (95% CI, 16.3–23.3) for the FIT-only strategy (p = 1.0).

Conclusions

The addition of an FHQ to one round of FIT screening did not increase the detection of AN compared with FIT only (ClinicalTrials.gov NCT02698462).
Hopfield learning‐based and non‐linear programming methods for resource allocation in OCDMA networks
Authors: Pendeza Martinez Cristiane A. , Durand Fábio Renan , Abrao Taufik , Goedtel Alessandro
Published: April 2020

This study proposes the deployment of the Hopfield neural network (H‐NN) approach to optimally assign power in optical code division multiple access (OCDMA) systems. Figures of merit such as the feasibility of solutions and complexity are compared with the classical power allocation methods found in the literature, such as sequential quadratic programming (SQP) and augmented Lagrangian method. The analysed methods are used to solve constrained non‐linear optimisation problems in the context of resource allocation for optical networks, especially to deal with energy efficiency in OCDMA networks. The promising performance‐complexity trade‐off of the modified H‐NN is demonstrated through numerical results performed in comparison with classic methods for general problems in non‐linear programming. The evaluation is carried out considering challenging OCDMA networks in which different levels of service quality required were considered for large numbers of optical users. The numerical results demonstrated that the three power allocation methods attain suitable convergence for different network sizes, while both the mH‐NN and SQP methods achieve suitable equilibrium with less complexity.
Baseline parity‐check matrix for iterative soft‐decision decoding of binary cyclic codes
Authors: Babalola Oluwaseyi P. , Ogundile Olayinka O. , Versfeld Daniel Jaco J.
Published: April 2020

Belief propagation (BP) is a soft‐decision (SD) decoder that is commonly used to obtain near‐optimal decoding performance for linear codes defined over sparse parity‐check matrix. Nevertheless, the BP yields poor performance when used in the decoding of algebraic block codes, usually described by a dense parity‐check matrix. Hence, enhanced BP decoders transform the parity check matrix of such codes at each iteration for efficient decoding. In this article, the performance of the transformed parity‐check matrix of the iterative SD decoder is analysed for the class of binary cyclic codes using a perfect knowledge model (PKM). The PKM computes a list of candidate matrices and selects a baseline parity‐check matrix according to a distance metric. The selected matrix is optimal since it minimizes the probability of error over various choices in the list. Results show that, for a given channel condition, the conventional transformed matrix obtained by Gaussian elimination is sub‐optimal and does not necessarily contain unitary weighted columns at corresponding columns of the unreliable bits. Moreover, PKM can be used to verify the performances of newly developed iterative SD decoders for binary cyclic codes based on parity‐check equations instead of maximum‐likelihood decoding.
Robust finite‐frequency filter design for linear uncertain systems using polynomially parameter‐dependent approach
Authors: Ren Yingying , Li Qing , Ding Da‐Wei , Kang Wen
Published: April 2020

This study investigates the problem of robust filter design for continuous‐time linear uncertain systems affected by external noises in finite‐frequency (FF) ranges. The objective is to design an admissible filter guaranteeing asymptotic stability of the filtering error system with a prescribed FF noise attenuation level. To this end, homogenous polynomially parameter‐dependent Lyapunov functions are used to assess the stability of the filtering error system, and robust FF bounded realness lemma is used to describe the noise attenuation specifications. Polynomially parameter‐dependent matrices and some scalars are introduced to facilitate filter design and reduce conservatism. Moreover, a sequential convex approximation method is used to replace the non‐convex constrained set with a convex feasible one. On this basis, an iterative algorithm is developed to calculate the filter parameters. It is demonstrated that the proposed robust FF filter can achieve a better noise attenuation performance in the FF range than the existing ones in the literature. An example about F‐18 aircraft model is given to illustrate the effectiveness of the proposed method.
Node‐to‐node bipartite consensus of multi‐agent systems with disturbances
Authors: Hu Aihua , Park Ju H. , Cao Jinde
Published: April 2020

This study presents a novel concept of consensus for multi‐agent systems with a two‐layer framework, namely, the node‐to‐node bipartite consensus. The agents are divided into the virtual leaders and followers, and the signed graph representing communication channels of followers is supposed to be structurally balanced. Moreover, only a small part of the followers are pinned by their corresponding leaders. In addition, the proposed control is subjected to Gaussian disturbances or norm‐bounded disturbances, and two extended forms of node‐to‐node bipartite consensus are correspondingly defined. By utilising the signed graph theory, the M ‐matrix theory, and the Lyapunov function approach, the consensus error between an arbitrary follower and its leader is proved to converge to zero in the mean square sense or to be ultimately bounded. The proposed conditions for consensus mainly depend on the selection of pinned followers and the coupling strength in each layer. Finally, the theoretical results are illustrated by detailed numerical examples.
State observer design method for a class of non‐linear systems
Authors: Arezki Hasni , Zemouche Ali , Bedouhene Fazia , Alessandri Angelo
Published: April 2020

In this study, the authors develop a new high‐gain observer design method for non‐linear systems. This new design provides a lower gain compared to both the high‐gain and the enhanced high‐gain observer. The idea is to combine the improved high‐gain methodology with the linear matrix inequality based observer design technique to build a more general observer that allows one to exploit the benefits of both approaches. A numerical example is given to show the effectiveness of the proposed observer with different values of the Lipschitz constant and of the compromise index.
Green synthesise of CuO@Fe3O4@Xantan nanocomposites and its application in enhanced oil recovery by considering IFT and wettability behaviours
Authors: Manshad Abbas Khaksar , Ali Jagar A. , Imani Irfan , Sajadi S. Mohammad , Tayeb Ubaid Nabil A. , Keshavarz Alireza
Published: April 2020

Enhanced oil recovery (EOR) makes use of various chemical processes to extract additional oil from reservoirs, often already under production. In this study, authors investigated the role of the CuO@Fe3O4@xanthan nanocomposite (NCs) in EOR by the focus of the interfacial tension (IFT) and wettability alteration mechanisms. This NCs is synthesized from Artocarpus altilis extract using a simple, economical and green method. The prepared NCs is identified using X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Nanofluids are prepared from dispersing the synthesised NCs in water at different concentrations in order to be used in the density, viscosity, conductivity, IFT and contact angle measurements. The results showed an improvement in the values of IFT and contact angle. The IFT of oil/water is increased from 22 to 24 mN/m with increasing the concentration of the NCs from 250 to 2000 ppm. While, the wettability of the carbonate rock is remained water‐wet, wherein the contact angle is raised from 28° to 58° with increasing the NCs concetration from 250 to 2000 ppm. Overall, the IFT and contact angle are only reduced when 250 ppm NCs was added to water from 28.3 mN/m and 132.6° mN/m to 22 and 34.5°.
Das augenärztliche Gutachten in unterschiedlichen Rechtsgebieten
Authors: Rohrschneider Klaus , Tost Frank
Published: April 2020

Die augenärztliche Begutachtung unterscheidet sich in den verschiedenen Rechtsgebieten deutlich, so gelten unterschiedliche Kausalitäten und Beweismaßstäbe, und die Bewertung muss unterschiedlichen Maßstäben folgen. Für die 3 wichtigen Teilbereiche der Privaten und der Gesetzlichen Unfallversicherung sowie dem Schwerbehindertenrecht bzw. dem sozialen Entschädigungsrecht existieren abstrakte tabellarische Vorgaben. Die Grundlagen der Begutachtung in diesen Rechtsgebieten werden vergleichend dargestellt, dabei wird besonders auf die Kausalität eingegangen.
Modeling of microporosity formation and hydrogen concentration evolution during solidification of an Al–Si alloy*
Authors: Zhang Qingyu , Sun Dongke , Zhang Shunhu , Wang Hui , Zhu Mingfang
Published: April 2020

We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum–silicon (Al–Si) alloy. The applied lattice Boltzmann-cellular automaton-finite difference model incorporates the physical mechanisms of solute and hydrogen partitioning on the solid/liquid interface, as well as the transports of solute and hydrogen. After the quantitative validation by the simulation of capillary intrusion, the model is utilized to investigate the growth of the equiaxed dendrites and hydrogen porosity formation for an Al–(5 wt.%)Si alloy under different solidification conditions. The simulation data reveal that the gas pores favorably nucleate in the corners surrounded by the nearby dendrite arms. Then, the gas pores grow in a competitive mode. With the cooling rate increasing, the competition among different growing gas pores is found to be hindered, which accordingly increases the pore number density in the final solidification microstructure. In the late solidification stage, even though the solid fraction is increasing, the mean concentration of hydrogen in the residue melt tends to be constant, corresponding to a dynamic equilibrium state of hydrogen concentration in liquid. As the cooling rate increases or the initial hydrogen concentration decreases, the temperature of gas pore nucleation, the porosity fraction, and the mean porosity size decrease, whilst the mean hydrogen concentration in liquid increases in the late solidification stage. The simulated data present identical trends with the experimental results reported in literature.
Photoelectron momentum distributions of single-photon ionization under a pair of elliptically polarized attosecond laser pulses*
Authors: Cui Hui-Fang , Miao Xiang-Yang
Published: April 2020

The attosecond ionization dynamics of atoms has attracted extensive attention in these days. However, the role of the initial state is not clearly understood. To address this question, we perform simulations on the neon atom and its model atom with different initial states by numerically solving the corresponding two-dimensional time-dependent Schrödinger equations. We theoretically investigate atomic photoelectron momentum distributions (PMDs) by a pair of elliptically polarized attosecond laser pulses. We find that the PMD is sensitive not only to the ellipticities of the pulses, the relative helicity, and time delay of the pulses, but also to the symmetry of the initial electronic states. Results are analyzed by the first-order time-dependent perturbation theory (TDPT) and offer a new tool for detecting the rotation direction of the ring currents.
Diffusion and collective motion of rotlets in 2D space*
Authors: Matsunaga Daiki , Chodo Takumi , Kawai Takuma
Published: April 2020

We investigate the collective motion of rotlets that are placed in a single plane. Due to the hydrodynamic interactions, the particles move through the two-dimensional (2D) plane and we analyze these diffusive motions. By analyzing the scaling of the values, we predict that the diffusion coefficient scales with ϕ
0.5, the average velocity with ϕ, and relaxation time of the velocity autocorrelation function with ϕ
–1.5, where ϕ is the area fraction of the particles. In this paper, we find that the predicted scaling could be seen only when the initial particle position is homogeneous. The particle collective motions are different by starting the simulation from random initial positions, and the diffusion coefficient is the largest at a minimum volume fraction of our parameter range, ϕ = 0.05. The deviations based on two initial positions can be explained by the frequency of the collision events. The particles collide during their movements and the inter-particle distances gradually increase. When the area fraction is large, the particles will result in relatively homogeneous configurations regardless of the initial positions because of many collision events. When the area fraction is small (ϕ < 0.25), on the other hand, two initial positions would fall into different local solutions because the rare collision events would not modify the inter-particle distances drastically. By starting from the homogeneous initial positions, the particles show the maximum diffusion coefficient at ϕ ≈ 0.20. The diffusion coefficient starts to decrease from this area fraction because the particles start to collide and hinder each other from a critical fraction ∼ 23 %. We believe our current work contributes to a basic understanding of the collective motion of rotating units.
575-fs passively mode-locked Yb:CaF2 ceramic laser*
Authors: Wang Cong , Hao Qian-Qian , Li Wei-Wei , Huang Hai-Jun , Wang Shao-Zhao , Jiang Da-Peng , Liu Jie , Mei Bing-Chu , Su Liang-Bi
Published: April 2020

A Yb-doped CaF2 transparent ceramics was successfully fabricated by the hot-pressed method and its laser characteristics were studied. A broad tuning performance and mode-locked laser operation were demonstrated in this ceramics for the first time, to our best knowledge. A 60-nm continuous-wavelength tunable laser from 1019 nm to 1079 nm was obtained with a birefringent filter. By employing a semiconductor saturable absorber mirror without additional dispersion compensation elements, a continuous-wave mode-locked laser with pulse duration as short as 575 fs was delivered, at a central wavelength of 1048.5 nm. The oscillator is operated under a repetition rate of 55 MHz. These results indicate that the Yb:CaF2 transparent ceramics is an ideal candidate for the development of ultrafast lasers in the near-infrared regime.
The drying of liquid droplets*
Authors: Jiang Zechao , Yang Xiuyuan , Wu Mengmeng , Man Xingkun
Published: April 2020

The drying of liquid droplets is a common phenomenon in daily life, and has long attracted special interest in scientific research. We propose a simple model to quantify the shape evolution of drying droplets. The model takes into account the friction constant between the contact line (CL) and the substrate, the capillary forces, and the evaporation rate. Two typical evaporation processes observed in experiments, i.e., the constant contact radius (CCR) and the constant contact angle (CCA), are demonstrated by the model. Moreover, the simple model shows complicated evaporation dynamics, for example, the CL first spreads and then recedes during evaporation. Analytical models of no evaporation, CCR, and CCA cases are given, respectively. The scaling law of the CL or the contact angle as a function of time obtained by analytical model is consistent with the full numerical model, and they are all subjected to experimental tests. The general model facilitates a quantitative understanding of the physical mechanism underlying the drying of liquid droplets.
Comparative evaluation of proximate composition and vitamin C of Physalis angulata Linn and Physalis peruviana
Linn in West Java, Indonesia
Authors: Iwansyah AC , Surahman D N , Hidayat D D , Luthfiyanti R , Indriati A , Ardiansyah C E
Published: April 2020

This study aimed to evaluate the proximate and vitamin C of Physalis. Two species of Physalis, namely, P. angulata L. and P. peruviana L., used as models for a comparative study. Proximate composition, fiber, and vitamin C of all part of Physalis, i.e., leaf, stem, bud, and fruit of Physalis were analyzed. Physalis angulata collected from Pagaden subdistrict (latitude: 6030’24” S, longitude: 107048’74”E, elevation: 55 MAMSL) Subang District, West Java Province, and Physalis peruviana collected from Pamulihan subdistrict (latitude: 6052’27.06”S, longitude: 107049’24.95”E, elevation: 947 MAMSL), Sumedang district, West Java Province. The results of the study showed that the existence of proximate composition and vitamin C in plant shoot of P. angulata and P. peruviana relatively evenly spread. The proximate composition and vitamin C of Physalis angulata had the same pattern as compared to that of Physalis peruviana. The results of paired sample test showed that there were no significant differences in proximate composition and vitamin C between Physalis angulata and Physalis peruviana.
Characterization of fiber fraction, physical and chemical properties of coffee flour (Coffea sp.) as functional foodstuff for diabetes mellitus patient
Authors: Mindarti S , Zalizar L , Damat  , Saati E A , Fajriani S
Published: April 2020

Coffee pulp is solid waste from coffee processing, but unfortunately, it has not been utilized optimally, particularly for foods. Objective of the research was to study characterization of fiber fraction, physical and chemical properties of coffee flour as functional dietary material, which is rich in fiber to reduce blood glucose level for diabetes mellitus patients. The research used Arabica and Robusta coffee pulps. Results of the research showed that characterization of fiber fraction for Arabica has soluble dietary fiber 4.78% (db); 4.30% (wb) higher 0.63% (db); 0.55% (wb) in comparison with Robusta. However, the insoluble dietary fiber is 69.16% (db); 62.24% (wb) and total dietary fiber is 73.32% (db); 65.98% (wb) for Robusta is higher 10.78% (db); 9.82% (wb) insoluble dietary fiber and 10.15% (db); 9.26% (wb) total dietary fiber in comparison with Arabica. Granule shape of the flour for Arabica and Robusta have uneven surfaces and diverse sizes of granule. Arabica flour granules are smaller, 12.8-49.8 µm, than Robusta, 48.8-66.8 µm. Testing the chemical properties showed fat level was 4.05% (wb); 4.55% (db), water 10.96% (wb) and ash 9.35% (wb); 10.50% (db) for Arabica are higher 0.08% (wb); 0.12%(db) fat, 0.66% (wb) water and 0.81% (wb); 0.99% (db) ash. However, carbohydrate level was 62.78% (wb); 70% (db) and protein 14.41% (wb); 16.06% (db) for Robusta was higher 1.24% (wb); 0.88% (db) carbohydrate and 0.31% (wb); 0.23% (db) protein in comparison with Arabica. Coffee flour of Arabica has better characterization for fiber fraction, physical and chemical properties, in comparison with Robusta, due to it has higher soluble dietary fiber (SDF) and smaller flour granules, which are potential as functional foodstuff for diabetes mellitus patient.
Single starter Lactobacillus plantarum for modified cassava flour (mocaf) fermentation
Authors: Damayanti E , Kurniadi M , Helmi R L , Frediansyah A
Published: April 2020

Modified fermentation of cassava to produce modified cassava flour (mocaf) is generally used spontaneous fermentation or used mixed culture as starter. Mixed culture starter application in mocaf fermentation still has limitations because it requires a large number of microbial species and a more complex starter medium. In this study, optimization of single starter lactic acid bacteria (LAB) Lactobacillus plantarum formulation was carried out to obtain mocaf products. The eight-month cassava (110.20 ± 6.48 ppm of HCN content ) was obtained from the local market in Gunungkidul, DI. Yogyakarta, Indonesia. We used general mocaf processing, including stripping, slicing, fermenting, rinsing, drying, milling, and sieving. The starter formula including A : L. plantarum FNCC 0027 in 5% skim milk media + 0.2 % glucose and B: L. plantarum FNCC 0027 in 5% skim milk media without glucose. LAB total and pH were measured during fermentation process. Carbohydrate and HCN content of mocaf product were analysed. Carbohydrate content of mocaf were 97.34 ± 3.76 % and 96.78 ± 4.49 % whereas the HCN of mocaf products were 9.79 ± 0.08 ppm and 13.16 ± 0.48 ppm and reduction percentage of HCN content were 91.11 ± 0.11 and 88.06 ± 1.32 for starter A and starter B, respectively. Statistical analysis using T test showed that there is no sigficanlty different between starter with and without glucose addtition. For single culture application, starter L. plantarum FNCC 0027 in 5% skims milk + 0.2 % glucose resulted the better mocaf quality.
The effect of time, pH and solvent composition on cocoa shell polyphenol extraction and its antioxidant activity: response surface method approach
Authors: Wiyono T , Nurhayati R , Herawati E R N , Laila U
Published: April 2020

Cocoa is a high source of dietary polyphenols that provide health benefits to the body. Unfortunately, cocoa outer parts (fruit peel, bean shell and sludge cacao) during processing of cocoa are generally disposed of as waste. The aim of this study was to evaluate the optimum condition for polyphenols extraction of cocoa shell. The optimization was designed using Response Surface Method with three independent factors i.e. percent of ethanol, time of ultrasonic irradiation, and pH. Three parameters were observed i.e. total phenolic and flavonoid content, and antioxidant activity. The results shown that the ethanol composition, time of sonication, and pH of the solvent influencing effectiveness of polyphenol extraction with optimum conditions of ethanol content of 66.56%, sonication duration 33.5 minutes, and pH 1.34.
Protein isolation of Pterois volitans venomous with a heating process for antibacterial activity assay
Authors: Sommeng A N , Riswandha F , Ginting M J , Pebriani S , Sahlan M , Hermansyah H , Wijanarko A
Published: April 2020

Pterois volitans is an invasive native predatory fish species in the Indo-Pacific ocean that disrupt the food chain and damage coral reefs which cause ecosystem imbalances. These fish have venomous spines that made them inedible and avoided by a predator. Due to its rapid growth, utilization of this venom can be useful along with controlling the population. Recent studies show the benefits of phospholipase A2, which is a protein compound that contained in the venom has antibacterial activity and expected to be an antibacterial agent. In this study, we used heating and gradual purification to obtain the optimum concentration of Phospholipase A2. The protein isolates were analyzed using the Marinetti method, determination of concentration by Lowry test, identification of protein with SDS-Page, and the antibacterial activity test using agar diffusion. The results of phospholipase A2 obtained from the extract of P. volitans venom by purification method ammonium sulfate at 80% saturation with a heating time of 35 minutes had a specific enzyme activity of 0.0206 units / µg and can inhibit E. coli bacteria 98.81% and Salmonella sp. inhibit 89.28% with a concentration of 3.77 µg / ml.
Characterisation of physical, mechanical and colour properties of Muntingia calabura fruits
Authors: Indriati A , Hidayat D D , Andriansyah R C E , Iwansyah A C , Surahman D N
Published: April 2020

Physical, mechanical and colour properties are necessary parameters in the handling and processing of Muntingia calabura fruits. The study aimed to form physical, mechanical and colour database for Muntingia calabura fruits. Results of the study found that the polar and equatorial diameter ranged from 14.30±0.99 mm and 15.51±0.98 mm, respectively. The weight and the volume were 2.49±0.39 g and 1.12±0.21 cm3, respectively. The particle density, bulk density and porosity ranged 0.97±0,10 g/cm3, 0.57±0.03 gr/cm3 and 40.90±6.59% respectively. The average skin strength and elasticity of the average moisture content of 80.79 ± 0.50 % were 309.60±80.89 g-forces and 38.83±1.63 mm, respectively. The angle of repose on the surface of the acrylic, aluminium, stainless steel and plywood was 23.45±5.390, 24.20±4.770, 25.66±5.000 and 25.93±7.850 respectively with the static friction of 0.44±0.12, 0.45±0.10, 0.49±0.11, and 0.50±0.17 respectively. The coordinate CIE L*a*b* c* and h* of the average colour of samples was 44.914±5.011, 30.274±4.055, 10.460±2.787, 32.288±2.722 and 0.008±0.004.
Antibacterial activities of biocomposite plastic-based phenolic acids-grafted chitosan and sugar palm starch (Arenga pinata)
Authors: Anwar M , Istiqomah L , Ekaningrum M , Yembise D
Published: April 2020

Antibacterial activity of biocomposite plastics based sugar palm starch (SPS) and phenolic acid-grafted chitosan has been investigated. The various type of active compounds (ferulic acid-grafted chitosan, caffeic acid-grafted chitosan, and coumaric acid-grafted chitosan) was synthesis by free radical method and was evaluated by using FTIR and calculate the degree of substitution by using Folin-Ciocalteu procedure. The biocomposite plastics were made by combined SPS with glycerol, cellulose, zeolite, and active compounds (phenolic acid-grafted chitosan). Morphological structures were analyzed by using SEM, and antibacterial activities were evaluated by using agar diffusion method. It was found that the grafting reaction of phenolic acids was not improved the antibacterial activities. The biocomposite plastics impregnated with grafted products were showed no clear zone.
Cellulose acetate production from paddy rice straw and oil palm empty fruit bunch: trichloroacetate catalyst
Authors: Maryana R , Anwar M , Hasanah S U , Fitriana E , Suwanto A , Rizal W A
Published: April 2020

The utilization of non-wood biomass for fuels and chemicals production is widely studied in recent years. This paper reported the application of trichloroacetate as catalyst in the production of cellulose acetate from paddy (Oriza sativa) rice straw and oil palm (Elaeis guineensis) empty fruit bunch (EFB). Firstly, pre-treatment by using H2O in acidic condition was carried out prior to the soda pulping by using NaOH 10%, solid to liquid ratio 1:7. The pre-treatment and pulping aim to separate cellulose from lignin and hemicellulose. Furthermore, in order to purify the cellulose, bleaching was applied to the pulps by using NaClO2 0.5% and H2O2 10%. Finally, the paddy rice straw pulp and oil palm EFB pulp were subjected to the acetylation by using acetic anhydride as acetylating agent in CH3COOH condition with catalyst CCl3COOH and H2SO4. The analysis results by using Fourier-transform infrared spectroscopy showed that C=O stretching from cellulose acetate at around 1730 cm−1. Furthermore, the morphological surface and crystallinity of the raw materials and products was analysed by using scanning electron microscopy and X-ray diffraction, respectively. The acetylated cellulose diameter and cristallinity decreased after the acetylation reaction.