bluuebunny/crossref_metadata_2025 huggingface dataset:
Switchable magnetic frustration in buckyball nanoarchitectures
Authors: Cheenikundil Rajgowrav , Hertel Riccardo
Published: May 2021

Recent progress in nanofabrication has led to the emergence of three-dimensional magnetic nanostructures as a vibrant field of research. This includes the study of three-dimensional arrays of interconnected magnetic nanowires with tunable artificial spin-ice properties. Prominent examples of such structures are magnetic buckyball nanoarchitectures, which consist of ferromagnetic nanowires connected at vertex positions corresponding to those of a C60 molecule. These structures can be regarded as prototypes for the study of the transition from two- to three-dimensional spin-ice lattices. In spite of their significance for three-dimensional nanomagnetism, little is known about the micromagnetic properties of buckyball nanostructures. By means of finite-element micromagnetic simulations, we investigate the magnetization structures and the hysteretic properties of several sub-micron-sized magnetic buckyballs. Similar to ordinary artificial spin-ice lattices, the array can be magnetized in a variety of zero-field states with vertices exhibiting different degrees of magnetic frustration. Remarkably, and unlike planar geometries, magnetically frustrated states can be reversibly created and dissolved by applying an external magnetic field. This easiness to insert and remove defect-like magnetic charges, made possible by the angle-selectivity of the field-induced switching of individual nanowires, demonstrates a potentially significant advantage of three-dimensional nanomagnetism compared to planar geometries. The control provided by the ability to switch between ice-rule obeying and magnetically frustrated structures could be an important feature of future applications, including magnonic devices exploiting differences in the fundamental frequencies of these configurations.
Angular dependence of spin wave resonance in FeNi–MgO granular film
Authors: Cai Yongyong , Feng Hongmei , Song Chengkun , Niu Yabin , Ye Yuchen , Wu Huiliang , Wang Jianbo , Liu Qingfang
Published: May 2021

We study the angle dependence of the spin wave resonance spectra in FeNi–MgO granular films fabricated by magnetron sputtering, using ferromagnetic resonance technology. Seven Portis-type spin resonances with the same magnetic field spacing are observed when the magnetic field is perpendicular to the film. By varying the field angle θH, we find that there are at least two resonance modes at θH = 14°, indicating that the critical angle θc of the ferromagnetic resonance mode is in the range of 14°–15°. Furthermore, we obtained the exchange stiffness constant and distortion parameter through the surface inhomogeneity model and the volume inhomogeneity model. Moreover, in order to figure out the types of spin wave, we also investigate the dependence of spin wave resonance spectra on temperature, which reveals an excitation of the perpendicular spin standing wave.
Fragmentation and structural transitions of few-layer graphene under high shear stress
Authors: Yuan Mingzhi , Susilo Resta A. , Li Shujia , Feng Jiajia , Benavides Vicente , Chen Jian , Soldatov Alexander V. , Chen Bin
Published: May 2021

A key factor that determines the mechanical and electrical performance of graphene-based materials and devices is how graphene behaves under extreme conditions, yet the response of few-layer graphene to high shear stress has not been investigated experimentally. Here we applied high pressure and shear to graphene powder using a rotational diamond anvil cell and studied the recovered sample with multiple means of characterization. Sustaining high pressure and shear, graphene breaks into nanometer-long clusters with generation of large number of defects. At a certain stress level, it transforms to amorphous state and carbon onions. The reduction of infrared reflectivity in the severely sheared phase indicates the decrease in conductivity. Our results unveil the shear sensitive nature of graphene, point out the effects of shear on its physical properties, and provide a potential method to manipulate this promising material.
Solar-driven thermal-wind synergistic effect on laser-textured superhydrophilic copper foam architectures for ultrahigh efficient vapor generation
Authors: Yin Kai , Wu Zhipeng , Wu Junrui , Zhu Zhuo , Zhang Fan , Duan Ji-An
Published: May 2021

Solar-driven vapor generation is a sustainable and environmentally friendly method for water purification. Despite recent progress on photothermal steam generation, the rate of vapor generation remains low. Here, we enhance the vapor generation rate by combining solar-driven thermal and wind effects on a femtosecond-laser-textured superhydrophilic copper foam surface. Significant solar power can be absorbed and transformed into heat on the treated surface. This solar power can also be converted into electric power to generate wind to further accelerate steam generation. The upper superhydrophilic foam surface facilitates the continuous supply of water. A pre-wetted polyurethane sponge minimizes heat loss by preventing direct contact between the heated foam and bulk water. The as-prepared evaporator achieved a water evaporation rate of ∼7.6 kg m−2 h−1 under one sun irradiation (1 kW m−2) at a wind speed of 3 m s−1. This is a promising technology for enhancing water evaporation rates in seawater desalination and wastewater treatment applications.
A solution to the permalloy problem—A micromagnetic analysis with magnetostriction
Authors: Renuka Balakrishna Ananya , James Richard D.
Published: May 2021

A long-standing puzzle in the understanding of magnetic materials is the “Permalloy problem,” i.e., why the particular composition of Permalloy, Fe21.5Ni78.5, achieves a dramatic drop in hysteresis and concomitant increase in initial permeability, while its material constants show no obvious signal of this behavior. In fact, the anisotropy constant κ1 and the magnetostriction constants λ100,λ111 all vanish at various nearby, but distinctly different, compositions than Fe21.5Ni78.5. These compositions are in fact outside the compositional region where the main drop in hysteresis occurs. We use our newly developed coercivity tool [A. Renuka Balakrishna and R. D. James, Acta Mater. 208, 116697 (2021)] to identify a delicate balance between local instabilities and magnetic material constants that lead to a dramatic decrease in coercivity at the Permalloy composition Fe21.5Ni78.5. Our results demonstrate that specific values of magnetostriction constants and anisotropy constants are necessary for the dramatic drop of hysteresis at 78.5% Ni. Our findings are in agreement with the Permalloy experiments and provide theoretical guidance for the development of other low hysteresis magnetic alloys.
Distinctive features of the charge density wave collective motion driven by Hall electric field in NbSe3
Authors: Frolov A. V. , Orlov A. P. , Gay F. , Sinchenko A. A. , Monceau P.
Published: May 2021

We present a comparative study of the charge density wave (CDW) sliding at low temperatures in NbSe3 between two configurations: the conventional one with the current applied along the chain axis and that, the CDW being driven by the Hall electric field, with the current applied along micrometer-sized bridge-type structures cut perpendicular to the chain axis. In this Hall bar configuration, nonlinear properties can be easily extended to much lower temperatures. The threshold electric field, Et, for CDW depinning is very sharp and has been measured down to 0.1 mK. It is found that Et becomes temperature independent below T≈4.2 K, which suggests a crossover from thermal fluctuations to a tunneling mechanism for CDW depinning.
2D electrons floating on a suspended atomically thin dielectric
Authors: Vasko F. T.
Published: May 2021

The 2D electrons trapped in vacuum near the atomically thin dielectric (ATD, mono- or N-layer film of h-BN or transition metal dichalcogenide) are considered. ATD is suspended above the back gate and forms the capacitor, which is controlled by the biased voltage determining 2D concentration, n2D. It is found that the leakage current through ATD is negligible, and the effect of the polarizability of ATD is weak if N≤5. At temperatures T=0.1–15 K and n2D=5×108–1010cm−2, one deals with the Boltzmann liquid having a macroscopic thickness of ∼100 A. Due to the bending of ATD, the quadratic dispersion law of the flexural vibrations is transformed into the linear one at small wave vectors. The scattering processes of the electrons caused by these phonons or the monolayer islands on ATD are examined and the momentum and energy relaxation rates are analyzed based on the corresponding balance equations. The momentum relaxation times vary over orders of magnitude in the above region (T, n2D) and N. The response may change from the polaron transport, for a perfect single-layer ATD at low T and high n2D, to the high-mobility (≥107cm2/Vs) regime at high T and low n2D. The quasi-elastic energy relaxation due to phonon-induced scattering is considered, and the conditions for the heating of electrons by a weak in-plane electric field are found.
Should solar geoengineering be part of how humanity counters climate change?
Authors: Feder Toni
Published: May 2021

Moving forward requires research and international and intergenerational participation.
Improving management of sexually transmitted infections in primary care: feasibility and acceptability of a new patient management tool for clinicians
Authors: Rose Sally B. , Garrett Susan M. , Pullon Susan R. H.
Published: May 2021

ABSTRACT INTRODUCTION Routinely following an evidence-based clinical pathway of care for bacterial sexually transmitted infections (STIs) such as chlamydia or gonorrhoea is important to help reduce the spread of infections, prevent reinfections and avoid associated health complications. AIM To develop an easy-to-use tool for routine use by primary care clinicians to ensure best practice management of patients tested for and diagnosed with chlamydia or gonorrhoea. METHODS The tool (a MedTech Advanced Form) was developed in consultation with seven primary care clinicians and included different tabs for use during the STI care pathway (testing, treatment, advice, partner notification and follow up) with clickable links to relevant online resources. The tool was trialled over 3 months by 19 clinicians in three Wellington primary care clinics – two youth health and a student health service. Outcome measures were frequency of use, completeness of fields related to best practice care and clinician acceptance of the tool (from focus group feedback). RESULTS The tool was used for approximately one in four patients who were tested during the trial period, with ‘forgetting’ reported as the most common reason for non-use. Clinician views about the tool were favourable, with most indicating they would like to continue use and would recommend it to colleagues. Documentation of best practice care was excellent; fields to record reasons for testing, discussion of sexual history, provision of treatment and advice given were used for most patients for whom the form was completed. CONCLUSIONS Inclusion of this STI management tool in the electronic patient records system appeared to improve primary care clinicians’ delivery and documentation of best practice sexual health care at a practice level. Wider use of a modified version of this tool could facilitate more comprehensive best practice management of bacterial STIs.
The mRNA-destabilizing protein Tristetraprolin targets “meiosis arrester”
Nppc
mRNA in mammalian preovulatory follicles
Authors: Xi Guangyin , An Lei , Wang Wenjing , Hao Jing , Yang Qianying , Ma Lizhu , Lu Jinlun , Wang Yue , Wang Wenjuan , Zhao Wei , Liu Juan , Yang Mingyao , Wang Xiaodong , Zhang Zhenni , Zhang Chao , Chu Meiqiang , Yue Yuan , Yao Fusheng , Zhang Meijia , Tian Jianhui
Published: May 2021

Significance

The fertility of female mammals depends upon the well-orchestrated progression of oocyte meiosis, the female germ cell division that is essential for haploid oocyte formation. In preovulatory follicles, how LH induces a decrease in CNP and its encoding mRNA
Nppc
, a prerequisite for oocyte meiotic resumption, remains an outstanding question to understand the mechanism that controls oocyte meiosis. The present study shows that TTP, an mRNA-destabilizing protein, is one of the regulatory components responsible for the LH-induced rapid decrease in
Nppc
mRNA and oocyte meiotic resumption. This finding not only highlights the importance of posttranscriptional regulation in the follicle periphery to fine-tune oocyte meiosis but also provides an insight into CNP-dependent cGMP homeostasis in other physiological systems.
Storytelling increases oxytocin and positive emotions and decreases cortisol and pain in hospitalized children
Authors: Brockington Guilherme , Gomes Moreira Ana Paula , Buso Maria Stephani , Gomes da Silva Sérgio , Altszyler Edgar , Fischer Ronald , Moll Jorge
Published: May 2021

Significance

Storytelling is a unique human skill, yet we know little about its physiological and psychological impact. This study provides evidence of the biomarker changes and beneficial effects of storytelling in children admitted to an intensive care unit. We found that, compared with an active control condition, one storytelling session with hospitalized children leads to an increase in oxytocin, a reduction in cortisol and pain, and positive emotional shifts during a free-association task. These multimodal findings support evolutionary theories of storytelling and demonstrate its physiological and psychological effects under naturalistic stress conditions. These important clinical implications affirm storytelling as a low-cost and humanized intervention that can improve the well-being of hospitalized children.
The US Department of Justice stumbles on visual perception
Authors: Albright Thomas D.
Published: May 2021

A large and highly valuable category of forensic evidence consists of patterned impressions created during the perpetration of a crime. These crime scene artifacts, such as fingerprints or tire tracks, offer visual sensory information that is assessed by trained human observers and compared to sensory experiences elicited by model patterns that would have been produced under a hypothesized set of conditions. By means of this “forensic feature comparison,” the observer makes a judgment about whether the evidence and the model are sufficiently similar to support common origin. In light of documented failures of this approach, significant concerns have been raised about its scientific validity. In response to these concerns, the US Department of Justice has made assertions about how forensic examiners perform feature comparison tasks that are not consistent with modern scientific understanding of the processes of sensation and perception. Clarification of these processes highlights new ways of thinking about and improving the accuracy of forensic feature comparison and underscores the vital role of science in achieving justice.
Rhagoletis cingulata (cherry fruit fly).
Authors: Vogt Heidrun
Published: May 2021

R. cingulata (listed on EPPO A2 list) is a severe pest of cherries. It is closely connected to its host plants Prunus avium, P. cerasi, P. serotina, P. mahaleb and P. emarginata. Prunus mahaleb is native in warm locations of Southern and Central Europe. It is used as rootstock for tart cherries and as ornamental plant. In Germany R. cingulata appears 3-4 weeks later than the native species R. cerasi, and due to this attacks late cherry varieties, mainly tart cherries, e.g. the economic important variety "Schattenmorellen". This has been proven by fruit samples, from which pupae were obtained and in the following year R. cingulata adults emerged (species confirmed by Dr. Allen Norrbom, Systematic Entomology Laboratory, USDA). Infestation levels in tart cherries amounted to more than 20%.
The Rab7 effector WDR91 promotes autophagy-lysosome degradation in neurons by regulating lysosome fusion
Authors: Xing Ruxiao , Zhou Hejiang , Jian Youli , Li Lingling , Wang Min , Liu Nan , Yin Qiuyuan , Liang Ziqi , Guo Weixiang , Yang Chonglin
Published: May 2021

The effectors of the Rab7 small GTPase play multiple roles in Rab7-dependent endosome-lysosome and autophagy-lysosome pathways. However, it is largely unknown how distinct Rab7 effectors coordinate to maintain the homeostasis of late endosomes and lysosomes to ensure appropriate endolysosomal and autolysosomal degradation. Here we report that WDR91, a Rab7 effector required for early-to-late endosome conversion, is essential for lysosome function and homeostasis. Mice lacking Wdr91 specifically in the central nervous system exhibited behavioral defects and marked neuronal loss in the cerebral and cerebellar cortices. At the cellular level, WDR91 deficiency causes PtdIns3P-independent enlargement and dysfunction of lysosomes, leading to accumulation of autophagic cargoes in mouse neurons. WDR91 competes with the VPS41 subunit of the HOPS complex, another Rab7 effector, for binding to Rab7, thereby facilitating Rab7-dependent lysosome fusion in a controlled manner. WDR91 thus maintains an appropriate level of lysosome fusion to guard the normal function and survival of neurons.
Platelets instruct T reg cells and macrophages in the resolution of lung inflammation
Authors: Kapur Rick , Semple John W.
Published: May 2021

Platelets convey important nonhemostatic immune functions; however, their potential role in resolving pulmonary inflammation remains to be determined. In this issue of JEM, Rossaint et al. (2021. J. Exp. Med. https://doi.org/10.1084/jem.20201353) reveal that platelets contribute to the resolution of pulmonary inflammation by directly recruiting T regulatory (T reg) cells to the lungs and by transcriptionally reprogramming alveolar macrophages toward an anti-inflammatory phenotype.
Higher-Twist Effect in Pion Parton Distribution
Authors: Wan Lihong , Ruan Jianhong
Published: May 2021

A higher-twist modified parton evolution equation is used to evolve the initial valence quark distributions in pions, which are derived based on light-front quantization via BLFQ collaboration. The results are consistent with the valence quark distributions of the E615 experiment, and the pion structure function of the H1 experiment. The structure function data highlight the necessity for a higher-twist modification in the small x region. Comparisons with some other models are also given.
Photoelectron emission via time and phase-tailored electromagnetic fields
Authors: Wätzel Jonas , Hahn Johannes , Berakdar Jamal
Published: May 2021

The energy and the angular distributions of photoelectrons are shown to be tunable by choosing the time and the spatial phase structure of the driving fields. These conclusions are derived from quantum mechanical calculations done within a single-active electron model for an atomic target subjected to a combination of laser field and a time-asymmetric THz pulse and/or vortex-laser pulse with a spatially modulated phase of the wavefront.
Effects of the shape of curvature peaks on the size of primordial black holes
Authors: Escrivà Albert , Romano Antonio Enea
Published: May 2021

We simulate numerically the formation of spherically symmetric primordial black holes (PBHs) seeded by different families of primordial curvature perturbations profiles in a radiation dominated Friedman-Robertson-Walker (FRW) Universe. We have studied the dependency on the curvature profile of the initial mass M
BH,i of the PBHs at the time of apparent horizon formation t
AH, and the final mass M
BH,f after the accretion process, using an excision technique, comparing M
BH,i to previous analytical estimations obtained using a compensated PBHs model approach. The analytical estimations are in agreement with numerical results, except for large values of the initial perturbation amplitude, when the compensated model is less accurate. The masses M
BH,f and M
BH,i do not depend only on the shape around the compaction function peak, but on the full profile of the initial curvature perturbation. We also estimate the accretion effects, and for PBHs with masses relevant for the dark matter abundance, with a final mass equal to the horizon crossing mass, we find M
BH,f ≈ 3 M
BH,i.
Third-order nonlinear optical properties of graphene composites: A review*
Authors: Shang Meng , Li Pei-Ling , Wang Yu-Hua , Luo Jing-Wei
Published: May 2021

Graphene has excellent thirdorder nonlinear optical (NLO) properties due to its unique electronic band structure and wideband gap tunability. This paper focuses on the research progress of graphene and its composite materials in nonlinear optics in recent years. In this review, recent results on graphene (or graphene oxide)–metal nanoparticles (G-MNPs), graphene–metal–oxide nanoparticles (G-MONPs), graphene–metal sulfide nanoparticles (G-MSNPs), and graphene–organic molecular composites (G-OM) have been discussed. In addition, the enhancement mechanism of nonlinear absorption (NLA) and optical limiting (OL) have also been covered.
PDE-solved by boundary element method for electrical impedance tomography
Authors: Rymarczyk T , Polakowski K , Sikora J
Published: May 2021

In this article a new version of the algorithm for Electrical Impedance Tomography is presented. By describing the problem with differential equations brought to integral equations, the algorithm can be used for many types of tomography. The approach used is particularly useful where it is not possible to formulate boundary conditions at the outer boundary of the region. Influence of the proximity effect on precision of imaging was considered.
A structured light image quality evaluation method based on no-reference quality assessment
Authors: Ji W Z , Xue Q , Sun X H , Sun P P , Meng H
Published: May 2021

Affected by noise, color, and light blocking, there are some large error data contained in the results of structured light 3D measurement. In the absence of effective criterion, the data can only be recognized artificially. In this paper, a criterion based on Human Vision System (HVS), which can be applied to recognize the large error data by evaluating the noise variance level of the stripe images, and a method used to improve the level of measurement accuracy are proposed. According to the proposed method, the no-reference quality assessment is used to evaluate the quality of stripe images. With the noise evaluation coefficient, the large error data can be identified automatically. The experimental results show that this method is efficient in detecting large error data in the stripe images.
Three-dimensional reconstruction method based on jitter optimization
Authors: Liang Peichen , Zheng Weixin , Xu Xiao
Published: May 2021

For obtaining richer visual information and eliminating mismatched points faster, a jitter-optimized 3D reconstruction algorithm is proposed. First, we built a stereo vision system that can capture images from multiple views of a jittering plane mirror. A vector-based method is defined to evaluate the performance of 3D point cloud and predict the optimal jittering state of the object, and then select robust feature points with integration optimization strategy. Experimental results show that the proposed algorithm can efficiently eliminate mismatched points and supplement robust features. Furthermore, selecting a reasonable visual angle of the binocular cameras will significantly improve the effect of jitter optimization, and higher-quality reconstruction will be obtained. The proposed method can solve the difficult problem to change the pose of the object or adjust the position of the binocular cameras to capture images from multiple views.
Research Summary of Blockchain Fragmentation Propagation Mechanism Based on Merkel Tree
Authors: Liwei Tian , Yu Sun
Published: May 2021

At present, when the blockchain system propagates blocks, it is a point-to-point propagation of complete blocks. This method has three shortcomings: the propagation load is large; the message can only be received from one node; only after the complete block is received, can it be propagated to other nodes. Therefore, this article considers changing the block’s Merkel tree data structure to minimize the data size during block propagation while ensuring that the receiving node can reconstruct the correct and complete block. On the other hand, in order to be able to receive blocks from multiple nodes at the same time and relay to other nodes when incompletely received, the blocks are fragmented and then reorganized. At the same time, the correctness of a single fragment can also be verified.
Support grid integration of offshore wind power
Authors: Han Xingning , Zhao Feifei , Ma Jinlong , Ye Xueshun , Sun Yong
Published: May 2021

China has a cumulative installed offshore wind capacity of 6.8 GW, making it the third largest in the world. Compared with Europe, which is the largest offshore wind power market, there are still gaps to substantially tapping the offshore wind potentials of China. This paper aims to investigate advanced experience of offshore wind power, and explore innovative approaches for offshore wind deployment and grid integration in China. Development and issues caused by offshore wind power in UK, Germany and Denmark have been investigated, including technological progress, curtailment, and network congestion and redispatch needs. The grid integration approaches to re-enforcement of network to accommodate offshore wind power are also analysed. Contrastive analysis is taken about stakeholders and planning process of offshore wind among UK, Germany, and Denmark. Construction suggestions are proposed for the development of offshore wind power in China during the 14th Five Year Plan period.
Optimization Decision Method based on Nonlinear Analytic Hierarchy Process for Active Distribution Network Planning
Authors: Zheng Xuejun , Hu Xin , Li Jingsong , Li Yan , Luo Xiaotong , Wang Shaorong
Published: May 2021

Aiming at the investment environment of the distribution network, this paper deeply analyses the investment conditions of the distribution network, introduces the analytic hierarchy process and modern investment theory, establishes the analytic hierarchy of the investment conditions in the distribution network project, and proposes an optimization decision-making method of investment plan in distribution network. This paper also establishes two new concepts: condition score and correlation score, uses the improving analytic hierarchy process to calculate the weights, proposes a priority ranking method for distribution network projects, and gives detailed process. to formulate distribution network investment plans. The application of the proposed method to optimize the distribution network planning scheme shows that the optimization investment scheme given has better investment benefits under the condition of the power supply reliability requirements of the distribution network and investment capital constraints.
An integrated energy system scheduling optimization method considering economy, stability and environmental protection
Authors: Lou Qinghui , Chen Jun , Niu Honghai , Qiu Rui , Wu Jun , Gao Yuan , Ma Xiangzhui , Guan Xiaocheng , Ouyang Jun
Published: May 2021

In this paper, first, an energy efficiency evaluation method including economy, stability and environmental protection was given. Second, a mathematical model of the integrated energy system and a single-objective economic optimization model under different operation conditions, which add renewable energy and power storage equipment and could be solved based on the greedy algorithm, were given to improve the energy efficiency. Finally, an integrated energy system including wind power, photovoltaics, power storage equipment and conventional loads was taken as an example. Considering the time-of-use electricity price and the full utilization of energy storage, 4 optimization plans were set up for comprehensive energy efficiency evaluation and comparison. The result shows that the energy efficiency evaluation method proposed in this paper is practical and feasible, and the optimization method proposed plays a guiding role in the operation of similar parks.
Zinc and cerium synergistically enhance the mechanical properties, corrosion resistance, and osteogenic activity of magnesium as resorbable biomaterials
Authors: Behera Manisha , Rajput Monika , Acharya Srijan , Nadammal Naresh , Suwas Satyam , Chatterjee Kaushik
Published: May 2021

Magnesium and its alloys have the potential to serve as a revolutionary class of biodegradable materials, specifically in the field of degradable implants for orthopedics. However, the corrosion rate of commercially pure magnesium is high and does not match the rate of regeneration of bone tissues. In this work, magnesium alloys containing zinc and cerium, either alone or in combination, were investigated and compared with commercially-pure magnesium as biomaterials. The microstructure, mechanical properties, corrosion resistance, and response of osteoblasts in vitro were systematically assessed. Results reveal that alloying with Ce results in grain refinement and weakening of texture. The tensile test revealed that the ternary alloy offered the best combination of elastic modulus (41.1 ± 0.5 GPa), tensile strength (234.5 ± 4.5 MPa), and elongation to break (17.1 ± 0.4%). The ternary alloy was also the most resistant to corrosion (current of 0.85 ± 0.05 × 10−4 A cm−2) in simulated body fluid than the other alloys. The response of MC3T3-E1 cells in vitro revealed that the ternary alloy imparts minimal cytotoxicity. Interestingly, the ternary alloy was highly efficient in supporting osteogenic differentiation, as revealed by the expression of alkaline phosphatase and calcium deposition. In summary, the extruded Mg alloy containing both Zn and Ce exhibits a combination of mechanical properties, corrosion resistance, and cell response that is highly attractive for engineering biodegradable orthopedic implants.
Remote climate change propagation across the oceans—the directional swell signature
Authors: Lemos Gil , Semedo Alvaro , Hemer Mark , Menendez Melisa , Miranda Pedro M A
Published: May 2021

The energy content of wind-waves is propagated across the oceans in the form of swell waves, the main drivers of long-term changes in coastal morphology and offshore hazards. A state-of-the-art swell tracking algorithm is applied to a global ensemble of CMIP5 dynamic wave climate projections, to assess future changes in remotely originated swell events towards the end of the 21st century, and how they propagate. The contribution of multiple wave generation areas is considered. It is found that the projected climate change signal is effectively propagated from the winds along the extratropical storm tracks to remote locations, in the tropical and subtropical latitudes, through swell waves. The statistically significant projected changes in swell wave heights and swell predominance at the remote swell arrival locations are comparable with the ones at the wave generation areas. Furthermore, different incoming directions for swell events at remote locations are shown to often carry opposite climate change signals, propagated from different remote origins. These results highlight the need for a directional approach on wave climate projections, critical for improved vulnerability assessments and adaptation measures from the climate community.
Impact of commercial cellulase enzyme on the quality of Clinacanthus nutans extracts
Authors: Kasim K F , Husin N , Shamsudin S , Amer N A M , Salleh N H M , Sofian-Seng N S
Published: May 2021

The use of enzymes such as cellulase and pectinase to aid in the fruit and vegetable juice extraction is a common practice. However, this practice is very limited in the production of juice or extract from green leaves. This study was carried out to evaluate the impact of commercial cellulase enzyme on the volume yield recovery, total chlorophyll and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of the Clinacanthus nutans leaves and stem. Leaves extract showed higher volume yield recovery, total chlorophyll content and DPPH scavenging activities (0.72±0.02 mL, 50.10±3.96 mg/L and 70% respectively) compared to the stem extract (0.60 ± 0.1 mL, 39.70 ± 4.73 mg/L and 25% respectively). It was also found that the cellulase enzyme concentrations were proportional to the volume yield recovery, and DPPH scavenging activity of the C. nutans extract over time. However, there was no significant effect of enzyme concentration on the total chlorophyll content. The results obtained can be considered very satisfactory and cellulase enzyme can be considered to be used in the aqueous extraction of C. nutans to aid the extraction process in order to increase the volume yield recovery, total chlorophyll content and DPPH scavenging activities.
Evaluation of biodegradable activity of film from chicken feather keratin
Authors: Hasyierah M S Noor , Lim W J , Munirah R Noor , Rahayu M Alina , Zafifah Z , Farihan K Khairul
Published: May 2021

The disposal of plastic caused serious environmental pollution to both land and sea. Chicken feather wastes also contributed to pollution problem and its value has not been fully utilized. This study aimed to produce biodegradable film by utilizing keratin extracted from chicken feathers. Initially, the keratin was extracted from chicken feather prior to the optimization of the keratin biofilm towards the tensile strength. The involved parameters were ratio of keratin toglycerol, ratio of keratin to PVA and drying temperature. The biofilm was proceeded to morphological, chemical structure and colour characterization analysis using SEM, FTIR and chromameter, respectively. The keratin obtained was 0.1296mg/ml. The obtained keratin was then used in the formulation of biofilm. The biofilm with 40:50:10 (volume ratio of keratin: PVA:glycerol) dried at 60°C showed the optimum tensile strength. The FTIR showed the presence of amide and hydroxyl groups. From biodegradability test, it was proven that blend of keratin, PVA and glycerol films can be degraded by microorganisms in soil in which films with higher concentration of glycerol degrading faster compared to those with lesser glycerol concentration. Thus, it can be concluded that the chicken feather keratin offers an alternative as biofilm for biodegradable plastic.
Identification of chemical compounds from agarwood hydrosol (Aquilaria malaccensis) fruits via LC-QTOF-MS/MS analysis
Authors: Azhar M A , Rahman N W A , Aziz M A A , Isa K M
Published: May 2021

Gaharu hydrosol is being considered as a by-product produced during the hydrodistillation of resinous wood part of Aquilaria spp. Agarwood hydrosol was reported to possess many bioactive compounds that are beneficial for health. However, current studies on the chemical composition of agarwood hydrosol from the fruit part are still lacking. This research presents the untargeted chemical compound of agarwood hydrosol from Aquilaria malaccensis fruit (AF) via liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS/MS) and comparison the active functional groups with industrial hydrosol grade using Fourier transform infrared (FTIR). Qualitative tandem LC-QTOF-MS/MS was utilised to identify compounds in the extracted sample. The data processing revealed the presence of 128 known compounds in the hydrosol from A. malaccensis fruit in negative ionization mode and only one chemical profile detected after switched to positive ionization mode. This result contains the retention times value of m/z [M - H-], [M + HCOO-], [M + H+] and similar database search hit identities of the 129 compounds detected during the LC-QTOFMS/MS analysis in Table A1 and A2.
Biotic Degradation of Plastic Hygiene Products by Using Pleurotus ostreatus
Authors: Mismisuraya M A , Yaacob Noorulnajwa Diyana , Zulkifle Nor Ain Najihah
Published: May 2021

Degradation is any physical or chemical adjustment in polymer due to environment factor, such as heat, moisture, light, chemical conditions and biological activity. The aim of this work was to determine the biotic degradation efficiency of plastic hygiene products by using Pleurotus ostreatus. Sanitary pads and diapers were used as samples. All the samples will be exposed to the Pleurotus ostreatus for 90 days. The degradation efficiencies were analysed based on tensile reduction, morphology and chemical properties of the samples by using universal tensile machine, Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), respectively. The tensile reduction percentage for all samples was increase. The morphology and chemical properties of the samples also showed some changes after undergoes 90 days degradation.
Utilizing Lignosulfonate from Coconut Husk as Sacrificial Agent to Reduce Surfactant Adsorption
Authors: Daud N M A N , Jaafar W M K W , Ismail N , Junin R , Manan M A. , Idris A K
Published: May 2021

The adsorption of surfactants from aqueous solutions in porous media is essential in enhanced oil recovery (EOR) from oil reservoirs. Surfactant loss that is due to adsorption by the reservoir rocks weakens the efficiency of the chemical slurry that is injected and decreases the oil-water interfacial tension (IFT). One of the ways to reduce the reduction is by using a sacrificial agent. This project will focus on utilizing the lignosulfonate (LS) from coconut husk as a sacrificial agent to reduce the surfactant adsorption. Lignin was extracted from coconut husk before sulfonated using sodium sulphite, Na 2SO 3 to form lignosulfonate. Fourier transform infrared (FTIR) spectroscopy was used to characterize the lignin and lignosulfonate and compare them with the commercial product. The batch experiment then conducted using a clay mineral of illite as the adsorbent. Two types of surfactants were studied; anionic (Sodium Dodecyl Sulfate-SDS) and non-ionic (4-octylphenol polyethoxylate-TX100). The amount of adsorbed surfactant was determined by measuring the surfactant critical micelle concentration (CMC) before and after the adsorption tests. The result in the batch experiment shows that LS reduced the surfactant adsorption on illite by about 54.2% for SDS and 42.6% for TX100. This showed that lignosulfonate has the potential as a sacrificial agent to minimize the surfactant adsorption, and agriculture waste like coconut husk can be utilized for this purpose.
Adsorption of carbon dioxide (CO 2) by activated carbon derived from waste coffee grounds
Authors: Lim H K , Ali U F Md , Ahmad R , Aroua M K
Published: May 2021

Currently, three are several agricultural bio-based materials have been successfully utilized as gas adsorbents. In this study, waste coffee grounds (WCGs) have been selected as a potential precursor of Carbon Dioxide (CO 2) adsorbents. The preparation parameters for activated carbon derived from WCGs were optimized using Response Surface Methodology (RSM). The optimized preparation parameters were found to be 1:3.67 impregnation ratio of acid, 533°C of carbonization temperature and 1.13 hours of activation time, which resulted in 23.6 wt% of yield. The physical and chemical characteristics of WCGAC in terms of surface morphology, carbon content, ash content and yield were also investigated. The CO 2 breakthrough time using WCGAC were carried out at the temperatures of 30, 40, and 60°C. It was found that WCGAC shows a longer CO 2 breakthrough times (5 mins) and a higher adsorption capacity (4.33 mg CO2/g adsorbent) at 30°C.
Anaerobic co-digestion of chicken manure with energy crop residues for biogas production
Authors: Dawi Cahyono N.A , Shamsuddin M.R. , Ayoub M. , Mansor N. , Isa N.H.M. , Nagoor Gunny A.A
Published: May 2021

Biogas or bio-methane is an alternative energy source produced by anaerobic digestion (AD) technology whereby the organic matter is degraded by naturally present microorganisms and converted into a combustible gas. This paper focus on the utilization of anaerobic codigestion (AcoD) method since biogas yield so far remains minimum based on mono-digestion alone due to low energy content. In this work, empty fruit bunch (EFB), oil palm frond (OPF) and sugarcane bagasse (SB) are being used as co-digestion additive since energy crop residues are known for its high carbon and energy content to enhance the process. A series of five 1.5L reactors were set up for a mesophilic condition at temperature 40°C, with initial pH range of 7-8, for 60 days of retention time. The mono-digestion reactor of chicken manure is labelled as DC1, and the co-digestion reactors with sugarcane bagasse, OPF and EFB are labelled as DSB, DOPF and DEFB, respectively. The recorded C/N ratio of co-digestion reactors were improved to be in a favourable range of 15 to 35 with DSB being the highest at 17.74 compared to that of control reactor at 11.35. As a result, total biogas production for DSB increases up to 36% due to its significantly high carbon content from sugarcane bagasse that provide stability for the bacterial growth and its activities. Sugarcane bagasse act as a good carbon source for the AD system, thus enhance the methane production. On the other hand, DOPF and DEFB give 13% and 41% lesser total biogas volume, however, produces much higher methane concentration compared to the control reactor. This shows that DOPF and DEFB give a higher methane yield which defines the more stability and efficiency of digestion process.
Amine Functionalized Carbon-based Soybean Curd Residues (SCR) as Potential Adsorbent for Carbon Dioxide Adsorption
Authors: Zakaria D S , Rozi S K Mahmad , Halim H N Abdul , Mohamad S
Published: May 2021

Currently, carbon dioxide (CO 2) capture can preserve environmental quality by using carbon-based adsorbent. In this research, Polyethylenehexamine (PEHA) functionalized carbon-based soybean curd residues (carbonized SCR-PEHA) was prepared for CO 2 adsorption. Analysis of functional groups of the prepared adsorbent using Fourier Transform Infrared Spectroscopy (FTIR), confirmed the functionalization of PEHA on the carbonized SCR. CO 2 uptake of the carbonized SCR-PEHA was compared with the bare SCR using Thermogravimetric Analyzer (TGA) analysis. TGA results revealed that the adsorption capacity of CO 2 for carbonized SCR-PEHA and bare SCR are 8.816 mg/g and 3.027 mg/g respectively. It was observed that functionalization of the PEHA on the surface of carbonized SCR had improved the adsorption capacity of CO 2 by 2.92 times as compared to bare SCR. The phenomenon can be explained from the interaction of the CO 2 with the available amine sites provided for the carbonized SCR-PEHA which significantly improved the CO 2 adsorption. Hence, the carbonized SCR-PEHA demonstrate potential adsorbent for CO 2.
Effect of different growing media and media water status on leaf biomass of Andrographis paniculata
Authors: Isa M M , Kasim K F , Muttalib M F A , Jaafar M N
Published: May 2021

Andrographis paniculata is a medicinal plant that widely distributed in a variety of habitats throughout the world. It has a wide range of medicinal and pharmacological application. This study is aims to investigate the effect of different growing media and media water status on the leaf biomass of A. paniculata. An experiment was conducted at the greenhouse Institute of Sustainable Agrotechnology (INSAT), Universiti Malaysia Perlis (UniMAP). The experiment was laid out in randomized complete block design (RCBD) of two factors consisting of 9 treatments with 3 replications. Three different growing media were applied, namely compost, topsoil and sand. The growing media were combined in different ratios (1:2:3, 2:2:1 and 3:2:1) with three different soil water potential; -20 kPa (high), -60 kPa (medium) and -100 kPa (low). The crops were harvested 115 Days after transplanting at maturity. There were significant increases on leaves biomass in each plant that had been planted in media mixture contained compost: topsoil: sand (3:2:1) under high soil water potential compared to other treatments. Besides, there were significant interaction effects between growing media and soil water potential were observed for this plant part. The study concluded that the application of potting mixture that contained compost, topsoil and sand in a ratio 3:2:1 with well water supplied are recommended for A. paniculata grown under greenhouse condition.
Isothermal torrefaction of coconut fiber in a fixed bed reactor
Authors: Mohamed Alina Rahayu , Fu Nur Izzati Ismail , Salleh Noor Hasyierah Mohd , Ahmad Razi , ismaii Ras Izzati
Published: May 2021

Torrefaction of coconut fiber was performed in a fixed bed reactor at torrefaction temperature of 220-300°C and holding time of 20-60 mins under nitrogen atmosphere. The torrefaction reaction kinetics were determined using the Coats-Redfern method. The values of activation energy and pre-exponential factor at holding time of 20, 40 and 60 minutes are in the range of 30.25-43.61 kJ/mol and 4.03-152.69 min -1 respectively. The proximate analysis was performed on the raw and torrefied coconut fiber. It was identified that the moisture content and volatile matter decreased but the ash content and the fixed carbon increased when the torrefaction temperature were increased from 220-300 °C. The morphological properties of coconut fiber and torrefied coconut fiber were analyzed using Scanning electron microscope (SEM). From SEM, the degree of severity due to torrefaction process towards the surface structure of torrefied coconut fiber can be visualized and increased with increasing torrefaction temperature with merging of pores. The existence of functional group such as hydroxyl (O-H) and alkane (C-H) were identified on the surface of raw and torrefied coconut fiber by Fourier Transform Infrared spectroscopy (FTIR).
Dual grinding and mixing machine for vermicompost and worm biomass production
Authors: Atienza A H , Erinco I K , Martinez M B , Visande V J
Published: May 2021

Agricultural wastes come from different farming and planting activities that can be used as main material for organic fertilizers and compost. To improve the quality of the compost, it is better to include earthworms in the mixture to become vermicompost. Vermicompost is made up of enriched fertilizer with the production of earthworm known as worm biomass. The preparation of the vermicompost consists of grinding the waste in tiny bits and mixing manually which consumes a lot time and effort. This study focuses on the design of a dual grinding mixing machine intended for vermicompost and worm biomass production. The earthworm used in this study is African Night Crawler species. There are 13 testing vermicompost beds used for the experiment. The machine reduced the preparation time to one-third compared to manual operation. There is increase in the production of vermicompost by 87.5 kg and worm biomass by 3.5 kg, respectively, in monthly basis.
A Single Step Transesterification Process to Produce Biodiesel from The Spent Cooking Oil
Authors: Herman Indah Thuraya , Isa Khairuddin Md , Ibrahim Naimah , Kasim Farizul Hafiz , Aziz Mohd Aizudin Abd
Published: May 2021

A direct process of transesterification has been carried out to produce high yields of biodiesel. Conversion of waste cooking oil to methyl esters was performed using potassium hydroxide-glycerol (KOH-Gly) as a catalyst. KOH-Gly was produced by mixing KOH and glycerol at a mass ratio of 1:20 at a temperature of 80 °C for 120 minutes. The process of transesterification was performed at a reaction temperature of 60 °C, a molar ratio of oil to methanol of 1:6, 2% wt KOH-Gly catalytic loading for 30 minutes. This process resulted in a waste cooking oil conversion yield of about 97-98% to biodiesel using KOH-Gly as a catalyst. The two layers of the product were produced without the formation of soap, which facilitated the separation and purification process. Gas chromatography-mass spectrometry was used to analyse the chemical content of biodiesel.