bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of human white matter pathways in utero over the second and third trimester
Authors: Wilson Siân , Pietsch Maximilian , Cordero-Grande Lucilio , Price Anthony N. , Hutter Jana , Xiao Jiaxin , McCabe Laura , Rutherford Mary A. , Hughes Emer J. , Counsell Serena J. , Tournier Jacques-Donald , Arichi Tomoki , Hajnal Joseph V. , Edwards A. David , Christiaens Daan , O’Muircheartaigh Jonathan
Published: May 2021

Significance

This work uses state-of-the-art acquisition and analysis methods developed specifically for fetal MRI to delineate the developing brain’s association, projection, and callosal white matter pathways. We describe unique, heterogenous maturational trajectories for different tracts, suggesting that regionally distinct biological mechanisms are at play in building the structural connectome in utero.
Risk of groundwater contamination widely underestimated because of fast flow into aquifers
Authors: Hartmann Andreas , Jasechko Scott , Gleeson Tom , Wada Yoshihide , Andreo Bartolomé , Barberá Juan Antonio , Brielmann Heike , Bouchaou Lhoussaine , Charlier Jean-Baptiste , Darling W. George , Filippini Maria , Garvelmann Jakob , Goldscheider Nico , Kralik Martin , Kunstmann Harald , Ladouche Bernard , Lange Jens , Lucianetti Giorgia , Martín José Francisco , Mudarra Matías , Sánchez Damián , Stumpp Christine , Zagana Eleni , Wagener Thorsten
Published: May 2021

Significance

Clean groundwater is essential for water supply in many regions of the world. Fast flow to the groundwater through enlarged cracks and fissures, which is known to transmit short-lived pollutants into the groundwater, is often neglected in large-scale studies. We quantify the rapid transport of pollutants by fast flow into the carbonate rock groundwater storage in Europe, North Africa, and the Middle East. We show that, through rapid transport, up to 50% of infiltrating pollutants may still reach the groundwater table, which is substantially more than estimated when fast transport is neglected. These results imply that the contamination risk of usable groundwater storages is much larger than expected where fast flow to the groundwater occurs.
Widespread deep seismicity in the Delaware Basin, Texas, is mainly driven by shallow wastewater injection
Authors: Zhai Guang , Shirzaei Manoochehr , Manga Michael
Published: May 2021

Significance

The Delaware Basin, western Texas, has experienced a surge in the number of earthquakes. We investigate basin-wide earthquake, hydrogeologic, industrial, and geodetic data spanning 1993–2020 to identify the reasons for the increase. We use these data and models to quantify the stress changes from wastewater injection and hydrocarbon extraction. We demonstrate that the basin-wide seismicity is dominated by the stresses caused by shallow injection that are transmitted vertically by deforming the underlying crust. We analyze both injection and production data to understand how subsurface properties control earthquake locations and timings. We suggest that injecting wastewater into porous formations will minimize seismic hazard. We establish a framework explaining why earthquakes sometimes occur and sometimes do not occur within human activity-impacted areas.
Uncovering a novel role of PLCβ4 in selectively mediating TCR signaling in CD8+ but not CD4+ T cells
Authors: Sasai Miwa , Ma Ji Su , Okamoto Masaaki , Nishino Kohei , Nagaoka Hikaru , Takashima Eizo , Pradipta Ariel , Lee Youngae , Kosako Hidetaka , Suh Pann-Ghill , Yamamoto Masahiro
Published: May 2021

Because of their common signaling molecules, the main T cell receptor (TCR) signaling cascades in CD4+ and CD8+ T cells are considered qualitatively identical. Herein, we show that TCR signaling in CD8+ T cells is qualitatively different from that in CD4+ T cells, since CD8α ignites another cardinal signaling cascade involving phospholipase C β4 (PLCβ4). TCR-mediated responses were severely impaired in PLCβ4-deficient CD8+ T cells, whereas those in CD4+ T cells were intact. PLCβ4-deficient CD8+ T cells showed perturbed activation of peripheral TCR signaling pathways downstream of IP3 generation. Binding of PLCβ4 to the cytoplasmic tail of CD8α was important for CD8+ T cell activation. Furthermore, GNAQ interacted with PLCβ4, mediated double phosphorylation on threonine 886 and serine 890 positions of PLCβ4, and activated CD8+ T cells in a PLCβ4-dependent fashion. PLCβ4-deficient mice exhibited defective antiparasitic host defense and antitumor immune responses. Altogether, PLCβ4 differentiates TCR signaling in CD4+ and CD8+ T cells and selectively promotes CD8+ T cell–dependent adaptive immunity.
A fast image reconstruction method for planar objects CT inspired by differentiation property of Fourier transform (DPFT)
Authors: Zhao Shusen , Xia Dimeng , Zhao Xing
Published: May 2021

In planar objects computed tomography (CT), restricted to the scanning environment, projections can only be collected from limited angles. Moreover, limited by the emitting power of the x-ray source, only a few photons penetrate the long side of the planar objects, which results in the noise increasing in projections. Planar objects CT reconstruction based on these two conditions is mathematically corresponding to solving an ill-posed inverse problem. Although several iterative reconstruction algorithms of limited-angle CT were proposed, high-quality planar objects CT reconstruction algorithms with fast convergence are still the goals of many researchers. In order to address the aforementioned problems, we proposed a new optimization model for planar objects CT reconstruction. Inspired by the theory of ‘visible boundary and invisible boundary’ in limited-angle CT and the differentiation property of Fourier transform, a new optimization objective function is proposed in this paper. Based on the statistical noise model of existing CT system, the convex set constraint of the optimization model is given. Besides, the optimization model is solved by convex set projection and Fourier transform differentiation property. The proposed algorithm was evaluated with both simulated data and real data. The experimental results show that the proposed algorithm can achieve the effect of noise suppression, limited-angle artifacts reduction, and fast structure reconstruction when it applies to planar objects CT.
Enhanced performance of ultra-thin polyaniline supercapacitor via aniline blue-WS SAMs with rich nucleation site
Authors: Kiymaz Deniz , Kiymaz Aykut , Dincalp Haluk , Zafer Ceylan
Published: May 2021

We report the ultrathin supercapacitor’s superior performance via the vertically aligned one-dimensional polyaniline structure (1D PANI) growth on the fluorine-doped tin oxide (FTO) substrate. FTO electrodes were treated by the molecular-self assembly, and the effects of different self assembled monolayers (SAMs) on both the evolution of PANI and electrochemical performance were examined. We obtained 809.09 F g−1 specific capacitance from ∼120 nm thick PANI (at 20 mV s−1 scan rate of cyclic voltammetry) via aniline blue water soluble SAMs modification. The supercapacitor’s internal dynamics were clarified by a new equivalent circuit model developed from the Graham model. Through the new model, accurate information about double-layer capacitance, percolation capacitance, and bulk capacitance, which composes the electrode’s capacitive performance, could be obtained. This work provided novel knowledge to develop PANI deposition and hence to achieve greater capacitances.
Low-energy in-gap states of vortices in superconductor–semiconductor heterostructures
Authors: Ziesen Alexander , Hassler Fabian
Published: May 2021

The recent interest in the low-energy states in vortices of semiconductor–superconductor heterostructures are mainly fuelled by the prospects of using Majorana zero modes for quantum computation. The knowledge of low-lying states in the vortex core is essential as they pose a limitation on the topological computation with these states. Recently, the low-energy spectra of clean heterostructures, for superconducting-pairing profiles that vary slowly on the scale of the Fermi wavelength of the semiconductor, have been analytically calculated. In this work, we formulate an alternative method based on perturbation theory to obtain concise analytical formulas to predict the low-energy states including explicit magnetic-field and gap profiles. We provide results for both a topological insulator (with a linear spectrum) as well as for a conventional electron gas (with a quadratic spectrum). We discuss the spectra for a wide range of parameters, including both the size of the vortex and the chemical potential of the semiconductor, and thereby provide a tool to guide future experimental efforts. We compare these findings to numerical results.
Construction of 2D layered TiO2@MoS2 heterostructure for efficient adsorption and photodegradation of organic dyes
Authors: Omar Asmaa M A , Hassen Arafa , Metwalli Ossama I , Saber Mohamed R , Mohamed Sayed R E , Khalil Ahmed S G
Published: May 2021

In this work, heterostructures of coupled TiO2@MoS2 with different phases of MoS2 were synthesized via hydrothermal technique. The prepared materials were thoroughly characterized using various techniques, including XRD, SEM, transmission electron microscopy, Brunauer–Emmet–Teller, XPS, Zeta potential and UV–vis spectroscopy. The optimized nanocomposites were tested for the photocatalytic degradation of methyl Orange (MO) under visible light as well as the adsorption of Rhodamine b (RhB) and methelene blue (MB) dyes. The TiO2@1T/2H-MoS2 heterostructures exhibited a narrow bandgap compared to the other studied nanomaterials. A remarkable photodegradation efficiency of TiO2@1T/2H-MoS2 was observed, which completely degraded 20 ppm of MO after 60 min with high stability over four successive cycles. This can be assigned to the formation of unique heterostructures with aligned energy bands between MoS2 nanosheets and TiO2 nanobelts. The formation of these novel interfaces promoted the electron transfer and increased the separation efficiency of carriers, resulting in high photocatalytic degradation. Furthermore, the adsorption efficiency of TiO2@1T/2H-MoS2 was unique, 20 ppm solutions of RhB and MB were removed after 1 and 2 min, respectively. The superior adsorption performance of the TiO2@1T/2H-MoS2 can be attributed to its high surface area (279.9 m2 g−1) and the rich concentration of active sites. The kinetics and the isothermal analysis revealed that the TiO2@1T/2H MoS2 heterstructures have maximum adsorption capacity of 1200 and 970 mg g−1 for RhB and MB, respectively. This study provides a powerful way for designing an effective photocatalyst and adsorbent TiO2-based nanocomposites for water remediation.
A CFRP/PZT laminated piezoelectric motor with high force density
Authors: Cao Teng , Li Xiaoniu , Wen Zhiyi , Wang Boquan , Liu Wei , Yu De , Wu Dawei
Published: May 2021

This work presents a laminated piezoelectric (PZT) motor to achieve high force density, high strength, and compact structure. The oscillator consists of vibration units and a driving foot. Each of the vibration units is formed by symmetrically bonding two PZT ceramics on a carbon fiber-reinforced plastic (CFRP) layer to improve its strength. The oscillator works in hybrid mode of the first longitudinal vibration (L1) and second bending vibration (B2). The finite-element method is adopted to tune the resonance frequencies of the two modes, and the vibration characteristics are experimentally analyzed. The strength test shows that the presence of the CFRP layer can increase the overall strength of the oscillator by 28% compared with a pure PZT motor. To evaluate the performance, the load characteristics of the fabricated prototype (with a size of 39 × 10 × 4.6 mm3 and weight of 10.6 g) are tested on a designed testbed. The single-phase driving method is used to drive the motor, and the best performance is obtained at the B2-mode frequency. The maximum thrust force, no-load speed, and output power reach 17 N, 335 mm s−1, and 775 mW, respectively, at a drive voltage of 100 Vp. Meanwhile, a thrust density of 1604 N kg−1 and an output power density of 73.11 W kg−1 are achieved. The thrust density is much higher than that of the other motors that operate in the same modes.
Structure and frustrated magnetism of the two-dimensional triangular lattice antiferromagnet Na2BaNi(PO4)2
*
Authors: Ding Fei , Ma Yongxiang , Gong Xiangnan , Hu Die , Zhao Jun , Li Lingli , Zheng Hui , Zhang Yao , Yu Yongjiang , Zhang Lichun , Zhao Fengzhou , Pan Bingying
Published: May 2021

A new frustrated triangular lattice antiferromagnet Na2BaNi(PO4)2 was synthesized by high temperature flux method. The two-dimensional triangular lattice is formed by the Ni2+ ions with S = 1. Its magnetism is highly anisotropic with the Weiss constants θ
CW = –6.615 K (H ⊥ c) and –43.979 K (H ∥ c). However, no magnetic ordering is present down to 0.3 K, reflecting strong geometric spin frustration. Our heat capacity measurements show substantial residual magnetic entropy existing below 0.3 K at zero field, implying the presence of low energy spin excitations. These results indicate that Na2BaNi(PO4)2 is a potential spin liquid candidate with spin-1.
Effect of the potential function and strain rate on mechanical behavior of the single crystal Ni-based alloys: A molecular dynamics study*
Authors: Yin Qian , Lian Ye-Da , Wu Rong-Hai , Gao Li-Qiang , Chen Shu-Qun , Wen Zhi-Xun
Published: May 2021

Molecular dynamics has been widely used to study the fundamental mechanism of Ni-based superalloys. However, the effect of the potential function and strain rate on mechanical behavior has rarely been mentioned in the previous molecular dynamics studies. In the present work, we show that the potential function of molecular dynamics can dramatically influence the simulation results of single crystal Ni-based superalloys. The microstructure and mechanical behavior of single crystal Ni-based superalloys under four commonly used potential functions are systematically compared. A most suitable potential function for the mechanical deformation is critically selected, and based on it, the role of strain rate on the mechanical deformation is investigated.
Retrieval of the effective constitutive parameters from metamaterial absorbers*
Authors: Shi Shaomei , Qiao Xiaojing , Liu Shuo , Liu Weinan
Published: May 2021

The equivalent medium theory of metamaterials provides a way to obtain their effective constitutive parameters. However, because of its non-reciprocity, the complexity of the electromagnetic coupling, and a metallic bottom layer, it has been challenging to retrieve them from a metamaterial absorber. In this paper, we propose a method without any approximation to obtain them, in which the non-reciprocity and the strong electromagnetic coupling are included. Compared with the three methods such as symmetric metamaterial method, asymmetric metamaterial method and metasurface method, our method can reveal the metamaterial absorber’s electrical and magnetic resonance and show its electromagnetic coupling coefficients. To deal with a metamaterial absorber with a metallic bottom layer, four corners of the metallic bottom layer in the unit cell are removed, making it possible to retrieve the electromagnetic parameters. Surprisingly, these results show that the metamaterial absorber with a metallic bottom layer in our example operates in a negative refraction state at the half absorption frequencies, which helps further understand the absorbing mechanism of these metamaterial absorbers.
Nonlocal advantage of quantum coherence and entanglement of two spins under intrinsic decoherence*
Authors: Li Bao-Min , Hu Ming-Liang , Fan Heng
Published: May 2021

We investigate the nonlocal advantage of quantum coherence (NAQC) and entanglement for two spins coupled via the Heisenberg interaction and under the intrinsic decoherence. Solutions of this decoherence model for the initial spin-1/2 and spin-1 maximally entangled states are obtained, based on which we calculate the NAQC and entanglement. In the weak region of magnetic field, the NAQC behaves as a damped oscillation with the time evolves, while the entanglement decays exponentially (behaves as a damped oscillation) for the spin-1/2 (spin-1) case. Moreover, the decay of both the NAQC and entanglement can be suppressed significantly by tuning the magnetic field and anisotropy of the spin interaction to some decoherence-rate-determined optimal values.
Broad-band phase retrieval method for transient radial shearing interference using chirp Z transform technique*
Authors: Xue Fang , Duan Ya-Xuan , Chen Xiao-Yi , Li Ming , Yuan Suo-Chao , Da Zheng-Shang
Published: May 2021

The transient radial shearing interferometry technique based on fast Fourier transform (FFT) provides a means for the measurement of the wavefront phase of transient light field. However, which factors affect the spatial bandwidth of the wavefront phase measurement of this technology and how to achieve high-precision measurement of the broad-band transient wavefront phase are problems that need to be studied further. To this end, a theoretical model of phase-retrieved bandwidth of radial shearing interferometry is established in this paper. The influence of the spatial carrier frequency and the calculation window on phase-retrieved bandwidth is analyzed, and the optimal carrier frequency and calculation window are obtained. On this basis, a broad-band transient radial shearing interference phase-retrieval method based on chirp Z transform (CZT) is proposed, and the corresponding algorithm is given. Through theoretical simulation, a known phase is used to generate the interferogram and it is retrieved by the traditional method and the proposed method respectively. The residual wavefront RMS of the traditional method is 0.146λ, and it is 0.037λ for the proposed method, which manifests an improvement of accuracy by an order of magnitude. At the same time, different levels of signal-to-noise ratios (SNRs) from 50 dB to 10 dB of the interferogram are simulated, and the RMS of the residual wavefront is from 0.040λ to 0.066λ. In terms of experiments, an experimental verification device based on a phase-only spatial light modulator is built, and the known phase on the modulator is retrieved from the actual interferogram. The RMS of the residual wavefront retrieved through FFT is 0.112λ, and it decreases to 0.035λ through CZT. The experimental results verify the effectiveness of the method proposed in this paper. Furthermore, the method can be used in other types of spatial carrier frequency interference, such as lateral shearing interference, rotational shearing interference, flipping shearing interference, and four-wave shearing interference.
Signatures of strong interlayer coupling in γ-InSe revealed by local differential conductivity*
Authors: Fu Xiaoshuai , Liu Li , Zhang Li , Wu Qilong , Xia Yu , Zhang Lijie , Tian Yuan , Yin Long-Jing , Qin Zhihui
Published: May 2021

Interlayer coupling in layered semiconductors can significantly affect their optoelectronic properties. However, understanding the mechanisms behind the interlayer coupling at the atomic level is not straightforward. Here, we study modulations of the electronic structure induced by the interlayer coupling in the γ-phase of indium selenide (γ-InSe) using scanning probe techniques. We observe a strong dependence of the energy gap on the sample thickness and a small effective mass along the stacking direction, which are attributed to strong interlayer coupling. In addition, the moiré patterns observed in γ-InSe display a small band-gap variation and nearly constant local differential conductivity along the patterns. This suggests that modulation of the electronic structure induced by the moiré potential is smeared out, indicating the presence of a significant interlayer coupling. Our theoretical calculations confirm that the interlayer coupling in γ-InSe is not only of the van der Waals origin, but also exhibits some degree of hybridization between the layers. Strong interlayer coupling might play an important role in the performance of γ-InSe-based devices.
Merging and splitting dynamics between two bright solitons in dipolar Bose–Einstein condensates*
Authors: Li Xin , Gao Peng , Yang Zhan-Ying , Yang Wen-Li
Published: May 2021

We numerically study the interaction dynamics of two bright solitons with zero initial velocities in the one-dimensional dipolar Bose–Einstein condensates. Under different dipolar strengths, the two bright solitons can merge into a breathing wave, and then split or propagate constantly after several oscillating periods. We quantitatively study the breathing frequency of wave after merging and the asymmetry property of solitons after splitting,and analyze their formation mechanism by the system’s energy evolution. Also, the change of initial phase difference brings distinct effects on the soliton interaction. Our results provide insight into the new dynamical phenomena in dipolar systems and enrich the understanding for interaction between dipolar solitons.
Forests moderate the effectiveness of water treatment at reducing childhood diarrhea
Authors: Rasolofoson Ranaivo A , Ricketts Taylor H , Johnson Kiersten B , Jacob Anila , Fisher Brendan
Published: May 2021

Environmental degradation has been associated with increased burden of diseases such as malaria, diarrhea, and malnutrition. As a result, some have argued that continuing ecosystem change could undermine successes in global health investments. Here we conduct an empirical study to investigate this concern. Child deaths due to diarrhea have more than halved since the year 2000, partly due to increased access to improved water, sanitation and hygiene (WASH). We examine how the effectiveness of a water quality treatment may vary as a function of upstream watershed condition. We use data on occurrence of diarrhea and point-of-use water treatment methods from the Demographic and Health Surveys for Haiti and Honduras. We integrate these data with a variable that reflects the influence of upstream tree cover on surface water quality. Point-of-use chlorination is significantly associated with 3.4 percentage points reduction in prevalence of diarrheal disease on average. However, we only detect a significant reduction in diarrheal prevalence when upstream watersheds are moderately forested. At low upstream tree coverage, point-of-use water chlorination does not have significant effects, suggesting that forest clearing could undermine its effectiveness at reducing childhood diarrhea. Our results suggest that forested watersheds may reduce water-borne sediments and contaminants, and thus improve raw water quality in ways that moderate the effectiveness of water quality treatment. Watershed protection should be considered in WASH investments, as deforested watersheds could undermine their effectiveness, particularly in parts of low-income countries where access to improved WASH services is challenging.
Potential of ginger (Zingiber officinale) crude extract as a chemotherapeutic agent for tiger grouper (Epinephelus foscoguttatus) infected by Aeromonas hydrophila
Authors: Anjur N , Sabran S F
Published: May 2021

One week of study was conducted to observe the potential of ginger crude extract in the treatment of tiger grouper (Epinephelus foscoguttatus) infected by a pathogenic bacterium in aquaculture, Aeromonas hydrophila. A total of 135 fish were injected intraperitoneally with 0.1ml of A. hydrophila (106 CFU ml−1) and stock in 15 aquaria (13L). Four concentrations of ginger extract (0.4g/L, 0.8g/L, 1.2g/L and 2.0g/L) were used as the treatment and the control is 0g/L. Water parameters such as dissolved oxygen, pH, temperature and salinity of the treatment tank were in the range of (4.05 – 4.20 ppm), (7.2 – 8.2), (25.6 – 28.8°C) and (22-25ppt) respectively. The extract’s potential as a treatment agent in the infected fish was recorded in terms of fish survival and physical condition such as the sign of bacterial infection and swimming behaviour. The results show infected tiger grouper treated with a concentration of ginger extract of 0.8g/L can improve the survival rate of fish by 89%. It can be concluded that crude ginger extract can enhance the survival rate and has the potential to be used as a chemotherapeutic agent in bacterial infection of tiger grouper fish.
Two New Distributional Records of Gliding Squirrels in Merapoh Forest Complex, Pahang
Authors: Arifuddin M N , S Ostermann , H Yazid , I Normazzaliana , N J Amira , I Mukri , R Elly , C L Marieanne , S Appalasamy , V K Jayaraj
Published: May 2021

A preliminary survey on the diversity of gliding squirrels was conducted from September 2019 until February 2020 in several locations within Merapoh, Pahang, Peninsular Malaysia using standard line transect method. The survey areas include a pristine forest, logged-over forest and agro-forested plantations. Gliding squirrels were spotted using a headlamp, binoculars (8x30 magnification) and a Digital SLR affixed with a telephoto lens (Nikon D500 + Nikkor 200-500 F5.6 VR) as they are mainly nocturnal. The highlight of this short survey was two new distributional records of flying squirrels for Merapoh Forest Complex. These two species were Spotted giant gliding squirrel (Petaurista elegans) and Temminck’s gliding squirrel (Petinomys setosus). Other gliding squirrels recorded in this survey include the Red Giant gliding squirrel (Petaurista petaurista), Horsfield’s gliding squirrel (Iomys horsfieldii) and Red-cheeked gliding squirrel (Hylopetes spadiceus). Apart from gliding squirrel, a total of eleven (11) species of other squirrels were also recorded within this survey. Continuous and systematic diversity surveys on gliding squirrels are needed as it is still understudied in Malaysia especially Merapoh.
Evaluation on the Potential of Hot Spring as Nature Tourism Attraction in Lojing Highlands, Kelantan, Peninsula Malaysia
Authors: Fiffy H S , Elia G , Nor Hizami H , Zulhazman H , Nordiana M N , Nor Akmar A A
Published: May 2021

Natural hot springs are a common occurrence in Malaysia. These natural hot springs occur when water seeps into the earth and is heated by magma and pressure causes the water to rise again as a heated pool or hot springs. Some locals believe that these natural hot springs have curative effects and can cure skin ailments such as rashes, pimples and fungi infections. Whether this is true or not remains to be scientifically proven, but these places have become a magnet for tourists and those seeking healing. Some of Malaysia’s natural hot springs have developed into modern tourists’ attractions with shops, rest houses, restaurants and changing rooms built nearby to accommodate visitors who are interested by this natural phenomenon and the best example is the Poring Hot Springs, in Ranau, Sabah. Consequently, the objective of this paper is to briefly highlight the potential of Lojing’s hot springs as nature tourism attraction for the state of Kelantan. This paper provides a broad insight into the demand for services and facilities, location and characteristics of Lojing’s geothermal and natural mineral water resources, the opportunities available to expand and establish new facilities and an indication of the success of Sabah’s developments with the potential to be replicated in Lojing. Based on the content analysis done using Leximancer, it is apparent that Lojing’s hot spring requires intervention in terms of strategies that aimed at increasing tourist satisfaction. It is suggested that the theme “leisure” to be concentrated as the pull factor for Lojing hot spring-based tourism.
A preliminary study of tourists and vendors perception on the development of tourism souvenirs using natural dye from plants
Authors: Hashim N I R , Md Salleh N A , Norazlimi N A , Rahman A A A , Pa’ee F
Published: May 2021

The souvenir industry encompasses both handmade and massive scale productions. Production of coloured textiles becomes one of the basic technologies in human civilization. Based on the traditional knowledge of Temuan community lived in Taman Negara Johor Gunung Ledang, this research aims to develop souvenir products with t-shirts by adding natural color from Curcuma longa and Lawsonia inermis Linn. In order to develop the products, some steps were taken into account included the selection of plants part, extraction method, selection of mordant and technique used, and dyeing process. The color of aqueous extraction from C. longa and L. inermis were deep yellow and deep red, respectively. However, the color obtained on the t-shirts was slightly different. The perception of vendors and tourists in Taman Negara Johor Gunung Ledang (Waterfall), Tangkak, Johor towards developed souvenir using natural dye from plants are done through random survey session by distributing the questionnaire to the 122 respondents. 120 (98.4%) respondents reacted positively towards the souvenirs developed from natural plants based dye.
Abundance of Aquatic Insects in Spatial Variation of Two Rivers in Perak, Malaysia
Authors: Hasmi N A , Norazlimi N A , Abd-Latip N F
Published: May 2021

The effect of physical factors on the abundance of aquatic insects has been studied in Kuala Woh and Lata Kinjang Rivers, Perak, Malaysia. The focuses are to identify the aquatic insect families, to compare the abundance of aquatic insects in both sampling areas and to investigate the effect of physical factors (water temperature, depth of water, canopy, and water velocity) of both places on the abundance of aquatic insects. The samples were collected by using aquatic net. Physical parameters; water velocity, water temperature, depth and canopy cover have been measured in situ and recorded. A total of 278 individuals classified into 6 orders and 9 families of aquatic insects were identified from two sampling sites. The largest percentage of samples collected is from order Plecoptera 62.6%, followed by Trichoptera 15.8%, Hemiptera 10.8%, Ephemeroptera 7.9%, Odonata 1.4% and Coleoptera 1.4%. The aquatic insects collected from Kuala Woh have the highest abundance of 214 individuals from 6 orders and 9 families compared to Lata Kinjang which only have 64 individuals from 5 orders and 6 families. Chi-square test value (23.494) indicated significant association between different sampling areas and abundance of aquatic insects, P value = 0.003 (p < 0.05). Kuala Woh has a moderate stream flow (0.17 m/s) of warm water (27°C), with 0.85 m depth and not covered by canopy. Lata Kinjang has faster stream flow (0.84 m/s) with the temperature of 24°C, 0.36 m depth and covered by canopy. The results reveal that the abundance of aquatic insects is high when water temperature increases, low water velocity, deeper water and the area that is not covered by canopy.
Microsatellite analysis of Rafflesia cantleyi from the Rafflesia Conservation and Interpretive Centre, Bersia Timur and Gerik Forest Reserve, Perak, Malaysia
Authors: Lee C T , Tnah L H , Humaira’ Z H , Nurul-Farhanah Z , Lee S L , Ng K K S , Ng C H , Nur-Nabilah A , Norlia B , Noorsiha A , Siti-Munirah M Y
Published: May 2021

Located at Bersia Timur, the Rafflesia Conservation and Interpretive Centre (RCIC) was initiated by the Forest Research Institute Malaysia (FRIM) and FELDA to boost research and conservation efforts of the iconic Rafflesia species in the state of Perak. It also plays a role in supporting the economy of local communities by promoting local eco-tourism, providing trainings to local tour-guides and involving them in conserving the Rafflesia population. As part of the R & D and conservation effort, genetic diversity assessment of Rafflesia cantleyi from RCIC and Gerik Forest Reserve (FR) was carried out. Bract samples from a total of eight and 35 R. cantleyi individuals of different flowering / anthesis stages were collected from RCIC and Gerik FR, respectively. We used nine polymorphic microsatellite markers for genotyping. Despite the small sample size (∼75% lesser compared with Gerik FR), the total number of alleles observed in RCIC is > 50% than that of Gerik FR, i.e., 33 compared to 57. The genetic diversity measure in terms of observed (Ho) and expected (He) heterozygosities from both sites are comparable (RCIC: Ho = 0.5298, He = 0.5347; Gerik FR: Ho = 0.5145, He = 0.5868). Our findings suggest that the R. cantleyi population in Gerik FR is a suitable source for future translocation activities.
A comparative study of antituberculosis activities of Tetracera macrophylla Wall. Ex Hook. f. &Thoms. stem fractions using different chromatographic stationary phases
Authors: Mazlun M H , Sabran S F , Abdullah Z , Parumasivam T
Published: May 2021

Mempelas (Tetracera macrophylla Wall. Ex Hook. f. & Thoms) is a climbing liana that has been used by several ethnics in Malaysia for its medicinal values. In regards to tuberculosis (TB) therapy, T. macrophylla has ethnobotanically demonstrated promising anti-TB activities. Current research aimed to determine the anti-TB activities of T. macrophylla stem fractions eluted from two different stationary phases via column chromatographic technique. T. macrophylla stems were extracted using semi-polar solvent via maceration method. Two portions of the extract were fractionated through column chromatography using Silica (Si) gel 60 and Mitsubishi Chemical Ion (MCI®) gel. Eluted fractions were monitored via pre-coated Si gel 60 F254 aluminium plates as thin-layer chromatography (TLC). Anti-TB bioassay were conducted via the employment of Tetrazolium Microplate Assay (TEMA) procedure. Fractionation of the extract has resulted in the elution of 12 and 16 combined fractions from MCI® gel and Si gel 60, respectively. TEMA result has revealed that none of the combined fractions eluted from MCI® gel inhibited the test organism, Mycobacterium tuberculosis H37Ra. On contrary, 7 of 16 fractions as eluted from Si gel 60 inhibited M. tuberculosis H37Ra at Minimum Inhibition Concentration (MIC) ranging from 400 to 800 µg/ml. The results from this study has led to the conclusion that Si gel 60 is a more suitable stationary phase to be used in fractionating plant extracts for TB research.
Transit Oriented Development (TOD) typology
Authors: Mohamad N F N , Fahmy-Abdullah M , Masrom M A N
Published: May 2021

Transit-Oriented Development (TOD) Typology is becoming increasingly significant as our planet urbanises. It promotes an environmentally sustainable development, eases mobility, increases real estate value, encourages healthy lifestyles with activities such as walking, and improves neighbourhood through place-making by making it safer. In short, TOD Typology makes a city worth staying in. Although there are a number of studies available, TOD which primarily focuses on developing countries is still undiscovered. This research paper aims to identify the TOD indicators and the mechanism of inter-modal stations to integrate various modes of transport in Bandar Penggaram, Batu Pahat. The method used in this research was mixed method using a survey, observation, and document review to obtain accurate data. A survey was conducted by distributing questionnaires to 370 respondents. The observation was carried out by assessing using a checklist in the research area. Meanwhile, the document review was conducted based on the document obtained from Majlis Perbandaran Batu Pahat (MPBP). Through the data analysis of the checklist assessment and document review regarding the identification of TOD indicators and mechanism of intermodal station via the SPSS software, the results indicated that density, land use, walkability and cyclability, access and accessibility, interchange stations and system integration are deemed suitable and have a great potential to improve the development of TOD typologies. These elements are useful and provide benefits to passengers or users, pedestrians, and cyclists. This paper would be beneficial as it provides a new insight and guidance for the government and the authorities to improve current practices and also for future research to conduct similar studies related to TOD typology.
Checklist of butterflies (Lepidoptera: Papilonoidea and Hesperioidea) in Gunung Pulai Forest Reserve, Johor
Authors: Rahman A A A , Maryati M
Published: May 2021

This survey was done to provide a checklist of butterflies in Gunung Pulai Forest Reserve, Johor Darul Takzim. Sampling were done between October 2017 to March 2018 for nine sampling days. Butterflies were caught using aerial net and baited traps. The traps were baited with a mixture of rotten bananas and pineapples. A total of 101 individuals comprising 61 species were obtained from this survey. Family Nymphalidae recorded the highest number of species with 30 species, followed by Lycaenidae with 16 species. The most dominant species was Ypthima horsfieldii humei (Nymphalidae) with eight individuals followed by Lexias pardalis dirteana (Nymphalidae) with six individuals. Out of the 61 species, 45 were singletons which accounts for 73.8% of the sample. The Shannon Diversity Index for the butterflies in this area is 3.884 with an Evenness value of 0.941. Three species are considered as new records for the state of Johor. Based on the high value of Shannon Diversity Index and the abundance of singletons, it can be concluded that Gunung Pulai Forest Reserve holds a high diversity of butterflies in the region.
The habitat preference of mangrove crabs in different mangrove forests of Penang, North Peninsular Malaysia
Authors: Salleh-Mukri M , Shuhaida S
Published: May 2021

Different crab assemblage compositions may result in distinct pathways in mangrove ecosystem function, attributed to specific preferences and habitat selection criteria by each crab species. This study assessed the preference of crabs to different mangrove forests at Balik Pulau, Penang, Malaysia across temporal scales of four months and spatial scales across three forests. Sites were characterized by Avicennia, Rhizophora and Bruguiera species. Crabs were sampled using hand-catch method, which was then preserved in 70% ethanol and identified to the lowest taxonomic level possible. Environmental variables were determined by in-situ and ex-situ analysis and comprised the collection of canopy cover, root cover, surface temperature, sediment salinity and organic matter data. PERMANOVA analysis showed there was a difference in crab abundance and environmental variables across Month and Forest (p < 0.05). SIMPER analysis revealed that the Grapsidae family dominated mangroves of Balik Pulau, with Perisesarma eumolpe and Perisesarma foresti found to be most abundant in Avicennia and Bruguiera forests respectively. However, in the Rhizophora forest, dominant crab species varied, with Parasesarma sp2. and Perisesarma indiarum found in high abundance in June and August, respectively. In October and December, however Perisesarma foresti was the major contributor to patterns observed in crab assemblage composition in Rhizophora forest. BEST correlation varied among month and forest, with different combinations of salinity, pH, canopy cover and root density explaining patterns in crab assemblages.
Response of scleractinian corals to nitrate enrichment in high and ambient seawater temperatures
Authors: Tengku-Mohd-Kamil T F K , Turner J R
Published: May 2021

Coral bleaching and mortality events have recently increased in frequency and severity in the whole world. Combined effects of natural and anthropogenic impacts were assumed to be the cause for coral’s health degradation. Sedimentation, urban waste, sewage discharge and agricultural activities are among the nutrient input for Malaysian waters, which can affect the coral reefs indirectly. In this study, photosynthetic performance of tropical corals under stresses were studied by exposing three common tropical scleractinian corals, Stylophora pistillata, Montipora digitata and Seriatopora hystrix to combination of different levels of high and ambient temperature and in a laboratory condition. Quantum yield fluorescence before, after stress and after recovery stage were recorded using a dark-adapted photochemical efficiency (Fv/Fm) methodology with a pulse-amplitude-modulation (PAM) chlorophyll fluorometer (WATER-PAM, Walz, Germany). Physical appearance of the corals were after the post-stress stages. The results showed that nutrient enrichment not have a synergistic effect, and that high temperatures alone significantly impact Fv/Fm values (three-way ANOVA, p > 0.05) for all coral species. Slow growing corals (S. pistillata) appeared to cope better with the high temperatures than the fast-growing corals (M. digitata and S. hystrix). Hence, that a nitrate concentration contributed as an intial response of the symbiont’s physiological changes, which can give more understanding on studying specific coral species resistance towards coral bleaching issues.
Comparison of Diversity and Community Structure of Aquatic Insects Based on Habitat Class in Johor
Authors: Zakaria M Z , Maryati M
Published: May 2021

Aquatic insects had been well used as a tool in monitoring water quality and this study is aimed to gauge their potential in Johor. The rapid development in the state of Johor may cause pollution to water resources that require a more efficient water quality monitoring program. The objectives of this study were to (i) collect, identify, determine and produce aquatic insect diversity data in selected rivers in Johor, (ii) relate the presence of aquatic insect diversity with some of the physical features of rivers in Johor. Seven sampling areas were selected based on their importance to local communities and geographical distribution: Taman Negara Johor Endau Rompin (PETA) (TNJER-PETA), Taman Hutan Lagenda Gunung Ledang (THLGL), Hutan Lipur Soga Perdana (HLSP), Hutan Lipur Gunung Belumut (HLGB), Hutan Lipur Sungai Bantang (HLSB), Hutan Lipur Gunung Pulai 1 (HLGP1) and Sungai Sayong Pinang. Insect samples were collected using a kick net method and slight modifocation made according to type of microhabitats. A total of 11,647 individuals of aquatic insects consisting of 68 families from nine orders were sampled. About 69% of insects collected were indicators of good water quality; among them are families Hydropsychidae from order Trichoptera, Baetidae from Order Ephemeroptera, and Simuliidae from Order Diptera. Based on family diversity analyzed using Shannon Index (H’), TNJER-PETA is recorded having the highest index (H’ = 3.215) followed by HLSP (H’ = 2.791) and HLGB (H’ = 2.482). Comparison made and based on physical characteristics, the study sites were classified into three categories (i) the most preferred sites by aquatic insects (HLSB, THLGL, HLGP1, and HLGB), (ii) intermediate preferred sites (TNJER-PETA and HLSP) and (iii) least preferred site (Sg. Sayong). In conclusion, community structure of benthic organisms were influenced by many factors such as presence of variety of microhabitat, predation, surrounding environments, food availability, physical and chemical characteristics of water. Moreover, higher heterogeneity of habitat promote high abundance and diversity of aquatic insects. Any changes happened that involves human interference in the habitats, will affect the abundance of aquatic insects. Last but not least, results suggested that the quality of river water in Johor can be monitored using insects as biological indicators due to the abundance, distribution, and rapid response of aquatic insects to environmental conditions.
Enhanced crystalline quality of non-polar a-plane AlGaN epitaxial film grown with Al-composition-graded AlGaN intermediate layer
Authors: Nasir Abbas , Zhang Xiong , Lu Liang , Zhang Jin , Lyu Jiadong , Cui Yiping
Published: May 2021

The non-polar a-AlGaN epitaxial film was successfully grown on the semi-polar r-sapphire substrate by metal-organic chemical vapor deposition technique. An Al-composition-graded AlxGa1−xN (x = 0.0 to 1.0) intermediate layer with varying film thickness from 260 to 695 nm was deposited between the high-temperature AlN layer and the non-polar a-AlGaN epitaxial film to enhance the morphological and crystalline quality. The non-polar a-AlGaN epitaxial films were investigated by using atomic force microscopy (AFM), high-resolution x-ray diffraction, photoluminescence (PL) spectroscopy and the Hall effect measurement techniques. The characterisation results indicate substantial improvements in surface morphology and crystalline quality for the non-polar a- AlGaN epitaxial film grown by adding an Al-composition-graded AlGaN intermediate layer. The surface roughness measured from AFM and the defect-related emission (yellow band) relative to the near-band-edge emission from PL spectra were decreased significantly by optimizing the layer thickness of the Al-composition-graded AlGaN layer. A relatively low background carrier concentration down to −4.4 × 

10

17

cm−3 was achieved from Hall effect measurement for the non-polar a-AlGaN epitaxial film.
Effects of implausible power plant lifetime assumptions on US federal energy system projected costs, greenhouse gas emissions, air pollution, and water use
Authors: Zacarias L Mathias , Grubert Emily
Published: May 2021

Climate change motivates rapid decarbonization of the energy sector, with a particular focus on decarbonizing and expanding the electricity system. Given multiple plausible pathways toward decarbonization, scenario-based analysis of potential energy futures is a common analytical approach in the field of macro-energy systems. Scenario analysis is particularly valuable for assessing multicriteria impacts and identifying potential unintended consequences, especially when policies focus on a specific indicator, like greenhouse gas emissions. In the United States (US), the federal government produces projections for the future US energy system using the National Energy Modeling System, published in an Annual Energy Outlook (AEO) that includes multiple economic and policy scenarios to inform decision making. Although AEO scenarios are not intended as predictions, they are widely used as contextual baselines for evaluating cost, pace, and environmental impacts of the energy transition. As the official energy system scenarios of the US, a wealthy, high-emissions country, AEO scenarios serve an anchoring function that influences perceptions of the relative implications of alternative energy transition strategies. This research shows that projected cost and environmental intensity of the US electricity system are surprisingly stable across AEO scenarios. Why? We show that by not incorporating business-as-usual license expiration and generator lifespans, AEO effectively assumes that power plants can run indefinitely, which overlooks major asset replacement costs and fleet turnover opportunities that would likely accelerate decarbonization. Assuming typical lifespans and licensed operating periods, roughly 700 gigawatts (GW) of fossil and nuclear electricity generation capacity beyond the 170 GW of retirements modeled in AEO2020’s reference case would be expected to close, with an estimated unmodeled replacement cost of 2019$1.3 trillion. This cost is similar to the projected cost impact of a $35/tonne carbon dioxide price. Macro-energy systems analysis can be improved with more attention to physical and infrastructural constraints in models.