bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcomes of Nonvigorous Neonates Born through Meconium-Stained Amniotic Fluid after a Practice Change to No Routine Endotracheal Suctioning from a Developing Country
Authors: Kumar Gunjana , Goel Srishti , Nangia Sushma , Ramaswamy Viraraghavan Vadakkencherry
Published: March 2022

Objective The International Liaison Committee on Resuscitation (ILCOR) 2015 gave a weak recommendation based on low certainty of evidence against routine endotracheal (ET) suctioning in non-vigorous (NV) neonates born through meconium-stained amniotic fluid (MSAF) and suggested for immediate resuscitation without direct laryngoscopy. A need for ongoing surveillance post policy change has been stressed upon. This study compared the outcomes of NV MSAF neonates before and after implementation of the ILCOR 2015 recommendation.

Study Design This was a prospective cohort study of term NV MSAF neonates who underwent immediate resuscitation without ET suctioning (no ET group, July 2018 to June 2019, n = 276) compared with historical control who underwent routine ET suction (ET group, July 2015 to June 2016, n = 271).

Results Baseline characteristics revealed statistically significant higher proportion of male gender and small for gestational age neonates in the prospective cohort. There was no significant difference in the incidence of primary outcome of meconium aspiration syndrome (MAS) between the groups (no ET group: 27.2% vs ET group: 25.1%; p = 0.57). NV MSAF neonates with hypoxic ischemic encephalopathy (HIE) was significantly lesser in the prospective cohort (no ET group: 19.2% vs ET group: 27.3%; p = 0.03). Incidence of air leaks and need for any respiratory support significantly increased after policy change. In NV MSAF neonates with MAS, need for mechanical ventilation (MV) (no ET group: 24% vs ET group: 39.7%; p = 0.04) and mortality (no ET group: 18.7% vs ET group: 33.8%; p = 0.04) were significantly lesser.

Conclusion Current study from a developing country indicates that immediate resuscitation and no routine ET suctioning of NV MSAF may not be associated with increased risk of MAS and may be associated with decreased risk of HIE. Increased requirement of any respiratory support and air leak post policy change needs further deliberation. Decreased risk of MV and mortality among those with MAS was observed.

Key Points
Pathologic Mandibular Fracture Associated with Bilateral Dentigerous Cysts in a Dog
Authors: Jones Rebecca Lauren , Gauthier Olivier , Vallefuoco Rosario
Published: March 2022

This report describes the management and computed tomographic (CT) follow-up of a pathologic fracture of the mandibular body associated with bilateral dentigerous cysts in a 16-month-old Boxer. Bilateral, rostral, mandibular lesions consistent with dentigerous cysts were identified by intraoral radiography and CT. The left cyst was associated with an open, mildly displaced mandibular fracture. Treatment of the cystic lesions consisted of surgical exposure, extraction of embedded teeth, curettage of the cyst lining, and placement of demineralized bone matrix. Reduction and stabilization of the fracture were achieved by interdental wiring combined with an intraoral splint. Follow-up examination and CT imaging were performed at 8, 18, and 85 weeks postoperatively. Complete fracture healing and resolution of both cystic lesions were confirmed at 18 weeks with no recurrence evident at 85 weeks. No complications were encountered. To the authors' knowledge, this is the first case report of a pathologic mandibular fracture secondary to a dentigerous cyst in a dog, documenting the healing of dentigerous cysts via CT with progressive replacement of demineralized bone matrix by new osseous growth. Surgical treatment of the pathologic mandibular fracture and the bilateral dentigerous cysts resulted in an excellent clinical outcome.
Enterogenous Cyst and Glioblastoma: A Brief Histopathological Review of Two Uncommon Cystic Lesions of the Central Nervous System
Authors: Cambruzzi Eduardo , Ferreira Nelson Pires , Ferreira Marcelo Paglioli , Gago Guilherme , Bertinatti João Pedro Pattussi
Published: March 2022

Intracranial cystic lesions are common findings in cerebral imaging and might represent a broad spectrum of conditions. These entities can be divided into nonneoplastic lesions, comprising Rathke cleft cyst, arachnoid cyst, and colloid cyst, as well as neoplastic lesions, including benign and malignant components of neoplasms such as pilocytic astrocytoma, hemangioblastoma, and ganglioglioma. Surgical resection and histological evaluation are currently the most effective methods to classify cysts of the central nervous system. The authors report two uncommon cases presenting as cystic lesions of the encephalic parenchyma—a enterogenous cyst and a glioblastoma—and discuss typical histological findings and differential diagnosis.
Aktivieren, motivieren, früher zurück in die Selbstständigkeit
Authors: Betz Ulrich
Published: March 2022

Eine bessere Versorgungsqualität war das Ziel des interdisziplinären Forschungsprojektes PROMISE an der Universitätsmedizin Mainz. Die Buchstaben stehen für PROzessoptiMierung durch Interdisziplinäre, SEktorübergreifende und ganzheitliche Versorgung am Beispiel von Hüft- und Kniegelenkarthrosen. Physiotherapeut Dr. Ulrich Betz ist Mitinitiator der mittlerweile abgeschlossenen Studie, deren Ergebnisse belegen: Besser versorgte und früher aktivierte Patient*innen haben weniger Komplikationen und sind früher wieder selbstständig. Wie das gelingt, verrät er im Interview.
Modifications in the magnetocaloric effect owing to composition changes in Gd2In1−x
Ge
x (0 ≤ x ≤ 0.2) system of compounds
Authors: Sharma Sanjay , Kumar Pramod
Published: March 2022

In this paper, we report the variations observed in magnetothermal, magnetocaloric, and magnetic properties of the Gd2In1−xGex (0 ≤ x ≤ 0.2) system of compounds concerning the changes in substitution of Ge. Changes have been recorded in a temperature sweeping range of 2-300 K while the magnetic field was increased from 0 to a maximum of 5 T. All the compositions set into the Ni2In-type hexagonal structure and no structural changes are observed with the change in the value of x. Though the transition temperature values, which are TC ≈ 191 K and TN ≈ 100 K in case of x = 0, have only subtle shifts with the Ge substitution yet promising changes have been observed in the magnetocaloric effect. At x = 0.2 the isothermal magnetic entropy variation peak touches the value of 2.5 J/kg − K around TN in a field change from 0 to 5 T. This showcases that the compounds reported have a worthy place within the bracket of magnetocaloric compounds.
Magnetization process of cubic Fe3O4 submicron particles studied by polarized small-angle neutron scattering
Authors: Nomura Eiji , Chiba Momoko , Matsuo Sakoto , Noda Chiaki , Kobayashi Satoru , Manjanna Jayappa , Kawamura Yukihiko , Ohishi Kazuki , Hiroi Kosuke , Suzuki Jun-ichi
Published: March 2022

We report results of polarized small-angle neutron scattering (SANS) experiments at T = 10 K and 300 K for cubic Fe3O4 submicron-sized particles, where formation of a complex spin vortex is expected. Magnetic SANS intensities of magnetization components in the direction perpendicular and parallel to the magnetic field were observed to change significantly at around the coercivity. Magnetization components parallel to the field minimizes around the coercivity both at T = 10 K and 300 K, whereas those perpendicular to the magnetic field maximizes near the coercivity and the maximum value differ greatly, depending on the temperature. Based on results of micromagnetic simulations, the observed SANS intensities were interpreted as due to magnetic structural changes from a flower to a spin vortex state and gradual tilting of a vortex core from the external field to magnetocrystalline anisotropy axes at low fields.
Half-life and initial Solar System abundance of
146
Sm determined from the oldest andesitic meteorite
Authors: Fang Linru , Frossard Paul , Boyet Maud , Bouvier Audrey , Barrat Jean-Alix , Chaussidon Marc , Moynier Frederic
Published: March 2022

Significance

146
Sm-
142
Nd radioactive systematics can provide constraints on the timing of early differentiation processes on Earth, Moon, and Mars. The uncertainties related to the initial abundance and half-life of the extinct isotope
146
Sm impede the interpretation of the
146
Sm-
142
Nd systematics of planetary materials. The accurate determinations of Sm, Nd, and Mg isotopic compositions of the oldest “andesitic” achondrite Erg Chech 002 (EC 002) define a crystallization age of 1.8 Myr after the formation of the Solar System and provide the most accurate and reliable initial ratio of
146
Sm/
144
Sm for the Solar System at 0.00840

±

0.00032 using a
146
Sm half-life of 103 Ma, making EC 002 an anchor for
146
Sm-
142
Nd systematics for Earth and planetary materials.
Lexical bundles in formulaic interpreting
Authors: Li Yang , Halverson Sandra L.
Published: March 2022

Inspired by Henriksen (2007), this article investigates some key
characteristics of formulaic interpreting, understood as the recurrent use of linguistic formulae in interpreted texts. Using a
Chinese-English corpus of consecutive interpreting in the political setting (CICPPC), the study quantitatively investigates some
features of 4-gram lexical bundles in interpreted text, i.e., their discourse functions and relationships to the source text, and
qualitatively studies characteristics of specific instances of lexical bundles. The patterns are described both in terms of
equivalence, shifts, and additions, as well as ‘constraints on formulaicity,’ a generalization that captures the tension involved
between frequency-driven selection and the need to establish a translational relationship. It is suggested that equivalence
typical of form-based rendition and addition typical of meaning-based rendition are subject to lower constraints, while greater
constraints pertain in the case of shifts.
Dynamics of the Entanglement Zero Modes in the Haldane Model under a Quantum Quench
Authors: Ji Heng-Xi , Mo Lin-Han , Wan Xin
Published: March 2022

We investigate evolution of entanglement spectra of the Haldane model for Chern insulators upon a sudden quench within the same topological phase. In particular, we focus on the location of the entanglement spectrum crossing, which signifies the bulk topology. It is shown that the coplanarity condition for the pseudomagnetic field of the model, which can be used to determine the crossing in the equilibrium case, needs to be relaxed. We analytically derive the non-equilibrium condition with the help of an edge-state wave function ansatz and a dynamically induced length-scale cutoff. With spectral analyses, it is realized that the oscillatory behavior of the crossing is dominated by the interband excitations at the van Hove singularities.
Nonlinear Generation of Perfect Vector Beams in Ultraviolet Wavebands
Authors: Li Hui , Liu Haigang , Yang Yangfeifei , Lu Ruifeng , Chen Xianfeng
Published: March 2022

Perfect vector beams are a class of special vector beams with invariant radius and intensity profiles under changing topological charges. However, with the limitation of current devices, the generation of these vector beams is limited in the visible and infrared wavebands. Herein, we generate perfect vector beams in the ultraviolet region assisted by nonlinear frequency conversion. Experimental and simulation results show that the radius of the generated ultraviolet perfect vector beams remains invariant and is thus independent of the topological charge. Furthermore, we measure the power of the generated ultraviolet perfect vector beams with the change of their topological charges. This study provides an alternative approach to generating perfect vector beams for ultraviolet wavebands and may promote their application to optical trapping and optical communication.
Recent Advances in Moiré Superlattice Structures of Twisted Bilayer and Multilayer Graphene
Authors: Li Xiao-Feng , Sun Ruo-Xuan , Wang Su-Yun , Li Xiao , Liu Zhi-Bo , Tian Jian-Guo
Published: March 2022

Twisted bilayer graphene (TBG), which has drawn much attention in recent years, arises from van der Waals materials gathering each component together via van der Waals force. It is composed of two sheets of graphene rotated relatively to each other. Moiré potential, resulting from misorientation between layers, plays an essential role in determining the band structure of TBG, which directly relies on the twist angle. Once the twist angle approaches a certain critical value, flat bands will show up, indicating the suppression of kinetic energy, which significantly enhances the importance of Coulomb interaction between electrons. As a result, correlated states like correlated insulators emerge from TBG. Surprisingly, superconductivity in TBG is also reported in many experiments, which drags researchers into thinking about the underlying mechanism. Recently, the interest in the atomic reconstruction of TBG at small twist angles comes up and reinforces further understandings of properties of TBG. In addition, twisted multilayer graphene receives more and more attention, as they could likely outperform TBG although they are more difficult to handle experimentally. In this review, we mainly introduce theoretical and experimental progress on TBG. Besides the basic knowledge of TBG, we emphasize the essential role of atomic reconstruction in both experimental and theoretical investigations. The consideration of atomic reconstruction in small-twist situations can provide us with another aspect to have an insight into physical mechanism in TBG. In addition, we cover the recent hot topic, twisted multilayer graphene. While the bilayer situation can be relatively easy to resolve, multilayer situations can be really complicated, which could foster more unique and novel properties. Therefore, in the end of the review, we look forward to future development of twisted multilayer graphene.
John Ambrose Fleming’s early measurement of the skin effect in round wires
Authors: Smith Glenn S
Published: March 2022

The electromagnetic skin effect was a subject of interest to prominent physicists during the second half of the nineteenth century. By the end of the century, the theoretical analysis for this phenomenon was well developed, but accurate quantitative experimental results lagged behind. The subject of this paper is one of the early experiments performed to confirm the theory, specifically, measurements of the increase in the electrical resistance of a round wire with increasing frequency due to the skin effect. This elegant experiment was performed by John Ambrose Fleming, a student of James Clerk Maxwell and a pioneer in early wireless communication. The presentation in this paper is intended to complement theoretical treatments of the skin effect that are often part of instruction on electromagnetic theory and also to provide historical perspective for such treatments.
Dual-band electromagnetically induced transparent metamaterial with slow light effect and energy storage
Authors: Zheng Shuquan , Ma Mengshi , Lv You , Fu Tao , Peng Lin , Zhao Qixiang
Published: March 2022

The realization of electromagnetically induced transparency (EIT) on metamaterials has special properties, such as strong slow-light, frequency-selection and so on, which have allowed EIT to be widely used in the fields of slow-light, optical storages and filters. In this paper, a metamaterial with two pairs of split ring resonators and one cut-wire is designed to achieve dual-band EIT effect at 0.5–2.14 GHz and 0.4–2.10 GHz with independently tunable bandwidths of 1.64 GHz and 2.7 GHz, respectively. The coupled Lorentz model is adopted to principally study the coupling characteristics between dark and bright modes. It is shown that the coupling strength between the dark and bright modes could be modulated by the coupling distance, which make the dual-band transparent window could be independently modulated by only changing the coupling distance between the bright and dark mode. The group delay and energy storage are also simulated by setting the Gaussian pulse signal passing through the EIT structure. The results show that the group delay of the designed EIT structure is 16.9 times that of the same thickness of dielectric material. The manufactured metamaterial is tested in a microwave anechoic chamber. The experimental and theoretical results are well consistent. These results could be beneficial for the development of EIT research toward some up-and-coming novel slow-light, optical storage, sensor and optical filter applications.
Effect of non-uniform magnetic field on radial oscillation of electron beam in a low-magnetic-field foilless diode
Authors: Zhang Guangshuai , Sun Jun , Wu Ping , Shi Yanchao , Fan Zhiqiang , Hua Ye , Tan Nongchao
Published: March 2022

A theory regarding a non-uniform magnetic field with a parallel gradient is presented. The research results show that a proper non-uniform magnetic field can greatly reduce the transverse momentum of an electron beam and even eliminate its gyration motion, and it depends on the gradient of the magnetic field and the phases of electrons entering and leaving the local magnetic field region. Thus, a magnetic field that decreases along the axial direction is proposed to suppress the radial oscillation of the electron beam. However, in the drift tube, the suppression of the radial oscillation is not obvious, because the large phase differences among electrons lead to a mismatch between the electron beam and the non-uniform magnetic field. Further studies found that the non-uniform magnetic field applied in the anode-cathode gap can not only reduce the phase differences among electrons, but also effectively transform the transverse momentum of the electron beam into its axial momentum. The results obtained by PIC simulations and experiments consistently confirm that the non-uniform magnetic field can significantly suppress the radial oscillation of the electron beam in a low-magnetic-field foilless diode.
The Gutzwiller conjugate gradient minimization method for correlated electron systems
Authors: Ye Zhuo , Fang Yimei , Zhang Han , Zhang Feng , Wu Shunqing , Lu Wen-Cai , Yao Yong-Xin , Wang Cai-Zhuang , Ho Kai-Ming
Published: March 2022

We review our recent work on the Gutzwiller conjugate gradient minimization method, an ab initio approach developed for correlated electron systems. The complete formalism has been outlined that allows for a systematic understanding of the method, followed by a discussion of benchmark studies of dimers, one- and two-dimensional single-band Hubbard models. In the end, we present some preliminary results of multi-band Hubbard models and large-basis calculations of F2 to illustrate our efforts to further reduce the computational complexity.
Tailoring porous/filament silicon using the two-step Au-assisted chemical etching of p-type silicon for forming an ethanol electro-oxidation layer
Authors: Volovlikova Olga , Shilyaeva Yulia , Silakov Gennady , Fedorova Yulia , Maniecki Tomasz , Gavrilov Sergey
Published: March 2022

In this paper, we are reporting on the fabrication of a porous silicon/Au and silicon filament/Au using the two-step Au-assisted chemical etching of p-type Si with a specific resistivity of 0.01, 1, and 12 Ω·cm when varying the Au deposition times. The structure analysis results show that with an increasing Au deposition time of up to 7 min, the thickness of the porous Si layer increases for the same etching duration (60 min), and the morphology of the layer changes from porous to filamentary. This paper shows that the uniform macro-porous layers with a thickness of 125.5–171.2 μm and a specific surface area of the mesopore sidewalls of 142.5–182 m2·g−1 are formed on the Si with a specific resistivity of 0.01 Ω·cm. The gradient macro-porous layers with a thickness of 220–260 μm and 210–290 μm, the specific surface area of the mesopore sidewalls of 3.7–21.7 m2·g−1 and 17–29 m2·g−1 are formed on the silicon with a specific resistivity of 1 and 12 Ω·cm, respectively. The por-Si/Au has excellent low-temperature electro oxidation performance with ethanol, the activity of ethanol oxidation is mainly due to the synergistic effect of the Au nanoparticles and porous Si. The formation mechanism of the uniform and gradient macro-porous layers and ethanol electro-oxidation on the porous/filament silicon, decorated with Au nanoparticles, was established. The por-Si/Au structures with perpendicularly oriented pores, a high por-Si layer thickness, and a low mono-Si layer thickness (with a specific resistivity of 1 Ω·cm) are optimal for an effective ethanol electro-oxidation, which has been confirmed with chronoamperometry measurements.
Gas sensing devices based on two-dimensional materials: a review
Authors: Wang Boran , Gu Yi , Chen Lin , Ji Li , Zhu Hao , Sun Qingqing
Published: March 2022

Gas sensors have been widely utilized penetrating every aspect of our daily lives, such as medical industry, environmental safety testing, and the food industry. In recent years, two-dimensional (2D) materials have shown promising potential and prominent advantages in gas sensing technology, due to their unique physical and chemical properties. In addition, the ultra-high surface-to-volume ratio and surface activity of the 2D materials with atomic-level thickness enables enhanced absorption and sensitivity. Till now, different gas sensing techniques have been developed to further boost the performance of 2D materials-based gas sensors, such as various surface functionalization and Van der Waals heterojunction formation. In this article, a comprehensive review of advanced gas sensing devices is provided based on 2D materials, focusing on two sensing principles of charge-exchange and surface oxygen ion adsorption. Six types of typical gas sensor devices based on 2D materials are introduced with discussion of latest research progress and future perspectives.
3D printing auxetic draft-angle structures towards tunable buckling complexity
Authors: Liu Yuheng , Lei Ming , Peng Linlong , Lu Haibao , Shu Dong-Wei
Published: March 2022

With the development of 3D printing technology, auxetic structures have attracted extensive attention due to their unusual mechanical properties. In this study, we design a 3D printed auxetic structure using 2D draft angles to achieve a tunable out-of-plane double hyperbolic buckling behavior by effectively continuously varying stiffness across thickness. The influences of radii and draft angles on the buckling behaviors of the 3D printed draft-angle auxetic structures are studied by finite element method. The constitutive relationships between stress, strain, radius, and draft angle have been formulated and discussed to identify the working principle behind the mechanical performance of draft-angle auxetic structures. Finally, the buckling behavior is modelled by a laminate structure, and the accuracy of these analytical results has then been verified by experiment. This study is expected to provide a design guideline for achieving tunable buckling behavior of auxetic structures via the novel stress mismatch of draft angles and thus continuously varying stiffness along the thickness direction. The current work constitutes an initial attempt to realize the tunability of the 3D out of plane deformation of 2D plane structures under in-plane compression.
Temperature-dependent effect of modulation in graphene-supported metamaterials
Authors: Morozov Yevhenii M , Lapchuk Anatoliy S , Protsak Iryna S , Kryuchyn Andriy A , Nevirkovets Ivan P
Published: March 2022

We report on a novel effect of temperature-dependent modulation in graphene-supported metamaterials. The effect was observed during the theoretical analysis of a model graphene-supported electro-optical modulator having silicon dioxide (SiO2) or hafnium dioxide (HfO2) as a buffer dielectric layer. Comparative analysis of the two materials showed that they provide approximately the same maximum values for transmission and reflection modulation depths. However, in the case of a HfO2 buffer layer, a lower chemical potential of the graphene is required to achieve the maximum value. Moreover, theoretical calculations revealed that a lower gate voltage (up to 6.4 times) is required to be applied in the case of a HfO2 layer to achieve the same graphene chemical potential. The graphene layer was found to possesses high absorption (due to the additional resonance excitation) for some values of chemical potential and this effect is extremely temperature dependent. The discovered modulation effect was demonstrated to further increase the transmission modulation depth for the simple model structure up to 2.7 times (from 18.4% to 50.1%), while for the reflection modulation depth, this enhancement was equal to 2.2 times (from 24.4% to 52.8%). The novel modulation effect could easily be adopted and applied over a wide range of metadevices which would serve as a quick booster for the development of related research areas.
Topological nodal line semimetal in an all-sp
2 monoclinic carbon
Authors: Khan Muhammad Rizwan , Bu Kun , Wang Jian-Tao
Published: March 2022

Topological nodal line semimetal is an exotic class of quantum materials featuring the continuous line of nodes inside the first Brillouin zone. Here we identify by systematical ab initio calculations a new all-sp
2 hybridized carbon allotrope with monoclinic C2/c

(

C

2
h

6

)

symmetry which is termed as bcm-C16. Total energy calculations show that our proposed bcm-C16 carbon is energetically comparable to or stable than the previously proposed bco-C16, bct-C16, and oP16 carbon. Its dynamical stability has been confirmed by phonon mode calculations. Detailed analysis of the electronic properties show that bcm-C16 carbon is a topological nodal line semimetal with a single closed nodal ring around the Γ high symmetric point, protected by spatial inversion

(

P

)

and time-reversal

(

T

)

symmetry. When the nodal ring is projected onto the (001) surface, a topologically protected drumhead-like surface state can be seen inside or outside the nodal ring depending on the different surface terminations. Moreover, we also examined the tensile-strain robustness of the electronic properties of bcm-C16 carbon. The nodal ring is robust under a tensile-strain along the crystalline x- and z-directions up to 20%. In addition, the simulated x-ray diffraction pattern (XRD) of bcm-C16 carbon matches with the experimental pattern found in the detonation and chimney soot experiment. The present proposal has enriched the family of carbon allotropes with topological nodal lines, and pave the way for further theoretical and experimental studies.
Studying the potential of QQq at finite temperature in a holographic model *
Authors: Chen Xun , Yu Bo , Chu Peng-Cheng , Li Xiao-hua
Published: March 2022

Using gauge/gravity duality, we investigate the string breaking and dissolution of two heavy quarks coupled to a light quark at finite temperature. It is found that three configurations of QQqexist with the increase in separation distance for heavy quarks in the confined phase. Furthermore, string breaking occurs at the distance

(

) for the decay mode

. In the deconfined phase, QQq melts at a certain distance and then becomes free quarks. Finally, we compare the potential of QQq with that of

, and it is found that

is more stable than QQqat high temperatures.
A data-driven methodological routine to identify key indicators for social-ecological system archetype mapping
Authors: Pacheco-Romero Manuel , Vallejos María , Paruelo José M , Alcaraz-Segura Domingo , Torres-García M Trinidad , Salinas-Bonillo María J. , Cabello Javier
Published: March 2022

The spatial mapping of social-ecological system (SES) archetypes constitutes a fundamental tool to operationalize the SES concept in empirical research. Approaches to detect, map, and characterize SES archetypes have evolved over the last decade towards more integrative and comparable perspectives guided by SES conceptual frameworks and reference lists of variables. However, hardly any studies have investigated how to empirically identify the most relevant set of indicators to map the diversity of SESs. In this study, we propose a data-driven methodological routine based on multivariate statistical analysis to identify the most relevant indicators for mapping and characterizing SES archetypes in a particular region. Taking Andalusia (Spain) as a case study, we applied this methodological routine to 86 indicators representing multiple variables and dimensions of the SES. Additionally, we assessed how the empirical relevance of these indicators contributes to previous expert and empirical knowledge on key variables for characterizing SESs. We identified 29 key indicators that allowed us to map 15 SES archetypes encompassing natural, mosaic, agricultural, and urban systems, which uncovered contrasting land sharing and land sparing patterns throughout the territory. We found synergies but also disagreements between empirical and expert knowledge on the relevance of variables: agreement on their widespread relevance (32.7% of the variables, e.g. crop and livestock production, net primary productivity, population density); relevance conditioned by the context or the scale (16.3%, e.g. land protection, educational level); lack of agreement (20.4%, e.g. economic level, land tenure); need of further assessments due to the lack of expert or empirical knowledge (30.6%). Overall, our data-driven approach can contribute to more objective selection of relevant indicators for SES mapping, which may help to produce comparable and generalizable empirical knowledge on key variables for characterizing SESs, as well as to derive more representative descriptions and causal factor configurations in SES archetype analysis.
Theophylline extended-release monolithic matrix comprising natural rubber latex as binder
Authors: Chaiya P , Phaechamud T
Published: March 2022

A major component of polymer in natural rubber latex (NRL) obtained from Hevea brasiliensis consists of poly-cis-1,4-isoprene. Poly-cis-1,4-isoprene exhibited interesting physical properties suitable for possible use as a binder in pharmaceutical solid dosage forms such as monolithic matrix tablet. The aim of this study was to study the feasibility of using NRL as the binder in theophylline anhydrous (THE)-incorporated monolithic matrix tablet in comparison with polyvinyl pyrrolidone K-30 (PVP-30). Physical properties of granules and tablets fabricated with wet granulation and tableting process, in vitro drug release test and release kinetic model were investigated and compared with those prepared using PVP-K30 as a binder. THE-incorporated monolithic matrix tablet was successfully fabricated with wet granulation and tableting process using NRL or PVP-K30 as binder. Granules and tablets of monolithic matrix tablet using NRL as a binder exhibited similar physical properties to those of tablet prepared using PVP-K30 as a binder. In addition, the controlled THE release with diffusion mechanism were presented in both formulations. Surprisingly, the addition of sodium bicarbonate in THE monolithic matrix tablets employing NRL as a binder could also prolong the drug release.
Prediction of crosslink density of prevulcanised latex using NIR Spectroscopy based on combination of fractional order derivative (FOD) and variable selection methods
Authors: Lim C H , Posom J , Sirisomboon P
Published: March 2022

Rapid method in measurement of crosslink density is required in factory. The objective of this study was to develop the prediction model of crosslink densities based on near infrared (NIR) spectroscopy method. The prediction models were developed using partial least squares regression (PLSR) with spectral pre-treatment of fractional order derivatives (FOD) and variable selection methods including successive project algorithm (SPA) and genetic algorithm (GA). The result demonstrated that prevulcanised (PV) latex model had higher accuracy than that of PV50 latex model. Effective model in predicting crosslink densities of PV and PV50 latices could be pre-processed with FOD=1 and 0.75, respectively. The prediction model generated with full wavelength had the standard error of cross validation (SECV) of 3.21% and 3.52%, respectively. The model performance of PV latex could improve with variable selection method of GA which reduced the SECV from 3.21% to 3.17% and number of wavelengths reduced from 1059 to 937. The model performance of PV50 could not reduce by using the variable selection method. However, the GA could reduce the number of wavelengths from 1059 to 216.
Deciphering the discoloration in the manufacturing of natural rubber
Authors: Sakdapipanich J
Published: March 2022

Many naturally occurring color components, especially non-rubber components, are present in natural rubber (NR) latex, limiting some NR applications, particularly for light-colored NR products in high demand. Non-rubber components, like lipids and proteins, can be removed from NR to reduce its yellow color. This study looked at the factors that influence the yellow index (YI) in NR and NR latex discoloration techniques. Proteins were a crucial factor directly determining the YI of NR. Thus, increasing the number of centrifugation washings, speed, and time was used to remove proteins to minimize the YI of NR. Percentage of total solid content (% TSC) of field NR latex, the blend ratio between cream rubber and skim latex, or bottom fraction from fresh-field NR latex collected from centrifugation process, were also important factors. The addition of sodium metabisulphites as a polyphenol oxidase (PPO)-reducing agent reduced the YI significantly. The oxidative breakdown of endogenous non-rubber components at high temperatures was also confirmed to serve the increase in YI value due to air-drying conditions of NR.
Near infrared spectroscopy and machine learning classifier of crosslink density level of prevulcanized natural rubber latex
Authors: Sirisomboon P , Lim C H , Posom J
Published: March 2022

By toluene swell index for cross link density level of prevulcanized (PV) rubber latex knowledge, toluene swell of PV latex is measured for trading and production management. Therefore, aim of this research is to use the Fourier transform near infrared (FT-NIR) spectroscopy with machine learning to classify different cross link density levels by toluene swell index including, Unvulcanized (U) (> 160%swell), Lightly vulcanized (L) (100-160%swell), Moderately vulcanized (M) (80-100%swell), Fully vulcanized (F) (< 80%swell) of prevulcanized (PV) natural rubber latex of raw PV latex and 50% solids content PV latex (PV50). The result shows that toluene swell index of rubber prevulcanized latex could be 91.8% correct classified into L group and M group using PV50 MSC pretreated spectra with PLS-DA classifier. Unfortunately, sample obtained for this experiment were loss of U and F groups. In future, to develop the robust model, the sample of all crosslink density levels should be collected.
Study of nylon textile-reinforced natural rubber composite
Authors: Choosang N , Smitthipong W
Published: March 2022

This study focuses on the production of nylon-reinforced natural rubber composites. In general, technical textiles serve as reinforcement and strength materials for a wide range of applications in rubber/textile composites. The adhesion between rubber and nylon is the most important factor affecting the assembly process and the strength of the finished product. The results showed that natural rubber reinforced with nylon textiles can be efficiently prepared by splicing a single layer of nylon fabric between two layers of rubber. The nylon textile-reinforced natural rubber composite was characterized by tensile testing machines and rubber curing characteristics, etc. The main result showed that the mechanical properties of rubber/nylon composites were higher than those of pure rubber. From the experimental results, it was found that nylon fabric can strengthen the natural rubber composite material for use with car tires.
Effect of potassium oleate on chemical structure-compression relationship of natural rubber foam
Authors: Kunklang P , Smitthipong W
Published: March 2022

Rubber foam-based products, such as mattresses, pillows, and cushions, are becoming increasingly popular. Rubber foam's formulation is still being developed to improve the properties, because of its wide range of applications. Potassium oleate is a surfactant for producing the rubber foam, although it can be used in different concentrations to prepare the different properties of rubber foam. The Dunlop method was used in this work, due to its simplicity and easy-to-use in the foam preparation. The effect of potassium oleate, which was used as a foaming agent, was investigated in this study by reducing the amount of potassium oleate. The density, compression, and Fourier transform infrared (FTIR) spectroscopy results showed that both density and compression of foam samples with half amounts of potassium oleate are higher than those of control sample with normal amounts of potassium oleate. Moreover, the FTIR result revealed a significant change in spectra with the reductions of potassium oleate contents. Therefore, rubber foam formulations are still developed to provide the optimum properties for suitable applications.
Study of particle size of natural latex/polysaccharide composite
Authors: Wongphul K , Smitthipong W
Published: March 2022

The natural additive especially polysaccharide is interested in polymer composite field because it can be biocompatibility, biodegradability, non-toxic, low cost and easy to find. In addition, it should be used to reinforce the polymer matrix and to reduce the cost of material. This work focused on the comparison of particle size of natural latex with and without polysaccharide. Besides, the particle size of natural latex composite with polysaccharide was also investigated in various concentrations of polysaccharide. The natural latex with 5 wt.% of alginate represented the biggest particle size due to the agglomeration of rubber molecule with polysaccharide. The particle size of polymer latex is an important parameter to better understand the interaction between polymer and filler in the polymer composite.
Evaluation on physicochemical properties and stability of Thanaka bark powder for natural face powder products
Authors: Hnin N Y , Kanlayavattanakul M
Published: March 2022

Thanaka (Hesperethusa crenulata Roem.) has been traditionally applied as cosmetics in Myanmar and the northern of Thailand [1] and exhibited anti-oxidant, anti-inflammatory, anti-microbial, skin lightening, and sun protection properties [1-4]. Thanaka’s specifications for cosmetic development are sparse to be presented, although its flowability was reported [1]. Of which, the bark was more suitable than the stem for solid dosage form development [1]. Thus, this study was aimed to assess the physicochemical properties and stability of Thanaka bark powder. The yellowish light brown powder (L* = 75.63 ± 0.01, a* = 5.58 ± 0.02 and b* = 23.45 ± 0.02) (Figure 1A) with bulk and tapped densities of 0.25 ± 0.00 and 0.29 ± 0.00 g/mL, was able to absorb water and oil (17.31 ± 0.77% and 13.39 ± 0.29%). The powder was ICP-MS proved to be uncontaminated with heavy metals prohibited for cosmetics. The powder morphology was plate-like crystals with fractured as SEM observed (Figure 1B). Thermal properties examined by DSC resulted in glass transition, crystallization and melting temperatures of 66.43, 70.25 and 73.39°C, with 51.32 ± 4.13% of crystallinity by XRD. The color (ΔE ≤ 1.43 ± 0.04), morphology, thermal properties, water absorption capacity and oil absorption capacity slightly shifted following to 3-month storage under ambient temperature and 45°C.
Utilization of lignin extracted from Thai ago-waste as UV-blocking agent for BG-lignin/PLA composite films
Authors: Wijaranakul P , Hararak B , Winotapun C , Wannid P , Chotirotsukon C , Laosiripojana W
Published: March 2022

The improving properties of poly(lactic acid), PLA, by utilizing natural resources attracted great intrigue to make such a green composite material that can be used as a commercial product in human life [1]. Lignin is one of biopolymer that can be used as bio-based filler and multifunctional bio-additive in a polymer composite. The most exciting properties of lignin that can be provided in a polymer composite is UV absorption and anti-oxidation [2]. In this current study, organosolv lignin extracted from sugarcane bagasse (BG-lignin) was utilized as multifunctional bio-additive in PLA for improving the UV absorption. The physicochemical and thermal properties of BG-lignin were determined using several techniques including SEM, GPC, quantitative 31P NMR, and DSC. BG-lignin at different loading contents (0.1, 0.2, 0.5, and 1 wt.%) was mixed with PLA via melt-extrusion. The attained compounds were converted to composite films via blown film extrusion. With the 0.5 wt.% loading content, the PLA composite films (0.5BG-lignin/PLA) absorbed almost all UV radiation which exhibits almost 70% blocking of UVB. The onset oxidation temperature of the PLA/0.5BG composite film increased by 34% as compared to that of the neat PLA film. Adding of BG-lignin enhanced tensile strength and Young’s modulus but did not favour to elongation at break.
The validation HPLC method for determination of gambogic acid in gamboge resin
Authors: Khaing E M , Jitrangsri K , Mahadlek J , Sukonpan C , Phaechamud T
Published: March 2022

Gambogic acid obtained from plant resin of Garcinia species has anticancer properties. This study focuses on the development and validation of the high-performance liquid chromatography (HPLC) method for the quantification of gambogic acid (GA) content in the gamboge raw sample. The chromatographic system was performed on C18 column (150 × 4.6 mm, 5 μm). The system consisted of acetonitrile and 0.1% orthophosphoric acid (85:15 v/v) as mobile phase with a flow rate of 1.5 mL/min. The detection was carried out at a wavelength of 360 nm and the retention time of GA was evident at 9 min. The method was validated according to ICH guidelines. The obtained calibration plot exhibited good linearity in the range of 5 to 120 μg/mL (r2 > 0.999). The percentage recovery GA spiked in the gamboge sample ranged from 98.87% to 102.92%. The LOD and LOQ were shown to be 2.069 and 6.271 μg/mL, respectively. The validation study demonstrated that this method was simple, specific, and applicable for quantitative analysis of GA in gamboge resin.
Wood plastic composites (WPCs) from multilayer packaging wastes and rHDPE as pallets for green industry
Authors: Boonsri T , Rukchonlatee S , Jangchud I
Published: March 2022

People are becoming more aware of plastic pollution. Consumers, researchers, and manufacturers are seeking ways to reduce their contribution to the problem. Management of plastic wastes has still been severely environmental problems, especially those with multilayer or multicomponent structures due to the difficulty in recycling process. According to the concept of circular economy, this research aimed to overcome these problems by recycling the multilayer plastic film wastes after use from consumers (classified as post-consumer recycled resin, PCR) and transforming those into high-value products. In this work, Wood Plastic Composites (WPCs) made from mixtures of multilayer packaging wastes (PCRs), recycled high density polyethylene (rHDPE) and wood powders were studied in order to be used as pallets in green industry. Studied factors affecting WPC properties included PCR types (linear low density polyethylene (LLDPE), multilayered oriented polyamide (OPA)/PE and polyethylene terephthalate (PET)/PE films) and rHDPE:PCR weight ratios (40:5, 35:10, 30:15 and 25:20). WPC samples were compounded by a two-roll mill and then shaped into samples by a compression molding machine. Morphological, mechanical and thermal properties of WPCs were examined. From SEM study, it was revealed that wood powders and fibers were well distributed and randomly oriented in WPCs. Both PCRs (OPA/PE and PET/PE) were partially melted because the processing temperatures were below the crystalline melting temperatures of OPA and PET. PCR orientation in WPCs was aligned with the compression direction. Mechanical properties of WPCs from OPA/PE were similar to those of WPCs from PET/PE. WPCs from rHDPE:PCR weight ratios of 40:5 and 35:10 had good mechanical properties which passed the industrial target values. Optimum formulas were then used to form WPC samples by extrusion technique and fabricated into WPC pallets. It was found that the WPC pallets from wastes showed promising properties with high potential to replace conventional pallets in warehouses and industrial transport for green industry.
Properties of hydroxyapatite-based geopolymer synthesized from calcined kaolin
Authors: Poolkwan K , Asavapisit S , Piyapanuwat R
Published: March 2022

This research synthesized the geopolymer from calcined kaolin (600°C for 2 h in a muffle furnace) using sodium hydroxide (NaOH) and potassium hydroxide (KOH) as alkali activators. Calcium phosphate (CP) and heat treatment were introduced to study their effects on the unconfined compressive strength (USC) and crystalline phases formation of kaolin-based geopolymer. Results showed that the highest USC strength at 28 days of geopolymer was obtained from 0.4 moles of Na2O/SiO2 and K2O/SiO2 and gave strength of 12.95 and 11.56 MPa, respectively. The USC of geopolymer was observed to decrease with the addition of CP. The amounts of 5 wt.% of CP gave a 28-day strength of kaolin-based geopolymer containing NaOH and KOH activators at 9.95 and 8.88 MPa, respectively. The CP-doped geopolymers were then heated at temperatures of 500, 600, and 700°C for 2 h Results indicated that heat treatment at 600°C gave the highest USC of CP-doped geopolymer containing NaOH and KOH equal to 7.61 and 4.61 MPa, respectively with the appearance of hydroxyapatite, muscovite, and quartz in the XRD diffractograms.
Current generation from graphene vibrations
Authors: Charoenpakdee J , Mongkolsawat T , Suntijitrungruang O , Boonchui S
Published: March 2022

The application of electrical conductivity, extremely flexible graphene membranes, to capture energy from ambient vibrations has promising potential. We study the physics of self-energy from the vibrations and how current is created in graphene for theoretical research. We demonstrate the effects of lattice distortions on the electrical current, such as isotropic tensile strain ∈is, shear strain ∈ss, uniaxial armchair strain ∈as, and zigzag strain ∈zs. We show how this movement might cause an electrical current to flow in a neighbouring circuit.
Investigation of heated silver nanowires under surface modification
Authors: Khamla T , Petchsang N
Published: March 2022

Silver nanowires (Ag NWs) have received much attention and applied in many fields due to their excellent conductivity. Hence, Ag NWs were usually integrated with low conductive materials to enhance the conductivity of the overall system. In some conditions, the surface of Ag NWs need to be modified before combining with other materials. There are many ways to change and prepare the surface of Ag NWs, for example, ligand exchange which is a simple process. TOPO (trioctylphosphine oxide) is a robust coordinating ligand and is classified as an essential component for low-dimensional nanomaterials. In comparison, ODE (1-octadecene) is a noncoordinating ligand that is often used in quantum nanomaterials preparation. In this experiment, we investigated the surface attachment for ligand exchange of TOPO and ODE on the surface of Ag NWs under variations of reaction times at 150°C. The scanning electron microscope showed the rough surface when TOPO was added, and there was no noticeable change of surface when ODE was added. These results are promising for the preparation of heterostructure in the future.