bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of Bio-jet Fuel from Palm Fatty Acid Distillate over TEOS-modified NiPd/ZSM-5 Catalysts
Authors:   , Boonsard Umbon
Published: April 2023

Jet fuels are mainly derived from the refining of petroleum feedstock which has a negative impact to the environment as it emits greenhouse gases (GHG). Therefore, the development of an alternative and renewable jet fuel is an imminent concern of the aviation industry. One of the alternative jet fuel feedstocks is palm fatty acid distillate (PFAD) due to its relatively low cost. Bio-jet fuel can be produced via three reactions including deoxygenation, isomerization, and cracking. In this study, the bimetallic NiPd supported on ZSM-5 with various Si/Al ratios (23, 50, and 280) and modified ZSM-5 by TEOS were characterized by XRD, BET, XRF, XPS, and TEM. After TEOS modification, the Si on the external surface of ZSM-5 zeolites was increased. Moreover, the TEOS-modified ZSM-5 catalyst showed similar morphological structure and bimetallic (Ni and Pd) dispersion as the unmodified catalyst. In addition, the prepared catalysts were tested in a continuous flow fixed bed reactor. NiPd/ZSM-5 (23) had high acidity, resulting in high light products. NiPd/ZSM-5 (280) exhibited a low acidity, resulting in low hydrocracking, giving high diesel product. NiPd/ZSM-5 (50) had a higher bio-jet fuel yield of 27.1% as compared to NiPd/ZSM-5 (23) and NiPd/ZSM-5 (280) (22.8% and 21.7%, respectively) due to its suitable acidity for cracking long-chain hydrocarbon into the range of bio-jet. Moreover, TEOS-modified catalyst gave higher bio-jet fuel yield with a lower light product as compared to the unmodified catalyst. Thus, TEOS-NiPd/ZSM-5 (50) exhibited the maximum bio-jet fuel yield of 44.2% with an i-/n-paraffin ratio (C₉-C₁₄) of 1.65 under the optimum reaction condition at 350 °C, 30 bar, LHSV of 1.5 h⁻¹, and H₂/feed molar ratio of 8.
Effect of dealumination and desilication of beta zeolite on performance of nickel catalysts in hydroisomerization for bio-jet fuel production
Authors:   , Hunsiri Warodom
Published: April 2023

-The Global aviation fuel consumption tends to increase. In recent years, the European Union has announced that fossil fuels jet fuel must be mixed with 10% biofuels in 2020. bio-jet fuel production has many processes such as biomass pyrolysis. or hydro-processing of vegetable oil Therefore, there is a challenge to increase the volume and specificity of bio-jet fuel. At the same time, biofuels are required properties ASTM D7566 specification. The aviation fuel has the appropriate freezing point and stability requirements to be used. This research aims to convert palm olein into bio-jet fuel by using Ni-based catalyst supported on beta zeolite with and without dealumination and desilication, which was prepared by using incipient wetness impregnation. The dealuminated beta zeolite was prepared by using HF/NH4F solution and desilicated zeolite was prepared by using NaOH solution at ambient temperature. Hydroisomerizaiton of palm olein was investigated effect of parameter: acid and base concentration (0.25-0.75 M), initial H2 pressure (30-50 bar), and reaction temperature (320-360 ˚C). The use of Ni/desilicated beta zeolite could reduce coke formation. The biofuel obtained from hydroisomerization had the high iso/normal alkane ratio at 2.54 by using Ni/beta-0.25-deA at 340 ˚C 40 under initial H2 pressure to reduce freezing point at -60.1 ˚C.
Factors predicting nutritional scores in HIV-infected elder receiving antiretroviral therapy in Thailand
Authors:   , Thet Daylia
Published: April 2023

Objectives: (1) To compare means of nutritional scores and means of depression scores from 2016 and 2020 (2) To investigate relationship between nutritional scores and depression scores (3) To establish nutritional score prediction model. Methodology: A longitudinal retrospective survey study was performed. Population were human immunodeficiency virus (HIV)-infected Thai elderly patients aged 50 years and above who were receiving HIV care and had previously participated in the aging cohort study conducted from March 2016 to April 2017 at the HIV-NAT Center, Bangkok, Thailand. Sample size for multiple regression analysis is calculated as 15 cases per 1 independent variable. This study contained 16 variables; then, 240 participants should be included. Purposive sampling method was executed. Results: A total of 250 (100%) participants were included in this study. Most of them were male (60.8%). The mean age was 59.78 ± 5.6 years. The means of nutritional scores declined in 2020 compared to 2016 (24.85 vs 25.78, p < 0.001). The mean depression scores declined in 2020 compared to 2016 (3.14 vs 3.83, p = 0.001). The participants with depression were more likely to be deteriorated in nutritional status over time than those without depression. Nutritional score prediction model confirmed by hierarchical stepwise multiple regression analysis was Nutritional scores =– 0.470 Depression scores** – 0.301 Number of medications** – 0.193 high-density lipoprotein cholesterol (HDL-C) ** + 0.126 triglyceride* + 0.105 CD4* Conclusion: Depression scores, number of medications, HDL-C, triglyceride and CD4 were significant predictors of nutritional scores.
Antioxidant and antimicrobial activities of crude extracts of actinomycetes from soils
Authors:   , Wai Khaing
Published: April 2023

A total of 17 actinomycetes isolated from soil collected from Nong Khai, Nakhon Ratchasima, Khon Kaen, Phichit, Chachoengsao and Udonthani Province, were evaluated on antimicrobial and antioxidant activities. They were identified as Streptomyces (16 strains) and Micromonospora (1 strain) based on their phenotypic and chemotaxonomic characteristics including 16S rRNA gene sequences analysis. Strain JA03 showed 98.95% similarity of 16S rRNA gene sequence to S. puniciscabiei DSM 41929T. Strain JA03 was found to be the novel species of genus Streptomyces based on whole genome average nucleotide identity (ANI).  All these strains were evaluated on antimicrobial and antioxidant activities. Based on agar disk diffusion method, strain NE2-6 closely related to Streptomyces alboniger NRRL B 1832T, has the most potent antimicrobial activity against K.rhizophila ATCC 9341 and mild activity against S.aureus ATCC 25923. ET1-12 was effective on C. albicans ATCC 10231 and on K. rhizophila ATCC 934 and on B.subtilis ATCC 6633. ET2-2 closely related to Streptomyces diastaticus subsp. ardesiacus NRRL B 1773T exhibited moderate activity against B.subtilis ATCC 6633 and K. rhizophila ATCC 9341. CT2-4 closely related to Streptomyces capoamus JCM 4734T showed moderate effect on S.aureus ATCC 25923. Strain JA03 closely related to Streptomyces puniciscabiei DSM 41929T showed the highest phenolic content (33.4 µg GAE/ mg of extract) based on TPC assay and MKP33 closely related to Micromonospora yasonensis DS 3186T showed the highest FRAP value (135 µg AAE/ mg of extract) based on FRAP assay. Strain CT1-17 closely related to Streptomyces olivaceus NRRB L 3009T, showed potent scavenging activity (80.21±0.04%) at 1,000 µg/ml with IC50 value of 218.6±27.4 µg/ml based on DPPH assay. Strain MKP33 showed more potent in nitric oxide scavenging (49.3±1.96%) at 100 µg/ml than NE2-6 (49.6±1.34%) at 500 µg/ml. Cytotoxic effects of strains NE1-12, ET3-23, CT1-17, NE2-6, CT2-4, CT2-10, JA03 and MKP33 on RAW264.7 macrophage cells were evaluated by % cell viability.  Strains NE1-12, CT1-17, JA03 and MKP33 showed no cytotoxic effect at 200µg/mL and strains CT2-4, CT2-10, ET3-23 and NE2-6 at 10 µg/ml on RAW 264.7 macrophage cells. Strain ET3-23 inhibited intracellular ROS generation (33±6.56%) in H2O2 (100µM) induced RAW 264.7 cells. CT2-10 at 10 µg/mL significantly inhibited NO production induced by LPS (100ng/ml) in RAW264.7 macrophage cells when compared with MKP33 at 200 µg/ml (13.87± 1.78µM and 2.9±1.02µM, respectively). In conclusion, these findings confirmed that Strain JA03 is the novel species of genus Streptomyces and possesses antioxidant activity.  The actinomycetes isolated from soil provided the activity information in the development of good candidates for antibiotics and antioxidants.
Anti-migratory and anti-invasive activities of 22-o-(n-Boc-l-glycine) ester of renieramycin m against human lung cancer h460 cells
Authors:   , Oo Yamin
Published: April 2023

The incidence of metastasis stage crucially contributes to high recurrence and mortality rate in lung cancer patients. Unfortunately, no available treatment inhibits migration, a key metastasis process in lung cancer. In this study, the effect of 22-O-(N-Boc-L-glycine) ester of renieramycin M (22-Boc-Gly-RM), a semi-synthetic amino ester derivative of bistetrahydroisoquinolinequinone alkaloid isolated from Xestospongia sp., on migratory behavior of human lung cancer cells was investigated. Following 24 h of treatment, 22-Boc-Gly-RM at non-toxic concentrations (0.5-1 µM) effectively restrained motility of human lung cancer H460 cells assessed through wound healing, transwell migration and multicellular spheroid models. The capability to invade through matrix component was also repressed in H460 cells cultured with 0.1-1 µM 22-Boc-Gly-RM. The dose-dependent reduction of phalloidin-stained actin stress fibers corresponded with the down-regulated Rac1-GTP level presented via western blot analysis in 22-Boc-Gly-RM-treated cells. Treatment with 0.1-1 µM of 22-Boc-Gly-RM obviously caused suppression of p-FAK/p-Akt signal and consequent inhibition of epithelial to mesenchymal transition (EMT), which was evidenced with augmented level of E-cadherin and reduction of N-cadherin expression. The alteration of invasion-related proteins in 22-Boc-Gly-RM-treated H460 cells was indicated by the diminution of matrix metalloproteinases (MT1-MMP, MMP-2, MMP-7 and MMP-9) as well as the up-regulation of tissue inhibitors of metalloproteinases (TIMP), TIMP2 and TIMP3. Thus, 22-Boc-Gly-RM is a promising candidate for anti-metastasis treatment in lung cancer through inhibition of migratory features associated with suppression on EMT.
Development of hyaluronic acid-based nanogel platform for improved stability and polyvalent ligand display of poly(I:C) as an effective immunostimulatory adjuvant in cancer immunotherapy
Authors:   , Kotcharat Nararat
Published: April 2023

The aim of this research was to develop a nanogel formulation-based on modified natural polymer, hyaluronic acid (HA), as a biodegradable material for adjuvant delivery. Polyinosinic:polycytidylic acid (poly(I:C)) have been approved by FDA as a promising adjuvant candidate for the TLR3 (Toll-Like Receptor 3) activation. However, it suffers from being poor stability and is subjected to rapid enzymatic hydrolysis in serum, so that it requires high administered dose leading to adverse effects. To augment the adjuvant stability and protection from the degradation, the nano-particulate carriers were herein designed with self-assembly of HA scaffold grafted with poly (N-isopropylacrylamide), or pNIPAM. The grafting was processed through amide formation using the coupling agent (EDC/NHS). 1H NMR was carried out to confirm the modified products (HA-g-pNI). The physical incorporation of the nucleic acid into the grafted HA nanogel was achieved by incubation method with the poly(I:C) concentrations of 0.2, 1, and 10 (μg/mL) in formulations by using 0.1, 0.25, and 0.5 (% w/v) of HA-g-pNI to form the nanogel particles. The mean size, size distribution and surface charge of the nanogel particles were determined by dynamic light scattering (DLS). The particle morphology was investigated by transmission electron microscopy (TEM). Results demonstrated that HA-g-pNI with a 4 % degree of substitution were formed into nearly spherical nanogel particles with the size of approximately submicron range. The particles presented a negative value in zeta-potential. Moreover, we founded that the average size and polydispersity index (PDI) of the loaded particles were decreased significantly upon continuous incubation showing that poly(I:C) was entrapped. The stability against fetal bovine serum (FBS) degradation of the poly(I:C)-loaded nanogels was demonstrated by gel electrophoresis. Furthermore, cell viability of all HA-g-pNI formulations showed more than 80% of cell viability via RAW 264.7 macrophages. The poy(I:C)-loaded nanogel particles were excellent internalized by RAW 264.7 macrophages after 24 hrs of incubation. Therefore, the development of these poly(I:C)-loaded grafted HA nanogels will lead to a new generation of smart materials that can be functionalized and optimized for different medical purposes.
Development of recombinant human epidermal growth factor production in Nicotiana benthamiana
Authors:   , Hanittinan Oranicha
Published: April 2023

Human epidermal growth factor (hEGF) is a short polypeptide that has gained clinical importance in the recent decade for wound healing. Currently, plant-based expression system is considered as an alternative viable platform for low-cost recombinant protein production. Hence, this study aims to produce hEGF in Nicotiana benthamiana plants via., transient expression using a geminiviral vector. The hEGF gene constructs were designed into six different constructs. The optimal expression was observed from the construct targeting the endoplasmic reticulum with C-terminal histidine tag at the yield level up to 15.695 µg/g LFW or 0.499% TSP. The plant-produced hEGF was purified by using Nickel affinity chromatography and confirmed its identity by SDS-PAGE and Western blot probed with anti-hEGF antibody. Furthermore, the preliminary study of the protein purification efficiency was found that the high extraction volume allows better hEGF recovery and extraction buffer pH 4 could largely remove host cell proteins (HCP), especially RuBisCO. However, ammonium sulfate precipitation is inapplicable for removing HCP from plant-produced hEGF.  Furthermore, the study showed that no cytotoxic effects have been found in HaCaT cells from the plant-produced hEGF which is equivalent to commercial hEGF in HaCaT cells. Hence, this study supports that the potential of plant expression system offers a simple and cost-effective approach for the industrial-scale production of recombinant hEGF.
Production of recombinant protein ltb-ctla4 by transient plant-based expression using geminiviral vector
Authors:   , Yiemchavee Sutita
Published: April 2023

Cancer is one of the leading global causes of death. In 2018, WHO estimated that 9.6 million patients died from cancer, with 18.1 million new cases emerged. In recent years, immunotherapy is considered as a treatment improving cancer-related immune function by manipulating the immune checkpoints in the immune system. Cytotoxic-T-lymphocyte antigen 4 (CTLA-4) is a immune checkpoint transmembrane protein. The expression of CTLA-4 on the surface of activated T-cell could downregulate the production and proliferation of cytotoxic T-lymphocyte cells (CTLs). CTLs are the host-defended immune cells that could retard the growth of cancer cells by recognizing the tumor-associated antigens expressed on the membrane of cancer cells, then eliminate them before spreading and evading throughout the body. The overexpression of CTLA-4 founded in cancer has a suppressive effect on cytotoxic T-lymphocyte cells, encouraging the tumor cell's growth. Recently, the monoclonal antibodies targeting CTLA-4 have successfully proved to be an active agent in immunotherapy. However, the large amount and multiple dosing had been a major hindrance. In this study, we developed heat-labile enterotoxin B subunit (LTB) fused CTLA-4 or LTB-CTLA4 as a cancer vaccine, to reduce the disadvantage in term of quantity, price, and frequency of dosing. LTB-CTLA4 was produced in Nicotiana benthamiana plant as a bio-factory, a promising platform for the plant-derived biopharmaceutical production which has abilities to produce high value but cost-effective vaccines. The highest LTB-CTLA4 level reached 1.29 µg per gram plant fresh weight and induced BALB/c mice to produce specific IgG against CTLA-4. LTB-CTLA4 has a potential as a candidate agent for cancer vaccine either to prevent the development of cancer or to treat cancer in the future.
Anticancer activity of cepharanthine on non-small cell lung cancer cells
Authors:   , Detpichai Yaowaluck
Published: April 2023

Cepharanthine (CEP) is a biscoclaurine alkaloid, isolated from the roots of Stephania cepharanthine Hayata that possesses potent anticancer properties against several types of cancer such as hepatocellular carcinoma, colorectal cancer, leukemia and ovarian cancer. However, there is still limited information regarding to its effects on non-small cell lung cancer cells. Therefore, the objectives of the present study were to determine the cytotoxicity of CEP and its underlying mechanisms in non-small cell lung cancer cells expressing wild-type p53 and EGFR (A549) and non-small cell lung cancer cells expressing mutant p53 and EGFR (H1975). The results indicated that CEP significantly inhibited the viability of A549 and H1975 cells in a concentration-dependent manner, with the inhibitory concentration at 50% cell growth (IC50) values of 4.31±0.52 and 11.81±2.07 µM, respectively. Moreover, apoptosis-inducing effect of CEP were detected in both A549 and H1975 cells. Western blot results demonstrated that CEP could upregulate Bax and Bak as well as downregulate of Bcl-2 and Bcl-XL in A549 cells and downregulate Bcl-2 in H1975 cells. Also, CEP was able to induce the cleavage of poly-(ADP-ribose) poly­merase (PARP) in both A549 and H1975 cells. It should be noted that apoptosis-inducing effect of CEP were diminished when the cells were pretreated with N-acetylcysteine (NAC), a ROS scavenger, suggesting that CEP-induced apoptosis was mediated through ROS generation. In addition, CEP inhibited ERK signaling pathway in A549 cells but activated ERK signaling pathway in H1975 cells. Moreover, CEP could inhibit STAT3 and Akt signaling pathways in both NSCLC cell lines. Remarkably, NAC could prevent CEP-mediated inhibition of STAT3 in both A549 and H1975 cells and CEP-mediated Akt inhibition in H1975 cells, indicating that ROS is involved in the inhibitory effects of CEP on STAT3 and Akt signaling pathways. Taken together, these results suggest that CEP exhibited potent cytotoxicity through induction of apoptosis, generation of ROS and modulation of STAT3, PI3K/Akt and MAPK/ERK signaling pathways in NSCLC cells. Our findings demonstrated that CEP may have a potential to be develop as a novel anticancer drug for lung cancer.
Pharmacokinetic and metabolomic studies of standardized extract of centella asiatica (ECa 233) capsule in Thai healthy volunteers
Authors:   , Songvut Phanit
Published: April 2023

A well-characterized standardized extract of Centella asiatica (ECa 233) being developed as a phytopharmaceutical product for human use was explored in this clinical study. The first objective of this research was to understand changes in disposition kinetics after oral administration of both the original-formula capsule and a newly-modified enhanced-dissolution capsule of ECa 233. Secondly, this study aimed to investigate alteration of human metabolomes following administration of the modified capsule of ECa 233, using an NMR-based metabolomics approach. For pharmacokinetics, the study involved a phase I clinical trial in twelve healthy Thai volunteers, who each received 250 and 500 mg of the original ECa 233 capsule and of the modified ECa 233 capsule, first as a single dose and then a week later as once-daily doses for 7 consecutive days. The results demonstrated that two major parent compounds, madecassoside (MDS) and asiaticoside (ASS), were rarely absorbed but rather underwent extensive biotransformation with minimal renal excretion. Those unabsorbed parent compounds were substituted with two mainly-active metabolites, madecassic acid (MDA) and asiatic acid (ASA). These metabolites were likely excreted through hepatobiliary system by feces elimination. Interestingly, increasing the dose of ECa 233 resulted in significantly greater plasma levels of these active metabolites, with accumulation of asiatic acid after multiple oral administration. Considering metabolomics, this accumulation behavior could affect human metabolome, partly through an alteration between pre- and post-dose of endogenous metabolites detected in plasma. The changes in five relevant metabolites were thoroughly considered to identify candidate biomarkers; these were L-homoserine, citrulline, O-succinyl L-homoserine, homocarnosine, and choline. In particular, ECa 233 was associated with a significant increase in levels of choline, an endogenous metabolite reported to have benefits for learning and memory. This finding suggests that ECa 233 may adjust human metabolic profiles and in this way play a role in fulfilling endogenous metabolites, which might be useful in mitigating cognitive impairment in phase II clinical study.
Development of a device to alert for breaks to prevent musculoskeletal disorders in the neck and low back among office workers
Authors:   , Waongenngarm Pooriput
Published: April 2023

The objective of this thesis was to develop a device to alert for breaks to prevent musculoskeletal disorders in the neck and low back among office workers. This thesis was divided into four stages: 1) systematically review to gain insights into the effectiveness of breaks on low back pain, discomfort, and work productivity in office workers; 2) evaluation of the characteristics of perceived discomfort and postural shifts during a 4-hour sitting period; 3) evaluation of the effects of a device to alert for active breaks on preventing neck and low back pain among office workers: 6- and 12-month follow-up; and 4) evaluation of the incidences of neck and low back pain and working from home related risk factors during the COVID-19 outbreak among office workers. The results from systematic review revealed that breaks are recommended for reducing low back pain and discomfort with no disturbance in work productivity among office workers. The type of rest breaks that may be effective in reducing low back pain and discomfort was identified, namely active breaks with postural change. In the second study, our findings suggest that prolonged sitting for longer than 30 minutes possibly increase the risk of neck and low back pain, which used to develop the device to alert for breaks. The device to alert for break was developed by the author and engineering team, which consists of three components: seat pad, controller and smartphone application. This device can detect sitting time and recommend break duration during work to the user. The device had good to excellent validity and consistency. The results of the effectiveness of the device on preventing neck and low back pain showed that office workers who received the device to alert for breaks significantly reduced the 6- and 12-month incidence rate of neck and low back pain. In addition, the incidence of neck and low back pain during the COVID-19 period was lower than that for during the pre-COVID-19 period. The number of days working from home per week was associated with the incidence of neck and low back pain during COVID-19 period.
The wormholes in the modification of general relativity theory
Authors:   , Tangphati Takol
Published: April 2023

A traversable wormhole, which is a class of wormholes in general relativity (GR), was proposed by Morris and Thorne in 1988. However, its existence requires the exotic matter violating the energy conditions. This thesis examines the wormhole solutions in the theory of massive gravity, focusing only on the de Rham, Gabadadze and Tolley (dRGT) theory of massive gravity which is the nonlinear massive gravity without ghost and quantify the wormhole solutions. We construct the wormhole solutions in context of the modified GR, investigate their stability, and examine the conditions of the exotic matter. Two methods for wormhole constructions are applied i.e., the Lorentzian traversable and thin-shell wormholes. We found that the wormholes in dRGT massive gravity require the exotic matter only near their throats not spreading all the Universe like in GR.
Fabrication and characterization of graphene-based heterostructure using molybdenum as alternative electrodes
Authors:   , Klanurak Illias
Published: April 2023

Interlayer coupling in graphene heterostructures can be used to modify their charge transport properties for the use in nanoelectronics applications. To achieve high-performance devices, graphene is typically encapsulated by two thin sheets of hexagonal boron nitride (hBN) and contacted using Cr/Au as electrodes. ​ In this research, Mo was selected as alternative stand-alone electrodes to simplify the fabrication process. We have developed a recipe for the fabrication of field-effect transistor (FET) using twisted bilayer graphene (tBLG) as a transport channel. Mo was employed to make one-dimensional (1D) contacts to the edges of graphene by sputtering. Electronic transport measurement was then performed on the FET devices to investigate the quality of Mo contacts. We achieved ohmic contacts between Mo and graphene. The contact resistivity between Mo and graphene reached a maximum value of around 1,300 Ω⋅µm at charge neutrality point and decreased to 975 Ω⋅µm at a carrier density of ~4×1012 cm-2. However, we have observed that the contact resistivity increases over time likely due to the oxidization of Mo. Despite the increase in contact resistivity, the Mo contacts still exhibit ohmic behavior after 3 months and it can be used to investigate transport phenomena in graphene. In this study, the room-temperature electron and hole mobilities of tBLG reached values as high as 27,000 and 21,000 cm2/V⋅s indicating that Mo electrodes do not hinder the transport characteristics of graphene.
Holographic solutions from N=6, D=4 gauged supergravity
Authors:   , Seeyangnok Jakkapat
Published: April 2023

In this thesis, we study holographic solutions of four-dimensional N = 6 gauged supergravity with SO(6) gauge group. The theory admits a unique N = 6 supersymmetric AdS4 vacuum dual to a three-dimensional N = 6 SCFT and gives us a number of supersymmetric domain walls interpolating between this AdS4 vacuum and singular geometries in IR with SO(2) × SO(4), U(3), SO(2) × SO(2) × SO(2), and SO(3) symmetries. These solutions describe RG flows from N = 6 SCFT in UV to non-conformal field theories driven by mass deformations. In particular, the solution with SO(2)×SO(4) symmetry coincides with the known mass deformations of the dual N = 6 SCFT. Despite most of the solutions preserving N = 6 supersymmetry, the SO(3) case preserves N = 6 or N = 2 depending on the absence of pseudoscalars. We also give an analytic form of supersymmetric Janus solution with SO(2)×SO(4) symmetry, which describes a two-dimensional conformal defect in the N = 6 SCFT with unbroken N = (4, 2) supersymmetry. Finally, we study supersymmetric AdS black hole with magnetic charges and the horizon geometry of the form AdS2 × H2. We find an N=2 supersymmetric solution with SO(2)×SO(4) symmetry interpolating between the AdS4 vacuum and an AdS2 ×H2 fixed point, which is dual to a twisted compactification of N = 6 SCFT on hyperbolic space H2.
Intermodulation distortions from a chain of coupled nonlinear oscillators near a hopf bifurcation
Authors:   , Thipmaungprom Yanathip
Published: April 2023

The inner ear can produce sounds whose frequencies correspond to linear combinations of the stimulus frequencies, f1 and f2. These sounds, called Distortion Product Otoacoustic Emissions (DPOAEs), can be measured by inserting a microphone into the ear canal. In human, the intensity level of DPOAEs at frequency 2f1-f2 varies significantly with a stimulus frequency and can exhibit a quasi-periodic pattern, a feature termed a DPOAE fine structure. This distinctive characteristic has been generally accepted as a consequence of the interference between two DPOAE signals produced by two spatially separated groups of sensory hair cells, whose characteristic frequencies correspond to the stimulus frequencies, and the distortion frequency. However, a recent study revealed that a similar feature can be observed from Chinese edible frogs, whose inner ear structure does not support the two-signal interference hypothesis as in vivo amphibian hair cells are strongly coupled. In this work, we performed numerical simulations of nonlinear distortions produced by a chain of strongly coupled nonlinear oscillators, a structure that represents hair cells in a simple inner ear. Our results revealed that the amplitude of the total distortion from the oscillators, arranged in order of their characteristic frequencies, can display a quasiperiodic variation pattern under appropriate driving forces levels. Analyses of the motion of individual oscillators showed that those with low characteristic frequencies underwent a standing wave at the distortion frequency, a feature that was responsible for the quasiperiodic pattern. On the other hand, coupling between oscillators arranged in a random order of characteristic frequencies yielded a nonlinear response resembling that of a single oscillator. Results from the model agreed qualitatively with prior experimental observations. Our results thus suggest multiple mechanisms underlying DPOAEs produced by the frog’s ear, governed by the arrangement of the sensory cells.
Comparative study of tensile bond strength between resin cements and hybrid materials
Authors:   , Donpinprai Chakriya
Published: April 2023

Purpose: To compare tensile bond strength among the hybrid materials (VITA ENAMIC®, SHOFU Block HC, Katana AVENCIA and Experimental material) using two primers (Universal ceramic primer and RelyX ceramic primer) and two resin cements (Super-Bond C&B and RelyXTM U200). Methods: Twenty blocks of 4×4×1 mm3 were prepared from each material type. In VITA ENAMIC® group, specimens were conditioned with 5% Hydrofluoric acid and primer. In SHOFU Block HC and Katana AVENCIA groups, specimens were treated with 50µm alumina and primer. In experimental material, specimens were etched with 65% Phosphoric acid. Ten specimens were randomly assigned to each group for different resin cement then cemented on bovine enamel. All cemented specimens were stored in water at 37ºC for 24 hours. TBS was tested with a universal testing machine. The fractured interface was examined with a stereomicroscope and TBS data were statistically analyzed. Result: The experimental material showed the highest TBS values, followed by VITA ENAMIC®, Katana AVENCIA, and SHOFU Block HC, respectively. There was no significant difference between different resin cement (p>0.05). In SHOFU Block HC group, all fractured specimens showed adhesive failure. Conclusion: The types of inorganic components and surface treatment of the hybrid materials have an effect on TBS values.
Effect of ultrasonic treatment on the transverse strength of relined denture base with autopolymerizing acrylic hard reline material
Authors:   , Arunwichit Tithiporn
Published: April 2023

This study evaluated the effect of ultrasonic treatment and surface treatments on transverse strength of denture bases which relined with auto-polymerizing acrylic resin. The study groups, ninety heat-polymerized acrylic resins (64×10×2 mm) were divided by three surface treatments: no surface treatment (N), applied MMA for 180 seconds (MM), applied MF-MA for 15 seconds (MF). They were relined with auto-polymerized acrylic resin to create 64×10×3.3 mm specimens. Then, they were divided further by ultrasonic which were no ultrasonic (X), ultrasonic in water (W), ultrasonic in 30% ethanol (E). As a result, all test groups were classified as NX, NW, NE, MMX, MMW, MME, MFX, MFW, MFE (n=10). All samples were performed three-point bending test. Two-way ANOVA presented that there was an interaction between ultrasonic and surface treatments. Then One-way ANOVA was analyzed. Ultrasonic could increase transverse strength of all relined specimens (p<0.05). Ultrasonic in ethanol increased strength superior to water (p<0.05) and presented the highest mean strength. In the same ultrasonic treatment, MMA and MF-MA increased the transverse strength of relined denture bases compared with no applying groups (N) (p<0.05). There was no difference between all MM and MF groups (p>0.05).
Gene expression and immunohistochemistry analysis of xenograft and allograft in maxillary sinus floor augmentation
Authors:   , Kungvarnchaikul Isaya
Published: April 2023

Quality of bone is an important factor contributing to the success of dental implants. The bone height in maxillary posterior area sometimes is not enough and might pose risks for placing dental implants. Maxillary sinus augmentation with bone substitutes is used for filling and correcting bony defects. This study aims to determine the differences in gene expressions of TNF-alpha, RUNX2, COL1A1, ALP between xenograft (Bio-Oss®) and allograft (SureOss®). Patients who needed two-stage maxillary sinus floor augmentation were included (n=13). Patient who had dental implant at posterior maxilla without bone substitutes was also used in immunohistochemistry analysis (IHC) (n=1). Bone samples were collected using trephine bur 2 mm internal diameter. Quantitative real-time PCR (qPCR) method was used for studying gene expression (n=10). Immunohistochemical staining of ALP was used to visualize the area of osteogenic activity (n= 4). The results of qPCR showed higher RUNX2 expression of allograft when compared to xenograft (p<0.05). Although, TNF-alpha, COL1A1 expression was not statistically different between groups. Immunohistochemistry staining of both samples also showed similar intensity and expression of ALP. The data suggested that gene expression levels of TNF-alpha and COL1A1 were not significantly different between bone grafted with Bio-Oss® and SureOss®. However, the expression of RUNX2 was significantly higher in SureOss®. Nevertheless, result from IHC study showed similar characteristics between both groups.
Influence of demineralized dentin on marginal seal using primerless wet bonding technique: in-vivo study
Authors:   , Lerttriphob Thanyarat
Published: April 2023

The purpose of this study was to compare microleakage distance between Class V restorations and tooth interface when using either 4-META-MMA/TBB or MMA/TBB resin adhesives by using 1 % ferric chloride in 1% citric acid (1-1) for conditioning periods of 10s (1-1-10s) 30s (1-1-30s) and 60s (1-1-60s) for in-vivo study. Material and methods: A total of 60 Class V box cavities were divided into 6 groups of 10 specimens (n= 10) on the caries-free, vital, and hopeless periodontally-compromised teeth, scheduled for extraction. A Class V cavity (3mm × 3mm × 1.5mm) was prepared on the buccal or lingual surface located at the cemento-enamel junction of each tooth providing margins in enamel and cementum/dentin. All cavities were conditioned with 1-1 aqueous conditioner for 10 s, 30s or 60s each group, rinsed off with water for 10 s, blot-dried for 10s and bonded with different resin adhesives (4-META/MMA-TBB or MMA-TBB) before coupled with light-cured resin composite. Restored teeth continued under function in oral cavity for 7 days before extraction. After extraction, all specimens were coated with nail varnish, except for restorations and 1 mm away from occlusal and cervical margins, then immersed in 0.5 % basic fuchsin dye solution for 24 h. All specimens were vertically sectioned. The margin and distance of dye penetration was investigated by a stereomicroscope. Results: There is no leakage at the tooth-resin interface at enamel and cementum/dentin margins either using 4META-MMA/TBB or MMA/TBB resin for all etching periods. Only 1 specimen of 60s etching and bonding with MMA/TBB resin has leakage distance at cementum/dentin margin of 0.13 mm. Conclusion: Impermeable hybridized interfaces were formed in all groups with 4META- MMA/TBB or MMA/TBB resin using (1-1) to condition tooth surface for 10-60 seconds. No leakage along tooth-adhesive interface was found in clinically. This suggests the ability of leakage prevention which help prevent tooth sensitivity, caries under the restorations and/or infection in the pulpal cavity predicting the long-term success of restored teeth.
Cost effectiveness of oral health care program implementation in primary school in Bangkok, Thailand
Authors:   , Luksamijarulkul Nicha
Published: April 2023

Dental caries are common oral diseases in schoolchildren. This retrospective cohort analysis was done to assess caries prevalence, risk and protective factors associated permanent caries among 433 children profiles of school children in selected primary school in Bangkok who received or did not receive a preventive program. Additionally, a cost effectiveness of the program was analyzed. Result revealed that there was high caries prevalence in deciduous teeth (1st grade) 87.2% and mean dmft 6.44 (± 4.4) and caries prevalence in permanent teeth (6th grade) 51.7% and mean DMFT 1.37 (± 1.84). Risk and protective factors associated permanent caries, after logistic regression analysis found only deciduous caries was a significant risk factor associated with caries in permanent teeth (Adj OR=5.44, 95% of CI = 2.23-13.27). Sealant coverage all 1st molars was a significantly protective factor associated with caries in permanent teeth (Adj OR=0.19, 95% of CI = 0.06-0.63). It indicated that early detection and prevention program should be provided for this group of children.

The total estimated costs of school oral health program (SOHP) in provider perspective, was 1,196,839.37 Baht in economic cost. Salaries of supervisor, costs of equipment and material for sealant, PRR and filling were a majority part of labor costs, capital costs and material costs, respectively. Particularly, in capital cost and material costs were accountable for more than half of total costs. Average capitation of SOHP was equal to 2,045.88 baht per child per year. ICER between completed SOHP and examination group was 2,961.47 baht per DMFT avoided.
Improving Routine Immunization coverage through strengthening Interpersonal Comminication skills of primary health care workers in rural Local government areas in kebbi state Nigeria
Authors:   , Basheer Saudat
Published: April 2023

Background: In 2015, Kebbi state was among the four (4) states in northwestern Nigeria that have low routine immunization performance in the country. National Nutrition and Health Survey 2015 report indicated that only 7.8% of the eligible children have received three doses of DPT/Penta and measles coverage was 14.7%. There was no documented research to investigate the effect of interpersonal communication skills on routine immunization services in Kebbi state Nigeria. The objective of this study, therefore, was to examine the effect of vaccination education on improving mothers’ knowledge and uptake of routine immunization services among children in the rural LGAs of Kebbi State. Methods: The study was a quasi-experimental one was conducted in two Local Government Areas (LGAs) in Kebbi State, between October 2016 to March 2017. Health Education Officers and Primary Health Care workers trained from the intervention centers were trained on interpersonal communication skills. Data were collected using a questionnaire on the vaccination status of the children after intervention from children’s vaccination cards and mother’s verbal reports. The knowledge, attitude, and practice of mothers were also analyzed. Descriptive statistics, Chi-square, and student t-test were used to test the effect of the intervention on knowledge, attitude and practice, and immunization coverage between the control group and intervention group. Results: There was a significant difference in the mean scores for knowledge at baseline in the intervention group (M =2.01, SD = 2.99) compared with mean knowledge at the end line (M = 5.42, SD = 3.35). The mean difference of 3.40 between baseline and end-line indicated that knowledge of mothers/caregivers on routine immunization has increased after the intervention. 53.8% of children in the intervention group were fully immunized while in the control it was 9.5% increasing only by about 2%. The percentage of unimmunized children was high in both groups at pre-intervention (66%) but this decreased to 29.5% in the intervention group and 57.6% in the control group. There was a statistically significant difference of change of attitude between intervention and control group after intervention with p=<0.001. Conclusion: The results of this study suggest that the use of IPC skills intervention could improve Knowledge, Attitude, and Practice consequently improving routine immunization. Such improvement could translate into better immunization performance.
A Social Ecology of Sexual Health and Well-being among Older Gay Men and Transgender Women in Chiang Mai, Thailand: A Qualitative Study
Authors:   , Tepjan Suchon
Published: April 2023

With increasing ageing populations in Thailand, including sexually diverse communities, there has been little attention to older gay men and transgender women regarding their sexual health and well-being. Several international studies indicated that these communities have been underserved, especially in countries that lack human rights to protect against social and cultural stigma. The well-being of this population, that had experienced discrimination, victimization, and identity concealment in their early years, could have been better understood through open-ended exploration. This study explores the social-ecological factors contributing to the sexual health of older gay men and transgender women in Chiang Mai. This qualitative study was guided by a grounded theory approach. Eighteen in-depth interviews were conducted in Thai with 9 older gay men and 9 older transgender women aged 60 years and older and were locals. The semi-structured interview guide was informed by the social-ecological model. The interviews were digitally recorded and transcribed. The researcher conducted thematic analysis using line-by-line and thematic coding from the transcripts. Several themes emerged from the interviews across the social-ecological model–individual level: embarrassment of ageing, feeling of loneliness; interpersonal level: isolation, friends and family support; sociocultural level: culture and beliefs, stigma and discrimination; structural level: social exclusion, discrimination and stigmatization from service providers, and lack of law supporting ageing sexual minority populations. The intersectional impact of multi-level factors on sexual health and well-being of older gay men and transgender women demonstrated that individual- and interpersonal-level experiences could contribute to their well-being, both physically and mentally. Interventions on acknowledging awareness and the health needs of such marginalized communities may support understanding and improvement of their health quality. Sociocultural- and structural-level factors suggest that further social policy and intervention research should promote inclusion and equality for older gay men and transgender women in Thailand.
Association between factors related and stress, depression and suicidal risk among health care personnel during covid-19 second outbreak in Thailand
Authors:   , Polrak Aphichaya
Published: April 2023

Health care personnel are one of most affected by COVID-19 situation. The aim of this study was to identify the prevalence of stress, depression and suicidal risk and associated factors among health care personnel during COVID-19 second outbreak in Thailand. This study was cross-sectional study, which used secondary data collected during December 17, 2020 to February 23, 2021. Total of 4,970 health care personnel participated in this research. The instruments of this research were ST-5, 9Q and 8Q. Multivariable logistic regression analysis was performed to identify factors associated with stress, depression and suicidal risk outcomes. The prevalence of stress, depression and suicidal risk in this study was 6.2%, 9.1% and 2.5% respectively. In multivariable logistic regression analysis showed that stress were significantly associated with participants who live in zone 5 (Bangkok Province) [AdjOR=2.00, 95%CI(1.30-3.07)],  who was risk group of burnout [AdjOR=22.34, 95%CI(16.52-30.22)] and who had low-moderate resilient quotient [AdjOR=14.28, 95%CI(8.56-23.81) and AdjOR=3.96, 95%CI(2.76-5.68)]. Depression was significantly associated with participants who live in zone 5 (Bangkok Province) [AdjOR=1.80, 95%CI(1.25-2.59)],  who were risk group of burnout [AdjOR=10.86, 95%CI(8.53-13.83)] and who had low-moderate resilient quotient [AdjOR=22.41, 95%CI(14.54-34.53) and AdjOR=4.95, 95%CI(3.74-6.54)]. Suiciadal risk was significantly associated with participants who live in zone 5 (Bangkok Province) [AdjOR=2.80, 95%CI(1.43-5.50)],  who were risk group of burnout [AdjOR=7.14, 95%CI(4.66-10.92)] and who had low-moderate resilient quotient[AdjOR=34.07, 95%CI(16.66-69.68) and AdjOR=5.74, 95%CI(3.01-10.95)]. That showed implication of this study reveals  that in addition to internal factors and external factors as well.
Factors associated with knowledge and awareness of syphilis among the youths visiting family planning clinics, Bangkok, Thailand
Authors:   , Tattanon Nutcha
Published: April 2023

Syphilis has been controlled since 1960. However, syphilis is now reappearing in some areas in Africa and South-east Asia including Thailand. In Thailand, syphilis is reappearing in all regions. The most high-risk population is the youth aged 15-24 year. Objective of this study aimed to determine factors associated with knowledge and awareness of syphilis prevention among youths visiting at family planning clinic, Bangkok, Thailand. Method of this study was a cross-sectional study conducted by purposive sampling among the youth aged 15-24 years old who visit at PPAT family planning clinic, Bangkok, Thailand during April-June 2021. Multivariable logistic regression analysis was used to determine the association between factors and the knowledge/awareness level of syphilis prevention. Total 207 participants were recruited in this study. The result from multivariable logistic regression analysis showed that unemployment associated with lower knowledge level compared with fulltime job [OR 0.29, 95% CI (0.11-0.75)], living with family or relative associated with lower knowledge level compared with living alone [OR 0.187, 95% CI (0.07—0.51)], always use of condom associate with higher knowledge level compared with never use condom [OR 7.95, 95% CI (1.64-38.61)], participant who never had a reproductive health education associated with lower knowledge level compared with participant who had a reproductive health education [OR 0.29, 95% CI (0.11-0.77)], and participant who had ever used a reproductive health service at private clinic/hospital associated with lower knowledge level compared with who use this service for the first time [OR 0.27, 95% CI (0.07-0.99)]. According to the awareness, participant who had a good knowledge level associated with higher awareness level of syphilis prevention compared with those who had fair or poor knowledge level [OR 1.19, 95% CI (1.06-1.33)]. We concluded that the youths were recognized as vulnerable group for syphilis. To prevent them, it was important for public health to emphasize on knowledge and awareness regarding syphilis prevention among the youths. Additionally, novel strategy to increased knowledge and awareness level of syphilis prevention need to be considered.