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Papers by Thiên Vui Nguyễn

Tạp chí Y Dược học Cần Thơ, Sep 20, 2022

thuốc chống chỉ định chiếm tỷ lệ 7,8% và tương tác thuốc nghiêm trọng chiếm tỷ lệ 24,3% trong đơn... more thuốc chống chỉ định chiếm tỷ lệ 7,8% và tương tác thuốc nghiêm trọng chiếm tỷ lệ 24,3% trong đơn thuốc điều trị ngoại trú. Tương tác thuốc chống chỉ định chiếm tỷ lệ 5,8% và tương tác thuốc nghiêm trọng chiếm tỷ lệ 11% trong hồ sơ bệnh án điều trị nội trú. Có mối liên quan giữa độ tuổi của bệnh nhân, số lượng thuốc sử dụng trong đơn thuốc và khả năng xảy ra tương tác thuốc có ý nghĩa thống kê (p<0,05). Kết luận: Độ tuổi của bệnh nhân càng cao, số lượng thuốc sử dụng càng nhiều thì nguy cơ xảy ra tương tác thuốc càng cao. Cần sàng lọc tương tác thuốc bất lợi thường xuyên để đảm bảo an toàn cho bệnh nhân và tránh các tác dụng không mong muốn. Từ khóa: Phối hợp thuốc, tương tác thuốc, đơn thuốc, bệnh án.

JMIR Formative Research, 2021

Background Medication nonadherence is a global public health challenge that results in suboptimal... more Background Medication nonadherence is a global public health challenge that results in suboptimal health outcomes and increases health care costs. Forgetting to take medicines is one of the most common reasons for unintentional medication nonadherence. Research findings indicate that voice-activated virtual home assistants, such as Amazon Echo and Google Home devices, may be useful in promoting medication adherence. Objective This study aims to create a medication adherence app (skill), MedBuddy, for Amazon Echo devices and measure the use, usability, and usefulness of this medication-taking reminder skill. Methods A single-group, mixed methods, cohort feasibility study was conducted with women who took oral contraceptives (N=25). Participants were undergraduate students (age: mean 21.8 years, SD 6.2) at an urban university in the Southeast United States. Participants were given an Amazon Echo Dot with MedBuddy—a new medication reminder skill for Echo devices created by our team—att...

JMIR Formative Research, 2022

International Journal of Environmental Research and Public Health, 2021

Aim: Describe virtual home assistant use and usefulness from the perspective of older adults and ... more Aim: Describe virtual home assistant use and usefulness from the perspective of older adults and their support persons. Methods: This was a mixed-methods study with older adults and their support persons (n = 10 dyads). Virtual home assistant (VHA) equipment was installed in participants’ homes, and its use was documented for 60 days. Participants received protocol-guided telephone calls to address their VHA questions or problems. The type and frequency of VHA use were summarized with descriptive statistics. End-of-study interviews about VHA use were conducted with dyad participants. Qualitative content analyses were used to describe the interview findings about the dyad’s perceptions of using the VHA, how it was used, any difficulties experienced, and suggestions for future VHA uses. Results: Participant dyads reported positive VHA perceptions, including the potential for VHAs to promote aging in place. Participants discussed the challenges learning the technology and replacing old...

Polymers, 2021

This work aims to explore how ZnO nanoparticles enhance the mechanical, photoaging, and self clea... more This work aims to explore how ZnO nanoparticles enhance the mechanical, photoaging, and self cleaning properties of water borne acrylic coating. Micro/nano ZnO particles (at 2 wt.% of total solid resin) were dispersed into the acrylic polymer matrices using ultrasonication to understand the effect of the size of the coating properties. The effect of ZnO particles on the properties of composite coatings (25 µm of thick) have been evaluated through various tests, such as abrasion measurement, ultraviolet/condensation (UV/CON) weathering aging, and methylene blue self cleaning. Experimental data indicated that the incorporation of ZnO particles enhanced both abrasion resistance and methylene blue removal efficiency of the water borne acrylic coatings, with nano ZnO particles being the best. However, the weathering degradation of nanocomposite coatings was more severe as compared to the coating with micro ZnO (at the same ZnO content).

Journal of Composites Science, 2020

This study aims to evaluate the synergical effects of SiO2 nanoparticles (nano-SiO2) and organic ... more This study aims to evaluate the synergical effects of SiO2 nanoparticles (nano-SiO2) and organic photostabilizers (Tinuvin 384 (T384) and Tinuvin 292 (T292)) on the weathering resistance of acrylic polyurethane coating. Data obtained from infrared (IR), field emission scanning electron microscopy (FESEM), and weight loss of coatings (before and after aging test), suggest that the SiO2 nanoparticles play a dual role, as both reinforcer and UV absorber, thus improving effectively both the mechanical properties and the weathering resistance of polyurethane acrylic coatings. The nanocomposite coating containing 2 wt % nano-SiO2, 2 wt % T384, and 1 wt % T292 exhibits excellent weathering and abrasion resistances, offering a durable outdoor application.

ChemistrySelect, 2020

Magnetic resonance imaging (MRI) has emerged as one of the most promising techniques, which emplo... more Magnetic resonance imaging (MRI) has emerged as one of the most promising techniques, which employs nanoscience and imaging technology, for early diagnosis of the cancers. In this work, magnetic nanoparticles of Fe 3 O 4 @ poly(acrylic) acid (PAA) were synthesized using a low cost thermal decomposition method from iron ions precursor and utilized as a signal agent for MRI imaging. The Fe 3 O 4 magnetic nanoparticles obtained from FeCl 2 .4H 2 O precursor at the reaction temperature of 315°C in 1-octadcene solvent are of spherical shape with average diameter of 8.4 nm and high saturation magnetization (M s) of 60.05 emu/g. After phase transferred with PAA, the magnetic Fe 3 O 4 @PAA fluid is highly stable in a wide range of pHs solution (5-9) and wide range of NaCl concentrations (50-300 mM) with zeta potential of À 35.7 mV. The prepared Fe 3 O 4 @PAA fluid showed noncytotoxicity to the Hep-G2, MCF-7, RD cancer cell line and Vero healthy cell line. MRI in-vitro results showed that transverse relaxation rate r 2 was around 158.4 mM À 1 s À 1 and the signal intensity was not affected by the pHs solution and NaCl concentrations. In-vivo test on rabbit revealed the clear observation of rabbit's body parts after injection of the Fe 3 O 4 @PAA magnetic fluid with retention time of 90 minutes in the body.

Journal of Applied Polymer Science, 2020

This work aims to clarify the photocatalytic degradation mechanism and heat reflectance recovery ... more This work aims to clarify the photocatalytic degradation mechanism and heat reflectance recovery performance of waterborne acrylic polymer/ZnO nanocomposite coating. To fabricate the nanocomposite coating, ZnO nanoparticles (nano‐ZnO) were dispersed into acrylic polymer matrix at the various concentrations from 1 to 6% (by total weight of resin solids). The photocatalytic degradation of nanocomposite coating under ultraviolet (UV) light irradiation has been investigated by monitoring its weight loss and chemical/microstructural/morphological changes. As the topcoat layer, its heat reflectance recovery has been evaluated under UV/condensation exposure by using an artificial dirty mixture of 85 wt% nanoclay, 10 wt% silica particles (1–5 μm), 1 wt% carbon black, and 2 wt% engine oil. After 108‐cycle UV/condensation exposure, infrared spectra and weight loss analysis indicated that the maximal degradation for nanocomposite coating is observed at 1 wt% nano‐ZnO. On the other hand, after ...

Journal of Nanoscience and Nanotechnology, 2020

In this manuscript, biological durability, cytotoxicity and MRI image contrast effect of chitosan... more In this manuscript, biological durability, cytotoxicity and MRI image contrast effect of chitosan modified magnetic nanoparticles were investigated. The result of durability study shows that the asprepared sample with average size of about 30 nm had a high stability under pH conditions in range of from 2 to 12 and at salt concentration in range of from 0 to 300 mM. The cytotoxicity testing indicates that the obtained Fe3O4@CS ferrofluid revealed a low cytotoxicity. After 48 h of test on the line of prostate tumor cells of Sarcoma 180, collected IC50 value was 178.5±22 (μg/ml), 7.5 to 27.9 times less cytotoxicity than that of reported ferromagnetic fluids. MRI data shows that the transverse relaxation rate (r2) of the ferrite nanoparticles was 130.32 (mM−1s−1), 2 and 1.44 times larger than that of the commercial products of Sinerem (AMI-227) and Ferumoxytol products, respectively. Invivo test in rabbit shows that the picture of body parts was clearly observed after the injection of t...

Vietnam Journal of Science and Technology, 2018

Aging of waterborne paint on the base of acrylic resin emulsion with and without green Luconyl ha... more Aging of waterborne paint on the base of acrylic resin emulsion with and without green Luconyl have been investigated by general appearance assessment, adhesion change, FT-IR and discoloration. The obtained results showed that the both of paint-formulas coatings had no cracks, blisters, flacks and there was no change of adhesion during the aging process. However, IR analysis indicated that there were some changes in chemical structures of coating with and without Green Luconyl during aging process. To specify, IR spectrums of initial and aged coating no containing Green Luconyl illustrated aging process led content of O-H and C=C increased significantly but baseline of spectra was fairly unchanged. For coating filled Green Luconyl, IR spectrums’ shape was fairly stable but baseline saw a clear reduce during accelerated weather exposure. Moreover, SEM images indicated that surfaces morphology of samples changed differently depending on in presence of organic pigment. Surface of aged ...

Progress in Organic Coatings, 2019

In this paper, an antibacterial nanocomposite coating has been prepared by a green method based o... more In this paper, an antibacterial nanocomposite coating has been prepared by a green method based on photocroslinking with the addition of new synthesized Fe 3 O 4-Ag nanohybrids. Fe 3 O 4-Ag hybrid nanoparticles (0.1 wt. %) were dispersed in UV-curable acrylate resin stystem (BGDM and HDDA). The kinetic of UV-curing reaction of the nanocomposite was studited by measuring the coversion of acrylate double bonds, the variation of relative hardness, gel fraction and swelling degree of the coating. The structural morphology, mechanical and antibacterial properties of the nanocomposite were characterized. The analysis data demonstrated that the addition of 0.1 wt.% of Fe 3 O 4-Ag hybrid nanoparticles into the coating affected insignificantly to its crosslinking process; the UV-exposure time to achieve a full crosslinking coating was about 4.8 s; the hybrid nanoparticles were homogeneously dispersed in network polymer matrix. The addition of the nanohybrids into the UV curing coating improved its its abrasion resistance from 98.24 to 126.54 lite/mil. The antibacterial testing indicated that the antimicrobial activity of the nanocomposite against E. coli was inversely proportional to its crosslinking density. Adding the nanocomposite in the culture, the growth rate of culture reduced about 3-5 % compared to that of the pure culture, after 5 h of cultivation while no antibacterial activity was observed for the neat coating.

Progress in Organic Coatings, 2019

In this work, Fe 3 O 4-Ag hybrid nanoparticles were homogeneously dispersed into acrylic polyuret... more In this work, Fe 3 O 4-Ag hybrid nanoparticles were homogeneously dispersed into acrylic polyurethane matrix at a concentration of 0.1% (by the total weight of acrylic polyols and polyisocyanates). The curing process of this nanocomposite coating has been investigated by monitoring the change of coating hardness and variation of isocyanate/urethane groups (through their optical density in IR analysis) and gel fraction analysis. The surface morphology and mechanical properties of the nanocomposite coating were characterized. The antibacterial test was performed by monitoring the bacterial lag-log growth phase with the presence of nanocomposite coating in the E. coli cell culture reactor. The IR and relative hardness analysis datas indicated that the full curing time of nanocomposite coating was 6 days. The results of IR, coating hardness and gel fraction measurements indicated that crosslinking process of coating was insignificantly affected by the presence of Fe 3 O 4-Ag hybrid nanoparticles. The incorporation of hybrid nanoparticles into the acrylic polyurethane coating increased its adhesion (from 2.15 to 2.21 N/mm 2) and its impact resistance (from 110 to 125 Kg. cm −1). The antibacterial test showed that the presence of nanocomposite coating exhibited good antibacterial activity against E. coli, whereas no antibacterial activity was observed for the neat coating.

SSRN Electronic Journal, 2018

Does it matter whether a government is prompt or slow in consolidating outstanding debt? We addre... more Does it matter whether a government is prompt or slow in consolidating outstanding debt? We address this question by studying the connection between the time variation of the persistence of government-debt-to-output ratio, macroeconomic activity, and asset prices. In the US, when government debt is sluggish, consumption exhibits lower expected growth, more long-run uncertainty, and more long-run downside risk. Simultaneously, the risk premium on the consumption claim (Koijen et al. (2010), Lustig et al. (2013)) increases and features more positive (adverse) skewness. We rationalize these findings in an endogenous growth model in which (i) fiscal policy is distortionary, (ii) the value of innovation depends on fiscal risk, and (iii) the representative agent is sensitive to the resulting distribution of consumption risk. Our model suggests that committing to a rapid reduction of the debt-to-output ratio can enhance the value of innovation, aggregate wealth, and hence welfare.

Operative neurosurgery (Hagerstown, Md.), Jan 15, 2018

Survival outcomes for patients with liver disease who suffer an intracranial hemorrhage (ICH) hav... more Survival outcomes for patients with liver disease who suffer an intracranial hemorrhage (ICH) have not been thoroughly investigated. To understand survival outcomes for 3 groups: (1) patients with an admission diagnosis of liver disease (end-stage liver disease [ESLD] or non-ESLD) who developed an ICH in the hospital, (2) patients with ESLD who undergo either operative vs nonoperative management, and (3) patients with ESLD on the liver transplant waitlist who developed an ICH in the hospital. We retrospectively reviewed hospital charts from March 2006 through February 2017 of patients with liver disease and an ICH evaluated by the neurosurgery service at a single academic medical center. The primary outcome was survival. We included a total of 53 patients in this study. The overall survival for patients with an admission diagnosis of liver disease who developed an ICH (n = 29, 55%) in the hospital was 22%. Of those patients with an admission diagnosis of liver disease, 27 patients a...

Journal of neurosurgery, Jan 22, 2018

OBJECTIVE Meningiomas that appear hypervascular on neuroimaging could be amenable to preoperative... more OBJECTIVE Meningiomas that appear hypervascular on neuroimaging could be amenable to preoperative embolization. However, methods for measuring hypervascularity have not been described, nor has the benefit of preoperative embolization been adjudicated. The objective of this study was to show a relationship between flow void volume (measured on MRI) and intraoperative estimated blood loss (EBL) in nonembolized meningiomas. METHODS The authors performed volumetric analyses of 51 intracranial meningiomas (21 preoperatively embolized) resected at their institution. Through the use of image segmentation software and a voxel-based segmentation method, flow void volumes were measured on T2-weighted MR images. This metric was named the Meningioma Vascularity Index (MVI). The primary outcomes were intraoperative EBL and perioperative blood transfusion. RESULTS In the nonembolized group, the MVI correlated with intraoperative EBL when controlling for tumor volume (r = 0.55, p = 0.002). The MVI...

World neurosurgery, Jan 10, 2018

To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon... more To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon) to those determined by Adaptive Hybrid Surgery (AHS) operative planning software in 7 patients with vestibular schwannoma (VS). Four attending surgeons (3 neurosurgeons and 1 ear, nose, and throat surgeon) manually contoured planned residual tumors volumes for 7 consecutive patients with VS. Next, the AHS software determined the ideal radiosurgical target volumes based on a specified radiotherapy plan. Our primary measure was the difference between the average planned residual tumor volumes and the ideal radiosurgical target volumes defined by AHS (dRV). We included 7 consecutive patients with VS in this study. The planned residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (1.6 vs. 4.5 cm, P = 0.004). On average, the actual post-operative residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (2.2 cm vs...

Brain tumor research and treatment, 2018

Head computed tomography (CT) is instrumental for managing patients of all ages. However, its low... more Head computed tomography (CT) is instrumental for managing patients of all ages. However, its low dose radiation may pose a low but non-zero risk of tumor induction in pediatric patients. Here, we present a systematic literature review on the estimated incidence of brain tumor induction from head CT exams performed on children and adolescents. MEDLINE was searched using an electronic protocol and bibliographic searches to identify articles related to CT, cancer, and epidemiology or risk assessment. Sixteen studies that predicted or measured head CT-related neoplasm incidence or mortality were identified and reviewed. Epidemiological studies consistently cited increased tumor incidence in pediatric patients (ages 0-18) exposed to head CTs. Excess relative risk of new brain tumor averaged 1.29 (95% confidence interval, 0.66-1.93) for pediatric patients exposed to one or more head CTs. Tumor incidence increased with number of pediatric head CTs in a dose-dependent manner, with measurab...

Progress in Organic Coatings, 2017

In this study, the high UV-shielding nanocomposite coatings based on pure acrylic emulsion and R-... more In this study, the high UV-shielding nanocomposite coatings based on pure acrylic emulsion and R-TiO 2 /or ZnO nanoparticles were successfully prepared. The effect of the nanoparticles on the photostability and UV shielding efficiency has been studied by using a UV/condensation weathering chamber equipped with UVB-313 fluorescent lamps. The obtained results showed that the coatings with the 2 wt% R-TiO 2 /or ZnO nanoparticles and a thickness of 45 m have the highest UV-shielding and photostability. These coatings could shield more than 98% (for R-TiO 2) and 85% (for ZnO) of UV radiations in wavelength range from 230 to 380 nm. After 60 cycles of UV/CON exposure, color of coating samples protected by the R-TiO 2 and ZnO nanocomposite coatings change insignificantly, their adhesion only decreased slightly, from their initial values of 2.5 and 2.4 to the values of 2.3 and 2.1 N/mm 2 , respectively. These nanocomposite coatings have possibly a promising potential for UV shielding applications.

International Journal of Polymer Science, 2016

For the vulcanized natural rubber (NR), incorporation of silver nanoparticles (AgNPs) into the NR... more For the vulcanized natural rubber (NR), incorporation of silver nanoparticles (AgNPs) into the NR matrix did not exhibit the bactericidal property against Escherichia coli (E. coli). However, incorporation of AgNPs into polyethylene (PE) matrix showed good antibacterial activities to both Gram-negative and Gram-positive bacteria. In the present work, NR/PE (85/15) blends have been prepared by melt blending with presence of compatibilizer in an internal mixer. To possess antibacterial property, AgNPs (5–10 nm) or Fe3O4–Ag hybrid nanoparticles (FAgNPs, 8 nm/16 nm) were added into PE matrix before its blending with NR component. The tensile test indicated that the presence of compatibilizer in NR/PE blend significantly enhanced the tensile strength and elongation at break (up to 35% and 38% increases, resp.). The antibacterial activity test was performed by monitoring of the bacterial lag-log growth phases with the presence of nanocomposites in the E. coli cell culture reactor. The ant...

Tạp chí Y Dược học Cần Thơ, Sep 20, 2022

thuốc chống chỉ định chiếm tỷ lệ 7,8% và tương tác thuốc nghiêm trọng chiếm tỷ lệ 24,3% trong đơn... more thuốc chống chỉ định chiếm tỷ lệ 7,8% và tương tác thuốc nghiêm trọng chiếm tỷ lệ 24,3% trong đơn thuốc điều trị ngoại trú. Tương tác thuốc chống chỉ định chiếm tỷ lệ 5,8% và tương tác thuốc nghiêm trọng chiếm tỷ lệ 11% trong hồ sơ bệnh án điều trị nội trú. Có mối liên quan giữa độ tuổi của bệnh nhân, số lượng thuốc sử dụng trong đơn thuốc và khả năng xảy ra tương tác thuốc có ý nghĩa thống kê (p<0,05). Kết luận: Độ tuổi của bệnh nhân càng cao, số lượng thuốc sử dụng càng nhiều thì nguy cơ xảy ra tương tác thuốc càng cao. Cần sàng lọc tương tác thuốc bất lợi thường xuyên để đảm bảo an toàn cho bệnh nhân và tránh các tác dụng không mong muốn. Từ khóa: Phối hợp thuốc, tương tác thuốc, đơn thuốc, bệnh án.

JMIR Formative Research, 2021

Background Medication nonadherence is a global public health challenge that results in suboptimal... more Background Medication nonadherence is a global public health challenge that results in suboptimal health outcomes and increases health care costs. Forgetting to take medicines is one of the most common reasons for unintentional medication nonadherence. Research findings indicate that voice-activated virtual home assistants, such as Amazon Echo and Google Home devices, may be useful in promoting medication adherence. Objective This study aims to create a medication adherence app (skill), MedBuddy, for Amazon Echo devices and measure the use, usability, and usefulness of this medication-taking reminder skill. Methods A single-group, mixed methods, cohort feasibility study was conducted with women who took oral contraceptives (N=25). Participants were undergraduate students (age: mean 21.8 years, SD 6.2) at an urban university in the Southeast United States. Participants were given an Amazon Echo Dot with MedBuddy—a new medication reminder skill for Echo devices created by our team—att...

JMIR Formative Research, 2022

International Journal of Environmental Research and Public Health, 2021

Aim: Describe virtual home assistant use and usefulness from the perspective of older adults and ... more Aim: Describe virtual home assistant use and usefulness from the perspective of older adults and their support persons. Methods: This was a mixed-methods study with older adults and their support persons (n = 10 dyads). Virtual home assistant (VHA) equipment was installed in participants’ homes, and its use was documented for 60 days. Participants received protocol-guided telephone calls to address their VHA questions or problems. The type and frequency of VHA use were summarized with descriptive statistics. End-of-study interviews about VHA use were conducted with dyad participants. Qualitative content analyses were used to describe the interview findings about the dyad’s perceptions of using the VHA, how it was used, any difficulties experienced, and suggestions for future VHA uses. Results: Participant dyads reported positive VHA perceptions, including the potential for VHAs to promote aging in place. Participants discussed the challenges learning the technology and replacing old...

Polymers, 2021

This work aims to explore how ZnO nanoparticles enhance the mechanical, photoaging, and self clea... more This work aims to explore how ZnO nanoparticles enhance the mechanical, photoaging, and self cleaning properties of water borne acrylic coating. Micro/nano ZnO particles (at 2 wt.% of total solid resin) were dispersed into the acrylic polymer matrices using ultrasonication to understand the effect of the size of the coating properties. The effect of ZnO particles on the properties of composite coatings (25 µm of thick) have been evaluated through various tests, such as abrasion measurement, ultraviolet/condensation (UV/CON) weathering aging, and methylene blue self cleaning. Experimental data indicated that the incorporation of ZnO particles enhanced both abrasion resistance and methylene blue removal efficiency of the water borne acrylic coatings, with nano ZnO particles being the best. However, the weathering degradation of nanocomposite coatings was more severe as compared to the coating with micro ZnO (at the same ZnO content).

Journal of Composites Science, 2020

This study aims to evaluate the synergical effects of SiO2 nanoparticles (nano-SiO2) and organic ... more This study aims to evaluate the synergical effects of SiO2 nanoparticles (nano-SiO2) and organic photostabilizers (Tinuvin 384 (T384) and Tinuvin 292 (T292)) on the weathering resistance of acrylic polyurethane coating. Data obtained from infrared (IR), field emission scanning electron microscopy (FESEM), and weight loss of coatings (before and after aging test), suggest that the SiO2 nanoparticles play a dual role, as both reinforcer and UV absorber, thus improving effectively both the mechanical properties and the weathering resistance of polyurethane acrylic coatings. The nanocomposite coating containing 2 wt % nano-SiO2, 2 wt % T384, and 1 wt % T292 exhibits excellent weathering and abrasion resistances, offering a durable outdoor application.

ChemistrySelect, 2020

Magnetic resonance imaging (MRI) has emerged as one of the most promising techniques, which emplo... more Magnetic resonance imaging (MRI) has emerged as one of the most promising techniques, which employs nanoscience and imaging technology, for early diagnosis of the cancers. In this work, magnetic nanoparticles of Fe 3 O 4 @ poly(acrylic) acid (PAA) were synthesized using a low cost thermal decomposition method from iron ions precursor and utilized as a signal agent for MRI imaging. The Fe 3 O 4 magnetic nanoparticles obtained from FeCl 2 .4H 2 O precursor at the reaction temperature of 315°C in 1-octadcene solvent are of spherical shape with average diameter of 8.4 nm and high saturation magnetization (M s) of 60.05 emu/g. After phase transferred with PAA, the magnetic Fe 3 O 4 @PAA fluid is highly stable in a wide range of pHs solution (5-9) and wide range of NaCl concentrations (50-300 mM) with zeta potential of À 35.7 mV. The prepared Fe 3 O 4 @PAA fluid showed noncytotoxicity to the Hep-G2, MCF-7, RD cancer cell line and Vero healthy cell line. MRI in-vitro results showed that transverse relaxation rate r 2 was around 158.4 mM À 1 s À 1 and the signal intensity was not affected by the pHs solution and NaCl concentrations. In-vivo test on rabbit revealed the clear observation of rabbit's body parts after injection of the Fe 3 O 4 @PAA magnetic fluid with retention time of 90 minutes in the body.

Journal of Applied Polymer Science, 2020

This work aims to clarify the photocatalytic degradation mechanism and heat reflectance recovery ... more This work aims to clarify the photocatalytic degradation mechanism and heat reflectance recovery performance of waterborne acrylic polymer/ZnO nanocomposite coating. To fabricate the nanocomposite coating, ZnO nanoparticles (nano‐ZnO) were dispersed into acrylic polymer matrix at the various concentrations from 1 to 6% (by total weight of resin solids). The photocatalytic degradation of nanocomposite coating under ultraviolet (UV) light irradiation has been investigated by monitoring its weight loss and chemical/microstructural/morphological changes. As the topcoat layer, its heat reflectance recovery has been evaluated under UV/condensation exposure by using an artificial dirty mixture of 85 wt% nanoclay, 10 wt% silica particles (1–5 μm), 1 wt% carbon black, and 2 wt% engine oil. After 108‐cycle UV/condensation exposure, infrared spectra and weight loss analysis indicated that the maximal degradation for nanocomposite coating is observed at 1 wt% nano‐ZnO. On the other hand, after ...

Journal of Nanoscience and Nanotechnology, 2020

In this manuscript, biological durability, cytotoxicity and MRI image contrast effect of chitosan... more In this manuscript, biological durability, cytotoxicity and MRI image contrast effect of chitosan modified magnetic nanoparticles were investigated. The result of durability study shows that the asprepared sample with average size of about 30 nm had a high stability under pH conditions in range of from 2 to 12 and at salt concentration in range of from 0 to 300 mM. The cytotoxicity testing indicates that the obtained Fe3O4@CS ferrofluid revealed a low cytotoxicity. After 48 h of test on the line of prostate tumor cells of Sarcoma 180, collected IC50 value was 178.5±22 (μg/ml), 7.5 to 27.9 times less cytotoxicity than that of reported ferromagnetic fluids. MRI data shows that the transverse relaxation rate (r2) of the ferrite nanoparticles was 130.32 (mM−1s−1), 2 and 1.44 times larger than that of the commercial products of Sinerem (AMI-227) and Ferumoxytol products, respectively. Invivo test in rabbit shows that the picture of body parts was clearly observed after the injection of t...

Vietnam Journal of Science and Technology, 2018

Aging of waterborne paint on the base of acrylic resin emulsion with and without green Luconyl ha... more Aging of waterborne paint on the base of acrylic resin emulsion with and without green Luconyl have been investigated by general appearance assessment, adhesion change, FT-IR and discoloration. The obtained results showed that the both of paint-formulas coatings had no cracks, blisters, flacks and there was no change of adhesion during the aging process. However, IR analysis indicated that there were some changes in chemical structures of coating with and without Green Luconyl during aging process. To specify, IR spectrums of initial and aged coating no containing Green Luconyl illustrated aging process led content of O-H and C=C increased significantly but baseline of spectra was fairly unchanged. For coating filled Green Luconyl, IR spectrums’ shape was fairly stable but baseline saw a clear reduce during accelerated weather exposure. Moreover, SEM images indicated that surfaces morphology of samples changed differently depending on in presence of organic pigment. Surface of aged ...

Progress in Organic Coatings, 2019

In this paper, an antibacterial nanocomposite coating has been prepared by a green method based o... more In this paper, an antibacterial nanocomposite coating has been prepared by a green method based on photocroslinking with the addition of new synthesized Fe 3 O 4-Ag nanohybrids. Fe 3 O 4-Ag hybrid nanoparticles (0.1 wt. %) were dispersed in UV-curable acrylate resin stystem (BGDM and HDDA). The kinetic of UV-curing reaction of the nanocomposite was studited by measuring the coversion of acrylate double bonds, the variation of relative hardness, gel fraction and swelling degree of the coating. The structural morphology, mechanical and antibacterial properties of the nanocomposite were characterized. The analysis data demonstrated that the addition of 0.1 wt.% of Fe 3 O 4-Ag hybrid nanoparticles into the coating affected insignificantly to its crosslinking process; the UV-exposure time to achieve a full crosslinking coating was about 4.8 s; the hybrid nanoparticles were homogeneously dispersed in network polymer matrix. The addition of the nanohybrids into the UV curing coating improved its its abrasion resistance from 98.24 to 126.54 lite/mil. The antibacterial testing indicated that the antimicrobial activity of the nanocomposite against E. coli was inversely proportional to its crosslinking density. Adding the nanocomposite in the culture, the growth rate of culture reduced about 3-5 % compared to that of the pure culture, after 5 h of cultivation while no antibacterial activity was observed for the neat coating.

Progress in Organic Coatings, 2019

In this work, Fe 3 O 4-Ag hybrid nanoparticles were homogeneously dispersed into acrylic polyuret... more In this work, Fe 3 O 4-Ag hybrid nanoparticles were homogeneously dispersed into acrylic polyurethane matrix at a concentration of 0.1% (by the total weight of acrylic polyols and polyisocyanates). The curing process of this nanocomposite coating has been investigated by monitoring the change of coating hardness and variation of isocyanate/urethane groups (through their optical density in IR analysis) and gel fraction analysis. The surface morphology and mechanical properties of the nanocomposite coating were characterized. The antibacterial test was performed by monitoring the bacterial lag-log growth phase with the presence of nanocomposite coating in the E. coli cell culture reactor. The IR and relative hardness analysis datas indicated that the full curing time of nanocomposite coating was 6 days. The results of IR, coating hardness and gel fraction measurements indicated that crosslinking process of coating was insignificantly affected by the presence of Fe 3 O 4-Ag hybrid nanoparticles. The incorporation of hybrid nanoparticles into the acrylic polyurethane coating increased its adhesion (from 2.15 to 2.21 N/mm 2) and its impact resistance (from 110 to 125 Kg. cm −1). The antibacterial test showed that the presence of nanocomposite coating exhibited good antibacterial activity against E. coli, whereas no antibacterial activity was observed for the neat coating.

SSRN Electronic Journal, 2018

Does it matter whether a government is prompt or slow in consolidating outstanding debt? We addre... more Does it matter whether a government is prompt or slow in consolidating outstanding debt? We address this question by studying the connection between the time variation of the persistence of government-debt-to-output ratio, macroeconomic activity, and asset prices. In the US, when government debt is sluggish, consumption exhibits lower expected growth, more long-run uncertainty, and more long-run downside risk. Simultaneously, the risk premium on the consumption claim (Koijen et al. (2010), Lustig et al. (2013)) increases and features more positive (adverse) skewness. We rationalize these findings in an endogenous growth model in which (i) fiscal policy is distortionary, (ii) the value of innovation depends on fiscal risk, and (iii) the representative agent is sensitive to the resulting distribution of consumption risk. Our model suggests that committing to a rapid reduction of the debt-to-output ratio can enhance the value of innovation, aggregate wealth, and hence welfare.

Operative neurosurgery (Hagerstown, Md.), Jan 15, 2018

Survival outcomes for patients with liver disease who suffer an intracranial hemorrhage (ICH) hav... more Survival outcomes for patients with liver disease who suffer an intracranial hemorrhage (ICH) have not been thoroughly investigated. To understand survival outcomes for 3 groups: (1) patients with an admission diagnosis of liver disease (end-stage liver disease [ESLD] or non-ESLD) who developed an ICH in the hospital, (2) patients with ESLD who undergo either operative vs nonoperative management, and (3) patients with ESLD on the liver transplant waitlist who developed an ICH in the hospital. We retrospectively reviewed hospital charts from March 2006 through February 2017 of patients with liver disease and an ICH evaluated by the neurosurgery service at a single academic medical center. The primary outcome was survival. We included a total of 53 patients in this study. The overall survival for patients with an admission diagnosis of liver disease who developed an ICH (n = 29, 55%) in the hospital was 22%. Of those patients with an admission diagnosis of liver disease, 27 patients a...

Journal of neurosurgery, Jan 22, 2018

OBJECTIVE Meningiomas that appear hypervascular on neuroimaging could be amenable to preoperative... more OBJECTIVE Meningiomas that appear hypervascular on neuroimaging could be amenable to preoperative embolization. However, methods for measuring hypervascularity have not been described, nor has the benefit of preoperative embolization been adjudicated. The objective of this study was to show a relationship between flow void volume (measured on MRI) and intraoperative estimated blood loss (EBL) in nonembolized meningiomas. METHODS The authors performed volumetric analyses of 51 intracranial meningiomas (21 preoperatively embolized) resected at their institution. Through the use of image segmentation software and a voxel-based segmentation method, flow void volumes were measured on T2-weighted MR images. This metric was named the Meningioma Vascularity Index (MVI). The primary outcomes were intraoperative EBL and perioperative blood transfusion. RESULTS In the nonembolized group, the MVI correlated with intraoperative EBL when controlling for tumor volume (r = 0.55, p = 0.002). The MVI...

World neurosurgery, Jan 10, 2018

To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon... more To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon) to those determined by Adaptive Hybrid Surgery (AHS) operative planning software in 7 patients with vestibular schwannoma (VS). Four attending surgeons (3 neurosurgeons and 1 ear, nose, and throat surgeon) manually contoured planned residual tumors volumes for 7 consecutive patients with VS. Next, the AHS software determined the ideal radiosurgical target volumes based on a specified radiotherapy plan. Our primary measure was the difference between the average planned residual tumor volumes and the ideal radiosurgical target volumes defined by AHS (dRV). We included 7 consecutive patients with VS in this study. The planned residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (1.6 vs. 4.5 cm, P = 0.004). On average, the actual post-operative residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (2.2 cm vs...

Brain tumor research and treatment, 2018

Head computed tomography (CT) is instrumental for managing patients of all ages. However, its low... more Head computed tomography (CT) is instrumental for managing patients of all ages. However, its low dose radiation may pose a low but non-zero risk of tumor induction in pediatric patients. Here, we present a systematic literature review on the estimated incidence of brain tumor induction from head CT exams performed on children and adolescents. MEDLINE was searched using an electronic protocol and bibliographic searches to identify articles related to CT, cancer, and epidemiology or risk assessment. Sixteen studies that predicted or measured head CT-related neoplasm incidence or mortality were identified and reviewed. Epidemiological studies consistently cited increased tumor incidence in pediatric patients (ages 0-18) exposed to head CTs. Excess relative risk of new brain tumor averaged 1.29 (95% confidence interval, 0.66-1.93) for pediatric patients exposed to one or more head CTs. Tumor incidence increased with number of pediatric head CTs in a dose-dependent manner, with measurab...

Progress in Organic Coatings, 2017

In this study, the high UV-shielding nanocomposite coatings based on pure acrylic emulsion and R-... more In this study, the high UV-shielding nanocomposite coatings based on pure acrylic emulsion and R-TiO 2 /or ZnO nanoparticles were successfully prepared. The effect of the nanoparticles on the photostability and UV shielding efficiency has been studied by using a UV/condensation weathering chamber equipped with UVB-313 fluorescent lamps. The obtained results showed that the coatings with the 2 wt% R-TiO 2 /or ZnO nanoparticles and a thickness of 45 m have the highest UV-shielding and photostability. These coatings could shield more than 98% (for R-TiO 2) and 85% (for ZnO) of UV radiations in wavelength range from 230 to 380 nm. After 60 cycles of UV/CON exposure, color of coating samples protected by the R-TiO 2 and ZnO nanocomposite coatings change insignificantly, their adhesion only decreased slightly, from their initial values of 2.5 and 2.4 to the values of 2.3 and 2.1 N/mm 2 , respectively. These nanocomposite coatings have possibly a promising potential for UV shielding applications.

International Journal of Polymer Science, 2016

For the vulcanized natural rubber (NR), incorporation of silver nanoparticles (AgNPs) into the NR... more For the vulcanized natural rubber (NR), incorporation of silver nanoparticles (AgNPs) into the NR matrix did not exhibit the bactericidal property against Escherichia coli (E. coli). However, incorporation of AgNPs into polyethylene (PE) matrix showed good antibacterial activities to both Gram-negative and Gram-positive bacteria. In the present work, NR/PE (85/15) blends have been prepared by melt blending with presence of compatibilizer in an internal mixer. To possess antibacterial property, AgNPs (5–10 nm) or Fe3O4–Ag hybrid nanoparticles (FAgNPs, 8 nm/16 nm) were added into PE matrix before its blending with NR component. The tensile test indicated that the presence of compatibilizer in NR/PE blend significantly enhanced the tensile strength and elongation at break (up to 35% and 38% increases, resp.). The antibacterial activity test was performed by monitoring of the bacterial lag-log growth phases with the presence of nanocomposites in the E. coli cell culture reactor. The ant...