The Internet-of-Things (IoT) empowers remote monitoring and management of the performance of machines, vehicles, processes, etc., which facilitate service business models. However, companies in ...emerging and transitional economies, in particular, face challenges when applying IoT, not only related to the use of technology, but especially regarding the need for a new business model. The main goal of this paper is to better understand emerging IoT business models in Vietnam through identifying and interpreting business model design options and choices. The case studies and their commonalities are used to perform a morphological analysis and create a generic IoT business model providing business model alternatives for each of the four business model dimensions. The research provides insights into the commonalities and discrepancies of IoT-based business models. Also, it provides a novel application of morphological analysis to business model innovation to create a generic business model for IoT applications in emerging markets.
Unsubstituted and methylated polycyclic aromatic hydrocarbons (22 PAHs and 17 Me-PAHs) were examined in surface sediments collected from the Red River and four inner-city rivers of Hanoi City, ...Vietnam. Concentrations of total PAHs and Me-PAHs ranged from 52 to 920 (median 710) and from 70 to 2600 (median 1000) ng/g dry weight in samples of dry and wet seasons, respectively. Significant correlation was observed between total PAHs and organic carbon contents (Spearman's
ρ
= 0.782;
p
< 0.05). PAHs were more abundant than Me-PAHs in all samples and dominated by 4–6 ring compounds. The most predominant PAHs were benzo
ghi
perylene, benzo
b/j
fluoranthene, chrysene, pyrene, fluoranthene, and phenanthrene. Methylated derivatives of naphthalene, phenanthrene, anthracene, and benz
a
anthracene were frequently detected. The patterns of PAHs indicated principal pyrogenic sources (notably gasoline exhaust) in this highly urbanized area. The occurrence of several PAHs were occasionally associated with adverse effects on benthic organisms of the inner-city rivers.
Chemotherapy in cancer treatment usually leads to serious side effects on patients due to the unselectiveness and high toxicity on normal cells of cancer drugs. Loading cancer drugs into ...nano-platforms could be an alternative approach to effectively deliver drugs to tumors and reduce toxic exposure on healthy cells. In this work, we synthesized drug delivery nano-systems based on Fe
3
O
4
nanoparticles (obtained from co-precipitation reaction) which could provide targeting of drugs to the tumor sites by an external magnetic field. Also, the magnetic nanoparticles (MNPs) could generate heat to kill cancer cells at a certain temperature range. The systems were designed for loading anticancer agent doxorubicin by using alginate-coated iron oxide MNPs. It was found that the loading was achieved by complex formation of doxorubicin and the alginate layer. Various concentrations of alginate solutions produced different sizes as well as drug loading capacities of the nanoparticles. The highest loading content of 18.96% achieved at the alginate concentration of 4 mg ml
−1
, corresponding to the mass ratio of alginate to Fe
3
O
4
of around 1:2. The magnetic properties, especially the inductive heating effect of the nanoparticles, along with the impact of the systems on tumor cells were investigated. The results proved that the nanoparticles can serve as a good drug delivery system, in terms of both effective hyperthermia and chemotherapy.
Abstract
α-Thalassemia is a common inherited blood disorder manifested mainly by the deletions of α-globin genes. In geographical areas with high carrier frequencies, screening of α-thalassemia ...carrier state is therefore of vital importance. This study presents a novel method for identifying female carriers of common α-thalassemia deletions using samples routinely taken for non-invasive prenatal tests for screening of fetal chromosomal aneuploidies. A total of 68,885 Vietnamese pregnant women were recruited and α-thalassemia statuses were determined by gap-PCR, revealing 5344 women (7.76%) carried deletions including αα/−−
SEA
(4.066%), αα/−α
3.7
(2.934%), αα/−α
4.2
(0.656%), and rare genotypes (0.102%). A two-stage model was built to predict these α-thalassemia deletions from targeted sequencing of the HBA gene cluster on maternal cfDNA. Our method achieved F1-scores of 97.14–99.55% for detecting the three common genotypes and 94.74% for detecting rare genotypes (−α
3.7
/−α
4.2
, αα/−−
THAI
, −α
3.7
/−−
SEA
, −α
4.2
/−−
SEA
). Additionally, the positive predictive values were 100.00% for αα/αα, 99.29% for αα/−−
SEA
, 94.87% for αα/−α
3.7
, and 96.51% for αα/−α
4.2
; and the negative predictive values were 97.63%, 99.99%, 99.99%, and 100.00%, respectively. As NIPT is increasingly adopted for pregnant women, utilizing cfDNA from NIPT to detect maternal carriers of common α-thalassemia deletions will be cost-effective and expand the benefits of NIPT.
Rice straw open burning (RSOB) after harvest is one of the considerable emission sources in agricultural activities and contributed to air pollution in Vietnam. Determination of country/city-specific ...emission factors for air pollutants from open burning is important for the better estimation of air pollutant emission. In this research, hood experiments and field experiments were conducted simulating the common small pile burning type used by farmers in the North of Vietnam to determine emission factors (EFs) for gaseous pollutants, particulate matter (PM), and particle-bound polycyclic aromatic hydrocarbons (PAHs). The carbon_mass balance and emission ratio method were used to calculate EFs for the field experiments. The PM
2.5
emission factor obtained for open field burning (34.0 ± 17.6 g kg
−1
RS), the EFs for SO
2
(1.4 ± 1.1 g kg
−1
RS for field experiments and 1.82 ± 1.77 g kg
−1
RS for hood experiments) in this study was higher in comparison with the values reported in Thailand and China. Laboratory experiments showed positive correlation between RS carbon content and EF of CO
2
. The higher proportion and the contribution of benzo
a
pyrene (B
a
P) to the total 10 detected PAHs bound to PM
2.5
in RS burning smoke was the first observation in this study. Based on the EFs developed in this study, we estimated that RSOB released the amount of 369.6 Gg for CO
2
, 13.7 Gg for CO, 0.67 Gg for SO
2
, 0.35 Gg for NO
2
, 10.8 Gg for PM
2.5
, and 32 Mg for total 10 particle-bound PAHs to the atmosphere in Hanoi. These results are useful for integrated air-quality management in local as well as national scale.
Green macroalgae have gained attention as promising renewable sources for biorefining. Despite the wide potential availability of green macroalgae, their utilization has been limited to ethanol ...production, hindering their further application. In this study, we report that a bacterium,
Halomonas
sp. strain BL6 (isolated from a mangrove forest in Bach Long, Nam Dinh Province, Vietnam), produces pyruvate from a saccharified solution of the green seaweed
Ulva reticulata
and secretes it into the medium. Pyruvate, an important α-oxocarboxylic acid, plays a central role in energy and carbon metabolism in living organisms and is used mainly for the synthesis of various chemicals and polymers or as an ingredient or additive in food, cosmetics, and pharmaceuticals. To investigate the possibility of using
U. reticulata
from the seashore of Vietnam as biomass feedstock, the chemical composition and saccharification yield of this seaweed were studied. Dry biomass of
U. reticulata
was found to contain 65.5% carbohydrate, 10.3% protein, 1.8% lipid, and 10.6% ash. Reducing sugar content reached 608.79 mg g
−1
of biomass after pretreatment with diluted acid and 24 h of incubation with 50 IU g
−1
Viscozyme L. The resulting sugars were fermented by
Halomonas
sp. strain BL6 to produce pyruvate, and the maximal pyruvate concentration reached 55.23 g L
−1
after 72 h of cultivation. This study is the first to report the production of valuable compounds other than bioethanol products, such as pyruvate, from
U. reticulata
hydrolysate by a
Halomonas
strain.
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Herein, the fast and simple formation of triangular silver nanoparticles (T-Ag NPs) was systematically studied by a chemical reduction process with the assistance of light ...irradiation. The effects of sodium borohydride (NaBH4) concentration, pH medium, and light source irradiation are investigated via the localized surface plasmon resonances (LSPRs) detection of silver nanoparticles (Ag NPs). Results indicated that pH and light source are the two primary factors for the morphology of Ag NPs while NaBH4 plays an important role to control the formation rate of T-Ag NPs. Moreover, the photoreduction time for synthesis of T-Ag NPs is 180 min, and this method can be easily synthesized in any laboratory.
Adenosma bracteosum and Vitex negundo are natural sources of methoxylated flavonoids. Little is known about the α‐glucosidase inhibition of multi‐methoxylated flavonoid derivatives. Eighteen natural ...flavonoids were isolated from A. bracteosum and V. negundo. Seven halogenated derivatives were synthesized. Their chemical structures were elucidated by extensive NMR analysis and high‐resolution mass spectroscopy as well as comparisons in literature. All compounds were evaluated for their α‐glucosidase inhibition. Most compounds showed good activity with IC50 values ranging from 16.7 to 421.8 μM. 6,8‐Dibromocatechin was the most active compound with an IC50 value of 16.7 μM. A molecular docking study was conducted, indicating that those compounds are potent α‐glucosidase inhibitors.
Traditionally, lichen has been used for many purposes, but there remains a lack of understanding regarding the chemical composition and antimicrobial characteristics of
, a lichen native to Vietnam. ...In this study, four sesquiterpenes, diorygmones B-E (1-4), one phenolic compound, 3,5-dihydroxy-4-methoxybenzoic acid (5), and one sterol, β-sitosterol (6), were isolated and structurally elucidated from the cultured mycobiont of the lichen
. Additionally, two compounds, stictic acid (7) and norstictic acid (8), were also isolated from the lichen
Compounds 2-4 were new compounds. Their chemical structures were established using comprehensive spectroscopic data, and the absolute configurations were confirmed through the analysis of NOESY and electronic circular dichroism (ECD). Moreover,
, a Gram-positive bacterium, has been responsible for various infections, including food poisoning. Herein, we identified and isolated 13 strains of
from street food sources. Among these strains, one was identified as a multidrug-resistant variant, designated as SAX15, and was subsequently used for further antimicrobial testing. Compounds 1-3 produced zones of inhibition against
SAX15 (each 5 mm) in comparison to commercial drugs such as penicillin, ciprofloxacin, gentamicin, cefoxitin, and clarithromycin, which displayed inhibitory zones of 7, 5, 10, 9.7, and 7 mm, respectively.