Although it is unclear how Zn
2+
cooperates with Cu
2+
in synergistic antibacterial activity, a 1:10 ratio of Cu
2+
/Zn
2+
atoms and ethylenediaminetetra-acetic acid and urea ligands can be used to ...form a chelation complex containing Cu
2+
and Zn
2+
. This study investigated the effects of the combination of Cu
2+
and Zn
2+
in chelation with EDTA and urea. The results were compared with the outcomes of either copper or zinc alone against gram-negative
Escherichia coli (E. coli
) and gram-positive
Staphylococcus aureus (S. aureus
) bacteria. The antibacterial activity was determined through MICs, disc diffusion method, and bacterial cell growth curves. In addition, bacterial destruction by this chelation complex has been observed through SEM images. The presence of copper ion and zinc ion inside the bacterial cells has been proved through EDS measurements. The obtained results allowed us to draw conclusions that the use of both Cu
2+
and Zn
2+
in a chelation complex with EDTA and urea enhances the antimicrobial activity against these bacteria. The bacterial inhibition of this complex was stronger than that of Cu
2+
alone chelated with EDTA or CuSO
4
solution by approximately 100-fold for
S. aureus
and 20-fold for
E. coli
.
This study presents the removal of phosphate from aqueous solution using a new silver nanoparticles-loaded tea activated carbon (AgNPs-TAC) material. In order to reduce costs, the tea activated ...carbon was produced from tea residue. Batch adsorption experiments were conducted to evaluate the effects of impregnation ratio of AgNPs and TAC, pH solution, contact time, initial phosphate concentration and dose of AgNPs-AC on removing phosphate from aqueous solution. Results show that the best conditions for phosphate adsorption occurred at the impregnation ratio AgNPs/TAC of 3% w/w, pH 3, and contact time lasting 150 min. The maximum adsorption capacity of phosphate on AgNPs-TAC determined by the Langmuir model was 13.62 mg/g at an initial phosphate concentration of 30 mg/L. The adsorption isotherm of phosphate on AgNPs-TAC fits well with both the Langmuir and Sips models. The adsorption kinetics data were also described well by the pseudo-first-order and pseudo-second-order models with high correlation coefficients of 0.978 and 0.966, respectively. The adsorption process was controlled by chemisorption through complexes and ligand exchange mechanisms. This study suggests that AgNPs-TAC is a promising, low cost adsorbent for phosphate removal from aqueous solution.
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.
The isolation, identification and characterization of a novel huperzine A (HupA)-producing fungal strain Rsp5.2 isolated from
Huperzia serrata
(Thunb. ex Murray) Trev. in Vietnam. The fifty-eight ...endophytic fungi were recovered from roots of natural
H. serrata
in Lao Cai province of northern Vietnam and screened for HupA-producing by thin-layer chromatography (TLC). The only one of the 58 strains, Rsp5.2, could produce HupA. The amount of HupA produced by Rsp5.2 was quantified to be 19.45 µg g
−1
dried mycelium by high-performance liquid chromatography (HPLC). Acetylcholine esterase (AchE) inhibition (IC
50
) of the crude HupA extract from Rsp5.2 fermentation broth was 2.849 ± 0.0026 µg mL
−1
. The fungus was identified as
Fusarium
sp. Rsp5.2 by morphological characteristics and Internal Transcribed Spacer (ITS) sequences. This is the first report of
Fusarium
sp. as a HupA-producing endophyte isolated from
H. serrata
.
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.
Elsewhere, Within Here Trinh, T Minh-Ha
2011, 20101018, 2010, 2010-10-25, 2010-10-18, 20110101
eBook
Winner of the 2012 Critics Choice Book Award of the American Educational Studies Association (AESA)
World-renowned filmmaker and feminist, postcolonial thinker Trinh T. Minh-ha is one of the most ...powerful and articulate voices in both independent filmmaking and cultural politics.
Elsewhere, Within Here is an engaging look at travel across national borders--as a foreigner, a tourist, an immigrant, a refugee—in a pre- and post-9/11 world. Who is welcome where? What does it mean to feel out of place in the country you call home? When does the stranger appear in these times of dark metamorphoses? These are some of the issues addressed by the author as she examines the cultural meaning and complexities of travel, immigration, home and exile. The boundary, seen both as a material and immaterial event, is where endings pass into beginnings. Building upon themes present in her earlier work on hybridity and displacement in the median passage, and illuminating the ways in which "every voyage can be said to involve a re-siting of boundaries," Trinh T. Minh-ha leads her readers through an investigation of what it means to be an insider and an outsider in this "epoch of global fear."
Elsewhere, Within Here is essential reading for those interested in contemporary feminist thought and postcolonial studies.
Trinh T. Minh-Ha is Professor of Rhetoric and of Gender and Women's Studies at the University of California, Berkeley. She is a leading feminist theorist, award-winning filmmaker, media artist, writer, composer, and cultural critic, and author of several influential and highly regarded books. She is particularly regarded for her work as a feminist and for the explorations of postcoloniality in her work. Her website is http://www.trinhminh-ha.com/.
Foreignness and The New Color of Fear
Story of the Wall
The Wall Event
The Call of The Tricolor Flag
I. Home: The Traveling Source
1. Far Away, From Home: The Comma Between
Sleepless Silence
The Tea and The Tear
The Debt of Love
Man of Tea
Children of Dragons and Immortals
The Century of Forgiveness?
2. Other Than Myself, My Other Self
Traveling Tales
A Stranger in a Strange Country
Wanderers Across Language
Their Country Is My Country
The Blue Frog
I, The Mis-seer
II. Boundary Event: Between Refuse and Refuge
3. An Acoustic Journey
Midway to Nowhere
"You Are The Battleground"
A Matter of Tuning
4. Nature's r: A Musical Swoon
Looking Back to The City of The Future
Boundary Event
Nature’s Becoming
Twilight Gray, Middle Gray
The Faded Charm of The Wolf
5. Voice Over I
Air (Your Tongue)
Earth (Your Lips)
Water (Your Saliva)
Light (The Way You Move)
6. The Paint of Music. A Performance Across Cultures
Essence – Performance
A Musical Accuracy
A Moment In and Out of Time
An Artless Balance
Making Music with Painting
III. No End in Sight
7. Mother's Talk
Stupidity and Memory
Wisdom and Memory
Wisdom’s Gender
Talk, More (Than) Talk
Tale Telling and The Texture of Memory
8. White Spring
The Page Screen
Red and Black: Voices of The Rain
Speaking Blind Through Camera Window
Death’s Voyeur: The All-in-One Diseuse
9. Detroit:
Incarcerated and Disappeared in The Land of The Free
Iron porphyrins are among the best molecular catalysts for the electrocatalytic CO2 reduction reaction. Powering these catalysts with the help of photosensitizers comes along with a couple of ...unsolved challenges that need to be addressed with much vigor. We have designed an iron porphyrin catalyst decorated with urea functions (UrFe) acting as a multipoint hydrogen bonding scaffold towards the CO2 substrate. We found a spectacular photocatalytic activity reaching unreported TONs and TOFs as high as 7270 and 3720 h−1, respectively. While the Fe0 redox state has been widely accepted as the catalytically active species, we show here that the FeI species is already involved in the CO2 activation, which represents the rate‐determining step in the photocatalytic cycle. The urea functions help to dock the CO2 upon photocatalysis. DFT calculations bring support to our experimental findings that constitute a new paradigm in the catalytic reduction of CO2.
The exceptionally high performance for CO2‐to‐CO photocatalytic reduction displayed by an iron–porphyrin bearing urea groups in the second coordination sphere is the result of the interaction of CO2 with the catalyst prior to the occurrence of the second electron uptake in the catalytic cycle.
This study aimed to investigate antimicrobial resistance profile, multidrug resistance (MDR), and molecular characteristics of pathogenic Staphylococcus aureus isolates from hospitalized Vietnamese ...adults. Two hundred and twenty-three pathogenic S. aureus isolates were obtained from the hospitals located in 3 regions of Vietnam. The minimum inhibitory concentrations were determined to detect the antibiotic susceptibility of the isolates. The molecular characteristics of S. aureus isolates were investigated through antibiotic-resistant genes analysis, staphylococcal cassette chromosome mec typing, pulsed-field gel electrophoresis, and multilocus sequence typing. Substantial differences among the 3 regions were found in the prevalence rates of methicillin-resistant S. aureus (north: 48.6%, central: 58.7%, south: 78.9%) and MDR (north: 65.8%, central: 79.7%, and south: 84.2%). The prevalence rates of the genes tetK/M, aacA/aphD, ermA/B/C, and mecA increased substantially from north to south. ST188-SCCmecIV and ST239-SCCmecII isolates were most commonly found in the 2 largest clusters. ST188 predominance was observed in the largest cluster in methicillin-resistant and methicillin-sensitive S. aureus isolates, including SCCmecIII and SCCmecIVa, in fatal cases. Our results revealed a high occurrence of MDR and possible north−south trend in antibiotic resistance profile, MDR patterns, and frequency of antibiotic-conferring genes among S. aureus isolates. ST188 predominance raises concerns about the global importance of host-adapted ST188 in East Asian populations.
Oil pollution in marine environment caused by oil spillage has been a main threat to the ecosystem including the ocean life and to the human being. In this research, three indigenous purple ...photosynthetic strains
Rhodopseudomonas
sp. DD4, DQ41, and FO2 were isolated from oil-contaminated coastal zones in Vietnam. The cells of these strains were immobilized on different carriers including cinder beads (CB), coconut fiber (CF), and polyurethane foam (PUF) for diesel oil removal from artificial seawater. The mixed biofilm formed by using CB, CF, and PUF as immobilization supports degraded 90, 91, and 95% of diesel oil (DO) with the initial concentration of 17.2 g/L, respectively, after 14 days of incubation. The adsorption of DO on different systems was accountable for the removal of 12–16% hydrocarbons for different carriers. To the best of our knowledge, this is the first report on diesel oil degradation by purple photosynthetic bacterial biofilms on different carriers. Moreover, using carriers attaching purple photosynthetic bacteria to remove diesel oil in large scale is considered as an essential method for the improvement of a cost-effective and efficient bioremediation manner. This study can be a promising approach to eliminate DO from oil-contaminated seawater.
Graphdiyne (GDY), which features a highly π‐conjugated structure, direct bandgap, and high charge carrier mobility, presents the major requirements for photocatalysis. Up to now, all photocatalytic ...studies are performed without paying too much attention on the GDY bandgap (1.1 eV at the G0W0 many‐body theory level). Such a narrow bandgap is not suitable for the band alignment between GDY and other semiconductors, making it difficult to achieve efficient photogenerated charge carrier separation. Herein, for the first time, it is demonstrated that tuning the electronic bandgap of GDY via H‐substitution (H‐GDY) promotes interfacial charge separation and improves photocatalytic H2 evolution. The H‐GDY exhibits an increased bandgap energy (≈2.5 eV) and exploitable conduction band minimum and valence band maximum edges. As a representative semiconductor, TiO2 is hybridized with both H‐GDY and GDY to fabricate a heterojunction. Compared to the GDY/TiO2, the H‐GDY/TiO2 heterojunction leads to a remarkable enhancement of the photocatalytic H2 generation by 1.35 times under UV–visible illumination (6200 µmol h−1 g−1) and four times under visible light (670 µmol h−1 g−1). Such enhancement is attributed to the suitable band alignment between H‐GDY and TiO2, which efficiently promotes the photogenerated electron and hole separation, as supported by density functional theory calculations.
Adjusting the electronic bandgap of graphdiyne is the next step to move forward and expand the use of graphdiyne in photochemical reactions. The H‐substitution of graphdiyne maintains the large π‐conjugated structure and enables enlarging the bandgap, which is beneficial to target the construction of type II heterostructured photocatalysts for efficient charge carrier separation and H2 generation.
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