In this study, we evaluated antioxidant, antihyperuricemic, and herbicidal activities of essential oils (EOs) from Piper cubeba Bojer and Piper nigrum L.; two pepper species widely distributed in tropics, and examined their chemical compositions. Dried berries of P. cubeba and P. nigrum were hydro-distilled to yield essential oil (EO) of 1.23 and 1.11% dry weight, respectively. In the antioxidant assay, the radical scavenging capacities of P. cubeba EO against DPPH and ABTS free radicals were 28.69 and 24.13% greater than P. nigrum, respectively. In the antihyperuricemic activity, P. cubeba EO also exhibited stronger inhibitory effects on xanthine oxidase (IC₅₀ = 54.87 µg/mL) than P. nigrum EO (IC₅₀ = 77.11 µg/mL). In the herbicidal activity, P. cubeba EO showed greater inhibition on germination and growth of Bidens pilosa and Echinochloa crus-galli than P. nigrum EO. Besides, P. cubeba EO decreased 15.98–73.00% of photosynthesis pigments of B. pilosa and E. crus-galli, while electrolyte leakages, lipid peroxidations, prolines, phenolics, and flavonoids contents were increased 10.82–80.82% at 1.93 mg/mL dose. Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analyses revealed that P. nigrum and P. cubeba EOs principally possessed complex mixtures of monoterpenes and sesquiterpenes. Terpinen-4-ol (42.41%), α-copaene (20.04%), and γ-elemene (17.68%) were the major components of P. cubeba EO, whereas β-caryophyllene (51.12%) and β-thujene (20.58%) were the dominant components of P. nigrum EO. Findings of this study suggest both P. cubeba and P. nigrum EOs were potential to treat antioxidative stress and antihyperuricemic related diseases. In addition, the EOs of the two plants may be useful to control B. pilosa and E. crus-galli, the two invasive and problematic weeds in agriculture practice.

As a promising candidate for expanding the capacity of drug loading in silica nanoplatforms, hollow mesoporous silica nanoparticles (HMSNs) are gaining increasing attention. In this study, porous nanosilica (PNS) and HMSNs were prepared by the sol-gel method and template assisted method, then further used for Rhodamine (RhB) loading. To characterize the as-synthesized nanocarriers, a number of techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen absorption-desorption isotherms, dynamic light scattering (DLS), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR) were employed. The size of HMSN nanoparticles in aqueous solution averaged 134.0 ± 0.3 nm, which could be adjusted by minor changes during synthesis, whereas that of PNS nanoparticles was 63.4 ± 0.6 nm. In addition, the encapsulation of RhB into HMSN nanoparticles to form RhB-loaded nanocarriers (RhB/HMSN) was successful, achieving high loading efficiency (51.67% ± 0.11%). This was significantly higher than that of RhB-loaded PNS (RhB/PNS) (12.24% ± 0.24%). Similarly, RhB/HMSN also possessed a higher RhB loading content (10.44% ± 0.02%) compared to RhB/PNS (2.90% ± 0.05%). From those results, it is suggested that prepared HMSN nanocarriers may act as high-capacity carriers in drug delivery applications.

Purposes: We conducted a cross-sectional descriptive study to evaluate the knowledge and practices of fall prevention among nurses in four departments in 7A Military Hospital, Ho Chi Minh City, Vietnam. Subjects and methods: Sixty-two nurses in four departments were chosen to fulfill pre-designed questionnaires, and their daily fall preventive practices were observed. Results: There were 40.3% of nurses achieve good knowledge of fall prevention. In practice, 22.5% of nurses had proper compliance, and 77.4% had not. 82.3% of nurses claimed to update fall prevention knowledge often, and 87.1% demanded training for fall prevention. Nurses in the surgical department group had more knowledge of fall prevention than nurses in the internal medicine group of departments (68.7% vs. 10.0%, p<0.05). Female nurses had higher fall risk compliances than males (78.3% vs. 37.5%, P<0.05). Conclusion: Training for nurses in fall preventive knowledge and practices are needed in 7A Military Hospital. Keywords: fall preventive; nurses; questionnaires; risk compliances.

Aim — 60 Vietnamese dry femurs were studied to design a carbon composite external fixator for intertrochanteric fracture. Its mechanical strength was evaluated. Material and Methods — The femurs were measured by standard goniometers. The fixator injection mold was created by a CNC machine. The fixator material included carbon fiber (30 – 40% content), BT4, and PA12 plastic. The fixator strength was calculated based on the Finite Element Method. Results — The average femoral neck-shaft angle, anteversion angle, bowing angle, head diameter, and neck width were respectively 124.850 (±7.12), 20.240 (±4.49), 14.900 (±3.27), 4.12cm (±0.30), and 3.05cm (±0.34). A mold and its resulting fixator were designed accordingly. The fixator elasticity modulus, tensile strength, Poisson ratio, and safety factor (K) were 1.32x1010 Pa, 2.21x108 Pa, 0.25, and 1.5, respectively, and max load, stress and transposition were 50-150 N, 1.21-1.38 x 108 Pa, and 0.4-1.27 mm, respectively. The composite fixator was more resistant against pressure across the x-axis but less against the y-axis than the chrome and Inox304 devices. Transposition was the smallest due to its tiny size. Load against z-axis pressure was safe for the patients. Conclusion — This study succeeded to design a prototype carbon composite external fixator with favorable mechanical traits compared with available metal fixators. Further clinical studies are needed to achieve an accurate evaluation of its effectiveness.