No abstract

This paper presents a one‐step method for the rapid synthesis of colloidal silver nanoparticles (AgNPs) for bacterial disinfection. Silver ions were electrochemically reduced to silver atoms in an AgNO3 solution with the assistance of an atmospheric argon microplasma jet. Dextran was used to stabilize the AgNPs in the liquid solution. Ultraviolet–visible spectroscopy, transmission electron microscopy, atomic force microscopy, and Fourier transform infrared spectroscopy were used to characterize the synthesized AgNPs. It was found that the size of the nanoparticles can be controlled by adjusting the dextran monomer/Ag+ molar ratio in the solution. Furthermore, antibacterial activity of the as‐synthesized AgNPs against Escherichia coli and Staphylococcus aureus was carried out in liquid as well as on solid growth media, as a function of the AgNPs concentration. The results showed that the AgNPs had a significant antibacterial activity against those bacteria cells and the minimum inhibition concentration was associated with the type of bacteria and initial bacterial concentration.

The influences of nsPEFs on the early physiological development of Haloxylon ammodendron were studied, and a growth stimulating effect after nsPEFs exposure were detected. We investigated the effect of nsPEFs on the germination rate and the radical lengths of H. ammodendron seed. Statistical analysis showed that pre-growth was significantly improved. In addition, the NO, pH of the liquid system after nsPEFs treatment were monitored. We inferred that NO and ORP were more positively involved in the early growth effects of H. ammodendron seed. Even if the underlying biophysical mechanism is still unclear, the result suggests the possibility to influence desert plant growth by using nsPEFs.

Desertification is one of world-wide environmental problems and it affects the livelihoods of millions of people, as it occur s on all continents. In order to prevent and reverse desertificat ion, reforestation is one of necessary approaches. Little plant can survive in the dry and extreme conditions in desert, and a mong these plants, Saxaul (Haloxylon ammodendron) is a ver y rare and successful species living in northwest China and m iddle Asia. Saxaul is less expensive and more effective; howe ver, direct seeding of this species, has not been promising. Al so, the seedlings of this species grow at a relatively slow rate, resulting in a mature and useful weapon against desertificati on in at least 4 or 5 years. A number of reasons have been pro posed to explain the unsuccessful plant establishment after se eding. Nanosecond pulsed electric fields, known as nsPEFs, h as shown to have accelerating effects on model plant growth r ate [1] [2] .In this study, the effects of nsPEFs on the germination, emerg ence and growth of the sexual seeds were observed and inves tigated. The seeds were exposed to 5 and 20 pulses with durat ion of 100ns at electric field intensity of 10, 20 and 30 kV/cm, separately. Parts of the treated and untreated (refers as "contr ol") seeds were placed on wet filter paper and for germinatio n, and the others were sowed in certain sand for long term gr owth. Germination percent of the treated seeds were higher th an control group after 24 hours, and the radical lengths of tre ated seeds were also longer after 48 hours. The treated seedli ngs emerged earlier than the control group. But when the ene rgy was too high, the stimulating effect changed into necrosis. Root lengths were also measured, and possible mechanism w as discussed in the paper. The nsPEFs with proper parameters may have potentials in improving the growth rate of Saxaul.1. W. Songnuan and P. Kirawanich, "Early growth effects on Arabidopsis thaliana by seed exposure of nanosecond pulsed

No abstract

No abstract

No abstract

Breast cancer is one of the major malignant tumors threatening the health of women. With the changes in people's lifestyle and diet, the incidence rate of breast cancer continues to rise all over the world. Despite the considerable progress in conventional cancer therapies such as surgery operation, radiotherapy, chemotherapy and incretion therapy, the intrinsic limitations of these therapies such as drug resistance still make the therapeutic effect dissatisfactory.