The microwave (MW) field can be measured by the Autler–Townes (AT) splitting of the electromagnetically induced transparency (EIT) spectrum in the Rydberg atomic system; however, the EIT-AT splitting method fails in weak MW fields. We used the amplitude modulation of the MW field to resolve the EIT-AT splitting in weak MW fields. The EIT-AT splitting interval can be directly obtained, and the minimum detectable MW strength is improved by six times compared with the traditional EIT-AT splitting method. The proposed method is more intuitive and convenient for measuring the strength of weak MW fields in practical applications.

Accumulating evidence suggests that acetyl-CoA acetryltransferase 1 (ACAT-1) may mediate tumor development and metastasis. However, the specific function served by ACAT-1 in lung cancer is not well understood. Therefore, the present study initially verified that ACAT-1 was overexpressed in Lewis lung carcinoma (LLC) tissues compared with non-LLC mice and that this overexpression promoted the proliferation, invasion and metastasis of these LLC samples. Western blotting, immunofluorescence microscopy and flow cytometry allowed the present study to determine that the ACAT-1 inhibitor avasimibe significantly reduced the expression of ACAT-1 in LLC compared with LLC cells that are not treated with avasimibe (P<0.05). A combination of Cell Counting Kit-8 and wound healing assays demonstrated that downregulating ACAT-1 expression sufficiently inhibited the proliferation of LLC cells. Avasimibe promoted LLC cell apoptosis as assessed by a Annexin V/propidium iodide double staining assay. Furthermore, avasimibe inhibited tumor growth in vivo and improved immune responses, with tissue biopsies from LLC model mice exhibiting higher levels of ACAT-1 compared with in healthy controls. Altogether, the results of the present study reveal that avasimibe may inhibit the progression of LLC by downregulating the expression of ACAT-1, which may thus be a potential novel therapeutic target for lung cancer treatment.

We have systematically investigated the influence of the gas temperature (T), the Rabi frequencies of the probe laser (Ωp), the coupling laser (Ωc) and the radio-frequency (ΩRF) on the Rydberg electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting (Δf) by defining a general Doppler mismatch factor Dg=ΩRF/Δf in the Rydberg atom-based microwave electrometry. The effect of T on Dg is studied in detail from 0 to 1000 K, the results show that Dg is insensitive to T when T<10 μK or T>10 K, while Dg changes significantly with 10 K>T>10 μK. Then the effects of Ωp, Ωc and ΩRF on factor Dg at T=300 K (typical room temperature) and T=10 μK (typical temperature of cold atom by laser cooling) are studied in detail, respectively. The results show that the linewidth of Rydberg EIT (ΓEIT) can be used as a key parameter to characterize the dependence of Dg on Ωp and Ωc in both cases. Dg is insensitive to T, Ωp and Ωc when ΩRF>3ΓEIT which means that ΓEIT determines the lower limit of the linear region of the radio-frequency (RF) electric field strength measured by EIT-AT splitting. More interesting, the range where Dg is insensitive to Ωp and Ωc can be greatly expanded by lowering the gas temperature to 10 μK. The ranges of parameters where Dg is insensitive to T, Ωp, Ωc and ΩRF are given, and such relationship can be easily scaled to other atomic systems. The results can help the selection of various parameters in the experiments and specific applications to ensure the accuracy of measuring the RF electric field.

Recently, a Rydberg atom-based mixer was developed to measure the phase of a radio frequency (RF) field. The phase of the signal RF (SIG RF) field is down-converted directly to the phase of a beat signal created by the presence of a local RF (LO RF) field. In this study, we propose that the Rydberg atom-based mixer can be converted to an all optical phase detector by amplitude modulation (AM) of the LO RF field; that is, the phase of the SIG RF field is related to both the amplitude and phase of the beat signal. When the AM frequency of the LO RF field is the same as the frequency of the beat signal, the beat signal will further interfere with the AM of the LO RF field inside the atom, and then the amplitude of the beat signal is related to the phase of the SIG RF field. The amplitude of the beat signal and the phase of the SIG RF field show a linear relationship within the range of 0 to π/2 when the phase of the AM is set with a difference π/4 from the phase of the LO RF field. The minimum phase resolution can be as small as 0.6 degree by optimizing the experimental conditions according to a simple theoretical model. This study will expand and contribute to the development of RF measurement devices based on Rydberg atoms.

Accumulating evidence suggests that celecoxib and artemisinin could mediate ovarian cancer development and metastasis. The present study investigated the effects of celecoxib and artemisinin on the epithelial-mesenchymal transition (EMT) characteristics of the human ovarian epithelial adenocarcinoma cell line, SKOV3. SKOV3 cells were incubated with celecoxib (10 µM) for different periods of time to establish an EMT cell model. Subsequently, artemisinin (20, 40 and 80 µM) was used to establish a cell model of the reverse process, mesenchymal-epithelial transition (MET). Cell proliferation, metastasis, invasiveness and the expression of vimentin and E-cadherin were measured using Cell Counting Kit-8, wound healing assay, western blotting, flow cytometry and immunofluorescence. The EMT cell model exhibited enhanced proliferative capacity, increased migration, increased vimentin expression and decreased E-cadherin expression. By contrast, artemisinin decreased proliferative capacity, decreased migration, decreased vimentin expression and increased E-cadherin expression of EMT model cells, indicating that MET was induced. These results demonstrated that artemisinin may reverse celecoxib-induced epithelial-mesenchymal transition in SKOV3 cells.