Prospective open-label non-inferiority randomised controlled trial comparing letrozole and mifepristone pretreatment in medical management of first trimester missed miscarriage: study protocol.

INTRODUCTION: Medical treatment is a less invasive alternative to surgical management of missed miscarriage. Studies have shown that pretreatment with mifepristone can increase the complete abortion rate in management of first-trimester missed miscarriage compared with misoprostol alone. Two studies have also shown that pretreatment with letrozole could increase the efficacy compared with misoprostol alone. So far, there is no trial comparing letrozole and mifepristone pretreatment for missed miscarriage. We designed this randomised controlled trial to test the hypothesis that for first-trimester missed miscarriage, letrozole pretreatment is non-inferior to mifepristone pretreatment followed by misoprostol in terms of complete abortion rate. METHODS AND ANALYSIS: This is a prospective open-label non-inferiority randomised controlled trial conducted in a single centre. In total, 294 women diagnosed with first-trimester missed miscarriage opting for medical treatment is recruited with informed consent. They are randomly assigned to receive mifepristone or letrozole pretreatment. In the mifepristone group, each woman takes 200 mg mifepristone orally followed 24-48 hours later by 800 µg misoprostol vaginally. In the letrozole group, each woman takes 10 mg letrozole orally per day for 3 days, followed by 800 µg misoprostol vaginally on the third day of letrozole administration. Follow-up is conducted on days 15 and 42 after misoprostol administration. The primary outcome is the overall complete abortion rate. Secondary outcomes include side effects and complications during the study period. Data will be analysed with both intention-to-treat and per protocol approaches. A p<0.05 will be considered as indicating statistical significance. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Institutional Review Board of the University of Hong Kong-Shenzhen Hospital with approval number: (2020)166. Findings will be disseminated in a peer-reviewed journal and in national and/or international meetings to guide future practice. TRIAL REGISTRATION NUMBER: ChiCTR2000041480.

Numerical analysis of the precursory information of slope instability process with constant resistance bolt.

The instability of slope has already threatened life and property safety of the people, and improving the monitoring method of slope stability has important theoretical and practical significance for disaster prevention and reduction. According to the idea of "Newton force sudden drop and catastrophic occurrence" proposed by M.C. He in the landslide monitoring, a numerical model with constant resistance bolt has been established. Through numerical simulation research, it is found that the maximum principal stress, minimum principal stress and shear stress of the intersection point P of landslide surface and constant resistance bolt are sudden growth and sudden decrease, the vertical displacement and lateral displacement of this point P appear rise and fall before three kinds of stress. When loading to the next step of the step where three stress have reduced to a minimum value the slope is unstable and destroyed. At this time, the constant resistance bolt has undergone larger plastic deformation and damaged. Finally, comparing the stress curves and the acoustic emission (AE) curves, it can be seen that stress decreases from the maximum value and the AE curves begin to show a significant rise, the two curves display opposite law. It can be seen from the AE diagram that the failure mode of the slope is a combined tension and shear failure. The numerical test results provide a new idea for real-time monitoring and forecasting of slope.

A New Molecular Approach Based on the Secondary Structure of Ribosomal RNA for Phylogenetic Analysis of Mobilid Ciliates.

We analyzed the secondary structure of the small subunit (SSU) rRNA genes of Mobilida (Ciliophora, Peritrichia) and found that the secondary structures of some regions within the SSU-rRNA gene are distinct between the families Trichodinidae and Urceolariidae. Therefore, some of these important regions including H10, H11, H17, H47, H29, H30, H37, E10-1, H45-H46, and V4 (E23-4, E23-7) could be used as the barcodes for classification of these two families. In contrast, V4 (E23-1, E23-2) belongs to a hypervariable region and is not a good barcode at the genus level because of its great inter-specific variation. Our results indicated that the comprehensive analysis of the secondary structure of SSU-rRNA genes is a reliable auxiliary approach for phylogenic study of mobilid ciliates. It was further found that the coevolution between hosts or habitats and the Mobilida ciliates was existent, because the host types and their habitats were critical ecological factors that influenced the evolution of Mobilida ciliates.

[Progress in Application of Two-Dimensional Correlation Spectroscopy for Detection of Food Quality].

In recent years, the food safety and quality has always been a serious issue. Therefore, it is urgent to develop a rapid and widely available method to determine the quality of food. Due to high spectral resolution, good spectral selectivity and good ability of spectrogram analysis, the technology of two-dimensional (2D) correlation spectroscopy is an effective method for solving three major problems encountered by the conventional one-dimensional (1D) spectrum: low selectivity of the spectra, difficulty in extracting the information of the spectral feature and difficulty in spectrogram analysis. Therefore, 2D correlation spectroscopy, which is suited to distinguish similar samples hardly distinguished by the conventional 1D spectroscopy, has been successfully applied in many complex biological systems. The developmental process, the experimental way to obtain spectrum, the fundamental mathematical principle and the properties of 2D correlation spectroscopy were introduced in this paper. At the same time, it is pointed out that the origin of weak characteristic bands of substance can be verified in terms of the positive or negative corss peaks in synchronous 2D correlation spectrum combined with the existence or inexistence of corss peaks in asynchronous 2D correlation spectrum. The application of 2D near-infrared, mid-infrared, fluorescence, and raman correlation spectroscopy in the detection of food quality and adulteration, concentrated specifically on diary product, wine, oil, meat, honey, and rice were reviewed. Finally, the limitations and future development prospects were pointed out.

[Discrimination of adulterated milk based on Euclidian distances between two-dimensional infrared correlation spectra].

Based on Euclidian distances between synchronous two-dimensional infrared correlation spectra, in terms of the average Euclidian distances between unknown samples and "extreme samples", and average intra- and inter-Euclidian distances of samples in the calibration set, a new method for the discrimination of adulterated milk was proposed. Sixteen pure milk samples were collected and 16 adulterated milk samples with urea (0.01-0.3 g x L(-1)), and 16 adulterated milk samples with melamine (0.01-0.3 g x L(-1)) samples were prepared, respectively. The IR absorption spectra of all samples were measured at room temperature. The synchronous two-dimensional correlation spectra were generated from concentration-dependent spectral variation of adulterant in milk. The Euclidian distances were calculated between synchronous two-dimensional infrared correlation spectra of all samples. Then, the classification models were built respectively for adulterated milk with urea, and adiulterated milk with melamine. The "extreme samples", average intra- and inter-Euclidian distances were determined. Finally, the unknown samples in prediction set were predicted using constructed models in terms of classification rules of adulterated milk. The classification accuracy rates for pure milk and adulterated milk were 100%. The effectiveness of the proposed method was verified. The results obtained in this study revealed that synchronous two-dimensional infrared correlation spectra in combination with Euclidian distance has a feasible potential to discriminate adulterated milk and pure milk.