Tripedal DNA Walker as a Signal Amplifier Combined with a Potential-Resolved Multicolor Electrochemiluminescence Strategy for Ultrasensitive Detection of Prostate Cancer Staging Indicators.

A multicolor electrochemiluminescence (ECL) biosensor based on a closed bipolar electrode (BPE) array was proposed for the rapid and intuitive analysis of three prostate cancer staging indicators. First, [Irpic-OMe], [Ir(ppy)2(acac)], and [Ru(bpy)3]2+ were applied as blue, green, and red ECL emitters, respectively, whose mixed ECL emission colors covered the whole visible region by varying the applied voltages. Afterward, we designed a simple Mg2+-dependent DNAzyme (MNAzyme)-driven tripedal DNA walker (TD walker) to release three output DNAs. Immediately after, three output DNAs were added to the cathodic reservoirs of the BPE for incubation. After that, we found that the emission colors from the anode of the BPE changed as a driving voltage of 8.0 V was applied, mainly due to changes in the interfacial potential and faradaic currents at the two poles of the BPE. Via optimization of the experimental parameters, cutoff values of such three indicators at different clinical stages could be identified instantly with the naked eye, and standard precision swatches with multiple indicators could be prepared. Finally, in order to precisely determine the prostate cancer stage, the multicolor ECL device was used for clinical analysis, and the resulting images were then compared with standard swatches, laying the way for accurate prostate cancer therapy.

Asymmetric Total Synthesis of (+)-Chuanxiongnolide L1 via a Stereoselective Oxidative Dearomatization/Diels-Alder Strategy.

The first asymmetric total synthesis of chuanxiongnolide L1 was achieved in 16 steps and 1.9% overall yield by employing a bioinspired chiral auxiliary strategy. The key steps involving asymmetric oxidative dearomatization of chiral amino ether and subsequent asymmetric Diels-Alder reaction of the resulting masked chiral ortho-benzoquinone were adopted.

Dual-signal ratiometric electrochemiluminescence biosensor based on Au NPs-induced low-potential emission of PFO Pdots and LSPR-ECL mechanism for ultra-sensitive detection of microRNA-141.

In this study, we have for the first time constructed a ratiometric ECL biosensor for the ultrasensitive detection of microRNAs (miRNAs) using gold nanoparticles (Au NPs) to trigger both the low-potential emission from conjugated polymer poly(9,9-dioctylfluorene-2,7-diyl) dots (PFO Pdots) and the LSPR-ECL effect with sulfur-doped boron nitride quantum dots (S-BN QDs). PFO Pdots were first applied to the Au NPs-modified electrode, followed by covalent binding to capture the hairpin H1. Immediately thereafter, a small amount of miRNA-141 was able to generate a large amount of output DNA (OP) by traversing the target cycle. OP, H3-S-BN QDs, and H4-glucose oxidase (H4-GOD) were then added sequentially to the Au NPs-modified electrode surface, and the hybridization chain reaction (HCR) was initiated. This resulted in the introduction of a large amount of GOD into the system, which catalyzed the in situ formation of the co-reactant hydrogen peroxide (H2O2) from the substrate glucose. Due to the electron transfer effect, the production of H2O2 led to the ECL quenching of PFO Pdots. Meanwhile, H2O2 served as a co-reactant of S-BN QDs, resulting in strong ECL emission of S-BN QDs at the cathode. Furthermore, the cathodic ECL intensity of S-BN QDs was further enhanced by an LSPR-ECL mechanism between Au NPs and S-BN QDs. By measuring the ratio of ECL intensities at two excitation potentials, this approach could provide sensitive and reliable detection of miRNA-141 in the range of 0.1 fM ∼10 nM, with a detection limit of 0.1 fM.

An 800-year record of benthic foraminifer images and 2D morphometrics from the Santa Barbara Basin.

The Santa Barbara Basin is an extraordinary archive of environmental and ecological change, where varved sediments preserve microfossils that provide an annual to decadal record of the dynamics of surrounding ecosystems. Of the microfossils preserved in these sediments, benthic foraminifera are the most abundant seafloor-dwelling organisms. While they have been extensively utilized for geochemical and paleoceanographic work, studies of their morphology are lacking. Here we use a high-throughput imaging method (AutoMorph) designed to extract 2D data from photographic images of fossils to produce a large image and 2D shape dataset of recent benthic foraminifera from two core records sampled from the center of the Santa Barbara Basin that span an ~800-year-long interval during the Common Era (1249-2008 CE). Information on more than 36,000 objects is included, of which more than 22,000 are complete or partially-damaged benthic foraminifera. The dataset also includes other biogenic microfossils including ostracods, pteropods, diatoms, radiolarians, fish teeth, and shark dermal denticles. We describe our sample preparation, imaging, and identification techniques, and outline potential data uses.

Level and influencing factors of transition shock among new nurses in China: A multicenter cross-sectional study.

Background and Aims: New nurses are an important part of nursing teams. The failure of new nurses to successfully transition seriously affects personal career development and nursing work quality, and important influencing factors deserve the attention of nursing managers. At present, multicenter, large-sample investigations of transition shock among new nurses are lacking in China. This study aims to investigate the current level and influencing factors of transition shock among new nurses in China. Methods: We conducted a multicenter, cross-sectional study with 3414 new nurses from 16 provinces in 7 regions in China from October 22, 2021, to November 8, 2021. We used the snowball sampling method and an online questionnaire produced by the researchers to collect data; the questionnaire included questions on demographic information, a transition shock scale for new nurses and open-ended questions. Data were analyzed using SPSS version 24. Results: The effective response rate of this study was 97.89%, with 3342 effective participants from 189 hospitals in China, most of whom were female (94.88%). The study showed that the transition shock of new nurses in China was at a moderate level, with pre-job anxiety, unsatisfactory welfare treatment, resignation intention, adverse events, poor sleep quality, 1 or fewer exercise sessions per week, inability to balance work and life, and gluttony negatively affecting the transition shock of new nurses in China. Psychological shock was the strongest among the four dimensions of transition shock. Conclusions: The transition shock of new nurses, especially their psychological shock, deserves more attention from international society. Nursing managers should continue to take supportive measures to intervene in the factors influencing transition shock, with the aim of reducing the level of transition for new nurses, promoting their personal thriving, improving the quality of nursing work and increasing the retention rate of nurses.