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In this work, lignin based epoxy acrylate (LBEA) oligomer with various percentage of lignin was in situ synthesized with epoxy and acrylic acid. The first step was the etherification between lignin and epoxy to produce lignin based epoxy (LBE), and the second step was the esterification between LBE and acrylic acid to synthesize LBEA. Epoxy value and acid value were measured to determine the reaction conditions of the two steps, respectively. The structure of prepared LBEA was confirmed by Flourier infrared spectroscopy (FTIR) characterization. LBEA coatings were prepared through ultraviolet radiation curing method. The gel content, chemical resistance, mechanical properties and thermal properties of coatings were investigated. It was found that the mechanical properties and chemical resistance were much improved than those of epoxy acrylate (EA) resin with the addition of lignin. Thus, lignin was proved to be a new promising biomaterial which could be applied in biobased EA coatings. [ABSTRACT FROM AUTHOR]

Abstract: Recently, the influence of molecular weight (Mn) on the performance of polymer solar cells (PSCs) is widely investigated. However, the dependence of optimal thickness of active layer for PSCs on Mn is not reported yet, which is vital to the solution printing technology. In this work, the effect of Mn on the efficiency and especially optimal thickness of the active layer for PBTIBDTT‐S‐based PSCs is systematically studied. The device efficiency improves significantly as the Mn increases from 12 to 38 kDa, and a remarkable efficiency of 10.1% is achieved, which is among the top efficiencies of wide‐bandgap polymer:fullerene PSCs. Furthermore, the optimal thickness of the active layer is also greatly increased from 62 to 210 nm with increased Mn. Therefore, a device employing a thick (>200 nm) active layer with power conversion efficiency exceeding 10% is achieved by manipulating Mn. This exciting result is attributed to both the improved crystallinity, thus hole mobility, and preferable polymer orientation, thus morphology of active layer. These findings, for the first time, highlight the significant impact of Mn on the optimal thickness of active layer for PSCs and provide a facile way to further improve the performance of PSCs employing a thick active layer. [ABSTRACT FROM AUTHOR]

A red-emitting fluorescent probe for selective detection of cysteine was developed based on the conjugated addition/cyclization sequence mechanism. Upon the treatment with cysteine, this probe exhibits a strong fluorescence enhancement (62-fold) and a large Stokes shift (148 nm). The detection limit was calculated to be as low as 6.6 nM based on S/N = 3. Importantly, the practical application of this probe for the selective detection of cysteine was successfully demonstrated in living cells. [ABSTRACT FROM AUTHOR]

Objective: To present an effective approach to trophectoderm biopsy for blastocysts of different stages and characteristics by mechanical blunt dissection (MBD).Design: Stepwise demonstration with still pictures and operational video clips to explain tips and tricks for trophectoderm biopsy. (This demonstration was approved by the Reproductive Study Ethics Committee at Shengjing Hospital of China Medical University.) SETTING: In vitro fertilization laboratory.Patient(s): Patients who underwent preimplantation genetic testing.Intervention(s): The illustrated techniques of blastocyst trophectoderm biopsy using micromanipulation methods include artificial shrinkage, zona pellucida drilling, injecting media from the drilling, aspiration of trophectoderm cells into the biopsy pipette (outer diameter 27 μm for fully expanded blastocysts and peanut-shaped hatching blastocysts; outer diameter 20 μm for 8-shaped hatching and hatched blastocysts), detachment of the trophectoderm cells by laser pulse combined with MBD (performed using the rims of the biopsy and holding pipettes), and release of the biopsy fragment.Main Outcome Measure(s): Successful biopsy rate and survival after warming.Result(s): Our biopsy strategy does not involve assisted hatching on day-3 or day-4 embryos, which can leave the embryo undisturbed in culture up to the expanded blastocyst stage. Notably, this approach demonstrates several noteworthy advantages for sampling blastocysts of different stages and characteristics, and it maintains a desirable successful biopsy rate (95.4%, n = 1,872) and survival rate after warming (100%, n = 440). The MBD method may reduce thermal damage because fewer laser pulses are used, compared with the traditional laser-only biopsy techniques. For noncollapsed blastocysts after artificial shrinkage, the strategy of injecting medium from the zona pellucida drilling helps to separate the trophectoderm cells from the zona pellucida, thus facilitating the biopsy procedure. For peanut-shaped hatching blastocysts, this approach could provide better control over the aspiration of trophectoderm cells into the biopsy pipette. Especially if the inner cell mass is herniating from the zona pellucida, the trophectoderm biopsy can be performed away from the inner cell mass to avoid damaging it. In addition, the MBD approach combined with the biopsy pipette (outer diameter 20 μm) can effectively control the target number of trophectoderm cells, thus simplifying the process of obtaining a biopsy from a hatched blastocyst.Conclusion(s): Our biopsy approach demonstrates several noteworthy advantages. Considering its benefits and the simplicity of its execution, this systematic biopsy method for blastocysts of different stages and characteristic can be widely applied. [ABSTRACT FROM AUTHOR]

With the development of experimental teaching and scientific research in colleges and universities, laboratory safety management is playing an increasingly important role. Problems such as rigid system, outdated equipment and weak safety awareness are main factors which could cause accidents during the process of laboratory management. To ensure that the experimental environment meets the standards of practical teaching, laboratory equipment needs to be regularly updated and the management system that contradicts the concrete operation should also be adjusted. This paper discusses the combination of PDCA and laboratory safety management, followed by a discussion of its strengths and weaknesses. In the PDCA, the laboratory safety management is divided into four sections with various tasks, so that the entire process can be a sustainable cycle . The ultimate purpose is to reduce the possibility of safety accident in laboratories. [ABSTRACT FROM AUTHOR]

To present a novel trophectoderm biopsy method, independent of laser pulses, using innovatively designed micropipettes on blastocysts at different stages and show variable characteristics. A step-by-step demonstration of this method with narrated video. In vitro laboratory fertilization. Individuals whose embryos underwent preimplantation genetic testing. Trophectoderm biopsy is accomplished using micropipettes that contain a set of innovative designs. Both biopsy and holding pipettes are characterized by sharp, flat opening ends. The holding pipette is designed with an inclined plane on the outer wall surface of its opening end. It is used to help the biopsy pipette make contact with the holding pipette with increased stability, preventing slipping during the detachment of the trophectoderm cells. There is a narrow structure inside the biopsy pipette, which is designed to trap released fragments and prevent sample loss. A trophectoderm biopsy for fully expanded blastocysts starts from artificial shrinkage, followed by zona pellucida drilling. Then, 5–10 trophectoderm cells are aspirated into a biopsy pipette. The blastocyst is released from the holding pipette, the edge of the opening end of the biopsy pipette is tightly pressed onto the inclined plane of the holding pipette, and the biopsy pipette is flicked directly without laser pulses or pulling off the trophectoderm cells. The aspirated trophectoderm cells are subsequently detached by mechanical friction between the edges of the biopsy and holding pipettes. Apart from drilling the zona pellucida for fully expanded blastocysts, the remaining steps do not require lasers. For hatching (including peanut-shaped and 8-shaped) and hatched blastocysts, a trophectoderm biopsy is accomplished by aspirating the cells without securing the blastocyst with a holding pipette, followed by detachment using the direct flicking method. The biopsy time, sample loss rate, successful DNA amplification rate, and survival rate. The innovatively designed micropipettes facilitate the successful detachment of trophectoderm cells through a single direct flicking procedure. This eliminates thermal damage caused by laser pulses, notably simplifying operational steps and shortening the biopsy time. Significant differences were noted between the direct flicking and conventional methods, wherein laser pulses and pulling of trophectoderm cells are prerequisites for cell detachment. When comparing the average biopsy time of fully expanded blastocyst (61 ± 8s vs. 104 ± 9s, P <.05), peanut-shaped hatching blastocyst (35 ± 6s vs. 113 ± 13s, P <.05), 8-shaped hatching blastocyst (32 ± 4s vs. 59 ± 6s, P <.05), and hatched blastocyst (34 ± 4s vs. 67 ± 8s, P <.05), the direct flicking method shows a significantly decreased biopsy time. The narrow structure inside the biopsy pipette effectively prevents sample loss, showing a significantly reduced sample loss rate (0%) compared with the conventional biopsy method (18%) for trainees. Moreover, a satisfactory survival rate (100%) and successful DNA amplification rate (99.5%) were achieved using the direct flicking method. This innovative trophectoderm biopsy method, independent of laser pulses, has wide applicability and a satisfactory, stable performance. Moreover, the simplicity of the method makes it easy to master. [ABSTRACT FROM AUTHOR]

Abstract: Currently, constructing ternary organic solar cells (OSCs) and developing nonfullerene small molecule acceptors (n‐SMAs) are two pivotal avenues to enhance the device performance. However, introducing n‐SMAs into the ternary OSCs to construct thick layer device is still a challenge due to their inferior charge transport property and unclear aggregation mechanism. In this work, a novel wide band gap copolymer 4,8‐bis(4,5‐dioctylthiophen‐2‐yl) benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl‐alt‐N‐(2‐hexyldecyl)‐5,5′‐bis(thiophen‐2‐yl)‐2,2′‐bithiophene‐3,3′‐dicarboximide (PDOT) is designed and blend of PDOT:PC71BM achieves a power conversion efficiency (PCE) of 9.5% with active layer thickness over 200 nm. The rationally selected n‐SMA based on a bulky seven‐ring fused core (indacenodithieno[3,2‐b]thiophene) end‐capped with 2‐(3‐oxo‐2,3‐dihydroinden‐1‐ylidene) malononitrile groups (ITIC) is introduced into the host binary PDOT:PC71BM system to extend the absorption range and reduce the photo energy loss. After fully investigating the morphology evolution of the ternary blends, the different aggregation behavior of n‐SMAs with respect to their fullerene counterpart is revealed and the adverse effect of introducing n‐SMAs on charge transport is successfully avoided. The ternary OSC delivers a PCE of 11.2% with a 230 nm thick active layer, which is among the highest efficiencies of thick layer OSCs. The results demonstrate the feasibility of using n‐SMAs to construct a thick layer ternary device for the first time, which will greatly promote the efficiency of thick layer ternary devices. [ABSTRACT FROM AUTHOR]

The influences of optical scattering property, film thickness and annealing temperature of zinc oxide (ZnO) buffer layers on the performance of inverted polymer solar cells were systematically investigated. The ZnO films were prepared by ultrasonic spray coating, and the optical scattering property was manipulated by the precise adjustment of the operation conditions. It was found that the higher diffusive transmission of the ZnO film resulted in the higher short circuit current but the lower power conversion efficiency (PCE). With the optimum spray parameters, the suitable film thickness and annealing temperature for ZnO buffer layers were found, and the PCE of the corresponding inverted PSCs reached to 6.7%. This study is highly valuable in the technology transfer of polymer solar cells from lab to industry. [ABSTRACT FROM AUTHOR]

A spray-coating method, named as partially overlapped spray-coating (POSC) with winding path, was developed to deposit homogenous film over large area and employed to fabricate polymer solar cell (PSC) modules. The photoactive layer consisting of the conjugated polymer PBTI3T and the fullerene derivative PCBM[70] was obtained by optimizing the ink formulations and spray-coating parameters, which determines the morphology and film thickness. The lab-scale PSC (0.09 cm 2 ) fabricated by the POSC technique achieved a power conversion efficiency (PCE) of 6.63%, which is comparable to the spin-coated one. The POSC technique was then applied to up-scaling fabrication of PSC modules. A PCE as high as 5.27% was achieved for the module with 38.5 cm 2 photoactive area, which is so far the highest one with comparable size, to the best of our knowledge. It shows the POSC technique developed in this work is very successful for fabricating high-performance PSC modules, which paves a new way for film deposition in continuous roll-to-roll production. [ABSTRACT FROM AUTHOR]

A new crystallizable low band gap conjugated copolymer BTT ‐ DTFFBT is designed and synthesized. The polymer solar cells based on BTT ‐ DTFFBT: PC71BM photoactive layer are fabricated and characterized. It is found that after combined treatment of 1 vol % 1 ‐ chloronaphthalene (CN) additive and thermal annealing at 180 °C for 10 min, the device shows a power conversion efficiency (PCE) of 5.61% and good thermal stability. [ABSTRACT FROM AUTHOR]

A series of brominated polystyrenes (BPSs) are readily synthesized and blended as polymer dopants with the p-type semiconducting polymer, poly(3-hexylthiophene) (P3HT), to improve theirelectrical performance. The obtained P3HT/BPS blend films exhibit increased carrier concentration resulting from doping of P3HT by BPS, which leads to excellent electrical performance, including enhanced hole mobility and conductivity, and the conductivity or mobility increases with the bromination degree of BPS. Compared with conventional small molecular dopants, the polymer dopant, BPS, shows not only excellent doping stability, but also good solution processibility, which makes it a promising materials for fabrication of low cost, flexible, transparent, and high performance solution processable organic electronic devices. [ABSTRACT FROM AUTHOR]

In this work, we synthesized a low bandgap polymer polysilole(-2,6-diyl-alt-5-octylthieno[3,4- c]pyrrole-4,6-dione) (PDTSTPD) with different molecular weights ( Mn). The devices based on PDTSTPD/PC71BM composite are prepared and the dependence of power conversion efficiency (PCE) of the devices on the Mn of conjugated polymers is addressed. We found the hole mobility of PDTSTPD is dependent on the Mn of the polymer, which should be the main reason contributing to the drastic difference of device performance, i.e. the PCE of the device using 10 kDa polymer is only 0.52%, in contrast to 2.3% for 24 kDa polymer device. This PCE data is then further improved to 5.0% via using 1,8-diiodoctane as processing additive to achieve an optimized morphology for the photoactive layer with an appropriate length-scale of phase separation for both exciton dissociation and charge transportation. [ABSTRACT FROM AUTHOR]

Study Question: Is minimally invasive chromosome screening (MICS) using blastocyst culture medium (BCM) sufficiently fast and accurate for preimplantation genetic testing (PGT).Summary Answer: A new assay for MICS, named MICS-Inst achieved high-resolution, comprehensive chromosome ploidy detection using BCM.What Is Known Already: BCM is a viable source of genomic DNA for use in PGT.Study Design, Size, Duration: Forty-one vitrified blastocysts donated by 22 couples known to carry a chromosome rearrangement and 21 vitrified blastocysts donated from 8 couples with normal karyotypes were used in this study. Good-quality blastocysts, defined as Day 5 and Day 6 embryos ≥ BB (AA, AB, BA, BB) based on the Gardner system were used for analysis. Recruitment took place from May 2018 to August 2018. We performed PGT for structural rearrangements (PGT-SR) on 41 BCM, trophectoderm (TE) biopsy and blastocyst-stage embryo (BE) samples as well as PGT for aneuploidies (PGT-A) on 21 BCM, TE biopsy and BE samples.Participants/materials, Setting, Methods: We made several significant modifications to the BCM composition (mixing blastocoel fluid and spent blastocyst medium) as well as the pre-existing multiple annealing and looping-based amplification cycles (MALBAC) techniques and library generation procedures. The design of a quasilinear preamplification (Pre-AMP) primer and AMP primers 1 and 2 enables the preparation of a next-generation sequencing library after the exponential amplification stage by introducing the Illumina P5 and P7 primers into the final products, which are then ready for sequencing. Sequencing was performed on the Illumina Hiseq 2500 platform with 2.0 Mb raw reads generated for each sample.Main Results and the Role Of Chance: For PGT-A, BCM and TE biopsy samples showed 90% and 86% clinical concordance with the corresponding BE samples, respectively. In addition, both BCM and TE biopsy samples showed 76% karyotype concordance with the corresponding BE samples. For PGT-SR, we successfully obtained ploidy information for all 23 chromosomes with the exception of any rearrangements involving the Y chromosome. Both BCM and TE biopsy samples showed 100% clinical concordance with the corresponding BE samples in detecting chromosomal rearrangements. BCM and TE biopsy samples showed 90% and 100% karyotype concordance with the corresponding BE samples, respectively. Additionally, no statistically significant differences were detected in the aforementioned values of the BCM and TE biopsy samples in either PGT-A or PGT-SR (P > 0.05). Moreover, we achieved accurate quantification of segmental abnormalities using BCM samples. In addition, MICS-Inst reduced the number of steps required for library preparation through the use of new primer designs, resulting in an overall time reduction of 7.5 h. This time reduction allows for the performance of fresh blastocyst transfers.Limitations, Reasons For Caution: The main limitation is that BE, rather the inner cell mass, was used as the standard to evaluate the chromosome screening results.Wider Implications Of the Findings: These results show that MICS-Inst is effective in procedure and precision for PGT, and that it is possible to achieve fresh blastocyst transfer following PGT. The implications are significant, as these findings may lead to minimally invasive PGT methods in the future.Study Funding/competing Interest(s): This work was supported by the National Natural Science Foundation of China (No. 81671423 and No. 81402130), the National Key Research and Development Program of China (No. 2018YFC1003100), Liaoning Provincial Key Research and Development Program (No. 2018225090), the Fok Ying Tung Education Foundation (No. 151039) and Distinguished Talent Program of Shengjing Hospital (No. ME76). No competing interests declared. [ABSTRACT FROM AUTHOR]

Nickel acetate (Ni(Ac) 2 ) was successfully introduced to the low band-gap system for the first time and incorporated as the anode interlayer in conventional polymer solar cells (PSCs). For PBDT-TS1/PC 71 BM system, the device based on as-prepared Ni(Ac) 2 performs a lower power conversion efficiency (PCE) of 6.26% in comparison to that of PEDOT:PSS-based device (6.56%). After appropriate pre-bias treatment, the device efficiency rapidly increases to 7.27%, which is 11% and 16% higher than that of PEDOT:PSS- and as-prepared Ni(Ac) 2 -based device, respectively, due to the suppressed charge recombination and enhanced hole transport at anode interface. More importantly, device with pre-bias treated Ni(Ac) 2 as anode interlayer exhibits significantly improved lifetime in N 2 atmosphere. The Ni(Ac) 2 -based PSCs could maintain almost 85% of its original PCE after 200 h, while PEDOT:PSS-based PSCs only retains 60% of its original efficiency. This work demonstrates that the low-cost Ni(Ac) 2 is an ideal anode interlayer material, which could simultaneously improve the device efficiency and stability, to replace the widely used and high-cost PEDOT:PSS. [ABSTRACT FROM AUTHOR]

A fluorescent probe, 1,4-diethyl-7-(3-pyridin-2-yl-acroyloyl)-1,2,3,4-tetrahydro-5-oxa-1,4-diazaanthracen-6-one (probe 1 ), with an emission in near-infrared region was developed for sensitive and selective detection of biothiols. Probe 1 is essentially non-fluorescent due to the strong intramolecular charge transfer (ICT) from the electron-donating tetrahydroquinoxaline moiety to the electron-withdrawing pyridine group. Upon the treatment with biothiols, the conjugation system was broken via Michael addition reaction between biothiols and α,β-unsaturated ketone, which inhibited the ICT process and resulted in a remarkable fluorescence enhancement with an emission maximum at 660 nm. Moreover, probe 1 was successfully applied to image intracellular thiols in living cells. [ABSTRACT FROM AUTHOR]

Although the power conversion efficiency (PCE) of small-area polymer solar cells (PSCs) has now surpassed 10% upon various optimizations, it is still a challenge to improve the performance of large-area device partially due to the problems encountered in film morphology optimization and incompatibility of using these optimizations for size scale-up. Herein, we reported a method to effectively improve the morphology of photoactive layer and thus device efficiency under ambient atmosphere by using spray coating technique. It was found that by finely adjusting the parameters of the instrument, and the properties of the “electronic ink”, the dynamics of solvent evaporation after film deposition could be controlled. By resorting to a few techniques for morphology characterization, it confirmed that the resulting blend film showed desirable vertical phase separation where polymer enriched near the anode and PCBM adjacent to the cathode. The graded composition is beneficial for the efficient charge transportation as well as eventual charge collection. By using PBDT-TFQ/PC 71 BM composite as an example, the exceptional high PCEs of 4.6% and 4.1% were achieved for the devices with the size of 1.0 and 10.2 cm 2 , respectively. In comparison to conventional device fabrication process, this method is not only simple without additional treatment steps, but also dramatically increases the device efficiency, which opens a new way for fabricating highly efficient large-area PSCs. [ABSTRACT FROM AUTHOR]