P Doping Promotes the Spontaneous Visible-Light-Driven Photocatalytic Water Splitting in Isomorphic Type II GaSe/InS Heterostructure

The development and design of clean and efficient water splitting photocatalysts is important for the current situation of energy shortage and environmental pollution. A new type of isomorphic GaSe/InS heterostructure is constructed, and the optoelectronic properties were studied through first-principles calculations. The results show that GaSe/InS vdW heterostructure is a type II semiconductor with a band gap of 2.09 eV. However, through the analysis of the energy band edge position and Gibbs free energy change of water splitting, it is found that the GaSe/InS heterostructure is difficult to undergo overall water splitting. Therefore, nonmetallic element P doping is considered, the established P-doped GaSe/InS (P-GaSe/InS) heterostructure could maintain the type II band arrangement, and under acidic conditions, P-GaSe/InS heterostructure could spontaneously undergo overall water splitting thermodynamically. Furthermore, the low exciton binding energy of P-GaSe/InS heterostructure highlights better light absorption performance. Therefore, these findings indicate that P-GaSe/InS heterostructure is a promising photocatalyst in overall water splitting.

[Study on the assignment method of intensity modulated radiotherapy plan for nasopharyngeal carcinoma based on MR images]

Objective: To discuss the influence of different computed tomography (CT) value assignment methods on dose calculation of intensity modulated radiotherapy (IMRT) plan which designed for nasopharyngeal carcinoma (NPC) and the value assignment methods of IMRT plan for NPC based on magnetic resonance (MR) images. Methods: Simulation CT and MR image of 32 NPC patients in Shandong Cancer Hospital from March 2018 to November 2018 were selected for this study. Populate CT values were obtained by contouring and analyzing the simulation CT of patients' tissue, including bone, air, brain, eyeball, optic-nerve, lens, parotid, masseter, skin. Pseudo-CT were generated by different CT value assignment methods: CT1: CT value of all tissues was set to 0HU; CT2: CT value of air cavity was set to populate CT value based on CT1; CT3: CT value of Bone was set to populate CT value based on CT2; CT4: CT value of each soft tissue were set to populate CT value based on CT3. The IMRT plan for NPC as Plan0 was designed base on simulation CT. Then Plan0 was transplanted to four pseudo-CT to recalculate the dose and obtain Plan1, Plan2, Plan3 and Plan4, the differences of dosimetric parameters were compared with Plan0. NPC-IMRT plan was designed base on MR images by using the assignment method with CT value of each tissue were set to populate CT value. Results: In the head and neck CT images, the average populate CT values of bone and cavity were 621 HU and -720 HU, respectively. The populate CT values of other soft tissue ranges from -20 HU to 70 HU. The differences of dosimetric indexes of Plan1, Plan2, Plan3, Plan4 decreased sequentially compare to Plan0, the difference of the dosimetry parameters of Plan4 and Plan0 was the smallest. The differences of PTV D(99), PTV D(95), isocenter dose, D(mean) of all tissues, D(max) of bilateral eye balls, D(max) of bilateral lens, D(max) of bilateral optic nerves, D(mean) of bilateral parotid, V(20) of bilateral parotid, D(50) of bilateral parotid, D(max) of spinal cord, D(max) of brainstem, D(5) of brainstem between Plan4 and Plan0 were all less than 1%. The difference of V(30) in bilateral parotid between Plan4 and Plan0 was less than 1.5%. In the comparison of the pixel dose distribution, the regions of dose distribution difference greater than 1% mainly distributed in the air cavity, bone periphery and the skin. The target area of the IMRT plan for NPC based on MR images met 95% of the prescribed dose, and the dose of each organ at risk was within the dose limit. Conclusions: The assignment method of each tissue and organs set to populate CT value compared with other methods has the least influence on the dose calculation of NPC-IMRT plan, which could meet the clinical requirements. Therefore, it should be the first choice of assignment method when designing NPC-IMRT plan based on MR image.

[Comparison of the post-operative analgesic effect of ultrasound-guided serratus anterior plane block combined with pectoral nerves block Ⅰ and thoracic paravertebral block in radical mastectomy]

Objective: To investigate the serratus anterior plane block combined with pectoral nerves block I can produce a non-inferior analgesic effect compared with thoracic paravertebral block for radical mastectomy. Methods: From October 2020 to February 2021, Sixty-four patients of Beijing Tongren Hospital, Capital Medical University scheduled for radical mastectomy with general anesthesia,were divided into two groups (n = 32 each) using a random number table method: thoracic paravertebral block group (TPVB group) and serratus anterior plane block combined with pectoral nerves block I group (S&P group). All patients received patient controlled intravenous analgesia (PCIA) postoperatively. The numerical rating scale (NRS) at post anesthesia care unit (PACU), 4, 8, 12, 24, 48 h after operation were compared between the two groups. Sufentanil cumulative dosage of PCIA in 24 h and 48 h, first press time after operation, total press times, the dosage of propofol, remifentanil and vasoactive drugs during operation, intraoperative blood pressure and heart rate, the operation time of block and adverse effects were all compared. Non-inferiority could be claimed if the difference of sufentanil cumulative dosage in 24 h between S&P group and TPVB group is higher than the negative value (-3.8) of the non-inferiority effect. Results: There was no significant difference in postoperative NRS at PACU, 4, 8, 12, 24, 48 h after operation, first press time after operation, total press times, propofol and remifentanil dosage, sufentanil cumulative dosage of PCIA in 24 h and 48 h, and adverse effects (all P>0.05). The sufentanil cumulative dosage of PCIA in 24 h of S&P group and of TPVB group were (15.8±4.7) μg and (15.2±3.2) μg. The 95% confidence interval (CI) of the difference between S&P group and of TPVB group was -1.478 to 2.694, and the lower limit was greater than non-inferiority margin -3.8. The mean arterial pressure of TPVB patients after induction and at the beginning of the operation were (63±7) mmHg and (70±7) mmHg, which were significantly lower than the (77±5) mmHg and (79±8) mmHg at the same time in the combination group (both P<0.05). The frequency of vasoactive drugs usage in TPVB group was 56.3%, which was statistically significant higher than the 18.8% in S&P group (P<0.01). Nerve block time in TPVB group was 10 (9, 11) min, which was significantly longer than 8 (6, 10) min in S&P group (P<0.01). Conclusion: The serratus anterior block combined with pectoral nerves block I can produce a non-inferior analgesic effect compared with thoracic paravertebral block for radical mastectomy, and the intraoperative hemodynamics is more stable and the block time is shorter than that of thoracic paravertebral block for radical mastectomy.

Atmospheric pressure plasma treatment induces abscisic acid production, reduces stomatal aperture and improves seedling growth in Arabidopsis thaliana

Cold atmospheric pressure plasmas (CAPPs) have been widely used for pre-sowing treatment in agriculture to accelerate seed germination; however, information on their application to pre-transplant seedlings is scarce. The roles of the phytohormone abscisic acid (ABA) on guard cell aperture that control air exchange with the environment were investigated after CAPPs treatment. In this study, Arabidopsis thaliana seedling growth was evaluated under CAPPs treatment at different doses. Besides, the optimal growth stimulation dose was selected to further evaluate changes in ABA, ROS, Ca²⁺ and stomatal aperture during growth .The expression of most ABA signalling genes were aslo examined to investigate the mechanism. CAPPs treatment for 1 min significantly promoted Arabidopsis seedling growth; the ABA concentration in seedlings increased and peaked 48 h after treatment but was lower than in the control after 96 h. Transcript levels of most ABA signalling genes were markedly enhanced at 48 h, although their transcripts were significantly downregulated after 96 h. CAPPs treatment also reduced stomatal aperture after 24 h and accelerated ROS accumulation in guard cells. The Ca²⁺ concentration in the treatment group was markedly higher than in the control at 24 and 96 h. The results suggest that CAPPs treatment accelerates ABA accumulation in Arabidopsis at early growth stages and ABA regulates ROS and Ca²⁺ concentrations to affect stomatal aperture, and both ABA and stoma size are affected in CAPPs stimulation of Arabidopsis seedling growth.

Efficacy of annual zoledronic acid in initial percutaneous kyphoplasty patients with osteoporotic vertebral compression fractures: a 3-year follow-up study

This study investigated the efficacy of annual zoledronic acid (ZOL) administration against previously treated recompression vertebral fractures (RVF) and new vertebral fractures (NVF) in initial percutaneous kyphoplasty (PKP) patients with osteoporotic vertebral compression fractures (OVCF) over a 3-year follow-up period.

INTRODUCTION

Although PKP achieves a satisfactory outcome, previously treated RVF and NVF can limit its effectiveness. The annual infusion of ZOL over 3 years can improve fracture protection, particularly in the vertebrae. We hypothesized that ZOL can reduce the incidence of RVFs and/or NVFs, and improve the clinical outcomes of PKP.

METHODS

This was a placebo-controlled, double-blind prospective trial of 154 PKP patients (mean age: 70 years) with OVCFs. Patients were randomly assigned to receive a single infusion of ZOL (5 mg) or placebo (78 ZOL vs. 76 placebo) at 1 week, 12 months, and 24 months after surgery. Patients were followed-up for 36 months.

RESULTS

ZOL treatment lowered the risk of RVF by ~ 65% over the 36-month period when compared to placebo controls (6.41% in ZOL vs. 18.42% in placebo groups; relative risk, 0.35; 95% CI, 0.13 to 0.92). ZOL also reduced the risk of NVF by ~ 73% (3.85% in ZOL vs. 14.47% in placebo groups; relative risk, 0.27; 95% CI, 0.08 to 0.92). ZOL also significantly reduced the vertebral height lost rate (HLR) at 12, 24, and 36 months. ZOL also improved the visual analog scale (VAS), Oswestry disability index (ODI) scores, and bone mineral density (BMD).

CONCLUSION

Annual ZOL administration significantly lowers the risk of RVFs and NVFs, improving the clinical outcome of initial PKP in patients with OVCFs over a 3-year follow-up period.

TRIAL REGISTRATION

ChiCTR2000029307.

Transcriptome analysis reveals the effect of high-grain pelleted and non-pelleted diets on ruminal epithelium of Hu-lamb

High-grain non-pelleted (HG) and high-grain pelleted (HP) diets are becoming prevalent for ruminant feeding in intensive farms. However, rare information is about their effect on sheep and the comparison between these two kinds of diets. The current study investigated how HG and HP diets affected the transcriptome profiles of rumen epithelium in Hu-lamb. Fifteen male Hu-lambs were assigned randomly to three groups (n = 5 for each group). Lambs in the control (CON), HG, and HP groups were fed with low-grain non-pelleted diet (30% grain), HG diet (70% grain), and HP diet (70% grain), respectively, for 42 days. All these lambs were slaughtered to collect ruminal epithelium samples for transcriptome analysis. Results showed both HG and HP diets obviously changed the transcriptome profiles, and 192, 319, and three differentially expressed genes (DEGs) were identified for CON_HG, CON_HP, and HG_HP comparisons, respectively. Clusters of orthologous group functional classification of CON_HG and CON_HP DEG datasets both showed the enrichments of DEGs in pathways involved in protein biogenesis and modification as well as energy production and conversion. Kyoto encyclopedia of genes and genomes pathway analysis of CON_HG and CON_HP DEG datasets both displayed the enrichments of DEGs in ribosome and oxidative phosphorylation. Almost all these DEGs involved in translation and ribosomal structure and biogenesis as well as oxidative phosphorylation were downregulated in the HG and HP groups compared to the CON group. Furthermore, CON_HP comparison demonstrated more DEGs related to these two pathways than CON_HG comparison. In conclusion, both HG and HP diets inhibited energy production and conversion as well as protein synthesis and modification in ruminal epithelium. HP diet showed lower growth benefits, induced severer rumen acidosis, and more seriously inhibited energy production and protein synthesis as compared to HG diet.

Spontaneous Enhanced Visible-Light-Driven Photocatalytic Water Splitting on Novel Type-II GaSe/CN and Ga2SSe/CN vdW Heterostructures

With the aggravation of environmental pollution and the energy crisis, it is particularly important to develop and design environment-friendly and efficient spontaneous enhanced visible-light-driven photocatalysts for water splitting. Herein novel type-II van der Waals (vdW) GaSe/CN and Ga₂SSe/CN heterostructures are proposed through first-principles calculations. Their electronic properties and photocatalytic performance are theoretically analyzed. In particular, their appropriate band gap and band-edge position meet the requirements of the oxygen evolution reaction, and the reaction is thermodynamically feasible in most pH ranges. The unique band alignment of these heterostructured photocatalysts leads to high solar-to-hydrogen energy conversion efficiencies up to 15.11%, which has a good commercial application prospect. More excitingly, with the application of 2% biaxial strain, the smooth progress of the water-splitting reaction of the GaSe/CN and Ga₂SSe/CN heterostructures can still be maintained, and the carrier mobility and optical absorption characteristics can be effectively improved. Consequently, these findings suggest that the GaSe/CN and Ga₂SSe/CN vdW heterostructures have promising potentials as photocatalysts for water splitting. This work may provide a promising clue for the design of efficient and stable photocatalytic water-splitting catalysts under visible spectroscopy.

The mycobacterial proteasomal ATPase Mpa forms a gapped ring to engage the 20S proteasome

Although many bacterial species do not possess proteasome systems, the actinobacteria, including the human pathogen Mycobacterium tuberculosis, use proteasome systems for targeted protein removal. Previous structural analyses of the mycobacterial proteasome ATPase Mpa revealed a general structural conservation with the archaeal proteasome-activating nucleotidase and eukaryotic proteasomal Rpt1–6 ATPases, such as the N-terminal coiled-coil domain, oligosaccharide-/oligonucleotide-binding domain, and ATPase domain. However, Mpa has a unique β-grasp domain that in the ADP-bound crystal structure appears to interfere with the docking to the 20S proteasome core particle (CP). Thus, it is unclear how Mpa binds to proteasome CPs. In this report, we show by cryo-EM that the Mpa hexamer in the presence of a degradation substrate and ATP forms a gapped ring, with two of its six ATPase domains being highly flexible. We found that the linkers between the oligonucleotide-binding and ATPase domains undergo conformational changes that are important for function, revealing a previously unappreciated role of the linker region in ATP hydrolysis–driven protein unfolding. We propose that this gapped ring configuration is an intermediate state that helps rearrange its β-grasp domains and activating C termini to facilitate engagement with proteasome CPs. This work provides new insights into the crucial process of how an ATPase interacts with a bacterial proteasome protease.

Structural basis for aggregate dissolution and refolding by the Mycobacterium tuberculosis ClpB-DnaK bi-chaperone system

The M. tuberculosis (Mtb) ClpB is a protein disaggregase that helps to rejuvenate the bacterial cell. DnaK is a protein foldase that can function alone, but it can also bind to the ClpB hexamer to physically couple protein disaggregation with protein refolding, although the molecular mechanism is not well understood. Here, we report the cryo-EM analysis of the Mtb ClpB-DnaK bi-chaperone in the presence of ATPγS and a protein substrate. We observe three ClpB conformations in the presence of DnaK, identify a conserved TGIP loop linking the oligonucleotide/oligosaccharide-binding domain and the nucleotide-binding domain that is important for ClpB function, derive the interface between the regulatory middle domain of the ClpB and the DnaK nucleotide-binding domain, and find that DnaK binding stabilizes, but does not bend or tilt, the ClpB middle domain. We propose a model for the synergistic actions of aggregate dissolution and refolding by the Mtb ClpB-DnaK bi-chaperone system.

Yin et al. use cryo-EM to analyze the structure of the Mycobacterium tuberculosis ClpB-DnaK bi-chaperone system. They find that the Mtb ClpB middle domain does not bend or tilt when interacting with DnaK. They therefore propose that the Mtb DnaK facilitates protein folding following protein disaggregation by ClpB.

[Risk factors for mortality in pediatric acute respiratory distress syndrome requiring extracorporeal membrane oxygenation support]

Objective: To explore the risk factors for mortality in pediatric acute respiratory distress syndrome (PARDS) requiring extracorporeal membrane oxygenation (ECMO) support. Methods: Clinical data of 109 patients with severe PARDS supported by ECMO, who were hospitalized in 6 ECMO centers in China from September 2012 to February 2020, were retrospectively analyzed. They were divided into survival group and death group according to the prognosis. Chi-square test and rank sum test were used to compare the variables between the two groups, including the demographic data, laboratory examination results, clinical data before and after ECMO, and other supportive treatment. Univariate and multivariate Logistic regression models were used to analyze the prognostic risk factors. Results: In these 109 cases, 54 died and 55 survived. Compared with the survival group, the death group had higher incidences of acute kidney injury (AKI) (48.1% (26/54) vs. 21.8% (12/55), χ²=8.318, P=0.004) and coagulation dysfunction (22.2% (12/54) vs. 7.3% (4/55), χ²=4.862, P=0.027), and higher rate of renal replacement therapy (48.1% (26/54) vs. 21.8% (12/55), χ²=9.694, P=0.008) during ECMO support. Logistic regression analysis showed that continuous renal replacement therapy (CRRT) and AKI were independent risk factors for death in patients with severe PARDS requiring ECMO support (HR=3.88,95%CI 1.04-14.52, HR=4.84,95%CI 1.21-19.46, both P<0.05). Conclusion: AKI and CRRT are independent risk factors for predicting mortality in patients with severe PARDS requiring ECMO support.

Au101-rGO nanocomposite: immobilization of phosphine-protected gold nanoclusters on reduced graphene oxide without aggregation

Graphene supported transition metal clusters are of great interest for potential applications, such as catalysis, due to their unique properties. In this work, a simple approach to deposit Au₁₀₁(PPh₃)₂₁Cl₅ (Au₁₀₁NC) on reduced graphene oxide (rGO) via an ex situ method is presented. Reduction of graphene oxide at native pH (pH ≈ 2) to rGO was performed under aqueous hydrothermal conditions. Decoration of rGO sheets with controlled content of 5 wt% Au was accomplished using only pre-synthesised Au₁₀₁NC and rGO as precursors and methanol as solvent. High resolution scanning transmission electron microscopy indicated that the cluster size did not change upon deposition with an average diameter of 1.4 ± 0.4 nm. It was determined that the rGO reduction method was crucial to avoid agglomeration, with rGO reduced at pH ≈ 11 resulting in agglomeration. X-ray photoelectron spectroscopy was used to confirm the deposition of Au₁₀₁NCs and show the presence of triphenyl phosphine ligands, which together with attenuated total reflectance Fourier transform infrared spectroscopy, advocates that the deposition of Au₁₀₁NCs onto the surface of rGO was facilitated via non-covalent interactions with the phenyl groups of the ligands. Inductively coupled plasma mass spectrometry and thermogravimetric analysis were used to determine the gold loading and both agree with a gold loading of ca. 4.8-5 wt%. The presented simple and mild strategy demonstrates that good compatibility between size-specific phosphine protected gold clusters and rGO can prevent aggregation of the metal clusters. This work contributes towards producing an agglomeration-free synthesis of size-specific ligated gold clusters on rGO that could have wide range of applications.

A supersonic laser ablation beam source with narrow velocity spreads

A supersonic beam source for SrF and BaF molecules is constructed by combining the expansion of carrier gas (a mixture of 2% SF₆ and 98% argon) from an Even-Lavie valve with laser ablation of a barium/strontium metal target at a repetition rate of 10 Hz. Molecular beams with a narrow translational velocity spread are produced at relative values of Δv/v = 0.053(11) and 0.054(9) for SrF and BaF, respectively. The relative velocity spread of the beams produced in our source is lower in comparison with the results from other metal fluoride beams produced in supersonic laser ablation sources. The rotational temperature of BaF is measured to be 3.5 K. The source produces 6 × 10⁸ and 10⁷ molecules per steradian per pulse in the X²Σ⁺ (ν = 0, N = 1) state of BaF and SrF molecules, respectively, a state amenable to Stark deceleration and laser cooling.

[Role of 1, 25-dihydroxyvitamin D3 in liver lipid metabolism induced by methionine-choline-deficient diet in rats]

Objective: To investigate the role of 1, 25-dihydroxyvitamin D3 [1.25(OH) (2)D(3)] in liver lipid metabolism so as to provide the clues for elucidating the mechanism of non-alcoholic fatty liver. Methods: 26 SD rats were randomly divided into control group (methionine-choline-sufficient diet, MCS), model group (methionine-choline-deficiency diet, MCD) and intervention group [MCD+1.25(OH) (2)D(3)]. The intervention, control, and model group was given 3 ng/100 g 1.25(OH) (2)D(3) peanut oil solution per day by gavage according to body mass. After 4 weeks the experiment was ended up, and the blood was collected from the inferior vena cava to detect alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The liver tissue was collected to observe the liver morphological and pathological changes (oil red O and HE staining). The changes in the level of liver total triglyceride (TG) content and liver lipid metabolism-related genes [fatty acid transfer protein (FAT/CD36), acetyl-coenzyme A carboxylase (ACC1)] mRNA and protein were detected. One-way analysis of variance was used to compare the means between groups. Results: Oil red O staining and HE staining showed that lipid droplet-vacuoles were significantly increased in the liver tissue of the model group than that of the intervention group. The liver TG content (2.23 ± 0.98) μmol/g of the intervention group was significantly lower than that of the model group (3.53 ± 1.06) μmol/g (F = 5.930, P = 0.035). The ALT content of the intervention group (35.99±9.54) U/L was significantly lower than that of the model group (57.65 ± 19.42) U/L (F = 13.790, P = 0.034). The AST content of the intervention group (16.9 ± 3.73) U/L was significantly lower than that of the model group (27.81 ± 13.31) U/L (F = 3.084, P = 0.046). The relative expression levels of mRNA and protein (mRNA: 1.21 ± 0.61, protein: 1.54 ± 0.75) of FAT/CD36 in the intervention group were significantly lower than those of the model group (mRNA: 2.31 ± 0.81, protein: 2.83 ± 1.42) (mRNA: F = 8.370, P = 0.001, protein: F = 7.212, P = 0.043). The relative expression level of mRNA and protein of ACC1 (mRNA: 0.89 ± 0.54, protein: 0.28 ± 0.11) were also significantly lower than those in model group (mRNA: 1.39 ± 0.19, protein: 0.47 ± 0.24) (mRNA: F = 3.948, P = 0.036, protein: F = 10.933, P = 0.048). Conclusion: 1.25(OH) (2)D(3) can reduce liver fat deposition in rats fed with MCD by inhibiting the expression of fat / CD36 and ACC1.

Carbonisation of a polymer made from sulfur and canola oil

A polymer made from sulfur and canola oil can be used as an oil spill sorbent and then repurposed into a sulfur-rich graphitic carbon for mercury removal from water.

Highly Stable Indacenodithieno[3,2-b]thiophene-Based Donor-Acceptor Copolymers for Hybrid Electrochromic and Energy Storage Applications

Stable doping of indacenodithieno[3,2-b]thiophene (IDTT) structures enables easy color tuning and significant improvement in the charge storage capacity of electrochromic polymers, making use of their full potential as electrochromic supercapacitors and in other emerging hybrid applications. Here, the IDTT structure is copolymerized with four different donor-acceptor-donor (DAD) units, with subtle changes in their electron-donating and electron-withdrawing characters, so as to obtain four different donor-acceptor copolymers. The polymers attain important form factor requirements for electrochromic supercapacitors: desired switching between achromatic black and transparent states (L*a*b* 45.9, -3.1, -4.2/86.7, -2.2, and -2.7 for PIDTT-TBT), high optical contrast (72% for PIDTT-TBzT), and excellent electrochemical redox stability (Ired/Iox ca. 1.0 for PIDTT-EBE). Poly[indacenodithieno[3,2-b]thiophene-2,8-diyl-alt-4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-(2-hexyldecyl)-2H-benzo[d][1,2,3]triazole-7,7'-diyl] (PIDTT-EBzE) stands out as delivering simultaneously a high contrast (69%) and doping level (>100%) and specific capacitance (260 F g-1). This work introduces IDTT-based polymers as bifunctional electro-optical materials for potential use in color-tailored, color-indicating, and self-regulating smart energy systems.

[Research progress on application of laboratory indicators detection of COVID-19]

The outbreak of corona virus disease-19 (corona virus disease-19, COVID-19) caused a huge human disaster from the end of 2019 which is caused by SARS-CoV-2. It will cause damage to multiple organs function in the disease occurrence and development, viral nucleic acid, antibody and serological biochemical immune indicators are mainly indicators of clinical laboratory. The results of these indicators can reflect the organs function of patients and further guide clinical treatment. In this paper, the detection and clinical application of COVID-19 laboratory indicators are reviewed.

In Situ Formation of Mixed-Dimensional Surface Passivation Layers in Perovskite Solar Cells with Dual-Isomer Alkylammonium Cations

Dimensional engineering of perovskite solar cells has attracted significant research attention recently because of the potential to improve both device performance and stability. Here, a novel 2D passivation scheme for 3D perovskite solar cells is demonstrated using a mixed cation composition of 2D perovskite based on two different isomers of butylammonium iodide. The dual-cation 2D perovskite outperforms its single cation 2D counterparts in surface passivation quality, resulting in devices with an impressive open-circuit voltage of 1.21 V for a perovskite composition with an optical bandgap of ≈1.6 eV, and a champion efficiency of 23.27%. Using a combination of surface elemental analysis and valence electron spectra decomposition, it is shown that an in situ interaction between the 2D perovskite precursor and the 3D active layer results in surface intermixing of 3D and 2D perovskite phases, providing an effective combination of defect passivation and enhanced charge transfer, despite the semi-insulating nature of the 2D perovskite phase. The demonstration of the synergistic interaction of multiple organic spacer cations in a 2D passivation layer offers new opportunities for further enhancement of device performance with mixed dimensional perovskite solar cells.

Efficacy of utidelone plus capecitabine versus capecitabine for heavily pretreated, anthracycline- and taxane-refractory metastatic breast cancer: final analysis of overall survival in a phase III randomised controlled trial

BACKGROUND

Primary analysis of the phase III trial BG01-1323L demonstrated that utidelone plus capecitabine significantly improved progression-free survival (PFS) and overall response rate (ORR) versus capecitabine alone in heavily-pretreated patients with metastatic breast cancer (MBC). Here, we report the final overall survival (OS) analysis and updates of other endpoints.

PATIENTS AND METHODS

In total, 405 patients were randomised 2:1 to receive utidelone (30 mg/m² IV daily, days 1-5, over 90 min) plus capecitabine (1000 mg/m² orally b.i.d., days 1-14) or capecitabine alone (1250 mg/m² orally b.i.d., days 1-14) every 21 days. The secondary endpoint, OS, was estimated using the Kaplan-Meier product-limit approach at a two-sided alpha level of 0.05 after the prespecified 310 death events had been reached. Exploratory analyses of the primary endpoint, PFS, and the secondary endpoint, ORR, were also done. Safety was analysed in patients who had at least one dose of study drug.

RESULTS

At the final OS analysis, the median duration of follow-up was 19.6 months in the utidelone plus capecitabine group and 15.4 months in the capecitabine alone group. In the intention-to-treat population, 313 deaths had occurred at data cut-off, 203 of 270 patients in the combination group and 110 of 135 in the monotherapy group. Median OS in the combination group was 19.8 months compared with 16.0 months in the monotherapy group [hazard ratio (HR) = 0.75, 95% confidence intervals (CI) 0.59-0.94, P = 0.0142]. The updated analysis of PFS and ORR showed that the combination therapy remained superior to monotherapy. Safety results were similar to those previously reported with respect to incidence, severity and specificity. No late-emerging toxicities or new safety concerns occurred.

CONCLUSIONS

For heavily-pretreated, anthracycline- and taxane-resistant MBC patients, utidelone plus capecitabine significantly improved OS versus capecitabine alone. These results support the use of utidelone plus capecitabine as a novel therapeutic regimen for patients with MBC.