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Iron tetraphenylporphyrin complex modified with four trimethylammonium groups (Fe-p-TMA) is found to be capable of catalyzing the eight-electron eight-proton reduction of CO2to CH4photochemically in acetonitrile. In the present work, density functional theory (DFT) calculations have been performed to investigate the reaction mechanism and to rationalize the product selectivity. Our results revealed that the initial catalyst Fe-p-TMA ([Cl–Fe(III)-LR4]4+, where L = tetraphenylporphyrin ligand with a total charge of −2, and R4= four trimethylammonium groups with a total charge of +4) undergoes three reduction steps, accompanied by the dissociation of the chloride ion to form [Fe(II)-L••2–R4]2+. [Fe(II)-L••2–R4]2+, bearing a Fe(II) center ferromagnetically coupled with a tetraphenylporphyrin diradical, performs a nucleophilic attack on CO2to produce the 1η-CO2adduct [CO2•––Fe(II)-L•–R4]2+. Two intermolecular proton transfer steps then take place at the CO2moiety of [CO2•––Fe(II)-L•–R4]2+, resulting in the cleavage of the C–O bond and the formation of the critical intermediate [Fe(II)–CO]4+after releasing a water molecule. Subsequently, [Fe(II)–CO]4+accepts three electrons and one proton to generate [CHO–Fe(II)-L•–R4]2+, which finally undergoes a successive four-electron-five-proton reduction to produce methane without forming formaldehyde, methanol, or formate. Notably, the redox non-innocent tetraphenylporphyrin ligand was found to play an important role in CO2reduction since it could accept and transfer electron(s) during catalysis, thus keeping the ferrous ion at a relatively high oxidation state. Hydrogen evolution reaction via the formation of Fe-hydride ([Fe(II)–H]3+) turns out to endure a higher total barrier than the CO2reduction reaction, therefore providing a reasonable explanation for the origin of the product selectivity.

The development of novel systems for the polyoxometalate–organic cage (POC) is an attractive research field for their fascinating topological structures and well-defined functional cavities. Here, we report the successful self-assembly of anionic POC architectures {XW9Ni6L3}4(X = Si or P and L = p-aminobenzoic acid), comprising Ni6-substituted trivacant lacunary polyoxometalate (POM) and the organic ligand with both rigid COOH and flexible coordination NH2groups. It is worth noting a Keggin {XW12} (X = Si or P) in the interior cavity, which is not encountered in reported POCs. More remarkably, in the cage architecture, the chiral C3conformation was generated based on asymmetric coordination arrangement of ligands, which results in the deviation of the polyhedra and the helical arrangement of the ligands and finally constitutes the hierarchical chirality of the {POM4L12} cages. The solution stability, magnetic behavior, and dye adsorption of {SiW12}@{SiW9Ni6L3}4have also been investigated.

Inspired by OxdA that operates biocatalytic aldoxime dehydration, we have developed an efficient iron catalyst, Cp*Fe(1,2-Cy2PC6H4O) (1), which rapidly converts various aliphatic and aromatic aldoximes to nitriles with release of H2O at room temperature. The catalysis involves redox activation of the N–O bond by a 1e–transfer from the iron catalyst to the oxime. Such redox-mediated N–O cleavage was demonstrated by the isolation of a ferrous iminato intermediate from the reaction of the ketoxime substrate. This iron-catalyzed acceptorless dehydration approach represents a general method for the preparation of nitriles, and it also delivers salicylonitriles by catalyzing the Kemp elimination reaction.

ABSTRACTGlucose fluctuation is more harmful than sustained hyperglycemia, but the effect on cardiomyocyte apoptosis have not yet been clarified. In this study, we aim to identify the effect of glucose fluctuation on cardiomyocyte apoptosis and explore the underlying mechanism. Sprague-Dawley rats were intraperitoneally injected with streptozotocin (STZ) and divided into three groups: controlled diabetic group (C-STZ); uncontrolled diabetic group (U-STZ) and glucose fluctuated diabetic group (GF-STZ). After twelve weeks, echocardiography, Hematoxylin-eosin (HE) staining, and Masson staining were adopted to assess the cardiac function and pathological changes. TUNEL staining was used to detect apoptotic cells. Expressions of apoptosis-related proteins and key molecules in the endoplasmic reticulum (ER) stress pathway were determined via western blots. Further, primary cardiomyocytes incubated in different glucose conditions were treated with the inhibitor of ER stress to explore the causative role of ER stress in glucose fluctuation-induced cardiomyocyte apoptosis. In vivo, we demonstrated that glucose fluctuation promoted cardiomyocyte apoptosis, and were more harmful to cardiomyocytes than sustained hyperglycemia. Moreover, glucose fluctuation significantly triggered ER stress signaling pathway. In vitro, primary cardiomyocyte apoptosis induced by glucose fluctuation and the activation of ER stress were significantly attenuated by 4-PBA, which is an ER stress inhibitor. Above all, glucose fluctuation can promote cardiomyocyte apoptosis through triggering the ER stress signaling pathway in diabetic rats and in primary cardiomyocytes.

Parent amido complexes are crucial intermediates in ammonia-based transformations. We report a well-defined ferric ammine system [Cp*Fe(1,2-Ph2PC6H4NH)(NH3)]+([1-NH3]+), which processes electrocatalytic ammonia oxidation to N2and H2at a mild potential. Through establishing elementary e–/H+conversions with the ferric ammine, a formal Fe(IV)-amido species, [1-NH2]+, together with its conjugated Lewis acid, [1-NH3]2+, was isolated and structurally characterized for the first time. Mechanism studies indicated that further oxidation of [1-NH2]+induces the reaction of the parent amido unit with NH3. The formation of hydrazine is realized by the non-innocent nature of the phenylamido ligand that facilitates the concerted transfer of one proton and two electrons.

Proton radiotherapy may be a compelling technical option for the treatment of breast cancer due to its unique physical property known as the “Bragg peak.” This feature offers distinct advantages, promising superior dose conformity within the tumor area and reduced radiation exposure to surrounding healthy tissues, enhancing the potential for better treatment outcomes. However, proton therapy is accompanied by inherent challenges, primarily higher costs and limited accessibility when compared to well-developed photon irradiation. Thus, in clinical practice, it is important for radiation oncologists to carefully select patients before recommendation of proton therapy to ensure the transformation of dosimetric benefits into tangible clinical benefits. Yet, the optimal indications for proton therapy in breast cancer patients remain uncertain. While there is no widely recognized methodology for patient selection, numerous attempts have been made in this direction. In this review, we intended to present an inspiring summarization and discussion about the current practices and exploration on the approaches of this treatment decision-making process in terms of treatment-related side-effects, tumor control, and cost-efficiency, including the normal tissue complication probability (NTCP) model, the tumor control probability (TCP) model, genomic biomarkers, cost-effectiveness analyses (CEAs), and so on. Additionally, we conducted an evaluation of the eligibility criteria in ongoing randomized controlled trials and analyzed their reference value in patient selection. We evaluated the pros and cons of various potential patient selection approaches and proposed possible directions for further optimization and exploration. In summary, while proton therapy holds significant promise in breast cancer treatment, its integration into clinical practice calls for a thoughtful, evidence-driven strategy. By continuously refining the patient selection criteria, we can harness the full potential of proton radiotherapy while ensuring maximum benefit for breast cancer patients.

Metal–organic frameworks (MOFs) or coordination polymers (CPs)-based phosphorescence materials may provide a powerful route for photoelectric and optical recording devices. Herein, two phosphorescence ligands, iso-phthalic acid (IPA) and 2-methylimidazole (MIM), were selected to construct an nonporous CP {Zn(IPA)(MIM)2} (1) with a long-lived phosphorescence lifetime up to 552 ms. By the doping of Eosin Y (EY) dye molecules under an in situ process, the phosphorescence emission color of 1can be expressly tuned from green to red. The light-harvesting range can also be vastly broadened from the UV to the visible region (550 nm). Photoelectron measurements reveal that the synergistic effect of bias voltage and illumination can greatly restrain electron–hole recombination for the generation of additional free charges.

A highly efficient approach of visible-light-driven radical difluoromethylation of isocyanides to access a wide variety of difluoromethylated phenanthridines and isoquinolines is herein described. Electrophilic S-(difluoromethyl)diarylsulfonium salt proved to be a good difluoromethyl radical precursor under photoredox catalysis. A broad range of isocyanides were tolerated to furnish the corresponding difluoromethylated phenanthridines, isoquinolines, furo[3,2-c]pyridine, and pyrido[3,4-b]indole in moderate to excellent yields under mild conditions. A plausible mechanism was also proposed.

We describe the cobalt(II) catalyst 1bearing a phosphinopyridonate ligand for sequential transformation of aryl terminal alkynes to (E,Z)-1,3-dienes with excellent stereoselectivity. By cooperative metal–ligand reactivity, 1reacts readily with the terminal alkynes to afford the alkynyl cobalt intermediate for dimerization, producing (E)-1,3-enynes, and then to smoothly catalyze reduction of the acetylene unit to the olefin by H3N·BH3. A plausible catalytic cycle for both dimerization and transfer hydrogenation was proposed on the basis of stoichiometric reactions and DFT calculations, which suggest the ability of the cobalt catalyst to activate the amine–borane as well as the terminal alkyne through cobalt pyridonate cooperation.

Iron complex Cp*(Ph2PC6H4S)Fe was recently reported to regioselectively catalyze the hydroboration of N-heteroarenes with pinacolborane (HBpin). Density functional calculations were performed to elucidate the reaction mechanism and to rationalize the regioselectivity. Three different reaction pathways were considered, and the hydrogen atom transfer pathway was found to be the most favorable one. The reaction started with a hydrogen atom transfer from pyridine–HBpin complex to the metal center of the catalyst. This leads to the generation of a pyridine–Bpin radical and an iron(III)-hydride intermediate. Then, the hydrogen atom can be transferred to either ortho- or para-position of the borylated N-heteroarenes, affording the corresponding products. The origin of the regioselectivity was found to be interaction-controlled from distortion/interaction analysis. The suggested mechanism can rationalize very well the regioselectivity of all other N-heteroarene substrate.

A facile and highly efficient approach for selective O-difluoromethylation of 1,3-diones with S-(difluoromethyl)sulfonium salt was developed, and a wide variety of difluoromethyl enol ethers were readily synthesized.

Exploring bidirectional CO2/HCO2–catalysis holds significant potential in constructing integrated (photo)electrochemical formate fuel cells for energy storage and applications. Herein, we report selective CO2/HCO2–electrochemical interconversion by exploiting the flexible coordination modes and rich redox properties of a versatile iron-thiolate platform, Cp*Fe(II)L (L = 1,2-Ph2PC6H4S–). Upon oxidation, this iron complex undergoes formate binding to generate a diferric formate complex, [(L–)2Fe(III)(μ-HCO2)Fe(III)]+, which exhibits remarkable electrocatalytic performance for the HCO2–-to-CO2transformation with a maximum turnover frequency (TOFmax) ∼103s–1and a Faraday efficiency (FE) ∼92(±4)%. Conversely, this iron system also allows for reduction at −1.85 V (vs Fc+/0) and exhibits an impressive FE ∼93 (±3)% for the CO2-to-HCO2–conversion. Mechanism studies revealed that the HCO2–-to-CO2electrocatalysis passes through dicationic [(L2)−•Fe(III)(μ-HCO2)Fe(III)]2+generated by unconventional oxidation of the diferric formate species taking place at ligand L, while the CO2-to-HCO2–reduction involves a critical intermediate of [Fe(II)-H]−that was independently synthesized and structurally characterized.

Equisetumfossils are often reported from the Cenozoic strata in the Northern Hemisphere, but their occurrence in the Qinghai-Tibetan Plateau (QTP) region is scarce. In this investigation, two new species of tuber fossils of Equisetum— Equisetum wulanenseZhang and Xie, n. sp. and Equisetum kekeenseZhang and Xie, n. sp. from the Miocene Youshashan Formation of the Wulan Basin, Qinghai Province are reported. The extant Equisetumplants are usually living in wet habitats. Therefore, fossil species, E. wulanenseand E. kekeense, were likely to live in moist environments during Miocene too. The discovery of E. wulanenseand E. kekeensein the late Middle Miocene (∼13.4 Ma) indicates that the local climate of the Wulan Basin was more favorable during this period. This new finding confirmed the previous view that the Neogene aridification in the northern QTP was varying: the climate in the Early Miocene and the Middle Miocene were relatively warm and humid and then the climate gradually became colder and drier since the Late Miocene. It is widely accepted that the uplift of the QTP intensified the trend of cooling and drying since the Late Miocene, and eventually formed a cold and dry climate pattern in the northeast margin of the QTP. The discovery of Equisetumfossils in this investigation improved our understanding on the Cenozoic diversity of Equisetumplants in the northern QTP, as well as on the paleoecological environments of the Wulan Basin in Miocene.

Considering the corrosion degree of reinforcement, the chloride penetration resistance of concrete and chloride concentration distribution in concrete, a health evaluation method for durability of harbor engineering was established by analytic hierarchy process (AHP). Analysis of a harbor in South China demonstrates that the health indicator for durability condition of existing structures can be effectively used to quantitatively health evaluation for durability of practical engineering.

The first-principles with pseudopotentials method based on the density functional theory was applied to calculate the geometric structure, the formation energy of impurities and the electronic structure of Li-doped ZnO. In the system of Li-doped ZnO, LiZn can not result in lattice distortion. In contrast with that case, LiO and Lii result in lattice distortion after Li doping in ZnO. In Li-doped ZnO, LiO is the most unstable than the other cases. Simultaneously, Lii is more stable than LiZn according to that Lii has smaller formation energy. Furthermore, the electronic structure of Li-doped ZnO indicates that that LiZn behaves as acceptor, while Lii behaves as donor. In conclusion, in Li-doped ZnO, Lii is always in the system to compensate the acceptor. Singly doping Li in ZnO is difficult to gain p-ZnO for the self-compensation. The results are in good agreement with other calculated and experimental results.

This research works for plain stitch of weft knitted stitch, mainly introduced the curling property of plain stitch and it’s influence factors were given. I will combine with plain stitch's structure characteristics and its unique fringe curling of style to design and produce suitable knitwear to satisfy the increasing needs of ourselves in the modern life. Drape, three dimentional cutting, also means stereo cutting, was taken to the research in order to design and make a middle and long tape skirt with black and gray, together with a white super short T-shirt, we can see the application of fringe culing in the collar, bottom margin, wristband and so on. In short, color in harmony, long and short matching brings to harmonious with nature.

The LED illumination has extremely high luminous efficiency, which is5 or 10 times of incandescent, 2 times of the traditional energy-saving lamps and 1.5 times of high-pressure sodium lamp. It has been widely used in the lamp products of lighting and decoration. At present, the biggest problem that the LED lighting products facing is the stability and reliability of LED drive circuit. The paper tries to explore the scientific and technical standards and test schemes of LED drive technology parameters, which has a certain significance of improving reliability and safety of LED lighting technology.

OsSUT2encodes a putative sucrose transporter containing 12 transmembrane domains in rice plants. Subcellular localization of the OsSUT2::GFP fusion protein indicated that OsSUT2 is a cell membrane protein. In embryos of germinating seeds, the expression of OsSUT2gradually increased during the early germinating stage. The developmental regulations of OsSUT2in germinating embryos could be mediated by sugars transported from endosperms. OsSUT2expression was up-regulated by glucose through a hexokinase-independent pathway. Exogenous sucrose was sensed by a sensor localized on the plasma membrane and functioned as an enhancer to promote OsSUT2expression. Based on OsSUT2promoter::GUSexpression in germinating seeds of transgenic rice, OsSUT2was significantly expressed in the embryos and aleurone layers. In embryos, strong GUS expression was detected in the scutellum and vascular bundle tissues. Developmental stage- and sugar-dependent OsSUT2expression was suggested to be controlled by transcriptional regulation of the promoter region.

A set of deterministic and probabilistic models for estimating the accident washout factor are developed and established based on accident dispersion factor models given by current guidelines. The deterministic washout factor for different time intervals after accident release, the probabilistic washout factor, and the dose corresponding to various pathways are estimated based on the measured meteorological data on the site of a coastal nuclear power plant to be built in the southeastern part of China. The results show that for doses obtained from 0 to 8 h after a design-basis accident release, the external exposure dose from washout deposition given by the deterministic model is ~55% of that from dry deposition and 22% of individual effective dose (except wet deposition dose); the ratios of external exposure dose from washout to that from dry deposition and to effective dose (except wet deposition dose) given by the probabilistic model are ~5.73 and 2.29, respectively.

Objective.The aim of this study was to determine whether the activity of topoisomerase I (topo I), the target of the anti-neoplastic drug camptothecin (CPT), is elevated in cervical cancer and whether CPT can radiosensitize cervical tumors.

Phytate as a root exudate is rare in plants as it mainly serves as a P storage in the seeds; however, As-hyperaccumulator Pteris vittataeffectively secretes phytate and utilizes phytate-P, especially under As exposure. This study investigated the effects of As on its phytate and phytase exudation and the impacts of As and/or phytate on each other’s uptake in P. vittatathrough two hydroponic experiments. Under 10–100 μM arsenate (AsV), the exudation of phytate and phytase by P. vittatawas increased by 50–72% to 20.4–23.4 μmol h–1g–1and by 28–104% to 18.6–29.5 nmol h–1plant–1, but they were undetected in non-hyperaccumulator Pteris ensiformisat 10 μM AsV. Furthermore, compared to 500 μM phytate, the phytate concentration in the growth media was reduced by 69% to 155 μM, whereas the P and As contents in P. vittatafronds and roots were enhanced by 68–134% and 44–81% to 2423–2954 and 82–407 mg kg–1under 500 μM phytate plus 50 μM AsV. The increased P/As uptake in P. vittatawas probably attributed to 3.0–4.5-fold increase in expressions of P transporters PvPht1;3–1;4. Besides, under As exposure, plant P may be converted to phytate in P. vittataroots, thereby increasing phytate’s contents by 84% to 840 mg kg–1. Overall, our results suggest that As-induced phytate/phytase exudation and phytate-P uptake stimulate its growth and As hyperaccumulation by P. vittata.

Selenate enhances arsenic (As) accumulation in As-hyperaccumulator Pteris vittata, but the associated molecular mechanisms are unclear. Here, we investigated the mechanisms of selenate-induced arsenic accumulation by exposing P. vittatato 50 μM arsenate (AsV50) and 1.25 (Se1.25) or 5 μM (Se5) selenate in hydroponics. After 2 weeks, plant biomass, plant As and Se contents, As speciation in plant and growth media, and important genes related to As detoxification in P. vittatawere determined. These genes included P transporters PvPht1;3and PvPht1;4(AsV uptake), arsenate reductases PvHAC1and PvHAC2(AsV reduction), and arsenite (AsIII) antiporters PvACR3and PvACR3;2(AsIII translocation) in the roots, and AsIII antiporters PvACR3;1and PvACR3;3(AsIII sequestration) in the fronds. The results show that Se1.25was more effective than Se5in increasing As accumulation in both P. vittataroots and fronds, which increased by 27 and 153% to 353 and 506 mg kg–1. The As speciation analyses show that selenate increased the AsIII levels in P. vittata, with 124–282% more AsIII being translocated into the fronds. The qPCR analyses indicate that Se1.25upregulated the gene expression of PvHAC1by 1.2-fold, and PvACR3and PvACR3;2by 1.0- to 2.5-fold in the roots, and PvACR3;1and PvACR3;3by 0.6- to 1.1-fold in the fronds under AsV50treatment. Though arsenate enhanced gene expression of P transporters PvPht1;3and PvPht1;4, selenate had little effect. Our results indicate that selenate effectively increased As accumulation in P. vittata, mostly by increasing reduction of AsV to AsIII in the roots, AsIII translocation from the roots to fronds, and AsIII sequestration into the vacuoles in the fronds. The results suggest that selenate may be used to enhance phytoremediation of As-contaminated soils using P. vittata.

ABSTRACTThis study aims to identify the density of TILs in ductal carcinoma in situ (DCIS) in terms of prognostic significance with recurrence and the benefit of whole breast irradiation (WBI). The clinicopathological data of DCIS patients from Jan 2009 to Dec 2016 who received breast-conserving surgery (BCS) were retrospectively reviewed. Cox regression analysis was used to confirm independent prognostic factors of ipsilateral breast tumor recurrence (IBTR). Kaplan–Meier method was utilized to analyze IBTR and values of WBI. Touching-tumor-infiltrating lymphocytes (TILs) were defined by TILs touching or within one lymphocyte cell thickness from the malignant ducts’ basement membrane. In total, 129 patients were enrolled in this analysis with 98 patients who received WBI. After a median follow-up of 53.0 months, there were 16 IBTR events with five invasive IBTRs. Univariate and multivariate analyses showed that touching-TILs >5 were an independent prognostic factor for higher IBTR (HR = 6.17, 95%CI 1.95–19.56, p< .01). The whole cohort was classified into two subgroups: dense group (>5 touching-TILs per duct) and sparse group (≤5 touching-TILs per duct). Dense touching-TILs were associated with unfavorable biologic characteristics. The 5-y rate of IBTR between dense and sparse group was 29.0% versus 4.5% (p< .01). For the sparse group, WBI significantly reduced the rate of 5-y-IBTR risk from 13.2% to 1.7% (p= .02), but there was no benefit of WBI in the dense group. Touching-TILs density was heterogeneous in patients with DCIS. Sparse touching-TILs were associated with better prognosis and benefit from WBI. Dense touching-TILs not only were associated with a higher risk of IBTR but also lack of benefit from WBI.

C13H19N3O3, monoclinic, P21/c(no. 14), a= 11.594(5) Å, b= 11.311(5) Å, c= 11.688(5) Å, β= 117.347(19)°, V= 1361.4(10) Å3, Z= 4, Rgt(F) = 0.0479, wRref(F2) = 0.1630, T= 296 K.

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