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Patients undergoing hemodialysis are a high-risk population. This study identified possible errors by using a healthcare failure mode and effect analysis system to improve patient safety during hemodialysis.A multidisciplinary collaborative team, including physicians, nurses, information technicians, and medical staff members, was assembled. A flow diagram was used to indicate each process of the hemodialysis procedure from evaluating patient condition to transporting the patient back to the ward from the hemodialysis center. We scored all possible failure modes using the hazard scoring method as a combination of the occurrence frequency and severity. These potential failure modes were used to identify and evaluate possible risks by using a risk scoring matrix.Thirty failure modes were identified across 6 processes, and their potential causes were explored. Four major strategies for addressing most of the failure modes were implemented: establishment of a mobile application that sends real-time automated alerts to the medical team based on the Modified Early Warning Score, design of a modified dialysis Identify-Situation-Background-Assessment-Recommendation checklist for dialysis, technician education and training, and internal auditing and monitoring of the implementation of the entire process. After the implementation of the strategies, the hazard scores of patients during dialysis dropped by 71.2% from 170 points to 49 points.The healthcare failure mode and effect analysis system was useful for evaluating potential risk during dialysis. Using the mobile application reduced the occurrence of emergency resuscitation during hemodialysis and significantly improved the communication between medical personnel.

Stroke patients presenting with anemia at the time of stroke onset had a higher risk of mortality and development of other cardiovascular diseases and comorbidities. The association between the severity of anemia and the risk of developing a stroke is still uncertain. This retrospective study aimed to evaluate the association between stroke incidence and anemia severity (by WHO criteria). A total of 71,787 patients were included, of whom 16,708 (23.27%) were identified as anemic and 55,079 patients were anemia-free. Female patients (62.98%) were more likely to have anemia than males (37.02%). The likelihood of having a stroke within eight years after anemia diagnosis was calculated using Cox proportional hazard regression. Patients with moderate anemia had a significant increase in stroke risk compared to the non-anemia group in univariate analyses (hazard ratios [HR] = 2.31, 95% confidence interval [CI], 1.97–2.71, p < 0.001) and in adjusted HRs (adj-HR = 1.20, 95% CI, 1.02–1.43, p = 0.032). The data reveal that patients with severe anemia received more anemia treatment, such as blood transfusion and nutritional supplementation, and maintaining blood homeostasis may be important to preventing stroke. Anemia is an important risk factor, but other risk factors, including diabetes and hyperlipidemia, also affect stroke development. There is a heightened awareness of anemia’s severity and the increasing risk of stroke development.

Hui-Fen Chen,1 Nuo Lei,1 Yan-Min Xu,1 Li Luo,1 Xian-Long Zhang,1 Bei-Ni Lao,1 Fang Tang,2 Li-Zhe Fu,2 Xu-Sheng Liu,3 Yi-Fan Wu3 1The Second Clinical College, Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China; 2Chronic Disease Management Outpatient Clinic, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, People’s Republic of China; 3Renal Division, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, People’s Republic of ChinaCorrespondence: Yi-Fan Wu Email wuyifan007@gzucm.edu.cnBackground: To transfer a paper-version Chinese and Western medication adherence scale for CKD into an electronic scale, and evaluate its validity, internal consistency and clinical implementation, and assess whether the transition is feasible in clinic.Methods: We built an e-version Chinese and Western medication adherence scale based on the Wen-JuanXing platform. CKD subjects’ responses were applied to test the scale’s validity and internal consistency. We retested some of the participants two weeks later randomly. We also tested the clinical application.Results: Of the 434 recruited patients, 228 responded. In exploratory factor analysis (EFA), the Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy = 0.8 and Bartlett’s approx. Chi-Square = 1340.0 (df = 105, p < 0.001). We extracted four common factors which could explain 61.47% of the variance. However, Item 15 “Have you changed a traditional Chinese medicine prescription yourself within the past month?” had factor loading = 0.3 and measure of sampling adequacy (MSA) = 0.5, meaning we could not enter it into the factor analysis. The internal consistency reliability for medication adherence was 0.9, with a Guttman split-half coefficient = 0.5 and a Spearman–Brown coefficient = 0.6. Cronbach’s α was 0.9, 0.4 and 0.5 for the knowledge, belief and behavior domains, respectively. The correlation coefficient r of the test–retest reliability was − 0.8 and was − 0.8, 0.4, − 0.3 in the knowledge, belief and behavior domains, respectively. Patients with comorbidities were more likely to respond. We detected no other significant differences in the clinical profiles between respondents and non-respondents.Conclusion: The e-version Chinese and Western medication adherence scales have undesirable construct validity and internal consistency. Thus, caution is needed in transitioning the paper-version scale into an e-version.Keywords: medication adherence, renal insufficiency, chronic, surveys and questionnaires

Background Endometriosis (EM) is a benign gynecological disease that shares some characteristics with malignancy, such as proliferation and invasion. So far, the pathogenesis of EM is still unclear. In this study, we investigated whether TRIM65 can play a role in the development of EM. Methods TRIM65 expression levels in eutopic, ectopic, and normal endometrium were detected by quantitative real-time PCR and Western blot. Cell proliferation and invasion of primary endometrial stromal (EMS) cells were detected by CCK-8 and Transwell analysis. The interaction between TRIM65 and DUSP6 or C-myc was measured by coimmunoprecipitation, ubiquitylation, dual luciferase, and chromatin immunoprecipitation analysis. Results We found that TRIM65 was identified as an up-regulated gene in ectopic endometrial tissues and EMS cells compared with control groups without EM. TRIM65 expression was positively correlated with the levels of p-ERK1/2, C-myc, matrix metalloproteinase-2, and integrin β1 in ectopic endometrial tissues in patients and mice. TRIM65 promoted the cell proliferation and invasion of EMS cells via the ERK1/2/C-myc pathway through ubiquitination of DUSP6. C-myc promoted TRIM65 expression through inducing TRIM65 promoter activity. Additionally, the increased expression of TRIM65, C-myc, matrix metalloproteinase-2, integrin β1, and p-ERK1/2 and the decreased expression of DUSP6 in ectopic endometrial tissues were significantly suppressed by inhibition of ERK1/2 signaling pathway in ectopic endometrial tissues in experimental mice model. Conclusion In conclusion, TRIM65 promotes invasion of ectopic EMS cells by activating a feedback loop with the ERK1/2/C-myc signaling pathway and may be a potential therapeutic target for EM.

Background The feasibility and efficacy of low-protein diets (LPD) treatment in chronic kidney disease (CKD) is controversial. Based on the characteristics of the Chinese diet, we observe the qualification rates and short-term clinical effects of LPD for CKD patients in our center. Methods This is a retrospective cohort study. CKD stages 3–5 patients who were regularly followed up 5 times (over 2 years) and treated with LPD were included. We collected clinical data to observe the changes in LPD qualification rates and divided patients into LPD and non-LPD group according to the average dietary protein intake (DPI) of 5 follow-up time points and compared the changes in primary and secondary outcome measures between the two groups. Results We analyzed data from 161 eligible CKD stages 3–5 patients. From baseline to the 5th follow-up time point, the LPD qualification rates of all patients were 11.80%, 35.40%, 47.82%, 53.43% and 54.04%, respectively. For primary outcome measures, the urine protein/creatinine ratio (UPCR) decreased more in the LPD group than in the non-LPD group [Median (interquartile range, IQR) of the difference between the 5th follow-up time point and baseline: 0.19 (− 0.01–0.73) vs. 0.10 (− 0.08–0.27), P P P = 0.036]. For secondary outcome measures, body mass index (BMI) triglycerides (TG), body weight, and fat free mass (FFM) showed stable statistical differences in the comparison of LPD and non-LPD groups, with greater declines in the former. Conclusion The results of this study suggest that LPD treatment can reduce UPCR in patients with CKD stages 3–5, and may also delay the decline in eGFR. Meanwhile, it also reduces BMI, TG, body weight, and FFM, thus the need to prevent malnutrition in clinical implementation.

Background Chronic kidney disease (CKD) is a major global health problem. Short-term self-management has been considered to effect some renal and psychological endpoints. However, there are currently very few studies about self-management for CKD that a) have been scientifically designed by a theory-based framework and b) that evaluate the long-term effects and working mechanism. This study presents the rationale and design of a theory-based cohort study to explore how this self-management intervention works and its effectiveness on the Chinese CKD population. Methods In this ambispective intervention cohort study,1,200 patients with CKD stages 1–5 will be recruited from July 2015 to July 2024 in 3 branches of Guangdong Provincial Hospital of Chinese Medicine (GPHCM) in Guangdong province, China. The patients in the self-management cohort will choose to receive an intervention that consists of education, nutrition/diet modification, lifestyle change recommendation, medication review, and psychology support based on Social Cognition Theory (SCT). The patients in the control cohort will do regular follow-ups based on the clinic rules. All the patients will be followed up for 5 years, or until the occurrence of a primary outcome. Detailed clinical, laboratory markers, nutritional status, psychological exposures and outcome questionaries will be collected semiannually in CKD stage 1–2 and trimonthly in stage 3–5 patients. The primary outcome is the occurrence of composite clinical endpoints (doubling of serum creatinine level, ESKD, loss of renal function (≥ 40% decline in GFR from baseline), death, major cardiovascular or cerebrovascular events). The main secondary outcomes include the absolute change and slope of eGFR, absolute changes of urinary protein creatinine ratio, 24-h urine proteinuria, intact parathyroid hormone level, and self-management adherence rate and quality of life from baseline to end of the study. The effectiveness of self-management will be analyzed and the association between longitudinal trajectories of self-management and renal outcomes will be evaluated. Discussion This study aims to provide further evidence for the effectiveness of theory-based self-management in CKD patients and to improve the lives of patients with CKD by slowing progression, improving psychological well-being and overall quality of life. Trial registration Chinese Clinical Trial Register (ChiCTR1900024633). 19 July, 2019. http://www.chictr.org.cn/showproj.aspx?proj=38378

The Quzhi formula, a Chinese medicine compound prescription, relieves nonalcoholic steatohepatitis (NASH) symptoms. This study aimed to explore the mechanism of the Quzhi formula against NASH.A choline-deficient, L-amino acid-defined, high-fat diet induced a NASH mouse model and a free fatty acid-induced mouse hepatocyte cell model were used to evaluate the function of Quzhi formulaThe positive contribution of the Quzhi formula on NASH was confirmedThe Quzhi formula protected against NASH by inhibiting lipid accumulation, ER stress, and inflammatory responses, which supports the potential use of Quzhi formula as an alternative treatment for NASH.

Objective The self-reported scale is a widely used method to assess patients' medication adherence in clinical practice, but there is still a lack of medicine adherence measurement scale for patients with Chronic Kidney Disease (CKD). Therefore, this study aimed to develop a medication adherence measurement scale of traditional Chinese medicine and Western medicine, providing a tool for evaluating medicine adherence of CKD patients. Methods In the preliminary stage, we formed the prediction scale after three rounds Delphi method and it was filled by 20 patients, who were selected randomly. After pre-investigation and language adaption, we adjusted the prediction measurement scale which included 31 items based on Knowledge-Attitude-Belief Theory. Then, 222 CKD patients in Guangdong Hospital of traditional Chinese Medicine were investigated by this 31-item scale. We screened 31 items by Items analysis theory, including critical ratio, item correlation analysis, internal consistency analysis, principal component analysis and other methods. The left 26 items made up a formal scale. We collected and analyzed data of the 26-item scale and Chinese version of MGL scale, and took their scores correlation analysis as the criterion validity of the 26-item scale. At the same time, we evaluated content validity, Cronbach alpha coefficient and retest reliability of the 26-item scale. Results We developed a scale with 26 items and 5 dimensions finally. In the validation analysis, the scale had good construct validity and content validity. The Pearson relation index between respective scores of the scale and Chinese version of MGL scale was 0.426, P

The laser ablation synthesis in solution (LASiS) method has been widely utilized due to its significant prospects in laser microprocessing of nanomaterials. In this study, the LASiS method with the addition of different surfactant charges (cationic CTAB, nonionic TX-100, and anionic SDS) was used to produce Au NPs. An Nd:YAG laser system at 532 nm excitation with some synthetic parameters, including different laser fluences, ablation times, and surfactant concentrations was performed. The obtained Au NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, and zeta potential analyzer. The Au NPs exhibited the maximum absorption peak at around 520 nm for all samples. The color of Au NPs was changed from red to reddish by increasing the laser fluence. The surfactant charges also played different roles in the Au NPs’ growth during the synthesis process. The average sizes of Au NPs were found to be 8.5 nm, 5.5 nm, and 15.5 nm with the medium containing CTAB, TX-100, and SDS, respectively. Besides, the different surfactant charges induced different performances to protect Au NPs from agglomeration. Overall, the SDS and CTAB surfactants exhibited higher stability of the Au NPs compared to the Au NPs with TX-100 surfactant.

Qiong Huang,1,2 Li Luo,1 Bing-qing Xia,1 Ding-Jun Zhang,1 Chen-di Dong,1 Jiao-wang Tan,1,3 Li-zhe Fu,4 Fang Tang,4 Xian-long Zhang,1 Bei-ni Lao,1 Yan-min Xu,1 Hui-fen Chen,1 Xu-sheng Liu,5 Yi-fan Wu5 1The Second Clinical College, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People’s Republic of China; 2Blood Purification Center, Heyuan Hospital of Traditional Chinese Medicine, Heyuan, Guangdong, People’s Republic of China; 3Renal Division, Beijing University of Traditional Chinese Medicine Shenzhen Hospital, Shenzhen, Guangdong, People’s Republic of China; 4Chronic Disease Management Outpatient Department, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, Guangdong, People’s Republic of China; 5Renal Division, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, Guangdong, People’s Republic of ChinaCorrespondence: Yi-fan WuRenal Division, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), No. 111 Dade Road, Yuexiu District, Guangzhou 510120, People’s Republic of ChinaTel/ Fax +86-20-81887233Email wuyifan007@gzucm.edu.cnPurpose: This study aimed to simplify the version-1 Chinese and Western medication adherence scale for patients with chronic kidney disease (CKD) to a version-2 scale using item response theory (IRT) analyses, and to further evaluate the performance of the version-2 scale.Materials and Methods: Firstly, we refined the version-1 scale using IRT analyses to examine the discrimination parameter (a), difficulty parameter (b) and maximum information function peak (Imax). The final scale refinement from version-1 to version-2 scale was also decided upon clinical considerations. Secondly, we analyzed the reliability and validity of version-2 scale using classical test theory (CTT), as well as difficulty, discrimination and Imax of version-1 and version-2 scale using IRT in order to conduct scale evaluation.Results: For scale refinement, the 26-item version-1 scale was reduced to a 15-item version-2 scale after IRT analyses. For scale evaluation using CTT, internal consistency reliability (total Cronbach α = 0.842) and test-rest reliability (r = 0.909) of version-2 scale were desirable. Content validity indicated 3 components of knowledge, belief and behaviors. We found meritorious construct validity with 3 detected components as the same construct of medication knowledge (items 1– 9), medication behavior (items 13– 15), and medication belief (items 10– 12) based upon exploratory factor analysis. The correlation between the version-2 scale and Morisky, Green and Levine scale (MGL scale) was weak (Pearson coefficient = 0.349). For scale evaluation with IRT, the findings showed enhanced discrimination and decreased difficulty of most retained items (items 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15), decreased Imax of items 1, 2, 3, 4, 6, 11, 14, as well as increased Imax of items 5, 7, 8, 9, 10, 12, 13, 14, 15 in the version-2 scale than in the version-1 scale.Conclusion: The original Chinese and Western medication adherence scale was refined to a 15-item version-2 scale after IRT analyses. The scale evaluation using CTT and IRT showed the version-2 scale had the desirable reliability, validity, discrimination, difficulty, and information providedoverall. Therefore, the version-2 scale is clinically feasible to assess the medication adherence of CKD patients.Keywords: chronic kidney disease, traditional Chinese medicine, medication adherence scale, item response theory

Recently, gold nanoparticles (Au NPs) have been used to study the treatment of malignant tumors due to their higher biocompatibility and lesser toxicity. In addition, they can be excited through a specific wavelength to produce oscillating plasmonic photothermal therapy (PPTT) on the basis of the localized surface plasma resonance (LSPR) effect. Au NPs can be heated to kill cancer cells in specific parts of the body in a noninvasive manner. In this study, branched gold nanoparticles (BAu NPs) were prepared by mixing HAuCl4 in a 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer solution in a molar ratio of 1:2000. The UV&ndash, vis absorption peak was detected in the range of 700&ndash, 1000 nm. Subsequently, BAu NPs were chemically linked to a thiol-modified mannoside molecule via a stable sulfur&ndash, Au covalent bond (Man@BAu NPs). Due to the presence of abundant mannose receptors on human-breast-cancer cells, MDA-MB-231, Man@BAu NPs were found to be abundant inside cancer cells. After irradiating the Man@BAu NP-laden MDA-MB231 switch with a near-infrared (NIR) laser at 808 nm wavelength, the photothermal-conversion effect raised the surface temperature of Man@BAu NPs, thus inducing cell death. Our experiment results demonstrated the advantages of applying Man@BAu NPs in inducing cell death in MDA-MB-231.

A dibenzo[b,j][1,10]phenanthroline (DBPhen) scaffold as a novel colorimetric Cu2+ sensor was proposed and prepared in this study. The optical properties of DBPhen were measured utilizing UV light, UV&ndash, VIS spectroscopy, and fluorescence spectroscopy. The findings denote that DBPhen exhibited a particular selectivity and great sensitivity to Cu2+ compared with other metal ions. The addition of Cu2+ in the DBPhen solution induced the color change from yellow to purple, and a new peak in the visible range (~545 nm) was observed. The detection limit of Cu2+ in the aqueous solution was calculated to be as low as 0.14 &mu, M. Besides, the color change of the DBPhen/Cu2+ complex could be reversibly restored by adding CN&minus, Therefore, DBPhen could have a prospective implementation as a practical colorimetric sensor to detect Cu2+ ions in environmental fields.

This study adopts a simple but facile process for preparing silver-doped magnetic nanoparticles by the spontaneous oxidation-reduction/coprecipitation method. The preparation can be achieved in one pot with a single step, and the prepared silver-doped magnetic nanoparticles were utilized as nanocatalysts for the reduction of o-nitroaniline. Utilizing the magnetic characteristics of the prepared nanoparticles, the catalytic reactions can be carried out under quasi-homogeneous condition and the nanocatalysts can be easily collected after the conversion is achieved. It can be revealed from the results that the morphologies and the composition of the prepared silver-doped magnetic nanoparticles can be adjusted by changing the conditions during the production, which affects the efficacy of the catalysis. In addition, the catalysis efficiency is also controlled by the pH, temperature, and the amounts of nanocatalysts used during the catalytic reaction. Finally, the silver-doped magnetic nanocatalysts prepared in this study own the advantages of easy preparation, room-temperature catalysis, high conversion ability, and recyclability, which make them more applicable in real utilities.

Background Chemoresistance is a major obstacle that limits the benefits of 5-Fluorouracil (5-Fu)-based chemotherapy for colon cancer patients. Autophagy is an important cellular mechanism underlying chemoresistance. Recent research advances have given new insights into the use of natural bioactive compounds to overcome chemoresistance in colon cancer chemotherapy. As one of the multitargeted and safer phytomedicines, curcumin has been reported to work as cancer-specific chemosensitizer, presumably via induction of autophagic signaling pathways. The precise therapeutic effect of curcumin on autophagy in determining tumorous cells’ fate, however, remains unclear. This study was conducted to investigate the differential modulations of the treatments either with 5-Fu alone or 5-Fu combined with curcumin on cellular autophagic responses and viabilities in the human colon cancer cells HCT116 and HT29, and explore molecular signaling transductions underlying the curcumin-mediated autophagic changes and potentiation of 5-Fu’s cytotoxicity in vitro and in vivo. Methods Cell proliferation assay and morphology observation were used to identify the cytotoxicity of different combinations of curcumin and 5-Fu in HCT116 and HT29 cells. Cell immunofluorescence assay, Flow cytometry and Western blot were employed to detect changes of autophagy and the autophagy-related signaling pathways in the colon cancer cells and/or xenograft mice. Results Curcumin could significantly augment the cytotoxicity of 5-Fu to the tumorous cells, and the pre-treatment with curcumin followed by 5-Fu (pre-Cur) proved to be the most effective one compared to other two combinations. The chemosensitizing role of curcumin might attribute to the autophagy turnover from being activated in 5-Fu mono-treatment to being inhibited in the pre-Cur treatment as indicated by the changes in expression of beclin-1, p62 and LC3II/LC3I and the intensity of Cyto-ID Green staining. The autophagic alterations appeared to be contributed by down-regulation of not only the phospho-Akt and phospho-mTOR expressions but the phospho-AMPK and phospho-ULK1 levels as well. The cellular activation of AMPK by addition of A-769662 to the pre-Cur combination resulted in reversed changes in expressions of the autophagy protein markers and apoptotic status compared to those of the pre-Cur combination treatment. The findings were validated in the xenograft mice, in which the tumor growth was significantly suppressed in the mice with 25-day combination treatment, and meanwhile expressions of the autophagy markers, P-AMPK and P-ULK1 were all reversely altered in line with those observed in HCT116 cells. Conclusion Pre-treatment with curcumin followed by 5-Fu may mediate autophagy turnover both in vitro and in vivo via AMPK/ULK1-dependent autophagy inhibition and AKT modulation, which may account for the increased susceptibility of the colon cancer cells/xenograft to the cytotoxicity of 5-Fu.

To facilitate direct spectroscopic observation of hydrogen chloride anions (HCl−), electron bombardment of CH3Cl diluted in excess Ar during matrix deposition was used to generate this anion. Subsequent characterization were performed by IR spectroscopy and quantum chemical calculations. Moreover the band intensity of HCl− decays slowly when the matrix sample is maintained in the dark for a prolonged time. High-level ab inito calculation suggested that HCl− is only weakly bound. Atom-in-molecule charge analysis indicated that both atoms of HCl− are negatively charged and the Cl atom is hypervalent.

Hypervalent molecules are one of the exceptions to the octet rule. Bonding in most hypervalent molecules is well rationalized by the Rundle–Pimentel model (three-center four-electron bond), and high ionic bonding between the ligands and the central atom is essential for stabilizing hypervalent molecules. Here, we produced one of the simplest hypervalent anions, HF−, which is known to deviate from the Rundle–Pimentel model, and identified its ro-vibrational features. High-level ab inito calculations reveal that its bond dissociation energy is comparable to that of dihalides, as supported by secondary photolysis experiments with irradiation at various wavelengths. The charge distribution analysis suggested that the F atom of HF− is negative and hypervalent and the bonding is more covalent than ionic.

The benchmark study of DFT methods on the activation energies of phosphodiester C3'-O and C5'-O bond ruptures and glycosidic C1'-N bond ruptures induced by electron attachment was performed. While conventional pure and hybrid functionals provide a relatively reasonable description for the C1'-N bond rupture, they significantly underestimate the energy barriers of the C-O bond ruptures. This is because the transition states of the later reactions, which are characterized by an electron distribution delocalized from the nucleobase to sugar-phosphate backbone, suffer from a severe self-interaction error in common DFT methods. CAM-B3LYP, M06-2X, and ωB97XD are the top three methods that emerged from the benchmark study; the mean absolute errors relative to the CCSD(T) values are 1.7, 1.9, and 2.2 kcal/mol, respectively. The C-O bond cleavages of 3'- and 5'-dXMP(•-), where X represents four nucleobases, were then recalculated at the M06-2X/6-31++G**//M06-2X/6-31+G* level, and it turned out that the C-O bond cleavages do not proceed as easily as previously predicted by the B3LYP calculations. Our calculations revealed that the C-O bonds of purine nucleotides are more susceptible than pyrimidine nucleotides to the electron attachment. The energies of electron attachment to nucleotides were calculated and discussed as well.

A novel open-framework cadmium selenite bromide, [Cd 10 (SeO 3 ) 8 Br 4 ]·HBr·H 2 O ( 1) , has been obtained by a solid-state reaction at 450 °C, and the structure has been determined by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in Pbcm of the orthorhombic system: a =10.882(3), b =16.275(5), c =18.728(6) A, V =3317(2) A 3 , R 1/ wR 2=0.0411/0.0659. Compound 1 is characteristic of a novel 3-D open-framework structure, composing ∞ 2 [CdSeO 3 ] layers and the pillars of edge-shared CdO 3 Br 2 square pyramids. The lattice water molecules and the HBr molecules locate in the voids of the framework. Optical absorption spectrum of 1 reveals the presence of an optical gap of 1.65 eV. Solid-state photoluminescent study indicates that compound 1 exhibits strong violet emission. TG–DSC measurement shows that compound 1 is thermally stable up to 200 °C.

Two μ₂-tetrazolyl bridged metal complexes, ([CdI(PTZ)(H₂O)]·H₂O)ₙ1 and ([Cu(PTZ)₂]·H₂O)ₙ2 (HPTZ=5-(pyrazinyl) tetrazolate), were hydrothermally synthesized and fully characterized by X-ray crystallography, elemental analyses and spectrum techniques. In 1, cadmium ions are bridged by tridentate μ₂-κ²N2,N5:κ¹N1 chelating PTZ⁻ ligand and halide linkers into an infinite 1D chain, while in 2 copper ions are connected by tridentate μ₂-κ²N7,N12:κ¹N8 and bidentate μ₂-κ¹N1:κ¹N2 chelating-bridging PTZ⁻ ligands to form a 1D castellated chain structure. Compound 1 displays phosphorescence with a lifetime of ~7.74 ms in the visible region, and the origin of the luminescent emission is primary assigned to the combination of ligand-centered emission, metal-to-ligand charge transfer and ligand-to-ligand charge transfer, which has been probed by the density of states (DOS) calculations. Magnetic measurement reveals that compound 2 displays an anti-ferromagnetic ordering. - Graphical abstract: Two new complexes based on 5-(pyrazinyl) tertrazolate, namely ([CdI(PTZ)(H2O)]·H2O)n and ([Cu(PTZ)2]·H2O)n have been synthesized and characterized. Compound 1 exhibits interesting green luminescence. Compound 2 displays an anti-ferromagnetic ordering. Highlights: • We report two novel 1D μ₂-tetrazolyl bridged Cd(II) and Cu(II) compounds. • The cadmium(II) compound exhibits a green luminescence. • Theoretical calculations were conducted to elucidate the green luminescence. • The Cu(II) compound exhibits an anti-ferromagnetic ordering.

The absorption spectrum of ethyne, C2H2, in solid Ar was measured in the wavelength region 107-220 nm with light from a synchrotron. Based on that absorption, irradiation of samples of ethyne dispersed in neon with vacuum-ultraviolet (VUV) radiation yielded various products that were identified through their infrared absorption spectra including C n (n = 3-12), C2H, C2H3, C4H, C4H2, C8H–, and C8H2. The efficiency of photolysis of ethyne and the nature of photoproducts depend on the selected wavelength of VUV light. Information about the photodissociation of C2H2 with various photon energies and the formation and identification of large carbon clusters and hydrides at low temperature might be useful in photochemical models to simulate the composition of the atmosphere of Titan and as a source of aerosols.

Photolysis of methane dispersed (1/1000) in solid Ne at 3 K with vacuum-ultraviolet light from a synchrotron produced infrared absorption lines of several products, including new lines at 3319.3 and 1955.5 cm–1. Based on experiments with isotopic labeling and results of quantum-chemical calculations, these lines are assigned to the C-H stretching and C=C stretching modes, respectively, of interstellar molecule linear C5H radicals.

A mixture of O(3) and CO(2) was irradiated with light from a KrF laser at 248 nm; time-resolved infrared emission of CO(2) in the region 2000-2400 cm(-1) was observed with a Fourier transform spectrometer. This emission involves one quantum in the asymmetric stretching mode (nu(3)) of CO(2) in highly vibrationally excited states. The band contour agrees satisfactorily with a band shape calculated based on a simplified polyad model of CO(2) and a vibrational distribution estimated through a statistical partitioning of energy of approximately 13,000 cm(-1), approximately 3100 cm(-1) smaller than the available energy, into the vibrational modes of CO(2). From this model, approximately 44% and 5% of the available energy of O((1)D) + CO(2) is converted into the vibrational and rotational energy of product CO(2), respectively, consistent with previous reports of approximately 50% for the translational energy. An extent of rotational excitation of CO(2) much smaller than that expected from statistical calculations indicates a mechanism that causes a small torque to be given to CO(2) when an O atom leaves the complex CO(3) on the triplet exit surface of potential energy, consistent with quantum-chemical calculations.

Prototropic equilibria in ionized DNA play an important role in charge transport and radiation damage of DNA and, therefore, continue to attract considerable attention. Although it is well-established that electron attachment will induce an interbase proton transfer from N1 of guanine (G) to N3 of cytosine (C), the question of whether the surrounding water in the major and minor grooves can protonate the one-electron-reduced G:C base pair still remains open. In this work, density functional theory (DFT) calculations were employed to investigate the energetics and mechanism for the protonation of the one-electron-reduced G:C base pair by water. Through the calculations of thermochemical cycles, the protonation free energies were estimated to be in the range of 11.6-14.2 kcal/mol. The calculations for the models of C(•-)(H(2)O)(8) and G(-H1)(-)(H(2)O)(16), which were used to simulate the detailed processes of protonation by water before and after the interbase proton transfer, respectively, revealed that the protonation proceeds through a concerted double proton transfer involving the water molecules in the first and second hydration shells. Comparing the present results with the rates of interbase proton transfer and charge transfer along DNA suggests that protonation on the C(•-) moiety is not competitive with interbase proton transfer, but the possibility of protonation on the G(-H1)(-) moiety after interbase proton transfer cannot be excluded. Electronic-excited-state calculations were also carried out by the time-dependent DFT approach. This information is valuable for experimental identification in the future.

Chemical reactions of C2H4 dispersed in solid nitrogen at 10 K that occur upon irradiation with Lyα light at a wavelength of 121.6 nm and 500 eV electrons were investigated by measuring the infrared absorption spectra. Photolysis of the matrix samples with 121.6 nm light yielded products, including C2H2, CN, and isomers of C2N2, as well as a pair of HCN and HNC. In contrast, electron bombardment of similar matrix samples mainly resulted in the generation of N3, C2H2, C2H3, C3H2, and C3N−. Mechanisms of the reactions that occur during the photolysis and electron-radiation of the matrix samples are discussed. The results of the study provide insights into the formation of HNC and HCN, as well as nitriles, in N2-rich ice samples containing a small proportion of C2H4.

Following collisions of O (1D) with CO, rotationally resolved emission spectra of CO (1 < or = v < or = 6) in the spectral region 1800-2350 cm(-1) were detected with a step-scan Fourier transform spectrometer. O (1D) was produced by photolysis of O3 with light from a KrF excimer laser at 248 nm. Upon irradiation of a flowing mixture of O3 (0.016 Torr) and CO (0.058 Torr), emission of CO (v < or = 6) increases with time, reaches a maximum approximately 10 micros. At the earliest applicable period (2-3 micros), the rotational distribution of CO is not Boltzmann; it may be approximately described with a bimodal distribution corresponding to temperatures approximately 8000 and approximately 500 K, with the proportion of these two components varying with the vibrational level. A short extrapolation from data in the period 2-6 micros leads to a nascent rotational temperature of approximately 10170 +/- 600 K for v = 1 and approximately 1400 +/- 40 K for v = 6, with an average rotational energy of 33 +/- 6 kJ mol(-1). Absorption by CO (v = 0) in the system interfered with population of low J levels of CO (v = 1). The observed vibrational distribution of (v = 2):(v = 3):(v = 4):(v = 5):(v = 6) = 1.00:0.64:0.51:0.32:0.16 corresponds to a vibrational temperature of 6850 +/- 750 K. An average vibrational energy of 40 +/- 4 kJ mol(-1) is derived based on the observed population of CO (2 < or = v < or = 6) and estimates of the population of CO (v = 0, 1, and 7) by extrapolation. The observed rotational distributions of CO (1 < or = v < or = 3) are consistent with results of previous experiments and trajectory calculations; data for CO (4 < or = v < or = 6) are new.

Electron bombardment of gaseous N2 produces N2 + and N3, which are subsequently trapped in the N2 matrix at 10 K. Both the infrared and ultraviolet absorption spectra of the matrix sample at various stages of electron irradiation were recorded. Apart from a progression observed below 192 nm, with intervals ~900 cm–1, corresponding to the transition of D 2 Π g ← X 2 Σ g + of N2 +, three new progressions were recorded in the range 225-192 nm, with intervals ~1000 cm–1, that correlated well with variations in intensities of the electronic absorption band of N3 at 272.7 nm; an absorption coefficient of 3.76 × 10–17 cm molecule–1 for the transition A 2Σu +← X 2Πg of N3 was estimated for the first time. These newly observed progressions were characterized and the vertical excitation energy and oscillator strength were calculated using time-dependent, density-functional theory. This was based on assigning the three progressions to electronic transitions of N3 from the ground state to 2 2Πu, 1 2Σg +, and 1 2Σg –, respectively.

The infrared (IR) and ultraviolet (UV) absorption spectra of pure solid N2 and CH4 diluted in solid N2 (1/100) irradiated with energetic electrons at 10 K were obtained. The IR absorption measurements of the electron-bombarded pure N2 solid reveal the formation of N3 and N3 +, which was confirmed by the observed electronic transitions A 2Σu +← X 2Πg of N3 and A 3Πu ← X 3Σg – of N3 +. In the case of N2 ice containing a small proportion of CH4, we have identified the products of irradiated CH4/N2 ice, including N3, C n N (n = 1-3), CN2, (CN)2, CH3N, HCN2, HC2N, C(NH)2, HNC, HCN, CH3, C2H, C2H2, CN–, NH3 +, and HC3N+. UV absorption measurement of the ice sample was carried out and the possible carriers associated with the observed absorption bands were assigned and discussed.

Absorption spectra and absorption cross sections of gaseous acetylene, C2H2, at 298 and 85?K were measured in the wavelength range 110-155?nm with a slit-jet system coupled to a synchrotron as a source of vacuum ultraviolet light. Using published spectral parameters of C2H2, we simulated the absorption profile for the Rydberg transition to state 4R 0 in the range 124.6-125.1?nm, according to which the temperature of the jet-expanded sample at stagnation pressure 200 Torr is 85?? 5?K. Our cross sections of C2H2 are applicable for determining properties sensitive to temperature for diagnostic work on Saturn and Titan.