Transition-metal complexes of the types Re(CO)3Cl(NN), Re(CO)3py(NN)+, and Cu(PPh3)2(NN)+, where NN = 4,4′-bis(5-phenyl-1,3,4-oxadiazol-2-yl)-2,2′-bipyridine (OX) and ...4,4′-bis(N,N-diphenyl-4-ethen-1-yl-aniline)-2,2′-bipyridine (DPA), have been synthesized and characterized. Crystal structures for Re(CO)3Cl(DPA) and Cu(PPh3)2(OX)BF4 are presented. The crystal structure of the rhenium complex shows a trans arrangement of the ethylene groups, in agreement with density functional theory calculations. The structure of the copper complex displays the planar aromatic nature of the bpy–oxadiazole ligand. Density functional theory modeling of the complexes was supported by comparison of calculated and experimental normalized Raman spectra; the mean absolute deviations of the complexes were <10 cm–1. The Franck–Condon state was investigated using UV–vis and resonance Raman spectroscopic as well as density functional theory computational techniques. It was shown that the lowest energy absorption peaks are metal to ligand charge transfer and ligand-centered charge transfer for the oxadiazole- and diphenylaniline-substituted bipyridine ligands, respectively. The lowest energy excited states were characterized using transient emission and absorption spectroscopic techniques in conjunction with density functional theory calculations. These showed that the DPA complexes had ligand-centered nonemissive “dark” states with lifetimes ranging from 300 to 2000 ns.
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The impact of atmospheric reactive nitrogen (N.sub.r) deposition on carbon (C) sequestration in soils and biomass of unfertilized, natural, semi-natural and forest ecosystems has been much debated. ...Many previous results of this dC/dN response were based on changes in carbon stocks from periodical soil and ecosystem inventories, associated with estimates of N.sub.r deposition obtained from large-scale chemical transport models. This study and a companion paper (Flechard et al., 2020) strive to reduce uncertainties of N effects on C sequestration by linking multi-annual gross and net ecosystem productivity estimates from 40 eddy covariance flux towers across Europe to local measurement-based estimates of dry and wet N.sub.r deposition from a dedicated collocated monitoring network. To identify possible ecological drivers and processes affecting the interplay between C and N.sub.r inputs and losses, these data were also combined with in situ flux measurements of NO, N.sub.2 O and CH.sub.4 fluxes; soil NO3- leaching sampling; and results of soil incubation experiments for N and greenhouse gas (GHG) emissions, as well as surveys of available data from online databases and from the literature, together with forest ecosystem (BASFOR) modelling.
A series of dipyrido3,2-a:2′,3′-cphenazine (dppz)-based ligands with electron-withdrawing substituents and their Re(CO)3(L)Cl and Re(CO)3(L)(py)PF6 complexes have been studied using Raman, resonance ...Raman, and transient resonance Raman (TR2) and time-resolved infrared (TRIR) spectroscopic techinques in conjunction with computational chemistry as well as electrochemical studies, emission, and absorption of ground and excited states. DFT (B3LYP) frequency calculations show good agreement with nonresonant Raman spectra, which allowed these to be used to identify phenanthroline, phenazine, and delocalized modes. These band assignments were used to establish the nature of chromophores active in resonance Raman spectra, probed with wavelengths between 350.7 and 457.9 nm. X-ray crystallography of Re(CO)3(dppzBr2)Cl and Re(CO)3(dppzBr)(py)PF6 showed these crystallize in space groups triclinic P1 and monoclinic P21/n , respectively. Electrochemical studies showed that substituents have a strong effect on the phenazine MO, changing the reduction potential by 200 mV. Transient absorption studies showed that generally the Re(CO)3(L)(py)PF6 complexes had longer lifetimes than the corresponding Re(CO)3(L)Cl complexes; the probed state is likely to be 3π → π* (phz) in nature. TR2 spectra of the ligands provided a marker for the triplet π → π* state, and the TR2 spectra of the complexes suggest an intraligand (IL) π,π* state for Re(CO)3(L)(py)+ complexes, and a potentially mixed IL/MLCT state for Re(CO)3(L)Cl complexes. TRIR spectroscopy is more definitive with THEXI state assignments, and analysis of the metal–carbonyl region (1800–2100 cm–1) on the picosecond and nanosecond time scales indicates the formation of MLCT(phen/phz) states for all Re(CO)3(L)Cl complexes, and IL π → π* (phen) states for all Re(CO)3(L)(py)+ complexes, with all but Re(CO)3(dppzBr(CF3))(py)+ showing some contribution from an MLCT(phen) state also.
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There are numerous transcriptional, proteomic and functional differences between monocyte-derived dendritic cells (Mo-DC) and primary blood dendritic cells (BDC). The CMRF-56 monoclonal antibody ...(mAb) recognizes a cell surface marker, which is upregulated on BDC following overnight culture. Given its unique ability to select a heterogeneous population of BDC, we engineered a human chimeric (h)CMRF-56 IgG4 mAb to isolate primary BDC for potential therapeutic vaccination. The ability to select multiple primary BDC subsets from patients and load them with in vitro transcribed (IVT) mRNA encoding tumor antigen might circumvent the issues limiting the efficacy of Mo-DC. After optimizing and validating the purification of hCMRF-56
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BDC, we showed that transfection of hCMRF-56
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BDC with mRNA resulted in efficient mRNA translation and antigen presentation by myeloid BDC subsets, while preserving superior DC functions compared to Mo-DC. Immune selected and transfected hCMRF-56
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BDC migrated very efficiently in vitro and as effectively as cytokine matured Mo-DC in vivo. Compared to Mo-DC, hCMRF-56
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BDC transfected with influenza matrix protein M1 displayed superior MHC peptide presentation and generated potent antigen specific CD8
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T-cell recall responses, while Wilms tumor 1 (WT1) transfected CMRF-56
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BDC generated effective primary autologous cytotoxic T-cell responses. The ability of the combined DC subsets within hCMRF-56
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BDC to present mRNA delivered tumor antigens merits phase I evaluation as a reproducible generic platform for the next generation of active DC immune therapies.
Application of plant growth regulators to hybrid bermudagrass Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt Davy putting greens is a common management practice used to reduce clipping ...yield and improve aesthetic and functional turfgrass quality. Growing degree day (GDD) models have explored the effects of plant growth regulator application timing on ultradwarf hybrid bermudagrass clipping yield. However, there is a need for research evaluating effects of GDD‐timed plant growth regulator applications on turfgrass quality and ball roll. A field study was conducted in summer 2018 at three locations (Knoxville, TN; Raleigh, NC; and Starkville, MS) to determine the effects of trinexapac‐ethyl (TE) applied according to a GDD model on ultradwarf hybrid bermudagrass putting green quality and ball roll compared to calendar‐based treatment (i.e., weekly or twice‐weekly). For GDD applications, TE was applied at either 20 or 33 g ha−1. GDD based applications were made once 220 GDD (base 10°C) accumulated after each treatment. TE was applied at either 20 or 33 g ha−1 for weekly treatments and rate reduced to either 14 or 16 g ha−1 for the twice‐weekly treatment. In all locations, TE applied on a 220 GDD10C schedule resulted in turfgrass quality greater than or equal to that of the weekly and twice‐weekly applied treatments. Ball roll distance was slightly lower in plots treated with TE every 220 GDD10C compared to the weekly and twice‐weekly treatments, although differences may be negligible to golfers (13 to 23 cm). Ball roll distance was negatively correlated with clipping yield (−0.37 to −0.69). Turfgrass managers choosing to regulate ultradwarf hybrid bermudagrass greens with TE should consider applying on a GDD rather than calendar‐based interval to achieve improved turfgrass quality without sacrificing ball roll distance.
Scardinius racovitzai appeared to be locally adapted to an extreme high temperature environment (26–35 °C). As a species of conservation concern, due to declining ecological condition of the solitary ...thermal lake it could be found in (Lake Petea, Oradea, Romania) and eventual near complete abstraction of this lake, 60 adults were saved in 2014. In this study we investigated methods for induced spawning and sperm cryopreservation to aid recovery and reintroduction to restored habitats. Induced spawning was introduced successfully by intraperitoneal induction of dried carp pituitary extract and human chorion gonadotropin. Larvae and juveniles were successfully reared to age 3 months using standard methods for cyprinids. Our experiments on the cryopreservation of S. racovitzai sperm show that the extender consisting 40 mM KCl 200 mM glucose, 30 mM Tris buffered with HCL pH 8.0 is suitable for freezing warm water rudd sperm together with methanol as a cryoprotectant. By rescuing the remaining wild stock into captivity and undertaking propagation research we have prevented extinction of this rare species – more so S. racovitzai will be important in the study of freshwater fishes and how they can adapt to significant warming.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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