AA-RGTCN: reciprocal global temporal convolution network with adaptive alignment for video-based person re-identification.

Person re-identification(Re-ID) aims to retrieve pedestrians under different cameras. Compared with image-based Re-ID, video-based Re-ID extracts features from video sequences that contain both spatial features and temporal features. Existing methods usually focus on the most attractive image parts, and this will lead to redundant spatial description and insufficient temporal description. Other methods that take temporal clues into consideration usually ignore misalignment between frames and only focus on a fixed length of one given sequence. In this study, we proposed a Reciprocal Global Temporal Convolution Network with Adaptive Alignment(AA-RGTCN). The structure could address the drawback of misalignment between frames and model discriminative temporal representation. Specifically, the Adaptive Alignment block is designed to shift each frame adaptively to its best position for temporal modeling. Then, we proposed the Reciprocal Global Temporal Convolution Network to model robust temporal features across different time intervals along both normal and inverted time order. The experimental results show that our AA-RGTCN can achieve 85.9% mAP and 91.0% Rank-1 on MARS, 90.6% Rank-1 on iLIDS-VID, and 96.6% Rank-1 on PRID-2011, indicating we could gain better performance than other state-of-the-art approaches.

The effects of physical exercise on anxiety symptoms of college students: A meta-analysis.

Objective: This study aimed to evaluate the effect of an exercise intervention on improving and alleviating anxiety symptoms in college students with a meta-analytical approach. Methods: Several databases (e.g., PubMed, Embase, and the Cochrane Library) were used to search for randomized controlled trials (in short, RCTs) on interventions for physical exercise or aerobic exercise in college students with anxiety symptoms. Stata software, version 16.0, was applied sequentially for traditional meta-analysis, subgroup analysis, and publication bias analysis. Results: A total of nine papers were included. The total literature effect [SMD = -0.55, 95% CI = -0.76 to -0.35, Z = 5.38 (P < 0.001)] indicated that physical activity had a significant effect on alleviating anxiety. Subgroup analysis also showed that exercise interventions using aerobic exercise or yoga were effective in relieving anxiety (SMD = -0.39, 95% CI = -0.74 to -0.04; SMD = -0.76, 95% CI = -1.14 to -0.39). Conclusion: Physical activity interventions were shown to have a positive effect on alleviating anxiety in college students. Aerobic exercise was found to be the optimal mode.

Highly Efficient Ternary Near-Infrared Organic Photodetectors for Biometric Monitoring.

Near-infrared (NIR) small-molecule acceptors that absorb at wavelengths of up to 1000 nm are attractive for applications in organic photodetectors (OPDs) and biometrics. In this study, we incorporated IEICO-4F as the third component for PffBT4T-2OD:PC71BM-based OPDs to provide an efficient NIR response while greatly suppressing the leakage current at reverse bias. By varying the blend ratio and thickness (250-600 nm), we obtained an NIR OPD displaying an ultralow dark-current density (JD = 2.62 nA cm-2), ultrahigh detectivity [D* = 7.2 × 1012 Jones (850 nm)], high sensitivity, and photoresponsivity covering the region from the ultraviolet to the NIR. We used tapping-mode atomic force microscopy, optical microscopy, grazing-incidence wide-angle X-ray scattering, and contact angle measurements to investigate the effect of IEICO-4F on the performance of the ternary OPDs. The low compatibility of PffBT4T-2OD and IEICO-4F, originating from weak intermolecular interactions, allowed us to manipulate the degree of phase separation between the donor and acceptor in the ternary blends, leading to an optimized blend morphology featuring efficient charge separation, transport, and collection. To demonstrate its applicability, we integrated our OPD with two light-emitting diodes and used the system for precisely calculated transmissive pulse oximetry.

Stimulation phosphatidylinositol 3-kinase/protein kinase B signaling by Porphyromonas gingivalis lipopolysacch aride mediates interleukin-6 and interleukin-8 mRNA/protein expression in pulpal inflammation.

BACKGROUND/PURPOSE: The signaling mechanisms for Porphyromonas gingivalis lipopolysaccharide (PgLPS)-induced inflammation in human dental pulp cells are not fully clarified. This in vitro study aimed to evaluate the involvement of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in PgLPS-induced pulpal inflammation. METHODS: Human dental pulp cells (HDPCs) were challenged with PgLPS with or without pretreatment and coincubation with a PI3K/Akt inhibitor (LY294002). The gene or protein levels of PI3K, Akt, interleukin (IL)-6, IL-8, alkaline phosphatase (ALP), osteocalcin and osteonectin were analyzed by reverse transcription polymerase chain reaction (PCR), real-time PCR, western blotting, and immunofluorescent staining. In addition, an enzyme-linked immunosorbent assay was used to analyze IL-6 and IL-8 levels in culture medium. RESULTS: In response to 5 µg/ml PgLPS, IL-6, IL-8, and PI3K, but not Akt mRNA expression of HDPCs, was upregulated. IL-6, IL-8, PI3K, and p-Akt protein levels were stimulated by 10-50 µg/ml of PgLPS in HDPCs. PgLPS also induced IL-6 and IL-8 secretion at concentrations higher than 5 µg/ml. Pretreatment and co-incubation by LY294002 attenuated PgLPS-induced IL-6 and IL-8 mRNA expression in HDPCs. The mRNA expression of ALP, but not osteocalcin and osteonectin, was inhibited by higher concentrations of PgLPS in HDPCs. CONCLUSION: P. gingivalis contributes to pulpal inflammation in HDPCs by dysregulating PI3K/Akt signaling pathway to stimulate IL-6 and IL-8 mRNA/protein expression and secretion. These results are useful for understanding the pulpal inflammation and possible biomarkers of inflamed pulp diagnosis and treatment.

The B-type response regulator GmRR11d mediates systemic inhibition of symbiotic nodulation.

Key to the success of legumes is the ability to form and maintain optimal symbiotic nodules that enable them to balance the trade-off between symbiosis and plant growth. Cytokinin is essential for homeostatic regulation of nodulation, but the mechanism remains incompletely understood. Here, we show that a B-type response regulator GmRR11d mediates systemic inhibition of nodulation. GmRR11d is induced by rhizobia and low level cytokinin, and GmRR11d can suppress the transcriptional activity of GmNSP1 on GmNIN1a to inhibit soybean nodulation. GmRR11d positively regulates cytokinin response and its binding on the GmNIN1a promoter is enhanced by cytokinin. Intriguingly, rhizobial induction of GmRR11d and its function are dependent upon GmNARK that is a CLV1-like receptor kinase and inhibits nodule number in shoots. Thus, GmRR11d governs a transcriptional program associated with nodulation attenuation and cytokinin response activation essential for systemic regulation of nodulation.

A High-Accuracy Detection System: Based on Transfer Learning for Apical Lesions on Periapical Radiograph.

Apical Lesions, one of the most common oral diseases, can be effectively detected in daily dental examinations by a periapical radiograph (PA). In the current popular endodontic treatment, most dentists spend a lot of time manually marking the lesion area. In order to reduce the burden on dentists, this paper proposes a convolutional neural network (CNN)-based regional analysis model for spical lesions for periapical radiographs. In this study, the database was provided by dentists with more than three years of practical experience, meeting the criteria for clinical practical application. The contributions of this work are (1) an advanced adaptive threshold preprocessing technique for image segmentation, which can achieve an accuracy rate of more than 96%; (2) a better and more intuitive apical lesions symptom enhancement technique; and (3) a model for apical lesions detection with an accuracy as high as 96.21%. Compared with existing state-of-the-art technology, the proposed model has improved the accuracy by more than 5%. The proposed model has successfully improved the automatic diagnosis of apical lesions. With the help of automation, dentists can focus more on technical and medical diagnoses, such as treatment, tooth cleaning, or medical communication. This proposal has been certified by the Institutional Review Board (IRB) with the certification number 202002030B0.

Factors associated with positive aspects of caregiving experiences among family caregivers of persons living with dementia in Taiwan: A cross-sectional study.

This study examined the associated factors of positive aspects of caregiving experience among family caregivers of persons living with dementia in Taiwan. This cross-sectional correlational study recruited dyads of primary family caregivers of persons living with dementia by convenience sampling from dementia care centers in northern Taiwan from September 9, 2020, to June 20, 2021. A total of 100 dyads who met inclusions criteria agreed to participate in the study. Significant predictors of positive aspects of caregiving experience were scores of dementia behavior disturbance (t=-3.63, p =<.001), a spousal caregiver (t=2.83, p =.006), and the subscale score for satisfaction on the functional social support (t=2.62, p =.01). Our findings suggest prevention and treatment of dementia behavior disturbance for persons living with dementia, improving satisfaction with functional social support, and focusing on non-spousal caregivers could enhance experiences of positive caregiving for family caregivers.

A Low Memory Requirement MobileNets Accelerator Based on FPGA for Auxiliary Medical Tasks.

Convolutional neural networks (CNNs) have been widely applied in the fields of medical tasks because they can achieve high accuracy in many fields using a large number of parameters and operations. However, many applications designed for auxiliary checks or help need to be deployed into portable devices, where the huge number of operations and parameters of a standard CNN can become an obstruction. MobileNet adopts a depthwise separable convolution to replace the standard convolution, which can greatly reduce the number of operations and parameters while maintaining a relatively high accuracy. Such highly structured models are very suitable for FPGA implementation in order to further reduce resource requirements and improve efficiency. Many other implementations focus on performance more than on resource requirements because MobileNets has already reduced both parameters and operations and obtained significant results. However, because many small devices only have limited resources they cannot run MobileNet-like efficient networks in a normal way, and there are still many auxiliary medical applications that require a high-performance network running in real-time to meet the requirements. Hence, we need to figure out a specific accelerator structure to further reduce the memory and other resource requirements while running MobileNet-like efficient networks. In this paper, a MobileNet accelerator is proposed to minimize the on-chip memory capacity and the amount of data that is transferred between on-chip and off-chip memory. We propose two configurable computing modules: Pointwise Convolution Accelerator and Depthwise Convolution Accelerator, to parallelize the network and reduce the memory requirement with a specific dataflow model. At the same time, a new cache usage method is also proposed to further reduce the use of the on-chip memory. We implemented the accelerator on Xilinx XC7Z020, deployed MobileNetV2 on it, and achieved 70.94 FPS with 524.25 KB on-chip memory usage under 150 MHz.

The Application of an Omentum Graft or Flap in Spinal Cord Injury.

BACKGROUND: Spinal cord injury (SCI) causes a primary injury at the lesion site and triggers a secondary injury and prolonged inflammation. There has been no definitive treatment till now. Promoting angiogenesis is one of the most important strategies for functional recovery after SCI. The omentum, abundant in blood and lymph vessels, possesses the potent ability of tissue regeneration. METHODS: The present work examines the efficacy of autologous omentum, either as a flap (with vascular connection intact) or graft (severed vascular connection), on spinal nerve regeneration. After contusive SCI in rats, a thin sheath of omentum was grafted to the injured spinal cord. RESULTS: Omental graft improved behavior scores significantly from the 3rd to 6th week after injury (6th week, 5.5 ± 0.5 vs. 8.6 ± 1.3, p < 0.05). Furthermore, the reduction in cavity and the preservation of class III ß-tubulin-positive nerve fibers in the injury area was noted. Next, the free omental flap was transposed to a completely transected SCI in rats through a pre-implanted tunnel. The flap remained vascularized and survived well several weeks after the operation. At 16 weeks post-treatment, SCI rats with omentum flap treatment displayed the preservation of significantly more nerve fibers (p < 0.05) and a reduced injured cavity, though locomotor scores were similar. CONCLUSIONS: Taken together, the findings of this study indicate that treatment with an omental graft or transposition of an omental flap on an injured spinal cord has a positive effect on nerve protection and tissue preservation in SCI rats. The current data highlight the importance of omentum in clinical applications.

Toxic mechanisms of Roth801, Canals, microparticles and nanoparticles of ZnO on MG-63 osteoblasts.

ZnO eugenol-based materials are widely used for restoration of caries cavity, apical retrograde filling and root canal sealer. Their effects on apical bone healing await investigation. The toxic mechanisms of ZnO particles and nanoparticles to MG-63 osteoblastic cells were studied. We found the different morphology and size of various particles as observed by scanning electron microscope. Particles of Canals and Roth801 were larger than ZnO-205532 microparticles and ZnO-677450 nanoparticles. Four ZnO particles showed cytotoxicity (>25 µg/ml) as analyzed by MTT. Transmission electron microscope found intracellular vacuoles with particle content. Exposure to ZnO particles induced ROS production and cell cycle arrest as studied by DCF and propidium iodide flow cytometry. ZnO particles activated ATM, ATR, Chk1, Chk2, γ-H2AX, ERK and p38 phosphorylation as detected by immunofluorescent staining and western blotting. The protein expression of cdc2, cyclin B1 and cdc25C were decreased, whereas GADD45α and hemeoxygenase-1 (HO-1) were stimulated. ZnO particles' cytotoxicity to MG63 cells was prevented by N-acetylcysteine (NAC), but not CGK733, AZD7762, U0126 and SB203580. ZnO showed little effect on IL-8 and sICAM-1 secretion. These results indicated that ZnO particles are toxic to osteoblasts. ZnO particles' toxicity were related to ROS, and DNA damage responses, checkpoint kinases, cell cycle arrest, ERK and p38 signaling, but not IL-8 and ICAM-1. These results were useful for materials' development and promote apical healing. Dentists should avoid of extruding ZnO-based sealers excessively over root apex and prevent residual ZnO-based retrograde filling materials in apical area during endodontic practice.

Sulfur-doped g-C3N4 nanosheets for photocatalysis: Z-scheme water splitting and decreased biofouling.

In this study, an S-doped g-C3N4 nanosheet was prepared as a photocatalyst for effective oxygen evolution reaction. Sulfur plays a crucial role in S-doped g-C3N4 not only in increasing the charge density but also in reducing the energy band gap of S-doped g-C3N4 via substitution of nitrogen sites. S-doped g-C3N4 can serve as an oxygen-evolved photocatalyst, when combined with Ru/SrTiO3:Rh in the presence of [Co(bpy)3]3+/2+ as an electron mediator, enables photocatalytic overall water splitting under visible light irradiation with hydrogen and oxygen production rates of 24.6 and 14.5 µmol-h-1, respectively. Moreover, the photocatalytic overall water splitting to produce H2 and O2 using this Z-scheme system could use for five runs to at least 94.5 h under visible light irradiation. On the other hand, S-doped g-C3N4 can reduce biofouling by bacteria such as Escherichia coli by more than 70%, by simply incubating the S-doped g-C3N4 sample with bacterial solution under light irradiation. Our results suggest that S-doped g-C3N4 is a potentially effective, green, and promising material for a variety of photocatalytic applications.

Photocatalytic Dye and Cr(VI) Degradation Using a Metal-Free Polymeric g-C3N4 Synthesized from Solvent-Treated Urea.

The development of visible-light-driven polymeric g-C3N4 is in response to an emerging demand for the photocatalytic dye degradation and reduction of hexavalent chromium ions. We report the synthesis of g-C3N4 from urea treated with various solvents such as methanol, ethanol, and ethylene glycol. The samples were characterized and the Williamson⁻Hall method was applied to investigate the lattice strain of the samples. The activity of the samples was evaluated by observing the degradation of methyl orange and K2Cr2O7 solution under light irradiation. Photocatalytic reaction kinetics were determined as pseudo-first-order and zero-order for the degradation of methyl orange and reduction of hexavalent chromium, respectively. Due to the inhibited charge separation resulting from the small lattice strain, reduced crystal imperfection, and sheet-like structure, g-C3N4 obtained from ethanol-treated urea exhibited the highest activity among the evaluated samples.

Recent Developments in Graphitic Carbon Nitride Based Hydrogels as Photocatalysts.

Solar-driven photocatalysis with graphitic carbon nitride (g-C3 N4 ) is considered to be the most promising approach for the generation of H2 from water, the degradation of organic pollutants, and the reduction of CO2 . However, bulk g-C3 N4 exhibits several drawbacks, such as a low specific surface area, high defect density, and fast charge recombination, which result in low photocatalytic performance. The construction of 3D porous hydrogels for g-C3 N4 through nanostructural engineering is a rapid, feasible, and cost-effective technique to improve the adsorption capability, stability, and separability of the hydrogel composite; to increase the number of active sites; and to create an internal conductive path for facile charge transfer and high photocatalytic activity. This minireview summarizes recent progress in photocatalytic water splitting and dye degradation by using g-C3 N4 -based hydrogels, with respect to state-of-the-art methods for synthesis, preparation, modification, and multicomponent coupling. Furthermore, comprehensive outlooks, future challenges, and concluding remarks regarding the use of g-C3 N4 -based hydrogels as highly efficient photocatalysts are presented.

Attenuating Spinal Cord Injury by Conditioned Medium from Bone Marrow Mesenchymal Stem Cells.

Spinal cord injury (SCI) is a devastating neurological condition and might even result in death. However, current treatments are not sufficient to repair such damage. Bone marrow mesenchymal stem cells (BM-MSC) are ideal transplantable cells which have been shown to modulate the injury cascade of SCI mostly through paracrine effects. The present study investigates whether systemic administration of conditioned medium from MSCs (MSCcm) has the potential to be efficacious as an alternative to cell-based therapy for SCI. In neuron-glial cultures, MSC coculture effectively promoted neuronal connection and reduced oxygen glucose deprivation-induced cell damage. The protection was elicited even if neuron-glial culture was used to expose MSCcm, suggesting the effects possibly from released fractions of MSC. In vivo, intravenous administration of MSCcm to SCI rats significantly improved behavioral recovery from spinal cord injury, and there were increased densities of axons in the lesion site of MSCcm-treated rats compared to SCI rats. At early days postinjury, MSCcm treatment upregulated the protein levels of Olig 2 and HSP70 and also increased autophage-related proteins in the injured spinal cords. Together, these findings suggest that MSCcm treatment promotes spinal cord repair and functional recovery, possibly via activation of autophagy and enhancement of survival-related proteins.

Synthesis, structural characterization and transformation of an eight-electron superatomic alloy, [Au@Ag19{S2P(OPr)2}12].

Controlling the metal nanoclusters with atomic precision is highly difficult and further studies on their transformation reactions are even more challenging. Herein we report the controlled formation of a silver alloy nanocluster [AuAg19{S2P(OnPr)2}12] (1) from an Ag20 template via a galvanic exchange route. X-ray structural analysis reveals that the alloy structure comprises of a gold-centered Ag12 icosahedron, Au@Ag12, capped by seven silver atoms. Interestingly upon reacting with one equiv. of silver(i) salt, (1) can transform into a higher nuclearity nanocluster, [Au@Ag20{S2P(OnPr)2}12]+ (2). The conversion process is studied via ESI mass spectrometry and 31P NMR spectroscopy. This kind of size-structural transformation at the single atom level is quite remarkable. Furthermore, the compositions of all the doped nanoclusters (1, 2) were fully characterized with ESI-MS and EDS. The blue shift depicted in the UV-visible and emission spectra of the doped nanoclusters (1, 2) compared with the precursor, Ag20, demonstrates that the doping atoms have significant effects on the electronic structures.

Low-temperature, simple and efficient preparation of perovskite solar cells using Lewis bases urea and thiourea as additives: stimulating large grain growth and providing a PCE up to 18.8.

We demonstrated that two Lewis bases - urea and thiourea - acted as efficient additives for CH3NH3(MA)PbI3-x Cl x and MAPbI3 perovskite solar cells (PSCs) and observed a significant increase in PCE for the MAPbI3 devices in the presence of 1% urea with a remarkable PCE of 18.8% using an extremely low annealing temperature (85 °C).

Improving the regenerative potential of olfactory ensheathing cells by overexpressing prostacyclin synthetase and its application in spinal cord repair.

BACKGROUND: Olfactory ensheathing cells (OEC), specialized glia that ensheathe bundles of olfactory nerves, have been reported as a favorable substrate for axonal regeneration. Grafting OEC to injured spinal cord appears to facilitate axonal regeneration although the functional recovery is limited. In an attempt to improve the growth-promoting properties of OEC, we transduced prostacyclin synthase (PGIS) to OEC via adenoviral (Ad) gene transfer and examined the effect of OEC with enhanced prostacyclin synthesis in co-culture and in vivo. Prostacyclin is a vasodilator, platelet anti-aggregatory and cytoprotective agent. RESULTS: Cultured OEC expressed high level of cyclooxygneases, but not PGIS. Infection of AdPGIS to OEC could selectively augument prostacyclin synthesis. When cocultured with either OEC or AdPGIS-OEC, neuronal cells were resistant to OGD-induced damage. The resulted OEC were further transplanted to the transected cavity of thoracic spinal cord injured (SCI) rats. By 6 weeks post-surgery, significant functional recovery in hind limbs occurred in OEC or AdPGIS-OEC transplanted SCI rats compared with nontreated SCI rats. At 10-12 weeks postgraft, AdPGIS-OEC transplanted SCI rats showed significantly better motor restoration than OEC transplanted SCI rats. Futhermore, regenerating fiber tracts in the distal spinal cord stump were found in 40-60% of AdPGIS-OEC transplanted SCI rats. CONCLUSIONS: Enhanced synthesis of prostacyclin in grafted OEC improved fiber tract regeneration and functional restoration in spinal cord injured rats. These results suggest an important potential of prostacyclin in stimulating OEC therapeutic properties that are relevant for neural transplant therapies.

[Ag20 {S2 P(OR)2 }12 ]: A Superatom Complex with a Chiral Metallic Core and High Potential for Isomerism.

The synthesis and structural determination of a silver nanocluster [Ag20 {S2 P(OiPr)2 }12 ] (2), which contains an intrinsic chiral metallic core, is produced by reduction of one silver ion from the eight-electron superatom complex [Ag21 {S2 P(OiPr)2 }12 ](PF6 ) (1) by borohydrides. Single-crystal X-ray analysis displays an Ag20 core of pseudo C3 symmetry comprising a silver-centered Ag13 icosahedron capped by seven silver atoms. Its n-propyl derivative, [Ag20 {S2 P(OnPr)2 }12 ] (3), can also be prepared by the treatment of silver(I) salts and dithiophosphates in a stoichiometric ratio in the presence of excess amount of [BH4 ](-) . Crystal structure analyses reveal that the capping silver-atom positions relative to their icosahedral core are distinctly different in 2 and 3 and generate isomeric, chiral Ag20 cores. Both Ag20 clusters display an emission maximum in the near IR region. DFT calculations are consistent with a description within the superatom model of an 8-electron [Ag13 ](5+) core protected by a [Ag7 {S2 P(OR)2 }12 ](5-) external shell. Two additional structural variations are predicted by DFT, showing the potential for isomerism in such [Ag20 {S2 P(OR)2 }12 ] species.

Ferrocene-Functionalized Cu(I)/Ag(I) Dithiocarbamate Clusters.

A series of compounds, namely, [Cu8(µ4-H){S2CNMeCH2Fc}6](PF6) (1), [Cu7(µ4-H) {S2CN(i)PrCH2Fc}6] (2), [Cu3{S2CN(Bz) (CH2Fc)}2(dppf)2](PF6) (3), and [Ag2{S2CNMe(CH2Fc)}2(PPh3)2] (4) (dppf = 1,1'-bis(diphenylphosphino)ferrocene), supported by multiferrocene assemblies, were synthesized. All the compounds were characterized by (1)H NMR, Fourier transform infrared, elemental analysis, and electrospray ionization mass spectrometry techniques. Single-crystal X-ray structural analysis revealed that 1 is a monocationic octanuclear Cu(I) cluster and that 2 is a neutral heptanuclear Cu(I) cluster with tetracapped tetrahedral (1) and tricapped tetrahedral (2) geometries entrapped with an interstitial hydride, anchored by six ferrocene units at the periphery of the core. Compounds 3 and 4 comprise trimetallic Cu(I) and dimetallic Ag(I) cores enfolded by four and two ferrocene moieties. Interestingly both chelating and bridging modes of binding are observed for dppf ligand in 3. Further the formation and isolation of polyhydrido copper clusters [Cu28H15{S2CN(i)PrCH2Fc}12](PF6) (5) and [Cu28H15{S2CN(n)Bu2}12](PF6) (7), stabilized by bulky ferrocenyl and n-butyl dithiocarbamate ligands, was demonstrated. They are readily identified by (2)H NMR studies on their deuterium analogues, [Cu28D15{S2CN(i)PrCH2Fc}12](PF6) (6) and [Cu28D15{S2CN(n)Bu2}12](PF6) (8). Though the structure details as well as spectroscopic characterizations of 5 are yet to be investigated, the compound 7 is fully characterized by variety of spectroscopy including single-crystal X-ray diffraction. The cyclic voltammetry studies for compounds 1, 2, and 4 display irreversible redox peaks for Fe(2+)/Fe(3+) couple wherein the reduction peaks are not well-resolved due to some adsorption of the complex onto the electrode surface.

Au-Au chemical bonding induced by UV irradiation of dinuclear gold(I) complexes: a computational study with experimental evidence.

Two luminescent dinuclear gold(I) species, namely diselenophosphinate [Au2{µ-Se2P((CH2)2Ph)2}2] and dithiophosphinate [Au2{µ-S2P((CH2)2Ph)2}2], exhibiting interesting structural, absorption and emission properties have been studied. In the solid state, both complexes exist in a dinuclear monomeric form, exhibiting no aurophilic interaction, and display similar photophysical properties. It is shown, using DFT computations, that Au-Au chemical bonding appears in the first excited state of these complexes, whereas such bonding does not exist in their ground state; Raman spectroscopy experiments, which bring to light the stretching of this new bond, confirm the theoretical results. Moreover, TDDFT computations permitted us to assign the observed absorption bands of the UV-visible spectra of the two species to LMCT transitions and to describe the emission.