Critical role of hydrogen for superconductivity in nickelates.

The newly discovered nickelate superconductors so far only exist in epitaxial thin films synthesized by a topotactic reaction with metal hydrides1. This method changes the nickelates from the perovskite to an infinite-layer structure by deintercalation of apical oxygens1-3. Such a chemical reaction may introduce hydrogen (H), influencing the physical properties of the end materials4-9. Unfortunately, H is insensitive to most characterization techniques and is difficult to detect because of its light weight. Here, in optimally Sr doped Nd0.8Sr0.2NiO2H epitaxial films, secondary-ion mass spectroscopy shows abundant H existing in the form of Nd0.8Sr0.2NiO2Hx (x ≅ 0.2-0.5). Zero resistivity is found within a very narrow H-doping window of 0.22 ≤ x ≤ 0.28, showing unequivocally the critical role of H in superconductivity. Resonant inelastic X-ray scattering demonstrates the existence of itinerant interstitial s (IIS) orbitals originating from apical oxygen deintercalation. Density functional theory calculations show that electronegative H- occupies the apical oxygen sites annihilating IIS orbitals, reducing the IIS-Ni 3d orbital hybridization. This leads the electronic structure of H-doped Nd0.8Sr0.2NiO2Hx to be more two-dimensional-like, which might be relevant for the observed superconductivity. We highlight that H is an important ingredient for superconductivity in epitaxial infinite-layer nickelates.

CCL19-CCR7-dependent reverse transendothelial migration of myeloid cells clears Chlamydia muridarum from the arterial intima.

Regions of the normal arterial intima predisposed to atherosclerosis are sites of ongoing monocyte trafficking and also contain resident myeloid cells with features of dendritic cells. However, the pathophysiological roles of these cells are poorly understood. Here we found that intimal myeloid cells underwent reverse transendothelial migration (RTM) into the arterial circulation after systemic stimulation of pattern-recognition receptors (PRRs). This process was dependent on expression of the chemokine receptor CCR7 and its ligand CCL19 by intimal myeloid cells. In mice infected with the intracellular pathogen Chlamydia muridarum, blood monocytes disseminated infection to the intima. Subsequent CCL19-CCR7-dependent RTM was critical for the clearance of intimal C. muridarum. This process was inhibited by hypercholesterolemia. Thus, RTM protects the normal arterial intima, and compromised RTM during atherogenesis might contribute to the intracellular retention of pathogens in atherosclerotic lesions.

Unique Viscoelasticity and Hierarchical Relaxation Dynamics of Molecular Granular Materials.

Resulting from the dense packing of subnanometer molecular clusters, molecular granular materials (MGMs) are shown to maintain high elasticity far above their apparent glass transition temperature (Tg*). However, our microscopic understanding of their structure-property relationship is still poor. Herein, 1 nm polyhedral oligomeric silsesquioxanes (POSSs) are appended to a backbone chain in a brush configuration with different flexible linker chains. Assemblies of these brush polymers exhibit hierarchical relaxation dynamics with the glass transition arising from the cooperative dynamics of packed POSSs. The interaction among the assemblies can be strengthened by increasing the rigidity of linkers with the MGM relaxation modes changing from colloid- to polymer chain-like behavior, rendering their tunable viscoelasticity. This finally contributes to the decoupling of mechanical and thermal properties by showing elasticity dominant mechanical properties at a temperature 150 K above the Tg*.

Intermediate bands and p-orbital tuning of the band structure of BiFeO3 for photovoltaic application.

BiFeO3 is a lead-free inorganic ferroelectric material that holds promise for photovoltaic applications. However, its larger band gap poses a challenge for efficient sunlight absorption, limiting its efficiency in such applications. In this work, nitrogen, which has lower electronegativity compared to oxygen, was selected to tune the band gap of BiFeO3. It was discovered that the band gap of BiFeO3-xNx (x = 0.125, 0.25, 0.375, and 0.5) was reduced from the original value of 3.1 eV for the parent phase to 1.45-1.77 eV, which originated from the intermediate bands caused by the stronger interaction between Fe 3d and N 2p and the valence band maximum shifted towards higher energy levels caused by the introduction of N 2p. In particular, the band gaps of 1.45 and 1.49 eV for BiFeO2.75N0.25 and BiFeO2.625N0.375, respectively, were closer to the optimal band gap of approximately 1.4 eV for photovoltaic materials. Accompanied with the reduction in the band gap, the optical absorption coefficient of N-substituted BiFeO3 in the visible range was evidently increased. Noticeably, N-substituted BiFeO3 showed good ferroelectricity with a decreased band gap and increased optical absorption. The presented results thus demonstrate that N substitution is a promising way to improve the ferroelectric photovoltaic properties of BiFeO3.

Design, synthesis, and evaluation of n-butylphthalide and ligustrazine hybrids as potent neuroprotective agents for the treatment of ischemic stroke in vitro and in vivo.

A series of novel NBP-TMP hybrids with neuroprotective effects were designed and synthesized for the treatment of ischemic stroke. The anti-cerebral ischemic activity of these compounds was screened by evaluating their neuroprotective effects on the oxygen glucose deprivation/reperfusion (OGD/R)-induced SH-SY5Y cell injury model in vitro. Nine compounds 7e, 7h-7i, 7k, 7m-7p and 7r showed better activities on cell viability and LDH levels compared to NBP at the concentration of 6.25 µM. Among them, compound 7m showed the best potency with a percentage of protection 90.2 % compared to NBP (69.2 %) and other compounds. Preliminary structure-activity analysis revealed that the introduction of iodine and N-methylpiperazine groups could significantly improve the neuroprotective effect. Further mechanism research showed that compound 7m could reduce the damage to neuronal mitochondria caused by OGD/R by reducing ROS and increasing mitochondrial membrane potential (MMP), and reduce the apoptosis and necrosis of neurons to play a neuroprotective role. In addition, 7m could regulate the levels of mitochondrial apoptosis pathway-related proteins Bcl-2, Bax, and caspase 3. Finally, in vivo experiments showed that the compound 7m significantly inhibited ischemia-reperfusion injury and cerebral blood flow in rats, and showed a more significant neuroprotective effect than the positive drug NBP at a dose concentration of 20 mg/kg. In conclusion, our results suggest that 7m may be used as a novel lead compound for the future development of anti-cerebral ischemic agents.

Supramolecular Assembly and Microscopic Dynamics Modulation of Nanoscale Inorganic Cryptand and Polymer Complex for Versatile Design of Flexible Single-Ion Conductors.

The popular design of solid-state electrolytes (SSEs) from the chain relaxation of polymers faces the trade-offs among ion conductivity, stability, and processability. Herein, 2 nm inorganic cryptand molecules with the capability to carry different types of cations, including Ag+, Na+, K+, and Ca2+, are complexed with cationic polymers via ionic interaction, respectively, and the hybrid materials further phase separate into lamellar or hexagonal columnar structures. The successful establishment of ordered structures with ion channels from the packing of inorganic cryptands confers SSEs' excellent ionic conductivity to versatile types of cations. Meanwhile, suggested from the combination of broad dielectric spectroscopy, rheology, and thermal analysis, the fast chain relaxation can activate the dynamics of inorganic cryptand molecules and facilitate the ion hopping process in ion channels. The supramolecular interaction in the complex enables the highly flexible physical appearance for defect-free contact with electrodes as well as cost-effective processability and recyclability.

Sigma 1 receptor activation improves retinal structure and function in the RhoP23H/+ mouse model of autosomal dominant retinitis pigmentosa.

Retinitis pigmentosa (RP) is a group of devastating inherited retinal diseases that leads to visual impairment and oftentimes complete blindness. Currently no cure exists for RP thus research into prolonging vision is imperative. Sigma 1 receptor (Sig1R) is a promising small molecule target that has neuroprotective benefits in retinas of rapidly-degenerating mouse models. It is not clear whether Sig1R activation can provide similar neuroprotective benefits in more slowly-progressing RP models. Here, we examined Sig1R-mediated effects in the slowly-progressing RhoP23H/+ mouse, a model of autosomal dominant RP. We characterized the retinal degeneration of the RhoP23H/+ mouse over a 10 month period using three in vivo methods: Optomotor Response (OMR), Electroretinogram (ERG), and Spectral Domain-Optical Coherence Tomography (SD-OCT). A slow retinal degeneration was observed in both male and female RhoP23H/+ mice when compared to wild type. The OMR, which reflects visual acuity, showed a gradual decline through 10 months. Interestingly, female mice had more reduction in visual acuity than males. ERG assessment showed a gradual decline in scotopic and photopic responses in RhoP23H/+ mice. To investigate the neuroprotective benefits of Sig1R activation in the RhoP23H/+ mouse model, mutant mice were treated with a high-specificity Sig1R ligand (+)-pentazocine ((+)-PTZ) 3x/week at 0.5 mg/kg and examined using OMR, ERG, SD-OCT. A significant retention of visual function was observed in males and females at 10 months of age, with treated females retaining ∼50% greater visual acuity than non-treated mutant females. ERG revealed significant retention of scotopic and photopic b-wave amplitudes at 6 months in male and female RhoP23H/+ mice treated with (+)-PTZ. Further, in vivo analysis by SD-OCT revealed a significant retention of outer nuclear layer (ONL) thickness in male and female treated RhoP23H/+ mice. Histological studies showed significant retention of IS/OS length (∼50%), ONL thickness, and number of rows of photoreceptor cell nuclei at 6 months in (+)-PTZ-treated mutant mice. Interestingly, electron microscopy revealed preservation of OS discs in (+)-PTZ treated mutant mice compared to non-treated. Taken collectively, the in vivo and in vitro data provide the first evidence that targeting Sig1R can rescue visual function and structure in the RhoP23H/+ mouse. These results are promising and provide a framework for future studies to investigate Sig1R as a potential therapeutic target in retinal degenerative disease.

Zwitterionic Targeting Doxorubicin -Loaded Micelles Assembled by Amphiphilic Dendrimers with Enhanced Antitumor Performance.

Chemotherapy is the main method of treating malignant tumors in clinical treatment. However, the commonly used chemotherapeutic drugs have the disadvantages of high biological toxicity, poor water solubility, low targeting ability, and high side effects. Zwitterionic micelles assembled by amphiphilic dendrimers modified with zwitterionic groups and targeting ligand should largely overcome these shortcomings. Herein, the zwitterionic group and targeting peptide c(RGDfC) were modified on the surface of generation 2 poly(propylene imine) dendrimers (G2 PPI), which was conjugated with hydrophobic N-(2-mercaptoethyl) oleamide to form amphiphilic dendrimers (PPIMYRC). PPIMYRC self-assembled into micelles with doxorubicin (DOX) loaded in the interior of micelles to prepare DOX-loaded micelles (PPIMYRC-DOX micelles). The PPIMYRC-DOX micelles had great stability in fibrinogen and pH-responsive drug release. Furthermore, PPIMYRC-DOX micelles had higher cellular uptake rates than free DOX, resulting in higher cytotoxicity of PPIMYRC-DOX micelles than that of free DOX. More importantly, PPIMYRC-DOX micelles inhibited tumors much better than free DOX. The tumor inhibition rate of PPIMYRC-DOX micelles was as high as 93%. Taken together, PPIMYRC-DOX micelles were assembled by amphiphilic dendrimers with the zwitterionic and targeting groups, which enhanced the therapeutic effect of DOX and reduced its side effects. The prepared targeting nanodrug has great potential for further application in antitumor therapy.

Role of Transcription Factor EB in Mitochondrial Dysfunction of Cisplatin-Induced Acute Kidney Injury.

Cisplatin, a widely used anticancer agent, can cause nephrotoxicity, including both acute kidney injury (AKI) and chronic kidney diseases, by accumulating in renal tubular epithelial cells (TECs). Mitochondrial pathology plays an important role in the pathogenesis of AKI. Based on the regulatory role of transcription factor EB (TFEB) in mitochondria, we investigated whether TFEB is involved in cisplatin-induced TEC damage. The results show that the expression of TFEB decreased in a concentration-dependent manner in both mouse kidney tissue and HK-2 cells when treated with cisplatin. A knockdown of TFEB aggravated cisplatin-induced renal TEC injury, which was partially reversed by TFEB overexpression in HK-2 cells. It was further observed that the TFEB knockdown also exacerbated cisplatin-induced mitochondrial damage in vitro, and included the depolarization of membrane potential, mitochondrial fragmentation and swelling, and the production of reactive oxygen species. In contrast, TFEB overexpression alleviated cisplatin-induced mitochondrial damage in TECs. These findings suggest that decreased TFEB expression may be a key mechanism of mitochondrial dysfunction in cisplatin-induced AKI, and that upregulation of TFEB has the potential to act as a therapeutic target to alleviate mitochondrial dysfunction and cisplatin-induced TEC injury. This study is important for developing therapeutic strategies to manipulate mitochondria through TFEB to delay AKI progression.

Generation of Sigmar1 conditional knockout mouse using CRISPR-Cas9 gene targeting.

The Sigma 1 receptor (SIGMAR1) is a transmembrane protein located in the mitochondria-associated endoplasmic reticulum membrane, and plays an important role in cell survival as a pluripotent modulator of a variety of signaling pathways related to neurodegeneration. Though SIGMAR1 is a potential target for neurodegenerative diseases, the specific role of SIGMAR1 in different tissue and cell types remains unclear. Here we reported the generation of Sigmar1 conditional knockout (Sigmar1loxP ) mice using CRISPR-Cas9 method to insert loxP sites into the 5'- and 3'-untranslated regions of Sigmar1. We showed that the insertion of loxP sequences did not affect the expression of Sigmar1 and that Sigmar1loxP/loxP mice exhibited no detectable visual defects compared with wild-type mice at the early adult stage. By crossing Sigmar1loxP mice with retina-specific Six3-Cre and ubiquitous CMV-Cre mice, we confirmed the deletion of Sigmar1 coding regions of exons 1-4, and the retina-specific and global loss of SIGMAR1 expression, respectively. Thus, Sigmar1loxP mice provide a valuable tool for unraveling the tissue and cell-type-specific role of Sigmar1.

Effect of long-term chronic hyperhomocysteinemia on retinal structure and function in the cystathionine-ß-synthase mutant mouse.

Elevated levels of the excitatory amino acid homocysteine (Hcy) have been implicated in retinal diseases in humans including glaucoma and macular degeneration. It is not clear whether elevated Hcy levels are pathogenic. Models of hyperhomocysteinemia (Hhcy) have proven useful in addressing this including mice with deficiency in the enzyme cystathionine ß-synthase (CBS). Cbs+/- mice have a ∼two-fold increase in plasma and retinal Hcy levels. Previous studies of visual function and structure in Cbs+/- mice during the first 10 months of life revealed mild ganglion cell loss, but minimal electrophysiological alterations. It is not clear whether extended, chronic exposure to moderate Hhcy elevation will lead to visual function loss and retinal pathology. The present study addressed this by performing comprehensive analyses of retinal function/structure in 20 month Cbs+/- and Cbs+/+ (WT) mice including IOP, SD-OCT, scotopic and photopic ERG, pattern ERG (pERG), and visual acuity. Eyes were harvested for histology and immunohistochemical analysis of Brn3a (ganglion cells), dihydroethidium (oxidative stress) and GFAP (gliosis). The analyses revealed no difference in IOP between groups for age/strain. Visual acuity measured ∼0.36c/d for mice at 20 months in Cbs+/- and WT mice; contrast sensitivity did not differ between groups at either age. Similarly SD-OCT, scotopic/photopic ERG and pERG revealed no differences between 20 month Cbs+/- and WT mice. There was minimal disruption in retinal structure when eyes were examined histologically. Morphometric analysis revealed no significant differences in retinal layers. Immunohistochemistry revealed ∼5 RGCs/100 µm retinal length in both Cbs+/- and WT mice at 20 months. While there was greater oxidative stress and gliosis in older (20 month) mice versus young (4 month) mice, there was no difference in these parameters between the 20 month Cbs+/- and WT mice. We conclude that chronic, moderate Hhcy (at least due to deficiency of Cbs) is not accompanied by retinal structural/functional changes that differ significantly from age-matched WT littermates. Despite considerable evidence that severe Hhcy is toxic to retina, moderate Hhcy appears tolerated by retina suggesting compensatory cellular survival mechanisms.

Controllable gelation of coordination nanocages from the physical interactions among surface grafted cholesteryl groups.

Coordination nanocage (CNC) incorporated gels have attracted enormous attention for the effective integration of micro-porosity, mechanical flexibility and processability; however, the understanding of their microscopic structure-property relationships remains unclear. Herein, CNCs with 24 surface grafted cholesterol groups are constructed precisely and their gelation can be manipulated upon the tunning of solvent polarities. Optically homogeneous organogels can be formed by introducing a certain amount of bad solvents into the solutions of hairy CNCs and the gelation can be reversed through temperature variation. Suggested from scattering and molecular dynamics studies, the solvophobic interaction-driven aggregation of cholesterol units contributes to the physical crosslinking of CNCs and finally the gelation of CNC solutions. The mechanical strength of the obtained gels is observed to be highly dependent on the flexibility of the organic linkers that bond the cholesterol units on the CNC surface. The effective interaction and dense packing of the cholesterol units in their aggregates highly rely on the degree of freedom of the cholesterol, which is controlled by the flexibility of the organic linkers that bond them on the CNC surface. The observed viscoelastic performance accompanied by the well-controlled mechanical strength of the organogels unambiguously demonstrates the potential for exploiting the synergistic physical correlations to fabricate novel functional materials from CNCs.

First-principles study of point defects in U3Si2: effects on the mechanical and electronic properties.

In recent years, U3Si2 has been proposed as an alternative nuclear fuel material to uranium dioxide (UO2) because of its intrinsically high uranium density and thermal conductivity. However, the operation environment in the nuclear reactor is complex and extreme, such as in-pile neutron irradiation, and thus it is necessary to explore the radiation response behavior of U3Si2 and the physical properties of its damaged states. In the present study, first-principles calculations based on density functional theory were carried out to investigate the mechanical and electronic properties of defective U3Si2. Our results showed that the defect stability in U3Si2, except its interstitial defects, is dependent on its chemical environment. When vacancy, antisite or interstitial defects are introduced into U3Si2, its elastic modulus are decreased and its ductility is enhanced. Although the presence of defects in U3Si2 does not change its metallic nature and the electron distribution in its Fermi level, their effect on the partial chemical bonding interaction is significant. This study suggests that under a radiation environment, the created defects in U3Si2 remarkably affect its mechanical and electronic properties.

Combined transcriptomic, proteomic and genomic analysis identifies reproductive-related proteins and potential modulators of female behaviors in Spodoptera litura.

The common cutworm, Spodoptera litura, is a polyandrous moth with high reproductive ability. Sexual reproduction is a unique strategy for survival and reproduction of population in this species. However, to date available information about its reproductive genes is rare. Here, we combined transcriptomics, genomics and proteomics approaches to characterize reproductive-related proteins in S. litura. Illumina sequencing in parallel with the reference genome led to the yields of 12,161 reproductive genes, representing 47.83% of genes annotated in the genome. Further, 524 genes of 19 specific gene families annotated in the genome were detected in reproductive tissues of both sexes, some of which exhibited sex-biased and/or tissue-enriched expression. Of these, manual efforts together with the transcriptome analyses re-annotated 54 odorant binding proteins (OBPs) and 23 chemosensory proteins (CSPs) with an increase of 18 OBPs and one CSP compared to those previously annotated in the genome. Interestingly, at least 35 OBPs and 22 CSPs were transcribed in at least one reproductive tissue, suggestive of their involvement in reproduction. Further proteomic analysis revealed 2381 common proteins between virgin and mated female reproductive systems, 79 of which were differentially expressed. More importantly, 74 proteins exclusive to mated females were identified as transferred relatives, coupled with their specific or high expression in male reproductive systems. Of the transferred proteins, several conserved protein classes across insects were observed including OBPs, serpins, trypsins and juvenile hormone-binding proteins. Our current study has extensively surveyed reproductive genes in S. litura with an emphasis on the roles of OBPs and CSPs in reproduction, and identifies potentially transferred proteins serving as modulators of female post-mating behaviors.

The ionotropic receptor gene family in Lepidoptera and Trichoptera: Annotation, evolutionary and functional perspectives.

Lepidoptera (moths and butterflies) and Trichoptera (caddisflies), belonging to the superorder Amphiesmenoptera, are the most diverse insect orders as representatives of the terrestrial and aquatic insects, respectively. The insects of the two orders possess different biological and behavioral characteristics, especially their larvae, presumably resulting in the differences of the ionotropic receptor (IR) genes in numbers, sequence characteristics or gene structure. Here, we employed genomics, transcriptomics, bioinformatics, phylogenetics and molecular biology strategies to characterize the IR gene repertoire in Lepidoptera and Trichoptera. Genome and transcriptome analyses with exhaustive homology-based searches and manual efforts, in 32 lepidopterans and five trichopterans, led to the identification of 1449 genes encoding IRs with 1170 full-length sequences, representing the most comprehensive set of chemoreceptor superfamilies across the Amphiesmenoptera. Analysis of gene gains and losses in orthologous groups implied that some IRs were lost in related species, and multiple gene copies occurred mainly in divergent IRs (D-IRs) by gene duplications. Phylogenetic analysis of 2442 IR proteins from 67 species revealed that Lepidoptera and Trichoptera IRs could be classified into three subfamilies, i.e., 14 antennal IRs (A-IRs), five Lepidoptera-specific IRs (LS-IRs) and four D-IRs. Of the three subfamilies, A-IRs and LS-IRs members within orthologous groups exhibited high conservation of gene structure, but D-IRs shared extremely low amino acid identities (below 30%). Expression profiles revealed functional diversities of IRs from Bombyx mori and Papilio xuthus involving smell, taste or reproduction, in which some genes displayed sex-biased expression in antennae associated with specific chemosensory behaviors of female or male adults. Our current study has provided insights into the evolution, conservation and divergence of IRs between/within Lepidoptera and Trichoptera, and allows for further experiments to investigate IR functions.

Role of Adiponectin in Cardiovascular Diseases Related to Glucose and Lipid Metabolism Disorders.

Lifestyle changes have led to increased incidence of cardiovascular disease (CVD); therefore, potential targets against CVD should be explored to mitigate its risks. Adiponectin (APN), an adipokine secreted by adipose tissue, has numerous beneficial effects against CVD related to glucose and lipid metabolism disorders, including regulation of glucose and lipid metabolism, increasing insulin sensitivity, reduction of oxidative stress and inflammation, protection of myocardial cells, and improvement in endothelial cell function. These effects demonstrate the anti-atherosclerotic and antihypertensive properties of APN, which could aid in improving myocardial hypertrophy, and reducing myocardial ischemia/reperfusion (MI/R) injury and myocardial infarction. APN can also be used for diagnosing and predicting heart failure. This review summarizes and discusses the role of APN in the treatment of CVD related to glucose and lipid metabolism disorders, and explores future APN research directions and clinical application prospects. Future studies should elucidate the signaling pathway network of APN cardiovascular protective effects, which will facilitate clinical trials targeting APN for CVD treatment in a clinical setting.

[Research progress on pharmacology of butylphthalide and its derivatives].

The butylphthalide(NBP), a colorless or light yellow viscous oily component isolated from celery seeds, has the effects of anti-inflammation, anti-oxidative stress, protecting blood-brain barrier, improving cerebral microcirculation, and promoting angiogenesis. It can protect the neurological function of patients with ischemic stroke through a variety of mechanisms, improve the symptoms of patients, and contribute to the long-term recovery of them. Therefore, independently developed in China, NBP was approved by State Food and Drug Administration for the clinical treatment of stroke patients in 2002. At the same time, owing to the complex multi-target pharmacological mechanism, NBP has been frequently used in clinical practice. As frequently verified, it has obvious effects in the treatment of other neurological diseases such as Alzheimer's disease, vascular dementia, Parkinson's disease, autoimmune diseases, depression, traumatic central nervous system injury. Moreover, it demonstrates significant pharmacological effects on non-neurological diseases such as diabetes mellitus and myocardial infarction. Therefore, this study summarizes the research progress on roles of NBP in nervous system diseases and non-nervous system diseases, and the pharmacological characteristics and mechanisms of NBP, which is expected to lay a basis for research on related targets.

Approaching Charge Separation Efficiency to Unity without Charge Recombination.

Improving the efficiency of charge separation (CS) and charge transport (CT) is essential for almost all optoelectronic applications, yet its maximization remains a big challenge. Here we propose a conceptual strategy to achieve CS efficiency close to unity and simultaneously avoid charge recombination (CR) during CT in a ferroelectric polar-discontinuity (PD) superlattice structure, as demonstrated in (BaTiO_{3})_{m}/(BiFeO_{3})_{n}, which is fundamentally different from the existing mechanisms. The competition of interfacial dipole and ferroelectric PD induces opposite band bending in BiFeO_{3} and BaTiO_{3} sublattices. Consequently, the photoexcited electrons (e) and holes (h) in individual sublattices move forward to the opposite interfaces forming electrically isolated e and h channels, leading to a CS efficiency close to unity. Importantly, the spatial isolation of conduction channels in (BaTiO_{3})_{m}/(BiFeO_{3})_{n} enable suppression of CR during CT, thus realizing a unique band diagram for spatially orthogonal CS and CT. Remarkably, (BaTiO_{3})_{m}/(BiFeO_{3})_{n} can maintain a high photocurrent and large band gap simultaneously. Our results provide a fascinating illumination for designing artificial heterostructures toward ideal CS and CT in optoelectronic applications.

Optimal timing for activation of sigma 1 receptor in the Pde6brd10/J (rd10) mouse model of retinitis pigmentosa.

Sigma 1 Receptor (Sig1R), a pluripotent modulator of cell survival, is a promising target for treatment of retinal degenerative diseases. Previously, we reported that administration of the high-affinity, high-specificity Sig1R ligand (+)-pentazocine, ((+)-PTZ) beginning at post-natal day 14 (P14) and continuing every other day improves visual acuity and delays loss of photoreceptor cells (PRCs) in the Pde6ßrd10/J (rd10) mouse model of retinitis pigmentosa. Whether administration of (+)-PTZ, at time points concomitant with (P18) or following (P21, P24) onset of PRC death, would prove neuroprotective was investigated in this study. Rd10 mice were administered (+)-PTZ intraperitoneally [0.5 mg/kg], starting at either P14, P18, P21 or P24. Injections continued every other day through P42. Visual acuity was assessed using the optokinetic tracking response (OKR). Rd10 mice treated with (+)-PTZ beginning at P14 retained visual acuity for the duration of the study (~0.33 c/d at P21, ~0.38 c/d at P28, ~0.32 c/d at P35, ~0.32 c/d at P42), whereas mice injected beginning at P18, P21, P24 showed a decline in acuity when tested at P35 and P42. Their acuity was only slightly better than rd10-non-treated mice. Electrophysiologic function was assessed using scotopic and photopic electroretinography (ERG) to assess rod and cone function, respectively. Photopic a- and b-wave amplitudes were significantly greater in rd10 mice treated with (+)-PTZ beginning at P14 compared with non-treated mice and those in the later-onset (+)-PTZ injection groups. Retinal architecture was visualized in living mice using spectral domain-optical coherence tomography (SD-OCT) allowing measurement of the total retinal thickness, the inner retina and the outer retina (the area most affected in rd10 mice). The outer retina measured ~35 µm in rd10 mice treated with (+)-PTZ beginning at P14, which was significantly greater than mice in the later-onset (+)-PTZ injection groups (~25 µm) and non-treated rd10 mice (~25 µm). Following the visual function studies performed in the living mice, eyes were harvested at P42 for histologic analysis. While the inner retina was largely intact in all (+)-PTZ-injection groups, there was a marked reduction in the outer retina of non-treated rd10 mice (e.g. in the outer nuclear layer there were ~10 PRCs/100 µm retinal length). The rd10 mice treated with (+)-PTZ beginning at P14 had ~20 PRCs/100 µm retinal length, whereas the mice in groups beginning P18, P21 and P24 had ~16 PRCs/100 µm retinal length. In conclusion, the data indicate that delaying (+)-PTZ injection past the onset of PRC death in rd10 mice - even by a few days - can negatively impact the long-term preservation of retinal function. Our findings suggest that optimizing the administration of Sig1R ligands is critical for retinal neuroprotection.