Unveiling the Chemical Diversity of the Deep-Sea Sponge Characella pachastrelloides

Sponges are at the forefront of marine natural product research. In the deep sea, extreme conditions have driven secondary metabolite pathway evolution such that we might expect deep-sea sponges to yield a broad range of unique natural products. Here, we investigate the chemodiversity of a deep-sea tetractinellid sponge, Characella pachastrelloides, collected from ~800 m depth in Irish waters. First, we analyzed the MS/MS data obtained from fractions of this sponge on the GNPS public online platform to guide our exploration of its chemodiversity. Novel glycolipopeptides named characellides were previously isolated from the sponge and herein cyanocobalamin, a manufactured form of vitamin B12, not previously found in nature, was isolated in a large amount. We also identified several poecillastrins from the molecular network, a class of polyketide known to exhibit cytotoxicity. Light sensitivity prevented the isolation and characterization of these polyketides, but their presence was confirmed by characteristic NMR and MS signals. Finally, we isolated the new betaine 6-methylhercynine, which contains a unique methylation at C-2 of the imidazole ring. This compound showed potent cytotoxicity towards against HeLa (cervical cancer) cells.

Floating Gate Negative Capacitance MoS2 Phototransistor with High Photosensitivity

Monolayer MoS2 exhibits interesting optoelectronic properties that have been utilized in applications such as photodetectors and light emitting diodes. For image sensing applications, improving the light sensitivity relies on achieving...

Microperimetry in Children’s Practice

Child health is a global health priority. The program “Elimination of Eliminable Blindness in the World of Vision-2020” gives the fourth place to the problems of pediatric ophthalmopathology and creates targeted programs for their elimination. The introduction of modern equipment in the clinical practice of pediatric ophthalmologists has expanded the boundaries of traditional diagnostics. Microperimetry is an innovative, quantitative, non-invasive diagnostic study aimed at assessing the functional ability of the retina in strict correlation with morphology. Along with the assessment of light sensitivity, the device allows you to measure fixation parameters, which serves as a reliable criterion for its stability and indirectly reflects the functional organization of central vision. In this regard, the literature review presents the results of domestic and foreign researchers who used microperimetric testing as the main or additional research method for diseases of various etiologies, such as hereditary retinal diseases, amblyopia, and nystagmus. Most authors have demonstrated the high diagnostic significance of this method, the ability to assess photosensitivity of the retina, the detection of fixation disorders, such as eccentricity and instability, even in pediatric patients. The use of microperimetry as a new method of treatment for these diseases has also been shown. Visual rehabilitation based on biofeedback provided by this device has shown high efficiency in diseases of the central region. More research remains to be done to determine future potential applications of this technology, in particular in pediatric practice, and to develop the potential of microperimetry as a tool for the visual rehabilitation of patients.

Phototransduction in Anuran Green Rods: Origins of Extra-Sensitivity

Green rods (GRs) represent a unique type of photoreceptor to be found in the retinas of anuran amphibians. These cells harbor a cone-specific blue-sensitive visual pigment but exhibit morphology of the outer segment typical for classic red rods (RRs), which makes them a perspective model object for studying cone–rod transmutation. In the present study, we performed detailed electrophysiological examination of the light sensitivity, response kinetics and parameters of discrete and continuous dark noise in GRs of the two anuran species: cane toad and marsh frog. Our results confirm that anuran GRs are highly specialized nocturnal vision receptors. Moreover, their rate of phototransduction quenching appeared to be about two-times slower than in RRs, which makes them even more efficient single photon detectors. The operating intensity ranges for two rod types widely overlap supposedly allowing amphibians to discriminate colors in the scotopic region. Unexpectedly for typical cone pigments but in line with some previous reports, the spontaneous isomerization rate of the GR visual pigment was found to be the same as for rhodopsin of RRs. Thus, our results expand the knowledge on anuran GRs and show that these are even more specialized single photon catchers than RRs, which allows us to assign them a status of “super-rods”.

Pain Following Endoscopic Foreheadplasty Surgery in Women

Background Endoscopic foreheadplasty surgery (EFS) is a common procedure, however little evidence exists describing the nature or treatment of postoperative headache pain and associated symptoms. Objectives Our objective was to describe the intensity, quality, location, and duration of headache pain in women following EFS. We also compared post EFS symptoms with migraine, described medication use and efficacy, and measured emotional and functional outcomes. Methods This descriptive study used an observational repeated measures design. Forty-two women (age mean±std=59.0±7.9 years) undergoing EFS were prospectively recruited from twelve private cosmetic practices in three California counties. Phone interviews with the Acute Short-Form 12v2, and Headache Questionnaires were conducted on postoperative days (POD) 1, 3, 7, and 30. Results At POD#1, 93% reported at least moderate pain and 64% severe pain. Severe pain was characterized as throbbing (71%), sharp (53%), dull (76%), exploding (41%), imploding (53%), continuous (53%) or intermittent (41%) on POD#1. Moderate pain was most frequent on POD#3 (21%) compared to POD#1 (19%), POD#7 and #30 (12%). Mild pain predominated on POD#3 (40%) and POD#7 (40%), with (20%) remaining on POD#30. The majority (79%) of post EFS symptoms commonly included light sensitivity and nausea, and therefore met most International Classification of Headache Disorders criteria for migraine. Analgesic use provided inconsistent relief. Functional and emotional status did not return to baseline throughout the 30-day postoperative period. Conclusions Immediately following EFS, most women experience moderate to severe headache pain, despite use of medications. Pain persists in many patients for up to a month. Headache is associated with migraine symptoms, including light sensitivity and nausea.

Simple and cheap photosystem for herbarium digitization

The digitization of the natural history collections is a crucial task of today. It allows not only sharing the data but also virtually preserving the specimens. This is especially important for small collections that suffer from limited financial support and can be easily lost. Here we share our experience of the building of cheap and simple photosystem that can be used for routine digitization of local herbaria with low or without incomes. This photosystem is modular and based on the regular components that can be easily purchased and/or updated. It is compact and can be conveniently assembled and disassembled, and transported. This photosystem consists of horizontal tripod Beike Q999H with two led lamps Yongnuo YN-300 Air mounted on the 11” Magic Arm handles. The camera Canon EOS 800D was chosen due to presence of fully rotated display, the high resolution, modern focusing system, RAW format support, and low price on the market. The lens Tokina AT-X M35 PRO DX AF 35 mm f/2.8 Macro was chosen due to extreme sharpness along the whole capturing field, low aberrations and optical distortion, high light sensitivity, and fast autofocus. We also tested light box as an option for herbarium specimens’ digitization. However, we found that light box is inconvenient for herbarium digitization dues several reasons, among which its massive sizes, limited access to working space, and necessity of application of huge mounting system that should hold the camera far higher over the center of light box. In general, work with light box significantly decelerated the digitization process. We did not find any advantaged in use of the light box and therefore it was rejected. We hope that our experience will be useful for other curators wanting to digitize their collections and having limited budget.

Structural, Optical and Electrical Characterizations of Cr-doped CuO Thin Films

The polycrystalline copper oxide (CuO) thin films have been produced using method of spin coating onto the soda lime glass (SLG) as well as substrate of p-type Si (1 0 0) wafers at 500 ºC in furnace. The obtained undoped and Cr doped thin films of CuO have been comprehensively characterized via X-ray diffraction (XRD), ultraviolet–vis (UV–vis) spectroscopy, the current–voltage ( I – V ) and capacitance–voltage ( C – V ) characteristics for providing information on quality of the crystalline nature, change in energy band gap and electrical properties, respectively. Structural analysis results which obtained from XRD data demonstrate that CuO films conjunction with Cr doping indicated that all thin films have monoclinic polycrystalline nature, with two main peaks (002) and (111) with d hkl about 2.52 and 2.32 Å, respectively. The transmittance and energy band gap value of undoped and Cr doped thin films of CuO ranging in varying concentration ratio have been determined in the wavelength region of 300 to 1100 nm. UV–vis spectrum analysis results indicate that both transmittance value and energy band gap of the CuO films is changed with increasing Cr doping ratio in CuO solution at room temperature. The I–V and C–V characteristic of Cr:CuO/p-Si diodes were associated with the CuO/p-Si diodes. It is seen that doping of Cr had a significant change onv the obtained devices’ performance. Thus, the Cr:CuO/p-Si diodes generated by 1% Cr doping using spin coating method had the highest light sensitivity compared with those of the other diodes.

The importance of doping TiO2 into polypyrrol nanofibers to improve their optical sensitivity

In this study Electrochemical polymerization was used to make polypyrrol nanofiber. The in situ chemical oxidative polymerization approach was used to create a nanocomposite of polypyrrole PPy-TiO2. To achieve homogeneous dispersion inside the PPy matrix, the TiO2 was dissolved and ultrasonically dispersed. The surface morphology of polypyrrol and PPy/TiO2 nanocomposites was studied using field emission scanning electron microscopy (FE-SEM), which revealed of a polypyrrol nanofibre network and showed that the TiO2 nanoparticles was well incorporated. The produced PPy/TiO2 nanocomposite was characterized using XRD (X-Ray diffraction) and FT-IR (Fourier Transform Infrared). The formation of TiO2 nanoparticales on a PPy layer matrix was discovered, as well as homogeneous dispersion of TiO2 inside the PPy matrix and considerable interaction between PPy and TiO2. The produced PPy/TiO2 nanocomposite sensors’ response was investigated towards of light-power sensitivity. The PPy/TiO2 synergistic effects improve the light sensitivity qualities of the photodetector. The maximium sensitivity of PPy/TiO2 was around (188 %) at 20% TiO2 concentration at a light power of 30 mW for a laser diode 720 nm, while the rise time and fall time was ≈ 2.5sec.

Cryo-EM structures of the channelrhodopsin ChRmine in lipid nanodiscs

Microbial channelrhodopsins are light-gated ion channels widely used for optogenetic manipulation of neuronal activity. ChRmine is a bacteriorhodopsin-like cation channelrhodopsin (BCCR) more closely related to ion pump rhodopsins than other channelrhodopsins. ChRmine displays unique properties favorable for optogenetics including high light sensitivity, a red-shifted activation spectrum, cation selectivity, and large photocurrents while its slow closing kinetics impede some applications. The structural basis for ChRmine function, or that of any other BCCR, is unknown. Here, we present cryo-EM structures of ChRmine in lipid nanodiscs in apo (opsin) and retinal-bound (rhodopsin) forms. The structures reveal an unprecedented trimeric architecture with a lipid filled central pore. Large electronegative cavities on either side of the membrane facilitate high conductance and selectivity for cations over protons. The retinal binding pocket structure suggests spectral and kinetic properties could be tuned with mutations and we identify ChRmine variants with two-fold increased and ten-fold decreased closing rates. These results provide insight into structural features that generate an ultra-potent microbial opsin and provide a platform for rational engineering of channelrhodopsins with improved properties that could expand the scale, depth, and precision of optogenetic manipulations.