Monitoring Cavefish Populations and Environmental Quality in Cave Springs Cave, Arkansas

Cave Springs Cave, Benton County, Arkansas, was monitored from October 1997 to June 1998 to determine the chemical and physical environmental quality and the status of the population of threatened Ozark cavefish, Amblyopsis rosae. The majority of the chemical parameters measured were indicative of adequate environmental quality in the Cave Springs Cave ecosystem. However, several significant problems were revealed. A trend analysis of known water quality studies of this cave complex suggests that many organic and inorganic chemicals have increased in concentration in the last 14 years. This ecologically sensitive water body did not meet Arkansas water quality regulations for fecal coliform densities, and copper, selenium, and lead concentrations exceeded limits for exposure to aquatic life. The geometric mean total coliform count for base flows was 500 MPN/100ml, and during the March storm event, coliform densities exceeded 20,000 MPN/100ml. When compared to the national primary drinking water regulations, this spring water exceeds the maximum contaminant levels (MCL) for turbidity, nitrite, total coliforms, and Escherichia coli, and approaches the MCL’s for copper and zinc. During the March storm event, Escherichia coli densities exceeded 5,000 MPN/100ml. During the June storm event, nitrite levels reached 2 mg/L, twice the MCL for national drinking water standards. Nitrite toxicity is known to cause severe anemia in fishes and damage their tissues. One semi-volatile organic, Di (2-ethylhexyl) phthalate (DEHP), was found in significant concentration (500 ug/kg) in resident crayfish tissue. DEHP is known to bioaccumulate in fish tissue, and cause reproductive damage and reduced fertility in fish. A visual survey was performed on January 25, 1998, and 106 cavefish were sighted. This survey indicated a 30% decline in the Cave Springs Cave population. A comparison of base-flow sampling results at two different locations -- upstream and downstream of bat rookeries -- indicates that the majority of coliform bacteria are not attributed to bat guano. These findings suggest that bacteria are being imported into the cave stream from the recharge zone. The high nitrite, total coliform, and E. coli counts suggest that septic system leakage or the land application of animal waste is involved. Continued water quality monitoring and surveys of the Ozark cavefish population are recommended. Future monitoring should focus on storm events and parameters that measure pollutants originating from the recharge zone and their effect on the cave ecosystem. As well, investigation into the nature of the pollutants from the recharge zone is suggested

Ultrafast Transfer and Transient Entrapment of Photoexcited Mg Electron in Mg@C-60

Electron relaxation is studied in endofullerene Mg@C-60 after an initial localized photoexcitation in Mg by nonadiabatic molecular dynamics simulations. Two approaches to the electronic structure of the excited electronic states are used: (i) an independent particle approximation based on a density-functional theory description of molecular orbitals and (ii) a configuration-interaction description of the many-body effects. Both methods exhibit similar relaxation times, leading to an ultrafast decay and charge transfer from Mg to C-60 within tens of femtoseconds. Method (i) further elicits a transient trap of the transferred electron that can delay the electron-hole recombination. Results shall motivate experiments to probe these ultrafast processes by two-photon transient absorption or photoelectron spectroscopy in gas phase, in solution, or as thin films

Effect of Raw and Extruded Propionic Acid-Treated Field Beans on Energy and Crude Protein Digestibility (In-Vitro and In-Vivo), Growth and Carcass Quality in Grow-Finisher Pigs

The in-vitro ileal digestibility of dry matter (DM), organic matter (OM), and crude protein (CP) of field beans treated with propionic acid (trFB) and extruded trFB (exFB) was determined in experiment 1. The DE and dCP values of trFB and exFB were determined using the difference method in experiment 2. The effect of replacing SBM with trFB and exFB in grow-finisher diets on growth, carcass quality, apparent ileal digestibility (AiD), and total tract digestibility (ATTD) of DM, OM, gross energy (GE), and CP were investigated in experiment 3. In exp. 1, in-vitro digestibility of exFB compared to trFB was unchanged for DM (p = 0.12), increased for OM (p 0.05).info:eu-repo/semantics/publishedVersio

Photoinduced Vibrations Drive Ultrafast Structural Distortion in Lead Halide Perovskite

The success of organic–inorganic perovskites in optoelectronics is dictated by the complex interplay between various underlying microscopic phenomena. The structural dynamics of organic cations and the inorganic sublattice after photoexcitation are hypothesized to have a direct effect on the material properties, thereby affecting the overall device performance. Here, we use ultrafast heterodyne-detected two-dimensional (2D) electronic spectroscopy to reveal impulsively excited vibrational modes of methylammonium (MA) lead iodide perovskite, which drive the structural distortion after photoexcitation. Vibrational analysis of the measured data allows us to monitor the time-evolved librational motion of the MA cation along with the vibrational coherences of the inorganic sublattice. Wavelet analysis of the observed vibrational coherences reveals the coherent generation of the librational motion of the MA cation within ∼300 fs complemented with the coherent evolution of the inorganic skeletal motion. To rationalize this observation, we employed the configuration interaction singles (CIS), which support our experimental observations of the coherent generation of librational motions in the MA cation and highlight the importance of the anharmonic interaction between the MA cation and the inorganic sublattice. Moreover, our advanced theoretical calculations predict the transfer of the photoinduced vibrational coherence from the MA cation to the inorganic sublattice, leading to reorganization of the lattice to form a polaronic state with a long lifetime. Our study uncovers the interplay of the organic cation and inorganic sublattice during formation of the polaron, which may lead to novel design principles for the next generation of perovskite solar cell materials

A multicomponent reaction platform towards multimodal near-infrared BODIPY dyes for STED and fluorescence lifetime imaging

We report a platform combining multicomponent reaction synthesis and automated cell-based screening to develop biocompatible NIR-BODIPY fluorophores. From a library of over 60 fluorophores, we optimised compound NIRBD-62c as a multimodal probe with suitable properties for STED super-resolution and fluorescence lifetime imaging. Furthermore, we employed NIRBD-62c for imaging trafficking inside cells and to examine how pharmacological inhibitors can alter the vesicular traffic between intracellular compartments and the plasma membrane

Novel Fluorescent Labeled Octasilsesquioxanes Nanohybrids as Potential Materials for Latent Fingerprinting Detection

The recent demand for fluorescent labeled materials (FLMs) in forensic security concepts such as latent fingerprints (LFs) that encodes information for anti-counterfeiting and encryption of confidential data makes necessary the development of building new and innovative materials. Here, novel FLMs based on Polyhedral Oligomeric Silsesquioxanes (POSS) functionalized with fluorophores via “click” reactions have been successfully synthesized and fully characterized. A comprehensive study of their photophysical properties has displayed large Stokes’s shift together with good photostability in all cases, fulfilling the fundamental requisites for any legible LF detection on various surfaces. The excellent performance of the hetero-bifunctional FLM in the visualization of LF is emphasized by their legibility, selectivity, sensitivity and temporal photostability. In this study, development mechanisms have been proposed and the overall concept constitute a novel approach for vis-à-vis forensic investigations to trace an individual’s identity.Alexander von Humboldt FoundationGeneralitat ValencianaUniversität RegensburgUniversidad de La LagunaMinisterio de Ciencia, Innovación y Universidade

Estudio de la eficacia de una vacuna frente a la Lactococosis de la trucha arco iris (Oncorhynchus mykiss) a diferentes temperaturas.

Lactococcus garvieae es el agente etiológico de la Lactococosis, considerada actualmente comouna enfermedad emergente responsable de graves pérdidas económicas tanto en acuiculturacontinental como marina cuando la temperatura del agua supera los 16ºC. En la actualidad, lavacunación con vacunas inactivadas se ha establecido como el método más eficaz para controlarel proceso.En el presente trabajo hemos evaluado la eficacia de una vacuna comercial (Icthiovac-Lg) frentea una infección experimental con L. garvieae en trucha arco iris (Oncorhynchus mykiss) habiendovacunado los peces a diferentes temperaturas del agua.Dos grupos de 50 truchas de 30-35 g de peso fueron vacunadas a temperaturas de 8 y 15ºCrespectivamente. Fueron mantenidas en estas condiciones junto con otras 50 truchas más sinvacunar en cada grupo durante 30 días, momento en el cual se procedió a realizar una infecciónexperimental vía intraperitoneal con una cepa patógena de L. garvieae. Los peces se mantuvieronen observación durante 21 días más. Al final del estudio se obtuvo un valor de RPS (PorcentajeRelativo de Supervivencia) para el grupo vacunado a temperatura alta de 96% mientras quepara el grupo vacunado a 8ºC fue de 83%

Ultrafast electron diffraction imaging of bond breaking in di-ionized acetylene

Visualizing chemical reactions as they occur requires atomic spatial and femtosecond temporal resolution. Here, we report imaging of the molecular structure of acetylene (C2H2) 9 femtoseconds after ionization. Using mid-infrared laser–induced electron diffraction (LIED), we obtained snapshots as a proton departs the [C2H2]2+ ion. By introducing an additional laser field, we also demonstrate control over the ultrafast dissociation process and resolve different bond dynamics for molecules oriented parallel versus perpendicular to the LIED field. These measurements are in excellent agreement with a quantum chemical description of field-dressed molecular dynamicsPostprint (author's final draft