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Large-scale studies of the spatial and temporal variation of groundwater drought status require complete inventories of groundwater levels on regular time steps from many sites so that a standardised drought index can be calculated for each site. However, groundwater levels are often measured sporadically, and inventories include missing or erroneous data. A flexible and efficient modelling framework is developed to fill gaps and regularise data in such inventories. It uses linear mixed models to account for seasonal variation, long-term trends and responses to precipitation and temperature over different temporal scales. The only data required to estimate the models are the groundwater level measurements and freely available gridded weather products. The contribution of each of the four types of trends at a site can be determined and thus the causes of temporal variation of groundwater levels can be interpreted. Validation reveals that the models explain a substantial proportion of groundwater level variation and that the uncertainty of the predictions is accurately quantified. The computation for each site takes less than 130 s and requires little supervision. Hence, the approach is suitable to be upscaled to represent the variation of groundwater levels in large datasets consisting of thousands of boreholes.

Hospital revenues generated by diagnosis-related groups (DRGs) are in part dependent on the coding of secondary diagnoses. Therefore, more and more hospitals trust specialized coders with this task, thereby relieving doctors from time-consuming administrative burdens and establishing a highly professionalized coding environment. However, it is vastly unknown if the revenues generated by the coders do indeed exceed their incurred costs.Coding data from the departments of dermatology, ophthalmology, and infectious diseases from Rostock University Hospital from 2007-2016 were analyzed for the effects of secondary diagnoses on the resulting DRG, i. e., hospital charges.Ophthalmological case were highly resistant to the addition of secondary diagnoses. In contrast, adding secondary diagnoses to cases from infectious diseases resulted in 15% higher revenues. Although dermatological and infectious cases share the same sensitivity to secondary diagnoses, higher revenues could only rarely be realized in dermatology, probably owing to a younger, less multimorbid patient population.Except for ophthalmology, trusting specialized coders with clinical coding generates additional revenues through the coding of secondary diagnoses which exceed the costs for employing these coders.

This paper describes an instrument capable of studying diffuse reflection of mid-infrared (mid-IR) photons on ultrafast time scales. Femtosecond mid-IR pulses are generated by difference frequency mixing the output of an optical parametric amplifier that is pumped using a regeneratively amplified Ti:Sapphire laser. Time resolution is achieved by up-converting the diffusely reflected photons with pulses from the Ti:Sapphire oscillator. Experiments were performed on a series of powdered KBr samples containing varying amounts of carbon black. The results suggest that diffusely reflected mid-IR photons fall into two distinct categories. A small fraction of the photons travel relatively long effective path lengths (1.3–2.3 mm), while the majority traverse a much shorter distance (0.2–0.05 mm).

Almost exclusively, lineshape functions used to model infrared (IR) absorption peaks are based on symmetric frequency distributions. However, in complex systems such as large biological macromolecules in aqueous solutions, the distribution of vibrational frequencies may in fact be asymmetric. In this communication, we show that asymmetry can be introduced to the standard symmetric Lorentzian and Gaussian lineshapes using a simple, easy to implement method. Our technique involves replacing the static width parameter of the symmetric profiles with a smoothly varying function that is wave number dependent. In this way, the width varies across the IR band resulting in an asymmetric peak. In our model, the width varies sigmoidally with wave number. As a demonstration, we fit experimental spectra of adenosine 5′-monophosphate (AMP).

The work presented in this paper details the design and performance characteristics of a new hyperspectral visible imaging technique. Rather than using optical filters or a dispersing element, this design implements Fourier transform spectroscopy to achieve spectral discrimination. One potentially powerful application of this new technology is the nondestructive analysis and authentication of written and printed documents. Document samples were prepared using red, blue, and black inks. The samples were later altered using a different ink of the same color. While the alterations are undetectable to the naked eye, the alterations involving the blue and black inks were easily detected when the spectrally resolved images were viewed. Analysis of the sample using the red inks was unsuccessful. A 2004 series $20 bill was imaged to demonstrate the application to document authentication. The results argue that counterfeit detection and quality control during printing are plausible applications of Fourier transform hyperspectral visible imaging. All of the images were subjected to fuzzy c-means cluster analysis in an effort to objectively analyze and automate image analysis. Our results show that cluster analysis can distinguish image features that have remarkably similar visible transmission spectra.

Die Neutrophile Dermatose der Handrucken (NDDH) ist eine lokalisierte Form eines Sweet-Syndroms. Das klinische Bild ist charakterisiert durch auf die Handrucken begrenzte livide Papeln und Plaques. Das histologische Korrelat ist ein dichtes, neutrophilenreiches Infiltrat im oberen Korium. In uber 50 % der Falle ist die NDDH mit einer zugrunde liegenden Erkrankung assoziiert. Insbesondere maligne hamatologische Grunderkrankungen und chronisch entzundliche Darmerkrankungen sollten bedacht werden.

Second and third generation Newkome-type trifurcated dendrimers, containing either a coumarin or dansyl fluorescent probe at the dendrimer core, have been synthesized and attached to ArgoGel ® solid-phase-synthesis beads. Subsequent reaction with rhodamine dye shows that the dye can penetrate throughout the beads to acylate the remaining sites. Thus, it is possible to achieve a spatially resolved microdomain for library formation at the core of the dendrimer, primarily on the bead's periphery, and a second microdomain suitable for derivatization by other reagents such as encoding tags and fluorescent sensors.

Picosecond and nanosecond dynamics in the interior of DNA are observed for the first time as a dynamic Stokes shift in the fluorescence of a specially designed base-pair analogue. A recently synthesized coumarin C-riboside has been incorporated into an oligonucleotide in place of a normal purine·pyrimidine base pair. The dynamic Stokes shift of this probe occurs with components near 300 ps and 13 ns. These times are too long for solvent relaxation or simple vibrational motion of the DNA framework. They imply that the interior of DNA is a unique dynamic environment unlike either a fluid or a molecular crystal.

For the first time, the static and dynamic properties of the interior of DNA have been measured through their effects on the Stokes shift of an intercalated dye. Fluorescence excitation and emissio...

The trimetallic complexes [{(bpy)(2)M(dpp)}(2)Ru(dpq)](6+) (M = Ru(II) or Os(II), bpy = 2,2'-bipyridine, dpp = 2,3-bis(2-pyridyl)pyrazine, and dpq = 2,3-bis(2-pyridyl)quinoxaline) have been prepared and the details of their spectroscopic, electrochemical, and spectroelectrochemical properties investigated. These mixed bridging ligand complexes are a new group of synthons that can be useful for the construction of supramolecular devices for a wide variety of functions. It is the presence of the terminal dpq ligand that allows for their incorporation into larger supramolecular systems. This dpq ligand serves as an acceptor ligand that will possess a lower lying pi orbital than the dpp ligands once these chromophores are incorporated into larger systems. The [{(bpy)(2)M(dpp)}(2)Ru(dpq)](6+) systems display overlapping terminal metal oxidations at 1.66 and 1.18 V vs Ag/AgCl for the Ru and Os systems, respectively. This indicates that within this framework, these terminal, M, metals are largely electronically uncoupled. No oxidative process for the central Ru metal center is observed within our solvent window. The [{(bpy)(2)M(dpp)}(2)Ru(dpq)](6+) systems have M --dpp charge transfer (CT) lowest lying excited states. The [{(bpy)(2)Ru(dpp)}(2)Ru(dpq)](6+) Ru --dpp CT state displays an emission centered at 775 nm with a lifetime of 65 ns at room temperature in deoxygenated CH(3)CN solution. The details of the electrochemical, spectroscopic, and spectroelectrochemical studies of these supramolecular light absorbers and the dichloro synthons, [{(bpy)(2)M(dpp)}(2)RuCl(2)](4+), are reported herein.

Using infrared (IR) absorption spectroscopy, we have explored the folding thermodynamics of the UNCG class of RNA hairpin tetraloops (N = U, A, C, or G). Without the need to introduce non-native probes, IR spectroscopy makes it possible to distinguish specific structural elements such as base pairing versus base stacking or loop versus stem motions. Our results show that different structural components exhibit different thermodynamics. Specifically, we have found that tetraloop melting proceeds in a thermally sequential fashion, where base pairing in the stem is disrupted before (i.e., at a lower temperature) base stacking along the entire chain. In addition, for N = A, our data argue that the structure immediately surrounding adenine is particularly stable and melts at a higher temperature than either base-pairing or base-stacking interactions. Taken together, these results suggest that hairpin loop formation is not a simple two-state process, even in the equilibrium limit.

Probing a sample using infrared spectroscopy following a laser-induced temperature jump is a powerful method to monitor fast relaxation kinetics. Here, we describe how this approach is used to study the kinetics of RNA folding. We begin with a concise summary of the infrared spectral properties of RNA in the 1500–1800 cm − 1 region. The infrared transitions in this region are directly related to the double bond stretching vibrations and ring modes of the nucleotide bases. When RNA undergoes a conformational change, the local environments of the nucleotides are altered. Consequently, the changes in the corresponding infrared spectrum are associated with the structural changes. Experimentally, temperature is used to systematically vary the RNA structure. When a short laser pulse is used to produce a rapid temperature increase in the sample, the structural changes that ensue can be followed in real time. In this contribution, we discuss experimental methods including sample preparation, instrumentation, and data analysis. We conclude with several experimental examples that highlight usefulness of the technique.

We have studied the fast relaxation kinetics of a small RNA hairpin tetraloop using time-resolved infrared spectroscopy. A laser-induced temperature jump initiated the relaxation by rapidly perturbing the thermal equilibrium of the sample. We probed the relaxation kinetics at two different wavenumbers, 1574 and 1669 cm (-1). The latter is due to the C6O6 carbonyl stretch of the base guanine and is a direct measure of guanine base pairing. The former is assigned to a ring vibration of guanine and tracks structure by sensing base stacking interactions. Overall, the kinetics at 1574 cm (-1) are faster than those observed at 1669 cm (-1). When relaxation occurs at the melting temperature, the kinetics at both wavenumbers are biexponential. When relaxation occurs at a temperature that is higher than the melting temperature, the data at 1669 cm (-1) are still biexponential while only a single fast phase is resolved in the data at 1574 cm (-1). The fast phases are in the range of microseconds, while the slower phases are in the range of tens of microseconds. At both wavenumbers, a portion of the relaxation is not resolved, indicating the existence of a very fast, sub-100 ns phase. Our results provide additional evidence that small, fast folding hairpin loops are characterized by a rugged energy landscape. Furthermore, our data suggest that single-strand stacking interactions and stacking interactions in the loop contribute significantly to the ruggedness of the energy landscape. This work also demonstrates the utility of time-resolved infrared spectroscopy in studying RNA folding.

A series of new polymetallic complexes have been prepared which couple d6 pseudooctahedral lightabsorbing centers to a d8 square planar platinum site. These systems have lowest lying excited states that are M → BL charge transfer in nature. Hence, optical excitation directs charge flow toward the coupled platinum site. Synthetic variation of the lightabsorbing metal and the bridging ligand has been quite useful in the interpretation of the spectroscopic and electrochemical properties of these systems.

Time-resolved Stokes shift measurements of the local structural relaxation of three DNA oligonucleotides are presented. Logarithmic relaxation is seen for over three decades in time (40 ps-40 ns), indicating a complex relaxation among a large number of conformational substates. The observed relaxation is the same in all the sequences. Sequence dependence of the localized dynamics of DNA does not appear within this time range. We infer that 30%-50% of the relaxation is faster than 40 ps, has a nonlogarithmic decay and has a sequence dependent amplitude.

A new type of mixed-metal, supramolecular complex has been designed that incorporates a platinum center to allow binding to DNA. The interaction of two such platinum heterobimetallic complexes of the general formula [(bpy)(2)M(dpb)PtCl(2)]Cl(2) (M = Ru(II), Os(II); bpy = 2,2'-bipyridine; dpb = 2,3-bis(2-pyridyl)benzoquinoxaline) with DNA is reported herein. The modular design of these systems allows for synthetic variation of individual components within this structural motif. In this case, the remote metal is varied from Ru(II) to Os(II). DNA binding was analyzed using non-denaturing agarose gel electrophoresis. The interaction of these complexes with DNA was studied relative to the known DNA cross-linkers, cis-[Pt(NH(3))Cl(2)] (cisplatin) and trans-{[PtCl(NH(3))(2)](2)(mgr;-H(2)N(CH(2))(6)NH(2))}(2+) (1,1/t,t). Our mixed-metal Ru,Pt and Os,Pt compounds retard the migration of DNA through the gel in both a concentration- and time-dependent manner. Their effect on the migration of DNA is similar to, although much more dramatic than, that observed for either cisplatin or 1,1/t,t. Our evidence suggests a covalent binding of our mixed-metal complexes to DNA through the platinum site. The degree of retardation of DNA migration suggests a large change in DNA conformation is induced by binding of our mixed-metal complexes. This work establishes these inorganic systems as a new class of DNA-binding agents and lays the groundwork for future efforts to enhance binding in an effort to develop novel anticancer drugs through serial design and testing.

A DNA base pair has been replaced by a coumarin, and the DNA’s “solvation” dynamics monitored by time-resolved Stokes shift measurements. The shift is logarithmic in time, indicating an extremely broad distribution of relaxation times.

A cw CO 2 laser with a power of 200 W has been used to evaporate thin multilayer films of HfO 2 SiO 2 and ZrO 2 SiO 2 . Higher values of laser damage resistance were found in comparison to similar layers deposited by electron beam evaporation. We also used the laser beam as a diagnostic tool to characterize optical thin films by absorption and laser damage resistance. We investigated the increase in resistance to laser damage of optical layers by laser irradiation of the substrates under vacuum immediately before the coating process. Moreover, we investigated the optical properties of oxide films after uv-laser irradiation delivered from a KrF excimer laser.

Semiconductor quantum dots of cadmium sulfide, CdS, are approximately the size of proteins and are photoluminescent in the red, yellow, or green, depending on surface preparation. This photoluminescence is very sensitive to the Nature and amount of adsorbates. We have found that DNAs with intrinsic curvature adsorb more strongly to the surface of 47 Å CdS quantum dots, as judged by concentration-dependent changes in photoluminescence. The binding constants we obtain are similar to those found for nonspecific protein-DNA interactions. The surface groups of the CdS substrate also influence DNA adsorption. Thus these protein-sized colloidal particles can be used in chemical sensing applications for curved or kinked DNA; DNA with unusual structures is thought to influence biological function such as transcription.

Eine wesentliche Voraussetzung fur die Erhohung der Zuverlassigkeit von Hochleistungslaseranlagen ist eine Verbesserung der Laserfestigkeit der verwendeten optischen Bauelemente. Entsprechende Untersuchungen erfolgten mit Hilfe eines Nd:YAG-Lasers (Impulsdauer 85 ns, Wellenlange 1,06 μm) an Einzelschichten bzw. an den aus ihnen gebildeten Bauelementen, wobei der Strahldurchmesser auf der Probe 15 um betrug.

We describe the first example of immunoanalysis performed within an ionic liquid with minimal deleterious effect; our results bode well for the development of second-generation biosensors, particularly in applications involving poorly water soluble analytes including pesticides, phospholipids, and illicit drugs.

Conventionally cleaned fused silica substrates were irradiated immediately before the coating process with a CO2 laser. We then used electron beam technology to produce SiO, SiO2, ZrO2 and Ta2O5 single-layer and multilayer films. The damage threshold was determined with an Nd:YAG laser (λ=1.06 μm). We observed an increase in the laser damage threshold by a factor of up to 10.

An investigation was made of the influence of various technological factors governing the deposition and structure of optical coatings, made of refractory oxides and SiO2, on the damage threshold of single-layer multilayer systems. It was found that under optimal deposition conditions it was possible to prepare coatings (both highly reflecting and transmitting) with a damage threshold comparable with the threshold of the surface of glass exposed to neodymium laser radiation pulses of 2–85 ns duration.

We introduce time-resolved infrared spectroscopy as a powerful method to study the kinetics of RNA folding and unfolding transitions. A laser-induced temperature jump is used to initiate a perturbation in the RNA structure. A probe laser, tuned to a specific infrared absorption of the RNA, is then used to monitor the subsequent relaxation kinetics. A 10-ns pump pulse permits the investigation of fast, nanosecond events. In this work we probe two vibrational transitions, one at 1620cm−1 and one at 1661cm−1. The former transition reports mainly on the dynamics of A and U interactions, the latter is attributed to mainly G and C interactions. Our results reveal three distinct kinetic phases for each vibrational transition probed. We propose two models to describe the data. In one mechanism, the unfolded state partitions into two separate populations; each is conformationally biased to proceed via one of two distinct pathways. In an alternative model, folding proceeds through a series of sequentially populated intermediates. In both cases, the first step in the proposed folding mechanism is rate limiting (hundreds of microseconds) and involves a collapse into incorrectly folded intermediate populations. Two faster kinetic phases (tens of microseconds and hundreds of nanoseconds) follow in which the intermediate populations undergo localized reorganizational motions in the search for native contacts.

A 200W c.w. CO2 laser has been used to evaporate thin multilayer films of HfO2-SiO2 and ZrO2-SiO2. Higher values of laser damage resistance were found compared to similar layers produced by electron-beam evaporation.

LASER- ASSISTED DEPOSITION OF THIN FILMS FOR OPTICAL APPLICATIONSD. SCHAFER and B. BRAUNSAkademie der Wissenschaften der DDR, Zentralinstitut fur Optik und Spektroskopie1199 Berlin, DDRR. WOLF and B. STEIGER and G. ZSCHERPEIngenieurhochschule MittweidaPlatz der DSF, 9250 Mittweida, DDRABSTRACTA 200 W cw CO z laser was used to evaporate high refractory oxides, for laser substrateirradiation before the deposition and for modification of the electron beam depositionprocess. For the laser- assisted thin film deposition processes higher values of laserdamage resistance and a correlation between laser damage resistance and absorption were