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Radial Jet Drilling (RJD) is a stimulation technique to increase a well’s performance through creation of multiple laterals of up to 100 m long. The technique has been used in the petroleum industry for several years and recently also for geothermal reservoirs. Interpretation of well tests of a well with multiple laterals may become problematic if the effect of the laterals is not correctly modelled. In this work it is investigated what the impact of RJD laterals is on the pressure transients for both single and dual porosity reservoirs. A semi-analytic model for the calculation of the transient well pressure that accounts explicitly for the RJD well geometry is developed and validated with a detailed numerical simulation. The results show that changes in the lateral configuration affect the pressure transients significantly. In particular for single porosity media, the laterals affect the pressure transients in ways that cannot be captured by representing the stimulation by a skin factor. Since the RJD process is unsteered and the exact configuration of the laterals uncertain, the model may potentially assist in estimating the effectiveness of the stimulation such as the achieved reach of the laterals. Although the work was carried out in the context of RJD application in geothermal reservoirs, the presented model approach can be extended to multi-lateral wells in oil or gas reservoirs.

This paper presents a study into the possibility to enhance dissolution of CO2 in brine using nanoparticles (NPs) as a remediation and/or mitigation option for unwanted migration of CO2. The idea is to inject a homogeneous mixture of NPs and CO2 into the stored CO2. The heavier NP-CO2 mixture spreads on the interface between the CO2 and brine. The heavier NPs move into the brine together with the CO2 and increase the density of the brine. This will enhance the process of convective mixing which increases the dissolution rate of CO2. However, it was found that the method is inefficient in terms of the amount of NPs needed compared to the increase in CO2 dissolution. For example, to achieve an increase of 50% in the CO2 dissolution rate, 1 kg of NP is needed to dissolve 3 kg extra CO2 for an example case at 1 km depth. This makes the method unattractive both technically and economically: a large effort is required for engineering NPs with the correct properties, the risks associated are clogging and pressure increase, and the method is expensive.

is a refereed international journal that publishes original articles on all aspects of specialized communication and provides an interdisciplinary forum for researchers and teachers interested in this field. FACHSPRACHE is committed to promoting high-quality research and to improving specialized communication and knowledge transfer including the qualifications required for this. The journal places equal emphasis on rigour and comprehensibility in an attempt to bridge the gap between researchers who may come from different disciplines but who share a common interest in specialized communication. These disciplines may range from linguistics, psychology, lexicography, terminology, and translation studies to the neurosciences as well as domains such as business administration, economics, law, medicine, science and engineering. Special issues focusing on particular individual areas are published regularly.

An observation of the 1S-3S and 1S-3D two-photon transitions in an atomic hydrogen beam using direct frequency-comb spectroscopy in a Doppler-free arrangement is reported. The measurements of these transition frequencies may be used for an improved determination of the Rydberg constant and the 1S Lamb shift and could shed light on the current discrepancy in the determination of the proton charge radius. Concurrently, a frequency comb well-suited for high-precision, Doppler-free spectroscopy in the deep ultraviolet (DUV) wavelength region is demonstrated.

We identify a systematic present in two-photon direct frequency comb spectroscopy (DFCS) which is a result of chirped laser pulses and is amanifestation of the first-order Doppler effect. We carefully analyze this systematic and propose methods for its mitigation within the context of our measurement of the hydrogen 1S-3S transition. We also report on our determination of the absolute frequency of this transition, which is comparable to a previous measurement using continuous-wave spectroscopy [O. Arnoult et al., Eur. Phys. J. D 60, 243 (2010)], but was obtained with a different experimental method.

The addition of immunocytochemical staining procedures to a diagnostic cytology service enables greater specificity of interpretation for many common disease conditions, especially neoplastic diseases. However, well-tested immunohistochemical techniques may require modification for cytologic specimens, and other considerations are necessary when working with air-dried cells. In this article, we describe our experience in evaluating options for sample transport and handling, and discuss methods for obtaining control cells from a variety of tissues for use in immunocytochemical staining. Important immunocytochemical principles and techniques, including fixation, antigen retrieval, and use of primary and secondary antibodies in manual and automated staining systems are described as used in our laboratory for cytologic specimens. Although we emphasize methods relevant to diagnostic laboratories receiving samples from external clients, the information is also applicable to any laboratory interested in adding or enhancing immunocytochemical services.

As an attempt to help conserve the endangered European mink Mustela lutreola (Linnaeus, 1761), a reintroduction program was started in a nature reserve in Saarland, Germany; the present study is part of this ongoing reintroduction project. Within the first 2 yr period, 48 (16 m, 32 f) founder animals were reintroduced, out of a total of about 75 animals intended for release in the course of the 3 yr project. Prior to reintroduction, the animals were acclimatized using soft-release pens where they were preconditioned with natural prey . A number of individuals (n = 18) were set free in groups of mating partners (ffm, fm) and in mother-offspring groups. Thirty-three European mink (14 m, 19 f) were fitted with intraperitonial transmitters and radio-tracked and surveyed via live-trapping. Animals were monitored from April 2006 to May 2008 to determine the distribution, size and temporal changes in home range. Released animals showed linear home ranges spreading along rivers and brooks. Home range sizes were 7.2 km (88 ha) for 1 adult male, 0.2-5.9 km (1-505 ha) for adult females, around 1.7-5.6 km (17-132 ha) for juvenile males and 9.2 km (778 ha) for 1 juvenile female, respectively. The released adults showed inter-, but only few intra-, sexual home range overlaps. In contrast, juveniles did not show any home range overlaps. In winter, home range size decreased to a minimum of about 1 km. Further, home range size for females decreased around parturition but increased successively at time of weaning. The activity pattern of released animals was highest at night (especially around dusk and dawn).

Background Although this effect is well known, tailored treatment methods have not yet been broadly adopted. The aim of this study was to identify those patient characteristics that most influence the impairment of quality of life and thus to identify those patients who need and can benefit most from specific intervention treatment. Methods 1879 cancer patients were given the EORTC QLQ C-30 questionnaire at the beginning and end of their inpatient rehabilitation. Patients’ scores were compared to those of 2081 healthy adults (Schwarz and Hinz, Eur J Cancer 37:1345–1351, 2001). Furthermore, differences in quality of life corresponding to sex, age, tumor site, TNM stage, interval between diagnosis and rehabilitation, and therapy method were examined. Results Compared to the healthy population, the study group showed a decreased quality of life in all analyzed domains. This difference diminished with increasing age. Women reported a lower quality of life then men in general. Patients with prostate cancer showed the least impairment in several domains. Patients having undergone chemotherapy as well as radiotherapy were impaired the most. Surprisingly, TNM stage and interval between diagnosis and rehabilitation did not significantly influence quality of life. Global quality of life and all functional domains significantly improved after a 3-week rehabilitation program. Conclusions Despite an individualized and increasingly better tolerable therapy, the quality of life of cancer patients is still considerably impaired. However, systematic screening of psychosocial aspects of cancer, e.g. quality of life, could enable improved intervention. peerReviewed

Quantum interference arising from spontaneous emission, or cross-damping, is an important yet frequently overlooked systematic in precision spectroscopy experiments which aim to determine a transition frequency with an uncertainty smaller than the natural linewidth. Here, we calculate the effects of such interference in two-photon frequency-comb spectroscopy using a perturbative approach and by integration of the density matrix equations. We then apply these techniques to the two-photon spectroscopy of the hydrogen $1S\ensuremath{-}3S$ transition currently being performed in our group. Depending on the detection geometry, we find distortions of the line shapes which can lead to systematic errors of $\ensuremath{\sim}$1 kHz if such interference effects are ignored in the data analysis. This result is independent of whether a cw laser or frequency comb is used for the excitation. Finally, we propose a time-dependent detection scheme which, when used in conjunction with frequency-comb excitation, can mitigate the line distortions arising from such interference.

International audience; Precise determinations of transition frequencies of simple atomic systems are required for a number of fundamental applications such as tests of quantum electrodynamics (QED), the determination of fundamental constants and nuclear charge radii. The sharpest transition in atomic hydrogen occurs between the metastable 2S state and the 1S ground state. Its transition frequency has now been measured with almost 15 digits accuracy using an optical frequency comb and a cesium atomic clock as a reference [1]. A recent measurement of the 2S - 2P3/2 transition frequency in muonic hydrogen is in significant contradiction to the hydrogen data if QED calculations are assumed to be correct [2, 3]. We hope to contribute to this so-called "proton size puzzle" by providing additional experimental input from hydrogen spectroscopy.

Thanks to the high peak intensities of ultrashort pulse trains that make up an optical frequency comb, conversion to much shorter wavelengths is readily available. Therefore direct frequency comb spectroscopy may offer the possibility of extending high-resolution spectroscopy to spectral regions that are unexplored so far. In this work, we investigate the impact of a chirp, i.e., a varying frequency across the pulses, on the excitation rate obtainable with two-photon direct frequency comb spectroscopy. Using the cesium $6 {}^{2}{S}_{1/2}$-$8 {}^{2}{S}_{1/2}$ two-photon transition at $822$ nm, we show that destructive interference of various quantum paths reduces the excitation rate with the inverse of the time bandwidth product of the exciting pulses.

The clock-regulated RNA recognition motif (RRM)-containing protein AtGRP7 (Arabidopsis thaliana glycine-rich RNA-binding protein) influences the amplitude of its transcript oscillation at the post-transcriptional level. This autoregulation relies on AtGRP7 binding to its own pre-mRNA. The sequence and structural requirements for this interaction are unknown at present. In this work, we used photoinduced electron transfer fluorescence correlation spectroscopy (PET-FCS) as a novel technique to study the role of target RNA secondary structure and conformational dynamics during the recognition and binding process. Conformational dynamics of single-stranded (ss) oligonucleotides were studied in aqueous solution with single-molecule sensitivity and high temporal resolution by monitoring fluorescence quenching of the oxazine fluorophore MR121 by guanosine residues. Comparative analysis of translational diffusion constants revealed that both ssRNA and ssDNA bind to AtGRP7 with similar dissociation constants on the order of 10(-7) M and that a minimal binding sequence 5'-UUC UGG-3' is needed for recognition by AtGRP7. PET-FCS experiments demonstrated that conformational flexibility of short, single-stranded, MR121-labeled oligonucleotides is reduced upon AtGRP7 binding. In contrast to many other RRM proteins, AtGRP7 binds to ssRNA preferentially if the RNA is fully stretched and not embedded within a stable secondary structure. The results suggest that AtGRP7 binding leads to a conformational rearrangement in the mRNA, arresting the flexible target sequence in an extended structure of reduced flexibility that may have consequences for further post-transcriptional processing of the mRNA.

Recharge has been simulated in two European basins: upper Guadiana (Spain) and Noor (Netherlands)

Increasingly computer assisted techniques are used for history matching reservoir models. Such methods will become indispensable in view of the increasing amount of information generated by intelligent wells, in which case manual interpretation becomes too time consuming. Also, with the increasing possibilities for controlling a reservoir, a better prediction of the reservoir behavior is very important. A technique that has received considerable attention lately is the Ensemble Kalman Filter (EnKF), which is a sequential updating technique based on the Bayesian notion of updating prior information with observations (measurements). The EnKF has already been proven to be useful for history matching of real fields. Some of the advantages of the EnKF are its sequential nature, the large number of parameters that can be estimated (10000+) and the fact that an uncertainty estimate is generated. The most important and time consuming step for anyone wanting to do a history match with the EnKF is creating the initial ensemble including defining all the proper initial uncertainties. This paper presents an integrated workflow for creating an initial ensemble for a channelized reservoir and updating the ensemble sequentially using the EnKF. The resulting ensemble of history matched models is then used to predict the expected production and associated uncertainty for a new production strategy. The quality of the prediction is compared to the predictions from a model which was history matched manually. The improved predictive capabilities of the models which were history matched with the EnKF allows for better optimization of the production strategy for the complex channel geometry. Moreover, the updated uncertainty estimate shows the risks involved with some of the newly proposed wells, which allows for better decision making.

Within the research framework of the "Integrated System Approach Petroleum Production" (ISAPP) knowledge center of TNO, TU Delft and Shell, the necessity of taking the interaction between dynamic reservoir and dynamic well behavior into account when optimizing a producing asset is investigated. To simulate dynamic phenomena in the well and in the reservoir, a dynamic multiphase well simulation tool (OLGA) and a dynamic multiphase reservoir simulator (MoReS) have been used. Both simulators have been coupled using an explicit scheme. The dynamic well simulator, the dynamic reservoir simulator and the coupled dynamic well-reservoir simulator have been used to simulate a realistic test case which consists of a horizontal well with three inflow sections located in a thin oil rim. A number of scenarios are investigated that play a crucial role during different stages of the well's lifetime: naturally occurring phenomena, e.g. coning, and production dynamics, e.g. shut-in. The results of dynamic well simulations, dynamic reservoir simulations and coupled well-reservoir simulations are presented and an overview is given of the cases where the results of the coupled simulations are significantly more accurate in comparison to stand-alone well or reservoir simulations. For gas coning it is shown that the coupled simulator has much faster pressure transients after gas breakthrough than the dynamic reservoir simulator. Therefore, the coupled well-reservoir simulator should be used to simulate gas breakthrough and to optimize production using gas coning control. For small time scale phenomena, order of less then one day, the well and reservoir transients overlap. Simulations show that the coupled simulator is essential for an accurate prediction of the well-reservoir interaction during these small time scale phenomena.

Within the EC funded Horizon 2020 project SURE (Novel Productivity Enhancement Concept for a Sustainable Utilization of a Geothermal Resource) the radial jet drilling (RJD) technology is investigated and tested as a method to increase performance of insufficiently performing geothermal wells. Radial jet drilling uses the power of a focused jet of fluids, applied to a rock through a coil inserted in an existing well. This technology is likely to provide much better control of the enhanced flow paths around a geothermal well and does not involve the amount of fluid as conventional hydraulic fracturing, thereby reducing the risk of induced seismicity considerably. RJD shall be applied to access and connect high permeable zones within geothermal reservoirs to the main well with a higher degree of control compared to conventional stimulation technologies. We investigated the technology over various spatial and temporal scales ranging from short term laboratory experiments to field scale applications. Here we give an overview about our work.