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Item does not contain fulltext, INTRODUCTION: Neuroimmunological diseases such as autoimmune encephalitis (AE) or acquired demyelinating syndromes (ADS), can present with neurological symptoms and imaging features that are indistinguishable from mitochondrial diseases (MD) in particular at initial presentation. METHODS: Retrospective analysis of the clinical, laboratory and neuroimaging features of five patients who presented with signs of a neuroimmunological disease but all had pathological pathogenic variants in genes related to mitochondrial energy metabolism. RESULTS: Four patients presented with an acute neurological episode reminiscent of a possible AE and one patient with a suspected ADS at initial presentation. MRI findings were compatible with neuroimmunological diseases in all patients. In two children cerebrospinal fluid (CSF) studies revealed a mildly elevated cell count, two had elevated CSF lactate, none had oligoclonal bands (OCBs). All patients improved rapidly with intravenous steroids or immunoglobulins. Four patients had one or more relapses. Three patients showed worsening of their neurological symptoms with subsequent episodes and one patient died. Relapses in conjunction with new and progressive neurological symptoms, led to additional work-up which finally resulted in different genetic diagnosis of MD in all patients (MT-TL1, MT-ND5, APOA1-BP, HPDL, POLG). DISCUSSION: We would like to draw attention to a subset of patients with MD initially presenting with signs and symptoms mimicking neuroimmunological. Absence of CSF pleocytosis, elevated CSF lactate and progressive, relapsing course should trigger further (genetic) investigations in search of a MD even in patients with good response initially to immunomodulating therapies.

Nowadays, utilizing shallow geothermal energy for heating and cooling buildings has received increased interest in the building sector. Among different technologies, large borehole heat exchanger arrays are widely employed to supply heat to various types of buildings. Recently, a 16-borehole array was constructed to extract shallow geothermal energy to provide heat to a newly-developed public building in Berlin. To guarantee the quality of the numerical model and reveal its sensitivity to different subsurface conditions, model simulations were conducted for 25 years with two finite element simulators, namely the open-source code OpenGeoSys and the widely applied commercial software FEFLOW. Given proper numerical settings, the simulation results from OpenGeoSys and FEFLOW are in good agreement. However, further analysis reveals differences with respect to borehole inflow temperature calculation implemented in the two software. It is found that FEFLOW intrinsically uses the outflow temperature from the previous time step to determine the current inflow temperature, which makes it capable of much faster simulation by avoiding iterations within a single time step. In comparison, OpenGeoSys always updates the inflow and outflow temperature based on their current time step values. Because the updates are performed after each iteration, it delivers more accurate results with the expense of longer simulation time. Based on this case study, OpenGeoSys is a valid alternative to FEFLOW for modeling ground source heat pump systems. For modellers working in this field, it is thus recommended to adopt small enough time step size, so that potential numerical error can be avoided.

The use of phosphonates as antiscalants in membrane processes is common. Before they are discharged into the receiving water, they should be removed from the membrane concentrate to protect the aquatic environment. This study conducted fixed-bed column experiments on the adsorption of diethylenetriaminepenta(methylene phosphonic acid) (DTPMP) and ortho-phosphate on granular ferric (hydr)oxide (GFH). The objective was to investigate the adsorption and desorption performance using real membrane concentrate, while testing both the usability of the GFH and that of the regeneration solutions over multiple cycles. Whereas a synthetic solution with DTPMP allowed almost complete regeneration, the adsorption performance with real membrane concentrate at the original pH 8 decreased significantly. This could be attributed to the precipitation of calcium compounds which disturbed the adsorption/desorption process. With the introduction of a novel acidic regeneration step to remove the precipitates, an adsorption performance of 95% over 20 cycles was achieved. The hydrochloric acid (HCl) can be reused when its pH is kept constant by a pH control. The sodium hydroxide solution (NaOH) for alkaline regeneration can be reused several times. However, the desorption performance decreased significantly when its electrical conductivity dropped below 90 mS/cm. Replacing the NaOH regularly can significantly improve the desorption performance.

The fast-neutron-induced fission cross section of ²⁴²Pu was measured at the neutron time-of-flight facility nELBE. A parallel-plate fission ionization chamber with novel, homogeneous, large-area ²⁴²Pu deposits on Si-wafer backings was used to determine this quantity relative to the IAEA neutron cross-section standard ²³²U(n, f ) in the energy range of 0.5 to 10 MeV. The number of target nuclei was determined from the measured spontaneous fission rate of ²⁴²Pu. This helps to reduce the influence of the fission fragment detection efficiency on the cross section. Neutron transport simulations performed with GEANT 4, MCNP 6, and FLUKA 2011 are used to correct the cross-section data for neutron scattering. In the reported energy range the systematic uncertainty is below 2.7% and on average the statistical uncertainty is 4.9%. The determined results show an agreement within 0.67(16)% to recently published data and a good accordance to current evaluated data sets.

Periphytic biofilms are the major resource for many herbivorous invertebrates in both marine and freshwater benthos. They are of crucial importance for benthic food webs, substrate stability, and biogeochemical processes in littoral zones. While the importance of invertebrate grazing on biofilms has been studied extensively using natural, mixed algal communities grown on artificial substrates, there is so far no method available to create defined periphyton communities for these grazing studies. The reason for this is that many benthic algae interact with co-occurring species within the extracellular polymeric substances (EPSs) that form the nonorganismic part of the biofilm. Here, we present a novel method that allows the manufacturing of defined monoculture and multispecies biofilms by using an alginate polymer as artificial EPS structure, into which algal cultures can be embedded. Using confocal laser scanning microscopy, we show that alginate effectively embeds various algal taxa in an EPS matrix that is very similar to natural biofilms. In a grazing experiment, we demonstrate that several common freshwater herbivorous invertebrates can graze these alginate biofilms efficiently. As the method is easy to handle, it allows for highly controlled feeding experiments with benthic herbivores to assess, for example, the role of algal biodiversity on the efficiency of top-down control, the effects of environmental drivers such as nutrients, salinity, or seawater acidification on biofilm community structure, and the impacts of herbivory in benthic communities.

Assessing the conservation status of a species is strongly dependent upon data on species distribution and abundance. With the emergence of novel methods for species monitoring – such as the use of environmental DNA (eDNA) – monitoring success can be improved at reduced expenditure in the field, particularly in remote regions and terrains where access is difficult or dangerous.The highly endangered crocodile lizard (Shinisaurus crocodilurus Ahl, 1930) inhabits fragmented sites of the remaining evergreen forest with running water systems in a narrow distribution range in southern China and north‐east Vietnam. Crocodile lizards spend most of the day within or above water bodies, which are commonly remote and inaccessible. To monitor recent spatial occurrences, and to confirm the persistence or extinction of previously reported populations (especially in heavily altered habitats), the suitability of using eDNA and quantitative polymerase chain reaction (qPCR) was tested as an alternative method for monitoring this semiaquatic lizard.To assess the accuracy and limitations of this method, eDNA results from the field were compared with eDNA data from mesocosms and census data on the actual abundance of this species in the field.Environmental DNA of the crocodile lizard was detected in all of the positive controls, and in four of six natural sites; thus, all data collected using traditional field surveys were confirmed with eDNA results.eDNA monitoring was found to be a reliable method for assessing the viability of populations; we suggest that it should be developed as a tool for efficient wildlife management, particularly under difficult field and funding conditions.

Unidirectional drift is amongst the most relevant population regulators in riverine animal populations. Drift occurs randomly, but it can also be a behavioural response to abiotic and biotic stressors, or the result of catastrophic events such as heavy rain. In this study, we investigate the spatiotemporal distribution of larvae of the fire salamander (Salamandra salamandra) in three headwater streams in the Eifel mountains, Western Germany. We marked 568 salamander larvae to conduct capture-recapture estimates of abundance, and followed their individual fate throughout the season. Population density of larval salamanders along the stream showed both strong temporal and spatial variation. Random drift of salamander larvae was particularly rare, and drift did not result in a size structuring of larval populations in the field. Yet, catastrophic events of high summer precipitation were the best predictor for pulse-wise restructuring of the salamander larvae's density distribution. Strong discharge coincided with a severe decrease in population density, and thus appears to be the most relevant cause of mortality for salamander larvae. Furthermore, we find strong indications that drift has the potential to influence this species' evolutionary processes, as well as its ecological prevalence.

Neutron total cross sections of natFe, 197Au and natW have been measured at the nELBE neutron time-of-flight facility in the energy range from 0.2 - 8 MeV with an uncertainty due to counting statistics of up to 2 % and a total uncertainty due to systematic effects of 1 %. The neutrons are produced with the superconducting electron accelerator ELBE using a liquid lead circuit as photo-neutron target. By periodical sample-in-sample-out measurements the transmission of the sample materials has been determined using a low-threshold plastic scintillation detector. The resulting effective total cross sections show good agreement with previously measured data that cover only part of the energy range available at nELBE. The results have also been compared to evaluated library files and recent calculations based on a dispersive coupled channel optical model potential.