Preserving morphology while extracting DNA: a non-destructive field-to-museum protocol for slide-mounted specimens.

Our study aimed to develop an optimised laboratory protocol ensuring the preservation of morphological structures and extraction of high-quality DNA sequences from Psychodidae (Insecta, Diptera) specimens. With 310 analysed specimens, we investigated the impact of distinct laboratory treatments by employing two shaking categories (constant and interrupted) with five different incubation periods (16, 12, 8, 4 and 2 hours) during the DNA extraction process. Notably, 80.65% of the specimens exhibited morphological changes during DNA extraction. Our results indicated no statistical difference between constant and interrupted shaking for the total of morphological structures lost. However, within each shaking category, the loss of structures was influenced significantly by the incubation period. Prolonged incubation correlated with increased structural losses, whereas shorter incubation periods caused minor alterations in structures lost. In addition, our results showed a significant difference between constant and interrupted shaking treatments for DNA concentration. Likewise, the incubation period showed differences within each shaking category. Successful COI sequencing was achieved in 89.6% of specimens, with negligible differences in DNA fragment lengths across treatments. Our findings underscore the importance of an optimised protocol and its potential in systematic research involving nematoceran dipteran specimens by balancing morphological integrity and DNA extraction efficiency.

Another crack in the Dark Taxa wall: a custom DNA barcoding protocol for the species-rich and common Eurytomidae (Hymenoptera, Chalcidoidea).

DNA barcodes are a great tool for accelerated species identification and for complementing species delimitation. Furthermore, DNA barcode reference libraries are the decisive backbone feature for any metabarcoding study in biodiversity monitoring, conservation or ecology. However, in some taxa, DNA barcodes cannot be generated with published primers at a satisfying success rate and these groups will consequently be largely missing from any barcoding-based species list. Here, we provide a custom DNA barcoding forward primer for the Eurytomidae (Hymenoptera, Chalcidoidea), elevating the success rate of high-quality DNA barcodes from 33% to 88%. Eurytomidae is a severely understudied, taxonomically challenging, species-rich group of primarily parasitoid wasps. High species numbers, diverse ecological roles and widespread and common presence identify Eurytomidae as one of many crucial families in terrestrial ecosystems. It is now possible to include Eurytomidae when studying and monitoring the terrestrial fauna, highlighting that barcoding-based approaches will need to routinely use different primers to avoid biases in their data and inferences. The new DNA barcoding protocol is also a prerequisite for our integrative taxonomy study of the group, aiming at delimiting and characterising Central European species and filling the GBOL (German Barcode Of Life) DNA barcode reference library with species-named and voucher-linked sequences.

Tilted 3D visual scenes influence lateropulsion: A single case study of pusher syndrome.

INTRODUCTION: Hemiparetic stroke patients with so-called "pusher syndrome" (synonyms: contraversive lateropulsion, contraversive pushing) use their non-paretic extremities to push toward their paralyzed side and actively resist external posture correction. The disorder is associated with a distorted perception of postural vertical combined with a maintained, or little deviating perception of visual upright. With the aim of reducing this mismatch, and thus reducing contraversive lateropulsion, we manipulated the orientation of visual input in a virtual reality setup. METHOD: We presented healthy subjects and an acute stroke patient with severe pusher syndrome a 3D visual scene that was either upright or tilted in roll plane by 20°. By moving the sitting participants in roll plane to the left and right, we assessed the occurrence of contraversive lateropulsion, namely the active resistance to external posture manipulation. RESULTS: With the 3D visual scene oriented upright, the patient with pusher syndrome showed the typical active resistance against tilts toward the ipsilesional side. He used his non-paretic arm to block the examiner's attempt to move the body axis toward that side. With the visual scene tilted to the ipsiversive left, his pathological resistance was significantly reduced. Statistically, the tolerated body tilt angles no longer differed from those of healthy subjects. CONCLUSIONS: We conclude that even short presentations of tilted 3D visual input can reduce symptoms of severe contraversive lateropulsion. The technique provides potential for a new treatment method of pusher syndrome and offers a simple, straightforward approach that can be effortlessly integrated in clinical practice. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00026700).

Digital Gait Biomarkers Allow to Capture 1-Year Longitudinal Change in Spinocerebellar Ataxia Type 3.

Measures of step variability and body sway during gait have shown to correlate with clinical ataxia severity in several cross-sectional studies. However, to serve as a valid progression biomarker, these gait measures have to prove their sensitivity to robustly capture longitudinal change, ideally within short time frames (eg, 1 year). We present the first multicenter longitudinal gait analysis study in spinocerebellar ataxias. We performed a combined cross-sectional (n = 28) and longitudinal (1-year interval, n = 17) analysis in Spinocerebellar Ataxia type 3 subjects (including seven preataxic mutation carriers). Longitudinal analysis showed significant change in gait measures between baseline and 1-year follow-up, with high effect sizes (stride length variability: P = 0.01, effect size rprb  = 0.66; lateral sway: P = 0.007, rprb  = 0.73). Sample size estimation for lateral sway indicates a required cohort size of n = 43 for detecting a 50% reduction of natural progression, compared with n = 240 for the clinical ataxia score Scale for the Assessment and Rating of Ataxia (SARA). These measures thus present promising motor biomarkers for upcoming interventional studies. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Photo-Thermoelectric Conversion Using Black Silicon with Enhanced Light Trapping Performance far beyond the Band Edge Absorption.

During the past years, much research work has been focused on efficiently harvesting solar energy with black silicon (b-Si). However, semiconductor Si can only utilize solar energy with wavelength smaller than λ = 1110 nm (bandgap Eg = 1.12 eV) for photovoltaic applications or photoelectrochemical conversions. Light with wavelength beyond the band edge (above λ = 1110 nm) cannot be used. Here, we prepared highly conductive b-Si without an apparent optical bandgap by a reactive ion etching process, which can largely absorb light with a wide range wavelength and even far into the near-infrared region (∼2500 nm). The optimized b-Si with surface texture shows the specular reflection rate lower than 0.1% and the average total reflection (specular reflectance + diffuse reflectance) is about 1.1%. Additionally, we briefly introduce the mechanism and reflection principle of surface nanostructured b-Si. By using b-Si structured material, we successfully convert the solar energy to electric power via photo-thermoelectric conversion, especially solar energy exceeding 1110 nm wavelength can also be efficiently used. The excellent light trapping of sunlight shows great potential for photothermal applications, such as photothermal imaging, seawater desalination, and further applications.

Population size estimates based on the frequency of genetically assigned parent-offspring pairs within a subsample.

Estimating population density as precise as possible is a key premise for managing wild animal species. This can be a challenging task if the species in question is elusive or, due to high quantities, hard to count. We present a new, mathematically derived estimator for population size, where the estimation is based solely on the frequency of genetically assigned parent-offspring pairs within a subsample of an ungulate population. By use of molecular markers like microsatellites, the number of these parent-offspring pairs can be determined. The study's aim was to clarify whether a classical capture-mark-recapture (CMR) method can be adapted or extended by this genetic element to a genetic-based capture-mark-recapture (g-CMR). We numerically validate the presented estimator (and corresponding variance estimates) and provide the R-code for the computation of estimates of population size including confidence intervals. The presented method provides a new framework to precisely estimate population size based on the genetic analysis of a one-time subsample. This is especially of value where traditional CMR methods or other DNA-based (fecal or hair) capture-recapture methods fail or are too difficult to apply. The DNA source used is basically irrelevant, but in the present case the sampling of an annual hunting bag is to serve as data basis. In addition to the high quality of muscle tissue samples, hunting bags provide additional and essential information for wildlife management practices, such as age, weight, or sex. In cases where a g-CMR method is ecologically and hunting-wise appropriate, it enables a wide applicability, also through its species-independent use.

Validation of enhanced kinect sensor based motion capturing for gait assessment.

Optical motion capturing systems are expensive and require substantial dedicated space to be set up. On the other hand, they provide unsurpassed accuracy and reliability. In many situations however flexibility is required and the motion capturing system can only temporarily be placed. The Microsoft Kinect v2 sensor is comparatively cheap and with respect to gait analysis promising results have been published. We here present a motion capturing system that is easy to set up, flexible with respect to the sensor locations and delivers high accuracy in gait parameters comparable to a gold standard motion capturing system (VICON). Further, we demonstrate that sensor setups which track the person only from one-side are less accurate and should be replaced by two-sided setups. With respect to commonly analyzed gait parameters, especially step width, our system shows higher agreement with the VICON system than previous reports.