Upper limb movement quality measures: comparing IMUs and optical motion capture in stroke patients performing a drinking task.

Introduction: Clinical assessment of upper limb sensorimotor function post-stroke is often constrained by low sensitivity and limited information on movement quality. To address this gap, recent studies proposed a standardized instrumented drinking task, as a representative daily activity combining different components of functional arm use. Although kinematic movement quality measures for this task are well-established, and optical motion capture (OMC) has proven effective in their measurement, its clinical application remains limited. Inertial Measurement Units (IMUs) emerge as a promising low-cost and user-friendly alternative, yet their validity and clinical relevance compared to the gold standard OMC need investigation. Method: In this study, we conducted a measurement system comparison between IMUs and OMC, analyzing 15 established movement quality measures in 15 mild and moderate stroke patients performing the drinking task, using five IMUs placed on each wrist, upper arm, and trunk. Results: Our findings revealed strong agreement between the systems, with 12 out of 15 measures demonstrating clinical applicability, evidenced by Limits of Agreement (LoA) below the Minimum Clinically Important Differences (MCID) for each measure. Discussion: These results are promising, suggesting the clinical applicability of IMUs in quantifying movement quality for mildly and moderately impaired stroke patients performing the drinking task.

Consistency between Treatment Effects on Clinical and Brain Atrophy Outcomes in Alzheimer's Disease Trials.

BACKGROUND: Longitudinal changes in volumetric MRI outcome measures have been shown to correlate well with longitudinal changes in clinical instruments and have been widely used as biomarker outcomes in clinical trials for Alzheimer's disease (AD). While instances of discordant findings have been noted in some trials, especially the recent amyloid-removing therapies, the overall relationship between treatment effects on brain atrophy and clinical outcomes, and how it might depend on treatment target or mechanism, clinical instrument or imaging variable is not yet clear. OBJECTIVE: To systematically assess the consistency and therapeutic class-dependence of treatment effects on clinical outcomes and on brain atrophy in published reports of clinical trials conducted in mild cognitive impairment (MCI) and/or AD. DESIGN: Quantitative review of the published literature. The consistency of treatment effects on clinical and brain atrophy outcomes was assessed in terms of statistical agreement with hypothesized equal magnitude effects (e.g., 30% slowing of both) and nominal directional concordance, as a function of therapeutic class. SETTING: Interventional randomized clinical trials. PARTICIPANTS: MCI or AD trial participants. INTERVENTION: Treatments included were those that involved ingestion or injection of a putatively active substance into the body, encompassing both pharmacological and controlled dietary interventions. MEASUREMENTS: Each trial included in the analysis reported at least one of the required clinical outcomes (ADAS-Cog, CDR-SB or MMSE) and at least one of the required imaging outcomes (whole brain, ventricular or hippocampal volume). RESULTS: Data from 35 trials, comprising 185 pairwise comparisons, were included. Overall, the 95% confidence bounds overlapped with the line of identity for 150/185 (81%) of the imaging-clinical variable pairs. The greatest proportion of outliers was found in trials of anti-amyloid antibodies that have been shown to dramatically reduce the level of PET-detectable amyloid plaques, for which only 13/33 (39%) of observations overlapped the identity line. A Deming regression calculated using all data points yielded a slope of 0.54, whereas if data points from the amyloid remover class were excluded, the Deming regression line had a slope of 0.92. Directional discordance of treatment effects was also most pronounced for the amyloid-removing class, and for comparisons involving ventricular volume. CONCLUSION: Our results provide a frame of reference for the interpretation of clinical and brain atrophy results from future clinical trials and highlight the importance of mechanism of action in the interpretation of imaging results.

Significant differences in functional outcome between upper and lower limbs after vascular trauma of the extremities.

BACKGROUND: This study aimed to compare the functional results between upper (UE) and lower extremity (LE) following arterial reconstruction due to vascular trauma. METHODS: Patients treated for arterial injuries with vascular reconstruction at two centres between 2005 and 2014 were assessed. The physical fitness questionnaire - Fitnessfragebogen (FFB-Mot) - was evaluated. The differences between pre- and post-traumatic values were compared statistically for UE and LE. Inability to return to the preoperative workplace or postoperative loss of at least 10% of the FFB-Mot were defined as the primary outcome events. RESULTS: Twenty-seven patients could be re-evaluated. The primary outcome event occurred in 52% (14/27) without significant difference between UE (43%) and LE (62%) (p = 0.45). The difference between the pre- and post-traumatic FFB-Mot scores showed a significantly poorer functional outcome after LE vascular injury (p = 0.012). CONCLUSION: Results indicate a poorer functional outcome after vascular extremity trauma to the LE than to the UE.

Plastics in the global environment assessed through material flow analysis, degradation and environmental transportation.

Knowledge on environmental plastic emission and spatial and temporal accumulation is vital for the development of successful mitigation strategies and risk assessments of plastics. In this study, emissions of both micro and macro plastic from the plastic value chain to the environment were assessed on a global level through a mass flow analysis (MFA). All countries, 10 sectors, 8 polymers and 7 environmental compartments (terrestrial, freshwater or oceanic) are distinguished in the model. The results assess a loss of 0.8 million tonnes (mt) of microplastics and 8.7 mt of macroplastics to the global environment in 2017. This is respectively 0.2 % and 2.1 % of plastics produced in the same year. The packaging sector contributed most for macroplastic emissions, and tyre wear for microplastic emissions. With the MFA results, accumulation, degradation and environmental transportation are considered in the Accumulation and dispersion model (ADM) until 2050. This model predicts macro- and microplastic accumulation in the environment to 2.2 gigatonnes (Gt) and 3.1 Gt in 2050 respectively (scenario: yearly consumption increase of 4 %). This will be 30 % less when a yearly production reduction of 1 % until 2050 is modeled to 1.5 and 2.3 Gt macro and microplastics respectively. Almost 2.15 Gt of micro and macroplastics accumulate in the environment until 2050 with zero plastic production after 2022 due to leakage from landfills and degradation processes. Results are compared to other modeling studies quantifying plastic emissions to the environment. The current study predicts lower emissions to ocean and higher emissions to surface waters like lakes and rivers. Non aquatic, terrestrial compartments are observed to accumulate most plastics emitted to the environment. The approach used results in a flexible and adaptable model that addresses plastic emissions to the environment over time and space, with detail on country level and environmental compartments.

Main radiation pathways in the landscape of Armenia.

PURPOSE: To investigate sources, accumulation, and vertical migration of radionuclides in Armenia, and their impact on biota. CONCLUSIONS: This review describes the radiation status in the landscape of Armenia and features of the impact of natural and human-generated radiation on human and non-human biotas, according to studies of Armenian scientists carried out since the middle of the last century. The mountain landscape demonstrates the diversity, speciation, and radioresistance of the biota, which arise under radiation exposure in a variable environment. Although the effects of radiation have been described for a long time, some of them require further study. It is important to present the data collected in order to produce a base line for future studies of radiation effects and interactions with other stressors caused by climate change.

In Vivo Detection of Changes Related to Cortical Columnar Organization and Neuroinflammation Across the AD Continuum.

BACKGROUND: Alzheimer's disease (AD) neuropathology reveals progressive microstructural alterations of cortical architecture. Recent studies reported intriguing biphasic trajectories of cortical structural changes in the early stages of Alzheimer's disease (AD), comprising decreased mean diffusivity (MD) and increased cortical thickness in cognitively normal amyloid-positive individuals, ahead of increases and decreases, respectively, in subsequent disease stages. OBJECTIVE: To better understand the cytoarchitectural correlates of these observations, we assessed novel cortical diffusion tensor imaging (DTI) metrics that are correlated with disruption of cortical minicolumns and protein deposition. DESIGN: Cross-sectional and longitudinal analysis of whole brain and temporal lobe cortical diffusivity measures. Investigation of associations between baseline cortical diffusivity values and 24-month longitudinal structural-MRI changes. Investigations of the relationships between cortical diffusivity measures and biomarkers of neuroinflammation. SETTING: Alzheimer's Disease Neuroimaging Initiative (ADNI). PARTICIPANTS: Twenty-four amyloid-negative controls (CN-), 28 amyloid-positive controls (CN+), 46 amyloid-positive subjects with mild cognitive impairment (MCI+) and 22 amyloid-positive subjects with AD were included. MEASUREMENTS: 3DT1 and DTI scans at baseline and approximately 24-month follow-up were used to calculate cortical MD and three novel cortical diffusivity measures: the angle between the radial minicolumnar axis and the principal diffusion direction (AngleR); the diffusion components perpendicular to the minicolumns (PerpPD+), and the principal diffusion component parallel with the minicolumns (ParlPD). Cortical macrostructural measurements (cortical volume fraction and cortical thickness), were used to test the hypothesis that baseline cortical diffusivity values can predict change in structural MRI outcomes over approximately 24 months. CSF soluble TREM2 and progranulin (PGRN) concentrations were used to investigate associations with microglial activity and potentially other aspects of neuroinflammation. RESULTS: Cortical diffusivity metrics revealed a dependence on disease stage, with AngleR and PerpPD+ displaying biphasic relationships and ParlPD a monotonic relationship with clinical severity. The novel metrics were able to differentiate between Amyloid+ and Amyloid- controls (AngleR) and to differentiate among disease stages along the AD continuum (PerpPD+). Linear regression revealed significant associations between baseline cortical diffusivity values and subsequent 24-month longitudinal structural-MRI changes. AngleR values were significantly associated with CSF sTREM2 and PGRN concentrations. CONCLUSIONS: Cortical diffusivity parameters reflecting minicolumnar organization and neuroinflammation may provide a sensitive and biologically interpretable measurement of cortex quality and microstructure across the AD continuum.

Characterization of atherosclerotic plaques in blood vessels with low oxygenated blood and blood pressure (Pulmonary trunk): role of growth differentiation factor-15 (GDF-15).

BACKGROUND: Growth differentiation factor (GDF)-15 is linked to inflammation, cancer, and atherosclerosis. GDF-15 is expressed in most tissues but is extremely induced under pathological conditions. Elevated serum levels are suggested as a risk factor and a marker for cardiovascular diseases. However, the cellular sources and the effects of GDF-15 on the cardiovascular system have not been completely elucidated including progression, and morphology of atherosclerotic plaques. Thus, this work aimed to characterize the influence of GDF-15 deficiency on the morphology of atherosclerotic plaques in blood vessels with low-oxygen blood and low blood pressure as the pulmonary trunk (PT), in hypercholesterolemic ApoE-/- mice. METHODS: GDF-15-/- ApoE-/- mice were generated by crossbreeding of ApoE-/-- and GDF-15-/- mice. After feeding a cholesterol-enriched diet (CED) for 20 weeks, samples of the brachiocephalic trunk (BT) and PT were dissected and lumen stenosis (LS) was measured. Furthermore, changes in the cellularity of the PT, amounts of apoptosis-, autophagy-, inflammation- and proliferation-relevant proteins were immunohisto-morphometrically analyzed. Additionally, we examined an atherosclerotic plaque in a human post mortem sample of the pulmonary artery. RESULTS: After CED the body weight of GDF-15-/-ApoE-/- was 22.9% higher than ApoE-/-. Double knockout mice showed also an 35.3% increase of plasma triglyceride levels, whereas plasma cholesterol was similar in both genotypes. LS in the BT and PT of GDF-15-/-ApoE-/- mice was significantly reduced by 19.0% and by 6.7% compared to ApoE-/-. Comparing LS in PT and BT of the same genotype revealed a significant 38.8% (ApoE-/-) or 26.4% (GDF-15-/-ApoE-/-) lower LS in the PT. Immunohistomorphometry of atherosclerotic lesions in PT of GDF-15-/-ApoE-/- revealed significantly increased levels (39.8% and 7.3%) of CD68 + macrophages (MΦ) and α-actin + smooth muscle cells than in ApoE-/-. The density of TUNEL + , apoptotic cells was significantly (32.9%) higher in plaques of PT of GDF-15-/-ApoE-/- than in ApoE-/-. Analysis of atherosclerotic lesion of a human pulmonary artery showed sm-α-actin, CD68+, TUNEL+, Ki67+, and APG5L/ATG+ cells as observed in PT. COX-2+ and IL-6+ immunoreactivities were predominantly located in endothelial cells and subendothelial space. In BT and PT of GDF15-/-ApoE-/- mice the necrotic area was 10% and 6.5% lower than in ApoE-/-. In BT and PT of GDF15-/-ApoE-/- we found 40% and 57% less unstable plaques than ApoE-/- mice. CONCLUSIONS: Atherosclerotic lesions occur in both, BT and PT, however, the size is smaller in PT, possibly due to the effect of the low-oxygen blood and/or lower blood pressure. GDF-15 is involved in atherosclerotic processes in BT and PT, although different mechanisms (e.g. apoptosis) in these two vessels seem to exist.

Differentiating migraine, cervicogenic headache and asymptomatic individuals based on physical examination findings: a systematic review and meta-analysis.

BACKGROUND: Migraine and cervicogenic headache (CGH) are common headache disorders, although the large overlap of symptoms between them makes differential diagnosis challenging. To strengthen differential diagnosis, physical testing has been used to examine for the presence of musculoskeletal impairments in both conditions. This review aimed to systematically evaluate differences in physical examination findings between people with migraine, CGH and asymptomatic individuals. METHODS: The databases MEDLINE, PubMed, CINAHL, Web of Science, Scopus, EMBASE were searched from inception until January 2020. Risk of bias was assessed with the Downs and Black Scale for non-randomized controlled trials, and with the Quality Assessment of Diagnostic Accuracy Studies tool for diagnostic accuracy studies. When possible, meta-analyses with random effect models was performed. RESULTS: From 19,682 articles, 62 studies were included in this review and 41 were included in the meta-analyses. The results revealed: a) decreased range of motion [°] (ROM) on the flexion-rotation test (FRT) (17.67, 95%CI:13.69,21.65) and reduced neck flexion strength [N] (23.81, 95%CI:8.78,38.85) in CGH compared to migraine; b) compared to controls, migraineurs exhibit reduced flexion ROM [°] (- 2.85, 95%CI:-5.12,-0.58), lateral flexion ROM [°] (- 2.17, 95% CI:-3.75,-0.59) and FRT [°] (- 8.96, 95%CI:-13.22,-4.69), reduced cervical lordosis angle [°] (- 0.89, 95%CI:-1.72,-0.07), reduced pressure pain thresholds over the cranio-cervical region [kg/cm2], reduced neck extension strength [N] (- 11.13, 95%CI:-16.66,-5.6) and increased activity [%] of the trapezius (6.18, 95%CI:2.65,9.71) and anterior scalene muscles (2.87, 95%CI:0.81,4.94) during performance of the cranio-cervical flexion test; c) compared to controls, CGH patients exhibit decreased neck flexion (- 33.70, 95%CI:-47.23,-20.16) and extension (- 55.78, 95%CI:-77.56,-34.00) strength [N]. CONCLUSION: The FRT and neck flexion strength could support the differential diagnosis of CGH from migraine. Several physical tests were found to differentiate both headache types from asymptomatic individuals. Nevertheless, additional high-quality studies are required to corroborate these findings. STUDY REGISTRATION: Following indications of Prisma-P guidelines, this protocol was registered in PROSPERO on 21/05/2019 with the number CRD42019135269 . All amendments performed during the review were registered in PROSPERO, indicating the date and what and why was changed.

Balloon valvuloplasty of valvular pulmonary stenosis in a neonatal foal.

In a 1-day old filly with a loud heart murmur, transthoracic echocardiography revealed right ventricular hypertrophy associated with severe pulmonary valvular stenosis and a transvalvular pressure gradient (between right ventricle and pulmonary artery) of 125 mmHg. Computed tomographic angiography confirmed the finding, with no evidence of other relevant concurrent abnormalities. Balloon valvuloplasty was performed using a single balloon technique. The foal recovered well from anaesthesia. Following the procedure, the right ventricle-pulmonary artery transvalvular gradient decreased to 38 mmHg. At follow up examinations after 1 month, 1 year and 2 years, the filly showed normal exercise capacity and echocardiography confirmed the persistent substantial improvement in the transvalvular outflow gradient.

Effectiveness of reverse total shoulder arthroplasty for primary and secondary fracture care: mid-term outcomes in a single-centre experience.

BACKGROUND: The introduction of reverse total shoulder arthroplasty (RSA) as a treatment option in complex proximal humeral fractures, has significantly extended the surgical armamentarium. The aim of this study was to investigate the mid-term outcome following fracture RSA in acute or sequelae, as well as salvage procedures. It was hypothesized that revision RSA (SRSA) leads to similar mid-term results as primary fracture treatment by RSA (PRSA). METHODS: This retrospective study describes the radiological and clinical mid-term outcomes in a standardized single-centre and Inlay design. Patients who underwent RSA in fracture care between 2008 and 2017 were included (minimum follow-up: 2 years, minimum age: 60 years). The assessment tools used for functional findings were range of motion (ROM), Visual Analogue Scale, absolute (CS) plus normative Constant Score, QuickDASH, and Subjective Shoulder Value. All adverse events as well as the radiological results and their clinical correlations were statistically analysed (using p < .05and 95% confidence intervals). RESULTS: Following fracture RSA, 68 patients were included (mean age: 72.5 years, mean follow-up: 46 months). Forty-two underwent primary RSA (PRSA), and 26 underwent revision RSA (SRSA). Adverse advents were observed in 13% (n = 9/68). No statistically significant results were found for the scores of the PRSA and SRSA groups, while the failed osteosynthesis SRSA subgroup obtained statistically significantly negative values for ROM subzones (flexion: p = .020, abduction: p = .020). Decreased instances of tubercle healing were observed for the in PRSA group relative to the SRSA group (p = .006). The absence of bony healing of the tubercles was related to significant negative clinical and subjective outcomes (all scores: p < .05, external rotation: p= .019). Significant postoperative improvements were evaluated in the SRSA group (CS: 23 to 56 at mean, p = .001), the time from index surgery to operative revision revealed no associations in functional findings. CONCLUSIONS: RSA is an effective option in severe shoulder fracture management with predictable results for salvage as well as first-line treatment. Promising mid-term functional results, reasonable implant survival rates, and high patient satisfaction can be achieved. LEVEL OF EVIDENCE: Level III.

Plastic recycling in a circular economy; determining environmental performance through an LCA matrix model approach.

To ensure a circular economy for plastics, insights in the environmental impacts of recycling and optimal recycling choices for specific plastic polymers are crucial. This was obtained by determining the environmental performance of 10 selected recycling technologies with varying TRL levels, using the chemical properties of the top 25 produced polymers in Europe. The results were collected in a life cycle assessment (LCA) 'matrix' model. To simulate realistic plastic recycling challenges, case studies of PE/PP foils from municipal waste and ABS plastic with brominated flame retardants were developed, to be used as an addition to the LCA matrix model results. Potential emission reduction was assessed by combining LCA matrix outcomes with European polymer demand data. The LCA matrix model illustrates that potential environmental performance of recycling technologies varied strongly per polymer type and did not always follow the state-of-the-art recycling hierarchy. Commodity plastics performed well with tertiary recycling technologies, such as gasification and pyrolysis to monomers; secondary mechanical recycling was outperformed. A focus on primary recycling is environmentally beneficial for most engineering and high performance plastics. To enhance the performance of primary recycling technologies, a higher purity and improved sorting is required. As demonstrated in the case studies, low sorting efficiencies due to impurities reduces positive environmental impacts. Hence, optimal environmental performance of recycling is obtained where pre-treatment (sorting, cleaning) is adapted to the recycling technology. According to the model, recycling the 15 most demanded polymers in Europe reduces CO2 emissions from plastics by 73% or 200 Mtonne CO2 eq.

Dorsal minimally invasive plate osteosynthesis of the distal tibia with regard to adjacent anatomical characteristics.

INTRODUCTION: The aim of this study was to perform MIPO of the distal tibia from a dorsomedial and dorsolateral approach and to evaluate their feasibility and risk of injury to adjacent anatomical structures. MATERIAL & METHODS: A total of 18 extremities from 9 adult human cadavers was included in the study. In each cadaver, one lower leg underwent application of a 12-hole 3.5 LCP metaphyseal plate from the medial and the further one from the lateral approach. For the medial approach, a 4 cm skin incision was performed at the tibial border of the Achilles tendon, starting from 1 cm proximal to its insertion point at the calcaneal tuberosity. Entrance was gained between the medial border of the flexor hallucis longus tendon and the medial neurovascular bundle. Regarding the lateral approach, the skin was incised over a length of about 4 cm at the lateral border of the Achilles tendon, approximately 1 cm proximal to its insertion point. Entrance was gained between the Achilles tendon and the peroneus brevis muscle. The plates were inserted in direct bone contact in a proximal direction and the proximal and distal ends were fixed. During dissection, the proximal and distal holes beneath the crossing points of the neurovascular bundle and the plate were noted. The distal and proximal intersection points of the neurovascular bundle and the plate were measured with reference to the distal border of the plate. RESULTS: Concerning the medial approach, the neurovascular bundle was on median located between the 6th and 11th plate holes starting from distal. The bundle intersected the plate distally at a mean height of 65.8 mm and proximally at 156.8 mm on average. For the lateral approach, the neurovascular bundle was situated between the 6th and the 12th plate hole from distal. It crossed the plate distally at a mean of 61.0 mm and proximal at a mean height of 153.9 mm. In none of the cases, lacerations of the neurovascular bundle were observed. CONCLUSION: In conclusion, MIPO from the dorsomedial and dorsolateral approach are both safe procedures as indicated by our study.

Medial minimally invasive helical plate osteosynthesis of the distal femur - a new technique.

INTRODUCTION: The goal of this study was to evaluate distal femoral minimally invasive plate osteosynthesis (MIPO) from a distal medial approach by use of a pre-bent helical implant. MATERIAL & METHODS: A total of 18 lower extremities was evaluated. A 29.6 cm steel plate was constructed and pre-bent on bone specimens with a torsion of 55.7° A 5 cm incision was performed from the tip of the medial epicondyle alongside its centre in a proximal direction. The medial border of the vastus medialis was retracted anteriorly. The level of the proximal skin incision was determined using the length of the pre-bent plates. The proximal incision was performed at a length of 4 cm at the described height at a line between the lateral epicondyle and the tip of the greater trochanter. A raspatory was advanced beneath the vastus medialis in a proximal direction to create an extraperiosteal tunnel for plate insertion. The plate was fixed to the bone at its proximal and distal portion via screws. Following dissection, the distance between the nearest perforator to the proximal plate end was evaluated. The vertical distances between the medial border of the plate and the femoral artery and femoral nerve were measured at the level of the proximal plate end and at the level of the proximal margin of the vastoadductor membrane. RESULTS: The most proximal perforating artery was located at a mean distance of 20.15 mm starting from the proximal plate margin. The mean interval between the medial border of the plate at the level of its proximal tip and the femoral artery was 51.9 mm. The average distance between the femoral nerve and the medial border of the proximal part of the plate was 42.3 mm. Regarding the interval between the medial border of the plate and the femoral artery, this was at a mean of 40.5 mm at the level of the proximal margin of the vastoadductor membrane. During dissection, none of the specimens showed any lesions of the adjacent anatomical characteristics. CONCLUSION: Our results indicate MIPO of the distal femur from a medial approach as a safe technique.

The 2-2-2-20-20 concept for supraacetabular schanz screw insertion without additional radiography.

PURPOSE: Application of supraacetabular Schanz screws is usually performed under image intensifier guidance. The aim of this study was to perform it without imaging, with the hypothesis that, respecting anatomical landmarks, pre- and intraoperative fluoroscopy can be avoided. MATERIAL & METHODS: Insertion of the supra-acetabular Schanz screws was performed by two trauma surgery residents in a study sample of 14 human adult cadavers which had been embalmed by use of Thiel`s method. With cadavers placed in supine position, the anterior superior iliac spine (ASIS) was palpated. Starting from this landmark, 2 cm were measured in a distal and 2 cm in the medial direction. At this point, a 2 cm long oblique skin incision was performed. Through this approach, 150 mm Schanz screws were drilled bilaterally into the supra-acetabular corridor with an angulation of 20° to distal as well as 20° to medial. Following screw application, combined obturator oblique-outlet views (COOO) were taken bilaterally in each specimen by use of an Arcadis© Orbic 3D C-arm to prove the screw position. Six of the specimens underwent a 3D-CT-scan. Images were evaluated concerning correct screw positioning by a further traumatologist. Skin and subcutaneous tissues were removed in the ilioinguinal region and possible lesions to the lateral femoral cutaneous nerve (LFCN) or to the joint capsule were evaluated. RESULTS: The sample consisted of eight pelves from female and six pelves from male cadavers. During radiographic evaluation of the COOO-scans (14 specimens) and the 3D-scans (6 specimens), the Schanz screws were placed inside the supra-acetabular corridor in all specimens (14/14). During dissections, no intracapsular screw placements or LFCN lesions were found. CONCLUSION: According to the described anatomical data, we defined a 2-2-2-20-20 concept, starting with a 2 cm skin incision 2 cm distal and 2 cm medial to the ASIS with a drill angulation of 20° inferior and 20° lateral orientation. Using this technique, all Schanz screws could be sufficiently inserted without intraprocedural x-ray imaging.

A cavity optomechanical locking scheme based on the optical spring effect.

We present a novel locking scheme for active length-stabilization and frequency detuning of a cavity optomechanical device based on the optical spring effect. The error signal is generated by utilizing the position measurement of a thermally driven intra-cavity nanomechanical device and employing its detuning-dependent frequency shift caused by the dispersive coupling to the cavity field. The scheme neither requires external modulation of the laser or the cavity nor does it demand for additional error signal readout, rendering its technical implementation rather simple for a large variety of existing optomechanical devices. Specifically, for large-linewidth microcavities or in situations where other locking schemes appear unfavorable conceptually or are hard to realize technically, the optical spring lock represents a potential alternative for stabilizing the cavity length. We explain the functional principle of the lock and characterize its performance in terms of bandwidth and gain profile.

[Quality of indications in bariatric surgery]. / Indikationsqualität in der Adipositaschirurgie.

Bariatric and metabolic surgery is increasingly being utilized in Germany and also worldwide. Due to the increased perioperative risk compared to non-obese patients, a detailed and accurate preoperative assessment of the patient is pivotal to improve postoperative and long-term outcomes. The indications for bariatric surgery have shifted in recent years from a certain body mass index (BMI) to comorbidity-based indications. In 2018 the German S3 guidelines for metabolic surgery defined the indications for bariatric surgery as well as the preoperative assessment. The indications for bariatric metabolic operations should be assessed by an interdisciplinary team consisting of surgeons, internists, diabetologists, psychologists and dietitians. It is paramount that surgeon and patient define realistic goals of these operations. Also, the different types of bariatric operation and their long-term consequences should be discussed. Additionally, a thorough endocrinological assessment by an internist or diabetologist with respect to relevant comorbidities of obesity as well as the adjustment of existing therapies are important. An assessment by a mental health professional is also mandatory; however, psychological comorbidities are not a contraindication as long as the patient is being treated and the disease is controlled. A preoperative short-term high-protein and low-carbohydrate fluid nutrition helps to reduce the risk of postoperative complications, especially for patients with a high BMI. A preoperative weight loss in the sense of a mandatory loss of a defined proportion of the body weight is not useful.

Prophylactic enlargement of the thecal sac volume by spinal expansion duroplasty in patients with unresectable malignant intramedullary tumors and metastases prior to radiotherapy.

Unresectable malignant intramedullary tumors and metastases usually require radiotherapy which intensifies spinal cord edema and might result in neurological decline. Spinal expansion duroplasty before radiotherapy enlarges the intrathecal volume and might thus prevent neurological deficits. The study aims to evaluate the clinical course of patients undergoing expansion duroplasty. This retrospective analysis (2007-2016) included all patients with unresectable intramedullary tumors who underwent spinal expansion duroplasty. To assess the degree of preoperative cord enlargement, we calculated the "diameter ratio": diameter of the spinal cord below and above the tumor / diameter of the tumor × 2. The presence of perimedullary cerebrospinal fluid (CSF) at the affected levels was analyzed on the preoperative magnetic resonance imaging (MRI). We recorded the occurrence of neurological deficits, wound breakdown, and CSF fistula. We screened 985 patients, 11 of which were included. Eight patients had an intramedullary metastasis, three patients a spinal malignant glioma. A diameter ratio ≤ 0.8 representing a significant preoperative intramedullary enlargement was seen in 10 cases (90.9%). Postoperative imaging was available in 9 patients, demonstrating successful decompression in 8 of the 9 patients (88.9%). The postoperative course was uneventful in 9 patients (81.8%). Mean overall survival was 13.4 (SD 16.2) months. Spinal expansion duroplasty prior to radiotherapy is a previously undescribed concept. Despite neoadjuvant radiation, no wound breakdown or CSF fistula occurred. In unresectable intramedullary tumors and metastases, spinal expansion duroplasty seems to be a safe procedure with the potential to prevent neurological decline due to radiation-induced cord swelling.

Sources, transport, and accumulation of different types of plastic litter in aquatic environments: A review study.

Types of plastic waste in different aquatic environments were assessed to obtain a global framework of plastic waste transport and accumulation, relevant for plastic pollution mitigation strategies in aquatic environments. Packaging and consumer products were the most encountered product categories in rivers, while fishery items dominated in the oceanic environment. Plastics from electronics, building and construction, and transport were barely observed. For polymers, polyethylene and polypropylene contributed most to pollution in all environments. The highest diversity in polymer composition was found in oceanic and freshwater sediments. It is therefore argued that a large fraction of plastic waste accumulates here. This confirms that plastic waste transport and accumulation patterns were most affected by the density, surface area, and size of plastics. Only thick-walled, larger plastic debris from low-density polymers are transported through currents from rivers to ocean, while the larger fraction of plastic litter is likely retained in sediments or beaches.

Evaluation of fine organic mixtures for treatment of acid mine drainage in sulfidogenic reactors.

The performance of passive biochemical reactors in acid mine drainage (AMD) treatment could be enhanced by using fine organic substrates in new reactor designs, such as diffusive exchange reactors. This work evaluated the effect of fine cellulosic components in organic mixtures and of enrichment with inoculum, on sulfate and metals removal in discontinuous cultures for three types of synthetic AMD. The cellulosic substrates evaluated were sawdust, microcrystalline cellulose, and forestry cellulose fibers, supplemented with cow manure and leaf compost. Using microcrystalline cellulose and forestry cellulose fibers with the less concentrated AMD, high sulfate reduction rates (73 mg/L-d and 58.2 mg/L-d, respectively) were achieved. Correspondingly, iron concentrations were reduced by 69% and 86.6%. Based on their higher sulfate reducing capacity, cellulose fibers obtained as fiber boards from a local kraft pulp mill were selected for treating a synthetic AMD with a high copper concentration (273 mg/L) and pH 4.94. In batch culture, low sulfate reducing activity (13.10 mg/L-d) was only observed at the highest substrate/AMD ratio (0.5:10) tested. Results show that the use of forestry cellulose fibers in reactive mixtures supplemented with inoculum could be an alternative for optimization of diffusive exchange reactors for AMD treatment.

Effects of moderate and severe arterial hypotension on intracerebral perfusion and brain tissue oxygenation in piglets.

BACKGROUND: Hypotension is common in anaesthetised children, and its impact on cerebral oxygenation is unknown. The goal of the present study was to investigate the effects of moderate systemic arterial hypotension (mHT) and severe hypotension (sHT) on cerebral perfusion and brain tissue oxygenation in piglets. METHODS: Twenty-seven anaesthetised piglets were randomly allocated to a control group, mHT group, or sHT group. Cerebral monitoring comprised a tissue oxygen partial pressure ( [Formula: see text] ) and laser Doppler (LD) perfusion probe advanced into the brain tissue, and a near-infrared spectroscopy sensor placed over the skin measuring regional oxygen saturation (rSO2). Arterial hypotension was induced by blood withdrawal and i.v. nitroprusside infusion [target MAP: 35-38 (mHT) and 27-30 (sHT) mm Hg]. Data were analysed at baseline, and every 20 min during and after treatment. RESULTS: Compared with control, [Formula: see text] decreased equally with mHT and sHT [mean (SD) after 60 min: control: 17.1 (6.4); mHT: 6.4 (3.6); sHT: 7.2 (4.3) mm Hg]. No differences between groups were detected for rSO2 and LD during treatment. However, in the sHT group, rSO2 increased after restoring normotension [from 49.3 (9.5) to 58.9 (8.9)% Post60]. sHT was associated with an increase in blood lactate [from 1.5 (0.4) to 2.4 (0.9) mmol L-1], and a decrease in bicarbonate [28 (2.4) to 25.8 (2.6) mmol L-1] and base excess [4.7 (1.9) to 2.0 (2.7) mmol L-1] between baseline and 60 min after the start of the experiment. CONCLUSIONS: Induction of mHT and sHT by hypovolaemia and nitroprusside infusion caused alterations in brain tissue oxygenation in a piglet model, but without detectable changes in brain tissue perfusion and regional oxygen saturation.