Air gasification of digestate and its co-gasification with residual biomass in a pilot scale rotary kiln

In this study energy recovery of digestate from a biogas plant was investigated via air gasification. Gasification tests were executed in a pilot scale rotary kiln plant having a nominal biomass feeding rate of about 20 kg/h. The equivalence ratio was varied from 0.22 to 0.39 with the goal to approach the autothermal condition. Tests were carried out for 5 h in steady state condition. Syngas composition, char and gas yields were measured. To improve the cold gas efficiency of the process, a mixture of digestate and almond shells (60:40 wt%) was gasified. Autothermal condition was reached with the mixture using equivalence ratio of 0.30 where the corresponding cold gas efficiency achieved the maximum value of 55%. The raw gas had a lower heating value of 4–5 MJ/Nm3. To evaluate possible improvements in the produced gas properties, in this work the effect of steam injection was also investigated

Smaller spared subcortical nuclei are associated with worse post-stroke sensorimotor outcomes in 28 cohorts worldwide

Up to two-thirds of stroke survivors experience persistent sensorimotor impairments. Recovery relies on the integrity of spared brain areas to compensate for damaged tissue. Deep grey matter structures play a critical role in the control and regulation of sensorimotor circuits. The goal of this work is to identify associations between volumes of spared subcortical nuclei and sensorimotor behaviour at different timepoints after stroke. We pooled high-resolution T1-weighted MRI brain scans and behavioural data in 828 individuals with unilateral stroke from 28 cohorts worldwide. Cross-sectional analyses using linear mixed-effects models related post-stroke sensorimotor behaviour to non-lesioned subcortical volumes (Bonferroni-corrected, P < 0.004). We tested subacute (≤90 days) and chronic (≥180 days) stroke subgroups separately, with exploratory analyses in early stroke (≤21 days) and across all time. Sub-analyses in chronic stroke were also performed based on class of sensorimotor deficits (impairment, activity limitations) and side of lesioned hemisphere. Worse sensorimotor behaviour was associated with a smaller ipsilesional thalamic volume in both early (n = 179; d = 0.68) and subacute (n = 274, d = 0.46) stroke. In chronic stroke (n = 404), worse sensorimotor behaviour was associated with smaller ipsilesional putamen (d = 0.52) and nucleus accumbens (d = 0.39) volumes, and a larger ipsilesional lateral ventricle (d = -0.42). Worse chronic sensorimotor impairment specifically (measured by the Fugl-Meyer Assessment; n = 256) was associated with smaller ipsilesional putamen (d = 0.72) and larger lateral ventricle (d = -0.41) volumes, while several measures of activity limitations (n = 116) showed no significant relationships. In the full cohort across all time (n = 828), sensorimotor behaviour was associated with the volumes of the ipsilesional nucleus accumbens (d = 0.23), putamen (d = 0.33), thalamus (d = 0.33) and lateral ventricle (d = -0.23). We demonstrate significant relationships between post-stroke sensorimotor behaviour and reduced volumes of deep grey matter structures that were spared by stroke, which differ by time and class of sensorimotor measure. These findings provide additional insight into how different cortico-thalamo-striatal circuits support post-stroke sensorimotor outcomes

Complications of Radiotherapy and Radiosurgery in the Brain and Spine.

Radiation therapy is an integral part of the standard of care for many patients with brain and spine tumors. Stereotactic radiation surgery is increasingly being used as an adjuvant therapy as well as a sole treatment. However, despite newer and more focused techniques, radiation therapy still causes significant neurotoxicity. In this article, we reviewed the scientific literature, presented cases of patients who had developed different complications related to conventional radiation therapy or radiosurgery (gamma knife), demonstrated the imaging findings, and discussed the relevant clinical information for the correct diagnoses. Radiation therapy can cause injury in different ways: directly damaging the structures included in the radiation portal, indirectly affecting the blood vessels, and increasing the chance of tumor development. We also divided radiation complications according to the time of occurrence: acute (0 to 4 weeks), early delayed (4 weeks to months), and late delayed (months to years). With the increasing application of radiation therapy for the treatment of CNS tumors, it is important for the neuroradiologist to recognize the many possible complications of radiation therapy. Although this may cause significant diagnostic challenges, understanding the pathophysiology, time course of onset, and imaging features may help institute early therapy and prevent possible deleterious outcomes. Learning Objectives: To recognize the main complications of radiation therapy and stereotactic radiosurgery in the brain and spine, and to highlight the imaging findings to improve the diagnostic process and treatment planning

Longitudinal Changes in Cerebral Perfusion, Perivascular Space Volume, and Ventricular Volume in a Healthy Cohort Undergoing a Spaceflight Analog

Background and purpose: A global decrease in brain perfusion has recently been reported during exposure to a ground-based spaceflight analog. Considering that CSF and glymphatic flow are hypothesized to be propelled by arterial pulsations, it is unknown whether a change in perfusion would impact these CSF compartments. The aim of the current study was to evaluate the relationship among changes in cerebral perfusion, ventricular volume, and perivascular space volume before, during, and after a spaceflight analog. Materials and methods: Eleven healthy participants underwent 30 days of bed rest at 6° head-down tilt with 0.5% atmospheric CO2 as a spaceflight analog. For each participant, 6 MR imaging brain scans, including perfusion and anatomic-weighted T1 sequences, were obtained before, during, and after the analog period. Global perfusion, ventricular volume, and perivascular space volume time courses were constructed and evaluated with repeated measures ANOVAs. Results: Global perfusion followed a divergent time trajectory from ventricular and perivascular space volume, with perfusion decreasing during the analog, whereas ventricular and perivascular space volume increased (P < .001). These patterns subsequently reversed during the 2-week recovery period. Conclusions: The patterns of change in brain physiology observed in healthy participants suggest a relationship between cerebral perfusion and CSF homeostasis. Further study is warranted to determine whether a causal relationship exists and whether similar neurophysiologic responses occur during spaceflight