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In the era of limited energy resources, researchers and scientists are highlighting bioenergy or biomass energy as a sustainable form of renewable and upgradable energy source. Hydrothermal liquefaction, known as HTL, is a thermochemical conversion process which produces mainly biocrude, from several biomass types: microalgae, waste water, crops, etc. Commercializing HTL and upscaling it for industrial applications needs intensive studies for building continuous systems. This work defines the HTL of biomass, including the major components of a continuous system: feeding system, heating system, reactor and separator. Many previous studies are compared to investigate the effect of operating parameters; residence time, temperature, pressure, flow rate, catalyst and co-solvent types on the products' qualities and quantities. In addition, using data from previous HTL studies, a new analytic study concerning the effect of the biomass composition on the optimum temperature of liquefaction and the maximum yield of biocrude is presented and the results show the effect of the biomass used on these values. Although, using previous works of continuous HTL systems, this work presents all the aspects of continuous processing, including the hardware used and the parameters involved in the hydrothermal processing of biomass. In addition, a transition phase from batch to continuous processing, re-defining the variables needed for the design, is proposed. The analysis of the biomass components and the operating parameters effects, and, the proposed transition phase will be used to select and calibrate the suitable conditions for designing and constructing a large scale continuous HTL system. [Display omitted] • State of the art is set on continuous hydrothermal processes design. • Construction materials and heating modes are discussed. • Operating parameters effects on products of continuous systems discussed. • Effects of feeding characteristics on products discussed. • Effects of catalysts and solvents are discussed. [ABSTRACT FROM AUTHOR]

Aim We analysed cortical muscle representation areas during single muscle activation and during the co-activation of several upper arm muscles in the patients with writer's cramp to determine the possible occurrence of abnormal dynamic somatotopic changes in M1, in addition to the static map abnormalities already described in this form of dystonia. Methods Using transcranial magnetic stimulation, we assessed cortical representations of medial deltoid, extensor carpi radialis and the first dorsal interosseus muscles in eight patients with writer's cramp and in eight healthy control subjects. Cortical maps were obtained during distal muscles' activation either in isolation or in conjunction with voluntary medial deltoid co-activation. Results This study showed a difference in the organization of cortical representations of these muscles between the patients with dystonia and control subjects. The first dorsal interosseus and the extensor carpi radialis cortical representation areas were larger in the dystonic group. The cortical representations became larger when the medial deltoid was simultaneously co-activated, and this effect was not observed in the control group. In the dystonic group, the three cortical muscle representations largely overlapped and their centres of gravity were closer. Conclusion Patients with dystonia showed not only a different spatial organization of muscle cortical representation areas, but also abnormal acute somatotopic changes during proximal muscle co-activation. Task-specific motor impairment in writer's cramp may result not only from lack of cortical inhibition and the well-known anomalous cortical organization observed in these patients, but also from abnormal patterns of proximo-distal functional muscle coupling. [ABSTRACT FROM AUTHOR]

Aim: The aim of this work was to analyse how writer's cramp patients coordinate each element of the proximal to distal upper arm muscle chain during voluntary movement. Methods: Using transcranial magnetic stimulation, we have assessed motor cortex excitability properties in patients by recording motor-evoked potentials and silent periods in both the extensor carpi radialis (ECR) and the first dorsal interosseus muscles (FDI), activated either in isolation, or in conjunction with voluntary medial deltoid (MD) co-activation during performance of precise tasks. Ten dystonic patients and ten healthy controls were tested. Results: In both test groups, the ECR muscle displayed a similar active motor threshold, but the excitability curves reached higher plateau values, when the proximal MD muscle was co-activated. In the dystonic group, the FDI muscle excitability curves reached higher plateau values when the MD was co-activated, whereas co-activation had no effect on the control group. In the control group, silent periods, in both the ECR and the FDI were longer when the MD was co-activated. This effect was not observed in the dystonic group. Conclusion: In the dystonic group, facilitation of the FDI was observed during a task involving proximo-distal coordination. No differences in silent periods were observed when the muscle was activated alone. Our results suggest that such abnormal facilitation is not only an impairment of the central inhibitory mechanisms reported for dystonic patients, but, in addition, represents true abnormality in cortical muscle activation strategies. [ABSTRACT FROM AUTHOR]

Background – Primary cranial dystonia (PCD) is related to a functional disorder in basal ganglia usually accompanied by impaired executive function. Aim – To investigate symptom relief and neurocognitive change in response to treatment with botulinum toxin (BTX) in a group of patients with PCD. Methods – We assessed nine patients with PCD and nine age- and educationally matched healthy individuals using tests of memory, sustained attention, span of auditory attention, and perceptual flexibility. Results – Despite well-preserved intellectual skills relative to controls, we identified a sustained attention deficit in patients with PCD. After BTX treatment, there was an increase in the scores of the concentration endurance test (sustained attention) and the values did not differ significantly from control group patients’ scores. Conclusion – The results support the view that executive dysfunction in PCD is secondary to the disrupting effects of the symptoms. Treatment with BTX alleviates the symptoms and, consequently, improves sustained attention. [ABSTRACT FROM AUTHOR]

Ten mycoplasmas were isolated from 130 nasopharyngeal swabs from thoroughbred horses with acute respiratory disease and three from 198 apparently normal horses. Two mycoplasmas were isolated from 21 tracheal swabs taken at necropsy. These mycoplasmas, together with six isolated from the equine respiratory tract by other workers, were subjected to biochemical and serological tests. Other properties examined in certain representative strains were appearance under the electron microscope, ability to adsorb or agglutinate the erythrocytes of various animal species and the electrophoretic pattern of the cell proteins.On the basis of these tests, mycoplasmas from the equine respiratory tract were divided into seven species. Three species belonged to the genus Acholeplasma, members of which do not require sterol for growth, and were identified as A. laidlawii, A. oculi (formerly A. oculusi) originally isolated from the eyes of goats, and a recently named species A. equifoetale, previously isolated from aborted equine fetuses.Of the four sterol-dependent Mycoplasma species, one was identified as M. pulmonis, a common rodent pathogen. Another cross-reacted serologically with M. felis and should probably be classified as that species. The other two species probably represent new species peculiar to the horse. One of these, represented by the strains N3 and N11, ferments glucose and is serologically distinct from 19 recognized species of glucose-utilizing mycoplasmas and from two species which do not metabolize either glucose or arginine. The other species, represented by four strains, hydrolyses arginine and, because it is serologically distinct from all the named arginine-hydrolysing Mycoplasma species, the name M. equirhinis sp.nov. is proposed for it.Of the seven species, only M. pulmonis and the glucose-utilizing species represented by N3 and N11 were found exclusively in horses with acute respiratory disease. A. oculi was isolated from an apparently normal horse. The other four species were found in normal horses as well as those with respiratory disease, although three out of the four strains of M. equirhinis were from sick horses. [ABSTRACT FROM PUBLISHER]