INFLUENCE OF SCREENING BLOCK SUPPORTING WAY ON THE BEHAVIOUR OF A SOLID PARTICLE ON AN OSCILLATING SURFACE

This article shows a study aiming to identify the influence carried out by the supporting way of the working surface in the case of plane oscillating screening device, over the behavior of a solid particle. In order to achieve this, a theoretical study has been conducted by using a simulation program, Working Model 2D, within which two ways of supporting the screening block have been conceived: the working surface supported by tie-rods, and the surface suspended on tie-rods. Following the simulation, a series of physical parameters has been determined: the trajectory followed by the solid particle; the circuit of the solid particle during its movement on the working surface; the acceleration of the solid particle and the reaction force occurred between the solid particle and the working surface. Following the analysis of resulting values it may be noted that the best way to support the working surface, as far as the efficiency of mechanical separation is concerned, according to width and thickness of the solid particle, is obtained in the case where the working surface is supported by tie-rods, since the running time of the working surface is the highest and it is 4.12 seconds, value generating the high average moving speed; the particle’s rotation angle is from -2 rad to +4.8 rad, having as a result the amplest possible rotation

INFLUENCE OF SCREENING BLOCK SUPPORTING WAY ON THE BEHAVIOUR OF A SOLID PARTICLE ON AN OSCILLATING SURFACE

This article shows a study aiming to identify the influence carried out by the supporting way of the working surface in the case of plane oscillating screening device, over the behavior of a solid particle. In order to achieve this, a theoretical study has been conducted by using a simulation program, Working Model 2D, within which two ways of supporting the screening block have been conceived: the working surface supported by tie-rods, and the surface suspended on tie-rods. Following the simulation, a series of physical parameters has been determined: the trajectory followed by the solid particle; the circuit of the solid particle during its movement on the working surface; the acceleration of the solid particle and the reaction force occurred between the solid particle and the working surface. Following the analysis of resulting values it may be noted that the best way to support the working surface, as far as the efficiency of mechanical separation is concerned, according to width and thickness of the solid particle, is obtained in the case where the working surface is supported by tie-rods, since the running time of the working surface is the highest and it is 4.12 seconds, value generating the high average moving speed; the particle’s rotation angle is from -2 rad to +4.8 rad, having as a result the amplest possible rotation

Latent Aggression and Impulsive Manifestations of the Psychiatric Patient. Clinical, Legal and Ethical Aspects

Psychiatry represents the medical branch that focuses not only on the patient’s mental state but also on general health issues and wellbeing. With the continuous development of human civilization, the individual no longer uses aggression, a counterproductive method for day to day living in the community, to meet its basic needs. Neurobiological changes that lead to aggressive manifestations are a medical problem only if the aggressive impulses occur in a person with a psychiatric diagnosis already established and poses a danger to himself and others. Aggressive behaviour due to a medical condition or biological factors is an old problem that has great forensic implications both for the patient and for the medical staff. Decreased quality of life, low emotional support and social marginalization are some of the repercussions that emerge. Understanding the negative effects of aggressive impulses found in multiple psychiatric diagnoses is the key to an optimal doctor-patient relationship. An individualized treatment is necessary, the final goal being social reintegration.</p

The Fetal Type of Posterior Cerebral Artery

Background and Objectives: Anatomical variations of the arterial circle of Willis (cW) are common. A posterior cerebral artery (PCA) fed mostly or exclusively from the internal carotid artery is a fetal PCA (FPCA), partial (p-FPCA), or full/complete (f-FPCA), respectively. Because FPCA occurs in different anatomical configurations of the cW sides, we aimed to document in detail these morphological possibilities of FPCA within the cW. Materials and Methods: FPCAs were documented on a retrospective set of 139 computed tomography angiograms. Results: FPCAs were found in thirteen cases, nine males and four females. In 7/13 cases there were two modified sides of the cW. In 5/13 cases there were three altered sides of the cW. Another case with FPCA showed four altered sides of the cW. In 10/13 cases, FPCA was unilateral and in the other three cases it was bilateral. Compared to the overall group, unilateral p-FPCAs were found in 1.43%, while unilateral f-FPCAs were found in 5.75%. A bilateral p-FPCA-f-FPCA combination was found in 0.71% and a bilateral f-FPCA-f-FPCA combination occurred in 1.43%. An anatomically isolated ICA was found in just one case with bilateral f-FPCA (0.71%). In 7/13 FPCA cases there were arterial variants exclusively in the posterior cW. In the other 6/13 FPCA cases, there were variants in both anterior and posterior circulation. There were no statistically significant associations of FPCA with sex or age. The higher prevalence of right-sided FPCA was not statistically significant. Conclusions: Anatomical assessments of cW should be performed on a case-by-case basis, as they may correspond to different cW morphologies

The Fetal Type of Posterior Cerebral Artery

Background and Objectives: Anatomical variations of the arterial circle of Willis (cW) are common. A posterior cerebral artery (PCA) fed mostly or exclusively from the internal carotid artery is a fetal PCA (FPCA), partial (p-FPCA), or full/complete (f-FPCA), respectively. Because FPCA occurs in different anatomical configurations of the cW sides, we aimed to document in detail these morphological possibilities of FPCA within the cW. Materials and Methods: FPCAs were documented on a retrospective set of 139 computed tomography angiograms. Results: FPCAs were found in thirteen cases, nine males and four females. In 7/13 cases there were two modified sides of the cW. In 5/13 cases there were three altered sides of the cW. Another case with FPCA showed four altered sides of the cW. In 10/13 cases, FPCA was unilateral and in the other three cases it was bilateral. Compared to the overall group, unilateral p-FPCAs were found in 1.43%, while unilateral f-FPCAs were found in 5.75%. A bilateral p-FPCA-f-FPCA combination was found in 0.71% and a bilateral f-FPCA-f-FPCA combination occurred in 1.43%. An anatomically isolated ICA was found in just one case with bilateral f-FPCA (0.71%). In 7/13 FPCA cases there were arterial variants exclusively in the posterior cW. In the other 6/13 FPCA cases, there were variants in both anterior and posterior circulation. There were no statistically significant associations of FPCA with sex or age. The higher prevalence of right-sided FPCA was not statistically significant. Conclusions: Anatomical assessments of cW should be performed on a case-by-case basis, as they may correspond to different cW morphologies

A New Classification of the Anatomical Variations of Labb&eacute;&rsquo;s Inferior Anastomotic Vein

(1) Background: The inferior anastomotic vein of Labb&eacute; (LV) courses on the temporal lobe, from the sylvian fissure towards the tentorium cerebelli and finishes at the transverse sinus (TS). The importance of the LV topography is related to skull base neurosurgical approaches. Based on the hypothesis of the existence of as yet unidentified anatomical possibilities of the LV, we aimed through this research to document the superficial venous topographic patterns at the lateral and inferior surfaces of the temporal lobe. (2) Methods: A retrospective cohort of 50 computed tomography angiograms (CTAs) of 32 males and 18 females was documented. (3) Results: Absent (type 0) LVs were found in 6% of cases. Anterior (temporal, squamosal&ndash;petrosal&ndash;mastoid, type 1) LVs were found in 12% of cases. LVs with a posterior, temporoparietal course (type 2) were found to be bilateral in 46% of cases and unilateral in 36% of cases. Type 3 LVs (posterior, parietooccipital) were found to be bilateral in 8% and unilateral in 32% of cases. In 24% of cases, duplicate LVs were found that were either complete or incomplete. A quadruplicate LV was found in a male case. On 78 sides, the LV drained either into a tentorial sinus or into the TS. (4) Conclusions: The anatomy of the vein of Labb&eacute; is variable in terms of its course, the number of veins and the modality of drainage; thus, it should determine personalized neurosurgical and interventional approaches. A new classification of the anatomical variations of Labb&eacute;&rsquo;s vein, as detected on the CTAs, is proposed here (types 0&ndash;3)

The Infraoptic or Infrachiasmatic Course of the Anterior Cerebral Artery Emerging an Elongated Internal Carotid Artery

(1) Background: The normal A1 segment of the anterior cerebral artery (ACA) has a supraoptic course. The proximal infraoptic course of an A1 segment leaving the internal carotid artery (ICA) near the origin of the ophthalmic artery is a rare possibility. This study aimed to determine the prevalence and detailed anatomy of infraoptic A1 segments. (2) Methods: We retrospectively studied 145 computed tomography angiograms from 92 male and 53 female cases, with ages varying from 61 to 78 y.o. (3) Results: In 21/145 cases, infraoptic or infrachiasmatic horizontal-medial courses of A1 segments that emerged distally from the ICA were found. Distal infraoptic A1 segments were bilateral in 16/145 cases and unilateral in 3/145 cases. Infrachiasmatic A1 segments were found bilaterally in 2/145 male cases. All the infraoptic/infrachiasmatic A1 segments left long ICAs with low bifurcations. In 7/34 sides with distal infraoptic or infrachiasmatic A1 segments, supracarotid courses were present. In one female, the right A1 segment had an anterior supraclinoid, supracarotid and infraoptic course. In two female cases with a bilateral distal infraoptic A1, the segment was almost contacting the respective posterior cerebral artery. (4) Conclusions: In cases with dolicho(ectatic) ICAs, the A1 segments could have infraoptic and supracarotid courses the neurosurgeons should be aware of