Magnetic Resonance Elastography of the Brain Using an Ergonomic Driver: Assessment of Scan-Rescan Reproducibility

Magnetic resonance elastography (MRE) allows the visualization of displacement patterns from induced harmonic mechanical waves propagating in tissue. Strain and mechanical properties can be computed from these displacement patterns. Mechanical properties of tissue are affected by various disease processes. MRE has shown brain tumor to differ in stiffness in comparison to normal tissue. MRE is currently being offered as an upgrade on most conventional MRI scanners. However, the actuator supplied by vendors is a drum driver designed primarily for hepatic MRE scan. The goals of the project was to design and build an ergonomic flexible driver for use in MRE of the brain, to assess the Scan-Rescan reproducibility of shear modulus measurements, and to investigate the relationship between shear modulus measurements and driver frequency. An ergonomic flexible driver was constructed to induce mechanical waves in the brain. MRE of the brain was performed in 10 healthy volunteers. MRE data was collected at frequencies of 60 Hz, 50 Hz, and 40 Hz. After the scans were completed, the subjects were removed from the table, and then repositioned and rescanned using the same process. All subjects were scanned and rescanned within an hour. The within-subject coefficient of variance (CV) and inter-subject CV were calculated for shear modulus measurements of white matter, grey matter, and whole brain. A one-way analysis of variance (ANOVA) was applied to test for any difference between shear modulus measurements made at different frequencies. The within-subject CVs of white matter, grey matter, and whole brain shear modulus measurements for all frequencies ranged from 3.7-4.1%, 4.7-6.0%, and 1.8-3.5% respectively. A significant statistical difference was found between measurements made at different frequencies. This study demonstrated the ability to make in vivo shear modulus measurements of brain tissue. MRE was shown to be able to differentiate white matter from grey matter using the shear modulus. Measured white and grey matter shear modulus values were within the range of values reported in literature. A dependence of shear modulus measurements on frequency was observed; Standardization of MRE imaging parameters is recommended to facilitate the interpretation of brain MRE results

ANALISIS YURIDIS RESIKO PEMALSUAN TERHADAP PENGADAAN SERTIFIKAT ELEKTRONIK DI INDONESIA

ABSTRACThe issuance of Ministerial Regulation of ATR BPN Number 1 of 2021 concerning Electronic Certificates is a progressive regulation with the intention of replacing conventional certificates with electronic certificates, this is based on minimizing counterfeiting efforts by land mafias so that the implication is that the number of land disputes in the field will decrease. However, the discourse for modernizing proof of ownership is in line with the increasing development of crime in the electronic (digital) world, therefore the study of the risk of counterfeiting the procurement of electronic certificates is the focus of this research. This research is a normative legal research, which is carried out by examining library materials, which are secondary data and statutory regulations as primary legal materials. This research is a case law approach, legislation, approach, conceptual approach. Based on the research, several legal issues were found, namely, What is the procedural mechanism in procuring electronic certificates according to Agrarian and Spatial Planning Number 1 of 2021? What is the risk of falsification of electronic certificate data according to criminal law?Keywords :Electronin Certificate, Risk, Counterfeiting ABSTRAKDiterbitkannya Peraturan Menteri ATR BPN Nomor 1 Tahun 2021 Tentang Sertifikat Elektronik adalah peraturan bersifat progresif dengan maksud untuk mengganti sertifikat konvensional menjadi sertifikat elektronik, hal ini didasari untuk memperkecil upaya pemalsuan oleh para mafia tanah sehingga implikasinya adalah menurunnya angka sengketa tanah di lapangan. Namun wacana untuk modernisasi bukti kepemilikan ini sejalan dengan meningkatnya perkembangan kejahatan di dunia elektronik (digital), oleh sebab itu kajian resiko pemalsuan terhadap pengadaan sertifikat elekronik menjadi fokus penelitian ini. Penelitian ini adalah penelitian hukum normatif, yang dilakukan dengan cara meneliti bahan pustaka, yang merupakan data sekunder dan aturan perundang-undangan sebagai bahan hukum primer. Penelitian ini Pendekatan Kasus hukum, Perundang-perundangan, Pendekatan, Pendekatan Konseptual. Berdasarkan penelitian tersebut ditemukan beberapa isu hukum yakni, Bagaimana mekanisme prosedural dalam pengadaan sertifikat elektronik menurut Peraturan Agraria dan Tata Ruang Nomor 1 tahun 2021? Bagaimana resiko terjadinya pemalsuan data sertifikat elektronik menurut hukum pidana?Kata kunci : Sertifikat Elektronik, Resiko, Pemalsua

CONTRIBUTION À L’ÉTUDE DE LA BIOACCUMULATION MÉTALLIQUE DANS LES SÉDIMENTS ET LES ORGANISMES AQUATIQUES DU LITTORAL DE SAIDIA (MAROC ORIENTAL)

The result of the coastal metal contamination in the extreme East of Morocco was based on sampling and the search for metal contamination by lead, zinc, cadmium, and iron respectively. This search was done in marine water, sediments, and in the sea. Urchin Paracentrotus lividus; benthic echinoderm is common in the eastern Mediterranean coast of Morocco with two sampling series (July 2011 and March 2012). The objective of this study is to evaluate the distribution of some heavy metals in the Saidia coastline, through the Biological indicator, Paracentrotus lividus. The heavy metal content (iron, zinc, lead and cadmium) in water, sediment, and marine organisms, were studied in four stations at the coast Saidia. The study revealed the presence of very high concentrations of metals, especially with regard to iron and zinc. Lead has relatively high values, while the cadmium is virtually absent in all samples. However, the results support a finding which is similar to the bio-accumulated metals by the sea urchin elements and those detected in water and sediment. The existence of a significant correlation between iron, zinc, and lead shows that there is a high chemical affinity between these three metals. Overall, this study allows us to identify the presence of heavy metals in water, sediment, and aquatic organisms of coastal Saidia, which is seriously disrupted by various domestic discharges, port, industrial and agricultural wastes

The Use of Feedback in Classroom Interaction in Moroccan Primary School

This study explores the verbal feedback utilized by a group of Moroccan primary school teachers. The intent is to identify feedback types used and how effective they are in building knowledge and scaffolding thinking. The theoretical framework underpinning this study is embedded within the sociocultural perspective that conceptualizes the classroom as a cultural location of meaning in which relationships, functions, regulations, values, and norms are socially constructed. The study draws on observation data in large-class settings. Twenty two teachers from five different schools took part in the study. Twenty two lessons covering a range of subjects and topics were observed. Verbal manuscripts of classroom discourse were analyzed qualitatively. The analysis of the transcripts revealed that although four different types of feedback were identified, there was little variation in teacher provision of feedback. One particular form was preponderant— evaluative feedback. Interactional issues related to encouraging student responses and thinking are also addressed. Findings reveal that teachers infrequently offer the types of feedback interventions categorized as effective in improving learning during typical classroom interactions. These results are important as they provide an awareness of the feedback practices employed in the observed classrooms and the significant effects they have on classroom interaction and student learning. We conclude by highlighting consequences of these findings on professional development, and offer opportunities for future research

Policies in Activity-based Flexible Offices -‘I am sloppy with clean-desking. We don’t really know the rules.’

Activity-based Flexible Offices (A-FOs) are offices with unassigned desks that provide a variety of workspaces. This paper presents desk-sharing and speech rules identified in A-FOs in four Swedish organisations, the emergence of and compliance with these rules, and their consequences for work conditions. Data collection involved 105 semi-structured interviews, document analyses, and observations. The identified rules were: (1) to remove belongings, (2) temporal restrictions on using the same workstations, (3) temporal restrictions on using scarce zones, (4) restrictions on verbal interactions, and (5) restrictions on phone conversations. The cases with extensive user involvement in their planning process had explicit unambiguous rules. A better compliance with rules occurred when (i) the employees were well-prepared and had a unified understanding regarding how and why to follow the rules, (ii) the rules were explicitly communicated and were regarded as easy to follow, and (iii) following the rules facilitated work and improved work conditions

Study of Flow and Energy Dissipation in Stepped Spillways

We present in this work the quantitative and qualitative study of the flow in the stepped spillways. The experimental measurement is realized on the reduced model. Different flow configurations on a spillway are described. New experimental results linked to the flow aspect and to the energy dissipation after the passage over the spillway are presented. The experimental results relative to the energy dissipation are analysed. They are compared thereafter to the results of the experiences and models found in other research works

Policies for sharing workspaces in activity-based flex offices

Policies for maintaining non-territoriality (desk-sharing and clean desk policies) and for maintaining zones with different sound levels vary between activity-based flex offices. Five policies were identified as crucial for making the activity-based office concept work. In cases without explicitly expressed policies employees reported uncertainties and interpretations of how to act in the office

Numerical analysis of bonded composite patch efficiency in the case of lateral U and V-notched aluminium panels

In this study, the finite element method is applied to investigate the mechanical behavior of aluminium notched structures reinforced by composite patch. In order to evaluate the efficiency of patches in the case of lateral semicircular and V-notches, it is very important to analyze the stress distribution at the notch tip and to take in consideration the influence of the geometrical and mechanical properties of the patch and the adhesive. Simple and double patch were used as reinforcement techniques. Results showed that the stress concentration factor is reduced at the notch tip by using a double patch reinforcement. This reduction becomes more noticeable when the patch thickness increases