Cerebral microbleeds and cognitive impairment

Background: With increasingly ageing populations comes an increased prevalence of cognitive impairment and dementia. The pathophysiology behind dementia is still unknown, and there is no cure. Microscopic bleeds in the brain parenchyma, so called cerebral microbleeds, are common in ageing populations, as well as in dementia and stroke, and are primarily a marker of small vessel disease. Due to their high prevalence in memory clinic populations, microbleeds have been hypothesized to be of importance in the cognitive impairment disease process. Purpose: To cross-sectionally study the detection and clinical implications of cerebral microbleeds in cognitive impairment. Study I showed that microbleeds are common in cognitive impairment (22% prevalence), and especially in vascular dementia (59% prevalence). Microbleeds are associated with hypertension, male gender, high age, and increase with increasing risk factors. Topography of microbleeds is predominantly lobar and occipital in Alzheimer disease. The microbleed topography varies depending on underlying diagnosis and risk factors. Study II showed that susceptibility weighted imaging increases the prevalence and number of microbleeds detected on 3.0T magnetic resonance imaging. Inter-rater agreement of microbleeds is excellent on T2* and susceptibility weighted imaging, across raters of different experience. Only minor differences in clinical associations were noted across different sequences. Study III showed that amyloid β42 levels were lower in the cerebrospinal fluid with a high number of microbleeds. This was true in the whole cohort (n=1039), Alzheimer disease and mild cognitive impairment. In the whole cohort cerebrospinal fluid/serum albumin ratios were higher with increasing number of microbleeds. In multivariate regression analysis low amyloid levels in the cerebrospinal fluid with increasing number of microbleeds held true. White matter hyperintensities were likewise associated with low amyloid β42 levels, whereas lacunes were associated with higher amyloid levels in the cerebrospinal fluid. Study IV showed that lobar microbleeds are associated with lower amyloid β42 levels in the cerebrospinal fluid, in the whole cohort and Alzheimer disease. Deep and infratentorial microbleeds showed tendencies to be associated with higher amyloid and lower tau levels in the cerebrospinal fluid. Multivariable logistic regression analysis showed that white matter hyperintensities and lacunes were associated with lobar and deep microbleeds. Conclusions: Cerebral microbleeds are best detected with susceptibility weighted MRI and are common in a memory clinic. Microbleeds show varying associations based on topography. Especially lobar microbleeds are associated with low cerebrospinal fluid amyloid, and specifically in Alzheimer disease, suggesting that primarily lobar microbleeds may be of importance in cognitive impairment

Comparing The Effectiveness of Content-Based Language Instruction and Communicative Language Teaching in Improving the Reading Comprehension Skills of Iranian Intermediate English Learners

This study compares the effectiveness of content-based language instruction (CBLI) and communicative language teaching (CLT) in improving the reading comprehension skills of 60 primary and secondary school EFL students in Iran. Furthermore, it assesses Iranian EFL learners’ attitudes toward CLT and CBLI to examine which approach is more preferred and perceived as more effective by the L2 learners. The measures were two Cambridge Advanced English (CAE) reading comprehension tests administered as the pretest and posttest of an intervention study to measure the reading comprehension ability of the students in both groups who were instructed using CLT or CBLI approaches. During the intervention, the students in the CLT group were instructed by using CLT practices and the students in the CBLI group were instructed using CBLI principles for 15 weeks (30 sessions in total). : After having conducted the intervention study, the students in the two groups were surveyed about CLT and CBLI. The data shows that both CLT and CBLI were effective in improving the reading comprehension skills of the Iranian EFL learners as the learners who were instructed using each of these approaches did not show any significant differences in terms of reading comprehension skills compared to the other group. Moreover, the Iranian EFL students who received instructions through CLT perceived that the use of CLT was effective in improving their reading comprehension skills. Likewise, the students who were instructed using the CBLI principles favored the use of CBLI for teaching reading comprehension skills. While there are no significant differences of the two groups’ reading comprehension skills, the students in the CBLI group were overall more positive about CBLI compared to the students in the CLT group toward the use of CLT

Cyclic Fatigue Life of Two Single File Engine-Driven Systems in Simulated Curved Canals

Introduction: This study aimed to evaluate the cyclic fatigue resistance of two single file engine-driven instruments, Reciproc and NeoNiTi, in simulated root canals. Methods and Materials: Two groups of 15 NiTi endodontic instruments with an identical tip size of 0.25 mm were tested: Reciproc R25 (group A) and NeoNiTi A1 (group B). Cyclic fatigue testing was performed in a stainless steel artificial canal. The simulated canals had a 60° angle and 5-mm radius curvature. The Reciproc instruments were operated using the preset program on torque control electric motor specific for the Reciproc instruments, while the NeoNiTi instruments were operated using the manufacturer recommendation. All instruments were rotated until fracture occurred, and the number of cycles to fracture (NCF) and the length of the fractured tip were recorded and registered. Means and standard deviations of NCF and fragment length were calculated for each system and data were subjected to Student’s t test (P<0.05). Results: A statistically significant difference (P<0.05) was noted between Reciproc and NeoNiTi instruments. NeoNiTi A1 instruments were associated with a significantly higher mean NCF as compared to Reciproc R25 instruments (833±176 vs. 318±87 NCF). There was no significant difference (P>0.05) in the mean length of the fractured fragments between the instruments. Conclusion: NeoNiTi instruments were associated with a significantly higher cyclic fatigue resistance than Reciproc instruments.Keywords: Cyclic Fatigue; NeoNiTi; Reciproc; Single-File System

Infância livre, memória e documentário

"Tempos de bairro" explora o desaparecimento de um hábito infantil que era comum em gerações anteriores. Baseado nas memórias de uma infância pessoal, o documentário mostra um período de outrora onde as brincadeiras de rua formavam a paisagem de um bairro. Como tal, ao longo deste trabalho faz-se a revisitação de um passado e relata-se a experiência de um lugar. Evocam-se memórias e questiona-se o desaparecimento dessa 'tradição' infantil. Numa outra dimensão, este projecto é desenvolvido envolta da memória onde há, primeiramente, uma abordagem pessoal sobre as memórias de uma infância e, de seguida, uma procura por alternativas ao uso de material de arquivo. Por este revelar-se insuficiente, expõem-se algumas estratégias de representação dentro e fora do documentário como forma de retratar um tempo passado e de envolver o espectador na história. Com este projecto e a realização deste documentário pretende-se que o espectador se identifique com a temática e que, posteriormente, reconheça o valor dos espaços exteriores como um meio de exploração e de conhecimento do mundo para a infância."Neighborhood's Times" explores the disappearance of a childhood's habit which was common among previous generations. Based on personnal childhood memories, this documentary shows a period where playing in the street was a normal portrait of a neighborhood. As such, throughout this work I revisit a past and report the experience of a place. Memories are evoked and after It questions the disappearance of this childhood 'tradition'. On another dimension, this project is developed around the memory where there is first an personnal approach about childhood memories and then a search for alternatives to the use of archival material. As this one was insufficient, some strategies of representation inside and outside the documentary film are shown in order to describe a past time and to involve the spectator into the story. Through this project and documentary, I intend that the spectator can involve and identify himself into the subject, recognizing afterwards the value of outdoor spaces benefits as a way of exploration and knowledge to a child's world

Acute lower Limb Ischemia Caused by Fungal Infective Atrial Thrombus: A Case Report

Introduction: Septic thromboemboli have two consequences, ischemic and infection. In this paper we discuss a case with acute lower limb ischemia caused by fungal infective atrial thrombus. The patient underwent an anticoagulant therapy. Case presentation:                 A 43-year-old female patient who suffered from valvular heart disease (history of mitral and tricuspid valve replacement) was referred to the vascular surgery department of Modarres hospital with acute left limb ischemia. She underwent a successful emergency surgical thrombectomy. The pathological report of thrombus demonstrated fungal infection.  Conclusion: After surgical thrombectomy to control the acute lower limb ischemia, antimicrobial treatment of septic emboli is necessary

Association Of Raised Serum Triglycerides With Incidence Of Pre-Eclampsia

Background: Pre-eclampsia, a serious multi-systemic pregnancy complication is estimated to occur in 5-10% of pregnancies worldwide. Objective: To determine the frequency of pre-eclampsia in pregnant females with hyper-triglyceridemia and to study its associations. Methodology: This Cross-sectional study was conducted at Gynecology Dept. Poly Clinic Hospital, Islamabad (March - Sept. 2022). Pregnant females of age 15-40 years, gestational age 13-20th weeks and singleton pregnancy were included. Known hypertensives, receiving lipid-lowering or anti-hypertensives, chronic kidney or liver disease, teenage pregnancies, primigravida, history of CVA, IHD, epilepsy or endocrine disorders were excluded. After the detailed clinical evaluation, fasting serum triglyceride levels were checked. A total of 225 cases with elevated serum triglycerides were finally selected and evaluated for the presence of pre-eclampsia by monitoring the blood pressure, cardiovascular, gynaecological examination and urine for the presence of proteinuria. Patients were followed till the development of pre-eclampsia or completion of pregnancy.  Results: Among 225 pregnant females with raised serum triglycerides, the mean age was 24.28+5.5 years. Pre-eclampsia was observed in 47(20.89%) of patients.  The Chi-square tests of association between pre-eclampsia and each of parity, residential status, and socio-economic status were insignificant while BMI and Gestational age were significant.  Conclusion: There is a high prevalence of pre-eclampsia in pregnant women with hypertriglyceridemia. Serum triglyceride levels may predict the women at risk for pre-eclampsia. The risk of preeclampsia in women with hyper-triglyceridemia is independent of parity, and socioeconomic or residential status. Hypertriglyceridemia may predispose to pre-eclampsia even at lower BMI levels. The development of hypertriglyceridemia in early gestation may be an additional risk factor. Early screening of women at risk may lead to better outcomes

COVID-19-Related Spontaneous Pneumomediastinum: An Atypical Manifestation

COVID-19 is has been an emerging healthcare challenge during the last months. Herein we explain two cases with spontaneous pneumomediastinum as an atypical manifestation of COVID-19 disease; these two patients had confirmed COVID-19, leading to spontaneous pneumodeiastimun as an atypical manifestation during the course of hospital stay, presenting by abrupt deterioration in O2 saturation and symptoms. Spontaneous pneumomediastinum should be considered as a potential reason for the disease exacerbation in patients without previous history of mechanical ventilation. &nbsp

Investigations towards incorporation of Eu3+ and Cm3+ during ZrO2 crystallization in aqueous solution

Nuclear energy provides a widely applied carbon-reduced energy source. Following operation, the spent nuclear fuel (SNF), containing a mixture of radiotoxic elements such as transuranics, needs to be safely disposed of. Safe storage of SNF in a deep geological repository (DGR) relies on multiple engineered and natural retention barriers to prevent environmental contamination. In this context, zirconia (ZrO2) formed on the SNF rod cladding, could be employed as an engineered barrier for immobilization of radionuclides via structural incorporation. This study investigates the incorporation of Eu3+ and Cm3+, representatives for trivalent transuranics, into zirconia by co-precipitation and crystallization in aqueous solution at 80 °C. Complementary structural and microstructural characterization has been carried out by powder X-ray diffraction (PXRD), spectrum imaging analysis based on energy-dispersive X-ray spectroscopy in scanning transmission electron microscopy mode (STEM-EDXS), and luminescence spectroscopy. The results reveal the association of the dopants with the zirconia particles and elucidate the presence of distinct bulk and superficially incorporated species. Hydrothermal aging for up to 460 days in alkaline media points to great stability of these incorporated species after initial crystallization, with no indication of phase segregation or release of Eu3+ and Cm3+ over time. These results suggest that zirconia would be a suitable technical retention barrier for mobilized trivalent actinides in a DGR

Effective Knowledge Transfer: Application of the Media Richness Theory

Nowadays, information and knowledge are easily transmitted through communication and media types. Knowledge transfer must be in a manner that best meets the organization's business needs. The knowledge transfer quality depends on communication, and communication media have different levels of capability in transmitting knowledge; Media selection is based on various factors such as specific media features and the message content nature. The current research has been done by the library method. The necessary data were gathered through the study of printed and electronic information resources available in libraries, on the Internet, and in national and international databases. One of the success factors in transferring tacit knowledge depends on the selection of the appropriate knowledge transfer mechanism and communication media. Tacit knowledge (the most important type of knowledge) can be captured, stored, or transmitted using a specific type of technology based on the media enrichment theory. The main assumption of media richness theory is that person's performance in a communication situation is the result of proper conformity between the communication media features and intended task attributes. According to the media richness theory (MRT), each channel has its advantages and disadvantages, and as a result, each can be more ideal than the others for different scenarios. In the knowledge-sharing process after determining the implicit levels of knowledge (high, medium, low) by experts, based on media richness theory, the most appropriate media for transferring this type of knowledge is selected to ensure effectiveness