Evolution and development of Brain Networks: From Caenorhabditis elegans to Homo sapiens

Neural networks show a progressive increase in complexity during the time course of evolution. From diffuse nerve nets in Cnidaria to modular, hierarchical systems in macaque and humans, there is a gradual shift from simple processes involving a limited amount of tasks and modalities to complex functional and behavioral processing integrating different kinds of information from highly specialized tissue. However, studies in a range of species suggest that fundamental similarities, in spatial and topological features as well as in developmental mechanisms for network formation, are retained across evolution. 'Small-world' topology and highly connected regions (hubs) are prevalent across the evolutionary scale, ensuring efficient processing and resilience to internal (e.g. lesions) and external (e.g. environment) changes. Furthermore, in most species, even the establishment of hubs, long-range connections linking distant components, and a modular organization, relies on similar mechanisms. In conclusion, evolutionary divergence leads to greater complexity while following essential developmental constraints

Built-in-self-test and foreground calibration of SAR ADCs

This thesis explores the scope of ‘Built-in-Self-Test’(BIST) schemes to reduce the time cost complexity associated with the production tests for static linearity errors in Successive Approximation (SAR) ADCs. In this regard, an on-chip implementation of the ‘Stimulus Based Error Identification and Removal’ (SEIR) method [1] is sought to be pursued. As an extension, it is proposed that the estimated ADC non-linearities may then be suitably calibrated to achieve higher resolution. A brief review of the testing and calibration algorithm is undertaken. Further, this work elaborates on the design of a prototype front-end test generator and a buffer interface to calibrate a 10MHz 14 bit redundant SAR ADC in the TSMC 180nm process. Simulation results validating the circuit implementation of the integrated front-end system have been presented.Electrical and Computer Engineerin

PENGARUH DOSIS KUNING TELUR TERHADAP DAYA TAHAN HIDUP SPERMATOZOA AYAM KAMPUNG (GALLUS DOMESTICUS) DALAM PENGENCER NACL FISIOLOGIS

Banda Ace

DOSE-DEPENDENT CHRONIC TOXICITY SCREENING OF HINOKITIOL IN ZEBRAFISHES: BEHAVIORAL AND HISTOLOGICAL APPROACH

Objectives: Parkinson’s disease (PD) is categorized as a movement disorder symptomized by weakening the motor skills of the patients. The root cause of the disease is the neurodegenerative dopaminergic loss in the substantia nigra of the patient’s brain. This havoc disease majorly affects the people above the age of 60 years. Moreover, PD incidences strike almost 70% of the neurological disorders of the aged population worldwide. There are no perfect curative drugs in the medical world for the disease. Since the past few decades, several plant secondary compounds were in preclinical trials to treat this disease. Hinokitiol (HIN), a monoterpenoid from the heartwood of cupressaceous plants, is widely used in hair tonics, toothpaste, cosmetics, and food as an antimicrobial agent. It is well reported as an anti-stroke agent as well. Methods: In the present study, the dose-dependent (5, 10, 15, 20, and 25 mg/kg) chronic toxicity of HIN was studied for 28 days using zebrafishes. The toxicity was analyzed in vital organs such as brain, liver, kidney, spleen, heart, and blood count followed by behavioral toxicity to target the drug against parkinsonism. Results: The study revealed that the higher doses of 20 and 25 mg/kg HIN treatment were toxic to the fish brain, spleen, as well as cardiomyocytes. It showed a variation in blood count as well at 10 mg/kg dose itself. Conclusion: Hence, the study revealed the protective efficacy of the HIN at its therapeutic dosage of 5 mg/kg as a neuroprotective drug, with minimal vital organ toxicities

Unpacking instructional alignment: The influence of teachers’ use of assessment data on instruction

The use of assessment data to inform instruction is an important component of a comprehensive standards-based assessment programme. Examining teachers’ data use for instruction can reveal the extent to which instruction is aligned with established content standards and assessment. This paper describes results of a qualitative study of teachers’ data use in a mid-Atlantic metropolitan area in the United States. Focus group interviews with 60 upper elementary and middle school teachers from 45 schools were conducted. Findings indicate teachers aligned instruction and assessments with the state curriculum with the goal of improving student performance. While teachers found day-to-day informal assessments essential to shaping instruction, periodic formal assessments helped them monitor student progress and remediation efforts. Teachers described challenges associated with the misalignment of periodic assessments with instructional content, the breadth of content and higher cognitive demand expected in the newer state curriculum and the lack of infrastructure to support data use

Establishing, versus Maintaining, Brain Function: A Neuro-computational Model of Cortical Reorganization after Injury to the Immature Brain

The effect of age at injury on outcome after acquired brain injury (ABI) has been the subject of much debate. Many argue that young brains are relatively tolerant of injury. A contrasting viewpoint due to Hebb argues that greater system integrity may be required for the initial establishment of a function than for preservation of an already-established function. A neuro-computational model of cortical map formation was adapted to examine effects of focal and distributed injury at various stages of development. This neural network model requires a period of training during which it self-organizes to establish cortical maps. Injuries were simulated by lesioning the model at various stages of this process and network function was monitored as "development" progressed to completion. Lesion effects are greater for larger, earlier, and distributed (multifocal) lesions. The mature system is relatively robust, particularly to focal injury. Activities in recovering systems injured at an early stage show changes that emerge after an asymptomatic interval. Early injuries cause qualitative changes in system behavior that emerge after a delay during which the effects of the injury are latent. Functions that are incompletely established at the time of injury may be vulnerable particularly to multifocal injury

Formative Assessment and Benchmark Testing: Phase 2

As school districts respond to test-based accountability requirements the emphasis on using data to drive decision making has most recently focused on using interim or benchmark assessment results. The use of these assessments to monitor student progress and inform instruction with the aim to improve learning is widespread. When considered in a continuum of assessments based on the proximity to instruction, benchmark assessments are located between teachers’ minute-by-minute and daily formative assessment practices that are used to direct instruction to support learning, and the summative unit assessments, or tests administered after instruction has occurred to measure learning. As such, the intended purpose of benchmark assessments blends the ideas of data-driven decision making with the principles of formative assessment. The expectation is that school administrators and teachers will use these test results to identify students’ misunderstandings and correct the course of learning in preparation for the year-end state mandated exams. Examining the extent to which benchmark assessments results are being used in this formative way was the primary aim of this study. This report presents results of a survey of elementary and middle school teachers in four school divisions about their use of benchmark assessment data to improve instruction and support student learning. This report documents the second phase of a two-stage investigation of teachers’ formative uses of benchmark assessment results.