Peran Guru Dan Peserta Didik Dalam Membentuk Komunikasi Keaktifan Belajar Kelas VIII SMP Negeri 18 Satu Atap Kelurahan Tanjung Merah Kecamatan Matuari Kota Bitung

Peran adalah proses dinamis kedudukan (status). Apabila seseorang melaksanakan hak dan kewajibannya sesuai dengan kedudukannya, dia menjalankan suatu peranan. Perbedaan antara kedudukan dengan peranan adalah untuk kepentingan ilmu pengetahuan. Keduannya tidak dapat dipisah-pisahkan karena yang satu tergantung pada yang lain dan sebaliknya. Komunikasi merupakan proses penyampaian pesan atau interaksi dari pengirim kepada penerima. dalam hal ini materi pelajaran, oleh komunikator (guru) kepada komunikan (peserta didik) bisa dicerna dengan optimal, sehingga tujuan pendidikan yang ingin dicapai bisa terwujud. Keaktifan Belajar adalah upaya peserta didik dalam mengembang potensi diri melalui proses belajar dengan penggunaan model pembelajaran. Penelitian ini menggunakan metode kualitatif dengan lokasi penelitian pada SMP Negeri 18 Satu Atap Bitung dan informan yang di wawancarai ada 1 Kepala Sekolah, 4 Guru dan 6 Peserta Didik. Teknik Pengumpulan Data yang digunakan yaitu observasi, wawancara, dan dokumentasi. Hasil dari penelitian menunjukan bahwa, jika 6 peserta didik merasa masih kesulitan berkomunikasi dengan guru selama dalam pembelajaran berlangsung, dan 4 guru juga merasa demikian menganggap bahwa yang menjadi kendala dalam berkomunikasi ketidakantusiasan kurangnya keterbukaan menjadi salah satu kendala dan kurang percaya diri dari peserta didik, dan kurangnya kenyamanan di kelas dapat menjadi alasan peserta didik menjadi pasif atau kurang berkomunikasi. Kata Kunci : Peran, Guru, Peserta Didik, Komunikasi, Keaktifan Belaja

The use and benefits of computer mediated learning in teaching biology

Of increasing concern among higher education institutions is the problem of maintaining the quality of education in the face of increased student numbers and continuing funding cuts. These concerns, coupled with the advent of readily accessible and relatively cost effective computer technology, has seen a marked increase in the use of computer-based education delivery systems in universities. Much debate now centres on how effective and beneficial computer-based learning (CBL) is, particularly with respect to learning and cognitive processes (Brown et al. 1989; Rowe 1993), student performance (Mevarech et al. 1991; Stewell and Delpierre 1992; Blackmore and Britt 1993; Mevarech 1993; Chambers et al. 1995), gender and age related performance (Massoud 1991; Lee 1993; Colley et al. 1994; Dyck and Smither 1994) and software design and mode of delivery (Ahern 1993; Jackson et al. 1993; Rowe 1993; Chambers et al. 1995). Addressing these questions is difficult due to a lack of published data and because comparisons of student performance are difficult given the highly diverse ways in which CBL is approached, implemented and evaluated. One area to which CBL readily lends itself is the use of computer simulations in practical or laboratory teaching. Laboratory classes aim to teach students principles of experimental design, data collection, data processing as well as the correct usage of commonly used laboratory equipment. The application of computer simulations can be beneficial if (i) the costs of running a particular experiment are prohibitive (ii) time constraints apply e.g., growth or breeding experiments (iii) ethical or humane considerations are involved e.g., experiments involving euthanasia of large numbers of animals (iv) it is difficult to observe or manipulate the phenomenon under consideration e.g., nutrient cycling in a plant community (v) it is important that students are familiar with a piece of equipment or procedure prior to undertaking an experiment e.g., familiarity with the use of a spectrophotometer (vi) rapid and efficient feedback on a students understanding of the subject material is desirable (vii) the experiments are technically demanding (ix) require the use of dangerous or radioactive compounds. This talk will be primarily on the use of computer simulations in biology but I will talk about laboratory marking programs and tutorial assessment programs

Nonlinear aspects of the EEG during sleep in children

Electroencephalograph (EEG) analysis enables the neuronal behavior of a section of the brain to be examined. If the behavior is nonlinear then nonlinear tools can be used to glean information on brain behavior, and aid in the diagnosis of sleep abnormalities such as obstructive sleep apnea syndrome (OSAS). In this paper the sleep EEGs of a set of normal and mild OSAS children are evaluated for nonlinear behaviour. We consider how the behaviour of the brain changes with sleep stage and between normal and OSAS children.Comment: 9 pages, 2 figures, 4 table

Effects of designed PLLA and 50:50 PLGA scaffold architectures on bone formation in vivo

Biodegradable porous scaffolds have been investigated as an alternative approach to current metal, ceramic, and polymer bone graft substitutes for lost or damaged bone tissues. Although there have been many studies investigating the effects of scaffold architecture on bone formation, many of these scaffolds were fabricated using conventional methods such as salt leaching and phase separation, and were constructed without designed architecture. To study the effects of both designed architecture and material on bone formation, this study designed and fabricated three types of porous scaffold architecture from two biodegradable materials, poly (L‐lactic acid) (PLLA) and 50:50 Poly(lactic‐co‐glycolic acid) (PLGA), using image based design and indirect solid freeform fabrication techniques, seeded them with bone morphogenetic protein‐7 transduced human gingival fibroblasts, and implanted them subcutaneously into mice for 4 and 8 weeks. Micro‐computed tomography data confirmed that the fabricated porous scaffolds replicated the designed architectures. Histological analysis revealed that the 50:50 PLGA scaffolds degraded but did not maintain their architecture after 4 weeks implantation. However, PLLA scaffolds maintained their architecture at both time points and showed improved bone ingrowth, which followed the internal architecture of the scaffolds. Mechanical properties of both PLLA and 50:50 PLGA scaffolds decreased but PLLA scaffolds maintained greater mechanical properties than 50:50 PLGA after implantation. The increase of mineralized tissue helped support the mechanical properties of bone tissue and scaffold constructs between 4–8 weeks. The results indicate the importance of choice of scaffold materials and computationally designed scaffolds to control tissue formation and mechanical properties for desired bone tissue regeneration. Copyright © 2011 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96424/1/term497.pd

Degradation, Bioactivity, and Osteogenic Potential of Composites Made of PLGA and Two Different Sol–Gel Bioactive Glasses

We have developed poly(l-lactide-co-glycolide) (PLGA) based composites using sol–gel derived bioactive glasses (S-BG), previously described by our group, as composite components. Two different composite types were manufactured that contained either S2—high content silica S-BG, or A2—high content lime S-BG. The composites were evaluated in the form of sheets and 3D scaffolds. Sheets containing 12, 21, and 33 vol.% of each bioactive glass were characterized for mechanical properties, wettability, hydrolytic degradation, and surface bioactivity. Sheets containing A2 S-BG rapidly formed a hydroxyapatite surface layer after incubation in simulated body fluid. The incorporation of either S-BG increased the tensile strength and Young’s modulus of the composites and tailored their degradation rates compared to starting compounds. Sheets and 3D scaffolds were evaluated for their ability to support growth of human bone marrow cells (BMC) and MG-63 cells, respectively. Cells were grown in non-differentiating, osteogenic or osteoclast-inducing conditions. Osteogenesis was induced with either recombinant human BMP-2 or dexamethasone, and osteoclast formation with M-CSF. BMC viability was lower at higher S-BG content, though specific ALP/cell was significantly higher on PLGA/A2-33 composites. Composites containing S2 S-BG enhanced calcification of extracellular matrix by BMC, whereas incorporation of A2 S-BG in the composites promoted osteoclast formation from BMC. MG-63 osteoblast-like cells seeded in porous scaffolds containing S2 maintained viability and secreted collagen and calcium throughout the scaffolds. Overall, the presented data show functional versatility of the composites studied and indicate their potential to design a wide variety of implant materials differing in physico-chemical properties and biological applications. We propose these sol–gel derived bioactive glass–PLGA composites may prove excellent potential orthopedic and dental biomaterials supporting bone formation and remodeling

Adenotonsillectomy and neurocognitive deficits in children with sleep disordered breathing

Copyright: © 2009 Kohler et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Sleep Disordered Breathing (SDB) is a common childhood disorder that encompasses a range of sleep-related upper airway obstruction. Children with SDB demonstrate significant neurocognitive deficits. Adenotonsillectomy is the first line of treatment for SDB and whilst this improves respiratory disturbance, it remains to be established whether neurocognitive gains also result. Methods: A total of 44 healthy snoring children aged 3–12 years awaiting adenotonsillectomy (SDB group), and 48 age and gender matched non-snoring controls from the general community, completed the study. All children underwent polysomnography and neurocognitive assessment at baseline and after a 6-month follow-up (after surgery in the snoring group). Our primary aim was to determine whether neurocognitive deficits in snoring children were significantly improved following adenotonsillectomy. Results: Wide ranging neurocognitive deficits were found at baseline in SDB children compared to controls, most notably a 10 point IQ difference (P<.001) and similar deficits in language and executive function. Whilst adenotonsillectomy improved respiratory parameters and snoring frequency at 6 months post surgery, neurocognitive performance did not improve relative to controls. Conclusion: Adenotonsillectomy successfully treated the respiratory effects of SDB in children. However, neurocognitive deficits did not improve 6-months post-operativelyMark J. Kohler, Kurt Lushington, Cameron J. van den Heuvel, James Martin, Yvonne Pamula and Declan Kenned

The inconsistent nature of heart rate variability during sleep in normal children and adolescents

Introduction: Cardiac function is modulated by multiple factors including exogenous (circadian rhythm) and endogenous (ultradian 90-110 min sleep cycle) factors. By evaluating heart rate variability (HRV) during sleep, we will better understand their influence on cardiac activity. The aim of this study was to evaluate HRV in the dark phase of the circadian rhythm during sleep in healthy children and adolescents. Methods: One 3 min segment of pre-sleep electrocardiography (EEG) and 3, 6 min segments of electrocardiography recorded during polysomnography from 75 healthy children and adolescents were sampled during progressive cycles of slow wave sleep (SWS1, SWS2, SWS3). Three, 3 min segments of rapid eye movement sleep (REM) were also assessed, with REM1 marked at the last REM period before awakening. Studies that recorded REM3 prior to SWS3 were used for assessment. HRV variables include the following time domain values: mean NN (average RR intervals over given time), SDNN (Standard Deviation of RR intervals), and RMSSD (root Mean Square of beat-to-beat Differences). Frequency domain values include: low frequency (LF), high frequency (HF), and LF:HF. Results: Mixed linear effects model analysis revealed a significant difference in time and frequency domain values between sleep cycles and stages. Mean NN was lowest (highest heart rate) during pre-sleep then significantly increased across SWS1-3. Mean NN in SWS1 was similar to all REM periods which was significantly lower than both SWS2 and SWS3. SDNN remained at pre-sleep levels until SWS3, and then significantly increased in REM1&2. There was a large drop in LF from pre-sleep to SWS1. As cycles progressed through the night, LF remains lower than awake but increases to awake like levels by REM2. RMSSD and HF were lowest in pre-sleep and increased significantly by SWS1 and remain high and stable across stages and cycles except during the REM3 period where RMSSD decreased. Conclusion: Our results demonstrate that there are considerable changes in the spectral analysis of cardiac function occurring during different sleep stages and between sleep cycles across the night. Hence, time of night and sleep stage need to be considered when reporting any HRV differences.Anna Kontos, Mathias Baumert, Kurt Lushington, Declan Kennedy, Mark Kohler, Diana Cicua-Navarro, Yvonne Pamula, and James Marti

An Attack Graph-Based Probabilistic Security Metric

Abstract. To protect critical resources in today’s networked environments, it is desirable to quantify the likelihood of potential multi-step attacks that combine multiple vulnerabilities. This now becomes feasible due to a model of causal re-lationships between vulnerabilities, namely, attack graph. This paper proposes an attack graph-based probabilistic metric for network security and studies its effi-cient computation. We first define the basic metric and provide an intuitive and meaningful interpretation to the metric. We then study the definition in more com-plex attack graphs with cycles and extend the definition accordingly. We show that computing the metric directly from its definition is not efficient in many cases and propose heuristics to improve the efficiency of such computation.

Lower extremity robotic exoskeleton devices for overground ambulation recovery in acquired brain injury—A review

Acquired brain injury (ABI) is a leading cause of ambulation deficits in the United States every year. ABI (stroke, traumatic brain injury and cerebral palsy) results in ambulation deficits with residual gait and balance deviations persisting even after 1 year. Current research is focused on evaluating the effect of robotic exoskeleton devices (RD) for overground gait and balance training. In order to understand the device effectiveness on neuroplasticity, it is important to understand RD effectiveness in the context of both downstream (functional, biomechanical and physiological) and upstream (cortical) metrics. The review identifies gaps in research areas and suggests recommendations for future research. We carefully delineate between the preliminary studies and randomized clinical trials in the interpretation of existing evidence. We present a comprehensive review of the clinical and pre-clinical research that evaluated therapeutic effects of RDs using various domains, diagnosis and stage of recovery

Ultrafast structural changes direct the first molecular events of vision

視覚に関わるタンパク質の超高速分子動画 --薄暗いところで光を感じる仕組み--. 京都大学プレスリリース. 2023-03-23.Vision is initiated by the rhodopsin family of light-sensitive G protein-coupled receptors (GPCRs). A photon is absorbed by the 11-cis retinal chromophore of rhodopsin, which isomerizes within 200 femtoseconds to the all-trans conformation, thereby initiating the cellular signal transduction processes that ultimately lead to vision. However, the intramolecular mechanism by which the photoactivated retinal induces the activation events inside rhodopsin remains experimentally unclear. Here we use ultrafast time-resolved crystallography at room temperature to determine how an isomerized twisted all-trans retinal stores the photon energy that is required to initiate the protein conformational changes associated with the formation of the G protein-binding signalling state. The distorted retinal at a 1-ps time delay after photoactivation has pulled away from half of its numerous interactions with its binding pocket, and the excess of the photon energy is released through an anisotropic protein breathing motion in the direction of the extracellular space. Notably, the very early structural motions in the protein side chains of rhodopsin appear in regions that are involved in later stages of the conserved class A GPCR activation mechanism. Our study sheds light on the earliest stages of vision in vertebrates and points to fundamental aspects of the molecular mechanisms of agonist-mediated GPCR activation