5,540 research outputs found

    Peningkatan Minat Belajar Ipa Melalui Strategi Make A Match Yang Dimodifikasi Pada Siswa Kelas V SDN 1 Kedunglengkong Simo Boyolali Tahun 2013/2014

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    Penelitian ini bertujuan untuk meningkatkan minat belajar IPA melalui strategi Make a Match yang dimodifikasi pada siswa kelas V SDN 1 Kedunglengkong Simo Boyolali. Penelitian adalah penelitian tindakan kelas, dengan Subyek penelitian guru dan siswa kelas V SDN 1 Kedunglengkong sejumlah 25 siswa dan mata pelajaran IPA sebagai objek. Metode pengumpulan data yaitu observasi, tes, wawancara dan dokumentasi. Analisis data menggunakan analisis interaktif yang terdiri dari proses reduksi, beberan data dan kesimpulan. Hasil penelitian menunjukkan peningkatan minat belajar IPA yang berdampak pada peningkatan hasil belajar siswa. Indikator minat : Rasa Suka dalam mengikuti pembelajaran pada pra siklus sebanyak 4 siswa (16%), siklus I pertemuan I ada 9 siswa (39,1%), siklus I pertemuan II ada 14 siswa (66,7%), siklus II pertemuan I ada 21 siswa (84%), dan siklus II pertemuan II ada 20 siswa (86,9%). Perhatian siswa saat pembelajaran pada pra siklus sebanyak 9 siswa (36%), siklus I pertemuan I ada 13 siswa (56,5%), siklus I pertemuan II ada 17 siswa (80,9%), siklus II pertemuan I ada 20 siswa (80%), dan siklus II pertemuan II ada 21 siswa (91,3%). Partisipasi siswa saat pembelajaran berlangsung pada pra siklus sebanyak 6 siswa (24%), siklus I pertemuan I ada 10 siswa (43%), siklus I pertemuan II ada 10 siswa (47,6%), siklus II pertemuan I ada 18 siswa (72%), dan siklus II pertemuan II ada 19 siswa (82,6%). Hasil belajar siswa sebelum perlakuan yang mencapai nilai tuntas ≥KKM (60) ada 8 siswa (32%), dan pada siklus I pertemuan I ada 13 siswa (56,5%), pada siklus I pertemuan II ada 14 siswa (66,7%) dan pada siklus II pertemuan I ada 19 siswa (76%) dan pada siklus II pertemuan II ada 19 siswa (82,6%). Kesimpulan penelitian ini adalah penerapan strategi pembelajaran Make a Match dapat meningkatkan minat belajar IPA siswa kelas V SDN 1 Kedunglengkong Simo Boyolali tahun 2013/2014

    Osteology of the Late Cretaceous Argentinean sauropod dinosaur Mendozasaurus neguyelap: implications for basal titanosaur relationships

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    The titanosaurian sauropod dinosaur Mendozasaurus neguyelap is represented by several partial skeletons from a single locality within the Coniacian (lower Upper Cretaceous) Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina. A detailed revision of Mendozasaurus, including previously undocumented remains from the holotype site, allows us to more firmly establish its position within Titanosauria, as well as enabling an emended diagnosis of this taxon. Autapomorphies include: (1) middle and posterior cervical vertebrae with tall and transversely expanded neural spines that are wider than the centra, formed laterally by spinodiapophyseal laminae that are not connected with the pre- or postzygapophyses; (2) anterior caudal vertebrae (excluding anteriormost) with ventrolateral ridge-like expansion of prezygapophyses; and (3) humerus with divided lateral distal condyle on anterior surface. New remains demonstrate that the presacral vertebrae of Mendozasaurus were not unusually short anteroposteriorly, with this compression instead resulting from taphonomic crushing. Comparative studies of articulated pedes of other taxa allow us to interpret that the pedal formula of Mendozasaurus was 2-2-2-2-0, based on disarticulated bones that form a right hind foot. Mendozasaurus was incorporated into an expanded version of a titanosauriform-focussed phylogenetic data matrix, along with several other contemporaneous South American titanosaurs. The resultant data matrix comprises 84 taxa scored for 423 characters, and our phylogenetic analysis recovers Mendozasaurus as the most basal member of a diverse Lognkosauria, including Futalognkosaurus and the gigantic titanosaurs Argentinosaurus, Notocolossus, Patagotitan and Puertasaurus. Lognkosauria forms a clade with Rinconsauria (Muyelensaurus + Rinconsaurus), with Epachthosaurus and Pitekunsaurus recovered at the base of this grouping. A basal lithostrotian position for this South American clade is well supported, contrasting with some analyses that have placed these taxa outside of Lithostrotia or closer to Saltasauridae. The sister clade to this South American group is composed of an array of near-global taxa and supports the hypothesis that most titanosaurian clades were widespread by the Early–middle Cretaceous

    An Investigation of Racing Performance and Whip Use by Jockeys in Thoroughbred Races

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    Concerns have been expressed concerning animal-welfare issues associated with whip use during Thoroughbred races. However, there have been no studies of relationships between performance and use of whips in Thoroughbred racing. Our aim was to describe whip use and the horses' performance during races, and to investigate associations between whip use and racing performance. Under the Australian Racing Board (ARB) rules, only horses that are in contention can be whipped, so we expected that whippings would be associated with superior performance, and those superior performances would be explained by an effect of whipping on horse velocities in the final 400 m of the race. We were also interested to determine whether performance in the latter sections of a race was associated with performance in the earlier sections of a race. Measurements of whip strikes and sectional times during each of the final three 200 metre (m) sections of five races were analysed. Jockeys in more advanced placings at the final 400 and 200 m positions in the races whipped their horses more frequently. Horses, on average, achieved highest speeds in the 600 to 400 m section when there was no whip use, and the increased whip use was most frequent in the final two 200 m sections when horses were fatigued. This increased whip use was not associated with significant variation in velocity as a predictor of superior placing at the finish

    Comparison of quantitative real time PCR with Sequencing and ribosomal RNA-FISH for the identification of fungi in Formalin fixed, paraffin-embedded tissue specimens

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    Background: Identification of the causative agents of invasive fungal infections (IFI) is critical for guiding antifungal therapy. Cultures remain negative in a substantial number of IFI cases. Accordingly, species identification from formalin fixed, paraffin embedded (FFPE) tissue specimens by molecular methods such as fluorescence in situ hybridisation (FISH) and PCR provides an appealing approach to improve management of patients. Methods: We designed FISH probes targeting the 28S rRNA of Aspergillus and Candida and evaluated them with type strains. Fluorescence microscopy (FM), using FISH probes and quantitative broadrange fungal PCR targeting the rRNA gene were applied to FFPE tissue specimens from patients with proven IFI in order to explore benefits and limitations of each approach. Results: PCR followed by sequencing identified a broad spectrum of pathogenic fungi in 28 of 40 evaluable samples (70%). Hybridisation of FISH probes to fungal rRNA was documented in 19 of 40 tissue samples (47.5%), including 3 PCR negative samples with low fungal burden. The use of FISH was highly sensitive in invasive yeast infections, but less sensitive for moulds. In samples with hyphal elements, the evaluation of hybridisation was impaired due to autofluorescence of hyphae and necrotic tissue background. Conclusions: While PCR appears to be more sensitive in identifying the causative agents of IFI, some PCR negative and FISH positive samples suggest that FISH has some potential in the rapid identification of fungi from FFPE tissue samples

    CD40L is selectively expressed on platelets from thrombocytopenic septic patients

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    Introduction It has been recently hypothesized that septic microangio- pathy is caused or at least promoted by the interaction between endo- thelial surface receptor CD40 and its ligand CD40L, expressed by activated platelets. This interaction produces procoagulative changes in endothelial cells, endothelial apoptosis, subendothelial matrix exposition and microthrombi formation. Since virtually all septic patients show a certain degree of coagulation abnormalities, we hypothesized that low platelet count is associated with a diff erent degree of CD40L expression and that this could correlate with the severity of disease. Methods To determine the infl uence of sepsis on levels of platelet-derived CD40L expression, we performed a prospective observational study in a polyvalent university hospital ICU. Eighteen consecutively septic patients were enrolled in the study, independently of the platelet count and the severity of disease (SOFA score). Flow cytometry of fresh blood from septic patients (n = 18) and age-matched controls (n = 8) was performed for membrane-bound CD40L and CD62P on circulating platelets. Results Flow cytometry demonstrated low levels of CD62P in controls while the levels in patients were high. CD40L+ platelets were selectively found from patients with thrombocytopenia (platelet count ≤60,000/mm3). Furthermore a direct correlation between CD40L expression and the SOFA score was found in patients with sepsis and thrombocytopenia compared to patients with sepsis without thrombocytopenia. Conclusions These results suggest that CD40L expression on platelets is somehow related to the degree of thrombocytopenia and possibly can be a marker of the severity of sepsis. Although the role of endothelial- derived CD40/platelet-derived CD40L interaction is not fully understood during sepsis, the expression of CD40L on platelets could be related to the severity of organ disease due to the possible bursting of endothelial damage through this pathway. Further investigation is needed to determine whether platelets CD40L contributes to endothelial and subsequent organ damage, its role in thrombocytopenia and its correlation with the outcome of sepsis. The microvascular injury seems to be a central event in sepsis, so understanding the mechanisms underlying its development is crucial for the individuation of new and specifi c therapeutic strategies

    Gene conversion in human rearranged immunoglobulin genes

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    Over the past 20 years, many DNA sequences have been published suggesting that all or part of the V<sub>H</sub> segment of a rearranged immunoglobulin gene may be replaced in vivo. Two different mechanisms appear to be operating. One of these is very similar to primary V(D)J recombination, involving the RAG proteins acting upon recombination signal sequences, and this has recently been proven to occur. Other sequences, many of which show partial V<sub>H</sub> replacements with no addition of untemplated nucleotides at the V<sub>H</sub>–V<sub>H</sub> joint, have been proposed to occur by an unusual RAG-mediated recombination with the formation of hybrid (coding-to-signal) joints. These appear to occur in cells already undergoing somatic hypermutation in which, some authors are convinced, RAG genes are silenced. We recently proposed that the latter type of V<sub>H</sub> replacement might occur by homologous recombination initiated by the activity of AID (activation-induced cytidine deaminase), which is essential for somatic hypermutation and gene conversion. The latter has been observed in other species, but not in human Ig genes, so far. In this paper, we present a new analysis of sequences published as examples of the second type of rearrangement. This not only shows that AID recognition motifs occur in recombination regions but also that some sequences show replacement of central sections by a sequence from another gene, similar to gene conversion in the immunoglobulin genes of other species. These observations support the proposal that this type of rearrangement is likely to be AID-mediated rather than RAG-mediated and is consistent with gene conversion

    Study protocol: a randomised controlled trial investigating the effect of exercise training on peripheral blood gene expression in patients with stable angina

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    Background: Exercise training has been shown to reduce angina and promote collateral vessel development in patients with coronary artery disease. However, the mechanism whereby exercise exerts these beneficial effects is unclear. There has been increasing interest in the use of whole genome peripheral blood gene expression in a wide range of conditions to attempt to identify both novel mechanisms of disease and transcriptional biomarkers. This protocol describes a study in which we will assess the effect of a structured exercise programme on peripheral blood gene expression in patients with stable angina, and correlate this with changes in angina level, anxiety, depression, and exercise capacity. Methods/Design: Sixty patients with stable angina will be recruited and randomised 1: 1 to exercise training or conventional care. Patients randomised to exercise training will attend an exercise physiology laboratory up to three times weekly for supervised aerobic interval training sessions of one hour in total duration. Patients will undergo assessments of angina, anxiety, depression, and peripheral blood gene expression at baseline, after six and twelve weeks of training, and twelve weeks after formal exercise training ceases. Discussion: This study will provide comprehensive data on the effect of exercise training on peripheral blood gene expression in patients with angina. By correlating this with improvement in angina status we will identify candidate peripheral blood transcriptional markers predictive of improvements in angina level in response to exercise training

    Cognitive decline and quality of life in incident Parkinson's disease: The role of attention.

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    INTRODUCTION: Parkinson's disease dementia (PDD) is associated with poorer quality of life (QoL). Prior to the onset of PDD, many patients experience progressive cognitive impairment. There is a paucity of longitudinal studies investigating the effects of cognitive decline on QoL. This study aimed to determine the longitudinal impact of cognitive change on QoL in an incident PD cohort. METHODS: Recently diagnosed patients with PD (n = 212) completed a schedule of neuropsychological assessments and QoL measures; these were repeated after 18 (n = 190) and 36 months (n = 158). Mild cognitive impairment (PD-MCI) was classified with reference to the Movement Disorder Society criteria. Principal component analysis was used to reduce 10 neuropsychological tests to three cognitive factors: attention, memory/executive function, and global cognition. RESULTS: Baseline PD-MCI was a significant contributor to QoL (β = 0.2, p < 0.01). For those subjects (9%) who developed dementia, cognitive function had a much greater impact on QoL (β = 10.3, p < 0.05). Multivariate modelling showed attentional deficits had the strongest predictive power (β = -2.3, p < 0.01); brief global tests only modestly predicted decline in QoL (β = -0.4, p < 0.01). CONCLUSIONS: PD-MCI was associated with poorer QoL over three years follow up. Cognitive impairment had a greater impact on QoL in individuals who developed dementia over follow-up. Impaired attention was a significant determinant of QoL in PD. Interventions which improve concentration and attention in those with PD could potentially improve QoL

    Non-lethal control of the cariogenic potential of an agent-based model for dental plaque

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    Dental caries or tooth decay is a prevalent global disease whose causative agent is the oral biofilm known as plaque. According to the ecological plaque hypothesis, this biofilm becomes pathogenic when external challenges drive it towards a state with a high proportion of acid-producing bacteria. Determining which factors control biofilm composition is therefore desirable when developing novel clinical treatments to combat caries, but is also challenging due to the system complexity and the existence of multiple bacterial species performing similar functions. Here we employ agent-based mathematical modelling to simulate a biofilm consisting of two competing, distinct types of bacterial populations, each parameterised by their nutrient uptake and aciduricity, periodically subjected to an acid challenge resulting from the metabolism of dietary carbohydrates. It was found that one population was progressively eliminated from the system to give either a benign or a pathogenic biofilm, with a tipping point between these two fates depending on a multiplicity of factors relating to microbial physiology and biofilm geometry. Parameter sensitivity was quantified by individually varying the model parameters against putative experimental measures, suggesting non-lethal interventions that can favourably modulate biofilm composition. We discuss how the same parameter sensitivity data can be used to guide the design of validation experiments, and argue for the benefits of in silico modelling in providing an additional predictive capability upstream from in vitro experiments
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