500 research outputs found

    Influence of barium on rectification in rat neocortical neurons

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    The effect of low concentrations of barium on the membrane properties of rat neocortical neurons was studied in vitro. Potassium currents were examined using single-electrode current- and voltage-clamp techniques. Neurons responded to bath application of barium (10–100 μM) with a membrane depolarization associated with an increase in input resistance. Under voltage clamp conditions, an inward shift in holding current was observed. The effects of barium were rapidly reversible upon washing and persisted in the presence of TTX. The equilibrium potential for the barium-induced inward current was near −110 mV, suggesting that barium inhibited a tonically active potassium conductance. Measurements of current voltage relationships indicated an inward rectification of this conductance between −50 and −130 mV. These results provide strong evidence that barium blocks a persistent potassium ‘leak’ current in neocortical neurons that contributes to the resting potential of these cells

    On the existence, uniqueness and parametric dependence on the coefficients of the solution processes in McShane's stochastic integral equations

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    In this paper we use the Schauder fixed point theorem and methods of integral inequalities in order to prove a result on the existence, uniqueness and parametric dependence on the coefficients of the solution processes in McShane stochastic integral equations

    Relative brain size is associated with natal dispersal rate and species' vulnerability to climate change in seabirds

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    The cognitive buffer hypothesis proposes that species with larger brains (relative to their body size) exhibit greater behavioural flexibility, conferring an advantage in unpredictable or novel environments. Therefore, behavioural flexibility – and relative brain size – are likely to be important predictors of a species' vulnerability to anthropogenic pressures and, ultimately, extinction risk. However, current evidence linking brain size to species' vulnerability and extinction risk is inconclusive. Furthermore, studies examining the relationship between relative brain size and behavioural flexibility have mainly focused on foraging innovations, whilst other forms of behavioural flexibility remain unexplored. In this study, we collate species-specific information and examine links between relative brain size, rates of natal and adult dispersal (a measure of flexibility in breeding site fidelity), vulnerability to six anthropogenic threats and extinction risk for 131 species of seabird. We focused our study on seabirds, a highly threatened group that displays large variation in both relative brain size and dispersal behaviour. We found a significant positive relationship between relative brain size and natal dispersal rate, suggesting that relative brain size could enhance flexibility in breeding site choice in seabirds, consistent with the cognitive buffer hypothesis. However, this relationship does not persist when we consider adult dispersal, possibly reflecting constraints imposed by mate selection and knowledge transfer in seabirds. We also show that relative brain size is negatively associated with vulnerability to climate change. These findings have immediate application for predicting interspecific variation in species' vulnerability to climate change and identifying priority species for conservation

    STUDI EVALUASI KINERJA SIMPANG BERSINYAL JALAN RANU GRATI – JALAN DANAU TOBA KOTA MALANG

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    Kebutuhan transportasi akan terus meningkat dengan berkembangnya daerah perkotaan. Jika kebutuhan sarana transportasi tidak diimbangin dengan prasarana (jaringan jalan) maka timbul masalah transportasi. Kondisi ini terjadi pada ruas Jl. Ranu Grati – Jl. Danau Toba Kota Malang, dimana jumlah volume tidak seimbang dengan kapasitas jalan dan persimpangan sehingga timbulnya penumpukan arus lalu lintas serta membuat antrian sangat panjang sehingga menyebabkan kemacetan pada jam sibuk dan terjadinya tundaan dan antrian panjang. Tujuan dari studi adalah untuk mencari alternatif pemecahan masalah yang sesuai dengan permasalahan tersebut. Untuk menunjang studi ini di perlukan sampel volume lalu lintas, antrian dan tundaan dengan survey lapangan pada kondisi eksisting yang di laksanakan pada 3 hari di mulai pada hari senin, 13 Februari 2017, Rabu, 15 Februari 2017, dan Sabtu, 18 Februari 2017. Metode evaluasi ini menggukan pedoman Manual Kapasitas Jalan Indonesia 1997 dan menggunakan Peraturan Menteri Perhubungan 96 Tahun 2015. Hasil survey diperoleh total arus volume tertinggi terjadi pada kondisi eksisting pada Jl. Ranu Grati (Pendekat Barat) hari Senin, 13 Februari 2017 yaitu sebesar kapasitas 1438.59 smp/jam, derajarat kejenuhan (DS) 1.18, panjang antrian 605.63 m, tundaan 361.74 det/smp dan tingkat pelayanan F. Dari ketiga alternatif yang dikaji, didapatkan altenatif yang memenuhi syarat adalah alternatif 3, sehingga alternatif 3 yang bisa mengatasi permasalahan lalu lintas di lokasi dengan optimasi waktu siklus & perencanaan pelebaran geometrik, Wmasuk selebar 1.5 m sepanjang 200 m pada pendekat barat dan Wmasuk selebar 2 m sepanjang 10 m pada pendekat selatan serta belok kiri secara langsung. Sehingga dapat mengurangi nilai kapasitas sebesar 2117.93 derajat kejenuhan 0.80, panjang antrian 91.21 m dan tundaan 12.38 kend/det dalam kategori tingkat pelayanan B. Kata Kunci : karakteristik simpang, kinerja simpang, tundaan, antrian

    Suspected sepsis: summary of NICE guidance

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    The UK Parliamentary and Health Service Ombudsman inquiry “Time to Act” found failures in the recognition, diagnosis, and early management of those who died from sepsis, which triggered this guidance. In sepsis the body’s immune and coagulation systems are switched on by an infection and cause one or more body organs to malfunction with variable severity. The condition is life threatening. Although most people with infection do not have and will not develop sepsis, non-specific signs and symptoms can lead to late recognition of people who might have sepsis. We would like clinicians to “think sepsis” and recognise symptoms and signs of potential organ failure when they assess someone with infection, in a similar way to thinking “Could this chest pain be cardiac in origin?”This guidance provides a pragmatic approach for patients with infection who are assessed in the community, emergency departments, and hospitals by a wide range of general and specialist healthcare professionals. It includes guidance on assessment of risk factors followed by a detailed structured assessment of potential clinical signs and symptoms of concern.Definitions of sepsis have been developed, but these offer limited explanation on how to confirm or rule out the diagnosis in general clinical settings or in the community. Current mechanisms to diagnose sepsis and guidelines for use largely apply to critical care settings such as intensive care. We recognised a need for better recognition of sepsis in non-intensive settings and for the diagnosis to be entertained sooner.While sepsis is multifactorial and rarely presents in the same way, the Guideline Development Group considered that use of an easy, structured risk assessment may help clinicians identify those most severely ill who require immediate potentially lifesaving treatment. This guideline ensures that patients defined as having sepsis by recent definitions are, as a minimum, assessed as moderate-high risk. This guidance is also about appropriate de-escalation if sepsis is unlikely and broad spectrum antibiotics or hospital admission are not appropriate.This article summarises recommendations from the National Institute for Health and Care Excellence (NICE) guideline for the recognition, diagnosis, and management of sepsis in children and adults. Recommendations and the clinical pathway are available via the NICE website, and the UK Sepsis Trust tools are being revised to align with this guidance. This article is accompanied by an infographic, which displays the NICE guideline as a decision making tool

    Biogeography of species richness gradients:Linking adaptive traits, demography and diversification

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    Here we review how adaptive traits contribute to the emergence and maintenance of species richness gradients through their influence on demographic and diversification processes. We start by reviewing how demographic dynamics change along species richness gradients. Empirical studies show that geographical clines in population parameters and measures of demographic variability are frequent along latitudinal and altitudinal gradients. Demographic variability often increases at the extremes of regional species richness gradients and contributes to shape these gradients. Available studies suggest that adaptive traits significantly influence demographic dynamics, and set the limits of species distributions. Traits related to thermal tolerance, resource use, phenology and dispersal seem to play a significant role. For many traits affecting demography and/or diversification processes, complex mechanistic approaches linking genotype, phenotype and fitness are becoming progressively available. In several taxa, species can be distributed along adaptive trait continuums, i.e. a main axis accounting for the bulk of inter-specific variation in some correlated adaptive traits. It is shown that adaptive trait continuums can provide useful mechanistic frameworks to explain demographic dynamics and diversification in species richness gradients. Finally, we review the existence of sequences of adaptive traits in phylogenies, the interactions of adaptive traits and community context, the clinal variation of traits across geographical gradients, and the role of adaptive traits in determining the history of dispersal and diversification of clades. Overall, we show that the study of demographic and evolutionary mechanisms that shape species richness gradients clearly requires the explicit consideration of adaptive traits. To conclude, future research lines and trends in the field are briefly outlined

    mTOR pathway inhibition as a new therapeutic strategy in epilepsy and epileptogenesis.

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    Several preclinical and some clinical studies have revealed that the mammalian target of rapamycin (mTOR) signaling pathway is involved in both genetic and acquired epilepsy syndromes. Excessive activation of mTOR signaling, as a consequence of loss-of-function of genes encoding for tuberous sclerosis complex (TSC) 1 and 2, is linked to the development of cortical malformations and epilepsy. This mTOR hyperactivation is associated with different epileptogenic conditions under the term of 'mTORopathies' such as tuberous sclerosis, focal cortical dysplasia, hemimegalencephaly and ganglioglioma. mTOR overactivation produces brain abnormalities that include dysplastic neurons, abnormal cortical organization and astrogliosis. mTOR inhibitors (e.g. rapamycin) have consistent protective effects in various genetic (e.g. TSC models and WAG/Rij rats) and acquired (e.g. kainate or pilocarpine post-status epilepticus) epilepsy animal models. Furthermore, clinical studies in patients with TSC and cortical dysplasia (CD) have confirmed the effectiveness of mTOR inhibitors also in epileptic patients. Therefore, mTOR is currently a very good candidate as a target for epilepsy and epileptogenesis. This review describes the relevance of the mTOR pathway to epileptogenesis and its potential as a therapeutic target in epilepsy treatment by presenting the most recent findings on mTOR inhibitors

    Fintechs e a Economia Digital: Desafios e Perspectivas

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    TCC (graduação) - Universidade Federal de Santa Catarina. Campus Araranguá. Tecnologias da Informação e ComunicaçãoCom a vinda da globalização e o desenvolvimento de uma sociedade cada vez mais conectada, criou-se uma disputa acirrada das grandes corporações pelos clientes, de forma que armas como tecnologia e inovação vieram a se tornar altamente valiosas para a sobrevivência das empresas no mercado. Com instituições financeiras e bancos também não é diferente, isso se prova pela rápida evolução das chamadas Fintechs baseadas inteiramente em tecnologia, prometendo menos burocracia e, acesso facilitado à realização de serviços financeiros de forma majoritariamente ou, na maioria das vezes, totalmente digital. Desta forma, neste trabalho se examina os desafios e perspectivas destas novas instituições financeiras baseadas na tecnologia, possibilitando as transformações para uma economia digital.With the advent of globalization and the development of an increasingly connected society, customers have created a fierce competition of large corporations, so that weapons like technology and innovation have become highly valuable for the survival of companies in the market. With financial institutions and banks it is no different either, this is evidenced by the rapid evolution of Fintechs calls based entirely on technology, promising less bureaucracy and easier access to the realization of financial services in a majority or, in most cases, totally digital. Nevertheless, when it comes to money, there are several questions about the impacts these startups can have on society where banking services are highly bureaucratic and full of rules and fees

    Penggunaan Metode Demonstrasi Untuk Meningkatkan Keaktifan Dalam Pembelajaran IPS Pada Siswa Kelas IV SDN 1 Cepokosawit Sawit Boyolali Tahun Pelajaran 2012/2013

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    Penelitian ini bertujuan untuk meningkatkan keaktifan dalam pembelajaran IPA melalui penggunaan metode demonstrasi pada siswa kelas IV SDN 1 Cepokosawit Kecamatan Sawit Kabupaten Boyolali tahun pelajaran 2012/2013. Sebelum diberikan tindakan, keaktifan belajar IPA peserta didik kurang dan guru sudah mengupayakan alternatif pemecahannya dengan menggunakan beberapa metode. Penerapan metode tersebut ternyata belum mampu meningkatkan keaktifan siswa dalam pembelajaran IPA. Solusi yang ditawarkan dalam penelitian ini adalah dengan menggunakan metode demonstrasi. Subjek pelaksanaan tindakan adalah siswa kelas IV SD Negeri 1 Cepokosawit yang berjumlah 12 anak. Teknik pengumpulan data menggunakan metode observasi, dokumentasi dan wawancara. Analisis data menggunakan teknik analisis kritis, analisis data deskriptif komparatif dan analisis data model alir. Penelitian tindakan kelas ini dilakukan melalui dua siklus. Prosedur dalam penelitian ini terdapat empat tahap yaitu perencanaan, pelaksanaan, observasi dan evaluasi, analisis dan refleksi. Hasil penelitian ini menunjukkan bahwa keaktifan siswa pada pembelajaran IPA sebelum diadakan tindakan menggunakan metode demonstrasi sebanyak 4 anak (33%). Setelah dilakukan tindakan yang telah disepakati yaitu menerapkan metode demonstrasi pada siklus I keaktifan siswa pada pembelajaran IPA meningkat menjadi 8 anak (67%) dan pada siklus II meningkat menjadi 10 anak (83%). Berdasarkan hasil analisis data pada penelitian tindakan ini hipotesis yang menyatakan “diduga melalui penggunaan metode demonstrasi dapat meningkatkan keaktifan siswa pada pembelajaran IPA pada siswa kelas IV SDN 1 Cepokosawit Kecamatan Sawit Kabupaten Boyolali tahun pelajaran 2012/2013” terbukti dan dapat diterima kebenarannya
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