16 research outputs found

    Sustainable Development is the only path to achieve the green economy

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    Sustainable development is the management of renewable resources for the good of the entire human and natural community. Built into this concept is an awareness of the animal and plant life of the surrounding environment .The goal of sustainable development is to provide resources for the use of present populations without compromising the availability of those resources for future generations, and without causing environmental damage that challenges the survival of natural ecosystems. Consequently, sustainable economies cannot be based on the use of non-renewable resources. Ultimately, sustainable economies must be supported by the use of renewable resources such as biological productivity, and solar, wind, geothermal, and biomass energy sources. However, even renewable resources may be subjected to overexploitation and other types of environmental degradation. Central to the notion of sustainable development is the requirement that renewable resources are utilized in ways that do not diminish their capacity for renewal, so that they will always be present to sustain future generations of humans. On the other hand, Egypt welcomes the concept of the green economy to achieve sustainable development ,within the framework of respect for national priorities of each country, in order to achieve more decent work opportunities, and developments continued, and use environmental resources. Egypt have passed already in the implementation of a number of pilot projects in this regard, and look forward to witnessing the next stage for more cooperation with development. The energy is the main driver of economic and social development with the necessity to development of primary energy resources and the proper management and use of the most important policies and development strategies Egypt depends in achieving economic development and technological several sources of energy available to a power and petroleum and natural gas, but that recently Egypt has seen a severe lack of energy due to the following reasons Increased energy consumption rate - Lower crude oil and gas production rates in the country - Some electricity production plants with low efficiency - increasing  proportion of commercial waste- Slow  expansion  of the  use  of  alternative  energy .In this sense the Ministry of Environment has searched for alternative sources of energy assessing its environmental impact and its economic and social impact at the same time and take measures and actions that would raise sustainable proportion of renewable energy in the Egyptian energy mix and working to reduce the pressures of climate change where can these measures can contribute to maximize the utilization of alternative energy resources and traditional such as the use of solid waste as well as alternative fuels and use them as a form of alternative energy.</p

    Comparison of automated infarct core volume measures between non-contrast computed tomography and perfusion imaging in acute stroke code patients evaluated for potential endovascular treatment

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    Introduction: Patients with small core infarction and salvageable penumbra are likely to benefit from endovascular treatment (EVT). As computed tomography perfusion imaging (CTP) is not always available 24/7 for patient selection, many patients are transferred to stroke centers for CTP. We compared automatically measured infarct core volume (NCCTcore) from the non-contrast computed tomography (NCCT) with ischemic core volume (CTPcore) from CTP and the outcome of EVT to clarify if NCCTcore measurement alone is sufficient to identify patients that benefit from transfer to stroke centers for EVT. Patients and methods: We included all consecutive stroke-code patients imaged with both NCCT and CTP at Helsinki University Hospital during 9/2016-01/2018. NCCTcore and CTPcore volumes were automatically calculated from the acute NCCT images. Follow-up infarct volume (FIV) was measured from 24 h follow-up NCCT to evaluate efficacy of EVT. To study whether NCCTcore could be used to identify patients eligible to EVT, we subgrouped patients based on NCCTcore volumes (>50 mL and > 70 mL). Results: Out of 1743 patients, baseline NCCTcore, CTPcore and follow-up NCCT was available for 288 patients. Median time from symptom onset to baseline imaging was 74 min (IQR 52-118), and time to follow-up imaging 24.15 h (22.25-26.33). Baseline NCCTcore was 20 mL (10-42), CTPcore 4 mL (0-16), and FIV 5 mL (1-49). Out of 288 patients, 23 had NCCTcore > 70 mL and 26 had CTPcore > 70 mL. NCCTcore and CTPcore performed similarly well in predicting large FIV (>70 ml). Conclusion: NCCTcore is a promising tool to identify patients that are not eligible to EVT due to large ischemic cores at baseline imaging.Peer reviewe

    Is infarct core growth linear? Infarct volume estimation by computed tomography perfusion imaging

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    Objectives Current guidelines for recanalization treatment are based on the time elapsed between symptom onset and treatment and visualization of existing penumbra in computed tomography perfusion (CTP) imaging. The time window for treatment options relies on linear growth of infarction although individual infarct growth rate may vary. We aimed to test how accurately the estimated follow-up infarct volume (eFIV) can be approximated by using a linear growth model based on CTP baseline imaging. If eFIV did not fall within the margins of +/- 19% of the follow-up infarct volume (FIV) measured at 24 h from non-enhanced computed tomography images, the results would imply that the infarct growth is not linear. Materials and Methods All consecutive endovascularly treated (EVT) patients from 11/2015 to 9/2019 at the Helsinki University Hospital with large vessel occlusion (LVO), CTP imaging, and known time of symptom onset were included. Infarct growth rate was assumed to be linear and calculated by dividing the ischemic core volume (CTPcore) by the time from symptom onset to baseline imaging. eFIV was calculated by multiplying the infarct growth rate with the time from baseline imaging to recanalization or in case of futile recanalization to follow-up imaging at 24 h, limited to the penumbra. Collateral flow was estimated by calculating hypoperfusion intensity ratio (HIR). Results Of 5234 patients, 48 had LVO, EVT, CTP imaging, and known time of symptom onset. In 40/48 patients (87%), infarct growth was not linear. HIR did not differ between patients with linear and nonlinear growth (p > .05). As expected, in over half of the patients with successful recanalization eFIV exceeded FIV. Conclusions Infarct growth was not linear in most patients and thus time elapsed from symptom onset and CTPcore appear to be insufficient parameters for clinical decision-making in EVT candidates.Peer reviewe

    Age-Related Differences in Functional Nodes of the Brain Cortex – A High Model Order Group ICA Study

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    Functional MRI measured with blood oxygen dependent (BOLD) contrast in the absence of intermittent tasks reflects spontaneous activity of so-called resting state networks (RSN) of the brain. Group level independent component analysis (ICA) of BOLD data can separate the human brain cortex into 42 independent RSNs. In this study we evaluated age-related effects from primary motor and sensory, and, higher level control RSNs. One hundred sixty-eight healthy subjects were scanned and divided into three groups: 55 adolescents (ADO, 13.2 ± 2.4 years), 59 young adults (YA, 22.2 ± 0.6 years), and 54 older adults (OA, 42.7 ± 0.5 years), all with normal IQ. High model order group probabilistic ICA components (70) were calculated and dual-regression analysis was used to compare 21 RSN's spatial differences between groups. The power spectra were derived from individual ICA mixing matrix time series of the group analyses for frequency domain analysis. We show that primary sensory and motor networks tend to alter more in younger age groups, whereas associative and higher level cognitive networks consolidate and re-arrange until older adulthood. The change has a common trend: both spatial extent and the low frequency power of the RSN's reduce with increasing age. We interpret these result as a sign of normal pruning via focusing of activity to less distributed local hubs

    The Application of the Novel Grading Scale (Lawton-Young Grading System) to Predict the Outcome of Brain Arteriovenous Malformation

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    BACKGROUND: A supplementary grading scale (Supplemented Spetzler-Martin grade, Supp-SM) was introduced in 2010 as a refinement of the SM system to improve preoperative risk prediction of brain arteriovenous malformations (AVMs). OBJECTIVE: To determine the ability to predict surgical outcomes using the Supp-SM grading scale. METHODS: This retrospective study was conducted on 200 patients admitted to the Helsinki University Hospital between 2000 and 2014. The validity of the Supp-SM and SM grading systems was compared using the area under the receiver operating characteristic (AUROC) curves, with respect to the change between preoperative and early (3-4 mo) as well as final postoperative modified Rankin Scale (mRS) scores. RESULTS: The performance of the Supp-SM was superior to that of the SM grading scale in the early follow-up (3-4 mo): AUROC = 0.57 (95% confidence interval [CI]: 0.49-0.65) for SM and AUROC = 0.67 (95% CI: 0.60-0.75) for Supp-SM. The Supp-SM performance continued improving over SM at the late follow-up: AUROC = 0.63 (95% CI: 0.55-0.71) for SM and AUROC = 0.70 (95% CI: 0.62-0.77) for Supp-SM. The perforating artery supply, which is not part of either grading system, plays an important role in the early follow-up outcome (P = .008; odds ratio: 2.95; 95% CI: 1.32-6.55) and in the late follow-up outcome (P <.001; odds ratio: 5.89; 95% CI: 2.49-13.91). CONCLUSION: The Supp-SM grading system improves the outcome prediction accuracy and is a feasible alternative to the SMS, even for series with higher proportion of high-grade AVMs. However, perforators play important role on the outcome.Peer reviewe

    Exploring functional brain networks using independent component analysis:functional brain networks connectivity

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    Abstract Functional communication between brain regions is likely to play a key role in complex cognitive processes that require continuous integration of information across different regions of the brain. This makes the studying of functional connectivity in the human brain of high importance. It also provides new insights into the hierarchical organization of the human brain regions. Resting-state networks (RSNs) can be reliably and reproducibly detected using independent component analysis (ICA) at both individual subject and group levels. A growing number of ICA studies have reported altered functional connectivity in clinical populations. In the current work, it was hypothesized that ICA model order selection influences characteristics of RSNs as well as their functional connectivity. In addition, it was suggested that high ICA model order could be a useful tool to provide more detailed functional connectivity results. RSNs’ characteristics, i.e. spatial features, volume and repeatability of RSNs, were evaluated, and also differences in functional connectivity were investigated across different ICA model orders. ICA model order estimation had a significant impact on the spatial characteristics of the RSNs as well as their parcellation into sub-networks. Notably, at low model orders neuroanatomically and functionally different units tend to aggregate into large singular RSN components, while at higher model orders these units become separate RSN components. Disease-related differences in functional connectivity also seem to alter as a function of ICA model order. The volume of between-group differences reached maximum at high model orders. These findings demonstrate that fine-grained RSNs can provide detailed, disease-specific functional connectivity alterations. Finally, in order to overcome the multiple comparisons problem encountered at high ICA model orders, a new framework for group-ICA analysis was introduced. The framework involved concatenation of IC maps prior to permutation tests, which enables statistical inferences from all selected RSNs. In SAD patients, this new correction enabled the detection of significantly increased functional connectivity in eleven RSNs.Tiivistelmä Toiminnallisten aivoalueiden välinen viestintä on todennäköisesti avainasemassa kognitiivisissa prosesseissa, jotka edellyttävät jatkuvaa tiedon integraatiota aivojen eri alueiden välillä. Tämä tekee ihmisaivojen toiminnallisen kytkennällisyyden tutkimuksesta erittäin tärkeätä. Kytkennälllisyyden tutkiminen antaa myös uutta tietoa ihmisaivojen osa-alueiden välisestä hierarkiasta. Aivojen hermoverkot voidaan luotettavasti ja toistettavasti havaita lepotilan toiminnasta yksilö- ja ryhmätasolla käyttämällä itsenäisten komponenttien analyysia (engl. Independent component analysis, ICA). Yhä useammat ICA-tutkimukset ovat raportoineet poikkeuksellisia toiminnallisen konnektiviteetin muutoksia kliinisissä populaatioissa. Tässä tutkimuksessa hypotetisoitiin, että ICA:lla laskettaujen komponenttien lukumäärä (l. asteluku) vaikuttaa tuloksena saatujen hermoverkkojen ominaisuuksiin kuten tilavuuteen ja kytkennällisyyteen. Lisäksi oletettiin, että korkea ICA-asteluku voisi olla herkempit tuottamaan yksityiskohtaisia toiminnallisen jaottelun tuloksia. Aivojen lepotilan hermoverkkojen ominaisuudet, kuten anatominen jakautuminen, volyymi ja lepohermoverkkojen havainnoinnin toistettavuus evaluoitin. Myös toiminnallisen kytkennällisyyden erot tutkitaan eri ICA-asteluvuilla. Havaittiin että asteluvulla on huomattava vaikutus aivojen lepotilan hermoverkkojen tilaominaisuuksiin sekä niiden jakautumiseen alaverkoiksi. Pienillä asteluvuilla hermoverkojen neuroanatomisesti erilliset yksiköt pyrkivät keräytymään laajoiksi yksittäisiksi komponenteiksi, kun taas korkeammilla asteluvuilla ne havaitaan erillisinä. Sairauksien aiheuttamat muutokset toiminnallisessa kytkennällisyydessä näyttävät muuttuvan myös ICA asteluvun mukaan saavuttaen maksiminsa korkeilla asteluvuilla. Korkeilla asteluvuilla voidaan havaita yksityiskohtaisia, sairaudelle ominaisia toiminnallisen konnektiviteetin muutoksia. Korkeisiin ICA asteluvun liittyvän tilastollisen monivertailuongelman ratkaisemiseksi kehitimme uuden menetelmän, jossa permutaatiotestejä edeltävien itsenäisten IC-karttoja yhdistämällä voidaan tehdä luotettava tilastollinen arvio yhtä aikaa lukuisista hermoverkoista. Kaamosmasennuspotilailla esimerkiksi kehittämämme korjaus paljastaa merkittävästi lisääntynyttä toiminnallista kytkennällisyyttä yhdessätoista hermoverkossa

    Characteristics and Long-Term Outcome of 127 Children With Cerebral Arteriovenous Malformations

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    Johdanto Lasten aivojen valtimolaskimoepämuodostumista ei ole julkaistu juurikaan väestöpohjaista pitkän aikavälin seurantaa. Tavoite Selventää lasten valtimolaskimoepämuodostumien ominaisuuksia ja pitkän aikavälin toipuminen. Menetelmät Retrospektiivinen analyysi suoritettiin 805 perättäiselle potilaalle, jotka kirjautuivat Töölön sairaalan neurokirurgian klinikkaan vuosien 1942 ja 2014 välillä ja joilla oli aivojen valtimolaskimoepämuodostuma. Potilaat määriteltiin lapsiksi, jos he olivat alle 18-vuotiaita kirjautumisajankohtana. Lapsia verrattiin aikuiskohorttiin. Taudin muuttuvia ilmenemismalleja tarkasteltiin vuosikymmenittäin. Tulokset Potilaat koostuivat 127 lapsesta, joiden keski-ikä oli 12-vuotta. Keskiseuranta-aika oli 21-vuotta (0-62 välillä). Lasten valtimolaskimoepämuodostumat tulivat aikuisia useammin esille aivoverenvuotona, mutta harvemmin epilepsian takia. Tyvitumakkeen, pikkuaivojen ja posteriorisen aivokurkiaisen viereisen alueen valtimolaskimoepämuodostumat olivat lapsilla aikuisia yleisempiä. Otsalohkon ja ohimolohkon valtimolaskimoepämuodostumat olivat puolestaan aikuisilla yleisempiä. Kun sattumalöydöksinä ja epilepsian takia ilmitulleet valtimolaskimoepämuodostumat yleistyivät, aivoverenvuotojen esiintyvyys pieneni kummassakin kohortissa. Kokonaisuudessaan valtimolaskimoepämuodostuma aiheutti 22 (82%) lasten ja 108 (39%) aikuisten kuolemaa. Multivarianttianalyysin jälkeen valtimolaskimoepämuodostuman pieni koko ja sen kirurginen poisto korreloivat suotuisan pitkänajan tuloksen kanssa. Johtopäätökset Lasten valtimolaskimoepämuodostumat tulivat esille useammin aivoverenvuodon takia kuin aikuisilla. Tätä heijasteli myös epileptisen ilmenemisen pienempi prevalenssi lapsissa. Lasten valtimolaskomoepämuodostumat sijaitsivat aikuisia harvemmin lohkoissa tai kuorikerroksella, mutta useammin aivojen syvissä osissa ja pikkuaivoissa. Aivoverenvuotojen esiintyminen korreloi negatiivisesti sattumalta ja epilepsian takia löydettyjen valtimolaskimoepämuodostumien kanssa.Lapsissa valtimolaskimoepämuodostuma oli tärkein kuolleisuuden aiheuttaja, mutta aikuisissa kuolemat johtuivat useammin muista syistä.BACKGROUND: Population-based long-term data on pediatric patients with cerebral arteriovenous malformations (AVMs) are limited. OBJECTIVE: To clarify the characteristics and long-term outcome of pediatric patients with AVM. METHODS: A retrospective analysis was performed on 805 consecutive brain AVM patients admitted to a single center between 1942 and 2014. The patients were defined as children if they were under 18 yr at admission. Children were compared to an adult cohort. Changing patterns of presentation were also analyzed by decades of admission. RESULTS: The patients comprised 127 children with a mean age of 12 yr. The mean follow-up time was 21 yr (range 0-62). Children presented more often with intracerebral hemorrhage (ICH) but less often with epilepsy than adults. Basal ganglia, cerebellar, and posterior paracallosal AVMs were more common in pediatric than in adult patients. Frontal and temporal AVMs, in contrast, were more common in adult than in pediatric patients. As the number of incidentally and epilepsy-diagnosed AVMs increased, ICH rates dropped in both cohorts. In total, 22 (82%) pediatric and 108 (39%) adult deaths were assessed as AVM related. After multivariate analysis, small AVM size and surgical treatment correlated with a favorable long-term outcome. CONCLUSION: Hemorrhagic presentation was more common in children than in adults. This was also reflected as lower prevalence of epileptic presentation in the pediatric cohort. Lobar and cortical AVM locations were less frequent, whereas deep and cerebellar AVMs were more common in children. Hemorrhagic presentation correlated negatively with incidentally and epilepsy-diagnosed AVMs. In children, AVM was a major cause of death, but in adults, other factors contributed more commonly to mortality

    The effect of gray matter ICA and coefficient of variation mapping of BOLD data on the detection of functional connectivity changes in Alzheimer’s disease and bvFTD

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    Abstract Resting-state fMRI results in neurodegenerative diseases have been somewhat conflicting. This may be due to complex partial volume effects of CSF in BOLD signal in patients with brain atrophy. To encounter this problem, we used a coefficient of variation (CV) map to highlight artifacts in the data, followed by analysis of gray matter voxels in order to minimize brain volume effects between groups. The effects of these measures were compared to whole brain ICA dual regression results in Alzheimer’s disease (AD) and behavioral variant frontotemporal dementia (bvFTD). 23 AD patients, 21 bvFTD patients and 25 healthy controls were included. The quality of the data was controlled by CV mapping. For detecting functional connectivity (FC) differences whole brain ICA (wbICA) and also segmented gray matter ICA (gmICA) followed by dual regression were conducted, both of which were performed both before and after data quality control. Decreased FC was detected in posterior DMN in the AD group and in the Salience network in the bvFTD group after combining CV quality control with gmICA. Before CV quality control, the decreased connectivity finding was not detectable in gmICA in neither of the groups. Same finding recurred when exclusion was based on randomization. The subjects excluded due to artifacts noticed in the CV maps had significantly lower temporal signal-to-noise ratio than the included subjects. Data quality measure CV is an effective tool in detecting artifacts from resting state analysis. CV reflects temporal dispersion of the BOLD signal stability and may thus be most helpful for spatial ICA, which has a blind spot in spatially correlating widespread artifacts. CV mapping in conjunction with gmICA yields results suiting previous findings both in AD and bvFTD

    The variability of functional MRI brain signal increases in Alzheimer's disease at cardiorespiratory frequencies

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    Biomarkers sensitive to prodromal or early pathophysiological changes in Alzheimer's disease (AD) symptoms could improve disease detection and enable timely interventions. Changes in brain hemodynamics may be associated with the main clinical AD symptoms. To test this possibility, we measured the variability of blood oxygen level-dependent (BOLD) signal in individuals from three independent datasets (totaling 80 AD patients and 90 controls). We detected a replicable increase in brain BOLD signal variability in the AD populations, which constituted a robust biomarker for clearly differentiating AD cases from controls. Fast BOLD scans showed that the elevated BOLD signal variability in AD arises mainly from cardiovascular brain pulsations. Manifesting in abnormal cerebral perfusion and cerebrospinal fluid convection, present observation presents a mechanism explaining earlier observations of impaired glymphatic clearance associated with AD in humans.Peer reviewe
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