66,295 research outputs found
Intra-hour cloud index forecasting with data assimilation
We introduce a computational framework to forecast cloud index (CI)fields for up to one hour on a spatial domain that covers a city. Such intra-hour CI forecasts are important to produce solar power forecasts of utility scale solar power and distributed rooftop solar. Our method combines a 2D advection model with cloud motion vectors (CMVs)derived from a mesoscale numerical weather prediction (NWP)model and sparse optical flow acting on successive, geostationary satellite images. We use ensemble data assimilation to combine these sources of cloud motion information based on the uncertainty of each data source. Our technique produces forecasts that have similar or lower root mean square error than reference techniques that use only optical flow, NWP CMV fields, or persistence. We describe how the method operates on three representative case studies and present results from 39 cloudy days
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New and emerging technologies for the treatment of inherited retinal diseases: a horizon scanning review.
The horizon scanning review aimed to identify new and emerging technologies in development that have the potential to slow or stop disease progression and/or reverse sight loss in people with inherited retinal diseases (IRDs). Potential treatments were identified using recognized horizon scanning methods. These included a combination of online searches using predetermined search terms, suggestions from clinical experts and patient and carer focus groups, and contact with commercial developers. Twenty-nine relevant technologies were identified. These included 9 gene therapeutic approaches, 10 medical devices, 5 pharmacological agents, and 5 regenerative and cell therapies. A further 11 technologies were identified in very early phases of development (typically phase I or pre-clinical) and were included in the final report to give a complete picture of developments 'on the horizon'. Clinical experts and patient and carer focus groups provided helpful information and insights, such as the availability of specialised services for patients, the potential impacts of individual technologies on people with IRDs and their families, and helped to identify additional relevant technologies. This engagement ensured that important areas of innovation were not missed. Most of the health technologies identified are still at an early stage of development and it is difficult to estimate when treatments might be available. Further, well designed trials that generate data on efficacy, applicability, acceptability, and costs of the technologies, as well as the long-term impacts for various conditions are required before these can be considered for adoption into routine clinical practice
Search for eta-mesic Helium with the WASA-at-COSY detector
A search for the 4He-eta bound state via exclusive measurement of the
excitation function for the dd->3Heppi- reaction, was performed at the Cooler
Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were
taken during a slow acceleration of the beam from 2.185 GeV/c to 2.400 GeV/c
crossing the kinematic threshold for the eta production in the dd -> 4He-eta
reaction at 2.336 GeV/c. The corresponding excess energy in the 4He-eta system
varied from -51.4 MeV to 22 MeV. The shape of the excitation function for the
dd -> 3Heppi- was examined. No signal of the 4He-eta bound state was observed
in the excitation function.Comment: 4 pages, 5 figures, to appear in proceedings of MESON201
Effect of acute severe hypoxia on peripheral fatigue and endurance capacity in healthy humans
Effect of acute severe hypoxia on peripheral
fatigue and endurance capacity in healthy humans. Am J Physiol
Regul Integr Comp Physiol 292: R598–R606, 2007. First published
September 7, 2006; doi:10.1152/ajpregu.00269.2006.—We hypothesized
that severe hypoxia limits exercise performance via decreased
contractility of limb locomotor muscles. Nine male subjects [mean
SE maximum O2 uptake (V˙ O2 max) 56.5 2.7 ml kg 1 min 1]
cycled at 90% V˙ O2 max to exhaustion in normoxia [NORM-EXH;
inspired O2 fraction (FIO2) 0.21, arterial O2 saturation (SpO2)
93 1%] and hypoxia (HYPOX-EXH; FIO2 0.13, SpO2 76
1%). The subjects also exercised in normoxia for a time equal to that
achieved in hypoxia (NORM-CTRL; SpO2 96 1%). Quadriceps
twitch force, in response to supramaximal single (nonpotentiated and
potentiated 1 Hz) and paired magnetic stimuli of the femoral nerve
(10–100 Hz), was assessed pre- and at 2.5, 35, and 70 min postexercise.
Hypoxia exacerbated exercise-induced peripheral fatigue, as
evidenced by a greater decrease in potentiated twitch force in
HYPOX-EXH vs. NORM-CTRL ( 39 4 vs. 24 3%, P
0.01). Time to exhaustion was reduced by more than two-thirds in
HYPOX-EXH vs. NORM-EXH (4.2 0.5 vs. 13.4 0.8 min, P
0.01); however, peripheral fatigue was not different in HYPOX-EXH
vs. NORM-EXH ( 34 4 vs. 39 4%, P 0.05). Blood lactate
concentration and perceptions of limb discomfort were higher
throughout HYPOX-EXH vs. NORM-CTRL but were not different at
end-exercise in HYPOX-EXH vs. NORM-EXH. We conclude that
severe hypoxia exacerbates peripheral fatigue of limb locomotor
muscles and that this effect may contribute, in part, to the early
termination of exercise
An investigation into the use of 3G mobile communications to provide telehealth services in rural KwaZulu-Natal
This article has been made available through the Brunel Open Access Publishing Fund.Abstract Background: We investigated the use of third-generation (3G) mobile communications to provide telehealth services in remote health clinics in rural KwaZulu-Natal, South Africa. Materials and Methods: We specified a minimal set of services as our use case that would be representative of typical activity and to provide a baseline for analysis of network performance. Services included database access to manage chronic disease, local support and management of patients (to reduce unnecessary travel to the hospital), emergency care (up to 8 h for an ambulance to arrive), e-mail, access to up-to-date information (Web), and teleclinics. We made site measurements at a representative set of health clinics to determine the type of coverage (general packet radio service [GPRS]/3G), its capabilities to support videoconferencing (H323 and Skype™ [Microsoft, Redmond, WA]) and audio (Skype), and throughput for transmission control protocol (TCP) to gain a measure of application performance. Results: We found that none of the remote health clinics had 3G service. The GPRS service provided typical upload speed of 44 kilobits per second (Kbps) and download speed of 64 Kbps. This was not sufficient to support any form of videoconferencing. We also observed that GPRS had significant round trip time (RTT), in some cases in excess of 750 ms, and this led to slow start-up for TCP applications. Conclusions: We found audio was always so broken as to be unusable and further observed that many applications such as Web access would fail under conditions of very high RTT. We found some health clinics were so remote that they had no mobile service. 3G, where available, had measured upload speed of 331 Kbps and download speed of 446 Kbps and supported videoconferencing and audio at all sites, but we frequently experienced 3G changing to GPRS. We conclude that mobile communications currently provide insufficient coverage and capability to provide reliable clinical services and would advocate dedicated wireless services where reliable communication is essential and use of store and forward for mobile applications.The Royal Society, United Kingdom
Early assessment of vestibular function after unilateral cochlear implant surgery
Introduction : Cochlear implantation (CI) has been reported to negatively effect on the vestibular function. The study of the vestibular function has variably been conducted by different types of diagnostic tools. The combined use of modern, rapidly performable diagnostic tools could reveal useful for standardizing the evaluation protocol.
Methods: In a group of 28 subjects undergoing CI, the video Head Impulse Test (vHIT), the cervical Vestibular Evoked Myogenic Potentials (cVEMPS) and the short-form of Dizziness Handicap Inventory (DHI) questionnaire were investigated pre-operatively and post-operatively (implant on and off) in both the implanted and the contralateral, non-implanted ear. All surgeries were performed with a round window approach (RWA), except for three otosclerosis cases were the extended RWA (eRWA) was used.
Results: The vHIT of the lateral semicircular canal showed a pre-operative vestibular involvement in nearly 50% of the cases, whilst the three canals were contemporarily affected in only 14% of them. In all the hypo-functional subjects, cVEMPs were absent. A low VOR gain in all the investigated SSCC was found in 4 subjects (14%). In those subjects, (21.7%) in whom cVEMPs were pre-operatively present and normal in the operated side, absence of response was post-operatives recorded.
Discussion/Conclusion: The vestibular protocol applied for the study showed to be appropriate for distinguishing between the CI operated and the non-operated ear. In this regard, cVEMPs showed to be more sensitive than vHIT for revealing a vestibular sufferance after CI, although without statistical significance. Finally, the use of the RWA surgery was apparently not avoiding signs of vestibular impairment to occur
Strategi Peningkatan Produksi USAha Tani Penangkaran Benih Padi Bersertifikat
Tujuan penelitian ini adalah untuk mendeskripsikan faktor-faktor internal dan eksternal dalam meningkatkan produksi USAha tani penangkaran benih padi. Serta menganalisis strategi peningkatan produksi USAha tani penangkaran benih padi di Desa Tumpatan nibung Kecamatan Batang Kuis Kabupaten Deli Serdang. Metode analisis yang digunakan adalah metode analisis deskriptif dan analisis SWOT. Hasil penelitian menunjukkan bahwa Faktor internal dan faktor eksternal dalam peningkatan produksi penangkaran benih padi di daerah penelitian terdiri dari kualitas fisik produksi yang sangat baik, pemanfaatan teknologi yang baik, kepercayaan pembeli gabah sangat tinggi, bahan baku benih tersedia ketika musim tanam. Ketersediaan lahan yang minim, modal USAha tani, sarana prasarana produksi yang minim. adanyapenyuluh yang aktif, permintaan benih sangat tinggi, pemerintah sangat mendukung kesejahteraan petani. Perubahan iklim dan cuaca, tidak adanya lembaga keuangan dengan kredit ringan, adanya alih fungsi lahan. Strategi yang diperoleh adalah strategi diversifikasi atau strategi ST (Strengths – Threats) yaitu menggunakan kekuatan untuk meminimalkan ancaman yang ad
The effect of the systemic inflammatory response on plasma vitamin 25 (OH) D concentrations adjusted for albumin
<b>Aim</b><p></p>
To examine the relationship between plasma 25(OH)D, CRP and albumin concentrations in two patient cohorts.<p></p>
<b>Methods</b><p></p>
5327 patients referred for nutritional assessment and 117 patients with critical illness were examined. Plasma 25 (OH) D concentrations were measured using standard methods. Intra and between assay imprecision was <10%.<p></p>
<b>Result</b><p></p>
In the large cohort, plasma 25 (OH) D was significantly associated with CRP (rs = −0.113, p<0.001) and albumin (rs = 0.192, p<0.001). 3711 patients had CRP concentrations ≤10 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were significantly lower from 35 to 28 to 14 nmol/l (p<0.001). This decrease was significant when albumin concentrations were reduced between 25–34 g/L (p<0.001) and when albumin <25 g/L (p<0.001). 1271 patients had CRP concentrations between 11–80 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were significantly lower from 31 to 24 to 19 nmol/l (p<0.001). This decrease was significant when albumin concentration were 25–34 g/L (p<0.001) and when albumin <25 g/L (p<0.001). 345 patients had CRP concentrations >80 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were not significantly altered varying from 19 to 23 to 23 nmol/l. Similar relationships were also obtained in the cohort of patients with critical illness.<p></p>
<b>Conclusion</b><p></p>
Plasma concentrations of 25(OH) D were independently associated with both CRP and albumin and consistent with the systemic inflammatory response as a major confounding factor in determining vitamin D status.<p></p>
On hyperbolicity of SU(2)-equivariant, punctured disc bundles over the complex affine quadric
Given a holomorphic line bundle over the complex affine quadric , we
investigate its Stein, SU(2)-equivariant disc bundles. Up to equivariant
biholomorphism, these are all contained in a maximal one, say .
By removing the zero section to one obtains the unique Stein,
SU(2)-equivariant, punctured disc bundle over which contains entire
curves. All other such punctured disc bundles are shown to be Kobayashi
hyperbolic.Comment: 15 pages, v2: minor changes, to appear in Transformation Group
Model Kontrak Belajar Bermuatan Nilai Sosial-Budaya Dalam Bimbingan Akademik Mahasiswa
This research was based on the empirical phenomenon concerning the ineffectiveness of implicit contract in academic guidance related, in particular, to students\u27 study programming. In this research, students\u27 understanding and expectations on contract model for the effectiveness of guidance were identified and abstracted. A contract model, in which each participant specifies who is to do what, under which circumstances, times, and places, was negotiated. Taking into account socio-cultural values, the contract model was constructed and applied in natural manner. The effectiveness of the model was seen from the students\u27 point of view. The study employed theapproaches of ‘basic or generic qualitative study\u27 and ‘action research\u27
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