Achieving Very High PV Penetration

This article argues that optimally deployed intermittency solutions could affordably transform solar power generation into the firm power delivery system modern economies require, thereby enabling very high solar penetration and the displacement conventional power generation. The optimal deployment of these high‐penetration enabling solutions imply the existence of a healthy power grid, and therefore imply a central role for utilities and grid operators. This article also argues that a value‐based electricity compensation mechanism, recognizing the multifaceted, penetration‐dependent value and cost of solar energy, and capable of shaping consumption patterns to optimally match resource and demand, would be an effective vehicle to enable high solar penetration and deliver affordable firm power generation

Risk of colorectal cancer seven years after flexible sigmoidoscopy screening: randomised controlled trial

Objective To determine the risk of colorectal cancer after screening with flexible sigmoidoscopy

Neuromuscular performance of paretic versus non-paretic plantar flexors after stroke.

The objective of this study was to compare the neuromuscular function of the paretic and non-paretic plantar flexors (i.e. soleus, gastrocnemius medialis, lateralis) in chronic stroke patients. It was hypothesized that the contractile rate of force development (RFD) and neural activation, assessed by electromyogram (EMG) and V-waves normalized to the M-wave, and voluntary activation (twitch interpolation) would be reduced during plantar flexor maximum voluntary isometric contraction and that the evoked muscle twitch properties would be reduced in the paretic limb. Ten chronic stroke survivors completed the study. The main findings were that the paretic side showed deteriorated function compared to the non-paretic leg in terms of (1) RFD in all analyzed time windows from force onset to 250 ms, although relative RFD (i.e. normalized to maximum voluntary force) was similar; (2) fast neural activation (for most analyzed time windows), assessed by EMG activity in time windows from EMG onset to 250 ms; (3) V-wave responses (except for gastrocnemius medialis); (4) voluntary activation; (5) the evoked peak twitch force, although there was no evidence of intrinsic muscle slowing; (6) EMG activity obtained at maximal voluntary force. In conclusion, this study demonstrates considerable neuromuscular asymmetry of the plantar flexors in chronic stroke survivors. Effective rehabilitation regimes should be investigated

Clinical Study Arm Crank and Wheelchair Ergometry Produce Similar Peak Oxygen Uptake but Different Work Economy Values in Individuals with Spinal Cord Injury

Objective. To study whether values for peak oxygen uptake (VO 2peak ) and work economy (WE) at a standardized workload are different when tested by arm crank ergometry (ACE) and wheelchair ergometry (WCE). Methods. Twelve paraplegic men with spinal cord injury (SCI) in stable neurological condition participated in this cross-sectional repeated-measures study. We determined VO 2peak and peak power output (PO peak ) values during ACE and WCE in a work-matched protocol. Work economy was tested at a standardized workload of 30 Watts (W) for both ACE and WCE. Results. There were no significant differences in VO 2peak (mL⋅kg −1 ⋅min −1 ) between ACE (27.3 ± 3.2) and WCE (27.4 ± 3.8) trials, and a Bland-Altman plot shows that findings are within 95% level of agreement. WE or oxygen consumption at 30 W (VO 2-30W ) was significantly lower during WCE compared to ACE ( < 0.039). Mean (95% CI) PO peak (W) were 130 (111-138) and 100 (83-110) during ACE and WCE, respectively. Conclusion. The findings in the present study support the use of both ACE and WCE for testing peak oxygen uptake. However, WE differed between the two test modalities, meaning that less total energy is used to perform external work of 30 W during wheelchair exercise when using this WCE (VP100 Handisport ergometer). Clinical Trials Protocol Record is NCT00987155/4.2007.2271

Archäologie als Kunst. Archäologische Objekte und Verfahren in der bildenden Kunst des 18. Jahrhunderts und der Gegenwart

Der Band enthält Beiträge zu zwei Veranstaltungen, die ausgehend von Ausstellungen in Köln und Salzburg die Wiedergabe archäologischer Objekte und Verfahrens­ weisen in der Bildenden Kunst des 18. Jahrhunderts und der Gegenwart behandelten. Die Beiträge des ersten Teils zeigen, wie sich die Vor­ stellungen des G. B. Piranesi von der Größe Roms in seinen hybriden Antikenrekonstruktionen und in seinen antikisierenden Reliefs niederschlugen. Auch die gleich­ zeitig entstandenen Korkmodelle sowie Daktyliotheken, Wandgemälde, Figuren und Gefäße aus Porzellan visuali­ sierten Wissen von der römischen Antike, hielten es in der aktuellen Lebenswelt der Zeitgenossen präsent, regten zum Gespräch darüber an und formatierten so den historischen Diskurs. Die Beiträge des zweiten Teils gehen von der Frage aus, was es für die Archäologie als Wissenschaft bedeutet, wenn zeitgenössische Künstler ihre Gegenstände, Metho­den und Ordnungssysteme aufnehmen und weiterent­ wickeln