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Background: There are few published reports on the safety and efficacy of stereoelectroencephalography (SEEG) in the presurgical evaluation of pediatric drug-resistant epilepsy. Our objective was to describe institutional experience with pediatric SEEG in terms of (1) insertional complications, (2) identification of the epileptogenic zone and (3) seizure outcome following SEEG-tailored resections. Methods: Retrospective review of 29 patients pediatric drug resistant epilepsy patients who underwent presurgical SEEG between 2005 – 2018. Results: 29 pediatric SEEG patients (15 male; 12.4 ± 4.6 years old) were included in this study with mean follow-up of 6.0 ± 4.1 years. SEEG-related complications occurred in 1/29 (3%)—neurogenic pulmonary edema. A total of 190 multi-contact electrodes (mean of 7.0 ± 2.5per patient) were implanted across 30 insertions which captured 437 electrographic seizures (mean 17.5 ± 27.6 per patient). The most common rationale for SEEG was normal MRI with surface EEG that failed to identify the EZ (16/29; 55%). SEEG-tailored resections were performed in 24/29 (83%). Engel I outcome was achieved following resections in 19/24 cases (79%) with 5.9 ± 4.0 years of post-operative follow-up. Conclusions: Stereoelectroencephalography in presurgical evaluation of pediatric drug-resistant epilepsy is a safe and effective way to identify the epileptogenic zone permitting SEEG-tailored resection.
Vitamin B12 is synthesised in the rumen from cobalt (Co) and has a major role in metabolism in the peri-paturient period, although few studies have evaluated the effect of the dietary inclusion of Co, vitamin B12 or injecting vitamin B12 on the metabolism, health and performance of high yielding dairy cows. A total of 56 Holstein-Friesian dairy cows received one of four treatments from 8 weeks before calving to 8 weeks post-calving: C, no added Co; DC, additional 0.2 mg Co/kg dry matter (DM); DB, additional 0.68 mg vitamin B12/kg DM; IB, intra-muscular injection of vitamin B12 to supply 0.71 mg/cow per day prepartum and 1.42 mg/cow per day post-partum. The basal and lactation rations both contained 0.21 mg Co/kg DM. Cows were weighed and condition scored at drying off, 4 weeks before calving, within 24 h of calving and at 2, 4 and 8 weeks post-calving, with blood samples collected at drying off, 2 weeks pre-calving, calving and 2, 4 and 8 weeks post-calving. Liver biopsy samples were collected from all animals at drying off and 4 weeks post-calving. Live weight changed with time, but there was no effect of treatment (P>0.05), whereas cows receiving IB had the lowest mean body condition score and DB the highest (P<0.05). There was no effect of treatment on post-partum DM intake, milk yield or milk fat concentration (P>0.05) with mean values of 21.6 kg/day, 39.6 kg/day and 40.4 g/kg, respectively. Cows receiving IB had a higher plasma vitamin B12 concentration than those receiving any of the other treatments (P<0.001), but there was no effect (P>0.05) of treatment on homocysteine or succinate concentrations, although mean plasma methylmalonic acid concentrations were lower (P=0.019) for cows receiving IB than for Control cows. Plasma β-hydroxybutyrate concentrations increased sharply at calving followed by a decline, but there was no effect of treatment. Similarly, there was no effect (P>0.05) of treatment on plasma non-esterified fatty acids or glucose. Whole tract digestibility of DM and fibre measured at week 7 of lactation were similar between treatments, and there was little effect of treatment on the milk fatty acid profile except for C15:0, which was lower in cows receiving DC than IB (P<0.05). It is concluded that a basal dietary concentration of 0.21 mg Co/kg DM is sufficient to meet the requirements of high yielding dairy cows during the transition period, and there is little benefit from additional Co or vitamin B12.
The interval from calving to first ovulation is a major factor affecting reproductive and productive efficiency in beef cows. While this interval is affected by pre- and post-partum nutrition, the maternal-offspring bond is generally considered to be the major cause of delayed ovulation in beef cows. The endocrine and physiological mechanisms by which these factors either singularly or interactively control the duration of the post-partum anovulatory period are not well established, although they most likely involve the regulation of pulsatile LH release. The present study sought to examine the interactive effects of pre- and post-partum nutrition on LH secretion and follicle wave dynamics following acute calf isolation and once-a-day suckling (restricted access), after emergence of the fourth follicular wave post partum.
The prolonged interval from calving to first ovulation in beef cows is primarily due to the suckling-mediated inhibition of pulsatile LH release. Undernutrition both before and after calving also suppresses LH release, reduces ovarian follicular growth and delays ovulation. The interactive effects of these factors on the interval from calving to first ovulation in beef cows were quantified by studying the incidence of ovulation, following acute calf isolation and once-a-day suckling (restricted access), after emergence of the fourth follicular wave post partum in cows in differing body condition at calving and offered low or high planes of nutrition after calving.
The experiment was a 2 x 2 x 2 factorial design, in which the factors were body condition score at calving (Low v. Moderate), feeding level after calving (0.6 v. 1.0 MJ ME/d/kg M0.75), and restricted (once-a-day) v. ad libitum access and suckling. The experiment, duplicated at each of the four participating sites, involved 16 Simmental, 16 Sarda, 16 Brown Swiss and 16 Hereford x Friesian multi-parous cows. Follicle growth was monitored daily from day 21 post partum until the earlier of second ovulation or Day 90 post partum using transrectal ovarian ultrasonography.
There is anecdotal evidence that certain sheep breeds, reared in a particular way, produce unusual or characteristic tastes in cooked meat. Such effects could be linked to differences in meat fatty acid composition associated with the consumption of different diets. This study investigated eating quality and fat composition in 4 distinctively different breed x feeding system groups.
Four groups of 20 ram lambs were obtained as follows: Pure Soays (SO) finished off grass in April from commercial breeders; Pure Welsh Mountain (WM) finished off upland grass in October from ADAS Pwllpeiran; Suffolk x Mules from Harper Adams College finished off concentrates (grains) (SC) in April; and Suffolk x mules from the same source finished off grass (SG) in May. The animals were transported to Langford where they were slaughtered in Bristol University's abattoir.
Background: Selective amygdalohippocampectomy (SAH) is a surgical option in well-selected cases of pediatric medically refractory temporal lobe epilepsy (TLE). The objective of this study was to compare the surgical outcome and the rate of reoperation for ongoing or recurrent seizures between SAH and anterior temporal lobectomy (ATL) in pediatric TLE. Methods: Retrospective review of 78 pediatric intractable TLE patients referred to the Comprehensive Epilepsy Program at our institution between 1988 and 2015 treated initially with either a trans-middle temporal gyrus SAH (19) or ATL (59). Patients underwent baseline long-term video electroencephalography and 1.5-Tesla MRI. Neuropsychological testing was performed preoperatively and 12-months postoperatively (including reoperations). Results: The mean follow-up was 64 months (range, 12-186 months). The average age at initial surgery was 10.6±5 years with an average delay of 5.7±4 years between seizure onset and surgery. Ultimately 78% were seizure-free (61/78) at most recent follow-up. Seizure freedom after initial surgical treatment was achieved in 81% of patients who underwent ATL (48 patients) versus 42% in SAH (8 patients; p<0.001). Of patients with ongoing disabling seizures following SAH, reoperation (ATL) was offered in 8 resulting in seizure freedom in 63%, without interval neuropsychological decline. Conclusions: SAH amongst well-selected pediatric TLE results in significantly worse seizure control compared with ATL.
Considered as a less hazardous piezoelectric material, potassium sodium niobate (KNN) has been in the fore of the search for replacement of lead (Pb) zirconate titanate for piezoelectrics applications. Here, we challenge the environmental credentials of KNN due to the presence of ~60 wt% Nb2O5, a substance much less toxic to humans than Pb oxide, but whose mining and extraction cause significant environmental damage.
The Southern Hemisphere VLBI Experiment (SHEVE) program is aimed at producing high-resolution images of southern radio sources. The radio telescopes of the present SHEVE array are described below and some recent results presented.
During 1985-1987 Celestial Mechanics has been intensively developed in all its branches embracing physical bases, mathematical aspects, computational techniques and astronomical objectives. Commission 7 has organized three IAU conferences: Symposium No. 114 “Relativity in Celestial Mechanics and Astrometry” (Leningrad, May 1985), Colloquium No. 96 “The Few Body Problem” (Turku, June 1987) and Topical Session “Resonances in the Solar System” of the X-th European Regional Astronomy Meeting (Prague, August 1987). Members of the commission have broadly participated in the NATO Advanced Study Institute “Long-Term Dynamical Behaviour of Natural and Artificial N-Body Systems” (Cortina d’Ampezzo, August 1987) and some other international and regional conferences. Prospects of the actual celestial mechanics investigations have been discussed at a session of Commission 7 at the XIX-th IAU General Assembly (New Delhi, November 1985). Three papers dealing with the unsolved problems of celestial mechanics were primarily addressed to the rising generation of celestial mechanicians (V. A. Brumberg and J. Kovalevsky, CM. 39, 133, 1986; P.K. Seidelmann, CM. 39, 141, 1986).
Several extragalactic HI surveys using a λ21 cm 13-beam focal plane array will begin in early 1997 using the Parkes 64 m telescope. These surveys are designed to detect efficiently nearby galaxies that have failed to be identified optically because of low optical surface brightness or high optical extinction. We discuss scientific and technical aspects of the multibeam receiver, including astronomical objectives, feed, receiver and correlator design and data acquisition. A comparison with other telescopes shows that the Parkes multibeam receiver has significant speed advantages for any large-area λ21 cm galaxy survey in the velocity range range 0–14000 km s−1.
PKS 1830–211 is the strongest known radio gravitational lens by almost an order of magnitude and has the potential to provide a measurement of H0, provided the lensing system can be parameterized. Attempts to identify optical counterparts, to measure redshifts, have so far proved unsuccessful and this has lead to radio and millimetre spectral line observations. We present our discovery of an absorption system at z = 0.19. A brief description is also made of our ATCA observations to measure the lensing time delay for this source.
In light of increasing global protein prices and with the need to reduce environmental impact of contemporary systems of milk production, the current review seeks to assess the feasibility of reducing levels of dietary CP in dairy cow diets. At CP levels between 140 and 220 g/kg DM there is a strong positive relationship between CP concentration and dry matter intake (DMI). However, such effects are modest and reductions in DMI when dietary CP is below 180 g/kg DM can be at least partially offset by improving the digestibility and amino acid profile of the undegradable protein (UDP) component of the diet or by increasing rumen fermentable energy. Level and balance of intestinally absorbable amino acids, in particular methionine and lysine, may become limiting at lower CP concentrations. In general the amino acid composition of microbial protein is superior to that of UDP, so that dietary strategies that aim to promote microbial protein synthesis in the rumen may go some way to correcting for amino acid imbalances in low CP diets. For example, reducing the level of NDF, while increasing the proportion of starch, can lead to improvements in nitrogen (N) utilisation as great as that achieved by reducing dietary CP to below 150 g/kg. A systematic review and meta-analysis of responses to rumen protected forms of methionine and lysine was conducted for early/mid lactation cows fed diets containing ⩽150 g CP/kg DM. This analysis revealed a small but significant (P=0.002) increase in milk protein yield when cows were supplemented with these rumen protected amino acids. Variation in milk and milk protein yield responses between studies was not random but due to differences in diet composition between studies. Cows fed low CP diets can respond to supplemental methionine and lysine so long as DMI is not limiting, metabolisable protein (MP) is not grossly deficient and other amino acids such as histidine and leucine do not become rate limiting. Whereas excess dietary protein can impair reproduction and can contribute to lameness, there is no evidence to indicate that reducing dietary CP levels to around 140 to 150 g CP/kg DM will have any detrimental effect on either cow fertility or health. Contemporary models that estimate MP requirements of dairy cows may require refinement and further validation in order to predict responses with low CP diets.
Resistance tube closure welds, referred to as pinch welds, are used to reliably seal small stainless steel tubing . The quality of the bond is dependent upon, among other factors, the cleanliness of the tube bore. Post weld inspections are therefore desired as process control procedures. In previous studies, ultrasonics was shown to have considerable promise in this application. Thomas et al.  demonstrated that pattern recognition algorithms could be applied to the ultrasonic signals transmitted through the tubes to produce a correct classification of good and bad welds in several different sets of samples. The algorithms were somewhat dependent on the material from which the samples were fabricated, but all showed a good deal of commonality. In a parallel study, Rehbein et al.  examined, from a more mechanistic point of view, sets of tubes fabricated at the same time. They observed that gross disbonds could be easily detected from changes in signals either reflected from or transmitted through the bond line. When such disbonds were not present, they observed that signals doubly transmitted through the interface (i.e., the back surface echo) showed a trend to lower values as the bond quality decreased. This paper describes the sequel to that study, having the objective of developing a quantitative understanding of the interaction of the ultrasound with the pinch welds.
The promise of conducting polymers as fast response nonlinear optical materials has been recently emphasized [1,3]. Polymers such as polyacetylene, polythiophene and the soluble (and processible) poly(3-alkylthienylenes) contain a high density of x-electrons, and they are known to exhibit photoinduced absorption and photoinduced bleaching, indicating major shifts of oscillator strength upon photoexcitation [2,4]. For polyacetylene, these nonlinear effects have been studied in detail in the picosecond [5a,b] and sub-picosecond [5c] time regime and correlated with the photoproduction of charge carriers through fast photoconductivity measurements . The data have demonstrated ultra-fast response with nonlinear shifts in oscillator strength occurring at times of the order of 10-13 seconds. These resonant nonlinear optical properties are intrinsic; they originate from the nonlinearity of the self-localized photoexcitations  which characterize this class of polymers: solitons, polarons and bipolarons .
We report observations of interfacial structure and consequences for layer synthesis modes in mesotaxial Si/CoSi2/Si structures, as deduced from high resolution transmission electron microscopy (HRTEM). It is argued that relative crystal misalignments arising from the lattice parameter mismatch between the Si and CoSi2 may render classic rigid shift measurements of interfacial structure inaccurate. An alternative method for determining interfacial structure at threedimensional precipitates by analyzing crystal stacking sequences is demonstrated.
An experimental high resolution image of a grain boundary has been compared with images simulated from atomic structures calculated by two theoretical methods. Some of the techniques used in the analysis of the images are presented. A good agreement is found between each theory and the experiment, confirming the validity of calculations of such a boundary.