We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Background: Adult thalamic gliomas (ATGs) present a surgical challenge given their depth and proximity to eloquent brain regions.Though a relative abundance of literature has been published regarding the surgical management of thalamic lesions in pediatric patients, a scarce amount exists dedicated to adult populations. Methods: Literature regarding surgical management of thalamic gliomas in adult patients was reviewed according to the PRISMA guidelines. Fours databases were searched with keywords “‘thalamic glioma’ AND ‘surgical intervention’ OR ‘thalamic glioma’ AND ‘surgical treatment’” in July 2021 for articles assessing surgical techniques of ATG resection. Results: The mean age of adult undergoing surgical management was 33.57 years with a median preoperative KPS of 72.15. Among the 507 cases, several surgical approaches were utilized. Transcortical approaches were most frequently used accounting for 37.8% of all cases followed by transventricular (23.8%), transcallosal (22.8%), and trans-sylvian transinsular (2.92%). Conclusions: Studies in this review agree that decreased age, low grade glioma, increased KPS, and increased duration of symptoms are positive prognostic factors. Greater degree of resection provides a positive survival benefit, and transcortical approaches appear to carry a greater overall survival. Stratified guidelines could pose an overall advantage to surgical success when making decisions on treatment approach.
The Gaia-ESO Survey (GES) is a large public spectroscopic survey that has collected spectra of about 100,000 stars. The survey provides not only the reduced spectra, but also the radial velocities, stellar parameters and surface abundances resulting from the analysis of the spectra. We present the work of the groups that analysed the spectra of the hottest stars in that Survey. The large temperature range that is covered (Teff = 7,000 to 50,000 K) requires the use of different analysis codes by the different groups. Eight groups each analysed part of the data, with significant overlap that allowed cross-checks. In total 17,693 spectra of 6,462 stars were analysed, most of them in 37 open star clusters. The homogenisation of all this information led to stellar parameters for 5,584 stars. Abundances for at least one of the elements He, C, N, O, Ne, Mg, Al, Si and Sc were determined for 292 stars. The GES hot star data, as well as the Survey data in general, will be of considerable use in future studies of stellar evolution and open clusters.
Botanical residues recovered from excavations in the Southeast Marketplace of Piedras Negras provide information about the healing and medical activities of the site's Classic period (a.d. 350–900) inhabitants, and point towards the intersection between commerce and medicine for the ancient Maya. The plants were likely exchanged at the market then used on-site for the purposes of healing. The botanical remains are complemented by both architectural and bioarchaeological evidence for healing at this locus, including a high concentration of sweatbaths and evidence for palliative tooth extraction. With the aid of ethnohistory, we identify health care practices potentially associated with the plant remains. However, we expand on basic understandings of “healing” with a critical look at how some medicinal plants may have been ritually invoked, even when never directly ingested or applied topically.
Although investigation have demonstrated that stimulants are effective medication for the treatment of the symptoms on the ADHD, a commonly described but quite slightly studied side effect of this type of medication, is the effect on the emotional expression of patients.
Objectives
evaluate the effect of the treatment with Methylphenidate on the affective/emotional expression in children diagnosed with ADHD.
Methods
It's a descriptive study of several cases series, from a center and about a unique group, where 'n” will be 15 children diagnosed with ADHD at the University Hospital, who were required beginning treatment with methylphenidate, with a daily dose of at least 0,3mg/Kg. In this study it will be evaluated the emotional expression of the group, according to the scale Expression and Emotion Scale for Children (EESC) making a comparison between the previous moment to the treatment and a subsequent month from its beginning.
Results
The evaluation of the total result of the EESC conducted by the parent didn't show statistically significant differences between scores previously of the treatment and results after a month with it. The dominions (positive emotions, emotional flatness and emotional lability) didn't show differences between both periods of time, nevertheless, the positive emotions showed a tendency of reduction more showy than the rest, without getting to be statistically significant (p=0.0638).
Conclusion
Statistically there haven't been significant changes in the emotional expression of the children caused by the treatment with methylphenidate. Nevertheless, the data show that there is a tendency to an improvement in it.
This study describes epidemiological trends for acute rotavirus gastroenteritis (RVGE) in Belgium in children aged ⩽5 years during the period June 2007 to May 2014 after the introduction of routine rotavirus (RV) vaccination. This period encompassed the switch from lyophilized to the liquid formulation of Rotarix™ (GlaxoSmithKline, Belgium) in August 2011. Uptake of RV vaccine remained consistently high throughout the study period with Rotarix the brand most often used. RV was present in 9% (1139/12 511) of hospitalized cases with acute gastroenteritis included in the study. Epidemiological trends for hospital admissions for RVGE remained consistent throughout the study period, with no evidence of any change associated with the switch from lyophilized to liquid formulation of Rotarix. This suggests both formulations perform similarly, with the liquid formulation not inferior regarding ability to reduce hospital admissions for acute RVGE in children aged ⩽5 years. A strong seasonal effect was observed with most RVGE occurring in the winter months but with some variability in intensity, with highest incidence found in those aged 6–24 months. The main observation was the decreased number of hospital admissions for RVGE in Belgium that occurred during winter 2013/2014.
The B fields in OB stars (BOB) survey is an ESO large programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. As of July 2014, a total of 98 objects were observed over 20 nights with FORS2 and HARPSpol. Our preliminary results indicate that the fraction of magnetic OB stars with an organised, detectable field is low. This conclusion, now independently reached by two different surveys, has profound implications for any theoretical model attempting to explain the field formation in these objects. We discuss in this contribution some important issues addressed by our observations (e.g., the lower bound of the field strength) and the discovery of some remarkable objects.
We present the results of an abundance analysis of two magnetic B-type stars in the Orion Nebula Cluster that support the lack of a direct relationship between the existence of a magnetic field and a nitrogen excess in the photosphere.
Studying exoplanets with their parent stars is crucial to understand their population, formation and history. We review some of the key questions regarding their evolution with particular emphasis on giant gaseous exoplanets orbiting close to solar-type stars. For masses above that of Saturn, transiting exoplanets have large radii indicative of the presence of a massive hydrogen-helium envelope. Theoretical models show that this envelope progressively cools and contracts with a rate of energy loss inversely proportional to the planetary age. The combined measurement of planetary mass, radius and a constraint on the (stellar) age enables a global determination of the amount of heavy elements present in the planet interior. The comparison with stellar metallicity shows a correlation between the two, indicating that accretion played a crucial role in the formation of planets. The dynamical evolution of exoplanets also depends on the properties of the central star. We show that the lack of massive giant planets and brown dwarfs in close orbit around G-dwarfs and their presence around F-dwarfs are probably tied to the different properties of dissipation in the stellar interiors. Both the evolution and the composition of stars and planets are intimately linked.
Within Silicon Carbide Junction Field Effect Transistor (SiC-JFET) model, body diode is not extensively studied and almost under-researched. Body diode remains a complex device to study particularly during switching transients. In this paper, the JFET body diode is experimentally demonstrated to be a power PiN diode. Finite element method model based on the device geometry and SiC material is used to accurately simulate this diode. Accurate simulations are necessary for analysis and verification purposes. Simulation relies on component models and associated parameters. The paper focuses on a step-by-step extraction procedure for design parameters of the SiC-JFET body diode. A comparative study between experimental data and simulation results is given to validate the device model and associate parameters.
This paper focuses on the modelling of a SiC-JFET. The novelty aspect is the dependence on temperature. An accurate model has been used in a previous work and an identification procedure for the main model parameters has been demonstrated. Readers have asked for a more advanced SiC JFET temperature-dependent model. A limitation of the current model versus temperature is verified and explained in order to introduce the necessity of a new temperature dependence model. A more advanced model is then considered and a comparative study between experiment and simulation of the device is established. The characteristics of three SiC JFETs devices are considered from experimental and simulation point-of-view. Simulations results clearly replicate the experimental data at different temperatures and a new validity approach, namely validity maps, is proposed. Validity domains are discussed.
We present preliminary results of a 4-month campaign carried out in the framework of the Mons project, where time-resolved Hα observations are used to study the wind and circumstellar properties of a number of OB stars.
We present the results from the spectroscopic follow-up of WR140 (WC7 + O4-5) during its last periastron passage in january 2009. This object is known as the archetype of colliding wind binaries and has a relatively large period (≃8 years) and eccentricity (≃0.89). We provide updated values for the orbital parameters, new estimates for the WR and O star masses and new constraints on the mass-loss rates.
The present study investigated the effects of maternal plasma iodine concentration on twin- and triplet-born lamb plasma thyroid hormone concentrations, rectal temperature and maximal heat production. On pregnancy day 68 (P68), 16 twin- and 14 triplet-bearing ewes were randomly chosen from ewes that were injected intramuscularly with 1·5 ml of iodized peanut oil and ewes that were not. Selected ewes were grazed on ad libitum pasture from P68 until parturition. After parturition, lamb blood samples were collected within 5 min of birth and at 3, 12 and 24–36 h after birth. Lamb rectal temperatures were measured within 5 min of birth and at 1, 3 and 12 h after birth. Lamb body weight, crown–rump length and thoracic-girth circumference were recorded at 3 h of age, and the capability of the lamb to produce heat at 24–36 h of age was measured using indirect open-circuit calorimetry. Maternal iodine supplementation successfully increased plasma iodine concentrations of twin- and triplet-bearing ewes throughout pregnancy, but had no effect on the rectal temperature, thyroid hormone concentration and maximal heat production of twin- or triplet-born lambs. Compared with twin-born lambs, triplet-born lambs had lower birth weights, rectal temperatures and plasma T4 and T3 concentrations within 5 min of birth. Overall, under the conditions of the present study, maternal iodine supplementation offered no benefit in improving lamb heat production.
During the five years of the mission, the Gaia spectrograph, the Radial Velocity
Spectrometer (RVS) will repeatedly survey the celestial sphere down to magnitude
V ~ 17–18. This talk presents: (i) the system which is currently developed within
the Gaia Data Processing and Analysis Consortium (DPAC) to reduce and calibrate the
spectra and to derive the radial and rotational velocities, (ii) the RVS expected
performances and (iii) scientific returns.
Silicon carbide junction field effect transistor (SiC-JFETs) is a mature power switch newly applied in several industrial applications. SiC-JFETs are often simulated by Spice model in order to predict their electrical behaviour. Although such a model provides sufficient accuracy for some applications, this paper shows that it presents serious shortcomings in terms of the neglect of the body diode model, among many others in circuit model topology. Simulation correction is then mandatory and a new model should be proposed. Moreover, this paper gives an enhanced model based on experimental dc and ac data. New devices are added to the conventional circuit model giving accurate static and dynamic behaviour, an effect not accounted in the Spice model. The improved model is implemented into VHDL-AMS language and steady-state dynamic and transient responses are simulated for many SiC-VJFETs samples. Very simple and reliable optimization algorithm based on the optimization of a cost function is proposed to extract the JFET model parameters. The obtained parameters are verified by comparing errors between simulations results and experimental data.
The current study investigated the effect of offering concentrate supplement to ewes in late pregnancy on twin- and triplet-born lamb heat production at 24–36 h old and performance from birth until lactation day 94 (L94). Twin- (n=40) and triplet-bearing (n=28) ewes were grazed on a 60 mm sward height from day 70 of pregnancy (P70) until L94. From P100, half of the ewes from each litter size were offered 400 g/ewe/day of concentrate sheep pellets. Ewe liveweight and body condition were recorded on P50, 100, 130, 135 and 140. Ewe blood samples were also collected on P130, 135 and 140, and ewe herbage intake was estimated from P133–136 using the n-alkane method. Lamb measurements included liveweight and body size at birth, production of heat using indirect open-circuit calorimetry at 24–36 h old and liveweight at L94. Blood samples were also collected from lambs at 24–36 h old and directly before and after calorimetry measurements. While estimates of ewe herbage intake suggested that substitution of herbage for concentrate did not occur, offering concentrate supplement failed to improve ewe liveweight gain, or birth weight of lambs. Offering concentrate supplement, however, did have a positive effect (P<0·05) on the maximal amount of heat a triplet-born lamb can produce on a per kg of body weight basis (concentrate 21±1·3 W/kg, non-concentrate 17±0·6 W/kg). It also had a positive effect (P<0·05) on lamb square-root-transformed plasma gamma-glutamyl transferase (GGT) concentrations, an indicator of colostrum uptake (concentrate 46±3·1 U/l, non-concentrate 38±2·9 U/l). Irrespective of lamb birth rank, offering concentrate supplement had a positive effect (P<0·01) on liveweight gain per day from birth until L94 (concentrate 261±5·7 g/day, non-concentrate 239±5·8 g/day), although there was no effect on the total weight of lamb reared/ewe. Supplementation with concentrate resulted in triplet-born lambs that produced more heat which may have positive effects on the ability of the newborn lamb to deal with cold stress and potentially its survival. Offering concentrate supplement also produced greater lamb growth in twin- and triplet-born lambs.
The Hartree-Fock theory of fluctuations leading to simple formulae for configuration probabilities is used in a Detailed Configuration Accounting calculation of opacity in the case of an iron plasma. A direct Detailed Term Accounting method is also applied. The correlations of subshell occupation numbers, which are accounted for in the HF theory, show small effect on the theoretical spectrum corresponding to conditions of a recent measurement.
We present the results of the continuation of our magnetic survey with FORS 1 at the VLT of a sample of B-type stars consisting of confirmed or candidate β Cephei stars and Slowly Pulsating B stars. Roughly one third of the studied β Cephei stars have detected magnetic fields. The fraction of magnetic Slowly Pulsating B and candidate Slowly Pulsating B stars is found to be higher, up to 50%. We find that the domains of magnetic and non-magnetic pulsating stars in the H-R diagram largely overlap, and no clear picture emerges as to the possible evolution of the magnetic field across the main sequence.