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Successful Treatment of Primary Orthostatic Tremor Using Perampanel
Background: Primary orthostatic tremor (POT) remains a therapeutic conundrum. Various medication classes have been tried, yielding modest results at best.
Case Report: A 62-year-old female with a 13-year history of POT, refractory to clonazepam up to 20 mg/day, was treated with perampanel 1–2 mg/day. She reported 90% subjective symptomatic improvement.
Discussion: This case highlights the potential for use of perampanel, a novel AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor antagonist for the treatment of POT. There has been one prior report citing its use for POT with complete resolution of symptoms. We encourage further studies to highlight its efficacy for POT
Neonatal White Matter Maturation Is Associated With Infant Language Development
Background:
While neonates have no sophisticated language skills, the neural basis for acquiring this function is assumed to already be present at birth. Receptive language is measurable by 6 months of age and meaningful speech production by 10-18 months of age. Fiber tracts supporting language processing include the corpus callosum (CC), which plays a key role in the hemispheric lateralization of language; the left arcuate fasciculus (AF), which is associated with syntactic processing; and the right AF, which plays a role in prosody and semantics. We examined if neonatal maturation of these fiber tracts is associated with receptive language development at 12 months of age.
Methods:
Diffusion-weighted imaging (DWI) was performed in 86 infants at 26.6 ± 12.2 days post-birth. Receptive language was assessed via the MacArthur-Bates Communicative Development Inventory at 12 months of age. Tract-based fractional anisotropy (FA) was determined using the NA-MIC atlas-based fiber analysis toolkit. Associations between neonatal regional FA, adjusted for gestational age at birth and age at scan, and language development at 12 months of age were tested using ANOVA models.
Results:
After multiple comparisons correction, higher neonatal FA was positively associated with receptive language at 12 months of age within the genu (p < 0.001), rostrum (p < 0.001), and tapetum (p < 0.001) of the CC and the left fronto-parietal AF (p = 0.008). No significant clusters were found in the right AF.
Conclusion:
Microstructural development of the CC and the AF in the newborn is associated with receptive language at 12 months of age, demonstrating that interindividual variation in white matter microstructure is relevant for later language development, and indicating that the neural foundation for language processing is laid well ahead of the majority of language acquisition. This suggests that some origins of impaired language development may lie in the intrauterine and potentially neonatal period of life. Understanding how interindividual differences in neonatal brain maturity relate to the acquisition of function, particularly during early development when the brain is in an unparalleled window of plasticity, is key to identifying opportunities for harnessing neuroplasticity in health and disease
Trace Element Abundances in an Unusual Hibonite-Perovskite Refractory Inclusion from Allende
Calcium-aluminum-rich refractory inclusions (CAIs) are thought to be the first-formed solids in the Solar protoplanetary disk and can provide information about the earliest Solar System processes (e.g., [1]). A hibonite-perovskitebearing CAI from the Allende CV3 chondrite (SHAL, [2]) contains a single of 500 micrometers hibonite grain and coarse-grained perovskite. The mineralogy and oxygen isotopic composition of this CAI shows similarities with FUN inclusions, especially HAL [2]. Here we present trace element abundances in SHAL
Toric Calabi-Yau supermanifolds and mirror symmetry
We study mirror symmetry of supermanifolds constructed as fermionic
extensions of compact toric varieties. We mainly discuss the case where the
linear sigma A-model contains as many fermionic fields as there are U(1)
factors in the gauge group. In the mirror super-Landau-Ginzburg B-model, focus
is on the bosonic structure obtained after integrating out all the fermions.
Our key observation is that there is a relation between the super-Calabi-Yau
conditions of the A-model and quasi-homogeneity of the B-model, and that the
degree of the associated superpotential in the B-model is given in terms of the
determinant of the fermion charge matrix of the A-model.Comment: 20 pages, v2: references adde
Sex- and tissue-specific Bkm(GATA)-binding protein in the germ cells of heterogametic sex
The ZZ male/ZW female system of sex determination (female heterogamety) is found in snakes and birds whereas XY male/XX female system of sex determination (male heterogamety) operates in mammals including humans. The W and Y chromosomes are largely heterochromatic and undergo cycles of condensation and decondensation in the germ cells of ovary and testis, respectively, whereas they remain highly condensed and transcriptionally inactive in all somatic cells. Both chromosomes have enriched stretches of GATA repeats along their entire length (which is identified as banded krait minor satellite DNA and called Bkm) that are highly conserved through widely separated orders of eukaryotes. Here we report the existence of a factor, which specifically binds to Bkm, in the germ cells of the heterogametic sex (ovary in female heterogamety and testis in male heterogamety) where decondensation (activation) of the W and Y chromosomes, respectively, occurs; it has been purified as a polypeptide of 57.5 kDa from the rat snake ovary and designated as Bkm-binding protein (BBP) by virtue of its binding to GATA repeats of Bkm. Such a sex- and tissue-specific BBP is also present in the ovary of other species of snakes and in the testis of mouse and human where the Y chromosome is highly decondensed. We suggest that GATA repeats of Bkm brings about a coordinated decondensation of the W and Y sex chromosomes in the germ cells of the heterogametic sex in response to BBP which may serve as a "switch" for the activation of the genes present on the W and Y chromosomes
Relationship Between Maternal Distress with Fetus Growth Rate: Mediator Role of Heart Rate
On Local Calabi-Yau Supermanifolds and Their Mirrors
We use local mirror symmetry to study a class of local Calabi-Yau
super-manifolds with bosonic sub-variety V_b having a vanishing first Chern
class. Solving the usual super- CY condition, requiring the equality of the
total U(1) gauge charges of bosons \Phi_{b} and the ghost like fields \Psi_{f}
one \sum_{b}q_{b}=\sum_{f}Q_{f}, as \sum_{b}q_{b}=0 and \sum_{f}Q_{f}=0,
several examples are studied and explicit results are given for local A_{r}
super-geometries. A comment on purely fermionic super-CY manifolds
corresponding to the special case where q_{b}=0, \forall b and \sum_{f}Q_{f}=0
is also made.\bigskipComment: 17 page
Dating Howardite Melt Clasts: Evidence for an Extended Vestan Bombardment?
Howardites are polymict breccias that, together with eucrites and diogenites (HED), likely originate from the vestan surface (regolith/ megaregolith), and display a heterogeneous distribution of eucritic and diogenitic material. Melt clasts are also present alongside other regolithic features within howardites, and are noteworthy for their compositional variability and appearance. Melt clasts formed by impact events provide a snapshot of the timings and conditions of surface gardening and bombardment on the vestan surface. By dating such clasts, we aim to better constrain the timings of impact events on Vesta, and to establish whether the impact flux in the asteroid belt was similar to that on the Moon. As the Moon is used as the basis for characterising impact models of the inner solar system, it is necessary to verify that apparent wide-scale events are seen in other planetary bodies. In particular, the observed clustering of Apollo melt clast ages between 3.8-4.0 Ga has led to two hypotheses: 1) The Moon was subjected to a sudden event - 'Lunar Cataclysm' or period of 'Late Heavy Bombardment' (LHB), 2) The age cluster represents the end of an epoch of declining bombardment or 'Heavy Bombardment. No consensus has emerged regarding one or other hypothesis. We are testing these hypotheses by seeking evidence for such events in materials other than those derived from the Moon
Impact History on Vesta: Petrographic, Compositional and Future Chronological Studies of Melt Clasts in Howardites
Howardite meteorites are polymict breccias composed mainly of eucritic and diogenitic material that likely originate from the surface of the Asteroid 4 Vesta. They can be separated into two subtypes: Regolithic, which represent the lithified remains of the active vestan regolith; Fragmental, which represent simpler polymict breccias. Amongst the regolithic features observed in the former, melt clasts are particularly striking for their appearance and compositional variability. They range from glassy spherules to finely crystalline (i.e., devitrified) clasts, and clasts containing only relict mineral grains to those containing only phenocrysts. Glasses can be separated into compositional sub-types including those with low FeO/MgO ratios (less than 5) -low alkali glasses, K-rich (K2O greater than 0.2 wt.%), Na-rich (Na2O greater than 0.6 wt.%) and CaO-rich, and those with high FeO/MgO ratios (greater than 10). There is also a distinction to be made between primary volcanic melt clasts and those produced by impacts. While suggested that a lack of chemical homogeneity among their studied melt clasts ruled out a primary volcanic origin, the low siderophile element contents observed in such clasts suggest less compositional influence from impactors than commonly assumed. Studying the chronology of the impact melt clasts in howardites can help us to better determine the timing of impact events on Vesta and the asteroid belt. In this research, we are launching an investigation into the petrology, composition (major/trace element and noble gas) and chronology of melt clasts in howardites. We have selected a set of howardites known to contain large quantities of melt clasts, and have begun the petrological and compositional studies of these materials. Once the melt clasts have been fully classified, we aim to perform chronological studies of individual clasts using both the Ar-40/Ar-39 and Pb-Pb chronometers, as well as determine the noble gas components present. Of particular note, the study will take advantage of the laser ablation techniques associated with the noble gas facilities at ASU, which will allow high-resolution, in-situ analysis of individual clasts. The broader aim of this work is to ascertain whether the impact flux in the region of the asteroid belt was similar to that on the Moon. Our understanding of impact events in the inner Solar System relies heavily on our analyses of lunar meteorites and returned samples, and there is currently some debate regarding whether there was a "Lunar Cataclysm" event around approx. 3.9 Ga, or the end of an epoch of "Late Heavy Bombardment" (LHB) at this time. New and more comprehensive constraints on howardite melt clast ages may help determine whether the asteroid belt experienced such a cataclysm or LHB
Numerical computation of electric field and potential along silicone rubber insulators under contaminated and dry band conditions
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