356 research outputs found
A note on bosonic open strings in constant B field
We sketch the main steps of old covariant quantization of bosonic open
strings in a constant field background. We comment on its space-time
symmetries and the induced effective metric. The low-energy spectrum is
evaluated and the appearance of a new non-commutative gauge symmetry is
addressed.Comment: 13 pages, Latex, important comments added, to appear in PR
A Biallelic Truncating Variant in the TPR Domain of GEMIN5 Associated with Intellectual Disability and Cerebral Atrophy.
GEMIN5 is a multifunctional RNA-binding protein required for the assembly of survival motor neurons. Several bi-allelic truncating and missense variants in this gene are reported to cause a neurodevelopmental disorder characterized by cerebellar atrophy, intellectual disability (ID), and motor dysfunction. Whole exome sequencing of a Pakistani consanguineous family with three brothers affected by ID, cerebral atrophy, mobility, and speech impairment revealed a novel homozygous 3bp-deletion NM_015465.5:c.3162_3164del that leads to the loss of NM_015465.5 (NP_056280.2):p. (Asp1054_Ala1055delinsGlu) amino acid in one of the α-helixes of the tetratricopeptide repeats of GEMIN5. In silico 3D representations of the GEMIN5 dimerization domain show that this variant likely affects the orientation of the downstream sidechains out of the helix axis, which would affect the packing with neighboring helices. The phenotype of all affected siblings overlaps well with previously reported patients, suggesting that NM_015465.5: c.3162_3164del (NP_056280.2):p. (Asp1054_Ala1055delinsGlu) is a novel GEMIN5 pathogenic variant. Overall, our data expands the molecular and clinical phenotype of the recently described neurodevelopmental disorder with cerebellar atrophy and motor dysfunction (NEDCAM) syndrome
Tensile properties of Poly Lactic Acid (PLA)–Tungsten Trioxide (WO3) nano composites for 3D printing process
Poly Lactic Acid (PLA) is one of the most crucial aliphatic polyesters which is considered as one of the favourable options in environmentally friendly thermoplastic polymers since it could be biodegraded in certain conditions. PLA has been extensively used in the packaging, electronic industries, and household applications. As a result, the improvement of mechanical properties of PLA is necessary, which can be achieved through heat resistant materials such as Tungsten trioxide (WO3). The objective of this research was to investigate the tensile properties of PLA-WO3. The 3D printing process was employed to fabricate PLA-WO3 (3wt% WO3) and Neat PLA (control sample). The tensile test was conducted to investigate the effect of WO3 to the PLA. The results show that the tensile properties of PLA-WO3 were improved up to 75% as compared to Neat PLA. This result shows positive indication to the PLA-WO3 for many industrial applications
Live Birth of a Healthy Child in a Couple with Identical mtDNA Carrying a Pathogenic c.471_477delTTTAAAAinsG Variant in the MOCS2 Gene.
Molybdenum cofactor deficiency type B (MOCODB; #252160) is an autosomal recessive metabolic disorder that has only been described in 37 affected patients. In this report, we describe the presence of an in-frame homozygous variant (c.471_477delTTTAAAAinsG) in the MOCS2 gene in an affected child, diagnosed with Ohtahara syndrome according to the clinical manifestations. The analysis of the three-dimensional structure of the protein and the amino acid substitutions suggested the pathogenicity of this mutation. To prevent transmitting this mutation to the next generation, we used preimplantation genetic testing for the monogenic disorders (PGT-M) protocol to select MOCS2 gene mutant-free embryos for transfer in an in vitro fertilization (IVF) program. As a result, a healthy child was born. Interestingly, both parents of the proband shared an identical mitochondrial (mt) DNA control region, assuming their close relationship and thus suggesting that both copies of the nuclear rare variant c.471_477delTTTAAAAinsG may have been transmitted from the same female ancestor. Our estimation of the a priori probability of meeting individuals with the same mtDNA haplotype confirms the assumption of a possible distant maternal relationship among the proband's direct relatives
Accurate and linear time pose estimation from points and lines
The final publication is available at link.springer.comThe Perspective-n-Point (PnP) problem seeks to estimate the pose of a calibrated camera from n 3Dto-2D point correspondences. There are situations, though, where PnP solutions are prone to fail because feature point correspondences cannot be reliably estimated (e.g. scenes with repetitive patterns or with low texture). In such
scenarios, one can still exploit alternative geometric entities, such as lines, yielding the so-called Perspective-n-Line (PnL) algorithms. Unfortunately, existing PnL solutions are not as accurate and efficient as their point-based
counterparts. In this paper we propose a novel approach to introduce 3D-to-2D line correspondences into a PnP formulation, allowing to simultaneously process points and lines. For this purpose we introduce an algebraic line error
that can be formulated as linear constraints on the line endpoints, even when these are not directly observable. These constraints can then be naturally integrated within the linear formulations of two state-of-the-art point-based algorithms,
the OPnP and the EPnP, allowing them to indistinctly handle points, lines, or a combination of them. Exhaustive experiments show that the proposed formulation brings remarkable boost in performance compared to only point or
only line based solutions, with a negligible computational overhead compared to the original OPnP and EPnP.Peer ReviewedPostprint (author's final draft
EFFECTS OF HIGH DIETARY CALCIUM AND LOW PHOSPHORUS ON URINARY SYSTEM OF BROILER CHICKS
The present study was carried out to investigate the effects of high dietary calcium and low phosphorus on urinary system of broiler chicks. A total of 90 (day-old) broiler chicks were divided into three equal groups A, B and C. The chicks were reared for 42 days on three experimental rations. Calcium:phosphorus ratio in the feed for groups A, B and C was maintained as 1:0.5 (control), 2:0.5 and 3:0.5, respectively. Various parameters studied included serum calcium and phosphorus concentrations, FCR, kidney:body weight ratio, and pathological examination of urinary system. The birds fed on high dietary calcium and low phosphorus revealed hypercalcaemia and hypophosphataemia in their sera. The FCR and mean kidney:body weight ratio of treatment groups was higher than the control group. The urinary system of the treated birds, in general, displayed inflammatory lesions, showing abnormalities of colour, size, shape and texture of kidneys and ureters. The ureters also showed occlusion and distention. The microscopic examination of the kidneys showing gross pathological lesions revealed common histopathological changes in glomeruli, tubular cells and interlobular veins
Human cerebrovascular contractile receptors are upregulated via a B-Raf/MEK/ERK-sensitive signaling pathway
<p>Abstract</p> <p>Background</p> <p>Cerebral ischemia results in a rapid increase in contractile cerebrovascular receptors, such as the 5-hydroxytryptamine type 1B (5-HT<sub>1B</sub>), angiotensin II type 1 (AT<sub>1</sub>), and endothelin type B (ET<sub>B</sub>) receptors, in the vessel walls within the ischemic region, which further impairs local blood flow and aggravates tissue damage. This receptor upregulation occurs via activation of the mitogen-activated protein kinase pathway. We therefore hypothesized an important role for B-Raf, the first signaling molecule in the pathway. To test our hypothesis, human cerebral arteries were incubated at 37°C for 48 h in the absence or presence of a B-Raf inhibitor: SB-386023 or SB-590885. Contractile properties were evaluated in a myograph and protein expression of the individual receptors and activated phosphorylated B-Raf (p-B-Raf) was evaluated immunohistochemically.</p> <p>Results</p> <p>5-HT<sub>1B</sub>, AT<sub>1</sub>, and ET<sub>B </sub>receptor-mediated contractions were significantly reduced by application of SB-590885, and to a smaller extent by SB-386023. A marked reduction in AT<sub>1 </sub>receptor immunoreactivity was observed after treatment with SB-590885. Treatment with SB-590885 and SB-386023 diminished the culture-induced increase of p-B-Raf immunoreactivity.</p> <p>Conclusions</p> <p>B-Raf signaling has a key function in the altered expression of vascular contractile receptors observed after organ culture. Therefore, specific targeting of B-Raf might be a novel approach to reduce tissue damage after cerebral ischemia by preventing the previously observed upregulation of contractile receptors in smooth muscle cells.</p
Novel C8orf37 mutations cause retinitis pigmentosa in consanguineous families of Pakistani origin
Purpose: To investigate the molecular basis of retinitis pigmentosa in two consanguineous families of Pakistani origin with multiple affected members. Methods: Homozygosity mapping and Sanger sequencing of candidate genes were performed in one family while the other was analyzed with whole exome next-generation sequencing. A minigene splicing assay was used to confirm the splicing defects. Results: In family MA48, a novel homozygous nucleotide substitution in C8orf37, c.244–2A>C, that disrupted the consensus splice acceptor site of exon 3 was found. The minigene splicing assay revealed that this mutation activated a cryptic splice site within exon 3, causing a 22 bp deletion in the transcript that is predicted to lead to a frameshift followed by premature protein truncation. In family MA13, a novel homozygous null mutation in C8orf37, c.555G>A, p.W185*, was identified. Both mutations segregated with the disease phenotype as expected in a recessive manner and were absent in 8,244 unrelated individuals of South Asian origin. Conclusions: In this report, we describe C8orf37 mutations that cause retinal dystrophy in two families of Pakistani origin, contributing further data on the phenotype and the spectrum of mutations in this form of retinitis pigmentosa
Haldane's Fractional Statistics and the Lowest Landau Level on a Torus
The Lowest Landau Level on a torus is studied. The dimension of the many-body
Hilbert space is obtained and is found to be different from the formula given
by Haldane. Our result can be tested in numerical investigations of the
low-energy spectrum of fractional quantum Hall states on a torus.Comment: 4 pages, Revtex. Small modifications. The modified version to appear
in Phys. Rev. Lett., Feb., 199
Pemberdayaan Masyarakat Melalui Kegiatan Pembibitan dan Penanaman Mangrove di Pantai Salurang, Kepulauan Sangihe
Mangrove memainkan peran sangat krusial bukan saja sebagai pelindung pesisir pantai tetapi juga sebagai tempat perkembangbiakan dan hunian beragam organisme dan sebagai sumber berbagai bahan bioaktif berpotensi medis. Kerusakan vegetasi mangrove di Kampung Salurang Kabupaten Sangihe yang merupakan daerah hilir akibat aktivitas tambang di daerah hulu menyebabkan penurunan drastis hasil tangkapan ikan di kampung Salurang dan musnahnya berbagai sumber bahan bioaktif potential. Kegiatan pengabdian masyarakat ini bertujuan memulihkan vegetasi mangrove yang telah rusak di kampung Salurang. Tahapan kegiatan pengabdian meliputi (1) survei dan konsultasi dengan pemerintah kampung untuk menentukan lokasi penanaman dan tanggal pemberian materi penyuluhan, (2) pendampingan untuk pembibitan mangrove oleh tim kepada masyarakat, (3) pelaksanaan kegiatan mencakup pemberian materi kepada masyarakat termasuk pemuda dan siswa sekolah menengah pertama dan penanaman mangrove bersama masyarakat. Hingga saat ini, sekitar 76% dari 95% mangrove yang ditanam tumbuh dengan baik dan pertumbuhannya masih terus dipantau. Kegiatan ini memiliki implikasi penting bukan saja untuk lingkungan dan kehidupan masyarakat pesisir tetapi juga untuk melindungi organisme simbion mangrove maupun mangrove itu sendiri sebagai sumber berbagai bahan bioaktif potensial
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