Artículos de revistas: "X e XI"

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Sierra, Isabel, Son Nguyen, Eric Joyce y Montserrat C. Anguera. "Investigating nuclear organization of the inactive X in female lymphocytes". Journal of Immunology 204, n.º 1_Supplement (1 de mayo de 2020): 151.12. http://dx.doi.org/10.4049/jimmunol.204.supp.151.12.

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Abstract Autoimmune diseases are devastating, incurable disorders that affect over 20 million people in the US, and many of these disorders have a striking female bias. The genetic basis for this sex-bias arises from the X chromosome. Female mammals, with two X chromosomes, utilize the epigenetic process of X Chromosome Inactivation (XCI), which transcriptionally silences one X. Expression of the long noncoding RNA Xist from the inactive X (Xi) reorganizes the Xi into a compact, bipartite structure, and targets the Xi to the nuclear periphery in somatic cells. The paradigm of XCI maintenance in somatic cells is stable association of Xist RNA and heterochromatic marks on the Xi, which function to maintain the Xi structure. Recently, we found a dynamic mechanism of XCI maintenance in female lymphocytes. In naïve female B cells, Xist RNA is not localized to the Xi, but after stimulation Xist RNA and heterochromatin marks return to the Xi. How this dynamic XCI process impacts Xi structure in lymphocytes is unknown, including which factors regulate Xi nuclear organization in this system. Using a novel allele-specific imaging system, we will present new findings on the compaction and organization of the Xi in lymphocytes. Additionally, we are investigating the regulatory roles of chromatin organization and nuclear structure proteins for lymphocyte-specific XCI maintenance, and how these factors regulate X-linked gene expression. Together, these results underscore the importance of Xi structure for the fidelity of XCI in female lymphocytes.

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2

Galego, Elói Medina. "BANACH SPACES OF CONTINUOUS VECTOR-VALUED FUNCTIONS OF ORDINALS". Proceedings of the Edinburgh Mathematical Society 44, n.º 1 (febrero de 2001): 49–62. http://dx.doi.org/10.1017/s0013091598000716.

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AbstractLet $X$ be a Banach space and $\xi$ an ordinal number. We study some isomorphic classifications of the Banach spaces $X^\xi$ of the continuous $X$-valued functions defined in the interval of ordinals $[1,\xi]$ and equipped with the supremum norm. More precisely, first we use the continuum hypothesis to give an isomorphic classification of $C(I)^\xi$, $\xi\geq\omega_1$. Then we present a characterization of the separable Banach spaces $X$ that are isomorphic to $X^\xi$, $\forall\xi$, $\omega\leq\xi lt \omega_1$. Finally, we show that the isomorphic classifications of $(C(I)\oplus F^*)^\xi$ and $\ell_\infty(\N)^\xi$, where $F$ is the space of Figiel and $\omega\leq\xi lt \omega_1$ are similar to that of $\R^\xi$ given by Bessaga and Pelczynski.AMS 2000 Mathematics subject classification: Primary 46B03; 46B20; 46E15

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3

Robbio, Matías Sebastían Fernandez. "Los períodos hipotéticos como recurso argumentativo en epigramas atribuidos a Luciano de Samosata". Nuntius Antiquus 9, n.º 2 (31 de diciembre de 2013): 41–56. http://dx.doi.org/10.17851/1983-3636.9.2.41-56.

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Espalhados em seis livros da Antologia Grega acham-se sessenta e quatro epigramas atribuídos a Luciano de Samósata. Analisa- se aqui uma seleção de catorze deles, que apresentam períodos hipotéticos: X.30, X.31, X.35, X.41, X.45, XI.129, XI.274, XI.396, XI.404, XI.420, XI.430, XI.431, XI.434, XVI.163. Focar-nos-emos no estudo dessa estrutura sintática a partir de três perspectivas: a morfologia e a sintaxe da língua grega, a prosódia e o uso retórico dos períodos hipotéticos, ao qual o autor recorre como estratégia argumentativa.

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4

Bu, Weichun, Tianqing An, Guoju Ye y Yating Guo. "Nonlocal fractional $ p(\cdot) $-Kirchhoff systems with variable-order: Two and three solutions". AIMS Mathematics 6, n.º 12 (2021): 13797–823. http://dx.doi.org/10.3934/math.2021801.

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<abstract>In this article, we consider the following nonlocal fractional Kirchhoff-type elliptic systems <disp-formula> <label/> <tex-math id="FE1"> \begin{document}$ \begin{equation*} \left\{\begin{array}{l} -M_{1}\left(\int_{\mathbb{R}^{N}\times\mathbb{R}^{N}}\frac{|\eta(x)-\eta(y)|^{^{p(x, y)}}}{p(x, y)|x-y|^{N+p(x, y)s(x, y)}} \ \ \ \ \ dxdy +\int_{\Omega}\frac{|\eta|^{\overline{p}(x)}}{\overline{p}(x)}dx\right) \left(\Delta_{p(\cdot)}^{s(\cdot)}\eta-|\eta|^{\overline{p}(x)}\eta\right)\\ \; \; \; = \lambda F_{\eta}(x, \eta, \xi)+\mu G_{\eta}(x, \eta, \xi), \; \; x \in \Omega, \\ -M_{2}\left(\int_{\mathbb{R}^{N}\times\mathbb{R}^{N}}\frac{|\xi(x)-\xi(y)|^{^{p(x, y)}}}{p(x, y)|x-y|^{N+p(x, y)s(x, y)}} \ \ \ \ \ dxdy +\int_{\Omega}\frac{|\xi|^{\overline{p}(x)}}{\overline{p}(x)}dx\right) \left(\Delta_{p(\cdot)}^{s(\cdot)}\xi-|\xi|^{\overline{p}(x)}\xi\right)\\ \; \; \; = \lambda F_{\xi}(x, \eta, \xi)+\mu G_{\xi}(x, \eta, \xi), \; \; x \in \Omega, \\ \; \eta = \xi = 0, \; \; x \in \mathbb{R}^{N}\backslash \Omega, \end{array} \right. \end{equation*} $\end{document} </tex-math></disp-formula> where $ M_{1}(t), M_{2}(t) $ are the models of Kirchhoff coefficient, $ \Omega $ is a bounded smooth domain in $ \mathbb R^{N} $, $ (-\Delta)_{p(\cdot)}^{s(\cdot)} $ is a fractional Laplace operator, $ \lambda, \mu $ are two real parameters, $ F, G $ are continuous differentiable functions, whose partial derivatives are $ F_{\eta}, F_{\xi}, G_{\eta}, G_{\xi} $. With the help of direct variational methods, we study the existence of solutions for nonlocal fractional $ p(\cdot) $-Kirchhoff systems with variable-order, and obtain at least two and three weak solutions based on Bonanno's and Ricceri's critical points theorem. The outstanding feature is the case that the Palais-Smale condition is not requested. The major difficulties and innovations are nonlocal Kirchhoff functions with the presence of the Laplace operator involving two variable parameters.</abstract>

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5

Putra, Reza Anantyo Adhi y Endang Sri Indrawati. "HUBUNGAN ANTARA KECERDASAN EMOSIONAL DENGAN INTENSI AGRESI PADA SISWA KELAS XI SMK X SEMARANG". Jurnal EMPATI 6, n.º 1 (16 de enero de 2017): 357–64. http://dx.doi.org/10.14710/empati.2017.15152.

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Penelitian ini bertujuan untuk mengetahui hubungan antara kecerdasan emosional dengan intensi agresi pada siswa kelas XI SMK X Semarang.Populasi penelitian sebanyak 146 siswa kelas XI SMK X Semarang.Uji coba diberikankepada 67 siswa kelas XI SMK X Semarang dan penelitian dilakukan kepada 79 siswa kelas XI SMK X Semarang.Teknik sampling yang digunakan adalah cluster random sampling.Alat ukur yang digunakan pada penelitian ini adalah skala intensi agresi (46 aitem, α = 0,923) dan skala kecerdasan emosional (30 aitem, α =0,901).Metode analisis data yang digunakan pada penelitian ini dengan analisis regresi sederhana.Hasil penelitian menunjukkan bahwa ada hubungan negatifsignifikan antara kecerdasan emosional dengan intensi agresi pada siswakelas XI SMK X Semarang (r= -0,549; p< 0,001). Hal tersebut menunjukan bahwa hipotesis yang diajukan peneliti, yaitu hubungan negatif antara kecerdasan emosional dengan intensi agresi pada siswa kelas XI SMK X Semarang dapat diterima. Semakin tinggi kecerdasan emosional maka semakin rendah intensi agresi pada siswa kelas XI SMK X Semarang, sebaliknya semakin rendah kecerdasan emosional maka semakin tinggi intensi agresi siswa kelas XISMK X Semarang. Variabelkecerdasan emosional memberikan sumbangan efektif sebesar 30,1% terhadap intensi agresi.

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6

Guo, Qing y Huafei Xie. "Non-Degeneracy of Peak Solutions to the Schrödinger–Newton System". Advanced Nonlinear Studies 21, n.º 2 (15 de abril de 2021): 447–60. http://dx.doi.org/10.1515/ans-2021-2128.

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Abstract We are concerned with the following Schrödinger–Newton problem: - ε 2 ⁢ Δ ⁢ u + V ⁢ ( x ) ⁢ u = 1 8 ⁢ π ⁢ ε 2 ⁢ ( ∫ ℝ 3 u 2 ⁢ ( ξ ) | x - ξ | ⁢ 𝑑 ξ ) ⁢ u , x ∈ ℝ 3 . -\varepsilon^{2}\Delta u+V(x)u=\frac{1}{8\pi\varepsilon^{2}}\Bigg{(}\int_{% \mathbb{R}^{3}}\frac{u^{2}(\xi)}{|x-\xi|}\,d\xi\Bigg{)}u,\quad x\in\mathbb{R}^% {3}. For ε small enough, we prove the non-degeneracy of the positive solution to the above problem, that is, the corresponding linear operator ℒ ε ⁢ ( η ) = - ε 2 ⁢ Δ ⁢ η ⁢ ( x ) + V ⁢ ( x ) ⁢ η ⁢ ( x ) - 1 8 ⁢ π ⁢ ε 2 ⁢ ( ∫ ℝ 3 u ε 2 ⁢ ( ξ ) | x - ξ | ⁢ 𝑑 ξ ) ⁢ η ⁢ ( x ) - 1 4 ⁢ π ⁢ ε 2 ⁢ ( ∫ ℝ 3 u ε ⁢ ( ξ ) ⁢ η ⁢ ( ξ ) | x - ξ | ⁢ 𝑑 ξ ) ⁢ u ε ⁢ ( x ) \mathcal{L}_{\varepsilon}(\eta)=-\varepsilon^{2}\Delta\eta(x)+V(x)\eta(x)-% \frac{1}{8\pi\varepsilon^{2}}\Bigg{(}\int_{\mathbb{R}^{3}}\frac{u_{\varepsilon% }^{2}(\xi)}{|x-\xi|}\,d\xi\Bigg{)}\eta(x)-\frac{1}{4\pi\varepsilon^{2}}\Bigg{(% }\int_{\mathbb{R}^{3}}\frac{u_{\varepsilon}(\xi)\eta(\xi)}{|x-\xi|}\,d\xi\Bigg% {)}u_{\varepsilon}(x) is non-degenerate, i.e., ℒ ε ⁢ ( η ε ) = 0 ⇒ η ε = 0 {\mathcal{L}_{\varepsilon}(\eta_{\varepsilon})=0\Rightarrow\eta_{\varepsilon}=0} for small ε > 0 {\varepsilon>0} . The main tools are the local Pohozaev identities and the blow-up analysis. This may be the first non-degeneracy result on the peak solutions to the Schrödinger–Newton system.

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7

Plath, Kathrin, Dale Talbot, Karien M. Hamer, Arie P. Otte, Thomas P. Yang, Rudolf Jaenisch y Barbara Panning. "Developmentally regulated alterations in Polycomb repressive complex 1 proteins on the inactive X chromosome". Journal of Cell Biology 167, n.º 6 (13 de diciembre de 2004): 1025–35. http://dx.doi.org/10.1083/jcb.200409026.

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Polycomb group (PcG) proteins belonging to the polycomb (Pc) repressive complexes 1 and 2 (PRC1 and PRC2) maintain homeotic gene silencing. In Drosophila, PRC2 methylates histone H3 on lysine 27, and this epigenetic mark facilitates recruitment of PRC1. Mouse PRC2 (mPRC2) has been implicated in X inactivation, as mPRC2 proteins transiently accumulate on the inactive X chromosome (Xi) at the onset of X inactivation to methylate histone H3 lysine 27 (H3-K27). In this study, we demonstrate that mPRC1 proteins localize to the Xi, and that different mPRC1 proteins accumulate on the Xi during initiation and maintenance of X inactivation in embryonic cells. The Xi accumulation of mPRC1 proteins requires Xist RNA and is not solely regulated by the presence of H3-K27 methylation, as not all cells that exhibit this epigenetic mark on the Xi show Xi enrichment of mPRC1 proteins. Our results implicate mPRC1 in X inactivation and suggest that the regulated assembly of PcG protein complexes on the Xi contributes to this multistep process.

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8

Shestakova, E. A. y T. A. Bogush. "BRCa1 participates in XIST RNa localization on inactive x chromosome". Russian Journal of Biotherapy 18, n.º 2 (15 de junio de 2019): 21–26. http://dx.doi.org/10.17650/1726-9784-2019-18-2-21-26.

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Introduction . Inactive X chromosome (Xi) is associated with noncoding XIST RNA, series of proteins and contains multiple epigenetic modifications that altogether determine a silence of the most of X-linked genes. Recently the data were obtained that tumor suppressor BRCA1 is also associated with Xi. The purpose of this study was to reveal the colocalization of BRCA1 and XIST RNA and precise spatial organization on Xi with the high resolution of confocal microscopy.Materials and methods . The object of the study is IMR90hTERT diploid immortalized fibroblast cell line. For BRCA1 and XIST RNA colocalization analysis on Xi the method of fluorescent hybridization in situ associated with immunofluorescent cell staining (immunoFISH) and confocal microscopy were used. For BRCA1 and heterochromatin protein-1 colocalization study the method of double immunofluorescent staining and common fluorescent microscopy were applied. Results . The study using confocal fluorescent microscopy with higher resolution has demonstrated at first the colocalization of BRCA1 with XIST RNA region of Xi revealed with XIST RNA probes and with replicating Xi and autosomes revealed with BrdU in late S-phase of cell cycle. Altogether, the data obtained suggest the involvement of BRCA1 in the inhibition of gene expression on Xi due to the regulation of XIST RNA association with Xi. Moreover, according to the results of confocal microscopy, BRCA1 also colocalizes with replicating Xi and autosomes revealed with BrdU in late S-phase of cell cycle. This indicates a possible involvement of this protein in the replication of pericentromeric repeats in cellular chromosomes. Colocalization of BRCA1 with heterochromatin protein-1α presented in pericentromeric regions of all chromosomes supports this suggestion.Conclusions . Altogether, the data obtained in this study suggest the involvement of BRCA1 in the inhibition of gene expression on Xi due to the association with noncoding inhibiting XIST RNA and in replication of heterochromatin regions.

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9

Mermoud, Jacqueline E., Carl Costanzi, John R. Pehrson y Neil Brockdorff. "Histone Macroh2a1.2 Relocates to the Inactive X Chromosome after Initiation and Propagation of X-Inactivation". Journal of Cell Biology 147, n.º 7 (27 de diciembre de 1999): 1399–408. http://dx.doi.org/10.1083/jcb.147.7.1399.

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The histone macroH2A1.2 has been implicated in X chromosome inactivation on the basis of its accumulation on the inactive X chromosome (Xi) of adult female mammals. We have established the timing of macroH2A1.2 association with the Xi relative to the onset of X-inactivation in differentiating murine embryonic stem (ES) cells using immuno-RNA fluorescence in situ hybridization (FISH). Before X-inactivation we observe a single macroH2A1.2-dense region in both undifferentiated XX and XY ES cells that does not colocalize with X inactive specific transcript (Xist) RNA, and thus appears not to associate with the X chromosome(s). This pattern persists through early stages of differentiation, up to day 7. Then the frequency of XY cells containing a macroH2A1.2-rich domain declines. In contrast, in XX cells there is a striking relocalization of macroH2A1.2 to the Xi. Relocalization occurs in a highly synchronized wave over a 2-d period, indicating a precisely regulated association. The timing of macroH2A1.2 accumulation on the Xi suggests it is not necessary for the initiation or propagation of random X-inactivation.

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10

Ganesan, Shridar, Daniel P. Silver, Ronny Drapkin, Roger Greenberg, Jean Feunteun y David M. Livingston. "Association of BRCA1 with the inactive X chromosome and XIST RNA". Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 359, n.º 1441 (29 de enero de 2004): 123–28. http://dx.doi.org/10.1098/rstb.2003.1371.

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Breast cancer, early onset 1 (BRCA1) encodes a nuclear protein that participates in breast and ovarian cancer suppression. The molecular basis for the gender and tissue specificity of the BRCA1 cancer syndrome is unknown. Recently, we observed that a fraction of BRCA1 in female cells is localized on the inactive X chromosome (Xi). Chromatin immunoprecipitation (ChIP) experiments have demonstrated that BRCA1 physically associates with Xi–specific transcript (XIST) RNA, a non–coding RNA known to coat Xi and to participate in the initiation of its inactivation during early embryogenesis. Cells lacking wild–type BRCA1 show abnormalities in Xi, including lack of proper XIST RNA localization. Reintroduction of wild–type, but not mutant, BRCA1 can correct this defect in XIST localization in these cells. Depletion of BRCA1 in female diploid cells led to a defect in proper XIST localization on Xi and in the development of normal Xi heterchromatic superstructure. Moreover, depletion of BRCA1 led to an increased likelihood of re–expression of a green fluorescent protein (GFP) reporter gene embedded on Xi. Taken together, these findings are consistent with a model in which BRCA1 function contributes to the maintenance of proper Xi heterochromatin superstructure. Although the data imply a novel gender–specific consequence of BRCA1 loss, the relevance of the BRCA1/Xi function to the tumour suppressor activity of BRCA1 remains unclear and needs to be tested.

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11

Surasmi, I. Gusti Ayu. "Hubungan Jawa-Bali Abad X-XI". Berkala Arkeologi 14, n.º 2 (30 de mayo de 1994): 119–22. http://dx.doi.org/10.30883/jba.v14i2.710.

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Artikel ini memaparkan hubungan Jawa dan Bali abad X-XI. Abad itu menjadi latar waktu peristiwa yang menarik yaitu terjadinya perkawinan antara raja Udayana dan keluarga raja Warmadewa di Bali dengan Çri Gunapriyadharmapatni keturunan raja Sindok dari Jawa Timur. Perkawinan ini ternyata menarik untuk dikaji. Uraian berikut akan mencoba mengkaji seberapa jauh peranan Çri Gunapriyadharmapatni dalam hubungan Jawa Bali. Sumber utama yang digunakan sebagai bahan kajian dalam penulisan ini adalah beberapa prasasti dan peninggalan arkeologi khususnya area-area yang mempunyai kaitan dengan Çri Gunapriyadharmapatni.

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12

Hanoune, Roger y Arthur Muller. "Recherches archéologiques à Bavay, X-XI". Revue du Nord 73, n.º 292 (1991): 101–19. http://dx.doi.org/10.3406/rnord.1991.4685.

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13

Warr, Wendy A. "EndNote X (and XI) for Windows". Journal of Chemical Information and Modeling 48, n.º 1 (4 de diciembre de 2007): 242–44. http://dx.doi.org/10.1021/ci7003708.

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14

Hong, Qing, Guozhen Lu y Lu Zhang. "L p boundedness of rough bi-parameter Fourier integral operators". Forum Mathematicum 30, n.º 1 (1 de enero de 2018): 87–107. http://dx.doi.org/10.1515/forum-2016-0221.

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Abstract In this paper, we will investigate the boundedness of the bi-parameter Fourier integral operators (or FIOs for short) of the following form: T(f\/)(x)=\frac{1}{(2\pi)^{2n}}\int_{\mathbb{R}^{2n}}e^{i\varphi(x,\xi,\eta)}% \cdot a(x,\xi,\eta)\cdot\widehat{f}(\xi,\eta)\,d\xi\,d\eta, where {x=(x_{1},x_{2})\in\mathbb{R}^{n}\times\mathbb{R}^{n}} and {\xi,\eta\in\mathbb{R}^{n}\setminus\{0\}} , {a(x,\xi,\eta)\in L^{\infty}BS^{m}_{\rho}} is the amplitude, and the phase function is of the form \varphi(x,\xi,\eta)=\varphi_{1}(x_{1},\xi\/)+\varphi_{2}(x_{2},\eta) , with \varphi_{1},\varphi_{2}\in L^{\infty}\Phi^{2}(\mathbb{R}^{n}\times\mathbb{R}^{% n}\setminus\{0\}) , and satisfies a certain rough non-degeneracy condition (see (2.2)). The study of these operators are motivated by the {L^{p}} estimates for one-parameter FIOs and bi-parameter Fourier multipliers and pseudo-differential operators. We will first define the bi-parameter FIOs and then study the {L^{p}} boundedness of such operators when their phase functions have compact support in frequency variables with certain necessary non-degeneracy conditions. We will then establish the {L^{p}} boundedness of the more general FIOs with amplitude {a(x,\xi,\eta)\in L^{\infty}BS^{m}_{\rho}} and non-smooth phase function {\varphi(x,\xi,\eta)} on x satisfying a rough non-degeneracy condition.

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15

Wu, H., R. Fassler, A. Schnieke, D. Barker, K. H. Lee, V. Chapman, U. Francke y R. Jaenisch. "An X-linked human collagen transgene escapes X inactivation in a subset of cells". Development 116, n.º 3 (1 de noviembre de 1992): 687–95. http://dx.doi.org/10.1242/dev.116.3.687.

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Transgenic mice carrying one complete copy of the human alpha 1(I) collagen gene on the X chromosome (HucII mice) were used to study the effect of X inactivation on transgene expression. By chromosomal in situ hybridization, the transgene was mapped to the D/E region close to the Xce locus, which is the controlling element. Quantitative RNA analyses indicated that transgene expression in homozygous and heterozygous females was about 125% and 62%, respectively, of the level found in hemizygous males. Also, females with Searle's translocation carrying the transgene on the inactive X chromosome (Xi) expressed about 18% transgene RNA when compared to hemizygous males. These results were consistent with the transgene being subject to but partially escaping from X inactivation. Two lines of evidence indicated that the transgene escaped X inactivation or was reactivated in a small subset of cells rather than being expressed at a lower level from the Xi in all cells, (i) None of nine single cell clones carrying the transgene on the Xi transcribed transgene RNA. In these clones the transgene was highly methylated in contrast to clones carrying the transgene on the Xa. (ii) In situ hybridization to RNA of cultured cells revealed that about 3% of uncloned cells with the transgene on the Xi expressed transgene RNA at a level comparable to that on the Xa. Our results indicate that the autosomal human collagen gene integrated on the mouse X chromosome is susceptible to X inactivation. Inactivation is, however, not complete as a subset of cells carrying the transgene on Xi expresses the transgene at a level comparable to that when carried on Xa.

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Кыров, В. А. "Nondegenerate Canonical Solutions of a Certain System of Functional Equations". Владикавказский математический журнал, n.º 1 (29 de marzo de 2022): 44–53. http://dx.doi.org/10.46698/u7680-5193-0172-d.

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Установление возможности вложения неаддитивной двуметрической феноменологически симметричной геометрии ранга $(2,2)$ с функцией $g(x, y, \xi, \eta) =(g^{1}, g^{2}) $ в двуметрическую феноменологически симметричную геометрию ранга $(3,2)$ с~функцией $f(x, y, \xi, \eta, \mu, \nu) =(f^{1}, f^{2}) $ приводит к задаче нахождения у соответствующей системы $ f(\bar{x}, \bar{y}, \bar{\xi}, \bar{\eta}, \bar{\mu}, \bar{\nu}) = \chi(g(x, y, \xi, \eta), \mu, \nu) $ двух функциональных уравнений невырожденных решений. Данная система решается, поскольку функции $g$ и $f$ ранее известны. Тогда эта система принимает явный вид: $\bar{x}\bar{\xi}+\bar{y}\bar{\mu}=\chi ^{1}((x+\xi)y,(x+\xi)\eta,\mu,\nu ),$ $\bar{x}\bar{\eta}+\bar{y}\bar{\nu}=\chi ^{2}((x+\xi )y,(x+\xi )\eta ,\mu ,\nu).$ Общее решение такой системы найти трудно, однако можно сначала найти каноническое решение, связанное с жордановой формой матриц второго порядка, поскольку их количество мало, а затем по нему определить общее решение с помощью подходящего невырожденного преобразования матриц и векторов. Такая переформулировка основной проблемы делает ее более простой и интересной в математическом смысле.В процессе поиска канонических решений исходной системы функциональных уравнений сначала дифференцируем по переменным $x$ и $\xi$, в результате получаем систему дифференциальных уравнений с матрицей коэффициентов $A$ общего вида: $\left(\!\begin{array}{c} {\bar{x}_{x}} \\ {\bar{y}_{x}} \end{array}\!\right)=A\left(\!\begin{array}{c} {\bar{x}} \\ {\bar{y}} \end{array}\!\right)$. Доказывается, что матрицу $A$ можно привести к жорданову виду. Затем решается система дифференциальных уравнений с такой жордановой матрицей. Далее, с решениями системы дифференциальных уравнений возвращается в исходную систему функциональных уравнений, откуда находятся дополнительные ограничения. В~итоге получаются невырожденные канонические решения исходной системы функциональных уравнений. По этим каноническим решениям затем записывается общие решения исходной системы.

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17

Panova, A. V., E. D. Nekrasov, M. A. Lagarkova, S. L. Kiselev y A. N. Bogomazova. "Late Replication of the Inactive X Chromosome Is Independent of the Compactness of Chromosome Territory in Human Pluripotent Stem Cells". Acta Naturae 5, n.º 2 (15 de junio de 2013): 54–61. http://dx.doi.org/10.32607/20758251-2013-5-2-54-61.

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Dosage compensation of the X chromosomes in mammals is performed via the formation of facultative heterochromatin on extra X chromosomes in female somatic cells. Facultative heterochromatin of the inactivated X (Xi), as well as constitutive heterochromatin, replicates late during the S-phase. It is generally accepted that Xi is always more compact in the interphase nucleus. The dense chromosomal folding has been proposed to define the late replication of Xi. In contrast to mouse pluripotent stem cells (PSCs), the status of X chromosome inactivation in human PSCs may vary significantly. Fluorescence in situ hybridization with a whole X-chromosome-specific DNA probe revealed that late-replicating Xi may occupy either compact or dispersed territory in human PSCs. Thus, the late replication of the Xi does not depend on the compactness of chromosome territory in human PSCs. However, the Xi reactivation and the synchronization in the replication timing of X chromosomes upon reprogramming are necessarily accompanied by the expansion of X chromosome territory.

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18

Luo, Zhenguo. "Multiple Positive Periodic Solutions for Two Kinds of Higher-Dimension Impulsive Differential Equations with Multiple Delays and Two Parameters". Journal of Mathematics 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/214093.

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By applying the fixed point theorem, we derive some new criteria for the existence of multiple positive periodic solutions for two kinds of n-dimension periodic impulsive functional differential equations with multiple delays and two parameters:xi′(t)=ai(t)xi(t)-λbi(t)fi(t,x(t),x(t-τ1(t)),…,x(t-τn(t)))), a.e.,t>0,t≠tk,k∈Z+,xi(tk+)-xi(tk-)=μcikxi(tk),i=1,2,…,n,k∈Z+,andxi′(t)=-ai(t)xi(t)+λbi(t)fi(t,x(t),x(t-τ1(t)),…,x(t-τn(t)))), a.e.,t>0,t≠tk,k∈Z+,xi(tk+)-xi(tk-)=μcikxi(tk),i=1,2,…,n,k∈Z+.As an application, we study some special cases of the previous systems, which have been studied extensively in the literature.

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19

Cano Ávila, Pedro. "El jurista sevillano lbn al-Makwi (s. X-XI)". Philologia Hispalensis 1, n.º 7 (1992): 123–40. http://dx.doi.org/10.12795/ph.1992.v07.i01.11.

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Prabayanti, Ni Made Dian, I. Ketut Sudiana y Ni Made Wiratini. "ANALISIS TES ULANGAN KENAIKAN KELAS BUATAN GURU MATA PELAJARAN KIMIA". Jurnal Pendidikan Kimia Indonesia 2, n.º 1 (1 de mayo de 2018): 25. http://dx.doi.org/10.23887/jpk.v2i1.14127.

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Penelitian ini bertujuan untuk mendeskripsikan dan menjelaskan kualitas tes ulangan kenaikan kelas X dan XI IPA mata pelajaran kimia di SMA Laboratorium Undiksha. Penelitian ini menggunakan jenis penelitian evaluatif dengan metode analisis data yaitu deskriptif interpretatif. Subjek penelitian dalam penelitian ini adalah naskah soal ulangan kenaikan kelas X dan XI IPA tahun ajaran 2016/2017 mata pelajaran kimia. Hasil penelitian menunjukkan bahwa: (1) validitas isi tes ulangan kenaikan kelas X tergolong tinggi dan validitas isi tes ulangan kenaikan kelas XI IPA tergolong sedang, (2) validitas konstruk tes ulangan kenaikan kelas X dan XI IPA tergolong tinggi, (3) bahasa tes ulangan kenaikan kelas X dan XI IPA tinggi, (4) validitas butir soal tes ulangan kenaikan kelas X dan XI IPA termasuk berkualitas baik, (5) reliabilitas tes pilihan ganda ulangan kenaikan kelas X tergolong dalam kategori tinggi, sedangkan reliabilitas tes uraian tergolong rendah, reliabilitas tes ulangan kenaikan kelas XI IPA tergolong sangat tinggi, (6) daya pembeda tes ulangan kenaikan kelas X pembeda berkualitas baik, sedangkan tes ulangan kenaikan kelas XI IPA bentuk pilihan ganda tergolong cukup baik dan bentuk uraian tergolong baik, (7) tingkat kesukaran tes ulangan kenaikan kelas X dan XI IPA tergolong baik, (8) efektifitas pengecoh yang berfungsi dengan baik pada tes ulangan kenaikan kelas X sebanyak 81 pengecoh, sedangkan kelas XI IPA sebanyak 69 pengecoh, dan (9) masih terdapat soal dengan ranah kognitif taksonomi bloom yang berbeda dengan ranah kognitif taksonomi bloom pada indikator. Saran yang dapat peneliti sampaikan terhadap hasil penelitian ini yaitu bagi sekolah agar memfasilitasi guru untuk dapat meningkatkan kompetensi pedagogik melalui forum akademik seperti pelatihan, seminar, atau sejenisnya terkait penilaian (assesment).

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21

Wang, Jianle, Camille M. Syrett, Marianne C. Kramer, Arindam Basu, Michael L. Atchison y Montserrat C. Anguera. "Unusual maintenance of X chromosome inactivation predisposes female lymphocytes for increased expression from the inactive X". Proceedings of the National Academy of Sciences 113, n.º 14 (21 de marzo de 2016): E2029—E2038. http://dx.doi.org/10.1073/pnas.1520113113.

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Females have a greater immunological advantage than men, yet they are more prone to autoimmune disorders. The basis for this sex bias lies in the X chromosome, which contains many immunity-related genes. Female mammals use X chromosome inactivation (XCI) to generate a transcriptionally silent inactive X chromosome (Xi) enriched with heterochromatic modifications and XIST/Xist RNA, which equalizes gene expression between the sexes. Here, we examine the maintenance of XCI in lymphocytes from females in mice and humans. Strikingly, we find that mature naïve T and B cells have dispersed patterns of XIST/Xist RNA, and they lack the typical heterochromatic modifications of the Xi. In vitro activation of lymphocytes triggers the return of XIST/Xist RNA transcripts and some chromatin marks (H3K27me3, ubiquitin-H2A) to the Xi. Single-cell RNA FISH analysis of female T cells revealed that the X-linked immunity genes CD40LG and CXCR3 are biallelically expressed in some cells. Using knockout and knockdown approaches, we find that Xist RNA-binding proteins, YY1 and hnRNPU, are critical for recruitment of XIST/Xist RNA back to the Xi. Furthermore, we examined B cells from patients with systemic lupus erythematosus, an autoimmune disorder with a strong female bias, and observed different XIST RNA localization patterns, evidence of biallelic expression of immunity-related genes, and increased transcription of these genes. We propose that the Xi in female lymphocytes is predisposed to become partially reactivated and to overexpress immunity-related genes, providing the first mechanistic evidence to our knowledge for the enhanced immunity of females and their increased susceptibility for autoimmunity.

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22

D.J, Winda Putri y Endang Sri Indrawati. "HUBUNGAN ANTARA KECERDASAN EMOSIONAL DENGAN PERILAKU BULLYING PADA SISWA KELAS XI SMK X SEMARANG". Jurnal EMPATI 8, n.º 1 (26 de marzo de 2019): 253–59. http://dx.doi.org/10.14710/empati.2019.23601.

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Penelitian ini bertujuan unutk mengetahui hubungan antara kecerdasan emosional dengan perilaku bullying pada siswa kelas XI SMK X Semarang. Populasi pada penelitian sebanyak 149 siswa kelas XI X Semarang. Uji coba diberikan kepada 43 siswa kelas XI SMK X Semarang dan penelitian dilakukan kepada 105 siswa kelas XI SMK X Semarang. Teknik sampling yang digunakan adalah cluster random sampling. Alat ukur yang digunakan pada penelitian ini adalah skala kecerdasan emosional (27 aitem, α =0,894) dan skala perilaku bullying ( 23 aitem, α =0,944). Metode analisis data yang digunakan pada penelitian ini dengan analisis regresi sederhana. Hasil penelitian menunjukan terdapat hubungan negatif signifikan antara kecerdasan emosional dengan perilaku bullying (rxy = -0,352 ; p= 0,000). Hal ini menunjukan bahwa hipotesis yang diajukan peneliti terkait hubungan negatif antara kecerdasan emosional dengan perilaku bullying pada siswa kelas XI SMK X Semarang dapat diterima. Kecerdasan emosional pada penelitian ini memberikan sumbangan efektif sebesar 12,4% terhadap perilaku bullying

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23

Наумкин, Павел Иванович y Pavel Ivanovich Naumkin. "Асимптотика решений модифицированного уравнения Уизема, учитывающего поверхностное натяжение". Известия Российской академии наук. Серия математическая 83, n.º 2 (2019): 174–203. http://dx.doi.org/10.4213/im8673.

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Изучено поведение при больших временах решений задачи Коши для модифицированного уравнения Уизема $$ \begin{cases} u_{t}+i\mathbf{\Lambda}u-\partial_{x}u^3=0, &(t,x) \in\mathbb{R}^2, u(0,x)=u_0(x), &x\in \mathbb{R}, \end{cases} $$ где псевдодифференциальный оператор $\mathbf{\Lambda}\equiv \Lambda (-i\partial_{x})=\mathcal{F}^{-1}[\Lambda (\xi) \mathcal{F}]$ задается с помощью символа $$ \Lambda (\xi)=a^{-{1}/{2}}\xi (\sqrt{(1+a^2\xi^2) \frac{\operatorname{th} a\xi}{a\xi}}-1); $$ здесь параметр $a>0$. Этот символ соответствует полному дисперсионному соотношению волн на воде с учетом поверхностного натяжения. В предположении, что полная масса начальных данных $\int_{\mathbb{R}}u_0(x) dx=0$ и начальные данные $u_0$ малы в норме $\mathbf{H}^{\nu}(\mathbb{R}) \cap \mathbf{H}^{0,1}(\mathbb{R})$, $\nu \geq 22$, доказано существование глобального по времени решения и описана его асимптотика при больших временах. Библиография: 17 наименований.

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24

Sapitri, Amelia, Tuti Kurniati y Asri Yuliawati. "Analisis Kualitas Soal UAS Biologi SMA Kelas X dan XI MIA". Bioeduca : Journal of Biology Education 4, n.º 1 (31 de marzo de 2022): 45–56. http://dx.doi.org/10.21580/bioeduca.v4i1.8433.

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Analisis soal memiliki peranan penting dalam mendapatkan kualitas butir soal yang baik untuk dijadikan sebagai alat evaluasi. Namun, fenomena yang terjadi banyak guru yang belum menganalisis kualitas soal. Tujuan penelitian ini untuk mengetahui kualitas soal UAS Biologi kelas X dan XI MIA SMA Negeri 1 Terusan Nunyai berdasarkan analisis teoritis dan empiris. Metode yang digunakan deskriptif dengan pendekatan kualitatif. Hasilnya kualitas soal kelas X berdasarkan analisis teoritis 32% baik, 20% sangat baik, 12% sedang, 28% kurang baik, dan 8% tidak baik. Sedangkan kelas XI 52% sangat baik, 36% baik, 4% kurang baik, dan 8% tidak baik. Kualitas butir soal kelas X berdasarkan analisis empiris 48% sedang, 20% kurang baik, 16% tidak baik, dan 16% baik. Pada kelas XI 32% baik, 24% kurang baik, 20% sedang,12% sangat baik, dan 12% tidak baik. Level kognitif yang digunakan kelas X C1 dan C2, serta kelas XI C1,C2,C3,dan C4. Mayoritas kualitas soal kelas X secara teoritis merupakan soal yang baik dan secara empiris sedang, serta mayoritas kualitas soal kelas XI secara teoritis sangat baik dan secara empiris baik.

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25

Коньков, Андрей Александрович y Andrej Alexandrovich Kon'kov. "Геометрические оценки решений квазилинейных эллиптических неравенств". Известия Российской академии наук. Серия математическая 84, n.º 6 (2020): 23–72. http://dx.doi.org/10.4213/im8974.

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Предположим, что $p>1$ и $p-1 \le \alpha \le p$ - некоторые вещественные числа, а $\Omega$ - непустое открытое подмножество $\mathbb{R}^n$, $n \ge 2$. Рассмотрим неравенство $$ \operatorname{div} A (x, D u)+b (x) |D u|^\alpha\ge 0, $$ где $D=(\partial/\partial x_1, \partial/\partial x_2, …, \partial/\partial x_n)$ - оператор градиента, $A\colon \Omega \times \mathbb{R}^n \to \mathbb{R}^n$ и $b\colon \Omega \to [0, \infty)$ - некоторые функции, причем $$ C_1|\xi|^p\le\xi A (x, \xi),\quad |A (x, \xi)|\le C_2|\xi|^{p-1},\qquad C_1, C_2=\mathrm{const}>0, \quad p>1, $$ для почти всех $x \in \Omega$ и всех $\xi \in \mathbb{R}^n$. Для решений этого неравенства получены оценки, учитывающие геометрию $\Omega$. Из этих оценок, в частности, следуют условия регулярности граничной точки. Библиография: 17 наименований.

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26

Silvestrov, D. "Convergence in distribution for randomly stopped random fields". Theory of Probability and Mathematical Statistics 105 (7 de diciembre de 2021): 137–49. http://dx.doi.org/10.1090/tpms/1160.

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Let X \mathbb {X} and Y \mathbb {Y} be two complete, separable, metric spaces, ξ ε ( x ) , x ∈ X \xi _\varepsilon (x), x \in \mathbb {X} and ν ε \nu _\varepsilon be, for every ε ∈ [ 0 , 1 ] \varepsilon \in [0, 1] , respectively, a random field taking values in space Y \mathbb {Y} and a random variable taking values in space X \mathbb {X} . We present general conditions for convergence in distribution for random variables ξ ε ( ν ε ) \xi _\varepsilon (\nu _\varepsilon ) that is the conditions insuring holding of relation, ξ ε ( ν ε ) ⟶ d ξ 0 ( ν 0 ) \xi _\varepsilon (\nu _\varepsilon ) \stackrel {\mathsf {d}}{\longrightarrow } \xi _0(\nu _0) as ε → 0 \varepsilon \to 0 .

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27

Darrow, Emily M., Miriam H. Huntley, Olga Dudchenko, Elena K. Stamenova, Neva C. Durand, Zhuo Sun, Su-Chen Huang et al. "Deletion of DXZ4 on the human inactive X chromosome alters higher-order genome architecture". Proceedings of the National Academy of Sciences 113, n.º 31 (18 de julio de 2016): E4504—E4512. http://dx.doi.org/10.1073/pnas.1609643113.

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During interphase, the inactive X chromosome (Xi) is largely transcriptionally silent and adopts an unusual 3D configuration known as the “Barr body.” Despite the importance of X chromosome inactivation, little is known about this 3D conformation. We recently showed that in humans the Xi chromosome exhibits three structural features, two of which are not shared by other chromosomes. First, like the chromosomes of many species, Xi forms compartments. Second, Xi is partitioned into two huge intervals, called “superdomains,” such that pairs of loci in the same superdomain tend to colocalize. The boundary between the superdomains lies near DXZ4, a macrosatellite repeat whose Xi allele extensively binds the protein CCCTC-binding factor. Third, Xi exhibits extremely large loops, up to 77 megabases long, called “superloops.” DXZ4 lies at the anchor of several superloops. Here, we combine 3D mapping, microscopy, and genome editing to study the structure of Xi, focusing on the role of DXZ4. We show that superloops and superdomains are conserved across eutherian mammals. By analyzing ligation events involving three or more loci, we demonstrate that DXZ4 and other superloop anchors tend to colocate simultaneously. Finally, we show that deleting DXZ4 on Xi leads to the disappearance of superdomains and superloops, changes in compartmentalization patterns, and changes in the distribution of chromatin marks. Thus, DXZ4 is essential for proper Xi packaging.

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28

Lin, Tsung-Wu y Hejie Lin. "Mechanical Proof of the Maxwell Speed Distribution". International Journal of Statistics and Probability 8, n.º 2 (25 de enero de 2019): 90. http://dx.doi.org/10.5539/ijsp.v8n2p90.

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This article derives the probability density function ψξ;x,x'  of the resulting speed ξ  from the collision of two particles with speeds x  and x' . This function had been left unsolved for about 150 years. Then uses two approaches to obtain the Maxwell speed distribution: (1) Numerical iteration: using the equation Pnewξ=0∞0∞ψξ;x,x' ∙Poldx∙Poldx' dxdx'   to get the new speed distribution from the old speed distribution. Also, after 9 iterations, the distribution converges to the Maxwell speed distribution. (2) Analytical integration: using the Maxwell speed distribution as the Poldx , and then getting Pnewξ  from the above integration. The result of Pnewξ  from analytical integration is proved to be exactly the Maxwell speed distribution.

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29

Lessing, Derek, Thomas O. Dial, Chunyao Wei, Bernhard Payer, Lieselot L. G. Carrette, Barry Kesner, Attila Szanto et al. "A high-throughput small molecule screen identifies synergism between DNA methylation and Aurora kinase pathways for X reactivation". Proceedings of the National Academy of Sciences 113, n.º 50 (23 de noviembre de 2016): 14366–71. http://dx.doi.org/10.1073/pnas.1617597113.

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X-chromosome inactivation is a mechanism of dosage compensation in which one of the two X chromosomes in female mammals is transcriptionally silenced. Once established, silencing of the inactive X (Xi) is robust and difficult to reverse pharmacologically. However, the Xi is a reservoir of >1,000 functional genes that could be potentially tapped to treat X-linked disease. To identify compounds that could reactivate the Xi, here we screened ∼367,000 small molecules in an automated high-content screen using an Xi-linked GFP reporter in mouse fibroblasts. Given the robust nature of silencing, we sensitized the screen by “priming” cells with the DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine (5azadC). Compounds that elicited GFP activity include VX680, MLN8237, and 5azadC, which are known to target the Aurora kinase and DNA methylation pathways. We demonstrate that the combinations of VX680 and 5azadC, as well as MLN8237 and 5azadC, synergistically up-regulate genes on the Xi. Thus, our work identifies a synergism between the DNA methylation and Aurora kinase pathways as being one of interest for possible pharmacological reactivation of the Xi.

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30

Marsden, M. J. "A Voronovskaya Theorem for Variation-Diminishing Spline Approximation". Canadian Journal of Mathematics 38, n.º 5 (1 de octubre de 1986): 1081–93. http://dx.doi.org/10.4153/cjm-1986-053-0.

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In [7] Schoenberg introduced the following variation-diminishing spline approximation methods.Let m > 1 be an integer and let Δ = {xi} be a biinfinite sequence of real numbers with xi ≧ xi + l < xi+m. To a function f associate the spline function Vf of order m with knots Δ defined by(1.1)whereand the Nj(x) are B-splines with support xj < x < xj+m normalized so that ΣjNj(x) = 1. See, e.g., [2] for a precise definition of the Nj(x) and a discussion of the properties of Vf.

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31

Kusuma, Tiara Putri y Rati Aprianti. "PROFIL KEMAMPUAN LITERASI DIGITAL KELAS X, XI DAN XII PADA MATA PELAJARAN BIOLOGI DI TASIKMALAYA". Bioed : Jurnal Pendidikan Biologi 8, n.º 1 (21 de agosto de 2021): 39. http://dx.doi.org/10.25157/jpb.v8i1.5994.

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Penelitian ini bertujuan untuk melihat profil kemampuan literaai digital siswa kelas X, XI dan XII pada mata pelajaran Biologi di Tasikmalaya. Penelitian ini menggunakan pendekatan kuantitatif dengan format penelitian deskriptif. Populasi penelitian ini adalah seluruh siswa siswi kelas X, XI dan XII di Tasikmalaya tahun pelajaran 2019/2020 dengan jumlah sampel yang terkumpul sebanyak 121 yang terdiri dari 34 siswa kelas X, 52 siswa kelas XI dan 35 siswa kelas XII. Samping menggunakan Teknik stratified random sampling, yakni yang menjadi sampel adalah siswa kelas X , XI dan siswa kelas XII. Teknik pengumpulan data dalam penelitian ini dilakukan melalui kuesioner, observasi dan wawancara. Hasil temuan data disajikan kedalam 4 aspek sesuai dengan kuesioner yang telah disebarkan kepada para responden. Adapun empat aspek tersebut antara lain : pencarian di internet (internet searching), pandu arah hypertext (hypertextual navigation), evaluasi konten informasi (content evaluation), serta penyusunan pengetahuan (knowledge assembly). Oleh karena itu untuk kemampuan literasi digital di kelas X, XI dan XII pada mata pelajaran Biologi sudah tergolong tinggi dengan total skor rata-rata sebesar 5,40. Kata kunci : Kemampuan Literasi Digital, Deskriptif kuantitatif, Biologi

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32

Azkiya, Zikra y Hamzah Hamzah. "COMPARING STUDENTS’ ABILITY IN WRITING RECOUNT TEXT OF GRADE X AND GRADE XI AT SMAN 1 LUBUK ALUNG". Journal of English Language Teaching 9, n.º 1 (8 de marzo de 2020): 136. http://dx.doi.org/10.24036/jelt.v9i1.107886.

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This research was about the comparison between students’ ability of grade X and grade XI in writing recount text with the topic of an unforgettable experience. This study aimed to compare the level of students’ grade X and grade XI ability in writing recount text seen from the generic structure of the text. The research design of this study was descriptive research. The population of this research was all of classes grade X and grade XI of SMAN 1 Lubuk Alung. The sample was taken by using random cluster sampling technique so that the sample obtained was 1 class from grade X and 1 class from grade XI. The instrument used in this study was a test recount text for 45 minutes in at least 100 words. The students’ writing was analyzed using recount text writing rubric related to the generic structure of the text. Based on this research, students’ ability of grade XI was higher than grade X by looking from the generic structure of recount text. The ability of students grade XI was in 3 (good) category while students grade X was in 2 (weak) category. Nevertheless, there were several parts of the text that students could not understand yet how to write them.

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Achter, Jeffrey D. "THE DISTRIBUTION OF TORSION SUBSCHEMES OF ABELIAN VARIETIES". Journal of the Institute of Mathematics of Jussieu 15, n.º 4 (15 de diciembre de 2014): 693–710. http://dx.doi.org/10.1017/s1474748014000450.

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We consider the distribution of $p$-power group schemes among the torsion of abelian varieties over finite fields of characteristic $p$, as follows. Fix natural numbers $g$ and $n$, and let ${\it\xi}$ be a non-supersingular principally quasipolarized Barsotti–Tate group of level $n$. We classify the $\mathbb{F}_{q}$-rational forms ${\it\xi}^{{\it\alpha}}$ of ${\it\xi}$. Among all principally polarized abelian varieties $X/\mathbb{F}_{q}$ of dimension $g$ with $X[p^{n}]_{\bar{\mathbb{F}}_{q}}\cong {\it\xi}_{\bar{\mathbb{F}}_{q}}$, we compute the frequency with which $X[p^{n}]\cong {\it\xi}^{{\it\alpha}}$. The error in our estimate is bounded by $D/\sqrt{q}$, where $D$ depends on $g$, $n$, and $p$, but not on ${\it\xi}$.

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34

Bonora, Giancarlo y Christine M. Disteche. "Structural aspects of the inactive X chromosome". Philosophical Transactions of the Royal Society B: Biological Sciences 372, n.º 1733 (25 de septiembre de 2017): 20160357. http://dx.doi.org/10.1098/rstb.2016.0357.

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A striking difference between male and female nuclei was recognized early on by the presence of a condensed chromatin body only in female cells. Mary Lyon proposed that X inactivation or silencing of one X chromosome at random in females caused this structural difference. Subsequent studies have shown that the inactive X chromosome (Xi) does indeed have a very distinctive structure compared to its active counterpart and all autosomes in female mammals. In this review, we will recap the discovery of this fascinating biological phenomenon and seminal studies in the field. We will summarize imaging studies using traditional microscopy and super-resolution technology, which revealed uneven compaction of the Xi. We will then discuss recent findings based on high-throughput sequencing techniques, which uncovered the distinct three-dimensional bipartite configuration of the Xi and the role of specific long non-coding RNAs in eliciting and maintaining this structure. The relative position of specific genomic elements, including genes that escape X inactivation, repeat elements and chromatin features, will be reviewed. Finally, we will discuss the position of the Xi, either near the nuclear periphery or the nucleolus, and the elements implicated in this positioning. This article is part of the themed issue ‘X-chromosome inactivation: a tribute to Mary Lyon’.

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35

Abulhamil, Doha Adel, Fatmah B. Jamjoom y Antonio M. Peralta. "Linear Maps Which are Anti-derivable at Zero". Bulletin of the Malaysian Mathematical Sciences Society 43, n.º 6 (12 de marzo de 2020): 4315–34. http://dx.doi.org/10.1007/s40840-020-00918-7.

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Abstract Let $$T:A\rightarrow X$$ T : A → X be a bounded linear operator, where A is a $$\hbox {C}^*$$ C ∗ -algebra, and X denotes an essential Banach A-bimodule. We prove that the following statements are equivalent: (a) T is anti-derivable at zero (i.e., $$ab =0$$ a b = 0 in A implies $$T(b) a + b T(a)=0$$ T ( b ) a + b T ( a ) = 0 ); (b) There exist an anti-derivation $$d:A\rightarrow X^{**}$$ d : A → X ∗ ∗ and an element $$\xi \in X^{**}$$ ξ ∈ X ∗ ∗ satisfying $$\xi a = a \xi ,$$ ξ a = a ξ , $$\xi [a,b]=0,$$ ξ [ a , b ] = 0 , $$T(a b) = b T(a) + T(b) a - b \xi a,$$ T ( a b ) = b T ( a ) + T ( b ) a - b ξ a , and $$T(a) = d(a) + \xi a,$$ T ( a ) = d ( a ) + ξ a , for all $$a,b\in A$$ a , b ∈ A . We also prove a similar equivalence when X is replaced with $$A^{**}$$ A ∗ ∗ . This provides a complete characterization of those bounded linear maps from A into X or into $$A^{**}$$ A ∗ ∗ which are anti-derivable at zero. We also present a complete characterization of those continuous linear operators which are $$^*$$ ∗ -anti-derivable at zero.

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36

Badziahin, Dzmitry, Yann Bugeaud y Johannes Schleischitz. "On simultaneous rational approximation to a p-adic number and its integral powers, II". Proceedings of the Edinburgh Mathematical Society 64, n.º 2 (mayo de 2021): 317–37. http://dx.doi.org/10.1017/s001309152100016x.

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AbstractLet $p$ be a prime number. For a positive integer $n$ and a real number $\xi$, let $\lambda _n (\xi )$ denote the supremum of the real numbers $\lambda$ for which there are infinitely many integer tuples $(x_0, x_1, \ldots , x_n)$ such that $| x_0 \xi - x_1|_p, \ldots , | x_0 \xi ^{n} - x_n|_p$ are all less than $X^{-\lambda - 1}$, where $X$ is the maximum of $|x_0|, |x_1|, \ldots , |x_n|$. We establish new results on the Hausdorff dimension of the set of real numbers $\xi$ for which $\lambda _n (\xi )$ is equal to (or greater than or equal to) a given value.

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37

Dimitrijevic, M. S. y S. Sahal−Bréchot. "Stark broadening parameter tables for Sc X, Sc XI, Ti XI and Ti XII". Serbian Astronomical Journal, n.º 157 (1998): 39–64. http://dx.doi.org/10.2298/saj9857039d.

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By using the semiclassical-perturbation formalism, we have calculated electron-, proton-, and He III-impact line widths and shifts for 4 Sc X, 10 Sc XI, 4 Ti XI and 27 Ti XII multiplets, significant for investigation and modeling of different plasmas in astrophysics and physics. For Sc X calculations have been performed within the temperature range from 200,000 K to 5,000,000 K, and for perturber densities 1019cm?3 - 1022cm?3. Stark broadening data for Sc XI are tabulated for temperatures from 500,000 K to 5,000,000 K, and perturber densities 1018cm?3 - 1022cm?3. For Ti XI calculations were performed within the temperature range from 500,000 K to 5,000,000 K, and perturber densities 1018cm?3 - 1022cm?3, while for Ti XII results are given for temperatures from 500,000 K to 6,000,000 K, and perturber densities 1018cm?3 - 1023cm?3.

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38

Cantone, Irene y Amanda G. Fisher. "Human X chromosome inactivation and reactivation: implications for cell reprogramming and disease". Philosophical Transactions of the Royal Society B: Biological Sciences 372, n.º 1733 (25 de septiembre de 2017): 20160358. http://dx.doi.org/10.1098/rstb.2016.0358.

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X-chromosome inactivation (XCI) is an exemplar of epigenetic regulation that is set up as pluripotent cells differentiate. Once established, XCI is stably propagated, but can be reversed in vivo or by pluripotent reprogramming in vitro . Although reprogramming provides a useful model for inactive X (Xi) reactivation in mouse, the relative instability and heterogeneity of human embryonic stem (ES) cells and induced pluripotent stem cells hampers comparable progress in human. Here we review studies aimed at reactivating the human Xi using different reprogramming strategies. We outline our recent results using mouse ES cells to reprogramme female human fibroblasts by cell–cell fusion. We show that pluripotent reprogramming induces widespread and rapid chromatin remodelling in which the human Xi loses XIST and H3K27m3 enrichment and selected Xi genes become reactivated, ahead of mitotic division. Using RNA sequencing to map the extent of human Xi reactivation, and chromatin-modifying drugs to potentiate reactivation, we outline how this approach could be used to better design strategies to re-express human X-linked loci. As cell fusion induces the expression of human pluripotency genes that represent both the ‘primed’ and ‘naive’ states, this approach may also offer a fresh opportunity to segregate human pluripotent states with distinct Xi expression profiles, using single-cell-based approaches. This article is part of the themed issue ‘X-chromosome inactivation: a tribute to Mary Lyon’.

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39

Veis, Arthur y Elton Katz. "General Discussion for Sessions X and XI". Connective Tissue Research 21, n.º 1-4 (enero de 1989): 283–96. http://dx.doi.org/10.3109/03008208909050018.

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40

Editorial Office, CUAJ. "Sessions scientifiques VI, VIII, IX, X, XI". Canadian Urological Association Journal 6, n.º 6-S3 (1 de diciembre de 2012): 160. http://dx.doi.org/10.5489/cuaj.1478.

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41

Abbott, D. Wade, Brian P. Chadwick, Anita A. Thambirajah y Juan Ausió. "Beyond the Xi". Journal of Biological Chemistry 280, n.º 16 (17 de febrero de 2005): 16437–45. http://dx.doi.org/10.1074/jbc.m500170200.

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MacroH2A (mH2A) is a histone variant that is enriched in the inactivated X-chromosomes of mammalian females. To characterize the role of this protein in other nuclear processes we isolated chromatin particles from chicken liver, a vertebrate system that does not undergo X-inactivation. Chromatin digestion and fractionation studies determined that mH2A is evenly distributed at several levels of chromatin structure and stabilizes the nucleosome core particle in solution. However, at the level of the chromatosome, selective salt precipitation showed the existence of a mutually exclusive relationship between mH2A and H1, which may reveal functional redundancy between these proteins. Two-dimensional gel electrophoresis demonstrated the presence of one major population of mH2A containing nucleosomes, which may become ADP-ribosylated. This report provides new clues into how mH2A distribution and a previously unidentified post-translational modification may help regulate the repression of autosomal chromatin.

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42

Przanowski, Piotr, Urszula Wasko, Zeming Zheng, Jun Yu, Robyn Sherman, Lihua Julie Zhu, Michael J. McConnell, Jogender Tushir-Singh, Michael R. Green y Sanchita Bhatnagar. "Pharmacological reactivation of inactive X-linked Mecp2 in cerebral cortical neurons of living mice". Proceedings of the National Academy of Sciences 115, n.º 31 (16 de julio de 2018): 7991–96. http://dx.doi.org/10.1073/pnas.1803792115.

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Rett syndrome (RTT) is a genetic disorder resulting from a loss-of-function mutation in one copy of the X-linked gene methyl-CpG–binding protein 2 (MECP2). Typical RTT patients are females and, due to random X chromosome inactivation (XCI), ∼50% of cells express mutant MECP2 and the other ∼50% express wild-type MECP2. Cells expressing mutant MECP2 retain a wild-type copy of MECP2 on the inactive X chromosome (Xi), the reactivation of which represents a potential therapeutic approach for RTT. Previous studies have demonstrated reactivation of Xi-linked MECP2 in cultured cells by biological or pharmacological inhibition of factors that promote XCI (called “XCI factors” or “XCIFs”). Whether XCIF inhibitors in living animals can reactivate Xi-linked MECP2 in cerebral cortical neurons, the cell type most therapeutically relevant to RTT, remains to be determined. Here, we show that pharmacological inhibitors targeting XCIFs in the PI3K/AKT and bone morphogenetic protein signaling pathways reactivate Xi-linked MECP2 in cultured mouse fibroblasts and human induced pluripotent stem cell-derived postmitotic RTT neurons. Notably, reactivation of Xi-linked MECP2 corrects characteristic defects of human RTT neurons including reduced soma size and branch points. Most importantly, we show that intracerebroventricular injection of the XCIF inhibitors reactivates Xi-linked Mecp2 in cerebral cortical neurons of adult living mice. In support of these pharmacological results, we also demonstrate genetic reactivation of Xi-linked Mecp2 in cerebral cortical neurons of living mice bearing a homozygous XCIF deletion. Collectively, our results further establish the feasibility of pharmacological reactivation of Xi-linked MECP2 as a therapeutic approach for RTT.

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43

Zhao, Shiliang. "Centered Hardy-Littlewood maximal function on product manifolds". Advances in Nonlinear Analysis 11, n.º 1 (1 de enero de 2022): 888–906. http://dx.doi.org/10.1515/anona-2021-0233.

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Abstract Let X be the direct product of Xi where Xi is smooth manifold for 1 ≤ i ≤ k. As is known, if every Xi satisfies the doubling volume condition, then the centered Hardy-Littlewood maximal function M on X is weak (1,1) bounded. In this paper, we consider the product manifold X where at least one Xi does not satisfy the doubling volume condition. To be precise, we first investigate the mapping properties of M when X 1 has exponential volume growth and X 2 satisfies the doubling condition. Next, we consider the product space of two weighted hyperbolic spaces X 1 = (ℍ n+1, d, yα −n−1 dydx) and X 2 = (ℍ n+1, d, yβ −n−1 dydx) which both have exponential volume growth. The mapping properties of M are discussed for every α , β ≠ n 2 \alpha,\beta \ne {n \over 2} . Furthermore, let X = X 1 × X 2 × … Xk where Xi = (ℍ ni +1, yαi − ni −1 dydx) for 1 ≤ i ≤ k. Under the condition α i > n i 2 {\alpha_i} > {{{n_i}} \over 2} , we also obtained the mapping properties of M.

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44

Boldyreva, I. I. "Woman as Offender in the Anglo-Saxon Society of X–XI Centuries". Izvestiya of Saratov University. New Series. Series: History. International Relations 18, n.º 4 (2018): 445–50. http://dx.doi.org/10.18500/1819-4907-2018-18-4-445-450.

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45

Jonkers, Iris, Kim Monkhorst, Eveline Rentmeester, J. Anton Grootegoed, Frank Grosveld y Joost Gribnau. "Xist RNA Is Confined to the Nuclear Territory of the Silenced X Chromosome throughout the Cell Cycle". Molecular and Cellular Biology 28, n.º 18 (14 de julio de 2008): 5583–94. http://dx.doi.org/10.1128/mcb.02269-07.

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ABSTRACT In mammalian female cells, one X chromosome is inactivated to prevent a dose difference in the expression of X-encoded proteins between males and females. Xist RNA, required for X chromosome inactivation, is transcribed from the future inactivated X chromosome (Xi), where it spreads in cis, to initiate silencing. We have analyzed Xist RNA transcription and localization throughout the cell cycle. It was found that Xist transcription is constant and that the mature RNA remains attached to the Xi throughout mitosis. Diploid and tetraploid cell lines with an MS2-tagged Xist gene were used to investigate spreading of Xist. Most XXXXMS2 tetraploid mouse embryonic stem (ES) cells inactivate the XMS2 chromosome and one other X chromosome. Analysis of cells with two Xi's indicates that Xist RNA is retained by the Xi of its origin and does not spread in trans. Also, in XXMS2 diploid mouse ES cells with an autosomal Xist transgene, there is no trans exchange of Xist RNA from the Xi to the autosome. We propose that Xist RNA does not dissociate from the Xi of its origin, which precludes a model of diffusion-mediated trans spreading of Xist RNA.

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46

Diamond, J. R. y I. Pesek-Diamond. "Sublethal X-irradiation during acute puromycin nephrosis prevents late renal injury: role of macrophages". American Journal of Physiology-Renal Physiology 260, n.º 6 (1 de junio de 1991): F779—F786. http://dx.doi.org/10.1152/ajprenal.1991.260.6.f779.

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Acute puromycin aminonucleoside (PA) nephrosis is associated with a surge in the glomerular macrophage number. Whole body X-irradiation (XI) was used to assess whether bone marrow depression, which depletes normal rat glomeruli of macrophages, is efficacious in ameliorating progressive glomerular disease. A solitary, sublethal dose of XI (600 rad) was administered 3 days after PA delivery to rats (PA/XI) that were followed for 18 wk. In contrast to a sham-irradiated nephrotic cohort (PA/Sham), the PA/XI rats had a complete prevention of the recurrent albuminuria and manifested a significant reduction in the percent of glomeruli exhibiting glomerulosclerosis (GS) lesions at 18 wk after PA. XI significantly reduced the glomerular and interstitial macrophage number as well as the circulating white blood and monocyte counts during peak albuminuria. This protection was independent of the magnitude of the acute albuminuria and elevations in the circulating lipid levels. These data show that whole body XI delivered during acute nephrosis is capable of preventing progressive glomerular disease in association with a reduction in the glomerular and interstitial macrophage number. Additionally, this study suggests that this immune effector cell is important in mediating the propagation of initial glomerular injury to GS.

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47

Clop, Albert, Raffaella Giova, Farhad Hatami y Antonia Passarelli di Napoli. "Very degenerate elliptic equations under almost critical Sobolev regularity". Forum Mathematicum 32, n.º 6 (1 de noviembre de 2020): 1515–37. http://dx.doi.org/10.1515/forum-2020-0058.

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AbstractWe prove the local Lipschitz continuity and the higher differentiability of local minimizers of functionals of the form\mathbb{F}(u,\Omega)=\int_{\Omega}(F(x,Du(x))+f(x)\cdot u(x))\mathop{}\!dxwith non-autonomous integrand {F(x,\xi)} which is degenerate convex with respect to the gradient variable. The main novelty here is that the results are obtained assuming that the partial map {x\mapsto D_{\xi}F(x,\xi)} has weak derivative in the almost critical Zygmund class {L^{n}\log^{\alpha}L} and the datum f is assumed to belong to the same Zygmund class.

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48

Cellina, Arrigo. "On the regularity of solutions to the plastoelasticity problem". Advances in Calculus of Variations 13, n.º 1 (1 de enero de 2020): 1–14. http://dx.doi.org/10.1515/acv-2017-0004.

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AbstractWe prove the local regularity of solutions to the problem of minimizing\int_{\Omega}\bigl{[}L_{\infty}(\nabla v(x))+f(x)v(x)\bigr{]}\,dx\quad\text{on% }u^{0}+W^{1,\infty}_{0}(\Omega),where {L_{\infty}} is either {\frac{1}{2}\lvert\xi\rvert^{2}} for {\lvert\xi\rvert\leq 1} and {+\infty} for {\lvert\xi\rvert>1}, or a more general convex, extended-valued function.

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49

Baliunas, Sallie L., Yoji Kondo, Norio Kaifu, Oddbjørn Engvold, Norio Kaifu, Haruyuki Okuda y Yervant Terzian. "INTER-DIVISION IX-X-XI WORKING GROUP ASTRONOMY FROM THE MOON". Proceedings of the International Astronomical Union 4, T27A (diciembre de 2008): 356. http://dx.doi.org/10.1017/s1743921308025842.

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During the period the Working Group had proposed and was granted renewed status by Division XI Space and High-Energy Astrophysics. Additionally the Working Group requested to be extended to Division IX Optical and Infrared Techniques, Division X Radio Astronomy, as well as Division XI.

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50

Zulfatul Muhasanah, Lia. "Perbedaan Gaya Mengajar Guru Laki-Laki dan Perempuan dalam Mengembangkan Minat Belajar Siswa pada Mata Pelajaran Rumpun Pendidikan Agama Islam di Kelas X dan Xi Madrasah Aliyah Negeri 2 Jember Tahun Ajaran 2017/2018". Auladuna : Jurnal Prodi Pendidikan Guru Madrasah Ibtidaiyah 2, n.º 2 (18 de enero de 2021): 92–124. http://dx.doi.org/10.36835/au.v2i2.423.

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Penelitian ini berusaha mengungkapkan pokok permasalahan mengenai, a). Adakah perbedaan gaya mengajar guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAIdikelas X dan XI MAN 2 Jember tahun pelajaran 2017/2018. Dan sub spokok masalahnya a). Adakah perbedaan gaya mengajar klasik guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI di MAN 2 Jember tahun pelajaran 2017/2018. b). Adakah perbedaan gaya mengajar teknologis guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI di MAN 2 Jember tahun pelajaran 2017/2018. c). Adakah perbedaan gaya mengajar personalisasi guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI di MAN 2 Jember tahun pelajaran 2017/2018. d). Adakah perbedaan gaya mengajar interaksional guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI di MAN 2 Jember tahun pelajaran 2017/2018. Dalam penelitian ini menggunakan pendekatan kuantitatif dengan jenis penelitian komparasi. Teknik pengambilan sampel menggunakan cluster random sampling dan instrumen pengumpulan data menggunakan observasi, wawancara, dan dokumentasi. Peneliti menggunakan analisis uji sampel t test. Hasil analisis data diperoleh kesimpulan umum: a). Tidak ada perbedaan gaya mengajar guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI MAN 2 Jember tahun pelajaran 2017/2018. Kesimpulan khusus: a). Tidak ada perbedaan gaya mengajar klasik guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI MAN 2 Jember tahun pelajaran 2017/2018. b). Tidak ada perbedaan gaya mengajar teknologis guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI MAN 2 Jember tahun pelajaran 2017/2018.c). Ada perbedaan gaya mengajar personalisasi guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI MAN 2 Jember tahun pelajaran 2017/2018. d). Tidak ada perbedaan gaya mengajar interaksional guru laki-laki dan perempuan dalam mengembangkan minat belajar siswa pada mata pelajaran rumpun PAI dikelas X dan XI MAN 2 Jember tahun pelajaran 2017/2018.

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