The RS Oph outburst of 2021 monitored in X-rays with NICER

The 2021 outburst of the symbiotic recurrent nova RS Oph was monitored with the Neutron Star Interior Composition Explorer Mission (NICER) in the 0.2-12 keV range from day one after the optical maximum, until day 88, producing an unprecedented, detailed view of the outburst development. The X-ray flux preceding the supersoft X-ray phase peaked almost 5 days after optical maximum and originated only in shocked ejecta for 21 to 25 days. The emission was thermal; in the first 5 days only a non-collisional-ionization equilibrium model fits the spectrum, and a transition to equilibrium occurred between days 6 and 12. The ratio of peak X-rays flux measured in the NICER range to that measured with Fermi in the 60 MeV-500 GeV range was about 0.1, and the ratio to the peak flux measured with H.E.S.S. in the 250 GeV-2.5 TeV range was about 100. The central supersoft X-ray source (SSS), namely the shell hydrogen burning white dwarf (WD), became visible in the fourth week, initially with short flares. A huge increase in flux occurred on day 41, but the SSS flux remained variable. A quasi-periodic oscillation every ~35 s was always observed during the SSS phase, with variations in amplitude and a period drift that appeared to decrease in the end. The SSS has characteristics of a WD of mass >1 M(solar). Thermonuclear burning switched off shortly after day 75, earlier than in 2006 outburst. We discuss implications for the nova physics.Comment: Accepted for publication in the Astrophysical Journa

An Interesting Class of Porous Polymer-Revisiting the Structure of Mesoporous α-d-Polysaccharide Gels

The processes involved in the transformation of non-porous, native polysaccharides to their highly porous equivalents introduce significant molecular complexity and are not yet fully understood. In this paper, we propose that distinct changes in polysaccharide local short-range ordering promotes and directs the formation of meso- and micro-pores, which are investigated here using N2 sorption, FTIR, and solid-state 13CNMR. It is found that an increase in the overall double helical amylose content, and their local association structures, are responsible for formation of the porous polysaccharide gel phase. An exciting consequence of this local ordering change is elegantly revealed using a 19FNMR experiment, which identifies the stereochemistry-dependent diffusion of a fluorinated chiral probe molecule (1-phenyl-2,2,2-trifluoroethanol) from the meso- to the micro-pore region. This finding opens opportunities in the area of polysaccharide-based chiral stationary phases and asymmetric catalyst preparation

Functional Fluorescent Ca(2+) Indicator Proteins in Transgenic Mice under TET Control

Genetically encoded fluorescent calcium indicator proteins (FCIPs) are promising tools to study calcium dynamics in many activity-dependent molecular and cellular processes. Great hopes—for the measurement of population activity, in particular—have therefore been placed on calcium indicators derived from the green fluorescent protein and their expression in (selected) neuronal populations. Calcium transients can rise within milliseconds, making them suitable as reporters of fast neuronal activity. We here report the production of stable transgenic mouse lines with two different functional calcium indicators, inverse pericam and camgaroo-2, under the control of the tetracycline-inducible promoter. Using a variety of in vitro and in vivo assays, we find that stimuli known to increase intracellular calcium concentration (somatically triggered action potentials (APs) and synaptic and sensory stimulation) can cause substantial and rapid changes in FCIP fluorescence of inverse pericam and camgaroo-2

The Islamic Law in the Historical Study

Dalam kajian tentang sejarah awal Islam dan agama di dunia Barat, Islam dipandang sebagai agama \u27\u27dalam sejarab". Melaiui pandangan ini, para sarjana mempelajari sejarah awal Islam, di antaranya, dengan menggunakan meiode analisa kritik terbadap sumber-sumber sejarah termasuk kepusiakaan selain Islam dijadikan sebagai sumber dan bukti sejarah. Sejak itu pula hukum Islam dikaji melaiui pendekatan yang sama. Melaiui pendekatan ini diyakini bahwa hukum Islam mengandung tradisi-tradisi keagamaan khususnya di wilayab limur dekat yang ada sebeium Islam, dan dipandang sebagai suatu perkembangan yang berkelanjutan. Sebagaimana hasii kajian daripada Patricia Crone dan Gordon D. Newby menunjukkan bahwa di antara tradisi-tradisi keagamaan dimaksud, saiah satunya, adalab hukum Yahudi. Crone memberikan contoh qasama khususnya yang ada pada mazhab Maiiki dan mengktaim bahwa qasama dimaksud merupakan salah satu tradisi hukum yang ada pada orang-orang Yahudi. Sedangkan Newby memberikan contoh tentang penentuan orang band sebagai laki-iaki atau sebagai perempuan dalam hubungannya dengan pembagian kewarisan yang ada pada catatan \u27Amirb. Zarib di daiam sirah Ibnu Ishaq, dan mengktaim juga bahwa catatan tersebut berasai dari hukum Yahudi. Sebaliknya, pendekatan ini merupakan salah satu pendekatan yang ada dalam kajian hukum Islam dan sangat baik dipakai untuk mencari keseimhangan dan menunjukkan bahwa walaupun terdapat kesamaan antara hukum Islam dengan hukum-hukum yang lain, proses sejarab perkembangan hukum Islam itu sendiri sangat berbeda dan mempunyai karakteryang khusu

PLoS Pathog

Cytomegalovirus (CMV) is a leading infectious cause of morbidity in immune-compromised patients. γδ T cells have been involved in the response to CMV but their role in protection has not been firmly established and their dependency on other lymphocytes has not been addressed. Using C57BL/6 αβ and/or γδ T cell-deficient mice, we here show that γδ T cells are as competent as αβ T cells to protect mice from CMV-induced death. γδ T cell-mediated protection involved control of viral load and prevented organ damage. γδ T cell recovery by bone marrow transplant or adoptive transfer experiments rescued CD3ε-/- mice from CMV-induced death confirming the protective antiviral role of γδ T cells. As observed in humans, different γδ T cell subsets were induced upon CMV challenge, which differentiated into effector memory cells. This response was observed in the liver and lungs and implicated both CD27+ and CD27- γδ T cells. NK cells were the largely preponderant producers of IFNγ and cytotoxic granules throughout the infection, suggesting that the protective role of γδ T cells did not principally rely on either of these two functions. Finally, γδ T cells were strikingly sufficient to fully protect Rag-/-γc-/- mice from death, demonstrating that they can act in the absence of B and NK cells. Altogether our results uncover an autonomous protective antiviral function of γδ T cells, and open new perspectives for the characterization of a non classical mode of action which should foster the design of new γδ T cell based therapies, especially useful in αβ T cell compromised patients