Small planets transiting bright nearby stars are essential to our understanding of the formation and evolution of exoplanetary systems. However, few constitute prime targets for atmospheric ...characterization, and even fewer are part of multiple star systems. This work aims to validate TOI-4336 A b, a sub-Neptune-sized exoplanet candidate identified by the TESS space-based transit survey around a nearby M-dwarf. We validate the planetary nature of TOI-4336 A b through the global analysis of TESS and follow-up multi-band high-precision photometric data from ground-based telescopes, medium- and high-resolution spectroscopy of the host star, high-resolution speckle imaging, and archival images. The newly discovered exoplanet TOI-4336 A b has a radius of 2.1\(\pm\)0.1R\(_{\oplus}\). Its host star is an M3.5-dwarf star of mass 0.33\(\pm\)0.01M\(_{\odot}\) and radius 0.33\(\pm\)0.02R\(_{\odot}\) member of a hierarchical triple M-dwarf system 22 pc away from the Sun. The planet's orbital period of 16.3 days places it at the inner edge of the Habitable Zone of its host star, the brightest of the inner binary pair. The parameters of the system make TOI-4336 A b an extremely promising target for the detailed atmospheric characterization of a temperate sub-Neptune by transit transmission spectroscopy with JWST.
The field of spinal cord MRI is lacking a common template, as existing for the brain, which would allow extraction of multi-parametric data (diffusion-weighted, magnetization transfer, etc.) without ...user bias, thereby facilitating group analysis and multi-center studies. This paper describes a framework to produce an unbiased average anatomical template of the human spinal cord. The template was created by co-registering T2-weighted images (N=16 healthy volunteers) using a series of pre-processing steps followed by non-linear registration. A white and gray matter probabilistic template was then merged to the average anatomical template, yielding the MNI–Poly–AMU template, which currently covers vertebral levels C1 to T6. New subjects can be registered to the template using a dedicated image processing pipeline. Validation was conducted on 16 additional subjects by comparing an automatic template-based segmentation and manual segmentation, yielding a median Dice coefficient of 0.89. The registration pipeline is rapid (~15min), automatic after one C2/C3 landmark manual identification, and robust, thereby reducing subjective variability and bias associated with manual segmentation. The template can notably be used for measurements of spinal cord cross-sectional area, voxel-based morphometry, identification of anatomical features (e.g., vertebral levels, white and gray matter location) and unbiased extraction of multi-parametric data.
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•First unbiased template of the human spinal cord: MNI–Poly–AMU•Probabilistic atlas of white and gray matter•Framework for registering data to the template (T1, T2, DTI, fMRI, MTR, etc.)•Open source software, actively maintained
A reply to Noretta Koertge (1999) argues that his A House Built on Sand (1998) does not refute the findings of the sociology of scientific knowledge case studies examined. Rather, the book serves to ...bolster the beliefs of parties already critical of the sociology of science knowledge. It is suggested that philosophers of science, such as Koertge, & sociologists of scientific knowledge cooperate to produce more informed justifications of science. 1 Table. J. Ferrari
Calls for sociologists of knowledge to be committed to their subjects are examined critically. The idea of 'commitment to commitment' is shown to be based either on fallacious reasoning or on a ...disguised call for commitment to the author's favoured causes. The 'universal' and 'local inevitability' arguments are analyzed and shown to be wrong. The former suggests that every scientific claim includes a commitment, willy-nilly; the latter says that analysts will be 'captured', whether they like it or not. A particular case of the reception of a case study of a controversy is described; the reception of this case went against expectations, and some speculations are offered about the cause. Instances where the subject of a sociological study is also the object of study are looked at. Finally, good reasons for commitment are set out: one thing that the sociologist of science should engage in is 'analytic critique of science', and this involves commitment.
Oestrogen-replacement therapy is associated with a reduced incidence of cardiovascular disease. The acute administration of oestrogen improves myocardial ischemia in women with coronary heart ...disease. In this study we investigated the relaxing effect of oestradiol-17 beta on human coronary arteries in vitro and determined the role of endothelial modulation in this relaxation by using isolated human coronary arteries.
Atherosclerosis-free epicardial arteries from men and women were removed from patients undergoing heart or combined heart and lung transplantation. The arteries were cut into ring segments and placed into organ baths containing Tyrode's solution. Changes in isometric tension were measured. The relaxing response to oestradiol-17 beta (10(-10) - 10(-5) mol/l) was investigated and the effects of endothelium, NGmonomethyl-L-arginine and indomethacin on the response of oestradiol-17 beta were assessed.
Oestradiol-17 beta (10(-10) - 10(-5) mol/l) induced significant relaxation in coronary arteries pre-contracted with the thromboxane A2 analog (U46619; 3 x 10(-8) mol/l). Relaxation was significantly greater in coronary arteries from female patients. No significant differences were observed between arteries with or without endothelium nor after nitric oxide synthase or cyclo-oxygenase inhibition. These results indicate that oestradiol-17 beta induces human coronary artery relaxation via an endothelium-independent mechanism in vitro. The sex of the patients significantly affects sensitivity of the coronary arterial rings to oestrogen.
Oestradiol-17 beta-induced coronary relaxation may play an important role in regulation of coronary tone, and may partly explain why oestrogen improves myocardial ischemia in women and why it protects postmenopausal women from the risk of developing coronary heart disease.
Chronic granulomatous disease (CGD) results from defects in the phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, central to which is the membrane-bound cytochrome b-245. The ...cytochrome is composed of two protein subunits, the larger (gp91-phox) being deficient in X-linked CGD. In this study, we have analyzed expression of the cytochrome subunits in B-cell lines from two autosomal CGD patients for whom the disease is caused by deficiency of p22-phox, the smaller subunit. We report the presence of a 65-kD precursor of gp91-phox in the membrane fraction of both p22-phox-deficient cell lines, corresponding to the core protein with N-linked carbohydrate side chains in the high mannose form. Expression of p22-phox in these cells resulted in functional correction of NADPH oxidase. In addition, gp91-phox in the reconstituted cells was processed to its terminally glycosylated form. These data suggest that the association of the 65-kD gp91-phox precursor with p22-phox is a prerequisite for processing of the carbohydrate side chains to the complex form in the Golgi. The detection of this precursor will enable characterization of mutations disrupting the subunit interaction (either naturally occurring or derived by in vitro mutagenesis) and so aid in structure-function analysis of cytochrome b-245. Reconstitution of p22-phox-deficient cells shows the potential of gene therapy for this autosomal form of CGD.
Results are presented for the first measurement of the double-polarization helicity asymmetry E for the η photoproduction reaction γ p → η p. Data were obtained using the FROzen Spin Target (FROST) ...with the CLAS spectrometer in Hall B at Jefferson Lab, covering a range of center-of-mass energy W from threshold to 2.15 GeV and a large range in center-of-mass polar angle. As an initial application of these data, the results have been incorporated into the J\"ulich model to examine the case for the existence of a narrow Ν* resonance between 1.66 and 1.70 GeV. The addition of these data to the world database results in marked changes in the predictions for the E observable using that model. As a result, further comparison with several theoretical approaches indicates these data will significantly enhance our understanding of nucleon resonances.
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