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Background The prevalence of Vitamin D deficiency remains high in cystic fibrosis despite daily supplementation. Vitamin D as an immunomodulator has been related to lower respiratory tract infections in children. The present study was undertaken to examine the association between vitamin D status and markers of cystic fibrosis-related pulmonary disease including exacerbations, bacterial colonization and pulmonary function. Methods The study includes review of records of 51 cystic fibrosis patients. Baseline patient variables and serum vitamin D levels were recorded. Based on vitamin D levels study patients were divided into three groups: vitamin-D sufficient (≥20 ng/mL), vitamin-D insufficient (12 to 20 ng/mL), and vitamin D-deficient (≤12 ng/ml). Results The proportion of children with deficient, insufficient and sufficient vitamin D levels were 47.1%, 15.7%, and 37.2%, respectively. Female sex, bacterial colonization and a greater number of exacerbations were associated with highest odds of developing vitamin D deficiency in patients with CF with 1.77 (0.22–4.61) (p = 0.002), 2.9(0.57−14.82) (p = 0.011), and 5.12 (1.28−20.50) (p = 0.021) respectively. The comparison of vitamin-D levels taken during exacerbations, colonization and during routine follow-up were significant [16.04 (7.42−27.91), 24.3 (15.5−32.4) and 48.54 (18.37−78.7) ng/ml, p < 0.001]. The FEV1 was determined in 24 patients; the comparison was significant between vitamin D-deficient and -sufficient groups [0.75 (0.717−0.777) vs. 0.82 (0.74−0.92) p < 0.05]. Conclusion We concluded that vitamin D deficiency was highly prevalent in children with CF, despite daily supplementation of the vitamin in diet. Further, vitamin D deficiency was associated with a higher rate of pulmonary exacerbations and higher incidence of pulmonary bacterial colonization. In addition, in younger patients, low vitamin D levels were associated with reduced pulmonary function. [ABSTRACT FROM AUTHOR]

Schematic representation of Isostatic balance between source and sink distribution of sediments and tectonics. [Display omitted] • The NSCSM evolved and linked with successive uplifts in SE Tibet Plateau. • Deep and surface parameters isostatically influence sediments and control their geometry. • Strengthening of lithosphere at the continental margin isostatically balanced with inland exhumation. Tectonic processes of the SE Tibet Plateau (SETP) and the northern South China Sea margin (NSCSM) strongly affected the surface drainage system for sediment transportation to deposition. It remains challenging to investigate the dominant mechanisms such as tectonics, deep dynamics, and surface processes. This paper aims to examine the influence of the SETP paleogeography on the NSCSM. Twenty-eight seismic profiles were quantified by flexurally interpolated backstripping and significantly correlated with the published paleogeography. A numerical simulation tool (Badlands) is assigned to study the integrated response of surface processes and deep dynamics. This paper inferred that drastic sedimentation changes in our models were linearly correlated mainly with erosion during the SETP uplifts, dynamic topography, and flexural isostasy. Deep dynamics and tectonic processes control basin architectures for sediment depositions, whereas the surface processes contribute isostatically in response to uplifts in the source region. We inferred that Eocene was the stage of extension, thinning of lithosphere (Te = 10 km) that is linked with the low topography (<2000 m) and erodibility (Є) of 5e-7 in the SETP. However, the increase in cumulative thickness is associated with strengthening the lithosphere (Te = 15 km) and tributary rotation with its rise in SETP topography (≥4000 m) during the Oligocene to Early Miocene. The Middle Miocene doesn't have the source-sink linkage for its high SETP topography with low deposition. But a strong connection with paleogeographic evolution in the later stage due to the rise in SETP topography and Taiwan orogeny. [ABSTRACT FROM AUTHOR]

The Cu-Sb-Pb polymetallic vein deposit is hosted by metavolcanics rocks of the Gawuch Formation at the Kaldom Gol area of the northwest Kohistan arc terrain in northern Pakistan. The mineralization is closely associated with the dioritic to granodioritic rocks of the Lowari pluton, which was intruded into the Gawuch metavolcanics. Details of ore characterization and processes of ore genesis of this evidently hydrothermal mineralization are not well documented. Integrating petrographic, mineral-chemical and isotopic investigations, this study aims to comprehend the source of hydrothermal fluids, geochemical evolution, mineral inclusions and physicochemical conditions of the Cu-Sb-Pb polymetallic vein deposit in Gawuch metavolcanics in the Kohistan arc terrain in northern Pakistan. The mineralization is distinguished into three types of ore-gangue associations: Type Ia, Type Ib, and Type II. The textural study revealed two pyrite generations: (i) Py1 displaying euhedral to subhedral habits and containing scarce inclusions, and (ii) Py2 occurring as anhedral grains hosting abundant inclusions. Type Ia is characterized by Py1 associated with abundant quartz (Qz) showing comb texture, sericite (Ser), and minor chlorite (Chl). Type Ib comprises Qz + Ser + Chl and Py2, chalcopyrite (Ccp), and magnetite (Mag). Type II is represented by mosaic quartz, rhombic adularia, and bladed calcite, and the ore minerals fahlore and galena. Alteration zones composed of Qz-Ser ± Chl and Qz-Ser-Chl, surround Type I (a, b) and Type II veins, respectively. Fahlore and galena mostly replace pyrite of Type Ia and chalcopyrite of Type Ib. In addition, malachite, azurite, hematite and covellite occur as secondary (supergene) minerals. The Co/Ni ratios (>1) of Kaldom Gol pyrites suggest that the ore-forming fluids were hydrothermal in origin and Py1 and Py2 solidified at 221–304 °C and 225–261 °C, respectively. The LA-ICP-MS time-resolved depth profiles confirm the existence of sphalerite, and chalcopyrite inclusions in pyrite (Py1 and Py2) and millerite , bravoite , vaesite , Au-tellurides, native Au and galena inclusions in chalcopyrite and fahlore. Sulfur isotope compositions of pyrites (δ34S = Py1, −0.58 to +2 ‰; δ34S = Py2, −0.24 to +2.04 ‰) indicate that the ore-forming fluids were derived from magmatic source (s). The mineral assemblage, hydrothermal alterations, textures, temperature and δ34S of pyrites suggest that the Cu-Sb-Pb polymetallic mineralization at Kaldom Gol represents an intermediate-sulfidation type of epithermal deposit. [Display omitted] [ABSTRACT FROM AUTHOR]

• The continental margin of SCS evolved through differential stretching and paleogeography. • Flexural interpolation of sparsely distributed data can provide excellent subsidence evolution. • Coevality of uplift in a basin make the sediment rates inconsistent with subsidence. • Stress directions, paleogeography, and differential crust relocate the sediments geometry. • Accumulation of thick deposits insight into the highly stretched and mechanically weak zones. The South China Sea (SCS) is the largest marginal sea on the SE Asian continental margin, located at the junction of the Pacific, Indo-Australia and Eurasian plates, and has undergone the joint effect of the Tethys and Pacific tectonic domains. Currently, the SCS remains debatable for its evolution and origin. However, its northern margin preserves the Cenozoic tectonic and subsidence history, which allow us to restore the past continental margin (0–33.7 Ma), to estimate subsidence, thickness and sediment accumulation correlated with regional tectonics. This paper has employed a 2D flexural backstripping technique and spatio-temporal variations by enhancing the seismic profiles with flexurally interpolated modelled sections. According to our findings, the transition was mainly controlled by three structural stages. (1) Early-Late Oligocene: records the highest subsidence due to the initiation of seafloor spreading, isostatic response of continental breakup, associated uplifts therein, and retreat of the Pacific Plate. (2) Early-Middle Miocene: mature spreading attributed to a slow phase of subsidence during the Early Miocene and a rapid increase of subsidence associated with the closure of the SCS in the Middle Miocene. (3) Thermal subsidence: sediments shifted since the Late Miocene towards mechanically weak and stretched regions (central-southern and eastern) which were triggered by a gravitational pull force. A fault system and differential stretched crust relocated sediment to the regional stress directions of the Pacific Plate. [ABSTRACT FROM AUTHOR]