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1.
Heliyon ; 9(12): e22896, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38076059

ABSTRACT

Background: Different biomarkers have been suggested as novel biomarkers of coronavirus disease 2019 (COVID-19) theragnosis. With the aim of having a better clinical management of COVID-19, we decided to determine the relationship between hematological, inflammatory, and novel biomarkers with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immunoglobulin (Ig)M and IgG antibodies. Methods: Blood samples from 127 confirmed COVID-19 patients aged 11-84 years old were collected and tested for SARS-CoV-2 IgM and IgG antibodies alongside with hematological, inflammatory, and novel biomarkers. The Spearman correlation test was utilized to analyze the correlation between these biomarkers with SARS-CoV-2 IgM and IgG antibodies. Results: The SARS-CoV-2 IgM antibody significantly correlated with erythrocyte sedimentation rate (ESR) (r = 0.329, p = 0.000), C-reactive protein (CRP) (r = 0.459, p = 0.000), interleukin (IL)-6 (r = 0.345, p = 0.000), IL-8 (r = 0.263, p = 0.003), neutrophil to lymphocyte ratio (NLR) (r = 0.182, p = 0.040), derived NLR (dNLR) (r = 0.197, p = 0.026), neutrophil to monocyte ratio (NMR) (r = 0.184, p = 0.038), and CRP to lymphocyte ratio (CLR) (r = 0.495, p = 0.000). Also, we find significant correlation between SARS-CoV-2 IgG antibody with hemoglobin (Hb) (r = -0.257, p = 0.004), hematocrit (Hct) (r = -0.227, p = 0.010), mean corpuscular Hb concentration (MCHC) (r = -0.212, p = 0.017), lymphocyte count (r = -0.211, p = 0.017), platelet count (r = 0.179, p = 0.044), ESR (r = 0.461, p = 0.000), CRP (r = 0.344, p = 0.000), IL-6 (r = 0.178, p = 0.046), IL-8 (r = 0.237, p = 0.007), platelet to lymphocyte ratio (PLR) (r = 0.295, p = 0.001), and CLR (r = 0.376, p = 0.000). Conclusion: Hematological biomarkers (Hb, Hct, MCHC, lymphocyte count, and platelet count), inflammatory biomarkers (ESR, CRP, IL-6, and IL-8), and novel biomarkers (dNLR, NLR, NMR, PLR, and CLR) are valuable indicators for clinical management of COVID-19.

2.
Membranes (Basel) ; 12(6)2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35736325

ABSTRACT

A higher density of large-angle grain boundaries in palladium membranes promotes hydrogen diffusion whereas small-angle grain boundaries suppress it. In this paper, the microstructure formation in 10 µm thick palladium membranes is tuned to achieve a submicronic grain size above 100 nm with a high density of large-angle grain boundaries. Moreover, changes in the grain boundaries' structure is investigated after exposure to hydrogen at 300 and 500 °C. To attain large-angle grain boundaries in Pd, the coating was performed on yttria-stabilized zirconia/porous Crofer 22 APU substrates (intended for use later in an ultracompact membrane reactor). Two techniques of plasma sprayings were used: suspension plasma spraying using liquid nano-sized powder suspension and vacuum plasma spraying using microsized powder as feedstock. By controlling the process parameters in these two techniques, membranes with a comparable density of large-angle grain boundaries could be developed despite the differences in the fabrication methods and feedstocks. Analyses showed that a randomly oriented submicronic structure could be attained with a very similar grain sizes between 100 and 500 nm which could enhance hydrogen permeation. Exposure to hydrogen for 72 h at high temperatures revealed that the samples maintained their large-angle grain boundaries despite the increase in average grain size to around 536 and 720 nm for vacuum plasma spraying and suspension plasma spraying, respectively.

3.
Sci Rep ; 10(1): 10948, 2020 Jul 02.
Article in English | MEDLINE | ID: mdl-32616871

ABSTRACT

Rationally designed free-standing and binder-free Raney-type nickel-molybdenum (Ni-Mo) electrodes produced via atmospheric plasma spraying (APS) are developed by correlating APS process parameters with the microstructure of electrodes and their electrochemical performance in alkaline media. The results revealed that the electrode morphology and elemental composition are highly affected by the plasma parameters during the electrode fabrication. It is found that increasing plasma gas flow rate and input plasma power resulted in higher in-flight particle velocities and shorter dwell time, which in result delivered electrodes with much finer structure exhibiting homogeneous distribution of phases, larger quantity of micro pores and suitable content of Ni and Mo. Tafel slope of electrodes decreased with increasing the in-flight particles velocities from 71 to 33 mV dec-1 in 30 wt.% KOH. However, beyond a critical threshold in-flight velocity and temperature of particles, electrodes started to exhibit larger globular pores and consequently reduced catalytic performance and higher Tafel slop of 36 mV dec-1 in 30 wt.% KOH. Despite slightly lower electrochemical performance, the electrodes produced with highest plasma gas flow and energy showed most inter-particle bonded structure as well as highest stability with no measurable degradation over 47 days in operation as HER electrode in 30 wt.% KOH. The Raney-type Ni-Mo electrode fabricated at highest plasma gas flow rate and input plasma power has been tested as HER electrode in alkaline water electrolyzer, which delivered high current densities of 0.72 and 2 A cm-2 at 1.8 and 2.2 V, respectively, representing a novel prime example of HER electrode, which can synergistically catalyze the HER in alkaline electrolyzer. This study shows that sluggish alkaline HER can be circumvented by rational electrode composition and interface engineering.

4.
J Colloid Interface Sci ; 534: 47-54, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30205254

ABSTRACT

An innovative and simple synthesis strategy of silicon nanoparticle (Si NP) core covered by mesoporous shell carbon (MSC) structure is demonstrated. The Si core@MSC (SCMSC) composite is developed for addressing the issues for Si anode material in lithium ion batteries (LIBs) such as high volume expansion and low electrical conductivity. Significant improvement in the electrochemical performance for the SCMSC anode is observed compared with bare Si anode. The SCMSC composite delivers an initial specific capacity of 2450 mAh g-1 at 0.166 A g-1 with Coulombic efficiency of 99.2% for 100 cycles. Compared to bare Si anode, the SCMSC anode exhibits much higher Li storage capacity, superior cyclability, and good rate capability, highlighting the advantages of hierarchical MSC in the SCMSC structure.

5.
Sci Rep ; 7(1): 10910, 2017 09 07.
Article in English | MEDLINE | ID: mdl-28883659

ABSTRACT

Obtaining functionalized carbonaceous materials, with well-developed pores and doped heteroatoms, from waste precursors using environmentally friendly processes has always been of great interest. Herein, a simple template-free approach is devised to obtain porous and heteroatom-doped carbon, by using the most abundant human waste, "urine". Removal of inherent mineral salts from the urine carbon (URC) makes it to possess large quantity of pores. Synergetic effect of the heteroatom doping and surface properties of the URC is exploited by carrying out energy storage application for the first time. Suitable heteroatom content and porous structure can enhance the pseudo-capacitance and electric double layer capacitance, eventually generating superior capacitance from the URC. The optimal carbon electrode obtained particularly at 900 °C (URC-900) possesses high BET surface area (1040.5 m2g-1), good conductivity, and efficient heteroatom doping of N, S, and P, illustrating high specific capacitance of 166 Fg-1 at 0.5 Ag-1 for three-electrode system in inorganic electrolyte. Moreover, the URC-900 delivers outstanding cycling stability with only 1.7% capacitance decay over 5,000 cycles at 5 Ag-1. Present work suggests an economical approach based on easily available raw waste material, which can be utilized for large-scale production of new age multi-functional carbon nanomaterials for various energy applications.


Subject(s)
Carbon/chemistry , Electric Capacitance , Porosity , Urine/chemistry , Hot Temperature , Humans
6.
Sci Rep ; 6: 31555, 2016 08 17.
Article in English | MEDLINE | ID: mdl-27530441

ABSTRACT

In the race of gaining higher energy density, carbon's capacity to retain power density is generally lost due to defect incorporation and resistance increment in carbon electrode. Herein, a relationship between charge carrier density/charge movement and supercapacitance performance is established. For this purpose we have incorporated the most defect-free pristine graphene into defective/sacrificial graphene oxide. A unique co-solvent-based technique is applied to get a homogeneous suspension of single to bi-layer graphene and graphene oxide. This suspension is then transformed into a 3D composite structure of pristine graphene sheets (GSs) and defective N-doped reduced graphene oxide (N-RGO), which is the first stable and homogenous 3D composite between GS and RGO to the best of our knowledge. It is found that incorporation of pristine graphene can drastically decrease defect density and thus decrease relaxation time due to improved associations between electrons in GS and ions in electrolyte. Furthermore, N doping is implemented selectively only on RGO and such doping is shown to improve the charge carrier density of the composite, which eventually improves the energy density. After all, the novel 3D composite structure of N-RGO and GS greatly improves energy and power density even at high current density (20 A/g).

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