Corrosion is a subject of interest to interdisciplinary research communities, combining fields of materials science, chemistry, physics, metallurgy and chemical engineering. In order to understand ...mechanisms of corrosion and the function of corrosion inhibitors, the reactions at the interfaces between the corrosive electrolyte and a steel surface, particularly at the initial stages of the corrosion process, need to be described. Naturally, these reactions are strongly affected by the nature and properties of the steel surfaces. It is however seen that the majority of recent corrosion and corrosion-inhibition investigations are limited to electrochemical testing, with
ex situ
analysis of the treated steels (post-exposure analysis). The characterization of materials and their surface properties, such as texture and morphology, are not being considered in most studies. Similarly,
in situ
investigations of the initial stages of the corrosion reactions using advanced surface characterization techniques are scarce. In this review, attention is brought to the importance of surface features of carbon steels, such as texture and surface energy, along with defects dislocation related to mechanical processing of carbon steels. This work is extended to a critical review of surface analytical techniques used for characterization of carbon steels in corrosive media with particular focus on examining steel surfaces treated with corrosion inhibitors. Further, emerging surface analysis techniques and their applicability to analyse carbon steels in corrosive media are discussed. The importance of surface properties is commonly addressed by surface scientists as well as researchers in other chemistry fields such as nanotechnology, fuel cells, and catalysis. This article is expected to appeal to a broad scientific community, including but not limited to corrosion scientists, material chemists, analytical chemists, metal physicists, corrosion and materials engineers.
The effects of surface morphology, defects, texture and energy on carbon steel corrosion are elucidated along with relevant characterization methods.
Objective: To investigate wound healing, antimicrobial and antioxidant activity of leaf extract of Pongamia Pinnata. Materials and methods: Methanolic extracts of P. pinnata leaf were studied for ...wound healing efficiency, and was assessed by the rate of wound contraction, tensile strength, breaking strength, hydroxyproline and hexosamine content, along with its effect on pro-inflammatory and anti-inflammatory cytokines was assessed using excision and incision model of wound repair in Wistar rats. Antimicrobial activity against ten microorganisms was also assessed. In vivo antioxidant activity was performed to understand the mechanism of wound healing potency. Results: The results indicated that P. pinnata extract has potent wound healing capacity as evident from the wound contraction and increased tensile strength. Hydroxyproline and hexosamine expression were also well correlated with the healing pattern observed. extract exhibited significant antimicrobial activity, Staphylococcus aureus, Staphylococcus pyogenes, Staphylococcus epidermidis, Escherichia coli, Micrococcus luteus, Enterobacter aerogenes, Salmonella typhi, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger also indicate that P. pinnata posses potent antioxidant activity by inhibition lipid per-oxidation, reduce glutathione, superoxide dismutase level and increases catalase activity. During early wound healing phase TNF-α and IL-6 level were found to be up-regulated by P. pinnata treatment. Conclusion: Increased wound contraction and tensile strength, augmented hydroxyproline and hexosamine content, antioxidative activity and moderate antimicrobial activity support the early wound healing exhibited by P. pinnata. Induction in cytokine production may be one of the mechanisms in accelerating the wound healing. Results suggest that P. pinnata may be useful in tropical management of wound healing.
The purpose is to study the anatomical outcome of eyes in aggressive retinopathy of prematurity (AROP), treated with laser photocoagulation alone and to evaluate factors affecting outcomes.
Records ...of consecutive babies diagnosed with AROP, undergoing laser photocoagulation treatment in rural tertiary care centers from October 2016 to January 2021 were reviewed retrospectively. Anatomical outcome at 6 months follow-up was grouped as good in eyes with complete regression and poor in those who developed retinal detachment (stage IV a, IV b, and V). Both groups were compared with respect to the period of gestation, birth weight (BW), age at screening, age at treatment, zone of disease, presence of retinal fibrovascular proliferation (FVP), tunica vasculosa lentis, preretinal bleed, need for supplement laser, and associated systemic risk factors.
Of the total of 2468 babies screened, 124 (5.02%) were diagnosed with severe retinopathy of prematurity (ROP), of which 54 (43.5%) lasered AROP babies were analyzed. Mean BW and gestation period of the AROP cohort were 1.43 kg and 31.1 weeks, respectively. Eighty-six eyes (79.6%) had good outcomes with laser photocoagulation alone. Posterior location of disease, presence of FVP, neonatal sepsis, shock, and late screening for ROP were found to be factors associated with poor outcomes.
Adequate and timely treatment with laser photocoagulation in AROP can achieve good treatment outcomes in a significant proportion of babies. Although a combined approach using laser, anti-vascular endothelial growth factor and early vitrectomy is better, laser remains a viable treatment option in AROP, especially with limited resources and high risk of loss to follow-up.
Purpose: To describe the prevalence, characteristics including risk factors, and pattern of severe ROP from eastern Madhya Pradesh region of India. Methods: In this 5-year retrospective study, ...Baseline characteristics, systemic risk factors, and findings of ROP screening were noted. Factors associated with severe ROP including aggressive posterior ROP (APROP), stage IV and V ROP were analyzed. Statistical analysis was done using SPSS version 20. Results: Of 763 babies screened, 30% were diagnosed to have ROP. Prevalence of severe ROP was 14.2% (109) of which 60 (55.5%) were classic and 30 (27.7%) were APROP. Eighteen (16.6%) were diagnosed as advanced ROP (stage IV and V). Mean gestational age (GA) and birth weight (BW) for severe ROP were 31.05 weeks and 1.34 kg, respectively which were inversely associated with severe ROP. But a significant 10% of severe ROP were seen in late preterm babies, >34 weeks. Low GA and respiratory distress syndrome (RDS) were significant risk factors for APROP. Most important factor for stage IV and V ROP was late presentation for screening. Conclusion: The study found a high prevalence of severe ROP including APROP. Almost 7% severe ROP cases were outside screening guidelines of NNF. Late presentation for screening is the most important factor associated with ROP related blindness.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Kafirin, the hydrophobic prolamin storage protein in sorghum grain is enriched when the grain is used for bioethanol production to give dried distillers grain with solubles (DGGS) as a ...by-product. There is great interest in DDGS kafirin as a new source for biomaterials. There is however a lack of fundamental understanding of how the physicochemical properties of DDGS kafirin having been exposed to the high temperature conditions during ethanol production, compare to kafirin made directly from the grain. An understanding of these properties is required to catalyse the utilisation of DDGS kafirin for biomaterial applications. The aim of this study was to extract kafirin directly from sorghum grain and from DDGS derived from the same grain and, then perform a comparative investigation of the physicochemical properties of these kafirins in terms of: polypeptide profile by sodium-dodecyl sulphate polyacrylamide gel electrophoresis; secondary structure by Fourier transform infra-red spectroscopy and x-ray diffraction, self-assembly behaviour by small-angle x-ray scattering, surface morphology by scanning electron microscopy and surface chemical properties by energy dispersive x-ray spectroscopy. DDGS kafirin was found to have very similar polypeptide profile as grain kafirin but contained altered secondary structure with increased levels of β-sheets. The structure morphology showed surface fractals and surface elemental composition suggesting enhanced reactivity with possibility to endow interfacial wettability. These properties of DDGS kafirin may provide it with unique functionality and thus open up opportunities for it to be used as a novel food grade biomaterial.
Ancient Indian iron artefacts have always fascinated researchers due to their excellent corrosion resistance, but the scientific explanation of this feature remains to be elucidated. We have ...investigated corrosion resistance of iron manufactured according to traditional metallurgical processes by the Indian tribes called 'Agaria'. Iron samples were recovered from central India (Aamadandh, Korba district, Chhattisgarh). Iron artefacts are investigated using a range of correlative microscopic, spectroscopic, diffraction and tomographic techniques to postulate the hidden mechanisms of superlative corrosion resistance. The importance of manufacturing steps, ingredients involved in Agaria's iron making process, and post-metal treatment using metal-working operation called hot hammering (forging) is highlighted. This study also hypothesizes the probable protective mechanisms of corrosion resistance of iron. Findings are expected to have a broad impact across multiple disciplines such as archaeology, metallurgy and materials science.
Urothelial carcinoma has become the ninth most common malignancy in the world. Since the 1980s, diverse studies and treatment methods came out with their possible effects along with certain ...limitations. Initially, platinum chemotherapy was considered as first-line treatment of the disease. Although it was proved to be effective initially, the most number of cases reported the reoccurrence of the disease. Furthermore, aberrant ligand- dependent and constitutive ligand-independent fibroblast growth factor receptor (FGFR) signaling has been reported in a large number of solid tumors, including urothelial carcinoma that became the basis for FGFR inhibition for the treatment of the disease. Erdafitinib is a pan-FGFR inhibitor that was recently approved in the USA for the treatment of locally advanced or metastatic FGFR3 or FGFR2 urothelial carcinoma. The drug is also being investigated as a treatment for other cancers, including cholangiocarcinoma, liver cancer, non-small cell lung cancer, prostate cancer, lymphoma cancer and oesophageal cancer. This article summarizes the various treatments that evolved for bladder cancer till now, a brief description of the biology of FGFR inhibition, clinical pharmacology, and various clinical trials of erdafitinib.
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