scholarly journals Microbial Bioremediation of Feather Waste for Keratinase Production: An Outstanding Solution for Leather Dehairing in Tanneries

2020 ◽  
Vol 13 ◽  
pp. 117863612091328 ◽  
Author(s):  
Mursheda Akhter ◽  
Lolo Wal Marzan ◽  
Yasmin Akter ◽  
Kazuyuki Shimizu
Keyword(s):  
Enzyme Purification ◽  
Large Scale ◽  
Batch Cultivation ◽  
Potential Candidate ◽  
Pseudomonas Sp ◽  
Feather Waste ◽  
Alternative Approach ◽  
Keratinase Enzyme ◽  
Alternative Processes ◽  
Microbial Bioremediation

In leather industries and tanneries, large amount of wastes has been disposed; which polluting water, soil, and atmosphere and causing serious human health problems. In particular, chemical dehairing process of leather industries produces fair amount of toxic wastes. It is, thus, urgently needed to use alternative processes free from pollution. As more than 90% of keratin is contained in feather, it is desirable to develop bioremediation process using keratinolytic microorganisms. In the present investigation, therefore, we first identified Bacillus cereus and Pseudomonas sp. to be able to produce keratinase. Then, the optimization was performed to maximize the keratinase activity with respect to cultivation temperature, pH, and incubation time. Moreover, the effects of metal ions and various substrates on keratinase activity were also investigated. The result indicates that keratinase activity became maximum at 50°C for both strains, whereas the optimal pH was 10.0 for B. cereus and 7.0 for Pseudomonas sp. The highest keratinase activity of 74.66 ± 1.52 U/mL was attained by B. cereus, whereas 57.66 ± 2.52 U/mL was attained by Pseudomonas sp. Enzymatic dehairing efficiency of leathers was also compared with chemical dehairing (Na2S and CaO), where complete dehairing was achieved by treating them with crude keratinase. Partial enzyme purification was performed by acetone precipitation. Batch cultivation of B. cereus using 1 L fermentor indicates a potential candidate for large-scale keratinase production. Thus, keratinase enzyme by degrading poultry wastes (feather) can be an alternative approach to chemical dehairing in leather industries, thus preventing environmental pollution through bioremediation.

scholarly journals Carbon Nanotubes and Polydopamine Modified Poly(dimethylsiloxane) Sponges for Efficient Oil–Water Separation

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2431
Author(s):  
Wen Zhang ◽  
Juanjuan Wang ◽  
Xue Han ◽  
Lele Li ◽  
Enping Liu ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Large Scale ◽  
Absorption Capacity ◽  
Potential Candidate ◽  
Hard Template ◽  
Water Separation ◽  
Industrial Oil ◽  
The Matrix ◽  
Oil Water Separation ◽  
Oil Water

In this paper, effective separation of oil from both immiscible oil–water mixtures and oil-in-water (O/W) emulsions are achieved by using poly(dimethylsiloxane)-based (PDMS-based) composite sponges. A modified hard template method using citric acid monohydrate as the hard template and dissolving it in ethanol is proposed to prepare PDMS sponge composited with carbon nanotubes (CNTs) both in the matrix and the surface. The introduction of CNTs endows the composite sponge with enhanced comprehensive properties including hydrophobicity, absorption capacity, and mechanical strength than the pure PDMS. We demonstrate the successful application of CNT-PDMS composite in efficient removal of oil from immiscible oil–water mixtures within not only a bath absorption, but also continuous separation for both static and turbulent flow conditions. This notable characteristic of the CNT-PDMS sponge enables it as a potential candidate for large-scale industrial oil–water separation. Furthermore, a polydopamine (PDA) modified CNT-PDMS is developed here, which firstly realizes the separation of O/W emulsion without continuous squeezing of the sponge. The combined superhydrophilic and superoleophilic property of PDA/CNT-PDMS is assumed to be critical in the spontaneously demulsification process.

scholarly journals Recovery of FTO coated glass substrate via environment-friendly facile recycling perovskite solar cells

RSC Advances ◽  
2021 ◽  
Vol 11 (24) ◽  
pp. 14534-14541
Author(s):  
M. S. Chowdhury ◽  
Kazi Sajedur Rahman ◽  
Vidhya Selvanathan ◽  
A. K. Mahmud Hasan ◽  
M. S. Jamal ◽  
...  
Keyword(s):  
Solar Cells ◽  
Glass Substrate ◽  
Large Scale ◽  
Low Cost ◽  
Perovskite Solar Cells ◽  
Potential Candidate ◽  
Photovoltaic Devices ◽  
Coated Glass Substrate ◽  
Environment Friendly ◽  
Coated Glass

Organic–inorganic perovskite solar cells (PSCs) have recently emerged as a potential candidate for large-scale and low-cost photovoltaic devices.

scholarly journals Zebrafish Cancer Predisposition Models

2021 ◽  
Vol 9 ◽  
Author(s):  
Kim Kobar ◽  
Keon Collett ◽  
Sergey V. Prykhozhij ◽  
Jason N. Berman
Keyword(s):  
Large Scale ◽  
Genetic Manipulation ◽  
Bone Marrow Failure ◽  
Cancer Predisposition ◽  
Potential Candidate ◽  
Cancer Evolution ◽  
High Fecundity ◽  
Cancer Models ◽  
The Impact

Cancer predisposition syndromes are rare, typically monogenic disorders that result from germline mutations that increase the likelihood of developing cancer. Although these disorders are individually rare, resulting cancers collectively represent 5–10% of all malignancies. In addition to a greater incidence of cancer, affected individuals have an earlier tumor onset and are frequently subjected to long-term multi-modal cancer screening protocols for earlier detection and initiation of treatment. In vivo models are needed to better understand tumor-driving mechanisms, tailor patient screening approaches and develop targeted therapies to improve patient care and disease prognosis. The zebrafish (Danio rerio) has emerged as a robust model for cancer research due to its high fecundity, time- and cost-efficient genetic manipulation and real-time high-resolution imaging. Tumors developing in zebrafish cancer models are histologically and molecularly similar to their human counterparts, confirming the validity of these models. The zebrafish platform supports both large-scale random mutagenesis screens to identify potential candidate/modifier genes and recently optimized genome editing strategies. These techniques have greatly increased our ability to investigate the impact of certain mutations and how these lesions impact tumorigenesis and disease phenotype. These unique characteristics position the zebrafish as a powerful in vivo tool to model cancer predisposition syndromes and as such, several have already been created, including those recapitulating Li-Fraumeni syndrome, familial adenomatous polyposis, RASopathies, inherited bone marrow failure syndromes, and several other pathogenic mutations in cancer predisposition genes. In addition, the zebrafish platform supports medium- to high-throughput preclinical drug screening to identify compounds that may represent novel treatment paradigms or even prevent cancer evolution. This review will highlight and synthesize the findings from zebrafish cancer predisposition models created to date. We will discuss emerging trends in how these zebrafish cancer models can improve our understanding of the genetic mechanisms driving cancer predisposition and their potential to discover therapeutic and/or preventative compounds that change the natural history of disease for these vulnerable children, youth and adults.

scholarly journals Novel Keratinolytic Activity of Cyberlindnera fabianii Nrc3 Aza as A Plant Growth Promoting Agent (PGPA)

2015 ◽  
Vol 3 (4) ◽  
pp. 609-618 ◽  
Author(s):  
Azza M. Abdel-fattah ◽  
EL-Shahat H. A. Nashy ◽  
El-Tahir A. Sabiel ◽  
Manal M. Hussien ◽  
Ahmed S. Attia
Keyword(s):  
Plant Growth ◽  
Field Experiments ◽  
The Novel ◽  
Keratinolytic Activity ◽  
Morphological Studies ◽  
Feather Waste ◽  
Plant Growth Promoting ◽  
Growth Promoting ◽  
Keratinase Enzyme

Two field experiments had been conducted in Nubaria sandy soil, Behaira Governate, Egypt to show the effect of keratinase enzyme produced by the novel microbial isolate (Cyberlindnera fabianii NRC3 Aza) on plants.The trials had been conducted in the two successive summer seasons (2011/2012 and 2012/2013) to show the effect of keratinase enzyme from degraded feather–waste on the morphology and chemical composition of peas pods (Pisumsativum L.)–family Fabaceae (Leguminasae). In 2011/2012 season, only the chemical analysis of the dried powdered beads was studied. In 2012/2013 season, the morphological studies of the yield were considered beside the chemical ones. The results depicted significant effects of the sprayed enzyme (keratinase) on peas as plant growth promoting agent (PGPA), compared with the blank (sprayed with water). Electrophoreses and amino acid analysis were carried out for the characterization of the partial pure keratinase enzyme. Int J Appl Sci Biotechnol, Vol 3(4): 609-618

scholarly journals 1240. Evaluation of Preoperative Staphylococcus aureus (SA) Decolonization with Nasal Iodine for Hips/Knees and Fusion Surgeries

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S446-S447
Author(s):  
Anupama Neelakanta ◽  
Kristi Clutts ◽  
Stephanie Strollo ◽  
Catherine Passaretti
Keyword(s):  
Staphylococcus Aureus ◽  
Large Scale ◽  
Nasal Carriage ◽  
Pcr Screening ◽  
Total Knee Replacements ◽  
Alternative Approach ◽  
Hip Replacements ◽  
Intranasal Mupirocin ◽  
History Of ◽  
Total Knee

Abstract Background Preoperative decolonization for patients with known nasal carriage of Staphylococcus aureus is recommended in some surgical site infection (SSI) guidelines, however, meaningful implementation is often challenging with poor compliance. We evaluated utilization of nasal iodine with S. aureus polymerase chain reaction (PCR) screening on the day of surgery as an alternative approach. Methods For all total hip replacements (THR), total knee replacements (TKR) and fusion patients in a 250-bed community hospital, we implemented day of surgery S. aureus PCR for all patients who had not been screened in the 2 weeks prior in August 2018. Those known to have S. aureus colonization in the 2 weeks prior to surgery as well as those who had no screen in the 2 weeks prior were treated with nasal iodine and received a chlorhexidine (CHG) bath in the preoperative area. Postoperatively any patient found to have (methicillin-resistant S. aureus) MRSA from preoperative screen or who had a history of MRSA in the past year were automatically decolonized with 5 days of intranasal mupirocin and CHG baths in addition. Compliance with S. aureus screening in preoperative area, results of screens and rates of THR, TKR and fusion SSI per National Health Safety Network (NHSN) definitions were monitored throughout the study period. SSI standardized infection ratios (SIR) during the study were compared with data 1 year prior to intervention date. Results Between August 2018 and January 2019, 694 THR, TKR and fusion surgeries were performed. Preoperative nursing compliance with completing the SA screen was 79. 2% and percent compliance with administering/documenting nasal iodine was 77.8%. Of those screened 21.7% (126/578) were found to have SA. Only 15% (n = 19) of SA positive PCRs were positive for MRSA. SSIs decreased in intervention period compared with preintervention (August 2017–July 2018) as shown in Table 1. Conclusion Preoperative nasal iodine has been effective and helped reduce our infection SIR to below 1. These results could be confounded by the presence of other initiatives but looks promising and large-scale studies would be helpful to make these results generalizable. Disclosures All authors: No reported disclosures.

scholarly journals Continuous, Strong, Porous Silk Firoin-Based Aerogel Fibers toward Textile Thermal Insulation

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1899 ◽  
Author(s):  
Haiwei Yang ◽  
Zongqian Wang ◽  
Zhi Liu ◽  
Huan Cheng ◽  
Changlong Li
Keyword(s):  
Heat Transfer ◽  
Thermal Insulation ◽  
Hollow Fiber ◽  
High Performance ◽  
Large Scale ◽  
Low Density ◽  
Potential Candidate ◽  
Scale Production ◽  
Insulation Material ◽  
High Porosity

Aerogel fiber, with the characteristics of ultra-low density, ultra-high porosity, and high specific surface area, is the most potential candidate for manufacturing wearable thermal insulation material. However, aerogel fibers generally show weak mechanical properties and complex preparation processes. Herein, through firstly preparing a cellulose acetate/polyacrylic acid (CA/PAA) hollow fiber using coaxial wet-spinning followed by injecting the silk fibroin (SF) solution into the hollow fiber, the CA/PAA-wrapped SF aerogel fibers toward textile thermal insulation were successfully constructed after freeze-drying. The sheath (CA/PAA hollow fiber) possesses a multiscale porous structure, including micropores (11.37 ± 4.01 μm), sub-micron pores (217.47 ± 46.16 nm), as well as nanopores on the inner (44.00 ± 21.65 nm) and outer (36.43 ± 17.55 nm) surfaces, which is crucial to the formation of a SF aerogel core. Furthermore, the porous CA/PAA-wrapped SF aerogel fibers have many advantages, such as low density (0.21 g/cm3), high porosity (86%), high strength at break (2.6 ± 0.4 MPa), as well as potential continuous and large-scale production. The delicate structure of multiscale porous sheath and ultra-low-density SF aerogel core synergistically inhibit air circulation and limit convective heat transfer. Meanwhile, the high porosity of aerogel fibers weakens heat transfer and the SF aerogel cellular walls prevent infrared radiation. The results show that the mat composed of these aerogel fibers exhibits excellent thermal insulating properties with a wide working temperature from −20 to 100 °C. Therefore, this SF-based aerogel fiber can be considered as a practical option for high performance thermal insulation.

scholarly journals Internal tide energy flux over a ridge measured by a co-located ocean glider and moored ADCP

2019 ◽  
Author(s):  
Rob Hall ◽  
Barbara Berx ◽  
Gillian Damerell
Keyword(s):  
Energy Flux ◽  
Large Scale ◽  
Low Frequency ◽  
Internal Tide ◽  
Small Scale ◽  
Potential Density ◽  
The North ◽  
Model Study ◽  
Continental Shelves ◽  
Alternative Approach

Abstract. Internal tide energy flux is an important diagnostic for the study of energy pathways in the ocean, from large-scale input by the surface tide, to small-scale dissipation by turbulent mixing. Accurate calculation of energy flux requires repeated full-depth measurements of both potential density (ρ) and horizontal current velocity (u) over at least a tidal cycle and over several weeks to resolve the internal spring-neap cycle. Typically, these observations are made using full-depth oceanographic moorings that are vulnerable to being fished-out by commercial trawlers when deployed on continental shelves and slopes. Here we test an alternative approach to minimise these risks, with u measured by a low-frequency ADCP moored near the seabed and ρ measured by an autonomous ocean glider holding station by the ADCP. The method is used to measure the M2 internal tide radiating from the Wyville Thompson Ridge in the North Atlantic. The observed energy flux (4.2 ± 0.2 kW m−1) compares favourably with historic observations and a previous numerical model study. Error in the energy flux calculation due to imperfect co-location of the glider and ADCP is estimated by sub-sampling potential density in an idealised internal tide field along pseudorandomly distributed glider paths. The error is considered acceptable (

scholarly journals Homothetic Behavior of Betweenness Centralities: A Multiscale Alternative Approach to Relate Cities and Large Regional Structures

2020 ◽  
Vol 12 (19) ◽  
pp. 7925
Author(s):  
Diego Altafini ◽  
Valerio Cutini
Keyword(s):  
Large Scale ◽  
Computing Methods ◽  
Regional Network ◽  
Large Scale Structures ◽  
Processing Power ◽  
Alternative Approach ◽  
Urban Settlements ◽  
Sheer Size ◽  
Scale Structures ◽  
Network Centralities

Regional configuration can reveal important aspects about city sustainability, as local-regional interactions shape the evolution and inner geography of urban settlements. However, modelling these large-scale structures remains a challenge, due to their sheer size as physical objects. Despite recent improvements in processing power and computing methods, extensive time periods are still required for ordinary microprocessors to model network centralities in road-graphs with high element counts, connectivity and topological depth. Generalization is often the chosen option to mitigate time-constraints of regional network complexity. Nevertheless, this can impact visual representation and model precision, especially when multiscale comparisons are desired. Tests using Normalized Angular Choice (NACH), a Space Syntax mathematical derivative of Betweenness Centrality, found recursive visual similitudes in centrality spatial distribution when modelling distinct scaled map sections of the same large regional network structure. Therefore, a sort of homothetic behavior is identified, since statistical analyses demonstrate that centrality values and distributions remain rather consistent throughout scales, even when considering edge effects. This paper summarizes these results and considers homotheties as an alternative to extensive network generalization. Hence, data maps can be constructed sooner and more accurately as “pieces of a puzzle”, since each individual lesser scale graph possesses a faster processing time.

scholarly journals Screening of Keratinolytic Bacteria from Poultry Wastes

1970 ◽  
Vol 45 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Z Jahan ◽  
SN Khan ◽  
M Mozammel Hoque
Keyword(s):  
Large Scale ◽  
Biochemical Analysis ◽  
Specific Activity ◽  
Basal Medium ◽  
Bacillus Sp ◽  
Carbon And Nitrogen ◽  
Feather Waste ◽  
Key Words Identification ◽  
Bacillus Spp ◽  
Poultry Feather

The aim of this study was to characterize keratinolytic bacteria isolated from feather waste. Six isolates were recovered from poultry feather- decomposed materials. Isolate Z3 and Z4 showed important feather degrading activity when grown on basal medium containing 1% native feather as the only source of energy, carbon and nitrogen. All isolates were Gram positive and rod-shaped bacilli. Based on microscopic and biochemical analysis, the isolates were identified as Bacillus spp. Keratinolytic activities of these isolates were measured after cultivation of the bacteria on raw feathers. Maximum keratinase activity was showed by the isolate Z4 (22.3 U/ml) with the specific activity of 40.5 U/mg. Bacillus sp. Z4 is a potent producer of keratinase, which can be used for production of the enzyme in large scale. Key words: Identification; Purification; Characterization; Keratinase; Feather DOI: 10.3329/bjsir.v45i3.6535Bangladesh J. Sci. Ind. Res. 45(3), 261-266, 2010

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