The detection of clinically relevant disease-specific biomolecules, including nucleic acids, circulating tumor cells, proteins, antibodies, and extracellular vesicles, has been indispensable to ...understand their functions in disease diagnosis and prognosis. Therefore, a biosensor for the robust, ultrasensitive, and selective detection of these low-abundant biomolecules in body fluids (blood, urine, and saliva) is emerging in current clinical research. In recent years, nanomaterials, especially superparamagnetic nanomaterials, have played essential roles in biosensing due to their intrinsic magnetic, electrochemical, and optical properties. However, engineered multicomponent magnetic nanoparticle-based current biosensors that offer the advantages of excellent stability in a complex biomatrix; easy and alterable biorecognition of ligands, antibodies, and receptor molecules; and unified point-of-care integration have yet to be achieved. This review introduces the recent advances in superparamagnetic nanostructures for electrochemical and optical biosensing for disease-specific biomarkers. This review emphasizes the synthesis, biofunctionalization, and intrinsic properties of nanomaterials essential for robust, ultrasensitive biosensing. With a particular emphasis on nanostructure-based electrochemical and optical detection of disease-specific biomarkers such as nucleic acids (DNA and RNA), proteins, autoantibodies, and cells, this review also chronicles the needs and challenges of nanoarchitecture-based detection. These summaries provide further insights for researchers to inspire their future work on the development of nanostructures for integrating into biosensing and devices for a broad field of applications in analytical sensing and in clinic.
Non-toxic metal halide perovskites have become forefront for commercialization of the perovskite solar cells and optoelectronic devices. In the present study, for the first time we show that ...particular metal doping in CsGeCl
3
halide can considerably enhance the absorbance both in the visible and ultraviolet light energy range. We have carried out DFT based first principles calculations on Mn-doped and Ni-doped CsGeCl
3
halide. We investigate the detailed structural, optical, electronic and mechanical properties of all the doped compositions theoretically. The study of the optical properties shows that the absorption edge of both Ni and Mn-doped CsGeCl
3
is shifted toward the low energy region (red shift) relative to the pristine one. An additional peak is observed for both doped profiles in the visible light energy region. The study of the mechanical properties demonstrates that both the doped samples are mechanically stable and ductile as the pristine CsGeCl
3
. The study of the electronic properties shows that the excitation of photoelectrons is easier due to the formation of intermediate states in Mn-doped CsGeCl
3
. As a result Mn-doped CsGeCl
3
exhibits higher absorptivity in the visible region than the Ni-doped counterpart. A combinational analysis indicates that CsGe
1−
x
Mn
x
Cl
3
is the best lead free candidate among the inorganic perovskite materials for solar cell and optoelectronic applications.
We have studied the optical, electronic and mechanical properties of Ni and Mn-doped CsGeCl
3
using DFT calculations.
Abstract
Inorganic non-toxic metal halide perovskites have taken the dominant place in commercialization of the optoelectronic devices. The first principles simulation has been executed with the help ...of density functional theory to investigate the structural, optical, electronic and mechanical properties of non-toxic CsSnCl
3
metal halide under various hydrostatic pressures up to 40 GPa. The analysis of optical functions displays that the absorption edge of CsSnCl
3
perovskite is shifted remarkably toward the low energy region (red shift) with enhanced pressure. The absorptivity, conductivity and the value of dielectric constant also increases with the applied pressure. The investigation of mechanical properties reveals CsSnCl
3
perovskite is mechanically stable as well as highly ductile and the ductility is increased with increasing pressure. The investigation of electronic properties shows semiconducting to metallic transition occurs in CsSnCl
3
under elevated pressure. The Physics behind all these changes under hydrostatic pressure has been analyzed and explained in details within the available Scientific theory.
Exosomes are nanoscale (≈30–150 nm) extracellular vesicles of endocytic origin that are shed by most types of cells and circulate in bodily fluids. Exosomes carry a specific composition of proteins, ...lipids, RNA, and DNA and can work as cargo to transfer this information to recipient cells. Recent studies on exosomes have shown that they play an important role in various biological processes, such as intercellular signaling, coagulation, inflammation, and cellular homeostasis. These functional roles are attributed to their ability to transfer RNA, proteins, enzymes, and lipids, thereby affecting the physiological and pathological conditions in various diseases, including cancer and neurodegenerative, infectious, and autoimmune diseases (e.g., cancer initiation, progression, and metastasis). Due to these unique characteristics, exosomes are considered promising biomarkers for the diagnosis and prognosis of various diseases via noninvasive or minimally invasive procedures. Over the last decade, a plethora of methodologies have been developed for analyzing disease‐specific exosomes using optical and nonoptical tools. Here, the major biological functions, significance, and potential role of exosomes as biomarkers and therapeutics are discussed. Furthermore, an overview of the most commonly used techniques for exosome analysis, highlighting the major technical challenges and limitations of existing techniques, is presented.
Exosomes are promising biomarkers in the diagnosis, prognosis, and therapeutics of many human diseases including cancer. The biogenesis and biological significance of exosomes are summarized. Recent advances in strategies for isolation and detection of exosomes, and their potential for clinical diagnostics are discussed. An overview of the key technical and biological challenges, potential solutions, and future perspectives are provided.
Non-toxic (lead-free) inorganic perovskites have seized the leading position in the race for the commercialization of solar cells and other photovoltaic devices. The present study is the first ...theoretical approach to show that metal (Cr/Mn)-doped CsSnCl3 perovskites exhibit high optical absorption, high photoconductivity, and high dielectric constant not only in the visible but also in the ultraviolet region of light energy due to the narrowing band gap. We carried out density functional theory (DFT) investigations to find the structural, electronic, optical, and mechanical properties of pristine CsSnCl3, Cr-, and Mn-doped CsSnCl3 samples in detail. The investigation of the optical functions displayed that the absorption edges of both Cr- and Mn-doped CsSnCl3 shifted greatly in the direction of the low photon energy area (red-shift) compared with the pristine sample. An extra very high intensity peak of absorption was noted for both Cr- and Mn-doped CsSnCl3 in the visible energy region. The investigation of the mechanical parameters revealed that both Cr- and Mn-doped CsSnCl3 samples were as mechanically stable and highly ductile as the pure CsSnCl3 sample. The investigation of the electronic properties demonstrated that the creation of intermediate states in the band gap for both the Cr- and Mn-doped CsSnCl3 samples made the transition of excited photoelectrons to the conduction band from the valence band easier. A combined study suggested that Mn-doped CsSnCl3 was better suited for applications in high potency solar cells and other optoelectronic devices than the other inorganic metal halide perovskites.
Malaria is a blood disease caused by the
parasites transmitted through the bite of female Anopheles mosquito. Microscopists commonly examine thick and thin blood smears to diagnose disease and ...compute parasitemia. However, their accuracy depends on smear quality and expertise in classifying and counting parasitized and uninfected cells. Such an examination could be arduous for large-scale diagnoses resulting in poor quality. State-of-the-art image-analysis based computer-aided diagnosis (CADx) methods using machine learning (ML) techniques, applied to microscopic images of the smears using hand-engineered features demand expertise in analyzing morphological, textural, and positional variations of the region of interest (ROI). In contrast, Convolutional Neural Networks (CNN), a class of deep learning (DL) models promise highly scalable and superior results with end-to-end feature extraction and classification. Automated malaria screening using DL techniques could, therefore, serve as an effective diagnostic aid. In this study, we evaluate the performance of pre-trained CNN based DL models as feature extractors toward classifying parasitized and uninfected cells to aid in improved disease screening. We experimentally determine the optimal model layers for feature extraction from the underlying data. Statistical validation of the results demonstrates the use of pre-trained CNNs as a promising tool for feature extraction for this purpose.
Liquids and gases produced through biomass pyrolysis have potential as renewable fuels to replace fossil fuels in conventional internal combustion engines. This review compares the properties of ...pyrolysis fuels, produced from a variety of feedstocks and using different pyrolysis techniques, against those of fossil fuels. High acidity, the presence of solid particles, high water content, high viscosity, storage and thermal instability, and low energy content are typical characteristics of pyrolysis liquids. A survey of combustion, performance and exhaust emission results from the use of pyrolysis liquids (both crude and up-graded) in compression ignition engines is presented. With only a few exceptions, most authors have reported difficulties associated with the adverse properties of pyrolysis liquids, including: corrosion and clogging of the injectors, long ignition delay and short combustion duration, difficulty in engine start-up, unstable operation, coking of the piston and cylinders and subsequent engine seizure. Pyrolysis gas can be used more readily, either in spark ignition or compression ignition engines; however, NOx reduction techniques are desirable. Various approaches to improve the properties of pyrolysis liquids are discussed and a comparison of the properties of up-graded vs. crude pyrolysis liquid is included. Further developments in up-gradation techniques, such as hydrocracking and bio-refinery approaches, could lead to the production of green diesel and green gasoline. Modifications required to engines for use with pyrolysis liquids, for example in the fuel supply and injection systems, are discussed. Storage stability and economic issues are also reviewed. Our study presents recent progress and important R&D areas for successful future use of pyrolysis fuels in internal combustion engines.
Shigellaa Gram-negative, non-motile bacillus, is the primary causative agent of the infectious disease shigellosis, which kills 1.1 million people worldwideevery year. The children under the age of ...five are primarily the victims of this disease. This study has been conducted to assess the prevalence of shigellosis through selective plating, biochemical test and conventional PCR assays, where the samples were collected from suspected diarrheoal patients. Invasive plasmid antigen H (ipaH) and O-antigenic rfc gene were used to identify Shigella spp. and S. flexneri respectively. For validation of these identification, PCR product of ipaH gene of a sample (Shigella flexneri MZS 191) has been sequenced and submitted to NCBI database (GenBank accession no- MW774908.1). Further this strain has been used as positive control. Out of 204, around 14.2% (n = 29)(P> 0.01) pediatric diarrheoal cases were screened as shigellosis. Another interesting finding was that most of shigellosis affected children were 7 months to 1 year (P> 0.01).The significance of this study lies in the analyses of the occurrenceand the molecular identification of Shigellaspp. and S. flexneri that can be utilized in improving the accurate identification and the treatment of the most severe and alarming shigellosis.
This research article reports on factors influencing initial voluntary uptake of community-based health insurance (CBHI) schemes in low- and middle-income countries (LMIC), and renewal decisions.
...Following PRISMA protocol, we conducted a comprehensive search of academic and gray literature, including academic databases in social science, economics and medical sciences (e.g., Econlit, Global health, Medline, Proquest) and other electronic resources (e.g., Eldis and Google scholar). Search strategies were developed using the thesaurus or index terms (e.g., MeSH) specific to the databases, combined with free text terms related to CBHI or health insurance. Searches were conducted from May 2013 to November 2013 in English, French, German, and Spanish. From the initial search yield of 15,770 hits, 54 relevant studies were retained for analysis of factors influencing enrolment and renewal decisions. The quantitative synthesis (informed by meta-analysis) and the qualitative analysis (informed by thematic synthesis) were compared to gain insight for an overall synthesis of findings/statements.
Meta-analysis suggests that enrolments in CBHI were positively associated with household income, education and age of the household head (HHH), household size, female-headed household, married HHH and chronic illness episodes in the household. The thematic synthesis suggests the following factors as enablers for enrolment: (a) knowledge and understanding of insurance and CBHI, (b) quality of healthcare, (c) trust in scheme management. Factors found to be barriers to enrolment include: (a) inappropriate benefits package, (b) cultural beliefs, (c) affordability, (d) distance to healthcare facility, (e) lack of adequate legal and policy frameworks to support CBHI, and (f) stringent rules of some CBHI schemes. HHH education, household size and trust in the scheme management were positively associated with member renewal decisions. Other motivators were: (a) knowledge and understanding of insurance and CBHI, (b) healthcare quality, (c) trust in scheme management, and (d) receipt of an insurance payout the previous year. The barriers to renewal decisions were: (a) stringent rules of some CBHI schemes, (b) inadequate legal and policy frameworks to support CBHI and (c) inappropriate benefits package.
The demand-side factors positively affecting enrolment in CBHI include education, age, female household heads, and the socioeconomic status of households. Moreover, when individuals understand how their CBHI functions they are more likely to enroll and when people have a positive claims experience, they are more likely to renew. A higher prevalence of chronic conditions or the perception that healthcare is of good quality and nearby act as factors enhancing enrolment. The perception that services are distant or deficient leads to lower enrolments. The second insight is that trust in the scheme enables enrolment. Thirdly, clarity about the legal or policy framework acts as a factor influencing enrolments. This is significant, as it points to hitherto unpublished evidence that governments can effectively broaden their outreach to grassroots groups that are excluded from social protection by formulating supportive regulatory and policy provisions even if they cannot fund such schemes in full, by leveraging people's willingness to exercise voluntary and contributory enrolment in a community-based health insurance.
PDF
