Informal settlement segmentation using VHR RGB and height information from UAV imagery: a case study of Nepal

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial TechnologiesInformal settlement in developing countries are complex. They are contextually and radiometrically very similar to formal settlement. Resolution offered by Remote sensing is not sufficient to capture high variations and feature size in informal settlements in these situations. UAV imageries offers solution with higher resolution. Incorporating UAV image and normalized DSM obtained from UAV provides an opportunity of including information on 3D space. This can be a crucial factor for informal settlement extraction in countries like Nepal. While formal and informal settlements have similar texture, they differ significantly in height. In this regard, we propose segmentation of informal settlement of Nepal using UAV and normalized DSM, against traditional approach of orthophoto only or orthophoto and DSM. Absolute height, normalized DSM(nDSM) and vegetation index from visual band added to 8 bit RGB channels are used to locate informal settlements. Segmentation including nDSM resulted in 6 % increment in Intersection over Union for informal settlements. IoU of 85% for informal settlement is obtained using nDSM trained end to end on Resnet18 based Unet. Use of threshold value had same effect as using absolute height, meaning use of threshold does not alter result from using absolute nDSM. Integration of height as additional band showed better performance over model that trained height separately. Interestingly, benefits of vegetation index is limited to settlements with small huts partly covered with vegetation, which has no or negative effect elsewhere

Dental caries, tobacco usage and associated risk factor of dental caries in patients visiting a government hospital in Western, Nepal

Abstract Background This study was conducted to assess the prevalence of dental caries, tobacco usage, and associated risk factors for dental caries in patients who visited a government hospital in Western, Nepal. Methods This analytical cross-sectional study was conducted from January to April 2022. Patients above 18 years visiting the dental OPD of a government hospital, and who had provided informed consent were enrolled in the study using a convenience sampling technique. As the study also involved an illiterate population, in that case, informed consent was obtained from their respective legal guardian as well. A pretested standardized, close-ended questionnaire was administered by researchers to gather information regarding the associated risk factors and oral hygiene practices. Clinical examination was done for dental caries according to the criteria by the World Health Organization (WHO) using the “DMFT” index (WHO modification 1987). Bivariate and multivariable logistic regression was done and the odds ratio and p-value was calculated. For all tests, statistical significance was set at p < 0.05. Results A total of 219 participants completed the study with a mean age of 31.73 ± 12.46. The prevalence of dental caries and tobacco was found to be 80.36% and 5.02% respectively. Participants without health insurance had 2.35 times higher odds of dental caries (95% CI: 1.03–5.36). Not rinsing the mouth after eating sweets was associated with 3.07 times higher odds of dental caries (95% CI: 1.31–7.18). Those who hadn’t visited a dentist in the past 12 months had lower odds (0.42; 95% CI: 0.18–0.94). Eating fresh fruit daily showed statistically higher odds (2.70; 95% CI: 1.04–6.99) of dental caries. Non-tobacco users had higher odds (14.19; 2.55–78.99) of dental caries. Conclusion Dental caries is highly prevalent, while tobacco usage is relatively low. Factors associated with dental caries included lack of health insurance coverage, consumption of fruits once daily, recent dental visits within the past year, not rinsing the mouth with water after consuming sweets, and non-tobacco users

Carbon Dots in Treatment of Pediatric Brain Tumors: Past, Present, and Future Directions

Pediatric brain tumors remain a significant source of morbidity and mortality. Though developments have been made in treating these malignancies, the blood–brain barrier, intra- and inter-tumoral heterogeneity, and therapeutic toxicity pose challenges to improving outcomes. Varying types of nanoparticles, including metallic, organic, and micellar molecules of varying structures and compositions, have been investigated as a potential therapy to circumvent some of these inherent challenges. Carbon dots (CDs) have recently gained popularity as a novel nanoparticle with theranostic properties. This carbon-based modality is highly modifiable, allowing for conjugation to drugs, as well as tumor-specific ligands in an effort to more effectively target cancerous cells and reduce peripheral toxicity. CDs are being studied pre-clinically. The ClinicalTrials.gov site was queried using the search terms: brain tumor and nanoparticle, liposome, micelle, dendrimer, quantum dot, or carbon dot. At the time of this review, 36 studies were found, 6 of which included pediatric patients. Two of the six studies investigated nanoparticle drug formulations, whereas the other four studies were on varying liposomal nanoparticle formulations for the treatment of pediatric brain tumors. Here, we reviewed the context of CDs within the broader realm of nanoparticles, their development, promising pre-clinical potential, and proposed future translational utility

Carbon Dots: A Future Blood&ndash;Brain Barrier Penetrating Nanomedicine and Drug Nanocarrier

Wei Zhang,1,&ast; Ganesh Sigdel,1,&ast; Keenan J Mintz,1 Elif S Seven,1 Yiqun Zhou,1 Chunyu Wang,2,3 Roger M Leblanc1 1Department of Chemistry, University of Miami, Coral Gables, FL, 33146, USA; 2Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA; 3Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA&ast;These authors contributed equally to this workCorrespondence: Roger M Leblanc Email [email protected]: Drug delivery across the bloodâ\u80\u93brain barrier (BBB) is one of the biggest challenges in modern medicine due to the BBBâ\u80\u99s highly semipermeable property that limits most therapeutic agents of brain diseases to enter the central nervous system (CNS). In recent years, nanoparticles, especially carbon dots (CDs), exhibit many unprecedented applications for drug delivery. Several types of CDs and CD-ligand conjugates have been reported successfully penetrating the BBB, which shows a promising progress in the application of CD-based drug delivery system (DDS) for the treatment of CNS diseases. In this review, our discussion of CDs includes their classification, preparations, structures, properties, and applications for the treatment of neurodegenerative diseases, especially Alzheimerâ\u80\u99s disease (AD) and brain tumor. Moreover, abundant functional groups on the surface, especially amine and carboxyl groups, allow CDs to conjugate with diverse drugs as versatile drug nanocarriers. In addition, structure of the BBB is briefly described, and mechanisms for transporting various molecules across the BBB and other biological barriers are elucidated. Most importantly, recent developments in drug delivery with CDs as BBB-penetrating nanodrugs and drug nanocarriers to target CNS diseases especially Alzheimerâ\u80\u99s disease and brain tumor are summarized. Eventually, future prospects of the CD-based DDS are discussed in combination with the development of artificial intelligence and nanorobots.Keywords: carbon dots, bloodâ\u80\u93brain barrier, drug delivery, brain tumor, central nervous system disease

Carbon Dots: A Future Blood–Brain Barrier Penetrating Nanomedicine and Drug Nanocarrier

Drug delivery across the blood–brain barrier (BBB) is one of the biggest challenges in modern medicine due to the BBB’s highly semipermeable property that limits most therapeutic agents of brain diseases to enter the central nervous system (CNS). In recent years, nanoparticles, especially carbon dots (CDs), exhibit many unprecedented applications for drug delivery. Several types of CDs and CD-ligand conjugates have been reported successfully penetrating the BBB, which shows a promising progress in the application of CD-based drug delivery system (DDS) for the treatment of CNS diseases. In this review, our discussion of CDs includes their classification, preparations, structures, properties, and applications for the treatment of neurodegenerative diseases, especially Alzheimer’s disease (AD) and brain tumor. Moreover, abundant functional groups on the surface, especially amine and carboxyl groups, allow CDs to conjugate with diverse drugs as versatile drug nanocarriers. In addition, structure of the BBB is briefly described, and mechanisms for transporting various molecules across the BBB and other biological barriers are elucidated. Most importantly, recent developments in drug delivery with CDs as BBB-penetrating nanodrugs and drug nanocarriers to target CNS diseases especially Alzheimer’s disease and brain tumor are summarized. Eventually, future prospects of the CD-based DDS are discussed in combination with the development of artificial intelligence and nanorobots

Interfacial behavior of Proteinase K enzyme at air-saline subphase

[Display omitted] This study investigates the interfacial behavior of the proteinase K enzyme at air–water interface. Adsorption of enzyme on the surface was induced using saline subphase. The surface packing and stability of the enzyme was investigated using of surface pressure-area (π-A) and surface potential-area (ΔV-A) isotherms. Proteinase K enzyme forms film at air-aqueous interface and demonstrates good stability as shown through compression-decompression cycle experiments. To characterize the surface assembly morphology of the interfacial enzymes UV–vis and fluorescence spectroscopic techniques were used. The data revealed that the enzyme Langmuir monolayer has good homogeneity with no evidence of aggregates during compression. The secondary structure of the enzyme at interface was determined to be α-helix using p-polarized infrared-reflection absorption spectroscopy. This was confirmed through Circular dichroism spectra of the enzyme Langmuir-Blodgett (LB) film which showed that the major conformation present were α-helices