A Review on Nanoparticles: Preparation and Characterization of Nanoparticles

Author(s):  
Saloni Manglik ◽  
Jaya Singh

The development of innovative medication delivery systems has increased at an exponential rate in the last few years. Nanoparticles are particles with a size of between one and one hundred nanometers. Nanoparticles provide substantial benefits over conventional drug administration in terms of high bioavailability, high stability, high drug-carrying capacity, and other characteristics. This review concentrated mostly on the classification of nanoparticles, the technique of synthesis, the evaluation of nanoparticles, and the list of FDA-approved nanomedicines now available on the market.

Author(s):  
I.G.C. Kerr ◽  
J.M. Williams ◽  
W.D. Ross ◽  
J.M. Pollard

The European rabbit (Oryctolagus cuniculus) introduced into New Zealand in the 183Os, has consistently flourished in Central Otago, the upper Waitaki, and inland Marlborough, all areas of mediterranean climate. It has proved difficult to manage in these habitats. The 'rabbit problem' is largely confined to 105,000 ha of low producing land mostly in semi arid areas of Central Otago. No field scale modifications of the natural habitat have been successful in limiting rabbit numbers. The costs of control exceed the revenue from the land and continued public funding for control operations appears necessary. A system for classifying land according to the degree of rabbit proneness is described. Soil survey and land classification information for Central Otago is related to the distribution and density of rabbits. This intormation can be used as a basis for defining rabbit carrying capacity and consequent land use constraints and management needs. It is concluded that the natural rabbit carrying capacity of land can be defined by reference to soil survey information and cultural modification to the natural vegetation. Classification of land according to rabbit proneness is proposed as a means of identifying the need for, and allocation of, public funding tor rabbit management. Keywords: Rabbit habitat, rabbit proneness, use of rabbit prone land.


Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 640
Author(s):  
Natalia R. Moyetta ◽  
Fabián O. Ramos ◽  
Jimena Leyria ◽  
Lilián E. Canavoso ◽  
Leonardo L. Fruttero

Hemocytes, the cells present in the hemolymph of insects and other invertebrates, perform several physiological functions, including innate immunity. The current classification of hemocyte types is based mostly on morphological features; however, divergences have emerged among specialists in triatomines, the insect vectors of Chagas’ disease (Hemiptera: Reduviidae). Here, we have combined technical approaches in order to characterize the hemocytes from fifth instar nymphs of the triatomine Dipetalogaster maxima. Moreover, in this work we describe, for the first time, the ultrastructural features of D. maxima hemocytes. Using phase contrast microscopy of fresh preparations, five hemocyte populations were identified and further characterized by immunofluorescence, flow cytometry and transmission electron microscopy. The plasmatocytes and the granulocytes were the most abundant cell types, although prohemocytes, adipohemocytes and oenocytes were also found. This work sheds light on a controversial aspect of triatomine cell biology and physiology setting the basis for future in-depth studies directed to address hemocyte classification using non-microscopy-based markers.


Landslides ◽  
2021 ◽  
Author(s):  
Chiara Crippa ◽  
Elena Valbuzzi ◽  
Paolo Frattini ◽  
Giovanni B. Crosta ◽  
Margherita C. Spreafico ◽  
...  

AbstractLarge slow rock-slope deformations, including deep-seated gravitational slope deformations and large landslides, are widespread in alpine environments. They develop over thousands of years by progressive failure, resulting in slow movements that impact infrastructures and can eventually evolve into catastrophic rockslides. A robust characterization of their style of activity is thus required in a risk management perspective. We combine an original inventory of slow rock-slope deformations with different PS-InSAR and SqueeSAR datasets to develop a novel, semi-automated approach to characterize and classify 208 slow rock-slope deformations in Lombardia (Italian Central Alps) based on their displacement rate, kinematics, heterogeneity and morphometric expression. Through a peak analysis of displacement rate distributions, we characterize the segmentation of mapped landslides and highlight the occurrence of nested sectors with differential activity and displacement rates. Combining 2D decomposition of InSAR velocity vectors and machine learning classification, we develop an automatic approach to characterize the kinematics of each landslide. Then, we sequentially combine principal component and K-medoids cluster analyses to identify groups of slow rock-slope deformations with consistent styles of activity. Our methodology is readily applicable to different landslide datasets and provides an objective and cost-effective support to land planning and the prioritization of local-scale studies aimed at granting safety and infrastructure integrity.


2021 ◽  
Vol 3 (3) ◽  
pp. 376-388
Author(s):  
Francisco J. Sevilla ◽  
Andrea Valdés-Hernández ◽  
Alan J. Barrios

We perform a comprehensive analysis of the set of parameters {ri} that provide the energy distribution of pure qutrits that evolve towards a distinguishable state at a finite time τ, when evolving under an arbitrary and time-independent Hamiltonian. The orthogonality condition is exactly solved, revealing a non-trivial interrelation between τ and the energy spectrum and allowing the classification of {ri} into families organized in a 2-simplex, δ2. Furthermore, the states determined by {ri} are likewise analyzed according to their quantum-speed limit. Namely, we construct a map that distinguishes those ris in δ2 correspondent to states whose orthogonality time is limited by the Mandelstam–Tamm bound from those restricted by the Margolus–Levitin one. Our results offer a complete characterization of the physical quantities that become relevant in both the preparation and study of the dynamics of three-level states evolving towards orthogonality.


Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 733
Author(s):  
Nobutaka Ebata ◽  
Masashi Fujita ◽  
Shota Sasagawa ◽  
Kazuhiro Maejima ◽  
Yuki Okawa ◽  
...  

Gallbladder cancer (GBC), a rare but lethal disease, is often diagnosed at advanced stages. So far, molecular characterization of GBC is insufficient, and a comprehensive molecular portrait is warranted to uncover new targets and classify GBC. We performed a transcriptome analysis of both coding and non-coding RNAs from 36 GBC fresh-frozen samples. The results were integrated with those of comprehensive mutation profiling based on whole-genome or exome sequencing. The clustering analysis of RNA-seq data facilitated the classification of GBCs into two subclasses, characterized by high or low expression levels of TME (tumor microenvironment) genes. A correlation was observed between gene expression and pathological immunostaining. TME-rich tumors showed significantly poor prognosis and higher recurrence rate than TME-poor tumors. TME-rich tumors showed overexpression of genes involved in epithelial-to-mesenchymal transition (EMT) and inflammation or immune suppression, which was validated by immunostaining. One non-coding RNA, miR125B1, exhibited elevated expression in stroma-rich tumors, and miR125B1 knockout in GBC cell lines decreased its invasion ability and altered the EMT pathway. Mutation profiles revealed TP53 (47%) as the most commonly mutated gene, followed by ELF3 (13%) and ARID1A (11%). Mutations of ARID1A, ERBB3, and the genes related to the TGF-β signaling pathway were enriched in TME-rich tumors. This comprehensive analysis demonstrated that TME, EMT, and TGF-β pathway alterations are the main drivers of GBC and provides a new classification of GBCs that may be useful for therapeutic decision-making.


2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Antonio Marra ◽  
Dario Trapani ◽  
Giulia Viale ◽  
Carmen Criscitiello ◽  
Giuseppe Curigliano

Abstract Triple-negative breast cancer (TNBC) is not a unique disease, encompassing multiple entities with marked histopathological, transcriptomic and genomic heterogeneity. Despite several efforts, transcriptomic and genomic classifications have remained merely theoretic and most of the patients are being treated with chemotherapy. Driver alterations in potentially targetable genes, including PIK3CA and AKT, have been identified across TNBC subtypes, prompting the implementation of biomarker-driven therapeutic approaches. However, biomarker-based treatments as well as immune checkpoint inhibitor-based immunotherapy have provided contrasting and limited results so far. Accordingly, a better characterization of the genomic and immune contexture underpinning TNBC, as well as the translation of the lessons learnt in the metastatic disease to the early setting would improve patients’ outcomes. The application of multi-omics technologies, biocomputational algorithms, assays for minimal residual disease monitoring and novel clinical trial designs are strongly warranted to pave the way toward personalized anticancer treatment for patients with TNBC.


Author(s):  
David Song ◽  
Ashish Gupta ◽  
Chia-Pin Chiu

This paper presents the current-carrying-capacity (CCC) characterization of a land-grid-array type microprocessor socket. This CCC study has been performed using both computational modeling and experiments using infrared camera. A subsequent risk assessment was performed against the maximum allowed temperature at the point of pressure contact of socket pin for the use-condition socket pin current and motherboard temperature. The results from the modeling and the experimental results are compared.


Author(s):  
Pandey Swarnima ◽  
Sushant Kumar

The paper is aimed to provide a comprehensive review on nanoparticles, methods of preparation, applications in drug delivery. In recent years, there has been an exponential interest within the development of novel drug delivery systems using nanoparticles. Nanoparticles offers significant advantages over the conventional drug delivery in terms of high stability, high specificity, high drug carrying capacity, ability for controlled release, possibility to use in several route of administration and therefore the capability to deliver both hydrophilic and hydrophobic drug molecules. This review focuses on classification, methods of preparation, characterization, application, advantages of nanoparticles and health perspectives.


2021 ◽  
Vol 2 (1) ◽  
pp. 49-55
Author(s):  
E U Iwuozo ◽  
J O Enyikwola ◽  
I O Obekpa ◽  
O O Ijachi ◽  
A A Godwin ◽  
...  

Electroencephalography (EEG) remains an important investigative tool in supporting the diagnosis and classification of various seizure types. We sought to examine and characterize the EEG findings from all patients referred for the procedure. This cross-sectional retrospective study was carried out at an EEG unit in Federal Medical Centre, Makurdi, Benue State, North Central Nigeria from May 2016 to December 2020. Relevant patients' information were extracted and analysed using SPSS version 21. A total of 484 patients were seen over the study period with age range of 1-87 years and median age of 23 years. They comprised of 254 (52.5%) male and 230 (47.5%) female. The psychiatrist and the Physicians/Neurologist referred most of them for EEG, 201 (41.5%) and 124 (25.6%) respectively. The most reported indication for EEG was clinical suspicion of seizure disorder 291 (60.1%), whilst some did not have a clear indication 111 (22.9%). About 417 (86.2%) of our patients had abnormal EEG finding out of which 414 (99.3%) were diagnostic of seizure disorder made up of generalized seizure in 255 (61.6%) and focal seizure in 159 (38.4%). About 237 (48.9%) of them were already on antiepileptic drugs (AEDs) at referral of which 190 (80.2%0 were taking carbamazepine. This study showed a high prevalence of abnormal EEG with most of them diagnostic of seizure disorder especially generalized seizure. They were mostly of younger age group with about half of them already on AEDs at referral, majority of who were sent by the Psychiatrist.


Solid Earth ◽  
2015 ◽  
Vol 6 (2) ◽  
pp. 583-594 ◽  
Author(s):  
E. L. Poelking ◽  
C. E. R. Schaefer ◽  
E. I. Fernandes Filho ◽  
A. M. de Andrade ◽  
A. A. Spielmann

Abstract. Integrated studies on the interplay between soils, periglacial geomorphology and plant communities are crucial for the understanding of climate change effects on terrestrial ecosystems of maritime Antarctica, one of the most sensitive areas to global warming. Knowledge on physical environmental factors that influence plant communities can greatly benefit studies on the monitoring of climate change in maritime Antarctica, where new ice-free areas are being constantly exposed, allowing plant growth and organic carbon inputs. The relationship between topography, plant communities and soils was investigated on Potter Peninsula, King George Island, maritime Antarctica. We mapped the occurrence and distribution of plant communities and identified soil–landform–vegetation relationships. The vegetation map was obtained by classification of a QuickBird image, coupled with detailed landform and characterization of 18 soil profiles. The sub-formations were identified and classified, and we also determined the total elemental composition of lichens, mosses and grasses. Plant communities on Potter Peninsula occupy 23% of the ice-free area, at different landscape positions, showing decreasing diversity and biomass from the coastal zone to inland areas where sub-desert conditions prevail. There is a clear dependency between landform and vegetated soils. Soils that have greater moisture or are poorly drained, and with acid to neutral pH, are favourable for moss sub-formations. Saline, organic-matter-rich ornithogenic soils of former penguin rookeries have greater biomass and diversity, with mixed associations of mosses and grasses, while stable felsenmeers and flat rocky cryoplanation surfaces are the preferred sites for Usnea and Himantormia lugubris lichens at the highest surface. Lichens sub-formations cover the largest vegetated area, showing varying associations with mosses.


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