Physiological Homeostasis Alteration and Cellular Structure Damage of Chlorella Vulgaris Exposed to Silver Nanoparticles with Various Microstructure Morphologies

Abstract The toxicity of silver nanoparticles (AgNPs) with single morphology exposed to aquatic organisms had been well revealed in the past decade, but few studies have been carried out to evaluate the toxicity differences between AgNPs with various microstructure morphologies, especially to algae. In this work, Chlorella vulgaris was used as the tested organism to illustrate the differences of toxic effects between silver nanospheres (AgNSs), silver nanocubes (AgNCs) and silver nanoplates (AgPLs) with concentration of 0.5, 1.0, 2.0, 5.0 mg⸳L-1, based on the algae’s growth (72h), chlorophyll-a content, antioxidant enzyme activity, lipid peroxidation and cell apoptosis (48h). The results showed that the toxicity level exposed to Chlorella vulgaris was in the order of AgPLs> AgNCs> AgNSs. The difference shown indicated that the potential toxicity of AgNPs is primarily depended on their microstructure morphologies. This current study initially revealed the structure-effects of AgNPs on Chlorella vulgaris, provided a scientific basis for aquatic environmental risk assessment.

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Effect of Silver Nanoparticles on Aquatic Organisms

Letters in Applied NanoBioScience ◽

10.33263/lianbs101.20122015 ◽

2020 ◽

Vol 10 (1) ◽

pp. 2012-2015

Keyword(s):

Silver Nanoparticles ◽

Aquatic Ecosystem ◽

Aquatic Invertebrates ◽

Aquatic Organisms ◽

Aquatic Organism ◽

Neurological Impairment ◽

Trophic Levels ◽

Direct Impact ◽

The Past ◽

The Impact

Silver nanoparticles are extensively used in the past few years. The presence of these silver nanoparticles concerns the risks they pose to the environment as a whole. Their tiny size and higher surface area make them a very potent threat in the aquatic ecosystem. The interactions and bioaccumulation in the aquatic ecosystem have led to disturbances in the food chain of the aquatic organism. The silver nanoparticles have caused biochemical, physiological, morphological, and neurological impairment in the aquatic organisms. There are several studies that not only report the direct impact of these AgNPs on the water bodies but also report the impact of ligand-bound AgNPs on aquatic invertebrates at different trophic levels and different medium. This literature review attempts to integrate recent findings on the impact of silver nanoparticles and associated studies on aquatic organisms.

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Smart Estimation Ver-H.1.0

10.31227/osf.io/2tyqk ◽

2018 ◽

Author(s):

Sigit Haryadi

Keyword(s):

Sample Size ◽

Confidence Level ◽

Time Span ◽

Regression Equation ◽

Weight Factor ◽

The Past ◽

Level Of Confidence ◽

The Future ◽

Future Value ◽

The Difference

We cannot be sure exactly what will happen, we can only estimate by using a particular method, where each method must have the formula to create a regression equation and a formula to calculate the confidence level of the estimated value. This paper conveys a method of estimating the future values, in which the formula for creating a regression equation is based on the assumption that the future value will depend on the difference of the past values divided by a weight factor which corresponding to the time span to the present, and the formula for calculating the level of confidence is to use "the Haryadi Index". The advantage of this method is to remain accurate regardless of the sample size and may ignore the past value that is considered irrelevant.

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Nondestructive Detection of the Gel State of Preserved Eggs Based on Dielectric Impedance

Foods ◽

10.3390/foods10020394 ◽

2021 ◽

Vol 10 (2) ◽

pp. 394

Author(s):

Cheng-Han Li ◽

Chun-Hung Hsieh ◽

Cheng-Chu Hung ◽

Ching-Wei Cheng

Keyword(s):

Decay Rate ◽

Mechanical Vibration ◽

Scientific Basis ◽

Nondestructive Method ◽

Inspection System ◽

Nyquist Diagram ◽

Detection Technology ◽

The Difference ◽

The Individual

After completing the production of preserved eggs, traditionally, the degree of gelling is judged by allowing workers to tap the preserved eggs with their fingers and sense the resulting oscillations. The amount of oscillation is used for the quality classification. This traditional method produces varying results owing to the differences in the sensitivity of the individual workers, who are not objective. In this study, dielectric detection technology was used to classify the preserved eggs nondestructively. The impedance in the frequency range of 2–300 kHz was resolved into resistance and reactance, and was plotted on a Nyquist diagram. Next, the diagram curve was fitted in order to obtain the equivalent circuit, and the difference in the compositions of the equivalent circuits corresponding to gelled and non-gelled preserved eggs was analyzed. A preserved egg can be considered an RLC series circuit, and its decay rate is consistent with the decay rate given by mechanical vibration theory. The Nyquist diagrams for the resistance and reactance of preserved eggs clearly showed that the resistance and reactance of gelled and non-gelled eggs were quite different, and the classification of the eggs was performed using Bayesian network (BN). The results showed that a BN classifier with two variables, i.e., resistance and reactance, can be used to classify preserved eggs as gelled or non-gelled, with an accuracy of 81.0% and a kappa value of 0.62. Thus, a BN classifier based on resistance and reactance demonstrates the ability to classify the quality of preserved egg gel. This research provides a nondestructive method for the inspection of the quality of preserved egg gel, and provides a theoretical basis for the development of an automated preserved egg inspection system that can be used as the scientific basis for the determination of the quality of preserved eggs.

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Performance Assessment Study of Indian Railways – Case of Low Efficiencies in Large Government Monopoly

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211025516 ◽

2021 ◽

pp. 036119812110255

Author(s):

Sabyasachi S. Roy ◽

Mukul Kulshrestha

Keyword(s):

Scientific Basis ◽

Data Envelopment ◽

Policy Reforms ◽

Management Planning ◽

Rail Network ◽

The Past ◽

Assessment Study ◽

Micro Level ◽

Global Population ◽

Financial Losses

Indian Railways is the world’s largest government-owned monopoly, annually carrying passenger numbers that surpass the global population. It is world’s fourth largest rail network after the U.S.A., China, and Russia, and is managed by a separate Ministry of Railways. The operating ratios have consistently been around 90% in the past several years, indicating that that the capability to generate operational surplus is low. Further, its expenditure on staff and their pensions has been increasing. Consequently, capacity growth is increasingly being funded through borrowings, which threatens to further worsen the financial situation. Thus, railway services in India are often perceived as being inefficient and unsatisfactory. However, this perception of inefficient services has no scientific basis as mid- and micro-level efficiency analyses of Indian Railways have never been carried out. This paper adopts a data envelopment analysis (DEA)-based approach to evaluate the performance efficiencies of the 69 divisions of Indian Railways. Six models that deploy a range of performance indicators like operating expenditures, numbers of staff employed or passengers carried, freight carried, rail network length, and revenues generated have been employed to assess efficiencies. The results demonstrate the existence of significant inefficiencies that may possibly be attributed to lack of proper management, planning policies, and mis-governance, resulting in significant financial losses. The paper discusses these issues and the policy reforms needed in the developing country context, while suggesting some reforms that may lead to improved sector performances.

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Microwave-assisted green synthesis of silver nanoparticles using dried extracts of Chlorella vulgaris and antibacterial activity studies

Green Processing and Synthesis ◽

10.1515/gps-2020-0024 ◽

2020 ◽

Vol 9 (1) ◽

pp. 283-293

Author(s):

Milad Torabfam ◽

Meral Yüce

Keyword(s):

Silver Nanoparticles ◽

Green Synthesis ◽

Chlorella Vulgaris ◽

Metallic Nanoparticles ◽

Nitrate Solution ◽

Spherical Shape ◽

Silver Nitrate Solution ◽

Spectroscopy Analysis ◽

Bacterial Diseases ◽

Serovar Typhimurium

AbstractGreen synthesis of metallic nanoparticles (NPs) is acquiring considerable attention due to its environmental and economic superiorities over other methods. This study describes the practical synthesis of silver nanoparticles (AgNPs) through the reduction of silver nitrate solution using an algal source, Chlorella vulgaris, as the reducing as well as the stabilizing agent. The energy required for this synthesis was supplied by microwave radiation. The ultraviolet-visible spectroscopy exhibited a single peak related to the surface plasmon absorbance of AgNPs at 431 nm. The AgNPs with high stability (a zeta potential of −17 mV), hydrodynamic size distribution of 1–50 nm, and mostly spherical shape were obtained through a 10 min process. Fourier transform infrared spectroscopy analysis revealed that several functional groups, including carbonyl groups of C. vulgaris, play a significant role in the formation of functional NPs. Antibacterial features of the produced AgNPs were verified against those of Salmonella enterica subsp. enterica serovar typhimurium and Staphylococcus aureus, demonstrating a considerable growth inhibition at increasing concentrations of the NPs. As a result, the formed AgNPs can be used as a promising agent against bacterial diseases.

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Size-controlled fabrication of silver nanoparticles using the Hedyotis puberula leaf extract: toxicity on mosquito vectors and impact on biological control agents

RSC Advances ◽

10.1039/c6ra23208f ◽

2016 ◽

Vol 6 (99) ◽

pp. 96573-96583 ◽

Cited By ~ 7

Author(s):

Raja Mohamed Sait Thameem Azarudeen ◽

Marimuthu Govindarajan ◽

Abubucker Amsath ◽

Shine Kadaikunnan ◽

Naiyf S. Alharbi ◽

...

Keyword(s):

Biological Control ◽

Silver Nanoparticles ◽

Leaf Extract ◽

Low Cost ◽

Aquatic Organisms ◽

Capping Agent ◽

Mosquito Vectors ◽

Biological Control Agents ◽

Size Controlled ◽

Control Tool

As a low-cost and eco-friendly control tool, Ag nanoparticles were fabricated usingHedyotis puberulaaqueous extract as a reducing and capping agent and showed potent activity against malaria and arbovirus vectors with low biotoxicity against non-target aquatic organisms.

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The Burden of the Nondiversifiable Risk of Entrepreneurship

The American Economic Review ◽

10.1257/aer.100.3.1163 ◽

2010 ◽

Vol 100 (3) ◽

pp. 1163-1194 ◽

Cited By ~ 132

Author(s):

Robert E Hall ◽

Susan E Woodward

Keyword(s):

Relative Risk ◽

Risk Aversion ◽

Venture Capital ◽

Dynamic Program ◽

Certainty Equivalent ◽

Important Class ◽

Relative Risk Aversion ◽

The Past ◽

Equity Value ◽

The Difference

Entrepreneurship is risky. We study the risk facing a well-documented and important class of entrepreneurs, those backed by venture capital. Using a dynamic program, we calculate the certainty-equivalent of the difference between the cash rewards that entrepreneurs actually received over the past 20 years and the cash that entrepreneurs would have received from a risk-free salaried job. The payoff to a venture-backed entrepreneur comprises a below-market salary and a share of the equity value of the company when it goes public or is acquired. We find that the typical venture-backed entrepreneur received an average of $5.8 million in exit cash. Almost three-quarters of entrepreneurs receive nothing at exit and a few receive over a billion dollars. Because of the extreme dispersion of payoffs, an entrepreneur with a coefficient of relative risk aversion of two places a certainty equivalent value only slightly greater than zero on the distribution of outcomes she faces at the time of her company's launch. (JEL G24, G32, L26, M13)

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The Flynn Effect

Character Lab Tips ◽

10.53776/tips-the-flynn-effect ◽

2018 ◽

Author(s):

Angela Duckworth ◽

Keyword(s):

Graduate School ◽

The United States ◽

Delay Of Gratification ◽

Average Score ◽

Past Century ◽

Political Scientist ◽

Abstract Reasoning ◽

Flynn Effect ◽

The Past ◽

The Difference

In tandem with increases in delay of gratification, the human capacity for abstract reasoning has increased enormously over the past century. This phenomenon is called the Flynn Effect, after the political scientist who discovered it. I first learned about the Flynn Effect in graduate school. I remember thinking it was impossible. How could it be that as a species, we're getting smarter? And not just a little bit smarter. The size of the Flynn Effect is staggering: more than 30 IQ points—the difference between getting an average score on a standard intelligence test versus qualifying as mentally gifted. Gains are comparable in all areas of the United States and, indeed, around the world.

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Avoiding Psychiatric Disability Overdiagnosis, Part 1: General Disability and Occupational Disability—Going Beyond Medical Impairment Assessments

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2021.julaug01 ◽

2021 ◽

Vol 26 (4) ◽

pp. 3-7

Author(s):

Fabien Gagnon ◽

Les Kertay

Keyword(s):

Mental Health ◽

Work Disability ◽

Well Being ◽

Psychiatric Disability ◽

Disability Assessment ◽

Health Work ◽

Occupational Disability ◽

The Past ◽

The Difference ◽

Mental Health Work

Abstract Claims of occupational psychiatric disability have increased considerably over the past 20 years. To avoid psychiatric disability overdiagnosis, it is important to improve the clinical assessment of mental health work disability. This article discusses general disability issues and their impact on individual well-being, social participation, and frequently associated poverty. It defines the difference between impairment assessment and disability assessment, explores three common disability models, and raises issues about psychiatric disability and its potential overdiagnosis.

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Frequency of deep convective clouds in the tropical zone from 10 years of AIRS data

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-10795-2013 ◽

2013 ◽

Vol 13 (21) ◽

pp. 10795-10806 ◽

Cited By ~ 23

Author(s):

H. H. Aumann ◽

A. Ruzmaikin

Keyword(s):

Brightness Temperature ◽

Frequency Of Occurrence ◽

Tropical Zone ◽

Convective Clouds ◽

The Past ◽

Atmospheric Window ◽

Deep Convective Clouds ◽

Sst Anomaly ◽

The Difference ◽

Global Precipitation

Abstract. Deep convective clouds (DCCs) have been widely studied because of their association with heavy precipitation and severe weather events. Changes in the properties of DCCs are likely in a changing climate. Ten years of data collected by Atmospheric Infrared Sounder (AIRS) allow us to identify decadal trends in frequency of occurrence of DCCs over land and ocean. In the past, DCCs have been identified in the thermal infrared by three methods: (1) thresholds based on the absolute value of an atmospheric window channel brightness temperature; (2) thresholds based on the difference between the brightness temperature in an atmospheric window channel and the brightness temperature centered on a strong water vapor absorption line; and (3) a threshold using the difference between the window channel brightness temperature and the tropopause temperature based on climatology. Simultaneous observations of these infrared identified DCCs with the Advanced Microwave Sounding Unit–Humidity Sounder for Brazil (AMSU-HSB) using 183 GHz water channels provide a statistical correlation with microwave deep convection and overshooting convection. In the past 10 years, the frequency of occurrence of DCCs has decreased for the tropical ocean, while it has increased for tropical land. The area of the tropical zone associated with DCCs is typically much less than 1%. We find that the least frequent, more extreme DCCs show the largest trend in frequency of occurrence, increasing over land and decreasing over ocean. The trends for land and ocean closely balance, such that the DCC frequency changed at an insignificant rate for the entire tropical zone. This pattern of essentially zero trend for the tropical zone, but opposite land/ocean trends, is consistent with measurements of global precipitation. The changes in frequency of occurrence of the DCCs are correlated with the Niño34 index, which defines the sea surface temperature (SST) anomaly in the east-central Pacific. This is also consistent with patterns seen in global precipitation. This suggests that the observed changes in the frequency are part of a decadal variability characterized by shifts in the main tropical circulation patterns, which does not fully balance in the 10-year AIRS data record. The regional correlations and anti-correlations of the DCC frequency anomaly with the Multivariate ENSO Index (MEI) provide a new perspective for the regional analysis of past events, since the SST anomaly in the Nino34 region is available in the form of the extended MEI from 1871.

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