Occurrence and characterization of pearls from oysters of the genus Crassostrea

2016 ◽  
Vol 97 (2) ◽  
pp. 297-302
Author(s):  
Frederico M. Batista ◽  
Ana Grade ◽  
Deborah M. Power ◽  
Francisco Ruano ◽  
Elizabeth M. Harper
Keyword(s):  
Oyster Shell ◽  
X Ray Diffraction ◽  
Parasitic Copepods ◽  
Ria Formosa ◽  
Crassostrea Angulata ◽  
Mollusc Species ◽  
Southern Portugal ◽  
Foot Disease ◽  
The Right ◽  
Almost All

The occurrence of pearls in the ‘true’ oysters, the Ostreioidea, is poorly documented despite being the most produced mollusc species in the world. Oysters of the Crassostrea genus were collected in two different sites in southern Portugal where both Crassostrea angulata and C. gigas are present, namely in: (1) the Ria Formosa lagoon where pearls were not observed (N = 446); and (2) the Guadiana estuary where pearls were found in 12 out of the 798 oysters analysed. The pearls were located mainly at the edge of the right mantle lobe in the inhalant chamber and their maximum length ranged from 0.9 to 5.5 mm. Almost all the pearls had a white-cream colouration with the exception of two pearls that had a black-brown colour. X-ray diffraction analysis of one pearl showed that it was entirely calcitic with no traces of either aragonite or vaterite. The pearls observed were therefore non-nacreous pearls. Scanning electron microscopy (SEM) revealed a diversity of microstructures including prismatic, foliae-like sheets and blocky textures, i.e. highly reminiscent of the host oyster shell microstructures. Parasites (e.g. parasitic copepods, Haplosporidium-like plasmodia) and signs of diseases (e.g. foot disease) were observed in some of the oysters analysed, but they were not associated with the occurrence of pearls. The present work is one of the few studies on the occurrence of natural pearls in ‘true’ oysters and to our knowledge the first description of their microstructure by SEM.

scholarly journals Development of central auditory processes in Polish children and adolescents at the age from 7 to 16 years

2021 ◽  
Author(s):  
Monika Lewandowska ◽  
Rafał Milner ◽  
Małgorzata Ganc ◽  
Elżbieta Włodarczyk ◽  
Joanna Dołżycka ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
School Students ◽  
Frequency Pattern ◽  
Speech In Noise ◽  
Age Related ◽  
Right Ear Advantage ◽  
The Right ◽  
Almost All ◽  
Test Retest Reliability ◽  
Auditory Processes

AbstractThere are discrepancies in the literature regarding the course of central auditory processes (CAP) maturation in typically developing children and adolescents. The purpose of the study was to provide an overview of age – related improvement in CAP in Polish primary and secondary school students aged 7–16 years. 180 children/adolescents, subdivided into 9 age categories, and 20 adults (aged 18–24 years) performed the Dichotic Digit Test (DDT), Duration Pattern Test (DPT), Frequency Pattern Test (FPT), Gap Detection Test (GDT) and adaptive Speech-in-Noise (aSpN). The 12-year-olds was retested after w week. We found the age effects only for the DDT, DPT and FPT. In the right ear DDT the 7-year-olds performed more poorly than all groups ≥12. In the left ear DDT both 7- and 8-year-olds achieved less correct responses compared with the 13-, 14-, 15-year-olds and with the adults. The right ear advantage was greater in the 7-year-olds than in the 15-year-olds and adult group. At the age of 7 there was lower DPT and FPT scores than in all participants ≥13 whereas the 8-year-olds obtained less correct responses in the FPT than all age categories ≥12. Almost all groups (except for the 7-year-olds) performed better in the DPT than FPT. The test-retest reliability for all tests was satisfactory. The study demonstrated that different CAP have their own patterns of improvement with age and some of them are specific for the Polish population. The psychoacoustic battery may be useful in screening for CAP disorders in Poland.

scholarly journals Sulbactam pivoxil powder attributes and compatibility study with excipients

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Loreana C. Gallo ◽  
Noelia L. Gonzalez Vidal ◽  
Fabio F. Ferreira ◽  
María V. Ramírez-Rigo
Keyword(s):  
Thermal Analyses ◽  
Oral Route ◽  
Endothermic Peak ◽  
Compatibility Study ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Thermogravimetric Curve ◽  
Almost All ◽  
Potential Interactions ◽  
Lactamase Inhibitor

Abstract Background Sulbactam pivoxil is an irreversible β-lactamase inhibitor that can be used with β-lactam antibiotics to improve antibacterial therapy by the oral route. Relevant properties of this drug for pharmaceutical manufacturing are not available in the open literature. In this work, a solid-state characterization of sulbactam pivoxil at the molecular, particle, and bulk levels was performed. Results Particles exhibited a mean diameter of about 350 μm, irregular shape crystals, and good flow properties. This work presents for the first time the crystal structure of this β-lactamase inhibitor obtained by X-ray diffraction analysis. Fourier-transform infrared results showed the characteristic bands of aliphatic hydrocarbons and ester groups. The differential scanning calorimetry curve exhibited a sharp endothermic peak at 109 °C corresponding to sulbactam pivoxil melting. The thermogravimetric curve revealed a mass loss at 184 °C associated with a decomposition process. This powder showed a moisture content of 0.34% and a water activity of 0.463. Potential interactions between sulbactam pivoxil and common pharmaceutical excipients were evaluated by thermal analysis. The endothermic peak and the enthalpies of melting were preserved in almost all the analyzed mixtures. Conclusion The powder was constituted by micro-sized crystals of sulbactam pivoxil that had suitable physicochemical properties for processing in controlled humidity environments. Thermal analyses suggested that sulbactam pivoxil is compatible with most of the evaluated excipients. The information obtained in the present study is relevant for the development, manufacturing, and storage of formulations that include sulbactam pivoxil.

scholarly journals Bioinformatic tools help molecular characterization of Perkinsus olseni differentially expressed genes

2011 ◽  
Vol 8 (3) ◽  
pp. 130-140 ◽  
Author(s):  
Rita M. T. Ascenso
Keyword(s):  
Molecular Characterization ◽  
Protozoan Parasite ◽  
Bioinformatic Tools ◽  
Host Interaction ◽  
Ria Formosa ◽  
Genes Expression ◽  
Bioinformatic Tool ◽  
Southern Portugal ◽  
Heavy Mortality

Abstract In the 80ies, in Southern Europe and in particular in Ria Formosa there was an episode of heavy mortality of the economically relevant clam Ruditapes (R.) decussatus associated with a debilitating disease (Perkinsosis) caused by Perkinsus olseni. This protozoan parasite was poorly known concerning its’ differential transcriptome in response to its host, R. decussatus. This laboratory available protozoan system was used to identify parasite genes related to host interaction. Beyond the application of molecular biology technologies and methodologies, only the help of Bioinformatics tools allowed to analyze the results of the study. The strategy started with SSH technique, allowing the identification of parasite up-regulated genes in response to its natural host, then a macroarray was constructed and hybridized to characterize the parasite genes expression when exposed to bivalves hemolymph from permissive host (R. decussatus), resistant host (R. philippinarum) and non permissive bivalve (Donax trunculus) that cohabit in the same or adjacent habitats in Southern Portugal. Genes and respective peptides full molecular characterization depended on several Bioinformatic tools application. Also a new Bioinformatic tool was developed.

Synthesis of aligned carbon nanotubes in organic liquids

2002 ◽  
Vol 17 (9) ◽  
pp. 2457-2464 ◽  
Author(s):  
Yafei Zhang ◽  
Mikka N.-Gamo ◽  
Kiyoharu Nakagawa ◽  
Toshihiro Ando
Keyword(s):  
Carbon Nanotubes ◽  
Organic Liquid ◽  
Film Surface ◽  
Normal Pressure ◽  
Organic Liquids ◽  
X Ray Diffraction ◽  
Multiwalled Carbon ◽  
Aligned Carbon Nanotubes ◽  
Novel Method ◽  
The Right

A simple and novel method was developed for efficient synthesis of aligned multiwalled carbon nanotubes (CNTs) in methanol and ethanol under normal pressure. The CNTs' alignment and structures were investigated using Raman scattering and x-ray diffraction spectroscopy. A unique kind of coupled CNT was synthesized in which one rotated to the left and one rotated to the right. Chains periodically bridged the coupled CNTs. The growth mechanism of the CNTs within organic liquid is proposed to be a catalytic process at the Fe film surface in a dynamic and thermal nonequilibrium condition in organic liquids.

The Characteristic Evaluation of Hydroxyapatite Powders Synthesized from CaCO3 Refined from Oyster Shell and H3PO4

2006 ◽  
Vol 118 ◽  
pp. 639-644
Author(s):  
Hye Sung Kim ◽  
Su Chak Ryu
Keyword(s):  
Bone Density ◽  
Inductively Coupled Plasma ◽  
Oyster Shell ◽  
Atomic Emission ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Infra Red ◽  
Ft Ir

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) powders is synthesized using the mixed powders of CaCO3 refined from oyster shells and phosphoric acid (H3PO4-98%, Daejung) as starting materials. The characteristic evaluation and chemical analysis of the synthesized powders is performed by X-ray diffraction (XRD), Fourier-transformed infra-red spectroscopy (FT-IR), and inductively-coupled plasma atomic emission spectroscopy (ICPAES). XRD analysis of synthetic powder by heat treatment at 1300°C for 2hrs shows only HAp peaks corresponding to stoichiometric HAp. It is confirmed by ICP-AES test that impurities such as Zn, In, Ti, Ba, Cd, Pb, and Mn, is not detected at all, but small amounts of Ti and Be is observed (0.099ppm Ti and 0.002ppm Ba). Variation of bone density is measured by giving medication of HAp powder with drinking water into human body continuously for three month. After the medication, the bone density is higher than the medication before. This means that HAp powder made from this process can be used as improver of bone density.

Variation in fur farm and wild populations of the red fox, Vulpes vulpes (Carnivora: Canidae) — Part I: Morphometry

2016 ◽  
Vol 96 (4) ◽  
pp. 589-597 ◽  
Author(s):  
Magdalena Zatoń-Dobrowolska ◽  
Magdalena Moska ◽  
Anna Mucha ◽  
Heliodor Wierzbicki ◽  
Piotr Przysiecki ◽  
...  
Keyword(s):  
Vulpes Vulpes ◽  
Selective Breeding ◽  
Red Fox ◽  
Tail Length ◽  
Morphometric Traits ◽  
Red Foxes ◽  
Ear Height ◽  
Morphological Differences ◽  
The Right ◽  
Almost All

This paper demonstrates the influence of artificial selection on morphometric traits in the red fox [Vulpes vulpes (Linnaeus, 1758)]. Measurements and two proportion coefficients were analysed in 132 wild and 199 farm red foxes. The two groups differed significantly (P ≤ 0.05) on all but one of the measurements. Eight out of 11 measurements were significantly greater in the farm fox population, while only tail length, ear height, and length of the right hind limb were greater in the population of wild foxes. The opposite trend was observed when analysing variation in the measurements — the farm foxes were characterized by a greater variability only in the case of body weight, body length, and breadth of chest. When analysing the sexual dimorphism index in different sex and population groups, in almost all analysed traits, the greatest differences occurred between farm males and wild females. All of the traits examined in this study are important for survival of wild foxes. However, because importance of some traits was reduced during domestication and selective breeding (farm foxes do not have to fight for survival), the genetic relationship between them may have weakened. Other possible causes of morphological differences between the studied groups of red foxes are discussed as well.

Demonstration of the relationship between MSD and online learning during the COVID-19 pandemic

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kochu Therisa Karingada ◽  
Michael Sony
Keyword(s):  
Online Learning ◽  
Undergraduate Students ◽  
Online Survey ◽  
Cross Sectional Study ◽  
The Body ◽  
Body Parts ◽  
Cross Sectional ◽  
Content Type ◽  
The Right ◽  
Almost All

PurposeThe COVID-19 pandemic lockdown has caught many educational institutions by surprise and warranted an abrupt migration from offline to online learning. This has resulted in an education change, without any time for due consideration, as regards its impact on musculoskeletal disorders (MSD) on students. The purpose of this study is to investigate MSD related to online learning during the COVID-19 pandemic lockdown.Design/methodology/approachA cross-sectional study was conducted on undergraduate students in India. In total, 261 students participated in this online survey.FindingsThe study finds that around 80% of students have reported some symptom in the head, neck and eyes since they started online learning. In total, 58% have reported MSD symptom in the right shoulder and 56% in the right hand fingers. Besides, more than 40 % of students experienced some MSD symptoms, in almost all the body parts studied, due to online learning. Correlation analysis is conducted between time spent on online learning per day and MSD symptoms.Originality/valueThis is the first study conducted on MSD and online learning during COVID-19 pandemic.

TYPES OF OVERWORK AND JOBS THAT CANNOT BE OVERWORKED WITHIN THE FRAMEWORK OF THE LABOR LAW NO. 4857

2021 ◽  
Vol 6 (14) ◽  
pp. 67-81
Author(s):  
Altuğ YENGİNAR
Keyword(s):  
Labor Law ◽  
Working Hours ◽  
Human Right ◽  
International Human Rights ◽  
Right To Work ◽  
The Subject ◽  
The Republic ◽  
The Right ◽  
Almost All ◽  
Republic Of Turkey

The right to work has been recognized as a fundamental human right in almost all international human rights documents and in the constitutions of many countries. This right has been recognized and guaranteed as a fundamental human right also in the Constitution of the Republic of Turkey. However, not only recognizing and guaranteeing "work" as a fundamental human right but also regulating its implementation and functioning within the framework of laws is of great importance. The concept of overwork is a concept that has been mentioned in the Labor Law regarding the implementation and functioning of the concept of work and it is regulated in our Labor Law No. 4857. In order to talk about overwork, a limited working time is required. In this context, upon determining the maximum number of hours a worker can work per week by drawing a limit on working hours in Labor Law No. 4857, overwork, which is the subject of work exceeding this period, is defined. Furthermore, the types of overwork that arise depending on the reasons for overworking, as well as the jobs that cannot be overworked, are regulated in the same Law.

Pregnancies and Pregnancy Desires at the State Level: Estimates for 2017 and Trends Since 2012

2021 ◽  
Author(s):  
Kathryn Kost ◽  
◽  
Isaac Maddow-Zimet ◽  
Ashley C. Little
Keyword(s):  
Pregnancy Rate ◽  
Unwanted Pregnancy ◽  
State Level ◽  
The State ◽  
Clear Pattern ◽  
The South ◽  
The West ◽  
Key Points ◽  
The Right ◽  
Almost All

Key Points In almost all U.S. states, pregnancies reported as occurring at the right time or being wanted sooner than they occurred comprised the largest share of pregnancies in 2017, though proportions varied widely by state. The proportion of pregnancies that were wanted later or unwanted was higher in the South and Northeast than in other regions, and the proportion of pregnancies that occurred at the right time or were wanted sooner was higher in the West and Midwest. From 2012 to 2017, the wanted-later-or-unwanted pregnancy rate fell in the majority of states. However, no clear pattern emerged for any changes in the rate of pregnancies that were reported as wanted then or sooner or in the rate of those for which individuals expressed uncertainty.

scholarly journals Analisis Kandungan Klorofil Pada Anak Daun Tanaman Kelapa (Analysis of Chlorophyll Content in Children Leaves of Coconut Plants)

2019 ◽  
Vol 9 (2) ◽  
pp. 76
Author(s):  
Muhammad Tawary ◽  
Julius Pontoh ◽  
Lydia Momuat
Keyword(s):  
Chlorophyll Content ◽  
Chlorophyll A ◽  
Economic Value ◽  
Economic Benefits ◽  
Chlorophyll B ◽  
Solvent Extraction Method ◽  
Chlorophyll A And B ◽  
The Right ◽  
Almost All ◽  
Chlorophyll A Content

Analisis Kandungan Klorofil Pada Anak Daun Tanaman Kelapa (Analysis of Chlorophyll Content in Children Leaves of Coconut Plants) Muhammad Tawary1*), Julius Pontoh1), Lydia I.Momuat1)1)Jurusan Kimia, FMIPA UNSRAT Manado*Email korespondensi: [email protected] Diterima 7 Juli 2019, diterima untuk dipublikasi 10 Agustus 2019 Abstrak Tanaman kelapa banyak dibudidayakan sebagai tanaman pertanian. Tanaman kelapa memiliki nilai ekonomi yang tinggi karena hampir semua bagian tanaman kelapa memiliki manfaat ekonomis. Penelitian bertujuan untuk  mengembangkan metode analisis klorofil pada daun dan menentukan bagian anak daun yang memiliki kandungan klorofil tertinggi. Analisis kandungan klorofil dilakukan dengan metode ektraksi pelarut yang absorbansinya dibaca pada spektrofotometer UV-Vis. Kandungan klorofil a dalam daun bervariasi pada setiap bagian anak daun tanaman kelapa. Kandungan klorofil a pada posisi tengah anak daun kelapa (763.19 µmol/m2) dan kandungan klorofil b (196.22 µmol/m2). Kandungan klorofil a dan b pada setiap bagian anak daun dan posisi kanan dan kiri anak daun memiliki nilai yang relatif sama.Kata kunci: Kelapa, klorofil a, klorofil b Abstract Many coconut plants are cultivated as agricultural crops. Coconut plants have high economic value because almost all parts of coconut plants have economic benefits. The study aims to develop a method of chlorophyll analysis on leaves and determine the part of leaflets which have the highest chlorophyll content. Analysis of chlorophyll content was carried out by a solvent extraction method in which the absorbance was read in a UV-Vis spectrophotometer. The content of chlorophyll a in leaves varies with each part of the leaves of the coconut plant. Chlorophyll a content in the middle position of coconut leaf child (763.19 µmol / m2) and chlorophyll b content (196.22 µmol / m2). The content of chlorophyll a and b in each part of the leaf child and the right and left positions of the leaves have relatively the same value.Keywords: Coconut, Chlorophyll a, Chlorophyll b

Sign in / Sign up

Export Citation Format

Share Document