Search results for "elements"
showing 10 items of 799 documents
Patterns and rates of nucleotide substitution, insertion and deletion in the endosymbiont of antsBlochmannia floridanus
2009
Genome reduction is a general process that has been studied in numerous symbiotic bacteria associated with insects. We investigated the last stages of genome degradation in Blochmannia floridanus, a mutualistic bacterial endosymbiont of the ant Camponotus floridanus. We determined the tempo (rates of insertion and deletion) and mode (size and number of insertion-deletion events) of the process in the last 200,000 years by analysing a total of 16 intergenic regions in several strains of this endosymbiont from different ant populations. We provide the first calculation of the reduction rate for noncoding DNA in this endosymbiont (2.2 x 10(-8) lost nucleotides/site/year) and compare it with th…
The determination of trace element concentrations in fly ash samples using ultrasound-assisted digestion followed with inductively coupled plasma opt…
2009
A method of ultrasound-assisted digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) used for the determination of trace element (chromium, copper, lead, nickel, vanadium and zinc) concentrations in fly ash samples was developed. All the measurements were performed in robust plasma conditions. Ultrasound-assisted digestion procedures using digestion solutions of aqua regia and hydrofluoric acid (HF) resulted in recovery rates of over 80% for all the analyte elements. Ultrasound-assisted two-step digestion with digestion solutions of 6 mL of HNO₃(Step 1) and 3 mL of HNO₃+ 3 mL of HF (Step 2) resulted in recovery rates of over 92% for all the analyte elemen…
Current Acquaintance on Agronomic Biofortification to Modulate the Yield and Functional Value of Vegetable Crops: A Review
2023
Fresh vegetables and fruits have always been the mainstays of good nutrition as providers of fiber, beneficial phytochemicals (such as vitamins and phenolic compounds), and minerals. Today and in the future, biofortification is a promising strategy to increase the concentration of these compounds. Considering the importance of minerals in human health, the enrichment of fresh produce for consumption has been considered through specific agronomic approaches. This review discusses, in detail, the latest findings on vegetable agronomic biofortification, aimed at increasing the concentration of crucial minerals, such as iron (Fe), zinc (Zn), iodine (I), selenium (Se), molybdenum (Mo), and silic…
Kalcīts un tā veidošanās apstākļi augšējā devona Daugavas svītas dolomītos Latvijas centrālajā un austrumu daļā
2017
Bakalaura darbā “Kalcīts un tā veidošanās apstākļi augšējā devona Daugavas svītas dolomītos Latvijas centrālajā un austrumu daļā” ir raksturotas minerāla kalcīta fizikālās īpašības, mikroelementu saturs un veidošanās apstākļi. Pētījumi veikti 8 dolomīta atradnēs; ģeoloģiskajā griezumā un atradņu teritorijā salīdzinātas kalcīta īpašības. Testētas kalcīta fluorescences izpausmes, pētīti plānslīpējumi, raksturoti kalcītā sastopamie mikroelementi un oglekļa stabilo izotopu attiecības tajā. Secināts, ka kalcīts kristalizējies no atmosfēras ūdeņiem sauszemes apstākļos. Šis minerāls veidojies paleokarsta procesa beigu stadijā pēc iegruvumu izveidošanās. Atslēgas vārdi: mineraloģija, paleokarsts, f…
Active biomonitoring (moss-bags) of volcanic emissions on Mt. Etna
2011
Biomonitoring may be defined as the use of organisms and biomaterials (biomonitors) to obtain information on certain characteristics of a particular medium (atmosphere, hydrosphere etc.). In particular, mosses accumulate large amounts of trace metals, making them good bioaccumulators to estimate atmospheric pollution. The moss-bags technique, introduced in the early 1970’, has become very popular. Such active biomonitoring technique is particularly useful in highly polluted areas and has been extensively used in industrial and/or urban areas to examine deposition patterns and to recognize point sources of pollution. The main objective of this study, which represents the first application of…
Drāmas elementu izmantošana jaunāko pusaudžu motivācijas veicināšanai angļu valodas gramatikas apgūšanā
2020
Šis diplomdarbs sniedz teorētisku pamatojumu un piedāvā praktiskus padomus drāmas tehnikas izmantošanai angļu valodas stundās pamatskolā. Uzsvars tika likts uz gramatikas kompetences attīstību. Pētījuma mērķis bija noskaidrot, vai ir iespējama drāmas elementu izmantošana pamatskolas angļu valodas stundās un noskaidrot vai tā attīsta izglītojamo gramatikas kompetenci. Prakses laikā tika veikta izpēte, izmantojot gadījuma pētījumu, kā galveno pētījumu metodi. Darbā tika izmantotas tādas datu vākšanas metodes kā novērojumi, anketas un gala testa analīze. Rezultāti pierādīja, ka drāmas paņēmienus var piemērot nodarbībām ar jaunākiem pusaudžiem, kuri studē angļu valodu, arī tika parādīts, ka tā …
Indirect chronology method employing rare earth elements to identify Sagunto Castle mortar construction periods
2017
A novel indirect chronology method has been developed to identify Sagunto Castle construction periods. The method is based on the use of inductively coupled plasma mass spectrometry (ICP-MS) to determine rare earth elements (REE) and other trace elements in mortars. Additionally, a no destructive geochemical analysis based on X-ray fluorescence (XRF) was employed for major elements determination. Collected chemical data were processed through Principal Component Analysis (PCA) to highlight any differences among the mortars belonging to different buildings and construction periods. The results show that PCA analysis permits to discriminate construction periods according to mortar sample REE …
Criteri per l’analisi post-danno – Criteria for post-damage analysis.
2010
Gli elementi non-strutturali risultano assai più vulnerabili al sisma delle strutture, così come reso evidente dai terremoti che nell’ultimo decennio hanno colpito il nostro paese. Il danneggiamento di tali elementi, oltre a mettere a serio rischio la sicurezza degli edifici, e dunque l’incolumità, spesso rende diseconomici, disagevoli o addirittura impraticabili gli interventi di riparazione degli edifici. Ciò anche quando questi sono a struttura intelaiata e progettati e realizzati con criteri antisismici e le strutture non hanno subito danni di rilievo. D’altronde il comportamento sismico degli elementi non strutturali è stato lungamente trascurato e dall’analisi dello stato dell’arte in…
Seismic prevention and rahabilitation of nonstructural elements. Criteria to define a post-seismic damage analysis procedure
2012
It reports very briefly the research work, developed by the author during her Doctorate course, about a post-seismic damage analysis procedure for nonstructural elements of framed structure building systems
Le attività all’interno del progetto: il workshop. Gestione del campus universitario di Palermo e dell’Edificio 14 Facoltà di Architettura - The acti…
2010
Verificata la mancanza di attenzione alla prevenzione e riabilitazione sismica degli elementi non strutturali nella ricerca scientifica e nella normativa tecnica italiana, è stato avviato un progetto di cooperazione internazionale tra l’Università di Palermo e l’Università di Berkeley dal titolo “Prevenzione e riabilitazione sismica nonstrutturale.Confronto fra due culture di prevenzione sismica al fine di redigere linee guida per un manuale d’uso degli edifici scolastici”, finanziato nell’ambito del programma CoRI 2005/2006 dell’Ateneo di Palermo. Tra le varie attività previste durante la permanenza del partner straniero a Palermo è stato organizzato un workshop, che ha visto coinvolto un …