Quantifying the Threshold for Fragmentation of Newtonian and Non-Newtonian Drops

This dissertation investigates how the properties of liquid drops influence the minimum aerodynamic forces needed to cause the drop to fragment (breakup). For this work, we focus only on aerodynamic forces that are applied on a stationary drop by a sudden, uniform flow, a process called impulsive acceleration. Previous studies have largely focused on the fragmentation of spherical drops of Newtonian fluids (liquids with constant viscosity, like water), when impulsively accelerated in air-like ambient medium. Such systems only capture a limited range of drop and ambient properties (described by non-dimensional groups). Many real-world applications, such as aerial fire retardant delivery, involve conditions beyond this typical range. Fire retardants, for instance, can exhibit shear-thinning behavior (their viscosity decreases under stress), and the drops undergoing fragmentation often start with a non-spherical shape. The ambient medium could also be one with much higher densities and viscosities, common in cases where liquid drops fragment in other liquids. Through this dissertation, we aim to utilize computational models, specifically interface-tracking multiphase flow direct numerical simulations (DNS), to systematically examine how various drop properties affect the threshold of secondary fragmentation. The research is divided into five main parts. First, a model was developed to predict the trajectory and coverage of aerially delivered fire retardants, motivating the need for a deeper understanding of drop fragmentation. Second, we expanded the study of spherical, Newtonian drops beyond existing parameters, identifying a more robust non-dimensional parameter to predict the breakup threshold. Third, we performed the first systematic investigation of how initial drop shape affects fragmentation, quantifying its significant influence. Fourth and Fifth, we characterized the influence of shear-thinning or a viscoplastic nature of the drop fluid

Stomatal Conductance Depends on Abscisic Acid Production in Both Guard Cells and in Phloem Companion Cells

The question how plants use water is important as water availability is often a limiting factor for plant growth. Stomata are mainly responsible for water loss from plant tissues and, therefore, regulatory mechanisms controlling stomatal apertures are in the research focus of plant water management. Abscisic acid (ABA) has an important role in reducing stomatal conductance, however, importance of ABA biosynthesis in guard cells and in phloem is not fully studied. To address this question, we generated transgenic plants with restored ABA biosynthesis either in guard cells or in phloem by using tissue-specific promoters. Our study shows that both guard cells and phloem companion cells can produce ABA in quantities which are enough to regulate plant development and stomatal conductance on the level of wildtype plants

Areas of Research Management and Administration in Austria

Abstract Austria has not yet established a single national organisation for research management and administration (RMA). Various research related institutions are organised in individual professional networks within their categories of organisational structure – public, private, and industry. Hence, the creation of a joint RMA association is a good aim to target in the near future. The obvious need of a strong networked community of RMAs across disciplines and organisational structures, especially in a setting of a growing global research arena, shall exemplify the development of such an Association of Research Managers and Administrators-Austria (ARMA-T). Furthermore, external factors play an increasingly important role in research development and RMAs. It depends on how their home organisations – universities, industry, and intermediaries – will understand the need for cooperation, platform building, and continuous development and professionalisation. Vision and foresight from several constituents and stakeholders will have to play a starring role as well as supporting the whole community. On top of it, international knowledge exchange helps to create those necessary conversations and networks for such a development.Abstract Austria has not yet established a single national organisation for research management and administration (RMA). Various research related institutions are organised in individual professional networks within their categories of organisational structure – public, private, and industry. Hence, the creation of a joint RMA association is a good aim to target in the near future. The obvious need of a strong networked community of RMAs across disciplines and organisational structures, especially in a setting of a growing global research arena, shall exemplify the development of such an Association of Research Managers and Administrators-Austria (ARMA-T). Furthermore, external factors play an increasingly important role in research development and RMAs. It depends on how their home organisations – universities, industry, and intermediaries – will understand the need for cooperation, platform building, and continuous development and professionalisation. Vision and foresight from several constituents and stakeholders will have to play a starring role as well as supporting the whole community. On top of it, international knowledge exchange helps to create those necessary conversations and networks for such a development

PENGGUNAAN LAGU WAJIB NASIONAL SEBAGAI MEDIA PEMBELAJARAN PKn UNTUK MENINGKATKAN KESADARAN BERBANGSA DAN BENEGARA (Studi Deskriptif di Kelas VII SMPN 1 Pancatengah)

Sekolah sebagai lembaga pendidikan memiliki peran penting dalam peningkatan kesadaran berbangsa dan bernegara. Pengintegrasian pendidikan dengan kesadaran berbangsa dan bernegara bisa dilakukan melalui media pembelajaran lagu wajib nasional. Penelitian bertujuan untuk mengetahui penggunaan, dampak, hambatan serta upaya-upaya mengatasi masalah atas penerapan lagu wajib nasional sebagai media pembelajaran PKn untuk meningkatkan kesadaran berbangsa dan bernegara di kelas VII SMP N I Pancatengah Tasikmalaya. Penelitian ini menggunakan pendekatan kualitatif yang bersifat deskriptif. Teknik pengumpulan data yang digunakan dalam penelitian ini menggunakan beberapa cara, yakni observasi, wawancara, wawancara dan catatan lapangan. Penggunaan lagu wajib nasional sebagai media pembelajaran PKn untuk meningkatkan kesadaran berbangsa dan bernegara pada kelas VII SMP N I Pancatengah Tasikmalaya digunakan sebanyak empat kali pertemuan dengan cara menunjuk salah satu siswa untuk memimpin menyanyikan lagu wajib nasional, menuliskan dan menjelaskan makna lirik lagu tersebut, pembentukan kelompok diskusi untuk membahas makna lirik lagu wajib nasional serta pemberian pemberian tugas yang berkaitan dengan makna lirik lagu wajib nasional. Lagu wajib nasional sebagai media pembelajaran memiliki dampak positif terhadap peningkatan sikap yang ditunjukkan oleh siswa kelas VII, yakni: taat aturan, Gotong royong dan saling menghargai. Kendala yang dihadapi dalam penggunaan lagu wajib nasional tersebut adalah pemahaman siswa terhadap makna lirik lagu yang masih kurang, sarana yang masih minim, perasaan malu siswa saat menyanyikan lagu wajib nasional. Adapun upaya untuk mengatasi kendala tersebut adalah dengan cara: pemberian tugas, pembentukan kelompok diskusi dan pengadaan sarana pendukung.;--- Schools as educational institutions have an important role in raising awareness of nation and state. The integration of education with national and state awareness can be done through the national mandatory learning media. The study aims to determine the use, impact, obstacles and efforts to overcome the problem of the implementation of national mandatory songs as a medium of learning Civics to raise awareness of nation and state in class VII SMP N I Pancatengah Tasikmalaya. This research uses descriptive qualitative approach. Data collection techniques used in this study using several ways, namely observation, interviews, interviews and field notes. The use of national mandatory songs as a medium for learning Civics to raise awareness of nation and state in class VII N I Pancatengah Tasikmalaya used four times by appointing one of the students to lead the national mandatory song, to write and explain the meaning of the song lyrics, the formation of the discussion group To discuss the meaning of the national mandatory song lyrics as well as giving the assignment related to the meaning of the lyrics of national mandatory song. National compulsory song as a medium of learning has a positive impact on the improvement of attitude shown by the students of class VII, namely: obedient rules, mutual cooperation and mutual respect. Obstacles encountered in the use of national mandatory songs is the students' understanding of the meaning of song lyrics that are still lacking, the means are still minimal, the embarrassment of students when singing national mandatory song. The effort to overcome these obstacles is by: the assignment of tasks, the formation of discussion groups and the procurement of supporting facilities

Nahaalune õhkemfüseem, pneumomediastiinum ja pneumotooraks laparoskoopilise kubemesonga operatsiooni tüsistusena

Laparoskoopiline kubemesonga operatsioon (täielik ekstraperitoneaalne plastika, TEP) on viimasel ajal järjest enam juurdunud ning aktsepteeritud operatsioonimeetod kubemesonga ravis. Retsidiivide esinemissagedus pärast laparoskoopilist operatsiooni on ca 1%, avatud operatsiooni korral 0,6–1,4% (1, 2). Teatud tüsistused on võimalikud mõlema meetodi korral, kuid tüsistuste üldine määr on mõlema operatsioonimeetodi korral sarnane. Pneumomediastiinum, pneumotooraks ja nahaalune õhkemfüseem on laparoskoopilise operatsiooni järel üliharvad tüsistused (6). &nbsp

Nikotiinisõltuvuse määramise epidemioloogilised ja geneetilised võimalused: Eesti arstide suitsetamisuuring 2014

http://www.ester.ee/record=b469046

Frequencies of mtDNA haplogroups in Southeastern Europe: Croatians, Bosnians and Herzegovinianas, Serbians, Macedonians and Macedonian Romani

Mitochondrial DNA polymorphisms were analyzed in of 1,610 randomly chosen adult men from 11 different regions from southeastern Europe (Croatians, Bosnians and Herzegovinians, Serbians, Macedonians and Macedonian Romani). MtDNA HVS-I region together with RFLP sites diagnostic for main Euroasian and African mtDNA haplogroups were typed to determine haplogroup frequency distribution. The most frequent haplogroup in studied populations was H with the exception of Macedonian Romani among whom the most frequent were South Asian (Indian) specific variants of haplogroup M. The multidimensional scaling plot showed two clusters of populations and two outliers (Macedonian Romani and the most distant from mainland Croatian island of Korčula). The first cluster was formed by populations from three Croatian islands (Hvar, Krk and Brač) and the second cluster was formed by Macedonians, Serbians, Croatians from mainland and coast, Herzegovinians, Bosnians, Slovenians, Poles and Russians. The present analysis does not address a precise evaluation of phylogenetic relations of studied populations although some conclusions about historical migrations could be noticed. More extended conclusions will be possible after deeper phylogenetic and statistical analyses

Aktsiaseltsi juhtimisorganite mudelid ja nende rakendamine Eesti õiguses

http://www.ester.ee/record=b4409240~S1*es

Mining Duplicate Questions of Stack Overflow

There has a been a significant rise in the use of Community Question Answering sites (CQAs) over the last decade owing primarily to their ability to leverage the wisdom of the crowd. Duplicate questions have a crippling effect on the quality of these sites. Tackling duplicate questions is therefore an important step towards improving quality of CQAs. In this regard, we propose two neural network based architectures for duplicate question detection on Stack Overflow. We also propose explicitly modeling the code present in questions to achieve results that surpass the state of the art

On the Threshold of Drop Fragmentation under Impulsive Acceleration

We examine the complete landscape of parameters which affect secondary breakup of a Newtonian droplet under impulsive acceleration. A Buckingham-Pi analysis reveals that the critical Weber number $\mathit{We}_\mathit{cr}$ for a non-vibrational breakup depends on the density ratio $(\rho)$, the drop $(\mathit{Oh}_d)$ and the ambient $(\mathit{Oh}_o)$ Ohnesorge numbers. Volume of fluid (VOF) multiphase flow simulations are performed using Basilisk to conduct a reasonably complete parametric sweep of the non-dimensional parameters involved. It is found that, contrary to current consensus, even for $\mathit{Oh}_d \leq 0.1$, a decrease in $\mathit{Oh}_d$ has a substantial impact on the breakup morphology, motivating plume formation. In addition to $\rho$, $\mathit{Oh}_o$ also affects the balance between pressure differences between a droplet's pole and its periphery, and the shear stresses on its upstream surface, which ultimately dictates the flow inside the droplet. This behavior manifests in simulations through the observed pancake shapes and ultimately the breakup morphology (forward or backward bag). All these factors affecting droplet deformation process are specified and theories explaining the observed results are provided. A $\mathit{We}_\mathit{cr}-\mathit{Oh}_d$ plot is provided to summarize all variations in $\mathit{We}_\mathit{cr}$ observed due to changes in the involved non-dimensional parameters. All observed critical pancake and breakup morphologies are summarized using a phase diagram illustrating all deformation paths a droplet might take under impulsive acceleration. Finally, based on the understanding of process of bag breakup gained from this work, a non-dimensional parameter to predict droplet breakup threshold is derived and tested on all simulation data obtained from this work and all experimental data gathered from existing literature