Abstract Interactions between the components of papermaking suspensions (e.g. fibres, fillers, fines and polymers) have a remarkable effect on various unit processes in papermaking. The filterability of fibre suspensions, which is a crucial property for example in paper sheet forming and solid recovery, is also known to be depended on particle interactions. However, due to the complex nature of the interactions, the role of these phenomena in fibre suspension filtration is still not fully understood. The focus of this thesis was to find out how phenomena associated to fibre flocculation, fibre deflocculation and filler particle deposition affect the filterability of fibre suspensions in terms of their dewaterability and retention. It was shown that the influence of fibre flocculation on dewatering is closely related to the structure of fibre flocs. More importantly, the internal density of flocs and factors that impacted the packing structure of filter cakes, such as floc size, played a crucial role in fibre suspension dewaterability. Dense flocs with a low internal porosity particularly induces fast water flow by a mechanism termed as the “easiest path mechanism” through the large voids around the flocs. The effect of fibre suspension dispersing on dewaterability and particularly fines retention was found to be associated to the mechanism of action of the deflocculation agent. Carboxymethylcellulose (CMC), the deflocculant used in this study, had detrimental effects on the dewatering of a pulp suspension both when being adsorbed on fibre surfaces and when remained in the liquid phase. However, adsorbed CMC causes more plugging of the filter cake because it disperses the fines more profoundly. Thus the adsorbed CMC also reduces fines retention considerably more than CMC did in the liquid phase. Filler deposition and retention was found to be significantly higher on pulp fines fractions of mechanical and chemical pulp than on fibre fractions due to the higher external surface area of fines. The surface charge densities of pulp fractions also affected their ability to adsorb fillers. Cationic charges of filler particles was in turn observed to induce deposition of fillers on fibre surfaces which increased retention but also the dewaterability of a fibre suspension due to a decrease in total surface area of a suspension.

Silicon carbide is a useful monolithic and matrix ceramic due to its excellent mechanical properties and corrosion/oxidation resistance at high temperature. This makes it an attractive material for use in advanced applications, such as aircraft engines and high-speed flight. In this study, additively manufactured monolithic SiC and Cf/SiC CMCs, processed via direct ink writing (DIW) of a 53 vol% colloidal suspension, achieved >96% theoretical density through pressureless sintering. When present, fibers are aligned in the direction of the print path. Five different print paths were studied, including a 0o path, 90o path, 0/90o path, 0/15/30/45/60/75/90o path, and 0/30/60/90/60/30/0o path. Four-point bend testing was performed to determine flexural strength and Weibull analysis was performed. Strengths were highest for the 0o print path. The characteristic strength, σo, of this print path was 375 MPa with a Weibull modulus of 7.4 for monolithic SiC and a σo of 361 MPa with a Weibull modulus of 10.7 for Cf/SiC. Weibull modulus was greater for Cf/SiC samples compared to identically printed monolithic SiC samples. SEM and optical microscopy were used to analyze printed parts which showed a high degree of fiber alignment in the direction of the print. Fiber pullout was observed on the fracture surface, as well as intragranular fracture.

This study aimed to investigate EFL teachers’ perspectives on distance education in the Swedish context. The ongoing Covid-19 pandemic has fuelled the need to investigate teachers’ experiences in the transition from face-to-face to online teaching. Five EFL teachers were interviewed to collect qualitative data, which was analysed using thematic analysis. The findings show that the participants had both positive and negative experiences of distance education. Their overall experience has shown that there have been affordances and limitations of distance education. The affordances of distance education, according to the participants, are that: (1) it enabled the teachers to focus more on students as individuals, (2) it made recording the lessons easier, which has made the participants’ work more manageable, and (3) it increased the quality of private conversations with individual students. The results also showed that according to the participating teachers, social interaction with the students and assessment practices were negatively affected by distance education. Overall, the participants’ experience of teaching trough distance education has been challenging. However, integrating technology in their lessons has enabled creative planning.

This study examined the uses of computer-mediated communication (CMC) by educators in selected public schools. It used Rogers' Diffusion of Innovation Theory as the underpinnings of the study. CMC refers to any exchange of information that involves the use of computers for communication between individuals or individuals and a machine. This study was an exploration of difficulties users confront, what services they access, and the tasks they accomplish when using CMC. It investigated the factors that affect the use of CMC. The sample population was drawn from registered users on TENET, the Texas Education Network as of December 1997. The educators were described with frequency and percentages analyzing the demographic data. For the research, eight indices were selected to test how strongly these user and environmental attributes were associated with the use of CMC. These variables were (1) education, (2) position, (3) place of employment, (4) geographic location, (5) district size, (6) organization vitality, (7) adopter resources, and (8) instrumentality Two dependent variables were used to test for usage: (1) depth or frequency of CMC usage and amount of time spent online and (2) breadth or variety of Internet utilities used. Additionally, the users' perception of network benefits was measured. Network benefits were correlated with social interaction and perception of CMC to investigate what tasks educators were accomplishing with CMC. Correlations, SEQ CHAPTER h r 1 crosstabulations, and ANOVAs were used to analysis the data for testing the four hypotheses. The major findings of the study, based on the hypotheses tested, were that the socioeconomic variables of education and position influenced the use of CMC. A significant finding is that teachers used e-mail and for Internet resources less frequently than those in other positions. An interesting finding was that frequency of use was more significant for usage than amount of time spent online. This implied that an accessible computer and network connection was more important than the amount of time available to use it. There was little evidence that place of employment, geographic location, or school district size influenced differences in use or nonuse of CMC features. Significant findings for Organization Vitality suggest that a school could contribute to usage by educators when computers and network connections that were close, convenient, and accessible. The Individual Resources of importance for usage were years of experience and confidence with computers and Internet usage. The heavy uses of CMC for communication attested to the importance of CMC in reducing practitioner isolation for many educators. Communication, professional development, work productivity, and professional information seeking showed significant relationships with network benefits and perceived CMC attributes. CMC is a pervasive communication technology that continues to expand in all areas of society. For educators and education it is a venue promising great rewards.

The thesis on „Utilization of potassium polyaspartate to ensure wines crystal stability“ is divided in two section, as theoretical so practical part. Theoretic part examined general colloid definition and division of disperse systems. This part further described various kind of turbidities in connection to the wine itself. It comprising detailed turbidity description together with methods and prevention option through the most commonly used stabilizers (e.g. carboxymethylcellulose, metatartaric acid, gum arabic etc.). Experimental, is theoretical parts dealt with the experiment execution itself. The experiment focused on already known and in practice used preparations and their comparison with new potassium polyaspartate-based preparation. Stabilisers were added in different concentration, variants and combinations in non-stable wine. The wines were immediately botteled in with proper preparations and stored in two variants (cellar and indoor temperature). The parameters such as wine color variation and crystal turbidity formation were examined throughout the entire storage period for each option separately. From each variant were eastablished three equal bottles in order to verify potential opening and time-dependent differeneces of already used preparations. The wines were subjected various methods of evaluation (visual check, gravimetry, evaluation at Alpha machine, pH, turbidity) and the results were statistically evaluated and processed. In the end was the follow-up reseach recommended with the same subject of focus.

Since 1990, the usage of emojis has increased and become a part of our everyday communication.The ambiguous nature of emojis has been shown by multiple previous studiesbut there is a qualitative gap in research of what the meaning of these emojis are. On thesocial media app TikTok emojis, in combination with written text, are used by users of theapp to communicate with each other, and the content creators, via the comment sectionof videos. This study researches in which laughable context specific emojis, representinglaughter, appeared. Laughter has always been a part of human communication and was previously referredto as being a way of showing agreement. Laughter was a way to give a preferred answer toa humorous situation. Later research has expanded this claim to other dimensions wherelaughter is not only a response to humor, but also a way of making dispreferred answersagreeable. Laughter is a way of affiliation and is a quick way to establish a relationshipwith another person. This study collected thirteen examples from the comment section on the digital app,TikTok. All examples were related to laughter and contained at least one emoji. To beselected as an example, the original comment also needed a direct response. All exampleswere analysed with multimodal interaction analysis. When preforming the analysis, thefocus was recipient design, preference, common ground and affiliation. In line with previous studies, the results confirm the ambiguous nature of emojis butalso that laughter can be represented in many different ways. One meaning found wasgenuine, hysterical laughter which was represented by both face with tears of joy emojiand rolling on the floor laughing emoji. Another meaning found was the embarrassinglaughter context where the comment creator is looking for someone to relate to the loudlycrying emoji and the grinning face with tear of sweat emoji were present. The skull emojiwas used in context where the laughter was some what hysterical and the context wasfunny, but there was serious truth behind the laugh. The amount of emojis used makes adifference in meaning but also how the text that the emojis are related to in the comment isexpressed. This study contributes to the field of internet linguistics and conversation analysis andcould hopefully give more insight to the digital communication of today.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED, APS-I) is exceptionally common in Finland. Most patients have chronic oral candidiasis since childhood. Thus, most patients receive repeated courses of antifungals throughout their life. Eleven of our patients (31.4%) have become colonized with Candida albicans with decreased sensitivity to fluconazole. A total of 43 isolates of C. albicans from 23 APECED patients isolated during the years 1994 to 2004 were divided into 2 groups: fluconazole-susceptible dose-dependent (MIC, 16-32 μg/mL, 18 isolates) and fluconazole-susceptible (MIC ≤8 μg/mL, 25 isolates) groups. Antifungal activity of amphotericin B, echinocandins, and azoles was determined by the Clinical and Laboratory Standards Institute M27-A2 methodology. All isolates were highly susceptible to amphotericin B and echinocandins. Posaconazole and voriconazole were active against all isolates. Our data suggest that topical amphotericin B could continue to be a safe and active drug for daily administration for APECED patients. Posaconazole, voriconazole, and echinocandins may be useful in some complicated cases.

Tato práce je zaměřena na agregační chování nativního a hydrofobně modifikovaného hyaluronanu, v různých molekulových hmotnostech a stupních substituce, ve vodném prostředí. Pro studium bylo vybráno šest fluorescenčních sond s různými vlastnostmi (Pyren; Nilská červeň; Perylen; Akridinová oranž; 6-(p-Toluidino)-2-nafthalenesulfonová kyselina; PRODAN). a výsledky získané pomocí těchto sond byly porovnány s jednoduchým anionaktivním tenzidem (Dodecylsíran sodný). U všech použité sond byly testovány jejich spektrální vlastnosti v závislosti na polaritě okolí a/nebo na koncentraci. Pro stanovení vlastností nepolárního jádra hyaluronového agregátu byly vybrány dvě sondy (Pyren, Nilská červeň). U domén byly sledovány polarita a viskozita vnitřního prostředí a jejich závislost na iontové síle a teplotě. Pro modifikované hyaluronany bylo stanoveno, že jejich kritická agregační koncentrace klesá s rostoucí molekulovou hmotností a stupněm substituce. Pro vlastní doménu platí, že její kompaktnost roste s rostoucí iontovou silou, ale klesá s rostoucí teplotou.

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