In many areas, over half of all diverted water is used for irrigation. Tree fruit crops use a lot of water, but water productivity can be increased using properly-timed precision water stress. In addition to water conservation, increases in water productivity arise from better fruit quality, increased storage life and reductions in pruning and maintenance. One major hurdle to applying precision water stress in orchards is the lack of a reliable, automated method of determining tree water status. However, the influence of physiological characteristics such as rootstock vigor on water productivity are also important. Selecting the most appropriate rootstocks and accurately determining the water status of orchard trees can increase water productivity. Research has shown that some rootstocks can more effectively extract water from soil. In this research, the response to water stress of three different Gisela tart cherry dwarfing rootstocks was compared using a weighing lysimeter system. Gisela 12 and Gisela 3 rootstocks recovered from drought stress more quickly and had higher trunk diameter growth rates than drought-stressed Gisela 5 rootstocks. Two potential methods of determining tree water status were also evaluated. Trunk hydration was measured using electromagnetic sensors and canopy temperature changes were detected using infrared radiometry. Electromagnetic techniques, including time domain reflectometry, can be used to determine the water content of wood. Until recently, the cost of this technology has inhibited its widespread use, but new affordable commercial electromagnetic soil moisture sensors have created renewed interest in this technique. In this research five different types of electromagnetic soil moisture sensors were inserted into the trunks of fruit trees and were monitored over two growing seasons. Maximizing exposure of waveguides to the sapwood increased the response of these sensors to changes in stem water potential. Infrared measurements of canopy temperature have successfully been used with field crops. However, the heterogeneity of orchard canopies makes this technique more difficult in orchards. Here, the efficacy of aiming radiometers at single trees versus at entire orchards was compared over multiple growing seasons. Neither single tree measurements nor whole orchard techniques produced a sufficiently robust signal to recommend them for general use.

Orientador: João Manuel Marques Cordeiro / Abstract: The energetical and environmental problematic related to the cement production is a very sensitive issue. As every other field, the construction industry must go through drastic change in the design of concrete and cement-based materials. The understanding of the physical and chemical properties of the Portland cement (PC) clinker is important to improve its design. Tricalcium silicate C3S, or alite, is the main phase of PC clinker and has been largely studied since it is the first responsible for the strength development of the cement paste. On the other hand, the development of computational methods at the molecular scale has made possible the modelling of structural, dynamical and energetic properties, sometimes hardly measurable by experimental means. Such methods are relatively new in the field of cement chemistry, but have been increasingly employed over the last 15 years. In this project, density functional theory (DFT), classical molecular dynamics (MD), and ab initio molecular dynamics (AIMD) are employed towards a better understanding of mechanical, thermal, and superficial properties of monoclinic C3S, as well as C3S/water interface features. The present thesis consists of five chapters. The first chapter presents a review of the literature on the chemistry of cement, and more particularly on the hydration process modeling. The various phases which compose the Portland cement clinker are introduced, then the the different polymorphs of C3S are described, in particu... (Complete abstract click electronic access below) / Resumo: A produção de cimento envolve questões energéticas e ambientais muito relevantes. Em função disso, a indústria da construção deve sofrer mudanças radicais na concepção de concreto de materiais cimentícios. A compreensão das propriedades físicas e químicas do clínquer de cimento Portland (PC) é importante para melhorar seu design. O silicato tricálcico (C3S), ou alita, é a fase principal do clínquer de PC e tem sido amplamente estudado uma vez que é o principal responsável pelo desenvolvimento da resistência da pasta de cimento. Por outro lado, o desenvolvimento de métodos de cálculo na escala molecular possibilitou a modelagem de propriedades estruturais, dinâmicas e energéticas, às vezes difícil de medir por meios experimentais. Esses métodos são relativamente novos no campo da química do cimento, mas tem sido cada vez mais empregados nos últimos 15 anos anos. Neste trabalho, a teoria de funcional da densidade (DFT), a dinâmica molecular clássica (MD) e a dinâmica molecular ab initio (AIMD) são utilizadas para permitir uma melhor compreensão das características mecânicas, térmicas e de superfície do C3S monoclinico, bem como propriedades da interface C3S/água. Esta tese consiste em cinco capítulos: O primeiro capítulo apresenta uma revisão da literatura sobre a química dos cimento e, mais particularmente, sobre o processo de hidratação e sua modelagem. Introduzimos as diferentes fases que compõem o clínquer de cimento Portland, em seguida, a estrutura e os diferentes polimor... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

Cílem této práce bylo užití termické analýzy, především teplotně modulované diferenční kompenzační kalorimetrie (TMDSC) k odhalení změn ve struktuře huminových kyselin (HA), způsobených pravidelným vlhčením HA vodou a jejím opakovaným sušením. Celkový počet cyklů vlhčení byl pět, neboť následující cykly již nezpůsobily žádné další pozorovatelné strukturální změny. Experimenty provedené v této práci ukázaly, že voda hraje roli nejen v bobtnání struktury HA a přerušení van der Waalsových sil, ale i v přerušení některých vodíkových vazeb, což má větší vliv na snížení teploty skelného přechodu, Tg. Změny v teplotách skelného přechodu byly nepatrné, protože voda ovlivnila především okolí amorfních domén (zodpovědných za skelný přechod), než domény samotné. Dalším úkolem bylo ozřejmit roli volných lipidů ve stabilitě fyzikální struktury HA s ohledem na opakované vlhčení a sušení. Voda periodicky stabilizovala a destabilizovala strukturu HA, ve vzorku HA bez volných lipidů byl vliv vody krátkodobý, voda potřebovala méně času k vyvolání změn ve vzorku, zatímco v původním vzorku byly změny kontinuální. Opakované vlhčení vyvolalo pokles v teplotách fázových přeměn v každém cyklu v porovnání s předcházejícím a ovlivnilo především kinetické procesy, jmenovitě krystalizaci/krystalickou reorganizaci. Opakované vlhčení dále způsobovalo redistribuci a vymytí hydrofilních molekul a tím postupnou hydrofobizaci celé struktury.

Background: Niacinamide (NIA) is one of the most commonly used cosmetic ingredients. It belongs to the vitamin-B3 family and has extensive dermatological therapeutic benefits. NIA has been proven to be a useful skincare product in serving as anti-acne agent, preventing skin hyperpigmentation, removal of wrinkles from the face etc.  Aim: To investigate permeability patterns of NIA, its effect on electrical impedance of the skin membrane and the role it plays in maintaining the hydration of stratum corneum (SC). For this, permeation, chromatography, sorption isotherm and X-ray studies were performed. Results: NIA permeation was observed to correlate with pH and it permeated more when delivered in PBS at pH 7.4 as compared to its permeation in citrate buffer at pH 5. Moreover, skin resistance also increased by Ca. 47% in relation to NIA permeation at pH-5 while it decreased by an average of 45% at pH 7.4. In addition, vapor sorption analysis showed that NIA increased the hydration of SC at 95%RH as compared to buffer controls. This was also supported by X-ray data where NIA treated SC samples were shown to have larger interchain spacing in their keratin filaments in comparison to SC in buffer controls. This increase is usually associated with an increase in the water content of SC and thus NIA might have similar beneficial effects as water and can even be more advantageous as it doesn’t evaporate in dehydrated states unlike water. Moreover, artificial skin model has also been tested in parallel, and it was significantly more permeable to NIA than the human skin. Hence some modifications are necessary before it can be used to replace human/porcine skin. Conclusion: The study showed that pH influences NIA permeation and resistance of skin membrane. Additionally, NIA play beneficial roles by increasing water content of SC at high relative humidity (RH%).

Background: Prostate cancer is the most prevalent form of cancer affecting men.In case of biochemical recurrence, positron emission tomography (PET) targeting prostate-specific membrane antigen (PSMA) on prostate tumor cells is primarily used, in combination with computed tomography (CT), for detection and localization of recurrence. Research for optimizing a PSMA-ligand with high affinity for tumor cells and minimal excretion to the urinary bladder is constantly ongoing, in order to allow better evaluation of the prostate and nearby regions. One such ligand is 18F-PSMA-1007, which was expected to be excreted in the urinary bladder at a rate of 5-10%. However, after switching from diagnostic to low-dose CT, the elimination of 18F-PSMA-1007 in the bladder was higher than expected. Purpose: To evaluate whether hydration during the accumulation period could affect the activity concentration in the bladder. Materials and Methods: The study involved analyzing PET-CT scans obtained from two prostate cancer patient groups who underwent 18F-PSMA-1007-PET with low-dose CT. The groups consisted of 20 participants each, with one group hydrating during the tracer’s accumulation time, while scans from the comparison group were obtained from a time point where patients did not receive instructions about water intake. The amount of radioactivity was measured by placing a standardized 3.00 cm Volume of Interest (VOI) on the bladder, which was then adjusted based on the individual size and shape of the patients' bladder. From the VOI, a standardized uptake value (SUV) was determined, which can be represented as either SUVmean or SUVmax. These values represent the average tracer concentration within a VOI and the highest concentration of the tracer in the urinary bladder, respectively. Results: SUV in the urinary bladder was lower for the hydrated group, where the SUVmean was 1,55 vs 4,5 (p=0,011) for the non-hydrated group. Similar values were obtained for SUVmax, 2,3 vs 6,65 (p< 0,003). Conclusion: This retrospective study suggests that water intake during the accumulation period leads to significantly lower activity concentration in the bladder among these patients, which benefits the detection of recurrences in adjacent areas.

No description available.

Primary Sjögren's Syndrome (SS) is an autoimmune disease that causes dehydration of the eyes, mouth, and throat. Individuals with Primary SS are at risk for voice problems associated with vocal fold dehydration. Topical hydration treatments show promise in reducing the negative effects of vocal fold dehydration on voice production. However, no studies have examined the preventive effects of topical hydration treatments on voice production in individuals at risk for vocal fold dehydration. The purpose of this study was to quantify the effects of a topical vocal fold hydration treatment on voice production in individuals with Primary SS using the Cepstral Spectral Index of Dysphonia (CSID). Eight participants with Primary SS completed an eight-week study involving twice-daily audio recordings of sustained vowels and the Rainbow Passage. Participants received 9 mL of nebulized isotonic saline (0.9% Na+Cl-) immediately following morning and evening voice recordings during weeks 3, 4, 7, and 8 using an ABAB within-subjects experimental design. Baseline CSID values were in the mild range. Although CSID values decreased (improved) during the treatment phases of the study, no statistically significant changes were observed from baseline to treatment. Statistically significant correlations were observed among CSID values and patient-based ratings of vocal effort and dryness, which did improve with treatment (p < .05). These results indicate that topical saline treatments may prevent and treat some voice problems associated with vocal fold dehydration in at-risk populations.

The purpose of this study was to examine the effectiveness of relative fundamental frequency (RFF) in quantifying voice disorder severity and possible change with treatment in individuals with Primary Sjögren's Syndrome (SS). Participants completed twice-daily audio recordings during an ABAB within-subjects experimental study investigating the effects of nebulized saline on voice production in this population. Voice samples of the Rainbow Passage from seven of the eight individuals with Primary SS involved in a larger investigation met inclusion criteria for analysis, for a total of 555 tokens. The results indicated that RFF values for this sample were similar to previously reported RFF values for individuals with voice disorders. RFF values improved with nebulized saline treatment but did not fall within the normal range for typical speakers. These findings were similar to other populations of voice disorders who experienced improvement, but not complete normalization, of RFF with treatment. Patient-based factors, such as age and diagnosis as well as measurement and methodological factors, might affect RFF values. The results from this study indicate that RFF is a potentially useful measure in quantifying voice production and disorder severity in individuals with Primary SS.

No description available.

The purpose of this study was to determine the effect of stratum corneum (SC) hydration by distilled water on SC ion content and sweat ion concentrations as measured by occlusive sweat patch. 10 men and 10 women completed approximately 40 minutes of moderate exercise in the heat. Select skin sites were hydrated before sweating by adhering cylinders of distilled water to forearm skin. SC samples were taken before and after exercise using the tape stripping (TS) method and sweat samples were taken with homemade filter paper sweat patches with a tegaderm backing. An increase in SC hydration was verified by a reduction in SC potassium concentration (p<0.05). SC hydration caused a significant decrease in sweat potassium (K+), calcium (Ca++), and lactate (Lac-) concentration: K+ =8.14 ± 0.46 to 6.56 ± 0.46, Ca++ = 0.86 ± 0.17 to 0.67 ± 0.18, Lac- = 11.64 ± 1.36 to 8.82 ± 1.11, euhydrated to hyperhydrated respectively(p<0.05). SC sodium (Na+) and K+ concentration increased after sweating without a sweat patch (p<0.05). Our data do not dispute the idea that electrolytes can be leached from the SC by distilled water or sweat trapped within an occlusive dressing. However, our data indicate that during normal sweating the SC "dehydrates" resulting in an increase in the electrolyte concentration. As such, we propose that the occlusive dressing does trap sweat on the skin but the important end result is that it prevents water movement out of the SC and thereby producing a more concentrated sweat.