Ethylene-independent promotion of photomorphogenesis in the dark by cytokinin requires COP1 and the CDD complex

The transition of skotomorphogenesis to photomorphogenesis is induced by the perception of light, and is characterized by the inhibition of hypocotyl elongation and opening of cotyledons. Although it is known that the plant hormone cytokinin inhibits hypocotyl elongation in dark-grown Arabidopsis plants when applied in high concentrations, it is unclear to what extent this response is the result of cytokinin alone or cytokinin-induced ethylene production. Here, we show that cytokinin-induced inhibition of hypocotyl elongation is largely independent of ethylene and suggest a close connection between the cytokinin two-component system and the light-signaling networks. We show that this cytokinin signal is mainly mediated through the cytokinin receptor ARABIDOPSIS HISTIDINE KINASE3 and the ARABIDOPSIS RESPONSE REGULATOR1 in combination with ARR12. Interestingly, mutation of CONSTITUTIVELY PHOTOMORPOGENIC1 (COP1), DE-ETIOLATED1, and CYTOKININ INSENSITIVE4/COP10 renders plants insensitive to cytokinin, and these factors are indispensable for the transcriptional response during cytokinin-induced de-etiolation, indicating that a functional light-signaling pathway is essential for this cytokinin response. In addition, the effect of cytokinin on hypocotyl elongation is strongly dependent on the light conditions, with higher light intensities causing a switch in the response to cytokinin from an inhibitor to a promoter of hypocotyl elongation

Adverse Effects of Metals on the Alveolar Part of the Lung

Rabbits were exposed to low levels of metal dust or metal ions by inhalation for 1-8 months, 5 days/week and 6h/day. Following exposure lung tissue was examined by light and electron microscopy, the lung content of phospholipid was analyzed and the morphology and function of alveolar macrophages were investigated. Metallic nickel dust as well as soluble nickel chloride produced accumulation of macrophages and laminated structures in alveoli and increased volume density of alveolar type II cells. The amount of phospholipids was elevated, mainly due to an increase in disaturated phosphatidylcholine. After one month exposure to metallic nickel dust or soluble nickel chloride, the alveolar macrophages contained surfactant inclusions and were functionally activated. After 3 and 6 months exposure to metallic nickel the macrophages were \u27overfed\u27 and inactive. A similar reaction is seen in the human disease pulmonary alveolar proteinosis. Exposure to cadmium chloride gave a similar reaction pattern as nickel did but in addition interstitial alveolitis. One month exposure to cobalt chloride affected the growth pattern of type II cells which formed nodules projecting into the alveolar lumen. Four months exposure to cobalt chloride resulted in further developed type II cell nodules, areas of hyperreactive type II cells, and interstitial inflammation. Copper chloride produced no effects apart from a slight increase in volume density of type II cells. Hexa- and trivalent chromium mainly affected the alveolar macrophages which showed enlarged lysosomes. Thus, different metal ions, in similar concentrations produced different pathological effects in the lung

Atomic Layer Deposited Catalysts for Fuel Cell Applications

The micro direct methanol fuel cell (µDMFC) has been proposed as a candidate to power portable applications. The device can operate at room temperature on inexpensive, energy-dense methanol fuel, and it can be easily "recharged" by fuel refilling. Microfabrication techniques could be one route for the realization of such tiny devices. It is a mature technology, suitable for mass production, where versatile structuring is available at the micro and nano regime. Carbon black supported catalysts synthesized by wet chemistry methods are not readily applicable for standard microfabrication techniques. Atomic layer deposition (ALD), on the other hand, is a highly suitable and still relatively unexplored approach for the synthesis of noble metal catalysts. It is a vapor phase growth method, primarily used to deposit thin lms. ALD is based on self-limiting chemical reactions of alternately injected precursors on the sample surface. Its unique growth characteristic enables conformal and uniform lms of controlled thickness and composition. In certain conditions ALD commences by island growth, resulting in discrete nanoparticle formation, which is generally preferred for catalytic applications. Pt-Ru is the best catalyst toward the methanol oxidation reaction (MOR). In the work described in this PhD dissertation, two series of Pt-Ru ALD catalysts supported on nitrogen-doped multi-walled carbon nanotubes (N-CNTs) have been evaluated toward the CO oxidation and MOR at room temperature in a three-electrode electrochemical cell. The first series was comprised of Pt-Ru ALD catalysts of various Ru compositions, between 0 and 100 at.%. For the compositions investigated, the best catalyst had a Ru composition of 29 at.%. In the second series Ru-decorated Pt catalysts of various Ru loadings, i.e., various Ru ALD cycles (1, 2, 5, 10 and 20), were investigated. The Pt nanoparticles decorated with 2 Ru ALD cycles exhibited highest catalytic activity, which also outperformed the best catalyst of the first series. In addition, a Si-based fuel cell design with ALD catalysts is presented, and its anode was evaluated toward the MOR

Oral diseases and oral Health related behaviors in adolescents living in Maasai population areas in Tanzania: a cross sectional study

Background: Oral diseases, such as dental caries, tooth wear, dental erosion and periodontal diseases are major health problems in many societies. The study aim was to explore the association between oral health related behaviors and the presence of oral diseases in adolescents living in Maasai population areas in the northern part of Tanzania. Methods: A cross sectional study was conducted in 2016 using one stage cluster sample design. A total of 989 adolescents were invited and 906 (91.6%; (Maasais n = 721, non Maasais n = 185) accepted the invitation and completed an interview and clinical oral examination in a school setting (mean age 13.4 years, SD 1.2, range 12–17 years). Chi-square test, bivariate analysis and logistic regression were performed to analyze data. Results: Logistic regression revealed that: adolescents with low frequency of tooth cleaning (OR = 10.0, CI 4.3–20.0) was associated with poor oral hygiene and that more regular tooth cleaning (OR = 0.1, CI 0.04–0.14) and the use of plastic type of tooth brush (OR = 0.7, CI 0.53–0.99) were associated with less gingival bleeding. High consumption of biscuits (OR = 2.5, CI 1.7–3.8) was associated with presence of dental caries and the use of magadi (OR = 24.2, CI 11.6–50.6) as a food additive was the covariate for more severe dental fluorosis (TF grade 5–9). Regular intake of carbonated soft drinks (OR = 1.6, CI 1.1–2.5) and regular tooth cleaning (OR = 1.7, CI 1.1–2.6) were independently associated with dental erosion. Using teeth as a tool for: biting nails (OR = 1.9, CI 1.4–2.4), opening soda (OR = 1.8, CI 1.4–2.4) and holding needles (OR = 1.6, CI 1.3–2.1) were covariates for tooth wear. Adolescents who reported to clench/grind their teeth (OR = 2.3, CI 1.5–3.7) was the only covariate for TMD. In several of the investigated factors, there were significant differences between the Maasai and non Maasai ethnic groups. Conclusion: Oral health related behaviors have a significant impact on oral diseases/conditions among adolescents attending primary schools in Maasai population areas with obvious differences in behavior between the Maasai and non Maasai ethnic groups. There is a need for addressing oral health and to encourage behaviors that promote good oral health and dental care service utilization in this society.publishedVersio

Eating disorders - knowledge, attitudes, management and clinical experience of Norwegian dentists

Background The purpose of this study was to investigate knowledge, attitudes and clinical experience with regard to patients with eating disorders (ED) among Norwegian dentists. Methods In 2010, a questionnaire was sent to all dentists in Norway (N = 4282) comprising 33 questions related to demographics of the participating dentists, their knowledge of ED (general and oral health aspects), clinical experience, attitudes and perceived management preferences. Results The participation rate was 40 % (47 % women and 53 % men). Their knowledge about ED was often retrieved from common media sources and the greater part of the participants reported they had seen very few patients with ED during their professional career. Female dentists reported superior knowledge about ED compared to males, but the former experienced greater difficulties to inform about the condition. Referrals of the patient to other health facilities were significantly more common among female compared to male dentists. The majority of dentists (76 %) reported a need of more education related to ED management. Conclusions The Norwegian dentists in this study reported limited clinical experience and insufficient knowledge regarding ED. There is therefore a need to increase both undergraduate and continuing education in this field, which can improve preventive and management measures that a dentist can provide for ED patients.publishedVersio

Oral impacts on daily performances and its socio-demographic and clinical distribution: a cross-sectional study of adolescents living in Maasai population areas, Tanzania

Background In a global perspective, oral health among adolescents has improved during recent decades. However, oral problems still persist especially in many underprivileged societies. This study aimed to estimate the prevalence of oral impacts in adolescents and to identify important clinical- and socio-demographic covariates. In addition, this study compares Maasai and non-Maasai adolescents regarding any association of socio-demographic and clinical covariates with oral impacts on daily performances. Methods A total of 989 adolescents were invited from 23 randomly selected public primary schools in Monduli and Longido districts, Tanzania. All adolescents attending 6th grade classes were invited to participate. A total of 930 accepted and of those 24 were excluded, leaving 906 (91.6%) participants for the study. Results A total of 143/906 (15.8%) had at-least one oral impact on daily performances (OIDP > 0), 14.6% among the Maasai and 20.5% among the non-Maasai ethnic group. Cluster adjusted logistic regression revealed that: adolescents from Longido district (OR = 0.4) and adolescents with good oral hygiene (OR = 0.7) were less likely to report OIDP> 0 and; non Maasai (OR = 1.6), those with least poor parents (OR = 2.0), DMFT> 0 (OR = 3.1) and those with positive answers to questions regarding TMD pain, 2Q/TMD > 0 (OR = 3.9) were more likely to report OIDP> 0. Stratified logistic regression by ethnicity revealed that, among the non-Maasais, older adolescents (OR = 3.7, 95% CI 1.1–12.8), those with DMFT> 0 (OR = 3.3 (1.2–9.0) and 2Q/TMD > 0 (OR = 9.0, 95% CI 3.3–25.0) were more likely to report at least one OIDP. The corresponding figures among the Maasais were (OR = 0.9, 95% CI 0.5–1.7), (OR = 2.8, 95% CI 1.4–5.5) and (OR = 3.0, 95% CI 1.7–5.2), respectively. Conclusions The prevalence of oral impacts was moderate but higher among the non-Maasai- than Maasai-adolescents attending rural primary schools in the Maasai population areas of Tanzania. This study also confirmed socioeconomic and oral clinical disparities in OIDP, some of which differed according to ethnicity. Caries experience and self-reported TMD pain associated more strongly with OIDP among the non-Maasais than among the Maasais. These results are important for public oral health decision makers who plan strategies for optimal primary oral health care and quality of life among adolescents belonging to minority groups in Tanzania.publishedVersio

A diet based on multiple functional concepts improves cardiometabolic risk parameters in healthy subjects

Background: Different foods can modulate cardiometabolic risk factors in persons already affected by metabolic alterations. The objective of this study was to assess, in healthy overweight individuals, the impact of a diet combining multiple functional concepts on risk markers associated with cardiometabolic diseases (CMD). Methods: Fourty-four healthy women and men (50-73 y.o, BMI 25-33, fasting glycemia <= 6.1 mmol/L) participated in a randomized crossover intervention comparing a multifunctional (active) diet (AD) with a control diet (CD) devoid of the "active" components. Each diet was consumed during 4 wk with a 4 wk washout period. AD included the following functional concepts: low glycemic impact meals, antioxidant-rich foods, oily fish as source of long-chain omega-3 fatty acids, viscous dietary fibers, soybean and whole barley kernel products, almonds, stanols and a probiotic strain (Lactobacillus plantarum Heal19/DSM15313). Results: Although the aim was to improve metabolic markers without promoting body weight loss, minor weight reductions were observed with both diets (0.9-1.8 +/- 0.2%; P < 0.05). CD did not modify the metabolic variables measured. AD promoted significant changes in total serum cholesterol (-26 +/- 1% vs baseline; P < 0.0001), LDL-cholesterol (-34 +/- 1%; P < 0.0001), triglycerides (-19 +/- 3%; P = 0.0056), LDL/HDL (-27 +/- 2%; P < 0.0001), apoB/apoA1 (-10 +/- 2%; P < 0.0001), HbA1c (-2 +/- 0.4%; P = 0.0013), hs-CRP (-29 +/- 9%; P = 0.0497) and systolic blood pressure (-8 +/- 1%, P = 0.0123). The differences remained significant after adjustment for weight change. After AD, the Framingham cardiovascular risk estimate was 30 +/- 4% (P < 0.0001) lower and the Reynolds cardiovascular risk score, which considers CRP values, decreased by 35 +/- 3% (P < 0.0001). Conclusion: The improved biomarker levels recorded in healthy individuals following the multifunctional regime suggest preventive potential of this dietary approach against CMD

Young Peoples’ Online Science Practices as a Gateway to Higher Education STEM

The purpose of this manuscript is to explore how students perceive that online practices have enabled their participation in university physics programmes. In order to conceptualise how students bridge their science participation across physical and online spaces, we make use of the learning ecology perspective. This perspective is complemented with the notion of science capital, analysing how students have been able to strengthen different aspects of science capital through online participation. Data has been generated through semi-structured interviews guided by a timeline, constructed in collaboration between the interviewer and the interviewee. Twenty-one students enrolled in higher education physics have been interviewed, with a focus on their trajectories into higher education physics. The findings focus on four students who in various ways all have struggled to access science learning resources and found ways to utilise online spaces as a complement to their physical learning ecologies. In the manuscript, we show how online practices have contributed to the students’ learning ecologies, e.g. in terms of building networks and functioning as learning support, and how resources acquired through online science practices have both use and exchange value in the wider science community. Online science participation is thus both curiosity driven and founded in instrumental reasons (using online tutoring to pass school science). Furthermore, we argue that online spaces have the potential to offer opportunities for participation and network building for students who do not have access to science activities and science people in their everyday surroundings.The purpose of this manuscript is to explore how students perceive that online practices have enabled their participation in university physics programmes. In order to conceptualise how students bridge their science participation across physical and online spaces, we make use of the learning ecology perspective. This perspective is complemented with the notion of science capital, analysing how students have been able to strengthen different aspects of science capital through online participation. Data has been generated through semi-structured interviews guided by a timeline, constructed in collaboration between the interviewer and the interviewee. Twenty-one students enrolled in higher education physics have been interviewed, with a focus on their trajectories into higher education physics. The findings focus on four students who in various ways all have struggled to access science learning resources and found ways to utilise online spaces as a complement to their physical learning ecologies. In the manuscript, we show how online practices have contributed to the students’ learning ecologies, e.g. in terms of building networks and functioning as learning support, and how resources acquired through online science practices have both use and exchange value in the wider science community. Online science participation is thus both curiosity driven and founded in instrumental reasons (using online tutoring to pass school science). Furthermore, we argue that online spaces have the potential to offer opportunities for participation and network building for students who do not have access to science activities and science people in their everyday surroundings