Quantum-coherent dynamics in photosynthetic charge separation revealed by wavelet analysis

Experimental/theoretical evidence for sustained vibration-assisted electronic (vibronic) coherence in the Photosystem II Reaction Center (PSII RC) indicates that photosynthetic solar-energy conversion might be optimized through the interplay of electronic and vibrational quantum dynamics. This evidence has been obtained by investigating the primary charge separation process in the PSII RC by two-dimensional electronic spectroscopy (2DES) and Redfield modeling of the experimental data. However, while conventional Fourier transform analysis of the 2DES data allows oscillatory signatures of vibronic coherence to be identified in the frequency domain in the form of static 2D frequency maps, the real-time evolution of the coherences is lost. Here we apply for the first time wavelet analysis to the PSII RC 2DES data to obtain time-resolved 2D frequency maps. These maps allow us to demonstrate that i) coherence between the excitons initiating the two different charge separation pathways is active for more than 500 fs, and ii) coherence between exciton and charge-transfer states, the reactant and product of the charge separation reaction, respectively, is active for at least 1 ps. These findings imply that the PSII RC employs coherence i) to sample competing electron transfer pathways, and ii) to perform directed, ultrafast and efficient electron transfer.Comment: Scientific reports 201

Association between the preoperative fasting and postprandial C-peptide AUC with resolution of type 2 diabetes 6 months following bariatric surgery

Background and AimsBariatric surgery results in the remission of type 2 diabetes mellitus (T2DM) in morbidly obese subjects. The aim of the study was to investigate the predictive value of both static and dynamic measures of C-peptide in relation to T2DM resolution 6 months after bariatric surgery regardless of the operation type.Methods and ResultsA non-randomized prospective study of 24 participants with T2DM undergoing bariatric surgery. Measurements of fasting and 2-hour plasma glucose, insulin, C-peptide and measures of insulin sensitivity were recorded temporally during an oral glucose tolerance test pre-operatively and 6 months post-operatively. A responder was defined with a fasting glucose < 5.6mmol/L and HBA1c < 6.0% postoperatively. Within the sample there were 11 responders and 13 non-responders at 6 months. There was a significant difference in the duration of diabetes between the groups. Fasting C-peptide (P≤0.05) and 2-hour C-peptide (P≤0.05) were higher in responders compared to non-responders. Significantly higher C-peptide levels were observed preoperatively at all time points for responders, with significantly higher area under the curve (AUC0–60 and AUC0–120). Using the lower quartiles for C-peptide levels, both fasting C-peptide (> 2.5ng/mL [0.83nmol/L]) and 2-hour C-peptide (> 5.2ng/mL [1.73nmol/L]) had a sensitivity and negative predictive value of 100% to predict T2DM remission. Logistic regression showed C-peptide, duration of diabetes and BMI were associated with response. The area under the ROC curve was 0.94 and a regression model predicted diabetes remission with a sensitivity of 85.7% and a specificity of 88.9%.ConclusionsThis study demonstrated that static (fasting) and dynamic (AUC, 2-hour) C-peptide measurements predict T2DM resolution 6 months following bariatric surgery. This work provides insight into C-peptide dynamics as a predictor of response to bariatric surgery

Narratives of therapeutic art-making in the context of marital breakdown: Older women reflect on a significant mid-life experience

This paper explores the narratives of three women aged 65-72 years. They reflected on an episode of therapeutic art-making in midlife, which addressed depression associated with marital crisis and breakdown. The narrative analysis focused upon on the ways in which participants narrated the events leading up to their participation in therapeutic art-making; the aspects of therapeutic art-making that continued to be given significance; the characters given primacy in the stories they told about their journey through therapy and marital breakdown; meanings, symbolic and otherwise, that participants ascribed to their artwork made during this turning point in their lives; and aspects of the narratives that conveyed present-day identities and artistic endeavors. The narratives revealed the complexity of the journey through marital breakdown and depression into health, and showed that therapeutic art-making could best be understood, not as a stand-alone experience, but as given meaning within the context of wider personal and social resources. Participants looked back on therapeutic art-making that occurred two decades earlier and still described this as a significant turning point in their personal development. Art as an adjunct to counselling/therapy was not only symbolically self-expressive but provided opportunity for decision-making, agency and a reformulated self-image

Bariatric surgery is accompanied by changes in extracellular vesicle-associated and plasma Fatty Acid Binding Protein 4

BACKGROUND: Bariatric surgery markedly reduces fat mass with beneficial effects on cardiometabolic health but the mechanisms involved are not fully understood. Extracellular vesicles (EVs) are secreted by a variety of cells, including adipocytes, and may mediate some of these benefits. However, the effects of bariatric surgery on circulating EVs are unclear. METHODS: Concentration of plasma EVs isolated by ultracentrifugation at baseline, 1 and 6 months post-bariatric surgery (n = 20) was established using Nanoparticle Tracking Analysis. EV origin (CD9: exosome; CD41: platelet; CD235a: erythrocyte; CD11b: leukocyte; CD144: endothelial), cytokine (interferon γ, interleukin-6, TNF-α) and adipocyte marker (adiponectin, FABP4, PPARγ) expression was measured by time-resolved fluorescence immunoassay. RESULTS: EV concentration and cell-of-origin markers (CD41, CD235a, CD11b, CD144) did not alter in response to surgery, neither did EV-expressed interferon γ, IL-6, TNF-α, adiponectin, PPARγ or CD9. EV-derived fatty acid binding protein 4 (FABP4) increased at 1 month (+ 49%) before returning to baseline by 6 months (- 51%, p < 0.05), corresponding to similar changes in circulating plasma FABP4 (+ 22 and - 24% at 1 and 6 months, respectively; p < 0.001). Patients who underwent biliopancreatic diversion had lower FABP4-expressing EVs at 6 months compared to those who underwent sleeve gastrectomy/gastric banding (p < 0.05), despite similar percentage weight reduction (- 19 vs - 20%, respectively). CD9 expression correlated with EV-expressed FABP4, adiponectin, TNF-α and interferon γ (r = 0.5, r = 0.59, r = 0.53, r = 0.41, respectively, p < 0.005), suggesting transport by an EV population of exosomal rather than microvesicular origin. CONCLUSIONS: Bariatric surgery leads to a transient change in circulating EV- and plasma-derived FABP4, reflecting alterations in adipose tissue homeostasis

Bacterial diseases of bananas and enset: Current state of knowledge and integrated approaches toward sustainable management

Bacterial diseases of bananas and enset have not received, until recently, an equal amount of attention compared to other major threats to banana production such as the fungal diseases black leaf streak (Mycosphaerella fijiensis) and Fusarium wilt (Fusarium oxysporum f. sp. cubense). However, bacteria cause significant impacts on bananas globally and management practices are not always well known or adopted by farmers. Bacterial diseases in bananas and enset can be divided into three groups: (1) Ralstonia-associated diseases (Moko/Bugtok disease caused by Ralstonia solanacearum and banana blood disease caused by R. syzygii subsp. celebesensis); (2) Xanthomonas wilt of banana and enset, caused by Xanthomonas campestris pv. musacearum and (3) Erwinia-associated diseases (bacterial head rot or tip-over disease Erwinia carotovora ssp. carotovora and E. chrysanthemi), bacterial rhizome and pseudostem wet rot (Dickeya paradisiaca formerly E. chrysanthemi pv. paradisiaca). Other bacterial diseases of less widespread importance include: bacterial wilt of abaca, Javanese vascular wilt and bacterial fingertip rot (probably caused by Ralstonia spp., unconfirmed). This review describes global distribution, symptoms, pathogenic diversity, epidemiology and the state of the art for sustainable disease management of the major bacterial wilts currently affecting banana and enset. (Résumé d'auteur

Constructing the Military Hero

Today we see an increase in the usage of the term hero. Especially in the media, the term is applied not only to those who do specific heroic deeds but to entire professions, e.g., the military. In this paper, we analyze the media's social construction of military heroes with respect to four individuals, two fictional characters and two real people. We argue that four themes are essential to the construction of the military hero whether for fictional or real people: a biography; strength of purpose; gender; and the reinforcement of national values. Once constructed in the media, the hero often contributes to political ends by reinforcing national values. More specifically, in their construction military heroes reflect and reproduce ideologies that legitimate the state and its military aggressiveness

Visual art-making as a resource for living positively with arthritis: An interpretative phenomenological analysis of older women’s accounts

This is the post-print version of the final paper published in Journal of Aging Studies. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.This study explored whether and how visual art-making, as a leisure activity, provided a coping resource for older women affected by arthritis. Twelve older women (aged 62–81) were interviewed. They had lived with arthritis for many years, and engaged in arts and crafts regularly. Transcripts were explored through Interpretative Phenomenological Analysis. Three main themes were identified. Firstly, most participants experienced art-making as a powerful means of controlling arthritis pain, through deep concentration, and through use of color and imagery. Secondly, participants experienced art-making as encouraging sustained attention to the outside world, offering psychological escape from the confines of the body and home. Thirdly, art-making protected and promoted identity, for example, through integrating current and former selves, enabling participants to express and re-experience certain valued memories, and engage in personal development. Some participants felt able to celebrate positive difference from others, on the basis of their art rather than their illness

Changes in plasma levels of N-arachidonoyl ethanolamine and N-palmitoylethanolamine following bariatric surgery in morbidly obese females with impaired glucose homeostasis

Aim: We examined endocannabinoids (ECs) in relation to bariatric surgery and the association between plasma ECs and markers of insulin resistance. Methods: A study of 20 participants undergoing bariatric surgery. Fasting and 2-hour plasma glucose, lipids, insulin, and C-peptide were recorded preoperatively and 6 months postoperatively with plasma ECs (AEA, 2-AG) and endocannabinoid-related lipids (PEA, OEA). Results: Gender-specific analysis showed differences in AEA, OEA, and PEA preoperatively with reductions in AEA and PEA in females postoperatively. Preoperatively, AEA was correlated with 2-hour glucose (r = 0.55, P = 0.01), HOMA-IR (r = 0.61, P = 0.009), and HOMA %S (r = -0.71, P = 0.002). OEA was correlated with weight (r = 0.49, P = 0.03), waist circumference (r = 0.52, P = 0.02), fasting insulin (r = 0.49, P = 0.04), and HOMA-IR (r = 0.48, P = 0.05). PEA was correlated with fasting insulin (r = 0.49, P = 0.04). 2-AG had a negative correlation with fasting glucose (r = -0.59, P = 0.04). Conclusion: Gender differences exist in circulating ECs in obese subjects. Females show changes in AEA and PEA after bariatric surgery. Specific correlations exist between different ECs and markers of obesity and insulin and glucose homeostasis

Host circadian clocks do not set the schedule for the within-host replication of malaria parasites

Circadian clocks coordinate organisms' activities with daily cycles in their environment. Parasites are subject to daily rhythms in the within-host environment, resulting from clock-control of host activities, including immune responses. Parasites also exhibit rhythms in their activities: the timing of within-host replication by malaria parasites is coordinated to host feeding rhythms. Precisely which host feeding-related rhythm(s) parasites align with and how this is achieved are unknown. Understanding rhythmic replication in malaria parasites matters because it underpins disease symptoms and fuels transmission investment. We test if rhythmicity in parasite replication is coordinated with the host's feeding-related rhythms and/or rhythms driven by the host's canonical circadian clock. We find that parasite rhythms coordinate with the time of day that hosts feed in both wild-type and clock-mutant hosts, whereas parasite rhythms become dampened in clock-mutant hosts that eat continuously. Our results hold whether infections are initiated with synchronous or with desynchronized parasites. We conclude that malaria parasite replication is coordinated to rhythmic host processes that are independent of the core-clock proteins PERIOD 1 and 2; most likely, a periodic nutrient made available when the host digests food. Thus, novel interventions could disrupt parasite rhythms to reduce their fitness, without interference by host clock-controlled homeostasis