Dependence of reaction center-type energy-dependent quenching on photosystem II antenna size

AbstractThe effects of photosystem II antenna size on reaction center-type energy-dependent quenching (qE) were examined in rice plants grown under two different light intensities using both wild type and qE-less (OsPsbS knockout) mutant plants. Reaction center-type qE was detected by measuring non-photochemical quenching at 50 μmol photons m−2 s−1 white light intensity. We observed that in low light-grown rice plants, reaction center-type qE was higher than in high light-grown plants, and the amount of reaction center-type qE did not depend on zeaxanthin accumulation. This was confirmed in Arabidopsis npq1–2 mutant plants that lack zeaxanthin due to a mutation in the violaxanthin de-epoxidase enzyme. Although the electron transport rate measured at a light intensity of 50 μmol photons m−2 s−1 was the same in high light- and low light-grown wild type and mutant plants lacking PsbS protein, the generation of energy-dependent quenching was completely impaired only in mutant plants. Analyses of the pigment content, Lhcb proteins and D1 protein of PSII showed that the antenna size was larger in low light-grown plants, and this correlated with the amount of reaction center-type qE. Our results mark the first time that the reaction center-type qE has been shown to depend on photosystem II antenna size and, although it depends on the existence of PsbS protein, the extent of reaction center-type qE does not correlate with the transcript levels of PsbS protein. The presence of reaction center-type energy-dependent quenching, in addition to antenna-type quenching, in higher plants for dissipation of excess light energy demonstrates the complexity and flexibility of the photosynthetic apparatus of higher plants to respond to different environmental conditions

Lemierre Syndrome: A Case of Postanginal Sepsis

Lemierre syndrome is a rare disease that's characterized by internal jugular vein thrombosis and septic emboli. These symptoms typically develop after acute oropharyngeal infection by Fusobacterium necrophorum1). Although this syndrome is less frequently seen in modern times due to the availability of antibiotics, physicians must be aware of the syndrome in order to initiate prompt antibiotics therapy, including coverage of the anerobic organisms. We discuss here the case of an 18-year-old female with Lemierre syndrome and we review the relevant literature on this syndrome

Neuropathic Pain Related with Spinal Disorders: A Systematic Review

Systematic literature review. To review the evidence from high-quality studies regarding the treatment of neuropathic pain originating specifically from spinal disorders. In general, treatment guidelines for neuropathic pain cover all its various causes, including medical disease, peripheral neuropathy, and cancer. However, the natural history of neuropathic pain originating from spinal disorders may differ from that of the pain originating from other causes or lesions. An expert research librarian used terms related to neuropathic pain and spinal disorders, disc herniation, stenosis, and spinal cord injury to search in MEDLINE, Embase, and Cochrane CENTRAL for primary research from January 2000 to October 2015. Among 2,313 potential studies of interest, 25 randomized controlled trials (RCTs) and 21 systematic reviews (SRs) were included in the analysis. The selection was decided based on the agreement of two orthopedic surgeons. There was a lack of evidence about medication for radiculopathy arising from disc herniation and stenosis, but intervention procedures, including epidural block, showed positive efficacy in radiculopathy and also limited efficacy in spinal stenosis. There was some evidence based on the short-term follow-up regarding surgery being superior to conservative treatments for radiculopathy and stenosis. There was limited evidence regarding the efficacy of pharmacological and electric or magnetic stimulation therapies for neuropathic pain after spinal cord injury. This review of RCTs and SRs with high-quality evidence found some evidence regarding the efficacy of various treatment modalities for neuropathic pain related specifically to spinal disorders. However, there is a need for much more supportive evidence

CD82/KAI1 Maintains the Dormancy of Long-Term Hematopoietic Stem Cells through Interaction with DARC- Expressing Macrophages

Hematopoiesis is regulated by crosstalk between long-term repopulating hematopoietic stem cells (LT-HSCs) and supporting niche cells in the bone marrow (BM). Here, we examine the role of CD82/ KAI1 in niche-mediated LT-HSC maintenance. We found that CD82/ KAI1 is expressed predominantly on LT-HSCs and rarely on other hematopoietic stem-progenitor cells (HSPCs). In Cd82 +/-/+/- mice, LTHSCs were selectively lost as they exited from quiescence and differentiated. Mechanistically, CD82based TGF-b1/ Smad3 signaling leads to induction of CDK inhibitors and cell-cycle inhibition. The CD82 binding partner DARC/ CD234 is expressed on macrophages and stabilizes CD82 on LT-HSCs, promoting their quiescence. When DARC + BMmacrophages were ablated, the level of surface CD82 on LT-HSCs decreased, leading to cell-cycle entry, proliferation, and differentiation. A similar interaction appears to be relevant for human HSPCs. Thus, CD82 is a functional surface marker of LT-HSCs that maintains quiescence through interaction with DARC-expressing macrophages in the BM stem cell niche.113525Ysciescopu

Increased Transforming Growth Factor-beta1 in Alcohol Dependence

Ethanol and its metabolite acetaldehyde increase transforming growth factor beta1 (TGF-β1) expression in animal studies. TGF-β1 is related with the hepatic stellate cell (the key element of hepatic fibrogenesis) and the radial glia (the key element of neuronal migration). Blood samples were collected from 41 patients with alcohol dependence, TGF-β1 levels measured by ELISA were compared with 41 normal subjects. Plasma TGF-β1 levels in the patients with alcohol dependence (1,653.11±532.45 pg/mL) were significantly higher than those of healthy subjects (669.87±366.53 pg/mL) (P=0.000). Patients with or without liver pathology showed no difference in TGF-β1 (P=0.36). Increased TGF-β1 may mediate deleterious effect of alcohol such as hepatic fibrosis and suppressed neuronal developments in alcohol dependence patients

Teachers’ Epistemological Assumptions about Educational Inequality in Four Societies: A Holistic Reading Strategy for Examining Sociocultural Epistemologies

Conventional approaches to analyzing cross-national data on teacher knowledge have often failed to recognize qualitative variations across and within different countries. A dilemma confronted by researchers is how to avoid the essentialization of cultures while benefiting from cultural intuition by attending to general national patterns. If researchers focus on exploring the diverse subjectivities of respondents, they are not likely to observe general national patterns because subtle nuances in meaning make it challenging to deal with data with broad categories. There may be too many subtle meanings. However, if researchers focus on general national patterns, they may lose the hidden scripts of the data, as little attention is paid to nuanced meanings. Our data suggest that a holistic reading approach examining different types of semantic foci can be an alternative method for dealing with such a methodological dilemma. This study provides an illustrative example analysis based on this alternative analytic approach

High-Tg N-triarylamine derivatives as a hole injecting layer in organic light-emitting diodes

N-triarylamines, m-MTDAPB and 1-TNAPB, with high glass transition temperature and hole affinity were evaluated as a hole injection layer (HIL) in organic light-emitting diodes (OLEDs) with the configuration of ITO/N-triarylamine/-NPD (HTL)/Alq3 (EML)/LiF/Al. The performance of N-triarylamines as HIL in OLEDs was investigated in terms of turn-on voltage, luminescence, color purity, etc. Better EL performance was observed in OLED with m-MTDAPB as HIL, showing turn-on voltage of 6V and maximum luminescence of 2,976cd/m2 at 13.5V. This might be attributed to well-matched HOMO energy offsets at the interfaces of anode/HIL/HTL layers in OLED with the configuration ofITO/m-MTDAPB/-NPD (HTL)/Alq3 (EML)/LiF/Al, compared to OLED with1-TNAPB as HIL.1

Deep Learning for Predicting Winter Temperature in North China

It is difficult to improve the seasonal prediction skill of winter temperature over North China, owing to the complex dynamics of East Asian winter and the relatively low prediction skill level of current climate models. Deep learning (DL) may be an informative and promising tool to enhance seasonal prediction, particularly in regions where the underlying mechanisms are not clear. Here, using a DL model based on the Convolutional Neural Network (CNN), we have found that the prediction skill for North China winter temperature (NCWT) can be extended up to five months by considering the remote impact of the Northeast Pacific sea-surface temperature (SST) on North China. Based on historical simulations of winter temperatures in North China, we selected six CMIP5 models with relatively small deviations for training the CNN, and the period chosen for training was 1852–1991. The ERA5 data during 1995–2017 were utilized to evaluate the performance of the CNN. Our CNN shows the best performance in a recent 10-year period (2008–2017), showing a significantly improved level of NCWT prediction skill with a correlation skill of 0.65 at a 5-month lead time, which is much better than the forecast skill of the state-of-the-art dynamic seasonal prediction system. Heat map analysis was used to explore the possible physical mechanisms associated with the NCWT anomaly from the perspective of the CNN; the results showed that the SST over the Northeast Pacific is highly relevant to NCWT prediction. The Northeast Pacific warming in the boreal summer is related to the development of the El Niño event in the coming winter, which may induce NCWT anomalies by atmospheric teleconnection. Climate model experiments support the role of Northeast Pacific warming in the boreal summer on NCWT. The improved capability for prediction from using the CNN may help to establish the energy policy for the coming winter and reduce the economic losses from extremely cold in North China

Robust H∞ Control For Uncertain Nonlinear Active Magnetic Bearing Systems Via Takagi-Sugeno Fuzzy Models

In this paper, a systematic procedure to design the robust H ∞, fuzzy controller for a nonlinear active magnetic bearing (AMB) system affected by time-varying parametric uncertainties is presented. First, the continuous-time Takagi-Sugeno (T-S) fuzzy model is employed to represent the nonlinear AMB system. Next, based on the obtained fuzzy model, sufficient conditions are derived in terms of linear matrix inequalities (LMIs) for robust stability and H∞, performance of the control system. The main feature of this paper is that some drawbacks existing in the previous approaches such as truncation errors and nonconvex bilinear matrix inequality (BMI) problem are eliminated by utilizing the homogeneous fuzzy model which includes no bias terms in the local state space models rather than the affine one which includes bias terms. Hence, the design method presented here will prove to be more tractable and accessible than the previous ones. Finally, numerical simulations demonstrate the effectiveness of the proposed approach. © ICROS, KIEE and Springer 2010

A Case of Symptomatic Tracheal Diverticulum and Surgical Resection as a Treatment Modality

Tracheal diverticulum is often diagnosed incidentally and, due to its rarity, there is no standard treatment. It is a benign entity, but has the potential to cause specific symptoms, such as chronic upper respiratory infection and chronic cough. Symptomatic tracheal diverticulum can be medically treated, but likelihood of recurrence is high. We report a case of surgical resection of symptomatic tracheal diverticulum to prevent recurrence