Light use efficiency at different wavelengths in rose plants

Current knowledge about the spectral dependence of leaf light use efficiency of leaf photosynthesis (LUE; rate of leaf photosynthesis per unit incident light energy) is based on investigations of mostly arable crops. The leaf LUE depends on the optical properties of the leaf (light absorption), on the fraction of light energy absorbed by photosynthetically active pigments and on the excitation balance of the two photosystems. These properties have hardly been investigated on modern vegetable and especially ornamental greenhouse crops. In this research we investigated the action spectrum of leaf photosynthesis and related leaf optical properties of reddish young leaves and green middle aged leaves of rose ‘Akito’. The crop was grown in a heated greenhouse in Wageningen (The Netherlands, latitude 52°N). The green and reddish leaves had similar total absorptance of 87% on average in the PAR range (400 to 700 nm). In the green leaves, however, leaf absorptance around 550 nm was lower than in the reddish leaves, but slightly higher at longer wavelengths. Red light of 680 nm was found to be the most effective for leaf photosynthesis in the short term. Leaf LUEs were calculated for supplemental light by HPS and 645 and 680 nm LEDs based on their emission spectra and the measured action spectra of leaf photosynthesis. These calculations showed that a 645 nm LED light yielded more improvement in LUE compared to HPS light than 680 nm LED light. This is because the 680 nm LED also emits light >700 nm at which the LUE is much lower. If these calculated improvements in leaf LUE for red LED-light compared to HPS-light are sustained at the crop level during prolonged illumination, substantial energy savings may be realized in rose by supplemental lighting with red LED ligh

Neural responses to facial and vocal expressions of fear and disgust

Neuropsychological studies report more impaired responses to facial expressions of fear than disgust in people with amygdala lesions, and vice versa in people with Huntington's disease. Experiments using functional magnetic resonance imaging (fMRI) have confirmed the role of the amygdala in the response to fearful faces and have implicated the anterior insula in the response to facial expressions of disgust. We used fMRI to extend these studies to the perception of fear and disgust from both facial and vocal expressions. Consistent with neuropsychological findings, both types of fearful stimuli activated the amygdala. Facial expressions of disgust activated the anterior insula and the caudate-putamen; vocal expressions of disgust did not significantly activate either of these regions. All four types of stimuli activated the superior temporal gyrus. Our findings therefore (i) support the differential localization of the neural substrates of fear and disgust; (ii) confirm the involvement of the amygdala in the emotion of fear, whether evoked by facial or vocal expressions; (iii) confirm the involvement of the anterior insula and the striatum in reactions to facial expressions of disgust; and (iv) suggest a possible general role for the perception of emotional expressions for the superior temporal gyrus

Population coding by globally coupled phase oscillators

A system of globally coupled phase oscillators subject to an external input is considered as a simple model of neural circuits coding external stimulus. The information coding efficiency of the system in its asynchronous state is quantified using Fisher information. The effect of coupling and noise on the information coding efficiency in the stationary state is analyzed. The relaxation process of the system after the presentation of an external input is also studied. It is found that the information coding efficiency exhibits a large transient increase before the system relaxes to the final stationary state.Comment: 7 pages, 9 figures, revised version, new figures added, to appear in JPSJ Vol 75, No.

Dense, low-power sensor network for three-dimensional thermal characterization of large-scale atria spaces

We describe the design and implementation of a dense, low-power wireless sensor network for fine-grained three-dimensional thermal characterization of a large open indoor space. To better understand the airflow dynamics and ensuing energy efficiency potential of this type of modern architectural design, we developed a sustainable wireless mesh network consisting of 50 sensors hung on an array of thin cables in a 210 m[superscript 2], 14.2 m tall atrium for real-time temperature and humidity monitoring. The goal is to create compact wireless measurement sensor blocks for dense coverage in the building. We demonstrate the implementation through a preliminary analysis, which includes the evaluation of temperature distribution discrepancies with computer-simulated results and data taken during natural ventilation to illustrate the nontrivial, well-mixed temperatures observed during the studies.Massachusetts Institute of Technology. Media LaboratorySchneider Electric (Firm

Endogenous cholinergic inputs and local circuit mechanisms govern the phasic mesolimbic dopamine response to nicotine

Nicotine exerts its reinforcing action by stimulating nicotinic acetylcholine receptors (nAChRs) and boosting dopamine (DA) output from the ventral tegmental area (VTA). Recent data have led to a debate about the principal pathway of nicotine action: direct stimulation of the DAergic cells through nAChR activation, or disinhibition mediated through desensitization of nAChRs on GABAergic interneurons. We use a computational model of the VTA circuitry and nAChR function to shed light on this issue. Our model illustrates that the α4β2-containing nAChRs either on DA or GABA cells can mediate the acute effects of nicotine. We account for in vitro as well as in vivo data, and predict the conditions necessary for either direct stimulation or disinhibition to be at the origin of DA activity increases. We propose key experiments to disentangle the contribution of both mechanisms. We show that the rate of endogenous acetylcholine input crucially determines the evoked DA response for both mechanisms. Together our results delineate the mechanisms by which the VTA mediates the acute rewarding properties of nicotine and suggest an acetylcholine dependence hypothesis for nicotine reinforcement.Peer reviewe

Soft capacitor fibers using conductive polymers for electronic textiles

A novel, highly flexible, conductive polymer-based fiber with high electric capacitance is reported. In its crossection the fiber features a periodic sequence of hundreds of conductive and isolating plastic layers positioned around metallic electrodes. The fiber is fabricated using fiber drawing method, where a multi-material macroscopic preform is drawn into a sub-millimeter capacitor fiber in a single fabrication step. Several kilometres of fibers can be obtained from a single preform with fiber diameters ranging between 500um -1000um. A typical measured capacitance of our fibers is 60-100 nF/m and it is independent of the fiber diameter. For comparison, a coaxial cable of the comparable dimensions would have only ~0.06nF/m capacitance. Analysis of the fiber frequency response shows that in its simplest interrogation mode the capacitor fiber has a transverse resistance of 5 kOhm/L, which is inversely proportional to the fiber length L and is independent of the fiber diameter. Softness of the fiber materials, absence of liquid electrolyte in the fiber structure, ease of scalability to large production volumes, and high capacitance of our fibers make them interesting for various smart textile applications ranging from distributed sensing to energy storage

BRCA1/BRCA2 rearrangements and CHEK2 common mutations are infrequent in Italian male breast cancer cases.

Male breast cancer (MBC) is a rare and poorly known disease. Germ-line mutations of BRCA2 and, to lesser extent, BRCA1 genes are the highest risk factors associated with MBC. Interestingly, BRCA2 germ-line rearrangements have been described in high-risk breast/ovarian cancer families which included at least one MBC case. Germ-line mutations of CHEK2 gene have been also implicated in inherited MBC predisposition. The CHEK2 1100delC mutation has been shown to increase the risk of breast cancer in men lacking BRCA1/BRCA2 mutations. Intriguingly, two other CHEK2 mutations (IVS2+1G > A and I157T) and a CHEK2 large genomic deletion (del9-10) have been associated with an elevated risk for prostate cancer. Here, we investigated the contribution of BRCA1, BRCA2 and CHEK2 alterations to MBC predisposition in Italy by analysing a large series of MBC cases, unselected for breast cancer family history and all negative for BRCA1/BRCA2 germ-line mutations. A total of 102 unrelated Italian MBC cases were screened for deletions/duplications of BRCA1, BRCA2 and CHEK2 by multiplex ligation-dependent probe amplification. No BRCA1, BRCA2 and CHEK2 genomic rearrangements, including the CHEK2 del9-10, were found in the series analysed. Furthermore, none of the MBC cases and 263 male population controls, also included in this study, carried the CHEK2 1100delC, IVS2+1G > A and I157T common mutations. Overall, our data suggest that screening of BRCA1/2 rearrangements is not advantageous in MBC cases not belonging to high-risk breast cancer families and that common CHEK2 mutations play an irrelevant role in MBC predisposition in Italy

Using Generative AI to Remove Barriers in Support of Open Content Creation

Open content, such as textbook-length open educational resources (OER) or smaller pieces like an assignment, can offer numerous benefits to students by being free, diverse, and effective replacements for traditional textbooks, but there are limited open resources and difficulties creating new open content. This poster explores how generative AI can remove these barriers, enabling instructors to have time and support to create and use open content in their courses. By highlighting use cases, attendees will see how to do this approach in their own classroom, regardless of modality or discipline. Important considerations will be addressed, including usage, sharing, and ethics. This poster presentation was presented at Teaching and Learning with AI Conference 2023

The 5-Ps of Jumpstarting Open Assessment Creation with Generative AI

Generative Artificial Intelligence (AI trained on Large Language Models to generate text) has exploded into the digital learning space. As the need for Open Educational Resources (OER) also continues to grow, generative AI can jumpstart aspects of OER creation. This presentation will consider barriers to OER adoption, including the availability of supplemental teaching resources, and will propose a use case for leveraging AI text-generation to support best practices for creating unique assessment questions. Through the “5-Ps,” – Problem, Past, Present, Possibilities, and Product – we will consider the ways that adopters, adapters, and authors of OER can use generative AI to support access, innovation, and evaluation. We will consider OER adoption through the lenses of textbook affordability and instructional design to propose a framework for using generative-AI so that open education reaches more learners while maintaining the principles of research-backed assessment practices. This is a presentation for the Open Education Conference 2023

Polarized distribution of HCO3- transport in human normal and cystic fibrosis nasal epithelia

The polarized distribution of HCO3− transport was investigated in human nasal epithelial cells from normal and cystic fibrosis (CF) tissues. To test for HCO3− transport via conductive versus electroneutral Cl−/HCO3− exchange (anion exchange, AE) pathways, nasal cells were loaded with the pH probe 2′,7′-bis(carboxyethyl)-5(6)-carboxyfluorescein and mounted in a bilateral perfusion chamber. In normal, but not CF, epithelia, replacing mucosal Cl− with gluconate caused intracellular pH (pHi) to increase, and the initial rates (ΔpH min−1) of this increase were modestly augmented (∼26 %) when normal cells were pretreated with forskolin (10 μm). Recovery from this alkaline shift was dependent on mucosal Cl−, was insensitive to the AE inhibitor 4,4′-diisothiocyanatodihydrostilbene-2,2′-disulfonic acid (H2DIDS; 1.5 mm), but was sensitive to the cystic fibrosis transmembrane conductance regulator (CFTR) channel inhibitor diphenylamine-2-carboxylate (DPC; 100 μm). In contrast, removal of serosal Cl− caused pHi to alkalinize in both normal and CF epithelia. Recovery from this alkaline challenge was dependent on serosal Cl− and blocked by H2DIDS. Additional studies showed that serosally applied Ba2+ (5.0 mm) in normal, but not CF, cells induced influx of HCO3− across the apical membrane that was reversibly blocked by mucosal DPC. In a final series of studies, normal and CF cells acutely alkaline loaded by replacing bilateral Krebs bicarbonate Ringer (KBR) with Hepes-buffered Ringer solution exhibited basolateral, but not apical, recovery from an alkaline challenge that was dependent on Cl−, independent of Na+ and blocked by H2DIDS. We conclude that: (1) normal, but not CF, nasal epithelia have a constitutively active DPC-sensitive HCO3− influx/efflux pathway across the apical membrane of cells, consistent with the movement of HCO3− via CFTR; and (2) both normal and CF nasal epithelia have Na+-independent, H2DIDS-sensitive AE at their basolateral domain