Mushroom body subsets encode CREB2-dependent water-reward long-term memory in Drosophila.

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.

Associations between gene expression of magnesium transporters and glucose metabolism in pregnancy.

BACKGROUND/PURPOSE: To assess the relationship between gene expressions of the magnesium transporters and glucose parameters in pregnant women. METHODS: A cohort of women without ongoing or prior medical illnesses was recruited at the start of an early singleton pregnancy. Expression levels of the magnesium transporters-SLC41A1, CNNM2, MAGT1, TRPM6, and TRPM7-were assessed in the peripheral leukocytes, while total calcium and magnesium were assessed in the serum between 10 and 13 weeks gestation. Glucose parameters were assessed between 24 and 28 weeks gestation using the 75 g oral glucose tolerance test. RESULTS: A total of 208 patients were included in the study. The expressions of the magnesium transports were generally unrelated to age, body mass index (BMI), or serum levels of calcium and magnesium. The magnesium transporters were correlated with each other at baseline (correlation coefficients: 0.31 to 0.51). BMI was a strong predictor of fasting glucose levels, while both BMI and age were strong predictors of post-load glucose levels. The expression of TRPM7 was found to be predictive of 1-h post-load blood glucose after accounting for the effects of age and BMI (ß = -0.196, p = 0.020). CONCLUSION: The increased maternal expression of the magnesium transporter TRPM7 may be associated with decreased glucose tolerance in pregnant women. In particular, the association between TRPM7 and 1-h post-load glucose levels was found to be independent of the effects of age and BMI. Future studies are needed to determine whether a mechanistic relationship can be demonstrated between TRPM7 and glucose metabolism.

Additive Expression of Consolidated Memory through Drosophila Mushroom Body Subsets.

Associative olfactory memory in Drosophila has two components called labile anesthesia-sensitive memory and consolidated anesthesia-resistant memory (ARM). Mushroom body (MB) is a brain region critical for the olfactory memory and comprised of 2000 neurons that can be classified into αß, α'ß', and γ neurons. Previously we demonstrated that two parallel pathways mediated ARM consolidation: the serotonergic dorsal paired medial (DPM)-αß neurons and the octopaminergic anterior paired lateral (APL)-α'ß' neurons. This finding prompted us to ask how this composite ARM is retrieved. Here, we showed that blocking the output of αß neurons and that of α'ß' neurons each impaired ARM retrieval, and blocking both simultaneously had an additive effect. Knockdown of radish and octß2R in αß and α'ß' neurons, respectively, impaired ARM. A combinatorial assay of radish mutant background rsh1 and neurotransmission blockade confirmed that ARM retrieved from α'ß' neuron output is independent of radish. We identified MBON-ß2ß'2a and MBON-ß'2mp as the MB output neurons downstream of αß and α'ß' neurons, respectively, whose glutamatergic transmissions also additively contribute to ARM retrieval. Finally, we showed that α'ß' neurons could be functionally subdivided into α'ß'm neurons required for ARM retrieval, and α'ß'ap neurons required for ARM consolidation. Our work demonstrated that two parallel neural pathways mediating ARM consolidation in Drosophila MB additively contribute to ARM expression during retrieval.

Genetic algorithms optimization of photonic crystal fibers for half diffraction angle reduction of output beam.

In this work, we optimize the structure of the photonic crystal fibers by using genetic algorithms to provide strong light confinement in fiber and small half diffraction angle of output beam. Furthermore, this article shows the potentials of this study, such as optimizing three purposes at the same time and the arbitrary structure design is achieved. We report two optimized results obtained by different optimization conditions. The results show that the half diffraction angle of the output beam of the photonic crystal fibers can be reduced.

Monitoring Arctic permafrost coastal erosion dynamics using a multidecadal cross-mission SAR dataset along an Alaskan Beaufort Sea coastline.

Arctic coasts are transition zones influenced by terrestrial, marine, and cryospheric factors. Due to the degradation of the cryosphere exacerbated by climate change, many segments of Arctic coasts are characterized by severe erosions and thus resulting in many social-economic consequences. To assess the imminent coastal risks and increasing organic carbon fluxes released from Arctic erosional coasts, continuous monitoring of shoreline movement is necessary. Conventional studies employ spaceborne multi-spectral optical images to detect ample Arctic coasts' dynamics; nonetheless, the frequent cloud cover and Arctic haze limit the number of usable images. Thence, most studies merely utilize a few image pairs to estimate long-term rate changes, which deter statistically meaningful trend analysis and are likely biased by intra-annual variations. This study employs cross-mission synthetic aperture radar (SAR) images that are cloud-penetrating and weather-independent to depict 32-year spatiotemporal changes of Drew Point Coast along the Alaskan Beaufort Sea. To efficiently and robustly extract shorelines, a non-manual intervention-required and cross-SAR sensor applicable approach is proposed. Based on the automatically delineated time series shoreline positions, each coastal segment's position-time records are modeled with a statistic-based coastal dynamics classification scheme that enables constructing non-linear trends of inter-decadal recession rates. Results reveal that 83.7 % of the coast exhibits continuous erosion during 1992-2023. Dynamically, 48.6 % of coast demonstrates polynomial change patterns with an erosive rate higher than -6 m/yr. Remarkably, 22.5 % of the coast has been statistically significantly accelerating. For instance, the erosional rate nearly double (93.8 %) between Drew Point and McLeod Point, while between Lonely and Pitt Point, the most erosive segment in the study coast, the retreating rate increases 285.57 % from -5.92 to -22.81 m/yr. These findings exemplify the high heterogeneity of Arctic coastal changes and highlight the opportunities of using spaceborne SAR data to empower the management and conservation of Arctic coasts.

Dienogest treatment in women with endometriosis: A retrospective cohort study in Taiwan.

OBJECTIVE: To assess the treatment efficacy of dienogest specifically in the Taiwanese population with endometriosis. MATERIALS AND METHODS: Eighty-eight patients diagnosed with endometriosis receiving at least 3 months of dienogest 2 mg once daily, from January 2018 to June 2022, were enrolled. They were divided into two groups: surgery group and non-surgery group. The assessment of pain improvement was based on visual analog scale (VAS) scores (0-100 mm) recorded at 0, 3, 6, and 12 months following the initiation of dienogest. Serum CA-125 value and ovarian endometrioma size were analyzed at 0 and 6 months. RESULTS: A total of 65 patients with endometriosis presented painful symptoms. In the surgery group (N = 28), the initial VAS score was 47.5 mm, which significantly declined to 9.6 mm at 3 months (p < 0.01), then to 7.5 mm, 2.9 mm, and 2.1 mm at 6, 9, and 12 months, respectively. In the non-surgery group (N = 37), the initial VAS score was 65.7 mm, which significantly declined to 13.2 mm at 3 months (p < 0.01) and 4.9 mm at 6 months (p < 0.05), remained low at 0.3 mm at both 9 and 12 months. Endometrioma size (N = 33) exhibited a significant 35% decrease from 38.2 mm to 24.8 mm after 6 months treatment (p < 0.01). Serum CA-125 levels showed significant improvement from 86.5 to 30.2 U/ml (p < 0.01) at 6 months. CONCLUSION: This retrospective cohort study proved that dienogest is effective in reducing endometriosis-associated pain and endometrioma size in Taiwanese population.

Sensitive metal layer assisted guided mode resonance biosensor with a spectrum inversed response and strong asymmetric resonance field distribution.

In this paper, a metal layer assisted guide mode resonance (MaGMR) device with high sensitivity is proposed for bioanalytical applications and its functioning is experimentally proved. We find that the reflection spectra present a unique inversed response. The resonance mechanism is also discussed. Numerical calculation results indicate that the high sensitivity performance of MaGMR comes from the strongly asymmetric resonance modal profile and low propagation angle inside the waveguide. There is a one-fold enhancement of the evanescent wave in the analytes region compared to typical GMR. According to the experimental results, the proposed MaGMR achieved a bulk sensitivity of 376.78 nm/RIU in fundamental TM mode resonating at 0.809 µm with the first diffraction angle. Experiment results show a 264.78% enhancement in the sensitivity compared to that of the typical GMR sensor in the same resonance conditions of TM mode.

Monitoring 23-year of shoreline changes of the Zengwun Estuary in Southern Taiwan using time-series Landsat data and edge detection techniques.

More than 80% of sandy beaches in Taiwan have been experiencing a severe recession, although the sediment discharge of rivers in Taiwan is significantly higher than the world average producing almost 2% of global fluvial sediment discharge. This contradiction is primarily due to the widespread constructions of reservoirs and intensive anthropogenic activities in coastal regions. In addition, coasts are particularly vulnerable to hazards due to climate change, such as sea-level rise, as they are located at the transition zone of terrestrial and marine environments. Along with the fact that Taiwan is an island and is one of the most climate-vulnerable regions globally, coastal management and sustainability are nationally critical topics, especially considering the ongoing reformation and legislation of Taiwan's coastal conservation laws. As stated in the Sustainable Development Goals (SDGs) goal 14, accurate and continuous shoreline positions information is essential for coastal conservation. However, by reviewing previous global studies and projects commissioned by the Taiwanese government aiming at monitoring shoreline changes, they usually exhibit several limitations, such as limited band selections or conservative band ratio-derived water indices, relying on either manual digitization or simple thresholding methods, focusing on either artificial or smoothly shaped coasts, and using images acquired at considerably different tidal height levels. Therefore, in the present study, a subpixel shoreline extraction approach based on a sustainable cross-generation dataset and a robust edge detection algorithm is proposed. This approach is exemplified by the Zengwun River Estuary located in southwestern Taiwan-Taiwan's most critical coastal preservation region. By quantitatively analyzing the resultant time-series shoreline positions from 1999 to 2021, several hotspots of shoreline recession have been identified: an extreme erosional rate up to -69.4 m year-1 is revealed in the northern sand bank; while the offshore sand bar demonstrates an overall landward retreat rate of -35.4 ± 1.24 m year-1.

Enhancing the resonance quality factor in membrane-type resonant grating waveguides.

In this Letter, we present a method of reducing the spectral width of guided-mode resonance (GMR) in air-bridged resonant grating-waveguide structures to enhance the Q factor. The posttreatment of adding a dielectric film to the bottom of the membrane to manipulate the resonance behavior is practicable. The introduced underlayer is shown to be capable of effectively reducing the coupling and enhancing the resonant Q factor. The proposed method provides an effective means of adjusting the resonance property without varying the original GMR structure. The results also imply that TM resonance is more feasible for achieving narrow resonance and potentially in sensing applications, because it has higher sensitivity than TE resonance.

Neural circuits for long-term water-reward memory processing in thirsty Drosophila.

The intake of water is important for the survival of all animals and drinking water can be used as a reward in thirsty animals. Here we found that thirsty Drosophila melanogaster can associate drinking water with an odour to form a protein-synthesis-dependent water-reward long-term memory (LTM). Furthermore, we found that the reinforcement of LTM requires water-responsive dopaminergic neurons projecting to the restricted region of mushroom body (MB) ß' lobe, which are different from the neurons required for the reinforcement of learning and short-term memory (STM). Synaptic output from α'ß' neurons is required for consolidation, whereas the output from γ and αß neurons is required for the retrieval of LTM. Finally, two types of MB efferent neurons retrieve LTM from γ and αß neurons by releasing glutamate and acetylcholine, respectively. Our results therefore cast light on the cellular and molecular mechanisms responsible for processing water-reward LTM in Drosophila.

Propagation loss reduction of photonic crystal slab waveguides by microspheres.

Dielectric microspheres are theoretically studied to reduce the propagation loss of Si-based photonic crystal slab waveguides. Two-dimensional photonic crystal formed by etched air hole can act as a template for microsphere sedimentation. The analytical results show that the transmission of the photonic crystal slab waveguides with microspheres can be enhanced to be around twice that without microspheres.