Memory Behavior Research Articles

Disruption of exploratory behavior and olfactory memory in cockroaches exposed to sublethal doses of the neonicotinoid Thiamethoxam

Neonicotinoid insecticides (NNI) are agonists of insect nicotinic acetylcholine receptors (nAChR) that induce non-elucidate mechanisms of abnormal behavior in insects. In this work, we investigated the effects of sublethal doses of the neonicotinoid thiamethoxam (TMX) on neurochemical and physiological parameters in cockroaches. Sublethal doses of TMX (0.01–10 ng.g−1 body mass) caused significant alterations in most of the neurophysiological parameters evaluated. TMX reduced sustained locomotor activity by 19.9–25.8 %, depending on the dose. Leg grooming activity increased by 124.5 ± 3.4 %, 158.7 ± 3.5 %, 168.3 ± 3.4 %, and 160.4 ± 3.4 % (mean ± SEM) with TMX doses of 0.01, 0.1, 1, and 10 ng.g−1, respectively. Exploratory activity was significantly reduced only at the lowest TMX dose (0.01 ng.g−1) – the time spent immobile increased from 30 % to ~45 %, whereas none of the doses affected the walking speed. Treatment with TMX (0.01 ng.g−1) markedly reduced the olfactory sensitivity of the cockroaches and also reduced the mechanosensory action potential amplitude, rise time and decay time by 61.2 ± 19 %, 50 ± 4 %, and 76.8 ± 9.5 %, respectively. In semi-isolated heart preparations, TMX caused positive chronotropism (increases of 34.7 ± 15.9 %, 26.8 ± 7.8 %, 43.0 ± 16.5 %, and 19.0 ± 13.7 % for 0.01, 0.1, 1, and 10 ng of TMX, respectively). TMX attenuated the activity of glutathione-S-transferase by 35.1 ± 6.4 % at the highest dose tested (10 ng.g−1). TMX caused alterations in the metal ion content of cockroach brains that varied with the dose tested and the ion examined. These findings indicate that sublethal doses of TMX can interfere with normal neurological function in cockroaches and disrupt brain metal ion homeostasis.

Role of sulphur in resistive switching behavior of natural rubber-based memory

The rising environmental awareness has spurred the extensive use of green materials in electronic applications, with bio-organic materials emerging as attractive alternatives to inorganic and organic materials due to their natural biocompatibility, biodegradability, and eco-friendliness. This study showcases the natural rubber based resistive switching memory devices and how varying sulphur concentrations (0 - 0.8 wt.%) in natural rubber thin films impact the resistive switching characteristics. The natural rubber was formulated and processed into a thin film deposited on an ITO substrate as the bottom electrode and with an Ag film as the top electrode. The addition of sulphur modifies the degree of crosslinking in the natural rubber thin film, from which the concentration of -C=C- group and density of defect site (S+) are affected, and hence the resistive switching behavior of the memory device. The devices exhibit bipolar resistance with symmetric switching characteristics which are attributed to the formation of conductive paths facilitate by electron transport along -C=C- and S+ defect sites between the two electrodes. Notably, a sample with 0.2 wt.% sulphur exhibits a high ON/OFF ratio (104), a large memory window (5.5 V), prolonged data retention (10 years), and reliable endurance (120 cycles). These findings highlight the potential of natural rubber as a promising material for eco-friendly resistive-switching random access memory applications.&#xD.

Specific and Polyfunctional T Cell Response Against N-Methyl-d-aspartate Receptor in an Autoantibody-Mediated Encephalitis Model

Background: Anti-N-Methyl-d-aspartate receptor (NMDAR) autoimmune encephalitis (NMDAR AE) is an autoimmune disease characterized by severe psychiatric and neurological symptoms. While the pathogenic role of antibodies (Abs) directed against the GluN1 subunit of NMDAR is well described in this disease, the immune mechanisms involved in the generation of the autoimmune B cell response, especially the role of T helper cells, are poorly understood. Previously, we developed a B-cell-mediated mouse model of NMDAR AE by immunization with a GluN1359–378 peptide that drives a series of symptoms that recapitulate AE such as anxiety behaviour and spatial memory impairment. Results: In this mouse model, we identified anti-GluN1-specific CD4+ but also CD8+ T cells in both spleen and meninges. T helper cells have a polyfunctional profile, arguing for a T and B cell crosstalk to generate anti-GluN1 pathogenic Abs. Interestingly, proteomic analysis of AE meninges showed enrichment of differentially expressed proteins in biological processes associated with B cell activation and cytokine signalling pathways. Conclusions: This study identified, for the first time, a potential contribution of T helper cells in the pathology of NMDAR AE and paved the way for the development of future tolerogenic approaches to treat relapses.

Shape Memory Polymer Foam Based on Nanofibrillar Composites of Polylactide/Polyamide

This paper presents the novel development of a shape memory polymer foam based on polymer–polymer nanocomposites. Herein, polylactide (PLA)/biosourced polyamide (PA) foams are fabricated by in situ fibrillation of polymer blends and a subsequent supercritical CO2 foaming technique. In this system, PLA serves as a shape memory polymer to endow this foam with a shape memory effect (SME), and in situ generated PA nanofibers are employed to reinforce the PLA cell walls and provide an additional permanent phase. A concentration of PA, 5 wt.%, was chosen to form an entangled nanofibrillar network. Foams of PLA/PA nanoblends with the same content of constituents were fabricated to reveal the effect of minor phase morphology on the cell structure and shape memory behavior of polymer foams. Profiting from the reinforcing effect of PA nanofibers, the PLA/PA nanocomposite foam exhibits smaller foam cells, a narrower cell size distribution and a comparable cell concentration than the PLA/PA nanoblend foam. In addition, PA nanofibers, unlike PA nanodroplets, favor the shape fixation ratio and recovery ratio and shorten the shape recovery time.

SuFEx‐based Transparent Polysulfates and their Applications in Tunable Resistant Electrical Memory Materials

AbstractVisibly transparent electron devices are current research highlights, which are found at the “neotype” stage of technical development for the usage in the next generation “see‐through” electronic devices. However, less attention is paid to transparent semiconductor memory devices, and hence, achieving such “see‐through” electronic devices are still partially limited by lacking the easily achievable and cost‐effective transparent memory materials. Herein, three visible light transparent polysulfate‐based memory devices are reported, e.g. ITO/P‐BPS/Al, ITO/P‐TPA/Al, and ITO/P‐TPABPS/Al, that displayed DRAM, WORM, and FLASH effects, respectively. The mechanisms of the observed memory behavior of each memory material are proposed on the basis of computational simulation. Remarkably, these polysulfates‐based memory materials are obtained by simply using different main‐chain repeating units, suggesting a wide application potential of polysulfate as functionalized materials.

Near-infrared light stimulation regulates neural oscillation and memory behavior of mice with Alzheimer’s disease

Photobiomodulation (PBM) is a non-invasive neuromodulation technique for the brain. Low-intensity near-infrared light (1–500 mw) has demonstrated the ability to improve memory in Alzheimer’s disease (AD) model mice, suggesting its potential for AD treatment. However, the impact of PBM on neural oscillations in the hippocampal region affected by AD remains unknown. In this study, AD model mice were subjected to PBM for 60 days and then tested using novel object recognition behavior (NOR) experiments. During behavioral experiments, local field potential signals (LFP) of the mice was recorded using a single electrode in the CA1 region to analyze memory ability and neural oscillation characteristics. The results revealed that mice stimulated with PBM exhibited significantly higher new object differentiation indices compared to the Sham group (p < 0.01). Furthermore, PBM stimulation led to a significant increase in relative power and sample entropy of theta and gamma bands (p < 0.01). The coupling intensities of θ-low-γ and θ-high-γ were also significantly higher in the PBM group compared to the Sham group (p < 0.01). In conclusion, these findings suggest that PBM may improve memory ability in AD mice through regulation of neural oscillation characteristics, providing a theoretical basis for utilizing PBM as a treatment modality for Alzheimer’s disease.

Chemical and Resistive Switching Properties of Elaeodendron buchananii Extract-Carboxymethyl Cellulose Composite: A Potential Active Layer for Biodegradable Memory Devices.

Biodegradable electronic devices play a crucial role in addressing the escalating issue of electronic waste accumulation, which poses significant environmental threats. In this study, we explore the utilization of a methanol-based extract of the Elaeodendron buchananii plant blended with a carboxymethyl cellulose biopolymer to produce a biodegradable and environmentally friendly functional material for a resistive switching memory system using silver and tungsten electrodes. Our analyses revealed that these two materials chemically interact to generate a perfect composite with near semiconducting optical bandgap (4.01 eV). The resultant device exhibits O-type memory behavior, with a low ON/OFF ratio, strong endurance (≥103 write/erase cycles), and satisfactory (≥103) data retention. Furthermore, through a comprehensive transport mechanism analysis, we observed the formation of traps in the composite that significantly improved conduction in the device. In addition, we established that altering the voltage amplitude modifies the concentration of traps, leading to voltage amplitude-driven multiple resistance states. Overall, our findings underscore the potential of functionalizing polymers that can be functionalized by incorporating plant extracts, resulting in biodegradable and nonvolatile memory devices with promising performance metrics.

Microstructure, mechanical properties, and shape memory behavior of laser-directed energy deposited Co–20Fe–18Cr–19Mn high-entropy alloy

Laser additive manufacturing has become a powerful tool in modern production processes, and the additive manufacturing of Cantor-type high-entropy alloys has attracted considerable attention owing to its unique properties. In this study, we successfully utilized a laser-directed energy deposition (L-DED) process to fabricate a Co–20Fe–18Cr–19Mn, wt.% (Co40Fe20Cr20Mn20, at.%) alloy and analyzed its microstructure, room temperature mechanical properties, and shape memory effect. Microstructural analysis revealed a dense microstructure of the alloy. Before heat treatment, the alloy exhibited a microstructure consisting of both columnar and equiaxed dendrites with a hexagonal close-packed structure (HCP). However, post-treatment led to a completely different microstructure owing to recrystallization with a face-centered cubic (FCC) structure. Tensile testing results indicated a subtle anisotropy in the yielding, and after heat treatment, a significant enhancement in ductility was observed. A study of the shape memory effect demonstrated that the as-printed samples exhibited an FCC-HCP dual-phase structure, which transformed into an FCC single-phase structure after heat treatment. The application of external loading induced reformation of the HCP phase, successfully demonstrating the shape memory effect in the alloy, with a maximum recovery strain of 0.79 %.

The effect of rubber and plastic mass ratio on the compatibilized ethylene propylene diene monomer/polypropylene TPV with shape memory behavior

AbstractThermoplastic vulcanizate (TPV) with shape memory performance showed great application potential in various fields. In this work, the effect of the mass ratio of ethylene propylene diene monomer (EPDM) and polypropylene (PP) on the performance of TPV with sea island microstructure compatibilized by magnesium maleate (MgMA) and maleic anhydride (MAH) was studied. The compatibilized TPV 70/30 and TPV 60/40 obtained good shape memory property with the shape fixity ratio (Rf) and shape recovery ratio (Rr) of 87.3%, 96.7% and 91%, 86.6% respectively. Rf increased with more PP content and decreased with more EPDM content, however Rr decreased with more PP content and increased with more EPDM content. The maximum Rf of 95.4% and the maximum Rr of 100% of TPV were obtained at the EPDM/PP mass ratio of 20/80 and 80/20 respectively. The tensile strength and elongation at break of TPV increased with more PP content in the blend. The result of DMA, Fourier transform infrared (FTIR), and SEM demonstrated the compatibility effect of MgMA and MAH on EPDM and PP interface.

Use of self-referencing memory strategies change over time with acculturation

Although cross-cultural research identifies cognitive differences when comparing across individuals, few studies have examined how acculturation, or cultural change over time within individuals, affects cognition. To address this gap, we investigated how acculturation and change in self-construal for Chinese students in the US impacts the self-reference effect in memory over two timepoints. Participants completed a self-referencing memory task and a set of questionnaires assessing acculturation orientation and self-construal over two time points, on average 16 months apart. As individuals' orientation towards host culture and independence increased over the two time points, they exhibited a larger self-reference effect (self vs. other) in memory and a smaller other-reference (other vs. control) effect. These patterns indicated that as Chinese students became more acculturated to US culture, they exhibited more US-like patterns of behavior in memory. In contrast, between-participant variability in acculturation orientation and independence were not related to self- or other-referencing.

The Infralimbic, but not the Prelimbic Cortex is needed for a Complex Olfactory Memory Task.

The medial prefrontal cortex (mPFC) plays a key role in memory and behavioral flexibility, and a growing body of evidence suggests that the prelimbic (PL) and infralimbic (IL) subregions contribute differently to these processes. Studies of fear conditioning and goal-directed learning suggest that the PL promotes behavioral responses and memory retrieval, while the IL inhibits them. Other studies have shown that the mPFC is engaged under conditions of high interference. This raises the possibility that the PL and IL play differing roles in resolving interference. To examine this, we first used chemogenetics (DREADDs) to suppress mPFC neuronal activity and tested subjects on a conditional discrimination task known to be sensitive to muscimol inactivation. After confirming the effectiveness of the DREADD procedures, we conducted a second experiment to examine the PL and IL roles in a high interference memory task. We trained rats on two consecutive sets of conflicting odor discrimination problems, A and B, followed by test sessions involving a mid-session switch between the problem sets. Controls repeatedly performed worse on Set A, suggesting that learning Set B inhibited the rats' ability to retrieve Set A memories (i.e. retroactive interference). PL inactivation rats performed similarly to controls. However, IL inactivation rats did not show this effect, suggesting that the IL plays a critical role in suppressing the retrieval of previously acquired memories that may interfere with retrieval of more recent memories. These results suggest that the IL plays a critical role in memory control processes needed for resolving interference.

Embryonic 6:2 Fluorotelomer Alcohol Exposure Disrupts the Blood‒Brain Barrier by Causing Endothelial‒to‒Mesenchymal Transition in the Male Mice.

6:2 Fluorotelomer alcohol (6:2 FTOH) is a raw material used in the manufacture of short-chain poly- and perfluoroalkyl substances. Our previous study revealed that gestational exposure to 6:2 FTOH can impair blood‒brain barrier (BBB) function in offspring, accompanied by anxiety-like behavior and learning memory deficits. The aim of this study was to further investigate the specific mechanism by which maternal exposure to 6:2 FTOH resulted in impaired BBB function in offspring mice. Pregnant mice were orally administered different doses of 6:2 FTOH (0, 5, 25, and 125mg/kg/day) from gestation day 8.5 until delivery. These results confirmed that maternal 6:2 FTOH exposure impaired BBB function and disrupted the brain immune microenvironment. Subsequent investigations revealed that endothelial-to-mesenchymal transition (EndMT) in the cerebral microvascular endothelium of offspring may be the mechanism mediating functional disruption of the BBB. Mechanistic studies revealed that exposure to 6:2 FTOH upregulated ETS proto-oncogene 1 (ETS1) expression via the tumor necrosis factor-α/extracellular signal-regulated kinase 1/2 signaling pathway, which mediated disturbances in energy metabolism, leading to impaired actin dynamics and subsequently triggering the EndMT phenotype. This is the first finding indicating that gestational 6:2 FTOH exposure caused functional impairment of the BBB through ETS1-mediated EndMT in cerebral microvascular endothelial cells, potentially providing novel insight into the environmental origins of neurodevelopmental disorders.

Disrupted Hippocampal-Prefrontal Networks in a Rat Model of Fragile X Syndrome: A Study Linking Neural Dynamics to Autism-Like Behavioral Impairments.

FMR-KO and control rats underwent a battery of behavioral tests assessing sociability, memory, and anxiety. Single-unit electrophysiology recordings were then conducted to measure patterns of neural activity in H-PFC circuit. Advanced mathematical models were used to characterize the patterns that were then compared between groups using generalized linear mixed models. FMR-KO rats demonstrated significant behavioral deficits in sociability, spatial learning, and anxiety, aligning with symptoms of ASD. At the neural level, these rats exhibited abnormal firing patterns in the H-PFC circuit that is critical for learning, memory, and social behavior. The neural networks in FMR-KO rats were also less densely connected and more fragmented, particularly in hippocampal-PFC correlated firing. These findings suggest that disruptions in neural network dynamics underlie the observed behavioral impairments in FMR-KO rats. FMR-KO significantly disrupts several characteristics of action potential firing in the H-PFC network, leading to deficits in social behavior, memory, and anxiety, as seen in FXS. This disruption is characterized by less organized and less resilient hippocampal-PFC networks. These findings suggest that therapeutic strategies aimed at normalizing neural dynamics, such as with brain stimulation, could potentially improve behavior and cognitive functions in autistic individuals. Fragile X Syndrome is associated with autism, cognitive challenges and anxietyThe loss of Fmr1 protein disrupts processes involved in building neural networksThe consequence is abnormal neural dynamics in hippocampal-prefrontal cortex networksNormalization of dynamics could improve outcomes in FXS and ASD.

Hippocampal Nogo66-NgR1 signaling activation restricts postsynaptic assembly in aged mice with postoperative neurocognitive disorders.

Postoperative neurocognitive disorders (pNCD) are a common neurological complication, especially in elderly following anesthesia and surgery. Yet, the underlying mechanisms of pNCD remain elusive. This study aimed to investigate the molecular mechanisms that compromise synaptic metaplasticity in pNCD development with a focus on the involvement of Nogo-66 receptor 1 (NgR1) in the pathogenesis of pNCD in aged mice. Aged mice subjected to anesthesia and laparotomy surgery exhibited anxiety-like behavior and contextual fear memory impairment. Moreover, the procedure significantly increased NogoA and NgR1 expressions, particularly in the hippocampal CA1 and CA3 regions. This increase led to the depolymerization of F-actin, attributed to the activation of the RhoA-GTPase, resulting in a reduction of dendritic spines and changes in their morphology. Additionally, these changes hindered the efficient postsynaptic delivery of the subunit GluA1 and GluA2 of AMPA receptors (AMPARs), consequently diminishing excitatory neurotransmission in the hippocampus. Importantly, administering the competitive NgR1 antagonist peptide NEP1-40 (Nogo-A extracellular peptide residues 1-40 amino acids of Nogo-66) and Fasudil (a Rho-kinase inhibitor) effectively mitigated synaptic impairments and reversed neurocognitive deficits in aged mice following anesthesia and surgery. Our work indicates that high hippocampal Nogo66-NgR1 signaling disrupts postsynaptic AMPA receptor surface delivery due to F-actin depolymerization in the pathophysiology of pNCD.

Developmental Syngap1 haploinsufficiency in medial ganglionic eminence-derived interneurons impairs auditory cortex activity, social behavior and extinction of fear memory.

Mutations in SYNGAP1, a protein enriched at glutamatergic synapses, cause intellectual disability associated with epilepsy, autism spectrum disorder and sensory dysfunctions. Several studies showed that Syngap1 regulates the time course of forebrain glutamatergic synapse maturation; however, the developmental role of Syngap1 in inhibitory GABAergic neurons is less clear. GABAergic neurons can be classified into different subtypes based on their morphology, connectivity and physiological properties. Whether Syngap1 expression specifically in Parvalbumin (PV) and Somatostatin (SST)-expressing interneurons, which are derived from the medial ganglionic eminence, plays a role in the emergence of distinct brain functions remains largely unknown. We used genetic strategies to generate Syngap1 haploinsufficiency in a) prenatal interneurons derived from the medial ganglionic eminence, b) in postnatal PV cells and c) in prenatal SST interneurons. We further performed in vivo recordings and behavioral assays to test whether and how these different genetic manipulations alter brain function and behavior in mice of either sex.Mice with prenatal-onset Syngap1 haploinsufficiency restricted to Nkx2.1-expressing neurons show abnormal cortical oscillations and increased entrainment induced by 40Hz auditory stimulation, but lack of stimulus-specific adaptation. This latter phenotype was reproduced in mice with Syngap1 haploinsufficiency restricted to PV, but not SST, interneurons. Prenatal-onset Syngap1 haploinsufficiency in Nkx2.1-expressing neurons led to impaired social behavior and inability to extinguish fear memories; however, neither postnatal PV- nor prenatal SST-specific mutant mice show these phenotypes. We speculate that Syngap1 haploinsufficiency in prenatal/perinatal PV interneurons may contribute to cortical activity and cognitive alterations associated with Syngap1 mutations.Significance statement Mutations in the human gene cause a form of developmental epileptic encephalopathy associated with intellectual disability, autism and sensory dysfunctions. Several studies have shown that in addition to playing a major role in the synaptic maturation and plasticity of forebrain excitatory neurons, Syngap1 affects GABAergic circuit function as well. Forebrain GABAergic neurons can be divided into different subtypes. Whether Syngap1 expression specifically in distinct interneuron populations and during specific developmental time windows plays a role in the emergence of distinct brain functions remains largely unknown. Here, we report that early, pre or perinatal Syngap1 expression in developing GABAergic neurons derived from the medial ganglionic eminence promotes the development of auditory cortex function, social behavior and ability to extinguish fear memories.

Pyrazolone-nicotinic acid derivative (4Z)-4-(2-hydroxybenzylidine)-5-methyl-2-(pyridine-3-ylcarbonyl)-2, 4-dihydro-3H-pyrazole-3-one (IIc) as multitarget inhibitor of neurodegeneration and behavioural impairment in Dementia.

The study was aimed at the synthesis and pharmacological investigation of (4Z)-4-(2-hydroxybenzylidine)-5-methyl-2-(pyridine-3-ylcarbonyl)-2, 4-dihydro-3H-pyrazole-3-one (IIc) in mice model of scopolamine-induced neurodegeneration and cognition impairment. The behavioural studies included Y-Maze Test, Water Morris Test, and Novel Object Recognition Test in Albino mice (20-25g). Scopalamine was used as an inducing agent. The acetylcholinesterase (AChE) inhibitory assay was used to assess the role of the test compounds in vitro. The Crystal Violet Staining (Nissl staining) was used to assess the neuroprotective and antiapoptotic effect through quantifying the number of neurons and viability. The expression of the anti-inflammatory enzyme cyclooxygenase-2 (COX-2), cytokine tumour necrotic factor (TNF-α), key transcription factor producing pro-inflammatory signals nuclear factor kappa B (P-NFkB), and apoptosis marker p-JNK was validated through enzyme-linked immunosorbent assay (ELISA) and immunohistochemical (IHC) analysis. The tested compound reverted cognitive and behavioural impairment through inhibiting scopolamine-induced inflammation and oxidative stress. We found that the compound IIc improved the short-term memory and learning behaviour of the experimental animals. Further investigation into molecular mechanisms showed that this effect was the manifestation of immunomodulatory, antioxidant, and consequently, of downsizing of inflammatory cytokines. These results were further validated through docking analysis. Finally, we conclude that the pyrazolone-nicotinic acid derivative IIc reversed the scopolamine-induced cognitive and behavioural deficits, attributed to acetylcholinesterase inhibition, neuronal recovery, antioxidant potential, and through downregulating the neuroinflammatory mediators p-NF-kB, cytokine TNF-α, and anti-inflammatory enzyme COX-2.

4D Printing of Multifunctional and Biodegradable PLA-PBAT-Fe3O4 Nanocomposites with Supreme Mechanical and Shape Memory Properties.

4D printing magneto-responsive shape memory polymers (SMPs) using biodegradable nanocomposites can overcome their low toughness and thermal resistance, and produce smart materials that can be controlled remotely without contact. This study presented the development of 3D/4D printable nanocomposites based on poly (lactic acid) (PLA)-poly (butylene adipate-co-terephthalate) (PBAT) blends and magnetite (Fe3O4) nanoparticles. The nanocomposites are prepared by melt mixing PLA-PBAT blends with different Fe3O4 contents (10, 15, and 20 wt%) and extruded into granules for material extrusion 3D printing. The morphology, dynamic mechanical thermal analysis (DMTA), mechanical properties, and shape memory behavior of the nanocomposites are investigated. The results indicated that the Fe3O4 nanoparticles are preferentially distributed in the PBAT phases, enhancing the storage modulus, thermal stability, strength, elongation, toughness, shape fixity, and recovery of the nanocomposites. The optimal Fe3O4 loading is found to be 10 wt%, as higher loadings led to nanoparticle agglomeration and reduced performance. The nanocomposites also exhibited fast shape memory response under thermal and magnetic activation due to the presence of Fe3O4 nanoparticles. The 3D/4D printable nanocomposites demonstrated multifunctional multi-trigger shape-memory capabilities and potential applications in contactless and safe actuation.

A Programmable 2D/3D Anti‐Counterfeiting System via Shape Memory Polymer with Surface Wrinkle and Fluorescence

AbstractThe issue of counterfeiting has always been a major challenge in today's society, putting forward high requirements for anti‐counterfeiting technology. Here, a promising 2D/3D anti‐counterfeiting security system is developed based on anthracene‐functionalized poly(styrene‐butadiene‐styrene) (SBS‐CAN), which possessed the physical unclonable self‐wrinkling patterns, fluorescence, and shape memory behavior. By controlling the dimerization of anthracene groups with ultraviolet light and external pre‐stretched operation, 2D information with surface wrinkle and fluorescence is achieved, allowing for the design of security systems based on actual needs. Furthermore, 3D structures constructed based on the shape memory behavior can further be utilized to encrypt these 2D information, enhancing the security level and weakening the cloneable risk of surface wrinkle and fluorescence for further. This programmable 2D/3D anti‐counterfeiting system has multiple advantages over the commonly used fluorescent wrinkled tag or fluorescent shape memory label, providing an intelligent choice for high‐security information carriers.

Influence of Gamma irradiation on shape memory polymer nano-composite for satellite deployment mechanism

This research investigates the impact of gamma irradiation on epoxy-MWCNT nanocomposites for satellite deployment mechanisms. Nanocomposites, enhanced with surfactants, were meticulously prepared and subjected to controlled gamma irradiation (250–1000 kGy) utilizing the Cobalt-60 facility Industrial Mega Gamma-1 at NCRRT in Egypt. Surface tension measurements explored surfactant effects on epoxy-MWCNT composites in acetone. Acetone reduced tension from 26.7 to be 24.2 (mN/m). Surfactants (Tween 80, SDS) effectively lowered tension (24.4 mN/m), while surfactant-free systems had higher tension (25.1 mN/m). Cationic surfactant (CTAB) slightly increased tension (25.4 mN/m) but aided MWCNT dispersion. Nonionic and anionic surfactants showed superior dispersing power, aligning with MWCNTs and enhancing dispersion. Thermogravimetric analysis (TGA) unveiled alterations in the thermal stability of epoxy-MWCNT nanocomposites induced by radiation, particularly evident at elevated doses (500 and 1000 kGy). Notably, surfactant-modified specimens exhibited discernible effects on various thermal stability parameters. DMA analysis revealed radiation-induced changes in viscoelastic properties. Unirradiated epoxy exhibited a Tg of 58 °C, while 250 kGy irradiation enhanced crosslinking (Tg: 64 °C). Higher doses (500 kGy, 1000 kGy) caused marginal Tg changes. Surfactant-modified samples showed varied effects, with Tween 80 emphasizing its role in phase separation. Results highlighted radiation’s influence on stiffness and energy dissipation. Shape memory behavior indicated increased recovery time with higher doses, except at 250 kGy. Epoxy-MWCNT exhibited a stable recovery time, suggesting a MWCNT stabilizing effect. Fixation rates consistently reached 100%, indicating improved shape recovery influenced by MWCNTs and surfactants. This study provides insights into optimizing nanocomposites for satellite deployment applications.

Administration of Young Coconut (Cocos nucifera L.) Juice Ameliorates Memory Impairment in a Menopausal Rat Model.

In Southeast Asia, the traditional use of young coconut (Cocos nucifera L.) juice (YCJ) by women to alleviate postmenopausal symptoms suggests potential estrogenic properties. However, few studies explore the impact of YCJ on pathologies associated with estrogen deficiency in postmenopausal animal models. This study examines the impact of YCJ supplementation on memory impairment and depression-like behavior in ovariectomized (Ovx) rats. Ten-week-old female rats underwent either a sham operation (Sham) or bilateral Ovx. The rats in the Ovx + YCJ group received 5×-concentrated YCJ by gavage at a dose of 15 mL/kg body weight. Twelve weeks later, the Morris water maze and forced swim tests were used to evaluate hippocampus-dependent spatial memory and depression-like behavior, respectively. The Ovx rats displayed significant memory impairment (p < 0.05) and depression-like behaviors (p < 0.05), while the memory performance in the rats in the Ovx + YCJ group resembled that of the Sham rats. However, the administration of YCJ did not result in the improvement of depression-like behavior. These findings suggest that YCJ consumption may help ameliorate memory impairment in postmenopausal women.