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#39507502   2024/07/11 To Up

Selecting optimal wearables for measuring physiological arousal in robot-delivered mindfulness-based exercises.

While social robots show promise for therapeutic interventions, accurate assessments of (vulnerable) participants' affective outcomes require attention. The careful selection of devices for recording autonomic processes in response to stress-inducing and relaxing exercises is essential to ensure data quality recordings and participants' comfort. This foundational study assessed two commonly utilized devices to record electrodermal activity (EDA), indexed through skin conductance, concerning their sensitivity to stress-relaxation manipulations and social validity during a robot intervention: a sock with a Shimmer device and a wrist-worn Empatica E4. We aimed to select the most sensitive and easy-to-wear one as a precursor to a larger intervention study featuring mindfulness-based relaxation exercises delivered by an NAO robot. The findings, based on 28 healthy Dutch-speaking adult volunteers wearing both devices, revealed sensitivity in detecting EDA variations in arousal following stressful (increase) and Robot-delivered mindfulness-based relaxation (decrease) exercises, further corroborated by self-reports. Bland-Altman results suggested little agreement between the two devices and lower sensitivity for the Empatica E4. No statistically significant differences concerning wearing comfort between the Empatica E4 and the Shimmer devices emerged. Although both devices independently showed sensitivity to stress/relaxation manipulation, the choice for one or the other should be informed by the activities in the intervention.
Stefania V Vacaru, Lok-Pui Lau, Kyra Frederiks, Paula S Sterkenburg, Emilia Barakova

1101 related Products with: Selecting optimal wearables for measuring physiological arousal in robot-delivered mindfulness-based exercises.

1 G 5 G500 MG250 mg 100 G 1 G100 μg1 Set

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#39507303   2023/11/03 To Up

Copper-catalyzed generation of nitrogen-centered radicals and reactions thereof.

Nitrogen-centered radicals are reactive intermediates that can function in the formation of new C-N bonds or enable the formation of other bonds through their ability to abstract hydrogen atoms to generate carbon radical intermediates. Methods for the generation of nitrogen-centered radicals have traditionally involved application of radical initiators and propagators such as peroxides, AIBN and tin hydrides. More recently, approaches to nitrogen-centered radicals involving copper catalysis have been developed. In the transformations summarized herein, the copper catalyst either oxidizes or reduces the nitrogen-centered radical precursor. Some of these methods have been developed as catalytic enantioselective using chiral copper complexes.
Sherry R Chemler

2552 related Products with: Copper-catalyzed generation of nitrogen-centered radicals and reactions thereof.

1000 Reactions100 reactions25 mg4X1.25ml; 200 reactions (250100 reactions 5 G 1 kit(s) 25 reactions200

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#39507283   2024/10/23 To Up

The evolution of psychotherapy: from Freud to prescription digital therapeutics.

The evolution of psychotherapeutic treatments from Freud to digitally administered evidence-based treatments reflects a history of progressive advance. This history is characterized by identification of problems with the current state of the art, followed by solutions inspired and supported by advances in basic science and technology leading to subsequent recognition of other limitations revealed by the new advance. The common thread running through this process is (a) increasing specificity of the psychotherapeutic interventions, (b) increasing evidence of efficacy and safety, (c) increasing integrity and reliability in the delivery of the intervention, (d) increased equality of access, and (e) recognition of the need for regulation to provide protection for the public from unsafe or ineffective products. This evolution of psychotherapeutic treatments, not surprisingly, has been foreshadowed by the precursor history of the evolution of pharmacologic treatment. Although intellectual history is lumpy and does not sort itself into discrete and coherent epochs, such sorting is a useful heuristic for describing the advance of medicine and the therapeutic enterprise. This paper will discuss six successive epochs of psychotherapy. For each it will discuss the problem of the preceding era it sought to solve, the advance it brought to the field, the emerging science and technology that supported that advance, and the precursor development in pharmacological treatments that foreshadowed that epoch of psychotherapy. Finally, it will conclude with some observations about the proximate future.
John P Docherty, Brett M Colbert

1532 related Products with: The evolution of psychotherapy: from Freud to prescription digital therapeutics.

1.00 flask1 kit(96 Wells)21 mL1 module100 μg

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#39506954   2024/10/11 To Up

Nitrogen functionalized biomass derived mesoporous carbon nanomaterials for electrochemical detection of lead (II) ions.

This study has explored the sustainable solution after designing an economical metal-free biomass-derived nanocarbon for the selective sensing of lead. The nitrogen and sulfur-rich mesoporous nanocarbon is designed through a facile hydrothermal-assisted thermal annealing method. The high-temperature treatment gave nanocarbon unique carbon dot decorated layered morphology, while nitrogen and sulfur precursor thiourea and melamine strengthened the nanomaterial stability, sensitivity, and selectivity toward lead metal ions. The high specific surface area of mesoporous nanocarbon viz., 1671.93 m/g with the pore width and pore volume of 2.02 nm and 0.476 cm/g has enhanced the conductivity of as-synthesized sensor, which helps in increasing sensitivity toward lead. The high conductivity was also confirmed through cyclic voltammetry, where an 80 % increment in current was observed in the case of the modified electrode when compared with bare GCE. The differential pulse normal voltammetry and differential pulse anodic stripping voltammetry were performed to calculate the detection limit, where an excellent detection limit of 22 nM was obtained from the DPASV technique. Moreover, the nanomaterial was also tested for detecting lead in tap water. The as-synthesized nanocomposite is highly efficient and selective for the detection of lead. This study will motivate the researchers to engineer sustainable and efficient devices for sensing metal pollutants.
Ritika Sharma, Dharmender Singh Rana, Abhishek Awasthi, Dilbag Singh, Ahmed A Ibrahim, Ahmad Umar, Sotirios Baskoutas

2450 related Products with: Nitrogen functionalized biomass derived mesoporous carbon nanomaterials for electrochemical detection of lead (II) ions.

2 x 96 well plate2x96 well plate250 mg 1000 ml 10 mg 100 G 1 G10x96 well plates

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#39506939   2024/10/18 To Up

75 years of forensic profiling: A critical review.

The interest in characterization of drugs abused started in 1948 with the aim of determining the origin of opium. After 75 years there is still a great interest in this approach, called geo-profiling, chemical or forensic profiling in the following decades. Recently chemical attribution signatures (CAS) were proposed by the authors who studied "synthesis precursors and byproducts, impurities, degradation products, and metabolites in various biological matrices" of fentanyl. Forensic profiling evolved during these decades: new analytical approaches were tested and it was applied to more and more products, which threaten the health and security of citizens worldwide. In substances of natural origins (e.g. opium, cannabis and cocaine), it is possible to exploit the great variability of both elements and organic chemical compounds and to study chemical compounds such as reagents and solvents, by-products, and cutting agents used in the production chain. Profiles can be used to classify products from different seizures into groups of similar samples (tactical intelligence) or to determine the origin of samples (strategic intelligence). Chromatographic approaches coupled to mass spectrometry are very common to determine organic profiles, while elemental profiles are obtained by nuclear activation analysis, inductively coupled plasma mass spectrometry or ion beam analysis. A very important role in the field is played by isotope ratio analysis. Approaches to obtain forensic profiles are available also for chemical warfare agents, explosives, illegal medicines, doping agents, supplements, food. Chemometrics can be particularly useful to establish the authenticity of products and for the interpretation of large amount of forensic data. The future of forensic profiling is a challenge for forensic sciences. Organized crime is involved in the manufacturing of a large number of illegal products and forensic profiling is a very powerful tool to support the health of citizens and the administration of justice worldwide.
Roberta Tittarelli, Sara Dagoli, Rossana Cecchi, Luigi Tonino Marsella, Francesco Saverio Romolo

2855 related Products with: 75 years of forensic profiling: A critical review.

250 m Pcs Per Pack50 mg1 g50 ul250 m Pcs Per Pack 1KG1 mg6250 m Pcs Per Pack1 g1 mg50 ul

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#39506927   2024/11/07 To Up

Selective Protonation of Catalytic Dyad for γ-Secretase-Mediated Hydrolysis Revealed by Multiscale Simulations.

γ-Secretase plays a crucial role in producing disease-related amyloid-β proteins by cleaving the amyloid precursor protein (APP). The enzyme employs its catalytic dyad containing two aspartates (Asp257 and Asp385) to hydrolyze the substrate by a general acid-base catalytic mechanism, necessitating monoprotonation of the two aspartates for efficient hydrolysis. However, the precise protonation states of the aspartates remain uncertain. In this study, we employed a multiscale computational approach to investigate the dependence of the catalytic efficiency of γ-secretase on the protonation states of its catalytic dyad. Over 200 ms unbiased atomistic simulations of the substrate-enzyme complex reveal diverse orientations of the scissile bond of the bound substrate and accessible structural ensembles of the catalytic dyad with Asp257-Asp385 distances fluctuating between 4 and 10 Å. With a quantum mechanics/molecular mechanics (QM/MM) approach accelerated by enhanced sampling techniques, we find that the first step of the hydrolysis reaction, i.e., the formation of a gem-diol intermediate, experiences a higher reaction barrier by ∼2 kcal/mol when Asp385 is protonated. Furthermore, we find that Arg269 of the enzyme is most likely responsible for this preference of the protonation state: its basic side chain is spatially close to that of Asp257 and specifically stabilizes the transition state electrostatically when Asp257 is protonated. Collectively, our study suggests that Asp257 is likely the favored protonation site for APP cleavage by γ-secretase.
Bohua Wu, Shu Li, Wei Han

1325 related Products with: Selective Protonation of Catalytic Dyad for γ-Secretase-Mediated Hydrolysis Revealed by Multiscale Simulations.

100μg100 mg 500 ml 100 mg0.2 mg100μg1 mg250 mg96 Tests100μg10 mg

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#39506610   2024/11/07 To Up

OsbHLH6, a basic helix-loop-helix transcription factor, confers arsenic tolerance and root-to-shoot translocation in rice.

Arsenic (As) is extremely toxic to plants, posing a serious concern for food safety. Identification of genes responsive to As is significative for figuring out this issue. Here, we identified a bHLH transcription factor OsbHLH6 that was involved in mediating the processes of As tolerance, uptake, and root-to-shoot translocation in rice. The expression of OsbHLH6 gene was strongly induced after 3 and 48 h of arsenite [As(III)] treatment. The OsbHLH6-overexpressed transgenic rice (OE-OsbHLH6) was sensitive to, while the knockout mutant of OsbHLH6 gene (Osbhlh6) was tolerant to As(III) stress by affecting the contents of reactive oxygen species (ROS) and non-protein thiols (NPT), etc. Knockout of OsbHLH6 gene increased significantly the As concentration in roots, but decreased extensively As accumulation in shoots, compared to that in OE-OsbHLH6 and WT plants. The transcripts of phytochelatins (PCs) synthetase encoding genes OsPCS1 and OsPCS2, as well as As(III) transporter encoding genes OsLsi1 and OsABCC1 were greatly abundant in Osbhlh6 mutants than in OE-OsbHLH6 and WT plants under As(III) stress. In contrast, the expression of OsLsi2 gene was extensively suppressed by As(III) in Osbhlh6 mutants. OsbHLH6 acted as a transcriptional activator to bind directly to the promoter and regulate the expression of OsPrx2 gene that encodes a peroxidase precursor. Moreover, overexpression of OsbHLH6 gene resulted in significant change of expression of amounts of abiotic stress-related genes, which might partially contribute to the As sensitivity of OE-OsbHLH6 plants. These findings may broaden our understanding of the molecular mechanism of OsbHLH6-mediated As response in rice and provide novel useful genes for rice As stress-resistant breeding.
Menghan Huang, Yang Liu, Qianwen Bian, Wenjing Zhao, Juan Zhao, Qingpo Liu

2157 related Products with: OsbHLH6, a basic helix-loop-helix transcription factor, confers arsenic tolerance and root-to-shoot translocation in rice.

200ug100.00 ugKit100 ug 100ul100.00 ug 25UG100 ug20 100ul100.00 ug100 μg

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#39506526   2024/11/06 To Up

Impact of Tetrakis(dimethylamido)tin(IV) Degradation on Atomic Layer Deposition of Tin Oxide Films and Perovskite Solar Cells.

Tin oxide (SnO) films synthesized by atomic layer deposition (ALD) are widely explored in a range of optoelectronic devices including electrochemical sensors, transistors, and photovoltaics. However, the integrity of the key ALD-SnO precursor, namely tetrakis(dimethylamido)tin (IV) (TDMASn), and its influence on the properties of ultimate films remain unexplored. Here a significant degradation of TDMASn into bis(dimethylamido)tin(II) via the Sn-imine complex is reported, and its impact on the corresponding films and devices is examined. It is found, surprisingly, that this degradation does not affect the growth kinetics and morphology of ALD-SnO films. But it notably deteriorates their electronic properties, resulting in films with twice the electrical resistance due to different oxidation mechanisms of the degradation products. Perovskite solar cells employing such films exhibit a significant loss in power conversion efficiency, primarily due to charge transport and transfer losses. These findings urge strategies to stabilize TDMASn, a critical precursor for ALD-SnO films, or to identify alternative materials to achieve efficient and reliable devices.
Shuang Qiu, Augusto Amaro, Diana Fabulyak, Julien Appleby-Millette, Cassidy Conover, Dongyang Zhang, Vishal Yeddu, I Teng Cheong, Irina Paci, Makhsud I Saidaminov

1399 related Products with: Impact of Tetrakis(dimethylamido)tin(IV) Degradation on Atomic Layer Deposition of Tin Oxide Films and Perovskite Solar Cells.

5 G1.00 flask100.00 ug1 mg0.1ml (1mg/ml)100 mg10100100ul1.00 flask100ug10 mg

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#39506109   2024/11/06 To Up

Cellular ATP demand creates metabolically distinct subpopulations of mitochondria.

Mitochondria serve a crucial role in cell growth and proliferation by supporting both ATP synthesis and the production of macromolecular precursors. Whereas oxidative phosphorylation (OXPHOS) depends mainly on the oxidation of intermediates from the tricarboxylic acid cycle, the mitochondrial production of proline and ornithine relies on reductive synthesis. How these competing metabolic pathways take place in the same organelle is not clear. Here we show that when cellular dependence on OXPHOS increases, pyrroline-5-carboxylate synthase (P5CS)-the rate-limiting enzyme in the reductive synthesis of proline and ornithine-becomes sequestered in a subset of mitochondria that lack cristae and ATP synthase. This sequestration is driven by both the intrinsic ability of P5CS to form filaments and the mitochondrial fusion and fission cycle. Disruption of mitochondrial dynamics, by impeding mitofusin-mediated fusion or dynamin-like-protein-1-mediated fission, impairs the separation of P5CS-containing mitochondria from mitochondria that are enriched in cristae and ATP synthase. Failure to segregate these metabolic pathways through mitochondrial fusion and fission results in cells either sacrificing the capacity for OXPHOS while sustaining the reductive synthesis of proline, or foregoing proline synthesis while preserving adaptive OXPHOS. These findings provide evidence of the key role of mitochondrial fission and fusion in maintaining both oxidative and reductive biosyntheses in response to changing nutrient availability and bioenergetic demand.
Keun Woo Ryu, Tak Shun Fung, Daphne C Baker, Michelle Saoi, Jinsung Park, Christopher A Febres-Aldana, Rania G Aly, Ruobing Cui, Anurag Sharma, Yi Fu, Olivia L Jones, Xin Cai, H Amalia Pasolli, Justin R Cross, Charles M Rudin, Craig B Thompson

1626 related Products with: Cellular ATP demand creates metabolically distinct subpopulations of mitochondria.

1mg200ul100ug Lyophilized100 ul100ug Lyophilized100ul3x 500 ml100ug100ug Lyophilized25 assays 5 G 100 ul

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#39505850   2024/11/06 To Up

The third generation AKR1C3-activated prodrug, ACHM-025, eradicates disease in preclinical models of aggressive T-cell acute lymphoblastic leukemia.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy that expresses high levels of the enzyme aldo-keto reductase family 1 member C3 (AKR1C3). To exploit this finding, we developed a novel prodrug, ACHM-025, which is selectively activated by AKR1C3 to a nitrogen mustard DNA alkylating agent. We show that ACHM-025 has potent in vivo efficacy against T-ALL patient-derived xenografts (PDXs) and eradicated the disease in 7 PDXs. ACHM-025 was significantly more effective than cyclophosphamide both as a single agent and when used in combination with cytarabine/6-mercaptopurine. Notably, ACHM-025 in combination with nelarabine was curative when used to treat a chemoresistant T-ALL PDX in vivo. The in vivo efficacy of ACHM-025 directly correlated with AKR1C3 expression levels, providing a predictive biomarker for response. Together, our work provides strong preclinical evidence highlighting the potential of ACHM-025 as a targeted and effective therapy for aggressive forms of T-ALL.
Cara E Toscan, Hannah McCalmont, Amir Ashoorzadeh, Xiaojing Lin, Zhe Fu, Louise Doculara, Hansen J Kosasih, Roxanne Cadiz, Anthony Zhou, Sarah Williams, Kathryn Evans, Faezeh Khalili, Ruilin Cai, Kristy L Yeats, Andrew J Gifford, Russell Pickford, Chelsea Mayoh, Jinhan Xie, Michelle J Henderson, Toby N Trahair, Adam V Patterson, Jeff B Smaill, Charles E de Bock, Richard B Lock

2924 related Products with: The third generation AKR1C3-activated prodrug, ACHM-025, eradicates disease in preclinical models of aggressive T-cell acute lymphoblastic leukemia.

500 gm.1 mg1.00 flask3 inhibitors96 tests100 μg1x10e7 cells

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