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1.
Cureus ; 16(7): e63783, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39099900

RESUMEN

Background Hypertensive emergencies represent high-cardiovascular-risk situations defined by severe increases in blood pressure. The prevalence of hypertension in non-ST elevation myocardial infarction (NSTEMI) is higher compared to STEMI and there is a lack of studies on NSTEMI patients with hypertensive emergencies. Patients with diabetes exhibited a higher rate of hypertensive emergencies. This study's primary aim was to investigate the coronary artery disease profile in hypertensive emergency patients with NSTEMI, and the secondary aim was to determine the impact of diabetes on the development of hypertensive emergencies. Methodology A total of 100 patients with NSTEMI and hypertensive emergency presenting to the hospital were enrolled in the study. The duration of the study was 24 months. The patients were also sub-grouped into diabetic and nondiabetic. Baseline characteristics were noted, and coronary angiogram and renal angiogram were also done. Based on variables, the chi-square test and t-test were employed to assess the significance. P-value < 0.05 was considered statistically significant. Results The mean age at presentation for patients with NSTEMI and hypertensive emergency was 58 years. Patients consuming alcohol were slightly higher (28, 28%) than those who smoked (23, 23%). Among all, 48 (48%) patients had diabetes. When considering the number of vessels, diabetic patients had more single-vessel diseases (18, 37.5%) and nondiabetic patients had more double-vessel diseases (15, 28.8%). The mean ejection fraction of the diabetic group was 56.1% ± 6.8% and the nondiabetic group was 54.2% ± 7.7%. Among all the patients, 52 (62.6%) used combination drugs, while 39 (46.9%) were on defaulter drugs. Conclusions Several risk factors like age, smoking, alcohol, and nonadherence to drugs were found to have an association with the occurrence of hypertensive emergency. Diabetes was found to be significantly associated with unfavorable coronary anatomy among the population.

2.
Sci Rep ; 14(1): 17865, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090346

RESUMEN

Hydrocarbon fuels contain approximately 50 times more energy per unit mass than commercial batteries, thus converting even 10% of the energy contained in hydrocarbon fuels to electrical energy could present a more mass-efficient electrical energy source than batteries. Considering the storability of hydrocarbon fuels compared to hydrogen, the viability of direct hydrocarbon polymer electrolyte membrane fuel cells was examined. With extremely pure (> 99.99%) propane, the cell Open-Circuit Voltage (OCV) was only 0.05 V and produced negligible power. However, with addition of trace quantities of unsaturated hydrocarbons, the cell had an OCV of 0.85 V and produced power, even after the unsaturated hydrocarbon addition was discontinued. At sufficiently high current densities, power output gradually decreased then the cell rapidly "extinguished" but by periodically shutting off the current for short time intervals the average power density could be increased significantly. Chemical analysis revealed that no significant amounts of hydrocarbon intermediates or CO were present in the effluent and that conversion of the hydrocarbon fuel to CO2 and H2O was nearly complete. An analytical model incorporating the relative rates of conversion of active anode catalyst sites to inactive sites and vice versa was developed to interpret this behavior. The model predictions were consistent with the experimental observations; possible physical mechanisms are discussed.

3.
J Am Chem Soc ; 146(33): 23205-23211, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39120574

RESUMEN

Two-dimensional inorganic-organic hybrid perovskites are in the limelight due to their potential applications in photonics and optoelectronics. They are environmentally stable, and their various chemical compositions offer a wide range of bandgap energies. Alternatively, crystal deformation enables in situ control over their optical properties. Here, we investigate (C6H9C2H4NH3)2PbI4, a hybrid perovskite whose organic linkers are 2-(1-cyclohexenyl)ethylammonium. Pressure-dependent optical absorption and emission spectroscopy reveal a hysteretic piezochromism that was not reported for other lead iodide-based 2D perovskites. We combine our optical studies with high-pressure X-ray diffraction experiments and first-principles calculations to demonstrate that the deformation of the inorganic lead iodide layers is the main reason for the observed changes in the optical bandgap.

4.
Cureus ; 16(7): e65466, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39188425

RESUMEN

Background The COVID-19 pandemic has introduced unprecedented challenges to global healthcare systems, including heightened psychological stress among patients. This study evaluates the preoperative anxiety levels among patients scheduled for surgery during the COVID-19 pandemic. Methods This cross-sectional observational study was conducted between April 2020 and March 2022. Adult patients aged 18-80 years, scheduled for elective or emergency surgery, were included. Exclusion criteria were mental illness, impaired communication, and hemodynamic instability. A pre-validated questionnaire addressing demographics, prior surgery exposure, surgery-related anxiety, and COVID-19-related fears was administered. Anxiety levels were scored on a 1-5 Likert scale. Data were analyzed using SPSS version 22 (IBM Corp., Armonk, USA). Results A total of 112 patients participated, with a mean age of 42.3±14.2 years. The majority were female (61 patients, 54.5%), married (96 patients, 85.7%), and resided in urban areas (85 patients, 75.9%). Most patients had no prior surgical history (87 patients, 77.7%). Surgery-related fears were prevalent, with 110 patients (98.2%) fearing surgical complications and 111 patients (99.1%) fearing postoperative pain. COVID-19-related fears were also significant, with 108 patients (96.4%) fearing infection during hospital stay and 100 patients (89.3%) fearing infecting family members. Mild fear was the most common anxiety level (70 patients, 62.95%), followed by moderate fear (25 patients, 22.5%). Discussion The study highlights the dual stressors of surgery and the pandemic, contributing to heightened preoperative anxiety. Findings indicate that significant anxiety levels were present, driven by fears related to surgery, anesthesia, and COVID-19. This aligns with other studies that report high preoperative anxiety levels exacerbated by the pandemic. The comprehensive assessment of anxiety factors underscores the need for tailored interventions to mitigate these anxieties. Conclusion The COVID-19 pandemic has significantly increased preoperative anxiety among surgical patients. Addressing both surgical and pandemic-related anxieties is crucial for improving patient outcomes. Healthcare providers should implement psychological support programs to alleviate these anxieties. Understanding the multifaceted nature of preoperative anxiety during the pandemic can enhance patient care.

5.
Indian J Crit Care Med ; 28(6): 561-568, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39130387

RESUMEN

Background: End-of-life care (EOLC) is a critical aspect of healthcare, yet accessing reliable information remains challenging, particularly in culturally diverse contexts like India. Objective: This study investigates the potential of artificial intelligence (AI) in addressing the informational gap by analyzing patient information leaflets (PILs) generated by AI chatbots on EOLC. Methodology: Using a comparative research design, PILs generated by ChatGPT and Google Gemini were evaluated for readability, sentiment, accuracy, completeness, and suitability. Readability was assessed using established metrics, sentiment analysis determined emotional tone, accuracy, and completeness were rated by subject experts, and suitability was evaluated using the Patient Education Materials Assessment Tool (PEMAT). Results: Google Gemini PILs exhibited superior readability and actionability compared to ChatGPT PILs. Both conveyed positive sentiments and high levels of accuracy and completeness, with Google Gemini PILs showing slightly lower accuracy scores. Conclusion: The findings highlight the promising role of AI in enhancing patient education in EOLC, with implications for improving care outcomes and promoting informed decision-making in diverse cultural settings. Ongoing refinement and innovation in AI-driven patient education strategies are needed to ensure compassionate and culturally sensitive EOLC. How to cite this article: Gondode PG, Khanna P, Sharma P, Duggal S, Garg N. End-of-life Care Patient Information Leaflets-A Comparative Evaluation of Artificial Intelligence-generated Content for Readability, Sentiment, Accuracy, Completeness, and Suitability: ChatGPT vs Google Gemini. Indian J Crit Care Med 2024;28(6):561-568.

6.
Plant Dis ; 2024 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-39148366

RESUMEN

Cenchrus americanus (L.) Morrone (Poaceae), is an important millet crop cultivated mainly in arid and semiarid regions and is a staple food grain for millions of people. During 2021 July surveys in the pearl millet fields in Mysore (12°30'55" N; 76°56'54" E), Karnataka, India, plants showed spathe blight and leaf spot disease with an overall incidence ranging from 5 - 8% in the 15 hectares surveyed. Infected leaves appeared brown, and lesions extended to the sheath. Some spathes were also found infected with similar symptoms. Diseased leaves and spathes were collected (n = 5 each) for pathogen identification. Samples were cut into small pieces (0.5 cm2), sterilized with sodium hypochlorite (2%, v/v), and blotted dried. The associated fungal pathogen was isolated on potato dextrose agar (PDA) medium amended with Streptomycin (40 mg/L) and incubated at 28 ºC for 1 week. Colonies were grey, fluffy, cottony with an irregular margin, undulate and dark brown in the back of the plate. Conidiophores were pale brown, erect, slightly curved, septate, unbranched, verruculose and measured 27.1 - 94 µm in length × 2.3 - 4.5 µm in width (n = 20). Conidiogenous cells were brown, subcylindrical, irregularly shaped, and conidia were straight, mainly elliptical, dark brown smooth, with two to three septa, with measurements of 11.1 - 26.4 µm by 5.7 - 14.3 µm (n = 50). Based on morphological characters, the pathogen was identified as Curvularia sp. Two representative isolates (UOMPM1 & UOMPM2) were molecularly identified. The total genomic DNA was extracted with a CTAB method, and ITS, GAPDH and tef-1α loci were amplified using primers ITS1/ITS4 (White et al., 1990), GPD1/GPD2 (Berbee et al., 1999) and EF1983F/EF-2218R (Schoch et al., 2009) respectively. ITS sequence had 100% similarity (706/706bp) with reference sequence C. spicifera (MH863648; HF934915 & HF934916); tef-1α sequence had 100% (933/933bp) identity with C. spicifera (KM062878, KJ939505), and the GAPDH sequence was 99.8% identical to that of Curvularia sp. (MG979055), and C. spicifera (MH809681). Combined dataset of concatenated sequence (ITS-GAPDH-tef-1α) was used in a phylogenetic analysis and revealed that the isolates were in a common clade with the isolate of Curvularia spicifera (CBS 274.52) thus, confirming the identity of the isolated pathogen as C. spicifera. The sequences obtained in the present study were deposited in the GenBank (ITS: OQ253406, OQ253407; LSU: OQ253429, OQ253430; GAPDH: OQ263372, OQ263373 & TEF: OQ263374, OQ263375). Pathogenicity test was carried out by inoculating (foliar /whole plant spray) 60 healthy pearl millet plants (45-days old), grown in field plot with spore suspension (105 conidia/ml). Control plants (n=20) were treated with sterile water. The experiments were conducted in triplicates and repeated twice. Development of disease symptoms was recorded on 41 plants, and all control plants remained healthy. The identity was confirmed after re-isolation as C. spicifera based on cultural and molecular sequence analysis. To our knowledge, this is the first report of C. spicifera causing a leaf spot and spathe blight disease of pearl millet in India. This disease seriously affects grain production, and effective disease management strategies need to be investigated.

7.
Pain Manag ; 14(5-6): 273-281, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38995181

RESUMEN

Aim: Diabetic peripheral neuropathy (DPN) induces chronic neuropathic pain in diabetic patients. Current treatments like pregabalin and duloxetine offer limited efficacy. This study evaluates combining pregabalin and duloxetine versus pregabalin alone for DPN pain relief, and explores gene modulation (PPARγ and Akt) to understand neuropathic pain's molecular basis.Materials & methods: Diabetic patients with DPN were randomized into groups receiving combination therapy or pregabalin alone for 4 weeks. Pain intensity, gene expression and quality of life were assessed.Results: Combination therapy significantly reduced pain, improved quality of life and upregulated PPARγ and Akt genes compared with monotherapy.Conclusion: Pregabalin and duloxetine combination therapy in DPN led to PPARγ mRNA upregulation and negative correlation of Akt gene expression with pain scores. This combination therapy effectively reduced pain and improved quality of life.Clinical Trial Registration: CTRI/2021/02/031068.


Combining medicines to reduce nerve pain in diabetic patientsWhat is this article about? People with diabetes often have nerve pain called diabetic peripheral neuropathy (DPN). Some medicines like pregabalin and duloxetine help, but are not enough. This study tested if using both medicines together works better than using just pregabalin. The study also looked at how these medicines affect certain genes.What were the results? Patients with DPN took either both medicines or just pregabalin for 4 weeks. The combined treatment reduced pain, improved life quality and affected certain genes.What do the results of the study mean? Using pregabalin and duloxetine together can reduce DPN pain more effectively. This offers hope for better treatment options.


Asunto(s)
Analgésicos , Neuropatías Diabéticas , Quimioterapia Combinada , Clorhidrato de Duloxetina , PPAR gamma , Pregabalina , Clorhidrato de Duloxetina/administración & dosificación , Humanos , Pregabalina/administración & dosificación , Pregabalina/farmacología , Neuropatías Diabéticas/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Femenino , Analgésicos/administración & dosificación , Analgésicos/farmacología , PPAR gamma/genética , Anciano , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Neuralgia/tratamiento farmacológico , Neuralgia/genética , Calidad de Vida , Adulto , Dimensión del Dolor
8.
J Fr Ophtalmol ; 47(7): 104242, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39013268

RESUMEN

In the last decade, artificial intelligence (AI) has significantly impacted ophthalmology, particularly in managing corneal diseases, a major reversible cause of blindness. This review explores AI's transformative role in the corneal subspecialty, which has adopted advanced technology for superior clinical judgment, early diagnosis, and personalized therapy. While AI's role in anterior segment diseases is less documented compared to glaucoma and retinal pathologies, this review highlights its integration into corneal diagnostics through imaging techniques like slit-lamp biomicroscopy, anterior segment optical coherence tomography (AS-OCT), and in vivo confocal biomicroscopy. AI has been pivotal in refining decision-making and prognosis for conditions such as keratoconus, infectious keratitis, and dystrophies. Multi-disease deep learning neural networks (MDDNs) have shown diagnostic ability in classifying corneal diseases using AS-OCT images, achieving notable metrics like an AUC of 0.910. AI's progress over two decades has significantly improved the accuracy of diagnosing conditions like keratoconus and microbial keratitis. For instance, AI has achieved a 90.7% accuracy rate in classifying bacterial and fungal keratitis and an AUC of 0.910 in differentiating various corneal diseases. Convolutional neural networks (CNNs) have enhanced the analysis of color-coded corneal maps, yielding up to 99.3% diagnostic accuracy for keratoconus. Deep learning algorithms have also shown robust performance in detecting fungal hyphae on in vivo confocal microscopy, with precise quantification of hyphal density. AI models combining tomography scans and visual acuity have demonstrated up to 97% accuracy in keratoconus staging according to the Amsler-Krumeich classification. However, the review acknowledges the limitations of current AI models, including their reliance on binary classification, which may not capture the complexity of real-world clinical presentations with multiple coexisting disorders. Challenges also include dependency on data quality, diverse imaging protocols, and integrating multimodal images for a generalized AI diagnosis. The need for interpretability in AI models is emphasized to foster trust and applicability in clinical settings. Looking ahead, AI has the potential to unravel the intricate mechanisms behind corneal pathologies, reduce healthcare's carbon footprint, and revolutionize diagnostic and management paradigms. Ethical and regulatory considerations will accompany AI's clinical adoption, marking an era where AI not only assists but augments ophthalmic care.

9.
Front Vet Sci ; 11: 1419573, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071790

RESUMEN

Aim/objectives: This study examines the in vitro impact of an ethanolic extract derived from Bryonia laciniosa seeds on the Gir bull (Bos indicus) spermatozoa. The objective is to thoroughly assess the effects of the seed extract on the physiological parameters of bull spermatozoa, followed by evaluating its effects on X and Y-bearing spermatozoa and its impact on gene expression through transcriptome profiling. Material method: For this study, one Gir bull was selected, and 12 ejaculates were collected at one-week time intervals. Sperm cells were isolated from each ejaculate and incubated with varying concentrations of the ethanolic extract. The physiological parameters of the spermatozoa were assessed using Computer Assisted Semen Analysis (CASA) and compared with control groups to evaluate the extract's effects on sperm quality and motility. Results and discussion: At a concentration of 18 mg/mL B. laciniosa extract, we noticed a statistically significant 16.4% increase in sperm motility (p = 0.0065). In order to understand the specific effect on X and Y-bearing spermatozoa, motile and non-motile sperm separated by glass wool column method and further evaluated for quantification of X and Y-bearing sperm in all samples by ddPCR. To understand the effect of B. laciniosa extract on spermatozoa at the molecular level, whole transcriptome profiling was carried out using Illumina MiSeq. Transcriptome profiling revealed 81 genes that were expressed differently between the group treated with the extract and the control group. The current investigation revealed an increase in the expression of TLX1, CRYGB, KLF13, and ZAR1 transcripts, which play a role in embryonic development. In addition, several genes have been identified that are involved in sperm motility, such GSK3B, LAPRS, MAPK1, CAMK2B, and AQP7. The findings exhibited the therapeutic effectiveness of B. laciniosa seeds in augmenting fertility through a synergistic blend of activities, including enhanced sperm motility and positive influence on embryogenesis.

10.
Org Lett ; 26(30): 6385-6389, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39023917

RESUMEN

A facile one-pot approach for the azidodifluoromethylation of aldehydes via in situ-generated azidodifluoromethenide (N3CF2-) utilizing commercially available TMSCF2Br and NaN3 is disclosed. The formed O-silyl ether products are obtained in yields of up to 91% in short reaction times at ambient temperature. Examples of both inter- and intramolecular [3 + 2] azide-alkyne cycloaddition reactions of the installed azidodifluoromethyl handles are also presented, demonstrating the prospective synthetic and biochemical functionality and utility.

11.
Eur J Pharmacol ; 978: 176796, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38945286

RESUMEN

The purpose of this study was to determine the receptor subtype and the underlying mechanisms involved in the relaxant effect to leptin in mid- and late-pregnant mouse uterus. We determined the relative mRNA expression of receptor subtypes, eNOS, and BKCa channel by quantitative PCR and also the overall receptor expression by immunohistochemistry. Isometric tension studies were conducted to evaluate the effects of leptin and to delineate its mechanisms. A selective siRNA for the ObRb receptor was used to determine the participation of the receptor subtype in biochemical and molecular effects of leptin. The relaxant response to leptin was greater in mid-pregnancy compared to late pregnancy and was mediated by the activation of BKCa channels by eNOS-derived nitric oxide in an ObRb receptor-dependent manner. In comparison to mid-pregnancy, expression of short forms (mainly ObRa receptor) of the receptor was significantly increased in late pregnancy, whereas ObRb receptor expression was similar in both phases. The results of the study suggest that ObRb receptor mediates leptin-induced increase in eNOS expression and NO synthesis. Leptin-induced eNOS expression and activation cause cGMP-independent stimulation of BKCa channels causing uterine relaxation. Increased short forms of the receptors and reduced BKCa channels exert a negative effect on uterine relaxation in late pregnancy. Leptin may have a physiological role in maintaining uterine quiescence in mid-pregnancy and its reduced relaxant response in late gestation may facilitate labor. Further, ObRb receptor agonists may be useful in the management of preterm labor.


Asunto(s)
Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio , Leptina , Óxido Nítrico Sintasa de Tipo III , Óxido Nítrico , Receptores de Leptina , Transducción de Señal , Útero , Animales , Femenino , Ratones , Embarazo , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/metabolismo , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/genética , Leptina/farmacología , Leptina/metabolismo , Relajación Muscular/efectos de los fármacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Receptores de Leptina/metabolismo , Receptores de Leptina/genética , Transducción de Señal/efectos de los fármacos , Útero/metabolismo , Útero/efectos de los fármacos
12.
Int J Biol Macromol ; 273(Pt 1): 132991, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38862048

RESUMEN

One of the main issues that customers worldwide have is food adulteration. In commercial packages, freshness cannot always be determined visually. Here, we propose sensitive films for use in food packaging that could alter colour to indicate a change in freshness. Hybrid, multifunctional, and eco-friendly films were prepared from polyvinyl alcohol/palmyra root sprout (PVA/PRS), fused with soy protein isolate carbon dot (CD), Boswellia serrata (BS), and Clitoriaternatea anthocyanin (CTE). The films showed pH sensitivity, antioxidant, and UV barrier properties. By creating hydrogen bonds between PRS and the other fillers, adding these substances makes PVA less crystallized. These interactions were verified by infrared Fourier-transform analysis. When compared to PVA, PRS films had significantly lower moisture content and swelling ratios. The UV-blocking capabilities of the films were greatly improved by the addition of CD, BS, and CTE without compromising their mechanical, thermal, or water vapor barrier properties. The composite film PVA/PRS/CD/BS/CTE exhibited a maximum tensile strength value of 69.47 ± 1.49 MPa. The CT extract provides the film with superior antioxidant properties. The colorimetric films PVA/PRS/CTE and PVA/PRS/CD/BS/CTE showed distinct pH-responsive colour-change properties as well as good colour stability. The colorimetric films were used to test the freshness of sardine fish, and they revealed unique colour changes that indicated whether the fish sample was spoiled or not.


Asunto(s)
Antocianinas , Antioxidantes , Boswellia , Carbono , Raíces de Plantas , Alcohol Polivinílico , Alcohol Polivinílico/química , Antocianinas/química , Antocianinas/análisis , Animales , Raíces de Plantas/química , Antioxidantes/química , Antioxidantes/análisis , Carbono/química , Boswellia/química , Biopelículas , Embalaje de Alimentos/métodos , Peces , Concentración de Iones de Hidrógeno , Puntos Cuánticos/química
13.
Phys Chem Chem Phys ; 26(21): 15125-15129, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38764422

RESUMEN

The strong two-photon induced nonlinear absorption and self-focusing type positive nonlinear refraction are pronounced by the structural engineering in ß-functionalized cobalt corroles.

14.
Opt Lett ; 49(7): 1721-1724, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560846

RESUMEN

The intricate spectrally resolved optical nonlinearities resulting from a spectrally broad femtosecond Gaussian laser pulse have been unraveled using a single-scan and spectrometer-based nonlinear optical probing technique. The interaction of the broad femtosecond laser pulse with a strongly absorbing organic dye has unveiled a remarkably distinct nonlinear absorption behavior across the broad spectral window. The nonlinear absorption behavior unveils an unusual transition from the reverse saturation absorption (RSA) to the saturation absorption (SA) as we sweep the wavelength on both sides of the central wavelength of the excitation laser pulse. A competition between the band-filling and excited-state absorption results in such a dramatic switch-over from the RSA to the SA due to the variation of the intensity distribution across the Gaussian pulse spectrum. On the other hand, the nonlinear refraction studies dictate more over the constant Kerr-type positive nonlinear refractive indices across the entire laser pulse, with a pronounced contribution from the nonlinear absorption phase dominating at the center of the pulse. The presented technique establishes a robust and simple spectrometer-based technique that offers new, to the best of our knowledge, avenues for estimating optical nonlinearities for rapid nonlinear optical measurements.

15.
RSC Adv ; 14(19): 13291-13305, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38655486

RESUMEN

Cycloplatination of symmetrical N,N',N''-triarylguanidines, (ArNH)2C[double bond, length as m-dash]NAr with cis-[Pt(TFA)2(S(O)Me2)2] in toluene afforded cis-[Pt(TAG)(TFA)(S(O)Me2)] (TAG = triarylguanidinate(1-)-κC,κN; TFA = OC(O)CF3; 6-9) in 75-82% yields. The reactions of 6-9 and the previously known cis-[Pt(TAG)X(S(O)Me2)] (X = Cl (1) and TFA (2-5)) with acetylacetone (acacH) or 2-picolinic acid (picH) in the presence of a base afforded [Pt(TAG)(acac)] (acac = acetylacetonate-κ2O,O'; 10-18) and [Pt(TAG)(pic)] (pic = 2-picolinate-κN,κO; 19) in high yields. The new complexes were characterised by analytical, IR and multinuclear NMR spectroscopies. Further, molecular structures of 11, 12, 13·0.5 toluene and 14-19 were determined by single crystal X-ray diffraction. Absorption spectra of 10-19 in solution and their emission spectra in crystalline form were measured. Platinacycles 10-19 are bluish green light emitter in the crystalline form, and emit in the λPL = 488-529 nm range (11 and 13-19) while 12 emits at λPL = 570 nm. Unlike other platinacycles, the emission band of 12 is broad, red shifted, and this pattern is ascribed to the presence of an intermolecular N-H⋯Pt interaction involving the endocyclic amino unit of the six-membered [Pt(TAG)] ring and the Pt(ii) atom in the adjacent molecule in an asymmetric unit of the crystal lattice. Lifetime measurements were carried out for all platinacycles in crystalline form, which revealed lifetime in the order of nanoseconds. The origin of absorption and emission properties of 11, 15, 18 and 19 were studied by TD-DFT calculations.

16.
ChemSusChem ; : e202301789, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594207

RESUMEN

Ionic liquids have been studied as CO2 capture agents. However, they are rarely used in combined CO2 capture and conversion processes. Utilizing imidazolium-based ionic liquids, the conversion of CO2 to methanol was greatly improved in polyamine assisted systems catalyzed by homogeneous pincer catalysts with Ru and Mn metal centers. Among the ionic liquids tested, [BMIM]OAc was found to perform the best under the given reaction conditions. Among the polyamine tested, pentaethylenehexamine (PEHA) led to the highest conversion rates. Ru-Macho and Ru-Macho-BH were the most active catalysts. Direct air capture utilizing PEHA as the capture material was also demonstrated and produced an 86 % conversion of the captured CO2 to methanol in the presence of [BMIM]OAc.

17.
ACS Appl Mater Interfaces ; 16(13): 16996-17006, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38514247

RESUMEN

The present work demonstrates the ultrafast carrier dynamics and third-order nonlinear optical properties of electrochemically fabricated free-standing porous silicon (FS-PSi)-based optical microcavities via femtosecond transient absorption spectroscopy (TAS) and single-beam Z-scan techniques, respectively. The TAS (pump: 400 nm, probe: 430-780 nm, ∼70 fs, 1 kHz) decay dynamics are dominated by the photoinduced absorption (PIA, lifetime range: 4.7-156 ps) as well as photoinduced bleaching (PIB, 4.3-324 ps) for the cavity mode (λc) and the band edges. A fascinating switching behavior from the PIB (-ve) to the PIA (+ve) has been observed in the cavity mode, which shows the potential in ultrafast switching applications. The third-order optical nonlinearities revealed an enhanced two-photon absorption coefficient (ß) in the order of 10-10 mW-1 along with the nonlinear refractive index (n2) in the range of 10-17 m2 W-1. Furthermore, a real-time sensing application of such FS-PSi microcavities has been demonstrated for detecting organic solvents by simultaneously monitoring the kinetics in reflection and transmission mode.

18.
Mitochondrion ; 76: 101874, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38514017

RESUMEN

Since the discovery of membrane contact sites between ER and mitochondria called mitochondria-associated membranes (MAMs), several pieces of evidence identified their role in the regulation of different cellular processes such as Ca2+ signalling, mitochondrial transport, and dynamics, ER stress, inflammation, glucose homeostasis, and autophagy. The integrity of these membranes was found to be essential for the maintenance of these cellular functions. Accumulating pieces of evidence suggest that MAMs serve as a platform for autophagosome formation. However, the alteration within MAMs structure is associated with the progression of neurodegenerative diseases. Dysregulated autophagy is a hallmark of neurodegeneration. Here, in this review, we highlight the present knowledge on MAMs, their structural composition, and their roles in different cellular functions. We also discuss the association of MAMs proteins with impaired autophagy and their involvement in the progression of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease.


Asunto(s)
Autofagia , Membranas Asociadas a Mitocondrias , Enfermedades Neurodegenerativas , Animales , Humanos , Autofagia/fisiología , Proteínas de la Membrana/metabolismo , Mitocondrias/metabolismo , Membranas Asociadas a Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología
19.
Langmuir ; 40(10): 5401-5408, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38426862

RESUMEN

Increasing carbon dioxide emissions has sparked a growing interest in capturing these emissions at the source of their release. For such processes, amines can be used as carbon dioxide capture agents. Herein, CO2 was captured under ambient conditions using solutions of amines and polyamines in ethylene glycol. The captured solutions were then successfully hydrogenated to methanol under hydrogen pressure with a heterogeneous Cu/ZnO/Al2O3 industrial catalyst. An extensive amine scope found that tetramethyl-1,6-hexanediamine, with two tertiary amine sites, provided the highest methanol productivity. This reaction was then optimized to achieve up to 89% methanol yield under relatively mild conditions of 250 °C and 80 bar H2 pressure. The catalyst was shown to be recyclable over five reaction cycles.

20.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38117199

RESUMEN

The effect of pulse-modulated sub-RF range (100 kHz-1 MHz) excitation on atmospheric pressure argon plasma jet characteristics is studied. For this, a suitable power supply is developed, offering a sub-µs rise time with control of different parameters, such as voltage amplitude, pulse modulation frequency in the range of 1-30 kHz, and an oscillation frequency of ∼520 kHz, which can affect the plasma behavior. Plasma characteristics, such as reactive species generation, ionic composition, plasma plume length, and gas temperature, are evaluated qualitatively and quantitatively by employing diagnostics such as optical emission spectroscopy, molecular beam mass spectrometry, and optical imaging. Experimental observations indicate that the gas temperature of the plasma jet and plume length increase with the applied voltage for all pulse modulation frequencies, with a maximum value of ∼(325 ± 2 K) and a maximum length of ∼(23 ± 3 mm), respectively, at 30 kHz and 9 kVpp. The emission intensities of OH• and O• lines show an incremental behavior with the applied voltage across all pulse modulation frequencies. The relative yield of different positive (OH+, O+, etc.) and negative (OH-, O-, etc.) ions also increases with the applied voltage for all pulse modulation frequencies with maximum values of ∼(7.6%, 9.9%) and (3.9%, 9.4%), respectively; these are relatively close to RF excited ionic concentrations reported previously. Attaining a high plasma length and species yield signify the features of both kHz and RF atmospheric plasmas. This study offers significant insights and flexibility into exploring the impact of different RF frequency regimes on plasma characteristics.

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