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BACKGROUND: Migraine is a disabling primary headache disorder characterized by recurrent episodes of headache. Migraine not only imposes a burden on the sufferer but also imposes a burden on their family members too. A holistic approach is more essential in the management of migraine and family members should also be included in the management of migraine. There are no published studies done in India so far to look for the impact of migraine on partners and adolescent children (IMPAC). This pilot study was done to assess the IMPAC. OBJECTIVE: The objective of the study was to study the IMPAC. MATERIALS AND METHODS: In this descriptive study, 130 chronic migraine patients were observed in a row during 9 months. The impact of migraine on family members as well as migraine disability and Migraine-specific Quality of Life (MSQoL) was evaluated using validated questionnaires. RESULTS: One hundred and thirty chronic migraine patients were studied as part of this study. The mean age of the study population was 34.43 ± 9.002 years, and two-third of the participants were female. The majority of the participants had a moderate-to-severe disability due to migraine and had negatively impacted their MSQoL. The impact of migraine on family members was moderate-to-severe grade in most of the participants and affected their family life negatively both with children and spouses. The males were more significantly affected than females in terms of MSQoL, anxiety, depression, and also on migraine's impact on family members. CONCLUSION: Migraine not only affects the sufferers, it also significantly affects their family members.
Résumé Contexte:La migraine est une céphalée primaire invalidante caractérisée par des épisodes récurrents de céphalées. La migraine n'impose pas seulementun fardeau pour la victime, mais impose également un fardeau aux membres de sa famille. Une approche holistique est plus essentielle dans la gestion des la migraine et les membres de la famille doivent également être impliqués dans la prise en charge de la migraine. Il n'existe jusqu'à présent aucune étude publiée en Inde pour rechercher l'impact de la migraine sur les partenaires et les adolescents (IMPAC). Cette étude pilote a été réalisée pour évaluer l'IMPAC.Objectif:L'objectif de l'étude était d'étudier l'IMPAC.Matériels et méthodes:Dans cette étude descriptive, 130 patients migraineux chroniques ont été observés d'affilée pendant 9 mois. L'impact de la migraine sur les membres de la famille ainsi que l'incapacité migraineuse et la qualité de vie spécifique à la migraine (MSQoL) ont été évalués à l'aide de questionnaires validés.Résultats:Cent trente patients migraineux chroniques ont été étudiés dans le cadre de cette étude. L'âge moyen de la population étudiée était de 34,43 ± 9,002 ans et les deux tiers des participants étaient des femmes. La majorité des participants souffraient d'un handicap modéré à sévère dû à une migraine et avaient eu un impact négatif sur leur MSQoL. L'impact de la migraine Les effets sur les membres de la famille étaient modérés à sévères chez la plupart des participants et affectaient négativement leur vie familiale, tant avec les enfants que avec les conjoints. Les hommes ont été plus significativement touchés que les femmes en termes de MSQoL, d'anxiété, de dépression, ainsi que d'impact de la migraine sur les membres de la famille.Conclusion:La migraine n'affecte pas seulement les personnes qui en souffrent, elle affecte également de manière significative les membres de leur famille.
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Família , Transtornos de Enxaqueca , Qualidade de Vida , Humanos , Transtornos de Enxaqueca/psicologia , Transtornos de Enxaqueca/epidemiologia , Masculino , Feminino , Estudos Transversais , Índia/epidemiologia , Adulto , Família/psicologia , Inquéritos e Questionários , Pessoa de Meia-Idade , Adolescente , Projetos Piloto , Ansiedade/epidemiologia , Ansiedade/psicologia , Adulto Jovem , Efeitos Psicossociais da Doença , Criança , Depressão/epidemiologia , Depressão/psicologiaRESUMO
This study reveals a new non-covalent interaction called a π-hole halogen bond, which is directional and potentially non-linear compared to its sister analog (σ-hole halogen bond). A π-hole is shown here to be observed on the surface of halogen in halogenated molecules, which can be tempered to display the aptness to form a π-hole halogen bond with a series of electron density-rich sites (Lewis bases) hosted individually by 32 other partner molecules. The [MP2/aug-cc-pVTZ] level characteristics of the π-hole halogen bonds in 33 binary complexes obtained from the charge density approaches (quantum theory of intramolecular atoms, molecular electrostatic surface potential, independent gradient model (IGM-δginter)), intermolecular geometries and energies, and second-order hyperconjugative charge transfer analyses are discussed, which are similar to other non-covalent interactions. That a π-hole can be observed on halogen in halogenated molecules is substantiated by experimentally reported crystals documented in the Cambridge Crystal Structure Database. The importance of the π-hole halogen bond in the design and growth of chemical systems in synthetic chemistry, crystallography, and crystal engineering is yet to be fully explicated.
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Halogênios , Eletricidade Estática , Halogênios/química , Modelos Moleculares , Teoria Quântica , Elétrons , Termodinâmica , Bases de Lewis/química , HalogenaçãoRESUMO
Background: Type 2 Diabetes (T2D) is a global challenge with rising prevalence, inadequate compliance, and poor outcomes. Aims: Assess the effect of a 2-only-daily-meals with exercise lifestyle (2-OMEX) on (a) HbA1c, (b) anti-diabetic medication count (ADMC), (c) Kcal intakes, body weight, fasting insulin, and subjective well-being. Materials and Methods: This is a single-arm follow-up study conducted in a free 2-OMEX clinic in 2019-2020. Information for two meals and exercise compliance was obtained during the clinic visit. HbA1c was tested by HPLC and fasting insulin by the CLIA/CMIA method in private laboratories. Results: Eligible subjects (f = 49, m = 116) completing two or more visits and 60 days of follow-up had a mean age of 55.92 (10.43) years, a T2D duration of 8.20 (6.28) years, and a median observation period of 140 days. Statistically significant changes included HbA1c decline from 7.69 (1.70) to 7.00 (1.20) gm% (equivalent by the LogNormal method to 1.088 gm%), average weight loss at 5%(m), and 2%(f). ADMC declined from 2.32 to 2.14, the difference being significant with the WSR test (z = 2.0087, P = 0.0223). Subjects attaining anti-diabetic medication-free and normoglycemic status (HbA1c < 6.5 gm%) were 20 (12%). The number attaining HbA1c ≤ 7 gm%) significantly rose from 73 (44%) to 101 (61%) with an ADMC of 1.9 (chi-square = 9.531, df1, P = 0.0020203). Participants reported 'feeling energetic' (79%), feeling lighter (50%), and better sleep (35%). Average energy intakes dropped by 120 Kcal to 1580/day. Fasting insulin remained unchanged, from 12.61 (11.06) to 12.34 (11.78) mlU/L. The dropout rate was 35%. Conclusions: The 2-OMEX lifestyle showed a sizeable, favorable, and significant change in HbA1c, body weight, ADMC use in five months, and subjective benefits. Studies are necessary for remission impact and pathways.
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Diospyros peregrina is a dioecious plant which is native to India. It belongs to the family of Ebenaceae and is extensively used to treat various ailments, such as leucorrhoea and other uterine-related problems. Though few studies have been on D. peregrina for their anti-tumour response, little is known. Therefore, this intrigued us to understand its immunomodulator capabilities on various types of cancer extensively. Our primary focus is on NSCLC (Non-Small Cell Lung Cancer), which is ranked as the second largest form of cancer in the world, and the treatments demand non-invasive agents to target NSCLC effectively. In an objective to generate an efficient Lung Cancer Associated Antigen (LCA) specific anti-tumour immune response, LCA was presented using dendritic cells (DCs) in the presence of D. peregrina fruit preparation (DFP). Moreover, we also investigated DFP's role in the differentiation of T-helper (TH) cells. Therefore, this study aimed at better LCA presentation mediated by DFP by activating the LCA pulsed DCs and T helper cell differentiation for better immune response. DCs were pulsed with LCA for tumour antigen presentation in vitro, with and without DFP. Differentially pulsed DCs were irradiated to co-culture with autologous and allogeneic lymphocytes. Extracellular supernatants were collected for the estimation of cytokine levels by ELISA. LDH release assay was performed to test Cytotoxic T lymphocytes (CTLs) mediated lung tumour cell cytotoxicity. Thus, DFP may be a potential vaccine to generate anti-LCA immune responses to restrict NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Diospyros , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Apresentação de Antígeno , Frutas , Células Dendríticas , Linfócitos T Citotóxicos , Diferenciação CelularRESUMO
Bacopa monnieri (L) Wettst, commonly known as Brahmi, stands as a medicinal plant integral to India's traditional medical system, Ayurveda, where it is recognized as a "medhya rasayana"-a botanical entity believed to enhance intellect and mental clarity. Its significant role in numerous Ayurvedic formulations designed to address conditions such as anxiety, memory loss, impaired cognition, and diminished concentration underscores its prominence. Beyond its application in cognitive health, Brahmi has historically been employed in Ayurvedic practices for the treatment of inflammatory diseases, including arthritis. In contemporary biomedical research, Bacopa monnieri can attenuate the release of pro-inflammatory cytokines TNF-α and IL-6 in animal models. However, there remains a paucity of information regarding Bacopa's potential as an anticancer agent, warranting further investigation in this domain. Based on previous findings with Brahmi (Bacopa monnieri), the current study aims to find out the role of Brahmi plant preparation (BPP) in immunomodulatory actions on IDC. Employing a specific BPP concentration, we conducted a comprehensive study using MTT assay, ELISA, DNA methylation analysis, Western blotting, ChIP, and mRNA profiling to assess BPP's immunomodulatory properties. Our research finding showed the role of BPP in augmenting the action of T helper 1 (TH1) cells which secreted interferon-γ (IFN-γ) which in turn activated cytotoxic T-lymphocytes (CTL) to kill the cells of IDC (*p < 0.05). Moreover, we found out that treatment with BPP not only increased the activities of tumor-suppressor genes (p53 and BRCA1) but also decreased the activities of oncogenes (Notch1 and DNAPKcs) in IDC (*p < 0.05). BPP had an immense significance in controlling the epigenetic dysregulation in IDC through the downregulation of Histone demethylation & Histone deacetylation and upregulation of Histone methylation and Histone acetylation (*p < 0.05). Our Chromatin immunoprecipitation (ChIP)-qPCR data showed BPP treatment increased percentage enrichment of STAT1 & BRCA1 (*p < 0.05) and decreased percentage enrichment of STAT3, STAT5 & NF ΚB (*p < 0.05) on both TBX21 and BRCA1 gene loci in IDC. In addition, BPP treatment reduced the hypermethylation of the BRCA1-associated-DNA, which is believed to be a major factor in IDC (*p < 0.05). BPP not only escalates the secretion of type 1 specific cytokines but also escalates tumor suppression and harmonizes various epigenetic regulators and transcription factors associated with Signal Transducer and Activator of Transcription (STAT) to evoke tumor protective immunity in IDC.
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Bacopa , Carcinoma Ductal , Neoplasias , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Histonas , CitocinasRESUMO
Precise control over polymer microstructure can enable the molecular tunability of material properties and represents a significant challenge in polymer chemistry. Stereoblock copolymers are some of the simplest stereosequenced polymers, yet the synthesis of stereoblock polyesters from prochiral or racemic monomers outside of "simple" isotactic stereoblocks remains limited. Herein, we report the development of irreversible chain-transfer ring-opening polymerization (ICT-ROP), which overcomes the fundamental limitations of single catalyst approaches by using transmetalation (e.g., alkoxide-chloride exchange) between two catalysts with distinct stereoselectivities as a means to embed temporally controlled multicatalysis in ROP. Our combined small-molecule model and catalytic polymerization studies lay out a clear molecular basis for ICT-ROP and are exploited to access the first examples of atactic-syndiotactic stereoblock (at-sb-st) polyesters, at-sb-st polyhydroxyalkanoates (PHAs). We achieve high levels of control over molecular weight, tacticity, monomer composition, and block structures in a temporally controlled manner and demonstrate that stereosequence control leads to polymer tensile properties that are independent of thermal properties.
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BACKGROUND: Alcohol dependence is a prevalent issue worldwide. The wives of persons with alcohol dependence (WPAD) often experience several psychological, physical, and social problems, and it is essential to identify their coping strategies. This study aims to explore the coping strategies employed by WPAD by conducting a focus group discussion (FGD). MATERIALS AND METHODS: This study was conducted among wives of persons with alcohol dependence during their husband's admission in the departments of Psychiatry and gastroenterology of St. John's Medical College Hospital, Bangalore, India, using qualitative research with phenomenological design. The inclusion criteria were being married and living with a person with alcohol dependence for more than three years and free from major psychiatric disorders and recruited through purposive sampling for six FGDs, which were conducted using a FGD guide and lasted approximately 60 to 90 minutes. The discussions were audio-recorded and transcribed verbatim. Thematic analysis was used to analyze the data. RESULTS: The study revealed that the WPAD adhered to various coping strategies to face the challenges of living with their husbands with alcohol dependence. It is observed that WPAD used emotion-focused coping, problem-focused coping and avoidance coping. CONCLUSIONS: This study highlighted the effective coping strategies adapted by WPAD to tackle the hardships related to their husband's alcoholic behavior and most of the WPAD used emotion-focused coping. This study provided valuable insights into the coping strategies used by wives of alcoholics and the challenges they faced in managing their spouse's addiction.
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Background: Psychological morbidities are one of the emerging global health problems. It affects a considerable number of ante-natal women leading to consequences during the postnatal period as well. We conducted this research to study the magnitude and determinants of psychological morbidities during pregnancy. Methods: In this study, we included 650 pregnant women from an established cohort of 2500 pregnant women and assessed the psychological morbidities among them using the GMHAT/PC tool. Results: The overall prevalence of psychological morbidities during pregnancy was 14.6%, with anxiety and depression being the leading ones. Low education levels, lower socio-economic status, unintended pregnancy, complicated previous pregnancy, lack of family and social support, and domestic violence increased the odds of psychological morbidity. On Multivariate logistic regression, Low education levels increased the odds to more than twice [illiterate/primary schooling OR: 4.00, p = 0.026; secondary schooling OR: 2.64, p = 0.034; high school OR: 2.60, p = 0.033] unintended pregnancy [OR: 1.91, p = 0.043] and lack of family support [OR: 7.19, p < 0.001] increased the odds of psychological morbidity among pregnant women. Conclusion: Bringing these issues to the mainstream and addressing them by developing interventions to address them during the lifecycle of a female will help to prevent episodes of psychological stress and morbidity among pregnant females.
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Orthotospoviruses, a genera of negative-sense ssRNA viruses transmitted by thrips, have gained significant attention in recent years due to their detrimental impact on diverse crops, causing substantial economic losses and posing threats to food security. Orthotospoviruses are characterised by a wide range of symptoms in plants, including chlorotic/necrotic spots, vein banding, and fruit deformation. Seven species, including four definite and three tentative species in the genus Orthotospovirus, have so far been documented on the crops of the Indian subcontinent. Management of Orthotospoviruses under field conditions is challenging since they have a wide host range, adaptation to versatile environmental conditions, a lack of promising resistance sources, and the ubiquitous nature of thrips and their transmission through a propagative manner. Our present review elucidates the significance, molecular biology and evolutionary relationship of Orthotospoviruses; vector population; and possible management strategies for Orthotospoviruses and their vectors in the scenario of the Indian subcontinent.
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Tisanópteros , Tospovirus , Animais , Doenças das Plantas , Tospovirus/genética , Tisanópteros/genética , Produtos Agrícolas , AgriculturaRESUMO
The research article investigates the effect of incorporating the guanidinium carbonate (GuC) salt into the poly vinylpyrrolidone (PVP) and polyethylene oxide (PEO) polymer matrix. Various weight percentages of GuC enriched PVP/PEO solid polymer electrolytes (SPEs) have been prepared by the simplest solution casting process. XRD analysis revealed that the incorporation of the GuC salt led to changes in the crystalline structure of the PVP/PEO. FTIR analysis confirms the presence of guanidinium carbonate in the blended polymeric system. FESEM imaging showed the uniform and smooth surface view of the electrolytes. DSC analysis suggests that the addition of the GuC led to a decrease in the melting temperature and an increase in the crystallisation temperature. The temperature-dependent dielectric analysis showed that the presence of the organic salt led to an increase in the dielectric constant of the polymer blend. Among all the prepared electrolytes, 25 wt.% GuC added polymer electrolyte achieved a higher conductivity of 3.00764 × 10-7 S/cm. Overall, the results of the study suggest that the incorporation of the GuC salt into the PVP/PEO can lead to significant changes in the structural, thermal, and dielectric properties of the blend. These findings have potential implications for the use of PVP/PEO blends in solid state battery applications.
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In this study, we present a robust approach that concurrently manages crystal growth and defect passivation within the perovskite layer through the introduction of a small molecule additiveâallantoin. The precise regulation of crystal growth in the presence of allantoin yields perovskite films characterized by enhanced morphology, larger grain size, and improved grain orientation. Notably, the carbonyl and amino groups present in allantoin passivate under-coordinated Pb2+ and I- defects, respectively, through molecular interactions. Trap density in the perovskite layer is measured, and it is 0.39 × 1016 cm-3 for the allantoin-incorporated device and 0.83 × 1016 cm-3 for the pristine device. This reduction in defects leads to reduced trap-assisted nonradiative recombination, as confirmed by the photoluminescence, transient photo voltage, and impedance measurements. As a result, when these allantoin-incorporated perovskite films are implemented as the active layer in solar cells, a noteworthy efficiency enhancement to 20.63% is attained, surpassing the 18.04% of their pristine counterparts. Furthermore, devices with allantoin exhibit remarkable operational stability, maintaining 80% of their efficiency even after 500 h of continuous illumination, whereas the pristine device degraded to 65% of its initial efficiency in 400 h. Also, allantoin-incorporated devices exhibited exceptional stability against high humidity and elevated temperatures.
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With advancement of hybrid and endovascular techniques, there are very few indications for open arch replacement. Major advancements in open arch replacement include antegrade perfusion-based cerebral protection, and an endovascular compliant arch replacement. In the present article, we demonstrate and describe our technique of Bentall's procedure and endovascular compliant arch replacement in a young Marfan's patient with chronic type A dissection and root aneurysm. Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-023-01560-1.
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BACKGROUND AND OBJECTIVE: Dental panoramic radiographs are utilized in computer-aided image analysis, which detects abnormal tissue masses by analyzing the produced image capacity to recognize patterns of intensity fluctuations. This is done to reduce the need for invasive biopsies for arriving to a diagnosis. The aim of the current study was to examine and compare the accuracy of several texture analysis techniques, such as Grey Level Run Length Matrix (GLRLM), Grey Level Co-occurrence Matrix (GLCM), and wavelet analysis in recognizing dental cyst, tumor, and abscess lesions. MATERIALS & METHODS: The current retrospective study retrieved a total of 172 dental panoramic radiographs with lesion including dental cysts, tumors, or abscess. Radiographs that failed to meet technical criteria for diagnostic quality (such as significant overlap of teeth, a diffuse image, or distortion) were excluded from the sample. The methodology adopted in the study comprised of five stages. At first, the radiographs are improved, and the area of interest was segmented manually. A variety of feature extraction techniques, such GLCM, GLRLM, and the wavelet analysis were used to gather information from the area of interest. Later, the lesions were classified as a cyst, tumor, abscess, or using a support vector machine (SVM) classifier. Eventually, the data was transferred into a Microsoft Excel spreadsheet and statistical package for social sciences (SPSS) (version 21) was used to conduct the statistical analysis. Initially descriptive statistics were computed. For inferential analysis, statistical significance was determined by a p value < 0.05. The sensitivity, specificity, and accuracy were used to find the significant difference between assessed and actual diagnosis. RESULTS: The findings demonstrate that 98% accuracy was achieved using GLCM, 91% accuracy using Wavelet analysis & 95% accuracy using GLRLM in distinguishing between dental cyst, tumor, and abscess lesions. The area under curve (AUC) number indicates that GLCM achieves a high degree of accuracy. The results achieved excellent accuracy (98%) using GLCM. CONCLUSION: The GLCM features can be used for further research. After improving the performance and training, it can support routine histological diagnosis and can assist the clinicians in arriving at accurate and spontaneous treatment plans.
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Abscesso , Cistos , Humanos , Estudos Retrospectivos , Aprendizado de MáquinaRESUMO
Background: Rhino-orbital-cerebral mucormycosis (ROCM) is a life-threatening condition caused by a saprophytic fungus that predominately affecting immune-compromised patients. Early diagnosis of ROCM is of utmost importance to start the treatment as early as possible to prevent early and horrible complications of the disease. Materials and methods: This retrospective study evaluated the imaging findings of 21 patients with biopsy and KOH mount-based evidence of invasive ROCM. The imaging was obtained from a Siemens Magnetom Amira 1.5T system with a strength of 1.5T or more. The spectrum of findings was evaluated for the sites of involvement, signal intensity, contrast characteristics, necrotic component as well as orbital, infratemporal, and intracranial extensions, especially cavernous sinuses, Meckel's cave, and the brain parenchyma. Results: The mean age of the patients was 55.8±10.9 years and included 71% male. All the patients were positive for COVID-19 and the majority were diabetic. MRI showed predominant involvement of the maxillary sinus (17, 81%) and the ethmoidal sinus (15, 71.4%). The orbital extension was present in 18 cases (86%). T1-weighted imaging showed iso to low signal intensity in involved sinuses in the majority of the patients (9, 42.9%). Heterogeneously high signal intensity was observed in T2-weighted and short tau inversion recovery images in all the patients. Heterogenous contrast enhancement was present in 20 (95.2%) patients. Conclusion: The imaging spectrum of ROCM is variable. Multiplanar MRI with postcontrast images is a very useful complementary tool to the clinical evaluation to assess the extent of disease and its complications, which has a high mortality. Clinicians and radiologists should be aware of the imaging spectrums of ROCM.
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Aortic dissections are associated with significant mortality and morbidity, with rapid treatment paramount. They are caused by a tear in the intimal lining of the aorta that extends into the media of the wall. Blood flow through this tear leads to the formation of a false passage bordered by the inner and outer layers of the media. Their diagnosis is challenging, with most deaths caused by aortic dissection diagnosed at post-mortem. Aortic dissections are classified by location and chronicity, with management strategies depending on the nature of the dissection. The Stanford method splits aortic dissections into type A and B, with type A dissections involving the ascending aorta. De Bakey classifies dissections into I, II or III depending on their origin and involvement and degree of extension. The key to diagnosis is early suspicion, appropriate imaging and rapid initiation of treatment. Treatment focuses on initial resuscitation, transfer (if possible and required) to a suitable specialist centre, strict blood pressure and heart rate control and potentially surgical intervention depending on the type and complexity of the dissection. Effective post-operative care is extremely important, with awareness of potential post-operative complications and a multi-disciplinary rehabilitation approach required. In this review article we will discuss the aetiology and classifications of aortic dissection, their diagnosis and treatment principles relevant to critical care. Critical care clinicians play a key part in all these steps, from diagnosis through to post-operative care, and thus a thorough understanding is vital.
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Achieving synchronization in coupled non-identical chaotic systems has been a difficult endeavor, and improving the stability of synchronization in such systems poses additional challenges. This research work addresses these challenges by identifying stable synchronization in coupled non-identical chaotic systems and enhancing its stability. The study explores chaotic attractors that arise from various system parameters to provide generalized results. Furthermore, the impact of the transient uncoupling factor on improving synchronization stability in coupled non-identical counter-rotating chaotic oscillators is discussed. By investigating these aspects, the research aims to contribute to the understanding and advancement of synchronization in coupled non-identical chaotic systems.
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The structural stability of the extensively studied organic-inorganic hybrid methylammonium tetrel halide perovskite semiconductors, MATtX3 (MA = CH3NH3+; Tt = Ge, Sn, Pb; X = Cl, Br, I), arises as a result of non-covalent interactions between an organic cation (CH3NH3+) and an inorganic anion (TtX3-). However, the basic understanding of the underlying chemical bonding interactions in these systems that link the ionic moieties together in complex configurations is still limited. In this study, ion pair models constituting the organic and inorganic ions were regarded as the repeating units of periodic crystal systems and density functional theory simulations were performed to elucidate the nature of the non-covalent interactions between them. It is demonstrated that not only the charge-assisted N-H···X and C-H···X hydrogen bonds but also the C-N···X pnictogen bonds interact to stabilize the ion pairs and to define their geometries in the gas phase. Similar interactions are also responsible for the formation of crystalline MATtX3 in the low-temperature phase, some of which have been delineated in previous studies. In contrast, the Tt···X tetrel bonding interactions, which are hidden as coordinate bonds in the crystals, play a vital role in holding the inorganic anionic moieties (TtX3-) together. We have demonstrated that each Tt in each [CH3NH3+â¢TtX3-] ion pair has the capacity to donate three tetrel (σ-hole) bonds to the halides of three nearest neighbor TtX3- units, thus causing the emergence of an infinite array of 3D TtX64- octahedra in the crystalline phase. The TtX44- octahedra are corner-shared to form cage-like inorganic frameworks that host the organic cation, leading to the formation of functional tetrel halide perovskite materials that have outstanding optoelectronic properties in the solid state. We harnessed the results using the quantum theory of atoms in molecules, natural bond orbital, molecular electrostatic surface potential and independent gradient models to validate these conclusions.
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Hidrogênio , Óxidos , Modelos MolecularesRESUMO
Titanium dioxide (TiO2) is one of the important functional materials owing to its diverse applications in many fields of chemistry, physics, nanoscience, and technology. Hundreds of studies on its physicochemical properties, including its various phases, have been reported experimentally and theoretically, but the controversial nature of relative dielectric permittivity of TiO2 is yet to be understood. Toward this end, this study was undertaken to rationalize the effects of three commonly used projector augmented wave (PAW) potentials on the lattice geometries, phonon vibrations, and dielectric constants of rutile (R-)TiO2 and four of its other phases (anatase, brookite, pyrite, and fluorite). Density functional theory calculations within the PBE and PBEsol levels, as well as their reinforced versions PBE+U and PBEsol+U (U = 3.0 eV), were performed. It was found that PBEsol in combination with the standard PAW potential centered on Ti is adequate to reproduce the experimental lattice parameters, optical phonon modes, and the ionic and electronic contributions of the relative dielectric permittivity of R-TiO2 and four other phases. The origin of failure of the two soft potentials, namely, Ti_pv and Ti_sv, in predicting the correct nature of low-frequency optical phonon modes and ion-clamped dielectric constant of R-TiO2 is discussed. It is shown that the hybrid functionals (HSEsol and HSE06) slightly improve the accuracy of the above characteristics at the cost of a significant increase in computation time. Finally, we have highlighted the influence of external hydrostatic pressure on the R-TiO2 lattice, leading to the manifestation of ferroelectric modes that play a role in the determination of large and strongly pressure-dependent dielectric constant.
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Obstructed hemivagina and ipsilateral renal agenesis (OHVIRA) syndrome also known as the Herlyn-Werner-Wunderlich Syndrome is a rare embryological disorder associated with Mullerian and mesonephric duct abnormality. Case presentation: The cases presented describe the imaging (ultrasound and MRI) findings of four young females who presented with dysmenorrhea and urinary complaints. All of them had solitary kidneys with a didelphic uterus and unilateral hematometrocolpos. A proximally blind-ending ureter with distal ectopic insertion, transverse vaginal septum, and left-sided endometrioma was seen. Clinical discussion: OHVIRA syndrome is associated with duplicated uterovaginal structure with OHVIRA. Ultrasound is the first line of investigation; however, MRI better delineates the anatomy and assists in preoperative planning. Conclusion: This report highlights that earlier clinical suspicion and imaging diagnosis of OHVIRA is crucial to prevent adverse outcomes and treating complications.