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1.
Dalton Trans ; 53(27): 11563-11577, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38921544

RESUMEN

An in situ hydrolysis of the P-Cl bonds of the carbophosphazene [{NC(NMe2)}2{NPCl2}] (LPCl2) in the presence of hydrated lanthanide(III) nitrates in a dichloromethane and methanol (2 : 1) solvent mixture afforded a series of novel 1D coordination polymers: [{Ln(LHPO2)3(NO3)2(CH3OH)(H2O)} (Cl)]n {where Ln(III) = Gd (1), Tb (2), Dy (3), or Er (4) and LHPO2 is the hydrolyzed carbophosphazene (LPCl2) ligand}. X-ray crystallographic analysis revealed that complexes 1-4 are isostructural and crystallized in the monoclinic crystal system having P21/c space group. The coordination polymers are formed because of the involvement of the geminal P(O)(OH) moieties of the carbophosphazene ligand. Each lanthanide(III) ion is 9-coordinate (9O) in a distorted muffin geometry. Magnetic measurements revealed that both DyIII and ErIII analogues exhibit field-induced single-molecule magnet (SMM) behavior at 0.8 kOe and 2.2 k Oe, respectively. At such dc fields, the dynamic magnetic susceptibility displays complex behavior with a triple magnetic relaxation contribution for 3, while two contributions were identified for 4. The observed static and dynamic magnetic behavior for complexes 1-4 were further rationalized with the aid of BS-DFT and CASSCF/SO-RASSI/SINGLE_ANISO calculations.

2.
Cureus ; 16(4): e59057, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38803756

RESUMEN

BRASH syndrome is a syndrome that comprises bradycardia, renal failure, atrioventricular nodal block, shock, and hyperkalemia. This syndrome is usually associated with a junctional rhythm. Early recognition of this clinical entity is crucial for appropriate management. In this case report, we describe a 70-year-old female who presented with BRASH syndrome-induced atrial fibrillation with a slow ventricular response.

3.
Cureus ; 16(2): e53789, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38465084

RESUMEN

Myocardial perfusion imaging (MPI) is fundamental to comparing coronary vessel perfusion levels and guides in identifying ischemic areas. However, false negatives, such as balanced ischemia, are important considerations in interpreting these results. In this case report, we describe a 77-year-old female who presented with cardiac chest pain with normal laboratory results, electrocardiogram, and imaging. However, given her history and risk factors, left heart catheterization was performed, which showed triple vessel coronary artery disease.

4.
ACS Appl Mater Interfaces ; 16(6): 8158-8168, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38301155

RESUMEN

Layered semiconductors of the V-VI group have attracted considerable attention in optoelectronic applications owing to their atomically thin structures. They offer thickness-dependent optical and electronic properties, promising ultrafast response time, and high sensitivity. Compared to the bulk, 2D bismuth selenide (Bi2Se3) is recently considered a highly promising material. In this study, 2D nanosheets are synthesized by prolonged sonication in two different solvents, such as N-methyl-2-pyrrolidone (NMP) and chitosan-acetic acid solution (CS-HAc), using the liquid-phase exfoliation (LPE) method. X-ray diffraction confirms the amorphous nature of exfoliated 2D nanosheets with maximum peak intensity at the same position (015) crystal plane as that obtained in its bulk counterpart. SEM confirms the thin 2D nanosheet-like morphology. Successful exfoliation of Bi2Se3 nanosheets up to five layers is achieved using CS-HAc solvent. The as-synthesized 2D nanosheets in different solvents are employed to fabricate the photodetector. At minimum selected power density, the photodetector fabricated using exfoliated ultrathin 2D nanosheets exhibits the highest range of responsivity, varying from 15 to 2.5 mA/W, and detectivity ranging from 2.83 × 109 to 6.37 × 107. Ultrathin 2D Bi2Se3 nanosheets have fast rise and fall times, ranging from 0.01 to 0.12 and 0.01 to 0.06 s, respectively, at different wavelengths. Ultrathin Bi2Se3 nanosheets have improved photodetection parameters as compared to multilayered nanosheets due to the high surface to volume ratio, reduced recombination and trapping of charge carrier, improved carrier confinement, and faster carrier transport due to the thin layer.

5.
PLoS One ; 19(2): e0297868, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38358991

RESUMEN

Entrepreneurial ventures are established in large numbers in China. The success rate of these entrepreneurial ventures is lower than that of new startups. Mismanagement and a lack of creative skills among entrepreneurs are cited as reasons for entrepreneurial failure in China. The current study investigates the impact of entrepreneurial networking and new venture intention on entrepreneurial success in China, with psychological capital and entrepreneurial optimism serving as moderators. 483 responses were collected from business students in China for data analysis. The findings of the study reveal that the impact of entrepreneurial networking and new venture intention on entrepreneurial success in China, with the moderating role of psychological capital and entrepreneurial optimism, is significant. The theoretical framework of this research has novelty as it introduces new moderating relationships of psychological capital and entrepreneurial optimism in the model of entrepreneurial success. Practically, this study has revealed that entrepreneurial success can be achieved with entrepreneurial networking, entrepreneurial optimism, psychological capital, and new venture intention. The directions of this research point out additional gaps in the literature that scholars should discuss in subsequent studies.


Asunto(s)
Comercio , Emprendimiento , Humanos , China , Análisis de Datos , Estudiantes
6.
Chem Asian J ; 19(1): e202300812, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-37961926

RESUMEN

Phosphonate and phosphate ligands have historically received less attention when compared to the widely prevalent carboxylate ligand system. Phosphonates possess multiple donating sites, often leading to the formation of larger aggregates with limited solubility. Conversely, the P-O bond within phosphates is highly susceptible to hydrolysis, resulting in the precipitation of insoluble compounds, particularly when interacting with lanthanide metal ions. However, over the past few decades, various synthetic approaches have emerged for the preparation and characterization of lanthanide complexes involving both phosphonate and phosphate ligands. Consequently, researchers have delved into exploring the magnetic properties of these complexes, such as their potential as single molecule magnets (SMMs) and their ability to exhibit a magnetocaloric effect (MCE). This review will encompass an examination of the crystal structures and magnetic characteristics of lanthanide complexes featuring phosphonate and phosphate ligands.

7.
Cureus ; 15(11): e48617, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38084179

RESUMEN

We present a case of a previously fit and well 28-year-old male who presented to the emergency department with respiratory distress and hypoxia four days after an alleged assault and blunt-force trauma to the chest wall. Initial clinical assessment and imaging suggested a likely diagnosis of delayed massive hemothorax associated with mediastinal shift. However, upon chest drain insertion, a large amount of pus was unexpectedly drained, leading to an immediate improvement in symptoms and restoration of mediastinal anatomy on repeat imaging. Our case illustrates that, although rare, empyemas can reach a significant volume before detection; they are capable of producing radiological and clinical intrathoracic tension configuration and can mimic hemothorax in the setting of trauma.

8.
Dalton Trans ; 52(41): 14807-14821, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37791680

RESUMEN

We report three CoII-based complexes with the general formula [CoII(L)(X)2] by changing the halide/pseudo-halide ions [X = NCSe (1SeCN); Cl (2Cl) and Br (3Br)]. The obtained τ5 and CShM values confirm a distorted square pyramidal geometry around the CoII ion in all these complexes. In these three complexes, the central CoII ion is situated above the basal plane of the square pyramidal geometry. The extent of distortion from the ideal SPY-5 geometry differs upon changing the coordinating halide/pseudo-halide ion in these complexes. This essentially results in the alteration of the anisotropic parameter D and hence impacts the magnetic properties in these complexes. This phenomenon has been corroborated with the aid of theoretical investigations. All these complexes display field-induced SIM behaviour with magnetic relaxation occurring through a combination of processes depending on the applied dc magnetic field values and dilution.

9.
Materials (Basel) ; 16(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687670

RESUMEN

Buildings use a significant percentage of the total energy consumed worldwide. Striving for energy conservation within buildings is of prime concern for researchers. Hence, scientists are aggressively exploring new energy storage and supply methods to reduce exorbitantly fluctuating energy demands and increase the share of renewable energy in building energy consumption. Solar systems that incorporate phase change materials (PCMs) for thermal storage have significant potential to serve in this context. These systems are not yet able to endure the significant energy demands, but they are being continually improved. The aim of this paper is to explore the existing solar PCM systems that are being studied or that are installed for use in indoor heating/cooling. As per the outcome of this systematic review, it has been observed that when coupled with solar thermal energy, the configuration of PCMs can either use passive or active techniques. Passive techniques are usually less efficient and more costly to implement in a building structure, resulting in active heat exchangers being widely implemented with better technical and economic results. At the same time, it has been observed that for most domestic buildings, organic PCMs with phase change temperatures of up to 42 °C and thermal conductivities of up to 0.56 W/m.K are most suitable for integration in solar thermal energy production. Hybrid systems are also commonly used for larger commercial buildings, in which the solar PCM system (SPCMS) provides a fraction of the total load. Additionally, the Stefan number is the most common technical parameter that is used to assess this performance, along with the effective thermal conductivity of the PCM after using enhancement techniques. The key economic indicator is annual savings per year, with most SPCMSs having a payback period of between 6 to 30 years. This review provides designers and researchers with key insights in terms of formulating a basis in the domain of coupling PCMs with solar thermal energy, especially within non-industrial buildings.

10.
Artículo en Inglés | MEDLINE | ID: mdl-37535282

RESUMEN

This study investigated the impact of efficiency, reliability, responsiveness, safety, and security on customer satisfaction with sustainable e-banking. The study used a quantitative methodology, with data collected from customers of commercial banks in South Punjab, Pakistan. A Likert scale questionnaire was used to collect cross-sectional data. A sample of 350 was analyzed using the Statistical Package for the Social Sciences (SPSS) for testing descriptive statistics, correlation analysis, and regression results. The study's results revealed that efficiency, reliability, responsiveness, safety, and security significantly impacted customer satisfaction with e-banking services. Efficiency and reliability were the most crucial factors influencing customer satisfaction, followed by safety, security, and responsiveness. The research findings have important implications for commercial banks, as they highlight the critical role of these factors in the development of sustainable e-banking practices. Overall, the study provides valuable insights for commercial banks seeking to improve their e-banking services and ensure customer satisfaction. Commercial banks can enhance their competitiveness and achieve sustainable growth in the highly competitive e-banking sector by prioritizing efficiency, reliability, responsiveness, and safety and security.

11.
Sensors (Basel) ; 22(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36433321

RESUMEN

A reverse-offset printed temperature sensor based on interdigitated electrodes (IDTs) has been investigated in this study. Silver nanoparticles (AgNPs) were printed on a glass slide in an IDT pattern by reverse-offset printer. The sensing layer consisted of a sucrose film obtained by spin coating the sucrose solution on the IDTs. The temperature sensor demonstrated a negative temperature coefficient (NTC) with an exponential decrease in resistance as the temperature increased. This trend is the characteristic of a NTC thermistor. There is an overall change of ~2800 kΩ for the temperature change of 0 °C to 100 °C. The thermistor is based on a unique temperature sensor using a naturally occurring biocompatible material, i.e., sucrose. The active sensing material of the thermistor, i.e., sucrose used in the experiments was obtained from extract of Muscovado. Our temperature sensor has potential in the biomedical and food industries where environmentally friendly and biocompatible materials are more suitable for sensing accurately and reliably.


Asunto(s)
Nanopartículas del Metal , Temperatura , Plata , Electrodos , Sacarosa
12.
Cureus ; 14(10): e30330, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36407159

RESUMEN

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with multisystem involvement. It is multifactorial and involves epigenetic, genetic, ecological, and environmental factors. Primarily it leads to activation of both innate and adaptive immunity, which consequently leads to autoreactive B cell activation by T cells and leads to immune complexes deposition in tissues leading to an autoimmune cascade that may be limited to the single organ or can cause a widespread systemic involvement. SLE is heterogeneous in presentation, with a broad spectrum of clinical manifestations ranging from clinically mild self-resolving symptoms to severe life-threatening organ involvement. Clinical and serological heterogeneity are critical features in SLE, posing a significant challenge in its diagnosis. Antinuclear antibodies (ANA) are the telltale serological marker in more than 95% of SLE patients. The improved set of European Alliance of Associations for Rheumatology (EULAR) classification enabled accurate diagnosis of SLE. The treatment focuses on remission, preventing organ damage, and improving the overall quality of life.

13.
Dalton Trans ; 51(38): 14721-14733, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36106445

RESUMEN

The tetranuclear NiII2LnIII2 complexes, [{L'2{Ni(MeOH)(µ-OAc)}2(µ3-MeO)2Ln2}, LnIII = YIII (1), GdIII (2), TbIII (3), and DyIII (4)], were prepared using a Schiff base ligand, H3L [H3L = 3-{(2-hydroxy-3-methoxybenzylidene)amino}-2-(2-hydroxy-3-methoxyphenyl)-2,3-dihydroquinazolin-4(1H)-one, where {L'}3- is the deprotonated open structure of H3L]. X-ray crystallographic analysis of 1-4 revealed that all the complexes crystallized in the orthorhombic (Pbcn) space group, and possessed an isostructural tetranuclear butterfly or defect dicubane like core. Direct current magnetic susceptibility measurements performed on 2-4 revealed that all these complexes show an intramolecular ferromagnetic exchange coupling. Well resolved zero-field out-of-phase signals in ac magnetic susceptibility measurements were observed only in the case of 3 (Ueff = 13.4 K; τ0 = 4.1(7) × 10-7 s). This was attributed to the comparatively strong NiII-TbIII magnetic exchange coupling. DFT and ab initio calculations were carried out on 1-4 to ascertain the nature of the ferromagnetic NiII-LnIII (JNi-Ln) and LnIII-LnIII (JLn-Ln) interactions. Magnetic anisotropy and magnetic relaxation mechanisms were discussed in detail for 3 and 4. Theoretical studies provide a rationale for the slow relaxation of magnetization in 3.

14.
J Inorg Biochem ; 235: 111909, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35810526

RESUMEN

The reaction of 4-(azobenzene)phenylstibonic acid with t-butylphosphonic acid led to the isolation of the tetranuclear oxo-hydroxo antimony cluster of formulae [(4-azobenzene-C6H4Sb)4(OH)4(tBuPO3)6] (C1). The reaction of (p-t-butyl phenyl stibonic acid with phenyl phosphonic acid resulted in the isolation of complex with formulae [(p-t-BuC6H4Sb)4(O)2(PhPO3)4(PhPO3H)4] (C2). Based upon the initial results from docking studies, parent stibonic acids, t-butyl-phenylstibonic acid, p-isopropylphenylstibonic acid, 4-azobenzenephenylstibonic acid, and the derived tetranuclear organoantimonate-phosphonate clusters were screened against different cancer cell lines, various Gram-positive and Gram-Negative bacteria and mycobacteria for possible bioactivity profile.


Asunto(s)
Organofosfonatos , Antibacterianos/farmacología , Antimonio , Bacterias Gramnegativas , Bacterias Grampositivas , Organofosfonatos/farmacología
15.
J Ayub Med Coll Abbottabad ; 34(1): 194-196, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35466652

RESUMEN

Lofgren syndrome an acute form of sarcoidosis constitutes erythema nodosum, bilateral hilar adenopathy and arthralgia or arthritis. Here we present a case of a 28 years old young male patient who is a shopkeeper and farmer by profession admitted to inpatient department with chief complaints of bilateral painful nodules on his shins, low grade fever and pain multiple joints on both sides of the body. Suspicion of the Lofgren syndrome was made upon initial evaluation and patient was admitted to inpatient care facility for necessary comprehensive workup. Radiological findings were consistent with bilateral hilar lymphadenopathy and patient was diagnosed with Lofgren syndrome. Patient was started on non-steroidal inflammatory drugs (NSAIDs) with close observation for improvement in response to treatment. After one weak of treatment in hospital, patient was discharged home when his symptoms started to resolve.


Asunto(s)
Eritema Nudoso , Linfadenopatía , Sarcoidosis , Adulto , Artralgia/diagnóstico , Artralgia/tratamiento farmacológico , Eritema Nudoso/diagnóstico , Eritema Nudoso/tratamiento farmacológico , Fiebre , Humanos , Masculino , Sarcoidosis/diagnóstico , Síndrome
16.
Cureus ; 13(8): e17101, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34527487

RESUMEN

Hypersensitivity reactions occur when a host exhibits an inappropriate or exaggerated response to allergens. Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are examples of such exaggerated responses to various drugs or illnesses. Both conditions affect the skin and mucosal surfaces of the oral cavity, urethra, and conjunctiva to varying degrees. TEN involves more than 30% of the total body surface area as opposed to SJS with less than 10% involvement. Skin biopsy is considered the gold standard for diagnosis; however, obtaining appropriate clinical context at presentation with the history of a potential offending drug can help diagnose the condition in situations where skin biopsy is not feasible. Metronidazole has been rarely reported as the offending agent for TEN/SJS with only two previously reported cases in the literature. We present the third case of TEN secondary to metronidazole and discuss the potential mechanism of action of metronidazole along with its common side effects. Our case adds to the existing literature of this rare clinical presentation and highlights the importance of the judicious use of metronidazole in clinical practice.

17.
Small ; 17(37): e2102602, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34339104

RESUMEN

In this study, high-purity and centimeter-scale bulk Ta2 Ni3 Se8 crystals are obtained by controlling the growth temperature and stoichiometric ratio between tantalum, nickel, and selenium. It is demonstrated that the bulk Ta2 Ni3 Se8 crystals could be effectively exfoliated into a few chain-scale nanowires through simple mechanical exfoliation and liquid-phase exfoliation. Also, the calculation of electronic band structures confirms that Ta2 Ni3 Se8 is a semiconducting material with a small bandgap. A field-effect transistor is successfully fabricated on the mechanically exfoliated Ta2 Ni3 Se8 nanowires. Transport measurements at room temperature reveal that Ta2 Ni3 Se8 nanowires exhibit ambipolar semiconducting behavior with maximum mobilities of 20.3 and 3.52 cm2 V-1 s-1 for electrons and holes, respectively. The temperature-dependent transport measurement (from 90 to 295 K) confirms the carrier transport mechanism of Ta2 Ni3 Se8 nanowires. Based on these characteristics, the obtained 1D vdW material is expected to be a potential candidate for additional 1D materials as channel materials.

18.
Biotechnol Bioeng ; 117(10): 3029-3039, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32568406

RESUMEN

Traditional farm-based products based on livestock are one of the main contributors to greenhouse gas emissions. Cultivated meat is an alternative that mimics animal meat, being produced in a bioreactor under controlled conditions rather than through the slaughtering of animals. The first step in the production of cultivated meat is the generation of sufficient reserves of starting cells. In this study, bovine adipose-derived stem cells (bASCs) were used as starting cells due to their ability to differentiate towards both fat and muscle, two cell types found in meat. A bioprocess for the expansion of these cells on microcarriers in spinner flasks was developed. Different cell seeding densities (1,500, 3,000, and 6,000 cells/cm2 ) and feeding strategies (80%, 65%, 50%, and combined 80%/50% medium exchanges) were investigated. Cell characterization was assessed pre- and postbioprocessing to ensure that bioprocessing did not negatively affect bASC quality. The best growth was obtained with the lowest cell seeding density (1,500 cells/cm2 ) with an 80% medium exchange performed (p < .0001) which yielded a 28-fold expansion. The ability to differentiate towards adipogenic, osteogenic, and chondrogenic lineages was retained postbioprocessing and no significant difference (p > .5) was found in clonogenicity pre- or postbioprocessing in any of the feeding regimes tested.


Asunto(s)
Reactores Biológicos/normas , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Abastecimiento de Alimentos/métodos , Carne/provisión & distribución , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos/métodos , Animales , Bovinos , Recuento de Células , Células Madre Mesenquimatosas/metabolismo
19.
Inorg Chem ; 59(10): 6689-6696, 2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-32343568

RESUMEN

Isolation and structural characterization of novel organoantimony(V)-based oxo clusters are reported. (RSb)4(OH)4(t-BuPO3)6 and (RSb)2(O)(t-BuPO3H)6 independently in the presence of pyridine under solvothermal conditions afford the hexanuclear organoantimonate clusters [(RSb)6(µ3-O)2(µ2-O)6(t-BuPO3)4], where R = p-i-PrC6H4 (1), p-ClC6H4 (2). Further, reaction of organostibonate phosphonate with Ti(OiPr)4 in the presence of pyridine under solvothermal conditions afforded the mixed-metal titanium stibonate hexanuclear clusters [(RSb)2Ti4(µ3-O)2(µ2-O)2(t-BuPO3)4(µ-OCH3)4(OCH3)4], where R = p-i-PrC6H4 (3), p-ClC6H4 (4). Band gap measurements were performed on 1-4. They reveal a remarkable reduction in the band gap on moving from the heavier main-group-based oxo cages (1 and 2) to the titanium-incorporated oxo cages (3 and 4).

20.
Inorg Chem ; 59(1): 741-747, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31876419

RESUMEN

The reaction of organobismuth precursors with trityl-H-phosphinic acid in varying reaction conditions afforded colorless crystals, whose single crystal X-ray characterization revealed the formation of monomer {(Ph3Bi)[(Ph3C)(H)PO2]2}·3/2(CH3CN)2.1/2H2O (1) and butterfly shaped tetranuclear cluster Bi4(µ3-O)2[(Ph3C)(H)(PO2)]8·2CH2Cl2·1/2CH3CN.2H2O (2). The reaction of titanium isopropoxide with two different phosphinic acids trityl-H-phosphinic acid and cycP(O)(OH) led to isolation of cubane type octahedral complex {Ti8(µ2-O)8(µ2-OH)4[(Ph3C)(H)PO2]12}[3C7H8] (3) and hexanuclear complex Ti6(µ2-cycPO2)9(µ2-O)6(µ2-OH)3·4CH3CN·4H2O (4) respectively.

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