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In this article, the mixed convection transport of the Carreau fluid in the presence of a magnetic field and a heated circular cylinder within a trapezoidal cavity is examined. Finite element analysis is used via COMSOL Multiphysics software to simulate the two-dimensional flow. The heat equation is formulated by incorporating the effects of viscous dissipation and Joule heating. The upper and lower surfaces of the cavity are adiabatic, while the left and right sides are assumed to be cold. The temperature distribution and flow field within the cavity are visualized through the plotting of isotherms, streamlines, and total entropy generation. The graphical representations are performed to examine the impacts of physical parameters on temperature, flow field, and total entropy generation, including the Reynolds number , Weissenberg number [Formula: see text], Power law index [Formula: see text], Hartman number [Formula: see text], and Richardson number [Formula: see text] and [Formula: see text]. It is found that the Joule heating and Richardson number are the main reasons to increase the thermal performance within the cavity. The r[Formula: see text] ising values of power law index and Weissenberg numbers caused to reduce the velocity field, irreversible effects and circulation within cavity. While the entropy is augmented by elevating the Eckert and Hartmann numbers. Furthermore, heat transfer improved with the increased magnetic field and Eckert number.

Trans fatty acids are specific unsaturated fats found in processed foods that undergo hydrogenation, leading to hepatic disorders such as metabolic-associated fatty liver disease (MAFLD) and conditions like CVD and CKD. The effects of different food samples containing trans fatty acids (elaidic and oleic acid) on the liver, heart, and kidney through antioxidant enzyme activity were investigated in animal models. Liver function tests (ALT, ALP, AST, and LDH), heart biomarker levels (CPK, TC, HDL, LDL, and triglycerides), and kidney biomarker levels (serum creatinine, blood urea nitrogen, and serum uric acid) were examined in serum of rabbits and the histopathology of liver tissues. Results showed that these biomarkers were more elevated in the Mujahid Ghee group than in the normal control, oleic acid, and Kausar Ghee groups. The concentration of antioxidant markers such as peroxidase, glutathione, catalase, thiobarbituric acid reactive substances, and superoxide dismutase were lower in the Mujahid Ghee group. HPLC showed that Mujahid Ghee had the highest quantified value of elaidic acid among all selected samples. Overall, this study demonstrated that elaidic acid in its purest form aggravated MAFLD in rabbit livers and provoked CVK and CVD.

Introduction: Enterococci are considered less virulent organisms, but have incurred recognition for being notorious for their acquisition and transfer of resistance. The greatest potential threat posed by enterococci is vancomycin resistance. The transfer of enterococcal vancomycin resistance to Staphylococcus aureus has been achieved making scientists apprehensive of its consequences. Aim: To find the prevalence of Vancomycin-Resistant Enterococci (VRE) and to determine the antimicrobial resistance pattern in enterococcal urinary isolates. Materials and Methods: A cross-sectional study was carried out on all urinary samples suspected of Urinary Tract Infection (UTI) received for duration of one year from April 2021 to March 2022 in the Department of Microbiology at Uttar Pradesh University of Medical Sciences, Saifai, Etawah, Uttar Pradesh. Enterococci were isolated and identified with a VITEK-2® COMPACT (bioMérieux) automated system. The antibiotic susceptibility pattern was determined by Kirby-Bauer disc diffusion method. Further, confirmation of VRE was done by Minimum Inhibitory Concentration (MIC) E-test. Results: A total of 128 urinary enterococcal isolates were identified with the male-to-female ratio 1.37:1 and mean age of patients was 37.18±22.64 years. Out of total, 71.87% were identified as Enterococcus faecalis followed by 24.21% Enterococcus faecium and the rare species (4%) including E.durans, E.hirae, E.raffinosus. The prevalence of VRE was found to be 8.6%. Maximum resistance by isolates has been shown against ampicillin, erythromycin, ciprofloxacin, and doxycycline. All isolates were sensitive to linezolid. Nitrofurantoin resistance was observed in 4.34% and 25.80% of E.faecalis and E.faecium isolates respectively. Conclusion: In this study, it was revealed that the emergence of VRE in urinary isolates with antimicrobial resistance was higher among E. faecium. All this puts pressure on strict compliance with a multidimensional approach with collaboration of antibiotic stewardship, educational and surveillance programs.

Background: The role of children in transmitting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is difficult to ascertain and the consequences remain unclear. This is necessary for public health or infection control purposes. The objective of this study was to describe the epidemiological, month-wise trends and clinical characteristics of coronavirus disease 2019 (COVID-19) infection among children in a tertiary care hospital. Materials and Methods: A cross-sectional study was performed on all pediatric samples of suspected cases of SARS-CoV-2 infection. The samples were received from the adjoining districts and our Institution in the Department of Microbiology from June to November 2020. Cases were then confirmed by real-time reverse transcriptase-polymerase chain reaction. Results: Of the total 62,030 pediatric samples tested, 847 (1.3%) were SARS-CoV-2 positive. The majority of positive cases were between the ages of 11–15 years. The median age of confirmed patients was 14 years. The male to female ratio was 1.5:1. Infants represented 1.6% of the positive cases. About 62.1% of all positive cases were asymptomatic. Childhood cases increased from June 2020 and peaked in September 2020 before declining. Conclusion: Children of all ages appeared susceptible to COVID-19 and accounted for a very small proportion of confirmed cases. Mostly, children were found to be asymptomatic. Young children can be important transmitters of SARS-CoV-2 infection in the general population. This population can be important for targeting immunization efforts throughout a rapidly evolving situation. Our findings provide further evidence of the distribution of infection in children and the transmission of SARS-CoV-2.

Entropy is the measure of the amount of energy in any physical system that is not accessible for the useful work, which causes a decrease in a system’s thermodynamic efficiency. The idea of entropy generation analysis plays a vital role in characterizing the evolution of thermal processes and minimizing the impending loss of available mechanical power in thermo-fluid systems from an analytical perspective. It has a wide range of applications in biological, information, and engineering systems, such as transportation, telecommunication, and rate processes. The analysis of the entropy generation of axisymmetric magnetohydrodynamic hybrid nanofluid ( S i O 2 − M o S 2 ) /water flow induced by rotating and stretching cylinder in the presence of heat radiation, ohmic heating, and the magnetic field is focus of this study. Thermal energy transport of hybrid nanofluids is performed by applying the Maxwell model. Heat transport is carried out by using convective boundary condition. The dimensionless ordinary differential equations are acquired by similarity transformations. The numerical solution for these differential equations is obtained by the bvp4c program in MATLAB. A comparison between nanofluid and hybrid nanofluid is made for flow field, temperature, and entropy generation. Comparison of nanofluid flow with hybrid nanofluid flow exhibits a higher rate of heat transmission, while entropy generation exhibits the opposite behavior. It is observed that the flow and heat distribution increase as the solid volume fraction’s value grows. An increase in entropy is indicated by augmentation in the Brinkman number and temperature ratio parameter, but the Bejan number shows a declining trend. Furthermore, outcomes of the Nusselt number for hybrid nanofluid and nanofluid are calculated for various parameters. It is noticed that the Nusselt number is reduced for enlarging the magnetic field and Eckert number. The axial and azimuthal wall stress parameters are declined by augmenting the Reynolds number.

In recent times, enormous progress has been made in improving the diagnosis and therapeutic strategies for breast carcinoma, yet it remains the most prevalent cancer and second highest contributor to cancer-related deaths in women. Breast cancer (BC) affects one in eight females globally. In 2018 alone, 1.4 million cases were identified worldwide in postmenopausal women and 645,000 cases in premenopausal females, and this burden is constantly increasing. This shows that still a lot of efforts are required to discover therapeutic remedies for this disease. One of the major clinical complications associated with the treatment of breast carcinoma is the development of therapeutic resistance. Multidrug resistance (MDR) and consequent relapse on therapy are prevalent issues related to breast carcinoma; it is due to our incomplete understanding of the molecular mechanisms of breast carcinoma disease. Therefore, elucidating the molecular mechanisms involved in drug resistance is critical. For management of breast carcinoma, the treatment decision not only depends on the assessment of prognosis factors but also on the evaluation of pathological and clinical factors. Integrated data assessments of these multiple factors of breast carcinoma through multiomics can provide significant insight and hope for making therapeutic decisions. This omics approach is particularly helpful since it identifies the biomarkers of disease progression and treatment progress by collective characterization and quantification of pools of biological molecules within and among the cancerous cells. The scrupulous understanding of cancer and its treatment at the molecular level led to the concept of a personalized approach, which is one of the most significant advancements in modern oncology. Likewise, there are certain genetic and non-genetic tests available for BC which can help in personalized therapy. Genetically inherited risks can be screened for personal predisposition to BC, and genetic changes or variations (mutations) can also be identified to decide on the best treatment. Ultimately, further understanding of BC at the molecular level (multiomics) will define more precise choices in personalized medicine. In this review, we have summarized therapeutic resistance associated with BC and the techniques used for its management.

Prenatal screening and diagnosis are increasingly becoming a part of medical practice. Prenatal screening can reduce the incidence of birth defects which cause morbidity and mortality in newborns. With emerging technologies, now it is possible to diagnose the genetic basis of birth defects more accurately in the prenatal period for early management. Different approaches are available for detecting genetic defects at different levels like karyotyping, chromosomal microarrays and Sanger sequencing. However, many cases still remain undiagnosed. Next generation sequencing has revolutionized the field of genetics that can detect genetic defects at the level of a single base pair. It includes both whole exome sequencing (WES) and whole genome sequencing (WGS). WES has particularly accelerated the discovery of disease-causing variants in many monogenic anomalies postnatally. Research is being conducted on the use of whole exome sequencing in the prenatal diagnostics of genetic anomalies detected by ultrasound. It is a more efficient way of getting an insight into the molecular basis of birth defects compared with conventional genetic approaches. However, technical and ethical issues need to be addressed before introducing this technique into routine prenatal clinical practice. Fetal cell sampling is done by invasive medical procedures like amniocentesis or chorionic villus sampling. However, noninvasive strategy of collecting fetal DNA from maternal plasma is an exciting and emerging domain. It is evident that in the coming years, we shall be able to use these techniques in the routine clinical setting and to improve the diagnosis and management of birth disorders during prenatal period.

The evolution of nuclear spin state populations is investigated for the case of a 13C2-labeled triyne in solution, for which the near-equivalent coupled pairs of 13C nuclei experience cross-correlated relaxation mechanisms. Inversion-recovery experiments reveal different recovery curves for the main peak amplitudes, especially when the conversion of population imbalances to observable coherences is induced by a radio frequency pulse with a small flip angle. Measurements are performed over a range of magnetic fields by using a sample shuttle apparatus. In some cases, the time constant TS for decay of nuclear singlet order is more than 100 times larger than the time constant T1 for the equilibration of longitudinal magnetization. The results are interpreted by a theoretical model incorporating cross-correlated relaxation mechanisms, anisotropic rotational diffusion, and an external random magnetic field. A Lindbladian formalism is used to describe the dissipative dynamics of the spin system in an environment of finite temperature. Good agreement is achieved between theory and experiment., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

Despite the importance of rhodium complexes in catalysis, and the favorable 100% natural abundance of the spin-1/2 103Rh nucleus, there are few reports of 103Rh nuclear magnetic resonance (NMR) parameters in the literature. In part, this is the consequence of the very low gyromagnetic ratio of 103Rh and its dismal NMR sensitivity. In a previous paper [Harbor-Collins et al., J. Chem. Phys. 159, 104 307 (2023)], we demonstrated an NMR methodology for 1H-enhanced 103Rh NMR and demonstrated an application to the 103Rh NMR of the dirhodium formate paddlewheel complex. In this paper, we employ selective 18O labeling to break the magnetic equivalence of the 103Rh spin pair of dirhodium formate. This allows the estimation of the 103Rh-103Rh spin-spin coupling and provides access to the 103Rh singlet state. We present the first measurement of a 18O-induced 103Rh secondary isotope shift as well as the first instance of singlet order generated in a 103Rh spin pair. The field-dependence of 103Rh singlet relaxation is measured by field-cycling NMR experiments., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

The nuclear magnetic resonance (NMR) spectroscopy of spin-1/2 nuclei with low gyromagnetic ratio is challenging due to the low NMR signal strength. Methodology for the rapid acquisition of 103Rh NMR parameters is demonstrated for the case of the rhodium formate "paddlewheel" complex Rh2(HCO2)4. A scheme is described for enhancing the 103Rh signal strength by polarization transfer from 1H nuclei, which also greatly reduces the interference from ringing artifacts, a common hurdle for the direct observation of low-γ nuclei. The 103Rh relaxation time constants T1 and T2 are measured within 20 min by using 1H-detected experiments. The field dependence of the 103Rh T1 is measured. The high-field relaxation is dominated by the chemical shift anisotropy mechanism. The 103Rh shielding anisotropy is found to be very large: |Δσ| = 9900 ± 540 ppm. This estimate is compared with density functional theory calculations., (© 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

The Aharonov-Anandan phase is a contribution to the phase acquired by the cyclic evolution of a quantum state, which depends only on the geometric properties of its trajectory. We report the study and the exploitation of the Aharonov-Anandan phase by nuclear magnetic resonance interferometry techniques in homonuclear spin-1/2 pairs in the near-equivalence limit. We introduce a new method for engineering effective zero-quantum Hamiltonians with an arbitrary phase in the transverse plane. We use this method to generate a variety of cyclic zero-quantum paths, enabling direct study of the geometric Aharonov-Anandan phase to probe the rotational characteristics of the zero-quantum subspace. We show that the geometric Aharonov-Anandan phase may be used for efficient double-quantum excitation in strongly coupled spin pairs. We find that geometric double-quantum excitation outperforms the standard method by a factor of 2 in experiments performed on a typical case involving near-equivalent spin pairs.

Nuclear spin relaxation mechanisms are often difficult to isolate and identify, especially in molecules with internal flexibility. Here we combine experimental work with computation in order to determine the major mechanisms responsible for 31 P spin-lattice and singlet order (SO) relaxation in pyrophosphate, a physiologically relevant molecule. Using field-shuttling relaxation measurements (from 2 μT to 9.4 T) and rates calculated from molecular dynamics (MD) trajectories, we identified chemical shift anisotropy (CSA) and spin-rotation as the major mechanisms, with minor contributions from intra- and intermolecular coupling. The significant spin-rotation interaction is a consequence of the relatively rapid rotation of the -PO 3 2- entities around the bridging P-O bonds, and is treated by a combination of MD simulations and quantum chemistry calculations. Spin-lattice relaxation was predicted well without adjustable parameters, and for SO relaxation one parameter was extracted from the comparison between experiment and computation (a correlation coefficient between the rotational motion of the groups).

Coupled pairs of spin-1/2 nuclei support one singlet state and three triplet states. In many circumstances, the nuclear singlet order, defined as the difference between the singlet population and the mean of the triplet populations, is a long-lived state that persists for a relatively long time in solution. Various methods have been proposed for generating singlet order, starting from nuclear magnetization. This requires the stimulation of singlet-to-triplet transitions by modulated radiofrequency fields. We show that a recently described pulse sequence, known as PulsePol [Schwartz et al., Sci. Adv., 4, eaat8978 (2018)], is an efficient technique for converting magnetization into long-lived singlet order. We show that the operation of this pulse sequence may be understood by adapting the theory of symmetry-based recoupling sequences in magic-angle-spinning solid-state nuclear magnetic resonance (NMR). The concept of riffling allows PulsePol to be interpreted by using the theory of symmetry-based pulse sequences and explains its robustness. This theory is used to derive a range of new pulse sequences for performing singlet-triplet excitation and conversion in solution NMR. Schemes for further enhancing the robustness of the transformations are demonstrated.

Synthesis of Kr@C 60 is achieved by quantitative high-pressure encapsulation of the noble gas into an open-fullerene, and subsequent cage closure. Krypton is the largest noble gas entrapped in C 60 using 'molecular surgery' and Kr@C 60 is prepared with >99.4% incorporation of the endohedral atom, in ca. 4% yield from C 60 . Encapsulation in C 60 causes a shift of the 83 Kr resonance by -39.5 ppm with respect to free 83 Kr in solution. The 83 Kr spin-lattice relaxation time T 1 is approximately 36 times longer for Kr encapsulated in C 60 than for free Kr in solution. This is the first characterisation of a stable Kr compound by 83 Kr NMR.

The nuclear magnetic resonance (NMR) spectra of spin-1/2 pairs contain four peaks, with two inner peaks much stronger than the outer peaks in the near-equivalence regime. We have observed that the strong inner peaks have significantly different linewidths when measurements were performed on a 13 C 2 -labelled triyne derivative. This linewidth difference may be attributed to strong cross-correlation effects. We develop the theory of cross-correlated relaxation in the case of near-equivalent homonuclear spin-1/2 pairs, in the case of a molecule exhibiting strongly anisotropic rotational diffusion. Good agreement is found with the experimental NMR lineshapes.

Nuclear spin singlet states are often found to allow long-lived storage of nuclear magnetization, which can form the basis of novel applications in spectroscopy, imaging, and in studies of dynamic processes. Precisely how long such polarization remains intact, and which factors affect its lifetime is often difficult to determine and predict. We present a combined experimental/computational study to demonstrate that molecular dynamics simulations and ab initio calculations can be used to fully account for the experimentally observed proton singlet lifetimes in ethyl-d 5 -propyl-d 7 -maleate in deuterated chloroform as solvent. The correspondence between experiment and simulations is achieved without adjustable parameters. These studies highlight the importance of considering unusual and difficult-to-control mechanisms, such as dipolar couplings to low-gamma solvent nuclei, and to residual paramagnetic species, which often can represent lifetime limiting factors. These results also point to the power of molecular dynamics simulations to provide insights into little-known NMR relaxation mechanisms.

The population imbalance between nuclear singlet states and triplet states of strongly coupled spin-1/2 pairs, also known as nuclear singlet order, is well protected against several common relaxation mechanisms. We study the nuclear singlet relaxation of 13 C pairs in aqueous solutions of 1,2- 13 C 2 squarate over a range of pH values. The 13 C singlet order is accessed by introducing 18 O nuclei in order to break the chemical equivalence. The squarate dianion is in chemical equilibrium with hydrogen-squarate (SqH - ) and squaric acid (SqH 2 ) characterized by the dissociation constants pK 1 = 1.5 and pK 2 = 3.4. Surprisingly, we observe a striking increase in the singlet decay time constants T S when the pH of the solution exceeds ∼10, which is far above the acid-base equilibrium points. We derive general rate expressions for chemical-exchange-induced nuclear singlet relaxation and provide a qualitative explanation of the T S behavior of the squarate dianion. We identify a kinetic contribution to the singlet relaxation rate constant, which explicitly depends on kinetic rate constants. Qualitative agreement is achieved between the theory and the experimental data. This study shows that infrequent chemical events may have a strong effect on the relaxation of nuclear singlet order.

A variety of pulse sequences have been described for converting nuclear spin magnetisation into long-lived singlet order for nuclear spin-1/2 pairs. Existing sequences operate well in two extreme parameter regimes. The magnetisation-to-singlet (M2S) pulse sequence performs a robust conversion of nuclear spin magnetisation into singlet order in the near-equivalent limit, meaning that the difference in chemical shift frequencies of the two spins is much smaller than the spin-spin coupling. Other pulse sequences operate in the strong-inequivalence regime, where the shift difference is much larger than the spin-spin coupling. However both sets of pulse sequences fail in the intermediate regime, where the chemical shift difference and the spin-spin coupling are roughly equal in magnitude. We describe a generalised version of M2S, called gM2S, which achieves robust singlet order excitation for spin systems ranging from the near-equivalence limit well into the intermediate regime. This closes an important gap left by existing pulse sequences. The efficiency of the gM2S sequence is demonstrated numerically and experimentally for near-equivalent and intermediate-regime cases.

Some nuclear spin systems support long-lived states, which display greatly extended relaxation times relative to the relaxation time of nuclear spin magnetization. In spin-1/2 pairs, such a long-lived state is given by singlet order, representing the difference of the population of the nuclear singlet state and the mean population of the three triplets. In many cases, the experiments with long-lived singlet order are very time-consuming because of the need to wait for singlet order decay before the experiment can be repeated; otherwise, spin order remaining from a previous measurement may lead to experimental artifacts. Here, we propose techniques for fast and efficient singlet order destruction. These methods exploit coherent singlet-triplet conversion; in some cases, multiple conversion steps are introduced. We demonstrate that singlet order destruction enables a dramatic reduction of the waiting time between consecutive experiments and suggest to use this approach in singlet-state Nuclear Magnetic Resonance (NMR) experiments with nearly equivalent spins.

Background: Limited reports exist about intracranial incidental findings on computed tomography (CT) imaging. We studied the frequency of incidental findings on 3000 brain CT scans of trauma patients., Methods: Three thousands standard brain CT scans of trauma patients were evaluated for some incidental findings. Cisterna magna was evaluated in 1500 CT scans., Results: In this study we found 30 incidental abnormalities that include 8 cases of tumor: 3 meningioma, 2 craniopharyngioma, 1 oligodendroglioma, 1 low-grade astrocytoma, and 1 medulloblastoma. Suspect osteoma was found in 3 cases. In 3 cases, abnormal calcification was found in pineal region, basal ganglia, and temporal horn area. Three suspect lipomas were found in midline and near midline of the brain. Arachnoid cyst was found in 7 cases and hydrocephaly in 3 cases. Large cisterna magna (>10 cm(3)) was found in 11 cases., Conclusion: Cisterna magna enlargement was the most common incidental finding and brain tumor and arachnoid cyst were next in frequency.

Vascular factors may play a role in the etiology of Alzheimer's disease (AD) and increased serum apolipoprotein E (APOE) levels in AD could be of interest, as APOE concentration is associated with vascular disease. Aims of this study were to evaluate the influence of APOE genotype on serum APOE levels, and, secondly, to study serum APOE concentrations in relation to age and AD. APOE genotypes, serum total cholesterol, LDL cholesterol, HDL cholesterol, total cholesterol/HDL cholesterol ratio, triglycerides, and serum APOE were performed on 52 healthy centenarians, 49 AD patients, 45 age-matched controls, and 72 young healthy adults. In all study population a significant trend in reduction of serum APOE levels from APOE epsilon2- to epsilon4 carriers was observed. The difference in serum APOE levels among age groups significantly decreased in epsilon4 carriers only, including HDL cholesterol; no significant differences between AD patients and age-matched controls were found. In these highly selected populations, APOE genotype distribution strongly influences serum APOE concentration, not suggesting, at present, a possible role as a biochemical marker for AD, but only as a putative longevity factor.