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Vinod Kumar Verma,1 Suguna Ratnakar Kamaraju,1 Ravindranath Kancherla,1 Lakshmi K Kona,1 Syed Sultan Beevi,1 Tanya Debnath,1 Shalini P Usha,1 Rammohan Vadapalli,2 Ali Syed Arbab,3 Lakshmi Kiran Chelluri11Department of Transplant Biology, Immunology and Stem Cell Laboratory, Global Hospitals, 2Department of Imageology, Vijaya Radiology Centre, Hyderabad, India; 3Department of Biochemistry and Molecular Biology, Georgia Regents University, Augusta, GA, USAAbstract: Fluorescent magnetic iron oxide nanoparticles have been used to label cells for imaging as well as for therapeutic purposes. The purpose of this study was to modify the approach to develop a nanoprobe for cell selection and imaging with a direct therapeutic translational focus. The approach involves physical coincubation and adsorption of superparamagnetic iron oxide nanoparticle-polyethylene glycol (SPION-PEG) complexes with a monoclonal antibody (mAb) or a set of antibodies. Flow cytometry, confocal laser scanning microscopy, transmission electron microscopy, iron staining, and magnetic resonance imaging were used to assess cell viability, function, and labeling efficiency. This process has been validated by selecting adipose tissue-derived cardiac progenitor cells from the stromal vascular fraction using signal regulatory protein alpha (SIRPA)/kinase domain receptor (KDR) mAbs. These markers were chosen because of their sustained expression during cardiomyocyte differentiation. Sorting of cells positive for SIRPA and KDR allowed the enrichment of cardiac progenitors with 90% troponin-I positivity in differentiation cultures. SPION labeled cardiac progenitor cells (1×105 cells) was mixed with gel and used for 3T magnetic resonance imaging at a concentration, as low as 12.5 µg of iron. The toxicity assays, at cellular and molecular levels, did not show any detrimental effects of SPION. Our study has the potential to achieve moderate to high specific cell selection for the dual purpose of imaging and therapy.Keywords: noninvasive molecular imaging, PEGylated nanoprobe, cardiomyocyte, cytotoxicity, apoptosis

Diamond is a semiconductor material with remarkable structural, thermal, and electronic properties that has garnered significant interest in the field of electronics. Although hydrogen (H) and oxygen (O) terminations are conventionally favored in transistor designs, alternative options, such as silicon (Si) and germanium (Ge), are being explored because of their resilience to harsh processing conditions during fabrication. Density-functional theory was used to examine the non-oxidized and oxidized group-IV (Si and Ge)-terminated diamond (100) surfaces. The (3 × 1) reconstructed surfaces feature an ether configuration and show relative stability compared with the bare surface. Hybrid-functional calculations of the electronic properties revealed reduced fundamental bandgaps (<1 eV) and lower negative electron affinities (NEAs) than those of H-terminated diamond surfaces, which is attributed to the introduction of unoccupied Si (Ge) states and the depletion of negative charges. Furthermore, oxidation of these surfaces enhanced the stability of the diamond surfaces but resulted in two structural configurations: ether and ketone. Oxidized ether configurations displayed insulating properties with energy gaps of ∼4.3 ± 0.3 eV, similar to H-terminated diamond (100) surfaces, whereas bridged ether configurations exhibited metallic properties. Oxidization of the metallic ketone configurations leads to the opening of relatively smaller gaps in the range of 1.1–1.7 eV. Overall, oxidation induced a shift from NEAs to positive electron affinities, except for the reverse-ordered ketone surface with an NEA of −0.94 eV, a value comparable to the H-terminated diamond (100) surfaces. In conclusion, oxidized group-IV-terminated diamond surfaces offer enhanced stability compared to H-terminated surfaces and display unique structural and electronic properties that are influenced by surface bonding. [ABSTRACT FROM AUTHOR]

Nanocrystalline cerium (IV) oxide is a technologically important material due to its high oxygen storage capacity, oxygen ionic conductivity and thermal stability. In this paper we report preparation of nanocrystalline CeO2 using glycerin nitrate method, where the precursor obtained from the mixture of cerium nitrate and glycerin were calcined at temperatures ranging from 200°C to 800°C in steps of 100°C in a muffle furnace. Attempts were also made to prepare nanocrystalline cerium (IV) oxide doped with both Mg and Zr using the same method. The calcined specimens were characterized using XRD, FTIR and SEM/EDX analyses. The influence of the calcination temperature on the cubic phase formation and its consequent effect on the crystallite size of the prepared CeO2 were studied and interpreted. The crystallite sizes calculated from XRD data using Scherrer formula reveal that the phases are nanocrystals, which was further supported by SEM photograph. The apparent activation energy for crystalline coarsening is found to be very low (26.8 kJmol-1) for this precursor compared to reported data. XRD data and also EDX analysis shows that both Mg and Zr could also be doped in CeO2 upto a certain composition, Ce1-x-yMgxZryO2-δ (x = 0.05, y = 0.05). [ABSTRACT FROM AUTHOR]

Nanocrystalline cerium (IV) oxide is a technologically important material due to its high oxygen storage capacity, oxygen ionic conductivity and thermal stability. In this paper we report preparation of nanocrystalline CeO2 using glycerin nitrate method, where the precursor obtained from the mixture of cerium nitrate and glycerin were calcined at temperatures ranging from 200°C to 800°C in steps of 100°C in a muffle furnace. Attempts were also made to prepare nanocrystalline cerium (IV) oxide doped with both Mg and Zr using the same method. The calcined specimens were characterized using XRD, FTIR and SEM/EDX analyses. The influence of the calcination temperature on the cubic phase formation and its consequent effect on the crystallite size of the prepared CeO2 were studied and interpreted. The crystallite sizes calculated from XRD data using Scherrer formula reveal that the phases are nanocrystals, which was further supported by SEM photograph. The apparent activation energy for crystalline coarsening is found to be very low (26.8 kJmol-1) for this precursor compared to reported data. XRD data and also EDX analysis shows that both Mg and Zr could also be doped in CeO2 upto a certain composition, Ce1-x-yMgxZryO2-δ (x = 0.05, y = 0.05). [ABSTRACT FROM AUTHOR]

A series of vanadium substituted potassium hexagonal tungsten bronzes KxVyW1-yO3 (K-HTB) were prepared by conventional solid state method at 800 °C with compositions of x = 0.30 and 0.00≤y≤0.15. A mixture of K-HTB and non bronze phases with y≥0.20 was observed. The proportion of this non bronze phase increases with increasing vanadium content. The non bronze phases in the mixture could not be indexed yet. In contrast, a very small amount of vanadium can be substituted in potassium tetragonal tungsten bronzes (K- TTB) at 800 °C with x = 0.50 and 0.00≤y≤0.02, however at 700 °C vanadium substituted K-TTB can be prepared with 0.00≤≤y0.05. Further substitution of vanadium in K-TTB decomposes to K-HTB and non-bronze phases. [ABSTRACT FROM AUTHOR]

A series of vanadium substituted potassium hexagonal tungsten bronzes KxVyW1-yO3 (K-HTB) were prepared by conventional solid state method at 800 °C with compositions of x = 0.30 and 0.00≤y≤0.15. A mixture of K-HTB and non bronze phases with y≥0.20 was observed. The proportion of this non bronze phase increases with increasing vanadium content. The non bronze phases in the mixture could not be indexed yet. In contrast, a very small amount of vanadium can be substituted in potassium tetragonal tungsten bronzes (K- TTB) at 800 °C with x = 0.50 and 0.00≤y≤0.02, however at 700 °C vanadium substituted K-TTB can be prepared with 0.00≤≤y0.05. Further substitution of vanadium in K-TTB decomposes to K-HTB and non-bronze phases. [ABSTRACT FROM AUTHOR]

Abstract: Series of compositions Bi2(M′ x M 1−x )4O9 with x=0.0, 0.1,…, 1.0 and M′/M=Ga/Al, Fe/Al and Fe/Ga were synthesized by dissolving appropriate amounts of corresponding metal nitrate hydrates in glycerine, followed by gelation, calcination and final heating at 800°C for 24h. The new compositions with M′/M=Ga/Al form solid-solution series, which are isotypes to the two other series M′/M=Fe/Al and Fe/Ga. The XRD data analysis yielded in all cases a linear dependence of the lattice parameters related on x. Rietveld structure refinements of the XRD patterns of the new compounds, Bi2(Ga x Al1−x )4O9 reveal a preferential occupation of Ga in tetrahedral site (4h). The IR absorption spectra measured between 50 and 4000cm−1 of all systems show systematic shifts in peak positions related to the degree of substitution. Samples treated in 18O2 atmosphere (16h at 800°C, 200mbar, 95% 18O2) for 18O/16O isotope exchange experiments show a well-separated IR absorption peak related to the M–18Oc–M vibration, where Oc denotes the common oxygen of two tetrahedral type MO4 units. The intensity ratio of M–18Oc/M–16Oc IR absorption peaks and the average crystal sizes were used to estimate the tracer diffusion coefficients of polycrystalline Bi2Al4O9 (D=2×10−22 m2s−1), Bi2Fe4O9 (D=5×10−21 m2s−1), Bi2(Ga/Al)4O9 (D=2×10−21 m2s−1) and Bi2Ga4O9 (D=2×10−20 m2s−1). [Copyright &y& Elsevier]

Experiments with graphene have demonstrated that 2D van der Waals materials can be stable, robust, and efficiently manipulated at the level of individual atomic planes. However, the stability and manipulation of 1D van der Waals materials and individual atomic chains remains elusive. Here, the ability to exfoliate and process two representative van der Waals materials containing 1D motifs, namely MoI 3 and Ta 2 Se 8 I, at the scale of individual atomic chains is demonstrated. High-resolution transmission electron microscopy and atomic force microscopy studies confirm the presence of stable individual atomic chains of MoI 3 at room temperature. It is further shown that 1D van der Waals materials with low exfoliation energy, such as Ta 2 Se 8 I, can be processed with electron beams to achieve suspended individual atomic chains. Ab initio calculations corroborate the findings regarding the cleavage energies and the thermodynamic stability of individual atomic chains in these 1D van der Waals materials. These results demonstrate that the top-down approach in material processing can be extended to the scale of individual chains., (© 2024 Wiley‐VCH GmbH.)

As reserves of non-renewable energy sources decline, the search for sustainable alternatives becomes increasingly critical. Next-generation energy materials play a key role in this quest by enabling the manipulation of properties for effective energy solutions and understanding interfaces to enhance energy yield. Studying these interfaces is essential for managing charge transport in optoelectronic devices, yet it presents significant challenges. This review emphasizes the critical role of interfaces in kesterite solar cells (KSCs), focusing on interfacial architecture, carrier losses, and non-radiative recombination. This review highlights the importance of addressing interface issues and utilizing advanced characterization tools to reveal interface properties. Current interface problems are addressed, recent advancements in interface engineering are summarized, and perspectives on future challenges and prospects are offered. The goal is to illuminate the nature of interfaces and tackle interface losses, which are crucial for improving device design and performance. Despite their pivotal role in device operation, comprehensive reviews on interfaces are lacking, underscoring the relevance of the work for researchers in material interfaces and device engineering. It is hoped that this article will spark interest and inspire further research into interface studies and the mitigation of interface losses., (© 2024 Wiley‐VCH GmbH.)

Three closely related, aerobic, Gram-stain-negative, motile, rod-shaped bacterial strains (PS-2 T , PS-17, and PS-19) were isolated from the skin of freshwater pufferfish (Tetraodon cutcutia). Colonies are pinkish-colored. The optimum growth occurred at 28-30 °C, and the pH was 6.5-7. The major cellular fatty acids were C16:1 ω7c, iso-C15.0, C17:1 ω8c, C18:1 ω7c, and C16:0. The predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, and amino lipids. The genome size of strain PS-2 T is 4.8 Mbp, and the G + C content was 46.0%. The major fraction of genes were associated with biological processes (45.64%), followed by molecular function (29.86%) and cellular components (24.49%). The unique genes identified in strain PS-2 T secreted cyanophycinase, UDP-N-acetylglucosamine 2-epimerase, methyltransferase, kynureninase, ADA regulatory protein, biphenyl degradation, thermostable carboxypeptidase 1, tetrathionate respiration, etc. In addition, alanine and glutamate racemases were present. The 16S rRNA gene sequences shared 98.83-99.24% similarity with the closely related type strains of Shewanella. The ANI and AAI of strain PS-2 T with reference type strains of the genus Shewanella were below 95-96%, and the corresponding dDDH values were below 70%. A phylogenetic tree based on 16S rRNA gene sequences and genome-wide core genes revealed that strain PS-2 T clustered with Shewanella oneidensis LMG 19005 T in both phylogenetic trees. Based on the polyphasic analysis, the new isolates (PS-2 T , PS-17, and PS-19) represent a novel species of Shewanella, for which Shewanella cutis sp. nov. is proposed. The type strain is PS-2 T (= TBRC 15838 T  = NBRC 115342 T )., (© 2023. Institute of Microbiology, Academy of Sciences of the Czech Republic, v.v.i.)

Taking advantage of the slow exciton-to-dopant energy transfer process, we dissociated the exciton in Mn-doped perovskite via ultrafast electron shuttling to a surface adsorbed 4-nitro phenol molecule. The observed ultrafast electron transfer process is competitive to the ultrafast exciton scattering process (∼140 fs) to the continuum states via optical phonons, but three-orders faster than the exciton-to-Mn energy transfer timescale.

Inspired by biomineralization, the recent incorporation of organic molecules into inorganic lattices shows interesting optical properties and tunability. We functionalize all inorganic CsPbBr 3 perovskite nanocrystals (PNCs) with amino acid (AA) cysteine using the water-hexane interfacial approach. Along with the AA cysteine, we added AuBr 3 salt into the aqueous phase, leading to the formation of a Au-cysteine thiolate complex to activate the aqueous to nonaqueous phase transportation of the AA via a molecular shuttle, oleylamine. The interaction between CsPbBr 3 PNCs and the Au-cysteine thiolate complex is probed using optical spectroscopy, which reveals dimensional reduction of the parent PNCs to form CsPbBr 3 nanoplatelets (NPls) and subsequent phase transformation to CsPb 2 Br 5 NPls. X-ray diffraction, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy conclusively support the above chemical transformation reaction via interfacial chemistry. We propose a mechanistic insight into the dimensional growth in one direction in the presence of AAs via preferential ligand binding to specific facets, leading to transformation from 3D cubes to 2D NPls, while, presumably, the phase transformation occurs via the CsBr stripping mechanism upon prolonged interaction with water. Since AAs are building blocks for several redox-active complex biological moieties, including proteins, investigation of the interaction of AAs with PNCs may be advantageous since the latter can act as a fluorescent probe for bioimaging application., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

(TaSe&#95;{4})&#95;{2}I is a well-studied quasi-one-dimensional compound long-known to have a charge-density wave (CDW) transition around 263 K. We argue that the critical fluctuations of the pinned CDW order parameter near the transition can be inferred from the resistance noise on account of their coupling to the dissipative normal carriers. Remarkably, the critical fluctuations of the CDW order parameter are slow enough to survive the thermodynamic limit and dominate the low-frequency resistance noise. The noise variance and relaxation time show rapid growth (critical opalescence and critical slowing down) within a temperature window of ϵ≈±0.1, where ϵ is the reduced temperature. This is very wide but consistent with the Ginzburg criterion. We further show that this resistance noise can be quantitatively used to extract the associated critical exponents. Below |ϵ|≲0.02, we observe a crossover from mean-field to a fluctuation-dominated regime with the critical exponents taking anomalously low values. The distribution of fluctuations in the critical transition region is skewed and strongly non-Gaussian. This non-Gaussianity is interpreted as the breakdown of the validity of the central limit theorem as the diverging coherence volume becomes comparable to the macroscopic sample size. The large magnitude critical fluctuations observed over an extended temperature range, as well as the crossover from the mean-field to the fluctuation-dominated regime highlight the role of the quasi-one-dimensional character in controlling the phase transition.

Superalkalis are unusual species having ionization energies lower than that of the alkali metals. These species with various applications are of great importance in chemistry due to their low ionization energies and strong reducing property. A typical superalkali contains a central electronegative core decorated with excess metal ligands. In the quest for novel superalkalis, we have designed the superalkalis HLi 2 , HLiNa and HNa 2 using hydrogen as central electronegative atom for the first time employing high level ab initio (CCSD(T), MP2) and density functional theory (ωB97X-D) methods. The superalkalis exhibit very low ionization energies, even lower than that of cesium. Stability of these species is verified from binding energy and dissociation energy values. The superalkalis are capable of reducing SO 2 , NO, CO 2 , CO and N 2 molecules by forming stable ionic complexes and therefore can be used as catalysts for the reduction or activation of systems possessing very low electron affinities. The superalkalis form stable supersalts with tailored properties when interact with a superhalogen. They also show remarkably high non-linear optical responses, hence could have industrial applications. It is hoped that this work will enrich the superalkali family and spur further theoretical and experimental research in this direction., (© 2024 Wiley-VCH GmbH.)

Considering the importance of physics and chemistry at material interfaces, we have explored the coupling of multinary chalcogenide semiconductor Cu 2 NiSnS 4 nanoparticles (CNTS NPs) for the first time with the noble metal (Au) to form Au-CNTS nano-heterostructures (NHSs). The Au-CNTS NHSs is synthesized by a simple facile hot injection method. Synergistic experimental and theoretical approaches are employed to characterize the structural, optical, and electrical properties of the Au-CNTS NHSs. The absorption spectra demonstrate enhanced and broadened optical absorption in the ultraviolet-visible-near-infrared (UV-Vis-NIR) region, which is corroborated by cyclic voltammetry (CV) readings. CV measurements show type II staggered band alignment, with a conduction band offset (CBO) of 0.21 and 0.23 eV at the Au-CNTS/CdS and CNTS/CdS interface, respectively. Complementary first-principles density functional theory (DFT) calculations predict the formation of a stable Au-CNTS NHSs, with the Au nanoparticle transferring its electrons to the CNTS. Moreover, our interface analysis using ultrafast transient absorption experiments demonstrate that the Au-CNTS NHSs facilitates efficient transport and separation of photoexcited charge carriers when compared to pristine CNTS. The transient measurements further reveal a plasmonic electronic transfer from the Au nanoparticle to CNTS. Our advanced analysis and findings will prompt investigations into new functional materials and their photo/electrocatalysis and optoelectronic device applications in the future.

Water-hexane interfacial preparation of photostable Au@CsPbBr 3 (Au@CPB) hybrid nanocrystals (NCs) from pure CsPbBr 3 (CPB) NCs is reported, with the coexistence of exciton and localized surface plasmon resonance with equal dominance. This enables strong exciton-plasmon coupling in these plasmonic perovskite NCs where not only the photoluminescence is quenched intrinsically due to ultrafast charge separation, but also the light absorption property increases significantly, covering the entire visible region. Using a controlled interfacial strategy, a reversible chemical transformation between CPB and Au@CPB NCs is shown, with the simultaneous eruption of larger-size ligand-free aqueous Au nanoparticles (NPs). An adsorption-desorption mechanism is proposed for the reversible transformation, while the overgrowth reaction of the Au NPs passes through the Au aggregation intermediate. This study further shows that the plasmonic Au@CPB hybrid NCs as well as ligand-free Au NPs exhibit clear surface enhanced Raman scattering (SERS) effect of a commercially available probe molecule. Overall, the beautiful interfacial chemistry delivers two independent plasmonic materials, i.e., Au@CPB NCs and ligand-free aqueous Au NPs, which may find important implications in photocatalytic and biomedical applications., (© 2024 Wiley‐VCH GmbH.)

Manganese doping has been demonstrated as a versatile tool to tune the emission of CsPbCl 3 nanocrystals (NCs). Although this has been demonstrated in nanocubes and nanoplatelets, strategies for doping Mn 2+ in size-tunable, excitonic CsPbCl 3 quantum dots (QDs) remain absent. In this work, we demonstrate the synthesis of size-tunable spheroidal CsPbCl 3 :Mn 2+ QDs, which can be obtained by a water-hexane interfacial combined anion and cation exchange strategy starting from CsPbBr 3 QDs. Interestingly, the QDs exhibit a fast 0.2 ms Mn 2+ photoluminescence (PL) lifetime and an energy transfer (ET) time of approximately 100 ps from the excitonic state of the QD to the atomic state of the Mn 2+ ion. The size dependence observation of the manganese PL efficiency and the slow ET rate suggest that Mn 2+ mainly gets incorporated at the QD's surface, highlighting the importance of strategies chosen for the incorporation of Mn 2+ into perovskite QDs.

Lead halide perovskites suffer from water and moisture instability due to the highly ionic nature of the crystal structures, though a few groups took advantage of it for chemical transformation via water-assisted strategy. However, direct exposure of the perovskite to bulk water leads to uncontrolled chemical transformation. Here, we report a controlled chemical transformation of CsPbBr 3 to CsPb 2 Br 5 triggered by nanoconfined water by placing CsPbBr 3 in the nonpolar phase within a reverse micelle. The chemical transformation reaction is probed by using steady-state and time-resolved optical spectroscopy. We observe absorption and photoluminescence in the UV region stemming clearly from the CsPb 2 Br 5 phase upon interaction with the reverse micellar aqueous solution. Transmission electron microscopy and X-ray diffraction measurements further provided the structure and morphology. Our results direct the formation of CsPbBr 3 -CsPb 2 Br 5 nanocomposite under dry conditions while the chemically transformed CsPb 2 Br 5 phase exists only in moist conditions, which we explain via the CsBr-stripping mechanism.

Colon cancer affects people of all ages. However, its frequency, as well as the related morbidity and mortality, are high among older adults. The complex physiological changes in the aging gut substantially limit the development of cancer therapies. Here, we identify a potentially unique intestinal microenvironment that is linked with an increased risk of colon cancer in older adults. Our findings show that aging markedly influenced persistent fucosylation of the apical surfaces of intestinal epithelial cells, which resulted in a favorable environment for tumor growth. Furthermore, our findings shed light on the importance of the host-commensal interaction, which facilitates the dysregulation of fucosylation and promotes tumor growth as people get older. We analyzed colonic microbial populations at the species level to find changes associated with aging that could contribute to the development of colon cancer. Analysis of single-cell RNA-sequencing data from previous publications identified distinct epithelial cell subtypes involved in dysregulated fucosylation in older adults. Overall, our study provides compelling evidence that excessive fucosylation is associated with the development of colon cancer, that age-related changes increase vulnerability to colon cancer, and that a dysbiosis in microbial diversity and metabolic changes in the homeostasis of older mice dysregulate fucosylation levels with age.