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There is an increasing desire to utilize complex functional electronic materials such as ferroelectrics in next-generation microelectronics. As new materials are considered or introduced in this capacity, an understanding of how we can process these materials into those devices must be developed. Here, the effect of different fabrication processes on the ferroelectric and related properties of prototypical metal oxide (SrRuO3)/ferroelectric (BaTiO3)/metal oxide (SrRuO3) heterostructures is explored. Two different types of etching processes are studied, namely, wet etching of the top SrRuO3 using a NaIO4 solution and dry etching using an Ar+-ion beam (i.e., ion milling). Polarization-electric-field hysteresis loops for capacitors produced using both methods are compared. For the ion-milling process, it is found that the Ar+ beam can introduce defects into the SrRuO3/BaTiO3/SrRuO3 devices and that the milling depth strongly influences the defect level and can induce a voltage imprint on the function. Realizing that such processing approaches may be necessary, work is performed to ameliorate the imprint of the hysteresis loops via ex situ “healing” of the process-induced defects by annealing the ferroelectric material in a barium-and-oxygen-rich environment via a chemical-vapor-deposition-style process. This work provides a pathway for the nanoscale fabrication of these candidate materials for next-generation memory and logic applications.

The recent discovery of polar topological structures has opened the door for exciting physics and emergent properties. There is, however, little methodology to engineer stability and ordering in these systems, properties of interest for engineering emergent functionalities. Notably, when the surface area is extended to arbitrary thicknesses, the topological polar texture becomes unstable. Here we show that this instability of the phase is due to electrical coupling between successive layers. We demonstrate that this electrical coupling is indicative of an effective screening length in the dielectric, similar to the conductor-ferroelectric interface. Controlling the electrostatics of the superlattice interfaces, the system can be tuned between a pure topological vortex state and a mixed classical-topological phase. This coupling also enables engineering coherency among the vortices, not only tuning the bulk phase diagram but also enabling the emergence of a 3D lattice of polar textures.

Interlayer coupling in materials, such as exchange interactions at the interface between an antiferromagnet and a ferromagnet, can produce exotic phenomena not present in the parent materials. While such interfacial coupling in magnetic systems is widely studied, there is considerably less work on analogous electric counterparts (i.e., akin to electric "exchange-bias-like" or "exchange-spring-like" interactions between two polar materials) despite the likelihood that such effects can also engender new features associated with anisotropic electric dipole alignment. Here, electric analogs of such exchange interactions are reported, and their physical origins are explained for bilayers of in-plane polarized Pb1-x Srx TiO3 ferroelectrics. Variation of the strontium content and thickness of the layers provides for deterministic control over the switching properties of the bilayer system resulting in phenomena analogous to an exchange-spring interaction and, leveraging added control of these interactions with an electric field, the ability to realize multistate-memory function. Such observations not only hold technological promise for ferroelectrics and multiferroics but also extend the similarities between ferromagnetic and ferroelectric materials to include the manifestation of exchange-interaction-like phenomena.

Topologically protected polar textures have provided a rich playground for the exploration of novel, emergent phenomena. Recent discoveries indicate that ferroelectric vortices and skyrmions not only host properties markedly different from traditional ferroelectrics, but also that these properties can be harnessed for unique memory devices. Using a combination of capacitor-based capacitance measurements and computational models, it is demonstrated that polar vortices in dielectric-ferroelectric-dielectric trilayers exhibit classical ferroelectric bi-stability together with the existence of low-field metastable polarization states. This behavior is directly tied to the in-plane vortex ordering, and it is shown that it can be used as a new method of non-destructive readout-out of the poled state.

Antiferroelectrics, which undergo a field-induced phase transition to ferroelectric order that manifests as double-hysteresis polarization switching, exhibit great potential for dielectric, electromechanical, and electrothermal applications. Compared to their ferroelectric cousins, however, considerably fewer efforts have been made to understand and control antiferroelectrics. Here, it is demonstrated that the polarization switching behavior of an antiferroelectric can be strongly influenced and effectively regulated by point defects. In films of the canonical antiferroelectric PbZrO3 , decreasing oxygen pressure during deposition (and thus increasing adatom kinetic energy) causes unexpected "ferroelectric-like" polarization switching although the films remain in the expected antiferroelectric orthorhombic phase. This "ferroelectric-like" switching is correlated with the creation of bombardment-induced point-defect complexes which pin the antiferroelectric-ferroelectric phase boundaries, and thus effectively delay the phase transition under changing field. The effective pinning energy is extracted via temperature-dependent switching-kinetics studies. In turn, by controlling the concentration of defect complexes, the dielectric tunability of the PbZrO3 can be adjusted, including being able to convert between "positive" and "negative" tunability near zero field. This work reveals the important role and strong capability of defects to engineer antiferroelectrics for new performance and functionalities.

The potential for creating hierarchical domain structures, or mixtures of energetically degenerate phases with distinct patterns that can be modified continually, in ferroelectric thin films offers a pathway to control their mesoscale structure beyond lattice-mismatch strain with a substrate. Here, it is demonstrated that varying the strontium content provides deterministic strain-driven control of hierarchical domain structures in Pb1- x Srx TiO3  solid-solution thin films wherein two types, c/a and a1 /a2 , of nanodomains can coexist. Combining phase-field simulations, epitaxial thin-film growth, detailed structural, domain, and physical-property characterization, it is observed that the system undergoes a gradual transformation (with increasing strontium content) from droplet-like a1 /a2  domains in a c/a domain matrix, to a connected-labyrinth geometry of c/a domains, to a disconnected labyrinth structure of the same, and, finally, to droplet-like c/a domains in an a1 /a2  domain matrix. A relationship between the different mixed-phase modulation patterns and its topological nature is established. Annealing the connected-labyrinth structure leads to domain coarsening forming distinctive regions of parallel c/a and a1 /a2  domain stripes, offering additional design flexibility. Finally, it is found that the connected-labyrinth domain patterns exhibit the highest dielectric permittivity.

The dynamics of complex topological defects in ferroelectric materials is explored using automated experimentation in piezoresponse force microscopy. Specifically, a complex trigger system (i.e., "FerroBot") is employed to study metastable domain-wall dynamics in Pb0.6Sr0.4TiO3 thin films. Several regimes of superdomain wall dynamics have been identified, including smooth domain-wall motion and significant reconfiguration of the domain structures. We have further demonstrated that microscopic mechanisms of the domain-wall dynamics can be identified; i.e., domain-wall bending can be separated from irreversible domain reconfiguration regimes. In conjunction, phase-field modeling was used to corroborate the observed mechanisms. As such, the observed superdomain dynamics can provide a model system for classical ferroelectric dynamics, much like how colloidal crystals provide a model system for atomic and molecular systems.

[Display omitted] • Techno-functionality of imported R. ferrugineus (Sago grub) larvae protein extracts are reported. • Total essential amino acid (EAA) content of sago grub protein extract SGPE is 223.2 mg/g protein. • Sago grub protein extract displayed five distinct peaks for the FTIR spectrum. • Stable foams (88.8 % after 120 min) were obtained for sago grub protein extracts. • Emulsion capacities (96.8 %) were stable after 60 min the protein extracts. The present study investigated nutritional composition and techno-functional properties of Rhynchophorus ferrugineus larvae (sago grubs) protein extract (SGPE). The fat, carbohydrate, and protein contents of sago grubs were 58.79 %, 18.67 %, and 15.65 %, respectively. SGPE exhibited an isoelectric pH of ∼ 4 based on alkaline solubilisation and pH precipitation. Total essential amino acid (EAA) content and essential amino acid index (EAAI) of SGPE were 223.2 mg/g protein and 0.84 respectively. SDS-PAGE of SGPE displayed proteins in the 10–110 kDa molecular weight range, with substantial protein bands < 20 kDa. As expected for a protein extract, FTIR analysis of SGPE indicated five distinct regions (amides I, II, III, and amide A and B peaks). Techno-functional analysis of SGPE indicated a high foaming capacity (87.3 %) and emulsion stability (96.8 % after 60 min). Heat coagulation of SGPE was higher at pH 7.0 (19.5 %) than that at the pI of 4.0 (4.83 %), corroborating the pH-solubility profile, and relatively high surface hydrophobicity (294.5). The heat enthalpy of the SGPE (59.8 J/g) was lower than that reported for H. illucens and A. cordifera. These findings demonstrate the suitability of SGPE for food technology applications in relation to to the reported techno-functional properties and amino acid profiles. [ABSTRACT FROM AUTHOR]

[Display omitted] • T. molitor and H. illucens larvae had high lipid contents (respectively 28.8% and 42.6%). • H. illucens larvae fats had a desirable ω6:ω3 ratio (3.25) than T. molitor (23.9). • T. molitor larvae fat had better lipid nutritional indices, e.g., HPI, IA, IT, HH. • PUFA in H. illucens larvae fat were mostly concentrated on the sn -1,3 positions. • Both larvae fat showed differences in thermal stability based on fatty acid profile. The fatty acid (FA) profile, nutritional index, and thermal properties of lipids from Tenebrio molitor and Hermetia illucens larvae were studied. T. molitor and H. illucens larvae had high lipid contents (respectively 28.8% and 42.6%), saturated (25.0% and 55.8%), monounsaturated (MUFA) (39.2% and 28.3%), and polyunsaturated (PUFA) fatty acids (35.8% and 15.9%). Both larvae fats contained beneficial ω-3, ω-6, and ω-9 FA. For T. molitor and H. illucens , the lipid nutritional indices were atherogenicity indices 0.68 and 2.75, thrombogenicity indices 0.58 and 0.74, and health-promoting indices 3.51 and 0.80 hypocholesterolemic/hypercholesterolemic acid ratio 1.38 and 0.23, suggesting the nutritional superiority of T. molitor larvae fat. Regioisomeric distribution analysis showed that PUFA in H. illucens larvae fat are concentrated on the sn -1,3 positions, whereas those in T. molitor larvae fat are distributed in all three positions. The thermal stability and crystallisation profiles differed for both larvae fats and demonstrated their potential use in thermally processed foods. [ABSTRACT FROM AUTHOR]

The goals of the present targeted review on maternal and child overweight and obesity were to: (i) understand the current situation in low- and middle-income countries (LMIC) with regard to recent trends and context-specific risk factors; and (ii) building off this, identify entry points for leveraging existing undernutrition programmes to address overweight and obesity in LMIC. Trends reveal that overweight and obesity are a growing problem among women and children in LMIC; as in Ghana, Kenya, Niger, Sierra Leone, Tanzania and Zimbabwe, where the prevalence among urban women is approaching 50 %. Four promising entry points were identified: (i) the integration of overweight and obesity into national nutrition plans; (ii) food systems (integration of food and beverage marketing regulations into existing polices on the marketing of breast-milk substitutes and adoption of policies to promote healthy diets); (iii) education systems (integration of nutrition into school curricula with provision of high-quality foods through school feeding programmes); and (iv) health systems (counselling and social and behaviour change communication to improve maternal diet, appropriate gestational weight gain, and optimal infant and young child feeding practices). We conclude by presenting a step-by-step guide for programme officers and policy makers in LMIC with actionable objectives to address overweight and obesity.

The exotic polarization configurations of topologically protected dipolar textures have opened new avenues for realizing novel phenomena absent in traditional ferroelectric systems. While multiple recent studies have revealed a diverse array of emergent properties in such polar topologies, the details of their atomic and mesoscale structures remain incomplete. Through atomic- and meso-scale imaging techniques, the emergence of a macroscopic ferroelectric polarization along both principal axes of the vortex lattice while performing phase-field modeling to probe the atomic scale origins of these distinct polarization components is demonstrated. Additionally, due to the anisotropic epitaxial strain, the polarization switching behavior perpendicular and parallel to the vortices is highly anisotropic, with switching along the vortex axes occurring over numerous decades in field-pulse width. This slow switching process allows for the deterministic control of the polarization state, enabling a non-volatile, multi-state memory with excellent distinguishability and long retention times., (© 2024 Wiley‐VCH GmbH.)

The discovery of polar vortices and skyrmions in ferroelectric-dielectric superlattices [such as (PbTiO 3 ) n /(SrTiO 3 ) n ] has ushered in an era of novel dipolar topologies and corresponding emergent phenomena. The key to creating such emergent features has generally been considered to be related to counterpoising strongly polar and non-polar materials thus creating the appropriate boundary conditions. This limits the utility these materials can have, however, by rendering (effectively) half of the structure unresponsive to applied stimuli. Here, using advanced thin-film deposition and an array of characterization and simulation approaches, polar vortices are realized in all-ferroelectric trilayers, multilayers, and superlattices built from the fundamental building block of (PbTiO 3 ) n /(Pb x Sr 1- x TiO 3 ) n wherein in-plane ferroelectric polarization in the Pb x Sr 1- x TiO 3 provides the appropriate boundary conditions. These superlattices exhibit substantially enhanced electromechanical and ferroelectric responses in the out-of-plane direction that arise from the ability of the polarization in both layers to rotate to the out-of-plane direction under field. In the in-plane direction, the layers are found to be strongly coupled during switching and when heterostructured with ferroelectric-dielectric building blocks, it is possible to produce multistate switching. This approach expands the realm of systems supporting emergent dipolar texture formation and does so with entirely ferroelectric materials thus greatly improving their responses., (© 2024 Wiley‐VCH GmbH.)

The serum levels of iron, zinc and copper in patients with leukoplakia, oral submucous fibrosis (OSMF) and oral squamous cell carcinoma (OSCC) and compare them with normal subjects is of interest to dentists. The effort was to determine a parameter that will aid the initial diagnosis, a more efficient therapy plan, and ultimately a better prognosis. Participants in the study comprised 40 healthy normal volunteers, 60 patients diagnosed with leukoplakia, 60 patients diagnosed with OSCC, and 60 patients diagnosed with OSMF. After fasting for the whole night, blood samples were taken from each participant. There was analysis by inductively coupled plasma-optical emission spectrometry (ICP-OES) for the determination of trace elements; iron, copper, and zinc. The serum levels of iron and zinc in normal subjects was greater as compared to patients with leukoplakia, OSMF and OSCC. There was increase in serum copper levels in patients with oral leukoplakia, OSMF and OSCC as compared with normal subjects., (© 2024 Biomedical Informatics.)

Introduction Fingerprints found at the crime scene are important and valuable evidence, as they are unique to every individual. Determining the blood group from the blood samples obtained at the site of the crime helps in identifying a person. However, where blood stains are not available, saliva obtained at the crime site can be used to identify the victim. Since fingerprint patterns and blood groups are unique to every individual and remain unchanged throughout life, the correlation between dermatoglyphics and blood groups can be of use in victim identification. Objectives The present study is conducted with the objective of finding out if there is any association between the distribution of fingerprint patterns and blood groups and if this association is of use in gender identification. Materials and method Fingerprint patterns were determined in 200 (females: n = 152, males: n = 48) dental undergraduate students in the age range of 18 to 24 years. ABO blood grouping was done on saliva by using the absorption-elution method. To determine the accuracy of ABO blood group determination using saliva, it was correlated with the ABO blood grouping in blood.  Observations and result The most common fingerprint pattern was found to be loops (87, 43.50%), followed by whorls (81, 40.50%) and arches (32, 16.00%). The most common blood group was B (68, 34%), followed by O (46, 23%) and A (42, 21%), and the least common was AB (12, 6%). A higher percentage of secretors in saliva was observed in females (130, 86%) than males (38, 79%). The correlation of gender with blood group and fingerprint pattern showed that in males, the most common blood group was B (20, 42%), and the most common fingerprint pattern was whorls (21, 44%). In females, the most common blood group was B (48, 32%), while the most common fingerprint pattern was loop (68, 45%). Conclusion Present study reports an association between blood group and dermatoglyphics, which may help in gender identification. Saliva can be used as a helpful tool in victim identification in cases where blood stains are not available., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Deshpande et al.)

Background: Oral lichen planus (OLP), an immune mediated disorder, has been recognized since 1869 and is presented as any one of the six variants. Reticular and erosive are the most frequently encountered. Its proliferative capacity can give some information regarding its progression. We adopted the argyrophilic nucleolar organizer regions (AgNORs) method because of its simplicity to use and dependable results. We evaluated AgNORs in basal, suprabasal, and squamous cell layers. We also compared these three layers within two variants, reticular, and erosive., Materials and Methods: Thirty clinically diagnosed patients of OLP were included in the study. Reticular and erosive variants were included in our study. This was followed by hematoxylin and eosin staining and later by the AgNOR method. The mean number of AgNORs per nucleus was calculated., Results: Thirteen males and 17 females were the gender distribution. Twenty-three (76.67%) had reticular pattern and seven (23.33%) had erosive pattern. The basal cell layer had the highest mean AgNOR compared to suprabasal and squamous layers. Even among, erosive and reticular variants, the former had higher mean AgNOR counts., Discussion: Our results suggest that the inflammatory infiltrate close to the epithelial cells can alter the proliferation index for the pattern of protein synthesis of these cells. Moreover, the high proliferative index in OLP can be related to a specific immunologic response., Conclusion: We conclude that AgNOR can be used as a proliferative marker in earlier lesions to detect the severity., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Journal of Microscopy and Ultrastructure.)

The potential for creating hierarchical domain structures, or mixtures of energetically degenerate phases with distinct patterns that can be modified continually, in ferroelectric thin films offers a pathway to control their mesoscale structure beyond lattice-mismatch strain with a substrate. Here, it is demonstrated that varying the strontium content provides deterministic strain-driven control of hierarchical domain structures in Pb 1- x Sr x TiO 3  solid-solution thin films wherein two types, c/a and a 1 /a 2 , of nanodomains can coexist. Combining phase-field simulations, epitaxial thin-film growth, detailed structural, domain, and physical-property characterization, it is observed that the system undergoes a gradual transformation (with increasing strontium content) from droplet-like a 1 /a 2  domains in a c/a domain matrix, to a connected-labyrinth geometry of c/a domains, to a disconnected labyrinth structure of the same, and, finally, to droplet-like c/a domains in an a 1 /a 2  domain matrix. A relationship between the different mixed-phase modulation patterns and its topological nature is established. Annealing the connected-labyrinth structure leads to domain coarsening forming distinctive regions of parallel c/a and a 1 /a 2  domain stripes, offering additional design flexibility. Finally, it is found that the connected-labyrinth domain patterns exhibit the highest dielectric permittivity., (© 2022 Wiley-VCH GmbH.)

Ameloblastoma is an odontogenic tumour derived from the remnants of odontogenic epithelium. Ameloblastoma shows versatile clinical and histological variants. Basal cell ameloblastoma is a rare variant among all histopathological variants of ameloblastoma. We present a case of a 25-year-old male patient with painless swelling on the lower left side of the face for 1 year, which had gradually increased in size and histologically showed features of basal cell ameloblastoma. The aim of the present paper is to understand this rare variant of ameloblastoma and review the literature., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Journal of Oral and Maxillofacial Pathology.)

Background: Pleomorphic adenoma (PA) and adenoid cystic carcinoma (ADCC) are benign and malignant salivary gland tumors, respectively, with distinct behavior. They have similar origins and cell components. E-cadherins are the main homophilic cell adhesion molecules, which play a central role in maintaining epithelial integrity, functioning in intercellular adhesion and differentiation. Hence, changes in E-cadherin function are reflected in the morphologic events associated with the cellular arrangement, movement and wound healing., Aim: To study and compare the expression of E-cadherin immunostaining in PA and ADCC., Materials and Methods: Fifteen cases of each PA and ADCC were immunohistochemically stained with E-cadherin. Five cases of normal salivary gland tissues were taken as the positive control.Mann-Whitney U -test was used for statistical analysis., Results: About 86.6% of PA cases showed homogeneous staining. 66.6% of cases of ADCC showed heterogeneous staining. PA, cribriform and tubular patterns of ADCC predominantly showed moderate immune-staining and solid patterns of ADCC exhibited predominantly mild immunostaining. Depending on the intensity of staining, we found a significant P value between PA and the solid variant of ADCC., Conclusion: E-cadherin proved to be a better marker for epithelial phenotypes in PAs. In ADCC difference in staining intensity between different histological subtypes suggests that further studies should be done to assess the usefulness of an immuno-marker to know the aggressive behavior of ADCC., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Journal of Oral and Maxillofacial Pathology.)

The clinical presentation of diffuse pigmentation can be alarming to the patient as well as the clinician. A histopathologic examination of a pigmented lesion is necessary in most of the cases in the oral cavity. Oral melanoacanthoma is a very rare diffuse pigmentation with no specific treatment required. It shows increased number of dendritic melanocytes in an acanthotic epithelium. We present a rare case of diffuse pigmentation in the oral cavity whose diagnosis was done on the basis of clinical presentation and histopathology. Also immunohistochemistry was done.