The eggshell is a composite and highly ordered structure formed by biomineralization. Besides other functions, it has a vital and intricate role in the protection of an embryo from various potentially harsh environmental conditions. Solid-state nuclear magnetic resonance (SSNMR) has been used for detailed structural investigations of the chicken, tinamou, and flamingo eggshell materials. 31P NMR spectra reveal that hydroxyapatite and β-tricalcium phosphate in the ratio 3:2 represent major constituents of phosphate species in the eggshells. All three eggshells exhibit similar spectra, except for the line widths, which implies different structural order of phosphate species in the chicken, tinamou, and flamingo eggshells. 1H NMR spectra for these materials are comparable, differentiating overlapped peaks in three spectral regions at around 7, 4-5, and 1-2 ppm. These spectral regions have been attributed to protons from NH or CaHCO3, water, and possibly isolated monomeric water molecules or hydroxyl groups in calcium-deficient hydroxyapatite. 1H-13C CP MAS NMR revealed the presence of organic matter in the form of lipids and proteins. Two overlapped resonances in the carbonyl region at around 173 and 169 ppm are assigned to the carbonyls of the peptide bonds and the bicarbonate unit in calcite, respectively. Fourier-transform infrared spectroscopy (FTIR) spectra confirmed the presence of structural units detected in the NMR spectra.

Avian eggshells exhibit excellent antimicrobial properties. In this study, we conducted simulation experiments to explore the defense mechanisms of eggshell membranes with regards to their physical features. We developed a mathematical model for the movement of microorganisms and estimated their penetration ratio into eggshell membranes based on several factors, including membrane thickness, microbial size, directional drift, and attachment probability to membrane fibers. These results not only suggest that an eggshell membrane with multiple layers and low porosity indicates high antimicrobial performance, but also imply that the fibrous network structure of the membrane might contribute to effective defense. Our simulation results aligned with experimental findings, specifically in measuring the penetration time of Escherichia coli through the eggshell membrane. We briefly discuss the significance and limitations of this pilot study, as well as the potential for these results, to serve as a foundation for the development of antimicrobial materials.

The objective of this study was to evaluate the synergistic effect of eggshell-derived nanohydroxyapatite (EnHA) and carboxymethyl chitosan (CMC) in remineralizing artificially induced dentinal lesions. EnHA and CMC were synthesized using simple chemical processes and characterized using FTIR, XRD, HRSEM-EDX, TEM, DLS and TGA/DTA analyses. A total of 64 pre-demineralized coronal dentin specimens were randomly subjected to following treatments (n = 16):artificial saliva (AS), EnHA, CMC, and EnHA-CMC, followed by pH cycling for 7 days. HRSEM-EDX, Vickers-indenter, and micro-Raman analyses were used to assess surface-topography, microhardness, and chemical analysis, respectively. All tested materials demonstrated non-cytotoxicity when assessed on hDPSCs using MTT assay. FTIR, XRD and thermal analyses confirmed the characteristics of both EnHA and CMC. EnHA showed irregular rod-shaped nanoparticles (30-70 nm) with the presence of Ca,P,Na, and Mg ions. Dentin treated with EnHA-CMC exhibited complete tubular occlusion and highest microhardness whereas the AS group revealed the least mineral deposits (p < 0.05). No significant differences were observed between EnHA and CMC groups (p > 0.05). In addition, molecular conformation analysis revealed peak intensities in collagen\'s polypeptide chains in dentin treated with CMC and EnHA-CMC, whereas other groups showed poor collagen stability. The results highlighted that EnHA-CMC aided in rapid and effective biomineralization, suggesting its potential as a therapeutic solution for treating dentin caries.

OBJECTIVE: The purpose of the present in vitro study is to investigate and compare the remineralising potential of Moringa Oleifera extract, eggshell, and sodium fluoride varnish on microhardness of artificially demineralised enamel of primary teeth with biomimetic minimally invasive approach following the world paradigm shift towards natural products in paediatric dentistry.
METHODS: Sample size included 44 primary molars. The mineral content and surface microhardness of all specimens were initially assessed using energy dispersive x-ray examination (EDX) and Vickers microhardness. The specimens were artificially demineralised for 96 h at a temperature of 37°C and then reassessed directly after demineralisation. The demineralised enamel specimens were randomly divided into four groups according to the remineralisation regimen utilised. Group 1: Artificial saliva (control); Group 2: Sodium fluoride varnish; Group 3: Eggshell hydrogel; and Group 4: Moringa Oleifera hydrogel. The specimens were stored for 8 days and then subsequently evaluated using EDX and microhardness assessment by Vickers microhardness test and scanning electron microscope (SEM).  Results: Regarding the microhardness test, there was a significant difference between the Moringa Oleifera group and Eggshell group compared to fluoride varnish (p < 0.05). Regarding EDX analysis, there was a statistically significant difference (p < 0.05) between Moringa Oleifera group and Eggshell group compared to fluoride varnish as the highest values were for Moringa Oleifera and Eggshell. On the other hand, there was no statistically significant difference (p > 0.05) between Moringa Oleifera and Eggshell in both the measurements.
CONCLUSIONS: Moringa Oleifera and Eggshell might be considered as a biomimetic natural material capable of guiding enamel tissue remineralisation in early carious lesion of primary teeth.
CONCLUSIONS: This research demonstrated the capability for early enamel caries to be remineralised using novel materials with a naturally counterpart implicated in biomineralisation as proved to be more effective than traditionally used fluoride varnish in primary teeth.

Calcium and vitamin D deficiencies have been ongoing problems in Koreans due to a lack of food sources of calcium and vitamin D. Postmenopausal women aged 50 to 64 years (n = 25) were randomly assigned to consume three home meal replacements (HMRs)/week with (treatment) and without (control) eggshell powder and vitamin D for 6 months. Additionally, subjects who agreed to continue the study consumed the same three HMRs/week for an additional 6 months in this randomized double-blind study. We confirmed the high compliance of the study participants by analyzing carotenoids, the bioactive substances of HMRs, in the blood. The treatment group consumed an additional 261 mg/d of calcium and 10.3 μg/d of vitamin D from the HMRs, thus meeting the recommended intakes of calcium and vitamin D for Koreans. As a result of consuming fortified HMRs for 6 months, the decline in femoral neck bone density was significantly reduced in the treatment group (p = 0.035). This study indicates that inexpensive eggshell powder may be a good source of calcium for populations with low consumption of milk and dairy products. Additionally, functional HMRs fortified with eggshell powder and vitamin D can be a good dietary strategy for bone health.

The current research intended to examine the impact of dietary lemon peel powder (LPP) on laying quail performance, egg quality criteria, and the antioxidant capacity of the yolk. A total of 120 female Japanese quails (272.6±9.3 g), aged 21 weeks, were allotted to 6 trial groups, each with 5 replicates of 4 quails. Additions of 0, 1, 2, 3, 4, or 5 g/kg of LPP to the basal diet were used to create the treatment groups. Quails were fed ad libitum for 70 days. Neither performance parameters nor egg production was affected by LPP. However, eggshell-breaking strength improved by adding 2 g/kg LPP to the diet, but worsened at 5 g/kg. Moreover, the relative weight of eggshell and yolk L* value decreased with the treatments. Dietary LPP enhanced oxidative stability, reducing malondialdehyde (MDA) and increasing 1,1-diphenyl-2-picrylhydrazyl (DPPH) yolk values. The current study demonstrated that LPP, a safe and easily accessible agricultural by-product, enhanced eggshell quality when it was included in the diet of laying quails at doses of 2 g/kg. In contrast, improvement of yolk antioxidant capacity required increased amounts of LPP (4 g/kg). LPP could be advantageous to animal nutrition as an adequate substitute to reduce waste by-products.

The excessive discharge of phosphorus from rural domestic sewage is a problem that worthy of attention. If the phosphorus in the sewage were recovered, addressing this issue could significantly contribute to mitigating the global phosphorus crisis. In this study, corn straw, a common agricultural waste, was co-pyrolytically modified with eggshells, a type of food waste from university cafeterias. The resulting product, referred to as corn straw eggshell biochar (EGBC) was characterized using SEM, XRD, XPS, XRF, and other methods. Batch adsorption experiments were conducted to determine the optimal preparation conditions of EGBC and to explore its adsorption characteristics. EGBC showed strong adsorption effectiveness within a pH range of 5-12. The adsorption isotherm closely followed the Sips model (R2  > 0.9011), and the adsorption kinetics were more consistent with the pseudo-second-order model (R2  > 0.9899). The process was found to be both spontaneous and endothermic. Under optimal conditions, the phosphorus adsorption capacity of EGBC was measured to be 288.83 mg/g. This demonstrates the high efficiency of EGBC for phosphorus removal and illustrates an effective method of utilizing food waste for environmental remediation. PRACTITIONER POINTS: Biochar prepared from waste eggshell was used to removal and recovery phosphorus in wastewater treatment. EGBC has an impressive adsorption capacity that can reach up to 288.83 mg/g. EGBC has excellent adsorption and filtration capabilities, and there is a sudden increase in concentration at 900 min in the breakthrough curve of EGBC. EGBC has good regeneration performance, with an adsorption effect of 65% and an adsorption capacity of 121 mg/g after four desorption and regeneration cycles.

BACKGROUND: Eggshell speckle phenotype is an important trait in poultry production because they affect eggshell quality. However, the genetic architecture of speckled eggshells remains unclear. In this study, we determined the heritability of eggshell speckles and conducted a genome-wide association study (GWAS) on purebred Rhode Island Red (RIR) hens at 28 weeks to detect potential genomic loci and candidate genes associated with eggshell speckles.
RESULTS: The heritability of eggshell speckles was 0.35 at 28 weeks, and the speckle level is not related to other eggshell quality traits in terms of phenotypic correlation. We detected 311 SNPs (6 significantly, and 305 suggestively associated) and 39 candidate genes associated with eggshell speckles. Based on the pathway analysis, the 39 candidate genes were mainly involved in alpha-linolenic acid metabolism, linoleic acid metabolism, ether lipid metabolism, GnRH signaling pathway, vascular smooth muscle contraction, and MAPK signaling pathway. Ultimately, ten genes, LOC423226, SPTBN5, EHD4, LOC77155, TYRO3, ITPKA, DLL4, PLA2G4B, PLA2G4EL5, and PLA2G4EL6 were considered the most promising genes associated with eggshell speckles that were implicated in immunoregulation, calcium transport, and phospholipid metabolism, while its function in laying hens requires further studies.
CONCLUSIONS: This study provides new insights into understanding the genetic basis of eggshell speckles and has practical application value for the genetic improvement of eggshell quality.

Microaggressions targeting clinical learners cause harm and threaten learning. Clinical supervisors can be powerful allies by intervening when microaggressions occur. This study explored general and student-nominated skilled supervisors\' perspectives on responding to microaggressions targeting clinical learners.
This single-institution, qualitative study within a constructivist paradigm explored faculty supervisor experiences with bystander response to microaggressions targeting learners. Clinical supervisors in medicine and surgery departments and those across departments nominated by students as skilled microaggression responders were invited to discuss microaggression scenarios targeting students in semistructured focus groups in the U.S. in 2020-2021. Investigators applied the framework method of thematic analysis to identify themes.
Forty-two faculty (31 medicine and surgery [\"general\"], 11 \"student-nominated\" as skilled responders) joined 10 focus groups (6 \"general,\" 3 \"student-nominated,\" 1 mixed). Four themes characterized experiences responding to microaggressions targeting learners: bystander goals, noticing, acting, and continuous learning. Participants\' response goals were protecting learners, safeguarding learning, and teaching microaggression response skills. Noticing was influenced by past experiences with microaggressions and acculturation to clinical environments. Bystander action stemmed from (1) microaggression type, (2) personal emotional vulnerability, (3) knowledge of student preferences for supervisor response, and (4) clinical and educational context. Bystander action was more common when participants regarded all microaggressions as harmful, understood student preferences for faculty response, expected to err (growth mindset), and framed microaggressions as opportunities for humble reflection, intellectual candor, and teaching. Microaggression response required continuous learning through informal and formal skills development.
Complex factors govern faculty bystander response to microaggressions targeting clinical learners. Efforts to strengthen faculty bystander response should incorporate skill-building around preemptive discussions with learners and using intellectual candor to promote psychological safety, learning, and bystander action. Additional investigation is needed on how to incorporate these skills into team workflows and to assess outcomes of specific response strategies.

This study aimed to assess the calcium (Ca2+) and hydroxyl (OH-) ion-releasing ability, namely the biointeractivity of eggshell-derived hydroxyapatite (ESDHA) in comparison with mineral trioxide aggregate (MTA) and calcium hydroxide (CH). ESDHA, MTA and CH samples (n = 10; 8 × 1.6 mm) were immersed in 10 mL of deionised water (37°C, pH 6.8). Ca2+ and OH- ion releases were detected in 1, 7 and 21 days. Scanning electron microscopy and Fourier transform infrared spectroscopy analyses were also conducted. IBM SPSS 20.0 was used for statistical analyses. The cumulative Ca2+ ions (56.22 ± 11.28 ppm) were detected as most significant in ESDHA (day 21; p < 0.05). The OH- ion values of the ESDHA group were statistically higher than MTA and CH (days 1 and 7; p < 0.05). ESDHA and CH showed a similar pattern with sharp peaks in Ca2+, oxygen and carbon elements. ESDHA being a sustainable material with a high ion-releasing ability may be a preferable alternative to the commercial vital pulp therapy agents.