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In Oman, many coastal sites dated to the Neolithic have yielded material culture related to ornament manufacture. These sites are the remnants of fishermen occupations, developing an economy mainly based on maritime and mangrove resources. The Omani islands of Maṣīrah and Al‐Ḥallāniyah are both situated in the Arabian Sea. Today, Maṣīrah is located about 20 km from the continent, while Al‐Ḥallāniyah is part of the Khurīyā Murīyā archipelago off the southern coast of Oman. On Maṣīrah, workshops have been discovered in Neolithic shell middens, revealing the work of stone and Spondylus sp. shells for bead production, using lithic tools. Separated by approximately 400 km from Maṣīrah, Al‐Ḥallāniyah yielded several Neolithic sites with similar evidence for shell bead production. The main lithic tools discovered are micro‐drills, pièces esquillées (splintered pieces) made of local chert, and multitasking tools made of stone, used as anvils, hammerstone and/or polishing stone. Most of the micro‐drills are made from bladelets either with sharped edges or with steep edges and testify to predetermined knapping operations. However, others created on undifferentiated flakes appear to be more opportunistic (or expedient). Micro‐drills of the Maṣīrah and Al‐Ḥallāniyah types seem to be quite new to the Neolithic toolkit of coastal Oman. Pièces esquillées demonstrate the use of bipolar flaking (performed on an anvil) but functional questions remain. These could be cores, but also chisels used between a hammer and a material (shell) placed on an anvil. Stone tools show marks that are characteristic of use as hammers, anvils and as tools used to polish the beads after perforation. [ABSTRACT FROM AUTHOR]

The machinic moving image has the power to engage with a larger audience than a drawing. It often strips away ambiguity, getting its message across fast and indelibly, coupled with the troubles of our age – particularly the mitigation of climate change, the need for profound international cooperation, and the sheer scale of the intervention required to ease these problems. Marissa Lindquist evokes Australian artist and filmmaker Liam Young's Great Endeavor film project that relishes a new technological sublime – long a preoccupation in his work. [ABSTRACT FROM AUTHOR]

Soil pollution by heavy metals (HMs) is a major environmental problem around the world. The addition of biowaste-based stabilizers for HM remediation has recently gained attention due to its relatively low cost and eco-risk, abundance, ease of operation, and quick remediation results. Among these stabilizers, shell (crustacean shell, bivalve shell, and eggshell), starfish, and bone-based stabilizers are particularly attractive because of their high Ca and P contents, allowing for highly efficient HM immobilization and simultaneous supplement of nutrients to the soil. However, a comprehensive review focusing on these stabilizers is currently missing. Therefore, this review attempts to summarize the HM immobilization efficiency of these stabilizers and the mechanisms associated with HM stabilization, and perform an operation cost estimation and cost comparison. Cost comparisons among different stabilizers are widely ignored in reviews due to the lack of reliable cost estimation tools or methods. However, for practical application in soil remediation, cost is one of the most important factors to consider. Thus, a simple but reasonable cost estimation method is developed and discussed in this review. Bivalve shell-based stabilizers demonstrated the most promising results for the immobilization of soil HMs in terms of higher performance and lower cost. Current research limitations, challenges, and recommendations regarding possible future research directions are also provided. [ABSTRACT FROM AUTHOR]

International Oil Companies (IOCs) are increasingly becoming key development actors in communities where they operate. This is becoming the norm as IOCs come to the realisation that their contributions to the well-being of their host communities brings them closer to attaining their business goals. The evaluation of Corporate Social Responsibility (CSR) actions by IOCs operating in Nigeria's oil rich Niger Delta is however characterised by a unilateral self-assessment by IOCs themselves, without commensurate integration of host community participation. In providing an alternative approach, this study utilised a participatory community-based appraisal to evaluate the Shell Petroleum Development Company's (SPDC), Global Memorandum of Understanding (GMoU) model within the praxis of selected parameters for sustainable community development including ownership, participation, sustainability and transparency. The study argues that due to the limitations of universal indicators in the assessment of community development problems, a combination of community-based parameters works better in evaluating community development. [ABSTRACT FROM AUTHOR]

The deep-sea raphitomid genus Gymnobela Verrill, 1884 (Neogastropoda: Conoidea) has historically been a container for a multitude of raphitomid species, assigned to this genus almost exclusively based on shell characters. Consequently, the genus has become taxonomically inflated. However, a 2021 molecular study redefined Gymnobela and taxonomically revised the genus. Herein, we present an integrative taxonomic study that, mainly based on samples from Australian waters, further defines this problematic genus, as well as the closely related genus Pontiothauma E.A. Smith, 1895. An automatic barcode gap discovery (ABGD) analysis of three mitochondrial genes resulted in six primary species hypotheses (four in Gymnobela and two in Pontiothauma). We recognised morpho-anatomical and bathymetric/geographical characters distinct to all six and found available names for four; we name one new species, Pontiothauma transregnasp. n., but abstain from naming one presumably unnamed Pontiothauma due to a lack of well-preserved adult specimen material. We provide clear synapomorphic characters unique to both Gymnobela and Pontiothauma, notably those of the radula. Furthermore, we present the first evidence supported by molecular data of a transoceanic distribution among the raphitomids, namely in Gymnobela angulosa Sysoev, 1988. Additionally, we recognise non-molecular evidence that might indicate similarly wide distributions in Gymnobela agasizzi (Verrill and Smith, 1880), Gymnobela engonia Verrill, 1884 and Gymnobela frielei Verrill, 1885. Consequently, and to avoid taxonomic splitting, we herein advocate for wide-ranging investigation of worldwide material when conducting taxonomic studies on deep-sea conoideans, due to growing evidence of transoceanic distributions in the group. Finally, through an exhaustive search of worldwide repositories and the literature, and in conjunction with our molecular, morpho-anatomical and bathymetric/geographical data, we have reassigned 16 species from Gymnobela to other genera within the family Raphitomidae. [ABSTRACT FROM AUTHOR]

Concrete shells, designed with near optimal shapes for uniform gravity loads, can be subjected to nonmembrane effects caused by nonuniform and asymmetrical loads. In this paper, a numerical study on the effect of normative loads on a thin triangular concrete shell with three supports is presented. Two actions were considered, wind and snow, which present high spatial variability in both intensity and direction, assuming the values established in Eurocode 1 for the worst possible location, in Portugal. Linear, nonlinear and stability analyses were performed using the ABAQUS software. Results suggest that the wind action, but especially the exceptional snow load in drifted arrangement, produce significant bending moments, leading to decompression, and eventually to the development of stresses above the tensile strength of current concrete classes. Therefore, the production of these shells by assembling prefabricated un‐reinforced modules, requires the use of ultrahigh‐performance fiber reinforced concrete, combined with prestressing. [ABSTRACT FROM AUTHOR]

Let a graph G = (V, E) be a (p, q) graph. Define ρ = {p/2, p is even p - 1/2, p is odd, and M = {±1, ±2, ⋯ ± ρ} called the set of labels. Consider a mapping λ : V → by assigning different labels in M to the different elements of V when p is even and different labels in M to p -- 1 elements of V and repeating a label for the remaining one vertex when p is odd. The labeling as defined above is said to be a pair mean cordial labeling if for each edge uv of G, there exists a labeling λ(2)+λ(v)/2 if λ(2) + λ(v) is even and λ(u)+λ(v)+1/2 if λ(u) + λ(v) is odd such that ... ≤ where ... and ... respectively denote the number of edges labeled with 1 and the number of edges not labeled with 1. A graph G with a pair mean cordial labeling is called a pair mean cordial graph. In this paper, we discuss here the pair mean cordial labeling of union graphs like Lm, υ Ln, Pm υ Ln, Cm Ln, Wm υ υ Ln, Sm υ Ln. [ABSTRACT FROM AUTHOR]

Snails exhibit remarkable adaptability, allowing them to flourish in diverse environmental conditions and resulting in thriving populations in specific regions. This abundance has led communities to harness snails for various purposes, including their use as animal feed, daily dietary source, and in traditional wound-healing practices with historical roots. The primary objective of this systematic review is to identify the snail species commonly employed in wound healing and evaluate the bioactivity of compounds derived from different snail species. This review was conducted using literature review method, drawing from international databases such as Scopus, and encompassed publications from 2013 to 2023. A total of 22 articles met the inclusion and exclusion criteria. Snail body parts that have been explored for wound-healing purposes include both the body and the shell, along with snail secretions, particularly their mucus. Various methods have been employed to extract mucus, involving manual stimulation of the snail's body, spraying with a saline solution (NaCl), application of electric shock, and the use of ozone gas through nebulisation. Prominent snail species found to be beneficial for wound healing include Achatina fulica, Helix aspersa, Eobania desertorum, Helix lucurus, Cornu bistrialis, Theba pisana, and Megalobulimus lopesi. These snail species demonstrate potential applications in the treatment of burns, excision wounds, incision wounds, and diabetic ulcers. Key compounds within snail secretions encompass mucopolysaccharides, polyphenols, peptides, and glycosaminoglycans. These compounds exert significant effects on haemostasis, inflammation control, cellular proliferation, and re-epithelialisation, significantly contributing to the wound healing process. [ABSTRACT FROM AUTHOR]

This article compares the results of estimating the buckling capacity of steel spherical shells using simple engineering formulas with the results of selected experimental studies that have been conducted over the past 70 years. It is worth noting that these studies were conducted by research centers from all over the world, and the tested coatings differed in material, manufacturing method, radius R, and thickness t. The test methods, procedures, and measurement tools were also different. The convergence of the results obtained between the proposed simple engineering approach, which is based on the provisions of EN-1993-1-6 and the recommendations in EDR5th, and the experimental studies is satisfactory, and in many cases the results obtained are almost identical. Therefore, it is possible to practically apply the developed algorithms for estimating the buckling capacity of steel spherical shells without worrying too much about the capacity reserve. [ABSTRACT FROM AUTHOR]

The problem of vibrations of plates and shells with a mass attached to the point was solved. A mathematical model was developed based on the hypothesis of nondeformable normals. The latter was used to derive a system of resolvable dynamic equations for the shell with a mass, where the unknowns are the dynamic deflection and stress function. The problem was solved numerically and analytically. In accordance with the boundary conditions, the shell deflection was expressed as double trigonometric series. The transition from the initial dynamic system to the solution of the final system of nonlinear ordinary differential equations was achieved by the Bubnov–Galerkin method. For time integration, the finite difference method was used.

The enormous diversity of molluscs has provided humans with food, colours, medicines and shells, among other resources. Molluscs have long been utilized in traditional medicine in several countries and they are a valuable source of medical supplies for many diverse communities worldwide. The purpose of this study was to identify and assess Cipangopaludina lecythis bioactive compounds in order to determine the nature of the primary ingredient that gives its medicinal properties. C. lecythis flesh and shell extracts using polar and lipophilic solvents were analyzed using liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). This study provides the first chemical assessment of flesh and shell-opercula of C. lecythis. Chemical analysis of flesh and shell-opercula of C. lecythis clearly showed the presence of major compounds such as chitin, allantoin, linoleic acid, dihydrotachysterol, cyclotrisiloxane hexamethyl and 6-gingerol besides other minor compounds with bioactive properties of medicinal significance. Overall, this research provides good evidence that C. lecythis produce secondary metabolites with a variety of intriguing pharmacological characteristics. They have also long been a part of traditional medicine in many human cultural groups. Its usage by traditional practitioners to treat a range of human diseases is justified by the presence of numerous medicinally significant bioactive chemicals. However, more research on the bioactive compounds found in snails is necessary to standardize the extraction techniques for their detection, quantification and formulations, to validate their in vivo efficacy, and confirm their safety.

The paper considers tasks related to the search for the parameters of smart-systems with piezoelectric elements, to the electroded surfaces to which elements of electrical circuits are connected. The required parameters should provide the maximum damping properties of the simulated systems at free and steady-state forced vibrations. The paper presents the results of calculations of smart-system parameters providing maximum damping properties at free and forced vibrations, which were performed in the framework of continuum and discrete mechanics models. The results demonstrate variants for which the parameters found based on continuum mechanics models provide higher vibration damping rates. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, the behavior of viscoelastic porous functionally graded (FG) shells regarding the free and damped forced vibration analysis is investigated. The differential equations are derived by using higher order shear deformation theory. Using Hamilton's principle and the energy method, the equations of motion are obtained and solved using Navier's method. The damping effect is implemented into the analysis by means of Kelvin and linear standard viscoelastic models. With the correspondence principle, the transition from elastic material properties to viscoelastic material properties is achieved. First, a free vibration analysis is performed to verify the accuracy of the developed algorithm and obtained results are compared with the existing studies in the literature. Afterwards, a parametric study considering two different viscoelasticity models is performed. In the first parametric example, damped forced vibration analysis is performed for simply supported FG cylindrical shell using linear standard viscoelastic model as the viscoelastic model. Then, damped forced analysis is performed using Kelvin viscoelastic model for simply supported FG cylindrical shell. Analyses are performed in Laplace domain. The obtained results are transferred to time domain using Durbin's inverse Laplace transform method. The displacement graphs are given for the damped forced vibration examples. In the performed parametric studies, the effects of various porosity coefficients, ratios of instantaneous value, retardation times of the relaxation function and damping ratios on the analysis are investigated. [ABSTRACT FROM AUTHOR]

1. A study was conducted to assess the possibility of totally replacing supplemental phosphorus sources in White Leghorn (WL) layer diets (aged 28 to 45 weeks of age) with microbial phytase supplementation. One thousand commercial layers (HyLine White) of 28 weeks of age were housed in California cages fitted in open-sided poultry shed at the rate of 20 layers in each replicate. Ten replicates were randomly allotted to each treatment, and the respective diet was fed from 28 to 45 weeks of age. 2. A control diet (CD) containing the recommended levels of non-phytate phosphorus (3.6 g/kg NPP) and four other test diets (2–5) having sub-optimal levels of NPP (2.4, 2.0, 1.6 and 1.2 g/kg), but with supplemental microbial phytase (600 FTU/kg) were prepared and fed for the trial duration. 3. The layers fed with lower levels of NPP with phytase had the same laying performance as the group fed the CD. Egg production, feed efficiency, egg mass, shell defects, egg density, shell weight, shell thickness, ash content and breaking strength of the tibia and sternum were not affected by feeding the lowest concentration of NPP (1.2 g/kg) plus microbial phytase. 4. Phytase supplementation in diets with sub-optimal levels of NPP (2.4, 2 and 1.6 g/kg) significantly improved the Haugh unit score compared to those fed the CD. 5. It was concluded that supplemental phosphorus can be completely replaced with microbial phytase (600 FTU/kg) in a diet without affecting egg production, shell quality or bone mineral variables in WL layers (28 to 45 weeks). [ABSTRACT FROM AUTHOR]

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the present paper is to investigate the influence of boundary conditions of rigid fastening on the boundaries of regions of dynamical instability of closed shells of revolution, close by their forms to cylindrical ones, with an elastic filler. It is assumed that a shell is under the action of external pressure which varies in time and temperature. We consider the shells of average length whose shape of generatrix of the middle surface is a parabolic function. We consider the shells of positive and negative Gaussian curvature. The formulas are obtained for finding eigenfrequencies and boundaries of regions of dynamical instability depending on the boundary conditions, Gaussian curvature, initial stressed state, temperature and amplitude of a shell deviation from cylindrical form. The focus is on finding the moot dangerous area of dynamical instability and on the lowest eigenfrequencies of shells under consideration. [ABSTRACT FROM AUTHOR]

The relationship between pangolin-CoV and SARS-CoV-2 has been a subject of debate. Further evidence of a special relationship between the two viruses can be found by the fact that all known COVID-19 viruses have an abnormally hard outer shell (low M disorder, i.e., low content of intrinsically disordered residues in the membrane (M) protein) that so far has been found in CoVs associated with burrowing animals, such as rabbits and pangolins, in which transmission involves virus remaining in buried feces for a long time. While a hard outer shell is necessary for viral survival, a harder inner shell could also help. For this reason, the N disorder range of pangolin-CoVs, not bat-CoVs, more closely matches that of SARS-CoV-2, especially when Omicron is included. The low N disorder (i.e., low content of intrinsically disordered residues in the nucleocapsid (N) protein), first observed in pangolin-CoV-2017 and later in Omicron, is associated with attenuation according to the Shell-Disorder Model. Our experimental study revealed that pangolin-CoV-2017 and SARS-CoV-2 Omicron (XBB.1.16 subvariant) show similar attenuations with respect to viral growth and plaque formation. Subtle differences have been observed that are consistent with disorder-centric computational analysis. [ABSTRACT FROM AUTHOR]

The sound localization behavior of the nocturnally hunting barn owl and its underlying neural computations is a textbook example of neuroethology. Differences in sound timing and level at the two ears are integrated in a series of well‐characterized steps, from brainstem to inferior colliculus (IC), resulting in a topographical neural representation of auditory space. It remains an important question of brain evolution: How is this specialized case derived from a more plesiomorphic pattern? The present study is the first to match physiology and anatomical subregions in the non‐owl avian IC. Single‐unit responses in the chicken IC were tested for selectivity to different frequencies and to the binaural difference cues. Their anatomical origin was reconstructed with the help of electrolytic lesions and immunohistochemical identification of different subregions of the IC, based on previous characterizations in owl and chicken. In contrast to barn owl, there was no distinct differentiation of responses in the different subregions. We found neural topographies for both binaural cues but no evidence for a coherent representation of auditory space. The results are consistent with previous work in pigeon IC and chicken higher‐order midbrain and suggest a plesiomorphic condition of multisensory integration in the midbrain that is dominated by lateral panoramic vision. [ABSTRACT FROM AUTHOR]

The main goal of this study is to use higher-order isogeometric analysis (IGA) to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials (FGM) skin layers (namely honeycomb-FGS shells) subjected to dynamic loading. Touratier's non-polynomial higher-order shear deformation theory (HSDT) is used due to its simplicity and performance. The governing equation is derived from Hamilton's principle. After verifying the present approach, the effect of input parameters on the dynamic response of honeycomb-FGS shells is carried out in detail. [ABSTRACT FROM AUTHOR]

Etheria elliptica is a freshwater oyster that produces an adhesive that hardens underwater, allowing them to attach to other oysters, rocks, wood, and other natural substrates, producing complex oyster bed communities. Despite the importance of the adhesive in oyster bed formation, little is known about its chemical composition, structure, or mechanical properties. Through a combination of scanning electron microscopy (SEM), x‐ray photoemission electron microscopy (X‐PEEM), infrared (IR) spectroscopy, microhardness testing, and nanoindentation, it is found that the oyster adhesive consists entirely of aragonite nanoparticles that clump together into crystallites of varied shape, size, and orientation. The crystallite clumping density varies from the exterior of the adhesive to the interior, with the adhesive closest to the prismatic layer generally being denser. With this variation in density comes a variation in material properties with the exterior adhesive layer being softer and more flexible and the interior adhesive layer being harder and less elastic, or more similar to the prismatic and nacre shell structures produced by the E. elliptica. The resultant material exhibits varied materials properties, despite similar mineral composition. [ABSTRACT FROM AUTHOR]

The structures of electrochemical membrane devices are analyzed. Formulas for calculating the volume and mass of the elements of the electric membrane device and the volume of the liquid being processed are obtained. A diagram of the device is presented. [ABSTRACT FROM AUTHOR]

The deep-sea clam Calyptogena marissinica is widely distributed in the Haima cold seep ecosystem on the northwestern slope of the South China Sea with low pH values, low temperature and high pressure. Limited information is available on the biomineralization of this species. In this research, we generated a comprehensive transcript dataset of C. marissinica's mantle tissue, and a total of 19821 unigenes were assembled. Fourteen shell matrix proteins (SMP)-related genes were identified. The qPCR results showed that four out of six prismatic matrix genes (MSP2, MSP5, prisilkin-39, and shematrin), four out of the six nacreous matrix genes (perlucin, pif, pif97, and papilin), and two extrapallial fluid proteins (SPARC and calmodulin) were significantly expressed in the mantle. Both the nacreous and the prismatic layers are chrysanthemum-shaped, which are stacked on the top of each other to form a laminated nacreous structure. The alignment and phylogenetic analysis of MSP-5, Prisilkin-39, Perlucin, and Pif homologues showed that some amino acids of C. marissinica that differed from those detected in other molluscs may cause the different shape of the nacreous and prismatic layers, but do not lead to a change in the species' evolutionary status. These results indicated the conservation of the functions of SMP-related genes in C. marissinica, and the specific shape of the prismatic and nacreous layers of this deep-sea mollusc, which will contribute to the research on the molecular regulation mechanisms of biomineralization in C. marissinica and provide a new perspective to investigate biomineralization in deep-sea clams in general. [ABSTRACT FROM AUTHOR]

For complex geometry shells, the approximate interaction model with piecewise continuous deformable bases located on the facial surfaces of the shell is considered. On the basis of equations obtained, a numerical technique for solution of statics and thermoelasticity tasks of shells of various classes, including shells of complex geometry, is developed on the base of combination of finite sums method and differential forms of finite element method. The use of the described model made it possible to analyze the strength of shell elements of aircraft structures with non-traditional methods of fastening. [ABSTRACT FROM AUTHOR]

The innovative integration of phase change materials (PCMs) into textiles through microencapsulation presents a transformative approach to developing thermally regulated fabrics. This study explores the synthesis and characterization of microcapsules containing a coconut oil core and an ethylcellulose shell, and their application on cotton fabrics coated with polyvinyl alcohol (PVA) nanofibers. The dual-layer system involving microcapsules and nanofibers is designed to enhance the thermal insulation properties of textiles by regulating heat through the absorption and release of thermal energy. The microencapsulation of PCMs allows for the effective incorporation of these materials into textiles without altering the fabric's inherent properties. In this study, the coconut oil serves as the PCM, known for its suitable phase change temperature range, while ethylcellulose provides a robust shell, enhancing the microcapsules' structural integrity. The application of a PVA nanofibers layer not only strengthens the thermal regulation properties but also protects the microcapsules from release while the fabric is manipulated, thereby prolonging the functional life of the fabric. Comprehensive testing, including scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), confirms the successful application and durability of the microcapsules on the textiles. Thermal imaging studies demonstrate the fabric's enhanced capability to maintain a consistent temperature, highlighting the potential of this technology in applications ranging from smart clothing to energy-efficient building materials or automotive isolation. The integration of PCMs in textiles via microencapsulation and nanofiber technology marks a significant advancement in textile engineering, offering new opportunities for the development of smart and sustainable materials. The study demonstrates the promising potential of integrating PCMs into textiles using microencapsulation and nanofiber technologies. Despite the initially modest insulation improvements, the methodology provides a robust foundation for further research and development. [ABSTRACT FROM AUTHOR]

This article provides a bibliographic and scientific overview of subspecies and forms in Albanian molluscs. Intraspecific diversity has to do with the levels of variation within species and is studied in individuals within the populations of a species or between populations. This article presents a profound overview of all existing published studies that we could find on the diversity in molluscs of Albania. The reviewed publications are presented in two groups: for subspecies with six published studies, as well as for forms, both in terms of polymorphism of individuals in population and population variation - with seven articles identified. The published knowledge of these phenomena is presented in every case in the form of a summary, extracted directly from the subject of the respective article, together with our own bibliographical indicia which facilitates researchers to use the correct published material that can be used from the reviewed studies. In the molluscs of Albania a high intraspecific diversity is ascertained, in terms of the diversity of subspecies and forms. Therefore, the reviewed publications can be used in terms of solving some problems of genetics, evolution, ecology, and zoogeography. [ABSTRACT FROM AUTHOR]

ABSTRACT Calcium is essential for bone development and eggshell formation in laying hen nutrition. It is therefore important to align the nutritional levels of calcium and the granulometry of limestone. The aim herein was to evaluate the effect of different calcium levels and two limestone granulometries on the performance, egg quality, digestive organ characteristics, and bone quality of layers in their second production cycle. A total of 324 Lohmann LSL Lite layers at 113 weeks of age were distributed in a completely randomized design with a 3 x 2 factorial scheme, with 3 calcium levels and 2 limestone granulometries, totalling 6 treatments with 6 replicates of 9 birds each. Performance, egg quality, digestive organ biometry, and bone characteristics were evaluated. The data were submitted to analysis of variance, and the means were compared by Tukey’s test. In addition, a canonical discriminant analysis (CDA) was carried out. There was no interaction between the factors for any of the variables. However, there was an effect of granulometry on egg weight, and of calcium levels on relative liver weight. No differences were observed in the CDA. It is concluded that coarse-grained limestone improves egg weight, and a 4.3% calcium level is recommended.

Background. The level of development of mechanical engineering significantly affects the economic potential and defense capability of the state. One of the main areas of mechanical engineering is the manufacture of products for aerospace technology. Thus, for the manufacture of liquid rocket engines, an important element is the nozzle part of the combustion chamber. It is a package of equidistant ogival shells, with increased requirements for the thickness variation of the resulting workpiece and deviation from the profile. The objective of the work is to produce competitively and economically viable products. Materials and methods. The most promising method for obtaining ogival shells is the method of rotational extrusion. Thus, to produce ogival thick-walled shells, Design bureau of chemical automation uses the KhTRV-2500 mill. Long-term operation and lack of modernization led to frequent failures in the control system and loss of accuracy and performance characteristics. Results. Thus, to increase the efficiency and reduce the energy intensity of the equipment, the electromechanical part of the mill was modernized by replacing the main two-motor thyristor direct current drive of the mandrel rotation with one asynchronous servomotor, while maintaining the sum of the motor torques. All feed servomotors have been replaced with asynchronous servomotors of lower power and torque. The element base has been completely updated and the outdated control system has been replaced. As a result of the modernization, the accuracy of the rolling rollers has been increased, as well as the speed of their approach and retraction, while ensuring an accurate change in the ratio of the feed speeds of the rollers and the rotation of the workpiece. Conclusions. The modernization of the unique specialized equipment allowed to ensure stable production of complex large-size ogival-shaped parts for special equipment products with increased accuracy and technological characteristics.

The aim of this review is to provide information concerning the types of chestnut shells (inner and outer), their compositions and bioactive compounds, as well as to mention industrial peeling applications. These shells are comprised of high-valued natural active compounds, such as polyphenols (phenolic acids, flavonoids, tannins, hydroxycoumarins -scopoletin, scoparone-), pigments (melanin) and minor compounds (minerals, dietary fiber, vitamin C and E, essential amino acids and fatty acids). The total phenolic acids and flavonoid content of C. sativa shell were ranged between 119.17-223.62 mg/kg db and 330 – 503 mg CE/g. It is also a good source of vitamin C with reported levels of 15.57 and 28.97 mg AA/100 mg db in water and ethanol extracts, respectively. The shells are used as food additives due to their colorant, antioxidant and antimicrobial properties. The shells are exposed by the peeling process applied to obtain the fruit without the shell which is mainly used. The most frequently used technique in chestnut peeling is the Brulage peeling method. However, in this technique, used peeling mechanism is insufficient to obtain both inner and outer shells separately at the same time. Moreover, further research is needed to obtain the shells individually, to analyse each shell in detail, and to increase the industrial use of shells.

• Successful restoration of two shell paintings from the Warring states period. • Identifying the mineral type of the pigment and obtaining its spectral information. • In-depth explanation of the picture details and discussion of its significance in early art history. The use of shells as a medium for painting is an exceptionally rare discovery in archaeology, representing a art form that has been largely overlooked. In this study, we present two shell paintings of the Warring States period (476–221 BCE) discovered in Zhongshan State, Hebei, China. Employing various techniques, including microscopic observation, computed tomography (CT), X-ray fluorescence (XRF), multispectral imaging, and Raman spectroscopy, we non-destructively unveil the exquisite images obscured by soil and reveal the unparalleled shallow relief technique employed in their creation. The identified pigments for the different paintings include cinnabar, charcoal black, and malachite. These elaborate depictions offer insights into the costume, rituals, life, hierarchy, and art of the Warring States period. The meticulous use of prominent lines emphasizes color patches rather than the brushstrokes relied upon in later stereotypical Chinese painting, significantly reshaping previous notions about the early development of Chinese painting. This unique expression undoubtedly refreshes our understanding of early ancient art. [ABSTRACT FROM AUTHOR]

The Sr/Ca and 87Sr/86Sr ratios are used as natural indicators (geomarkers) in fish to reveal migratory patterns, due to significant relationships between these ratios measured in the water and in the fish calcified structures (otoliths, bones). The aim of this study was to assess the potential use of the Limnoperna fortunei shell as a proxy for monitoring the spatial and temporal variability of Sr/Ca and 87Sr/86Sr in water. These ratios were compared in water samples and bivalve shells proceeding from eight sites of four hydrogeological regions of the La Plata Basin (Argentina and Uruguay), collected in two hydrological periods (winter and summer) in order to depict the pattern of geographical and temporal variability and to evaluate the relationship between both matrices. Significant positive linear relationships were found between shell edge and water for 87Sr/86Sr (R2 = 0.96–0.97, p < 0.005) and Sr/Ca (R2 = 0.83–0.86, p < 0.05) in summer and winter. Slopes did not differ significantly from 1 (p > 0.05) for 87Sr/86Sr, while they differed from 1 for Sr/Ca in both seasons (p < 0.05), indicating that the elemental ratio would be influenced by endogenous/exogenous factors. No significant seasonal differences were found for both natural tags (p > 0.05), except for the lower Uruguay River (87Sr/86Sr) and outer estuary (Sr/Ca). These results indicate that the L. fortunei shell could be a valuable tool for monitoring spatio-temporal variations in water 87Sr/86Sr. Shell Sr/Ca shows high potential utility as a geomarker in freshwater, but additional assessments are needed to understand the impact of temperature and growth on this ratio. [ABSTRACT FROM AUTHOR]

This paper presents a novel protective shell system designed to safeguard both the drone and its accompanying sensors. The objective of this project is to develop and test the shell-shaped container to check its capability of securely housing the drone. The system may incorporate a circuit board housing a processor that receives data from sensors and controls the opening and closing motions of the container. By analyzing the sensor information, the system may intelligently respond to adverse weather conditions by automatically closing the container to ensure the drone’s protection. This innovative solution addresses the challenges associated with deploying drones in outdoor environments and offers enhanced safety and durability for extended drone operations. [ABSTRACT FROM AUTHOR]

This paper presents comparative research on marine shell from four 19th century historical archaeological sites in Melbourne. The shell derives predominantly from Mud Oyster (Ostrea angasi) and Sydney Rock Oyster (Saccostrea glomerata) commercially harvested from natural reefs along the south‐east Australian coastline. The research collects quantitative data that informs on the 19th century oyster industry and investigates inter‐site shell variability and its implications for processing, consumption and discard. Dredging of subtidal reefs provides an explanation for the numerical dominance of oyster, the presence of subfossil cultch (Anadara) and the wide range of minor shellfish. Mud oyster and Sydney rock oyster comparisons in valve size, sided counts and preservation record significant differences within and between sites due to the origins, depositional conditions and the processing of the shell. These data form the basis of two models. The first predicts the archaeological representation of reef dredging and ranks shellfish according to categories, from live oysters to dead shell sampled from the reef substrate. Based on oyster shell anatomy and the separate uses of the right (lid) and left (dish) valves, the second model considers how oyster processing and consumption is characterised archaeologically in differential valve counts and pairing rates. [ABSTRACT FROM AUTHOR]

In this study, a new mixed-field zigzag shell model is proposed in terms of Reissner's Mixed Variational Theorem (RMVT) for the composite laminates with curvature. In this model, refined zigzag theory (RZT) is employed to improve the accuracy and efficiency by introducing through-the-thickness piecewise linear warping functions. Moreover, the shear correction factors are eliminated. It is also different from the published models for composite laminated shells, the continuity conditions of interlaminar transverse shear stresses (TSSs) are satisfied a priori based on RMVT. The equilibrium equations and related boundary conditions are also derived from RMVT. Subsequently, the static performance, natural frequencies, and critical loads of composite laminates with curvature are verified by comparing them with the 3D elastic solutions and other existing ones. It is observed that the present model accounts for not only the efficiency of the low-order models but also the accuracy of the high-order models. Finally, it is shown that the ply stacking, side-to-thickness ratios, and side-to-radius ratios play an important role in percentage errors between the present model and the previous ones. [ABSTRACT FROM AUTHOR]

In order to study the adsorption effect of peanut shell as adsorbent on dye wastewater in industry, the optimum adsorption conditions of peanut shell for methylene blue were explored in this article. The decolorized peanut shell was activated by zinc chloride and the adsorption rate of methylene blue dye was improved. Through the research of different conditions such as pH value, contact time, adsorption temperature, initial dye concentration and adsorbent dosage, the optimal adsorption conditions of methylene blue dye were obtained. The adsorption effect achieved was the best at pH 10. Kinetics, thermodynamics, adsorption isotherm properties of the adsorption of methylene blue onto the peanut shell activated by zinc chloride were studied. The adsorption satisfied the Freundlich isothermal adsorption equation and the adsorption process was exothermic. The present adsorption system is a heterogeneous adsorption. The adsorption of methylene blue onto peanut shell accorded with a quasi-second-order adsorption kinetics. This adsorption was a physicochemical adsorption. Finally, the involved adsorption materials prepared were characterized by scanning electron microscopy, X-ray diffraction and infrared spectroscopy. This method can effectively adsorb the methylene blue pollutants in water and solves the problem of the environmental pollution caused by the direct discharge of dye wastewater, which has certain economic and social benefits. [ABSTRACT FROM AUTHOR]

Features of shell and genitalia as well as nucleotide sequences of selected mitochondrial and nuclear genes of specimens of Monacha cantiana from ten northern French and two Dutch populations were compared with the same features of British and Italian populations. They were found to be very similar to populations previously identified as belonging to the CAN-1 lineage of M. cantiana. This confirms previous suggestions that M. cantiana was introduced to western Europe (England, France and the Netherlands) in historical times. [ABSTRACT FROM AUTHOR]

The mangrove oyster (Crassostrea) is one of the most common bivalves found on the Brazilian coast, widely used in artisanal fisheries. Oysters are dioecious with external reproduction, typically found in estuarine environments. The present study aimed to identify the population aspects of Crassostrea in different fishing locations in northeastern Brazil. The study area was the Acaú-Goiana Extractive Reserve, a protected area focused on the development of artisanal fisheries. Oysters were collected during low tide at three sampling points, where their removal from mangrove roots was carried out, during May, July, September, November 2021, and January and March 2022. In the laboratory, biometric measurements were conducted, and for the months of May and November 2021 histological preparations to study the reproductive cells. Biometric measurements were significantly higher in the dry season at all sampling points. The sex ratio was M = 0.38, F = 0.62, for May, and M = 0.30, F = 0.69, for November. The biometric and reproductive data obtained can support the development of management strategies, including a rotation plan between collection sites and the establishment of a minimum size for fishing. Here we recommend a minimum size of 20 mm shell length (SL) or larger for fishing. [ABSTRACT FROM AUTHOR]

The bending analysis of isotropic, laminated composite and cylindrical sandwich shells was carried out using a higher order shear deformation theory which incorporates undetermined integral in the displacement field. The model proposed involves only four variables. Moreover, unlike the conventional FSDTs, the shear correction factor is not necessary. The Hamilton's principle and the Navier's method are employed to determine and solve the equations of motion. The present analytical model was compared with other higher-order theories in the literature. In addition, finite element analysis methods were designed to calculate displacements and stresses of shells. Shells are subjected to uniform loads. Results are given for shallow and deep shells and thick to thin. According to the analysis, kinematics, based on the indeterminate integral component, are very effective and enable researchers to investigate laminated plates and shells more accurately than traditional models. [ABSTRACT FROM AUTHOR]

A hexagonal marble object from the Rockefeller Museum, Jerusalem, found during excavations of H. D. Colt in the 1930s, has been identified as a canopy of an ambo. It probably belonged to one of the churches in Byzantine Shivta and is published here for the first time. Dated most likely to the 6th–early 7th century, it constitutes rare evidence of this liturgical furnishing in the Negev, raising questions concerning its unique iconography and acoustic applications. [ABSTRACT FROM AUTHOR]

Blue‐emitting perovskite nanocrystals (NCs) are important components of high‐definition display device, but their instability to light and moisture severely hinders the commercial application. Here, a dual‐site passivation strategy is proposed and the halogen–halogen bond to surface capping molecules is applied. The bi‐functional molecule with a fluorine group and carboxyl group on the phenyl ring, would form a shell‐like molecular structure covering the nanocrystal surface at halogen and lead site via halogen‐halogen bond and coordination effect, respectively. Considering the binding strength and acid dissociation constant of several fluoro acids, the optimal optical properties and film stability confirm the para‐fluorobenzoic acid molecule provides the most effective protection for initial perovskite products account for their stronger anchoring affinity and more comprehensive surface coverage. Consequently, this work sheds light on the molecular functionality and configuration are crucial for surface properties of perovskite NCs. [ABSTRACT FROM AUTHOR]