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For past societies on the Iberian Peninsula, one of the most prolific architectures was earthen construction, with a wealth of typologies and solutions derived from the legacy of local construction and materials. However, its study within the field of archaeology has been limited. The challenges posed by conservation, archaeological identification and social recognition have traditionally limited the dissemination of this type of architecture. Its low profile is perceived as fragile once the original protections collapse. The ethnological information preserved and linked to past ways of life and societies is crucial to the interpretation of the cultural development handed down over generations by different communities and now transmitted to the general public through archaeological sites. This research aims to provide an overview of the main earthen vestiges from domestic, productive and funerary architecture dating from the prehistoric, protohistoric, Roman and medieval periods. For this, a bibliographical review and data collection through fieldwork were conducted for numerous case studies. These included the classification of materials, compositions and construction techniques, creating an integrated comprehensive database with information on geography, measurements and the general state of conservation. [ABSTRACT FROM AUTHOR]

This paper delves into the investigation and inventory of cob buildings within the Guérande Peninsula, employing an interdisciplinary framework merging academic inquiry, fieldwork, and digital cartographic methodologies. Against the backdrop of escalating environmental concerns within the construction sector, raw earth construction emerges as a compelling avenue for sustainable building practices due to its low embodied energy and reversible characteristics. Despite historical prevalence in regions such as northwest France, traditional earth-building techniques have experienced waning prominence with the advent of industrial materials. However, the resurgence of interest in raw earth's minimal carbon footprint has catalyzed renewed attention towards earth-building methods. Through a meticulous investigation methodology, this study identifies and analyzes 802 potentially old cob buildings, with 46 structures confirmed as cob constructions. Employing statistical analyses of building characteristics, including wall and lift heights, preservation states, and geographical distributions, this research sheds light on the significance of preserving cob heritage amidst rapid urbanization. The findings underscore the imperative for ongoing research and awareness efforts to safeguard these vernacular architectural traditions. By illuminating centuries-old building practices, this research contributes to the scholarly discourse on sustainable construction methodologies and local cultural preservation. Moreover, it underscores the necessity of integrating traditional knowledge systems with contemporary sustainability initiatives to foster resilience and longevity within the built environment. [ABSTRACT FROM AUTHOR]

For past societies on the Iberian Peninsula, one of the most prolific architectures was earthen construction, with a wealth of typologies and solutions derived from the legacy of local construction and materials. However, its study within the field of archaeology has been limited. The challenges posed by conservation, archaeological identification and social recognition have traditionally limited the dissemination of this type of architecture. Its low profile is perceived as fragile once the original protections collapse. The ethnological information preserved and linked to past ways of life and societies is crucial to the interpretation of the cultural development handed down over generations by different communities and now transmitted to the general public through archaeological sites. This research aims to provide an overview of the main earthen vestiges from domestic, productive and funerary architecture dating from the prehistoric, protohistoric, Roman and medieval periods. For this, a bibliographical review and data collection through fieldwork were conducted for numerous case studies. These included the classification of materials, compositions and construction techniques, creating an integrated comprehensive database with information on geography, measurements and the general state of conservation.

This paper delves into the investigation and inventory of cob buildings within the Guérande Peninsula, employing an interdisciplinary framework merging academic inquiry, fieldwork, and digital cartographic methodologies. Against the backdrop of escalating environmental concerns within the construction sector, raw earth construction emerges as a compelling avenue for sustainable building practices due to its low embodied energy and reversible characteristics. Despite historical prevalence in regions such as northwest France, traditional earth-building techniques have experienced waning prominence with the advent of industrial materials. However, the resurgence of interest in raw earth’s minimal carbon footprint has catalyzed renewed attention towards earth-building methods. Through a meticulous investigation methodology, this study identifies and analyzes 802 potentially old cob buildings, with 46 structures confirmed as cob constructions. Employing statistical analyses of building characteristics, including wall and lift heights, preservation states, and geographical distributions, this research sheds light on the significance of preserving cob heritage amidst rapid urbanization. The findings underscore the imperative for ongoing research and awareness efforts to safeguard these vernacular architectural traditions. By illuminating centuries-old building practices, this research contributes to the scholarly discourse on sustainable construction methodologies and local cultural preservation. Moreover, it underscores the necessity of integrating traditional knowledge systems with contemporary sustainability initiatives to foster resilience and longevity within the built environment.

This paper describes a novel methodology for establishing the relative moisture performance of renders used to protect a novel walling system combining traditional dense cob with a low-density thermal cob. A new method of enhancing the thermal insulation of cob walls has been developed by an European Union (EU)-funded joint UK and French project called CobBauge. The external surface of traditional cob walls (comprising subsoil, fibre and water) is normally protected from driving rain by placing the walls on a short wall called a plinth, a pronounced eaves overhang and a breathable exterior render. As the low-density fibre and clay insulating layer in the CobBauge system differs from traditional cob, a method of establishing the moisture-related performance of a range of renders needed to be instituted to aid the materials selection process. A series of test panels were constructed with the thermal cob infill, faced by a number of render types. The panels were hung in an open position in a high exposure zone and the moisture content monitored using wood-block sensors, electrical resistivity and gravimetric measurements over a period of six months. The wood-block and electrical resistivity moisture measurements showed a good level of agreement with gravimetric measurements and showed a clear differentiation between the various render choices. [ABSTRACT FROM AUTHOR]

In recent years, there has been great interest in sustainable construction, which has led to an increased interest in 3D printing or additive manufacturing. However, the use of this technique with conventional materials is not enough to reduce the large environmental impact generated by the construction sector. Although most of the research and advances are focused on the 3D printing of Portland concrete, this review has been oriented towards the 3D printing of building materials based on soils and clays, which can provide an affordable (as it is a locally available material in many regions of the planet), environmentally sustainable, and low-cost approach, which is highly beneficial for housing construction. This paper has been oriented towards the search of scientific literature and prototypes that have been elaborated using ancestral materials, such as soil-clay-sand-sand-fibers like straw and water, for the elaboration of constructive pieces such as 3D printed walls or adobes. The objective of this paper is to close the gap on the use of mixtures based on soils, which, although they seem to have been fully studied for several centuries, to date their application in 3D printing is reduced. Readjustments in properties of soil mixtures such as fluidity for pumping or extrusion, buildability and good working time are variables that are reported in this paper. In addition, this review describes the mixtures that have been developed for 3D printing from soils and clays, and the main characteristics that have been found. Finally, the challenges that still remain for the blends to be applied on a massive industrial scale are presented. [ABSTRACT FROM AUTHOR]

This study examined the shrinkage rate and mechanical properties of cob samples. Cob is a natural building material composed of clay, water, and varying amounts of plant fibres. The red and beige cob materials in this study containing 3% and 6% wheat fibres were manufactured by hand with clay, bulk fibres (short and long fibres), and a 25% water ratio (water/clay) in order to make their manufacture and use on construction sites feasible and simple. The reference samples were mixed with clay, 25% water, and 0% wheat fibre. The mechanical properties were assessed through compression and flexural tests after 28 and 120 days. The results showed that the fibre addition decreased the bulk density of the composites from 1902 kg/m3 to 1264 kg/m3. The compressive strength increased from 1.8 MPa to 4.57 MPa for the red clay samples and from 1.65 MPa to 4.61 MPa for the beige clay samples at 28 days. The compressive strength of each mixture decreased slightly with age for the red and beige clay samples, respectively. Conversely, the flexural strength increased with age for the samples reinforced with 3% and 6% fibres. The results also showed that the cob samples can deform without breaking. Increasing the fibre content in the mix resulted in a significant reduction in the shrinkage rate and an increase in the mass loss rate during thermogravimetric analysis. This analysis showed a total mass loss of approximately 5.64%, 6.12%, and 44.87% for the red clay, beige clay, and fibres, respectively. An average volume shrinkage of 1% was observed for the samples with 6% fibre content. The cob discussed in this article can be used as a filling material. In large quantities, it can be made by hand, with feet protected by boots, or with the use of a mixer. The environmental benefits are considerable, as the raw materials are renewable, and the manufacturing process is less energy-intensive. [ABSTRACT FROM AUTHOR]

En los últimos años, se ha generado gran interés en la construcción sostenible, lo que ha llevado a un mayor interés en la impresión 3D o manufactura aditiva. Sin embargo, el uso de esta técnica con materiales convencionales no es suficiente para disminuir el gran impacto ambiental que genera el sector de la construcción. Aunque la mayoría de las investigaciones y avances están centralizadas en la impresión 3D de concreto Portland, esta revisión se ha trabajado orientada hacia la impresión 3D de materiales de construcción basados en suelos y arcillas, los con los cuales se puede proporcionar un enfoque asequible (ya que es un material localmente disponible en muchas regiones del planeta), sostenible ambientalmente, y con bajo costo, lo cual es altamente beneficioso para la construcción de viviendas. Este documento se ha orientado hacia la búsqueda de literatura científica y prototipos que se han elaborado utilizando materiales ancestrales, como son suelos-arcillas-arena-fibras como paja y agua, para elaboración de piezas constructivas tipo muros o adobes impresos en 3D. El objetivo de este documento es cerrar la brecha sobre la utilización de mezclas basadas en suelos, que, aunque parezcan totalmente estudiadas por varios siglos, a la fecha su aplicación en impresión 3D es reducida. Reajustes en propiedades de las mezclas de suelos como la fluidez para el bombeo o extrusión, edificabilidad y buen tiempo de trabajo, son variables que se reportan en este documento. Además, en esta revisión se describen las mezclas que han sido desarrolladas para impresión 3D a partir de suelos y arcillas, y las principales características que se han encontrado. Finalmente, se presentan los desafíos que aún persisten para que las mezclas puedan aplicarse a una escala industrial masiva.

In this paper, Mn 0.5 Cd 0.5 S (MCS) was prepared by hydrothermal method and CoB was introduced as a co-catalyst for the synthesis of CoB/Mn 0.5 Cd 0.5 S (CBMCS). After the characterization of UV–vis DRS, PL, photocurrent, EIS, LSV and Mott-Schottky, it is proved that the introduction of CoB plays a prominent role in inhibiting the photogenerated charge recombination and boosting the responsiveness to visible light. The photocatalytic hydrogen precipitation experiments revealed that the hydrogen evolution rate of CBMCS composite was up to 3810.0 μmol h−1 g−1, which was 7.0 times higher than MCS with a hydrogen precipitation rate of 543.3 μmol h−1 g−1, and 2.2 times higher than 1%Pt/MCS with a hydrogen evolution rate of 1729.1 μmol h−1 g−1 and kept excellent stability. Then by theoretical calculation and UPS, the work function was obtained to prove the formation of the Schottky junction between MCS and CoB. Obviously, this study provides a low-cost and effective co-catalyst to replace the precious metal Pt, offering a doable scheme to boost the photocatalytic activity of Mn 0.5 Cd 0.5 S. [Display omitted] • CoB/Mn 0.5 Cd 0.5 S (CBMCS) photocatalyst with schottky junction was successfully prepared. • CBMCS photocatalyst exhibits excellent performance for splitting water to H 2. • An inexpensive and effective cocatalyst replaced Pt was shown. • The possible mechanism of CBMCS photocatalytic materials is proposed. [ABSTRACT FROM AUTHOR]

The population of developed nations spends a significant amount of time indoors, and the implications of poor indoor air quality (IAQ) on human health are substantial. Many premature deaths attributed to exposure to indoor air pollutants result from diseases exacerbated by poor indoor air. CO2, one of these pollutants, is the most prevalent and often serves as an indicator of IAQ. Indoor CO2 concentrations can be significantly higher than outdoor levels due to human respiration and activity. The primary objective of this research was to numerically investigate the indoor relative humidity and CO2 in cob buildings through the CobBauge prototype, particularly during the first months following the building delivery. Both in situ experimental studies and numerical predictions using an artificial neural network were conducted for this purpose. The study presented the use of a piecewise autoregressive exogenous model (PWARX) for indoor relative humidity (RH) and CO2 content in a building constructed with a double walling system consisting of cob and light earth. The model was validated using experimental data collected over a 27-day period, during which indoor RH and CO2 levels were measured alongside external conditions. The results indicate that the PWARX model accurately predicted RH levels and categorized them into distinct states based on moisture content within materials and external conditions. However, while the model accurately predicted indoor CO2 levels, it faced challenges in finely classifying them due to the complex interplay of factors influencing CO2 levels in indoor environments. [ABSTRACT FROM AUTHOR]

The application of nitrogen-fixing microorganisms has shown benefits in plant nutrition. This research aimed to evaluate the effect of the application of nitrogen-fixing microorganisms on the growth of corn (Zea mays L.) crops. The experiment used a randomized complete block design (RCDB), with three repetitions. The treatments applied were: T1 - Paenibacillus polymyxa 2 L ha-1; T2 - P. polymyxa 3 L ha-1; T3 - P. polymyxa 4 L ha-1; T4 - Azotobacter chroococcum 2 L ha-1; T5 - A. chroococcum 3 L ha-1; T6 - A. chroococcum 4 L ha-1; T7 - P. polymyxa + A. chroococcum 2 L ha-1; T8 - P. polymyxa + A. chroococcum 3 L ha-1; T9 - P. polymyxa + A. chroococcum 4 L ha-1 y T10 - Control (without application). The variables evaluated were: plant height, stem diameter and insertion of the cob. The results showed that at 55 days after sowing (DDS) of the crop, good growth was obtained in the corn plants with a height of 182.01 cm and stem diameter of 20.14 mm with the application of the T9 - P. polymyxa + A. chroococcum. In addition, the insertion of the cob was also at 120 cm in height, for this same treatment. [ABSTRACT FROM AUTHOR]

An experiment was conducted to investigate the effects of different doses and application methods of urea-phosphate on the growth, yield, and nutrient use efficiency of maize. The experiment included four urea-phosphate application methods: control (no urea-phosphate) (T1), 50% of the recommended rate (T2), 75% of the recommended rate (T3), and the recommended rate (T4). The application methods comprised soil application (A1), soil application with fertigation (A2) and foliar application (A3). The experiment followed a completely randomized design with three replications. Various growth attributes, yield parameters, and nutrient use efficiency were measured, including plant height, number of leaves per plant, cob length, number of grain lines per cob, number of grains per cob, biological yield, grain yield, 1000 grain weight, harvest index, Photosynthetic rate, Transpiration rate, Sub-stomatal CO2 growth rate. Quality parameters like starch and protein were also measured. The collected data were subjected to statistical analysis using the Tukey test followed by analysis of variance technique. Soil application and fertigation generally yielded better outcomes compared to foliar application. Fertigation resulted in the highest average plant height, number of leaves per plant, cob length number of grain lines per cob and grain yield. Overall, the application methods and doses of ureaphosphate had a significant influence on maize growth, yield, and nutrient use efficiency. Soil application and fertigation methods were found to be more effective than foliar application. The study suggested that urea-phosphate, particularly when applied at the recommended rate through soil or fertigation, can enhance maize growth and yield. [ABSTRACT FROM AUTHOR]

Boron presents an important role in chemistry, biology, and materials science. Diatomic transition-metal borides (MBs) are the building blocks of many complexes and materials, and they present unique electronic structures with interesting and peculiar properties and a variety of bonding schemes which are analyzed here. In the first part of this paper, we present a review on the available experimental and theoretical studies on the first-row-transition-metal borides, i.e., ScB, TiB, VB, CrB, MnB, FeB, CoB, NiB, CuB, and ZnB; the second-row-transition-metal borides, i.e., YB, ZrB, NbB, MoB, TcB, RuB, RhB, PdB, AgB, and CdB; and the third-row-transition-metal borides, i.e., LaB, HfB, TaB, WB, ReB, OsB, IrB, PtB, AuB, and HgB. Consequently, in the second part, the second- and third-row MBs are studied via DFT calculations using the B3LYP, TPSSh, and MN15 functionals and, in some cases, via multi-reference methods, MRCISD+Q, in conjunction with the aug-cc-pVQZ-PPM/aug-cc-pVQZB basis sets. Specifically, bond distances, dissociation energies, frequencies, dipole moments, and natural NPA charges are reported. Comparisons between MB molecules along the three rows are presented, and their differences and similarities are analyzed. The bonding of the diatomic borides is also described; it is found that, apart from RhB(X1Σ+), which was just recently found to form quadruple bonds, RuB(X2Δ) and TcB(X3Σ−) also form quadruple σ2σ2π2π2 bonds in their X states. Moreover, to fill the gap existing in the current literature, here, we calculate the TcB molecule. [ABSTRACT FROM AUTHOR]

Using g‐C3N4 as semiconductor carrier, CoB particles were loaded onto the surface of g‐C3N4 to prepare CoB/g‐C3N4 photocatalyst, which exhibited improved the photocatalytic water splitting to hydrogen production performance. By comparison, it was found that bare g‐C3N4 did not produce H2, all as‐prepared CoB/g‐C3N4 photocatalysts could produce H2, and the loaded mass of CoB cocatalyst was 15 %, CoB/g‐C3N4 photocatalyst showed the highest hydrogen evolution activity. The results of work function, electrochemistry and photoelectric conversion indicated that Schottky junction was formed between CoB and g‐C3N4, which could improve the separated rate of photoinduced charge, meanwhile, loaded CoB lowed the hydrogen production overpotential of g‐C3N4. Hence, this study provides more possibilities for the application of photocatalysis. [ABSTRACT FROM AUTHOR]

Traditional morphology-based investigations of the red algal genera Devaleraea and Palmaria (Palmariaceae, Rhodophyta) fail to provide accurate accounts of diversity and distribution for species from the Russian coast of the north-western Pacific. Consequently, there is much disagreement and taxonomic uncertainty regarding several species. To resolve these issues we conducted a molecular-assisted investigation that included a DNA barcode survey (COI-5') and multilocus (COI-5', cob, psaA, ITS) phylogenetic analyses. Our analyses indicate that diversity was previously underestimated for the Devaleraea/Palmaria complex. We describe three additional species of Devaleraea: D. sakhalinensis sp. nov., D. kussakinii sp. nov. and D. urupiana sp. nov. We consider D. titlyanoviorum to be an alga with abundant proliferations from the margins, branching to several orders, that is known only from Kunashir Island. Algae from Sakhalin Island and the mainland coast of the Sea of Japan previously identified as D. titlyanoviorum are described here as D. sakhalinensis. We confirmed that the genus Palmaria is not monotypic. It includes at least two species: P. palmata in the North Atlantic and P. moniliformis in the north-western Pacific. We expand the known ranges of D. callophylloides, D. mollis and P. hecatensis in the north-western Pacific southwards and find that D. stenogona is confined to the northern part of the Sea of Japan. The distribution patterns of species of the genera Devaleraea and Palmaria are discussed in relation to the oceanography of the north-western Pacific. Three new species of the genus Devaleraea are proposed. The genus Palmaria is not monotypic and includes at least two species, P. moniliformis and P. palmata. [ABSTRACT FROM AUTHOR]

Knowledge of indoor air quality (IAQ) in cob buildings during the first few months following their delivery is of vital importance in preventing occupants' health problems. The present research focuses on evaluating IAQ in cob buildings through a prototype built in Normandy, France. To achieve this, the prototype was equipped with a set of sensors to monitor various parameters that determine indoor and outdoor air quality. These parameters include relative humidity (RH), carbon dioxide (CO2), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM1 and PM10), and volatile organic compounds (VOCs). The obtained experimental results indicate that, overall, there is good indoor air quality in the prototype building. However, there are some noteworthy findings, including high indoor RH and occasional spikes in CO2, PM1, PM10, and VOCs concentrations. The high RH is believed to be a result of the ongoing drying process of the cob walls, while the peaks in pollutants are likely to be attributed to human presence and the earthen floor deterioration. To ensure consistent good air quality, this study recommends the use of a properly sized Controlled Mechanical Ventilation system. Additionally, this study explored IAQ in the cob building from a numerical perspective. A Long Short-Term Memory (LSTM) model was developed and trained to predict pollutant concentrations inside the building. A validation test was conducted on the CO2 concentration data collected on-site, and the results indicated that the LSTM model has accurately predicted the evolution of CO2 concentration within the prototype building over an extended period. [ABSTRACT FROM AUTHOR]

Mastering construction times is of paramount importance in making vernacular earth construction techniques attractive to modern clients. The work presented here is a contribution towards the optimization of the construction time of cob buildings. Therefore, this paper follows the evolution of a cob’s mechanical properties during its drying process in the case of a double-walling CobBauge system. Laboratory tests and in situ measurements were performed, and further results were described. Volumetric water content sensors were immersed in the walls of a CobBauge prototype building during its construction. The evolution of the cob layer’s compressive strength and Clegg Impact Value (CIV) as a function of its water content has been experimentally studied and discussed. These studies showed that compressive strength and CIV are correlated with water content, and both properties decrease exponentially with time. In this study, a new tool to evaluate cob’s mechanical performances in situ has been proposed, Clegg Impact Soil Tester. This was linked to compressive strength, and a linear relationship between these two properties was found. Finally, appropriate values of compressive strength and CIV to satisfy before formwork stripping and re-lifting were proposed. For this study’s conditions, these values are reached after approximately 27 days.

This paper investigates the in situ hygrothermal behavior of a cob prototype building equipped with multiple sensors for measuring temperature, relative humidity inside the building, and water content within its walls. The experimental results show that the earth-based prototype building presents interesting thermal insulation performance. Without any heating system, the indoor temperature was found to remain stable, near 20 °C, despite large fluctuations in the outdoor temperature. This study also illustrated the ability of cob to absorb and regulate indoor relative humidity. The use of a neural network model for predicting the hygrothermal behavior of the cob prototype building was an additional objective of this work. This latter was centered on investigating the indoor ambience and moisture content within the walls. In this sense, a long short-term memory model (LSTM) was developed and trained. The validation results revealed an excellent agreement between the model predictions and experimental data, with R2 values of 0.994 for the indoor air temperature, 0.960 for the relative humidity, and 0.973, 0.925, and 0.938 for the moisture content at three different depths in the building's walls. These results indicate that the LSTM model is a promising approach for predicting the indoor ambience of an earth-based building, with potential applications in building automation and energy management. Finally, an economic discussion of the CobBauge system is presented. [ABSTRACT FROM AUTHOR]

Mastering construction times is of paramount importance in making vernacular earth construction techniques attractive to modern clients. The work presented here is a contribution towards the optimization of the construction time of cob buildings. Therefore, this paper follows the evolution of a cob's mechanical properties during its drying process in the case of a double-walling CobBauge system. Laboratory tests and in situ measurements were performed, and further results were described. Volumetric water content sensors were immersed in the walls of a CobBauge prototype building during its construction. The evolution of the cob layer's compressive strength and Clegg Impact Value (CIV) as a function of its water content has been experimentally studied and discussed. These studies showed that compressive strength and CIV are correlated with water content, and both properties decrease exponentially with time. In this study, a new tool to evaluate cob's mechanical performances in situ has been proposed, Clegg Impact Soil Tester. This was linked to compressive strength, and a linear relationship between these two properties was found. Finally, appropriate values of compressive strength and CIV to satisfy before formwork stripping and re-lifting were proposed. For this study's conditions, these values are reached after approximately 27 days. [ABSTRACT FROM AUTHOR]

In this paper, the results obtained from a series of parametric analyses, where the influence that geometric and mechanical parameters have in the structural response of existing vernacular cob walls within an Irish context, are presented. A design of experiments using central composite designs was implemented along with analysis of variance following two computational approaches, namely, the finite element method and kinematic limit analysis. As results, a series of response surfaces and parametric equations with which it is possible to compute safety factors and collapse multipliers (within the range of values studied) are provided. Based on the results obtained, it could be concluded that traditional cob walls in Ireland are very robust. Relatively high acceleration values, unlikely to happen in a low seismic hazard region such as Ireland, would be needed to start the collapse mechanisms studied or cause yielding in typical vernacular cob walls. Furthermore, the equations generated with the refined regression models can be used by practitioners as a first approach to estimate the safety levels of existing cob buildings with similar characteristics. [ABSTRACT FROM AUTHOR]

This study examined the shrinkage rate and mechanical properties of cob samples. Cob is a natural building material composed of clay, water, and varying amounts of plant fibres. The red and beige cob materials in this study containing 3% and 6% wheat fibres were manufactured by hand with clay, bulk fibres (short and long fibres), and a 25% water ratio (water/clay) in order to make their manufacture and use on construction sites feasible and simple. The reference samples were mixed with clay, 25% water, and 0% wheat fibre. The mechanical properties were assessed through compression and flexural tests after 28 and 120 days. The results showed that the fibre addition decreased the bulk density of the composites from 1902 kg/m3 to 1264 kg/m3. The compressive strength increased from 1.8 MPa to 4.57 MPa for the red clay samples and from 1.65 MPa to 4.61 MPa for the beige clay samples at 28 days. The compressive strength of each mixture decreased slightly with age for the red and beige clay samples, respectively. Conversely, the flexural strength increased with age for the samples reinforced with 3% and 6% fibres. The results also showed that the cob samples can deform without breaking. Increasing the fibre content in the mix resulted in a significant reduction in the shrinkage rate and an increase in the mass loss rate during thermogravimetric analysis. This analysis showed a total mass loss of approximately 5.64%, 6.12%, and 44.87% for the red clay, beige clay, and fibres, respectively. An average volume shrinkage of 1% was observed for the samples with 6% fibre content. The cob discussed in this article can be used as a filling material. In large quantities, it can be made by hand, with feet protected by boots, or with the use of a mixer. The environmental benefits are considerable, as the raw materials are renewable, and the manufacturing process is less energy-intensive.

The species complexes Cryptococcus neoformans and Cryptococcus gattii are the causative agents of cryptococcosis. Virulence and susceptibility to antifungals may vary within each species according to the fungal genotype. Therefore, specific and easily accessible molecular markers are required to distinguish cryptic species and/or genotypes. Group I introns are potential markers for this purpose because they are polymorphic concerning their presence and sequence. Therefore, in this study, we evaluated the presence of group I introns in the mitochondrial genes cob and cox1 in different Cryptococcus isolates. Additionally, the origin, distribution, and evolution of these introns were investigated by phylogenetic analyses, including previously sequenced introns for the mtLSU gene. Approximately 80.5% of the 36 sequenced introns presented homing endonucleases, and phylogenetic analyses revealed that introns occupying the same insertion site form monophyletic clades. This suggests that they likely share a common ancestor that invaded the site prior to species divergence. There was only one case of heterologous invasion, probably through horizontal transfer to C. decagattii (VGIV genotype) from another fungal species. Our results showed that the C. neoformans complex has fewer introns compared to C. gattii. Additionally, there is significant polymorphism in the presence and size of these elements, both among and within genotypes. As a result, it is impossible to differentiate the cryptic species using a single intron. However, it was possible to differentiate among genotypes within each species complex, by combining PCRs of mtLSU and cox1 introns, for C. neoformans species, and mtLSU and cob introns for C. gattii species. [ABSTRACT FROM AUTHOR]

The optimization of plant nutrients and irrigation regimes hold potential to boost maize growth, cob yield, herbage biomass and revenue generation of maize. A field study was conducted to optimize irrigation and fertilization management for dual-purpose maize. The experiment was comprised four irrigation regimes viz. no irrigation (I0), one irrigation 20 days after sowing (DAS) (I1), two irrigations 20 and 40 DAS (I2), and three irrigations 20, 40 and 60 DAS (I3). The fertilization regimes included a treatment with recommended dose of fertilizers (RDF) (275-125-80-125-8 kg ha-1 of nitrogen, phosphorous, potassium, gypsum and sulfur) (F1), poultry manure (PM) (5 t ha-1) (F2), 75% RDF + PM (2.5 t ha-1) (F3), and 50% RDF + PM (5 t ha-1) (F4). Combination of I3 and F3 outperformed other treatment combinations in terms of most of the yield attributes such as plant height (177.72 cm), cob length with (8.36 cm) and without husk (1.62 cm), and cob (without husk) yield (3.86 t ha-1). This treatment combination also produced maize with the highest protein content of leaves and cobs. However, the highest green herbage yield (29.99 t ha-1) was recorded with I1×F1, which remained at par with I1×F3. It took 20 additional days for crop switching from fodder harvest to attain baby corn maturity. The economic analysis revealed that I3×F3 treatment combination generated the greatest economic revenue. [ABSTRACT FROM AUTHOR]

The benefits of using earthen material such as cob in architecture are increasingly acknowledged, yet remaining concerns about safety prevent its broader use. This is particularly true in areas that experience earthquakes and heavy rain. To better understand the structural characteristics of cob in such harsh environmental conditions, this study examines cob structures found in rural areas of Japan, which are subject to those conditions. On average, we found they have been standing for 80 years. First, through interviews and surveys, this study verifies that amateurs built these structures; that is, they were built under worst-case scenarios for quality control. Second and mainly, field work measurements provide data to show deterioration patterns over decades, and sometimes centuries. Major findings were as follows. As expected, the bottom of the walls is most susceptible to deterioration. Unexpectedly, the data appears to show that deterioration is minimized when foundations are short, using small stones, 80 mm to 140 mm in height. The average deterioration at the bottom for walls with tall foundations (150 mm in height and over) is 64 mm, and for walls with a short foundation is 25 mm.

The study of maize plant productivity for hybrids Zorianyi FAO190, Leleka FAO 260, Donor MV FAO 310 with seeding rates of 60-90 thousand seeds per hectare was carried out during 2018-2020 in the North-Eastern Forest Steppe of Ukraine (Sumy district). It was found that such index as number of rows in a cob and number of grains in a row depends more on hybrid characteristics than on seeding rate. With density increase of the crops, occurs a decrease in grain number in a row. Weather conditions have a significant effect on grain number and, accordingly, the yield of maize grain. We can recommend usage of seeding rate of 90.000 seeds per hectare for hybrids Zorianyi, for Leleka 80.000 seeds and 70.000 seeds per hectare for hybrid Donor MV. [ABSTRACT FROM AUTHOR]

This study focuses on the drying kinetics of cob and light-earth layers comprising a hybrid walling system. Volumetric water content sensors are immersed and placed at different positions on the walls of a building to measure the drying kinetics. In addition, an experimental analysis of the effect of temperature, relative humidity (RH), and wind velocity variations on thermal conductivity in a climatic chamber under winter and summer conditions was conducted. The analysis of samples in laboratory aims to investigate the hygrothermal properties of cob and light-earth materials, and their dependency on the aforementioned parameters. The in situ drying kinetics of both materials involves water content reduction and stabilization; however, in the laboratory, although the water content of materials decreases, the drying is incomplete. Which may be due to the limited wind speed. The hydrothermal properties show that open porosity affects water vapor permeability and modifies the RH of cob and light-earth. At 23 °C, when the relative humidity (RH) range was 10–30%, the absorbed water vapor of cob and light earth was 0–2%. However, when the RH is 40–90%, the absorbed water vapor of light earth (2–9%) exceeds that of cob (0.5–2%). Moreover, the response to relative humidity (RH) with regard to the mixing law of components and samples differs. The resistance factor to water vapor diffusion values for cob and light-earth are 12.9 and 8.2, respectively. In this study, the thermal conductivity measurements under summer and winter conditions provide the relationship between the thermal conductivity, density, and water content of cob and light-earth materials.

Earthen structures have an important representation among the UNESCO World Heritage List sites as well as among the built environment in general. Unfortunately, earthen heritage structures are also numerous within the UNESCO List of World Heritage in Danger whereas other existing common earthen structures are extremely vulnerable to seismic and climate change events. Within the field of heritage conservation, structural analysis contributes to the safety evaluation of the structure, the diagnosis of the causes of damage and decay, and to the validation of interventions. Thus, the need to develop effective and accurate computational methods suitable for the study of both monumental and vernacular earthen structures becomes evident. This paper compiles, summarizes, and highlights the latest developments and implementations of computational methods for the study of such structure typologies. The literature has been explored following the PRISMA-S checklist methodology and a narrative synthesis was used for the presentation of results. Finally, future trends, opportunities, and challenges are discussed.

The population of developed nations spends a significant amount of time indoors, and the implications of poor indoor air quality (IAQ) on human health are substantial. Many premature deaths attributed to exposure to indoor air pollutants result from diseases exacerbated by poor indoor air. CO2, one of these pollutants, is the most prevalent and often serves as an indicator of IAQ. Indoor CO2 concentrations can be significantly higher than outdoor levels due to human respiration and activity. The primary objective of this research was to numerically investigate the indoor relative humidity and CO2 in cob buildings through the CobBauge prototype, particularly during the first months following the building delivery. Both in situ experimental studies and numerical predictions using an artificial neural network were conducted for this purpose. The study presented the use of a piecewise autoregressive exogenous model (PWARX) for indoor relative humidity (RH) and CO2 content in a building constructed with a double walling system consisting of cob and light earth. The model was validated using experimental data collected over a 27-day period, during which indoor RH and CO2 levels were measured alongside external conditions. The results indicate that the PWARX model accurately predicted RH levels and categorized them into distinct states based on moisture content within materials and external conditions. However, while the model accurately predicted indoor CO2 levels, it faced challenges in finely classifying them due to the complex interplay of factors influencing CO2 levels in indoor environments.

Knowledge of indoor air quality (IAQ) in cob buildings during the first few months following their delivery is of vital importance in preventing occupants’ health problems. The present research focuses on evaluating IAQ in cob buildings through a prototype built in Normandy, France. To achieve this, the prototype was equipped with a set of sensors to monitor various parameters that determine indoor and outdoor air quality. These parameters include relative humidity (RH), carbon dioxide (CO2), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM1 and PM10), and volatile organic compounds (VOCs). The obtained experimental results indicate that, overall, there is good indoor air quality in the prototype building. However, there are some noteworthy findings, including high indoor RH and occasional spikes in CO2, PM1, PM10, and VOCs concentrations. The high RH is believed to be a result of the ongoing drying process of the cob walls, while the peaks in pollutants are likely to be attributed to human presence and the earthen floor deterioration. To ensure consistent good air quality, this study recommends the use of a properly sized Controlled Mechanical Ventilation system. Additionally, this study explored IAQ in the cob building from a numerical perspective. A Long Short-Term Memory (LSTM) model was developed and trained to predict pollutant concentrations inside the building. A validation test was conducted on the CO2 concentration data collected on-site, and the results indicated that the LSTM model has accurately predicted the evolution of CO2 concentration within the prototype building over an extended period.

Sodium borohydride (NaBH 4) has been proposed to be a realizable hydrogen supplier for proton-exchange membrane fuel cell. Cobalt boride (CoB) is one of the most promising non-precious metal-based catalysts toward NaBH 4 hydrolysis. In this work, we develop a facile method to synthesize defects-rich TiO 2 supported CoB nanoparticles (CoB/TiO 2- x). In this CoB/TiO 2- x , an electronic metal-support interaction is induced by transferring electrons from the defective TiO 2 to CoB to form electron-rich CoB particles, facilitating the hydrolysis of NaBH 4. The as-synthesized CoB/TiO 2- x catalyst shows a good catalytic performance with hydrogen generation rate of 3070 mL min−1 g Co −1 and activation energy of 57.03 kJ mol−1. • A one-step and facial method was developed to prepare defect-rich TiO 2 supported CoB for NaBH 4 hydrolysis. • TiO 2 with in-situ evolved defects offers more effective anchoring sites to disperse CoB nanoparticles. • Electronic interaction between defected-TiO 2 and CoB was unveiled to enhance the catalytic activity. • Detailed kinetics study was performed for the NaBH 4 hydrolysis catalyzed by CoB/TiO 2- x. [ABSTRACT FROM AUTHOR]

We assessed the range of morphological variation in Devaleraea mollis from the Northwest Pacific. Genetic analyses based on the 5' end of the genes coding for cytochrome c oxidase I (COI-5'), cytochrome oxidase b (cob) and photosystem I reaction centre apoprotein A1 (psaA), as well as the ITS1–5.8S–ITS2 (ITS) fragment of rDNA, revealed that the morphospecies D. mollis includes two species. The alga from Japan previously identified as 'Palmaria palmata' resolved as sister to D. stenogona and is here described as D. inkyuleei sp. nov. The species is morphologically similar to D. mollis, but it has a more southern range. Devaleraea inkyuleei is only known from Japan (Honshu and Hokkaido) and from Aniva Bay (Sakhalin Island, Russia). [ABSTRACT FROM AUTHOR]

Phytosterols are important structural components of plant cells that affect membrane fluidity, permeability, and membrane-related metabolic regulation. These compounds, which are abundant in vegetable oils and corn kernel oil, are also beneficial for human health. Cultivation of corn (Zea mays L.) produces huge amounts of cobs as a by-product, but efforts to utilize cobs are still limited. Here, we investigated phytosterol, crude oil, and fatty acid contents in the kernels and cobs of four major corn cultivars in South Korea and explored the potential use of cobs as a source of phytosterols. Total phytosterol levels were two times higher in cobs (68.0–217.1 mg 100 g−1 DW) than in kernels (43.8–89.5 mg 100 g−1 DW) and were highest in the kernels and cobs of Sinhwangok at 60 days after pollination. We showed that not only kernels but also cobs can be a rich source of phytosterols. The results also revealed that the amount of phytosterol is depending on a genetic background as well as developmental stages suggesting further investigation would enhance the utilization of corn cobs as a phytosterol source. [ABSTRACT FROM AUTHOR]

The article shows the stages of breeding work to create a variety of white-grain Adygeiskaya corn. In order to collect, study and preserve local populations, the Institute researchers traveled to various auls and villages of Adygea. The studies were carried out in accordance with generally accepted methods of breeding work with corn. In the course of the research, the task was solved to reduce the height of plants to 2.0 m, to resist to lodging, fragility of the stem and loose smut, to increase productivity. For the period of 1999–2000 75% of the original material was rejected. In subsequent years, to increase the efficiency of selection, elite cobs were selected in the amount of 50–100 pieces after additional rejection in laboratory conditions and were sown by families. In 2007, the line AB-73 was allocated, which received the name Adygeiskaya. The new variety showed a grain yield of 60.8–71.0 centners/ha, which is 12.2 centners/ha higher than the Urvanskaya white standard, the yield of grain from the cob was 82.0%, the standard – 81.3%. Its grain is distinguished by good quality indicators: fat – 5.0%, protein – 11.9%. The variety has passed production testing in the fields of Adygea, the Krasnodar Territory and the Republic of Abkhazia. Approved for the use since 2009. High productivity and adaptability of the variety allow us to recommend it for wide use in production. The creation of the white-grain Adygeiskaya corn variety is a significant step in expanding the range of varieties used in production, as well as a contribution to the formation of a modern strategy for the scientific and technological development of the Russian Federation, the results of scientific research are important for the development of the theory and practice of breeding work.

Maize, one of the most important crops in the food chain, is facing severe threats from the escalating incidence of drought stress worldwide. Maize grain development requires assimilate uptake from the attached cob, however, the spatial distribution of sugars (the main carbon assimilate) within ear and its relationship with grain development under drought stress remain unclear. Here, we systematically investigated the dynamics of sugars and starch in different sub-tissues of cob (pith, woody ring, pedicel, and glume) and grain at different regions (the apical, middle and basal) of the developing ear under drought stress during grain filling. Results showed that the major sugar within cob was sucrose, followed by hexoses (fructose and glucose) and starch. Spatially, sucrose was highest in the woody ring and decreased toward the pedicel and then grain, whilst the hexoses were higher in the grain and then the cob center (pith) but gradually decreased towards the pedicel. Under drought, sucrose and hexoses were significantly accumulated in the pedicel but reduced in the grain, revealing that sugar uptake from the pedicel by grain was blocked. Moreover, sugars were reduced in the apical and middle regions of cob but were promoted in the basal region by drought, suggesting a drought-suppressed sugar translocation within cob. Accordingly, grain weight in the apical, middle, and basal regions were reduced by 18.9 %, 11.3 %, and 10.8 %, with starch weight decreased by 25.2 %, 21.4 %, and 2.0 %, respectively, at maturity. Collectively, these results support that sugar uptake from the pedicel by the grain and upward translocation along the cob are associated with grain weight in response to drought. These findings firstly uncover the spatial patterns for sugars within ear to respond to drought stress and highlight the importance of sugar availability within cob in grain yield formation. • Spatial-temporal distributions of sugars in maize ear in response to drought. • Drought hinders assimilate uptake by grain from pedicel. • Drought hinders upward translocation of assimilate along the cob. • Grain weight loss is associated with stuck sugar translocation under drought. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cd 0.9 Zn 0.1 S/CoB heterojunction was constructed by multi-step method. • The CZS/CoB exhibited excellent magnetic separation property. • The photocatalytic H 2 evolution rate reached 59.1 mmol g-1h−1. • The mechanism of Schottky junction and photothermal effect was proposed. The construction of heterojunctions effectively suppresses the undesired recombination of photogenerated charge carriers. This work presents the rational design and preparation of a novel Cd 0.9 Zn 0.1 S/CoB (CZS/CoB) Schottky heterojunction tailored for photothermal-assisted photocatalytic hydrogen evolution with the aid of the predictions of density functional theory (DFT). Under visible light irradiation, the hydrogen evolution rate of CZS/CoB reaches 2.56 times that of pure CZS, due to the formed Schottky heterojunction and photothermal properties, effectively inhibiting electron-hole recombination and boosting the photocatalytic reaction. Notably, with the help of the excellent magnetic properties of CoB, the as-synthesized CZS/CoB exhibits excellent magnetic separation property, which is crucial for practical application. The charge transfer pathways in the Schottky heterojunction were confirmed by experimental results and verified by DFT calculation results. This study presents a feasible strategy for the design and preparation of magnetic recyclable Schottky Heterojunction photocatalyst for photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Earth construction promises to reduce the carbon dioxide impact of building materials, and more investigations are needed to define regions where the latter are suitable. This work aims to formulate clay materials reinforced with plant fibres in a traditional manner to determine their thermal properties for applications in modern wood-frame structures. The main objective is to manufacture cob using different types of clay, disregarding the clay/sand ratio, and to achieve a solid cob material characterized by an absence of cracks, low volumetric shrinkage, and thermal properties like those of a normal cob. The Atterberg limits of each clay and the absorption coefficient of the fibres were determined before the samples were made. Formulation of 93 samples was carried out with 15, 20, 25, and 30 % water and 0 %, 3 %, and 6 % wheat fibers by mass. Subsequently, 18 samples produced with 25 % water and 0 %, 3 %, and 6 % wheat fibres by mass were retained and used for testing. The thermal conductivity (λ), specific heat capacity (C p), thermal diffusivity (D), and thermal effusivity (E) were measured after sample drying. The study showed an improvement in thermal properties with increasing fibers in the mixtures, leading to a significant improvement in thermal performance. The clay and cob samples showed a thermal conductivity (λ) of 1.16 W/(m K) and 0.55–0.2 W/(m K), respectively. An increase in thermal capacity was observed with the samples containing fibre, while the thermal diffusivity and thermal effusivity decreased with increasing fibres in the mixtures. Single-factor ANOVA tests were used to show no significant difference between the thermal properties of red and beige clay samples. Our observation supports the idea that beige clay can be used as a finishing coating material for cob walls formulated with red clay. [Display omitted] • Samples studied were produced using the cob technique with bulk fibres. • The samples' thermal properties (conductivity, heat capacity, thermal effusivity, and diffusivity) were studied. • Data on the thermal properties obtained were evaluated by ANOVA and t-test analyses. • The addition of fibre and the type of clay significantly changed the thermal measurements. • Materials obtained are reproducible without difficulty and used for filling large-scale wooden building structures. [ABSTRACT FROM AUTHOR]

In this paper, the results obtained from a series of parametric analyses, where the influence that geometric and mechanical parameters have in the structural response of existing vernacular cob walls within an Irish context, are presented. A design of experiments using central composite designs was implemented along with analysis of variance following two computational approaches, namely, the finite element method and kinematic limit analysis. As results, a series of response surfaces and parametric equations with which it is possible to compute safety factors and collapse multipliers (within the range of values studied) are provided. Based on the results obtained, it could be concluded that traditional cob walls in Ireland are very robust. Relatively high acceleration values, unlikely to happen in a low seismic hazard region such as Ireland, would be needed to start the collapse mechanisms studied or cause yielding in typical vernacular cob walls. Furthermore, the equations generated with the refined regression models can be used by practitioners as a first approach to estimate the safety levels of existing cob buildings with similar characteristics.

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The species complexes Cryptococcus neoformans and Cryptococcus gattii are the causative agents of cryptococcosis. Virulence and susceptibility to antifungals may vary within each species according to the fungal genotype. Therefore, specific and easily accessible molecular markers are required to distinguish cryptic species and/or genotypes. Group I introns are potential markers for this purpose because they are polymorphic concerning their presence and sequence. Therefore, in this study, we evaluated the presence of group I introns in the mitochondrial genes cob and cox1 in different Cryptococcus isolates. Additionally, the origin, distribution, and evolution of these introns were investigated by phylogenetic analyses, including previously sequenced introns for the mtLSU gene. Approximately 80.5% of the 36 sequenced introns presented homing endonucleases, and phylogenetic analyses revealed that introns occupying the same insertion site form monophyletic clades. This suggests that they likely share a common ancestor that invaded the site prior to species divergence. There was only one case of heterologous invasion, probably through horizontal transfer to C. decagattii (VGIV genotype) from another fungal species. Our results showed that the C. neoformans complex has fewer introns compared to C. gattii. Additionally, there is significant polymorphism in the presence and size of these elements, both among and within genotypes. As a result, it is impossible to differentiate the cryptic species using a single intron. However, it was possible to differentiate among genotypes within each species complex, by combining PCRs of mtLSU and cox1 introns, for C. neoformans species, and mtLSU and cob introns for C. gattii species.