The Cuban industry La Purísima produces sauces and dressings for the national gastronomy; but it does not have a process for the deposition of chicken eggshells, as a result, 220 kg of eggshells are dumped daily, which generate a negative impact on the environment. The research evaluates the drying of hen eggshells with protein membrane on a laboratory scale, with a view to revalorizing this waste in the production of a calcium-rich poultry feed supplement. The calcium carbonate content of the shell was determined to confirm the potential application of the residue. The drying curve and drying rate curve was obtained by experimental measurement in a drying oven under aeration at 90 °C. The calcium carbonate content of the residue was 93,33 %. The drying curve was fitted to an exponential mathematical model as a function of the drying constant and the moisture in equilibrium at a temperature of 90 °C. The drying regime of the solid presented a period of decreasing drying rate up to a moisture value of 0,021 kg of water / kg of dry solid, for lower values, this presented a deviation from the exponential function in its rate. The utilization of residual eggshells proved to be an attractive source of calcium carbonate with potential for its use in the production of feed supplement for poultry.

RESUMEN En la Industria cubana La Purísima se producen salsas y aderezos para la gastronomía nacional; pero no dispone de un proceso para la deposición de las cáscaras de huevo de gallina, como resultado, se vierten diariamente 220 kg de cáscaras que generan un impacto negativo en el medio ambiente. La investigación evalúa el secado de las cáscaras de huevo de gallina con membrana proteica a escala de laboratorio, con vistas a revalorizar este residuo en la producción de un suplemento alimenticio para aves de corral rico en calcio. Se determinó el contenido de carbonato de calcio en la cáscara para confirmar la aplicación potencial del residuo. La curva de secado y del régimen de secado se obtuvo por medición experimental en un secadero bajo aireación a 90 °C. El contenido de carbonato de calcio en el residual fue de 93,33 %. La curva de secado se ajustó a un modelo matemático exponencial en función de la constante de secado y la humedad en equilibrio a una temperatura de 90 °C. El régimen de secado del sólido presentó un período de velocidad de secado decreciente hasta un valor de humedad de 0,021 kg de agua / kg de sólido seco, para valores inferiores presentó una desviación de la función exponencial en su velocidad. El aprovechamiento de las cáscaras de huevo residuales resultó ser una fuente atractiva de carbonato de calcio con potencialidades para su utilización en la elaboración de suplemento alimenticio para aves de corral.

RESUMEN El trabajo tuvo el propósito de caracterizar, desde el punto de vista químico, físico, granulométrico y mineralógico, un residuo industrial de hidróxido de calcio generado en el proceso de fabricación de acetileno. Las muestras se analizaron, primeramente, sin neutralizar; luego se realizó el mismo procedimiento, usando ácido sulfúrico a un 98 % de pureza. Para ambos casos, las temperaturas de calentamiento fueron de 500 oC y 900 oC. Para identificar las fases, los patrones de difracción fueron obtenidos usando fuente de radiación de cobre (CuKα, λ=1,5418 Å). Se determinó que el residual presenta CaO y MgO, lo que garantiza su pureza. Al calentarlo sin neutralizar a 500 oC se transforma el hidróxido de calcio y a los 900 oC hay pérdida del carbonato y del agua. En el residual, tanto sin tratamiento como neutralizado, está presente el hidróxido de calcio.

ABSTRACT The purpose of the work was to characterize, from the chemical, physical, granulometric and mineralogical point of view, an industrial residue of calcium hydroxide generated in the acetylene manufacturing process. Samples were first analyzed without neutralization; then the same procedure was performed using 98 % purity sulphuric acid. For both cases, the heating temperatures used were 500 °C and 900 °C. To identify the phases, diffraction patterns were obtained using copper radiation source (CuKα, λ = 1.5418 Å). It was determined that residual contains CaO and MgO, which guarantees its purity; heated at 500 °C, and without neutralizing, calcium hydroxide is transformed and there is loss of water and carbonate at 900 °C. In both untreated and neutralized waste, calcium hydroxide is present.

RESUMEN Esta investigación propone sustituir el cieno carbonatado que se utiliza como agente neutralizante en la tecnología de lixiviación ácida por los polvos residuales de la industria del mármol. El proceso de neutralización del licor en la lixiviación ácida a presión presenta concentraciones de ácido sulfúrico en exceso con valores de pH igual a 1,9 unidades, lo cual permite utilizar los residuos sólidos de carbonato de calcio de la industria del mármol. La investigación se realizó a escala de laboratorio con un régimen de agitación de 68 rpm. Se utilizó el diseño factorial multinivel, donde se estudian dos factores: la masa de sólido del agente neutralizante (1, 2, 3 y 4 g) y la temperatura (50 C y 700 C). Se evaluó, además, el comportamiento de las variables mediante el modelo cinético. Los modelos estadísticos evidenciaron una relación directa entre el aumento de la masa de sólido y la temperatura, donde el primer factor ejerce una influencia positiva en el proceso. Los mejores resultados de pH se obtienen en la prueba 1, para (50 ºC y 1 g), donde se logran valores desde 2,37 hasta 2,53, en el tiempo desde uno hasta 10 minutos.

ABSTRACT This research is a proposal for replacing carbonated silt used as neutralizing agent in acid leaching technology with residual dust from marble industry. The liquor neutralization process in pressure acid leaching contains sulfuric acid concentration to excess with pH values equal to 1.9 units, which allows using solid calcium carbonate residues from marble industry. The research was carried out at laboratory scale with an agitation regime of 68 rpm. The multilevel factorial design was used, where two factors are studied: solid mass of neutralizing agent (1, 2, 3 and 4 g) and temperature (50 ºC and 700 ºC. Behavior of variables was also assessed by means of kinetic model. The statistical models showed a direct relationship between the increase of solid in the mass and the temperature, where the first factor exerts a positive influence on the process. The best pH results are obtained in test 1, for (50 ºC and 1 g), where values from 2,37 to 2,53 are achieved between one to ten minutes.

Abstract: Utilization of microbiologically induced calcite precipitation along with fiber composite have great influence on improving strength and durable properties of concrete. The concept of mechanical properties of grouted concrete added with bacteria, steel fibers (SF), rice husk ash (RHA) and light weight aggregate (LWA) has been focused on this work. In the fabrication of concrete specimens, concentration of bacteria, combination of steel fibers and LWA was placed in the form-work, and to fill the voids flowable grout was injected. The variables studied in this work are two different sizes of LWA viz., 10 mm and 12.5 mm with constant dosage of 2% hooked end steel fibers by volume of concrete, 10% RHA was used as cement replacement for preparation of grout and bacteria was incorporated in cement grout by direct application. The prop erties such as compressive strength (CS), compressive strength regain (CSR), crack width healing, impact strength for first crack and final failure, rate of healing was studied for pre-cracked specimens using visual and microscopic observation. In addition, microstructure was studied for grouted concrete without bacteria and with bacteria under immersed curing condi tions. From the experimental results, performance of bacteria added grouted concrete properties such as CS, CSR, cracking healing capacity, and impact strength has improved with the addition of fibers

Resumo A estomatite química é um tipo de lesão traumática causada pelo contato de substâncias químicas e medicamentos com os tecidos bucais, resultando em danos clinicamente significativos. Nesse contexto, é relatado o caso de um paciente do sexo masculino com 14 anos, portador de doença renal crónica, em terapia renal substitutiva (diálise peritoneal) e uso de carbonato de cálcio via cápsulas orais para tratamento. Devido a complicações da diálise peritoneal, o paciente apresentou um quadro de peritonite bacteriana, necessitando de internamento em unidade de terapia intensiva e alteração do modo de terapia dialítica para hemodiálise. Durante o período de internamento, foi observado o desenvolvimento de lesões orais significativas devido à administração inadequada de carbonato de cálcio, interferindo na evolução do estado geral de saúde do paciente e exigindo a assistência de uma equipa odontológica para diagnóstico e tratamento. O paciente foi diagnosticado com estomatite química. Durante o exame clínico foi possível observar a presença de lesões ulceradas e hemorrágicas localizadas no lábio, mucosas jugais, palato duro e palato mole. A fotobiomodulação a laser foi utilizada como tratamento associada ao corticosteróide. Cada região recebeu dez pontos de 1 J, de forma que foram fornecidos 60 J de energia por dia/sessão. No total, foram fornecidos 480 J de energia com um tempo total de irradiação de 4800 s. O paciente relatou melhora considerável dos sintomas álgicos após a primeira sessão de fotobiomodulação a laser. Após 8 sessões, o paciente melhorou e a fotobiomodulação a laser mostrou-se eficaz no tratamento de lesões orais

Abstract Chemical stomatitis is a type of traumatic injury caused by contact of chemical substances and drugs with oral tissues, resulting in clinically significant damage. This case reports a 14-year-old male patient with chronic kidney disease on renal replacement therapy (peritoneal dialysis) and using calcium carbonate via oral capsules for treatment. Due to peritoneal dialysis complications, the patient developed bacterial peritonitis, requiring intensive care unit admission and alteration of his dialysis therapy mode to hemodialysis. During the hospitalization period, significant oral lesions developed due to inadequate calcium carbonate administration, interfering with the evolution of the patient’s general health and requiring the assistance of a dental team for diagnosis and treatment. The patient was diagnosed with chemical stomatitis. During the clinical examination, ulcerated, bleeding lesions were observed on the lip, jugal mucous membranes, hard palate, and soft palate. Laser photobiomodulation was used as a treatment associated with a topical corticosteroid. Each region received ten 1 J/point, and 60 J of energy were delivered per day/session. In total, 480 J of energy were delivered with a total irradiation time of 4800 s. The patient reported considerable improvement in pain symptoms after the first laser-photobiomodulation session. After 8 sessions, the patient had improved, and laser photobiomodulation proved effective for treating oral lesions.

ABSTRACT Concrete may develop micro cracks and contains pores, both of which are extremely undesirable since they allow water and other harmful chemicals to enter the material easily. The Bacterial Self Compacting (BSCC), which continually deposits calcite in concrete, is one efficient method for sealing fissures. Microbiologically Induced Calcite Precipitation, or MICP, is the term used to describe this occurrence. The urease enzyme assists bacteria in the deposition of calcium carbonate (CaCO3). Because it is bio-based, environmentally safe, and long-lasting, the bacterial remediation method outperforms other methods. The high pH of concrete and the mechanical forces that occur during mixing require bacteria to provide resistance. The MICP-induced concrete has become a significant topic of study for high performance building. The utilization of bacteria for the production of bacterial SCC has received very little attention in India, and the durability properties of these mixtures have also received inadequate attention. Bacterial Self-Compacting Concrete (BSCC) of M60 grade, with bacteria as admixture along with flyash and silica fume. This research is to know about the workability, mechanical properties, durability and micro analysis of bacterial self-compacting concrete. The test results shows the bacteria of size 106 shows the best results in bacterial self-compacting concrete. pores easily BSCC, BSCC , fissures Precipitation MICP occurrence CaCO3. CaCO3 CaCO . (CaCO3) biobased, biobased bio based, based bio-based safe longlasting, longlasting long lasting, lasting long-lasting methods resistance MICPinduced induced building India SelfCompacting (BSCC M M6 grade fume workability selfcompacting self compacting 10 (CaCO3 1 (CaCO

Abstract This study aimed to investigate the biogenic composition of calcium carbonate (CaCO 3) in pelagic sediments in the Santos Basin over the past 140,000 years. The content and composition of CaCO 3 in different sediment fractions were evaluated, including the bulk sample, coarse fraction (foraminifera), medium fraction (juvenile foraminifera and fragments), and fine fraction (nannofossils), to determine the contribution of each fraction to the carbonated sediment composition. We found that variations in CaCO 3 levels were closely linked to glacial and interglacial periods, with higher values during interglacial periods and lower values during glacial periods. The main factor controlling the variation in CaCO 3 was dissolution, which was mainly linked to the influx of more corrosive southern water masses. Fluctuations in CaCO 3 levels were influenced by variations in productivity and dilution caused by terrigenous sediments. Nevertheless, it is noteworthy that both processes held a relatively minor impact compared to dissolution. Productivity primarily contributed to increased dissolution rates. During periods of low sea levels, dilution by terrigenous sediments became significant (similarly, the influence of the La Plata River plume was notable). However, due to the limited presence of riverine supply in the study area, which contributes directly to major dilution influences, fluctuations in terrigenous materials were considered of lesser magnitude than those caused by dissolution. The nannofossils were found to be the largest contributor to the total CaCO 3 composition, as they were the fraction least affected by the dissolution process. Overall, our results provide insights into the factors influencing CaCO 3 accumulation in marine sediments and can be used as a tool to determine changes between climatic cycles over time. 140000 140 000 140,00 years evaluated sample foraminifera, , (foraminifera) juvenile fragments, fragments fragments) nannofossils, (nannofossils) masses Nevertheless rates similarly, similarly (similarly notable. notable . notable) However area influences process Overall time 14000 14 00 140,0 (foraminifera (nannofossils 1400 1 0 140,

ABSTRACT Concrete, the cornerstone of modern building, has certain intrinsic shortcomings, such as poor tensile strength and crack susceptibility. Thus, biomineralization appears to be a promising strategy for repairing concrete construction defects through microbial activity. The most advanced use of this novel approach is Microbiologically-Induced Calcite Precipitation (MICP). Microbial urease enzyme-catalyzed calcium carbonate precipitation is a phenomenon that can be produced in concrete mixes containing zeolite by adding bacteria. This promotes calcite formation, sealing fissures and enhancing longevity. Our study compares M25 Bacterial Concrete (BC) and Conventional Concrete (CC) for optimal mix design and performance. We show by thorough experimentation that adding zeolite and bacteria does not affect the workability of concrete mixtures. In addition, BC has better compressive strength at different curing ages because of the sealing action of calcite precipitation and the synergistic improvement of zeolite. Results show MICP boosts concrete durability and cuts maintenance costs. Our research also looks into the flexural behaviour of beams made of reinforced concrete produced by microbes, offering insights into the structural performance of these novel materials in real-world applications. Materials support SDGs by fostering sustainable production and industrial innovation. building shortcomings susceptibility Thus activity MicrobiologicallyInduced Microbiologically Induced MICP. . (MICP) enzymecatalyzed enzyme catalyzed formation longevity M M2 (BC CC (CC mixtures addition costs microbes realworld real world applications innovation (MICP

ABSTRACT Purpose: To develop a new 4/6 infarct nephrectomy (INx) model rat mimicking moderate chronic kidney disease (CKD) and to evaluate its application. Methods: We modified the conventional 5/6 INx rat model to create the 4/6 INx model by ligating the renal artery branch to induce infarction of one-third of the left kidney after right kidney removal and compared biochemically and histologically both models. To demonstrate the application of the 4/6 INx model, the effects of a supplementary compound containing calcium carbonate, chitosan, palm shell activated charcoal etc., that is effective for both CKD and its complications, were compared between both models. Results: Impairment of renal function in the 4/6 INx group was significantly more moderate than in the 5/6 INx group (P < 0.05). The 4/6 INx group showed less histological damage in kidney than in the 5/6 INx group. The supplementary compound did not improve CKD in the 5/6 INx group, but ameliorated elevation of blood urea nitrogen in the 4/6 INx group. Conclusions: We developed the 4/6 INx model, which is more moderate than the conventional 5/6 INx model. This model could potentially demonstrate the effectiveness of drugs and supplements intended to prevent CKD and its progression. Purpose 46 4 6 4/ (INx (CKD Methods 56 5 5/ onethird one third models carbonate chitosan etc etc. complications Results P 0.05. 005 0.05 . 0 05 0.05) Conclusions progression 00 0.0 0.

Resumo A crescente investigação da contaminação ambiental por cistos de Giardia spp. e seu impacto na saúde pública despertou o interesse em desenvolver métodos mais sensíveis para detectar esses protozoários, especialmente na água. No entanto, esses métodos ainda são complexos e dispendiosos. Este estudo teve como objetivo avaliar a eficiência de concentração e remoção de cistos de Giardia duodenalis usando um polímero floculante aniônico à base de acrilamida (AFP) em amostras de água de retrolavagem de filtro de uma estação de tratamento de água (ETA) localizada na cidade de Blumenau, sul do Brasil, e compará-lo com a técnica de floculação de carbonato de cálcio (CCF), rotineiramente usada em matrizes de água com alta turbidez. A taxa de recuperação média de cistos de G. duodenalis usando CCF e AFP foi de 33,33% e 43,33%, com uma redução média de turbidez de 98,39% e 98,78%, respectivamente. O uso de um polímero floculante aniônico provou ser uma alternativa eficiente para a concentração e remoção de cistos de protozoários em amostras de água com alta turbidez. É importante destacar que o desenvolvimento e a aplicação de novos estudos e estratégias que aumentem a eficiência da remoção desses organismos de matrizes ambientais complexas trariam benefícios tanto do ponto de vista da saúde pública quanto da perspectiva da saúde única. spp entanto dispendiosos (AFP ETA (ETA Blumenau Brasil comparálo compará lo CCF, , (CCF) G 3333 33 33,33 4333 43 43,33% 9839 98 39 98,39 9878 78 98,78% respectivamente única (CCF 333 3 33,3 433 4 43,33 983 9 98,3 987 7 98,78 33, 43,3 98, 98,7 43,

Abstract The increasing investigation into environmental contamination by Giardia spp. cysts and its impact on public health has spurred interest in developing more sensitive methods for detecting these protozoa, particularly in water. However, these methods remain complex and costly. This study evaluated the concentration and removal efficiency of Giardia duodenalis cysts using an acrylamide-based anionic flocculant polymer (AFP) in filter backwash water samples from a water treatment plant (WTP) located in Blumenau City, southern Brazil, and compared them with the calcium carbonate flocculation technique (CCF), which is routinely used for water matrices with high turbidity. The average recovery rates of G. duodenalis cysts using CCF and AFP were 33.33% and 43.33%, respectively, with an average turbidity reduction of 98.39% and 98.78%. The use of an anionic flocculant polymer proved to be an efficient alternative for the concentration and removal of protozoan cysts in water samples with high turbidity. It is important to highlight that the development and application of new studies and strategies aimed at increasing the efficiency of the removal of these organisms from complex environmental matrices would bring benefits to public health and promote a One Health perspective. spp protozoa However costly acrylamidebased acrylamide based (AFP WTP (WTP City Brazil CCF, , (CCF) G 3333 33 33.33 4333 43 43.33% respectively 9839 98 39 98.39 9878 78 98.78% perspective (CCF 333 3 33.3 433 4 43.33 983 9 98.3 987 7 98.78 33. 43.3 98. 98.7 43.

Abstract Some octocorals (Cnidaria, Anthozoa) can produce a sub-millimeter to a millimeter-range skeleton of calcium carbonate, known as sclerites. Sclerites have diverse morphological characters, such as size, and shape features that give them relevance as taxonomic characters at different levels. Renilla Lamarck, 1816, is a genus of the order Pennatulacea (Octocorallia), in which colonies are characterized by two distinct zones: a peduncle, which anchors them to the substrate, and a rachis that supports the polyps. In the case of Renilla muelleri Kölliker, 1872, prior research established the presence of similar sclerites in both the peduncle and the rachis. Nevertheless, the potential morphological variations of these sclerites among colonies and within different colony regions have yet to be assessed to determine the stability of these characteristics at the species level. This study aimed to describe and compare the external microscopic morphology and biometry of the sclerites of Renilla muelleri, enhancing their identification and assessing their consistency within the species. Sclerite composition was examined across the entire colony, and we analyzed length variation among colonies using generalized linear models (GLM) and within colony zones using generalized linear mixed models (GLMM). Additionally, the external microscopic morphology of all sclerites was examined through scanning electron microscopy (SEM). Based on size, two types of sclerites, namely large and small, were identified within the colonies. Both types exhibited significant size differences among colonies. Furthermore, the large sclerites displayed notable variations between zones, with those in the rachis being the largest and holding the highest rank within the colonies. In terms of external microscopic morphology, the sclerites exhibited considerable variability, making it challenging to establish clear groupings based on these characteristics. Based on the obtained results, it can be concluded that both the biometry and external microscopic morphology of sclerites do not exhibit consistency as characteristics in Renilla muelleri highlighting the ambiguity in defining Renilla species. Cnidaria, Cnidaria (Cnidaria Anthozoa submillimeter sub millimeter millimeterrange range carbonate levels Lamarck 1816 Octocorallia, Octocorallia , (Octocorallia) substrate polyps Kölliker 1872 Nevertheless level GLM (GLM GLMM. GLMM . (GLMM) Additionally SEM. SEM (SEM) small Furthermore variability results 181 (Octocorallia 187 (GLMM (SEM 18 1

Abstract Conulariids are extinct scyphozoans, have benthic and sessile life modes, and inhabited shallow marine platforms. Taphonomic studies of these animals from the Parnaíba Basin are scarce, distinctly from the Paraná Basin. The present work seeks to analyze the taphonomic characteristics of Conularia quichua from the Pimenteira Formation, Parnaíba Basin, and infer deposition events that influenced this fossiliferous concentration. The material is housed at Laboratório de Paleontologia de Macroinvertebrados (LAPALMA) and consists of 43 specimens. The taphonomic signatures used in the analyses were orientation in relation to the bedding plane, concentration, degree of preservation, and theca filling. The cluster and correspondence analyses evidenced two taphonomic classes for single-unit, fragile skeletons of conulariids from Pimenteira Formation: the taphonomic class 1 comprehends obliquely, filled, and complete skeletons; the taphonomic class 2 comprehends concordantly, fragmented, flattened, grouped, and isolated skeletons. A high-stand system tract, after the maximum transgressive surface of the Pimenteira Formation, is interpreted to be the depositional environment of this concentration, where an episodic high-energy event was responsible for the fossiliferous lens. In addition, the lack of preserved calcium carbonate shells suggests acidic conditions, assuming that diagenetic control occurred in this accumulation. scyphozoans modes platforms scarce Formation concentration LAPALMA (LAPALMA 4 specimens plane preservation filling singleunit, singleunit single unit, unit single-unit obliquely filled concordantly fragmented flattened grouped highstand high stand tract highenergy energy lens addition conditions accumulation

Resumo: Os riscos associados aos eventos climáticos são os principais responsáveis pelas perdas de produção de laranja no Brasil. No caso da citricultura de sequeiro, principalmente pelos eventos de déficit hídrico no solo, mas também para citricultura em geral, quando associados aos extremos de temperatura. O presente trabalho investigou os efeitos do manejo de água em pomar de laranjeira ‘Pera’, em condições de clima subúmido, e da aplicação de protetor solar à base de carbonato decálcio, no dossel vegetativo das plantas, visando a mitigar os efeitos dos estresses abióticosna fisiologia,produção e eficiência de uso de água de irrigação. O delineamento experimental foi em blocos casualizados, em esquema fatorial 3 x 2. Os tratamentos para o fator manejo de água: irrigação plena (100% ETc), irrigação com déficit moderado (65% ETc) eausência de irrigação; e para proteção solar: uso de protetor solar e ausência deprotetor. Houve impacto dos fatores estudados nas trocas gasosas, na qualidade de frutos e na produção do pomar. Não houve efeito isolado do manejo de água na produtividade do pomar, mas o uso do protetor solar tornou plantas de citros mais resilientes com base nastrocas gasosas,mitigando os efeitos ambientais (elevadas temperaturas e déficit hídrico),implicando em melhorias na qualidade de frutos relacionadas à massa total de frutos em plantas cultivadas sem irrigação e aumento de 12% da produtividade do pomar, independentemente do manejo de água. Os ganhos na produtividade, relacionados ao uso de protetor solar,indicam relevância da prática da proteção solar, independentemente do manejo de água do pomar na região. Resumo Brasil sequeiro solo geral temperatura ‘Pera, Pera ‘Pera , ‘Pera’ subúmido decálcio fisiologiaprodução fisiologia casualizados 2 100% 100 (100 ETc, ETc 65% 65 (65 deprotetor gasosas gasosasmitigando mitigando elevadas hídrico,implicando hídricoimplicando ,implicando implicando 12 solarindicam indicam região 10 (10 6 (6 1 (1 (

Abstract: The risks associated with climate events are the main factors responsible for sweet orange production losses in Brazil. For rainfed citrus cultivation, it is mainly due to soil water deficit, but also to citrus cultivation associated with extreme temperatures. The present study investigated the effects of water management in ‘Pera’ sweet orange orchards under sub-humid climate conditions and application of calcium carbonate-based sunscreen on the plant canopy, aiming to mitigate the effects of abiotic stresses on orchard physiology, production, and irrigation water use efficiency. The experimental design was in randomized blocks in a 3 x 2 factorial scheme. Treatments for water management factor were: full irrigation (100% ETc), irrigation with moderate deficit (65% ETc), and no irrigation; and for sunscreen protection: sunscreen use and no sunscreen. The factors have impacted gas exchange, fruit quality, and orchard yield. There was no isolated effect of soil water management on orchard productivity, but with sunscreen, citrus plants are more resilient based on gas exchange data, mitigating environmental effects (high temperatures and water deficit), resulting in improvements in fruit quality related to total fruit mass in plants grown without irrigation and with 12% increase in orchard productivity, regardless of soil water management. Productivity gains related to sunscreen indicate the need for the use of sunscreen protection regardless of soil water management in the region. Abstract Brazil ‘Pera Pera subhumid sub humid carbonatebased carbonate canopy physiology efficiency scheme were 100% 100 (100 ETc, ETc , ETc) 65% 65 (65 yield productivity data high deficit) 12 region 10 (10 6 (6 1 (1 (

Abstract. Reef-forming cnidarians are essential for maintaining ecological balance. Unfortunately, coral reefs are endangered due to coral bleaching, which interrupts mutualistic symbiosis between Symbiodiniaceae algae and their coral hosts. Bleaching events result in very high coral mortality and the rapid deterioration of reef structures. Studies aimed at explaining the causes, mechanisms, and consequences of coral bleaching have been mainly conducted with anthozoans, while the impacts of thermal stress responsible for coral bleaching have been scarcely studied in hydrozoans, such as Millepora species (phylum Cnidaria, class Hydrozoa), which are the second most important reef-forming cnidarians. In the present study, the effects of thermal stress caused by the 2015-2016 El Niño on symbiont abundance, exoskeleton structure, and the biochemical composition of Millepora alcicornis were analyzed. Unbleached M. alcicornis specimens exhibited a higher abundance of Breviolum and Durisdinium species, which suggests that unbleached hydrocoral colonies might counteract thermal stress by hosting thermotolerant symbionts of the Durisdinium genus. Bleached hydrocorals exhibited lower levels of calcification than unbleached hydrocorals as well as changes in the microstructure of trabeculae and zooid pores. In contrast, thermal stress did not affect total calcium carbonate and carbohydrate content. Bleached tissues showed significantly higher levels of protein and refractory material, whereas their lipid content decreased considerably. The present study provides evidence that bleached M. alcicornis colonies suffered a decline in calcification and changes in the structure of their exoskeletons after being exposed to the 2015-2016 El Niño. The significant decrease in lipid content suggests that M. alcicornis primarily uses energy stores to maintain vital cellular processes at the expense of calcification.

Resumen. Los cnidarios formadores de arrecifes son esenciales en la ecología marina. Desafortunadamente, están amenazados por el fenómeno de blanqueamiento, el cual rompe la simbiosis mutualista entre algas de la familia Symbiodiniaceae y sus hospederos coralinos. El blanqueamiento causa un alto índice de mortalidad de corales y un rápido deterioro de las estructuras arrecifales. Los estudios dirigidos a explicar causas, mecanismos y consecuencias del blanqueamiento se han realizado principalmente con antozoos, mientras que los impactos del blanqueamiento de corales se han estudiado escasamente en especies de Millepora (phylum Cnidaria, clase Hydrozoa), que son los segundos constructores de arrecifes más importantes. En el presente estudio se analizó el efecto del estrés térmico causado por el evento El Niño 2015-2016 sobre la abundancia de simbiontes, la estructura del exoesqueleto y la composición bioquímica de Millepora alcicornis. Los especímenes sin blanquear de M. alcicornis contenían una mayor abundancia de especies de Breviolum y Durisdinium, lo que sugiere que las colonias de hidrocorales sin blanquear podrían estar contrarrestando el estrés térmico al albergar simbiontes termotolerantes del género Durisdinium. Los hidrocorales blanqueados mostraron niveles más bajos de calcificación y cambios en la microestructura de zooides y trabéculas. En contraste, el estrés térmico no modificó el contenido total de carbonato de calcio y carbohidratos en los hidrocorales. Los tejidos blanqueados mostraron niveles significativamente más altos de proteína y material refractario, mientras que su contenido de lípidos disminuyó considerablemente. El presente estudio muestra que las colonias blanqueadas de M. alcicornis sufrieron una disminución en la calcificación y cambios en la estructura de su exoesqueleto después de estar expuestas al estrés térmico provocado por el evento El Niño 2015-2016. La disminución significativa en el contenido de lípidos sugiere que M. alcicornis está utilizando sus reservas de energía principalmente para mantener sus procesos celulares vitales a expensas de la calcificación.

Summary: The hydrological region 21 coast of Oaxaca has an active tourist dynamic, it generates significant economic income, and it is considered the fourth most important socioeconomic region in the state of Oaxaca. Similarly, hydrological region 23 coast of Chiapas, has an economy governed by tertiary sector activities and is comprised of the Istmo-Costa and Soconusco socioeconomic regions, the latter is the main region that contributes to the gross domestic product of the state of Chiapas. It should be noted that this socioeconomic growth has required a greater demand for water resources, which has led to water pollution. The deterioration of the area’s water resources is caused by the discharge of wastewater, solid waste and agrochemicals into natural waterways. In order to assess the state of the water resources of hydrological regions 21 and 23, 31 sampling sites were established in the spring of 2021 distributed in the main streams. Each sample was analyzed for chemical properties: pH, electrical conductivity (EC), major anions and cations (CO3 2-, HCO3-, Cl-, SO4 2-, Ca2+, Mg2+, Na+ and K+), total dissolved solids (TDS), percentage of sodium (%Na), adsorption ratio of sodium (RAS), residual sodium carbonate (RSC), permeability index (PI), as well as a hydrochemical evaluation. The waters of the hydrological regions 21 and 23 present as dominant facies the calcium-magnesium bicarbonate, whose possible origin is a consequence of the dilution process of the geological material (water-rock interaction) with low and medium concentrations. With respect to salinity, 45.16% are low salinity waters and 93.55% of the sites have low sodium, therefore, they are considered recommended for irrigation with moderate restrictions.

Resumen: La región hidrológica 21 costa de Oaxaca, presenta una activa dinámica turística, en ella se genera un ingreso económico importante y es considerada la cuarta región socioeconómica más importante del estado de Oaxaca. De igual manera, la Región Hidrológica 23 costa de Chiapas, tiene una economía regida por las actividades del sector terciario, está comprendida por las regiones socioeconómicas Istmo-Costa y Soconusco, ésta última es la principal región que aporta al producto interno bruto del estado de Chiapas. Cabe señalar, que dicho crecimiento socioeconómico ha exigido una mayor demanda del recurso agua, que ha ocasionado la contaminación del mismo. El deterioro de los recursos hídricos de la zona tiene su origen en la descarga de aguas residuales, de desechos sólidos y de agroquímicos a los cauces naturales. Con la finalidad de valorar el estado de los recursos hídricos de las regiones hidrológicas 21 y 23, se establecieron 31 sitios de muestreo en la primavera de 2021 distribuidos en las corrientes principales. En cada muestra se analizaron las propiedades químicas: pH, conductividad eléctrica (CE), aniones y cationes principales (CO3 2-, HCO3-, Cl-, SO4 2-, Ca2+, Mg2+, Na+ y K+), sólidos totales disueltos (STD), porcentaje de sodio (%Na), relación de adsorción de sodio (RAS), carbonato de sodio residual (CSR) e índice de permeabilidad (IP), así como una evaluación hidroquímica. Las aguas de las regiones hidrológicas 21 y 23 presentan como facie dominante la bicarbonatada cálcico-magnésica, cuyo posible origen es consecuencia del proceso de dilución del material geológico (interacción agua-roca) con concentraciones bajas y medias. Con respecto a la salinidad el 45.16% son aguas de salinidad baja y el 93.55% de los sitios tiene baja sodicidad, por lo tanto, se consideran recomendables para el riego con restricciones moderadas.