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Abstract In humans, blood Classical CD14+ monocytes contribute to host defense by secreting large amounts of pro-inflammatory cytokines. Their aberrant activity causes hyper-inflammation and life-threatening cytokine storms, while dysfunctional monocytes are associated with ‘immunoparalysis’, a state of immune hypo responsiveness and reduced pro-inflammatory gene expression, predisposing individuals to opportunistic infections. Understanding how monocyte functions are regulated is critical to prevent these harmful outcomes. We reveal platelets’ vital role in the pro-inflammatory cytokine responses of human monocytes. Naturally low platelet counts in patients with immune thrombocytopenia or removal of platelets from healthy monocytes result in monocyte immunoparalysis, marked by impaired cytokine response to immune challenge and weakened host defense transcriptional programs. Remarkably, supplementing monocytes with fresh platelets reverses these conditions. We discovered that platelets serve as reservoirs of key cytokine transcription regulators, such as NF-κB and MAPK p38, and pinpointed the enrichment of platelet NF-κB2 in human monocytes by proteomics. Platelets proportionally restore impaired cytokine production in human monocytes lacking MAPK p38α, NF-κB p65, and NF-κB2. We uncovered a vesicle-mediated platelet-monocyte-propagation of inflammatory transcription regulators, positioning platelets as central checkpoints in monocyte inflammation.

This research aims to describe the effect of changing control of the reconstruction on Sangasanga-Dondang road, Kutai Kartanegara Regency that have an impact on the time and cost. The length of the road is ± 18.02 km, starting from the intersection of three Sanga Sanga sub-districts and ending at the Dondang Bridge. The road often receives traffic loads from light vehicles and heavy vehicles. This disrupted the stability of the road structure so that some of the road segments experienced structural damage.This research used Earned Value Analysis (EVA), this method used three paramaters, namely Planned Value (PV), Earned Value (EV), and Actual Cost (AC). Based on analysis that had been done when a deviation occurs at estimate the project completion time for 36 weeks. From the parameters, the result obtained were earned value analysis was carried out in 2 weeks with BCWS value of Rp. 73,628,055.56, BCWP value of Rp. 214,691,666.67, and the ACWP value is Rp. 15,099,335,843.68.

Abstract Inflammasomes sense intracellular clues of infection, damage, or metabolic imbalances. Activated inflammasome sensors polymerize the adaptor ASC into micron‐sized “specks” to maximize caspase‐1 activation and the maturation of IL‐1 cytokines. Caspase‐1 also drives pyroptosis, a lytic cell death characterized by leakage of intracellular content to the extracellular space. ASC specks are released among cytosolic content, and accumulate in tissues of patients with chronic inflammation. However, if extracellular ASC specks contribute to disease, or are merely inert remnants of cell death remains unknown. Here, we show that camelid‐derived nanobodies against ASC (VHHASC) target and disassemble post‐pyroptotic inflammasomes, neutralizing their prionoid, and inflammatory functions. Notably, pyroptosis‐driven membrane perforation and exposure of ASC specks to the extracellular environment allowed VHHASC to target inflammasomes while preserving pre‐pyroptotic IL‐1β release, essential to host defense. Systemically administrated mouse‐specific VHHASC attenuated inflammation and clinical gout, and antigen‐induced arthritis disease. Hence, VHHASC neutralized post‐pyroptotic inflammasomes revealing a previously unappreciated role for these complexes in disease. VHHASC are the first biologicals that disassemble pre‐formed inflammasomes while preserving their functions in host defense.

Efficient mouse models to study SARS-CoV-2 infection are critical for the development and assessment of vaccines and therapeutic approaches to mitigate the current pandemic and prevent reemergence of COVID-19. While the first generation of mouse models allowed SARS-CoV-2 infection and pathogenesis, they relied on ectopic expression and non-physiological levels of human angiotensin-converting enzyme 2 (hACE2). Here we generated a mouse model carrying the minimal set of modifications necessary for productive infection with multiple strains of SARS-CoV-2. Substitution of only three amino acids in the otherwise native mouse Ace2 locus (Ace2TripleMutant or Ace2™), was sufficient to render mice susceptible to both SARS-CoV-2 strains USA-WA1/2020 and B.1.1.529 (Omicron). Infected Ace2™ mice exhibited weight loss and lung damage and inflammation, similar to COVID-19 patients. Previous exposure to USA-WA1/2020 or mRNA vaccination generated memory B cells that participated in plasmablast responses during breakthrough B.1.1.529 infection. Thus, the Ace2™ mouse replicates human disease after SARS-CoV-2 infection and provides a tool to study immune responses to sequential infections in mice.

Rotary kilns are central equipment in material processing operations such as oxide ore reduction, clinker manufacturing, and hazardous waste incineration. This work focuses on an industrial-scale rotary kiln for Ferronickel production via the Rotary Kiln-Electric Furnace (RKEF) process. Rotary kilns are prone to mechanical failure exacerbated by thermal effects, mainly during transient operation, such as preheating and cooling. However, few studies have tackled the impact of the transient operation on the stress state in the rotary kiln wall. Therefore, we evaluate the thermal and mechanical behavior of the rotary kiln wall during preheating. Actual operation data and a thermal model enable to obtain the temperature distribution along the kiln length. This temperature distribution is the starting point for calculating the stress state of the shell and refractory. The maximal thermal gradient occurs at 10 m from the hot end, with temperatures at the outer and inner surfaces of 200 °C and 820 °C, respectively. The von Mises stress shows a maximum of 121 MPa at the wheel position in the hot region of the refractory and a range of 30–60 MPa in the shell. In addition, the compressive stress is higher than the ultimate compressive strength of the refractory. However, it does not necessarily represent refractory detachment due to the plastic deformation undergone by the refractory under high temperatures. This work paves the way towards developing a tool for accurately predicting rotary kiln mechanical failure, which can help optimize operating conditions and assist in programming maintenance.

Abstract Background Low molecular weight carrageenan (Cg) is a seaweed-derived sulfated polysaccharide widely used as inflammatory stimulus in preclinical studies. However, the molecular mechanisms of Cg-induced inflammation are not fully elucidated. The present study aimed to investigate the molecular basis involved in Cg-induced macrophages activation and cytokines production. Methods Primary culture of mouse peritoneal macrophages were stimulated with Kappa Cg. The supernatant and cell lysate were used for ELISA, western blotting, immunofluorescence. Cg-induced mouse colitis was also developed. Results Here we show that Cg activates peritoneal macrophages to produce pro-inflammatory cytokines such as TNF and IL-1β. While Cg-induced TNF production/secretion depends on TLR4/MyD88 signaling, the production of pro-IL-1β relies on TLR4/TRIF/SYK/reactive oxygen species (ROS) signaling pathway. The maturation of pro-IL1β into IL-1β is dependent on canonical NLRP3 inflammasome activation via Pannexin-1/P2X7/K+ efflux signaling. In vivo, Cg-induced colitis was reduced in mice in the absence of NLRP3 inflammasome components. Conclusions In conclusion, we unravel a critical role of the NLRP3 inflammasome in Cg-induced pro-inflammatory cytokines production and colitis, which is an important discovery on the pro-inflammatory properties of this sulfated polysaccharide for pre-clinical studies. Video abstract Graphical Abstract Carrageenan (Cg) is one the most used flogistic stimulus in preclinical studies. Nevertheless, the molecular basis of Cg-induced inflammation is not totally elucidated. Herein, Lopes et al. unraveled the molecular basis for Cg-induced macrophages production of biological active IL-1β. The Cg-stimulated macrophages produces pro-IL-1β depends on TLR4/TRIF/Syk/ROS, whereas its processing into mature IL-1β is dependent on the canonical NLRP3 inflammasome.

Currently, few experimental methods exist that enable the mechanical characterization of adhesives under high strain rates. One such method is the Split Hopkinson Bar (SHB) test. The mechanical characterization of adhesives is performed using different specimen configurations, such as Single Lap Joint (SLJ) specimens. A gripping system, attached to the bars through threading, was conceived to enable the testing of SLJs. An optimization study for selecting the best thread was performed, analyzing the thread type, the nominal diameter, and the thread pitch. Afterwards, the gripping system geometry was numerically evaluated. The optimal threaded connection for the specimen consists of a trapezoidal thread with a 14 mm diameter and a 2 mm thread pitch. To validate the gripping system, the load–displacement (P−δ) curve of an SLJ, which was simulated as if it were tested on the SHB apparatus, was compared with an analogous curve from a validated drop-weight test numerical model.

We compute the spectrum of pure spin current injection in ferroelectric single-layer SnS, SnSe, GeS, and GeSe. The formalism takes into account the coherent spin dynamics of optically excited conduction states split in energy by spin–orbit coupling. The velocity of the electron’s spins is calculated as a function of incoming photon energy and angle of linearly polarized light within a full electronic band structure scheme using density functional theory. We find peak speeds of 520, 360, 270 and 370 Km s ^−1 for SnS, SnSe, GeS and GeSe, respectively which are an order of magnitude larger than those found in bulk semiconductors, e.g., GaAs and CdSe. Interestingly, the spin velocity is almost independent of the direction of polarization of light in a range of photon energies. Our results demonstrate that single-layer SnS, SnSe, GeS and GeSe are candidates to produce on demand spin-current in spintronics applications.

Severe thrombocytopenia can be a determinant factor in the morbidity of Plasmodium vivax, the most widespread human malaria parasite. Although immune mechanisms may drive P. vivax-induced severe thrombocytopenia (PvST), the current data on the cytokine landscape in PvST is scarce and often conflicting. Here, we hypothesized that the analysis of the bidirectional circuit of inflammatory mediators and their regulatory miRNAs would lead to a better understanding of the mechanisms underlying PvST. For that, we combined Luminex proteomics, NanoString miRNA quantification, and machine learning to evaluate an extensive array of plasma mediators in uncomplicated P. vivax patients with different degrees of thrombocytopenia. Unsupervised clustering analysis identified a set of PvST-linked inflammatory (CXCL10, CCL4, and IL-18) and regulatory (IL-10, IL-1Ra, HGF) mediators. Among the mediators associated with PvST, IL-6 and IL-8 were critical to discriminate P. vivax subgroups, while CCL2 and IFN-γ from healthy controls. Supervised machine learning spotlighted IL-10 in P. vivax-mediated thrombocytopenia and provided evidence for a potential signaling route involving IL-8 and HGF. Finally, we identified a set of miRNAs capable of modulating these signaling pathways. In conclusion, the results place IL-10 and IL-8/HGF in the center of PvST and propose investigating these signaling pathways across the spectrum of malaria infections.

Parkinson’s disease (PD) is the second most common age-related neurodegenerative disease. Accumulating evidence demonstrates that alpha-synuclein (α-Syn), an apparently predominant neuronal protein, is a major contributor to PD pathology. As α-Syn is also highly abundant in blood, particularly in red blood cells (RBCs) and platelets, this in turn raises the question on the function of presumably dysfunctional α-Syn in “peripheral” cells and its putative effect on the other enclosed constituents. Herein, we detected the internal variance in erythrocytes of PD patients by Raman spectroscopy, but no measurable amount of erythrocytic behavioural change (eryptosis) or any haemoglobin variation was noticed. An elevated level of plasmin-antiplasmin complexes (PAP) was observed in the plasma of PD patients, indicating activation of the fibrinolytic system, but platelet activation after thrombin stimulation was not altered. Sex-specific patterns were noticed for blood coagulation factor XIII and factor XII activity in PD patients. Additionally, the alterations in homocysteine levels which have often been observed in PD patients were found to be independent from L-DOPA usage and PAP levels. Furthermore, a selective gene expression analysis identified subsets of genes related to different blood-associated compartments (RBCs, platelets, coagulation-fibrinolysis) also involved in PD-related pathways.

Romero, J. H., Palacios, O. L., & Escobar, B. S. (julio-agosto, 2017). Estimación de la sobreexplotación producida en el acuífero Valle de Celaya (México). Tecnología y Ciencias del Agua, 8(4), 127-138. El acuífero Valle de Celaya se encuentra ubicado en el estado de Guanajuato, México, en una región denominada “El Bajío” y es la principal fuente de abastecimiento de agua de once municipios (Apaseo el Alto, Apaseo el Grande, Celaya, Comonfort, Cortázar, Jaral del Progreso, Juventino Rosas, San Miguel Allende, Salamanca, Tarimoro y Villagrán), con una población aproximada de un millón de habitantes. El desarrollo de estos municipios depende en buena medida del manejo sustentable de los recursos hídricos, sobre los cuales existe una zona de veda desde 1949. Dados los grandes cambios observados en esta región, es necesario actualizar el estudio hidrológico existente, ya que además se han modificado los límites del acuífero, el cual se fusionó con el acuífero de los Apaseos en el año 2003. El objetivo de este trabajo fue estimar el grado de sobreexplotación para el año 2013, como paso indispensable para elaborar un plan de manejo sustentable, para lo cual se aplicaron dos métodos: a) el método de balance hidrológico, que consiste en medir o calcular las diferencias entre las entradas y salidas del agua del acuífero, y b) el método de análisis de la evolución de niveles de agua, donde la sobreexplotación se determina a partir del producto del abatimiento medio en un tiempo dado, multiplicado por el coeficiente de almacenamiento. Como resultado de la aplicación del primer método se obtuvo una sobreexplotación de 440.78 Mm3 mientras por el método de evolución de niveles de agua se obtuvo una cifra de 386.58 Mm3. Sin embargo, ambos valores son sólo crudas estimaciones de la sobreexplotación real debido a la falta de información actualizada del censo de aprovechamientos y a la escasez de información geohidrológica; tampoco se cuenta con datos reales ni del gradiente hidráulico ni del valor de la transmisividad en la periferia del acuífero, parámetros indispensables para calcular las entradas y salidas horizontales mediante la ley de Darcy.

Este artículo tiene como objetivo presentar el trabajo realizado en los últimos años en el campo de metamateriales nanoestructurados. Se muestran principalmente los trabajos realizados en el Centro de Investigaciones en Óptica A. C. en conjunto con el Instituto de Física de la UNAM. Estos trabajos se han centrado en el desarrollo de nuevos modelos teóricos que permitan explicar las propiedades ópticas de sistemas nanoestructurados. Además, dichos modelos se han implementado dentro de paquetes computacionales de alto rendimiento, lo cual ha posibilitado la realización de cálculos numéricos precisos, mismos que permiten conocer las cantidades físicas con las que se puede caracterizar un material; en este caso, metamateriales nanoestructurados. Mayoritariamente, dichos cálculos numéricos se han centrado en el cómputo de la función dieléctrica y la susceptibilidad no lineal, siendo de suma importancia poder predecir su valor de forma precisa por ser dos cantidades fundamentales en el entendimiento de la interacción de la luz con la materia. Además de este desarrollo teórico-numérico, se muestran algunos resultados importantes obtenidos a lo largo de este tiempo, donde se puede observar la versatilidad y flexibilidad de los cálculos así como la importancia de contar con dichas metodologías en la predicción, descripción y diseño de materiales “a la medida” de las necesidades. Por último, se presentan las perspectivas a futuro de esta investigación, así como algunos de los retos más importantes al respecto.

The role of platelets has been extensively studied in the context of coagulation and vascular integrity. Their hemostatic imbalance can lead to known conditions as atherosclerotic plaques, thrombosis, and ischemia. Nevertheless, the knowledge regarding the regulation of different cell types by platelets has been growing exponentially in the past years. Among these biological systems, the innate immune response is remarkably affected by the crosstalk with platelets. This interaction can come from the formation of platelet-leukocyte aggregates, signaling by direct contact between membrane surface molecules or by the stimulation of immune cells by soluble factors and active microparticles secreted by platelets. These ubiquitous blood components are able to sense and react to danger signals, guiding leukocytes to an injury site and providing a scaffold for the formation of extracellular traps for efficient microbial killing and clearance. Using several different mechanisms, platelets have an important task as they regulate the release of different cytokines and chemokines upon sterile or infectious damage, the expression of cell markers and regulation of cell death and survival. Therefore, platelets are more than clotting agents, but critical players within the fine inflammatory equilibrium for the host. In this review, we present pointers to a better understanding about how platelets control and modulate innate immune cells, as well as a summary of the outcome of this interaction, providing an important step for therapeutic opportunities and guidance for future research on infectious and autoimmune diseases.

MyD88 is the main adaptor molecule for TLR and IL-1R family members. Here, we demonstrated that T-cell intrinsic MyD88 signaling is required for proliferation, protection from apoptosis and expression of activation/memory genes during infection with the intracellular parasite Trypanosoma cruzi, as evidenced by transcriptome and cytometry analyses in mixed bone-marrow (BM) chimeras. The lack of direct IL-18R signaling in T cells, but not of IL-1R, phenocopied the absence of the MyD88 pathway, indicating that IL-18R is a critical MyD88-upstream pathway involved in the establishment of the Th1 response against an in vivo infection, a presently controvert subject. Accordingly, Il18r1−/− mice display lower levels of Th1 cells and are highly susceptible to infection, but can be rescued from mortality by the adoptive transfer of WT CD4+ T cells. Our findings establish the T-cell intrinsic IL-18R/MyD88 pathway as a crucial element for induction of cognate Th1 responses against an important human pathogen.

We present a generalization of the three-layer model to calculate the surface second-harmonic generation (SSGH) yield, which includes the depth dependence of the surface non-linear second-order susceptibility tensor χ(−2ω; ω, ω). This model considers that the surface is represented by three regions or layers. The first layer is a semi-infinite vacuum region with a dielectric function ϵv(ω) = 1, from where the fundamental electric field impinges on the material. The second layer is a thin layer (ℓ) of thickness d characterized by a dielectric function ϵℓ(ω), and it is in this layer where the SSHG takes place. We consider the position of χ(−2ω; ω, ω) within this surface layer. The third layer is the bulk region denoted by b and characterized by ϵb(ω). We include the effects caused by the multiple reflections of both the fundamental and the second-harmonic (SH) fields that take place within the thin layer ℓ. As a test case, we calculate χ(−2ω; ω, ω) for the Si(111)(1 × 1):H surface and present a layer-by-layer study of the susceptibility to elucidate the depth dependence of the SHG spectrum. We then use the depth-dependent three-layer model to calculate the SSHG yield and contrast the calculated spectra with experimental data. We produce improved results over previous published work, as this treatment can reproduce key spectral features, is computationally viable for many systems, and most importantly remains completely ab initio.

Effect of Aedes fluviatilis saliva on the development of Plasmodium gallinaceum experimental infection in Gallus (gallus) domesticus was studied in distinct aspects. Chickens subcutaneously infected with sporozoites in the presence of the mosquito salivary gland homogenates (SGH) showed higher levels of parasitaemia when compared to those ones that received only the sporozoites. However, the parasitaemia levels were lower among chickens previously immunized by SGH or non-infected mosquito bites compared to the controls, which did not receive saliva. High levels of anti-saliva antibodies were observed in those immunized chickens. Moreover, 53 and 102 kDa saliva proteins were recognized by sera from immunized chickens. After the sporozoite challenge, the chickens also showed significant levels of anti-sporozoite antibodies. However, the ability to generate anti-sporozoites antibodies was not correlated to the saliva immunization. Our results suggest that mosquito saliva components enhance P. gallinaceum parasite development in naive chickens. However, the prior exposure of chickens to salivary components controls the parasitemia levels in infected individuals.

Cyclic paroxysm and high fever are hallmarks of malaria and are associated with high levels of pyrogenic cytokines, including IL-1β. In this report, we describe a signature for the expression of inflammasome-related genes and caspase-1 activation in malaria. Indeed, when we infected mice, Plasmodium infection was sufficient to promote MyD88-mediated caspase-1 activation, dependent on IFN-γ-priming and the expression of inflammasome components ASC, P2X7R, NLRP3 and/or NLRP12. Pro-IL-1β expression required a second stimulation with LPS and was also dependent on IFN-γ-priming and functional TNFR1. As a consequence of Plasmodium-induced caspase-1 activation, mice produced extremely high levels of IL-1β upon a second microbial stimulus, and became hypersensitive to septic shock. Therapeutic intervention with IL-1 receptor antagonist prevented bacterial-induced lethality in rodents. Similar to mice, we observed a significantly increased frequency of circulating CD14(+)CD16(-)Caspase-1(+) and CD14(dim)CD16(+)Caspase-1(+) monocytes in peripheral blood mononuclear cells from febrile malaria patients. These cells readily produced large amounts of IL-1β after stimulation with LPS. Furthermore, we observed the presence of inflammasome complexes in monocytes from malaria patients containing either NLRP3 or NLRP12 pyroptosomes. We conclude that NLRP12/NLRP3-dependent activation of caspase-1 is likely to be a key event in mediating systemic production of IL-1β and hypersensitivity to secondary bacterial infection during malaria.

BACKGROUND: Given the increasing evidence of Plasmodium vivax infections associated with severe and fatal disease, the identification of sensitive and reliable markers for vivax severity is crucial to improve patient care. Circulating nucleic acids (CNAs) have been increasingly recognized as powerful diagnostic and prognostic tools for various inflammatory diseases and tumors as their plasma concentrations increase according to malignancy. Given the marked inflammatory status of P. vivax infection, we investigated here the usefulness of CNAs as biomarkers for malaria morbidity. METHODS AND FINDINGS: CNAs levels in plasma from twenty-one acute P. vivax malaria patients from the Brazilian Amazon and 14 malaria non-exposed healthy donors were quantified by two different methodologies: amplification of the human telomerase reverse transcriptase (hTERT) genomic sequence by quantitative real time PCR (qPCR), and the fluorometric dsDNA quantification by Pico Green. CNAs levels were significantly increased in plasma from P. vivax patients as compared to healthy donors (p

Diversos fatores contribuíram para aumentar o número de procedimentos com circulação extracopórea para neonatos e lactentes. Esses pacientes necessitam procedimentos especiais de perfus��o, fundamentos em sua fisiologia particular, nas características do seu metabolismo e na sua resposta aos desvios da homeostase, principalmente a acidose lática. São analisados os protocolos de perfusão em 110 procedimentos com parada circulatória total, para a realização da correção intracardíaca, durante a qual diversos mecanismos de injúria ao sangue foram identificados. A injúria mecânica, por ação das forças desenvolvidas na circulação artificial do sangue e nas trocas gasosas, pode danificar os elementos figurados e as proteínas do plasma sangüíneo. O contato com as superfícies do circuito extracorpóreo pode ativar os sistemas das cininas, da coagulação, da fibrinólise e do complemento, por ativação inicial do fator XII e produzir uma reação inflamatória generalizada. A produção de ácido lático pode modificar o pH ideal para a função enzimática e celular, e o superaquecimento do sangue, durante o reaquecimento, pode produzir dano ao sangue semelhante àquele causado pelos fatores físicos da circulação extracorpórea. A perfusão neonatal e de pequenos lactentes é um continuado exercício de atenção aos detalhes e respeito aos aspectos particulares da fisiologia, do metabolismo e da resposta à injúria.Newborns and small infants require special procedures of extracorporeal circulation for open heart surgery, which must be based on their specific physiological and metabolic patterns, as well as on the response to deviations of their homeostasis. The authors reviewed the protocols of cardiopulmonary bypass utilized during 100 procedures with total circulatory arrest and discuss some mechanisms by which the blood components may be damaged or injured during perfusion. Mechanical injury of solid blood components and plasma proteins are discussed; the activation of certain plasmatic systems as the coagulation, fibrinolytic and complement by the Hageman factor, which can produce a generalized inflammatory reaction is also identified; deviations of acid-base balance by excessive lactic acid production may impair enzymatic and cellular functions which can cause injury of a metabolic nature. Thermal injury may also be produced by overheating blood during rewarming if the dynamic nature of heat exchangers function is not adequately monitored. The conclusion is that neonatal perfusion represents a continuing exercise of attention to detail and must be performed with a profound respect to their specific physiology, metabolism and response to injury.

In this work we determine the one-body Greenʼs function as solution of a set of functional integro-differential equations, which relate the one-particle Greenʼs function to its functional derivative with respect to an external potential. In the same spirit as Lani et al (2012 New J. Phys. http://dx.doi.org/10.1088/1367-2630/14/1/013056 14 http://dx.doi.org/10.1088/1367-2630/14/1/013056 ), we do this in a one-point model, where the equations become ordinary differential equations (DEs) and, hence, solvable with standard techniques. This allows us to analyze several aspects of these DEs as well as of standard methods for determining the one-body Greenʼs function that are important for real systems. In particular: (i) we present a strategy to determine the physical solution among the many mathematical solutions; (ii) we assess the accuracy of an approximate DE related to the $GW$ +cumulant method by comparing it to the exact physical solution and to standard approximations such as $GW$ ; (iii) we show that the solution of the approximate DE can be improved by combining it with a screened interaction in the random-phase approximation. (iv) We demonstrate that by iterating the $GW$ Dyson equation one does not always converge to a $GW$ solution and we discuss which iterative scheme is the most suitable to avoid such errors.

We develop a formalism for the calculation of the macroscopic dielectric response of composite systems made of particles of one material embedded periodically within a matrix of another material, each of which is characterized by a well-defined dielectric function. The nature of these dielectric functions is arbitrary, and could correspond to dielectric or conducting, transparent or opaque, absorptive and dispersive materials. The geometry of the particles and the Bravais lattice of the composite are also arbitrary. Our formalism goes beyond the long-wavelength approximation as it fully incorporates retardation effects . We test our formalism through the study of the propagation of electromagnetic waves in two-dimensional photonic crystals made of periodic arrays of cylindrical holes in a dispersionless dielectric host. Our macroscopic theory yields a spatially dispersive macroscopic response which allows the calculation of the full photonic band structure of the system, as well as the characterization of its normal modes, upon substitution into the macroscopic field equations. We can also account approximately for the spatial dispersion through a local magnetic permeability and analyze the resulting dispersion relation, obtaining a region of left handedness.

Purpose: This research aimed to determine the effectiveness of different growth mindset activities using the growth mindset worktext developed by the researcher to improve students' creativity, habits of mind and mathematics performance. Method: This study was conducted in two intact classes of Grade 7 and participants were determined through match-pairing. The instruments used in this study were validated and the reliability was determined prior to the actual implementation of this study. Appropriate tools were employed in the analysis of data. Findings: Results revealed that after the intervention the students in the non-growth mindset activities group are still on the "low" level of creativity, "low" level of their habits of mind and "average" level of their mathematics performance whereas the students in the growth mindset activities group are on "slightly creative" from "low" level of creativity, "low" to "average" level of the habits of mind and "low" to "average" level of their mathematics performance. Significant differences existed in their pretest scores and posttest scores of the students in creativity and mathematics performance in both groups. At the end of the intervention, the students were able to exhibit and show characteristics of having a growth mindset by having the drive to achieve the goals, a positive outlook and love for challenges, the confidence to communicate and to work in group, the need to constantly improve oneself, be self-regulated and learn from the mistakes made. Significance: This study may give contribution and benefit to policy makers and teachers to address the perennial problem regarding the negative attitude and mindset of the students towards mathematics which results to poor performance in mathematics and hinders them to achieve academic success in school and for teachers to be creative in designing programs and activities that will best suit the needs of their learners.