Chitosan (CS)/Hydroxyapatite (HA)/Tricalcium Phosphate (ß-TCP)-Based Composites as a Potential Material for Pulp Tissue Regeneration.

This research focused on developing new materials for endodontic treatments to restore tissues affected by infectious or inflammatory processes. Three materials were studied, namely tricalcium phosphate ß-hydroxyapatite (ß-TCP), commercial and natural hydroxyapatite (HA), and chitosan (CS), in different proportions. The chemical characterization using infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the composition of the composite. Scanning electron microscopy (SEM) demonstrated that the design and origin of the HA, whether natural or commercial, did not affect the morphology of the composites. In vitro studies using Artemia salina (A. salina) indicated that all three experimental materials were biocompatible after 24 h, with no significant differences in mortality rate observed among the groups. The subdermal implantation of the materials in block form exhibited biocompatibility and biodegradability after 30 and 60 days, with the larger particles undergoing fragmentation and connective tissue formation consisting of collagen type III fibers, blood vessels, and inflammatory cells. The implanted material continued to undergo resorption during this process. The results obtained in this research contribute to developing endodontic technologies for tissue recovery and regeneration.

Evaluation of the Survival of Lactobacillus fermentum K73 during the Production of High-Oleic Palm Oil Macroemulsion Powders Using Rotor-Stator Homogenizer and Spray-Drying Technique.

This study aimed to evaluate the survival of the probiotic Lactobacillus fermentum when it is encapsulated in powdered macroemulsions to develop a probiotic product with low water activity. For this purpose, the effect of the rotational speed of the rotor-stator and the spray-drying process was assessed on the microorganism survival and physical properties of probiotic high-oleic palm oil (HOPO) emulsions and powders. Two Box-Behnken experimental designs were carried out: in the first one, for the effect of the macro emulsification process, the numerical factors were the amount of HOPO, the velocity of the rotor-stator, and time, while the factors for the second one, the drying process, were the amount of HOPO, inoculum, and the inlet temperature. It was found that the droplet size (ADS) and polydispersity index (PdI) were influenced by HOPO concentration and time, ζ-potential by HOPO concentration and velocity, and creaming index (CI) by speed and time of homogenization. Additionally, HOPO concentration affected bacterial survival; the viability was between 78-99% after emulsion preparation and 83-107% after seven days. The spray-drying process showed a similar viable cell count before and after the drying process, a reduction between 0.04 and 0.8 Log10 CFUg-1; the moisture varied between 2.4% and 3.7%, values highly acceptable for probiotic products. We concluded that encapsulation of L. fermentum in powdered macroemulsions at the conditions studied is effective in obtaining a functional food from HOPO with optimal physical and probiotic properties according to national legislation (>106 CFU mL-1 or g-1).

Comparative analyses of transcriptional responses of Dectes texanus LeConte (Coleoptera: Cerambycidae) larvae fed on three different host plants and artificial diet.

Dectes texanus is an important coleopteran pest of soybeans and cultivated sunflowers in the Midwestern United States that causes yield losses by girdling stems of their host plants. Although sunflower and giant ragweed are primary hosts of D. texanus, they began colonizing soybeans approximately 50 years ago and no reliable management method has been established to prevent or reduce losses by this pest. To identify genes putatively involved when feeding soybean, we compared gene expression of D. texanus third-instar larvae fed soybean to those fed sunflower, giant ragweed, or artificial diet. Dectes texanus larvae differentially expressed 514 unigenes when fed on soybean compared to those fed the other diet treatments. Enrichment analyses of gene ontology terms from up-regulated unigenes in soybean-fed larvae compared to those fed both primary hosts highlighted unigenes involved in oxidoreductase and polygalacturonase activities. Cytochrome P450s, carboxylesterases, major facilitator superfamily transporters, lipocalins, apolipoproteins, glycoside hydrolases 1 and 28, and lytic monooxygenases were among the most commonly up-regulated unigenes in soybean-fed larvae compared to those fed their primary hosts. These results suggest that D. texanus larvae differentially expressed unigenes involved in biotransformation of allelochemicals, digestion of plant cell walls and transport of small solutes and lipids when feeding in soybean.

Red LED Light Acts on the Mitochondrial Electron Chain of Donkey Sperm and Its Effects Depend on the Time of Exposure to Light.

This work aimed to investigate how stimulation of donkey sperm with red LED light affects mitochondrial function. For this purpose, freshly diluted donkey semen was stimulated with red light for 1, 5, and 10 min, in the presence or absence of oligomycin A (Omy A), a specific inhibitor of mitochondrial ATP synthase, or FCCP, a specific disruptor of mitochondrial electron chain. The results obtained in the present study indicated that the effects of red LED light on fresh donkey sperm function are related to changes in mitochondria function. In effect, irradiation of donkey sperm resulted in an increase in mitochondrial membrane potential (MMP), the activity of cytochrome C oxidase and the rate of oxygen consumption. In addition, in the absence of oligomycin A and FCCP, light-stimulation augmented the average path velocity (VAP) and modified the structure of motile sperm subpopulations, increasing the fastest and most linear subpopulation. In contrast, the presence of either Omy A or FCCP abolished the aforementioned effects. Interestingly, our results also showed that the effects of red light depend on the exposure time applied, as indicated by the observed differences between irradiation protocols. In conclusion, our results suggest that exposing fresh donkey sperm to red light modulates the function of their mitochondria through affecting the activity of the electron chain. However, the extent of this effect depends on the irradiation pattern and does not exclude the existence of other mechanisms, such as those related to thermotaxis.

Red LED Light Acts on the Mitochondrial Electron Chain of Mammalian Sperm via Light-Time Exposure-Dependent Mechanisms.

This work analyzes the effects of red LED light on mammalian sperm mitochondrial function, using the pig as an animal model. Liquid-stored pig semen was stimulated with red-light for 1, 5 and 10 min in the presence or absence of oligomycin A, a specific inhibitor of mitochondrial ATP synthase, or carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), a specific disruptor of mitochondrial electron chain. Whereas exposure for 1 and 5 min significantly (p < 0.05) decreased total motility and intracellular ATP levels, irradiation for 10 min induced the opposite effect. Oligomycin A abolished the light-effects on intracellular ATP levels, O2 consumption and mitochondrial membrane potential, whereas compared to non-irradiated samples, FCCP significantly (p < 0.05) increased O2 consumption when sperm were irradiated for 1 min. Both oligomycin A and FCCP significantly (p < 0.05) decreased total motility. Red-light increased cytochrome c oxidase activity with a maximal effect after 5 min of irradiation, which was abolished by both oligomycin A and FCCP. In conclusion, red-light modulates sperm mitochondrial function via electron chain activity in an exposition, time-dependent manner.

Medium-term effects of the diluted pig semen irradiation with red LED light on the integrity of nucleoprotein structure and resilience to withstand thermal stress.

This study sought to evaluate the effects of irradiating pig seminal doses with red LED light irradiation on their quality and longevity over liquid-storage at 17 °C. For this purpose, boar ejaculates were diluted in a commercial extender at a final concentration of 3 × 107 sperm/mL and stored at 17 °C for 96 h. Upon arrival to our laboratory (5-6 h within collection), 1.5 mL-aliquots were subjected to irradiation with a temperature-controlled red light-emitting diode (LED) for 1 min, 5 min or 10 min. Controls consisted of non-irradiated spermatozoa. Aliquots were then stored at 17 °C for 96 h, and plasma membrane and acrosome integrity, motility and free cysteine radicals of sperm head proteins were evaluated every 24 h. In addition, the sperm resilience to withstand thermal stress following irradiation was evaluated at 24 h, 48 h, 72 h and 96 h by incubating stored seminal doses at 37 °C for 120 min. In our experimental conditions, light-stimulation for 5 min and 10 min counteracted the decrease in thermal stress observed in non-irradiated samples during the first 48 h of storage. Moreover, all irradiation protocols counteracted the decrease in percentages of spermatozoa with altered acrosomes observed in non-irradiated samples after 72 h of storage. The effects of light-stimulation upon sperm motility parameters were less consistent. While liquid-storage also led to an increase in the free cysteine levels of sperm head proteins, this increment was partially mitigated through light-stimulation for 5 min and 10 min. Our results suggest that effects linked with red LED light irradiation would be consistently maintained in our experimental conditions for the first 48 h. Finally, the maintenance of light effect appears to depend upon the specific experimental design, the analyzed sperm parameters and the utilized irradiation patterns.

Acrylic Bone Cements Modified with Graphene Oxide: Mechanical, Physical, and Antibacterial Properties.

Bacterial infections are a common complication after total joint replacements (TJRs), the treatment of which is usually based on the application of antibiotic-loaded cements; however, owing to the increase in antibiotic-resistant microorganisms, the possibility of studying new antibacterial agents in acrylic bone cements (ABCs) is open. In this study, the antibacterial effect of formulations of ABCs loaded with graphene oxide (GO) between 0 and 0.5 wt.% was evaluated against Gram-positive bacteria: Bacillus cereus and Staphylococcus aureus, and Gram-negative ones: Salmonella enterica and Escherichia coli. It was found that the effect of GO was dependent on the concentration and type of bacteria: GO loadings ≥0.2 wt.% presented total inhibition of Gram-negative bacteria, while GO loadings ≥0.3 wt.% was necessary to achieve the same effect with Gram-positives bacteria. Additionally, the evaluation of some physical and mechanical properties showed that the presence of GO in cement formulations increased wettability by 17%, reduced maximum temperature during polymerization by 19%, increased setting time by 40%, and increased compressive and flexural mechanical properties by up to 17%, all of which are desirable behaviors in ABCs. The formulation of ABC loading with 0.3 wt.% GO showed great potential for use as a bone cement with antibacterial properties.

Comparative transcriptomics of Diuraphis noxia and Schizaphis graminum fed wheat plants containing different aphid-resistance genes.

The molecular bases of aphid virulence to aphid crop plant resistance genes are poorly understood. The Russian wheat aphid, Diuraphis noxia, (Kurdjumov), and the greenbug, Schizaphis graminum (Rondani), are global pest of cereal crops. Each species damages barley, oat, rye and wheat, but S. graminum includes fescue, maize, rice and sorghum in its host range. This study was conducted to compare and contrast the transcriptomes of S. graminum biotype I and D. noxia biotype 1 when each ingested phloem from leaves of varieties of bread wheat, Triticum aestivum L., containing no aphid resistance (Dn0), resistance to D. noxia biotype 1 (Dn4), or resistance to both D. noxia biotype 1 and S. graminum biotype I (Dn7, wheat genotype 94M370). Gene ontology enrichments, k-means analysis and KEGG pathway analysis indicated that 94M370 plants containing the Dn7 D. noxia resistance gene from rye had stronger effects on the global transcriptional profiles of S. graminum and D. noxia relative to those fed Dn4 plants. S. graminum responds to ingestion of phloem sap from 94M370 plants by expression of unigenes coding for proteins involved in DNA and RNA repair, and delayed tissue and structural development. In contrast, D. noxia displays a completely different transcriptome after ingesting phloem sap from Dn4 or 94M370 plants, consisting of unigenes involved primarily in detoxification, nutrient acquisition and structural development. These variations in transcriptional responses of D. noxia and S. graminum suggest that the underlying evolutionary mechanism(s) of virulence in these aphids are likely species specific, even in cases of cross resistance.

Resistance to antiretroviral therapy (ART) in patients with HIV/AIDS after therapeutic failure / Resistencia a la terapia antirretroviral (TAR) en pacientes VIH/SIDA en fracaso terapéutico

Abstract Introduction: HIV replication and the suboptimal use of antiretrovirals are directly related to the appearance of resistant mutations. The objective of this study was to describe the resistance mutations (RMs) present in HIV infected patients who experienced antiretroviral treatment failure between 2002 and 2015 in Cali, Colombia. Method: 403 genotypes of adult patients with HIV/AIDS who received ART and experienced virological failure were analyzed. With informed consent, resistance genotype testing was performed using TRUGENE HIV-1; the RMs were defined according to the International AIDS Society-2015 list. The sample was subdivided by periods (2002-2006 vs 2007-2015) and early versus late genotyping. Mutations with ≥15 points to some ARV were considered, according to the Stanford HIV database. Results: comparing the periods, there were more RMs for non-nucleoside reverse transcriptase inhibitors (NNRTIs) in 2007-2015 than in 2002-2006 (85% vs. 60%, respectively, p<0.0001), but protease inhibitors were less affected in 2007-2015 than in 2002-2006 (11% vs. 29%, respectively, p < 0.001). The M184V and K103 N mutations were the most frequent RMs in reverse transcriptase (RT) for NRTIs and NNRTIs, respectively. A total of 67.5% were early genotypes. There was a higher prevalence of certain RMs in late genotypes compared to early ones, mainly for RMs to PIs (D30N, L90M) and NRTIs (M41L, D67N, K70R, L210W); but a lower prevalence of RMs to NNRTIs (Y181C). Conclusion: the late resistance genotypes were associated with higher levels of resistance mutations, mainly to the NNRTI and NRTI families, limiting their use as a rescue therapy alternative. (Acta Med Colomb 2019; 44. DOI:https://doi.org/10.36104/amc.2019.1546).

Resumen Introducción: la replicación del VIH y la utilización subóptima de antirretrovirales, se relacionan directamente con la aparición de mutaciones de resistencias. el objetivo del estudio fue describir las mutaciones de resistencia (mdr) presentes en pacientes infectados por vih que fracasaron a la terapia antirretroviral entre 2002 y 2015 en cali, colombia. Metodología: se analizaron 403 genotipos de pacientes adultos con VIH/SIDA que recibían TAR y experimentaban fracaso virológico. Bajo consentimiento informado, se llevó a cabo la prueba de genotipo de resistências usando TRUGENE HIV-1, se definieron las MDR según el listado de International AIDS Society-2015. Se subdividió la muestra por periodos (2002-2006 vs 2007-2015) y momento de genotipificación temprano versus tardio. Mutaciones con ≥15 puntos a algún ARV fueron consideradas, según la HIV-database de Stanford. Resultados: comparando los periodos, en 2007-2015 hubo mayor afectación de MDR para los inhibidores no nucleosídicos de la transcriptasa reversa (ITINAN) frente a 2002-2006 (85% vs. 60%, respectivamente, p<0.0001), pero menor afectación en 2007-2015 frente a 2002-2006 para inhibidores de la proteasa (11% vs. 29%, respectivamente p < 0.001). Mutaciones M184V y K103N fueron las MDR más frecuentes en la retrotranscriptasa (RT) para ITIAN e ITINAN, respectivamente. El 67.5% fueron genotipos considerados tempranos. Mayor prevalencia de ciertas MDR cuando el genotipo fue tardío frente al temprano, principalmente para MDR a IP (D30N, L90M), ITIAN (M41L, D67N, K70R, L210W), pero menor para MDR a ITINAN (Y181C). Conclusion: los estudios de genotipo de resistencias realizados tardiamente, se asociaron con mayores niveles de mutaciones que confieren resistencias, principalmente a las familias de ITINAN e ITIAN, limitando su uso como alternativa terapéutica de rescate. (Acta Med Colomb 2019; 44. DOI:https://doi.org/10.36104/amc.2019.1546).

Insights into the behavior of six rationally designed peptides based on Escherichia coli's OmpA at the water-dodecane interface.

The Escherichia coli's membrane protein OmpA has been identified as a potential biosurfactant due to their amphiphilic nature, and their capacity to stabilize emulsions of dodecane in water. In this study, the influence of surfactant type, concentration, preservation time and droplet size on the crystallization of n-dodecane and water, in oil-in-water emulsions stabilized with six rationally designed Escherichia coli's OmpA-based peptides was investigated. A differential scanning calorimetry (DSC) protocol was established using emulsions stabilized with Tween 20® and Tween 80®. A relationship between the surfactant concentration and the crystallization temperatures of n-dodecane and water was observed, where the crystallization temperatures seem to be dependent on the preservation time. A deconvolution analysis shows that the peak morphology possibly depends on the interactions at the interface because the enthalpic contributions of each Gaussian peak remained similar in emulsions stabilized with the same peptide. Adsorption results show that the main driver for adsorption and thus stabilization of emulsions is polar interactions (e.g. H-bonding) through the hydrophilic parts of the peptides. Those peptides with a preponderance of polar interaction groups distribution (i.e. NH2, COOH, imidazole) showed the highest interfacial activity under favorable pH conditions. This suggests that custom-made peptides whose hydrophilic/hydrophobic regions can be fine-tuned depending on the application can be easily produced with the additional advantage of their biodegradable nature.

De novo histoid leprosy in a Colombian patient with multiple skin nodules on the ears and extremities.

Histoid leprosy is an uncommon form of lepromatous leprosy with distinct clinical, histopathological, immunological, and bacteriological features. This variant usually occurs in multibacillary patients who have irregular or inadequate treatment. Herein, we report a case of de novo histoid leprosy diagnosed in a patient from Cali, Colombia. In endemic areas, histoid leprosy should be in the differential diagnosis of any patient presenting with skin nodules. Early diagnosis and appropriate treatment are recommended for mitigating the impact of histoid leprosy cases, which are important reservoirs of Mycobacterium leprae.

De novo histoid leprosy in a Colombian patient with multiple skin nodules on the ears and extremities

Abstract Histoid leprosy is an uncommon form of lepromatous leprosy with distinct clinical, histopathological, immunological, and bacteriological features. This variant usually occurs in multibacillary patients who have irregular or inadequate treatment. Herein, we report a case of de novo histoid leprosy diagnosed in a patient from Cali, Colombia. In endemic areas, histoid leprosy should be in the differential diagnosis of any patient presenting with skin nodules. Early diagnosis and appropriate treatment are recommended for mitigating the impact of histoid leprosy cases, which are important reservoirs of Mycobacterium leprae.

Low level of the immune response against rabies virus in dogs and cats, a cross-sectional study in sheltered animals, Santander, Colombia / Baixo nível de resposta imune contra o vírus da raiva em cães e gatos, um estudo transversal em animais abrigados, Santander, Colombia

Rabies is an incurable and fatal progressive viral encephalomyelitis that causes approximately 61,000 deaths a year globally mainly by dog bites, which show the importance of anti-rabies vaccination in dogs to achieve elimination of the disease. In Colombia, multiple cases of human rabies transmitted by dogs and cats have been reported since 1999, showing an increased significance of cats in the transmission of rabies, mainly in rabies of wild origin. Therefore, the aim of the present study was to evaluate the development of neutralizing antibodies in dogs and cats during the mass vaccination campaign of the second half of 2015 in the city of Bucaramanga. For this purpose, a descriptive cross-sectional study with convenience sampling was conducted in 382 dogs and cats (295 dogs, 87 cats), and an evaluation of the humoral immune response of the animals was performed by quantitative ELISA. The prevalence of optimal neutralizing antibodies (>0.5 IU/ml) was only 32.76% (95% CI=28.05-37.46%) in the entire population studied and most of the animals did not have an adequate response to the vaccination, or seroconversion was not detected on them (65.45-95% confidence interval, CI=60.68-70.21%). Significant difference was found between the neutralizing antibody titers in cats and dogs, with a higher neutralizing response in cats. In conclusion, although mass vaccination campaigns for dogs and cats are the most important measure to interrupt virus circulation among the animals, achievement of a good neutralizing immune response in the animals is useful to demonstrate that vaccination has been successful, allowing the maintenance of the required minimum levels of population immunity. These results will allow the implementation of corrective measures in Bucaramanga to achieve better seroconversion rates. Other cities are expected to implement similar seroconversion assessments to verify the quality of effective anti-rabies vaccination in animal populations.(AU)

A raiva é uma encefalomielite viral progressiva incurável e fatal que causa aproximadamente 61.000 mortes por ano no mundo, principalmente por mordidas de cães, que mostram a importância da vacinação anti-rábica em cães para conseguir a eliminação da doença. Na Colômbia, vários casos de raiva humana transmitida por cães e gatos foram relatados desde 1999, mostrando um aumento na importância de gatos na transmissão da raiva, principalmente em raiva de origem selvagem. Portanto, o objetivo do presente estudo foi avaliar o desenvolvimento de anticorpos neutralizantes em cães e gatos durante a campanha de vacinação em massa do segundo semestre de 2015 na cidade de Bucaramanga. Para este propósito, um estudo descritivo transversal com amostragem de conveniência foi realizado em 382 cães e gatos (295 cães, 87 gatos), e uma avaliação da resposta imune humoral dos animais foi realizada por ELISA quantitativo. A prevalência de anticorpos neutralizantes ótimos (>0,5 UI/ml) foi de apenas 32,76% (IC 95% = 28,05-37,46%) em toda a população estudada e a maioria dos animais não teve resposta adequada à vacinação, ou a soroconversão foi não detectado neles (65,45-95% intervalo de confiança IC = 60,68-70,21%). Diferença significativa foi encontrada entre os títulos de anticorpos neutralizantes em gatos e cães, com uma maior resposta neutralizante em gatos. Em conclusão, embora as campanhas de vacinação em massa para cães e gatos sejam a medida mais importante para interromper a circulação do vírus entre os animais, a obtenção de uma boa resposta imunológica neutralizante nos animais é útil para demonstrar que a vacinação foi bem sucedida, permitindo a manutenção necessária dos níveis mínimos de imunidade da população. Esses resultados permitirão que a implementação de medidas corretivas em Bucaramanga alcance melhores taxas de soroconversão. Outras cidades devem implementar avaliações similares de soroconversão para verificar a qualidade da vacinação anti-rábica efetiva em populações animais.(AU)

Resistencias transmitidas del VIH-1 en pacientes sin exposición previa a terapia antirretroviral (Naïve) Cali-Colombia 2008-2015 / Transmitted HIV-1 resistance in never exposed to antiretroviral therapy patients, Cali-Colombia 2008-2015

Objetivo: Determinar la frecuencia de resistencias transmitidas en pacientes VIH no expuestos a terapia antirretroviral. Metodología: Estudio transversal, entre 2008 y 2015 participaron 342 pacientes mayores de 18 años, con infección VIH-1, sin exposición a antirretrovirales, con genotipo de resistencias previo al inicio con antirretrovirales y consentimiento informado. Se incluyeron mutaciones de resistencias definidas por Organización Mundial de Salud (OMS)-2009 e internacional AIDS Society-USA 2015. Se recolectaron características sociodemográficas y clínicas relacionadas con VIH. Resultados: Edad promedio 32±10,5 años; 74% hombres. Al genotipo, mediana de carga viral 26.802 copias/mL, y 343 células T-CD4/mm3 . Según lista de Organización Mundial de Salud-2009 la frecuencia de mutaciones fue 3.2% y considerando mutaciones de internacional AIDS Society y base de datos VIH-Stanford, esta fue 7.9%. Mutaciones más comunes: K103N/S (2.1%), Q58E (2%), V108I y E138A (1.2%). Mutaciones en transcriptasa reversa 4.4% para inhibidores no nucleosídicos y 1.2% para nucleosídicos; para inhibidores de proteasa 2.3%. En pacientes con probable infección retroviral <1 año, la prevalencia de resistencias transmitidas, según la lista de OMS-2009, fue 7.3%, mientras que, con infección ≥1 año fue 1.6% (p=0.008). Conclusión: En pacientes con probable infección <1 año, la frecuencia de mutaciones transmitidas superó el umbral recomendado por la Organización Mundial de Salud para implementar genotipo de resistencias.

Introduction: This study determined the frequency of transmitted drug resistance in patients not exposed to ART, attended in Cali-Colombia. Methodology: A cross-sectional study between 2008 and 2015 involved 342 patients older than 18 years, with confirmed HIV infection, without exposure to antiretrovirals, with resistance genotype prior to initiation of antiretroviral and informed consent. Resistance mutations defined by WHO-2009 and international AIDS Society-USA 2015 were included. Sociodemographic and clinical characteristics related to HIV were also collected. Results: The mean age was 32 ± 10.5 years; 74% were men. At the time of genotype, median viral load was 26,802 copies / mL, and 343 T-CD4 / mm3 cells. According to the WHO-2009 list, the frequency of mutations was 3.2% and considering the AIDS Society-USA list and the Stanford HIV database mutations, this reached 7.9%. The most common mutations were K103N/S (2.1%), Q58E (2%), V108I and E138A (1.2%). Reverse transcriptase mutations were found in 4.4% for non-nucleoside inhibitors and 1.2% for nucleoside; for protease inhibitors were 2.3%. In patients with retroviral infection <1 year, the transmitted resistances prevalence, using only the WHO-2009 list, reach 7.3%, while in those with ≥1 year only was 1.6% (p=0.008). Conclusions: The frequency of transmitted mutations in naïve patients with retroviral infection <1 year exceeded the prevalence threshold recommended by the WHO to implement the resistance genotype.

Monitoring and reporting attacks on education in the Democratic Republic of the Congo and Somalia.

The United Nations' Monitoring and Reporting Mechanism is charged with documenting six grave violations against children in a time of conflict, including attacks on schools. Many of these incidents, however, remain unreported across the globe. This study explores whether or not a local knowledge base of education and child protection actors in North and South Kivu Provinces, Democratic Republic of the Congo, and in Mogadishu, Somalia, could contribute to a more complete record of attacks on education in those areas. Hundreds of semi-structured interviews were conducted with key informants across the three settings, and in total 432 attacks on education were documented. Purposive samples of these reports were verified and a large majority was confirmed. Local non-governmental organisations and education institutions were most knowledgeable about these incidents, but most never reported them to a monitoring authority. The study concludes that attack surveillance and response were largely insufficient, and recommends investing in mechanisms that utilise local knowledge to address these shortcomings.

Construyendo el concepto de la resiliencia: una revisión de la literatura / Building the concept of resilience: a review of the literature

Este articulo expone una revisión bibliográfica de la resiliencia como proceso transformador que se ha venido consolidando a través del tiempo y que surge a partir de la psicología positiva. Ofrece, además, algunas reflexiones finales para clarificar el concepto de resiliencia, pese a sus múltiples usos e interpretaciones, a partir del lente del sociólogo Stefan Vanistendael, quién brinda una comprensión más holística e integral de su significado.

This article exposes a bibliographic review of resilience as a transformative process that has been consolidated over time and that arises from positive psychology. It also offers some final reflections to clarify the concept of resilience, despite its multiple uses and interpretations, from the lens of sociologist Stefan Vanistendael, who provides a more holistic and comprehensive understanding of its meaning.

Resistance of Select Winter Wheat (Triticum aestivum) Cultivars to Rhopalosiphum padi (Hemiptera: Aphididae).

The bird cherry-oat aphid (Rhopalosiphum padi L.) is a global pest of wheat and vectors some of the most damaging strains of barley yellow dwarf virus (BYDV). In years of heavy R. padi infestation, R. padi and BYDV together reduce wheat yields by 30-40% in Kansas and other states of the U.S. Great Plains wheat production area. Cultivation of wheat cultivars resistant to R. padi can greatly reduce production costs and mitigate R. padi-BYDV yield losses, and increase producer profits. This study identified cultivars of hard red and soft white winter wheat with R. padi resistance that suppress R. padi populations or tolerate the effects of R. padi feeding damage. 'Pioneer (S) 25R40,' 'MFA (S) 2248,' 'Pioneer (S) 25R77,' and 'Limagrain LCS Mint' significantly reduced R. padi populations. MFA (S) 2248, Pioneer (S) 25R40, and 'Limagrain LS Wizard' exhibited tolerance expressed as significantly greater aboveground biomass. These findings are significant in that they have identified wheat cultivars currently available to producers, enabling the immediate improvement of tactics to manage R. padi and BYDV in heavily infested areas. Secondarily, these results identify cultivars that are good candidates for use in breeding and genetic analyses of arthropod resistance genes in wheat.

Wheat Genotypes With Combined Resistance to Wheat Curl Mite, Wheat Streak Mosaic Virus, Wheat Mosaic Virus, and Triticum Mosaic Virus.

The wheat curl mite, Aceria tosichella Keifer, (WCM) is a global pest of bread wheat that reduces yields significantly. In addition, WCM carries Wheat streak mosaic virus (WSMV, family Potyviridae, genus Tritimovirus), the most significant wheat virus in North America; High Plains wheat mosaic virus (HPWMoV, genus Emaravirus, formerly High plains virus); and Triticum mosaic virus (TriMV, family Potyviridae, genus Poacevirus). Viruses carried by WCM have reduced wheat yields throughout the U.S. Great Plains for >50 yr, with average yield losses of 2-3% and occasional yield losses of 7-10%. Acaricides are ineffective against WCM, and delayed planting of winter wheat is not feasible. Five wheat breeding lines containing Cmc4, a WCM resistance gene from Aegilops tauschii, and Wsm2, a WSMV resistance gene from wheat germplasm CO960293-2 were selected from the breeding process and assessed for phenotypic reaction to WCM feeding, population increase, and the degree of WSMV, HPWMoV, and TriMV infection. Experiments determined that all five lines are resistant to WCM biotype 1 feeding and population increase, and that two breeding lines contain resistance to WSMV, HPWMoV, and TriMV infection as well. These WCM-, WSMV-, HPWMoV-, and TriMV-resistant genotypes can be used improve management of wheat yield losses from WCM-virus complexes.