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Abstract The evolutionary expansion of sensory neuron populations detecting important environmental cues is widespread, but functionally enigmatic. We investigated this phenomenon through comparison of homologous olfactory pathways of Drosophila melanogaster and its close relative Drosophila sechellia, an extreme specialist for Morinda citrifolia noni fruit. D. sechellia has evolved species-specific expansions in select, noni-detecting olfactory sensory neuron (OSN) populations, through multigenic changes. Activation and inhibition of defined proportions of neurons demonstrate that OSN number increases contribute to stronger, more persistent, noni-odour tracking behaviour. These expansions result in increased synaptic connections of sensory neurons with their projection neuron (PN) partners, which are conserved in number between species. Surprisingly, having more OSNs does not lead to greater odour-evoked PN sensitivity or reliability. Rather, pathways with increased sensory pooling exhibit reduced PN adaptation, likely through weakened lateral inhibition. Our work reveals an unexpected functional impact of sensory neuron population expansions to explain ecologically-relevant, species-specific behaviour.

Abstract Chemosensory tissues exhibit significant between-species variability, yet the evolution of gene expression and cell types underlying this diversity remain poorly understood. To address these questions, we conducted transcriptomic analyses of five chemosensory tissues from six Drosophila species and integrated the findings with single-cell datasets. While stabilizing selection predominantly shapes chemosensory transcriptomes, thousands of genes in each tissue have evolved expression differences. Genes that have changed expression in one tissue have often changed in multiple other tissues but at different past epochs and are more likely to be cell type-specific than unchanged genes. Notably, chemosensory-related genes have undergone widespread expression changes, with numerous species-specific gains/losses including novel chemoreceptors expression patterns. Sex differences are also pervasive, including a D. melanogaster-specific excess of male-biased expression in sensory and muscle cells in its forelegs. Together, our analyses provide new insights for understanding evolutionary changes in chemosensory tissues at both global and individual gene levels.

Abstract Background of this research is suspension packaging: fragile goods are attached to a panel of cardboard by wrapping it in stretch film. The panel is then appropriately folded, and the whole thing is placed in a cardboard box of corresponding dimensions. The primary objective of this study is to identify paper types that might be used in future as a more sustainable alternative for stretch wrap film. The experimental methods that are utilized are basically variants of mechanical pulling tests on paper samples. Sample preparation and sample size are adopted from international standards, but displacement control is adopted to detect relevant stretchability properties. Some kraft papers show a high ultimate tensile stress and a moderate stretchability, mainly permanent stretch as expected. Although the ultimate tensile stress of paper from recycled fibers is lower, some of these paper grades show a considerable higher stretchability including a higher elastic stretch. It is concluded that both kraft paper and paper grades from recycled fibers may be applicable as a wrapping material for suspension packaging. Further experimental research is needed to identify appropriate wrapping parameters for each paper type.

The conventional supply chain of consumer goods uses corrugated boxes on pallets as the main principle for manipulation, storage and transport of the goods. Apart from dimensions the vertical compression strength is the most important selection criterion for the boxes. In the early days of e-commerce corrugated boxes have been adopted as parcel packaging. However in e-commerce boxes are manipulated individually. They are dropped, thrown, rotated, compressed in all directions, … although they are designed for vertical compression resistance. Additional packaging material is required especially in case of fragile goods. Different types of cushioning materials are being used. Often 5 cm of expandable polystyrene chips on all sides around a fragile product is recommended by couriers and insurance companies. Some types of these chips are recyclable but most types fragment easily in small parts that survive for thousands of years if released in nature. In this research an alternative cushioning method is proposed and compared to the polystyrene chips in terms of shock absorption. Five variants of the new method are studied. The cheapest variant turns out to be the best shock absorber as well. Moreover this variant can easily be produced fully automatically. Therefore the new method is considered extremely promising.

Para dar solución al problema de posicionamiento en interiores, muchos autores han propuesto el uso de diversas técnicas. Desde la simulación de un Sistema de Posicionamiento Global (GPS) a través de antenas Pseudolites, la construcción de campos magnéticos artificiales, el uso de diversos sensores como visión, ultrasonido, unidades de medida inercial, entre otros. Hasta el uso de transmisores y receptores en el rango de la Radio Frecuencia como los presentes en una oficina. Muchos de los sistemas anteriormente mencionados dependen para su correcto funcionamiento de una instalación y configuración de equipos en el lugar de posicionamiento, lo cual puede llevar en ocasiones a costosas implementaciones. Es por esto que para realizar este trabajo hemos propuesto una metodología de posicionamiento en interiores que no requiere de adecuaciones e instalaciones en el lugar de aplicación. La metodología propuesta hace uso de las radio estaciones FM existentes y utiliza algoritmos de Deep Learning como algoritmo de posicionamiento.

Abstract Background Suicide is a serious public health concern. Depression is the main gateway to suicidal behavior. The already established relationship between depression and suicidal risk should now focus on the investigation of more specific factors: recent studies have suggested an association between vulnerability to suicidal behavior and neurocognitive alterations, a nuclear symptom of depression. This project aims to identify alterations in the Executive Functions (EF) of patients suffering a first depressive episode that might constitute a risk factor for suicidal ideation, suicidal attempts and suicide, to allow for more adequate suicide prevention. Methods Prospective longitudinal design involving two groups (first depressive episodes with and without alterations in their EF) and four repeated measures (0, 6, 12 and 24 months). The estimated minimum sample size is 216 subjects. The variables and measurement instruments will include socio-demographic variables, clinical variables (age of illness onset, family and personal antecedents, psychopathological and medical comorbidity, suicidal ideation, suicide attempts and completed suicides, severity of depression, including melancholic or atypical, remission of the depressive episode), and neuropsychological variables (EF and decision-making processes evaluated through the Cambridge Neuropsychological Test Automated Battery (CANTAB)). Discussion First and foremost, the identification of clinical and neuropsychological risk factors associated with suicidal behavior will open the possibility to prevent such behavior in patients with a first depressive episode in the context of clinical practice. Secondly, interventions aimed at cognitive impairment (in particular: EF) derived from the study may be incorporated into strategies for the prevention of suicidal behavior. Finally, impaired neurocognitive function (even in early stages) could become an identifiable endophenotype or “marker” in clinical and neurobiological studies about suicidal behavior in depressive patients.

Fruit flies gain valuable information about their environment by sensing chemicals. Here, Arguello et al. show strong signals of recent selection on the chemosensory system of the fruit fly Drosophila melanogaster, consistent with the adaptation of populations to their local chemical environment.

Abstract All of us have marveled at the remarkable diversity of animal behaviors in nature. None of us has much idea of how these have evolved.

Myrosinase (ß-thioglucosidase glucohydrolase (EC 3.2.3.1)) is a glycoprotein responsible for the hydrolysis of glucosinolates, a group of sulfur-containing secondary metabolites present in Brassicaceae plants. Sulforaphane, a powerful anti-cancer compound, comes from the hydrolysis of glucoraphanin, the main glucosinolate found in broccoli. The aim of this work was to investigate the interaction between broccoli myrosinase and different substrates through molecular modelling. Currently the amino acid sequence and the molecular structure of broccoli myrosinase are unknown. The amino acid sequence was deduced from the nucleotide sequence, which in turn was obtained experimentally. The primary sequence of broccoli myrosinase used for modelling consisted of 548 amino acids. The three-dimensional model was generated by an ab initio/threading method using the crystal structure of 1MYR_A and 1DWF_M of Sinapis alba, 1CBG_A of Trifolium repens L, 3PTK_A of Oryza sativa and 3WQ4_A of Camellia sinensis as templates, employing the I-TASSER server. The interaction with glucoraphanin (GRA), sinigrin (SIN), glucoiberin (GIB) and N- acetylglucosamine (NAG) was investigated through molecular docking. The binding energy of GRA, SIN, GIB and NAG to myrosinase were -3.80; -4.71; -4.77 and -5.55 (Kcal/mol), respectively. The simulations of the interaction between GRA and myrosinase suggested that the residues of the active site responsible for substrate stabilization by hydrogen bonding were Gln207, Gly431, Ser433 and Trp 477. The residue involved in the hydrolysis of the ß-D-thioglucose binding was Tyr352. NAG interacts with the active site, as inhibitor. Our results will allow further studies about molecular mechanisms of broccoli myrosinase.

Cinco híbridos de milho foram avaliados quanto à produtividade de matéria seca, ao valor nutritivo da silagem e à produtividade de leite. Os híbridos avaliados foram AS 32, AG 9090, CD 308, DKB 747 e P 30F87, colhidos em três alturas de corte: 15, 35 e 55 cm. O delineamento experimental foi em blocos casualizados com parcelas subdivididas e três repetições. Para confecção das silagens, utilizaram-se silos experimentais de PVC com 20 cm de diâmetro e 40 cm de altura. A produtividade de leite, por tonelada de silagem (eficiência alimentar) e por hectare, foi estimada pelo modelo Milk2006. A produtividade de forragem ensilável reduziu com o aumento da altura de colheita, com resultados de 14,6; 13,0 e 12,6 t/ha MS para as alturas de colheita de 15 cm, 35 cm e 55 cm, respectivamente. O híbrido de milho e a altura de colheita influenciaram a composição bromatológica das silagens, com exceção do teor de extrato etéreo (EE), que não foi influenciado pela altura de colheita. Ocorreu interação híbrido × altura de colheita para o teor de amido, a digestibilidade in vitro da MS e da fibra em detergente neutro (FDN) e o teor de nutrientes digestíveis totais (NDT). Houve efeito da altura de colheita sobre a eficiência alimentar, cujos valores médios foram de 1.226, 1.291 e 1.393 kg leite/t silagem nas alturas de colheita de 15, 35 e 55 cm, respectivamente. Observou-se também efeito do tipo de híbrido sobre a produtividade de leite e a eficiência alimentar, com melhores valores verificados para o híbrido DKB 747 colhido na altura de 55 cm. Ao elevar a altura de colheita, melhora-se o valor nutritivo da silagem sem prejudicar a produtividade de leite por hectare. O manejo da altura de corte não substitui a escolha de melhores híbridos para produção de silagem de alta qualidade e produtividade.Five corn hybrids were evaluated to the productivity of dry matter, nutritive value of silage and milk yield. The hybrids evaluated were AS 32, AG 9090, CD 308, DKB 747 and P 30F87, harvested at three cutting heights: 15, 35 and 55 cm. The experimental design was a randomized block with split plots and three replicates. Experimental silos of PVC with 20 cm of diameter and 40 cm of height were used. Milk yield per ton of silage (feed efficiency) and milk production per hectare were estimated by using the model Milk2006. The productivity of ensilable forage decreased with increase in height of harvest, with results of 14.6, 13.0 and 12.6 t/ha DM for the cut heights of 15 cm, 35 cm and 55 cm, respectively. Corn hybrid and cut height influenced chemical composition of silage, except for EE, which was not influenced by cut height. There was an interaction hybrid × cut height for the content of starch, in vitro digestibility of DM and of neutral detergent fiber (NDF), and content of total digestible nutrients (TDN). Cut height affected feed efficiency whose average values of 1,226, 1,291 and 1,393 kg milk/t silage at the cut heights of 15, 35 and 55 cm, respectively. It was also observed effect of type of hybrid on milk yield and feed efficiency, with the best values recorded for the hybrid DKB 747 harvested at 55 cm of height. By raising the height of harvest, the nutritional value of silage is improved, with no influence on milk yield per hectare. The management of the height of cut does not replace the choice of better hybrids for production of silage with high quality and productivity.

The evolutionary impact of gene duplication events has been a theme of Drosophila genetics dating back to the Morgan School. While considerable attention has been placed on the genetic novelties that duplicates are capable of introducing, and the role that positive selection plays in their early stages of duplicate evolution, much less attention has been given to the potential consequences of ectopic (non-allelic) gene conversion on these evolutionary processes. In this paper we consider the historical origins of ectopic gene conversion models and present a synthesis of the current Drosophila data in light of several primary questions in the field.

In this work, polymer-drugs conjugates used as drug delivery systems (DDS) are revised attending to their chemical conjugation. Namely, the classification of this type of DDS is based on the conjugation sites of the reactive groups (i.e., via end groups or pendant polymer groups). Advantages and limitations of these types of DDS are discussed through representative examples of polymer-drugs and polymer-proteins conjugates recently developed.

Purpose: This study aims to explore and provide empirical evidence for ways that teachers can simultaneously support students' literary reading and analytic writing through dialogic assessment, an approach to conferencing with writers that foregrounds process and integrates assessment and instruction. Design/methodology/approach: This study uses qualitative research methods of three high school teachers' dialogic assessment sessions with individual students to investigate how these teachers both assessed and taught literary reading moves as they observed and supported the students' writing. An expanded version of Rainey's (2017) scheme for coding literary reading practices was used. Findings: The three teachers varied in the range and extent of literary reading practices they taught and supported. The practices that they most commonly modeled or otherwise supported were making claims, seeking patterns and articulating puzzles. The variation we observed in their literary reading practices may be attributed to institutional characteristics of the teachers' contexts. Research limitations/implications: This study illustrates how the concept of prolepsis can be productively used as a lens through which to understand teachers' instructional choices. Practical implications: The descriptive findings show how individualized coaching of students' writing about literature can also support literary reading. Teachers of English need not worry that they have to choose between teaching writing and teaching reading. Originality/value: This study presents dialogic assessment as a useful way to guide students through the writing process and literary interpretation simultaneously.

The evolution of animal behaviour is poorly understood.sup.1,2. Despite numerous correlations between interspecific divergence in behaviour and nervous system structure and function, demonstrations of the genetic basis of these behavioural differences remain rare.sup.3-5. Here we develop a neurogenetic model, Drosophila sechellia, a species that displays marked differences in behaviour compared to its close cousin Drosophila melanogaster.sup.6,7, which are linked to its extreme specialization on noni fruit (Morinda citrifolia).sup.8-16. Using calcium imaging, we identify olfactory pathways in D. sechellia that detect volatiles emitted by the noni host. Our mutational analysis indicates roles for different olfactory receptors in long- and short-range attraction to noni, and our cross-species allele-transfer experiments demonstrate that the tuning of one of these receptors is important for species-specific host-seeking. We identify the molecular determinants of this functional change, and characterize their evolutionary origin and behavioural importance. We perform circuit tracing in the D. sechellia brain, and find that receptor adaptations are accompanied by increased sensory pooling onto interneurons as well as species-specific central projection patterns. This work reveals an accumulation of molecular, physiological and anatomical traits that are linked to behavioural divergence between species, and defines a model for investigating speciation and the evolution of the nervous system. A neurogenetic model, Drosophila sechellia--a relative of Drosophila melanogaster that has developed an extreme specialization for a single host plant--sheds light on the evolution of interspecific differences in behaviour., Author(s): Thomas O. Auer [sup.1] , Mohammed A. Khallaf [sup.2] , Ana F. Silbering [sup.1] , Giovanna Zappia [sup.1] , Kaitlyn Ellis [sup.3] , Raquel Álvarez-Ocaña [sup.1] , J. Roman [...]