Earthworm and arbuscular mycorrhizal communities in agricultural soils : management of key soil organisms for sustainable agriculture

Intensive agriculture is detrimental to soil biodiversity and functioning. Promoting communities of key soil organisms, such as earthworms and arbuscular mycorrhizal (AM) fungi, may help improve agricultural sustainability by replacing inputs with ecosystem services. In this thesis, I explore ways to manage earthworm communities for improved soil functioning via adjusted agricultural practices, promotion of source habitats in the landscape, and inoculation. I also explore the effects of soil compaction on AM fungal symbiosis in wheat varieties, and test application of grassland soil as a method to increase AM fungal diversity in agricultural soils. I show that diverse earthworm communities and bioturbation can be promoted by reducing tillage intensity and total earthworm densities can be increased via diversifying crop rotations. Moist and fertile semi-natural grasslands with high small-scale habitat heterogeneity may serve to sustain earthworm diversity in agricultural landscapes. Inoculation with commercially obtained Lumbricus terrestris earthworms may help restore populations of this tillage sensitive species and improve wheat growth but the long-term establishment of these worms is uncertain. Application of grassland soil may increase AM fungal diversity in agricultural soils but this may not be reflected in AM fungal taxa colonizing wheat roots. I also show that soil compaction differently affects AM colonization in wheat varieties. Further research needs to identify which earthworm and AM fungal community properties best result in functional benefits under different conditions. Nevertheless, I show that earthworm and AM fungal communities can be promoted in various ways, individually or in combination, suggesting potential to enhance functional effects of these key organisms in agricultural soils

Lightcurve inversion for asteroid spins and shapes

Knowledge of the physical properties of asteroids is crucial in many branches of solar-system research. Knowledge of the spin states and shapes is needed, e.g., for accurate orbit determination and to study the history and evolution of the asteroids. In my thesis, I present new methods for using photometric lightcurves of asteroids in the determination of their spin states and shapes. The convex inversion method makes use of a general polyhedron shape model and provides us at best with an unambiguous spin solution and a convex shape solution that reproduces the main features of the original shape. Deriving information about the non-convex shape features is, in principle, also possible, but usually requires a priori information about the object. Alternatively, a distribution of non-convex solutions, describing the scale of the non-convexities, is also possible to be obtained. Due to insufficient number of absolute observations and inaccurately defined asteroid phase curves, the $c/b$-ratio, i.e., the flatness of the shape model is often somewhat ill-defined. However, especially in the case of elongated objects, the flatness seems to be quite well constrained, even in the case when only relative lightcurves are available. The results prove that it is, contrary to the earlier misbelief, possible to derive shape information from the lightcurve data if a sufficiently wide range of observing geometries is covered by the observations. Along with the more accurate shape models, also the rotational states, i.e., spin vectors and rotation periods, are defined with improved accuracy. The shape solutions obtained so far reveal a population of irregular objects whose most descriptive shape characteristics, however, can be expressed with only a few parameters. Preliminary statistical analyses for the shapes suggests that there are correlations between shape and other physical properties, such as the size, rotation period and taxonomic type of the asteroids. More shape data of, especially, the smallest and largest asteroids, as well as the fast and slow rotators is called for in order to be able to study the statistics more thoroughly.Olemme osoittaneet että, vastoin aiempaa käsitystä, asteroidien kirkkausvaihtelun avulla on mahdollista saada kappaleiden muodosta enemmän tietoa kuin vain ylimalkaiset mittasuhteet. Kehittämämme konveksin muotomallin avulla saadaan esille merkittävimmät muodon epäsäännöllisyydet ja jopa vihjeitä suurten kraattereiden ja muiden painaumien esiintymisestä. Myös pyörähdystila, eli pyörähdysakseli ja -nopeus, saadaan paremman muotomallin myötä ratkaistua tarkemmin. Havaintoaineisto muodostuu ns. valokäyristä, eli perättäisistä asteroidin kirkkaushavainnoista, joista näkyy kappaleen pyörimisestä johtuva kirkkauden vaihtelu. Asteroidien fysikaalisten ominaisuuksien, kuten pyörähdystilan ja muodon, tunteminen on sekä mielenkiintoista että tärkeää. Yksittäisen asteroidin muoto tulee tuntea, jotta saadaan määrättyä tarkkaan sen rata; erityisesti niiden kappaleiden tapauksessa, joiden rata sivuaa Maan rataa, meitä kiinnostavat tarkat törmäystodennäköisyydet. Suunniteltaessa luotainlentoja asteroideille, on kohteen muoto ja pyörähdystila hyödyllistä tuntea, jotta voidaan valmistella lähestyminen mahdollisimman pitkälle etukäteen. Käytännön hyödyn lisäksi asteroidien fysikaalisten ominaisuuksien tunteminen on oiva työkalu, kun etsimme tietoa aurinkokuntamme synnystä ja kehityksestä. Tähän tarvitaan yksittäisen kappaleen ominaisuuksien lisäksi tilastollista tulkintaa. Alustavat tilastolliset tutkimukset osoittavat, että ominaisuudet ovat jossain määrin riippuvaisia toisistaan ja antavat aiheen perinpohjaisempaan analyysiin, kun muoto- ja pyörähdystila-aineistoa on riittävän suurelle määrälle kohteita. Tulevaisuuden tehokkaat taivaankartoitusohjelmat tulevat tuottamaan runsaasti havaintoaineistoa asteroideille, mahdollistaen muotojen ja pyörähdystilojen määrittämisen arviolta tuhansille kappaleille. Tilastollisen tutkimuksen tulokset paljastavat, miten kappaleiden ominaisuudet ovat riippuvaisia toisistaan ja antavat viitteitä siitä, mitkä mekanismit ovat muokanneet (tai yhä muokkaavat) asteroidien fysikaalisia ominaisuuksia

A CAD/CAM/CNC Curriculum for High School Students

The need for CAD/CAM/CNC curriculum for Washington State was researched. Based on research a resource workbook for CAD/CAM/CNC was in demand. In order to meet the demand for CAD/CAM/CNC curriculum and bridge the gap between the state standards, drafting frameworks, STEM curriculum, increased focus on implementation within multiple disciplines, providing a starting point for teachers who want to use CNC machinery in their program, and prepare students for quality jobs and careers related to CAD/CAM/CNC, a workbook was created. The workbook includes 27 hands-on lessons and projects, student handouts, applied STEM problems and activities, tutorials, drafting standards, state math standards, and equation sheets. The workbook is designed to be used as a resource for CAD/CAM/CNC teachers in Washington State

The development of cortical processing of speech differs between children with cochlear implants and normal hearing and changes with parental singing

Objective: The aim of the present study was to investigate speech processing development in children with normal hearing (NH) and cochlear implants (CI) groups using a multifeature event-related potential (ERP) paradigm. Singing is associated to enhanced attention and speech perception. Therefore, its connection to ERPs was investigated in the CI group. Methods: The paradigm included five change types in a pseudoword: two easy- (duration, gap) and three difficult-to-detect (vowel, pitch, intensity) with CIs. The positive mismatch responses (pMMR), mismatch negativity (MMN), P3a and late differentiating negativity (LDN) responses of preschoolers (below 6 years 9 months) and schoolchildren (above 6 years 9 months) with NH or CIs at two time points (T1, T2) were investigated with Linear Mixed Modeling (LMM). For the CI group, the association of singing at home and ERP development was modeled with LMM. Results: Overall, responses elicited by the easy- and difficult to detect changes differed between the CI and NH groups. Compared to the NH group, the CI group had smaller MMNs to vowel duration changes and gaps, larger P3a responses to gaps, and larger pMMRs and smaller LDNs to vowel identity changes. Preschoolers had smaller P3a responses and larger LDNs to gaps, and larger pMMRs to vowel identity changes than schoolchildren. In addition, the pMMRs to gaps increased from T1 to T2 in preschoolers. More parental singing in the CI group was associated with increasing pMMR and less parental singing with decreasing P3a amplitudes from T1 to T2. Conclusion: The multifeature paradigm is suitable for assessing cortical speech processing development in children. In children with CIs, cortical discrimination is often reflected in pMMR and P3a responses, and in MMN and LDN responses in children with NH. Moreover, the cortical speech discrimination of children with CIs develops late, and over time and age, their Frontiers in Neuroscience 01 frontiersin.org Torppa et al. 10.3389/fnins.2022.976767 speech sound change processing changes as does the processing of children with NH. Importantly, multisensory activities such as parental singing can lead to improvement in the discrimination and attention shifting toward speech changes in children with CIs. These novel results should be taken into account in future research and rehabilitation.Peer reviewe

Screen Time of Preschool-Aged Children and Their Mothers, and Children’s Language Development

Although children’s increased screen time has been found to associate with poorer language development, it is open to question which part of language ability screen time specifically associates with. Our aim was to examine the association between children’s screen time (alone and together with a parent), mothers’ screen time, and the different domains of children’s language skills. Mothers reported their children’s (N = 164, aged 2.5 to 4.1 years) screen time and their own on a weekday and a day off. Children’s lexical, phonological, morphological, receptive, and general language abilities were measured using validated tests. The connections between children’s and mothers’ screen time and children’s language skills were analyzed using correlation analyses and linear regression models. The more the children used screen time alone, or the greater the amount of the mothers’ screen time, the weaker the children’s lexical and general language abilities when the children’s age, maternal education level, and birth order were controlled for. We also found cumulative, negative links to the children’s lexical and general language abilities when the amount of their screen time alone and the amount of the mothers’ screen time were simultaneously included in the regression model. The results suggest that it is important to restrict both children’s screen time spent alone and mothers’ screen time

An Examination of the Impact of Organizational Restructuring on Identification Within Extension

Many Extension organizations enjoy strong Organizational Identification (OI) among personnel. But organizational change may negatively influence identification, and many Extension organizations have been changing the way they serve their publics. To examine the impact of change on OI, we compared Extension personnel\u27s OI scores following a major restructuring to OI scores gathered during a period of relative stability reported in previous research from another Extension organization. Findings indicated that OI scores were slightly lower following restructuring; however, the pattern of scores across four targets (Extension, program area, counties, and centers) remained constant, suggesting personnel will rarely identify with mid-level targets

The development of cortical processing of speech differs between children with cochlear implants and normal hearing and changes with parental singing

Objective: The aim of the present study was to investigate speech processing development in children with normal hearing (NH) and cochlear implants (CI) groups using a multifeature event-related potential (ERP) paradigm. Singing is associated to enhanced attention and speech perception. Therefore, its connection to ERPs was investigated in the CI group. Methods: The paradigm included five change types in a pseudoword: two easy- (duration, gap) and three difficult-to-detect (vowel, pitch, intensity) with CIs. The positive mismatch responses (pMMR), mismatch negativity (MMN), P3a and late differentiating negativity (LDN) responses of preschoolers (below 6 years 9 months) and schoolchildren (above 6 years 9 months) with NH or CIs at two time points (T1, T2) were investigated with Linear Mixed Modeling (LMM). For the CI group, the association of singing at home and ERP development was modeled with LMM. Results: Overall, responses elicited by the easy- and difficult to detect changes differed between the CI and NH groups. Compared to the NH group, the CI group had smaller MMNs to vowel duration changes and gaps, larger P3a responses to gaps, and larger pMMRs and smaller LDNs to vowel identity changes. Preschoolers had smaller P3a responses and larger LDNs to gaps, and larger pMMRs to vowel identity changes than schoolchildren. In addition, the pMMRs to gaps increased from T1 to T2 in preschoolers. More parental singing in the CI group was associated with increasing pMMR and less parental singing with decreasing P3a amplitudes from T1 to T2. Conclusion: The multifeature paradigm is suitable for assessing cortical speech processing development in children. In children with CIs, cortical discrimination is often reflected in pMMR and P3a responses, and in MMN and LDN responses in children with NH. Moreover, the cortical speech discrimination of children with CIs develops late, and over time and age, their Frontiers in Neuroscience 01 frontiersin.org Torppa et al. 10.3389/fnins.2022.976767 speech sound change processing changes as does the processing of children with NH. Importantly, multisensory activities such as parental singing can lead to improvement in the discrimination and attention shifting toward speech changes in children with CIs. These novel results should be taken into account in future research and rehabilitation.Peer reviewe

Pitch-related auditory skills in children with cochlear implants : The role of auditory working memory, attention and music

The cochlear implant (CI) provides a sensation of hearing for deaf-born children. However, many CI children show poor language outcomes, which may be related to the deficiency of CIs in delivering pitch. This thesis studies the development of those neural processes and behavioural skills linked to the perception of pitch which may play a role in language acquisition. We measured with event-related brain potentials (ERPs) the neural discrimination of and attention shift to changes in music, the perception of word and sentence stress and related acoustic cues, and the auditory working memory (forward digit span) in 4̶ 13-year-old normally hearing (NH) and early-implanted children. We studied how the development of these aspects is related to musical activities known to advance brain development and perceptual skills in the NH population, and whether the perception of music is connected to word stress or visuospatial perception in NH adults. With regard to the development of neural responses, we found for the CI children usually well-formed ERP waveforms resembling those found for the NH children. However, some brain responses implied impoverished processing for the CI children, especially for timbre and pitch. The CI children who sang regularly at home were advantaged over the other CI children for the development of attention shift, which was linked to improved auditory working memory, implying better neural discrimination, an advantaged development of neural networks for attention and better updating of auditory working memory for the CI singers. For the CI children perception of word and sentence stress improved with improving discrimination of pitch (f0) and intensity and auditory working memory. Only the CI children participating in supervised musical activities performed and developed similarly to the NH children in these skills. The perception of musical rhythm improved with improving word stress and visuospatial perception for the NH adults. The results indicate that (i) perception of music and speech are connected not only via pitch and timbre, but also via rhythm, and (ii) the combination of singing at home and taking part in supervised musical activities, using also rhythmic exercises and visual cues, might be the best way to optimize pitch-related abilities, underlying cognitive functions, spoken language skills and quality of life for early-implanted children.Sisäkorvaistutteella (SI) kuulevien, kuurona syntyneiden lasten puhekielen taidot vaihtelevat paljon ja ovat usein heikompia kuin kuulevilla lapsilla. Tämä saattaa liittyä SI:n heikkoon kykyyn välittää äänten korkeuksia. Tässä väitöskirjassa tarkasteltiin puhekielen kehitystä tukevien, äänen korkeuksien havaitsemiseen liittyvien hermostollisten mekanismien, kuulomuistin ja kuuntelutaitojen kehitystä 4 13-vuotiailla kuulevilla ja SI-lapsilla. Musiikillisten äänten hermostollista erottelua ja kuulotarkkaavuutta tarkasteltiin mittaamalla kuuloherätevasteita aivosähkökäyrällä (EEG). Sana- ja lausepainon havaitsemista ja näihin liittyvien akustisten vihjeiden erottelukykyä tutkittiin kuuntelukokeilla ja kuulomuistia numerotoistotestillä. Musiikin harrastamisen tiedetään parantavan kuulevien lasten kuulohavaintotaitoja, kuulomuistia ja kuulotarkkaavuutta. Siksi tarkastelimme SI-lasten ryhmässä musiikkiaktiviteettien yhteyksiä mittaustuloksiimme. Tutkimme myös, onko musiikin havaitseminen yhteydessä sanapainon ja suuntien havaitsemiseen kuulevilla aikuisilla. SI-lasten kuuloherätevasteet olivat samantapaisia kuin kuulevien lasten, mutta vasteet erityisesti muutoksille musiikillisten äänten laadussa ja korkeudessa heijastivat SI-lasten heikkoa kuuloerottelukykyä ja -tarkkaavuutta. Säännöllisesti kotona laulavien SI-lasten kuulotarkkaavuusvasteet kehittyivät voimakkaammiksi ja nopeammiksi kuin muiden SI-lasten. Nämä vasteet olivat nopeampia paremman kuulomuistin myötä. Tulokset viittaavat laulavien SI-lasten hyvään hermostolliseen erottelukykyyn, kuulotarkkaavuuden aivoverkostojen kehitykseen ja kuulomuistin päivitykseen. Sana- ja lausepainon havaitseminen parantui hyvän äänen korkeuden (f0) ja voimakkuuden erottelun sekä kuulomuistin myötä, joissa vain ohjattuihin musiikkiaktiviteetteihin osallistuneet SI-lapset kehittyivät yhtä hyvin kuin kuulevat lapset. Musiikin rytmien havaitseminen parantui hyvän sanapainon ja suuntien havaitsemisen myötä. Tulokset korostavat musiikin havaitsemisen olevan yhteydessä musiikin rytmien havaitsemiseen, ei pelkästään äänen korkeuksien ja laatujen havaitsemiseen. Ne korostavat kotona laulamisen sekä äänen korkeuden, myös rytmin havaitsemisen harjoituksia ja suuntavihjeitä (kuten laululeikkejä), sisältävän ohjatun musiikkitoiminnan tärkeyttä SI lasten puhekielen ja elämänlaadun parantamisessa

Pitch- and language related skills: from theory to rehabilitation of hearing-impaired children

Peer reviewe

Acquisition of focus by normal hearing and Cochlear implanted children : The role of musical experience

Two experiments investigated the perception of compound vs. phrasal stress and narrow focus in normally hearing children and children with Cochlear Implants (CI). Additionally, we investigated whether musical experience would predict children’s performance in these tasks. The results showed no difference between CI and normal-hearing (NH) children in either experiment. However, whereas we found no clear effect of age in the children’s stress detection, there was a clear age related trajectory in the ability to recognise (narrow) focus. Moreover, this trend was similar to what has been found previously for English children. Importantly, prior music experience was significantly linked to CI children’s perception of focus.Peer reviewe