Aromatic l-amino acid decarboxylase : histochemical localization in rat kidney and lack of effect of dietary potassium or sodium loading on enzyme distribution

Utilizing a mono-specific antiserum produced in rabbits to hog kidney aromatic L-amino acid decarboxylase (AADC), the enzyme was localized in rat kidney by immunoperoxidase staining. AADC was located predominantly in the proximal convoluted tubules; there was also weak staining in the distal convoluted tubules and collecting ducts. An increase in dietary potassium or sodium intake produced no change in density or distribution of AADC staining in kidney. An assay of AADC enzyme activity showed no difference in cortex or medulla with chronic potassium loading. A change in distribution or activity of renal AADC does not explain the postulated dopaminergic modulation of renal function that occurs with potassium or sodium loading.

Inhibition of guinea-pig renal [Na + K]-ATPase by normotensive human plasma : effects of a high sodium diet

The effect of plasma taken from normotensive humans, while on a low and high sodium diet, on [Na + K]-ATPase and 3H-ouabain binding was measured in tubules from guinea-pig kidneys. Plasma from the high sodium, compared to the low sodium, diet period: (a) inhibited [Na + K]-ATPase activity; (b) decreased 3H-ouabain affinity for binding sites; (c) increased the number of available 3H-ouabain binding sites; (d) decreased [Na + K]-ATPase turnover (activity/3H-ouabain binding sites). The inhibition of [Na + K]-ATPase suggests an increase in a (possible) natriuretic factor. The decreased affinity of 3H-ouabain binding suggests an endogenous ouabainoid, which may be the natriuretic factor.

The challenges of preparing pre-service teachers to embrace a digital pedagogy

The need for pre-service teachers to be proficient in the use of information and communication technologies (ICT) in the classroom once they graduate is essential, though this process is not a straightforward process (Zhang, 2008) and needs to go beyond pre-service teachers just being able to use ICT. Research suggests that for teachers to successfully use ICT in their classrooms they need to be specifically trained to do so (Markauskaite, 2007; Batane, 2004; Jacobsen, Clifford & Friesen, 2002). Pre-service teachers must also be able to embrace and use new and emerging ICT’s, often referred to as digital technologies, within their pedagogical approaches to teaching and learning. According to UNESCO, these “new technologies require new teacher roles, new pedagogies, and new approaches to teacher training” (2008, p.9). However, new approaches to teacher training have moved very slowly in many areas and preparing pre-service teachers to develop proficiency in embracing a digital pedagogy within their own classrooms can be a challenge for teacher training institutes. This paper reports on a case study of first year education students (N=667) and their experiences during their first semester of pre-service teacher education in a core ICT unit. It will report on the background ICT knowledge and skills that these students bring to the course as well as their expectations of the unit and ICT in their future teaching. The paper will then draw on the research results to identify challenges facing teacher training of pre-service teachers in using digital technologies in their future classrooms.

Adaptive teachers embracing new ways of learning with robotics in Chinese schools

In July 2010, China announced the “National Plan for Medium and Long-term Education Reform and Development(2010-2020)” (PRC 2010). The Plan calls for an education system that: • promotes an integrated development which harnesses everyone’s talent; • combines learning and thinking; unifies knowledge and practice; • allows teachers to teach according to individuals’ needs; and • reforms education quality evaluation and personnel evaluation systems focusing on performance including character, knowledge, ability and other factors. This paper discusses the design and implementation of a Professional Learning Program (PLP) undertaken by 432 primary, middle and high school teachers in China. The aim of this initiative was to develop adaptive expertise in using technology that facilitated innovative science and technology teaching and learning as envisaged by the Chinese Ministry of Education’s (2010-2020) education reforms. Key principles derived from literature about professional learning and scaffolding of learning informed the design of the PLP. The analysis of data revealed that the participants had made substantial progress towards the development of adaptive expertise. This was manifested not only by advances in the participants’ repertoires of Subject Matter Knowledge and Pedagogical Content Knowledge but also in changes to their levels of confidence and identities as teachers. It was found that through time the participants had coalesced into a professional learning community that readily engaged in the sharing, peer review, reuse and adaption, and collaborative design of innovative science and technology learning and assessment activities.

A constitutive model for mechanical response characterization of pumpkin peel and flesh tissues under tensile and compressive loadings

Enhancing quality of food products and reducing volume of waste during mechanical operations of food industry requires a comprehensive knowledge of material response under loadings. While research has focused on mechanical response of food material, the volume of waste after harvesting and during processing stages is still considerably high in both developing and developed countries. This research aims to develop and evaluate a constitutive model of mechanical response of tough skinned vegetables under postharvest and processing operations. The model focuses on both tensile and compressive properties of pumpkin flesh and peel tissues where the behaviours of these tissues vary depending on various factors such as rheological response and cellular structure. Both elastic and plastic response of tissue were considered in the modelling process and finite elasticity combined with pseudo elasticity theory was applied to generate the model. The outcomes were then validated using the published results of experimental work on pumpkin flesh and peel under uniaxial tensile and compression. The constitutive coefficients for peel under tensile test was α = 25.66 and β = −18.48 Mpa and for flesh α = −5.29 and β = 5.27 Mpa. under compression the constitutive coefficients were α = 4.74 and β = −1.71 Mpa for peel and α = 0.76 and β = −1.86 Mpa for flesh samples. Constitutive curves predicted the values of force precisely and close to the experimental values. The curves were fit for whole stress versus strain curve as well as a section of curve up to bio yield point. The modelling outputs had presented good agreement with the empirical values and the constructive curves exhibited a very similar pattern to the experimental curves. The presented constitutive model can be applied next to other agricultural materials under loading in future.

A vibrational spectroscopic study of the borate mineral ezcurrite Na4B10O17·7H2O – Implications for the molecular structure

We have studied the boron containing mineral ezcurrite Na4B10O17·7H2O using electron microscopy and vibrational spectroscopy. Both tetrahedral and trigonal boron units are observed. The nominal resolution of the Raman spectrometer is of the order of 2 cm−1 and as such is sufficient enough to identify separate bands for the stretching bands of the two boron isotopes. The Raman band at 1037 cm−1 is assigned to BO stretching vibration. Raman bands at 1129, 1163, 1193 cm−1 are attributed to BO stretching vibration of the tetrahedral units. The Raman band at 947 cm−1 is attributed to the antisymmetric stretching modes of tetrahedral boron. The sharp Raman peak at 1037 cm−1 is from the 11-B component such a mode, then it should have a smaller 10-B satellite near (1.03) × (1037) = 1048 cm−1, and indeed a small peak at 1048 is observed. The broad Raman bands at 3186, 3329, 3431, 3509, 3547 and 3576 cm−1 are assigned to water stretching vibrations. Broad infrared bands at 3170, 3322, 3419, 3450, 3493, 3542, 3577 and 3597 cm−1 are also assigned to water stretching vibrations. Infrared bands at 1330, 1352, 1389, 1407, 1421 and 1457 cm−1 are assigned to the antisymmetric stretching vibrations of trigonal boron. The observation of so many bands suggests that there is considerable variation in the structure of ezcurrite. Infrared bands at 1634, 1646 and 1681 cm−1 are assigned to water bending modes. The number of water bending modes is in harmony with the number of water stretching vibrations.

Effect of nitrification inhibitors (DMPP and 3MP+ TZ) on soil nitrous oxide emissions from a sub-tropical vegetable production system in Queensland, Australia

The use of nitrification inhibitors, in combination with ammonium based fertilisers, has been promoted recently as an effective method to reduce nitrous oxide (N2O) emissions from fertilised agricultural fields, whilst increasing yield and nitrogen use efficiency. Vegetable cropping systems are often characterised by high inputs of nitrogen fertiliser and consequently elevated emissions of nitrous oxide (N2O) can be expected. However, to date only limited data is available on the use of nitrification inhibitors in sub-tropical vegetable systems. A field experiment investigated the effect of the nitrification inhibitors (DMPP & 3MP+TZ) on N2O emissions and yield from a typical vegetable production system in sub-tropical Australia. Soil N2O fluxes were monitored continuously over an entire year with a fully automated system. Measurements were taken from three subplots for each treatment within a randomized complete blocks design. There was a significant inhibition effect of DMPP and 3MP+TZ on N2O emissions and soil mineral N content directly following the application of the fertiliser over the vegetable cropping phase. However this mitigation was offset by elevated N2O emissions from the inhibitor treatments over the post-harvest fallow period. Cumulative annual N2O emissions amounted to 1.22 kg-N/ha, 1.16 kg-N/ha, 1.50 kg-N/ha and 0.86 kg-N/ha in the conventional fertiliser (CONV), the DMPP treatment, the 3MP+TZ treatment and the zero fertiliser (0N) respectively. Corresponding fertiliser induced emission factors (EFs) were low with only 0.09 - 0.20% of the total applied fertiliser lost as N2O. There was no significant effect of the nitrification inhibitors on yield compared to the CONV treatment for the three vegetable crops (green beans, broccoli, lettuce) grown over the experimental period. This study highlights that N2O emissions from such vegetable cropping system are primarily controlled by post-harvest emissions following the incorporation of vegetable crop residues into the soil. It also shows that the use of nitrification inhibitors can lead to elevated N2O emissions by storing N in the soil profile that is available to soil microbes during the decomposition of the vegetable residues over the post-harvest phase. Hence the use of nitrification inhibitors in vegetable systems has to be treated carefully and fertiliser rates need to be adjusted to avoid excess soil nitrogen during the postharvest phase.

Canine-human transmission of Gastrospirillum hominis

We report electron microscopic evidence of transmission from a pet dog to a 12-year-girl of Gastrospirillum hominis which caused gastric disease in both that was eradicable with treatment. © 1994.

Volatile components associated with bacterial spoilage of tropical prawns

Analysis of headspace volatiles by gas chromatography/mass spectrometry from king (Penaeus plebejus), banana (P. merguiensis), tiger (P. esculentus/semisulcatus) and greasy (Metapenaeus bennettae) prawns stored in ice or ice slurry, which is effectively an environment of low oxygen tension, indicated the presence of amines at the early stages of storage (less than 8 days) irrespective of the nature of the storage media. Esters were more prevalent in prawns stored on ice (normal oxygen conditions) at the latter stages of storage (more than 8 days) and were only produced by Pseudomonas fragi, whereas sulphides and amines occurred whether the predominant spoilage organism was Ps.fragi or Shewanella putrefaciens. The free amino acid profiles of banana and king prawns were high in arginine (12–14%) and low in cysteine (0.1–0.17%) and methionine (0.1–0.2%). Filter sterilised raw banana prawn broth inoculated with a total of 15 cultures of Ps. fragi and S. putrefaciens and incubated for two weeks at 5°C, showed the presence of 17 major compounds in the headspace volatiles analysed using gas chromatography/mass spectrometry (GC/MS). These were mainly amines, sulphides, ketones and esters. Principal Component Analysis of the results for the comparative levels of the volatiles produced by pure cultures, inoculated into sterile prawn broth, indicated three subgroupings of the organisms; I, Ps. fragi from a particular geographic location; II, S. putrefaciens from another geographic location; and III, a mixture of Ps. fragi and S. putrefaciens from different geographic locations. The sensory impression created by the cultures was strongly related to the chemical profile as determined by GC/MS. Organisms, even within the same subgrouping classified as identical by the usual tests, produced a different range of volatiles in the same uniform substrate.

Productivity of the suffixes -ness and -ity in 17th-century English letters : A sociolinguistic approach

Tässä työssä tutkitaan englannin kielen substantiivijohtimien -ness ja -ity produktiivisuutta 1600-luvulla kirjoitetuissa kirjeissä. Näitä lähes synonyymisiä johtimia käytetään yleensä merkitykseltään abstraktien substantiivien muodostamiseen adjektiiveista (esim. productive 'produktiivinen' > productiveness tai productivity 'produktiivisuus'). Johtimista -ity on lainautunut englantiin ranskasta ja myöhemmin myös latinasta; se on sekä fonologialtaan että semantiikaltaan läpinäkymättömämpi kuin kotoperäinen -ness. Lisäksi -ity-johdinta on käytetty enimmäkseen formaaleissa tilanteissa ja tieteellisissä teksteissä, kun taas -ness on ollut yleiskäyttöisempi. Tutkielman lähestymistapa on sosiolingvistinen: oletetaan, että johtimien produktiivisuus (eli valmius muodostaa uusia johdoksia) voi vaihdella eri sosiaaliryhmissä. Sosiolingvistiikkaa ei ole aiemmin juurikaan sovellettu produktiivisuuden tutkimiseen. Tutkimusaineistona on Helsingin yliopiston VARIENG-tutkimusyksikön laatima Corpus of Early English Correspondence, varhaisista englanninkielisistä kirjeistä koostuva korpus eli elektroninen tekstikokoelma, joka on suunniteltu historiallisen sosiolingvistiikan tarpeisiin. Korpuksen 1600-luvun kirjeitten yhteenlaskettu pituus on noin 1,4 miljoonaa sanaa, ja ne on kirjoitettu vuosina 1600-1681. Tutkielman tärkeimpänä produktiivisuusmittarina käytetään johtimien avulla muodostettujen eri sanojen eli tyyppien lukumäärää. Hypoteesina on, että -ity-tyyppien määrä on keskimääräistä pienempi huonosti koulutettujen sosiaaliryhmien kirjeissä. Näitä olivat 1600-luvulla naiset sekä alhaisimmat yhteiskuntaryhmät, kuten talonpojat ja käsityöläiset. Johtimen -ness tyyppimäärissä ei odoteta esiintyvän sosiolingvististä variaatiota. Tutkielmassa käsitellään myös tyyppimäärien vertailuun liittyviä metodologisia ongelmia. Koska vaikkapa naisilta ja miehiltä on eri määrä dataa, ei heidän tyyppimääriään voida suoraan verrata keskenään. Esimerkiksi tyyppimäärien normalisointi tuhatta sanaa kohti ei myöskään ole mahdollista, koska tyyppien lukumäärä ei kasva lineaarisesti korpuksen kasvaessa. Tutkielmassa esitetään kielitieteessä harvoin käytetty tilastotieteellinen menetelmä, jonka avulla korpuksen eri osista saatuja tyyppimääriä voidaan verrata koko korpukseen ja testata, ovatko ne tilastollisesti merkittävän pieniä tai suuria. Toisin kuin monet yleisemmät menetelmät, tämä tyyppikertymiin ja permutaatiotesteihin perustuva metodi ei vaadi yksinkertaistavien oletuksien tekemistä. Tutkimustulokset vahvistavat hypoteesin oikeaksi: naisten -ity-tyyppien lukumäärä on tilastollisesti merkittävän alhainen, kun taas -ness-tyyppien määrissä ei ole tilastollisesti merkittäviä eroja. Alhaisimpien yhteiskuntaryhmien osalta tuloksia ei saada, koska niiltä on korpuksessa liian vähän dataa. Analyysissä paljastuu myös yllättävä eroavaisuus: korpuksen ajallisesti ensimmäisessä puoliskossa (1600-1639) on merkittävän vähän -ity-tyyppejä. Tämä voidaan tulkita kielelliseksi muutokseksi: -ity-johtimen produktiivisuus kasvaa kirjeissä 1600-luvun aikana. Saattaa olla, että johtimen produktiivisuus on ensin kasvanut formaalimmissa tekstilajeissa, joista lisääntynyt käyttö on sitten levinnyt myös kirjeisiin, ehkäpä 1640-luvun sisällissodan synnyttämien kontaktiverkostojen siivittämänä. Tuloksien perusteella voidaan sanoa, että sosiolingvistinen vaihtelu on merkittävä tekijä ainakin joittenkin johtimien produktiivisuudessa, joten vaihtelua on syytä tutkia enemmänkin. Tutkimuksessa käytetty metodi mahdollistaa osakorpuksien tyyppimäärien luotettavan vertailun melko pienissäkin korpuksissa, joten se soveltuu hyvin niin historialliseen kielitieteeseen kuin sosiolingvistiikkaankin.

Timing of fungicide applications for control of husk spot caused by Pseudocercospora macadamiae in macadamia

Pseudocercospora macadamiae is an important pathogen of macadamia in Australia, causing a disease known as husk spot. Growers strive to control the disease with a number of carbendazim and copper treatments. The aim of this study was to consider the macadamia fruit developmental stage at which fungicide application is most effective against husk spot, and whether application of copper-only applications at full-size fruit developmental stage toward the end of the season contributed to effective disease control. Fungicides were applied to macadamia trees at four developmental stages in three orchards in two subsequent production seasons. The effects of the treatments on disease incidence and severity were quantified using area under disease progress curve (AUDPC) and logistic regression models. Although disease incidence varied between cultivars, incidence and severity on cv. A16 showed consistent differences between the treatments. Most significant reduction in husk spot incidence occurred when spraying commenced at match-head sized-fruit developmental stage. All treatments significantly reduced husk spot incidence and severity compared with the untreated controls, and a significant positive linear relationship (R2 = 73%) between AUDPC and severity showed that timing of the first fungicide application is important for effective disease control. Application of fungicide at full-size fruit stage reduced disease incidence but had no impact on premature fruit drop.

X-ray absorption spectra of niobium dichalcogenides and their first-row transition-metal intercalates

X-ra!. K-absorption spectra of niobium in niobium dichalcogenides. namely NbS, and NbSe, and their first-row transition-metal intercalates Mi P 3N bSz (M = Cr. Mn. Fe. Co. Ni) and Ml#,NbSe2 (M = Fe. CO). have been measured together with those in niobium metal. The spectra of these materials are \er? similar to one another. They reflect the transitions to the partially filled niobium d band with some p character. A bariety of x-ray absorption nearedge structures (XASES) associated with the K edges of intercalated atoms are also presented and discussed.

Effect of foliar herbicides on the germination and viability of Siam weed (Chromolaena odorata) seeds located on plants at the time of application.

This paper reports a field study undertaken to determine if the foliar application of herbicides fluroxypyr (150 mL 100 L-1 a.i.) and metsulfuron-methyl (12 g 100 L-1 a.i.) were capable of reducing the germination and viability of Chromolaena odorata (L.) R.M.King & H.Rob. (Siam weed) seeds at three different stages of maturity. After foliar application of fluroxypyr germination of mature seeds was reduced by 88% and intermediate and immature seeds were reduced by 100%, compared to the control. Fluroxypyr also reduced the viability of mature, intermediate and immature seeds by 79, 89 and 67% respectively, compared to the control. Metsulfuron-methyl reduced germination of intermediate and immature seeds by 53 and 99% respectively compared to the control. Viability was also reduced by 74 and 96% respectively, compared to the control. Mature seeds were not affected by metsulfuron-methyl as germination and viability increased by 2% and 1% respectively, as compared to the control. These results show that these herbicides are capable of reducing the amount of viable seed entering the seed bank. However depending on the treatment and stage of seed development a percentage of seeds on the plants will remain viable and contribute to the seed bank. This information is of value to Siam weed eradication teams as plants are most easily located and subsequently treated at the time of flowering. Knowledge of the impact of control methods on seeds at various stages of development will help determine the most suitable chemical control option for a given situation.