Production and use of agrofibre in Finland : final report study, IV part : reed canary grass sulphate pulp as raw material for fine paper

Suomen oloissa lyhytkuituista ruokohelpeä on mahdollista käyttää hienopaperin raaka-aineena. Ruokohelven kuitupituus ja pituusmassa ovat hieman alhaisemmat kuin koivumassalla, mistä on seurauksena suuri kuitumäärä massayksikössä. Non-wood-kuitujen tapaan ruokohelvelle on tyypillistä suuri hienoainemäärä, joka huonontaa massan suotautuvuutta. Koivuun verrattuna ruokohelpi sisältää vähemmän ligniiniä ja selluloosaa, mutta huomattavasti enemmän tuhkaa ja silikaattia. Ruokohelpi keittyy helposti kappalukuun 10 ja saanto on hyvä. Ruokohelpimassaa ei tarvitse happidelignifioida. Valkaisemattoman ruokohelpimassan ja happidelignifioidun koivumassan vaalenevuudessa ei ollut eroja. Fraktioitu, kyyppipesty ja happidelignifioitu ruokohelpi vaaleni myös TCF-sekvenssillä täysvaaleuteen kemikaalikulutusten ollessa varsin kohtuullisia. Ruokohelven korkea silikaattipitoisuus (1-5 %) aiheuttaa ongelmia talteenottolinjalla, jos sitä ei huomioida prosessia suunniteltaessa. Lehtimateriaalin ja pölyn poisto fraktioinnilla ennen keittoa pienentää silikaattipitoisuutta noin 40 %. Mustalipeästä silikaatti voidaan poistaa käyttämällä kaupallisia menetelmiä: saostamalla savukaasuilla tai kaksivaiheisella kaustisoinnilla. Lyhytkuituinen ruokohelpimassa antaa hienopaperille hyvät painettavuusominaisuudet, kun taas ajettavuuden edellyttämä lujuus saadaan pitkäkuituisella havumassalla. Ruokohelpikuidulla on hyvä sitoutumiskyky, joten sitä ei tarvitse jauhaa. Ruokohelpimassan repäisylujuus on pienempi, mutta murtotyö suurempi kuin jauhetulla koivumassalla. Myös ilmanläpäisyvastus on jonkin verran suurempi. Erot ovat kuitenkin koivumassan ominaisuusvaihteluiden rajoissa. Ruokohelven suuri kuitumäärä massayksikössä takaa massalle hyvät valonsirontaominaisuudet. Ruokohelven kasvupaikan maalaji ja korjuuajankohta aiheuttavat suuria vaihteluita raaka-aineen ominaisuuksiin. Kun ruokohelpi tuottaa runsaasti kortta, kasvaa multamaalla ja korjataan keväällä, siitä keitetyn massan saanto ja paperitekninen potentiaali hienopaperissa ovat samaa luokkaa koivumassan kanssa. Vaikka puhtaan ruokohelpimassan vedenpoisto-ominaisuudet ovat huonommat kuin koivumassan, laboratoriosimulointikokeet osoittivat, ettei näiden massojen välillä ole eroja rainan kosteuspitoisuudessa ennen puristinosaa eikä sen jälkeen. Kuivatussimulointikokeiden perusteella voi ruokohelpeä sisältävän paperin loppukosteus jäädä korkeammaksi kuin puumassasta valmistetun paperin ainoastaan silloin, kun kuivatusosa muodostaa "pullonkaulan" paperikoneessa. Pilotpaperikoneella tehdyissä kokeissa ei höyrynkulutuksessa eikä kuivaussylintereiden lämpötiloissa havaittu eroja lisättäessä ruokohelpimassan osuutta pohjapaperissa. Entsyymikäsittelyllä voidaan tarvittaessa parantaa ruokohelpimassan vedenpoistokykyä. Laboratoriomitassa saadut tulokset ruokohelpimassan soveltuvuudesta hienopaperin raaka-aineeksi varmistettiin pilotmittakaavaisissa koeajoissa, joissa valmistettiin päällystettyä ja pintaliimattua hienopaperia. Paperia koepainettiin arkkioffsetpainokoneella. Pilotkoeajojen perusteella ruokohelpimassalla voidaan joko osittain tai kokonaan korvata koivusellu päällystetyssä ja pintaliimatussa hienopaperissa ajettavuuden tai laadun kärsimättä.Reed canary grass is a potential producer of short fibre for fine paper in Finland. Its fibre length and coarseness are somewhat lower than those of birch, yielding a large amount of particles per unit weight of pulp. Like other non-wood fibres, reed canary grass has a high fines content, which impairs the dewatering properties of pulp. Reed canary grass pulp contains less lignin and cellulose but much more ash and silica than birch pulp. Reed canary grass cooks easily to kappa level 10 and the yield is good. No oxygen delignification is needed. There were no differences in bleachability between unbleached reed canary grass pulp and oxygen-delignified birch pulp. When fractionated and pre-washed reed canary grass was used, full brightness was also reached with oxygen-delignified TCF pulp, chemical consumption still being very reasonable. The high silicon content of reed canary grass, 1-5%, causes problems in the recovery system if not taken into account in the process design. The removal of leaves and dust with air fractionation before cooking decreases the silicon content by about 40%. Silicon can be removed from black liquor with commercial desilication techniques, by precipitation with flue gases or by two-stage causticization. Short-fibred reed canary grass pulp gives fine paper good printing properties, while the strength required for runnability is adjusted by adding long-fibred softwood pulp. Reed canary grass fibres have a good bonding ability and need not be refined. The tear strength of the pulp is lower than that of refined birch pulp, but the TEA is higher; Air resistance is also somewhat higher. The differences are, however, within the limits of the property variations of mill birch pulp. The large amount of particles per unit weight of reed canary grass guarantees that the paper has good light scattering properties. Reed canary grass raw material properties are highly dependent on both the soil type at the growing place and the development stage of the plant at harvest. If reed canary grass is grown in humus-rich soil, produces a large stem fraction and is harvested by the delayed harvesting system, its pulp yield and papermaking potential are comparable to those of birch pulp. Although the dewatering ability of pure reed canary grass pulp is inferior to that of birch pulp, laboratory simulation tests showed that there are no differences in sheet dryness before or after pressing irrespective of whether birch or reed canary grass is used as the short-fibre pulp. Drying results indicate that only if the paper machine is drying-limited is there a possibility that the end moisture content of paper will be higher if reed canary grass is used in the furnish instead of woodpulp. When the proportion of reed canary grass pulp in the base paper was increased in pilot paper machine trials, no differences could be detected in steam consumption or in drying cylinder temperatures. Dewatering of reed canary grass pulp can be improved with enzymatic treatment if necessary. The results of the laboratory tests were confirmed in pilot-scale trials by making coated and surface-sized fine paper and by testing the printability of the paper in offset printing. The trials indicated that birch pulp can be replaced in part or entirely by reed canary grass pulp in coated or surface-sized fine paper without adversely affecting the runnability or the quality of the paper.vokMyynti MTT tietopalveluyksikk

Prophylaxis for venous thromboembolic disease in pregnancy and the early postnatal period

Some women are at risk of forming blood clots in a deep vein during pregnancy, after a caesarean birth, or during the first few weeks after childbirth. If part of the clot breaks off and lodges in a blood vessel in the lungs, it can be life-threatening. Preventive treatments include blood-thinning drugs to prevent clots, support stockings, and exercise soon after the birth to keep circulation moving. However, some drugs might cause problems such as increased blood loss after the birth. Drugs used include heparin, low molecular weight heparin and aspirin. We included 16 randomised controlled studies in the review but only 13 trials with 1774 women contributed data for the outcomes of interest. We did not find enough evidence from the trials to be sure about the effects of these different preventive treatments.This means there is not enough evidence to show which are the best ways to prevent deep vein thrombosis (DVT) during or following pregnancy, or after a caesarean birth

Paternal mental health trajectory classes and early fathering experiences : Prospective study on a normative and formerly infertile sample

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Early Family Relationships Predict Children’s Emotion Regulation and Defense Mechanisms

Early family relationships have been suggested to influence the development of children’s affect regulation, involving both emotion regulation and defense mechanisms. However, we lack research on the specific family predictors for these two forms of affect regulation, which have been conceptualized to differ in their functions and accessibility to consciousness. Accordingly, we examine how the (a) quality and (b) timing of family relationships during infancy predict child’s later emotion regulation and defense mechanisms. Parents (N = 703) reported autonomy and intimacy in marital and parenting relationships at the child’s ages of 2 and 12 months, and the child’s use of emotion regulation and immature and neurotic defenses at 7 to 8 years. As hypothesized, the results showed that functional early family relationships predicted children’s efficient emotion regulation, whereas dysfunctional relationships predicted reliance on defense mechanisms in middle childhood. Further, results showed a timing effect for neurotic defenses, partially confirming our hypothesis of early infancy being an especially important period for the development of defense mechanisms. The findings are discussed from the viewpoints of attachment and family dynamics, emotional self-awareness, and sense of security</p

Early family system types predict children's emotional attention biases at school age

The family environment shapes children's social information processing and emotion regulation. Yet, the long-term effects of early family systems have rarely been studied. This study investigated how family system types predict children's attentional biases toward facial expressions at the age of 10 years. The participants were 79 children from Cohesive, Disengaged, Enmeshed, and Authoritarian family types based on marital and parental relationship trajectories from pregnancy to the age of 12 months. A dot-probe task was used to assess children's emotional attention biases toward threatening (angry) and affiliative (happy) faces at the early (500 ms) and late (1250 ms) stages of processing. Situational priming was applied to activate children's sense of danger or safety. Results showed that children from Cohesive families had an early-stage attentional bias toward threat, whereas children from Enmeshed families had a late-stage bias toward threat. Children from Disengaged families had an early-stage attentional bias toward threat, but showed in addition a late-stage bias away from emotional faces (i.e., both angry and happy). Children from Authoritarian families, in turn, showed a late-stage attentional bias toward emotional faces. Situational priming did not moderate the effects of family system types on children's attentional biases. The findings confirm the influence of early family systems on the attentional biases, suggesting differences in the emotion regulation strategies children have developed to adapt to their family environments.Peer reviewe

Role of Androgen Receptor CAG Repeat Polymorphism and X-Inactivation in the Manifestation of Recurrent Spontaneous Abortions in Indian Women

The aim of the present study was to investigate the role of CAG repeat polymorphism and X-chromosome Inactivation (XCI) pattern in Recurrent Spontaneous Abortions among Indian women which has not been hitherto explored. 117 RSA cases and 224 Controls were included in the study. Cases were recruited from two different hospitals - Lakshmi Fertility Clinic, Nellore and Fernandez Maternity Hospital, Hyderabad. Controls were roughly matched for age, ethnicity and socioeconomic status. The CAG repeats of the Androgen Receptor gene were genotyped using a PCR-based assay and were analysed using the GeneMapper software to determine the CAG repeat length. XCI analysis was also carried out to assess the inactivation percentages. RSA cases had a significantly greater frequency of allele sizes in the polymorphic range above 19 repeats (p = 0.006), which is the median value of the controls, and in the biallelic mean range above 21 repeats (p = 0.002). We found no evidence of abnormal incidence of skewed X-inactivation. We conclude that longer CAG repeat lengths are associated with increased odds for RSA with statistical power estimated to be ∼90%