Cordierite-bearing lavas from Jaguarao, southern Brazil: Petrological evidence for crustal melts during early rifting of Gondwana

The Jaguarao stratoid dacites (Rio Grande do Sul, Brazil) are limited in areal extent, are comprised of about 3.2 km(3) of preserved erupted material, and outcrop only in areas of the region underlain by mylonitic and ultramylonitic rocks. They are S-type volcanic rocks containing cordierite, orthopyroxene, plagioclase, and ilmenite as liquidus phases, and partially melted granite, gneiss, and migmatite enclaves that are very similar to the Precambrian basement rocks. The Jaguarao lavas have distinct geochemical signatures and Sr-Nd isotopes with respect to other volcanic rocks of the region. Available geochronological data for Jaguarao dacites range between 157 +/- 5 Ma and 139.6 +/- 7.4 Ma. Considering the errors, the younger ages obtained for Jaguarao lavas overlap the 138-128 Ma age of rocks of the Serra Geral Group, and thus indicate that the dacites were erupted prior to the break-up of Gondwana in this region. Petrographic, mineralogical, and petrochemical data, as well as the tectonic context of the Jaguarao lavas, suggest that magma genesis was linked, at least in part, to friction melts. The dacitic magma was generated by partial melting reactions involving biotite breakdown in a dominantly quartz-feldspathic source terrane, leaving a granulite facies residue in subsurface. These melts were probably generated as a consequence of crustal thinning linked to simple shear extension just prior to Gondwana break-up and rifting of the southern Atlantic Ocean. (C) 2009 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Lower and Upper Neoproterozoic magmatic records in Itaiacoca Belt (Parana-Brazil): Zircon ages and lithostratigraphy studies

The Itaiacoca Belt is a sequence of metavolcanic and metasedimentary rocks that crop out east of Parana and southeast of Sao Paulo states, in southern Brazil. This geologic-geochronologic study supports division of the Itaiacoca Belt into two major lithologic sequences. The older is a carbonate platform sequence (dolomitic meta-limestones/metamarls/calc-phyllites/ carbonate phyllites) with minimum deposition ages related to the end of the Mesoproterozoic/beginning of the Neoproterozoic (1030-908 Ma:U-Pb, zircon of metabasic rocks). The younger sequence contains mainly clastics deposits (meta-arkoses/metavolcanics/metaconglomerates/metapelites) with deposition ages related to the Neoproterozoic (645-628 Ma:U-Pb,zircon of metavolcanic rocks). These ages are quite close to K-Ar ages (fine fraction) of the 628-610 Ma interval, associated with metamorphism and cooling of the Itaiacoca Belt. The contact between the dolomitic meta-limestones and meta-arkoses is marked by intense stretching and high-angle foliation, suggesting that the discontinuity between these associations resulted from shearing. It is proposed here that the term Itaiacoca Sequence, should represent the dolomitic meta-limestones, and the term Abapa Sequence represents the meta-arkoses/metavolcanics/phyllites. in a major tectonic context, these periods are related to the break-up of Rodinia Supercontinent (1030-908 Ma) and the amalgamation of the Gondwana Supercontinent (645-628 Ma). (C) 2008 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

U-Pb-Hf-trace element systematics and geochronology of zircon from a granulite-facies metamorphosed mafic-ultramafic layered complex in Central Brazil

Zircon recrystallization is a common process during high-grade metamorphism and promotes partial or complete resetting of the original isotopic and chemical characteristics of the mineral and thus complicates U-Pb geochronological interpretation. In Central Brazil, this complexity may be illustrated by three composite mafic-ultramafic intrusions metamorphosed under amphibolite-to-granulite conditions. Their ages of emplacement and metamorphic ages have been a matter of controversy for the last thirty years. The Serra da Malacacheta and Barro Alto complexes make up the southernmost of these layered bodies and four samples from distinct rock types were investigated in order to verify the consequences of metamorphic alteration of zircon for U-Pb dating. Cathodoluminescent imaging reveals internal features which are typical of concomitant dissolution-reprecipitation processes, such as convolute zoning and inward-moving recrystallization fronts, even in samples in which partially preserved igneous textures are observed. Due to this extensive alteration, LA-ICPMS U-Pb isotopic analysis yielded inconclusive data. However, in situ Hf isotopic and trace-element analyses help to clarify the real meaning of the geochronological data. Low Lu/Hf (<0.004) and homogeneous (176)Hf/(177)Hf(t) values imply that the zircon populations within individual samples have crystallized in a single episode, despite the observed variations in age values. Trace element signatures of zircon grains from garnet-bearing samples reveal that they were unreactive to the development of the peak metamorphism mineral assemblage and, thus, the main chemical feature in such grains is attributed to a coupled dissolution-reprecipitation process. However, in the Cafelandia amphibolite an additional alteration process is identified, probably related to the influx of late-stage fluids. Combined isotopic and geochemical investigation on zircon grains allowed the distinction of two magmatic events. The first corresponds to the crystallization of the Serra da Malacacheta Complex and characterizes a juvenile magmatism at similar to 1.3 Ga. The younger episode, recognized in the Barro Alto Complex, is dated at ca. 800 Ma and is represented by mafic and ultramafic rocks showing intense contamination with continental crust, implying that the emplacement took place, most likely, in a continental back-arc setting. Altered zircon domains as well as titanite grains date the metamorphic event at ca. 760-750 Ma. (C) 2011 Elsevier B.V. All rights reserved.

Patriarchal values : girls are more apt to change

Patriarchal values: girls are more apt to change How has the family value system changed between generations, especially when taking into account the gender dimension? This article presents some results from a study carried outin 2007 in one village of the Gourani tribe where the people are followers of Ahle Hagh in Islamabad Gharb (west of Iran). The differences between generations (those born and raised before and after the Islamic Revolution) in patriarchal values in the family are statistically significant. The older generation opts for the man of the family to make most of the decisions; on children’s education, marriage, naming, the families expenditure, the place for residence, the social network of the family and even the number of children. The younger generation has a different value system and it has moved towards a more egalitarian type of family. With the gender variable included in the findings we see that although the values of the younger male population have evolved toward a less patriarchal decision making structure inthe family, the degree of changes among the young women is much higher. Looking into the preferences for male sex for the first child as well as a larger number of boys in the family, the difference between generations is significant. However data on the differences analyzed with the gender variable proves that the changes concerning the equality of sexes are mainly due to drastic changes in the young women’s value system. That is, the male population, young or old, still prefer to have a boy as their first born and to have more sons in the family. But the young female generation in the rural area sees less difference in having boys or girls in the family. It is concluded that reforms in the old value system is an evolving process of everyday life and that the girls are the main social force for change.

Unga vuxnas upplevelse av sjuksköterskans bemötande av psykisk ohälsa vid kontakt med hälso- och sjukvården - en litteraturöversikt

Bakgrund: Unga vuxna som sökte vård sökte oftast inte för den psykiska ohälsan utan istället för något somatiskt. Det är viktigt att få de yngre vuxna att söka sig till vården när behov uppstår och underlätta till en god förbindelse mellan sjukvården och de unga vuxna. Syfte: Syftet med denna studie var att beskriva unga vuxnas upplevelser av sjuksköterskans bemötande av psykisk ohälsa vid kontakt med hälso- och sjukvården. Metod: Studien genomfördes som en litteraturöversikt. Resultat: För de unga vuxna var det inte lätt att komma in i vården på rätt vårdnivå om personen inte kom i kontakt med en sjuksköterska som hade ett holistiskt synsätt. Vården för de unga med psykisk ohälsa bör vara tillgänglig och informationen om tillgängligheten behöver ständigt upprepas. Slutsats: Det är viktigt att sjuksköterskor har kunskap och erfarenhet av unga psykiska människor för att kunna hjälpa dem med den psykiska ohälsan när de söker vård. Relationen mellan patienten och sjuksköterskan är av stor vikt för den fortsatta kontakten med vården för den unge vuxna. Det är viktigt att de känner tillit och förtroende.

Mot ökad diskursivitet? : Skrivutveckling speglad i provtexter från årskurs 5 och årskurs 9

Drawing onobservations in texts from the national test in Swedish, the report discusses tworelated questions: 1) whether students develop their writing abilities betweengrades 5 and 9, two measuring points in the system of national tests in Swedish,and 2) how this development might be measured. In the study, two samples ofschool texts – from grades 5 and 9 respectively – were compared in terms of textlength, sentence length and genre match at a macro level. A more detailedanalysis of lexical concentration and text structure was performed on a narrowersample of twenty texts from each school grade. The comparison showed that theolder pupils write longer texts, with longer sentences and a more varied textstructure. The younger children, however, produce texts with higher lexicalconcentration – which might be construed as a higher degree of textual content –and they follow the given genre instructions more closely.

Subjective quality of life, perceived control and dispositional optimism among older people

Objectives: To examine whether the subjective quality of life (QOL) of elderly people is held under homeostatic control, and to investigate the role of perceived control and dispositional optimism in the maintenance of subjective QOL.
Method: 100 older people (M=75.6 years) and a control group of 107 younger people (M=20.1 years) completed a self-report survey.
Results: Both groups had a level of subjective QOL within the normal range. The older group reported higher levels of secondary control and optimism, but similar levels of primary control, as the younger group. Primary control and optimism predicted subjective QOL for both groups. Secondary control was a significant predictor (or the younger group, however it was only marginally significant for the older group. Optimism accounted for the most subjective QOL variance for both groups.
Conclusions: The finding that the subjective QOL of the older group lay within the normative range supports the proposal that their subjective QOL is being successfully maintained under bomeostatic control. However, they appear to have an increased reliance on secondary control. The fact that dispositional optimism captures the predictive variance of perceived control, is an important finding adding to the understanding of subjective QOL maintenance.

Gait termination in young and older adults : effect of stopping stimulus probability and stimulus delay

Sixteen young (25±2.6 years) and 16 older individuals (69±4.4 years) walked normally then terminated walking rapidly. A visual stopping stimulus was presented 10 ms following ground contact (short delay) and in another condition, at 450 ms prior to toe-off (long delay). Stimulus probability was either high (80% of trials) or low (10%). The younger group stopped faster (463 vs. 574 ms) despite also walking faster (1.29 vs. 1.17 m s⁻¹). Longer delay decreased one-step responses but older participants used significantly more (slower) two-step stopping, which increased stopping time and distance. The additional step may have been pre-planned to maintain medial–lateral stability.

Ageing effects on visual reaction time in a single task condition and when treadmill walking

Visual reaction time (RT) was measured in 10 older men (mean age, 71.1 years) and gender-matched controls (mean age, 26.3 years) when standing (single task) and when walking on a motor-driven treadmill (dual task). There were 90 quasirandomly presented trials over 15 min in each condition. Longer mean and median RTs were observed in the dual task compared to the single task. Older males had significantly slower mean and median RTs (315 and 304 ms, respectively) than the younger group (273 and 266 ms, respectively) in both task conditions. There were no age or condition effects on with in-subject variability. Both groups showed a trend of increasing RT over the 90 single task trials but when walking only the younger group slowed. These novel findings demonstrate high but sustained attention by older adults when walking. It is proposed that the motor task's attentional demands might contribute to their slower preferred walking speed.

Changes in weight and waist circumference over 9 years in a Scottish population

Objective: To document patterns of measured weight and waist circumference (WC) change and the increase in overweight and obesity over a 9-year period. Subjects/Methods: A total of 1044 subjects from two age-defined cohorts aged 39 and 59 in 1991. Height, weight and WC were measured in 1991, 1995 and 2000 and body mass index (BMI) was calculated. Pattern of weight and WC change was studied over approximately 9 years. Results: The prevalence of overweight and obesity increased markedly and the younger cohort showed greater increases in weight and WC than the older cohort. There was no significant difference in mean BMI and/or mean 9-year weight change between men and women in either age cohort, and mean weight gain was similar for all occupational groups. Only 20% of subjects maintained a stable weight (plusminus2 kg), while 42.2 and 17.6% gained greater than 5 and 10 kg over the 9-year period, respectively. The rate of weight gain appeared to be relatively steady over the 9 years among younger subjects but declined in the older subjects in the second half of the observation period. Conclusions: Health promotion strategies to prevent weight gain need to be population-based, targeting all social and age groups, but particularly those in their early middle-age.

Age and walking speed effects on muscle recruitment in gait termination

During gait termination at normal walking speed, older adults more frequently employ two-step responses, increasing their stopping distance and stopping time more than younger controls. This study investigated ageing effects on lower limb muscle recruitment patterns during stopping at three walking speeds. Twelve young male (26±3.7 years, range 19–30) and 12 gender-matched older participants (72±4.3 years, range 65–82) terminated walking at normal, medium and maximum speed. A visual stopping stimulus was presented 10 ms following either left or right heel-contact with no stimulus (catch) on 30% of trials. Electromyographic (EMG) activity was recorded from the tibialis anterior (TA), soleus (SOL), biceps femoris (BF), vastus lateralis (VL) and gluteus medius (GM). Older males more frequently (46% of trials) took two-steps to stop than young males (20%). The stance leg muscles responded significantly faster than the swing leg, and with increased speed, fewer swing limb muscles contributed to stopping. Older males were slower to respond with the stance leg, at 215 ms following the stimulus compared with 176 ms for the younger group. They also recruited fewer swing leg muscles with less frequent activation of the soleus and gluteus medius. Failure to activate muscles would provide less extensor torque to maintain the centre of gravity anterior to the forward base of support. This would decrease the total force opposing horizontal velocity in order to bring the body to rest and, as a consequence, encourage an additional step prior to stopping.

Replication of hepatitis B in HBsAg-positive siblings

Persistent hepatitis B virus (HBV) replication is important for progression of chronic liver diseases. To understand whether there is a trend of HBV replication in siblings or not, 1850 relatives of patients with hepatocellular carcinoma (HCC) were examined prospectively for liver function test, viral markers and HBV DNA. The prevalence of HBsAg in the parents', siblings', children's and grandchildren's generations were 43.4%, 57.2%, 35.5% and 32.1%, respectively. The prevalence of hepatitis B e antigen (HBeAg) in sibling's generation (mean age 44.4 years) was 19%, which is higher than that of asymptomatic HBsAg carriers. For siblings in the children's generation, the prevalence of HBeAg in hepatitis B surface antigen (HBsAg) carriers declined from 40% in the eldest siblings to 19% in the youngest siblings. In 75 families clustered with three or more HBsAg carrier siblings, the mean age for seven families of which all siblings remained HBeAg + was younger, whereas the mean age for 35 families of which all siblings had cleared HBeAg was older. For the remaining 33 families, in only 10 families had the older siblings cleared the HBeAg earlier than the younger siblings. Twenty families showed that younger siblings cleared the HBeAg earlier than the older or middle siblings. We concluded that HBV replication in HCC relatives cannot be explained by familial tendency alone. A significant number of younger siblings appeared to have a shorter HBV replication phase than their older siblings. The possible role of this in maternal–fetal transmission is discussed.

Spring into summer : a novel

Spring into Summer is a novel based on my experiences as a student living in London for a year. The central character, an American under-graduate student studying history, attempts to complete a piece of work by his older brother who is killed in a car accident several months prior to his brother's departure for England. The narrative traces the younger brother's efforts and eventual failure to work on the history; in so doing, he also fails to become more like his older brother whom he greatly loved and admired. Thus, a doppelganger, or "Double" of sorts is used. Most of the action of the novel is set in London. However, the main character also travels to Dublin, York, and several other places in the British Isles, thereby giving a more complete picture of the experiences an American student undergoes while living abroad. During a year which many people might see as an escape from the problems and pressures of everyday life, the central character is forced to undergo a painful process of self-examination, resulting in his reevaluation of himself, his priorities, and his ambitions.

Children's conception of police authority when responding to requests for assistance

Children (five to six and seven to eight years old) were presented with scenarios in which various adults (a police officer, a teacher, and an unspecified adult) requested assistance from a child. Six scenarios were presented (two per adult) with half involving a reasonable request (requiring little effort from the child) and the others unreasonable. For each scenario, the participants stated: (i) whether the child in the story should comply with the adult's request, (ii) the reason for the compliance decision, (iii) the consequences of non-compliance, and (iv) the legitimacy of the adult's request. Compliance and perceived legitimacy of the request was highest for the police officer compared to the teacher, with both figures commanding greater compliance than the unspecified adult. Children's justifications suggested that the positive relationship between obedience and social status was due (albeit in part) to fear of punishment for non-compliance, particularly in the younger age group.

Vietnamese-born health professionals : negotiating work and life in rural Australia

Introduction: Australia is a culturally diverse nation due to migrants from a wide variety of countries creating a multicultural society. The health professions are highly valued by the younger generation of overseas-born migrants who have acculturated into Australian society; many have chosen health care as their profession in Australia. However, most migrants settle in metropolitan areas and young health professionals may find working in rural or remote Australia culturally and professionally highly challenging. The present study of migrant health professionals examined the life experiences and acculturation strategies of Vietnamese-born health professionals working and living in rural Australia. Objectives: The two main study objectives were to: (1) examine aspects of the acculturation of overseas-born and Australian-trained health professionals in the Australian health discourse; and (2) identify key coping strategies used by them when in working in the rural context.

Methods: Six overseas-born, Australian-trained health professionals were invited to participate in this qualitative study using a snowball sampling technique. The participants were all born in Vietnam and had experienced working in rural Australia. They included three medical doctors, a dentist, a physiotherapist and a nurse. The interviews were recorded and four participants also provided additional written responses to some of the open-ended interview questions. The interview data were transcribed and later coded for thematic analysis. Topics and themes that emerged focused on the issues and strategies of acculturation to the rural health context.

Results: The study showed that the acculturation process was affected by the participants’ views about and attitudes towards working in an Australian rural context. The study identified these essential strategies used by the participants in adapting to a new workplace: collaborating, distancing, adjusting, repairing, and accommodating.

Conclusion: The study provides insights into the lives of these health professionals in a rural context, and particularly their experience of cultural shock and the coping strategies they may use. A need is identified for a larger study to inform recruitment and retention of these health professionals to rural Australia, and to assist universities to prepare such students and their clinical supervisors for rural placements.