Development of the selection and manipulation of self-generated thoughts in adolescence

The ability to select and manipulate self-generated (stimulus-independent, SI), as opposed to stimulus-oriented (SO), information, in a controlled and flexible way has previously only been studied in adults. This ability is thought to rely in part on the rostrolateral prefrontal cortex (RLPFC), which continues to mature anatomically during adolescence. We investigated (1) the development of this ability behaviorally, (2) the associated functional brain development, and (3) the link between functional and structural maturation. Participants classified according to their shape letters either presented visually (SO phases) or that they generated in their head by continuing the alphabet sequence (SI phases). SI phases were performed in the presence or absence of distracting letters. A total of 179 participants (7–27 years old) took part in a behavioral study. Resistance to visual distractors exhibited small improvements with age. SI thoughts manipulation and switching between SI and SO thoughts showed steeper performance improvements extending into late adolescence. Thirty-seven participants (11–30 years old) took part in a functional MRI (fMRI) study. SI thought manipulation and switching between SO and SI thought were each associated with brain regions consistently recruited across age. A single frontal brain region in each contrast exhibited decreased activity with age: left inferior frontal gyrus/anterior insula for SI thought manipulation, and right superior RLPFC for switching between SO and SI thoughts. By integrating structural and functional data, we demonstrated that the observed functional changes with age were not purely consequences of structural maturation and thus may reflect the maturation of neurocognitive strategies

Functional specialization within rostral prefrontal cortex (Area 10): a meta-analysis

One of the least well understood regions of the human brain is rostral prefrontal cortex, approximating Brodmann's area 10. Here, we investigate the possibility that there are functional subdivisions within this region by conducting a meta-analysis of 104 functional neuroimaging studies (using positron emission tomography/functional magnetic resonance imaging). Studies involving working memory and episodic memory retrieval were disproportionately associated with lateral activations, whereas studies involving mentalizing (i.e., attending to one's own emotions and mental states or those of other agents) were disproportionately associated with medial activations. Functional variation was also observed along a rostral-caudal axis, with studies involving mentalizing yielding relatively caudal activations and studies involving multiple-task coordination yielding relatively rostral activations. A classification algorithm was trained to predict the task, given the coordinates of each activation peak. Performance was well above chance levels (74% for the three most common tasks; 45% across all eight tasks investigated) and generalized to data not included in the training set. These results point to considerable functional segregation within rostral prefrontal cortex

The case for the development and use of "ecologically valid" measures of executive function in experimental and clinical neuropsychology

This article considers the scientific process whereby new and better clinical tests of executive function might be developed, and what form they might take. We argue that many of the traditional tests of executive function most commonly in use (e.g., the Wisconsin Card Sorting Test; Stroop) are adaptations of procedures that emerged almost coincidentally from conceptual and experimental frameworks far removed from those currently in favour, and that the prolongation of their use has been encouraged by a sustained period of concentration on “construct-driven” experimentation in neuropsychology. This resulted from the special theoretical demands made by the field of executive function, but was not a necessary consequence, and may not even have been a useful one. Whilst useful, these tests may not therefore be optimal for their purpose. We consider as an alternative approach a function-led development programme which in principle could yield tasks better suited to the concerns of the clinician because of the transparency afforded by increased “representativeness” and “generalisability.” We further argue that the requirement of such a programme to represent the interaction between the individual and situational context might also provide useful constraints for purely experimental investigations. We provide an example of such a programme with reference to the Multiple Errands and Six Element tests

Microbiological assessment and evaluation of rehydration instructions on powdered infant formulas, follow-up formulas, and infant foods in Malaysia

A total of 90 samples comprised of powdered infant formulas (51), follow-up formulas (21) and infant foods (18) from 15 domestic and imported brands were purchased from various retailers in Klang Valley, Malaysia and evaluated in terms of microbiological quality and the similarity of rehydration instructions on the product label to guidelines set by the World Health Organization. Microbiological analysis included the determination of aerobic plate count (APC) and the presence of Enterobacteriaceae and Cronobacter spp. Isolates of interest were identified using ID 32E (bioMerieux®). In this study 87% of powdered infant formulas, follow-up formulas and infant foods analyzed had aerobic plate counts below the permitted level of 70°C for formula preparation as specified by the 2008 revised World Health Organization guidelines. Six brands instructed the use of water at 40-55°C, a temperature range which would support the survival and even growth of Enterobacteriaceae

Effect of photoperiod and host distribution on the horizontal transmission of Isaria fumosorosea (Hypocreales: Cordycipitaceae) in greenhouse whitefly assessed using a novel model bioassay

A model bioassay was used to evaluate the epizootic potential and determine the horizontal transmission efficiency of Isaria fumosorosea Trinidadian strains against Trialeurodes vaporariorum pharate adults under optimum conditions (25±0.5°C, ~100% RH) at two different photoperiods. Untreated pharate adults were arranged on laminated graph paper at different distributions to simulate varying infestation levels on a leaf surface. Four potential hosts were located 7, 14 and 21 mm away from a central sporulating cadaver simulating high, medium and low infestation levels, respectively. Percent hosts colonized were recorded 7, 12, 14 and 21 days post-treatment during a 16- and 24-h photophase. After 21 days, mean percent hosts colonized at the highest, middle and lowest infestation levels were 93 and 100%, 22 and 58%, 25 and 39% under a 16- and 24-h photophase, respectively. From the results, it was concluded that the longer the photophase, the greater the percentage of hosts colonized, and as host distance increased from the central sporulating cadaver, colonization decreased. The use of this novel model bioassay technique is the first attempt to evaluate the epizootic potential and determine the horizontal transmission efficiency of I. fumosorosea Trinidadian strains under optimal environmental conditions at different photoperiods. This bioassay can be used to assess horizontal transmission efficiency for the selection of fungi being considered for commercial biopesticide development

The effects of conjugated linoleic acid isomers cis-9,trans-11 and trans-10,cis-12 on in vitro bovine embryo production and cryopreservation

Conjugated linoleic acid (CLA) isomers can affect the lipid profile and signaling of cells and thereby alter their function. A total of 5,700 bovine oocytes were used in a structured series of experiments to test the effects of CLA cis-9,trans-11 and CLA trans-10,cis-12 in vitro. In experiment 1, high doses of each CLA isomer during in vitro maturation (IVM) were compared with high or low doses during the entire in vitro culture (IVC) of parthenogenetic embryos. High doses of the CLA isomers ranged from 50 to 200 μM and low doses were 15 and 25 μM. In experiment 2, the low doses of each CLA isomer were tested during IVM/IVC on embryos produced by in vitro fertilization (IVF). Experiment 3 compared the effects of 15 μM doses of each CLA isomer during IVM or IVC of IVF embryos. In experiment 4, post-rewarming survival rates and blastomere counts were assessed for embryos supplemented with each CLA isomer during IVM or for 36 h before vitrification. In experiment 1, when either CLA isomer was provided only during IVM, we observed no effects on overall rates of maturation, cleavage, or blastocysts (92.2 ± 1.6%, 78.3 ± 4.1%, and 28.9 ± 5.1%, respectively). However, high doses of each CLA isomer, but not low doses, during the entire embryo culture period decreased blastocyst rates (5-20%) in a dose-dependent manner. Cleavage rates improved with 15 or 50 μM CLA trans-10,cis-12. Progesterone concentrations in maturation media were significantly increased by high doses of each CLA isomer compared with control, but low doses of CLA isomers had no effect. In experiment 2 with IVF embryos, low doses of each CLA isomer did not alter cleavage rates (average 84.9 ± 1.9%) and only 25 μM CLA trans-10,cis-12 during IVC reduced blastocyst rates below those of controls (25.5 ± 2.1 vs. 38.2 ± 2.3%). The lipid content of embryos was increased and relative expression of the BIRC5 (baculoviral IAP repeat containing 5) gene was depressed by CLA trans-10,cis-12. In experiment 3, low doses (15μM) of each CLA isomer during IVC significantly reduced blastocyst rates (20.6 ± 2.4% and 27.7 ± 1.2% vs. 34.18 ± 1.2% for CLA trans-10,cis-12 and CLA cis-9,trans-11 compared with control, respectively) with less effect of each CLA during IVM. In experiment 4, adding 100 μM CLA cis-9,trans-11 during the final 36 h of culture resulted in a high survival rate after rewarming and culture, and the higher embryo blastomere count was comparable to that of control embryos not undergoing vitrification. In conclusion, supplementation with either CLA isomer did not improve embryo production, but inclusion of CLA cis-9,trans-11 before vitrification improved the quality of bovine IVF embryos after rewarming and culture

Long-term trends in tropical cyclone tracks around Korea and Japan in late summer and early fall

This study investigates long-term trends in tropical cyclones (TCs) over the extratropical western North Pacific (WNP) over a period of 35 years (1982-2016). The area analyzed extended across 30-45 degrees N and 120-150 degrees E, including the regions of Korea and Japan that were seriously affected by TCs. The northward migration of TCs over the WNP to the mid-latitudes showed a sharp increase in early fall. In addition, the duration of TCs over the WNP that migrated northwards showed an increase, specifically in early to mid-September. Therefore, more recently, TC tracks have been observed to significantly extend into the mid-latitudes. The recent northward extension of TC tracks over the WNP in early fall was observed to be associated with changes in environmental conditions that were favorable for TC activities, including an increase in sea surface temperature (SST), decrease in vertical wind shear, expansion of subtropical highs, strong easterly steering winds, and an increase in relative vorticity. In contrast, northward migrations of TCs to Korea and Japan showed a decline in late August, because of the presence of unfavorable environmental conditions for TC activities. These changes in environmental conditions, such as SST and vertical wind shear, can be partially associated with the Pacific decadal oscillation

What are the impacts of within-field farmland management practices on the flux of greenhouse gases from arable cropland in temperate regions? A systematic map protocol

Background: Reducing greenhouse gas emissions is a vital step in limiting climate change and meeting the goals outlined in the COP 21 Paris Agreement of 2015. Studies have suggested that agriculture accounts for around 11% of total greenhouse gas emissions and the industry has a significant role in meeting international and national climate change reduction objectives. However, there is currently little consensus on the mechanisms that regulate the production and assimilation of greenhouse gases in arable land and the practical factors that affect the process. Practical advice for farmers is often overly general, and models based on the amount of nitrogen fertiliser applied, for example, are used despite a lack of knowledge of how local conditions affect the process, such as the importance of humus content and soil types. Here, we propose a systematic map of the evidence relating to the impact on greenhouse gas flux from the agricultural management of arable land in temperate regions. Methods: Using established methods for systematic mapping in environmental sciences we will search for, collate and catalogue research studies relating to the impacts of farming in temperate systems on greenhouse gas emissions. We will search 6 bibliographic databases using a tested search string, and will hand search a web-based search engine and a list of organisational web sites. Furthermore, evidence will be sought from key stakeholders. Search results will then be screened for relevance at title, abstract and full text levels according to a predefined set of eligibility criteria. Consistency checking will be employed to ensure the criteria are being applied accurately and consistently. Relevant studies will then be subjected to coding and meta-data extraction, which will be used to populate a systematic map database describing each relevant study's settings, methods and measured outcomes. The mapping process will help to identify knowledge gaps (subjects lacking in evidence warranting further primary research) and knowledge clusters (subjects with sufficient studies to allow a useful full systematic review), and will highlight best and suboptimal research methods