Decade Extensive Research Research Articles

Brain parcellation selection: An overlooked decision point with meaningful effects on individual differences in resting-state functional connectivity

Over the past decade extensive research has examined the segregation of the human brain into large-scale functional networks. The resulting network maps, i.e. parcellations, are now commonly used for the a priori identification of functional networks. However, the use of these parcellations, particularly in developmental and clinical samples, hinges on four fundamental assumptions: (1) the various parcellations are equally able to recover the networks of interest; (2) adult-derived parcellations well represent the networks in children's brains; (3) network properties, such as within-network connectivity, are reliably measured across parcellations; and (4) parcellation selection does not impact the results with regard to individual differences in given network properties. In the present study we examined these assumptions using eight common parcellation schemes in two independent developmental samples. We found that the parcellations are equally able to capture networks of interest in both children and adults. However, networks bearing the same name across parcellations (e.g., default network) do not produce reliable within-network measures of functional connectivity. Critically, parcellation selection significantly impacted the magnitude of associations of functional connectivity with age, poverty, and cognitive ability, producing meaningful differences in interpretation of individual differences in functional connectivity based on parcellation choice. Our findings suggest that work employing parcellations may benefit from the use of multiple schemes to confirm the robustness and generalizability of results. Furthermore, researchers looking to gain insight into functional networks may benefit from employing more nuanced network identification approaches such as using densely-sampled data to produce individual-derived network parcellations. A transition towards precision neuroscience will provide new avenues in the characterization of functional brain organization across development and within clinical populations.

Self‐Healing Functional Surfaces

AbstractDuring the last decade extensive research has focused on designing functional surfaces, e.g., with self‐cleaning, antibacterial, or antifouling properties, driven by the industrial demand on innovation and sustainability, and the academic interest in new functional materials. Such functionalities are strongly related with surface characteristics, namely chemical composition, physical properties, and topography. Surfaces are, however, dynamic and easily damaged resulting in reduced performance or immediate loss of the functionality. Damage is ubiquitous, hence incorporating self‐healing mechanisms allows repairing the functionalities while maintaining a high performance with extended service lifetime. Polymeric surfaces are particularly relevant for functional materials, covering the large majority of devices that are currently used. However, due to their chemical nature, they are typically soft and vulnerable to damages. This report covers the most recent advances concerning self‐healing functional surfaces. Low adherence polymeric surfaces are addressed. Further then recovering chemical composition only, additional challenges raised by the recovery of other surface features, such as roughness, porosity, or heterogeneity, are considered. The impact of inherent surface dynamics on the recovery of surface functionalities is discussed, the limitations are highlighted and alternatives are suggested. The recent progress on self‐healing of reversible and responsive surfaces is addressed and future research directions for self‐healing functional surfaces are anticipated.

Phosphonium Salts in Asymmetric Catalysis: A Journey in a Decade's Extensive Research Work

AbstractThe first report on a phosphonium salt as an asymmetric catalyst was published in 1997, and thereafter this area of research remained fairly dormant for almost a decade. However, the second decade (2007–2017) has recorded a significant growth in the published literature and it has now emerged as a hot topic of research. The use of phosphonium salts as a phase‐transfer catalyst has gained momentum in recent years due to their ease of availability and simple preparation technique. Most of these asymmetric phosphonium salts are derived from readily available starting materials like chiral amino acids and binaphthyl rings. With a simple modification in the basic core of these moieties, they can be used to execute a number of enantioselective organic transformations. This review presents a comprehensive overview of the historical development of catalyst design, with its necessary modification and applications in selective organic transformations.magnified image

Metallic Thin-Film Co- and Ce/Co-Coated Steels as Interconnect Material in IT-SOFC

In recent years SOFC manufacturers have been able to decrease the operating temperature significantly and today several anode- and metal-supported designs are able to operate at temperatures as low as 600-700 ˚C. One of several advantages of lower operating temperatures is the possibility to use less expensive materials, for example for the interconnect. Volatilization of Cr(VI) species and the increased electrical resistance, caused by the growing oxide scale, are probably the two most detrimental degradation mechanisms associated with the use of Cr2O3-forming ferritic stainless steels as interconnect material in SOFCs. Within the last decade extensive research has been carried out investigating these two degradation mechanisms. Development of custom-made alloys as well as reactive element surface treatments have been shown to improve corrosion resistance. Additionally a wide range of spinel based coating systems have been suggested to effectively mitigate Cr vaporization. However, the vast majority of studies, which investigate the mitigation of Cr vaporization in combination with oxide scale growth, and the electrical scale resistance were carried out at significantly higher temperatures (800-900 ˚C), often to accelerate the aforementioned degradation mechanisms. Cr vaporization, oxide scale growth, and electrical resistance are, however, all differently affected by a change in temperature, especially with regard to the influence of temperature on the microstructure of the oxide scale. In this work the effect of temperature in the technologically relevant temperature range (650-850 °C) is studied with focus on Cr vaporization, oxide scale growth, microstructural and chemical evolution, as well as the effect these factors have on the electrical resistance of the oxide scale (ASR). Commercially available interconnect materials such as Sanergy HT, Crofer 22 APU and AISI 441, coated with thin-film Co- and Ce/Co-coatings are exposed in air within a typical IT-SOFC temperature regime. Chromium vaporization is measured using the denuder technique, ASR is recorded ex-situ (after the furnace exposures) using platinum as electrode material and the oxide scales are characterized using SEM/EDX. The results from this work show that thin-film Co- and Ce/Co-coatings exhibit excellent properties as interconnect materials for IT-SOFC with respect to Cr vaporization, oxide scale growth, and electrical resistance. The results also show that temperature has a significant effect on the chemical composition of the oxidized Co-coating. However, due to the high electrical conductivity of the relevant Co-spinels, in comparison to the substantially lower electrical conductivity of chromia, this change does not affect the electrical resistance of the total oxide scale.

An ozone response relationship for four Phleum pratense genotypes based on modelling of the phytotoxic ozone dose (POD)

In the last decade extensive research has focused on the development of dose–response relationships based on stomatal plant ozone uptake (phytotoxic ozone dose, POD). So far most work has concentrated on crops and forest trees. This study provides a flux-based dose–response function for timothy (Phleum pratense), a widespread grassland species, which can be used in risk assessment for ground-level ozone. In 1996 and 2001 timothy was exposed in open-top chambers to ozone concentrations ranging from around 10nmolmol−1 in the charcoal filtered treatments up to 60nmolmol−1 in the fumigated treatments (08:00–20:00)in. In 1996 there was a negative effect of ozone on biomass production in the non-filtered treatment while in 2001 no such ozone effect in the non-filtered treatment could be seen. Measurements of stomatal conductance on four timothy genotypes in 2001 were used to calibrate a Jarvis-type multiplicative stomatal conductance model. The maximum conductance varied between the genotypes, from 477 to 589mmolO3m−2s−1 (projected leaf area). The model includes functions describing the reduction of stomatal conductance of senescing leaves and the direct effects on stomatal conductance by light, temperature and water vapour pressure deficit. A function describing ozone induced senescence of the leaves was included since exposure to ozone is known to cause premature senescence. The function for ozone was applied when it suggested ozone to be more limiting to stomatal conductance than phenology. To avoid overestimation of stomatal conductance in days with high VPD, a function reflecting the effect on leaf water potential on stomatal conductance was included. Comparison between modelled and measured conductance for the four timothy genotypes resulted in an r2 value at 0.57 and a very small average deviation of observed from modelled values. The calibrated stomatal conductance model was used to estimate the accumulated POD, i.e. the accumulated stomatal flux of ozone, of the plants in the 1996 and 2001 experiments. The strongest relationship between ozone relative effects on biomass was obtained when POD was accumulated from 105 degree days after emergence to 1000 degree days after emergence, and integrated using an uptake rate threshold of 7nmolm−2s−1 (POD7). The response relationship between biomass and POD7 resulted in an r2 value of 0.71 over all four genotypes. This r2 value was somewhat higher than for the corresponding relationship based on the accumulated ozone exposure over 40nmolmol−1 (AOT40; r2=0.66). With an uptake rate threshold at 7nmolm−2s−1, ozone concentrations above ∼20nmolmol−1, contribute to reduce the biomass production of timothy if meteorological conditions promote maximum stomatal conductance.

Osteoarthritis of the knee: current treatment options and future directions

Osteoarthritis (OA) is a slowly progressive, degenerating and disabling disease with a high prevalence in the adult population. This paper aims to provide an overview of current surgical and pharmaceutical intervention strategies, the benefits and burdens that come with each of these approaches and possible future directions for treatment of osteoarthritis of the knee. At present there is no convincing evidence that any treatment can slow down or prevent the development of OA. However, over the past decade extensive research has been done to elucidate the mechanism of OA development. Inflammatory cytokines appear to play an important role in this process and in vivo and in vitro studies have shown that directing intervention strategies at these factors is promising. Furthermore, a large number of dietary supplements have become available, but their effectiveness remains to be proven.

Neurotransmitter receptor variants and their influence on antipsychotic treatment (Review)).

Psychiatric treatment requires the use of drugs which are in many cases associated with severe side effects and inadequate response. In the past decade extensive research has investigated the link between gene alterations and treatment response and several strong associations have been reported. The identification of genes influencing treatment outcome will facilitate the pre-treatment selection of the most beneficial drug according to an individual's pharmacogenetic profile. Recent advances indicate that this goal is achievable in the near future. The scope of this communication is to review all the recent findings in psychopharmacogenetics leading to the individualization of treatment.

The male reproductive system and endurance exercise.

During the last decade extensive research on the role of exercise upon the human reproductive system has been conducted. Primarily these investigations have focused on female subjects, but an increasing number of studies have examined male related issues. Evidence now suggests that men who participate in chronic endurance training display mild degrees of reproductive system abnormalities. The major abnormalities noted thus far are reduced resting levels of testosterone, altered pituitary release of luteinizing hormone and prolactin, and altered sperm characteristics. The purpose of this article is to briefly review the research literature on this topic and address select aspects of the impact of exercise upon the male reproductive system. The principal topics addressed in this article are acute and chronic exercise effects, consequences of hormonal changes associated with endurance training, and potential mechanisms for the reproductive system changes detected.

PHARMACOTHERAPY OF OBSESSIVE‐COMPULSIVE DISORDER

SUMMARY Previously thought of as merely an interesting syndrome, obsessive‐compulsive disorder is now estimated to afflict 1%–2% of the world's population. Over the past decade extensive research into the epidemiology, aetiology, pathophysiology and pharmacological treatment of this condition has greatly improved its prognosis. This is largely due to the development of the serotonergic group of antidepressants, the selective serotonin reuptake inhibitors (SSRIs), which have consistently demonstrated antiobsessional properties. Monoamine oxidase inhibitors (MAOIs) and lithium have also contributed to the amelioration of symptoms in some patients. Other pharmacological treatment, often prescribed in combination with the SSRIs, include the antipsychotic drugs, benzodiazepines, and anticonvulsants.

ALUMINIUM-LITHIUM-COPPER-MAGNESIUM-ZIRCONIUM ALLOYS WITH HIGH STRENGTH AND HIGH TOUGHNESS - SOLVING THE PERCEIVED DICHOTOMY

Throughout the past decade extensive research and development has been carried out on aluminium-lithium base alloys because of the attractive combination of lower density and higher modulus that can be achieved in this system compared with conventional aluminium alloys. Much of this effort has been directed at understanding and overcoming their Achilles heel of low ductility and poor fracture toughness (particularly for crack planes perpendicular to the short transverse direction). This study reviews the metallurgical features which affect ductility and damage tolerance in the 8090 and 8091 alloys developed at Alcan and the Royal Aircraft Establishment. The paper shows that control of these metallurgical features can be used to markedly improve these properties. Three examples will be given. In the first case the production of material with a high damage tolerance will be discussed. It will be shown that by control of grain structure and ageing practice, 8090 sheet with a plane stress fracture toughness (Kc) of >130 MPa/[MATH] can be achieved at similar strength levels to 2024-T3 sheet. There is also a decrease in fatigue crack growth rate. This results in sheet with an overall damage tolerance capability comparable with that of 2024-T3. The other examples concern the processing of 8090 and 8091 plate to meet medium and high strength airframe requirements respectively. 8090 plate (<100 mm thick) can achieve the property requirements of 7010-T7651, with short transverse ductilities in excess of 3% and short transverse fracture toughness of 218 MPa/[MATH]. This is accomplished by controlled thermomechanical treatment. Similar treatments applied to the 8091 alloy result in a material competitive with 7150-T651 for specific apflications (e.g.upper wing skins, where short transverse performance is sacrificed in favour of in-plane properties).

Genetic alteration in animal cells in culture.

In the past decade extensive research has been addressed to inducing, selecting, and analyzing specific heritable phenotypic alterations of mammalian cells in culture. The vast literature which has resulted from these efforts has been reviewed on several occasions. The earlier monographs of the nascent discipline could be encyclopedic (De Mars 1971; Thompson and Baker 1973), while some of the more recent treatments ofmammalian cell genetics have been highly specialized and even analytic (e.g. Siminovitch 1976; Basilico 1977; Bakerand Ling1978).Here we will attempt to mark entrance into the “second generation” of somatic cell genetics as characterized by a number of gene transfer techniques and also emphasize very limited specific areas that have not been rigorously discussed previously.