Diversity in pathway recruitment for memory processing

OBJECTIVE: Aim of the modern oncological neurosurgery is to maximize the extent of tumor resection, with a parallel minimization of postoperative neurological deficits; therefore, localization of “eloquent” cortex is essential. Intraoperative Electrical Stimulation (IES) during awake craniotomy is considered the “gold standard” for functional mapping in tumor surgery. In this report we present our preliminary results from a 30-patients series that underwent awake craniotomy. MATERIAL-METHOD: During a 2.5-years period, glioma patients (22 left /8 right hemisphere) underwent awake craniotomy for tumor excision. Bipolar IES conducted with the following parameters: amplitude ranged from 2mA to 6mA, frequency was set at 60 Hz, spatial diameter of stimulation was 0.5mm and the time of stimulation was 1-2 for motor and 4-5 seconds for cognitive-language mapping. Motor and language responses detected through motor and language naming tasks, conducted by a neuropsychologist thought out the operation. RESULTS: Negative motor (upper/lower limbs, tongue arrest, oculomotor apraxia), positive motor (upper limb, fingers, face twitches) and positive sensory (paresthesias) responses were elicited when stimulating premotor areas, primary motor and somatosensory cortex respectively. Speech arrest, phonemic, semantic and anomic errors, and perseverations were produced when left frontal, temporal and inferior parietal lobule areas were stimulated at cortical and subcortical level. Immediate post-operative assessment showed functional deterioration in 50% of patients; 3 months postoperatively all patients but 2 reached their preoperative status. CONCLUSIONS: Awake craniotomy allows resection of tumors in eloquent areas with an acceptable risk of permanent postoperative deficit and should be performed in cooperation with expert clinical neuropsychologists.

knowledge base that the individual is endowed with, and which can grow by the influence of culture. This component does not show decline until very old age. The ‘mechanics’ component is the means to gain knowledge, while ‘pragmatics’ component is the abstract knowledge gained, or that is being 'crystallized'. Evidence for this two-component model comes from multiple sources (see Baltes et al., 2006; p. 598600.), including longitudinal studies (e.g. Seattle Longitudinal Study) indicating that cognitive abilities related with the ‘mechanic’ component (i.e. reasoning, memory, perceptual speed, spatial orientation) follow a nearly linear decline throughout adulthood, while cognitive abilities related with the ‘pragmatics’ component (i.e. verbal ability, numeric ability) does not show decline until very old age (see Figure 1). Figure 1 Cross-sectional data from the Seattle Longitudinal Study (image from Hedden & Gabrieli, 2004) Causes of Age-Related Changes in Cognition In this section different approaches to explain age-related changes in cognition will be outlined, along with empirical findings. The first of these is the 'general slowing' hypothesis, which mainly explains age-related changes in intellectual fluid abilities as a 9 function of a general slowing of processes (T. Salthouse, 1996). According to this theory, the slowing down of executing processes leads to impaired cognitive performance in most cognitive tasks. While the general slowing hypothesis is still an integral theory for explaining age-related decline in many areas, it is not adequate to explain age-differences in conditions with high cognitive control demands (Mayr & Kliegl, 1993; Verhaeghen, Steitz, Sliwinski, & Cerella, 2003). Age-related changes in intellectual abilities can also be explained as a function of changes in inhibitory processes. An early study (Kramer, Humphrey, Larish, & Logan, 1994) for instance, found little evidence for age-related deficits in inhibitory processes, however older adults had more difficulty than younger adults to abort an action (in a stop signal paradigm where participants are asked to respond to a visual stimuli unless they hear an auditory signal), and it also proved more difficult for older adults to learn new rules in a categorization task. Also, comparing younger and older adults, inhibition related processes were found to be delayed in the elderly as evidenced by delayed inhibition-related ERPs (event related potentials, recorded with electroencephalogram) (Falkenstein, Hoormann, & Hohnsbein, 2002). It is also possible to attribute age-related differences in intellectual abilities to changes in working-memory performance. Recent studies have demonstrated that older adults show deficits in suppressing task-irrelevant information during working-memory performance whereas their ability to enhance task-relevant information is intact (Gazzaley, Cooney, Rissman, & D’Esposito, 2005). Furthermore, it has been shown that an interruption during task maintenance distracts both younger and older adults, however while younger adults quickly disengage from the task-irrelevant disruptor and reestablish task-relevant functional networks, older adults are impaired in dynamic shifting between competing representations (Clapp, Rubens, Sabharwal, & Gazzaley, 2011). Similar 10 findings came also from a study employing an inhibition of return paradigm (Wascher, Falkenstein, & Wild-Wall, 2011) and another study using a dual task paradigm (Hahn, Wild-Wall, & Falkenstein, 2011) suggesting that older adults process irrelevant information similarly as relevant information, and this leads to impairments in workingmemory performance. We can also approach to explain age-related differences in intellectual abilities in terms of biological changes in the nervous system. Some decades ago large scale general neuron loss was suggested to be the main reason for age-related cognitive decline (Ball, 1977; Coleman & Flood, 1987). However, recently it became evident that general neuron loss in most areas does not contribute significantly to age-related cognitive decline (Burke & Barnes, 2006) but rather there are specific areas such as the prefrontal cortex (PFC) in which neuron loss is related to cognitive decline. A study, for example, with aged monkeys have found an approximately 30 percent reduction of neurons compared to younger animals in the dorsolateral PFC area 8A, and this reduction correlated with impaired performance in a working-memory task, but at the same time other areas related to working-memory (such as area 46) were well preserved (Smith, Rapp, McKay, Roberts, & Tuszynski, 2004). Less age-related change has been reported for many electrophysiological properties of neurons in the hippocampus and the PFC, such as resting membrane potential, membrane time constant, threshold to elicit an action potential, and rise time and duration of an action potential (Burke & Barnes, 2006). However, reduced synapse number in older animals might be related with cognitive decline. It has been found in rats, that synapse number per neuron diminishes during aging in the dentate gyrus, which is a hippocampal sub-region that is important in spatial memory (Geinisman, Toledo-Morrell, & Morrell, 1986).

Over the past several decades, extreme drought events have become increasingly frequent in Central Serbia and have affected vast areas of land. In agriculture, the impact of drought is dramatic, especially if the soils in the affected area are shallow, like in most of the Sumadija Region where field crops, fruits and grapevines are traditionally rainfed. Exceptionally dry years have a multiple-year effect. Investment in irrigation is imminent but not feasible without state subsidies. To arrive at an impartial decision as to which part of a region should be given priority, it is extremely important to study the spatial distribution and severity of drought. Assessments made to date have resulted in the identification of areas with similar precipitation patterns. However, these assessments are rather crude and have classified parts of Serbia by precipitation depth or climatological precipitation deficit; as such, they are not accurate enough for agricultural purposes. Present-day needs call for more detailed analyses on a smaller scale for specific purposes such as plant production. It is a well-known fact that drought does not simultaneously affect an entire region. It is generally more severe in a certain area, less severe in another area, and may leave parts of the region unaffected. The objective of this research was to conduct a statistical analysis to determine the homogeneity of drought within a region, in spatial and temporal terms. Towards that end, the Standardized Precipitation Index (SPI) of the growing season was studied in 12 areas over a monitoring period of 60 years. Applying the Principle Component Analysis (PCA) method, a single dominant component with a total variance of 69.47% was determined, to which all sites contributed equally. Varimax rotation was then applied and resulted in the identification of three areas. Based on this study of the spatial distribution of drought in the considered region, only one area to the east could be reliably identified as experiencing neither extreme drought nor excessive moisture, while no such claim could be made about two other areas which were assessed. Consequently, drought mitigation measures may be based on separate, homogeneous units. Key words: Agricultural drought, principal component analysis (PCA), standardize precipitation index (SPI).

The late Cambrian–Early Ordovician siliciclastic sequence in central northern Tasmania represents an excellent case study to document the transition from an active rifting succession to a post-rift system. Initial rifting created a complex system of half-graben, providing accommodation space for large volumes of basement-derived material. These half-graben were initially filled with coarse-grained alluvial fan sediments and a thick, syn-rift, low-sinuosity, multiple-channel braided fluvial succession. The uppermost sequence comprises a post-rift, regional, shallow marine, transgressive sandstone and mudstone package. <br> <br> Six broad lithofacies have been recognised in the late Cambrian–Early Ordovician siliciclastic sequence: Four lithofacies are interpreted to represent terrestrial alluvial fan (displaying debris flow, sheet-flow and channel-flow geometries) and braided fluvial deposits (transitioning between proximal and distal sedimentological characteristics upsection), while two represent marginal-marine (tidal) to shallow marine environments (dominated by heterolithic bedding, and varying degrees and styles of bioturbation). Adjacent lithofacies often display marked lateral variations in both thickness and grain-size, suggesting accelerated changes in the volume of sediment flux and/or the rate of tectonic subsidence, particularly of the basal, coarse-grained, conglomerate-rich sequences where the varying composition and texture suggests considerable relief on hinterland palaeotopography. <br> <br> A revised stratigraphic framework for the late Cambrian–Early Ordovician siliciclastics of central northern Tasmania is presented based on lithofacies and lithofacies associations. The Roland Formation forms the lower stratigraphic unit and comprises generally fining-up, conglomerate-dominated alluvial fan and proximal, low-sinuosity, multiple-channel braided river successions associated with syn-rift sedimentation. A hiatus in the extensional tectonics is recorded by a regionally extensive unconformity between the Roland Formation and the overlying Moina Formation, named the intra-Owen Group Unconformity. The Moina Formation marks a transition from high energy, terrestrial, conglomerate-rich sequences of the Roland Formation, to more moderate energy sandstone-dominated sequences that typically display an increasing marine signature towards the top of the unit. Three distinct sedimentary successions are recognised within the Moina Formation, and member status has been given to each of these since the distribution and relationships between these stratal packages is fundamental in understanding the mature phase of the late Cambrian–Early Ordovician extensional event, and the post-rift transgressive system. The terrestrial braided fluvial, channelised sandstone and minor conglomerate of the Badgers Range Member are superseded by interbedded, fine- to medium-grained sandstone deposited in a tidal regime (Deloraine Member) that is in turn overlain by thinly bedded, heavily bioturbated, shallow marine mudstone and fine-grained sandstone (Caroline Creek Member). <br> <br> Sedimentological principles, including provenance studies and palaeocurrent analysis, are used to document the basin configuration and structural framework of the rift system. The spatial and temporal migration of depocentres can be documented such as in the Badgers Range where two fining-up successions are separated by the intra-Owen Group Unconformity with the lower quartzite-dominated Roland Formation being succeeded by the chert lithic-rich Moina Formation. It is apparent that depocentres were compartmentalised by topographic highs, and the sedimentary fill of these depocentres reflects the lithological composition of these highs. In addition, the observed general decrease in grain-size is not uniform, and there are numerous changes in sedimentation as a consequence of fluxes in uplift and subsidence in the source and basinal areas. <br> <br> The distribution of thickly-bedded, coarse-grained conglomerate sequences, the juxtaposition of differing lithological successions, and the construction of geological cross-sections give insights to the location and position of several major bounding faults. These faults were subsequently reactivated during the Early–Middle Devonian Tabberabberan Orogeny, and a significant amount of reverse movement is recorded on the basis of structural restorations. <br> <br> Regional palaeogeographic reconstructions of the Early Ordovician (Tremadocian; 480 Ma) (Cocks, 2001) demonstrate that Tasmania was located outboard of the eastern margin of Gondwana, situated north of the palaeoequator between latitudes 10° and 20°. The late Cambrian through Ordovician tropical climate was dominated by the influence of a strong, extended greenhouse effect. The lack of sediment stabilisation by plants and rootlets in this Early Palaeozoic, vegetation-free, terrestrial landscape resulted in alluvial and fluvial depositional processes being markedly different from their present day counterparts, since vegetation exerts significant influence on a variety of environmental factors. In particular, energy levels and run-off rates would have been greater, fluctuations in energy levels more extreme, and high energy events more frequent. These conditions would likely have been amplified by the relatively high precipitation rates associated with the tropical palaeogeographic position of Tasmania. Likewise, wind processes would have played a far greater role than present with regards to the removal of clay- and silt-sized particles from the depositional setting, and this may explain the paucity of claystone and siltstone in these terrestrial environments.

Studies Reveal Rx for Doctors: A Daily Dose of Meditation

Electron Beam Induced Deposition (EBID) allows deposition of three-dimensional micro- and nano-structures of conductive and insulating materials on a wide range of substrates. The process is based on the decomposition of molecules of a pre-selected precursor by a focused electron beam. In recent decades EBID of several metals, namely Au, W, Cu and Pt, from different families of precursors, has been achieved and the technique has found some application for small-scale production of laboratory devices and for repair of masks and micro-optoelectronic devices. The weak point of the technique is at present the low purity of the deposited material, caused by metal-organic precursors and by the lack of selectivity of the electron-induced decomposition process. This work is dedicated to EBID of Rh nanostructures from the precursor [RhCl(PF3)2]2. High metal content deposits are expected because the precursor does not contain C atoms and because Rh is one of the less reactive metals. [RhCl(PF3)2]2 as EBID precursor has been characterized by vapor pressure, mass spectrometry and surface residence time measurements. The vapor pressure of 7.5 Pa at room temperature reveals that the precursor is sufficiently volatile for room temperature EBID. The knowledge of the vapor pressure allows also to estimate the number of precursor molecules delivered to the reaction area per unit time. Mass spectrometry measurements allow to know the decomposition path of the precursor under electron impact in the gas phase. The measured spectrum indicates that the molecule decomposes by successive loss of PF3 groups, as confirmed by density functional theory calculations. This is compatible with a high metal content deposit. Residence time measurements show that [RhCl(PF3)2]2 does not decompose on stainless steel surfaces. The measured residence time of 2 ms allows to estimate that the activation energy for desorption of [RhCl(PF3)2]2 on stainless steel is about 0.6 eV and that precursor molecules can travel distances in the micrometer range before being desorbed. EBID structures obtained from [RhCl(PF3)2]2 have been characterized with a wide range of techniques for a better knowledge of the material properties and the deposition process. The deposit morphology has been studied by Transmisssion Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) to characterize the different steps of the deposition process. Crystallographic analysis is carried out by TEM in diffraction mode. Chemical analysis is carried out by Auger Electron Spectroscopy (AES) and Electron Energy Loss Spectroscopy (EELS). Morphological analysis of deposits carried out at different exposure times reveals that the first phase of the growth process, in close proximity to the substrate, is characterized by an increase of the deposit height and the deposit diameter. On the other hand the second phase of the growth process is characterized by increasing height and constant diameter. TEM contrast profiles of dots and Atomic Force Microscopy (AFM) sections of lines have clearly shown that the EBID rate is highest in the center of the beam and decreases in the peripheral regions. Deposition at variable distances from the precursor source allowed to obtain hollow structures, whose morphology reveals that the precursor reaches the reaction area mainly by direct gas phase transport. Structural analysis and TEM revealed that, independently of the deposition conditions, the deposited material is made up of Rh nanocrystals immersed in a lighter amorphous matrix. Chemical analysis by Auger Electron Spectroscopy revealed that, after removal of the C rich contamination layer by Ar ion sputtering, the average composition of the deposits is about: 60 at.% Rh, 20 at.% P, 5 at.% Cl, 7 at.% N, 8 at.% O. The absence of C and the presence of N and O in the deposit bulk have been confirmed by Electron Energy Loss Spectroscopy. This technique allowed also to prove that Rh is dominant also in deposits of sub-micrometer size (not analyzable with AES) and to determine the elemental distribution in the deposit with nanometer resolution. Comparison of the deposit composition and the positive ions detected by mass spectrometry revealed that EBID, compared to low pressure gas phase ionization, involves a higher number of events, i.e. multi-electron decomposition and rearrangements of partially decomposed species.

THE ROLE OF INHIBITORY INTERNEURONS IN A MODEL OF DEVELOPMENTAL EPILEPSY By Patrick James Wolfgang, M.S. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Anatomy and Neural Biology at Virginia Commonwealth University. Virginia Commonwealth University, 2007 Major Director: Kimberle Jacobs Assistant Professor Department of Anatomy and Neurobiology Epilepsy, defined by recurrent seizures, is the one of the most prevalent neurological disorders worldwide (World Health Organization 2007). While many forms of epilepsy are well-controlled by anti-epileptogenic medications, a significant portion of patients have intractable, i.e. untreatable, seizures. The etiology of these seizures is varied, but a significant cause, particularly for patients with intractable epilepsy is developmental malformation. In these cases, an error or interruption during the development of the neocortex produces a structural alteration. Such patients may have other neurological problems, but seizures are the most common symptom. The neuronal mechanisms that link malformation and cortical hyperexcitability are not well understood. Here we have ix sought to examine potential mechanisms that result from microgyria, a malformation characterized by excessive numbers of small gyri. The presence of epileptiform activity indicates that the normal balance of excitation and inhibition has shifted . Two functions of inhibition within neocortex are to prevent spread of excitation, and to modulate the timing of surrounding excitation. Although seemingly contradictory, increasing some forms of inhibition can result in an increase in synchronous excitatory activity. We hypothesize that for certain malformation epilepsies, the inhibitory processes that control timing are increased, creating a hyper-synchronous cortex, while the inhibitory processes that control horizontal spread are decreased, allowing the propagation of such activity. Here we have examined the network effect of selectively modulating the inhibitory cells that control vertical or columnar cortical synchrony. This modulation is performed via activation of metabotropic glutamate receptors found on the verticallyprojecting interneurons but not on those inhibitory cells that control horizontal spread of activity. Our results suggest that the network effect of activating these interneurons is altered in malformed, epileptogenic cortex.

The prefrontal cortex (PFC), which mediates the emotional coping response to different stressful paradigms, is composed of distinct parts depends on stimulus involved physical or psychological stress. It also plays a role in a number of neurological conditions. It`s known that neuroendocrine control of homeostatic and reproductive functions including stress response and energy metabolism is fulfils by important signaling molecules as endogenous cannabinoids. The aim of the present study was to examine the effects of cold stress on distribution of CB1- receptors in PFC of rats. Immunohistochemical procedure for CB1-receptors was performed in adult male Wistar rats. The data were entered in the computer program, recorded automatically, calculated and compared by Student`s t-test. We found CB1-immunoreaction in axons and dendrites as well as in cell bodies where they presented as puncta on somata. The cells bodies were comprised of several distinct shapes: pyramidal, oval, fusiform and multipolar. Numerous fine-beaded fibers and puncta were seen on a handful of pyramidal large-sized neurons and many puncta were observed around the oval-shaped small- and medium-sized neurons.The PFC in cold stress rats demonstrated around 18% higher density of CB1-receptors compared with controls. In conclusion our results showed that cold stress exposure increased distribution of CB1-receptors in PFC of rats. These experimental data suggest that endocannabinoid system in this brain area may play an important role in the continuity of homeostasis in cold stress.

The human brain connectome is a new and rapidly developing project in neuroscience. The pattern of structural and functional connectivity in the brain is not fixed, but is continuously changing in response to experiences. Ex­ploring these phenomena opens a powerful arsenal of analyses and computational approaches that could provide important new insights into clinical and cognitive neuroscience. The aim of the present study was to investigate the structural plasticity of the cortical areas of the brain during a memory task performance using functional MRI. Fifteen right-handed male subjects and fourteen right-handed female subjects were scanned during memory par­adigm performance. The scanning of the participants was performed with a 3Т MRI system - GE Discovery 750 w with a protocol including structural scan - Sag 3D T1 F-BRAVO FSPGR, slice thickness 1 mm, matrix 256N…256, flip angle 10о and standard block design functional scan - 2D EPI, slice thickness 3 mm, matrix 64N…64, TR (rep­etition time) - 3000 msec, TE (echo time) -30, flip angle 90о. Data were analysed using the SPM 12 (Statistical Paramertic Mapping) software running on MATLAB R2015 for Windows. The level of statistical significance was set at P < 0.05. Statistical significance in brain cortical activation was not found between males and females. We found reliable occipital and temporal signal response across the block design contrasts with statistically significant differenc­es within the groups in both genders. The results highlighted several detailed differences between males and fe­males and potential future directions in brain activation studies.

Natural and Anthropogenic Drivers of Water Quality in the Normanby Basin and Princess Charlotte Bay, Cape York Peninsula, Australia

شناخت آسیب پذیری جمعیت و گروه های انسانی به عنوان اقدامی ابزاری در راستای پیشگیری از زایش فاجعه مبتنی بر زیستن در نواحی پر خطر مطرح است. تحلیل آسیب پذیری کانون‌های جمعیتی واقع در عرصه های خطر اقدامی علمی برای فراهم سازی زیر ساخت اطلاعاتی مناسب از درجه و میزان خطرپذیری از رخداد مخاطره است. بر اساس چنین دیدگاهی مسئله تحلیل آسیب پذیری ناشی از مخاطرات ژئومورفولوژیک فرونشست در جنوب شهر تهران مورد توجه قرار گرفته است. بدین منظور در ابتدا با استفاده از تکنیک تداخل سنجی راداری نرخ و دامنه فرونشست در محدوده مورد مطالعه استخراج گردید. سپس برای تولید نقشه فضایی عرصه های پر مخاطره نرخ و دامنه فرونشست به عنوان فاکتور عامل در زایش مخاطره به تحلیل گر سیستم در محیط GIS وارد گردید. نقشه خروجی معرف سلول‌های واجد ارزش متفاوت از فاکتور زایش مخاطره است. استخراج عرصه متعلق پهنه در معرض مخاطره نشان داد که از مجموع مساحت محدوده 7/12 درصد در پهنه های بسیار پرخطر، 7/14 در عرصه پرخطر،5/15 در عرصه نسبتاً پرخطر بیش از نیمی از محدوده (57درصد) در عرصه نسبتاً کم خطر قرار گرفته‌اند. برای ارزیابی میزان خطرپذیری، الگوی توزیع فضایی تأسیسات و ساخت‌وساز های موجود با نقشه عرصه های در معرض خطر هم نهاد گردید. مبتنی بر این اطلاعات و با استفاده از پیمایش میدانی اقدام به بررسی آسیب پذیری جمعیت ،مساکن و تأسیسات موجود در محدوده مورد مطالعه صورت پذیرفت. یافته های تحقیق موید آسیب پذیر بودن اکثر سکونت گاه‌ها و جمعیت ساکن درآنهاو تأسیسات موجود در محدوده می‌باشد. همچنین بر اساس پایش های میدانی صورت گرفته مشخص گردید که اکثر ساخت و سازهای موجود در منطقه غیر اصولی بوده که این امر باعث فراهم آوری زیرساخت آسیب پذیری برای مستحدثات در شرایط خطرپذیر است.

Motor intention in the posterior parietal cortex

This study was carried out on all the Etna beech distribution area and consists of a phytosociological analysis. Moreover data relating to various pysiognomical and structural aspects was collected from 12 sample areas selected on the different expositions of the volcano. From the phytosociological analysis it emerged that it is very difficult to define the Etna beech forests syntaxonomically: in most cases it can be seen that they belong to the class Querco-Fagetea, but it is not always possible to identify the association, the alliance and the order. Some communities seem to belong to the Quercetalia pubescentis rather than to the Fagetalia sylvaticae. Other communities do not even belong to the class Querco-Fagetea. These are in fact relict forests surviving in extreme life conditions. They are at the southern limit of its distribution area and are subject to unfavorable environmental conditions: a volcanic substrata, the Mediterranean climate, the high level of man&amp;rsquo;s intervention. The study of the tree and stump density, stem diameter, basal area, litter cover and litter thickness and seedling density, carried out on 12 sample areas, shows that these forests have a very variable physiognomy and structure. The forests with a more balanced physiognomy and structure are made up of forests with high trunks of different ages. The seedling density, correlated with the litter thickness and cover, was found to be significant in areas located on the east side of Etna, where there are better light conditions and greater rainfall. This study brought to light the presence of a species: Monotropa hypopytis L. not previously reported as having been found on Mt. Etna.

Adolescent growth provides a unique opportunity for the growing body to adapt to external stimuli. A positive association between site-specific mechanical loading and increases in regional bone mineral content (BMC) during adolescence is established. Mechanical loads associated with middle-distance running expose the skeleton to a combination of compressive ground reaction forces and muscular contraction. Previous studies concerning musculoskeletal health in active adolescents are largely limited to planar, two-dimensional measures of bone mineral status, using Dual X-ray Absorptiometry (DXA). Intrinsic bone material properties are accurately measured using DXA. However, the interaction between bone material and structural properties that reflects the mechanical integrity of bone require a combination of imaging modalities. Magnetic Resonance Imaging (MRI) provides a three-dimensional geometric and biomechanical assessment of bone. When MRI is integrated with DXA technology, an effective non-invasive method of assessing in vivo bone strength is achieved. The impact of high training volumes on musculoskeletal development of male and female adolescent athletes engaged in repetitive, high magnitude mechanical loading has not been investigated. Specifically, differences in total body and regional bone mineral, bone and muscle geometry, bone biomechanical indices and bone strength at differentially-loaded skeletal sites have not been compared between adolescent middle-distance runners and age- and gender-matched non-athletic controls.;Objectives: (i) to investigate the effects of intense sports participation involving mechanical loading patterns on bone mineral, bone and muscle geometry, biomechanical indices and estimated regional bone strength between elite adolescent male and female middle-distance runners and age- and gender-matched controls (ii) to examine factors predictive of total body BMC, distal tibial bone geometry, distal tibial bone strength, and Hip Strength Analysis (HSA)- derived indicators of bone strength at the femoral neck. Methods: Four groups of 20 adolescents were comprised of male (mean (SD) age 16.8 REPLACE2 0.6 yr, physical activity 14.1 REPLACE2 5.7 hr.wk-1) and female (age 16 REPLACE2 1.7 yr, physical activity 8.9 REPLACE2 2.1 hr.wk-1) middle-distance runners, and male (16.4 REPLACE2 0.7 yr, physical activity 2.2 REPLACE2 0.7 hr.wk-1) and female (age 16 REPLACE2 1.8 yr, physical activity 2.0 REPLACE2 0.07 hr.wk-1) controls. Total body and regional BMC were calculated using DXA. Distal tibial bone and muscle cross-sectional areas (CSA) were assessed using MRI. To calculate distal tibial bone strength index (BSI), a region of interest representing 10% of the mid distal tibia was analysed for DXA-derived bone mineral and was combined with bone geometry and biomechanical properties from MRI assessments. Calculations for femoral neck strength were acquired from DXA-derived HSA software. Results: No differences were found between male athletes and controls for unadjusted BMC at total body or regional sites. After covarying for fat mass (kg), male athletes displayed greater BMC at the lumbar spine (p = 0.001), dominant proximal femur (p = 0.001) and dominant leg (p = 0.03) than male controls. No differences were found in distal tibial bone geometry, bone strength at the distal tibia or HSA-derived indicators of bone strength at the femoral neck between male athletes and controls.;Lean tissue mass and fat mass were the strongest predictors of total body BMC (R2 = 0.71), total muscle CSA explained 43.5% of variance in BSI at the distal tibia, and femur length and neck of femur CSA explained 33.4% of variance at the femoral neck. In females, athletes displayed greater unadjusted BMC at the proximal femur (+3.9 REPLACE21.4 g, p = 0.01), dominant femoral neck (+0.5 REPLACE2 0.12 g, p = 0.01) and dominant tibia (+4.1 REPLACE2 2.1 g, p = 0.05) than female controls. After covarying for fat mass (kg), female athletes displayed greater (p = 0.001) total body, dominant proximal femur and dominant leg BMC than female controls. Female athletes also showed greater distal tibial cortical CSA (+30.9 REPLACE2 9.5 mm2, p = 0.003), total muscle (+240.2 REPLACE2 86.4 mm2, p = 0.03) and extensor muscle (+46.9 REPLACE219.5 mm2, p = 0.02) CSA, smaller medullary cavity (-32.3 REPLACE2 14.7 mm2, p = 0.03) CSA and greater BSI at the distal tibia (+28037 REPLACE2 8214.7 g/cm3.mm4, p = 0.002) than female controls. Lean tissue mass and fat mass were the strongest predictors of total body BMC (R2 = 65), hours of physical weekly activity and total muscle CSA explained 58.3% of the variance of distal tibial BSI, and neck of femur CSA accounted for 64.6% of the variance in a marker of femoral neck HSA. Conclusion: High training loads are associated with positive musculoskeletal outcomes in adolescent middle-distance runners compared to non-athletic controls. Exposure to similar high training loads may advantage female adolescent athletes, more than male adolescent athletes compared with less active peers in bone strength at the distal tibia.

The European Union Reference Laboratory for Genetically Modified Food and Feed (EU-RL GMFF), accredited under ISO/IEC 17043, organised a comparative testing (CT) round for National Reference Laboratories (NRLs) nominated under Regulation (EC) No 882/2004, with voluntary participation of other official control laboratories.\nThe test items consisted of rice noodles and commercial soybeans spiked with ground powder of soybean event DP-356043-5 in two different concentrations (Level 1 and 2). Participants were required to perform species identification and test for the presence of any GM event in the two test items. Any event detected then had to be quantified. Participants could report the results in mass/mass % or copy/copy % and the EU-RL GMFF calculated the robust means (R) for Level 1 and 2 test items accordingly. The target standard deviation for CT was fixed by the Advisory Board for Comparative Testing at 0.2 for the event, based on the experience of previous CT rounds. The robust means and target standard deviation were used to derive z-scores for the participants’ results. \nEighty-eight laboratories from 42 countries registered for this CT round, of which 85 laboratories from 41 countries returned at least qualitative test results. \nWhen performing species identification, almost all laboratories correctly identified soybean and rice in both test items, and a few laboratories also detected maize and/or oilseed rape. In total 71 laboratories reported the presence of GM material in the test items, but 14 laboratories failed in this task. All of the 71 laboratories, except eight, correctly identified soybean event DP-356043-5 in the test items.\nResults of the quantitative evaluation of the GM content were satisfactory for both measurement units, with only two NRLs appointed under Regulation (EC) No 1981/2006 (one measuring in m/m % and one in cp/cp %) obtaining unsatisfactory z-scores (|z| ≥ 2.0) for both test items. \nDespite the overall satisfactory outcome of this CT round, only 58 % of participants provided information on measurement uncertainty in a complete and consistent manner, and further improvement in this crucial area is needed.