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Realistic human head models are of great interest in traumatic brain injury research and in the forensic pathology courtroom and teaching. Due to a lack of biomechanical data, the human dura mater is underrepresented in head models. This study provides tensile data of 73 fresh human cranial dura mater samples retrieved from an area between the anterior middle and the posterior middle meningeal artery. Tissues were adapted to their native water content using the osmotic stress technique. Tensile tests were conducted under quasi-static uniaxial testing conditions with simultaneous digital image correlation. Human temporal dura mater is mechanically highly variable with regards to its elastic modulus of 70 ± 44 MPa, tensile strength of 7 ± 4 MPa, and maximum strain of 11 ± 3 percent. Mechanical properties of the dura mater did not vary significantly between side nor sex and decreased with the age of the cadaver. Both elastic modulus and tensile strength appear to have constant mechanical parameters within the first 139 hours post mortem. The mechanical properties provided by this study can help to improve computational and physical human head models. These properties under quasi-static conditions do not require adjustments for side nor sex, whereas adjustments of tensile properties accompanied with normal aging may be of interest.

Thyroid hormones (TH) are essential for brain development, and their synthesis is dependent on thyroperoxidase activity in the thyroid follicles. The U.S. Environmental Protection Agency’s ToxCast program has identified a number of environmental chemicals that are thyroperoxidase inhibitors in vitro and therefore potential thyroid hormone system disruptors. However, what effects these chemicals can have on in vivo serum TH concentrations or on brain development remain unknown. Here, we exposed pregnant rat dams by oral gavage to 2-mercaptobenzimidazole (MBI), amitrole or cyanamide; three environmental chemicals that are in vitro inhibitors of thyroperoxidase. MBI and cyanamide had only minor, sporadic effects on TH concentrations in dams but caused reproductive toxicity such as dystocia and reduced postnatal body weights. In contrast, amitrole, a triazole pesticide, reduced circulating thyroxine (T4) concentrations and caused abnormal brain development in the offspring. A congenital malformation were observed in the brain of the offspring, with large clusters of ectopic neurons in the corpus callosum; so called periventricular heterotopia, which can form after developmental TH insufficiency. Since the irreversibly formed heterotopia appears to manifest after exposure to amitrole, this pesticide joins the two classical thyroperoxidase inhibiting anti-thyroid drugs propylthiouracil and methimazole. We propose heterotopia formation as a relevant effect endpoint for developmental thyroid hormone system disruption caused by exposure to thyroperoxidase inhibiting chemicals.

Orthopedic surgeons endure high physical stresses when performing surgery, as large forces and torques are applied commonly. Occupational risks are consequently higher when compared to other surgical disciplines. One example is the reaming of the acetabula during total hip arthroplasty, using customized instruments. This surgery may predispose the surgeon to overuse-related wrist pathology. In this study, torques acting along the reaming tool were measured, and the resulting forces applied to the orthopedic surgeons' wrists were estimated based on the measured torque data from hip reaming. Different reamer sizes and tool velocities were analyzed to determine how both parameters may influence the torques applied at the surgeon's wrist. Using a highly standardized setup, torques were measured while the reamer was pushed into the acetabula to remove cartilage. Maximum torques and stoppage torques at blocking of the reamer were compared between feed rates and reamer sizes. Peak values of the maximum torques along the reamer axis averaged 1.5-1.8 Nm. No significant difference between maximum torques and reamer sizes was found. A significant difference in maximum torques was noted between feed rates with a large effect (p = 0.010; i2 = 0.214) and a large interaction effect (p = 0.017; i2 = 0.186). Based on this experimental setup, it can be hypothesized that the impulsive behavior of the torque when the milling tool reaches the subchondral lamella could potentially contribute to wrist pathology. These preliminary data warrant further study. Consequently, torque limiters should be implemented in reamers to minimize the risk of occupation-related pathology to the wrist.

Under the Paris Agreement (PA), progress of emission reduction efforts is tracked on the basis of regular updates to national greenhouse gas (GHG) inventories, referred to as bottom-up estimates. However, only top-down atmospheric measurements can provide observation-based evidence of emission trends. Today, there is no internationally agreed, operational capacity to monitor anthropogenic GHG emission trends using atmospheric measurements to complement national bottom-up inventories. The European Commission (EC), the European Space Agency, the European Centre for Medium-Range Weather Forecasts, the European Organisation for the Exploitation of Meteorological Satellites, and international experts are joining forces to develop such an operational capacity for monitoring anthropogenic CO2 emissions as a new CO2 service under the EC’s Copernicus program. Design studies have been used to translate identified needs into defined requirements and functionalities of this anthropogenic CO2 emissions Monitoring and Verification Support (CO2MVS) capacity. It adopts a holistic view and includes components such as atmospheric spaceborne and in situ measurements, bottom-up CO2 emission maps, improved modeling of the carbon cycle, an operational data-assimilation system integrating top-down and bottom-up information, and a policy-relevant decision support tool. The CO2MVS capacity with operational capabilities by 2026 is expected to visualize regular updates of global CO2 emissions, likely at 0.05° x 0.05°. This will complement the PA’s enhanced transparency framework, providing actionable information on anthropogenic CO2 emissions that are the main driver of climate change. This information will be available to all stakeholders, including governments and citizens, allowing them to reflect on trends and effectiveness of reduction measures. The new EC gave the green light to pass the CO2MVS from exploratory to implementing phase.

Background and Objectives: Profound knowledge on the load-dependent behavior of human soft tissues is required for the development of suitable replacements as well as for realistic computer simulations. Regarding the former, e.g., the anisotropy of a particular biological tissue has to be represented with site- and direction-dependent particular mechanical values. Contrary to this concept of consistent mechanical properties of a defined soft tissue, mechanical parameters of soft tissues scatter considerably when being determined in tensile tests. In spite of numerous measures taken to standardize the mechanical testing of soft tissues, several setup- and tissue-related factors remain to influence the mechanical parameters of human soft tissues to a yet unknown extent. It is to date unclear if measurement extremes should be considered a variation or whether these data have to be deemed incorrect measurement outliers. This given study aimed to determine mechanical parameters of the human cranial dura mater as a model for human soft tissues using a highly standardized protocol and based on this, critically evaluate the definition for the term mechanical ""variation"" of human soft tissue. Materials and Methods: A total of 124 human dura mater samples with an age range of 3 weeks to 94 years were uniformly retrieved, osmotically adapted and mechanically tested using customized 3D-printed equipment in a quasi-static tensile testing setup. Scanning electron microscopy of 14 samples was conducted to relate the mechanical parameters to morphological features of the dura mater. Results: The here obtained mechanical parameters were scattered (elastic modulus = 46.06 MPa, interquartile range = 33.78 MPa; ultimate tensile strength = 5.56 MPa, interquartile range = 4.09 MPa; strain at maximum force = 16.58%, interquartile range = 4.81%). Scanning electron microscopy revealed a multi-layered nature of the dura mater with varying fiber directions between its outer and inner surface. Conclusions: It is concluded that mechanical parameters of soft tissues such as human dura mater are highly variable even if a highly standardized testing setup is involved. The tissue structure and composition appeared to be the main contributor to the scatter of the mechanical parameters. In consequence, mechanical variation of soft tissues can be defined as the extremes of a biomechanical parameter due to an uncontrollable change in tissue structure and/or the respective testing setup.

Thiel embalming is a well-known method of anatomical fixation giving lifelike optical and haptic tissue properties. Beyond these characteristics, Thiel embalming may also be a promising method to provide lifelike tissues for validation purposes of human head biomechanics. Recent investigations using Thiel-embalmed human tissues of the upper and lower limb yielded contradicting biomechanical results on fixation-induced changes in the tissues' load-deformation behavior. It is to date unclear if Thiel embalming may have a softening or stiffening effect on human soft tissues or no global effect on biomechanics compared to the fresh state, with the latter being the most desirable outcome. The given study aimed at assessing the effects of Thiel embalming on the uniaxial tensile properties of human head soft tissues. Age-matched fresh and Thiel-embalmed dura mater, temporalis muscle, temporalis muscle fascia, and scalp samples were examined. Dura, fascia, and scalp samples showed significantly different elastic moduli compared to fresh tissues (all P < 0.01). The observed ultimate tensile strength supports the theory of an increased collagen crosslinking of the embalmed tissues when compared to the fresh state. Thiel-embalmed muscles failed any tensile testing approach as a result of the muscles dissolving due to the embalming. Furthermore, collagen integrity seems altered in scanning electron microscopy by the Thiel embalming, limiting their use for ultrastructural failure analyses. Thiel-embalmed soft tissues may consequently not serve to reflect the biomechanical properties of the human head. Consequently, the application of Thiel embalming should be limited to preliminary tests for biomechanical purposes.

With increasingly detailed imaging and mechanical analysis, modalities need arises to update methodology and assessment criteria for skull bone analysis to understand how bone microarchitecture and the presence of attached tissues may affect the response to mechanical load. The main aim was to analyze the effect of macroscopic and microstructural features, as well as periosteal attachment, on the mechanical properties of human skull bone. Fifty-six skull specimens from ethanol-phenoxyethanol-embalmed cadavers were prepared from two human cadavers. Assuming symmetry of the skull, all samples from one-half each were stripped of periosteum and dura mater, while the soft tissues were kept intact on the remaining samples on the contralateral side. The specimens were analyzed using microcomputed tomography to assess trabecular connectivity density, total surface area, and volume ratio. The specimens were loaded under three-point bend tests until fracture with optical co-registration. The bone fragments were then lyophilized to measure their water content. With increasingly detailed imaging and mechanical analysis modalities, there is a need to update methodology and assessment criteria for skull bone analysis to understand how the bone microarchitecture and the presence of attached tissues may affect the response to mechanical load. The mechanical properties were negatively correlated to bone thickness and water content. Conversely, most microarchitectural features did not influence either mechanical parameter. The correlation between mechanical response data and morphologic properties remains similar between the results of embalmed tissues presented here and fresh osseous tissue from literature data. The findings presented here add to the existing methodology to assess human skull for research purposes. The interaction between most microarchitectural features in ethanol-phenoxyethanol-embalmed embalmed skull samples and bending stress appear to be minute.

Background and aims: The human iliotibial tract (IT) is increasingly used in different types of musculoskeletal models. Previous findings indicate age-dependent changes of the human IT tensile properties, these lack confirmation to date. The relationship of the human IT and anthropometrical parameters, such as body height and weight has not been investigated before. Materials and methods: 33 fresh human IT samples (age range 4 months to 93 years) were uniaxially tested using digital imaging correlation and the latest advances in 3D-printing to standardize biomechanical soft tissues testing. Results: The tensile parameters of the human IT are not age-dependent, except for the maximum strain in males. Height significantly correlated to elastic modulus, tensile strength and maximum strain of the human IT in males. Females just showed a significant correlation between maximum strain and weight, which was contrary to the findings in males. Discussion and conclusion: Age-dependency of human IT tensile parameters could not be confirmed in the larger sample size investigated in this study. Due to the strong correlation with the tensile IT parameters in males, we suggest that height should be integrated when the IT is used in simulations, such as finite element analyses of the hip and knee.

Purpose Current forensic analysis of blunt force trauma relies on the use of cadaveric or animal tissues, posing ethical and reproducibility concerns. Artificial substitutes may help overcome such issues. However, existing substitutes exhibit poor anatomic and mechanical biofidelity, especially in the choice of skull simulant material. Progress has been made in identifying materials that have similar mechanical properties to the human skull bone, with the potential to behave similarly in mechanical loading. Aims To compare the biomechanical properties of the human calvarial bone with an epoxy resin-based simulant material. Data collected was also used to analyse the effect of periosteal attachment on the mechanical properties of skull bone compared with that of the counterpart samples. Methods Fifty-six human skull bone specimens were prepared from two cadaveric heads. Half of these specimens were removed of periosteum and dura mater as the PR (periosteum removed) group, whereas periosteum was left attached in the PA (periosteum attached) group. Duplicates of the bone specimens were fabricated out of an epoxy resin and paired in corresponding PR and PA groups. The specimens were loaded under three-point bending tests until fracture with image-based deformation detection. Results Comparison of the epoxy resin and skull specimens yielded similarity for both the PR and PA groups, being closer to the PA group (bending modulus resin PR 2665 MPa vs. skull PR 1979 MPa, resin PA 3165 MPa vs. skull PA 3330 MPa; maximum force resin PR 574 N vs. skull PR 728 N, resin PA 580 N vs. skull PA 1034 N; strain at maximum force resin PR 2.7% vs. skull PR 5.1%, resin PA 2.3% vs. skull PA 3.5%, deflection at maximum force resin PR 0.5 mm vs. skull PR 0.8 mm, resin PA 0.5 mm vs. skull PA 1.0 mm). Bending strength was significantly lower in the resin groups (resin PR 43 MPa vs. skull PR 55 MPa, resin PA 44 MPa vs. skull PA 75 MPa). Moreover, the correlations of the mechanical data exhibited closer accordance of the PR group with the epoxy resin compared with the PA group with the epoxy resin. Conclusions The load-deformation properties of the epoxy resin samples assessed in this study fell within a closer range to the skull specimens with PR than with PA. Moreover, the values obtained for the resin fall within the reference range for skull tissues in the literature suggesting that the proposed epoxy resin may provide a usable artificial substitute for PA but does not totally represent the human skull in its complex anatomical structure.

Cow milk has a positive effect on bone health due to the effects of its protein, fat, lipid, vitamin, and mineral components. Sheep milk contains a unique composition of all of these components. However, to the best of our knowledge the benefits of sheep milk in relation to bone development have not been studied. The aim of the present study was to determine the effects of the consumption of sheep milk in comparison to cow milk on the structural and physical characteristics of growing bone in a rat model. Newly weaned male rats were fed either cow milk, sheep milk or sheep milk diluted to the same total solids content as cow milk for 28 days in addition to a basal chow. At the end of the feeding period animals were euthanized, the femora harvested and stored. The femora were analysed by m-CT, mechanical bending tests, and ICP-MS. Rats consuming sheep milk in the trial were found to have significantly higher trabecular bone surface density and trabecular bone surface to volume ratio (p < 0.05) when compared to the rats consuming cow milk. No significant differences were observed in the mechanical properties and the mineral composition of the bones (p > 0.05). With the exception of Rb, which was found to be present in higher concentrations in rats consuming sheep milk (p < 0.05). Our results indicate that consumption of sheep milk may positively influence the structural integrity of bone, which may result in an enhancement of bone health.

Introduction: Colonoscopy is a commonly-performed procedure to diagnose pathology of the large intestine. Perforation of the colon is a rare but feared complication. It is currently unclear how much force is actually required to cause such injury nor how this is altered in certain diseases. Our aim was to analyze the forces required to perforate the colon in experiments using porcine tissues. Methods: Using 3D printing technology, models of two commercially available colonoscope heads were printed under three configurations: straight (I), 90°- bent (L) and fully bent (U). Samples of porcine colon were assessed with the models and configurations under perpendicular and angular load application and these data compared to the maximum force typically exerted by experienced colonoscopists. Results: The force required for perforation was significantly lower for the I compared to the L of the larger colonoscope head configuration under angular loading (14.1 vs. 46.5 N). Similar differences were found for linear stiffness when loaded (I vs. L small when loaded perpendicular: 0.8 vs. 2.4 N/mm, I vs. L large when loaded angled 0.7 vs. 2.1 N/mm). The mode and site of failure varied significantly between the scopes, with delamination of the mucosa/submucosa below the sample (96%) for the I, blunt mucosa/submucosa/muscularis failure adjacent to the loading site (77%) for the L, and failure of all colon layers lateral to the loading site (59%) for the U configuration, respectively. Perpendicular and angulated loading resulted in similar load-deformation values. Maximum forces typically exerted by colonoscopists averaged 13.9-27.9 N, depending on the colonoscope model and head configuration. Discussion: The force required for colon perforation varies depending on the type mode of loading and is likely lower than the force an experienced colonoscopist would exert in daily practice. There is a real risk of perforation, especially when the end of the scope is advancing directly into the colonic wall. The given experimental setup allowed to obtain reliable data of the colon in a standardized scenario, forming the basis for further experiments.

Ill-defined, multi-component mixtures of steroidal pharmaceuticals are present in the aquatic environment. Fish are extremely sensitive to some of these steroids. It is important to know how fish respond to these mixtures, and from that knowledge develop methodology that enables accurate prediction of those responses. To provide some of the data required to reach this objective, pairs of fish were first exposed to five different synthetic steroidal pharmaceuticals (one estrogen, EE2; one androgen, trenbolone; one glucocorticoid, beclomethasone dipropionate; and two progestogens, desogestrel and levonorgestrel) and concentration-response data on egg production obtained. Based on those concentration-response relationships, a five component mixture was designed and tested twice. Very similar effects were observed in the two experiments. The mixture inhibited egg production in an additive manner predicted better by the model of Independent Action than that of Concentration Addition. Our data provide a reference case for independent action in an in vivo model. A significant combined effect was observed when each steroidal pharmaceutical in the mixture was present at a concentration which on its own would produce no statistically significant effect (something from ‘nothing’). Further, when each component was present in the mixture at a concentration expected to inhibit egg production by between 18% (Beclomethasone diproprionate) and 40% (trenbolone), this mixture almost completely inhibited egg production: a phenomenon we term ‘a lot from a little’. The results from this proof-of-principle study suggest that multiple steroids present in the aquatic environment can be analysed for their potential combined environmental risk.

Effect-based tools (EBT) based on estrogen receptor (ER) activation are widely used to monitor xeno-estrogens in environmental samples. We previously reported that established human (MELN cells, expressing hERα) and zebrafish (ZELHα cells expressing zfERα, ZELHβ2 cells expressing zfERβ2) reporter cell lines are robust, reliable and sensitive to detect well-known ER ligands. However, they can respond to surface water and effluents samples differently, with samples being selectively active either on human or zebrafish cells. Different responses may be due to non-identified active substances and/or interactions with other chemicals, as ER activation depends on the intrinsic potency of the chemical and on the cell context (e.g. metabolism). Therefore, the present study aimed to compare the responses of zebrafish and human EBT to selected environmental pollutants, alone and in combination. Interactions between chemicals were taken into account by (1) assessing both activation and inhibition of ER response, (2) using concentration addition (CA) model to predict additive effects, and (3) combining active and non-active pollutants. While genistein and bisphenol A (BPA) were active on all EBTs, marked differences were observed for other chemicals. Triphenylphosphate (TPP) and benzo(a)pyrene (BaP) induced ER activation in MELN cells but decreased E2 response in zebrafish cells. Chlorophene, benzo(b)fluoranthene and propiconazole selectively inhibited the E2-induced reporter gene response in zebrafish cells. The first 12-component mixture results indicated that the effects in ZELHα and ZELHβ2 cells were driven by inhibiting chemicals (TPP and propiconazole), while the estrogenic activity of BPA and genistein was not detected, although predicted. In MELN cells, the estrogenic response (driven by genistein, BPA and TPP) agreed overall well with CA prediction. Work is ongoing with other mixture designs. Altogether, the results indicate that both the cell context (fish vs human) and the effects of anti-estrogenic chemicals influence ER response. In line with previous observations on environmental samples, our study raises the question of cross-species differences and fish-specific effects, highlighting the importance of the cell model for water quality biomonitoring. Future work will focus on the refinement of estrogenicity assessment by taking into account anti-estrogenic effects in environmental samples. This work was performed within the EU FP7 project SOLUTIONS.

The Monitoring and Verification Support (MVS) capacity is a technical capacity to provide support to the policy makers and the scientific community. The MVS aims at supplying extra evidence on the emissions levels and trends, coupling anthropogenic activities and associated emissions with the atmospheric patterns in greenhouse gas concentrations. The MVS thus intends to support enhancing the quality of national greenhouse gas emission inventories and complement the data available under the UNFCCC measurement, reporting and verification framework. The MVS will include top-down verification of emissions using independent atmospheric observations and, in particular, observations acquired by spaceborne sensors at high temporal and spatial resolutions all over the globe.

The goal of the GHG-CCI project (http://www.esa-ghg-cci.org/) of ESA's Climate Change Initiative (CCI) is to generate global atmospheric satellite-derived carbon dioxide (CO2) and methane (CH4) data sets as needed to improve our understanding of the regional sources and sinks of these important greenhouse gases (GHG). Here we present an overview about the latest data set called Climate Research Data Package No. 3 (CRDP3). We focus on the GHG-CCI project core data products, which are near-surface-sensitive column-averaged dry air mole fractions of CO2 and CH4, denoted XCO2 (in ppm) and XCH4 (in ppb) retrieved from SCIAMACHY/ENVISAT (2002-2012) and TANSO-FTS/GOSAT (2009-today) nadir mode radiance observations in the near-infrared/shortwave-infrared spectral region. The GHG-CCI products are primarily individual sensor Level 2 products. However, we also generate merged Level 2 products ("EMMA products"). Here we also present a first GHG-CCI Level 3 product, namely XCO2 and XCH4 in Obs4MIPs format (monthly, 5°×5°).

Operationalizing a Global Carbon Observing and Analysis System (www.geocarbon.net) would provide a sound basis for monitoring actual carbon fluxes and thus getting quantities right when pricing carbon – be it in a cap-and-trade scheme or under a tax regime. However, such monitoring systems are expensive and—especially in times of economic weakness—budgets for science and environmental policy are under particular scrutiny. In this study, we attempt to demonstrate the magnitude of benefits of improved information about actual carbon fluxes. Such information enables better-informed policy-making and thus paves the way for a more secure investment environment when decarbonizing the energy sector. The numerical results provide a robust indication of a positive social value of improving carbon monitoring systems when compared to their cost, especially for the more ambitious climate policies.