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Abstract Pulmonary arterial hypertension is a rare but life-threatening and clinically heterogeneous disease. The diagnostic schedule of this disorder is complex, and no specific indicator of the arterial etiology has been explored. In this study, untargeted plasma metabolomics was applied to evaluate the metabolic fingerprints of pulmonary arterial hypertension patients. Plasma samples were prepared using a new approach, which applies proteinase K during the sample preparation procedure to increase the metabolite coverage. The metabolic fingerprints were determined via LC–MS and subsequently analyzed with the use of both uni- and multivariate statistics. A total of 21 metabolites were discovered to be significantly altered in pulmonary arterial hypertensive patients. The metabolites were mainly related to the phospholipid metabolic pathways. In this study, decreases were found in the phosphatidylcholines (PCs) [PC(32:0), PC(40:7), PC(42:7)], phosphatidylethanolamine PE(18:0/18:2), lysophosphatidylethanolamines (LPEs) [LPE(22:6), LPE(18:2), LPE(18:0), LPE(20:4), LPE(20:1), LPE(20:0)], lysophosphatidylcholine LPC(20:4) and lysophosphatidylserine LPS(19:0), as well as increase of sphingomyelin SM(36:2), in the plasma samples of pulmonary arterial hypertensive patients in comparison to the control group. Besides their function as components of the biological membranes, these metabolites are also involved in the intracellular signaling pathways that are related to cell proliferation and apoptosis. The results obtained during this study confirm the potential of (untargeted) metabolomics to identify the molecular characteristics of the pathophysiology of pulmonary arterial hypertension. The clinical relevance of this study constitutes the selection of a metabolic panel that can potentially detect and properly diagnose the disease.

Combined intracapsular and extracapsular fractures of the proximal femur—segmental fractures of neck of femur (SFNOF)—are rare and complex injuries. Literature regarding SFNOF is very limited; only one small retrospective study and 19 unique case reports have been described. We report the case of a 42-year-old man who suffered a compound subcapital femur fracture type Garden IV and an ipsilateral multifragmentary greater trochanter fracture from severe crush trauma. Neither the precise fracture constellation nor our management strategy, primary cemented total hip arthroplasty combined with tension band cerclage and triple K-wire trochanteric fixation, has been described in contemporary literature. We conclude that SFNOF needs clear categorization and derivative treatment principles. Prosthesis longevity, risk of nonunion, and avascular necrosis should be considered.

Renal dysplasia is a severe congenital abnormality of the kidney parenchyma, which is an important cause of end-stage renal failure in childhood and early adulthood. The diagnosis of renal dysplasia relies on prenatal or postnatal ultrasounds as children show no specific clinical symptoms before chronic kidney disease develops. Prompt diagnosis is important in terms of early introduction of nephroprotection therapy and improved long-term prognosis. Metabolomics was applied to study children with renal dysplasia to provide insight into the changes in biochemical pathways underlying its pathology and in search of early indicators for facilitated diagnosis. The studied cohort consisted of 72 children, 39 with dysplastic kidneys and 33 healthy controls. All subjects underwent comprehensive urine metabolic profiling with the use of gas chromatography and liquid chromatography coupled to mass spectrometry, with two complementary separation modes of the latter. Univariate and multivariate statistical calculations identified a total of nineteen metabolites, differentiating the compared cohorts, independent of their estimated glomerular filtration rate. Seven acylcarnitines, xanthine, and glutamine were downregulated in the urine of renal dysplasia patients. Conversely, renal dysplasia was associated with higher urinary levels of dimethylguanosine, threonic acid or glyceric acid. This is the first metabolomic study of subjects with renal dysplasia. The authors define a characteristic urine metabolic signature in children with dysplastic kidneys, irrespective of renal function, linking the condition with altered fatty acid oxidation, amino acid and purine metabolisms.

Abstract Background Assessment of chest pain in general practice is challenging. General practitioners (GPs) often feel uncertainty when dealing with chest pain. The role of new diagnostic tools is yet unclear. Therefore, we aimed to learn: (1) whether or not GPs experience a change in incidence and presentation of chest pain, (2) how GPs deal with uncertainty, and (3) which thoughts, demands and doubts concerning new diagnostic tools occur. Methods Semi-structured, face to face interview based study, aiming at six main subjects: experienced changes in prevalence of chest pain, the management of chest pain patients, dealing with uncertainty, the GPs’ approach in referring chest pain patients, GPs’ attitude towards ‘unnecessary’ referrals, and the GPs’ suggestions for improving the management of chest pain patients. Results 145 GPs in Belgium and the Netherlands were invited to participate, 27 (15 Flemish and 12 Dutch) GPs were interviewed. Data saturation was reached. The number of patients having an acute coronary syndrome among chest pain patients is decreasing, whereas the presentation of atypical complaints increases, together leading to more uncertainty. GPs rely on their own judgment above all, and desire new diagnostic tools only when these tools are of proven added value. Conclusion The incidence of chest pain in general practice is not decreasing according to the GPs. However, the presentation of chest pain is changing. GPs feel relatively comfortable with referring a considerable number of chest pain patients without ACS, as over-referral is safe. Uncertainty is regarded as a substantial element of their profession. New diagnostic tools are awaited with cautiousness.

Atmospheric correction plays a crucial role among the processing steps applied to remotely sensed hyperspectral data. Atmospheric correction comprises a group of procedures needed to remove atmospheric effects from observed spectra, i.e. the transformation from at-sensor radiances to at-surface radiances or reflectances. In this paper we present the different steps in the atmospheric correction process for APEX hyperspectral data as applied by the Central Data Processing Center (CDPC) at the Flemish Institute for Technological Research (VITO, Mol, Belgium). The MODerate resolution atmospheric TRANsmission program (MODTRAN) is used to determine the source of radiation and for applying the actual atmospheric correction. As part of the overall correction process, supporting algorithms are provided in order to derive MODTRAN configuration parameters and to account for specific effects, e.g. correction for adjacency effects, haze and shadow correction, and topographic BRDF correction. The methods and theory underlying these corrections and an example of an application are presented.

Hyperspectral imagery originating from airborne sensors is nowadays widely used for the detailed characterization of land surface. The correct mapping of the pixel positions to ground locations largely contributes to the success of the applications. Accurate geometric correction, also referred to as “orthorectification”, is thus an important prerequisite which must be performed prior to using airborne imagery for evaluations like change detection, or mapping or overlaying the imagery with existing data sets or maps. A so-called “ortho-image” provides an accurate representation of the earth’s surface, having been adjusted for lens distortions, camera tilt and topographic relief. In this paper, we describe the different steps in the geometric correction process of APEX hyperspectral data, as applied in the Central Data Processing Center (CDPC) at the Flemish Institute for Technological Research (VITO, Mol, Belgium). APEX ortho-images are generated through direct georeferencing of the raw images, thereby making use of sensor interior and exterior orientation data, boresight calibration data and elevation data. They can be referenced to any userspecified output projection system and can be resampled to any output pixel size.

Small unmanned aerial vehicles are increasingly being employed for environmental monitoring at local scale, which drives the demand for compact and lightweight spectral imagers. This paper describes the geospectral camera, which is a novel compact imager concept. The camera is built around an innovative detector which has two sensor elements on a single chip and therefore offers the functionality of two cameras within the volume of a single one. The two sensor elements allow the camera to derive both spectral information as well as geometric information (high spatial resolution imagery and a digital surface model) of the scene of interest. A first geospectral camera prototype has been developed. It uses a linear variable optical filter which is installed in front of one of the two sensors of the MEDUSA CMOS imager chip. A accompanying software approach has been developed which exploits the simultaneous information of the two sensors in order to extract an accurate spectral image product. This method has been functionally demonstrated by applying it on image data acquired during an airborne acquisition.

We review and discuss the latest developments and technology options for 45 nm node and below, with scaled planar bulk MOSFETs and MuGFETs as emerging devices. One of the main metal gate (MG) candidates for scaled CMOS technologies are fully silicided (FUSI) gates. In this work, by means of a selective and controlled poly etch-back integration process, dual work-function Ni-based FUSI/HfSiON CMOS circuits with record ring oscillator performance (high-VT) are reported (17 ps at VDD=1.1 V and 20 pA/μm Ioff), meeting the ITRS 45 nm node requirement for low-power (LP) CMOS. Compatibility of FUSI and other MG with known stress boosters like stressed CESL (contact-etch-stop-layer with high intrinsic stress) or embedded SiGe in the pMOS S/D regions is validated. To obtain MuGFET devices that are competitive, as compared to conventional planar bulk devices, and that meet the stringent drive and leakage current requirements for the 32 nm node and beyond, higher channel mobilities are required. Results obtained by several strain engineering methods are presented here.

Slatted floors and liquid manure–handling systems in intensive housing systems preclude the use of large straw quantities as enrichment material for pigs. Consequently, there is a need for alternative enrichment strategies, for example, by using suitable applications providing pigs with small straw quantities, which are associated with low straw waste. The aim of this study was to evaluate the effects of a straw dispenser filled with fully chopped straw on the behavior and lesions in weanling pigs. A total of 365 weanling pigs, housed in single-sex groups (gilts and intact boars), were randomly divided in 2 groups. Half of the pigs had access to a straw dispenser (straw; n = 187), and the other half had no access to straw (control; n = 178). They were housed in the weanling unit for a period of 7 weeks (7-20 kg) and received liquid feed. One straw dispenser was provided per pen, accessible to 3 pigs at a time of 10 to 15 pigs in the pen, and positioned above the feed trough. To receive straw, pigs had to manipulate the dispensing unit on the bottom of the dispenser. Behavioral observations were carried out twice a week, and present lesions were also scored on these days by the same observer. Data were analyzed using a logistic mixed model and a Fisher exact test. No differences were found for biting behavior toward different body parts between control and straw pigs. There was also no effect of gender. In boars, aggressive behavior occurred more in straw groups compared to control groups, which might be related to competition. This finding is also reflected in more lesions on the middle part of the body in straw groups. A lack of difference in lesion scores for tail and ears between the 2 groups suggests that the dispenser provided insufficient distraction for weanling pigs compared to a barren environment. However, the position of the straw dispenser must be kept in mind, as this caused pigs to perform straw-directed behavior mainly in the feed trough. In this study, based on behavioral observations and lesion scores, it seems that the straw dispenser did not provide pigs with more advantages compared to pigs in a barren environment. Moreover, competition was observed in pens with boars, which might be related to the fact that only one dispenser was provided per pen. It should, however, be taken into account that the position of the dispenser might not have been the most suitable as it possibly caused mixing of feed and straw. [ABSTRACT FROM AUTHOR]