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Access to adequate pollen sources in agricultural landscapes is critical for the nutrition and development of bees. The type and quantity of pollen available to bees and may be determined by local plant diversity, land-use intensity and landscape structure but different bee species likely respond differently to these parameters. Identifying community and specific responses is therefore imperative to understand pollinator population dynamics in agricultural landscapes. We sampled bees in 36 plots along a land-use gradient at 4 sites in Belgium and Germany over two years. We collected 1821 bees from 100 bee species and constructed a pollen foraging network with 36 common wild bee species based on pollen metabarcoding. We investigated differences in community responses and species-specific responses to environmental variables. Landscape heterogeneity positively correlated with bee species richness, diversity and functional richness, and significantly explained bee community composition per plot. Bee collected pollen diversity correlated with bee species diversity. Furthermore, landscape heterogeneity positively correlated with bee collected pollen diversity when pooling abundant bee species, while it did not correlate with pollen diversity of the most abundant generalists. Land-use intensity and local plant diversity had no significant effect on bee diversity. Larger bees showed negative responses to increasing land-use intensity and bees with more specialized diets showed positive correlations with landscape heterogeneity. Our study goes beyond mere floral diversity and provides new insight into the responses of wild bee communities to landscape structure and regional pollen availability, as well as the interplay between bee abundance and pollen foraging traits. Our results highlight the importance of determining species-specific nutritional needs and considering landscape level structure in pollinator conservation programs.
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Methods of ablation imprints in solid targets are widely used to characterize focused X-ray laser beams due to a remarkable dynamic range and resolving power. A detailed description of intense beam profiles is especially important in high-energy-density physics aiming at nonlinear phenomena. Complex interaction experiments require an enormous number of imprints to be created under all desired conditions making the analysis demanding and requiring a huge amount of human work. Here, for the first time, we present ablation imprinting methods assisted by deep learning approaches. Employing a multi-layer convolutional neural network (U-Net) trained on thousands of manually annotated ablation imprints in poly(methyl methacrylate), we characterize a focused beam of beamline FL24/FLASH2 at the Free-electron laser in Hamburg. The performance of the neural network is subject to a thorough benchmark test and comparison with experienced human analysts. Methods presented in this Paper pave the way towards a virtual analyst automatically processing experimental data from start to end.
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The conversion of photon energy into other energetic forms in molecules is accompanied by charge moving on ultrafast timescales. We directly observe the charge motion at a specific site in an electronically excited molecule using time-resolved x-ray photoelectron spectroscopy (TR-XPS). We extend the concept of static chemical shift from conventional XPS by the excited-state chemical shift (ESCS), which is connected to the charge in the framework of a potential model. This allows us to invert TR-XPS spectra to the dynamic charge at a specific atom. We demonstrate the power of TR-XPS by using sulphur 2p-core-electron-emission probing to study the UV-excited dynamics of 2-thiouracil. The method allows us to discover that a major part of the population relaxes to the molecular ground state within 220-250 fs. In addition, a 250-fs oscillation, visible in the kinetic energy of the TR-XPS, reveals a coherent exchange of population among electronic states.
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Wild bee populations are declining due to human activities, such as land use change, which strongly affect the composition and diversity of available plants and food sources. The chemical composition of food (i.e., nutrition) in turn determines the health, resilience, and fitness of bees. For pollinators, however, the term 'health' is recent and is subject to debate, as is the interaction between nutrition and wild bee health. We define bee health as a multidimensional concept in a novel integrative framework linking bee biological traits (physiology, stoichiometry, and disease) and environmental factors (floral diversity and nutritional landscapes). Linking information on tolerated nutritional niches and health in different bee species will allow us to better predict their distribution and responses to environmental change, and thus support wild pollinator conservation.
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Biodiversidad , Polinización , Animales , Abejas , Ecosistema , Flores/fisiología , Fenotipo , Plantas , Polinización/fisiologíaRESUMEN
Purpose. Pulmonary-renal syndrome (PRS) is characterized by diffuse alveolar hemorrhage and rapidly progressive glomerulonephritis mainly due to autoimmune etiologies. Seronegative PRS is a challenging entity to the clinician, since early diagnosis may be missed leading to delayed appropriate treatment. Materials and Methods. We present the clinical course of a 77-year-old patient who was admitted under the suspected diagnosis of pneumogenic sepsis and septic renal failure with fever, dyspnea, and elevated CRP levels. The diagnosis of pulmonary-renal syndrome was initially missed because of the absence of autoantibodies in all serological findings. Results. Despite delayed initiation of immunosuppressive therapy and a prolonged period of dialysis and extracorporeal membrane oxygenation the patient recovered well and was released to a rehabilitation center with nearly normalized creatinine levels. The diagnosis of PRS was established by renal biopsy. Conclusion. This case illustrates the important differential diagnosis of seronegative pulmonary-renal syndrome in patients with pulmonary and renal impairment.
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Biosimilars are regulated differently from small-molecule generic, chemically derived medicines. The complexity of biological products means that small changes in manufacturing or formulation may result in changes in efficacy and safety of the final product. In the face of this complexity, the regulatory landscape for biosimilars continues to evolve, and global harmonization regarding requirements is currently lacking. It is essential that clinicians and patients are reassured that biosimilars are equally safe and effective as their reference product, and this is particularly important when interchangeability, defined as 'changing one medicine for another one which is expected to achieve the same clinical effect in a given clinical setting in any one patient', is considered. Although the automatic substitution (i.e. substitution without input from the prescribing healthcare provider) of biosimilars for reference products is currently not permitted by the majority of countries, this may change in the future. In order to demonstrate interchangeability between reference products and a biosimilar, more stringent and specific studies of the safety and efficacy of biosimilars are likely to be needed; however, guidance on the design of and the need for any such studies is currently limited. The present article provides an overview of the current regulatory framework around the demonstration of interchangeability with biosimilars, with a specific focus on biosimilar insulin analogues, and details experiences with other biosimilar products. In addition, designs for studies to evaluate interchangeability with a biosimilar insulin analogue product are proposed and a discussion about the implications of interchangeability in clinical practice is included.
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Biosimilares Farmacéuticos , Sustitución de Medicamentos , Control de Medicamentos y Narcóticos , Hipoglucemiantes , Insulina/análogos & derivados , Química Farmacéutica , Medicamentos Genéricos , HumanosRESUMEN
To predict changes in the shape of the breast in different imaging devices, a Coupled Eulerian-Lagrangian (CEL) mechanical model is developed. The CEL method allows for a more adequate representation of the very large deformations experienced by the soft and incompressible tissues of the breast. The mechanical response of the tissues is based on advanced mathematical formulations and experimental data from the literature. Realistic geometries generated from Magnetic Resonance (MR) images are used as study cases. Furthermore, specific boundary conditions are applied to the model to predict the shape of the breast and the location of the internal tissues in a prototype microwave breast imaging system, where an immersion medium is used. The accuracy of the model was assessed by comparing the numerical results with a laser scan of the same subject in the microwave breast imaging system.
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Mama/citología , Imagen por Resonancia Magnética , Fenómenos Mecánicos , Modelos Biológicos , Fenómenos Biomecánicos , Humanos , MicroondasRESUMEN
An extension of the application of calcium phosphate cements (CPC) to load-bearing defects, e.g. in vertebroplasty, would require less brittle cements with an increased fracture toughness. Here we report the modification of CPC made of alpha-tricalcium phosphate (α-TCP) with 2-hydroxyethylmethacrylate (HEMA), which is polymerised during setting to obtain a mechanically stable polymer-ceramic composite with interpenetrating organic and inorganic networks. The cement liquid was modified by the addition of 30-70 % HEMA and ammoniumpersulfate/tetramethylethylendiamine as initiator. Modification of α-TCP cement paste with HEMA decreased the setting time from 14 min to 3-8 min depending on the initiator concentration. The 4-point bending strength was increased from 9 MPa to more than 14 MPa when using 50 % HEMA, while the bending modulus decreased from 18 GPa to approx. 4 GPa. The addition of ≥50 % HEMA reduced the brittle fracture behaviour of the cements and resulted in an increase of the work of fracture by more than an order of magnitude. X-ray diffraction analyses revealed that the degree of transformation of α-TCP to calcium deficient hydroxyapatite was lower for polymer modified cements (82 % for polymer free cement and 55 % for 70 % HEMA) after 24 h setting, while the polymerisation of HEMA in the cement liquid was quantitative according to FT-IR spectroscopy. This work demonstrated the feasibility of producing fracture resistant dual-setting calcium phosphate cements by adding water soluble polymerisable monomers to the liquid cement phase, which may be suitable for an application in load-bearing bone defects.
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Cementos para Huesos/química , Fosfatos de Calcio/química , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos XRESUMEN
Soybean dwarf virus (SbDV) exists as several distinct strains based on symptomatology, vector specificity, and host range. Originally characterized Japanese isolates of SbDV were specifically transmitted by Aulacorthum solani. More recently, additional Japanese isolates and endemic U.S. isolates have been shown to be transmitted by several different aphid species. The soybean aphid, Aphis glycines, the only aphid that colonizes soybean, has been shown to be a very inefficient vector of some SbDV isolates from Japan and the United States. Transmission experiments have shown that the soybean aphid can transmit certain isolates of SbDV from soybean to soybean and clover species and from clover to clover and soybean with long acquisition and inoculation access periods. Although transmission of SbDV by the soybean aphid is very inefficient, the large soybean aphid populations that develop on soybean may have epidemiological potential to produce serious SbDV-induced yield losses.
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Huanglongbing (HLB), considered to be the most serious insect-vectored bacterial disease of citrus, is transmitted in nature by the Asian citrus psyllid Diaphorina citri and the African citrus psyllid Trioza erytreae. D. citri was discovered in southern Florida in 1998 and the HLB disease in 2005. Both have become established throughout citrus-producing areas of Florida. Murraya species are widely grown in southern Florida as ornamental hedges and are readily colonized by D. citri vectors. Colonies of D. citri, isolates of 'Candidatus Liberibacter asiaticus' from Taiwan and Florida, and the Murraya species were established in the BSL-3 biosecurity facility at Fort Detrick. In controlled inoculation experiments, D. citri transmitted 'Ca. L. asiaticus' into M. paniculata (34/36 plants) and M. exotica (22/23 plants), but not into Bergera (Murraya) koenigii. Disease symptoms rarely developed in Murraya plants; however, positive infections were determined by conventional and real-time polymerase chain reaction (PCR). Back-inoculations of 'Ca. L. asiaticus' from M. paniculata to Madam Vinous sweet orange resulted in disease development in 25% of the inoculated plants. Considerable variability was observed in infection rates, titer, and persistence of 'Ca. L. asiaticus' in infected Murraya.
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OBJECTIVE: To compare the efficacy and safety of a polyurethane dressing with a silicone sheet in the treatment of hypertrophic scars. METHOD: Sixty patients participated in this intra-individual 12-week clinical trial. Each scar was divided into two areas, to which the polyurethane dressing and the silicone sheet were randomly allocated. The primary outcome measure was the percentage change in the overall scar index (SI) between baseline and week 12. Secondary outcome measures included changes in skin redness, objectively measured by chromametry, and patients views on the aesthetic outcome of treatment. RESULTS: Both therapies achieved favourable results for all of the above outcome measures. Results were comparable for the primary outcome measure: 29.4% versus 33.7% for the silicone sheet and polyurethane product respectively. The decrease in the overall SI was significantly more pronounced for the polyurethane product after week 4 (5.6% versus 15.8% for the silicone sheet; p<0.0001) and week 8 (20.2% versus 27.1%; p=0.012). CONCLUSION: Both regimens were associated with a significant reduction in the clinical signs of hypertrophic scars over 12 weeks of treatment. The polyurethane dressing demonstrated a significantly more pronounced reduction in severity of these clinical signs after four and eight weeks of treatment and was better tolerated than the silicone sheet. l DECLARATION OF INTEREST: This study was funded by Beiersdorf AG. proDERM is an independent research company, and none of the authors have an interest in the sponsors commercial activities.
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Vendajes/normas , Cicatriz Hipertrófica/terapia , Poliuretanos/normas , Siliconas/normas , Adolescente , Adulto , Cicatriz Hipertrófica/patología , Estética , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Fotometría , Índice de Severidad de la Enfermedad , Método Simple Ciego , Cuidados de la Piel/métodos , Estadísticas no Paramétricas , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
This study used multi-frequency bioimpedance spectroscopy (BIS) of the arm and whole body to estimate muscle mass (MM) and subcutaneous adipose tissue (SAT) in 31 hemodialysis (HD) patients comparing these results with magnetic resonance imaging (MRI) and body potassium ((40)K) as gold standards. Total body and arm MM (MM(MRI)) and SAT (SAT(MRI)) were measured by MRI. All measurements were made before dialysis treatment. Regression models with the arm (aBIS) and whole body (wBIS) resistances were established. Correlations between gold standards and the BIS model were high for the arm SAT (r(2) = 0.93, standard error of estimate (SEE) = 3.6 kg), and whole body SAT (r(2) = 0.92, SEE = 3.5 kg), and for arm MM (r(2) = 0.84, SEE = 2.28 kg) and whole body MM (r(2) = 0.86, SEE = 2.28 kg). Total body MM and SAT can be accurately predicted by arm BIS models with advantages of convenience and portability, and it should be useful to assess nutritional status in HD patients.
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Tejido Adiposo , Composición Corporal , Impedancia Eléctrica , Músculos , Diálisis Renal , Negro o Afroamericano , Brazo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estado Nutricional , Potasio/análisis , Estándares de Referencia , Reproducibilidad de los ResultadosRESUMEN
OBJECTIVE: To establish a new wound model that can induce uniform abrasions and use it to assess the healing properties of a range of products commonly applied to these wounds. METHOD: Ten healthy volunteers were enrolled into an open-label, randomised, intra-individual comparison pilot study. Five standardised, superficial abrasions were induced on their forearms by repeatedly scrubbing the skin with a surgical brush until the first signs of uniform glistening and punctuate bleeding were observed. Three products that promote a moist wound environment (polyurethane, hydrocolloid, hydrogel) and two standard plasters were randomly allocated to the test areas. RESULTS: Evaluation of wound healing on days 2, 5, 8 and 14 +/- 1 showed best results for the polyurethane and hydrocolloid plasters. Visible re-epithelialisation was recorded on days 5 and 8. More than 50% of the wound area had closed. Video microscope images support these findings. The investigator and volunteers assessed cosmetic outcomes on day 31 +/- 2. Best results were obtained for the polyurethane and hydrocolloid products, which had high mean scores close to the maximum of 10. Histological examination of biopsies taken from the abrasions of two volunteers showed the dermis remained intact, making the model highly suitable for the study of superficial wounds. CONCLUSION: Uniform and identical standardised wounds created using an abrasive brush technique can be used to reliably detect differences in the performance of plasters intended for superficial wounds. In general, products that promote a moist wound environment produced better results than those that promote a dry wound environment, with an earlier onset of healing and better healing outcomes. Superficial cutaneous wounds treated with polyurethane or hydrocolloid products demonstrated superior rates of re-epithelialisation and overall cosmetic outcomes. DECLARATION OF INTEREST: This study was funded by Beiersdorf AG. Neither author has any interest in the sponsor's commercial activities.
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Vendas Hidrocoloidales , Modelos Biológicos , Apósitos Oclusivos , Cicatrización de Heridas , Heridas y Lesiones/terapia , Adulto , Femenino , Humanos , Masculino , Proyectos Piloto , Poliuretanos , Estándares de Referencia , Proyectos de Investigación , Heridas y Lesiones/patologíaRESUMEN
A one-dimensional silver (Ag) nanoparticle gradient layer is prepared from an aqueous colloidal solution upon a polystyrene (PS) coated silicon (Si) substrate. For preparation two walls of different wettability are used. The 40 nm PS-layer exhibits a locally constant film thickness due to the strong roughness correlation with the underlying Si-substrate and is less wettable as compared to the glass plate placed above. The Ag nanoparticles have a triangular prism-like shape. The structural characterization of the obtained complex gradient formed by drying is performed with microbeam grazing incidence small-angle x-ray scattering based on compound refractive lenses. Due to the adsorption from aqueous solution in the selective geometry a double gradient type structure defined by two areas with characteristic lateral lengths and a cross-over regime between both is observed.
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There is a severe shortage of knowledge of bee biogeography. Some former studies have highlighted a link between bee diversity and xeric ecosystems, but we know practically nothing of the macro-ecological factors driving bee diversity. The present study aims to analyse the main macro-ecological factors driving bee species-richness in the Saharan region. Our dataset includes 25,000+ records for localities in Africa, between 37 degrees and 10 degrees N. Maps and GIS were used to get a first overview of the distribution of the studied taxa. Partial least squares analysis (PLS) was used to study the impact of a set of ecological factors on the bee species richness (SR). The mapping highlighted the clustering of the highest bee SR values in some parts of the Saharan area (e.g. Maghreb, western Africa). In Central Sahara, there is an obvious topological coincidence of the high SR, the local mountain chains and the inland waters. The PLS helped to quantify the relationships between bee SR and a set of eco-climatic variables. It also highlighted a residual variance not explained by the considered descriptors. Our results recover the tight link between bee SR and xeric ecosystems. They also suggest that, within these ecosystems, bee SR is driven by an optimum of the energy-water balance (on which adjustment is allowed by the above gradients).
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Abejas/fisiología , Biodiversidad , Demografía , África del Norte , Animales , Agua Dulce , Sistemas de Información Geográfica , Geografía , Análisis MultivarianteRESUMEN
A general theoretical approach based on the decomposition of statistical fields into a sum of independently propagating transverse modes was used for the analysis of the coherence properties of the new free-electron laser source FLASH operated at 13.7 nm wavelength. The analysis shows that several transverse modes are contributing to the total radiation field of FLASH. The results of theoretical calculations are compared with measurements using Young's double-slit experiment. The coherence lengths in the horizontal and in the vertical directions 20 m downstream from the source are estimated at 300 and 250 microm, respectively.
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The interaction of intense extreme ultraviolet femtosecond laser pulses (lambda = 32.8 nm) from the FLASH free electron laser (FEL) with clusters has been investigated by means of photoelectron spectroscopy and modeled by Monte Carlo simulations. For laser intensities up to 5x10(13) W/cm(2), we find that the cluster ionization process is a sequence of direct electron emission events in a developing Coulomb field. A nanoplasma is formed only at the highest investigated power densities where ionization is frustrated due to the deep cluster potential. In contrast with earlier studies in the IR and vacuum ultraviolet spectral regime, we find no evidence for electron emission from plasma heating processes.
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Although many methods have been utilized to measure degrees of body hydration, and in particular to estimate normal hydration states (dry weight, DW) in hemodialysis (HD) patients, no accurate methods are currently available for clinical use. Biochemcial measurements are not sufficiently precise and vena cava diameter estimation is impractical. Several bioimpedance methods have been suggested to provide information to estimate clinical hydration and nutritional status, such as phase angle measurement and ratio of body fluid compartment volumes to body weight. In this study, we present a calf bioimpedance spectroscopy (cBIS) technique to monitor calf resistance and resistivity continuously during HD. Attainment of DW is defined by two criteria: (1) the primary criterion is flattening of the change in the resistance curve during dialysis so that at DW little further change is observed and (2) normalized resistivity is in the range of observation of healthy subjects. Twenty maintenance HD patients (12 M/8 F) were studied on 220 occasions. After three baseline (BL) measurements, with patients at their DW prescribed on clinical grounds (DW(Clin)), the target post-dialysis weight was gradually decreased in the course of several treatments until the two dry weight criteria outlined above were met (DW(cBIS)). Post-dialysis weight was reduced from 78.3 +/- 28 to 77.1 +/- 27 kg (p < 0.01), normalized resistivity increased from 17.9 +/- 3 to 19.1 +/- 2.3 x 10(-2) Omega m(3) kg(-1) (p < 0.01). The average coefficient of variation (CV) in three repeat measurements of DW(cBIS) was 0.3 +/- 0.2%. The results indicate that cBIS utilizing a dynamic technique continuously during dialysis is an accurate and precise approach to specific end points for the estimation of body hydration status. Since no current techniques have been developed to detect DW as precisely, it is suggested as a standard to be evaluated clinically.
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Líquidos Corporales/fisiología , Electrofisiología/métodos , Pierna/fisiología , Diálisis Renal , Algoritmos , Impedancia Eléctrica , Electrodos , Femenino , Humanos , Masculino , Análisis EspectralRESUMEN
Despite advances in dialysis technology and an increasing variety of effective phosphate binders (PB) target phosphate levels are achieved in only a minority of ESRD patients. This is only partly explained by insufficient weekly phosphate elimination (2400 - 3000 mg) with traditional 3x 4-5 h dialysis, which is significantly lower than the total amount of phosphorus (iP) accrued from dietary consumption during the same period (about 5000 g). In addition, meal-to-meal and day-to-day variability of dietary iP intake in conjunction with inadequate phosphate binder dosing in relation to meal iP content also may contribute to hyperphosphatemia. It was hypothesized that self-adjusting of PB dose to meal iP content by the patient himself will improve management of hyperphosphatemia. A specific Phosphate-Education-Program (PEP) was developed to train patients to eye-estimate meal iP content by "Phosphate Units" (PU), which categorize food components according to iP content (100 mg iP per serving size = 1 PU). To allow self-adjustment of PB dose to meal iP content, a new prescription concept for PB was required. Phosphate binders are no longer prescribed using a fixed dosing regimen but only in strict relation to meal iP content (#PB per PU). In close collaboration with the patient the PB/PU ratio is then adapted to individual patient needs until serum phosphate targets are met. This new management concept for hyperphosphatemia is the first to establish a direct link between dietary phosphorus intake and PB dose and to empower patients to self-adjust PB dose according to dietary phosphorus intake. Clinical studies are under way to establish the practical value of this new concept for CKD and ESRD patients.