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1.
Sci Rep ; 14(1): 17262, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39068299

ABSTRACT

Accurate intraoperative assessment of organ perfusion is a pivotal determinant in preserving organ function e.g. during kidney surgery including partial nephrectomy or kidney transplantation. Hyperspectral imaging (HSI) has great potential to objectively describe and quantify this perfusion as opposed to conventional surrogate techniques such as ultrasound flowmeter, indocyanine green or the subjective eye of the surgeon. An established live porcine model under general anesthesia received median laparotomy and renal mobilization. Different scenarios that were measured using HSI were (1) complete, (2) gradual and (3) partial malperfusion. The differences in spectral reflectance as well as HSI oxygenation (StO2) between different perfusion states were compelling and as high as 56.9% with 70.3% (± 11.0%) for "physiological" vs. 13.4% (± 3.1%) for "venous congestion". A machine learning (ML) algorithm was able to distinguish between these perfusion states with a balanced prediction accuracy of 97.8%. Data from this porcine study including 1300 recordings across 57 individuals was compared to a human dataset of 104 recordings across 17 individuals suggesting clinical transferability. Therefore, HSI is a highly promising tool for intraoperative microvascular evaluation of perfusion states with great advantages over existing surrogate techniques. Clinical trials are required to prove patient benefit.


Subject(s)
Hyperspectral Imaging , Kidney , Animals , Swine , Kidney/blood supply , Kidney/diagnostic imaging , Kidney/surgery , Hyperspectral Imaging/methods , Humans , Artificial Intelligence , Nephrectomy/methods , Perfusion/methods
2.
Int J Surg ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976902

ABSTRACT

INTRODUCTION: Oncologic esophagectomy is a two-cavity procedure with considerable morbidity and mortality. Complex anatomy and the proximity to major vessels constitute a risk for massive intraoperative hemorrhage. Currently, there is no conclusive consensus on the ideal anesthesiologic countermeasure in case of such immense blood loss. The objective of this work was to identify the most promising anesthesiologic management in case of intraoperative hemorrhage with regards to tissue perfusion of the gastric conduit during esophagectomy using hyperspectral imaging (HSI). MATERIAL AND METHODS: An established live porcine model (n=32) for esophagectomy was used with gastric conduit formation and simulation of a linear stapled side-to-side esophagogastrostomy. After a standardized procedure of controlled blood loss of about 1 L per pig, the four experimental groups (n=8 each) differed in anesthesiologic intervention i.e. (I) permissive hypotension, (II) catecholamine therapy using noradrenaline, (III) crystalloid volume supplementation and (IV) combined crystalloid volume supplementation with noradrenaline therapy. HSI tissue oxygenation (StO2) of the gastric conduit was evaluated and correlated with systemic perfusion parameters. Measurements were conducted before (T0) and after (T1) laparotomy, after hemorrhage (T2) and 60 minutes (T3) and 120 minutes (T4) after anesthesiologic intervention. RESULTS: StO2 values of the gastric conduit showed significantly different results between the four experimental groups with 63.3% (±7.6%) after permissive hypotension (I), 45.9% (±6.4%) after catecholamine therapy (II), 70.5% (±6.1%) after crystalloid volume supplementation (III) and 69.0% (±3.7%) after combined therapy (IV). StO2 values correlated strongly with systemic lactate values (r=-0.67; CI -0.77 to -0.54), which is an established prognostic factor. CONCLUSION: Crystalloid volume supplementation (III) yields the highest StO2 values and lowest systemic lactate values and therefore appears to be the superior primary treatment strategy after hemorrhage during esophagectomy with regards to microcirculatory tissue oxygenation of the gastric conduit.

3.
J Dairy Sci ; 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38908702

ABSTRACT

Milk production and overall dairy farm economics depend on rearing dairy heifers. This study investigated the presence of a genotype by environment interaction in Holstein (HOL), Nordic Red Dairy Cattle (RDC), and their F1 crossbreeds (HOLxRDC) when provided different feed rations. The aim of our study was to assess how different energy concentrations in feed rations affect growth, body condition scores, feed intake, and feed efficiency in the 3 groups during the prepubertal period. The 3 breed groups were randomly allocated to receive either a standard or a low energy feed ration. HOL heifers exhibited reduced growth and a lower body condition score when they were fed the low energy feed ration. In contrast, the RDC heifers demonstrated similar growth rates with the different feed rations and maintained similar body condition scores irrespective of feed energy concentration. HOLxRDC crossbred heifers performed as an intermediate between the HOL and RDC groups. There were significant differences in dry matter intake and energy intake in the HOL and HOLxRDC groups depending on feed ration treatment. The RDC heifers had similar feed intake irrespective of treatment. There were no significant differences in the feed conversion ratio between breeds and feed treatments. These results indicate the presence of a genotype by environment interaction in prepubertal HOL and RDC heifers in response to differences in feed ration treatment. Due to the influence of prepubertal growth on future milk production, reproduction, and health status, it is important to be aware of breed-specific requirements during the prepubertal period, particularly in mixed-breed and crossbred groups, to optimize growth rates and production potential.

4.
Surg Endosc ; 38(8): 4316-4328, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38872018

ABSTRACT

BACKGROUND: Laparoscopic cholecystectomy is a very frequent surgical procedure. However, in an ageing society, less surgical staff will need to perform surgery on patients. Collaborative surgical robots (cobots) could address surgical staff shortages and workload. To achieve context-awareness for surgeon-robot collaboration, the intraoperative action workflow recognition is a key challenge. METHODS: A surgical process model was developed for intraoperative surgical activities including actor, instrument, action and target in laparoscopic cholecystectomy (excluding camera guidance). These activities, as well as instrument presence and surgical phases were annotated in videos of laparoscopic cholecystectomy performed on human patients (n = 10) and on explanted porcine livers (n = 10). The machine learning algorithm Distilled-Swin was trained on our own annotated dataset and the CholecT45 dataset. The validation of the model was conducted using a fivefold cross-validation approach. RESULTS: In total, 22,351 activities were annotated with a cumulative duration of 24.9 h of video segments. The machine learning algorithm trained and validated on our own dataset scored a mean average precision (mAP) of 25.7% and a top K = 5 accuracy of 85.3%. With training and validation on our dataset and CholecT45, the algorithm scored a mAP of 37.9%. CONCLUSIONS: An activity model was developed and applied for the fine-granular annotation of laparoscopic cholecystectomies in two surgical settings. A machine recognition algorithm trained on our own annotated dataset and CholecT45 achieved a higher performance than training only on CholecT45 and can recognize frequently occurring activities well, but not infrequent activities. The analysis of an annotated dataset allowed for the quantification of the potential of collaborative surgical robots to address the workload of surgical staff. If collaborative surgical robots could grasp and hold tissue, up to 83.5% of the assistant's tissue interacting tasks (i.e. excluding camera guidance) could be performed by robots.


Subject(s)
Cholecystectomy, Laparoscopic , Machine Learning , Robotic Surgical Procedures , Cholecystectomy, Laparoscopic/methods , Robotic Surgical Procedures/methods , Humans , Swine , Animals , Algorithms , Video Recording , Workflow
5.
J Transcult Nurs ; : 10436596241253863, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38805422

ABSTRACT

INTRODUCTION: To explore the existing research on sexual health experiences of sexual and gender minority women (SGMW) post-curative cancer treatment. METHODOLOGY: This scoping review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews. Four articles that focused on sexual health experiences of SGMW post-curative cancer treatment were included. RESULTS: Four themes were identified: (a) sexual function; (b) sexual orientation and gender identity, including disclosure and health care provider reactions; (c) relationship dynamics, such as relationship status and the quality of romantic relationships; and (d) body image. DISCUSSIONS: The findings underscore substantial challenges faced by SGMW cancer survivors in achieving optimal sexual well-being, impacting their access to post-treatment care. This study advocates for more expansive research efforts involving diverse participant cohorts, extending beyond breast cancer, to gain deeper insights into these critical issues.

6.
Int J Comput Assist Radiol Surg ; 18(7): 1311-1322, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37266886

ABSTRACT

PURPOSE: Validation metrics are a key prerequisite for the reliable tracking of scientific progress and for deciding on the potential clinical translation of methods. While recent initiatives aim to develop comprehensive theoretical frameworks for understanding metric-related pitfalls in image analysis problems, there is a lack of experimental evidence on the concrete effects of common and rare pitfalls on specific applications. We address this gap in the literature in the context of colon cancer screening. METHODS: Our contribution is twofold. Firstly, we present the winning solution of the Endoscopy Computer Vision Challenge on colon cancer detection, conducted in conjunction with the IEEE International Symposium on Biomedical Imaging 2022. Secondly, we demonstrate the sensitivity of commonly used metrics to a range of hyperparameters as well as the consequences of poor metric choices. RESULTS: Based on comprehensive validation studies performed with patient data from six clinical centers, we found all commonly applied object detection metrics to be subject to high inter-center variability. Furthermore, our results clearly demonstrate that the adaptation of standard hyperparameters used in the computer vision community does not generally lead to the clinically most plausible results. Finally, we present localization criteria that correspond well to clinical relevance. CONCLUSION: We conclude from our study that (1) performance results in polyp detection are highly sensitive to various design choices, (2) common metric configurations do not reflect the clinical need and rely on suboptimal hyperparameters and (3) comparison of performance across datasets can be largely misleading. Our work could be a first step towards reconsidering common validation strategies in deep learning-based colonoscopy and beyond.


Subject(s)
Colonic Neoplasms , Deep Learning , Humans , Colonoscopy , Colonic Neoplasms/diagnosis , Image Processing, Computer-Assisted/methods
7.
J Dairy Sci ; 106(8): 5554-5561, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37331869

ABSTRACT

Milk fatty acid composition is gaining interest in the Danish dairy industry both to develop new dairy products and as a management tool. To be able to implement milk fatty acid (FA) composition in the breeding program, it is important to know the correlations with the traits in the breeding goal. To estimate these correlations, we measured milk fat composition in Danish Holstein (DH) and Danish Jersey (DJ) cattle breeds using mid-infrared spectroscopy. Breeding values were estimated for specific FA and for groups of FA. Correlations with the estimated breeding values (EBV) underlying the Nordic Total Merit index (NTM) were calculated within breed. For both DH and DJ, we showed that FA EBV had moderate correlations with the NTM and production traits. For both DH and DJ, the correlation of FA EBV and NTM were in the same direction, except for C16:0 (0 in DH, 0.23 in DJ). A few correlations differed between DH and DJ. The correlation between claw health index and C18:0 was negative in DH (-0.09) but positive in DJ (0.12). In addition, some correlations were not significant in DH but were significant in DJ. The correlations between udder health index and long-chain FA, trans FA, C16:0, and C18:0 were not significant in DH (-0.05 to 0.02), but were significant in DJ (-0.17, -0.15, 0.14, and -0.16, respectively). For both DH and DJ, the correlations between FA EBV and nonproduction traits were low. This implies that it is possible to breed for a different fat composition in the milk without affecting the nonproduction traits in the breeding goal.


Subject(s)
Fatty Acids , Milk , Cattle , Animals , Female , Milk/chemistry , Fatty Acids/analysis , Phenotype , Spectrophotometry, Infrared/veterinary , Denmark , Lactation
8.
Surg Endosc ; 37(8): 6153-6162, 2023 08.
Article in English | MEDLINE | ID: mdl-37145173

ABSTRACT

BACKGROUND: Laparoscopic videos are increasingly being used for surgical artificial intelligence (AI) and big data analysis. The purpose of this study was to ensure data privacy in video recordings of laparoscopic surgery by censoring extraabdominal parts. An inside-outside-discrimination algorithm (IODA) was developed to ensure privacy protection while maximizing the remaining video data. METHODS: IODAs neural network architecture was based on a pretrained AlexNet augmented with a long-short-term-memory. The data set for algorithm training and testing contained a total of 100 laparoscopic surgery videos of 23 different operations with a total video length of 207 h (124 min ± 100 min per video) resulting in 18,507,217 frames (185,965 ± 149,718 frames per video). Each video frame was tagged either as abdominal cavity, trocar, operation site, outside for cleaning, or translucent trocar. For algorithm testing, a stratified fivefold cross-validation was used. RESULTS: The distribution of annotated classes were abdominal cavity 81.39%, trocar 1.39%, outside operation site 16.07%, outside for cleaning 1.08%, and translucent trocar 0.07%. Algorithm training on binary or all five classes showed similar excellent results for classifying outside frames with a mean F1-score of 0.96 ± 0.01 and 0.97 ± 0.01, sensitivity of 0.97 ± 0.02 and 0.0.97 ± 0.01, and a false positive rate of 0.99 ± 0.01 and 0.99 ± 0.01, respectively. CONCLUSION: IODA is able to discriminate between inside and outside with a high certainty. In particular, only a few outside frames are misclassified as inside and therefore at risk for privacy breach. The anonymized videos can be used for multi-centric development of surgical AI, quality management or educational purposes. In contrast to expensive commercial solutions, IODA is made open source and can be improved by the scientific community.


Subject(s)
Artificial Intelligence , Laparoscopy , Humans , Privacy , Laparoscopy/methods , Algorithms , Neural Networks, Computer , Video Recording
9.
Eur J Surg Oncol ; 2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37105869

ABSTRACT

INTRODUCTION: Esophagectomy is the mainstay of esophageal cancer treatment, but anastomotic insufficiency related morbidity and mortality remain challenging for patient outcome. Therefore, the objective of this work was to optimize anastomotic technique and gastric conduit perfusion with hyperspectral imaging (HSI) for total minimally invasive esophagectomy (MIE) with linear stapled anastomosis. MATERIAL AND METHODS: A live porcine model (n = 58) for MIE was used with gastric conduit formation and simulation of linear stapled side-to-side esophagogastrostomy. Four main experimental groups differed in stapling length (3 vs. 6 cm) and simulation of anastomotic position on the conduit (cranial vs. caudal). Tissue oxygenation around the anastomotic simulation site was evaluated using HSI and was validated with histopathology. RESULTS: The tissue oxygenation (ΔStO2) after the anastomotic simulation remained constant only for the short stapler in caudal position (-0.4 ± 4.4%, n.s.) while it was impaired markedly in the other groups (short-cranial: -15.6 ± 11.5%, p = 0.0002; long-cranial: -20.4 ± 7.6%, p = 0.0126; long-caudal: -16.1 ± 9.4%, p < 0.0001). Tissue samples from avascular stomach as measured by HSI showed correspondent eosinophilic pre-necrotic changes in 35.7 ± 9.7% of the surface area. CONCLUSION: Tissue oxygenation at the site of anastomotic simulation of the gastric conduit during MIE is influenced by stapling technique. Optimal oxygenation was achieved with a short stapler (3 cm) and sufficient distance of the simulated anastomosis to the cranial end of the gastric conduit. HSI tissue deoxygenation corresponded to histopathologic necrotic tissue changes. The experimental model with HSI and ML allow for systematic optimization of gastric conduit perfusion and anastomotic technique while clinical translation will have to be proven.

10.
Article in English | MEDLINE | ID: mdl-36385431

ABSTRACT

The tropical carpenter bee, Xylocopa latipes, has metallic-reflecting, iridescent wings. The wing reflectance spectra for TE- and TM-polarized light depend on the angle of light incidence in a way characteristic for dielectric multilayers. Anatomy indicates the presence of melanin multilayers in the wing's chitinous matrix. A simple optical model of melanin multilayers explains the angle dependence of the wing reflectance spectra. The wing reflections that occur upon oblique illumination exhibit colourful and strongly polarized light patterns, which may mediate intraspecific signaling and mutual recognition by conspecifics.


Subject(s)
Iridescence , Melanins , Bees , Animals , Wings, Animal/anatomy & histology
11.
Chirurg ; 93(3): 217-222, 2022 Mar.
Article in German | MEDLINE | ID: mdl-35072742

ABSTRACT

BACKGROUND: Digital systems have increasingly become integrated into the modern operating room in the last few decades. This has brought about a massive change, especially in minimally invasive surgery. OBJECTIVE: The article provides an overview of the current technical innovations and the perspectives of digitalization and artificial intelligence (AI) in surgery. MATERIAL AND METHODS: The article is based on a literature search via PubMed and research work by the participating coauthors. RESULTS: Current research is increasingly looking at machine learning techniques that take advantage of the complex data in surgery; however, the integration of artificial intelligence systems into the operating room and clinical practice has only just begun. DISCUSSION: Translational research of artificial intelligence in surgery is still in its infancy but has great potential to improve patient care; however, to accelerate the incorporation of intelligent systems into the clinical practice, the creation of interdisciplinary research groups led by surgeons is necessary.


Subject(s)
Artificial Intelligence , Surgeons , Forecasting , Humans , Operating Rooms
12.
Zoological Lett ; 6(1): 13, 2020 Nov 12.
Article in English | MEDLINE | ID: mdl-33292721

ABSTRACT

The dorsal wings of male Sasakia charonda butterflies display a striking blue iridescent coloration, which is accentuated by white, orange-yellow and red spots, as well as by brown margins. The ventral wings also have a variegated, but more subdued, pattern. We investigated the optical basis of the various colors of intact wings as well as isolated wing scales by applying light and electron microscopy, imaging scatterometry and (micro)spectrophotometry. The prominent blue iridescence is due to scales with tightly packed, multilayered ridges that contain melanin pigment. The scales in the brown wing margins also contain melanin. Pigments extracted from the orange-yellow and red spots indicate the presence of 3-OH-kynurenine and ommochrome pigment. The scales in the white spots also have multilayered ridges but lack pigment. The lower lamina of the scales plays a so-far undervalued but often crucial role. Its thin-film properties color the majority of the ventral wing scales, which are unpigmented and have large windows. The lower lamina acting as a thin-film reflector generally contributes to the reflectance of the various scale types.

13.
J Insect Physiol ; 127: 104114, 2020.
Article in English | MEDLINE | ID: mdl-32905790

ABSTRACT

The pierid butterfly Colias croceus (Geoffroy in Fourcroy, 1785), established in the Azores archipelago, is polymorphic with six forms, C. croceus f. croceus ♂ and ♀, C. c. f. cremonae ♂ and ♀, C. c. f. helice ♀, and C. c. f. cremonaehelice ♀. We investigated the optical mechanisms underlying the wing colouration of the butterflies by performing spectrophotometry and imaging scatterometry of the variously coloured wing areas and scales. The scale colouration is primarily due to wavelength-selective absorption of incident light by pterins expressed in granular beads in the wing scales, but thin film reflections of the scales' lower lamina and scale stacking also contribute. Three forms (croceus ♂ and ♀ and helice ♀) are consistent with the patterns of the well-known 'alba' polymorphism. We postulate the coexistence of a second polymorphism, 'cremonae', to understand the three other forms (cremonae ♂ and ♀, and cremonaehelice ♀), which are characterized by the absence of red pigment, presumably due to the differential blocking of erythropterin expression.


Subject(s)
Butterflies/physiology , Gene Expression , Polymorphism, Genetic/physiology , Pterins/metabolism , Wings, Animal/chemistry , Animals , Azores , Butterflies/genetics , Female , Male , Pigmentation , Wings, Animal/metabolism
14.
Urologe A ; 59(9): 1035-1043, 2020 Sep.
Article in German | MEDLINE | ID: mdl-32710195

ABSTRACT

The increasing networking of data systems in medicine is not only leading to modern interdisciplinarity in the sense of cooperation between different medical departments, but also poses new challenges regarding the building and room infrastructure. The surgical operating room of the future expands or augments its reality, away from the pure building characteristics, towards an intelligent and communicative space platform. The building infrastructure (operating theatre) serves as sensor and actuator. Thus, it is possible to inform about missing diagnostics as well as to register them directly in the contextualization of the planned surgical intervention or to integrate them into the processes. Integrated operating theatres represent a comprehensive computer platform based on a corresponding system architecture with software-based protocols. An underlying modular system consisting of various modules for image acquisition and analysis, interaction and visualization supports the integration and merging of heterogeneous data that are generated in a hospital operation. Integral building data (e.g., air conditioning, lighting control, device registration) are merged with patient-related data (age, type of illness, concomitant diseases, existing diagnostic CT and MRI images). New systems coming onto the market, as well as already existing systems will have to be measured by the extent to which they will be able to guarantee this integration of information-similar to the development from mobile phone to smartphone. Cost reduction should not be the only legitimizing argument for the market launch, but the vision of a new quality of surgical perception and action.


Subject(s)
General Surgery/trends , Humans , Lighting , Magnetic Resonance Imaging , Operating Rooms
15.
Front Plant Sci ; 11: 600124, 2020.
Article in English | MEDLINE | ID: mdl-33488645

ABSTRACT

Flavonoid pigments are key determinants of flower colors. As absorption spectra of flavonoids are known to be severely pH-dependent, cellular pH will play a crucial role in flower coloration. The flavonoids are concentrated in the vacuoles of the flowers' epidermal cells, and thus the pigments' absorption spectra are modulated by the vacuolar pH. Here we study the pH dependence of flavonoid absorption spectra in extracts from flowers of two poppy species Papaver dubium (red) and Meconopsis cambrica (orange), and a white and red Mandevilla sanderi variety. In the red poppy and Mandevilla flowers, absorption spectra of the cyanidin- and pelargonidin-based anthocyanins peak in the blue-green-wavelength range at low pH, but exhibit a distinct bathochromic shift at higher pH. This shift to longer wavelengths is not found for the blue-absorbing nudicaulin derivatives of M. cambrica, which have a similar absorption spectrum at low and high pH. The pH-dependent absorption changes of the white M. sanderi's flavonoid remained restricted to the UV. An analysis of the spectra with logistic functions suggests that the pH-dependent characteristics of the basic states of flavonols and anthocyanins are related. The implications of tuning of pH and pigment absorption spectra for studies on flower color evolution are discussed.

16.
World J Urol ; 38(2): 447-453, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31073641

ABSTRACT

PURPOSE: To compare iPad-assisted (Apple Inc., Cupertino, USA) percutaneous access to the kidney to the standard puncturing technique for percutaneous nephrolithotomy (PCNL). METHODS: For the iPad-assisted PCNL, a computed tomography is performed prior to surgery, using fiducial radiopaque markers. The important anatomical structures (i.e. kidney, stones) are segmented using specific software enabling the superimposition of images semi-transparently on the iPad by marker-based navigation. Twenty-two patients underwent an iPad-assisted percutaneous puncture of the kidney for PCNL. Twenty-two patients of the clinical database from the Urological Department SLK Hospital Heilbronn, who underwent the standard puncturing technique, were matched to these patients. Matching criteria were age, gender, stone volume, body mass index, stone site and the absence of anatomical variation. Puncture time, radiation exposure and number of attempts for a successful puncture were evaluated. All procedures were performed by two experienced urologists. The standard puncturing method consisted of a combination of ultrasound and fluoroscopy guidance. Chi-square and t test were used to ensure that there was no difference in the matching criteria between the groups. To compare the two methods, U test, Kruskal-Wallis and Chi-square test were used. RESULTS: Examination of radiation exposure showed a significant difference between the two groups in favour of the standard puncturing method (p < 0.01) and puncture time (p = 0.01). However, there was no significant difference in puncturing attempts (p = 0.45). CONCLUSION: The iPad-assisted navigation, with the objective being to puncture the renal collecting system, represents a new technique (IDEAL criteria 2b), which proved to be applicable in clinical practice, but still has potential for technical improvement.


Subject(s)
Computers, Handheld , Kidney Calculi/surgery , Nephrolithotomy, Percutaneous/methods , Surgery, Computer-Assisted/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Matched-Pair Analysis , Middle Aged , Ultrasonography , Young Adult
17.
PeerJ ; 6: e4590, 2018.
Article in English | MEDLINE | ID: mdl-29666756

ABSTRACT

The palm borer moth Paysandisia archon (Castniidae; giant butterfly-moths) has brown dorsal forewings and strikingly orange-coloured dorsal hindwings with white spots surrounded by black margins. Here, we have studied the structure and pigments of the wing scales in the various coloured wing areas, applying light and electron microscopy and (micro)spectrophotometry, and we analysed the spatial reflection properties with imaging scatterometry. The scales in the white spots are unpigmented, those in the black and brown wing areas contain various amounts of melanin, and the orange wing scales contain a blue-absorbing ommochrome pigment. In all scale types, the upper lamina acts as a diffuser and the lower lamina as a thin film interference reflector, with thickness of about 200 nm. Scale stacking plays an important role in creating the strong visual signals: the colour of the white eyespots is created by stacks of unpigmented blue scales, while the orange wing colour is strongly intensified by stacking the orange scales.

18.
J Exp Biol ; 221(Pt 4)2018 02 28.
Article in English | MEDLINE | ID: mdl-29361607

ABSTRACT

The blue secondary and purple-to-green tail feathers of magpies are structurally coloured owing to stacks of hollow, air-containing melanosomes embedded in the keratin matrix of the barbules. We investigated the spectral and spatial reflection characteristics of the feathers by applying (micro)spectrophotometry and imaging scatterometry. To interpret the spectral data, we performed optical modelling, applying the finite-difference time domain (FDTD) method as well as an effective media approach, treating the melanosome stacks as multi-layers with effective refractive indices dependent on the component media. The differently coloured magpie feathers are realised by adjusting the melanosome size, with the diameter of the melanosomes as well as their hollowness being the most sensitive parameters that influence the appearance of the feathers.


Subject(s)
Feathers/physiology , Melanosomes/chemistry , Melanosomes/ultrastructure , Pigmentation/physiology , Songbirds/physiology , Animals , Color , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Models, Chemical , Spectrum Analysis
19.
J Dairy Sci ; 101(3): 2148-2157, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29248226

ABSTRACT

The objective of this study was to assess the genetic variability of the detailed fatty acid (FA) profiles of Danish Holstein (DH) and Danish Jersey (DJ) cattle populations. We estimated genetic parameters for 11 FA or groups of FA in milk samples from the Danish milk control system between May 2015 and October 2016. Concentrations of different FA and FA groups in milk samples were measured by mid-infrared spectroscopy. Data used for parameter estimation were from 132,732 first-parity DH cows and 21,966 first-parity DJ cows. We found the highest heritabilities for test day measurements in both populations for short-chain FA (DH = 0.16; DJ = 0.16) and C16:0 (DH = 0.14; DJ = 0.16). In DH, the highest heritabilities were also found for saturated FA and monounsaturated FA (both populations: 0.15). Genetic correlations between the fatty acid traits showed large differences between DH and DJ for especially short-chain FA with the other FA traits measured. Furthermore, genetic correlations of total fat with monounsaturated FA, polyunsaturated FA, short-chain FA, and C16:0 differed markedly between DH and DJ populations. In conclusion, we found genetic variation in the mid-infrared spectroscopy-predicted FA and FA groups of the DH and DJ cattle populations. This finding opens the possibility of using genetic selection to change the FA profiles of dairy cattle.


Subject(s)
Cattle/genetics , Fatty Acids/analysis , Milk/chemistry , Animals , Denmark , Fatty Acids/genetics , Fatty Acids, Unsaturated/analysis , Female , Genetic Testing , Genetic Variation , Lactation/genetics , Parity , Phenotype , Pregnancy , Spectrophotometry, Infrared
20.
J Environ Manage ; 206: 650-663, 2018 Jan 15.
Article in English | MEDLINE | ID: mdl-29132088

ABSTRACT

There is an increasing interest in considering the effects of air pollution on ecosystem services supply in order to enhance cost-benefit analyses of air pollution policies. This paper presents a generic, conceptual approach that can be used to link atmospheric deposition of air pollutants to ecosystem services supply and societal benefits. The approach is applied in a case study in the Telemark county of Norway. First, we examine the potential effects of four European air quality policy scenarios on N deposition in the ecosystems of this county. Second, we analyse the subsequent impacts on the supply of three ecosystem services: carbon sequestration, timber production and biodiversity. Changes in the supply of the first two services are analysed in both physical and monetary units, biodiversity effects are only analysed in physical terms. The scenarios derive from work conducted in the context of the European National Emissions Ceilings Directive. In the 2010 base case the benefits of carbon sequestration are estimated at 13 million euro per year and the value of timber harvesting at 2.9 million euro per year. Under the examined policy scenarios aiming to reduce nitrogen emissions the societal benefits resulting from these two ecosystem services in Telemark are found to be reduced; the scenarios have little effect on terrestrial biodiversity. Such results cannot be scaled up, individual ecosystem services respond differently to changes in air pollution depending upon type of pollutant, type of ecosystem, type of service, and the magnitude of change. The paper further presents an analysis of the uncertainties that need to be considered in linking air pollution and ecosystem services including those in deposition rates, ecosystem responses, human responses and in the values of ecosystem services. Our conceptual approach is also useful for larger scale analysis of air pollution effects on ecosystem services, for example at national or potentially European scale.


Subject(s)
Air Pollution , Biodiversity , Ecosystem , Air Pollutants , Humans , Norway
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