Arnout Ruifrok | Netherlands Forensic Institute (original) (raw)
Papers by Arnout Ruifrok
arXiv (Cornell University), Apr 29, 2023
In forensic facial comparison, questioned-source images are usually captured in uncontrolled envi... more In forensic facial comparison, questioned-source images are usually captured in uncontrolled environments, with nonuniform lighting, and from non-cooperative subjects. The poor quality of such material usually compromises their value as evidence in legal matters. On the other hand, in forensic casework, multiple images of the person of interest are usually available. In this paper, we propose to aggregate deep neural network embeddings from various images of the same person to improve performance in facial verification. We observe significant performance improvements, especially for very low-quality images. Further improvements are obtained by aggregating embeddings of more images and by applying quality-weighted aggregation. We demonstrate the benefits of this approach in forensic evaluation settings with the development and validation of score-based likelihood ratio systems and report improvements in C llr of up to 95% (from 0.249 to 0.012) for CCTV images and of up to 96% (from 0.083 to 0.003) for social media images.
Scientific Reports
Facial recognition errors can jeopardize national security, criminal justice, public safety and c... more Facial recognition errors can jeopardize national security, criminal justice, public safety and civil rights. Here, we compare the most accurate humans and facial recognition technology in a detailed lab-based evaluation and international proficiency test for forensic scientists involving 27 forensic departments from 14 countries. We find striking cognitive and perceptual diversity between naturally skilled super-recognizers, trained forensic examiners and deep neural networks, despite them achieving equivalent accuracy. Clear differences emerged in super-recognizers’ and forensic examiners’ perceptual processing, errors, and response patterns: super-recognizers were fast, biased to respond ‘same person’ and misidentified people with extreme confidence, whereas forensic examiners were slow, unbiased and strategically avoided misidentification errors. Further, these human experts and deep neural networks disagreed on the similarity of faces, pointing to differences in their represent...
2017 5th International Workshop on Biometrics and Forensics (IWBF), 2017
In this paper we study the measurability and variability of manually annotated characteristic des... more In this paper we study the measurability and variability of manually annotated characteristic descriptors on a forensic relevant face dataset. Characteristic descriptors are facial features (landmarks, shapes, etc.) that can be used during forensic case work. With respect to measurability, we observe that a significant proportion cannot be determined in images representative of forensic case work. Landmarks, closed and open shapes, and other forensic facial features show mostly that the variability depends on the image quality. Up to 50% of all considered evidential values are either positively or negatively influenced by annotator variability. However, when considering images with the lowest quality, we found that more than 70% of the evidential value intervals in principle could yield the wrong conclusion.
Forensic Science International, 2022
A simple method is proposed to assess the quality of a trace facial image in the context of the f... more A simple method is proposed to assess the quality of a trace facial image in the context of the facial recognition system used using the similarity scores with low quality different-source facial images, defined as the Confusion Score (CS). Methods are proposed to calculate the probability of finding the correct facial image in a database using low quality images for investigational purposes using the CS, as well as calculation of the Likelihood Ratio (LR) for comparison of low quality trace facial images with good quality reference facial images, based on the assessed CS of the trace image. Improvement of performance of an LR-system using training datasets stratified on CS over the use of pooled data is demonstrated. Examples of using the proposed approach in simulated case examples are presented.
Over the past few years, both large multinationals and governments have begun to contribute to la... more Over the past few years, both large multinationals and governments have begun to contribute to larger projects on biometric devices. Terrorist attacks in the USA and in other countries have highlighted the need for better identification systems for people as well as improved systems for controlling access to buildings. Another reason for investment in Research and Development in biometric devices, is the massive growth in internet-based systems -- whether for e- commerce, e-government or internal processes within organizations. The interface between the system and the user is routinely abused, as people have to remember many complex passwords and handle tokens of various types. In this paper an overview is given of the information that is important to know before an examination of such is systems can be done in a forensic proper way. In forensic evidence with biometric devices the forensic examiner should consider the possibilities of tampering with the biometric systems or the poss...
Facial recognition errors jeopardize national security, criminal justice, public safety and civil... more Facial recognition errors jeopardize national security, criminal justice, public safety and civil rights. Here, we compare the most accurate humans and facial recognition technology in a detailed lab-based evaluation and international proficiency test for forensic scientists involving 27 forensic departments from 14 countries. We find striking cognitive and perceptual diversity between naturally skilled super-recognizers, trained forensic examiners and deep neural networks, despite them achieving equivalent accuracy. Clear differences emerged in super-recognizers’ and forensic examiners’ perceptual processing, errors, and response patterns: super-recognizers were fast, biased to respond ‘same person’ and misidentified people with extreme confidence, whereas forensic examiners were slow, unbiased and strategically avoided misidentification errors. Further, these human experts and algorithms disagreed on the similarity of faces, pointing to differences in their face representations. O...
Het gebruik van warmte bij de behandeling van kanker is al een oud idee. De laatste jaren staat d... more Het gebruik van warmte bij de behandeling van kanker is al een oud idee. De laatste jaren staat de behandeling van tumoren met behulp van 'hyperthermie' weer volop in de belangstelling. Een grote hoeveelheid biologische en klinische gegevens toont aan dat warmte zinvol kan zijn bij de behandeling van kanker. Speciaal in combinatie met straling zijn de resultaten veelbelovend. Ten eerste maakt warmte de cellen stralingsgevoeliger. Ten tweede is een groep cellen die relatief stralingsongevoelig is, namelijk de cellen in slecht doorbloede gebieden die zuurstof-arm zijn, gevoelig voor warmte. Tevens speelt mee dat tumoren door verminderde doorbloeding beter te verwarmen zijn dan normaal, goed doorbloed weefsel. ... Zie: Samenvatting
Forensic Sciences Research, 2018
This review summarizes the scientific basis of forensic gait analysis and evaluates its use in th... more This review summarizes the scientific basis of forensic gait analysis and evaluates its use in the Netherlands, United Kingdom and Denmark, following recent critique on the admission of gait evidence in Canada. A useful forensic feature is (1) measurable, (2) consistent within and (3) different between individuals. Reviewing the academic literature, this article found that (1) forensic gait features can be quantified or observed from surveillance video, but research into accuracy, validity and reliability of these methods is needed; (2) gait is variable within individuals under differing and constant circumstances, with speed having major influence; (3) the discriminative strength of gait features needs more research, although clearly variation exists between individuals. Nevertheless, forensic gait analysis has contributed to several criminal trials in Europe in the past 15 years. The admission of gait evidence differs between courts. The methods are mainly observer-based: multiple gait analysts (independently) assess gait features on video footage of a perpetrator and suspect. Using gait feature databases, likelihood ratios of the hypotheses that the observed individuals have the same or another identity can be calculated. Automated gait recognition algorithms calculate a difference measure between video clips, which is compared with a threshold value derived from a video gait recognition database to indicate likelihood. However, only partly automated algorithms have been used in practice. We argue that the scientific basis of forensic gait analysis is limited. However, gait feature databases enable its use in court for supportive evidence with relatively low evidential value. The recommendations made in this review are (1) to expand knowledge on inter-and intra-subject gait variabilities, discriminative strength and interdependency of gait features, method accuracies, gait feature databases and likelihood ratio estimations; (2) to compare automated and observer-based gait recognition methods; to design (3) an international standard method with known validity, reliability and proficiency tests for analysts; (4) an international standard gait feature data collection method resulting in database(s); (5) (inter)national guidelines for the admission of gait evidence in court; and (6) to decrease the risk for cognitive and contextual bias in forensic gait analysis. This is expected to improve admission of gait evidence in court and judgment of its evidential value. Several ongoing research projects focus on parts of these recommendations.
Radiation Research: A Twentieth-century Perspective, 1991
Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology, 1997
Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, wh... more Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, which is the proliferative unit of the colon. Accurate quantitative and spatial analyses of S phase cells in the colon have therefore been limited by histological techniques. To overcome these limitations, S phase cells in microdissected intact colonic crypts of control, modified-starved, and refed rats were labeled by histone H3 in situ hybridization and analyzed by confocal microscopy. High-resolution digital images of the crypt cell nuclei stained with cyanine nucleic acid and of the labeled S phase cells were produced from confocal microscopic optical crypt sections. The S phase labeling index (LI) per whole crypt significantly (P < 0.001) discriminated the proliferative differences between control, modified-starved, and refed rats and correlated (r = 0.92) with the LI determined from histological crypt sections of the same rats. The variance component of the LI attributable to diff...
Radiation Research, 1996
Retinoic acid (RA) and the drug carrier dimethylsulfoxide (DMSO) have been shown to reduce cellul... more Retinoic acid (RA) and the drug carrier dimethylsulfoxide (DMSO) have been shown to reduce cellular radiation sensitivity in vitro because of their hydroxyl radical scavenging properties. Both agents have also been shown to induce differentiation in vitro and in vivo. As intestinal crypts are multicellular systems, crypt survival after irradiation depends not only on the cellular sensitivity of the clonogenic cells, but also on the number of clonogenic cells in each crypt, which may be changed by treatments with agents which induce differentiation. In the present experiments we examined the effects of DMSO and RA on the radiosensitivity of mouse jejunal crypts in vivo using the microcolony assay. Mice were treated with five daily intraperitoneal doses of 0-500 microgram RA in 0.1 ml DMSO per mouse, the last dose applied 4 h before the start of irradiation. The results showed a clear protection by 100 and 500 micrograms/day RA in 0.1 ml DMSO for crypt survival over the dose range of 9-16 Gy. The D0 was increased from 1.30 Gy for untreated controls to 1.59 Gy after treatment with DMSO alone, and to 1.85 Gy after treatment with 100 micrograms/day RA in DMSO. Split-dose experiments showed a reduction in the number of clonogens by a factor of about 2 from DMSO treatment alone, with no additional effect of RA on the number of clonogens. Despite this reduction, the number of BrdUrd-labeled cells per crypt remained roughly the same, as did the count of cells per longitudinal villus section. We conclude that, in addition to the protective effects of RA in DMSO, there is induced differentiation of crypt clonogens which is counteracted by increased proliferative activity of transit cells with the result that villus cellularity is maintained.
European Journal of Cancer, 1993
Iutrathecal treatment with cytosine arabinoside @a-C) in combination with radiation has been used... more Iutrathecal treatment with cytosine arabinoside @a-C) in combination with radiation has been used as prophylactic treatment in children with acute lymphatic leukaemia. Animal experiments have shown that ara-C enhances the effect of radiation on the spinal cord when administered shortly before irradiation, and that the longterm recovery after a combined treatment may be impaired. In the present experiments immature, 3-week-old rats, were treated with ara-C and radiation on the cervical spinal cord, and the long-term recovery was examined by &radiation after different intervals. The endpoint of the study was paresis due to radiation myelopathy. The results showed a clear enhancement of the radiation effect with a dose-modifying factor of 1.2, when ara-C was administered before irradiation. However, no indications for impaired long-term recovery were observed. Additional experiments in adult rats with ara-C treatments during a 6-month interval between two radiation doses also did not suggest any interference between ara-C treatment and long-term recovery of radiation induced injury. It is concluded that for both the adult and immature nervous tissue, only when ara-C is administered intraspinahy shortly before irradiation, interaction between ara-C and radiation results in a significant reduction of the isoeffective radiation dose by a factor of 1.2 (1.1~1.37,95% confidence interval).
Forensic science review, 2018
This paper surveys the literature on forensic face recognition (FFR), with a particular focus on ... more This paper surveys the literature on forensic face recognition (FFR), with a particular focus on the strength of evidence as used in a court of law. FFR is the use of biometric face recognition for several applications in forensic science. It includes scenarios of ID verification and open-set identification, investigation and intelligence, and evaluation of the strength of evidence. We present FFR from operational, tactical, and strategic perspectives. We discuss criticism of FFR and we provide an overview of research efforts from multiple perspectives that relate to the domain of FFR. Finally, we sketch possible future directions for FFR.
Disclaimer/Complaints regulations If you believe that digital publication of certain material inf... more Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible.
In this review, the most important developments are presented for the following general fields of... more In this review, the most important developments are presented for the following general fields of expertise: : (1) Biometric analysis of image material, (2) Detection of image manipulation, (3) Camera source identification, (4) Video image processing and Image search.
Forensic Science International: Synergy
Radiation research, 1997
The goal of the present study was to assess changes in proliferation in the mouse jejunum after i... more The goal of the present study was to assess changes in proliferation in the mouse jejunum after irradiation and the role of the growth factors EGF, TGF-alpha and TGF-beta 1-3 in the proliferative response. Our working hypothesis was that feedback signals from the villus to cells in the crypt regulate proliferation, and that the growth factors EGF and TGF-alpha with their common receptor EGF-R are involved in stimulation of proliferation, while the growth factors TGF-beta 1-3 with their receptors TGF-beta RI and TGF-beta RII are involved in inhibition of proliferation during this regulation. Immunohistochemical detection methods and automated image analysis were used for objective quantification of growth factor expression. The data indicate that, after 5 Gy irradiation, growth stimulation in the crypts takes place before major changes in the villi are observed. However, the combination of the reduction in the cell number, the number of cells expressing TGF-beta 1-3 and the reduction...
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, 1992
The dose dependence and time course of long-term recovery in the cervical spinal cord of 3-week-o... more The dose dependence and time course of long-term recovery in the cervical spinal cord of 3-week-old rats was investigated, and compared with the recovery in adults rats. At intervals of 1 to 168 days after initial irradiation of the cervical spinal cord at the age of 3 weeks, reirradiation experiments were performed to test the pattern of long-term recovery in immature spinal cord. The single dose ED50 for white matter mediated paresis was about 21 Gy for 3-week-old as well as adult rats, although the latency to paresis development increased from about 90 days in 3-week-old rats to about 250 days in adult rats. The main long-term recovery was seen during the first month after the initial radiation treatment at 3 weeks. This is in contrast to long-term recovery in adult rats, in which the main recovery took place between 2 and 6 months after the first irradiation. Calculations according to the LQ model showed that the extra dose that can be given to the cervical spinal cord after a 1...
Interpol's Forensic Science Review, 2010
arXiv (Cornell University), Apr 29, 2023
In forensic facial comparison, questioned-source images are usually captured in uncontrolled envi... more In forensic facial comparison, questioned-source images are usually captured in uncontrolled environments, with nonuniform lighting, and from non-cooperative subjects. The poor quality of such material usually compromises their value as evidence in legal matters. On the other hand, in forensic casework, multiple images of the person of interest are usually available. In this paper, we propose to aggregate deep neural network embeddings from various images of the same person to improve performance in facial verification. We observe significant performance improvements, especially for very low-quality images. Further improvements are obtained by aggregating embeddings of more images and by applying quality-weighted aggregation. We demonstrate the benefits of this approach in forensic evaluation settings with the development and validation of score-based likelihood ratio systems and report improvements in C llr of up to 95% (from 0.249 to 0.012) for CCTV images and of up to 96% (from 0.083 to 0.003) for social media images.
Scientific Reports
Facial recognition errors can jeopardize national security, criminal justice, public safety and c... more Facial recognition errors can jeopardize national security, criminal justice, public safety and civil rights. Here, we compare the most accurate humans and facial recognition technology in a detailed lab-based evaluation and international proficiency test for forensic scientists involving 27 forensic departments from 14 countries. We find striking cognitive and perceptual diversity between naturally skilled super-recognizers, trained forensic examiners and deep neural networks, despite them achieving equivalent accuracy. Clear differences emerged in super-recognizers’ and forensic examiners’ perceptual processing, errors, and response patterns: super-recognizers were fast, biased to respond ‘same person’ and misidentified people with extreme confidence, whereas forensic examiners were slow, unbiased and strategically avoided misidentification errors. Further, these human experts and deep neural networks disagreed on the similarity of faces, pointing to differences in their represent...
2017 5th International Workshop on Biometrics and Forensics (IWBF), 2017
In this paper we study the measurability and variability of manually annotated characteristic des... more In this paper we study the measurability and variability of manually annotated characteristic descriptors on a forensic relevant face dataset. Characteristic descriptors are facial features (landmarks, shapes, etc.) that can be used during forensic case work. With respect to measurability, we observe that a significant proportion cannot be determined in images representative of forensic case work. Landmarks, closed and open shapes, and other forensic facial features show mostly that the variability depends on the image quality. Up to 50% of all considered evidential values are either positively or negatively influenced by annotator variability. However, when considering images with the lowest quality, we found that more than 70% of the evidential value intervals in principle could yield the wrong conclusion.
Forensic Science International, 2022
A simple method is proposed to assess the quality of a trace facial image in the context of the f... more A simple method is proposed to assess the quality of a trace facial image in the context of the facial recognition system used using the similarity scores with low quality different-source facial images, defined as the Confusion Score (CS). Methods are proposed to calculate the probability of finding the correct facial image in a database using low quality images for investigational purposes using the CS, as well as calculation of the Likelihood Ratio (LR) for comparison of low quality trace facial images with good quality reference facial images, based on the assessed CS of the trace image. Improvement of performance of an LR-system using training datasets stratified on CS over the use of pooled data is demonstrated. Examples of using the proposed approach in simulated case examples are presented.
Over the past few years, both large multinationals and governments have begun to contribute to la... more Over the past few years, both large multinationals and governments have begun to contribute to larger projects on biometric devices. Terrorist attacks in the USA and in other countries have highlighted the need for better identification systems for people as well as improved systems for controlling access to buildings. Another reason for investment in Research and Development in biometric devices, is the massive growth in internet-based systems -- whether for e- commerce, e-government or internal processes within organizations. The interface between the system and the user is routinely abused, as people have to remember many complex passwords and handle tokens of various types. In this paper an overview is given of the information that is important to know before an examination of such is systems can be done in a forensic proper way. In forensic evidence with biometric devices the forensic examiner should consider the possibilities of tampering with the biometric systems or the poss...
Facial recognition errors jeopardize national security, criminal justice, public safety and civil... more Facial recognition errors jeopardize national security, criminal justice, public safety and civil rights. Here, we compare the most accurate humans and facial recognition technology in a detailed lab-based evaluation and international proficiency test for forensic scientists involving 27 forensic departments from 14 countries. We find striking cognitive and perceptual diversity between naturally skilled super-recognizers, trained forensic examiners and deep neural networks, despite them achieving equivalent accuracy. Clear differences emerged in super-recognizers’ and forensic examiners’ perceptual processing, errors, and response patterns: super-recognizers were fast, biased to respond ‘same person’ and misidentified people with extreme confidence, whereas forensic examiners were slow, unbiased and strategically avoided misidentification errors. Further, these human experts and algorithms disagreed on the similarity of faces, pointing to differences in their face representations. O...
Het gebruik van warmte bij de behandeling van kanker is al een oud idee. De laatste jaren staat d... more Het gebruik van warmte bij de behandeling van kanker is al een oud idee. De laatste jaren staat de behandeling van tumoren met behulp van 'hyperthermie' weer volop in de belangstelling. Een grote hoeveelheid biologische en klinische gegevens toont aan dat warmte zinvol kan zijn bij de behandeling van kanker. Speciaal in combinatie met straling zijn de resultaten veelbelovend. Ten eerste maakt warmte de cellen stralingsgevoeliger. Ten tweede is een groep cellen die relatief stralingsongevoelig is, namelijk de cellen in slecht doorbloede gebieden die zuurstof-arm zijn, gevoelig voor warmte. Tevens speelt mee dat tumoren door verminderde doorbloeding beter te verwarmen zijn dan normaal, goed doorbloed weefsel. ... Zie: Samenvatting
Forensic Sciences Research, 2018
This review summarizes the scientific basis of forensic gait analysis and evaluates its use in th... more This review summarizes the scientific basis of forensic gait analysis and evaluates its use in the Netherlands, United Kingdom and Denmark, following recent critique on the admission of gait evidence in Canada. A useful forensic feature is (1) measurable, (2) consistent within and (3) different between individuals. Reviewing the academic literature, this article found that (1) forensic gait features can be quantified or observed from surveillance video, but research into accuracy, validity and reliability of these methods is needed; (2) gait is variable within individuals under differing and constant circumstances, with speed having major influence; (3) the discriminative strength of gait features needs more research, although clearly variation exists between individuals. Nevertheless, forensic gait analysis has contributed to several criminal trials in Europe in the past 15 years. The admission of gait evidence differs between courts. The methods are mainly observer-based: multiple gait analysts (independently) assess gait features on video footage of a perpetrator and suspect. Using gait feature databases, likelihood ratios of the hypotheses that the observed individuals have the same or another identity can be calculated. Automated gait recognition algorithms calculate a difference measure between video clips, which is compared with a threshold value derived from a video gait recognition database to indicate likelihood. However, only partly automated algorithms have been used in practice. We argue that the scientific basis of forensic gait analysis is limited. However, gait feature databases enable its use in court for supportive evidence with relatively low evidential value. The recommendations made in this review are (1) to expand knowledge on inter-and intra-subject gait variabilities, discriminative strength and interdependency of gait features, method accuracies, gait feature databases and likelihood ratio estimations; (2) to compare automated and observer-based gait recognition methods; to design (3) an international standard method with known validity, reliability and proficiency tests for analysts; (4) an international standard gait feature data collection method resulting in database(s); (5) (inter)national guidelines for the admission of gait evidence in court; and (6) to decrease the risk for cognitive and contextual bias in forensic gait analysis. This is expected to improve admission of gait evidence in court and judgment of its evidential value. Several ongoing research projects focus on parts of these recommendations.
Radiation Research: A Twentieth-century Perspective, 1991
Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology, 1997
Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, wh... more Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, which is the proliferative unit of the colon. Accurate quantitative and spatial analyses of S phase cells in the colon have therefore been limited by histological techniques. To overcome these limitations, S phase cells in microdissected intact colonic crypts of control, modified-starved, and refed rats were labeled by histone H3 in situ hybridization and analyzed by confocal microscopy. High-resolution digital images of the crypt cell nuclei stained with cyanine nucleic acid and of the labeled S phase cells were produced from confocal microscopic optical crypt sections. The S phase labeling index (LI) per whole crypt significantly (P < 0.001) discriminated the proliferative differences between control, modified-starved, and refed rats and correlated (r = 0.92) with the LI determined from histological crypt sections of the same rats. The variance component of the LI attributable to diff...
Radiation Research, 1996
Retinoic acid (RA) and the drug carrier dimethylsulfoxide (DMSO) have been shown to reduce cellul... more Retinoic acid (RA) and the drug carrier dimethylsulfoxide (DMSO) have been shown to reduce cellular radiation sensitivity in vitro because of their hydroxyl radical scavenging properties. Both agents have also been shown to induce differentiation in vitro and in vivo. As intestinal crypts are multicellular systems, crypt survival after irradiation depends not only on the cellular sensitivity of the clonogenic cells, but also on the number of clonogenic cells in each crypt, which may be changed by treatments with agents which induce differentiation. In the present experiments we examined the effects of DMSO and RA on the radiosensitivity of mouse jejunal crypts in vivo using the microcolony assay. Mice were treated with five daily intraperitoneal doses of 0-500 microgram RA in 0.1 ml DMSO per mouse, the last dose applied 4 h before the start of irradiation. The results showed a clear protection by 100 and 500 micrograms/day RA in 0.1 ml DMSO for crypt survival over the dose range of 9-16 Gy. The D0 was increased from 1.30 Gy for untreated controls to 1.59 Gy after treatment with DMSO alone, and to 1.85 Gy after treatment with 100 micrograms/day RA in DMSO. Split-dose experiments showed a reduction in the number of clonogens by a factor of about 2 from DMSO treatment alone, with no additional effect of RA on the number of clonogens. Despite this reduction, the number of BrdUrd-labeled cells per crypt remained roughly the same, as did the count of cells per longitudinal villus section. We conclude that, in addition to the protective effects of RA in DMSO, there is induced differentiation of crypt clonogens which is counteracted by increased proliferative activity of transit cells with the result that villus cellularity is maintained.
European Journal of Cancer, 1993
Iutrathecal treatment with cytosine arabinoside @a-C) in combination with radiation has been used... more Iutrathecal treatment with cytosine arabinoside @a-C) in combination with radiation has been used as prophylactic treatment in children with acute lymphatic leukaemia. Animal experiments have shown that ara-C enhances the effect of radiation on the spinal cord when administered shortly before irradiation, and that the longterm recovery after a combined treatment may be impaired. In the present experiments immature, 3-week-old rats, were treated with ara-C and radiation on the cervical spinal cord, and the long-term recovery was examined by &radiation after different intervals. The endpoint of the study was paresis due to radiation myelopathy. The results showed a clear enhancement of the radiation effect with a dose-modifying factor of 1.2, when ara-C was administered before irradiation. However, no indications for impaired long-term recovery were observed. Additional experiments in adult rats with ara-C treatments during a 6-month interval between two radiation doses also did not suggest any interference between ara-C treatment and long-term recovery of radiation induced injury. It is concluded that for both the adult and immature nervous tissue, only when ara-C is administered intraspinahy shortly before irradiation, interaction between ara-C and radiation results in a significant reduction of the isoeffective radiation dose by a factor of 1.2 (1.1~1.37,95% confidence interval).
Forensic science review, 2018
This paper surveys the literature on forensic face recognition (FFR), with a particular focus on ... more This paper surveys the literature on forensic face recognition (FFR), with a particular focus on the strength of evidence as used in a court of law. FFR is the use of biometric face recognition for several applications in forensic science. It includes scenarios of ID verification and open-set identification, investigation and intelligence, and evaluation of the strength of evidence. We present FFR from operational, tactical, and strategic perspectives. We discuss criticism of FFR and we provide an overview of research efforts from multiple perspectives that relate to the domain of FFR. Finally, we sketch possible future directions for FFR.
Disclaimer/Complaints regulations If you believe that digital publication of certain material inf... more Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible.
In this review, the most important developments are presented for the following general fields of... more In this review, the most important developments are presented for the following general fields of expertise: : (1) Biometric analysis of image material, (2) Detection of image manipulation, (3) Camera source identification, (4) Video image processing and Image search.
Forensic Science International: Synergy
Radiation research, 1997
The goal of the present study was to assess changes in proliferation in the mouse jejunum after i... more The goal of the present study was to assess changes in proliferation in the mouse jejunum after irradiation and the role of the growth factors EGF, TGF-alpha and TGF-beta 1-3 in the proliferative response. Our working hypothesis was that feedback signals from the villus to cells in the crypt regulate proliferation, and that the growth factors EGF and TGF-alpha with their common receptor EGF-R are involved in stimulation of proliferation, while the growth factors TGF-beta 1-3 with their receptors TGF-beta RI and TGF-beta RII are involved in inhibition of proliferation during this regulation. Immunohistochemical detection methods and automated image analysis were used for objective quantification of growth factor expression. The data indicate that, after 5 Gy irradiation, growth stimulation in the crypts takes place before major changes in the villi are observed. However, the combination of the reduction in the cell number, the number of cells expressing TGF-beta 1-3 and the reduction...
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, 1992
The dose dependence and time course of long-term recovery in the cervical spinal cord of 3-week-o... more The dose dependence and time course of long-term recovery in the cervical spinal cord of 3-week-old rats was investigated, and compared with the recovery in adults rats. At intervals of 1 to 168 days after initial irradiation of the cervical spinal cord at the age of 3 weeks, reirradiation experiments were performed to test the pattern of long-term recovery in immature spinal cord. The single dose ED50 for white matter mediated paresis was about 21 Gy for 3-week-old as well as adult rats, although the latency to paresis development increased from about 90 days in 3-week-old rats to about 250 days in adult rats. The main long-term recovery was seen during the first month after the initial radiation treatment at 3 weeks. This is in contrast to long-term recovery in adult rats, in which the main recovery took place between 2 and 6 months after the first irradiation. Calculations according to the LQ model showed that the extra dose that can be given to the cervical spinal cord after a 1...
Interpol's Forensic Science Review, 2010