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Effective antiretroviral treatment of HIV-1, defined as continuously undetectable virus in blood, has substantial effects on the infectiousness and spread of HIV.This paper outlines the assessment of the Swedish Reference Group for Antiviral Therapy (RAV) and Public Health Agency of Sweden regarding contagiousness of HIV-infected persons on antiretroviral therapy (ART).

Small Unmanned Aerial Vehicle (UAV) platforms equipped with compact laser scanners provides a low-cost option for many applications, including surveillance, mapping, and reconnaissance. For these applications, semantic segmentation or semantic labeling of each point in the lidar point cloud, is important for scene-understanding. In this work, we evaluate methods for semantic segmentation of three-dimensional (3D) point clouds of outdoor scenes measured with a laser scanner mounted on a small UAV. We compare the performance of four different semantic segmentation methods, which are all applied in a scan-by-scan fashion, on semi-sparse laser data. The best method achieves 95.3% on the three classes ground, vegetation, and vehicle in terms of mean intersection over union (mIoU) on a previously unseen scene from a different geographical area. The results demonstrate that it is possible to achieve good performance on the semantic segmentation task on data measured using a combination of a small UAV and a compact laser scanner.

BackgroundMost HIV infections originate from individuals who are undiagnosed and unaware of their infection. Estimation of this quantity from surveillance data is hard because there is incomplete knowledge abouti)the time between infection and diagnosis (TI) for the general population andii)the time between immigration and diagnosis for foreign-born persons.DevelopmentWe developed a new statistical method for estimating the number of undiagnosed people living with HIV (PLHIV) and the incidence of HIV-1 based on dynamic modeling of heterogenous HIV-1 surveillance data. We formulated a Bayesian non-linear mixed effects model using multiple biomarkers to estimate TI accounting for biomarker correlation and individual heterogeneities. We explicitly model the probability that an HIV-1 infected foreign-born person was infected either before or after immigration to distinguish between endogenous and exogeneous incidence. The incidence estimator allows for direct calculation of the number of undiagnosed persons.ApplicationThe model was applied to surveillance data in Sweden. The dynamic biomarker model was trained on longitudinal data from 31 treatment-naïve patients with well-defined TI, using CD4 counts, BED serology, polymorphisms in HIV-1polsequences, and testing history. The multiple-biomarker model was more accurate than single biomarkers (mean absolute error 1.01 vs ≥ 1.95). We estimate that 813 (95% CI 780-862) PLHIV were undiagnosed in 2015, representing a proportion of 10.8% (95% CI 10.4-11.3%) of all PLHIV.ConclusionsThe proposed methodology will enhance the utility of standard surveillance data streams and will be useful to monitor progress towards and compliance with the 90-90-90 UNAIDS target.Key messagesCombined heterogeneous HIV-1 surveillance data and biomarker data can be used to estimate both local incidence and the number of undiagnosed people living with HIV.Explicit modeling of the dynamics, heterogeneity, and correlation of multiple biomarkers over time improved estimation of time between infection and diagnosis.Explicit modeling of the probability that foreign-born persons were infected before or after immigration improves accuracy of estimates of endogenous incidence and undiagnosed persons living with HIV.The endogenous incidence of HIV-1 in Sweden is declining, despite continued immigration of HIV-1 infected persons.The proportion of undiagnosed PLHIV decreased over 2010-2015 and was estimated to be 10.8% (95% CI, 10.4-11.3%) in 2015.

Hepatitis B virus (HBV) infection remains a global health threat. The World Health Organization (WHO) established a goal to eliminate HBV infection as a public health threat by 2030, and defined targets for key interventions to achieve that goal. We evaluated HBV burden and relevant national recommendations for progress towards WHO targets in circumpolar countries. Viral hepatitis experts of circumpolar countries were surveyed regarding their country’s burden of HBV, achievement of WHO targets and national public health authority recommendations for HBV prevention and control. Eight of nine circumpolar countries responded. All countries continue to see new HBV infections. Data about HBV prevalence and progress in reaching WHO 2030 elimination targets are lacking. No country was able to report data for all seven WHO target measures. All countries have recommendations targeting the prevention of mother-to-child transmission. Only the USA and Greenland recommend universal birth dose vaccination. Four countries have recommendations to screen persons at high risk for HBV. Existing recommendations largely address prevention; however, recommendations for universal birth dose vaccination have not been widely introduced. Opportunities remain for the development of trackable targets and national elimination planning to screen and treat for HBV to reduce incidence and mortality.

Background Sweden has a low HIV prevalence. However, among new HIV diagnoses in 2016, the proportion of late presenters and migrants was high (59% and 81%, respectively). This poses challenges in estimating the proportion of undiagnosed persons living with HIV (PLHIV). Aim To estimate the proportion of undiagnosed PLHIV in Sweden comparing two models with different demands on data availability and modelling expertise. Methods An individual-based stochastic simulation model of HIV positive populations (SSOPHIE) and the incidence method of the European Centre for Disease Prevention and Control (ECDC) HIV Modelling Tool were applied to clinical, surveillance and migration data from Sweden 1980–2016. Results SSOPHIE estimated that the proportion of undiagnosed PLHIV in 2013 was 26% (n = 2,100; 90% plausibility range (PR): 900–5,000) for all PLHIV, 17% (n = 600; 90% PR: 100–2,000) for men who have sex with men (MSM), 35% in male (n = 300; 90% PR: 200–700) and 34% in female (n = 400; 90% PR: 200–800) migrants from sub-Saharan Africa (SSA). The estimates for the ECDC model in 2013 were 21% (n = 2,013; 95% confidence interval (CI): 1,831–2,189) for all PLHIV, 15% (n = 369; 95% CI: 299–434) for MSM and 21% (n = 530; 95% CI: 436–632) for migrants from SSA. Conclusions The proportion of undiagnosed PLHIV in Sweden is uncertain. SSOPHIE estimates had wide PR. The ECDC model estimates were unreliable because migration was not accounted for. Better migration data and estimation methods are required to obtain reliable estimates of proportions of undiagnosed PLHIV in similar settings.

This work addresses the problem of detecting and classifying materials and targets in hyperspectral images based on their reflectance spectrum. Accurate target detection in hyperspectral imagery requires a radiative transfer model that maps between the spectral reflectance domain and the measured radiance domain. Such a model can be employed in two ways for detection – using atmospheric compensation, where the measured hyperspectral radiance image is converted to a reflectance image, and using forward modeling, where the target reflectance spectrum is converted to an at-sensor target radiance spectrum. This work presents a forward modeling detection method that utilizes in-scene information to estimate the parameters in the radiative transfer model. Uncertainty in the radiative transfer model and variability of the target spectra are captured using a constrained subspace model for the target. Target detection using library spectra and target rediscovery are evaluated in hyperspectral images of a complex urban scene.

Hyperspectral imaging based on a linear variable filter (LVF) close to the focal plane array (FPA) is an attractive technique since it gives a small, lightweight, and inexpensive sensor. Linear variable techniques can capture the full spectrum within a given spectral range in one image at the same time, but only records one wavelength in each pixel. Reconstruction of a spectrum for a point in the scene requires fusion of spectral information from a large number of registered images. We present a procedure to reconstruct a hyperspectral data cube by registering a large number of overlapping images with spectrally varying content using feature-based registration and transforming them to a joint coordinate system. The accuracy of the registration is evaluated and shown to yield a reconstruction error of less than one pixel.

EU/EEA HIV Surveillance Network: Daniela Schmid, André Sasse, Dominique Van Beckhoven, Tonka Varleva, Tatjana Nemeth Blazic, Linos Hadjihannas, Maria Koliou, Marek Maly, Susan Cowan, Kristi Rüütel, Kirsi Liitsola, Mika Salminen, Françoise Cazein, Josiane Pillonel, Florence Lot, Barbara Gunsenheimer-Bartmeyer, Stavros Patrinos, Dimitra Paraskeva, Maria Dudas, Haraldur Briem, Gudrun Sigmundsdottir, Derval Igoe, Kate O'Donnell, Darina O'Flanagan, Barbara Suligoi, Šarlote Konova, Sabine Erne, Irma Caplinskiene, Aurélie Fischer, Jackie Maistre Melillo, Tanya Melillo, Eline Op de Coul, Hans Blystad, Magdalena Rosinska, Isabel Aldir, Helena Cortes Martins, Mariana Mardarescu, Peter Truska, Irena Klavs, Asunción Díaz, Maria Axelsson, Valerie Delpech Helena Cortes Martins: Departamento de Doenças Infeciosas do Instituto Nacional de Saúde Doutor Ricardo Jorge. Background: The HIV burden is increasing in older adults in the European Union (EU) and European Economic Area (EEA). We investigated factors associated with HIV diagnosis in older adults in the 31 EU/EEA countries during a 12 year period. Methods: In this analysis of surveillance data, we compared data from older people (aged ≥50 years) with those from younger people (aged 15–49 years). We extracted new HIV diagnoses reported to the European Surveillance System between Jan 1, 2004, and Dec 31, 2015, and stratified them by age, sex, migration status, transmission route, and CD4 cell count. We defined late diagnosis as CD4 count of less than 350 cells per μL at diagnosis and diagnosis with advanced HIV disease as less than 200 cells per μL. We compared the two age groups with the χ² test for difference, and used linear regression analysis to assess temporal trends. Findings: During the study period 54 102 new HIV diagnoses were reported in older adults. The average notification rate of new diagnoses was 2·6 per 100 000 population across the whole 12 year period, which significantly increased over time (annual average change [AAC] 2·1%, 95% CI 1·1–3·1; p=0·0009). Notification rates for new HIV diagnoses in older adults increased significantly in 16 countries in 2004–15, clustering in central and eastern EU/EEA countries. In 2015, compared with younger adults, older individuals were more likely to originate from the reporting country, to have acquired HIV via heterosexual contact, and to present late (p

Security systems at airports, borders, and other public areas require high throughput screening at the same time as a high level of protection against possible threats is achieved. New safe stand-off systems with automatic detection of concealed objects that operate in the submillimeter wave region are being developed to meet the need for fast screening and respected privacy. These new technologies include radar 3D imaging of moving persons. Real-time fame rates are desired in these scanning radar 3D imaging systems to achieve high throughput. High throughput can also be achieved at lower near real-time frame rates if the 3D images can be motion compensated before detection of concealed objects. In this paper we present a method for motion compensation of submillimeter wave 3D imaging radar data used for security screening. We demonstrate the method on simulated 3D radar data with known motion errors with good results.

Conclusion Kinetic oscillation stimulation (KOS) of nasal mucosa at low frequency seems to be a possibly effective and safe short-term treatment of non-allergic nasal stuffiness. Objective To assess the relief of rhinitis symptoms, especially stuffiness, by comparing active treatment, i.e. KOS at low frequency of the nasal mucosa, with placebo. Methods Patients were randomized to active or placebo treatment in this double-blinded parallel design study. Treatment with an inflatable oscillating catheter was administered on day 0, and symptom scores (stuffiness, secretion, and itching) were graded daily until day 14. An overall grading of symptoms from 1 week before treatment and during 14 days thereafter was made at day 14. Eighty-six patients (52 with non-allergic perennial rhinitis, NAR; 34 with rhinitis medicamentosa, RM) were randomized, and 71 were evaluated (active treatment, n = 35; placebo, n = 36). Results Patients with either NAR or RM who received active treatment reported reduced symptom scores by some measures, e.g. median RQSS stuffiness measure fell from 2 to 1 on a scale from 0 to 3 during the week following treatment. No significant effect was observed for patients treated with placebo. Mild side effects were reported.

In 2014 the Public Health Agency of Sweden and the Swedish Reference Group for Antiviral Therapy (RAV) conducted a review and analysis of the state of knowledge on the duration of follow-up after exposure to human immunodeficiency virus (HIV). Up until then a follow-up of 12 weeks after exposure had been recommended, but improved tests and new information on early diagnosis motivated a re-evaluation of the national recommendations by experts representing infectious diseases and microbiology, county medical officers, the RAV, the Public Health Agency, and other national authorities. Based on the current state of knowledge the Public Health Agency of Sweden and the RAV recommend, starting in April 2015, a follow-up period of 6 weeks after possible HIV-1 exposure, if HIV testing is performed using laboratory-based combination tests detecting both HIV antibody and antigen. If point-of-care rapid HIV tests are used, a follow-up period of 8 weeks is recommended, because currently available rapid tests have insufficient sensitivity for detection of HIV-1 antigen. A follow-up period of 12 weeks is recommended after a possible exposure for HIV-2, since presently used assays do not include HIV-2 antigens and only limited information is available on the development of HIV antibodies during early HIV-2 infection. If pre- or post-exposure prophylaxis is administered, the follow-up period is recommended to begin after completion of prophylaxis. Even if infection cannot be reliably excluded before the end of the recommended follow-up period, HIV testing should be performed at first contact for persons who seek such testing.

A method for determining the water content at the interface between a press felt and a paper web has been developed. The water content was obtained by subtracting the estimated volume of the indent ...

In this paper, we show that the void space in 3D images of paper can be successfully divided into subspaces using digital volume image analysis. The subspaces are denoted pores, which are connected ...

Fast detection and analysis of dangerous substances from longer distances is highly desired in many security applications. Imaging Raman spectroscopy is a novel multi-spectral imaging technique designed for stand-off screening and detection of explosive substances. In this paper we present a method for detection and classification of explosive substances in multi-spectral image sequences from imaging Raman spectroscopy using linear subspace matching. Our approach uses limited spectral information and is computationally efficient, which enables fast screening of interesting areas. The performance of the method is evaluated on real stand-off measurements from a demonstrator system. We show that the method can detect and classify substances with high accuracy.

Surveillance with automated positioning and tracking of subjects and vehicles in 3D is desired in many defence and security applications. Camera systems with stereo or multiple cameras are often used for 3D positioning. In such systems, accurate camera calibration is needed to obtain a reliable 3D position estimate. There is also a need for automated camera calibration to facilitate fast deployment of semi-mobile multi-camera 3D positioning systems. In this paper we investigate a method for automatic calibration of the extrinsic camera parameters (relative camera pose and orientation) of a multi-camera positioning system. It is based on estimation of the essential matrix between each camera pair using the 5-point method for intrinsically calibrated cameras. The method is compared to a manual calibration method using real HD video data from a field trial with a multicamera positioning system. The method is also evaluated on simulated data from a stereo camera model. The results show that the reprojection error of the automated camera calibration method is close to or smaller than the error for the manual calibration method and that the automated calibration method can replace the manual calibration.

Stand-off THz imaging to detect concealed treats is a coming technique for security applications. A THz sensor can provide high resolution 3D imagery of a scene. However, efficient scene scanning and management of the THz sensor is a challenging task due to the limited field of view of the sensor and physical scanning limitations. In this paper we discuss the requirements on a scene scanning solution and present a scene scanning technique using a multi-camera system with 3D positioning capabilities. A visual hull method is used to position subjects in the scene. The presented technique relaxes the requirements on the scanning speed of the THz sensor and facilitates an efficient scene scanning solution.

The development of new asymmetric threats to civilian and naval ships has been a relatively recent occurrence. The bombing of the USS Cole is one example and the pirate activities outside Somalia another. There is a need to recognize targets at long ranges and possibly also their intentions to prepare for counteractions. Eye safe laser imaging at 1.5 μm offers target recognition at long ranges during day and night. The 1.5 μm wavelength is suitable for observing small targets at the sea surface such as boats and swimmers due to the low reflectivity of water compared to potential targets. Turbulence and haze limits the sensor performance and their influence is estimated for some cases of operational interest. For comparison, passive EO images have been recorded with the same camera to investigate the difference between sun illuminated and laser illuminated images. Examples of laser images will be given for a variety of targets and external conditions.Image segmentation for future automated recognition development is described and examplified. Examples of relevant 1.5 μm laser reflectivities of small naval targets are also presented. Finally a discussion of system aspects is made.

Fibre orientation influences many important properties of fibre-based materials, for example, strength and stiffness. Fibre orientation and the orientation anisotropy in paper and other wood fibre-based materials have previously been estimated using two-dimensional images. Recently, we presented a method for estimating the three-dimensional fibre orientation in volume images based on local orientation estimates. Here, we present an evaluation of the method with respect to scale and noise sensitivity. The evaluation is performed for both tubular and solid fibres. We also present a new method for automatic scale selection for solid fibres. The method is based on a segmentation of the fibres that also provides an estimate of the fibre dimension distribution in an image. The results show that the fibre orientation estimation performs well both in noisy images and at different scales. The presented results can be used as a guide to select appropriate parameters for the method when it is applied to real data. The applicability of the fibre orientation estimation to fibre-based materials with solid fibres is demonstrated for a volume image of a press felt acquired with X-ray microtomography.

Fibre orientation is an important structural property of fibre-based materials. For example, in paper the orientation of the fibres influences the dimensional strength of the sheet and the tendency of the sheet to curl and twist at moisture changes. Here, we present a three-dimensional image analysis method for estimating the fibre orientation and the orientation anisotropy. The proposed method can be applied directly to greyscale volume images and is based on local orientation estimates using quadrature filters and structure tensors. From the tensor field the fibre orientation can be estimated together with a corresponding certainty measurement. Good results are obtained for both synthetic fibre data sets and fibre based materials imaged using X-ray microtomography.

Segmentation of individual fibres in volume images is important when analysing the three dimensional (3D) fibre structure in paper and cellulose based composite materials. This paper presents a novel method for 3D tracking of individual fibres which can be used as a pre-segmentation step to a full cell wall segmentation or be used to estimate the fibre orientation. The tracking starts in one seed in each fibre and automatically extracts the local fibre orientation and the fibre centre point in each step using 3D information. Good results are obtained for cellulose fibres that are partially collapsed, cracked or irregularly shaped. The proposed method can also be used in other applications where tracking of tubular structures is of interest.

Ring artifacts can occur in reconstructed images from X-ray microtomography as full or partial circles centred on the rotation axis. In this paper, a 2D method is proposed that reduces these ring artifacts in the reconstructed images. The method consists of two main parts. First, the artifacts are localised in the image using local orientation estimation of the image structures and filtering to find ring patterns in the orientation information. Second, the map of the located artifacts is used to calculate a correction image using normalised convolution. The method is evaluated on 2D images from volume data of paper fibre imaged at the European Synchrotron Radiation Facility (ESRF) with high resolution X-ray microtomography. The results show that the proposed method reduces the artifacts and restores the pixel values for all types of partial and complete ring artifacts where the signal is not completely saturated.