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Planck is the third generation of mm-wave instruments designed for space observations of the cosmic microwave background (CMB) anisotropies within the new Cosmic Vision 2020 ESA Science Program. Planck will map the whole sky with unprecedented sensitivity, angular resolution, and frequency coverage, and it likely leads us to the final comprehension of the CMB anisotropies. The Low Frequency Instrument (LFI), operating in the 30-70 GHz range, is one of the two instruments onboard Planck satellite, sharing the focal region of a 1.5 meter off-axis dual reflector telescope together with the High Frequency Instrument (HFI) operating at 100-857 GHz. We present LFI and discuss the major instrumental systematic effects that could degrade the measurements and the solutions adopted in the design and data analysis phase in order to adequately reduce and control them., 5 pages, 1 figure, On behalf of LFI Consortium,to be published in proc. JENAM 2004 meeting "The many scales in the Universe", Granada, Spain, 13-17 Sept. 2004

Acquired Neglect Dyslexia is often associated with right-hemisphere brain damage and is mainly characterized by omissions and substitutions in reading single words. Martelli et al. proposed in 2011 that these two types of error are due to different mechanisms. Omissions should depend on neglect plus an oculomotor deficit, whilst substitutions on the difficulty with which the letters are perceptually segregated from each other (i.e., crowding phenomenon). In this study, we hypothesized that a deficit of focal attention could determine a pathological crowding effect, leading to imprecise letter identification and consequently substitution errors. In Experiment 1, three brain-damaged patients, suffering from peripheral dyslexia, mainly characterized by substitutions, underwent an assessment of error distribution in reading pseudowords and a T detection task as a function of cue size and timing, in order to measure focal attention. Each patient, when compared to a control group, showed a deficit in adjusting the attentional focus. In Experiment 2, a group of 17 right-brain-damaged patients were asked to perform the focal attention task and to read single words and pseudowords as a function of inter-letter spacing. The results allowed us to confirm a more general association between substitution-type reading errors and the performance in the focal attention task.

Prosopagnosia is a disorder leading to difficulties in recognizing faces. However, recent evidence suggests that individuals with congenital prosopagnosia can achieve considerable accuracy when they have to recognize their own faces (self-face advantage). Yet, whether this advantage is face-specific or not is still unclear. Here, we aimed to investigate whether individuals with congenital prosopagnosia show a self-advantage also in recognizing other self body-parts and, if so, whether the advantage for the body parts differs from the one characterizing the self-face. Eight individuals with congenital prosopagnosia and 22 controls underwent a delayed matching task in which they were required to recognize faces, hands, and feet belonging to the self or to others. Controls showed a similar self-advantage for all the stimuli tested; by contrast, individuals with congenital prosopagnosia showed a larger self-advantage with faces compared to hands and feet, mainly driven by their deficit with others’ faces. In both groups the self-advantages for the different body parts were strongly and significantly correlated. Our data suggest that the self-face advantage showed by individuals with congenital prosopagnosia is not face-specific and that the same mechanism could be responsible for both the self-face and self body-part advantages.

Objective Recent evidence showed that individuals with congenital face processing impairment (congenital prosopagnosia [CP]) are highly accurate when they have to recognize their own face (self-face advantage) in an implicit matching task, with a preference for the right-half of the self-face (right perceptual bias). Yet the perceptual strategies underlying this advantage are unclear. Here, we aimed to verify whether both the self-face advantage and the right perceptual bias emerge in an explicit task, and whether those effects are linked to a different scanning strategy between the self-face and unfamiliar faces. Method Eye movements were recorded from 7 CPs and 13 controls, during a self/other discrimination task of stimuli depicting the self-face and another unfamiliar face, presented upright and inverted. Results Individuals with CP and controls differed significantly in how they explored faces. In particular, compared with controls, CPs used a distinct eye movement sampling strategy for processing inverted faces, by deploying significantly more fixations toward the nose and mouth areas, which resulted in more efficient recognition. Moreover, the results confirmed the presence of a self-face advantage in both groups, but the eye movement analyses failed to reveal any differences in the exploration of the self-face compared with the unfamiliar face. Finally, no bias toward the right-half of the self-face was found. Conclusions Our data suggest that the self-face advantage emerges both in implicit and explicit recognition tasks in CPs as much as in good recognizers, and it is not linked to any specific visual exploration strategies. (PsycINFO Database Record

Objective The lack of inversion effect for face recognition in congenital prosopagnosia (CP) is consistent with the hypothesis of a failure in holistic processing. However, although CPs' abnormal gaze behavior for upright faces has already been demonstrated, neither their scanning strategy for inverted faces, nor the possibility that their abnormal gaze behavior with upright faces is because of reasons other than the holistic deficit have been investigated yet. Method We recorded the eye movements of a congenital prosopagnosic and a control group during the encoding of unknown faces, objects, and flowers. Two types of stimuli (faces and objects) were presented upright and inverted. Results CPs explored upright and inverted faces in the same way (i.e., similar number of fixations of the same duration and similarly distributed), whereas controls increased the number of fixations and their duration during the presentation of inverted faces. By contrast, the 2 groups showed a similar inversion effect during the encoding of objects. Finally, CPs showed anomalous exploration of within-class objects (i.e., flowers) and impairment in subordinate-level object discrimination. Conclusions Our results demonstrate that: (a) CPs use the same part-based strategy in encoding both upright and inverted faces, suggesting a possible interpretation of the lack of inversion effect in this population; (b) CPs' lack of inversion effect is face-specific and does not affect objects; (c) however, CPs' deficit seems not to be limited to faces, and to extend to individual-item recognition within a class. (PsycINFO Database Record

To evaluate the impact of faecal immunochemical test (FIT) screening on stage distribution at diagnosis, and to estimate relative incidence rates by stage in screened at first and subsequent rounds vs. unscreened. We included all incident cases occurring in 2000-2008 in 50- to 71-year-olds residing in areas with an FIT-screening programme. Multinomial logistic models were computed to estimate the relative risk ratio (RRR) of stages I and IV, compared to stage II + III, adjusting for age, sex, geographical area, and incidence year. Proportions were then used to estimate incidence rate ratios (IRR) by stage for screened subjects at the first and at subsequent rounds vs. unscreened subjects, applying the expected changes in overall incidence during screening phases. 11,663 cancers were included: 5965 in not-invited and 5,698 in invited subjects, 3,425 of whom attendees. Compared to not-invited, invited subjects had RRR 2.04 (95% CI: 1.84; 2.46) of stage I and RRR 0.77 (95% CI: 0.69; 0.87) of stage IV. Differences were stronger comparing attendees vs. nonattendees. Interval cancers were more frequently stage I compared to non-invited (RRR 1.54; 95% CI: 1.15; 2.04), but there was no difference for stage IV. IRRs in screened at first round vs. unscreened were 4.6 (95% CI: 4.2; 5.1), 1.4 (95% CI: 1.3; 1.5) and 0.7 (95% CI: 0.6; 0.9) for stages I, II + III and IV, respectively; in the following rounds the IRRs of screened vs. unscreened were 1.4 (95% CI: 1.2; 1.6), 0.8 (95% CI: 0.7; 0.9) and 0.3 (95% CI: 0.1; 0.4) for stages I, II + III and IV, respectively. FIT screening reduces the incidence of metastatic cancers by about 70% after the first round.

The existence of a drift to base judgments more on the right half-part of facial stimuli, which falls in the observer's left visual field (left perceptual bias (LPB)), in normal individuals has been demonstrated. However, less is known about the existence of this phenomenon in people affected by face impairment from birth, namely congenital prosopagnosics. In the current study, we aimed to investigate the presence of the LPB under face impairment conditions using chimeric stimuli and the most familiar face of all: the self-face. For this purpose we tested 10 participants with congenital prosopagnosia and 21 healthy controls with a face matching task using facial stimuli, involving a spatial manipulation of the left and the right hemi-faces of self-photos and photos of others. Even though congenital prosopagnosics performance was significantly lower than that of controls, both groups showed a consistent self-face advantage. Moreover, congenital prosopagnosics showed optimal performance when the right side of their face was presented, that is, right perceptual bias, suggesting a differential strategy for self-recognition in those subjects. A possible explanation for this result is discussed.

Focusing attention on a limited space within the environment allows us to concentrate our resources selectively on that location while ignoring the rest of the space. In this study we investigated how the deployment of the focal attention in foveal vision can be affected by task and stimuli specificity. In particular, we measured the cue-size effect in four experiments: shape detection (Experiment 1), shape discrimination (Experiment 2), letter detection (Experiment 3), and letter discrimination (Experiment 4). Our results highlight that, although the focal component can be elicited by different tasks (i.e., detection or discrimination) and by using different types of stimuli (i.e., shapes or letters), those effects interact with each other. Specifically, the effect of focal attention is more noticeable when letter stimuli are used in the case of a detection task, while no difference between letters and geometrical shapes is observed in the discrimination task. Furthermore, the analysis of the cue-size effect across the four experiments confirmed that the deployment of focal attention in foveal vision is mainly reflexive.

The Benton Facial Recognition Test (BFRT) and Cambridge Face Memory Test (CFMT) are two of the most common tests used to assess face discrimination and recognition abilities and to identify individuals with prosopagnosia. However, recent studies highlighted that participant-stimulus match ethnicity, as much as gender, has to be taken into account in interpreting results from these tests. Here, in order to obtain more appropriate normative data for an Italian sample, the CFMT and BFRT were administered to a large cohort of young adults. We found that scores from the BFRT are not affected by participants' gender and are only slightly affected by participant-stimulus ethnicity match, whereas both these factors seem to influence the scores of the CFMT. Moreover, the inclusion of a sample of individuals with suspected face recognition impairment allowed us to show that the use of more appropriate normative data can increase the BFRT efficacy in identifying individuals with face discrimination impairments; by contrast, the efficacy of the CFMT in classifying individuals with a face recognition deficit was confirmed. Finally, our data show that the lack of inversion effect (the difference between the total score of the upright and inverted versions of the CFMT) could be used as further index to assess congenital prosopagnosia. Overall, our results confirm the importance of having norms derived from controls with a similar experience of faces as the "potential" prosopagnosic individuals when assessing face recognition abilities.

Congenital prosopagnosia consists of the failure to develop normal face recognition ability despite intact low-level perceptual and intellectual functioning, and in the context of normal exposure to faces throughout the individual’s life. Typically, these individuals are able to perceive facial stimuli as faces but fail to identify a face as familiar or unfamiliar and to identify it. Despite the large amount of studies that have investigated face recognition in individuals with typical development and in congenital prosopagnosics over the last twenty years, we are still far from a complete understanding of the mechanisms underlying typical and atypical face recognition, and some research questions are still open. For this reason, the present dissertation investigates some perceptual effects in individuals with a selective deficit in face recognition processing in order to reach a better understanding of what happens during a successful and unsuccessful face recognition process. In particular, by using a combination of behavioural and eye-tracking methods, I investigated whether the left perceptual bias and the self-face advantage are shown by individuals with congenital prosopagnosia and are truly face-specific or not. My results demonstrate that, whereas the left perceptual bias seems to characterize the recognition of unfamiliar faces in good recognizers, individuals with congenital prosopagnosia seem to show an opposite bias (i.e., a right perceptual bias) during the recognition of the self-face. Moreover, despite their face recognition impairment, congenital prosopagnosics consistently show high accuracy in recognizing their own face (i.e., a self-face advantage). Furthermore, some of the studies I conducted on the visual scanning strategies of this population demonstrated that the self-face advantage phenomenon is not associated with a different exploration of the face stimuli, suggesting that it could reflect a more general self-advantage and not be face-specific. Finally, the evidence presented in this dissertation also highlights that individuals with face impairment from birth show some difficulties in recognizing stimuli with high degree of similarity (such as objects belonging to the same class), and that these difficulties are associated with a different pattern of visual exploration. Overall, the evidence illustrated in the present thesis helps to shed light on the mechanisms characterizing face recognition and to expand our knowledge on the impairment affecting individuals with congenital prosopagnosia.

Diagnosis of developmental or congenital prosopagnosia (CP) involves self-report of everyday face recognition difficulties, which are corroborated with poor performance on behavioural tests. This approach requires accurate self-evaluation. We examine the extent to which typical adults have insight into their face recognition abilities across four experiments involving nearly 300 participants. The experiments used five tests of face recognition ability: two that tap into the ability to learn and recognize previously unfamiliar faces [the Cambridge Face Memory Test, CFMT; Duchaine, B., & Nakayama, K. (2006). The Cambridge Face Memory Test: Results for neurologically intact individuals and an investigation of its validity using inverted face stimuli and prosopagnosic participants. Neuropsychologia, 44(4), 576–585. doi:10.1016/j.neuropsychologia.2005.07.001; and a newly devised test based on the CFMT but where the study phases involve watching short movies rather than viewing static faces—the CFMT-Films] and three that tap face matching [Benton Facial Recognition Test, BFRT; Benton, A., Sivan, A., Hamsher, K., Varney, N., & Spreen, O. (1983). Contribution to neuropsychological assessment. New York: Oxford University Press; and two recently devised sequential face matching tests]. Self-reported ability was measured with the 15-item Kennerknecht et al. questionnaire [Kennerknecht, I., Ho, N. Y., & Wong, V. C. (2008). Prevalence of hereditary prosopagnosia (HPA) in Hong Kong Chinese population. American Journal of Medical Genetics Part A, 146A(22), 2863–2870. doi:10.1002/ajmg.a.32552]; two single-item questions assessing face recognition ability; and a new 77-item meta-cognition questionnaire. Overall, we find that adults with typical face recognition abilities have only modest insight into their ability to recognize faces on behavioural tests. In a fifth experiment, we assess self-reported face recognition ability in people with CP and find that some people who expect to perform poorly on behavioural tests of face recognition do indeed perform poorly. However, it is not yet clear whether individuals within this group of poor performers have greater levels of insight (i.e., into their degree of impairment) than those with more typical levels of performance.

BackgroundDespite the well-recognised relevance of screening in colorectal cancer (CRC) control, adherence to screening is often suboptimal. Improving adherence represents an important public health strategy. We investigated the influence of family doctors (FDs) as determinant of CRC screening adherence by comparing each FDs practice participation probability to that of the residents in the same geographic areas using the whole population geocoded.MethodsWe used multilevel logistic regression model to investigate factors associated with CRC screening adherence, among 333,843 people at their first screening invitation. Standardized Adherence Rates (SAR) by age, gender, and socioeconomic status were calculated comparing FDs practices to the residents in the same geographic areas using geocoded target population.ResultsScreening adherence increased from 41.0% (95% CI, 40.8-41.2) in 2006-2008 to 44.7% (95% CI, 44.5-44.9) in 2011-2012. Males, the most deprived and foreign-born people showed low adherence. FD practices and the percentage of foreign-born people in a practice were significant clustering factors. SAR for 145 (21.4%) FDs practices differed significantly from people living in the same areas. Predicted probabilities of adherence were 31.7% and 49.0% for FDs with low and high adherence, respectively.DiscussionFDs showed a direct and independent effect to the CRC screening adherence of the people living in their practice. FDs with significantly high adherence level could be the key to adherence improvement.ImpactMost deprived individuals and foreigners represent relevant targets for interventions in public health aimed to improve CRC screening adherence.

Face-recognition deficits, referred to with the term prosopagnosia (i.e., face blindness), may manifest during development in the absence of any brain injury (from here the term congenital prosopagnosia, CP). It has been estimated that approximately 2.5% of the population is affected by face-processing deficits not depending on brain lesions, and varying a lot in severity. The genetic bases of this disorder are not known. In this study we tested for genetic association between single-nucleotide polymorphisms (SNPs) in the oxytocin receptor gene (OXTR) and CP in a restricted cohort of Italian participants. We found evidence of an association between the common genetic variants rs53576 and rs2254298 OXTR SNPs and prosopagnosia. This association was also found when including an additional group of German individuals classified as prosopagnosic in the analysis. Our preliminary data provide initial support for the involvement of genetic variants of OXTR in a relevant cognitive impairment, whose genetic bases are still largely unexplored.

Selective attention, i.e. the ability to concentrate one's limited processing resources on one aspect of the environment, is a multifaceted concept that includes different processes like spatial attention and its subcomponents of orienting and focusing. Several studies, indeed, have shown that visual tasks performance is positively influenced not only by attracting attention to the target location (orientation component), but also by the adjustment of the size of the attentional window according to task demands (focal component). Nevertheless, the relative weight of the two components in central and peripheral vision has never been studied. We conducted two experiments to explore whether different components of spatial attention have different effects in central and peripheral vision. In order to do so, participants underwent either a detection (Experiment 1) or a discrimination (Experiment 2) task where different types of cues elicited different components of spatial attention: a red dot, a small square and a big square (an optimal stimulus for the orientation component, an optimal and a sub-optimal stimulus for the focal component respectively). Response times and cue-size effects indicated a stronger effect of the small square or of the dot in different conditions, suggesting the existence of a dissociation in terms of mechanisms between the focal and the orientation components of spatial attention. Specifically, we found that the orientation component was stronger in periphery, while the focal component was noticeable only in central vision and characterized by an exogenous nature.

While the dissociation between invariant aspects of a face and emotional expressions has been studied extensively, the role of non-emotional changeable aspects in face recognition has been considered in the literature rarely. The purpose of the present study was to understand whether information on changeable aspects (with and without emotional content) can help those individuals with poor face recognition abilities (when based on invariant features) in recognizing famous faces. From a population of 80 university students we selected two groups of participants, one with poor performance (experimental group) and the other with good performance (control group). By means of a preliminary experiment, we selected videos of 16 Italian celebrities that were presented in three different conditions: motionless, with non-emotional expressions, and with emotional expressions. While the control group did not differ in the three conditions, the experimental group showed a significantly better performance in the two conditions with facial movements, which did not differ between each other. These results suggest a role of changeable aspects in the identification of famous faces, rising only in the case invariant features are not analysed properly.

The aim of the present study was to investigate the processing of the emotional and non-emotional facial expression and facial features of unfamiliar faces in individuals with Asperger's syndrome (AS) and High-Functioning Autism (HFA). To this end, we tested 14 Adults with AS and HFA and 12 typically developing individuals, matched for age and education level, in a recognition task of faces in which internal features (e.g., eyes size), emotional and non-emotional facial expressions could or could not have been manipulated. Participants were asked first to undergo the recognition task and then a change detection task of the manipulation. Results show not only a face recognition impairment (lower accuracy) in the autistic group, but also a difference in the processing of facial changeable and unchangeable features, and between emotional and non-emotional expressions.

Although omission and substitution errors in neglect dyslexia (ND) patients have always been considered as different manifestations of the same acquired reading disorder, recently, we proposed a new dual mechanism model. While omissions are related to the exploratory disorder which characterizes unilateral spatial neglect, substitutions are due to a perceptual integration mechanism. A consequence of this hypothesis is that specific training for omission-type ND patients would aim at restoring the oculo-motor scanning and should not improve reading in substitution-type ND. With this aim we administered an optokinetic stimulation to two brain-damaged patients with both unilateral spatial neglect and neglect dyslexia, MA and EP, who showed ND deficits mainly characterized by omissions and substitutions, respectively. MA also showed an impairment in oculo-motor behaviour with a non-reading task, while EP did not. The two patients presented a dissociation with respect to their sensitivity to optokinetic stimulation so that, as expected, MA was positively affected, while EP was not. Our results confirm a dissociation between the two mechanisms underlying omission and substitution reading errors in ND patients. Moreover, they suggest that such a dissociation could possibly be extendeds to the effectiveness of rehabilitative procedures, and that patients who mainly omit contralesional-sided letters would benefit from optokinetic stimulation.

21 páginas, 23 figuras, 13 tablas.-- et al., In this paper we present the Low Frequency Instrument (LFI), designed and developed as part of the Planck space mission, the ESA programme dedicated to precision imaging of the cosmic microwave background (CMB). Planck-LFI will observe the full sky in intensity and polarisation in three frequency bands centred at 30, 44 and 70 GHz, while higher frequencies (100–850 GHz) will be covered by the HFI instrument. The LFI is an array of microwave radiometers based on state-of-the-art indium phosphide cryogenic HEMT amplifiers implemented in a differential system using blackbody loads as reference signals. The front end is cooled to 20 K for optimal sensitivity and the reference loads are cooled to 4 K to minimise low-frequency noise. We provide an overview of the LFI, discuss the leading scientific requirements, and describe the design solutions adopted for the various hardware subsystems. The main drivers of the radiometric, optical, and thermal design are discussed, including the stringent requirements on sensitivity, stability, and rejection of systematic effects. Further details on the key instrument units and the results of ground calibration are provided in a set of companion papers., T.P.’s work was supported in part by the Academy of Finland grants 205800, 214598, 121703, and 121962. T.P. thanks the Waldemar von Frenckells Stiftelse, Magnus Ehrnrooth Foundation, and Väisälä Foundation for financial support. We acknowledge partial support from the NASA LTSA Grant NNG04CG90G.

14 páginas, 17 figuras, 15 tablas.-- et al., The Low Frequency Instrument (LFI) on-board the ESA Planck satellite carries eleven radiometer subsystems, called radiometer chain assemblies (RCAs), each composed of a pair of pseudo-correlation receivers. We describe the on-ground calibration campaign performed to qualify the flight model RCAs and to measure their pre-launch performances. Each RCA was calibrated in a dedicated flight-like cryogenic environment with the radiometer front-end cooled to 20 K and the back-end at 300 K, and with an external input load cooled to 4 K. A matched load simulating a blackbody at different temperatures was placed in front of the sky horn to derive basic radiometer properties such as noise temperature, gain, and noise performance, e.g. 1/f noise. The spectral response of each detector was measured as was their susceptibility to thermal variation. All eleven LFI RCAs were calibrated. Instrumental parameters measured in these tests, such as noise temperature, bandwidth, radiometer isolation, and linearity, provide essential inputs to the Planck-LFI data analysis., Planck is a project of the European Space Agency with instruments funded by ESA member states, and with special contributions from Denmark and NASA (USA). The Planck-LFI project is developed by an International Consortium lead by Italy and involving Canada, Finland, Germany, Norway, Spain, Switzerland, UK, USA. The Italian contribution to Planck is supported by the Italian Space Agency (ASI). In Finland, the Planck LFI 70 GHz work was supported by the Finnish Funding Agency for Technology and Innovation (Tekes) T.P.’s work was supported in part by the Academy of Finland grants 205800, 214598, 121703, and 121962. T.P. thank Waldemar von Frenckells stiftelse, Magnus Ehrnrooth Foundation, and Väisälä Foundation for financial support. The Spanish participation is funded by Ministerio de Ciencia e Innovacion through the projects ESP2004-07067-C03-01 and AYA2007-68058- C03-02.

24 páginas, 16 figuras, 5 tablas.-- et al., This paper provides an overview of the Low Frequency Instrument (LFI) programme within the ESA Planck mission. The LFI instrument has been developed to produce high precision maps of the microwave sky at frequencies in the range 27–77 GHz, below the peak of the cosmic microwave background (CMB) radiation spectrum. The scientific goals are described, ranging from fundamental cosmology to Galactic and extragalactic astrophysics. The instrument design and development are outlined, together with the model philosophy and testing strategy. The instrument is presented in the context of the Planck mission. The LFI approach to ground and inflight calibration is described. We also describe the LFI ground segment. We present the results of a number of tests demonstrating the capability of the LFI data processing centre (DPC) to properly reduce and analyse LFI flight data, from telemetry information to calibrated and cleaned time ordered data, sky maps at each frequency (in temperature and polarization), component emission maps (CMB and diffuse foregrounds), catalogs for various classes of sources (the Early Release Compact Source Catalogue and the Final Compact Source Catalogue). The organization of the LFI consortium is briefly presented as well as the role of the core team in data analysis and scientific exploitation. All tests carried out on the LFI flight model demonstrate the excellent performance of the instrument and its various subunits. The data analysis pipeline has been tested and its main steps verified. In the first three months after launch, the commissioning, calibration, performance, and verification phases will be completed, after which Planck will begin its operational life, in which LFI will have an integral part., The Planck-LFI project is developed by an International Consortium led by Italy and involving Canada, Finland, Germany, Norway, Spain, Switzerland, UK and USA. The Italian contribution to Planck is supported by the Agenzia Spaziale Italiana (ASI) and INAF. We also wish to thank the many people of the Herschel/Planck Project and RSSD of ESA, ASI, THALES Alenia Space Industries and the LFI Consortium that have contributed to the realization of LFI. We are grateful to our HFI colleagues for such a fruitful collaboration during so many years of common work. The German participation at the Max-Planck-Institut für Astrophysik is funded by the Bundesministerium für Wirtschaft und Technologie through the Raumfahrt- Agentur of the Deutsches Zentrum für Luft- und Raumfahrt (DLR) [FKZ: 50 OP 0901] and by the Max-Planck-Gesellschaft (MPG). The Finnish contribution is supported by the Finnish Funding Agency for Technology and Innovation (Tekes) and the Academy of Finland. The Spanish participation is funded by Ministerio de Ciencia e Innovacion through the project ESP2004-07067-C03 and AYA2007-68058-C03. The UK contribution is supported by the Science and Technology Facilities Council (STFC). C. Baccigalupi and F. Perrotta acknowledge partial support of the NASA LTSA Grant NNG04CG90G.

Planck is an ESA mission due to be launched in August 2007 with a payload of two instruments aimed at mapping the microwave sky in 9 frequency bands in the 30-850 GHz range. In this paper, after an introduction describing the basics of the Planck mission and the technical characteristics of the Low Frequency Instrument (LFI), the ground segment activities are discussed, with special emphasis on the monitoring of instrument behaviour, data processing and computational challenges, with a discussion of the foreseen solutions.