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Poisoning caused by pesticides is widely recognized as a major public health problem among smallholder farmers and rural communities, including in the Caribbean. However, a lack of quality data impedes understanding of the problem and hampers the development of effective strategies for its management. To better understand the prevalence of unintentional acute pesticide poisoning (UAPP) in Trinidad and Tobago and Jamaica and the pesticides and practices involved, we conducted a cross-sectional survey of 197 and 330 vegetable farmers in Trinidad and Jamaica, respectively. The findings from this study revealed a high incidence of self-reported health effects from occupational pesticide exposure, with 48 and 16% of respondents, respectively, experiencing symptoms of UAPP within the previous 12 months. Furthermore, the substantial proportion of UAPP incidents were associated with a few highly hazardous pesticides (HHPs), particularly lambda-cyhalothrin, acetamiprid, and profenofos in Jamaica, and alpha-cypermethrin, paraquat and lambda-cyhalothrin in Trinidad. Given the well-documented adverse effects of these chemicals on human health, the results of this study should be of significant concern to health authorities in Jamaica and Trinidad. This clearly indicates an urgent need for improved regulation and safer alternatives to the use of HHPs, as well as the promotion of alternatives. We provide policy recommendations and identify alternatives to HHPs for tropical vegetable production., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Robinson, Stuart, Willis, Salmon, Ramjattan, Ganpat, Williamson, Tyrell and Saravanakumar.)

Medulloblastoma is a cerebellar grade IV tumour according to the WHO classification, mainly seen in children under the age of 15. This cancer can nevertheless occur in adults. We report the case of a 22-year-old patient with a medulloblastoma disseminated in the spine. The patient had a type 1 Arnold-Chiari malformation causing hydrocephalus treated by ventriculoperitoneal shunt. The current condition began with perineal and lower limb hypoesthesia, ataxic gait, erectile dysfunction and urinary incontinence. Subsequently, a predominant paraparesis of the right lower limb appeared. The patient was treated according to the PNET HR+5 protocol combining two courses of conventional chemotherapy followed by two courses of high-dose chemotherapy with autograft recovery. Given the excellent response, a proton therapy was then delivered to the whole cerebrospinal axis with boosts to the primary tumour sites. The case of this young adult patient shows on the one hand an atypical presentation, and on the other hand underlines, in the absence of a specific therapeutic strategy established for adults, the importance of collaboration between the adult and pediatric oncology departments, with management integrating innovations such as proton therapy and molecular typing.

Conditioned craving to trauma cues and avoidance learning have both been implicated in the high concurrence of trauma-related distress and substance misuse. Using a cue-exposure paradigm involving personalized trauma, cannabis, and neutral cues, we examined if conditioned craving and/or elevated negative affect to trauma cues are mechanisms linking PTSD and cannabis use disorder. Fifty-one trauma-exposed cannabis users were randomly presented the three cue types. Craving and emotional responses were evaluated after each cue using the Marijuana Craving Questionnaire-Short Form (Heishman et al., 2001) and the Positive and Negative Affect Schedule (Watson et al., 1988). Relief cannabis craving (compulsivity and emotionality) was significantly higher after trauma than cannabis and neutral cues (p's < 0.001) and was also higher among those with more severe PTSD symptoms (p's < 0.05). The relationship between PTSD symptom severity and cannabis craving was stronger after trauma than cannabis cues for the compulsivity component of craving (p < .05). Relief craving was also higher after the cannabis cue than after the neutral cue (expectancy and purposefulness; p < .001). Negative affect was significantly higher: after trauma than cannabis and neutral cues (p's < 0.001); and among those with more severe PTSD symptoms (p < . 005). Positive affect was significantly lower after trauma than cannabis cues (p < .05). Trauma cue exposure might promote cannabis misuse through conditioned craving as well as the desire to relieve negative affect. Conditioned cannabis craving involving an uncontrollable compulsion to use cannabis in response to trauma reminders appears particularly likely among cannabis users with more severe PTSD symptoms., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

As the prevalence of cancers increases with age, some elderly patients are confronted with multiple tumoural pathologies. The clinical case of a 70-year-old patient with adenocarcinoma of the breast and multiple myeloma complicated by severe renal failure illustrates the complexity of oncogeriatric management. The geriatric assessment makes it possible to detect frailty and provides assistance in the development of a personalized care plan while respecting the quality of life.

Purpose: Prophylaxis for febrile neutropenia (FN) is recommended for the duration of myelosuppressive chemotherapy in high-risk patients; yet, granulocyte-colony-stimulating factor (G-CSF) discontinuation occurs frequently in clinical practice. The objective of this study was to investigate the incidence of FN in real-world settings and the extent and impact of early pegfilgrastim discontinuation., Methods: This prospective, observational study enrolled patients with any-stage non-Hodgkin's lymphoma (NHL) or breast cancer initiating a new chemotherapy course with a high (> 20%) FN risk, with pegfilgrastim in cycle 1. During routine clinical visits, data were collected on FN events, discontinuation of pegfilgrastim (defined as administration of G-CSF other than pegfilgrastim for ≥ 1 cycle) and all G-CSF (and reasons), neutropenic complications and adverse drug reactions (ADRs)., Results: Overall, 943 patients were enrolled; 844 met the eligibility criteria (full analysis set) and 814 (86%) completed the study. Twenty-eight patients (3%) had 31 FN events (NHL, n = 17; breast cancer, n = 11). Twenty-six patients (3%) discontinued pegfilgrastim. Forty-four patients (5%) discontinued G-CSF. The most common reason for pegfilgrastim discontinuation was physician preference for daily G-CSF (n = 14 [2%]), and for discontinuation of all G-CSFs was reduced FN risk (n = 14 [2%]). Patients who continued G-CSF prophylaxis were less likely to experience neutropenic complications (odds ratio [95% confidence interval]: 0.26 [0.09-0.80]). Suspected ADRs to pegfilgrastim occurred in 43 patients (5%) and serious ADRs in 5 (1%)., Conclusions: FN rates were consistent with previous reports with pegfilgrastim in clinical practice. No new ADRs were observed. G-CSF discontinuation was uncommon but appeared to increase the likelihood of neutropenic complications.

Senescence is a tumor-suppressive mechanism induced by telomere shortening, oncogenes, or chemotherapy treatment. Although it is clear that this suppressive pathway leads to a permanent arrest in primary cells, this might not be the case in cancer cells that have inactivated their suppressive pathways. We have recently shown that subpopulations of cells can escape chemotherapy-mediated senescence and emerge as more transformed cells that induce tumor formation, resist anoikis, and are more invasive. In this study, we characterized this emergence and showed that senescent cells favor tumor growth and metastasis, in vitro and in vivo. Senescence escape was regulated by secreted proteins produced during emergence. Among these, we identified thrombospondin-1 (TSP1), a protein produced by senescent cells that prevented senescence escape. Using SWATH quantitative proteomic analysis, we found that TSP1 can be detected in the serum of patients suffering from triple-negative breast cancer and that its low expression was associated with treatment failure. The results also indicate that senescence escape is explained by the emergence of CD47 low cells that express a reduced level of CD47, the TSP1 receptor. The results show that CD47 expression is regulated by p21waf1. The cell cycle inhibitor was sufficient to maintain senescence since its downregulation in senescent cells increased cell emergence. This leads to the upregulation of Myc, which then binds to the CD47 promoter to repress its expression, allowing the generation of CD47 low cells that escape the suppressive arrest. Altogether, these results uncovered a new function for TSP1 and CD47 in the control of chemotherapy-mediated senescence.

Object identification is driven, in part, by the extent to which we have sensorimotor experience with the object. Importantly, the activation of embodied object representations depends on contextual information. In the present study, we use a visual masking paradigm to investigate how the availability of visual information modulates the role of manipulability in the representation of object concepts. Using both an object naming task (i.e., linguistic response) and a picture-word matching task (i.e., manual response), we provide evidence that structural manipulability (the ability to pick up an object with one hand) and functional manipulability (the action information that pertains to the ultimate use of the object) have dissociable effects on object identification. In both tasks, the effects of structural manipulability were greater when structural information was available in the image (i.e., when the objects were unmasked); in contrast, the effects of functional manipulability were greater when the objects were masked. Importantly, these effects were not due to object familiarity or the age at which the name of the objects was acquired. Our results are consistent with the activation of the two pathways within the dorsal visual stream that are part of a distributed neural network that represents embodied action information. We extend previous research by showing that visual information determines which type of embodied information drives object identification. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Background and Aims: Similar to substance addictions, reward-related cognitive motivational processes, such as selective attention and positive memory biases, have been found in disordered gambling. Despite findings that individuals with substance use problems are biased to approach substance-related cues automatically, no study has yet focused on automatic approach tendencies for motivationally salient gambling cues in problem gamblers. We tested if moderate- to high-risk gamblers show a gambling approach bias and whether this bias was related prospectively to gambling behaviour and problems., Design: Cross-sectional assessment study evaluating the concurrent and longitudinal correlates of gambling approach bias in moderate- to high-risk gamblers compared with non-problem gamblers., Setting: Online study throughout the Netherlands., Participants: Twenty-six non-treatment-seeking moderate- to high-risk gamblers and 26 non-problem gamblers community-recruited via the internet., Measurements: Two online assessment sessions 6 months apart, including self-report measures of gambling problems and behaviour (frequency, duration and expenditure) and the gambling approach avoidance task, with stimuli tailored to individual gambling habits., Findings: Relative to non-problem gamblers, moderate- to high-risk gamblers revealed a stronger approach bias towards gambling-related stimuli than neutral stimuli (P = 0.03). Gambling approach bias was correlated positively with past-month gambling expenditure at baseline (P = 0.03) and with monthly frequency of gambling at follow-up (P = 0.02). In multiple hierarchical regressions, baseline gambling approach bias predicted monthly frequency positively (P = 0.03) and total duration of gambling episodes (P = 0.01) 6 months later, but not gambling problems or expenditure., Conclusions: In the Netherlands, relative to non-problem gamblers, moderate- to high-risk gamblers appear to have a stronger tendency to approach rather than to avoid gambling-related pictures compared with neutral ones. This gambling approach bias is associated concurrently with past-month gambling expenditure and duration of gambling and has been found to predict persistence in gambling behaviour over time., (© 2017 Society for the Study of Addiction.)

Determining the speed at which a task is performed (i.e., reaction time) can be a valuable tool in both research and clinical assessments. However, standard computer hardware employed for measuring reaction times (e.g., computer monitor, keyboard, or mouse) can add nonrepresentative noise to the data, potentially compromising the accuracy of measurements and the conclusions drawn from the data. Therefore, an assessment of the accuracy and precision of measurement should be included along with the development of computerized tests and assessment batteries that rely on reaction times as the dependent variable. This manuscript outlines three methods for assessing the temporal accuracy of reaction time data (one employing external chronometry). Using example data collected from the Dalhousie Computerized Attention Battery (DalCAB) we discuss the detection, measurement, and correction of nonrepresentative noise in reaction time measurement. The details presented in this manuscript should act as a cautionary tale to any researchers or clinicians gathering reaction time data, but who have not yet considered methods for verifying the internal chronometry of the software and or hardware being used.

Houses have often been used as comparison stimuli in face-processing studies because of the many attributes they share with faces (e.g., distinct members of a basic category, consistent internal features, mono-orientation, and relative familiarity). Despite this, no large, well-controlled databases of photographs of houses that have been developed for research use currently exist. To address this gap, we photographed 100 houses and carefully edited these images. We then asked 41 undergraduate students (18 to 31 years of age) to rate each house on three dimensions: typicality, likeability, and face-likeness. The ratings had a high degree of face validity, and analyses revealed a significant positive correlation between typicality and likeability. We anticipate that this stimulus set (i.e., the DalHouses) and the associated ratings will prove useful to face-processing researchers by minimizing the effort required to acquire stimuli and allowing for easier replication and extension of studies. The photographs of all 100 houses and their ratings data can be obtained at http://dx.doi.org/10.6084/m9.figshare.1279430.

Using experimentally validated tests to measure the vigilance/alerting, orienting and executive control attention networks, we have developed a novel, theoretically driven battery for measuring attentional abilities, called the Dalhousie Computerized Attention Battery (DalCAB). The current study sought to examine the factor structure of the DalCAB as preliminary evidence for its validation as an assessment tool for the above-named attention networks. One hundred young, healthy adult participants (18 to 31 years) completed the DalCAB (simple reaction time, choice reaction time, dual task, go/no-go, visual search, vertical flanker, and item memory tasks). Exploratory factor analysis of task performance with promax rotation highlighted a 9-factor model, accounting for 54.66% of the shared variance. Factors 1, 2, and 5 are associated with measures reflecting the vigilance/alerting network (response speed, maintenance/preparation and consistency, respectively), Factor 3 is associated with the orienting network (searching measures). Factors 4, 6, 7, and 8 are associated with different aspects of the executive control network including: inhibition, working memory, filtering, and switching. The final factor is associated with vigilance/alerting (fatigue) and executive control (proactive interference). Our model provides preliminary evidence for the validation of our interpretation of the DalCAB as a measure of vigilance/alerting, orienting, and executive control attentional abilities, and contributes to the previously reported evidence for the validation of these tasks for measuring different aspects of attention. We also demonstrate the importance of each of the specific measures derived from the DalCAB tasks, and our results provide further behavioral evidence of the existence of multiple attention-related networks., ((c) 2015 APA, all rights reserved).)

Previous research has shown that photographs of manipulable objects (i.e., those that can be grasped for use with one hand) are named more quickly than non-manipulable objects when they have been matched for object familiarity and age of acquisition. The current study tested the hypothesis that the amount of visual detail present in object depictions moderates these "manipulability" effects on object naming. The same objects were presented as photographs and line-drawings during a speeded naming task. Forty-six participants named 222 objects depicted in both formats. A significant object depiction (photographs versus line drawing) by manipulability interaction confirmed our hypothesis that manipulable objects are identified more quickly when shown as photographs; whereas, non-manipulable objects are identified equally quickly when shown as photographs versus line-drawings. These results indicate that factors such as surface detail and texture moderate the role of "action" and/or "manipulability" effects during object identification tasks, and suggest that photographs of manipulable objects are associated with more embodied representations of those objects than when they are depicted as line-drawings.

There is increasing interest in the role that manipulability plays in processing objects. To date, Magnié, Besson, Poncet, and Dolisi's (2003) manipulability ratings, based on the degree to which objects can be uniquely pantomimed, have been the reference point for many studies. However, these ratings do not fully capture some relevant dimensions of manipulability, including whether an object is graspable and the extent to which functional motor associations above and beyond graspability are present. To address this, we collected ratings of these dimensions, in addition to ratings of familiarity and age of acquisition (AoA), for a set of 320 black-and-white photographs of objects. Familiarity and AoA ratings were highly correlated with previously reported ratings of the same dimensions (r = .853, p < .001, and r = .771, p < .001, respectively), validating the present norms. Grasping and functional use ratings, in contrast, were more moderately correlated with Magnié et al.'s pantomime manipulability ratings (r = .507, p < .001). These results were taken as evidence that the new manipulability ratings collected in this research capture distinct aspects of object manipulability. The complete stimuli and norms from this study may be downloaded from http://brm.psychonomic-journals.org/content/supplemental.

Centre-Surround Neural Field (CSNF) models were used to explain a possible mechanism by which information from different sources may be integrated into target likelihood maps that are then used to direct eye saccades. The CSNF model is a dynamic model in which each region in network excites near-by location and inhibits distant locations, thereby modeling competition for eye movements (saccades). The CSNF model was tested in a number of conditions analogous to a naturalistic search task in which the target was either (1) present in the expected location, (2) present in the unexpected location, or (3) absent. Simulations showed that the model predicted a pattern of accuracy results similar to those obtained by [Eckstein, M. P., Drescher, B. A., & Shimozaki, S. S. (2006). Attentional cues in real scenes, saccadic targeting, and Bayesian priors. Psychological Science, 17(11), 973-980] from human participants. However, the model predicts different saccadic latencies between conditions where Eckstein, Drescher, and Shimozaki (2006) found no significant differences. These discrepancies between model predictions and behavioural results are discussed. Additional simulations indicated that these models can also capture the qualitative flavor of eye movements in conditions with multiple targets as compared to [Findlay, J. M. (1997). Saccade target selection during visual search. Vision Research, 37(5), 617-631].

Background: Recombinant human erythropoietin (rHuEPO) therapy improves the success of autologous blood (AB) donation programs before elective surgery. The aim of this study was to evaluate iron absorption during an AB donation program with or without rHuEPO., Study Design and Methods: Thirty-two patients were randomly assigned among placebo (Group 1) or 300 (Group 2) or 600 UI per kg rHuEPO (Group 3) on the first, second, and third donation visits. All patients also received daily oral iron (200 mg Fe(+))., Results: The number of units collected in Group 3 was higher than in Group 1 (4.6 +/- 0.5 vs. 3.6 +/- 0.8 units; p < 0.01). Red blood cell (RBC) production increased in a rHuEPO dose-dependent manner. With rHuEPO, the RBC volume collected per unit presented a lower decrease with number of donated units than with placebo and was similar to that of homologous blood units. Storage iron did not influence the number of units collected, whereas circulating mobilizable iron was the limiting factor. Oral iron absorption increased in a rHuEPO dose-dependent manner (12-fold with 600 UI/kg rHuEPO) and was proportional to erythropoietic activity., Conclusion: rHuEPO does not only improve the number of AB units collected but also their quality. Storage iron cannot meet marrow iron requirements, but rHuEPO strongly increased oral iron absorption in a dose-dependent fashion through stimulation of erythropoietic activity.

Forty-six previously untreated patients with advanced breast cancer were eligible for the present randomised phase I study. It aimed to evaluate the toxicity and activity of a therapeutic sequence with epirubicin on day 1 followed by paclitaxel on day 2 (sequence A) or the reverse sequence, ie., paclitaxel on day 1 followed by epirubicin on day 2 (sequence B). The starting doses of epirubicin and paclitaxel, administered either according to sequence A or B, (level 1 cohort) were 90 mg/m2 and 175 mg/m2, respectively. Per cohort of 3 patients, the dose of paclitaxel was increased by 25 mg/m2 (levels 2 and 4) and of epirubicin by 10 mg/m2 (levels 3 and 5). Treatment was repeated with 3-week intervals. The maximal tolerated dose (MTD) was achieved at level 1 in sequence B (paclitaxel first) and level 3 (epirubicin 100 mg/m2 followed by paclitaxel 200 mg m2) in sequence A. Dose limiting toxicity (DLT) was neutropenia (+/- febrile) in both sequences. Cardiac events occurred in 28% of the patients; significant decrease in left ventricular ejection function (LVEF) was observed in 8/33 and in 2/13 patients in sequence A and B, respectively. This was associated with 5 and 1 cardiac heart failure (CHF), respectively. In 43 evaluable patients, 10 CR and 25 PR were observed (overall response rate 81%). In the 20 patients with locally advanced disease (LABC), the respective numbers were 7 CR and 11 PR; in the 23 metastatic (MBC) patients, 3 CR and 14 PR were recorded. The median survival of the both groups was not reached at 33 + months. In conclusion , the combination of epirubicin and paclitaxel has significant activity in breast cancer. The recommended sequence of both drugs in combination therapy, mainly to avoid neutropenia, is epirubicin day 1 followed by paclitaxel on day 2. Cardiac toxicity remains problematic in either sequence of administration.

Background and Objectives: It may be useful to reduce the exposure of transplant recipients to homologous blood. This may be achieved by procuring donor-derived red blood cell (RBC) units, collecting more peripheral blood progenitor cells (PBPC) with a combination of granulocyte colony-stimulating factor (G-CSF) + recombinant human erythropoietin (rHuEpo) and by administering rHuEpo post-transplantation., Design and Methods: Eight ABO-compatible donors were treated with rHuEpo and intravenous iron to collect 12 RBC units for use in their recipients. PBPC were collected after mobilization with rHuEpo and G-CSF in the same donors. The recipients received G-CSF and rHuEpo post-transplantation. A control group of 10 donor/recipient pairs received G-CSF alone for PBPC mobilization and after the transplantation., Results: Eighty-six out of 91 planned RBC units were collected in the donors without significant decrease in hematocrit because of a 4-fold increase in RBC production despite functional iron deficiency. After 2 leukaphereses, the cumulative yields of NC and CFU-GM were lower in the study group while those of BFU-E, CFU-Mix and CD34+ cells were similar. However, erythroid recovery was significantly accelerated in the study group., Interpretation and Conclusions: Collection of 12 RBC units within 6 weeks is feasible with rHuEpo and intravenous iron; this strategy allows a dramatic reduction in recipient exposure to homologous blood; rHuEpo has no synergistic effect with G-CSF for mobilization of PBPC in normal donors and may even be deleterious; and rHuEpo in the recipient may enhance erythroid engraftment.

The administration of cyclosporin A (CyA) after autologous haematopoietic stem cell transplantation (HSCT) induces a systemic autoimmune syndrome mimicking graft-vs.-host disease (GVHD). This syndrome, termed autologous GVHD has notable anti-tumour activity in animal studies. We intended to induce autologous GVHD with CyA in patients undergoing an autologous HSCT. We prospectively studied 118 patients with miscellaneous malignancies undergoing an autologous HSCT with low-dose CyA to characterize the clinical syndrome, its frequency and clinical course, and to determine the factors affecting its incidence. Patients received CyA from d -1 through to d 28, first starting at 2 mg/kg intravenously and then orally as soon as feasible. The dose was adjusted to achieve pre-dose blood levels around 100 ng/ml. A skin biopsy was performed when a skin rash was observed. Thirty-three percent of the patients developed clinical GVHD: clinical stage 1 in 21 patients, stage 2 in seven patients, and stage 3 in three patients. Although total body irradiation (TBI) or high-dose cyclophosphamide were previously thought to be needed, autologous GVHD occurred in five out of 12 patients (42%) after a preparative regimen with high-dose melphalan alone. Autologous GVHD was significantly more frequent in patients older than 33 years, in patients who had received high doses of granulocyte-macrophage colony forming units (CFU-GM) and in those with a diagnosis of myeloid malignancy, compared with those with lymphoid malignancies or solid tumours. A significant negative association was also found with HLA-DR6. In lymphoma patients, GVHD occurred more frequently in advanced disease than in first or second complete remission (CR1-2) patients. All other factors studied were not predictive for GVHD. In conclusion, CyA-induced GVHD is reproducibly and safely induced with doses of CyA adapted to achieve blood levels around 100 ng/ml. In retrospective analysis, there was no survival advantage for patients with GVHD. Phase III trials with this approach are needed to evaluate its anti-tumoral effect.

Background: Bone marrow transplantation with minor ABO incompatibility may be followed by moderate delayed hemolysis of the recipient's red cells by donor-derived ABO antibodies. This reaction may be more severe after transplantation of peripheral blood progenitor cells (PBPCs)., Case Report: A 16-year-old boy underwent an allogeneic PBPC transplant from his HLA-mismatched mother as treatment for acute myeloblastic leukemia that had proved resistant to induction chemotherapy. Transfusion of the unmanipulated PBPCs proceeded without any complication, despite the difference in ABO blood group (donor, O Rh-positive; recipient, A Rh-positive). On Day 7, a rapid drop in hemoglobin to 4 g per dL was observed, which was attributed to a massive hemolysis. All the recipient's group A red cells were destroyed within 36 hours. This delayed and rapidly progressive hemolytic anemia was not associated with the transfusion of the donor's plasma. Rather, the anti-A titer increased in parallel with marrow recovery, which suggested an active synthesis of these antibodies by immunocompetent cells from the donor against the recipient's red cells. The mother's anti-A titer was retrospectively found to be 2048. Her unusually high titer is probably due to prior sensitization during pregnancies. On Day 12, the patient developed grade IV graft-versus-host disease, which proved resistant to all treatments instituted and led to his death on Day 35., Conclusion: PBPC transplantation with minor ABO incompatibility may be associated with significant risk of massive delayed hemolysis.

Adenomatoid cystic malformations of the lung are usually diagnosed during the perinatal period. Its occurrence in adults is rare, this being the fifth case reported in literature. Improved follow-up techniques and in utero treatment have considerably improved prognosis. Differential diagnosis of pulmonary cysts should thus include this entity at all ages. Recurrent infection is usually the inaugural sign although all neighboring organs, including the heart, may be involved due to compression or extension of the inflammation. Clinical diagnosis is suggested by radiographic findings and is confirmed at pathology as surgery is generally indicated.

Between two groups of parameters (6 cutaneous and 5 bony), canonical correlations are calculated. The first only is generally retained (0.93 in men and 0.96 in women). They lead to the calculation of new parameters ("explained"), allowing to situate the subjects and to estimate theirs relationships.