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Ground radar interferometry technology, as a new tool for active remote sensing, has been widely used in the detection of a variety of targets, including landslides, bridges, mines, and dams. This technique usually employs a continuous observation mode with no space baseline. The detection accuracy is mainly affected by meteorological disturbances and noise in the observation environment. In a complex observation environment, meteorological disturbances can lead to phase errors of 10 mm or more, and the effects are different in the range and azimuth directions; this can seriously affect the accuracy of the measurement. In this paper, we analyze the spatial distribution of the phase of meteorological disturbances based on radar monitoring experiments in a complex environment, and propose a correction method that reduces the atmospheric disturbance phase to less than 0.6 mm and effectively improves radar observation accuracy. [ABSTRACT FROM AUTHOR]

Since 2007 the number of refugees fleeing conflict and violence has doubled to more than 25 million. We leverage high frequency data on migration, sea conditions, and riots to investigate how political and environmental risks influence migration and human smuggling across the Mediterranean Sea. We report results from two observational studies. A high frequency time-series study demonstrates that risks alter migration patterns. An event study design demonstrates the effectiveness of a policy intervention that targeted Libyan militias engaged in human smuggling. The results highlight the important role of environmental and political risks in transit countries and their implications for migration and human smuggling. [ABSTRACT FROM AUTHOR]

Prodromal Questionnaire (PQ) and Structured Interview for Prodromal Syndromes (SIPS) have been used as a two-stage process for identifying subjects at clinical high risk (CHR) of psychosis. The Prodromal Questionnaire-Brief version (PQ-B) contains 21 items derived from the PQ. The present study aimed to examine the psychometric properties of PQ-B in a Chinese help-seeking outpatient sample and to explore which items can better predict CHR diagnosis by SIPS and future transition to psychosis. In our preliminary epidemiological study, 1461 patients from a pool of 2101 individuals (15–45 years of age) completed the two-stage process. In the present study, 239 (20%) people were randomly selected among the sample who met the initial PQ-B screening criteria but had no positive diagnosis on SIPS, as well as 72 individuals with negative results on both PQ-B and SIPS, 89 prodromal and 105 psychotic subjects, yielding a total of 505 participants. The internal consistency coefficient for the PQ-B was good, with a Cronbach’s alpha of 0.897. The concordant validity of PQ-B with SIPS dichotomized diagnosis of prodrome/psychosis versus no psychosis was 0.54. To ensure 80% or a higher sensitivity and a certain specificity, 7 and 24 were respectively set as the cutoff points for the PQ-B total score and distress score for Chinese help-seeking outpatients. A logistic regression model based on six PQ-B items could allow predicting the psychotic diagnosis on SIPS, with an accuracy of 65.8%. Prodromal individuals who scored higher on the 12th item of PQ-B (Do you worry at times that something may be wrong with your mind?) were less likely to convert to psychosis. PQ-B is a useful instrument for screening CHR subjects, but the cutoff score may be higher than that recommended by the author scores for help-seeking individuals in outpatient clinics. Some specific PQ-B items may have significant predictive power on dichotomized SIPS diagnoses and deserve special attention from researchers in future studies. [ABSTRACT FROM AUTHOR]

Both schizophrenia and antipsychotic treatment are known to modulate brain morphology. However, it is difficult to establish whether observed structural brain abnormalities are due to disease or the effects of treatment. The aim of this study was to investigate the effects of illness and antipsychotic treatment on brain structures in antipsychotic-naïve first-episode schizophrenia based on a longitudinal short-term design. Twenty antipsychotic-naïve subjects with first-episode schizophrenia and twenty-four age- and sex-matched healthy controls underwent 3T MRI scans. Voxel-based morphometry (VBM) was used to examine the brain structural abnormality in patients compared to healthy controls. Nine patients were included in the follow-up examination after 8 weeks of treatment. Tensor-based morphometry (TBM) was used to identify longitudinal brain structural changes. We observed significantly reduced grey matter volume in the right superior temporal gyrus in antipsychotic-naïve patients with schizophrenia compared with healthy controls. After 8 weeks of treatment, patients showed significantly increased grey matter volume primarily in the bilateral prefrontal cortex, insula, right thalamus, left superior occipital cortex and the bilateral cerebellum. In addition, a greater enlargement of the prefrontal cortex is associated with the improvement in negative symptoms, and a more enlarged thalamus is associated with greater improvement in positive symptoms. Our results suggest the following: (1) the abnormality in the right superior temporal gyrus is present in the early stages of schizophrenia, possibly representing the core region related to schizophrenia; and (2) atypical antipsychotics could modulate brain morphology involving the thalamus, cortical grey matter and cerebellum. In addition, examination of the prefrontal cortex and thalamus might facilitate an efficient response to atypical antipsychotics in terms of symptom improvement. [ABSTRACT FROM AUTHOR]

Background: Cognitive deficits are observed throughout all developmental phases of psychosis. However, prior studies have usually focused on a limited illness period and used a wide variety of cognitive instruments. Therefore, it has been difficult to characterize or highlight cognitive functioning in different stages of psychosis. Method: We administered the RBANS (Repeatable Battery for the Assessment of Neuropsychological Status) tests to 4 participant subgroups, including healthy volunteers (controls, HC, n = 28), subjects at high risk for clinical psychosis (prodrome, CHR, n = 27), first-episode schizophrenia patients (FE-Sz, n = 26), and mid-term and long-term chronic schizophrenia patients (Ch-Sz, n =147). Comparison, correlation, and regression analyses of RBANS index scores were assessed among groups. We examined clinical outcomes over 2 years between the CHR and HC subjects, and RBANS domains were used as possible predictors for conversion to psychosis. Results: Performance on all RBANS domains was significantly impaired during a post-onset stage of psychosis (FE-Sz and Ch-Sz), and RBANS scores declined along with disease progression. Regression analyses showed that for CHR and HC subjects, baseline impairment in delayed memory (DM) significantly predicted conversion to psychosis. Additionally, partial correlations showed that for FE-Sz and Ch-Sz subjects, DM was the only correlate with a later stage of psychosis. Conclusions: Cognitive deficits broadly emerged, and diminished functioning followed along with disease progression. Impairment in DM is perhaps one domain that helps us understand the development of psychosis. A critical need is to monitor and treat memory functioning for psychotic patients throughout all phases of the disease. [ABSTRACT FROM AUTHOR]

Inhibition of return (IOR) is an attentional mechanism that previously has been reported to be either intact or blunted in subjects with schizophrenia (SCZ). In the present study, we explored the neural mechanism of IOR in SCZ by comparing the target-locked N1 and P1 activity evoked by valid-cued trials with that evoked by invalid-cued trials. Twenty-seven schizophrenia patients and nineteen healthy controls participated in a task involving covert orienting of attention with two stimulus onset asynchronies (SOAs: 700 ms and 1200 ms) during which 64-channel EEG data were recorded. Behavioral reaction times (RTs) were longer in response to valid-cued trials than to invalid-cued ones, suggesting an intact IOR in SCZ. However, reduced N1 amplitude elicited by valid-cued trials suggested a stronger inhibition of attention from being oriented to a previously cued location, and therefore a relative inhibition of perceptual processing at that location in SCZ. These results indicate that altered N1 activity is associated with the preservation of IOR in SCZ and could be a sensitive marker to track the IOR effect. [ABSTRACT FROM AUTHOR]

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition of uncontrolled immune activation leading to extreme inflammation. Primary HLH was once believed to be a disease that occurred only in infancy or young children, and was rarely diagnosed in adults. It is now understood that patients can develop primary HLH in their adolescence or adulthood. This study included 252 adolescent and adult patients with a clinical diagnosis of HLH from 35 general medical institutions across mainland China. All exons and 50 bp of flanking intronic sequence of six HLH-related genes (PRF1, UNC13D, STX11, STXBP2, SH2D1A, and BIRC4) were sequenced in these patients. We identified mutations in 18/252 (7.1%) of the patients, with changes in PRF1 being most common. Late-onset HLH often features viral infection and other predisposing factors. We conclude that late-onset primary HLH is not as rare as previously thought. Older patients should not be delayed to receive HLH-related genes testing when they are suspected with HLH. [ABSTRACT FROM AUTHOR]

Background: Abnormalities of myelin integrity have been reported in obsessive-compulsive disorder (OCD) using multi-parameter maps of diffusion tensor imaging (DTI). However, it was still unknown to what degree these abnormalities might be affected by pharmacological treatment., Objective: To investigate whether the abnormalities of white matter microstructure including myelin integrity exist in OCD and whether they are affected by medication., Methodology and Principal Findings: Parameter maps of DTI, including fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD), were acquired from 27 unmedicated OCD patients (including 13 drug-naïve individuals) and 23 healthy controls. Voxel-based analysis was then performed to detect regions with significant group difference. We compared the DTI-derived parameters of 15 patients before and after 12-week Selective Serotonin Reuptake Inhibitor (SSRI) therapies. Significant differences of DTI-derived parameters were observed between OCD and healthy groups in multiple structures, mainly within the fronto-striato-thalamo-cortical loop. An increased RD in combination with no change in AD among OCD patients was found in the left medial superior frontal gyrus, temporo-parietal lobe, occipital lobe, striatum, insula and right midbrain. There was no statistical difference in DTI-derived parameters between drug-naive and previously medicated OCD patients. After being medicated, OCD patients showed a reduction in RD of the left striatum and right midbrain, and in MD of the right midbrain., Conclusion: Our preliminary findings suggest that abnormalities of white matter microstructure, particularly in terms of myelin integrity, are primarily located within the fronto-striato-thalamo-cortical circuit of individuals with OCD. Some abnormalities may be partly reversed by SSRI treatment.

Objective: Major depressive disorder (MDD) has been characterized by abnormalities in emotional processing. However, what remains unclear is whether MDD also shows deficits in the unconscious processing of either positive or negative emotions. We conducted a psychological study in healthy and MDD subjects to investigate unconscious emotion processing and its valence-specific alterations in MDD patients., Methods: We combined a well established paradigm for unconscious visual processing, the continuous flash suppression, with positive and negative emotional valences to detect the attentional preference evoked by the invisible emotional facial expressions., Results: Healthy subjects showed an attentional bias for negative emotions in the unconscious condition while this valence bias remained absent in MDD patients. In contrast, this attentional bias diminished in the conscious condition for both healthy subjects and MDD., Conclusion: Our findings demonstrate for the first time valence-specific deficits specifically in the unconscious processing of emotions in MDD; this may have major implications for subsequent neurobiological investigations as well as for clinical diagnosis and therapy.