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Internal migration between Chinese provinces has increased substantially since the mid-1980s. Though it is generally agreed that this has been driven by eco nomic factors, climatic factors might also have had a part to play. The challenge is to evaluate the impact of climatic factors on migration in the simultaneous presence of changing socio-economic infuences. We resolve this challenge by carrying out a statistical multivariate regression analysis on bilateral migration rates between Chinese provinces. The analysis simultaneously includes climate change in the form of climate anomalies (temperature, precipitation, sunshine) and various socio-economic factors including energy consumption. To this end we have constructed a unique three-dimensional panel dataset (time, sending province, receiving province) with bilateral migration rates between 30 provinces for the period 1987-2015. Due to the distributional properties of the data and underlying theory we use a Poisson Pseudo Maximum Likelihood (PPML) estimator but include OLS estimates for comparison. The results suggest that increases in temperature and precipitation are signifcant migration push factors while increased sunshine discourages push migration. Provincial diferentials in per capita energy consumption and Gross Regional Product (GRP) are also signifcant drivers of migration. [ABSTRACT FROM AUTHOR]

Background In Crohn's disease ( CD) patients, stress is believed to influence symptoms generation. Stress may act via central nervous system pathways to affect visceral sensitivity and motility thus exacerbating gastrointestinal symptoms. The neural substrate underpinning these mechanisms needs to be investigated in CD. We conducted an explorative functional magnetic resonance imaging ( fMRI) study in order to investigate potential differences in the brain stress response in CD patients compared to controls. Methods 17 CD patients and 17 healthy controls underwent a fMRI scan while performing a stressful task consisting in a Stroop color-word interference task designed to induce mental stress in the fMRI environment. Key Results Compared to controls, in CD patients the stress task elicited greater blood oxygen level dependent ( BOLD) signals in the midcingulate cortex ( MCC). Conclusions & Inferences The MCC integrate 'high' emotional processes with afferent sensory information ascending from the gut. In light of these integrative functions, the stress-evoked MCC hyperactivity in CD patients might represent a plausible neural substrate for the association between stress and symptomatic disease. The MCC dysfunction might be involved in mechanisms of central disinhibition of nociceptive inputs leading to amplify the visceral sensitivity. Finally, the stress-evoked MCC hyperactivity might affect the regulation of intestinal motility resulting in exacerbation of disease symptoms and the autonomic and neuroendocrine regulation of inflammation resulting in enhanced inflammatory activity. [ABSTRACT FROM AUTHOR]

Background Crohn's disease (CD) is a chronic intestinal disorder characterized by overproduction of inflammatory cytokines and recurrent abdominal pain. Recently, brain morphological abnormalities in the pain matrix were found in patients with chronic pain disorders including irritable bowel syndrome. To investigate potential structural brain changes associated with CD, we used magnetic resonance imaging (MRI). Furthermore, we tested whether in patients gray matter (GM) volumes correlated with disease duration. Methods Eighteen CD patients in remission and 18 healthy controls underwent structural MRI. Voxel-based morphometry (VBM) is a fully automated technique allowing identification of regional differences in the amount of GM enabling an objective analysis of the whole brain between groups of subjects. VBM was used for comparisons and correlation analysis. Key Results With respect to controls, CD patients exhibited decreased GM volumes in portion of the frontal cortex and in the anterior midcingulate cortex. Disease duration was negatively correlated with GM volumes of several brain regions including neocortical and limbic areas. Conclusions & Inferences Crohn's disease is associated with brain morphological changes in cortical and subcortical structures involved in nociception, emotional, and cognitive processes. Our findings provide new insight into the brain involvement in chronic inflammatory bowel disorders. [ABSTRACT FROM AUTHOR]

Objective. To verify whether systemic biometals dysfunctions affect neurotransmission in living Alzheimer's disease (AD) patients. Methods. We performed a case-control study using magnetoencephalography to detect sensorimotor fields of AD patients, at rest and during median nerve stimulation. We analyzed position and amount of neurons synchronously activated by the stimulation in both hemispheres to investigate the capability of the primary somatosensory cortex to reorganize its circuitry disrupted by the disease. We also assessed systemic levels of copper, ceruloplasmin, non-Cp copper (i.e., copper not bound to ceruloplasmin), peroxides, transferrin, and total antioxidant capacity. Results. Patients' sensorimotor generators appeared spatially shifted, despite no change of latency and strength, while spontaneous activity sources appeared unchanged. Neuronal reorganization was greater in moderately ill patients, while delta activity increased in severe patients. Non-Cp copper was the only biological variable appearing to be associated with patient sensorimotor transmission. Conclusions. Our data strengthen the notion that non-Cp copper, not copper in general, affects neuronal activity in AD. Significance.High plasticity in the disease early stages in regions controlling more commonly used body parts strengthens the notion that physical and cognitive activities are protective factors against progression of dementia. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the reliability of somatosensory evoked potential (SEP) recordings in preterm infants to monitor the intra-uterine and extrauterine maturation of somatosensory pathways. Methods: We performed SEPs in 35 neurologically normal preterm babies (range 23–35 weeks gestational age – GA). Twenty-four of all infants were evaluated after the first 2 weeks of life, at a minimum post-menstrual age (PMA) of 31 weeks, and 31 at term corrected age. In 15 infants we obtained longitudinal recordings at both epochs. Cross-sectional and longitudinal values of first cortical potential (N1) were analyzed in relation of PMA and matched with those measured in a group of 11 fullterm babies. Results: Reproducible cortical SEPs were found in 92% of preterm babies at first recording, and in all 31 neonates at follow-up. A significant inverse correlation between the latency values of N1 and PMA at the time of first recording was observed, showing that latencies of these components rapidly decrease with increasing PMA. Regression analysis showed no significant effect on N1 latency at term correct age in dependence of GA, suggesting that extrauterine life does not affect maturation of somatosensory pathways. Interestingly, the occurrence of idiopathic respiratory distress (RDS) during clinical course after birth correlated with a delayed N1 latency at term corrected age. Conclusions: Extrauterine life does not affect maturation of somatosensory pathways in preterms without neurological deficit. Finally, the mild negative influence of RDS on maturational changes was evident. Significance: SEPs could be considered a useful tool for a non-invasive assessment of somatosensory pathways integrity in preterm infants. [Copyright &y& Elsevier]

Abstract: Objective: The increase of elderly population prompted growing research for the understanding of cerebral phenomena sustaining learning abilities, with inclusion of long-term potentiation (LTP)-like plasticity phenomena. Aim of the present study was to characterize LTP-like plasticity dependence on age and gender. Methods: A LTP-like primary motor cortex plasticity inducing a potentiation of the motor evoked potential (MEP) to focal transcranial magnetic stimulation as a consequence of a paired associative stimulation (PAS) was induced in a 50 healthy subject cohort, equally distributed for gender and age groups (25 young subjects, mean age±SD=29.8±4.5 years; elderly 61.1±4.1 years). Results: Resting motor thresholds’ excitability level increased in the elderly group, the basal MEP did not depend on gender or age. The PAS-induced primary motor cortex (M1) plastic excitability modulation was similar in young females and males, while it decreased with age in females only. Conclusions: A reduction of the PAS-induced M1 plasticity in females after menopause was documented, possibly due to an impairment of intracortical excitatory network activity. Significance: A LTP-like plasticity dependence on age was found in female only, suggesting caution in interpreting behavioural studies on learning abilities in dependence on age. [Copyright &y& Elsevier]

OBJECTIVE: Results of recent studies suggest a link between neuronal excitatory or inhibitory unbalance and depression. To investigate this relation, we studied the rest activity and the cortical excitability of the cerebral areas dedicated to hand control in 12 patients with depression. METHODS: Brain activity was recorded from the Rolandic region in both hemispheres of 12 depression patients and 11 control subjects by means of magnetoencephalography. We studied cortical excitability by focusing on the M20 and M30 components of the magnetic fields evoked by a stimulation of the median nerve. RESULTS: Parietal rest rhythms showed greater total power in patients than in control subjects. In particular, the patient's parietal alpha was higher in the right than in the left hemisphere. Primary sensory cortex excitability, expressed by the M20, appeared significantly reduced in patients with depression, but was still higher in the right than in the left hemisphere. The M30 also appeared reduced, and this reduction was significantly correlated with both depression severity and global illness. CONCLUSIONS: The patients studied were not completely drug free. For this reason, it is impossible to rule out the possibility that our results are an effect of drug assumption. Nevertheless, since all patients were well below the drugs' steady state levels when the data were recorded, the behaviour of M20 and M30 and their relation with the patients' clinical pictures suggest that an unbalance of the excitatory or inhibitory cortical activity, and especially a potentiation of the parietal afferent to the motor cortex, may be significant hallmarks of depression. [ABSTRACT FROM AUTHOR]