Edge-detection is all the time a major problem in the compute rearly vision, and it plays an important role in image processing. This pap er r eviews classical and new methods of edge-detection and discusses its applicati on in medical image processing.

Objective To investigate palmar hyperhidrosis (PH) and the effects on mental health in a military command.Methods 26 392 soldiers were enrolled in this study by stratified-cluster random sampling.Each was required to complete a self-administered questionnaire regarding PH.The soldiers were assessed with symptom checklist-90 (SCL-90) and the factor scores were compared with army norm and civilian norm.Results A total of 25680 subjects fulfilled the questionnaires,and the response rate was 97.3％.The prevalence of PH in the survey sample was 2.66％ and the mild,moderate,and severe PH were 1.49％,0.83％,and 0.34％,respectively.The total mean score of SCL-90 in soldiers with PH (1.72±0.54) was higher than those none PH soldiers (1.65±0.58),civilian norm (1.49±0.41) and military norm (1.63±0.30).Multiple regression analysis showed that age,level of education and severity of PH were important factors for mental health of soldiers with PH (P＜0.05).Conclusion PH is more common in the military,which affect the mental health.The health service departments should pay attention to the treatment and psychological intervention of PH.

Porcine parvovirus(PPV)is a causative agent of porcine parvovirus infection(PPI),which significantly impacts the pig industry due to its association with reproductive dysfunction.The condition is characterized by stillbirth,mummified fetuses,fetal weakness,and abortion in pregnant sows.The pathogenic mechanism remains incompletely understood,with no effective therapeutic drugs available currently.Despite extensive research on the host's response to PPV in-fection and identification of various signaling pathway transduction mechanisms,a comprehensive understanding is still lacking.This review aims to summarize the current knowledge regarding al-terations in related signaling pathways following PPV infection,provide novel insights into the pathogenesis of PPV and facilitate the drug development.

Porcine circovirus type 2(PCV2)is the main pathogen causing porcine circovirus related diseases.PCV2 infection in pigs may lead to porcine dermatitis and nephrotic syndrome(PDNS)and weaned piglets multiple system failure syndrome(PMWS),etc.At present,the pathogenic mechanism is not fully understood.PCV2 is a single strand of negative link DNA,which can cause immune suppression in the body and lead to increased secondary susceptibility,which has a syner-gistic effect with various pig diseases and brings major economic losses to the pig industry.Al-though there are commercial vaccines,the prevention of vaccines has certain limitations and there is no effective drug treatment so far,an outbreak will threaten people's life and health and public safety,resulting in significant economic losses.In order to understand the latest progress of PCV2 escape mechanism and prevention and control,this paper summarizes the inhibition of interferon production,regulation of apoptosis,regulation of autophagy,regulation of pyroptosis and inflam-matory response,evasion of adaptive immune response,and prevention and control of PCV2,in or-der to provide new theoretical ideas for the research and prevention and control of PCV2.