High frequency limitations on mach bands

The contrast required to see Mach bands in a trapezoidal grating has been measured under different conditions. At photopic levels, increasing contrast is required as grating frequency increases. Mach bands are absent at all frequencies in scotopic viewing. Their absence at lower frequencies is not due simply to lack of suprathreshold contrast since at low frequencies contrast sensitivity is little affected by dark adaptation.Trapezoids of diminishing ramp width require increasing contrast until for a square edge a contrast of just greater than 1 would be required. This is difficult to achieve in most subjects.The Chevreul illusion behaves quite differently being unaffected by dark adaptation and grating frequency.     

Breast feeding and respiratory morbidity in infancy: a birth cohort study.

AIM: To examine the relation between the duration of breast feeding and morbidity as a result of respiratory illness and infection in the first year of life. METHODS: Prospective birth cohort study of 2602 live born children ascertained through antenatal clinics at the major tertiary obstetric hospital in Perth, Western Australia. Main outcome measures were hospital, doctor, or clinic visits, and hospital admissions for respiratory illness and infection in the first year of life. Main exposure measures were the duration of predominant breast feeding (defined as the age other milk was introduced) and partial (any) breast feeding (defined as the age breast feeding was stopped). Main confounders were gender, gestational age less than 37 weeks, smoking in pregnancy, older siblings, maternal education, and maternal age. RESULTS: Hospital, doctor, or clinic visits for four or more upper respiratory tract infections were significantly greater if predominant breast feeding was stopped before 2 months or partial breast feeding was stopped before 6 months. Predominant breast feeding for less than six months was associated with an increased risk for two or more hospital, doctor, or clinic visits and hospital admission for wheezing lower respiratory illness. Breast feeding for less than eight months was associated with a significantly increased risk for two or more hospital, doctor, or clinic visits or hospital admissions because of wheezing lower respiratory illnesses. CONCLUSIONS: Predominant breast feeding for at least six months and partial breast feeding for up to one year may reduce the prevalence and subsequent morbidity of respiratory illness and infection in infancy.     

Hepatic resections

Hepatic resection is the treatment of choice for many secondary and primary hepatic tumors. With improvement in surgical techniques and earlier recognition of hepatic tumors, there has been a renewed interest in performing hepatic resections. In this operative review, we will describe the techniques for performing right-sided and left-side hepatic resections. A major hepatic resection can be performed with less than 5% mortality and approximately a 5% to 15% morbidity. Special mention will be made of performing a hepatic resection without vascular inflow occlusion. This is necessary in performing a hepatic resection for use in live donor liver transplantation.     

For which patients with aggressive non-Hodgkin's lymphoma is prophylaxis for central nervous system disease mandatory?

Purpose: Data of a multicenter study in non-Hodgkin's lymphoma (NHL) by the Dutch Hovon Group were reanalyzed to assess the risk of relapse in the central nervous system (CNS) related to the international risk index for NHL. In addition we assessed the risk for CNS disease in relation to the presence of bone marrow localisation at presentation.Design: We focused our analysis on those patients reaching a complete remission (CR). Two hundred eighty-six patients (histological subtypes D–H Working Formulation) and with stages II–IV were analyzed. One hundred ninety-three (67%) patients reached a CR.Results: Relapse occurred in 78 patients of whom 10 patients with concomitant or isolated CNS disease. According to the international risk index the following observations were made: low risk (n = 38) nine out of 34 CR relapsed, none had CNS involvement; low-intermediate risk (n = 115) 27 out of 83 CR relapsed, three had CNS involvement; high-intermediate risk (n = 110) 37 out of 68 CR relapsed, six had CNS involvement; high risk (n = 22) four out of seven CR relapsed, one had CNS involvement. Two out of 10 developed isolated CNS disease and eight out of 10 patients developed CNS disease with systemic relapse.Conclusion: Our data show that the number of CNS relapses after CR is relatively low (10 out of 193 = 5%), with an increasing incidence in the high-risk groups according to the international risk index. The occurrence of CNS relapse seems to be related to the risk of systemic relapse after CR. No subgroup could be discriminated in which prophylactic treatment would be of substantial benefit.     

Correlation of High Seawater Temperature with Vibrio and Shewanella Infections,Denmark, 2010–2018

During 2010–2018 in Denmark, 638 patients had Vibrio infections diagnosed and 521 patients had Shewanella infections diagnosed. Most cases occurred in years with high seawater temperatures. The substantial increase in those infections, with some causing septicemia, calls for clinical awareness and mandatory notification policies.