General three-dimensional thermal illusion metamaterials

Thermal illusion aims to create fake thermal signals or hide the thermal target from the background thermal field to mislead infrared observers,and illusion thermotics was proposed to regulate heat flux with artificially structured metamaterials for thermal illusion.Most theoretical and experimental works on illusion thermotics focus on two-dimensional materials,while heat transfer in real three-dimensional(3D)objects remains elusive,so the general 3D illusion thermotics is urgently demanded.In this study,we propose a general method to design 3D thermal illusion metamaterials with varying illusions at different sizes and positions.To validate the generality of the 3D method for thermal illusion metamaterials,we realize thermal functionalities of thermal shifting,splitting,trapping,amplifying and compressing.In addition,we propose a special way to simplify the design method under the condition that the size of illusion target is equal to the size of original heat source.The 3D thermal illusion metamaterial paves a general way for illusion thermotics and triggers the exploration of illusion metamaterials for more functionalities and applications.

Venous thromboembolism in children with acute lymphoblastic leukemia in China:a report from the Chinese Children’s Cancer Group-ALL-2015

Venous thromboembolism(VTE)is a complication in children with acute lymphoblastic leukemia(ALL).The Chinese Children’s Cancer Group-ALL-2015 protocol was carried out in China,and epidemiology,clinical characteristics,and risk factors associated with VTE were analyzed.We collected data on VTE in a multiinstitutional clinical study of 7640 patients with ALL diagnosed in 20 hospitals from January 2015 to December 2019.First,VTE occurred in 159(2.08%)patients,including 90(56.6%)during induction therapy and 108(67.92%)in the upper extremities.T-ALL had a 1.74-fold increased risk of VTE(95%CI 1.08–2.8,P=0.022).Septicemia,as an adverse event of ALL treatment,can significantly promote the occurrence of VTE(P<0.001).Catheter-related thrombosis(CRT)accounted for 75.47%(n=120);and,symptomatic VTE,58.49%(n=93),which was more common in patients aged 12–18 years(P=0.023),non-CRT patients(P<0.001),or patients with cerebral thrombosis(P<0.001).Of the patients with VTE treated with anticoagulation therapy(n=147),4.08%(n=6)had bleeding.The VTE recurrence rate was 5.03%(n=8).Patients with VTE treated by non-ultrasoundguided venous cannulation(P=0.02),with residual thrombus(P=0.006),or with short anticoagulation period(P=0.026)had high recurrence rates.Thus,preventing repeated venous puncture and appropriately prolonged anticoagulation time can reduce the risk of VTE recurrence.