Low Transmission Overhead for Polar Coding Physical-Layer Encryption

In this paper, for physical-layer security(PLS), a novel scheme of polar coding encryption is introduced in the wiretap channel(WTC) model. To decrease transmission overhead of the shared secret information and enhance the security performance against an attacker, we have employed the two following encryption technologies: Firstly, randomization of output bits is not dependent on the traditional randomized bit-channels but they are directly flipped through the random bit sequence. Secondly, for employing Advanced Encryption Standard(AES), we utilize the secret seed to extend an initial secret key of AES cryptosystem, which it appears a good avalanche performance. Result analyses demonstrate that the proposed scheme is strongly resistant against conventional attacks.

Percutaneous coronary intervention following repair of type B aortic dissection:a report of 8 cases

Objective Patients with aortic dissection have a significant incidence of coronary artery disease.The purpose of this study is to evaluate the safety and feasibility of percutaneous coronary stent in patients who have undergone endovascular stent,and to assess the effect of anti-coagulant and anti-platelet treatment on patients'thrombosis process.Methods From January 2005 to July 2007,8 patients who had undergone endovascular stent-graft during the past 1 to 7 months for type B aortic dissection repair,underwent percutaneous coronary intervention(PCI)because of coexisting coronary artery disease.Anti-coagulant and anti-platelet treatments were administrated after PCI according to the standard protocol.Patients were followed up for a mean period of 23 months.Clinical and false lumen status data were collected during the follow-up.Results PCI were technically successful in all 8 patients and no severe complications such as death,paraplegia,renal failure occurred during hospitalization.Complete false lumen thrombosis was observed in 5 patients and incomplete false lumen thrombosis in the remained 3 patients at the end of follow up.There were no major complications such as death,dissection rupture or aneurysm development occurred during the follow-up period.Conclusion Our data implied that PCI can be safely performed in patients with type B aortic dissection who have undergone endovascular stent-graft,without interrupt-ing the thrombosis process.

Ultrasound-guided fluid resuscitation versus usual care guided fluid resuscitation in patients with septic shock:a systematic review and meta-analysis

Background:Ultrasound is widely used in critical care for fluid resuscitation in critically ill patients.We conducted a systematic review to assess the relationship between ultrasound-guided fluid resuscitation strategies and usual care in septic shock.Methods:We searched PubMed,Embase,Cochrane Library,Web of Science,and registers for randomized controlled trials to evaluate the prognosis of ultrasound-guided fluid resuscitation in patients with septic shock.Results:Twelve randomized controlled studies with 947 participants were included.Ultrasound-guided fluid resuscitation in patients with septic shock was associated with reduced mortality(risk ratio:0.78;95%confidence interval[CI]:0.65 to 0.94;P=0.007)and 24-hour fluid volume(mean differences[MD]:−1.02;95%CI:−1.28 to−0.75;P<0.001),low heterogeneity(I^(2)=29%,I^(2)=0%),and increased dose of norepinephrine(MD:0.07;95%CI:0.02-0.11;P=0.002)and dobutamine dose(MD:2.2;95%CI:0.35-4.04;P=0.02),with low heterogeneity(I^(2)=45%,I^(2)=0%).There was no reduction in the risk of dobutamine use(risk ratio:1.67;95%CI:0.52 to 5.36;P=0.39;I^(2)=0%).Inferior vena cava-related measures reduced the length of hospital stay(MD:−2.91;95%CI:−5.2 to−0.62;P=0.01;low heterogeneity,I^(2)=8%)and length of intensive care unit stay(MD:−2.77;95%CI:−4.51 to−1.02;P=0.002;low heterogeneity,I^(2)=0%).The use of the passive leg-raising test combined with echocardiography to assess fluid reactivity was superior.Ultrasound-guided fluid resuscitation did not significantly change the length of the free intensive care unit stay(MD:1.5;95%CI:−3.81 to 6.81;P=0.58;I^(2)=0%).Conclusion:Ultrasound-guided fluid resuscitation in patients with septic shock is beneficial,especially when using inferior vena cava-related measures and the passive leg-raising test combined with echocardiography.

Injectable melatonin-loaded carboxymethyl chitosan(CMCS)-based hydrogel accelerates wound healing by reducing inflammation and promoting angiogenesis and collagen deposition

Carboxymethyl chitosan(CMCS)-based hydrogels have antibacterial activity,and have shown the abilities of preventing wound infection,promoting cell proliferation,accelerating collagen deposition,and stimulating hyaluronic acid formation during wound healing.As a hormone produced by the pineal gland in humans and animals,melatonin promotes skin wound healing by regulating the release of inflammatory mediators and accelerating the proliferation and migration of cells,angiogenesis,and collagen deposition.However,the combined effects of CMCS and melatonin on wound healing remain unclear.Injectable CMCS-based hydrogels containing melatonin were prepared,and their healing effects were evaluated using a full-thickness cutaneous wound model in rats.Compared with the control and the hydrogel with no melatonin groups,the melatonin-loaded hydrogel significantly increased the percentage of wound closure,promoted the proliferation of granulation tissue and re-epithelialization,and accelerated collagen deposition.Additionally,the melatonin-loaded hydrogel promoted angiogenesis and vascular endothelial growth factor receptor protein expression and increased the expression of cyclooxygenase-2 and inducible nitric oxide synthase.The melatonin-loaded hydrogel also markedly increased the expression of collagen III,α-smooth muscle actin,and transforming growth factor-β1 proteins and reduced collagen I expression.These results suggest that the melatonin-loaded hydrogel promoted granulation tissue formation and accelerated wound healing by reducing inflammation and promoting angiogenesis and collagen deposition.