Effect of Plastic Deformation and H_2S on Dynamic Fracture Toughness of High Strength Casing Steel

The effects of plastic deformation and H2 S on fracture toughness of high strength casing steel（C110 steel） were investigated. The studied casing specimens are as follows： original casing, plastic deformation（PD） casing and PD casing after being immersed in NACE A solution saturated with H2S（PD＋H2S）. Instrumented impact method was employed to evaluate the impact behaviors of the specimens, meanwhile, dynamic fracture toughness（JId） was calculated by using Rice model and Schindler model. The experimental results show that dynamic fracture toughness of the casing decreases after plastic deformation. Compared with that of the original casing and PD casing, the dynamic fracture toughness decreases further when the PD casing immersed in H2 S, moreover, there are ridge-shaped feature and many secondary cracks present on the fracture surface of the specimens. Impact fracture mechanism of the casing is proposed as follows： the plastic deformation results in the increase of defect density of materials where the atomic hydrogen can accumulate in reversible or irreversible traps and even recombine to form molecular hydrogen, subsequently, the casing material toughness decreases greatly.

Observation of the effect of one-to-one education on high-risk cases of diabetic foot

BACKGROUND Diabetes is a common chronic disease,and its global incidence is on the rise.The disease is directly attributed to insufficient insulin efficacy/secretion,and patients are often accompanied by multiple complications.Diabetic foot is one of the most common complications of diabetes.Diabetic feet have ulcers and infections,which can eventually lead to amputation.Basic nursing care,such as lowering blood pressure and preventing foot skin infections in clinical nursing work,has positive significance for the prevention and control of diabetic feet.AIM To explore the positive significance of one-to-one education in high-risk cases of diabetic foot.METHODS This observation included 98 high-risk cases of diabetic foot in our hospital during the period from August 2017 to October 2019,and these patients were randomly divided into the basic nursing group and the one-to-one education group with 49 patients per group.The basic nursing group only received routine basic nursing,while the one-to-one education group gave patients one-to-one education on the basis of basic nursing.After nursing,the self-care ability and compliance behavior of the two groups were evaluated and compared between these two groups.The knowledge mastery of the patient and the satisfaction of nursing were accounted.RESULTS The assessment results of patients(self-care responsibility,self-care skills,selfconcept and self-care knowledge)were significantly higher in the one-to-one education group than in the basic nursing group.The scores of compliance behaviors(foot bathing,shoes and socks selection,sports health care)in the oneto-one education group were significantly higher than those in the basic nursing group.Patients in the one-to-one education group had a significantly higher level of knowledge mastery and satisfaction of nursing than the basic nursing group.CONCLUSION One-to-one education for high-risk cases of diabetic foot is helpful to improve the cognition and self-care ability of patients with diabetic foot,to ensure that patients follow the doctor’s advice of self-care and to improve their nursing satisfaction.

EVALUATION OF A TUBULAR MESH AND A SPIRAL STENT WOVEN FROM TITANIUM NICKEL ALLOY FOR PROSTATIC OBSTRUCTION IN PATIENTS AT HIGH RISK FOR SURGERY REPORT OF 62 CASES

The use of two urethral stents woven from titanium nickel alloy (TiNi) in the form of a tubular mesh or a spiral stent (both made in China) is described. They were implanted in 62 patients,vith prostatic outflow obstruction. till patients were considered contraindicated for surgery. They were divided into a spiral stent group (group I) treated between March 1992 and May 1993, comprising 35 cases, and a tubular mesh group (group 2) treated between October 1993 and December 1994, comprising 31 cases, including four failures in group 1. Thirty-three out of the 35 patients in group 1 were treated successfully. Good results were achieved in eight cases (22.8%) and significant improvements occurred in 24 (68.5%), giving a total effective rate of 91.3%, with a follow-up of 11 to 27 months. Fourteen stents were removed within 6 months after the insertion and six more were removed within 12 months. The mean effective time of the stent in situ was 10.8 months. All 31 cases in the mesh group were treated successfully. Dramatically good effects were obtained in 28 cases (over 90%) and distinct improvements were achieved in two, giving a total effective rate of over 96.5%, with a follow-up of 6 to 14 months (mean 10.5 months). Cystoscopy was carried out in 12 patients after 6 months following the insertion. The major part of the meshes became covered by urothelium. Compared with the spiral, the mesh makes it possible to insert a prosthesis with a larger diameter and anti-pressure. The spiral, however, can be used as a temporary alternative for the relief of prostatic obstruction. A tubular mesh can work well for the relief of prostatic obstruction and remain in situ without causing major problems for at least I year.