Hot Deformation Behavior and Microstructure Evolution of Fe-5Mn-3Al-0.1C High-Strength Lightweight Steel for Automobiles.

The hot deformation behavior of a newly designed Fe-5Mn-3Al-0.1C (wt.%) medium manganese steel was investigated using hot compression tests in the temperature range of 900 to 1150 °C, at constant strain rates of 0.1, 1, 2.5, 5, 10, and 20 s-1. A detailed analysis of the hot deformation parameters, focusing on the flow behavior, hot processing map, dynamic recrystallization (DRX) critical stress, and nucleation mechanism, was undertaken to understand the hot rolling process of the newly designed steel. The flow behavior is sensitive to deformation parameters, and the Zener-Hollomon parameter was coupled with the temperature and strain rate. Three-dimensional processing maps were developed considering the effect of strain and were used to determine safe and unsafe deformation conditions in association with the microstructural evolution. In the deformation condition, the microstructure of the steel consisted of δ-ferrite and austenite; in addition, there was a formation of DRX grains within the δ-ferrite grains and austenite grains during the hot compression test. The microstructure evolution and two types of DRX nucleation mechanisms were identified; it was observed that discontinuous dynamic recrystallization (DDRX) is the primary nucleation mechanism of austenite, while continuous dynamic recrystallization (CDRX) is the primary nucleation mechanism of δ-ferrite. The steel possesses unfavorable toughness at the deformation temperature of 900 °C, which is mainly due to the presence of coarse κ-carbides along grain boundaries, as well as the lower strengthening effect of grain boundaries. This study identified a relatively ideal hot processing region for the steel. Further exploration of hot roll tests will follow in the future.

A correlative studies between osteoporosis and blood cell composition: Implications for auxiliary diagnosis of osteoporosis.

Osteoporosis is defined as a metabolic skeletal disease characterized by a decrease of the bone mass per unit volume, caused by a variety of reasons. Increasing evidence indicate that the host inflammatory response was correlated with the occurrence and development of osteoporosis, and it has been recognized that T lymphocytes and B lymphocytes play a critical role in pathogenesis of inflammatory bone disease. Between January 2018 and December 2018, retrospective analysis of 487 patients (exclusion of patients with recent infections and hematologic disorders whose leukocyte counts or classifications are markedly abnormal) who underwent bone mineral density (BMD) examinations in Huzhou Central Hospital. The patients were divided into normal bone density group, osteopenia group, and osteoporosis group according to the T score of BMD in the left femoral neck, respectively. Statistics of the lymphocyte ratio and the monocyte ratio in the blood routine examination results during the same period were performed so as to make a comparison of the differences among the groups. The correlation of the lymphocyte ratio and monocyte ratio with the T score of BMD in the left femoral neck was also analyzed. The difference between neutrocyte ratio lymphocyte ratio and the monocyte ratio was statistically significant in both males and females among the normal bone density group, osteopenia group and osteoporosis group (P < .01 or P < .05). Inflammation plays an important role in the progression of osteoporosis. By monitoring these three indicators in blood routine examination, early intervention for osteoporosis may become possible.

Impact of interleukin-6 gene polymorphisms and its interaction with obesity on osteoporosis risk in Chinese postmenopausal women.

AIMS: To investigate the association of four single-nucleotide polymorphisms (SNPs) of the IL-6 gene with osteoporosis (OST) susceptibility. METHODS: PCR restriction fragment length polymorphism (PCR-RFLP) was carried out for SNPs detection. Generalized multifactor dimensionality reduction (GMDR) model and logistic regression model were used to examine the interaction between SNP and obesity on OST. RESULTS: Logistic regression model revealed that G allele of rs1800796 and the T allele of rs2069849 were associated with increased OST risk, compared to those with wild genotype. However, no significant correlations were found when analyzing the association of rs1800795 and rs1554606 with OST risk. GMDR analysis suggested that the interaction model composed of the rs1800796 and obesity was the best model with statistical significance (P value from sign test [Psign] = 0.012), indicating a potential gene-environment interaction between rs1800796 and obesity. Overall, the two-locus models had a cross-validation consistency of 10/10 and had the testing accuracy of 0.641. We also conducted stratified analysis for rs1800796 genotype and obesity, and found that obese subjects with CG or GG genotype have the highest OST risk, compared to subjects with CC genotype, and normal BMI OR (95% CI) = 2.21 (1.52-3.49), after adjustment for age, smoke, and alcohol consumption status. CONCLUSIONS: Our results suggested that the C allele of rs1800796 and the C allele of rs2069849 of IL-6 gene interaction between rs1800796 and abdominal obesity were all associated with increased OST risk.

Idiopathic Spinal Subdural Hematoma: Case Report and Review of the Literature.

BACKGROUND: To the best of our knowledge, there are 20 cases of idiopathic subdural hematoma (SDH), with only 1 case of idiopathic SDH located in the cervical region. We report a case of idiopathic spinal SDH and review the literature on this disease. CASE DESCRIPTION: A 43-year-old man experienced sudden onset of continuous, needle-like neck pain for 3 days with paresthesias and paraplegia. He denied any history of trauma, had no family history of bleeding diathesis, and was not on anticoagulation therapy. Hematologic investigations, liver function tests, and coagulation profile all were within reference range, and preoperative craniocerebral computed tomography was normal. Magnetic resonance imaging showed a massive compression hematoma located in the spinal canal at C2-5 level in the sagittal view and a semicircular compression hematoma in the axial view. At 1 week after C2-5 level laminectomy and evacuation of the hematoma, the patient's motor power in the left arm and left leg was improved (grades 4/5 and 5/5, respectively). CONCLUSIONS: SDH represents an emergency that could lead to significant neurologic deficit and warrants great concern. Magnetic resonance imaging is the best imaging method to diagnose this disease.

[Anterior cervical hybrid surgical treatment for multilevel cervical spondylotic myelopathy].

OBJECTIVE: To evaluate the clinical results of anterior cervical discectomy and reconstruction with a self-locking cage and internal fixation with short segmental plate for multilevel cervical spondylotic myelopathy. METHODS: From January 2012 to June 2015, a total of 106 patients received anterior cervical discectomy and reconstruction with a self-locking cage and internal fixation with short segmental plate were followed up. There were 71 males and 35 females, aged from 42 to 74 years old with an average of(55.4±5.1) years. Three segments were involved in 82 cases and four segments in 24 cases. Operation time, blood loss, postoperative drainage, and hospitalization time were recorded. Visual analogue scale(VAS) and Japanese Orthopaedic Association Score (JOA) were analyzed before and after operation(including 5 days, 3, 6, 12 months after operation and final follow-up), and the JOA improvement rate was analyzed. The cervical lordosis and ROM were measured before and after operation(including the follow-up point above) by X-rays. The postoperative complications were recorded and analyzed as well. RESULTS: All the operations were successful. The average operative time was (126.2±25.1) min, and the amount of blood loss was (82.1±26.3) ml. All the patients were followed up from 12 to 48 months with an average of (30.4±10.5) months. The VAS score of neck pain and JOA score was significantly better from 6.11±1.54 and 9.22±2.42 preoperatively to 2.14±0.51 and 12.46±1.42 at 5 days post-operation, respectively(P<0.05). The improvement rate of JOA was (56.7±21.6)%, there was no statistically significant difference of VAS, JOA scores and the improvement rate of JOA at each time after operation (P>0.05). Postoperative cervical lordosis at 3 months was significantly improved from preoperative (11.5±6.8)° to (19.6±8.9)°(P<0.05), and it can keep satisfactory stability until final follow-up(P>0.05). Postoperative ROM at 3 months was significantly decreased from the preoperative (37.6±10.4)° to (18.2±5.9)°(P<0.05), but there was no significant change in the process of follow-up (P>0.05). All the complications such as dysphagia (19 cases), axial neck pain(6 cases), cerebral fluid leakage(3 cases), and hoarseness(2 cases), got better after conservative treatment. Three cases had intervertebral space non-fusion until final follow-up(without clinical symptom), but no loosening, breakage, or displacement of internal fixation were found. CONCLUSIONS: Anterior cervical discectomy, reconstruction with a self-locking cage and internal fixation with short segmental plate which can reduce intraoperative injury, restore cervical lordosis, improve neurological function and lower postoperative complications, it is an alternative treatment for multilevel cervical spondylotic myelopathy.