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  • Author: Yi Xu x
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Abstract

HNS (2, 2′, 4, 4′, 6, 6′-hexanitrostillbene) is a heat-resistant photosensitive explosive widely used in the booster charge. Investigation of the photodecomposition mechanism may provide important information for controlling and enhancing the detonation performance, also for the lifetime prediction. The UV-induced photodecomposition of HNS has been subjected to experimental studies. The UV-Vis spectra, X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance spectra (EPR) demonstrate the formation of NO2 free radicals and nitroso derivatives of HNS upon UV irradiation, which proves well known facts that C-NO2 breaking and removal of oxygen from the nitro group take part in the photodecomposition of HNS.

Abstract

Let A(p) denote the class of functions of the form f(z) = zp Σ k=1+p akzk (p ∈ N = {1, 2, 3,...}) which are analytic in the open unit disk U = {z : z ∈ C and |z| < 1} By making use of the Noor integral operator, we obtain some interesting properties of multivalent analytic functions.

Abstract

It has been suggested that the standardized growth curve (SGC) method can be used to accurately determinate equivalent dose (De) and reduce measurement time. However, different opinions regarding the applicability of the SGC method exist. In this paper, we evaluated quartz OSL SGCs of marine and coastal sediments of different grain sizes and different cores in the south Bohai Sea in China, and tested their applicability to the determination of De values. Our results suggested as follows: (1) The SGC method is applicable to both multiple- and single-aliquot regenerative-dose (MAR and SAR) protocols of OSL dating and efficiently provides reliable estimates of De. (2) Finesand quartz of different palaeodoses showed highly similar dose-response curves and an SGC was developed, but old samples using the SGC method have large uncertainties. (3) For coarse-silt quartz, two different types of dose-response curves were recorded: low-dose (≤60Gy) and high-dose (≥100Gy). The growth curves of low-dose quartz were similar to each other, facilitating the use of SGC in De estimations, but errors tended to be larger than those obtained in the SAR method. For high-dose (100–300Gy) quartz, the SGC was also found to be reliable, but there was large uncertainty in De (>300Gy) estimation. We suggest that SGC could be employed for the dating of marine and coastal sediments dating using either MAR or SAR OSL protocol and either fine-silt, coarse-silt or fine-sand quartz.

Summary

In order to investigate the main factors behind hot coal fallout during cigarette smoking, an in-use behavior survey among smokers was conducted in three locations (Guiyang, Shijiazhuang and Nanchang) in China. In addition, a measuring device was designed to record whether a flicking or tapping force was exerted to remove ash and to record the force applied as well as their characteristic parameters. We found that there was no significant difference among the behavior characteristic parameters of the users in the three locations. The proportion of consumers who applied flicking was higher than the proportion of consumers tapping. There were some differences in the in-use behavior when smoking King Size and Superslim cigarettes. The work could help to develop a suitable hot coal fallout test method.

Abstract

Stream data mining has been a hot topic for research in the data mining research area in recent years, as it has an extensive application prospect in big data ages. Research on stream data mining mainly focuses on frequent item sets mining, clustering and classification. However, traditional steam data mining methods are not effective enough for handling high dimensional data set because these methods are not fit for the characteristics of stream data. So, these traditional stream data mining methods need to be enhanced for big data applications. To resolve this issue, a hybrid framework is proposed for big steam data mining. In this framework, online and offline model are organized for different tasks, the interior of each model is rationally organized according to different mining tasks. This framework provides a new research idea and macro perspective for stream data mining under the background of big data.

Abstract

Objective To investigate the diagnostic value of brain magnetic resonance imaging in detecting central nervous system diseases among AIDS patients of different levels of T cells.

Methods Total of 164 AIDS patients who did not receive antiviral treatment were divided into 2 groups according to their baseline CD4+ T cell counts. Group A had CD4+ T cell below or equal to 50 cells/μl (n = 81) and group B had CD4+ T cells over 50 cells/μl (n = 83). All patients underwent brain MRI scan. Imaging analysis and the prevalence of the central nervous system disorders were compared between two groups.

Results Among them 48 cases were found of abnormal brain MRI, group A was higher than group B (35.8% vs. 22.9%) although without statistical significance (P = 0.065). Altogether 48 cases were diagnosed as AIDS related central nervous system disorders based on clinical symptoms, signs and laboratory findings. The prevalence of CNS disorders was higher in group A than in group B (41.9% vs. 16.8%) with statistical significance (P < 0.01).

Conclusions The patients with CD4+ T cell count less than or equal to 50 cells/μl had high prevalence of CNS diseases. Brain MRI plays an important role in the diagnosis and differentiation of CNS diseases in advanced AIDS patients. This study suggests patients with low CD4+ T cell count (≤ 50/μl) should routinely undergo MRI examination.

Abstract

Objective

The aim of this study was to explore the characteristics of and preventive management strategies for suicidal inpatients in a general hospital.

Methods

A total of 54 suicide victims were drawn from a patient safety adverse event network reporting system during hospitalization in a general hospital from November 2008 to January 2017.

Results

Subjects who committed suicide in the general hospital were women and those who suffered from malignant neoplasms during general hospital treatment. Furthermore, most of the patients who committed suicide used more violent suicide methods. The most common and lethal means was jumping from heights at the windowsill.

Conclusions

It is concluded that management strategies for suicide prevention can be provided from the aspects of patients, medical staff and the hospital environment. It is not only urgent but also feasible to reduce the suicide rate of inpatients and further improve hospital safety management.

Abstract

An efficient system for Agrobacterium tumefaciensmediated transformation of Jatropha curcas was developed in this study. Several factors affecting the transformation efficiency were optimized, including the explant type, preculture and coculture periods, usage of acetosyringone and density of A. tumefaciens. Compared with other explants, 2-day precultured and cocultured hypocotyl explants showed a significant GUS transient expression efficiency (67.7%). Moreover, adding AS showed a remarkable increase in transformation efficiency. After infecting with A. tumefaciens, hypocotyl explants were subjected to expansion and proliferation on MS medium with 1.0 mg· l-1 IBA and 0.5 mg· l-1 BA. Transformants were demonstrated by the GUS assay and PCR analysis. Rate of hypocotyl explants forming resistant calli reached 67.08%. Furthermore, in the transformed calli development, morphologic changes (calli superficial development and internal structure) were observed by SEM and LM. The present study has provided a fundamental information and research approach for the future study of inducing new traits to J. curcas and genetic modification.

Summary

Background

The chemokine C-C motif ligand 11, also known as eotaxin-1, has been identified as a novel mediator of inflammatory bone resorption. However, little is known regarding a potential role for CCL11/Eotaxin-1 in postmenopausal osteoporosis.

Objective

The scope of this study was to explore the relationship between serum CCL11/Eotaxin-1 concentrations and disease progression of postmenopausal females with osteoporosis.

Methods

A total of 83 postmenopausal women diagnosed with osteoporosis were enrolled. Meanwhile, 82 postmenopausal women with normal bone mineral density (BMD) and 85 healthy controls inner child-bearing age were enrolled as control. The Dual-energy X-ray absorptiometry was used to examine the BMDs at the femoral neck, lumbar spine 1-4 and total hip of all participants. Serum CCL11/Eotaxin-1 levels were examined by enzyme-linked immunosorbent assay. We also included inflammation marker interleukin-6 (IL-6) as well as a serum marker of bone resorption C-telopeptide cross-linked collagen type 1 (CTX-1). The Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) were recorded to evaluate the clinical severity in POMP females.

Results

Serum CCL11/Eotaxin-1 levels were significantly elevated in postmenopausal osteoporotic patients PMOP patients compared with PMNOP and healthy controls. We observed a significant negative correlation of serum CCL11/Eotaxin-1 levels with lumbar spine, femoral neck and total hip BMD. Furthermore, serum CCL11/ Eotaxin-1 concentrations were also positively related to the VAS and ODI scores. Last, serum CCL11/ Eotaxin-1 concentrations were positively associated with IL-6 and CTX-1 levels. These correlations remain significant after adjusting for age and BMI. Multivariate linear regression analysis demonstrated that CCL11/Eotaxin-1 could serve as an independent marker.

Conclusions

Serum CCL 11/Eotaxin-1 may serve as a candidate biomarker for postmenopausal osteoporosis. Therapeutics targeting CCL11/Eotaxin-1 and its related signalling way to prevent and slow progression of PMOP deserve further study.

Abstract

Objective

To evaluate the perioperative nursing of total knee arthroplasty for patients with valgus deformity of the knee.

Methods

Seventy-six patients who underwent surgical treatment were enrolled in the study from March 2014 to March 2018. The patients in the control group were treated with routine nursing. The experimental group was treated not only with routine nursing but also with health education, psychological care, family social support, and other nursing intervention. Hospital for special surgery and Pittsburgh sleep quality index were used to evaluate the effect of nursing intervention on patients after operation.

Results

All the index scores of the experimental group were lower than those of the control group (P < 0.05), indicating that the function of the diseased limb and the patient's sleep status improved significantly after the intervention.

Conclusions

Individualized nursing can improve the recovery of limb function and improve the patients’ quality of life. It is very effective for nurses to implement individualized nursing measures for patients after surgery.