Biological process of soil improvement in civil engineering:A review

The concept of using biological process in soil improvement which is known as bio-mediated soil improvement technique has shown greater potential in geotechnical engineering applications in terms of performance and environmental sustainability. This paper presents a review on the soil microorganisms responsible for this process, and factors that affect their metabolic activities and geometric compatibility with the soil particle sizes. Two mechanisms of biomineralization, i.e. biologically controlled and biologically induced mineralization, were also discussed. Environmental and other factors that may be encountered in situ during microbially induced calcite precipitation （MICP） and their influences on the process were identified and presented. Improvements in the engineering properties of soil such as strength/stiffness and permeability as evaluated in some studies were explored. Potential applications of the process in geotechnical engineering and the challenges of field application of the process were identified.

Bioavailability Improvement of SLMs Based Erythromycin Ethyl Succinate using Stearic Acid-Myrj-52-based SLM＇s

Solid lipid microparticles of erythromycin ethyl succinate were prepared using solvent evaporation method to improve its bioavailability and efficacy. The solvent was allowed to evaporate after which the various entrapments were determined; the best entrapment was used in the in vivo studies to determine the bioavailability and efficacy. This study was done with albino mice. The best entrapment obtained was 83% with a loading capacity of 2.9% （Batch D） and was used in comparison with the unformulated drug to check for the in vivo efficacy. The results show higher efficacy with the formulated drug than with the pure drug both in vitro and in vivo. The in vitro test results were better despite that some enzymes which need to act on the solid lipid microparticles were not present in the in vitro assay and could lead to a reduction in the release of the drugs. In conclusion, there was improvement in efficacy, and hence bioavailability.

Beeswax-Lecithin SLMs of Erythromycin Ethyl Succinate for Treatment of Acute Bacteremia in Infected Mice

The aim of this work was to increase the efficacy of erythromycin ethyl succinate by encapsulation in beeswax lipid matrix using Myrj 52 as emulsifier. Different batches of SLM＇s （solid-lipid microparticles） were formulated and stable ones were selected. The encapsulation efficiency and loading capacities were calculated. The batch with the highest loading capacity was used for further assays. The particle size was determined by light microscopy. The sensitivity of different clinical bacterial isolates to erythromycin was tested using in vitro cultures and E. coli was selected for efficacy tests. The activity of the formulated drug was tested in the in vitro culture and compared to that of the unformulated drug. White albino mice were infected with E. coli and left for one day to develop significant bacteremia. They were then divided into 4 groups （n = 4） and treated with the formulation and unformulated drug at a dose of 7.14 mg/kg 8 hourly for 56 hours. A third group was given SLM＇s that do not contain drug, while another group was left untreated. The selected batch has an encapsulation efficiency of 94.83% with a loading capacity of 3.88%. The particle size was 17 ± 4 μm. At the end of the three day period of treatment, the group treated with unformulated erythromycin had much stooling anti weakness in the mice, and some deaths were recorded, while that treated with the formulation had 33.8% bacteremia and the clinical signs had largely subsided. The other two groups recorded deaths the following day after bacteremia induction. The results show marked improvement in efficacy of erythromycin ethyl succinate by formulation in SLMs with beeswax and lecithin as lipid matrix.

Botulinum toxin type A plus rehabilitative training for improving the motor function of the upper limbs and activities of daily life in patients with stroke and brain injury

BACKGROUND:Botulinum toxin type A(BTX-A)is mostly to be used to treat various diseases of motor disorders,whereas its effect on muscle spasm after stroke and brain injury needs further observation.OBJECTIVE:To observe the effect of BTX-A plus rehabilitative training on treating muscle spasm after stroke and brain injury.DESIGN:A randomized controlled observation.SETTINGS:Department of Rehabilitation,Department of Neurology and Department of Neurosurgery,the Second Hospital of Hebei Medical University.PARTICIPANTS:Sixty inpatients with brain injury and stroke were selected from the Department of Rehabilitation,Department of Neurology and Department of Neurosurgery,the Second Hospital of Hebei Medical University from January 2001 to August 2006.They were all confirmed by CT and MRI,and had obvious increase of spastic muscle strength in upper limbs,their Ashworth grades were grade 2 or above.The patients were randomly divided into treatment group(n=30)and control group(n=30).METHODS:①Patients in the treatment group undertook comprehensive rehabilitative trainings,and they were administrated with domestic BTX-A,which was provided by Lanzhou Institute of Biological Products,Ministry of Health(S10970037),and the muscles of flexion spasm were selected for upper limbs,20-25 IU for each site.②Patients in the treatment group were assessed before injection and at 1 and 2 weeks,1 and 3 months after injection respectively,and those in the control group were assessed at corresponding time points.The recovery of muscle spasm was assessed by modified Ashworth scale(MAS,grade 0-Ⅳ;Grade 0 for without increase of muscle strength;GradeⅣfor rigidity at passive flexion and extension);The recovery of motor function of the upper limbs was evaluated with Fugl-Meyer Assessment(FMA,total score was 226 points,including 100 for exercise,14 for balance,24 for sense,44 for joint motion,44 for pain and 66 for upper limb);The ADL were evaluated with Barthel index,the total score was 100 points,60 for mild dysfunction,60-41 for moderate dysfunction,<40 for severe dysfunction).MAIN OUTCOME MEASURES:Changes of MAS grade,FMA scores and Barthel index before and after BTX-A injection.RESULTS:All the 60 patients with brain injury and stroke were involved in the analysis of results.①FMA scores of upper limbs:The FMA score in the treatment group at 2 weeks after treatment was higher than that before treatment[(14.98±10.14),(13.10±9.28)points,P<0.05],whereas there was no significant difference at corresponding time point in the control group.The FMA scores at 1 and 3 months in the treatment group[(23.36±10.69),(35.36±11.36)points]were higher than those in the control group[(20.55±10.22),(30.33±10.96)points,P<0.01].②MAS grades of upper limbs:There were obviously fewer cases of gradeⅢin MAS at 2 weeks after treatment than before treatment in the treatment group(0,9 cases,P<0.05),whereas there was no obvious difference in the control group.There were obviously fewer cases of gradeⅢin MAS at 2 weeks and 1 month after treatment in the treatment group(0,0 case)than the control group(5,2 cases,P<0.01).③Barthel index of upper limbs:The Barthel index at 2 weeks after treatment was higher than that before treatment in the treatment group[(30.36±22.25),(28.22±26.21)points,P<0.05],whereas there was no significant difference in the control group.The Barthel indexes at 1 and 3 months after treatment in the treatment group were obviously higher than those in the control group[(20.55±10.22),(30.33±10.96)points,P<0.01].CONCLUSION:BTX-A has obvious efficacy on decreasing muscle tension after stroke and brain injury,and relieving muscle spasm;Meanwhile,the combination with rehabilitative training can effectively ameliorate the motor function of upper limbs and ADL of the patients.

HOW A WRITING ACTIVITY IMPROVED MY ENGLISH CLASS

Introduction In this article, I’d like to describe a writing activity I use to improve my students’ writing ability. The activity is a type of journal-keeping for college-English students. I ask the students to write something at regular intervals. It can be of any length. If they don’t have anything specific to write about, they can write summaries or discussions about texts from their English class. They then submit the assignment by a fixed deadline. The results have been satisfactory. Most students handed in some sort of work on time, covering a wide range of topics from personal matters (such as worries and ambitions), interests (such as hobbies, friends and hometowns) to something related to their English class (summaries, discussions or even transcriptions of model paragraphs). Stimulated by immediate feedback from the teacher, the activity has continued through the whole college-English learning period.

Improving gold recovery of Pb–Zn sulfide ore by selective activation with organic acid

Free gold and gold wrapped in sulfides are considered as the object of gold floatation. However,floatation of free gold exhibits more variables in practice.In this study, improving gold recovery of a Pb-Zn sulfide ore from Yunnan Province, China, was investigated. The results show that free gold and auriferous sulfides account for 94.99 % of total gold. Without adding organic acid in floatation, only 82 % recovery of gold could be obtained.Gold recovery in Au/Pb concentrates increases by 9.29 %with oxalate added and by 7.35 % with citric acid added,respectively, while performances of lead and arsenic nearly keep a constant. A possible reason is that free gold is of wonderful selectivity against pyrite with organic activators.A new method to enhance gold recovery is proposed.

Potential therapeutic activities and novel delivery systems of chrysin-a nature’s boon

Flavonoids are a diverse group of phytonutrients that have gained attention as dietary supplements due to their broad spectrum of therapeutic properties and negligible side effects.Chrysin,a 5,7-dihydroxyflavone,has been explored for various pharmacological effects in the last few decades.Despite vast biological activities,the use of this polyphenol seems to be compromised due to low solubility,extensive pre-systemic metabolism and thus very poor oral bioavailability.The present review elucidates various pharmacological actions of chrysin such as cardioprotective,antioxidant,neuroprotective,hepatoprotective,anti-inflammatory,anticancer and antidiabetic activities with the help of reported scientific studies.Additionally,it focuses on different formulations developed for chrysin to increase its absorption and subsequent bioavailability.This review thus analyses the beneficial effects of chrysin and gives an overview of possible techniques adopted to increase its systemic bioavailability.