bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct role of PLCβ3 in VEGF-mediated directional migration and vascular sprouting
Authors: Bhattacharya Resham , Kwon Junhye , Li Xiujuan , Wang Enfeng , Patra Sujata , Bida John Paul , Bajzer Zeljko , Claesson-Welsh Lena , Mukhopadhyay Debabrata
Published: March 2009

Endothelial cell proliferation and migration is essential to angiogenesis. Typically, proliferation and chemotaxis of endothelial cells is driven by growth factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). VEGF activates phospholipases (PLCs) – specifically PLCγ1 – that are important for tubulogenesis, differentiation and DNA synthesis. However, we show here that VEGF, specifically through VEGFR2, induces phosphorylation of two serine residues on PLCβ3, and this was confirmed in an ex vivo embryoid body model. Knockdown of PLCβ3 in HUVEC cells affects IP3 production, actin reorganization, migration and proliferation; whereas migration is inhibited, proliferation is enhanced. Our data suggest that enhanced proliferation is precipitated by an accelerated cell cycle, and decreased migration by an inability to activate CDC42. Given that PLCβ3 is typically known as an effector of heterotrimeric G-proteins, our data demonstrate a unique crosstalk between the G-protein and receptor tyrosine kinase (RTK) axes and reveal a novel molecular mechanism of VEGF signaling and, thus, angiogenesis.
An investigation into therapists' management of osteoarthritis of the carpometacarpal joint of the thumb in the UK
Authors: Davenport Barbara J
Published: March 2009

Objective

Osteoarthritis (OA) of the first carpometacarpal (CMC) joint is common and causes pain and loss of function. Conservative management is widely used to manage this condition and this study aimed to investigate the current conservative management employed by therapists in the UK.

Methods

A survey design was selected using a self-completed questionnaire as the data collection tool. The questionnaire was designed by the author and distributed to therapists by post to a range of therapy departments and to delegates attending a hand therapy course.

Results

A total of 115 out of 330 therapists (35%) responded with a completed questionnaire and the majority of the sample (97%) treated OA of the first CMC joint. Therapists used a variety of treatments for OA of the first CMC joint and the severity of the OA influenced the treatments used. Advice on activities of daily living, ergonomic advice, splints and exercise were the most commonly used treatment modalities. Therapists varied greatly in how effective they felt the different treatment modalities were in treating OA of the first CMC joint and how strong they felt the evidence base was to support their use. Most therapists used outcome measures, but many different ones were in use. Few therapists were aware of a classification system to grade the severity of OA of the first CMC joint.

Conclusions

There is a need for further research into the conservative management of this condition in order to establish the most effective treatments for each stage of the disease process.
The longitudinal validity of the quick and full version of the Disability of the Arm Shoulder and Hand questionnaire in musculoskeletal hand outpatients
Authors: Whalley Kathy , Adams Jo
Published: March 2009

Objective

Longitudinal validity refers to the ability of an outcome measure to detect clinically meaningful change in status, also referred to as responsiveness. Most recently the Department of Health has been a proponent of increased use of patient-reported outcome measures in evaluating the effectiveness of interventions to improve health. The Disability of the Arm, Shoulder and Hand (DASH) questionnaire is a comprehensive self-report measure that has been used well in rehabilitation. More recently a shortened version – the Quick DASH has been developed.

Methods

This study compared the longitudinal validity of the DASH and Quick DASH in a cohort of musculoskeletal outpatients with hand trauma and degenerative hand conditions attending an outpatient occupational therapy (OT) rehabilitation service. Responsiveness was calculated using effect sizes (ES) and standardized response mean (SRM) and paired t-tests to test for statistically significant differences.

Results

Twenty-two patients completed questionnaires. They received a mean of 12 weeks (SD = 7.5) of OT treatment. Mean baseline and discharge scores for DASH were 50.20 points (SD = 22.27) and 19.43 points (SD = 15.61), respectively and for the Quick DASH 50.43 (SD = 21.22) and 19.70 (SD = 16.01), respectively. Both the full DASH and Quick Dash yielded similar ES and SRM statistics (DASH: ES = 1.38; SRM = 1.93) (QDASH: ES = 1.51; SRM= 1.77) and t-tests showed statistically significant changes from baseline to discharge DASH ( t = 9.06; P < 0.01); Quick DASH ( t = 8.30, P < 0.01).

Conclusions

The Quick DASH and DASH demonstrated similarly high responsiveness in this patient population.
A simple effective design for a thermoplastic shoulder spica following secondary surgery for obstetrical brachial plexus palsy
Authors: Giele Henk
Published: March 2009

Secondary shoulder surgery is frequently needed to improve shoulder contracture and movement after obstetrical brachial plexus palsy. This surgery comprises subscapularis release coupled in half the cases with tendon transfers, and is generally performed from ages three to nine years. Postoperatively, a shoulder splint is used to immobilize the shoulder in a position that maintains the released position and prevents tension on the tendon transfer, if performed. A thermoplastic splint design that is light and effective is presented.
Impacts of case management for frail elderly people: A qualitative study
Authors: Sheaff Rod , Boaden Ruth , Sargent Penny , Pickard Susan , Gravelle Hugh , Parker Stuart , Roland Martin
Published: March 2009

Objective:

To assess the impacts of different forms of case management for people aged over 65 years at risk of unplanned hospital admission, in particular the impacts upon patients, carers and health service organization in English primary care; and, in these respects, compare the Evercare model with alternatives.

Methods:

Multiple qualitative case studies comparing case management in nine English Primary Care Trusts which piloted the Evercare model of case management and four sites which implemented alternative forms of case management between 2003 and 2005. Data were obtained from 231 interviews with patients, carers and other key informants, and from content analysis of documents and observation of meetings.

Results:

All the projects established functioning case management services, but none led to major service reorganization or savings elsewhere in the health care system. Many informants reported examples of admissions which case management had prevented, but overall hospital admissions did not significantly change, possibly due to increased case-finding. Patients and carers valued case management for improving access to health care, increasing psychosocial support and improving communication with health professionals.

Conclusion:

Case management was highly valued by patients and their carers, but there were few major differences in outcomes between Evercare and other models.
Tight budgetary control: A study of clinical department managers’ perceptions in Swedish hospitals
Authors: Nylinder Pia
Published: March 2009

Objective:

The composition of clinical department managers in Swedish hospitals is changing; more nondoctors and women are entering managerial positions. In parallel, most hospitals face increased pressure to contain costs. This article presents a study of managers’ perceptions of tightness of budgetary control and how their views vary systematically with personal characteristics and organizational conditions.

Method:

Data were collected through a postal survey in 2005 to 173 clinical department managers (response rate of 70%). Statistical analysis was performed by factor analysis and logistic regression.

Results:

The data suggest that clinical department managers’ perceptions of tight budgetary control were related to how long they had been in their current position, their profession (whether they were doctors or non-doctors) and their sex. Further, their perceptions could be explained by how close the managers’ departments were to their budget targets.

Conclusions:

Perception of tight budgetary control by managers depends on both their personal characteristics and the financial situation of their departments. Differences between men and women, and doctors and nondoctors call for additional research about the possible impact of changes in the composition of clinical department managers on how budgetary responsibility is exercised.
Partnerships for knowledge exchange in health services research, policy and practice
Authors: Mitchell Penelope , Pirkis Jane , Hall Jane , Haas Marion
Published: March 2009

Within the health services research community there is a growing strength of feeling that ongoing partnerships between researchers and decision-makers are critically important to effective transfer and exchange of knowledge generated from health services research. A body of literature is emerging around this idea that favours a particular model of partnership based on decision-maker involvement in research. This model is also gaining favour among health research funding bodies internationally. We argue that it is premature for the health services community to privilege any particular model of partnership between researchers and decision-makers. Rather a diversity of models should be conceptualized, explored in theory and practice, and evaluated. We identify seven dimensions that could be used to describe and differentiate models of partnerships for knowledge exchange and illustrate how these dimensions could be applied to analysing partnerships, using three case studies from recent and ongoing health services research partnerships in Australia.
Experience of continuity of care of patients with multiple long-term conditions in England
Authors: Cowie Luke , Morgan Myfanwy , White1 Patrick , Gulliford Martin
Published: March 2009

Objectives:

To examine patients’ experiences of continuity of care in the context of different long-term conditions and models of care, and to explore implications for the future organization care of long-term conditions.

Methods:

Qualitative semi-structured interviews were carried out with 33 patients recruited from seven general practices in South London. Patients were selected who had one or more of the following long-term conditions: arthritis, coronary heart disease, stroke, hypercholesterolaemia, hypertension, diabetes mellitus or chronic obstructive pulmonary disease.

Results:

Multiple morbidity was frequent and experiences of continuity were framed within patients’ wider experiences of health care rather than the context of a particular diagnosis. Positive experiences of relational continuity were strongly associated with long-term GP-led or specialist-led care. Management continuity was experienced in the context of shared care in terms of transitions between professionals or organizations. Access and flexibility issues were identified as important barriers or facilitators of continuity.

Conclusions:

Across a range of long-term conditions, patients’ experiences of health care can be understood in terms of nuanced understandings of relational and management continuity. Continuity experiences, meanings and expectations, as well as barriers and facilitators, are influenced by the model of care rather than type of condition.
The relationship between the saphenopopliteal junction and the common peroneal nerve: a cada-veric study
Authors: Balasubramaniam R , Rai R , Berridge D C , Scott D J A , Soames R W
Published: March 2009

Objectives

The variable anatomy of the short saphenous vein (SSV) and the potential failure to identify the saphenopopliteal junction (SPJ) contribute to an increased risk of damage to the common peroneal nerve (CPN) during surgical exploration. The aim of the present study was to determine the variation of the SPJ, its relationship to the CPN, and the relationship of both SPJ and CPN to defined anatomical landmarks.

Methods

Measurements of the distance between the SPJ and CPN, and the defined anatomical landmarks (fibula head, lateral joint space, lateral femoral epicondyle), were undertaken on 30 cadaveric limbs following careful dissection of the popliteal fossa.

Results

The level of SPJ termination was classified as low (below), normal (within 100 mm above) and high (more than 100 mm above), the lateral femoral epicondyle. Of the 30 limbs dissected, 70% of SPJs were normal, 23% low and 7% high. Direct measurement from the SPJ to anatomical landmarks showed a higher interquartile range (IQR) in low compared with normal terminations; however, the vertical distance from the SPJ to the fibula head showed an increase in IQR from low to normal terminations (7.1–14.2). The mean distances between the SPJ and CPN in low and normal terminations were 23.3 and 16.7 mm, respectively. Comparison of the IQR showed values very similar to low terminations having a slightly higher IQR compared with normal terminations (7.15–6.0).

Conclusion

Significant anatomic variation was observed in the termination of the SSV, with 67% located within 66 mm above the lateral femoral epicondyle. The risk of damaging the CPN during saphenopopliteal ligation may be higher for SPJs located above the lateral femoral epicondyle because of the proximity of the two structures and variability of SPJ.
Surgical treatment of severe chronic venous insufficiency caused by pulsatile varicose veins in a patient with tricuspid regurgitation
Authors: Casian D , Gutsu E , Culiuc V
Published: March 2009

A case of severe chronic venous insufficiency caused by pulsatile varicose veins in a 46-year-old man with tricuspid regurgitation is presented. Active venous leg ulcer complicated with recurrent venous bleeding and inefficacy of conservative management serve as indications for surgical treatment. This case demonstrates the possibility of radical surgical correction of pathological venous reflux by means of saphenofemoral ligation, foam sclerotherapy and subfascial endoscopic perforator surgery.
Spontaneous thoracic duct cyst presenting as a left supraclavicular mass – report of a case and review of literature
Authors: Wang Yan An , Zhang Zhi Yuan , Zheng Jia Wei , Ye Wei Min , Wang Li Zhen , Zhu Han Guang
Published: March 2009

Spontaneous and asymptomatic supraclavicular thoracic duct cysts occurring in the neck are the rarest. We report a case of a huge thoracic duct cyst occurring in the supraclavicular fossa with a review of the literature and management options. A 28-year-old female had a left supraclavicular mass with a 10-year history. A cervical thoracic duct cyst was diagnosed after chemical analysis of the milky fluid obtained by preoperative fine-needle aspiration. Treatment was achieved by surgical excision of the cyst and thoracic duct ligation. Pathological analysis of the cyst after excision confirmed the diagnosis. In the case of left supraclavicular masses, the rare differential diagnosis of thoracic duct cysts must be considered as a possibility. Magnetic resonance imaging as the imaging method of choice and chemical analysis of the milky fluid obtained by preoperative fine-needle aspiration are sufficient for primary diagnosis. The treatment of this disease consists of simple excision.
Psoas abscess due to brucellosis
Authors: Kaya Selçuk , Sayıl Özgür
Published: March 2009

Skeletal system involvement is a relatively common complication of human brucellosis. However, muscular involvement and psoas abscess are less frequently seen. Psoas abscess is usually secondary to spondylitis. We report on a 45-year-old man and a 51-year-old woman with brucellosis complicated with spondylitis and psoas abscess. The man was successfully treated with the triple antibiotic regimen with percutaneous drainage of abscess. The woman was treated using an antibiotic combination.
Iron, folate and vitamin B12 parameters in HIV-1 infected patients with anaemia in southern Brazil
Authors: Castro Luísa , Goldani Luciano Z
Published: March 2009

We conducted a study to determine the role of iron, folate and vitamin B12 in HIV-infected patients with anaemia attending a tertiary-care hospital in southern Brazil. Low serum folate levels were found in 14 (41%) HIV-infected patients; parameters of iron deficiency such as low transferring saturation index and ferritin in 10 (30%); and combined folate and iron deficiency in five (14%). Vitamin B12 deficiency was found in only two (6%) patients who presented with mean corpuscular volumes within the normal range. Our study has shown that folate and iron deficiency were frequently detected in HIV-infected patients at our institution, and should be considered in the differential diagnosis of anaemia in all HIV-infected patients independent of their HIV stage of progression.
Office haemorrhoidectomy with local anaesthesia: a feasible day-case procedure
Authors: Zafar Arshad , Ahmad Sajjad , Ansari Johar Ali
Published: March 2009

We report on 100 patients (88 men and 12 women) who underwent ligation-excision haemorrhoidectomy for prolapsing haemorrhoids in an outpatient office setting under local anaesthesia. Operating time, complications during procedure, postoperative complications and patient satisfaction with the procedure were analysed. The mean operating time was 55 (40–90) minutes. Ninety-seven were discharged three to five hours after surgery. Three patients were directly admitted to the hospital after surgery. One patient was readmitted after discharge. Severe postoperative pain occurred in eight; three suffered urinary retention; 88% were satisfied with the surgery but 12% were not. This study shows that, in selected patients, performing ligation-excision haemorrhoidectomy under local anaesthesia in the outpatient office setting is safe and viable.
Total knee replacement – the evolving sub-Saharan experience
Authors: George Akintunde Oladipo , Ofori-Atta Paul
Published: March 2009

Patients with moderate to severe osteoarthritis of the knee underwent primary elective knee arthroplasty in a well-equipped hospital in Accra, Ghana. Our main outcome measures was the new modified Oxford Knee scores (preoperative and postoperative scores). Median preoperative and postoperative knee scores were 10 and 42.5, respectively, at last follow-up with a P value <0.05 showing the reliability and significance of the scores. The average duration of inpatient hospital stay was 10 days. Of the seven patients who had surgery, one patient developed a chest infection postoperatively and another had failure of bone graft and required a revision. There was no postoperative wound infection or joint instability. The clinical outcome for this series of patients among other factors has been good within the prevailing circumstances and this shows that knee arthroplasty in developing Africa is a reality in the horizon.
Tuberculous mycotic aneurysm of aortic root: an unusual cause of cardiac tamponade
Authors: Palaniswamy Chandrasekar , Kumar Uma , Selvaraj Dhana Rekha , Pandey Bimlesh , Handa Rohini , Alappan Narendra Kumar , Sharma Hanish
Published: March 2009

We describe a young male who presented to the emergency room with sudden onset dyspnea, and was found to have aortic root aneurysm with aortic regurgitation and cardiac tamponade. He underwent a Bentall procedure, and excised aortic root tissue showed epithelioid cell granulomas with panaortitis. He was started on anti-tubercular therapy, with which he improved. Although tubercular aortitis is fairly common, tuberculous mycotic aneurysm of the aorta is rare, with involvement of the aortic root being exceedingly uncommon. We report only the fifth case in English literature of tuberculous mycotic aneurysm of the aortic root.
Peripheral neuropathy in HIV-positive patients at an antiretroviral clinic in Lilongwe, Malawi
Authors: Beadles W I , Jahn A , Weigel R , Clutterbuck D
Published: March 2009

Peripheral neuropathy (PN) is common in the setting of antiretroviral (ARV) programmes in resource-limited settings and poses significant challenges in assessment and management. A retrospective analysis was undertaken of prevalence and management of PN in a cohort of 3341 patients on highly active antiretroviral therapy. A first line ARV regimen containing stavudine (D4T) is used for clinically eligible patients. Amitriptyline is prescribed for symptom relief and in cases of persistent or escalating symptoms zidovudine (AZT) is substituted for D4T. Leg pain or numbness was reported in 1173 patients (35%). However, only 428 (13%) were given a diagnosis of PN, 228 (7%) were prescribed amitriptyline and 200 (6%) were switched to AZT. A recent pharmokinetic study in this population showed a high Cmax of D4T with the generic combination triomune (D4T 40 mg). This could account for the high prevalence of PN. The optimum time for switch to a non-D4T containing regimen is unknown.
Ascariasis-associated worm encephalopathy in a young child
Authors: Jat Kana Ram , Marwaha R K , Panigrahi Inusha , Gupta Kunal
Published: March 2009

Infestation with Ascaris lumbricoides in children has a varied manifestation, but encephalopathy is a very rare presentation. This report describes a case of ascariasis-associated encephalopathy in a child. An 18-month-old boy was admitted with altered sensorium. He had a history of vomiting and was passing Ascaris worms in the vomitus. The cerebrospinal fluid analysis did not reveal any abnormality. The patient was treated with an antihelminthic drug and he recovered completely. Worm encephalopathy should be considered as a differential diagnosis for unexplained encephalopathy in tropical areas.
Surgical training in resource-limited countries: moving from the body to the bench – experiences from the basic surgical skills workshop in Enugu, Nigeria
Authors: Ezeome E R , Ekenze S O , Ugwumba F , Nwajiobi C E , Coker O
Published: March 2009

Increasingly, many institutions and surgical groups are resorting to laboratory simulations when teaching surgical skills. The Association of Surgeons of Great Britain and Ireland partnered with the West African College of Surgeons and Johnson and Johnson Corporation to introduce basic surgical skills (BSS) training into West Africa. The local faculty at the University of Nigeria Teaching Hospital, Enugu, was able to use the opportunity of this partnership to establish a regular basic surgical skills training programme. The achievement in Enugu shows that, with a dedicated team of local faculties, giving the local medical trainers a short introduction to the practicalities of organizing and conducting BSS is enough to jump start the programme in resource-poor countries. The Enugu example is a model that should be emulated by centres in other resource-poor countries to make the course a regular feature of their surgical training.
From the Editor…
Authors: Keller L. Robin
Published: March 2009

Our first two articles in this issue focus on decision analysis in practice, from charitable decisions to government policy making. Kevin F. McCardle, Kumar Rajaram, and Christopher S. Tang present “A Decision Analysis Tool for Evaluating Fundraising Tiers.” Next, Rex V. Brown draws upon his years as a consultant in “Working with Policy Makers on Their Choices: A Decision Analyst Reminisces.” The next two articles are on aggregating probability judgments from multiple experts. Ali E. Abbas presents “A Kullback-Leibler View of Linear and Log-Linear Pools.” The final article, on “Combining the Opinions of Experts Who Partition Events Differently,” is by Robert F. Bordley. The call for papers on auctions for a special issue in memory of Michael Rothkopf is also included in this issue.
Tangential visibility: Becoming self through creating socio-cultural portraits
Authors: Grushka Kathryn
Published: March 2009

This paper reports on student learning outcomes of a Visual Art curriculum in a secondary school context in New South Wales. The case study presented was informed by longitudinal research carried out between 19992001. The research established that students continue to be preoccupied with the question Who am I? as it informs their humanity and subjectivity. However, a significant number elected to deepen understanding of self through studying the narratives of others. The research also identified a shift away from traditional self-portraits to socio-cultural narrative portraits. Tangential visibility was defined as the ability to find new, creative insights about self at intersections between self and other. This orientation offers students opportunities to relocate their voices in representing others. From this position they can explore spaces between individual and collective subjectivities and relocate their identities in a wider, socio-cultural performative narrative.
Rapid Estimation of Compaction Parameters for Field Control
Authors: Nagaraj TS , Lutenegger AJ , Pandian NS , Manoj M
Published: March 2009

Compaction as a practical means of achieving the desired strength, compressibility, and permeability characteristics of fine-grained soils has been appreciated since the time early earth structures were built. In this paper, simple phenomenological relationships are proposed for estimating compaction characteristics, based on the analysis of compaction curves of fine-grained soils for different compactive efforts. A simple stepwise procedure is presented for adoption, the validity of which has been demonstrated from laboratory test data for this purpose.
Image Processing Technique for Determining the Concentration of a Chemical in a Fluid-Saturated Porous Medium
Authors: Dong W , Selvadurai APS
Published: March 2009

This paper presents a color visualization-based image processing technique for the quantitative determination of a chemical dye concentration in a fluid-saturated porous column composed of glass beads. In this image processing technique, an image filter is designed by taking into account the porous structure of the medium and color characteristics of both the fluid and the solid particles to extract the color representation of the dye solution in pore space, which enables the image quantification. A comparison of experimental results with analytical and numerical simulations illustrates the efficiency and accuracy of the image processing method for determining the chemical concentrations in the porous medium.
Measurement of Rock Joint Roughness by 3D Scanner
Authors: Hong E-S , Lee I-M , Lee J-S
Published: March 2009

Many methods have been used to measure rock joint surface roughness more accurately. However, true roughness has been distorted and underestimated by differences in the sampling interval of the measurement methods. Thus, current measurement methods produce a dead zone and distorted roughness profiles. This study proposes a new rock joint surface roughness measurement method by use of a camera-type three-dimensional (3D) scanner as an alternative to current methods. For this study, the underestimation of artificial roughness is analyzed by using the current measurement method of laser profilometry. We then replicate eight specimens from two rock joint surfaces, and digitize them by 3D scanners. Finally, the roughness coefficient values obtained from eight numbers of the 3D surface data sets and from 320 numbers of two-dimensional profiles data sets are analyzed by using the current measurement methods and our proposed measurement method. The artificial simulation confirms that the sampling interval is one of main factors for the distortion of roughness and shows that current methods may not consider the inclination of waviness. The experimental results showed that the camera-type 3D scanner produced 10 % larger roughness values than those of the current methods. The proposed new method is a faster, more precise and more accurate method than the current methods for the measurement of rock joint roughness, so that it can be promising technique in this area of study.
Centrifuge Testing of Offshore Filters
Authors: Gaudin C , Watson PG , Randolph MR
Published: March 2009

This paper presents original centrifuge tests performed to study the interaction between clay soils and various filter types proposed for use in the under-base pumping system on the Yolla A Platform foundations. The experimental device described allows a “suction” to be applied behind the face of the filter, and to study potential for (a) penetration of clay through the filter, and (b) blockage of the filter. Results have shown that tapered wire mesh filters may (at least partially) block during penetration into the clay, but that these could be unblocked by application of moderate pressures inside the filter.
A Device to Cyclic Lateral Loaded Model Piles
Authors: Peng JR , Clarke BG , Rouainia M
Published: March 2009

Model tests on small scale piles subject to cyclic lateral loading have been carried out with the purpose of simulating the pile soil behavior and its lateral resistance under environmental loads. An efficient mechanical loading system has been developed. This system is able to provide both one-way and two-way cyclic lateral loads. Frequencies and load levels in both directions can be varied in order to simulate different load conditions. There is no limitation on the number of cycles. A series of lateral cyclic loading tests for a monopile in dry sand have been carried out to demonstrate the efficiency and effectiveness of this loading system. The benefits of this innovative loading system are presented.
A Micropenetrometer for Detecting Structural Strength Inside Soft Soils
Authors: Liu Z , Shi B , Sheng D
Published: March 2009

A micropenetrometer is developed to measure structural strength inside soft soils. Different from the traditional detective technology for soil structure, the micropenetrometer is an intrusion technology to estimate the characteristics of soft soils. The work principle and main configuration of the micropenetrometer are introduced, followed by its calibration and some operation techniques. Finally, two application tests are carried out. Different soil textures such as sandy soil or clayey soil have different types of penetration curves. Through the end resistance variation, detailed description of the structural strength along penetration depth can be obtained. In addition, three-dimensional strength distribution on the vertical or transverse sections can be achieved from the penetration data evenly arranged on the grid nodes of the same surface through interpolation method. Such a technique is of significance for checking the effectiveness of soil improvement or monitoring the moisture movement in soil.
Physical and Mechanical Properties of Injected Sand with Latex—Superplasticized Grouts
Authors: Anagnostopoulos CA
Published: March 2009

Grouting is the most common technical method with many applications; e.g., it is used for soil stabilization and strengthening, for reduction of water ingress to underground facilities or of water loss through a dam foundation, etc. Grouts comprise several constituents, that are combined in many ways depending on the in situ conditions and the outcome desired each time. Superplasticizers, accelerators, antifreezers, airentraining agents and many others are generally used to improve the quality of cement grouts and, consequently, their effectiveness on strength (especially bond strength), durability, impermeability, and resistance to chemical erosion of the grouted soil or rock mass.

A comprehensive laboratory work was carried out in order to study the rheological properties of acrylic resin (latex)—superplasticized grouts and their influence, when injected, on the physical (water permeability, porosity) and mechanical characteristics (compressive strength, elastic modulus, durability) of a granular soil.
Specimen Size and Scale Effects of Direct Shear Box Tests of Sands
Authors: Cerato AB , Lutenegger AJ
Published: March 2009

The direct shear test has survived over the past 50 years in geotechnical engineering applications because of its simplicity and repeatability. Many laboratories perform direct shear box tests on sands to determine the friction angle φ′, or shear strength of the sand for engineering design purposes. However, there are different size shear boxes in use today and the effect of the varying specimen size on the resulting friction angle used in foundation deign has never before been investigated thoroughly. Five sands with different properties were tested in three square shear boxes of varying sizes (60 mm, 101.6 mm, and 304.8 mm), each at three relative densities (dense, medium, and loose). Results of the direct shear tests show that the friction angle φ′ can be dependent on specimen size and that the influence of specimen size is also a function of sand type and relative density. The tests indicate that for well-graded, angular sands, φ′ decreases as box size increases and that the influence of box size is dependent on relative density. The paper provides a description of the test methods and presents the test results.
Analysis of Installation of FDR Sensors in a Hard Soil
Authors: Navarro V , Candel M , Yustres A , Merlo O , Mena M
Published: March 2009

Success using capacitance sensors is critically dependent upon the proper installation of access tubes to maximize soil contact. In this paper we present the technique followed in the installation of 11 access tubes in a hard soil from Alcazar de San Juan (central Spain) to optimize this contact.
Investigations on Sand Reinforced with Different Geosynthetics
Authors: Latha MG , Murthy VS
Published: March 2009

This paper presents results of triaxial compression tests on sand reinforced with different types of geosynthetics in different layer configurations to study the effect of quantity of reinforcement and tensile strength of the geosynthetic material on the mechanical behavior of geosynthetic-reinforced sand. The reinforcement types used are woven geotextile, geogrid, and polyester film. The layer configurations used are two, three, four, and eight horizontal reinforcing layers in a triaxial test sample. From the triaxial tests, it is found that the geosynthetic reinforcement imparts cohesive strength to otherwise cohesionless sand. The effect of reinforcement on the friction angle was found to be insignificant. The magnitude of imparted apparent cohesion is found to depend not only on the tensile strength of the geosynthetic material but also the surface roughness changes during loading. Special triaxial tests using rice flour as the reinforced medium, microscopic images, and surface roughness studies revealed the effect of indent formation on the surface of polyester film, which was the reason for the unusually high strength exhibited by the sand reinforced with polyester film.
Digitally Controlled Simple Shear Apparatus for Dynamic Soil Testing
Authors: Duku P. M. , Stewart J. P. , Whang D. H. , Venugopal R.
Published: March 2009

We describe the characteristics of a simple shear apparatus capable of applying realistic multidirectional earthquake loading to soil specimens. This device, herein termed the Digitally Controlled Simple Shear (DC-SS) apparatus, incorporates features such as servohydraulic actuation and true digital control to overcome control limitations of some previous dynamic soil testing machines. The device is shown to be capable of reproducing sinusoidal and broadband command signals across a wide range of frequencies and amplitudes, although the device has limited control capabilities for very small command displacements (less than approximately 0.005 mm). The small deformation limitation results from noise introduced to the control system from analog-to-digital conversion of feedback signals. We demonstrate that bidirectional command signals can be accurately imparted with minimal cross coupling, which results from an innovative multiple-input, multiple-output digital control system. The capabilities of the device are demonstrated with a series of broadband tests on unsaturated soil specimens subjected to uni- and bidirectional excitation.
A Novel Trimming Technique for Frozen Sand Specimens
Authors: Sanzeni Alex , Germaine John T. , Whittle Andrew J. , Colleselli Francesco
Published: March 2009

A trimming technique is described for the preparation of specimens of frozen sand for one-dimensional thawing and consolidation tests. Specimens are trimmed directly into the apparatus’ confining ring using its cylindrical cutting edge; a heated metal blade is employed to remove the excess soil, while dry ice is used as coolant. The technique is performed at room temperature and is particularly suitable for 1-D thaw-consolidation tests where dimensional tolerances are critical. The technique was applied for preparing specimens of frozen sand from the Venice Lagoon deposits for 1-D compression tests in the Constant Rate of Strain (CRS) apparatus (Wissa et al. 1971). Specimen handling and test setup are described in detail; testing procedure included measurement of axial strain during thawing.
Probabilistic CPT Method for Estimating the Ultimate Capacity of Friction Piles
Authors: Abu-Farsakh Murad Y. , Titi Hani H.
Published: March 2009

This paper presents a probabilistic CPT method to estimate the ultimate capacity of driven friction piles utilizing CPT data. A database of 35 square PPC piles that were loaded to failure and their adjacent CPT were used to develop this method. Backcalculation was carried out to calibrate the correlation factors needed to determine the unit end bearing (qb) and unit skin friction (f) of the pile from CPT data (qc, fs) based on the probability of having each soil type. The ultimate pile capacities (QP) of the investigated piles estimated by the proposed method, three other CPT methods, and static α and β methods were compared with the measured pile capacities obtained from pile load tests. Statistical analyses were carried out to evaluate the reliability of the probabilistic CPT method and the results showed that the proposed method can predict the ultimate capacity of the piles with good accuracy. The capability of the proposed method was further verified by predicting the capacities of an additional 17 pile load tests. The probabilistic CPT method, in addition to Schmertmann, α, and β methods were calibrated to evaluate the resistance factors needed for the design of single driven piles based on the LRFD method.
A New Isotropic Cell for Studying the Thermo-Mechanical Behavior of Unsaturated Expansive Clays
Authors: Tang Anh-Minh , Cui Yu-Jun , Barnel Nathalie
Published: March 2009

This paper presents a new suction-temperature controlled isotropic cell that can be used to study the thermo-mechanical behavior of unsaturated expansive clays. The vapor equilibrium technique is used to control the soil suction; the temperature of the cell is controlled using a thermostat bath. The isotropic pressure is applied using a volume/pressure controller that is also used to monitor the volume change of soil specimen. Preliminary experimental results showed good performance of the cell.
A Laboratory Model to Study Arching within a Hydraulic Fill Stope
Authors: Pirapakaran Kandiah , Sivakugan Nagaratnam
Published: March 2009

A simple laboratory apparatus, to study the effects of arching within a hydraulic fill mine stope, was developed. Four different model stopes, two circular and two square, made from Perspex, were used in the study. A dry hydraulic fill obtained from a local mine was used in the study. The model was filled in 100-mm layers, and the fractions of the fill weight, carried by the bottom and the wall of the stope, were separately measured. From these measurements, the variation of average vertical stress with depth could be computed. These experimental values were compared against those obtained from numerical modeling using FLAC and FLAC3D, and the agreement was excellent, thus validating the numerical model.
Centrifuge Modeling of Surface Blast Effects on Underground Structures
Authors: De Anirban , Zimmie Thomas F.
Published: March 2009

The effects of surface blasts on underground structures were studied through centrifuge model tests. Centrifuge scaling relationships make it possible to model the effects of large explosions, using a relatively small quantity of explosives under a high g-level. Centrifuge tests, conducted at 70 g, using 2.6 mg of TNT equivalent of explosives, resulted in explosions equivalent to those using 8.7 kN (0.9 tons) of TNT equivalent under normal (1 g) gravity. Strains induced at different locations of the model structure due to the explosion were measured using strain gages. Results indicated that the strains depend on the thickness and nature of the intervening medium. The presence of a polyurethane geofoam compressible inclusion barrier appeared to mitigate the impact of the explosion. Centrifuge model testing is useful in determining the effectiveness of different design alternatives, in studying the mitigating effects of different barrier systems, and in verifying and calibrating results of numerical models related to explosions and underground structures.
An Alternative Test Method for Assessing Consistency Limits
Authors: Lee Landris T. , Freeman Reed B.
Published: March 2009

Experiments were conducted to assess simpler alternatives for estimating the Atterberg (liquid and plastic) limits as needed during military field reconnaissance and combat engineering exercises. Eight non-ASTM test methods were compared to the Casagrande cup liquid limit method and ten non-ASTM alternatives were compared to the rolled-bead plastic limit method for three cohesive soils having wide plasticity index ranges. Only one non-ASTM method yielded results within 10 % of the ASTM liquid and plastic limit values. This unique test method was created from a unified (dual-weight) fall cone apparatus and procedure to enable simple assessment of soil consistency limits.
A Numerical View into Direct Shear Specimen Size Effects
Authors: Jacobson Douglas E. , Valdes Julio R. , Evans T. Matthew
Published: March 2009

The ASTM D 3080-04 standard, Standard Test Method for Direct Shear Test of Soils under Consolidated Drained Conditions, indicates that the direct shear test specimen width L must be at least ten times larger than the largest particle in the specimen, L/d ≥ 10. The results documented in this note provide visual insight into specimen size and boundary effects through discrete element simulations conducted with numerical specimens ranging in size from L/d = 6.5 to L/d = 177. Particle translation data indicate that in the tested configuration, localized shear zones located far from the specimen boundaries develop only when the specimen size is L/d > 58. The results provide a description of the microstructure evolution during shearing and suggest that the ASTM specimen size criterion may be inappropriate when localized shear banding in uniform granular materials is sought.
Uplift Behavior of Horizontal Anchor Plates Buried in Geosynthetic Reinforced Slopes
Authors: El Sawwaf Mostafa A.
Published: March 2009

Uplift behavior of horizontal anchor plates located near sandy earth slopes with and without geosynthetic reinforcement has been investigated in model tests. Several configurations of reinforcement layers were used to reinforce the sandy soil over anchor plates. Many factors, such as relative density of sand, embedment depths, and the location of the plate relative to the slope crest, along with geosynthetic parameters including size, type, number of layers, and the proximity of the layer to the plate have been studied in a scale model. The failure mechanism and the associated rupture surface were observed and discussed. Test results showed that using geosynthetic reinforcement has a significant effect in improving the uplift capacity of the anchorage plate. However, it was found that inclusion of one layer that is placed resting directly on top of the anchor plate was more effective in enhancing the anchor capacity than reinforcing the slope itself. Based on test results, critical values were discussed and recommended, but should be validated in full-scale or centrifugal model tests.
An Empirical Relationship between Rock Structure Rating and Rock Mass Rating
Authors: Sarsby RW , Rama Sarma K
Published: March 2009

Prediction of support pressures for underground openings is one of the most difficult tasks in rock engineering. The difficulties associated with the selection of reliable material properties, laws of material behavior, stress environment, etc. (which are essential for satisfactory application of analytical methods and numerical techniques) and the simplicity of the classification systems have collectively contributed to the popularity of empirical approaches for support design. The unpredictable nature of weathering enhances the complexity of the assessment of rock masses. In this study an attempt has been made to derive a simple relationship between rock structure rating and rock mass rating, which will permit accurate estimation of engineering properties of rock using easily measured parameters. The data used to formulate the empirical relationships came from tests conducted on rock samples collected from 45 boreholes at various locations between Visakhapatnam and Koraput (India).
Centrifuge Modeling of Solid Waste Landfill Systems—Part 1: Development of a Model Municipal Solid Waste
Authors: Indrasenan Thusyanthan N , Gopal Madabhushi SP , Singh S
Published: March 2009

This paper presents the development of a model waste that has physical properties similar to those reported by investigators for municipal solid waste (MSW). The model waste was developed using a mixture of peat, E-grade kaolin clay and fraction-E fine sand. Unit weight, compressibility, and shear strength characteristics of the model waste were experimentally determined and shown to match well with those reported for MSW.
An Improved Oedometer Apparatus to Measure Lateral Stress During Testing
Authors: Gareau LF , Molenkamp F , Sharma J
Published: March 2009

Soils which have been subjected to complex geological stress histories (such as glaciation) exhibit incongruent geotechnical properties when tested in the oedometer. A new oedometer apparatus has been developed to permit measurement of anisotropic horizontal stress reactions during vertical loading. The objective of the apparatus is to assess how different geological stresses relate to present state properties. The apparatus has been tested using laboratory prepared samples of kaolin and thin tube core samples of Pot Clay from the north Netherlands. These results indicate that the new apparatus can measure isotropic and anisotropic lateral stresses with reasonable repeatability. Also, the orientation of maximum and minimum horizontal stresses can be calculated if oriented core samples are used. Results from the Pot Clay indicate anisotropic horizontal stresses which are related to the known glacial stress history.
Development of a Direct Shear Apparatus with Rock Joints and Its Verification Tests
Authors: Kim D-Y , Chun B-S , Yang J-S
Published: March 2009

A new direct shear apparatus for natural rock joints and artificial joints has been developed that can achieve constant normal stress (CNS), constant normal load (CNL), and infinite normal stiffness (INS). The CNS condition during shear is maintained by changing the normal load corresponding to a reduced contact area with shear displacements. The deformation of the apparatus due to normal loading is excluded in order to obtain the pure displacement of the specimen. The deformation of the apparatus due to shear loading included in the total displacement is also minimized by measuring the relative displacement between the upper and lower shear boxes. Four degrees of freedom are employed in this study: two transitional motions of the upper and lower shear boxes and two rotational motions of the upper shear box. A series of tests for CNS, CNL, and INS conditions have been performed to verify the accuracy of the control system for the same roughness. Other tests have also been performed on saw-tooth joints with asperities having inclinations of 16.7° and 26.6°, and JRC values of 10 and 15 were obtained from the tests, respectively. The maximum dilation angle occurs at peak shear strength, which shows a good agreement with Barton's model.