bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavioural development of school-aged children who live around a multi-metal sulphide mine in Guangdong province, China: a cross-sectional study
Authors: Bao Qing-Song , Lu Ci-Yong , Song Hong , Wang Mao , Ling Wenhua , Chen Wei-Qing , Deng Xue-Qing , Hao Yuan-Tao , Rao Shaoqi
Published: July 2009

Background

The deleterious biological effects of low-level, long-term exposure to heavy metals are well known, and children are the most susceptible population. Dabaoshan Mine in the southeast of Guangdong Province is at high risk of discharging multi-metals pollutants into a local river (Hengshihe) and the surrounding area. The present study aimed to estimate relationships between measured multi-metal exposures and the presence of behavioural problems for the school-aged children in the polluted area.

Methods

A cross-sectional study was performed. Children aged 7–16 years living in three villages of the Hengshihe area with different degrees of heavy-metal pollution participated in this study. Local environmental samples (water and crops) and children's hair were collected, and concentrations of heavy metals were determined. The Child Behaviour Check-list (CBCL) was used to assess the presence of behaviour problems. General linear regression was used to analyze the contribution of hair metals to each CBCL subscale with adjustment for socio-demographic confounding factors.

Results

Multiple regression analyses revealed significant effects of hair lead, cadmium and zinc levels on CBCL subscales. Log-transformed hair lead, cadmium and zinc levels accounted for an incremental of 8% to 15% variance in anxious/depressed, withdrawn, somatic complaints, social problems, thought problems, attention problems, delinquent behaviour and aggressive behaviour. The concurrent log-transformed hair lead and zinc levels were strongly associated with all subscales while the concurrent log-transformed hair cadmium was only significantly associated with withdrawn, social problems and attention problems.

Conclusion

This study reveals that heavy metal exposure was associated with increased risk of behavioral problems for school-aged children.
The association between Colombian medical students' healthy personal habits and a positive attitude toward preventive counseling: cross-sectional analyses
Authors: Duperly John , Lobelo Felipe , Segura Carolina , Sarmiento Francisco , Herrera Deisy , Sarmiento Olga L , Frank Erica
Published: July 2009

Background

Physician-delivered preventive counseling is important for the prevention and management of chronic diseases. Data from the U.S. indicates that medical students with healthy personal habits have a better attitude towards preventive counseling. However, this association and its correlates have not been addressed in rapidly urbanized settings where chronic disease prevention strategies constitute a top public health priority. This study examines the association between personal health practices and attitudes toward preventive counseling among first and fifth-year students from 8 medical schools in Bogotá, Colombia.

Methods

During 2006, a total of 661 first- and fifth-year medical students completed a culturally adapted Spanish version of the "Healthy Doctor = Healthy Patient" survey (response rate = 78%). Logistic regression analyses were used to assess the association between overall personal practices on physical activity, nutrition, weight control, smoking, alcohol use (main exposure variable) and student attitudes toward preventive counseling on these issues (main outcome variable), stratified by year of training and adjusting by gender and medical training-related factors (basic knowledge, perceived adequacy of training and perception of the school's promotion on each healthy habit).

Results

The median age and percentage of females for the first- and fifth-year students were 21 years and 59.5% and 25 years and 65%, respectively. After controlling for gender and medical training-related factors, consumption of ≥ 5 daily servings of fruits and/or vegetables, not being a smoker or binge drinker were associated with a positive attitude toward counseling on nutrition (OR = 4.71; CI = 1.6–14.1; p = 0.006 smoking (OR = 2.62; CI = 1.1–5.9; p = 0.022), and alcohol consumption (OR = 2.61; CI = 1.3–5.4; p = 0.009), respectively.

Conclusion

As for U.S. physician and medical students, a positive association was found between the personal health habits of Colombian medical students and their corresponding attitudes toward preventive counseling, independent of gender and medial training-related factors. Our findings, the first relating to this association in medical students in developing regions, also suggest that within the medical school context, interventions focused on promoting healthy student lifestyles can potentially improve future physician's attitudes toward preventive counseling.
Capacity mapping of national ethics committees in the Eastern Mediterranean Region
Authors: Abou-Zeid Alaa , Afzal Mohammad , Silverman Henry J
Published: July 2009

Background

Ethics issues in the areas of science, technology and medicine have emerged during the last few decades. Many countries have responded by establishing ethics committees at the national level. Identification of National Ethics Committees (NECs) in the Eastern Mediterranean (EM) region and the extent of their functions and capacity would be helpful in developing capacity building programs that address the needs of these committees. Accordingly, we conducted a survey to determine the characteristics of existing NECs in the EM region.

Methods

We developed a questionnaire to collect information on different aspects of NECs. The questionnaire was sent to the WHO country office in each of the 22 Member States in the EM region. We used descriptive statistics to analyze the data.

Results

We obtained responses from 77% (17/22) of the EM countries; 88% (15/17) of the countries stated they had NECs. Of these NECs, 40% (6/15) were involved in the ethics of science and technology, 73% (11/15) in medical ethics, and 93% (14/15) in medical research ethics; 10 NECs stated they reviewed research protocols. Of the respondent NECs, 25% (4/15) met at least on a monthly basis. Regarding training, 21% of the members from all of the NECs had received formal training in ethics; 53% (8/15) of the NECs had none of their members with formal training in ethics. Regarding support, 33% (5/15) received financial support and 60% (9/15) had administrative support.

Conclusion

While many countries in the EM region report the existence of NECs, many meet infrequently, many have members without formal training in ethics, and many lack important financial and administrative resources. Further efforts should be directed towards capacity building programs that include ethics training and provision of important infrastructure resources for these committees.
Survivin counteracts the therapeutic effect of microtubule de-stabilizers by stabilizing tubulin polymers
Authors: Cheung Chun Hei Antonio , Chen Huang-Hui , Kuo Ching-Chuan , Chang Chi-Yen , Coumar Mohane S , Hsieh Hsing-Pang , Chang Jang-Yang
Published: July 2009

Background

Survivin is a dual function protein. It inhibits the apoptosis of cells by inhibiting caspases, and also promotes cell growth by stabilizing microtubules during mitosis. Over-expression of survivin has been demonstrated to induce drug-resistance to various chemo-therapeutic agents such as cisplatin (DNA damaging agent) and paclitaxel (microtubule stabilizer) in cancers. However, survivin-induced resistance to microtubule de-stabilizers such as Vinca alkaloids and Combretastatin A-4 (CA-4)-related compounds were seldom demonstrated in the past. Furthermore, the question remains as to whether survivin plays a dominant role in processing cytokinesis or inhibiting caspases activity in cells treated with anti-mitotic compounds. The purpose of this study is to evaluate the effect of survivin on the resistance and susceptibility of human cancer cells to microtubule de-stabilizer-induced cell death.

Results

BPR0L075 is a CA-4 analog that induces microtubule de-polymerization and subsequent caspase-dependent apoptosis. To study the relationship between the expression of survivin and the resistance to microtubule de-stabilizers, a KB-derived BPR0L075-resistant cancer cell line, KB-L30, was generated for this study. Here, we found that survivin was over-expressed in the KB-L30 cells. Down-regulation of survivin by siRNA induced hyper-sensitivity to BPR0L075 in KB cells and partially re-stored sensitivity to BPR0L075 in KB-L30 cells. Western blot analysis revealed that down-regulation of survivin induced microtubule de-stabilization in both KB and KB-L30 cells. However, the same treatment did not enhance the down-stream caspase-3/-7 activities in BPR0L075-treated KB cells. Translocation of a caspase-independent apoptosis-related molecule, apoptosis-inducing factor (AIF), from cytoplasm to the nucleus was observed in survivin-targeted KB cells under BPR0L075 treatment.

Conclusion

In this study, survivin plays an important role in the stability of microtubules, but not with caspases inhibition. Over-expression of survivin counteracts the therapeutic effect of microtubule de-stabilizer BPR0L075 probably by stabilizing tubulin polymers, instead of the inhibition of caspase activity in cancer cells. Besides microtubule-related caspase-dependent cell death, caspase-independent mitotic cell death could be initiated in survivin/BPR0L075 combination treatments. We suggest that combining microtubule de-stabilizers with a survivin inhibitor may attribute to a better clinical outcome than the use of anti-mitotic monotherapy in clinical situations.
Novel swing-assist un-motorized exoskeletons for gait training
Authors: Mankala Kalyan K , Banala Sai K , Agrawal Sunil K
Published: July 2009

Background

Robotics is emerging as a promising tool for functional training of human movement. Much of the research in this area over the last decade has focused on upper extremity orthotic devices. Some recent commercial designs proposed for the lower extremity are powered and expensive – hence, these could have limited affordability by most clinics. In this paper, we present a novel un-motorized bilateral exoskeleton that can be used to assist in treadmill training of motor-impaired patients, such as with motor-incomplete spinal cord injury. The exoskeleton is designed such that the human leg will have a desirable swing motion, once it is strapped to the exoskeleton. Since this exoskeleton is un-motorized, it can potentially be produced cheaply and could reduce the physical demand on therapists during treadmill training.

Results

A swing-assist bilateral exoskeleton was designed and fabricated at the University of Delaware having the following salient features: (i) The design uses torsional springs at the hip and the knee joints to assist the swing motion. The springs get charged by the treadmill during stance phase of the leg and provide propulsion forces to the leg during swing. (ii) The design of the exoskeleton uses simple dynamic models of sagittal plane walking, which are used to optimize the parameters of the springs so that the foot can clear the ground and have a desirable forward motion during walking. The bilateral exoskeleton was tested on a healthy subject during treadmill walking for a range of walking speeds between 1.0 mph and 4.0 mph. Joint encoders and interface force-torque sensors mounted on the exoskeleton were used to evaluate the effectiveness of the exoskeleton in terms of the hip and knee joint torques applied by the human during treadmill walking.

Conclusion

We compared two different cases. In case 1, we estimated the torque applied by the human joints when walking with the device using the joint kinematic data and interface force-torque sensors. In case 2, we calculated the required torque to perform a similar gait only using the kinematic data collected from joint motion sensors. On analysis, we found that at 2.0 mph, the device was effective in reducing the maximum hip torque requirement and the knee joint torque during the beginning of the swing. These behaviors were retained as the treadmill speed was changed between 1–4 mph. These results were remarkable considering the simplicity of the dynamic model, model uncertainty, non-ideal spring behavior, and friction in the joints. We believe that the results can be further improved in the future. Nevertheless, this promises to provide a useful and effective methodolgy for design of un-motorized exoskeletons to assist and train swing of motor-impaired patients.
Characterization of subcellular localization of duck enteritis virus UL51 protein
Authors: Shen Chanjuan , Guo Yufei , Cheng Anchun , Wang Mingshu , Zhou Yi , Lin Dan , Xin Hongyi , Zhang Na
Published: July 2009

Background

Knowledge of the subcellular localization of a protein can provide useful insights about its function. While the subcellular localization of many alphaherpesvirus UL51 proteins has been well characterized, little is known about where duck enteritis virus (DEV) UL51 protein (pUL51) is targeted to. Thus, in this study, we investigated the subcellular localization and distribution of DEV pUL51 by computer aided analysis, as well as indirect immunofluorescence (IIF) and transmission immunoelectron microscopy (TIEM) approaches in DEV-infected cells.

Results

The DEV UL51 gene product was identified as an approximate 34 kDa protein in DEV-infected cells analyzed by western blotting. Computer aided analysis suggested that DEV pUL51 is not targeted to the mitochondrial, extra-cellular or nucleus, but be targeted to the cytoplasmic in host cells, more specifically, palmitoylation of the pUL51 through the N-terminal cysteine at position 9 makes membrane association and Golgi localization possible. Using IIF analysis, we found that DEV pUL51 was first detected in a juxtanuclear region of DEV-infected cells at 9 h postinfection (p.i.), and then was detected widely distributed in the cytoplasm and especially was stronger in the juxtanuclear region from 12 to 60 h p.i. TIEM analysis revealed that DEV pUL51 was mainly associated with cytoplasmic virions and also with some membranous structure near the pUL51-specific immuno-labeling intracellular virion in the cytoplasmic vesicles; moreover, the pUL51 efficiently accumulated in the Golgi apparatus at first, and then was sent to the plasma membrane from the Golgi by some unknown mechanism.

Conclusion

In this work, we described the basic characteristics of pUL51 subcellular localization and distribution for the first time. From these results, we concluded that palmitoylation at the N-terminal cysteine, which is conserved in all alphaherpesvirus UL51 homologs, is required for its membrane association and Golgi localization, and the pUL51 mainly localized to the juxtanuclear region of DEV-infected cells, as well seemed to be incorporated into mature virions as a component of the tegument. The research will provide useful clues for DEV pUL51 functional analysis, and will be usefull for further understanding the localization properties of alphaherpesvirus UL51 homologs.
Geochemical Characteristics of Rare Earth Elements in Petroleum and Their Responses to Mantle-Derived Fluid: An Example from the Dongying Depression, East China
Authors: Zhang Liuping , Zhao Yingquan , Jin Zhijun , Bai Guoping , Yang Lei
Published: July 2009

This paper studies the characteristics of rare earth elements (REEs) in petroleum, in order to investigate the influence of mantle-derived fluid on petroleum. Oil and gas samples were collected from the petroliferous Dongying Depression, East China. Basic igneous rocks and mantle-derived fluid have been found along the fault belts that cut to the basement in the active areas of this depression. The mudstone-normalized REE patterns of petroleum from regions that have not been affected by mantle-derived fluids are evidently characterized by enrichments in a) Nd, Eu, Tb, and Ho, the middle REEs (MREEs) that contain an even number of f-electrons, and b) Er, Tm, Yb and Lu, the heavy REEs (HREEs). The introduction of mantle-derived fluids into the basin is supported by helium isotope composition of the natural gas from the region. MREE anormalies and HREE enrichment are diminished in these affected areas, as compared to oils from the unaffected areas. Mudstone-normalizd Eu/Eu* and Lu/Er were selected to describe this diminishment. The correlation between observed changes in REE patterns in the oils and helium isotope ratios in co-produced natural gases suggests that the changes were likely caused by the mantle-derived fluid and that REEs in petroleum may potentially act as a tracer for understanding the influence of the mantle-derived fluid on oil, when combined with 3He/4He. Further more, the relationship between mudstone-normalized Eu/Eu* and Lu/Er values REEs in oil may help to identify whether the mantle-derived fluids influence on oil or on hydrocarbon generation.
Tectonic Background of Ordos Basin and its Controlling Role for Basin Evolution and Energy Mineral Deposits
Authors: Liu Chiyang , Zhao Hongge , Sun Yuzhuang
Published: July 2009

In order to study the relationship of energy mineral deposits and tectonic movements in Ordos basin, more than 82 samples were taken for determination of apatite and zircon fission tracks. Furthermore, 93 apatite and zircon fission tracks have been selected from other publications. According to these data and other geological background, the evolution of Ordos basin can be divided into 4 stages, and the reformation of the basin can be divided into 5 stages. The basin formation and development were controlled by regional geodynamics. Oil, coal, nature gas and uranium deposits were formed in deferent stages. In the same time, 140 samples were taken and analyzed by organic and inorganic geochemical methods. The results indicate that coal and source rocks generate oil and natural gas, which migrate through reservoir rocks. Oil and natural gas changed the redox conditions of sediments and let uranium accumulate in the sandstones.
A Comparison of Geochemical Features of Extracts from Coal-Seams Source Rocks with Different Polarity Solvents
Authors: Chen Jianping , Deng Chunping , Wang Huitong
Published: July 2009

There exists a great difference in group-type fractions and biomarker distributions of chloroform extracts from coals and coal-seams oils, which makes the source identification of coal-seams oils in sedimentary basins rather difficult. The experiment, in which four different polarity solvents, n-hexane, benzene, dichloromethane and chloroform, were used to extract 9 coal-seams source rocks and 3 typical lacustrine source rocks, showed that the yield of extracts increased gradually with increasing solvent polarity, among which obviously the proportion of n-alkanes gradually decreased and the composition of the n-hexane extract was the most similar to that of coal-formed oils. Although some obvious differences existed in yields and compositions of the extracts obtained by different solvents, the entire distribution features of their n-alkanes, isoprenoids and sterane and terpane biomarkers remained, in general, similar, showing no distinct enrichment or depletion for a certain fraction by any solvent. The compositional analysis on n-hexane and chloroform extracts showed that the absolute amount (concentration) of biomarkers was relatively low for the n-hexane extract but comparatively high for the chloroform extract, this difference became great among coal-seams source rocks but small among lacustrine mudstones. The statistical analysis on the relative amount of the 18 major biomarkers in n-hexane and chloroform extracts from 10 source rock samples showed that extracts with a proportional error for the same biomarker of less than 5% (including the analytical error) accounted for 84% while those with a proportional error over 10% amounted to below 5%. This suggested that the difference in solvent polarity would lead to variations in both the relative amount of n-alkanes and the absolute amount of biomarkers for the extract from coals but could not induce variations in the distributional features and mutual ratios of biomarkers for the same extract on condition of using common solvents, consequently, the outcome of oil-source correlation made by these biomarkers will be independent of variations in amounts of saturates and biomarkers arising from solvent polarity. Therefore, biomarkers obtained from organic-rich source rocks including coals by the extraction with the commonly used chloroform solvent can be applied for the oil-source correlation of coal-seams petroliferous basins.
Removal of Methylene Blue from Aqueous Solution by Non-Living Biomass of Marine Algae and Freshwater Macrophyte
Authors: Wang Xue Song , Zhou Ying , Jiang Yu
Published: July 2009

The adsorption of Methylene Blue, a Basic dye, onto the nonliving biomass of marine algae and freshwater macrophyte was investigated by batch experiments. Such adsorption onto both adsorbents was pH-independent. The experimental data were analyzed using pseudo-first-order and pseudo-second-order kinetic equations, the results suggesting that the data were described well by both models. Intraparticle diffusion played an important role in the mass-transfer process. Methylene Blue adsorption onto both adsorbents at 20°C was also evaluated by the Freundich and Langmuir isotherms. The maximum adsorption capacities were 155.31 mg/g for Laminaria japonica (LJ) biomass and 150.39 mg/g for alligator weed (AW) biomass, respectively. The effects of adsorbent concentration and ionic strength on Methylene Blue adsorption were also investigated. The adsorbents investigated could serve as low-cost adsorbents for removing Methylene Blue from aqueous solution.
Sulphated Oxides of Titanium Prepared from Titanium Ethoxide: Surface and Related Properties
Authors: Ramadan Adham R. , Yacoub Nahed , Amin Haguer , Ragai Jehane
Published: July 2009

Titanium oxides, with moderately high surface areas exhibiting a mixed mesoporous/microporous texture, were prepared from titanium ethoxide. The porosity seemed to stem from the loss of volatile components from the inner coordination sphere of the titanium ions. After impregnation with sulphate groups, a general decrease in surface area was observed. This decrease was more drastic at higher temperatures when the sulphate ions are in a bidentate state of ligation. A high sulphate concentration led to a distinctive decrease in the total pore volume and to the loss of the microporous texture. Micropore blocking appeared to be due to the presence of the bidentate sulphate groups. The latter are responsible for the higher surface acidities displayed by the sulphated oxides.
Enhancing the Frequency Range of Measurement for an Accelerometer
Authors: Badri Abdellatef , Sinha Jyoti K. , Albarbar Alhussein
Published: July 2009

A simple method is proposed here to enhance the frequency range of measurement for an accelerometer based on laboratory experiments. The proposed method generates a Characteristic Function (CF) in frequency domain for the test accelerometer by comparing with other high frequency accelerometers such that the CF can be used to correct the amplitude and phase measurement beyond the linearity frequency range for the test accelerometer.
Thermodynamics Performance Study on Water Source Heat Pump in Variant Operating Condition
Authors: Zheng Guozhong , Jing Youyin
Published: July 2009

Water source heat pumps have outstanding advantages: significant energy conservation, working stability and notable pollution reduction. In this paper, the benefits and features of the water source heat pump are described. Then the methodology for studying the thermodynamics performance in variant conditions is described and the thermodynamics analysis of a specific water source heat pump is presented based on the first law of thermodynamics and exergy analysis theory to study the thermodynamics performance in variant condition. Coefficient of Performance (COP) and exergy efficiency in variant operating condition are calculated. The relation of COP and exergy efficiency with the outlet temperature of the chilled water and the inlet temperature of the cooling water are respectively studied. The operating strategies of both summer and winter condition are then concluded. Finally, the thermodynamics performance of the water source heat pump is compared with the other common refrigerating and heating equipments. It is concluded that the water source heat pump has great advantage over others in terms of energy saving. It is expected that the study would be beneficial to the researchers and engineers.
James Hansen's 1988 Predictions Compared to Observations
Authors: McIntyre Dale R.
Published: July 2009

All James Hansen's 1988 scenarios overestimated actual temperature change substantially even with anthropogenic greenhouse gas (AGHG) emission assumptions that underestimated actual emissions. With no AGHG reductions at all, observed temperature change is now well below Hansen's 1988 calculations for a world with “drastically reduced” emissions. Therefore any economic hardships incurred to implement Hansen's emissions reduction scenarios B or C would have been money wasted for no benefit.
Recent Climate Observations: Disagreement with Projections
Authors: Stockwell David R.B.
Published: July 2009

The non-linear trend in Rahmstorf et al. [2007] is updated with recent global temperature data. The evidence does not support the basis for their claim that the sensitivity of the climate system has been underestimated.
The Cyclic Behaviour of Reinforced Concrete Chimney Sections with and without Openings
Authors: Wilson John L.
Published: July 2009

The most vulnerable feature of most existing tall reinforced concrete chimneys when subject to severe earthquake excitation is the relative weakness of the sections around the openings near the chimney base. This paper documents an experimental study undertaken to investigate the cyclic behaviour of typical chimney sections with openings orientated to be bending critical and shear critical and the results are compared with previous tests with no openings. Significantly, no such cyclic tests have been previously been completed. The experimental results presented include; failure mode, over-strength factor, ultimate curvature, available ductility, hysteretic behaviour and strain distribution and the results are compared with some predictive analytical section models and design guidelines. The research indicated that chimney sections with openings were not brittle, but were significantly less ductile than sections without openings. The paper is relevant for both assessing existing chimney stacks and for the design of new chimneys in the vicinity of openings.
Safety Assessment Procedure for a Cracked Square Hollow Section (SHS) Y-joint
Authors: Lie Seng Tjhen , Yang Zhengmao
Published: July 2009

In this paper, an accurate crack model of a square hollow section (SHS) welded Y-joint is proposed, and a high quality finite element mesh is generated. Based on this numerical model, the load-displacement curves and the stress intensity factors (SIFs) along the crack front are calculated. It is shown that the highest value of the stress intensity factor is always located at the chord corner. From the full-scale static strength test carried out on the cracked SHS Y-joint, it was found that ductile crack tearing initiated at the crack front parallel to the chord side wall where the fracture toughness is smaller, and not from the crack front around the corner where the SIF is the highest. Using the plastic collapse load obtained via the twice elastic compliance technique and the fracture toughness obtained from the Charpy V-notch and CTOD tests, the assessment points of Kr and Lr are calculated and plotted on the BS7910 (2005) Level 2A Failure Assessment Diagram (FAD) curve, thus demonstrating its usage. It shows that the standard curve gives a conservative assessment for the cracked SHS Y-joint subjected to brace end axial loads.
Seismic Retrofit of Brittle and Low Strength RC Columns Using Fiber Reinforced Polymer and Cementitious Composites
Authors: Ilki Alper , Demir Cem , Bedirhanoglu Idris , Kumbasar Nahit
Published: July 2009

The objective of this study is to investigate the seismic performance of reinforced concrete columns constructed with low quality of concrete and insufficient transverse reinforcement before and after retrofitting. Totally twenty nearly full size specimens with rectangular cross-section were tested under constant axial load and reversed cyclic lateral loads. Both longitudinal and transverse reinforcements were plain bars. Ten of the specimens had insufficient lap splice length of longitudinal reinforcement between stories as well. Both pre-damaged and undamaged columns with these deficiencies were retrofitted with FRP (fiber reinforced polymer) composite jackets or prefabricated HPFRCC (high performance fiber reinforced cementitious composite) panels. The test results showed that all reference specimens, which were not retrofitted, failed with a premature loss of performance either due to buckling of longitudinal reinforcement or loss of bond, while retrofitted ones exhibited a significantly superior performance, particularly in terms of ductility. It should be noted that the enhancement in performance was less remarkable for the specimens with inadequate lap splice lengths. An analytical work is also presented for prediction of the behavior of the specimens both for continuous and lap spliced longitudinal reinforcement cases.
Effects of Tenon Depths and Bolt Constraint Conditions on the Mechanical Behavior of Semi-Rigid Joints of Wooden Historical Buildings
Authors: Li Yeou-Fong , Tsai Ming-Jer , Liao Cheng-Nan , Tsai Jenn-Hui
Published: July 2009

The effects of tenon depths and bolt constraint conditions on the mechanical behavior of semi-rigid joints of wooden historical buildings in Taiwan were examined. Monotonic and cyclic loading tests were performed on the joint specimens to obtain the moment-rotation relationship of wooden semi-rigid joints. The results showed that the wood joints could bear external lateral forces when they reached their yield strength and would not rupture immediately. The smaller the d/h (ratio of the tenon depth to beam height) value, the easier the joints collapsed during monotonic loading. The larger the d/h value, the larger the differences of the ultimate strengths. The tenon depth could be increased to strengthen the ultimate moment of the bolt. Comparing the experimental results and the results predicted by the Colson and Louveau model, the model with the proposed parameters could simulate the experimental results with a good accuracy, and the average absolute error was less than 7.6%.
Boundary Detailing of Coupled Core Wall System Wall Piers
Authors: Fortney Patrick J. , Shahrooz Bahram M.
Published: July 2009

The seismic provisions of ACI 318–08 permit two different procedures for evaluating the need for “special” boundary elements in structural walls. The first method is based on an approximation of the maximum fiber concrete compressive stresses calculated using wall gross section properties and an assumed linear distribution of stresses over the depth. The second method places a limit on the compression zone depth of the wall. These methods are based on studies of uncoupled continuous walls, and their applicability to coupled walls is unclear. A parametric study consisting of eight coupled core wall buildings with varying geometric dimensions is presented. The states of concrete stress, strain, and compression zone depth in the wall piers at code level forces are investigated. Based on evaluation of the two procedures permitted by ACI 318–08, it is concluded that neither procedure is appropriate for wall piers in coupled core wall systems. Cross-sectional fiber analysis is a more effective evaluation tool.
A Simultaneous Coupled Nonlinear Algorithm for the Analysis of Steel Frames with Flexible Joints considering Joint Unloading
Authors: Abolmaali Ali , Le Tri , Godswel Zachary
Published: July 2009

This paper presents a finite element plasticity-based computer algorithm to analyze steel frames with flexible joints under static proportional loading, unloading, and reverse loading. Each connection mechanism is modeled using a rotational spring element with two nodes of identical spatial coordinates and the same translational degrees of freedom and different rotational degrees of freedom for modeling the relative rotation of the beam and ends of the connection. Instead of using a classical coupled nonlinear algorithm for the connection element and member geometric stiffness, a unique solution method is introduced that simultaneously iterates to find the incremental connection element and member geometric stiffness of the structure through solving the nonlinear system equation. To model unloading and reverse loading at the joints between beams and columns, a three-parameter, kinematics hardening model for moment-rotation behavior is considered. For proof-of-concept, a one-story, one-bay frame with two connections is considered for parametric study. It is shown that different connection constitutive equation (moment-rotation characteristic) in a frame could cause moment reversal in some connection(s).
Effects of Dynamic Excitations Due to Very Fast Trains on the Instability of Railway Rock Ballast
Authors: Tran Danh
Published: July 2009

It is well known that during the passage of very fast trains (VFT), ballast aggregates can vibrate violently resulting in ballast instability. A simple two dimensional model of the railway track system was proposed, consisting of a sleeper, loose ballast rocks in contact under Coulomb dry friction, compacted rocks and soil foundation. The dynamic behaviour of the system caused by the transient axle load of a single bogie was investigated by explicit finite element method (FEM). It was found that the sleeper exhibits a residual settlement due to irreversible displacement of the ballast rock aggregates. The settlement is maximum at train speed around the Rayleigh wave speed. Similar behaviour was observed for transient force due to two and four closest set of bogies. The simple model shows promising results in investigating this non-linear, irreversible phenomenon and should be extended to more complicated representation of the ballast aggregates under transient forces due to the whole train.
The Influence of Non-Rigid Floor Structures on Facade Rigger Braced High-Rise Trussed Frames
Authors: Hoenderkamp J.C.D.
Published: July 2009

This paper presents a graphical method of analysis for preliminary design of horizontally loaded tall buildings which are laterally supported by vertical trussed frames and horizontal off-set riggers which are located in the exterior or facade skeletal frame structures in the direction of the lateral loading. The interaction between the trussed frames and these facade riggers is through the two floor structures adjacent to the top and bottom cords of the riggers. The method of analysis requires the calculation of seven planar stiffness parameters: bending and shear stiffness of the vertical trussed frames, the horizontal off-set riggers and the floor structures in addition to the bending stiffness of the exterior skeletal frame structures which support the riggers. The method allows a graphical procedure for obtaining the optimum level of the facade riggers in addition to a rapid assessment of the influence of the floor structures and facade riggers on the performance of the high-rise structure such as the reduction in lateral deflection at the top and the overturning moment at the base of the trussed frames.
Faraway, Yet So Close: Organizations in Demographic Flux
Authors: Pennings Johannes M. , Wezel Filippo Carlo
Published: July 2009

Change in firm governance is often associated with inbound and outbound movements of key decision makers. This research extends that observation by treating mobility as a trigger of demographic change in management teams that, in turn, influences organizational survival. Mobility occasions transformations in demographic profiles both within a firm and among firms sharing a competitive arena. In the former case, shifts in diversity may alter the quasi-resolution of conflict achieved by the firm's upper echelons, or, conversely, serve to inject novel views and ideas. In the latter case, migration may modify the demographic overlap among firms and thus rearrange their competitive positioning. We present here an empirical test of this two-pronged manifestation of demographic change and stress the moderating roles of team age and competitive intensity.
Power Asymmetry and Learning in Teams: The Moderating Role of Performance Feedback
Authors: Van der Vegt Gerben S. , de Jong Simon B. , Bunderson J. Stuart , Molleman Eric
Published: July 2009

Past research suggests that power asymmetry within teams can have a stifling effect on team learning and performance. We argue here that this effect is contingent on whether power advantages within a team are used to advance individual or collective interests. This study considers the moderating role of one factor that can influence the individual or collective orientation of team members—the type of performance feedback that a team receives. We propose that whereas individual feedback reinforces the negative effects of power asymmetry on team learning, group feedback fosters a collective orientation within a team that transforms power differences into a stimulus for team learning. Analysis of multisource, multimethod data obtained from 218 individuals in 46 teams provided support for these hypotheses. Results also suggested that team learning mediated the relationship between power asymmetry and team performance. These findings suggest that power asymmetry can be a resource for and not just an obstacle to team learning in power-asymmetric teams.
The Effect of Total Knee Replacement on Employment in Patients Under 60 Years of Age
Authors: Lyall H , Ireland John , El-Zebdeh MY
Published: July 2009

INTRODUCTION

The effect of primary total knee replacement on the employment status of 56 patients under 60 years of age was examined at a mean follow-up of 64 months.

PATIENTS AND METHODS

A total of 56 primary total knee replacements performed on patients under the age of 60 years by two surgeons between 1996 and 2003 were retrospectively assessed by postal questionnaire. Patients were selected from databases held at Holly House and Newham Hospital NHS Trust.

RESULTS

Overall, 97.5% of patients who were employed before their operation, returned to their previous work. However, in patients not working prior to total knee replacement none were employed after their operation.

CONCLUSIONS

Total knee replacement may be a valuable tool to help some patients to continue working but may not affect patients who are already unemployed.
The Role of Routine Assays of Serum Amylase and Lipase for the Diagnosis of Acute Abdominal Pain
Authors: Sutton Paul A , Humes David J , Purcell Gemma , Smith Janette K , Whiting Frances , Wright Tom , Morgan Linda , Lobo Dileep N
Published: July 2009

INTRODUCTION

We aimed to evaluate the role of routine measurements of serum amylase and lipase in the diagnosis of acute abdominal pain.

PATIENTS AND METHODS

We identified all patients who had serum amylase and lipase assays over a 62-day period at a single university teaching hospital and reviewed their case notes.

RESULTS

We excluded 58 of the 1598 patients on grounds of ineligibility (< 18 years of age and those transferred from other hospitals). A complete data set was obtained for 1520 (98.7%) of the remaining 1540 patients. Only 9.1% of requests were based on a clinical suspicion of acute pancreatitis. Of the 44 (2.9%) patients who had acute pancreatitis, only 28 (63.6%) had an associated rise in serum amylase and/or lipase 3 times above the maximum reference range, the remainder being diagnosed radiologically. At this cut-off range, the sensitivity and specificity for serum amylase were 50% and 99%, and those for serum lipase 64% and 97%, respectively.

CONCLUSIONS

Routine measurements of serum amylase and lipase are unhelpful in the diagnosis of acute abdominal pain unless there is clinical suspicion of acute pancreatitis. In these patients, assay of lipase alone is preferable to assay of amylase alone or both enzymes.
A Second National Survey of Health-Related Quality of Life Questionnaires in Head and Neck Oncology
Authors: Kanatas Anastasios N , Mehanna Hisham M , Lowe Derek , Rogers Simon N
Published: July 2009

INTRODUCTION

With an increasing number of publications on health-related quality of life (HRQOL) following head and neck cancer, the recognition of a number of well-validated questionnaires and a growing awareness of the potential role of HRQOL in practice, it was our aim to repeat the survey of 2002 reported in the Annals to see how practice changed.

MATERIALS AND METHODS

A postal survey of members of the British Association of Head and Neck Oncologists was undertaken in January 2006 with reminders sent in February, March and April.

RESULTS

The response was 50% (106 of 210) of which 53% were using or had used HRQOL questionnaires. The main reasons for not using HRQOL questionnaires were that they were too time-consuming or intrusive in a clinic setting and that there was a lack of resources.

CONCLUSIONS

Clinicians still see the use of questionnaires as a research-tool only, rather than an adjunct to giving patient information, promoting choice, and identifying patients with problems. The burden on HRQOL evaluation in routine clinical practice remains a substantial barrier. Advances with IT support in clinic should make it easier to collect and use these data in the future. As surgeons, we still need to be persuaded of the benefits of HRQOL outcomes in our practice.
Meniscal Allograft Transplantation: A Review of the Current Literature
Authors: Crook TB , Ardolino A , Williams LAP , Barlow IW
Published: July 2009

INTRODUCTION

Patients who have previously undergone meniscectomy are known to potentially suffer subsequent knee problems including degenerative changes. Meniscal transplantation has been proposed as a possble solution to these problems. This article aims to review the current literature to consolidate the evidence surrounding the use of human meniscal allograft transplantation.

MATERIALS AND METHODS

Three databases (PubMed, Embase and Medline) were searched to find English language articles pertaining to meniscal allograft transplantation. Each article was critiqued by two authors using a structured appraisal tool, and stratified according to the level of evidence.

RESULTS

No Level I or II studies were identified. Many studies had small study groups with limited follow-up and patient selection and description of patient factors varied greatly. This made comparing data difficult. There were also very few papers concentrating on isolated meniscal transplantation. Four types of graft are used – fresh, fresh-frozen, cryopreserved and freeze-dried (lyophilised) graft. Cryopreserved and fresh-frozen allografts are deemed most suitable. Most authors advocate the use of non-irradiated grafts from screened donors to reduce transmission of infection. Best results occur when using bony anchors to fix the graft, although this requires accurate graft positioning. Patients have an improved outcome if they have less severe degenerative changes within the knee prior to transplantation.

CONCLUSIONS

No statistically significant studies looking at isolated meniscal transplantations have been found. The evidence suggests that meniscal allograft transplantation provides improvement of pain and function in the short and intermediate term. The effect on future joint degeneration is still unknown. The ideal patient group includes patients less than 40 years of age with knee pain, proven meniscal injury and a normally aligned, stable joint without severe degenerative changes.
Titanium Mini-Plate for Securing Septal Cartilage – A Case of High-Impact Nasal Trauma
Authors: Manuel A , Fishman JM , Majumdar A , Draper MR
Published: July 2009

A technique is presented of securing the cartilaginous nasal septum using titanium mini-plates in the repair of a complex open comminuted type I nasoethmoid fracture, with internal impaction of the external cartilaginous nose. This technique allows primary skin closure and obviates the need for external metal-work and the attendant potential complications.
Military General Surgical Training Opportunities on Operations in Afghanistan
Authors: Brooks Adam J , Ramasamy Arul , Hinsley David , Midwinter Mark
Published: July 2009

INTRODUCTION

In the UK, general surgical specialist trainees have limited exposure to general surgical trauma. Previous work has shown that trainees are involved in only two blunt and one penetrating trauma laparotomies per annum. During their training, nearly half of trainees will not be involved in the surgical management of liver injury, 20% will not undertake a trauma splenectomy and only a quarter will see a trauma thoracotomy. Military general surgical trainees require training in, and exposure to, the surgical management of trauma and specifically military wounding patterns that is not available in the UK. The objective of this study was to determine whether operative workload in the sole British surgical unit in Helmand Province, Afghanistan (Operation HERRICK) would provide a training opportunity for military general surgical trainees.

PATIENTS AND METHODS

A retrospective theatre log-book review of all surgical cases performed at the Role 2 (Enhanced) treatment facility at Camp Bastion, Helmand Province on Operation HERRICK between October 2006 and October 2007, inclusive. Operative cases were analysed for general surgical trauma, laparotomy, thoracotomy, vascular trauma and specific organ injury management where available.

RESULTS

A total of 968 operative cases were performed during the study period. General surgical procedures included 51 laparotomies, 17 thoracotomies and 11 vascular repairs. There were a further 70 debridements of general surgical wounds. Specific organ management included five cases of liver packing for trauma, five trauma splenectomies and four nephrectomies.

CONCLUSIONS

A training opportunity currently exists on Operation HERRICK for military general surgical specialist trainees. If the tempo of the last 12 months is maintained, a 2-month deployment would essentially provide trainees with the equivalent trauma surgery experience to the whole of their surgical training in the UK NHS. Trainees would gain experience in military trauma as well as specific organ injury management.
Sharps Injury Reporting Amongst Surgeons
Authors: Kerr Hui-Ling , Stewart Nicola , Pace Alistair , Elsayed Sherief
Published: July 2009

INTRODUCTION

The aim of this study was to evaluate the level of sharps injury reporting amongst surgeons.

SUBJECTS AND METHODS

A total of 164 surgeons completed a questionnaire on the reporting of sharps injuries, on the reasons for not reporting and their practise of universal precautions.

RESULTS

Out of 164 surgeons, only 25.8% had reported all their injuries, 22.5% had reported some and 51.7% had reported none. The top three reasons for not reporting their injuries included perception of low risk of transmission, not being concerned and no time. Of the respondents, 15.9% practised all three universal precautions of double-gloving, face shields and hands-free technique.

CONCLUSIONS

We showed that despite local trust adherence to Department of Health policy, sharps injury reporting rates are inadequate. Further investment into healthcare worker education as well as a facilitation of the process of reporting may be necessary to improve reporting rates.