bluuebunny/crossref_metadata_2025 huggingface dataset:
Burden of disease from inadequate water, sanitation and hygiene in low‐ and middle‐income settings: a retrospective analysis of data from 145 countries
Authors: Prüss‐Ustün Annette , Bartram Jamie , Clasen Thomas , Colford John M. , Cumming Oliver , Curtis Valerie , Bonjour Sophie , Dangour Alan D. , De France Jennifer , Fewtrell Lorna , Freeman Matthew C. , Gordon Bruce , Hunter Paul R. , Johnston Richard B. , Mathers Colin , Mäusezahl Daniel , Medlicott Kate , Neira Maria , Stocks Meredith , Wolf Jennyfer , Cairncross Sandy
Published: April 2014

Objective

To estimate the burden of diarrhoeal diseases from exposure to inadequate water, sanitation and hand hygiene in low‐ and middle‐income settings and provide an overview of the impact on other diseases.

Methods

For estimating the impact of water, sanitation and hygiene on diarrhoea, we selected exposure levels with both sufficient global exposure data and a matching exposure‐risk relationship. Global exposure data were estimated for the year 2012, and risk estimates were taken from the most recent systematic analyses. We estimated attributable deaths and disability‐adjusted life years (DALYs) by country, age and sex for inadequate water, sanitation and hand hygiene separately, and as a cluster of risk factors. Uncertainty estimates were computed on the basis of uncertainty surrounding exposure estimates and relative risks.

Results

In 2012, 502 000 diarrhoea deaths were estimated to be caused by inadequate drinking water and 280 000 deaths by inadequate sanitation. The most likely estimate of disease burden from inadequate hand hygiene amounts to 297 000 deaths. In total, 842 000 diarrhoea deaths are estimated to be caused by this cluster of risk factors, which amounts to 1.5% of the total disease burden and 58% of diarrhoeal diseases. In children under 5 years old, 361 000 deaths could be prevented, representing 5.5% of deaths in that age group.

Conclusions

This estimate confirms the importance of improving water and sanitation in low‐ and middle‐income settings for the prevention of diarrhoeal disease burden. It also underscores the need for better data on exposure and risk reductions that can be achieved with provision of reliable piped water, community sewage with treatment and hand hygiene.
Culturally articulated neoliberalisation: corporate social responsibility and the capture of indigenous legitimacy in New Caledonia
Authors: Horowitz Leah S
Published: April 2014

This paper expands our understandings of corporate social responsibility (CSR) as a form of roll‐out neoliberalism, building on analyses ofCSRinitiatives as elements of a capitalist system actively working to create its own social regularisation – to secure a socio‐politico‐economic context supporting capitalist development. Using an ethnographic analysis of the rise and fall of an indigenous protest group that targeted a multinational mining project in New Caledonia, this paper has two theoretical aims. First, it builds on literature that analyses neoliberalism as ‘articulating’ with particular politico‐economic conditions in order to argue that such articulation is also, necessarily,cultural. I describe how the mining company undercut and ultimately co‐opted local resistance, largely by successfully capturing culturally‐based ideologies of customary and indigenous legitimacy. Thus, neoliberalisation's articulations may involve attempts to capture not only formal but also informal regulation or regulators, through direct personal benefits and also indirectly through the capture of culturally valued ideologies. These ideologies, in turn, are caught up in culturally grounded hegemonic processes. This leads to the paper's second theoretical aim, which is to explore what happens when different forms of hegemony, based in distinct cultural formations, encounter each other as well as counter‐hegemonic forces. In engaging directly with customary authorities rather than exclusively with activists, the company re‐legitimised itself by delegitimising its activist opponents, repositioning them as subordinates within their own culturally informed social hierarchy, and reinstating customary authorities’ privileged hegemonic status. Thus, multiple, culturally distinct hegemonic processes may co‐exist and interact; here, they reinforced each other by suppressing counter‐hegemonic activities. However, some customary authorities still sympathised with the protestors’ aims and perceived potential threats from the company's expanding economic power. I end by suggesting that counter‐hegemonic possibilities reside in the perpetual dynamism of cultures.
Import Churning and Export Performance of Multi‐product Firms
Authors: Damijan Jože P. , Konings Jozef , Polanec Sašo
Published: May 2014

This paper analyses the impact of churning in the imported varieties of capital and intermediate inputs on firm export scope and productivity. Using detailed data on imports and exports at the firm‐product‐market level, we document substantial churning in both imports and exports for Slovenian manufacturing firms in the period 1994–2008. On average, a firm changes about one‐quarter of imported and exported product‐markets every year, while gross churning in terms of added and dropped product‐markets is almost three times higher. A substantial share of this product churning is due to simultaneous imports and exports of firms in identical varieties within the same CN‐8 product code (so called pass‐on‐trade). We find that churning in imported varieties is far more important than reduction in tariffs or declines in import prices for firms’ productivity growth and increased export product scope. We also find gross churning has a bigger impact on firm productivity improvements by a factor of more than 10 in comparison with net churning. Both adding and dropping of imported input varieties thus seem to be of utmost importance for firms aiming to optimise their input mix towards their most valuable inputs. These effects are further enhanced when excluding simultaneous trade in identical varieties, suggesting that pass‐on‐trade has less favourable effects on firms’ long‐run performance than regular trade.
Electroretinogram evaluation of equine eyes with extensive ‘bullet‐hole’ fundic lesions
Authors: Allbaugh Rachel A. , Ben‐Shlomo Gil , Whitley R. David
Published: April 2014

Objective

To evaluate the impact of extensive bullet‐hole nontapetal fundic lesions in horses on retinal function as measured by full‐field electroretinography (ERG).

Materials and Methods

Full‐fieldERGwas performed on two horses with numerous bullet‐hole lesions in the nontapetal fundus of both eyes. TheERGwas first recorded from the eye with the more extensive lesions in response to a low‐intensity light stimulus (0.03 cd s/m2) that was given at times (T)T = 5, 10, 15, 20 min of dark adaptation. Consecutively, combined rod–cone response was evaluated bilaterally in response to high‐intensity light stimulus (3 cd s/m2), followed by cone function evaluation by flicker stimulus (3 cd s/m2at 30 Hz). Off‐line analysis of theERGrecordings was then performed.

Results

Despite extensive bullet‐hole lesions in the nontapetal fundus bilaterally in both horses, retinal function as measured byERGdid not show any observable deficits. The b‐wave amplitude of the full‐fieldERGincreased continuously from 5 to 20 min of dark adaptation peaking at 446 μv and 377 μv for horse number 1 and 2, respectively. The b‐wave amplitudes of the combined rod–cone response wereOS‐ 459 μv andOD‐ 392 μv for horse number 1 andOS‐ 491 μv andOD‐ 608 μv for horse number 2. The amplitude of the flickerERGfor horse number 1 wasOS‐ 86 μv andOD‐ 110 μv and for horse number 2,OS‐ 80 μv andOD‐ 74 μv.

Conclusions

Extensive bullet‐hole chorioretinal lesions do not appear to compromise outer retinal function in these horses.
Surgical correction of congenital entropion in related Boer goat kids using a combination Hotz‐Celsus and lateral eyelid wedge resection procedure
Authors: Donnelly Kevin S. , Pearce Jacqueline W. , Giuliano Elizabeth A. , Fry Pamela R. , Middleton John R.
Published: April 2014

Five related Boer goat kids (≤4 months of age) were presented to the University of Missouri, Veterinary Teaching Hospital (MU‐VMTH) with epiphora and blepharospasm of several weeks duration and commencing prior to 1 month of age in all animals. Clinical examination confirmed euryblepharon and entropion bilaterally in two females and one male and unilaterally in two female kids. Deep stromal corneal ulceration was present in two eyes, and corneal granulation tissue and fibrosis were present in half (5/10) the affected eyes. A combination Hotz‐Celsus and lateral eyelid wedge resection procedure was performed on all affected eyelids. Recheck examinations and long‐term follow‐up confirmed resolution of the entropion, preservation of normal eyelid conformation, and restoration of ocular comfort. Pedigree analysis ruled out sex‐linked and autosomal dominant inheritance patterns; a specific mode of inheritance could not be determined. The Boer goat breed may be at increased risk for the development of entropion. This cases series represents the first report of entropion in the caprine species.
A SURVEY OF VETERINARY RADIATION FACILITIES IN 2010
Authors: Farrelly John , McEntee Margaret C.
Published: May 2014

A survey of veterinary radiation therapy facilities in the United States, Canada, and Europe was done in 2010, using an online survey tool, to determine the type of equipment available, radiation protocols used, caseload, tumor types irradiated, as well as other details of the practice of veterinary radiation oncology. The results of this survey were compared to a similar survey performed in 2001. A total of 76 facilities were identified including 24 (32%) academic institutions and 52 (68%) private practice external beam radiation therapy facilities. The overall response rate was 51% (39/76 responded). Based on this survey, there is substantial variation among facilities in all aspects ranging from equipment and personnel to radiation protocols and caseloads. American College of Veterinary Radiology boarded radiation oncologists direct 90% of the radiation facilities, which was increased slightly compared to 2001. All facilities surveyed in 2010 had a linear accelerator. More facilities reported having electron capability (79%) compared to the 2001 survey. Eight facilities had a radiation oncology resident, and academic facilities were more likely to have residents. Patient caseload information was available from 28 sites (37% of radiation facilities), and based on the responses 1376 dogs and 352 cats were irradiated in 2010. The most frequently irradiated tumors were soft tissue sarcomas in dogs, and oral squamous cell carcinoma in cats.
Extraction of 2-Acetyl-1-Pyrroline (2AP) in Pandan Leaves (Pandanus Amaryllifolius Roxb.) Via Solvent Extraction Method: Effect of Solvent
Authors: Ngadi Norzita , Yahya Noor Yahida
Published: April 2014

Pandan (Pandanus amaryllifolius Roxb.) leaves are widely used in Malaysia as a source of natural flavoring.  The major compound contributing to the characteristic flavour of Pandan is 2-acetyl-1-pyrroline (2AP). As the consumer requirement for use of natural flavours, extraction of components from natural sources has been sought. In this study, solvent extraction of 2AP from Pandan leaves was performed. The effect of solvent used during extraction process (i.e. methanol, ethanol, propanol) towards the yield of 2AP was investigated. The presence of 2AP was determined using GCMS. The results obtained showed that ethanol was the best solvent to extract 2AP from Pandan leaves compared to methanol as higher 2AP peak arises from ethanol chromatogram.  However there is no 2AP detected when propanol was used as solvent.  It is believed that polarity of the solvent plays an important role in the extraction of 2AP.
Formulation of Green Varnish from Ecological Friendly Material for the Development of Offset Printing Ink
Authors: Idham Zuhaili , Che Yunus Mohd Azizi , Abdul Aziz Mustafa Kamal , Mohd Setapar Siti Hamidah , Mohamad Hasanah
Published: April 2014

The extensive use of petroleum product has caused a number of environmental pollution. The printing industry is one of our nation’s largest producers of hazardous waste and volatile organic compound. One of the major alternatives is to use vegetable oil based products as biorenewable raw materials. Hence, the formulation of palm olein based varnish has been discussed in the present study. Palm olein from palm oil was prepared first, and their physical properties were determined. Varnishes were prepared with the palm olein and four different types of resin (F-2136, F-210, F-2110 and F-2118). Rheological properties, yield value, heptanes tolerance of the varnish were determined. From this study, it was found that palm olein with the F-210 resin is promising as the alternative varnish materials for the production of offset printing ink.
Carrier Assisted Emulsion Liquid Membrane Process for Recovery of Basic Dye from Wastewater using Continuous Extractor
Authors: Othman Norasikin , Zing-Yi Ooi , Harruddin Norlisa , Norimie Raja , Jusoh Norela , Zailani Siti Nazrah
Published: April 2014

Nowadays, water pollution has become major issue especially dye contaminated wastewaters from the textile industry. Dye causes serious environmental pollution and health problems. The removal of color from dye-contaminated wastewaters in the related industries becomes a major concern all over the world. In this research, several parameters of dye extraction and recovery in the continuous emulsion liquid membrane (ELM) process were investigated. This process consisted of three phases which are external (feed) phase, membrane phase and internal phase. The membrane phase was prepared by dissolving extractant bis(2-ethylhexyl)phosphoric acid (D2EHPA) and hydrophobic surfactant sorbitan monooleate (Span 80) in kerosene as diluents. The internal phase consisted of an aqueous solution of sulfuric acid (H2SO4). The important parameters governing the extraction process of dye such as stirring speed, initial dye concentration, Span 80 concentration and treat ratio (volume ratio of emulsion to external phase) were studied. The results showed that the optimum condition for 25ppm initial concentration of dye extraction are 250 rpm stirring speed, 5% (w/v) Span 80 and treat ratio 1:5. At this condition, the percentage of dye extraction, stripping and recovery were 98%, 82% and 81% respectively. Hence, continuous ELM technique is proven to be a very promising technique in industrial wastewater treatment and recovery of dye.
Enzymatic Hydrolysis of Used-Frying Oil Using Candida Rugosa Lipase in Solvent-Free System
Authors: Rashid Roslina , Zaharudin Nor Athirah , Idris Ani
Published: April 2014

The effects of enzymatic hydrolysis of used-frying oil were carried out using an immobilized lipase from Candida rugosa in solvent-free system. Used-frying oil was used as a substrate in this study due to abundance amount of used-frying oil present in Malaysia as its disposal problem become a very serious environmental issue. The high free fatty acids (FFA) content in used-frying oil has raised the interest for the utilization of this waste into valuable products. Even though used-frying oil is not suitable for human consumption and being extensively used for biodiesel production, FFA from used-frying oil could be utilized to produce various types of non-edible products. Effects of enzyme loading, water content, reaction temperature, buffer pH and agitation speed on the degree of hydrolysis were investigated. The experiments were conducted at constant 3 hours reaction time. It was found that the effect of variables were very significant by influencing the hydrolysis process. The hydrolysis process achieved the highest yield of fatty acids at enzyme concentration of 1.5% (w/v), buffer volume to oil volume ratio of 3:1, temperature of 40 ˚C, pH of 7 and agitation speed of 220 rpm. Under these described conditions, nearly 98.1% degree of hydrolysis was achieved. A kinetic model based on Michaelis-Menten equation was used to determine the rate constant of Vmaxand Kmand it was found that the values are20.8333µmol/ml.min and0.0833g/ml respectively which were gained from Lineweaver-Burk plot.
PI Adaptive Neuro-Fuzzy and Receding Horizon Position Control for Intelligent Pneumatic Actuator
Authors: Hikmat Omer Faris , Mohd Faudzi Ahmad 'Athif , Elnimair Mohamed Omer , Osman Khairuddin
Published: April 2014

Pneumatic systems are widely used in automation industries and in the field of automatic control. Intelligent Pneumatic Actuators (IPA) is a new generation of actuators designed and developed for research and development (R&D) purposes. This work proposes two control approaches, Proportional Integral Adaptive Neuro-Fuzzy (PI-ANFIS) controller and Receding Horizon Controller (RHC), for IPA position control. The design steps of the controllers are presented. MATLAB/SIMULINK is used as a tool to implement the controllers. The design is based on a position identification model of the IPA. The simulation results are analyzed and compared with previous work on the IPA to illustrate the performance of the proposed controllers. The comparison shows a significant improvement in IPA position control after using the new controllers.
Thermogravimetric Analysis of the Fuel Properties of Empty Fruit Bunch Briquettes
Authors: Nyakuma Bemgba Bevan , Johari Anwar , Ahmad Arshad , Tuan Abdullah Tuan Amran
Published: April 2014

The thermochemical properties of biomass are largely influenced by the nature, yield and composition of the feedstock. In addition, the low moisture content, energy density and solid uniform structure of briquettes have been reported to improve heat and mass transfer during thermochemical conversion. Hence, this study is aimed at investigating the thermochemical properties of Empty Fruit Bunch (EFB) briquettes using Thermogravimetric analysis (TGA). The heating value (HHV), ultimate and proximate analysis was determined using standard ASTM techniques. Consequently, the thermal decomposition behavior of the fuel was determined by heating the sample from 50°C to 900°C in a thermogravimetric analyzer (TGA) at 10°C per min heating rate. The ultimate and proximate analysis revealed that EFB briquette contains low moisture content, ash content and high fixed carbon, volatile matter content while the HHV was 17.57 MJ/kg. In addition, TGA results indicated thermal decomposition of the fuel occurs in four stages. Devolatization commenced at 206°C with a peak devolatization temperature (Tmax) of 325°C resulting in 70% weight loss.
Progressive Freeze Concentration of Coconut Water: Effect of Circulation Flowrate and Circulation Time
Authors: Jusoh Mazura , Mohamed Nor Noor Naimah
Published: April 2014

Progressive freeze concentration integrated with a coil crystallizer was applied to concentrate coconut water in order to increase its sugar content. In progressive freeze concentration system, only a single ice is formed as a layer on cooled surface. It is introduced as an alternative in compensating the disadvantages of conventional method of freeze concentration, called suspension freeze concentration. In this research, the efficiency of the progressive freeze concentration system was determined through effective partition constant (K) value and percent increment of sugar content. Hence, the effect of circulation flowrate ranging from 2000 to 2800 ml/min and circulation time from 10 to 18 minutes on those two variables was then investigated through experiments designated using one factor at a time. From the experimental work, it was found that higher efficiency results at higher circulation flowrate of 2800 ml/min based on lower K and high percentage of sugar increment achieved. It was also found that the percentage of the sugar increment is high when the period given for circulating the solution is increased and the most suitable circulation time is 14 minutes.
Effect of Flowrate and Circulation Time on Fractionation of Refined Bleached and Deodorised Palm Oil using Progressive Freeze Concentration Method
Authors: Jusoh Mazura , Yahya Norshafika , Zakaria Zaki Yamani
Published: April 2014

This research concerns on the possibility of separating refined, bleached and deodorised palm oil (RBDPO) into olein and stearin using another alternative through Progressive Freeze Concentration (PFC) to replace the conventional process of dry fractionation. The process was carried out in stainless steel coil crystalliser and the quality of olein and stearin and the performance of crystalliser to purify the olein were analysed. The quality of oil was evaluated through iodine value (IV) and Slip Melting Point (SMP), while for the performance of PFC, effective partition constant, K, and yield of olein were used to determine the system efficiency. The purified olein were obtained for IV and SMP at higher flowrate (2800 mL/min) and longer period of time (60 min) are 55.87wijs and 23.04°C, 55.89wijs and 23.08°C, respectively. Meanwhile, the best K and yield of olein were obtained at higher flowrate and time, giving values of 0.2369, 67.99% and 0.238 and 67.93%, respectively.
Synthesis and Characterization of Green Porous Carbons with Large Surface Area by Two Step Chemical Activation with KOH
Authors: Nasri Noor Shawal , Jibril Mohammed , Ahmad Zaini Muhammad Abbas , Mohsin Rahmat , Dadum Hamza Usman , Musa Ahmed Murtala
Published: April 2014

Porous carbons were synthesized from coconut shell using chemical activation by potassium hydroxide (KOH). N2 adsorption isotherm analysis for BET surface area and pore volume of the synthesized porous carbon were carried out. The Langmuir surface area, BET surface area and pore volume are 1646 m2/g, 1353 m2/g and 0.6 cm3/g, respectively. From the FTIR analysis, hydroxyls, alkenes, carbonyls and aromatics functional groups were identified. The proximate and ultimate analysis shows high percentage of carbon and less ash content which indicates a good precursor material for porous carbon. The carbonization temperature and time were also varied to observe their effect on the yield of char, with carbonization at 7000C for 2 h having highest yield of 32%.
Optimization of Water Permeability of “Green” Non-Woven Filter Media from Lignocellulosic Fibers Using Taguchi Method
Authors: Sadikin A. N. , Nawawi M. G. M. , Othman N.
Published: April 2014

Water permeability is often used in characterization of the filter media. This paper focuses on the evaluating the effects of the process parameters and design parameters on the permeability of filter media as an output and considered as a response and the prediction of the optimal combination of synthesis parameters with an objective of maximizing the permeability. For this purpose, the Taguchi experimental design technique, analysis of varians (ANOVA), and signal-to noise (S/N) ratio were used. In this study, only eight filter configurations of Taguchi’s L8 orthogonal design were fabricated and tested. As a result from these experiments, the filter configuration satisfying the maximum water permeability value was determined, which show that statistical analysis is a useful method to quantify filter permeability objectively.
Decentralized Adaptive PI with Adaptive Interaction Algorithm of Wastewater Treatment Plant
Authors: Rahmat M. F. , Samsudin S. I. , Wahab N. A. , Che Razali Mashitah , Gaya Muhammad Sani
Published: April 2014

Wastewater treatment plant (WWTP) is highly known with the variation and uncertainty of the parameters, making them a challenge to be tuned and controlled. In this paper, an adaptive decentralized PI controller is developed for nonlinear activated sludge WWTP. The work is highlighted in auto-tuning the PI control parameters in satisfying straighten effluent quality and hence optimizing the nitrogen removal. The PI controller parameters are obtained by using simple updating algorithm developed based on adaptive interaction theory. The error function is minimized directly by approximate Frechet tuning algorithm without explicit estimation of the model. The effectiveness of the proposed controller is then validated by comparing the performance of activated sludge process to the benchmark PI under three different weather conditions with realistic variations in influent flow rate and composition. The algorithm is effectively applied in activated sludge system with improved dynamic performances in effluent quality index and energy consumed of Benchmark Simulation Model No.1.
ANFIS Modelling of Carbon and Nitrogen Removal in Domestic Wastewater Treatment Plant
Authors: Gaya Muhammad Sani , Abdul Wahab N. , Sam Y. M. , Samsudin Sahratul Izah
Published: April 2014

Wastewater treatment plant involves highly complex and uncertain processes, which are quite difficult to forecast. However, smooth and efficient operation of the treatment plant depends on an appropriate model capable of describing accurately the dynamic nature of the system. Most of the existing models were applied to industrial wastewater treatment plants. Therefore, this paper proposed an ANFIS model for carbon and nitrogen removal in the Bunus regional sewage wastewater treatment plant, Kuala Lumpur, Malaysia. For comparison, feed-forward neural network is used. Simulation results revealed that the ANFIS model demonstrated slightly better prediction capability in all the considered variables, chemical oxygen demand (COD), suspended solids (SS) and ammonium nitrogen (NH4-N) as compared to the FFNN model, thus proving that the proposed ANFIS model is reliable and useful to the wastewater treatment plant.
Highly uniform AlGaN/GaN HEMT films grown on 200-mm silicon substrates by plasma molecular beam epitaxy
Authors: Hoke William E. , Kennedy Theodore D. , Torabi Abbas , Lyman Peter S. , Howsare C. Alan , Schultz Brian D.
Published: May 2014

Highly uniform AlGaN/GaN HEMT films with good electron transport properties have been grown on 200-mm silicon substrates by plasma molecular beam epitaxy. X-ray diffraction measurements indicate an AlGaN compositional and thickness variation of ±1% across the wafer, and a 29 point resistance map of a HEMT yielded a sheet resistance of 451 Ω/sq ± 1.1%. The electron mobility for seven measurements taken across the diameter of the wafer was 1555 cm2/Vs ± 1%. The mobility obtained on 200-mm silicon is within 10% of the mobility obtained for GaN HEMTs grown on 100-mm SiC substrates, which have a much smaller lattice mismatch with GaN. The uniform films were obtained at GaN growth rates comparable to 100-mm growth and a chamber pressure well within the free molecular flow regime.
Cross-Country Skiing and Postexercise Heart-Rate Recovery
Authors: Mourot Laurent , Fabre Nicolas , Andersson Erik , Willis Sarah , Buchheit Martin , Holmberg Hans-Christer
Published: May 2014

Postexercise heart-rate (HR) recovery (HRR) indices have been associated with running and cycling endurance-exercise performance. The current study was designed (1) to test whether such a relationship also exists in the case of cross-country skiing (XCS) and (2) to determine whether the magnitude of any such relationship is related to the intensity of exercise before obtaining HRR indices. Ten elite male cross-country skiers (mean ± SD; 28.2 ± 5.4 y, 181 ± 8 cm, 77.9 ± 9.4 kg, 69.5 ± 4.3 mL · min−1 · kg−1 maximal oxygen uptake [VO2max]) performed 2 sessions of roller-skiing on a treadmill: a 2 × 3-km time trial and the same 6-km at an imposed submaximal speed followed by a final 800-m time trial. VO2 and HR were monitored continuously, while HRR and blood lactate (BLa) were assessed during 2 min immediately after each 6-km and the 800-m time trial. The 6-km time-trial time was largely negatively correlated with VO2max and BLa. On the contrary, there was no clear correlation between the 800-m time-trial time and VO2, HR, or BLa. In addition, in no case was any clear correlation between any of the HRR indices and performance time or VO2max observed. These findings confirm that XCS performance is largely correlated with VO2max and the ability to tolerate high levels of BLa; however, postexercise HRR showed no clear association with performance. The homogeneity of the group of athletes involved and the contribution of the arms and upper body to the exercise preceding determination of HRR may explain this absence of a relationship.
Modeling the Effect of a Prosthetic Limb on 4-km Pursuit Performance
Authors: Childers W. Lee , Gallagher Tim P. , Duncan J. Chad , Taylor Douglas K.
Published: May 2014

The individual pursuit is a 4-km cycling time trial performed on a velodrome. Parathletes with transtibial amputation (TTA) have lost physiological systems, but this may be offset by the reduced aerodynamic drag of the prosthesis. This research was performed to understand the effect of a unilateral TTA on Olympic 4-km pursuit performance. A forward-integration model of pursuit performance explored the interplay between power loss and aerodynamic gains in parathletes with TTA. The model is calibrated to a 4-km pursuit time of 4:10.5 (baseline), then adjusted to account for a TTA. Conditions simulated were based on typical pedal asymmetry in TTA (AMP), if foot stiffness were decreased (FLEX), if pedaling asymmetries were minimized (ASYM), if the prosthesis were aerodynamically optimized (AERO), if the prosthesis had a cosmetic cover (CC), and if all variables were optimized (OPT). A random Monte Carlo analysis was performed to understand model precision. Four-kilometer pursuit performances predicted by the model were 4:10.5, 4:20.4, 4:27.7, 4:09.2, 4:19.4, 4:27.9, and 4:08.2 for the baseline, AMP, FLEX, ASYM, AERO, CC, and OPT models, respectively. Model precision was ±3.7 s. While the modeled time decreased for ASYM and OPT modeled conditions, the time reduction fell within model precision and therefore was not significant. Practical application of these results suggests that parathletes with a TTA could improve performance by minimizing pedaling asymmetry and/or optimizing aerodynamic design, but, at best, they will have performance similar to that of intact cyclists. In conclusion, parathletes with TTA do not have a net advantage in the individual pursuit.
A Phenomenological Study of Obesity and Physical Activity in Southern African American Older Women
Authors: Bowen Pamela G. , Eaves Yvonne D. , Vance David E. , Moneyham Linda D.
Published: May 2014

African American women are more likely to be classified as overweight or obese than European American women and little is known about this phenomenon. The purpose of this qualitative study was to explore the lived experiences of overweight and obese African American older women living in the southern regions of the United States. Semistructured, audiotaped interviews were conducted to elicit narratives from nine participants. Interview data were transcribed verbatim and then coded and analyzed using Colaizzi’s phenomenological analysis framework. Three major categories emerged: impact of health conditions, incongruent perceptions, and the desire for independence. The focus of culturally appropriate interventions aimed at increasing physical activity for this group should incorporate activities that will help them remain independent, because weight loss is not a primary motivator.
An Acellular Biologic Scaffold Promotes Skeletal Muscle Formation in Mice and Humans with Volumetric Muscle Loss
Authors: Sicari Brian M. , Rubin J. Peter , Dearth Christopher L. , Wolf Matthew T. , Ambrosio Fabrisia , Boninger Michael , Turner Neill J. , Weber Douglas J. , Simpson Tyler W. , Wyse Aaron , Brown Elke H. P. , Dziki Jenna L. , Fisher Lee E. , Brown Spencer , Badylak Stephen F.
Published: April 2014

Scaffolds composed of cell-free extracellular matrix promote de novo formation of functional skeletal muscle tissue in sites of volumetric muscle loss.
Biobanks and Electronic Medical Records: Enabling Cost-Effective Research
Authors: Bowton Erica , Field Julie R. , Wang Sunny , Schildcrout Jonathan S. , Van Driest Sara L. , Delaney Jessica T. , Cowan James , Weeke Peter , Mosley Jonathan D. , Wells Quinn S. , Karnes Jason H. , Shaffer Christian , Peterson Josh F. , Denny Joshua C. , Roden Dan M. , Pulley Jill M.
Published: April 2014

Linking of data from electronic medical records to biological specimens enables cost-effective and rapid genomic analyses.
PGE2—The Immune System Tamer
Authors: Lemaire Mathieu
Published: April 2014

By chelating bioactive PGE2, a molecule with immunosuppressive properties, albumin helps preserve normal immune function.
Modification of the Ribosome and the Translational Machinery during Reduced Growth Due to Environmental Stress
Authors: Vila-Sanjurjo Antón
Published: May 2014

Escherichia coli
strains normally used under laboratory conditions have been selected for maximum growth rates and require maximum translation efficiency. Recent studies have shed light on the structural and functional changes undergone by the translational machinery in
E. coli
during heat and cold shock and upon entry into stationary phase. In these situations both the composition and the partitioning of this machinery into the different pools of cellular ribosomes are modified. As a result, the translational capacity of the cell is dramatically altered. This review provides a comprehensive account of these modifications, regardless of whether or not their underlying mechanisms and their effects on cellular physiology are known. Not only is the composition of the ribosome modified upon entry into stationary phase, but the modification of other components of the translational machinery, such as elongation factor Tu (EFTu) and tRNAs, has also been observed. Hibernation-promoting factor (HPF), paralog protein Y (PY), and ribosome modulation factor (RMF) may also be related to the general protection against environmental stress observed in stationary-phase
E. coli
cells, a role that would not be revealed necessarily by the viability assays. Even for the best-characterized ribosome-associated factors induced under stress (RMF, PY, and initiation factors), we are far from a complete understanding of their modes of action.
Ammonia Transport
Authors: Wingreen Ned S.
Published: May 2014

This review reviews the ammonium/methylammonium transport (Amt) proteins of
Escherichia coli
and
Salmonella enterica
serovar Typhimurium. The Amt proteins and their homologs, the methylammonium/ammonium permease proteins of
Saccharomyces cerevisiae
, constitute a distinct class of membrane-associated ammonia transporters. Members of the Amt family are found in archaea, bacteria, fungi, plants, and invertebrate animals. In
E. coli
and serovar Typhimurium, the Amt proteins are essential to maintain maximal growth at low concentrations of ammonia, the preferred nitrogen source. Soupene and coworkers showed that a mutant of
E. coli
with only the low-affinity glutamate dehydrogenase pathway for assimilation of ammonia, which therefore grows slowly at low ammonia concentrations, is not relieved of its growth defect by overexpression of AmtB. A recent study on an Amt protein from tomato concluded that it was a specific transporter for NH4
+
. A trimeric stoichiometry for AmtB is supported by the observation of a direct interaction between AmtB and the trimeric signal-transduction protein GlnK. In
E. coli
, GlnK has been observed to associate with the membrane in an AmtB-dependent fashion. Both GlnK and GlnB are sensors of nitrogen status. Their interaction with AmtB suggests a role for AmtB in nitrogen regulation. In summary, AmtB is a membrane-associated ammonia transporter that is important for growth at external concentrations of the uncharged species (NH
3
) below about 50 nM. The preponderance of evidence suggests that AmtB specifically transports the charged species (NH
4
+
) and that this transport is passive and, hence, bidirectional.
Catabolism of Amino Acids and Related Compounds
Authors: Reitzer Larry
Published: May 2014

This review considers the pathways for the degradation of amino acids and a few related compounds (agmatine, putrescine, ornithine, and aminobutyrate), along with their functions and regulation. Nitrogen limitation and an acidic environment are two physiological cues that regulate expression of several amino acid catabolic genes. The review considers
Escherichia coli
,
Salmonella enterica
serovar Typhimurium, and
Klebsiella
species. The latter is included because the pathways in
Klebsiella
species have often been thoroughly characterized and also because of interesting differences in pathway regulation. These organisms can essentially degrade all the protein amino acids, except for the three branched-chain amino acids.
E. coli
,
Salmonella enterica
serovar Typhimurium, and
Klebsiella aerogenes
can assimilate nitrogen from D- and L-alanine, arginine, asparagine, aspartate, glutamate, glutamine, glycine, proline, and D- and L-serine. There are species differences in the utilization of agmatine, citrulline, cysteine, histidine, the aromatic amino acids, and polyamines (putrescine and spermidine). Regardless of the pathway of glutamate synthesis, nitrogen source catabolism must generate ammonia for glutamine synthesis. Loss of glutamate synthase (glutamineoxoglutarate amidotransferase, or GOGAT) prevents utilization of many organic nitrogen sources. Mutations that create or increase a requirement for ammonia also prevent utilization of most organic nitrogen sources.
Biosynthesis of Arginine and Polyamines
Authors: Charlier Daniel , Glansdorff Nicolas
Published: May 2014

Early investigations on arginine biosynthesis brought to light basic features of metabolic regulation. The most significant advances of the last 10 to 15 years concern the arginine repressor, its structure and mode of action in both
E. coli
and
Salmonella typhimurium
, the sequence analysis of all
arg
structural genes in
E. coli
and
Salmonella typhimurium
, the resulting evolutionary inferences, and the dual regulation of the
carAB operon
. This review provides an overall picture of the pathways, their interconnections, the regulatory circuits involved, and the resulting interferences between arginine and polyamine biosynthesis. Carbamoylphosphate is a precursor common to arginine and the pyrimidines. In both
Escherichia coli
and
Salmonella enterica
serovar Typhimurium, it is produced by a single synthetase, carbamoylphosphate synthetase (CPSase), with glutamine as the physiological amino group donor. This situation contrasts with the existence of separate enzymes specific for arginine and pyrimidine biosynthesis in
Bacillus subtilis
and fungi. Polyamine biosynthesis has been particularly well studied in
E. coli
, and the cognate genes have been identified in the
Salmonella
genome as well, including those involved in transport functions. The review summarizes what is known about the enzymes involved in the arginine pathway of
E. coli
and
S. enterica
serovar Typhimurium; homologous genes were identified in both organisms, except
argF
(encoding a supplementary OTCase), which is lacking in
Salmonella
. Several examples of putative enzyme recruitment (homologous enzymes performing analogous functions) are also presented.
Type II Secretion in
Escherichia coli
Authors: Patrick Marcella , Gray Miranda D. , Sandkvist Maria , Johnson Tanya L.
Published: May 2014

The type II secretion system (T2SS) is used by
Escherichia coli
and other gram-negative bacteria to translocate many proteins, including toxins and proteases, across the outer membrane of the cell and into the extracellular space. Depending on the bacterial species, between 12 and 15 genes have been identified that make up a T2SS operon. T2SSs are widespread among gram-negative bacteria, and most
E. coli
appear to possess one or two complete T2SS operons. Once expressed, the multiple protein components that form the T2S system are localized in both the inner and outer membranes, where they assemble into an apparatus that spans the cell envelope. This apparatus supports the secretion of numerous virulence factors; and therefore secretion via this pathway is regarded in many organisms as a major virulence mechanism. Here, we review several of the known
E. coli
T2S substrates that have proven to be critical for the survival and pathogenicity of these bacteria. Recent structural and biochemical information is also reviewed that has improved our current understanding of how the T2S apparatus functions; also reviewed is the role that individual proteins play in this complex system.
DNA Helicases
Authors: Bianco Piero R.
Published: May 2014

DNA and RNA helicases are organized into six superfamilies of enzymes on the basis of sequence alignments, biochemical data, and available crystal structures. DNA helicases, members of which are found in each of the superfamilies, are an essential group of motor proteins that unwind DNA duplexes into their component single strands in a process that is coupled to the hydrolysis of nucleoside 5'-triphosphates. The purpose of this DNA unwinding is to provide nascent, single-stranded DNA (ssDNA) for the processes of DNA repair, replication, and recombination. Not surprisingly, DNA helicases share common biochemical properties that include the binding of single- and double-stranded DNA, nucleoside 5'-triphosphate binding and hydrolysis, and nucleoside 5'-triphosphate hydrolysis-coupled, polar unwinding of duplex DNA. These enzymes participate in every aspect of DNA metabolism due to the requirement for transient separation of small regions of the duplex genome into its component strands so that replication, recombination, and repair can occur. In
Escherichia coli
, there are currently twelve DNA helicases that perform a variety of tasks ranging from simple strand separation at the replication fork to more sophisticated processes in DNA repair and genetic recombination. In this chapter, the superfamily classification, role(s) in DNA metabolism, effects of mutations, biochemical analysis, oligomeric nature, and interacting partner proteins of each of the twelve DNA helicases are discussed.
Copper Homeostasis in
Escherichia coli
and Other
Enterobacteriaceae
Authors: Rensing Christopher , Franke Sylvia
Published: May 2014

An interesting model for studying environmental influences shaping microbial evolution is provided by a multitude of copper resistance and copper homeostasis determinants in enteric bacteria. This review describes these determinants and tries to relate their presence to the habitat of the respective organism, as a current hypothesis predicts that the environment should determine an organism’s genetic makeup. In
Escherichia coli
there are four regulons that are induced in the presence of copper. Two, the CueR and the CusR regulons, are described in detail. A central component regulating intracellular copper levels, present in all free-living enteric bacteria whose genomes have so far been sequenced, is a Cu(I)translocating P-type ATPase. The P-type ATPase superfamily is a ubiquitous group of proteins involved in the transport of charged substrates across biological membranes. Whereas some components involved in copper homeostasis can be found in both anaerobes and aerobes, multi-copper oxidases (MCOs) implicated in copper tolerance in
E. coli
, such as CueO and the plasmid-based PcoA, can be found only in aerobic organisms. Several features indicate that CueO, PcoA, and other related MCOs are specifically adapted to combat copper-mediated oxidative damage. In addition to these well-characterized resistance operons, there are numerous other genes that appear to be involved in copper binding and trafficking that have not been studied in great detail. SilE and its homologue PcoE, for example, are thought to effect the periplasmic binding and sequestration of silver and copper, respectively.
Magnesium Transport and Magnesium Homeostasis
Authors: Papp-Wallace Krisztina M. , Maguire Michael E.
Published: May 2014

This review reviews the properties and regulation of the
Salmonella enterica
serovar Typhimurium and
Escherichia coli
transporters that mediate Mg
2+
influx: CorA and the Mgt P-type ATPases. In addition, potential Mg
2+
regulation of transcription and translation, largely via the PhoPQ two component system, is discussed. CorA proteins are a unique class of transporters and are widespread in the
Bacteria
and
Archaea
, with rather distant but functional homologs in eukaryotes. The Mgt transporters are highly homologous to other P-type ATPases but are more closely related to the eukaryotic H
+
and Ca
2+
ATPases than to most prokaryotic ATPases. Hundreds of homologs of CorA are currently known from genomic sequencing. In contrast, only when extracellular and possibly intracellular Mg
2+
levels fall significantly is the expression of
mgtA
and
mgtB
induced. Topology studies using
blaM
and
lacZ
fusions initially indicated that the
Salmonella
serovar Typhimurium CorA contained three transmembrane (TM) segments; however, subsequent data obtained using a variety of approaches showed that the CorA superfamily of proteins have only two TMs at the extreme C terminus. PhoP-PhoQ is a two-component system consisting of PhoQ, the sensor/receptor histidine kinase, and PhoP, the response regulator/transcriptional activator. The expression of both
mgtA
and
mgtCB
in either
E. coli
or
Salmonella
serovar Typhimurium is markedly induced in a PhoPQ-dependent manner by low concentrations of Mg
2+
in the medium.
phoP
and
phoQ
form an operon with two promoters in both
E. coli
and
Salmonella
serovar Typhimurium.
Transition Metal Homeostasis
Authors: Nies Dietrich H. , Grass Gregor
Published: May 2014

This chapter focuses on transition metals. All transition metal cations are toxic—those that are essential for
Escherichia coli
and belong to the first transition period of the periodic system of the element and also the "toxic-only" metals with higher atomic numbers. Common themes are visible in the metabolism of these ions. First, there is transport. High-rate but low-affinity uptake systems provide a variety of cations and anions to the cells. Control of the respective systems seems to be mainly through regulation of transport activity (flux control), with control of gene expression playing only a minor role. If these systems do not provide sufficient amounts of a needed ion to the cell, genes for ATP-hydrolyzing high-affinity but low-rate uptake systems are induced, e.g., ABC transport systems or P-type ATPases. On the other hand, if the amount of an ion is in surplus, genes for efflux systems are induced. By combining different kinds of uptake and efflux systems with regulation at the levels of gene expression and transport activity, the concentration of a single ion in the cytoplasm and the composition of the cellular ion "bouquet" can be rapidly adjusted and carefully controlled. The toxicity threshold of an ion is defined by its ability to produce radicals (copper, iron, chromate), to bind to sulfide and thiol groups (copper, zinc, all cations of the second and third transition period), or to interfere with the metabolism of other ions. Iron poses an exceptional metabolic problem due its metabolic importance and the low solubility of Fe(III) compounds, combined with the ability to cause dangerous Fenton reactions. This dilemma for the cells led to the evolution of sophisticated multi-channel iron uptake and storage pathways to prevent the occurrence of unbound iron in the cytoplasm. Toxic metals like Cd
2+
bind to thiols and sulfide, preventing assembly of iron complexes and releasing the metal from iron-sulfur clusters. In the unique case of mercury, the cation can be reduced to the volatile metallic form. Interference of nickel and cobalt with iron is prevented by the low abundance of these metals in the cytoplasm and their sequestration by metal chaperones, in the case of nickel, or by B
12
and its derivatives, in the case of cobalt. The most dangerous metal, copper, catalyzes Fenton-like reactions, binds to thiol groups, and interferes with iron metabolism.
E. coli
solves this problem probably by preventing copper uptake, combined with rapid efflux if the metal happens to enter the cytoplasm.