bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Lawn Maintenance on Nutrient Losses Via Overland Flow During Natural Rainfall Events1
Authors: Spence Porchè L. , Osmond Deanna L. , Childres Wesley , Heitman Joshua L. , Robarge Wayne P.
Published: May 2012

Spence, Porchè L., Deanna L. Osmond, Wesley Childres, Joshua L. Heitman, and Wayne P. Robarge, 2012. Effects of Lawn Maintenance on Nutrient Losses Via Overland Flow During Natural Rainfall Events. Journal of the American Water Resources Association (JAWRA) 48(5): 909‐924. DOI: 10.1111/j.1752‐1688.2012.00658.x

Abstract:  A sampling system was used to evaluate the effect of residential lawn management on nutrient losses via overland flow generated during natural rainfall events from three residential landscapes: a high maintenance fescue lawn (HMFL), a low maintenance fescue lawn (LMFL), and a mixed forested residential landscape (FRL). A sampling system was located in designated areas within each landscape such that 100% of the runoff follows natural flow paths to the outlet ports and collects in sterile Nalgene® B3 media bags (Thermo Fisher Scientific, Rochester, NY). A rainfall event was defined as producing ≥2.54 mm of water. A total of 87 rainfall events occurred during a 20‐month monitoring period. The total runoff volume collected from the LMFL was higher than from the HMFL and FRL, but on average <1% of the total rainfall was collected from the three landscapes. Mean nitrate concentrations from each lawn did not exceed 0.6 mg N/l. Nutrient unit area losses from the HMFL, LMFL, and FRL were 1,000 times less than fertilizer and throughfall inputs, which were due to the presence of well‐structured soils (low bulk densities) with high infiltration rates. This study demonstrated that the frequency of runoff, total runoff volumes, and nutrient losses during natural rainfall events are lower from highly maintained (i.e., irrigation, fertilizer application, and reseeding) densely uniform manicured lawns than low maintenance lawns and forested residential landscapes.
LIPID‐LOWERING THERAPY IN CHRONIC KIDNEY DISEASE: IS THERE A ROLE FOR EZETIMIBE?
Authors: Green Darren , Panayotova Rosica , Ritchie James P. , O’Riordan Edmond , McDonald John
Published: May 2012

The use of lipid‐lowering therapy (LLT) in chronic kidney disease (CKD) results in a reduction in atherosclerotic cardiovascular events but not mortality. The risk reduction for patients on dialysis appears to be less than in pre‐dialysis CKD. These findings may be due to the higher rate of non‐atherosclerotic cardiovascular disease found in end‐stage disease. Because of this, the role of LLT is less clear in CKD than in the general population. This review outlines the results of recent trials of LLT, particularly Ezetimibe, and implications for patients with CKD.

The evidence in favour of lipid lowering in CKD comes largely from the SHARP study. This study used combined simvastatin and Ezetimibe to reduce cholesterol. Though the benefits of statins are well proven, there is no evidence that Ezetimibe independently reduces cardiovascular events in any population. Data which support the use of Ezetimibe show only that it effectively reduces cholesterol. Surrogate end‐point data are contentious. Some studies suggest benefit whilst others suggest off‐target effects that question the validity of Ezetimibe in the absence of quality cardiovascular outcome data.
Unstable Trochanteric Fractures in Elderly Osteoporotic Patients: Role of Primary Hemiarthroplasty
Authors: Karthik Karuppaiah , Natarajan Mayilvahanan
Published: May 2012

Objective

Unstable intertrochanteric fractures in osteoporotic patients are difficult to treat. Fixation failure often leads to prolonged morbidity and poor functional outcomes. The objective of the present study was to investigate primary replacement as a suitable option that could minimize complications in selected patients.

Methods

From January 2004 to March 2007, 28 elderly osteoporotic patients with unstable intertrochanteric fractures were included in this study. Their fractures were classified according to the AO/OTA classification (8 patients, 31A2.2; 17 patients, 31A2.3 and 3 patients, 31A3.3) and their osteoporosis was confirmed by bone densitometry. Hemiarthroplasty was performed in all patients and the outcomes analyzed using the Harris hip score system.

Results

Of the 28 patients, 19 were women and the mean age was 79 years (range, 52–95 years). At a mean follow up of 4.2 years (range, 3–6 years), there were 17 excellent, 7 good, 2 fair and 2 poor results according to the Harris hip score system.

Conclusion

In elderly osteoporotic patients with unstable intertrochanteric fractures, hemiarthroplasty is a reliable alternative to internal fixation. The functional outcome has been encouraging and we suggest it as a method of treatment in this group of patients.
Motion Analysis of Single‐Level Cervical Total Disc Arthroplasty: A Meta‐Analysis
Authors: Chen Jian , Fan Shun‐wu , Wang Xin‐wei , Yuan Wen
Published: May 2012

Objective

The purpose of this review was to investigate whether cervical total disc arthroplasty (CTDA) preserves motion of the treated level and what its effect is on adjacent segments.

Methods

Relevant published reports were collected from PubMed, Medline and Cochrane library. The original studies were considered eligible only if the range of motion (ROM) of the index or adjacent level had been investigated. A meta‐analysis was then performed on the collected data. Statistical heterogeneity across the various trials was tested using Cochran's Q statistic and I
2; in the case of heterogeneity, a random effect model was used.

Results

The weighted mean differences (WMDs) of the index level were 0.34 (95% confidence interval [CI], −0.53∼1.21, P = 0.440) and 0.23 (95% CI, −1.92∼2.38, P = 0.834) in all included studies and randomized control trials (RCTs), respectively. The WMDs of the cranial adjacent levels, caudal adjacent levels and whole cervical spines were 1.01 (95% CI, 0.55∼1.47, P = 0.000), 1.10 (95% CI, 0.61∼1.59, P = 0.000) and 3.40 (95% CI, −6.02∼12.82, P = 0.479), respectively.

Conclusion

These findings suggest that the protective effect against adjacent segment degeneration provided by cervical arthroplasty might not be as good as has been believed. Long‐term supporting evidence is still needed.
Artrhoscopic Rotator Cuff Repair with Augmentation: The V‐sled Technique
Authors: Chillemi Claudio , El Boustany Stefano , Dei Giudici Luca , Ippolito Giorgio
Published: May 2012

Numerous techniques have been described for patch positioning in rotator cuff shoulder arthroscopic surgery. These techniques seem to be difficult challenges for the majority of arthroscopic surgeons, and because of that they are called “highly demanding” techniques. Without the use of dedicated instruments and cannulas, the authors propose a V‐sled technique that seems to be more reproducible, quicker and less difficult to perform for arthroscopic shoulder surgeons. The patient is placed in the lateral position. All arthroscopic procedures are performed without the use of cannulas. The standard posterior portal is used for the glenohumeral (GH) joint arthroscopy with fluid inflowing through the scope. After an accurate evaluation of the GH space, the scope is then introduced into the subacromial space. With the use of a spinal needle, a lateral portal is performed. The great tuberosity is prepared with a bur to place two 5.5 mm triple‐loaded radiolucent anchors. In addition, two free high strength sutures are passed through the muscle, respectively. The repair is performed using two high strength sutures from each anchor. The third wire from each anchor is retrieved out of the accessories portals used for the insertion of the anchors. In addition, two free high strength sutures are passed through the muscle, and the patch sizing is done using a measuring probe introduced through the lateral portal. Next, the patch is then prepared and is introduced into the subacromial space, and then the patch is stabilized, and the free sutures are tied.
Medial Patellar Retinaculum Plasty Versus Medial Capsule Reefing for Patellar Subluxation in Adult
Authors: Ma Long‐fei , Wang Fei , Chen Bai‐cheng , Wang Cheng‐hai , Zhou Jian‐wei , Ji Gang , Dong Jiang‐tao
Published: May 2012

Objective

The purpose of this study was to evaluate the clinical and functional results of surgical treatment for patellar subluxation.

Methods

A retrospective study was undertaken between October 2004 and April 2009 of 78 cases of patellar subluxation: 40 cases with medial capsule reefing, of which 15 cases had the combination of lateral retinacular release (Group A); and 38 cases with medial patellar retinaculum plasty, of which 12 cases had the combination of lateral retinacular release (Group B). All patients had CT scans available for reviewing congruence angle (CA) with knee flexion at 30 degrees. In addition, knee function was evaluated using the Kujala score and subjective questionnaires.

Results

Patients were followed up for a mean 60 months (33–87 months). The Kujala score improved significantly from 78.3 ± 1.0 to 88.3 ± 1.6 in Group A and from 77.8 ± 0.9 to 91.2 ± 1.7 in Group B (P < 0.05). Postoperatively, the CA on CT scan had a statistical difference between the two groups (P < 0.05). The subjective questionnaire revealed a significant difference (P < 0.05), including 12 excellent, 20 good and eight fair in Group A, and 25 excellent, and 13 good in Group B.

Conclusion

The medial retinaculum plasty was better than medial capsule reefing in improving the subjective effects and decreasing the patellar subluxation rate.
Bone Delivers Its Energy Information to Fat and Islets Through Osteocalcin
Authors: Chen Xiang , Tian Hao‐ming , Yu Xi‐jie
Published: May 2012

Bone has emerged as a novel endocrine organ for its ability to produce hormones and involvement in several regulatory feedback loops. Osteocalcin (OCN) is released into bloodstream during bone resorption and has been demonstrated to exert endocrine regulation on islets, fat and male testis to form feedback loops. We hypothesize that bone delivers its energy metabolism signals to related energy‐regulating organs through OCN based on the following evidence: First, OCN has close interactions with islets and fat, and it shows ability to stimulate islets and fat to secret insulin and adiponectin, respectively. Islets and fat are important organs involved in energy metabolism. Second, OCN undergoes physiological fluctuations during a lifetime. In children and adolescents, during the development of osteoporosis or after bone fracture, OCN level increases significantly. The elevated OCN at these stages represents enhanced bone turnover and metabolic activity, which require more energy supply. Therefore, the metabolic activity of bone and the energy‐related organs like fat and islets are closely linked by circulating OCN. Through systemic release of OCN, bone delivers its energy‐demanding information to other organs to satisfy its energy requirement.
Rebalancing the Global Economy
Authors: Collignon Stefan
Published: May 2012

Imbalances are a dominant feature of the world economy and they are often seen as having contributed to the global financial crisis. A revaluation of the Chinese currency is often recommended to reduce the current account imbalance between the US and China. This article argues that emerging Asia’s current account surpluses are a necessary condition for rapid catch‐up growth and should not be eliminated soon; instead the excessive dollar bias in Asian holdings of external claims needs to be reduced, because the problem behind the recent crisis was that the emerging economies have placed their foreign exchange reserves almost exclusively in USD assets and have neglected alternative assets like the Euro and the Yen. A policy proposal for a common Asian peg to a basket of Euro and Yen is made.

Policy Implications

 Policies to restore global balances must not create additional tensions for China, Asia, Europe or the United States. A cooperative management of the global economy is recommended.

 Chinese exchange rates policy must be seen in the broad context of the Asian development model. A rapid revaluation or shift to flexible exchange rates would undermine the Chinese development model and deprive the world of an immense source of economic growth.

 The undervaluation of the RMB should only gradually be removed as the Chinese economy improves productivity and catches up to advanced economies’ production standards.

 Fixed exchange rates support economic development by reducing uncertainty for investment and trade. Stabilising the exchange rates between major currencies and Asia as a region is important to allow the continuing integration of its developing economies into the world market.

 The US economy needs flexibility in exchange rate movement while it is going through the necessary adjustment of its current account balance, but not Asia. Asia should peg to a basket of euro and yen and Chinese foreign exchange reserves should be marginally shifted into these new reserve currencies. Europe must not protect its industries, but rather seek to stimulate economic growth by inviting Chinese and Asian investment by developing its financial markets.
From the State to the Market and Back: Policy Implications of Changing Energy Paradigms
Authors: Goldthau Andreas
Published: May 2012

Like almost no other sector, energy reflects changing paradigms. Following a statist approach in which energy services were subject to public provision and administered by state companies, the free market paradigm took over in the 1980s and 1990s, making energy subject to private provision instead. More recently, the world has witnessed a new era of interventionism. Assessing these different phases, this article advances three arguments. First, paradigms matter in energy as they provide for crucial policy prescriptions. Second, agendas have become more complex, adding sustainability and energy poverty to traditional supply security. Third, paradigms are inextricably linked to rule‐setting power, putting the non‐OECD world in charge of defining the next paradigm. With regards to the latter, it is argued that it will likely be one characterised by fragmentation, with elements of state and market coexisting.
Generating Economic Growth – How Governments can Help Successfully
Authors: Klasen Andreas
Published: May 2012

This article points out challenges that have arisen in the current economic situation, discusses the success of export orientated and Small and Medium Enterprise (SME) dominated countries such as Germany, analyses companies’ specific financing needs, and examines how governments can successfully support growth in their economies without creating additional direct fiscal burdens.
Management of malignant pleural effusion: Options and recommended approaches
Authors: Leung Linda , Hsin Michael , Lam Kwok Chi
Published: May 2012

There is no consensus on the best management of symptomatic malignant pleural effusion. Drainage with a small bore pleural catheter is preferred over a wide bore catheter or recurrent pleural aspiration in patients with symptomatic malignant pleural effusion, for equivalent efficacy and patient comfort. If resources allow, chemical pleurodesis under thoracoscopy, with talc as sclerosant, is preferred for fully expanded lung over bedside chemical pleurodesis in fit patients. A chronic indwelling catheter is an alternative. Controversy exists over the use of chemical pleurodesis or a long term indwelling catheter as the first line management of choice of malignant pleural effusion. Pleural effusion in the entrapped lung scenario is a problematic situation. Pleuroperitoneal shunting or decortication procedures are out of favor as they are more invasive and present more complications. Management algorithm is recommended based on the current data.
Oral Histories in Meteoritics and Planetary Science – XV: John Wood
Authors: SEARS Derek W. G.
Published: May 2012

Abstract– John Wood (Fig. 1) was trained in Geology at Virginia Tech and M.I.T. To fulfill a minor subject requirement at M.I.T., he studied astronomy at Harvard, taking courses with Fred Whipple and others. Disappointed at how little was known in the 1950s about the origin of the earth, he seized an opportunity to study a set of thin sections of stony meteorites, on the understanding that these might shed light on the topic. This study became his Ph.D. thesis. He recognized that chondrites form a metamorphic sequence, and that idea proved surprisingly hard to sell. After brief service in the Army and a year at Cambridge University, John served for 3 years as a research associate with Ed Anders at the University of Chicago. He then returned to the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, where he spent the remainder of his career. At Chicago, he investigated the formation of the Widmanstätten structure, and found that the process informs us of the cooling rates of iron meteorites. Back in Cambridge, he collaborated with W. R. Van Schmus on a chondrite classification that incorporates metamorphic grade, and published on metal grains in chondrites, before becoming absorbed by preparations for the return of lunar samples by the Apollo astronauts. His group’s work on Apollo samples helped to establish the character of the lunar crust, and the need for a magma ocean to form it. Wood served as President of the Meteoritical Society in 1971–72 and received the Leonard Medal in 1978.

 John Wood.

image
Xenoliths and microxenoliths in H chondrites: Sampling the zodiacal cloud in the asteroid Main Belt
Authors: BRIANI Giacomo , GOUNELLE Matthieu , BOUROT‐DENISE Michèle , ZOLENSKY Michael E.
Published: May 2012

Abstract– Xenoliths are inclusions of a given meteorite group embedded in host meteorites of a different group. Xenoliths with dimensions between a few μm and about 1 mm (microxenoliths) are “meteorite‐trapped” analogues of micrometeorites collected on the Earth. However, they have the unique features of sampling the zodiacal cloud (1) at more ancient times than those sampled by micrometeorites and (2) at larger distances from the Sun (corresponding to the asteroid Main Belt) than that sampled by micrometeorites (1 AU). Herein we describe a systematic search for new xenoliths and microxenoliths in H chondrites, aimed at determining their abundance in these ordinary chondrites, analyzing their mineralogy, and searching for possible correlations with host meteorite properties. Sixty‐six sections from 40 meteorites have been analyzed. Twenty‐four new xenoliths have been discovered. About 87% of them are microxenoliths (i.e., <1 mm), only three are >1 mm in their largest dimension. All the newly discovered xenoliths and microxenoliths are composed of carbonaceous chondritic material. Hence, the zodiacal cloud was dominated by carbonaceous material even in past epochs. All the new xenoliths and microxenoliths have been found in regolith breccias. Hydrous‐phase‐rich xenoliths and microxenoliths in H4 and H5 chondrites attest that their embedding happened after the end of the thermal metamorphism. All these data suggest that xenoliths and microxenoliths were embedded when their host meteorites were part of the parent body regolith. This, combined with the H chondrite impact age distribution, attests that the embedding may have happened as early as 3.5 Gyr ago.
Battling the Demons of Complexity: Design Thinking in a Business Context
Authors: Mayfield Matt , Martinez Miguel , Pansard Catherine , Serr Rebecca , Shields Joe , Wong Sally
Published: May 2012

A packaged‐goods company joins forces with the ITT Institute of Design to explore how design methods can be used to help the operations side of its business.
Impact of pneumococcal microbial surface components recognizing adhesive matrix molecules on colonization
Authors: Voß S. , Gámez G. , Hammerschmidt S.
Published: May 2012

Microorganisms have evolved elaborate strategies to adhere to host cells and to evade the host complement and immune attack, ensuring survival in various host niches and dissemination into sterile parts of the human body. Streptococcus pneumoniae (the pneumococcus) is not only a commensal of the human respiratory tract but also the etiological agent of severe and life‐threatening diseases. Pneumococcal attachment to mucosal surfaces is a highly dynamic process requiring the contact of pneumococcal surface‐exposed proteins with soluble or immobilized host factors. These avid interactions may trigger proteolytic cascades or result in engagement of cell surface receptors and intracellularly associated signaling machineries for subsequent uptake of pneumococci into host cells. In the present review, the intimate communication of S. pneumoniae molecules recognizing adhesive matrix molecules (microbial surface components recognizing adhesive matrix molecules) with their host counterparts and their individual role in pneumococcal colonization is discussed.
Pneumococcal surface proteins: when the whole is greater than the sum of its parts
Authors: Pérez‐Dorado I. , Galan‐Bartual S. , Hermoso J.A.
Published: May 2012

Surface‐exposed proteins of pathogenic bacteria are considered as potential virulence factors through their direct contribution to host–pathogen interactions. Four families of surface proteins decorate the cell surface of the human pathogen Streptococcus pneumoniae. Besides lipoproteins and LPXTG proteins, also present in other gram‐positive bacteria, the pneumococcus presents the choline‐binding protein (CBP) family and the non‐classical surface proteins (NCSPs). The CBPs present specific structural features that allow their anchorage to the cell envelope through non‐covalent interaction with choline residues of lipoteichoic acid and teichoic acid. NCSP is an umbrella term for less characterized proteins displaying moonlighting functions on the pneumococcal surface that lack a leader peptide and membrane‐anchor motif. Considering the unceasing evolution of microbial species under the selective pressure of antibiotic use, detailed understanding of the interaction between pathogen and the host cells is required for the development of novel therapeutic strategies to combat pneumococcal infections. This article reviews recent progress in the investigation of the three‐dimensional structures of surface‐exposed pneumococcal proteins. The modular nature of some of them produces a great versatility and sophistication of the virulence functions that, in most cases, cannot be deduced by the structural analysis of the isolated modules.
Two GABAA responses with distinct kinetics in a sound localization circuit
Authors: Tang Zheng‐Quan , Lu Yong
Published: May 2012

Key points

It is known that synaptic inhibition plays important roles in auditory binaural neurons involved in sound localization.

Here, we show that GABAergic inhibition exhibits characteristic frequency (CF)‐dependent kinetics in auditory binaural neurons.

We further show that differential profiles of asynchronous release and spillover of GABA account for the distinct kinetics.

GABAergic inhibition regulates neuronal excitability in a CF‐dependent manner.

The results suggest that GABAergic inhibition may exert a dynamic modulation of sound localization processing in a CF‐dependent manner.

Abstract  The temporal characteristics and functional diversity of GABAergic inhibition are determined by the spatiotemporal neurotransmitter profile, intrinsic properties of GABAA receptors, and other factors. Here, we report two distinct GABAA responses and the underlying mechanisms in neurons of the chicken nucleus laminaris (NL), the first encoder of interaural time difference for sound localization in birds. The time course of the postsynaptic GABAA currents in NL neurons, recorded with whole‐cell voltage clamp, differed between different characteristic frequency (CF) regions. Compared to low‐CF (LF) neurons, middle/high‐CF (MF/HF) neurons had significantly slower IPSCs, with a 2.6‐fold difference in the decay time constants of spontaneous IPSCs and a 5.3‐fold difference in the decay of IPSCs elicited by single‐pulse stimulus. Such differences were especially dramatic when IPSCs were elicited by train stimulations at physiologically relevant frequencies, and at high stimulus intensities. To account for these distinct GABAA responses, we showed that MF/HF neurons exhibited more prominent asynchronous release of GABA. Supporting this observation, replacement of extracellular Ca2+ with Sr2+ increased the decay of IPSCs in LF neurons, and EGTA‐AM reduced the decay of IPSCs in MF/HF neurons. Furthermore, pharmacological evidence suggests that GABA spillover plays a greater role in prolonging the IPSCs of MF/HF neurons. Consequently, under whole‐cell current clamp, synaptically released GABA produced short‐ and long‐lasting suppression of the neuronal excitability of LF and MF/HF neurons, respectively. Taken together, these results suggest that the GABAergic inputs to NL neurons may exert a dynamic modulation of interaural time difference (ITD) coding in a CF‐dependent manner.
Plasticity of NMDA receptor‐mediated excitatory postsynaptic currents at perforant path inputs to dendrite‐targeting interneurons
Authors: Harney Sarah C. , Anwyl Roger
Published: May 2012

Key points

NMDA receptors (NMDARs) activated by the neurotransmitter glutamate underlie certain forms of synaptic plasticity in the brain.

These receptors are also subject to plasticity and we have previously described both long‐term potentiation (LTP) and long‐term depression (LTD) of NMDARs in the principal granule cells of the dentate gyrus region of hippocampus.

The functional significance of these changes in NMDARs on hippocampal network activity depends on whether this occurs only on principal, excitatory neurons or if it also occurs on inhibitory interneurons.

Here we demonstrate differences in NMDAR subtype expression and plasticity in dendrite‐targeting interneurons compared to granule cells.

Interneurons displayed LTD of NMDAR‐mediated synaptic transmission in response to perforant path activation and had a high threshold for induction of LTP of NMDAR‐mediated synaptic currents, suggesting that opposing forms of plasticity at inputs to interneurons and principal cells may act to regulate granule cell dendritic integration and processing.

Abstract  Synaptic plasticity of NMDA receptors (NMDARs) has been recently described in a number of brain regions and we have previously characterised LTP and LTD of glutamatergic NMDA receptor‐mediated EPSCs (NMDAR‐EPSCs) in granule cells of dentate gyrus. The functional significance of NMDAR plasticity at perforant path synapses on hippocampal network activity depends on whether this is a common feature of perforant path synapses on all postsynaptic target cells or if this plasticity occurs only at synapses on principal cells. We recorded NMDAR‐EPSCs at medial perforant path synapses on interneurons in dentate gyrus which had significantly slower decay kinetics compared to those recorded in granule cells. NMDAR pharmacology in interneurons was consistent with expression of both GluN2B‐ and GluN2D‐containing receptors. In contrast to previously described high frequency stimulation‐induced bidirectional plasticity of NMDAR‐EPSCs in granule cells, only LTD of NMDAR‐EPSCs was induced in interneurons in our standard experimental conditions. In interneurons, LTD of NMDAR‐EPSCs was associated with a loss of sensitivity to a GluN2D‐selective antagonist and was inhibited by the actin stabilising agent, jasplakinolide. While LTP of NMDAR‐EPSCs can be readily induced in granule cells, this form of plasticity was only observed in interneurons when extracellular calcium was increased above physiological concentrations during HFS or when PKC was directly activated by phorbol ester, suggesting that opposing forms of plasticity at inputs to interneurons and principal cells may act to regulate granule cell dendritic integration and processing.
Online Monitoring System for Stand-Alone Photovoltaic Applications—Analysis of System Performance From Monitored Data
Authors: Torres M. , Muñoz F. J. , Muñoz J. V. , Rus C.
Published: May 2012

The Guidelines for the Assessment of Photovoltaic Plants provided by the Joint Research Centre (JRC) and the International Standard IEC 61724 recommend procedures for the analysis of monitored data to asses the overall performance of photovoltaic (PV) systems. However, the latter do not provide a well adapted method for the analysis of stand-alone photovoltaic systems (SAPV) with charge regulators without maximum power point tracker (MPPT). In this way, the IDEA Research Group has developed a new method that improves the analysis performance of these kinds of systems. Moreover, it has been validated an expression that compromises simplicity and accuracy when estimating the array potential in this kind of systems. SAPV system monitoring and performance analysis from monitored data are of great interest to engineers both for detecting a system malfunction and for optimizing the design of future SAPV system. In this way, this paper introduces an online monitoring system in real time for SAPV applications where the monitored data are processed in order to provide an analysis of system performance. The latter, together with the monitored data, are displayed on a graphical user interface using a virtual instrument (VI) developed in LABVIEW®. Furthermore, the collected and monitored data can be shown in a website where an external user can see the daily evolution of all monitored and derived parameters. At present, three different SAPV systems, installed in the Polytechnic School of University of Jaén, are being monitorized and the collected data are being published online in real time. Moreover, a performance analysis of these stand-alone photovoltaic systems considering both IEC 61724 and the IDEA Method is also offered. These three systems use the charge regulators more widespread in the market. Systems #1 and #2 use pulse width modulation (PWM) charge regulators, (a series and a shunt regulator, respectively), meanwhile System #3 has a charge regulator with MPPT. This website provides a tool that can be used not only for educational purposes in order to illustrate the operation of this kind of systems but it can also show the scientific and engineering community the main features of the system performance analysis methods mentioned above. Furthermore, it allows an external user to download the monitored and analysis data to make its own offline analysis. These files comply with the format proposed in the standard IEC 61724. The SAPV system monitoring website is now available for public viewing on the University of Jaén. (http://voltio.ujaen.es/sfa/index.html).
Discussion: “Slip-Flow Pressure Drop in Microchannels of General Cross Section”
Authors: Wang C. Y.
Published: May 2012

Partial slip occurs in a variety of important fluid flow situations. Recently several sources used the constant boundary slip assumption for the flow in a tube. By comparing with the exact solution for the slip flow in a triangular duct, we show the constant slip assumption invokes substantial errors in both local and global fluid dynamic properties.
Two-Phase Heat Transfer and Bubble Characteristics in a Microchannel Array
Authors: Lagus T. P. , Kulacki F. A.
Published: May 2012

Heat transfer coefficients and bubble motion characteristics are reported for two-phase water flow in an array of 13 equally spaced microchannels over an area of 1 cm2. Each channel has Dh = 451 ± 38 μm, W/H = 0.8, and L/Dh = 22.2. Uniform heat flux is applied through the base, and wall temperatures are determined from the thermocouple readings corrected for heat conduction effects. The upper surface is insulated and transparent. Single-phase heat transfer coefficients are in a good agreement with comparable trends of existing correlations for developing flow and heat transfer, although a difference is seen due to the insulated upper surface. Two-phase heat transfer coefficients and flow characteristics are determined for 221 < G < 466 kg/m2s and 250 < q < 1780 kW/m2. Heat transfer coefficients normalized with mass flux exhibit a trend comparable to that of available studies that use similar thermal boundary conditions. Flow visualization shows expanding vapor slug flow as the primary flow regime with nucleation and bubbly flow as the precursors. Analysis of bubble dynamics reveals ∼t1/3 dependence for bubble growth. Flow reversal is observed and quantified, and different speeds of the vapor phase fronts are quantified at the leading and trailing edges of vapor slugs once the bubble diameter equals the channel width. Bubble formation, growth, coalescence, and detachment at the outlet of the array are best characterized by the Weber number.
Optimum Nusselt Number for Simultaneously Developing Internal Flow Under Conjugate Conditions in a Square Microchannel
Authors: Moharana Manoj Kumar , Singh Piyush Kumar , Khandekar Sameer
Published: May 2012

A numerical study has been carried out to understand and highlight the effects of axial wall conduction in a conjugate heat transfer situation involving simultaneously developing laminar flow and heat transfer in a square microchannel with constant flux boundary condition imposed on bottom of the substrate wall. All the remaining walls of the substrate exposed to the surroundings are kept adiabatic. Simulations have been carried out for a wide range of substrate wall to fluid conductivity ratio (ksf ∼ 0.17–703), substrate thickness to channel depth (δsf ∼ 1–24), and flow rate (Re ∼ 100–1000). These parametric variations cover the typical range of applications encountered in microfluids/microscale heat transfer domains. The results show that the conductivity ratio, ksf is the key factor in affecting the extent of axial conduction on the heat transport characteristics at the fluid–solid interface. Higher ksf leads to severe axial back conduction, thus decreasing the average Nusselt number (Nu¯). Very low ksf leads to a situation which is qualitatively similar to the case of zero-thickness substrate with constant heat flux applied to only one side, all the three remaining sides being kept adiabatic; this again leads to lower the average Nusselt number (Nu¯). Between these two asymptotic limits of ksf, it is shown that, all other parameters remaining the same (δsf and Re), there exists an optimum value of ksf which maximizes the average Nusselt number (Nu¯). Such a phenomenon also exists for the case of circular microtubes.
A Reduced-Boundary-Function Method for Convective Heat Transfer With Axial Heat Conduction and Viscous Dissipation
Authors: Xu Zhijie
Published: May 2012

We introduce a new method of solution for the convective heat transfer under forced laminar flow that is confined by two parallel plates with a distance of 2a or by a circular tube with a radius of a. The advection–conduction equation is first mapped onto the boundary. The original problem of solving the unknown field T(x,r,t) is reduced to seek the solutions of T at the boundary (r = a or r = 0, r is the distance from the centerline shown in Fig. 1), i.e., the boundary functions Ta(x,t)≡T(x,r=a,t) and/or T0(x,t)≡T(x,r=0,t). In this manner, the original problem is significantly simplified by reducing the problem dimensionality from 3 to 2. The unknown field T(x,r,t) can be eventually solved in terms of these boundary functions. The method is applied to the convective heat transfer with uniform wall temperature boundary condition and with heat exchange between flowing fluids and its surroundings that is relevant to the geothermal applications. Analytical solutions are presented and validated for the steady-state problem using the proposed method.
A Compressible Permeation Approach to Elastomeric Space Seal Characterization
Authors: Garafolo Nicholas G. , Daniels Christopher C.
Published: May 2012

The development of elastomeric face seals is imperative for NASA’s manned space flight program. Lacking in the development of state-of-the-art space seals was a technique for predicting the performance of candidate designs prior to experimental characterization. To this end, a physics-based model for compressible permeation in elastomeric face seals was developed to provide a predictive methodology for designers and researchers. In this novel approach for seal research, compressibility effects and the dependence of permeability on pressure was retained. Two independent permeation parameters arose from an exact, analytical solution to the one-dimensional permeation transport equations. The application of the derived transport equations and the developed permeability coefficients resulted in a noteworthy and practical tool for seal researchers to predict the leak rate of alternative geometries. For an example in the methodology, the characterization of a candidate space seal material, silicone elastomer S0383-70, was performed. Results illustrated the model’s capability for capturing the permeation leak rate of elastomeric seals for various pressure differentials.
A Robust Solution of the Spatial Burmester Problem
Authors: Bai Shaoping , Angeles Jorge
Published: May 2012

The spatial Burmester problem is studied in this work, focusing on the synthesis of CCCC and RCCC linkages for rigid-body guidance, where R stands for revolute, C for cylindrical pair. The synthesis equations for CC and RC dyads are formulated using dual algebra. The formulation is developed in such a way that it leads to a robust solution, based on a semigraphical approach, which produces all the real solutions to the problem of CC-dyad synthesis for five given poses. This eases the equation-solving process by filtering out the complex solutions, while allowing for the handling of the special cases of none or infinitely many solutions. The synthesis procedure is illustrated with examples for four and five given poses.
Effect of Ground Arrangements on Swirling Flow in a Rectangular Duct Subjected to Electrohydrodynamic Effects
Authors: Saneewong Na Ayuttaya Suwimon , Chaktranond Chainarong , Rattanadecho Phadungsak , Kreewatcharin Thatchapong
Published: May 2012

This study presents a numerical analysis of electric fields distribution, characteristics of swirling flow and effect of inlet velocity (u0) from two ground arrangements, i.e., wire-to-wire (WW) and wire-to-plate (WP) in a rectangular duct subjected to electrohydrodynamic. In both arrangements, location of an electrode wire, which is suspended from the upper wall of the duct, is initially located at the centerline of the rectangular duct, and ground is fixed on the bottom wall. In WW, position of electrode is varied in the vertical direction, while in WP, they are varied both in the vertical and horizontal directions. Electrical voltage of 20 kV is applied and inlet velocity in range of 0.3 – 1 m/s is selected. The numerical results show that electric fields distributions from both arrangements are quite different. These results cause the characteristics of swirling flows to appear differently. In both arrangements the maximum electric fields intensity are not different for each identical gap value. When the gap is closer, electric fields increase significantly. When inlet velocity of air is increased, the strength of swirling flow is decreased because inertial force is superior to the electric body force.
In situ thickness and temperature measurements of CdTe grown by molecular beam epitaxy on GaAs substrate
Authors: Gu Renjie , Shen Chuan , Guo Yuying , Wang Weiqiang , Fu Xiangliang , Chen Lu
Published: May 2012

An in situ technique based on diffuse reflectance spectroscopy to measure the thickness and temperature of CdTe films grown by molecular beam epitaxy on GaAs substrates is studied in this paper. A new model considering the interference of a thin film is set up to correct the previous errors observed in temperature measurements. A precise thickness parameter can be acquired by fitting the curves of the diffuse reflectance spectrum. This correction procedure is verified at the growth temperature of CdTe, which shows a nonoscillation result of the band edge thermometry. Compared with the thickness measured by an ex situ IR transmission spectrum, the thickness determined by using this model has an accuracy of less than 0.01 μm. This measurement can be used for precise in situ noncontact precise monitoring of growth temperature and thickness.
Segmentation of ultrasonic breast tumors based on homogeneous patch
Authors: Gao Liang , Yang Wei , Liao Zhiwu , Liu Xiaoyun , Feng Qianjin , Chen Wufan
Published: May 2012

Purpose:

Accurately segmenting breast tumors in ultrasound (US) images is a difficult problem due to their specular nature and appearance of sonographic tumors. The current paper presents a variant of the normalized cut (NCut) algorithm based on homogeneous patches (HP‐NCut) for the segmentation of ultrasonic breast tumors.

Methods:

A novel boundary‐detection function is defined by combining texture and intensity information to find the fuzzy boundaries in US images. Subsequently, based on the precalculated boundary map, an adaptive neighborhood according to image location referred to as a homogeneous patch (HP) is proposed. HPs are guaranteed to spread within the same tissue region; thus, the statistics of primary features within the HPs is more reliable in distinguishing the different tissues and benefits subsequent segmentation. Finally, the fuzzy distribution of textons within HPs is used as final image features, and the segmentation is obtained using the NCut framework.

Results:

The HP‐NCut algorithm was evaluated on a large dataset of 100 breast US images (50 benign and 50 malignant). The mean Hausdorff distance measure, the mean minimum Euclidean distance measure and similarity measure achieved 7.1 pixels, 1.58 pixels, and 86.67%, respectively, for benign tumors while those achieved 10.57 pixels, 1.98 pixels, and 84.41%, respectively, for malignant tumors.

Conclusions:

The HP‐NCut algorithm provided the improvement in accuracy and robustness compared with state‐of‐the‐art methods. A conclusion that the HP‐NCut algorithm is suitable for ultrasonic tumor segmentation problems can be drawn.
Structure of the First Sphingosine 1-Phosphate Receptor
Authors: Parrill Abby L. , Lima Santiago , Spiegel Sarah
Published: May 2012

The lipid sphingosine 1-phosphate may laterally diffuse through the membrane to bind a receptor.
Science Signaling
Podcast: 22 May 2012
Authors: Shinohara Mari L. , VanHook Annalisa M.
Published: May 2012

Interferon-β therapy is only effective in treating a mouse model of multiple sclerosis when the disease is dependent upon the NLRP3 inflammasome.
An Aspirin a Day?
Authors: Ray L. Bryan
Published: May 2012

A possible molecular mechanism of action for a metabolite of aspirin is described.
Calpains Cleave and Activate TRPC5
Authors: Gough Nancy R.
Published: May 2012

Cleavage and activation of the cation channel TRPC5 by calpains may contribute to growth cone collapse.
Keeping Neutrophils On Track
Authors: Foley John F.
Published: May 2012

Neutrophils following a gradient of primary chemoattractant secrete leukotriene B
4
, generating a secondary gradient that enhances migration.
A Gatekeeper of Viral Entry
Authors: Andrianantoandro Ernesto
Published: May 2012

The receptor EphrinA2 promotes herpesvirus entry into endothelial cells.
Fat Remodeler
Authors: Wong Wei
Published: May 2012

Fibroblast growth factor 1A enables remodeling of adipose tissue in response to changes in diet.
In Vitro
Combination of Anidulafungin and Voriconazole against Intrinsically Azole-Susceptible and -Resistant Aspergillus spp
Authors: Planche Virginie , Ducroz Sebastien , Alanio Alexandre , Bougnoux Marie-Elisabeth , Lortholary Olivier , Dannaoui Eric
Published: May 2012

In vitro
interaction of anidulafungin with voriconazole was tested by a microdilution broth checkerboard technique and an agar diffusion method against 30
Aspergillus
clinical isolates belonging to five different species. By using a complete inhibition endpoint, indifferent interactions were observed for 97% of the isolates by the checkerboard technique (FIC index from 0.5 to 2) and for 100% of the isolates by the agar diffusion method (variation of −2 to +1 log
2
dilutions).
Extended Protection against Phlebovirus Infection Conferred by Recombinant Adenovirus Expressing Consensus Interferon (DEF201)
Authors: Gowen Brian B. , Ennis Jane , Sefing Eric J. , Wong Min-Hui , Jung Kie-Hoon , Turner Jeffrey D.
Published: May 2012

Punta Toro virus (PTV;
Bunyaviridae
,
Phlebovirus
) is related to Rift Valley fever virus (RVFV), a pathogenic agent which causes severe disease in humans and livestock primarily in the sub-Saharan region of Africa. The recent range expansion of RVFV and the potential for its intentional release into naïve populations pose a significant threat to public health and agriculture. Studies modeling disease in rodents and nonhuman primates have shown that PTV and RVFV are highly sensitive to the antiviral effects of alpha interferon (IFN-α), an important component of the innate antiviral host response. While recombinant IFN-α has high therapeutic value, its utility for the treatment of neglected tropical diseases is hindered by its short
in vivo
half-life and costly production of longer-lasting pegylated IFNs. Here, we demonstrate extended preexposure protection against lethal PTV challenge following a single intranasal administration of DEF201, which is a replication-deficient human adenovirus type 5 vector engineered to constitutively express consensus IFN-α (cIFN-α) from transduced host cells. DEF201 was also efficacious when administered within 24 h as a postexposure countermeasure. Serum concentrations of cIFN-α could be detected as early as 8 h following treatment and persisted for more than 1 week. The prolonged antiphlebovirus prophylactic effect, low production costs, and ease of administration make DEF201 a promising agent for intervention during natural disease outbreaks and for countering possible bioterrorist acts.
Maraviroc and Other HIV-1 Entry Inhibitors Exhibit a Class-Specific Redistribution Effect That Results in Increased Extracellular Viral Load
Authors: Kramer Victor G. , Schader Susan M. , Oliveira Maureen , Colby-Germinario Susan P. , Donahue Daniel A. , Singhroy Diane N. , Tressler Randy , Sloan Richard D. , Wainberg Mark A.
Published: May 2012

HIV entry inhibitors, such as maraviroc (MVC), prevent cell-free viruses from entering the cells. In clinical trials, patients who were treated with MVC often displayed viral loads that were above the limit of conventional viral load detection compared to efavirenz-based regimens. We hypothesize that viruses blocked by entry inhibitors may be redistributed to plasma, where they artificially increase viral load measurements compared to those with the use of antiretroviral drugs (ARVs) that act intracellularly. We infected PM-1 cells with CCR5-tropic HIV-1 BaL or CXCR4-tropic HIV-1 NL4-3 in the presence of inhibitory concentrations of efavirenz, raltegravir, enfuvirtide, maraviroc, and AMD3100, the latter three being entry inhibitors. Supernatant viral load, reverse transcriptase enzyme activity, and intracellular nucleic acid levels were measured at times up to 24 h postinfection. Infectivity of redistributed dual-tropic HIV-1 was assessed using TZM-bl cells. Extracellular viral load analysis revealed that entry inhibitor-treated cells had higher levels of virus in the supernatant than the cells treated with other ARVs at 8 h postinfection. By 24 h, the supernatant viral load was still higher for entry inhibitors than other ARVs. We observed a correlation between viral load and the step of entry inhibition. Dual-tropic virus infectivity was undiminished utilizing the CCR5 coreceptor following redistribution by CXCR4 entry inhibition. This
in vitro
model indicates that entry inhibitors exhibit a redistribution effect unseen with intracellular ARV drugs. Based on these results, the effectiveness of some entry inhibitors may be underestimated if plasma viral load is used as a sole indicator of clinical success.