bluuebunny/crossref_metadata_2025 huggingface dataset:
Radical Thiol–XClick Chemistry
Authors: Brummelhuis Niels ten , Schlaad Helmut
Published: March 2012

Radical thiol–ene and thiol–yne chemistry, that is, the free‐radical addition of thiols to unsaturated carbon–carbon bonds, has over the last decade developed into a powerful tool in the synthesis of numerous different materials, not in the least since this chemistry can possess the characteristics of a “click” reaction but because it is modular, achieves high yields in a short time, is selective toward a single product, and products are easy to purify. These characteristics are of great advantage in organic chemistry as, for instance, shown for the synthesis of bioactive molecules (glycoclusters and glycopeptides) and dendrimers, but also for the synthesis and modification of macromolecules, by step‐growth polymerization of multifunctional enes and thiols, respectively, and the addition of thiols to macromolecules bearing unsaturated groups (or vice versa). Another upcoming application is the modification of nanoparticles and surfaces, for which free‐radical thiol addition is supremely suitable because of its high yields and especially by the ease with which patterning of surfaces can be performed by using photochemical generation of free radicals.
Who is stressed? Comparing cortisol levels between individuals
Authors: Nepomnaschy Pablo A. , Lee Terry C.K. , Zeng Leilei , Dean C.B.
Published: March 2012

Cortisol is the most commonly used biomarker to compare physiological stress between individuals. Its use, however, is frequently inappropriate. Basal cortisol production varies markedly between individuals. Yet, in naturalistic studies that variation is often ignored, potentially leading to important biases.

Objectives:

Identify appropriate analytical tools to compare cortisol across individuals and outline simple simulation procedures for determining the number of measurements required to apply those methods.

Methods:

We evaluate and compare three alternative methods (raw values, Z‐scores, and sample percentiles) to rank individuals according to their cortisol levels. We apply each of these methods to first morning urinary cortisol data collected thrice weekly from 14 cycling Mayan Kaqchiquel women. We also outline a simple simulation to estimate appropriate sample sizes.

Results:

Cortisol values varied substantially across women (ranges: means: 1.9–2.7; medians: 1.9–2.8; SD: 0.26–0.49) as did their individual distributions. Cortisol values within women were uncorrelated. The accuracy of the rankings obtained using the Z‐scores and sample percentiles was similar, and both were superior to those obtained using the cross‐sectional cortisol values. Given the interindividual variation observed in our population, 10–15 cortisol measurements per participant provide an acceptable degree of accuracy for across‐women comparisons.

Conclusions:

The use of single raw cortisol values is inadequate to compare physiological stress levels across individuals. If the distributions of individuals' cortisol values are approximately normal, then the standardized ranking method is most appropriate; otherwise, the sample percentile method is advised. These methods may be applied to compare stress levels across individuals in other populations and species. Am. J. Hum. Biol. 2012. © 2012 Wiley Periodicals, Inc.
Design of a Fixed‐Order RST Controller for Interval Systems: Application to the Control of Piezoelectric Actuators
Authors: Khadraoui Sofiane , Rakotondrabe Micky , Lutz Philippe
Published: March 2012

This paper presents a technique for designing a robust polynomial RST controller for parametric uncertain systems. The uncertain parameters are assumed to be bounded by intervals. The computation of the controller is addressed by introducing the interval arithmetic. The controller synthesis is formulated as a set inversion problem that can be solved using the SIVIA algorithm. The proposed method is afterwards applied to design a robust controller for a piezoelectric microactuator. The experimental results show the efficiency of the proposed method. Finally, a fine stability analysis is performed to analytically prove the robustness of the designed controller.
Recognition of Problem Drinking among Young Adult Prisoners
Authors: Plant Gemma , Taylor Pamela J.
Published: March 2012

Alcohol is a preventable cause of illness, offending and other adversities worldwide. Prisoners are especially vulnerable. The aim of this study was to test the hypotheses that younger adult male prisoners are more likely to be hazardous drinkers than their older peers, but less likely to recognize this. The study cohort comprised 100 male prisoners aged 18–20 years and 157 aged 21 and over, who were interviewed and completed standard alcohol and drug questionnaires just after reception into prison. It was found that younger men were significantly more likely to be hazardous drinkers than their older peers but less likely to recognise this, even at scores on the Alcohol Use Disorders Identification Test (AUDIT) indicating dependency. They were also less likely to experience withdrawal symptoms, the main factor associated with problem drinking recognition at any age. Younger prisoners were less likely to be depressed, more likely to rate their social support as good and less likely to be dependent drug users. We conclude that reliance on younger prisoners to recognise their hazardous drinking would identify about one‐fifth of them. With a lower likelihood of withdrawal symptoms than older men, they are probably still metabolizing alcohol more effectively. Given their similarities to older prisoners in terms of any previous imprisonment and likely personality disorder, formal screening for hazardous drinking might prevent decline into problem drug use, depression, reoffending, re‐imprisonment, and social disconnection. Copyright © 2012 John Wiley & Sons, Ltd.
Ethynyl Benziodoxolones for the Direct Alkynylation of Heterocycles: Structural Requirement, Improved Procedure for Pyrroles, and Insights into the Mechanism
Authors: Brand Jonathan P. , Chevalley Clara , Scopelliti Rosario , Waser Jérôme
Published: March 2012

This report describes a full study of the gold‐catalyzed direct alkynylation of indoles, pyrroles, and thiophenes using alkynyl hypervalent iodine reagents, especially the study of the structural requirements of alkynyl benziodoxolones for an efficient acetylene transfer to heterocycles. An improved procedure for the alkynylation of pyrroles using pyridine as additive is also reported. Nineteen alkynyl benziodoxol(on)es were synthesized and evaluated in the direct alkynylation of indoles and/or thiophenes. Bulky silyl groups as acetylene substituents were optimal. Nevertheless, transfer of aromatic acetylenes to thiophene was achieved for the first time. An accelerating effect of a methyl substituent in both the 3‐ and 6‐position of triisopropylsilylethynyl‐1,2‐benziodoxol‐3(1H)‐one (TIPS‐EBX) on the reaction rate was observed. Competitive experiments between substrates of different nucleophilicity, deuterium labeling experiments, as well as the regioselectivity observed are all in agreement with electrophilic aromatic substitution. Gold(III) 2‐pyridinecarboxylate dichloride was also an efficient catalyst for the reaction. Investigations indicated that gold(III) could be eventually reduced to gold(I) during the process. As a result of these investigations, a π activation or an oxidative mechanism are most probable for the alkynylation reaction.
The Importance of the trans‐Enamine Intermediate as a β‐Lactamase Inhibition Strategy Probed in Inhibitor‐Resistant SHV β‐Lactamase Variants
Authors: Ke Wei , Rodkey Elizabeth A. , Sampson Jared M. , Skalweit Marion J. , Sheri Anjaneyulu , Pagadala Sundar Ram Reddy , Nottingham Michael D. , Buynak John D. , Bonomo Robert A. , van den Akker Focco
Published: March 2012

The ability of bacteria to express inhibitor‐resistant (IR) β‐lactamases is stimulating the development of novel inhibitors of these enzymes. The 2′β‐glutaroxypenicillinate sulfone, SA2‐13, was previously designed to enhance the stabilization of the deacylation‐refractory, trans‐enamine inhibitory intermediate. To test whether this mode of inhibition can overcome different IR mutations, we determined the binding mode of SA2‐13 through X‐ray crystallography, obtaining co‐crystals of the inhibitor–protein complex by soaking crystals of the IR sulfhydryl variable (SHV) β‐lactamase variants S130G and M69V with the inhibitor. The 1.45 Å crystal structure of the S130G SHV:SA2‐13 complex reveals that SA2‐13 is still able to form the stable trans‐enamine intermediate similar to the wild‐type complex structure, yet with its carboxyl linker shifted deeper into the active site in the space vacated by the S130G mutation. In contrast, data from crystals of the M69V SHV:SA2‐13 complex at 1.3 Å did not reveal clear inhibitor density indicating that this IR variant disfavors the trans‐enamine conformation, likely due to a subtle shift in A237.
Adherence to surveillance care guidelines after breast and colorectal cancer treatment with curative intent
Authors: Salloum Ramzi G. , Hornbrook Mark C. , Fishman Paul A. , Ritzwoller Debra P. , O'Keeffe Rossetti Maureen C. , Elston Lafata Jennifer
Published: March 2012

BACKGROUND:

Evidence‐based guidelines recommend routine surveillance, including office visits and testing, to detect new and recurrent disease among survivors of breast and colorectal cancer. The extent to which surveillance practice is consistent with guideline recommendations or may vary by age is not known.

METHODS:

Cohorts of adult patients diagnosed with breast (n = 6205) and colorectal (n = 2297) cancer between 2000 and 2008 and treated with curative intent in 4 geographically diverse managed care environments were identified via tumor registries. Kaplan‐Meier estimates were used to describe time to initial and subsequent receipt of surveillance services. Cox proportional hazards models evaluated the relation between patient characteristics and receipt of metastatic screening.

RESULTS:

Within 18 months of treatment, 87.2% of breast cancer survivors received recommended mammograms, with significantly higher rates noted for patients aged 50 years to 65 years. Among survivors of colorectal cancer, only 55.0% received recommended colon examinations, with significantly lower rates for those aged ≥ 75 years. The majority of breast (64.7%) and colorectal (73.3%) cancer survivors received nonrecommended metastatic disease testing. In patients with breast cancer, factors associated with metastatic disease testing include white race (hazards ratio [HR], 1.13), comorbidities (HR, 1.17), and younger age (HR, 1.13; 1.15; 1.13 for age groups: <50, 50–64, and 65–74 respectively). In those with colorectal cancer, these factors included younger age (HR, 1.31; 1.25 for age groups: <50 and 50–64 respectively) and comorbidities (HR, 1.10).

CONCLUSIONS:

Among an insured population, wide variation regarding the use of surveillance care was found by age and relative to guideline recommendations. Breast cancer survivors were found to have high rates of both guideline‐recommended recurrence testing and non–guideline‐recommended metastatic testing. Only approximately 50% of colorectal cancer survivors received recommended tests but greater than 67% received metastatic testing. Cancer 2012. © 2012 American Cancer Society.
A high‐productivity task‐based programming model for clusters
Authors: Tejedor Enric , Farreras Montse , Grove David , Badia Rosa M. , Almasi Gheorghe , Labarta Jesus
Published: March 2012

Programming for large‐scale, multicore‐based architectures requires adequate tools that offer ease of programming and do not hinder application performance. StarSs is a family of parallel programming models based on automatic function‐level parallelism that targets productivity. StarSs deploys a data‐flow model: it analyzes dependencies between tasks and manages their execution, exploiting their concurrency as much as possible.

This paper introduces Cluster Superscalar (ClusterSs), a new StarSs member designed to execute on clusters of SMPs (Symmetric Multiprocessors). ClusterSs tasks are asynchronously created and assigned to the available resources with the support of the IBM APGAS runtime, which provides an efficient and portable communication layer based on one‐sided communication.

We present the design of ClusterSs on top of APGAS, as well as the programming model and execution runtime for Java applications. Finally, we evaluate the productivity of ClusterSs, both in terms of programmability and performance and compare it to that of the IBM X10 language. Copyright © 2012 John Wiley & Sons, Ltd.
Impact of parasitics on even symmetric split‐capacitor arrays
Authors: Rodríguez‐Pérez Alberto , Delgado‐Restituto Manuel , Medeiro Fernando
Published: March 2012

This paper analyzes the impact of parasitic capacitances in the performance of split capacitive‐based digital‐to‐analog converter arrays and presents a procedure for the optimal sizing of these structures for given linearity specifications. It also demonstrates that parasitics are often the main responsible for the nonlinear behavior of these arrays, particularly for low‐to‐medium resolution converters. In order to validate the analysis, two versions of a complete low‐power, low‐voltage successive‐approximation register analog‐to‐digital converter (ADC), intended for a disposable multi‐channel bio‐medical monitoring system, have been fabricated in a 0.35 µm standard complementary metal‐oxide‐semiconductor technology. The only difference between these two prototypes is that in one of them, the capacitive array is surrounded by dummy capacitors, while in the other prototype is not. Hence, the former achieves better mismatch performance at the expense of increased parasitics. The experimental results demonstrate that the version without dummy capacitors obtains higher effective resolution than the ADC with dummies, the power consumption being essentially the same for both prototypes, namely: 130nW at 2kS/s from a 1‐V supply. These results are in full agreement with the analysis reported in the paper and confirm the proposed sizing procedure. Copyright © 2012 John Wiley & Sons, Ltd.
Development of lead‐free BaTiO3 ceramics possessing enhanced piezoelectric properties
Authors: Takahashi Hirofumi
Published: March 2012

Due to recent environmental issues, many research findings on non‐lead‐based materials have appeared. The author also reported the possibility of improvement of piezoelectric materials by microwave (MW) sintering. We checked the relationships between the domain size and piezoelectric constant d33 in BaTiO3 ceramics, and the grain boundary and domain properties of ceramics, which are reported herein. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(4): 20–26, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10418
Selective killing of p53‐deficient cancer cells by SP600125
Authors: Jemaà Mohamed , Vitale Ilio , Kepp Oliver , Berardinelli Francesco , Galluzzi Lorenzo , Senovilla Laura , Mariño Guillermo , Malik Shoaib Ahmad , Rello‐Varona Santiago , Lissa Delphine , Antoccia Antonio , Tailler Maximilien , Schlemmer Frederic , Harper Francis , Pierron Gérard , Castedo Maria , Kroemer Guido
Published: March 2012

The genetic or functional inactivation of p53 is highly prevalent in human cancers. Using high‐content videomicroscopy based on fluorescent TP53+/+ and TP53−/− human colon carcinoma cells, we discovered that SP600125, a broad‐spectrum serine/threonine kinase inhibitor, kills p53‐deficient cells more efficiently than their p53‐proficient counterparts, in vitro. Similar observations were obtained in vivo, in mice carrying p53‐deficient and ‐proficient human xenografts. Such a preferential cytotoxicity could be attributed to the failure of p53‐deficient cells to undergo cell cycle arrest in response to SP600125. TP53−/− (but not TP53+/+) cells treated with SP600125 became polyploid upon mitotic abortion and progressively succumbed to mitochondrial apoptosis. The expression of an SP600125‐resistant variant of the mitotic kinase MPS1 in TP53−/− cells reduced SP600125‐induced polyploidization. Thus, by targeting MPS1, SP600125 triggers a polyploidization program that cannot be sustained by TP53−/− cells, resulting in the activation of mitotic catastrophe, an oncosuppressive mechanism for the eradication of mitosis‐incompetent cells.
MRT letter: Extended depth from focus reconstruction method for stretch zone measurement in 15‐5PH steel
Authors: De Oliveira Caltabiano Pietro Carelli Reis , Rosa Paulo Henrique Santos , De Campos Kamila Amato , De Oliveira Hein Luis Rogerio
Published: March 2012

The stretch zone width (SZW) data for 15‐5PH steel CTOD specimens fractured at −150°C to + 23°C temperature were measured based on focused images and 3D maps obtained by extended depth‐of‐field reconstruction from light microscopy (LM) image stacks. This LM‐based method, with a larger lateral resolution, seems to be as effective for quantitative analysis of SZW as scanning electron microscopy (SEM) or confocal scanning laser microscopy (CSLM), permitting to clearly identify stretch zone boundaries. Despite the worst sharpness of focused images, a robust linear correlation was established to fracture toughness (KC) and SZW data for the 15‐5PH steel tested specimens, measured at their center region. The method is an alternative to evaluate the boundaries of stretched zones, at a lower cost of implementation and training, since topographic data from elevation maps can be associated with reconstructed image, which summarizes the original contrast and brightness information. Finally, the extended depth‐of‐field method is presented here as a valuable tool for failure analysis, as a cheaper alternative to investigate rough surfaces or fracture, compared to scanning electron or confocal light microscopes. Microsc. Res. Tech. 75:1155–1158, 2012. © 2012 Wiley Periodicals, Inc.
Treatment with ginseng total saponins reduces the secondary brain injury in rat after cortical impact
Authors: Xia Lei , Jiang Zheng‐Lin , Wang Guo‐Hua , Hu Bao‐Yin , Ke Kai‐Fu
Published: March 2012

The present study was designed to investigate the neuroprotective effect of ginseng total saponins (GTSs) and its underlying mechanisms in a rat model of traumatic brain injury (TBI). Rats were injected with GTSs (20 mg/kg, i.p.) or vehicle for 14 days after TBI. Neurological functions were determined using beam balance and prehensile traction tests at 1–14 days after trauma. Brain samples were extracted at 1 day after trauma for determination of water content, Nissl staining, enzyme‐linked immunosorbent assay, immunohistochemistry, terminal deoxynucleotidyl transferase‐mediated biotin‐dUTP nick end labeling, and measurement of oxidative stress variables and inflammatory cytokines. Moreover, the dose response of the neuroprotective effect and time window of the efficacy of GTSs were also determined. We found that treatment of GTSs 1) improved the neurological function with an effective dosage of 5–80 mg/kg and an efficacy time window of 3–6 hr after TBI; 2) reduced brain water content and neuronal loss in the hippocampal CA3 area; 3) increased the activity of superoxide dismutase and decreased the activity of nitric oxide synthase and the amount of malondialdehyde and nitric oxide; 4) down‐regulated interleukin‐1β, interleukin‐6, and tumor necrosis factor‐α and upregulated interleukin‐10 in the cortical area surrounding the injured core; and 5) inhibited the apoptotic cell death and expression of caspase‐3 and bax and raised the expression of bcl‐2. These findings suggest that administration of GTSs after TBI could reduce the secondary injury through inhibiting oxidative and nitrative stress, attenuating inflammatory response, and reducing apoptotic cell death. © 2012 Wiley Periodicals, Inc.
The nomenclature of venous flow‐through flaps: Updated classification and review of the literature
Authors: Goldschlager Romi , Rozen Warren M. , Ting Jeannette W.C. , Leong James
Published: March 2012

Venous flow‐through flaps (venous flaps) are useful reconstructive options, particularly in the repair of defects with segmental vessel loss. They are relatively easy to harvest and confer several benefits at the donor site. However, given that they are based on a single central vein, their survival is notoriously unreliable and they are susceptible to ischemia and venous congestion. Various designs have been suggested to improve the circulatory physiology, and hence survival, of venous flap. More recent designs involve adaptations to the arrangement and number of efferent veins draining arterialized venous flaps. The most commonly used classification system for venous flaps, proposed by Chen, Tang, and Noordhoff, does not afford adequate description of these alternate designs. This article offers a classification system that can incorporate all reported modifications to venous flaps. This simple adaptation to the classification system proposed by Chen et al. restores its usefulness in describing modern variations to venous flap design. © 2012 Wiley Periodicals, Inc. Microsurgery, 2012.
The long‐term functional recovery of repair of sciatic nerve transection with biogenic conduits
Authors: Penna Vincenzo , Wewetzer Konstantin , Munder Beatrix , Stark G. Bjoern , Lang Eva M.
Published: March 2012

Introduction:

The aim of this study was to evaluate long‐term regenerative capacity over a 15‐mm nerve gap of an autologous nerve conduit, the biogenic conduit (BC), 16 weeks after sciatic nerve transection in the rat.

Methods:

A 19‐mm long polyvinyl chloride (PVC) tube was implanted parallely to the sciatic nerve. After implantation, a connective tissue cover developed around the PVC‐tube, the so‐called BC. After removal of the PVC‐tube the BCs filled with fibrin (n = 8) were compared to autologous nerve grafts (n = 8). Sciatic functional index (SFI) was evaluated every 4 weeks, histological evaluation was performed at 16 weeks postimplantation. Regenerating axons were visualized by retrograde labelling.

Results:

SFI revealed no significant differences. Nerve area and axon number in the BC group were significantly lower than in the autologous nerve group (P < 0.05; P < 0.01). Analysis of myelin formation showed no significant difference in both groups. Analysis of N‐ratio revealed lower values in the BC group (P < 0.001).

Conclusion:

This study reveals the suitability of BC for nerve gap bridging over a period of 16 weeks with functional recovery to comparable extent as the autologous nerve graft despite impaired histomorphometric parameters. © 2012 Wiley Periodicals, Inc. Microsurgery, 2012.
Characterization and thermal‐oxidative degradation behavior of poly(ethylene terephthalate‐co‐4,4′‐bibenzoate) prepared via direct esterification technique
Authors: Dai Junming , Li Guang , Yang Shenglin , Jiang Jianming
Published: March 2012

A series of poly(ethylene terephthalate‐co‐4,4′‐bibenzoate)s (PETBBs) were prepared via direct esterification from the monomers of terephthalic acid (TPA), 4,4′‐biphenyl dicarboxylic acid (BPDA), and ethylene glycol (EG) with different molar ratios. The chemical compositions of the obtained PETBBs, investigated by H1‐NMR, were identical with the feed ratio, and the high molecular weights of PETBBs were confirmed by GPC analysis. The glass transition, crystallization, and melting behavior of them were measured by DSC; the results indicated that, in the range of 5–25 mol% of BPDA addition, the glass transition temperature (Tg) increased almost linearly and the melting temperature (Tm) decreased with increasing content of BPDA unit. As expected, the crystallization of PETBB became difficult with increasing introduction of BPDA, explained by higher crystallization temperature and smaller crystallization enthalpy from the glassy state. This decrease of crystallization rate may be beneficial to film processing. Moreover, owing to the introduction of rigid‐rod BPDA unit, the initial and maximum thermal‐oxidative decomposition temperatures were enhanced. The kinetic analysis of the thermal‐oxidative degradation indicated that the apparent activation energies of degradation for these PETBBs became higher than that of PET. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Rheological behavior of polypropylene nanocomposites at low concentration of surface modified carbon nanotubes
Authors: Thomas Selvin P. , Girei Salihu Adamu , Atieh Muataz Ali , De S.K. , Al‐Juhani Abdulhadi
Published: March 2012

This article reports the rheological behavior of nanocomposites of isotactic polypropylene with both unmodified multiwall carbon nanotubes (CNTs) and phenol and 1‐octadecanol (C18) functionalized CNT (f‐CNT) at 0.1, 0.25, 1.0, and 5.0 wt% of the nanofillers. The incorporation of CNT at low loadings of 0.1 and 0.25 wt% decreases the storage and loss modulus and complex viscosity of the system, especially for the case of using f‐CNT. Out of the two types of functionalizations, C18 functionalization registers the lowest modulus and viscosity and displays processing aid behavior at 0.1 wt% loading, which is believed to be due to the disruption of the polymer entanglements. As the nanofiller loading increases to 1 wt%, the disruption of polymer entanglements effect is balanced by the hydrodynamic effect and subsequently neat polypropylene (PP), and the filled PP systems show similar modulus and complex viscosity. As the nanofiller loading increases further to 5 wt%, the hydrodynamic effect becomes the dominating factor, and the modulus and the complex viscosity of the nanofilled system become greater than that of neat PP. Results suggest that the 0.1 wt% loading of C18 f‐CNT could be a useful processing aid additive for improving polypropylene processability. POLYM. ENG. SCI., 52:1868–1873, 2012. © 2012 Society of Plastics Engineers
Enhanced fatigue life of carbon nanotube‐reinforced epoxy composites
Authors: Loos M.R. , Yang J. , Feke D.L. , Manas‐Zloczower I.
Published: March 2012

The effects of carbon nanotube (CNT) inclusion on cyclic fatigue behavior and the residual mechanical properties of epoxy composites after different degrees of fatigue have been studied. Tension–tension cyclic fatigue tests were conducted at various load levels (25–50 MPa) to establish the relationship between stress and the number of cycles to failure (S–N curves). The residual strength and modulus were measured after loading at 30 MPa for 5000, 15,000, and 25,000 cycles. The incorporation of a small amount of CNTs increased the fatigue life of epoxy in the high‐cycle, low‐stress‐amplitude regime by 1550%. Micrographs indicate the key mechanisms for enhancement in fatigue life such as CNT crack‐bridging and pullout. POLYM. ENG. SCI., 52:1882–1887, 2012. © 2012 Society of Plastics Engineers
Geolocation‐aware security in a netcentric small unmanned‐aerial‐system for RF emitters
Authors: Liang Jing
Published: March 2012

Enhancing security requires sensing devices surveilling over critical infrastructures for early warning of radio frequency (RF) emitter geolocations. Conventional geolocation of RF emitters has adopted active methodologies by illuminating targets, such as radar sensors. However, active geolocation draws unwanted attention of adversary, thus highly increases threats and vulnerabilities of the sensing devices. As security issues become a central concern in sensing applications, we propose a small unmanned‐aerial‐system for passive geolocation of RF emitters. Multiple electronic surveillance sensors are mounted on small unmanned‐aerial‐vehicles (UAVs) to provide geolocation awareness. Both sensors‐to‐UAV and UAVs‐to‐fusion‐center communications are investigated. Different with previous studies, our approach is based on an empirical path loss and log‐normal shadowing model, from a wireless communication and signal processing vision. The communication degradation from UAV to fusion center has been taken into consideration other than assuming lossless performance. The analyzed geolocation error and the error probability of distance shows that this approach provides robust performance at high frequencies, thus offers an effective solution for the security issue in RF emitter geolocation. Copyright © 2012 John Wiley & Sons, Ltd.
Comparison of multicast/broadcast services in Long Term Evolution Advanced and IEEE 802.16m networks
Authors: Calabuig Jorge , Monserrat Jose F. , Martín‐Sacristán David , Olmos Joan
Published: March 2012

This paper performs a comparison of multicast/broadcast services (MBS) support in Long Term Evolution Advanced (LTE‐A) and Worldwide Interoperability for Microwave Access (WiMAX) IEEE 802.16m. Firstly, the main technical features of both standards concerning MBS operation are presented. It is shown that WiMAX offers higher unicast/MBS multiplexing flexibility as it supports both frequency and time multiplexing schemes, whereas LTE‐A only includes time multiplexing. Besides, only WiMAX supports multi‐antenna transmission. Next, the results of two simulation‐based assessments are presented. In the former, it is considered a scenario with all cells transmitting the same MBS service. The effect of inter‐site distance (ISD) on the maximum MBS data rate is evaluated. Results show that WiMAX configurations outperform LTE‐A for small ISD. This is because WiMAX provides a higher number of resources dedicated to data transmission for the same bandwidth. Furthermore, some WiMAX configurations support two spatially multiplexed data streams. With higher ISDs, LTE‐A outperforms single‐stream WiMAX configurations. In the second assessment, a MBSFN area surrounded by interfering cells is considered to compare unicast/MBS multiplexing performance. The higher maximum MBS data rate is achieved in WiMAX with time division multiplexing, which is precisely the only alternative included in LTE‐A. Copyright © 2012 John Wiley & Sons, Ltd.
Towards a precise lattice determination of the leading hadronic contribution to (g − 2)
μ
Authors: Morte Michele Della , Jäger Benjamin , Jüttner Andreas , Wittig Hartmut
Published: March 2012

Abstract

We report on our computation of the leading hadronic contribution to the anomalous magnetic moment of the muon using two dynamical flavours of non-perturbatively O(a) improved Wilson fermions. The strange quark is introduced in the quenched approximation. Partially twisted boundary conditions are applied to improve the momentum resolution in the relevant integral. Our results, obtained at three different values of the lattice spacing, allow for a preliminary study of discretization effects. We explore a wide range of lattice volumes, namely 2 fm ≤ L ≤ 3 fm, with pion masses from 600 to 280 MeV and discuss different chiral extrapolations to the physical point. We observe a non-trivial dependence of
$a_\mu^{HLO}$
on m

π
especially for small pion masses. The final result,
$a_\mu^{HLO} = 618\left( {64} \right) \times {10^{ - 10}}$
, is obtained by considering only the quark connected contribution to the vacuum polarization. We present a detailed analysis of systematic errors and discuss how they can be reduced in future simulations.
Constraints on substrate transfer revisited
Authors: SIEGEL JEFF
Published: March 2012

In an article in this journal, Bao (2005) proposes a constraint on functional transfer that he claims accounts for features of colloquial Singapore English (and other language contact varieties) better than the congruence constraint proposed by Siegel (1999) and subsequently developed in later works (e.g. Siegel 2003, 2008a). More specifically, Bao argues that the requirement of surface syntactic similarity for transfer is too strong. His analysis uses Mandarin to exemplify the Chinese substrate languages that were the source of transfer, following the view that there is a universal Chinese grammar (Chao 1968: 13). However, the present article shows that Bao's claim is unjustified because the actual source of transfer was a variety of Chinese that differs significantly from Mandarin in the area of grammar he examined.
Democratization and Multilateral Security
Authors: Alcañiz Isabella
Published: March 2012

Does democratization increase commitment to multilateral security? In this article, the author argues that democratic transitions increase the incentives of states to cooperate in multilateral security and that this is observable in the rate at which new democracies ratify international treaties of arms control, nuclear nonproliferation, and disarmament. New democrats, she asserts, seek a positive international reputation as an insurance mechanism against future regime reversals. By becoming “good citizens” of the global system, newly elected democratic leaders seek to expose potential conspirators to the possibility of diplomatic and economic sanctions if they were to attempt to reverse the transition. First, using original data on the ratification rates of 201 states for twenty major arms control, nonproliferation, and disarmament treaties, the present study shows conclusively that new democracies outpace older democracies and all autocracies in committing to multilateral security. Second, the study empirically tests whether the swift ratification of security treaties works as a consolidation strategy and finds that, indeed, it does. That is, new democracies that commit to nonproliferation and arms control treaties are less likely to experience a regime reversal.
‘To regulate and confirm inequality’? A regional history of geriatric hospitals under the English National Health Service,c.1948–c.1975
Authors: GORSKY MARTIN
Published: March 2012

The post-war history of hospital care for older people in Britain in the first phase of its National Health Service (NHS) emphasises a detrimental Poor Law legacy. This article presents a regional study, based on the South West of England, of the processes by which Victorian workhouses became the basis of geriatric hospital provision under the NHS. Its premise is that legislative and medical developments provided opportunities for local actors to discard the ‘legacy’, and their limited success in doing so requires explanation. Theoretical perspectives from the literature are introduced including political economy approaches; historical sociology of the medical profession; and path dependence. Analysis of resource allocation decisions shows a persistent tendency to disadvantage these institutions by comparison with acute care hospitals and services for mothers and children, although new ideas about geriatric medicine had some impact locally. Quantitative and qualitative data are used to examine policies towards organisation, staffing and infrastructural improvements, suggesting early momentum was not maintained. Explanations lie partly with national financial constraints and partly with the regional administrative arrangements following the NHS settlement which perpetuated existing divisions between agencies.
Semigroup algebras of finite ample semigroups
Authors: Guo Xiaojiang , Chen Lin
Published: March 2012

An adequate semigroup S is called ample if ea = a(ea)* and ae = (ae)†a for all a ∈ S and e ∈ E(S). Inverse semigroups are exactly those ample semigroups that are regular. After obtaining some characterizations of finite ample semigroups, it is proved that semigroup algebras of finite ample semigroups have generalized triangular matrix representations. As applications, the structure of the radicals of semigroup algebras of finite ample semigroups is obtained. In particular, it is determined when semigroup algebras of finite ample semigroup are semiprimitive.
Extraction of multi-word expressions from small parallel corpora
Authors: TSVETKOV YULIA , WINTNER SHULY
Published: March 2012

We present a general, novel methodology for extracting multi-word expressions (MWEs) of various types, along with their translations, from small, word-aligned parallel corpora. Unlike existing approaches, we focus on misalignments; these typically indicate expressions in the source language that are translated to the target in a non-compositional way. We introduce a simple algorithm that proposes MWE candidates based on such misalignments, relying on 1:1 alignments as anchors that delimit the search space. We use a large monolingual corpus to rank and filter these candidates. Evaluation of the quality of the extraction algorithm reveals significant improvements over naïve alignment-based methods. The extracted MWEs, with their translations, are used in the training of a statistical machine translation system, showing a small but significant improvement in its performance.
AIRS impact on analysis and forecast of an extreme rainfall event (Indus River Valley, Pakistan, 2010) with a global data assimilation and forecast system
Authors: Reale O. , Lau K. M. , Susskind J. , Rosenberg R.
Published: March 2012

A set of data assimilation and forecast experiments is performed with the NASA Global data assimilation and forecast system GEOS‐5, to compare the impact of different approaches toward assimilation of Atmospheric Infrared Sounder (AIRS) data. The impact is first assessed globally on a sample of more than forty forecasts per experiment, through the standard 500 hPa anomaly correlation metrics. Next, the focus is on precipitation analysis and precipitation forecast skill relative to one particular event: an extreme rainfall episode which occurred in late July 2010 in Pakistan, causing massive floods along the Indus River Valley. Results show that, in addition to improving the global forecast skill, the assimilation of quality‐controlled AIRS temperature retrievals obtained under partly cloudy conditions produce better precipitation analyses, and substantially better 7‐day forecasts, than assimilation of clear‐sky radiances. The improvement of precipitation forecast skill up to 7 days is very significant in the tropics, and is caused by an improved representation, attributed to cloudy retrieval assimilation, of two contributing mechanisms: the low‐level moisture advection, and the concentration of moisture over the area in the days preceding the precipitation peak.
Molecular Brain Imaging in the Multimodality Era
Authors: Price Julie C
Published: March 2012

Multimodality molecular brain imaging encompasses in vivo visualization, evaluation, and measurement of cellular/molecular processes. Instrumentation and software developments over the past 30 years have fueled advancements in multimodality imaging platforms that enable acquisition of multiple complementary imaging outcomes by either combined sequential or simultaneous acquisition. This article provides a general overview of multimodality neuroimaging in the context of positron emission tomography as a molecular imaging tool and magnetic resonance imaging as a structural and functional imaging tool. Several image examples are provided and general challenges are discussed to exemplify complementary features of the modalities, as well as important strengths and weaknesses of combined assessments. Alzheimer's disease is highlighted, as this clinical area has been strongly impacted by multimodality neuroimaging findings that have improved understanding of the natural history of disease progression, early disease detection, and informed therapy evaluation.
Electric field effects in low resistance CoFeB-MgO magnetic tunnel junctions with perpendicular anisotropy
Authors: Meng H. , Sbiaa R. , Akhtar M. A. K. , Liu R. S. , Naik V. B. , Wang C. C.
Published: March 2012

We have investigated the electric field effects in low resistance perpendicular magnetic tunnel junction (MTJ) devices and found that the electric field can effectively reduce the coercivity (Hc) of free layer (FL) by 30% for a bias voltage Vb = −0.2 V. In addition, the bias field (Hb) on free layer is almost linearly dependent on Vb yet independent on the device size. The demonstrated Vb dependences of Hc and Hb in low resistance MTJ devices present the potential to extend the scalability of the electric field assisted spin transfer torque magnetic random access memory and improve its access speed.
Estimating mineralisation of organic nitrogen from biosolids and other organic wastes applied to soils in subtropical Australia
Authors: Pu Guixin , Bell Mike , Barry Glenn , Want Peter
Published: March 2012

One major benefit of land application of biosolids is to supply nitrogen (N) for agricultural crops, and understanding mineralisation processes is the key for better N-management strategies. Field studies were conducted to investigate the process of mineralisation of three biosolids products (aerobic, anaerobic, and thermally dried biosolids) incorporated into four different soils at rates of 7–90 wet t/ha in subtropical Queensland. Two of these studies also examined mineralisation rates of commonly used organic amendments (composts, manures, and sugarcane mill muds).
Organic N in all biosolids products mineralised very rapidly under ambient conditions in subtropical Queensland, with rates much faster than from other common amendments. Biosolids mineralisation rates ranged from 30 to 80% of applied N during periods ranging from 3.5 to 18 months after biosolids application; these rates were much higher than those suggested in the biosolids land application guidelines established by the NSW EPA (15% for anaerobic and 25% for aerobic biosolids). There was no consistently significant difference in mineralisation rate between aerobic and anaerobic biosolids in our studies. When applied at similar rates of N addition, other organic amendments supplied much less N to the soil mineral N and plant N pools during the crop season.
A significant proportion of the applied biosolids total N (up to 60%) was unaccounted for at the end of the observation period. High rates of N addition in calculated Nitrogen Limited Biosolids Application Rates (850–1250 kg N/ha) resulted in excessive accumulation of mineral N in the soil profile, which increases the environmental risks due to leaching, runoff, or gaseous N losses. Moreover, the rapid mineralisation of the biosolids organic N in these subtropical environments suggests that biosolids should be applied at lower rates than in temperate areas, and that care must be taken with the timing to maximise plant uptake and minimise possible leaching, runoff, or denitrification losses of mineralised N.
Regional mtDNA SNP differentiation in European Atlantic salmon (Salmo salar): an assessment of potential utility for determination of natal origin
Authors: Verspoor Eric , Consuegra Sonia , Fridjonsson Olafur , Hjorleifsdottir Sigridur , Knox David , Olafsson Kristinn , Tompsett Scott , Wennevik Vidar , Garcia de Leaniz Carlos
Published: March 2012

Verspoor, E., Consuegra, S., Fridjonsson, O., Hjorleifsdottir, S., Knox, D., Olafsson, K., Tompsett, S., Wennevik, V., and Garciá de Leániz, C. 2012. Regional mtDNA SNP differentiation in European Atlantic salmon (Salmo salar): an assessment of potential utility for determination of natal origin. – ICES Journal of Marine Science, 69: 1625–1636. The Atlantic salmon, Salmo salar, shows geographically structured differentiation at various classes of molecular genetic variation, among and within river stocks. Nuclear microsatellite locus variation at multiple loci has been exploited for more than a decade as a marker for the continental origin of fish caught at sea in distant-water fisheries. However, a simpler, more cost-effective, but still accurate, assignment can be obtained using a single microsatellite locus in combination with a mitochondrial DNA (mtDNA) single-nucleotide polymorphism (SNP) detected by restriction enzyme digestion. Following on from this, a preliminary study was made of the potential for using mtDNA SNP variation to enhance the resolving power and cost-effectiveness of within-continent assignment of European salmon as determined using microsatellites. Variation in 20 mtDNA regions, encompassing ∼43% of this genome, in 330 salmon from 29 rivers across Europe, was analysed. High levels of inter-individual and inter-river variation were found, as well as evidence of regional differentiation paralleling observed microsatellite differentiation. The observations indicate scope for using mtDNA SNPs along with microsatellites for genetically based assignment of European salmon to region and river of natal origin, but further study is needed.
Tissue-Specific Transcriptome Analysis in Nodules of Lotus japonicus
Authors: Takanashi Kojiro , Takahashi Hirokazu , Sakurai Nozomu , Sugiyama Akifumi , Suzuki Hideyuki , Shibata Daisuke , Nakazono Mikio , Yazaki Kazufumi
Published: March 2012

Legume plants can establish symbiotic nitrogen fixation (SNF) with rhizobia mostly in root nodules, where rhizobia-infected cells are accompanied by uninfected cells in a mosaic pattern. Inside the mature nodules of the legume, carbon and nitrogen nutrients between host plant cells and their resident bacteria are actively exchanged. To elucidate the metabolite dynamics relevant for SNF in nodules, three tissues from a nodule of a model legume, Lotus japonicus, were isolated using laser microdissesction, and transcriptome analysis was done by an oligoarray of 60-mer length representing 21,495 genes. In our tissue-specific profiling, many genes were identified as being expressed in nodules in a spatial-specific manner. Among them, genes coding for metabolic enzymes were classified according to their function, and detailed data analysis showed that a secondary metabolic pathway was highly activated in the nodule cortex. In particular, a number of metabolic genes for a phenylpropanoid pathway were found as highly expressed genes accompanied by those encoding putative transporters of secondary metabolites. These data suggest the involvement of a novel physiological function of phenylpropanoids in SNF. Moreover, five representative genes were selected, and detailed tissue-specific expression was characterized by promoter-β-glucuronidase experiments. Our results provide a new data source for investigation of both nodule differentiation and tissue-specific physiological functions in nodules.
Peptide- and saccharide-conjugated dendrimers for targeted drug delivery: a concise review
Authors: Liu Jie , Gray Warren D. , Davis Michael E. , Luo Ying
Published: March 2012

Dendrimers comprise a category of branched materials with diverse functions that can be constructed with defined architectural and chemical structures. When decorated with bioactive ligands made of peptides and saccharides through peripheral chemical groups, dendrimer conjugates are turned into nanomaterials possessing attractive binding properties with the cognate receptors. At the cellular level, bioactive dendrimer conjugates can interact with cells with avidity and selectivity, and this function has particularly stimulated interests in investigating the targeting potential of dendrimer materials for the design of drug delivery systems. In addition, bioactive dendrimer conjugates have so far been studied for their versatile capabilities to enhance stability, solubility and absorption of various types of therapeutics. This review presents a brief discussion on three aspects of the recent studies to use peptide- and saccharide-conjugated dendrimers for drug delivery: (i) synthesis methods, (ii) cell- and tissue-targeting properties and (iii) applications of conjugated dendrimers in drug delivery nanodevices. With more studies to elucidate the structure–function relationship of ligand–dendrimer conjugates in transporting drugs, the conjugated dendrimers hold promise to facilitate targeted delivery and improve drug efficacy for discovery and development of modern pharmaceutics.