bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacokinetics and Safety of Intravenous Ceftolozane-Tazobactam in Healthy Adult Subjects following Single and Multiple Ascending Doses
Authors: Miller Benjamin , Hershberger Ellie , Benziger David , Trinh MyMy , Friedland Ian
Published: March 2012

The pharmacokinetics and safety of ceftolozane, a novel cephalosporin, and tazobactam, a β-lactamase inhibitor, alone and in combination as a 2:1 ratio in single doses of up to 2,000 and 1,000 mg of ceftolozane and tazobactam, respectively, and multiple doses of up to 3,000 and 1,500 mg of ceftolozane and tazobactam, respectively, per day were evaluated in healthy adult subjects. In part 1, groups of six subjects each received single ascending doses of ceftolozane, tazobactam, and ceftolozane-tazobactam in a within-cohort crossover design. In part 2, groups of 5 or 10 subjects each received multiple doses of ceftolozane, tazobactam, or ceftolozane-tazobactam for 10 days. After a single dose of ceftolozane alone, the ranges of mean values for half-life (2.48 to 2.64 h), the total clearance (4.35 to 6.01 liters/h), and the volume of distribution at steady state (11.0 to 14.1 liters) were consistent across dose levels and similar to those observed when ceftolozane was coadministered with tazobactam. Mean values after multiple doses for ceftolozane alone and ceftolozane-tazobactam were similar to those seen following a single dose. The pharmacokinetics of the dosing regimens evaluated were dose proportional and linear. Ceftolozane-tazobactam was well tolerated and systemic adverse events were uncommon. Mild infusion-related adverse events were the most commonly observed following multiple-dose administration. Adverse events were not dose related, and no dose-limiting toxicity was identified.
The Relative Contributions of Physical Structure and Cell Density to the Antibiotic Susceptibility of Bacteria in Biofilms
Authors: Kirby Amy E. , Garner Kimberly , Levin Bruce R.
Published: March 2012

For many bacterial infections, noninherited mechanisms of resistance are responsible for extending the term of treatment and in some cases precluding its success. Among the most important of these noninherited mechanisms of resistance is the ability of bacteria to form biofilms. There is compelling evidence that bacteria within biofilms are more refractory to antibiotics than are planktonic cells. Not so clear, however, is the extent to which this resistance can be attributed to the structure of biofilms rather than the physiology and density of bacteria within them. To explore the contribution of the structure of biofilms to resistance in a quantitative way, we developed an assay that compares the antibiotic sensitivity of bacteria in biofilms to cells mechanically released from these structures. Our method, which we apply to
Escherichia coli
and
Staphylococcus aureus
each with antibiotics of five classes, controls for the density and physiological state of the treated bacteria. For most of the antibiotics tested, the bacteria in biofilms were no more resistant than the corresponding populations of planktonic cells of similar density. Our results, however, suggest that killing by gentamicin, streptomycin, and colistin is profoundly inhibited by the structure of biofilms; these drugs are substantially more effective in killing bacteria released from biofilms than cells within these structures.
Nasopharyngeal Colonization Elicits Antibody Responses to Staphylococcal and Pneumococcal Proteins That Are Not Associated with a Reduced Risk of Subsequent Carriage
Authors: Prevaes Sabine M. P. J. , van Wamel Willem J. B. , de Vogel Corné P. , Veenhoven Reinier H. , van Gils Elske J. M. , van Belkum Alex , Sanders Elisabeth A. M. , Bogaert Debby
Published: March 2012

Knowledge of the immunological correlates of
Staphylococcus aureus
and
Streptococcus pneumoniae
colonization is required for the search for future protein vaccines. We evaluated natural antibody levels against pneumococcal and staphylococcal proteins in relation to previous bacterial colonization with both pathogens. In a randomized controlled trial, nasopharyngeal samples were obtained from children at 1.5, 6, 12, 18, and 24 months and cultured for
S. aureus
and
S. pneumoniae
. Approximately 50% of the children were PCV7 vaccinated. Serum IgG against 18 pneumococcal and 40 staphylococcal proteins was semiquantified by Luminex technology from 111 12 month olds and 158 24 month olds. Previous culture-proven
S. aureus
colonization was associated with higher IgG levels against 6/40 staphylococcal proteins (ClfB, ClfA, Efb, CHIPS, LukD, and LukF [
P
≤ 0.001]) compared to noncarriers. Previous pneumococcal colonization was associated with increased IgG levels against 12/18 pneumococcal proteins compared to noncarriers (
P
≤ 0.003). Increasing age was associated with higher levels of antibodies to most pneumococcal proteins and lower levels of antibodies to over half the staphylococcal proteins, reflecting natural colonization dynamics. Anti-
S. pneumoniae
and anti-
S. aureus
protein antibodies at the age of 12 months were not negatively correlated with subsequent colonization with the homologous species in the following year and did not differ between PCV7-vaccinated and nonvaccinated children. Colonization with
S. aureus
and
S. pneumoniae
induces serum IgG against many proteins, predominantly proteins with immune-modulating functions, irrespective of PCV7 vaccination. None of them appeared to be protective against new acquisition with both pathogens, possibly due to the polymorphic nature of those proteins in the circulating bacterial population.
Functional Differences and Interactions between the Escherichia coli Type III Secretion System Effectors NleH1 and NleH2
Authors: Pham Thanh H. , Gao Xiaofei , Tsai Karen , Olsen Rachel , Wan Fengyi , Hardwidge Philip R.
Published: March 2012

The human pathogens enterohemorrhagic and enteropathogenic
Escherichia coli
(EHEC and EPEC), as well as the related mouse pathogen
Citrobacter rodentium
, utilize a type III secretion system (T3SS) to inject multiple effector proteins into host cells. The
E. coli
O157:H7 strain EDL933 carries two copies of non-locus of enterocyte effacement (LEE)-encoded protein H, designated NleH1 and NleH2, both of which bind to the human ribosomal protein S3 (RPS3), a subunit of NF-κB transcriptional complexes. In this study, we describe significant functional differences between NleH1 and NleH2 in their ability to regulate the host NF-κB pathway. We show that the EHEC and EPEC NleH effectors are functionally equivalent in their ability to affect RPS3 nuclear translocation. NleH1, but not NleH2, inhibited NF-κB activity without altering the kinetics of IκBα phosphorylation/degradation. We also determined that the class I PSD-95/Disc Large/ZO-1 (PDZ)-binding domain of NleH was important for its activity in the NF-κB pathway. In addition to binding RPS3, we found that NleH1 and NleH2 are able to bind to each other
in vitro
and
in vivo
, suggesting an additional mechanism by which the
E. coli
NleH effectors may regulate the extent and duration of NF-κB activation after their T3SS-dependent translocation. We also performed mouse infection experiments and established that mouse mortality and
Citrobacter
colonization were reduced in mice infected with Δ
nleH
. Complementing Δ
nleH
with NleH1 restored
Citrobacter
virulence and colonization to wild-type levels, whereas complementing with NleH2 reduced them. Taken together, our data show that NleH1 and NleH2 have pronounced functional differences in their ability to alter host transcriptional responses to bacterial infection.
Aggregatibacter actinomycetemcomitans Infection Enhances Apoptosis
In Vivo
through a Caspase-3-Dependent Mechanism in Experimental Periodontitis
Authors: Kang Jun , de Brito Bezerra Beatriz , Pacios Sandra , Andriankaja Oelisoa , Li Yu , Tsiagbe Vincent , Schreiner Helen , Fine Daniel H. , Graves Dana T.
Published: March 2012

The purpose of this study was to test the hypothesis that diabetes aggravates periodontal destruction induced by
Aggregatibacter actinomycetemcomitans
infection. Thirty-eight diabetic and 33 normal rats were inoculated with
A. actinomycetemcomitans
and euthanized at baseline and at 4, 5, and 6 weeks after inoculation. Bone loss and the infiltration of polymorphonuclear leukocytes (PMNs) in gingival epithelium were measured in hematoxylin-eosin-stained sections. The induction of tumor necrosis factor alpha (TNF-α) was evaluated by immunohistochemistry and of apoptotic cells by a TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling) assay. After
A. actinomycetemcomitans
infection, the bone loss in diabetic rats was 1.7-fold and the PMN infiltration 1.6-fold higher than in normoglycemic rats (
P
< 0.05). The induction of TNF-α was 1.5-fold higher and of apoptotic cells was up to 3-fold higher in diabetic versus normoglycemic rats (
P
< 0.05). Treatment with a caspase-3 inhibitor significantly blocked noninflammatory cell apoptosis induced by
A. actinomycetemcomitans
infection in gingival epithelium and connective tissue (
P
< 0.05). These results provide new insight into how diabetes aggravates
A. actinomycetemcomitans
-induced periodontal destruction in rats by significantly increasing the inflammatory response, leading to increased bone loss and enhancing apoptosis of gingival epithelial and connective tissue cells through a caspase-3-dependent mechanism. Antibiotics had a more pronounced effect on many of these parameters in diabetic than in normoglycemic rats, suggesting a deficiency in the capacity of diabetic animals to resist infection.
Impact of Mosquito Bites on Asexual Parasite Density and Gametocyte Prevalence in Asymptomatic Chronic Plasmodium falciparum Infections and Correlation with IgE and IgG Titers
Authors: Lawaly Ramatoulaye , Konate Lassana , Marrama Laurence , Dia Ibrahima , Diallo Diawo , Diène Sarr Fatoumata , Schneider Bradley S. , Casademont Isabelle , Diallo Mawlouth , Brey Paul T. , Sakuntabhai Anavaj , Mecheri Salah , Paul Richard
Published: March 2012

An immunomodulatory role of arthropod saliva has been well documented, but evidence for an effect on
Plasmodium
sp. infectiousness remains controversial. Mosquito saliva may orient the immune response toward a Th2 profile, thereby priming a Th2 response against subsequent antigens, including
Plasmodium
. Orientation toward a Th1 versus a Th2 profile promotes IgG and IgE proliferation, respectively, where the former is crucial for the development of an efficient antiparasite immune response. Here we assessed the direct effect of mosquito bites on the density of
Plasmodium falciparum
asexual parasites and the prevalence of gametocytes in chronic, asymptomatic infections in a longitudinal cohort study of seasonal transmission. We additionally correlated these parasitological measures with IgE and IgG antiparasite and anti-salivary gland extract titers. The mosquito biting density was positively correlated with the asexual parasite density but not asexual parasite prevalence and was negatively correlated with gametocyte prevalence. Individual anti-salivary gland IgE titers were also negatively correlated with gametocyte carriage and were strongly positively correlated with antiparasite IgE titers, consistent with the hypothesis that mosquito bites predispose individuals to develop an IgE antiparasite response. We provide evidence that mosquito bites have an impact on asymptomatic infections and differentially so for the production of asexual and sexual parasites. An increased research focus on the immunological impact of mosquito bites during asymptomatic infections is warranted, to establish whether strategies targeting the immune response to saliva can reduce the duration of infection and the onward transmission of the parasite.
Suicides by persons reported as missing prior to death: a retrospective cohort study
Authors: Sveticic Jerneja , Too Lay San , De Leo Diego
Published: March 2012

Objective

A first study to compare suicides by missing persons with other suicide cases.

Design

Retrospective cohort study for the period 1994–2007.

Geographical location

Queensland, Australia.

Population

194 suicides by missing persons and 7545 other suicides were identified through the Queensland Suicide Register and the National Coroners Information System.

Main outcome measure

χ2statistics and binary logistic regression were used to identify distinct characteristics of suicides by missing persons.

Results

Compared with other suicide cases, missing persons significantly more often died by motor vehicle exhaust gas toxicity (23.7% vs 16.4%; χ2=7.32, p<0.01), jumping from height (6.7% vs 3.2%; χ2=7.08, p<0.01) or drowning (8.2% vs 1.8%; χ2=39.53, p<0.01), but less frequently by hanging (29.4% vs 39.9%; χ2=8.82, p<0.01). They were most frequently located in natural outdoors locations (58.2% vs 11.1%; χ2=388.25, p<0.01). Persons gone missing were less likely to have lived alone at time of death (OR 0.45, 95% CI 0.26 to 0.76), yet more likely to be institutionalised (OR 3.12, 95% CI 1.28 to 7.64). They were less likely to have been physically ill (OR 0.64, 95% CI 0.43 to 0.95) or have a history of problematic consumptions of alcohol (OR 0.52, 95% CI 0.31 to 0.87). In comparison to other suicide cases, missing persons more often communicated their suicidal intent prior to death (OR 1.58, 95% CI 1.13 to 2.22).

Conclusions

Suicides by missing persons show several distinct characteristics in comparisons to other suicides. The findings have implications for development of suicide prevention strategies focusing on early identification and interventions targeting this group. In particular, it may offer assistance to police in designing risk assessment procedures and subsequent investigations of missing persons.
Protocol for the Northern Manhattan Diabetes Community Outreach Project. A randomised trial of a community health worker intervention to improve diabetes care in Hispanic adults
Authors: Palmas Walter , Teresi Jeanne A , Findley Sally , Mejia Miriam , Batista Milagros , Kong Jian , Silver Stephanie , Luchsinger Jose A , Carrasquillo Olveen
Published: March 2012

Objective

Hispanics in the USA are affected by the diabetes epidemic disproportionately, and they consistently have lower access to care, poorer control of the disease and higher risk of complications. This study evaluates whether a community health worker (CHW) intervention may improve clinically relevant markers of diabetes care in adult underserved Hispanics.

Methods and analysis

The Northern Manhattan Diabetes Community Outreach Project (NOCHOP) is a two-armed randomised controlled trial to be performed as a community-based participatory research study performed in a Primary Care Setting in Northern Manhattan (New York City). 360 Hispanic adults with poorly controlled type 2 diabetes mellitus (haemoglobin A1c >8%), aged 35–70 years, will be randomised at a 1:1 ratio, within Primary Care Provider clusters. The two study arms are (1) a 12-month CHW intervention and (2) enhanced usual care (educational materials mailed at 4-month intervals, preceded by phone calls). The end points, assessed after 12 months, are primary = haemoglobin A1c and secondary = blood pressure and low-density lipoprotein-cholesterol levels. In addition, the study will describe the CHW intervention in terms of components and intensity and will assess its effects on (1) medication adherence, (2) medication intensification, (3) diet and (4) physical activity.

Ethics and dissemination

All participants will provide informed consent; the study protocol has been approved by the Institutional Review Board of Columbia University Medical Center. CHW interventions hold great promise in improving the well-being of minority populations who suffer from diabetes mellitus. The NOCHOP study will provide valuable information about the efficacy of those interventions vis-à-vis clinically relevant end points and will inform policy makers through a detailed characterisation of the programme and its effects.

Clinical trial registration number

NCT00787475 at clinicaltrials.gov.
DERIVING SYSTEM COMPLEXITY METRIC FROM EVENTS AND ITS VALIDATION
Authors: SABHARWAL SANGEETA , SINGH SANDEEP K. , GUPTA J. P.
Published: March 2012

The event based paradigm has gathered momentum as witnessed by current efforts in areas ranging from event driven architectures, complex event processing, and business process management and modeling to grid computing, web services notifications, event stream processing and message-oriented middleware. The increasing popularity of event based systems has opened new challenging issues for them. One such issue is measuring complexity of these systems. A well-developed system should be maintainable, pluggable, scalable and less complex. In this paper, an event based approach is proposed to derive software metrics for measuring system complexity. Events taking place in a system are documented using the proposed event template. An event-flow model is constructed from event templates. The event-flow model of an event based system is represented as an event-flow graph. The proposed event-flow complexity metric for analysis model is derived from an event-flow graph. The metric has also been evaluated in terms of Weyuker's properties. Results of evaluation show that it satisfies 8 out of 9 Weyuker's properties. A prototype tool is also developed to automatically generate event interdependency matrices and compute absolute and relative complexity of an entire system. The proposed technique can be very effective especially for real time systems where lots of events take place.
EXPLORING ENTREPRENEURIAL FULFILLMENT FOR WOMEN IN INDIA: AN EMPIRICAL STUDY
Authors: PRASAD V. KANTI , NAIDU G. M. , EHRHARDT KYLE , WINKEL DOAN E. , MURTHY B. KINNERA
Published: March 2012

Drawing on social feminist theory, Indian cultural precepts, and previous research, we explore factors which may influence entrepreneurial fulfillment for women entrepreneurs in India. Results of a hierarchical regression analysis suggest that numerous network characteristics, as well as perceptions of family support, each contribute to a sense of entrepreneurial fulfillment for Indian women entrepreneurs. These factors furthermore each contributed to entrepreneurial fulfillment beyond the influence of the financial performance of the venture. Implications for understanding women entrepreneurs in emerging economies are discussed, as are practical implications for both women entrepreneurs and policy makers. We additionally present directions for future research.
THE STRATEGY CONFIGURATION OF CHINESE SMEs
Authors: TANG ZHI , HULL CLYDE EIRÍKUR
Published: March 2012

This paper investigates how Chinese SMEs configure marketing, cost-control, and innovation strategies in order to attain better organizational effectiveness. Rather than the more standard approach of suggesting that SMEs focus exclusively on one strategy, we hypothesize that when a strategy configuration is composed of multiple prioritized and related strategies, organizational effectiveness will be improved. Data collected from 133 small and medium-sized Chinese SMEs verified our hypotheses. The implications of our study for Chinese SMEs, China's policy makers, and overseas investors are discussed.
L∞-ESTIMATES FOR DIVERGENCE OPERATORS ON BAD DOMAINS
Authors: TER ELST A. F. M. , REHBERG JOACHIM
Published: March 2012

In this paper, we prove L∞-estimates for solutions of divergence operators in the case of mixed boundary conditions. In this very general setting, the Dirichlet boundary part may be arbitrarily wild, i.e. no regularity conditions have to be imposed on it.
From Context to Distance
Authors: Ienco Dino , Pensa Ruggero G. , Meo Rosa
Published: March 2012

Clustering data described by categorical attributes is a challenging task in data mining applications. Unlike numerical attributes, it is difficult to define a distance between pairs of values of a categorical attribute, since the values are not ordered. In this article, we propose a framework to learn a context-based distance for categorical attributes. The key intuition of this work is that the distance between two values of a categorical attribute
A
i
can be determined by the way in which the values of the other attributes
A
j
are distributed in the dataset objects: if they are similarly distributed in the groups of objects in correspondence of the distinct values of
A
i
a low value of distance is obtained. We propose also a solution to the critical point of the choice of the attributes
A
j
. We validate our approach by embedding our distance learning framework in a hierarchical clustering algorithm. We applied it on various real world and synthetic datasets, both low and high-dimensional. Experimental results show that our method is competitive with respect to the state of the art of categorical data clustering approaches. We also show that our approach is scalable and has a low impact on the overall computational time of a clustering task.
Return-Oriented Programming
Authors: Roemer Ryan , Buchanan Erik , Shacham Hovav , Savage Stefan
Published: March 2012

We introduce
return-oriented programming
, a technique by which an attacker can induce arbitrary behavior in a program whose control flow he has diverted, without injecting any code. A return-oriented program chains together short instruction sequences already present in a program’s address space, each of which ends in a “return” instruction.

Return-oriented programming defeats the W⊕X protections recently deployed by Microsoft, Intel, and AMD; in this context, it can be seen as a generalization of traditional return-into-libc attacks. But the threat is more general. Return-oriented programming is readily exploitable on multiple architectures and systems. It also bypasses an entire category of security measures---those that seek to prevent malicious computation by preventing the execution of malicious code.

To demonstrate the wide applicability of return-oriented programming, we construct a Turing-complete set of building blocks called gadgets using the standard C libraries of two very different architectures: Linux/x86 and Solaris/SPARC. To demonstrate the power of return-oriented programming, we present a high-level, general-purpose language for describing return-oriented exploits and a compiler that translates it to gadgets.
Efficient Attributes for Anonymous Credentials
Authors: Camenisch Jan , Groß Thomas
Published: March 2012

We extend the Camenisch-Lysyanskaya anonymous credential system such that selective disclosure of attributes becomes highly efficient. The resulting system significantly improves upon existing approaches, which suffer from a linear number of modular exponentiations in the total number of attributes. This limitation makes them unfit for many practical applications, such as electronic identity cards. Our novel approach can incorporate a large number of binary and finite-set attributes without significant performance impact. It compresses all such attributes into a single attribute base and, thus, boosts the efficiency of all proofs of possession. The core idea is to encode discrete binary and finite-set values as prime numbers. We then use the divisibility property for efficient proofs of their presence or absence. In addition, we contribute efficient methods for conjunctions and disjunctions. The system builds on the strong RSA assumption. We demonstrate the aptness of our method in realistic application scenarios, notably electronic identity cards, and show its advantages for small devices, such as smartcards and cell phones.
On importance sampling with mixtures for random walks with heavy tails
Authors: Hult Henrik , Svensson Jens
Published: March 2012

State-dependent importance sampling algorithms based on mixtures are considered. The algorithms are designed to compute tail probabilities of a heavy-tailed random walk. The increments of the random walk are assumed to have a regularly varying distribution. Sufficient conditions for obtaining bounded relative error are presented for rather general mixture algorithms. Two new examples, called the generalized Pareto mixture and the scaling mixture, are introduced. Both examples have good asymptotic properties and, in contrast to some of the existing algorithms, they are very easy to implement. Their performance is illustrated by numerical experiments. Finally, it is proved that mixture algorithms of this kind can be designed to have vanishing relative error.
Evolutionary optimization of low-discrepancy sequences
Authors: De Rainville François-Michel , Gagné Christian , Teytaud Olivier , Laurendeau Denis
Published: March 2012

Low-discrepancy sequences provide a way to generate quasi-random numbers of high dimensionality with a very high level of uniformity. The nearly orthogonal Latin hypercube and the generalized Halton sequence are two popular methods when it comes to generate low-discrepancy sequences. In this article, we propose to use evolutionary algorithms in order to find optimized solutions to the combinatorial problem of configuring generators of these sequences. Experimental results show that the optimized sequence generators behave at least as well as generators from the literature for the Halton sequence and significantly better for the nearly orthogonal Latin hypercube.
Confidence intervals for quantiles when applying variance-reduction techniques
Authors: Chu Fang , Nakayama Marvin K.
Published: March 2012

Quantiles, which are also known as values-at-risk in finance, frequently arise in practice as measures of risk. This article develops asymptotically valid confidence intervals for quantiles estimated via simulation using variance-reduction techniques (VRTs). We establish our results within a general framework for VRTs, which we show includes importance sampling, stratified sampling, antithetic variates, and control variates. Our method for verifying asymptotic validity is to first demonstrate that a quantile estimator obtained via a VRT within our framework satisfies a Bahadur-Ghosh representation. We then exploit this to show that the quantile estimator obeys a central limit theorem (CLT) and to develop a consistent estimator for the variance constant appearing in the CLT, which enables us to construct a confidence interval. We provide explicit formulae for the estimators for each of the VRTs considered.
On simulating a class of Bernstein polynomials
Authors: Goyal Vineet , Sigman Karl
Published: March 2012

Given a black box that generates independent Bernoulli samples with an unknown bias p, we consider the problem of simulating a Bernoulli random variable with bias
f
(
p
) (where
f
is a given function) using a finite (computable in advance) number of independent Bernoulli samples from the black box. We show that this is possible if and only if
f
is a Bernstein polynomial with coefficients between 0 and 1, and we explicitly give the algorithm. Our results differ from Keane and O'Brien [1994] in that our goal is more modest/stringent, since we are considering algorithms that use a
finite
number of samples as opposed to allowing a random number (such as in acceptance rejection algorithms).
The Teaching--Research--Industry--Learning Nexus in Information and Communications Technology
Authors: McGill Tanya , Armarego Jocelyn , Koppi Tony
Published: March 2012

The teaching-research nexus concept has been extensively examined in the higher education literature, and the importance of industry linkages in information and communications technology (ICT) education has also been widely discussed. However, to date there has been little recognition of the full extent of relationships between aspects of teaching, learning, research, and industry, and of the synergy possible from exploiting these relationships. Koppi and Naghdy [2009] introduced the concept of the teaching-research-industry-learning (TRIL) nexus in ICT education and this article attempts to advance understanding of the concept by exploring the literature that underpins it. The article contributes to a clearer understanding of the nature of the relationships involved as they apply to ICT education, and makes comprehensive recommendations to support strengthening the TRIL nexus in ICT education.
AuDeNTES
Authors: Mariani Leonardo , Micucci Daniela
Published: March 2012

In academic courses, students frequently take advantage of someone else’s work to improve their own evaluations or grades. This unethical behavior seriously threatens the integrity of the academic system, and teachers invest substantial effort in preventing and recognizing plagiarism.

When students take examinations requiring the production of computer programs, plagiarism detection can be semiautomated using analysis techniques such as JPlag and Moss. These techniques are useful but lose effectiveness when the text of the exam suggests some of the elements that should be structurally part of the solution. A loss of effectiveness is caused by the many common parts that are shared between programs due to the suggestions in the text of the exam rather than plagiarism.

In this article, we present the AuDeNTES anti-plagiarism technique. AuDeNTES detects plagiarism via the code fragments that better represent the individual students’ contributions by filtering from students’ submissions the parts that might be common to many students due to the suggestions in the text of the exam. The filtered parts are identified by comparing students’ submissions against a reference solution, which is a solution of the exam developed by the teachers. Specifically, AuDeNTES first produces tokenized versions of both the reference solution and the programs that must be analyzed. Then, AuDeNTES removes from the tokenized programs the tokens that are included in the tokenized reference solution. Finally, AuDeNTES computes the similarity among the filtered tokenized programs and produces a ranked list of program pairs suspected of plagiarism.

An empirical comparison against multiple state-of-the-art plagiarism detection techniques using several sets of real students’ programs collected in early programming courses demonstrated that AuDeNTES identifies more plagiarism cases than the other techniques at the cost of a small additional inspection effort.
Route planning with flexible edge restrictions
Authors: Geisberger Robert , Rice Michael N. , Sanders Peter , Tsotras Vassilis J.
Published: March 2012

In this work, we explore a new type of flexible shortest-path query, in which the query can be dynamically parameterized to constrain the type of edges that may be included in the resulting shortest path (e.g., find the shortest path in a road network that avoids toll roads and low overpasses, respective of the specified vehicle height). We extend the hierarchical preprocessing technique known as Contraction Hierarchies to efficiently support such flexible queries. We also present several effective algorithmic optimizations for further improving the overall scalability and query times of this approach, including the addition of goal-directed search techniques, search space pruning techniques, and generalizing the constraints of the local search. Experiments are presented for both the North American and the European road networks, showcasing the general effectiveness and scalability of our proposed methodology to large-scale, real-world graphs.
Exact Quantum Algorithms for the Leader Election Problem
Authors: Tani Seiichiro , Kobayashi Hirotada , Matsumoto Keiji
Published: March 2012

This article gives a separation between quantum and classical models in pure (i.e., noncryptographic) computing abilities with no restriction on the amount of available computing resources, by considering the exact solvability of the leader election problem in anonymous networks, a celebrated unsolvable problem in classical distributed computing. The goal of the leader election problem is to elect a unique leader from among distributed parties. In an anonymous network, all parties with the same number of communication links are identical. It is well-known that no classical algorithm can exactly solve (i.e., in bounded time without error) the leader election problem in anonymous networks, even if the number of parties is given. This article devises a quantum algorithm that, if the number of parties is given, exactly solves the problem for any network topology in polynomial rounds with polynomial communication/time complexity with respect to the number of parties, when the parties are connected with quantum communication links and they have the ability of quantum computing. Our algorithm works even when only an upper bound of the number of parties is given. In such a case, no classical algorithm can solve the problem even under the zero-error setting, the setting in which error is not allowed but running time may be unbounded.
Extractors and Lower Bounds for Locally Samplable Sources
Authors: De Anindya , Watson Thomas
Published: March 2012

We consider the problem of extracting randomness from sources that are efficiently samplable, in the sense that each output bit of the sampler only depends on some small numberdof the random input bits. As our main result, we construct a deterministic extractor that, given anyd-local source with min-entropykonnbits, extractsΩ(k2/nd) bits that are 2−nΩ(1)-close to uniform, providedd≤o(logn) andk≥n2/3+γ(for arbitrarily small constantsγ> 0).

Using our result, we also improve a result of Viola [2010] who proved a 1/2 −O(1/logn) statistical distance lower bound foro(logn)-local samplers trying to sample input-output pairs of an explicit boolean function, assuming the samplers use at mostn+n1−δrandom bits for some constantδ> 0. Using a different function, we simultaneously improve the lower bound to 1/2 − 2−nΩ(1)and eliminate the restriction on the number of random bits.
Static vs. dynamic type systems
Authors: Stuchlik Andreas , Hanenberg Stefan
Published: March 2012

Static type systems are essential in computer science. However, there is hardly any knowledge about the impact of type systems on the resulting piece of software. While there are authors that state that static types increase the development speed, other authors argue the other way around. A previous experiment suggests that there are multiple factors that play a role for a comparison of statically and dynamically typed language. As a follow-up, this paper presents an empirical study with 21 subjects that compares programming tasks performed in Java and Groovy - programming tasks where the number of expected type casts vary in the statically typed language. The result of the study is, that the dynamically typed group solved the complete programming tasks significantly faster for most tasks - but that for larger tasks with a higher number of type casts no significant difference could be found.
Glenohumeral Joint Preservation: A Review of Management Options for Young, Active Patients with Osteoarthritis
Authors: van der Meijden Olivier A. , Gaskill Trevor R. , Millett Peter J.
Published: March 2012

The management of osteoarthritis of the shoulder in young, active patients is a challenge, and the optimal treatment has yet to be completely established. Many of these patients wish to maintain a high level of activity, and arthroplasty may not be a practical treatment option. It is these patients who may be excellent candidates for joint-preservation procedures in an effort to avoid or delay joint replacement. Several palliative and restorative techniques are currently optional. Joint debridement has shown good results and a combination of arthroscopic debridement with a capsular release, humeral osteoplasty, and transcapsular axillary nerve decompression seems promising when humeral osteophytes are present. Currently, microfracture seems the most studied reparative treatment modality available. Other techniques, such as autologous chondrocyte implantation and osteochondral transfers, have reportedly shown potential but are currently mainly still investigational procedures. This paper gives an overview of the currently available joint preserving surgical techniques for glenohumeral osteoarthritis.
Existence and Iterative Algorithm of Solutions for a System of Generalized Nonlinear Mixed Variational‐Like Inequalities
Authors: Du Yan-Mei
Published: March 2012

We introduce and study a system of generalized nonlinear mixed variational‐like inequality problems (SGNMVLIPs) in Banach spaces. The auxiliary principle technique is applied to study the existence and iterative algorithm of solutions for the SGNMVLIP. First, the existence of solutions of the auxiliary problems for the SGNMVLIP is shown. Second, an iterative algorithm for solving the SGNMVLIP is constructed by using this existence result. Finally, not only the existence of solutions of the SGNMVLIP is shown but also the convergence of iterative sequences generated by the algorithm is also proven. The technique and results presented in this paper generalize and unify the corresponding techniques and results given in the literature.
A Prototype System for Time-Lapse Electrical Resistivity Tomographies
Authors: Luongo Raffaele , Perrone Angela , Piscitelli Sabatino , Lapenna Vincenzo
Published: March 2012

A prototype system for time-lapse acquisition of 2D electrical resistivity tomography (ERT) and time domain reflectometry (TDR) measurements was installed in a test site affected by a landslide in Basilicata region (southern Italy). The aim of the system is to monitor in real-time the rainwater infiltration into the soil and obtain information about the variation of the water content in the first layers of the subsoil and the possible influence of this variation on landslide activity. A rain gauge placed in the test site gives information on the rainfall intensity and frequency and suggests the acquisition time interval. The installed system and the preliminary results are presented in this paper.
Alternative Macroautophagic Pathways
Authors: Juenemann Katrin , Reits Eric A.
Published: March 2012

Macroautophagy is a bulk degradation process that mediates the clearance of long-lived proteins, aggregates, or even whole organelles. This process includes the formation of autophagosomes, double-membrane structures responsible for delivering cargo to lysosomes for degradation. Currently, other alternative autophagy pathways have been described, which are independent of macroautophagic key players like Atg5 and Beclin 1 or the lipidation of LC3. In this review, we highlight recent insights in indentifying and understanding the molecular mechanism responsible for alternative autophagic pathways.
Increased Mortality of Respiratory Diseases, Including Lung Cancer, in the Area with Large Amount of Ashfall from Mount Sakurajima Volcano
Authors: Higuchi Kenta , Koriyama Chihaya , Akiba Suminori
Published: March 2012

Objectives. Mount Sakurajima in Japan is one of the most active volcanoes in the world. This work was conducted to examine the effect of volcanic ash on the chronic respiratory disease mortality in the vicinity of Mt. Sakurajima.Methods. The present work examined the standardized mortality ratios (SMRs) of respiratory diseases during the period 1968–2002 in Sakurajima town and Tarumizu city, where ashfall from the volcano recorded more than 10.000 g/m2/yr on average in the 1980s.Results. The SMR of lung cancer in the Sakurajima-Tarumizu area was 1.61 (95% CI = 1.44–1.78) for men and 1.67 (95% CI = 1.39–1.95) for women while it was nearly equal to one in Kanoya city, which neighbors Tarumizu city but located at the further position from Mt. Sakurajima, and therefore has much smaller amounts of ashfall. Sakurajima-Tarumizu area had elevated SMRs for COPDs and acute respiratory diseases while Kanoya did not.Conclusions. Cristobalite is the most likely cause of the increased deaths from those chronic respiratory diseases since smoking is unlikely to explain the increased mortality of respiratory diseases among women since the proportion of smokers in Japanese women is less than 20%, and SPM levels in the Sakurajima-Tarumizu area were not high. Further studies seem warranted.
Paraoxonase Activity and Expression Is Modulated by Therapeutics in Experimental Rat Nonalcoholic Fatty Liver Disease
Authors: Hussein O. , Zidan J. , Abu Jabal K. , Shams I. , Szvalb S. , Grozovski M. , Bersudsky I. , Karry R. , Aviram M.
Published: March 2012

Objective. The objective of the present study is to investigate the effect of rosiglitazone, metformin, ezetimibe, and valsartan (alone or in combinations) on paraoxonase (PON) activity and PON-mRNA expression in nonalcoholic fatty liver disease (NAFLD).Methods. 54 Male Sprague–Dawley rats were divided to 9 groups: chow diet group (15 weeks); methionine-choline-deficient diet (MCDD) group (15 weeks); MCDD-treated groups for the last 6 weeks with either metformin (M), rosiglitazone (R), metformin plus rosiglitazone (M+R), ezetimibe (E), valsartan (V), or a combination of R+M+V or of R+M+V+E for a total period of 15 weeks.Results. PON activities in serum and liver were decreased in MCDD rats. PON activity in serum increased significantly in all treatment groups. PON activity in liver was also increased significantly, except only in groups R, E, V, R+M+V, and R+M+V+E. Liver PON3 mRNA expression increased significantly in groups R+M, E, V, R+M+V, and R+M+V+E whereas liver PON2 mRNA expression increased significantly in MCDD, R+M, E, V, R+M+V, and R+M+V+E.Conclusions. PON activities in serum and liver were decreased in NAFLD. Treatment with insulin sensitizers, ezetimibe, and valsartan increased PON activity and reduced oxidative stress both in serum and liver.
Effects of Aging Temperature on Moisture Absorption of Perforated GFRP
Authors: Eslami Shiva , Taheri-Behrooz Fathollah , Taheri Farid
Published: March 2012

This paper examines the effects of aging on the flexural stiffness and bending loading capacity of a perforated glass fiber-reinforced epoxy composite subjected to combined moisture and elevated temperature. Specimens, in the configuration of one-quarter of a perforated GFRP tube, were aged in 60% humidity and temperatures of 40, 60, and 80°C, respectively. Moisture absorptions of the specimens were measured during the aging process, and bending tests were conducted on the specimens after aging. The SEM images were also captured to further examine the effects of the moisture absorption on the aged specimens. The results indicated that the increase in the aging temperature reduced the diffusion coefficient, thus inducing more moisture absorption by the composite and in turn causing more reduction in composite’s flexural stiffness and bending capacity. Moreover, the ability of Fick’s equation for predicting the moisture absorption rate in such perforated thin-walled composite configuration at various moisture contents and temperatures was also assessed. A semiempirical equation was developed and proposed by which the reduction of the stiffness in the perforated aged GFRP structures could be predicted.
Detection of Quadruplex DNA by Gold Nanoparticles
Authors: Crouse Heather F. , Doudt Alex , Zerbe Cassie , Basu Swarna
Published: March 2012

Gold nanoparticles have been used as a probe to detect low (<10 ppb) concentrations of quadruplex DNA. These nanoparticles display a tendency to form aggregates in the presence of certain quadruplex forms, as observed via enhanced plasmon resonance light scattering (PRLS) signals. These nanoparticles showed differing degrees of interactions with different types of quadruplex and mixed sequences but no interaction with duplex DNA. Enhancement of PRLS signals greater than 50% was observed at nanomolar DNA concentration, and a lower limit of detection of 2.1 nM was established for three different quadruplex DNA sequences, including the thrombin-inhibiting single-stranded 15 mer aptamer DNA, d(GGTTGGTGTGGTTGG), and the double-stranded 12 mer DNA, d(G4T4G4). Two different sample preparation protocols were used for the PRLS experiments, and they yielded similar results.
Towards Point-of-Care Diagnostic and Staging Tools for Human African Trypanosomiaisis
Authors: Matovu Enock , Kazibwe Anne Juliet , Mugasa Claire Mack , Ndungu Joseph Mathu , Njiru Zablon Kithingi
Published: March 2012

Human African trypanosomiasis is a debilitating disease prevalent in rural sub-Saharan Africa. Control of this disease almost exclusively relies on chemotherapy that should be driven by accurate diagnosis, given the unacceptable toxicity of the few available drugs. Unfortunately, the available diagnostics are characterised by low sensitivities due to the inherent low parasitaemia in natural infections. Demonstration of the trypanosomes in body fluids, which is a prerequisite before treatment, often follows complex algorithms. In this paper, we review the available diagnostics and explore recent advances towards development of novel point-of-care diagnostic tests.
Orbital Burkitt’s Lymphoma: An Aggressive Presentation
Authors: Giuliari Gian Paolo , Sadaka Ama , Cortez Maria Angelica , Paniagua Antonina
Published: March 2012

Objective. To present the case of an aggressive orbital Burkitt’s lymphoma.Methods. Chart review.Case Presentation. A 24-year-old Haitian man came to our clinic complaining of rapidly progressive right eye proptosis. On examination, a large friable exophytic mass with necrotic areas and exudative/hemorrhagic secretions was noted protruding from his right orbit. A biopsy revealed the characteristic “starry-sky” appearance of a Burkitt lymphoma. The patient died shortly after due to complications from systemic involvement.Discussion. This case is meant to raise physicians’ awareness on the healthcare situation in some underdeveloped countries, emphasizing the importance of education in preventive medicine.
Antilisterial Activity of Nisin-Like Bacteriocin-ProducingLactococcus lactissubsp.lactisIsolated from Traditional Sardinian Dairy Products
Authors: Cosentino Sofia , Fadda Maria Elisabetta , Deplano Maura , Melis Roberta , Pomata Rita , Pisano Maria Barbara
Published: March 2012

With the aim of selecting LAB strains with antilisterial activity to be used as protective cultures to enhance the safety of dairy products, the antimicrobial properties of 117Lactococcus lactissubsp.lactisisolated from artisanal Sardinian dairy products were evaluated, and six strains were found to produce bacteriocin-like substances. The capacity of these strains to antagonizeListeria monocytogenesduring cocultivation in skimmed milk was evaluated, showing a reduction ofL. monocytogenescounts of approximately 4 log units compared to the positive control after 24 h of incubation. In order for a strain to be used as bioprotective culture, it should be carefully evaluated for the presence of virulence factors, to determine what potential risks might be involved in its use. None of the strains tested was found to produce biogenic amines or to possess haemolytic activity. In addition, all strains were sensitive to clinically important antibiotics such as ampicillin, tetracycline, and vancomycin. Our results suggest that these bac+ strains could be potentially applied in cheese manufacturing to control the growth ofL. monocytogenes.
Equilibrium, Thermodynamics, and Kinetic Sorption Studies for the Removal of Coomassie Brilliant Blue on Wheat Bran as a Low-Cost Adsorbent
Authors: Ata Sadia , Imran Din Muhammad , Rasool Atta , Qasim Imran , Ul Mohsin Ijaz
Published: March 2012

The sorption studies of coomassie brilliant blue (CBB) from aqueous solution have been carried out on wheat bran (WB). Coomassie brilliant blue on wheat bran was used to study the adsorption behavior under various parameters such as pH, dosage amount, and contact time. It was observed that under optimized conditions up to 95.70% dye could be removed from solution onto WB. Langmuir and Freundlich adsorption isotherms were used to elaborate the results. Freundlich model was found to be fitted well and favored multilayer adsorption. The Freundlich constants n and KF were determined as 0.53 and2.5×10−4. Thermodynamic parameters such asΔG,ΔH, andΔSstudied were taking into account, showed spontaneous and favorable reaction for coomassie brilliant blue on wheat bran. The maximum adsorption capacityqmwas found to be 6.410 mg/g. The investigations show that non treated WB is a low-cost adsorbent for the removal of dyes from textile industry effluents.