bluuebunny/crossref_metadata_2025 huggingface dataset:
Studying the association between methylenetetrahydrofolate reductase (MTHFR) 677 gene polymorphism, cardiovascular risk and lichen planus
Authors: Rashed Laila , Abdel Hay Rania , AlKaffas Marwa , Ali Shereen , Kadry Dina , Abdallah Sara
Published: May 2017

Background

There is a reported relation between hyperhomocysteinemia and lichen planus (LP). An increase in homocysteine (Hcy) and the risk of cardiovascular disease (CVD) in patients with methylenetetrahydrofolate reductase (MTHFR) mutation has been described.

Objective

To detect MTHFR (C677T) gene polymorphism, and to find its association with CVD risk, Hcy and folic acid levels in patients with LP.

Methods

This hospital‐based case‐control study included 110 patients with LP: 70 with cutaneous LP (CLP) and 40 with oral LP (OLP). A total of 120 age‐ and sex‐matched healthy subjects were used as controls. Three millilitre venous blood sample was taken for detection of MTHFR gene polymorphism by PCR‐RFLP technique and for measurement of the lipid profile. Hcy and folic acid were measured by ELISA. Hypertension was evaluated.

Results

There were significantly higher prevalence of hypertension with higher Hcy, triglycerides and cholesterol levels and lower folic acid and HDL levels among patients’ groups. Hypertension with higher Hcy and cholesterol levels together with lower folic acid and HDL levels have been found in OLP when compared to CLP. Patients showed a significant higher percentage of the MTHFR 677 TT genotype (P=.003) and of the MTHFR 677 T allele (P=.042) compared to controls. Moreover, there was a higher prevalence of MTHFR 677 T allele in patients with CLP.

Conclusion

MTHFR 677 gene polymorphism may be a risk factor for the development of the LP, and to predispose these patients to higher risk of CVD.
Strategies to Address Unmet Needs and Facilitate Return to Learn Guideline Adoption Following Concussion
Authors: Lyons Vivian H. , Moore Megan , Guiney Roxanne , Ayyagari Rajiv C. , Thompson Leah , Rivara Frederick P. , Fleming Robin , Crawley Deborah , Harper Dawn , Vavilala Monica S.
Published: May 2017

BACKGROUND

Many students do not receive return to learn (RTL) services upon return to academics following a concussion.

METHODS

Using a mixed‐methods approach, we conducted a survey of RTL practices and experiences in Washington State schools between January 2015 and June 2015. We then held a statewide summit of RTL stakeholders and used a modified Delphi process to develop a consensus‐based RTL implementation model and process.

RESULTS

Survey participants included 83 educators, 57 school nurses, 14 administrators, and 30 parents, representing 144 schools in rural and urban areas. Unmet need domains and recommendations identified were (1) a current lack of school policies; (2) barriers to providing or receiving accommodations; (3) wide variability in communication patterns; and (4) recommendations shared by all stakeholder groups (including desire for readily available best practices, development of a formal school RTL policy for easy adoption and more training). Using stakeholder input from RTL summit participants and survey responses, we developed an RTL implementation model and checklist for RTL guideline adoption.

CONCLUSIONS

Washington State children have unmet needs upon returning to public schools after concussion. The student‐centered RTL model and checklist for implementing RTL guidelines can help schools provide timely RTL services following concussion.
Pharmacokinetic and pharmacodynamic integration and modeling of acetylkitasamycin in swine for Clostridium perfringens
Authors: Nan J. , Hao H. , Xie S. , Pan Y. , Xi C. , Mao F. , Liu Z. , Huang L. , Yuan Z.
Published: May 2017

The aim of this study was to establish an integrated pharmacokinetic/pharmacodynamic (PK/PD) modeling approach of acetylkitasamycin for designing dosage regimens and decreasing the emergence of drug‐resistant bacteria. After oral administration of acetylkitasamycin to healthy and infected pigs at the dose of 50 mg/kg body weights (bw), a rapid and sensitive LC–MS/MS method was developed and validated for determining the concentration change of the major components of acetylkitasamycin and its possible metabolite kitasamycin in the intestinal samples taken from the T‐shape ileal cannula. The PK parameters, including the integrated peak concentration (Cmax), the time when the maximum concentration reached (Tmax) and the area under the concentration–time curve (AUC), were calculated by WinNonlin software. The minimum inhibitory concentration (MIC) of 60 C. perfringens strains was determined following CLSI guideline. The in vitro and ex vivo activities of acetylkitasamycin in intestinal tract against a pathogenic strain of C. perfringens type A (CPFK122995) were established by the killing curve. Our PK data showed that the integrated Cmax, Tmax, and AUC were 14.57–15.81 μg/ml, 0.78–2.52 hR, and 123.84–152.32 μg hr/ml, respectively. The PD data show that MIC50 and MIC90 of the 60 C. perfringens isolates were 3.85 and 26.45 μg/ml, respectively. The ex vivo growth inhibition data were fitted to the inhibitory sigmoid Emax equation to provide the values of AUC/MIC to produce bacteriostasis (4.84 hr), bactericidal activity (15.46 hr), and bacterial eradication (24.99 hr). A dosage regimen of 18.63 mg/kg bw every 12 hr could be sufficient in the prevention of C. perfringens infection. The therapeutic dosage regimen for C. perfringens infection was at the dose of 51.36 mg/kg bw every 12 hr for 3 days. In summary, the dosage regimen for the treatment of C. perfringens in pigs administered with acetylkitasamycin was designed using PK/PD integrate model. The designed dose regimen could to some extent decrease the risk for emergence of macrolide resistance.
Puccinia striiformis f. sp. tritici microRNA‐like RNA 1 (Pst‐milR1), an important pathogenicity factor of Pst, impairs wheat resistance to Pst by suppressing the wheat pathogenesis‐related 2 gene
Authors: Wang Bing , Sun Yanfei , Song Na , Zhao Mengxin , Liu Rui , Feng Hao , Wang Xiaojie , Kang Zhensheng
Published: May 2017

Small RNAs (sRNAs), an important type of pathogenicity factor, contribute to impairing host immune responses. However, little is known about sRNAs in Puccinia striiformis f. sp. tritici (Pst), one of the most destructive pathogens of wheat (Triticum aestivum L.). Here, we report a novel microRNA‐like RNA (milRNA) from Pst termed microRNA‐like RNA 1 (Pst‐milR1), which suppresses wheat defenses during wheat–Pst interactions.

We identified Pst‐milR1 as a novel milRNA in Pst. Biological prediction and co‐transformation showed that Pst‐milR1 takes part in cross‐kingdom RNA interference (RNAi) events by binding the wheat pathogenesis‐related 2 (PR2) gene.

Silencing of the Pst‐milR1 precursor resulted in increased wheat resistance to the virulent Pst isolate CYR31. PR2 knock‐down plants increased the susceptibility of wheat to the avirulent Pst isolate CYR23. This suggests that Pst‐milR1 represses the plant immune response by suppressing the expression of PR2.

Taking our findings together, we postulate that Pst‐milR1 is an important pathogenicity factor in Pst, which acts as an effector to suppress host immunity. Our results provide significant new insights into the pathogenicity of the stripe rust pathogen.
Progress toward openness, transparency, and reproducibility in cognitive neuroscience
Authors: Gilmore Rick O. , Diaz Michele T. , Wyble Brad A. , Yarkoni Tal
Published: May 2017

Accumulating evidence suggests that many findings in psychological science and cognitive neuroscience may prove difficult to reproduce; statistical power in brain imaging studies is low and has not improved recently; software errors in analysis tools are common and can go undetected for many years; and, a few large‐scale studies notwithstanding, open sharing of data, code, and materials remain the rare exception. At the same time, there is a renewed focus on reproducibility, transparency, and openness as essential core values in cognitive neuroscience. The emergence and rapid growth of data archives, meta‐analytic tools, software pipelines, and research groups devoted to improved methodology reflect this new sensibility. We review evidence that the field has begun to embrace new open research practices and illustrate how these can begin to address problems of reproducibility, statistical power, and transparency in ways that will ultimately accelerate discovery.
Population consequences of individual heterogeneity in life histories: overcompensation in response to harvesting of alternative reproductive tactics
Authors: Smallegange Isabel M. , Fernandes Rianne E. , Croll Jasper C.
Published: May 2017

Alternative reproductive tactics (ARTs) are examples of individual heterogeneity in which males adopt one of typically two alternative strategies to mate with females: males are either large, armed fighters or small, benign sneakers. ART expression is often conditionally determined, and variation in the expression of conditional ARTs due to genetic and/or environmental influences can greatly affect population composition and trajectory. For example, ecological feedback mechanisms resulting from strong density‐dependent competition over food have been suggested to explain the observation that the harvesting of scramblers (= sneakers) in closed populations of the bulb mite Rhizoglyphus robini did not result in an increase (expected from quantitative genetics theory) but decrease in fighter expression. Here, we exposed closed bulb mite populations to selective fighter or scrambler harvesting for 5–6 generations under abundant food (to halt ecological feedbacks through density‐dependence) to confirm predictions from quantitative genetics theory. However, we found no evolutionary shift in ART expression; rather, we observed an overcompensatory ecological response, whereby the number of fighters increased when we harvested them. Treatment effects on scrambler numbers could not be tested as there were too few in the experimental populations. Further experiments revealed that starved fighters preferentially killed immature males and immature fighters; possibly to reduce male‐male competition as e.g. immature fighters have not yet developed their lethal weaponry. If this is so, then harvesting adult fighters reduced the killing pressure on immature males in our experiment, which resulted in an overcompensatory number of immature fighters that matured as adults. Our results highlight the complexity of how individual heterogeneity in ARTs affects the ecological and evolutionary processes that determine population fluctuations.
Prevalence of Neural Tube Defects and the Impact of Prenatal Diagnosis in Three Districts of Beijing, China
Authors: Jin Lei , Jin Lei , Yu Jingru , Xu Yanjun , Liu Hui , Ren Aiguo
Published: May 2017

Background

The objectives of this study were to explore the prevalence of neural tube defects (NTDs) in three districts of Beijing, and to evaluate the impact of prenatal diagnosis on the prevalence.

Methods

Data were collected between 2006 and 2012 from the Beijing Birth Defects Surveillance System. P13 and P28 represent the prevalence of NTDs diagnosed from 13 weeks and 28 weeks of gestation, respectively, to 7 days after delivery. Populations were classified as household (permanent) and non‐household (non‐permanent) because differences exist in access to health care, education, and income, among others.

Results

The P13 of NTDs was 11.7 per 10 000 births in the three districts, which declined from 2006–12. In addition, the prevalence of NTDs in the non‐household population was 1.7‐fold higher than that among the household population. The P13 of anencephaly, spina bifida, and encephalocele were 5.3, 4.9, 1.6, respectively, per 10 000 births. The P28 of NTDs only represented 29.1% of P13, and this proportion decreased over the 7‐year period.

Conclusions

The prevalence of NTDs remains high in the three districts of Beijing, and the rate was higher in the non‐household than household population. The prevalence of birth defects would be under estimated by almost 70 per cent if the report time was set on 28 weeks’ gestation or later compared with report time on 13 weeks of gestation. It is better to set the report time earlier in birth defect surveillance in contemporary China.
Hydrogen peroxide produced by NADPH oxidase: a novel downstream signaling pathway in melatonin‐induced stress tolerance in Solanum lycopersicum
Authors: Gong Biao , Yan Yanyan , Wen Dan , Shi Qinghua
Published: May 2017

The beneficial effects of melatonin on abiotic stress have been demonstrated in several plants. However, little is known about the signal transduction pathway of melatonin involved in the plant stress response. Here, we manipulated the melatonin levels in tomato plants through a chemical approach. The roles of melatonin in stress tolerance were studied by assessing the symptoms, chlorophyll fluorescence and stress‐responsive gene expression. Moreover, both chemical and genetic approaches were used to study the roles of hydrogen peroxide (H2O2) in melatonin‐induced signal transduction in tomato plants. We found that melatonin activates NADPH oxidase (RBOH) to enhance H2O2 levels by reducing its S‐nitrosylation activity. Furthermore, melatonin‐induced H2O2 accumulation was accompanied by obtainable stress tolerance. Inhibition of RBOH or chemical scavenging of H2O2 significantly reduced the melatonin‐induced defense response, including reduced expression of several stress‐related genes (CDPK1, MAPK1, TSPMS, ERF4, HSP80 and ERD15) and reduced antioxidative enzyme activity (SOD, CAT and APX), which were responsible for the stress tolerance. Collectively, these results revealed a novel mechanism in which RBOH activity and H2O2 signaling are important components of the melatonin‐induced stress tolerance in tomato plants.
Why Have Policies Often Remained Symbolic? Understanding the Reasons for Decoupling between Policy and Practice
Authors: Lee Jusil
Published: May 2017

Why have policies that are unquestioningly accepted as appropriate remained symbolic? To answer the research question, I suggest two possible reasons for decoupling between policy and practice: the characteristics of normative pressure as “the weak enforcement mechanism of law” through the implementation stage and jurisdictions’ capacity to infuse the stories of success based on others’ use to their own day‐to‐day realities. In this article, I seek to reintroduce a seminal contribution of the early institutionalists by challenging the assumption that dimensions of adoption and implementation are synonymous or positively correlated. Empirical findings contribute to provide scholars and practitioners with a larger picture of policy diffusion and support the arguments by Nicholson‐Crotty and Carley that policy learning takes place based on policymakers’ assessment of both “policy actions” and “outcomes” in previously adopting jurisdictions.
Out of the shadow: Partners managing illness together
Authors: Nowakowski Alexandra C.H. , Sumerau J.E.
Published: May 2017

In this manuscript, we critically review existing studies of managing chronic illness within the context of intimate relationships to reveal future paths for this line of inquiry. Building on the combination of insights from previous studies and our own collaborative experiences managing chronic conditions together as relationship partners to one another, we outline some ways that intersectional analyses may broaden contemporary understandings of chronic illness management, and the ways people accomplish such management individually and collectively within varied concrete situations and social locations. Further, we reveal gaps in existing knowledge concerning, for example, sexual, gender, and relationship diversity and propose some ways that narrative and experience‐based analyses may begin to close these gaps. In conclusion, we outline a series of concrete directions for furthering study of chronic illness management within intimate relationships.
Disability at work: Understanding the impact of the ADA on the workplace
Authors: Durlak Paul R.
Published: May 2017

It has been more than 25 years since the Americans with Disabilities Act (ADA) was passed by Congress. Many supporters of the law hoped that it would improve the employment outcomes for people with a disability, yet many scholars argue that it has fallen short in achieving this goal. Such judgments of success or failure are typically offered with little regard for the complex relationship between law and social change. In this paper, I apply a socio‐legal perspective to scholarly research regarding the impact of the ADA on employment. Socio‐legal studies offer a variety of concepts and perspectives, which better capture the complexity of law's impact on social life, and the various paths through which it might have an impact on social change. From this perspective, studies tend to assume that ADA law will either impact social change directly or indirectly. I discuss the findings of both of these approaches and conclude with some directions for future research.
The salience of gender in return migration
Authors: Girma Hewan
Published: May 2017

Return migration warrants special attention as a growing trend in our current globalized environment wherein migration can no longer be assumed to be a one‐way journey. As studies of return migration are burgeoning, this article argues for the salience of taking socially constructed ideas of gender as a central analytical factor in order to understand the complexities of human movement. It is imperative to take up gender both as a category of analysis and as a means to expand our theoretical understanding of migration. The process of return migration is overshadowed by gendered ideologies both in the home and in the host nation, as migrants leave and return to gendered societies. Through a review of recent literature, this paper will argue the multifaceted benefits of incorporating a gendered perspective in return migration research.
Measuring the scales of segregation: looking at the residential separation of White British and other schoolchildren in England using a multilevel index of dissimilarity
Authors: Harris Richard
Published: May 2017

Within the segregation literature there has been a movement away from measuring ethnic segregation at a single scale, using traditional indices, to instead treating segregation as a multiscale phenomenon about which measurement at a range of scales will shed knowledge. Amongst the contributions, several authors have promoted multilevel modelling as a way of looking at segregation at multiple scales of a geographical hierarchy, estimating the micro‐, meso‐ and macro‐effects of segregation simultaneously. This paper takes the approach forward by outlining a multilevel index of dissimilarity that combines the advantages of using a widely understood index with a means to identify scale effects in a way that is computationally fast to estimate with freely available software to do so. To demonstrate the method, a case study is made looking at the residential separation of White British pupils from six other ethnic groups in England in 2011. It examines a claim made by the Casey Review into opportunity and integration that schoolchildren are more residentially segregated than the population at large. The results suggest that schoolchildren were indeed more residentially divided but comparison with earlier data and the general uplift in the scales at which patterns of segregation are evident suggest a trend of decreasing segregation overall and the spreading out of ‘minority’ groups.
‘The ice edge is lost … nature moved it’: mapping ice as state practice in the Canadian and Norwegian North
Authors: Steinberg Philip , Kristoffersen Berit
Published: May 2017

This paper explores how ‘ice’ is woven into the spaces and practices of the state in Norway and Canada and, specifically, how representations of the sea ice edge become political agents in that process. We focus in particular on how these states have used science to ‘map’ sea ice – both graphically and legally – over the past decades. This culminated with two maps produced in 2015, a Norwegian map that moved the Arctic sea‐ice edge 70 km northward and a Canadian map that moved it 200 km southward. Using the maps and their genealogies to explore how designations of sea ice are entangled with political objectives (oil drilling in Norway, sovereignty claims in Canada), we place the maps within the more general tendency of states to assign fixed categories to portions of the earth's surface and define distinct lines between them. We propose that the production of static ontologies through cartographic representations becomes particularly problematic in an icy environment of extraordinary temporal and spatial dynamism, where complex ocean–atmospheric processes and their biogeographic impacts are reduced to lines on a map.
DANCING AROUND THE CAUSAL JOINT: CHALLENGING THE THEOLOGICAL TURN IN DIVINE ACTION THEORIES
Authors: Ritchie Sarah Lane
Published: May 2017

Recent years have seen a shift in divine action debates. Turning from noninterventionist, incompatibilist causal joint models, representatives of a “theological turn” in divine action have questioned the metaphysical assumptions of approaches seeking indeterministic aspects of nature wherein God might act. Various versions of theistic naturalism (such as Thomism, panentheistic naturalism, and pneumatological naturalism) offer specific theological frameworks that reimagine the basic God–world relationship. But do these explicitly theological approaches to divine action take scientific knowledge and methodology seriously enough? And do such approaches adequately address the problem of how uncreated, immaterial realities could affect physical, material processes? This article examines various features of the theological turn in divine action—recognizing it as a welcome step in science and religion, while challenging its current adequacy.
TELESCOPE + MIRROR = REFLECTIONS ON THE COSMOS: UMBERTO ECO AND THE IMAGE OF RELIGION
Authors: Peters Benjamin John
Published: May 2017

Umberto Eco argues that a mirror image is not a sign. At best it is a double, a thing that ceases to be once the reflected object is removed. Harry Mulisch narratively suggests that mirror images function metaphorically as gateways between human suffering and the divine. And interestingly, science employs mirrors and mirror images both to turn our gaze upwards and to show us reflections of our place in the cosmos. Tying together Eco's notion of the double, Mulisch's insistence that mirror images reflect humanity's construction of the divine, and the Giant Magellan Telescope Project's cosmic images, it is my contention that modern, telescopic mirror images are much more than snapshots of the cosmos. They are constructions of human and divine meaning that—signifying—pose the question, what is reflected: the cosmos or humanity?
SYSTEMS BIOLOGY AND PREDICTIVE NEUROSCIENCE: A DOUBLE HELICAL APPROACH
Authors: Wiseman Harris
Published: May 2017

This article explores the overlap between systems biology and predictive neuroscience, placing them in their larger context, the contemporary trend of bioinformatic convergence across the sciences. These two domains overlap with respect to their interest in data accumulation and data integration; their reliance on computational statistical correlation; and their translational goals, that is, producing practical fruits and applications from the interscientific cross‐pollination that contemporary data‐integrative approaches make possible. The interventions that such translational conversations generate are medical and social in nature, and are aimed at both prevention (through prediction) and treatment. It will be argued that such approaches, socially and medically applied, contain potential for conveying both agency‐enhancing and agency‐diminishing social messages. The article concludes with a call to balance the overwhelmingly quantitative focus characteristic of predictive neuroscience with more qualitative empirical methodologies. This would represent a double helical approach.
EPIGENETICS, REPRESENTATION, AND SOCIETY
Authors: Gadjev Ilya
Published: May 2017

In recent decades, advances in the life sciences have created an unprecedentedly detailed picture of heredity and the formation of the phenotype where clusters of simplistic reductionist and deterministic views and interpretations have begun to lose ground to more complex and holistic notions. The developments in gene regulation and epigenetics have become a vivid emblem of the ongoing ‘softening’ of heredity. Despite this headway, the outlook and rhetoric widely popular in the twentieth century favoring the ‘gene’ in the ‘gene↔genetic plasticity↔phenotype↔environment’ tetrad have not been successfully tackled but continue to exist in parallel with a new, equally monochromatic, viewpoint championing genetic plasticity. An examination of epigenetics and its presentation in the public sphere, open to a conversation with the social disciplines and philosophy, could address this dichotomy and contribute to the discourse. This article outlines key biological aspects of epigenetics and discusses the language, presentation and wider resonance of this field of life science research.
THE EXPLORATION OF ECOSPACE: EXTENDING OR SUPPLEMENTING THE NEO‐DARWINIAN PARADIGM?
Authors: Gregersen Niels Henrik
Published: May 2017

The neo‐Darwinian paradigm, focusing on natural selection of genes responsible for differential adaption, provides the foundation for explaining evolutionary processes. The modern synthesis is broader, however, focusing on organisms rather than on gene transmissions per se. Yet, strands of current biology argue for further supplementation of Darwinian theory, pointing to nonbiotic drivers of evolutionary development, for example, self‐organization of physical structures, and the interaction between individual organisms, groups of organisms, and their nonbiotic environments. According to niche construction theory, when organisms and groups develop, they not only adapt to their environments but modify their environments, creating new habitats for later generations. Insofar as ecological niches persist beyond the lifecycle of individual organisms, an ecological inheritance system exists alongside genetic inheritance. Such ecological structures may even facilitate the development of a cultural inheritance system, as we see in humans. The article discusses theological perspectives of such new developments within holistic biology.
On the fourth moment of Hecke–Maass forms and the random wave conjecture
Authors: Buttcane Jack , Khan Rizwanur
Published: May 2017

Conditionally on the generalized Lindelöf hypothesis, we obtain an asymptotic for the fourth moment of Hecke–Maass cusp forms of large Laplacian eigenvalue for the full modular group. This lends support to the random wave conjecture.
Multiscale Mechanical Evaluation of Human Supraspinatus Tendon Under Shear Loading After Glycosaminoglycan Reduction
Authors: Fang Fei , Lake Spencer P.
Published: May 2017

Proteoglycans (PGs) are broadly distributed within many soft tissues and, among other roles, often contribute to mechanical properties. Although PGs, consisting of a core protein and glycosaminoglycan (GAG) sidechains, were once hypothesized to regulate stress/strain transfer between collagen fibrils and help support load in tendon, several studies have reported no changes to tensile mechanics after GAG depletion. Since GAGs are known to help sustain nontensile loading in other tissues, we hypothesized that GAGs might help support shear loading in human supraspinatus tendon (SST), a commonly injured tendon which functions in a complex multiaxial loading environment. Therefore, the objective of this study was to determine whether GAGs contribute to the response of SST to shear, specifically in terms of multiscale mechanical properties and mechanisms of microscale matrix deformation. Results showed that chondroitinase ABC (ChABC) treatment digested GAGs in SST while not disrupting collagen fibers. Peak and equilibrium shear stresses decreased only slightly after ChABC treatment and were not significantly different from pretreatment values. Reduced stress ratios were computed and shown to be slightly greater after ChABC treatment compared to phosphate-buffered saline (PBS) incubation without enzyme, suggesting that these relatively small changes in stress values were not due strictly to tissue swelling. Microscale deformations were also not different after ChABC treatment. This study demonstrates that GAGs possibly play a minor role in contributing to the mechanical behavior of SST in shear, but are not a key tissue constituent to regulate shear mechanics.
Design and Validation of a Biosensor Implantation Capsule Robot
Authors: Xie Wanchuan , Lewis Weston M. , Kaser Jared , Ross Welch C. , Li Pengbo , Nelson Carl A. , Kothari Vishal , Terry Benjamin S.
Published: May 2017

We have proposed a long-term, noninvasive, nonrestrictive method of delivering and implanting a biosensor within the body via a swallowable implantation capsule robot (ICR). The design and preliminary validation of the ICR’s primary subsystem—the sensor deployment system—is discussed and evidence is provided for major design choices. The purpose of the sensor deployment system is to adhere a small biosensor to the mucosa of the intestine long-term, and the modality was inspired by tapeworms and other organisms that employ a strategy of mechanical adhesion to soft tissue via the combined use of hooks or needles and suckers. Testing was performed to refine the design of the suction and needle attachment as well as the sensor ejection features of the ICR. An experiment was conducted in which needle sharpness, needle length, and vacuum volume were varied, and no statistically significant difference was observed. Finally, preliminary testing, coupled with prior work within a live porcine model, provided evidence that this is a promising approach for implanting a biosensor within the small intestine.
Symplectic Analysis for Wrinkles: A Case Study of Layered Neo-Hookean Structures
Authors: Zhang Teng
Published: May 2017

Wrinkles are widely found in natural and engineering structures, ranging from skins to stretchable electronics. However, it is nontrivial to predict wrinkles, especially for complicated structures, such as multilayer or gradient structures. Here, we establish a symplectic analysis framework for the wrinkles and apply it to layered neo-Hookean structures. The symplectic structure enables us to accurately and efficiently solve the eigenvalue problems of wrinkles via the extended Wittrick–Williams (w–W) algorithm. The symplectic analysis is able to exactly predict wrinkles in bi- and triple-layer structures, compared with the benchmark results and finite element simulations. Our findings also shed light on the formation of hierarchical wrinkles
Solving Nongray Boltzmann Transport Equation in Gallium Nitride
Authors: Vallabhaneni Ajit K. , Chen Liang , Gupta Man P. , Kumar Satish
Published: May 2017

Several studies have validated that diffusive Fourier model is inadequate to model thermal transport at submicron length scales. Hence, Boltzmann transport equation (BTE) is being utilized to improve thermal predictions in electronic devices, where ballistic effects dominate. In this work, we investigated the steady-state thermal transport in a gallium nitride (GaN) film using the BTE. The phonon properties of GaN for BTE simulations are calculated from first principles—density functional theory (DFT). Despite parallelization, solving the BTE is quite expensive and requires significant computational resources. Here, we propose two methods to accelerate the process of solving the BTE without significant loss of accuracy in temperature prediction. The first one is to use the Fourier model away from the hot-spot in the device where ballistic effects can be neglected and then couple it with a BTE model for the region close to hot-spot. The second method is to accelerate the BTE model itself by using an adaptive model which is faster to solve as BTE for phonon modes with low Knudsen number is replaced with a Fourier like equation. Both these methods involve choosing a cutoff parameter based on the phonon mean free path (mfp). For a GaN-based device considered in the present work, the first method decreases the computational time by about 70%, whereas the adaptive method reduces it by 60% compared to the case where full BTE is solved across the entire domain. Using both the methods together reduces the overall computational time by more than 85%. The methods proposed here are general and can be used for any material. These approaches are quite valuable for multiscale thermal modeling in solving device level problems at a faster pace without a significant loss of accuracy.
Thermoeconomic Optimization and Comparison of Plate-Fin Heat Exchangers Using Louver, Offset Strip, Triangular and Rectangular Fins Applied in 200 kW Microturbines
Authors: Maghsoudi Peyman , Sadeghi Sadegh , Hanafizadeh Pedram
Published: May 2017

In this paper, four types of plate-fin heat exchangers applied in 200 kW microturbines are investigated. Multi-objective optimization algorithm, NSGA-II (nondominated sorting genetic algorithm (GA)), is employed to maximize the efficiency of the recuperator and minimize its total cost, simultaneously. Feasible ranges of pressure drop, Reynolds number, and recuperator efficiency are obtained according to a penalty function. The optimizations are conducted for rectangular fin, triangular fin, louver fin, and offset strip fin recuperators with cross and counter flow arrangements. The results of each optimization problem are presented as a set of designs, called “Pareto-optimal solutions.” Afterward, for the designs, cycle efficiency and net present value (NPV) are compared based on technical and economic criteria, respectively. Maximum cycle efficiency occurring in a recuperator with louver fin and counter flow arrangement is found to be 38.17%. Finally, the optimum designs are compared based on nondominated sorting concept leading to the optimal solutions.
Selection and Characterization of Green Propellants for Micro-Resistojets
Authors: Guerrieri Daduí C. , Silva Marsil A. C. , Cervone Angelo , Gill Eberhard
Published: May 2017

The number of launches of nano- and pico-satellites has significantly increased over the past decade. Miniaturized subsystems, such as micropropulsion, for these classes of spacecraft are rapidly evolving and, in particular, micro-resistojets have shown great potential of applicability. One of the key points to address in the development of such devices is the propellants selection, since it directly influences the performance. This paper presents a methodology for the selection and characterization of fluids that are suitable for use as propellants in two micro-resistojet concepts: vaporizing liquid micro-resistojet (VLM) and the low-pressure micro-resistojet (LPM). In these concepts, the propellant is heated by a nonchemical energy source, in this case an electrical resistance. In total 95 fluids have been investigated including conventional and unconventional propellants. A feasibility assessment step is carried out following a trade-off using a combination of the analytical hierarchy process (AHP) and the Pugh matrix. A final list of nine best-scoring candidates has been analyzed in depth with respect to the thermal characteristics involved in the process, performance parameters, and safety issues. For both concepts, water has been recognized as a very promising candidate along with other substances such as ammonia and methanol.
On Regularization in Design for Reliability for Nonlinear Planar Beam-Type Resonators
Authors: Tripathi Astitva , Bajaj Anil K.
Published: May 2017

Robustness is a highly desirable quality in microelectromechanical systems (MEMS). Sensors and resonators operating on nonlinear dynamic principles such as internal resonances are no exception to this, and in addition, when nonlinear dynamic phenomena are used to enhance device sensitivity, their requirements for robustness may even be greater. This work discusses two aspects as they relate to the robustness and performance of nonlinear resonators. In the first aspect, different resonator designs are compared to find which among them have a better capacity to deliver reliable and reproducible performance in face of variations from the nominal design due to manufacturing process uncertainties/tolerances. The second aspect attempts to identify the inherent topological features that, if present in a resonator, enhance its robustness. Thus, the first part of this work is concerned with uncertainty analysis of several candidate nonlinear resonators operating under the principle of 1:2 internal resonance and obtained via a hierarchical optimization method introduced by the authors. The second part discusses specific changes to the computational design process that can be made so as to enhance the robustness and reliability of the candidate resonators.
Horseshoe bats and Old World leaf-nosed bats have two discrete types of pinna motions
Authors: Yin Xiaoyan , Qiu Peiwen , Yang Lili , Müller Rolf
Published: May 2017

Horseshoe bats (Rhinolophidae) and the related Old World leaf-nosed bats (Hipposideridae) both show conspicuous pinna motions as part of their biosonar behaviors. In the current work, the kinematics of these motions in one species from each family (Rhinolophus ferrumequinum and Hipposideros armiger) has been analyzed quantitatively using three-dimensional tracking of landmarks placed on the pinna. The pinna motions that were observed in both species fell into two categories: In “rigid rotations” motions the geometry of the pinna was preserved and only its orientation in space was altered. In “open–close motions” the geometry of the pinna was changed which was evident in a change of the distances between the landmark points. A linear discriminant analysis showed that motions from both categories could be separated without any overlap in the analyzed data set. Hence, bats from both species have two separate types of pinna motions with apparently no transitions between them. The deformations associated with open–close pinna motions in Hipposideros armiger were found to be substantially larger compared to the wavelength associated with the largest pulse energy than in Rhinolophus ferrumequinum (137% vs 99%). The role of the two different motions in the biosonar behaviors of the animals remains to be determined.
Shutting down innate immune responses during fertilization
Authors: Foley John F.
Published: May 2017

The inflammasome component NLRP14 inhibits the nucleic acid sensing pathway during fertilization.
New connections: Treating fragile X syndrome
Authors: Ferrarelli Leslie K.
Published: May 2017

An in vivo drug screen can identify inhibitors of the signaling pathway that is activated in fragile X syndrome.
Genetic Determinants of the Pharmacokinetic Variability of Rifampin in Malawian Adults with Pulmonary Tuberculosis
Authors: Sloan Derek J. , McCallum Andrew D. , Schipani Alessandro , Egan Deirdre , Mwandumba Henry C. , Ward Steve A. , Waterhouse David , Banda Gertrude , Allain Theresa J. , Owen Andrew , Khoo Saye H. , Davies Geraint R.
Published: May 2017

Variable exposure to antituberculosis (TB) drugs, partially driven by genetic factors, may be associated with poor clinical outcomes. Previous studies have suggested an influence of the
SLCO1B1
locus on the plasma area under the concentration-time curve (AUC) of rifampin. We evaluated the contribution of single nucleotide polymorphisms (SNPs) in
SLCO1B1
and other candidate genes (
AADAC
and
CES-1
) to interindividual pharmacokinetic variability in Malawi. A total of 174 adults with pulmonary TB underwent sampling of plasma rifampin concentrations at 2 and 6 h postdose. Data from a prior cohort of 47 intensively sampled, similar patients from the same setting were available to support population pharmacokinetic model development in NONMEM v7.2, using a two-stage strategy to improve information during the absorption phase. In contrast to recent studies in South Africa and Uganda, SNPs in
SLCO1B1
did not explain variability in AUC
0–∞
of rifampin. No pharmacokinetic associations were identified with
AADAC
or
CES-1
SNPs, which were rare in the Malawian population. Pharmacogenetic determinants of rifampin exposure may vary between African populations.
SLCO1B1
and other novel candidate genes, as well as nongenetic sources of interindividual variability, should be further explored in geographically diverse, adequately powered cohorts.
Esx Systems and the Mycobacterial Cell Envelope: What's the Connection?
Authors: Bosserman Rachel E. , Champion Patricia A.
Published: May 2017

Mycobacterial 6-kDa early secreted antigenic target (ESAT-6) system (ESX) exporters transport proteins across the cytoplasmic membrane. Many proteins transported by ESX systems are then translocated across the mycobacterial cell envelope and secreted from the cell. Although the mechanism underlying protein transport across the mycolate outer membrane remains elusive, the ESX systems are closely connected with and localize to the cell envelope. Links between ESX-associated proteins, cell wall synthesis, and the maintenance of cell envelope integrity have been reported. Genes encoding the ESX systems and those required for biosynthesis of the mycobacterial envelope are coregulated. Here, we review the interplay between ESX systems and the mycobacterial cell envelope.
The Response to 2-Aminoacrylate Differs in Escherichia coli and Salmonella enterica, despite Shared Metabolic Components
Authors: Borchert Andrew J. , Downs Diana M.
Published: May 2017

The metabolic network of an organism includes the sum total of the biochemical reactions present. In microbes, this network has an impeccable ability to sense and respond to perturbations caused by internal or external stimuli. The metabolic potential (i.e., network structure) of an organism is often drawn from the genome sequence, based on the presence of enzymes deemed to indicate specific pathways.
Escherichia coli
and
Salmonella enterica
are members of the
Enterobacteriaceae
family of Gram-negative bacteria that share the majority of their metabolic components and regulatory machinery as the “core genome.” In
S. enterica
, the ability of the enamine intermediate 2-aminoacrylate (2AA) to inactivate a number of pyridoxal 5′-phosphate (PLP)-dependent enzymes has been established
in vivo
. In this study, 2AA metabolism and the consequences of its accumulation were investigated in
E. coli
. The data showed that despite the conservation of all relevant enzymes,
S. enterica
and
E. coli
differed in both the generation and detrimental consequences of 2AA. In total, these findings suggest that the structure of the metabolic network surrounding the generation and response to endogenous 2AA stress differs between
S. enterica
and
E. coli
.

IMPORTANCE
This work compared the metabolic networks surrounding the endogenous stressor 2-aminoacrylate in two closely related members of the
Enterobacteriaceae
. The data showed that despite the conservation of all relevant enzymes in this metabolic node, the two closely related organisms diverged in their metabolic network structures. This work highlights how a set of conserved components can generate distinct network architectures and how this can impact the physiology of an organism. This work defines a model to expand our understanding of the 2-aminoacrylate stress response and the differences in metabolic structures and cellular milieus between
S. enterica
and
E. coli
.
A Mutation in the Bacillus subtilis rsbU Gene That Limits RNA Synthesis during Sporulation
Authors: Rothstein David M. , Lazinski David , Osburne Marcia S. , Sonenshein Abraham L.
Published: May 2017

Mutants of
Bacillis subtilis
that are temperature sensitive for RNA synthesis during sporulation were isolated after selection with a
32
P suicide agent. Whole-genome sequencing revealed that two of the mutants carried an identical lesion in the
rsbU
gene, which encodes a phosphatase that indirectly activates SigB, the stress-responsive RNA polymerase sigma factor. The mutation appeared to cause RsbU to be hyperactive, because the mutants were more resistant than the parent strain to ethanol stress. In support of this hypothesis, pseudorevertants that regained wild-type levels of sporulation at high temperature had secondary mutations that prevented expression of the mutant
rsbU
gene. The properties of these RsbU mutants support the idea that activation of SigB diminishes the bacterium's ability to sporulate.

IMPORTANCE
Most bacterial species encode multiple RNA polymerase promoter recognition subunits (sigma factors). Each sigma factor directs RNA polymerase to different sets of genes; each gene set typically encodes proteins important for responses to specific environmental conditions, such as changes in temperature, salt concentration, and nutrient availability. A selection for mutants of
Bacillus subtilis
that are temperature sensitive for RNA synthesis during sporulation unexpectedly yielded strains with a point mutation in
rsbU
, a gene that encodes a protein that normally activates sigma factor B (SigB) under conditions of salt stress. The mutation appears to cause RsbU, and therefore SigB, to be active inappropriately, thereby inhibiting, directly or indirectly, the ability of the cells to transcribe sporulation genes.
Three-dimensional solvsolitons and the minimality of the corresponding submanifolds
Authors: Hashinaga Takahiro , Tamaru Hiroshi
Published: May 2017

In this paper, we define the corresponding submanifolds to left-invariant Riemannian metrics on Lie groups, and study the following question: does a distinguished left-invariant Riemannian metric on a Lie group correspond to a distinguished submanifold? As a result, we prove that the solvsolitons on three-dimensional simply-connected solvable Lie groups are completely characterized by the minimality of the corresponding submanifolds.
Attitude algorithm and initial alignment method for SINS applied in short-range aircraft
Authors: Zhang Rong-Hui , He Zhao-Cheng , You Feng , Chen Bo
Published: May 2017

This paper presents an attitude solution algorithm based on the Micro-Electro-Mechanical System and quaternion method. We completed the numerical calculation and engineering practice by adopting fourth-order Runge–Kutta algorithm in the digital signal processor. The state space mathematical model of initial alignment in static base was established, and the initial alignment method based on Kalman filter was proposed. Based on the hardware in the loop simulation platform, the short-range flight simulation test and the actual flight test were carried out. The results show that the error of pitch, yaw and roll angle is fast convergent, and the fitting rate between flight simulation and flight test is more than 85%.
MHC2NNZ: A novel peptide binding prediction approach for HLA DQ molecules
Authors: Xie Jiang , Zeng Xu , Lu Dongfang , Liu Zhixiang , Wang Jiao
Published: May 2017

The major histocompatibility complex class II (MHC-II) molecule plays a crucial role in immunology. Computational prediction of MHC-II binding peptides can help researchers understand the mechanism of immune systems and design vaccines. Most of the prediction algorithms for MHC-II to date have made large efforts in human leukocyte antigen (HLA, the name of MHC in Human) molecules encoded in the DR locus. However, HLA DQ molecules are equally important and have only been made less progress because it is more difficult to handle them experimentally. In this study, we propose an artificial neural network-based approach called MHC2NNZ to predict peptides binding to HLA DQ molecules. Unlike previous artificial neural network-based methods, MHC2NNZ not only considers sequence similarity features but also captures the chemical and physical properties, and a novel method incorporating these properties is proposed to represent peptide flanking regions (PFR). Furthermore, MHC2NNZ improves the prediction accuracy by combining with amino acid preference at more specific positions of the peptides binding core. By evaluating on 3549 peptides binding to six most frequent HLA DQ molecules, MHC2NNZ is demonstrated to outperform other state-of-the-art MHC-II prediction methods.