bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibitory effect of camel milk on Cronobacter sakazakii
Authors: Abusheliabi Aisha , Al‐Rumaithi Hind O. , Olaimat Amin N. , Al‐Nabulsi Anas A. , Osaili Tareq , Shaker Reyad , Ayyash Mutamed M.
Published: January 2017

The objective of this study was to investigate the behavior of Cronobacter sakazakii in raw and pasteurized camel milk compared with bovine milk at different incubation temperatures. Pasteurized and raw camel milk was inoculated with a cocktail of two strains of C. sakazakii and incubated at 10°C, 25°C, and 37°C to be sampled at 0, 2, 4, 8, and 24 hr. Pasteurized bovine milk was treated similarly and used as a control. Raw and pasteurized camel milk showed more inhibitory effect against C. sakazakii at 25°C than 37°C while there was no effect at 10°C. The inhibition ranged from 0.40 to 1.42 CFU/ml and 0.61 to 1.6 CFU/ml at 25°C, and from 0.40 to 0.92 CFU/ml and 0.40 to 0.80 CFU/ml at 37°C in pasteurized and raw camel milk after 24 hr, respectively, compared with bovine milk. Moreover, the inhibitory effect of pasteurized camel milk against C. sakazakii was more than raw camel milk after 24 hr at the different incubation temperatures which may approve that the natural antimicrobial proteins in camel milk were resistant to pasteurization temperature.

Practical application

Due to the association of Cronobacter sakazakii with powdered infant formula (PIF), controlling methods, therefore, are highly demanded by PIF manufacturers. The inhibitory activities of camel milk against C. sakazakii and nutritional value make camel milk an outstanding candidate to substitute bovine milk as a base of PIF.
Plant phosphatidylinositol‐specific phospholipase C at the center of plant innate immunity
Authors: Abd‐El‐Haliem Ahmed M. , Joosten Matthieu H.A.J.
Published: January 2017

Understanding plant resistance to pathogenic microbes requires detailed information on the molecular mechanisms controlling the execution of plant innate immune responses. A growing body of evidence places phosphoinositide‐specific phospholipase C (PI‐PLC) enzymes immediately downstream of activated immune receptors, well upstream of the initiation of early defense responses. An increase of the cytoplasmic levels of free Ca2+, lowering of the intercellular pH and the oxidative burst are a few examples of such responses and these are regulated by PI‐PLCs. Consequently, PI‐PLC activation represents an early primary signaling switch between elicitation and response involving the controlled hydrolysis of essential signaling phospholipids, thereby simultaneously generating lipid and non‐lipid second messenger molecules required for a swift cellular defense response. Here, we elaborate on the signals generated by PI‐PLCs and their respective downstream effects, while providing an inventory of different types of evidence describing the involvement of PI‐PLCs in various aspects of plant immunity. We project the discussed information into a model describing the cellular events occurring after the activation of plant immune receptors. With this review we aim to provide new insights supporting future research on plant PI‐PLCs and the development of plants with improved resistance.
Labor Intervention and Outcomes in Women Who Are Nulliparous and Obese: Comparison of Nurse‐Midwife to Obstetrician Intrapartum Care
Authors: Carlson Nicole S. , Corwin Elizabeth J. , Lowe Nancy K.
Published: January 2017

Background

Women who are obese have slower labors than women of normal weight, and show reduced response to interventions designed to speed labor progress like oxytocin augmentation and artificial rupture of membranes. The optimal labor management for these women has not been described.

Methods

This retrospective cohort study compared 2 propensity score‐matched groups of women (N = 360) who were healthy, nulliparous, spontaneously laboring, and obese (body mass index ≥ 30 kg/m2). Labors were managed by either a certified nurse‐midwife (CNM) or an obstetrician at one hospital from 2005 through 2012. Comparisons were made on a range of labor processes and outcomes.

Results

Women who were obese and cared for in labor by CNMs were 87.0% less likely to have operative vaginal birth (adjusted odds ratio [aOR], 0.15; 95% confidence interval [CI], 0.06‐0.41) and 76.3% less likely to have third‐ or fourth‐degree perineal lacerations (aOR, 0.31; 95% CI, 0.13‐0.79) compared to a matched group of women who were obese and had similarly sized neonates but who were cared for by obstetricians. The rates of unplanned cesarean birth, postpartum hemorrhage, maternal intrapartum fever, and neonatal intensive care unit admission were similar between groups. CNM patients were significantly less likely than patients of obstetricians to have labor anesthesia, synthetic oxytocin augmentation, or intrauterine pressure catheters. By contrast, CNM patients were significantly more likely than patients of obstetricians to use physiologic labor interventions, including intermittent fetal monitoring, ambulation, and hydrotherapy.

Discussion

In women with spontaneous labor onset who were healthy, obese, and nulliparous, watchful waiting and use of physiologic labor interventions, characterizing CNM intrapartum care, were associated with outcomes that were similar to, or better than, those of women who were obese and exposed to more high‐technology interventions characterizing intrapartum care by obstetricians. In women who were obese, physiologic labor interventions were safe for both mothers and neonates.
Cultural Sensitivity Among Clinical Nurses: A Descriptive Study
Authors: Yilmaz Medine , Toksoy Serap , Direk Zübeyde Denizci , Bezirgan Selma , Boylu Münevver
Published: January 2017

Purpose

The purpose of this study was to investigate the cultural sensitivity of nurses working in rural and urban hospitals in Turkey.

Design and Methods

The sampling of this descriptive and correlational study was composed of only 516 clinical nurses working in inpatient clinics. The data collection tools were the Socio‐Demographic Questionnaire and the Intercultural Sensitivity Scale.

Findings

A majority of the participating nurses experienced culture‐related problems. Intercultural Sensitivity Scale results were partially high. The nurses had more problems in areas related to language barriers, patients’ education level, and health perception about disease and religious beliefs when providing health care. Participants who were female, had an undergraduate or graduate education, had received in‐service education on cultural care, or had taken transcultural nursing coursework obtained higher scores on the Intercultural Sensitivity Scale and its Interaction Engagement subscale. The cultural sensitivity level was 84.01 ± 9.1 (range = 43–107). The proportion of nurses who had received no in‐service education was very high. They wanted to participate in an education program to gain better understanding of the culture of the society in which they lived.

Conclusions

The results of the present study demonstrated that nurses should be prepared in cultural sensitivity and cultural competence.

Clinical Relevance

Continuing education and formal courses on cultural sensitivity for nursing professionals are essential for optimal health outcomes. Thus, inequalities in health could be prevented and the quality of health care could be improved.
Lessons Learned From a Practice‐Based, Multisite Intervention Study With Nurse Participants
Authors: Friese Christopher R. , Mendelsohn‐Victor Kari , Ginex Pamela , McMahon Carol M. , Fauer Alex J. , McCullagh Marjorie C.
Published: January 2017

Purpose

To identify challenges and solutions to the efficient conduct of a multisite, practice‐based randomized controlled trial to improve nurses’ adherence to personal protective equipment use in ambulatory oncology settings.

Design

The Drug Exposure Feedback and Education for Nurses’ Safety (DEFENS) study is a clustered, randomized, controlled trial. Participating sites are randomized to Web‐based feedback on hazardous drug exposures in the sites plus tailored messages to address barriers versus a control intervention of a Web‐based continuing education video.

Approach

The study principal investigator, the study coordinator, and two site leaders identified challenges to study implementation and potential solutions, plus potential methods to prevent logistical challenges in future studies.

Findings

Noteworthy challenges included variation in human subjects’ protection policies, grants and contracts budgeting, infrastructure for nursing‐led research, and information technology variation. Successful strategies included scheduled Web conferences, site‐based study champions, site visits by the principal investigator, and centrally based document preparation. Strategies to improve efficiency in future studies include early and continued engagement with contract personnel in sites, and proposed changes to the common rule concerning human subjects. The DEFENS study successfully recruited 393 nurses across 12 sites. To date, 369 have completed surveys and 174 nurses have viewed educational materials.

Conclusions

Multisite studies of nursing personnel are rare and challenging to the existing infrastructure. These barriers can be overcome with strong engagement and planning.

Clinical Relevance

Leadership engagement, onsite staff support, and continuous communication can facilitate successful recruitment to a workplace‐based randomized, controlled behavioral trial.
Developing Evidence–based Tools for Designing and Evaluating Hospital Inpatient Rooms
Authors: Quan Xiaobo , Joseph Anjali , Nanda Upali
Published: January 2017

A growing body of research shows that hospital inpatient room design greatly impacts healthcare outcomes, although research is often difficult for designers to understand and apply in decision making and postoccupancy evaluation (POE). The purpose of this study was to create evidence–based design checklists and POE tools for medical–surgical, intensive care, and maternity care patient rooms. Extensive literature reviews and focus groups with industry experts resulted in a set of design checklists and evaluation tools, including design considerations and features organized around 23 design goals. The tools were optimized after testing at multiple design firms and hospitals through questionnaire surveys and focus group discussions. The final product is an evidence–based toolkit with a series of features to increase usability. Testing results confirmed not only its validity and reliability, but also provided valuable lessons for further improvement. By facilitating the use of research evidence, the tools may contribute to improvements in the process of designing and evaluating healthcare facilities.
Examining Relationships between Physical Environments and Behaviors of Residents with Dementia in a Retrofit Special Care Unit
Authors: Mobley Christine , Leigh Katharine , Malinin Laura
Published: January 2017

Specialized Care Units (SCUs) in nursing home facilities offer care for individuals with late–stage dementia primarily when care in the home no longer supports physical and sociobehavioral needs. Prior research has primarily examined new facilities; however, due to market demand and financial constraints, many SCUs are retrofits of existing nursing homes. The purpose was to determine the capacity of the physical environment to enhance person–centered care (PCC) and identify potential design opportunities to help patients adapt to and cope with dementia progression to maintain quality of life (QoL). Grounded in empirical knowledge and best practices for SCU design, an instrumental case study of a retrofit SCU in the Rocky Mountain region of the United States examined relationships between the physical environment and the behavior of residents and staff. Qualitative and quantitative data were collected through a spatial inventory, staff e–survey, and behavioral observations in the unit's public spaces. Data indicate that even (less than ideal) retrofit SCU designs have the potential to support PCC goals significantly, and some physical conditions found to undermine PCC goals could be remedied by simple (low–cost) design interventions, suggesting staff may lack awareness of the capacity for the SCU physical environment to improve residents’ QoL. By linking design features from empirical studies and best practices with observed behaviors in a retrofit SCU, the primary contribution of our exploratory study is a framework of roles design features play in adaptation–coping and maladjustment–stress for people managing progressive dementia conditions. This framework suggests directions for future research and evolving methods to better understand the impacts of environmental designs on users’ QoL over the course of progressive illnesses, like dementia.
Perilesional Hyperintensity on T1‐Weighted Images in Intra‐Axial Brain Masses other than Cavernous Malformations
Authors: Nabavizadeh S. Ali , Pechersky Dasha , Schmitt J. Eric , Nasrallah MacLean , Wolf Ronald , Loevner Laurie , Mamourian Alexander C.
Published: January 2017

BACKGROUND AND PURPOSE

Hyperintensity on T1‐weighted imaging in perilesional vasogenic edema has been reported as a useful sign for differentiating cavernous malformation from other hemorrhagic intra‐axial masses. In this study, we investigated the frequency of perilesional hyperintensity on T1‐weighted imaging in patients with intra‐axial hemorrhagic and nonhemorrhagic brain masses.

METHODS

The study was performed with the approval of the institutional review board. Magnetic resonance images of 218 patients with 282 intra‐axial brain masses (129 metastases, 46 gliomas, 18 primary central nervous system lymphomas [PCNSLs], 25 intracerebral hemorrhages, 50 cavernous malformations, and 14 patients with brain abscesses) were evaluated. The signal intensity in perilesional area was qualitatively evaluated on T1‐weighted sequences. In addition, signal intensity in perilesional area was quantitatively measured on T1‐weighted sequences and normalized to the contralateral white matter.

RESULTS

Hyperintensity on T1‐weighted imaging in perilesional vasogenic edema was found in 12 (9%) of 129 metastases, 8 (16%) of 50 cavernous malformations, 1 (4%) in 25 nonneoplastic intracerebral hemorrhages, and none of the patients with high‐grade glioma, PCNSL, or abscess. All of the lesions with perilesional hyperintensity showed either acute or subacute hemorrhage. Pairwise comparison of qualitative hyperintensity on T1‐weighted imaging demonstrated no significant difference between the groups. Perilesional hyperintensity on T1‐weighted imaging showed high specificity in both metastasis and cavernous malformation groups (94%).

CONCLUSION

Perilesional hyperintensity on T1‐weighted imaging is not limited to cavernous malformations and frequently evident with melanoma and other hemorrhagic metastasis to the brain. In our experience, it was not seen in high‐grade glioma, PCNSL, and brain abscess.
Detection and pharmacokinetics of salmeterol in thoroughbred horses following inhaled administration
Authors: Fenwick S. J. , Hincks P. R. , Scarth J. P. , Wieder M. E. , Hillyer L. L. , Paine S. W.
Published: January 2017

Salmeterol is a man‐made beta‐2‐adrenergic receptor agonist used to relieve bronchospasm associated with inflammatory airway disease in horses. Whilst judicious use is appropriate in horses in training, they cannot race with clinically effective concentrations of medications under the British Horseracing Authority's Rules of Racing. Salmeterol must therefore be withdrawn prior to race day and pharmacokinetic (PK) studies used to establish formal detection time advice. Salmeterol xinafoate (Serevent Evohaler®) was administered (0.1 mg twice daily for 4.5 days) via inhalation to six horses. Urine and blood samples were taken up to 103 h postadministration. Hydrolysed samples were extracted using solid phase extraction. A sensitive Ultra high performance tandem mass spectrometry (UPLC‐MS/MS) method was developed, with a Lower limit of quantification (LLOQ) for salmeterol of 10 pg/mL in both matrices. The majority of salmeterol plasma concentrations, postlast administration, were below the method LLOQ and so unusable for PK analysis. Urine PK analysis suggested a half‐life consistent with duration of pharmacological effect. Average estimated urine concentration at steady‐state was obtained via PK modelling and used to estimate a urine concentration of 59 ± 34 pg/mL as a marker of effective lung concentration. From this, potential detection times were calculated using a range of safety factors.
Pharmacokinetics and selected pharmacodynamics of romifidine following low‐dose intravenous administration in combination with exercise to quarter horses
Authors: Knych H. K. , Stanley S. D. , McKemie D. S. , Steinmetz S. J.
Published: January 2017

Romifidine is an alpha‐2 adrenergic agonist used for sedation and analgesia in horses. As it is a prohibited substance, its purported use at low doses in performance horses necessitates further study. The primary goal of the study reported here was to describe the serum concentrations and pharmacokinetics of romifidine following low‐dose administration immediately prior to exercise, utilizing a highly sensitive liquid chromatography–tandem mass spectrometry assay that is currently employed in many drug testing laboratories. An additional objective was to describe changes in heart rate and rhythm following intravenous administration of romifidine followed by exercise. Eight adult Quarter Horses received a single intravenous dose of 5 mg (0.01 mg/kg) romifidine followed by 1 h of exercise. Blood samples were collected and drug concentrations measured at time 0 and at various times up to 72 h. Mean ± SD systemic clearance, steady‐state volume of distribution and terminal elimination half‐life were 34.1 ± 6.06 mL/min/kg and 4.89 ± 1.31 L/kg and 3.09 ± 1.18 h, respectively. Romifidine serum concentrations fell below the LOQ (0.01 ng/mL) and the LOD (0.005 ng/mL) by 24 h postadministration. Heart rate and rhythm appeared unaffected when a low dose of romifidine was administered immediately prior to exercise.
A national research and development blueprint for sustainable lake basin management in Malaysia
Authors: Sharip Zati , Suratman Saim , Shaaban Ahmad J.
Published: January 2017

The deterioration of water quality in lakes resulting from unsustainable catchment practices requires concerted efforts to address them, in the form of cooperation among government agencies and institutions, private bodies and the community‐at‐large. Research that provides an understanding of a lake's ecosystem is an important aspect of making informed decisions for sustainable management and governance of lakes. The present study describes the findings of literature reviews on Malaysian lakes, and the national efforts made to establish an agenda for lake research and development in Malaysia directed towards integrated lake basin management (ILBM). The main findings and outcomes of the National Lake Research Blueprint workshop in April 2014 on the issues facing lakes and reservoirs are highlighted. Seven research themes were identified, namely (i) ecosystem services and socio‐economic development, (ii) governance, (iii) water quality and pollution, (iv) eco‐hydrology and basin management, (v) biodiversity and natural products, (vi) physical limnology and hydrodynamics and (vii) technology. The goal is to enhance research and development on sustainable lake basin management directed to conservation and development targets. The findings of this study provide an integrated research framework that can support ILBM governance elements (pillars) elsewhere, and to call for researchers to participate in much‐needed research areas.
Impacts of dam construction on streamflows during drought periods in the Upper Colorado River Basin, Texas
Authors: Mix Ken , Groeger Alan W. , Lopes Vicente L.
Published: January 2017

The purpose of this study was to assess the impacts of dam construction on streamflow during a severe drought in the upper Colorado River basin (TX), upstream of Lake Buchanan reservoir. The region has experienced severe, prolonged droughts over the past century. To ameliorate the effects of drought, and increase water storage for use during dry periods, several dams were constructed on the mainstem and tributaries of the Colorado River upstream of Lake Buchanan since the late‐1940s. Analysis of flow at the gauge above Lake Buchanan indicated streamflow was significantly reduced during the recent drought (2009–2014), compared with streamflows during the ‘drought of record’ (1950–1957). The construction of these upstream dams reduced streamflow by intercepting and storing water. It is concluded that building reservoirs in the western portion of the basin, largely in response to past droughts, although increasing water supplies for local uses, exacerbated the downstream effects of the hydrological drought, essentially making it the worst in recorded history.
Natural history of nonimmune‐mediated thrombocytopenia and acute kidney injury in pediatric open‐heart surgery
Authors: Tew Shannon , Fontes Manuel L. , Greene Nathaniel H. , Kertai Miklos D. , Ofori‐Amanfo George , Jaquiss Robert D. B. , Lodge Andrew J. , Ames Warwick A. , Homi Hercilia Mayumi , Machovec Kelly A. , Jooste Edmund H.
Published: January 2017

Objective

Thrombocytopenia and acute kidney injury (AKI) are common following pediatric cardiac surgery with cardiopulmonary bypass (CPB). However, the relationship between postoperative nadir platelet counts and AKI has not been investigated in the pediatric population. Our objective was to investigate this relationship and examine independent predictors of AKI.

Design

After IRB approval, we performed a retrospective review of the institution's medical records and database. Setting: This study was performed at a single institution over a 5‐year period. Patients: We included patients <21 years of age undergoing cardiac surgery with CPB. Interventions: Demographics, laboratory, and surgical characteristics were captured, and clinical event rates were recorded. Measurements: Descriptive statistics were used to evaluate platelet and creatinine distributions. T‐tests and chi‐squared tests were used to compare characteristics among Acute Kidney Injury Network groups. Multivariable logistic and ordinal logistic regression models were used to determine the association of our predictor of interest, postoperative nadir platelet count and AKI.

Results

Eight hundred and fourteen patients (23% infants and 23% neonates) were included in the analysis. Postoperative platelet counts decreased 48% from baseline reaching a mean nadir value of 150 × 109·l−1 on postoperative day 3. AKI occurred in 37% of patients including 13%, 17%, and 6% with Acute Kidney Injury Network stages 1, 2, and 3, respectively. The magnitude of nadir platelet counts correlated with the severity of AKI. Independent predictors of severity of AKI include nadir platelet counts, CPB time, Aristotle score, patient weight, intra‐operative packed red blood cell transfusion, and having a heart transplant procedure.

Conclusions

In pediatric open‐heart surgery, thrombocytopenia and AKI occur commonly following CPB. Our findings show a strong association between nadir platelet counts and the severity of AKI.
Down‐regulation of BnDA1, whose gene locus is associated with the seeds weight, improves the seeds weight and organ size in Brassica napus
Authors: Wang Jie‐Li , Tang Min‐Qiang , Chen Sheng , Zheng Xiang‐Feng , Mo Hui‐Xian , Li Sheng‐Jun , Wang Zheng , Zhu Ke‐Ming , Ding Li‐Na , Liu Sheng‐Yi , Li Yun‐Hai , Tan Xiao‐Li
Published: January 2017

Brassica napus L. is an important oil crop worldwide and is the main raw material for biofuel. Seed weight and seed size are the main contributors to seed yield. DA1 (DA means big in Chinese) is an ubiquitin receptor and negatively regulates seed size. Down‐regulation of AtDA1 in Arabidopsis leads to larger seeds and organs by increasing cell proliferation in integuments. In this study, BnDA1 was down‐regulated in B. napus by over expressed of AtDA1R358K, which is a functional deficiency of DA1 with an arginine‐to‐lysine mutation at the 358th amino acid. The results showed that the biomass and size of the seeds, cotyledons, leaves, flowers and siliques of transgenic plants all increased significantly. In particular, the 1000 seed weight increased 21.23% and the seed yield per plant increased 13.22% in field condition. The transgenic plants had no negative traits related to yield. The candidate gene association analysis demonstrated that the BnDA1 locus was contributed to the seeds weight. Therefore, our study showed that regulation of DA1 in B. napus can increase the seed yield and biomass, and DA1 is a promising target for crop improvement.
Synthetic lethality: emerging targets and opportunities in melanoma
Authors: Thompson Nicola , Adams David J. , Ranzani Marco
Published: January 2017

Great progress has been made in the treatment of melanoma through use of targeted therapies and immunotherapy. One approach that has not been fully explored is synthetic lethality, which exploits somatically acquired changes, usually driver mutations, to specifically kill tumour cells. We outline the various approaches that may be applied to identify synthetic lethal interactions and define how these interactions may drive drug discovery efforts.
High neutrophil : lymphocyte ratio is associated with refractory Kawasaki disease
Authors: Cho Hong‐Je , Bak So Young , Kim Su Yeong , Yoo Rita , Baek Hae‐Sung , Yang Seung , Hwang Il‐Tae , Ban Ji‐Eun
Published: January 2017

Background

The clinical significance of the neutrophil : lymphocyte ratio (NLR) has not yet been fully elucidated in Kawasaki disease (KD). The purpose of this study was to investigate the relationship between NLR and response to i.v. immunoglobulin (IVIG), and its effect on coronary abnormalities in KD.

Methods

A total of 196 KD patients treated with IVIG were analyzed. Baseline NLR was evaluated immediately before IVIG therapy and the patients classified into two groups according to NLR. The clinical data, other inflammatory biomarkers, and coronary complications were also assessed.

Results

Kawasaki disease patients with NLR ≥ 5 had a greater incidence of IVIG refractoriness than the NLR < 5 group (31.7% vs 4.3%, P < 0.001), but this was not related to the development of coronary abnormalities. The change in NLR after IVIG (i.e. ΔNLR) was significantly decreased in the coronary abnormality group (2.65 ± 1.88 vs 3.81 ± 2.55, P = 0.042). On multivariate analysis, high NLR and CRP were independent predictors of IVIG refractoriness during the acute phase of KD (P = 0.032 in NLR; P = 0.029 in CRP, respectively).

Conclusions

High NLR was closely associated with resistance to IVIG, but it was not related to the occurrence of coronary abnormalities in KD. Low ΔNLR after IVIG, however, was significantly associated with coronary artery abnormalities.
Tidal marsh restoration stimulates the growth of winter shorebird populations in a temperate estuary
Authors: Kelly John P. , Condeso T. Emiko
Published: January 2017

The regional responses of winter shorebird populations in the nearly 3,000 ha estuary of Tomales Bay, California, to the restoration of 223 ha of historic tidal wetlands were evaluated for 27 years: 19 years prior to tidal reintroduction and 8 years after tidal reintroduction. We used interrupted time series analyses to measure the spatial extent of the restoration effect and to model the magnitude and length of time associated with the gradual, restoration‐induced growth of winter shorebird populations in the bay. Expanded, regional benefits of the restoration were revealed by consistent patterns of winter shorebird population growth. Eight years after tidal reintroduction, overall shorebird abundances in southern Tomales Bay nearly tripled in response to the restoration. Substantial winter population growth by most species in southern Tomales Bay was evident within 3 years after tidal reintroduction, and maximum responses to the restoration were estimated to be predominantly achieved within 8 years. In contrast to strong effects of tidal marsh restoration on winter shorebird populations in southern Tomales Bay, no significant overall responses were exhibited by shorebirds in the northern portion of the bay, although marginal evidence of expanded effects on a few species in northern Tomales Bay were suggested. The results illustrate the importance of accounting for restoration effects beyond the spatial and temporal boundaries of the restored habitat, to consider both the potentially expanded benefits and the spatial limits of those benefits to regional wildlife populations.
Revisiting the Narrative Approach of Estimating Tax Multipliers
Authors: Hebous Shafik , Zimmermann Tom
Published: January 2017

We analyze whether popular measures of narrative tax shocks can be treated as relevant instruments for observable endogenous tax series of interest. We find that narrative tax measures are only weakly correlated with cyclically adjusted tax revenues for the US and the UK. Using weak‐instrument robust inference, narrative tax measures often yield insignificant estimates of tax multipliers. We conclude that the literature currently understates the uncertainty associated with estimating the tax multiplier using the narrative approach.
Wealth, Wages, and Wedlock: Explaining the College Gender Gap Reversal
Authors: Reijnders Laurie S. M.
Published: January 2017

In this paper, I study the role of changes in the wage structure and expectations about marriage in explaining the college gender gap reversal. With strongly diminishing marginal utility of wealth and in the presence of a gender wage gap, single women have a greater incentive than single men to invest in education. Marriage‐market distortions tend to depress the overall benefit of education for women relative to men. I develop a tractable two‐period model and parameterize it using US census data for the cohort born in 1950. I then show that it can generate a reversal and that the most important driving force for this is the decline in marriage rates.
Competitive traits of the invasive grass Arundo donax are enhanced by carbon dioxide and nitrogen enrichment
Authors: Nackley L , Hough‐Snee N , Kim S‐H
Published: January 2017

Increased atmospheric carbon dioxide (CO2) and soil nitrogen (N) may confer competitive advantages to invasive species over native plant species. We conducted a two‐way factorial experiment, growing the model invasive plant Arundo donax in CO2 growth chambers to test how CO2 and N availability interact to affect plant growth and biomass allocation. CO2 was supplied at c. 400 mg L−1 and c. 750 mg L−1. N was supplied as ammonium nitrate at 640, 320 and 80 mg L−1. We hypothesised that the fertilisation effect of CO2 enrichment would offset limitations from N deficiency. The results indicated that A. donax plants grown with enriched CO2 and abundant N accumulated approximately 50–100% more biomass and allocated approximately 50% more biomass to rhizomes than plants grown under ambient CO2 conditions. Neither treatment affected the leaf area per unit mass (specific leaf area; SLA). Greater growth will likely increase A. donax's competitive potential, because increased rhizome biomass has been associated with increased stress tolerance and post‐disturbance resprouting capacity. The consistent SLA under all treatments suggests that A. donax has a morphological strategy that prioritises increasing leaf quantity over increasing individual leaves' photosynthetic potential. These results reveal the ecological strategies that contribute to the successful establishment, dominance and persistence of this invasive plant species.
Corrigendum: Connected components of affine Deligne–Lusztig varieties in mixed characteristic
Authors: Chen Miaofen , Kisin Mark , Viehmann Eva
Published: January 2017

We correct an error in our paper ‘Connected components of affine Deligne–Lusztig varieties in mixed characteristic’.
de Sitter symmetries and inflationary scalar-vector models
Authors: Valenzuela Toledo Cesar Alonso , Beltrán Almeida Juan , Motoa-Manzano Josue
Published: January 2017

In this paper, we study the correspondence between a field theory in de Sitter space in D-dimensions and a dual conformal feld theory in a euclidean space in (D - 1)-dimensions. In particular, we investigate the form in which this correspondence is established for a system of interacting scalar and a vector fields propagating in de Sitter space. We analyze some necessary (but not sucient) conditions for which conformal symmetry is preserved in the dual theory in (D - 1)-dimensions, making possible the establishment of the correspondence. The discussion that we address in this paper is framed on the context of inationary cosmology. Thusly, the results obtained here pose some relevant possibilities of application to the calculation of the fields’s correlation functions and of the primordial curvature perturbation \zeta, in inationary models including coupled scalar and vector fields.
Kepler and the origins of pre-Newtonian mass
Authors: Hecht Eugene
Published: January 2017

The technical concept of “mass” is traced from its medieval origins in theology up to, but not including, Newton's Principia. Building on the advances of the Middle Ages, Kepler conceived, albeit in rudimentary form, the fundamental physical ideas of mass, “inertia,” and gravitational “mutual attraction.” These splendid concepts were later developed and carried forward into Newton's era by several 17th-century natural philosophers. Unlike his three planetary laws, Kepler's physics has long gone unappreciated by the scientific community. Nonetheless, it formed the conceptual foundation for much of classical dynamics.
Interactions between uniformly magnetized spheres
Authors: Edwards Boyd F. , Riffe D. M. , Ji Jeong-Young , Booth William A.
Published: January 2017

We use simple symmetry arguments suitable for undergraduate students to demonstrate that the magnetic energy, forces, and torques between two uniformly magnetized spheres are identical to those between two point magnetic dipoles. These arguments exploit the equivalence of the field outside of a uniformly magnetized sphere with that of a point magnetic dipole, and pertain to spheres of arbitrary sizes, positions, and magnetizations. The point dipole/sphere equivalence for magnetic interactions may be useful in teaching and research, where dipolar approximations for uniformly magnetized spheres can now be considered to be exact. The work was originally motivated by interest in the interactions between collections of small neodymium magnetic spheres used as desk toys.
Uranium Glass: A Glowing Alternative to Conventional Sources of Radioactivity
Authors: Boot Roeland
Published: January 2017

There is a relatively simple way of using radioactive material in classroom experiments: uranium glass, which provides teachers with a suitable substance. By using the right computer software and a radiation sensor, it can be demonstrated that uranium glass emits radiation at a greater rate than the background radiation and with the aid of UV light a bright green luster appears. Therefore, with two pieces of uranium glass, students can learn about two different physical phenomena: fluorescence and radioactivity.
Using a Cell Phone to Investigate the Skin Depth Effect in Salt Water
Authors: Rayner John
Published: January 2017

This paper describes an experimental investigation of the skin depth effect for electromagnetic waves in salt water using a cell phone that is immersed to a critical depth where it no longer responds when called. We show that this critical depth is directly proportional to the theoretical skin depth for a range of salt concentrations.
A Physical Proof of the Pythagorean Theorem
Authors: Treeby David
Published: January 2017

What proof of the Pythagorean theorem might appeal to a physics teacher? A proof that involved the notion of mass would surely be of interest. While various proofs of the Pythagorean theorem employ the circumcenter and incenter of a right-angled triangle, we are not aware of any proof that uses the triangle’s center of mass. This note details one such proof. Though far from the most elegant approach, we believe it to be novel.
Manchester’s Magiscope: An Interesting Optics Puzzle
Authors: Lancor Rachael , Lancor Brian
Published: January 2017

The Magiscope was an attraction at Manchester’s department store in Madison, WI, in 1939 that allowed children to peek into Santa’s workshop (as shown in Fig. 1). The “magiscope” was a telescope-like device that gave children the illusion they were looking at a distant Santa, when in fact they were looking at a fabricated workshop on an upper level of the department store. In this article, we describe how we used the puzzle of the magiscope as a final assessment for our optics unit in an introductory physics course.
A Student Diffusion Activity
Authors: Kutzner Mickey , Pearson Bryan
Published: January 2017

Diffusion is a truly interdisciplinary topic bridging all areas of STEM education. When biomolecules are not being moved through the body by fluid flow through the circulatory system or by molecular motors, diffusion is the primary mode of transport over short distances. The direction of the diffusive flow of particles is from high concentration toward low concentration.
How Magnus Bends the Flying Ball – Experimenting and Modeling
Authors: Timková V. , Ješková Z.
Published: January 2017

Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways, resulting in a so-called banana kick that can confuse the goalkeeper. These surprising effects attract students’ attention such that the motion of sports balls can be used to capture the interest of students towards the physics behind it. However, to study and analyze the motion of a real ball kicked in a playfield is not an easy task. Instead of the large-scale full-size sports ball motion, there can be designed and studied simpler experiments that can be carried out in the classroom. Moreover, digital technologies that are available at schools enable students to collect data from the experiment easily in a reasonable time. The mathematical model based on the analysis of forces acting on the ball flying in the air can be used to simulate the motion in order to understand the basic physical principles of the motion so that the best correspondence may be found.
A smartphone-based introductory astronomy experiment: Seasons investigation
Authors: Durelle Jeremy , Jones Jennifer , Merriman Steven , Balan Aurelian
Published: January 2017

Light sensor probes are useful in experiments that investigate seasonal variations and the nature of light. However, having a dedicated light probe is not always possible or even convenient for many instructors. Modern smartphone technology gives instructors the ability to use built-in light sensors as an inexpensive alternative. This introductory experiment will have students use a smartphone loaded with a light detection app to quantitatively determine how changing latitude on Earth changes flux received. The purpose is to have students discover how the different seasons arise from the Earth-Sun system. While performing the experiment and analyzing the data, students will also discover the following important and relevant physical relationships: distance from light source and light brightness (flux), latitude and flux, and Earth’s orientation and location (latitude) of maximum flux. By piecing all of these relationships together, students are able to explain the origins of the different seasons based on the data they collected.
I love my baffling, backward, counterintuitive, overly complicated magnitudes
Authors: Sirola Christopher
Published: January 2017

All professions have their jargon. But astronomy goes the extra parsec. Here’s an example. Vega, one of the brighter stars in the night sky, has an apparent magnitude (i.e., an apparent brightness) of approximately zero. Polaris, the North Star, has an apparent magnitude of about +2. Despite this, Vega appears brighter than Polaris, and not by two, but by a factor of about six times.
Two-dimensional model of the interaction of a plane acoustic wave with nozzle edge and wing trailing edge
Authors: Faranosov Georgy A. , Bychkov Oleg P.
Published: January 2017

The interaction of a plane acoustic wave with two-dimensional model of nozzle edge and trailing edge is investigated theoretically by means of the Wiener-Hopf technique. The nozzle edge and the trailing edge are simulated by two half-planes with offset edges. Shear layer behind the nozzle edge is represented by a vortex sheet supporting Kelvin-Helmholtz instability waves. The considered configuration combines two well-known models (nozzle edge and trailing edge), and reveals additional interesting physical aspects. To obtain the solution, the matrix Wiener-Hopf equation is solved in conjunction with a requirement that the full Kutta condition is imposed at the edges. Factorization of the kernel matrix is performed by the combination of Padé approximation and the pole removal technique. This procedure is used to obtain numerical results. The results indicate that the diffracted acoustic field may be significantly intensified due to scattering of hydrodynamic instability waves into sound waves provided that the trailing edge is close enough to the vortex sheet. Similar mechanism may be responsible for the intensification of jet noise near a wing.
Interior sound field control using generalized singular value decomposition in the frequency domain
Authors: Pasco Yann , Gauthier Philippe-Aubert , Berry Alain , Moreau Stéphane
Published: January 2017

The problem of controlling a sound field inside a region surrounded by acoustic control sources is considered. Inspired by the Kirchhoff-Helmholtz integral, the use of double-layer source arrays allows such a control and avoids the modification of the external sound field by the control sources by the approximation of the sources as monopole and radial dipole transducers. However, the practical implementation of the Kirchhoff-Helmholtz integral in physical space leads to large numbers of control sources and error sensors along with excessive controller complexity in three dimensions. The present study investigates the potential of the Generalized Singular Value Decomposition (GSVD) to reduce the controller complexity and separate the effect of control sources on the interior and exterior sound fields, respectively. A proper truncation of the singular basis provided by the GSVD factorization is shown to lead to effective cancellation of the interior sound field at frequencies below the spatial Nyquist frequency of the control sources array while leaving the exterior sound field almost unchanged. Proofs of concept are provided through simulations achieved for interior problems by simulations in a free field scenario with circular arrays and in a reflective environment with square arrays.
Precursor wave in a layered waveguide
Authors: Shanin A. V.
Published: January 2017

The precursor wave (often called the first arriving signal) in a layered waveguide is investigated. It is known that the velocity of such a signal is close to the velocity of the fastest medium in the waveguide, and it may be bigger than the fastest group velocity given by the dispersion diagram of the waveguide. Usually the precursor pulse decays with the propagation distance. A model layered waveguide is studied in the paper. It is shown that the precursor is associated with the pseudo-branch structure of the dispersion diagram. The velocity of the precursor is determined by the slope of the pseudo-branch. The decay is exponential and it depends on the structure of the pseudo-branch. Three approaches to precursors are described in the paper: the Miklowitz–Randles approach based on analytical continuation of the dispersion diagram, the leaky wave approach, and the approximate technique based on the properties of the real dispersion diagram.
A sterile animal model for neuroinflammation?
Authors: Fung Lawrence K.
Published: January 2017

MRI-guided pulsed focused ultrasound combined with systemic infusion of contrast agent microbubbles induces local neuroinflammation in the rat.
CAR T cells engage in anticancer martial arts
Authors: Gill Saar
Published: January 2017

A clever redesign of the chimeric antigen receptor T cell concept turns a cancer-mediated immunosuppressive cytokine into a growth signal.
Influence of
rhlR
and
lasR
on Polymyxin Pharmacodynamics in Pseudomonas aeruginosa and Implications for Quorum Sensing Inhibition with Azithromycin
Authors: Bulman Zackery P. , Ly Neang S. , Lenhard Justin R. , Holden Patricia N. , Bulitta Jürgen B. , Tsuji Brian T.
Published: January 2017

The impact of quorum sensing on polymyxin and azithromycin pharmacodynamics was assessed in
Pseudomonas aeruginosa
PAO1 and an isogenic
rhlR
/
lasR
double knockout. For polymyxin B, greater killing against the
rhlR
/
lasR
knockout than against PAO1 was observed at 10
8
CFU/ml (polymyxin B half-maximal effective concentration [EC
50
], 5.61 versus 12.5 mg/liter, respectively;
P
< 0.005). Polymyxin B combined with azithromycin (256 mg/liter) was synergistic against each strain, significantly reducing the respective polymyxin B EC
50
compared to those with monotherapy (
P
< 0.005), and is a promising strategy by which to combat
P. aeruginosa
.
Impact of Extended Duration of Artesunate Treatment on Parasitological Outcome in a Cytocidal Murine Malaria Model
Authors: Walker Leah A. , Sullivan David J.
Published: January 2017

Artemisinin-based combination therapies are a key pillar in global malaria control and are recommended as a first-line
Plasmodium falciparum
treatment. They rely upon a rapid 4-log-unit reduction in parasitemia by artemisinin compounds with a short half-life and the killing of remaining parasites by a partner compound with a longer half-life. Current treatment guidelines stipulate giving three 24-h-interval doses or six 12-h-interval doses over a 3-day period. Due to the short half-life of artesunate and artemether, almost all of the resulting cytocidal activity is confined within a single 48-h asexual
P. falciparum
cycle. Here, we utilized a luciferase reporter,
Plasmodium berghei
ANKA, in a cytocidal model in which treatment was initiated at high parasitemia, allowing us to monitor a greater than 3-log-unit reduction in parasite density, as well as 30-day survival. In this study, we demonstrated that increasing the artesunate duration from spanning one asexual cycle to spanning three asexual cycles while keeping the total dose constant results in enhanced cytocidal activity. Single daily artesunate doses at 50 mg/kg of body weight over 7 days were the minimum necessary for curative monotherapy. In combination with a single sub-human-equivalent dose of the partner drug amodiaquine or piperaquine, the three-asexual-cycle artesunate duration was able to cure 75% and 100% of mice, respectively, whereas 0% and 33% cures were achieved with the single-asexual-cycle artesunate duration. In summary, cytocidal activity of the artemisinin compounds, such as artesunate, can be improved solely by altering the dosing duration.
In Vitro
Activity of Ceftolozane-Tazobactam against Multidrug-Resistant Nonfermenting Gram-Negative Bacilli Isolated from Patients with Cystic Fibrosis
Authors: Grohs Patrick , Taieb Gary , Morand Philippe , Kaibi Iheb , Podglajen Isabelle , Lavollay Marie , Mainardi Jean-Luc , Compain Fabrice
Published: January 2017

Ceftolozane-tazobactam was tested against 58 multidrug-resistant nonfermenting Gram-negative bacilli (35
Pseudomonas aeruginosa
, 11
Achromobacter xylosoxydans
, and 12
Stenotrophomonas maltophilia
isolates) isolated from cystic fibrosis patients and was compared to ceftolozane alone, ceftazidime, meropenem, and piperacillin-tazobactam. Ceftolozane-tazobactam was the most active agent against
P. aeruginosa
but was inactive against
A. xylosoxydans
and
S. maltophilia
. In time-kill experiments, ceftolozane-tazobactam had complete bactericidal activity against 2/6 clinical isolates (33%).