bluuebunny/crossref_metadata_2025 huggingface dataset:
Elucidation of the Pathway to Astaxanthin in the Flowers of Adonis aestivalis
Authors: Cunningham Francis X. , Gantt Elisabeth
Published: August 2011

A few species in the genus Adonis are the only land plants known to produce the valuable red ketocarotenoid astaxanthin in abundance. Here, we ascertain the pathway that leads from the β-rings of β-carotene, a carotenoid ubiquitous in plants, to the 3-hydroxy-4-keto-β-rings of astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4’-dione) in the blood-red flowers of Adonis aestivalis, an ornamental and medicinal plant commonly known as summer pheasant's eye. Two gene products were found to catalyze three distinct reactions, with the first and third reactions of the pathway catalyzed by the same enzyme. The pathway commences with the activation of the number 4 carbon of a β-ring in a reaction catalyzed by a carotenoid β-ring 4-dehydrogenase (CBFD), continues with the further dehydrogenation of this carbon to yield a carbonyl in a reaction catalyzed by a carotenoid 4-hydroxy-β-ring 4-dehydrogenase, and concludes with the addition of an hydroxyl group at the number 3 carbon in a reaction catalyzed by the erstwhile CBFD enzyme. The A. aestivalis pathway is both portable and robust, functioning efficiently in a simple bacterial host. Our elucidation of the pathway to astaxanthin in A. aestivalis provides enabling technology for development of a biological production process and reveals the evolutionary origin of this unusual plant pathway, one unrelated to and distinctly different from those used by bacteria, green algae, and fungi to synthesize astaxanthin.
PhyscomitrellaCyclin-Dependent Kinase A Links Cell Cycle Reactivation to Other Cellular Changes during Reprogramming of Leaf Cells
Authors: Ishikawa Masaki , Murata Takashi , Sato Yoshikatsu , Nishiyama Tomoaki , Hiwatashi Yuji , Imai Akihiro , Kimura Mina , Sugimoto Nagisa , Akita Asaka , Oguri Yasuko , Friedman William E. , Hasebe Mitsuyasu , Kubo Minoru
Published: August 2011

During regeneration, differentiated plant cells can be reprogrammed to produce stem cells, a process that requires coordination of cell cycle reactivation with acquisition of other cellular characteristics. However, the factors that coordinate the two functions during reprogramming have not been determined. Here, we report a link between cell cycle reactivation and the acquisition of new cell-type characteristics through the activity of cyclin-dependent kinase A (CDKA) during reprogramming in the moss Physcomitrella patens. Excised gametophore leaf cells of P. patens are readily reprogrammed, initiate tip growth, and form chloronema apical cells with stem cell characteristics at their first cell division. We found that leaf cells facing the cut undergo CDK activation along with induction of a D-type cyclin, tip growth, and transcriptional activation of protonema-specific genes. A DNA synthesis inhibitor, aphidicolin, inhibited cell cycle progression but prevented neither tip growth nor protonemal gene expression, indicating that cell cycle progression is not required for acquisition of protonema cell-type characteristics. By contrast, treatment with a CDK inhibitor or induction of dominant-negative CDKA;1 protein inhibited not only cell cycle progression but also tip growth and protonemal gene expression. These findings indicate that cell cycle progression is coordinated with other cellular changes by the concomitant regulation through CDKA;1.
Prospects for biological control of Ambrosia artemisiifolia in Europe: learning from the past
Authors: GERBER E , SCHAFFNER U , GASSMANN A , HINZ H L , SEIER M , MÜLLER‐SCHÄRER H
Published: August 2011

Gerber E, Schaffner U, Gassmann A, Hinz HL, Seier M & Müller‐Schärer H (2011). Prospects for biological control of Ambrosia artemisiifolia in Europe: learning from the past. Weed Research51, 559–573.

The recent invasion by Ambrosia artemisiifolia (common ragweed) has, like no other plant, raised the awareness of invasive plants in Europe. The main concerns regarding this plant are that it produces a large amount of highly allergenic pollen that causes high rates of sensitisation among humans, but also A. artemisiifolia is increasingly becoming a major weed in agriculture. Recently, chemical and mechanical control methods have been developed and partially implemented in Europe, but sustainable control strategies to mitigate its spread into areas not yet invaded and to reduce its abundance in badly infested areas are lacking. One management tool, not yet implemented in Europe but successfully applied in Australia, is biological control. Almost all natural enemies that have colonised A. artemisiifolia in Europe are polyphagous and cause little damage, rendering them unsuitable for a system management approach. Two fungal pathogens have been reported to adversely impact A. artemisiifolia in the introduced range, but their biology makes them unsuitable for mass production and application as a mycoherbicide. In the native range of A. artemisiifolia, on the other hand, a number of herbivores and pathogens associated with this plant have a very narrow host range and reduce pollen and seed production, the stage most sensitive for long‐term population management of this winter annual. We discuss and propose a prioritisation of these biological control candidates for a classical or inundative biological control approach against A. artemisiifolia in Europe, capitalising on past experiences from North America, Asia and Australia.
Distribution and Diversity of Phytophthora species in Nursery Irrigation Reservoir Adopting Water Recycling System During Winter Months
Authors: Ghimire Sita R. , Richardson Patricia A. , Kong Ping , Hu Jiahuai , Lea‐Cox John D. , Ross David S. , Moorman Gary W. , Hong Chuanxue
Published: August 2011

Irrigation water recycling is an increasingly important practice in agriculture in the context of diminishing water supply and the regulatory requirements in some parts of the world. This practice potentially accumulates and disseminates plant pathogens including Phytophthora species that pose a great threat to agriculture and forest ecosystems. Despite a high economic importance of Phytophthora species, the current understanding of their aquatic ecology is very limited. Therefore, a study was conducted to investigate the distribution and diversity of Phytophthora species in an irrigation reservoir of a commercial nursery in eastern Virginia over two consecutive winters. Multiple baits were deployed in surface water at a run‐off entrance, 20, 40, 60 and 80 m from the entrance and near the pump inlet and at various depths at the 20‐m station. Ten different Phytophthora species were detected in this study that included P. citrophthora, P. gonapodyides, P. hydropathica, P. inundata, P. irrigata, P. megasperma, P. pini, P. polonica, P. syringae and P. tropicalis. Phytophthora recovery declined through the winters from November to March. It also declined with distance from the run‐off entrance. These results suggest that water decontamination during winter irrigation events is required at this nursery and possibly in the nurseries from the southern part of the United States. The placement of the pump inlet away from run‐off entrance may be a viable strategy to reduce the crop health risk.
Perinatal morbidity associated with late preterm deliveries compared with deliveries between 37 and 40 weeks of gestation
Authors: Cheng YW , Kaimal AJ , Bruckner TA , Hallaron DR , Caughey AB
Published: August 2011

Please cite this paper as: Cheng Y, Kaimal A, Bruckner T, Hallaron D, Caughey A. Perinatal morbidity associated with late preterm deliveries compared with deliveries between 37 and 40 weeks of gestation. BJOG 2011;118:1446–1454.

Objective  To estimate the risk of short‐term complications in neonates born between 34 and 36 weeks of gestation.

Design  This is a retrospective cohort study.

Setting  Deliveries in 2005 in the USA.

Population  Singleton live births between 34 and 40 weeks of gestation.

Methods  Gestational age was subgrouped into 34, 35, 36 and 37–40 completed weeks of gestation. Statistical comparisons were performed using chi‐square test and multivariable logistic regression models, with 37–40 weeks of gestation designated as referent.

Main outcome measures  Perinatal morbidities, including 5‐minute Apgar scores, hyaline membrane disease, neonatal sepsis/antibiotics use, and admission to the intensive care unit.

Results  In all, 175 112 neonates were born between 34 and 36 weeks in 2005. Compared with neonates born between 37 and 40 weeks, neonates born at 34 weeks had higher odds of 5‐minute Apgar <7 (adjusted odds ratio [aOR] 5.51, 95% CI 5.16–5.88), hyaline membrane disease (aOR 10.2, 95% CI 9.44–10.9), mechanical ventilation use >6 hours (aOR 9.78, 95% CI 8.99–10.6) and antibiotic use (aOR 9.00, 95% CI 8.43–9.60). Neonates born at 35 weeks were similarly at risk of morbidity, with higher odds of 5‐minute Apgar <7 (aOR 3.42, 95% CI 3.23–3.63), surfactant use (aOR 3.74, 95% CI 3.21–4.22), ventilation use >6 hours (aOR 5.53, 95% CI 5.11–5.99) and neonatal intensive‐care unit admission (aOR 11.3, 95% CI 11.0–11.7). Neonates born at 36 weeks remain at higher risk of morbidity compared with deliveries at 37–40 weeks of gestation.

Conclusions  Although the risk of undesirable neonatal outcomes decreases with increasing gestational age, the risk of neonatal complications in late preterm births remains higher compared with infants delivered at 37–40 weeks of gestation.
A long‐term prospective study to compare the effects of vaginal and abdominal hysterectomy on micturition and defecation
Authors: Lakeman MME , van der Vaart CH , Roovers JPWR
Published: August 2011

Please cite this paper as: Lakeman M, van der Vaart C, Roovers J. A long‐term prospective study to compare the effects of vaginal and abdominal hysterectomy on micturition and defecation. BJOG 2011;118:1511–1517.

Objective  We compared micturition and defecation symptoms with the route of hysterectomy over a period of 10 years.

Design  Prospective multicentre observational study.

Setting  Thirteen teaching hospitals in the Netherlands.

Population  A total of 430 women who underwent vaginal or abdominal hysterectomy for benign conditions (pelvic organ prolapse excluded).

Methods  The presence and discomfort experienced as a result of micturition and defecation symptoms were assessed using validated questionnaires before surgery, and at 6 weeks, 6 months, 1 year, 3 years and 10 years after surgery. Statistically significant differences in symptoms between vaginal and abdominal hysterectomy were adjusted for pre‐operative differences in uterine descent, uterine size, parity and indication for hysterectomy.

Main outcome measure  Presence of bothersome micturition and defecation symptoms, as assessed by the Urogenital Distress Inventory (UDI) and Defecation Distress Inventory (DDI).

Results  Ten years after hysterectomy the response rate was 73%. Preoperatively, no differences were observed in the prevalence of micturition symptoms between patients who underwent vaginal and abdominal hysterectomy. However, 10 years after vaginal hysterectomy, significantly more women had been treated for micturition symptoms (18 versus 8%; P = 0.02; adjusted OR 3.8, 95% CI 1.2–11.6). Defecation symptoms also seemed more common after vaginal hysterectomy (58 versus 46%; P = 0.08). After adjustment, no statistically significant differences in defecation symptoms were found.

Conclusions  Despite the same incidence of micturition symptoms before surgery, patients undergoing vaginal hysterectomy are more likely to seek medical help for micturition symptoms. Defecation symptoms were also more common after vaginal hysterectomy; however, this difference was not statistically significant.
Missed opportunities for type 2 diabetes testing following gestational diabetes: a population‐based cohort study
Authors: Shah BR , Lipscombe LL , Feig DS , Lowe JM
Published: August 2011

Please cite this paper as: Shah B, Lipscombe L, Feig D, Lowe J. Missed opportunities for type 2 diabetes testing following gestational diabetes: a population‐based cohort study. BJOG 2011;118:1484–1490.

Objectives  Few women with gestational diabetes (GDM) are tested for type 2 diabetes in the postpartum period. Whether women are having physician visits that could be an opportunity to improve testing rates is unknown. This study sought to evaluate population‐level trends in postpartum diabetes testing after GDM, and to evaluate postpartum physician care for these women.

Design  Population‐based cohort study.

Setting  Ontario, Canada.

Population  Women who delivered between 1994 and 2008.

Methods  Using population‐level healthcare databases, we identified 47 691 women with GDM. They were matched to women without GDM.

Main outcome measures  An oral glucose tolerance test (OGTT) within 6 months postpartum, the specialty of the physician ordering the test, and ambulatory care visits with physicians from various specialties within 6 months postpartum were recorded.

Results  Most women with GDM did not receive an OGTT, although testing rates increased slowly over the 14 years of the study, compared with no change in testing for women who had not had GDM. Virtually all women with GDM had postpartum visits with a family physician or obstetrician, but few OGTTs were ordered by physicians from these specialties.

Conclusions  Despite a slow increase in testing over time and high rates of postpartum visits to family physicians and obstetricians, few women with GDM received the recommended diabetes test. This represents a missed opportunity in a high‐risk population. Interventions to change test ordering that target family physicians and obstetricians are most likely to increase the proportion of women with GDM who receive postpartum diabetes testing.
Breaking a paradigm: cosmopolitan and abundant freshwater actinobacteria are low GC
Authors: Ghai Rohit , McMahon Katherine D. , Rodriguez‐Valera Francisco
Published: August 2011

Free‐living Actinobacteria are universally recognized as high‐GC organisms. Freshwater Actinobacteria have been identified as abundant and prevalent members of freshwater microbial communities, but the two most common lineages (acI and acIV) have remained impossible to culture to date. We have analysed metagenomic data from lakes and estuaries, and show that members of acI and acIV are indeed abundant. We then show that the majority of actinobacterial reads from metagenomic datasets (both lakes and estuaries) are consistently low GC. Analysis of assembled scaffolds from these datasets also confirms that actinobacterial scaffolds are primarily low GC, although high‐GC scaffolds were also observed, indicating both types of Actinobacteria coinhabit. Phylogenetic analysis of 16S rRNA gene sequences, both from PCR‐based clone libraries and metagenomic reads, and the discovery of a low‐GC scaffold containing a partial 16S rRNA gene, points to the abundance of the well‐known acI and acIV lineages of freshwater in these habitats, both of which appear to be low GC.
Correlative microscopy for phylogenetic and ultrastructural characterization of microbial communities
Authors: Knierim Bernhard , Luef Birgit , Wilmes Paul , Webb Richard I. , Auer Manfred , Comolli Luis R. , Banfield Jillian F.
Published: August 2011

Transmission electron microscopy (TEM) can provide ultrastructural information for cells in microbial community samples and phylogenetic information can be recovered via molecular surveys. Here we report an approach to link these data sets by coupling fluorescence in situ hybridization (FISH) with either conventional biological or cryogenic TEM. The method could fundamentally improve our understanding of the organization and functioning of microbial communities in natural systems.
Surgical management of recurrent laryngeal neuropathy
Authors: Cramp P. , Barakzai S. Z.
Published: August 2011

Recurrent laryngeal neuropathy (RLN, laryngeal hemiplegia, laryngeal paralysis, ‘roaring’) is common in the equine industry with a prevalence ranging from 2.6–11% in light breeds (Raphel 1982;Lane 1987;Morris and Seeherman 1990) up to 38% in draught breeds (Brakenhoffet al. 2006;Perkinset al. 2009). There are a number of different surgical treatments currently available and more being developed. This article aims to discuss factors affecting choice of treatment and then provide an evidence‐based approach to describe surgical approaches, success rates and morbidity. Specific details of surgical methods are not given as they are readily available in surgical textbooks (Stick 2006;McGorumet al. 2007).
Poincaré inequalities, embeddings, and wild groups
Authors: Naor Assaf , Silberman Lior
Published: August 2011

We present geometric conditions on a metric space (Y,dY) ensuring that, almost surely, any isometric action onYby Gromov’s expander-based random group has a common fixed point. These geometric conditions involve uniform convexity and the validity of nonlinear Poincaré inequalities, and they are stable under natural operations such as scaling, Gromov–Hausdorff limits, and Cartesian products. We use methods from metric embedding theory to establish the validity of these conditions for a variety of classes of metric spaces, thus establishing new fixed point results for actions of Gromov’s ‘wild groups’.
Effect of Semi-Geodesic Winding on the Vibration Characteristics of Filament Wound Shells of Revolution
Authors: Kayran Altan , İbrahimoğlu Can Serkan
Published: August 2011

The effect of semigeodesic winding on the free vibration characteristics of filament wound shells of revolution is studied. For this purpose multisegment numerical integration technique is extended to the solution of the free vibration problem of composite shells of revolution which are wound along the semigeodesic fiber paths counting on the preset friction used during the winding process. Sample results are obtained for truncated conical and spherical shells of revolution and the effect of preset friction on the vibration characteristics of filament wound shells of revolution is particularly analyzed. Results show that when the preset friction is increased natural frequencies of higher circumferential vibration modes also increase irrespective of the initial winding angle, and the circumferential bending stiffness stands out as the dominant parameter governing the natural frequencies of higher circumferential vibration modes.
Modeling of Systems With Position-Dependent Mass Revisited: A Port-Hamiltonian Approach
Authors: Jeltsema Dimitri , Dòria-Cerezo Arnau
Published: August 2011

It is known that straightforward application of the classical Lagrangian and Hamiltonian formalism to systems with mass varying explicitly with position may lead to discrepancies in the formulation of the equations of motion. Systems with mass varying explicitly with position often arise from situations where the partitioning of a closed system of constant mass leads to open subsystems that exchange mass among themselves. One possible solution is to introduce additional nonconservative generalized forces that account for these effects. However, it remains unclear how to systematically interconnect the Lagrangian or Hamiltonian subsystems. In this note, systems with mass varying explicitly with position and their properties are studied in the port-Hamiltonian modeling framework. The port-Hamiltonian formalism combines the classical Lagrangian and Hamiltonian approach with network modeling and is applicable to various engineering domains. One of the strong aspects of the port-Hamiltonian formalism is that power-preserving interconnections between port-Hamiltonian subsystems results in another port-Hamiltonian system with composite energy and interconnection structure. The motion of a heavy cable being deployed from a reel by the action of gravity is used as an example.
Fault, State, and Unknown Input Reconstruction in Nonlinear Systems Using Sliding Mode Observers
Authors: R Sharma , M Aldeen
Published: August 2011

In this paper, a new approach to estimation of unknown inputs and faults in a class of nonlinear systems is presented. The approach is based on the design of a cascade connection of two sliding mode observers. The first observer is used for the estimation of state and unknown inputs and the second is used for the fault detection and isolation. An important feature of the proposed approach is that the state trajectories do not leave the sliding manifold even in the presence of unknown inputs and faults. This allows for faults and unknown inputs to be completely reconstructed based on the information retrieved from the equivalent output injection signals. The proposed approach is tested on a nonlinear model of single link flexible joint robot system.
Dosimetric intercomparison for multicenter clinical trials using a patient‐based anatomic pelvic phantom
Authors: Ebert M. A. , Harrison K. M. , Howlett S. J. , Cornes D. , Bulsara M. , Hamilton C. S. , Kron T. , Joseph D. J. , Denham J. W.
Published: August 2011

Purpose:

To assess dose delivery accuracy to clinically significant points in a realistic patient geometry for two separate pelvic radiotherapy scenarios.

Methods:

An inhomogeneous pelvic phantom was transported to 36 radiotherapy centers in Australia and New Zealand. The phantom was treated according to Phase III rectal and prostate trial protocols. Point dose measurements were made with thermoluminescent dosimeters (TLDs) and an ionisation chamber. Comprehensive site‐demographic, treatment planning, and physical data were collected for correlation with measurement outcomes.

Results:

Dose delivery to the prescription point for the rectal treatment was consistent with planned dose (mean difference between planned and measured dose − 0.1 ± 0.3% std err). Dose delivery in the region of the sacral hollow was consistently higher than planned (+1.2 ± 0.2%). For the prostate treatment, dose delivery to the prostate volume was consistent with planned doses (−0.49 ± 0.2%) and planned dose uniformity, though with a tendency to underdose the PTV at the prostate‐rectal border. Measured out‐of‐field doses were significantly higher than planned.

Conclusions:

A phantom based on realistic anatomy and heterogeneity can be used to comprehensively assess the influence of multiple aspects of the radiotherapy treatment process on dose delivery. The ability to verify dose delivery for two trials with a single phantom was advantageous.
Investigating the limit of detectability of a positron emission mammography device: A phantom study
Authors: Shkumat Nicholas A. , Springer Adam , Walker Christopher M. , Rohren Eric M. , Yang Wei T. , Adrada Beatriz E. , Arribas Elsa , Carkaci Selin , Chuang Hubert H. , Santiago Lumarie , Mawlawi Osama R.
Published: August 2011

Purpose:

A new positron emission mammography (PEM) device (PEM Flex Solo II, Naviscan Inc., San Diego, CA) has recently been introduced and its performance characteristics have been documented. However, no systematic assessment of its limit of detectability has been evaluated. The aim of this work is to investigate the limit of detectability of this new PEM system using a novel, customized breast phantom.

Methods:

Two sets of F‐18 infused gelatin breast phantoms of varying thicknesses (2, 4, 6, and 8 cm) were constructed with and without (blank) small, shell‐less contrast objects (2 mm thick disks) of varying diameters (3–14.5 mm) [volumes: 0.15–3.3 cc] and activity concentration to background ratio (ACR) (2.7–58). For the phantom set with contrast objects, the disks were placed centrally inside the phantoms and both phantom sets were imaged for a period of 10 min on the PEM device. In addition, scans for the 2 and 6 cm phantoms were repeated at different times (0, 90, and 150 min) post phantom construction to evaluate the impact of total activity concentration (count density) on lesion detectability. Each object from each phantom scan was then segmented and placed randomly in a corresponding blank phantom image. The resulting individual images were presented blindly to seven physician observers (two nuclear medicine and five breast imaging radiologists) and scored in a binary fashion (1—correctly identified object, 0—incorrect). The sensitivity, specificity, and accuracy of lesion detectability were calculated and plots of sensitivity versus ACR and lesion diameters for different phantom thicknesses and count density were generated.

Results:

The overall (mean) detection sensitivity across all variables was 0.68 (95% CI: [0.64, 0.72]) with a corresponding specificity of 0.93 [0.87, 0.98], and diagnostic accuracy of 0.72 [0.70, 0.75]. The smallest detectable object varied strongly as a function of ACR, as sensitivity ranged from 0.36 [0.29, 0.44] for the smallest lesion size (3 mm) to 0.80 [0.75, 0.84] for the largest (14.5 mm).

Conclusions:

The detectability performance of this PEM system demonstrated its ability to resolve small objects with low activity concentration ratios which may assist in the identification of early stage breast cancer. The results of this investigation can be used to correlate lesion detectability with tumor size, ACR, count rate, and breast thickness.
High-Speed Video Analysis in a Conceptual Physics Class
Authors: Desbien Dwain M.
Published: August 2011

The use of probe ware and computers has become quite common in introductory physics classrooms.1 Video analysis is also becoming more popular and is available to a wide range of students through commercially available and/or free software.2,3 Video analysis allows for the study of motions that cannot be easily measured in the traditional lab setting and also allows real-world situations to be analyzed. Many motions are too fast to easily be captured at the standard video frame rate of 30 frames per second (fps) employed by most video cameras. This paper will discuss using a consumer camera that can record high-frame-rate video in a college-level conceptual physics class. In particular this will involve the use of model rockets to determine the acceleration during the boost period right at launch and compare it to a simple model of the expected acceleration.
Pepper's Ghost
Authors: Greenslade Thomas B.
Published: August 2011

Without applications of physics such as counter-weighted sets and backdrops, inclined planes, stage lighting instruments, and other mechanisms for deus ex machina, dramatic productions would revert to the words only—fine for Shakespeare and Becket, but not good for audiences who are accustomed to experiencing plays with the eye as well as the ear. Pepper's Ghost is a 19th-century stage illusion, based on basic optical principles, that can find its way into your introductory classroom.
Reanalyzing the Ampère-Maxwell Law
Authors: Hill S. Eric
Published: August 2011

In a recent TPT article,1 I addressed a common miscommunication about Faraday's law, namely, that introductory texts often say the law expresses a causal relationship between the magnetic fields time variation and the electric fields circulation. In that article, I demonstrated that these field behaviors share a common cause in a time-varying current density. From that, many readers may have rightly guessed at a symmetric conclusion: while the Ampère-Maxwell law is commonly said to express a causal relation between the electric fields time variation and the magnetic fields circulation, these field behaviors share a distinct, common cause. Together, Faraday's law and the Ampère-Maxwell law constitute half of Maxwell's laws that form a foundation for almost all of electricity and magnetism. By misrepresenting these two laws, introductory texts not only present students with unnecessary conceptual hurdles early in their physics educations but also leave them with enduring misunderstandings about the very foundation of electricity and magnetism. Fortunately, compared to what is commonly taught, the actual cause of these field variations is conceptually simpler and more consistent with what the students will have already learned in the introductory texts' own earlier chapters.
The Rolling Release Rulapult
Authors: West Joseph , Ross Seth , Flesher James
Published: August 2011

The “rulapult” is a low-cost, easy-to-construct, ruler-based catapult for use in the classroom. It is made from durable, inexpensive items that are easy to store. Most of the components can be found with a visit to one or two local stores. A set of 12 complete rulapults can be constructed for less than $150, including the one-time cost of the only tool needed for construction, a single handheld one-hole paper punch. The unit price per rulapult approaches $10.25 as the number of rulapults constructed becomes “large.” A rulapult can be constructed by a single middle school student in less than five minutes. Ping-Pong® balls or marshmallows are suggested for use as projectiles as they pose a minimal safety hazard. The range of a typical rulapult when firing a Ping-Pong ball is approximately 4.0 m, just right for classroom or hallway testing. The smaller (1-cm size) marshmallows have a range of about 5.0 m, but due to their “squishy” nature, the range is less consistent from shot to shot. For the rest of the discussion, it is presumed that the projectile is a Ping-Pong ball (the ball). The ball can easily knock over a large Styrofoam™ cup, but despite its impressive range and “knock-down power,” the rulers used are “limp” enough that a direct hit to your hand by the ruler will not cause noticeable pain or injury.
Optics Demonstration with Student Eyeglasses Using the Inquiry Method
Authors: James Mark C.
Published: August 2011

A favorite qualitative optics demonstration I perform in introductory physics classes makes use of students' eyeglasses to introduce converging and diverging lenses.1 Taking on the persona of a magician, I walk to the back of the classroom and approach a student wearing glasses. The top part of Fig. 1 shows a glasses-wearing student who is farsighted in her left eye and has a slight astigmatism in her right eye.
Experiments Using Cell Phones in Physics Classroom Education: The Computer-Aided g Determination
Authors: Vogt Patrik , Kuhn Jochen , Müller Sebastian
Published: August 2011

This paper continues the collection of experiments that describe the use of cell phones as experimental tools in physics classroom education.1–4 We describe a computer-aided determination of the free-fall acceleration g using the acoustical Doppler effect. The Doppler shift is a function of the speed of the source. Since a free-falling objects speed is changing linearly with time, the Doppler shift is also changing with time. It is possible to measure this shift using software that is both easy to use and readily available. Students will use the time-dependency of the Doppler shift to experimentally determine the acceleration due to gravity by using a cell phone as a freely falling object emitting a sound with constant frequency.
A Tale of Two SCIDs
Authors: Shaw Kit L. , Kohn Donald B.
Published: August 2011

Gene therapy for severe combined immunodeficiency: Do the benefits outweigh the risks?
Herding CATS
Authors: Petsko Gregory A.
Published: August 2011

The National Center for Advancing Translational Sciences seems primed to polarize scientists while possibly failing to drive biomedical research and development forward.
PTPN22: A Risky Business
Authors: Cheng Mickie H.
Published: August 2011

Healthy carriers of the major risk variant of
PTPN22
show early signs of autoimmunity.
Brings Back Memories
Authors: Wang Wei
Published: August 2011

A neurophysiology study of prefrontal cortical neurons may advance medications that alleviate age-related decline in memory.
Dot/Icm Type IVB Secretion System Requirements for Coxiella burnetii Growth in Human Macrophages
Authors: Beare Paul A. , Gilk Stacey D. , Larson Charles L. , Hill Joshua , Stead Christopher M. , Omsland Anders , Cockrell Diane C. , Howe Dale , Voth Daniel E. , Heinzen Robert A.
Published: August 2011

Central to Q fever pathogenesis is replication of the causative agent,
Coxiella burnetii
, within a phagolysosome-like parasitophorous vacuole (PV) in mononuclear phagocytes.
C. burnetii
modulates PV biogenesis and other host cell functions, such as apoptotic signaling, presumably via the activity of proteins delivered to the host cytosol by a Dot/Icm type IVB secretion system (T4BSS). In this study, we utilized a
C. burnetii
strain carrying IcmD inactivated by the
Himar1
transposon to investigate the requirements for Dot/Icm function in
C. burnetii
parasitism of human THP-1 macrophage-like cells. The
icmD
::Tn mutant failed to secrete characterized T4BSS substrates, a defect that correlated with deficient replication, PV development, and apoptosis protection. Restoration of type IVB secretion and intracellular growth of the
icmD
::Tn mutant required complementation with
icmD
,
-J
, and
-B
, indicating a polar effect of the transposon insertion on downstream
dot
/
icm
genes. Induction of
icmDJB
expression at 1 day postinfection resulted in
C. burnetii
replication and PV generation. Collectively, these data prove that T4BSS function is required for productive infection of human macrophages by
C. burnetii
. However, illustrating the metabolic flexibility of
C
.
burnetti
, the
icmD
::Tn mutant could replicate intracellularly when sequestered in a PV generated by wild-type bacteria, where Dot/Icm function is provided in
trans
, and within a phenotypically similar PV generated by the protozoan parasite
Leishmania amazonensis
, where host cells are devoid of Dot/Icm T4BSS effector proteins.

IMPORTANCE
Coxiella burnetii
, the cause of human Q fever, is the only bacterial pathogen known to replicate in a vacuole resembling a phagolysosome. The organism manipulates host macrophages to promote the biogenesis of a vacuolar compartment permissive for growth. By analogy to the well-established cellular microbiology of
Legionella pneumophila
, the Dot/Icm type IVB secretion system of
C. burnetii
is implicated as a critical virulence factor in host cell modification that delivers proteins with effector functions directly into the host cell cytosol. Using new genetic tools, we verify that Dot/Icm function is essential for productive infection of human macrophages by
C. burnetii
. Interestingly, despite the production of homologous secretion systems,
L. pneumophila
and
C. burnetii
have strikingly different temporal requirements for Dot/Icm function during their respective infectious cycles.
Effects of exercise and human contact on animal welfare in a dog shelter
Authors: Menor‐Campos D. J. , Molleda‐Carbonell J. M. , López‐Rodríguez R.
Published: August 2011

The aim of the study is to investigate the reduction of stress in dogs in municipal shelters through easy‐to‐implement activities, ie, 25‐minute sessions of exercise and human contact, that do not require a significant investment in terms of funding, staff or time. The results demonstrate that the dogs taking part in these sessions have lower salivary cortisol levels (F=121.42; P<0.05) and achieve better scores on a behaviour test (t17 =4.27; P=0.001). It can therefore be affirmed that the exercise and human contact protocol proposed in the present study diminishes stress and improves the welfare of dogs housed in shelters.
TWISTED ALEXANDER POLYNOMIALS AND CHARACTER VARIETIES OF 2-BRIDGE KNOT GROUPS
Authors: KIM TAEHEE , MORIFUJI TAKAYUKI
Published: August 2011

We study the twisted Alexander polynomial from the viewpoint of the SL (2, ℂ)-character variety of nonabelian representations of a knot group. It is known that if a knot is fibered, then the twisted Alexander polynomials associated with nonabelian SL (2, ℂ)-representations are all monic. In this paper, we show that for a 2-bridge knot there exists a curve component in the SL (2, ℂ)-character variety such that if the knot is not fibered then there are only finitely many characters in the component for which the associated twisted Alexander polynomials are monic. We also show that for a 2-bridge knot of genus g, in the above curve component for all but finitely many characters the associated twisted Alexander polynomials have degree 4g - 2.
SURFACES IN 𝔼3MAKING CONSTANT ANGLE WITH KILLING VECTOR FIELDS
Authors: MUNTEANU MARIAN IOAN , NISTOR ANA IRINA
Published: August 2011

In the present paper we classify curves and surfaces in Euclidean 3-space which make constant angle with a certain Killing vector field. Moreover, we characterize the catenoid and Dini's surface in terms of constant angle surfaces.
A STUDY OF THE INTERACTION BETWEEN A FIVE-LEVEL ATOM AND A SINGLE-MODE CAVITY FIELD: FAN-TYPE
Authors: ABDEL-WAHAB N. H.
Published: August 2011

In this paper, a model describing the interaction of a five-level (85 Rb ) atom with one-mode cavity field including Kerr nonlinearity is discussed. Analytical solution for this model is presented when the atom is initially prepared in its upper state. The obtained results are then employed to examine the dynamical behavior of atomic inversion, field statistics and field squeezing when the input field is initially considered in a coherent state. It is found that the atom-field properties are influenced by the changing of the coupling constants, the detuning parameters and the Kerr medium.
β-Tetrabromo-meso-tetrakis(4′-substituted phenyl)porphyrins: synthesis and electrochemical redox properties
Authors: Bhyrappa P. , Velkannan V.
Published: August 2011

A series of 2,3,12,13-tetrabromo-5,10,15,20-tetrakis(4′-substituted phenyl)porphyrins, H2 T(4′-R Ph) PBr4 ( R = OCH3 , t-butyl, H and CO2CH3 ) and their metal ( Co(II) , Cu(II) , and Zn(II) ) complexes were synthesized and their electrochemical redox properties were explored. The plot of E1/2vs. the Hammett parameter (σp) of the substituents (R) follow a fairly linear relationship for the ring centered redox potentials.
Farnesol, an isoprenoid, improves metabolic abnormalities in mice via both PPARα-dependent and -independent pathways
Authors: Goto Tsuyoshi , Kim Young-Il , Funakoshi Kozue , Teraminami Aki , Uemura Taku , Hirai Shizuka , Lee Joo-Young , Makishima Makoto , Nakata Rieko , Inoue Hiroyasu , Senju Hiroyuki , Matsunaga Masayoshi , Horio Fumihiko , Takahashi Nobuyuki , Kawada Teruo
Published: August 2011

Peroxisome proliferator-activated receptors (PPARs) control energy homeostasis. In this study, we showed that farnesol, a naturally occurring ligand of PPARs, could ameliorate metabolic diseases. Obese KK-Ay mice fed a high-fat diet (HFD) containing 0.5% farnesol showed significantly decreased serum glucose level, glucosuria incidence, and hepatic triglyceride contents. Farnesol-containing HFD upregulated the mRNA expressions of PPARα target genes involved in fatty acid oxidation in the liver. On the other hand, farnesol was not effective in upregulating the mRNA expressions of PPARγ target genes in white adipose tissues. Experiments using PPARα-deficient [(−/−)] mice revealed that the upregulation of fatty acid oxidation-related genes required PPARα function, but the suppression of hepatic triglyceride accumulation was partially PPARα-dependent. In hepatocytes isolated from the wild-type and PPARα (−/−) mice, farnesol suppressed triglyceride synthesis. In luciferase assay, farnesol activated both PPARα and the farnesoid X receptor (FXR) at similar concentrations. Moreover, farnesol increased the mRNA expression level of a small heterodimer partner known as one of the FXR target genes and decreased those of sterol regulatory element-binding protein-1c and fatty acid synthase in both the wild-type and PPARα (−/−) hepatocytes. These findings suggest that farnesol could improve metabolic abnormalities in mice via both PPARα-dependent and -independent pathways and that the activation of FXR by farnesol might contribute partially to the PPARα-independent hepatic triglyceride content-lowering effect. To our knowledge, this is the first study on the effect of the dual activators of PPARα and FXR on obesity-induced metabolic disorders.
Alternative splice variant PGC-1α-b is strongly induced by exercise in human skeletal muscle
Authors: Norrbom J. , Sällstedt E. K. , Fischer H. , Sundberg C. J. , Rundqvist H. , Gustafsson T.
Published: August 2011

The present study investigated whether exercise induces the expression of PGC-1α splice variants in human skeletal muscle and the possible influence of metabolic perturbation on this response. The subjects exercised one leg for 45 min with restricted blood flow (R-leg), followed by 45 min of exercise using the other leg at the same absolute workload but with normal blood flow (NR-leg). This ischemic model (R-leg) has been shown previously to induce a greater metabolic perturbation and enhance the expression of PGC-1α beyond that observed in the NR-leg. Cultured human myotubes were used to test suggested exercise-induced regulatory stimuli of PGC-1α. We showed, for the first time, that transcripts from both the canonical promoter (PGC-1α-a) and the proposed upstream-located promoter (PGC-1α-b) are present in human skeletal muscle. Both transcripts were upregulated after exercise in the R-leg, but the fold change increase of PGC-1α-b was much greater than that of PGC-1α-a. No differences were observed between the two conditions regarding the marker for calcineurin activation, MCIP1, or p38 phosphorylation. AMPK phosphorylation increased to a greater extent in the R-leg, and AICAR stimulation of cultured human myotubes induced the expression of PGC-1α-a and PGC-1α-b. AICAR combined with norepinephrine yielded an additive effect on the PGC-1α-b expression only. Our results indicate clearly that exercise can activate an upstream promoter in humans and support AMPK as a major regulator of transcripts from the canonical PGC-1α promoter and the involvement of β-adrenergic stimulation in combination with AMPK in the regulation of PGC-1α-b.
Urinary C-type natriuretic peptide excretion: a potential novel biomarker for renal fibrosis during aging
Authors: Jeson Sangaralingham S. , Heublein Denise M. , Grande Joseph P. , Cataliotti Alessandro , Rule Andrew D. , McKie Paul M. , Martin Fernando L. , Burnett John C.
Published: August 2011

Renal aging is characterized by structural changes in the kidney including fibrosis, which contributes to the increased risk of kidney and cardiac failure in the elderly. Studies involving healthy kidney donors demonstrated subclinical age-related nephropathy on renal biopsy that was not detected by standard diagnostic tests. Thus there is a high-priority need for novel noninvasive biomarkers to detect the presence of preclinical age-associated renal structural and functional changes. C-type natriuretic peptide (CNP) possesses renoprotective properties and is present in the kidney; however, its modulation during aging remains undefined. We assessed circulating and urinary CNP in a Fischer rat model of experimental aging and also determined renal structural and functional adaptations to the aging process. Histological and electron microscopic analysis demonstrated significant renal fibrosis, glomerular basement membrane thickening, and mesangial matrix expansion with aging. While plasma CNP levels progressively declined with aging, urinary CNP excretion increased, along with the ratio of urinary to plasma CNP, which preceded significant elevations in proteinuria and blood pressure. Also, CNP immunoreactivity was increased in the distal and proximal tubules in both the aging rat and aging human kidneys. Our findings provide evidence that urinary CNP and its ratio to plasma CNP may represent a novel biomarker for early age-mediated renal structural alterations, particularly fibrosis. Thus urinary CNP could potentially aid in identifying subjects with preclinical structural changes before the onset of symptoms and disease, allowing for the initiation of strategies designed to prevent the progression of chronic kidney disease particularly in the aging population.
Primary Maxillofacial Large B-Cell Lymphoma in Immunocompetent Patients: Report of 5 Cases
Authors: Velez Ines , Hogge Maritzabel
Published: August 2011

Lymphomas of the oral cavity represent 5% of all lymphomas. They usually occur in immunocompromised patients. Lymphoma arising within a single bone, without visceral or lymph node involvement, is known as primary intraosseous lymphoma. It is a rare condition and constitutes 3.1% of malignant bone tumors and 5% of extranodal lymphomas. Primary lymphoma of the jaw is seldom seen and it is often misdiagnosed. Clinically, the manifestations are usually similar to an odontogenic tumor, cyst, or infection. Radiographically it appears as a radiolucent area that may mimic endodontic lesion, periodontal pathology, or odontogenic cyst or tumor. The initial presentation is commonly followed by multiple unnecessary extractions and/or root canal treatments. We present five cases of rare primary lymphoma of the maxillofacial complex, four of them intraosseous.
Phosphodiesterase Type 4D Gene Polymorphism: Association with the Response to Short-Acting Bronchodilators in Paediatric Asthma Patients
Authors: Labuda Malgorzata , Laberge Sophie , Brière Julie , Bérubé Denis , Beaulieu Patrick , Pastinen Tomi , Krajinovic Maja
Published: August 2011

Short-acting b2-adrenergic receptor agonists are commonly used bronchodilators for symptom relief in asthmatics. The aim of this study was to test whether genetic variants inPDE4Dgene, a key regulator of b2-adrenoceptor-induced cAMP turnover in airway smooth muscle cells, affect the response to short-acting b2-agonists. Bronchodilator responsiveness was assessed in 133 asthmatic children by % change in baseline forced expiratory volume in one second (FEV1) after administration of albuterol. The analyses were performed in patients with airway obstruction (FEV1/FVC ratio below 90%,n=93). FEV1  % change adjusted for baseline FEV1values was significantly different between genotypes of rs1544791 G/A polymorphism (P=0.006) and −1345 C/T (rs1504982) promoter variation (P=0.03). The association remained significant with inclusion of age, sex, atopy, and controller medication into multivariate model (P=0.004andP=0.02, resp.). Our work identifies new genetic variants implicated in modulation of asthma treatment, one of them (rs1544791) previously associated with asthma phenotype.
Severe Hemoperitoneum after Patient Self-Induced Fecal Evacuation
Authors: Gianesini S. , Lanzara S. , Stano R. , Santini S. , De Troia A. , Gennari S. , Vasquez G.
Published: August 2011

An increasing incidence of rectal injuries following patient self-induced harmful acts, aimed to sexual or laxatives porpouses, is a fact reported in literature (El-Ashaal et al., 2008). We herein report a case of severe hemoperitoneum related to a middle and upper rectal third seromuscolar tear caused by a self-induced fecal evacuation by means of an arrow with a covered cork tip. An urgent intestinal diversion by means of a Hartmann's operation was performed. The clinical case is presented in relation to the literature debate, regarding the issue of primary repair or resection and anastomosis versus fecal diversion for penetrating rectal injuries (Fabian, 2002; Cleary et al., 2006; Office of the Surgeon General, 1943; Busic et al., 2002). In conclusion, the importance of avoiding an anastomotic breakdown in a patient undergoing a hemorrhagic shock is highlighted.
Severe Tracheobronchomalacia after Prolonged Intubation of Multitrauma Patient
Authors: Sams V. G. , Lawson C. M. , Shibli A. B. , Taylor D. A. , Branca P. R.
Published: August 2011

Tracheobronchomalacia is a condition with significant morbidity with many etiologies including iatrogenic ones and should be considered in critically ill ventilated trauma patients. We present a case of a multitrauma patient who had difficulty weaning from the ventilator after prolonged intubation followed by tracheostomy tube placement. We describe her presentation, diagnosis, and management provide and as well a discussion of the condition.