bluuebunny/crossref_metadata_2025 huggingface dataset:
Antifibrotic peptide N‐acetyl‐Ser‐Asp‐Lys‐Pro (Ac‐SDKP): Opportunities for angiotensin‐converting enzyme inhibitor design
Authors: Douglas Ross G , Ehlers Mario R , Sturrock Edward D
Published: January 2013

The renin–angiotensin system (RAS) is central to regulation of blood pressure and electrolyte homeostasis.

 Angiotensin‐converting enzyme (ACE), a key protease in the RAS, has a range of substrates, including N‐acetyl‐Ser‐Asp‐Lys‐Pro (Ac‐SDKP). The peptide Ac‐SDKP is cleared almost exclusively by ACE, and specifically by the N‐domain active site of this enzyme.

 N‐Acetyl‐Ser‐Asp‐Lys‐Pro is a negative regulator of haematopoietic stem cell differentiation and is a potent antifibrotic agent. In this review, the physiological actions of Ac‐SDKP are presented, together with the potential clinical usefulness of raising Ac‐SDKP levels. This emphasizes the possible opportunity of N‐domain‐selective ACE inhibitors or ACE‐resistant Ac‐SDKP analogues for the treatment of fibrosis.
An Examination of Pay‐for‐Performance in General Practice in Australia
Authors: Greene Jessica
Published: January 2013

Objective

This study examines the impact of Australia's pay‐for‐performance (P4P) program for general practitioners (GPs). The voluntary program pays GPs A$40 and A$100 in addition to fee‐for‐service payment for providing patients recommended diabetes and asthma treatment over a year, and A$35 for screening women for cervical cancer who have not been screened in 4 years.

Design

Three approaches were used to triangulate the program's impact: (1) analysis of trends in national claims for incentivized services pre‐ and postprogram implementation; (2) fixed effects panel regression models examining the impact of GPs' P4P program participation on provision of incentivized services; and (3) in‐depth interviews to explore GPs' perceptions of their own response to the program.

Results

There was a short‐term increase in diabetes testing and cervical cancer screens after program implementation. The increase, however, was for all GPs. Neither signing onto the program nor claiming incentive payments was associated with increased diabetes testing or cervical cancer screening. GPs reported that the incentive did not influence their behavior, largely due to the modest payment and the complexity of tracking patients and claiming payment.

Implications

Monitoring and evaluating P4P programs is essential, as programs may not spark the envisioned impact on quality improvement.
A novel approach for the detection of early gastric cancer: Fluorescence spectroscopy of gastric juice
Authors: Deng Kai , Zhou Li Ya , Lin San Ren , Li Yuan , Chen Mo , Geng Qiu Ming , Li Yu Wen
Published: January 2013

Objective

This study aimed to investigate the efficacy of fluorescence spectroscopy of gastric juice for early gastric cancer (EGC) screening.

Methods

Gastric juice was collected from 101 participants who underwent endoscopy in the Outpatient Endoscopy Center of Peking University Third Hospital. The participants were divided into three groups: the normal mucosa or chronic non‐atrophic gastritis (NM‐CNAG) group (n = 35), advanced gastric cancer (AGC) group (n = 33) and EGC group (n = 33). Fluorescence spectroscopic analysis was performed in all the gastric juice samples and the maximum fluorescence intensity of the first peak (P1FI) was measured.

Results

The mean fluorescence intensity of P1FI of gastric juice in AGC (92.1 ± 10.7) and EGC (90.8 ± 12.0) groups was significantly higher than that in the NM‐CNAG group (55.7 ± 7.5) (AGC vs NM‐CNAG, P = 0.006 and EGC vs NM‐CNAG, P = 0.015, respectively). The areas under the receiver operating characteristic curves for the detection of AGC and EGC were 0.681 (95% confidence interval [CI] 0.553–0.810, P = 0.010) and 0.655 (95% CI 0.522–0.787, P = 0.028). With the P1FI of ≥47.7, the sensitivity, specificity and accuracy for detecting EGC were 69.7%, 57.1% and 63.2%, respectively.

Conclusions

The enhancement of P1FI of gastric juice occurs at the early stage of gastric cancer. Fluorescence spectroscopy of gastric juice may be used as a novel screening tool for the early detection of gastric cancer.
Seasonal patterns of habitat use by insectivorous bats in a subtropical African agro‐ecosystem dominated by macadamia orchards
Authors: Taylor Peter John , Monadjem Ara , Nicolaas Steyn Jacobus
Published: January 2013

We report on acoustic surveys of insectivorous bats conducted during seven months of the year using ANABAT recordings in two habitats (macadamia orchards and adjacent riparian bush) in a subtropical agro‐ecosystem in northern South Africa. We defined two functional foraging groups of bats based on their echolocation calls: (i) open‐air foragers (family Molossidae) having narrow‐band, low‐frequency, low duty cycle calls; and (ii) clutter‐edge foragers (families Miniopteridae and Vespertilionidae), having broad‐band, higher frequency, low duty cycle calls. Bat activity (number of bat passes) was not significantly influenced by habitat. Total bat activity and activity of both functional groups varied significantly between seasons, being highest in summer and autumn (coinciding with annual peaks in numbers of Twin spotted (Bathycoelia natalicola) and Green (Nezara spp) Stinkbugs, order Heteroptera, family Pentatomidae, and Macadamia Nut Borer moths, Cryptophlebia ombrodelta) and lower in winter and spring. No significant effect of moon phase was detected, either on total activity or activity of the two functional groups. We postulate that the significant pattern of seasonality of commuting and/or foraging activity of bats in macadamia orchards (which is more marked in open‐air foragers) may be driven by the seasonal abundance of pest insects such as stinkbugs and Macadamia Nut Borer moths.
Inflammation in the setting of chronic allograft dysfunction post‐kidney transplant: phenotype and genotype
Authors: Israni Ajay K. , Leduc Robert , Jacobson Pamala A. , Wildebush Winston , Guan Weihua , Schladt David , Matas Arthur J. , Oetting William S. ,   The DeKAF Genomics Investigators
Published: January 2013

Background

Chronic allograft dysfunction (CGD) is a common outcome in kidney transplants, but its pathogenesis is unclear. We investigated theCGDphenotype and single‐nucleotide polymorphisms (SNPs) associated withCGD.

Method

This prospective study enrolled 2336 transplants from seven transplant centers in North America.CGDwas defined as a >25% rise in serum creatinine relative to a three‐month post‐transplant baseline, requiring a kidney biopsy. We genotyped 2724SNPs in the initial 979 transplants, which form the test cohort.

Results

CGDoccurred 11.2 times per 100 person‐years at a median of 509 ± 387 days from the three‐month baseline.CGDwas independently associated with death‐censored, allograft failure, in an adjusted analysis [HR=20.6 (11.8–35.8, p < 0.001)]. Among 366 transplant recipients withCGD, 91% had inflammation on biopsy scores. 94 (26%) had inflammatory changes consistent with a diagnosis of concomitant acute rejection.SNPs inFM06andFM03,potential drug metabolism genes, were associated withCGD, after accounting for multiple testing.

Conclusion

CGDphenotype with concomitant inflammation is associated with increased risk of allograft failure.SNPs associated withCGDin novel drug metabolism and transport genes, will be validated in subsequent transplants.
Intra‐specific and inter‐specific variation in specific leaf area reveal the importance of abiotic and biotic drivers of species diversity across elevation and latitude
Authors: Hulshof Catherine M. , Violle Cyrille , Spasojevic Marko J. , McGill Brian , Damschen Ellen , Harrison Susan , Enquist Brian J.
Published: January 2013

Questions

Are patterns of intra‐ and inter‐specific functional trait variation consistent with greater abiotic filtering on community assembly at high latitudes and elevations, and greater biotic filtering at low latitudes and elevations?

Locations

Area de Conservación Guanacaste, Costa Rica; Santa Catalina Mountains, Arizona; Siskiyou Mountains, Oregon.

Methods

We measured woody plant species abundance and a key functional trait associated with competition for resources and environmental tolerance (specific leaf area, SLA) along elevational gradients in low‐latitude tropical (Costa Rica), mid‐latitude desert (Arizona) and high latitude mediterranean (southern Oregon) biomes. We explored patterns of abiotic and biotic filtering by comparing observed patterns of community‐weighted means and variances along elevational and latitudinal gradients to those expected under random assembly. In addition, we related trait variability to niches and explored how total trait space and breadth vary across broad spatial gradients by quantifying the ratio of intra‐ to inter‐specific variation.

Results

Both the community‐wide mean and variance of SLA decreased with increasing latitude, consistent with greater abiotic filtering at higher latitudes. Further, low‐elevation communities had higher trait variation than expected by chance, consistent with greater biotic filtering at low elevations. Finally, in the tropics and across latitude the ratio of intra‐ to inter‐specific variation was negatively correlated to species richness, which further suggests that biotic interactions influence plant assembly at low latitudes.

Conclusions

Intra‐ and inter‐specific patterns of SLA variation appeared broadly consistent with the idea that the relative strength of biotic and abiotic drivers on community assembly changes along elevational and latitudinal gradients; evidence for biotic drivers appeared more prominent at low latitudes and elevations and evidence for abiotic drivers appeared more prominent at high latitudes and elevations.
Adolescent predictors and associates of psychosocial functioning in young men and women: 11 year follow‐up findings from the Nord‐Trøndelag Health Study
Authors: Derdikman‐Eiron Ruth , Hjemdal Odin , Lydersen Stian , Bratberg Grete H. , Indredavik Marit S.
Published: January 2013

The aim of this paper was to investigate whether psychosocial functioning in adulthood (e.g., friends support, cohabitation, community connectedness and work satisfaction) could be predicted by mental health, subjective well‐being, social relations and behavior problems in adolescence, and whether gender was a moderator in these associations. Data were obtained from a major population‐based Norwegian study, the Nord‐Trøndelag Health Study (HUNT), in which 517 men and 819 women completed an extensive self‐report questionnaires at baseline (mean age 14.4 years) and at follow‐up (mean age 26.9 years). Community connectedness as well as work satisfaction were predicted by subjective well‐being. Cohabitation was predicted by male gender and frequency of meeting friends in adolescence, and friends support was predicted by frequency of meeting friends. Gender had a minor effect as a moderator. Frequency of meeting friends and subjective well‐being seemed to be the strongest adolescent predictors of psychosocial functioning in young adulthood. These findings may have implications both for prevention and intervention in adolescence, as well as for future research.
Distributed Generation, Using Battery/Photovoltaic System: Modeling and Simulation With Relative Controller Design
Authors: Naderi Peyman
Published: January 2013

Distributed generation (DG) using a parallel battery pack with photovoltaic (PV) system has been presented in this brief. Considering a two level inverter and a three phase transformer, a local load will be supplied by the DG and connected to a power grid. The DG has been connected to the high voltage network via a filter and a distribution power station. A nero-fuzzy network has been designed for the estimation of maximum power ability of PV and the connected dc/dc converter has been controlled relatively. So, the power management between the PV system and the battery pack can be confirmed. On the other hand, another controller has been designed for control of transferred power between the power network and the DG system that can control the battery pack power indirectly. Finally, a series of simulation results show the effectiveness of proposed method for some various conditions.
SENSING AND ACTUATING BIO-MATERIALS ON STANDARD CMOS SUBSTRATES
Authors: ABU-NIMEH FAISAL T. , SALEM FATHI M.
Published: January 2013

We present a low-cost, low-power, high efficiency, and portable integrated implementations of a lab-on-chip for magnetic molecular level sensing manipulation, and diagnosis. The design features an all-integrated programmable magnetic coil array for sensing and actuating small magnetic bead objects. The coil array is selectively and dynamically controlled using the smallest permissible vertical coil inductors in this technology. Each cell, composed of the coil and its logical control circuitry, can detect small objects in the order of 1 μm diameter as well as emit eight programmable magnetic field levels for manipulation. All array sensing and driving components are shared to reduce the overall imprint. They are tuned towards the 900 s MHz ISM band and incorporating high-speed serial row/column switching up to 40 MHz for seamless pseudo-parallel operation.
Price Discrimination and Bargaining: Empirical Evidence from Medical Devices
Authors: Grennan Matthew
Published: January 2013

Many important issues in business-to-business markets involve price discrimination and negotiated prices, situations where theoretical predictions are ambiguous. This paper uses new panel data on buyer-supplier transfers and a structural model to empirically analyze bargaining and price discrimination in a medical device market. While many phenomena that restrict different prices to different buyers are suggested as ways to decrease hospital costs (e.g., mergers, group purchasing organizations, and transparency), I find that: (i) more uniform pricing works against hospitals by softening competition; and (ii) results depend ultimately on a previously unexplored bargaining effect. (JEL C78, L13, L14, L64)
Selection on Moral Hazard in Health Insurance
Authors: Einav Liran , Finkelstein Amy , Ryan Stephen P , Schrimpf Paul , Cullen Mark R
Published: January 2013

We use employee-level panel data from a single firm to explore the possibility that individuals may select insurance coverage in part based on their anticipated behavioral (“moral hazard”) response to insurance, a phenomenon we label “selection on moral hazard.” Using a model of plan choice and medical utilization, we present evidence of heterogenous moral hazard as well as selection on it, and explore some of its implications. For example, we show that, at least in our context, abstracting from selection on moral hazard could lead to overestimates of the spending reduction associated with introducing a high-deductible health insurance option. (JEL D82, G22, I13, J32)
Tight Gas Reservoir Appraisal and Development Challenges for New LNG Supply from Australia
Authors: Al Kindi Azhar , Soh Martin T
Published: January 2013

The contemporary challenges operators face in appraising the next tranche of Australian gas reservoirs for liquefied natural gas supply is presented. These reservoirs are typically characterised as ‘tight’, with encountered permeability < 1 mD, and were considered ‘stranded’ resources under legacy gas pricing arrangements. Case study data will be presented to demonstrate the inadequacies of traditional reservoir appraisal approaches. Instead, creative and innovative methods are required to understand the degree of intra and inter reservoir connectivity and structural/stratigraphic compartmentalisation. Operators must now accept increased development cost and risk, in order for these projects to be sanctioned for development. It is clear that the era of easy gas supply from Australian giant gas fields is over.
North Oman Tight Gas Development
Authors: Lamers Edwin , Al Siyabi Hisham , Briner Andreas , Elliott David , Weissenbäck Markus , Al-Kindy Fahad
Published: January 2013

Production from conventional non-associated gas fields operated by PDO in North Oman has largely met demand from Oman’s domestic and LNG export requirements to-date. However, with domestic demand growing at around 5% per year and with continuing significant LNG sales contracts to be met, exploration has been stepped up in recent years to meet this demand, especially as new opportunities from conventional gas accumulations become rarer. Exploration successes over the last five years are increasingly restricted to deep, tight Amin sandstone reservoirs with porosities ranging from 2 to 10% and (ambient) permeabilities from 0.001 to 1 mD.

Following an extensive exploration campaign including a hunt for Basin Centre Gas during 2009-2011 focus has now shifted to the appraisal and early development of the Khulud cluster of fields, located in the Yibal-Fahud area.

Significant challenges exist over and above the tightness of the rock: target reservoirs are deep (4700-5200 m below Ground Level) and have high reservoir temperatures (160 to 190°C). Rock geomechanics are a critical issue: high fracture gradients mean that not all hydraulic fracturing jobs are successful. On top of all this, longer term well production will be impacted by relatively high Condensate Gas Ratios and associated water production.

With significant Gas-In-Place, the presence of infrastructure, notably the nearby Yibal gas processing plant, and the proven presence of sweet spots make the Khulud Cluster a prime candidate to provide the 2nd wave of production following conventional reservoirs and a possible working model for future tight and unconventional gas developments.

A 1 mln m3/d capacity Early Production System (EPS) is currently being constructed to de-risk and ‘right-size’ a cluster development by assessing Expected UltimateRecovery (EUR) per well.
QI Workflow to Identify Sweet Spots in the Unconventional Tight Gas Amin Play in North Oman
Authors: Scholten-Vissinga Marianne , Busaidi Talal
Published: January 2013

As conventional hydrocarbon plays have become highly mature after more than fifty years of exploration, Petroleum Development Oman LLC (PDO) is increasingly focusing towards unconventional plays. The Amin gas play is an example of such a play. The play concept consists of high pressure and high temperature alluvial sandstone reservoir with a very high netto-gross (N/G) but relatively low porosity and permeability. Due to these properties, the reservoir is classified as a tight reservoir.

Several wells in North Oman have encountered Amin reservoir showing low permeability and overpressures. One of the key wells within the area of interest has encountered high overpressures with good porosity and gas pay. These findings have triggered a quantitative interpretation (QI) study to pursue a possible correlation between seismically derived properties such as acoustic impedance or velocity with overpressures and/or good porosity to pinpoint sweet spots for drilling.

The QI study was split into two parts: Phase 1 consists of an amplitude versus angle (AVA) forward modelling including cross plotting of the rock properties and Phase 2 comprises an AVA inversion. The purpose of Phase 1 was to assess the feasibility of predicting reservoir quality or/and pore pressure by integrating well log data, VSP's and seismic data. The results from this phase were encouraging and it was decided to proceed with the AVA inversion.

The AVA inversion was carried out on the state of the art wide azimuth seismic data that was acquired in 2009. Using the results from the inversion and the knowledge obtained from Phase 1 enables us to identify sweet spots for future exploration drilling. In this paper the QI workflow is described which has been applied to identify sweet spots for this tight gas play. After this study was completed one additional well was drilled and is used as a blind test well.

The main conclusions from this study are that porosity variations at Amin level can be related to acoustic impedance at well resolution and at seismic resolution. AVA behavior shows that "higher" porosities in Amin give an increase in amplitude with increasing angle while "low" porosities show a polarity flip. Due to the limited availability of well data and their clustered distribution in the south-east corner of the survey, the inversion results are heavily biased by the derived low frequency model. Hence, only a porosity map and no volume has been calculated and is used to guide the porosity distribution in the static model.
Can Shale-Like Stimulations Unlock the Potential of Extremely Low Permeability Tight Gas Reservoirs?
Authors: Owolabi O. O. , Volz R. F. , Smith P. S.
Published: January 2013

Horizontal drilling and multi-stage fracturing has sky-rocketed the economic development of ultra-low permeability shale gas resources in North America. The same technology has the potential to be applied to extremely low permeability tight gas (sandstone) reservoirs.

In this paper, we discuss the results of evaluating if we can successfully apply shale-like stimulations in developing and improving the performance of extremely low permeability tight gas reservoirs. The focus of the study is on doing sensitivity model runs to investigate the effects of reservoir permeability, drainage area, fracture surface area, and fracture conductivity on both initial and long term gas production rates, using single well simulation models for a generic tight, dry gas reservoir. The study compared transverse multiple fractures in a horizontal well with 40, 20, 10, and 5 hydraulic fractures, for permeabilities from 1 mD down to 1 nD, and for drainage areas of 80 to 1,275 acres. The impact of fracture conductivities and fracture half-lengths on gas production was also assessed.

A typical horizontal tight gas completion has a lateral length of 2,500 ft to 3,500 ft with 5 to 7 fracture stimulation stages using open-hole completion style system. The results from this study show that there is potential for improving well economics by targeting more fracture initiation points similar to that of shale gas wells, when permeability of the tight gas reservoir is between 0.1 µD to 10 µD. The findings can be used not only to design better tight gas wells, but also helps in understanding the fundamental behavior of the low quality tight gas production system. In conclusion, this paper clearly illustrates that in extremely low permeability tight gas reservoirs, horizontal wellbores with shale-like stimulation programs may be the only robust option for achieving commercial gas production rates.
Adopting North American, Multi-stage Fracturing and Horizontal Completion Technologies Starts to Unlock the Amin Tight Gas Formation in the Sultanate of Oman
Authors: Robert Clark , Kevin Mullen , Stevanus Kurniadi
Published: January 2013

The careful planning and successful execution of a multi-stage fracture stimulation completion in one of the first horizontal wells drilled in the Amin Formation instigated a step change in initial production rate and long term deliverability from this tight gas sandstone reservoir in North Central Oman.

The field was discovered in 1993 but remained undeveloped due to low deliverability from single-stage hydraulic fracturing treatments. Previous vertical Amin completions, though intriguing, failed to deliver satisfactory production rates. Hydraulic fracturing stimulation technology is critical to achieving commercial rates in tight gas formations. The operator and service company worked as a team, modeling the fracturing program after North American practices, prescribing a novel approach for the Sultanate of Oman.

The vertical completion profile was changed to horizontal multi-stage fracturing, to increase reservoir contact. North American unconventional reservoir stimulations were investigated by pumping cross-linked gel, slick water, and hybrid fracs across six stages along the horizontal section. Several reservoir access options were tested to evaluate fracture initiation points including sliding sleeve, jet perforating, and abrasive jetting. Various well intervention strategies and zonal isolation techniques were also deployed. Extensive cased-hole logging was employed to evaluate the effectiveness of each stage.

A full range of integrated surveillance, including open-hole characterization, production logs, and BHP monitoring was used to evaluate formation behavior, fracturing effectiveness, and intervention activities, achieving optimum operational and production results for potential application to full field development.

Adopting best practices from other regions and integrating comprehensive surveillance data is helping to unlock the potential of the Amin tight gas reservoir. The KZN-F well is used as a case study throughout this paper.
Field Cases of Hydraulic Fracture Stimulation Diagnostics Using Fiber Optic Distributed Acoustic Sensing (DAS) Measurements and Analyses
Authors: Molenaar Mathieu M. , Cox Barbara E.
Published: January 2013

Deciding on the optimum spacing between fractures and selecting the optimum fracture treatment parameters is a key challenge in designing the hydraulic fracture stimulations of Unconventional Gas and Liquid Rich Shale (UGLRS) wells.

To make those decisions more effectively and more rapidly, (downhole) hydraulic fracture diagnostic tools can be used which provide a better understanding of how and where fractures initiate and what the distribution of fluid and proppant volume is downhole. One emerging technology, fiber optic distributed acoustic sensing (DAS) has the potential of providing such key diagnostic insights during hydraulic fracturing operations in real-time.

This paper describes some of the background technology and presents the results of several hydraulic fracture stimulation (HFS) diagnostic case studies. The results illustrate how DAS has been used to perform real-time monitoring for both open-hole multi-stage fracturing and "Cemented Plug & Perf Completions". DAS has provided valuable insight as to the stimulation effectiveness. The technique has also provided insights into effective zonal isolation when using mechanical isolation during the hydraulic-fracturing process that would otherwise not have been possible. It also complements other HFS diagnostic technologies (e.g. tracers, micro-seismic, distributed temperature sensing (DTS), production logs (PLT)).

DAS monitoring of hydraulic fracture stimulation can help accelerate the learning curve and drive performance improvements. Installation of fiber optic cables early in a field's life or when entering a new geological/geo-mechanical situation can allow for accelerated optimization of future wells.
A Cost Effective Way to Boost Production from Tight Oil and Gas Fields Using Surface Jet Pump Systems
Authors: Sarshar Sacha , Beg Najam
Published: January 2013

Tight oil and gas fields suffer from poor permeability and in most cases fragmentation of reservoir. As the reservoir pressure drops and water-cut increases, production from these fields becomes even more restricted. There are a number of techniques under IOR and EOR to maintain production and increase total recovery from these fields. These techniques involve major capital investments and involve some risks on the extent of benefits gained.

The use of surface jet pumps (SJPs) is a simple and cost effective way to maintain or boost production from many low pressure (LP) wells. This paper describes the key features of the SJP systems and their wide range of applications. A number of field examples, worldwide, are presented and in each case the benefits are highlighted. Payback period for the SJPs is short, a matter of a few weeks to a few months from the added revenue.

SJPs can operate cost effectively in conjunction with IOR and EOR techniques and artificial lift solutions in both oil and gas production applications. The use of SJPs is the simplest and least costly solution to maintain production and to extend the life of many wells. They are particularly beneficial for stranded satellite wells where other solutions are not cost effective because of their complexity, or the need for electric power, or continuous manning of the station. They offer other benefits such as de-bottlenecking compressors, eliminating intermediate compressors and prevention of flaring LP gas.
Subharmonic functions in sub-Riemannian settings
Authors: Bonfiglioli Andrea , Lanconelli Ermanno
Published: January 2013

In this paper we furnish mean value characterizations for subharmonic functions related to linear second order partial differential operators with nonnegative characteristic form, possessing a well-behaved fundamental solution

\Gamma

. These characterizations are based on suitable average operators on the level sets of

\Gamma

. Asymptotic characterizations are also considered, extending classical results of Blaschke, Privaloff, Radó, Beckenbach, Reade and Saks. We analyze as well the notion of subharmonic function in the weak sense of distributions, and we show how to approximate subharmonic functions by smooth ones. The classes of operators involved are wide enough to comprise, as very special cases, the sub-Laplacians on Carnot groups. The results presented here generalize and carry forward former results of the authors in [6, 8].
Welschinger invariants of small non-toric Del Pezzo surfaces
Authors: Itenberg Ilia , Kharlamov Viatcheslav , Shustin Eugenii
Published: January 2013

We give a recursive formula for purely real Welschinger invariants of the following real Del Pezzo surfaces: the projective plane blown up at

q

real and

s \leq 1

pairs of conjugate imaginary points, where

q+2s\le 5

, and the real quadric blown up at

s \leq 1

pairs of conjugate imaginary points and having non-empty real part. The formula is similar to Vakil's recursive formula [22] for Gromov–Witten invariants of these surfaces and generalizes our recursive formula [12] for purely real Welschinger invariants of real toric Del Pezzo surfaces. As a consequence, we prove the positivity of the Welschinger invariants under consideration and their logarithmic asymptotic equivalence to genus zero Gromov–Witten invariants.
Antifungal Studies of Selected Essential Oils and a Commercial Formulation against Botrytis Cinerea
Authors: Adebayo Oyeboade , Dang Thao , Bélanger André , Khanizadeh Shahrokh
Published: January 2013

Growing concerns about food safety and environmental protection have created a need for new and safe plant disease control strategies. The aim of this study was to find an alternative to synthetic fungicides currently used in the control of the devastating fungal pathogen Botrytis cinerea Pers., the causal agent of grey mould disease of strawberry (Fragariaananassa Duch). The antifungal activity of the essential oils of Origanumvulgare L., Monardadidyma L. and of a commercial formulation of thyme oil (Gloves Off®) was investigated against B. cinerea and compared with controls. Contact phase effects of different concentrations of the essential oils and commercial formulation were found to inhibit the growth of B. cinerea in a dose dependent manner. Complete growth inhibition of the pathogen was recorded at 200 µg/ml of ‘Gloves Off®’. The mycelial growth of the pathogen was significantly reduced at the highest concentration of the essential oils of O. vulgare and M. didyma tested, which was 51.2 µg/ml. Spore germination and germ tube elongation were also inhibited by the essential oils and Gloves Off®. Light microscopic observations revealed that the essential oils caused morphological degenerations, such as cytoplasmic coagulation, hyphal shrivelling and protoplast leakage of the fungal hyphae. The essential oils of O. vulgare L. and M. didyma L. are promising, antifungal agents against B. cinereasimilar to the commercial formulation ‘Gloves Off®’.
Aging obviates sex‐specific physiological responses to exercise
Authors: Deschenes Michael R. , Taylor Jessica L. , Mangis Katherine A.
Published: January 2013

Objectives

Both sex and aging have been shown to affect physiological responses to exercise. The aim of the present investigation was to determine whether aging impacted the sex‐specific nature of physiological responses to exercise commonly noted among young adults.

Methods

Ten aged men (69.0 ± 1.7 years; mean ± SE) and 10 aged women (71.6 ± 1.3 years) reporting similar levels of habitual physical activity performed a 30‐min exercise session at 60–65% of their predetermined peak oxygen uptake. Cardiovascular, thermoregulatory, and metabolic variables were assessed before exercise, at the 15th and 30th min of exercise, and at 5 and 15 min into a passive postexercise recovery period. Variables of interest were statistically analyzed via two‐way analysis of variance with repeated measures; significance was set at P < 0.05.

Results

Significant effects of time (i.e., exercise) for each physiological variable of interest were identified, but not once was a significant effect of group (i.e., sex) detected.

Conclusions

Exercise‐induced physiological responses to prolonged, moderate intensity exercise were similar among aged men and aged women. This evidence that the sexually dimorphic nature of physiological responses to exercise is obviated with age should be taken into account when prescribing health‐related exercise training programs for older individuals. Am. J. Hum. Biol. 25:215–221, 2013. © 2013 Wiley Periodicals, Inc.
Endocrinological issues and hormonal manipulation in children and men with Klinefelter syndrome
Authors: Wosnitzer Matthew S. , Paduch Darius A.
Published: January 2013

47, XXY or Klinefelter syndrome (KS), the most common chromosomal aberration in males, is characterized by either absolute or relative hypogonadism with frequent decline in serum testosterone (T) following the onset of puberty. Decreased T levels are the result of testicular dysfunction with decrease in size of Leydig cells, and loss of germs and Sertoli cells leading to tubular hyalinization. Increase in estradiol results from over‐expression of aromatase CYP19. Deficient androgen production and observed varied response of end‐organs to T leads to delayed progression of puberty with decreased facial/body hair, poor muscle development, osteoporosis, and gynecomastia. It is possible that hypogonadism and excessive estradiol production contribute to emotional and social immaturity, and specific learning disabilities in KS. Based on the authors' experience and literature review, early fertility preservation and hormonal supplementation may normalize pubertal development, prevent metabolic sequelae of hypogonadism, and have a positive effect on academic and social development. No randomized clinical trials are available studying the effects of T supplementation on reproductive or cognitive issues in KS. Aggressive T supplementation (topical gel) and selective use of aromatase inhibitors may be considered at the onset of puberty with careful follow‐up and titration to reach age‐specific high‐normal physiologic serum values. The decision to institute hormonal therapy should be part of a multidisciplinary approach including physical, speech, behavioral, and occupational therapy. © 2013 Wiley Periodicals, Inc.
Sexual differentiation of the brain in man and animals: Of relevance to Klinefelter syndrome?
Authors: McCarthy Margaret M.
Published: January 2013

The developing brain is highly sensitive to the organizing effects of steroids of gonadal origin in a process referred to as sexual differentiation. Early hormone effects prime the brain for adult sensitivity to the appropriate hormonal milieu, maximizing reproductive fitness via coordinated physiology and behavior. Animal models, in particular rodents, have provided insight into general principles and the cellular and molecular mechanisms of brain differentiation. Cellular endpoints influenced by steroids in the developing brain include neurogenesis, migration, apoptosis, dendritic growth, and synaptic patterning. Important roles for prostaglandins, endocanabinoids, and epigenetics are among the many cellular mediators of hormonal organization. Transference of general principles of brain sexual differentiation to humans relies on observations of individuals with genetic anomalies that either increase or decrease hormone exposure and sensitivity. The physiology and behavior of individuals with XXY (Klinefelter syndrome) has not been considered in the context of sexual differentiation of the brain, most likely due to the delay in diagnoses and highly variable presentation. The behavioral phenotype and impairments in the domains of speech and language that are characteristic of individuals with XXY is consistent with the reduced androgen production associated with the syndrome. Hormone replacement appears effective in restoring some deficits and impact may be further improved by increased understanding of the hormonally mediated sexual differentiation of the brain. © 2013 Wiley Periodicals, Inc.
Neurocognitive variance and neurological underpinnings of the X and Y chromosomal variations
Authors: Gropman Andrea , Samango‐Sprouse Carole A.
Published: January 2013

X and Y chromosomal variations including tetrasomy and pentasomy conditions are rare and occur in 1:18,000–1:100,000 male births. The most common sex chromosome aneuploidy is 47, XXY for which there is a rich literature delineating the physical and neurobehavioral phenotype. Although the more complex chromosome aneuploidies 48, XXYY, 48, XXXY, and 49, XXXXY are often compared with 47, XXY (Klinefelter syndrome) because of shared features including tall stature and hypergonadotropic hypogonadism, there is a wider spectrum of physical and cognitive abilities that have recently been delineated. The phenotypic presentation of the boys with more severe aneuploidy shares some characteristics with 47, XXY, but there are also other unique and distinctive features. Previously unappreciated intact nonverbal skills have been demonstrated in association with severe developmental dyspraxia. MRI findings of white matter hyperintensities may underlie cognitive deficits and deserve further study. This report discusses what is known about clinical variability in the XY syndromes collectively evaluated through careful multidisciplinary clinical evaluation including the clinical and neurobehavioral aspects of these conditions. Variability in clinical and cognitive functioning may reflect skewed X inactivation, mosaicism, or epigenetic factors that warrant further investigation. © 2013 Wiley Periodicals, Inc.
Coordination structures of Mg2+ and Ca2+ in three types of tobacco calmodulins in solution: Fourier‐transform infrared spectroscopic studies of side‐chain COO− groups
Authors: Suzuki Nanao , Imai Lica Fabiana , Kato Yusuke , Nagata Koji , Ohashi Yuko , Kuchitsu Kazuyuki , Tanokura Masaru , Sakamoto Akira , Nara Masayuki , Nakano Minoru , Yonezawa Naoto
Published: January 2013

Calmodulin (CaM) is a Ca2+‐binding protein that regulates a number of fundamental cellular activities. Nicotiana tabacum CaM (NtCaM) comprises 13 genes classified into three types, among which gene expression and target enzyme activation differ. We performed Fourier‐transform infrared spectroscopy to compare the secondary and coordination structures of Mg2+ and Ca2+ among NtCaM1, NtCaM3, and NtCaM13 as representatives of the three types of NtCaMs. Data suggested that NtCaM13 has a different secondary structure due to the weak β‐strand bands and the weak 1661 cm−1 band. Coordination structures of Mg2+ of NtCaM3 and NtCaM13 were similar but different from that of NtCaM1, while the Ca2+‐binding manner was similar among the three CaMs. The amplitude differences of the band at 1554–1550 cm−1 obtained by second‐derivative spectra indicated that the intensity change of the band of NtCaM13 was smaller in response to [Ca2+] increases under low [Ca2+] conditions than were those of NtCaM1 and NtCaM3, while the intensity reached the same level under high [Ca2+]. Therefore, NtCaM13 has a characteristic secondary structure and specific Mg2+‐binding manner and needs higher [Ca2+] for bidentate Ca2+ coordination of 12th Glu in EF‐hand motifs. The Ca2+‐binding mechanisms of the EF‐hand motifs of the three CaMs are similar; however, the cation‐dependent conformational change in NtCaM13 is unique among the three NtCaMs. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 472–483, 2013.
Bioinspired molecular adhesive for water‐resistant oxygen indicator films
Authors: Vu Chau Hai Thai , Won Keehoon
Published: January 2013

Mussels can attach themselves to nearly all types of hard surfaces in wet environments. Such attractive adhesive ability of mussels is believed to rely on the amino acid composition of proteins found near the plaque–substrate interface. Dopamine (DA) is identified as a simplified mimic of mussel proteins, which are rich in 3,4‐dihydroxy‐l‐phenylalanine and lysine, because it contains both catechol and amine functional groups. In this work, we have first applied this bioinspired adhesive to tackle a dye leaching problem of colorimetric oxygen indicator films, which are widely used to ensure the absence of oxygen inside the package of oxygen‐sensitive materials. Simple immersion of packaging films into a DA solution resulted in poly(DA) deposition, decreasing the water contact angle of the films from 105° to 65°. The poly(DA) coating could reduce the thionine leakage of the UV‐activated oxygen indicator film. The effects of poly(DA) coating were found to be dependent on the DA solution pH, the coating time, and the DA concentration. The film resistant to dye leaching lost its dye color by 5 min UVB irradiation and regained the color in the presence of oxygen, demonstrating that it functioned successfully as UV‐activated oxygen indicators. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 513–519, 2013
A CHO cell line engineered to express XBP1 and ERO1‐Lα has increased levels of transient protein expression
Authors: Cain Katharine , Peters Shirley , Hailu Hanna , Sweeney Bernie , Stephens Paul , Heads James , Sarkar Kaushik , Ventom Andy , Page Catherine , Dickson Alan
Published: January 2013

Transient gene expression (TGE) systems currently provide rapid and scalable (up to 100 L) methods for generating multigram quantities of recombinant heterologous proteins. Product titers of up to 1 g/L have been demonstrated in HEK293 cells but reported yields from Chinese hamster ovary (CHO) cells are lower at ∼300 mg/L. We report on the establishment of an engineered CHOS cell line, which has been developed for TGE. This cell line has been engineered to express both X‐box binding protein (XBP‐1S) and endoplasmic reticulum oxidoreductase (ERO1‐Lα) and has been named CHOS‐XE. CHOS‐XE cells produced increased antibody (MAb) yields (5.3– 6.2 fold) in comparison to CHOS cells. Product quality was unchanged as assessed by size, charge, propensity to aggregate, major glycosylation species, and thermal stability. To further develop and test this TGE system, five commercial media were assessed, and one was shown to offer the greatest increase in antibody yields. With the addition of a commercial feed, MAb titers reached 875 mg/L. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:697–706, 2013
Design of growth‐dependent biosensors based on destabilized GFP for the detection of physiological behavior of Escherichia coli in heterogeneous bioreactors
Authors: Han Shanshan , Delvigne Frank , Brognaux Alison , Charbon Gitte E. , Sørensen Søren J
Published: January 2013

In this work, we present the design and characterization of Green Fluorescent Protein (GFP)‐based reporter systems designed to describe cellular activity in “complex,” heterogeneous bioreactors. The reporter systems consist of Escherichia coli strains carrying growth dependent promoters fused to genes expressing stable and unstable variants of GFP, respectively. The response of Escherichia coli cells to transient exposure to glucose was studied in a two‐compartment scale down bioreactor (SDR) consisting of a well‐stirred tank reactor (STR) connected to a plug‐flow reactor (PFR). Such a SDR system is employed to mimic the situation of high glucose concentration and oxygen limitation that often encountered in large‐scale, fed‐batch bioreactors and the response of E. coli was simulated by continuously pumping microbial cells from STR to the PFR. We found that repeated addition of concentrated glucose pulses with varied frequency at the entrance of the PFR had consequences on strain physiological behavior. The GFP expressions were significantly marked after 10 h of cultivation in STR (control reactor) and SDR, whereas, growth rates were rather similar. Additional experiments in chemostat with programmed glucose perturbation suggested that the activities of the promoters were linked with the substrate limitation signal. Taken together with immunoblot analysis, we suppose protein leakage is responsible for the overexpression of fis and the related promoters, such as rrnB in this case study, but additional works are required in order to confirm this relationship. This investigation is useful for a better understanding of the fast dynamic phenomena occurring in heterogeneous large‐scale bioreactors. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 553–563, 2013
Triple IVC: A combination of periureteral venous ring and left IVC
Authors: Paik Nam Chull
Published: January 2013

Variations of the inferior vena cava (IVC) are clinically silent and most often diagnosed incidentally when imaging for other reasons. However, they may have significant clinical implications during retroperitoneal surgery, venous intervention, or differential imaging diagnosis. This article describes a case of triple IVC, discovered on a lumbar CT and MRI scan during an evaluation of back pain. Clin. Anat. 26:1002–1005, 2013. © 2013 Wiley Periodicals, Inc.
The vascular collar of the ilium— Three‐dimensional evaluation of the dominant nutrient foramen
Authors: Cunningham Craig A. , Black Sue M.
Published: January 2013

Nutrient arteries are the predominant blood supply to endochondral bones and are particularly important during the early stages of endochondral ossification and the active growth period. These nutrient vessels traverse the periosteal shell of a developing bone to invade the disintegrating cartilage matrix and bring about endochondral bone formation. This results in the formation of a nutrient foramen which is retained as the vascular conduit between the exterior and interior of the bone. This study examined the dominant nutrient foramen of the neonatal ilium using high resolution micro‐computed (micro‐CT) tomography. Three‐dimensional reconstruction of micro‐CT data consistently demonstrated the presence of a distinctive, yet poorly reported, collar of bone extending into the trabecular cavity beyond the endosteum. This study proposes that this collar of bone may have formed in response to osteogenic signaling from approximated arterial vasculature. Additionally, it is suggested that the formation of this collar may act as a protective mechanism to the dominant nutrient vessel and as a potential biomechanical anchor for surrounding trabeculae, aiding to increase the biomechanical competency around the area of the foramen. The documentation of this osteological structure is important from a clinical perspective to prevent the misinterpretation of fracturing and pathology on plain plate radiographs and clinical computed tomography scans. Clin. Anat., 2013. © 2013 Wiley Periodicals, Inc.
Synthesis and Characterization of Conformationally Rigid Chiral Pyridine–N‐Heterocyclic Carbene‐Based Palladacycles with an Unexpected Pd–N Bond Cleavage
Authors: Ng Kim Hong , Li Yongxin , Tan Wei Xian , Chiang Minyi , Pullarkat Sumod A.
Published: January 2013

The versatility of a previously developed method for the synthesis of chiral carbene‐based palladacycles is demonstrated through the synthesis of two new chiral pyridine‐functionalized N‐heterocyclic carbene palladacycles with different wingtip groups. The efficiency in their resolution with different counter anions and different chiral amino acid salt auxiliaries has been studied. The absolute stereochemistries of all the chiral compounds were confirmed by single crystal X‐ray crystallography. An unexpected Pd–N bond cleavage that resulted in the racemization of the α‐carbon center in these complexes has also been investigated. Chirality 25:149–159, 2013. © 2013 Wiley Periodicals, Inc.