bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of supplementary buccal infiltrations and intraligamentary injections to inferior alveolar nerve blocks in mandibular first molars with asymptomatic irreversible pulpitis: a randomized controlled trial
Authors: Parirokh M. , Sadr S. , Nakhaee N. , Abbott P. V. , Askarifard S.
Published: December 2013

Aim

This randomized double‐blinded controlled trial was performed to compare the efficacy of inferior alveolar nerve block (IANB) injection for mandibular first molar teeth with irreversible pulpitis with or without supplementary buccal infiltration and intraligamentary injection.

Methodology

Eighty‐two patients with asymptomatic irreversible pulpitis received either a combination of intraligamentary injection + buccal infiltration+ IANB or with traditional IANB injection in mandibular first molar teeth with irreversible pulpitis. Each patient recorded their pain score on a Heft–Parker visual analogue scale before commencing treatment, in response to a cold test 15 min after the designated anaesthetic injection, during access cavity preparation and during root canal instrumentation. No or mild pain at any stage was considered a success. Data were analysed by chi‐square test.

Results

At the final stage of treatment, 69 of the 82 patients were eligible to be included in the study. No significant difference was found between age (P = 0.569) and gender (P = 0.570) amongst the patients in the two groups. The success rate of anaesthesia in the IANB and the combination groups were 22% and 58%, respectively. The success rate of anaesthesia in the combination group was significantly higher than the traditional IANB injection (P = 0.003).

Conclusion

A combination of anaesthetic techniques can improve the success rate of anaesthesia for mandibular first molar teeth with irreversible pulpitis.
Estimation of inbreeding and effective population size of full‐blood wagyu cattle registered with the American Wagyu Cattle Association
Authors: Scraggs E. , Zanella R. , Wojtowicz A. , Taylor J.F. , Gaskins C.T. , Reeves J.J. , de Avila J.M. , Neibergs H.L.
Published: December 2013

The objective of this research was to examine the population structure of full‐blood (100%) Wagyu cattle registered in the United States with the American Wagyu Association, with the aim of estimating and comparing the levels of inbreeding from both pedigree and genotypic data. A total of 4132 full‐blood Wagyu cattle pedigrees were assessed and used to compute the inbreeding coefficients (FIT and FST) and the effective population size (Ne) from pedigree data for the period 1994 to 2011. In addition to pedigree analysis, 47 full‐blood Wagyu cattle representing eight prominent sire lines in the American Wagyu cattle population were genotyped using the Illumina BovineSNP50 BeadChip. Genotypic data were then used to estimate genomic inbreeding coefficients (FROH) by calculating runs of homozygosity. The mean inbreeding coefficient based on the pedigree data was estimated at 4.80%. The effective population size averaged 17 between the years 1994 and 2011 with an increase of 42.9 in 2000 and a drop of 1.8 in 2011. Examination of the runs of homozygosity revealed that the 47 Wagyu cattle from the eight prominent sire lines had a mean genomic inbreeding coefficient (FROH) estimated at 9.08% compared to a mean inbreeding coefficient based on pedigree data of 4.8%. These data suggest that the mean genotype inbreeding coefficient of full‐blood Wagyu cattle exceeds the inbreeding coefficient identified by pedigree. Inbreeding has increased slowly at a rate of 0.03% per year over the past 17 years. Wagyu breeders should continue to utilize many sires from divergent lines and consider outcrossing to other breeds to enhance genetic diversity and minimize the adverse effects of inbreeding in Wagyu.
Amoebophrya spp. from the Bloom‐forming Dinoflagellate Cochlodinium polykrikoides: Parasites not Nested in the “Amoebophrya ceratii Complex”
Authors: Kim Sunju , Park Myung Gil
Published: December 2013

Members of Amoebophrya ceratii complex are known to infect a number of free‐living dinoflagellates including harmful algal bloom species. In August and October 2012, Amoebophrya infections during two bloom events of the dinoflagellate Cochlodinium polykrikoides were observed along southern coastal waters of Korea. Microscopic observations and molecular data revealed that two different Amoebophrya parasites infected the same host species. In addition, while one developed in the host's nucleus, the other in the host's cytoplasm. Phylogenetic analyses showed that the two parasites were not nested in the previously recognized “Amoebophrya ceratii complex clade”, which contained sequences of parasites infecting numerous dinoflagellate species. Instead, they branched as sister taxa to the isolate (possibly Amoebophrya) from radiolarians Hexacontium gigantheum. Our result indicates that the two Amoebophrya parasites infecting C. polykrikoides may be different species from those inside the “complex.”
Experiences of Family Therapists Working with Families in a Transitional Homeless Community
Authors: Harris‐McKoy DeAnna E. , Woods Sarah B. , Brantley Cicely W. , Farineau Heather M.
Published: December 2013

The purpose of this study was to explore the experiences and observations of marriage and family therapists (MFTs) conducting an empirically supported parenting program at a transitional homeless community. A diary method was used in recording five MFTs' observations and reactions to implementing the psychoeducational groups. Fifty‐one recordings were collected from three different parenting groups over the course of 20 weeks. Constant comparative method was used to identify themes related to MFTs' experiences of conducting the parenting program. These themes included the needs of at‐risk families, confidentiality, and role ambivalence and boundary ambiguity. We provide recommendations for best practices and an example of therapists' decision‐making process using Kitchener's (1984) model.
A Bowen Family Systems Model of Generalized Anxiety Disorder and Romantic Relationship Distress
Authors: Priest Jacob B.
Published: December 2013

Many individuals with generalized anxiety disorder (GAD) do not respond well to currently available treatments. Moreover, treatments are less effective when GAD is accompanied by romantic relationship distress. In order to develop effective treatments for GAD and relationship distress, it is necessary to conduct theory‐based research to identify links common to both GAD and romantic relationship distress. Drawing on Bowen's family systems theory, the roles of family abuse/violence and differentiation in GAD and romantic relationship distress were examined using existing data from the National Comorbidity Survey Replication (n = 2,312; 2005). As predicted, family abuse/violence was directly linked to both GAD and romantic relationship distress. Differentiation mediated the relationship between family abuse/violence and GAD, and partially mediated the relationship between family abuse/violence and romantic relationship distress. Findings suggest that current and past relationship processes may help maintain chronic anxiety and that Bowen's theory may be a useful framework for developing couple therapy treatment of GAD and romantic relationship distress.
Experiences faced by next of kin during their older family members’ transition into long‐term care in a Norwegian nursing home
Authors: Eika Marianne , Espnes Geir Arild , Söderhamn Olle , Hvalvik Sigrun
Published: December 2013

Aims and objectives

To describe and explore experiences of next of kin during the older persons’ transition into long‐term care.

Background

Moving into long‐term care is a challenge for both resident and next of kin. Next of kin experience transitions at the same time as they play significant parts in their family members’ transition into long‐term care placement.

Design

Constructivist hermeneutical design.

Methods

Ten next of kin to newly admitted eight residents were recruited by purposeful sampling and interviewed. Periodic participant observation periods following new residents on arrival day and the first week after admission and some written documentation were the backdrops to the interviews.

Results

What happened prior to the long‐term care placement as well as what happened in the initial period of transition influenced the experiences of next of kin. Characteristics of their experiences were: ‘striving to handle the new situation’, ‘still feeling responsible’, and ‘maintaining dignity and continuity’.

Conclusions

Next of kin were unprepared for the transition and had little support from staff. Staff lacked awareness about next of kin's transition experiences. Their involvement with next of kin was unpredictable, and this added to the burdens of next of kin in this period.

Relevance to clinical practice

Knowledge about experiences of next of kin needs to be acknowledged among healthcare professionals. Health professionals need to pay attention to what happens across institutional borders within families as well as between staff and family members. Individual family members need support in this period of change.
Sexual function in women after urinary incontinence and/or pelvic organ prolapse surgery
Authors: Celik Dilek Bilgic , Kizilkaya Beji Nezihe , Yalcin Onay
Published: December 2013

Aims and Objectives

To determine how the sexual function is affected in women who underwent surgery for urinary incontinence and/or pelvic organ prolapse.

Design

The study was conducted as a descriptive and prospective research.

Background

Approximately 11·1% of the cases with pelvic organ prolapse or urinary incontinence require surgical intervention. Some authors report improved function after surgical correction of pelvic floor disorders, whereas others report deterioration of function.

Methods

The research was carried out with totally 116 patients in three groups of women who underwent surgery for urinary incontinence and/or pelvic organ prolapse. Sexual function and low urinary tract symptoms were assessed preoperatively and at six months postoperatively, with the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire 12 and Bristol Female Lower Urinary Tract Symptoms Scale.

Results

Prolapse/Urinary Incontinence Sexual Questionnaire‐12 total scores increased significantly, and sexual function improved at postoperative six months in all groups. In the evaluation of sexual function in each group at preoperative and postoperative six months, Prolapse/Urinary Incontinence Sexual Questionnaire‐12 scores of UI, and UI and POP were found to be increased significantly, while there was no change in sexual function in women in the pelvic organ prolapse surgery group at postoperative six months compared with preoperative period.

Conclusion

As a result, it was determined that lower urinary tract symptoms were improved and sexual function of women changed positively at six months after UI and/or POP surgery.

Relevance to clinical practice

It is important to provide counselling on potential development of postoperative sexual function and the possibility of impairment of sexual function for women undergoing UI and/or POP surgery.
Effect of implant‐supported prosthesis on the bite force and masticatory efficiency in subjects with shortened dental arches
Authors: Meena A. , Jain V. , Singh N. , Arora N. , Jha R.
Published: December 2013

The aim of the study was to assess changes in bite force and masticatory efficiency in shortened dental arch (SDA) subjects rehabilitated with implant‐supported restoration for 1st molar. Ten SDA subjects with bilaterally missing mandibular molars (experimental group) were recruited. In each subject, one tapered threaded implant was placed bilaterally in 1st mandibular molar region and restored. Masticatory efficiency was evaluated objectively by measuring the released dye from chewed raw carrots, with a ‘spectrophotometer’ at 530 nm preoperatively and at 3 months after restoration. Bite force was evaluated using ‘bite force measuring appliance’ preoperatively, at 6 weeks and at 3 months after restoration. Ten completely dentate‐matched subjects (in terms of age, sex, height and weight) acted as control. The results revealed that as compared with the control group, the experimental group showed significantly less (P < 0·05) mean maximum bite force at pre‐restoration and at 6 weeks after restoration. Although at 3 months the mean maximum bite force value was less than the control group but the mean difference was statistically insignificant. The mean difference of masticatory efficiency between control and experimental group was statistically significant (P < 0·05) before restoration, but was statistically insignificant at 3 months after restoration. Thus it was concluded that after the restoration of mandibular arch with implant‐supported prosthesis, both bite force and masticatory efficiency of all SDA subjects increased and were comparable to that of matched completely dentate subjects after 3 months.
Bean Yellow Mosaic Virus in Soybean from Argentina
Authors: Campos Ramón E. , Bejerman Nicolás , Nome Claudia , Laguna Irma G. , Rodríguez Pardina Patricia
Published: December 2013

An association of Bean yellow mosaic virus (BYMV), (genus Potyvirus), with yellow mosaic leaf symptoms on soybean in Argentina was determined by enzyme‐linked immunosorbent assay, a result confirmed by transmission electron microscopy and reverse transcription‐polymerase chain reaction using a degenerate primer targeting the C‐terminal region of BYMV′s NIb. The sequence analysis showed that the isolate had 80.6–91.6% identities with other BYMV isolates from different strain groups, indicating that it is a strain of BYMV.
NON‐STATIONARITY AND QUASI‐MAXIMUM LIKELIHOOD ESTIMATION ON A DOUBLE AUTOREGRESSIVE MODEL
Authors: Chen Min , Li Dong , Ling Shiqing
Published: December 2013

This article first studies the non‐stationarity of the first‐order double AR model, which is defined by the random recurrence equation , where γ0 > 0, α0 ≥ 0, and {ηt}is a sequence of i.i.d. symmetric random variables. It is shown that the double AR(1) model is explosive under the condition . Based on this, it is shown that the quasi‐maximum likelihood estimator of (φ0,α0) is consistent and asymptotically normal so that the unit root problem does not exist in the double AR(1) model. Simulation studies are carried out to assess the performance of the quasi‐maximum likelihood estimator in finite samples.
Bacterial taxa–area and distance–decay relationships in marine environments
Authors: Zinger L. , Boetius A. , Ramette A.
Published: December 2013

The taxa–area relationship (TAR) and the distance–decay relationship (DDR) both describe spatial turnover of taxa and are central patterns of biodiversity. Here, we compared TAR and DDR of bacterial communities across different marine realms and ecosystems at the global scale. To obtain reliable global estimates for both relationships, we quantified the poorly assessed effects of sequencing depth, rare taxa removal and number of sampling sites. Slope coefficients of bacterial TARs were within the range of those of plants and animals, whereas slope coefficients of bacterial DDR were much lower. Slope coefficients were mostly affected by removing rare taxa and by the number of sampling sites considered in the calculations. TAR and DDR slope coefficients were overestimated at sequencing depth <4000 sequences per sample. Noticeably, bacterial TAR and DDR patterns did not correlate with each other both within and across ecosystem types, suggesting that (i) TAR cannot be directly derived from DDR and (ii) TAR and DDR may be influenced by different ecological factors. Nevertheless, we found marine bacterial TAR and DDR to be steeper in ecosystems associated with high environmental heterogeneity or spatial isolation, namely marine sediments and coastal environments compared with pelagic ecosystems. Hence, our study provides information on macroecological patterns of marine bacteria, as well as methodological and conceptual insights, at a time when biodiversity surveys increasingly make use of high‐throughput sequencing technologies.
Adenosine Mapping for Adenosine‐Dependent Accessory Pathway Ablation
Authors: LAPAGE MARTIN J. , WALSH MICHAEL J. , REED JOHN H. , SAUL J. PHILIP
Published: December 2013

Background

This study describes the use of adenosine during ablation procedures to allow conduction through adenosine‐dependent accessory pathways (APs), which are inactive at the time of the procedure. The technique allows for successful mapping and ablation of these pathways.

Methods

Retrospective review of all patients undergoing AP ablation from 1998 to 2008 to identify patients with absent or intermittent AP conduction during electrophysiology study. Adenosine boluses were used to activate the AP for the purpose of mapping in each case.

Results

Adenosine mapping was utilized in seven patients. One patient had a concealed AP at baseline and six patients had manifest preexcitation at baseline but lost AP conduction during the case. Alternative methods of enhancing AP conduction were attempted in five patients, but failed. Acute ablation results included: four patients with complete elimination of AP conduction, two patients with AP conduction only with adenosine, and one patient with return of baseline preexcitation. Patients with residual antegrade conduction had right superior (anterior) septal APs considered too close to the atrioventricular conduction system for safe ablation. At median follow‐up of 2 years, all three patients with residual AP conduction had recurrence of supraventricular tachycardia; the remainder remained free of preexcitation and SVT.

Conclusion

Adenosine mapping is a useful technique for facilitating AP ablation when pathway conduction is absent or inconsistent, and may enhance conduction in mechanically inhibited or previously ablated APs. Recurrence of AP conduction only during adenosine administration is predictive of late recurrence.
Can Cardiac Resynchronization Therapy Improve Cognitive Function? A Systematic Review
Authors: PROIETTI RICCARDO , MANZONI GIAN MAURO , CRAVELLO LUCA , CASTELNUOVO GIANLUCA , BERNIER MARTIN LOUIS , ESSEBAG VIDAL
Published: December 2013

Introduction

Cognitive impairment (CI) comprises a measurable deficit of different cognitive domains (memory, attention, problem solving, and motor speed), and has a high prevalence among congestive heart failure (CHF) patients. Only a few pilot studies have investigated the effects of cardiac resynchronization therapy (CRT) on cognitive performance. The purpose of this systematic review is to outline and evaluate results of published studies that assess the impact of CRT on neuropsychological function in CHF.

Methods

Electronic databases were searched for articles containing the following terms: CRT, cognition, cognitive, and neurocognitive. A data extraction was performed according to our objective from each study. Effect sizes were computed using Hedges’ g. The within‐group formula was used for cohort studies with a pre‐post design, while the between‐group formula was used for studies that compared independent groups. Multiple outcomes were combined in domain‐specific synthetic scores as well as in a global score for each study, and a fixed‐effect model was used to estimate the summary effects.

Results

Only three studies met criteria for inclusion in the analysis. The results of these studies were discordant and methodological limitations were identified. The meta‐analysis of cognitive outcomes showed a nonsignificant overall effect (Hedges’ g = 0.131, 95% confidence interval: −0.16 to 0.422), while the summary effects on executive functioning and attention reached statistical significance (Hedges’ g = 0.374, 95% confidence interval: 0.085–0.662 and Hedges’ g = 0.343, 95% confidence interval: 0.051–0.635, respectively).

Conclusion

CI and related negative consequences have been largely documented in patients with heart failure but very few studies have assessed the plausible benefits of CRT on patients’ cognitive function. Despite the statistical significance of the domain‐specific pooled effects, their validity and clinical relevance is lacking due to methodological limitations.
Autonomic Neural Remodeling of the Pulmonary Vein‐Left Atrium Junction in a Prolonged Right Atrial Pacing Canine Model
Authors: ZHENG SHAOHUA , ZHANG YUJIAO , WANG ZHONGSU , LI ZHIYUAN , HOU XUJUAN , DUAN WENCHANG , HOU YINGLONG
Published: December 2013

Background

No evidence has been presented to show whether autonomic neural remodeling occurs in pulmonary vein‐left atrium (PV‐LA) junction and what an important role it may play in AF. This study aims to find out these issues in a prolonged rapid atrial pacing canine model.

Methods

Twelve healthy mongrel dogs were randomly divided into two groups, six in each: the paced group underwent rapid right atrial pacing at 400 beats per minute for 4 weeks, and the control group was not paced. The effective refractory period (ERP) of left superior pulmonary vein‐left atrium (LSPV‐LA) junction in all animals was determined immediately after 4 weeks. Tissues were removed from 1 cm around all PV‐LA junctions. Immunohistochemical staining and western blotting were performed to examine the expression of tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT).

Results

Compared with the control group, ERP of LSPV‐LA junction of the paced group was significantly shortened ([83.33 ± 16.33] ms vs [111.67 ± 20.41] ms, P < 0.05). Spontaneous atrial fibrillation developed in two animals in the paced group, but in none of the control group. Immunohistochemistry showed that the average density and heterogeneity of both TH‐ and ChAT‐positive nerves at LSPV‐LA junction in the paced group were significantly higher compared to the control group (P < 0.01). Western blotting showed that the expression of TH and ChAT at four PV‐LA junctions in the paced group also increased markedly compared with the control group (P < 0.01).

Conclusion

Autonomic neural remodeling did exist in PV‐LA junction after prolonged atrial pacing, which may contribute to the initiation of atrial fibrillation and be significant in its treatment by radiofrequency catheter ablation.
A Scale of Risk
Authors: Gardoni Paolo , Murphy Colleen
Published: December 2013

This article proposes a conceptual framework for ranking the relative gravity of diverse risks. This framework identifies the moral considerations that should inform the evaluation and comparison of diverse risks. A common definition of risk includes two dimensions: the probability of occurrence and the associated consequences of a set of hazardous scenarios. This article first expands this definition to include a third dimension: the source of a risk. The source of a risk refers to the agents involved in the creation or maintenance of a risk and captures a central moral concern about risks. Then, a scale of risk is proposed to categorize risks along a multidimensional ranking, based on a comparative evaluation of the consequences, probability, and source of a given risk. A risk is ranked higher on the scale the larger the consequences, the greater the probability, and the more morally culpable the source. The information from the proposed comparative evaluation of risks can inform the selection of priorities for risk mitigation.
Soil microbial diversity and activity in a Mediterranean olive orchard using sustainable agricultural practices
Authors: Sofo A. , Ciarfaglia A. , Scopa A. , Camele I. , Curci M. , Crecchio C. , Xiloyannis C. , Palese A. M.
Published: December 2013

Sustainable soil management of orchards can have positive effects on both soils and crop yields due to increases in microbial biomass, activity and complexity. The aim of this study was to investigate medium‐term effects (12 yr) of two different management practices termed ‘sustainable’ (ST) and ‘conventional’ (CT) on soil microbial composition and metabolic diversity of a rainfed mature olive orchard in Southern Italy. ST included no‐till, self‐seeding weeds (mainly graminaceous and leguminosae), and mulch derived from olive tree prunings, whilst CT was managed by frequent tillage and included severe pruning with residues removed from the orchard. Microbial analyses were carried out by culture‐dependent methods (microbial cultures and Biolog®). Molecular methods were used to confirm the identification by light microscopy of the isolates of fungi and Streptomyces. Significantly more culturable fungi and bacteria were found in ST than in CT. The number of fungal groups in ST was also significantly greater than in CT. Overall and substrate‐specific Biolog® metabolic diversity indices of microbial communities and soil enzyme activities were greater in ST. The results demonstrate that soil micro‐organisms respond positively to sustainable orchard management characterized by periodic applications of locally derived organic matter. This study confirms the need to encourage farmers with orchards in the Mediterranean basin to practise soil management based on organic matter inputs associated with zero tillage to improve soil functionality.
Fear of the perpetrator: a major reason why sexual assault victims delayed presenting at hospital
Authors: Adefolalu Adegoke O.
Published: December 2013

Objective

To identify the reasons for presentation of sexual assault more than 72 h after the incidents at Newcastle Hospital, South Africa.

Methods

A retrospective analysis of 534 medical records of victims seen between 2005 and 2009 at the hospital's sexual assault service centre.

Results

Overall, 219 (41%) of the victims presented at the hospital more than 72 h after the alleged sexual assault, mainly for fear of the perpetrator (37.4%). Females constituted 87%, and rape with vaginal penetration was the most common form of sexual assault reported (74%). Tests of significance showed a positive association between fear of the perpetrator and delayed presentation at hospital. Age under 9 years and being scared of what relatives would say about alleged sexual assault were also associated with delayed presentation.

Conclusions

Attention needs to be focused on educating society on the importance of reporting sexual assault incidents promptly in order for victims to benefit from appropriate medical treatment.
Seasonal and gestation stage associated differences in aflatoxin exposure in pregnant Gambian women
Authors: Castelino Jovita M. , Dominguez‐Salas Paula , Routledge Michael N. , Prentice Andrew M. , Moore Sophie E. , Hennig Branwen J. , Wild Christopher P. , Gong Yun Yun
Published: December 2013

Objective

Aflatoxin is known to cross the placental barrier and exposures in utero could influence genomic programming, foetal growth and development, resulting in long‐term health effects. We aimed to determine aflatoxin exposure in Gambian women at two stages of pregnancy and during the rainy and dry seasons.

Methods

We examined aflatoxin exposure in pregnant Gambian women at early (<16 weeks) and later (16 weeks onward) stages of pregnancy and at different times of the year, during the rainy (June to October 2009) or dry (November to May 2010) season, using aflatoxin–albumin adducts (AF‐alb).

Results

Mean AF‐alb was higher during the dry season than in the rainy season, in both early and later pregnancy although the difference was strongest in later pregnancy. There was a modest increase in AF‐alb in later than early pregnancy (geometric mean 41.8 vs. 34.5 pg/mg, P < 0.05), but this was restricted to the dry season when exposures were generally higher.

Conclusions

The study confirmed that Gambian pregnant women were exposed to aflatoxin throughout the pregnancy, with higher levels in the dry season. There was some evidence in the dry season that women in later pregnancy had higher AF‐alb levels than those in earlier pregnancy. Further research on the effects of exposure to this potent mutagen and carcinogen throughout pregnancy, including the epigenetic modification of foetal gene expression and impact on pre‐ and post‐natal growth and development, are merited.
The rhythms of life: what your body clock means to you!
Authors: Foster Russell G. , Kreitzman Leon
Published: December 2013

New Findings

What is the topic of this review?

24 h rhythms have been observed in plants, animals and humans since ancient times, but until recently little was known about how these rhythms are generated or regulated, and what happens to our health when these rhythms are disrupted.

What advances does it highlight?

24 h rhythms arise from the molecular interaction of key “clock genes”. This molecular clockwork is in turn adjusted to the external world by recently discovered photoreceptors within the eye. This new insight about our biology is having a major impact on both the understanding and treatment of multiple diseases, including mental illness.

Until we turned our nights into days and began to travel in aircraft across multiple time zones, we were largely unaware that we possess a ‘day within’ driven by an internal body clock. Yet the striking impairment of our abilities in the early hours of the morning soon reminds us that we are slaves to our biology. Our ability to perform mathematical calculations or other intellectual tasks between 04.00 and 06.00 h is worse than if we had consumed several shots of whisky and would be classified as legally drunk. Biological clocks drive or alter our sleep patterns, alertness, mood, physical strength, blood pressure and every other aspect of our physiology and behaviour. Our emerging understanding of how these 24 h rhythms are generated and regulated is not only one of the great success stories of modern biology, but is also informing many areas of human health. Sleep and circadian rhythm disruption (SCRD) is a feature shared by some of the most challenging diseases of our time, including neuropsychiatric illness and serious disorders of the eye. Sleep and circadian rhythm disruption is also commonly seen across many sectors of society, from teenagers to shift workers. We also now appreciate that SCRD is far more than feeling sleepy at an inappropriate time. It promotes multiple illnesses ranging across abnormal metabolism, heart disease, reduced immunity, increased stress and abnormal cognition and mood states. This short review considers how 24 h rhythms are generated and regulated, the consequences of working against our body clock and the emerging relationship between SCRD and mental illness.
Assessment of dynamic cerebral autoregulation and cerebrovascular CO2 reactivity in ageing by measurements of cerebral blood flow and cortical oxygenation
Authors: Oudegeest‐Sander Madelijn H. , van Beek Arenda H. E. A. , Abbink Karin , Olde Rikkert Marcel G. M. , Hopman Maria T. E. , Claassen Jurgen A. H. R.
Published: December 2013

New Findings

What is the central question in this study?

It is unknown to what extent increasing age influences the dynamic adaptations of cerebral blood flow velocity and cortical oxygenation in response to changes in blood pressure (cerebral autoregulation) and to changes in carbon dioxide (cerebrovascular CO2 reactivity).

What is the main finding and its importance?

We have shown that ageing up to 86 years is associated with an overall preservation of dynamic cerebral autoregulation and cerebrovascular CO2 reactivity, leading to a sufficiency of cerebral cortical oxygenation during daily life activities, despite the decrease in absolute cerebral blood flow velocity and increase in cerebrovascular resistance with advancing age.

With ageing, cerebral blood flow velocity (CBFV) decreases; however, to what extent dynamic cerebral autoregulation and cerebrovascular CO2 reactivity are influenced by ageing is unknown. The aim was to examine the dynamic responses of CBFV and cortical oxygenation to changes in blood pressure (BP) and arterial CO2 across different ages. Fifty‐eight participants in three age groups were included, as follows: young (n = 20, 24 ± 2 years old), elderly (n = 20, 66 ± 1 years old), and older elderly (n = 18, 78 ± 3 years old). The CBFV was measured using transcranial Doppler ultrasound, simultaneously with oxyhaemoglobin (O2Hb) using near‐infrared spectroscopy and beat‐to‐beat BP measurements using Finapres. Postural manoeuvres were performed to induce haemodynamic fluctuations. Cerebrovascular CO2 reactivity was tested with hyperventilation and CO2 inhalation. With age, CBFV decreased (young 59 ± 12 cm s−1, elderly 48 ± 7 cm s−1 and older elderly 42 ± 9 cm s−1, P < 0.05) and cerebrovascular resistance increased (1.46 ± 0.58, 1.81 ± 0.36 and 1.98 ± 0.52 mmHg cm−1 s−1, respectively, P < 0.05). Normalized gain (autoregulatory damping) increased with age for BP–CBFV (0.88 ± 0.18, 1.31 ± 0.30 and 1.06 ± 0.34, respectively, P < 0.05) and CBFV–O2Hb (0.10 ± 0.09, 0.12 ± 0.04 and 0.17 ± 0.08, respectively, P < 0.05) during the repeated sit–stand manoeuvre at 0.05 Hz. Even though the absolute changes in CBFV and cerebrovascular resistance index during the cerebrovascular CO2 reactivity were higher in the young group, the percentage changes in CBFV, cerebrovascular resistance index and O2Hb were similar in all age groups. In conclusion, there was no decline in dynamic cerebral autoregulation and cerebrovascular CO2 reactivity with increasing age up to 86 years. Despite the decrease in cerebral blood flow velocity and increase in cerebrovascular resistance with advancing age, CBFV and cortical oxygenation were not compromised in these elderly humans during manoeuvres that mimic daily life activities.
Phox2b‐expressing retrotrapezoid neurons and the integration of central and peripheral chemosensory control of breathing in conscious rats
Authors: Takakura Ana C. , Barna Bárbara F. , Cruz Josiane C. , Colombari Eduardo , Moreira Thiago S.
Published: December 2013

New Findings

What is the central question of this study?

This study was designed to investigate whether the Phox2b‐expressing neurons in the retrotrapezoid nucleus are important to breathing and chemoreflexes in conscious rats.

What is the main finding and its importance?

The high rate of destruction of a defined cell population (Phox2b+TH−) of the retrotrapezoid nucleus by the toxin suggests that the specialized connectivity of retrotrapezoid nucleus neurons, their glutamatergic nature and their relatively high sensitivity to CO2 are determinant factors in explaining their large contribution to the central and peripheral chemoreflexes.

Chemoreception is the classic mechanism by which the brain regulates breathing in response to changes in tissue CO2/H+. A brainstem region called the retrotrapezoid nucleus (RTN) contains a population of Phox2b‐expressing glutamatergic neurons that appear to function as important chemoreceptors. In the present study, we ask whether the destruction of a type of pH‐sensitive interneuron that expresses the transcription factor Phox2b and is non‐catecholaminergic (Phox2b+TH−) could affect breathing in conscious adult rats. The injection of substance P (1 nmol in a volume of 50 nl) into the RTN increased respiratory frequency, tidal volume, minute ventilation and mean arterial pressure. Bilateral injections of the toxin substance P conjugated with saporin (SSP–SAP) into the RTN destroyed Phox2b+TH− neurons but spared facial motoneurons, catecholaminergic and serotonergic neurons and the ventral respiratory column caudal to the facial motor nucleus. Bilateral inhibition of RTN neurons with SSP–SAP (0.6 ng in 30 nl) reduced resting ventilation and the increase in ventilation produced by hypercapnia (7% CO2) in conscious rats with or without peripheral chemoreceptors. In anaesthetized rats with bilateral lesions of around 90% of the Phox2b+TH− neurons, acute activation of the Bötzinger complex, the pre‐Bötzinger complex or the rostral ventral respiratory group with NMDA (5 pmol in 50 nl) elicited normal cardiorespiratory output. In conclusion, the destruction of the Phox2b+TH− neurons is a plausible cause of the respiratory deficits observed after injection of SSP–SAP into the RTN. Our results also suggest that RTN neurons activate facilitatory mechanisms important to the control of breathing in resting or hypercapnic conditions in conscious adult rats.
Developing the Fabrication Technique With Low Energy Consumption of Dye-Sensitized Solar Cells
Authors: Wu Ying-Yan , Chen Chien-Chih , Ting Chen-Ching
Published: December 2013

This article presents significant experimental data about the dye-sensitized nano solar cells (DSSCs) using new photoelectrode fabrication technique to achieve low energy consumption process purposes. The typical nano TiO2 solution preparation usually spends some hours for nano TiO2 particle dispersion with extremely high input ultrasonic energy. Moreover, a sintering process for adhesion enhancement often requires temperature over 500°C, which also results in very large energy consumption. This work develops a composite apparatus for nano TiO2 particle dispersion using ultrasonic dispersion with help of agitation to reduce the dispersion time and uses the conductive binder to replace the sintering process. The new developed fabrication process of the photoelectrode spends 30 mins with input power ca. 300 W for dispersion and 10 mins with 150°C for drying, which saves ca. 70% energy. The result shows that short-circuit density, open-circuit voltage, fill factor, and photoelectric conversion efficiency of the best DSSCs in this work are 3.04 mA/cm2, 0.80 V, 49%, and 1.18% respectively.
Optimization of the Flow Field of a Novel ARID Raceway (ARID-HV) for Algal Production
Authors: Xu Ben , Li Peiwen , Waller Peter
Published: December 2013

This paper addresses issues of flow field optimization for a water raceway which is used to grow algae for biofuels. An open channel raceway is the typical facility to grow algae in medium to large scales. The algae growth rate in a raceway is affected by conditions of temperature, nutrients, and sunlight intensity etc. These conditions are essentially associated with the fluid mixing in the flow field. Good flow mixing at low consumption of pumping power for the water flow is desirable for an economic algal growth facility. A novel design of an open channel raceway for medium- and large-scale algae growth field has been proposed by the authors previously, which is called High Velocity Algae Raceway Integrated Design (ARID-HV). Optimization analysis using CFD and experimental visualization has been applied to a table-sized ARID-HV test model with various geometries of dams and their spacing in the system. CFD results and flow visualization allow us to understand the flow mixing in the entire raceway. Data is also processed to show the statistics of the locations of ‘fluid particles’ at different height and time period during one flow path. Different flow field designs were thus compared quantitatively based on this statistics according to the understanding that the “tumbling times” of fluid particles at bottom/top of the water is tightly related to the growth rate of algae.
Performance of Rigid Porous Stratification Manifolds With Interpretation for Off-Design Operation
Authors: Wang Shuping , Davidson Jane H.
Published: December 2013

Thermal stratification of solar water storage tanks improves collector efficiency and provides higher quality energy to the user. A crucial aspect of maintaining stratification is preventing mixing in the tank, particularly during solar charging and hot water draws. An effective and simple approach to flow control is an internal stratification manifold. In this paper, the performance of the rigid porous manifold, which consists of a series of vertical hydraulic resistance elements placed within a perforated tube, is considered for charging operation. A 1-D model of the governing mass, momentum, and energy conservation equations is used to illustrate the procedure for designing a manifold and to explore its performance over a broad range of operating conditions expected in solar water storage tanks. A manifold performance indicator (MPI) is used to evaluate the effectiveness of the manifold relative to an inlet pipe positioned at the top of the tank. The rigid porous manifold improves the stratification in the tank over a wide range of operating conditions unless the inlet flow rate is significantly reduced from the design point.
Application of Mechanisms for the Control of Autoignition in High Power Internal Combustion Engine Fueled With Natural Gas
Authors: Duarte Forero Jorge , Amador Diaz German , Garcia Garcia Jesus , San Juan Mejia Marco , Corredor Martinez Lesme
Published: December 2013

In this paper, a thermodynamic model of a spark ignition internal combustion engine fueled with natural gas is developed in order to estimate the air-fuel-unburned gas temperature at before top dead center (BTDC). This temperature is used as controlled variable in a control loop in order to avoid the autoignition phenomena when the engine operates with a fuel with different methane number from the methane number requirement of the engine. The model formulation is based on a polytropic compression proccess whose coefficient was determined experimentally in a turbocharged internal combustion engine fueled with natural gas. To make feasible the use of differents gaseous fuels from natural gas, it was necessary to design two control strategies to avoid the knocking phenomenon and choose the best one. The ambient temperature is the disturbance considered, whose changes are significant in different places in the world. The first control strategy that was implemented is called “Robust”, which employs a conventional feedback control loop with a robust controller which is designed. The response of this control loop is compared to the response of the second control strategy called “Feedforward control”. The results obtained reveals that Feedforward control strategy has better performance than robust control strategy for this application. The control strategy and the model proposed will allow increase the range of application of gaseous fuels with low methane number (MN) leading to guarantee a safe running in internal combustion engines that currently are fueled with natural gas.
Assessment of the Performance of Various Airfoil Sections on Power Generation From a Wind Turbine Using the Blade Element Momentum Theory
Authors: Chen Xiaomin , Agarwal Ramesh
Published: December 2013

It is well established that the power generated by a Horizontal-Axis Wind Turbine (HAWT) is a function of the number of blades B, the tip speed ratio λ (blade tip speed/wind free stream velocity) and the lift to drag ratio (CL/CD) of the airfoil sections of the blade. The airfoil sections used in HAWT are generally thick airfoils such as the S, DU, FX, Flat-back and NACA 6-series of airfoils. These airfoils vary in (CL/CD) for a given B and λ, and therefore the power generated by HAWT for different blade airfoil sections will vary. The goal of this paper is to evaluate the effect of different airfoil sections on HAWT performance using the Blade Element Momentum (BEM) theory. In this study, we employ DU 91-W2-250, FX 66-S196-V1, NACA 64421, and Flat-back series of airfoils (FB-3500-0050, FB-3500-0875, and FB-3500-1750) and compare their performance with S809 airfoil used in NREL Phase II and III wind turbines; the lift and drag coefficient data for these airfoils sections are available. The output power of the turbine is calculated using these airfoil section blades for a given B and λ and is compared with the original NREL Phase II and Phase III turbines using S809 airfoil section. It is shown that by a suitable choice of airfoil section of HAWT blade, the power generated by the turbine can be significantly increased. Parametric studies are also conducted by varying the turbine rotor diameter.
Numerical Simulation of Geological Carbon Sequestration in Saline Aquifers: Three Case Studies
Authors: Zhang Zheming , Agarwal Ramesh
Published: December 2013

Geological carbon sequestration (GCS) is one of the most promising technologies to address the issue of excessive anthropogenic CO2 emissions in the atmosphere due to fossil fuel combustion for electricity generation. For GCS, the saline aquifer geological carbon sequestration is considered very attractive compared to other options because of their huge sequestration capacity in U.S. and other parts of the world. However, in order to fully exploit their potential, the injection strategies need to be investigated that can address the issues of both the CO2 storage efficiency and safety along with their economic feasibility. Numerical simulations can be used to determine these strategies before the deployment of full scale sequestration in saline aquifers. This paper presents the numerical simulations of CO2 sequestration in three large identified saline aquifers (Mt. Simon, Frio, Utsira) where the sequestration is currently underway or has recently been completed (in case of Frio). The numerical simulations are in acceptable agreement with the seismic data available for plume migration. The results of large scale history-matching simulation in Mt. Simon, Frio, and Utsira formations provide important insights in the uncertainties associated with the numerical modeling of saline aquifer GCS.
Computational Fluid Dynamics Modeling of Mixed Convection Flows in Building Enclosures
Authors: Kayne Alexander , Agarwal Ramesh
Published: December 2013

In recent years Computational Fluid Dynamics (CFD) simulations are increasingly used to model the air circulation and temperature environment inside the rooms of residential and office buildings to gain insight into the relative energy consumptions of various HVAC systems for cooling/heating for climate control and thermal comfort. This requires accurate simulation of turbulent flow and heat transfer for various types of ventilation systems using the Reynolds-Averaged Navier-Stokes (RANS) equations of fluid dynamics. Large Eddy Simulation (LES) or Direct Numerical Simulation (DNS) of Navier-Stokes equations is computationally intensive and expensive for simulations of this kind. As a result, vast majority of CFD simulations employ RANS equations in conjunction with a turbulence model. In order to assess the modeling requirements (mesh, numerical algorithm, turbulence model etc.) for accurate simulations, it is critical to validate the calculations against the experimental data. For this purpose, we use three well known benchmark validation cases, one for natural convection in 2D closed vertical cavity, second for forced convection in a 2D rectangular cavity and the third for mixed convection in a 2D square cavity. The simulations are performed on a number of meshes of different density using a number of turbulence models. It is found that k-epsilon two-equation turbulence model with a second-order algorithm on a reasonable mesh gives the best results. This information is then used to determine the modeling requirements (mesh, numerical algorithm, turbulence model etc.) for flows in 3D enclosures with different ventilation systems. In particular two cases are considered for which the experimental data is available. These cases are (1) air flow and heat transfer in a naturally ventilated room and (2) airflow and temperature distribution in an atrium. Good agreement with the experimental data and computations of other investigators is obtained.
Dynamic Modeling of a Solar Reactor for Zinc Oxide Thermal Dissociation and Experimental Validation Using IR Thermography
Authors: Villasmil W. , Meier A. , Steinfeld A.
Published: December 2013

A dynamic numerical model of a solar cavity-type reactor for the thermal dissociation of ZnO is formulated based on a detailed radiative heat transfer analysis combining the Monte Carlo ray-tracing technique and the radiosity enclosure theory. The quartz window is treated as a semi-transparent spectrally-selective glass layer with directionally dependent optical properties. Model validation is accomplished by comparison with experimental results obtained with a 10-kW solar reactor prototype in terms of cavity temperatures, reaction extents, and quartz window temperature distribution measured by IR thermography. The solar-to-fuel energy conversion efficiencies obtained experimentally are reported and the various energy flows are quantified.